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Biomedical subjects

A Paraf

Publications and source records attributed to A Paraf.

At least 37 records · Page 2Linked to original sources
PubMed1985

A method of purifying sheep sIg+ lymphocytes as a tool for class II MHC antigen analysis.

A method is described for the purification of sheep lymphocytes carrying class II MHC antigens. After incubation of purified blood lymphocytes on anti-IgM-coated petri dishes, the adherent fraction contained 95% sIg-positive cells determined by immunofluorescence. When tested with cross-reacting anti-class II (bovine and human) monoclonal antibodies, more than 95% of these cells were positive either by immunofluorescence or cytotoxicity. This technique will permit studies of the polymorphism of sheep class II antigens.

Animals↗
PubMed1985

[Granulopoiesis in the alcoholic and cirrhotic patient. Exploration of neutropenia in cirrhosis using bone marrow cultures and a hydrocortisone test].

Twenty per cent of 60 patients with cirrhosis (55 alcoholic patients) had neutropenia (defined as neutrophil polymorphonuclear (NP) count under 2,000/mm3). The authors tried to define the mechanism of this neutropenia and compared it with the acute bone marrow cytotoxicity of alcohol. They found that bone marrow neutrophil colony growth was normal in 7 cases of cirrhosis compared to 7 controls (with and without cirrhotic serum incubation). On the other hand, the granulocyte response to hydrocortisone test was less marked than in controls. This result suggests involvement of the late maturation process of NP and delayed release from bone marrow.

Agranulocytosis↗
PubMed1984

Hepatoma after thorotrast. Morphological and autoradiographic data.

Two women, respectively given thorotrast 30 and 40 years ago, died of hepatoma. The spleen and liver of one and the liver of the other were studied by morphological, macro- and micro-autoradiographic methods. The part played by thorotrast in the neoplasic process and its effect on the mechanism of tumour induction are discussed.

Aged↗
PubMed1983

[Erythrocyte filtrability in liver cirrhosis].

In view of the frequent erythrocyte abnormalities found in liver cirrhosis, erythrocyte deformability was studied in 62 patients. Deformability was determined by the initial filtration flow technique using a Hemorheometer. Results are given as a rigidity index (IR), which is characteristic of the average individual RBC. Deformability was significantly reduced in patients with cirrhosis. No correlation was found with the often increased MCV. A significant positive correlation was found between IR and the cell membrane free cholesterol/phospholipid ration, as the increase in cell rigidity is mainly due to a decrease in the cell membrane sphingomyelin content. The role of reduced RBC deformability in liver cirrhosis anemia still awaits elucidation.

Erythrocyte Indices↗
PubMed1983

Differential cytostatic effect of interferon on murine BALB/c B- and T-cell tumors.

The cytostatic effect of murine interferon (IFN) on several BALB/c-derived B- and T-cell tumor cells was examined. After incubation for 1 h in vitro with 1000 U of IFN, followed by intraperitoneal inoculation, tumor formation was not decreased in the case of B cell tumors or Lyt-1+2- or Lyt-1+2+3+ T cells tumors. Under the same conditions, the onset of tumor formation for Lyt-2+3+ T-cell tumors was delayed and the final incidence decreased. When the effect of IFN on cell multiplication in vitro was examined, Lyt-2+3+ T-tumor cells were found to be more sensitive to the cytostatic effect of IFN than Lyt-1+2+3+ T-tumor cells. This shows that the sensitivity of lymphocyte-derived tumor cells to the cytostatic effect of IFN is influenced by the type of differentiation of the cells.

Animals↗
PubMed1983

Comparison of 11C-L-methionine uptake by the parotid gland and pancreas in chronic pancreatitis studied by positron emission tomography.

L-methionine uptake by the parotid gland and pancreas has been compared in 27 patients using a non-invasive methodology. L-methionine was labelled with 11C, a positron emitter with a short half life produced in a cyclotron. 11C-L-methionine concentration was measured in the parotid glands and in the pancreas by external detection using a positron emission tomographic system. 11C-L-methionine uptake by the parotid glands was 4.3 X 10(-3) +/- 1.9 X 10(-3)% of the injected dose per millilitre of tissue (mean +/- SD) in a group of 11 normal non-alcoholic subjects. The uptake was 3.6 +/- 1.3 (X10(-3) in a group of nine alcoholic subjects without pancreatic disorder and it was 4.9 +/- 1.5 (X10(-3) in a third group of seven patients with chronic pancreatitis. These values did not significantly differ. In contrast median pancreatic uptake of 11C-L-methionine was nil in chronic pancreatitis and was lower than that seen in normal subjects (15.3 X 10(-3)% ml, p less than 0.001) and in alcoholic subjects (11.5 X 10(-3)% ml, p less than 0.002). Thus neutral long chain amino acid transport in the parotid gland appears to be independent of that in the exocrine pancreas in chronic pancreatitis. This absence of relationship between the parotid gland and the pancreas in pancreatic disease is in contradiction with the demonstration made in animals of an interaction between these two glands. These results, however, are in agreement with the conclusions drawn from the data collected from the saliva test used by several authors.

