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1.
Inorg Chem ; 2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-32163270

RESUMO

Because of the permission of the manipulations of modular construction on the atomic level, covalent organic frameworks (COFs) have attracted extensive attention in the electrocatalytic field. Owing to the lack of metal sites in pristine COFs constructed only by metal-free organic building units, it generally exhibits extremely low electrocatalytic activity. Thereby, linking metal sites on the backbone of pyrolysis-free COFs but not loading them on the surface to enhance the electrocatalytic activity is highly desirable but still remains a huge challenge. To this end, herein, we report an efficient and general cation-exchange strategy to synthesize Ni/Fe metal-ion-incorporated COFs (NixFe1-x@COF-SO3) for the oxygen evolution reaction (OER) based on the fundamental structure design of COFs. Impressively, the turnover frequency (TOF) value in Ni0.5Fe0.5@COF-SO3 reaches 0.14 s-1 at the overpotential of 300 mV, which outperforms most recently reported OER electrocatalysts, indicative of ultrahigh metal-atom utilization efficiency.

2.
Clin Transplant ; : e13856, 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32170765

RESUMO

Human leukocyte antigen (HLA)-haploidentical hematopoietic stem cell transplantation (haplo-HSCT) is an effective alternative to HLA-matched transplantation. However, Epstein-Barr virus (EBV) infection causes morbidity and mortality in patients undergoing haplo-HSCT. Here, we retrospectively evaluated the incidence and risk factors of EBV-DNAemia and EBV-associated diseases in 131 patients who underwent haplo-HSCT. Patients were classified into the no-EBV infection group, EBV-DNAemia group, and EBV-associated disease group. Cumulative incidences of acute graft-versus-host disease, EBV infections, overall survival (OS), and relapse were analyzed. The cumulative incidences of EBV-DNAemia and EBV-associated disease were 26.9% and 33.3%, respectively. In multivariate analysis, cytomegalovirus (CMV)-DNAemia was confirmed as an independent risk factor associated with EBV-DNAemia and EBV-associated disease. Patients with EBV-associated disease had higher transplant-related mortality (TRM) rates and lower OS rates, but similar relapse rates. Overall, these findings demonstrated the cumulative incidences of EBV-DNAemia and EBV-associated disease and identified correlations of EBV infection with TRM, relapse, and OS. Additionally, CMV-DNAemia was a risk factor for EBV-DNAemia and EBV-associated disease.

3.
Aging (Albany NY) ; 122020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32213661

RESUMO

It is crucial to grasp the characteristics of tumour immune microenvironment to improve effects of immunotherapy. In this study, the immune and stromal scores of 371 cases were calculated for quantitative analysis of immune and stromal cell infiltration in the tumour microenvironment of hepatocellular carcinoma (HCC). The weighted gene co-expression network analysis and protein-protein interaction network were analysed to identify immune microenvironment-related genes. The results showed that patients with high immune scores had a higher 4-year recurrence-free rate. TP53, CTNNB1, and AXIN1 mutations significantly varied with immune scores. In immune score-related modules analysis, Kyoto encyclopaedia of genes and genomes pathways and gene ontology terms were closely related to immune processes, tumorigenesis, and metastasis. Twelve new immune microenvironment-related genes were identified and had significantly positive correlations with seven immune checkpoint genes. In prognostic analysis, eleven immune microenvironment-related genes exhibited high expression, nine of which were validated in the GSE62232 dataset and were significantly associated with a good prognosis. Our findings suggest that calculating immune score and stromal score could help to determine tumour purity and immune cell infiltration in the tumour microenvironment. Nine immune microenvironment-related genes identified in this study had potential as prognostic markers for HCC.

