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991.
Qing-Qiu Mao Xiao-Ming Zhong Chun-Rong Feng Ai-Juan Pan Zhao-Yi Li Zhen Huang 《Cellular and molecular neurobiology》2010,30(7):1059-1066
Preclinical and clinical investigations have shown hippocampal neuronal atrophy and destruction were observed in patients
with depression, which could be ameliorated by the treatment with antidepressants. Therefore, neuroprotection has been proposed
to be one of the acting mechanisms of antidepressant. Paeoniflorin, a monoterpene glycoside, has been reported to display
antidepressant-like effects in animal models of behavioral despair. The present study aimed to examine the protective effect
of paeoniflorin on glutamate-induced neurotoxicity in cultured rat pheochromocytoma (PC12) cells. The results showed that
pretreatment with paeoniflorin elevated cell viability, inhibited apoptosis, decreased levels of intracellular reactive oxygen
species and malondialdehyde, and enhanced activity of superoxide dismutase in glutamate-treated PC12 cells. Pretreatment with
paeoniflorin also reversed the increased intracellular Ca2+ concentration and the reduced Calbindin-D28K mRNA level caused by glutamate in PC12 cells. The results suggest that paeoniflorin
exerts a neuroprotective effect on glutamate-induced neurotoxicity in PC12 cells, at least in part, via inhibiting oxidative
stress and Ca2+ overload. This neuroprotective effect may be one of the action pathways accounting for the in vivo antidepressant activity
of paeoniflorin. 相似文献
992.
Jinming Huang Hongmei Wang Changfa Wang Jianbin Li Qiuling Li Minghai Hou Jifeng Zhong 《Molecular biology reports》2010,37(1):477-483
Lactoferrin (Lf) is naturally produced by the mammary gland, having biological functions of antibacterial and anti-inflammatory
activities. To investigate whether the Lf gene is associated with mastitis in dairy cattle, a DNA sequencing approach was used to identify single nucleotide polymorphisms
(SNPs) in the gene. Three previously reported SNPs in the 5′ flanking region and one novel SNP in exon1 of Lf gene were identified. A total of 353 individuals from Holstein cattle populations were genotyped for their SNPs using Created
Restriction Site PCR (CRS-PCR) and PCR-RFLP methods. Twenty-two and nineteen combinations of three SNPs (g.3440T>G, g.3879_3880insG,
and g.4432T>C) and another three SNPs (g.3429G>A, g.3440T>G, g.3879_3880insG) were observed, respectively. The result of haplotype
analysis of four SNPs showed that fourteen different haplotypes were identified. Two major haplotypes (GECB and GECA) occurred with a frequency of 22.5 and 18.5% in the study population, respectively. Statistical analyses revealed no significant
association between one single SNP of Lf gene and SCS, whereas significant associations between their combined genotypes of three SNPs, haplotype and SCS. Combined
genotype EFCDBB and GGEFDD with the lowest SCS were favorable for the mastitis resistance. They may be used as a possible candidate for marker-assisted
selection in dairy cattle breeding program. 相似文献
993.
Wenyan Liu Ji Wang Qiuling Li Zhihua Ju Jinming Huang Hongmei Wang Shunde Liu Jianbin Li Jifeng Zhong Changfa Wang 《Molecular biology reports》2010,37(8):3771-3777
As an essential signaling modulator, Src gene appears to be necessary for increased expression of the prolactin receptor, normal downstream signaling, and alveolar cell organization. In this study, we detected the polymorphism of Src gene by polymerase chain reaction-restriction fragment length polymorphism assay (PCR-RFLP) and DNA sequencing methods in 985 individuals from three Chinese cattle breeds. Three novel single nucleotide polymorphisms (SNPs) (g.14062C>T ss161151834, g.17302G>A ss161151835, g.18107T>C ss161151836) were detected. Least squares analysis showed that cows with g.14062C>T-CC genotypes and g.18107T>C-TT genotypes had the highest protein rate, while the cows with g.17302G>A-GG genotype had higher 305 d milk yield (p < 0.05), fat yield (p < 0.01) and protein yield (p < 0.01) than the ones with genotypes g.17302G>A-GA. These results revealed the statistical significant effects of three SNPs of the Src gene on the milk production traits in Chinese Holstein. In addition, based on the nine genotypes constructed from 27 combined haplotypes, the association analysis between combined haplotypes and milk production traits was carried out. Statistic results showed that the cows with combined haplotypes H2H4(CCGATT) had the highest fat rate and the highest protein rate and the cows with combined haplotypes H1H8(TCGATC) and H3H7(TCGGCC) had greater 305 d mild yield than H1H2(CCAATC)(P < 0.05). Our finding demonstrated that the Src gene possibly contributed to conducting association analysis and can be recognized as genetic marker in milk production traits and other performance for animal breeding and genetics. 相似文献
994.
