Involvement of peroxiredoxin I in protecting cells from radiation-induced death

Peroxiredoxin I (Prx-I), a key member of the peroxiredoxin family, reduces peroxides and equivalents through the thioredoxin system. Our previous work has shown that expression of Prx-I in mammalian cells increases following ionizing radiation (IR), indicating that Prx-I actively responds to IR-induced reactive oxygen species (ROS) and suggesting that Prx-I plays an important role in protecting cells from IR-induced death. To test this hypothesis, we suppressed the expression of Prx-I in SW480 cells by RNA interference. Our results show that IR induces the expression of Prx-I in SW480 cells in a dose- and time-dependent manner. The recombinant siRNA vector targeting Prx-I dramatically reduced the expression of Prx-I in SW480 cells. When Prx-I was knocked down in SW480 cells, the cells exhibited a decreased growth rate, a reduced antioxidant capability following IR and became more sensitive to IR-induced apoptosis. Together, our results demonstrate that Prx-I plays an important role in protecting cells from IR-induced cell death, which might be through scavenging IR-induced ROS in the cells.     

Contributions of Neighborhood Parks to Physical Activity in High-Poverty Urban Neighborhoods

Neighborhood parks are important venues for the urban population to do moderate-to-vigorous physical activity in leisure time. Parks can be particularly important for low-income neighborhoods, whose residents suffer from high rates of chronic diseases and may have less access to fee-based fitness exercise facilities. This study assessed the contribution of parks to local populations’ physical activity in 48 high-poverty neighborhoods in the city of Los Angeles, using systematic observation of park use and surveys of park users and residents conducted between 2013 and 2015. We found that parks accounted for approximately 2.1% (between-park SD?=?1.4%) of moderate physical activity time and 3.1% (between-park SD?=?2.1%) of vigorous physical activity time of the local population, both of which were notably lower than the city-level average previously reported. Parks’ contribution to physical activity was positively associated with park size (β?=?0.13, p?<?0.0001) and negatively associated with poverty (β?=???0.10, p?<?0.0001) and local population density (β?=???0.25, p?=?0.005). Parks in high-poverty neighborhoods in Los Angeles are underutilized, and more efforts are needed to fully realize their potential for population health.     

Everyday wild: Urban natural areas,health, and well-being

Cities are increasingly home to the world's population. Creating healthy and vibrant cities is one way to positively contribute to the health of populations. Parks and green spaces in cities contribute many health benefits. This case study explored the perceived health and well-being effects of access to Natural Area Parks in Edmonton, Canada through photovoice interviews with 33 participants. The research found the wild aspects of the parks of particular importance. Critically, the therapeutic value of the park emerged from the totality of the experience rather than from its individual components. Access to wilderness increased opportunities for relaxation, deep connection, and reflection.     

A tracer method for quantifying contamination of building supply air: reentrainment of laboratory hood exhausts

A method is described for quantifying the reentrainment of exhaust air contaminants into a building's fresh-air supply system. The method relies on the "tracer" gas, sulfur hexafluoride (SF6), which Is detected by infrared (IR) absorption analysis. This method of analysis differs from the conventional gas chromatography, electron capture detection method due to the MIRAN-1 A's portability, direct-reading capabilities, ease of operation and modest cost. Specific instrument settings for the MIRAN-1 A are given such that detection of SF6 will be optimized without interference. Calculations for quantifying reentrainment are presented and discussed for the "worst case" reentrainment observed.     

Planning for health: A community-based spatial analysis of park availability and chronic disease across the lifespan

The purpose of this study was to explore the spatial relationship between park availability and chronic health conditions (CHCs) across age groups in Kansas City, MO. Multinomial logistic regression examined the association between having a park within one-half mile from home and the likelihood of having 0, 1, or 2 or more CHCs. Among respondents aged 40–59, those without a park within one-half mile from home were more than twice as likely to have 2 or more CHCs compared to respondents that had a park nearby. Parks may be an important protective factor for chronic diseases, especially among middle-aged adults among whom access to neighborhood recreational environments may be particularly important.     

