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S Alsalameh

Publications and source records attributed to S Alsalameh.

At least 19 recordsLinked to original sources
PubMed2003

Review article: The pharmacological properties and clinical use of valdecoxib, a new cyclo-oxygenase-2-selective inhibitor.

Cyclo-oxygenase-2-selective inhibitors produce less gastric damage than conventional non-steroidal anti-inflammatory drugs. Valdecoxib is a new orally administered cyclo-oxygenase-2-selective inhibitor, recently approved for use in osteoarthritis, rheumatoid arthritis and primary dysmenorrhoea in the USA. The drug has been evaluated in more than 60 clinical studies involving more than 14 000 patients and healthy volunteers. The analgesic efficacy of valdecoxib at a dose of 10 mg once daily in both osteoarthritis and rheumatoid arthritis is superior to that of placebo and similar to that of traditional non-steroidal anti-inflammatory drugs. Valdecoxib is effective in single doses of up to 40 mg for the alleviation of acute menstrual pain and has a rapid onset of action (within 30 min) and a long duration of analgesia (up to 24 h). Valdecoxib is well tolerated and has safety advantages compared with traditional non-steroidal anti-inflammatory drugs in terms of less gastrointestinal toxicity and a lack of an effect on platelet function. The incidence of adverse effects involving the kidney (fluid retention, oedema and hypertension) is similar to that of non-selective, non-steroidal anti-inflammatory drugs.

Adult↗
PubMed2000

Rectal stricture associated with the long-term use of ibuprofen suppositories.

Here, we report the case of a 64-year-old woman who suffered from chronic lower backache for which she received ibuprofen suppositories. The patient was admitted to the hospital with a suspected rectal tumor. Clinical examination did not reveal any abnormal finding apart from a mild, bilateral peritibial edema. On rectal examination, an area of stenosis was detected approximately 7 cm above the anal verge. All laboratory parameters, including different tumor markers, were within normal range. Pelvic CT scan and colonoscopy revealed a circular rectal stenosis with severe destruction of the rectal mucosa. The rectal biopsy taken during endoscopy showed severe acute and chronic ulceration, chronic granulation and fibrosis with lymphocytic infiltration. After exclusion of sexually transmitted diseases such as syphilis and lymphogranuloma venerium or exposure to drugs as a possible cause of rectal stenosis, the history in this particular case suggests that the prolonged use of the cyclooxygenase (COX) inhibitor "ibuprofen" as a suppository is the cause of mucosal destruction and rectal stenosis.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1999

Distribution of TNF-alpha, TNF-R55 and TNF-R75 in the rheumatoid synovial membrane: TNF receptors are localized preferentially in the lining layer; TNF-alpha is distributed mainly in the vicinity of TNF receptors in the deeper layers.

The expression of TNF-alpha and its receptors in the rheumatoid synovial membrane was investigated using immunohistochemistry and immunocytofluorescence. TNF-alpha+ cells (< 10% of all cells) were found in all regions, predominantly in sublining and diffuse infiltrates. The highest percentage of TNF-R+ cells was found in the lining layer (50-90%), with a slight predominance of TNF-R55. In the sublining, fewer cells expressed TNF-R (approximately 50%), mostly TNF-R75. TNF-R75+ cells were also detectable in diffuse infiltrates and lymphoid aggregates (10-50%). These contained only individual TNF-R55+ cells. In diffuse infiltrates, there were slightly more TNF-R55+ cells than in lymphoid aggregates (in both cases < 10%). In sequential sections, TNF-alpha+ cells localized mostly in the vicinity of TNF-R+ cells. Macrophage-like cells appeared to be the predominant TNF-R+ cell type. CD3+ T cells in lymphoid aggregates expressed exclusively TNF-R75. Subsequently, the expression of membrane-bound TNF-alpha, TNF-R55 and TNF-R75 was tested by FACS analysis in isolated RA synoviocytes (n = 7 patients). Only four specimens expressed mTNF-alpha, and that on a low percentage of cells (2 +/- 2.4%; mean +/- SD). In contrast, all specimens expressed higher percentages of TNF-R55 and TNF-R75 (21 +/- 1% and 14 +/- 7.1%, respectively). These results demonstrate that: (1) the percentage of cells expressing soluble/transmembrane TNF-alpha is greatly outnumbered by the percentage of cells expressing TNF receptors; and (2) TNF-alpha-expressing cells are localized in regions expressing substantial levels of TNF receptors. Therefore, the known pro-inflammatory and pro-arthritic effects of TNF-alpha are probably mediated by local interactions between the receptors and their soluble and transmembrane ligands.

