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B Gosselin

Publications and source records attributed to B Gosselin.

At least 91 records · Page 5Linked to original sources
PubMed1995

Secretion and mRNA expression of TNF alpha and IL-6 in the lungs of pneumoconiosis patients.

Exposure to coal-mine dust leads to coal workers' pneumoconiosis (CWP), characterized by the development of a perifocal and progressive fibrotic reaction. In order to confirm their in vivo participation in the pathogenesis of CWP, the expression of tumor necrosis factor (TNF) and interleukin-6 (IL-6) was evaluated in bronchoalveolar lavage (BAL) specimens collected from 12 patients with simple pneumoconiosis (SP) and six with progressive massive fibrosis (PMF), and in pulmonary tissue from one patient with SP and three with PMF. Expression of TNF and IL-6 was assessed using both in situ hybridization and immunohistochemistry. The number of positive cells found in BALF was significantly higher for patients with PMF (TNF = 55 +/- 6%; IL-6 = 46 +/- 12.8%) than for those with SP (TNF = 34 +/- 11.6%; IL-6 = 26 +/- 10.2%) or normal controls (TNF = 15 +/- 5.5%; IL-6 = 13.3 +/- 6%), and was correlated with cytokine concentrations in supernatants from alveolar macrophages (AM). In lung biopsies, the expression of messenger ribonucleic acid (mRNA) for TNF was associated with the presence of coal dust and was limited to lung macrophages; mRNA for IL-6 was detected in mononuclear phagocytes but also in other types of cells such as endothelial cells. Monokine synthesis was confirmed by immunohistochemistry. These data confirm that TNF and IL-6 production is increased in the lungs of pneumoconiotic patients. Moreover TNF and IL-6 expression was associated with the presence of coalmine dust particles, suggesting a direct role of mineral particles in the cytokine production and development of pneumoconiotic lesions in CWP.

Adult↗
PubMed1995

Expression of human mucous proteinase inhibitor in respiratory tract: a study by in situ hybridization.

Human mucous proteinase inhibitor (MPI) is present in bronchial secretions, where it participates in the protection of lung structures against degradation by leukocyte elastase. The protein has been localized by immunohistochemical studies and immunogold labeling essentially in the serous cells of the submucosal glands and also in the surface epithelial cells of central and peripheral airways. However, until now no gene expression study has been performed at the tissue level. In this study, in situ hybridization was used to precisely study MPI mRNA expression in bronchial tissue sections with a specific radiolabeled oligonucleotide probe. By light microscopy, MPI gene expression was localized exclusively in the serous and seromucinous acini of the submucosal glands of large airways. The MPI gene was expressed in submucosal glands of normal and carcinomatous tissue sections, whereas it was not expressed in bronchial and bronchiolar surface epithelia.

Base Sequence↗
PubMed1995

Clinical significance of p53 mutations in newly diagnosed Burkitt's lymphoma and acute lymphoblastic leukemia: a report of 48 cases.

PURPOSE: To correlate the presence of p53 mutations and initial characteristics, response to chemotherapy, and survival in newly diagnosed Burkitt's lymphoma (BL) and Burkitt's acute lymphoblastic leukemia (L3 ALL). PATIENTS AND METHODS: Forty-eight patients with newly diagnosed BL or L3 ALL, most of whom were treated with very intensive regimens, including early CNS disease treatment, were studied. Detection of p53 mutations was made by single-strand conformation polymorphism (SSCP) analysis of exons 5 to 8 of the gene, and mutations were determined by direct sequencing of exons with abnormal SSCP findings. Comparison of outcome between mutated and nonmutated cases was made in all patients and also after excluding five patients who received therapeutic regimens considered as suboptimal and one patient who died of AIDS while in complete remission (CR), as those six patients had no p53 mutations. RESULTS: A point mutation was found in nine patients (19%), and consisted of a missense mutation in seven and a chain-terminating mutation in two. SSCP, sequence, and cytogenetic analysis strongly suggested that eight of nine patients with mutations had retained the normal p53 allele, which had been lost in the remaining patient. These findings were confirmed by fluorescence-in-situ hybridization (FISH) with a p53-specific probe in two patients, including the one who had lost the normal p53 allele. Unexpectedly, mutations were significantly less frequent in patients with disseminated disease, ie, L3 ALL or stage IV BL (four of 35, 11%), than in more localized forms, ie, BL stage I, II, or III (five of 13, 38%) (P = .03). CR rates were similar in mutated (78%) and nonmutated cases (78%). The actuarial disease-free interval (DFI) after 12 months and actuarial survival rates after 24 months were 49% and 66%, respectively, in patients with mutations, and 73% and 48%, respectively, those without mutations. The differences were not significant. CONCLUSION: Our findings suggest that, contrary to what is seen in most other neoplasias, p53 mutations in newly diagnosed BL and L3 ALL are not associated with extensive tumor mass or poor response to intensive therapeutic regimens. It is hypothesized that this difference with most tumors could be due to the fact that p53 mutations in BL and L3 ALL are generally associated with persistence of a normal residual p53 allele, contrary to what is observed in the majority of tumors.

