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81.
The regulation of regulation: interleukin‐10 increases CD4+ CD25+ regulatory T cells but impairs their immunosuppressive activity in murine models with schistosomiasis japonica or asthma 下载免费PDF全文
Qianqian Qi Ying Chi Jifeng Zhu Zhipeng Xu Xuefeng Wang Jason Hoellwarth Feng Liu Xiaojun Chen Chuan Su 《Immunology》2018,153(1):84-96
CD4+ CD25+ Foxp3+ regulatory T (Treg) cells play an important role in maintaining immune homeostasis. Interleukin‐10 (IL‐10), a cytokine with anti‐inflammatory capacities, also has a critical role in controlling immune responses. In addition, it is well known that production of IL‐10 is one of the suppression mechanisms of Treg cells. However, the action of IL‐10 on Treg cells themselves remains insufficiently understood. In this study, by using a Schistosoma japonicum‐infected murine model, we show that the elevated IL‐10 contributed to Treg cell induction but impaired their immunosuppressive function. Our investigations further suggest that this may relate to the up‐regulation of serum transforming growth factor (TGF‐β) level but the decrease in membrane‐bound TGF‐β of Treg cells by IL‐10 during S. japonicum infection. In addition, similar IL‐10‐mediated regulation on Treg cells was also confirmed in the murine model of asthma. In general, our findings identify a previously unrecognized opposing regulation of IL‐10 on Treg cells and provide a deep insight into the precise regulation in immune responses. 相似文献
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Inhibition of autophagy has been daily served as a promising anti-cancer treatment strategies. AstragalosideII (ASII), a main compound isolated from traditional Chinese medicine Radix Astragali, has been demonstrated to inhibit autophagy and reverse multidrug resistance in human hepatic cancer cells Bel-7402/5-FU. In this study, we inspected the function and mechanisms of ASII and cisplatin on autophagy in human cancer cells, and assessed the effect of ASII on cisplatin-induced apoptosis. We found ASII increased LC3II protein level, p62 protein level and GFP-LC3 puncta accumulation in human cancer cells. Furthermore, we found that ASII downregulated the expression of lysosomal cathepsinB/L (CTSB/L) in EBSS medium and affected the lysosomal acidification. Finally, we demonstrated that cisplatin induced protective autophagy which was involved of PI3K/Akt/mTOR pathway. Moreover, ASII in conjunction with cisplatin significant reduced cell viability, arrested in S phase and increased apoptosis. In conclusion, these findings suggested that ASII served as autophagy inhibitor which restored chemosensitivity of anticancer agent cisplatin and enhanced tumor cell death. 相似文献
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Simon Dagenais DC PhD Darren M. Roffey PhD Eugene K. Wai MD MSc Scott Haldeman DC MD PhD Jaime Caro MD MSc 《The spine journal》2009,9(11):944-957
Background contextLow back pain (LBP) is associated with high health-care utilization and lost productivity. Numerous interventions are routinely used, although few are supported by strong evidence. Cost utility analyses (CUAs) may be helpful to inform decision makers.PurposeTo conduct a systematic review of CUAs of interventions for LBP.Study designSystematic review.MethodsA search strategy combining medical subject headings and free text related to LBP and health economic evaluations was executed in MEDLINE. Cost utility analyses combined with randomized controlled trials for LBP were included. Studies that were published before 1998, non-English, decision analyses, and duplicate reports were excluded. Search results were evaluated by two reviewers, who extracted data independently related to clinical study design, economic study design, direct cost components, utility results, cost results, and CUA results.ResultsThe search produced 319 citations, and of these 15 met eligibility criteria. Most were from the United Kingdom (n=8), published in the past 3 years (n=12), studied chronic LBP or radiculopathy (n=13), and had a follow-up >12 months (n=13). Combined, there were 33 study groups who received a mean 2.1 interventions, most commonly education (n=17), exercise therapy (n=13), spinal manipulation therapy (n=7), surgery (n=7), and usual care from a general practitioner (n=7). Mean baseline utility was 0.57, improving to 0.67 at follow-up; the mean difference in utility improvement between study groups was 0.04. Based on available data and converted to US dollars, the cost per quality-adjusted life year ranged from $304 to $579,527, with a median of $13,015.ConclusionsFew CUAs were identified for LBP, and there was heterogeneity in the interventions compared, direct cost components measured, indirect costs, other methods, and results. Reporting quality was mixed. Currently published CUAs do not provide sufficient information to assist decision makers. Future CUAs should attempt to measure all known direct cost components relevant to LBP, estimate indirect costs such as lost productivity, have a follow-up period sufficient to capture meaningful changes, and clearly report methods and results to facilitate interpretation and comparison. 相似文献
