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1.
J Cell Biochem ; 121(1): 876-887, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31452262

RESUMO

The oncogenesis and progression of gastric cancer are closely correlated with the complex regulatory relationships among messenger RNA (mRNA), long noncoding RNA (lncRNA), and microRNA (miRNA). After constructing the gastric cancer lncRNA-miRNA-mRNA regulatory network, we analyzed the network topology properties and found that lncRNA ADAMTS9-AS2 and C20orf166-AS1 and miRNA hsa-mir-204 are key nodes. Further functional enrichment analysis and survival analysis were performed on these key nodes and the RNAs interacting with them. We found that CHRM2, ANGPT2, and COL1A1 interacting with ADAMTS9-AS2 are enriched in the PI3K-Akt signaling pathway, and low expression of the ADAMTS9-AS2 is closely related to the prognosis of patients. Abnormal expression of CACNA1H, FLNA, and FLNC interacting with lncRNA C20orf166-AS1 is associated with MAPK signaling pathway in gastric cancer. In addition, the downregulated miRNA hsa-mir-204 promotes invasion and proliferation of gastric cancer cells by regulating the abnormal expression of mRNAs (CHRDL1 and NPTX1) and lncRNAs (ADAMTS9-AS2, NKX2-1-AS1, TLR8-AS1, and VCAN-AS1). This study systematically analyzed the lncRNA-miRNA-mRNA regulatory network of gastric cancer, which not only has a new understanding of the pathogenesis of gastric cancer, but also provides new insights for the early diagnosis and treatment of gastric cancer.

2.
Adv Exp Med Biol ; 1179: 17-37, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31741332

RESUMO

Chronic hepatitis B virus (HBV) infection remains to be a serious threat to public health and is associated with many liver diseases including chronic hepatitis B (CHB), liver cirrhosis, and hepatocellular carcinoma. Although nucleos(t)ide analogues (NA) and pegylated interferon-α (Peg-IFNα) have been confirmed to be efficient in inhibiting HBV replication, it is difficult to eradicate HBV and achieve the clinical cure of CHB. Therefore, long-term therapy has been recommended to CHB treatment under the current antiviral therapy. In this context, the new antiviral therapy targeting one or multiple critical steps of viral life cycle may be an alternative approach in future. In the last decade, the functional receptor [sodium-taurocholate cotransporting polypeptide (NTCP)] of HBV entry into hepatocytes has been discovered, and the immature nucleocapsids containing the non- or partially reverse-transcribed pregenomic RNA, the nucleocapsids containing double-strand linear DNA (dslDNA), and the empty particles devoid of any HBV nucleic acid have been found to be released into circulation, which have supplemented the life cycle of HBV. The understanding of HBV life cycle may offer a new instruction for searching the potential antiviral targets, and the new viral markers used to monitor the efficacy of antiviral therapy for CHB patients in the future.


Assuntos
Antivirais , Vírus da Hepatite B , Hepatite B Crônica , Antivirais/farmacologia , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/genética , Vírus da Hepatite B/crescimento & desenvolvimento , Hepatite B Crônica/virologia , Hepatócitos/virologia , Humanos , Interferon-alfa/farmacologia , Internalização do Vírus/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
3.
Gene ; 724: 144144, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31629819

RESUMO

BACKGROUND/AIMS: Rheumatoid arthritis synovial fibroblasts (RASF) play an essential role in the pathogenesis of rheumatoid arthritis (RA). This study aimed to investigate the biological effects of miR-22 on RASFs. METHODS: RT-qPCR was used to detect the expressions of miR-22 and SIRT1 in RA synovial tissue. The results of miR-22 on the proliferation of RASF were examined by MTT assay. The effects of miR-22 on the secretion of TNF-α, IL-1ß, and IL-6 in RASF were measured by ELISA. Target gene prediction and screening, and luciferase reporter assay were used to testify downstream target genes of miR-22. RT-qPCR and western blotting were used to detect the mRNA and protein expression of SIRT1. RESULTS: miR-22 was significantly decreased in RA synovial tissue, while SIRT1 was significantly increased in RA synovial tissue. Over-expression of miR-22 significantly inhibited the proliferation of RASFs and the secretions of inflammatory cytokines (TNF-α, IL-1ß, and IL-6) in RASFs. SIRT1 was identified as a direct target of miR-22. Over-expression of miR-22 reduced the expression level of SIRT1 in RASFs. Over-expression of SIRT1 reversed the effect of miR-22 on the proliferation of RASFs and the secretion of inflammatory cytokines. CONCLUSION: MIR-22 was significantly down-regulated in RASF cells, which affected the secretions of inflammatory cytokines and cell proliferation by regulating SIRT1.