4.
Biochem J ; 477(5): 887-903, 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32003433

RESUMO

So far, it has been still unknown how liamocins are biosynthesized, regulated, transported and secreted. In this study, a highly reducing polyketide synthase (HR-PKS), a mannitol-1-phosphate dehydrogenase (MPDH), a mannitol dehydrogenase (MtDH), an arabitol dehydrogenase (ArDH) and an esterase (Est1) were found to be closely related to core biosynthesis of extracellular liamocins in Aureobasidium melanogenum 6-1-2. The HR-PKS was responsible for biosynthesis of 3,5-dihydroxydecanoic acid. The MPDH and MtDH were implicated in mannitol biosynthesis and the ArDH was involved in arabitol biosynthesis. The Est1 catalyzed ester bond formation of them. A phosphopantetheine transferase (PPTase) activated the HR-PKS and a transcriptional activator Ga11 activated expression of the PKS1 gene. Therefore, deletion of the PKS1 gene, all the three genes encoding MPDH, MtDH and ArDH, the EST1, the gene responsible for PPTase and the gene for Ga11 made all the disruptants (Δpks13, Δpta13, Δest1, Δp12 and Δg11) totally lose the ability to produce any liamocins. A GLTP gene encoding a glycolipid transporter and a MDR1 gene encoding an ABC transporter took part in transport and secretion of the produced liamocins into medium. Removal of the GLTP gene and the MDR1 gene resulted in a Δgltp1 mutant and a Δmdr16 mutant, respectively, that lost the partial ability to secrete liamocins, but which cells were swollen and intracellular lipid accumulation was greatly enhanced. Hydrolysis of liamocins released 3,5-dihydroxydecanoic acid, mannitol, arabitol and acetic acid. We proposed a core biosynthesis pathway, regulation, transport and secretion of liamocins in A. melanogenum.

5.
Sci Rep ; 10(1): 3018, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32080225

RESUMO

The WRKY proteins are a superfamily of transcription factor that regulate diverse developmental and physiological processes in plants. Completion of the whole-genome sequencing of Aquilaria sinensis allowed us to perform a genome-wide investigation for WRKY proteins. Here, we predicted 70 WRKY genes from the A. sinensis genome and undertaken a comprehensive bioinformatic analysis. Due to their diverse structural features, the 70 AsWRKY genes are classified into three main groups (group I-III), with five subgroups (IIa-IIe) in group II, except two belong to none of them. Distinct expression profiles of AsWRKYs with RNA sequencing data revealed their diverse expression patterns among different tissues and in the process of whole-tree-inducing agarwood formation. Based on the expression characteristics, we predict some AsWRKYs are pseudogenes, and some may be involved in the biosynthesis of agarwood sesquiterpenes as activators or repressors. Among the tested genes treated with MeJA and H2O2, most of them are induced by H2O2, but downregulated by MeJA, implying the complexity of their involvement in signal transduction regulation. Our results not only provide a basic platform for functional identification of WRKYs in A. sinensis but important clues for further analysis their regulation role in agarwood formation.

6.
Can Respir J ; 2020: 1350872, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32104517

RESUMO

Introduction. Some studies have found that cilia were shorter in COPD smokers than in nonsmokers or healthy smokers. However, the structural abnormalities of cilia and the cause of such abnormalities in COPD patients still remain unknown. Tumor necrosis factor alpha receptor 3 interacting protein 1 (MIP-T3) may play an important role in the progress of ciliary protein transporting. Objectives: This study aimed at exploring the dominated structural abnormalities of cilia and the involvement of MIP-T3 in the pathogenesis of cilia of COPD patients. Methods: Patients who accepted pulmonary lobectomy were divided into 3 groups: the chronic obstructive pulmonary disease (COPD) smoker group, the healthy smoker group, and the nonsmoker group, according to smoking history and pulmonary function. The ultrastructure of cilia and the percentage of abnormal cilia were analyzed using a transmission electron microscope. Real-time PCR, immunohistochemical staining, and western blotting in bronchial epithelium were used to determine MIP-T3 mRNA and protein expression. The relationship between the percentage of abnormal cilia and lung function and MIP-T3 protein expression was analyzed. Results: Patients in the COPD smoker group had increased percentage of abnormal cilia comparing to both the healthy smoker group and the nonsmoker group (both P values <0.05). MIP-T3 expression was significantly declined in the COPD smoker group (P values <0.05). MIP-T3 expression was significantly declined in the COPD smoker group (P values <0.05). MIP-T3 expression was significantly declined in the COPD smoker group (P values <0.05). MIP-T3 expression was significantly declined in the COPD smoker group (. Conclusions: Our results suggested that the abnormal ciliary ultrastructure, which was common in COPD patients, might be due to MIP-T3 downregulation.

