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91.
Siddhartha Tripathi Amit Prabhakar Nishant Kumar Shiv Govind Singh Amit Agrawal 《Biomedical microdevices》2013,15(3):415-425
In recent years, microfluidic chips have proven ideal tools for biochemical analysis, which, however, demands a unique and compatible plasma separation scheme. Various research groups have established continuous flow separation methods in microfluidic devices; however, they have worked with relatively small dimension microchannels (similar to the blood cell diameter). The present work demonstrates separation of plasma by utilizing the hydrodynamic separation techniques in microchannels with size of the order of mm. The separation process exploits the phenomenon, which is very similar to that of plasma skimming explained under Zweifach-Fung bifurcation law. The present experiments demonstrates for, the first time, that applicability of the Zweifach-Fung bifurcation law can be extended to dimensions much higher than the suspended particle size. The T-microchannel device (comprising perpendicularly connected blood and plasma channels) were micro-fabricated using conventional PDMS micro-molding techniques. Three variables (feed hematocrit, main channel width, and flow rate distributions) were identified as the important parameters which define the device’s efficiency for the blood plasma separation. A plasma separation efficiency of 99.7 % was achieved at a high flow ratio. Novel concepts of 2-stage or multiple plasma channel designs are also proposed to yield high separation efficiency with undiluted blood. The possible underlying principle causing plasma separation (viz. aggregation and shear thinning) are investigated in detail as part of this work. The results are significant because they show nearly 100 % separations in microchannels which are much easier to fabricate than previously designed devices. 相似文献
92.
Nabeel Almotairy Abhishek Kumar Nadia Welander Anastasios Grigoriadis 《European journal of oral sciences》2020,128(4):299-307
To investigate age-related changes in oral motor strategies in response to unpredictable load demands. Sixty-five healthy children (aged 3–17 yr) were divided into five age-groups based on their dental eruption stages and compared with a group of healthy adults (aged 18–35 yr). Each participant was asked to perform a standardized motor control task involving ‘pulling’ and ‘holding’ a force transducer with the anterior teeth. Different loads were attached to the force transducer in an unpredictable manner. The temporal force profile was divided into two time-segments (an initial segment and a later segment). The peak force and peak force rate during the initial time-segment, and the holding force and intra-trial variability (coefficient of variation) during the later time-segment, were measured. The results showed no differences in the peak force, peak force rate, holding force, and force variability in children compared with adults. However, the trends in the data evaluated using a segmented regression analysis showed that a breakpoint (abrupt change) consistently occurred in the late-mixed dentition group (age 9–11 yr) for most of the outcome variables. The results indicate that while the motor control strategies in children appear to be similar to those in adults, there is a shift in the oral motor developmental trend during the late-mixed dentition stage. 相似文献
93.
Parmanand Ayushi Mittal Abhishek K. Singh Aarti Katharina Achazi Chuanxiong Nie Rainer Haag Sunil K. Sharma 《RSC advances》2020,10(61):37555
A new class of non-ionic amphiphiles is synthesized using a diaryl derivative of diglycerol as a central core and functionalizing it with long alkyl chains (C-12/C-15) and monomethoxy PEG moiety (Mn: 350/550) by following a chemo-enzymatic approach. The aggregation behavior of the amphiphiles in aqueous medium is studied by using dynamic light scattering (DLS) and fluorescence spectroscopy, whereas the size and morphology of the aggregates are studied by transmission electron microscopy (TEM). A hydrophobic dye, Nile red and a hydrophobic drug, nimodipine, are used to demonstrate the nano-carrier capability of these non-ionic amphiphilic systems and the results are compared with amphiphilic analogues obtained from the triaryl derivatives of triglycerol. The in vitro controlled release of the encapsulated dye is successfully carried out in the presence of immobilized Candida antarctica lipase (Novozym 435). Furthermore, cytotoxicity data is also collected which suggests that the amphiphiles are suitable for biomedical applications.A new series of oligo-glycerol based amphiphiles have been synthesized for drug delivery. 相似文献
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Real‐time in vivo periprostatic nerve tracking using multiphoton microscopy in a rat survival surgery model: a promising pre‐clinical study for enhanced nerve‐sparing surgery 下载免费PDF全文
97.
