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11.
Yuanyuan Zhang Yuhui Zhang Chunmei Li Shuai Fu Chunfeng Yang Yan Song Meilan Liu Zhenhua Wang Peili Liang Jianping Zhang 《Cell biochemistry and function》2019,37(7):464-473
We sought to explore the functions and modulated factors of NOD1 in normal decidual stromal cells (DSCs) derived from the first trimester pregnancy and whether existed different expression of NOD1 between normal and unexplained recurrent pregnancy loss (URPL) in DSCs. Twenty‐six patients with normal pregnancies that required abortion and 12 URPL patients at first trimester were enrolled for the study. As a result, we found lower levels of NOD1 in the DSCs derived from URPL compared with those from normal early trimester pregnancy. Furthermore, increased NOD1 expression in the normal DSCs induced apoptosis and increased monocyte chemotactic protein‐1 (MCP‐1) and IL‐1β (interleukin 1 beta) secretion but decreased their invasion capacity. In addition, several cytokines such as IL‐1β, tumour necrosis factor‐alpha (TNF‐α), interferon‐gamma (IFN‐γ), and interleukin‐17 (IL‐17) were present at the maternal‐fetal interface in RPL and were found to regulate NOD1 expression in primary DSCs. Our study indicates that RPL may be associated with NOD1 aberrant expression in DSCs, which plays a significant role in maintaining pregnancy via infection control and regulation of immune responses that might affect the pregnancy outcome. We expect that our results will bring more comprehensively understanding about the connection between NOD1 and RPL for researchers. 相似文献
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Dennis T. Villareal Caroline M. Apovian Robert F. Kushner Samuel Klein 《Obesity (Silver Spring, Md.)》2005,13(11):1849-1863
Obesity causes serious medical complications and impairs quality of life. Moreover, in older persons, obesity can exacerbate the age‐related decline in physical function and lead to frailty. However, appropriate treatment for obesity in older persons is controversial because of the reduction in relative health risks associated with increasing body mass index and the concern that weight loss could have potential harmful effects in the older population. This joint position statement from the American Society for Nutrition and NAASO, The Obesity Society reviews the clinical issues related to obesity in older persons and provides health professionals with appropriate weight‐management guidelines for obese older patients. The current data show that weight‐loss therapy improves physical function, quality of life, and the medical complications associated with obesity in older persons. Therefore, weight‐loss therapy that minimizes muscle and bone losses is recommended for older persons who are obese and who have functional impairments or medical complications that can benefit from weight loss. 相似文献
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Alison M. Elliott Lorna S. Aucott Philip C. Hannaford W. Cairns Smith 《Obesity (Silver Spring, Md.)》2005,13(10):1784-1792
Objective: To investigate the relationship between weight change in adult life and subsequent mortality and cancer incidence in women. Research Methods and Procedures: In 1994 to 1995, all women (age range, 42 to 81) still under general practitioner observation in the United Kingdom's Royal College of General Practitioners Oral Contraception Study (n = 12 303) were sent a health survey asking about health and lifestyle issues, including current weight and weight at age 30. The main outcome measures were 6‐year all‐cause mortality and cancer incidence among different weight change deciles. Cox regression was used to calculate hazard ratios that were adjusted for: social class at recruitment, BMI at age 30, and age group, parity, smoking status, and hormone replacement therapy status in 1995. Results: Women who had been obese at age 30 were more likely to die and significantly more likely to develop cancer in the 6 years after the health survey than non‐obese respondents. Women reporting weight gains between age 30 and 1995 were significantly less likely to die during the 6 years after the health survey than those with a stable weight, whereas those with weight loss did not fare any better than those in the stable‐weight group. Discussion: Although obesity at young age was associated with subsequent mortality and cancer incidence, weight gain over a time period of 12 to 51 years appeared to be beneficial when compared with women with stable weight over the same time period. Further research is needed to confirm or refute our findings and to allow detailed examination of potential explanations for them. 相似文献
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Gerda Saxer Michael Doebeli Michael Travisano 《Proceedings. Biological sciences / The Royal Society》2009,276(1664):2065-2070
Spatial structure has been identified as a major contributor to the maintenance of diversity. Here, we show that the impact of spatial structure on diversity is strongly affected by the ecological mechanisms maintaining diversity. In well-mixed, unstructured environments, microbial populations can diversify by production of metabolites during growth, providing additional resources for novel specialists. By contrast, spatially structured environments potentially limit such facilitation due to reduced metabolite diffusion. Using replicate microcosms containing the bacterium Escherichia coli, we predicted the loss of diversity during an environmental shift from a spatially unstructured environment to spatially structured conditions. Although spatial structure is frequently observed to be a major promoter of diversity, our results indicate that it can also have negative impacts on diversity. 相似文献
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B. WERMELINGER A. RIGLING D. SCHNEIDER MATHIS M. DOBBERTIN 《Ecological Entomology》2008,33(2):239-249
Abstract. 1. In several dry inner Alpine valleys higher mortality levels of pine have been observed in recent years. This paper evaluates the role of xylophagous insects in the current pine decline and the influence of climate change on the infestation dynamics.
2. More than 200 trees of different levels of crown transparency (needle loss) were felled between 2001 and 2005 and sections of them incubated in insect emergence traps. Colonisation densities were related to the transparency level of each host tree at the time of attack.
3. Trees with more than 80% needle loss were colonised most frequently, but the breeding density was highest in trees with 65–80% needle loss.
4. The scolytine Ips acuminatus and the buprestid Phaenops cyanea colonised trees with 30–90% needle loss in high densities. The bark beetle Tomicus minor was less aggressive, preferring trees with 60–85% needle loss. The hymenopteran Sirex noctilio and the cerambycid Acanthocinus aedilis were restricted to greatly weakened trees with 50–85% needle loss. Most species colonised trees that had experienced a decline in vigour, that is an increase in crown transparency shortly before attack.
5. The infestation dynamics of P. cyanea covaried with the drought index as well as with temperature.
6. Increased temperatures not only trigger a drought stress rendering the host trees susceptible to insect attack, but also accelerate insect development. As more frequent drought periods are likely as a result of climate change, even trees only slightly or temporarily weakened will be more subject to attack by aggressive species such as I. acuminatus and P. cyanea . 相似文献
2. More than 200 trees of different levels of crown transparency (needle loss) were felled between 2001 and 2005 and sections of them incubated in insect emergence traps. Colonisation densities were related to the transparency level of each host tree at the time of attack.
3. Trees with more than 80% needle loss were colonised most frequently, but the breeding density was highest in trees with 65–80% needle loss.
4. The scolytine Ips acuminatus and the buprestid Phaenops cyanea colonised trees with 30–90% needle loss in high densities. The bark beetle Tomicus minor was less aggressive, preferring trees with 60–85% needle loss. The hymenopteran Sirex noctilio and the cerambycid Acanthocinus aedilis were restricted to greatly weakened trees with 50–85% needle loss. Most species colonised trees that had experienced a decline in vigour, that is an increase in crown transparency shortly before attack.
5. The infestation dynamics of P. cyanea covaried with the drought index as well as with temperature.
6. Increased temperatures not only trigger a drought stress rendering the host trees susceptible to insect attack, but also accelerate insect development. As more frequent drought periods are likely as a result of climate change, even trees only slightly or temporarily weakened will be more subject to attack by aggressive species such as I. acuminatus and P. cyanea . 相似文献
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