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PubMed1981

[Experimental study of new cerebral protective substances--functional recovery of severe, incomplete ischemic brain pretreated with mannitol and fluorocarbon emulsion-- (author's transl)].

Using the "canine model of complete ischemic brain regulated with a perfusion method" in which it is possible to control the degree of blood flow to a cerebral hemisphere via a perfusion pump, the effects of mannitol (which acts as a free radical scavenger) and FC (which has 0.1 micrometer of average particle size and a high oxygen-carrying capacity) on cerebral ischemia were investigated. After pretreatment with the drugs, blood flow was reduced via the pump to 1/10 of the normal flow volume and 1 hr later, return to a normal flow was allowed. Subsequent changes in electrical activity were observed and the effects of the drugs evaluated. In the control group, no recovery of electrical activity was seen, but in the animals treated with either mannitol or FC, incomplete, yet distinct recovery was apparent. In the animals administered with mannitol together with FC, however, marked recovery was evident. These experimental results indicated that a combined administration of FC and mannitol is effective in protecting the brain from cerebral ischemia.

Animals↗
PubMed1981

[Development of new methods in suppressing brain infarction--combined administration of mannitol and perfluorochemicals (author's transl)].

Various therapeutic methods have been attempted for cerebral infarction, but the development of more effective methods is still awaited. We have investigations of the effect of mannitol in preventing the development of cerebral infarction and have reported it effects in clinical cases of operated cerebral aneurysms. In recent years, our attention has been drawn to the so-called red cell substitute, perfluorochemicals (FC), which has a high oxygen-carrying capacity and a small particle less than 0.1 mu. In the present studies, using infarction models in dogs which have previously developed and reported, observations are made on the recovery of brain electrical activity in sever ischemia, suppressing brain swelling following recirculation of cerebral blood flow and protection upon the hemorrhagic brain infarction, due to administration of mannitol or FC. These experimental results indicate that the combined administration of mannitol and FC is effective in protecting the brain from cerebral ischemia.

Animals↗
PubMed1983

Anthropological studies among Pangwalas and Gaddis of Himachal Pradesh, North India.

The present paper is based on the Research Project entitled "Impact of Technological and Economic Development Programme on Bio-Cultural Heritage of Gaddis and Pangwalas Population Groups of Himachal Pradesh". The project was framed after UNESCO/MAB Project Nos. 6 and 12 under UNESCO Programme on Man Biosphere (MAB) and supported by the Department of Science and Technology, Government of India. The population groups under investigation are: 1. Transhumant Gaddis of Bharmour Sub-Tehsil, Chamba District; 2. Settled Gaddis of Kangra District; and 3. Pangwalas of Pangi Tehsil, Chamba District, Himachal Pradesh. The carrying capacity has been calculated for Pangi and Bharmour Sub-Tehsil and it has been observed that in both the places the size of population is beyond the capacity of the land. The pattern of body growth and respiratory functions among Transhumant Gaddis of Bharmour Sub-Tehsil, Chamba District and Settled Gaddis of Kangra District have been studied. Statistically non-significant differences in most of the biological variables have been observed among these groups.

Anthropometry↗
PubMed1981

Chronic granulocyte leukemia with respiratory distress. Efficacy of emergency leukapheresis.

In the absence of preexisting pulmonary disease, progressive respiratory failure caused by leukostasis associated with uncontrolled chronic granulocytic leukemia developed in two patients. The conditions of both patients improved dramatically with aggressive leukapheresis. Clinical improvement correlated with decreased pulmonary wedge pressure, while vascular volume remained constant. Continuous-flow cell separation removed numerous immature myeloid cells, replaced them with oxygen-carrying erythrocytes, and maintained a constant blood volume. The course of these two patients demonstrates the use of continuous-flow leukapheresis in an intensive care unit to reduce leukocyte count and manifestations of leukostasis rapidly, while improving the oxygen-carrying capacity of blood, without exposing the patients to dangerously large shifts in fluid volume.

Emergencies↗
PubMed1982

Correlations between breaking load and CT absorption values of vertebral bodies.

Computed tomography was performed in 25 freshly isolated thoracic and lumbar vertebral bodies of different heights. Their breaking strength was analyzed in a static compression test and compared to the obtained absorption values. It was possible to demonstrate a correlation between absorption values and breaking load which is represented as a logarithmic function. Absorption by cancellous bone in the various vertebrae of one and the same individual was constant. It was dependent upon age. Absorption by cortical bone increased from cranially to caudally and was barely influenced by age in our test material. The sum of the cancellous and cortical absorption values increased from cranially to caudally like the load carrying capacity. The absorption values showed a normal distribution, and the error of reproducibility was approx. 2%.

Absorption↗
PubMed1982

Blood exchange with pyridoxalated and polymerized hemoglobin solution.

