Protective effect of hydrogen-rich saline on ischemia/reperfusion injury in rat skin flap

Objective

Skin damage induced by ischemia/reperfusion (I/R) is a multifactorial process that often occurs in plastic surgery. The mechanisms of I/R injury include hypoxia, inflammation, and oxidative damage. Hydrogen gas has been reported to alleviate cerebral I/R injury by acting as a free radical scavenger. Here, we assessed the protective effect of hydrogen-rich saline (HRS) on skin flap I/R injury.

Methods

Abdominal skin flaps of rats were elevated and ischemia was induced for 3 h; subsequently, HRS or physiological saline was administered intraperitoneally 10 min before reperfusion. On postoperative Day 5, flap survival, blood perfusion, the accumulation of reactive oxygen species (ROS), and levels of cytokines were evaluated. Histological examinations were performed to assess inflammatory cell infiltration.

Results

Skin flap survival and blood flow perfusion were improved by HRS relative to the controls. The production of malondialdehyde (MDA), an indicator of lipid peroxidation, was markedly reduced. A multiplex cytokine assay revealed that HRS reduced the elevation in the levels of inflammatory cytokines, chemokines and growth factors, with the exception of RANTES (regulated on activation, normal T-cell expressed and secreted) growth factor. HRS treatment also reduced inflammatory cell infiltration induced by I/R injury.

Conclusions

Our findings suggest that HRS mitigates I/R injury by decreasing inflammation and, therefore, has the potential for application as a therapy for improving skin flap survival.     

Influence of HbA1c on short-term blood pressure variability in type 2 diabetic patients with diabetic nephropathy

The aim of this study was to understand the characteristics of blood pressure(BP)variability in subjects with diabetic nephropathy(DN),and identify the probable predictors affecting BP variability.Fifty-one chronic kidney disease(CKD)-hypertensive patients without diabetes(NDN group)and sixty type 2 diabetic patients with overt DN(DN group)were enrolled in this study.The values of short-term BP variability were obtained from 24 h ambulatory BP monitoring(ABPM).Variance analysis or nonparametric analysis revealed that 24-h systolic BP variability and nighttime systolic BP variability of the DN group were significantly higher than those of the NDN group[(12.23±3.66)vs.(10.74±3.83)mmHg,P<0.05;(11.23±4.82)vs.(9.48±3.69)mmHg,P<0.05].Then the patients of the DN group were divided into two groups according to glycated hemoglobin(HbA1c)level:Group A(HbA1c<7%)and Group B(HbA1c≥7%),and the t-test showed that patients in Group B had larger 24-h diastolic,daytime diastolic,and nighttime systolic/diastolic BP variability compared with Group A.In the DN group,partial correlation analysis revealed that HbA1c exhibited a strong association with 24-h diastolic,daytime diastolic,nighttime systolic and diastolic BP variability(P<0.001,P<0.001,P<0.05,and P<0.001,respectively).Taken together,larger short-term BP variability was detected in hypertensive type 2 diabetic patients with overt nephropathy and renal insufficiency.It may imply that the optimal BP variability level could benefit from a better glycaemic control.     

Influence of induced ciprofloxacin resistance on efflux pump activity of Klebsiella pneumoniae

Objective

The efflux pump (EP) is one of the major mechanisms of antibiotic resistance in Klebsiella pneumoniae. However, there are few reports on the effect of the abuse of antibiotic use on the activity of EPs. To determine whether the use of low efficacy antibiotics has any effect on the activity of EPs and induces drug resistance in K. pneumoniae, we investigated the effect of ciprofloxacin on the activity of EPs in K. pneumoniae strains.

Methods

Sixteen susceptible K. pneumoniae strains were isolated from patients and their minimum inhibitory concentrations (MICs) of ciprofloxacin were measured in the absence and presence of the pump inhibitor carbonyl cyanide m-chlorophenyl hydrazone (CCCP). The strains were then induced with a gradient of ciprofloxacin until the MICs of the strains showed no further increase, to obtain induced resistant strains. The EP activities of the strains before and after induction were compared using EP inhibition and ethidium bromide (EtBr) accumulation assays.

