Biomedical subjects

K Yildirim

Publications and source records attributed to K Yildirim.

7 recordsLinked to original sources

PubMed2004

The effect of individualized diet challenges consisting of allergenic foods on TNF-alpha and IL-1beta levels in patients with rheumatoid arthritis.

OBJECTIVE: To investigate the effect of individualized diet challenges consisting of allergenic foods, defined by the skin prick test (SPT), on tumour necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) levels in patients with rheumatoid arthritis (RA). METHODS: Twenty patients with a positive SPT response for food extracts and 20 with a negative SPT response were enrolled. None of the patients had active disease. All patients were fasted for the most common allergenic foods for 12 days and then allocated to two groups according to SPT results. Food challenges were performed with allergenic foods in the prick-positive group (PPG) and with corn and rice in the prick-negative group (PNG) for a period of 12 days. Then, allergenic foods were excluded from the PPG patients' diet and corn and rice were removed from the PNG patients' diet. Clinical examinations were performed after fasting (baseline), at the end of the challenge phase and at the end of the re-elimination phase. Stiffness, pain, tender and swollen joint counts, health assessment questionnaire (HAQ), Ritchie's articular index, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and serum TNF-alpha and IL-1beta levels were measured. RESULTS: TNF-alpha (P < 0.01), IL-1beta (P < 0.05), ESR (P < 0.05) and CRP (P = 0.001) levels and all of the clinical variables, except HAQ, were increased with food challenges in the PPG. These increases were also recorded after the re-elimination phase. In the PNG, no significant change was seen in any of the variables, except pain (P < 0.05). During the study, important differences were observed for most of the variables between the two groups. Thirteen (72%) patients in the PPG and three (18%) in the PNG experienced disease exacerbation with challenges. This aggravation continued after elimination. CONCLUSIONS: Our results suggest that individualized dietary revisions may regulate TNF-alpha and IL-1beta levels in selected patients with RA.

Adult↗

PubMed2004

Correlation between soluble intercellular adhesion molecule 1 level and extracellular superoxide dismutase activity in rheumatoid arthritis: a possible association with disease activity.

OBJECTIVE: We investigated serum levels of soluble intercellular adhesion molecule-1 (sICAM-1) and the activity of extracellular superoxide dismutase (EC-SOD) in rheumatoid arthritis (RA). We also considered whether there was a correlation between sICAM-1 and EC-SOD and disease activity. METHODS: Levels of sICAM-1 were measured in serum from 42 patients with active RA and 30 control subjects by enzyme-linked immunosorbent assay (ELISA). EC-SOD activity was determined in sera isolated from patients with active RA and from controls. RESULTS: The serum levels of sICAM-1 were significantly higher in patients with RA than in control subjects (p<0.001). In contrast, the activity of EC-SOD was significantly lower in RA patients than in healthy controls (p<0.001). A significant negative correlation was found between the levels of sICAM-1 and EC-SOD activity (r=-0.39, p<0.01). There was a statistically positive correlation between sICAM-1 levels with Ritchie articular index (RAI) score and C-reactive protein (CRP) (r=0.32, p<0.05; r=0.44, p<0.01, respectively). CONCLUSIONS: These results show that the increased levels of sICAM-1 present in active RA patients might be due to the decreased activity of EC-SOD, and increased levels of sICAM-1 may also reflect disease status or activity.

Adult↗

PubMed2001

Inhibitor effect of omeprazole in isolated human myometrial smooth muscle.

The aim of the present study was to investigate the effect of omeprazole, an H+-K+-ATPase inhibitor, in myometrial smooth muscle strips from women undergoing elective caesarean section at term. Isolated myometrial strips taken with informed consent were obtained from eight pregnant women undergoing elective caesarean section at term (not in labour) and mounted in organ baths for recording of isometric tension. We recorded the effect of increasing concentrations of omeprazole on spontaneous and Ca2+-induced contractions of myometrial smooth muscle and on contractions of myometrial smooth muscle pretreated with indomethacin (3 x 10(-6) M) and L-NAME (3 x 10(-5) M). Omeprazole (10(-4)-10(-3) M) decreased the amplitude and frequency of spontaneous contractions in a time- and concentration-dependent manner in all myometrial smooth muscle isolated from pregnant women. The decrease in amplitude of contractions in myometrial smooth muscle reached statistical significance beginning from the concentration of 3 x 10(-4) M. Addition of indomethacin (3 x 10(-6) M) and L-NAME (3 x 10(-5) M) in to the organ baths 30 min before did not change relaxation responses to omeprazole. When 8 mM Ca2+-precontracted in Ca2+-free medium myometrial smooth muscle were exposed to increasing concentrations of omeprazole (10(-5)-10(-3) M), omeprazole produced relaxation responses in a time- and concentration-dependent manner, reaching statistical significance at 10(-4) M. These results show: (1) omeprazole time- and concentration-dependently decreased spontaneous contractile activity in myometrial smooth muscle isolated from pregnant women, (2) omeprazole-induced relaxations was not influenced by indomethacin and N(G)-nitro-L-arginine methyl ester (L-NAME), suggesting that it is not mediated by cyclooxygenase products and nitric oxide, and (3) omeprazole brought about time- and concentration-dependently relaxation of myometrial smooth muscle precontracted by 8 mM Ca2+ in Ca2+-free medium. This effect of omeprazole may be due to blockade of the calcium channels.

