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1.
Artigo em Inglês | MEDLINE | ID: mdl-31912865

RESUMO

Accumulating evidence has indicated that microRNAs can regulate downstream signaling pathways and play an important role in various tumors. In this study, we found that miR-223-3p was differentially expressed in 40 paired gastric cancer tissues and adjacent tissues and that miR-223-3p was positively correlated with tumor invasion depth and lymph node metastasis. Luciferase reporter assay confirmed that Arid1a was the target gene of miR-223-3p. Functional assays showed that miR-223-3p promoted the proliferation and invasion of gastric cancer cells by regulating the expression of Arid1a. We also confirmed that miR-223-3p regulated the growth of gastric cancer cells in vivo, while an antagomir against miR-223-3p significantly inhibited tumor growth. In conclusion, our results demonstrated that miR-223-3p inhibits gastric cancer cell progression by decreasing the expression of Arid1a. Therefore, miR-223-3p may act as a potential therapeutic target for patients with gastric cancer.

2.
Nano Lett ; 20(1): 418-425, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31816244

RESUMO

Batteries using lithium (Li) metal as the anode are considered promising energy storage systems because of their high specific energy densities. The crucial bottlenecks for Li metal anode are Li dendrites growth and side reactions with electrolyte inducing safety concern, low Coulombic efficiency (CE), and short cycle life. Vinylene carbonate (VC), as an effective electrolyte additive in Li-ion batteries, has been noticed to significantly enhance the CE, whereas the origin of such an additive remains unclear. Here we use cryogenic transmission electron microscopy imaging combing with energy dispersive X-ray spectroscopy elemental and electron energy loss spectroscopy electronic structure analyses to reveal the role of the VC additive. We discovered that the electrochemically deposited Li metal (EDLi) in the VC-containing electrolyte is slightly oxidized with the solid electrolyte interphase (SEI) being a nanoscale mosaic-like structure comprised of organic species, Li2O and Li2CO3, whereas the EDLi formed in the VC-free electrolyte is featured by a combination of fully oxidized Li with Li2O SEI layer and pure Li metal with multilayer nanostructured SEI. These results highlight the possible tuning of crucial structural and chemical features of EDLi and SEI through additives and consequently direct correlation with electrochemical performance, providing valuable guidelines to rational selection, design, and synthesis of additives for new battery chemistries.

3.
Neurobiol Learn Mem ; 167: 107136, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31812581

RESUMO

Clinical and preclinical researches have shown that sub-anesthetic ketamine elicits sustained antidepressant effects for up to 1-2 weeks. Pharmacokinetics studies (t1/2 = 23 min) in mice showed no ketamine residue at 24 h after sub-anesthetic or anesthetic ketamine administration. Therefore, this study aims to reveal the mechanism underlying these different biological functions at 24 h after sub-anesthetic and anesthetic ketamine treatment. First, at the animal behavioral level, we found that sub-anesthetic ketamine induced antidepressant and anxiolytic effects while anesthetic ketamine induced depressive-like phenotypes and cognitive impairment. Second, we examined the correlation between behavior phenotype and protein expression, and found that the Brain-derived neurotrophic factor (BDNF) level is oppositely regulated by sub-anesthetic and anesthetic ketamine. Sub-anesthetic ketamine significantly increased the BDNF level, correlating to antidepressant effects; whereas anesthetic dose reduced BDNF expression in the hippocampus, correlating to depressive-like behaviors, anxiety-like behaviors and cognitive impairment. Third, the antidepressant effects of sub-anesthetic ketamine were prevented by pre-treatment of ANA-12, a Tropomyosin receptor kinase B (TrkB) inhibitor. Thus, we conclude that BDNF may be the key factor underlying antidepressant and anxiolytic effects of sub-anesthetic ketamine at 24 h after treatment. These results may shed light on future studies and the development of long-lasting anti-depressant drugs and therapies.

