Saturday, July 26, 2008
Pure eccentric exercise does not activate blood coagulation
Abstract Eccentric exercise can cause skeletal muscle damage with ultrastructural disruption, inflammation and increased proteolytic enzyme activity. It may be possible that these changes are able to trigger blood coagulation in vivo. The aim of the study was to investigate changes in blood coagulation via the measurement of aPTT, the thrombin potential (total [TTP] and endogenous [ETP], both intrinsic [in] and extrinsic [ex]) and the thrombin generation (prothrombinfragment 1+2 [F1+2] and thrombin-antithrombin complex [TAT]) after pure eccentric exercise. Seventeen healthy non-smokers (28±6 years, VO2-peak 59±7 ml/min/kg) underwent pure eccentric down jumps (9×28 isolated down jumps in 90 min, drop from a height of 55 cm), a cycle exercise (90% of the individual anaerobic threshold for 60–90 min) and a control experiment on different days. Blood samples were drawn after a 30-min rest, immediately, and 2 h after exercise. After the cycle exercise, a clear shortening by 12% (PPP<0.05) in comparison to the control experiment were seen, while after eccentric exercise only minimal changes in aPTT and thrombin potential (TTPin, ETPin) and no thrombin generation (F1+2 and TAT) were found. In contrast to concentric dynamic exercise, e.g. cycle ergometry, only insignificant changes in thrombin potential and no thrombin generation could be observed after skeletal muscle damage induced by pure eccentric exercise. It can be concluded that the mechanical impact associated with eccentric exercise does not activate blood coagulation.
Wednesday, July 23, 2008
Hypertension and dementia: Does blood pressure control favorably affect cognition?
Abstract Dementia and aging are not synonymous. Dementia is a progressive deterioration in cognitive and social and/or occupational functions that can eventually impair a patient’s ability to live independently. Alzheimer’s disease is the most common form of dementia. It accounts for 50% to 70% of all patients with dementia. Vascular dementia, responsible for up to 15% of all diagnosed cases, is the second most common form of dementia. Hypertension remains a significant risk factor for vascular dementia. The optimal level of blood pressure control for the prevention of dementia and whether one particular class of antihypertensive drug is more beneficial than another remains uncertain.
Nanomechanical characterization of red blood cells using optical tweezers
Abstract Deformation behaviours of red blood cells (RBCs) have been studied by applying stretching forces via optical tweezers. Combined with finite-element analyses (FEA), the RBCs’ mechanical properties are determined quantitatively based on a best fitting between the experimental deformed geometries and the simulated counterparts. Experimentally, a silica beads attached erythrocyte is optical-mechanically stretched to different lengths. On the theoretical front, a large deformation model with Mooney-Rivlin constitutive equations has been simulated by using FEA to predict the cell deformation geometries. The numerically simulated transverse and longitudinal strains which are in a good agreement with the experimental measurements facilitate the determination of elastic constants of the cells.
Non-gated fetal MRI of umbilical blood flow in an acardiac twin
Abstract Currently, the standard method of diagnosis of twin reversed arterial perfusion (TRAP) sequence is ultrasound imaging. The use of MRI for flow visualization may be a useful adjunct to US imaging for assessing the presence of retrograde blood flow in the acardiac fetus and/or umbilical artery. The technical challenge in fetal MRI flow imaging, however, is that fetal electrocardiogram (ECG) monitoring required for flow imaging is currently unavailable in the MRI scanner. A non-gated MRI flow imaging technique that requires no ECG monitoring was developed using the t-test to detect blood flow in 20 slices of phase-contrast MRI images randomly scanned at the same location over multiple cardiac cycles. A feasibility study was performed in a 24-week acardiac twin that showed no umbilical flow sonographically. Non-gated MRI flow images clearly indicated the presence of blood flow in the umbilical artery to the acardiac twin; however, there was no blood flow beyond the abdomen. This study leads us to conjecture that non-gated MRI flow imaging is sensitive in detecting low-range blood flow velocity and can be an adjunct to Doppler US imaging.
Blood pressure nomograms for school children in Iran
Abstract Currently there are no blood pressure (BP) nomograms based on local data available in Iran. In order to obtain data on BP distribution in Iranian school children, 8,848 children aged 7–12 years were studied in Tehran. BP was found to increase with age. Both systolic and diastolic BP showed a positive correlation with height and weight in both sexes. The systolic and diastolic BP in boys and girls were not significantly different. As the sample was representative of Iranian school children, reference standard curves were constructed by modeling data using fractional polynomial. The 50th and 95th percentiles of systolic and diastolic BP of Iranian children were compared for each age with the results reported in the study of the Second Task Force. These percentiles were different from the Second Task Force study. Environmental and genetic determinants are likely to be responsible for the differences. The differences show that the use of local BP nomograms is necessary for assessing the BP levels in Iranian children.
Preparation and blood coagulation evaluation of chitosan microspheres
Abstract Cross-linked chitosan microspheres (40–100 μm) with smooth surface were prepared by the methods of emulsification and ethanol coagulant. FTIR results showed that the cross-linking reaction occurred on the amino groups of chitosan molecules. The swelling characteristic of chitosan microspheres was influenced by the environment pH, being generally greater at low rather than higher pH values. The coagulation properties of chitosan microspheres were evaluated by dynamic blood clotting, platelet adhesion and activation, erythrocyte adhesion, hemolysis, and protein absorption assays. Chitosan microspheres can shorten the clotting time and induce the adhesion and activation of platelets. But the shortening of clotting time by chitosan microspheres may be related to not only platelet aggregation, but also erythrocyte aggregation. Take together, chitosan microspheres may be potential use as thrombospheres.
Cord-blood mesenchymal stem cells and tissue engineering
Abstract Cord-blood-derived stem cells have proven clinically useful for numerous disease states, as have mesenchymal stem cells (MCSs) derived from bone marrow and adipose tissue. The recent identification of MSCs in cord-blood heralds cord-blood as an untapped resource for nonhematopoietic stem cell-based therapeutic strategies for the replacement of injured or disease connective tissue. This review discusses the potential for tissue engineering applications of MSCs, highlighting the development of vascularized tissue engineering constructs using microvascular free flaps as a novel tissue engineering strategy.
Prostaglandin E 1 reduces blood loss during and after resection of lumbar herniated disc
Abstract Controlled hypotension was employed during resection of lumbar herniated disc on 10 patients. Prostaglandin E1 (PG) was used as a hypotensive agent. The systolic blood pressure was lowered less than 100mmHg in the hypotensive group. The average blood loss during surgery was 95 ± 41ml for the hypotensive group compared with 154 ± 81ml for the normotensive group (P 0.05). The blood loss after surgery was also significantly less in the hypotensive group than in the normotensive group (P 0.05). We conclude that PG is an effective hypotensive agent on blood loss during and after surgery.(Kashimoto S, Nakamura T, Yamaguchi T: Prostaglandin E1 reduces blood loss during and after resection of lumbar herniated disc. J Anesth 6: 294–296, 1992)
MR angiography with blood pool contrast agents
Abstract Contrast-enhanced magnetic resonance angiography (CE-MRA) with standard extracellular contrast material is well established for vascular imaging. Recently, the first blood pool contrast agent (BPA) has become clinically available. This paper reviews characteristics and classification of BPA as well as first clinical experience in various vascular territories. BPAs comprise gadolinium-based compounds, synthetic compounds, and ultrasmall superparamagnetic iron-oxide (USPIO) particles. Such BPAs are retained in blood with a prolonged time-window of enhancement as compared to extracellular gadolinium chelates. Promising results from USPIO at first-pass and steady-state angiography have been published, but no USPIO is approved yet. Gadofosveset is the first clinically approved BPA. After bolus injection, gadofosveset binds noncovalently to serum-albumine, thus enhancing relaxivity. First published results from carotid, coronary, renal, and peripheral angiography are encouraging; particularly helpful is prolonged enhancement during steady state. More BPAs have been clinically evaluated, but no approval has been granted. Bolus-injectable BPAs allow for first-pass CE-MRA similar to standard extracellular contrast media, but with higher relaxivity, allowing lower doses and reduced injection rates. An additional feature of BPA is the steady-state phase with a broad time window enabling high-resolution angiography or double-gated angiography of coronary arteries to compensate for the complex motion pattern.
Conditions that influence bacterial luminescence in the presence of blood serum
Abstract Conditions that influence the luminescence of natural and recombinant luminescent bacteria in the presence of blood serum were studied. In general, blood serum quenched the luminescence of the marine Photobacterium phosphoreum and the recombinant Escherichia coli strains harboring the luminescent system genes of Photobacterium leiognathi, but enhanced the luminescence of the soil bacterium Photorhabdus luminescens Zm1 and the recombinant E. coli strain harboring the lux operon of P. luminescens Zm1. The quenching effect of blood serum increased with its concentration and the time and temperature of incubation. The components of blood serum that determine the degree and specificity of its action on bacterial luminescence were identified.
CT perfusion cerebral blood flow imaging in neurological critical care
Abstract Computed tomography (CT) perfusion imaging is a technique for the measurement of cerebral blood flow, cerebral blood volume, and time-to-peak or mean transit time. The technique involves the administration of a single-bolus dose of iodinated contrast material, followed by spiral CT imaging during the passage of the contrast bolus through the cerebral vasculature. CT perfusion is a fast and inexpensive brain imaging modality for use in the management of patients with various neurological disorders, ranging from acute stroke to subarachnoid hemorrhage. This article reviews the technique of CT perfusion and presents several illustrative cases in which this imaging modality was used effectively in the critical care of patients with neurological disorders.
Comparison of bicarbonate and base excess values analyzed by four different blood gas analyzers
Abstract Comparison of the calculation formula, reproducibility, correlation and variation of bicarbonate ion concentration (HCO3 −), and base excess value (BE) among four blood-gas analyzers was performed. No HCO3 − and BE values calculated from the formulas showed any clinically significant difference, and all analyzers showed good correlation on their measurements. On the actual measurement of a specific sample, however, BE values from the same sample ranged between −6.3 and −15.7, which might affect therapeutic strategy. Caution should be taken for the assessment of data if different types of blood-gas analysis devices are used in the same facility.
Guiding antihypertensive treatment decisions using ambulatory blood pressure monitoring
Abstract Compared with isolated clinic measurements, ambulatory blood pressure monitoring (ABPM) provides an insight into blood pressure (BP) changes in everyday life and an estimate of the overall BP load exerted on the cardiovascular system over 24 hours. Cross-sectional evidence suggests a direct and significant relationship between ambulatory BP and organ damage. There is also longitudinal evidence for a superior predictive value of 24-hour BP in relation to the risk for cardiovascular morbidity and mortality as opposed to clinic BP. The usefulness of ABPM in pharmacologic studies aimed at evaluating the 24-hour antihypertensive efficacy of different drugs and drug combinations is now acknowledged. Among the mathematical indices available to explore 24-hour BP coverage by treatment, the ABPM-derived smoothness index provides a superior measure of the homogeneity of BP control compared with trough:peak ratios. The main applications of clinical practice should be in identifying patients with isolated office hypertension and those who are nonresponders to treatment, in assessing coverage of the 24-hour BP profile in high-risk patients and in diagnosing suspected treatment-related hypotension.
