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排序方式: 共有970条查询结果,搜索用时 15 毫秒
961.
962.
Toll-like receptors (TLRs), which are mainly expressed in antigen presenting cells, perform a critical role in innate immunity by recognizing the specific structural patterns of pathogens and transducing signals to induce an inflammatory reaction. Although it has been reported that various solid cancers express endosomal TLRs, TLR3, 7, 8, and 9, the cellular and molecular function of TLRs in tumorigenesis has not yet been elucidated. In this report, we identified the expression of TLR3 and TLR7 in the human breast cancer cell line MCF-7 and found that TLRs stimulated with their specific ligand induced an anti-tumoral effect in this cell line. Among four synthetic commercial agonists of TLR3 and 7, Poly(I:C) and imiquimod (IMQ) proved to have superior anti-tumoral activity over the other agonists. A decreased growth rate was observed in MCF-7 cells treated with either TLR agonist. The decreased growth rate was due to autophagy and autophagy-induced cell death because treatment with 3-methyladenine, inhibitor of autophagy rescued the growth rate and increased the expression levels of autophagy-related genes. Moreover, survival of MCF-7 cells significantly decreased when the cells were stimulated simultaneously with TLR agonists and radiation exposure. Therefore, this study can be applied to developing a therapeutic adjuvant of TLR agonists in radiotherapy for radio-resistant breast cancer treatment. 相似文献
963.
David B. Allison Myles S. Faith Moonseong Heo Diana Townsend-Butterworth David F. Williamson 《Obesity (Silver Spring, Md.)》1999,7(4):342-354
ALLISON, DAVID B., MYLES S. FAITH, MOONSEONG HEO, DIANA TOWNSEND-BUTTERWORTH, AND DAVID F. WILLIAMSON. Meta-analysis of the effect of excluding early deaths on the estimated relationship between body mass index and mortality. Obes Res. Objectives: Prospective cohort studies typically observe U-or J-shaped relationships between body mass index (BMI) (kg/m2) and mortality. However, some studies suggest that the elevated mortality at lower BMIs is due to confounding by pre-existing occult disease and recommend eliminating subjects who die during the first several (k) years of follow-up. This meta-analysis tests the effects of such early death exclusion on the BMI-mortality association. Research Methods and Procedures: Studies identified from MEDLINE, review articles, ancestry analyses, and the “invisible college.” Included studies: 1) measured relative body weight at baseline; 2) inchded at least 1000 subjects; 3) reported results with and without early-death exclusion, or relevant data; and 4) did not study exclusively diseased populations. Blank tables were mailed to 131 investigators covering 59 databases. Completed tables (n = 16 databases), electronic raw data (n = 7 databases), and original articles (n = 6 databases) provided final data. Meta-analytic regressions compared the BMI-mortality association with and without early death exclusion. The sample included 29 studies and 1,954,345 subjects. Results: The effect of eliminating early deaths was statistically significant but minuscule in magnitude. Implementation of early death exclusion was estimated to shift the BMI associated with minimum mortality only 0. 4 units for men and 0. 6 units for women at age 50. Even at a BMI 16, the estimated relative risk (compared to BMI 25) decreased only 0. 008 units for men and 0. 076 units for women at age 50. Discussion: Results indicate that either pre-existing disease does not confound the BMI—mortality association or eliminating early deaths is inefficient for reducing that confounding. 相似文献
964.
Ju Jung-Hyun Oh Baek-Rock Heo Sun-Yeon Lee Young-Uk Shon Jung-hoon Kim Chul-Ho Kim Young-Min Seo Jeong-Woo Hong Won-Kyung 《Bioprocess and biosystems engineering》2020,43(1):33-43
Bioprocess and Biosystems Engineering - In this study, to produce adipic acid, mutant strains of Candida tropicalis KCTC 7212 deficient of AOX genes encoding acyl-CoA oxidases which are important... 相似文献
965.
Miyoung Kim Se Ran Heo Soon Hee Choi Hyelin Kwon Jeong Su Park Moon-Woo Seong Do-Hoon Lee Kyoung Un Park Junghan Song Eui-Chong Kim 《BMC microbiology》2008,8(1):233
Background
Three phenotypic identification systems (MicroScan, VITEK 2, and Crystal GP) were evaluated for their accuracy to identify coagulase-negative staphylococci (CNS). A total of 120 clinical isolates confirmed to be CNS via 16S rRNA sequencing and analysis with the MicroSeq 500 v2.0 database were assessed. 相似文献966.
