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Chinese Birds 2016年第2期7卷 125-131页

作者： Andrew Cantrell Lei Lv Yong Wang Jianqiang Li Zhengwang Zhang College of Agricultural Life and Natural Sciences Alabama A&M University School of life sciences Beijing Normal University

Background:The Hair-crested Drongo(Dicrurus hottentottus) exhibits a unique nest-dismantling behavior after the fledging of the *** hypothesis explaining this behavior is dismantling one's own nest may reduce potential competition for nest sites in the following breeding season because suitable breeding habitat might be limited,and sites are often ***:By comparing the habitat features at nest and random locations,we determined the nest habitat preference of the Hair-crested Drongo within Dongzhai National Nature Reserve,Henan,*** also compared habitat features with nesting success to determine if any trends could be ***:We found that nest tree height,diameter at breast height,live crown ratio,tree rank,and presence of overstory were significantly higher at nesting locations than random locations;slope,leaf litter cover percentage and depth,presence of understory and midstory,and number of trees per hectare were significantly lower at nest sites than random *** preferred to use some tree species,such as Metasequoia glyptostroboides,Castanea mollissima,and Pterocarya stenoptera for *** nests were often associated with habitat with higher percentage of leaf litter on the ***:Our data support that selection of nest sites does occur for this species at this site and therefore support the hypothesis that breeding habitat limitation could be one of the driving forces for the development of the nestdismantling behavior in this species.

关键词： Hair-crested Drongo Nest dismantling behavior Nest site selection China Dongzhai National Nature Reserve

BMP signaling in homeostasis, transformation and inflammatory response of intestinal epithelium

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Science China(life sciences) 2018年第7期61卷 800-807页

作者： Shan Wang Ye-Guang Chen The State Key Laboratory of Membrane Biology Tsinghua-Peking Center for Life Sciences School of Life Sciences Tsinghua University

Intestine is the organ for food digestion, nutrient absorption and pathogen defense, in which processes intestinal epithelium plays a central role. Intestinal epithelium undergoes fast turnover, and its homeostasis is regulated by multiple signaling pathways,including Wnt, Notch, Hippo and BMP pathways. BMP signaling has been shown to negatively regulate self-renewal of Lgr5^+ intestinal stem cells, constrains the expansion of intestinal epithelium, therefore attenuating colorectal cancer formation. BMPs and their receptors are expressed in both epithelial and mesenchymal cells, suggesting a two-way interaction between the mesenchyme and epithelium. In this review, we summarize the current understanding of the function of BMP signaling in homeostasis, cancerous transformation and inflammatory response of intestinal epithelium.

关键词： intestinal epithelium BMP signaling Smad ISC CRC

A Novel Model for Describing Rail Weld Irregularities and Predicting Wheel-Rail Forces Using a Machine Learning Approach

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Computer Modeling in Engineering & sciences 2025年第1期142卷 555-577页

作者： Linlin Sun Zihui Wang Shukun Cui Ziquan Yan Weiping Hu Qingchun Meng State Key Laboratory of High-Speed Railway Track System China Academy of Railway Sciences Corporation LimitedBeijing100081China Railway Engineering Research Institute China Academy of Railway Sciences Corporation LimitedBeijing100081China School of Aeronautic Science and Engineering Beihang UniversityBeijing100191China

Rail weld irregularities are one of the primary excitation sources for vehicle-track interaction dynamics in modern high-speed *** can cause significant wheel-rail dynamic interactions,leading to wheel-rail noise,component damage,and *** researchers have employed the vehicle-track interaction dynamic model to study the dynamic interactions between wheel and rail induced by rail weld geometry ***,the cosine wave model used to simulate rail weld irregularities mainly focuses on the maximum value and neglects the geometric *** this study,novel theoretical models were developed for three categories of rail weld irregularities,based on measurements of the high-speed railway from Beijing to *** vertical dynamic forces in the time and frequency domains were compared under different running *** forces generated by the rail weld irregularities that were measured and modeled,respectively,were compared to validate the accuracy of the proposed ***,based on the numerical study,the impact force due to rail weld irrregularity is modeled using an Artificial Neural Network(ANN),and the optimum combination of parameters for this model is *** results showed that the proposed model provided a more accurate wheel/rail dynamic evaluation caused by rail weld irregularities than that established in the *** ANN model used in this paper can effectively predict the impact force due to rail weld irrregularity while reducing the computation time.

