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91.
BACKGROUND/AIMS: To date direct toxic effects of free oxygen radicals in vivo on pancreatic parenchyma have not been studied thoroughly. We aimed to study: 1) the detailed histopathological changes induced by free oxygen radicals in pancreas; and 2) the preventive effect of intraductal catalase in H2O2-induced acute pancreatitis. METHODOLOGY: Wistar Albine rats were randomized into six groups. 1) First experiment: Bile-pancreatic duct was cannulated close to the liver and perfused through the duodenum with (i) normal saline solution, (ii) iron sulfate (FeSO4), (iii) hydrogen peroxide (H2O2), (iv) hydrogen peroxide and iron sulfate simultaneously. 2) Second experiment: Bile pancreatic duct was perfused either with H2O2 or H2O2 + catalase. Serum amylase and pancreas malondialdehyde levels were measured in both experiments after 3 hours of perfusion period. Tissue samples were obtained for histopathological examinations. RESULTS: 1) First experiment: Intraductal perfusion of FeSO4 or H2O2 or H2O2 + FeSO4 induced acute edematous pancreatitis with focal parenchymal necrosis. At the ultrastructural level, intracytoplasmic formation of vacuoles. fusion of the vacuoles and zymogen granules, and autophagosomes containing cellular organelles were found. Serum amylase and pancreas malondialdehyde levels, and morphological score were significantly higher in these groups than control group (p < 0.001). 2) Second experiment: Catalase perfusion simultaneously with H2O2 decreased the serum amylase and pancreas malondialdehyde levels, and morphological score significantly (p < 0.001) and prevented the desquamation of the columnar epithelium and development of gross edema but not parenchymal necrosis. CONCLUSIONS: Intraductal perfusion of FeSO4 or H2O2 or H2O2 + FeSO4-induced acute pancreatitis with marked light and electronmicroscopic changes. Intraductal perfusion of catalase and H2O2 simultaneously did not prevent or lessen the parenchymal necrosis. These findings have suggested that another mechanism of injury may also play a role in parenchymal injury in oxygen radical-induced acute pancreatitis. 相似文献
92.
Muhsin Kaya Şengül Baran Cemil Güya Mehmet Ali Kaplan 《Indian journal of gastroenterology》2016,35(3):201-206
Background and Aims
Splenic artery aneurysm (SAA) rarely occurs in the general population. Its increased incidence has been reported in cirrhosis. The aim of this retrospective study was to identify prevalence and predictive factor development of SAA in patients with cirrhosis.Methods
All patients with cirrhosis who were treated in our clinics between 2010 and 2014 were included in the study. Demographic features and clinical and laboratory findings were reviewed. Four-phase computerized tomography (CT) was used for identifying SAA. Imaging was reviewed for the presence of SAA as well as hepatic artery, portal vein, splenic artery, splenic vein, liver parenchyma, and intraabdominal cavity were evaluated.Results
A total of 171 patients (age 55±13.9, 109 men) were included in the study. There was SAA in 27 (15.7 %) patients. Mean diameter of aneurysm was 11.66 (range, 6.06–27.1) mm. Aneurysm was located in the distal part of splenic artery in 20 (74 %) patients and solitary in 24 (88.8 %), and asymptomatic in all patients. Patients with SAA had larger portal vein and splenic vein compared to patients without SAA (15.3±3.9 vs. 13.1±2.9 mm, p=0.001; and 12.5±4.4 vs. 9.6±2.7 mm, p<0.001, respectively). We identified positive correlation between development of SAA and splenic vein diameter [hazard ratio (HR)?=1.23; 95 % confidence interval (CI) 0.97–1.57; p = 0.009] and negative correlation between hepatic artery diameter and development of SAA HR?=?0.46; 95 % CI 0.25–0.85; p?=?0.002).Conclusion
SAA occurred in a significant proportion of patients with cirrhosis, and enlargement of the splenic vein seemed to be a predictive factor for the development of SAA.93.
Exome sequencing identifies a homozygous C5orf42 variant in a Turkish kindred with oral‐facial‐digital syndrome type VI 下载免费PDF全文
94.
