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M Diab

Publications and source records attributed to M Diab.

At least 37 records · Page 2Linked to original sources
PubMed1995

Capsular polysaccharide types 5 and 8 of Staphylococcus aureus bind specifically to human epithelial (KB) cells, endothelial cells, and monocytes and induce release of cytokines.

In order to examine the possible implication of capsular polysaccharide (CP) types 5 and 8 (CP5 and CP8) from Staphylococcus aureus in the pathological mechanism associated with staphylococcal infections, we tested the immunomodulatory effects of CP5 and CP8 on human epithelial KB cells, endothelial cells, and monocytes. Using biotinylated CP5 and CP8, we provide evidence that both CPs bind to KB cells, endothelial cells, and monocytes in a dose- and calcium-dependent manner through specific interactions. These results were confirmed by competition experiments using soluble cell extracts. Furthermore, we show that CPs bind to identical cell membrane receptors on all three types of human cells and that human normal serum contains a factor(s) which inhibits the binding of both CPs to human KB cells, endothelial cells, and monocytes. The ability of CP5 and CP8 to stimulate the production of cytokines by the human cells was then examined. CP5 and CP8 trigger KB cells to produce interleukin-8 (IL-8); endothelial cells to produce IL-8 and IL-6; and monocytes to produce IL-8, IL-6, IL-1 beta, and tumor necrosis factor alpha. The release of cytokines by all three types of cells is time dependent and dose dependent, and the tumor necrosis factor alpha production by monocytes is not affected by the addition of polymyxin B. We further confirm that human normal serum inhibits the immunomodulatory effects of both polysaccharides on each kind of cell. These results confirm that S. aureus CPs act as bacterial adhesins having immunomodulatory effects for human cells.

Bacterial Adhesion↗
PubMed1995

Pulse oximetry.

Pulse oximetry is a reliable, noninvasive, easy to use means of continuously determining arterial oxygen saturation in virtually any setting. This article details the historical and technical development of this monitor; reviews the literature on application, accuracy, and response; and presents an overview of future advances.

Adult↗
PubMed1994

Abnormality of type IX collagen in a patient with diastrophic dysplasia.

There is growing evidence that a spectrum of chondrodysplasias are caused by mutations in the gene coding for type II collagen. The basic molecular defect in diastrophic dysplasia has not been defined, but it appears not to be in collagen type II. Cartilage contains other tissue-specific collagens, types IX, X, and XI, but no mutations have yet been found in their genes in clinical disease. Type IX collagen is hypothesized to play a role in the regulation of type II collagen fibril organization and structure in cartilage extracellular matrix. In this study, we have examined iliac crest growth cartilage from a patient with diastrophic dysplasia. Although collagen fibrils were markedly increased in diameter on transmission electron microscopy, type II collagen appeared to be normal biochemically. Type XI collagen was also normal. However, type IX collagen appeared abnormal on sodium dodecyl sulfate polyacrylamide gel electrophoresis with a pronounced excess of the COL1 domain of the molecule in pepsin extracts. The findings point to an abnormality in structure or metabolism of type IX collagen in diastrophic dysplasia.

Amino Acid Sequence↗
PubMed1993

The role of type IX collagen in osteoarthritis and rheumatoid arthritis.

Articular cartilage consists of a cellular and an extracellular compartment. The extracellular compartment is composed of collagen, proteoglycans, and noncollagenous matrix proteins. Collagen resists tensile forces and serves as an organizing skeleton that helps maintain the structural integrity of cartilage. Fourteen types of collagen have been identified. The cartilage-specific collagens are type II (the principal component), type IX, type X, and type XI. Type IX collagen is hypothesized to be the "glue" that holds together the type II collagen latticework of articular cartilage. Degradation of type IX collagen by proteolytic enzymes has been observed in the primary stages of osteoarthritis and rheumatoid arthritis. This degradation is thought to represent an "ungluing" of the collagen scaffold and has been proposed as the mechanism for the degenerative changes seen in osteoarthritic and rheumatoid cartilage.

Arthritis, Rheumatoid↗
PubMed1992

[Familial breast cancer in Arabs].

500 surviving Arab cancer patients in follow-up were interviewed with regard to other cases of cancer in their families. Among 73 who had breast cancer, in 15 (20.3%) there was another case of breast cancer among first-degree relatives. The incidence of both primary and familial breast cancer was higher among Christian than among Moslem women. We conclude that Arab women with breast cancer in their families are at high risk for developing breast cancer themselves.

Breast Neoplasms↗
PubMed1990

[Angioimmunoblastic lymphadenopathy and colonic lymphoma].