Adult↗
PubMed1999

Preferential expression of tumor necrosis factor receptor 55 (TNF-R55) on human articular chondrocytes: selective transcriptional upregulation of TNF-R75 by proinflammatory cytokines interleukin 1beta, tumor necrosis factor-alpha, and basis fibroblast growth factor.

OBJECTIVE: Articular cartilage is the main target for tumor necrosis factor-alpha (TNF-alpha) and interleukin 1(IL-1) actions. These cytokines are believed to mediate cartilage degradation in arthritis. We studied the expression of TNF receptors (TNF-R) on human articular chondrocytes and their regulation by IL-1beta, TNF-alpha, and basic fibroblast growth factor (bFGF). METHODS: The expression of TNF-R55 and TNF-R75 on human nonarthritic articular chondrocytes was analyzed on protein and mRNA levels by ligand binding studies and reverse transcription polymerase chain reaction (RT-PCR) technique. The regulation of these receptors induced by IL-1 TNF-alpha, and bFGF on mRNA level was studied using RT-PCR. RESULTS: Both TNF-R55 and TNF-R75 are expressed constitutively on human articular chondrocytes, and the number of both receptors varied between 822 and 3880 receptors per cell, depending on the donor cartilage used. Using TNF receptor-specific antibodies, we show that normal chondrocytes express mainly TNF-R55. These results are consistent with the mRNA data obtained by RT-PCR. mRNA expression of TNF receptors is regulated by IL-1beta, TNF-alpha, and bFGF. On human chondrocytes the expression of TNF-R75 mRNA was markedly upregulated by IL-ID, TNF-alpha, and bFGF, whereas the expression of TNF-R55 mRNA remained largely unchanged. A combination of IL-1beta and TNF-alpha, but not of IL-1beta and bFGF, showed an additive effect on TNF-R75 mRNA expression. CONCLUSION: The expression of TNF-R55 and TNF-R75 on human articular chondrocytes is modulated independently by IL-1beta, TNF-alpha, and bFGF, suggesting a role of these regulatory mechanisms in the degradation processes of human articular cartilage in inflammatory joint diseases.

Antigens, CD↗
PubMed1997

Pannocytes: distinctive cells found in rheumatoid arthritis articular cartilage erosions.

A distinctive cell was identified from sites of rheumatoid arthritis cartilage injury. Similar cells are not found in lesions of osteoarthritis cartilage. We have designated them as pannocytes (PCs). Their rhomboid morphology differs from the bipolar shape of fibroblast-like synoviocytes or the spherical configuration of primary human articular chondrocytes. Chondrocytes are short-lived, whereas the original PC line grew for 25 passages before becoming senescent. Features in common with cultured primary chondrocytes include maximal proliferation in response to transforming growth factor-beta a catabolic response to interleukin-1 beta, collagenase production, and mRNA for the induced lymphocyte antigen and inducible nitric oxide synthase. Despite the presence of the inducible nitric oxide synthase message, PCs do not produce NO either constitutively or when cytokine stimulated. Each of the mesenchymal cells, fibroblast-like synoviocytes, primary chondrocytes, and PCs have the gene for type I collagen, but the type II collagen gene is detected only in primary chondrocytes. PCs can be distinguished from fibroblast-like synoviocytes and primary chondrocytes by their morphology, bright VCAM-1 staining, and growth response to cytokines and growth factors. Their prolonged life span in vitro suggests that PCs might represent an earlier stage of mesenchymal cell differentiation, and they could have a heretofore unrecognized role in rheumatoid arthritis joint destruction.

