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101.
Ticks are ectoparasites of wild and domestic animals and humans, and are considered to be the most important arthropod vector of pathogens in North America. Development of vaccines directed against tick proteins may effect reduction of tick infestations and transmission of tick-borne pathogens. The limiting step for the development of tick vaccines has been the identification of tick protective antigens. Reverse vaccinology approaches aimed at reducing animal experimentation while allowing for the rapid screening of pools of potential tick vaccine candidates would greatly facilitate progress towards the development of tick vaccines. Herein, we describe the screening of Ixodes scapularis cDNAs for identification of tick protective antigens using RNA interference (RNAi). The results of the RNAi screening were similar to those obtained previously using expression library immunization and demonstrated that RNAi could serve as a more rapid and cost-effective tool for vaccine antigen discovery in ticks and in other nonmodel organisms.  相似文献   
102.
Stress, coping, and hepatitis B antibody status   总被引:4,自引:0,他引:4  
OBJECTIVE: The present study investigated the association between exposure to stressful life events, coping style, and antibody status after hepatitis B vaccination. METHODS: Two hundred sixty medical school undergraduates, who had received the three-dose hepatitis B vaccine before recruitment to this study, completed questionnaires measuring exposure to stressful life events during the past year, customary coping strategies, and health behaviors. Antibodies against hepatitis B surface antigen were determined; levels <100 mIU/ml were deemed inadequate. RESULTS: Two participant cohorts were identified: those vaccinated within the last year and those vaccinated earlier. In the early vaccination cohort, participants with greater-than-average stress exposures had a more than two-fold increased risk of having an inadequate antibody titer. Coping by accepting the reality of stressful situations proved protective, whereas coping by substance use increased the risk of having an inadequate antibody count in this cohort. These associations remained significant after adjustment for possible mediators. Furthermore, the effects of stress and coping were largely independent of one another. Neither stress nor coping was significantly associated with antibody status in the recently vaccinated cohort. CONCLUSIONS: The present study confirms that the immune system is sensitive to variations in psychological factors. Stressful life events and coping strategy seem to have a continuing impact on hepatitis B antibody status.  相似文献   
103.
The ultrastructural arrangement of Kell (K1) and Cellano (K2) antigens on red cells was studied using ferritin-conjugated rabbit antihuman IgG to stain ghosts derived from antibody-sensitized intact red cells. Estimates of the number of sites under equilibrium binding were obtained by counting both ferritin grains and ferritin clusters on electron micrographs. Values for Kell sites on heterozygous red cells ranged from 2300 to 5900 and for Cellano sites from 2000 to 5000 with no discernible dosage effects. Both the Kell and Cellano antigens were clustered, which was due to conjugate staining of the ghost membranes and does not reflect the topological arrangement of these antigens on the native membrane. The ferritin grain patterns found with the Kell and Cellano antigens was similar to those observed with the Rh antigens except for the markedly reduced antigen site density.  相似文献   
104.
The aim of this study is to investigate the association between three polymorphisms of the interleukin-1 (IL-1) gene complex and schizophrenia. We genotyped 228 outpatients with schizophrenia (DSM-IV criteria) and 419 unrelated healthy controls. The following polymorphisms were analyzed: IL-1alpha -889 C/T, IL-1beta +3953 C/T, and IL-1RA (86 bp)n. No significant differences in genotype or in allelic distribution of the Il-1alpha, IL-1beta, and IL-1RA polymorphisms were found. Estimated haplotype frequencies were similar in both groups. Our data do not suggest that genetically determined changes in the IL-1 gene complex confer increased susceptibility for schizophrenia.  相似文献   
105.
