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Biomedical subjects

M Peuchmaur

Publications and source records attributed to M Peuchmaur.

At least 109 records · Page 6Linked to original sources
PubMed1990

Cystic benign lymphoepithelial lesion of the salivary glands in HIV-positive patients. Report of two cases with immunohistochemical study.

Two cases of cystic benign lymphoepithelial lesions (CBLL) of the submandibular and parotid glands occurring in HIV-positive patients are reported. The clinical and pathological criteria are defined and the differences from Sjögren's syndrome discussed. The presence, in the epithelial component, of T-cells labelled by the human mucosal lymphocyte antibody argues for a primary involvement of epithelial structures in CBLL, the lymphoid hyperplasia occurring secondarily.

Adult↗
PubMed1990

Peripheral T-cell lymphomas have a worse prognosis than B-cell lymphomas: a prospective study of 361 immunophenotyped patients treated with the LNH-84 regimen. The GELA (Groupe d'Etude des Lymphomes Agressives).

The prognostic significance of phenotype in malignant lymphomas (ML) is a matter of controversy. Here we analyze the clinical presentation, response to treatment, and survival of the 361 phenotyped patients with ML who were treated by the LNH-84 regimen. Histologic subtypes were diffuse-small cell in 10 patients, diffuse mixed in 69, diffuse large-cell in 177, immunoblastic in 94, and anaplastic large-cell in 11. One hundred and eight patients (30%) had a peripheral T-cell ML and 253 (70%) a B-cell ML. Most of B-cell MLs were of diffuse large-cell type, and the T-cell MLs were distributed among diffuse mixed and immunoblastic subtypes. T-cell MLs had an aggressive presentation with more patients having advanced stage (21% versus 41% stage II, 53% versus 45% stage IV, p = .0002), and B symptoms (58% versus 42%, p less than .01). The only significant difference in clinical manifestations were the higher frequency of gastrointestinal involvement in B-cell MLs (20% versus 2%, p less than .0001) and the more frequent spleen (39% versus 21%, p = .0005) and skin (19% versus 3%, p less than .0001) involvement in T-cell MLs. There was no difference in response to the LNH-84 regiment between the two subgroups, but T-cell ML patients relapsed at a higher rate (43% versus 29%, p less than .001). T-cell ML patients have a significantly shorter freedom-from-relapse (FFR) survival (median: 34 months versus not reached, logrank test: p = .002) and a non-significant shorter overall survival (median: 42 versus 50 months).(ABSTRACT TRUNCATED AT 250 WORDS)

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1990

Production of interleukins in human immunodeficiency virus-1-replicating lymph nodes.

To document the in vivo interactions occurring between the immune system and HIV replicating cells, we analyzed using in situ hybridization the production of IL-1 beta, IL-6, IL-2, and INF-gamma in eight hyperplastic lymph nodes from HIV-1 infected patients. Numerous IL-1 beta- and IL-6-producing cells associated in clusters were detected in sinuses. Few individual IL-1 beta- and IL-6-producing cells were present in interfollicular and follicular areas. IL-2- and INF-gamma-producing cells were observed in all lymph node compartments, with a selective enrichment in germinal centers. The amount and distribution of IL-1 beta, IL-6-, and IL-2-producing cells in HIV lymph nodes were not different from those found in six HIV unrelated hyperplastic lymph nodes. In contrast, a higher level of INF-gamma production was observed in HIV-1 lymph nodes. The CD8+ cells that accumulate in germinal centers of HIV lymph nodes (and not in non-HIV germinal centers) were actively involved in this INF-gamma production. INF-gamma synthesizing cells were in direct contact with cells containing HIV core antigens and HIV RNA. Thus a high INF-gamma production may characterize anti-HIV T cell immune response, potentially contributing to control of viral spreading as well as to the development of follicle lysis.

Adult↗
PubMed1990

IL-2 mRNA expression in Tac-positive malignant lymphomas.

Expression of the IL-2 receptor (Tac antigen/CD25) is documented in malignant lymphomas. Because IL-2 is a major lymphocyte growth factor, an IL-2-dependent growth could be involved in the proliferation of Tac-positive lymphomas. Indeed such a mechanism has been demonstrated experimentally for the growth of T-cell lines. To investigate this point in human lymphomas, we used in situ hybridization to analyze the expression of the IL-2 gene in 20 non-Hodgkin's lymphomas, among which 12 expressed the IL-2 receptor. Nine of these were anaplastic large cell lymphomas expressing the Ki-1-related antigen. We here show that IL-2-producing cells are present in all the lymphomas we analyzed. As a mean, there is no significant difference in the percentage of IL-2-producing cells between Tac-positive and -negative lymphomas. However, the level of IL-2 production is highly heterogeneous in both groups, and the highest density of IL-2-producing cells was observed in 2 Tac-positive lymphomas. Simultaneous detection of cellular antigens and of IL-2 mRNA demonstrates that IL-2 is produced by reactive T cells rather than by tumor cells. These results suggest that if IL-2 is involved in the growth of Tac-positive lymphomas, it acts as a paracrine, rather than an autocrine, factor.

