The epigenetic effect of nicotine on dopamine D1 receptor expression in rat prefrontal cortex

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.     

Increased serum renalase in hemodialysis patients: is it related to left ventricular hypertrophy?

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?r?=??0.324, p?=?0.022 and r?=??0.499, p?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?r?=?0.677, p?r?=?0.625, p?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.     

Maxillary sinus lipoma: an unanticipated diagnosis

Subcutaneous tissue gives rise to numerous lesions such as lipoma, the most common benign soft tissue tumors. Lipoma is seen only extremely rarely in osseous units. In addition, craniofacial involvement of intraosseous lipoma may be misdiagnosed as a fibroosseous tumour such as fibrous dysplasia. Here, we present a case of an intraosseous lipoma obviously destroying and invading the maxillary bone.     

Comparison of the proliferative activity in gingival epithelium after surgical treatments of intrabony defects with bioactive glass and bioabsorbable membrane

Guided tissue regeneration is based on preventing the more rapidly proliferating epithelium from growing into the periodontal defect after surgical procedures incorporating barrier membranes. The aim of this study was to compare the proliferative activity of gingival epithelium using proliferating cell nuclear antigen (PCNA) as a marker of cell proliferation after surgical treatments with bioactive glass graft material and bioabsorbable membrane. Using split mouth design, 20 intrabony defects were randomly assigned treatments with bioactive glass (BG group) or bioabsorbable membrane (BM group). Gingival biopsies were taken at preoperative and postoperative 12 weeks. After histological processing, the number of the inflammatory cells was measured in hematoxylin and eosin-stained sections; PCNA expression was determined in immunohistochemically-stained sections. At postoperative 12 weeks, the number of the inflammatory cells was significantly decreased (p < 0.01), PCNA expression was significantly increased (p < 0.001) in both treatment groups compared to baseline data. There was no significant difference in PCNA expression between baseline values of two groups (p > 0.05), while at postoperative 12 weeks, increase in BG group was significantly greater than that in BM group (p < 0.001). These results suggest that epithelial cell proliferation is more prominent after treatment of intrabony defects with bioactive glass compared to the treatment with bioabsorbable membrane.     

An evaluation of the role of tumor load in cytoreductive nephrectomy

IntroductionNew radiological tools can accurately provide preoperative three-dimensional spatial assessment of metastatic renal cell carcinoma (RCC). We aimed to determine whether the distribution, volume, shape, and fraction of RCC resected in a cytoreductive nephrectomy associates with survival.MethodsWe retrospectively reviewed 560 patients undergoing cytoreductive nephrectomy, performing a comprehensive volumetric analysis in eligible patients of all detectable primary and metastatic RCC prior to surgery. We used Cox regression analysis to determine the association between the volume, shape, fraction resected, and distribution of RCC and overall survival (OS).ResultsThere were 62 patients eligible for volumetric analysis, with similar baseline characteristics to the entire cohort, and median survivor followup was 34 months. Larger primary tumors were less spherical, but not associated with different metastatic patterns. Increased primary tumor volume and tumor size, but not the fraction of tumor resected, were associated with inferior survival. The rank of tumors based on unidimensional size did not completely correspond to the rank by primary tumor volume, however, both measurements yielded similar concordance for predicted OS. Larger tumor volume was not associated with a longer postoperative time off treatment.ConclusionsPrimary tumor volume was significant for predicting OS, while the fraction of disease resected did not appear to impact patient outcomes. Although rich in detail, our study is potentially limited by selection bias. Future temporal studies may help elucidate whether the primary tumor shape is associated with tumor growth kinetics.     

Carotid Artery Doppler Flow Pattern After Deep Hypothermic Circulatory Arrest in Neonatal Piglets

The mechanisms of cerebral injury after cardiac surgery in neonates are not clear. The aim of the study was the analysis of flow changes in the carotid artery of neonatal piglets after deep hypothermic circulatory arrest (DHCA). Eight neonatal piglets were connected to cardiopulmonary bypass (CPB) and underwent (i) cooling to 18°C core temperature within 30 min, (ii) DHCA for 90 min, and finally (iii) rewarming to 37°C after cross‐clamp release (60 min of reperfusion). The blood flow was measured in the left carotid artery by an ultrasonic flow probe before CPB (baseline; T₀), immediately after termination of reperfusion on CPB (T₁), 30 min later (T₂), and 60 min later (T₃). Additionally, the pulsatility index and the resistance index were calculated and compared. Finally, the relationship between the carotid artery flow and the corresponding pressure at each time‐point was compared. After termination of CPB (T₁), the mean carotid artery flow was reduced from 45.26 ± 2.58 mL/min at baseline to 23.29 ± 2.58 mL/min (P < 0.001) and remained reduced 30 and 60 min later (P < 0.001 vs. baseline). Both the pulsatility index and the resistance index were increased after termination of reperfusion, with the maximum occurring 30 min after CPB end. In conclusion, the carotid artery Doppler flow in neonatal piglets was reduced after DHCA, while the indices of pulsatility and resistance increased.