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Boosting thermal stability and crystallization of closed-loop-recyclable biodegradable poly(p-dioxanone) by end-group regulation

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Science China Chemistry 2024年第2期67卷 642-651页

作者： Jin Lei Zhu-Xin gui Wan-ting Xiong Gang Wu Si-Chong Chen Yu-Zhong Wang The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials(MoE) National Engineering Laboratory of Eco-Friendly Polymeric Materials(Sichuan)State Key Laboratory of Polymer Materials EngineeringCollege of ChemistrySichuan UniversityChengdu610064China

A chemically closed-loop-recyclable biodegradable polymer,poly(p-dioxanone)(PPDO),is one of the ideal candidates for single-use plastic products due to its suitability for different application ***,when PPDO wastes can be collected,its monomer p-dioxanone(PDO) will be obtained through chemical recycling of these wastes;when cannot be collected,the wastes are able to be biodegraded into harmless ***,unsatisfied thermal stability and low crystallization rate of PPDO restrict its wider ***,based on end-group regulation,we simultaneously realized the significant enhancement of thermal stability and crystallization of PPDO through the simple melt processing with tributyl phosphite(TBP) or triphenyl phosphite(TPP).The model reactions were conducted to investigate the reaction mechanism and theoretical products during the preparation of PPDO/phosphite *** kinds of phosphites were proved to act as the end-capped reagent and chain extender in the melt processing,while TBP presented better *** a result,the activation energy of thermal decomposition was largely elevated,and the unprecedented T_(5%)(the temperature at a weight loss of 5%) and Tmax(the temperature at a maximum rate of weight loss) of PPDO were obtained,i.e.,T_(5%)of ~330 ℃ and Tmaxof ~385 ℃ in N_(2) atmosphere,T_(5%)of ~240 ℃ and Tmaxof ~317 ℃ in air atmosphere,***,the increased crystallization rate,crystallinity,crystalline orderliness,and realizable monomer recovery(yield >90%,purity >99.9%) of PPDO/phosphite compounds were confirmed.

关键词： poly(p-dioxanone) phosphite thermal stability crystallization end-group regulation

Differential expression of VASA gene in ejaculated spermatozoa from normozoospermic men and patients with oligozoospermia

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Asian Journal of Andrology 2007年第3期9卷 339-344页

作者： Xin Guo yao-ting gui Ai-Fa Tang Li-Hua Lu Xin Gao Zhi-Ming Cai The Laboratory of Male Reproductive Medicine Peking University Shenzhen Hospital Shenzhen 518036 China Department of Urosurgery The Third Affiliated Hospital Sun Yet-Sen University Guangzhou 510630 China

Aim： To detect the expression of VASA in human ejaculated spermatozoa, and to compare the expression of VASA between normozoospermic men and patients with oligozoospermia. Methods： Ejaculated spermatozoa were collected from normozoospermic men and patients with oligozoospermia by masturbation, and subsequently segregated through a discontinuous gradient of Percoll to obtain the spermatozoa. Reverse transcription polymerase chain reaction （RT- PCR）, quantitative RT-PCR （QRT-PCR）, immunoflurescence and Western blotting were used to detect the expression of VASA in mRNA and protein levels. Results： VASA mRNA was expressed in the ejaculated spermatozoa. QRT-PCR analysis showed that VASA mRNA level was approximately 5-fold higher in normozoospermic men than that in oligozoospermic men. Immunofluorescence and Western blotting analysis showed that VASA protein was located on the cytoplasmic membrane of heads and tails of spermatozoa, and its expression was significantly decreased in oligozoospermic men, which is similar to the result of QRT-PCR. Conclusion： The expression of VASA mRNA and protein was significantly decreased in the sperm of oligozoospermic men, which suggested the lower expression of the VASA gene might be associated with pathogenesis in some subtypes of male infertility and VASA could be used as a molecular marker for the diagnosis of male infertility.