7.
Chin Med J (Engl) ; 133(3): 253-261, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31934936

RESUMO

BACKGROUND: Hepatitis C virus (HCV) genotype 3, particularly subtype 3b, is increasing in prevalence and distribution in China. This study evaluated the prevalence, regional distribution, clinical characteristics, host factors, treatment outcomes, and disease progression of patients with HCV genotype 3 in China. METHODS: A 5-year follow-up was preceded by a cross-sectional study. Treatment choices were at the discretion of treating physicians. Estimated infection time to overall-disease-progression (defined by ≥1 of: newly diagnosed cirrhosis; cirrhosis at baseline, Child-Turcotte-Pugh score increased 2 points or more; progression from compensated cirrhosis to decompensated cirrhosis; hepatocellular carcinoma; liver transplantation; or death) was calculated using the Kaplan-Meier method. Cox regression analyses were conducted to evaluate the risk factors for disease progression. RESULTS: The cross-sectional study enrolled 997 patients, including 91 with HCV genotype 3 infection. Among them, subtype 3b (57.1%) was more dominant than subtype 3a (38.5%). Five hundred and twelve patients were included into the follow-up phase. Among patients analyzed for estimated infection time to overall-disease-progression, 52/304 (17.1%) patients with HCV genotype 1 and 4/41 (9.8%) with HCV genotype 3 (4/26 with genotype 3b, 0/13 with genotype 3a, and 0/2 with undefined subtype of genotype 3) experienced overall-disease-progression. Patients with HCV genotype 3 were younger than those with genotype 1 (mean age: 39.5 ±â€Š8.7 vs. 46.9 ±â€Š13.6 years) and demonstrated more rapid disease progression (mean estimated infection time to overall-disease-progression 27.1 vs. 35.6 years). CONCLUSIONS: HCV genotype 3, specifically subtype 3b, is associated with more rapid progression of liver disease. Further analysis to compare HCV subtype 3a and 3b is needed in high prevalence regions. TRIAL REGISTRATION: NCT01293279, https://clinicaltrials.gov/ct2/show/NCT01293279; NCT01594554, https://clinicaltrials.gov/ct2/show/NCT01594554.

8.
BMC Cancer ; 20(1): 24, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31914946

RESUMO

BACKGROUND: The optimal chemotherapeutics of recurrent disseminated glioblastoma has yet to be determined. We analyzed the efficacy and safety of recombinant human endostatin (rh-ES) combined with temozolomide and irinotecan in patients with recurrent disseminated glioblastoma. METHODS: We retrospectively reviewed 30 adult patients with recurrent disseminated glioblastoma treated with this combination chemotherapy at Department of Neuro-Oncology, Sanbo Brain Hospital, Capital Medical University of China from November 2009 to August 2018. Temozolomide was given orally at 200 mg/m2 daily for 5 days and rh-ES was administrated 15 mg/d daily for 14 days of each 28-day treatment cycle. Irinotecan was given intravenously every 2 weeks on a 28-day cycle at 340 mg/m2 or 125 mg/m2 depending on antiepileptic drugs. Primary endpoint was progression-free survival (PFS) at 6 months (6 m-PFS). RESULTS: The 6 m-PFS was 23.3%. The median PFS was 3.2 months. The overall survival rate (OS) at 12 months was 28.6%. The median OS was 6.9 months. Six out of 30 (20%) patients demonstrated partial radiographic response and 11 (36.7%) remained stable. The PFS of the 6 patients who got partial response was 5.8, 6.3, 6.9, 13.6, 15.8 and 16.6 months, respectively, and the median time interval of first response was 4 (range, 2.0-6.6) months. The most common adverse events were hematologic toxicities and gastrointestinal effects. The Grade ≥ 3 adverse event was hematologic toxicities. The adverse events were manageable. CONCLUSIONS: Rh-ES, in combination with cytotoxic drugs, was an alternative effective regimen with manageable toxicities in treatment of recurrent disseminated glioblastoma.