Adolescent↗
PubMed1990

[Treatment of aggressive non-Hodgkin's lymphoma in aged patients with a combination of methyl-GAG, etoposide and prednimustine].

The authors report the results of a chemotherapy regimen of methyl-GAG, etoposide and prednimustine in 21 elderly patients (median age = 78 years) with aggressive non-Hodgkin's lymphoma. Sixteen patients responded (11 complete remissions, 5 partial remissions) with minor toxic side-effects. This regimen could be proposed for patients whose age and/or cardiovascular status prohibit treatment with usual anthracycline-containing chemotherapy programs.

Aged↗
PubMed1989

Visualizing interleukin 2 gene expression at the single cell level.

To analyze the expression of the interleukin (IL)2 gene at the single cell level, we have constructed a chimeric gene in which the regulatory sequences from the mouse IL2 gene were fused 5' proximal to the coding region of the Escherichia coli beta-galactosidase (lacZ) gene. Once stably introduced into a T cell hybridoma, the IL 2-lacZ reporter gene was shown to display a pattern of induction similar to the one observed for the resident IL 2 gene. Two points emerged from monitoring IL 2 expression for the resident IL2 gene. Two points emerged from monitoring IL 2 expression at the single cell level. First, upon activation the expression of the IL2-lacZ gene appears asynchronous. Second, at the peak of induction the percentage of beta-galactosidase+ cells never reached 100% and the level of beta-galactosidase reached among positive cells was highly heterogeneous within a cloned population of T cells. In combination with the possibility to sort viable lymphocytes according to lacZ expression, the IL2-lacZ reporter gene described herein should provide a way to isolate somatic cell mutants deficient in signal transduction by the T cell antigen receptor complex.

Animals↗
PubMed1989

Analysis of mucosal bladder leucocyte subpopulations in patients treated with intravesical Bacillus Calmette-Guerin.

Immunohistochemical techniques were used to investigate leucocyte subpopulations in the bladders of patients with superficial transitional cell carcinoma treated with BCG Pasteur. Leucocyte subsets were enumerated with a panel of monoclonal antibodies which included CD3, CD4, CD8, TQ1, Leu7, CD15, HLA-DR, CD25, CD22. We demonstrated in the bladders of patients treated with BCG a particular lymphocyte population; the major subset was an inducer (CD4+, TQ1-) which was activated (CD25+, HLA-DR+) and associated with polymorphonuclear eosinophils. There was neither inducer of suppression nor major cytotoxic/suppressive subsets. CD8+ and NK cells could not be the primary mediators of BCG activity. These data supported the hypothesis of a helper T lymphocyte activity associated with lymphokine production and activation of effector killer cells.

BCG Vaccine↗
PubMed1989

Squamous cell carcinoma in situ developing in dermoid cyst of the ovary. Report of a case with laminin immunohistochemical staining demonstrating basement membrane integrity.

Among malignancies arising in dermoid cyst of the ovary, squamous cell carcinoma in situ is very unusual and set a problem of diagnosis and prognosis. In fact this diagnosis is very difficult and here we report the case of a 30-year-old woman with a squamous cell carcinoma in a dermoid cyst of the right ovary for which laminin immunohistochemical staining allowed us to prove beyond any doubt the in situ character. This demonstration is of great importance because the prognosis of a squamous cell carcinoma in dermoid cyst depends on the degree of penetration of the tumor; so in this young patient a conservative surgery could be carried out. Four years later the very good evolution confirms the accuracy of the diagnosis of squamous cell carcinoma in situ in dermoid cyst and emphasizes the benefit of laminin labelling in order to rule out the possibility of invasive carcinoma.

Adult↗
PubMed1989

HIV-associated endometritis.

Using immunohistochemical staining, in situ hybridization and a combination of both, we demonstrate here the replication of HIV in the endometrial stroma. Infected cells do not belong to the T-lymphocyte lineage but rather to a monocyte-macrophage cell type. This report suggests a possible relationship between HIV infection and endometritis. Moreover, HIV replication in endometrial tissues could play a role in heterosexual and materno-fetal transmission.

Acquired Immunodeficiency Syndrome↗
PubMed1989

[Analysis of lymphocyte subpopulations of the bladder following endovesical immunotherapy using BCG].

The authors studied, by means of immunohistochemical analyses, the lymphocyte subpopulations in bladder biopsies from 20 patients treated for a urothelial bladder tumour (Tis TA, T1) by intravesical BCG (group A). The biopsies were taken from optically healthy zones and were then frozen. The lymphocyte populations in the urothelium and chorion were studied by means of monoclonal antibodies T3, T4, T8, TQ1, Leu-7, OKM-1, HLA-DR, TAC, Pan-B. Four patients without bladder cancer constituted the control group (group B) and 10 patients with bladder cancer not treated by intravesical BCG constituted group C. In group A, the T4 + TQ1 lymphocytes predominated in the urothelium and in the chorion. An inversion of the T4/T8 ratio was observed in the urothelium of groups B and C (p less than 0.01) and in the chorion of group B (p less than 0.01). There was no significant difference in the T4/T8 ratio in the chorion in groups A and C. In group A, 17 patients expressed the presence of receptors for interleukin 2 (TAC + HLA-DR) on their T lymphocytes. In these cases, the lymphocytic infiltration was associated with the presence of eosinophils (p less than 0.05) and the total absence of NK cells was observed. No B lymphocytes were detected, apart from a few rare lymphoid follicles.

