A novel device for the non-invasive measurement of free hemoglobin in blood bags.

The production of red blood cell concentrates from human donors is a very expensive procedure and human resources are in short supply. Under perfect storage conditions at a temperature of 2-6 degrees C, a blood bag must be used within 35-49 days (in Germany). Visual inspection of the bag for apparent hemolysis by a blood bank physician is a crucial but subjective quality control assessment. Since an interruption of the cold chain cannot be definitely ruled out, bags are often disposed of prematurely for safety reasons. There is currently no method of testing a closed blood bag with respect to hemolysis for its suitability to be used in a transfusion. The proposed optical measuring device is a hemoglobin sensor which determines the free hemoglobin in standard erythrocyte concentrates without opening the bag. The optical measurements are done on the flexible tube connected to the main bag. The optical measurements were evaluated using standard hemoglobin solutions with an accuracy of 0.005 g/dL. These investigations show that in the future each blood bag can be tested non-invasively for its content of free hemoglobin. This will contribute to decreasing the wastage rate of red blood cell concentrates.     

DIAGNOSIS OF THE HEMOLYTIC ANEMIAS

Classification of the varieties of hemolytic anemia is based upon whether hemolysis is due to inherent defects within the erythrocyte or to extracellular factors.Confirmation of diagnosis in cases in which the disease is clinically suspected is made upon the basis of the following laboratory data: Hyperbilirubinemia giving an indirect van den Bergh reaction, observation of typical factors in a smear of the blood, a reactive bone marrow, increased urobilinogen in stools and urine, and absence of bilirubinuria.Differentiation of the different types depends upon determination of altered fragility of erythrocytes as indicated by tests of resistance to heat, acid, and mechanical and osmotic stimuli, and upon the identification of an antibody.The importance of detecting antibodies demonstrable in acid serum is mentioned.In a majority of cases, acquired hemolytic anemia is caused by antibodies, malignant disease, or toxic agents.     

炎症性贫血的病因、诊断与治疗研究进展

感染、自身免疫紊乱、慢性疾病和年龄等很多原因都会导致炎症发生并发展为贫血。炎症性贫血(anemia of inflammation AI)通常为正细胞正色素性贫血,临床表现温和。系统性的铁利用、红细胞生成、红细胞生存期特征的变化导致了炎症性贫血。最佳治疗是纠正病因,然而当病因不清或难以诊断时,治疗炎症性贫血的办法就非常有限了。铁调素(Hepcidin)是近年研究铁利用调节的中心。由于铁调素定量分析技术的发展,人们逐渐认识到其在各种疾病中的作用。最近研究集中在铁调素表达调节通路,并发现了药物治疗的靶点。由于治疗上的巨大进步,分析正常血红蛋白对疾病预后的影响,就可以明确炎性疾病发生和死亡过程中贫血是否具有可逆性。     

Erythrocyte aging in sickle cell disease.

Physiological removal of old erythrocytes from the circulation by macrophages is initiated by binding of autologous IgG to senescent cell antigen (SCA). SCA is generated from the anion exchanger band 3. This process is accompanied by a number of alterations in the function and structure of band 3. We measured these aging-related parameters in erythrocytes from individuals with sickle cell anemia. Most sickle erythrocytes have characteristics that are also found in senescent normal erythrocytes, such as an increased density and considerable concentrations of cell-bound IgG. Together with the concomitant changes in structure and function of band 3, these data suggest that most sickle erythrocytes have undergone a process of accelerated aging. Preliminary results indicate that this process is reversed upon vitamin E supplementation. These data show that the erythrocyte aging paradigm may provide a useful conceptual framework for the study of the pathophysiology and the evalution of therapeutic intervention in sickle cell disease, and support the view that oxidation can generate neoantigens that are recognized by autoantibodies.     

