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41.
Three perglycosylated nordihydroguaiaretic acids (NDGA) were synthesized through the Huiseng 1,3-dipolar cycloaddition reaction. These sugar-NDGA conjugates containing triazole-linkages possessed good solubility in water. NDGA-(triazol-galactose)4 (12b) and NDGA-(triazol-glucose)4 (12c) were found to act as inhibitors against human hepatocellular carcinoma Hep3B cells in culture.  相似文献   
42.
Pancreatic cancer is being pursued as an immunotherapy target using antigen-specific vaccine approaches activating CD8(+) CTL and CD4(+) T-helper cells. CD8(+) CTL exert their anti-tumor effects in an HLA-restricted manner and only tumor cells carrying a matched HLA class I sub-type are targets for antigen-specific CTL. In the process of characterizing CD8(+) T cell responses against pancreatic cancer, we screened a number of human pancreatic tumor cell lines for HLA-A0201 positive (HLA-A2(+)) cell lines to be used in the evaluation of CTL function. This analysis revealed some new findings and discrepancies in the literature on the HLA sub-type of some commonly used pancreatic cell lines. We found that Capan-1 cells, originally reported to be HLA-A0201(+), actually only express HLA-A010101 and HLA-A300101 and were targets for HLA-A0201-restricted CTL only after transduction with an HLA-A0201-expressing lentivirus. Panc-1 cells were found to be HLA-A0201 positive, in agreement with published reports, while CF-Pac-1 cells were found to express both HLA-A020101 and HLA-A030101. We also found a normal human pancreatic ductal epithelial cell line, HPDE, to be HLA-A0201 positive. Our findings were verified with two different sequence-based typing methods, antibody staining followed by flow cytometry analysis, and functional analysis using an HLA-A0201-restricted peptide-specific T cell response.  相似文献   
43.
The eating and cooking qualities of rice grains are the major determinants of consumer preference and, consequently, the economic value of a specific rice variety. These two qualities are largely determined by the physicochemical properties of the starch, i.e. the starch composition, of the rice grain. In our study, we determined the genetic factors responsible for the physicochemical properties of starch in recombinant inbred lines (RILs) of japonica cv. Tainung 78 × indica cv. Taichung Sen 17 (TCS 17) cultivated over two crop seasons by examining palatability characteristics and several Rapid Viscosity Analyzer (RVA) parameters. Thirty-four quantitative trait loci (QTLs), each explaining between 1.2 and 78.1 % phenotypic variation, were mapped in clusters on eight chromosomes in 190 RILs genotyped with 139 markers. Ten pairs of QTLs were detected in the two environments, of which seven were in agreement with previous findings, suggesting that these QTLs may express stable experimental populations across various environments. Waxy (Wx), which controls amylose synthesis, was determined to be a primary gene regulating the physicochemical properties of cooked rice grains, as indicated by the presence of a major QTL cluster on chromosome 6 and by marker regression analysis. Six starch synthesis-related genes (SSRGs) which were located in the QTL intervals significantly differed in terms of gene expression between the two parents during grain-filling and were important genetic factors affecting physicochemical properties. The expression of four genes, PUL, ISA2, GBSSI, and SSII-3, was significantly upregulated in TCS 17, and this expression was positively correlated with six traits. The effects of the six SSRGs and gene interaction depended on genetic background and environment; grain quality may be fine tuned by selecting for SBE4 for japonica and PUL for indica. We provide valuable information for application in the breeding of new rice varieties as daily staple food and for use in industrial manufacturing by marker-assisted selection.  相似文献   
44.