Adult↗
PubMed1983

Relationship between cytidine 5'diphosphocholine epitope density on ovalbumin and IgE antibody responses compared to other isotypes.

Ovalbumin was covalently substituted by 6, 18 and 20 residues of Cytidine 5'diphosphocholine per molecule. When injected into BALB/c mice, these products induced distinct immunogenic responses. Without any residue, or with six residues, ovalbumin induced hemagglutinating antibodies (1/256, 21 days after injection) and a response to the passive cutaneous anaphylactic reaction (1/400, 21 days after injection). By contrast, with 18 or 20 residues, ovalbumin brought about the appearance of only a weak titer of hemagglutinating antibodies (1/64, 21 days after injection); no response to the passive cutaneous anaphylactic reaction was observed. No anti-cytidine 5'diphosphocholine antibodies were detected by either reaction. Thus epitope density plays a major role in the IgE immune response to PC-OA.

Animals↗
PubMed1982

Characterization of a beta-actinin-like protein in purified non-muscle cell membranes. Its activity on (Na+ + K+)-ATPase.

Treatment by EDTA of purified plasma membranes from MF2S cells (a variant of the murine plasmacytoma MOPC 173) solubilized proteins and increased by a 1000-fold the sensitivity of (Na+ + K+)-ATPase to ouabain. When added back with Ca2+ to treated plasma membranes, these EDTA-solubilized proteins restored the initial sensitivity of the enzyme to its inhibitor. We report the purification of a protein of Mr 32000, isolated from the EDTA-treated membrane supernatant. This protein was purified by a one-step procedure involving a preparative polyacrylamide gel electrophoresis without detergent. In the presence of Ca2+ it was able to restore the original sensitivity to ouabain of (Na+ + K+)-ATPase from EDTA-treated membrane. This protein was shown to be similar to the beta-actinin described by Maruyama by the following criteria: (1) molecular weight and amino acid composition; (2) cross-reactivity with their respective antisera; (3) in the presence of Ca2+ the same quantitative biological activity on ouabain sensitivity of the (Na+ + K+)-ATPase. A possible interaction between beta-actinin, calmodulin and membrane-bound (Na+ + K+)-ATPase is discussed.

Actinin↗
PubMed1982

The role of positron emission tomography in the detection of pancreatic disease.

Positron emission tomography (PET) was used to assess possible pancreatic disease in 100 patients. Following injection of 10-15 mCi (370-740 MBq) of 11C-L-methionine, 4-12 transverse sections 2 cm thick were obtained. In 85 patients with a definite diagnosis (45 normal, 9 acute pancreatitis, 18 chronic pancreatitis, and 13 cancer), PET showed a sensitivity of 85.0%, a specificity of 97.8%, and an accuracy of 91.8%, higher than with transmission computed tomography (CT) or ultrasonography, despite relatively low spatial resolution; this can be explained by the fact that exocrine pancreatic function was altered prior to morphological change. In 22 normal subjects, 0.011 +/- 0.003% (mean +/- S.D). of injected 11C was found in 1 ml of liver tissue and 0.015 +/- 0.005% in 1 ml of pancreatic tissue; the pancreas-to-liver concentration ratio was 1.3 +/- 0.4. Hepatic 11C concentration was identical in the four groups of patients. Pancreatic uptake of 11C-L-methionine was significantly lower in patients with chronic pancreatitis (n = 13) and pancreatic carcinoma (n = 10) (p less than 0.001); however, it was not possible to distinguish cancer from chronic pancreatitis because the same functional alteration occurred in both.

Carbon Radioisotopes↗
PubMed1982

Receptors for peanut agglutinin in lymphocytes from patients with cirrhosis of the liver.

A population of peripheral blood lymphocytes exhibits specific receptor for the peanut lectin (Arachis hypogaea). In control subjects, this population represents 1.3% of all lymphocytes while it represents 13% in patients with alcoholic cirrhosis. The percentage of lymphocytes expressing this receptor appears to be correlated with hypoalbuminemia and the erythrocyte sedimentation rate, in these patients. Furthermore, a higher percentage of peanut positive lymphocytes was found in cirrhotic patients who subsequently died than in those who survived.

Adult↗
PubMed1981

Stimulation by tubulin of an adenylate cyclase from murine plasmacytoma.

Different brain tubulin preparations were shown to stimulate membrane-bound adenylate cyclase from the murine plasmacytoma MOPC 173. Purified tubulin devoid of microtubule-associated proteins and of nucleoside-diphosphate kinase activity was responsible for this stimulation. Activation of the basal adenylate cyclase activity occurred in less than 2 min at 32 degrees C and was amplified by a 4 degree C preincubation of tubulin with plasma membranes. Tubulin affected the Km and the V of the enzyme and was shown to be associated with the membrane during the activation phenomenon. Tubulin was more active on the basal adenylate cyclase activity than that stimulated by fluoride or guanosine 5'-[beta, gamma-imido]triphosphate. GTP has no effect on the tubulin-stimulated enzyme.

Adenylyl Cyclases↗