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871.
872.
Kumar V. Sahu D. S. Ali N. Kumar R. Yadav S. P. Chandra G. Roy D. Maurya P. S. 《Proceedings of the National Academy of Sciences, India. Section B.》2021,91(2):373-379
Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - This experiment was conducted to evaluate the effect of zinc (Zn)-yeast supplementation on growth... 相似文献
873.
Two-dimensional transition metal dichalcogenides show great potential as promising thermoelectric materials due to their lower dimensionality, the unique density of states and quantum confinement of carriers. Here the effects of mechanical strain on the thermoelectric performances of monolayer WS2 have been investigated using density functional theory associated with semiclassical Boltzmann transport theory. The variation of the Seebeck coefficient and band gap with applied strain has followed the same type of trend. For n-type material the relaxation time scaled power factor (S2σ/τ) increases by the application of compressive strain whereas for p-type material it increases with the application of tensile strain due to valley degeneracy. A 77% increase in the power factor has been observed for the n-type material by the application of uniaxial compressive strain. A decrease in lattice thermal conductivity with the increase in temperature causes an almost 40% increase in ZT product under applied uniaxial compressive strain. From the study, it is observed that uniaxial compressive strain is more effective among all types of strain to enhance the thermoelectric performance of monolayer WS2. Such strain induced enhancement of thermoelectric properties in monolayer WS2 could open a new window for the fabrication of high-quality thermoelectric devices.Strain induced valley degeneracy results enhancement of thermoelectric properties of monolayer WS2. Electron valleys and hole valleys become degenerate by applying compressive and tensile strain, respectively. 相似文献
874.
Annette Abraham Veronika Schmidt Miriam Kaminski Dominik Stelzle Robert De Meijere Javier Bustos Priyadarshi Soumyaranjan Sahu Hector Hugo Garcia Branko Bobi Carmen Cretu Peter Chiodini Gunita Deksne Veronique Dermauw Brecht Devleesschauwer Pierre Dorny Ana Fonseca Sarah Gabriël Maria Angeles Gmez-Morales Istvn Kucsera Minerva Laranjo‐Gonzlez Chiara Trevisan Manuela Vilhena Naomi F. Walker Lorenzo Zammarchi Andrea Sylvia Winkler 《Tropical medicine & international health : TM & IH》2020,25(5):566-578
875.
Mayank D. Shah Prashant S. Kharkar Niteshkumar U. Sahu Zoya Peerzada Krutika B. Desai 《RSC advances》2019,9(69):40228
The emergence of multidrug-resistant (MDR) bacterial strains in the last decade is astonishingly alarming. Many of the widely used antibiotics have failed to exhibit clinical efficacy against such strains. Eventually we will exhaust all the resources in our antibiotic armamentarium. As a need of the hour, novel strategies are desperately required not only to curb, but also to reverse, the development of resistance in these pathogens, thereby maintaining their sensitivity towards current antibiotics. Intervention of bacterial virulence, rather than killing them, by inhibiting specific pathways/targets has emerged as a novel approach to tackle the drug resistance problem. The bacterial virulence is regulated via quorum-sensing, a cell–cell communication process precisely controlled by autoinducer molecules such as acyl homoserine lactone (AHL). The present study aimed at identifying promising quorum-sensing inhibitors in Pseudomonas aeruginosa, an opportunistic human pathogen especially associated with nosocomial infections, yielding four potential hits. Out of these, potassium 2-methoxy-4-vinylphenolate was the most potent quorum-sensing inhibitor targeting P. aeruginosa LasIR/RhlIR circuitry. It also inhibited biofilm formation, various virulence factors like LasA protease, LasB elastase and pyocyanin, and motility of bacteria like swarming and twitching.Effect of potassium 2-methoxy-4-vinylphenolate on quorum sensing in Pseudomonas aeruginosa. 相似文献
876.
Yoon YC Oh JK Oh CW Sahu D Hwang JH Cho JW 《Archives of orthopaedic and trauma surgery》2012,132(2):233-237
With the introduction of 3.5 anatomically pre-shaped plates, the rafting screw technique is gaining popularity in recent years
for the management of lateral tibial plateau fractures with articular depression. To gain access to the depressed articular
fragments, the split fragment is hinged open laterally. We elevate the depressed articular fragments to the normal level.
The defect below is filled with bone graft or its substitutes. We then close the split fragment and apply rafting screws either
through the screw holes of the plate or separately above the plate rather in a blind fashion. We therefore cannot be sure
that the rafting screws are supporting the specific elevated fragments. For this reason some surgeons place the rafting screws
from within and then close the lateral fragment over the screws. This so-called embedded rafting screw technique carries the
risk of difficulty in removal, especially in case of an infection. Here we describe the inside out rafting technique to tackle
this problem. 相似文献
877.
