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21.
目的 探究幽门螺杆菌(H.pylori)根除治疗对慢性胃炎患者肠道菌群的影响及其与血清超敏C反应蛋白(hsCRP)水平的相关性。 方法 选择2018年5月至2019年5月我院收治的87例慢性胃炎患者为研究对象,所有患者均采用枸橼酸铋钾胶囊+雷贝拉唑钠肠溶胶囊+克拉霉素片+阿莫西林克拉维酸钾片进行幽门螺杆菌根除治疗,评价所有患者治疗后临床疗效、H.pylori根除率,比较所有患者治疗前后临床症状积分,肠道肠球菌、葡萄球菌、肠杆菌、乳杆菌、双歧杆菌数量及血清hsCRP水平,采用Pearson相关分析所有患者治疗后肠道菌群数量与血清hsCRP水平的相关性。 结果 入选患者临床治疗有效率为95.40%,H.pylori根除率为90.80%。患者治疗后腹胀、嗳气、腹痛、纳差评分显著低于治疗前(均P0.05)。 结论 H.pylori根除治疗能有效改善慢性胃炎患者临床症状,提高H.pylori根除率,降低血清hsCRP水平,但会造成患者肠道菌群失调,且肠道菌群数量与血清hsCRP水平无显著相关性。 相似文献
22.
SUMMARY: The Gene Ontology (GO) is a controlled biological vocabulary that provides three structured networks of terms to describe biological processes, cellular components and molecular functions. Many databases of gene products are annotated using the GO vocabularies. We found that some GO-updating operations are not easily traceable by the current biological databases and GO browsers. Consequently, numerous annotation errors arise and are propagated throughout biological databases and GO-based high-level analyses. GOChase is a set of web-based utilities to detect and correct the errors in GO-based annotations. 相似文献
23.
Chen YM Lee TH Lee SJ Lin JZ Huang R Chou HN 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2006,844(1):134-141
Artemia assays and protein phosphatase assays are commonly used for the screening of microcystins (MCs) in algal samples instead of the standard mouse toxicity assay. However, it has been shown that their results are often biased because of the matrix effects. To eliminate the possible interferences in the algal matrices, a new solid-phase extraction (SPE) method using silica gel as a sorbent was developed and evaluated. Results show that this SPE method could not only reduce the toxicity of the Microcystis samples towards brine shrimp by 50-80% but also eliminate 90-100% of the endogenous phosphatase activity from Spirulina and Chlorella samples, thus improving the determination of microcystins in algal samples using either of the two bioanalytical methods. The application of this SPE method as an off-line cleanup for high-performance liquid chromatography (HPLC) with UV detection is also described in this study. After SPE, the HPLC chromatograms of Microcystis samples have clear baselines that have no interferences with the analyte peaks. 相似文献
24.
In the previous proteomic study of human placenta, transmembrane 7 superfamily member 1 (TM7SF1) was found enriched in lysosome compartments. TM7SF1 encodes a 399-amino acid protein with a calculated molecular mass of 45 kDa. Bioinformatic analysis of its amino acid sequence showed that it is a multipass transmembrane protein containing a potential dileucine-based lysosomal targeting signal and four putative N-glycosylation sites. By percoll-gradient centrifugation and further subfraction ways, the lysosomal solute and membrane compartments were isolated respectively. Immunoblotting analysis indicated that TM7SF1 was co-fractioned with lysosome associated membrane protein 2 (LAMP2), which was only detected in lysosomal membrane compartments whereas not detected in the solute compartments. Using specific anti-TM7SF1 antibody and double-immunofluorescence with lysosome membrane protein LAMP1 and Lyso-Tracker Red, the colocalisations of endogenous TM7SF1 with lysosome and late endosome markers were demonstrated. All of this indicated that TM7SF1 is an integral lysosome membrane protein. Rat ortholog of TM7SF1 was found to be strongly expressed in heart, liver, kidney and brain while not or low detected in other tissues. In summary, TM7SF1 was a lysosomal integral membrane protein that shows tissue-specific expression. As a G-protein-coupled receptor in lysosome membrane, TM7SF1 was predicted function as signal transduction across lysosome membrane. 相似文献
25.
Plasmid phr‐YPGHc, containing the fish growth hormone (GH) cDNA driven by a heat shock protein 70A promoter and a RUBISCO SSU 2 promoter, was transferred into the protoplast of marine microalga Nannochloropsis oculata (Droop) D. J. Hibberd by electroporation. Four transgenic clones were obtained in which the transferred phr‐YPGHc was integrated into the genome and existed stably at least until the 50th generation. When we treated these transgenic microalgae by heat shock, the heterologous fish GH was produced in the amount of 0.42 to 0.27 μg · mL?1 from the 50 mL of medium. We incubated artemia with the wildtype and transgenic N. oculata for 6 h and then fed these microalgae‐treated artemia to red‐tilapia larvae. After feeding, the growth of larvae that were fed artemia incubated with transgenic microalgae was greater (i.e., statistically significant: P < 0.05) than that of larvae that were fed artemia incubated with nontransgenic microalgae: 316% versus 104% in weight gain, and 217% versus 146% in body length increase, respectively. Therefore, the N. oculata enables production of functional GH, and we propose that it might be an excellent bioreactor material. 相似文献
26.
