3,549 research outputs found

    Effects of fluid resuscitation on cerebral tissue oxygenation changes in a piglet model of hemorrhagic shock

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    AbstractBackgroundAcute blood loss linked to severe hypovolemia and hemorrhagic shock is a critical condition in pediatric intensive care. This study was to investigate the role of various fluid resuscitation approaches to cerebral tissue oxygenation using a piglet model of hemorrhagic shock.MethodsThirty piglets received blood removal to induce hemorrhagic shock, and then were randomly assigned to a control group (no treatment), a control-normal saline (NS) group (treated with bolus normal saline 10mL/kg only), or one of three treatment groups treated with 15mL/kg/dose fluid every 30min with either whole blood (WB), lactated Ringer’s solution (LR), or NS in addition to an initial bolus of saline. The piglets’ physiological profiles, arterial blood gases, and regional cerebral oxygen saturation (rScO2) levels were recorded, fractional tissue oxygen extraction was calculated, and blood hemoglobin levels were measured.ResultsThe results showed that no matter whether treated with only one dose of bolus NS (control-NS group) or with extra WB, LR, or NS, all the treated animals had a significantly higher survival rate, mean arterial blood pressure (MAP), arterial oxygen tension, arterial oxygen saturation, and rScO2 than the control group (p<0.05). Animals treated with WB all survived the full experimental period, and their hemoglobin levels, MAP, and rScO2 were the highest comparing to all other groups (p<0.05).ConclusionEffective resuscitation using a high concentration of inspired oxygen and adequate fluid infusion, either as a single-dose bolus of NS or combining this with a subsequent transfusion of WB, LR, or NS, helped to stabilize the cardiovascular condition of the tested young subjects and improved cerebral tissue oxygenation over the emergent first four hours. Furthermore, WB was the best fluid choice when used in addition to the bolus NS challenge for maintaining better brain tissue oxygenation when treating hemorrhagic shock

    Effect of Nonlinear Multi-axial Elasticity and Anisotropic Plasticity on Quasi-static Dent Properties of Automotive Steel Sheets

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    This study investigates the influence of the elasto-plastic properties of automotive steel sheets on the denting behavior and suggests a constitutive modeling approach for reliable dent analysis. The stress strain behaviors of three kinds of steel sheets were measured in uniaxial tension, in-plane biaxial tension and forward-reverse simple shear tests. Advanced constitutive models were employed to capture the plastic anisotropy, reverse loading characteristics such as the Bauschinger effect, and elastic modulus degradation. In particular, the biaxial elastic modulus and its degradation behavior were measured and implemented in the constitutive model. The suggested model significantly improved the prediction of dents compared to the conventional model in terms of the load-displacement curve. Sensitivity studies on the constitutive model demonstrated that mainly plastic anisotropy and elastic behavior of a material influence the panel stiffness, whereas the reverse loading behavior strongly affects the permanent dent depth. (C) 2016 Elsevier Ltd. All rights reserved.1151Ysciescopu

    Molecular lens of the nonresonant dipole force

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    A cylindrical molecular lens is formed by focusing a nanosecond IR laser pulse. Trajectories of a CS2 molecular beam deflected by the lens are traced using the velocity map imaging technique. The characteristic lens parameters including the focal length, minimum beam width, and distance to the minimum-width position are determined. The laser intensity dependence of the parameters is in good agreement with theoretical predictions. Exciting possibilities for molecular optics and a new type of optical chromatography are opened up.open394

    Chemical ordering in PtNi nanocrystals

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    We investigated the chemical ordering in PtNi nanocrystals fabricated on sapphire substrate using in-situ synchrotron X-ray scattering. Nanocrystals with composition close to 1:1 were ordered in the tetragonal L1(0) structure at low temperatures. The transition to disordered FCC structure occurred at around 640 degrees C and substantial hysteresis of about 50 K was observed. Nanocrystals of smaller sizes fabricated under the same conditions were Ni rich and ordered into Cu3Au type L1(2) structure. Significantly higher degree of chemical ordering was observed in L1(2) structure than in L1(0) structure. (C) 2016 Elsevier B.V. All rights reserved.1144Ysciescopu

    Analyzing Coronary Artery Disease in Patients with Low CAC Scores by 64-Slice MDCT

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    Purpose. Coronary artery calcification (CAC) scores are widely used to determine risk for Coronary Artery Disease (CAD). A CAC score does not have the diagnostic accuracy needed for CAD. This work uses a novel efficient approach to predict CAD in patients with low CAC scores. Materials and Methods. The study group comprised 86 subjects who underwent a screening health examination, including laboratory testing, CAC scanning, and cardiac angiography by 64-slice multidetector computed tomographic angiography. Eleven physiological variables and three personal parameters were investigated in proposed model. Logistic regression was applied to assess the sensitivity, specificity, and accuracy of when using individual variables and CAC score. Meta-analysis combined physiological and personal parameters by logistic regression. Results. The diagnostic sensitivity of the CAC score was 14.3% when the CAC score was ≤30. Sensitivity increased to 57.13% using the proposed model. The statistically significant variables, based on beta values and P values, were family history, LDL-c, blood pressure, HDL-c, age, triglyceride, and cholesterol. Conclusions. The CAC score has low negative predictive value for CAD. This work applied a novel prediction method that uses patient information, including physiological and society parameters. The proposed method increases the accuracy of CAC score for predicting CAD