关键词： VASA ejaculated spermatozoa oligozoospermia male infertility spermatogenesis

Possible bias of the constraints on the Hubble constant owing to the quasi-Gaussian distribution of DM_(IGM)in fast radio bursts

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Chinese Physics C 2024年第7期48卷 211-220页

作者：陈贵垚李昕 Department of Physics Chongqing UniversityChongqing 401331China Chongqing Key Laboratory for Strongly Coupled Physics Chongqing UniversityChongqing 401331China

Fast radio bursts(FRBs)are useful cosmological probes with numerous applications in *** distribution of the dispersion measurement contribution from the intergalactic medium is a key issue.A quasi-Gaussian distribution has been used to replace the traditional Gaussian distribution,yielding promising ***,this study suggests that there may be additional challenges in its *** used 35 well-localized FRBs to constrain the Hubble constant H_(0)along with two FRB-related parameters,yielding H_(0)=■The best-fitting Hubble constant H_(0)is smaller than the value obtained from the Cosmic Microwave Background(CMB),which may be caused by the small sample size of current FRB *** Carlo simulations indicate that a set of 100 simulated FRBs provides a more precise fitting result for the Hubble ***,the precision of the Hubble constant does not improve when further enlarging the FRB *** simulations reveal a systematic deviation in the fitting results of■,attributed to the quasi-Gaussian distribution of the dispersion measure in the intergalactic *** this,the results remain reliable within 1σuncertainty,assuming that a sufficient number of FRB data points are available.

关键词： fast radio bursts Hubble constant cosmological parameters

Plasmonic quantum dots modulated nano-mineral toward photothermal reduction of CO_(2)coupled with biomass conversion

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Nano Research 2024年第6期17卷 5061-5072页

作者： Guangbiao Cao Haoran Xing Haoguan gui Chao yao Yinjuan Chen Yongsheng Chen Xiazhang Li National-local Joint Engineering Research Center of Biomass Refining and High-quality Utilization Changzhou UniversityChangzhou 213164China School of Civil and Environmental Engineering Georgia Institute of TechnologyAtlantaGA 30332-0373USA

Simultaneous conversion of CO_(2)and biomass into value-added chemicals through solar-driven catalysis holds tremendous importance for fostering a sustainable circular ***,plasmonic Bi quantum dots were immobilized on phosphoric acid modified attapulgite(P-ATP)nanorod using an in-situ reduction-deposition method,and were employed for photocatalytic reduction of CO_(2)coupled with oxidation of biomass-derived benzyl *** revealed that Bi atoms successfully integrated into the basal structure of P-ATP,forming chemically coordinated Bi-O-Si bonds that served as efficient transportation channels for *** incorporation of high-density monodispersed Bi quantum dots induced a surface plasmon resonance(SPR)effect,expanding the light absorption range into the near-infrared *** a consequence,the photo-thermal transformation was significantly accelerated,leading to enhanced reaction ***,50%Bi/P-ATP nanocomposite exhibited the highest plasmon-mediated photocatalytic CH4 generation(115.7μmol·g^(−1)·h^(−1))and CO generation(44.9μmol·g^(−1)·h^(−1)),along with remarkable benzaldehyde generation rate of 79.5μmol·g^(−1)·h^(−1)in the photo-redox coupling system under solar light *** hydrogen protons released from the oxidation of benzyl alcohol facilitated the incorporation of more hydrogen protons into CO_(2)to form key CH_(3)O−*** work demonstrates the synergistic solar-driven valorization of CO_(2)and biomass using natural mineral based catalyst.

关键词： photothermal catalysis clay mineral plasmon CO_(2)reduction biomass conversion

Mutual antagonism of mouse-adaptation mutations in HA and PA proteins on H9N2 virus replication

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Virologica Sinica 2024年第1期39卷 56-70页

作者： Liping Ma Huabin Zheng Xianliang Ke Rui gui Zhongzi yao Jiasong Xiong Quanjiao Chen CAS Key Laboratory of Special Pathogens and Biosafety Wuhan Institute of VirologyChinese Academy of SciencesWuhan430207China Center for Biosafety Mega-Science Wuhan Institute of VirologyChinese Academy of SciencesWuhan430207China Hubei Jiangxia Laboratory Wuhan430207China University of Chinese Academy of Sciences Beijing100049China