The world health organization—International society of hypertension blood pressure lowering treatment trialists’ collaboration: Prospective collaborative overviews of major randomized trials of blood pressure-lowering treatments
Abstract Clear evidence shows that decreasing blood pressure reduces risks for major cardiovascular events in patients with hypertension. However, there is considerable uncertainty about the separate effects of the various classes of blood pressure-lowering agents and the effects of blood pressure lowering in patients at high risk, particularly in the absence of hypertension. Several new randomized controlled trials have been started in the past few years in an effort to address these questions. However, individually, these studies are unlikely to resolve all current uncertainties. For this reason, systematic overviews and meta-analyses of the major ongoing trials are planned. The overviews will be conducted as a collaboration among the principal investigators of the participating trials and will involve about 270,000 patients and 1.1 million patientyears of follow-up. The combined trial results should provide good statistical power to detect even modest differences in the effects of various treatments on major cardiovascular outcomes.
Circulating DNA in the blood and its application in medical diagnosis
Abstract Circulating nucleic acids were discovered more than 30 years ago, but did not attract much attention until the past decade. This review summarizes the data on the sources of extracellular DNA circulating in the blood, features of its circulation, and pathways of its removal. The possibility of using circulating DNA in medical diagnosis is discussed.
Acute Effect of Cigarette Smoke and Nicotine on Airway Blood Flow and Airflow in Healthy Smokers
Abstract Cigarette smoke contains irritants and vasoactive substances. We wanted to determine the effect of smoking a cigarette and of nasally or orally inhaled nicotine on airway blood flow (Qaw) and airflow in smokers. In ten healthy current smokers, Qaw, FEV1, and FEF25–75 were measured before and at 5, 30, and 180 min after smoking a cigarette. The effects of systemic nicotine using a nicotine nasal spray and local nicotine using a nicotine inhaler were also studied. Mean (± SE) Qaw increased by 81% ± 16% (p = 0.03) 5 min after smoking a cigarette and was no longer different from baseline at 30 and 180 min. Nicotine nasal spray and nicotine oral inhaler had no effect on Qaw. FEV1 and FEF25-75 remained unchanged after smoking a cigarette and after local or systemic nicotine administration. Smoking a cigarette is followed by a transient increase in airway blood flow but no changes in airflow. Nicotine, at the rate and dose provided by the nasal spray (systemic action) and oral inhaler (local and systemic action), does not appear to be involved in the Qaw change, suggesting a pharmacologic or nonspecific irritant effect of other cigarette smoke constituents.
Molecular Mechanisms of Changes in TNF-α Production by Blood Mononuclears in Chronic Viral Hepatitis C
Abstract Chronic viral hepatitis C is associated with decreased production of TNF- by the peripheral blood mononuclear leukocytes irrespective of virus genotype and degree of the morphological activity of the process in the liver. This process positively correlates with the increase in the content of TNF- soluble receptor (molecular weight 55 kDa), which can play a role in the mechanisms of immunopathogenesis of long persistence of hepatitis C virus in the body.
Mycoplasma blood infection in chronic fatigue and fibromyalgia syndromes
Abstract Chronic fatigue syndrome (CFS) and fibromyalgia syndrome (FMS) are characterised by a lack of consistent laboratory and clinical abnormalities. Although they are distinguishable as separate syndromes based on established criteria, a great number of patients are diagnosed with both. In studies using polymerase chain reaction methods, mycoplasma blood infection has been detected in about 50% of patients with CFS and/or FMS, including patients with Gulf War illnesses and symptoms that overlap with one or both syndromes. Such infection is detected in only about 10% of healthy individuals, significantly less than in patients. Most patients with CFS/FMS who have mycoplasma infection appear to recover and reach their pre-illness state after long-term antibiotic therapy with doxycycline, and the infection can not be detected after recovery. By means of causation and therapy, mycoplasma blood infection may permit a further subclassification of CFS and FMS. It is not clear whether mycoplasmas are associated with CFS/FMS as causal agents, cofactors, or opportunistic infections in patients with immune disturbances. Whether mycoplasma infection can be detected in about 50% of all patient populations with CFS and/or FMS is yet to be determined.
Effects of cholecystokinin on gastric injury and gastric mucosal blood flow
Abstract Cholecystokinin (CCK). IS a vasodilator and prevents gastric injury from ethanol. Its effects against other irritants are unknown. This study was conducted to (1) assess whether CCK or oleate, a CCK secretagogue, could prevent gastric injury from other damaging agents and (2) examine the role of blood flow in CCK-induced gastroprotection. Conscious rats were pretreated for 10 minutes with intravenous saline solution or CCK (5 nrnol/kg) or were given 1 ml of orogastric water or oleate (100 mmol/L) 3 0 minutes before a 1 n-d orogastric bolus of acidified ethanol (150 mmol/L hydrochloric acid/50% ethanol), 0.75N hydrochloric acid, or 0.2N sodium hydroxide. Rats were killed 5 minutes after receiving an irritant and the total area (mm2) of macroscopic injury was quantified. The duration of CCK-induced gastroprotection against acidified ethanol was examined at 5,10,30, and 60 minutes after its administration. Other rats had gastric mucosal blood flow determined (fluorescent microspheres) at identical time points. CCK and oleate decreased gastric injury from all three luminal irritants. CCK-induced gastroprotection was present for 30 minutes but only enhanced gastric mucosal blood flow at 5 and 10 minutes. These data suggest that endogenous CCK may play a role in gastric mucosal defense and that blood flow alone does not fully explain CCK gastroprotection.
Fish blood as a chemical signal for Antarctic marine invertebrates
Abstract Chemical cues released from dead or injured organisms constitute important signals informing nearby animals about a feeding possibility. The ability to detect the signal, evaluate its meaning and locate its source can help organisms to exploit food resources efficiently, which is especially important to animals living in environments with limited food supply. Experiments were carried out to study the behavioral responses of several Antarctic benthic invertebrates to fish (Notothenia corriceps) blood. Necrophagous species such as sea stars Odontaster validus and Lysasterias sp., amphipod Waldeckia obesa and nemertean Parborlasia corrugatus responded to fish blood with changes in their behavior. The behavior common to all these species was locomotion directed towards the stimulus source. Behavioral components consistent with food consumption were observed in O. validus and P. corrugatus. The reaction of herbivorous limpets Nacella concinna to fish blood depended on the animal size. Large (>10 mm) limpets showed no behavioral response, whereas small ones (<10 mm) reacted to the stimulus by moving a short distance away. These results indicate that blood released from the tissues of injured or dead animals may be an important chemical signal for organisms belonging to different taxa.
Effect of Hypoxia on Physiological-Biochemical Blood Parameters in Some Marine Fish
Abstract Changes of hematocrit, hemoglobin, and blood plasma glucose and Na+ and K+ content in response to hypoxia were studied in three Black Sea fish species. It was shown that in response to hypoxia in low-mobile rock perch Scorpaena porcus L., hematocrit and the blood plasma glucose level increased, while the content of K+ in erythrocytes decreased and the content of Na+ increased. In moderately mobile sea carp Diplodus annularis L. autogenic hypoxia caused a rise of hematocrit and blood plasma glucose. In actively swimming jack mackerel Trachurus mediterraneus ponticus Aleev, only considerable increase of Na+ content was revealed in hypoxia. The obtained results indicate that fish with different mobility under hypoxic conditions use different adaptation mechanisms. The value and direction of changes of the chosen parameters can be used to determine resistance of fish to oxygen deficit.
Changes in circulating blood volume following isoflurane or sevoflurane anesthesia
Abstract Changes of circulating blood volume (CB volume) measured by the dual indicator dilution method were observed in 33 chronically instrumented mongrel dogs following either alpha-chloralose-urethane (C group), additive isoflurane (I group) or sevoflurane anesthesia (S group). These anesthetic groups were each divided into two subgroups with regard to respiratory care, namely Cp, Ip and Sp for those with intermittent positive pressure ventilation (six animals per subgroups), and Cs, Is and Ss for those with spontaneous breathing (five animals per subgroups).The CB volume under positive pressure ventilation remained unchanged in the Ip and Sp groups at both 0.5 and 1.0 MAC, and in the Cp group. The CB volume remained essentially unchanged in the Cs and Is groups at both 0.5 or 1.0 MAC, but the plasma volume tended to increase slightly in the Is group at 1.0 MAC.
Effects of various hyperbaric gas mixtures on hormonal parameters of healthy human blood and saliva
Abstract Changes in some hormonal parameters of healthy subjects were studied during experimental 3- to 18-day dives in hyperoxic (oxygen-nitrogen-helium) and argon-containing (normoxic and hyperoxic) gas mixtures. The blood levels of growth hormone, corticotropin, thyrotropin (TSH), thyroid hormones, total cortisol, insulin, and C-peptide, as well as the total salivary free cortisol, were measured during and after hyperbaric exposure. In most cases, the changes in these parameters did not exceed normal clinical and individual ranges. A statistically significant increase in the total cortisol and blood TSH were detected during the exposure to hypoxic oxygen-nitrogen and oxygen-nitrogen-argon mixtures. The time course of salivary free cortisol indicated the most stressful periods of the experimental exposures.
Red blood cell rheology in sepsis
Abstract Changes in red blood cell (RBC) function can contribute to alterations in microcirculatory blood flow and cellular dysoxia in sepsis. Decreases in RBC and neutrophil deformability impair the passage of these cells through the microcirculation. While the role of leukocytes has been the focus of many studies in sepsis, the role of erythrocyte rheological alterations in this syndrome has only recently been investigated. RBC rheology can be influenced by many factors, including alterations in intracellular calcium and adenosine triphosphate (ATP) concentrations, the effects of nitric oxide, a decrease in some RBC membrane components such as sialic acid, and an increase in others such as 2,3 diphosphoglycerate. Other factors include interactions with white blood cells and their products (reactive oxygen species), or the effects of temperature variations. Understanding the mechanisms of altered RBC rheology in sepsis, and the effects on blood flow and oxygen transport, may lead to improved patient management and reductions in morbidity and mortality.