Assessment of Respirable Crystalline Silica Analysis Using Proficiency Analytical Testing Results from 2003–2013

Analysis of Proficiency Analytical Testing (PAT) results between 2003 and 2013 suggest that the variation in respirable crystalline silica analysis is much smaller today than it was in the period 1990–1998, partly because of a change in sample production procedure and because the colorimetric method has been phased out, although quality improvements in the x-ray diffraction (XRD) or infrared (IR) methods may have also played a role. There is no practical difference between laboratories using XRD or IR methods or between laboratories which are accredited or those which are not. Reference laboratory means (assigned values) are not different from the means of all participants across the current range of mass loading, although there is a small difference in variance in the ratios of all participants to reference laboratory means based on method because the reference laboratories are much more likely to use XRD than are the others. Matrix interference does not lead to biases or substantially larger variances for either XRD or IR methods. Data from proficiency test sample analyses that include results from poorly performing laboratories should not be used to determine the validity of a method. PAT samples are not produced below 40 μg and variance may increase with lower masses, although this is not particularly predictable. PAT data from lower mass loadings will be required to evaluate analytical performance if exposure limits are lowered without change in sampling method. Task-specific exposure measurements for periods shorter than a full shift typically result in lower mass loadings and the quality of these analyses would also be better assured from being within the range of PAT mass loadings. High flow rate cyclones, whose performance has been validated, can be used to obtain higher mass loadings in environments of lower concentrations or where shorter sampling times are desired.     

医疗侵权损害赔偿"双轨制"法律适用原则的困惑与反思

现行的医疗侵权损害赔偿"双轨制"原则倍受争议;医疗行业的独特性决定了医患关系是受到国家干预的民事法律关系,《医疗事故处理条例》是国家对医疗损害民事赔偿进行行政干预的产物;医疗纠纷中传统的"主观过错"的归责理论难以对医疗过错准确定性,相应导致医疗事故(过失)与非医疗事故(过失)损害赔偿法律适用的冲突。"双轨制"原则的初衷实系将可容许的合理医疗损害与不可容许的恶性医疗损害予以分类区别对待,只有确立"客观过错"的归责理论才能凸显"双轨制"原则的现实合理性。     

Determining of crystalline silica in respirable dust samples by infrared spectrophotometry in the presence of interferences

Infrared Spectrophotometry (IR) is now widely used to determine crystalline silica in industrial dust samples. Though the IR method has many advantages when dealing with respirable dust samples, some serious analytical errors are often caused by interference minerals contamination. These minerals have a characteristic absorption band corresponding in position to the analytical peak for crystalline silica. In this paper, six typical interference minerals (Kaolinite, Mullite, Muscovite, Pyrophyllite, Montmorillonite and Amorphous silica) were pre-size controlled to respirable range and their infrared spectra were measured by means of an FT-IR with the well-known potassium bromide tablet technique. The effects of these interference minerals on the Japanese OEL or the administrative control level for respirable dust which depend on the silica content were calculated and expressed in figures. The measured absorption coefficients of the interference minerals and quartz were 1.36-6.98 Abs/mg and 24.46 Abs/mg, respectively. The absorption band height ratios of each interference minerals were also measured. Then the efficiency and applicability of two spectrum correction methods for the interference minerals, absorbance ratio method and difference spectrum method were examined by using artificially mixed samples (standard interference mineral + standard quartz). By comparing the quantifying results for the mixture samples, it was revealed that the interfered spectra were almost corrected successfully when using the difference spectrum method, whereas correction by the absorbance ratio method resulted in apparent negative errors. Furthermore, the difference spectrum method was proven to be superior to the absorbance ratio method in applicability.     

The Prospects for National Health Insurance Reform

This article explores the unequal access to health care in the context of efforts by the American Medical Association (AMA) and its allies to maintain a market-maximizing health care system. The coalition between the AMA and its traditional allies is breaking down, in part, because of converging developments creating an atmosphere which may be more conductive to national health care reform and the development of a reformed health care delivery system that will be accessible, adequate, and equitable in meeting the health care and related social service needs of the American people.     

The prospects for national health insurance reform

This article explores the unequal access to health care in the context of efforts by the American Medical Association (AMA) and its allies to maintain a market-maximizing health care system. The coalition between the AMA and its traditional allies is breaking down, in part, because of converging developments creating an atmosphere which may be more conducive to national health care reform and the development of a reformed health care delivery system that will be accessible, adequate, and equitable in meeting the health care and related social service needs of the American people.     

