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1.
《Free radical research》2013,47(8):880-887
Abstract

Obesity has become a worldwide epidemic that leads to many serious weight-related disorders. Recently, infection by viruses has been proposed as a possible cause of the obesity epidemic. Of the many viruses screened, adenovirus 36 has been found to be a strong candidate virus that is associated with obesity, based on evidence in various model systems as well as clinical data. The mechanism of how the adenovirus could lead to obesity is not known and this paper proposes some new insights into how oxidative stress could be a possible mechanism of how adenovirus might lead to obesity. This paper reviews the relevant literature of both the effect of adenovirus on cells' anti-oxidant response and the link between obesity and oxidative stress.  相似文献   

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BackgroundSeveral studies have reported a seasonal trend in the diagnosis of childhood cancer suggesting seasonal factors such as infection. The present study aimed to analyze the diagnosis pattern of childhood malignant diseases using public health data, and to compare this pattern with seasonal viral infection trends.MethodUsing the open data source of the Health Insurance Review and Assessment Service, we extracted data regarding all patients under 21 years of age and who had any cancer, aplastic anemia or myelodysplastic syndrome between September 2009 and December 2013. The positive detection rates of 11 viruses was collected from the surveillance data of Korea Centers for Disease Control and Prevention, and seasonality analysis were conducted with both data.ResultsIn total, 9085 patients were diagnosed with malignant disease during the study period; there were about 175 new cases per month on average. Monthly stacked time series by year showed an apparent seasonal variation with the highest monthly average in January as 236, and the lowest in September as 120. In winter, significantly more patients were diagnosed with acute lymphoblastic leukemia, acute myeloid leukemia, neuroblastoma, and Hodgkin’s lymphoma than in other seasons. There was a temporal correlation with the diagnostic trends of several diseases and the prevalence of recent human parainfluenza virus.ConclusionThis study tentatively suggests that the diagnosis of childhood malignancy follows a seasonal trend in Korea, and has a possible correlation with viral prevalence in several diseases. Further long-term analysis of epidemiological data is needed to explore possible causality.  相似文献   

4.
Communication     
Abstract

In studying the effect of father's education on child's cognitive ability, we find that some models of analysis yield a negative effect, which does not seem plausible according to our current understanding of the nature of the two variables. Two new models are proposed to take account of the biological relationships between parents and children. The analyses based on these new models show a positive effect of father's education on child's IQ scores. While the results of the proposed models become more plausible, it cannot be claimed as “correct,” because there is no conclusive and permanent “proof in empirical sciences.  相似文献   

5.
BackgroundThere is a growing body of evidence associating microRNAs (miRNAs) with human diseases. MiRNAs are new key players in the disease paradigm demonstrating roles in several human diseases. The functional association between miRNAs and diseases remains largely unclear and far from complete. With the advent of high-throughput functional genomics techniques that infer genes and biological pathways dysregulted in diseases, it is now possible to infer functional association between diseases and biological molecules by integrating disparate biological information.ResultsHere, we first used Lasso regression model to identify miRNAs associated with disease signature as a proof of concept. Then we proposed an integrated approach that uses disease-gene associations from microarray experiments and text mining, and miRNA-gene association from computational predictions and protein networks to build functional associations network between miRNAs and diseases. The findings of the proposed model were validated against gold standard datasets using ROC analysis and results were promising (AUC=0.81). Our protein network-based approach discovered 19 new functional associations between prostate cancer and miRNAs. The new 19 associations were validated using miRNA expression data and clinical profiles and showed to act as diagnostic and prognostic prostate biomarkers. The proposed integrated approach allowed us to reconstruct functional associations between miRNAs and human diseases and uncovered functional roles of newly discovered miRNAs.ConclusionsLasso regression was used to find associations between diseases and miRNAs using their gene signature. Defining miRNA gene signature by integrating the downstream effect of miRNAs demonstrated better performance than the miRNA signature alone. Integrating biological networks and multiple data to define miRNA and disease gene signature demonstrated high performance to uncover new functional associations between miRNAs and diseases.  相似文献   

6.
The presented contribution concerns the study of several samples of Microcoryphia and of Zygentoma obtained in Israel; an up to date of the species of these insect Orders reported from Palestine is also presented. Genus Hyperlepisma (Lepismatidae: Ctenolepismatinae) is reported for the first time from the country and one new species H. palaestinensis n. sp., is described from the northern Negev. Another new species this one of the genus Lepidospora s. s. (Nicoletiidae: Coletiniinae), L. (L.) ayyalonica n. sp., is described from the Ayyalon Cave in Western Central Israel, from where several other terrestrial and aquatic endemic arthropods were already known.  相似文献   