9.
Psychogeriatrics ; 2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31976614

RESUMO

Even after successful hip arthroplasty, elderly patients who have undergone this procedure remain subject to cognitive decline and may collectively develop postoperative cognitive dysfunction (POCD). However, no consensus exists as to the risk factors resulting in a higher likelihood that a patient may present with this complication, and the aetiology of POCD is not well understood. We conducted a systematic review of papers concerning the influence of POCD-related risk factors in patients undergoing hip arthroplasty but limited the literature search to papers in English. A systematic and electronic search for manuscripts in the PubMed database was performed in order to identify all studies in which the risk factors for POCD were investigated. Articles were also obtained from the authors' files. Keywords for the search were postoperative cognitive dysfunction/change/impairment/decline/deficit, elderly/older/aged patients, and hip arthroplasty/replacement surgery. The evidence published to date suggests that POCD is a multifactorial disease, which includes an individual patient's characteristics, surgery, type of anaesthesia, and pain levels. All of these factors can increase the risk of POCD incidence. There are a number of factors that appear to influence the risk of early cognitive dysfunction after hip arthroplasty. Nevertheless, the specific mechanism and explicit risk factors associated with this cognitive dysfunction are not completely understood. Hip arthroplasty has made it possible for older patients to find relief from pain and improve their function, whereas it also increases the risk for suffering POCD that may affect these patients' quality of life and increase their mortality. Therefore, it is worthwhile investigating the mechanism of POCD in future studies in order to prevent and treat this condition.

10.
Obes Surg ; 30(1): 279-289, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31605365

RESUMO

BACKGROUND: Duodenal-jejunal bypass (DJB) can dramatically improve type 2 diabetes independent of weight loss and food restriction. Increasing evidence has demonstrated that brain insulin signaling plays an important role in the pathophysiology of type 2 diabetes. This study explores whether the antidiabetic effect of DJB is involved in brain insulin signaling activation and brain glucose utilization. METHODS: A diabetic rat model was established by high-fat and high-glucose diet. DJB or sham surgery was performed in diabetic rats. 18F-FDG PET scanning was used to detect glucose uptake in different organs, particularly in the brain. The levels of glucose transporters, glucose utilization-related proteins (HK1 and PFK2), insulin, and insulin signaling pathway-related proteins (InsR, IRS1/2, PI3K, and p-Akt) in the brain tissues were evaluated and analyzed. RESULTS: The results showed that DJB significantly improved basal glycemic parameters and reversed the decreasing glucose uptake in the brains of type 2 diabetic rats. DJB significantly increased not only the expression levels of brain insulin, IRS1/2, PI3K, and p-Akt but also the levels of the glucose utilization enzymes HK1 and PFK2 in the brain. CONCLUSION: These results indicate that enhanced brain insulin signaling transduction and brain glucose utilization play important roles in the antidiabetic effect of DJB.