Evaluating Health Advice in a Web 2.0 Environment: The Impact of Multiple User-Generated Factors on HIV Advice Perceptions

ABSTRACT

Unlike traditional media, social media systems often present information of different types from different kinds of contributors within a single message pane, a juxtaposition of potential influences that challenges traditional health communication processing. One type of social media system, question-and-answer advice systems, provides peers’ answers to health-related questions, which yet other peers read and rate. Responses may appear good or bad, responders may claim expertise, and others’ aggregated evaluations of an answer’s usefulness may affect readers’ judgments. An experiment explored how answer feasibility, expertise claims, and user-generated ratings affected readers’ assessments of advice about anonymous HIV testing. Results extend the heuristic–systematic model of persuasion (Chaiken, 1980) and warranting theory (Walther & Parks, 2002). Information that is generally associated with both systematic and heuristic processes influenced readers’ evaluations. Moreover, content-level cues affected judgments about message sources unexpectedly. When conflicting cues were present, cues with greater warranting value (consensus user-generated ratings) had greater influence on outcomes than less warranted cues (self-promoted expertise). Findings present a challenge to health professionals’ concerns about the reliability of online health information systems.     

HIV prophylaxis is deemed pertinent evidence in rape trial

A Georgia trial judge acted properly in admitting into evidence the fact that a rape victim took an antiretroviral drug for six months following her attack. The victim, identified as J. A., was raped by an HIV-positive defendant, identified as Parks. Parks was found guilty of battery and aggravated sodomy, and similar charges related to another victim, both of whom he also threatened with a shotgun. The Georgia Court of Appeals held that disclosing J. A.'s prophylactic treatment with AZT demonstrated that she would not have had consensual unprotected sex if she knew Parks was HIV-positive.     

Sources and fate of chiral organochlorine pesticides in western U.S. National Park ecosystems

The enantiomer fractions (EFs) of alpha-hexachlorocyclohexane (α-HCH), cis-, trans-, and oxychlordane, and heptachlor epoxide were measured in 73 snow, fish, and sediment samples collected from remote lake catchments, over a wide range of latitudes, in seven western U.S. National Parks/Preserves to investigate their sources, fate, accumulation and biotransformation in these ecosystems. The present study is novel because these lakes had no inflow or outflow, and the measurement of chiral organochlorine pesticides (OCPs) EFs in snowpack from these lake catchments provided a better understanding of the OCP sources in the western United States, whereas their measurement in fish and sediment provided a better understanding of their biotic transformations within the lake catchments. Nonracemic α-HCH was measured in seasonal snowpack collected from continental U.S. National Parks, and racemic α-HCH was measured in seasonal snowpack collected from the Alaskan parks, suggesting the influence of regional sources to the continental U.S. parks and long-range sources to the Alaskan parks. The α-HCH EFs measured in trout collected from the lake catchments were similar to the α-HCH EFs measured in seasonal snowpack collected from the same lake catchments, suggesting that these fish did not biotransform α-HCH enantioselectively. Racemic cis-chlordane was measured in seasonal snowpack and sediment collected from Sequoia, indicating that it had not undergone significant enantioselective biotransformation in urban soils since its use as a termiticide in the surrounding urban areas. However, nonracemic cis-chlordane was measured in seasonal snowpack and sediments from the Rocky Mountains, suggesting that cis-chlordane does undergo enantioselective biotransformation in agricultural soils. The trout from these lakes showed preferential biotransformation of the (+)-enantiomer of cis-chlordane and the (-)-enantiomer of trans-chlordane.     

Apelin在多囊卵巢综合征中的研究进展

多囊卵巢综合征(PCOS)是最常见的女性内分泌疾病,以慢性无排卵和高雄激素血症为特征,其病因复杂,临床表现高度异质,不仅影响女性生殖和内分泌系统,还常伴随多种代谢异常,包括胰岛素抵抗、高胰岛素血症、肥胖等.Apelin是脂肪因子家族新成员,是由脂肪细胞分泌的一类活性肽激素,主要参与体液平衡、食物摄入、胰岛素分泌、能量代...     

