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11.
《Reproductive biology》2022,22(1):100600
Circular RNAs (circRNAs) have been identified as critical regulators in human cancers, including cervical cancer (CC). However, the precise action of circ_0084904 in cervical carcinogenesis remains to be elucidated. The levels of circ_0084904, microRNA (miR)-802, and Mal, T cell differentiation protein 2 (MAL2) were checked by quantitative real-time PCR (qRT-PCR) or western blot. Ribonuclease R (RNase R) and subcellular localization assays were used to detect the stability and localization of circ_0084904, respectively. Cell colony formation ability was assessed by colony formation assay. Cell cycle and apoptosis were detected by flow cytometry. Cell migration and invasion abilities were gauged by transwell assay. Dual-luciferase reporter and RNA immunoprecipitation (RIP) assays were applied to determine the direct relationship between miR-802 and circ_0084904 or MAL2. The xenograft experiments were performed to evaluate the role of circ_0084904 in tumor growth in vivo. Circ_0084904 was markedly up-regulated in CC tissues and cell lines. Silencing endogenous circ_0084904 impeded cell colony formation, cell cycle progression, migration, invasion, epithelial-mesenchymal transition (EMT), and promoted apoptosis in vitro, as well as diminished tumor growth in vivo. Mechanistically, circ_0084904 targeted miR-802, and the effects of circ_0084904 silencing were mediated by miR-802. MAL2 was directly targeted and inhibited by miR-802, and MAL2 was a functional target of miR-802. Moreover, circ_0084904 modulated MAL2 expression via miR-802. Our study identified circ_0084904 as a novel oncogenic driver in CC depending on the modulation of the miR-802/MAL2 axis, establishing the notion that silencing of circ_0084904 might represent a promising targeted therapy for CC.  相似文献   
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Rheumatoid arthritis (RA) is a chronic inflammatory disorder that can, in severe cases, lead to disability. CC chemokine receptor (CCR), an integral membrane protein, has been suggested to play a key role in the RA developmentThis study is to explore the role of CCR5 silencing in inflammatory response, viability, and apoptosis of synovial cells in RA rats by inactivating the mitogen-activated protein kinase (MAPK) signaling pathway. Microarray analysis was conducted to screen out differentially expressed genes from RA-related chips. The rat model was established by injection of siRNA-CCR5 and PD98059 (inhibitor of mitogen-activated protein kinase kinase 1) to evaluate the role of CCR5 silencing in RA, with the involvement of inflammatory response, synovial cell viability, apoptosis, and cycle. CCR5 was predicted to participate in RA by regulating the MARK pathway. In animal experiments, reduction was identified in arthritis index (AI), CCR5 positive expression rate, levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), matrix metalloproteinase (MMP)-1, and MMP-3 in serum of RA rats after CCR5 siRNA and PD98059 injections. RA rats treated with CCR5 siRNA, and PD98059 presented with inhibition in cell viability, promotion of apoptosis, increase in cell proportion in G0/G1 phase, and shortened the S phase. In addition, the treatment of CCR5 siRNA, and PD98059 resulted in downregulated JNK1, ERK1, p38, Cyclin D1, Cyclin E1, Cyclin B1, and Bcl-2 and upregulated Bax and Cas3. These findings reveal that CCR5 silencing suppresses inflammatory response, inhibits viability, and promotes apoptosis of synovial cells in RA rats by inhibiting MAPK pathway. Therefore, CCR5 silencing may provide a novel therapeutic target for RA.  相似文献   
15.

Objective

The purpose of this study is to provide a further theoretical basis for the role of Suberoyllanilide hyroxamic acid (SAHA) affect on Dendritic cells (DCs).

