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Younger Females (younger + female)
Selected AbstractsRisk of pancreatic adenocarcinomaCANCER, Issue 2 2005Disparity between African Americans, other race/ethnic groups Abstract BACKGROUND African Americans have a higher incidence of pancreatic adenocarcinoma compared with non-Hispanic whites. Whether other clinical differences exist between these two groups is not well known. METHODS The authors conducted a population-based retrospective analysis of all patients with pancreatic adenocarcinoma in both a regional and a statewide database between 1988 and 1998. Their goal was to evaluate differences in incidence rates, clinical presentation, including age at diagnosis, gender, and tumor characteristics, and treatment among race/ethnic groups. RESULTS African Americans had a higher age-adjusted incidence rate of pancreatic adenocarcinoma (8.78) compared with non-Hispanic whites (5.89), Hispanics (5.09), Asians (4.75), and all race/ethnicities combined (5.82). African Americans also presented at a later stage of disease and received less surgery than all other race/ethnicities, despite equal availability of medical insurance. The analyses also revealed gender differences. In general, males maintained a higher incidence rate of pancreatic adenocarcinoma than females across all race/ethnicities. In all race/ethnic groups, females were diagnosed at an older age and an earlier stage of disease than males. The proportional hazard mortality ratio for females age < 60 was significantly less than that for males in the same age group (P < 0.02), even after accounting for stage and treatment. CONCLUSIONS African Americans in California had a higher incidence rate of pancreatic adenocarcinoma, had a slightly higher risk of presenting with advanced-stage diseas and with nonresectable tumors (i.e., tumors located in the body or tail of the pancreas), and underwent less surgical treatment than all other race/ethnicities. Younger females in all race/ethnic groups had a survival advantage over males of the same age. Cancer 2005. © 2004 American Cancer Society. [source] Age-dependent reproductive costs and the role of breeding skills in the Collared flycatcherACTA ZOOLOGICA, Issue 2 2007Joanna Sendecka Abstract This study addressed whether there are any age-related differences in reproductive costs. Of especial interest was whether young individuals increased their reproductive effort, and thereby their reproductive cost, as much as older birds when brood size was enlarged. To address these questions, a brood-size manipulation experiment with reciprocal cross-fostering of nestlings of young and middle-aged female Collared flycatchers, Ficedula albicollis, was performed on the Swedish island of Gotland. Nestlings' body mass, tarsus length and survival were recorded to estimate the parental ability and parental effort of the experimental female birds. Female survival and clutch size were recorded in the following years to estimate reproductive costs. We found that middle-aged female flycatchers coped better with enlarged broods than younger females or invested more in reproduction. In the following year, young female birds that had raised enlarged broods laid smaller clutches than the females from all the other experimental groups. This result shows that the young female birds pay higher reproductive costs than the middle-aged females. Both young and middle-aged female flycatchers seemed to increase their reproductive effort when brood size was increased. However, such an increase resulted in higher reproductive costs for the young females. The difference in reproductive costs between birds of different ages is most likely a result of insufficient breeding skills of the young individuals. [source] Physical apertures as constraints on egg size and shape in the Common Musk Turtle, Sternotherus odoratusFUNCTIONAL ECOLOGY, Issue 1 2001P. J. Clark Summary 1,Egg size in turtles often increases with female size, contrary to expectations of optimality. Functional constraints on egg width imposed by the pelvic aperture or the gap between the carapace and plastron (the caudal gap) have been inferred for a few populations but appear inapplicable in others. 2,For Sternotherus odoratus (the Common Musk Turtle), the pelvic aperture was always wider than the width of the female's largest egg by at least 3·7 mm. The caudal gap was narrower than the widest egg for 25·7% of the females. 3,Egg width increased, and elongation (length/width) decreased, as female size and clutch size increased. 4,Females at three ecologically contrasting sites differed appreciably in size but produced eggs of the same mean shape and size, despite the strong within-site changes in both egg size and shape with female size. As the younger females at all sites were of similar age and produced eggs of similar size and shape (again, despite differences in body size), egg size and shape may be age-specific. 