4.
Sci Total Environ ; 698: 134141, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31505366

RESUMO

The rhizomes of Coptis chinensis Franch., Coptis deltoidea C. Y. Cheng et Hsiao and Coptis teeta Wall, are sources of renowned traditional Chinese medicines. Recently, human activities and climate change has caused degeneration of the natural habitats of these pharmacological plants. Analyzing the impact of climate change on the possible distribution of Coptis herbs is essential for their future conservation and domestication. The purpose of this study was to predict the potential distribution of these valuable plants and identify the potential effects of climate change on three Coptis species, using of species distribution modeling (SDM). In this study, we first predict the distribution size variations of the three plant species, under present and future conditions. Secondly, we carried out field sampling of these three species and analyzed the chemical composition by high performance liquid chromatography (HPLC). Results show that the predicted distributions of all three Coptis herbs were not limit to the reported regions, but also cover other potential areas. Among the environmental variables, annual precipitation range (Bio2) induced the largest impact on SDMs for C. chinensis (72.2%) and C. deltoidea (37.9%), while C. teeta was more significantly affected by isothermally (Bio3, 39.2%). When comparing the possible future distribution to the present distribution of these species, a decreasing tendency was observed in the highly suitable areas of C. chinensis and the generally suitable areas of C. teeta, indicating that the environmental changes would affect the distribution of these two species. In addition, the average alkaloid content was found to be the highest in highly suitable areas, while it was decreased in moderately and generally suitable areas, indicating that alkaloid content may be related to environmental factors. In summary, these findings improve our understanding of the ecological impact of climate on the distribution of three Coptis species.


Assuntos
Mudança Climática , Coptis , Monitoramento Ambiental , Modelos Estatísticos , China , Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa
5.
Animals (Basel) ; 9(12)2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31835883

RESUMO

The objective of this study was to evaluate the effects of dietary energy levels on growth performance, rumen fermentation and bacterial community, and meat quality of Holstein-Friesians bulls slaughtered at different ages. Thirty-six Holstein-Friesians bulls (17 months of age) were divided into a 3 × 3 factorial experiment with three energy levels (LE, ME and HE; metabolizable energy is 10.12, 10.90 and 11.68 MJ/kg, respectively) of diets, and three slaughter ages (20, 23 and 26 months). Results indicated that bulls fed with ME and HE diets had higher dry matter intake, average daily gain, and dressing percentage at 23 or 26 months of age. The ME and HE diets also reduced bacterial diversity, altered relative abundances of bacteria and produced lower concentrations of acetate, but higher butyrate and valerate concentrations in rumen fluid. Increasing in dietary energy and slaughter age increased the intramuscular fat (IMF) and water holding capacity. In summary, Holstein-Friesians bulls fed with ME and HE diets, slaughtered at 23 and 26 months of age could be a good choice to produce beef with high IMF. Slaughter age may have less influence than dietary energy in altering fermentation by increasing amylolytic bacteria and decreasing cellulolytic bacteria, and thus, further affecting meat quality.

6.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(6): 1955-1961, 2019 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-31839066

RESUMO

OBJECTIVE: To establish a flow cytometric immunobead array assay (FCIA) to quantify platelet antibodies and to explore its application in the diagnosis and treatment of ITP. METHODS: The guantitative standard curve was established by binding the human IgG of known concentration on antibody-coated microbeads; at the same time, the platelet-specific antigen and antibody complex was captured and levels of platelet antibodies were detected using the microbeads coated by 5 kinds of antibodies against platelets suca as GPIX (SZ1), GPⅠb (SZ2), GpⅢa (SZ21), GPⅡb (SZ22) and p-selection (SZ51). The fluorescence signal detected by flow cytometry were transformed into the conentration of platelet antibodies in samples through the quantitative standard curve, thereby establishing the method for quantititive detection of platelet-specific antibodies in plasm samples (FCIA), moreover the property, efficiency and clinical application of establishod FCIA method were evaluated. RESULTS: The FCIA could detect 5 kinds of antibodies against GPIX, GPⅠb, GpⅢa, GPⅡb and ß-selection within a broad range of 33.29-1280 ng/ml, 45.17-1280 ng/ml, 42.07-1280 ng/ml, 46.40-1280 ng/ml, 42.48-1280 ng/ml and 42.48-1280 ng/ml respectively, and their recovery rates were 115.23%, 112.58%, 117.47%, 107.64% and 112.67% respectively. The intra-assay coefficient of variation (CV) for anti- GPIX, -GPⅠb, -GpⅢa, -GPⅡb and p-selection antibodies was 3.54%, 3.63%, 4.66%, 6.43% and 6.67% respectively, and the inter-assay CV for above mentioned antibodies were 10.89%, 7.57%, 10.34%, 6.95% and 10.72% respectively. The detection showed that the levels of 5 kinds of platelet-specific antibodies in ITP group all were higher than those in non-ITP and healthy control groups (P<0.01). The sensitivity, specificity and accuracy of quantitatively detecting 5 kinds of antibodies for diagnosis of ITP by FCIA were 68.29%, 84.98% and 78.95% respectively, while the sensitivity, specificity and accuracy of detecting 5 kinds of antibodies by modified indirect MAIPA were 41.46%, 90.41% and 72.81% respectively. CONCLUSION: The established quantitative FCIA for detection of antibodies provides a powerful tool for diaghosis and evaluation of therapeutic efficacy and prognosis of ITP patients.