Effects of various hyperbaric gas mixtures on metabolic parameters of human blood
Abstract Changes in metabolic parameters of healthy subjects were studied during experimental 4-to 21-day courses of simulated diving in hyperbaric normoxic (oxygen-helium), hyperoxic (oxygen-nitrogen-helium), and argon-containing gas mixtures with different oxygen contents. The blood concentrations of primary substrates and activity of enzymes were measured spectrophotometrically. In most cases, the clinical and biochemical parameters of the blood remained within normal clinical ranges and exhibited significant individual variations. Long-term simulated deep dives (>200 m) resulted in changes in lipid metabolism expressed as an increase in the plasma concentrations of triglycerides, low-density lipoproteins, and polyunsaturated fatty acids. No significant changes were found during experimental 70-m dives performed according to recompression treatment table with the use of a hyperoxic helium-containing gas mixture. In contrast, long-term exposure to a normoxic argon-containing mixture at a pressure of 5 msw caused a significant increase in the blood contents of triglycerides, total cholesterol, and glucose, as well as a smaller increase in the activities of several tissue enzymes. At the same pressure, hypoxic oxygen-nitrogen-argon and oxygen-nitrogen mixtures did not affect the majority of clinical and biochemical parameters examined. However, in some subjects, they increased the atherogenicity index, concentrations of triglycerides, and activities of lactate dehydrogenase and alkaline phosphatase. The absence of any pathological changes in clinical and biochemical parameters of the blood indicates that both gas mixtures are safe and can be used in barochambers. Episodic changes in lipid metabolism and enzyme activities observed in healthy subjects exposed to helium-and argon-containing gas mixtures can be interpreted as a reversible hepatic dysfunction due to the high pressure. The extent of the changes in the parameters of lipid metabolism in the blood is determined by the magnitude of the overpressure and the duration of the exposure.
Reduced cerebral blood flow and N-acetyl aspartate in a murine model of cerebral malaria
Abstract Cerebral malaria is an important cause of morbidity and mortality in many parts of the world. It has been suggested that cerebral malaria is associated with reduced perfusion due to the blockage of blood vessels by parasitized erythrocytes; although, no quantitative validation of this has been done. We infected C57BL/6 mice with the ANKA strain of Plasmodium berghei and on day 6 of infection we investigated alterations in brain function using arterial spin labeling MRI and proton MRS. MR images did not demonstrate signs of damage. However, there was a significant reduction in cerebral blood flow (PPr=0.87) suggesting a relationship between impaired oxygen delivery and neuronal dysfunction. Pathological examination revealed accumulations of damaged axons providing a correlate for the decreased NAA/Cr ratio in infected mice. This murine model will permit non-invasive studies of neurologic function during malarial infection.
Nonlinear Assessment of Cerebral Autoregulation from Spontaneous Blood Pressure and Cerebral Blood Flow Fluctuations
Abstract Cerebral autoregulation (CA) is an most important mechanism responsible for the relatively constant blood flow supply to brain when cerebral perfusion pressure varies. Its assessment in nonacute cases has been relied on the quantification of the relationship between noninvasive beat-to-beat blood pressure (BP) and blood flow velocity (BFV). To overcome the nonstationary nature of physiological signals such as BP and BFV, a computational method called multimodal pressure-flow (MMPF) analysis was recently developed to study the nonlinear BP–BFV relationship during the Valsalva maneuver (VM). The present study aimed to determine (i) whether this method can estimate autoregulation from spontaneous BP and BFV fluctuations during baseline rest conditions; (ii) whether there is any difference between the MMPF measures of autoregulation based on intra-arterial BP (ABP) and based on cerebral perfusion pressure (CPP); and (iii) whether the MMPF method provides reproducible and reliable measure for noninvasive assessment of autoregulation. To achieve these aims, we analyzed data from existing databases including: (i) ABP and BFV of 12 healthy control, 10 hypertensive, and 10 stroke subjects during baseline resting conditions and during the Valsalva maneuver, and (ii) ABP, CPP, and BFV of 30 patients with traumatic brain injury (TBI) who were being paralyzed, sedated, and ventilated. We showed that autoregulation in healthy control subjects can be characterized by specific phase shifts between BP and BFV oscillations during the Valsalva maneuver, and the BP–BFV phase shifts were reduced in hypertensive and stroke subjects (P < 0.01), indicating impaired autoregulation. Similar results were found during baseline condition from spontaneous BP and BFV oscillations. The BP–BFV phase shifts obtained during baseline and during VM were highly correlated (R > 0.8, P < 0.0001), showing no statistical difference (paired-t test P > 0.47). In TBI patients there were strong correlations between phases of ABP and CPP oscillations (R = 0.99, P < 0.0001) and, thus, between ABP–BFV and CPP–BFV phase shifts (P < 0.0001, R = 0.76). By repeating the MMPF 4 times on data of TBI subjects, each time on a selected cycle of spontaneous BP and BFV oscillations, we showed that MMPF had better reproducibility than traditional autoregulation index. These results indicate that the MMPF method, based on instantaneous phase relationships between cerebral blood flow velocity and peripheral blood pressure, has better performance than the traditional standard method, and can reliably assess cerebral autoregulation dynamics from ambulatory blood pressure and cerebral blood flow during supine rest conditions.
Phagocytic Function of Human Blood Polymorphonuclear Leukocytes in the Presence of Carrageenan, a Potential Vaginal Microbicide
Abstract Carrageenan is currently undergoing clinical trials as the active constituent of a vaginal gel product for use as a female-controlled option to prevent the transmission of HIV during sexual intercourse. Here we show that in the presence of 0.5 mg/ml of carrageenan, human blood polymorphonuclear leukocytes (PMN) do not ingest this material, as evidenced by a lack of progressive vacuolization, but can ingest microorganisms present in the medium, excluding adjacent carrageenan. Moreover, PMN move at normal speeds, respond chemotactically, and reduce netroblue tetrazolium (NBT) to formazan on stimulation. Hence, in the presence of carrageenan the phagocytic response appears to remain intact.
Changes of blood pressure and left ventricular mass in pediatric renal transplantation
Abstract Cardiovascular events are among the most frequent causes for long-term morbidity and mortality in children after renal transplantation. The aim of this study was to analyze the effects of post-transplant changes in arterial hypertension, as assessed by 24-h ambulatory blood pressure measurement (ABPM), on myocardial architecture, as assessed by echocardiography. In a retrospective chart review analysis, 39 children were identified in whom 24-h ABPM and echocardiography had been assessed within a 3-month interval after a mean of 4 years post transplantation; 20 repeated pairs of measurements after a mean of 2 years of follow-up were available to analyze the longitudinal effects of post-transplant changes of blood pressure control on left ventricular mass index (LVMI). Arterial hypertension (59%) and left ventricular hypertrophy (50%) were highly prevalent in children after renal transplantation. Renal allograft function and number of antihypertensive medications, but not ABPM variables, were correlated with LVMI at the initial observation. However, at repeat assessment, a significant correlation between ABPM and LVMI was found. In the longitudinal assessment, left ventricular remodeling was dependent on change of dosage of cyclosporine and interval changes of blood pressure levels. Hence, control of blood pressure correlates with changes of LVMI in children with renal allografts. These results clearly underline the importance of blood pressure control for the maintenance of the myocardial architecture.
Right atrial blood cyst with total occlusion of the right coronary artery
Abstract Cardiac blood cysts are rarely seen in adult patients and in the right atrium. The origin of cardiac blood cysts is not understood, and several hypotheses have been proposed. We present a rare case of right atrial blood cyst with total occlusion of the right coronary artery (RCA). Inflammatory processes may have played an important role in the development of the cyst, because infiltration of inflammatory cells was observed in the cystic wall. Additionally, total obstruction of the proximal RCA indicated that ischemia and/or infarction in the right atrium might be related to formation of the cyst.
Involvement of calcitonin gene-related peptide in migraine: regional cerebral blood flow and blood flow velocity in migraine patients
Abstract Calcitonin gene-related peptide (CGRP)-containing nerves are closely associated with cranial blood vessels. CGRP is the most potent vasodilator known in isolated cerebral blood vessels. CGRP can induce migraine attacks, and two selective CGRP receptor antagonists are effective in the treatment of migraine attacks. It is therefore important to investigate its mechanism of action in patients with migraine. We here investigate the effects of intravenous human alpha-CGRP (hαCGRP) on intracranial hemodynamics. In a double-blind, cross-over study, the effect of intravenous infusion of hαCGRP (2 μg/min) or placebo for 20 min was studied in 12 patients with migraine without aura outside attacks. Xenon-133 inhalation SPECT-determined regional cerebral blood flow (rCBF) and transcranial Doppler (TCD)-determined blood velocity (V mean) in the middle cerebral artery (MCA), as well as the heart rate and blood pressure, were the outcome parameters. No change of rCBF was observed at the end of infusion [1.2% ± 1.7 with hαCGRP, vs. −1.6% ± 3.1 with placebo (mean ± SD)] (P = 0.43). V mean in MCA decreased to 13.5% ± 3.6 with hαCGRP versus 0.6% ± 1.8 with placebo (P < 0.005). Since rCBF was unchanged, this indicates a dilation of the MCA. hαCGRP induced a decrease in MAP (12%) (P < 0.005) and an increase in heart rate (58%) (P < 0.0001). CGRP dilates cerebral arteries, but the effect is so small that it is unlikely to be the only mechanism of CGRP-induced migraine.
Cadmium, Lead, and Selenium in Cord Blood and Thyroid Hormone Status of Newborns
Abstract Cadmium (Cd), lead (Pb), and selenium (Se) concentrations in cord whole blood, sampled from 24 women at the time of delivery in a hospital in Tokyo in 2005, were determined by inductively coupled plasma mass spectrometry with a reaction cell. Signal enhancement caused by nonspectroscopic interference for Se was evident and the standard addition technique was essential for correcting the interference. Median concentration in cord bloods was 0.20 ng/g, 6.7 ng/g (0.67 μg/dL), and 191 ng/g for Cd, Pb and Se, respectively. Lead concentration was lower, whereas Se concentration was higher, than those reported in other countries. The trace element concentration was related to the levels of thyroid stimulating hormone (TSH) and free thyroxin (fT4) in the neonatal blood sampled at 4–6 days postpartum. A significantly negative correlation was observed between Cd concentrations in cord blood and TSH concentration in neonatal blood. The result indicated the possible effect of in utero Cd exposure on thyroid hormone status of newborns and that Cd exposure level should be assessed as a covariate in the survey on the relationship between in utero chemicals (e.g., PCBs) exposure and thyroid hormone status.
Production of the blood pressure lowing peptides from brown alga ( Undaria pinnatifida )
Abstract Brown alga (Undaria pinnatifida) was treated with alginate lyase and hydrolyzed using 17 kinds of proteases and the inhibitory activity of the hydrolysates for the angiotensin-I-converting enzyme (ACE) was measured. Four hydrolysates with potent ACE-inhibitory activity were administered singly and orally to spontaneously hypertensive rats (SHRs). The systolic blood pressure of SHRs decreases significantly after single oral administration of the brown alga hydrolysates by protease S ‘Amano’ (from Bacillus stearothermophilus) at the concentration of 10 (mg protein) (kg body weight)−1. In the 17 weeks of feeding experiment, 7-week-old SHRs were fed standard diet supplemented with the brown alga hydrolysates for 10 weeks. In SHRs fed 1.0 and 0.1% brown alga hydrolysates, elevating of systolic bloodpressure was significantly suppressed for 7 weeks. To elucidate the active components, the brown alga hydrolysates were fractionated by 1-butanol extraction and HPLC on a reverse-phase column. Seven kinds of ACE-inhibitory peptides were isolated and identified by amino acid composition analysis, sequence analysis, and LC-MS with the results Val-Tyr, Ile-Tyr, Ala-Trp, Phe-Tyr, Val-Trp, Ile-Trp, and Leu-Trp. Each peptide was determined to have an antihypertensive effect after a single oral administration in SHRs. The brown alga hydrolysates were also confirmed to decrease the blood pressure in humans.
