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Biomedical subjects

S Mayer

Publications and source records attributed to S Mayer.

At least 127 records · Page 7Linked to original sources

[Discovery of hemoglobin J Baltimore in an episode of methemoglobinemia in an infant].

A case of a heterozygote for Hb J Baltimore is reported in a French family. This variant hemoglobin was coincidentally discovered during an episode of methemoglobinemia in a 6-week-old baby. The father and one of the brothers were also carriers of the trait. Hematological findings for all of them were normal. As Hb J Baltimore is a frequently occurring hemoglobin variant, we discuss: its possible role in the appearance of methemoglobin, and whether this mutation in different racial groups (Caucasians of West Europe, Canadians, and American blacks) has a common origin or more probably arises from a number of independent mutations.

Electrophoresis↗

Interferon enhanced natural killer function in Hodgkin's disease.

Natural killer (NK) cell activity of peripheral blood mononuclear cells from 19 untreated patients with active Hodgkin's disease and 22 age- and sex-matched healthy individuals was evaluated using classical K 562 cells as targets in a 4-h assay. A significant decrease was demonstrated in the patients (P less than 0.01) in accordance with previous data from the literature. Preincubation of effector cells with alpha leucocyte recombinant interferon (500 units/10(6) cells/ml) led to a significant increase in NK function in the patients (P less than 0.001). However, 4 patients still remained below the normal range and some patients were poor responders to interferon indicating that the mechanisms of depressed NK cell activity associated with Hodgkin's disease could not be overcome by interferon at least in some patients.

Adult↗

Natural HLA antibodies.

"Natural antibodies" directed against antigens of the Major Histocompatibility Complex have been observed in aged mice but very seldom in humans. It is likely that HLA natural antibodies are more common than previously supposed: our results suggest they may be found in 1% of normal blood donors. Most of these antibodies seem to be weak and can only be detected when B lymphocytes (BL) are used as target cells in the lymphocytotoxicity technique or when indirect immunofluorescence is used with peripheral blood lymphocytes (PBL). The behavior of these natural IgM antibodies was compared to that of weak immune IgG HLA antibodies detected in the same way. Absorption tests showed that "natural antibodies" were very specifically absorbed, whereas "immune antibodies" could also be absorbed by cells not carrying the specific antigen. Furthermore, about half of the "natural antibodies" detected to date carried the HLA-B8 specificity. Various hypotheses have been put forward to attempt to explain the appearance of these antibodies.

Adult↗

[Hepatitis B virus, serological markers of viral infections and humoral immunity in alcoholic cirrhosis].

In order to define the role of hepatitis B virus (HBV) in alcoholic liver disease and to study the relationship between HBV and other common viruses, the serological markers of viral disease (HBV, Rubella, Polio, Herpes, and Cytomegalovirus-CMV) were compared in 163 patients with alcoholic cirrhosis (group C), 100 patients with alcoholic steatosis (group S) and in 168 non-alcoholic control subjects (group NA). A significantly increased prevalence of HBV markers in group C was related to the presence of anti-HBc antibodies, in 10.5 p. 100 of cirrhotic patients, vs. 1.2 p. 100 in group S and 1 p. 100 in group NA (p less than 0.01). In cirrhotic patients with HBV markers (HBV +) incidence of alcoholic hepatitis was 4 times lower and the total duration of alcohol overconsumption was significantly lower than in cirrhotic patients without these markers (HBV-). Hepatic function tests were not different in HBV + and HBV- cirrhotic patients, excepted for the ASAT/ALAT ratio (1.55 +/- 0.10 vs. 1.92 +/- 0.12; p less than 0.05). Prevalence of anti-CMV antibodies, and anti-herpes greater than 1/100 antibodies, was significantly increased in S and C groups (p less than 0.01). Anti-Rubella, Polio, and CMV antibody titers were higher (p less than 0.05) in HBV + than in HBV- cirrhotic patients. In cirrhotic subjects, titers of these 3 anti-virus antibodies were not related to alcoholic hepatitis or to IgG and IgM concentrations.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Viral↗

HLA antigens in multiple sclerosis in Alsace.

