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91.
Omar A. Hussein Khairul Habib R. Saidur Ali S. Muhsan Syed Shahabuddin Omer A. Alawi 《RSC advances》2019,9(66):38576
Covalent functionalization (CF-GNPs) and non-covalent functionalization (NCF-GNPs) approaches were applied to prepare graphene nanoplatelets (GNPs). The impact of using four surfactants (SDS, CTAB, Tween-80, and Triton X-100) was studied with four test times (15, 30, 60, and 90 min) and four weight concentrations. The stable thermal conductivity and viscosity were measured as a function of temperature. Fourier transform infrared spectroscopy (FTIR), thermo-gravimetric analysis (TGA), X-ray diffraction (XRD) and Raman spectroscopy verified the fundamental efficient and stable CF. Several techniques, such as dispersion of particle size, FESEM, FETEM, EDX, zeta potential, and UV-vis spectrophotometry, were employed to characterize both the dispersion stability and morphology of functionalized materials. At ultrasonic test time, the highest stability of nanofluids was achieved at 60 min. As a result, the thermal conductivity displayed by CF-GNPs was higher than NCF-GNPs and distilled water. In conclusion, the improvement in thermal conductivity and stability displayed by CF-GNPs was higher than those of NCF-GNPs, while the lowest viscosity was 8% higher than distilled water, and the best thermal conductivity improvement was recorded at 29.2%.Covalent functionalization (CF-GNPs) and non-covalent functionalization (NCF-GNPs) approaches were applied to prepare graphene nanoplatelets (GNPs). 相似文献
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Cystatin C is better than albuminuria as a predictor of pulse wave velocity in hypertensive patients
Abdullah Ozkok Timur Selcuk Akpinar Fatih Tufan Omer Kaya Hamza Ugur Bozbey Riza Atas 《Clinical and experimental hypertension (New York, N.Y. : 1993)》2014,36(4):222-226
Introduction: Arterial stiffness is important in the evaluation of the cardiovascular risk in both general population and hypertensive patients. In this study, we aimed to investigate the associations of both serum cystatin C levels and albuminuria with arterial stiffness in healthy controls and hypertensive patients.Patients and methods: Seventy-six healthy controls (male/female?=?44/32) and 76 hypertensive patients (male/female?=?43/33) were enrolled. Arterial stiffness parameters such as augmentation index (AIx) and pulse wave velocity (PWV) were non-invasively measured with the Arteriograph (Tensiomed Ltd., Budapest, Hungary).Results: AIx (31.92?±?14.31 vs. 27.95?±?11.03, p?=?0.03) and PWV (9.84?±?1.62 vs. 8.87?±?2.04, p?0.001) were significantly higher in hypertensive patients compared to healthy controls. Patients with microalbuminuria had significantly higher AIx (43.47?±?9.91 vs. 30.37?±?14.13, p?=?0.002) and higher serum cystatin C levels [0.76 (0.67–0.95) vs. 0.68 (0.62–0.78) mg/L, p?=?0.03]. In the hypertensive group, AIx was significantly correlated with PWV (r?=?0.519, p?0.001), glomerular filtration rate (cystatin C) (r?=?–0.438, p?=?0.003), mean arterial pressure (MAP) (r?=?0.288, p?=?0.015) and urinary albumin–creatinine ratio (ACR) (r?=?0.386, p?=?0.004). PWV was associated with serum cystatin C (r?=?0.442, p?=?0.003) and MAP (r?=?0.377, p?=?0.001). In the linear regression analysis (model r?=?0.577, p?=?0.006) for the prediction of PWV in hypertensive patients, MAP, urinary ACR, age and serum cystatin C levels were included as independent variables. Cystatin C was found to be the significant determinant of PWV in hypertensive patients.Conclusion: Multivariate analysis revealed that serum cystatin C but not albuminuria was significantly associated with PWV in hypertensive patients. Serum cystatin C may be better than albuminuria as a predictor of arterial stiffness in hypertensive patients. 相似文献
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Mehmet Sevki Uyanik Gulsum Emel Pamuk Omer Nuri Pamuk Sedat Alpaslan Tuncel 《Thrombosis research》2014
Background
Gouty arthritis (GA) is a chronic inflammatory arthritis in which both clinical and subclinical atherosclerosis are more frequent. The dynamic equilibrium between coagulation and fibrinolysis is impaired in inflammatory diseases. We determined TFPI and TAFI antigen levels in GA patients and evaluated their association with subclinical atherosclerosis.Methods
We included 45 GA patients (41 males, 4 females; mean age: 51.6 years) and 25 asymptomatic hyperuricemic (AHU) subjects (19 males, 6 females; mean age: 48.1 years). Cardiovascular risk factors were determined. TAFI and TFPI levels were determined by ELISA. B-mode ultrasonography was used to detect subclinical atherosclerosis.Results
Cardiovascular risk factors were similar in both groups. The carotid IMT was significantly higher in GA group than in AHU group (0.74 ± 0.23 mm vs. 0.61 ± 0.13 mm, p = 0.009). TFPI level was significantly higher in GA group than in AHU group (86.2 ± 48.9 ng/mL vs. 25.8 ± 21.4 ng/mL, p < 0.001); TAFI antigen was significantly higher in AHU group (22.6 ± 3.6 ng/mL vs. 25.7 ± 5.3 ng/mL, p = 0.006) than in GA patients. Atherosclerotic plaque formation was more frequent in GA group (p = 0.041). When GA patients with and without plaques were compared, the first group had significantly higher mean age (p = 0.01) and TFPI level (p = 0.028). TFPI level correlated with carotid IMT (r = 0.302; p = 0.028). Logistic regression analysis showed that age (OR: 1.236, 95%CI: 1.059-1.443, p = 0.007) and TFPI (OR: 1.031, 95%CI: 1.008-1.054, p = 0.008) were independent risk factors for the presence of plaques.Conclusions
GA patients had more frequent subclinical atherosclerosis than subjects with AHU. Higher TFPI levels in GA patients –probably associated with enhanced endothelial damage- were related to subclinical atherosclerosis. Lower TAFI levels in GA pointed to impaired fibrinolysis. 相似文献96.