5,No optimal egg size prevailed but the scaled residuals of egg size with female mass were less variable than were those for clutch size. [source] Health status and labour force participation: evidence from AustraliaHEALTH ECONOMICS, Issue 3 2006Lixin Cai Abstract This paper examines the effect of health on labour force participation using the Household, Income and Labour Dynamics in Australia (HILDA) Survey. The potential endogeneity of health, especially self-assessed health, in the labour force participation equation is addressed by estimating the health equation and the labour force participation equation simultaneously. Taking into account the correlation between the error terms in the two equations, the estimation is conducted separately for males aged 15,49, males aged 50,64, females aged 15,49 and females aged 50,60. The results indicate that better health increases the probability of labour force participation for all four groups. However, the effect is larger for the older groups and for women. As for the feedback effect, it is found that labour force participation has a significant positive impact on older females' health, and a significant negative effect on younger males' health. For younger females and older males, the impact of labour force participation on health is not significant. The null-hypothesis of exogeneity of health to labour force participation is rejected for all groups. Copyright © 2005 John Wiley & Sons, Ltd. [source] Risky weight control among university studentsINTERNATIONAL JOURNAL OF EATING DISORDERS, Issue 1 2006Hala Tamim PhD Abstract Objective The objectives of the current study were to investigate risky weight control measures (vomiting or pills) among university students in Lebanon and to assess their relation to demographic, scholastic, and health risk behavioral characteristics. Method The study used a cross-sectional design. A proportionate random sample of 2,013 students was selected from public and private universities in Greater Beirut. Each participant completed a self-administered anonymous questionnaire. Results Among participating students, 123 (6.1%) reported practicing risky weight control measures. Multivariate analysis indicated that younger females, cigarette smokers, engaged/married students, and those with a higher body mass index (BMI) were at increased odds of performing risky weight control measures. Conclusion Health awareness measures need to be proposed and, if possible, implemented to better define the motives and methods of weight reduction among Lebanese youth. © 2005 by Wiley Periodicals, Inc. [source] The role of males in the dynamics of ungulate populationsJOURNAL OF ANIMAL ECOLOGY, Issue 6 2002Atle Mysterud Summary 1In this review, we focus on how males can affect the population dynamics of ungulates (i) by being a component of population density (and thereby affecting interpretation of log-linear models), and (ii) by considering the mechanisms by which males can actively affect the demographic rates of females. 2We argue that the choice of measure of density is important, and that the inclusion or exclusion of males into models can influence results. For example, we demonstrate that if the dynamics of a population can be described with a first-order auto-regressive process in a log-linear framework, the asymmetry between the effects of females on the male dynamics and vice versa can introduce a second order process, much in the same way that the interaction between disease and host or predator and prey can. It would be useful for researchers with sufficient data to explore the affects of using different density measures. 3In general, even in harvested populations with highly skewed sex ratios, males are usually able to fertilize all females, though detailed studies document a lower proportion of younger females breeding when sex ratios are heavily female biased. It is well documented that the presence of males can induce oestrus in females, and that male age may also be a factor. In populations with both a skewed sex ratio and a young male age structure, calving is delayed and less synchronous. We identify several mechanisms that may be responsible for this. 4Delayed calving may lower summer survival and autumn masses, which may lead to higher winter mortality. If females are born light, they may require another year of growth before they start reproducing. Delayed calving can reduce future fertility of the mother. As the proportion of calves predated during the first few weeks of life is often very high, calving synchrony may also be an important strategy to lower predation rates. 