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71.
Sanhao Ji Yong Ju Hua Fu Yufen Zhao Tommy Johansson Jacek Stawinski 《Nucleosides, nucleotides & nucleic acids》2013,32(7):771-784
2-,3-,4-Pyridylphosphonates and their phosphonothioate congeners were analyzed by electrospray ionization multistage tandem mass spectrometry (ESI-MSn). It was found that the fragmentation pathways of these compounds were not influenced to any detectable extent by the stereochemistry at the phosphorus centers but were sensitive to the position of a nitrogen atom in the pyridine ring of these compounds. Possible mechanisms for fragmentations of the investigated compounds are discussed in detail. 相似文献
72.
73.
The physiological ecology of Prasiola stipitata was examined in situ from two supralittoral sites in the Bay of Fundy (Nova Scotian, Canada) during November 2011, when the population was undergoing major expansion. Photosynthetic parameters (effective quantum yield, ΦPSII, maximum quantum yield, Fv/Fm, and relative electron transport rate, rETR) were evaluated using chlorophyll fluorescence of PSII. A largely shaded and continuously moist population showed no change in ΦPSII from one hour after sunrise to sunset in which natural irradiance varied between 3 and 300 μmol photons m?2 s?1. High irradiance (up to 1800 μmol photons m?2 s?1) had no apparent negative impacts on either quantum yield or rETR, but high desiccation in the field reduced quantum yield to almost zero. When thalli were brought into the laboratory, no change in Fv/Fm was observed up to 60% dehydration; however, there was a steep decline in Fv/Fm between 60% and 85% dehydration. Thalli showed complete recovery of Fv/Fm within one hour of reimmersion in seawater after 2 days of desiccation. After 15 days of desiccation full recovery required 24 h and after 30 days of desiccation thalli showed only partial recovery. These observations confirm the adaptation to photosynthesis in high irradiances and the rapid recovery following extreme desiccation observed in other Prasiola species. 相似文献
74.
A new species, Obolarina persica, is described from Iran. It is widely associated with dying Quercus brantii, on which it produces charcoal-like stromata. The fungus described herein differs from the other described species, Ob. dryophila, primarily in its much larger ascospores. 相似文献
75.
Silkworm hemolymph (SH) was found to exhibit anti-apoptotic activities in mammalian and insect cell systems. An anti-apoptotic mechanism of SH was investigated in a staurosporine-induced HeLa cell using flow cytometry, caspase assay, Immunoblot, and Immunochemistry. The addition of 5% SH to the medium resulted in lower intracellular activities of caspase-3 and caspase-9 after 0.6 μM of staurosporine treatment; however, SH did not directly inhibit the activities of those enzymes. This suggests SH inhibits the event upstream of these caspase activation steps, such as mitochondrial level events. We found from Immunoblot and Immunochemistry that cytochrome c release from the mitochondria was blocked by SH. SH also inhibited Bax translocation to the mitochondria. On the contrary, SH did not block the apoptosis when Bax is not involved in promoting apoptosis. With these results, we propose that SH protects mitochondria from apoptosis signal via blocking Bax translocation, and the subsequent apoptotic events are then inhibited. The inhibition of apoptosis using SH and its components may lead to new approaches for the minimization of cell death during commercial animal cell cultures. 相似文献
76.
Chen Tian Guoguang Zheng Zhipan Cao Qiao Li Zhenyu Ju Jinhong Wang Weiping Yuan Tao Cheng 《Cell cycle (Georgetown, Tex.)》2013,12(2):322-334
Normal hematopoiesis is suppressed during the development of leukemia. In the T-ALL leukemia mouse model described in our recent study (Hu X, et al. Blood 2009), the impacts of leukemic environment on normal hematopoietic stem cells (HSCs) and hematopoietic progenitor cells (HPCs) were distinct, in that normal HSCs were preserved in part because of increased mitotic quiescence of HSCs and resulting exhaustion of HPCs proliferation. Stem cell factor (SCF) secreted by leukemic cells in Nalm6 B-ALL model was previously suggested to force normal HSCs/HPCs out of their bone marrow niches and allow leukemic cells to occupy the niches (Colmone A, et al. Science 2008). Here we found that stem cell factor (SCF) expression in PB and BM of T-ALL model was increased, but SCF mRNA and protein levels in normal hematopoietic cells were higher than those in leukemia cells, which suggested that upregulated SCF was mainly contributed by non-leukemic cells in response to the leukemia development. To further elucidate the molecular mechanisms, microarray analysis was conducted on normal HSCs in this model and verified by real-time RT-PCR. The expression of Hes1 and its downstream target p21 were elevated in normal HSCs, whereas their expression showed no significant alteration in HPCs. Interestingly, although overexpression of Hes1 by retroviral infection inhibited the in vitro colony formation of normal hematopoietic cells, in vivo results demonstrated that normal Lin- cells and HSPCs were better preserved when normal Lin- cells with Hes1 overexpression were co-transplanted with T-ALL leukemia cells. Our results suggested that the differential expression of Hes1 between HSCs and HPCs resulted in the distinct responses of these cells to the leukemic condition, and that overexpression of Hes1 could enhance normal HSPCs in the leukemic environment. 相似文献
77.