7.
The new genusRhodothyrsus is proposed, based on the AmazonianSenefeldera macrophylla Ducke but also containing another newly described species,Rhodothyrsus hirsutus from northwestern Venezuela. The genus is a member of the tribe Hippomaneae of the Euphorbiaceae and apparently related toSenefeldera, but its closest relationships are still obscure, because the phylogeny of the tribe is poorly known and most of the significant characters ofRhodothyrsus are probably autapomorphies or symplesiomorphies. The restriction to tropical lowland rain forests is rare within the Hippomaneae, and several floral characters, pointing to a specialized pollination possibly by butterflies, are unique in the tribe.  相似文献   

8.
During the last five years our continued excavations in the known late Miocene mammal localities of Macedonia (Greece) provided several new specimens of the hominoid primate Ouranopithecus macedoniensis. This new material includes maxillary and mandibular remains and it is described and compared to the old material of Ouranopithecus in the present article. The material of Ouranopithecus from the three known localities “Ravin de la Pluie” (RPl), “Xirochori 1” (XIR) and “Nikiti 1” (NKT) includes a complete series of tooth rows representing all wearing stages. Thus, the study of the dental wear of Ouranopithecus upper and lower teeth is studied and compared to that of the recent hominoids Gorilla and Pan, as well as to Australopithecus afarensis. The latter species is well known by a series of tooth rows of different wearing stages. The canine’s attrition of Ouranopithecus has a more derived pattern than that of the recent hominoids (Gorilla and Pan) and less derived than A. afarensis. The p3 of Ouranopithecus has similar attrition to that of A. afarensis, the attrition of the molars in Ouranopithecus, A. afarensis and Pan follows a similar pattern, while in Gorilla it is different.  相似文献   

9.
Abstract

Hydrolytic stability of dithymidine phosphorothioates and dithioates bearing a glucuronic acid derivative protecting group on the phosphate linkage were studied in various biological media. We found that the enzymatic hydrolysis was accompanied by another reaction resulting in formation of the dithymidine phosphodiesters. We have proposed several possible mechanisms of hydrolysis.  相似文献   

10.
Recent bamboo collections from Brazil, and the study of specimens from several Brazilian herbaria revealed that the species described as Eremocaulon setosum, subtribe Guaduineae, in fact fits within the Arthrostylidiinae genus Aulonemia, based on floral and anatomical characters. Several characters found in this species, such as paniculate determinate synflorescences, solitary spikelets, an abaxial marginal green stripe on the foliage leaf blades, absence of stomata on the entire adaxial side of the leaf blade, and intercostal fibers in the mesophyll are typical features of the subtribe Arthrostylidiinae. The new combination Aulonemia setosa is here proposed, an epitype is designated, and a broader distributional range of this species is documented.  相似文献   

11.
IntroductionDropout is a highly prevalent and serious problem in assessing the effectiveness of weight loss studies and a major cause of treatment failure in the management of morbidly obese patients.ObjectivesTo determine which tests used for the psychometric evaluation of morbidly obese patients are more predictive of success/dropout in a weight loss program.MethodsSixty patients aged 18–65 attending the Outpatient Obesity Clinic between 2009 and 2011, were recruited for an intensive life style weight loss program. We compared the results obtained in Hamilton Depression scale, Hamilton Anxiety scale, Golombok Rust Inventory of Sexual Satisfaction, Eating Disorders Inventory-2, SF-36 Health Survey and Plutchik's Impulsivity questionnaire between patients who completed the intervention with those obtained in patients who did not complete it.ResultsThe rate of decline in the patients attending our program was 41.6% in the first year. Our results suggest that the Plutchik Impulsivity questionnaire, could be used as a predictive tool for success/attrition in intensive life style weight loss program.ConclusionsOur results suggest that the Plutchik Impulsivity questionnaire, could be used as a predictive tool for success/attrition in intensive life style weight loss program. The screening of patients prior to inclusion in these programs should help to optimize its efficacy and efficiency.  相似文献   