Antigens, Surface↗
PubMed1995

Therapy with OKT3 monoclonal antibody in refractory T cell acute lymphoblastic leukemia induces interleukin-2 responsiveness.

Administration of cytokines to patients with leukemia or lymphoma may recruit dormant malignant cells into cell cycle and thus make them more susceptible to chemotherapy. We treated a patient with refractory T cell acute lymphoblastic leukemia (ALL) with OKT3 monoclonal antibody and observed a dramatic but transient decrease of lymphoblasts. The T ALL cells were rather mature by morphology and immunophenotyping, expressing CD7, CD4, CD8 and CD3 surface antigens and nuclear TdT. Cytogenetic analysis revealed inversion of chromosome 14(q11q32.1). A total of 500 mg OKT3 (maximum dose 50 mg/day) was given. A decrease of lymphoblasts in the blood and a reduction of spleen size was observed. Complement levels dropped remarkably. Despite increasing serum levels of tumor necrosis factor, treatment was well tolerated overall. CD3 therapy induced strong IL-2 responsiveness of the lymphoblasts. Thus, OKT3 antibody treatment not only significantly decreased CD3-positive tumor cells, but also induced IL-2-mediated proliferation. This may also allow sequential application of CD3 and IL-2 to render certain T cell tumors more susceptible to chemotherapy.

Adult↗
PubMed1994

Humoral immune response against minor collagens type IX and XI in patients with cartilage graft resorption after reconstructive surgery.

OBJECTIVES: The humoral immune response against a broad spectrum of cartilage antigens (cellular and matrix antigens) was studied in a group of patients who showed resorption and/or rejection of transplanted cartilage in nasal surgery. METHODS: Sera were obtained from patients with successful and unsuccessful cartilage grafting in the nose, from age and sex-matched healthy donors and from patients with rheumatoid arthritis. Antibodies to cartilage components were analysed by the following methods: (1) indirect immunofluorescence on cartilage sections, (2) ELISA using cultured human chondrocytes, isolated chondrocyte membranes and purified collagens type I, II, III, VI, IX and XI, and (3) immunoblotting with purified collagens and chondrocyte cell membranes. RESULTS: In the cartilage grafting group showing resorption problems, levels of anti-collagen antibodies were significantly higher against native collagen types IX (p < 0.002) and XI (p < 0.002) compared with the non-resorption group and the normal donors. Both transplantation groups revealed elevated reactivities against isolated chondrocytes in the ELISA. In contrast, no reactivity was detectable against collagens type II, III, and VI and chondrocyte cell membranes by both ELISA and immunoblotting. CONCLUSIONS: These data demonstrate for the first time the existence of a humoral immune response, primarily directed against the so called 'minor cartilage collagens', in patients showing cartilage resorption. Autoreactivities to collagen which are typical of inflammatory rheumatic diseases may also play an important role in the repeated failure of cartilage grafting.

Adult↗
PubMed1994

Antigen presenting cell function of class II positive human nasal chondrocytes.

It is postulated that class II positive chondrocytes may be actively involved in the destruction or rejection of vital transplanted cartilage grafts. To investigate whether human nasal chondrocytes may also function as accessory cells in ongoing immune reactions with cartilage destruction, mixed leukocyte-chondrocyte cultures and antigen presentation assays were performed. Freshly isolated HLA class II antigen negative chondrocytes obtained from nasal septa were not stimulatory to autologous resting T lymphocytes. HLA class II positive chondrocytes treated with gamma-interferon were able to present antigens to autologous activated T cells derived from an antigen (tetanus) specific T cell line. Upon incubation with activated T cells, initially class II negative changed their phenotype resulting in the expression of class II antigens and enabling them to effectively present antigen. These results suggest an active role of chondrocytes in the rejection of cartilage grafts.