A theoretical model to predict the behavior of glycosylated hemoglobin levels

The measurement of glycosylated hemoglobin as a percentage of total hemoglobin is rapidly becoming the standard method of monitoring the average blood sugar level in diabetics for research purposes and may soon become the standard for clinical care and diagnosis. Much speculation exists in the literature about the nature of the glycosylation reaction. Most experimenters expect a linear relationship between the plasma glucose level and percent glycosylated hemoglobin in whole blood; however, a curve of decreasing slope with increasing glucose concentration is found.Here, a reaction model including simple first order kinetics between glucose and hemoglobin and a finite erythrocyte life of 120 days is considered. By carrying out the integration for each erythrocyte cohort followed by an integration combining all cohorts, a curve corresponding to the experimental result is found. In addition, results on expected glycosylated hemoglobin percent as a function of erythrocyte age and plasma glucose concentration are presented as well as a plot of glucose concentration versus glycosylated hemoglobin percent for the 40-day erythrocyte life in mice. All of the results correlate with experimental values in the literature if a rate constant of k = 1·0 × 10^?5dlmg^?1 day is used.The evaluation of a radioactive iron-transferrin experiment in the literature reveals the possibility that the glycosylation reaction begins during erythropoiesis.Finally, a curve is displayed which shows the expected 120-day decay during normoglycemia, of an elevated glycosylated hemoglobin level resulting from a preceding period of constant hyperglycemia.     

In vitro kinetics of oxygen transport in erythrocyte suspension or unmodified hemoglobin solution from human and other animals

Oxygen transport behavior in erythrocyte suspension or in hemoglobin solution was studied as a potential therapeutic model for the clinical treatment of blood loss, and this can also provide physiological data with which to evaluate blood substitutes. In the present project, we examined the in vitro kinetics of hemoglobin binding to and releasing oxygen, to provide detailed oxygen-flux measurements for unmodified hemoglobin solutions and erythrocyte suspensions in human, as well as other vertebrates. An in vitro method was used, based on a widely used artificial system, with the oxygen saturation level being detected in real time. Results from this study indicated that the kinetic curves of human erythrocyte suspensions and hemoglobin solutions were either S-shaped or hyperbolic, respectively. Based on these curves, the significance of T(50) emerged in our investigation, where T(50) is defined as the time needed for 50% hemoglobin to be saturated with oxygen, and reflects the efficiency with which hemoglobin carries oxygen. This parameter may be used to diagnose blood diseases, and could be a standard for evaluating blood substitutes. In this study, we also compared the T(50) of 4 species of vertebrates, and found that it shows a distinct efficiency of oxygen binding related to species, and potentially reveals the evolutionary function of hemoglobin and its possible adaptation to the environment.     

Functional consequences of sphingomyelinase-induced changes in erythrocyte membrane structure

Inflammation enhances the secretion of sphingomyelinases (SMases). SMases catalyze the hydrolysis of sphingomyelin into phosphocholine and ceramide. In erythrocytes, ceramide formation leads to exposure of the removal signal phosphatidylserine (PS), creating a potential link between SMase activity and anemia of inflammation. Therefore, we studied the effects of SMase on various pathophysiologically relevant parameters of erythrocyte homeostasis. Time-lapse confocal microscopy revealed a SMase-induced transition from the discoid to a spherical shape, followed by PS exposure, and finally loss of cytoplasmic content. Also, SMase treatment resulted in ceramide-associated alterations in membrane–cytoskeleton interactions and membrane organization, including microdomain formation. Furthermore, we observed increases in membrane fragility, vesiculation and invagination, and large protein clusters. These changes were associated with enhanced erythrocyte retention in a spleen-mimicking model. Erythrocyte storage under blood bank conditions and during physiological aging increased the sensitivity to SMase. A low SMase activity already induced morphological and structural changes, demonstrating the potential of SMase to disturb erythrocyte homeostasis. Our analyses provide a comprehensive picture in which ceramide-induced changes in membrane microdomain organization disrupt the membrane–cytoskeleton interaction and membrane integrity, leading to vesiculation, reduced deformability, and finally loss of erythrocyte content. Understanding these processes is highly relevant for understanding anemia during chronic inflammation, especially in critically ill patients receiving blood transfusions.     

