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101.
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
102.
103.
Gallup AC Hale JJ Sumpter DJ Garnier S Kacelnik A Krebs JR Couzin ID 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(19):7245-7250
Pedestrian crowds can form the substrate of important socially contagious behaviors, including propagation of visual attention, violence, opinions, and emotional state. However, relating individual to collective behavior is often difficult, and quantitative studies have largely used laboratory experimentation. We present two studies in which we tracked the motion and head direction of 3,325 pedestrians in natural crowds to quantify the extent, influence, and context dependence of socially transmitted visual attention. In our first study, we instructed stimulus groups of confederates within a crowd to gaze up to a single point atop of a building. Analysis of passersby shows that visual attention spreads unevenly in space and that the probability of pedestrians adopting this behavior increases as a function of stimulus group size before saturating for larger groups. We develop a model that predicts that this gaze response will lead to the transfer of visual attention between crowd members, but it is not sufficiently strong to produce a tipping point or critical mass of gaze-following that has previously been predicted for crowd dynamics. A second experiment, in which passersby were presented with two stimulus confederates performing suspicious/irregular activity, supports the predictions of our model. This experiment reveals that visual interactions between pedestrians occur primarily within a 2-m range and that gaze-copying, although relatively weak, can facilitate response to relevant stimuli. Although the above aspects of gaze-following response are reproduced robustly between experimental setups, the overall tendency to respond to a stimulus is dependent on spatial features, social context, and sex of the passerby. 相似文献
104.
Akman T Akarsu M Akpinar H Resmi H Taylan E Sezer E 《Digestive diseases and sciences》2012,57(2):458-464
Background
Oxidative stress and reduced microvascular flow are important factors in the pathogenesis of inflammatory bowel disease (IBD). The increased oxidative stress reduces the eriytrocyte deformability. However, in IBD, there are no studies in the literature which evaluate erythrocyte deformability. 相似文献105.
Schwartz BG Kloner RA Thomas JL Bui Q Mayeda GS Burstein S Hale SL Economides C French WJ 《The American journal of cardiology》2012,110(3):461-466
This report focuses on cardioprotection and describes the advantages and disadvantages of various methods of inducing therapeutic hypothermia (TH) with regard to neuroprotection and cardioprotection for patients with cardiac arrest and ST-segment elevation myocardial infarction (STEMI). TH is recommended in cardiac arrest guidelines. For patients resuscitated after out-of-hospital cardiac arrest, improvements in survival and neurologic outcomes were observed with relatively slow induction of TH. More rapid induction of TH in patients with cardiac arrest might have a mild to modest incremental impact on neurologic outcomes. TH drastically reduces infarct size in animal models, but achievement of target temperature before reperfusion is essential. Rapid initiation of TH in patients with STEMI is challenging but attainable, and marked infarct size reductions are possible. To induce TH, a variety of devices have recently been developed that require additional study. Of particular interest is transcoronary induction of TH using a catheter or wire lumen, which enables hypothermic reperfusion in the absence of total-body hypothermia. At present, the main methods of inducing and maintaining TH are surface cooling, endovascular heat-exchange catheters, and intravenous infusion of cold fluids. Surface cooling or endovascular catheters may be sufficient for induction of TH in patients resuscitated after out-of-hospital cardiac arrest. For patients with STEMI, intravenous infusion of cold fluids achieves target temperature very rapidly but might worsen left ventricular function. More widespread use of TH would improve survival and quality of life for patients with out-of-hospital cardiac arrest; larger studies with more rapid induction of TH are needed in the STEMI population. 相似文献
106.
107.
Urethral adenocarcinoma associated with intestinal-type metaplasia,case report and literature review
Christopher S Hale Hongying Huang Jonathan Melamed Ruliang Xu Larry Roberts Rosemary Wieczorek Zhiheng Pei Peng Lee 《International journal of clinical and experimental pathology》2013,6(8):1665-1670
The presence of glandular epithelium in urinary tract biopsies poses a diagnostic challenge. Intestinal metaplasia of the urethra may be seen in many congenital, iatrogenic, and reactive conditions, as well as in association with malignant conditions such as urethral adenocarcinoma. We present a case of a 61 year-old woman presenting with microscopic hematuria. Successive biopsies showed glandular epithelium with focal atypia in close association with inflammation, but no overt malignancy. Only on surgical resection was the associated high grade adenocarcinoma revealed. When intestinal-type mucosa is present within a urinary tract biopsy, associated malignancy may be present only focally. Thorough sampling and consideration of the differential diagnosis is imperative. 相似文献
108.
