Rhythms of enzymatic activity in maternal and umbilical cord blood

The 24-h activity patterns of variouns enzymes were determined in human serum, red blood cells and white blood cells of maternal and umbilical cord blood. Blood was drawn from the brachial vein of mothers and from the umbilical cord within ten minutes after delivery. Corresponding blood specimens were obtained from 83 spontaneous labors, occurring at different hours over a period of 60 days. For each variable (variable=activity of a specific enzyme in one of the blood components) the results were grouped according to delivery hour, forming a 24-h pattern which was analyzed to elucidate time dependency. Five out of six corresponding maternal and fetal variables were similar with regard to pattern and peak time. The activity rhythms of glyceraldehyde-3-phosphate dehydrogenase and glucose phosphate isomerase in red blood cells of mothers and fetuses possessed a significant bimodal pattern. The activity rhythms of the latter enzyme in white blood cells and sera exhibited a significant 24-h period. Hexosaminidase activity exhibited a distinct 24-h rhythm in maternal white blood cells, but no significant rhythm could be detected in the fetal white blood cells. The activity of hexosaminidase showed, identical 24-h patterns in maternal and cord serum when analyzed by best fit cosine, and no significant time-dependency when analyzed by ANOVA.     

Rhythms of enzymatic activity in maternal and umbilical cord blood.

The 24-h activity patterns of various enzymes were determined in human serum, red blood cells and white blood cells of maternal and umbilical cord blood. Blood was drawn from the brachial vein of mothers and from the umbilical cord within ten minutes after delivery. Corresponding blood specimens were obtained from 83 spontaneous labors, occurring at different hours over a period of 60 days. For each variable (variable = activity of a specific enzyme in one of the blood components) the results were grouped according to delivery hour, forming a 24-h pattern which was analyzed to elucidate time dependency. Five out of six corresponding maternal and fetal variables were similar with regard to pattern and peak time. The activity rhythms of glyceraldehyde-3-phosphate dehydrogenase and glucose phosphate isomerase in red blood cells of mothers and fetuses possessed a significant bimodal pattern. The activity rhythms of the latter enzyme in white blood cells and sera exhibited a significant 24-h period. Hexosaminidase activity exhibited a distinct 24-h rhythm in maternal white blood cells, but no significant rhythm could be detected in the fetal white blood cells. The activity of hexosaminidase showed, identical 24-h patterns in maternal and cord serum when analyzed by best fit cosine, and no significant time-dependency when analyzed by ANOVA.     

I and i antigens of human erythrocytes : their detection by means of immunofluorescence technic and their changes during ontogenesis]

I and i antigens were detected by indirect immunofluorescence on human erythrocytes. 80% of the cord blood cells were brightly fluorescent with anti-i, 15% only with anti-I. In adult blood, this ratio is reversed, 2% only of the cells being intensively labelled with anti-i. The percentages characteristic of adult blood are established within the first 8 months of life.     

Cancer and blood coagulation

In human patients, blood coagulation disorders often associate with cancer, even in its early stages. Recently, in vitro and in vivo experimental models have shown that oncogene expression, or inactivation of tumour suppressor genes, upregulate genes that control blood coagulation. These studies suggest that activation of blood clotting, leading to peritumoral fibrin deposition, is instrumental in cancer development. Fibrin can indeed build up a provisional matrix, supporting the invasive growth of neoplastic tissues and blood vessels. Interference with blood coagulation can thus be considered as part of a multifaceted therapeutic approach to cancer. Received 30 November 2005; received after revision 7 February 2005; accepted 8 February 2006     

Comparison of cutaneous hyperemia in cattle elicited by larvae ofBoophilus microplus and by prostaglandins and other mediators

Summary Blood flow has been measured in bovine skin following the injection of tick antigens and a number of pharmacological mediators; including histamine, prostaglandins and slow reacting substance of anaphylaxis. The greates increase in blood flow (20 times normal) was recorded with tick antigens and with prostaglandin F2. This mediator may therefore influence blood flow during immune reactions to ticks and during the rapid ingestion of blood by the ticks.Acknowledgments. This work was supported by the Australian Meat Research Committee. We would like to thank J. M. Gough for her technical assistance.     