Assuntos
Plaquetas , Púrpura Trombocitopênica Idiopática , Anticorpos , Autoanticorpos , Citometria de Fluxo , Humanos
7.
Rapid Commun Mass Spectrom ; : e8694, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31826305

RESUMO

RATIONALE: Discovering and identifying new small-molecule inhibitors of monoamine oxidase B (MAO-B) have the potential to treat many neurodegenerative diseases. METHODS: We employed affinity ultrafiltration-liquid chromatography-tandem mass spectrometry (AUF-LC/MSn ) to identify and characterize small-molecule inhibitors of MAO-B from the 30% ethanol extract of Acanthopanax senticosus root (ASR). In vitro tests were performed in stimulated BV2 microglia to evaluate the anti-inflammatory effects of the ASR preparation. An in vitro enzyme activity assay, measuring half-maximal inhibitory concentrations (IC50 ) against MAO-B, determined the inhibitory activity of the potential MAO-B ligands. RESULTS: ASR treatment significantly inhibited NO release (p<0.01) and attenuated tumor necrosis factor (TNF)-α expression in stimulated BV2 microglia. Nine compounds were isolated from the ASR preparation as potential MAO-B inhibitors, identified as quinic acid, chlorogenic acid, isofraxidin, dicaffeoylquinic acid, pinoresinol diglucoside, medioresinol 4'-O-ß-D-glucopyranoside, eletutheroside E, syringaresinol O-ß-D-glucoside, and trihydroxy-octadecenoic acid, based on their tandem mass spectra. CONCLUSIONS: Our study provides critical data on compounds from ASR extracts, which are suitable for the development of new MAO-B inhibitors as potential therapeutics for neurodegenerative diseases.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31816140

RESUMO

By using in situ aberration-corrected environmental transmission electron microscopy, for the first time at atomic level, the dynamic evolution of the Cu surface is captured during CO oxidation. Under reaction conditions, the Cu surface is activated, typically involving 2-3 atomic layers with the formation of a reversible metastable phase that only exists during catalytic reactions. The distinctive role of CO and O2 in the surface activation is revealed, which features CO exposure to lead to surface roughening and consequently formation of low-coordinated Cu atoms, while O2 exposure induces a quasi-crystalline CuOx phase. Supported by DFT calculations, it is shown that crystalline CuOx reversibly transforms into the amorphous phase, acting as an active species to facilitate the interaction of gas reactants and catalyzing CO oxidation.

9.
Sci Rep ; 9(1): 19320, 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31848415

RESUMO

The drawbacks of low porosity, inferior electrolyte wettability, low thermal dimensional stability and permissive lithium dendrite growth of the conventional microporous polyolefin-based separators hinder their widely application in the high power density and safe Lithium ion batteries. Herein, highly porous polybenzimidazole-based separator is prepared by a facile non-solvent induced phase separation process (NIPS) using water, ethanol, chloroform and ethyl acetate as the coagulation bath solvent, respectively. It was found that the ethanol is suitable to fabricate uniform morphology macroporous separator with the porosity of 92%, electrolyte uptake of 594 wt.%, and strong mechanical strength of 15.9 MPa. In addition, the experimental tests (electrochemical analysis and XPS test) and density functional theory calculation suggest that the electron-rich imidazole ring of polybenzimidazle can enhance Li+ mobility electrostatic attraction interaction while the block the PF6- mobility via electrostatic repulsion interaction. Therefore, high Li+ transference number of 0.76 was obtained for the neat polybenzimidazole-based polymer electrolyte. As a proof of concept, the Li/LiFePO4 cell with the polybenzimidazole-based polymer electrolyte/1.0 M LiPF6- ethylene carbonate/dimethyl carbonate (v:v = 1:1) electrolyte exhibits excellent rate capability of >100 mAh g-1 at 6 C (1 C = 170 mA g-1) and superior cycle stability of 1000 cycles.