5We argue that the effects of males on population dynamics of ungulates are likely to be non-trivial, and that their potential effects should not be ignored. The mechanisms we discuss may be important , though much more research is required before we can demonstrate they are. [source] High Bone Mass in a Female Hutterite PopulationJOURNAL OF BONE AND MINERAL RESEARCH, Issue 8 2000Karen S. Wosje Abstract We examined a Hutterite population (n = 243) to determine if their agriculturally diverse, self-sufficient communal lifestyle promotes optimal bone mass attainment because of adequate calcium intake and high physical activity levels during growth and young adulthood. We measured total body (TB) and lumbar bone mineral content (BMC) and bone mineral density (BMD) in 39 school-age (younger) females and 204 working (older) females. Forty-five percent of older females and 79% of younger females currently consumed ,3 servings (svg) of dairy per day. Older females had lumbar (0.6 ± 1.3) and TB (1.1 ± 1.1) BMD Z scores greater than 0 (both, p < 0.001). The lumbar BMD Z score of younger females was not different from 0 (,0.1 ± 1.0; p = 0.5). Both lumbar (r = 0.46; p < 0.001) and TB (r = 0.20; p = 0.02) BMD Z scores increased with increasing age. In multiple regression analyses for older females, lumbar bone area (p < 0.001), weight (p < 0.001), current hours on feet per day (p = 0.01), colony workload (p < 0.01), and estrogen status (p = 0.06) predicted lumbar BMC. TB bone area (p < 0.001), current hours on feet per day (p < 0.01), and colony workload (p < 0.01) predicted TB BMC. For younger females, lumbar bone area (p < 0.001), weight (p < 0.01), years in present colony (p = 0.02), and menses (p < 0.001) predicted lumbar BMC. TB bone area (p < 0.001), height (p < 0.01), years in present colony (p = 0.03), and menses (p < 0.01) predicted TB BMC. The effect of colony workload could not be separated from other factors different by colony. A heritability estimate of 0.66 was calculated for lumbar BMD using mother and daughter Z scores. Adequate calcium intake during growth, high physical activity early in life, and genetic factors may be contributing to above normal BMD levels in adult female Hutterites. [source] Association between TNFA-308 G/A polymorphism and sensitization to para- phenylenediamine: a case,control studyALLERGY, Issue 2 2009B. Blömeke Background:,Para -phenylenediamine (PPD) and related chemicals are common contact sensitizers, frequently causing allergic contact dermatitis (ACD). The cytokine tumor necrosis factor-alpha (TNF-,) plays a key role in contact sensitization. Methods:, In this case,control study, we evaluated the distribution of variations in the regulatory region of the gene for TNF-, (TNFA-308 G/A) in 181 Caucasian individuals with a history of ACD and sensitization to PPD and 161 individuals with no history of sensitization to PPD. Results:, The frequency of GA or AA TNFA genotypes was significantly higher in individuals sensitized to PPD than in age- and gender-matched controls giving an odds ratio (OR) of 2.16 (95% confidence interval, CI: 1.35,3.47; P = 0.0016). This relation was even more pronounced when restricting cases to females over 45 years (OR = 3.71; 95% CI: 1.65,8.31; P = 0.0017) vs younger females (less than or equal to 45 years; OR = 2.41; 95% CI: 1.03,5.65; P = 0.044) or males (OR = 1.05; 95% CI: 0.449,2.47; P = 1.0). In addition, a logistic regression model revealed a significant effect for TNFA-308 AA and AG vs GG genotype (point estimate = 2.152; 95% Wald CI: 1.332,3.477). Conclusions:, These findings suggest a possible role for the TNFA-308 genetic polymorphism as a susceptibility factor for chemically induced ACD. [source] Hypothesis: Could Epstein-Barr virus play a role in the development of gastroschisis?BIRTH DEFECTS RESEARCH, Issue 2 2010Martha M. Werler BACKGROUND: The strong inverse association between maternal age and risk of gastroschisis in offspring has spurred many investigators to hypothesize that behaviors among younger females are the cause. Examples include cigarette smoking, illicit drugs, genitourinary infections, and sexually transmitted diseases, each of which has been reported to be associated with gastroschisis. Although these exposures are more common in young women, recent studies have shown that cigarette smoking, genitourinary infections, and sexually transmitted diseases are most strongly associated with gastroschisis in older women. There is both anecdotal and published evidence showing that gastroschisis sometimes (but not always) occurs in clusters, raising the possibility that an infectious agent might be involved in its pathogenesis. RESULTS: One such agent whose epidemiologic characteristics parallel those of gastroschisis is Epstein-Barr virus (EBV). Primary EBV infection in early childhood has been decreasing over time, leaving a greater proportion of adolescents at risk, as reflected by increased rates of infectious mononucleosis over time. During the childbearing years, risk of primary EBV infection decreases dramatically, as does risk of gastroschisis. The stronger risks of gastroschisis associated with cigarette smoking, genitourinary infections, and sexually transmitted diseases in older women might be explained by EBV reactivation resulting from multiple challenges to immune response such as pregnancy, age, toxic exposures, and genitourinary and sexually transmitted infections. CONCLUSION: EBV and other herpes viruses should be added to the research agenda for gastroschisis. Birth Defects Research (Part A) 2010. © 2009 Wiley-Liss, Inc. [source] | |||||||||||||