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1.
Feza Karakayali Nihan Haberal Hale Tufan Nesrin Hasirci Ozgur Basaran Sinasi Sevmis Aydin Akdur Aysel Kiziltay Mehmet Haberal 《Journal of investigative surgery》2007,20(3):167-173
Tranilast is an antiallergic drug that interferes with proliferation and migration of vascular smooth muscle cell induced by platelet-derived growth factor (PDGF) and transforming growth factor-beta1 (TGF-beta1). We investigated the local effect of tranilast on neointimal hyperplasia using tranilast-coated prosthetic grafts. The inner sides of the thin-walled polytetrafluoroethylene (PTFE) grafts were coated with chitosan and tranilast containing chitosan solution. Wistar albino rats (32) were used in the study. Patches (1 x 2 mm) for vascular grafts were prepared. Three groups were tested: group 1 (n = 12; tranilast coated), group 2 (n = 10; adhesive-only film-layer-coated), and group 3 (n = 10; normal ePTFE patch grafts sutured to the carotid arteries of the rats). Recipient sites of the carotid arteries were excised 4 weeks after surgery. All sections were examined histologically for graft patency, thrombus formation, and neointimal thickness. Expression of PDGF, fibroblast growth factor, and TGF-beta1 on cross-sections of the neointima were evaluated by immunohistochemistry. No significant differences were found regarding mean neointimal thicknesses. PDGF and TGF-beta-1 expressions were significantly lower in group 1. Although a decrease in local effect of tranilast was observed for growth factor expressions at a drug concentration of 0.05 mg/cm(2), a significant reduction in neointimal hyperplasia was not achieved. The coating concentration of 0.05 mg/cm(2) may have been too low to produce an antiproliferative effect. Given our promising results, further studies are recommended and planned using different drug concentrations and time intervals. 相似文献
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Mete Isikoglu Kemal Ozgur Sergio Oehninger Sebahat Ozdem Murat Seleker 《Gynecological endocrinology》2006,22(5):256-260
BACKGROUND: We aimed to determine whether serum concentrations of anti-Müllerian hormone (AMH) can be used as a tool for prediction of the efficacy of sperm retrieval. METHODS: This was a prospective cohort observational study. AMH levels were determined in 47 men presenting for infertility evaluation. Group 1 consisted of 24 infertile patients diagnosed with non-obstructive azoospermia. Group 1 was further divided into two subgroups. The patients with spermatozoa in their testicular samples constituted group 1a (n = 13), while the patients with absence of spermatozoa constituted group 1b (n = 11). Twenty-three normozoospermic fertile men constituted group 2. Serum AMH was measured before obtaining testicular specimens. RESULTS: Testicular spermatozoa were recovered in 13 out of the 24 patients (54%). Demographic characteristics of the three groups were similar. The difference between serum AMH levels among the three groups did not reach statistical significance. CONCLUSIONS: We speculated that although AMH is secreted predominantly into the seminiferous tubules, studying serum samples might be more advantageous than seminal plasma because the presence of seminal proteases could influence AMH levels in the latter. However, our results did not demonstrate differences in serum concentrations of AMH between the studied groups. Studies with extended patient populations focusing on seminal plasma concentrations of AMH are warranted. 相似文献
4.
Gursel Dursun Ozan Bagis Ozgursoy Ozgur Kemal Isil Coruh 《European archives of oto-rhino-laryngology》2007,264(9):1027-1032
The purpose of this study was to present our experience with combined use of CO2 laser and cold instrumentation for Reinke’s edema surgery and to evaluate 1-year follow-up results of the technique in a
series of professional voice users. Fifteen patients with Reinke’s edema who underwent microlaryngoscopic surgery were included.
Videolaryngostroboscopy, perceptual and acoustic voice analyses were performed before and after surgery. During the 1-year
follow-up, no recurrence of Reinke’s edema was encountered. Significant postoperative improvement was obtained in the quality
of voice, in terms of GRBAS scores, Fo, jitter, shimmer and NHR. No evidence of laryngeal cancer was found on the histological
examinations. Combined use of CO2 laser and cold instrumentation provides a reliable and safe method for Reinke’s edema surgery, and cessation of smoking,
voice rest and control of the laryngopharyngeal reflux contribute to the success of surgery. We consider that the removal
of redundant mucosa of the vocal fold reduces the risk of the recurrence of Reinke’s edema and provides better quality of
voice. However, it does not imply that our method is superior to others’, but this procedure constitutes an effective treatment
of choice for Reinke’s edema patients, including professional voice users. 相似文献
5.
Ozgur O; Boyacioglu S; Ozdogan M; Gur G; Telatar H; Haberal M 《Nephrology, dialysis, transplantation》1997,12(2):289-291
Background. It is known that Helicobacter
pylori (Hp) plays an important role in gastritis and peptic
ulcer disease in the general population. Although dyspeptic complaints are
frequent in haemodialysis (HD) patients and renal transplant recipients,
there are few reports regarding the prevalence of Hp and its possible
effects on this group of patients. This study was performed to examine the
prevalence of Hp infection in patients on regular HD treatment and to
detect its role in the pathogenesis of dyspepsia in this group of patients.
Methods. Two hundred and one patients with dyspeptic
complaints were included in the study. The groups consisted of 47 HD, 54
renal transplant recipients, and 100 non-renal disease patients. Upper
gastrointestinal endoscopies were performed and gastric antral biopsies
were obtained for urease test in all patients.
