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61.
Ozkara A Cetin G Mert M Akinci O Erdem CC Suzer K 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2005,32(2):151-153
We report a case of successful reoperation for aortic arch dissection with use of the "arch-first" technique in a patient who had Marfan syndrome. Extracorporeal circulation was initiated via right subclavian artery cannulation, and the chest was entered through a clamshell incision for the best exposure. When the patient was cooled to 18 degrees C, the perfusion was stopped. After the 1st aortic arch anastomosis to a 30-mm Dacron graft, cerebral perfusion was reestablished via the right subclavian artery. The aortic repair was then completed. The cerebral ischemic time was 18 minutes, the aortic cross-clamp time was 69 minutes, and the total extracorporeal circulation time was 334 minutes. The patient was discharged from the hospital on postoperative day 10 with no neurologic impairment. The arch-first technique shortens the duration of brain ischemia. When combined with a clamshell incision, the technique is particularly helpful for reoperation of the aortic arch and thoracic aorta. 相似文献
62.
Mehmet?DoganEmail authorView authors OrcID profile Tolga?Han?Efe Tolga?Cimen Cem?Ozisler Mehmet?Ali?Felekoglu Ahmet?Goktug?Ertem Mehmet?Erat Omer?Yiginer Murat?Tulmac 《Lung》2018,196(2):173-178
Objectives
Systemic sclerosis (SSc) is a chronic, inflammatory, and autoimmune connective tissue disease that is associated with vascular lesions, and fibrosis of the skin and visceral organs. Cardiac complications may occur as a secondary effect of SSc as a result of pulmonary arterial hypertension and interstitial lung disease. The objective of this study was to assess whether the pulmonary pulse transit time (pPTT) could serve as a diagnostic marker for pulmonary arterial alterations in patients with SSc, prior to development of pulmonary hypertension.Methods
Twenty-five SSc patients as a study group and 25 age- and sex-matched healthy volunteers for the control group were recruited to the study. Right ventricle function parameters, such as tricuspid annular plane systolic excursion (TAPSE), estimated pulmonary artery systolic pressure (ePASP), right ventricular dimensions, right ventricle fractional area changes, and myocardial perfusion index (MPI) were measured and calculated. Pulmonary pulse transit time was defined as the time interval between the R-wave peak in the ECG and the corresponding peak late systolic pulmonary vein flow velocity.Results
Right ventricle myocardial performance index (RVMPI) and eSPAP were significantly higher in the SSc group than the controls (p?=?0.032, p?=?0.012, respectively). Pulmonary pulse transit time and TAPSE was shorter in the patients with SSc (p?=?0.006, p?=?0.015, respectively). In correlation analysis, pPTT was inversely correlated with RVMPI (r?=???0.435, p?=?0.003), eSPAP (r?=???0.434, p?=?0.003), and disease duration (r?=???0.595, p?=?0.003). Conversely, it positively correlated with TAPSE (r?=?0.345, p?=?0.022).Conclusion
pPTT was found to be shorter in SSc patients. pPTT might serve as a surrogate marker of pulmonary hemodynamics in patients with SSc, even prior to the development of pulmonary hypertension.63.
