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S Yilmaz

Publications and source records attributed to S Yilmaz.

At least 37 records · Page 2Linked to original sources
PubMed2005

The epidemiological aspects of irritable bowel syndrome in Southeastern Anatolia: a stratified randomised community-based study.

Even though studies on the epidemiology of the irritable bowel syndrome (IBS) are increasing day by day, epidemiological data are still unknown in many regions. Our objective was to determine the IBS prevalence, factors associated with this prevalence and probable risk groups in Southeastern Anatolia. The total population in the target region is approximately 6 million. A total of 3000 people (1521 females and 1479 males) randomly selected by stratified cluster sampling were interviewed face-to-face by using a questionnaire comprising demographic features and the Rome II criteria which also included probable risk factors and questions related with Bristol scale stool form. The statistical analysis was performed by using a package program called EPI INFO 2000. IBS prevalence was 10.2% according to the Rome II criteria in our region. Six hundred and twenty-five of 3000 subjects had gastrointestinal symptoms in the last 3 months. IBS rate was higher in women (12.4%) than in men (8.0%), and married subjects had higher IBS rates (11.6%) than singles (6.7%). Those differences were statistically significant (p = 0.000 for both). It was most common in the 35-54-year age group. No difference was observed in terms of settlement (rural/urban), age group, education and occupation. History of abortion in women increased the IBS risk by 1.8 times (p = 0.000 Crude odds ratios = 1.8 (1.3-2.6) 95% confidence intervals). Of the IBS patients, 48.1% had characteristics of diarrhoea-predominance, 38.9% constipation-predominance while 13.0% had none. There was a significant relation between dominant stool form and Bristol scale stool form. IBS prevalence is 10.2% in the first community-based study carried out in this specific subject in Southeastern Anatolia. The dominance of middle age and females remained significant.

Adolescent↗
PubMed2005

Magnetic resonance imaging guided catheterisation for assessment of pulmonary vascular resistance: in vivo validation and clinical application in patients with pulmonary hypertension.

OBJECTIVES: To validate in vivo a magnetic resonance imaging (MRI) method for measurement of pulmonary vascular resistance (PVR) and subsequently to apply this technique to patients with pulmonary hypertension (PHT). METHODS AND RESULTS: PVR was assessed from velocity encoded cine MRI derived pulmonary artery (PA) flow volumes and simultaneously determined invasive PA pressures. For pressure measurements flow directed catheters were guided under magnetic resonance fluoroscopy at 1.5 T into the PA. In preliminary validation studies (eight swine) PVR was determined with the thermodilution technique and compared with PVR obtained by MRI (0.9 (0.5) v 1.1 (0.3) Wood units.m2, p = 0.7). Bland-Altman test showed agreement between both methods. Inter-examination variability was high for thermodilution (6.2 (2.2)%) but low for MRI measurements (2.1 (0.3)%). After validation, the MRI method was applied in 10 patients with PHT and five controls. In patients with PHT PVR was measured at baseline and during inhalation of nitric oxide. Compared with the control group, PVR was significantly increased in the PHT group (1.2 (0.8) v 13.1 (5.6) Wood units.m2, p < 0.001) but decreased significantly to 10.3 (4.6) Wood units.m2 during inhalation of nitric oxide (p < 0.05). Inter-examination variability of MRI derived PVR measurements was 2.6 (0.6)%. In all experiments (in vivo and clinical) flow directed catheters were guided successfully into the PA under MRI control. CONCLUSIONS: Guidance of flow directed catheters into the PA is feasible under MRI control. PVR can be determined with high measurement precision with the proposed MRI technique, which is a promising tool to assess PVR in the clinical setting.

Adult↗
PubMed2005

Electrochemical study of natamycin--analytical application to pharmaceutical dosage forms by differential pulse voltammetry.