Antigen-Presenting Cells↗
PubMed1994

Basic mechanisms in rheumatoid arthritis: the role of T lymphocytes in rheumatoid synovitis.

Undoubtedly, synovitis is a cell-mediated process involving various cell types, such as T cells, B cells, APC, monocytes/macrophages, synoviocytes, chondrocytes, and cytokines. Therefore, it is difficult to clarify the cell type that plays the central role in the inflammatory process. Despite this difficulty, there is strong evidence that T cells mediate the disease in collaboration with APC that bear specific antigenic peptides. The mediators released could perpetuate an ongoing inflammatory process in the joints irrespective of the nature of the initiating agents. Therefore, many approaches to a more specific immunotherapy for RA have been developed, directed toward the modulation of T cell function. Thus far, various forms of chemical and biologic treatment have been used, such as cyclosporin A and monoclonal antibodies directed against T-cell epitopes and IL-2 receptor, with some beneficial effects on the course of RA. The development of a more specific immunotherapy using reagents directed against the T-cell receptor and vaccination with specific T cells await further studies, since we still do not know the inciting antigen(s) in RA. Nevertheless, we are hopeful that the ongoing search for the still unknown antigen(s) will be successful, thus providing new and better treatment regimens for a still uncurable disease.

Animals↗
PubMed1994

Regulation of granulocyte macrophage colony stimulating factor production by human articular chondrocytes. Induction by both tumor necrosis factor-alpha and interleukin 1, downregulation by transforming growth factor beta and upregulation by fibroblast growth factor.

OBJECTIVE: To study the regulation of granulocyte macrophage colony stimulating factor (GM-CSF) production by human articular chondrocytes which may contribute to the local GM-CSF production encountered in rheumatoid joints. This growth factor induces human macrophages to migrate and proliferate, improves their accessory function and increases the expression of HLA-DR antigens on macrophages and macrophage-like synoviocytes. METHODS: GM-CSF was assayed by ELISA and a bioassay in cell and organ culture supernatants from human articular chondrocytes, by in situ hybridization, Northern blot analysis and affinity chromatography. RESULTS: Both interleukin 1 (IL-1) and tumor necrosis factor-alpha (TNF-alpha) synergistically or additively stimulated chondrocytes to produce significant amounts of immunoreactive and bioactive GM-CSF with maximum values of 2928 pg/ml (p < 0.0001 both for IL-1 and/or TNF-alpha vs baseline). Affinity chromatography using specific monoclonal antibodies for human GM-CSF resulted in the purification of a chondrocyte derived 22-23 kDa protein. In situ hybridization demonstrated that the number of chondrocytes that expressed GM-CSF mRNA correlated well to the amount of GM-CSF secreted into the cultures. Transforming growth factor beta (TGF-beta) and to a lesser extent interferon-gamma (IFN-gamma) were able to decrease GM-CSF production induced by IL-1 and/or TNF-alpha. In contrast, basic fibroblast growth factor (FGF) in combination with IL-1 strongly increased GM-CSF secretion up to 8.5-fold. IFN-gamma, IL-6, TGF-beta, bFGF and IL-8 given alone failed to induce chondrocytes to produce GM-CSF. Steroids and low concentrations of cyclooxygenase inhibitors in general suppressed cytokine induced GM-CSF production. CONCLUSION: Our data demonstrate that both proinflammatory cytokines IL-1 and TNF-alpha induce an immunoreactive and biologically active GM-CSF by human articular chondrocytes that appears to be downregulated by TGF-beta and upregulated by FGF. GM-CSF produced locally by cartilage cells may be an important cytokine involved in the activation and proliferation of pannus cells, that can be modulated by interactions with cytokines present in the inflamed joints, thus possibly contributing to the chronic infiltration and destruction of cartilage in inflammatory joint diseases.

Cartilage, Articular↗
PubMed1994

Antibodies to the minor cartilage collagen type IX in otosclerosis.

