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51.
The precise physiological causes that result in reduced development of oocytes after heat shock (HS) are not clear. In this study, apoptosis, heat shock protein70 (hsp70), and in vitro development of porcine oocytes were evaluated after HS. Porcine cumulus-oocyte complexes (COCs) were subjected to in vitro maturation for 42 h. The matured oocytes were then heated at 41.5 degrees C for 0 h (control, C0h), 1 h (HS1h), 2 h (HS2h), or 4 h (HS4h). An additional group of oocytes was cultured for 4 h without HS (control, C4h). In Experiment 1, expression of hsp70 was detected by Western-blotting and no difference between controls and HS groups was observed. In Experiment 2, apoptosis of matured oocytes after HS was examined by Annexin V-FITC and TUNEL. No significant TUNEL-positive signals were detected in the heated oocytes compared to the controls, but the intensity of Annexin V-FITC labeling among different groups increased with length of HS and in vitro culture (P<0.05). Oocytes were parthenogenetically activated by an electric pulse plus 6-DMAP (Experiment 3). Mean (+/-S.E.M.) embryonic development in HS2h (cleavage: 42+/-29%; blastocyst: 11+/-10%) and HS4h (cleavage: 36+/-28%; blastocyst: 11+/-8%) were decreased when compared to those in C0h (cleavage: 63+/-12%; blastocyst: 24+/-14%) and C4h (cleavage: 66+/-8%; blastocyst: 21+/-11%). Numbers of blastocysts with TUNEL-positive signals were similar among groups, but the signals increased before the eight-cell stage in HS groups (P<0.05). In conclusion, developmental competence of matured pig oocytes was compromised after heat shock, but it was not closely associated with the expression of oocyte hsp70. However, there may be a link between apoptosis and developmental competence of porcine oocytes. 相似文献
52.
Park SH Kim CM Je BI Park SH Park SJ Piao HL Xuan YH Choe MS Satoh K Kikuchi S Lee KH Cha YS Ahn BO Ji HS Yun DW Lee MC Suh SC Eun MY Han CD 《Planta》2007,227(1):1-12
OSH6 (Oryza sativa Homeobox6) is an ortholog of lg3 (Liguleless3) in maize. We generated a novel allele, termed OSH6-Ds, by inserting a defective Ds element into the third exon of OSH6, which resulted in a truncated OSH6 mRNA. The truncated mRNA was expressed ectopically in leaf tissues and encoded the N-terminal region of OSH6, which includes
the KNOX1 and partial KNOX2 subdomains. This recessive mutant showed outgrowth of bracts or produced leaves at the basal node
of the panicle. These phenotypes distinguished it from the OSH6 transgene whose ectopic expression led to a “blade to sheath transformation” phenotype at the midrib region of leaves, similar
to that seen in dominant Lg3 mutants. Expression of a similar truncated OSH6 cDNA from the 35S promoter (35S::ΔOSH6) confirmed that the ectopic expression of this product was responsible for the aberrant bract development. These data suggest
that OSH6-Ds interferes with a developmental mechanism involved in bract differentiation, especially at the basal nodes of panicles.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
53.
Geon Ha Kim Seun Jeon Kiho Im Hunki Kwon Byung Hwa Lee Ga Young Kim Hana Jeong Noh Eul Han Sang Won Seo Hanna Cho Young Noh Sang Eon Park Hojeong Kim Jung Won Hwang Cindy W. Yoon Hee Jin Kim Byoung Seok Ye Ju Hee Chin Jung-Hyun Kim Mee Kyung Suh Jong Min Lee Sung Tae Kim Mun-Taek Choi Mun Sang Kim Kenneth M Heilman Jee Hyang Jeong Duk L. Na 《PloS one》2015,10(4)
The purpose of this study was to investigate if multi-domain cognitive training, especially robot-assisted training, alters cortical thickness in the brains of elderly participants. A controlled trial was conducted with 85 volunteers without cognitive impairment who were 60 years old or older. Participants were first randomized into two groups. One group consisted of 48 participants who would receive cognitive training and 37 who would not receive training. The cognitive training group was randomly divided into two groups, 24 who received traditional cognitive training and 24 who received robot-assisted cognitive training. The training for both groups consisted of daily 90-min-session, five days a week for a total of 12 weeks. The primary outcome was the changes in cortical thickness. When compared to the control group, both groups who underwent cognitive training demonstrated attenuation of age related cortical thinning in the frontotemporal association cortices. When the robot and the traditional interventions were directly compared, the robot group showed less cortical thinning in the anterior cingulate cortices. Our results suggest that cognitive training can mitigate age-associated structural brain changes in the elderly.
