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Biomedical subjects

A Janin

Publications and source records attributed to A Janin.

At least 91 records · Page 5Linked to original sources
PubMed1997

Assessment of anti-endothelial cell antibodies in systemic sclerosis and Sjögren's syndrome.

OBJECTIVES: Anti-endothelial cell antibodies (AECA) have been detected in 19 to 30% of patients with systemic sclerosis (SSc). The objective of this study was first to assess the role of a secondary Sjögren's syndrome (SS) in the occurrence of AECA in SSc. Secondly, we researched AECA in patients with primary SS, and investigated whether AECA were associated with vascular manifestations (Raynaud's phenomenon and vasculitis). METHODS: IgG-AECA were tested by an ELISA method in serum samples from 50 patients with SSc (16 of them had also a secondary SS), 50 patients with primary SS, and 50 healthy controls. RESULTS: AECA levels were significantly higher in patients with SSc or primary SS than in healthy controls (p < 0.01 and p < 0.01, respectively). In patients with SSc, AECA values were significantly higher in patients with secondary SS (p < 10(-5)). In patients with primary SS, AECA levels were significantly higher in patients with Raynaud's phenomenon (p < 0.01), but not in patients with vasculitis. CONCLUSION: In patients with SSc, AECA are associated with a secondary SS. In patients with primary SS, AECA are associated with Raynaud's phenomenon, but not with vasculitis.

Adolescent↗
PubMed1997

[Amyloidosis AL of the breast in an ileal carcinoid tumor].

An ileal tumor was detected in a patient with monoclonal plasmocytosis of the bone marrow (IgA Kappa). The pathological examination showed a carcinoid tumor with amyloid stroma. Immunotyping of the amyloidosis showed that it was stained with the antibody directed against light chain kappa, though the amyloidosis was located within a carcinoid tumor.

Amyloidosis↗
PubMed1997

[Paraneoplastic pemphigus with tracheobronchial involvement].

BACKGROUND: Paraneoplastic pemphigus is a bullous skin disease with characteristic polymorphous clinical presentation and precise histological and immunological features. We report a case of paraneoplastic pemphigus associated with chronic lymphoid leukemia involving the tracheobronchial epithelium. CASE REPORT: A patient with chronic lymphoid leukemia developed pluriorificial lesions. There were several conjunctival, buccal and genital erosions associated with erosive plaques on the trunk, Nikolski's sign and bullous lesions suggestive of paraneoplastic pemphigus. Histology examination of a bulla showed intraepidermal blistering and suprabasal acantholysis. Direct immunofluorescence evidenced intercellular IgG and C3 deposits. Search for anti-intercellular substance antibodies was positive with fluorescence on specific paraneoplastic pemphigus substrates. At immunotransfer, the serum recognized several bands corresponding to 250, 230, 210 and 190 kD antigens, confirming the diagnosis of paraneoplastic pemphigus. Several days later, the patient's general condition deteriorated with bronchorrhea. Bronchial endoscopy visualized ulceronecrotic plaques. Tracheal biopsy evidenced acantholytic cells and intraepithelial cleavage. General corticosteroid therapy was initiated and led to improvement of the skin lesions but the patient died rapidly from pneumonia. Autopsy confirmed the presence of epithelial cleavage and acantholysis involving the trachea and bronchi. DISCUSSION: This case illustrates the difficulty of diagnosing paraneoplastic pemphigus in the early stages. The pluriorificial lesions were suggestive of a Stevens-Johnson syndrome. Besides the genital, conjunctival and buccal mucosa, other mucosa can be involved. In our case, despite the absence of an immunological element, histology was highly suggestive of specific tracheobronchial localizations. The presence of such lesions, which should be searched for in all cases with bronchopulmonary manifestations, worsens the prognosis.

Acantholysis↗
PubMed1996

Regulation of cathepsin D dependent on the phenotype of colon carcinoma cells.

