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11.
Exercising or working in a hot, humid environment can results in the onset of heat-related illness when an individual''s temperature is not carefully monitored. The purpose of the present study was to compare three techniques (data loggers, thermal imaging, and wired electrodes) for the measurement of peripheral (bicep) and central (abdominal) skin temperature. Young men and women (N = 30) were recruited to complete the present study. The three skin temperature measurements were made at 0 and every 10-min during 40-min (60% VO2max) of cycling in a hot (39±2°C), humid (45±5% RH) environment. Data was statistically analyzed using the Bland-Altman method and correlation analysis. For abdominal skin temperature, the Bland-Altman limits of agreement indicated that data loggers (1.5) were a better index of wired than was thermal imaging (3.5), For the bicep skin temperature the limits of agreement was similar between data loggers (1.9) and thermal (1.9), suggesting the both were suitable measurements. We also found that when skin temperature exceeded 35°C, we observed progressively better prediction between data loggers, thermal imaging, and wired skin sensors. This report describes the potential for the use of data loggers and thermal imaging to be used as alternative measures of skin temperature in exercising, human subjects.  相似文献   
12.

Background

Angiogenesis, the formation of new blood vessels, has become an important target in cancer therapy. Angiogenesis plays an important role in tumor growth and metastasis. Koetjapic acid (KA) is a seco-A-ring oleanene triterpene isolated from S. koetjape. The solvent extract of this plant species was shown previously to have strong antiangiogenic activity; however the active ingredient(s) that conferred the biological activity and the mode of action was not established. Given the high concentration of KA in S. koetjape, an attempt has been made in this study to investigate the antiangiogenic properties of KA.

Results

Treatment with 10-50 μg/ml KA resulted in dose dependent inhibition of new blood vessels growth in ex vivo rat aortic ring assay. KA was found to be non-cytotoxic against HUVECs with IC50 40.97 ± 0.37 μg/ml. KA inhibited major angiogenesis process steps, endothelial cell migration and differentiation as well as VEGF expression.

