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41.
Background: Glycolysis was a representative hallmark in the tumor microenvironment (TME), and we aimed to explore the correlations between glycolysis with immune activity and clinical traits in bladder urothelial carcinoma (BLCA).Methods: Our study obtained glycolysis scores for each BLCA samples from TCGA by a single-sample gene set enrichment analysis (ssGSEA) algorithm, based on a glycolytic gene set. The relationship between glycolysis with prognosis, clinical characteristics, and immune function were investigated subsequently.Results: We found that enhanced glycolysis was associated with poor prognosis and metastasis in BLCA. Moreover, glycolysis had a close correlation with immune function, and enhanced glycolysis increased immune activities. In other words, glycolysis had a positive correlation with immune activities. Immune checkpoints such as IDO1, CD274, were up-regulated in high-glycolysis group as well.Conclusion: We speculated that in BLCA, elevated glycolysis enhanced immune function, which caused tumor cells to overexpress immune checkpoints to evade immune surveillance. Inhibition of glycolysis might be a promising assistant for immunotherapy in bladder cancer.  相似文献   
42.
以可在黑龙江地区露地越冬的5个现代月季(Rosa chinensis)品种为实验材料,分别以其无菌苗的叶片和茎段为外植体,研究了愈伤组织诱导及植株再生方法。实验结果表明:5个寒地月季品种的叶片和茎段均可诱导出愈伤组织,2,4-D诱导愈伤组织的效果较好,高浓度的细胞分裂素不适合用于月季叶片和茎段愈伤组织的诱导;TDZ在月季愈伤组织分化培养过程中具有重要作用,光照培养可促进月季愈伤组织的分化,愈伤组织的分化能力随着继代次数的增加呈下降趋势。该实验成功地从2004-8和2004-9(2个月季品种)愈伤组织中诱导出再生植株,其愈伤组织的分化率分别为45%和38%。  相似文献   
43.
在基因治疗中,造血干细胞因为具有自我更新及分化为各种血细胞系的能力而成为一种很有吸引力的靶细胞。将外源目的基因导入造血干细胞,以纠正或补偿因基因缺陷和异常引起的疾病,特别是血液疾病已取得重要进展,例如:腺苷脱氨酶缺陷病、血友病、地中海贫血症及镰状细胞性贫血症等。而慢病毒以其转染效率高,能够感染非分裂期细胞的特点成为转染造血干细胞的最适合载体,本文就造血干细胞的特性、载体的选择及临床应用和基因治疗的安全性等方面作一综述。  相似文献   
44.

Background

Gene therapy has been used to treat a variety of health problems, but transfection inefficiency and the lack of safe vectors have limited clinical progress. Fabrication of a vector that is safe and has high transfection efficiency is crucial for the development of successful gene therapy. The present study aimed to synthesize chitosan‐alginate nanoparticles that can be used as carriers of the pAcGFP1‐C1 plasmid and to use these nanoparticles with an ultrasound protocol to achieve high efficiency gene transfection.

Methods

Chitosan was complexed with alginate and the pAcGFP1‐C1 plasmid at different charge ratios to create chitosan‐alginate‐DNA nanoparticles (CADNs). The average particle size and loading efficiency were measured. Plasmid DNA retardation and integrity were analysed on 1% agarose gels. The effect of CADNs and ultrasound on the efficiency of transfection of cells and subcutaneous tumors was evaluated.

Results

In the CADNs, the average size of incorporated plasmid DNA was 600–650 nm and the loading efficiency was greater than 90%. On the basis of the results of the plasmid DNA protection test, CADNs could protect the transgene from DNase I degradation. The transgene product expression could be enhanced efficiently if cells or tumor tissues were first given CADNs and then treated with ultrasound.