BACKGROUND: There are wide global variations in the prevalence of asthma and wheezing. OBJECTIVES: We examined the associations of place of birth with doctor-diagnosed asthma, wheezing in the past 12 months, and other allergic conditions in Mexican American children. METHODS: The study used data on 4121 Mexican American children age 2 months to 16 years who participated in the Third National Health and Nutrition Examination Survey. RESULTS: The risk of asthma was associated with being born in the United States after adjusting for sex, age, history of ear infection, and having a regular place for health care (odds ratio, 2.19; 95% CI, 1.09-4.40). Among children with no previous history of ear infection, US-born children were more likely to report wheezing in the past 12 months than their peers born in Mexico after controlling for confounding variables (odds ratio, 2.05; 95% CI, 1.09-3.87). Mexican American children born in the United States were more likely to have positive skin reaction to cat, house mite, Alternaria alternata , peanut, Bermuda grass, and short ragweed but were less likely to have a positive skin test to German cockroaches after adjusting for sex, age, ear infection, having a regular place for health care, and area of residence. CONCLUSION: Our study indicated significant associations of place of birth with respiratory symptoms and allergic conditions in Mexican American children. These findings highlight the need for further studies to examine environmental factors that change by migration and explain the observed differential in the risk of asthma or wheezing.  相似文献   
106.
Quality of Life Research - This study examined the clinical utility of post-traumatic stress disorder (PTSD), low resilience, poor sleep, and lifetime blast exposure as risk factors for predicting...  相似文献   
107.
Maternal and Child Health Journal - The Maternal and Child Health (MCH) Pipeline Training Program, promotes development of a diverse health workforce by training undergraduate students from...  相似文献   
108.
Advances in Health Sciences Education - Critical reflection supports enactment of the social roles of care, like collaboration and advocacy. We require evidence that links critical teaching...  相似文献   
109.
While athletes’ nutrient intakes have been widely reported, few studies have assessed the diet quality of athletes. This is the first study to evaluate the diet quality of athletes using the purpose-built Athlete Diet Index (ADI). A convenience sample of 165 elite athletes from Australian sporting institutions completed the ADI online, with subsequent automated results provided to their respective accredited sports dietitians (ASDs). At the completion of athlete participation, ASDs (n = 12) responded to a range of survey items using a Likert scale (i.e., 1 = strongly agree to 5 = strongly disagree) to determine the suitability of the ADI in practice. Differences in ADI scores for demographics and sport-specific variables were investigated using independent t-tests, analysis of variance (ANOVA) and Bonferroni multiple comparisons. Spearman’s rank correlation was used to assess the association between total scores and demographics. The mean total ADI score was 91.4 ± 12.2 (range 53–117, out of a possible 125). While there was no difference in total scores based on demographics or sport-specific variables; team sport athletes scored higher than individual sport athletes (92.7 vs. 88.5, p < 0.05). Athletes training fewer hours (i.e., 0–11 h/week) scored higher on Dietary Habits sub-scores compared with athletes training more hours (≥12 h/week; p < 0.05), suggesting that athletes who train longer may be at risk of a compromised dietary pattern or less than optimal nutrition practices that support training. Most (75%) ASDs surveyed strongly agreed with the perceived utility of the ADI for screening athletes and identifying areas for nutrition support, confirming its suitability for use in practice.  相似文献   
110.
Relative to other racial/ethnic groups in the United States, Hispanic American (HA) youth have higher rates of overweight and obesity. Previous work suggests that low perceived social status (SS) promotes excess caloric intake and, thereby, development of obesity. Psychological resilience may play a role in reducing adverse eating behaviors and risk for obesity. The objective of this study was to investigate whether resilience (as measured by the Connor Davidson Resilience Scale) interacts with experimentally manipulated SS to affect dietary intake among HA adolescents (n = 132). Using a rigged game of Monopoly (Hasbro, Inc.), participants were randomized to a high or low SS condition. Following the Monopoly game, participants consumed an ad libitum lunch and their dietary intake was assessed. There was a significant interaction between resilience and experimentally manipulated SS for total energy intake (p = 0.006), percent energy needs consumed (p = 0.005), and sugar intake (p = 0.004). For the high SS condition, for each increase in resilience score, total energy intake decreased by 7.165 ± 2.866 kcal (p = 0.014) and percent energy needs consumed decreased by 0.394 ± 0.153 (p = 0.011). In the low SS condition, sugar intake increased by 0.621 ± 0.240 g for each increase in resilience score (p = 0.011). After correction for multiple comparisons, the aforementioned interactions, but not simple slopes, were statistically significant.  相似文献   
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