Consistent copy number changes and recurrent PRKAR1A mutations distinguish Melanotic Schwannomas from Melanomas: SNP‐array and next generation sequencing analysis 下载免费PDF全文
Lu Wang Ahmet Zehir Justyna Sadowska Nengyi Zhou Marc Rosenblum Klaus Busam Narasimhan Agaram William Travis Maria Arcila Snjezana Dogan Michael F. Berger Donavan T. Cheng Marc Ladanyi Khedoudja Nafa Meera Hameed 《Genes, chromosomes & cancer》2015,54(8):463-471
Melanotic Schwannomas (MS) are rare tumors that share histological features with melanocytic tumors and schwannomas. However, their genetics are poorly understood. To elucidate the genetic characteristics of MS, we performed genome‐wide studies in a series of cases. Twelve MS cases were available for the study. Genomic DNAs extracted from formalin‐fixed paraffin embedded tumor tissues were subjected to copy number (CN) and allelic imbalance (AI) analysis by Single Nucleotide Polymorphism (SNP)‐array and screened for mutations in coding exons of 341 key cancer‐associated genes using a hybrid capture‐based next‐generation sequencing (NGS) assay. Sanger sequencing was used to further verify recurrent mutations detected by NGS study. SNP‐array analysis revealed remarkably stereotypic chromosomal abnormalities in MS. Hypodiploidy was common, typically involving monosomies of chromosomes 1, 2, and 17. All 12 samples showed mutations in PRKAR1A gene, including 2 cases with 2 mutations each. The 14 mutations were scattered across PRKAR1A, and most were inactivating mutations. AI on 17q, presenting as loss of heterozygosity with or without CN losses, combined with a PRKAR1A mutation was observed in 9/12 MS cases. The remaining 3 cases included the two samples harboring two mutations in PRKAR1A. MS exhibits a stereotypic pattern of chromosomal losses. In contrast, melanomas are typically characterized by the presence of multiple CN aberrations, without demonstrable differences in the frequency of losses and gains. Inactivation of both alleles of PRKAR1A by “two hits” observed in almost all cases underscores the central role of PRKAR1A in the pathogenesis of this neoplasm. © 2015 Wiley Periodicals, Inc. 相似文献
64.
Mert İlker Hayıroğlu Muhammed Keskin Ahmet Okan Uzun Emrah Bozbeyoğlu Özlem Yıldırımtürk Ömer Kozan Seçkin Pehlivanoğlu 《The international journal of cardiovascular imaging》2018,34(3):329-336
SYNTAX Score II (SSII) connects clinical variables with coronary anatomy. We investigated the prognostic value of SSII in patients with ST segment elevated myocardial infarction (STEMI) complicated with cardiogenic shock treated with primary percutaneous coronary intervention (PPCI). In this retrospective analysis, we evaluated the in-hospital prognostic impact of SSII on 492 patients with STEMI complicated with cardiogenic shock treated with PPCI. Patients were stratified by tertiles of SSII, in-hospital clinical outcomes were compared between those groups. In-hospital univariate analysis revealed higher rates of in-hospital death for patients with SSII in tertile 3, as compared to patients with SSII in tertile 1 (OR 17.4, 95% CI 10.0–30.2, p?<?0.001). After adjustment for confounding baseline variables, SSII in tertile 3 was associated with 6.2-fold hazard of in-hospital death (OR 6.2, 95% CI 2.6–14.1, p?<?0.001). SSII in patients with STEMI complicated with cardiogenic shock treated with PPCI provide an independent prognostic marker of in-hospital outcomes. Our data suggests SSII to be a simple, feasible and clinically applicable tool for rapid risk stratification in patients with STEMI complicated with cardiogenic shock treated with PPCI. 相似文献
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67.
Cagla Celik Didar Tasdemir Ayse Demirbas Ahmet Kat O. Tolga Gul Behzat Cimen Ismail Ocsoy 《RSC advances》2018,8(45):25298
The discovery of functional organic–inorganic hybrid nanoflowers (FNFs) consisting of proteins/enzymes as the organic components and Cu(ii) ion as the inorganic component has made an enormous impact on enzyme immobilization studies. The FNFs synthesized by an encouraging and novel approach not only showed high stabilities but also much enhanced catalytic activities as compared to free and conventionally immobilized enzymes. A recent development demonstrated that FNF formation has moved beyond the initial discovery in which enzymes and Cu2+ ions used as the organic and inorganic parts, respectively, are replaced with new organic (chitosan, amino acid and plant extracts) and inorganic (Cu2+ and Fe2+) materials. The new organic materials incorporated into FNFs act as Fenton-like agents and then show peroxidase-like activity owing to the metal ions and the porous structure of FNFs in the presence of hydrogen peroxide (H2O2). All FNFs have been widely utilized in many different scientific and industrial fields due to their greatly enhanced activities and stabilities. This review focuses primarily on the preparation, characterization, and bioanalytical applications of FNFs and explains the mechanisms of their formation and enhanced activities and stabilities.The discovery of functional organic–inorganic hybrid nanoflowers (FNFs) consisting of proteins/enzymes as the organic components and Cu(ii) ion as the inorganic component has made an enormous impact on enzyme immobilization studies. 相似文献
68.