关键词： Rail weld irregularity high-speed railway vehicle-track coupled dynamics wheel/rail dynamic vertical force artificial neural networks

Purification and characterization of rat testicular glutathione S-transferases:role in the synthesis of eicosanoids

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Asian Journal of Andrology 2000年第4期2卷 277-282页

作者： D.Anuradha K.VeeraReddy T.CharlesKumar S.Neeraja P.R.K.Reddy P.Reddanna School of life sciences University of Hyderabad Hyderabad-500 046 IndiaSchool of Life Sciences University of Hyderabad Hyderabad-500 046 IndiaSchool of Life Sciences University of Hyderabad Hyderabad-500 046 IndiaSchool of Life Sciences University of Hyderabad Hyderabad-500 046 IndiaSchool of Life Sciences University of Hyderabad Hyderabad-500 046 IndiaSchool of Life Sciences University of Hyderabad Hyderabad-500 046 India

Aim: Purification of glutathione S-transferases (GSTs) from rat testis; separation and identificationunits and their role in eicosanoid biosynthesis. Methods: Purification of mt testicular GSTs by affit?phy, employing S-hexylglutathione-linked epoxy-activated Sepharose 6B column and separation of indiby reverse phase-high pressure liquid chromatography (RP-HPLC). Characterization of affinity purified,um dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Westem blot analysis. The roGSTs in eicosanoid biosynthesis was determined by incubating GSTs with 5, 6-Leukotriene A_4Me (prostaglandin H_2 (PGH_2) and analyzing the products formed on HPLC/TLC. Results: The present stumajority of rat testicular GSTs are of Y_b size (60%) with molecular weight of 27 kDa. The most preunits, however, are GST Y_(n2) (27% ), followed by GST Y_c (24% ) and GST Y_(nl) (20%). These testiculavery high Leukotriene C_4 (LTC_4) synthase activity with 5, 6-Leukotriene A4Me (LTA_4Me) as theprostaglandin D (PGD) synthase activity with prostaglandin H_2 (PGH_2) as the substrate. Conclusion:testicular GSTs are Y_b sized and are involved in the synthesis of eicosanoids like LTC_4 and PGD_2.(Asian J Androl 2000 Dec; 2: 277-282)

关键词： testis glutathione transferase leukotrienes prostaglandins

Alpha-synuclein in mitochondrial dysfunction:opportunities or obstacles

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Neural Regeneration Research 2025年第1期20卷 197-198页

作者： Shermali Gunawardena Department of Biological sciences The State University of New York at BuffaloBuffaloNYUSA

Recent work suggests a link betweenα-synuclein(α-syn)and mitochondrial dysfunction;however,the mechanisms of howα-syn influences mitochondrial function are still *** notably,whetherα-syn plays a direct role during mitochondrial function and/or whether diseasedα-syn-mediated mitochondrial dysfunction is a potential modifiable risk factor in Parkinson’s disease(PD)is *** date,mutations in more than eight genes cause familial PD(fPD)and have functions in diverse pathways including synaptic homeostasis,mitochondria maintenance,autophagy/lysosome,and ubiquitin-proteasome pathways.

关键词： dysfunction homeostasis Alpha

Regional scientific research benefits threatened-species conservation

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National Science Review 2019年第6期6卷 1076-1079页

作者： Yisi Hu Zhenhua Luo Colin A.Chapman Stuart L.Pimm Samuel T.Turvey Michael J.Lawes Carlos A.Peres Tien Ming Lee Pengfei Fan School of life sciences Sun Yat-Sen University School of life sciences Central China Normal University Department of Anthropology and School of Environment Mc Gill University School of life sciences University of Kwa Zulu-Natal The College of life sciences Northwest University Nicholas School of the Environment Duke University

Although conventional wisdom considers knowledge of threatened species’ ecology and status essential for conservation, few studies demonstrate this in a quantitative way across many species and within the same political entity. Here,we evaluated the impacts of scientific research against conservation interventions(including funding) and specieslevel correlates, accounting for phylogenetic relatedness, on the conservation

关键词： China Regional scientific research benefits threatened-species conservation

Tadalafil treatment had a modest effect on endothelial cell damage and repair ability markers in men with erectile dysfunction and vascular risk

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Asian Journal of Andrology 2014年第2期16卷 290-294,I0011页

作者： Fiore Pelliccione Anatolia D'ngeli Settimio D'ndrea Arcangelo Barbonetti Alfonso Pezzella Stefano Necozione Stefano Falone Fernanda Amicarelli Felice Francavilla Sandro Francavilla Department of life Health and Environmental Sciences Section of Andrology Department of life Health and Environmental Sciences Section of Epidemiology Department of life Health and Environmental Sciences Section of Biological and Biotechnological Sciences University of UAquila L'Aquila Italy.

