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J F Colombel

Publications and source records attributed to J F Colombel.

At least 253 records · Page 14Linked to original sources
PubMed1988

Eosinophilic gastroenteritis: ultrastructural evidence for a selective release of eosinophil major basic protein.

Ultrastructural study of mucosal eosinophils in a case of eosinophilic gastroenteritis involving stomach, duodenum and ileum showed an altered structure in ulcerated duodenal areas. The electron core density of eosinophil granules was inverted or disappeared and tubulovesicular structures occurred. Using immunogold staining with specific antibodies, major basic protein was detected diffusely in the matrix of eosinophil granules and out of the granules in tight association with extragranular membrane formations. In contrast, eosinophil cationic protein and eosinophil peroxidase were normally distributed in the granule matrix. When compared with the eosinophils in macroscopically normal duodenal mucosa in the same patient, these changes support a role for major basic protein in tissue damage in eosinophilic gastroenteritis. The diffusion of one granule protein from the granules to the exterior of the cells favours the view of a selective release of eosinophil mediators.

Adult↗
PubMed1988

Qualitative study of fecal alpha 1-proteinase inhibitor in normal subjects and patients with Crohn's disease.

We applied sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting to analyze fecal alpha 1-proteinase inhibitor (alpha 1 PI) from healthy subjects and patients with Crohn's disease. A component with Mr 38,000 was characterized in normal fecal extracts as well as in six pathological samples. In these cases, the Crohn's disease activity index (CDAI), a clinical index of severity of the disease, was 170 (SEM 47). In contrast, alpha 1 PI of Mr 51,000 was detected in fecal extracts from eight patients with active Crohn's disease (CDAI = 287, SEM 39). We conclude that fecal alpha 1 PI can be considered a marker of intestinal disease activity.

Adolescent↗
PubMed1986

Latent pulmonary involvement in Crohn's disease: biological, functional, bronchoalveolar lavage and scintigraphic studies.

We have investigated the following pulmonary related parameters in 22 patients with Crohn's disease who were free of clinical pulmonary symptoms and had normal chest roentgenograms and in 25 controls: serum angiotensin converting enzyme, pulmonary function tests, bronchoalveolar lavage (lymphocyte count and subpopulations, macrophage viability and superoxide anion release by macrophages) and pulmonary scannings. Serum angiotensin converting enzyme was lower in Crohn's disease (14.1 +/- 5.1) than in controls (25.2 +/- 4.7) (p less than 0.001). Twelve of 22 Crohn's disease (54%) had a bronchoalveolar lavage lymphocytosis (greater than 18% alveolar lymphocytes). Bronchoalveolar lavage lymphocytes subpopulations were quite variable. Twelve of 17 Crohn's disease (71%) had an increase spontaneous and/or stimulated superoxide anion production by alveolar macrophages. Six of 12 Crohn's disease (50%) had an increase physiologic dead space in the upper part of their lung against one of 11 controls (9%). These data suggest that most patients with Crohn's disease have a latent pulmonary involvement.

Adolescent↗
PubMed1986

[Role of the digestive tract immune system in the control of bacterial translocation in gnotoxenic mice].

The aim of this work was to study the role of gut associated lymphoid tissue in the control of bacterial translocation. Two strains of Escherichia coli were orally inoculated to 71 axenic mice. Ten days after, the 2 initial strains and 2 others, resulting from plasmidic exchanges, were present in the digestive tract of the mice which were divided in two groups: the first group (n = 41) received one intraperitoneal injection of cyclophosphamide 100 mg/kg; the second control group (n = 30) received isotonic saline. The following parameters were studied 3, 5 and 9 days after the injection: the population level of the 4 strains in the caecum, their translocation to mesenteric lymph nodes, liver, spleen and circulating blood, the density per unit surface of lamina propria plasma cells and intraepithelial lymphocytes in duodenal and caecal mucosae. The population in each strain found in the caecum was different from the 3 others but similar within the two groups of animals and remained unchanged with time. In the control group, bacterial translocation to the mesenteric lymph nodes decreased (p less than 0.01), while the density of plasma cells increased (p less than 0.01) from the 3rd to the 9th days. In the cyclophosphamide treated group, translocation to the mesenteric lymph nodes increased (p less than 0.01), while the density of intestinal plasma cells decreased (p less than 0.05) from the 3rd to the 9th days. Density of intraepithelial lymphocytes did not vary with time in each group and from one group to another. Bacterial translocation to liver, spleen and systemic blood was weak and did not increase in the treated group.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1985

Evidence of lymphocyte alveolitis in Crohn's disease.

Cellular characteristics of bronchoalveolar lavage (BAL) were investigated in 18 consecutive patients with Crohn's disease, who were free of clinical pulmonary symptoms and had normal findings on chest roentgenograms. Total BAL cell count and cellular viability of alveolar macrophages did not differ significantly between patients and control subjects. Percentage of alveolar lymphocytes was increased in 11 of 18 patients (from 18 percent to 79 percent). There was no apparent correlation between BAL differential cell count and abnormal pulmonary function tests noted in 11 patients, drug treatment or Crohn's disease site, and activity. These results demonstrate a high proportion of latent lymphocyte alveolitis as assessed by BAL, suggesting a latent involvement of the lung in Crohn's disease.

Adolescent↗
PubMed1984

[Gastric metastasis of a malignant melanoma of the choroid].

Gastric metastases of choroid malignant melanoma seem to be exceptional since less than 10 cases have been previously published. We report the case of a 71 year old patient with a gastric melanosarcoma secondary to a choroid malignant melanoma. Gastric metastasis was revealed by digestive bleeding occurring 18 years after right eye enucleation. Gastroscopy showed black ulcerated tumors. Histology confirmed the diagnosis portraying typical melanic pigments within the gastric mucosa. Laser photocoagulation of the gastric lesion was used for the first time in this indication. As a result, hemorrhage decreased and the patient's comfort was improved.

Aged↗
PubMedDate not supplied

[Digestive manifestations of food hypersensitivity in adults].

Food allergy, synonymous with food hypersensitivity (FHS), is defined as an immunologically-mediated adverse reaction to food. Initiation of FHS could result from a break in the immune mucosal barrier with abrogation of oral tolerance. Food hypersensitivity is mostly due to immediate-type reaction involving IgE-dependent mastocytes activation. Changes in intestinal function and structure have been mainly studies in an animal model of rat sensitized to egg albumin. Intraluminal antigen challenge resulted in abnormalities of gut absorption, secretion and motility in sensitized rats. In man, experimental data are scarce. Gastrointestinal manifestations of immediate FHS are varying and unspecific. A role for FHS in irritable bowel syndrome is debated. Participation of delayed-type FHS to digestive diseases is still questionable, but eosinophilic gastroenteritis might be an example. In clinical practice, diagnosis of FHS demands rigorous criteria. Double blind placebo-controlled food challenge has eventually proved to be the "gold standard" test for FHS diagnosis.

Animals↗