Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002871 (anemia)
 52,094 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Two examples of human IgM cold agglutinins agglutinated human RBC only after enzyme treatment in vitro. Proteases were optimally effective, neuraminidase was also effective. The cold agglutinins did not coat native RBC but were directed against "cryptic" RBC determinants. The cold agglutinins belonged to the anti -I/-i complex indicating a "new" type of I/i determinants. They were strongly accessible to cold agglutinin interaction on native RBC of a patient with congenital dyserythropoietic anaemia. Enzyme treatment of RBC was shown to be not only suited for defining cold agglutinin specificities but also essential for detecting the "new" type of cold agglutinins, obviously causing autoimmune haemolytic anaemia in vivo.
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PMID:Human cold agglutinins against "cryptic" erythrocyte antigens. 47 14

Coombs-positive anemia developed in cats inoculated with Haemobartonella felis. Cold agglutinins were detected in serum during the acute stage of the disease when anemia was present. The cold agglutinating activity was associated with IgM, was demonstrated at 4 C, and was abolished by treatment of sera with 2-mercaptoethanol. At 4 C, the sera from infected cats agglutinated or lysed parasitized autologous erythrocytes or normal erythrocytes pretreated with neuraminidase. These data indicate that cold agglutinins are associated with haemobartonellosis and suggest that immunologic responses to erythrocytic antigens have a role in the anemia.
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PMID:Cold agglutinins in cats with haemobartonellosis. 213 44

We report a case of malignant histiocytosis diagnosed by liver-spleen biopsy under laparoscopy. A 49-year-old woman was admitted to our hospital with thrombocytopenia, moderate anemia and hypoproteinemia. Her bone marrow findings revealed erythroid and megakaryocyte hyperplasia, and the serum ferritin concentration was 2,250 ng/ml though she had not received any blood transfusions. Ferrokinetics analysis showed the pattern of ineffective erythropoiesis, and the half-lives of erythrocytes and platelets were both shortened. Her hepatosplenomegaly gradually increased accompanied by increasing serum ferritin level to 10,000 ng/ml. Liver-spleen biopsy was carried out under laparoscopy and revealed infiltration of atypical histiocytes with erythrophagocytosis, which were positive for S-100 and ferritin but negative for lysozyme. The rate of glycosylation in whole serum ferritin, analyzed by using concanavalin-A binding method, showed that her glycosylated ferritin content was only 8.3%, whereas in sera after iron overloading, it was about 70%. Serum isoferritin profiles by isoelectric focussing were studied, and isoferritin pattern from malignant histiocytosis was the same as that in iron overloading after neuraminidase treatment. These findings suggest that serum ferritin is synthesized in proliferating histiocytes and released in the plasma as a nonsecretory type (nonglycosylated ferritin) in this case.
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PMID:[Mechanism of hyperferritinemia in a case of malignant histiocytosis]. 238 9

The mechanism by which senescent red blood cells (SRBCs) are eliminated from circulation by the reticuloendothelial system was investigated using the newly developed phagocytosis assay. Phagocytosis of SRBCs and Vibrio cholera neuraminidase (VCN) treated RBCs by autologous macrophages were significantly higher than that of unfractionated RBCs. The phagocytosis of VCN-treated RBCs was enhanced by pre-treatment of RBCs with freshly prepared autologous serum, but not with heat inactivated serum. These results suggest that the erythrophagocytosis is mediated by lectin-like receptors and complement receptors which are present on the surface of macrophages. We also studied the erythrophagocytic capacity of macrophages in the presence of tumor necrosis factor (TNF) as a model of the anemia due to acute inflammation. The phagocytosis of VCN-treated RBCs was enhanced with the addition of a small amount of TNF (1 U/ml). This result suggests that TNF enhances the destruction of damaged RBCs by activating the reticuloendothelial system.
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PMID:[Macrophages and erythrocytes]. 260 Oct 41

Representative specimens from two classes of Vertebrata Sub-Phyllum, Bufo paracnemis (amphibian) and Gallus domesticus (avian) were made anemic by phenylhydrazine treatment. Appearance of serum factors able to stimulate the proliferation of mammalian erythroid cells was tested. Normal and anemic sera from Gallus domesticus and Bufo paracnemis were fractioned by alcoholic treatment and assayed by the post-hypoxic mice method, showing null uptake of 59Fe. When assayed in semisolid cultures using bone marrow murine cells at different times of incubation (CFU-E and BFU-E colonies), anemia Gallus domesticus serum showed high stimulatory activity, while anemic Bufo paracnemis serum was unable to enhance erythroid proliferation. Gel filtration chromatography of partially purified avian samples on Sephadex G-150 showed three molecular entities responsible for biological activity in vitro, with an apparent molecular weight of 29, 14 and 10 KD respectively. They were submitted to several treatments and then tested for biological activity. All factors were heat stable, sensitive to neuraminidase treatment, while dithiothreitol caused loss of activity on low molecular weight proteins. These results suggest at least under these experimental conditions, the presence of analogous erythroid factors among homeotherms amniotas.
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PMID:Comparative studies of erythroid growth factors. 261 52

