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91.
Oguz Gozen Burcu Balkan Emre Yildirim Ersin O. Koylu Sakire Pogun 《Synapse (New York, N.Y.)》2013,67(9):545-552
Nicotine is a highly addictive drug and exerts its effect partially through causing dopamine release, thereby increasing intrasynaptic dopamine levels in the brain reward systems. Dopaine D1 receptor (DRD1) mRNAs and receptors are localized in reward‐related brain regions, which receive cholinergic input. The aim of this study is to evaluate whether nicotine administration affects the expression of DRD1s, and if so, whether epigenetic mechanisms, such as histone acetylation, are involved. Twenty Male Sprague Dawley rats received nicotine (0.4 mg/kg/day, s.c.) or saline injections for 15 days. After nicotine/saline treatment, rats were perfused with saline; prefrontal cortex (PFC), corpus striatum (STR), and ventral tegmental area (VTA) were dissected. Homogenates were divided into two parts for total RNA isolation and histone H4 acetylation studies. DRD1 mRNA expression was significantly higher in the PFC of the nicotine‐treated group compared with controls; similar trends were observed in the VTA and STR. To study epigenetic regulation, the 2kb upstream region of the DRD1 gene promoter was investigated for histone H4 acetylation in PFC samples. After chromatin immunoprecipitation with anti‐acetyl histone H4 antibody, we found an increase in histone acetylation by two different primer pairs which amplified the ?1365 to ?1202 (P < 0.005) and ?170 to +12 (P < 0.05) upstream regions of the DRD1 promoter. Our results suggest that intermittent subcutaneous nicotine administration increases the expression of DRD1 mRNA in the PFC of rats, and this increase may be due to changes in histone H4 acetylation of the 2kb promoter of the DRD1 gene. Synapse 67:545–552, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
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Berna Akkus Yildirim Yemliha Dolek Ozan Cem Guler Gungor Arslan Cem Onal 《Medical Dosimetry》2019,44(4):332-338
We performed this dosimetric study to compare a nonstandard volumetric modulated arc therapy (VMAT) and helical tomotherapy (HT) techniques with high-dose rate (HDR) brachytherapy (BRT) plan of vaginal vault in patients with postoperative endometrial cancer (EC). Twelve postoperative patients with early stage EC were included in this study. Three plans were performed for each patient; dosimetric and radiobiological comparisons were made using dose-volume histograms and equivalent dose for determining the planning target volume (PTV) coverages in brachytherapy and external beam radiotherapy, and organs-at-risk (OARs) doses between three different delivery techniques. All the plans achieved adequate dose coverage for PTV; however, the VMAT plan yielded better dose conformity, and the HT plan showed better homogeneity for target volume. With respect to the OARs, the bladder D2cc was significantly lower in the BRT plan than in the VMAT and HT plans, with the highest bladder D2cc value being observed in the HT plan. However, no difference was observed in the rectum D2cc of the three plans. Other major advantages of the BRT plan over the VMAT and HT plans were the relatively lower body integral doses and femoral head doses as well as the fact that the integral doses were significantly lower in the BRT plan than in the VMAT and HT plans. This is the first dosimetric comparison of vaginal vault treatment for EC with BRT, VMAT, and HT plans. Our analyses showed the feasibility of stereotactic body radiotherapy technique as an alternative to HDR-BRT for postoperative management of EC patients. 相似文献
94.
Kidney transplantation for end‐stage renal disease secondary to familial Mediterranean fever
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Mahmut Altindal Ercan Turkmen Tolga Yildirim Rahmi Yilmaz Fazil Tuncay Aki Mustafa Arici Bulent Altun Yunus Erdem 《Clinical transplantation》2016,30(7):787-790
Although kidney transplantation (KT) is widely used for treating renal amyloidosis secondary to familial Mediterranean fever (FMF), data concerning transplant outcome are limited and inconsistent. The aim of this study was to determine the long‐term outcome of KT in patients with amyloidosis secondary to FMF. Kidney transplantation outcome in 24 patients with FMF was compared to that in 72 controls matched for age, gender of recipient, and type of the donor that underwent KT due to end‐stage renal disease (ESRD) not caused by FMF. Mean follow‐up time was 80.3 ± 55.1 months in the FMF group, vs. 86.5 ± 47.6 months in the control group. Death‐censored graft survival at five and 10 yr in the FMF group was 95.8% and 78.4%, respectively, and was comparable to that in the control group. In the FMF group, five‐ and 10‐yr patient survival (87.5 and 65.6%) was shorter than in the control group, but the difference was not statistically significant. The findings show that long‐term outcome of KT in the patients with amyloidosis secondary to FMF was comparable to that in patients with ESRD not caused by FMF. Recurrence of amyloidosis in the allograft, gastrointestinal intolerance, and fatal infections remain as major complications during the post‐transplant period. 相似文献
95.