Actuarial Analysis↗
PubMed1995

[Erdheim-Chester disease. Clinico-pathologic study of two cases].

Erdheim-Chester disease is a rare visceral xanthogranulomatosis characterized by bilateral, symmetrical sclerosis of the metaphyseal regions of long bones and infiltration of foamy, lipid-laden histiocytes. Clinically, it ranges from an asymptomatic, focal process to a fatal, systemic disease. We report two new cases, different in their presentation and extension.

Female↗
PubMed1995

[Oxalosis].

Explore the source record for details and available documents.

Calcinosis↗
PubMed1995

[Acinar cell carcinoma of the pancreas revealed by Weber-Christian syndrome].

Acinar cell carcinoma of the pancreas is a rare tumor of the exocrine pancreas that may be associated with a characteristic syndrome of disseminated fat necrosis with a bad prognosis. We report a case of this tumor occurring in a 63 year-old man who presented with polyarthralgia and panniculitis of the legs. The histological features and the differential diagnosis of acinar cell carcinoma are discussed.

Carcinoma, Acinar Cell↗
PubMed1994

Pathology of Toxoplasma gondii infection in the nude rat. An experimental model of toxoplasmosis in the immunocompromised host?

Genetically athymic nu/nu (nude) rats, deficient in T cells, die from infection with various Toxoplasma gondii strains, including RH and Prugniaud strains. In contrast, these strains cause chronic infections without apparent symptoms in immunocompetent non-nude rats. We show here that nude rats die in two to three weeks after RH infection and three to four weeks after Prugniaud infection. Histological examination of brains from nude rats at different time points after infection, revealed an absence of lesions after RH strain infection and cysts with usually no inflammation after Prugniaud infection. Lungs from nude rats developed a fibrin alveolitis using either strain, whereas myocarditis with focal areas of necrosis were observed only after Prugniaud infection. Cysts and, in some cases, tachyzoites in the necrotic lesions were easily identifiable. The two strains of T. gondii elicited in nude rats a granulomatous hepatitis that only differed in intensity. Spleen and mesenteric lymph nodes appeared totally non reactive in both cases. This model allows immunological and parasitological studies by comparison with immunocompetent rat infection. Published data concerning toxoplasma pathology in AIDS, therefore, suggest that acute toxoplasma infection in nude rats may be a useful model for studying disseminated forms of toxoplasma infection found in AIDS patients.

Animals↗
PubMed1994

Evidence for eosinophil activation in eosinophilic cystitis.

Eosinophilic cystitis (EC) is a rare condition. Recent studies have shown that activated eosinophils release cytotoxic cationic proteins which can induce tissue damage. Moreover, in vitro studies have shown that interleukin-5 (IL-5) is a cytokine able to attract and activate eosinophils. The goal of this study was to detect a possible activation of eosinophils in EC using electron microscopy, in situ hybridization with an IL-5 RNA probe and immunochemistry with a specific anti-IL-5 antibody. Using these combined methods in a typical case of EC, we found numerous activated eosinophils synthesizing and secreting IL-5 protein. IL-5 could enhance the activation of eosinophils and their cytotoxic potential in bladder tissues. This mechanism might explain the chronicity of the lesions in EC.

Cystitis↗
PubMed1994

Airway-like inflammation of minor salivary gland in bronchial asthma.

T-lymphocytes are important components of the inflammatory cell infiltrate in bronchial mucosa in asthma. Because activated lymphocytes migrate through the thoracic duct and the general circulation to remote glandular and mucosal sites, we initiated this study to evaluate the histologic abnormalities of a minor salivary gland (MSG) associated with bronchial asthma. Fifty-eight asthmatic patients were prospectively studied (37 women, 21 men; mean age, 54 +/- 6 yr). Twenty-nine patients had allergic asthma (AA) and 29 had nonallergic asthma (NAA). Results were compared with those obtained from 15 healthy control subjects and 15 nonasthmatic patients with chronic obstructive pulmonary disease (COPD). MSG was normal in 14 of 15 patients with COPD and in 14 of 15 control subjects. Forty-three of 58 (74%) asthmatic patients presented MSG abnormalities. These were significantly more frequent in asthmatics (74%) than in patients with COPD and healthy control subjects (6%, p < 0.001 versus asthmatics) and in NAA (97%) than in AA (52%, p < 0.01). The main pathologic features of MSG in asthma were T-lymphocyte infiltration (57%: AA nine of 29; NAA 24 of 29), partly degranulated mast cells (64%: AA, 11 of 29; NAA, 26 of 29), basement membrane thickening (64%: AA, 11 of 29; NAA, 26 of 29), and endothelial cell changes (26%: AA, one of 29; NAA, 14 of 29). Eosinophils were found only in two cases. Expression of ICAM-1 was demonstrated in nine of 16 patients with NAA, whereas VCAM-1 and E-selectin were negative in all of them.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

[Extraosseous Ewing's sarcoma with thoracic localization].

