New approaches to an understanding of hemodynamic norms]

Tetrapolar rheography was used to investigate central hemodynamics parameters in a group of 80 healthy subjects aged 25-68. Hyperkinetic, eukinetic and hypokinetic types of circulation were determined by interval distribution according to cardiac index. The proportion of the examinees by their hemodynamic type was: 16.3:63.7:20.0%. In hyperkinetic type the optimal level of average blood pressure was provided by a relatively high cardiac output (CO) and low total and specific peripheral resistance (TPR, SPR). The hypokinetic type of hemodynamics was characterized by a low level of CO and a high value of TPR and SPR. Subjects with eukinetic hemodynamic type were in an intermediate position. It is suggested to take into consideration the hemodynamic type in hypertensive subjects for drug selection and treatment control.     

Significance of persons with different blood groups in the influenza type A epidemic process

To study the susceptibility of persons with different blood groups to influenza A, the presence of infection in a group of young children placed under constant observation for 6 years (1974-1980) and in a group of donors observed during 1979-1980 was studied in different epidemic situations. The susceptibility of the persons under observation to type A influenza viruses was shown to depend both on the blood group of the subjects and on the properties of circulating viruses. Persons with group B (III) blood were more susceptible to the virus at the period when new antigenic variants and serotypes appeared, persons with group O (I) blood were more susceptible to influenza infection at the period of the circulation of virulent strains, while persons with group A (II) blood were more susceptible at the period when less virulent strains circulated. The susceptibility of persons with different blood groups was found to change as changes in the properties of the strains occurred in the process of their circulation.     

Numerical analysis of hemodynamics in spastic middle cerebral arteries

Cerebral vasospasm (CVS) is the most common serious complication of subarachnoid hemorrhage. Among the many factors that are associated with the pathogenesis of CVS, hemodynamics plays an important role in the initiation and development of CVS. Numerical simulation was carried out to obtain the flow patterns and wall shear stress (WSS) distribution in spastic middle cerebral arteries. The blood was assumed to be incompressible, laminar, homogenous, Newtonian, and steady. Our simulations reveal that flow velocity and WSS level increase at the stenosis segment of the spastic vessels, but further downstream of stenosis, the WSS significantly decreases along the inner wall, and flow circulation and stagnation are observed. The hydrodynamic resistance increases with the increase of vessel spasm. Moreover, the change of flow field and hydrodynamic forces are not linearly proportional to the spasm level, and the rapid change of hemodynamic parameters is observed as the spasm is more than 50%. Accordingly, in the view of hemodynamic physiology, vessels with less than 30% stenosis are capable of self-restoration towards normal conditions. However, vessels with more than 50% stenosis may eventually lose their capacity to adapt to differing physiologic conditions due to the extreme non-physilogic hemodynamic environment, and the immediate expansion of the vessel lumen might be needed to minimize serious and non-reversible effects.     

Central Hemodynamic Parameters and Cardiointervalogram Features in Infants during Early Postnatal Adaptation

Central hemodynamic parameters were analyzed in 217 healthy full-term newborns. Echocardiography was performed during the first 6 h after birth; during the periods 6–12 and 12–24 h after birth; and at days 3, 5, and 7 of life. A cardiointervalogram (CIG) was recorded simultaneously. Blood pressure was measured in all newborns. Heart rate variability was estimated with standard methods, and differential criteria determined previously were used to identify three CIG types. The spectral analysis of the slow-wave oscillations was performed within the following ranges of frequencies: high frequencies, >0.15 Hz; low frequencies, 0.04 < 0.15 Hz; and very low frequencies, <0.04 Hz. The healthy newborns showed great individual variations of the cardiac index, which were associated with the hyper-, eu-, and hypokinetic types of hemodynamics, evidencing good adaptive capacity of the body. All groups of newborns had three CIG types, irrespective of the type of hemodynamics. The CIG type frequencies depended on the type of hemodynamics at the time of examination of the newborns. This was explained by different mechanisms regulating blood circulation under basal metabolic conditions during functional changes.     