4.
J Proteomics ; 210: 103527, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31610263

RESUMO

Bombyx mori nucleopolyhedrovirus (BmNPV) is a major pathogen causing severe economic loss. Previous studies have revealed that some proteins in silkworm digestive juice show antiviral activity. In this study, antiviral activity examination of different resistant strains showed that the digestive juice of the resistant strain (A35) had higher inhibition to virus than the susceptible strain (P50). Subsequently, the label-free quantitative proteomics was used to study the midgut digestive juice response to BmNPV infection in P50 and A35 strains. A total of 98 proteins were identified, of which 80 were differentially expressed proteins (DEPs) with 54 enzymes and 26 nonenzymatic proteins by comparing the proteomes of infected and non-infected P50 and A35 silkworms. These DEPs are mainly involved in metabolism, proteolysis, neuroactive ligand receptor interaction, starch and sucrose metabolism and glutathione metabolism. After removing the genetic background and individual immune stress response proteins, 9 DEPs were identified potentially involved in resistance to BmNPV. Further studies showed that a serine protease, an alkaline phosphatase and serine protease inhibitor 2 isoform X1 were differentially expressed in A35 compared to P50 or post BmNPV infection. Taken together, these results provide insights into the potential mechanisms for silkworm digestive juice to provide resistance to BmNPV infection. Signifcance: Bombyx mori nucleopolyhedrovirus (BmNPV) is highly pathogenic, which has a great impact on the sericulture. BmNPV entered the midgut lumen and exposed to digestive juices after oral infection. Previous studies have revealed that some proteins in silkworm digestive juice show antiviral activity, however, current information on the digestive juice proteome of high resistant silkworm strain after BmNPV challenge compared to susceptible strain is incomprehensive. Here, we combined label-free quantification method, bioinformatics, RT-qPCR and western blot analysis and found that BmNPV infection causes some protein changes in the silkworm midgut digestive juice. The DEPs were identified in the digestive juices of different resistant strains following BmNPV infection, and screened out some proteins potentially related to resistance to BmNPV. Three important differentially expression proteins were validated by independent approaches. These findings uncover the potential role of silkworm digestive juice in providing resistance to BmNPV and supplemented the profile of the proteome of the digestive juices in B. mori.

5.
J Nanosci Nanotechnol ; 20(4): 2514-2520, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492270

RESUMO

Graphene has excellent conductivity and can thus serve as an electrical conductivity network. In this study, graphene-modified core-shell NiO/C composites were successfully synthesized. The connections among NiO/C particles were enhanced by shock cooling the link of each porous NiO/C particle. SEM and TEM images were obtained, which showed that the resulting core-shell NiO/C composites were rolled in graphene and evenly distributed. As anode material for Li-ion batteries, the discharge capacity for the 100th cycle is maintained at 637.6 mAh g-1. When the increase in current density increases was constant, the discharge capacity did not plummet, and the cycle was stable. When the current density increased to 800 mA g-1 ad then decreased to 100 mA g-1, the discharge capacity increased to 623.1 mAh g-1, which reflects an outstanding rate performance.

