Mustafa Usta - Academia.edu (original) (raw)

Papers by Mustafa Usta

Journal of Internal Medicine, 2002

SUMMARY Walnut orchards of the Lake Van basin (Turkey) were surveyed from June to October 2006 to... more SUMMARY Walnut orchards of the Lake Van basin (Turkey) were surveyed from June to October 2006 to determine the incidence of viral infections. ELISA and RT-PCR were used to investigate the presence of Cherry leaf roll virus (CLRV) and Plum pox virus (PPV), testing a total of 870 samples collected from traditional seed-grown plantations. Whereas no PPV was detected in

The journal of sexual medicine, 2006

Accumulation of advanced glycation end products (AGEs) has been linked to many of the complicatio... more Accumulation of advanced glycation end products (AGEs) has been linked to many of the complications of diabetes mellitus, including erectile dysfunction (ED). Furthermore, it has been demonstrated that inhibitors of AGE formation, such as aminoguanidine, can prevent ED in diabetic animals. However, it is unknown whether late administration of a putative cross-link breaker, ALT-711, can reverse diabetic ED. We therefore compared ALT-711 and aminoguanidine in their ability to reverse ED in diabetic rats. Male Sprague-Dawley rats were randomly divided into four groups: (i) age-matched controls; (ii) streptozotocin (STZ)-induced diabetic rats (60 mg/kg; intraperitoneal injection); (iii) STZ diabetic rats treated with ALT-711 (3 mg/kg/day, intraperitoneal injection); and (iv) STZ diabetic rats treated with aminoguanidine (1 gm/L in drinking water) during the final 6 weeks of 12 weeks of induced diabetes. At the end of 12 weeks, erectile response to cavernous nerve stimulation (CNS) was d...

The Journal of urology, 2004

We investigated the relationship between penile curvature severity and co-morbidities in men with... more We investigated the relationship between penile curvature severity and co-morbidities in men with Peyronie's disease (PD) and assessed whether the severity of curvature had an impact on penile vascular status and/or erectile function. Based on a 10-year period 469 patients with PD were retrospectively evaluated in regard to age at diagnosis, type and degree of penile curvature, erectile dysfunction (ED) and other comorbidities, such as diabetes mellitus, hypertension, serum lipid abnormalities, smoking and ischemic heart disease. To assess penile vascular status all men with PD underwent penile duplex Doppler ultrasound evaluation. The severity of penile curvature was classified using the Kelami system, that is grade 1--curvature 30 degrees or less, grade 2--30 to 60 degrees and grade 3--greater than 60 degrees. Mean patient age was 54.8 +/- 4.3 years (range 18 to 79) and the mean duration of symptoms was 24.8 +/- 13.7 months (range 3 to 120). The most common penile abnormality ...

The Journal of urology, 2003

Erectile dysfunction (ED) is frequently associated with diabetes mellitus. We determined if advan... more Erectile dysfunction (ED) is frequently associated with diabetes mellitus. We determined if advanced glycation end products (AGEs) are involved in ED and investigated if the selective AGE and inducible nitric oxide synthase (iNOS) inhibitor aminoguanidine (AG) could protect against the development of ED in a diabetic rat model. Harlan Sprague-Dawley rats were divided into 3 groups. The 9 nondiabetic rats in group 1 served as age matched controls. Diabetes was induced in the 9 rats in groups 2 and 3, respectively, by intraperitoneal injection of streptozocin (60 mg/kg). While group 2 was given free access to water and a standard diet, group 3 was treated with AG added to drinking water (1 gm/l daily). Two months after diabetes induction in vivo intracavernous pressure measurements were determined. Penile tissue glycation (furosine on high performance liquid chromatography), AGEs (pentosidine on high performance liquid chromatography and immunohistochemistry), AGE receptor (galectin-3...

