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991.
Nostoc flagelliforme, which is distributed on arid and semi-arid steppes of northwestern parts of China, has attracted increasing interest for
its stress tolerance. In order to gain more insight into the genetic background of N. flagelliforme, we sequenced its partial genomic DNA for similarity analyses against current public databases, followed by phylogenetic
comparison of N. flagelliforme and the potentially related species deduced from the similarity analyses. Approximately 430 kb genomic sequence (~5% of genome
as a rough estimate) was determined from 106 distinct genomic clones. Nucleotide BLAST showed that ~23.1% of the partial genomic
sequence was similar to N. punctiforme genomic DNA and ~12.4% to its plasmid DNA. Similar protein search by online FASTA-protein program showed 46.2% of the similar
proteins had their corresponding orthologs in N. punctiforme genome. Furthermore, phylogenetic comparison based on 16S rRNA sequences showed N. flagelliforme and N. punctiforme clustered closer among the deduced related species. These results indicated that N. punctiforme might also be potentially close neighbor species of N. flagelliforme, in addition to the formerly regarded close neighbor species N. commune and N. sphaeroids. In general, these data enriched our recognition of the evolutionary relationship between N. flagelliforme and other Nostoc species, especially N. punctiforme. 相似文献
992.
993.
Jinping Wu Zhenbiao Jiao Jie Zhou Fengling Guo Zili Ding Zhengming Qiu 《World journal of microbiology & biotechnology》2017,33(7):134
The bacterial community and diversity in healthy and diseased konjac rhizosphere soils with different ages of continuous cropping were investigated using next-generation sequencing. The results demonstrated that the number of years of continuous cropping significantly altered soil bacterial community and diversity. Soil bacterial Shannon diversity index and Chao 1 index decreased with the increasing cropping years of konjac. After 1 year of cropping, the soil exhibited the highest bacterial relative abundance and diversity. Of the 44 bacterial genera (relative abundance ratio of genera greater than 0.3%), 14 were significantly affected by the duration of continuous cropping and plant status. With increasing continuous cropping, Alicyclobacillus decreased, while Achromobacter, Lactobacillus, Kaistobacter, Rhodoplanes increased after 3 years continuous cropping. Continuous cropping altered the structure and composition of the soil bacterial community, which led to the reduction in the beneficial bacteria and multiplication of harmful bacteria. These results will improve our understanding of soil microbial community regulation and soil health maintenance in konjac farm systems. 相似文献
994.
Jatin Machhi Navnit Prajapati Ashutosh Tripathi Zalak S. Parikh Ashish M. Kanhed Kirti Patel Prakash P. Pillai Rajani Giridhar Mange Ram Yadav 《Molecular neurobiology》2017,54(9):6697-6722
Excitotoxicty, a key pathogenic event is characteristic of the onset and development of neurodegeneration. The glutamatergic neurotransmission mediated through different glutamate receptor subtypes plays a pivotal role in the onset of excitotoxicity. The role of NMDA receptor (NMDAR), a glutamate receptor subtype, has been well established in the excitotoxicity pathogenesis. NMDAR overactivation triggers excessive calcium influx resulting in excitotoxic neuronal cell death. In the present study, a series of benzazepine derivatives, with the core structure of 3-methyltetrahydro-3H-benzazepin-2-one, were synthesised in our laboratory and their NMDAR antagonist activity was determined against NMDA-induced excitotoxicity using SH-SY5Y cells. In order to assess the multi-target-directed potential of the synthesised compounds, Aβ1–42 aggregation inhibitory activity of the most potent benzazepines was evaluated using thioflavin T (ThT) and Congo red (CR) binding assays as Aβ also imparts toxicity, at least in part, through NMDAR overactivation. Furthermore, neuroprotective, free radical scavenging, anti-oxidant and anti-apoptotic activities of the two potential test compounds (7 and 14) were evaluated using primary rat hippocampal neuronal culture against Aβ1–42-induced toxicity. Finally, in vivo neuroprotective potential of 7 and 14 was assessed using intracerebroventricular (ICV) rat model of Aβ1–42-induced toxicity. All of the synthesised benzazepines have shown significant neuroprotection against NMDA-induced excitotoxicity. The most potent compound (14) showed relatively higher affinity for the glycine binding site as compared with the glutamate binding site of NMDAR in the molecular docking studies. 7 and 14 have been shown experimentally to abrogate Aβ1–42 aggregation efficiently. Additionally, 7 and 14 showed significant neuroprotective, free radical scavenging, anti-oxidant and anti-apoptotic properties in different in vitro and in vivo experimental models. Finally, 7 and 14 attenuated Aβ1–42-induced tau phosphorylation by abrogating activation of tau kinases, i.e. MAPK and GSK-3β. Thus, the results revealed multi-target-directed potential of some of the synthesised novel benzazepines against excitotoxicity. 相似文献
995.
Advances in synthetic biology are contributing to diverse research areas, from basic biology to biomanufacturing and disease
therapy. We discuss the theoretical foundation, applications, and potential of this emerging field. 相似文献
996.
Nabil M. Abdel-Hamid 《The Journal of membrane biology》2009,230(3):155-162
Chemical composition of extracellular matrix (ECM) plays a pivotal role in cellular and tissue development, regeneration,
and differentiation. It also plays a key role in pathogenesis of hepatocellular carcinoma (HCC). This study explored premalignant
changes in the liver tissue content of collagen (as hydroxyproline, HP), total glycosaminoglycans (TGAGs), free glucosamine
(FGA), total sialic acid (TSA), lysosomal membrane integrity variations (calculated as total and free cathepsin D activities),
and liver histology. Serum alfa-fetoprotein (AFP) level was used as an early marker for HCC in two groups of Wistar rats.
