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N Yilmaz

Publications and source records attributed to N Yilmaz.

54 records · Page 3Linked to original sources
PubMed1998

Determination of terbutaline based on oxidation by voltammetry.

A voltammetric study of the oxidation of terbutaline has been carried out at an activated glassy carbon electrode. The compound was oxidized irreversibly at high positive potential. The response was evaluated with respect to pH, scan rate, nature of the buffer and other variables. The peak current, at about 0.8 V (versus a saturated calomel electrode), was proportional to the terbutaline concentration in the range of 8 x 10(-6)-8 x 10(-4) M in phosphate buffer pH 6.0. This method was applied, without any interferences from the excipients, to determine the drug in a tablet dosage form.

Adrenergic beta-Agonists↗
PubMed1998

Anodic voltammetry of cefotaxime.

In this study electrooxidation of cefotaxime was investigated using specially activated glassy carbon (GC), platinum and carbon paste (CP) electrodes in different supporting electrolyte solutions and at different pHs. The data revealed that the shapes of the voltammograms and the numbers of the oxidation steps changed depending on the nature of the electrode. The nature of the supporting electrolyte was also important for the response of the electrode. From an analytical point of view, the activated GC electrode was the most favourable one. In 0.2 M H3PO4 with an activated GC electrode the calibration graph gave two lines with different slopes in the concentration ranges of 2 x 10(-5)-1 x 10(-4) and 2 x 10(-4)-6 x 10(-4). The results of the recovery test and statistical analysis showed that the voltammetric method could be used for the determination of cefotaxime.

Cefotaxime↗
PubMed1998

The effect of different anaesthetic agents in hearing loss following spinal anaesthesia.

The cause of hearing loss after spinal anaesthesia is unknown. Up until now, the only factor studied has been the effect of the diameter of the spinal needle on post-operative sensorineural hearing loss. The aim of this study was to describe this hearing loss and to investigate other factors influencing the degree of hearing loss. Two groups of 22 similar patients were studied: one group received 6 mL prilocaine 2%; and the other received 3 mL bupivacaine 0.5%. Patients given prilocaine were more likely to develop hearing loss (10 out of 22) than those given bupivacaine (4 out of 22) (P < 0.05). The average hearing loss for speech frequencies was about 10 dB after prilocaine and 15 dB after bupivacaine. None of the patients complained of subjective hearing loss. Long-term follow-up of the patients was not possible.

Adult↗
PubMed1998

Plasma immunadsorption treatment in patients with primary focal and segmental glomerulosclerosis.

BACKGROUND: In primary focal and segmental glomerulosclerosis (FSGS) renal prognosis is poor if no remission of proteinuria can be obtained by treatment. In some patients a permeability factor, responsible for damaging the glomerular epithelial cell and detectable by an in vitro test (GVV-test), seems to be present in the serum. METHOD: We determined the effects of an immunadsorption treatment (IAT) on proteinuria and glomerular permselectivity (using a neutral dextran and dextransulfate-sieving technique to assess glomerular size and charge selectivity) in five patients with FSGS in the native kidneys and three patients with recurrence of FSGS after kidney transplantation. Furthermore, we performed the GVV-test using sera obtained from the patients before and after therapy. RESULTS: IAT reduced proteinuria by more than 50% in four patients, all of whom had an improvement in glomerular-size selectivity. Charge selectivity was better preserved after therapy in three out of these four subjects. The GVV-test prior to IAT was positive in two patients who also responded clinically to therapy. After IAT the GVV-test was negative in all patients, indicating an elimination of the proteinuric factor in the two previously positive patients. CONCLUSION: We conclude that a positive GVV-test before treatment makes a favourable response of IAT on proteinuria likely in patients with FSGS. If a reduction of proteinuria can be obtained by IAT this is due to an improvement in glomerular size and/or charge selectivity.

Adolescent↗
PubMed1998

Angiotensin-converting enzyme gene polymorphism determines the antiproteinuric and systemic hemodynamic effect of enalapril in patients with proteinuric renal disease. Austrian Study Group of the Effects of Enalapril Treatment in Proteinuric Renal Disease.