Mustafa Y?ld?r?m Vildan Kaya ?zlem Demirpen?e Semra Payda? 《Archives of Medical Science》2015,11(4):708-714
Introduction
Diffuse large B cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin lymphoma (NHL). Although gender has not been included in prognostic systems, male gender has been found as a bad prognostic indicator in Hodgkin lymphoma, follicular lymphoma and chronic lymphocytic leukemia. The relationship between gender and prognosis is not clear in patients with DLBCL treated with rituximab-containing regimens. The aim of this meta-analysis is to determine the prognostic/predictive role of gender in patients with DLBCL treated with rituximab-containing regimens.Material and methods
We systematically searched for studies investigating the relationships between gender and prognosis in DLBCL treated with rituximab-containing regimens. After careful review, survival data were extracted from eligible studies. A meta-analysis was performed to generate combined hazard ratios for overall survival, disease-free survival (DFS) and event-free survival (EFS).Results
A total of 5635 patients from 20 studies were included in the analysis. Our results showed that male gender was associated with poor prognosis in terms of overall survival (OS) (hazard ratio (HR) = 1.155; 95% confidence interval (CI): 1.037–1.286; p < 0.009). The pooled hazard ratio for DFS and EFS showed that male gender was not statistically significant (HR = 1.219; 95% CI: 0.782–1.899; p = 0.382, HR = 0.809; 95% CI: 0.577–1.133; p = 0.217).Conclusions
The present meta-analysis indicated male gender to be associated with a poor prognosis in patients with DLBCL treated with rituximab-containing regimens. 相似文献95.
Nezih Akkapulu Mehmet Bulent Tirnaksiz Ibrahim Kulac Gaye Guler Tezel Mutlu Hayran Ahmet Bulent Dogrul Erdinc Cetinkaya Kaya Yorganci 《International journal of clinical and experimental pathology》2015,8(3):3230-3237
Intra-abdominal hypertension and abdominal compartment syndrome (IAH/ACS) are life-threatening conditions and caused by several clinical status. Although there is insufficient data regarding its effects on adrenal glands. This study aimed to identify whether elevated intra-abdominal pressure (IAP) caused any alteration on the morphology and function of adrenal glands in a rat model. Twenty four Sprague-Dawley male rats were included in the study. Animals were allocated into 4 groups. IAP was elevated to 15 mmHg for one hour and four hours in group 2 and 4. Group 1 and 3 were sham groups. Blood samples were taken for the assessment of plasma adrenaline, noradrenaline, and corticosterone levels and adrenalectomies were performed to evaluate apoptosis. Blood adrenaline, noradrenaline and corticosterone levels were significantly higher in the study groups compared with the sham groups. However, there were no significant changes in apoptotic index scores in the study groups as compared to sham groups. These results support that increased IAH leads to discharge of catecholamine and corticosterone from the adrenal glands. Failure to demonstrate similar changes in apoptotic index score may be concluded as apoptosis is not a leading pathway for impairment of adrenal glands during IAH period. 相似文献
96.
Muhammet Dural Giray Kabakcı Neşe Çınar Tomris Erbaş Uğur Canpolat Kadri Murat Gürses Lale Tokgözoğlu Ali Oto Ergün Barış Kaya Hikmet Yorgun Levent Şahiner Selçuk Dağdelen Kudret Aytemir 《Pituitary》2014,17(2):163-170
Cardiovascular complications are the most common causes of morbidity and mortality in acromegaly. However, there is little data regarding cardiac autonomic functions in these patients. Herein, we aimed to investigate several parameters of cardiac autonomic functions in patients with acromegaly compared to healthy subjects. We enrolled 20 newly diagnosed acromegalic patients (55 % female, age:45.7 ± 12.6 years) and 32 age- and gender-matched healthy subjects. All participants underwent 24 h Holter recording. Heart rate recovery (HRR) indices were calculated by subtracting 1st, 2nd and 3rd minute heart rates from maximal heart rate. All patients underwent heart rate variability (HRV) and QT dynamicity analysis. Baseline characteristics were similar except diabetes mellitus and hypertension among groups. Mean HRR1 (29.2 ± 12.3 vs 42.6 ± 6.5, p = 0.001), HRR2 (43.5 ± 15.6 vs 61.1 ± 10.8, p = 0.001) and HRR3 (46.4 ± 16.2 vs 65.8 ± 9.8, p = 0.001) values were significantly higher in control group. HRV parameters as, SDNN [standard deviation of all NN intervals] (p = 0.001), SDANN [SD of the 5 min mean RR intervals] (p = 0.001), RMSSD [root square of successive differences in RR interval] (p = 0.001), PNN50 [proportion of differences in successive NN intervals >50 ms] (p = 0.001) and high-frequency [HF] (p = 0.001) were significantly decreased in patients with acromegaly; but low frequency [LF] (p = 0.046) and LF/HF (p = 0.001) were significantly higher in acromegaly patients. QTec (p = 0.009), QTac/RR slope (p = 0.017) and QTec/RR slope (p = 0.01) were significantly higher in patients with acromegaly. Additionally, there were significant negative correlation of disease duration with HRR2, HRR3, SDNN, PNN50, RMSSD, variability index. Our study results suggest that cardiac autonomic functions are impaired in patients with acromegaly. Further large scale studies are needed to exhibit the prognostic significance of impaired autonomic functions in patients with acromegaly. 相似文献
97.