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PurposeInterventional radiology techniques cause radiation exposure both to patient and personnel. The radiation dose to the operator is usually measured with dosimeters located at specific points above or below the lead aprons. The aim of this study is to develop and validate two fast Monte Carlo (MC) codes for radiation transport in order to improve the assessment of individual doses in interventional radiology. The proposed methodology reduces the number of required dosemeters and provides immediate dose results.MethodsTwo fast MC simulation codes, PENELOPE/penEasyIR and MCGPU-IR, have been developed. Both codes have been validated by comparing fast MC calculations with the multipurpose PENELOPE MC code and with measurements during a realistic interventional procedure.ResultsThe new codes were tested with a computation time of about 120 s to estimate operator doses while a standard simulation needs several days to obtain similar uncertainties. When compared with the standard calculation in simple set-ups, MCGPU-IR tends to underestimate doses (up to 5%), while PENELOPE/penEasyIR overestimates them (up to 18%). When comparing both fast MC codes with experimental values in realistic set-ups, differences are within 25%. These differences are within accepted uncertainties in individual monitoring.ConclusionThe study highlights the fact that computational dosimetry based on the use of fast MC codes can provide good estimates of the personal dose equivalent and overcome some of the limitations of occupational monitoring in interventional radiology. Notably, MCGPU-IR calculates both organ doses and effective dose, providing a better estimate of radiation risk.  相似文献   

14.
AimNowadays, no Quality Indicators (QI) have been proposed for Hyperthermia treatments. Starting from radiotherapy experience, the aim of this work is to adapt radiotherapy indicators to Hyperthermia and to propose a new specific set of QI in Hyperthermia field.Material and methodsAt first, radiotherapy quality indicators published in literature have been adapted to hyperthermia setting. Moreover, new specific indicators for the treatment of hyperthermia have been defined. To obtain the standard reference values of quality indicators, a questionnaire was sent to 7 Italian hyperthermia Institutes with a list of questions on physical and clinical hyperthermia treatment in order to highlight the different therapeutic approaches.ResultsThree structure, five process and two outcome QI were selected. It has been possible to adapt seven indicators from radiotherapy, while three indicators have been defined as new specific indicators for hyperthermia. Average values used as standard reference values have been obtained and proposed.ConclusionThe survey performed on 7 Italian centres allowed to derive the standard reference value for each indicator. The proposed indicators are available to be investigated and applied by a larger number of Institutes in which hyperthermia treatment is performed in order to monitor the operational procedures and to confirm or modify the reference standard value derived for each indicator.  相似文献   

15.
Abstract

Amyloid β (Aβ) peptides fibril formation and deposition is considered to be the principal pathological hallmark of Alzheimer's disease (AD). However, it remains obscure why AD is precluded by rat/mouse despite the high sequence identity (97%) of rat/mouse Aβ to its human homologue. Based on the recently proposed redox chemistry-based pathogenic model of neurodegenerative diseases, we hypothesize that the lack of key residues of rat/mouse Aβ compared with the human counterpart may account for why rat/mouse is free of AD. At the same time, we propose a new possible redox chemistry-based pathogenic model of AD based on the experimental observations of certain residues in triggering Aβ aggregation. Moreover, it is also interesting to note that non-mammalian Xenopus Aβ contains all the redox chemistry-related key residues and whether it implies that Xenopus Aβ possesses high amyloidogenic potency remains to be determined by further experimental study.  相似文献   

16.
PurposeMicron-scale computed tomography (micro-CT) imaging is a ubiquitous, cost-effective, and non-invasive three-dimensional imaging modality. We review recent developments and applications of micro-CT for preclinical research.MethodsBased on a comprehensive review of recent micro-CT literature, we summarize features of state-of-the-art hardware and ongoing challenges and promising research directions in the field.ResultsRepresentative features of commercially available micro-CT scanners and some new applications for both in vivo and ex vivo imaging are described. New advancements include spectral scanning using dual-energy micro-CT based on energy-integrating detectors or a new generation of photon-counting x-ray detectors (PCDs). Beyond two-material discrimination, PCDs enable quantitative differentiation of intrinsic tissues from one or more extrinsic contrast agents. When these extrinsic contrast agents are incorporated into a nanoparticle platform (e.g. liposomes), novel micro-CT imaging applications are possible such as combined therapy and diagnostic imaging in the field of cancer theranostics. Another major area of research in micro-CT is in x-ray phase contrast (XPC) imaging. XPC imaging opens CT to many new imaging applications because phase changes are more sensitive to density variations in soft tissues than standard absorption imaging. We further review the impact of deep learning on micro-CT. We feature several recent works which have successfully applied deep learning to micro-CT data, and we outline several challenges specific to micro-CT.ConclusionsAll of these advancements establish micro-CT imaging at the forefront of preclinical research, able to provide anatomical, functional, and even molecular information while serving as a testbench for translational research.  相似文献   