The electrochemical oxidation and determination of natamycin has been carried out at a carbon paste electrode in aqueous solutions in the pH range of 2.5-10.30 by cyclic and differential pulse voltammetry. Best results were obtained with the differential pulse voltammetric technique in 0.5 M sulfuric acid at pH 1.82. The diffusion controlled nature of the waves was established. A differential pulse voltammetric technique for the determination of natamycin 0.5 M sulfuric acid which allows quantitation over the range of 2 x 10(-6)-8 x 10(-5) M range method is proposed. Limit of detection and limit of quantitatification were 1.5 x 10(-6) and 5 x 10(-6) M, respectively. Based on this study a simple, rapid, selective and sensitive voltammetric method was developed for the determination of natamycin in capsules. In order to validate the proposed method, UV spectroscopy was applied.

Antifungal Agents↗
PubMed2005

A severe (type II) hepatopulmonary syndrome in a patient with idiopathic portal hypertension and treatment with paroxetine.

The hepatopulmonary syndrome has been defined as chronic liver disease accompanied by abnormal pulmonary gas exchange, which might result in arterial deoxygenation, and widespread intrapulmonary vasodilation. Although it has been pointed out that hepatopulmonary syndrome occurs in liver cirrhosis, there are a few studies in the literature reporting noncirrhotic portal hypertension as a cause of hepatopulmonary syndrome. Currently, liver transplantation is the only effective therapy for such patients. on the other hand, there is also a proposal about considering paroxetine, a potent nitric oxide synthase inhibitor, for use in the hepatopulmonary syndrome. We present a patient with severe (type II) hepatopulmonary syndrome caused by idiopathic portal hypertension and discuss the consequences of paroxetine therapy.

Adolescent↗
PubMed2004

The oxidative effect of prolonged CO2 pneumoperitoneum on renal tissue of rats.

BACKGROUND: Despite its advantages, laparoscopic donor nephrectomy is associated with prolonged operation time, which could potentially increase oxidative stress in the graft. We performed the first experimental, randomized, controlled study with blind assessment of outcome to address this possibility. METHODS: Wistar-Albino rats were randomized into three groups. The animals in the control group were subjected to a sham operation under anesthesia; the animals in the other two groups were subjected to CO(2) pneumoperitoneum (Pp) for 120 and 240 min, respectively. The kidneys were removed at the end of each experiment. The concentrations of protein carbonyl and sulfhydryl (SH) groups and the activities of superoxide dismutase (SOD) were measured in renal tissue samples as markers of oxidative stress. Renal tissue samples were also evaluated histopathologically using light microscopy. RESULTS: Exposure to 120 min of Pp significantly increased the finding of oxidative stress in renal tissue samples, with an increase in protein carbonyl content and a decrease in protein sulfhydryls and tissue (SOD) activities. When exposure to Pp was prolonged from 120 min to 240 min, Pp associated oxidative stress was found to be increased. These changes occurred in the absence of light microscopical evidence of overt tissue damage. CONCLUSIONS: In an experimental model resembling laparoscopic donor nephrectomy, we found that exposure of pneumoperitoneum prolonged from 120 min to 240 min acts as an additive factor with respect to causing increased oxidative stress in renal tissue. Because these effects imply subtle tissue injury that may contribute to the chronic demise of renal grafts obtained laparoscopically, avoiding the use of Pp if possible and keeping operation time less than 120 min during laparoscopic donor nephrectomy appear to be advisable.

Animals↗
PubMed2004

Angiographic follow-up after surgical treatment of intracranial aneurysms.

This study was undertaken to evaluate the long-term angiographic outcome of surgically treated aneurysms. In addition, the incidence of recurrent aneurysms, the fate of residual aneurysms and the de novo formation of aneurysms were evaluated. Moreover, morphological conditions such as dilatation, stenosis or irregularity in temporarily clipped vascular segments were analyzed.166 aneurysms were operated on in 136 patients and these 166 aneurysms subsequently underwent late follow-up angiography. Late angiographic follow-up review was obtained at a mean of 46.6+/-11.5 months postsurgery (range 36-85 months). Out of the 7 aneurysms with known residua, 5 residual aneurysms were determined as unchanged, 1 residual aneurysm as spontaneous thrombosis and 1 residual aneurysm as enlarged. No recurrent aneurysm was found, however two de novo aneurysms were found. During the surgery of 85 aneurysms, 137 vascular segments clipped temporarily were evaluated in terms of morphological changes in postoperative and long-term angiograms. No morphological changes were determined in any vascular segments. These anatomical long-term results confirm the long-term efficacy of aneurysm clipping, when perfect. Small residual aneurysms can be followed with periodically performed angiography.