Trial Registration
ClnicalTrials.gov NCT01596205 相似文献54.
对东北地区不同环境要素Se的分布与转化规律的研究表明,基岩、土壤、粮食和动物毛Se含量分别为0.12、0.150-0.540、0.0096-0.0765和0.0405-0.1414μg.g^-1;城市和农村儿童发Se含量为0.460和0.182μg.g^-1。根据不同要素Se含量和生态效应,可将该区分为Se适宜区、缺乏区和过渡区3个1级区,每个1级区又分为高Se源区的低Se源区。 相似文献
55.
Xian Zeng Hui Zhao Yubin Li Jiajun Fan Yun Sun Shaofei Wang Ziyu Wang Ping Song Dianwen Ju 《Autophagy》2015,11(2):355-372
The frontline tyrosine kinase inhibitor (TKI) imatinib has revolutionized the treatment of patients with chronic myeloid leukemia (CML). However, drug resistance is the major clinical challenge in the treatment of CML. The Hedgehog (Hh) signaling pathway and autophagy are both related to tumorigenesis, cancer therapy, and drug resistance. This study was conducted to explore whether the Hh pathway could regulate autophagy in CML cells and whether simultaneously regulating the Hh pathway and autophagy could induce cell death of drug-sensitive or -resistant BCR-ABL+ CML cells. Our results indicated that pharmacological or genetic inhibition of Hh pathway could markedly induce autophagy in BCR-ABL+ CML cells. Autophagic inhibitors or ATG5 and ATG7 silencing could significantly enhance CML cell death induced by Hh pathway suppression. Based on the above findings, our study demonstrated that simultaneously inhibiting the Hh pathway and autophagy could markedly reduce cell viability and induce apoptosis of imatinib-sensitive or -resistant BCR-ABL+ cells. Moreover, this combination had little cytotoxicity in human peripheral blood mononuclear cells (PBMCs). Furthermore, this combined strategy was related to PARP cleavage, CASP3 and CASP9 cleavage, and inhibition of the BCR-ABL oncoprotein. In conclusion, this study indicated that simultaneously inhibiting the Hh pathway and autophagy could potently kill imatinib-sensitive or -resistant BCR-ABL+ cells, providing a novel concept that simultaneously inhibiting the Hh pathway and autophagy might be a potent new strategy to overcome CML drug resistance. 相似文献
56.
Histamine produced concentration-dependent contractions in cat duodenal smooth muscle cells that were obtained by enzymatic digestion of smooth muscle with collagenase F. Pyrilamine, an H1 receptor antagonist, inhibited the contractile response while famotidine, an H2 receptor antagonist, augmented it. In cells with selectively preserved H1 receptors, produced by pretreatment with pyrilamine followed by inactivation of all unprotected receptors with N-ethylmaleimide, histamine-induced contraction was significantly augmented as compared with control cells. Pertussis toxin (PTX) had no effect on contraction, suggesting that the H1 receptor is coupled to a PTX-insensitive G protein. Gi2, Gi3, Go, Gs, and Gq subunits were present in cat duodenum, and histamine-induced contraction was inhibited by Gq antibody after cell permeabilization. Neomycin, a PLC inhibitor, inhibited the histamine-induced cell contraction, but not rhoCMB, a PLD inhibitor, or DEDA, a PLA2 inhibitor. Heparin, an IP3 receptor inhibitor, inhibited contraction whereas chelerythrine, a PKC inhibitor, had no effect. We conclude that histamine-induced contraction in cat duodenal smooth muscle cells is mediated by H1 receptors coupled to a PTX-insensitive Gq protein and results in activation of phosphatidylinositol-specific phospholipase C (PI-PLC). 相似文献
57.