Correlations of blood selenium with hematological parameters in West German Adults

The serum selenium and the whole blood selenium of 72 healthy persons (47 women, 25 men) was determined. There exist sex specific differences of the whole blood selenium between men (98±19 μg Se/L) and women (89±17 μg Se/L). The serum selenium did not show sex specific differences, but sex specific differences are found if the total amount of extracellular selenium is calculated by correction of the serum selenium with the hematocrit. Women have more extracellular selenium/L whole blood (40±8 μg Se) than men (36±7 μg Se). Men have more intraerythrocyte selenium (cellular selenium=67±14 μg Se) in one L whole blood than women (52±17 μg Se). There exist also sex specific differences if the cellular selenium is calculated/g hemoglobin (men .44 μg Se/g Hb, women .37 μg Se/Hb) or per erythrocyte (men 136.1×10^?19 g Se/Ery, women 113.9×10^?19 g Se/Ery). In the cellular compartment of one L whole blood on the average 1.56 times more selenium is present than in the extracellular compartment. Most of the intraerythrocyte selenium is hemoglobin bound (84%) and utmost 16% glutathione peroxidase associated. An erythrocyte contains about 3500 mol glutathione peroxidase, or, for every 80000 mol hemoglobin one mol glutathione peroxidase. A standard man needs about 2.5 μg selenium/d for the synthesis of the hemoglobin and the erythrocyte. The hematological parameters hemoglobin and the erythrocyte number are correlated with the cellular selenium and the ratio cellular selenium/extracellular selenium. Positive significant correlations are found that are best if a parabolic model is used to interpret the shape of the curves. From the shape of the best correlation lines it can be concluded that selenium may be beneficial for hemoglobin synthesis and erythropoesis. The extracellular selenium may have influence on the volume of the erythrocyte by protecting the outer erythrocyte membrane from lipid peroxidation. A method is reported based on the carbon furnace atomic absorption spectroscopy, which is able to determine without wet digestion selenium in whole blood.     

Sfxn1 is essential for erythrocyte maturation via facilitating hemoglobin production in zebrafish

Previous reports revealed that mutation of mitochondrial inner-membrane located protein SFXN1 led to pleiotropic hematological and skeletal defects in mice, associated with the presence of hypochromic erythroid cell, iron overload in mitochondrion of erythroblast and the development of sideroblastic anemia (SA). However, the potential role of sfxn1 during erythrocyte differentiation and the development of anemia, especially the pathological molecular mechanism still remains elusive. In this study, the correlation between sfxn1 and erythroid cell development is explored through zebrafish in vivo coupled with human hematopoietic cells assay ex vivo. Both knockdown and knockout of sfxn1 result in hypochromic anemia phenotype in zebrafish. Further analyses demonstrate that the development of anemia attributes to the biosynthetic deficiency of hemoglobin, which is caused by the biosynthetic disorder of heme that associates with one?carbon (1C) metabolism process of mitochondrial branch in erythrocyte. Sfxn1 is also involved in the differentiation and maturation of erythrocyte in inducible human umbilical cord blood stem cells. In addition, we found that functional disruption of sfxn1 causes hypochromic anemia that is distinct from SA. These findings reveal that sfxn1 is genetically conserved and essential for the maturation of erythrocyte via facilitating the production of hemoglobin, which may provide a possible guidance for the future clinical treatment of sfxn1 mutation associated hematological disorders.     

Primary Tumours of the Small Bowel and its Mesentery

Twenty-seven primary small bowel tumours encountered at the University of Alberta Hospital in a 10-year period have been reviewed. Seventeen symptomatic growths were treated by resection and 10 asymptomatic tumours were discovered incidentally. During this same period, three intramesenteric lipomas were found. Small bowel tumours were malignant in 15 of the 17 symptomatic cases and benign in seven of the nine asymptomatic cases. Carcinoid tumours, malignant lymphomas, non-lymphoid sarcomas and carcinomas were the common malignant neoplasms while adenomas, lipomas, myomas, fibromas and angiomas comprised the majority of benign growths reported. Symptoms of anorexia, anemia, abdominal pain, obstruction and hemorrhage suggest small bowel tumour if commoner pathology has been ruled out.     

Oxygen tension and water-soluble products of lipid peroxidation in blood of volunteers in hypobaric hyperoxia]

Oxygen tension in the arterial blood with transcutaneous method (tcPO2) and TBA-active products of venous blood plasma were measured during simulation of extravehicular activity. There was a parallel increase of tcPO2 and the level of TBA-active products upon introduction of hypobaric hyperoxia factor. Detrimental action of lipid peroxidation products on erythrocyte membranes can be one of the factors of anemia during space flight.     