Suna Sabuncuoglu Ayse Eken Ahmet Aydin Hilal Ozgunes Hilmi Orhan 《Drug and chemical toxicology》2015,38(4):375-382
We explored the association between the activities of antioxidant enzymes and their metallic cofactors in rats treated with cisplatin. The antioxidant effects of aminoguanidine, and a combination of vitamins E and C were investigated. Plasma platin was significantly lower than liver and kidney. Cisplatin treatment caused significant increase in plasma Se-glutathione peroxidase activity. Activities of Se-glutathione peroxidase, glutathione S-transferase, catalase and Cu,Zn-superoxide dismutase have been found to be significantly decreased in liver and kidney compared to controls. Zn levels in these organs were diminished upon cisplatin treatment, while levels of Cu were unaffected. Interestingly, levels of iron, the cofactor of catalase, were found to be significantly increased in liver and kidney. Intervention with aminoguanidine or vitamins was generally prevented cisplatin-caused changes in the activity of enzymes and in the tissue levels of cofactor metals. These observations suggest that relation between activities of enzymes and levels of cofactor metals is multifactorial. 相似文献
69.
Nedim Durmus Sefa Gültürk Tijen Kaya Tuncer Demir Mesut Parlak Ahmet Altun 《Indian journal of pharmacology》2015,47(1):34-38
Objectives:It is suggested that excessive calcium entry into neurons is the main triggering event in the initiation of epileptic discharges. We aimed to investigate the role of T and N type calcium channels in absence epilepsy experimental model.Results:Beta and delta recording ratios in 1 μM/5 μl mibefradil group was significantly different from basal and other dose-injected groups. Beta, alpha, and theta recordings in 0.2 μM/5 μl w-Conotoxin MVIIA group was significantly different from basal and other dose-injected groups. In w-Conotoxin MVIIA after mibefradil group, beta, alpha, and theta recording ratios were significantly different from basal and mibefradil group. Mibefradil and w-Conotoxin MVIIA significantly decreased the frequency and duration of SWDs. The decrease of frequency and duration of SWDs in mibefradil group was significantly different from w-Conotoxin MVIIA group. The frequency and duration of SWDs significantly decreased in w-Conotoxin MVIIA after mibefradil group compared with basal, mibefradil, and w-Conotoxin MVIIA groups.Conclusions:We concluded that both T and L type calcium channels play activator roles in SWDs and have positive effects on frequency and duration of these discharges. These results are related with their central effects more than peripheral effects.KEY WORDS: Epilepsy, mibefradil, T and N type calcium channels, Wistar Albino Glaxo/Rij rats, w-Conotoxin MVIIA 相似文献
70.
Sahin Serdar Gundogdu Aycan Nalbantoglu Ufuk Kadioglu Pinar Karaca Zuleyha Hacioglu Aysa Urhan Muhammed Emre Unluhizarci Kursad Demir Ahmet Numan Hora Mehmet Durcan Emre Elbüken Gülsah Dokmetas Hatice Sebile Zuhur Sayid Shafi Kelestimur Fahrettin 《Pituitary》2022,25(3):520-530
Pituitary - Our aim was to investigate the changes in the composition of oral and gut microbiota in patients with newly diagnosed acromegaly and their relationship with IGF-1 levels. Oral and fecal... 相似文献