Xi-Mei Zhang Qiu-Ming Li Dong-Ju Su Ning Wang Zhi-Yan Shan Lian-Hong Jin Lei Lei 《Molecular biology reports》2010,37(3):1197-1202
Recently, differentiated somatic cells had been reprogrammed to pluripotential state in vitro, and various tissue cells had
been elicited from those cells. Epigenetic modifications allow differentiated cells to perpetuate the molecular memory needed
for the cells to retain their identity. DNA methylation and histone deacetylation are important patterns involved in epigenetic
modification, which take critical roles in regulating DNA expression. In this study, we dedifferentiated NIH/3T3 fibroblasts
by 5-aza-2-deoxycytidine (5-aza-dC) and Trichstatin A (TSA) combination, and detected gene expression pattern, DNA methylation
level, and differentiation potential of reprogrammed cells. As the results, embryonic marker Sox2, klf4, c-Myc and Oct4 were
expressed in reprogrammed NIH/3T3 fibroblasts. Total DNA methylation level was significant decreased after the treatment.
Moreover, exposure of the reprogrammed cells to all trans-retinoic acid (RA) medium elicited the generation of neuronal class
IIIβ-tubulin-positive, neuron-specific enolase (NSE)-positive, nestin-positive, and neurofilament light chain (NF-L)-positive
neural-like cells. 相似文献
995.
Liping Yang Ning Liu Xiang Hu Wenfeng Zhang Tao Wang Hong Li Bo Zhang Shuanglin Xiang Jianlin Zhou Jian Zhang 《Molecular biology reports》2010,37(6):2967-2973
TNFAIP1 is a protein which can be induced by tumor necrosis factorα (TNFα) and interleukin-6 (IL-6), it may play roles in
DNA synthesis, DNA repair, cell apoptosis and human diseases. However, very little has been known about how TNFAIP1 acts in
these physiological processes. In this paper, CK2β was identified as a partner of TNFAIP1 by screening the HeLa cDNA library
in yeast two-hybrid system with TNFAIP1 as a bait. Furthermore, it was demonstrated that CK2 could phosphorylate TNFAIP1 in vitro
and in vivo, which facilitated the distribution of TNFAIP1 in nucleus and enhanced its interaction with PCNA. It is suggested
that the phosphorylation of TNFAIP1 may be required for its functions. 相似文献
996.
Adak AK Leonov AP Ding N Thundimadathil J Kularatne S Low PS Wei A 《Bioconjugate chemistry》2010,21(11):2065-2075
Bishydrazides are versatile linkers for attaching glycans to substrates for lectin binding and pathogen detection schemes. The α,ω-bishydrazides of carboxymethylated hexa(ethylene glycol) (4) can be conjugated at one end to unprotected oligosaccharides, then attached onto carrier proteins, tethered onto activated carboxyl-terminated surfaces, or functionalized with a photoactive cross-linking agent for lithographic patterning. Glycoconjugates of bishydrazide 4 can also be converted into dithiocarbamates (DTCs) by treatment with CS(2) under mild conditions, for attachment onto gold substrates. The immobilized glycans serve as recognition elements for cell-surface lectins and enable the detection and capture of bacterial pathogens such as Pseudomonas aeruginosa by their adsorption onto micropatterned substrates. A detection limit of 103 cfu/mL is demonstrated, using a recently introduced method based on optical pattern recognition. 相似文献
997.