Effects of medications on cerebral blood flow in late-life depression
Abstract Both normal aging and late-life depression (LLD) are associated with reductions in regional cerebral blood flow (rCBF). The impact of medication treatment in baseline rCBF abnormalities in LLD is being investigated via functional imaging research. Some of this work can be informed by pharmacologic challenge studies, which exploit the role of serotonin in regulating rCBF. Preliminary evidence suggests that there may be both state- and trait-level disturbances in rCBF in LLD, and that a common pathway towards clinical response to somatic antidepressant treatments involves reduction in rCBF in critical prefrontal cortical brain regions. Studies of the effects of medications on rCBF in LLD have implications for understanding the neurobiology of treatment resistance in the elderly as well as the mechanisms of action of antidepressant treatments.
Viable CD34+/CD133+ blood progenitor cell dose as a predictor of haematopoietic engraftment in multiple myeloma patients undergoing autologous peripheral blood stem cell transplantation
Abstract Both CD34 (cluster of differentiation 34) and the more recently described CD133 are markers of primitive stem cells with haematopoietic repopulating ability. Most transplanting centres use a minimum number of CD34+ cells as the requirement for a transplant and consider this a predictor of haematopoietic engraftment. However, transplanted CD34+ cell dose does not always give a close correlation with time to engraftment nor explain delayed engraftment in some patients. We have retrospectively evaluated the potential of measuring viable CD133+ cell numbers in the autograft as an alternative predictor of haematological engraftment after autologous stem-cell transplantation in a cohort of patients with multiple myeloma (MM). We found an average 32% loss of viability of CD34+ cells in the post-thaw sample compared with the fresh sample. Of the original estimated CD34+ cell numbers transplanted per kg, 43% of the thawed samples were double positive for CD34+/CD133+. In this patient group, the CD34+/CD133+ subset gave the closest statistical correlation with time to neutrophil engraftment (p < 0.05), particularly for patients given above median (1.8 × 106/kg) dose of the double-positive cells. The CD34+/CD133+ population was the only parameter to give a significant correlation with white cell engraftment in this patient cohort (p < 0.05). There was no significant correlation between CD34+, viable CD34+ or viable CD34+/CD133+ cells/kilogram with platelet engraftment. Determination of viable CD34+/CD133+ progenitor cell dose in the autograft may be a useful tool to predict neutrophil recovery after autologous transplantation than conventional assessment of CD34+ numbers. These results warrant further investigation of the role of CD133 in haematopoietic engraftment.
Are clinical endpoint benefits of angiotensin converting enzyme inhibitors independent of their blood pressure effects?
Abstract Both basic and experimental data indicate that the reninangiotensin system through angiotensin II mediates its classic hemodynamic role, but also has a significant deleterious role in a number of cardiac, vascular, and renal disorders. Indeed, evidence indicates that angiotensin II negatively impacts endothelial function, cardiac remodeling, vessel wall hypertrophy, atherosclerosis, and progressive renal disease. Newer data point to a significant role for angiotensin II in inflammation and in inducing plasminogen activator inhibitor. This widespread negative effect can be countered by newer antihypertensive drugs, angiotensin converting enzyme inhibitors, and angiotensin receptor blockers. Both small and large clinical trials suggest a large benefit of such drugs on not only organ-specific endpoints such as renal disease or proteinuria, but on global cardiovascular events. It does appear that when blood pressure is significantly elevated, lowering blood pressure does indeed provide protection for larger endpoints such as stroke. However, at lower blood pressure levels, a hemodynamically independent effect is likely to be contributing to the positive effects. We should embrace these effects and champion them for our patients.
Necrophysiological determination of blood pressure in fishes
Abstract Bony fishes have an elastic chamber between the heart and aorta, the bulbus arteriosus, which has unique mechanical properties. On inflation, the isolated bulbus is initially very stiff but soon becomes extremely compliant yielding a steady (plateau) pressure upon further inflation, which appears to be similar in any given species. Here we show that the plateau pressure correlates with mean blood pressure determined in vivo. Consequently, inflation of the bulbus can be used to determine blood pressure in the living animal from recordings made after it is dead.
Characterization of osteoclasts derived from CD14+ monocytes isolated from peripheral blood
Abstract Bone resorption is solely mediated by osteoclasts. Therefore, a pure osteoclast population is of high interest for the investigation of biological aspects of the osteoclasts, such as the direct effect of growth factors and hormones, as well as for testing and characterizing inhibitors of bone resorption. We have established a pure, stable, and reproducible system for purification of human osteoclasts from peripheral blood. We isolated CD14-positive (CD14+) monocytes using anti-CD14-coated beads. After isolation, the monocytes are differentiated into mature osteoclasts by stimulation with macrophage colony-stimulating factor (M-CSF) and receptor activator of nuclear factor κB ligand (RANKL). Osteoclast formation was only observed in the CD14+ population, not in the CD14− population, and only in the presence of both M-CSF and RANKL, confirming that the CD14+ system is a pure population of osteoclast precursors. No expression of osteoclast markers was observed in the absence of RANKL, whereas RANKL dose-dependently induced the expression of cathepsin K, tartrate-resistant acid phosphatase (TRACP), and matrix metallo proteinase (MMP)-9. Furthermore, morphological characterization of the cells demonstrated that actin rings were only formed in the presence of RANKL. Moreover, the osteoclasts were capable of forming acidic resorption lacunae, and inhibitors of lysosomal acidification attenuated this process. Finally, we measured the response to known bone resorption inhibitors, and found that the osteoclasts were sensitive to these and thereby provided a robust and valid method for interpretation of the effect of antiresorptive compounds. In conclusion, we have established a robust assay for developing osteoclasts that can be used to study several biological aspects of the osteoclasts and which in combination with the resorption marker CTX-I provides a useful tool for evaluating osteoclast function in vitro.
Diabetic Retinopathy: A Quadtree Based Blood Vessel Detection Algorithm Using RGB Components in Fundus Images
Abstract Blood vessel detection in retinal images is a fundamental step for feature extraction and interpretation of image content. This paper proposes a novel computational paradigm for detection of blood vessels in fundus images based on RGB components and quadtree decomposition. The proposed algorithm employs median filtering, quadtree decomposition, post filtration of detected edges, and morphological reconstruction on retinal images. The application of preprocessing algorithm helps in enhancing the image to make it better fit for the subsequent analysis and it is a vital phase before decomposing the image. Quadtree decomposition provides information on the different types of blocks and intensities of the pixels within the blocks. The post filtration and morphological reconstruction assist in filling the edges of the blood vessels and removing the false alarms and unwanted objects from the background, while restoring the original shape of the connected vessels. The proposed method which makes use of the three color components (RGB) is tested on various images of publicly available database. The results are compared with those obtained by other known methods as well as with the results obtained by using the proposed method with the green color component only. It is shown that the proposed method can yield true positive fraction values as high as 0.77, which are comparable to or somewhat higher than the results obtained by other known methods. It is also shown that the effect of noise can be reduced if the proposed method is implemented using only the green color component.
A retrospective study of blood transfusion in dogs from a veterinary hospital in Bangkok, Thailand
Abstract Blood transfusion is the established therapeutic method for anemic human patients and has recently become more practical in veterinary medicine. The objectives of this study were to demonstrate the etiology of anemia, the effectiveness of blood transfusion, and the incidence of transfusion reaction after treatment in dogs. The data of the transfusion veterinary service at the Chulalongkorn Veterinary Teaching Hospital (CVTH) were collected from January 2005 to February 2006. The presentation, causes of anemia, hematology, and transfusion reaction of 41 dogs were summarized as frequency and percentage. The hematology data were continuously analyzed as mean, median, and range. The mean of packed cell volume before and after treatment of all dogs was 11.3 and 26.5%, respectively. The anemic causes of 41 dogs were categorized into three groups including blood loss (43.90%), ineffective erythropoiesis (34.15%), and hemolysis (21.95%). The hematology of three categorized groups was not significantly different. Acute nonhemolytic transfusion reactions were observed in 4.18% of the dogs after transfusion, and they rapidly recovered after treatment. Although transfusion treatment in dogs shows good short-term efficacy, for complete therapeutic results, long-term data need to be gathered.
Caveolins and flotillin-2 are present in the blood stages of Plasmodium vivax
Abstract Blood stages of Plasmodium vivax induce the development of caveolae and caveola–vesicle complexes (CVC) in the membrane of their host erythrocyte. Caveolae are found in almost all types of cells and are involved in endogenous processes as calcium and cholesterol homeostasis, cell signalling, transporting, ligand internalization and transcytosis of serum components. Major structural components of caveolae are the proteins caveolins and flotillins. The functional role of caveolae in the P. vivax-infected erythrocyte is not properly understood. As these organelles have been shown to contain malaria antigens, it has been suggested that they are involved in the transport and release of specific parasite antigens from the infected erythrocyte and in the uptake of plasma proteins. Using specific antibodies to classical caveolae proteins and an immunolocalization approach, we found caveolin-2, caveolin-3, and flotillin-2 in the vesicle profiles and some CVC of P. vivax-infected erythrocytes. Caveolin-1–3 were not found in uninfected erythrocytes. This is the first report of identification and localization of caveolins in the CVC present in erythrocytes infected with P. vivax, thereby providing evidence of the role of this particular organelle in the protein-trafficking pathway that connect parasite-encoded proteins with the erythrocyte cytoplasm and the cell surface throughout the asexual blood cycle of vivax malaria parasite.
Normal cellular morphology of the blood of Japanese quail ( Coturnix coturnix japonica)
Abstract Blood samples were collected from the wing vein of 75 clinically healthy quails (Coturnix coturnix japonica) according to their age (<1 week, 3, 5 and >5 weeks) and sex. The blood smears were stained using the Giemsa, Wright and new methylene blue methods. The result indicated that blood cell morphology in quails is similar to that in chickens and other birds. Age had a significant effect on lymphocyte size (p=<0.05), whereas sex had a significant effect on the width of reticulocytes and small lymphocytes (p =<0.05).
