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61.
62.
Climate change may shift interactions of invasive plants, herbivorous insects and native plants, potentially affecting biological control efficacy and non‐target effects on native species. Here, we show how climate warming affects impacts of a multivoltine introduced biocontrol beetle on the non‐target native plant Alternanthera sessilis in China. In field surveys across a latitudinal gradient covering their full distributions, we found beetle damage on A. sessilis increased with rising temperature and plant life history changed from perennial to annual. Experiments showed that elevated temperature changed plant life history and increased insect overwintering, damage and impacts on seedling recruitment. These results suggest that warming can shift phenologies, increase non‐target effect magnitude and increase non‐target effect occurrence by beetle range expansion to additional areas where A. sessilis occurs. This study highlights the importance of understanding how climate change affects species interactions for future biological control of invasive species and conservation of native species. 相似文献
63.
64.
A novel colorimetric fluoride sensor based on a semi‐rigid chromophore controlled by hydrogen bonding 下载免费PDF全文
A novel semi‐rigid latent chromophore E1, containing an amide subunit activated by an adjacent semi‐rigid intramolecular hydrogen‐bonding (IHB) unit, was designed for the detection of fluoride ion by the ‘naked‐eye’ in CH3CN. Comparative studies on structural analogs (E2, E3, and E4) provided significant insight into the structural and functional role of the amide N–H and IHB segment in the selective recognition of fluoride ions. The deprotonation of the amide N–H followed by the enhancement of intramolecular charge transfer (ICT) induced the colorimetric detection of E1 for fluoride ion. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
65.
Plk1 has been essentially described as a critical regulator of many mitotic events. However, increasing evidence supports the notion that its molecular functions are not restricted to the cell cycle. In particular, recent reports suggest the existence of a molecular and functional link between Plk1 and the mammalian target of rapamycin (mTOR) pathway, which controls cell growth and proliferation via the raptor-mTOR (TORC1) and rictor-mTOR (TORC2) protein complexes. Herein, we have identified rapamycin-insensitive companion of mTOR (Rictor), a core component of mTORC2, as a new Plk1 substrate and have shown that Plk1 phosphorylates Rictor at Ser1162 in vitro and in vivo. Surprisingly, cells expressing the unphosphorylatable mutant (S1162A) of Rictor did not show any effect on well characterized canonical PI3K-mTOR pathway. However, we found that cells expressing the unphosphorylatable form of Rictor have an elevated level of mSin1 isoform (mSin1.5). Considering that mSin1.5-containing mTORC2 was reported to associate with stress signaling, we propose that phosphorylation of Rictor at Ser1162 by Plk1 might be involved in a novel signaling pathway by regulating the mSin1.5-defined mTORC2. 相似文献
66.
Junhong Leng Ping Shao Cuiping Zhang Huiguang Tian Fuxia Zhang Shuang Zhang Ling Dong Lili Li Zhijie Yu Juliana C. N. Chan Gang Hu Xilin Yang 《PloS one》2015,10(3)
Objective
We compared the increases in the prevalence of gestational diabetes mellitus (GDM) based on the 1999 World Health Organization (WHO) criteria and its risk factors in Tianjin, China, over a 12-year period. We also examined the changes in the prevalence using the criteria of International Association of Diabetes and Pregnancy Study Group (IADPSG).Methods
In 2010-2012, 18589 women who registered within 12 weeks of gestation underwent a glucose challenge test (GCT) at 24-28 gestational weeks. Amongst them, 2953 women with 1-hour plasma glucose ≥7.8 mmol/L underwent a 75-gram 2-hour oral glucose tolerance test (OGTT) and 781 women had a positive GCT but absented from the standard OGTT. An adjusted prevalence of GDM was calculated for the whole cohort of women by including an estimate of the proportion of women with positive GCTs who did not have OGTTs but would have been expected to have GDM. Logistic regression was used to obtain odds ratios and 95% confidence intervals using the IADPSG criteria. The prevalence of GDM risk factors was compared to the 1999 survey.Results
The adjusted prevalence of GDM by the 1999 WHO criteria was 8.1%, a 3.5-fold increase as in 1999. Using the IADPSG criteria increased the adjusted prevalence further to 9.3%. Advanced age, higher pre-pregnancy body mass index, Han-nationality, higher systolic blood pressure (BP), a family history of diabetes, weight gain during pregnancy and habitual smoking were risk factors for GDM. Compared to the 1999 survey, the prevalence of overweight plus obesity had increased by 1.8 folds, age≥30 years by 2.3 folds, systolic BP by 2.3 mmHg over the 12-year period.Conclusions
Increasing prevalence of overweight/obesity and older age at pregnancy were accompanied by increasing prevalence of GDM, further increased by change in diagnostic criteria. 相似文献67.