The number of the circulating angiogenic cells （CACs） and colony forming units （CFUs） derived from cultured circulating mononuclear cells （MNCs） represents a laboratory surrogate for endothelial cell repair ability. The serum of men with erectile dysfunction （ED） and vascular risk factors （VRFs） showed an increased level of endothelial cell damage/dysfunction markers and reduced the numbers of CACs and CFUs derived from the cells of healthy men. We analyzed whether treating men with ED and VRFs with the selective phosphodiesterase type 5 inhibitor tadalafil improved the endothelial cell repair ability and reduced the levels of the serum markers of endothelial cell damage/dysfunction. MNCs from healthy men were cultured with 20% serum from 36 ED patients to obtain CACs and CFUs. The ED patients were evaluated before and after 4weeks of treatment with tadalafil （20 mg every other day） or with a placebo. The tadalafil treatment improved erectile function （P = 0.0028）, but had no effect on the inhibitory effects of serum from ED patients on the CACs and CFUs derived from healthy men. The levels of endothelin-1 （P = 0.011） and tissue type plasminogen activator （P = 0.005） were reduced after treatment compared to baseline and those of the placebo group, whereas no changes were observed in the E-selectin levels. The tadalafil treatment in the ED patients with VRFs resulted in only a modest effect on the laboratory measures of the endothelial cell damage/dysfunction and repair ability. The proposed beneficial effect of phosphodiesterase type 5 inhibition on vascular homeostasis requires further analysis.

关键词： cardiovascular risk circulating angiogenic cells endothelial cell erectile dysfunction tadalafil

Microglial dysfunction and genetic risk for neurodegenerative disease

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Neural Regeneration Research 2025年第5期20卷 1401-1402页

作者： Debra S.MacDonald Jay Penney Department of Biomedical sciences AVCUniversity of Prince Edward IslandCharlottetownPECanada

Neurodegenerative disorders such as Alzheimer's and Parkinson's diseases a re increasing in prevalence as world populations *** tremendous progress has been made,our understanding of the mechanisms that underlie the development of these diseases remains far from com *** troubling,despite the growing emotional and financial toll being to ken by neurodegenerative disorders,existing treatment options are limited almost exclusively to those that help manage symptoms but that lack the ability to alter the progression of the disease(Liu et al.,2022).

关键词： degenerative diseases

Crystal structures of Bbp from Staphylococcus aureus reveal the ligand binding mechanism with Fibrinogen a

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Protein & Cell 2015年第10期6卷 757-766页

作者： Xinyue Zhang Meng Wu Wei Zhuo JinkeGu Sensen Zhang Jingpeng Ge Maojun Yang Key Laboratory for Protein sciences of Ministry of Education Tsinghua-Peking Center for Life Sciences School of Life Sciences Tsinghua University Beijing 100084 China

Bone sialoprotein-binding protein （Bbp）, a MSCRAMMs （Microbial Surface Components Recognizing Adhesive Matrix Molecules） family protein expressed on the surface of Staphylococcus aureus （S. aureus）, mediates adherence to fibrinogen a （Fg a）, a component in the extracellular matrix of the host cell and is important for infection and pathogenesis. In this study, we solved the crystal structures of apo-Bbp273-598 and Bbp273-598-Fg a561-575 complex at a resolution of 2.03 A and 1.45 A, respectively. Apo-Bbp273-598 contained the ligand binding region N2 and N3 domains, both of which followed a DE variant IgG fold characterized by an additional DI strand in N2 domain and D1＇ and D2＇ strands in N3 domain. The peptide mapped to the Fg o561-575 bond to Bbp273-sgs on the open groove between the N2 and N3 domains. Strikingly, the disordered C-terminus in the apo-form reorganized into a highly-ordered loop and a β-strand G＂ covering the ligand upon ligand binding. BbpAla298-Gly301 in the N2 domain of the Bbp273-598-Fg a561-575 complex, which is a loop in the apo-form, formed a short a-helix to interact tightly with the peptide. In addition, Bbpser547-Glns61 in the N3 domain moved toward the binding groove to make contact directly with the peptide, while BbpAsp338-Gly355 and BbpThr365-Tyr387 in N2 domain shifted their configurations to stabilize the reorganized C-terminus mainly through strong hydrogen bonds. Altogether, our results revealed the molecular basis for Bbp-ligand interaction and advanced our understanding of S. aureus infection process.

关键词： bone sialoprotein-binding protein (Bbp),fibrinogen serine-aspartate repeat (Sdr) Microbial SurfaceComponents Recognizing Adhesive Matrix Molecules(MSCRAMM) Staphylococcus aureus

Insights from a proteomic atlas of human Alzheimer's disease brain tissue

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Neural Regeneration Research 2025年第3期20卷 799-800页

作者： Tomas Kavanagh Eleanor Drummond Brain and Mind Centre and School of Medical sciences University of SydneyCamperdownNSWAustralia

There is an urgent need to identify new drug targets for Alzheimer's disease(AD). While new immunotherapies show promise, clinical benefit appears low, and side effects are high. A greater understanding of the disease mechanisms driving AD is an essential factor that will facilitate the identification of new, effective drug targets.

关键词： Alzheimer clinical driving