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排序方式: 共有128条查询结果,搜索用时 15 毫秒
101.
102.
Lei Kong MD Qinghua Wu MD Liangchao Zhao MD Jinhua Ye MM Nengping Li MD Huali Yang 《Journal of cellular biochemistry》2019,120(12):19377-19387
The present study aimed to investigate the long noncoding RNAs (lncRNAs) and messenger RNAs (mRNAs) involved in the progression of gallbladder cancer and explore the potential physiopathologic mechanisms of gallbladder cancer in terms of competing endogenous RNAs (ceRNAs). The original lncRNA and mRNA expression profile data (nine gallbladder cancer tissues samples and nine normal gallbladder samples) in GSE76633 was downloaded from the Gene Expression Omnibus database. Differentially expressed mRNAs and lncRNAs between gallbladder cancer tissue and normal control were selected and the pathways in which they are involved were analyzed using bioinformatics analyses. MicroRNAs (miRNAs) were also predicted based on the differentially expressed mRNAs. Finally, the co-expression relation between lncRNA and mRNA was analyzed and the ceRNA network was constructed by combining the lncRNA-miRNA, miRNA-mRNA, and lncRNA-mRNA pairs. Overall, 373 significantly differentially expressed mRNAs and 47 lncRNAs were identified between cancer and normal tissue samples. The upregulated genes were significantly enriched in the extracellular matrix (ECM)-receptor interaction pathway, while the downregulated genes were involved in the complement and coagulation cascades. Altogether, 128 co-expression relations between lncRNA and mRNA were obtained. In addition, 196 miRNA-mRNA regulatory relations and 145 miRNA-lncRNA relation pairs were predicted. Finally, the lncRNA-miRNA-gene ceRNA network was constructed by combining the three types of relation pairs, such as XLOC_011309-miR-548c-3p-SPOCK1 and XLOC_012588-miR-765-CEACAM6. mRNAs and lncRNAs may be involved in gallbladder cancer progression via ECM-receptor interaction pathways and the complement and coagulation cascades. Moreover, ceRNAs such as XLOC_011309-miR-548c-3p-SPOCK1 and XLOC_012588-miR-765-CEACAM6 can also be implicated in the pathogenesis of gallbladder cancer. 相似文献
103.
Background
Patients with multiple sclerosis (MS) have a decreased frequency of CD8+ T cells reactive to their own Epstein-Barr virus (EBV) infected B cells. We have proposed that this might predispose to the development of MS by allowing EBV-infected autoreactive B cells to accumulate in the central nervous system. The decreased CD8+ T cell response to EBV results from a general CD8+ T cell deficiency and also a decreased proportion of EBV-specific T cells within the total CD8+ T cell population. Because decreased HLA class I expression on monocytes and B cells has been reported in MS and could influence the generation and effector function of EBV-specific CD8+ T cells, the present study was undertaken to measure the expression of HLA molecules on B cells and monocytes in patients with MS. 相似文献104.
105.
Eraqi R. Khannoon Birte Flachsbarth Afaf El-Gendy Krysia Mazik Jrg D. Hardege Stefan Schulz 《Biochemical Systematics and Ecology》2011,39(2):95-101
Integumental gland secretions in lizards have been postulated to play a role as semiochemicals, but few studies have analysed the chemical nature of the gland secretions used in communication. We analysed the femoral gland secretions of Acanthodactylus boskianus using GC–MS, compared secretions of both sexes and different ages of males. For the first time in reptiles monoglycerides of fatty acids and glycerol monoethers of long chain alcohols were identified. In addition, alcohols, steroids, carboxylic acids, alkanes, amides, aldehydes, carboxylic acid esters, and squalene occurred. Sexual differences and age correlation in the amount of all major groups of compounds occurred, as such these results strengthen the theory that these secretions are used as semiochemicals. This work lays the foundations to test in future the role of chemical cues in mate choice and dominance hierarchies in lizards and to test the activity of compounds in behavioural assays to eventually identify the pheromones. 相似文献
106.