GTP cyclohydrolase I (GCH), an oligomeric protein composed of 10 identical subunits, is required for the synthesis of neurotransmitters; mutations in GCH are associated with dopa-responsive dystonia (DRD) and hyperphenylalaninemia. Mutated GCH proteins are unstable and prone to dominant-negative effect. We show herein that expression of the GCH mutant GCH-201E or the splicing variant GCH-II caused intracellular inclusion bodies. When Hsp27 was expressed together with the GCH mutants, Hsp27 expression decreased the formation of inclusion bodies by GCH (as assessed by immunofluorescence) and decreased the amount of insoluble GCH mutant proteins (as assessed by Western blot). Transfection of pcDNA-Hsp27-S3D, a phosphorylation-mimicry Hsp27 mutant, was more effective at the mutated GCH proteins than transfection with pcDNA-Hsp27, but okadaic acid, a phosphatase inhibitor, enhanced the effect of pcDNA-Hsp27. Hsp27-S3D also abolished the dominant-negative action of GCH-II. The mutated GCH proteins interacted with the wild-type GCH protein; the inclusion bodies were positive for lysosomal marker LAMP1, soluble in 2% SDS, and were not ubiquitinated. Phophorlyated Hsp27 also decreased the inclusion body formation by the huntingtin polyglutamines. Therefore, diseases involving mutated oligomeric proteins would be manageable by chaperone therapies.  相似文献   
45.
Lin SY  Chen CL  Wu YL  Yang YC  Hwu YM 《Cell proliferation》2008,41(3):492-505
Abstract. Objectives : To investigate potential interactions between bone morphogenetic protein (BMP) and Wnt signalling on differentiating mouse embryonic stem cells (mESC). Materials and methods : Mouse embryonic stem cells were cultured with differing combinations of Wnt3a, BMP4 and inhibitors of Wnt, BMP, PI-3K (phosphoinositide 3-kinase), p38, ERK1/2 (extracellular signal-regulated kinase 1/2) and JNK (c-Jun N-terminal kinase) pathways. Results : We found that Wnt3a synergized with BMP4 to promote mESC proliferation. Furthermore, the relative ratio of Wnt3a to BMP4 doses was critical to their synergistic effects, which could be abolished by using Dkk-1, noggin or the inhibitors of PI-3K, p38, ERK1/2 and JNK pathways. We also demonstrated that combination of Wnt3a and BMP4 could suppress ectodermal differentiation of mESCs. Moreover, inhibitors of PI-3K, p38, ERK1/2 and JNK pathways could negate this effect. Conclusion : Relative ratio of Wnt3a to BMP4 doses is critical to their synergistic effect on differentiating mESC proliferation, which may work through PI-3K, p38, ERK1/2 and JNK pathways.  相似文献   
46.
Myxoid liposarcoma (MLS) is a soft tissue sarcoma characterized by a recurrent t(12;16) translocation. Although tumors are initially radio- and chemosensitive, the management of inoperable or metastatic MLS can be challenging. Therefore, our aim was to identify novel targets for systemic therapy. We performed an in vitro high-throughput drug screen using three MLS cell lines (402091, 1765092, DL-221), which were treated with 273 different drugs at four different concentrations. Cell lines and tissue microarrays were used for validation. As expected, all cell lines revealed a strong growth inhibition to conventional chemotherapeutic agents, such as anthracyclines and taxanes. A good response was observed to compounds interfering with Src and the mTOR pathway, which are known to be affected in these tumors. Moreover, BIRC5 was important for MLS survival because a strong inhibitory effect was seen at low concentration using the survivin inhibitor YM155, and siRNA for BIRC5 decreased cell viability. Immunohistochemistry revealed abundant expression of survivin restricted to the nucleus in all 32 tested primary tumor specimens. Inhibition of survivin in 402-91 and 1765-92 by YM155 increased the percentage S-phase but did not induce apoptosis, which warrants further investigation before application in the treatment of metastatic MLS. Thus, using a 273-compound drug screen, we confirmed previously identified targets (mTOR, Src) in MLS and demonstrate survivin as essential for MLS survival.  相似文献   
47.