Methods

We first downloaded the GSE74306 microarray data, which was about the effect of SAHA act on DCs, from the Gene Expression Omnibus database. Then we analyzed the differential expression genes (DEGs) between SAHA-treated DCs and SAHA-untreated DCs by limma package of R software; The Database for Annotation, Visualization and Integrated Discovery was used to analyze the Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways for these DEGs. The protein protein interaction (PPI) network was constructed by using STRING database, Cytoscape 3.6.1 software was used to dispose the PPI network for visualization. Finally, we determine the Hub genes in the PPI network according by the degree centrality and betweenness centrality, which were calculated by the CentScaPe 2.2 plug-in of Cytoscape 3.6.1 software.

Result

There were 551 DEGs between SAHA-treated DC cells and SAHA-untreated DC cells, including 357 upregulated genes and 194 downregulated genes. These DEGs genes were enriched in 115 Go terms (Biological Process, 51; Cellular Component, 35 and Molecular Function, 29) and a total of 16 pathways. Glutathione metabolic process, Glutathione metabolism pathway, Rheumatoid arthritis pathway and Systemic lupus erythematosus pathway were most significant function clusters. In the PPI network, Rad51, Src, and Eno2 were Hub genes.

Conclusion

The biological function and KEGG pathway enriched by DEGs may reveal the molecular mechanism of SAHA acting on DC cells. Its Hub genes, Src, Rad51 and Eno2, were expected to be new targets for SAHA therapeutic effects. However, it still need to be confirmed by the next more rigorous molecular biological experiments research.  相似文献   
16.
Levels of p,p-DDT and its metabolites in surficial sediments of Tagus and Sado Estuary and lagoon Ria Formosa varied one or two orders of magnitude. In general, p,-DDE and p,-DDD were the dominant metabolites and p,-DDT was a minor component. While concentrations of p,-DDT, p,-DDD and p,-DDE were hardly related to loss on ignition, concentrations of total DDT (tDDT) in surficial sediments of each studied system were positively correlated to that parameter. Higher contaminated samples were excluded from these relationships: a few sediment samples from the Tagus outlet channel, most of the sediments from the upper Sado Estuary, and some particulate matter samples collected in sediment traps in the adjoining area to the Ria Formosa. Concentration of tDDT appears, thus, to be related to sedimentary organic matter of these estuarine systems except near the actual sources of pollution. On the basis of the relationship slopes, one may conclude that lower Tagus Estuary is more contaminated than Ria Formosa and lower Sado Estuary.  相似文献   
17.
The Clara cell is believed to be the progenitor of the peripheral airway epithelium, and it produces the surfactant proteins SP-A and SP-B, in addition to the 10-kDa Clara cell secretory protein (CCSP or CC10). To date, attempts to develop Clara cell lines have been unsuccessful. Most such attempts have involved the in vitro insertion of a transforming viral oncogene. We have reported previously the characterization of a differentiated conditionally immortalized murine lung Type II epithelial cell line, T7, from the H-2Kb-tsA58 transgenic mouse. We have also used this mouse model to derive Clara cell lines. In this model, the need for in vitro gene insertion is circumvented by the creation of a transgene, in which the large tumor antigen of a temperature-sensitive strain (tsA58) of the simian virus 40 (SV40) is fused with the major histocompatibility complex promoter H-2Kb. The promoter is active in a wide range of tissues and is induced by interferons (IFN). From the lungs of animals harboring the hybrid construct, we isolated and characterized Clara cells. The cells contain dense secretory granules and mitochondria typical of Clara cells, and express SP-A, SP-B, SP-D, and the Clara cell secretory protein, CC10. Withdrawal of the IFN and elevation of the incubation temperature permit normal cell differentiation similar to that of Clara cells in vivo. This cell line should be very useful for the investigation of normal Clara cell function and gene expression.  相似文献   
18.
