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61.
《Free radical research》2013,47(10):781-792
Abstract

The relevance of reactive oxygen species (ROS) production relies on the dual role shown by these molecules in aerobes. ROS are known to modulate several physiological phenomena, such as immune response and cell growth and differentiation; on the other hand, uncontrolled ROS production may cause important tissue and cell damage, such as deoxyribonucleic acid oxidation, lipid peroxidation, and protein carbonylation. The manganese superoxide dismutase (MnSOD) antioxidant enzyme affords the major defense against ROS within the mitochondria, which is considered the main ROS production locus in aerobes. Structural and/or functional single nucleotide polymorphisms (SNP) within the MnSOD encoding gene may be relevant for ROS detoxification. Specifically, the MnSOD Ala16Val SNP has been shown to alter the enzyme localization and mitochondrial transportation, affecting the redox status balance. Oxidative stress may contribute to the development of type 2 diabetes, cardiovascular diseases, various inflammatory conditions, or cancer. The Ala16Val MnSOD SNP has been associated with these and other chronic diseases; however, inconsistent findings between studies have made difficult drawing definitive conclusions. Environmental factors, such as dietary antioxidant intake and exercise have been shown to affect ROS metabolism through antioxidant enzyme regulation and may contribute to explain inconsistencies in the literature. Nevertheless, whether environmental factors may be associated to the Ala16Val genotypes in human diseases still needs to be clarified.  相似文献   
62.
This study examined the bioaccumulation of key metals and other contaminants (SO4, F, Na, K, Ca, Mg, P, Si, Fe, Mn, Zn, Ni, Co, Cu, and Cd) by seaweeds from the Egyptian Mediterranean Sea coast and their risk to human health. Bioaccumulation factor calculations indicated that S, F, Na, K, Zn, Cu, and Cd had high seaweed uptake and this referred to the potential pollution of the coastal area. Multivariate analysis of the studied contaminants confirmed the bioaccumulation factor results as well as the physiological processes in seaweeds. Human health risk assessment of F, Mn, Zn, Ni, Cu, and Cd was conducted using hazard quotient (HQ) and incremental lifetime cancer risk (ILCR) analyses. The carcinogenic assessment of sediments and ingestion of seaweeds using ILCR calculations revealed that Mn, Ni, and Cd in sediments and F and Zn in seaweeds require remedial action in order to reduce their human health risks. Additionally, HQ calculations for the contaminants in seaweeds and reference to toxicological references values from different agencies revealed that F and Co present high human health risk effects. Consequently, the potential public health risks from dietary exposure to hazardous contaminants in seaweeds must be continually subjected to research, regulation, and debate.  相似文献   
63.
Somatic cell nuclear transfer (SCNT) research, otherwise known as therapeutic cloning, requires large numbers of research oocytes, placing pressure on an already limited supply. In the UK, Canada, Australia, Singapore and most of Western Europe, oocytes are made available through modestly reimbursed donation, and, owing to the onerous nature of donation, the existing demand for reproductive oocytes far outstrips availability. SCNT research will place this system under even greater pressure. This paper investigates the growth in a global market for oocytes, where transnational IVF clinics broker sales between generally poor, female vendors and wealthy purchasers, beyond the borders of national regulation, and with little in the way of clinical or bioethical scrutiny. It considers the possible impact that SCNT research will have on this global market. It argues that oocyte vending could be understood as a kind of reproductive labor in the bioeconomy, and suggests some ways to improve the protection, security and power of vendors.  相似文献   
64.
Zebrafish larvae provide models of muscle development, muscle disease and muscle-related chemical toxicity, but related studies often lack functional measures of muscle health. In this video article, we demonstrate a method to measure force generation during contraction of zebrafish larval trunk muscle. Force measurements are accomplished by placing an anesthetized larva into a chamber filled with a salt solution. The anterior end of the larva is tied to a force transducer and the posterior end of the larva is tied to a length controller. An isometric twitch contraction is elicited by electric field stimulation and the force response is recorded for analysis. Force generation during contraction provides a measure of overall muscle health and specifically provides a measure of muscle function. Although we describe this technique for use with wild-type larvae, this method can be used with genetically modified larvae or with larvae treated with drugs or toxicants, to characterize muscle disease models and evaluate treatments, or to study muscle development, injury, or chemical toxicity.  相似文献   
65.
目的:评估财经类院校贫困生心理状况,探讨财经类院校贫困生的心理状况与述情障碍的关系,为更好解决贫困生的心理问题提供依据。方法:对298名贫困学生进行症状自评量表(SymptomChecklist-90,SCL-90)多伦多述情障碍量表(Twenty-ItemTorontoAlexithymiaScale,TAS.20)的测量并与320名非贫困生对照组的结果进行比较。结果:①贫困生组的抑郁、焦虑、人际关系敏感、精神病性、偏执因子分及SCL.90总分因子高于对照组,贫困生组的F1因子明显高于对照组;②述情障碍组SCL-90总分和各因子得分明显高于非述情组;③述情量表总分及各因子分与症状自评量表总分及各因子分显著相关(P〈0.01或P〈0.05)。结论:①与非贫困学生相比,贫困生具有较多的心身症状,主要表现在抑郁、焦虑、人际关系敏感、精神病性、偏执。②述情障碍与心理健康密切相关,述情障碍个体倾向于更容易出现心身症状。③F1(缺乏识别情感的能力)是一个较其它因子更敏感的述情障碍的鉴定指标。  相似文献   
66.