The tumor-associated-Ag MART-1 is expressed by most human melanomas. The genes encoding an alphabeta TCR from a MART-1-specific, HLA-A2-restricted, human T cell clone have been efficiently transferred and expressed in human PBL. These retrovirally transduced PBL cultures were MART-1 peptide reactive, and most cultures recognized HLA-A2+ melanoma lines. Limiting dilution clones were generated from three bulk transduced PBL cultures to investigate the function of individual clones within the transduced cultures. Twenty-nine of 29 CD8+ clones specifically secreted IFN-gamma in response to T2 cells pulsed with MART-1(27-35) peptide, and 23 of 29 specifically secreted IFN-gamma in response to HLA-A2+ melanoma lines. Additionally, 23 of 29 CD8+ clones lysed T2 cells pulsed with the MART-1(27-35) peptide and 15 of 29 lysed the HLA-A2+ melanoma line 888. CD4+ clones specifically secreted IFN-gamma in response to T2 cells pulsed with the MART-1(27-35) peptide. TCR gene transfer to patient PBL can produce CTL with anti-tumor reactivity in vitro and could potentially offer a treatment for patients with metastatic melanoma. This approach could also be applied to the treatment of other tumors and viral infections. Additionally, TCR gene transfer offers unique opportunities to study the fate of adoptively transferred T cells in vivo.  相似文献   
48.
Both neurocognitive deficits and schizophrenia are highly heritable. Genetic overlap between neurocognitive deficits and schizophrenia has been observed in both the general population and in the clinical samples. This study aimed to examine if the polygenic architecture of susceptibility to schizophrenia modified neurocognitive performance in schizophrenia patients. Schizophrenia polygenic risk scores (PRSs) were first derived from the Psychiatric Genomics Consortium (PGC) on schizophrenia, and then the scores were calculated in our independent sample of 1130 schizophrenia trios, who had PsychChip data and were part of the Schizophrenia Families from Taiwan project. Pseudocontrols generated from the nontransmitted parental alleles of the parents in these trios were compared with alleles in schizophrenia patients in assessing the replicability of PGC‐derived susceptibility variants. Schizophrenia PRS at the P‐value threshold (PT) of 0.1 explained 0.2% in the variance of disease status in this Han‐Taiwanese samples, and the score itself had a P‐value 0.05 for the association test with the disorder. Each patient underwent neurocognitive evaluation on sustained attention using the continuous performance test and executive function using the Wisconsin Card Sorting Test. We applied a structural equation model to construct the neurocognitive latent variable estimated from multiple measured indices in these 2 tests, and then tested the association between the PRS and the neurocognitive latent variable. Higher schizophrenia PRS generated at the PT of 0.1 was significantly associated with poorer neurocognitive performance with explained variance 0.5%. Our findings indicated that schizophrenia susceptibility variants modify the neurocognitive performance in schizophrenia patients.  相似文献   
49.
OBJECTIVES: To investigate the insulin sensitivity in normotensive offspring of hypertensive parents. SUBJECTS: Fifteen young normotensive offspring of hypertensive parents were paired with 15 controls matched for age, sex and body mass index. METHODS: The insulin sensitivity was investigated by 75 g oral glucose tolerance test (OGTT) and modified insulin suppression test. A high-fat mixed meal was administered to observe the changes of TG levels. RESULTS: The plasma glucose and serum insulin responses to oral glucose challenge were comparable between both groups. High-fat mixed meal made no difference in the plasma glucose, serum triglyceride or insulin between the 2 groups. With the modified insulin suppression test, the steady-state plasma glucose levels (SSPG) were higher in the offspring of parents with essential hypertension (138+/-43 mg/dl) than in the control group (95+/-26 mg/dl). The diastolic blood pressure and heart rate of the offspring of hypertensive parents are also higher than the control group. CONCLUSIONS: Insulin resistance exists in young normotensive offspring of hypertensive parents, and the impairment of insulin-mediated glucose uptake in these subjects develop before any alteration of fasting and postprandial triglyceride.  相似文献   
50.
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