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1.
Mediators Inflamm ; 2020: 2960517, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33013197

RESUMO

Insulin resistance has been shown to be the common pathogenesis of many metabolic diseases. Metainflammation is one of the important characteristics of insulin resistance. Macrophage polarization mediates the production and development of metainflammation. Toll-like receptor 4 (TLR4) mediates macrophage activity and is probably the intersection of immunity and metabolism, but the detailed mechanism is probably not fully understood. Activated protein 1 (AP1) signaling pathway is very important in macrophage activation-mediated inflammation. However, it is unclear whether AP1 signaling pathway mediates metabolic inflammation in the liver. We aimed to investigate the effects of macrophage TLR4-AP1 signaling pathway on hepatocyte metabolic inflammation, insulin sensitivity, and lipid deposition, as well as to explore the potential of TLR4-AP1 as new intervention targets of insulin resistance and liver steatosis. TLR4 and AP1 were silenced in the RAW264.7 cells by lentiviral siRNA transfection. In vivo transduction of lentivirus was administered in mice fed with high-fat diet. Insulin sensitivity and inflammation were evaluated in the treated cells or animals. Our results indicated that TLR4/AP-1 siRNA transfection alleviated high-fat diet-induced systemic and hepatic inflammation, obesity, and insulin resistance in mice. Additionally, TLR4/AP-1 siRNA transfection mitigated palmitic acid- (PA-) induced inflammation in RAW264.7 cells and metabolic abnormalities in cocultured AML hepatocytes. Herein, we propose that TLR4-AP1 signaling pathway activation plays a crucial role in high fat- or PA-induced metabolic inflammation and insulin resistance in hepatocytes. Intervention of the TLR4 expression regulates macrophage polarization and metabolic inflammation and further alleviates insulin resistance and lipid deposition in hepatocytes.

2.
Asian J Androl ; 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33037172

RESUMO

Accumulating evidence supports the significance of aberrant alternative splicing (AS) events in cancer; however, genome-wide profiling of progression-free survival (PFS)-related AS events in testicular germ cell tumors (TGCT) has not been reported. Here, we analyzed high-throughput RNA-sequencing data and percent-spliced-in values for 150 patients with TGCT. Using univariate and multivariate Cox regression analysis and a least absolute shrinkage and selection operator method, we identified the top 15 AS events most closely associated with disease progression. A risk-associated AS score (ASS) for the 15 AS events was calculated for each patient. ASS, pathological stage, and T stage were significantly associated with disease progression by univariate analysis, but only ASS and pathological stage remained significant by multivariate analysis. The ability of these variables to predict 5-year progression was assessed using receiver operating characteristic curve analysis. ASS had stronger predictive value than a combination of age, pathological stage, and T stage (area under the curve = 0.899 and 0.715, respectively). Furthermore, Kaplan-Meier analysis of patients with low and high ASS demonstrated that high ASS was associated with significantly worse PFS than low ASS (P = 1.46 × 10-7). We also analyzed the biological functions of the PFS-related AS-related genes and found enrichment in pathways associated with DNA repair and modification. Finally, we identified a regulatory network of splicing factors with expression levels that correlated significantly with AS events in TGCT. Collectively, this study identifies a novel method for risk stratification of patients and provides insight into the molecular events underlying TGCT.