Angiotensin-converting enzyme (ACE) inhibitors are known to reduce blood pressure and proteinuria in a variety of different glomerular diseases. Nonetheless, a marked interindividual difference in the efficacy of these agents exists. The activity of the ACE and therefore of the renin-angiotensin-aldosterone system (RAAS) has been shown to be under genetic influence. Patients with a deletion genotype at the intron 16 of the ACE gene have been shown to exhibit higher activity of plasmatic ACE when compared to patients with the insertion genotype. We therefore studied prospectively the hemodynamic and antiproteinuric effect of a 6-month therapy with enalapril in patients with biopsy-proven proteinuric glomerular diseases and the DD (n = 10) and ID/II (n = 26) genotype. Although patients with the DD genotype received a slightly higher dose of enalapril, blood pressure and proteinuria did not change significantly. However, both were significantly reduced in the II/ID group after 10 weeks and 6 months of therapy. Creatinine clearance decreased steadily in DD patients. In II/ID patients, creatinine clearance was reduced significantly after 10 weeks of therapy but increased again thereafter and the value at 6 months was again comparable to the one obtained in the DD patients. We conclude from our study that the ACE genotype influences the blood pressure-lowering and antiproteinuric effect of enalapril in patients with proteinuric glomerular disease.

Adult↗
PubMed1997

Low dose angiotensin converting enzyme inhibition and glomerular permselectivity in renal transplant recipients.

In this study, we determined the fractional clearance of neutral polydisperse dextrans (theta D) and monodisperse dextran sulfate (theta DS) to describe glomerular size and charge selectivity in 25 renal transplant recipients with proteinuria. Thirteen were treated with low dose lisinopril for six months (group 1) and 12 patients without ACE inhibitor therapy formed group 2. Mean arterial blood pressure was stable (group 1, 112 +/- 4; group 2, 109 +/- 2 mm Hg at baseline and after 6 months) whereas creatinine clearance, glomerular filtration rate and renal plasma flow decreased nonsignificantly but were comparable at any time. Lisinopril treatment lowered filtration fraction (22 +/- 2 vs. 19 +/- 2%, P = 0.07) whereas no change was seen in group 2 (20 +/- 2%). The fractional protein excretion (mg urinary protein per day/ml creatinine clearance per day) was stable in group 1, but significantly increased in group 2. The same pattern was found for theta D larger than 56 A. theta DS was stable and consistently elevated in both groups at any time. We conclude that low dose ACE inhibitor treatment in proteinuric renal transplant recipients stabilizes glomerular size selectivity independently of its systemic hemodynamic effects.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1997

Angiotensin converting enzyme insertion/deletion polymorphism and short-term renal response to ACE inhibition: role of sodium status.

Angiotensin converting enzyme (ACEi) inhibition retards renal function loss, but the therapeutic benefit varies between individuals. Renoprotection is poor in patients with the ACE DD genotype. ACE genotype is reported to affect short-term antiproteinuric response to ACEi, a predictor of long-term renoprotection, in some studies but not in others. Short-term responses to ACEi are enhanced by stimulating the renin-angiotensin system, that is, sodium restriction. We hypothesized that the ACE genotype influences sodium dependency of the response to ACEi. Therefore, we performed a cross sectional analysis of short-term responses to ACEi (enalapril or lisinopril) in 88 patients with stable non-diabetic proteinuria (> 1.0 g/day) and variable sodium intake. ACE genotype distribution was: DD, N = 25; ID, N = 40; II, N = 23. Baseline proteinuria (5.9 +/- 0.7; 5.8 +/- 0.07; 4.8 +/- 0.8 g/day, respectively) and mean arterial pressure (108 +/- 3; 106 +/- 2; 107 +/- 2 mm Hg, respectively) were similar for the three genotypes. ACEi similarly reduced proteinuria (-49 +/- 5; -55 +/- 4, -48 +/- 6%, respectively) and blood pressure (-12 +/- 3; -14 +/- 1 and -12 +/- 2%, respectively) in the three groups. Interestingly, the responses to ACEi of proteinuria (r = 0.42, P < 0.05) and blood pressure (r = 0.41, P < 0.05) correlated with urinary sodium excretion in DD genotype but not in the ID (r = 0.05 and 0.17, resp) or II genotype (r = 0.09 and 0.08, respectively). Thus, in the DD group, individuals with a high sodium excretion had a less effective response to ACEi. We conclude that differences in sodium status could account for disparities between studies on the relationship between ACE genotype and response to ACEi, and that sodium restriction might be a strategy to circumvent treatment resistance in the DD genotype.

