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991.
Fuli Wang Umer Farooq Awan Yuanyuan Wang Luna Wang Hong Qing Hong Ma Yulin Deng 《International journal of molecular sciences》2014,15(6):10738-10750
The adaptive immune system has implications in pathology of Parkinson’s disease (PD). Research data demonstrated that the peripheral CD4+ T-cell population decreased in pathogenesis of PD. The effect of damaged dopaminergic neurons on peripheral T cells of PD is still unknown. In this study, we constructed a neuronal and glial cells co-culture model by using human neuroblastoma cells SH-SY5Y and gliomas cells U87. After the co-culture cells were treated with neurotoxin 1-methyl-4-phenylpyridinium (MPP+) for 24 h, the conditioned media was harvested and used to cultivate T-cell leukemia Jurkat cells for another 24 h. We then analyzed the cell proliferation, cell cycle and necrosis effect of Jurkat cells. The results showed that co-culture medium of SH-SY5Y and U87 cells with MPP+ treatment inhibited the proliferation of Jurkat cells compared to control medium without MPP+, even though the same concentration of MPP+ had very little toxicity to the Jurkat cell. Furthermore, co-culture medium with low concentration of MPP+ (100 µM) arrested Jurkat cells cycle in G2/M phase through increasing cell cycle division 2 (CDC2) and CyclinB1 expression level, whereas co-culture medium with high concentration of MPP+ (500 µM) induced Jurkat cell necrosis through cellular swelling and membrane breakage. Our data implies that damaged dopamine neurons with glial cells can lead to the reduced number or inhibited proliferation activity of peripheral T cells. 相似文献
992.
Shijun Yue Yuping Tang Chengmei Xu Shujiao Li Yue Zhu Jin-Ao Duan 《International journal of molecular sciences》2014,15(9):16760-16771
Two new quinochalcone C-glycosides, named hydroxysafflor yellow B (1) and hydroxysafflor yellow C (2), along with two known quinochalcone C-glycosides, safflomin C (3) and saffloquinoside C (4), and one known flavanone, (2R)-4'',5-dihydroxyl-6,7-di-O-β-d-glucopyranosyl flavanone (5), were isolated from the florets of Carthamus tinctorius. Their structures were determined by extensive spectroscopic (UV, IR, HR-ESI-MS, 1D and 2D NMR) analyses. In addition, these quinochalcone C-glycosides together with hydroxysafflor yellow A and anhydrosafflor yellow B were evaluated for their anti-oxidative effects against H2O2-induced cytotoxicity in cultured H9c2 cells. Among them, compound 2 exhibited significant anti-oxidative effects. 相似文献
993.
Sin Hang Lee Jessica S. Vigliotti Veronica S. Vigliotti William Jones David M. Shearer 《International journal of molecular sciences》2014,15(3):4284-4298
The diagnoses of Lyme disease based on clinical manifestations, serological findings and detection of infectious agents often contradict each other. We tested 52 blind-coded serum samples, including 20 pre-treatment and 12 post-treatment sera from clinically suspect Lyme disease patients, for the presence of residual Lyme disease infectious agents, using nested PCR amplification of a signature segment of the borrelial 16S ribosomal RNA gene for detection and direct DNA sequencing of the PCR amplicon for molecular validation. These archived sera were split from the samples drawn for the 2-tier serology tests performed by a CDC-approved laboratory, and are used as reference materials for evaluating new diagnostic reagents. Of the 12 post-treatment serum samples, we found DNA evidence of a novel borrelia of uncertain significance in one, which was also positive for the 2-tier serology test. The rest of the post-treatment sera and all 20 control sera were PCR-negative. Of the 20 pre-treatment sera from clinically suspect early Lyme disease patients, we found Borrelia miyamotoi in one which was 2-tier serology-negative, and a Borrelia burgdorferi in two—one negative and one positive for 2-tier serology. We conclude that a sensitive and reliable DNA-based test is needed to support the diagnosis of Lyme disease and Lyme disease-like borreliosis. 相似文献
994.
Wenqing Li Dongsheng Yu Shuo Gao Jiacheng Lin Zhuoyu Chen Wei Zhao 《International journal of molecular sciences》2014,15(6):10766-10779
Candida albicans is strongly associated with severe early childhood caries (S-ECC). However, the roles of secreted aspartyl proteinases (Saps), an important virulence factor of C. albicans, in the progress of S-ECC are not clear. In our study, the Saps activities were evaluated by the yeast nitrogen base–bovine serum albumi (YNB–BSA) agar plate method and by the MTT method with bovine serum albumin (BSA) as the substrate. Genotypes of C. albicans and gene expression of Sap1–5 were evaluated. The relationships of Saps activities and genotypes with S-ECC were analyzed. The results showed that enzyme activities of Saps in the S-ECC group were significantly higher than those in the caries free (CF) group (p < 0.05). Genotypes A, B and C were detected in the S-ECC group, and genotypes A and C were detected in the CF group. In the genotype A group, Saps activity in the S-ECC group was significantly different from that in the CF group (p < 0.05). The gene expression level of Sap1 in the S-ECC group was significantly higher than that in the CF group (p = 0.001), while Sap4 expression was significantly lower than that in the CF group (p = 0.029). It can be concluded that Sap1–5 are the predominant proteinase genes expressed in C. albicans from dental biofilm and Sap1 may play an important role in the development of S-ECC. 相似文献
995.