3.
Chin J Integr Med ; 2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-33037518

RESUMO

OBJECTIVE: To evaluate whether the efficacy of Getong Tongluo Capsule (, GTC, consisted of total flavone of Radix Puerariae) on improving patients' quality of life and lowering blood pressure are superior to the extract of Ginkgo biloba (EGB) for patients with convalescent-phase ischemic stroke and primary hypertension. METHODS: This randomized, positive-drug- and placebo-controlled, double-blind trial was conducted from September 2015 to October 2017. Totally 477 eligible patients from 18 hospitals in China were randomly assigned in a 2:1:1 ratio to the following interventions, twice a day for 12 weeks: (1) GTC 250 mg plus EGB-matching placebo 40 mg (237 cases, GTC group), (2) EGB 40 mg plus GTC-matching placebo 250 mg (120 cases, EGB group) or (3) GTC-matching placebo 250 mg plus EGB-matching placebo 40 mg (120 cases, placebo group). Moreover, all patients were orally administered aspirin enteric-coated tablets 100 mg, once a day for 12 weeks. The primary outcome was the Barthel Index (BI). The secondary outcomes included the control rate of blood pressure and National Institutes of Health Stroke Scale (NIHSS) scores. The incidence and severity of adverse events (AEs) were calculated and assessed. RESULTS: The BI relative independence rates, the clinical recovery rates of NIHSS, and the total effective rates of NIHSS in the GTC and EGB groups were significantly higher than the placebo group at 12 weeks after treatment (P<0.05), and no statistical significance was found between the GTC and EGB groups (P>0.05). The control rate of blood pressure in the GTC group was significantly higher than the EGB and placebo groups at 12, 18 and 24 weeks after treatment (P<0.01). There were no statistically significant differences in the incidences of AEs, adverse drug reactions, or serious AEs among the 3 groups (P>0.05). CONCLUSION: GTC exhibited significant efficacy in improving patients' quality of life as well as neurological function and controlling hypertension. (Registration No. ChiCTR1800016667).

4.
Cancer Res ; 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-32998994

RESUMO

High-grade serous ovarian carcinoma (HGSOC) is the most lethal gynecologic malignancy in industrialized countries and has limited treatment options. Targeting ATR/CHK1-mediated S and G2/M cell cycle checkpoints has been a promising therapeutic strategy in HGSOC. To improve the efficacy of CHK1 inhibitors (CHK1i), we conducted a high-throughput drug combination screening in HGSOC cells. PI3K/mTOR pathway inhibitors (PI3K/mTORi) showed supra-additive cytotoxicity with CHK1i. Combined treatment with CHK1i and PI3K/mTORi significantly attenuated cell viability and increased DNA damage, chromosomal breaks and mitotic catastrophe compared to monotherapy. PI3K/mTORi decelerated fork speed by promoting new origin firing via increased CDC45, thus potentiating CHK1i-induced replication stress. PI3K/mTORi also augmented CHK1i-induced DNA damage by attenuating DNA homologous recombination repair activity and RAD51 foci formation. High expression of replication stress markers was associated with poor prognosis in patients with HGSOC. Our findings indicate that combined PI3K/mTORi and CHK1i induces greater cell death in HGSOC cells and in vivo models by causing lethal replication stress and DNA damage. This insight can be translated therapeutically by further developing combinations of PI3K and cell cycle pathway inhibitors in HGSOC.

5.
Theriogenology ; 158: 309-320, 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-33007716

RESUMO

Vitamin C (ascorbic acid, AA) can regulate antioxidation and affect many cellular processes. However, the effect of AA on the reproduction of male animals remains less explored. Here, we showed that by supplementing exogenous AA to porcine immature Sertoli cells (iSCs), AA could promote the proliferation, suppress apoptosis, and decrease the global nucleic acid methylation (5 mC and m6A) levels of iSCs. After we profiled mRNA and long non-coding RNA (lncRNA) expression by transcriptome sequencing on iSCs (treated by 250 µM AA for 36 h), 1232 mRNAs and 937 lncRNAs were identified to be differentially expressed (DE). Gene enrichment analysis found multiple significantly enriched biological pathways, including oxidoreductase activity, cell proliferation and apoptosis, regulation of hormone level, regulation of catalytic activity, developmental process, ATP metabolism and reproductive process. Specifically, for the reproductive process, 49 up- and 36 down-regulated DE mRNAs (including highly expressed genes, such as Tfcp2l1, Hmgcs1, Mmp7, Fndc3a, and Zfp36l1) are involved. Moreover, AA supplementation could promote the secretion of anti-müllerian hormone, inhibin B and lactate, and enhance the activity of lactate dehydrogenase as well. Taken together, AA could promote the reproductive function of pig iSCs, potentially through reprogramming the global transcriptome, and elevating hormone secretion and metabolite production.

