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This study was conducted to determine effects of dietary supplementation with 1 % l-glutamine for 14 days on the abundance of intestinal bacteria and the activation of intestinal innate immunity in mice. The measured variables included (1) the abundance of Bacteroidetes, Firmicutes, Lactobacillus, Streptococcus and Bifidobacterium in the lumen of the small intestine; (2) the expression of toll-like receptors (TLRs), pro-inflammatory cytokines, and antibacterial substances secreted by Paneth cells and goblet cells in the jejunum, ileum and colon; and (3) the activation of TLR4-nuclear factor kappa B (NF-κB), mitogen-activated protein kinases (MAPK), and phosphoinositide-3-kinases (PI3K)/PI3K-protein kinase B (Akt) signaling pathways in the jejunum and ileum. In the jejunum, glutamine supplementation decreased the abundance of Firmicutes, while increased mRNA levels for antibacterial substances in association with the activation of NF-κB and PI3K-Akt pathways. In the ileum, glutamine supplementation induced a shift in the Firmicutes:Bacteroidetes ratio in favor of Bacteroidetes, and enhanced mRNA levels for Tlr4, pro-inflammatory cytokines, and antibacterial substances participating in NF-κB and JNK signaling pathways. These results indicate that the effects of glutamine on the intestine vary with its segments and compartments. Collectively, dietary glutamine supplementation of mice beneficially alters intestinal bacterial community and activates the innate immunity in the small intestine through NF-κB, MAPK and PI3K-Akt signaling pathways.  相似文献   

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Ralstonia paucula strain RA4T, a gram negative, non-spore forming, motile bacterium having positive catalase and oxidase test, was isolated from surface soil. Twin arginine translocation protein type D (TatD) is shown to be located in cytoplasm and exhibits magnesium-dependent DNase. A tatD DNase gene was isolated and cloned from Ralstonia paucula RA4T genome. Nucleotide sequence analysis of the gene revealed 813 nucleotides encoding a protein of 270 amino acid residues. The tatD gene showed a high similarity to homolog gene from Ralstonia pickettii strain 12D. The deduced polypeptide sequence of TatD DNase from R. paucula RA4T had a typical catalytic site, HHPLDEHRHDP, and its calculated molecular mass and predicted isoelectric point were 29616 Da and 5.33, respectively. The deduced amino acid sequence showed a high degree of similarity to TatD DNase isoforms from Ralstonia genus and other sources. Predicted three-dimensional structure of TatD confirmed the presence of active site and theoretical function as DNase.  相似文献   

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N-myc downstream-regulated gene 1 (NDRG1) has been proposed as a tumor suppressor gene in many different types of tumors, but its potential function and corresponding mechanism are not yet fully elucidated. This study aims to detect the possible function of NDRG1 in gastric cancer progression. In this study, 112 paired gastric cancer tissues and corresponding nonmalignant gastric tissues were utilized to identify the differential protein expression of NDRG1 by immunohistochemistry and its clinical significance was analyzed. Furthermore, 49 of 112 paired gastric specimens were used to detect the differential mRNA expression by real-time PCR. The over expression of NDRG1 in human gastric cancer cell line AGS by PcDNA3.1–NDRG1 transfection was utilized to detect the role of NDRG1 in regulating the biological behavior of gastric cancer. NDRG1 expression was significantly decreased in primary gastric cancer tissues, compared with its corresponding nonmalignant gastric tissues (p < 0.05), and its decreased expression was significantly associated with lymph node metastasis (p < 0.01), invasion depth (p < 0.01) and differentiation (p < 0.05). Additionally, the overall survival rate of gastric cancer patients with high expression of NDRG1 was higher than those with low expression during the follow-up period. NDRG1 overexpression suppressed cells proliferation, invasion and induced a G1 cell cycle arrest in gastric cancer. Furthermore, the down-regulation of NDRG1 in gastric cancer metastatic progression was correlated to E-cadherin and MMP-9. Our results verify that NDRG1 acts as a tumor suppressor gene and may play an important role in the metastasis progression and prognosis of gastric cancer.  相似文献   