Analysis and Evaluation of the Functional State of the Cardiovascular System in Cosmonauts during Long-term Spaceflights

Forty-four cosmonauts participating in 28 main long-term (73–438 days) missions on the Mirorbital station performed functional tests with graded physical exercise using a bicycle ergometer. There were two types of this functional load. The cosmonauts that participated in the first eight main missions performed a two-step exercise with a total load power of 1150 W. In the remaining cosmonauts, the exercise was three-step, with a total power of 1350 W. The results obtained during the flight were compared with the results of the same tests performed before the flight, which served as control values for each cosmonaut. To estimate the load tolerance, the heart rate (HR), systolic blood pressure, stroke volume (SV), cardiac output (CO), and cardiac index were analyzed. The data were grouped according to the load, taking into account the type of blood circulation for each group before and during the flight. The ratio between different types of blood circulation was found to change during the flight. The responses to both types of exercises before the flight were less favorable in the cases of the hyperkinetic type of circulation. In these cases, the dominance of the chronotropic function of the heart determined the increase in CO. In the cases of the hypo- and eukinetic types of circulation, the response to the exercise was close to normotonic. In microgravity, irrespective of the circulation type and the exercise, the mechanism of the CO formation changed: the effect of HR was dominant, and there was no increase in SV. Insufficient venous return to the chambers of the heart is the main cause of the decreased response of SV to exercises during spaceflight.     

Different types of circulatory responses to mental tasks

The present study investigated the circulatory responses to two mental tasks. Forty males and females performed a mental subtraction task and a color-word task. During each task, the systolic and diastolic blood pressure, mean arterial pressure, heart rate, stroke volume, cardiac output, and total peripheral resistance were measured as cardiovascular indices for a 5-min baseline, a 5-min task period, and a 10-min recovery period. As for the results, three hemodynamic reactivity patterns were verified: Pattern C, characterized by increased cardiac output and decreased total peripheral resistance; Pattern M, characterized by a moderate increase in both cardiac output and total peripheral resistance; and Pattern V, characterized by increased total peripheral resistance and decreased cardiac output. Also, four response types were found among all subjects: Type 1: cardiovascular responses showed the cardiac pattern for both tasks; Type 2: cardiovascular responses changed between the cardiac pattern and the mixed pattern with a change of tasks; Type 3: cardiovascular responses showed the mixed pattern for both tasks; Type 4: cardiovascular responses changed between the mixed pattern and the vascular pattern with a change of tasks. The comparison between types showed that Type 3 and Type 4 had an elevation in their blood pressure by an increased total peripheral resistance. On the other hand, Type 1 and Type 2 tended to have an increased blood pressure by a rise in their cardiac output. And Type 3 and Type 4 showed higher blood pressure and higher scores on the Type A behavior pattern questionnaire. In conclusion, at least four types of circulation response to the mental tasks existed, with Type 3 and Type 4 having higher blood pressure responses and tending to have an elevated blood pressure by a rise in their total peripheral resistance.     

Changes in the expression of blood-group carbohydrates during oral mucosal development in human fetuses

Abstract. The distribution of blood group carbohydrate chains with antigen A, B, H type 2 chain (A and B precursor), and N-acetyllactosamine (H type 2 precursor) specificity was studied in human oral epithelium from different anatomical regions. These represented various epithelial differentiation patterns such as non-keratinized, parakeratinized, and orthokeratinized stratified squamous epithelium. The material included buccal and palatal epithelium from 20 persons with blood group A or O, gingival, and alveolar epithelium from 10 persons with blood group A or B, and buccal metaplastically keratinized epithelium from nine blood group A, two blood group B, and nine blood group O individuals. The blood group carbohydrate chains were examined in tissue sections by immunofluorescence microscopy. The A and B blood group antigens were detected by human blood group sera, and antigen H type 2 chains and N-acetyllactosamine by murine monoclonal antibodies. Each antigen showed a similar staining pattern in buccal and alveolar epithelium (non-keratinized) which differed considerably from that seen in palatal and gingival epithelium (ortho- and parakeratinized). The expression of blood group antigens A or B and the precursor antigen H type 2 chains in metaplastically keratinized buccal epithelium was found to differ significantly from that seen in normal non-keratinized buccal epithelium. The regional variations demonstrated in cell surface carbohydrates are suggested to reflect differences in tissue differentiation.     