Endothelial Dysfunction and Circadian Blood Pressure Rhythmicity in Young Heart Transplant Recipients
Abstract Blood pressure variability correlates with circadian rhythmicity in endothelium-derived nitric oxide (NO) production in adults. Young, hypertensive orthotopic heart transplant (OHT) patients have functional abnormalities in NO-dependent signaling pathways that lead to reduced NO bioavailability and endothelial dysfunction. Following acute intravenous infusion of L-arginine, the amino acid substrate for NO, OHT patients normalize blood pressure (BP) and endothelial function. However, the effects of chronic L-arginine infusion on circadian BP rhythmicity and endothelial function in OHT patients have not been described. Six OHT patients (9–29 years old), and seven healthy control subjects (19–28 years old) were admitted for 48 hours. Systolic, diastolic, and mean blood pressures (MBP) were recorded hourly. Urine samples were obtained to measure nitrates/nitrites (NOX). Brachial artery flow-mediated vasodilatation (FMD; an index of endothelial function) and left ventricular ejection fraction (LVEF) were measured 0, 23, and 48 hours after admission. Intravenous L-arginine HC1 was infused continuously beginning 24 hours after admission in all subjects. The incidence (50%) and degree (12.0 ± 9.2%) of nocturnal MBP dipping was significantly less in OHT patients than control subjects. Furthermore, FMD was significantly reduced in OHT patients compared to controls (3.2 ± 1.1 vs 7.2 ± 3.1%, p = 0.01). L-Arginine infusion had no significant effect on 24-hour MBP, LVEF, or nocturnal dipping status in any subject; however, L-arginine normalized FMD in OHT patients (7.4 ± 1.8%). Circadian BP variability and endothelial function are impaired in young cardiac transplant patients with medically controlled hypertension, and L-arginine administration reverses endothelial dysfunction.
Blood pressure variability: Its measurement and significance in hypertension
Abstract Blood pressure (BP) fluctuations over time physiologically result from the complex interaction between environmental stimulation, genetic factors, and cardiovascular control mechanisms. Ambulatory BPmonitoring techniques, in particular systems providing beat-by-beat BP recording, have allowed a detailed description of the different components contributing to overall BP variability (BPV) over 24 hours, including short-lasting and more sustained BP changes. In hypertension, BPV increases with increasing BP levels, and evidence is available that its magnitude correlates closely with target-organ damage and with the incidence of cardiovascular events, independent of absolute BP levels. It has been suggested that drugs capable of providing smooth 24-hour BP control, reducing BPV, may confer additional target-organ protection. Mathematic indices, such as the trough-to-peak ratio and the smoothness index, represent useful measures of the homogeneity of the antihypertensive effect over 24 hours. Further studies are still needed to confirm that, in humans, interventions that can reduce BPV can also reduce the rate of cardiovascular events.
Local infusion of norepinephrine reduces blood losses and need of transfusion in total knee arthroplasty
Abstract Blood loss after total knee arthroplasty (TKA) is often associated with cardiovascular complications and a high transfusion rate of allogenic blood. In our study we focused our attention on developing a new intra-surgical procedure that appears safe, easy to perform and effective in the reduction of bleeding in TKA. We evaluated 84 patients who underwent TKA and met our inclusion criteria; they were assigned to two groups: 55 controls in which a saline solution was used to wash the surgical field before tourniquet release, and a second group of 29 patients, in which a saline solution containing a low dose of norepinephrine was locally applied before tourniquet release. The local administration of a low dose of norepinephrine has induced a significant reduction of perioperative blood loss and blood transfusion requirements; in addition, this method was characterised by the absence of complications or adverse effects. In conclusion, our data suggest that intraoperative local administration of a low dose of norepinephrine could represent an effective and safe method of reducing blood loss and preventing blood transfusions in patients with TKA.
Blood flow in the testes and epididymides of male rats with experimental blockade of testicular veins
Abstract Blood flow in reproductive organs was studied during experimental cessation of blood outflow in the testicular vein. This pathological state was accompanied by disturbances of the complex pathogenesis. The major component was autoregulatory focal ischemia, which resulted from the venoarterial response to venous hypertension.
Blood and blood component therapy in neonates
Abstract Blood component therapy is a very common intervention practiced in newborns; nearly 85% of extremely low birth weight (ELBW) babies get transfusions during their hospital stay. However, there are no set guidelines for transfusion of blood component therapy in newborns. This protocol includes available types of blood components, their methods of preparation, indications and side effects of transfusion, in relation to newborns.
Blood chemistry reference values for two ecologically distinct populations of foraging green turtles, eastern Indian Ocean
Abstract Blood chemistry reference values are important to allow the monitoring of the health of individuals and populations. Blood chemistry reference values were obtained from individuals of two ecologically distinct foraging populations of green turtles (Chelonia mydas) in the eastern Indian Ocean. Samples were taken from 51 resident green turtles from Ashmore Reef (a shelf-edge platform reef) with a predominant seagrass diet, and 59 samples were taken from green turtles from Fog Bay, an inshore coastal embayment in the Northern Territory of Australia with a predominant algal diet. Reference values were different between habitats and showed the importance of regional and habitat-specific reference values for green turtles if they are to be used as a diagnostic tool. Green turtles with a diet of seagrass showed higher levels of total protein than turtles of the same size with algal diets. Clinically sick turtles from Fog Bay had significantly higher levels of urea and AST and lower PCV values than healthy turtles from the same population. Newly recruited turtles from Fog Bay also had higher levels of urea and AST compared to other turtles from the same area. Low levels of internal parasites did not affect blood reference values in clinically healthy turtles.
Microanalyzer for biomonitoring lead (Pb) in blood and urine
Abstract Biomonitoring of lead (Pb) in blood and urine enables quantitative evaluation of human occupational and environmental exposures to Pb. State-of-the-art ICP–MS instruments can only analyze metals in laboratories, resulting in lengthy turnaround times, and they are expensive. In response to the growing need for a metal analyzer capable of on-site, real-time monitoring of trace toxic metals in individuals, we developed a portable microanalyzer based on flow-injection/stripping voltammetry (ASV), and validated the system using rat blood and urine spiked with known amounts of Pb. Fouling of electrodes by proteins often prevents the effective use of electrochemical sensors in biological matrices. Minimization of such fouling was accomplished with suitable sample pretreatment and by establishing turbulent flow of blood and urine containing Pb onto the electrode inside the microanalyzer, which resulted in no apparent electrode fouling even when the samples contained 50% urine or 10% blood by volume. No matrix effect was observed for the voltammetric Pb signals, even when the samples contained 10% blood or 10% urine. The microanalyzer offered linear concentration ranges relevant to Pb exposure levels in humans (0–20 ppb in 10% blood samples, 0–50 ppb in 50% urine samples). The device showed excellent sensitivity and reproducibility; Pb detection limits were 0.44 ppb and 0.46 ppb, and % R.S.D. was 4.9 and 2.4 in 50% urine and 10% blood samples, respectively. It gave similar Pb concentrations in blood and urine to those measured by ICP–MS. It offered high throughput (3 min per sample) and economical use of samples (60 μL per measurement) as well as low reagent consumption (1 μg of Hg per measurement), thus minimizing environmental concerns associated with mercury use. Since it is miniaturized, the microanalyzer is portable and field-deployable. Thus, it shows much promise as the next-generation analyzer for the biomonitoring of toxic metals.
Lectin Binding to Mouse Blood Lymphocytes during Tumor Growth
Abstract Binding of FITC-labeled lectins to lymphocytes from intact mice and mice with transplanted Ehrlich carcinoma and CaO-1 ovarian carcinoma was studied by flow cytofluorometry. Specific binding of lectins by mannose and N-acetylgalactosamine was demonstrated. Lectin binding to lymphocytes from animals with tumors decreased by more than 50% in comparison with intact animals. Changed protein glycosylation during tumor growth is specific and differs for tumors of different origin.
Comparative estimation of the “Membrane Reserve” of blood cells of reptiles and mammals
Abstract Based on the method of hypoosmotic loads, the value of membrane reserve and its use by blood cells of reptiles and mammals have been studied. It has been shown that lymphocytes of the both animal species have the highest reserve of plasmalemma, while frog heterophils—the lowest one. A significantly lower part of the membrane reserve participates in formation of phagosomes by mammalian neutrophils as compared with amphibian erythrocytes.
Tuesday, July 22, 2008
Microvascularity, blood flow and tissue structure at the subchondral plate using an X-ray fluorescence technique
Abstract The measurement of blood flow and blood in bone and cartilaginous tissues is crucial to understanding of the development of various diseases, but it presents a formidable technical challenge. We have therefore developed a method based on the detection of metallized microspheres using X-ray fluorescence. This approach provides unrivalled sensitivity and spatial resolution and also allows us simultaneously to measure other markers of the metabolic status of the tissue.
The Blood Supply to the Nipple-Areola Complex of the Human Mammary Gland
Abstract The main sources of blood supply to the breast are described in textbooks as the internal thoracic, lateral thoracic, and posterior intercostal arteries. Textbooks, however, do not describe the contribution of each to the nippie-areoia complex (NAC), nor do they describe the pattern of supply.To investigate this issue, 15 female cadavers were injected intraarterially with latex, and dissections were performed on 27 breasts.
Pulsatile blood pump with a linear drive actuator
Abstract The main purpose of this study was to develop an implantable direct-electromagnetic left ventricular assist system driven by a linear actuator (linear LVAS). The linear LVAS is a pulsatile pump with a pusher plate that is driven directly by a linear oscillatory actuator (LOA) without any movement converters. This prototype pump unit with a LOA was 100 mm in diameter, 50 mm in thickness, and weighed 740 g. The full-fill/full-eject driving method was applied to the control algorithm. In addition, a mechanism to detect and release sucking was realized to overcome this problem that accompanies the active-filling type of VAS. The performance of the linear LVAS was evaluated in a long-term animal experiment using a goat (56 kg). The goat survived for 42 days. The reason why we terminated this experiment was that thrombus was found in the pump. There was no frictional debris found around the LOA. The linear LVAS did not exhibit electrical or mechanical problems during the first animal experiment.
Proline induces alterations in nucleotide hydrolysis in rat blood serum
Abstract The main objective of the present study was to evaluate the in vivo (acute and chronic) and in vitro effects of proline on serum nucleotide hydrolysis. For acute administration, 29-day-old rats received one subcutaneous injection of proline (18.2 (μmol/g body weight) or an equivalent volume of 0.9% saline solution (control) and were sacrificed 1 h, 3 h or 12 h later. Results showed that acute proline administration provoked a decrease in ATP (42%) and ADP (49%) hydrolysis when rats were sacrificed 1 h after the injection. Furthermore, in rats killed 3 h and 12 h after acute injection, no change in nucleotide hydrolysis were observed. For chronic treatment, buffered proline was injected subcutaneously twice a day at 10 h intervals from the 6th to the 28th day of age. Rats were sacrificed 3 h or 12 h after the last injection. Chronic administration of proline did not alter the nucleotide hydrolysis when the rats were killed 12 h after the last injection, but decreased ATP (15%) and ADP (32%) hydrolysis when rats were sacrificed 3 h after the last injection. The in vitro effect of proline (3.0 μM - 1.0 mM) on serum nucleotide hydrolysis was also investigated; results showed that 1.0 mM of proline significantly increased ATP (45%), ADP (55%) and AMP (49%) hydrolysis. The data indicate that proline in vivo and in vitro alters nucleotide hydrolysis, which may be involved in the pathogeny of hyperprolinemic patients.