6.
Medicine (Baltimore) ; 99(40): e21962, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33019388

RESUMO

To evaluate the association between gene polymorphisms of MTHFR (C677T, A1298C) and MTRR (A66G), and the recurrent spontaneous abortion (RSA) risk in Asia.Related case-control studies were collected, selected, and screened. A meta-analysis was conducted by Stata 12.0 software to assess the association between polymorphisms of target genes and RSA.Altogether 30 studies examining the relationship between genetic polymorphism of folate metabolism and RSA risk were included, among which 20 studies were related to MTHFR C677T, 11 to MTHFR A1298C and 6 to MTRR A66G. The studies suggested that MTHFR C677T polymorphism was closely connected with RSA risk under all models (P < .05). Furthermore according to the subgroup analysis of ethnicity, the correlation between C677T polymorphism and RSA was stronger in north of China when compared with south of China and other Asian countries (P > . 05). For MTHFR A1298C, it was closely related to RSA risk in all gene models except for (AC vs AA) (P < .05). However, when it comes to MTRR A66G, there was no significant correlation between gene A66G polymorphism and RSA risk except for the additive gene model (G vs A) (P < .05).The present evidence shows that the correlation between gene polymorphisms and RSA risk can be found in MTHFR C677T, A1298C (except for heterozygote model) and MTRR A66G (only in additive genotypes), and the detection of the correlated gene polymorphisms mentioned above is of certain guiding significance for preventing RSA and screening high-risk groups.

7.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 3003-3006, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018637

RESUMO

Exploring the brain response to stimuli of healthy people in passive state is helpful to understand the brain response mechanism of unresponsive people. Event-related potential (ERP) can reflect the time synchronization of potentials, which is a feasible objective electrophysiological index reflecting the functional status of the brain. In this paper, we used the subjects' own name (SON) as target stimuli and compared with the nontarget stimuli (others' name) of Three Chinese Characters (3CC) and Two Chinese Characters (2CC) with the same stimuli duration (600ms) and inter stimuli interval (500ms-800ms). Thirteen healthy subjects attended in this study with four conditions ( [active, passive]×[3CC, 2CC] ). We compared the ERP waveforms, the behavior performance, and the classification of four different conditions. ERP results show that the P300 amplitude of conditions with 3CC nontargets is higher than that of conditions with 2CC nontargets. Behavioral results show that the grand accuracy is 97% when the nontargets are 3CC, while the grand accuracy is only 94% when the nontargets are 2CC. The reaction time is also different from the two nontargets (605ms with 3CC vs 635ms with 2CC). Classification results illustrate that in active condition, the accuracy rate is 82.1% when the nontarget is 3CC, and that is 80.9% in passive condition, which are 4.2% and 6.4% higher than the accuracy rate under 2CC cases in both active and passive conditions. This study can provide a scheme for grading diagnosis of consciousness detection, and further applying to clinical evaluation.Clinical Relevance- This study can provide a better paradigm basis for clinical evaluation of unresponsive patients (such as disorder of consciousness, DOC) and may become an effective auxiliary means for clinical rating scales.

8.
J Colloid Interface Sci ; 583: 594-604, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-33039858

RESUMO

Herein, self-supported Ni3S2 spherical clusters packed with well-defined nanosheets developed on Ni foam (NF) were rationally fabricated via a novel low-temperature solvothermal sulfurization approach in a choline chloride/ethylene glycol (Ethaline)-based deep eutectic solvent (DES). The DES-based sulfurization process drove an interesting time-dependent surface restructuring and phase transformation that occurred on the Ni substrate, leading to the in-situ formation of a Ni3S2 layer with controllable architecture. Pre-deposition of a Ni interlayer on the NF substrate provides more assessable electrochemical surface area and reaction sites, which favored fast crystal nucleation/growth and structural reconstruction. Benefiting from the integrated design and unique 3D interdigital architecture, the optimized Ni3S2_5/Ni/NF with a sulfurization time of 5 h exhibits a high specific capacitance (specific capacity) of 5,633 mF cm-2 (860.6 µAh cm-2) at a current density of 10 mA cm-2, and maintains 87.7% of initial specific capacitance after 1,000 charge-discharge process at a current density of 20 mA cm-2. This facile DES-driven solvothermal sulfurization strategy for the fabrication of integrated metal sulfides-based electrode materials could be promising for practical applications in high-performance electrochemical devices.