Erhan Özcan Ali Riza Çetin İsmail Davut Çapar Ali Riza Tunçdemir Hale Ari Aydinbelge 《Odontology / the Society of the Nippon Dental University》2013,101(2):204-209
This study evaluated the influence of eugenol on the push-out bond strengths of fiber posts cemented with different types of resin luting agents. Seventy-two extracted maxillary single-rooted canine teeth were randomly divided into two groups of 36 teeth. Group 1, the control group, was filled with gutta-percha only (i.e., did not receive eugenol), whereas group 2 was filled with a eugenol-containing sealer. All root canals were filled and each group was divided into three subgroups. The posts in each subgroup were cemented with the following materials: subgroup 1 with a 2-step self-etching adhesive system (Clearfil Liner Bond 2V + Panavia F); subgroup 2 with a 1-step self-etching adhesive (Panavia F); and subgroup 3 with a self-adhesive (Clearfil SA Cement). Dislodgement resistance was measured using a universal testing machine. All data were subjected to ANOVA using a factorial design and Tukey test (α = 0.05). The use of the eugenol-containing sealer significantly reduced the push-out bond strength of the fiber post (P < 0.05). The push-out bond strength of Panavia F was significantly higher than those of the other groups filled with the eugenol-containing sealer (P < 0.05). The Panavia F group was less susceptible to the inhibiting effect of eugenol than were the other evaluated groups when the fiber post was cemented in the canals filled with the eugenol-containing sealer. 相似文献
109.
Pediatric traumatic brain injury (TBI) is a major cause of acquired cognitive dysfunction in children. Hippocampal Brain Derived
Neurotrophic Factor (BDNF) is important for normal cognition. Little is known about the effects of TBI on BDNF levels in the
developing hippocampus. We used controlled cortical impact (CCI) in the 17 day old rat pup to test the hypothesis that CCI
would first increase rat hippocampal BDNF mRNA/protein levels relative to SHAM and Na?ve rats by post injury day (PID) 2 and
then decrease BDNF mRNA/protein by PID14. Relative to SHAM, CCI did not change BDNF mRNA/protein levels in the injured hippocampus
in the first 2 days after injury but did decrease BDNF protein at PID14. Surprisingly, BDNF mRNA decreased at PID 1, 3, 7
and 14, and BDNF protein decreased at PID 2, in SHAM and CCI hippocampi relative to Na?ve. In conclusion, TBI decreased BDNF
protein in the injured rat pup hippocampus 14 days after injury. BDNF mRNA levels decreased in both CCI and SHAM hippocampi
relative to Na?ve, suggesting that certain aspects of the experimental paradigm (such as craniotomy, anesthesia, and/or maternal
separation) may decrease the expression of BDNF in the developing hippocampus. While BDNF is important for normal cognition,
no inferences can be made regarding the cognitive impact of any of these factors. Such findings, however, suggest that meticulous
attention to the experimental paradigm, and possible inclusion of a Na?ve group, is warranted in studies of BDNF expression
in the developing brain after TBI. 相似文献
110.
LaRocque RC Rao SR Lee J Ansdell V Yates JA Schwartz BS Knouse M Cahill J Hagmann S Vinetz J Connor BA Goad JA Oladele A Alvarez S Stauffer W Walker P Kozarsky P Franco-Paredes C Dismukes R Rosen J Hynes NA Jacquerioz F McLellan S Hale D Sofarelli T Schoenfeld D Marano N Brunette G Jentes ES Yanni E Sotir MJ Ryan ET;Global TravEpiNet Consortium 《Clinical infectious diseases》2012,54(4):455-462