A solution of pyridoxalated and polymerized hemoglobin has been used for total blood exchange in the rat to test its effectiveness in vivo. Two groups of eight rats each were transfused to 93 to 95 per cent blood replacement with hemoglobin, control group, or with modified hemoglobin, experimental group, solution. All of the rats in the experimental group survived and became hematologically and physiologically normal at eight days after transfusion, whereas the rats in the control group died at approximately five hours after transfusion. Immediately after transfusion, the circulating fluid in the two groups of rats showed the same oxygen carrying capacity. At three and five hours after transfusion, differences in the oxygen capacity were observed with values in the experimental group of 34 and 103 per cent higher, respectively, than in the control group. The P50 of the vascular fluid in the experimental rats was 47 to 49 per cent greater than the corresponding value in the control group at zero, three and five hours after transfusion. The disappearance of hemoglobin from plasma was faster in the control than in the experimental group with a plasma half-disappearance time of 3.5 and 25 hours, respectively. The differences observed in the rate of disappearance of plasma hemoglobin were reflected in the rate of accumulation of hemoglobin in the urine. A solution of pyridoxalated and polymerized hemoglobin appears to be beneficial in blood replacement, since it promotes survival after massive transfusions.

Animals↗
PubMedDate not supplied

Extracorporeal circulation with perfluorochemicals (Fluosol-DA).

Experimental studies on extracorporeal circulation (ECC) with perfluorochemicals (Fluosol-DA) as a perfusate was performed to examine oxygen carrying capacity and its organ distribution using eight calves. Approximately 80% of the circulating blood volume was withdrawn before ECC and reinfused after completion of ECC. ECC time was 60 minutes in five of the calves and 120 minutes in three of the calves. Hct and Hb decreased to 4-12% and 1.7-6.6 g/dl during ECC. Fct (Fluorocrit: volume percentage of Fluosol-DA) ranged between 5 and 10%. PaO2 and PvO2 were 432-543 mmHg and 93-164 mmHg. Sixty-seven to 86% of the oxygen consumed by the tissues was delivered by Fluosol-DA. One of the complications of ECC with Fluosol-DA, hemolysis was observed in four of the calves which had a relatively high level of Fluosol-DA retention (13.9 g/kg) in the body after ECC. The retention volume of the other four calves which did not show hemolysis was 10.0 g/kg. Retention of Fluosol-DA after ECC was found to be greater in the reticuloendothelial system of the calves sacrificed earlier and became trace or minimal after 10 months.

Alanine Transaminase↗
PubMed1981

[Day care, the day care patient and his partner].

The aim of this contribution is to examine what the consequences are of an admission to a psychogeriatric dayhospital for a patient and his partner. In the first place attention has been payed to some complicating factors: on the one side the organization and function of daycare among other institutions, on the other side, at greater length, the direct care to a patient and his partner. Then, an account has been given of a pilotstudy regarding the experience of a patient and his partner in case of an admission to a psychogeriatric dayhospital. By way of literature research, information from family- and patient-meetings and Grid-data, it has been found that it is significant to involve the family in an over-all treatment, in the first place because family can give relevant supplying information; in the second place because an admission can be problematic to such an extent that a partner needs support too. Besides, the carrying-capacity of the family is of crucial importance in case of a daycare-situation. It was further put that more research has to be done into the psychological processes of an admission.

Adaptation, Psychological↗
PubMed1981

Phlebotomy with iron therapy to correct the microcytic polycythemia of chronic hypoxia.

Patients with chronic hypoxia develop a physiologically appropriate "secondary" polycythemia that improves oxygen carrying capacity. Supplemental iron is often required to maintain this. In severe cases when hematocrit levels approach 70%, iron is withheld in order to avoid dangerously high hematocrit levels and the risks of vascular sludging due to "hyperviscosity." Some patients even require reduction of viscosity by exchange of their polycythemic blood for plasma when symptoms develop. Iron deficiency with microcytic polycythemia can then develop. Management of such patients is unclear. Continued blood withdrawal will worsen the iron deficiency; iron supplementation will increase the hematocrit level and the risks of hyperviscosity. The combination of frequent phlebotomy with oral iron therapy should improve iron stores while safely maintaining a stable hematocrit level in patients with microcytic polycythemia. This combination should also have multiple beneficial effects on tissue oxygen delivery and utilization. This approach has been discussed and used for a patient with microcytic polycythemia due to Eisenmenger syndrome. While on therapy the patient's clinical symptoms decreased, and his serum iron level, hematologic indices, and treadmill tolerance tests all improved.

Administration, Oral↗
PubMed1981

Autosomal Dominant familial erythrocytosis due to autonomous erythropoietin production.