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Transgenic tobacco plants expressing Arabidopsis thaliana ARGOS and ARGOS-LIKE genes under the control of the chalcone synthase promoter of Petunia hybrida L., as well as the estradiol inducible XVE system, have been obtained. The part of transgenic plants with flower-specific expression of the target genes was characterized by increased flower size, caused by an increase in cell size and quantity in the case of the ARGOS gene and by a stimulation of cell growth via stretching in the case of the ARGOS-LIKE gene. An enhanced expression level of the NtEXPA1, NtEXPA4 genes encoding expansins, NtEXGT gene encoding endo-xyloglucan transferase, and the AINTEGUMENTA-like gene was detected in the flowers of transgenic tobacco plants. In the case of inducible expression of ARGOS and ARGOS-LIKE genes, an increase in leaf, stem and flower size was revealed in several lines of transgenic plants as compared to control. Expression of the ARGOS gene also affected cell number and size in this case, while the ARGOS-LIKE gene mainly influenced cell size via stretching. Inducible expression of the ARGOS gene in flowers mainly provided an enhanced containment of AINTEGUMENTA-like mRNA, while ARGOS-LIKE gene expression resulted in the activation of NtEXPA1 and NtEXGT genes.  相似文献   

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The genetic factors of cancer predisposition remain elusive in the majority of familial and/or early-onset cases of breast cancer (BC). This type of BC is promoted by germ-line mutations that inactivate BRCA1 or BRCA2. On the other hand, recent studies have indicated that alterations in the levels of miRNA expression are linked to this disease. Although BRCA1 and BRCA2 gene mutations have been reported to commonly lead to alterations in genes that encode cancer-related proteins, little is known regarding the putative impact of these mutations on noncoding miRNAs. In the present study, we aimed to determine whether miRNA dysregulation is involved in the pathogenesis of BRCA-mutated BC. An expression analysis of 14 human miRNAs previously shown to be related to BC diagnosis, prognosis, and drug resistance was conducted using tissues from 60 familial and/or early-onset patients whose peripheral blood samples had been screened for BRCA1 and BRCA2 mutations through sequence analysis. Let-7a and miR-335 expression levels were significantly downregulated in the tumors of patients with a BRCA mutation compared with those of patients without a BRCA mutation (P = 0.04 and P = 0.02, respectively). Our results defined the associations between the expression status of let-7a and miR-335 and BRCA mutations. The expression analysis of these miRNAs might be used as biomarkers of the BRCA mutation status of early-onset and/or familial BC.  相似文献   

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Thebcr-abl chimeric gene of Philadelphia chromosome positive chronic myelogenous leukemias is only weakly transforming. This transformation activity is greatly enhanced by a Lys-for-Glu substitution at position 832 in the c-abl gene, as occurs in the highly transforming v-abl genes. It has been suggested that this mutation results in a significant structural change in the encoded protein product. Using conformational energy analysis, we have determined the allowed low-energy conformations for residues 828–836 of this protein with Lys and Glu at position 832. In both cases, the overwhelmingly preferred conformation for this region is a bend-helix motif. The helix terminates at residue 836, and there are no discernible differences in conformation between the Lys- and Glu-containing sequences. These results suggest that the activating amino acid substitution at position 832 in the c-abl protein product does not produce its effect via a local conformational change.  相似文献   

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Hepatocellular carcinoma (HCC) is a very aggressive neoplasia requiring early and accurate diagnosis to improve patient outcomes with timely treatment. The liver is also very frequently colonized by metastases, and the most frequent differential diagnosis is HCC against intrahepatic cholangiocarcinoma or metastatic adenocarcinoma. Metabolomics is a powerful tool for identification of altered biomarkers in cancer, and to evaluate the efficacy of drug treatments. Here we analyzed by HILIC-MS/MS methylated arginines, basic amino acids (Arg, Cit, Orn), and their ratios in the extracts of primary HCC tissues, liver metastases from colorectal carcinoma (MET), cirrhotic related hepatitis-C-virus (CIR), and non-cirrhotic normal liver (NT) adjacent tissues. We found high levels of Arg (p < 0.0001) and Arg/Orn (p < 0.01) in MET compared to other tissues. In MET, compared to NT and CIR, Arg concentration was fivefold higher, while in HCC it was twofold higher. ADMA increased twofold compared to NT and CIR, while in HCC it was 50 % higher. Arg/Cit and ADMA/SDMA ratios were significantly higher in MET compared to NT and CIR (p < 0.005). Arg/Orn, Arg/Cit, and ADMA/SDMA ratios increased progressively from NT, CIR, HCC, to MET tissues. Arg/Cit correlated significantly with Arg/Orn ratios (r = 0.77; p < 0.0001), and discriminates tumor from non-tumor samples. In addition, the discriminant lactate/glucose ratio we previously found by NMR, also correlated significantly with the Arg levels (r = 0.64; p < 0.0001), and discriminated MET from all other tissues. The results indicated that Arg in MET is higher than other tissue classes, suggesting that, together with the lactate/glucose ratio, it can be considered a further biomarker for HCC-metastases differentiation.  相似文献   

