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91.
Gastric cancer is the fourth most prevalent malignancy worldwide and remains the second most common cause of cancer-related death globally. Understanding the molecular structure of gastric carcinogenesis might identify new diagnostic and therapeutic strategies for this disease. Thus, early detection of gastric cancer is a key measure to reduce the mortality and improve the prognosis of gastric cancer. There have recently been several reports that microRNAs (miRNAs) circulate in highly stable, cell-free forms in blood. Because serum and plasma miRNAs are relatively easy to access, circulating miRNAs also have great potential to serve as non-invasive biomarkers. Although a number of miRNAs associated with gastric cancer have been identified, the underlying mechanism of these miRNAs in tumorigenesis and tumor progression remains to be investigated. The purpose of this study is to identify the potential of serum miRNAs as biomarkers for early detection of gastric cancer patients. RNA was isolated using the High Pure miRNA Isolation Kit (Roche) following the manufacturer’s protocol. cDNA and preamplification protocols were obtained from the isolated plasma miRNAs. The BioMark? 96.96 Dynamic Array (Fluidigm Corporation) for real-time qPCR was used to simultaneously quantite the expression of 740 miRNAs. All statistical analyses were performed using the Biogazelle’s qbase PLUS 2.0 software. In this study, among 740 miRNAs that we analyzed only miR-195-5p was significantly (p < 0.05, fold changes = 13, 3) down-regulated in gastric cancer patients compared with control. We demonstrated that miR-195-5p is a novel tumor suppressor miRNA and may contribute to gastric carcinogenesis. The miRNA expression profile described in this study should contribute to future studies on the role of miRNAs in gastric cancer.  相似文献   
92.
Horizontal gene transfer (HGT) is common between prokaryotes and phagotrophic eukaryotes. In metazoans, the scale and significance of HGT remains largely unexplored but is usually linked to a close association with parasites and endosymbionts. Marine sponges (Porifera), which host many microorganisms in their tissues and lack an isolated germ line, are potential carriers of genes transferred from prokaryotes. In this study, we identified a number of potential horizontally transferred genes within the genome of the sponge, Amphimedon queenslandica. We further identified homologs of some of these genes in other sponges. The transferred genes, most of which possess catalytic activity for carbohydrate or protein metabolism, have assimilated host genome characteristics and are actively expressed. The diversity of functions contributed by the horizontally transferred genes is likely an important factor in the adaptation and evolution of A. queenslandica. These findings highlight the potential importance of HGT on the success of sponges in diverse ecological niches.  相似文献   
93.
Journal of Plant Growth Regulation - Heavy metal pollution, which is one of the most important environmental problems, has a significant effect on plant growth and development. Plants influence all...  相似文献   
94.

Introduction

Endometrial cancer (EC) is associated with metabolic disturbances including obesity, diabetes and metabolic syndrome. Identifying metabolite biomarkers for EC detection has a crucial role in reducing morbidity and mortality.

Objective

To determine whether metabolomic based biomarkers can detect EC overall and early-stage EC.

Methods

We performed NMR and mass spectrometry based metabolomic analyses of serum in EC cases versus controls. A total of 46 early-stage (FIGO stages I–II) and 10 late-stage (FIGO stages III–IV) EC cases constituted the study group. A total of 60 unaffected control samples were used. Patients and controls were divided randomly into a discovery group (n?=?69) and an independent validation group (n?=?47). Predictive algorithms based on biomarkers and demographic characteristics were generated using logistic regression analysis.

Results

A total of 181 metabolites were evaluated. Extensive changes in metabolite levels were noted in the EC versus the control group. The combination of C14:2, phosphatidylcholine with acyl-alkyl residue sum C38:1 (PCae C38:1) and 3-hydroxybutyric acid had an area under the receiver operating characteristics curve (AUC) (95% CI)?=?0.826 (0.706–0.946) and a sensitivity?=?82.6%, and specificity?=?70.8% for EC overall. For early EC prediction: BMI, C14:2 and PC ae C40:1 had an AUC (95% CI)?=?0.819 (0.689–0.95) and a sensitivity?=?72.2% and specificity?=?79.2% in the validation group.