One group of rats served as control and was provided normal saline orally. The other group was provided trichloroacetic acid
(TCA) as 0.5 g/kg/day for five consecutive days by oral gavage. Animals were killed before tumor development. The treatment
revealed dysplastic changes in addition to microsteatosis (fatty changes). Both sinusoids and the portal vein among dysplastic
cells were dilated and congested. These dysplastic foci are believed to be premalignant and may be precancerous lesions. The
following things were observed: a highly significant increase in serum AFP (as a key marker for HCC), a significant decrease
in HP and TSA, a significant increase in FGA, nonsignificant decrease in TGAGs, significant up-regulation of free cathepsin
D, nonsignificant decrease in total cathepsin D activities, and destabilization of lysosomal membrane integrity. Down-regulation
of HP, TSA, and TGAGs seems to be a prerequisite for cancer development. This might be stimulated by up-regulation of free
cathepsin D activity. Perhaps tissue fibrosis is not a condition for developing HCC because collagen was significantly depressed.
Up-regulated FGA could be assumed to be a defense mechanism against TCA-induced proteolysis of membrane proteins because it
is frequently reported to be of value in cancer chemotherapy. Studied ECM perturbations can be assumed as preliminary changes
during chemical hepatocarcinogenesis at the tissue level. Prospective studies on blood levels of cathepsins, TGAGs, and individual
ECM variables such as TSA, FGA, and Hp in patients at risk for HCC, performed in parallel with assessments of AFP, may provide
a cost-effective way to find new links between tissue changes and circulation that would permit early prediction of disease.
It may also provide a way to monitor HCC and compensate for the missed peak AFP values. 相似文献
997.
Background
In the past decades the rapid growth of molecular diagnostics (based on either traditional PCR or isothermal amplification technologies) meet the demand for fast and accurate testing. Although isothermal amplification technologies have the advantages of low cost requirements for instruments, the further improvement on sensitivity, speed and robustness is a prerequisite for the applications in rapid pathogen detection, especially at point-of-care diagnostics. Here, we describe and explore several strategies to improve one of the isothermal technologies, helicase-dependent amplification (HDA). 相似文献998.
Biological role of MicroRNA-103 based on expression profile and target genes analysis in pigs 总被引:1,自引:0,他引:1
MicroRNAs (miRNAs) are endogenously expressed RNAs consisting of 20–24 nucleotides. These molecules are thought to repress
protein translation by binding to target mRNAs. However, biological functions have not been assigned to most of the 175 porcine
miRNAs registered in miRBase (release 15.0). In an effort to uncover miR-103 important in pigs, we examined the integrative
tissue expression profile and gene ontology (GO) term enrichment of predicted target genes to determine the global biological
functions of miR-103. Our results demonstrated that miR-103 is involved in various biological processes including brain development,
lipid metabolism, adipocyte differentiation, hematopoiesis, and immunity. Moreover, we also experimentally verified effects
of miR-103 in porcine preadipocytes. miR-103 levels increased in differentiating adipocytes, and inhibition of miR-103 effectively
inhibited preadipocyte differentiation. In addition, mRNA levels of the putative miR-103 target RAI14 were higher in miR-103 inhibitor-treated adipocytes. These results demonstrate that miR-103 is involved in porcine preadipocyte
differentiation and may act through the putative target gene RAI14. In a word, our data provide new insights into the global biological role of miR-103. 相似文献
999.
Cell fusions are important to fertilization, placentation, development of skeletal muscle and bone, calcium homeostasis and
the immune defense system. Additionally, cell fusions participate in tissue repair and may be important to cancer development
and progression. A large number of factors appear to regulate cell fusions, including receptors and ligands, membrane domain
organizing proteins, proteases, signaling molecules and fusogenic proteins forming alpha-helical bundles that bring membranes
close together. The syncytin family of proteins represent true fusogens and the founding member, syncytin-1, has been documented
to be involved in fusions between placental trophoblasts, between cancer cells and between cancer cells and host cells. We
review the literature with emphasis on the syncytin family and propose that syncytins may represent universal fusogens in
primates and rodents, which work together with a number of other proteins to regulate the cell fusion machinery. 相似文献
1000.
Allister EM Pal S Thomson AM Helmerhorst E Mamo JC 《Journal of biomedical science》2004,11(6):789-798
We compared the acute effect of insulin on the human colonic intestinal epithelial cell line CaCo-2 and the transformed human hepatic cell line HepG2. Over 24 h, 100 nM and 10 µM insulin significantly inhibited the secretion of apolipoprotein (apo) B-100 from HepG2 cells to 63 and 49% of control, respectively. Insulin had no effect on the secretion of apoB-48 from CaCo-2 cells. There was no effect of insulin on the cholesterol ester or free cholesterol concentrations in HepG2 or CaCo-2 cells. HepG2 and CaCo-2 cells bound insulin with high affinity, leading to similar stimulation of insulin receptor protein tyrosine kinase activation. Protein kinase C or mitogen-activated protein kinase activity in the presence or absence of insulin was not correlated with apoB-48 production in CaCo-2 cells. Therefore, insulin acutely decreases the secretion of apoB-100 in hepatic HepG2 cells, but does not acutely modulate the production or secretion of apoB-48 from CaCo-2 intestinal cells. 相似文献