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71.
An immunogold assay (IGA) was developed to detect IgG and IgE antibodies to Aspergillus fumigatus. Sixteen sera from patients with allergic bronchopulmonary aspergillosis (ABPA), aspergilloma, and normal controls were studied. All sera were also evaluated for antibodies against A. fumigatus by biotin-avidin linked enzyme immunosorbent assay (BALISA) and by agar gel double diffusion method. A. fumigatus specific IgG and IgE antibodies could be detected by IGA in all the patients' sera but not in the sera of normal controls. Both IgG and IgE antibodies to A. fumigatus could be demonstrated in all the sera by BALISA and normal controls showed only low levels of these antibodies. There was a positive correlation between the degree of reactivity detected by IGA, the BALISA titer and the precipitins by agar gel diffusion. It can be concluded that IGA is a reliable, sensitive and simple method capable of detecting both IgG and IgE antibodies against A. fumigatus in patient serum.  相似文献   
72.

Background

Exposure to mass media may impact the use of tobacco, a major source of illness and death in India. The objective is to test the association of self-reported tobacco smoking and chewing with frequency of use of four types of mass media: newspapers, radio, television, and movies.

Methodology/Principal Findings

We analyzed data from a sex-stratified nationally-representative cross-sectional survey of 123,768 women and 74,068 men in India. All models controlled for wealth, education, caste, occupation, urbanicity, religion, marital status, and age. In fully-adjusted models, monthly cinema attendance is associated with increased smoking among women (relative risk [RR]: 1·55; 95% confidence interval [CI]: 1·04–2·31) and men (RR: 1·17; 95% CI: 1·12–1·23) and increased tobacco chewing among men (RR: 1·15; 95% CI: 1·11–1·20). Daily television and radio use is associated with higher likelihood of tobacco chewing among men and women, while daily newspaper use is related to lower likelihood of tobacco chewing among women.