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A previous investigation showed that deep-sea water (DSW) can affect the expression of genes that regulate metastasis, including cyclooxygenase-2 (COX-2), matrix metalloproteinase-2 (MMP-2), urokinase plasminogen activator (uPA) and uPA receptor (uPAR), in HT-29 human colorectal adenocarcinomas. In the present study, we investigated the effects of DSW on inducible nitric oxide synthase (iNOS) expression and cell migration and also explored the mechanism of DSW-induced anti-metastatic potential in HT-29 human colorectal adenocarcinomas. Cytokine-induced expression of iNOS, which is highly expressed in colon cancer and enhances cancer growth and metastasis, was decreased in a hardness-dependent manner by DSW. Also, the wound healing assay revealed that DSW inhibited 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced cell migration in a hardness-dependent manner. DSW also decreased the phosphorylation of various MAPKs, including p38, ERK and JNK, and suppressed the nuclear translocation of NF-κB but not c-Jun. The results suggest that DSW may inhibit cancer cell growth related to iNOS overexpression and PKC-mediated cell migration in HT-29 human colorectal adenocarcinomas and the antimetastatic potential of DSW may be regulated by prevention of NF-κB nuclear translocation via inhibition of p38, ERK and JNK phosphorylation. In conclusion, the present investigation demonstrates that DSW inhibits cancer growth and metastasis via down-regulation of iNOS expression and the MAPK/NF-κB signaling pathway.  相似文献   

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The aim of the study was to successfully construct three plasmids, which include the GALV.fus gene plasmid regulated by the herpes simplex virus type 1 (HSV-1) late expression gene-UL38 promoter and induced by HSV-1 (HSV-UL38P-GALV.fus), the cytomegalovirus promoter without tumor specificity (CMVP) GALV.fus plasmid (HSV-CMVP-GALV.fus), and the control plasmid in which the GALV.fus gene fragment was replaced by the enhanced green fluorescent protein (EGFP) gene fragment (HSV-CMVP-EGFP). The three constructed plasmids were all packaged and named as Synco-2, Synco-1, and Baco-1. The plasmids were amplified in coliform bacterium and transfected into Vero cells using lipofectamine. These recombinant HSV-1 were amplified in Vero cells and purified by conventional methods of cesium chloride, TCID50 method is used to measure virus titers. The total RNA was then extracted from the HepG2 cells transfected by Synco-1 and Synco-2, and the expression of GALV.fus mRNA was detected by RT-PCR. The three recombinant HSV-1 vectors were propagated in Vero cells and purified by cesium chloride density gradient centrifugation, titrated by TCID50 method, and packaged. The titers of Baco-1, Synco-1, and Synco-2 were 3 × 1010, 1 × 1011, and 4 × 1010 pfu/ml. The GALV.fus gene was identified in the infected HepG2 cells by RT-PCR method.  相似文献   

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Six Arcanobacterium haemolyticum strains isolated from six patients of two hospitals in Denmark were identified phenotypically, also including matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis, and by genotypic methods. The latter were performed by sequencing 16S rDNA and glyceraldehyde 3-phosphate dehydrogenase encoding gene gap and by amplification of an A. haemolyticum specific region of 16S–23S rDNA intergenic spacer region and 23S rDNA. The six A. haemolyticum strains were further investigated for the presence of seven potential virulence genes encoding arcanolysin, phospholipase D, hemolysin A, CAMP factor family protein, collagen binding protein, neuraminidase A and neuraminidase H which appeared to be present in two (seven virulence genes), two (six virulence genes) and two strains (four virulence genes), respectively. The phenotypic and genotypic properties described in the present study might help to reliably identify and further characterize A. haemolyticum isolated from human patients, a species which seems to be of increasing importance.  相似文献   