Angioimmunoblastic lymphadenopathy (AILD), first discovered in the 70's, is an infrequent disease which generally proves fatal within a short time. It is characterized by lymphadenopathies, hepatosplenomegaly, fever and rash. The most frequent laboratory findings are: anemia, leukocytosis with lymphopenia and non specific hypergammaglobulinemia. In spite of being considered a non malignant disease, it produces important immunity disorders which predispose the patient to serious infections, frequently fatal. In the course of time patients are likely to develop malignant lymphomas or other types of tumors. We describe a ganglionar proliferation and general symptoms in a patient who had been diagnosed as AILD by ganglionar biopsy. She was treated with corticosteroids during 8 months after which she had a complete recovery. Three months later the patient was readmitted with enterrorhagias and clear deterioration of her general condition. Tests showed the existence of a colon tumor and absence of adenomegaly in the areas previously affected by AILD. A colon surgery was carried out and a specimen examined. The anatomopathologic examination confirmed the existence of an immunoblastic lymphoma infiltrating the regional ganglionar area. Colon lymphomas constitute only 4% of all colon tumors; they are related to chronic gastrointestinal disease such as Crohn disease, ulcerative colitis, malabsorption syndromes, tumors and others. We conclude that in this patient AILD and prednisone administration constituted favoring factors for the development of an extranodal lymphoma.

Aged↗
PubMed1989

Modulation of cell-mediated immunity in mice with chronic unisexual or bisexual Schistosoma mansoni cercarial infection.

Three groups of C57BL/6J female mice were infected with female Schistosoma mansoni cercariae alone, male cercariae alone, or both sexes of cercariae. In a longitudinal study, the spleen cell proliferative responses to the mitogens phytohaemagglutinin (PHA) and Escherichia coli lipopolysaccharide (LPS) were monitored. Significant immune suppression was found in the three infected groups when compared with uninfected controls. Within the infected groups, mice inoculated with both sexes of cercariae were significantly more suppressed than those with single-sex cercarial infection. Thus, in addition to schistosome eggs, either sex of S. mansoni worms is capable, although to a lesser extent, of inducing hyporesponsiveness of cell-mediated immunity (CMI) in chronic schistosomiasis mansoni.

Animals↗
PubMed1989

Awareness following different techniques of general anaesthesia for caesarean section.

Using the isolated arm technique, the frequency of awareness was evaluated in 50 full-term patients undergoing elective Caesarean section under general anaesthesia. In 20 patients, anaesthesia was induced with thiopentone 4 mg kg-1, and in the other 30 patients, induction was with ketamine 1.5 mg kg-1. Following suxamethonium 1.5 mg kg-1 and tracheal intubation, anaesthesia was supplemented during the induction-delivery period in the thiopentone group with 50% nitrous oxide and 0.5% halothane in oxygen in 10 patients, and with 1% halothane in 100% oxygen in the other 10 patients. In the ketamine group, the patients underwent ventilation with 50% nitrous oxide and 0.5% halothane in oxygen in 10 patients, with 1% halothane in 100% in 10 patients, and with 100% oxygen only in the last 10 patients. Awareness was significantly greater after induction with thiopentone (14/20) than after ketamine (4/30). There were no significant differences in Apgar scores or umbilical vein blood-gas values in the newborns.

Anesthesia, General↗
PubMed1985

[Prognostic value of the exercise test performed less than 40 days after the first infarction].

Stress testing was performed in 159 men (mean age 49.83 years) between the 10th and 40th day after primary myocardial infarction. The average work achieved was 79 watts with a heart rate of 121/min, systolic blood pressure of 169 mmHg, and a double product of 20 544. The result was negative in 53 p. 100 of cases, and positive in 47 p. 100: the positive response was ischaemic in 23 p. 100 and non ischaemic in 24 p. 100 of cases. In the 2 years which followed, post-infarction angina was observed in 44 p. 100 of cases (14 p. 100 unstable angina), recurrent infarction in 7 p. 100 and death in 4 p. 100; coronary angiography was performed in 19 p. 100 of cases and coronary bypass surgery in 6 p. 100; 53 p. 100 of patients remained asymptomatic. The difference in predictive value between negative stress testing for an asymptomatic outcome and a positive ischaemic test for post-infarction angina and bypass surgery was important (p less than 0.001). The correlation was not as significant for death and recurrent infarction. The non-ischaemic positive result was of less value. There was no relationship to age but the prediction was more accurate in postero-inferior (p less than 0.001) than anterior infarction (p less than 0.05). The timing of the test affected the performance and patient comfort but had less influence on the results. Nevertheless, the predictive values were less good at 2 weeks than later on and significantly improved when testing was performed between the 10th and 11th week. However, early stress testing was valuable for identifying high risk subgroups.

Adult↗
PubMed1979

Autoradiographic study of distribution patterns of metals which occur as corrosion products from dental restorations.

Radioactive chromium, cobalt, gold and mercury, all of which may occur as corrosion products from dental restorations, were injected in single doses via the tail vein of mice and an in vivo analysis of their distribution was performed using whole-body autoradiography. Gold seemed to be inert and went mainly to the liver and bones. The other elements studied were distributed widely in the body and remained for a long period of time in specific target organs and tissues.

Animals↗
PubMed1966

[Audio-analgesia].

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Audioanalgesia↗