996.
Junjie Zhang Fei Guo Lei Wang Wei Zhao Da Zhang Heying Yang Jiekai Yu Lili Niu Fuquan Yang Shu Zheng Jiaxiang Wang 《International journal of molecular sciences》2014,15(9):16186-16195
Wilms’ tumor is one of the most common malignant tumors observed in children, and its early diagnosis is important for late-stage treatment and prognosis. We previously screened and identified protein markers for Wilms’ tumor; however, these markers lacked specificity, and some were associated with inflammation. In the current study, serum samples from children with Wilms’ tumors were compared with those of healthy controls and patients with systemic inflammatory response syndrome (SIRS). After exclusion of factors associated with inflammation, specific protein markers for Wilms’ tumors were identified. After comparing the protein peak values obtained from all three groups, a protein with a m/z of 6438 Da was specified. Purification and identification of the target protein using high-pressure liquid chromatography (HPLC) and two-dimensional liquid chromatography-linearion trap mass spectrometry(2D-LC-LTQ-MS) mass spectrometry, respectively, revealed that it was apolipoprotein C-I (APO C-I). Thus, APO C-I is a specific protein marker for Wilms’ tumor. 相似文献
997.
Cheng Du Li Chen Haijun Zhang Zhongchao Wang Wenchao Liu Xiaodong Xie Manjiang Xie 《International journal of molecular sciences》2014,15(11):20706-20722
Increasing evidence suggests that caveolin-1 and large conductance Ca2+-activated potassium (BKCa) channels are implicated in the carcinogenesis processes, including cell proliferation and invasion. These two proteins have been proven to interact with each other in vascular endothelial and smooth muscle cells and modulate vascular contractility. In this study, we investigated the probable interaction between caveolin-1 and BKCa in MCF-7 breast cancer cells. We identified that caveolin-1 and BKCa were co-localized and could be reciprocally co-immunoprecipitated in human breast cancer MCF-7 cells. siRNA mediated caveolin-1 knockdown resulted in activation and increased surface expression of BKCa channel, and subsequently promoted the proliferation and invasiveness of breast cancer cells. These effects were attenuated in the presence of BKCa-siRNA. Conversely, up-regulated caveolin-1 suppressed function and surface expression of BKCa channel and exerted negative effects on breast cancer cell proliferation and invasion. Similarly, these opposing effects were abrogated by BKCa up-regulation. Collectively, our findings suggest that BKCa is a critical target for suppression by caveolin-1 in suppressing proliferation and invasion of breast cancer cells. The functional complex of caveolin-1 and BKCa in the membrane microdomain may be served as a potential therapeutic target in breast cancer. 相似文献
998.
Wen-Kai Xia Tian-Bo Ding Jin-Zhi Niu Chong-Yu Liao Rui Zhong Wen-Jia Yang Bin Liu Wei Dou Jin-Jun Wang 《International journal of molecular sciences》2014,15(3):3711-3728
Chitin synthase synthesizes chitin, which is critical for the arthropod exoskeleton. In this study, we cloned the cDNA sequences of a chitin synthase 1 gene, PcCHS1, in the citrus red mite, Panonychus citri (McGregor), which is one of the most economically important pests of citrus worldwide. The full-length cDNA of PcCHS1 contains an open reading frame of 4605 bp of nucleotides, which encodes a protein of 1535 amino acid residues with a predicted molecular mass of 175.0 kDa. A phylogenetic analysis showed that PcCHS1 was most closely related to CHS1 from Tetranychus urticae. During P. citri development, PcCHS1 was constantly expressed in all stages but highly expressed in the egg stage (114.8-fold higher than in the adult). When larvae were exposed to diflubenzuron (DFB) for 6 h, the mite had a significantly high mortality rate, and the mRNA expression levels of PcCHS1 were significantly enhanced. These results indicate a promising use of DFB to control P. citri, by possibly acting as an inhibitor in chitin synthesis as indicated by the up-regulation of PcCHS1 after exposure to DFB. 相似文献
999.
1000.
Yan-Bo Zhang Xiulian Wang Edward A. Meister Ke-Rui Gong Shao-Chun Yan Guo-Wei Lu Xun-Ming Ji Guo Shao 《International journal of molecular sciences》2014,15(6):10999-11012
It is well known that cobalt chloride (CoCl2) can enhance the stability of hypoxia-inducible factor (HIF)-1α. The aim of this study is to detect the effect of CoCl2 on the hypoxia tolerance of mice which were repeatedly exposed to autoprogressive hypoxia. Balb/c mice were randomly divided into groups of chemical pretreatment and normal saline (NS), respectively injected with CoCl2 and NS 3 h before exposure to hypoxia for 0 run (H0), 1 run (H1), and 4 runs (H4). Western Blot, electrophoretic mobility shift assay (EMSA), extracellular recordings population spikes in area cornus ammonis
I (CA 1) of mouse hippocampal slices and real-time were used in this study. Our results demonstrated that the tolerance of mice to hypoxia, the changes of HIF-1α protein level and HIF-1 DNA binding activity in mice hippocampus, the mRNA level of erythropoietin (EPO) and vascular endothelial growth factor (VEGF), and the disappearance time of population spikes of hippocampal slices were substantially different between the control group and the CoCl2 group. Over-induction of HIF-1α by pretreatment with CoCl2 before hypoxia did not increase the hypoxia tolerance. 相似文献