Instrumental Requirements for Non-Invasive Blood Glucose Measurement Using NIR Spectroscopy
Abstract The magnitude of spectral change in blood glucose measurements with diffuse reflectance spectroscopy is investigated. Spectral change is estimated by simulation of light propagation in skin tissue and measurements of absorbance spectra of aqueous glucose solution. Required sensitivity of spectrophotometers for monitoring change in the blood glucose concentration as small as 10 mg/dL has been obtained using the estimated change in the absorbance spectrum and mean pathlength of light in tissue.
Extraction of the magnetohydrodynamic blood flow potential from the surface electrocardiogram in magnetic resonance imaging
Abstract The magnetohydrodynamic effect generates voltages related to blood flow, which are superimposed on the electrocardiogram (ECG) used for gating during cardiac magnetic resonance imaging (MRI). A method is presented for extracting the magnetohydrodynamic signal from the ECG. The extracted magnetohydrodynamic blood flow potential may be physiologically meaningful due to its relationship to blood flow. Removal of the magnetohydrodynamic voltages from the ECG can potentially lead to improved gating and diagnostically useful ECGs.
Effect of blood passage through the pulmonary circulation on fibrinolytic parameters
Abstract The lung vasculature bed has a unique fibrinolytic potential, which has not yet been completely elucidated. We investigated the effect of blood passage through the pulmonary circulation on the values of fibrinolytic parameters in plasma. Forty-seven patients (16 women, 31 men, mean age 54 years, range 21–67 years) who had undergone elective cardiac catheterization were included in the study. The blood samples were taken simultaneously from the right atrium and the left ventricle. The following fibrinolytic parameters were measured: tissue-type plasminogen (t-PA) antigen and activity, plasminogen activator inhibitor-1 (PAI-1) antigen and activity, and euglobulin clot lysis time (ECLT). No difference was found between the samples obtained from the right atrium and the left ventricle with respect to t-PA antigen: 8.1 (6.7–11.3) vs 8.4 (5.9–11.0)ng/ml; t-PA activity: 92 (5–680) vs 62 (32–696)IU/ml; PAI-1 antigen: 8.4 (5.5–14.3) vs 8.7 (6.2–13.1)ng/ml; and ECLT: 5.5 (4.1–9.1) vs 5.6 (4.1–8.5) 1000/min. In contrast, PAI activity decreased significantly: 7.9 (5.8–10.3) vs 7.4 (6.0–10.4)IU/ml, P 0.01. Patients with and without pulmonary hypertension did not differ in any of measured parameters, either in the right atrium or in the left ventricle. These results show that under basal conditions fibrinolytic activity which is not attributed to t-PA is elevated in lung vasculature. Further, basal fibrinolytic activity in the lungs is not influenced by pulmonary hypertension.
The Transport of Nanoparticles in Blood Vessels: The Effect of Vessel Permeability and Blood Rheology
Abstract The longitudinal transport of nanoparticles in blood vessels has been analyzed with blood described as a Casson fluid. Starting from the celebrated Taylor and Aris theory, an explicit expression has been derived for the effective longitudinal diffusion (D eff) depending non-linearly on the rheological parameter ξc, the ratio between the plug and the vessel radii; and on the permeability parameters and related to the hydraulic conductivity and pressure drop across the vessel wall, respectively. An increase of ξc or has the effect of reducing D eff, and thus both the rheology of blood and the permeability of the vessels may constitute a physiological barrier to the intravascular delivery of nanoparticles.
The Blood Brotherhoods
Abstract The Jungian concept of archetypes when aligned with a developmental perspective provides an important analytical tool. It allows many terrorist acts to be read as capture by the archetype of the Terrible Father as a rebellion against the anima archetype of civilization.
Rational structure of blood vessels
Abstract The issue of the optimal (from the viewpoint of strength) structure of blood vessels of a living organism is considered. It is shown that the angle of packing of muscular fibers in vessels is optimal in terms of strength of arteries.
Lactate concentrations in human skeletal muscle biopsy, microdialysate and venous blood during dynamic exercise under blood flow restriction
Abstract The intramuscular microdialysate lactate concentration during dynamic exercise with various degrees of blood flow restriction and its relation to lactate concentration in skeletal muscle biopsy and venous blood were studied. Nine healthy males performed three one-legged knee extension exercises (Ex 1–3). Blood flow was restricted stepwise by applying supra-atmospheric pressure over the working leg. Microdialysate mean (range) lactate concentrations at the end of the exercise periods were 3.2 (0.5–6.6), 4.4 (1.1–9.8) and 7.9 (1.1–11.6) mmol·l–1 during unrestricted, moderately restricted and severely restricted blood flow respectively. There was a significant correlation between microdialysate and venous lactate concentrations at the end of all three exercise periods. Microdialysate lactate concentration correlated significantly to skeletal muscle biopsy lactate concentration at the end of Ex 1. In conclusion, microdialysate lactate concentration in the working muscle increased step-wise with increasing blood flow restriction. It showed a better correlation to venous than to muscle biopsy lactate, which is possibly partly explained by the characteristics of diffusion between body compartments and differences in time resolution between the methods used.
Sensitivity of human cord blood cells to tetrachloroethylene: cellular and molecular endpoints
Abstract The International Agency for Research on Cancer (IARC) currently lists tetrachloroethylene [perchloroethylene (PCE)] as being carcinogenic in animals. PCE is listed as possibly carcinogenic to humans upon occupational exposure. Human exposure to PCE can produce oesophageal cancer, cervical cancer, non-Hodgkins lymphoma, urinary bladder cancer and leukemia. This work shows that PCE modulates the expression of some genes implicated in cancer induction, cell differentiation, cell-cycle progression, and the survival and clonogenic potential of human cord blood cells. After exposure to the compound, the modulated genes were involved in inflammatory responses as with the mitogen-activated protein kinase 14 (MPK 14), or in tumor and metastasis progression as with the matrix metalloproteinase 17 (MMP 17), in cell proliferation as with c-jun and c-fos, and moreover in the apoptotic process as with interferon alpha-inducible protein (IFI), BAX and BCL-2. Analysis of cord blood cells via flow cytometry showed that PCE treatment induced a statistically significant increase in necrosis after 24 h, while the clonogenicity of Human Colony-Forming Unit-Granulocyte/Macrophage (CFU-GM) and Burst-Forming Unit-Erythrocyte (BFU-E) progenitors did not change. In conclusion, our data showed that PCE affected various pathways involved in cancer induction, but its action on cell proliferation and differentiation is not yet clearly understood.
How does the blood leave the brain? A systematic ultrasound analysis of cerebral venous drainage patterns
Abstract The internal jugular veins are considered to be the main pathways of cerebral blood drainage. However, angiographic and anatomical studies show a wide anatomical variability and varying degrees of jugular and non-jugular venous drainage. The study systematically analyses the types and prevalence of human cerebral venous outflow patterns by ultrasound and MRI. Fifty healthy volunteers (21 females; 29 males; mean age 27±7 years) were studied by color-coded duplex sonography. Venous blood volume flow was measured in both internal jugular and vertebral veins in the supine position. Furthermore, the global arterial cerebral blood volume flow was calculated as the sum of volume flows in both internal carotid and vertebral arteries. Three types of venous drainage patterns were defined: a total jugular volume flow of more than 2/3 (type 1), between 1/3 and 2/3 (type 2) and less than 1/3 (type 3) of the global arterial blood flow. 2D TOF MR-venography was performed exemplarily in one subject with type-1 and in two subjects with type-3 drainage. Type-1 drainage was present in 36 subjects (72%), type 2 in 11 subjects (22%) and type 3 in 3 subjects (6%). In the majority of subjects in our study population, the internal jugular veins were indeed the main drainage vessels in the supine body position. However, a predominantly non-jugular drainage pattern was found in approximately 6% of subjects.
Hollow-fiber blood-dialysis membranes: superoxide generation, permeation, and dismutation measured by chemiluminescence
Abstract The interaction of blood with a material surface results in activation of the body's humoral immune system and the generation of reactive oxygen species (ROS). It has recently become clear that ROS are central to the pathology of many diseases. In this study, we evaluated the superoxide generation, permeation, and dismutation in hollow-fiber dialysis membranes by using 2-methyl-6-p-methoxyphenylethynyl-imidazopyrazinone (MPEC) as a superoxide-reactive chemiluminescence producer and an optical fiber probe to detect the resulting chemiluminescence in the hollow fiber lumen. We measured the superoxide generated when bovine blood leukocytes were brought into contact with dialysis membranes. Superoxide permeation was determined by measuring MPEC chemiluminescence in the hollow fiber lumen using an optical fiber probe. Additionally, superoxide dismutation was evaluated by examining the difference in superoxide permeability for membranes with and without vitamin E coating. Superoxide generation varies for different membrane materials, depending on the membrane's biocompatibility. Superoxide permeability depends on the diffusive permeability of membranes. No marked decrease in superoxide permeability was observed among membrane materials. The superoxide permeability of vitamin E-coated membrane was smaller than that of uncoated membrane. The antioxidant property of vitamin E-coated membranes is hence effective in causing superoxide dismutation.
The influence of the sympathetic innervation on the skin microvascular tone and blood flow oscillations
Abstract The influence of the sympathetic innervation on the tone of resistive vessels and blood flow oscillations was studied using laser Doppler flowmetry and skin thermography in 18 healthy subjects (before and after reflex cold and heat tests and local thermal testing), 42 patients with denervation syndromes caused by median nerve damage, and 10 patients with an acute stage of aseptic inflammation after radius fracture. The blood flow oscillations in the range of neurogenic sympathetic influences (0.02–0.052 Hz) supported by low-frequency sympathetic rhythms are an essential component of neurovascular interrelations. The importance of these oscillations is determined by their contribution to an increase in tissue perfusion owing to a decrease in the peripheral resistance and also by the leveling of drastic changes in blood flow and stabilization of microhemodynamics upon pronounced changes in the stationary tone. The high-and low-frequency (tonic and oscillatory, respectively) sympathetic rhythmic activities are expressed in two ways: (1) a synchronous increase or decrease in their amplitudes and (2) frequency dominance. The reactivity of the vessel smooth muscles is an important factor in maintaining the blood flow oscillations. Denervation decreases the oscillation amplitude in the neurogenic range. Under the conditions of local “inflammatory sympatholysis,” reflex tonic effects, rather than oscillatory ones, of the sympathetic impulses are mainly suppressed. An isolated evaluation of the blood flow oscillations in the neurogenic sympathetic range cannot be a measure of sympathetic activity. In studies on its functional state and evaluation of the neurogenic tone (NT) of resistive vessels, it is necessary to take into account the parameters of both stationary and oscillatory components of the NT.