Several fungal endophytes of the Egyptian marine sponge Latrunculia corticata were isolated, including strains Trichoderma sp. Merv6, Penicillium sp. Merv2 and Aspergillus sp. Merv70. These fungi exhibited high cellulase activity using different lignocellulosic substrates in solid state fermentations
(SSF). By applying mutagenesis and intergeneric protoplast fusion, we have obtained a recombinant strain (Tahrir-25) that
overproduced cellulases (exo-β-1,4-glucanase, endo-β-1,4-glucanase and β-1,4-glucosidase) that facilitated complete cellulolysis
of agricultural residues. The process parameters for cellulase production by strain Tahrir-25 were optimized in SSF. The highest
cellulase recovery from fermentation slurries was achieved with 0.2% Tween 80 as leaching agent. Enzyme production was optimized
under the following conditions: initial moisture content of 60% (v/w), inoculum size of 106 spores ml−1, average substrate particle size of 1.0 mm, mixture of sugarcane bagasse and corncob (2:1) as the carbon source supplemented
with carboxymethyl cellulose (CMC) and corn steep solids, fermentation time of 7 days, medium pH of 5.5 at 30°C. These optimized
conditions yielded 450, 191, and 225 units/gram dry substrate (U gds−1) of carboxylmethyl cellulase, filter-paperase (FPase), and β-glucosidase, respectively. Subsequent fermentation by the yeast,
Saccharomyces cerevisiae NRC2, using lignocellulose hydrolysates obtained from the optimized cellulase process produced the highest amount of ethanol
(58 g l−1). This study has revealed the potential of exploiting marine fungi for cost-effective production of cellulases for second
generation bioethanol processes. 相似文献
107.
Background
The type III secretion system (TTSS) is an important virulence determinant of Gram-negative bacterial pathogens. It enables the injection of effector proteins into the cytosol of eukaryotic cells. These effectors ultimately manipulate the cellular functions of the infected organism. Salmonella enterica serovar Typhimurium encodes two virulence associated TTSSs encoded by the Salmonella Pathogenicity Islands (SPI) 1 and 2 that are required for the intestinal and systemic phases of the infection, respectively. However, recent studies suggest that the roles of these TTSSs are not restricted to these compartments. The regulation of TTSSs in Salmonella is very complex with several regulators operating to activate or to repress expression depending on the environmental conditions. 相似文献108.
Equine arteritis virus (EAV) induces apoptosis in infected cells. Cell death caused by EAV has been studied mainly using three cell lines, BHK-21, RK-13 and Vero cells. The mechanism of apoptosis varies among cell lines and results cannot be correlated owing to differences in EAV strains used. We evaluated different markers for apoptosis in BHK-21, RK-13 and Vero cell lines using the Bucyrus EAV reference strain. Acridine orange/ethidium bromide staining revealed morphological changes in infected cells, while flow cytometry indicated the extent of apoptosis. We also observed DNA fragmentation, but the DNA ladder was detected at different times post-infection depending on the cell line, i.e., 48, 72 and 96 h post-infection in RK-13, Vero and BHK-21 cells, respectively. Measurement of viral titers obtained with each cell line indicated that apoptosis causes interference with viral replication and therefore decreased viral titers. As an unequivocal marker of apoptosis, we measured the expression of caspase-3 and caspases-8 and -9 as extrinsic and intrinsic markers of apoptosis pathways, respectively. Caspase-8 in BHK-21 cells was the only protease that was not detected at any of the times assayed. We found that Bucyrus EAV strain exhibited a distinctive apoptosis pathway depending on the cell line. 相似文献
109.
Mervat M. A. El-Gendy Ahmed M. A. EL-Bondkly 《Journal of industrial microbiology & biotechnology》2010,37(8):831-841
As a part of our ongoing efforts towards finding novel antimycotic agents from marine microflora of the Red Sea, vanillin,
5,7-dimethoxy-4-p-methoxylphenylcoumarin and the new antimycotic compound saadamycin were isolated from endophytic Streptomyces sp. Hedaya48. The producing strain was isolated from the Egyptian sponge Aplysina fistularis and subjected to different UV irradiation doses. A mutant strain Ah22 with 10.5-fold (420 mg/l as compared to 40 mg/l produced
by the parental strain) improved saadamycin production was isolated. Production of saadamycin from mutant Ah22 was enhanced
to 2.26-fold (950 mg/l) and 2.38-fold (1000 mg/l) under optimized culture conditions in batch culture and bioreactors, respectively.
Both saadamycin and 5,7-dimethoxy-4-p-methoxylphenylcoumarin exhibited significant antimycotic activity against dermatophytes and other clinical fungi. 相似文献
110.
Higher-primate phylogeny--why can't we decide? 总被引:2,自引:0,他引:2
At present, no definitive agreement on either the correct branching order
or differential rates of evolution among the higher primates exists,
despite the accumulated integration of decades of morphological,
immunological, protein and nucleic acid sequence data, and numerous
reasonable theoretical models for the analysis, interpretation, and
understanding of those data. Of the three distinct unrooted phylogenetic
trees, that joining human with chimpanzee and the gorilla with the
orangutan is currently favored, but the two alternatives that group humans
with either gorillas or the orangutan rather than with chimpanzees also
have support. This paper is a synthetic and critical review of the
methodological literature and isolates some 20 specific reasons why
uncertainty in the evolutionary understanding of our closest living
relatives persists. Many of the difficulties are eliminated or ameliorated
by Lake's new methods of phylogenetic invariants and operator metrics. In
the companion paper these new methods are used to analyze both the nuclear
and mitochondrial DNA of the higher primates.
相似文献