Calcium↗

PubMed2000

Effects of exogenous testosterone on isolated rabbit corpus cavernosum penis.

AIM: To study the effects of exogenous excess of testosterone on the constricting effect of phenylephrine and endothelium-dependent and -independent relaxing effects of different agonists in the corpus cavernosum penis (CCP). METHODS: Specimens of the CCP were obtained from rabbits testosterone for 1 and 2 months and untreated for 2 months after testosterone-treatment for 2 months. Preparations were mounted between two parallel platinum electrodes in organ baths. Responses to phenylephrine, carbachol, and sodium nitroprusside were obtained by adding the reagent cumulatively to the bath. RESULTS: The phenylephrine-induced contractions were decreased with no change in agonist potency (pD2 value) after both 1 and 2 month testosterone-treatment and did not return to control values in corpus cavernosum obtained from rabbits untreated for 2 months after testosterone-treatment for 2 months. Testosterone treatment for 1 or 2 months increased the endothelium-dependent relaxations induced by carbachol and decreased the relaxations elicited by electric stimulation but did not affect the relaxations induced by sodium nitroprusside. These relaxant responses to carbachol and electric stimulation did not return to control values in corpus cavernosum obtained from rabbits untreated for 2 months after testosterone-treatment for 2 months. There were no significant changes in the pD2 values calculated by agonist-induced relaxation responses in all testosterone-treatment groups compared with control group. CONCLUSION: The exogenous excess of testosterone plays an important role in erectile function by a direct action on the relaxant and contractile responses of CCP.

Animals↗

PubMed1998

Effect of additional testosterone on purinergic responses in isolated rabbit corpus cavernosum strips.

Recently, it has been demonstrated that the endothelium of corpus cavernosum (CC) plays an important role on smooth muscle relaxation, which is crucial to initiate and maintain erection. We investigated the effect of long-lasting additional testosterone propionate (TP) therapy on endothelium-dependent and -independent relaxations of isolated rabbit CC. Isolated CC strips were mounted in organ baths and isometric tension was recorded. Addition of a specific inhibitor of nitric oxide synthesis, NG-nitro-L-arginin methyl ester (L-NAME), into the organ bath had no effect on the relaxation responses to adenosine (ADO), adenosine 5'-triphosphate (ATP) and sodium nitroprusside (SNP) in isolated CC strips precontracted with phenylepherine, but completely inhibited relaxation responses produced by ADP. Adenosine and adenine nucleotides relaxed the phenylepherine-induced contractile response in control strips with the potency order: ADO (62.8 +/- 3.2%) > ATP (37.1 +/- 5.2%) > ADP (25.8 +/- 2.5%). The relaxation responses to ADO, ATP and SNP in isolated rabbit CC strips were not significantly altered by additional TP therapy. The relaxation responses produced by ADP were significantly enhanced following 1 and 2 months TP therapy as compared with controls. However, in the group treated with TP for 2 months followed by a 2 months drug-free period, relaxation responses were significantly reduced compared to 1 and 2 months treatment groups, and approached control values. Increased relaxation responses to ADP following 1 and 2 months additional TP therapy may be a result of increased endothelial purinergic receptor density, or it may be due to stimulation and/or release of endothelial nitric oxide (NO) by TP.

Adenosine↗

PubMed1998

Treatment of closed femoral diaphyseal fractures with external fixators in children.

From August 1992 to July 1996, 57 patients with closed femoral fractures were treated by external fixator in the Orthopaedic and Traumatology Clinics, School of Medicine, Dicle University. The technique was applied to children with closed femoral fractures. Their mean age was 6 (range 4-12) years old. The mean hospitalisation period was 8 (range 5-15) days. Fixators were removed on an average of 55 (range 38-79) days. The mean follow-up period was 18 (range 9-36) months. Pintract infection was observed in 3 and refracture in 1 patient. Infection was controlled with oral antibiotics and local dressing. An external fixator was applied to a patient in whom refracture developed. No patient had malunion, nonunion, or leg length discrepancy. We propose that external fixation in closed femoral shaft fractures of children could be a rational alternative mode of therapy, since it has some advantages and can be easily removed without undergoing a second round of anaesthesia.

Child↗

PubMed1998

Tolerance to isosorbide dinitrate in isolated strips of rabbit corpus cavernosum.

The aim of this study was to investigate whether prolonged exposure to a high concentration of isosorbide dinitrate (ISDN) would result in tolerance being developed against its relaxant activity in strips of corpus cavernosum, pre-contracted by phenylephrine. Under these conditions, relaxation induced by ISDN was found to be significantly reduced. Strips made tolerant to ISDN remained fully responsive to sodium nitroprusside and papaverine. Electrical field stimulation evoked relaxations which were persistent in the presence of tolerance-inducing conditions. These results indicate that desensitization of guanylate cyclase activity is not likely to be the operating mechanism for nitrate tolerance. We suggest that tolerance may result from the impairment of biotransformation of ISDN in rabbit cavernosal smooth muscle.

Animals↗