Influence of the temperature and oversouring of blood on its hemorheological properties
Abstract The influence of the change in the temperature and the acidity of blood on its hemorheological properties has been analyzed. It is shown that, at temperatures lower than 45°C, the temperature dependence of the apparent viscosity of blood at a rate of shear ranging from 0.3 to 50 sec−1 is adequately defined by the Arrhenius model with a viscous-flow activation energy of 13–17 kJ/mole. In the range of pH 6.3–7.6, the oversouring of blood mainly influences the critical shear stress, and the Caisson viscosity depends only weakly on the acid-base equilibrium.
Blood Lead Levels and Increased Bronchial Responsiveness
Abstract The immune system is one of the targets most sensitive to lead toxicity, and the association between lead exposure and serum immunoglobulin E (IgE) has been published. Recent studies also reported that lead caused the development of IgE-mediated allergy. To investigate whether blood lead levels contribute to other allergic conditions, we examined the effect of blood lead on bronchial responsiveness (BR) in the general population. We performed a cross-sectional study with adults aged 19 to 58 years in a Korean community. Blood lead level and the methacholine provocation test were performed. The overall mean blood lead level was 2.9 μg/dl, and the mean BR index was 1.14. The percent of subjects with clinically diagnosed asthma was 21 (4%) and there was no difference in blood lead level with and without asthma. In the multiple regression model, the elevation of blood lead level was related to the increase of BR after adjusting for age, sex, height, smoking status, and the presence of asthma. Blood lead level was significantly associated with increased BR that came from the elevation of the IgE level with lead exposure. Lead may contribute to the increase of asthma and other allergic conditions.
Evolution of blood pressure regulation in humans
Abstract The human propensity for hypertension is a product, in part, of our evolutionary history. Adaptation to climate, first in Africa and then throughout the world, has driven our evolution and may have shaped current patterns of hypertension susceptibility. This article reviews human evolution and the impact of climatic adaptation on blood pressure physiology. Evidence suggests that genetic susceptibility to hypertension is ancestral and was magnified during early human evolution. Furthermore, differential susceptibility among human populations is due to differential selection during the out-of-Africa expansion 30,000 to 100,000 years ago. The most important selection pressure was climate, which produced a latitudinal cline in hypertension susceptibility. Therefore, the current epidemic of hypertension is likely due to new exposures of the modern period (eg, higher salt intake) interacting with ancestral susceptibility. Worldwide populations may differ in susceptibility to the new exposures, however, such that those from hot, arid environments are more susceptible to hypertension than populations from cold environments.
Mathematical modeling of blood circulation system and its practical application
Abstract The human blood circulation system is represented by a nonlinear oscillation system for computer-aided digital modeling in real time scale. A parametric identification problem is formulated and its numerical solution algorithm is designed. A computer-aided blood circulation modeling and identification system is designed. The new approaches to construct real control systems for artificial and auxiliary blood circulation elements are based on neurocomputer technologies.
Hepatic hyperplastic nodules showing stains by portal blood flow: hemodynamics revealed by CTAP and CTHA
Abstract The hepatic hyperplastic nodule associated with idiopathic portal hypertension is classified as portal blood flow and hepatic arterial blood flow dominant types. These nodular lesions are considered attributable to abnormal blood flow in the liver. We describe a rare case of hepatic hyperplastic nodules showing stains by portal blood flow.
Blood pressure in the long-term follow-up of children with hemolytic uremic syndrome
Abstract The hemolytic uremic syndrome (HUS) is the most common cause of acute renal failure (ARF) in young children. Most patients recover from the acute phase of the illness but they may develop arterial hypertension (AH) after many years, even in the absence of signs of renal impairment during short-term follow-up. In this study, we performed casual blood pressure (BP) measurement, 24-h blood pressure monitoring (ABPM), and a Bruce walking treadmill study (ET) in 24 children (aged 5–15 years, 13 males, 11 females) with a history of HUS and normal renal function during follow-up (median 5.8 years, range 1.8–12.4 years). There were 22 children (91%) with prodromal diarrhea associated with HUS and 20 (83%) underwent dialysis during the acute illness. All children had normal casual BP measurement. Of 13 children (54%) with normal ABPM, 5 patients (38%) had an abnormal BP response during the ET study. There were 4 (58%) of the 7 patients with AH by ABPM (29%) and an abnormal BP response during ET. These findings suggest that ET could be a useful means of identifying children with a history of HUS that could be at risk of future AH even if they had normal renal function, casual BP, and ABPM during long-term follow-up. These results should be confirmed with a large prospective clinical study.
Current understanding of optimal blood pressure goals in dialysis patients
Abstract The hemodialysis population is associated with a very low survival rate, with myocardial infarctions and strokes accounting for most of the increased mortality. Recent observational studies demonstrate a paradoxical relationship between increasing blood pressure and increasing mortality. Hypertension treated with antihypertensive medications unequivocally reduces cerebrovascular risk, but demonstration of a survival benefit for cardiovascular mortality has proven more difficult to demonstrate. Increased pulse pressure is caused by inadequate dialysis treatment that increases arterial wall stiffness and afterload, and decreases coronary perfusion. The disproportionate representation of diastolic dysfunction and coronary artery atherosclerosis may explain why increased pulse pressure is associated with higher cardiovascular risk for the dialysis population. Optimum blood pressure control has not been established, due to a lack of prospective studies targeting blood pressure reduction. Opinion-based recommendations are offered, but goals should be individualized based on a complete assessment of prevailing comorbidities and should target normalization of the pulse pressure.
Nonesterified fatty acids in blood pressure control and cardiovascular complications
Abstract The fact that cardiovascular risk factors cluster among individuals with the insulin resistance syndrome strongly suggests a common pathogenetic denominator. For many years, abnormalities of nonesterified fatty acid metabolism have been implicated in the disturbances of carbohydrate and lipid metabolism that characterize the cluster. However, until more recently, evidence implicating fatty acids in the hemodynamic and vascular abnormalities that affect patients with this syndrome was lacking. p] Observations from epidemiological, clinical, and basic science suggest that fatty acids can raise blood pressure and contribute to the development of hypertension. The effects of fatty acids on blood pressure may be mediated in part by inhibition of endothelial nitric oxide synthase activity and endothelium-dependent vasodilation. Fatty acids can also increase α1-adrenoceptor-mediated vascular reactivity and induce vascular smooth muscle migration and proliferation. The adverse effects of fatty acids appear to be mediated in part through induction of oxidative stress. Fatty acids interact with other components of the risk factor cluster, including increased angiotensin II, to synergistically augment oxidative stress in cultured vascular smooth muscle cells. Oxidative stress is implicated in the pathogenesis of insulin resistance, hypertension, vascular remodeling, and vascular complications. A clearer definition of the specific reactive oxygen signaling pathways involved and interventions aimed at altering these pathways could lead to more rationale antioxidant therapy and improved outcomes.
Blood urokinase plasminogen activator system in chronic urticaria
Abstract The evidence gathered has pointed to the fibrinolytic system, which apart from its major role in hemostasis may also be involved in inflammatory and immune processes. To understand better the role of fibrinolysis in urticaria, we measured plasma levels of the urokinase system associated molecules such as urokinase-type plasminogen activator (uPA), its soluble receptor (suPAR; CD87) and an inhibitor, plasminogen activator inhibitor type 1 (PAI-1) activity in chronic urticaria (CU) patients. Plasma was obtained from symptomatic sixteen CU patients (12 females and 4 males) showing positive response to autologous serum skin test (ASST), 28 CU patients with negative ASST (20 females and 8 males) as well as from healthy subjects matched by sex and age. The plasma level of uPA and suPAR antigens, PAI-1 activity did not differ significantly among the three subjects groups. The data obtained suggest that CU patients showing positive response to ASST have plasma profile of the urokinase system-associated proteins, which is not markedly different as compared with CU patients with negative ASST as well as healthy subjects. Our findings have also confirmed the earlier studies, suggesting that systemic fibrinolysis may not be involved in chronic urticaria.
Comparison of blood parameters in degenerative liver disease and liver neoplasia in dogs
Abstract The evaluation of blood parameters is the first step in the diagnosis of liver disease. In many cases the blood parameters indicate only cell destruction or disturbances of liver cell synthesis. It is impossible for one to make a diagnosis by blood parameters only. In our investigation we compared the liver parameters ALT, ALP, GLDH, albumin, bile acid and total bilirubin in dogs with severe degenerative liver disease and in dogs with malignant liver tumours. The aim of our investigation was to find differences between the blood parameters in both liver diseases. We found no significant difference in parameters between degenerative liver disease and liver neoplasia. However, in our investigation, compared with other reports, the mean levels of ALT, ALP, albumin and bilirubin were more often altered in liver neoplasia than in degenerative liver disease. Thus, we conclude that disturbances of liver cell integrity and function occur more often in liver tumours than in severe degenerative liver disease.
Development of the blood-brain barrier
Abstract The endothelial cells forming the blood-brain barrier (BBB) are highly specialized to allow precise control over the substances that leave or enter the brain. An elaborate network of complex tight junctions (TJ) between the endothelial cells forms the structural basis of the BBB and restricts the paracellular diffusion of hydrophilic molecules. Additonally, the lack of fenestrae and the extremely low pinocytotic activity of endothelial cells of the BBB inhibit the transcellular passage of molecules across the barrier. On the other hand, in order to meet the high metabolic needs of the tissue of the central nervous system (CNS), specific transport systems selectively expressed in the membranes of brain endothelial cells in capillaries mediate the directed transport of nutrients into the CNS or of toxic metabolites out of the CNS. Whereas the characteristics of the mature BBB endothelium are well described, the cellular and molecular mechanisms that control the development, differentiation and maintenance of the highly specialized endothelial cells of the BBB remain unknown to date, despite the recent explosion in our knowledge of the growth factors and their receptors specifically acting on vascular endothelium during development. This review summarizes our current knowledge of the cellular and molecular mechanisms involved in the development and maintenance of the BBB.
Repressive/defensive coping, blood pressure, and cardiovascular rehabilitation
Abstract The emotional style of repressive coping in relation to blood pressure and cardiovascular disease has received increasing attention during the past 25 years. Repressive coping describes the capacity to render events and feelings inaccessible to consciousness. Intrapsychic conflicts involving unacceptable wishes, fantasies, and impulses can be hidden from conscious awareness. Repressive (or “defensive”) coping has been associated with elevated blood pressure levels, essential hypertension, and paroxysmal hypertension. Cardiovascular patients who use a repressive style have shown mixed results during recuperation. The repressive coping style is easily assessed with two pencil-and-paper measures, which clinicians could administer. Knowledge that a patient uses repressive emotional coping could help physicians better treat this unique group. For patients recovering from cardiovascular events, intervention styles can be adopted that fit the repressive personality. More research in this area will be a challenge to psychologists and internal medicine specialists.
Effect of serotonin on respiration, cerebral circulation, and blood pressure in rats
Abstract The effects of intravenous serotonin on respiration, cerebral circulation, and blood pressure were examined in narcotized rats. Serotonin rapidly decreased local cerebral blood flow (by almost 30%) and blood pressure. Hemodynamic phenomena were accompanied by sharp changes in the respiration pattern: short-term apnea in all cases. The mechanism of this apnea was related to initial stages in blood pressure changes and had a neurogenic nature.
