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81.
Kajsa Sjöholm Björn Carlsson Lena MS Carlsson 《Central European Journal of Biology》2006,1(2):221-234
The leptin system regulates body fat mass through a feedback loop between adipose tissue and the hypothalamus. To test if
leptin responsiveness may be regulated we assayed hypothalamic response to leptin during the estrous cycle; when changes in
food intake are known to occur. Immature rats were treated with pregnant mare’s serum gonadotropin (PMSG) to induce synchronized
follicular development, ovulation and corpus luteum formation. Leptin response was estimated by measuring the in vitro induction of tis11, a primary response gene activated by STAT3-dependent cytokines in hypothalamic explants after leptin stimulation. In addition,
mRNA levels of the suppressor cytokine signaling-3 (SOCS-3), a possible mediator of leptin resistance, were analyzed. Serum
leptin levels did not change between days 2 and day 3 (corresponding to proestrus and estrus, respectively) but the response
to leptin was higher on day 2 than on day 3 (p=0.05). Food intake displayed a tendency towards downregulation between day
1 and day 2 (p=0.057), and a tendency towards upregulation between day 2 and day 3 (p=0.072), although the body weight increased
on day of the study (p<0.0001). There was no significant difference in hypothalamic expression of SOCS-3 between day 2 and
day 3. In conclusion, we have shown that leptin responsiveness changes during a hormonally induced estrous cycle in rats.
Our data suggest that a change in the hypothalamic response to leptin may cause the cyclic feeding behavior seen in rats. 相似文献
82.
83.
Background
Climate-induced coral bleaching poses a major threat to coral reef ecosystems, mostly because of the sensitivities of key habitat-forming corals to increasing temperature. However, susceptibility to bleaching varies greatly among coral genera and there are likely to be major changes in the relative abundance of different corals, even if the wholesale loss of corals does not occur for several decades. Here we document variation in bleaching susceptibility among key genera of reef-building corals in Moorea, French Polynesia, and compare bleaching incidence during mass-bleaching events documented in 1991, 1994, 2002 and 2007.Methodology/Principal Findings
This study compared the proportion of colonies that bleached for four major genera of reef-building corals (Acropora, Montipora, Pocillopora and Porites), during each of four well-documented bleaching events from 1991 to 2007. Acropora and Montipora consistently bleached in far greater proportions (up to 98%) than Pocillopora and Porites. However, there was an apparent and sustained decline in the proportion of colonies that bleached during successive bleaching events, especially for Acropora and Montipora. In 2007, only 77% of Acropora colonies bleached compared with 98% in 1991. Temporal variation in the proportion of coral colonies bleached may be attributable to differences in environmental conditions among years. Alternately, the sustained declines in bleaching incidence among highly susceptible corals may be indicative of acclimation or adaptation.Conclusions/Significance
Coral genera that are highly susceptible to coral bleaching, and especially Acropora and Montipora, exhibit temporal declines in their susceptibility to thermal anomalies at Moorea, French Polynesia. One possible explanation for these findings is that gradual removal of highly susceptible genotypes (through selective mortality of individuals, populations, and/or species) is producing a coral assemblage that is more resistant to sustained and ongoing ocean warming. 相似文献84.
Kemmer D Huang Y Shah SP Lim J Brumm J Yuen MM Ling J Xu T Wasserman WW Ouellette BF 《Genome biology》2005,6(12):R106
We developed Ulysses as a user-oriented system that uses a process called Interolog Analysis for the parallel analysis and
display of protein interactions detected in various species. Ulysses was designed to perform such Interolog Analysis by the
projection of model organism interaction data onto homologous human proteins, and thus serves as an accelerator for the analysis
of uncharacterized human proteins. The relevance of projections was assessed and validated against published reference collections.
All source code is freely available, and the Ulysses system can be accessed via a web interface . 相似文献
85.
86.