Identification and molecular structural prediction analysis of a toxicity determinant in the Bacillus sphaericus crystal larvicidal toxin. 总被引:3,自引:0,他引:3
Z Yuan C Rang R C Maroun V Juárez-Pérez R Frutos N Pasteur C Vendrely J F Charles C Nielsen-Leroux 《European journal of biochemistry》2001,268(9):2751-2760
The operon containing the genes encoding the subunits of the binary crystal toxin of Bacillus sphaericus strain LP1-G, BinA and BinB (41.9 kDa and 51.4 kDa, respectively), was cloned and sequenced. Purified crystals were not toxic to Culex pipiens larvae. Comparison of the amino-acid sequences of this strain (Bin4) with those of the three other known toxin types (Bin1, Bin2 and Bin3) revealed mutations at six positions, including a serine at position 93 of BinA4, whereas all other types of BinA toxin from B. sphaericus had a leucine at this position. Reciprocal site-directed mutagenesis was performed to replace this serine in BinA4 from LP1-G with a leucine and the leucine in the BinA2 protein from strain 1593 with a serine. Native and mutated genes were cloned and overexpressed. Inclusion bodies were tested on C. pipiens larvae. Unlike the native Bin4 toxin, the mutated protein was toxic, and the reciprocal mutation in Bin2 led to a significant loss of toxicity. In vitro receptor-binding studies showed similar binding behaviour for native and mutated toxins. In the absence of any experimental data on the 3D structure of these proteins, sequence analysis and secondary-structure predictions were performed. Amino acid 93 of the BinA polypeptide probably belongs to an alpha helix that is sensitive to amino-acid modifications. Position 93 may be a key element in the formation of the BinA-BinB complex responsible for the toxicity and stability of B. sphaericus Bin toxins. 相似文献
27.
28.
Hélène Rangé Christine Poitou Adrien Boillot Cécile Ciangura Sandrine Katsahian Jean-Marc Lacorte Sébastien Czernichow Olivier Meilhac Philippe Bouchard Catherine Chaussain 《PloS one》2013,8(3)
Epidemiological data indicate an association between periodontitis and obesity. The biological mechanisms of this relationship remain unclear. A cross-sectional study was conducted to evaluate the relationship between periodontitis and the common systemic inflammatory markers in 32 morbidly obese patients recruited in a Clinical Nutrition department. Periodontal condition was evaluated using pocket depth (PD) measurement, a classical clinical marker of ongoing periodontitis. Major periodontal risk factors were recorded (age, gender, diabetes and smoking status), as well as plasma levels of inflammatory markers (CRP, orosomucoid, IL-6) and adipokines (adiponectin, leptin). All patients included in the sample exhibited evidence of periodontitis, 16 of whom were diagnosed as having severe disease. Adjusted logistic regression analysis indicated that the severity of periodontitis was associated with the plasma level of orosomucoid (p<0.04) after adjustment for age, gender and smoking. Our study thus suggests that the severity of periodontitis, in morbidly obese patients, is associated with the increase of orosomucoid levels. 相似文献
29.
Population genomic analysis suggests strong influence of river network on spatial distribution of genetic variation in invasive saltcedar across the southwestern United States 下载免费PDF全文
Soo‐Rang Lee Yeong‐Seok Jo Chan‐Ho Park Jonathan M. Friedman Matthew S. Olson 《Molecular ecology》2018,27(3):636-646
Understanding the complex influences of landscape and anthropogenic elements that shape the population genetic structure of invasive species provides insight into patterns of colonization and spread. The application of landscape genomics techniques to these questions may offer detailed, previously undocumented insights into factors influencing species invasions. We investigated the spatial pattern of genetic variation and the influences of landscape factors on population similarity in an invasive riparian shrub, saltcedar (Tamarix L.) by analysing 1,997 genomewide SNP markers for 259 individuals from 25 populations collected throughout the southwestern United States. Our results revealed a broad‐scale spatial genetic differentiation of saltcedar populations between the Colorado and Rio Grande river basins and identified potential barriers to population similarity along both river systems. River pathways most strongly contributed to population similarity. In contrast, low temperature and dams likely served as barriers to population similarity. We hypothesize that large‐scale geographic patterns in genetic diversity resulted from a combination of early introductions from distinct populations, the subsequent influence of natural selection, dispersal barriers and founder effects during range expansion. 相似文献
30.
Sp1 and Sp3 regulate basal transcription of the survivin gene 总被引:1,自引:0,他引:1
Xu R Zhang P Huang J Ge S Lu J Qian G 《Biochemical and biophysical research communications》2007,356(1):286-292
Survivin, a unique member of the inhibitor of apoptosis protein family, is overexpressed in many cancers and considered to play an important role in oncogenesis. In this study, we cloned and identified the proximal 269 bp promoter of survivin gene, which exhibited strong promoter activity in HeLa cells. The TATA-less, GC-rich promoter contains 7 putative binding sites for Sp1, two of which (one at position -148 to -153, the other at position -127 to -140) are essential in regulating basal survivin promoter activity. Not only Sp1 but also Sp3 can activate the survivin promoter, which were proven by EMSA, blocking Sp1 or Sp3 using RNAi or mithramycin treatment of HeLa cells, and overexpression of Sp1 or Sp3. Our results collectively suggest that Sp1 cooperates with Sp3 to regulate survivin promoter activity. 相似文献