9.
J Clin Lab Anal ; : e23623, 2020 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-33067885

RESUMO

BACKGROUND: Thromboelastography (TEG) provides global assessment of hemostatic function and has been recommended to monitor potential coagulopathies during pregnancy in which hypercoagulable state is favored. In present study, we established the reference intervals (RIs) of the TEG parameters (R, K, MA, and α-angle) with Chinese pregnant women of third trimester. In addition, we examined the diagnostic efficacies of the TEG parameters in the patients diagnosed of gestational hypertension (GH), gestational diabetes mellitus (GDM), or preeclampsia (PE). METHODS: With specified including and excluding criteria, non-pregnant controls, healthy pregnant women, and pregnant women with GH, GDM, or PE had their venous blood drawn at Beijing Obstetrics and Gynecology Hospital, followed by TEG tests performed in the clinical laboratory. RESULTS: The RIs determined with the healthy pregnant women (in third trimester) for R, K, MA, and α-angle were 4.0-7.7, 1.2-3.2, 51.9-70.1, and 41.4-74.4, respectively. When compared with the healthy pregnancy group, the K value was significantly decreased in GH patients but increased in PE patients; MA was significantly lower in the PE group. In the receiver operating characteristic curve (ROC) analyses, K value was able to efficiently distinguish normal pregnancy from the GH patients, with an AUC of 0.86 which is far better than those of R (AUC = 0.57) and MA (AUC = 0.56). For the PE patients, the AUC of MA (0.69) was significantly greater than that of R (0.50). CONCLUSIONS: Thromboelastography may provide more accurate experimental basis for monitoring coagulation functions especially in pregnant women with complications of GH and PE.

10.
Front Endocrinol (Lausanne) ; 11: 571037, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33071977

RESUMO

Background: Diabetes has been found to increase severity and mortality under the current pandemic of coronavirus disease of 2019 (COVID-19). Up to date, the clinical characteristics of diabetes patients with COVID-19 and the risk factors for poor clinical outcomes are not clearly understood. Methods: The study was retrospectively carried out on enrolled diabetes patients with laboratory confirmed COVID-19 infection from a designated medical center for COVID-19 from January 25th, 2020 to February 14th, 2020 in Wuhan, China. The medical record was collected and reviewed. Univariate and multivariate analyses were performed to assess the risk factors associated with the severe events which were defined as a composite endpoint of admission to intensive care unit, the use of mechanical ventilation, or death. Results: A total of 52 diabetes patients with COVID-19 were finally included in the study. 21 (40.4%) patients had developed severe events in 27.50 (IQR 12.25-35.75) days follow-up, 15 (28.8%) patients experienced life-threatening complications and 8 patients died with a recorded mortality rate of 15.4%. Only 13 patients (41.9%) were in optimal glycemic control with HbA1c value of <7.0%. In addition to general clinical characteristics of COVID-19, the severe events diabetes patients showed higher counts of white blood cells and neutrophil, lower lymphocytes (40, 76.9%), high levels of hs-CRP, erythrocyte sedimentation rate (ESR) and procalcitonin (PCT) as compared to the non-severe diabetes patients. Mild higher level of cardiac troponin I (cTNI) (32.0 pg/ml; IQR 16.80-55.00) and D-dimer (1.70 µg/L, IQR 0.70-2.40) were found in diabetes patients with severe events as compared to the non-severe patients (cTNI:20.00 pg/ml, IQR5.38-30.00, p = 0.019; D-dimer: 0.70 µg/L, IQR 0.30-2.40, p = 0.037). After adjusting age and sex, increased level of cTNI was found to significantly associate with the incidence of severe events (HR: 1.007; 95% CI: 1.000-1.013; p = 0.048), Furthermore, using of α-glucosidase inhibitors was found to be the potential protectant for severe events (HR: 0.227; 95% CI: 0.057-0.904; p = 0.035). Conclusion: Diabetes patients with COVID-19 showed poor clinical outcomes. Vigorous monitoring of cTNI should be recommended for the diabetes patients with COVID-19. Usage of α-glucosidase inhibitors could be a potential protectant for the diabetes patients with COVID-19.