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The mahseers are an important group of fishes endemic to Asia with most species considered threatened. Conservation plans to save declining wild populations are hindered by unstable taxonomy, and detailed systematic review could form a solid platform for future management and conservation. D-loop and cytochrome c oxidase I (COI) mtDNA sequences were examined in nine mahseer species of Tor, Neolissochilus, and Naziritor. Pseudogenes amplified in a portion of the species limited the utility of the D-loop region. ABGD analysis, NJ, ML, and MP methods and genetic distance (TrN?+?I?+?G) using COI data revealed concordant species delimiting patterns. The three genera were monophyletic, separated as distinct clades (TrN?+?I?+?G 0.064 to 0.106), and Naziritor was flagged as a separate genus, distinct from Puntius (TrN?+?I?+?G 0.196). Out of seven nominal species known for Tor cogeners from India, only five were recovered with mtDNA data (TrN?+?I?+?G 0.000 to 0.037) and two species could not be distinguished with the molecular data set employed. Tor mosal, synonymized as Tor putitora, was rediscovered as a distinct species (TrN?+?I?+?G 0.031) based on its type locality. Tor mussulah was confirmed as a separate species (TrN?+?I?+?G 0.019 to 0.026). Two valid species, Tor macrolepis and T. mosal mahanadicus, were not distinct from T. putitora (TrN?+?I?+?G 0.00). The high divergence with mtDNA data failed to validate T. mosal mahanadicus as a subspecies of T. mosal (TrN?+?I?+?G 0.031). Morphological outliers discovered within the distribution range of Tor tor (TrN?+?I?+?G 0.022 to 0.025) shared the same lineage with T. putitora (TrN?+?I?+?G 0.002 to 0.005), indicating a new extended distribution of the Himalayan mahseer T. putitora in the rivers of the Indian central plateau. The findings indicate the need for integrating molecular and morphological tools for taxonomic revision of the Tor and Naziritor genera, so that taxa are precisely defined for accurate in situ and ex situ conservation decisions.  相似文献   

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Cardiac fibroblasts are known to be essential for adaptive responses in the pathogenesis of cardiovascular diseases, and increased intercellular communication of myocardial cells and cardiac fibroblasts acts as a crucial factor in maintaining the functional integrity of the heart. AMP-activated kinase (AMPK) is a key stress signaling kinase, which plays an important role in promoting cell survival and improving cell function. However, the underlying link between AMPK and gap junctional communication (GJIC) is still poorly understood. In this study, a connection between AMPK and GJIC in high glucose-mediated neonatal cardiac fibroblasts was assessed using fibroblast migration, measurement of dye transfer and connexin43 (Cx43) expression. 5-aminoimidazole-4-carboxamide-1-β-D-ribofuranoside (AICAR) and Compound C (CC) were used to regulate AMPK activity. The levels of cell migration and Cx43 protein expression in neonatal cardiac fibroblasts increased during high glucose treatment, accompanied by developed dye transfer. In addition, high glucose induced abundant phosphorylation of AMPK. Suppression of AMPK phosphorylation using CC reduced dye transfer, cell migration and Cx43 protein expression in neonatal cardiac fibroblasts, whereas the activation of AMPK using AICAR mimicked the high glucose-mediated cell migration, Cx43 protein expression and dye transfer enhancement. AMPK appears to participate in regulating GJIC in high-glucose-treated neonatal cardiac fibroblasts, including cell migration, dye transfer, Cx43 expression and distribution.  相似文献   

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Here, we present a simple method for controlling the density of Au nanoparticles (Au NPs) on a modified silicon substrate, by destabilizing the colloidal Au NPs with 3-mercaptopropyltrimethoxylsilane (3-MPTMS) for microelectromechanical-system-based applications to reduce tribological issues. A silicon surface was pretreated with a 3-MPTMS solution, immediately after which thiolated Au NPs were added to it, resulting in their uniform deposition on the silicon substrate. Without any material property change of the colloidal Au NPs, we observed the formation of large clusters Au NPs on the modified silicon surface. Analysis by scanning electron microscopy with energy dispersive X-ray spectroscopy indicated that the addition of 3-MPTMS resulted in an alternation of the chemical characteristics of the solution. Atomic force microscopy imaging supported the notion that silicon surface modification is the most important factor on tribological properties of materials along with ligand-modified Au NPs. The density of Au NPs on a silicon surface was significantly dependent on several factors, including the concentration of colloidal Au NPs, deposition time, and concentration of 3-MPTMS solution, while temperature range which was used throughout experiment was determined to have no significant effect. A relatively high density of Au NPs forms on the silicon surface as the concentrations of Au NPs and 3-MPTMS are increased. In addition, the maximum deposition of Au NPs on silicon wafer was observed at 3 h, while the effects of temperature variation were minimal.  相似文献   

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