We have studied the intracellular trafficking of cathepsin D in different colon carcinoma cell populations: the HT-29 cell line, composed of >95% undifferentiated cells; 2 subpopulations derived from this cell line, containing cells committed to differentiation into mucin-secreting cells (HT-29 MTX) or enterocyte-like cells (HT-29 G-) after confluence; and the Caco-2 cell line, which spontaneously differentiates into enterocyte-like cells after confluence. Post-confluent undifferentiated HT-29 cells and differentiated enterocyte-like HT-29 G- and Caco-2 cells secrete significant levels of cathepsin D in culture medium, in contrast to post-confluent differentiated mucin-secreting HT-29 MTX cells, which secrete this enzyme at a very low level. The intracellular content and the mRNA level of cathepsin D increase after confluence in the different cell types, particularly in Caco-2 cells, which intensify the secretion of cathepsin D along with the differentiation process post-confluence. Membrane-associated mature cathepsin D was detected in HT-29 cells but not in Caco-2 cells. In the different types of cell, pro-cathepsin D associates with the membrane concomitantly to its binding to an Mr 72,000 protein. Membrane association persists after dissociation of the complex in HT-29 cells but not in Caco-2 cells. In the mucin-secreting HT-29 MTX cells, cathepsin D was immunolocalised to the membrane of mucin vacuoles localised under the brush border. Our results show that cathepsin D can be regulated differently in colon carcinoma cells, and this finding might have specific functional implications for each cell type.

Cathepsin D↗
PubMed1996

IgE autoantibodies directed against the major bullous pemphigoid antigen in patients with a severe form of pemphigoid.

Bullous pemphigoid (BP) is an autoimmune subepidermal blistering disease characterized in part by circulating and tissue-bound IgG autoantibodies directed against the basement membrane zone. In addition, most of the patients with BP have increased serum IgE levels which seem to be correlated with the disease activity, whereas the presence of circulating anti-basement membrane zone IgE Abs has been reported in some patients. To elucidate whether IgE-dependent mechanisms play a role in the physiopathology of BP, we looked for the presence of IgE Abs specifically directed against the major BP Ag (BPAg1) in sera of BP patients at the onset and after remission of the disease. A radioimmunoassay and a 55-kDa recombinant protein (rBP55) obtained from a cDNA sequence, encoding the C-terminal region of the BPAg1 and containing the BPAg1 immunodominant epitopes, were used. Anti-rBP55 IgE Abs were found in 12 of the 19 sera tested. When the patients were divided into two groups according to the disease severity, anti-rBP55 IgE Abs were found only in patients with a severe form of the disease. Cytophilic IgE was detected on approximately 20% of peripheral blood eosinophils purified from BP patients. Immunohistochemistry studies suggested that some of the IgE-bearing cells in the lesional skin of BP patients are eosinophils. Immunostaining experiments revealed the existence of FcepsilonRI on both peripheral blood and tissue eosinophils. Taken together, these results suggest that IgE-dependent mechanisms could participate in the constitution of the lesions in BP.

Antibody Specificity↗
PubMed1996

ESM-1 is a novel human endothelial cell-specific molecule expressed in lung and regulated by cytokines.

We here report the identification of a novel human endothelial cell-specific molecule (called ESM-1) cloned from a human umbilical vein endothelial cell (HUVEC) cDNA library. Constitutive ESM-1 gene expression (as demonstrated by Northern blot and reverse transcription-polymerase chain reaction analysis) was found in HUVECs but not in the other human cell lines tested. The cDNA sequence contains an open reading frame of 552 nucleotides and a 1398-nucleotide 3'-untranslated region including several domains involved in mRNA instability and five putative polyadenylation consensus sequences. The deduced 184-amino acid sequence defines a cysteine-rich protein with a functional NH2-terminal hydrophobic signal sequence. Searches in several data bases confirmed the unique identity of this sequence. A rabbit immune serum raised against the 14-kDa COOH-terminal peptide of ESM-1 immunoprecipitated a 20-kDa protein only in ESM-1-transfected COS cells. Immunoblotting and immunoprecipitation of HUVEC lysates revealed a specific 20-kDa band corresponding to ESM-1. In addition, constitutive ESM-1 gene expression was shown to be tissue-restricted to the human lung. Southern blot analysis suggests that a single gene encodes ESM-1. A time-dependent up-regulation of ESM-1 mRNA was seen after addition of tumor necrosis factor alpha (TNFalpha) or interleukin (IL)-1beta but not with IL-4 or interferon gamma (IFNgamma) alone. In addition, when IFNgamma was combined with TNFalpha, IFNgamma inhibited the TNFalpha-induced increase of ESM-1 mRNA level. These data suggest that ESM-1 may have potent implications in the areas of vascular cell biology and human lung physiology.

