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PubMed2006

Circulating blood volume determination using electronic spin resonance spectroscopy.

There have been numerous methods proposed to measure the circulating blood volume (CBV). Nevertheless, none of them have been massively and routinely accepted in clinical diagnosis. This study describes a simple and rapid method, on a rabbit model, using the dilution of autologous red cells labeled with a nitroxide radical (Iodoacetamide-TEMPO), which can be detected by electronic spin resonance (ESR) spectroscopy. Blood samples were withdrawn and re-injected using the ears' marginal veins. The average CBV measured by the new method/body weight (CBV(IAT)/BW) was 59 +/- 7 mL/kg (n = 33). Simultaneously, blood volume determinations using the nitroxide radical and (51)Cr (CBV(Cr)) were performed. In the plot of the difference between the methods (CBV(IAT) - CBV(Cr)) against the average (CBV(IAT) + CBV(Cr))/2, the mean of the bias was -1.1 +/- 6.9 mL and the limits of agreement (mean difference +/-2 SD) were -14.9 and 12.7 mL. Lin's concordance correlation coefficient p(c) = 0.988. Thus, both methods are in close agreement. The development of a new method that allows a correct estimation of the CBV without using radioactivity, avoiding blood manipulation, and decreasing the possibility of blood contamination with similar accuracy and precision of that of the "gold standard method" is an innovative proposal.

Animals↗
PubMed2001

Studies on improved model for cerebrovascular blood circulation.

For the elastic cavity model adopted in the existing cerebrovascular hemodynamics analyzers was too simple, we developed the improved model for cerebrovascular blood circulation to describe more exactly the physiologic nature of both sides cerebrovascular blood circulation and the relation between them (Willis Circle). It was a network consisting of 2 inputs, 9 arteries and 4 terminal flow resistances. For two cases, constant flow and pulsating flow, the further improved models for calculability were analyzed and the mathematical equations describing the model was obtained; some algorithms were given to solve the positive and negative problems to the mathematical functions; the physiologic means to parameters in the model were defined; at last, the possible applications of the models in basic research and clinic about cerebrovascular disease were stated as well. In the paper, we compared our portable cerebrovascular hemodynamics analyzer with the improved model to other analyzers with the elastic cavity model, and concluded that because of providing additional M-style ultrasonic detector for measuring the diameters of blood vessels and improving the Doppler ultrasonic detector for measuring the velocity of blood flow of the internal carotid artery we could accept the improved model to obtain more exact and more details and the relation about cerebrovascular blood circulation and hemodynamics.

Algorithms↗
PubMed1989

[Effects of nicotinate ethyl ester treatment on gingival blood circulation of experimental gingivitis in monkeys].

The effects of nicotinate ethyl ester treatment on the gingival blood circulation of plaque induced inflammation in monkeys were determined. The blood flow, amount of hemoglobin and oxyhemoglobin rate (oxyhemoglobin/total hemoglobin) in gingival blood circulation in addition to bacterial colony forming units (CFU), gingival index (GI), probing depth (PD), loss of attachment (LA) and amount of gingival crevicular fluid (GCF) were used as parameters. Besides 1% nicotinate ethyl ester paste (nicotinate paste), 0.5% chlorhexidine (CHX) paste as an antibacterial agent, a mixture of the two pastes and the base alone as a control were used. 1. The blood flow, amount of hemoglobin, CFU, GCF, PD and GI increased as inflammation developed, and these showed significant correlations. 2. The oxyhemoglobin rate showed no corresponding change with inflammation. 3. Nicotinate paste, CHX paste and the mixed paste seemed to reduce the inflammation of the gingiva as assessed by the blood flow, hemoglobin amount, CFU and GCF amount compared with the control paste.

Animals↗
PubMed2006

[Clinical evaluation of therapeutic effects of "Cooling the blood and invigorating blood circulation" method on hepatitis hyperbilirubinemia].

BACKGROUND: To explore the effect of treating hepatitis hyperbilirubinemia with Chinese traditional "cooling the blood and invigorating blood circulation" method. METHODS: Seventy-two patients were randomly divided into two groups. The control group (n=36) was treated with hepatocyte growth factor (HGF) 80-120 mg daily on the basis of routine western medicine treatment. The therapy group (n=36) was treated with "cooling the blood and invigorating blood circulation" decoction on the basis of routine western medicine treatment. After using the medicine for 28 days, alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TBIL), albumin (ALB) in plasma were measured to compare the effects of the two methods. RESULTS: The effective rate of the therapy group was 80.55%, that of the control group was 50%. There was significant difference in efficacy between the two groups (P<0.05). CONCLUSION: "Cooling the blood and invigorating blood circulation" method may be effective and safe in the treatment of hepatitis hyperbilirubinemia.

Adult↗
PubMed1991

The use of immobilized protamine in removing heparin and preventing protamine-induced complications during extracorporeal blood circulation.