Conclusions

EC is characterized by significant perturbations in important cellular metabolites. Metabolites accurately detected early-stage EC cases and EC overall which could lead to the development of non-invasive biomarkers for earlier detection of EC and for monitoring disease recurrence.
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95.
In this study, three substituted polyhalogenated nitrobutadiene derivatives were synthesized. Compound 1‐[(2,3‐dibromopropyl)sulfanyl]‐1,3,4,4‐tetrachloro‐2‐nitrobuta‐1,3‐diene ( 4 ) was synthesized before by our group. Compounds 8‐{[1‐[(2,3‐dibromopropyl)sulfany]‐3,4,4‐trichloro‐2‐nitrobuta‐1,3‐butadien‐1‐yl}‐1,4‐dioxa‐8‐azaspiro[4.5]decane ( 5 ) and 1‐[(2,3‐dibromopropyl)sulfanyl]‐3,4,4‐trichloro‐N‐(4‐methylpiperazin‐1‐yl)‐2‐nitrobuta‐1,3‐diene‐1‐amine ( 6 ) were synthesized in this work as original compounds. Xanthine oxidase, elastase inhibition abilities, and antioxidant activities were investigated in this work for compounds 4 , 5 , and 6 . In this study, compounds 4 , 5 , and 6 exhibited antixanthine oxidase, antielastase, and antioxidant activities. Among the compounds screened, compound 4 exhibited xanthine oxidase and elastase inhibitor effect similar to the standard compound. Among the three tested compounds, compound 6 showed potent DPPH radical scavenging and reducing power activities. Therefore, these three compounds ( 4 , 5 , and 6 ) may be useful as an antixanthine oxidase, antielastase, and antioxidant agent in pharmaceutical and cosmetic industry.  相似文献   
96.
Saline and hypersaline environments make up the largest ecosystem on earth and the organisms living in such water-restricted environments have developed unique ways to cope with high salinity. As such these organisms not only carry significant industrial potential in a world where freshwater supplies are rapidly diminishing, but they also shed light upon the origins and extremes of life. One largely overlooked and potentially important feature of many salt-loving organisms is their ability to produce fructans, fructose polymers widely found in various mesophilic Eubacteria and plants, with potential functions as storage carbohydrates, aiding stress tolerance, and acting as virulence factors or signaling molecules. Intriguingly, within the whole archaeal domain of life, Archaea possessing putative fructan biosynthetic enzymes were found to belong to the extremely halophilic class of Halobacteria only, indicating a strong, yet unexplored link between the fructan syndrome and salinity. In fact, this link may indeed lead to novel strategies in fighting the global salinization problem. Hence this review explores the unknown world of fructanogenic salt-loving organisms, where water scarcity is the main stress factor for life. Within this scope, prokaryotes and plants of the saline world are discussed in detail, with special emphasis on their salt adaptation mechanisms, the potential roles of fructans and fructosyltransferase enzymes in adaptation and survival as well as future aspects for all fructanogenic salt-loving domains of life.  相似文献   
97.

Fructans, homopolymers of fructose produced by fructosyltransferases (FTs), are emerging as intriguing components in halophiles since they are thought to be associated with osmotic stress tolerance and overall fitness of microorganisms and plants under high-salinity conditions. Here, we report on the full characterization of the first halophilic FT, a levansucrase from Halomonas smyrnensis AAD6T (HsLsc; EC 2.4.1.10). The encoding gene (lsc) was cloned into a vector with a 6xHis Tag at its C-terminus, then expressed in Escherichia coli. The purified recombinant enzyme (47.3 kDa) produces levan and a wide variety of fructooligosaccharides from sucrose, but only in the presence of high salt concentrations (> 1.5 M NaCl). HsLsc showed Hill kinetics and pH and temperature optima of 5.9 and 37 °C, respectively. Interestingly, HsLsc was still very active at salt concentrations close to saturation (4.5 M NaCl) and was selectively inhibited by divalent cations. The enzyme showed high potential in producing novel saccharides derived from raffinose as both fructosyl donor and acceptor and cellobiose, lactose, galactose, and ʟ-arabinose as fructosyl acceptors. With its unique biochemical characteristics, HsLsc is an important enzyme for future research and potential industrial applications in a world faced with drought and diminishing freshwater supplies.

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98.
Cutaneous leishmaniasis has various outcomes, ranging from self-healing reddened papules to extensive open ulcerations that metastasise to secondary sites and are often resistant to standard therapies. In the case of L. guyanensis (L.g), about 5–10% of all infections result in metastatic complications. We recently showed that a cytoplasmic virus within L.g parasites (LRV1) is able to act as a potent innate immunogen, worsening disease outcome in a murine model. In this study, we investigated the immunophenotype of human patients infected by L.g and found a significant association between the inflammatory cytokine IL-17A, the presence of LRV1 and disease chronicity. Further, IL-17A was inversely correlated to the protective cytokine IFN-γ. These findings were experimentally corroborated in our murine model, where IL-17A produced in LRV1+ L.g infection contributed to parasite virulence and dissemination in the absence of IFN-γ. Additionally, IL-17A inhibition in mice using digoxin or SR1001, showed therapeutic promise in limiting parasite virulence. Thus, this murine model of LRV1-dependent infectious metastasis validated markers of disease chronicity in humans and elucidated the immunologic mechanism for the dissemination of Leishmania parasites to secondary sites. Moreover, it confirms the prognostic value of LRV1 and IL-17A detection to prevent metastatic leishmaniasis in human patients.  相似文献   
99.
Increases in the risk of infections and malignancy due to immune suppressive therapies of inflammatory bowel diseases (IBDs) have led the researchers to focus on more nontoxic and acceptable natural products like curcumin. Here we investigate whether prophylactic and therapeutic application of the curcumin alters the enzyme activities of paraoxonase (PON), carbonic anhydrase (CA), glucose-6-phosphate dehydrogenase (G6PD) and cytosolic β-glucosidase in dextran sulphate sodium (DSS)-induced ulcerative colitis mice. Prophylactic application of curcumin resulted in higher MPO activity, less body weight loss and longer colon lengths compared to therapeutic group indicating preventive role of curcumin in IBDs. DSS-induced decrease in liver and serum PON activities were completely recovered by prophylactic administration of curcumin. DSS-induced reduction in liver cytosolic β-glucosidase activity was not affected by curcumin neither in the prophylactic group nor in the therapeutic group. Erythrocyte CA activity was significantly increased in curcumin groups, however no remarkable change in G6PD activity was observed.  相似文献   
100.
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