Avian H9N2 viruses have wide host range among the influenza A ***,knowledge of H9N2 mammalian adaptation is *** explore the molecular basis of the adaptation to mammals,we performed serial lung passaging of the H9N2 strain A/chicken/Hunan/8.27 YYGK3W3-OC/2018(3W3)in mice and identified six mutations in the hemagglutinin(HA)and polymerase acidic(PA)*** L226Q,T511I,and A528V of HA were responsible for enhanced pathogenicity and viral replication in mice;notably,HA-L226Q was the key *** T97I,I545V,and S594G of PA contributed to enhanced polymerase activity in mammalian cells and increased viral replication levels in vitro and in ***-T97I increased viral polymerase activity by accelerating the viral polymerase complex *** findings revealed that the viral replication was affected by the presence of PA-97I and/or PA-545V in combination with a triple-point HA ***,the double-and triple-point PA mutations demonstrated antagonistic effect on viral replication when combined with ***,any combination of PA mutations,along with double-point HA mutations,resulted in antagonistic effect on viral *** also observed antagonism in viral replication between PA-545V and PA-97I,as well as between HA-528V and *** findings demonstrated that several antagonistic mutations in HA and PA proteins affect viral replication,which may contribute to the H9N2 virus adaptation to mice and mammalian *** findings can potentially contribute to the monitoring of H9N2 field strains for assessing their potential risk in mammals.

关键词： Influenza Avirus(IAV) H9N2 HA PA Antagonism Mouse adaptation

Clinical outcomes in patients with stage non-seminomatous germ cell cancer

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Asian Journal of Andrology 2013年第4期15卷 558-563,I0011页

作者： Zhao-Jie Lv Song Wu Pei Dong Kai yao Yin-Yin He yao-ting gui Fang-Jian Zhou Zhuo-Wei Liu Zhi-Ming Cai Shenzhen Second People's Hospital the First Affiliated Hospital of Shenzhen University Shenzhen 518036 China LAnhui Medical University Hefei 230032 China Department of Urology Sun Yat-Sen University Cancer Centre Guangzhou 510060 China Institute of Immunology Zhongshan School of Medicine Sun Yat-Sen University Guangzhou 510060 China and Institute of Urology Shenzhen PKU-HKUST Medical Centre Shenzhen 518036 China

This study assesses the long-term outcomes in Han Chinese patients with clinical stage I non-seminomatous germ cell testicular cancer （CSI NSGCT） treated with surveillance, retroperitoneal lymph node dissection （RPLND） and adjuvant chemotherapy. We retrospectively evaluated 89 patients with a mean age of 26.5 years. After orchiectomy, 37 patients were treated with surveillance, 34 underwent RPLND and 18 were managed with chemotherapy. The overall survival rate, the recurrence-free survival rate and the risk factors were evaluated. The median follow-up length was 92 months （range： 6-149 months）. Thirteen of the 89 patients （14.6%） had relapses, and one died by the evaluation date. The overall survival rate was 98.9%. The cumulative 4-year recurrence-free rates were 80.2%, 92.0% and 100% for the surveillance, RPLND and chemotherapy groups, respectively. The disease-free period tended to be briefer in patients with a history of cryptorchidism and those with stage Is. Therefore, surveillance, RPLND and adjuvant chemotherapy might be reliable strategies in compliant patients with CSI NSGCT. Surveillance should be recommended for patients with the lowest recurrence rate, especially those without lymphovascular invasion. This study might aid the establishment of a standard therapy for CSI NSGCT in China.

关键词： chemotherapy clinical stage I non-seminomatous germ cell testicular cancer (CSI NSGCT) outcome retroperitoneallymph node dissection (RPLND) surveillance treatment protocols

Artificial Water Channel Promoting Depolymerization of Actin Filaments to Trigger Cancer Cell Apoptosis

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Chinese Journal of Chemistry 2024年第12期42卷 1335-1340页

作者： Lei Zhang Yin-gui Cao ting Fan Jjiatong Zhao Yong-Hong Fu Qi Xiao Zhan-ting Li Yunfeng Wang Bo Xiao Jun-Li Hou Department of Chemistry Fudan University220 Handan RoadShanghai 200433China State Key Laboratory of Silkworm Genome Biology Cllege of SericultureTextileand Biomass Sciences InstitutionSouthwest UniversityChongqing400715China ENT Institute and Otorhinolaryngology Department of Eye&ENT Hospital Fudan UniversityShanghai 200031 Fudan International School 325 Guoquan RoadShanghai 200433China

Actin filaments play important physiological functions,which have become potential targets of antitumor *** chemicals to intervene their polymerization-depolymerization dynamics would generate new strategies for designing antitumor *** this report,an artificial water channel appending acetazolamide moiety,a ligand that can selectively bind to carbonic anhydrase IX,has been prepared.