Regional variations of cell surface carbohydrates in human oral stratified epithelium

The distribution of blood group carbohydrate chains with antigen A, B, H type 2 chain (A and B precursor), and N-acetyllactosamine (H type 2 precursor) specificity was studied in human oral epithelium from different anatomical regions. These represented various epithelial differentiation patterns such as non-keratinized, parakeratinized, and orthokeratinized stratified squamous epithelium. The material included buccal and palatal epithelium from 20 persons with blood group A or O, gingival, and alveolar epithelium from 10 persons with blood group A or B, and buccal metaplastically keratinized epithelium from nine blood group A, two blood group B, and nine blood group O individuals. The blood group carbohydrate chains were examined in tissue sections by immunofluorescence microscopy. The A and B blood group antigens were detected by human blood group sera, and antigen H type 2 chains and N-acetyllactosamine by murine monoclonal antibodies. Each antigen showed a similar staining pattern in buccal and alveolar epithelium (non-keratinized) which differed considerably from that seen in palatal and gingival epithelium (ortho- and parakeratinized). The expression of blood group antigens A or B and the precursor antigen H type 2 chains in metaplastically keratinized buccal epithelium was found to differ significantly from that seen in normal non-keratinized buccal epithelium. The regional variations demonstrated in cell surface carbohydrates are suggested to reflect differences in tissue differentiation.     

Flow in tubes and arteries--a comparison

The cardiovascular circulatory system of the human body can be compared with a network of tubes. It consists of a pump and a system of branched vessels. The arteries transport the blood to the periphery in a manner similar to that of a water supply network. It is important to know what kind of forces act upon "fittings", bends and bifurcations. It is also essential to assess whether the flow is laminar or turbulent, attached or separated. The flow should be optimized in such a manner as to minimize the drop in pressure. This means that no additional pressure loss due to separation or turbulence should occur, since such losses increase the pump power requirements. The loss appears in heating and acoustic energy. The necessary understanding of blood flow in human vessels is also of great interest to physicians since it is believed that the local flow behavior of blood determines the formation of atherosclerotic plaques. As in tubing systems, deposits in blood vessels are found close to bends and bifurcations. These deposits lead to impaired cerebral circulation and to myocardial infarction. A partial review of recent research into the details of flow behavior (like separation, stagnation and reattachment points) in bends and bifurcations of arterial models is presented. Studies involving steady and pulsatile flow conditions in rigid and elastic models with Newtonian and non-Newtonian fluids are shown here. The most important differences between blood vessels and tubes are discussed. This modern biofluidmechanical approach of detailed flow examination is compared with the more classical hemodynamic approach considering only gross features such as pressure loss coefficients.     

经颅多普勒超声对脑血管状态与人格特征相关性研究

目的：研究脑血管状态与人格特征的相关性。方法：人格特征应用A 型行为类型量表、艾森克人格问卷（EPQ）对60 名20-35岁青年人群进行问卷调查,并划分出不同类型;脑血管状态应用经颅多普勒超声（TCD）的诊断技术测查60 人的大脑中动脉（MCV）的血流速度来判断脑血管的紧张程度。结果：脑血管紧张组：A 型人格为19 人占59.3%,对照组：A 型人格为3 人占10.7%,以A 型人格占优势（x2 =22.85,P〈0.01）。脑血管紧张组（36.2± 5.8）A 型行为问卷平均得分高于对照组（20.3± 2.4））（t=6.81,P〈0.01）。脑血管紧张组P分、N 分、L分与正常对照组比较,差异无统计学意义（均P＞0.05）;脑血管紧张组E分（内外向）高于对照组,差异有统计学意义（P＜0.05）。四种性格类型相比,外向情绪不稳定型的脑血管紧张组13（40.6%）与对照组4（14.3%）相比所占比例较高（x2 =21.91, P〈0.05）。结论：A 型人格,外向不稳定的人格特征与脑血流速度增快有关,可能是脑血管紧张的诱发因素之一。     

Platelet spreading in diabetes mellitus

In 162 test persons divided into healthy control persons and diabetics of type I and type II the thrombocyte spreading was investigated according to the method of Breddin. Age, sex, degree of seriousness of retinopathy, duration of diseases, present level of blood sugar and HbA1 concentration were taken into account. Spread thrombocyte forms were increasingly found in old age, in diabetics of both types and a close relation to the extent of retinopathy was evident. As diabetic retinopathy became evident and with growing degree of seriousness, spread forms of thrombocytes were increasingly found, so that the increased spreading capacity may be interpreted as a disturbed metabolic and blood vessel situation in diabetes mellitus.     