6.
Chemosphere ; 240: 124965, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31726610

RESUMO

To investigate the effects of spatial expansion between native invasive species (Phragmites australis) and commom native species (Cyperus malaccensis) on variations of micro-elements (Pb, Cr, Cu, Zn, Ni, Cd and As) in decomposing litters in the Min River estuary, in situ filed decomposition experiment was conducted in P. australis (PA) community (before expansion, BE), C. malaccensis (CM) community (before expansion, BE) and P. australis-C. malaccensis (PA'-CM') community (during expansion, DE) from February 2016 to February 2017 by space-for- time substitution method. Results showed that the decomposition of C. malaccensis were faster than those of P. australis whether at BE stage or at DE stage. The decomposition rate of PA' increased by 24.40% compared to PA whereas the value of CM' decreased by 15.67% compared with CM. The concentrations of Pb, Cu, Zn, Ni, Cd and As in decomposing litters of P. australis (PA and PA') and C. malaccensis (CM and CM') generally showed increasing tendency and the values in the former were significantly lower than those in the latter (p < 0.05). The physicochemical sorption onto recalcitrant organic fractions and the substrate quality (C/N and M/C ratios) of decomposing litters were two important factors affecting the differences in As/metals variations between species. The levels of Cr in decaying litters increased initially and decreased afterward, and the values in P. australis were significantly higher than those in C. malaccensis (p < 0.05). Whether at BE stage or at DE stage, stocks of As/metals in decomposing litters of P. australis (PA and PA') were generally higher than those of C. malaccensis (CM and CM'). The lower stocks of As/metals in CM or CM' might be more dependent on its lower mass remaining. Compared with PA at BE stage, the accumulation of As/metals in decomposing litters of PA' at DE stage decreased greatly, which might be ascribed to the lower precipitation of metal sulfides in PA'. Stocks of Zn, Ni, Cd and Cr in CM' and stocks of Cr in PA' generally evidenced the export of metals from decomposing litter to environment, indicating that the potential exposure risk of Zn, Ni, Cd and Cr might be increased as CM was invading by PA. This study found that the spatial expansion between P. australis and C. malaccensis not only altered the stocks of As/metals in decomposing litters but also increased the exposure risk of Zn, Ni, Cd and Cr in ecotone. In future, as the ecological functions of ecotone was precisely evaluated during the expansion of the two plants in the Min River estuary, the alterations of litter decomposition rates and the exposure risks of Zn, Ni and Cd caused by CM' should be emphasized.

7.
J Cell Physiol ; 235(2): 932-943, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31236965

RESUMO

Histone demethylase KDM7A regulates neuronal differentiation and development in mammals. In this study, we found that KDM7A was also required for breast cancer stem cells (BCSCs) maintenance. Silencing KDM7A significantly reduced the BCSCs population and mamosphere formation in vitro, and inhibited breast tumor growth in vivo. Restoring KDM7A expression rescued the defect in stem cell maintenance. Our mechanism analysis suggested that KDM7A upregulated the stemness-associated factors KLF4 and c-MYC for BCSCs maintenance. In addition, KDM7A knockdown promoted apoptosis through decreasing BCL2 expression and BAD phosphorylation in breast cancer (BrCa). Furthermore, restoring KDM7A and BCL2 expression rescued apoptosis inhibition in breast cancer, suggesting that KDM7A inhibited apoptosis by upregulating the BCL2 level in breast cancer. In conclusion, KDM7A promotes cancer stem cell maintenance and apoptosis inhibition in breast cancer.

8.
J Colloid Interface Sci ; 559: 105-114, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31614315

RESUMO

Exploring highly-efficient, low-cost and earth-abundant bi-functional electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) have a key role in economical overall water-splitting. Herein, a facile and general route is developed to prepare various non-noble metal-based electrocatalysts via NH3⋅H2O treatment (NT) on Ni foam (NF) (M-NT/NF, M = Co, Ni, Fe, Mn, Cu). The morphology and compositions of the obtained catalysts could be tuned via solvothermal process with NH3⋅H2O, and then optimizing the active sites exposure and effectively change the reaction kinetics of the electrocatalytic reaction. Moreover, the substrate of Ni foam is in favor of electrolyte transfer and release of produced gases. Then, the obtain Co-NT/NF, composed of metallic Co and Co(OH)2, exhibits excellent catalytic performance for HER with low overpotential of 178 mV@10 mA cm-2 and small Tafel slope of 75 mV dec-1, which is rarely reported for HER. For OER, only a low overpotential of 226 mV is required to deliver 10 mA cm-2 with a small Tafel slope of 46 mV dec-1. Moreover, the reported electrocatalysts present negligible current density loss during long-term stability measurement, demonstrating robust nanostructure feature of the prepared catalysts. This work opens a facile and efficient avenue to design bi-funtional electrocatalyst coupling with outstanding catalytic performance.

