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131.
Colorectal cancer is one of the most common and leading malignancies globally. Long noncoding RNAs (lncRNAs) function as potentially critical regulator in colorectal cancer. LINC01234, a novel lncRNA in tumor biology, regulates the progression of various tumors. However, the tumorigenic mechanism of LINC01234 in colorectal cancer is still unclear. This study was performed with the aim to prospectively investigate clinical significance, effect, and mechanism of lncRNA LINC01234 in colorectal cancer. First, we found that LINC01234, localized in the cytoplasm, was increased in both colorectal cancer cell lines and tissues. Subsequent functional assays suggested LINC01234 knockdown suppressed cell proliferation, migration, and invasion of colorectal cancer cells, while blocked cell cycle and induced cell apoptosis. Moreover, we identified that miR-1284 was target of LINC01234, we further demonstrated a negative correlation with LINC01234 in colorectal cancer tissues and cells. Furthermore, miR-1284 targeted and suppressed tumor necrosis factor receptor–associated factor 6 (TRAF6). Loss-of-function assay revealed that LINC01234 silencing suppressed colorectal cancer progression through inhibition of miR-1284. In vivo subcutaneous xenotransplanted tumor model indicated LINC01234 knockdown inhibited in vivo tumorigenic ability of colorectal cancer via downregulation of TRAF6. Collectively, this study clarified the biological significance of LINC01234/miR-1284/TRAF6 axis in colorectal cancer progression, providing insights into LINC01234 as novel potential therapeutic target for colorectal cancer therapeutic from bench to clinic.  相似文献   
132.
The application of antibiotic treatment with assistance of metabolomic approach in axenic isolation of cyanobacterium Nostoc flagelliforme was investigated. Seven antibiotics were tested at 1–100 mg L?1, and order of tolerance of N. flagelliforme cells was obtained as kanamycin > ampicillin, tetracycline > chloromycetin, gentamicin > spectinomycin > streptomycin. Four antibiotics were selected based on differences in antibiotic sensitivity of N. flagelliforme and associated bacteria, and their effects on N. flagelliforme cells including the changes of metabolic activity with antibiotics and the metabolic recovery after removal were assessed by a metabolomic approach based on gas chromatography–mass spectrometry combined with multivariate analysis. The results showed that antibiotic treatment had affected cell metabolism as antibiotics treated cells were metabolically distinct from control cells, but the metabolic activity would be recovered via eliminating antibiotics and the sequence of metabolic recovery time needed was spectinomycin, gentamicin > ampicillin > kanamycin. The procedures of antibiotic treatment have been accordingly optimized as a consecutive treatment starting with spectinomycin, then gentamicin, ampicillin and lastly kanamycin, and proved to be highly effective in eliminating the bacteria as examined by agar plating method and light microscope examination. Our work presented a strategy to obtain axenic culture of N. flagelliforme and provided a method for evaluating and optimizing cyanobacteria purification process through diagnosing target species cellular state.  相似文献   
133.
随着转基因技术在植物中的广泛应用,转基因沉默受到越来越多的重视。转基因沉默可发生在转录和转录后两种水平,其基本特征就是依赖于同源的重复序列。转基因的重复拷贝间,转基因与同源的内源基因间及RNA病毒与同源转基因间都会发生基因沉默。可能有不同的机制导致转基因沉默,本文综述了转基因沉默的机理研究及转基因沉默在植物抗病基因工程和植物功能基因组学方面的应用 。  相似文献   
134.
Probiotics and Antimicrobial Proteins - This study aimed to elucidate the targets and mechanisms of anti-staphylococcal effects from bioactive metabolites produced by lactic acid bacteria. We aimed...  相似文献   
135.
陈世雄  丁文柏 《蛇志》1999,11(1):23-24
目的寻求治疗结核包囊性胸腔积液的新方法。方法胸膜活检确诊为结核性胸腔积液并经B超或胸部X线证实有粘连包囊的病人15例,经胸腔内注入尿激酶每次10万单位,用60ml生理盐水稀释,每8~12h重复,连续5次,每次记录抽取胸水总量,并复查B超观察粘连包囊情况。对照组为单纯用抗结核治疗及间断抽胸水15例。结果实验组13例有效,总有效率86.7%。对照组2例有效,有效率13.3%,疗效明显优于对照组(P<0.05)。结论尿激酶胸腔内注入是治疗结核性粘连包囊性胸腔积液的一种安全可靠的新方法。  相似文献   
136.
Salinity is one of the major obstacles in the agriculture industry causing huge losses in productivity. Several strategies such as plant growth regulators with arbuscular mycorrhizal fungi (AMF) have been used to decrease the negative effects of salt stress. In our experiment, 28‐homobrassinolide (HBL) with spraying intervals was combined with AMF (Glomus versiforme) in cucumber cultivars Jinyou 1# (salt sensitive) and (Changchun mici, in short, CCMC, salt tolerant) under NaCl (100 mmol/L). Studies have documented that the foliar application of HBL and AMF colonization can enhance tolerance to plants under stress conditions. However, the mechanism of the HBL spraying intervals after 15 and 30 days in combination with AMF in cucumber under salt stress is still unknown. Our results revealed that the HBL spraying interval after 15 days in combination with AMF resulted in improved growth, photosynthesis, and decreased sodium toxicity under NaCl. Moreover, the antioxidant enzymes SOD (superoxide dismutase; EC 1.15.1.1) and POD activity (peroxidase; EC 1.11.1.7) showed a gradual increase after every 10 days, while the CAT (catalase; EC 1.11.1.6) increased after 30 days of salt treatments in both cultivars. This research suggests that the enhanced tolerance to salinity was mainly related to elevated levels of antioxidant enzymes and lower uptake of Na+, which lowers the risk of ion toxicity and decreases cell membrane damage.  相似文献   
137.