A family is described in which four members spanning three consecutive generations have erythrocytosis associated with a normal hemoglobin oxygen affinity. When bone marrow from one affected family member was cultured in vitro, erythroid colonies formed only when erythropoietin was added to the culture. Serum erythropoietin, measured by radioimmunoassay, was significantly elevated above normal in each of the affected family members. Bioassayable erythropoietin was detected in the urine of two of the three affected family members. In two of the affected family members, erythropoietin was measured in serum by radioimmunoassay and in urine by bioassay before and for 4 days following an isovolemic phlebotomy, which reduced the red cell mass by 20%. Neither serum nor urinary erythropoietin levels changes following phlebotomy. The erythrocytosis in this family appears to be secondary to inappropriately increased erythropoietin production unassociated with a decrease in the blood oxygen-carrying capacity. This is the first instance in which autonomous erythropoietin production appears to be inherited on an autosomal dominant basis.

Adolescent↗
PubMed1980

Massive exchange transfusions with crystalline hemoglobin solution and subsequent replacement of hemoglobin and blood volume.

Crystalline hemoglobin solution was used to exchange transfuse rats to 75 per cent blood replacement. At three hour intervals after transfusion, the rats received bolus injections of hemoglobin solution to replace plasma hemoglobin and intravascular volume lost during each time interval. At 12 and 24 hours after termination of exchange transfusion, the livers of five of six rats exhibited normal hepatic structure. One rat had centrilobular hepatic neurosis similar to that reported for rats given a single transfusion. Plasma hemoglobin, packed cell volume, plasma oncotic pressure and oxygen-carrying capacity of the intravascular fluid were monitored; the data demonstrate that changes observed in these parameters are rectified by the bolus injection which brought their values to the levels observed after transfusion. No hepatic lesions or other abnormalities were observed in the rats in the control group exchange transfused isovolemically with pooled rat blood or subjected to surgical procedures only. Serial bolus injections of hemoglobin solution, by rapidly restoring blood volume and hemoglobin concentration, appear to prevent the hepatic necrosis observed in rats a few hours after a single transfusion, as reported in previous studies.

Animals↗
PubMed1980

Load-bearing mode of the knee joint: physical behavior of the knee joint with or without menisci.

The load-bearing mode of the knee joint and the load-carrying capacity of the menisci were investigated by a load-deflection and load-contact study using stresses of as much as 3 times body weight on 14 freshly amputated knee specimens. A flection angle of 0 degrees was used. The average deflection and the average size of the contact area of the intact knees were 1.04 x 10(-1) cm and 14.1 cm2 respectively when the knees were loaded to 1,500 N. The elastic modulus of the entire joint was 2.7 x 10(2) MPa over the load of 1,500 N. At first, the knee joint was not congruous at a low load under about 500 N; the joint contacts both menisci in conjunction with some part of the exposed cartilage. However, the joint became markedly congruous at higher loads, around 1,000 N. The joint was in contact with the menisci and the exposed cartilage, and as more load was applied, the areas of contact widened to the peripheral areas of both the compartments. After menisci were removed, the deflection increased. The size of the contact areas decreased significantly by a third to a half. Consequently, the average stress increased 2 to 3 times that of the intact knee. The elastic modulus was increased over 2 fold after menisci were removed. The results of the energy study indicate that the menisci gave more elastic stability to the joint. After the menisci were removed, more energy was dissipated during cyclic loading. Thus, the menisci provide surface compliance and serve to transmit stresses across the wider areas to the periphery, and, therefore, help to avoid stress concentration both in the articular cartilage and in the subchondral bone, especially under high loads over 1,000 N.

Adult↗
PubMed1980

The environmental symptoms questionnaire: revisions and new filed data.

The Environmental Symptoms Questionnaire (ESQ) was developed to obtain information about the incidence and severity of symptoms produced by exposure to several different climatic conditions. A subsequent revision is reported here, along with a description of its use in two studies involving physical stresses frequently encountered by military personnel. The first study examined the effects of prolonged flight on the health and physical work performance of men assigned to an overseas station. The second study tested the effects of acute altitude exposure on the load-carrying capacity of men over a period of several days. Five independent symptom factors were identified in the data of the first study, and then were applied to the analyses of treatments of both studies. The factor scores exhibited predictable and meaningful data in both cases. The factors are described, results are compared to previous studies, and general recommendations for use of the questionnaire are made.

Aerospace Medicine↗
PubMed1980

Synthetic erythrocytes from lipid encapsulated hemoglobin.