Ebru Gok Oguz Guner Karaveli Gursoy Ozlem Yayar Tolga Yildirim Tolga Cimen Cengiz Bulut 《Renal failure》2016,38(8):1180-1186
Introduction: Left ventricular hypertrophy (LVH) is one of the most common cardiac abnormalities in patients with end stage renal disease (ESRD). Hypertension, diabetes, increased body mass index, gender, age, anemia, and hyperparathyroidism have been described as risk factors for LVH in patients on dialysis. However, there may be other risk factors which have not been described yet. Recent studies show that renalase is associated with cardiovascular events. The aim of this study was to reveal the relation between renalase, LVH in patients under hemodialysis (HD) treatment.Methods: The study included 50?HD patients and 35 healthy controls. Serum renalase levels and left ventricle mass index (LVMI) were measured in all participants and the relation between these variables was examined.Findings: LVMI was positively correlated with dialysis vintage and C-reactive protein (CRP) (r?=?0.387, p?=?0.005 and r?=?0.597, p?0.001, respectively) and was negatively correlated with residual diuresis and hemoglobin levels (r?=??0.324, p?=?0.022 and r?=??0.499, p?0.001, respectively). There was no significant association of renalase with LVMI in the HD patients (r?=?0.263, p?=?0.065). Serum renalase levels were significantly higher in HD patients (212?±?127?ng/mL) compared to controls (116?±?67?ng/mL) (p?0.001). Renalase was positively correlated with serum creatinine and dialysis vintage (r?=?0.677, p?0.001 and r?=?0.625, p?0.001, respectively).Discussion: In our study, LVMI was correlated with dialysis vintage, residual diuresis, CRP, and hemoglobin. LVMI tends to correlate with renalase and this correlation may be significant in studies with more patient numbers. The main parameters affecting renalase levels are dialysis vintage and serum creatinine. 相似文献
96.
Zuhal Kalay Ali Islek Mesut Parlak Ahmet Kirecci Ozgur Guney Esad Koklu 《The journal of maternal-fetal & neonatal medicine》2016,29(1):60-63
Background: Diagnosing cobalamin deficiency is critical, given the high prevalence of cobalamin deficiency particularly in developing countries. Measuring serum cobalamin levels is of limited diagnostic sensitivity, in other words its specificity and sensitivity are low. The present study investigated the changes in the levels of metabolic markers – plasma homocysteine, plasma methylmalonic acid (MMA) and urinary MMA – of cobalamin metabolism.Methods: Plasma cobalamin and serum folic acid were studied in 206 pregnant women over the last four prenatal weeks. Plasma cobalamin, folic acid, homocysteine, MMA from umbilical cord blood and urinary MMA in newborns were studied.Results: Plasma cobalamin values were low in 66% of the mothers. There was a positive correlation between maternal and neonatal plasma cobalamin values (r?=?0.72, p?<?0.001). B12 was strongly inversely associated with plasma MMA, urine MMA and plasma homocysteine. To predict cobalamin deficiency, sensitivities of plasma MMA, urinary MMA and homocysteine were 96.4%, 95.6% and 88.2%, respectively. And positive predictive values (PPV) were 96.2%, 96.9% and 86% for plasma MMA, urinary MMA and plasma homocysteine levels, respectively.Conclusion: Plasma MMA and urinary MMA B12 are the most robust markers of cobalamin deficiency. As a non-invasive method, urinary MMA is a sensitive method in demonstrating cobalamin deficiency in the newborn. 相似文献
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Fatih Mehmet Kandemir Cuneyt Caglayan Emrah Hicazi Aksu Serkan Yildirim Sefa Kucukler Cihan Gur Gizem Eser 《Andrologia》2020,52(3):e13524
This study investigated the effects of rutin against reproductive damage caused by toxic mercury in male rats. Thirty-five Sprague Dawley rats were used. Control group was injected with saline for 7 days. The rutin-100 group received 100 mg/kg/b.w. rutin for 7 days. Mercuric chloride (HgCl2) group received 1.23 mg/kg/b.w. of HgCl2 for 7 days. Mercury chloride + rutin-50 group received 50 mg/kg/b.w. rutin and HgCl2 1.23 mg/kg/b.w. for 7 days. HgCl2 + rutin-100 group received 100 mg/kg/b.w. rutin and HgCl2 1.23 mg/kg/b.w. for 7 days. It was detected that HgCl2 treatment increased malondialdehyde (MDA) levels, tumour necrosis factor-α (TNF-α) and cyclooxygenase-2 (COX-2) expressions, necrosis and degeneration of spermatogonium, dead and abnormal sperm percentages; tubular walls thinning; and decreased antioxidant enzyme activities and sperm motility. It was determined that rutin application reduced testicular damage caused by HgCl2. In conclusion, rutin administration may treat HgCl2 toxicity in testes. 相似文献
99.
Zuhal Karagoz Genc Sibel Selcuk Suleyman Sandal Naki Colak Serhat Keser Memet Sekerci Mustafa Karatepe 《Medicinal chemistry research》2014,23(5):2476-2485
Novel six Cu(II), Ni(II), and Zn(II) complexes with Schiff bases derived from 4-aminobenzoic acid with terephtaldehyde and amino acids (glycine, β-alanine). Structures have been proposed from elemental analysis, UV–Vis, IR, NMR, TGA, DTA, and magnetic measurements. Spectroscopic studies suggest that coordination occurs through azomethine nitrogen, hydroxyl group, and carbonyl oxygen of the ligands to the metal ions. The elemental analyses of the complexes where L is Schiff base ligands, are confined to the stoichiometry of the type M2L2(CH3COO)2 [M = Cu(II)]; and M2L(CH3COO)2 [M = Ni(II) and Zn(II)]. The cytotoxicity activities of the compounds against human breast carcinoma MCF-7 cell line have been studied. Ligands and their Zn(II) compounds inhibited cell proliferation of MCF-7 cancer cell lines in a dose- and time-dependent manner. The free radical scavenging activity was measured by 1,1-diphenyl-2-picryl-hydrazil. Our results show that the synthesized compounds induced oxidative damage by increasing the lipid peroxidation in yeast since MDA formation was increased, and it could be concluded that the synthesized compounds caused oxidative stress. In addition, the antioxidant activities of the synthesized compounds were very much lower than those of standard antioxidants. 相似文献
100.