Zhang N Liang J Tian Y Yuan L Wu L Miao S Zong S Wang L 《Molecular biology of the cell》2010,21(24):4312-4324
Most Rho family GTPases serve as key molecular switches in a wide spectrum of biological processes. An increasing number of studies have expanded their roles to the spermatogenesis. Several members of Rho family have been confirmed to be essential for mammalian spermatogenesis, but the precise roles of this family in male reproduction have not been well studied yet. Here we report a surprising function of an atypical and testis-specific Rho GTPase, RSA-14-44 in spermatogenesis. Featured by unique structural and expressional patterns, RSA-14-44 is distinguished from three canonical members of Rho cluster. Thus, we define RSA-14-44 as a new member of Rho GTPases family and rename it RhoS (Rho in spermatogenic cells). RhoS associates with PSMB5, a catalytic subunit of the proteasome, in a series of stage-specific spermatogenic cells. More importantly, RhoS does not directly modulate the cellular proteasome activity, but participates in regulating the stability of "unincorporated" PSMB5 precursors. Meanwhile, our data demonstrate that the activation of RhoS is prerequisite for negatively regulating the stability of PSMB5 precursors. Therefore, our finding uncovers a direct and functional connection between the Rho GTPase family and the pathway of proteasome biogenesis and provide new clues for deciphering the secrets of spermatogenesis. 相似文献
998.
Linkage and association studies suggested the relationship between a-adducin polymorphism (Gly460Trp; rs4961) and genetic
susceptibility to salt-sensitivity. However, the currently available results were inconsistent. This study aimed to define
quantitatively the association between salt-sensitivity and α-adducin Gly460Trp polymorphism in all published case-control
studies. Publications from PubMed and other databases were retrieved. The major inclusion criteria were: (1) case-control
design; (2) salt-sensitivity confirmed by sodium loading tests, and (3) the distribution of genotypes given in detail. Seven
case-control studies fulfilled the inclusion criteria. In total they involved 820 subjects (454 salt-sensitive and 366 non-salt-sensitive).
The meta-analysis shows that Gly460Trp polymorphism in general is not significantly associated with salt-sensitivity [OR (95%CI):
1.40 (0.96, 2.04),P = 0.08]. Subgroup analysis showed that the association is statistically significant in Asian people [OR (95%CI):1.33 (1.06,
1.69),P = 0.02] but not in Caucasian people [OR (95%CI):1.98 (0.57, 6.92),P = 0.28]. This indicates that blood pressure response to sodium varies between ethnical groups. More studies based on a larger
population are required to evaluate further the role of a-adducin Gly460Trp polymorphism in salt-sensitive hypertension. 相似文献
999.
Yan Liu Guihua Gong Liping Xie Ning Yuan Chunbao Zhu Baoquan Zhu Youjia Hu 《Molecular biotechnology》2010,44(2):101-109
Cephalosporins are widely used as anti-infectious β-lactam antibiotics in clinic. For the purpose of increasing the yield
of cephalosporin C (CPC) fermentation, especially in an industrial strain, A. chrysogenum genes cefEF and cefG, which encode the ultimate and penultimate steps in CPC biosynthesis, cefT, which encodes a CPC efflux pump, and vgb, which encodes a bacterial hemoglobin gene were transformed in various combinations into an industrial strain of A. chrysogenum. Both PCR and Southern blotting indicated that the introduced genes were integrated into the chromosome of A. chrysogenum. Carbon monoxide difference spectrum absorbance assay was performed and the result showed that Vitreoscilla hemoglobin was successfully expressed in A. chrysogenum and had biological activity. HPLC analysis of fermentation broth of recombinant A. chrysogenum showed that most transformants had a higher CPC production level than the parental strain. Multiple transformants containing
an additional copy of cefG showed a significant increase in CPC production. However, cefT showed little effect on CPC production in this high producer. The highest improvement of CPC titer was observed in the mutant
with an extra copy of cefG + cefEF + vgb whose CPC production was increased by 116.3%. This was the first report that three or more genes were introduced simultaneously
into A. chrysogenum. Our results also demonstrated that the combination of these genes had a synergy effect in a CPC high producer. 相似文献
1000.