L-arginine and pancreatic islet blood flow in anesthetized rats

The aim of the present study was to see if L-arginine, which induces insulin release and is a precursor of the endothelial-derived relaxing factor nitric oxide, affects whole pancreatic and/or islet blood flow. For this purpose, anesthetized male Sprague-Dawley rats were injected intravenously with either saline or L-arginine (25, 100 or 250 mg/kg body weight). All doses of arginine caused a slight increase in blood glucose concentration, while the highest dose (250 mg/kg body weight) also increased insulin concentration. However, no changes in either mean arterial blood pressure, whole pancreatic or islet blood flow could be discerned with any of the doses of arginine used. It is concluded that insulin release is not necessarily associated with an increased islet blood perfusion.     

Cardiovascular-compensatory and decompensatory responses in rats anesthetized with pentobarbital compared to chloralose-urethane

The data presented in these studies suggests that rats anesthetized with pentobarbital are better able to compensate for acute blood loss, but are less able to sustain the compensatory effort during hemorrhagic hypotension than rats anesthetized with chloralose-urethane. However, following reinfusion of shed blood the pentobarbital rats are better able to maintain their blood pressure.     

The effect of urethane and pentobarbital anaesthesia and hepatic portal vein catheterization on liver blood flow in the rat

Summary The effect of urethane and pentobarbital anaesthesia and hepatic portal vein catheterization on liver blood flow was investigated in the rat. Liver blood flow with pentobarbital anaesthesia was 40% greater than with urethane. Hepatic portal vein catheterization had no effect under pentobarbital anaesthesia whereas it produced an 18% fall in liver blood flow with urethane.Acknowledgments. This work was supported by grants from ICI Pharmaceuticals and Mersey Regional Health Authority (Research Scheme No. 338). We wish to thank Mr P.J. Roberts for much skilled assistance and Evans Medical Ltd for the kind gift of drugs.     

Correlation between the regional blood volume and epileptic seizures in Papio papio]

The method of labelling red cells with technetium-99m was used to measured regional blood volume auring different types of epileptic seizures induced in the Baboon Papio papio. During seizures the cerebral blood volume increases and there is simultaneously a decrease of blood volume in nasal and hepatic regions, and a transitory increase of blood volume in the forepaws.     

Preliminary purification and dosages of the erythropoietic factor from ox-spleen.

The administration of ox-spleen homogenate, whether in rats made polycythemic by blood transfusion or in mice polycythemic by hypoxia, elicited a significant stimulatory effect on the rate of erythropoiesis. This activity remained unchanged even if the spleen, before being homogenized, was exhaustively washed with isotonic buffer pH 7.4 up to the total blood elimination.     

Blood pressure lowering effect of eicosapentaenoic acid-rich diet in normotensive,hypertensive and hyperlipemic subjects

Summary A mackerel diet or a herring diet in which two cans of fish fillet were consumed daily over 2 weeks within a prescribed regimen, in a crossover design, were given to 15 normotensive volunteers, 14 patients with mild essential hypertension and eight patients with type IV and V hyperlipoproteinemia (HLP). In normotensives a markedly lower systolic and diastolic blood pressure at the end of the period on the mackerel diet could be observed, whereas in hypertensive and hyperlipemic subjects only systolic blood pressure was significantly decreased. After the herring diet, which served as control, changes in blood pressure were of a minor degree.     

Blood pressure lowering effect of eicosapentaenoic acid-rich diet in normotensive, hypertensive and hyperlipemic subjects

A mackerel diet or a herring diet in which two cans of fish fillet were consumed daily over 2 weeks within a prescribed regimen, in a crossover design, were given to 15 normotensive volunteers, 14 patients with mild essential hypertension and eight patients with type IV and V hyperlipoproteinemia (HLP). In normotensives a markedly lower systolic and diastolic blood pressure at the end of the period on the mackerel diet could be observed, whereas in hypertensive and hyperlipemic subjects only systolic blood pressure was significantly decreased. After the herring diet, which served as control, changes in blood pressure were of a minor degree.     

