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61.
Leyla Guler Murat Tavlasoglu Orhan Yucel Adem Guler Mehmet Ali Sahin Mustafa Kurkluoglu Yusuf Sirin Ayse Eken Mehmet Gamsizkan Mehmet Dakak Sedat Gurkok Onur Genc 《Journal of anesthesia》2014,28(3):347-353
Purpose
Taurine, the major intracellular free amino acid found in high concentrations in mammalian cells, is known to be an endogenous antioxidant and a membrane-stabilizing agent. It was hypothesized that taurine may be effective in reducing ischemia–reperfusion injury after lung transplantation and an experimental study was conducted in a rat model.Methods
The number of Sprague–Dawley rats used in the study was 35. Animals were randomized into five groups of 7 rats each, including control, donor I, donor II, ischemia–reperfusion injury, and treatment groups. All animals were exposed to the same experimental conditions in the preoperative period. Rats were fixed in a supine position after the induction. After the rats were shaved, a left pneumonectomy was performed following sternotomy in control, donor I, and donor II groups. The harvested grafts in donor I and donor II groups were transplanted to the rats of the ischemia–reperfusion group and treatment group, respectively. However, taurine was administered intraperitoneally for 3 days before the harvesting procedure in donor II. All harvested lungs were kept in a Euro-Collins solution at +4 °C for 24 h in a half-inflated manner. After harvesting and transplantation, lungs were sampled for histopathological and biochemical analysis.Results
Malondialdehyde and superoxide dismutase, glutathione peroxidase, and catalase levels were lower in the treatment group than the other groups (p < 0.05). Histopathological findings were better in treatment group than the ischemia–reperfusion group (p < 0.05).Conclusion
It was demonstrated that donor treatment with taurine resulted in preservation of transplanted lung tissue in respect to histopathological and biochemical findings. 相似文献62.
Hurmus Gursu Yamur Guner Melih Besir Arvas Kamil Burak Dermenci Umut Savaci Metin Gencten Servet Turan Yucel Sahin 《RSC advances》2021,11(63):40059
In this study, the one-step electrochemical preparation of chlorine doped and chlorine-oxygen containing functional group doped graphene-based powders was carried out by Yucel''s method, with the resultant materials used as anode materials for lithium (Li)-ion batteries. Cl atoms and ClOx (x = 2, 3 or 4) groups, confirmed by X-ray photoelectron spectroscopy analysis, were covalently doped into the graphene powder network to increase the defect density in the graphene framework and improve the electrochemical performance of Li-ion batteries. The microscopic properties of the Cl-doped graphene powder were investigated by scanning electron microscopy and transmission electron microscopy (TEM) analyses. TEM analysis showed that the one-layer thickness of the graphene was approximately 0.33 nm. Raman spectroscopy analysis was carried out to determine the defect density of the graphene structures. The G peak obtained in the Raman spectra is related to the formation of sp2 hybridized carbons in the graphene-based powders. The 2D peak seen in the spectra shows that the synthesized graphene-based powders have optically transparent structures. In addition, the number of sp2 hybridized carbon rings was calculated to be 22, 19, and 38 for the Cl-GP1, Cl-GP2, and Cl-GOP samples, respectively. As a result of the charge/discharge tests of the electrodes as anodes in Li-ion batteries, Cl-GP2 exhibits the best electrochemical performance of 493 mA h g−1 at a charge/discharge current density of 50 mA g−1.In this study, the one-step electrochemical preparation of chlorine doped and chlorine-oxygen containing functional group doped graphene-based powders was carried out by Yucel''s method, with the resultant materials used as anode materials for lithium (Li)-ion batteries. 相似文献
63.
Cuneyt Tayman Ufuk Cakir Cigdem Yucel Buse Ozer Bekmez 《Archivos de bronconeumologia》2019,55(9):465-471
IntroductionEndocan levels were found to be associated with severity and mortality of the respiratory system diseases.ObjectiveWe aimed to figure out whether endocan was an important marker for the diagnosis, severity and follow-up of bronchopulmonary dysplasia (BPD).Materials and methodsInfants with moderate/severe BPD, and who required hydrocortisone treatment were included in the study group. Infants without BPD were allocated in the control group. Endocan levels were compared between the control group and the study group, and before and after the treatment in the study group.ResultsA total of 148 infants, 74 infants in the control group and 74 infants in the BPD group, were included. The endocan level was higher in the BPD group than in the control group (P = .001). Endocan levels before treatment in the BPD group was found to be higher than endocan level after treatment (P = .021).ConclusionOur study found that endocan levels increased in moderate/severe BPD. Serum endocan levels may be a safe and novel indicator for the follow-up of response to treatment and the prognosis of the severity of the disease. 相似文献
64.