11.
World Neurosurg ; 133: e165-e172, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31476465

RESUMO

BACKGROUND: Cartilaginous endplate (CEP), a thin layer of hyaline cartilage located between the vertebral endplate and nucleus pulposus, transports the nutrient into the disc. The objective of this study was to evaluate the influence of T140 (polyphemusin II-derived peptide) on the CEP cell growth, apoptosis, and the matrix formation via the stromal cell-derived factor-1 (SDF-1)/cysteine X cysteine (CXC) receptor-4 (CXCR4) signaling pathway. METHODS: Sprague-Dawley rats were euthanized by cervical dislocation and dissected for the isolation and the appraisal of CEP cells that were extracted from the endplate in rat intervertebral discs and were then added with different concentrations of reagents (SDF-1 and T140). The effect of T140 on CEP cell proliferation and apoptosis were analyzed. The messenger RNA (mRNA) and protein expressions of CXCR4, prominin-1, proteoglycans, type II collagen, B-cell lymphoma-2 (Bcl-2), and Bcl-2 associated X protein were analyzed by reverse transcription quantitative polymerase chain reaction and Western blot analysis. RESULTS: T140 promoted the proliferation of CEP cells and inhibited the apoptosis of CEP cells. Additionally, T140 suppressed the mRNA and protein expression of CXCR4, prominin-1, and Bcl-2 associated X protein, and increased the mRNA and protein expression of proteoglycans, type II collagen, and Bcl-2. CONCLUSIONS: T140 promotes the proliferation and matrix formation and inhibits the apoptosis of CEP cells by blocking the SDF-1/CXCR4 signaling pathway in vitro, which provides a certain therapeutic effect on the degeneration of intervertebral discs.


Assuntos
Apoptose/efeitos dos fármacos , Quimiocina CXCL12/fisiologia , Condrócitos/efeitos dos fármacos , Matriz Extracelular/efeitos dos fármacos , Cartilagem Hialina/citologia , Disco Intervertebral/citologia , Oligopeptídeos/farmacologia , Receptores CXCR4/fisiologia , Transdução de Sinais/efeitos dos fármacos , Animais , Divisão Celular/efeitos dos fármacos , Proteínas da Matriz Extracelular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Disco Intervertebral/efeitos dos fármacos , Masculino , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley
12.
J Exp Bot ; 71(3): 1128-1138, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31639819

RESUMO

Agarwood is derived from wounds in Aquilaria trees and is widely used in traditional medicine, incense, and perfume. Sesquiterpenes are one of the main active components in agarwood and are known to be induced by wounding or injury; However, the molecular mechanisms by which wounding leads to sesquiterpene formation remain largely unknown. Agarwood sesquiterpene synthase 1 (ASS1) is one of key enzymes responsible for the biosynthesis of sesquiterpenes and is a crucial jasmonate (JA)-responsive wound-inducible synthase. However, it is not known why ASS1 is not expressed in healthy trees and how its expression is induced as a result of wounding. Here, we report that ASS1 is a wound-induced gene with a promoter in which a 242-bp region (-973 to -731bp) is identified as the core sequence for responding to wound signals. AsWRKY44 binds directly to this region and represses ASS1 promoter activity. Down-regulation or disruption of AsWRKY44 can relieve the inhibition and activate ASS1 expression. In addition, AsWRKY44 is degraded and the expression of ASS1 is significantly up-regulated in response to exogenous application of methyl jasmonate. Thus, AsWRKY44 is a crucial negative regulator of wound-induced ASS1 transcription, and is central to the mechanism of sesquiterpene biosynthesis in agarwood.

