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1.
Exposure of vitamin A acetate in freely dissolved state to γ-radiationin vitro caused a dose dependent degradation accompanied by the formation of new products. The radiation degradation products were separated by chromatography using step gradient elution. The parent molecule, vitamin A acetate, induced negligible haemolysis of erythrocytes. In contrast, the polar products formed by irradiation were found to be potent haemolysing agents. A highly polar product, eluted with methanol revealed maximum haemolytic activity. Acetylation of these products resulted in loss of their haemolytic properties. Similarly, vitamin E acetate, a known stabilizer of the biomembranes, after irradiation yielded products which caused haemolysis of erythrocytes. It was demonstrated that irradiation introduces hydroxyl groups which impart haemolytic properties to the radiation degradation products of vitamin A  相似文献   

2.
Haemolytic anaemia of obscure aetiology is a common complication of pregnancy in Nigeria. Treatment with antimalarials and folic acid is usually followed by a rapid remission, but response is slow in about 25% of patients and haemolysis continues uncontrolled in about 5%. The administration of prednisolone to six patients with uncontrolled haemolysis was followed by rapid recovery in five and possible benefit in one. Risks of prednisolone therapy to the mother appear to be slight and outweighed by the risks of continued severe anaemia and frequent blood transfusions. There seemed to be no appreciable increase of fetal loss compared with that in anaemic pregnancies not treated with prednisolone.  相似文献   

3.
Liver function and histology, together with the haematological changes, were investigated in 12 patients with Felty''s syndrome. Six of them were anaemic. The red cell mass was either normal or increased, and the anaemia was due to a considerable increase in the plasma volume. Two patients had increased haemolysis associated with red cell sequestration by the enlarged spleens.In eight patients liver function tests were abnormal, while in five the liver histology showed lymphocytic infiltration of the sinusoids and portal tracts together with portal tract fibrosis. One of these was later found to have a macronodular cirrhosis. In another there were apparent nodules without a true cirrhosis, and this appearance was also seen in two other patients with Felty''s syndrome in whom histology was available. An increased blood flow through the spleen was found in the two patients examined.  相似文献   

4.
On the basis of general haematological, clinicochemical, cytomorphological, cytochemical and nuclearmedical investigations the anaemia of chronic haemodialysis can be considered as a renal anaemia modified by a permanent dialysis. It is less characterized by lack of erythropoietin, but more by a strong lack of iron, moderate haemolysis and slight deficiency of folic acid. After gradual diagnostics the substitution treatment with iron is absolutely necessary, medication of folic acid should be attempted. A permanent therapy with 80-120 mg of iron weekly administered parenterally can be successfully performed and 10-15 mg of folic acid daily, which will markedly lower the rate of transfusion.  相似文献   

5.
Peroxidation of the membrane lipid structure of red blood cell leads to haemolysis and anaemia in haemodialysis patients. Dietary constituents of antioxidant vitamins and trace elements may play an important role in protecting against oxidant damage. In this study, the effects of supplementation of vitamin C and zinc on osmotic fragility and lipid peroxidation of erythrocytes were investigated in 34 zinc-deficient haemodialysis patients. Sixteen sex- and age-matched normal volunteers acted as controls. Patients were randomized to receive vitamin C (250 mg day(-1)), zinc (20 mg day(-1)) or a placebo treatment for 3 months. The levels of vitamin C, zinc, malondialdehyde (MDA) and osmotic fragility were measured initially and 3 months after supplementation. Mean serum concentration of vitamin C and zinc increased significantly in the groups at the end of the respective study periods. Supplementation with vitamin C and zinc improved osmotic fragility, and decreased the level of MDA in the groups, but some side-effects (i.e. nausea, vomiting, fever, muscle pain, weakness) were observed during the zinc treatment. The results showed that the supplementation of both treatments decreased osmotic fragilty and MDA in zinc-deficient haemodialysis patients. However, vitamin C treatment was found to be safer than zinc supplementation.  相似文献   