10.
J Neurol Sci ; 410: 116622, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31884351

RESUMO

OBJECTIVE: Percutaneous endoscopic gastrostomy (PEG) and radiologically inserted gastrostomy (RIG) have gained increasing popularity among clinicians and motor neuron disease (MND) patients for maintaining adequate nutritional intake. However, there is no consistent evidence of the efficacy and safety of the two techniques in MND patients. We carried out a systematic review and meta-analysis to examine the technical success rates, complication rates and 30-day mortality of MND patients receiving PEG and RIG. METHODS: We searched PubMed, EMBASE, the Cochrane Library, Web of Science and Scopus from inception to September 12, 2019 for comparative studies on the efficacy and safety of PEG and RIG in MND patients. The primary outcome was technical success rate and the secondary outcomes were complication rates and 30-day mortality. RESULTS: Seven studies (n = 603) were included. Pooled technical success rates were 90.15% in patients receiving PEG and 96.76% in patients undergoing RIG. There was a statistically significant difference in the technical success rate between RIG and PEG, strongly favoring RIG [(OR = 3.96, 95% CI (1.31to 12.02); P = .02]. Pooled major complication rates were 2.19% in patients receiving PEG and 0.07% in patients undergoing RIG, with no statistical difference (P = .08). Pooled procedure-related 30-day mortality rates were 5.31% in patients receiving PEG and 6.00% in patients undergoing RIG, with no statistically significant difference (P = .75). No publication bias was noted. CONCLUSION: The present meta-analysis demonstrated that, compared to PEG, RIG has a higher technical success rate and has a comparable mortality outcome and safety profile.

11.
Huan Jing Ke Xue ; 40(6): 2920-2929, 2019 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854687

RESUMO

Effects of biochar application (at rates of 0%, 1%, and 5%) and field ageing (for 1 a) on the sorption of three antibiotics (sulfadiazine, sulfamethazine, and florfenicol) were studied by batch equilibrium tests for a calcareous purple soil of sloping cropland, which is widely distributed in hilly areas of the upper Yangtze River. A soil-water ratio of 1 g:1 mL, which was close to the actual field soil water content condition, was adopted in the experiment, and comparisons were made to the commonly used ratio of 1 g:10 mL. The results showed that adsorption isotherm data of the studied antibiotics were fitted well by the linear and Freundlich model, and the free energy (ΔGθ) ranged from -0.39 to 11.53 kJ·mol-1, thus indicating that the adsorption of the three antibiotics on the control soils and biochar amended soils was mainly physical adsorption. Application of fresh biochar was found to markedly enhance the adsorption of antibiotics, especially for sulfamethazine and florfenicol of low Kow values, while such an effect was strongly weakened after ageing. The fluorescence peak response intensity of the adsorption equilibrium solution of the aged biochar amended soil was lower than that of the fresh biochar amended soil, so the difference in adsorption performance between fresh and aged biochar amended soils may have been due to the decrease of unstable and soluble organic matter in the latter's biochar after aging.


Assuntos
Antibacterianos/isolamento & purificação , Carvão Vegetal , Poluentes do Solo/isolamento & purificação , Adsorção , Fatores de Tempo
12.
Mol Oncol ; 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31670863

RESUMO

Hepatocellular carcinoma (HCC), with its ineffective therapeutic options and poor prognosis, represents a global threat. In the present study, we show that RAD52 motif 1 (RDM1), a key regulator of DNA double-strand break repair and recombination, is downregulated in HCC tissues and suppresses tumor growth. In clinical HCC samples, low expression of RDM1 correlates with larger tumor size, poor tumor differentiation, and unfavorable survival. In vitro and in vivo data demonstrate that knockdown of RDM1 increases HCC cell proliferation, colony formation, and cell population at G2/M phase, whereas RDM1 overexpression results in the opposite phenotypes. Mechanistically, RDM1 binds to the tumor suppressor p53 and enhances its protein stability. In the presence of p53, RDM1 suppresses the phosphorylation of Raf and ERK. Overexpression of p53 or treatment with ERK inhibitor significantly abolishes cell proliferation induced by the depletion of RDM1. In addition, overexpression of methyltransferase-like 3 markedly induces N6-methyladenosine modification of RDM1 mRNA and represses its expression. Taken together, our study indicates that RDM1 functions as a tumor suppressor and may be a potential prognostic and therapeutic factor for HCC.