Amino Acid Sequence↗
PubMed1996

Early expression of E-selectin, tumor necrosis factor alpha, and mast cell infiltration in the salivary glands of patients with systemic sclerosis.

OBJECTIVE: To assess the predictive value of early endothelial E-selectin and tumor necrosis factor alpha (TNF alpha) expression, as well as mast cell infiltration, in the subsequent progression to systemic sclerosis (SSc) in patients with Raynaud's phenomenon (RP) and abnormal nailfold capillaroscopic findings. METHODS: Clinical criteria were evaluated, and immunostaining was performed on lip biopsy samples from 22 patients with RP and abnormal capillaroscopic results. None of these patients initially fulfilled the American College of Rheumatology criteria for SSc. RESULTS: E-selectin, TNF alpha, and mast cell infiltration were found in 9, 10, and 8 of 11 patients, respectively, whose disease progressed to SSc, and in 0, 2, and 1 of 11 patients, respectively, whose disease did not progress to SSc (P < 0.001, P < 0.01, and P < 0.01, respectively). CONCLUSION: E-selectin, TNF alpha, and mast cell infiltration are detectable in the very early stages of SSc, prior to the onset of skin changes.

Adult↗
PubMed1996

An in vivo model of allergic inflammation: pulmonary human cell infiltrate in allergen-challenged allergic Hu-SCID mice.

CB.17 severe combined immunodeficient (SCID) mice were used to establish a model of allergic pulmonary inflammation. SCID mice were intraperitoneally reconstituted with 10(7) peripheral blood mononuclear cells (PBMC) from patients sensitive to Dermatophagoides pteronyssinus (Dpt) and 2 weeks later were exposed to Dpt aerosols. After Dpt nebulization, SCID mice engrafted with PBMC from Dpt-sensitive patients developed a specific human IgE response as well as an intense pulmonary infiltrate of human cells. In contrast, SCID mice reconstituted with PBMC from patients allergic to grass pollen or from non-allergic donors failed to produce IgE or to exhibit a similar inflammatory response. The level of the IgE production was dependent on the IgE level of the allergic donor. In the lungs of the same allergic SCID mice, 2 months after Dpt inhalation, the cell infiltrate contained CD45+, CD45RO+, CD20+ and HLA-DR+ human cells. They were located in perivascular and peribronchial areas and disseminated in the mouse lung parenchyma. Moreover, mRNA IL-5+ cells and eosinophils were found in peribronchial infiltrates. The observations indicate that humanized allergic SCID mice may develop, after nebulization with the relevant allergen, immune reactions similar to those observed in man and suggest that SCID mice may represent a useful model to analyze the regulatory mechanisms of IgE-associated allergic diseases.

Administration, Inhalation↗
PubMed1996

[Sicca syndrome and hepatitis C virus infection: a Gougerot-Sjögren pseudo-syndrome?].

These last years, different virus have been incriminated in the etiopathogeny of the primary-Sjögren's syndrome and more particularly the hepatitis C virus. We have led a prospective study over 23 patients presenting a primary Sjögren's syndrome, searching for a sign of infection by the hepatitis C virus and over 23 patients presenting an active chronic hepatitis C virus searching for a Gougerot-Sjögren syndrome. The overcoming of the hepatitis C virus in the Sjögren group was 4.7% which was not significatively higher than in our sample of population. Parallelly, the search of the Sjögren's syndrome, in the hepatitis C virus group, found 4 patients (feminine, average age 48.5 years old) whose clinical board was compatible with this diagnostic. Antinuclear antibodies have not been found in any of the 23 patients. The lymphocytic typing of the infiltrate in the minor salivary glands biopsies showed a predominance of the CD8 lymphocytes in a proportion of 2/1, contrasting with what is observed in primary Sjögren's syndrome. We concluded that hepatitis C virus may be more associated with a chronic lymphocytic sialadenitis than an authentic primary Sjögren's syndrome.