Feng Zhi Qiang Wang Lian Xue Naiyuan Shao Rong Wang Danni Deng Suinuan Wang Xiwei Xia Yilin Yang 《PloS one》2015,10(8)
Long noncoding RNAs (lncRNAs) are pervasively transcribed and play a key role in tumorigenesis. The aim of the study was to determine the lncRNA expression profile in astrocytomas and to assess its potential clinical value. We performed a three-step analysis to establish the lncRNA profile for astrocytoma: a) the lncRNA expression was examined on 3 astrocytomas as well as 3 NATs (normal adjacent tissues) using the lncRNA microarray; b) the top-hits were validated in 40 astrocytomas (WHO grade II-IV) by quantitative real time-PCR (qRT-PCR); c) the hits with significant differences were re-evaluated using qRT-PCR in 90 astrocytomas. Finally, 7 lncRNAs were found to have a significantly different expression profile in astrocytoma samples compared to the NAT samples. Unsupervised clustering analysis further revealed the potential of the 7-lncRNA profile to differentiate between tumors and NAT samples. The upregulation of ENST00000545440 and NR_002809 was associated with advanced clinical stages of astrocytoma. Using Kaplan-Meier survival analysis, we showed that the low expression of BC002811 or XLOC_010967, or the high expression of NR_002809 was significantly associated with poor patient survival. Moreover, Cox proportional hazard regression analysis revealed that this prognostic impact was independent of other clinicopathological factors. Our results indicate that the lncRNA profile may be a potential prognostic biomarker for the prediction of post-surgical outcomes. 相似文献
68.
Warming-induced drought has widely affected forest dynamics in most places of the northern hemisphere. In this study, we assessed how climate warming has affected Picea crassifolia (Qinghai spruce) forests using tree growth-climate relationships and the normalized difference vegetation index (NDVI) along the Qilian Mountains, northeastern Tibet Plateau (the main range of Picea crassifolia). Based on the analysis on trees radial growth data from the upper tree line and the regional NDVI data, we identified a pervasive growth decline in recent decades, most likely caused by warming-induced droughts. The drought stress on Picea crassifolia radial growth were expanding from northeast to southwest and the favorable moisture conditions for tree growth were retreating along the identical direction in the study area over the last half century. Compared to the historical drought stress on tree radial growth in the 1920s, recent warming-induced droughts display a longer-lasting stress with a broader spatial distribution on regional forest growth. If the recent warming continues without the effective moisture increasing, then a notable challenge is developed for Picea crassifolia in the Qilian Mountains. Elaborate forest management is necessary to counteract the future risk of climate change effects in this region. 相似文献
69.
Guoyu Jia Fusheng Di Qipeng Wang Jinshuang Shao Lei Gao Lu Wang Qiang Li Nali Li 《PloS one》2015,10(11)
Background
Non-alcoholic fatty liver disease (NAFLD) is prevalent in individuals with type 2 diabetes mellitus (T2DM). Diabetic nephropathy (DN) is also associated with T2DM. However, little is known about the interaction between these conditions in patients with T2DM.Objective
To examine the association between NAFLD and DN in patients with T2DM.Methods
This retrospective study included patients seen between January 2006 and July 2014.T2DM patients were divided into two groups based on NAFLD status (with NAFLD = group A; without = group B). The cumulative incidence of DN and chronic kidney disease (CKD) staging were compared between the two groups. Liver fat content was examined in some patients. Associations among NAFLD, other factors,and DN were analyzed by the additive interaction method.Results
Cumulative incidence of DN in patients from group A (58.58%) was higher than in group B (37.22%) (P = 0.005). In both groups, the number of DN patients with CKD stage 1 was greater than the number of patients with stages 2–5. Increased liver fat content was associated with increased occurrence of severe and mild albuminuria and decreased glomerular filtration rate (GFR). There were positive correlations between NAFLD and insulin resistance index (HOMA-IR), free fatty acids (FFA), tumor necrosis factor-α (TNF-α), omentin-1, visceral fat area, homocysteine (HCY), and serum uric acid (UA).Conclusion
NAFLD might be a risk factor for DN. Elevated liver fat content could be associated with higher DN burden. 相似文献70.
Five new guaiane sesquiterpenes, 1 – 5 , were isolated from the culture broth of the endophytic fungus Xylaria sp. YM 311647, isolated from Azadirachta indica A. Juss . The structures of these compounds were elucidated on the basis of spectroscopic analyses, and their inhibitory activities against five pathogenic fungi were evaluated. All guaiane sesquiterpenes showed moderate or weak antifungal activities in a broth microdilution assay. 相似文献