9.
Cancer Immunol Res ; 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31719056

RESUMO

T-cell receptor (TCR)-based biomarkers might predict patient response to immune checkpoint blockade (ICB), but need further exploration and validation for that use. We sequenced complementarity-determining region 3 of TCRß chains isolated from PD-1+ CD8+ T cells to investigate its value for predicting the response to anti-PD-1/PD- ligand 1 (PD-L1) therapy in patients with non-small cell lung cancer (NSCLC). Two independent patient cohorts (cohorts A, n=25; cohort B, n=15) were used as discovery and validation sets, respectively. Pre- and post-ICB peripheral blood samples were collected. In cohort A, patients with high PD-1+ CD8+ TCR diversity pre-ICB showed better response to ICB and progression-free survival (PFS) compared to patients with low diversity [6.4 months vs. 2.5 months, hazard ratio (HR), 0.39, 95% confidence interval (CI), 0.17-0.94, P=0.021]. The results were validated in cohort B. Pre-ICB PD-1+ CD8+ TCR diversity achieved an optimal Youden's index of 0.81 (sensitivity = 0.87 and specificity = 0.94) for differentiating the ICB response in the merged dataset (cohort A plus cohort B). Patients with increased PD-1+ CD8+ TCR clonality after ICB treatment had longer PFS (7.3 months vs. 2.6 months, HR, 0.26, 95% CI, 0.08-0.86, P=0.002) than those with decreased clonality. Thus, TCR diversity and clonality in peripheral blood PD-1+ CD8+ T cells may serve as noninvasive predictors of patient response to ICB and survival outcomes in NSCLC.

10.
BMC Genomics ; 20(1): 810, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31694527

RESUMO

BACKGROUND: Brassinosteroids (BRs) have a positive effect on many processes during plant growth and development, and in response to various abiotic stressors. Low-temperature (LT) stress constricts the geographic distribution, growth, and development of wucai (Brassica campestris L. ssp. chinensis var. rosularis Tsen). However, there is little information on the global gene expression of BRs under LT stress in wucai. In this study, the molecular roles of 24-epibrassinolide (EBR) after exogenously application, were explored by RNA sequencing under LT conditions. RESULTS: According to the Gene Ontology (GO) term and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses, photosynthesis was significantly enriched after spraying EBR under LT. The transcripts encoding the photosystem II (PSII) oxygen-evolving enhancer protein, photosystem I (PSI) subunit, light-harvesting chlorophyll protein complexes I and II, and ferredoxin were up-regulated after the application of EBR. Transcripts encoding several key enzymes involved in chlorophyll biosynthesis were also up-regulated, accompanied by significant differences in the contents of 5-aminolevulinic acid (ALA), porphobilinogen (PBG), protoporphyrin IX (Proto IX), Mg-protoporphyrin IX (Mg-proto IX), protochlorophyllide (Pchl), and photosynthetic pigments. Notably, transcriptional and physiological analyses revealed that under LT stress, plant responses to EBR involved a major reorientation of photosynthesis, as well as porphyrin and chlorophyll metabolism. CONCLUSION: This study explored the role of EBR as an LT stress tolerance mechanism in wucai. At the transcription level, LT tolerance manifests as an enhancement of photosynthesis, and the amelioration of porphyrin and chlorophyll metabolism.