Determination of certain physical and chemical characteristics of the activating serum factor from preparturient women and women with habitual abortions

Summary Follow-up investigation of the blood sera from preparturient women and women with habitual, abortions showed the presence of a factor which has an activating effect on smooth muscle preparations because it causes the release of prostaglandins. Gel-chromatographic counter flow separation and microelectrophoresis of the blood sera have shown that the isolated serum factor is a water soluble glycopeptide with a molecular weight of about 2000.     

Presence of the H blood group antigen on a carcinoembryonic antigen (CEA). Enzymatic transformation of H to A and B specificities]

The carcinoembryonic antigen (CEA-M) was purified from a hepatic metastasis obtained from a blood group O patient with a cancer of the rectum. Using 125I-labelled-CEA and blood group antisera, H specificity was found on the CEA-M; the addition of anti-H to anti-CEA does not modify the binding of labelled-CEA-M to its antibodies (86%), this result leads us to conclude that H and CEA determinants are carried by the same molecule. However the low percentage of binding (30% with 1/10 anti-H) suggests that only a few CEA-M molecules do carry the H antigenic determinant. Finally, glycosyltransferases were used to modify the H specificity into blood group A and B specificities.     

Determination of certain physical and chemical characteristics of the activating serum factor from preparturient women and women with habitual abortions

Follow-up investigation of the blood sera from preparturient women and women with habitual abortions showed the presence of a factor which has an activating effect on smooth muscle preparations because it causes the release of prostaglandins. Gel-chromatographic counter flow separation and microelectrophoresis of the blood sera have shown that the isolated serum factor is a water soluble glycopeptide with a molecular weight of about 2000.     

The effect of nicotine on blood pressure in the genetically hypertensive mouse

Summary Mice genetically selected for high and low blood pressure were exposed to nicotine via a single injected dose or addition to drinking water for 52 weeks. In the acute study, the response of mice with high blood pressure was a statistically significant increase in blood pressure. In the chronic study the pattern of response to nicotine ingestion was similar for mice with high blood pressure and those with low. Both lines responded with an increase in blood pressure after 6 weeks followed by a decrease to below baseline blood pressure at 12 weeks.This research was supported in part by an allocation from the General Research Fund of the University of Kansas.     

Relations between magnesium, erythrocyte zinc and HL-A groups]

Red blood cell and plasma magnesium and zinc levels and plasma calcium concentrations have been determined in 84 unrelated male subjects, with known HLA groups. When the subjects are classified according to their HLA--B groups, significant variations are observed for red blood cell magnesium and zinc concentrations, while no important variation is observed for HLA--A groups. These results confirm the importance of genetic factors in the regulation of Mg and Zn red blood cell concentrations.     

Effect of sympathectomy on platelet aggregation and blood coagulation in rats

Summary It is shown that the ability of blood platelets to aggregate in partially and completely sympathectomized rats is significantly lower than in intact animals. The blood clotting system of sympathectomized rats is hyperactive. The sympathectomy-provoked changes may be due to the increased content of adrenaline in the blood.     

Neurovascular development and links to disease

The developing central nervous system (CNS) is vascularized via ingression of blood vessels from the outside as the neural tissue expands. This angiogenic process occurs without perturbing CNS architecture due to exquisite cross-talk between the neural compartment and invading blood vessels. Subsequently, this intimate relationship also promotes the formation of the neurovascular unit that underlies the blood–brain barrier and regulates blood flow to match brain activity. This review provides a historical perspective on research into CNS blood vessel growth and patterning, discusses current models used to study CNS angiogenesis, and provides an overview of the cellular and molecular mechanisms that promote blood vessel growth and maturation. Finally, we highlight the significance of these mechanisms for two different types of neurovascular CNS disease.