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991.
T. Zhao B. M. Chen X. M. Zhao Z. Y. Shan 《Reproductive biology and endocrinology : RB&E》2018,16(1):111
Background
To assess whether elevated thyroid-stimulating hormone (TSH) levels before conception can predict poor outcomes of assisted reproductive technology (ART).Methods
Prior to July 2018, we searched the PubMed, EMBASE, COCHRANE, Google Scholar, and CNKI databases for studies. Retrospective or prospective reports that compared ART results in patients with subclinical hypothyroidism (SCH) with normal thyroid function were selected. Two reviewers separately reviewed each potential article for qualification, analyzed the quality of the studies according to the Newcastle-Ottawa scale, and extracted the data. The PRISMA guidelines were adopted.Results
We selected a total of 18 publications that included 14,846 participants for this meta-analysis. When the TSH cut-off value for SCH was set at 2.5 mIU/L, no significant differences were observed in ART-related outcomes between SCH patients and normal women. The evaluated outcomes included the live birth rate (LBR) (OR: 0.93; 95% CI (0.77,1.12), P =?0.43), clinical pregnancy rate (CPR) (OR:1.02; 95% CI (0.90,1.17); P =?0.74), pregnancy rate (PR) (OR: 1.00; 95% CI (0.89,1.12); P =?0.99), and miscarriage rate (MR) (OR:1.24; 95% CI (0.85, 1.80); P =?0.26). Furthermore, when a higher TSH level was used as the cut-off value to diagnose SCH (i.e., 3.5–5 mIU/L), a significant difference was found in the MR (OR: 1.91; 95% CI (1.09, 3.35); P =?0.02) between the two groups of ART-treated women. However, when a broader cut-off value was used to define SCH, no significant differences were observed in the LBR (OR: 0.72; 95% CI (0.47,1.11); P =?0.14), CPR (OR: 0.82; 95% CI (0.66,1.00); P =?0.052), or PR (OR: 1.07; 95% CI (0.72,1.60); P =?0.74) between the two groups of ART-treated women.Conclusion
No difference was observed in ART outcomes when a TSH cut-off value of 2.5 mIU/L was used. However, when a broader TSH cut-off value was used, preconception SCH resulted in a higher miscarriage rate than in normal women.992.
Systematic Evaluation of Protein Sequence Filtering Algorithms for Proteoform Identification Using Top‐Down Mass Spectrometry 下载免费PDF全文
Complex proteoforms contain various primary structural alterations resulting from variations in genes, RNA, and proteins. Top‐down mass spectrometry is commonly used for analyzing complex proteoforms because it provides whole sequence information of the proteoforms. Proteoform identification by top‐down mass spectral database search is a challenging computational problem because the types and/or locations of some alterations in target proteoforms are in general unknown. Although spectral alignment and mass graph alignment algorithms have been proposed for identifying proteoforms with unknown alterations, they are extremely slow to align millions of spectra against tens of thousands of protein sequences in high throughput proteome level analyses. Many software tools in this area combine efficient protein sequence filtering algorithms and spectral alignment algorithms to speed up database search. As a result, the performance of these tools heavily relies on the sensitivity and efficiency of their filtering algorithms. Here, we propose two efficient approximate spectrum‐based filtering algorithms for proteoform identification. We evaluated the performances of the proposed algorithms and four existing ones on simulated and real top‐down mass spectrometry data sets. Experiments showed that the proposed algorithms outperformed the existing ones for complex proteoform identification. In addition, combining the proposed filtering algorithms and mass graph alignment algorithms identified many proteoforms missed by ProSightPC in proteome‐level proteoform analyses. 相似文献
993.
The temperature dependences of net photosynthetic rate (P
N), stomatal conductance (g
s), transpiration rate (E) and dark respiration (R
D) of four neem (Azadirachta indica A. Juss) provenances of 11 years old were measured in three seasons of 2006 in the dry-hot valley area of southwest China
under field conditions. The results indicated that P
N of four neem provenances showed clear parabolic responses with the increase of temperature. The optimum temperature of P
N was around 25°C in initiation stage and 30°C in prosperous stage except for neem originating from Jodhpur (MA) provenance
which was very close to the mean daily temperature of the preceding week while it was around 27°C (MA provenance excepted)
in last stage which was rather close to the mean daily maximum temperature of the preceding week. The optimum temperature
for P
N of MA provenance was about 2–4°C higher than that of the other three neem provenances in prosperous stage and last stage.