Administration, Intravesical↗
PubMed1988

Activation and infection of B cells by Epstein-Barr virus. Role of calcium mobilization and of protein kinase C translocation.

Both the activation and the transformation of human B cells by EBV were inhibited by either the Ca2+ channel blocking agent verapamil or the combination of theophylline and dibutyryl cAMP: the day 4 and day 20 peaks of [3H]TdR incorporation were abolished; the EBNA marker was not expressed by day 10; lymphoblastoid cell lines did not arise. Short term incubation of B cells with EBV or verapamil showed that the effect of verapamil was reversible and took place early in the interaction between EBV and B cells. The effect of EBV on the early metabolic events of B cell response was thus examined in the presence and in the absence of the drugs. Compared to anti-mu stimulation, supernatant of the transforming B95-8 strain as well as that of the non-transforming P3HR1 strain induced a drug sensitive increase of the free cytosolic Ca2+ concentration. This increase was associated with a protein kinase C translocation from the cytosol to a membrane bound compartment. Moreover, B95-8 supernatant induced phosphatidyl inositol metabolism by human B cells but at least four times less than that induced by anti-mu antibody. These metabolic events induced by EBV were significantly inhibited by anti-CD21 antibodies whereas anti-mu induced metabolic events were not. The infection of EBV negative Ramos cell line was prevented by verapamil or by theophylline + dibutyryl cAMP. Verapamil did not modify the density of EBV receptors but negatively interfered with the penetration of the virus into B cells. Thus B cell activation through the EBV receptor and virus penetration share a common metabolic pathway which is also used for transduction of the signal delivered through the membrane Ig.

Antibodies, Anti-Idiotypic↗
PubMed1985

Multifocal nonosteogenic fibroma: report of a case with ultrastructural findings.

The case of a patient in whom multiple nonosteogenic fibromas developed is reported. This condition is very unusual and must be differentiated not only from the multiple lesions that occur in association with well-known entities but also from some occasionally multifocal bone tumors. The lesion is characterized by proliferations of spindle cells disposed in storiform patterns, with numerous scattered multinucleated giant cells. Ultrastructural study revealed that the basic cell of this lesion had fine structural features of both fibroblast and myofibroblast cells.

Adolescent↗
PubMed1984

Mucin histochemistry of the columnar epithelium of the oesophagus (Barrett's oesophagus): a prospective biopsy study.

Columnar epithelium-lined oesophagus (CELO) is an acquired disorder associated with a high incidence of cancer. CELO consists of three histological types of epithelium: gastric-fundic, junctional, and specialised columnar, the last resembling intestinal metaplasia of the stomach. In a previous study of CELO an incompletely differentiated variant of intestinal metaplasia secreting sulphomucins (type II B) was found. This was shown to be associated with well differentiated adenocarcinoma, as in the stomach. The purpose of this paper has been to define by histochemistry the mucin profile of CELO in 17 patients and to compare it with the mucin profile of the gastroesophageal junction in 27 patients without CELO. In CELO a specialised columnar epithelium was always found and type II B intestinal metaplasia (with sulphomucins) showed the highest incidence (53%). In normal subjects, this type of intestinal metaplasia was found in only three of 27 cases. Type II B intestinal metaplasia has often been considered as a precancerous lesion or as an equivalent of dysplasia; consequently, its high incidence in our study on CELO raises the question of whether this lesion should be considered a high risk condition for adenocarcinoma of the lower oesophagus.

Barrett Esophagus↗
PubMed1983

[Amyloidosis and its bronchopulmonary localizations. Apropos of 3 cases].

Amyloidosis of the lower respiratory tract is a rare condition. We report three new cases and we review the literature. Tracheobronchial amyloidosis is the most frequent form. The diagnostic is made by fiberoscopy and biopsies with a risk of bleeding. Our patients were usually treated with intermittent bronchoscopic resections. In one of the three cases reported, desobstruction of the large airway was performed with laser. Nodular pulmonary amyloidosis is usually asymptomatic, and surgical resection results in cure in all cases. Diffuse pulmonary amyloidosis is very unusual and fatal.

Adult↗
PubMed1980

Bone remodeling in centrifuged rats: histomorphometric study after an 18-day run.

A histomorphometric and histodynamic study of bone tissue was conducted in rats exposed to 2 G centrifugation for a period of 18 d. Shortening of the femurs was observed, associated with alterations of the growth cartilage in centrifuged animals. The morphometric analysis demonstrates a reduction in bone volume without increase in the activity of osteoclasts. The fluorescent fixation during the dynamic study shows a reduced appositional rate. This result seems to reflect the numerous factors which contribute to the experimental centrifugation test: the osteoporosis is cortisone induced; it is a response to the aggression and probably conceals the remodeling due to higher stress loads.

Animals↗