Heparin, currently used in extracorporeal blood circulation procedures, may lead to hemorrhagic complications. Protamine, used for reversal of heparin-induced anticoagulation at the end of such procedures, can cause adverse hemodynamic responses. To prevent both types of complications, we have developed a reactor device containing immobilized protamine (i.e., a protamine bio-reactor) that can be placed at the distal end of the circuit, thus providing simultaneous extracorporeal heparin removal and protamine treatment. In preliminary in vivo studies involving dogs at a blood flow of 100 ml/min, the bio-reactor removed about 50% of the administered dose of heparin (i.e., 100 units/kg) in 10 min. While rapid injection of protamine in dogs anticoagulated with heparin produced a transient and significant (P less than 0.005) decreases in systemic arterial blood pressure (-39.5 +/- 9.2 mmHg), cardiac output (-1.59 +/- 0.23 L/min), and mixed venous oxygen saturation (-7.5 +/- 1.3%) and increases in pulmonary artery systolic (+12.7 +/- 4.4 mmHg) and diastolic pressures (+10.0 +/- 3.6 mmHg), the use of the protamine bio-reactor did not elicit any statistically significant change in any of the variables measured. Hemolysis was not significant, as reflected by a statistically insignificant change of the animals' red blood cell counts, hematocrits, and total hemoglobin values. In addition, hemolytic complement was found to be reduced only by 10% in animals with the protamine bio-reactor, whereas it was reduced rapidly by 20% in animals receiving intravenous protamine administration and progressively by 20% in control animals with a sham reactor that contained no protamine. Furthermore, the use of the protamine bio-reactor also significantly reduced the protamine-induced transient thrombocytopenic and granulocytopenic responses. The white blood cell counts and platelet counts decreased to 87.7 +/- 7.5 and 83.3 +/- 5.0% of baseline, respectively, in dogs with the protamine bio-reactor compared to 35.5 +/- 14.3 and 32.1 +/- 8.1% of baseline in dogs receiving intravenous protamine. The protamine bio-reactor may provide a unique means to simultaneously control both heparin- and protamine-induced complications.

Animals↗
PubMed1983

New method to quantitate clonogenic tumor cells in the blood circulation of mice.

A bioassay method to quantitate "clonogenic" tumor cells released into the blood circulation from murine primary tumors is described. The method uses preirradiation of the thorax of the tumor-bearing mice, followed 22 hr later by preparation and culture of a lung cell suspension which contains filtered tumor cells from the blood. The malignant cells form colonies. Our results indicate that the number of "clonogenic" tumor cells in the blood circulation can be quantitated efficiently using only a few mice. This is a major advantage, since previous studies were limited by small amounts of available blood and somewhat uncertain techniques for identification of blood-borne tumor cells. The present method allows us to evaluate "clonogenic" tumor cells and tumorigenicity, which microscopical identification of tumor cells after filtration of a small amount of blood does not permit.

Animals↗
PubMed2006

The effect of passive foot flexion on blood circulation in sports and clinical medicine.

UNLABELLED: The aim of the study was to analyze the effect of the passive foot flexion on peripheral and systemic blood circulations in the state of rest of persons adapted to endurance physical loads, and on patients during surgery. METHODS: In the first series of experiments which included 16 males in recumbent supine position adapted to endurance physical loads, the effect of the passive foot flexion by applying a leg muscle activator on the systemic and peripheral blood circulations was analyzed. In the second series of experiments conducted with 6 males and 12 females, the passive foot flexion was aimed at preventing thromboembologenesis during the intraoperative period. RESULTS: After a session of the passive foot flexion applied to persons adapted to endurance physical loads, the venous reserve volume in them increased to 1.68+/-0.3 mL/100 mL (p<0.05). The maximal venous emptying rate increased to 48.3+/-8.8 mL/100 mL/min (p<0.05). After 15 min of the passive foot flexion, the indices of the systemic blood circulation were analogous to the ones before passive foot flexion. The maximal venous emptying rate in the calves of the left and right legs at the end of the surgery decreased to 59.7+/-4.7 mL/100 mL/min (p>0.05) and to 62.9+/-4.0 mL/100 mL/min (p>0.05), respectively. CONCLUSIONS: The passive foot flexion applied to persons adapted to endurance physical loads increases venous reserve volume and maximal venous emptying rate. During the intraoperative period, the passive foot flexion increases maximal venous emptying rate from the triceps muscle of the calf thus decreasing the possible danger of thromboembologenesis.

Adult↗
PubMedDate not supplied

[Blood circulation in the lungs during prolonged occlusion of the principal branches of the pulmonary artery and following restoration of their patency in experimental conditions].

The results of experiments on 36 dogs showed that in a lung with a ligated pulmonary artery the vascular network is maintained and the circulation of blood occurs through the bronchial arteries and their anastomoses with the pulmonary artery. The blood flow and total vascular bed increase in a functioning lung and the pulmo-arterial resistance diminishes. Desobliteration of the pulmonary artery leads to restoration of the main blood flow in it and the gas-exchange function of the lung which had been operated on, and to normalization of hemodynamics in the contralateral functioning lung.

Animals↗
PubMed1993

[Ibn al-Nefis--discoverer of pulmonary blood circulation].