We report two cases of extraosseous Ewing's sarcoma revealed by large volume thoracic tumour lesions, occurring in a clinical context of an alteration in general health. The tumour mass was occupying the upper half of the left hemithorax, and was invading the thoracic wall posteriorly in the first case; it occupied the whole of the right hemithorax with invasion of the first three ribs in the second case. The first patient received five treatments with chemotherapy, using cyclophosphamide in association with adriamycin, which led to a partial response and was completed with surgical excision and a further five doses of chemotherapy using cyclophosphamide in association with etoposide. Subsequently radiotherapy was given. There was an unfavorable outcome, with recurrence in the 13th month. The second patient received three courses of chemotherapy using cyclophosphamide in association with actinomycin D and vincristine, which allowed for an 80% reduction in the tumour volume. Surgical resection was then carried out, followed by five courses with the same chemotherapy protocol. Forty-two months after the diagnosis this patient remained in complete remission. These two cases enable us to stress the value of associating a chemotherapy protocol consisting of cyclophosphamide, actinomycin D and vincristine, with systemic surgical excision in tumours with a high potential for development.

Adult↗
PubMed1994

SCID-Hu mouse as a model for human lung HIV-1 infection.

HIV induces a multi-organ infection with a dual tropism for both lymphocytes and monocytes/macrophages. The lung is a target both for HIV infection and HIV-related opportunistic infections. The SCID mouse has provided the opportunity to develop a small animal model for HIV infection. However, HIV-1 infection of the human fetal thymus and liver (SCID Liv/Thy) implanted in these mice occurred only after direct intraimplant injection of HIV-1 and the resultant HIV-1 infection was restricted to the human thymus. Here we report that human foetal lung can develop in SCID Liv/Thy mice resulting in the development of normal human alveolar and bronchiolar lung compartments which can be productively infected with cell-free HIV-1 virus, leading to a systemic and bifocal infection. This SCID-Hu model should be useful for studying AIDS physiopathology, human viruses with lung tropism and for helping to define gene therapy protocols in lung human cells in vivo.

Acquired Immunodeficiency Syndrome↗
PubMed1994

[Familial thymoma and translocation t (14;20) (q24;p13)].

A familial lympho-epithelial thymoma with constitutional chromosomal translocation t (14;20) (q24;p13) is presented: the thymoma and its particular translocation are present in the mother and the two sons of her offspring. The small number of cases do not allow establishing any relation between thymoma and this particular translocation. Concerning genetic counseling, an annual thoracic radiography is necessary for all the other family members, carriers or not of the translocation.

Adult↗
PubMed1994

[Diffuse interstitial pneumonia revealing Erdheim-Chester's disease].

Erdheim-Chester's disease is a rare form of visceral xanthogranulomatosis. We report a case of a patient aged 50 presenting with a diffuse interstitial pneumonia which revealed Erdheim-Chester's disease with localisation in the bones, peri-aortic region and also with neurological involvement. The diffuse interstitial pneumonia which progressed chronically was characterised by a diffuse thickening of the septa with subpleural cysts and bilateral apical bullae with thickening of the pleura. Respiratory function tests showed a restrictive ventilatory defect with resting hypoxaemia which was aggravating by exercise. Broncho-alveolar lavage showed a lymphocytosis (26%) also with polymorpho neutrophils (11%). The pathological diagnosis was confirmed by transbronchial lung biopsy showing an excess of foamy histiocytes in the interstitium which are characteristic of the disease. The progress of this interstitial pneumonia is stabilised without immunosuppressive drugs.

Adrenal Cortex Hormones↗
PubMed1993

Conjunctival biopsy in scleroderma and primary Sjögren's syndrome.

Keratoconjunctivitis sicca complicates both scleroderma and Sjögren's syndrome. Scleroderma of recent onset is difficult to diagnose, but is easily recognized late in its course. To assess the value of the conjunctival biopsy in the diagnosis of scleroderma, we used light, scanning, and transmission electron microscopy to compare in a masked fashion specimens from 21 patients with scleroderma and 14 patients with primary Sjögren's syndrome. Epithelial changes permitted diagnosis of early scleroderma in the two groups of patients. Lymphocytic infiltrate was always present in Sjögren's syndrome, but not in scleroderma. Fibrosis was always found in scleroderma, even in scleroderma of recent onset, but was absent in Sjögren's syndrome. The fibrosis was distributed around capillaries in a band-like pattern and was associated with degranulating mast cells. Conjunctival biopsy is valuable for the early diagnosis of scleroderma and for differentiating between scleroderma and primary Sjögren's syndrome.

Adult↗