Adolescent↗
PubMed2004

Laparoscopic management following ultrasonographic-guided drainage in a patient with giant paraovarian cyst.

BACKGROUND: Giant and paraovarian cysts are unusual masses that are usually treated by laparotomy. The safety of laparoscopic management of benign paraovarian cysts has been demonstrated, but it is believed that the size of benign paraovarian cysts is a limiting factor for laparoscopic surgery. METHODS: We describe a new technique for the laparoscopic removal of a giant and benign paraovarian cyst in a 40-year-old woman. A paraovarian cystic mass was detected on the right part of her body that extended to the liver. It was confirmed on both ultrasonography and computed tomography scans. After ultrasound-guided aspiration of the cyst, the mass was resected laparoscopically. RESULTS: No complications were noted during or after the surgical procedure. The patient was discharged on postoperative day 2. CONCLUSIONS: Laparoscopic surgery can be safely applied in patients with giant and benign paraovarian cysts.

Adnexal Diseases↗
PubMed2004

Expression of growth factors in the gingival crevice fluid of patients with phenytoin-induced gingival enlargement.

The mechanism underlying phenytoin (PHT)-induced gingival enlargement (GE) is not yet known. The aim of the present study was to investigate transforming growth factor-beta1 (TGF-beta1), platelet-derived growth factor-BB (PDGF-BB) and basic fibroblast growth factor (bFGF) profiles in the gingival crevice fluid (GCF) of patients with PHT-induced GE and to compare the results with healthy controls. Five PHT-treated patients and five healthy subjects with normal periodontal tissue were included in this study. GCF samples were collected from (i) enlarged gingival sites in patients receiving PHT (GE+); (ii) non-enlarged gingival sites in the same patients (GE-); (iii) normal gingival sites of healthy subjects (control). The levels of TGF-beta1, PDGF-BB and bFGF in the GCF samples were analysed by ELISA. The results showed that the total amounts of TGF-beta1 and PDGF-BB in the GE+ group were higher than in the GE- group and significantly higher than in the control group (P < 0.05). However, no significant differences were found between the groups when the concentrations of these growth factors were compared. bFGF levels were not compared as this growth factor could be detected in only 33, 41 and 44% of the GE+, GE- and control GCF samples, respectively. These results show that TGF-beta1 and PDGF-BB are readily detectable in GCF obtained from enlarged and non-enlarged sites of PHT recipients and suggest that since the amounts were markedly higher at the GE+ than the GE- sites, the systemic administration of PHT has a pronounced localised effect on the levels of these growth factors. Moreover, our findings provide evidence that both TGF-beta1 and PDGF-BB are closely associated with the clinical manifestation of PHT-induced GE.

Adolescent↗
PubMed2004

Reconstruction of the vena cava with the peritoneum: the effect of temporary distal arteriovenous fistula on patency (an experimental study).

OBJECTIVE: To determine the effect of increasing inferior vena cava blood flow by means of distal arteriovenous fistula on the patency of a peritoneal tube graft. MATERIALS AND METHODS: In 16 mongrel dogs, a 3-4 cm long circular defect was created at the infrarenal inferior vena cava. The defect was interposed with peritoneal tube graft. A temporary distal femoro-femoral arteriovenous fistula was also constructed in 8 dogs just after the caval interposition. Graft patency was evaluated by Doppler ultrasonography and angiography. Histological evaluation was also performed. RESULTS: Seven dogs in each group survived. All control grafts occluded within the first week, compared to no occlusions in fistula group (Fisher's exact test, p<0.005). However one 'fistula' dog with a still patent graft was sacrificed on the 18th day due to ultrasonographically occluded arteriovenous fistula. CONCLUSION: In dogs, the peritoneum may be used as graft material for reconstruction of the inferior vena cava, provided a distal arteriovenous fistula is constructed.

Animals↗
PubMed2004

[Right heart failure due to pulmonary tumor microembolism -- a rare differential diagnosis].