The distribution of HLA antigens A, B, C and DR was studied in 69 native Alsatian multiple sclerosis (MS) patients. Antigen DR2 was high in MS compared to healthy control subjects, as is known. Given antigens were more frequently, and, above all, more closely linked with certain clinical and organic parameters. Antigens A3, B7 and B40 were preferentially associated with progressive forms, and A32 with remitting forms. B7 may be predictive of the prognosis, as it was correlated with disease severity. B7 and DR2 were more frequent in MS patients presenting intrathecal immunoglobulin synthesis. Sex appeared to be a fundamental factor in the clinical expression of MS, interacting closely with the HLA system. These findings confirm the multi-factor etiology of MS. Several MS susceptibility genes may exist near the HLA complex, and their expression may modulate the clinical and organic signs of MS. Studies of this sort should be carried out on ethnically and geographically homogeneous populations.

Adult↗

[Prevalence of HLA-A and -B antigens, anti-HBc and -HBs antibodies in alcoholic hepatopathies].

The frequency of 26 HLA-A and B antigens and of antibodies to the hepatitis B core antigen (anti-HBc) and surface antigen (anti-HBs) has been studied in 150 alcoholic patients divided into 3 groups: I) n = 50, isolated hepatic steatosis; II) n = 50, acute alcoholic hepatitis +/- cirrhosis; III) n = 50, cirrhosis without acute alcoholic hepatitis. For the control group 184 blood donors were selected. In all these subjects, as in all the alcoholic patients, the Alsatian origin of four grand parents was proved. An increased frequency of HLA-B15 was observed in group III (34 p. 100) compared to the control group (9.8 p. 100) (corrected p less than 0.001). There was no significant difference between the four groups for all the other HLA antigens. In group III, the prevalence of anti-HBc and/or anti-HBs was higher in patients with HLA-B15 (64.7 p. 100) than in patients without this antigen (15.1 p. 100) (p less than 0.001). In groups I and II, there was no significant difference. These results suggest that there is a genetic predisposition to cirrhosis without acute alcoholic hepatitis, dependent on HLA-B15 antigen. This predisposition could involve the hepatitis B virus.

Acute Disease↗

[ELISA on cells. Review of current technics].

Immunoenzymological techniques are used to detect monoclonal antibodies directed against cell membrane antigens. The different materials used, the method of utilizing cells, the choice of the appropriate enzyme and the different technical variations are described. The advantages and disadvantages of each method are discussed.

Animals↗

Stage-related decrease in natural killer cell activity in untreated patients with mycosis fungoides.

Natural killer activity of peripheral blood mononuclear cells against the human cell line K 562 was evaluated in 11 patients with mycosis fungoides and simultaneously in 10 age- and sex-matched controls. In the patient group, nine had no previous treatment and in two topical therapy had been discontinued more than 3 months before. None had any associated disease or concurrent therapy that could interfere with the immune system. Patients with early disease showed a mean specific lysis and a range of individual data similar to the controls whereas patients with advanced disease had a significant defect of natural killer activity at effector: target ratios of 100 : 1, 50 : 1, and 25 : 1, as shown by the Mann-Whitney test. Preincubation of effector cells with alpha-interferon for 1 h in a single patient with low natural killing capacity led to a clear increase of the specific lysis, suggesting reduced functional activity rather than depletion of effector cells.

Adult↗

Membrane markers, karyotypic abnormalities, ultrastructure and functional properties of lymphocytes in a case of 'D-cell' chronic lymphatic leukemia.

D cells are lymphocytes bearing both receptors for the third complement component and the ability to form spontaneous rosettes with SRBC. We report the case of a patient with a D-cell chronic lymphatic leukemia who presented a long evolution without treatment and whose leukemic cell characteristics have been extensively studied. Cytogenetic analysis showed numerous karyotypic abnormalities among leukemic cells; all metaphases were hypodiploid and arranged in four different clones; seven marker chromosomes were present. The cells were found to bear human T-cell specific antigen, the T helper/inducer phenotype, HLA-A and HLA-B determinants, but no HLA-DR antigens. They displayed a high proliferative response to PHA and Con A, no response to PWM stimulation, and possibly the capacity of allogeneic stimulation in the mixed lymphocyte culture system. Assays for cell-mediated cytotoxicity in the CML system, and for K and NK activities were negative.

Antigens, Surface↗

[Comparative study of three presentations for research on HBs antigen by the immunoenzyme technique].