97.
Isilak Z Kardesoglu E Aparci M Uz O Yalcin M Yiginer O Cingozbay BY Uzun M 《Kardiologia polska》2012,70(3):242-250
98.
RC Iskow O Gokcumen A Abyzov J Malukiewicz Q Zhu AT Sukumar AA Pai RE Mills L Habegger DA Cusanovich MA Rubel GH Perry M Gerstein AC Stone Y Gilad C Lee 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(31):12656-12661
Gene expression differences are shaped by selective pressures and contribute to phenotypic differences between species. We identified 964 copy number differences (CNDs) of conserved sequences across three primate species and examined their potential effects on gene expression profiles. Samples with copy number different genes had significantly different expression than samples with neutral copy number. Genes encoding regulatory molecules differed in copy number and were associated with significant expression differences. Additionally, we identified 127 CNDs that were processed pseudogenes and some of which were expressed. Furthermore, there were copy number-different regulatory regions such as ultraconserved elements and long intergenic noncoding RNAs with the potential to affect expression. We postulate that CNDs of these conserved sequences fine-tune developmental pathways by altering the levels of RNA. 相似文献
99.
Ulus Y Durmus D Akyol Y Terzi Y Bilgici A Kuru O 《Archives of gerontology and geriatrics》2012,54(3):429-433
The FES-I is a questionnaire which was developed to assess fear of falling. The aim of this study was to evaluate validity and reliability of a Turkish language version of the FES-I in Turkish older people. The study sample included 70 volunteers with an age range of 65-81. To assess the test-retest reliability of the Turkish FES-I, questionnaire was applied again 10-15 days after the first interview (interclass correlation: ICC). FES-I was compared with The Modified Barthel Index (MBI), the timed up and go test (TUG), and The Berg Balance Scale (BBS) for construct validity. Cronbach's alpha (α) was used to evaluate the internal consistency. The internal structure of the FES-I was examined by factor analysis. ROC plots were used to define cut-point for the FES-I scales. Cronbach's α of the Turkish FES-I was 0.94 and the individual item ICC ranged from 0.97 to 0.99. The Turkish FES-I total scores were correlated with TUG positively, and MBI, and BBS negatively. The cut-off score to differentiate between persons with fear of falling and persons without fear of falling was 24 points. It was found that the Turkish version of the FES-I was a reliable and valid measure of fear of falling in Turkish older people. 相似文献
100.
Kaya MG Uyarel H Akpek M Kalay N Ergelen M Ayhan E Isik T Cicek G Elcik D Sahin O Cosgun SM Oguzhan A Eren M Gibson CM 《The American journal of cardiology》2012,109(4):486-491
Elevated uric acid (UA) levels have been associated with cardiovascular disease in epidemiologic studies. The relation between UA levels and long-term outcomes in patients with ST-segment elevation myocardial infarction who undergo primary percutaneous coronary intervention is not known. Data from 2,249 consecutive patients with ST-segment elevation myocardial infarction who underwent primary percutaneous coronary intervention were evaluated. Patients were divided into 2 groups with high or low UA using upper limits of normal of 6 mg/dl for women and 7 mg/dl for men. There were 1,643 patients in the low-UA group (mean age 55.9 ± 11.6 years, 85% men) and 606 patients in the high-UA group (mean age 60.5 ± 12.6 years, 76% men). Serum UA levels were 8.0 ± 1.5 mg/dl in the high-UA group and 5.2 ± 1.0 mg/dl in the low-UA group (p <0.001). The in-hospital mortality rate was significantly higher in patients with high UA levels (9% vs 2%, p <0.001), as was the rate of adverse outcomes in patients with high UA. The mean follow-up time was 24.3 months. Cardiovascular mortality, reinfarction, target vessel revascularization, heart failure, and major adverse cardiac events were all significantly higher in the high-UA group. In a multivariate analyses, high plasma UA levels were an independent predictor of major adverse cardiac events in the hospital (odds ratio 2.03, 95% confidence interval 1.25 to 3.75, p = 0.006) and during long-term follow-up (odds ratio 1.64, 95% confidence interval 1.05 to 2.56, p = 0.03). In conclusion, high UA levels on admission are independently associated with in-hospital and long-term adverse outcomes in patients with ST-segment elevation myocardial infarction who undergo primary percutaneous coronary intervention. 相似文献