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Zwart A - - 1990
Spectral differences between hemoglobin derivatives from adult-(HbA) and fetal-hemoglobin (HbF) make the accurate determination of carboxyhemoglobin (COHb) troublesome in blood of newborns. Only the newest dedicated instruments for the determination of COHb take these differences into account. However, since there are virtually no spectral differences between both hemoglobins in the ...
Nagai M - - 1990
Absorption spectra of erythrocyte hemolysate from a normal subject, the Hemoglobin (Hb1) M Saskatoon patient and the Hb M Boston patients were investigated. Difference spectrum between the hemolysate from either freshly obtained or 37 degrees C-incubated blood of the Hb M Saskatoon patient and that of the normal blood suggested ...
Labotka R J - - 1990
Hb Mizuho [beta 68(E12)Leu----Pro] was identified in a child of Italian/Sicilian descent who exhibited severe, transfusion dependent hemolytic anemia which improved following splenectomy. The patient's peripheral blood smear, which prior to splenectomy demonstrated coarse erythrocytic basophilic stippling, showed large, dense erythrocytic hemoglobin inclusions following splenectomy. Whole blood oxygen equilibrium results ...
Rabinovici R - - 1989
To improve the outcome of trauma victims and of patients undergoing high-blood-loss surgical procedures and to avoid the many serious complications of blood transfusion, there is a need for an oxygen-carrying blood substitute. Synthetic erythrocytes composed of liposome-encapsulated hemoglobin (LEH) represent one of the significant research efforts in this direction. ...
Gibbons I - - 1989
We describe an immunoassay system suited to patient-side assay of therapeutic drugs and blood proteins. The system consists of an electronic monitor and single-use plastic cartridges containing dry reagents and liquid diluents. The monitor is turned on by insertion of a cartridge. To run the test, the user applies an ...
Lundsgaard-Hansen P - - 1989
The different versions of autologous blood transfusion have rekindled interest in a generally valid 'minimum acceptable hemoglobin concentration' of patients around or below 10 g Hb/dl. The adequate Hb concentration capable of covering the oxygen demands of the body depends on several variables measurable at the bedside: oxygen consumption VO2, ...
Bartels P C - - 1989
Direct measurement of the zinc protoporphyrin:haemoglobin ratio (ZPP:Hb ratio) in blood samples is performed by using a haematofluorimeter. Interference by non-specific fluorophores can be eliminated by removing the plasma and making the measurement on washed red blood cells (RBCs). After re-suspending RBCs in isotonic saline, haematofluorimeter readings for the ZPP:Hb ...
Mairbäurl H - - 1989
Oxygen transport by erythrocytes was studied in eight patients on maintenance hemodialysis before, during and after a 2-week stay at an altitude of 2000 m. Dialysis was continued at that altitude. In all tests, blood samples were collected one or two days following hemodialysis. Pre-altitude tests: The patients exhibited anemia ...
Linnik M D - - 1989
Electrically stimulated neurogenic vasodilation and endothelial-dependent cholinergic vasodilation in cerebral arteries are both blocked by hemoglobin. To determine if neurogenic vasodilation has a cholinergic component, we examined the effect of hemoglobin on neurogenic responses and perivascular cholinergic parameters in isolated porcine cerebral arteries. The perfused circle of Willis has a ...
Garry F - - 1989
Examination of the diseased llama often relies on clinical laboratory information to supplement that from the physical examination and history. Because of the llama's only recent importance as a companion animal, little information is available on the analysis and interpretation of clinical laboratory parameters in this species. Llamas possess red ...
Kutlar F F Department of Cell and Molecular Biology, Medical College of Georgia, Augusta - - 1989
We introduce a new high-performance liquid chromatographic procedure that uses a specific anion-exchange column for the separation of hemoglobin (Hb) Bart's (gamma 4), Hb H (beta 4), Hb Portland-I (zeta 2 gamma 2), Hb Portland-II (zeta 2 beta 2), and the abnormal Hb Constant Spring (alpha 2 extended beta 2) ...
Jopski B - - 1989
Hemoglobin (Hb) was encapsulated in phosphatidylcholine vesicles by removal of the detergent n-octyl beta-D-glucoside (OG) or n-octyltetraoxyethylene (C8E4) out of mixed detergent-lipid micelles in Hb solution. Three types of apparatus were used for dialysis. Dialysis buffer flow rates, the surface area of the dialysis membranes, and detergent-lipid interactions determined the ...