    Application of a virtual reality prototype for pain relief of pediatric burn in Taiwan

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    Author name used in this publication: Joanne W. Y. Chung2006-2007 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

    Suppression of low-density lipoprotein oxidation, vascular smooth muscle cell proliferation and migration by a herbal extract of Radix Astragali, Radix Codonopsis and Cortex Lycii

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    <p>Abstract</p> <p>Background</p> <p>Atherosclerosis is a major cause of death in developed world. Atherosclerosis is characterized by low-density lipoprotein deposition in the arterial wall which ultimately begets the formation of lesions. Rupture of lesions finally leads to clinical events such as heart attack and stroke. Atherosclerosis is a complication associated with diabetes. In patients with diabetes, the risk of atherosclerosis is three to five folds greater than in non-diabetics. Our previous study showed that a herbal extract of <it>Radix Astragali, Radix Codonopsis </it>and <it>Cortex Lycii</it>, namely SR10, could improve glucose homeostasis both <it>in vitro </it>and <it>in vivo</it>. In this study, we want to further investigate the efficacy of SR10 in treating atherosclerosis.</p> <p>Method</p> <p>The inhibitory effect of SR10 on low-density lipoprotein oxidation was investigated using free radical-induced erythrocyte hemolysis model and copper ion-induced low-density lipoprotein oxidation model. Since vascular smooth muscle cell proliferation and migration are important processes in atherogenesis, we also examined the effect of SR10 in inhibiting these events.</p> <p>Results</p> <p>Our results showed that SR10 inhibited erythrocyte hemolysis with IC<sub>50 </sub>value at 0.25 mg/ml and significantly prolonged low-density lipoprotein oxidation <it>in vitro</it>. SR10 attenuated platelet derived growth factor-BB-induced vascular smooth muscle cell proliferation by promoting cell cycle arrest at G<sub>0</sub>/G<sub>1 </sub>phase as well as inhibiting vascular smooth muscle cell migration.</p> <p>Conclusion</p> <p>The potential application of SR10 in treating atherosclerosis has been implied in this study. Animal model will be needed to further verify the efficacy of SR10 in future.</p

    Is lymphovascular invasion a powerful predictor for biochemical recurrence in pT3 N0 prostate cancer?: Results from the K-CaP database

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    To assess the impact of lymphovascular invasion (LVI) on the risk of biochemical recurrence (BCR) in pT3 N0 prostate cancer, clinical data were extracted from 1,622 patients with pT3 N0 prostate cancer from the K-CaP database. Patients with neoadjuvant androgen deprivation therapy (n = 325) or insufficient pathologic or follow-up data (n = 87) were excluded. The primary endpoint was the oncologic importance of LVI, and the secondary endpoint was the hierarchical relationships for estimating BCR between the evaluated variables. LVI was noted in 260 patients (21.5%) and was significantly associated with other adverse clinicopathologic features. In the multivariate Cox regression analysis, LVI was significantly associated with an increased risk of BCR after adjusting for known prognostic factors. In the Bayesian belief network analysis, LVI and pathologic Gleason score were found to be first-degree associates of BCR, whereas prostate-specific antigen (PSA) level, seminal vesicle invasion, perineural invasion, and high-grade prostatic intraepithelial neoplasia were considered second-degree associates. In the random survival forest, pathologic Gleason score, LVI, and PSA level were three most important variables in determining BCR of patients with pT3 N0 prostate cancer. In conclusion, LVI is one of the most powerful adverse prognostic factors for BCR in patients with pT3 N0 prostate cancer.1132Ysciescopu

    Severity of Nonalcoholic Fatty Liver Disease is Associated with Development of Metabolic Syndrome: Results of a 5-Year Cohort Study

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    Aims: Nonalcoholic fatty liver disease (NAFLD) is considered to be a hepatic manifestation of metabolic syndrome (MS). However, a few studies have examined the effect of NAFLD on the development of MS. We evaluated the relationship between the development of MS and clinical severity of NAFLD according to alanine aminotransferase (ALT) levels. Methods: A retrospective cohort study was conducted. Participants who underwent abdominal ultrasonography and blood samplings for health check-ups both in 2005 and 2010 were recruited. NAFLD was diagnosed if a person showed fatty liver on ultrasonography without significant alcohol consumption. Subjects with MS at baseline were excluded. Results: A total of 2,728 subjects met the inclusion criteria. Fatty liver (FL) with normal ALT was found in 369 (13.5%) subjects and FL with elevated ALT in 328 (12.0%). During 5 years of follow up, 582 (21.3%) incident cases of MS developed between 2005 and 2010. The incidence of MS was higher in patients with NAFLD compared to control group (41.2% in FL with elevated ALT, 34.7% in FL with normal ALT and 15.7% in control, p<0.001). Multivariate analysis showed that odds ratio (OR) and 95% confidence interval (CI) for MS increased according to the severity of NAFLD [OR (95% CI), 1.29 (0.97−1.71) in FL with normal ALT and 1.54 (1.18−1.33) in FL with elevated ALT, p=0.01]. Conclusions: We have demonstrated that development of MS is significantly increased according to the clinical severity of NAFLD. These findings have implications in the clinical availability of NAFLD as a predictor of MS
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