A 69-year-old man presented with progressive dyspnea, hemoptysis and fatigue for the previous 4 weeks. Chest radiograph and CT-scan were suggestive of lung cancer. The patient's condition worsened and within in few days he developed respiratory failure and acute cor pulmonale. Despite intensive care measures directed at suspected lung thromboembolism, the patient died on day 12. Autopsy revealed disseminated obstruction of small pulmonary arteries by microscopic tumor emboli. No signs of venous thromboembolism were found. Pulmonary tumor microembolism should be considered whenever a patient with malignancy presents with unexplained progressive dyspnea or pulmonary hypertension.

Autopsy↗
PubMed2004

Cytotoxicity of composite resins polymerized with different curing methods.

AIM: To compare the relative cytotoxicity of resin-based composite materials polymerized with three different curing methods on L 929 cells over a period of 1 week. METHODOLOGY: Ten discs of each material (Flowline, P 60 and Z 250) were cured from one side with either standard cure (Optilux 401), soft-start cure (Elipar Free Light) or fast cure (Hilux Ultra Plus). Then the samples were aged for 1, 2, 3, 5 and 7 days in Dulbecco's Modified Eagle Medium/Ham's F12 (DMEM/F12). After each ageing interval, cytotoxicity of the extracts to cultured fibroblasts (L 929) was measured by MTT assay. The degree of cytotoxicity for each sample was determined according to the reference value represented by the cells with a pure culture medium. Statistical significance was determined by one-way analysis of variance (anova), followed by the Student's Newman-Keuls test. RESULTS: Exposure of L 929 cells to the test materials resulted in a high survival fraction at 1 and 7 days. Flowline specimens, either cured with Optilux 401 or Elipar Free Light, had no toxic effect on the cells, whereas the other groups were moderately toxic on the 2-day interval. All experimental groups presented lower cell viability than the control at the 3- and 5-day intervals. CONCLUSIONS: The composite resins used in this study were cytotoxic after 48 h pre-incubation, but this toxicity disappeared after pre-incubation in a biological medium for 7 days. Curing did not have a significant effect on the cytotoxicity of the composite materials tested.

Analysis of Variance↗
PubMed2004

The venous drainage of the heart in porcupines (Hystrix cristata).

The venous drainage of the heart in porcupines (Hystrix cristata) was investigated. Each of the five adult porcupines (three males, two females) was injected with a coloured latex mixture via the V. cava caudalis for the demonstration of the cardiac veins. The dissection of the specimens revealed that the venous drainage of the heart in porcupines was made by the V. cordis magna, V. distalis ventriculi sinistri, V. proximalis ventriculi sinistri, V. cordis caudalis (the left marginal vein), V. cordis media and Vv. cordis dextrae. The cardiac veins were observed in a subepicardial course on the heart except for the R. interventricularis paraconalis. The R. interventricularis paraconalis showed an intramyocardial course until the middle of the sulcus interventricularis paraconalis, and a subepicardial course after this point. The V. cordis magna and V. distalis ventriculi sinistri opened to the sinus coronarius. The V. cordis caudalis and the V. cordis media drained into the V. cava caudalis. The venous drainage of the conus arteriosus was made by the left V. coni arteriosi opening to the R. interventricularis paraconalis, and by the right V. coni arteriosi which continued to the Vv. cordis dextrae.

Animals↗
PubMed2004

Lightning: an unusual cause of cerebellar infarction.

The neurological complications of lightning injury are not infrequent. However, scarce data are available on cerebellar infarction attributable to lightning injury. A 45 year old man was admitted to the emergency department because of lightning injury. The patient had a Glasgow coma scale score of 13/15 on arrival at hospital with accompanying dysarthria and hypotonia. Computed tomography of the head showed only a mild cerebral oedema. Ataxia was recorded on the fourth day. Magnetic resonance imaging of the head showed ischaemia predominantly in the cerebellar hemispheres bilaterally and in the parietal, temporal, and frontal lobes on the right. Anti-oedema treatment was started. The patient was discharged after seven days. After one month the patient was re-examined and found to have minimal ataxia and dysarthria. Lightning injury should not be overlooked in the aetiology and differential diagnosis of acute cerebellar ischaemic insult and relevant clinical findings in adults.