13.
Stem Cells Int ; 2019: 2631024, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31772586

RESUMO

Adipose-derived stem cells (ASCs) have become one of the most promising stem cell populations for cell-based therapies in regenerative medicine and for autoimmune disorders owing to their multilineage differentiation and immunomodulatory capacities, respectively. One advantage of ASC-based therapy lies in their immunosuppressive potential. However, how to get ASCs to provide consistent immunosuppression remains unclear. In the current study, we found that miR-129-5p was induced in ASCs treated with inflammatory factors. ASCs with miR-129-5p knockdown exhibited enhanced immunosuppressive capacity, as evidenced by reduced expression of proinflammatory factors, with concurrent increased expression of inducible nitric oxide synthases (iNOS) and nitric oxide (NO) production. These cells also had an increased capacity to inhibit T cell proliferation in vitro. ASCs with miR-129-5p knockdown alleviated inflammatory bowel diseases and promoted tumor growth in vivo. Consistently, ASCs that overexpressed miR-129-5p exhibited reduced iNOS expression. Furthermore, we show that miR-129-5p knockdown in ASCs results in hyperphosphorylation of signal transducer and activator of transcription 1 (Stat1). When fludarabine, an inhibitor of Stat1 activation, was added to ASCs with miR-129-5p knockdown, iNOS mRNA and protein levels were significantly reduced. Collectively, these results reveal a new role for miR-129-5p in regulating the immunomodulatory activities of ASCs by targeting Stat1 activation. These novel insights into the mechanisms of ASC immunoregulation may lead to the consistent production of ASCs with strong immunosuppressive functions and thus better clinical utility of these cells.

14.
ChemMedChem ; 14(24): 2042-2051, 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31746558

RESUMO

Herein we describe a focused set of new arylpiperazine derivatives as potential broad-spectrum antipsychotics. The general structure contains a quinolinone-like moiety, an arylpiperazine moiety, and a five-atom linker. Among them, 7-(5-(4-(benzo[d]isothiazol-4-yl)piperazin-1-yl)pentyl)quinolin-2(1H)-one (S6) shows a promising preclinical profile. Compound S6, characterized by partial D2 R agonism, 5-HT1A R agonism, 5-HT2A R antagonism, and blockade of SERT activities, was found to decrease psychosis- and depressive-like symptoms in rodents. The polypharmacological profile of S6 could provide opportunities for the treatment of various other central nervous system disorders such as anxiety, depression, and psychoses associated with dementia. Furthermore, S6 demonstrated acceptable safety, toxicology, and pharmacokinetic profiles, and has been selected as a preclinical candidate for further evaluation in schizophrenia.

15.
Microorganisms ; 7(11)2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31752202

RESUMO

The composition of the bacterial community affects the intestinal health and growth performance of broiler chickens. The main purpose of this study was to explore the effects of flavomycin and colistin sulfate on the resistance to Salmonella typhimurium infection, ileal bacteria and intestinal health. In total, 396 1-day-old broiler chickens were randomly divided into six groups. Two groups were fed each one of the diets-the control diet (CON), the flavomycin at 10 mg/kg diet (AntiG+), and the colistin sulfate at 40 mg/kg diet (AntiG-), for 5 days. Then, one of each of the two groups was challenged with S. typhimurium on the 8th day; these were named CONS, AntiG+S and AntiG-S, respectively. The results showed that S. typhimurium significantly reduced the feed intake and body weight gain, and increased the feed conversion ratio (p < 0.05). It also increased the inflammatory expressions of NF-κB and MyD88 genes (p < 0.05); and reduced the expressions of claudin-1, occludin and mucin-2 (p < 0.05) tight junction genes in the intestines. S. typhimurium significantly reduced ileal bacterial diversity indexes of observed-species, chao1 and Shannon (p < 0.05). Compared with AntiG+S group, AntiG-S group increased the body weight gain of broiler chickens (p < 0.05), reduced the expression of inflammatory genes (p < 0.05) and intestinal permeability to fluorescein isothiocyanate (p < 0.05). AntiG-S group also improved the ileal bacterial diversity indexes of observed-species and Shannon (p < 0.05). There were many significant correlations between intestinal bacteria, intestinal gene expressions and intestinal morphology (p < 0.05). This study indicated that pre-constructed AntiG- bacteria could against a S. typhimurium infection by inhibiting the expressions of intestinal inflammation genes and increasing the diversity of intestinal bacteria.