关键词： Artificial water channel Actin depolymerization Cell apoptosis Nanostructures Molecular recognition Supramolecular chemistry

dentification of testosterone-/androgen receptor-regulated genes in mouse Sertoli cells

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Asian Journal of Andrology 2012年第2期14卷 294-300页

作者： Qiao-Xia Zhang Xiao-Yan Zhang Zhen-Ming Zhang Wei Lu Ling Liu Gang Li Zhi-Ming Cai yao-ting gui Chawnshang Chang The Guangdong and Shenzhen Key Lab of Male Reproductive Medicine and Genetics Sex Hormone Research CenterPeking University Shenzhen HospitalShenzhen PKU-HKUST Medical CenterShenzhen 518036China Department of Biochemistry and Molecular Biology Peking University Health Science CenterPeking UniversityBeijing 100083China George H.Whipple Lab for Cancer Research Departments of Pathology and UrologyUniversity of Rochester Medical CenterRochester NY 14642USA Sex hormone Research Center China Medical UniversityTaichung 404TaiwanChina

Androgen and androgen receptor （AR） play important roles in male spermatogenesis and fertility, yet detailed androgen/AR signals in Sertoli cells remain unclear. To identify AR target genes in Sertoli cells, we analyzed the gene expression profiles of testis between mice lacking AR in Sertoli cells （S-AR-/y） and their littermate wild-type （WT） mice. Digital gene expression analysis identified 2276 genes downregulated and 2865 genes upregulated in the S-AR-/y mice testis compared to WT ones. To further nail down the difference within Sertoli cells, we first constructed Sertoli cell line TM4 with stably transfected AR （named as TM4/AR） and found androgens failed to transactivate AR in Sertoli TM4 and TM4/AR cells. Interestingly, additional transient transfection of AR-cDNA resulted in significant androgen responsiveness with TM4/AR cells showing 10 times more androgen sensitivity than TM4 cells. In the condition where maximal androgen response was demonstrated, we then analyzed gene expression and found the expression levels of 2313 genes were changed more than twofold by transient transfection of AR-cDNA in the presence of testosterone. Among these genes, 603 androgen-/ AR-regulated genes, including 164 upregulated and 439 downregulated, were found in both S-AR-/y mice testis and TM4/AR cells. Using informatics analysis, the gene ontology was applied to analyze these androgen-/AR-regulated genes to predict the potential roles of androgen/AR in the process of spermatogenesis. Together, using gene analysis in both S-AR-/y mice testis and TM4/AR cells may help us to better understand the androeen/AR signals in Sertoli cells and their influences in spermatogenesis.

关键词： androgen receptor conditional knockout mice Sertoli cells testis TM4 cells

Cloning and Character Analysis of A Novel Testis-specific Gene,TSF22,in Mice

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Journal of Reproduction and Contraception 2007年第1期18卷 11-18页

作者： Ai-fa TANG Zhen-dong YU yao-ting gui Xin GUO Xin GAO Zhi-ming CAI Urinary Surgery Thrid Affiliated Hospital of Sun Yat-Sen University Guangzhou 510630 China Shenzhen Key Laboratory of Male Reproduction and Genetics Shenzhen hospital of Peking University Shenzhen PKU-HKUST Medical Center Shenzhen 518036 China

Objective To identify genes that involved in spermatogenesis. Methods In order to screen the testis-specific genes, testes cDNA samples from BALB/c mice of different postnatal days （days 4, 9, 18, 35, 54 and 6 months） were performed with mouse whole genome Affymetrix chip. The characteristics of the selected gene were analyzed by various bioinformatic tools. The expression profile of the selected gene was identified by RT-PCR. Results By analyzing the hybridization signals, a gene with a differential expression in the developmental stages of testis was identified. This gene was designated as TSF22. The full length cDNA of 1 597 bp contained an open reading frame of 570 bp which encoded a putative protein of 190 amino acids and a molecular weight of 22.106 kD. RT-PCR analysis revealed that TSF22 mRNA was exclusively expressed in mice testis. Conclusions TSF22, functions as a testis-specific transcription factor, may play important roles during spermatogenesis.

关键词： gene chip TSF22 gene spermatogenesis