Jun Seo Goo Yo Na Kim Kyung Mi Choi In Sik Hwang Ji Eun Kim Young Ju Lee Moon Hwa Kwak Sun Bo Shim Seung Wan Jee Chul Joo Lim Je Kyung Seong Dae Youn Hwang 《Clinical proteomics》2013,10(1):10
Background
To characterize changes in global protein expression in kidneys of transgenic rats overexpressing human selenoprotein M (SelM) in response to increased bioabivility of selenium (Sel), total proteins extracted from kidneys of 10-week-old CMV/hSelM Tg and wild-type rats were separated by 2-dimensional gel electrophoresis and measured for changes in expression.Results
Ten and three proteins showing high antioxidant enzymatic activity were up- and down-regulated, respectively, in SelM-overexpressing CMV/hSelM Tg rats compared to controls based on an arbitrary 2-fold difference. Up-regulated proteins included LAP3, BAIAP2L1, CRP2, CD73 antigen, PDGF D, KIAA143 homolog, PRPPS-AP2, ZFP313, HSP-60, and N-WASP, whereas down-regulated proteins included ALKDH3, rMCP-3, and STC-1. After Sel treatment, five of the up-regulated proteins were significantly increased in expression in wild-type rats, whereas there were no changes in CMV/hSelM Tg rats. Only two of the down-regulated proteins showed reduced expression in wild-type and Tg rats after Sel treatment.Conclusions
These results show the primary novel biological evidences that new functional protein groups and individual proteins in kidneys of Tg rats relate to Sel biology including the response to Sel treatment and SelM expression. 相似文献78.
Yong-Sheng Xiao Qiang Gao Xiang-Nan Xu Yi-Wei Li Min-Jie Ju Ming-Yan Cai Chen-Xin Dai Jie Hu Shuang-Jian Qiu Jian Zhou Jia Fan 《PloS one》2013,8(8)
Purpose
To investigate the prognostic value of intratumoral invariant natural killer T (iNKT) cells and interferon-gamma (IFN-γ) in hepatocellular carcinoma (HCC) after curative resection.Experimental Design
Expression of TRAV10, encoding the Vα24 domain of iNKT cells, and IFN-γ mRNA were assessed by quantitative real-time polymerase chain reaction in tumor from 224 HCC patients undergoing curative resection. The prognostic value of these two and other clinicopathologic factors was evaluated.Results
Either intratumoral iNKT cells and IFN-γ alone or their combination was an independent prognostic factor for OS (P = 0.001) and RFS (P = 0.001) by multivariate Cox proportional hazards analysis. Patients with concurrent low levels of iNKT cells and IFN-γ had a hazard ratio (HR) of 2.784 for OS and 2.673 for RFS. The areas under the curve of iNKT cells, IFN-γand their combination were 0.618 vs 0.608 vs 0.654 for death and 0.591 vs 0.604 vs 0.633 for recurrence respectively by receiver operating characteristic curve analysis. The prognosis was the worst for HCC patients with concurrent low levels of iNKT cells and IFN-γ, which might be related with more advanced pTNM stage and more vascular invasion.Conclusions
Combination of intratumoral iNKT cells and IFN-γ is a promising independent predictor for recurrence and survival in HCC, which has a better power to predict HCC patients’ outcome compared with intratumoral iNKT cells or IFN-γ alone. 相似文献79.
80.
Eun Ju Lee Majid Rasool Kamli Smritee Pokharel Adeel Malik K. M. A. Tareq Abdul Roouf Bhat Hee-Bok Park Yong Seok Lee SangHoon Kim Bohsuk Yang Ki Young Chung Inho Choi 《PloS one》2013,8(11)