Results

The MIC values of the strains were 16–256 times higher after induction than before induction. In the presence of CCCP, the MIC values of 50% of the induced strains were 2–4-fold lower than that in the absence of this inhibitor. The EtBr accumulation assay showed that the fluorescence of EtBr in the induced cells was lower than that in the cells before induction.

Conclusions

EPs are widespread in susceptible and drug-resistant K. pneumoniae strains. Induction with ciprofloxacin may increase the activity of EPs in K. pneumoniae. The EtBr accumulation assay is more sensitive than the EP inhibition assay in evaluating the activity of EPs in K. pneumoniae.     

美国小城市公共图书馆管理与服务研究

文章主要针对美国的小城市公共图书馆的管理机制进行探索,分别就图书馆委员会、图书馆馆员(工作人员)机制、财政机制等进行了分析。认为美国公共图书馆管理机制发达而完善的原因在于成熟的民主文化、完善的法律支持等因素。     

绘制"东突"恐怖主义网络

中国的恐怖主义威胁主要来源于国内外的"东突"恐怖组织,这一组织具有特殊的历史根源.本文主要从其犯罪历史、攻击方法及行动方面出发,构建了其网络拓扑结构模型,描述了行动、成员特性,分析了其网络结构特征.分析结果揭示:"东突"恐怖组织的受到多种因素的影响,如地理位置、网络边界等.研究发现"东突"恐怖组织的网络结构是一个树形结构,其表现为没有环,并且具有等级结构.最后,我们根据"东突"恐怖组织未来的演化趋势,提出了一些谨慎的对策与建议.     

基于高质量反馈源的XML查询扩展

有效避免伪反馈的"查询主题漂移"主要需要解决两大问题,一是如何确定相关文档,形成较高质量的伪相关文档集,另一个是在伪相关文档集里如何挑选扩展信息.本文主要研究在获取了高质量伪相关文档集合的基础上如何有效进行XML查询扩展.针对XML文档的特点,提出了扩展向量空间模型的查询词扩展方法.实验结果表明,与初始查询和传统的词项扩展方法相比,该扩展方法更能获得与用户查询意图相关的扩展信息,更能有效地提高检索质量和性能.     

To name or not to name: a cross-cultural comparison of on-air attribution in US and Chinese TV news

This study investigates the Sino-US difference in the journalistic practice of providing on-air attribution for those interviewed in television news. Through a content analysis, this study compares how CBS News, a premier US TV network, and CCTV, China's most watched network, attributed their interviewees with on-screen name credits (names, titles and affiliations). The findings show that US journalists were more likely to provide on-screen name credits than their Chinese colleagues who, in turn, were more likely to give credits to interviewees who were older, male and government officials. This study should contribute to a better understanding of how cultural values and political ideologies may affect the way interviewees are treated in television news.     

Gaming motivations,avatar-self identification and symptoms of online game addiction

This study conducted a survey of 217 adult game players in Hong Kong to explore the effects of gaming motivations and avatar-self identification on symptoms of online game addiction. Results show that avatar-self identification is positively associated with the problems and salience dimension as well as the uncontrollable game-play dimension of game addiction. The motivation to relax is positively related to perceived avatar-self identification and uncontrollable play; the motivation to socialize in online games is positively linked with the avatar-self identification and both symptoms of online game addiction. The motivation to escape is positively related to the symptom of problems and salience. The drive to achieve virtual accomplishment in online games is negatively associated with the problem caused by gameplay and the salience of online games.     

建国后高校文科外文文献的发展状况与未来保障研究

以高校人文社科外文文献为重点,概述建国以来我国高校的文献收藏情况、对人文社会科学研究的支撑程度和满足水平、以及面对问题采取的保障与宏观建设方案.     

浅析“90后大学生”的心理特征

提到"90后",要追溯到"80后"。"90后大学生"的提出,源于近年来"90后"青少年成为大学生的主要组成部分。本文将针对"90后大学生"的心理特征展开论述。