According to the fitted parameters of photosynthetic temperature response curves, the photosynthetic performance in prosperous
stage was more sensitive to temperature changes than that in initiation stage and last stage while the photosynthetic performance
of neem originating from MA provenance was less sensitive to temperatures than that of neem originating from Kalyani, New
Delhi and Kulapachta provenances in each growing stage. Furthermore, the temperature ranges for P
N of MA provenance were much wider than those of the remaining provenances in each growing stage. These differences in photosynthetic
temperature acclimation between neem provenances not only reflected temperature regime of native habitats of these provenances
but suggested that MA provenance could be more tolerant to extreme temperatures compared with the remaining provenances. The
temperature response curves of g
s and E were generally similar in form in the same growing stage for all neem provenances; however, shape of the response curves
in initiation stage and last stage was similar to parabolic curve while that in prosperous stage was similar to linear relation.
The temperature for maximum g
s and E in initiation stage was close to the optimum temperature of P
N, but the maximum g
s reached at much lower temperature than P
N and E in last stage. The response of R
D to temperature increased exponentially with temperature; however, there were obvious differences in different growing stages.
R
D in initiation stage was markedly higher than that in prosperous stage and last stage at a given temperature for four neem
provenances. These results suggested that four neem provenances can acclimate to their growing environment through changed
photosynthetic ecophysiological responses in course of subjecting to seasonal variation of temperature. 相似文献
994.
Characterization and functional analysis of hsp21.8b: An orthologous small heat shock protein gene in Tribolium castaneum 下载免费PDF全文
J. Xie W. Xiong X. Hu S. Gu S. Zhang S. Gao X. Song J. Bi B. Li 《Journal of Applied Entomology》2018,142(7):654-666
Small heat shock proteins (sHSPs) act as molecular chaperones and are widely distributed in all kinds of organisms. Comparative analysis revealed that an orthologous shsp was present during insect evolution. Here, hsp21.8b, one insect orthologous shsp, had been identified in Tribolium castaneum. Quantitative real‐time PCR illustrated that Tchsp21.8b was expressed in all developmental stages, along with the lowest expression at early embryonic stage and relative high expression at other stages especially in late eggs and late pupae. In the adult period, Tchsp21.8b exhibited the highest expression level in central nervous system and followed in elytron, epidermis, ovary and fat body. Moreover, it was upregulated 3.39‐fold in response to enhanced heat stress (45°C) for 4 hr but not to cold stress (4°C) and was upregulated by 1.73‐ to 1.94‐fold under ultraviolet (UV) exposure during 4–6 hr. It was also downregulated by 20.8%–41.8% under starvation in 3 days and had a “down‐up‐down” trend under the pathogen stresses. Larval RNA interference of Tchsp21.8b caused 40.6% insects mortality and reduced the oviposition amount by 66.0% and only 21.0% of the ds‐Tchsp21.8b eggs could hatch into larvae. These results suggested that as an orthologous shsp, Tchsp21.8b not only plays important roles in the growth, development and fecundity of T. castaneum but with the competence to resist the environment stresses, although the response is relatively weak compared to other hsps. Results from this study also uncovered the functions of the orthologous shsp in the development and anti‐stresses ability of T. castanuem. It provided more scientific evidence for revealing the physiological mechanisms of shsps of the insects and enhanced the capabilities to control different pests. 相似文献
995.
996.
J-S Zhang M Herreros-Vilanueva A Koenig Z Deng A A-M de Narvajas T S Gomez X Meng L Bujanda V Ellenrieder X K Li S H Kaufmann D D Billadeau 《Cell death & disease》2014,5(3):e1142
While TRAIL is a promising anticancer agent due to its ability to selectively induce
apoptosis in neoplastic cells, many tumors, including pancreatic ductal adenocarcinoma
(PDA), display intrinsic resistance, highlighting the need for TRAIL-sensitizing agents.
Here we report that TRAIL-induced apoptosis in PDA cell lines is enhanced by
pharmacological inhibition of glycogen synthase kinase-3 (GSK-3) or by shRNA-mediated
depletion of either GSK-3α or GSK-3β. In contrast, depletion
of GSK-3β, but not GSK-3α, sensitized PDA cell lines to
TNFα-induced cell death. Further experiments demonstrated that
TNFα-stimulated IκBα phosphorylation and
degradation as well as p65 nuclear translocation were normal in
GSK-3β-deficient MEFs. Nonetheless, inhibition of GSK-3β
function in MEFs or PDA cell lines impaired the expression of the NF-κB
target genes Bcl-xL and cIAP2, but not IκBα. Significantly,
the expression of Bcl-xL and cIAP2 could be reestablished by expression of
GSK-3β targeted to the nucleus but not GSK-3β targeted to
the cytoplasm, suggesting that GSK-3β regulates NF-κB
function within the nucleus. Consistent with this notion, chromatin immunoprecipitation
demonstrated that GSK-3 inhibition resulted in either decreased p65 binding to the
promoter of BIR3, which encodes cIAP2, or increased p50 binding as well as
recruitment of SIRT1 and HDAC3 to the promoter of BCL2L1, which encodes Bcl-xL.