Synthetic erythrocytes have been formed by encapsulating concentrated hemoglobin solutions in microcapsules consisting of phospholipid-cholesterol mixtures. The microcapsules (hemosomes) are of the order of one micron in diameter or smaller, are osmometers, are somewhat sturdier than erythrocytes (RBC), and are stable upon freezing. They have essentially the same oxygen and carbon dioxide carrying capacity as RBC, and can be tailored to have the same electrokinetic properties. They appear to evoke no immune response in the rat. In experiments involving complete replacement of natural blood hemosomes appear to sustain life. Rats can live and breathe normally without signs of hypoxia or acidosis for extended periods of time after the hematocrit of natural RBC drops well below the critical level. Synthetic erythrocytes do not appear to cause disseminated coagulation, microembolism, or any observable changes in internal organs.

Animals↗
PubMed1995

[Clinical study on the ideal temperature of blood cardioplegic solution in coronary artery bypass graft surgery].

The effect of myocardial protection in coronary artery bypass graft surgery was evaluated from enzymatic examination and cardiac function to clarify the ideal temperature of blood cardioplegic perfusate (BCP). The surgical cases were divided into two groups from the temperature of BCP; 8 degrees C BCP in 64 cases (Group I) and 20 degrees C BCP in 64 cases (Group II). Peak total creatine-Kinase (CK) and CK-MB fraction were significantly elevated in Group I than in Group II. The value of CK-MB was 79 +/- 79 IU/L in Group I and 37 +/- 26 IU/L in Group II (p < 0.01). The parameters of cardiac function were measured from radio-isotope (RI) ventriculography in the 35 cases with depressed ejection fraction and elevated left ventricular end-diastolic pressure (17 cases in Group I and 18 cases in Group II). Postoperative parameters such as ejection fraction, first third ejection fraction, peak ejection rate and early diastolic peak filling rate improved more significantly than preoperative values in Group II, although these parameters did not improve in Group I. From these results, 20 degrees C BCP provided excellent myocardial protection to arrested heart during coronary artery bypass surgery probably because of decreased viscosity of BCP and adequate oxygen carrying capacity to myocardium.

Blood↗
PubMed1995

The cardiovascular effects of sepsis.

Future therapies for septic shock will likely center around the antagonism of toxins released by the infecting organism and the modification of the host response to such toxins. Until such therapies become available, patient salvage will continue to depend on the maintenance of effective circulatory function until the source of infection is eliminated. With the recognition that resuscitation is best directed toward optimization of peripheral oxygen metabolism, reduction of mortality has been achieved in recent years through the early application of invasive hemodynamic monitoring and the aggressive manipulation of the determinants of peripheral oxygen delivery. Volume loading to improve myocardial performance, transfusion to increase the oxygen carrying capacity of the blood, intubation and mechanical ventilation to maximize arterial oxygen saturation, sedation to limit unnecessary peripheral oxygen use, and pharmacologic support of supranormal peripheral perfusion requirements are the essential tenets of successful management.

Cardiovascular Diseases↗
PubMed1995

Exercise and mineral status of athletes: calcium, magnesium, phosphorus, and iron.

Calcium, magnesium, phosphorus, and iron are important to a wide variety of body functions, such as mineralization of bones, serving as cofactors to many enzyme systems, sustaining muscle and nerve excitation, and, in the case of iron, maintaining the oxygen carrying capacity of the blood. Many female athletes consume less calcium than the recommended dietary allowance (RDA). This is of concern because of the need to achieve peak bone mass during adolescence and the possible relationship of poor calcium intake to stress fractures. Athletes appear to have adequate magnesium and phosphorus status. However, those athletes who are on calorie-restricted diets may not be ingesting sufficient quantities of magnesium and possibly phosphorus. Limited data have suggested that magnesium status is indirectly related to strength improvement as well as the incidence of muscle cramps. Acute ingestion of phosphorus (phosphate loading) has been shown to improve aerobic capacity. Iron depletion is common in female athletes but similar to the general population. Iron supplements are of health benefit, but of questionable performance benefit, to those who are iron depleted and nonanemic. To maintain optimal status of these minerals, it is recommended that nutrient rich foods be ingested including dairy products and foods high in heme iron.

Adolescent↗
PubMed1993

Carbon monoxide intoxication.

Carbon monoxide poisoning usually results from inhalation of exhaust fumes from motor vehicles, smoke from fires or fumes from faulty heating systems. Carbon monoxide has a high affinity for hemoglobin, with which it forms carboxyhemoglobin. The resulting decrease in both oxygen-carrying capacity and oxygen release can lead to end-organ hypoxia. The clinical presentation is nonspecific. Headache, dizziness, fatigue and nausea are common in mild to moderate carbon monoxide poisoning. In more severe cases, tachycardia, tachypnea and central nervous system depression occur. When carbon monoxide intoxication is suspected, empiric treatment with 100 percent oxygen should be initiated immediately. The diagnosis is confirmed by documenting an elevated carboxyhemoglobin level. Hyperbaric oxygen therapy is recommended in patients with neurologic dysfunction, cardiac dysfunction or a history of unconsciousness.

Blood Gas Analysis↗