Chandrakant M. Bokade Abhishek D. Madhura Abhay S. Bagul Subhash B. Thakre 《Nigerian medical journal》2015,56(4):287-291
Background:
Mortality due to pneumonia in children is more than any other illness. Limited data is available to predict mortality in children with pneumonia from central India.Aim:
To study predictors of mortality in children aged 1-59 months hospitalised with severe and very severe pneumonia.Materials and Methods:
Present study was observational longitudinal study that was done in a tertiary care hospital of central India. Two hundred and ninety children, aged 1-59 months, presented with severe and very severe pneumonia were enrolled in this study. Outcome and predictors of mortality were studied. Data was analysed with Chi-square test, univariate and multivariate regression analysis.Results:
Out of 270 enrolled study subjects, maximum (108, 37.24%) were belonged to 1-6-months age group. Proportion of mortality was maximum (16, 64.00%) in that age group. Overall case fatality rate was 8.62%. Among significant variables, delayed hospital referral [adjusted odds ratio (OR)-52.09, 95% confidence interval (CI)- 6.74-402.39], incomplete immunisation (OR-12.28, 95% CI-2.15-69.93), severe malnutrition (Z score < −3) (OR-15.51, 95% CI- 2.04-117.83), refusal to feed (OR- 30.57, 95% CI- 2.47-378.26), and hypoglycaemia (OR- 6.98, 95% CI- 1.05-46.30) were found significant independently on multivariate regression analysis. Conclusion: Delayed hospital referral, incomplete immunisation, severe malnutrition, refusal to feed, and hypoglycaemia were independent predictors of mortality in children with severe and very severe pneumonia. 相似文献98.
Ashish Correa Achint Patel Kinsuk Chauhan Harshil Shah Aparna Saha Mihir Dave Priti Poojary Abhishek Mishra Narender Annapureddy Shaman Dalal Ioannis Konstantinidis Renu Nimma Shiv Kumar Agarwal Lili Chan Girish Nadkarni Sean Pinney 《Journal of cardiac failure》2018,24(7):442-450
Background
Dialysis-requiring acute kidney injury (D-AKI) is a serious complication in hospitalized heart failure (HF) patients. However, data on national trends are lacking after 2002.Methods
We used the Nationwide Inpatient Sample (2002–2013) to identify HF hospitalizations with and without D-AKI. We analyzed trends in incidence, in-hospital mortality, length of stay (LoS), and cost. We calculated adjusted odds ratios (aORs) for predictors of D-AKI and for outcomes including in-hospital mortality and adverse discharge (discharge to skilled nursing facilities, nursing homes, etc).Results
We identified 11,205,743 HF hospitalizations. Across 2002–2013, the incidence of D-AKI doubled from 0.51% to 1.09%. We found male sex, younger age, African-American and Hispanic race, and various comorbidities and procedures, such as sepsis and mechanical ventilation, to be independent predictors of D-AKI in HF hospitalizations. D-AKI was associated with higher odds of in-hospital mortality (aOR 2.49, 95% confidence interval [CI] 2.36–2.63; P?<?.01) and adverse discharge (aOR 2.04, 95% CI 1.95–2.13; P?<?.01). In-hospital mortality and attributable risk of mortality due to D-AKI decreased across 2002–2013. LoS and cost also decreased across this period.Conclusions
The incidence of D-AKI in HF hospitalizations doubled across 2002–2013. Despite declining in-hospital mortality, LoS, and cost, D-AKI was associated with worse outcomes. 相似文献99.
100.
Gretja Schnell Rakesh Tripathi Jill Beyer Thomas Reisch Preethi Krishnan Liangjun Lu Tatyana Dekhtyar Coleen Hall Regis A. Vilchez Tami Pilot-Matias Christine Collins 《Antimicrobial agents and chemotherapy》2015,59(11):6807-6815
Hepatitis C virus (HCV) genotype 4 (GT4) is genetically diverse, with 17 confirmed subtypes, and comprises approximately 13% of infections worldwide. In this study, we identified GT4 subtypes by phylogenetic analysis, assessed differences in patient demographics across GT4 subtypes, examined baseline sequence variability among subtypes and the potential impact on treatment outcome, and analyzed the development of viral resistance in patients who received a regimen of ombitasvir (nonstructural protein 5A [NS5A] inhibitor) plus ritonavir-boosted paritaprevir (NS3/4A inhibitor) with or without ribavirin (RBV) for the treatment of HCV GT4 infection. Phylogenetic analysis of HCV NS3/4A, NS5A, and NS5B nucleotide sequences identified 7 subtypes (4a, 4b, 4c, 4d, 4f, 4g/4k, and 4o) among 132 patient samples. Subtype prevalence varied by country, and the distributions of patient birth cohort and race were significantly different across GT4 subtypes 4a, 4d, and non-4a/4d. Baseline amino acid variability was detected in NS5A across GT4 subtypes but had no impact on treatment outcome. Three patients experienced virologic failure and were infected with subtype 4d, and the predominant resistance-associated variants at the time of failure were D168V in NS3 and L28V in NS5A. Overall, high response rates were observed among patients infected with 7 HCV GT4 subtypes, with no impact of baseline variants on treatment outcome. GT4 subtype distribution in this study differed based on patient demographics and geography. 相似文献