We report the first case of Haemolytic-uraemic syndrome (HUS) associated with Streptococcus pneumoniae meningitis. This supports a common pathogenic mechanism in HUS following infections by neuraminidase-producing organisms and in pneumococcal meningitis. We recommend that HUS must be considered in cases of renal failure and/or anaemia associated with pneumococcal meningitis, and that bacterial meningitis be considered in all patients with HUS and central nervous system involvement.
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PMID:Haemolytic-uraemic syndrome associated with Streptococcus pneumoniae meningitis. 274 37

Anemia, hyperbilirubinemia, and reticulocytosis subsequent to viral infection were present in a 32-year-old woman. The direct antiglobulin test was negative, and no unexpected antibodies were detected in pretransfusion tests. Rosettes of red cells (RBCs) around neutrophils were observed in peripheral blood smears, and a Donath-Landsteiner (D-L) test was positive. However, the patient did not show the classic features of paroxysmal cold hemoglobinuria (PCH). There was no hemoglobinuria, and in vivo hemolysis was not precipitated by cold. The D-L antibody was IgG, but classic anti-P specificity was not apparent. Rather, protease- or neuraminidase-treated RBCs, as well as certain sialic acid deficient RBCs of uncommon MN phenotypes, were not hemolyzed in D-L tests. Further, D-L antibody activity could be inhibited by MN sialoglycoprotein. These data support a diagnosis of chronic D-L hemolytic anemia, caused by an anti-Pr-like biphasic hemolysin.
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PMID:Donath-Landsteiner hemolytic anemia due to an anti-Pr-like biphasic hemolysin. 376 34

We have measured plasma N-acetyl-beta-D-glucosaminidase (EC 3.2.1.30) and neuraminidase (EC 3.2.1.18) activities as markers of glycosidase activity and immunoreactive trypsin (EC 3.4.21.4) levels as a marker of proteolytic potential in the plasma of normal and uraemic subjects. The levels of all of these enzymes are significantly elevated in the plasma of uraemic subjects when compared to normal. We have postulated that the combined attack of glycosidases and proteases on erythropoietin will lead to fragmentation of this glycoprotein hormone with loss of activity. This may be a major contributory cause to the anaemia of chronic renal failure.
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PMID:Increased plasma glycosidase and protease activity in uraemia: possible role in the aetiology of the anaemia of chronic renal failure. 390 90

Six strains of equine infectious anemia (EIA) virus propagated in equine leukocyte cultures were found to agglutinate horse erythrocytes. Concentrated virus material containing about 20 units of complement fixation (CF) titer showed hemagglutinating (HA) titers ranging from 4 to 8 units. The HA activity remained stable after ether treatment and was reduced by trypsin, formaldehyde and KIO4. Cesium chloride equilibrium density gradient centrifugation revealed two populations of hemagglutinin, one in the density range of 1.15-1.16 g/ml coinciding with a peak of CF antigen and the other at round 1.27 g/ml. However, after the antigen was treated with ether, hemagglutinin showed a single peak at about 1.27 g/ml. Hemagglutinin receptors on the erythrocytes were inactivated by trypsin and formaldehyde but their activity was enhanced by neuraminidase. Hemagglutination was inhibited by sera from horses infected with homologous strain for EIA virus. The hemagglutinin showed immunological properties similar to those of the hemagglutinin of guinea pig erythrocytes as reported in our previous paper.
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PMID:Hemagglutination of several strains of equine infectious anemia virus. 626 25

Bovine leukaemia virus (BLV) was found to agglutinate mouse erythrocytes. Under optimal conditions, including the use of neuraminidase-treated erythrocytes, 200 microgram/ml of BLV purified from the supernatant fluid of BLV-infected bat cells had haemagglutinating titres of about 512 units. BLV haemagglutination was drastically affected by pH and temperature; maximum agglutination occurred at pH 6 and 4 degrees C. That the BLV haemagglutinin is a glycoprotein was suggested by the fact that trypsin, potassium periodate or neuraminidase, but not lipid solvents or phospholipase C, significantly reduced the haemagglutinating (HA) activity of purified BLV. Furthermore, purified BLV glycoprotein of mol. wt. 51 000 (gp51) had HA activity. The receptors for BLV on mouse erythrocytes were inactivated by proteolytic enzymes but not by sodium deoxycholate or potassium periodate. Neuraminidase treatment of erythrocytes increase their agglutinability fourfold. Haemagglutination is a relatively sensitive test for detecting BLV glycoprotein because 0.4 microgram/ml of glycoprotein can be detected by this method. The pH and temperature sensitivity of the BLV HA reaction and specificity for mouse erythrocytes distinguish BLV from that of equine infectious anaemia virus and murine leukaemia virus, the other C type retroviruses known to have HA activity.
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PMID:Haemagglutination by bovine leukaemia virus. 627 77


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