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《Antiviral research》2009,81(3):280-287
The internal ribosome entry site (IRES) of hepatitis C virus (HCV) which governs the initiation of protein synthesis from viral RNA represents an ideal target for antisense approaches. Using an original bicistronic plasmid, we first established that sequence and translational activity of HCV IRESs cloned from six patients, whether responders or not to combination therapy, were conserved. We then tested the hypothesis that antisense molecules, i.e. short peptide nucleic acids (PNA), could inhibit HCV translation by binding to the highly conserved IIId or IV loop regions of the IRES. Five 6–10 mer PNAs were designed. They strongly inhibit HCV IRES-driven translation in a rabbit reticulocyte lysate assay. This inhibition was highly specific since corresponding PNAs with only one mismatch were inactive. Short phosphorothioate oligonucleotides of same sequence were unable to inhibit HCV translation. PNA molecule was shown to have anti-HCV activity in Huh-7.5 cells when electroporated with a full-length HCV genome construct. Using oligonucleotide as carrier, PNA was also transfected in HCV replicon-harboring cells and in JFH1 infected Huh-7.5 cells. 相似文献
88.
Jiang Jiang Kaifu Huo Shaopeng Chen Yunchang Xin Yongjian Xu Zhengwei Wu Zengliang Yu Paul K. Chu 《Biomaterials》2009,30(14):2661-2665
The genotoxicity of silicon (Si) is investigated by soaking crystalline Si in a complete culture medium for 60 days and conducting micronuclei tests (MNTs) utilizing hamster ovary (CHO) cells and its Ku80 deficient CHO mutant (xrs5) cells (DNA double-strand breaks repair deficiency). The intracellular concentrations of reactive oxygen/nitrogen species (ROS/RNS) on Si are determined to elucidate the relationship between ROS/RNS and Si-induced genotoxicity by using CHO cells. The cells are treated with ROS scavenger (dimethyl sulfoxide) and MNT are performed. The results indicate that the intracellular concentration of ROS and nitrogen oxide (NO) on Si is higher than those on the control group by about 38% and 12%. ROS/RNS include superoxide (O2?) anion, NO, and peroxynitrite (ONOO?) which can injure chromosomes and induce high cellular DNA double-strand breaks (DSBs). 相似文献
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Hilde Van Esch Luc Buekenhout Valerie Race Gert Matthijs 《European journal of medical genetics》2009,52(1):37-40
Expansion of the CGG trinucleotide repeat in the 5′ untranslated region of the fragile X mental retardation 1 (FMR1) gene within the premutation range is one of the known genetic factors associated with premature ovarian failure and earlier age at menopause. Studies have shown that approximately 16–26% of female carriers will develop premature ovarian failure, and current research is focussed on the identification of molecular factors that predict its occurrence in female carriers. In this report we present two sisters who are compound heterozygous for a premutation, and who were referred because of very early menopause, occurring at the age of 17 years in the youngest sister. Premature ovarian failure associated with FMR1 premutation at such an early age has not been reported in the literature before. 相似文献
90.
Ya Shen Yugui Cui Weidong Wan Xiaoping Zhou Lu Cheng Zuhong Lu Jiayin Liu 《南京医科大学学报(自然科学版)》2009,29(1):40-45
Objective:Nonsyndromic cleft lip with or without cleft palate(NSCL/P) is a common birth defect with unclear etiology. Both genetic and environmental factors may contribute to NSCL/P. Many genes have been identified as candidate genes associated with this disease. Interferon regulatory factor 6(IRF6) gene and transforming growth factor-a(TGFA) gene seem to be crucial in the predisposition of NSCL/P. Here we evaluated some single nucleotide polymorphisms(SNPs) loci of TGFA and IRF6 genes in Chinese nuclear fa... 相似文献