Iodine deficiency is a factor that may compromise child development, but is not the only one. Other health determinants, some of them outside the healthcare system, are able to influence development. Fighting iodine deficiency may be a pragmatic and useful strategy if it is found to be not maleficent, beneficial to health, and cost-effective, and does not make us lose the notion that child development goes beyond psychomotor or cognitive performance. This article analyzes such constraints from a critical point of view.  相似文献   
67.
目的:调查入伍新兵心理卫生服务状况及对心理卫生服务的需求。方法:采用质性研究和量性研究相结合的方法,对42名入伍新兵作半结构性访谈,编制《部队心理卫生服务状况和需求》调查表,采用调查表对1609名新兵进行调查。结果:9.4%的新兵心理健康知识比较了解;接近半数新兵(43.5%)对心理健康知识很感兴趣;新兵获取心理知识的途径依次为网络、心理知识讲座、报刊杂志、广播电视、面对面咨询;新兵最期望获得的心理知识依次为如何调节自己的情绪、如何建立良好的人际关系、如何塑造自己的个性和常见的心理障碍表现;新兵认为最有帮助的心理服务形式依次为一对一心理咨询、心理知识讲座、心理测验和团体心理活动;只有7.7%的新兵接受过心理卫生服务。结论:新兵对心理健康知识感兴趣,但认知度和利用度均较低,应通过网络、心理知识讲座等方式普及新兵需要的心理健康知识。  相似文献   
68.
Synthetic biology (SynBio) is a global endeavour with research and development programs in many countries, and due (in part) to its multi-use characteristics it has potential to improve global health in the area of vaccine development, diagnostics, drug synthesis, and the detection and remediation of environmental toxins. However, SynBio will also concurrently require global governance. Here we present what we have learnt from the articles in this Special Issue, and the workshop we hosted in The Hague in February of 2012 on SynBio, global health, and global governance that generated many of the papers appearing here. Importantly we take the notion of ‘responsible research and innovation’ as a guiding perspective. In doing so our understanding of governance is one that shifts its focus from preventing risks and other potential negative implications, and instead is concerned with institutions and practices involved in the inclusive steering of science and technology towards socially desirable outcomes. We first provide a brief overview of the notion of global health, and SynBio’s relation to global health issues. The core of the paper explores some of the dynamics involved in fostering SynBio’s global health pursuits; paying particular attention to of intellectual property, incentives, and commercialization regimes. We then examines how DIYbio, Interactive Learning and Action, and road-mapping activities can be seen as positive and productive forms of governance that can lead to more inclusive SynBio global health research programs.  相似文献   
69.
ObjectivesTo analyze differences by age group in anxiety, depression, loneliness and comorbid anxiety and depression in young people, middle aged adults and older adults during the lock-down period at home due to the COVID-19 pandemic, and to explore the association between negative self-perceptions of aging and psychological symptoms controlling by age group.MethodParticipants are 1501 people (age range 18 to 88 years). Anxiety, sadness, loneliness and self-perceptions of aging were assessed. The sample was divided according to the age group and quartiles (lower, intermediate levels, and higher) of anxiety, sadness, loneliness and self-perceptions of aging.ResultsOlder adults reported lower levels of anxiety and sadness than middle aged adults, and middle aged adults reported lower levels than younger participants. Middle aged adults reported the lowest loneliness, followed by older adults and younger participants. For each age group, those with more negative self-perceptions of aging reported higher anxiety, sadness and loneliness. More comorbid anxiety and sadness was found in younger adults and less in older adults; more depressed participants in the middle aged group, and more older adults and less younger participants were found in the group with the lowest levels of anxiety and sadness. For all the age groups, participants with high levels of comorbid anxiety and sadness are those who report the highest scores in negative self-perceptions of aging.ConclusionsOlder adults reported lower psychological anxiety, sadness and loneliness than the other age groups. Having negative self-perceptions of aging damage psychological health irrespective of the chronological age.  相似文献   
70.
1. The ideal conditions for a parasite are typically found with its preferred host. However, prior to transmission to a naïve host and successful infection, a parasite may have to withstand extrinsic environmental conditions. Some parasites have adapted to time away from hosts, for example, by co-opting vectors or by having drought-resistant growth stages. However, other parasites may have no obvious adaptations to persist during prolonged transmission cycles. Consequently, the environment may detrimentally impact parasite fitness and ultimately epidemiology. 2. Here, we investigate the impact of nectar-realistic sugar concentrations on the ability of the trypanosome parasite Crithidia bombi, which may be transmitted between conspecifics at flowers, to infect its bumblebee host Bombus terrestris and to reproduce during the infection (parasitaemia). Our results show, following 30 min exposure to our experimental nectars that as sugar concentration increases, infection prevalence and parasitaemia decrease. This is likely due to the increased osmotic stress C. bombi experiences in high sugar, aqueous environments. 3. Consequently, if C. bombi transmission is facilitated by nectar or a high-sugar environment, it may have a negative impact on parasite fitness.  相似文献   
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