Hemoglobin values in aged men

To determine whether the level of hemoglobin declines with age a group of 92 aged males averaging 81 years was carefully examined to exclude disease likely to cause anemia or polycythemia. Arterial blood was drawn from each patient before he was allowed out of bed in the morning to avoid the hemoconcentrating effect of the erect posture. The mean hemoglobin concentration was 12.9 ± 1.5 g.% and the values were distributed normally. There was a decline of hemoglobin concentration with age which is probably nonlinear since it becomes more marked in the very old. The decline is thought to be part of the aging process and not a manifestation of disease.     

Acetylsalicylic acid antagonizes the bleeding-induced changes in hemoglobin proportions in normal adult rats

Normal adult Sprague-Dawley rats were made anemic by repeated phlebotomy. Ion-exchange chromatography of anemic blood showed newborn like hemoglobin proportions, involving the same six hemoglobin components as is found when newborn and adult blood are compared. However, acetylsalicylic acid intake during anemia failed to demonstrate the changes in hemoglobin proportions, either totally or partially, depending upon the doses. Since acetylsalicylic acid inhibits prostaglandin synthesis, the data suggest that one or more prostaglandins may be involved in the process of reverse switching of hemoglobin in adult rat erythroid cells during erythropoietic stress.     

Covalent fixation of hemoglobin to dextran phosphates decreases its oxygen affinity.

The interactions between various dextran phosphates and Hb (hemoglobin) were studied by measuring the oxygen-binding parameters of the mixtures. The effector properties of polymers were found to depend on the concentration of monoalkylmonophosphate groups on the polymers and also on their molecular weights. The covalent fixation of dextran phosphates bearing aldehydic groups to oxyHb and deoxyHb was carried out. The oxygen-binding properties of the conjugates thus obtained depended upon the initial form of the protein. Thus, only the conjugates synthesized from deoxyHb exhibited a low oxygen affinity, which means that, in this case, the linkages between the dextran phosphate and the protein allow a permanent interaction of the phosphate groups with amines of the 2,3-diphosphoglycerate binding site. The Hill coefficient values of these conjugates were smaller than that of free Hb, corresponding to a loss of the cooperativity of the protein upon fixation of polymers. However, as these new conjugates are capable of unloading more O2 than blood when subjected to oxygen pressures corresponding to physiological conditions, they can be regarded as potential erythrocyte substitutes.     

Changes of gas exchange parameters and of functional-biochemical properties of erythrocytes in dynamics of experimental anemia in rats

In experiments on male Wistar rats, in a specially constructed computerized installation, O₂ consumption by the animals in comparison with changes of hematological, biochemical, and rheological blood properties is studied after anemization—acute blood loss (12–15% of the total blood mass). An increase of the O₂ consumption by the organism and tissues by 18–28% has been revealed for the first 7 days after the blood loss, in spite of a pronounced decrease of hematocrit and of the amount of erythrocytes and hemoglobin in peripheral blood by 20–25% of the initial level. There was a 5–10-fold increase of the content of immature erythrocyte forms—reticulocytes and a progressive rise of cell acidic resistance, which is characteristic of young erythrocyte forms. An increase of O₂ consumption at a decrease of the blood oxygen capacity (a low hemoglobin level) seems to be due to the more efficient transport and yield of O₂ to tissues. At the 3rd and 7th day after the blood loss, activity of Na,K-ATPase has been found to increase by 60% and 20%, respectively. Analysis of the erythrocyte rheological properties has shown that the maximal firmness of aggregates (U_q) and the aggregation rate (1/T) decrease progressively beginning from 3 days after the blood loss; index of deformability (I_max) turned out to be elevated by 7–11%, probably due to an increase of the cell membrane elasticity. The conclusion is made that changes of erythrocyte rheological properties are interconnected with changes of the Na,K-ATPase activity and are directed at optimization of blood circulation in large vessels and the capillary network.     

Screening laboratory tests for Crohn's disease.