Conclusions

The use of CADNs combined with an ultrasound regimen is a promising method for safe and effective gene therapy. Copyright © 2009 John Wiley & Sons, Ltd.
  相似文献   
45.
Phosphorus is a macronutrient that is essential for plant survival. Most land plants have evolved the ability to form a mutualistic symbiosis with arbuscular mycorrhizal (AM) fungi, which enhances phosphate (Pi) acquisition. Modulation of Pi transporter systems is the master strategy used by mycorrhizal plants to adapt to ambient Pi concentrations. However, the specific functions of PHOSPHATE TRANSPORTER 1 (PHT1) genes, which are Pi transporters that are responsive to high Pi availability, are largely unknown. Here, we report that AsPT5, an Astragalus sinicus (Chinese milk vetch) member of the PHT1 gene family, is conserved across dicotyledons and is constitutively expressed in a broad range of tissues independently of Pi supply, but is remarkably induced by indole-3-acetic acid (auxin) treatment under moderately high Pi conditions. Subcellular localization experiments indicated that AsPT5 localizes to the plasma membrane of plant cells. Using reverse genetics, we showed that AsPT5 not only mediates Pi transport and remodels root system architecture but is also essential for arbuscule formation in A. sinicus under moderately high Pi concentrations. Overall, our study provides insight into the function of AsPT5 in Pi transport, AM development and the cross-talk between Pi nutrition and auxin signalling in mycorrhizal plants.  相似文献   
46.
A novel halophilic, filamentous actinomycete, designated TRM 4064T, was isolated from a hypersaline habitat in Sichuan Province, China. Phylogenetic analysis based on an almost-complete 16S rRNA gene sequence of strain TRM 4064T showed that it was most closely related to Actinopolyspora mortivallis (99.1 % sequence similarity). The sequence similarities between strain TRM 4064T and other Actinopolyspora species with validly-published names were <97.0 %. However, it had relatively low mean values for DNA–DNA relatedness with the A. mortivallis DSM 44261T (23.2 %). Optimal growth occurred at 37 °C, pH 7.0 and in the presence of 13 % (w/v) NaCl. The whole-cell sugar pattern consists of xylose, glucose, ribose and arabinose. The predominant menaquinones are MK-10(H4) (38.2 %), MK-9(H4) (25.1 %), MK-9(H2) (28.6 %) and MK-8(H4) (7.3 %). The major fatty acids are anteiso-C17:0 (36.9 %) and iso-C17:0 (19.3 %). The diagnostic phospholipids detected were diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), phosphatidylcholine (PC), phosphatidylinositol (PI) and two unknown phospholipids. The G+C content of the genomic DNA of the type strain is 66.3 mol%. Strain TRM 4064T therefore represents a novel species of the genus Actinopolyspora, for which the name Actinopolyspora dayingensis sp. nov. is proposed. The type strain is TRM 4064T (= KCTC 19979T = CCTCC AA 2010010T).  相似文献   
47.
Preclinical and clinical investigations have shown the involvement of dysregulation of hypothalamic–pituitary–adrenal (HPA) axis in the pathogenesis of depression. Hypercortisolemia and the associated hippocampal atrophy were observed in patients with depression, which could be ameliorated by the treatment with antidepressants. Therefore, neuroprotection has been proposed to be one of the acting mechanisms of antidepressant. Previous studies in our laboratory have demonstrated the antidepressant-like activity of total glycosides of peony (TGP) in mice. This study aimed to examine the effect of TGP treatment on corticosterone-induced neurotoxicity in cultured rat pheochromocytoma (PC12) cells. Treating the cells with corticosterone at 200 μM for 48 h caused apoptotic cell death. The cytotoxicity was associated with the activation of caspase-3 activity and the decrease in the mRNA ratio of bcl-2 to bax. TPG treatment at increasing doses (1–10 mg/l) protected against the corticosterone-induced toxicity in PC12 cells in a dose-dependent manner. The cytoprotection afforded by TGP treatment was associated with the inhibition of caspase-3 activity and the up-regulation of bcl-2/bax mRNA ratio. The anti-apoptotic effect of TGP is therefore likely mediated by the suppression of the mitochondrial pathway leading to apoptosis.  相似文献   
48.
While numerous small ubiquitin‐like modifier (SUMO) conjugated substrates have been identified, very little is known about the cellular signalling mechanisms that differentially regulate substrate sumoylation. Here, we show that acetylation of SUMO E2 conjugase Ubc9 selectively downregulates the sumoylation of substrates with negatively charged amino acid‐dependent sumoylation motif (NDSM) consisting of clustered acidic residues located downstream from the core ψ‐K‐X‐E/D consensus motif, such as CBP and Elk‐1, but not substrates with core ψ‐K‐X‐E/D motif alone or SUMO‐interacting motif. Ubc9 is acetylated at residue K65 and K65 acetylation attenuates Ubc9 binding to NDSM substrates, causing a reduction in NDSM substrate sumoylation. Furthermore, Ubc9 K65 acetylation can be downregulated by hypoxia via SIRT1, and is correlated with hypoxia‐elicited modulation of sumoylation and target gene expression of CBP and Elk‐1 and cell survival. Our data suggest that Ubc9 acetylation/deacetylation serves as a dynamic switch for NDSM substrate sumoylation and we report a previously undescribed SIRT1/Ubc9 regulatory axis in the modulation of protein sumoylation and the hypoxia response.  相似文献   
49.
The role of periplasmic disulfide oxidoreductase DsbA in Shiga toxin-producing Escherichia coli O157:H7 (STEC) was investigated. Deletion of dsbA (DeltadsbA) significantly decreased cell motility and alkaline phosphatase activity in STEC. STEC DeltadsbA also showed greater sensitivity to menadione and under low pH conditions. Significant reductions in surface attachment to both biotic (HT-29 epithelial cells) and abiotic (polystyrene and polyvinyl chloride) surfaces were observed in STEC DeltadsbA. In addition, no biofilm formation was detected in STEC DeltadsbA compared to wild-type cells in glass capillary tubes under continuous flow-culture system conditions. In the nematode model Caenorhabditis elegans-killing assay, the deletion of dsbA in STEC resulted in attenuated virulence compared to wild-type cells. STEC DeltadsbA was also found to have a reduced ability to colonize the nematode gut. These results suggest that DsbA plays important roles in biofilm formation and virulence in STEC cells.  相似文献   
50.
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