Shunfu Piao Sun-Hye Lee Hyunjoon Kim Soohwan Yum Jennifer L. Stamos Yongbin Xu Su-Jin Lee Jaewon Lee Sangtaek Oh Jin-Kwan Han Bum-Joon Park William I. Weis Nam-Chul Ha 《PloS one》2008,3(12)
Wnt/β-catenin signaling plays a central role in development and is also involved in a diverse array of diseases. Binding of Wnts to the coreceptors Frizzled and LRP6/5 leads to phosphorylation of PPPSPxS motifs in the LRP6/5 intracellular region and the inhibition of GSK3β bound to the scaffold protein Axin. However, it remains unknown how GSK3β is specifically inhibited upon Wnt stimulation. Here, we show that overexpression of the intracellular region of LRP6 containing a Ser/Thr rich cluster and a PPPSPxS motif impairs the activity of GSK3β in cells. Synthetic peptides containing the PPPSPxS motif strongly inhibit GSK3β in vitro only when they are phosphorylated. Microinjection of these peptides into Xenopus embryos confirms that the phosphorylated PPPSPxS motif potentiates Wnt-induced second body axis formation. In addition, we show that the Ser/Thr rich cluster of LRP6 plays an important role in LRP6 binding to GSK3β. These observations demonstrate that phosphorylated LRP6/5 both recruits and directly inhibits GSK3β using two distinct portions of its cytoplasmic sequence, and suggest a novel mechanism of activation in this signaling pathway. 相似文献
967.
968.
Using cDNA microarrays, we have conducted a systematic characterization of global gene expression in v-raf or v-raf/v-myc transformed rat liver epithelial (RLE) cell lines exhibiting both non-metastatic and metastatic phenotypes. Seven transformed cell lines were compared with the non-transformed parental RLE cell. The hierarchical clustering analysis of gene expression profiles revealed two groups reflecting the in vivo metastatic potential of the cells. Surprisingly, one non-metastatic cell line T1 was co-clustered with metastatic cell lines, suggesting that T1 underwent significant genetic changes. The T1 cell line was further compared against all the metastatic cell lines in order to reveal the critical genes required for metastatic conversion but not expressed in the T1. These data demonstrated that expression of genes involved in apoptosis and immune cell homing were altered in all metastatic cell lines. Survival of both intravasated cells in circulation systems and extravasated cells in a new tissue environment might be critical for the final step in the metastatic process. Our study provides gene expression signatures consistent with two critical events in the metastatic process, namely, the acquisition of early homing capacity and increased survival potential of the tumor cells. 相似文献
969.
N‐acetylcysteine normalizes the urea cycle and DNA repair in cells from patients with Batten disease
Batten disease is an inherited disorder characterized by early onset neurodegeneration due to the mutation of the CLN3 gene. The function of the CLN3 protein is not clear, but an association with oxidative stress has been proposed. Oxidative stress and DNA damage play critical roles in the pathogenesis of neurodegenerative diseases. Antioxidants are of interest because of their therapeutic potential for treating neurodegenerative diseases. We tested whether N‐acetylcysteine (NAC), a well‐known antioxidant, improves the pathology of cells from patients with Batten disease. At first, the expression levels of urea cycle components and DNA repair enzymes were compared between Batten disease cells and normal cells. We used both mRNA expression levels and Western blot analysis. We found that carbamoyl phosphate synthetase 1, an enzyme involved in the urea cycle, 8‐oxoguanine DNA glycosylase 1 and DNA polymerase beta, enzymes involved in DNA repair, were expressed at higher levels in Batten disease cells than in normal cells. The treatment of Batten disease cells with NAC for 48 h attenuated activities of the urea cycle and of DNA repair, as indicated by the substantially decreased expression levels of carbamoyl phosphate synthetase 1, 8‐oxoguanine DNA glycosylase 1 and DNA polymerase beta proteins compared with untreated Batten cells. NAC may serve in alleviating the burden of urea cycle and DNA repair processes in Batten disease cells. We propose that NAC may have beneficial effects in patients with Batten disease. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
970.
In S. Kim Xianghao Ren Jin-Soo Chang Jin Wook Lee Hye-Weon Yu Sung-Jo Kim Jung Sun Heo Am Jang Ho Jae Han 《Biotechnology and Bioprocess Engineering》2011,16(2):400-406
N,N-diethyl-m-toluamide (DEET) is an insect repellent used worldwide, and a common micropollutant in aquatic environments. However, few
studies have addressed the molecular mechanism of DEET toxicity and its effects on cell growth and apoptosis. The purpose
of this study was to investigate the effect of DEET on the expression of the cell cycle and apoptosis regulatory proteins
in human BE(2)-M17 cells. The results showed that DEET significantly decreased the cell viability (40.6 ∼ 68.9% of control)
at concentrations of 500 ∼ 4,000 mg/L. Also, DEET significantly decreased the expressions of CDK 2, CDK 4, and cyclin D1 (3.9
∼ 86.6% of control), at concentrations of 50 ∼ 400 mg/L but from 100 mg/L for cyclin E. Furthermore, DEET significantly increased
the expression of caspase-3 (223.1 ∼ 1,770.6% of control), but significantly decreased Bcl-2 expression (46.1 ∼ 86.3% of control)
at all concentrations tested. In conclusion, DEET partially affected the expression of CDK/cyclin molecules, but fully affected
the expressions of caspase-3 and Bcl-2 in BE(2)-M17 cells. 相似文献