13.
J Cell Physiol ; 235(2): 1339-1348, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31256441

RESUMO

This study aimed to investigate the molecular mechanisms underlying the roles of metformin (MET) and Sorafenib (SOR) in the treatment of endometrial hyperplasia (EH) in polycystic ovary syndrome (PCOS). Effects of MET and SOR on the area of endometrium and myometrium were detected. Western blot analysis and immunohistochemistry assays were carried out to detect the levels of mammalian target of rapamycin complex 1 (mTORC1), mTORC2, LC3-II, P62, and Caspase-3 in rats and cultured cells. Furthermore, cell counting kit-8 assay and flow cytometry analysis was carried out to determine the apoptotic profiles of treated cells. MET and SOR could apparently decrease the areas of endometrium and myometrium in PCOS. MET notably enhanced the expression of LC3-II and Caspase-3 in PCOS while substantially reducing the level of mTORC1 and P62. Similarly, SOR also enhanced the expression of LC3-II and Caspase-3 in PCOS while substantially reducing the level of mTORC2 and P62. Treatment with MET and SOR significantly inhibited the proliferation of HCC-94 and HEC-1-A cells while promoting their apoptosis by upregulating the expression of Caspase-3. In cells treated with MET, the expression of mTORC1 and LC3-II was upregulated while the expression of P62 was downregulated. Similarly, in cells treated with SOR, the expression of mTORC2 and LC3-II was also upregulated while the expression of P62 was also downregulated. Furthermore, MET showed no effect on mTORC2 expression, while SOR showed no effect on mTORC1 expression. In this study, we suggested that MET and SOR alleviated the risk of EH in PCOS via the mTORC1/autophagy/apoptosis axis and mTORC2/autophagy/apoptosis axis, respectively.

14.
Anal Chim Acta ; 1094: 151-159, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31761042

RESUMO

Based on superparamagnetic nanoparticles, a responsive polyacrylamide hydrogel self-assembled by nucleic acid hairpin hybridization chain reaction was designed, and a universal low field nuclear magnetic resonance sensing platform was successfully constructed. As the target was gradually added, the hydrogel coating on the surface of the magnetic nanoparticle was opened layer by layer through binding with the aptamer, which specifically bonded thereto, causing different degrees of exposure of the magnetic nanoparticle, resulting in changes of low field nuclear magnetic resonance signals. This method was originally applied to the rapid detection of adenosine triphosphate (ATP), and the versatility of the method was verified using polychlorinated biphenyl 77 (PCB77). This method had the advantage of being fast, convenient, and low cost, and it can be easily operated with high repeatability. This universal method can detect a variety of targets by replacing aptamers and may be useful in controlling food quality and for rapidly detecting cancer cells in vitro.


Assuntos
Resinas Acrílicas/química , Trifosfato de Adenosina/sangue , Hidrogéis/química , Nanopartículas de Magnetita/química , Bifenilos Policlorados/análise , Animais , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/genética , Sequência de Bases , Técnicas Biossensoriais/métodos , Bovinos , DNA/química , DNA/genética , Água Potável/análise , Sequências Repetidas Invertidas , Limite de Detecção , Espectroscopia de Ressonância Magnética/métodos , Hibridização de Ácido Nucleico , Poluentes Químicos da Água/análise
15.
Int J Nanomedicine ; 14: 9437-9452, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31819442

RESUMO

Background: The tumor-targeting ability and pH-sensitive properties of intelligent drug delivery systems are crucial for effective drug delivery and anti-tumor therapy. Methods: In this study, sHA-DOX/HA-GA mixed micelles were designed with the following properties: sulfated hyaluronic acid (sHA) was synthesized to block cell migration by inhibiting HAase; sHA-DOX conjugates were synthesized via pH-sensitive hydrazone bond to realize DOX-sensitive release. The introduction of HA-GA conjugate could improve active-targeting ability and cellular uptake. Results: The results showed that the mixed micelles possessed a nearly spherical shape, nanoscale particle size (217.70±0.89 nm), narrow size distribution (PDI=0.07±0.04), negative zeta potential (-31.87±0.61 mV) and pH-dependent DOX release. In addition, the sHA-DOX/HA-GA micelles exhibited concentration-dependent cytotoxicities against liver carcinoma cells (HepG2) and HeLa cells, and were shown to be effectively taken up by HepG2 cells by confocal microscopy analysis. Furthermore, the in vivo anti-tumor study showed that mixed micelles had a superior anti-tumor effect compared to that of free DOX. Further evidence obtained from the hematoxylin-eosin staining and immunohistochemistry analysis also demonstrated that sHA-DOX/HA-GA exhibited stronger tumor inhibition and lower systemic toxicity than free DOX. Conclusion: The sHA-DOX/HA-GA mixed micelles could be a potential drug delivery system for anti-hepatoma therapy.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Ácido Hialurônico/química , Neoplasias Hepáticas/tratamento farmacológico , Fígado/patologia , Micelas , Sulfatos/química , Carcinoma Hepatocelular/patologia , Movimento Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Liberação Controlada de Fármacos , Endocitose , Células HeLa , Células Hep G2 , Humanos , Concentração de Íons de Hidrogênio , Fígado/efeitos dos fármacos , Neoplasias Hepáticas/patologia , Tamanho da Partícula , Polímeros/química , Distribuição Tecidual/efeitos dos fármacos
16.
Dis Markers ; 2019: 2585409, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31885733