Westgren M - - 1989
The feto-placental blood volume was studied using a hemoglobin hemodilution technique in 15 erythroblastotic fetuses at 43 intravascular transfusions. Four severely anemic fetuses (Hb 30 g/l) had significantly larger blood volumes than 11 moderately anemic fetuses (Hb 30-79 g/l), 169 +/- 37 versus 105 +/- 32 ml/kg fetal body weight ...
Vidal-Naquet A - - 1989
Encapsulation methods using high pressure extrusion and homogenization were developed which produce hemoglobin-containing liposomes, approximately one micron or less in diameter with an oxygen-carrying capacity of more than half that of red blood cells (RBCs). These methods were developed for scaling-up liposome-encapsulated hemoglobin (LEH) production. Previously, the lack of adequate ...
Inoue H - - 1989
A new method for the identification of fetal hemoglobin (Hb F) in blood stains by reverse-phase high performance liquid chromatography is described. Differentiation between fetal and adult blood stains is based on the existence of gamma-chain peaks which are characteristics of Hb F. Very few gamma chains appeared on chromatograms ...
Djordjevich L - - 1989
Synthetic erythrocytes (SEs) are made by incorporation of stroma-free hemoglobin (SFH) or lipid-heme into liposomes. They form spontaneously at the interface between the phospholipid material and aqueous solution. SEs are spheroid vesicles with diameters between 0.01 and 4 microns, capable of carrying and delivering oxygen in a manner similar to ...
Tamura T - - 1989
A new compact high-performance instrument for monitoring the oxygenation state of the human newborn are developed. First we applied this instrument to the rat head, and next to the human arm. We could confirm that the volume of Oxy-Hb, Deoxy-Hb and total blood volume were well monitored by using our ...
Hinghofer-Szalkay H - - 1989
Using the "mechanical oscillator technique," the mass density of antecubital venous blood and plasma samples was measured 5-20 times in order to study the influence of postural changes (gravity dependence) on human blood mass density with 0.01 g.L-1 precision, while performing tilt table tests in 17 men. Hemoglobin concentration was ...
Ohba Y - - 1989
An abnormal hemoglobin found in an erythremic blood donor was separable only by isoelectrofocusing, where it was located at the cathodic edge of Hb A. Cation exchange high performance liquid chromatography of a tryptic digest from the total alpha chain revealed splitting of the alpha T-6 peak, although our routine ...
Kiefer C R - - 1988
In an effort to develop a rapid screening immunoassay for the presence of hemoglobin S (Hb S) in cord blood, we have produced a hybridoma (beta s-1) secreting a monoclonal antibody (MAb) with strict specificity for Hb S over hemoglobin (Hb A). A reactivity was observed for hemoglobin C (Hb ...
Claireaux G - - 1988
The effects of deep and acute hypoxia (PwO2 = 25 Torr) on oxygen transport characteristics (Hill number (n) and P50) were investigated in trout at 15 degrees C. When a fish is submitted to such an acute and deep hypoxia, a metabolic acidosis develops as soon as the arterial oxygen ...
Christensen S M - - 1988
A procedure is presented for the preparation of a purified fraction of adult human hemoglobin (HbAo) from one unit of outdated blood. The entire process requires less than 16 h and gives a sterile, endotoxin-free solution of HbAo (approximately 30 g) in a yield of 50%. The solutions are isoionic ...
Feola M - - 1988
The toxicity of hemoglobin solutions was studied in the context of their ability to activate serum complement (C). Three bovine polymerized hemoglobin solutions (BPHSs) with different degrees of purity were used for experiments in vitro and in vivo. BPHS-1 contained bacterial endotoxins (E) (5 EU/ml) and stromal phospholipids (PLs) (1.2 ...
Holland R A - - 1988
Blood O2 transport and Hb type have been studied in pouch young and adult of a marsupial, the Tammar Wallaby. The O2-Hb equilibrium curves (at 35.5 degrees C and PCO2 = 34 Torr) had a high P50 in the first few days of life, up to 49 Torr. This fell ...
Ueda H - - 1988
The changes in cerebral metabolism in mice in severe hypoxia were investigated by analyses of changes in the levels of energy metabolites and near-infrared spectrophotometric assessment of the states of hemoglobin and cytochrome oxidase. Under 4.4% O2, the contribution of anaerobic ATP production was at most about 20% of the ...