Medicine was developed to an astonishingly high degree by Muslims. During at least five centuries Muslim physicians translated medical books from Greek and other languages, and with their descriptions of the clinical signs of many illnesses, many of the ideas and concepts contained in medical encyclopedias (like al-Qanun written by Avicenna), passed it to the West and East. One of the greatest Muslim physician was undoubtedly Ibn al-Nefis (d.1288), who first accurately described the circulation of blood through the lung (in XVI century the credit went to Michel Servet), and body (in 1628 the credit went to W. Harvey), and author of the famous Excerpt of al-Qanun, written by Avicenna.

History, Medieval↗
PubMed2003

The presence of human papillomavirus type 16/18 DNA in blood circulation may act as a risk marker of lung cancer in Taiwan.

BACKGROUND: Lung cancer is the leading cause of cancer death in Taiwan, and the paucity of dependable risk markers has impeded the early management of lung cancer. An association of human papillomavirus (HPV) 16/18 infection with lung cancer among nonsmoking Taiwanese women was revealed in our previous study. METHODS: Nested PCR was employed to detect HPV 16/18 DNA in the blood circulation of 149 lung cancer patients and 174 noncancer controls. In addition, correlation of prevalence of HPV DNA between the blood circulation and lung tumor tissue was compared from 70 sets of paired tumor tissues and peripheral blood samples available. RESULTS: The results showed that the prevalence rate of HPV 16/18 in the blood circulation of lung cancer cases was significantly higher than that of noncancer controls (47.7% vs. 12.6% for HPV 16, P < 0.0001; 30.9% vs. 5.2% for HPV 18, P < 0.0001). A significantly higher HPV 16 prevalence was detected in female lung cancer patients than that of male (57.6% vs. 41.1%, P = 0.048), as well as in cases with tumor Stages III/IV than those with tumor Stages I/II (54.6% vs. 29.3%, P = 0.006). After adjusting the effects of age, gender, and smoking status, a 6.5-fold greater risk of lung cancer was demonstrated for those subjects with HPV Type 16 positive (95% CI 3.7-11.3, P < 0.0001), a 9.2-fold for HPV Type 18 positive (95% CI 4.2-20.2, P < 0.0001), and a 75.7-fold greatest risk for those with both HPV Type 16 and 18 positive (95% CI 9.8-582.1, P < 0.0001). CONCLUSIONS: These results suggested that the presence of HPV DNA in the blood circulation may serve as a feasible risk marker of lung cancer.

Aged↗
PubMed1986

Blood circulation in the urethra during hypovolemia--an experimental study.

The changes in urethral blood circulation caused by hypovolemia were studied in male piglets to simulate the hemodynamic changes during extracorporeal perfusion used in open-heart surgery. Changes caused by mild pancreatitis were studied which produced a similar reduction in urethral blood flow measured by microspheres comparable to a 34% hemorrhage of the circulating blood volume. According to this study the urethral mucosa is very sensitive to hemodynamic changes. It may be the case that catheter toxicity is more significant when the urethral blood flow is diminished.

Animals↗
PubMedDate not supplied

[Effect of space flight factors on the blood circulation function in primates].

Using radioactive isotopes, central, peripheral and organ blood circulation was investigated in two rhesus-monkeys before the 7-day space flight, 1.5 hours after touchdown, and 4 months after recovery. Blood distribution and shifts were measured in different body segments, viz. head, chest, abdomen, legs. Postflight measurements revealed a decrease of plasma and blood volume. They also demonstrated changes in cardiac output and stroke volume, decrease of total peripheral resistance, reduction of mean arterial pressure and a slight increase of heart rate. Pulmonary blood flow velocity and time varied insignificantly and in a different manner. Blood was pooled in the legs. Blood flow velocity in the skin of the upper and lower body decreased while in muscles it increased above the baseline values. Postflight, muscles acted as a hemodynamic blood pool. The tolerance of both monkeys to the tilt test was satisfactory. It can be concluded that the monkeys tolerated the 7-day space flight well enough.

Animals↗
PubMed1982

A partially degraded form of human plasminogen in circulating blood.

A method for separate measurement of the amounts of the native form and partially degraded form of plasminogen and plasmin in human circulating blood was devised based on their different mobilities on disc polyacrylamide gel electrophoresis. The relative amounts in the circulating blood as estimated by the method were as follows: 78.5% native form, 6.1% partially degraded form and 15.5% plasmin, in the resting state of healthy adults. The partially degraded form increased to about 50% after strenuous exercise load. The present study showed that relatively large amounts of the partially degraded form can be produced in the circulating blood, even though abundant plasmin inhibitors exist there. These data suggest that the partially degraded form may play an important role in thrombolysis in vivo.

Electrophoresis, Polyacrylamide Gel↗
PubMed1980

[Change in circulating blood volume during prolonged pentamine-induced ganglionic blockade without hypotonia in surgery of gastrointestinal hemorrhage].

The investigation of the volume of the circulating blood in 129 patients operated for gastro-intestinal hemorrhage has shown that by the end of the operation there was an increasing deficiency of the circulating blood volume and HO in spite of hemotransfusion therapy. The use of prolonged ganglionic blockade resulted in the increased circulating blood volume and HO in patients by the end of operation at the expense of redeposition of blood.

Adult↗