Coronary lesion type, location, and characteristics of acute ST elevation myocardial infarction in young adults under 35 years of age 总被引:1,自引:0,他引:1
OBJECTIVE: In the present study, we attempted to analyze the coronary artery lesion characteristics of acute ST elevation myocardial infarction (STEMI) in young patients (aged less than 35 years). METHODS: We retrospectively surveyed 25 038 coronary angiography procedures, which were carried out at The Baskent University Adana Hospital from 1998 to present, to discover acute STEMI in young patients. We studied clinical risk factors and angiographic characteristics in 42 consecutive patients who underwent primary coronary angiography for acute STEMI. Control group (n=42) had no history of coronary artery disease and had angiographically proven normal coronary arteries. All patients were under 35 years of age. Angiographic features for STEMI group were collected and both groups were compared for coronary risk factors. RESULTS: Male sex was more prevalent in acute STEMI group when compared with control participants (83 vs. 59%, respectively; P=0.01). A significant difference was found in cigarette smoking (62 vs. 36%, respectively; P=0.007) and family history (33 vs. 16%, respectively; P=0.03) between the two groups. No statistical significance was observed between the groups in terms of hypertension, diabetes mellitus, total cholesterol, low-density lipoprotein cholesterol, and triglyceride levels. Mean high-density lipoprotein cholesterol level was 33+/-8 mg/dl in STEMI group and 39+/-12 mg/dl in control participants (P=0.02). Young patients with acute STEMI showed a preponderance of single-vessel disease (69%) and acute anterior STEMI (60%) owing to occluded left anterior descending artery (P<0.001). CONCLUSION: We observed risk factors such as family history, smoking, and low high-density lipoprotein cholesterol levels in young adults. Acute anterior STEMI owing to occluded left anterior descending artery was more frequent. Coronary atherosclerosis was characterized by higher presence of type B and proximal lesions. The handling selection was percutaneous coronary intervention in more than half of the patients. 相似文献
65.
The potential early predictive value of microalbuminuria (MA) in the estimation of atherosclerosis and the relation between the degree of urinary albumin excretion and the extent of coronary artery disease (CAD) were investigated. Patients (n = 159) with stable angina pectoris and angiographically significant stenosis in at least 1 of the major coronary arteries were included. Microalbuminuria was measured by immunoturbidimetry. The extent of coronary artery stenosis was graded using the Gensini score. The Gensini score was significantly greater in patients who had MA. Also, the Gensini increased by 0.15 units with 1 unit increase in MA. In the groups who had diabetes mellitus and hypertension, there was no correlation between MA and Gensini score. The results of the present study suggest that MA is associated with the severity of CAD independent of other cardiovascular risk factors. 相似文献
66.
67.
Mathieu Bangert Adam K. Wright Jamie Rylance Matthew J. Kelly Angela D. Wright George M. Carlone Jacquelyn S. Sampson Gowrisankar Rajam Edwin W. Ades Aras Kadioglu Stephen B. Gordon 《Antimicrobial agents and chemotherapy》2013,57(9):4566-4569
New treatment strategies are urgently needed to overcome early mortality in acute bacterial infections. Previous studies have shown that administration of a novel immunoactivating peptide (P4) alongside passive immunotherapy prevents the onset of septicemia and rescues mice from lethal invasive disease models of pneumococcal pneumonia and sepsis. In this study, using two diverse populations of adult volunteers, we determined whether P4 treatment of human alveolar macrophages would upregulate phagocytic killing of Streptococcus pneumoniae
ex vivo. We also measured macrophage intracellular oxidation, cytokine secretion, and surface marker expression following stimulation. Peptide treatment showed enhanced bacterial killing in the absence of nonspecific inflammation, consistent with therapeutic potential. This is the first demonstration of P4 efficacy on ex vivo-derived human lung cells. 相似文献
68.
Hakan Akinci Aysegul Kapucu Kadriye Akgun Dar Ozlem Celik Banu Tutunculer Gozde Sirin Buge Oz Nurperi Gazioglu Haluk Ince Süheyla Aliustaoglu Pinar Kadioglu 《Pituitary》2013,16(3):386-392
The aim of the study was to evaluate the presence of aromatase cytochrome P450 enzyme (P450AROM) expression in normal pituitary tissues and tumor tissues of patients with prolactinoma and to examine the impact of the P450AROM expression on clinical outcome. Twenty-six consecutive human pituitary tissue samples were obtained from autopsies performed at the Institute of Forensic Medicine. Sixty-four patients who had an adenomectomy between 2000 and 2009 after prolactinoma diagnosis with histologically confirmed pituitary tumor tissues were retrospectively included in this study. The slices from the pituitary tissues were subjected to immunohistochemical staining for evaluation of P450AROM and estrogen receptor beta (ER beta) subunit. Immunohistochemistry results were compared according to age, gender, remission rate, resistance and invasion status of the patients. Higher than normal P450AROM expression was found in the pituitary tissues of the patients with prolactinoma (p < 0.001). P450AROM intensity had no relation to resistance or remission in patients with prolactinoma (p = 0.44, p = 0.45, respectively). The subgroup analysis showed that compared to males without invasive adenoma, males with invasive adenoma had higher P450AROM expression (p = 0.048). ER beta was found to have an impact on resistance (p = 0.049). This study shows that P450AROM expression is present in the pituitary tissues of patients with prolactinoma and that this presence could be important in development and tumor behavior of prolactinomas. 相似文献
69.
70.
Objective: To investigate the effects of topical travoprost 0.004% and topical bimatoprost 0.03% on retrobulbar blood flow (RBF). Methods: Nineteen young healthy men without any known ocular or systemic disorder were enrolled in this prospective, double-masked, randomized, cross-over study. Baseline RBF mea- 相似文献