植酸对稻米品质影响的研究(Ⅰ) 总被引:2,自引:0,他引:2
本文报道在水稻生长的抽穗期、齐穗期、灌浆期和蜡熟期喷施不同浓度植酸改良稻米品质的研究。结果表明,在水稻生长的不同阶段,控制喷施植酸浓度可提高糙米率,降低稻米垩白。 相似文献
58.
Kim BJ Lee H 《Biology of the cell / under the auspices of the European Cell Biology Organization》2008,100(12):675-686
Background information. PCNA (proliferating cell nuclear antigen) is required for a wide range of cellular functions, including DNA replication and damage repair. To be functional, PCNA must associate with the replication and repair foci. In addition, PCNA also mediates targeting of certain replication and repair proteins to these foci. However, the mechanism is not yet known by which PCNA is imported into the nucleus, and then localized to the replication and repair foci. Results. We have found that an NLS (nuclear localization sequence) is present within the amino acid 101–120 segment of PCNA. An NLS‐deleted PCNA was localized in the cytoplasm and showed 5‐fold lower affinity for importin‐β than wild‐type, suggesting that PCNA may be imported into the nucleus by importin‐β via its NLS. We previously reported that the functional unit of PCNA is a double trimer (as opposed to single homotrimer), and Lys‐110 is essential for the formation of the double trimer complex [Naryzhny, Zhao and Lee ( 2005 ) J. Biol. Chem. 280 , 13888–13894]. The present study shows that the substitution of Lys‐110 within the NLS to an alanine residue did not affect its nuclear localization. However, the double‐trimer‐defective PCNA(K110A) was not localized at replication or repair foci. In contrast, the double‐trimer‐intact PCNA(K117A) mutant was targeted normally to replication and repair foci. Interestingly, in cells transfected with PCNA(K110A), but not PCNA(K117A), caspase‐3‐mediated chromosome fragmentation was activated. Conclusions. The present study suggests that the regulation of PCNA is intimately connected with that of DNA replication, repair and cell death signals, and raises the possibility that defects in the formation of the PCNA double‐trimer complex can cause apoptosis. 相似文献
59.
Song WY Sohn EJ Martinoia E Lee YJ Yang YY Jasinski M Forestier C Hwang I Lee Y 《Nature biotechnology》2003,21(8):914-919
We have studied the utility of the yeast protein YCF1, which detoxifies cadmium by transporting it into vacuoles, for the remediation of lead and cadmium contamination. We found that the yeast YCF1-deletion mutant DTY167 was hypersensitive to Pb(II) as compared with wild-type yeast. DTY167 cells overexpressing YCF1 were more resistant to Pb(II) and Cd(II) than were wild-type cells, and accumulated more lead and cadmium. Analysis of transgenic Arabidopsis thaliana plants overexpressing YCF1 showed that YCF1 is functionally active and that the plants have enhanced tolerance of Pb(II) and Cd(II) and accumulated greater amounts of these metals. These results suggest that transgenic plants expressing YCF1 may be useful for phytoremediation of lead and cadmium. 相似文献
60.
悬铃木方翅网蝽: 一种正在迅速扩张的城市外来入侵害虫 总被引:5,自引:0,他引:5
悬铃木方翅网蝽(Corythucha ciliata)是新近入侵我国城市生态系统的外来害虫, 严重危害城市行道树悬铃木(Platanus spp.), 自2002年该虫在湖南长沙首度报道以来, 已在我国11个省(直辖市)的25个城市发生, 尤其在长江流域呈现爆发态势。本文系统介绍了悬铃木方翅网蝽的生活史、生活习性、繁殖潜力等生物学特性, 以及扩散速度与方式、影响发生的主要环境因素、种群的耐寒耐热能力等生态学特性。最后, 在分析该虫的寄主及危害特点的基础上, 对其控制与管理对策进行了综述, 以为其管理提供参考。 相似文献