17.
New directions and new questions raised in the study of health in the past justify this reanalysis of the pattern of dental attrition in the Medieval Danish population of Tirup. Dental attrition was scored on all permanent molars from the Tirup skeletal sample. Scores were analyzed by means of logistic regression of the probability of having entered a given stage of wear for a given tooth in a way that is very similar to transition analysis. The primary determinant of dental attrition was age at death. In addition to age, the effects of sex, side, and dating were analyzed. In order to assess the homogeneity of the process of wearing teeth down, a third-order polynomial in age-at-death was also fitted to the transition probabilities. It was found that age is the single most important determinant of dental attrition, and that sex or side did not differentiate the rate of attrition. In several transitions, there was evidence of heterogeneity, indicating both random and systematic interpersonal differences in the rate of attrition and an association between the rate of attrition and age-at-death. It was found that attrition proceeded more quickly after AD 1300 than prior to that date. It is suggested that this was due to a possible general deterioration of living conditions in Northern Europe and an increased reliance on grain for food during the first half of the 14th century. The temporal effect on attrition rate accounts for some but not all the observed heterogeneity wear.  相似文献   

18.
The incidences of 31 minor variants of the dental crown were scored from dental casts of samples taken from six European populations. Although several variants showed significant sex bias in one or other sample, only one (pits instead of furrow on premolar2) consistently favoured one sex. Associations between the variants were sought. Although few consistent associations were demonstrated, there was a possible tendency for extra cusps to occur together throughout the dentition. Distance statistics calculated between the samples were compatible with the expected genetical relationships of the samples, but only modern samples could be used since variants were destroyed by attrition in archeological samples. Before such distances can be considered reliable, it is necessary to know:
  • i the extent to which environmental factors such as diet influence variant expression.
  • ii whether or not variant bearing teeth are selectively destroyed by caries, which in civilised populations render a high proportion of most dentitions unscoreable.
  相似文献   

19.
BackgroundThe Nigerian Antiretroviral therapy (ART) program started in 2004 and now ranks among the largest in Africa. However, nationally representative data on outcomes have not been reported.MethodsWe evaluated retrospective cohort data from a nationally representative sample of adults aged ≥15 years who initiated ART during 2004 to 2012. Data were abstracted from 3,496 patient records at 35 sites selected using probability-proportional-to-size (PPS) sampling. Analyses were weighted and controlled for the complex survey design. The main outcome measures were mortality, loss to follow-up (LTFU), and retention (the proportion alive and on ART). Potential predictors of attrition were assessed using competing risk regression models.ResultsAt ART initiation, 66.4 percent (%) were females, median age was 33 years, median weight 56 kg, median CD4 count 161 cells/mm3, and 47.1% had stage III/IV disease. The percentage of patients retained at 12, 24, 36 and 48 months was 81.2%, 74.4%, 67.2%, and 61.7%, respectively. Over 10,088 person-years of ART, mortality, LTFU, and overall attrition (mortality, LTFU, and treatment stop) rates were 1.1 (95% confidence interval (CI): 0.7–1.8), 12.3 (95%CI: 8.9–17.0), and 13.9 (95% CI: 10.4–18.5) per 100 person-years (py) respectively. Highest attrition rates of 55.4/100py were witnessed in the first 3 months on ART. Predictors of LTFU included: lower-than-secondary level education (reference: Tertiary), care in North-East and South-South regions (reference: North-Central), presence of moderate/severe anemia, symptomatic functional status, and baseline weight <45kg. Predictor of mortality was WHO stage higher than stage I. Male sex, severe anemia, and care in a small clinic were associated with both mortality and LTFU.ConclusionModerate/Advanced HIV disease was predictive of attrition; earlier ART initiation could improve program outcomes. Retention interventions targeting men and those with lower levels of education are needed. Further research to understand geographic and clinic size variations with outcome is warranted.  相似文献   

20.
目的:探究将统计学习方法应用于心理测验所得的大量数据进行学习分析的可行性,并基于探究结果对飞行职业的人格特征进行进一步探索,为飞行人员的选拔及评估提供新的思路。方法:从某航空公司随机抽取1020名男性被试,其中飞行人员510名,非飞行人员510名,采用卡特尔16项人格测试对其进行测验,施测后对得到的16项因子分采用支持向量机就随机划分的训练组和测试组进行学习,分析学习结果。结果:挑选出4项因子作为分类的特征因子,基于线性支持向量机构建的分类器在交叉验证下的平均正确率为64%。结论:采用SVM构建的分类器具有一定的可靠性和有效性。  相似文献   

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