Urology, 2002

To investigate the impact of chronic renal failure (CRF) on advanced glycation end product and in... more To investigate the impact of chronic renal failure (CRF) on advanced glycation end product and inducible nitric oxide synthase (iNOS) in penile tissue, we examined the advanced glycation end product 5-hydroxy methyl furfural (5-HMF) content and iNOS expression in rats in which uremia had been produced by greater than 85% nephrectomy. In addition, the contribution of peritoneal dialysis (PD) fluids to the elevation of penile tissue 5-HMF levels and iNOS staining scores has been investigated. Adult male Wistar rats, aged between 10 and 12 weeks and weighing 200 to 330 g, were divided into five groups that each included 6 animals. The first group served as a control group. In the second group, CRF was induced and a peritoneal catheter was implanted, but PD was not performed. In group 3, CRF was induced and PD was performed using dialysis fluids containing 1.36% glucose and icodextrin. In group 4, CRF was also induced and PD was performed using 3.86% glucose and icodextrin. Finally, in ...

Erectile dysfunction (ED) is defined as the consistent inability to obtain or maintain an erectio... more Erectile dysfunction (ED) is defined as the consistent inability to obtain or maintain an erection for satisfactory sexual intercourse. Basic science research on erectile physiology has been devoted to investigating the pathogenesis of ED and has led to the conclusion that ED is ...

Biochemical Pharmacology, 2005

In the present study, the effects of a large series of flavonoids on multidrug resistance protein... more In the present study, the effects of a large series of flavonoids on multidrug resistance proteins (MRPs) were studied in MRP1 and MRP2 transfected MDCKII cells. The results were used to define the structural requirements of flavonoids necessary for potent inhibition of MRP1- and MRP2-mediated calcein transport in a cellular model. Several of the methoxylated flavonoids are among the best

The etiologies of erectile dysfunction (ED) after nerve- sparing radical prostatectomy have not b... more The etiologies of erectile dysfunction (ED) after nerve- sparing radical prostatectomy have not been clearly elucidated. The aim of this study was to evaluate the effects of cavernous nerve injury on cavernous fibrosis, and to consider measures to prevent irreversible damage to the cavernous tissues. Twenty male Sprague-Dawley rats constituted the study population. The animals were divided into 2 groups;

Polymer Degradation and Stability, 2003

In this study, we investigated that how the crystalline structure of cellulose in cotton linters ... more In this study, we investigated that how the crystalline structure of cellulose in cotton linters changed during soda, sulfate and organosolve pulping processes by using X-ray diffraction and FT-IR spectroscopy. It was defined that crystalline structure of cellulose in cotton linters was more effected in organosolve pulping than in soda and sulfate pulping. It was found that the degree of

Bju International, 2002

To investigate the value of penile scintigraphy using 99mTc-human immunoglobulin G (IgG) to diffe... more To investigate the value of penile scintigraphy using 99mTc-human immunoglobulin G (IgG) to differentiate the unstable (acute) and stable (chronic) phases of Peyronie's disease (PD). Thirty-two consecutive patients (25 with PD and seven without) were evaluated using a detailed sexual history, serum chemistry panel, colour Doppler ultrasonography during simultaneous intracavernosal injection of 50 mg papaverine and stimulation, and 99mTc-IgG scanning. When indicated, nocturnal penile tumescence monitoring, dynamic infusion cavernosometry, cavernosonography and cavernosal artery systolic occlusion pressure were measured. After administering 370 MBq of 99mTc-IgG, images were taken at 30 min, 1, 2, 3 and 4 h. The scans were considered positive if there was any focal accumulation of radiopharmaceutical consistent with PD plaque formation. Eleven of the 25 patients with PD (mean age 56 years, sd 8) were in the unstable phase, the remaining 14 being in the stable phase. There was a localized increase in 99mTc-IgG activity in 10 patients who had unstable PD. There was complete resolution of increased activity in two patients at 12 and 13 months of follow-up. Of the 14 patients in the stable phase, 12 (at > 1 year) showed neither increased nor decreased 99mTc-IgG activity. In the remaining two patients there was increased activity on the plaque side. There was no local increase in activity in the control group. Inflammatory reactions can develop at various intervals during the unstable phase of PD. Medical methods should be used during the unstable phase and surgery delayed until the stable phase of the disease begins. An objective method of differentiating between the phases is therefore important. Penile 99mTc-IgG imaging is a new diagnostic approach for confirming the unstable phase of PD.