Conclusions

The non-cytotoxic compound, KA, may be a potent antiangiogenic agent; its activity may be attributed to inhibition of endothelial cells migration and differentiation as well VEGF suppression.  相似文献   
13.
Prostate cancer is the most commonly diagnosed cancer among men in the developed countries. (1) One in six males in the U.S. (2) and one in nine males in the U.K. (3) will develop the disease at some point during their lifetime. Despite advances in prostate cancer screening, more than a quarter of a million men die from the disease every year (1) due primarily to treatment-resistance and metastasis. Colloidal nanotechnologies can provide tremendous enhancements to existing targeting/treatment strategies for prostate cancer to which malignant cells are less sensitive. Here, we show that antiandrogen gold nanoparticles-multivalent analogues of antiandrogens currently used in clinical therapy for prostate cancer-selectively engage two distinct receptors, androgen receptor (AR), a target for the treatment of prostate cancer, as well as a novel G-protein coupled receptor, GPRC6A, that is also upregulated in prostate cancer. These nanoparticles selectively accumulated in hormone-insensitive and chemotherapy-resistant prostate cancer cells, bound androgen receptor with multivalent affinity, and exhibited greatly enhanced drug potency versus monovalent antiandrogens currently in clinical use. Further, antiandrogen gold nanoparticles selectively stimulated GPRC6A with multivalent affinity, demonstrating that the delivery of nanoscale antiandrogens can also be facilitated by the transmembrane receptor in order to realize increasingly selective, increasingly potent therapy for treatment-resistant prostate cancers.  相似文献   
14.
Polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) were analysed from sediment samples collected in 2012 from rivers, surface runoff canals and estuaries in three highly urbanised catchments in durban, KwaZulu-Natal, South Africa. PAHs were ubiquitous, at concentrations between 36–6 800 ng g?1 dry mass (dm). Congener ratio diagnosis suggests the PAHs were derived predominantly from pyrogenic sources. Four OCPs and/or their metabolites were detected at varying frequencies and concentrations. Of these, dichlorodiphenyltrichloroethane (ddT) and metabolites were most frequently detected and were at a high concentration in sediment in some systems. Toxaphene was detected at a high concentration at some sites. The total PCB concentration varied widely, from below the method detection limit to 110 ng g?1 (dm). Based on the comparison of chemical concentrations to international sediment quality guidelines, PAH, OCP and PCB concentrations in most sediment samples posed a low risk to sediment-dwelling organisms. However, in some instances the risk was moderate or high. It is recommended that these compounds be monitored more frequently and comprehensively in aquatic ecosystems to better understand the ecological and human health implications.  相似文献   
15.
The basal rate of metabolism (BMR) in 533 species of birds, when examined with ANCOVA, principally correlates with body mass, most of the residual variation correlating with food habits, climate, habitat, a volant or flightless condition, use or not of torpor, and a highland or lowland distribution. Avian BMR also correlates with migratory habits, if climate and a montane distribution is excluded from the analysis, and with an occurrence on small islands if a flightless condition and migration are excluded. Residual variation correlates with membership in avian orders and families principally because these groups are behaviorally and ecologically distinctive. However, the distinction between passerines and other birds remains a significant correlate of avian BMR, even after six ecological factors are included, with other birds having BMRs that averaged 74% of the passerine mean. This combination of factors accounts for 97.7% of the variation in avian BMR. Yet, migratory species that belong to Anseriformes, Charadriiformes, Pelecaniformes, and Procellariiformes and breed in temperate or polar environments have mass-independent basal rates equal to those found in passerines. In contrast, penguins belong to an order of polar, aquatic birds that have basal rates lower than passerines because their flightless condition depresses basal rate. Passerines dominate temperate, terrestrial environments and the four orders of aquatic birds dominate temperate and polar aquatic environments because their high BMRs facilitate reproduction and migration. The low BMRs of tropical passerines may reflect a sedentary lifestyle as much as a life in a tropical climate. Birds have BMRs that are 30-40% greater than mammals because of the commitment of birds to an expensive and expansive form of flight.  相似文献   
16.
Integrated conservation and development projects (ICDPs) have had limited success in addressing the often conflicting objectives of conservation and development. We developed a model with local participants to explore the trade-offs between conservation and development in southeastern Cameroon, where illegal hunting is regarded as the greatest challenge to conservation. We simulated the effects of different ICDP strategies by varying the degree of focus on antipoaching activities, anticorruption measures and direct development investments, and by varying the overall budget for such activities. Our outcome variables were numbers of selected wildlife species and household incomes. The model outcomes from the different scenarios were used to stimulate debate among stakeholders. Contributing to poverty alleviation while maintaining current animal population sizes will be extremely difficult and will require long-term external financial support. Devoting greater attention to improving local environmental governance emerged as the highest priority for this investment. We used the model outputs to inform some of the major policy makers in the region. Participatory modeling is a valuable means of capturing the complexities of achieving conservation at landscape scales and of stimulating innovative solutions to entrenched problems.  相似文献   
17.
An approach to assessing the environmental outcomes and changes in peoples’ livelihoods resulting from landscape-scale conservation interventions was developed for three locations in Africa. Simple sets of performance indicators were developed through participatory processes that included a variety of stakeholders. The selection of indicators was designed to reflect wider landscape processes, conservation objectives and as local peoples’ preferred scenarios. This framework, combined with the use of social learning techniques, helped stakeholders develop greater understandings of landscape system dynamics and the linkages between livelihood and conservation objectives. Large scale conservation and development interventions should use these approaches to explore linkages and improve shared understanding of tradeoffs and synergies between livelihood and conservation initiatives. Such approaches provide the basis for negotiating and measuring the outcomes of conservation initiatives and for adapting these to changing perspectives and circumstances.  相似文献   
18.
Juyal G  Prasad P  Senapati S  Midha V  Sood A  Amre D  Juyal RC  BK T 《PloS one》2011,6(1):e16565
Genome-Wide Association studies (GWAS) of both Crohn's Disease (CD) and Ulcerative Colitis (UC) have unearthed over 40 risk conferring variants. Recently, a meta-analysis on UC revealed several loci, most of which were either previously associated with UC or CD susceptibility in populations of European origin. In this study, we attempted to replicate these findings in an ethnically distinct north Indian UC cohort. 648 UC cases and 850 controls were genotyped using Infinium Human 660W-quad. Out of 59 meta-analysis index SNPs, six were not in the SNP array used in the study. Of the remaining 53 SNPs, four were found monomorphic. Association (p<0.05) at 25 SNPs was observed, of which 15 were CD specific. Only five SNPs namely rs2395185 (HLA-DRA), rs3024505 (IL10), rs6426833 (RNF186), rs3763313 (BTNL2) and rs2066843 (NOD2) retained significance after Bonferroni correction. These results (i) reveal limited replication of Caucasian based meta-analysis results; (ii) reiterate overlapping molecular mechanism(s) in UC and CD; (iii) indicate differences in genetic architecture between populations; and (iv) suggest that resources such as HapMap need to be extended to cover diverse ethnic populations. They also suggest a systematic GWAS in this terrain may be insightful for identifying population specific IBD risk conferring loci and thus enable cross-ethnicity fine mapping of disease loci.  相似文献   
19.
Most studies of the association between family structure and risky sexual behaviour among adolescents and young adults have employed a risk perspective which assumes that, compared with other types, two-parent families are protective. Drawing from a positive-oriented approach in this study, it is hypothesized that within each family type some influential factors may mitigate such anticipated deleterious effects of non-intact families and decrease sexual risk-taking. The paper examines specifically the effects of risk and protective factors with an emphasis on family processes associated with resilience, using data from a pooled sample of 1025 females and males aged 12-24 years from Bandjoun (West Cameroon). Findings show that the quality of parent/guardian-youth relationships significantly decreases the odds of risky sexual behaviour by 36%, 65% and 50% in neither-, one- and two-parent families, respectively. For two-parent families only, parental control acts as a significant protective factor; it decreased by 41% the odds of risky sexual behaviour. Programmatically, protective family factors such as parent/guardian-youth interactions need to be promoted to improve the efficiency of reproductive health and HIV interventions in sub-Saharan Africa.  相似文献   
20.
Natural selection can favor songbirds that desert nests containingeggs of the parasitic brown-headed cowbird (Molothrus ater).However, the high variability in desertion of parasitized nestswithin species is perplexing in light of the typically highcosts of parasitism. Because nest desertion can also be a responseto partial clutch predation, we first asked if Bell's vireos(Vireo bellii) deserted nests in response to the presence ofcowbird eggs (antiparasite response hypothesis) or to egg removalby predators and female cowbirds (egg predation hypothesis).Second, we asked whether variation in nest desertion was dueto intrinsic differences among individuals or to variation innest contents. We monitored a large number of nests (n = 494)and performed a clutch manipulation experiment to test thesehypotheses. The number of vireo eggs that remained in a nestwas a strong predictor of desertion both within and among pairs.Neither the presence of a single cowbird egg, which leads tonest failure for this host, nor the number of cowbird eggs receivedin a vireo nest influenced nest desertion. Furthermore, vireosdid not desert experimental nests when we immediately exchangedcowbird eggs for vireo eggs but deserted if we removed vireoeggs and replaced them with cowbird eggs the following morning.Desertion of parasitized nests by Bell's vireos can be almostentirely explained as a response to partial or complete clutchloss and does not appear to have been altered by selection frombrood parasitism.  相似文献   
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