Adult↗
PubMed1996

[Role of biopsy of the accessory salivary glands in Löfgren's syndrome and other forms of sarcoidosis].

The diagnosis of sarcoidosis requires histopathological analysis. Easy accessible site of biopsy is seldom. A systematic labial salivary gland biopsy was performed in 62 suspected sarcoidosis: 22 patients with Löfgren syndrome (group I), and 40 patients with systemic sarcoidosis (group II). Systematic bronchial biopsy was performed in eight patients of group I and ten patients of group II. If systematic biopsies were negative, direct biopsies were performed (lymph node, skin, kidney, liver). In group I, 8/22 labial salivary gland biopsies and 1/8 bronchial biopsies were positive; in group II, 17/40 labial salivary gland biopsies and 5/10 bronchial biopsies were positive. In the other patients, direct biopsies were positive: 27 lymph nodes, eight skin, eight hepatic, four kidney biopsies. In conclusion, labial salivary gland biopsy (even in the absence of sicca syndrome) is more reliable than systematic bronchial biopsies, particularly in Löfgren syndrome and may avoid in 30 to 50% of the cases more aggressive and dangerous biopsies such as liver, kidney or deep lymph nodes biopsies.

Adult↗
PubMed1996

Pseudomembranous conjunctivitis following bone marrow transplantation: immunopathological and ultrastructural study of one case.

Pseudomembranous conjunctivitis (PMC) is a rare ophthalmic lesion usually caused by infectious agents such as streptococcus, Klebsiella, Chlamydia, or adenovirus. It can also be associated with skin lesions of toxic epidermal necrolysis (TEN) and graft-versus-host-disease (GVHD). We report the pathological study of a patient with PMC and GVHD who had a conjunctival biopsy before death. This allowed us to differentiate this form of PMC from PMC of infectious origin, and to find within the epithelium characteristic features of acute GVHD and mononuclear cells expressing natural-killer markers. This suggests that this form of PMC resulted from a very acute, cytotoxic form of GVHD. Because PMC in bone marrow recipients can be related to infections, TEN, or acute GVHD, a systematic pathological study is required to guide the therapy.

Adult↗
PubMed1996

Aberrant expression of a human mucin gene (MUC5AC) in rectosigmoid villous adenoma.

BACKGROUND & AIMS: Rectosigmoid villous adenomas (RVAs) account for approximately 10% of all colorectal tumors. They have distinct pathological features, including abundant mucus secretion, possible malignant transformation, and multiple recurrences after conservative treatment. The aim of this study was to determine the nature of any changes in mucin gene expression in RVAs. METHODS: In situ hybridization was used to examine mucin messenger RNA expression in a series of 22 patients with an RVA. Five normal rectal and colonic mucosae and five rectal adenocarcinomas were used as controls. RESULTS: In the 22 RVAs, we found an overexpression of MUC2 and an aberrant expression of MUC5AC. This MUC5AC expression was more intense in RVAs with low-grade dysplasia than in those cases with high-grade dysplasia. Moreover, in 4 cases, it was detected at a distance from the tumor in areas previously considered as normal by endoscopic and histological examination. CONCLUSIONS: MUC5AC seems to be a specific marker for RVAs and thus may be useful for the early detection of RVA recurrences after endoscopic laser treatment.

Adenoma, Villous↗
PubMed1996

Interleukin 3, granulocyte-macrophage colony-stimulating factor, and interleukin 5 in eosinophilic gastroenteritis.