Braumann K M - - 1988
Parameters characterizing the hemoglobin oxygen affinity were determined in blood of 12 male patients suffering from arterial occlusive disease (AOD) of the legs and compared with data obtained earlier from healthy human subjects (controls). Due to a COHb content of 4.8% +/- 2.2% in the cigarette-smoking AOD patients, the standard ...
Vreman H J - - 1988
We measured the concentration of carboxyhemoglobin (HbCO) in blood samples from 32 neonates by spectrophotometry (IL282 CO-Oximeter) and gas chromatography, finding a strong positive correlation (r = 0.89) between the concentration of fetal hemoglobin (Hb F) and HbCO as measured by spectrophotometry, but not by gas chromatography. Thus, Hb F ...
Sato K - - 1988
Changes in methemoglobin (Met-Hb) concentrations during storage of whole blood and a hemolysate at refrigerated or various freezing temperatures were examined using experimentally prepared blood samples. When whole blood was stored at 3 degrees C, rapid reduction of Met-Hb was observed in the nitrite-treated blood whereas neither reduction nor formation ...
Robertson R J - - 1988
The effect of simulated altitude erythrocythemia on hemoglobin flow rate and maximal O2 uptake (VO2max) was determined for nine women sea-level residents. Test conditions included normoxia and normobaric hypoxia (16% O2-84% N2). Cycle tests were performed under normoxia (T1-N) and hypoxia (T1-H) at prereinfusion control and under hypoxia 48 h ...
Pesce M A - - 1988
Blood is drawn into capillary tubes containing saponin and the tubes placed into the reagent packs. Hemoglobin is denatured by mixing the hemosylate with a reagent containing lithium hydroxide and a non-ionic detergent. The absorbance is measured bichromatically at wavelengths of 577 and 633 nm. The calibration curve is stable ...
Card R T - - 1988
Blood may provide superior cardioplegia compared with crystalloid cardioplegic solution. However, the results are controversial. This may be due to a leftward shift of the hemoglobin (Hb)-O2 dissociation curve induced by hypothermia, increasing the oxygen affinity for Hb. This effect may negate the potential benefit of blood cardioplegia. The oxygen ...
Garver F A - - 1988
Variant hemoglobins S, C, and FHull were identified in newborn cord blood hemolysates with an immunoblot procedure. The abnormal hemoglobins were originally detected in cord blood hemolysates by cellulose acetate electrophoresis and presumptively identified according to their mobilities. Hemolysates that contained a hemoglobin variant again underwent electrophoresis and were transferred ...
Yamaguchi K - - 1988
In an attempt to estimate the influences of CO on the CO2 Bohr effect and the 2,3-diphosphoglycerate (DPG) effect linked to the reversible binding of O2 to the hemoglobin molecule (Hb), O2 dissociation curves of human blood in the presence of CO were investigated at 37 degrees C over a ...
Ardern J C - - 1988
A number of factors were identified which influence the determination of red blood cell glucose 6-phosphate dehydrogenase (G6PD). White blood cells were effectively removed from whole blood by filtration, resulting in a mean reduction of G6PD activity of greater than 1.0 U/g Hb. Optimal enzyme activity was found using haemolysates ...
Pristoupil T I - - 1988
The following trends aim to a more efficient exploitation of packed red blood cells (PRBC): 1. Improvement of the operative distribution of PRBCs for transfusions before expiration. 2. Prolongation of the expiration time by monitoring the biochemical and physical processes during banking. Maintenance of native hemoglobin and restoration or substitution ...
Hsia J C - - 1988
Preparation and use of hemoglobin-based blood substitutes, from stroma-free hemoglobin (SFH or Hb) and its DPG analogue-modified derivatives (PLP-Hb, ATP-Hb etc.) without thorough characterization and quality control in animal or human testing have produced, and may continue to produce, artifacts in the finished product. Thus the development of such a ...
Harvey J W - - 1988
1. Erythrocytes in whole blood samples from dogs with phosphofructokinase (PFK) deficiency had lower 2,3-diphosphoglycerate (2,3-DPG) concentrations, higher ATP concentrations, and were more alkaline fragile than normal canine erythrocytes. 2. Reticulocytes from a PFK-deficient dog contained nearly three times the ATP concentration of normal canine erythrocytes, and had 2,3-DPG concentrations ...
Glaister D H - - 1988
G-induced loss of consciousness (G-LOC) has emerged as an important operational problem of high-performance aircraft. Since it appears that G-LOC will continue to be a problem, a requirement exists to detect its occurrence in pilots so that the aircraft may be placed on autopilot. One excellent method of detecting G-LOC ...
