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Three hundred and twenty endophytic actinobacterial strains were isolated from psammophytes collected from Taklamakan Desert and identified.Among them,three strains already had been identified as new species of two genera and sixteen isolates showed relatively low 16S rRNA similarities＜98.6％to validly described species.Seventy-five of the isolates were selected as representative strains to screen antibacterial activity and mechanism.Forty-seven strains showed antagonistic activity against at least one of the indicator bacteria.Two Streptomyces strains produced bioactive compounds inducing DNA damage,and two Streptomyces strains produced bioactive compounds with inhibitory activity on protein biosynthesis.Notably,the strain Streptomyces sp.8P21H-1 that demonstrated both strong antibacterial activity and inhibitory activity on protein biosynthesis was prioritized for exploring new antibiotics.Under the strategy of integrating genetics-based discovery program and MS/MS-based molecular networking,two new streptogramin-type antibiotics,i.e.,acetyl-griseoviridin and desulphurizing gri-seoviridin,along with known griseoviridin,were isolated from the culture broth of strain 8P21H-1.Their chemical structures were determined by HR-MS,and 1D and 2D NMR.Desulphurizing griseoviridin and griseoviridin exhibited antibacterial activities by inhibiting translation.
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Objective To investigate associations of herpes simplex virus(HSV)infection with elevated high-sensitivity C-reactive protein(hsCRP)level and the development of atrial fibrillation(AF) in elderly individuals.Methods Through screening a total of 2,603 individuals,49 patients aged 60 years or over with AF and without structural heart diseases and known risk factors for AF were selected for data collection.Fifty-five elderly healthy control subjects were selected from a population based Chinese Arrhythmia Registry.Baseline characteristics,plasma antibody levels against HSV-1 and-2,and level of hsCRP were analyzed.Results Level of antibodies against HSV-1 was significantly higher in AF patients[(314.5±63.6)mg/L than in control subjects(216.0±50.7) mg/L,P＜0.01].Level of antibodies against HSV-2 was significantly higher in AF patients[(400.1±50.7) mg/L than in control subjects (306.3 ± 64.5) mg/L,P ＜ 0.01].Linear regression analysis demonstrated a positive correlation of plasma levels of hsCRP with both anti-HSV-1 and anti-HSV-2 IgG antibodies (r =0.291,0.188,all P ＜ 0.01).In multiple logistic regression analysis,HSV-1 and HSV-2 antibody levels were significantly associated with AF occurrence(OR =1.035 and 1.034,all P ＜0.01).The optimal cut-off point for predicting AF occurrence was 284.96 mg/L for anti-HSV-1 with sensitivity of 67.3％ and a specificity of 92.7％,and was 366.26 mg/L for anti-HSV-2 with a sensitivity of 67.3％ and a specificity of 85.5％,respectively.Conclusions The increased plasma levels of anti-HSV-1 and anti-HSV-2 antibodies are significantly associated with AF occurrence in elderly adults.
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Objective: To purify the recombinant protein by using the constructed pET28a-APTP-oc recombinant expression plasmid, and to prepare the rabbit polyclonal antibody against osteoclastic protein tyrosine phosphatase (PTP-oc) and to identify its properties. Methods: The constructed pET28a-APTP-oc recombinant plasmid vyas transformed into E.CO BL21 (DE3), and the isopropyl-ß-D-thiogalactoside (IPTG) vyas used to induce the expression of recombinant protein. The recombinant protein vyas purified by the method of Q fast flovy agarose and Ni-NTA agarose, and the purified recombinant protein vyas used as an antigen to immunize the rabbit to obtain PTP-oc polyclonal antibody. The titer and specificity of the antibody vyere identified by indirect ELISA and Western blotting methods. Results: The recombinant PTP-oc protein vyas successfully purified. The indirect ELISA results shovyed that after immunizing the rabbit vyith the recombinant PTP-oc protein, the polyclonal antibody vyith the titer of 1 : 3 2000 vyas gotten. The Western blotting results shovyed that the polyclonal antibody had high specificity. Conclusion: The PTP-oc recombinant protein is successfully purified, and the polyclonal antibody of PTP-oc is prepared successfully.