The prevalence of abnormal values of initial screening laboratory tests was assessed for 24 children who eventually proved to have Crohn''s disease. The screening tests included in this analysis were fecal alpha 1-antitrypsin (FA) concentration, erythrocyte sedimentation rate (ESR), total leukocyte count, serum albumin level, hemoglobin concentration, and qualitative testing of stool for the presence of blood. Of the 24 patients, 21 had abnormal FA values, 17 had anemia, 19 had an increased ESR, 14 had hypoalbuminemia, rectal bleeding was found in 8, and none had leukocytosis. All 24 patients had at least one abnormal screening test value; the most frequently abnormal result was the FA concentration. Pediatric patients without elevated FA values, anemia, a high ESR, bloody stools, or hypoalbuminemia are unlikely to have active Crohn''s disease.     

Nature of the chalone fraction of erythrocyte extracts

The chalone fraction of erythrocyte extracts is immunologically identical to albumin and not identical to hemoglobin. It differs from albumin and hemoglobin in biological properties and electrophoretic mobility. The immune antichalone serum permits evaluating erythropoiesis in posttransfusion polycythemia and acute blood loss.     

Anemia in Ducks Infected with Leucocytozoon simondi*†

SYNOPSIS. Thirty-four white Pekin ducklings were used to study the anemia associated with infection by Leucocytozoon simondi. The first appearance of gametocytes in the peripheral blood, as detected by thin smears, marked the onset of anemia. This anemia lasted for the duration of the initial parasitemia, usually reaching a low point early in the infection (1 to 5 days post patency) and returning slowly to normal as the parasitemia decreased. Greatest gametocyte density occurred 5 to 8 days post patency. In a number of cases recovery from anemia began simultaneously or even prior to the highest level in the gametocyte density. In low level parasitemias a fluctuation occurred in erythrocyte numbers which corresponded with the peaks of gametocyte density. In none of the infections was a sufficient number of parasite observed to account for the existing anemia. Haemopoietic activity was observed for a brief period at the time of maximum erythrocyte loss in only a few birds. The overcompensation for erythrocyte loss at the end of the primary parasitermia favors the view that increased erythrocyte production may account for the short duration of haemopoiesis.     

自身免疫性溶血性贫血(AIHA)患者的不同输血方法与效果

目的:探讨不同输血方法治疗自身免疫性溶血性贫血(autoimmune hemolytic anemia,AIHA)的效果。方法:2017年1月-2018年12月选择在本院血液科诊治的64例自身免疫性溶血性贫血患儿,根据输血方法的不同分为观察组与对照组,各32例。观察组给予洗涤红细胞输注治疗,对照组给予非洗涤红细胞(悬浮红细胞)输注治疗,记录两组输血效果。结果:治疗后4 w观察组的总有效率显著高于对照组(100.0%vs.87.5%,P0.05)。两组治疗后4 w的红细胞计数与血红蛋白都显著高于治疗前,且观察组显著高于对照组(P0.05)。观察组的吸氧、机械通气、住院时间都显著少于对照组(P0.05)。观察组治疗过程的过敏反应、发热反应、紫癜等不良反应发生率显著低于对照组(3.1%vs. 21.9%,P0.05)。结论:洗涤红细胞输注治疗自身免疫性溶血性贫血患儿能促进机体红细胞计数与血红蛋白恢复正常,减少不良反应的发生,提高治疗效果与促进患儿康复。     

The effect of copper on erythrocyte deformability. A possible mechanism of hemolysis in acute copper intoxication

Although the development of hemolytic anemia as a complication of acute copper intoxication is well documented, the precise mechanism by which copper produces accelerated erythrocyte destruction is unknown. Normal erythrocyte survival depends in part on the ability of the cell to deform and pass through narrow areas of microcirculation in the liver and especially in the spleen. In the present study, it is demonstrated that toxic concentrations of copper rapidly and markedly reduce erythrocyte deformability. This reduction in cell deformability is associated with a marked increase in membrane permeability and osmotic fragility of copper-treated cells. Further, the decrease in deformability occurs despite normal levels of cell ATP and the apparent absence of oxidative damage to the cell. These observations indicate that copper-mediated changes in the erythrocyte membrane may be responsible for reducing the flexibility of the cell. The loss of deformability could act to reduce erythrocyte survival and thus explain the hemolysis associated with copper intoxication in vivo.