6.
The effects on cellular structures of products of peroxidation of rat liver microsomal lipids were investigated. A system containing actively peroxidizing liver microsomal fraction was separated from a revealing or target system by a dialysis membrane. The target system, contained in the dialysis tube, consisted of either intact cells (erythrocytes) or subcellular fractions (liver microsomal fraction). When liver microsomal fractions were incubated with NADPH (or an NADPH-generating system), lipid peroxidation, as measured by the amount of malonaldehyde formed, occurred very rapidly. The malon-aldehyde concentration tended to equilibrate across the dialysis membrane. When the target system consisted of erythrocytes, haemolysis occurred abruptly after a lag phase. The lysis was greatly accelerated when erythrocytes from vitamin E-deficient rats were used, but no haemolysis was observed when erythrocytes from vitamin E-treated rats were used. When, in the same system, freshly prepared liver microsomal fractions were exposed to diffusible factors produced by lipid peroxidation, the glucose 6-phosphatase activity markedly decreased. A similar decrease in glucose 6-phosphatase activity, as well as a smaller but significant decrease in cytochrome P-450, was observed when the target microsomal fractions were exposed to diffusible factors derived from the peroxidation of liver microsomal lipids in a separate preincubation step. These and additional experiments indicated that the toxicological activity is relatively stable. Experiments in which the hepatic microsomal fractions destined for lipid peroxidation contained radioactively labelled arachidonic acid, previously incorporated into the membranes, showed that part of the radioactivity released from the microsomal fraction into the incubation medium entered the dialysis tube and was recovered bound to the constituents of the microsomal fractions of the target system. These results indicate that during the course of the peroxidation of liver microsomal lipids toxic products are formed that are able to induce pathological effects at distant loci.  相似文献   

7.
174 serum ferritin assays in 121 patients with various haemolytic disorders have been performed. The mean serum ferritin levels were significantly increased in all these disorders in contrast to healthy controls. The highest serum ferritin levels were found in pyruvate kinase (PK) deficiency, moderate increase was observed in hereditary sphaerocytosis (HS) and in autoimmune haemolytic anaemia (AIHA) with massive haemolysis and in glucose-6-phosphate dehydrogenase (G-6-PD) deficiency. Mild elevation of serum ferritin levels was depicted in paroxysmal nocturnal haemoglobinuria (PNH), in beta thalassaemia minor and in other types of haemoglobinopathies. The range of values was associated with a degree of haemolysis and its relation to duration of the disease was not apparent in most cases. Highly significant differences between serum ferritin levels in splenectomized and non-splenectomized patients with HS and between serum ferritin levels in patients with AIHA with massive haemolysis or in remission were found. As compared to normal controls, significant increase of serum ferritin levels was observed even in patients with AIHA in remission or in splenectomized patients with HS. In two patients with PK deficiency the levels exceeding 2,000 micrograms/l indicated manifest iron overload. A reliability of serum ferritin assay as an index of iron stores in haemolytic disorders has been discussed.  相似文献   

8.
The study was aimed at analysing the epidemiological structure of patients with liver cirrhosis without HBsAg treated in 1980-1988. There were 231 of such cases in this period of time. The most frequent cause of liver cirrhosis in patients under 60 years of life was chronic alcoholism whereas 40% of the diagnosed liver cirrhosis in older persons was of unclear etiology. Patients complaints, clinical examinations, and results of the laboratory tests were analysed. The course of the disease was more severe in alcohol-produced liver cirrhosis leading to the haemorrhage from esophageal varices in 36%, and coma in 8% of cases. Alcohol-produced liver cirrhosis promoted other complications such as: cancer of the liver, hepato-renal syndrome or encephalopathy. Liver cirrhosis of unclear etiology in the elderly may be a consequence of the prolonged exposition to environmental pollutants. More severe course of alcohol-produced liver cirrhosis may depend on simultaneous action of two harmful factors: alcohol and environmental pollutants.  相似文献   

9.
Erythrocyte and serum ferritin was determined in 36 patients with different pictures of diseases and under bleeding therapy in idiopathic haemochromatosis (IH). With latent iron deficiency there was no significant difference in the ferritin content of erythrocytes in comparison with the control group. The intraerythrocyte ferritin content in idiopathic haemochromatosis is always increased and will normalize under bleeding therapy as well serum ferritin. After disrupting the therapy the ferritin content in erythrocytes will more rapidly increase again than in the serum. Increased erythrocyte ferritin could be identified in patients with anaemia due to ineffective erythropoiesis.  相似文献   

10.
We applied our 'clinical glycomics' technology, based on DNA sequencer/fragment analyzers, to generate profiles of serum protein N-glycans of liver disease patients. This technology yielded a biomarker that distinguished compensated cirrhotic from noncirrhotic chronic liver disease patients, with 79% sensitivity and 86% specificity (100% sensitivity and specificity for decompensated cirrhosis). In combination with the clinical chemistry-based Fibrotest biomarker, compensated cirrhosis was detected with 100% specificity and 75% sensitivity. The current 'gold standard' for liver cirrhosis detection is an invasive, costly, often painful liver biopsy. Consequently, the highly specific set of biomarkers presented could obviate biopsy in many cirrhosis patients. This biomarker combination could eventually be used in follow-up examinations of chronic liver disease patients, to yield a warning that cirrhosis has developed and that the risk of complications (such as hepatocellular carcinoma) has increased considerably. Our clinical glycomics technique can easily be implemented in existing molecular diagnostics laboratories.  相似文献   