RESUMO

Background and Aim: Little information is available about the assessment and optimal use of the gamma-glutamyl transpeptidase-to-platelet ratio (GPR) and transient elastography (TE) in predicting liver cirrhosis in patients with chronic hepatitis B (CHB) and concurrent nonalcoholic fatty liver disease (NAFLD). This study is aimed at comparing their diagnostic performances and developing an optimal approach for predicting liver cirrhosis in CHB patients with NAFLD. Methods: Consecutive CHB patients with NAFLD were enrolled. The GPR was calculated, and TE was performed using liver biopsy as a reference standard. The accuracy of predicting liver cirrhosis using GPR and TE was assessed and compared, and an optimal approach was developed. Results: Both TE and GPR correlated significantly with the histological fibrosis stage. TE and GPR had excellent performance in predicting liver cirrhosis, and the comparison of areas under the receiver operating characteristic curves revealed that TE was superior to GPR (0.95 vs. 0.85, P = 0.039). Moreover, the dual cutoffs established by the likelihood ratio showed that GPR had a similar misclassification but higher indeterminate rate than TE (54.5% vs. 11.7%, P < 0.001). Additionally, a 2-step approach using GPR followed by TE had comparable performance to that of both GPR and TE tests for all patients (misclassification: 8.9% vs. 8.3%, P = 0.866; indeterminate rate: 15.2% vs. 17.2%, P = 0.750) but could reduce TE scans by approximately one-third. Conclusions: Both TE and GPR show excellent performance in predicting liver cirrhosis in CHB patients with NAFLD. The 2-step approach using GPR followed by TE may be optimal for the assessment of cirrhosis in CHB patients with NAFLD.

17.
Huan Jing Ke Xue ; 40(9): 4253-4261, 2019 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854892

RESUMO

A field trial was conducted with abandoned Pb-Zn mine tailings to evaluate the effectiveness of amendments with different C/N/P ratios on plant growth, soil nutrients and enzyme activities, and heavy metal concentrations in plant tissues and the mine tailings. The following results were noted. ①The application of amendments with different C/N/P ratios promoted plant growth and development. The vegetation cover and biomass increased from 2.0%-20.0% and 9.4-115 g·m-2 at 6 months to 62.5%-98.5% and 389-2358.3 g·m-2 at 30 months, respectively. ②When compared with the control tailings, the mean values of organic carbon, water organic carbon, nitrate nitrogen, and available phosphorus in the treatments with different C/N/P ratios increased 6.0%-93.3%, 1.3%-49.3%, 12.3%-214.7%, and 2.7%-81.3%, respectively. Similarly, the addition of amendments with different C/N/P ratios enhanced the soil enzyme activities of dehydrogenase, ß-glucosidase, urease, and phosphatase 0.3-2.8, 0.1-1.4, 0.1-0.6, and 0.1-0.5 times those in the tailings. ③The addition of amendments with different C/N/P ratios decreased the concentrations of diethylenetriamine pentaacetate (DTPA)-extracted Cd, Cu, Pb, and Zn in the mine tailings and the accumulation of Cd, Cu, Pb, and Zn in plant tissues in different degrees. DTPA-Cd, DTPA-Cu, DTPA-Pb, and DTPA-Zn decreased 2.5%-40.2%, 1.4%-25.6%, 1.4%-15.2%, and 0.4%-24.9%, respectively, compared with the control tailings. ④Pearson's correlation coefficients showed that the vegetation cover and biomass were correlated positively with the soil nutrient elements and enzyme activities and negatively with DTPA-extractable metal concentrations. No correlations were observed between the plant metal concentrations and soil DTPA-extractable metal concentrations, nutrient elements, and enzyme activities. Generally, amendments with different C/N/P ratios aided phytostabilization of some types of mine tailings is the preferred option for full remediation of these mine wastelands.