Urologia Internationalis, 2002

The induction of apoptosis has emerged as a potential target for optimization of the medical mana... more The induction of apoptosis has emerged as a potential target for optimization of the medical management of benign prostatic hyperplasia (BPH), recently. The influence of alpha1-adrenoceptor antagonist (alpha1-ARA), 5-alpha reductase inhibitor and their combination on prostatic cell apoptotic and proliferative indices of benign hyperplastic prostate gland were investigated. A total of 49 male patients with BPH (mean age: 66.5 years) treated with alpha1-ARA and/or finasteride were retrospectively evaluated. Patients treated with alpha1-ARA (doxazosin n = 12 and terazosin n = 10), finasteride (n = 9) and combination of finasteride and alpha1-ARA (n = 9) were enrolled in the study. Primary antibodies were Ki-67 and proliferating cell nuclear antigen for the evaluation of proliferation in prostate stromal and epithelial cells. In situ apoptotic DNA fragmentation was evaluated using TUNEL assay. All treatment groups had no significant changes in the rate of prostate stromal and epithelial cell proliferation. Epithelial apoptotic index (AI) was not statistically significant for finasteride vs. alpha1- ARA, alpha1-ARA vs. finasteride + alpha1-ARA and finasteride + alpha1-ARA vs. finasteride groups. While alpha1-ARA was more effective than finasteride on stromal apoptosis, alpha1-ARA-induced stromal apoptosis was not significantly different from alpha1-ARA plus finasteirde treatment. Not only androgen variabilities but also alterations in sympathetic neurotransmission with age could have important implications for pathophysiological prostate growth. The combination of finasteride and alpha1-ARA is not superior to alpha1-ARA therapy with their similar epithelial and stromal apoptotic effects with unaffected cell proliferation.

International Journal of Impotence Research, 1999

Peyronie’s patients are candidates for surgical treatment when the acute phase has resolved. The ... more Peyronie’s patients are candidates for surgical treatment when the acute phase has resolved. The choice of surgical treatment modality, either reconstructive procedure or implantation of penile prosthesis, largely depends on the type and degree of the deformity and the penile vascular status of the patient. We present the results of ou1 Effects of inhibitors and rmTNF-α on FMLP-induced O2 production

Urology, 2001

Objectives. Honeymoon impotence is the inability to perform successful sexual intercourse during ... more Objectives. Honeymoon impotence is the inability to perform successful sexual intercourse during the initial experience, especially during the first nights of marriage, and it is relatively frequent in Turkey. We investigated the underlying penile vascular abnormalities in patients presenting with honeymoon impotence and sought to differentiate between psychogenic and organic etiologies. Methods. Between 1989 and 1999, 90 patients sought urologic help for honeymoon impotence. Patient age ranged from 18 to 39 years (mean 28.06 Ϯ 3.4). All patients were given an intracavernous injection of 60 mg papaverine combined with self-manual genital stimulation (CIS test) to assess the degree of tumescence. Patients with a positive response to the CIS test were later evaluated with nocturnal penile tumescence (NPT) monitoring. Patients with a negative response to the CIS test and/or NPT monitoring were evaluated further using penile color Doppler ultrasound. Results. A psychogenic etiology was found in 61 patients (67.7%), 50 (55.5%) of whom achieved satisfactory sexual intercourse after intracavernous injection. Twenty-five patients (27.7%) exhibited penile vascular abnormalities by color Doppler ultrasound. Neurogenic erectile dysfunction was considered in the remaining 4 patients (4.4%) with a positive response to the CIS test, abnormal findings on NPT monitoring, and a normal vascular system with color Doppler ultrasound. Conclusions. The present study is the first to report penile vascular abnormalities in patients presenting with honeymoon impotence, which was previously believed to be exclusively psychogenic in origin. The evaluation of the penile vascular system in patients with honeymoon impotence may reveal underlying penile vascular abnormalities, allowing the choice of the appropriate therapeutic option. UROLOGY 57: 758-762, 2001.

