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H Jouin

Publications and source records attributed to H Jouin.

66 records · Page 4Linked to original sources
PubMedDate not supplied

A monoclonal antibody recognizes a subset of the H-2Dd mouse major class I antigens.

Binding studies and competition experiments have shown that a monoclonal antibody (mAb) named 28-8-6 recognizes only 5 to 10% of the cell surface Dd molecules. The molecules detected by 28-8-6 mAb appear to be genuine H-2Dd antigens on the basis of their MW and isolectric points. In addition, the detectability of the subset of cell surface Dd molecules by 28-8-6 does not depend on their degree of glycosylation nor on the presence of mouse beta-2-microglobulin. Several interpretations are discussed. mAb 28-8-6 might detect a particular conformation or a particular chemical derivatization of otherwise normal H-2Dd molecules. Also, because the epitope recognized by 28-8-6 lies close to the peptide binding site, it is possible that mAb 28-8-6 recognizes a subset of Dd molecules bearing a certain category of self peptides.

Animals↗
PubMedDate not supplied

The recombinant human interferon-gamma receptor is fully functional in a human x murine hybrid containing human chromosome 21.

It has previously been shown that stimulation of class I MHC antigen expression by human interferon gamma (Hu-IFN gamma) depends on the presence of both human chromosomes 6 and 21. Even although the presence of human chromosome 6 results in normal expression of the IFN gamma receptor on the cell surface, chromosome 21 is required for this biological response. Here, we transfected the cDNA encoding the Hu-IFN gamma receptor into a mouse cell line, L(tk-), and into a mouse x human hybrid, GM08, containing the human chromosome 21 as the only human genetic material. Two clones, L-gamma R.8 and GM08-gamma R.9, were tested for different biological responses to Hu-IFN gamma. Only the hybrid containing the human chromosome 21 (GM08-gamma R.9) exhibited a biological response when assayed for the stimulation of murine class I MHC antigen expression by Hu-IFN gamma. Moreover, transcriptional induction of 2'-5'-oligoadenylate synthetase and 1-8 genes, as well as antiviral protection, were observed only in the GM08-gamma R.9 transfectants. These results show that human chromosome 21 encodes a factor which mediates different biological activities of Hu-IFN gamma.

Blotting, Northern↗
PubMedDate not supplied

Changes in recognition of Plasmodium falciparum antigens by human sera depending on previous malaria exposure.

Naturally acquired immunity against Plasmodium falciparum malaria was analysed by immunoprecipitation and electrophoretic analysis of FUP-1 strain antigens by sera from individuals with different histories of exposure to malaria. Sera from individuals in the process of either acquiring natural resistance (from different age groups in a village of Upper Volta) or losing acquired resistance (adults travelling from hyperendemic areas of Africa to France) were compared. From electrophoretic patterns, it was apparent that two parasite peptides of MW 96 and 100 Kd were preferentially recognized by putatively resistant individuals. Analysis of the reactivity of adult sera from different parts of the world with FUP-1 antigens showed that there were no major geographically restricted antibody specificities. In particular, antibodies reactive with these two peptides were identified in sera of diverse geographic origins. These 96- and 100-Kd peptides of P. falciparum may therefore be antigens related to naturally acquired immune resistance and common to P. falciparum strains of different geographic origin.

Adolescent↗
PubMedDate not supplied

[Non-surgical treatment of cysts and pseudocysts of the pancreas. A study of a series of 33 cases].

Pancreatic cysts and pseudocysts had to be treated by surgery until 15 years ago. Nowadays they can be aspirated (or drained) either endoscopically or by ultrasonic and computed tomographic guided punctures. The aim of this study was to see if these non-surgical treatments were efficient enough among the actual treatments. From 1984 to 1988, 33 patients were admitted in one single institution with a pancreatic cyst or pseudocyst, 22 of which were a consequence on an acute pancreatitis and 11 complicated a chronic pancreatitis. Ten cysts were connected with the Wirsung channel while 11 others were not, but the ERCP failed to give any accurate information on this point in 12 cases. As a first treatment, we abstained of any invasive procedure in 9 cases, 18 were treated by percutaneous aspiration guided by ultrasound and 6 patients underwent surgery. The mean follow-up was 30 months. All the patients who had no treatment remained symptom free; their cysts improved in 5 cases and disappeared in 4 cases. Among the cysts treated by percutaneous aspiration, 4 had to be operated, 5 disappeared, 3 improved and 6 recurred; the percutaneous aspiration obtained a lasting symptoms' relief for these patients, whatever the connection the cyst had with the Wirsung channel. This study suggests that percutaneous aspiration or drainage guided by ultrasound may be a treatment of the highest quality for acute and chronic pancreatitis cystic formations. However, it seems to act upon the symptoms rather than upon the cystic formations themselves.

Adult↗
PubMedDate not supplied

[Efficacy of endoscopic pneumatic dilatation in achalasia. Medium-term results].

During a seven-year period, thirty patients with achalasia of the esophagus were treated by pneumatic dilatation without complications. Only twenty patients could be followed with a mean follow of 32 +/- 23 months after their initial dilatation. Excellent to good results were obtained in more than 75 p. cent of the group. Most patients have not required a further dilatation. This study suggest to propose a regular supervision of these patients by clinical examination, esophageal manometry and endoscopy.

Adult↗
PubMedDate not supplied

[Esophagogastroduodenal localizations of Crohn's disease are frequent].

The purpose of this study was to determine the endoscopic features, actual frequency and consequences of upper digestive involvement in Crohn's disease (CD). Between April 1973 and April 1985, one or several upper digestive tract endoscopies with biopsies were performed in 129 of 195 patients admitted for ileal and/or colorectal CD. Endoscopic lesions were small and superficial: aphtous and superficial ulcerations, or erythematous areas. The diagnosis of upper digestive involvement was probable in 36 of the 129 patients who underwent upper endoscopies (28 p. 100), certain (microscopic evidence of granuloma) in 21 patients (16 p. 100). Lesions were isolated or multifocal but their preferential sites were the antrum and proximal duodenum. Histologic study of biopsies showed that granuloma were as frequent in upper as in lower intestinal lesions of CD. A frequency of 20 p. 100 seems to us to be more correct than the 5 p. 100 usually admitted. In our experience, upper digestive involvement in CD could not be regarded as a pejorative prognostic factor. It was sometimes possible to identify colitis or a peptic ulcer disease as a lower or upper digestive manifestation of CD, respectively.

Adult↗
PubMedDate not supplied

[Study of X antigen of Salmonella typhi responsible for the production of protective antibody towards chick embryo].

Laboratory animals are not sensitive to human S. typhi strain (O+ Vi+). But the chick embryo is very susceptible to infection by this strain. This property can be used to test protective activity of immuno sera. Several antigenic fractions have been prepared from Ty6S strain (0- Vi+) by washing methods. The " outer layer " of the bacteria is easily removed by NaCl 0,5 M. Injected in rabbits this preparation produces the synthesis of protective antibodies. The active antigen X is spun down with the Vi antigen. The relation of X antigen to Vi antigen is being studied.

Animals↗