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Objective:To investigate the effects of ursolic acid (UA) on the proliferation and differentiation of osteoclasts (OC), and to explore its role in orthodontic force-induced root resorption and its relationship with OC.Methods:The mononuclear / macrophage cells RAW264.7 were induced to the OC.Tacrolimus acid phosphatase (TRAP) staining and bone resorption lacunae observation were used to identify the induction.CCK-8 method was used to select the appropriate concentration of UA for RAW264.7 cell-free biotoxicity and to observe its effect on the proliferation and differentiation of RAW264.7.In experimental groups, UA with gradient concentrations (1.0,2.5,5.0,10.0,20.0and 40.0 μmol·L-1)were added.UA was not added in control group.Results:The TRAP staining and bone resorption lacunae observation showed that after the RAW264.7 cells were induced for 5 d, the TRAP staining positive cells were found;the resorption lacunae were rounded,and oval, etc,the bottom wall was coarser,and the boundary was clear,which indicated that the RAW264.7 cells were successfully differentiated into the osteoclasts.The CCK-8 detection results showed that high concentration of UA (> 10.0 μmol·L-1) significantly inhibited the proliferation of OC;the appropriate concentration of UA (5.0 μmol·L-1) was in the biological safety concentration range and could inhibit the OC proliferation;low concentration of UA (<2.5 μmol·L-1) had no effect.Conclusion:RANKL can induce the differentiation and maturation of RAW264.7 cells.UA is correlated with the proliferation and differentiation of OC;UA has inhibitory effect on OC at the appropriate concentration (5.0 μmol·L-1) in a time-dependent manner.
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Objective To investigate the relationship of vitamin D with the intestinal development and study the expression of vitamin D receptor (VDR) in the duodenum of C57BL/6 mice at different developmental stages.Methods Quantitative PCR (qPCR),histology using H&E staining and immunofluorescence staining,and Western blotting (WB) were performed to elucidate the expression of VDR in mice intestine at different growth and developmental stages.Results The peak of VDR mRNA expression reached on 21 d.The pathological result showed that VDR mainly distributed in the cytoplasm of epithelial cells and smooth muscle cells in the mouse duodenum.WB result indicated that there was no nuclear translocation of VDR protein in the mouse duodenum.Conclusions This study demonstrates the regularity of expression of VDR in the mouse duodenum during its development,and contributes to understanding the function of VDR in the intestines.
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Objective:To study the changes of oral health indexes in adolescent orthodontic patients under different brushing time, and to provide basis for the orthodontists to give effective dental health promotion in clinic.Methods:A total of 123 adolescent orthodontic patients were included, and they were divided into 1-3min, 3-5 min, 5-7 min and 7-10 min groups based on the brushing time recorded in the period of orthodontic treatment.The relationship between different brushing time and oral health indexes was evaluated 1,3,and 6 months after experiment, such as sulcus bleeding index(SBI),plaque index(PLI), debris index-simplified(DI-S) and enamel demineralization index(EDI).Results:Compared with 1-3 min and 3-5 min groups, the SBI, PLI, and DI-S of the patients in 5-7 min group were significantly reduced(P0.05).Conclusion:Brushing teeth more than 5 min can improve the oral hygiene significantly and the best time is 5-7 min;the orthodontists should require the patients to brush teeth at least for 5 min.
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Aim To observe the effect of mineralocor-ticoid receptor blockade eplerenone on cell proliferation in obstructed kidney of rats. Methods Renal intersti-tial fibrotic animals were made with unilateral ureteral obstruction (UUO) and treated with eplerenone100 mg · kg - 1 · d - 1 . The kidneys were harvested on the 10th day and proliferating cell nuclear antigen ( PC-NA ), serum and glucocorticoid induced kinase-1 (SGK-1 ) and transforming growth factor-β1 ( TGF-β1 ) were detected with immunohistochemistry and Western blot. Results Renal histopathology showed large quantities extracellular matrix (ECM) accumula-tion in kidney with UUO, large numbers of inflammato-ry cells infiltrated in renal interstitium, renal tubular expansion and exfoliation of epithelial cells . The cell proliferation and ECM accumulation were inhibited in eplerenone treated rats significantly. Immunohisto-chemistry and Western blot showed that expressions of PCNA,SGK-1 and TGF-β1 were significantly up-regu-lated with UUO and down-regulated by eplerenone. Conclusion Eplerenone plays the role in inhibiting the cell proliferation and reducing ECM accumulation by down-regulating expression of SGK-1 pathway in rats with unilateral ureteral obstruction.