BACKGROUND & AIMS: Eosinophilic gastroenteritis (EG) is characterized by an eosinophilic infiltration of the gastrointestinal tract. The mechanism for the intestinal recruitment of eosinophils in EG remains unknown. Eosinophil recruitment and activation is induced by three main cytokines: interleukin (IL) 3, granulocyte-macrophage colony-stimulating factor (GM-CSF), and IL-5. The aim of this study was to examine the immunoreactivity for IL-3, GM-CSF, and IL-5 within the duodenal and colonic mucosa of 10 patients with EG. METHODS: Endoscopic biopsy specimens were obtained from 10 patients with EG and 10 controls. IL-3, GM-CSF, and IL-5 was evaluated by immunohistochemistry. Electron microscopy combined with immunogold staining was used to identify the labeled cells and to localize these growth factors ultrastructurally. RESULTS: A significant increase in the number of eosinophils was found in both duodenal and colonic mucosa from all 10 patients with EG compared with controls. In the same tissue, immunohistochemistry detected IL-3, GM-CSF, and IL-5 in 9 of 10 patients with EG. The one exception had received treatment with steroids. These cytokines were not detected in the control group. Ultrastructurally, IL-3, GM-CSF, and IL-5 were localized in the granule matrix of eosinophils. CONCLUSIONS: The release of these cytokines with autocrine and/or paracrine activities by eosinophils may be involved in the persistence of intestinal eosinophil infiltration.

Adolescent↗
PubMed1996

Linear and whorled nevoid hypermelanosis versus incontinentia pigmenti: is pigmentary incontinence really a distinctive feature?

This report describes a 3-year-old boy who presented with skin lesions characterized by multiple streaks of hyperpigmentation following Blaschko's lines since 6 weeks of age. The clinical features are consistent with the diagnosis of linear and whorled nevoid hypermelanosis (LWNH), but differ substantially from this entity by the pigmentary incontinence observed on both the paraffin and electron microscopy sections. Despite the presence of pigmentary incontinence, the diagnosis of incontinentia pigmenti (IP) can be ruled out on the basis that the patient is a male, with none of the characteristic anomalies present in this syndrome, and that he never presented with inflammatory or eruptive skin lesions. This observation suggests that pigmentary incontinence may not differentiate IP from LWNH as conclusively as previously reported in the literature.

Age of Onset↗
PubMed1996

Specific mucosal erosions in hypereosinophilic syndrome. Evidence for eosinophil protein deposition.

BACKGROUND: Mucosal erosions can be a presenting feature of the hypereosinophilic syndrome. The aim of this study was to analyze in situ the presence of eosinophil proteins and the state of eosinophil activation. Biopsy specimens of mucosal lesions and normal skin were taken from two men with oral and genital erosions typical of hypereosinophilic syndrome. Tissue sections were immunohistochemically labeled with anti-major basic protein, anti-eosinophil-derived neurotoxin, and anti-eosinophil peroxidase antibodies. The same specimens were also subjected to electron microscope examination. OBSERVATIONS: Eroded specimens displayed areas of eosinophil spongiosis within which extracellular deposits of eosinophil peroxidase, major basic protein, and eosinophil-derived neurotoxin were present. In normal skin, only a few eosinophils were present within the capillary lumen, and no extracellular deposits of these proteins were seen. Under the electron microscope, the cytoplasmic membranes of eosinophils located around the erosion were disrupted. Remnants of necrotic keratinocytes were found near these lysed eosinophils. CONCLUSION: As with other involved organs in hypereosinophilic syndrome, mucosal erosions seem to be the consequence of eosinophil protein release.

Humans↗
PubMed1996

Histochemical and ultrastructural study of diffuse melanoderma after bone marrow transplantation.

Hyperpigmentation is a well-recognized feature of cutaneous graft-versus-host disease (GVHD), and is usually restricted to sites where lichenoid or sclerodermiform lesions have occurred. Since 1975, two of 745 patients treated by allogeneic bone marrow transplantation in our institution have developed diffuse melanoderma which differed considerably from the classic presentations. They both developed acute GVHD, then lichen planus-like chronic lesions and diffuse melanoderma. Histology of biopsies of the pigmented skin showed intense pigment deposition in the basal and suprabasal layers, and in dermal macrophages. On split-dopa, melanocyte counts were 98 and 93 per field, respectively. Electron microscopy showed melanocytes protruding into the dermis, and dark melanosomes in all epidermal layers and in macrophages. These findings were suggestive of post-inflammatory hyperpigmentation. In bone marrow recipients, de novo melanoderma is a rare event which could represent a feature of cutaneous GVHD in pigmented subjects.

Adolescent↗