Conclusion/Significance

In India, exposure to visual mass media may contribute to increased tobacco consumption in men and women, while newspaper use may suppress the use of tobacco chewing in women. Future studies should investigate the role that different types of media content and media play in influencing other health behaviors.  相似文献   
73.
Clinical trials increasingly employ medical imaging data in conjunction with supervised classifiers, where the latter require large amounts of training data to accurately model the system. Yet, a classifier selected at the start of the trial based on smaller and more accessible datasets may yield inaccurate and unstable classification performance. In this paper, we aim to address two common concerns in classifier selection for clinical trials: (1) predicting expected classifier performance for large datasets based on error rates calculated from smaller datasets and (2) the selection of appropriate classifiers based on expected performance for larger datasets. We present a framework for comparative evaluation of classifiers using only limited amounts of training data by using random repeated sampling (RRS) in conjunction with a cross-validation sampling strategy. Extrapolated error rates are subsequently validated via comparison with leave-one-out cross-validation performed on a larger dataset. The ability to predict error rates as dataset size increases is demonstrated on both synthetic data as well as three different computational imaging tasks: detecting cancerous image regions in prostate histopathology, differentiating high and low grade cancer in breast histopathology, and detecting cancerous metavoxels in prostate magnetic resonance spectroscopy. For each task, the relationships between 3 distinct classifiers (k-nearest neighbor, naive Bayes, Support Vector Machine) are explored. Further quantitative evaluation in terms of interquartile range (IQR) suggests that our approach consistently yields error rates with lower variability (mean IQRs of 0.0070, 0.0127, and 0.0140) than a traditional RRS approach (mean IQRs of 0.0297, 0.0779, and 0.305) that does not employ cross-validation sampling for all three datasets.  相似文献   
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Farmed fish could substitute for marine capture fish as a source of fatty acids such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) beneficial for human health; however, they require these compounds in their diets. In the present study on a model fish species, we modified the EPA/DHA biosynthesis pathway by overexpression of masu salmon Δ5-desaturase-like gene in zebrafish to increase its ability to synthesize EPA and DHA. Expression of this gene in transgenic fish fed a commercial diet and Artemia helped to improve their EPA content by 1.21-fold and DHA by 1.24-fold. In similar fish that were fed only Artemia the increments were 1.14-fold for EPA and 1.13-fold for DHA, compared with nontransgenic fish. In contrast, eicosatetraenoic acid content decreased, as it is a substrate of Δ5-desaturase, while the total lipid remained constant. The results demonstrated that masu salmon Δ5-desaturase is functional in zebrafish and can modify its fatty acid metabolic pathway. The technique could be applied to farmed fish to generate a nutritionally richer product for human consumption.  相似文献   
76.
Six members of the mammalian transient receptor potential (TRP) ion channels respond to varied temperature thresholds. The natural compounds capsaicin and menthol activate noxious heat-sensitive TRPV1 and cold-sensitive TRPM8, respectively. The burning and cooling perception of capsaicin and menthol demonstrate that these ion channels mediate thermosensation. We show that, in addition to noxious cold, pungent natural compounds present in cinnamon oil, wintergreen oil, clove oil, mustard oil, and ginger all activate TRPA1 (ANKTM1). Bradykinin, an inflammatory peptide acting through its G protein-coupled receptor, also activates TRPA1. We further show that phospholipase C is an important signaling component for TRPA1 activation. Cinnamaldehyde, the most specific TRPA1 activator, excites a subset of sensory neurons highly enriched in cold-sensitive neurons and elicits nociceptive behavior in mice. Collectively, these data demonstrate that TRPA1 activation elicits a painful sensation and provide a potential molecular model for why noxious cold can paradoxically be perceived as burning pain.  相似文献   
77.
Endonuclease VIII-like 3 (Neil3) is one of the five DNA glycosylases found in mammals that recognize and remove oxidized bases, and initiate the base excision repair (BER) pathway. Previous attempts to express and purify the mouse and human orthologs of Neil3 in their active form have not been successful. Here we report the construction of bicistronic expression vectors for expressing in Escherichia coli the full-length mouse Neil3 (MmuNeil3), its glycosylase domain (MmuNeil3Δ324), as well as the glycosylase domain of human Neil3 (NEIL3Δ324). The purified Neil3 proteins are all active, and NEIL3Δ324 exhibits similar glycosylase/lyase activity as MmuNeil3Δ324 on both single-stranded and double-stranded substrates containing thymine glycol (Tg), spiroiminodihydantoin (Sp) or an abasic site (AP). We show that N-terminal initiator methionine processing is critical for the activity of both mouse and human Neil3 proteins. Co-expressing an E. coli methionine aminopeptidase (EcoMap) Y168A variant with MmuNeil3, MmuNeil3Δ324 and NEIL3Δ324 improves the N-terminal methionine processing and increases the percentage of active Neil3 proteins in the preparation. The purified Neil3 proteins are suitable for biochemical, structural and functional studies.  相似文献   
78.

Background

Poor self-rated health (SRH) is socially patterned with health communication inequalities, arguably, serving as one mechanisms. This study investigated the effects of health information seeking on SRH, and its mediation effects on disparities in SRH.

Methods

We conducted probability-based telephone surveys administered over telephone in 2009, 2010/11 and 2012 to monitor health information use among 4553 Chinese adults in Hong Kong. Frequency of information seeking from television, radio, newspapers/magazines and Internet was dichotomised as <1 time/month and ≥1 time/month. Adjusted odds ratios (aOR) for poor SRH were calculated for health information seeking from different sources and socioeconomic status (education and income). Mediation effects of health information seeking on the association between SES and poor SRH was estimated.

Results

Poor SRH was associated with lower socioeconomic status (P for trend <0.001), and less than monthly health information seeking from newspapers/magazines (aOR = 1.23, 95% CI 1.07–1.42) and Internet (aOR = 1.13, 95% CI 0.98–1.31). Increasing combined frequency of health information seeking from newspapers/magazines and Internet was linearly associated with better SRH (P for trend <0.01). Health information seeking from these two sources contributed 9.2% and 7.9% of the total mediation effects of education and household income on poor SRH, respectively.

Conclusions

Poor SRH was associated with lower socioeconomic status, and infrequent health information seeking from newspapers/magazines and Internet among Hong Kong Chinese. Disparities in SRH may be partially mediated by health information seeking from newspapers/magazines and Internet.  相似文献   
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