16.
Cell Tissue Res ; 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31736014

RESUMO

The article "Reducing macrophage numbers alleviates temporomandibular joint ankylosis", written by Lu Zhao, E Xiao, Linhai He, Denghui Duan, Yang He, Shuo Chen, Yi Zhang and Yehua Gan, was originally published electronically on the publisher's internet portal.

17.
Breast Cancer ; 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31781983

RESUMO

BACKGROUND: Multiple studies have indicated that albendazole (ABZ) can disrupt the microtubule in worms and have anti-tumor potential in a variety of tumors. However, the therapeutic effect of ABZ on triple-negative breast cancer (TNBC) is largely unknown, and the therapeutic evaluation of ABZ by 18F-FDG PET imaging remains relatively unexplored. METHODS: The effects of ABZ on TNBC cell lines (MDA-MB-231 cells) were investigated in vitro using MTT, wound-healing, transwell migration, flow cytometry and Western blotting analyses. In vivo treatment was conducted in an MDA-MB-231 tumor-bearing nude mouse model. Mouse body weight loss was also evaluated. PET imaging was performed before and after 3 days of treatment. Tumor tissues were harvested for immunofluorescence analysis. RESULTS: ABZ treatment inhibited the proliferation and migration and triggered the apoptosis in MDA-MB-231 cells. Furthermore, Western blotting analysis showed that ABZ induced the apoptosis in MDA-MB-231 cells via GLUT1/AMPK/P53 signaling pathway. Long-term treatment studies found that the tumor volume of the treatment group was smaller compared with the control group, and the survival time was prolonged. In vivo 18F-FDG PET imaging showed that 3-day ABZ treatment reduced standardized uptake value (SUV) values in MDA-MB-231 xenografts compared with the controls, and immunofluorescence analysis showed more TUNEL-positive cells in the ABZ-treated mice. CONCLUSIONS: Our study suggested that ABZ induced the apoptosis of MDA-MB-231 cells by inhibiting glucose uptake, and it could be considered as a potential drug for TNBC cells. Moreover, 18F-FDG PET imaging could be used to monitor the early anti-tumor effect of ABZ on MDA-MB-231 tumors.

18.
Microorganisms ; 7(10)2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31581417

RESUMO

The objective of this study was to explore whether collecting rumen samples of finishing steers at monthly intervals differed, and whether this difference or similarity varied with diets. For these purposes, 12 Chinese Holstein steers were equally divided into two groups. The dietary treatments were either standard energy and standard protein (C) or low energy and low protein (L). Rumen samples were obtained on day 30, day 60 and day 90 from both dietary treatments and were analyzed by using 16S rRNA gene sequencing. The results showed that monthly intervals had no effect on the richness and evenness of the rumen bacterial community in the two diets. However, taxonomic difference analysis (relative abundance >0.5%) revealed that the relative abundance of three phyla (Proteobacteria, Fibrobacteres and Cyanobacteria) and six genera (Rikenellaceae_RC9_gut_group, Ruminococcaceae_NK4A214_group, Fibrobacter, Eubacterium_coprostanoligenes_group, Ruminococcaceae_UCG-010 and Ruminobacter) were significantly different between monthly sampling intervals, and the difference was prominent between sampling in the first month and the subsequent two months. Moreover, the differences in abundances of phyla and genera between monthly sampling intervals were affected by diets. Analysis of similarity (ANOSIM) showed no significant differences between monthly sampling intervals in the C diet. However, ANOSIM results revealed that significant differences between the first month and second month and between the first month and third month were present in the L diet. These results indicated that temporal dynamics in rumen bacterial community composition did occur even after an adaptation period of three months. This study tracked the changes in rumen bacterial populations of finishing cattle after a shift in diet with the passage of time. This study may provide insight into bacterial adaptation time to dietary transition in finishing steers.