Clofibrate and dalargin increase luminol-dependent chemiluminescence of mouse blood
Abstract The effects of hypolipidemic drug clofibrate and polypeptide dalargin on activity of the neutrophil peroxidase system in mice were studied using the method of luminol-enhanced chemiluminescence. Clofibrate and dalargin increased the chemiluminescence of mouse whole blood. Their combined use several-fold potentiated this effect. It is expected that combined use of hypolipidemics and polypeptides will open a new trend in the search for stimulators of oxygen-dependent nonspecific immunity.
Effect of diazepam on anxiety, sexual motivation, and blood testosterone in anxious male mice
Abstract The effects of diazepam on anxious behavior, sexual motivation, and blood level of testosterone in the presence of a female were studied in male mice with elevated anxiety. Diazepam produced an anxiolytic effect in novel environment, but was ineffective during social contacts. The drug potentiated the primary sexual interest, but failed to correct exhaustion of sexual motivation. The drug produced no effect on blood testosterone.
Fish arsenic may influence human blood arsenic, selenium, and T4:T3 ratio
Abstract The effects of an arsenic-rich fish diet and selenium (Se) supplementation on blood arsenic (As), Se, and thyroid hormones were studied in 32 women divided into four equal groups. Groups 1 and 4 received 400 μg Se-methionine daily, group 2 received 400 μg selenite daily, and group 3 received placebo tablets for 15 wk. In addition, groups 1–3 increased their fish intake, eating at least three fish dinners weekly. Mean blood Se concentrations (initially 1.68 ± 0.24 μmol/L) increased twofold in the Se-methionine groups (p < 0.0001) and by 32% in the selenite group (p < 0.01). Group means of blood As concentrations increased by 63% (p < 0.01), 50% (p < 0.01), 106% (p < 0.01), and 29% (p < 0.05) in the four groups, respectively. Analyzed As intake from duplicate portions of consumed fish correlated with final blood As concentrations (r=0.85, p < 0.001, n=32). In the group not receiving Se, there was a positive correlation between final blood As concentrations and plasma T4 : T3 ratio (r=0.80, p < 0.02, n=8). Initially, blood As concentrations correlated negatively with both T3 and T4 in plasma, but this correlation disappeared upon Se supplementation. The results demonstrate that increased intake of fish may influence blood As concentrations and that circulating thyroid hormones may be influenced by Se-As interactions.
Blood protein reactions to ablation of capsaicin-sensitive neurons
Abstract The effects of ablation of afferent neurons with neurotoxic doses of capsaicin (150 mg/kg) on protein levels in plasma fractions were studied by polyacrylamide gel electrophoresis in Wistar rats at different times points after administration of capsaicin and in inflammatory reactions induced by zymosan (10 mg/100 g). Administration of neurotoxic doses of capsaicin induced biphasic changes in protein levels in plasma fractions. During the initial period (up to seven days), “acute-type” changes in protein content were seen; at 11–30 days, there were chronic increases in the albumin level with decreases in α1, α2, and γ globulins. Defunctionalization of capsaicin-sensitive nerves 14–30 days before induction of inflammation prevented the “acute-phase” changes in protein contents in the albumin, α1, α2, and β globulin fractions in response to induction of inflammation with zymosan.
Effect of transportation stress on blood and bronchoalveolar lavage fluid components in calves
Abstract The effect of transportation stress on the content of bronchoalveolar lavage (BAL) fluid of 20 male Holstein–Friesian calves, 4–10 months old (mean weight 160 kg) was studied. The calves were healthy and had no previous history of respiratory tract diseases. During a period of 42 days experiment, the calves were kept indoors and were fed alfalfa hay and corn silage ad libitum. After a period of adaptation, on day 21, BAL fluid, blood samples, and nasal swabs were taken from all calves; then, the calves were divided into three groups: experimental (ten calves), which were transported and were deprived of food and water during transportation; control 1 (five calves), which were not transported and had free access to food and water during the 12 h of transportation of the experimental group; and control 2 (five calves), which were not transported but were deprived of food and water for the same time as the experimental group. On day 26, BAL fluid samples and nasal swabs were taken from control group 1. Blood samples were collected simultaneously from all groups at 0, 1, 3, 6, and 12 h of transportation. On days 27, 31, and 42, all previous samplings (BAL fluid, blood, and nasal swabs) were conducted on the experimental group and control group 2. Cytological, biochemical, and bacteriologic examination of BAL fluid and hematological and biochemical examination of blood samples revealed that the number of red blood cells, white blood cells, neutrophils, and the levels of cortisol, packed cell volume, total protein, and fibrinogen significantly increased, but lymphocytes significantly decreased in the experimental group compared with control groups 1 and 2 on the day of transportation (p < 0.05). In addition, regarding BAL fluid content, total cell count, macrophages, neutrophils, and total protein increased in the experimental group (p < 0.05). Pasteurella multocida was isolated from BAL fluid of three calves in the experimental group after transportation. Alteration in BAL fluid components in this study may be due to a depressed efficiency of mucociliary system and/or decreased amount of alveolar spatial surfactant either or both of which may predispose affected livestock to show the presence of P. multocida in bronchoalveolar fluid.
Pathogenesis of salt sensitivity of blood pressure
Abstract The effect of sodium in human blood pressure has been a contentious subject of considerable debate for decades. Nonetheless, it is generally conceded that there is heterogeneity to alterations in sodium and extracellular fluid volume in the blood pressure responses of normal and hypertensive humans. Although there are many forms of experimental and clinical hypertension that are clearly related to abnormalities of sodium handling and metabolism, it has been only the advent of the genetic revolution that has provided critical new insight into the mechanisms involved in many of these conditions. In this review, the clinical manifestations of salt sensitivity and several clinical syndromes associated with abnormal sodium metabolism are discussed, and factors that appear to be involved in many of the clinical abnormalities as well as relevant new insights derived from basic research are elucidated.
Effect of some xenobiotics on oxidative metabolism of human blood neutrophils
Abstract The effect of SO 3 2− , S2−, NO 3 − , and NH 4 + on activity of the peroxidase-hydrogen peroxide system in human peripheral blood neutrophils was studied by the cytochemical method. We showed that the effect of these xenobiotics on neutrophils is similar to that on plants.
Synthesis of HSP70 in blood leukocytes as a marker of stress resistance during adaptation
Abstract The effect of preadaptation to non-damaging emotional stress on the synthesis of HSP70 (stress-limiting factor) in peripheral blood leukocytes was studied in experiments on August and Wistar rats characterized by different sensitivity of the gastric mucosa to stress-induced injury. It was found that preadaptation improves stress resistance of Wistar rats characterized by lower innate resistance to acute mental stress and activates HSP70 synthesis in blood leukocytes. In August rats characterized by higher resistance to acute stress, adaptation reduced the resistance to stress-induced injuries, which was accompanied by the absence of activation of HSP70 synthesis in leukocytes compared to the level observed in nonadapted rats during acute stress. Thus, the intensity of HSP70 synthesis in peripheral blood leukocytes can serve as a marker of changes in animal resistance to acute stress caused by adaptation to non-damaging stress exposures and probably to other environmental factors.
Orientation of Red Blood Cells and Rouleaux Disaggregation in Interference Laser Fields
Abstract The effect of interference laser fields on red blood cells (RBCs) was investigated both theoretically and experimentally. The optical trapping and orientation of individual RBC in interference fringes were observed. It was found that RBC rouleaux undergo disaggregation under the action of interference laser fields. To describe the effect of RBC orientation in interference fringes, we used the equation for torque exerted on a discoid dielectric particle in a gradient light field. The experimental results are in agreement with the predictions of the developed theoretical model.
Effects of intravenously administered human atrial natriuretic peptide on elevated blood pressure during surgery
Abstract The effect of human atrial natriuretic peptide (hANP) on blood pressure (Bp) was evaluated in 11 patients who had elevated systoric Bp of over 150mmHg during surgery. A bolus injection of 50µg or 100µg of hANP decreased Bp with an immediate response by 27.6 ± 3.1mmHg (P < 0.001) or 40.7 ± 4.2mmHg (P < 0.001), respectively, accompanying with tremendously increased urine output. Heart rate and PaO 2 were not altered. Thus, a intravenous bolus injection of hANP is an useful therapeutic tool for the treatment of acutely elevated Bp during anesthesia.(Iwatsuki N, Katoh M, Yasuda A et al.: Effect of intravenously administered human atrial natriuretic peptide on elevated blood pressure during surgery. J Anesth 3: 218–222, 1989)
Dose calcium balanced heparin affect blood gas and electrolyte analysis?
Abstract The effect of calcium-balanced heparin (471896, CIBA CORNING) on blood gas and electrolyte analysis was evaluated, by comparing with that of sodium heparin (Na heparin). One ml of whole blood was collected into a syringe, which contained calcium-balance heparin (Ca balanced heparin) or Na heparin. 122 pairs of blood samples obtained from 15 patients were analyzed for Na, K, ionized calcium (Ca++), total hemoglobin, pH, PCO 2, and PO 2 by an automatic blood gas and electrolyte analyzer, CIBA CORNING model 288. There was a significant difference (P 0.05) in pH, PCO 2, Na, and Ca++ between the two different groups. Ca++ concentration was significantly less in Na heparin group than in Ca balanced heparin group, probably due to more chelation of Ca++ by Na heparin than Ca balanced heparin. The present study suggests that the Ca balanced heparin has minimal effect on the blood gas and electrolyte analysis, and is a suitable anticoagulant for the Ca++ measurement.(Ochiai R, Nagano M: Does calcium balanced heparin affect blood gas and electrolyte analysis? J Anesth 4: 61–65, 1990)
Changes in blood plasma volume in rats during ontogenesis
Abstract The dynamics of blood plasma volume were studied for the first time in rats during ontogenesis. The significance of blood plasma volume is estimated in the transport of physiologically active substances to cells and target organs during development. The blood plasma volume was measured in male and female rats during embryogenesis on day 18 (E18), perinatal development on E21 and day 3 of postnatal development (P3), and postnatal development on P15 and P30. Blood plasma volume was measured using Evans Blue dye method. Body mass was determined in the same animals and correlation was estimated between the blood plasma volume and body mass. The plasma volume increased 1.9-fold from E18 to E21, 1.4-fold from E21 to P3, 2.1-fold from P3 to P15, and 3.4-fold from P15 to P30. The body mass increased 5-fold from E18 to E21, 2-fold from E21 to P3, 2.3-fold from P3 to P15, and 3.2-fold from P15 to P30. The ratio of blood plasma to body mass was the highest on E18 (19%) and decreased twice by E21. This index varied from 5.4 to 4.8% during postnatal development. No sex-related differences in these indices were found in rats. The results obtained make it possible to determine the total content of physiologically active substances on the basis of their plasma concentration and, thereby, estimate the efficiency of secretory organs.
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