The authors present the results of a study comparing the detection of HbSAg by enzyme immunoassay using the following three different commercial kits and their corresponding apparatus: Auszyme II, Quantum II from Abbott; Enzygnost micro Elisa, Elisa Processor from Behring; Hepanostika, washer and reader micro Elisa system from Organon. The purpose of the study is to determine the sensitivity and specificity of the reaction and the extent of automation of this method. The sensitivity and specificity of the 3 kits are compared with those of a reference technique, the radioimmunoassay Ausria II, Abbott. The sensitivity of Auszyme II is equivalent to that of Ausria II and is approximately 0.2 mg/ml. The other two kits are somewhat less sensitive. The proportion of false negative is less than 1%, but with all 3 kits it is necessary to verify a negative result. The results of this study confirm the high level of sensitivity and specificity of the enzyme immunoassay for the detection of HbSAg in the serum or plasma of blood donors. This technique therefore offers an alternate method of HbSAg detection to laboratories which cannot or prefer not to use a radioimmunoassay.

Autoanalysis↗

[Biological studies and research of immunologic deficiencies in blood donors from a prison environment].

The prison population may be considered as a population at risk for AIDS. Biological parameters were studied in order to detect significant anomalies commonly observed in AIDS patients. With respect to are age matched control population of donors, there are no statistically significant differences concerning the nutritional and inflammatory states of the two populations. The investigation of the humoral immunity shows comparable levels of circulating antibodies in the two groups: a high level of anti-cytomegalovirus and anti-herpes antibodies is more frequently found in the penal population. The markers for hepatitis B were also studied. None of the individuals is a carrier of the HBs antigen. The percentage of individuals having biological markers of hepatitis B is higher in the at risk group (45%) than in the control group (10%). The evaluation of the cell-mediated immunity shows that there are no significant differences between the mean values found in the two groups for OKT3, T11, OKT4 and OKT8. There is no inversed OKT4/OKT8 ratio in the at risk group while one donor in the control group shows an inversed OKT4/OKT8 ratio.

Acquired Immunodeficiency Syndrome↗

Fetal immunization against the mother's lymphocytes. A report of two cases.

In 2 cases the child's serum at birth contained a lymphocytotoxic antibody whose specificity did not correspond to the maternal serum's specificity. Further investigation suggested that the newborns were immunized against their mother as the antibodies were directed against maternal antigens.

Antibody Specificity↗

Depressed NK cell activity of peripheral blood mononuclear cells in untreated hodgkin's disease: enhancing effect of interferon in vitro.

Natural killer (NK) cell activity of unseparated peripheral blood mononuclear cells from 30 untreated patients with Hodgkin's disease and 22 age- and sex-matched normal controls was evaluated using the classical K 562 cells as targets. A significant defect was demonstrated in the patients with stage I-II and seemed to be more profound in patients with advanced disease (stage III-IV) and in those with B symptoms. The differences between subgroups of patients, however, were not statistically significant, mostly because of the wide dispersion of individual data. Pre-incubation of effector cells with alpha A leucocyte recombinant interferon led to a clear increase in NK cell activity in 4 of 6 patients tested, showing that depressed NK activity in Hodgkin's disease is still susceptible to the enhancing effect of interferon, at least in some patients.

Adolescent↗

[Iron overload in a beta thalassemia heterozygote of the intermediate type in a subject of Alsation origin. Results of iron chelation treatment].

Heterozygous beta thalassaemia with microcytic anaemia (hemoglobin concentration 77 g/l) has been recognized in a 49 year-old woman of Alsatian extraction. A long history of microcytic anaemia had led to inadequate oral iron treatment before the patient was referred to us because of the persisting microcytic anaemia and iron loading. Indeed the patient also had haemosiderosis with a high transferrin saturation (73%) and markedly elevated ferritinaemia (1,114 micrograms/ml). Ferrokinetic data showed increased plasma iron turnover, early transfer of iron to the liver and evidence of ineffective erythropoiesis. She was treated with desferrioxamine (3 g every three days subcutaneously) and serum ferritin levels gradually decreased together with transferrin saturation. After 15 months serum ferritin and transferrin saturation were within the normal range. Several hypotheses are discussed to explain why this patient had haemosiderosis associated with heterozygous beta thalassaemia. The propositus was found to be HLA-A3, which is strongly associated with idiopathic haemochromatosis. Her sister also carries HLA-A3 with heterozygous beta thalassaemia but she has neither anaemia nor iron overload. Thus double heterozygotism is unlikely in our patient.

Anemia↗