A new in vitro model to evaluate differential responses of endothelial cells to simulated arterial shear stress waveforms

In the circulation, flow-responsive endothelial cells (ECs) lining the lumen of blood vessels are continuously exposed to complex hemodynamic forces. To increase our understanding of EC response to these dynamic shearing forces, a novel in vitro flow model was developed to simulate pulsatile shear stress waveforms encountered by the endothelium in the arterial circulation. A modified waveform modeled after flow patterns in the human abdominal aorta was used to evaluate the biological responsiveness of human umbilical vein ECs to this new type of stimulus. Arterial pulsatile flow for 24 hours was compared to an equivalent time-average steady laminar shear stress, using no flow (static) culture conditions as a baseline. While both flow stimuli induced comparable changes in cell shape and alignment, distinct patterns of responses were observed in the distribution of actin stress fibers and vinculin-associated adhesion complexes, intrinsic migratory characteristics, and the expression of eNOS mRNA and protein. These results thus reveal a unique responsiveness of ECs to an arterial waveform and begin to elucidate the complex sensing capabilities of the endothelium to the dynamic characteristics of flows throughout the human vascular tree.     

Haptoglobin type and isoantibodies (anti-A and anti-B)

In 582 sera of blood donors of the groups A1, A2, B and 0 the Hp type as well as the anti-A or anti-B isoantibody titres respectively were determined. The frequency distribution of isoantibody titres in serum samples with different Hp-type were compared. As far as the numerical difference of distribution was concerned there was only one significant observation in the group of B alpha--titres of test persons with a different Hp-type. On the basis of these findings the following Hp-type/isoantibody relation can be established: low anti-A or anti-B titres respectively (approximately 1:8) will occur more frequently in persons with the Hp-type 1-1, higher titres (approximately 1:64) are to be found predominantly in persons with Hp2 genes. These findings are in accordance with other results, on the basis of which is was suggested that persons with Hp2 gene product have a higher immunogenic reactivity in comparison to type Hp 1-1.     

Epidemiologic evaluation of the immunologic structure of groups with respect to hepatitis A virus

The members of a newly formed group of persons have been found to be dissimilar in the intensity of their immunity to hepatitis A virus (HAV), the character of changes in the specific antibody level and the time of its retention. In groups with the favorable situation with respect to hepatitis A, the epidemic process takes a latent course. The continuous circulation of the infective agent is ensured by the presence of the asymptomatic and inapparent forms of this infection. Changes in the specific immunostructure of groups with sporadic changes of hepatitis A are directed mainly towards an increase in the proportion of highly immune persons (with the titer of antibodies to HAV exceeding 1:2,000), the number of persons with low and medium antibody levels remaining approximately the same. Under the conditions of the northwestern region, the titer of antibodies to HAV exceeding 1:2,000 in the blood serum ensures the protection of humans from hepatitis A.     

Multivariate analysis for the understanding of typical diabetic hemostasis criteria. 2. Prevalent thrombocytic markers]

Various thrombocyte functions and metabolic criteria were investigated in 309 test persons, among them 198 Patients affected with diabetes mellitus, 67 of type I and 131 of type II as well as 111 healthy control persons. From the variety of these factors an optimal amount was determined by means of the statistical method of multivariance analysis separating both types of diabetes and healthy control persons. In addition to haemoglobin A1 concentration, thrombocyte parameters have been found together with the degree of capillary fragility, adrenalin-induced aggregation, platelet aggregation test and clot retraction, which allow individuals to be assigned diagnostically to various groups of test persons. Thus, thrombocyte functions found in both types of diabetes and normal persons exhibit differences which may contribute to a diagnostic classification.     