Results. Twenty-eight (60%) of the 47 HD and 28 (70%)
of the 54 RTR were positive for Hp. Sixty-four (64%) of the 100 patients
with various gastrointestinal complaints and known to have no renal
dysfunction were positive for Hp. The Hp prevalences among the three groups
were not significantly different (P <0.05). The prevalence of Hp
infection did not correlate with the haemodialysis duration nor the
post-transplantation duration (P <0.05). There was no correlation
between the prevalence of Hp infection and duration of haemodialysis
therapy or time post-transplantation. Conclusion.
These findings suggest that HD patients are not protected against Hp
infection as the Hp prevalences are as high as that for the non-renal
disease group. The increased dyspeptic complaints may be partly related to
Hp infection. 相似文献
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8.
To compare morphological changes in the umbilical cords from chronic hypertensive and preeclamptic patients having normal or pathological umbilical artery Doppler ultrasonographic results. Umbilical cords from 34 normotensive, 31 chronic hypertensive and 70 preeclamptic women with normal and abnormal Doppler flow velocity waveforms (FVW) at 35-40 gestational weeks were studied. Morphological changes in the umbilical cords were examined on formalin-fixed, paraffin-embedded sections. The total umbilical cord area, total vessel area, and wall thickness of umbilical vessels were measured in systematic random samples using unbiased stereology methods. An ANOVA test was used for statistical analysis. In the chronic hypertensive and preeclamptic groups with normal Doppler FVW, the thickness of the umbilical cord vessels remained nearly constant, whereas both the total area and the lumen area were reduced. These changes correlate with the histopathological findings, suggesting a mainly vasoconstrictive effect. By contrast, analysis of the preeclamptic group with pathologic Doppler FVW showed a comparable reduction of all parameters of the umbilical cord. Histopathological findings were related to smaller, contracted smooth muscle cells of the vessel wall, which is suggestive of a predominant hypoplastic mechanism. As a result of reduced uteroplacental perfusion, fetal hypoxia and intrauterine growth retardation become unavoidable in preeclampsia. The histopathological changes in the umbilical cord between the chronic hypertensive and preeclamptic patients depend on the Doppler results. In conclusion, the umbilical artery Doppler FVW indices provide good values for predicting intrauterine growth retardation in preeclamptic patients. 相似文献
9.
Direct evidence for the involvement of carbohydrate sequences in human sperm-zona pellucida binding 总被引:2,自引:0,他引:2
Several lines of evidence indicate that mammalian fertilization is
initiated via a binding process that is dependent upon the recognition of
oligosaccharide sequences associated with zona pellucida (ZP)
glycoproteins. Here, specific chemical and enzymatic methods were employed
to modify human ZP and to test their effects on sperm binding in the
hemizona assay system (HZA). Periodate oxidation of human ZP under very
mild conditions (10 min, 0 degrees C, 1 mM sodium m- periodate) that
attacks only terminal sialic acid resulted in a 30% loss of human sperm
binding in the HZA [hemizona index (HZI) = 70.2 +/- 10.9, n = 22; P <
0.05]. Periodate oxidation under mild conditions (1 h, 23 degrees C, 10 mM
sodium m-periodate) caused a 40% decrease in binding (HZI = 60.8 +/- 10.3;
n = 24; P< 0.01). Treatment of human ZP with neuraminidase caused a
substantial increase in sperm binding to human ZP (HZI = 297 +/- 45, n =
22; P < 0.01). These findings indicate that there are sialic acid
dependent binding sites coexisting with binding sites that are obscured by
sialic acid. To determine the periodate sensitivity of these obscured
sites, hemizona were first digested with neuraminidase and subsequently
subjected to mild periodate oxidation. The combined enzymatic and chemical
treatments caused a 79% decrease in sperm binding compared to control
hemizona (HZI = 20.7 +/- 4.4, n = 16; P < 0.001). Human sperm-ZP
interaction was also increased by digestion of human ZP with
endo-beta-galactosidase (HZI = 710 +/- 232, n = 14; P < 0.01),
indicating that potential binding sites for spermatozoa are also obscured
by lactosaminoglycan sequences. These studies support a definitive role for
the involvement of ZP-associated glycans in the binding of human
spermatozoa to oocytes.
相似文献
10.
Emrah Caliskan Salih Suha Koparal Volkan Igdir Emre Alp Ozgur Dogan 《Foot and Ankle Surgery》2021,27(4):457-462
BackgroundThe measurement of plantar fascia thickness with ultrasonography can be used for both for diagnosis and as a response-to-treatment parameter in plantar fasciitis. Furthermore, with the recent studies, red cell distribution width may be used as an inflammatory marker. Aim of this study is to investigate the association of red cell distribution width and ultrasonography on diagnosis and monitoring of treatment in patients with plantar fasciitis.MethodsClinically diagnosed 102 patients with plantar fasciitis between the dates January 2016 to July 2018 were analysed. Hemogram, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and plantar fascial ultrasonography were obtained on initial evaluation and in 1 month, 2 months and 3 months of the standard nonoperative treatment; American Orthopaedic Foot & Ankle Hindfoot Score (AOFAS) and Visual Analog Scale (VAS) scores were recorded. Posthoc and multivariate logistic regression analysis were used for statistical analysis on SPSS 21.0.ResultsRed cell distribution width was correlated with plantar fascia thickness by the end of the 1 month (r = 0.26, P = .013). Female sex, BMI over 30 kg/m2, higher red cell distribution width and higher plantar fascia thickness were associated with plantar fasciitis on initial evaluation. Higher red cell distribution width together with higher plantar fascia thickness were also found to be a risk factor for both on initial evaluation and 1 month after treatment in plantar fasciitis.ConclusionThis study shows that association of red cell distribution width and plantar fascia thickness can be not only a diagnostic predictor but also an indicator of treatment response in plantar fasciitis.Level of clinical evidenceLevel IV 相似文献