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991.
We have previously shown that human embryonic stem cells can be differentiated into embryonic and fetal type of red blood cells that sequentially express three types of hemoglobins recapitulating early human erythropoiesis. We report here that we have produced iPS from three somatic cell types: adult skin fibroblasts as well as embryonic and fetal mesenchymal stem cells. We show that regardless of the age of the donor cells, the iPS produced are fully reprogrammed into a pluripotent state that is undistinguishable from that of hESCs by low and high-throughput expression and detailed analysis of globin expression patterns by HPLC. This suggests that reprogramming with the four original Yamanaka pluripotency factors leads to complete erasure of all functionally important epigenetic marks associated with erythroid differentiation regardless of the age or the tissue type of the donor cells, at least as detected in these assays. The ability to produce large number of erythroid cells with embryonic and fetal-like characteristics is likely to have many translational applications. 相似文献
992.
Feasibility study of a cyclic anoxic/aerobic two-stage MBR for treating ABS resin manufacturing wastewater 总被引:3,自引:0,他引:3
This study investigated the feasibility and the treatment efficiency of a cyclic anoxic/aerobic two-stage MBR for treating polymeric industrial wastewater. The anoxic/aerobic hybrid MBR was operated without sludge withdrawal except sampling during the study. The results showed that the highest COD organic loading rate of 8.7 kg COD/m3 day from bioreactor was obtained at phase 3. The system achieved 97% BOD5 and 89% COD removal. It also revealed that 93% of COD removal was contributed by bioreactor at phase 3 and the similar results happened to phases 1 and 2. The highest TN and TKN removals for each phase were 60, 74, 80% and 61, 74, 81%, respectively and limited by nitritation step. SEM images of nascent and fouled membranes were offered to evaluate the cleaning method. The system was operated for 174 days, resulting in high degradation rate, flexibility towards influent fluctuations and limited sludge production. 相似文献
993.
Cho BO Jin CH Park YD Ryu HW Byun MW Seo KI Jeong IY 《Bioscience, biotechnology, and biochemistry》2011,75(7):1306-1311
Isoegomaketone (IK) is an essential oil component of Perilla frutescens (L.), but the mechanism by which IK induces apoptosis has never been studied. The purpose of this study was to elucidate the IK-induced apoptotic pathway in DLD1 human colon cancer cells. We observed that IK treatment over 24 h significantly inhibited cell viability in a dose-dependent manner. We also found that IK triggered cleavage of PARP. Moreover, IK treatment resulted in cleavage of caspase-8, -9, and -3 in a dose- and time-dependent manner. IK treatment also resulted in cleavage of Bid and translocation of Bax, and triggered the release of cytochrome c from the mitochondria to the cytoplasm. Furthermore, it resulted in the translocation of apoptosis inducing factor (AIF), a caspase-independent mitochondrial apoptosis factor, from the mitochondria into the nucleus. Overall, these results suggest that IK induces apoptosis through caspase-dependent and capase-independent pathways in DLD1 cells. 相似文献
994.
The millipede genus Chamberlinius is basically confined to Taiwan, with only one of the four known species presumably introduced to southern Japan. Both previously known species are redescribed, based on new material: Chamberlinius hualienensis Wang, 1956 (the type species) and Chamberlinius piceofasciatus (Gressitt, 1941), the latter being a new subjective senior synonym of Chamberlinius shengmui Wang, 1957, syn. n. Two further congeners are described as new: Chamberlinius pessior sp. n. and Chamberlinius sublaevus sp. n. The genus is re-diagnosed, all of its four species are keyed, and their distributions mapped. The tribe Chamberlinini is reclassified and, based on gonopod traits, shown to comprise the following five genera: Chamberlinius Wang, 1956, Haplogonosoma Brölemann, 1916, Riukiupeltis Verhoeff, 1939, Aponedyopus Verhoeff, 1939 and Geniculodesmus Chen, Golovatch and Chang, 2008. 相似文献
995.
Kwak SJ Paeng J Kim do H Lee SH Nam BY Kang HY Li JJ Jung DS Han SH Ryu DR Park JT Chang TI Yoo TH Han DS Kang SW 《Apoptosis : an international journal on programmed cell death》2011,16(5):478-490
The kallikrein-kinin system (KKS) serves as the physiologic counterbalance to the renin-angiotensin system. This study was conducted to examine the changes in the expression of KKS components in podocytes under diabetic conditions and to elucidate the functional role of bradykinin (BK) in diabetes-associated podocyte apoptosis. Thirty-two rats were injected with either diluent (n = 16, C) or with streptozotocin intraperitoneally (n = 16, DM), and 8 rats from each group were treated with BK infusion for 6 weeks. Immortalized mouse podocytes were cultured in media containing 5.6 mmol/l glucose (NG), NG + 10(-7) mol/l AII (AII), or 30 mmol/l glucose (HG) with or without 10(-8) mol/l BK. Urinary albumin excretion was significantly higher in DM rats, and this increase was ameliorated by BK. Not only kininogen, kallikrein, and BK B1- and B2-receptor expression but also BK levels were significantly decreased in DM glomeruli and in cultured podocytes exposed to HG. The changes in the expressions of apoptosis-related molecules and the increase in the number of apoptotic cells in DM glomeruli as well as in HG- and AII-stimulated podocytes were significantly abrogated by BK. The suppressed KSS within podocytes under diabetic condition was associated with podocyte apoptosis, suggesting that BK may be beneficial in preventing podocyte loss in diabetic nephropathy. 相似文献
996.