11.
N Omran  E Neumann 《Blut》1979,39(5):359-363
A simple, rapid and inexpensive cytochemical method for the detection of vitamin B 12 deficiency was applied in several types of anemias and matched with the levels of vitamin B12 and folic acid in the serum of the patients. It was found that in patients with low vitamin B12 levels the stained erythrocytes and the erythroid precursors showed a yellowish brown discoloration, which was not detected in folic acid deficiency and all other types of anemias. This test therefore may be used for differentiation between B12 and folate deficiency whenever megaloblastic anemia is diagnosed.  相似文献   

12.
Normochromic or normocytic anaemia is a common side effect of treatment with cisplatin. Two patients treated with cisplatin 100 mg/m2 in combination with vinblastine, bleomycin, and actinomycin D developed haemolytic anaemia. Neither patient had evidence of haemolysis before treatment, and in both cases severe haemolytic anaemia developed after several courses of cisplatin and when the cancer had regressed almost completely. The importance of haemolysis in the development of anaemia after cisplatin treatment has not been investigated fully and further studies are needed.  相似文献   

13.
In this report,Eperythrozoon leading haemolysis was identified in human blood. A patient with long-term anaemia was selected for blood smear examination and electron microscopy. The microscopic results showed a lot of small organisms attaching on the surface of erythrocytes. The partial 16S rRNA gene was amplified and confirmed as haemoplasma by sequence alignment. Phylogenetic analysis showed it fell in the same cluster with otherEperythrozoon species in haemoplasma group. It was the first time to confirm the haemoplasma infection in human blood by molecular assay combined with microscope. Such infection may be a potential criminal of some cases of human unknown origin anaemia.  相似文献   

14.
To examine the possibility that intravascular haemolysis may lead to intravascular coagulation we have compared the degree of fibrin deposition, as measured by levels of serum fibrinogen-fibrin degradation products (F.D.P.), in two different types of intravascular haemolysis associated with red cell fragmentation. F.D.P. levels in 56 patients with intravascular haemolysis secondary to prosthetic heart valves were compared with those in 18 patients who had microangiopathic haemolytic anaemia (M.H.A.) associated with malignant hypertension or renal disease. F.D.P. levels were raised in almost all the patients with M.H.A., and this group had significantly higher levels than any of the valve replacement groups. In contrast, in the prosthetic valve patients F.D.P. levels were usually normal and bore no relation to the degree of haemolysis. It is suggested that in the absence of other precipitating factors intravascular haemolysis will not initiate intravascular coagulation. In M.H.A., while the intravascular haemolysis appears to be a consequence of an underlying intravascular coagulation, it is likely that persistence of the coagulation disturbance is related more to factors such as small vessel damage than to the release of any thromboplastic substances from fragmented red cells.  相似文献   

15.
Sheep were treated with large amounts of copper (20 mg of CuSO4,5H2O/kg body wt. per day) for 9 weeks to examine the effect of copper excess on iron metabolism. In addition to confirming that massive haemolysis and accumulation of copper occurs in the liver, kidney and plasma after 7 weeks of exposure to excess copper, it was observed that excess copper produced an increased plasma iron concentration and transferrin saturation within 1 week. Further, iron preferentially accumulated in the spleen between 4 and 6 weeks of copper treatment, producing 3-fold increases in the iron content of both the ferritin and non-ferritin fractions. A 3-4 fold increase was also observed in the amount of ferritin that could be isolated from the spleen. The copper treatment had little or no effect on the concentration of iron in the liver and bone marrow. The following properties of erythrocytes were also unaffected by copper treatment: size, haemoglobin content and pyruvate kinase activity, although the erythrocyte concentration of copper increased after 6 weeks. Copper accumulated in the spleen between 6 and 9 weeks, probably owing to the phagocytosis of erythrocytes containing high concentrations of copper. The data suggest that copper excess influences iron metabolism, initially by causing a compensated haemolytic anaemia, and later by interfering with re-utilization of iron from ferritin in the reticuloendothelial cells of the spleen.  相似文献   