Adolescent↗
PubMed1996

Renal function and glomerular permselectivity late after living related donor transplantation.

Living related kidney transplantation is the preferable procedure for renal replacement therapy. The aim of the current study was to determine systemic hemodynamic and intrarenal adaptions in donors and recipients late after living related kidney transplantation. Furthermore, glomerular permselectivity was assessed in these subjects. We studied mean blood pressure (MAP), glomerular filtration rate (GFR), renal plasma flow (RPF), microalbuminuria (MIA), 24-hr urinary protein excretion, and glomerular permselectivity (fractional clearance of neutral dextrans [thetaD] as a marker for size selectivity and fractional clearance of dextran sulfate [thetaDS] to assess charge selectivity) in 22 donors and 22 recipients. MAP was normal in the donor group (102 +/- 4 mmHg), but five patients had blood pressure above 140/90 mmHg. This 18%, however, is lower than the prevalence of hypertension in the age-adjusted general population in Austria. The recipients also had normal MAP at the time of study (99 +/- 3); however, 13 needed antihypertensive therapy. GFR and RPF were lower in recipients than in donors (53 +/- 8 vs. 72 +/- 11 and 314 +/- 74 vs. 412 +/- 86 ml/min respectively). In the donor group, GFR was 137 +/- 45% of the expected age-adjusted mean value/kidney due to hyperfiltration. Proteinuria and MIA were higher in the recipients than in the donors (0.39 +/- 0.22 vs. 0.07 +/- 0.04 g/day, 137 +/- 136 vs. 26 +/- 15 mg/day). Nonetheless, five donors had an elevated MIA. A higher need for antihypertensive medication could be observed in recipients with previous rejection episodes, as well as a significantly higher urinary protein excretion and MIA (0.7 +/- 0.42 vs. 0.24 +/- 0.14 g/day, 336 +/- 380 vs. 48 +/- 32 mg/day). ThetaDS was significantly higher in the recipients, whereas thetaDS of the donors was identical to the value obtained from 18 healthy controls (0.7 +/- 0.08 vs. 0.6 +/- 0.06). OD was similar in all groups studied. In conclusion, 76 months after uninephrectomy for renal donation, mild changes in glomerular permselectivity occurred in a subset of donors without affecting renal excretory function. In recipients, proteinuria was due to a defect in glomerular charge selectivity.

Adult↗
PubMed1996

Evaluation of patients with epilepsy: an outpatient clinic based study.

In order to identify the demographic features, seizure types and epilepsies, we reviewed the files of 1379 patients admitted to the epilepsy outpatient clinic of Bakirköy State Hospital for Neurological and Psychiatric Diseases between 1991 and 1994. Of these, 160 patients' files contained inadequate information and 80 patients with nonepileptic events were excluded from the study. There were 523 female and 616 male patients ranging in age from 6 months to 87 years. Risk factors could be identified in 612 (54.3%) of patients. Some 62.1% of patients had partial and 34.8% had generalized seizures, whilst 71.0% were classified as partial and 11.9% as generalized epilepsies. Two per cent were classed as special syndromes and 15% as undetermined. In our series the unclassified cases represented 3.1% of the total. We discuss the results and compared them with other studies.

Adolescent↗
PubMed1994

Pomeroy tubal ligation by laparoscopy and minilaparotomy.