Proceedings of The National Academy of Sciences, 2004

Significant impairment in endothelial-derived nitric oxide is present in the diabetic corpus cave... more Significant impairment in endothelial-derived nitric oxide is present in the diabetic corpus cavernosum. RhoARho-kinase may suppress endothelial nitric oxide synthase (eNOS). Here, we tested the hypothesis that RhoARho-kinase contributes to diabetes- related erectile dysfunction and down-regulation of eNOS in the streptozotocin (STZ)-diabetic rat penis. Colocalization of Rho- kinase and eNOS protein was present in the endothelium of the corpus cavernosum.

Transplantation Proceedings, 2002

described recently was first detected in peripheral blood and liver tissue of symptomatic patient... more described recently was first detected in peripheral blood and liver tissue of symptomatic patients with posttransfusion hepatitis non A-G. 1,2 TTV is presumed to be an unenveloped, circular, negative stranded DNA virus containing a genome of 3852 bases. It is proposed that TTV is a member of a new virus family that infects humans, tentatively named the Circinoviridae. TTV infection in humans occurs worldwide, and its prevalence is regionally very different. 4 It was first isolated from patients with posttransfusion hepatitis. 2 Viremia may be transient or persistent, and viremic individuals are often asymptomatic. Its transmission occurs not only by blood transfusion, but also by non-parenteral infection. 5 Renal transplant (RTx) recipients can be infected with TTV because of exposure to the frequent blood transfusions during hemodialysis treatments. However, not much data is available about TTV infection in renal transplant recipients. 6,7 Therefore, we investigated the prevalence of TTV and the relation to liver diseases in these populations.

Journal of Internal Medicine, 2003

Usta M, Ersoy A, Dilek K, Ö zdemir B, Yavuz M, Gü llü lü M, Yurtkuran M (Uludag University Medica... more Usta M, Ersoy A, Dilek K, Ö zdemir B, Yavuz M, Gü llü lü M, Yurtkuran M (Uludag University Medical School, Bursa, Turkey). Efficacy of losartan in patients with primary focal segmental glomerulosclerosis resistant to immunosuppressive treatment. J Intern Med 2003; 253: 329-334.

International Urology and Nephrology, 2000

Nitric oxide (NO) has been reported to be increased in the spermatic veins of men affected by var... more Nitric oxide (NO) has been reported to be increased in the spermatic veins of men affected by varicocele. The aim of the present study was to determine whether iNOS (inducible nitric oxide synthase) has a role in testicular dysfunction associated with varicocele, immunohistochemistry analyze was used to study iNOS activity in testis of adolescent rats with experimental left varicoceles. Rats were randomly divided into three groups. The first group consisted of rats undergoing partial ligation of left renal vein (n:12). The second group consisted of rats undergoing a sham operation (n:6) and, the third group referred to as control rats (n:7). Immunohistochemistry slides were evaluated by counting the number of positive cells and expressed as percents (% iNOS activity). We found that iNOS was predominantly expressed in the cytoplasm of Leydig cells in each group and only a small amount of iNOS was expressed in Sertoli cells. There were significant differences in % iNOS activity between both testes of varicocele group and both of testes control group (p < 0.01), but no significant differences were noted between other groups (p > 0.05). Because of iNOS activity was markedly increased in the Leydig cells of varicocele bearing rats, we suggest that iNOS activity may play a role in the testicular dysfunction associated with varicocele during adolescence.