Momordica charantia (bitter melon) reduces plasma apolipoprotein B-100 and increases hepatic insulin receptor substrate and phosphoinositide-3 kinase interactions

Aqueous extracts or juice from unripened fruit of Momordica charantia (bitter melon) has traditionally been used in the treatment of diabetes and its complications. Insulin resistance is characterized by significant down-regulation of hepatic insulin signalling as documented by attenuated phosphorylation of insulin receptor (IR), IR substrates 1 and 2, phosphoinositide-3 kinase, protein kinase B, and over-expression of phosphotyrosine phosphatase 1B. We recently demonstrated that bitter melon juice (BMJ) is a potent inhibitor of apoB secretion and TAG synthesis and secretion in human hepatoma cells, HepG2, that may be involved in plasma lipid- and VLDL-lowering effects observed in animal studies. The aim of this study was to evaluate the effects of BMJ on plasma apoB levels and hepatic insulin signalling cascade in mice fed high-fat diet (HFD). Female C57BL/6 mice (4-6 weeks old) were randomized into three groups receiving regular rodent chow, HFD and HFD+BMJ. The data indicate that BMJ not only improves glucose and insulin tolerance but also lowers plasma apoB-100 and apoB-48 in HFD-fed mice as well as modulates the phosphorylation status of IR and its downstream signalling molecules. Investigating the biochemical and molecular mechanisms involved in amelioration of diabetic dyslipidaemia by BMJ may lead to identification of new molecular targets for dietary/alternative therapies.     

结膜Parks切口联合表面麻醉在斜视手术中的应用

目的观察结膜Parks切口联合表面麻醉下进行斜视手术的效果。方法斜视患者136例,表面麻醉剂0．4％盐酸奥布卡因滴眼液术前3次点术眼,常规行结膜Parks切口。观察麻醉效果、术中、术后并发症及手术效果。结果麻醉效果I级者98例（72．05％）,Ⅱ级者38例（27．95％）,Ⅲ级者0例;术后睑裂区外观正常,美容效果显著,未出现持续不退的结膜充血、结膜囊肿、结膜瘢痕等并发症。结论结膜Parks切口联合表面麻醉剂的斜视手术安全可行、操作简便、手术快捷、并发症少、美容效果好。     

Doctor who lost her job due to HIV allowed to continue suit

U.S. District Judge Wayne R. Anderson rejected as premature a defense motion to dismiss an Americans with Disabilities Act (ADA) claim filed by a physician who states she was denied employment at the Family Health Care Associates Clinic after she was diagnosed as HIV-positive. The judge said that depositions will have to be taken before he is willing to accept arguments that Dr. Bari Parks posed too great a risk to the health and safety of her patients. Courts have held that HIV-positive surgeons and surgical technicians do not qualify for protection of the ADA or the Rehabilitation Act because their condition constitutes a direct threat. Parks was to begin work as an OB/GYN specialist at a clinic but was hospitalized and diagnosed with HIV. At first her employer assured her that health care expenses would be insured and the illness would not affect her employment. On the day she was cleared to return to work she was told that her starting date would be postponed and she would have to inform all patients that she was HIV-positive. After six-weeks with no response about her employment, Parks filed a complaint with the Equal Employment Opportunity Commission (EEOC). The EEOC issued her a right-to-sue letter in 1996.     

自适应噪声抵消在抑制高频电刀对心电监护仪干扰中的应用研究

本文讨论了如何利用自适应噪声抵消去除高频电刀工作时对心电监护波形的干扰。本课题基于高频电刀干扰成分的研究，采用了滤波系统去除高频成分的干扰；利用了自适应噪声抵消系统实现对噪声的跟踪、去除。并利用MATLAB语言对抑制措施进行动态仿真，验证了抑制措施的可行性。     

美国的专科医师制度探析及中国专科医师制度建立的思考

美国的专科医师制度发展经历了100年,专科医师制度关注医学教育的发展,制定专科医师认证和再认证的标准,通过专科准入和再认证制度,提高了专科医师的准入门槛,保证了医生的终身学习,为患者提供安全、优质的医疗服务。我国的专科医师制度的设计既要借鉴发达国家的经验,又要结合自身的实际情况,发挥专业学会和学术团体的作用,逐步建立专科医师培训制度,规范专科准入标准,切实促进医生的终身学习、持续进步。     

早产儿高胆红素血症对神经系统的远期影响及早期干预的研究

对1985～1996年收治的早产儿伴黄疸308例按不同血清总胆红素浓度分组,进行早期光疗和行为干预,并分别在2岁、5岁时随访发现,未干预组神经系统异常47.7％,干预组34.2％,两组有显著差异。异常顺位为精神发育迟滞、听力异常、运动落后、语言障碍和视觉障碍。总胆红素在137μmol/L以上时远期神经系统异常显著增加。提示早产儿高胆红素血症对神经系统的远期影响显著,早期干预能明显降低神经系统异常的发生率。