11.
Medicine (Baltimore) ; 98(44): e17661, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31689777

RESUMO

RATIONALE: Primary Extranodal Natural Killer/T-Cell Nasal-Type Lymphoma (ENKTCL) of spine is rarely reported. This case study presents a rare case of ENKTCL originating from the sixth thoracic vertebra. PATIENT CONCERNS: Here, we present a case of 49-year-old Asian male with chest and back pain. Physical examination revealed the myodynamia of both lower limbs decreased from IV degree to 0 degree, reflexes of both lower limbs and a large area of cutaneous sensation below xiphoid process disappeared in 3 days. DIAGNOSES: In immunophenotype analysis, CD2, CD3, CD7, and CD68 were positive and CD56 was suspiciously positive. Granzyme B and T-cell intracellular antigen (TIA-1) were also positive and in situ hybridization was positive for Epstein-Barr virus-encoded mRNA (EBER). Ki-67 was 60%+. Nuclide bone scan showed that the nuclide was unusually concentrated in the sixth thoracic vertebra which considered extremely active and slightly concentrated in the right sacrolilac joint. Magnetic resonance imaging detected an abnormal signal in the sixth thoracic vertebra with corresponding paravertebral and intraspinal occupying lesion. Based on the above features, a diagnosis of ENKTCL was made. INTERVENTIONS: This patient was treated with surgery and symptomatic supportive treatment. OUTCOMES: The myodynamia of patient's both lower limbs were elevated to I degree after the operation with chest and back pain partly relieved. However, the patient died about 3 months later. LESSONS: ENKTCL could originate from spine. Clinicians should be alert for early stage diagnose and distinguish it from some common spinal tumor such as neurofibroma and hemangioma.

12.
Macromol Rapid Commun ; : e1900516, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31692166

RESUMO

Although a variety of biomimetic mineralized materials have been created in the lab, the vast majority of these manmade examples lack response to external stimuli. Here, mineralized supramolecular hydrogels with on-demand thermo-responsiveness that are formed by a simple, physical crosslinking between amorphous CaCO3 (ACC) nanoparticles and poly(acrylic acid) (PAA) are reported. Upon the addition of Na2 CO3 solution into a mixture composed of PAA and CaCl2 , amorphous ACC nanoparticles are formed in situ and simultaneously crosslinked by PAA chains, giving rise to the mineralized hydrogels. Interestingly, upon tuning the content of the formed ACC, hydrogels with different types of thermo-responsiveness can be easily obtained, and the transparencies of the resulting hydrogels are dramatically changed during the temperature-driven phase transitions. As an application, these thermo-responsive mineralized hydrogels are used to control the exposure of UV light, which is successfully applied to switch fluorescent signals in response to temperature.

13.
Molecules ; 24(21)2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31671660

RESUMO

Many dyes and pigments are used in textile and printing industries, and their wastewater has been classed as a top source of pollution. Biodegradation of dyes by fungal laccase has great potential. In this work, the influence of reaction time, pH, temperature, dye concentration, metal ions, and mediators on laccase-catalyzed Remazol Brilliant Blue R dye (RBBR) decolorization were investigated in vitro using crude laccase from the white-rot fungus Ganoderma lucidum. The optimal decolorization percentage (50.3%) was achieved at 35 °C, pH 4.0, and 200 ppm RBBR in 30 min. The mediator effects from syringaldehyde, 1-hydroxybenzotriazole, and vanillin were compared, and 0.1 mM vanillin was found to obviously increase the decolorization percentage of RBBR to 98.7%. Laccase-mediated decolorization percentages significantly increased in the presence of 5 mM Na+ and Cu2+, and decolorization percentages reached 62.4% and 62.2%, respectively. Real-time fluorescence-quantitative PCR (RT-PCR) and protein mass spectrometry results showed that among the 15 laccase isoenzyme genes, Glac1 was the main laccase-contributing gene, contributing the most to the laccase enzyme activity and decolorization process. These results also indicate that under optimal conditions, G. lucidum laccases, especially Glac1, have a strong potential to remove RBBR from reactive dye effluent.