16.
N E Zorn  J T Smith 《Life sciences》1990,47(2):167-173
Ingestion of megadoses of certain vitamins appears to influence the in vivo methylation of mercuric chloride in guinea pigs. The addition of megadoses of vitamin B12 fed either singularly or in combination with folic acid resulted in increased methylmercury concentrations in the liver. Moreover, percent methylmercury levels were significantly increased with B12 treatment in the liver (B12 only and B12/folic acid) and brain (B12/vitamin C). Incorporation of high levels of folic acid into the dietary regime also increased the methylmercury concentration particularly in the liver and hair tissues. The addition of vitamin C in the diet, particularly in combination with B12 (brain) or folic acid (muscle) resulted in increased methylmercury levels in these tissues and percent methylmercury values with B12 in the muscle and brain tissue.  相似文献   

17.
Common manifestations of Wilson's disease are disorders of the liver and brain. A rare complication of this inherited disease is acute intravascular haemolytic anaemia. We report the case of a 33-year old female patient who was admitted to the hospital with acute haemolysis as the initial symptom of Wilson's disease. The haemolysis preceded the definitive diagnosis by 20 months. It is concluded that in any case of unclear haemolytic anaemia, especially in adolescents or in young adults, Wilson's disease should be considered.  相似文献   

18.
On the basis of findings in examinations made in 50 patients (25 with hypoplastic anaemia and 15 in the hypoplastic stage of acute leukemia) a simple mathematical method was developed for the differential diagnosis of these two diseases. The following laboratory findings were used for calculating a formula: cellularity of the bone-marrow, percentage of blast cells in the myelogram, percentage of blast cells in leukocyte concentrate, morphology of erythrocytes, presence of normoblastosis, percentage of monocytes and absolute number of neutrophils in the peripheral blood. This method allows the correct diagnosis to be made in 91% of cases with hypoplastic anaemia and in 100% of cases with acute leukemia. By using 7 laboratory findings to be obtained easily this method will enable a correct diagnosis to be made even in those situations where hitherto it was very difficult to make a differential diagnosis or where it was impossible at all.  相似文献   

19.
HPLC-EC has been used to measure the appearance of 5-CH3-H4 folic acid in human plasma following oral administration of folic acid. The process was found to be saturable in accordance with Michaelis-Menten kinetics. The apparent Km for this enzyme system indicates that low doses of oral folic acid are rapidly converted into 5-CH3-H4 folic acid, an observation consistent with the needs of intestinal absorption of essential trace nutrients. The appearance of L. casei active folate in plasma was not rate-limited and showed a biphasic relationship to dose. Preparative HPLC combined with L. casei bioassay demonstrated that most of the L. casei active folate appearing in plasma following a 20,000-micrograms dose of folic acid was due to the unmodified vitamin, only 5.6% being due to 5-CH3-H4 folic acid and with no detectable contribution from 5-CHO-H4 folic acid. The absorption characteristics of the system seem consistent between and within subject(s). No relationship could be demonstrated between predose levels of plasma 5-CH3-H4 folic acid and total folate in erythrocytes, which reflect the status of transport and storage forms of the vitamin, respectively.  相似文献   

20.
This study was carried out to investigate sequel of oxidative insult to human erythrocytes induced by a water-soluble radical initiator, 2,2'-azobis-(amidinopropane) dihydrochloride (AAPH) and the effect of a commercially available mixed antioxidant (Blackmores, BioAce Excel), containing alpha-tocopherol, ascorbic acid, beta-carotene and some herbal extracts (containing grape seed catechins and milk thistle derived silybin), on lipid peroxidation, degradation of membrane proteins and haemolysis. We performed this study in order firstly to clarify aspects of the mechanism of AAPH induced free radical damage in human erythrocytes and secondly to establish in vitro conditions by which the efficacy of mixed antioxidant preparations may fairly and objectively be compared. In the process of oxidation initiated by peroxyl radical, a rapid loss of reduced glutathione occurred in the first 60 min. Formation of thiobarbitric acid-reactive substances indicative of lipid peroxidation increased subsequently and almost reached maximal levels at 180 min before significant apparent degradation of membrane proteins was detected. At this point, a significant haemolysis occurred. This sequence of events is consistent with the idea that haemolysis is a consequence of lipid peroxidation and the degradation of membrane proteins. The mixed commercial antioxidant, which suppressed lipid peroxidation and protected membrane proteins against degradation induced by peroxyl radicals, also effectively delayed AAPH induced haemolysis. The system we describe provides a sound objective basis for the in vitro comparison of the potential efficacy of the hundreds of antioxidant nutritional supplements currently available in the market place.  相似文献   

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