98.
99.
Mujgan T. Ozturk MD Bunyamin Yavuz MD Selcuk Ozkan MD Mehmet Ayturk MD Tolga Akkan MD Esin Ozkan MD Engin Tutkun MD Ömer H. Yılmaz MD 《Journal of clinical hypertension (Greenwich, Conn.)》2014,16(11):790-793
Arterial hypertension is one of the physical complications of chronic lead exposure. Hypertension has effects on aortic elastic properties. The aim of this study was to evaluate the aortic elastic properties in workers occupationally exposed to lead. Forty‐one workers who were exposed to lead and 39 healthy controls were included in the study. All patients underwent transthoracic echocardiography for detecting aortic elastic parameters. There were no differences in baseline characteristics between the lead‐exposure group and controls. Aortic strain (9.4%±4.5% vs 12.4%±4.2%, P=.004) and aortic distensibility (0.45±0.21 cm2/dyn vs 0.55±0.20 cm2/dyn, P=.046) were decreased in patients with lead exposure compared with controls. There was a negative significant weak correlation between aortic strain and (r=−0.294, P=.008) lead levels. There was no significant correlation between aortic distensibility and any other echocardiographic parameters. This study suggests that chronic exposure to lead is related to impairment of aortic elasticity parameters.Lead contamination (such as that emitted from house paint, gasoline, batteries, and other sources) may cause a wide variety of body organ complications.1 Despite the still manifested divergences of opinion, it seems that chronic exposure to lead represents a risk for arterial hypertension development. Functional changes within the arterial wall both in smooth muscles and the endothelium might result in arterial hypertension caused by chronic exposure to lead compounds.2 Blood pressure (BP) was found to be increased in workers with blood lead concentrations of 7 μg/L on average.3 According to the World Health Organization (2000), the level of 400 μg/L is accepted as safe to avoid possible adverse health effects, but American Conference Governmental and Industrial Hygienists suggest an even lower value of <300 μg/L.Hypertension has effects on the aorta (decreased aortic distensibility and increased aortic stiffness). Aortic strain is a simple and useful parameter of transthoracic echocardiography. Some studies have suggested that aortic elastic parameters can be used as an independent predictor of all‐cause and cardiovascular mortality in hypertensive patients.4, 5 In previous studies, the relationship between lead exposure and arterial hypertension has been demonstrated, and findings suggest that arterial hypertension and organ complications of arterial hypertension are more frequent in workers with lead exposure. Until now, there have been no data on the effects of lead exposure on aortic stiffness. The aim of this study was to evaluate the effects of lead on aortic elasticity parameters. 相似文献
100.
Lei Guo Youness El Bakri El Hassane Anouar Jianhong Tan Sava Kaya El Mokhtar Essassi 《RSC advances》2019,9(60):34761
Herein, the anti-corrosion of carbon steel in 1 M HCl by two newly synthesized pyrazolotriazole derivatives, namely, 6-methyl-1H-pyrazolo[5,1-c][1,2,4]triazole-7-carbonitrile (CPT) and 1-acetyl-6-methyl-1H-pyrazolo[5,1-c][1,2,4]triazole-7-carbothioamide (MPT), was studied using electrochemical, density functional theory (DFT), and molecular dynamics (MD) simulation techniques. The experimental results showed that the concentrations of inhibitors had a significant influence on their inhibition efficiencies. Potentiodynamic polarization curves indicated that the two pyrazolotriazoles were mixed-type inhibitors. DFT calculations were employed to explore the molecular activity, and MD simulations were performed to obtain the interaction energy between the inhibitor molecules and the iron surface. The findings obtained using the theoretical calculation techniques were consistent with those obtained via experiments.Anti-corrosion of carbon steel in 1 M HCl by 6-methyl-1H-pyrazolo[5,1-c][1,2,4]triazole-7-carbonitrile and 1-acetyl-6-methyl-1H-pyrazolo[5,1-c][1,2,4]triazole-7-carbothioamide, was studied using electrochemical, DFT and molecular dynamics simulation techniques. 相似文献