Pomeroy tubal ligation is a widely-used method for surgical female sterilization. A laparoscopic technique of Pomeroy tubal ligation using endoloop sutures is compared with the conventional technique of Pomeroy tubal ligation by minilaparotomy. Forty-four women requiring sterilization were randomly selected for either laparoscopy (n = 24) or minilaparotomy (n = 20). Mean operative time in the laparoscopy group (18.90 +/- 5.56 with a range of 12-35 minutes) was not significantly different from that in the minilaparotomy (23.12 +/- 8.24 with a range of 15-45 minutes) group. In all women, tubal specimens confirmed tubal histology. Both laparoscopy and minilaparotomy procedures may be performed for Pomeroy tubal ligation with minor morbidity. In clinics with appropriate conditions, Pomeroy tubal ligation by laparoscopy may be preferable to minilaparotomy.

Adult↗
PubMed1990

The Schinzel-Giedion syndrome. A case report and review of the literature.

The authors discuss a 1-day-old boy who had Schinzel-Giedion syndrome. This is the fifth case reported in the literature, and it presents additional abnormalities that have not been reported previously. The Schinzel-Giedion syndrome includes facially dysmorphic, skeletal, cardiac, and genito-urinary anomalies, but mainly congenital hydronephrosis. The diagnosis can be made by clinical and radiological examinations.

Abnormalities, Multiple↗
PubMedDate not supplied

Interferon alpha-2b may impair testicular histology including spermatogenesis in a rat model.

Interferon-alpha has been used in various diseases at the reproductive ages. However, the effect of interferon-alpha on testicular histology has not been studied in literature. The aim of this study was to investigate the effects of interferon alpha-2B on testicular histology including spermatogenesis in a rat model. Seventeen adult male Wistar albino rats were divided into 3 groups: Six rats received 7.500 units (5 MIU/m2) of interferon alpha-2B (Intron), considered clinical treatment dose range. Six rats received 30.000 units (20 MIU/m2) of interferon alpha-2B (Intron), considered high treatment dose. Five rats served as a control group receiving 0.5 mL of saline injection. All injections were done intraperitoneally 3 times weekly for 3 weeks under inhalation anesthesia. All rats underwent bilateral orchiectomy 30 days after the experiment. Histological examination included the mean seminiferous tubular diameter (STD), germinal epithelial cell thickness (GECT), and testicular biopsy score (TBS). The mean STD was significantly lower in the low-dose interferon and high-dose interferon groups than in the control group (p = 0.008 and p = 0.004, respectively). The mean GECT was significantly lower in the low-dose interferon and high-dose interferon groups than in the control group (p = 0.008 and p = 0.004, respectively). The mean TBS was significantly lower in the low-dose interferon group (p = 0.05) and the high-dose interferon group (p = 0.01) than in the control group. The decreases in the mean values of the STD, GECT and TBS were not related to the interferon dose. Interferon alpha-2B may impair testicular histology even in clinical widely used treatment dose. Therefore, men at the reproductive ages should be fully informed for the use of interferon-alpha in the treatment of various diseases.

Animals↗
PubMedDate not supplied

Acute optic neuropathy in Behçet disease.

PURPOSE: To report a patient with Behcet disease presenting with acute optic neuropathy. METHODS: A 47-year-old man was admitted to the authors' clinic owing to sudden visual loss in the left eye. Ophthalmologic and systemic examinations were performed. RESULTS: Visual acuity was 4/10 in the left eye. Fundus examination demonstrated swollen optic disc with blurred margins. There was relative afferent pupil defect in the same eye. Mega-dose corticosteroid treatment was started with the diagnosis of acute optic neuropathy. Ocular findings resolved within 2 weeks. CONCLUSIONS: Behçet disease rarely presents with acute optic neuropathy.

Acute Disease↗
PubMedDate not supplied

Fused pelvic kidney drained by a single ureter.

A case of fused pelvic (discoid) kidney drained by a superiorly inserted single ureter is presented. This is the twentieth case of fused pelvic kidney, and the fifth case in which drainage was carried out by a single ureter, to be reported in the English literature. The diagnosis and treatment of this condition is discussed and the relevant literature is reviewed.

Child, Preschool↗