Most preservative-treated wood produced and consumed in the United States is treated with toxic inorganic compounds containing copper, chromium, and arsenic. Because chromated copper arsenate (CCA) is fixed to the wood, CCA-treated wood has not been considered toxic or hazardous and it is currently disposed of in approved landfills. Growing public concern about environmental contamination from treated wood combined with the removal of greater quantities of CCA-treated wood from service have presented a disposal challenge for this fiber source. In this study, CCA-treated wood was processed by acid extraction, steam explosion, and bacterial fermentation and evaluated for removal of copper, chromium, and arsenic. Copper was the easiest to remove by these treatments and chromium the most resistant to removal. Exposing CCA-treated wood to steady-state bacterial growth by continuous culture with Bacillus licheniformis CC01 did not enhance removal of CCA components compared to standard mixed culture when acid extraction preceded bacterial fermentation. Nor did steam explosion, alone or in conjunction with acid extraction and bacterial fermentation, enhance removal of CCA components; the chromium and arsenic components resisted removal. Grinding CCA-treated wood chips into 20-mesh sawdust provided greater access to and removal of CCA components by all processes. However, grinding the chips was unnecessary if they were treated with acid prior to bacterial fermentation. Extraction with oxalic acid as a precursor to bacterial fermentation with B. licheniformis CC01 removed 90% copper (CuO), 80% chromium (CrO3), and 100% arsenic (As2O5) from treated chips. The combination of acid extraction and bacterial fermentation removed 80–100% of these metals from CCA-treated wood. Received 15 December 1997/ Accepted in revised form 08 March 1998  相似文献   
19.
Some tricyclic tetrahydroquinolines (THQs) were found to have the potential of a new series of nonsteroidal selective androgen receptor modulators (SARMs). Compound 5b was first designed and synthesized under our hypothesis based on a four-point pharmacophoric requirement of the 3-carbonyl, 18-methyl, 17-hydroxyl, and 13-quaternary carbon groups of dihydrotestosterone (DHT). It was revealed that this compound exhibits not only a strong androgen receptor (AR) agonistic activity (EC50 = 9.2 nM) but also the highest selectivity in binding affinity to AR among the steroid hormone receptors. Furthermore, this compound showed a weak virilizing effect with retention of the desired anabolic effect as compared with DHT in vivo.  相似文献   
20.
C(H)2-domain-deleted CC49 (HuCC49DeltaCH2), a recombinant humanized antibody that recognizes the TAG-72 antigen expressed on a variety of human carcinomas, is secreted from cultured cells as a mixture of two homodimeric isoforms. Isoform A contains two covalent interchain disulfide bonds at heavy chain positions 239 and 242, while isoform B fails to develop any interchain disulfide bonds but has 239-242 intrachain disulfide bonds instead. Form A is currently in preclinical development as a therapeutic agent for treating colorectal carcinoma, though form B shows equal efficacy. HuCC49DeltaCH2 form B can be crystallized from sodium formate only in the presence of detergents. X-ray diffraction data were collected on a single cryo-cooled crystal grown with Triton X-100 and the structure was solved by molecular replacement. The model has refined to R=0.246 (R(free)=0.297) for 2.8A data. The antibodies pack in the crystal around crystallographic 2-fold axes as tetramers with approximate 222 symmetry. Atomic force microscopy studies show that this tetrameric structure is the crystal building block and also exists free in the mother liquor. The tetramer is composed of two rings, back-to-back, with a thickness of approximately 83A. Each ring is composed of two antibodies with the complementarity-determining regions (CDR) of the two Fabs of one antibody interacting with the CDR regions of the second antibody in a head-to-head fashion. These rings are approximately 167A long and 112A wide. The C(H)3 domain is inverted with respect to the Fabs when compared to the usual orientation found in conventional antibodies. The polypeptides joining the C(H)3 domains to the Fab portions of the antibody are not seen and are almost certainly disordered. The antigen combining site of HuCC49DeltaCH2 is very similar, but not identical, in topology and charge distribution to that of antibody B72.3, which binds a similar epitope on TAG-72. The combining site consists of a deep cleft, heavily lined with aromatic amino acid side-chains but bounded by numerous charged groups.  相似文献   
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