19.
Environ Nanotechnol Monit Manag ; 11: 1-100204, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31583199

RESUMO

The goal of the present paper is to develop chemometrics-based multivariate calibration approaches for simultaneously determining quantity of individual carbon nanotubes (CNTs) in a multicomponent environmental matrix using a microwave induced heating method. A multifactor and multilevel experiment design was used to create 4 separate calibration datasets. Each calibration dataset contained 25 orthogonal CNTs with 2 or 3 factors (CNTs: single-walled CNTs (SWCNTs)/multi-walled CNTs (MWCNTs)/carboxylated MWCNTs (MWCNT-COOH)) and 5 levels (CNTs mass). The temperature rise (ΔT) spectral information was obtained for each sample by exposing to varying microwave conditions. This study showed the potential and applicability of partial least square regression (PLS), least square-support vector machine (LS-SVM) and artificial neural networks (ANN) in predicting quantities of SWCNTs, MWCNTs and MWCNT-COOH in environmental matrices with microwave induced temperature rises data. Our results revealed that the developed LS-SVM model presented higher R2 and lower root mean square error of prediction (RMSEP) (R2 = 0.74-0.93, RMSEP =0.0251 mg to 0.0328 mg in 2-component systems and R2 = 0.64-0.95, RMSEP = 0.0243 mg to 0.0410 mg in 3-component systems), while the ANN model was only accurate in estimating mass of SWCNT and MWCNT in a 2-component mixture (R2 = 0.77-0.89, RMSEP = 0.0322 mg to 0.0503 mg). The PLS model was found not effectively interpret relationship between microwave induced temperature rises data and mass of CNTs, indicated by small R2 (0.20-0.87) and large RMSEP (0.0209 mg -0.1021 mg).

20.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(5): 1402-1408, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31607290

RESUMO

OBJECTIVE: To investigate the mechanism of rapamycin-induced apoptosis of chronic myelogenous leukemia cells. METHODS: The chronic granulocytic leukemia K562 cells were divided into 3 groups: A, B and C group were treated with rapamycin of 10, 15 and 20 nmol/L, repectively for 24 h, while the K562 cells in control group were not treated with rapamycin. The effect of rapamycin on the proliferation of K562 cells was detected by MTT, and the effect of rapamycin on the apoptosis of K562 cells was detected by AnnexinV-FITC/PI double staining. The expression level of EZH2/Hedgehog signaling pathway genes in K562 cells was detected by RT-PCR, and Western blot was used to detect the levels of apoptotic protein and the related signaling pathway proteins in K562 cells. RESULTS: The MTT assay showed that the different concentration of rapamycin had obvious inhibitory effects on the cells, and the survival rate of cells in group C was 37.6%±3.4%, which was significantly lower than that of the other groups (P<0.05). The apoptosis rate of cells in group C was 93.1%±8.1%, which was significantly higher than that of the other groups (P<0.05). By Western blot, it was found that the relative expression levels of Caspase-3 and BAX protein in group C were 0.36 ± 0.04 and 0.39±0.06, respectively, which were significantly higher than those in other groups (P<0.05), and the level of BCL-2 protein was 0.17±0.03, which was significantly lower than that of other groups (P<0.05). By RT-PCR, it was found that the mRNA levels of EZH2 and Hedgehog genes in A, B and C groups were significantly lower than those in the control group (P<0.05), but mRNA level of Ptch1 gene was significantly higher than that of the control (P<0.05). By Western blot, it was found that the expression levels of EZH2 and Hedgehog protein in A, B and C groups were significantly lower than that in the control group (P<0.05), but the level of Ptch1 protein was higher than that of the control (P<0.05). The relative levels of EZH2 and Hedgehog protein in group C were 0.21 ±0.03 and 0.16±0.05 respectively, which were significantly lower than those in other groups (P<0.05), and Ptch1 protein level were 0.46 ±0.06, significantly higher than that of other groups (P<0.05). CONCLUSION: Rapamycin can inhibit the protein expression of EZH2 in leukemic cells, thus interfere with the activation of Hedgehog signaling pathway, promote the expression of apoptotic protein, reduce the level of anti apoptotic protein, and eventually induce apoptosis of leukemia cells.


Assuntos
Transdução de Sinais/efeitos dos fármacos , Apoptose , Proliferação de Células , Proteína Potenciadora do Homólogo 2 de Zeste , Proteínas Hedgehog , Humanos , Células K562 , Sirolimo
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