Lazos-Monterrosa FA C Orantes-García O Farrera-Sarmiento AG Verdugo-Valdez MS Sánchez-Cortés LE Ruíz-Meza 《Phyton》2015,84(1):138-143
The tempisque (Sideroxylon capiri) is a tree native to Mexico used by the rural population for housing construction, poles and hedges, as fuel (wood) and also for fodder and ornamental purposes, among others. It is considered an endangered species. In order to contribute to its preservation and sustainable management, it was considered important to determine the proportion of viable seeds, the loss of viability due to storage period and the germination process by applying pregerminative treatments. We found that freshly collected seeds showed 100% viability, which decreased to 0% after 5 months of storage. According to the cumulative germination significant differences between treatments (p≤0.01) were found. It was observed that seeds can accelerate their time of germination with the previous exposure of 24 h in water at room temperature. The soaking treatment in water for 24 h at room temperature obtained final germination of 55%, while with the control 39% was reached. Soaking in hydrogen peroxide and scarification were the treatments with lower germination percentage (33 and 23%, respectively). To get a higher percentage of germinated seeds in a short time, it is necessary to give a soaking treatment in water for 24 h before sowing. 相似文献
87.
88.
Background
Adverse drug reactions (ADRs) are now recognized as an important cause of hospital admissions, with a proportion ranging from 0.9–7.9%. They also constitute a significant economic burden. We thus aimed at determining the prevalence and the economic burden of ADRs presenting to Medical Emergency Department (ED) of a tertiary referral center in India 相似文献89.
Elina MS Paaso Maritta S Jaakkola Aino K Rantala Timo T Hugg Jouni JK Jaakkola 《Respiratory research》2014,15(1)
BackgroundFamily history of asthma and other allergic diseases have been linked to the risk of childhood asthma previously, but little is known about their effect on the age-of-onset and persistency of asthma until young adulthood.MethodsWe assessed the effect of the family history of asthma and allergic diseases on persistent vs. transient, and early- vs. late-onset persistent asthma in The Espoo Cohort Study 1991–2011, a population-based cohort study of 1623 subjects (follow-up rate 63.2%). The determinants were any family history (any parent or sibling); maternal; paternal; siblings only; parents only; and both siblings and parents. Analyses were conducted separately for asthma and allergic diseases while taking the other disease into account as a confounding factor. The outcomes were persistent, transient, early-onset persistent (<13 years) and late-onset persistent asthma. Adjusted risk ratios (RR) were calculated applying Poisson regression. Q-statistics were used to assess heterogeneity between RRs.ResultsFamily history was associated with the different subtypes but the magnitude of effect varied quantitatively. Any family history of asthma was a stronger determinant of persistent (adjusted RR = 2.82, 95% CI 1.99-4.00) than transient asthma (1.65, 1.03-2.65) (heterogeneity: P = 0.07) and on early-onset than late-onset persistent asthma. Also any family history of allergic diseases was a stronger determinant of persistent and early-onset asthma. The impact of paternal asthma continued to young adulthood (early-onset: 3.33, 1.57-7.06 vs. late-onset 2.04, 0.75-5.52) while the influence of maternal asthma decreased with age (Early-onset 3.94, 2.11-7.36 vs. Late-onset 0.88, 0.28-2.81). Paternal allergic diseases did not follow the pattern of paternal asthma, since they showed no association with late-onset asthma. Also the effect estimates for other subtypes were lower than in other hereditary groups (persistent 1.29, 0.75-2.22 vs. transient 1.20, 0.67-2.15 and early-onset 1.86, 0.95-3.64 vs. late-onset 0.64, 0.22-1.80).ConclusionsFamily history of asthma and allergic diseases are strong determinants of asthma, but the magnitude of effect varies according to the hereditary group so that some subtypes have a stronger hereditary component, and others may be more strongly related to environmental exposures. Our results provide useful information for assessing the prognosis of asthma based on a thorough family history. 相似文献
90.
Raynner RD Barboza Wedson de MS Souto José da S Mourão 《Journal of ethnobiology and ethnomedicine》2007,3(1):1-14