The presence of antibodies to collagens type I, II, III, VI, IX, and XI was studied in patients with otosclerosis, using enzyme-linked immunosorbent assays. Levels of antibodies to collagens type II and IX were significantly higher in these patients as compared to sex- and age-matched control subjects, whereas no differences were found between the levels of antibodies to collagens type I, III, VI, and XI. These observations for the first time document the presence of autoantibodies against a minor collagen type IX in patients with otosclerosis and support a possible role for collagen autoimmunity in the etiology of otosclerosis.

Adult↗
PubMed1993

Preferential cellular and humoral immune reactivities to native and denatured collagen types IX and XI in a patient with fatal relapsing polychondritis.

We describe a patient with histologically confirmed relapsing polychondritis, an episodic systemic disorder. Although the etiology is unknown and its pathogenesis is incompletely understood, there is evidence strongly suggesting immunologically mediated mechanisms. Enzyme linked immunosorbent assays, immunoblotting and cellular immune responses using lymphocyte proliferation assays showed strong parallel humoral and cellular immune reactivities against collagens type IX and XI. There was also a considerable response to collagen type II which, however, was less pronounced compared to collagen type IX and was directed to native epitopes. Our findings demonstrate a highly distinct immune response to minor matrix collagens in a destructive cartilage disease and thus strongly argue against nonspecific anticollagen immune reactions simply representing epiphenomena resulting from cartilage damage.

Aged↗
PubMed1992

[Significance of immune reactions to cartilage tissue in use of cartilage transplants in nose surgery: detection of anti-collagen antibodies].

In a group of patients who showed repeated resorption or rejection of the transplanted cartilage graft, the immune response against a broad spectrum of collagen, namely, types I, II, VI, IX and XI, was investigated. We found a humoral immune reactivity against collagen type IX und XI, and to a lesser degree against collagen type I, demonstrating a specific immune response to these matrix collagens. These data suggest that some of the unsuccessful results obtained with cartilage grafts may be influenced by factors independent of the operative technique, such as immunological reactions.

Adult↗
PubMed1992

[Role of cytokines and growth factors in joint destruction processes].

Cytokines and growth factors are important mediators of inflammatory reactions and play a central role in the physiologic regulation of bone and cartilage cell activities and in joint destruction. The net effects of cytokines on target tissues depend on the relative pericellular concentrations of several cytokines and their inhibitors in the inflammatory tissue. It is possible to suppress the effects of cytokines with natural or synthetic inhibitory molecules. The measurement of cytokines and their inhibitors may be useful to understand the pathogenesis and to develop new therapies for inflammatory joint diseases. In this review the following cytokines will be reviewed: interleukin 1 and its inhibitor, tumor necrosis factor alpha and its inhibitor, interleukin 6, interferon gamma, transforming growth factor beta, colony-stimulating factors, fibroblast growth factors, platelet derived growth factor and prostaglandins.

Arthritis↗
PubMed1991

Antigenicity and accessory cell function of human articular chondrocytes.

It is postulated that chondrocytes may be actively involved in the pathogenesis of inflammatory joint diseases, presumably by providing tissue specific antigens that may initiate or sustain autoimmune reactions. To investigate whether chondrocytes may also function as accessory cells in ongoing immune processes, mixed leukocyte-chondrocyte cultures and antigen presentation assays were studied. Freshly isolated and short term cultured HLA class II antigen (Ia) negative as well as gamma-interferon treated Ia positive chondrocytes were weakly or not stimulatory to allogeneic or autologous resting lymphocytes derived from either normal donors or patients with rheumatoid arthritis. In an antigen presenting system using tetanus toxoid, the majority of chondrocyte preparations tested induced an antigen driven response in HLA matched allogeneic or autologous resting T cells which, however, was much less when compared to blood monocytes. In contrast, using activated T cells derived from tetanus toxoid specific T cell lines, an efficient antigen presenting capacity could be demonstrated in both Ia positive and initially Ia negative chondrocytes. Interestingly, the latter population had acquired Ia antigens upon incubation with the T cell line.

Antigen-Presenting Cells↗