Importantly, depletion of Bcl-xL but not cIAP2, mimicked the sensitizing effect of GSK-3
inhibition on TRAIL-induced apoptosis, whereas Bcl-xL overexpression ameliorated the
sensitization by GSK-3 inhibition. These results not only suggest that
GSK-3β overexpression and nuclear localization contribute to TNFα
and TRAIL resistance via anti-apoptotic NF-κB genes such as Bcl-xL, but
also provide a rationale for further exploration of GSK-3 inhibitors combined with TRAIL
for the treatment of PDA. 相似文献
997.
998.
Chang Wang Yaqin Yu Xiangyang Zhang Yong Li Changgui Kou Bo Li Yuchun Tao Qing Zhen Huan He Joseph Sam Kanu Xufeng Huang Mei Han Yawen Liu 《PloS one》2014,9(7)
Background
The awareness, treatment and control of diabetes mellitus (DM) can effectively reflect on the social status of diabetes conditions. Although several researchers have investigated the awareness, treatment and control rates of diabetes mellitus in China, little is known about their association with risk factors. This study aims to examine the relationship between risk factors and awareness, treatment and control of diabetes mellitus in northeast China.Methods
A cross-sectional survey was conducted in 2012. Multistage stratified random cluster sampling design was used to select participants aged 18 to 79 years old. The analysis was based on a representative sample of 1,854 adult subjects. Multivariable logistic regression analysis was used to examine socio-demographic factors associated with the levels of awareness, treatment and control of diabetes mellitus.Results
The awareness, treatment, and control rates of diabetes mellitus were 64.1%, 52.9% and 44.2%, respectively. In the multivariable logistic regression analysis, family history of diabetes was significantly positively associated with awareness (OR, 2.145; 95% CI, 1.600–2.875) and treatment (OR, 2.021; 95% CI, 1.559–2.619) of diabetes mellitus, while negatively associated with control (OR, 0.671; 95% CI, 0.529–0.951). Cigarette smokers and alcohol drinkers were less likely than non-smokers and non-drinkers to be aware of their blood glucose levels (OR, 0.895, 0.614; 95% CI, 0.659–1.216, 0.446–0.844, respectively). Participants who frequently exercise were more likely to be aware of their diabetic conditions than people who never or rarely exercise (OR, 2.003; 95% CI, 1.513–2.651).Conclusions
We found that the awareness and treatment of diabetes mellitus were positively associated with age and were high in participants with a family history of diabetes and those who exercise frequently, but low for cigarette smokers and alcohol drinkers. Participants with a family history of diabetes had their diabetic condition poorly controlled. 相似文献999.
P. F. Hendrix G. H. Baker M. A. Callaham Jr G. A. Damoff C. Fragoso G. González S. W. James S. L. Lachnicht T. Winsome X. Zou 《Biological invasions》2006,8(6):1287-1300
The most conspicuous biological invasions in terrestrial ecosystems have been by exotic plants, insects and vertebrates. Invasions by exotic earthworms, although not as well studied, may be increasing with global commerce in agriculture, waste management and bioremediation. A number of cases has documented where invasive earthworms have caused significant changes in soil profiles, nutrient and organic matter dynamics, other soil organisms or plant communities. Most of these cases are in areas that have been disturbed (e.g., agricultural systems) or were previously devoid of earthworms (e.g., north of Pleistocene glacial margins). It is not clear that such effects are common in ecosystems inhabited by native earthworms, especially where soils are undisturbed. We explore the idea that indigenous earthworm fauna and/or characteristics of their native habitats may resist invasion by exotic earthworms and thereby reduce the impact of exotic species on soil processes. We review data and case studies from temperate and tropical regions to test this idea. Specifically, we address the following questions: Is disturbance a prerequisite to invasion by exotic earthworms? What are the mechanisms by which exotic earthworms may succeed or fail to invade habitats occupied by native earthworms? Potential mechanisms could include (1) intensity of propagule pressure (how frequently and at what densities have exotic species been introduced and has there been adequate time for proliferation?); (2) degree of habitat matching (once introduced, are exotic species faced with unsuitable habitat conditions, unavailable resources, or unsuited feeding strategies?); and (3) degree of biotic resistance (after introduction into an otherwise suitable habitat, are exotic species exposed to biological barriers such as predation or parasitism, “unfamiliar” microflora, or competition by resident native species?). Once established, do exotic species co-exist with native species, or are the natives eventually excluded? Do exotic species impact soil processes differently in the presence or absence of native species? We conclude that (1) exotic earthworms do invade ecosystems inhabited by indigenous earthworms, even in the absence of obvious disturbance; (2) competitive exclusion of native earthworms by exotic earthworms is not easily demonstrated and, in fact, co-existence of native and exotic species appears to be common, even if transient; and (3) resistance to exotic earthworm invasions, if it occurs, may be more a function of physical and chemical characteristics of a habitat than of biological interactions between native and exotic earthworms. 相似文献
1000.