High levels of SOX4 expression have been found in a variety of human cancers, such as lung, brain and breast cancers. However, the expression of SOX4 in gastric tissues remains unknown. The SOX4 expression was detected using immunohistochemical staining and semi-quantitative RT-PCR, and our results showed that SOX4 was up-regulated in gastric cancer compared to benign gastric tissues. To further elucidate the molecular mechanisms underlying up-regulation of SOX4 in gastric cancers, we analyzed the expression of microRNA-129-2 (miR-129-2) gene, the epigenetic repression of which leads to overexpression of SOX4 in endometrial cancer. We found that up-regulation of SOX4 was inversely associated with the epigenetic silencing of miR-129-2 in gastric cancer, and restoration of miR-129-2 down-regulated SOX4 expression. We also found that inactivation of SOX4 by siRNA and restoration of miR-129-2 induced apoptosis in gastric cancer cells.  相似文献   
138.
The role of coastal mangrove wetlands in sequestering atmospheric carbon dioxide (CO2) and mitigating climate change has received increasing attention in recent years. While recent studies have shown that methane (CH4) emissions can potentially offset the carbon burial rates in low‐salinity coastal wetlands, there is hitherto a paucity of direct and year‐round measurements of ecosystem‐scale CH4 flux (FCH4) from mangrove ecosystems. In this study, we examined the temporal variations and biophysical drivers of ecosystem‐scale FCH4 in a subtropical estuarine mangrove wetland based on 3 years of eddy covariance measurements. Our results showed that daily mangrove FCH4 reached a peak of over 0.1 g CH4‐C m?2 day?1 during the summertime owing to a combination of high temperature and low salinity, while the wintertime FCH4 was negligible. In this mangrove, the mean annual CH4 emission was 11.7 ± 0.4 g CH4‐C m–2 year?1 while the annual net ecosystem CO2 exchange ranged between ?891 and ?690 g CO2‐C m?2 year?1, indicating a net cooling effect on climate over decadal to centurial timescales. Meanwhile, we showed that mangrove FCH4 could offset the negative radiative forcing caused by CO2 uptake by 52% and 24% over a time horizon of 20 and 100 years, respectively, based on the corresponding sustained‐flux global warming potentials. Moreover, we found that 87% and 69% of the total variance of daily FCH4 could be explained by the random forest machine learning algorithm and traditional linear regression model, respectively, with soil temperature and salinity being the most dominant controls. This study was the first of its kind to characterize ecosystem‐scale FCH4 in a mangrove wetland with long‐term eddy covariance measurements. Our findings implied that future environmental changes such as climate warming and increasing river discharge might increase CH4 emissions and hence reduce the net radiative cooling effect of estuarine mangrove forests.  相似文献   
139.
myo-Inositol monophosphate phosphatase (IMPase) has been purified 888-fold to apparent homogeneity from procine brains. The purification procedure involves: homogenization, ammonium sulfate fractionation, and a number of ion-exchange and gel-filtration chromatography steps. The purified enzyme exhibited a final specific activity of 932 nmol . min(-1) . mg(-1). The molecular mass of the enzyme was estimated to be 29kDa by SDS poly-acrylamide gel electrophoresis and 58 +/- 5 kDa by HPLC gel filtration in 10mM Tris-HCI, pH 7.4. Kinetic measurements have shown that the apparent K(m) value of the phosphatase for the utilization of inositol-1-phosphate and beta-glycerol phosphate are 3.20 x 10(-4) and 8 x 10(-3) M, respectively. Similar to the same enzyme isolated from bovine brains, the porcine brain enzyme has been shown to be inhibited by lithium. The K(1) was determined to be 6.38 x 10(-4) M and the inhibition is uncompetitive. (c) 1995 John Wiley & Sons, Inc.  相似文献   
140.
Both the Taihang Mountain area in north-central China and Chaoshan area in the southeastern littoral of China are areas with high risk of esophageal cancer (EC). Our previous study confirmed that populations from the two areas might share similar matrilineal backgrounds and found that mitochondrial DNA (mtDNA) haplogroup D, especially subhaplogroups D4a and D5a, might be genetic background markers of EC in Chaoshan area. Here, to further determine whether D4a, D5a, and D might be susceptibility markers for EC in the two high-risk areas, we performed a case–control study with larger samples and analyzed the distributions of these three haplogroups in subjects (controls [n = 898] and patients [n = 768]) from the two areas. D4a haplogroup was significantly associated with increased risk of EC in Taihang Mountain subjects, especially women. D5 haplogroup was associated with EC at the general population level in the Taihang Mountain area and in subjects ≤ 60 years, especially women ≤ 60 years, in the Chaoshan area. D haplogroup was associated with EC only in subjects ≤ 60 years, especially men ≤ 60 years, in the Chaoshan area. D4a and D5 showing positive association with EC in the Taihang Mountain area became the predominant subhaplogroups of D in Chaoshan controls. In conclusion, D, D4a, and D5 haplogroups might be susceptibility markers for EC in the two high-risk areas in China, particularly D4a and D5 for the Taihang Mountain area and D and D5 for the Chaoshan area.  相似文献   
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