Brain Infarction↗
PubMed2003

Mesenteric cysts.

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Bibliometrics↗
PubMed2003

The effect of different intraabdominal pressures on lipid peroxidation and protein oxidation status during laparoscopic cholecystectomy.

BACKGROUND: This prospective, randomized, and controlled study was designed to investigate the effects of different intraabdominal pressures (IAPs) on lipid peroxidation and protein oxidation status during laparoscopic cholecystectomy (LC). METHODS: Twenty-four patients (12 men, 12 women) who underwent LC at either 10 or 15 mmHg of IAP were randomized into two groups. Repeated blood samples were collected to measure thiobarbituric acid reactive substances (TBARS) levels to assess lipid peroxidation and protein carbonyl content and protein sulfhydryl groups to assess protein oxidation status. RESULTS: Serum protein carbonyls and TBARS levels were found to be increased immediately after desufflation in both study groups when compared to the preoperative levels. On the other hand, protein sulfhydryl levels were found to be decreased in both study groups. Although increases in protein carbonyls and TBARS levels were more prominent in patients who underwent LC at 15 mmHg of IAP, this difference was not statistically significant between both groups. CONCLUSIONS: The results suggest that both 15 and 10 mmHg of LAP could lead to an increased oxidative stress response during LC, but no difference was found between the groups.

Adult↗
PubMed2003

Can preconditioning reduce laparoscopy-induced tissue injury?

BACKGROUND: Pneumoperitoneum (P) created to facilitate laparoscopy (L) is associated with splanchnic perfusion, ischemia/reperfusion (I/R) injury, and oxidative stress. In this randomized controlled experimental study with blind outcome assessment, we evaluated the effect of preconditioning (PRE) on L-induced I/R injury. METHODS: The subjects were 40 Sprague-Dawley male rats. P was created in all except controls, using carbondioxide (CO2) insufflation under a pressure of 15 mmHg. PRE consisted of 10 min of P, followed by 10 min of deflation (D). The rats were randomized to the following groups: Group P was subjected to 60 min of P. Group P/D was subjected to 60 min of P, followed by 45 min of D. Group PRE/P was subjected to PRE, followed by 60 min of P. Group PRE/P/D was subjected to PRE, followed by 60 min of P and 45 min of D. Group C (control) was subjected to a sham operation, without P. Its anesthesia time was equal to that for group PRE/P/D. At the end of the experiments, the rats were killed; blood, liver, and kidney samples were then obtained and coded. Plasma alanine aminotransferase (ALT) and malondialdehyde (MDA), as well as homogenized tissue MDA levels and glutathione (GSH) activities, were measured; tissue samples were assessed for histopathological evidence of injury; all assessments were done by investigators blinded to the study design. The results were decoded and analyzed statistically with the Kruskal-Wallis and Mann Whitney tests. A p <0.05 was considered significant. RESULTS: Plasma ALT as well as plasma, liver, and kidney MDA levels and liver and kidney injury scores were increased, whereas liver and kidney GSH values were decreased in groups P and P/D, as compared to group C. Rats subjected to PRE before P had plasma ALT, kidney MDA, and kidney and liver GSH levels comparable to controls; their kidney and liver injury scores were higher than controls but significantly lower than nonpreconditioned animals. PRE enabled decreased plasma, kidney, and liver MDA as well as increased kidney GSH if applied before P; its efficacy on oxidative stress was limited to providing decreased kidney MDA and increased kidney GSH if applied before P/D. However, PRE significantly attenuated kidney and liver injury after P as well as P/D. CONCLUSION: PRE consisting of 10 min of P followed by 10 min of D decreases the oxidative stress induced by sustained P in the plasma, liver, and kidney. PRE significantly limits liver and kidney injury after prolonged P and P/D. After further studies to define its ideal timing, PRE before L incorporating P may have clinical relevance, especially for elderly patients or those with impaired hepatic and/or renal function or perfusion.

Alanine Transaminase↗