14.
Artigo em Inglês | MEDLINE | ID: mdl-31754765

RESUMO

Currently, knowledge of circular RNAs (circRNAs) in insects including honeybee is extremely limited. Here, differential expression profiles and regulatory networks of circRNAs in the midguts of Apis cerana cerana workers were comprehensively investigated using transcriptome sequencing and bioinformatics. In total, 9589 circRNAs (201-800 nt in length) were identified from 8-day-old and 11-day-old workers' midguts (Ac1 and Ac2); among them, 5916 (61.70%) A. cerana cerana circRNAs showed conservation with our previously indentified circRNAs in Apis mellifera ligucstica workers' midguts (Xiong et al., Acta Entomologica Sinica 61:1363-1375, 2018). Five circRNAs were confirmed by RT-PCR and Sanger sequencing. Interestingly, novel_circ_003723, novel_circ_002714, novel_circ_002451, and novel_circ_001980 were highly expressed in both Ac1 and Ac2. In addition, the source genes of circRNAs were involved in 34 GO terms including organelle and cellular process and 141 pathways such as endocytosis and Wnt signaling pathway. Moreover, 55 DEcircRNAs including 34 upregulated and 21 downregulated circRNAs were identified in Ac2 compared with Ac1. circRNA-miRNA regulatory networks indicated that 1060 circRNAs can target 74 miRNAs; additionally, the DEcircRNA-miRNA-mRNA networks suggested that 13 downregulated circRNAs can bind to eight miRNAs and 29 miRNA-targeted mRNAs, while 16 upregulated circRNAs can link to 9 miRNAs and 29 miRNA-targeted mRNAs. These results indicated that DEcircRNAs as ceRNAs may play a comprehensive role in the growth, development, and metabolism of the worker's midgut via regulating source genes and interacting with miRNAs. Notably, eight DEcircRNAs targeting miR-6001-y were likely to be key participants in the midgut development. Our findings not only offer a valuable resource for further studies on A. cerana cerana circRNA and novel insights into understanding the molecular mechanisms underlying the midgut development of eastern honeybee but also provide putative circRNA candidates for functional research in the near future and novel biomarkers for identification of eastern honeybee species including A. cerana cerana and honeybee diseases such as chalkbrood and microsporidiosis.

15.
J Org Chem ; 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31755261

RESUMO

The Diels-Alder (DA) reaction strategy that can rapidly extend the conjugated backbone was applied to facilely synthesize fold-line, coplanar BN-embedded polycyclic aromatic hydrocarbons (PAHs) from simple small BN compounds. The molecular structures and packing modes of these BN-embedded acenes were confirmed by single crystal X-ray diffraction. Their electronic and photophysical properties were studied by using UV-vis, fluorescence spectroscopy, electrochemical cyclic voltammetry, and density functional theory (DFT) calculation. These results demonstrate the efficiency and feasibility of this synthetic strategy.

16.
Peptides ; 123: 170200, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31730792

RESUMO

Apoptosis induced by oxidative stress is one of the most important cardiomyocytes losses during ischemia-reperfusion (I/R). Catestatin (CST) has been demonstrated to have the anti-oxidative capacity in vitro. We hypothesized that CST intervention could reduce apoptosis of cardiomyocytes induced by oxidative stress in I/R. In Langendorff-perfused rat heart global I/R model, CST was introduced at the reperfusion stage. In comparison to the control group, CST led to preservation on activities of superoxide dismutase and glutathione peroxidase, improvement of hemodynamics, and reduced infarction area in reperfused myocardium. The protection of CST was also shown by less apoptotic cardiomyocytes in TUNEL staining, less caspase-3 activation, and increased phosphorylation of protein kinase B (PKB/Akt) in Western blot. To further demonstrate the benefits of CST and explore the possible underlying mechanism, H2O2-challenged primary-cultured neonatal rat cardiomyocytes were used to simulate the oxidative-stressed scenario. CST incubation with the H2O2-challenged cardiomyocytes led to reduction of apoptosis, which was demonstrated by less Hoechst 33342 positive staining of nuclei, less caspase-3 activation, and DNA fragmentation. The effect of CST was abrogated by pretreatment of the cardiomyocytes with the PI3K inhibitor LY294002. Furthermore, Akt activation and the anti-apoptosis effect of CST were abolished by pretreatment of the cardiomyocytes with ß2 receptor inhibitor ICI118551. Thus, the salvage of oxidative-stress-induced apoptotic cardiomyocytes in I/R by CST might involve activation ß2 receptor and regulation of PI3K/Akt signaling in reperfusion injury salvage kinase (RISK) pathway.

17.
J Org Chem ; 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31671948

RESUMO

Highly efficient alkylation of ß-chloro ketones and their derivatives was achieved by means of domino dehydrochlorination/Mn-enabled radical-based alkyl-alkyl cross-coupling reaction. In situ-generated α,ß-unsaturated ketones and their analogues were identified as the reaction intermediates. Known bioactive compounds, such as melperone and azaperone, could be easily prepared from ß-chloropropiophenone in two steps.