Genetic blood markers in arthritic diseases]

In the course of studying patients affected with arthritic diseases (bronchial asthma, sugar diabetes) a relationship between those diseases and the blood groups of the Hp and MN systems was established. Patients with bronchial asthma more frequently than in the controls belonged to the Hp 2-2 type and to blood groups MN and O (I), whereas the patients affected with sugar diabetes are usually of the Hp 2-1 type and belong to the belong to the blood groups MN and A(II). The investigation of patients affected with other diseases having a pathogenesis similar to that of bronchial asthma or of diabetes and the observation of healthy persons after prophylactic inoculations as well as the study of sugar metabolism in healthy persons all confirm the relationship of Hp, MN and ABO antigens with arthritic diseases.     

Fibrinolysis in diabetes mellitus

In 198 diabetic patients of type I and type II and in 111 healthy persons of a control group the activity of fibrinolysis was investigated before and after a venous occlusion test of ten minutes. Spontaneous fibrinolysis was significantly diminished in diabetics of both types in comparison to the control group. A relationship to the degree of seriousness of retinopathy could not be identified in type I. The activity of fibrinolysis decreased in all test persons in old age. In diabetics patients of type II as well as in that age group being more than 56 years old there were smaller activities of fibrinolysis at higher stages of retinopathy. A negative linear correlation of this spontaneous activity of fibrinolysis could be found for the duration of the disease as well as for age. Different forms of diabetic therapy and the sex allowed no influence of the activity of fibrinolysis to be recognized. An increase of the activity of fibrinolysis after congestion could be established in diabetics as well as in the control group. After venous congestion the fibrinolytic activity showed no differences any longer in diabetics and in the control group, with age, duration of the disease and form of therapy being taken into consideration. Before and after venous congestion a negative linear correlation could be revealed between the activity of fibrinolysis and the height of blood sugar level. Therefore, the real blood sugar concentration should be taken into account in evaluating the fibrinolytic activity.     

Belief and Behavior Aspects of the EAT-26: The Case of Schoolgirls in Belize

This study investigates components of eating attitudes in a sample of Belizean schoolgirls and argues for separate analysis of eating beliefs and eating behaviors using the EAT-26 in populations undergoing rapid cultural change. The EAT-26 was utilized in a novel manner, preserving the ethnographic and empirical distinction between belief and behavior components of eating attitudes. Participants included a sample of secondary schoolgirls (n = 80) undergoing acculturative stress. Participants reported more disordered eating beliefs than behaviors. Respondents having higher belief scores than behavior scores were more likely to prefer thinner body build and to be concerned about boys’ assessments of their bodies. Girls with higher behavior scores were less likely to report eating when hungry and stopping when full. In conclusion, discriminant validity was found between attitudinal and behavioral aspects of the EAT-26 as evidenced by face validity and patterns in predicting body image preference and desired weight change. Such a distinction has implications for assessing risk for disordered eating among populations undergoing acculturative stress. Among such populations, while behavioral symptoms might be absent or present in subclinical levels, disordered beliefs associated with psychological distress or potential precursors to eating-disordered behavior might be detected and should be investigated further.     

Long-term course of the cerebral circulatory function after brain irradiation in rats

Long-term evolution of radioisotope indices, evaluating respectively the cerebral blood flow (CBF), the cerebral blood volume (CBV) and the cephalic specific distribution space of iodoantipyrine (delta IAP) of rat, was studied after brain irradiation at 20 Gy. Radioinduced hemodynamic alterations evidenced by this approach are biphasic and support the prominent role of circulation impairment in the genesis of delayed brain radionecrosis.     

The acid phosphatase, aminopeptidase and glutamate dehydrogenase activity in the nodose ganglion neurons in emotional stress]

Cell bodies of cardiovascular receptors localized in the rabbit ganglion nodosum exposed to experimental emotional stress were studied histochemically. Two groups of animals were selected for investigation. Rabbits of one group had almost unchanged arterial pressure and small increase in heart rate under emotional stress, while animals of the other group were characterized by strongly marked disturbances of blood circulation leading to the lethal exit at the end of experiment. Activities of lysosomal enzymes--acid phosphatase and aminopeptidase--in the nodose ganglion neurons of the first group rabbits were found to be on the control level, the activity of mitochondrial enzyme, a glutamate-dehydrogenase, was slightly increased, whereas in the second group rabbits all the enzymes studied were significantly activated. A possible correlation between the metabolic changes found in the neurons and the type of hemodynamic changes is discussed.