GS Matharu K Theivendran PB Pynsent L Jeys AM Pearson DJ Dunlop 《Annals of the Royal College of Surgeons of England》2014,96(7):530-535
Introduction
High short-term failure rates have been reported for a variety of metal-on-metal (MoM) total hip replacements (THRs) owing to adverse reactions to metal debris (ARMD). This has led to the withdrawal of certain poorly performing THRs. This study analysed the outcomes of a MoM THR system.Methods
Between 2004 and 2010, 578 uncemented MoM THRs (511 patients, mean age: 60.0 years) were implanted at one specialist centre. The THR system used consisted of the Corail® stem, Pinnacle® cup, Ultamet® liner and Articul/eze® femoral head (all DePuy, Leeds, UK). All patients were recalled for clinical review with imaging performed as necessary.Results
The mean follow-up duration was 5.0 years (range: 1.0–9.1 years). Overall, 39 hips (6.7%) in 38 patients (all 36mm femoral head size) underwent revision at a mean time of 3.5 years (range: 0.01–8.3 years) from the index THR with 30 revisions (77%) performed in women. The cumulative eight-year survival rate for all THRs was 88.9% (95% confidence interval [CI]: 78.5–93.4%), with no difference (p=0.053) between male (95.2%, 95% CI: 84.2–98.7%) and female patients (85.3%, 95% CI: 70.2–92.1%) at eight years. Seventeen revisions (44%) were performed for ARMD. There was no significant difference in absolute postoperative Oxford hip scores between men and women (p=0.608). The mean acetabular inclination in unrevised THRs was 44.0°. Forty-seven non-revised THRs (8.7%) had blood metal ion concentrations above recommended thresholds (seven had periprosthetic effusions).Conclusions
Although this MoM THR system has not failed as dramatically as other similar designs, we recommend against continued use and advise regular clinical surveillance to identify ARMD early. 相似文献878.
Comparative cytotoxicity of nanosilver in human liver HepG2 and colon Caco2 cells in culture 下载免费PDF全文
Saura C. Sahu Jiwen Zheng Lesley Graham Lynn Chen John Ihrie Jeffrey J. Yourick Robert L. Sprando 《Journal of applied toxicology : JAT》2014,34(11):1155-1166
The use of silver nanoparticles in food, food contact materials, dietary supplements and cosmetics has increased significantly owing to their antibacterial and antifungal properties. As a consequence, the need for validated rapid screening methods to assess their toxicity is necessary to ensure consumer safety. This study evaluated two widely used in vitro cell culture models, human liver HepG2 cells and human colon Caco2 cells, as tools for assessing the potential cytotoxicity of food‐ and cosmetic‐related nanoparticles. The two cell culture models were utilized to compare the potential cytotoxicity of 20‐nm silver. The average size of the silver nanoparticle determined by our transmission electron microscopy (TEM) analysis was 20.4 nm. The dynamic light scattering (DLS) analysis showed no large agglomeration of the silver nanoparticles. The concentration of the 20‐nm silver solution determined by our inductively coupled plasma–mass spectrometry (ICP‐MS) analysis was 0.962 mg ml–1. Our ICP‐MS and TEM analysis demonstrated the uptake of 20‐nm silver by both HepG2 and Caco2 cells. Cytotoxicity, determined by the Alamar Blue reduction assay, was evaluated in the nanosilver concentration range of 0.1 to 20 µg ml–1. Significant concentration‐dependent cytotoxicity of the nanosilver in HepG2 cells was observed in the concentration range of 1 to 20 µg ml–1 and at a higher concentration range of 10 to 20 µg ml–1 in Caco2 cells compared with the vehicle control. A concentration‐dependent decrease in dsDNA content was observed in both cell types exposed to nanosilver but not controls, suggesting an increase in DNA damage. The DNA damage was observed in the concentration range of 1 to 20 µg ml–1. Nanosilver‐exposed HepG2 and Caco2 cells showed no cellular oxidative stress, determined by the dichlorofluorescein assay, compared with the vehicle control in the concentration range used in this study. A concentration‐dependent decrease in mitochondria membrane potential in both nanosilver exposed cell types suggested increased mitochondria injury compared with the vehicle control. The mitochondrial injury in HepG2 cells was significant in the concentration range of 1 to 20 µg ml–1, but in Caco2 cells it was significant at a higher concentration range of 10 to 20 µg ml–1. These results indicated that HepG2 cells were more sensitive to nanosilver exposure than Caco2 cells. It is generally believed that cellular oxidative stress induces cytotoxicity of nanoparticles. However, in this study we did not detect any nanosilver‐induced oxidative stress in either cell type at the concentration range used in this study. Our results suggest that cellular oxidative stress did not play a major role in the observed cytotoxicity of nanosilver in HepG2 and Caco2 cells and that a different mechanism of nanosilver‐induced mitochondrial injury leads to the cytotoxicity. The HepG2 and Caco2 cells used this study appear to be targets for silver nanoparticles. The results of this study suggest that the differences in the mechanisms of toxicity induced by nanosilver may be largely as a consequence of the type of cells used. This differential rather than universal response of different cell types exposed to nanoparticles may play an important role in the mechanism of their toxicity. In summary, the results of this study indicate that the widely used in vitro models, HepG2 and Caco2 cells in culture, are excellent systems for screening cytotoxicity of silver nanoparticles. These long established cell culture models and simple assays used in this study can provide useful toxicity and mechanistic information that can help to better inform safety assessments of food‐ and cosmetic‐related silver nanoparticles. Published 2014. This article is a U.S. Government work and is in the public domain in the USA. 相似文献
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880.