18.
World J Gastroenterol ; 25(41): 6190-6204, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31745380

RESUMO

BACKGROUND: Acute liver failure (ALF) is a significant and complex hepatic insult that may rapidly progress to life-threatening conditions. Recently, menstrual blood stem cells (MenSCs) have been identified as a group of easily accessible mesenchymal stem cells with the advantages of non-invasive acquisition, low immunogenicity, a greater capacity of self-renewal and multi-lineage differentiation, making them promising candidates for stem cell-based therapy to revolutionize the treatment strategies for liver failure. AIM: To investigate the therapeutic potential of MenSCs for treating ALF in pigs and to dynamically trace the biodistribution of transplanted cells. METHODS: MenSCs were labeled in vitro with PKH26, a lipophilic fluorescent dye. The treatment group received immediate transplantation of PKH26-labelled MenSCs (2.5 × 106/kg) via the portal vein after D-galactosamine injection, and the control group underwent sham operation. The survival time, liver function, and hepatic pathological changes were compared between the two groups. Three major organs (liver, lungs and spleen) were extracted from animals and imaged directly with the In vivo Imaging System (IVIS) at the predetermined time points. The regions of interest were drawn to quantify the cell uptake in different organs. RESULTS: The labelling procedure did not affect the morphology, viability or multipotential differentiation of MenSCs. Biochemical analysis showed that the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TBIL) and prothrombin time (PT) measured at selected time points 24 h after transplantation were significantly decreased in the treatment group (P < 0.05). The survival time of ALF animals was prolonged in the treatment group compared with the control group (75.75 ± 5.11 h vs 53.75 ± 2.37 h, log rank, P < 0.001). The liver pathological tissue in the MenSC treatment group showed obviously increased numbers of remaining hepatocytes and a comparatively slight necrotic degree and area. In addition, the IVIS imaging revealed that PKH26-positive MenSCs were clearly retained in the liver initially and then diffused through the systemic circulation. Interestingly, the signal intensity in the liver increased obviously at 36 h, which corresponded to the biochemical result that liver function deteriorated most rapidly at 24 - 36 h. CONCLUSION: Our study demonstrates the therapeutic efficacy and homing ability of transplanted MenSCs in a large animal model of ALF and suggests that MenSC transplantation could be a promising strategy for treating ALF.

19.
Can J Microbiol ; 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31751146

RESUMO

Lipopolysaccharide (LPS) is essential for successful nodulation during the symbiosis of rhizobia and legumes. However, the detailed mechanism of the LPS in this process has not yet been clearly elucidated. In this study, the effects of exudates the common bean seeds on the growth, lipopolysaccharide production and lipopolysaccharide transport genes expression (lpt) of Rhizobium anhuiense were investigated. R. anhuiense exposed to exudates showed changes in LPS electrophoretic profiles and content, where the LPS band was wider and the LPS content was higher in R. anhuiense treated with seeds exudates. Exudates enhanced cell growth of R. anhuiense in a concentration dependent manner; R. anhuiense exposed to higher doses of the exudate showed faster growth. Seven ltp genes of R. anhuiense were amplified and sequenced. Sequences of six lpt genes, except for lptE, were the same as found in previously analyzed R. anhuiense strains, while lptE shared low sequence similarity with other strains. Exposure to the exudates strongly stimulated the expression of all lpt genes. An approximately 6.7- (lptG) to 301-fold (lptE) increase in the transcriptional levels were observed after only 15 min of exposure to exudates. These results indicate that seed exudates affect the LPS by making the cell wall structure more conducive to symbiotic nodulation.

20.
Chem Commun (Camb) ; 55(95): 14359-14362, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31720593

RESUMO

Human islet amyloid polypeptide (hIAPP) oligomers are transient due to rapid aggregation rate in vitro, but play an important role in the pathogenesis of type 2 diabetes mellitus (T2DM). Here we report an easy and robust method to generate toxic hIAPP oligomers, which are stable for at least 8 hours. The toxic hIAPP oligomers are quickly transformed from α-helix to ß-sheet by membrane phospholipid, 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) liposomes, exhibiting distinct nanomechanical features from the hIAPP oligomers or pristine fibrils. DOPC liposomes significantly block the cytotoxicity induced by the hIAPP oligomers, which has the potential for new treatment.

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