HPV-16E7 is a major transforming protein, which has been implicated in the development of cervical cancer. The stability of E7 is thus important to ensure its fully functional status. Using the yeast two-hybrid system, we found that USP11 (ubiquitin-specific protease 11), a member of a protein family that cleaves polyubiquitin chains and/or ubiquitin precursors, interacts and forms a specific complex with HPV-16E7. Our results indicate that the USP11 can greatly increase the steady state level of HPV-16E7 by reducing ubiquitination and attenuating E7 degradation. In contrast, a catalytically inactive mutant of USP11 abolished the deubiquitinating ability and returned E7 to a normal rate of degradation. Moreover, USP11 not only protected E7 from ubiquitination but also influenced E7 function as a modulator of cell growth status. These results suggest that USP11 plays an important role in regulating the levels of E7 protein and subsequently affects the biological function of E7 as well as its contribution to cell transformation by HPV-16E7. 相似文献
997.
998.
Yesong Gu Antony Parker Teresa M Wilson Haibo Bai Dau-Yin Chang A-Lien Lu 《The Journal of biological chemistry》2002,277(13):11135-11142
Adenines mismatched with guanines or 7,8-dihydro-8-oxo-deoxyguanines that arise through DNA replication errors can be repaired by either base excision repair or mismatch repair. The human MutY homolog (hMYH), a DNA glycosylase, removes adenines from these mismatches. Human MutS homologs, hMSH2/hMSH6 (hMutSalpha), bind to the mismatches and initiate the repair on the daughter DNA strands. Human MYH is physically associated with hMSH2/hMSH6 via the hMSH6 subunit. The interaction of hMutSalpha and hMYH is not observed in several mismatch repair-defective cell lines. The hMutSalpha binding site is mapped to amino acid residues 232-254 of hMYH, a region conserved in the MutY family. Moreover, the binding and glycosylase activities of hMYH with an A/7,8-dihydro-8-oxo-deoxyguanine mismatch are enhanced by hMutSalpha. These results suggest that protein-protein interactions may be a means by which hMYH repair and mismatch repair cooperate in reducing replicative errors caused by oxidized bases. 相似文献
999.
Effector phenotype and immunologic specificity of T-cell-mediated adoptive therapy for a murine tumor that lacks intrinsic immunogenicity 总被引:2,自引:0,他引:2
The MCA 102 sarcoma has been defined by a variety of immunologic studies as a tumor lacking intrinsic immunogenicity. Nevertheless, we have recently demonstrated the feasibility of generating therapeutically effective lymphocytes for adoptive immunotherapy of this tumor. Procedures to achieve this required in vivo priming of syngeneic mice to elicit preeffector cells followed by in vitro sensitization (IVS) with tumor cells in the presence of IL-2. By selective depletion of T cell subsets in vivo, we identified the involvement of both CD4+ (L3T4+) and CD8+ (Lyt-2+) T cells in mediating tumor regression. The CD4+ cells exerted their helper function via the secretion of IL-2 because antitumor effects abrogated by depletion of CD4+ cells could be reconstituted by exogenous IL-2. In order to elicit preeffector cells with reactivity against the MCA 102 tumor, we found that in vivo sensitization could be accomplished with either the MCA 102 or MCA 106 tumor but not with the MCA 101 or MCA 105 tumor. Analysis of specificity of tumor stimulation during IVS of MCA 102 tumor-primed preeffector cells demonstrated cross-reactivity between not only the MCA 102 and MCA 106 tumors but also the MCA 105 tumor whereas the MCA 101 tumor was ineffective. In adoptive immunotherapy, transfer of IVS cells generated from MCA 102 tumor-primed and stimulated lymph node cells was able to mediate reductions of pulmonary metastases established from the MCA 102, MCA 105, and MCA 106 tumors but not from the MCA 101 tumor. We conclude that regression of the MCA 102 tumor is probably mediated through T cell recognition of a set of common tumor-associated Ag shared by several other syngeneic tumors. Immunologically, the tumor-associated Ag are characteristically different from classical tumor-specific transplantation Ag (TSTA) because immunity to TSTA on the MCA 105 or MCA 106 tumor does not cross-react with the MCA 102 tumor. Thus, this study demonstrates that Ag other than TSTA on chemically induced tumors can serve as target molecules for T cell-mediated adoptive immunotherapy. 相似文献
1000.