Iwashita Y - - 1988
A new oxygen carrier for use as a blood substitute was prepared and characterized in vitro. Pyridoxylated hemoglobin, which was obtained by the reaction of human hemoglobin with pyridoxal-5-phosphate, was modified by alpha-carboxymethyl, omega-carboxymethoxyl polyoxyethylene (POE) of the molecular weight 3600 daltons. In order to eliminate viruses and nucleic acids ...
Sehgal L R - - 1988
Polymerization of SFH-P currently provides the only approach that leads to a hemoglobin solution that approximates the O2 carrying capacity of whole blood and can be infused without altering the COP of plasma. It appears to have an adequate O2 loading and unloading characteristic and a greatly improved intravascular half-life. ...
Farmer M C - - 1988
Liposome-encapsulated hemoglobin (LEH) is being developed at the Naval Research Laboratory as a universally transfusable oxygen-carrying blood replacement. A chemical engineering scale-up feasibility study has been completed recently. We report here the development of an encapsulation method which produces liters of phospholipid/cholesterol liposomes containing at least 16 g% hemoglobin in ...
Agishi T - - 1988
In order to investigate a new possibility for artificial blood with oxygen-carrying capability to be applied to other than mere supplementation, normothermic whole body rinse-out in which artificial blood deriving from perfluorochemical emulsion, Fluosol-DA 20% (Green Cross Co., Ltd., Osaka, Japan) or stabilized hemoglobin solution, (pyridoxylated hemoglobin)-(polyoxyethylene) conjugate solution (Ajinomoto ...
Sekiguchi S - - 1988
One of our major aims was to find ways to utilize outdated or virus-contaminated blood. Pyridoxylated hemoglobin (PLP-Hb), a possible substitute for red cells as an artificial oxygen carrier was prepared from outdated human blood. By conjugation with polyethylene glycol (PEG), the biological half life was increased about 3 folds ...
Soothill P W - - 1988
In order to determine whether the differences between fetal and adult hemoglobins are important to fetal oxygenation, pH, PO2, PCO2, bicarbonate, and base excess were measured in umbilical venous and arterial blood samples obtained from fetuses with erythroblastosis fetalis. The values from fetuses that had previously been transfused and had ...
Matsushita M - - 1988
A pyridoxylated-hemoglobin-polyoxyethylene conjugate (PHP) was developed from outdated human red cell hemoglobin through chemical modifications. The PHP has a mean molecular weight of approximately 90,000 daltons, with an acceptable P50 of 22 +/- 0.7 mmHg. This report describes exchange transfusion studies (ET) to a final hematocrit of 5 +/- 2% ...
Stratton L P - - 1988
Preventing the oxidation of hemoglobin in solution is one of the major requirements for the successful production and long-term storage of hemoglobin-based blood substitutes. To this end we have studied the effects of antioxidants on the rate of methemoglobin formation and disappearance in solutions of human and bovine hemoglobin at ...
Zaharopoulos P - - 1987
Hemoglobin crystals phagocytized by polymorphonuclear leukocytes were seen in cytologic preparations of a cerebrospinal fluid and two pleural fluids. In the last two cases, the crystals were seen within erythrocytes and also free in the background. Intraerythrocytic crystallization of hemoglobin is the result of polymerization of the hemoglobin molecules; it ...
Snyder S R - - 1987
Under deoxygenated conditions, bis(3,5-dibromosalicyl) fumarate reacts with hemoglobin selectively to cross-link the alpha subunits between Lys-alpha 1 99 and Lys-alpha 2 99. We have characterized further the properties of this recently described hemoglobin and have demonstrated its utility as a blood substitute. The oxygen transport characteristics of the cross-linked derivative ...
Burggren W W - - 1987
Very few studies have attempted to relate blood characteristics to body mass within, rather than between, species. Thus, respiratory and hematological properties of the blood of larval tiger salamanders (Ambystoma tigrinum) have been measured in animals ranging in body mass from approximately 2 to 112 g. This amphibian species was ...
Kumar A - - 1987
The effects of 30 days oral administration of a sublethal daily dose (0.1 g/kg body weight) of copper sulfate on the blood constituents of albino rats were studied. Percent hemoglobin, number of red blood corpuscles, plasma corpuscular volume and mean corpuscular volume were decreased significantly. No marked alteration was observed ...
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