Assuntos
Metais Pesados , Mineração , Poluentes do Solo , Chumbo , Plantas , Solo , Zinco
18.
Plant J ; 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31713923

RESUMO

The centromere, as an essential element to mediate chromosome segregation, is epigenetically determined by CENH3-containing nucleosomes as a functional marker; therefore the accurate deposition of CENH3 is crucial for chromosome transmission. We characterized the deposition of CENH3 in maize by over-expression and mutational analysis. Our results revealed that over-expressing CENH3 in callus is lethal while over-expressing GFP-CENH3 and CENH3-YFP in callus and plants is not and can be partly deposited normally. Different mutations of GFP-CENH3 demonstrated that CENH3-Thr4 in the N-terminus was needed for the deposition as a positive phosphorylation site and the last five amino acids in the C-terminus are necessary for deposition. The C-terminal tail of CENH3 is confirmed to be responsible for the interaction of CENH3 and histone H4, which indicates that CENH3 maintains deposition in centromeres via interacting with H4 to form stable nucleosomes. For GFP-CENH3 and CENH3-YFP, the fused tags at the termini probably affect the structure of CENH3 and reduce its interaction with other proteins, which in turn could decrease proper deposition. Taken together, multiple amino acids or motifs were shown to play essential roles in CENH3 deposition, which is suggested to be affected by numerous factors in maize.

19.
Plants (Basel) ; 8(11)2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31731732

RESUMO

The incidence of short episodes of high temperature in the most productive rice growing region is a severe threat for sustainable rice production. Screening for heat tolerance and breeding to increase the heat tolerance of rice is major objective in the situation of recent climate change. Replacing sensitive genotypes with heat tolerant cultivars, modification in sowing time, and use of growth regulators are some of the adaptive strategies for the mitigation of yield reduction by climate change. Different strategies could be adopted to enhance the thermos-tolerance of rice by (1) the modification of agronomic practices i.e., adjusting sowing time or selecting early morning flowering cultivars; (2) induction of acclimation by using growth regulators and fertilizers; (3) selecting the genetically heat resistant cultivars by breeding; and, (4) developing genetic modification. Understanding the differences among the genotypes could be exploited for the identification of traits that are responsible for thermo-tolerance for breeding purpose. The selection of cultivars that flowers in early morning before the increase of temperature, and having larger anthers with long basal pore, higher basal dehiscence, and pollen viability could induce higher thermo-tolerance. Furthermore, the high expression of heat shock proteins could impart thermo-tolerance by protecting structural proteins and enzymes. Thus, these traits could be considered for breeding programs to develop resistant cultivars under a changing climate.

20.
Chem Commun (Camb) ; 55(97): 14625-14628, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31746855

RESUMO

Au nanoparticles were asymmetrically fabricated at one tip of TiO2 nanochannels by combining a photocatalytic reaction and limited penetration of light. Using the asymmetrical nanochannel-based membrane as a plasma absorber, near-infrared-gated artificial ionic nanochannels were designed.

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