11.
Artigo em Inglês | MEDLINE | ID: mdl-33074091

RESUMO

OBJECTIVE: Linezolid-induced thrombocytopenia is rarely reported in liver transplant patients, especially in children. CASE SUMMARY: We report a case of a 7-month-old liver-transplanted child who suffered from thrombocytopenia induced by linezolid. We simulated the pharmacokinetics of linezolid in a healthy adult using the physiologically based pharmacokinetic (PBPK) model and found that the liver is the most abundant organ for the distribution of linezolid. PRACTICE IMPLICATIONS: Linezolid has a high distribution in the liver. As a result, an increased awareness about the risk of linezolid-induced thrombocytopenia should be strengthened in patients with liver injury. Effects of ethnicity: The differences between Chinese patients and patients of other ethnicities may lead to the diverse effects of linezolid in different patients. The influence of body weight (BW) difference in pharmacokinetics (PK) of linezolid between Asian (Chinese and Japanese) and Caucasians was demonstrated in several population PK studies [1, 2, 3]. The average BW of Asians is lower than that of the Caucasian population, the clearance and apparent volume of distribution are lower than in the European population, and Cmax is higher than in the Western population. Therefore, the adverse effects of linezolid at the same dose may increase in Chinese patients.

12.
Neurobiol Aging ; 2020 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-32893041

RESUMO

TBK1 has been reported as a risk gene of amyotrophic lateral sclerosis (ALS). We screened TBK1 variants in 69 familial ALS patients and 608 sporadic ALS patients from mainland China. All 20 coding exons and the exon-intron flanking regions of TBK1 were amplified and sequenced using Sanger sequencing. In total, we identified eight missense variants and one suspicious splice site mutation. The patient with K291R had a family history of ALS. Other variants were detected in sALS patients. Interestingly, 2 patients with variants in TBK1 carried another variant in other genes related to autophagy: G175S in TBK1 and P392L in SQSTM1; and D534H in TBK1 and E372D in SQSTM1. We concluded that TBK1 variants account for approximately 1.3% of Chinese ALS patients. Screening for this gene in ALS patients is necessary, especially in the group with variants in other genes related to the autophagy pathway.

13.
Pharm Biol ; 58(1): 845-853, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32870741

RESUMO

CONTEXT: Cryptotanshinone (CT) is a diterpene quinone compound from Salvia miltiorrhiza Bge. Labiatae has been widely used in cardio-cerebral vascular diseases, which could be potentially effective in treating diabetic wounds. OBJECTIVE: This study evaluates the wound healing activity of CT by employing an excisional wound splinting model in db/db mice. MATERIALS AND METHODS: Wounds were induced at the dorsum of non-diabetic (db/+) and diabetic (db/db) mice and treated with sodium carboxymethyl cellulose (CMC-Na) or 300 mg/kg/d CT for 16 days. Wound closure was measured every two days. Body weight, fasting blood glucose, re-epithelialization, granulation, leukocyte infiltration, capillary density, collagen deposition and expressions of CXCL1, CXCL2, VEGF, Ang-1, p-eNOS, eNOS, α-SMA, MMP2 and MMP9 were analysed. Expression of VEGF and tube formation was measured in vitro with human umbilical vein endothelial cells (HUVECs). RESULTS: CT significantly accelerated rate of wound closure, as the contraction ratio increased from 68% (non-treated group) to 83% (CT-treated group) at days 16 post-injury. A significant increase was observed in re-epithelialization and granulation tissue formation. Mechanistically, CT suppressed leukocyte infiltration and CXCL1 and CXCL2 expression. CT treatment also increased blood vessel density and expression level of VEGF, Ang-1 and p-eNOS. In vitro, CT boosted expression of VEGF and tube formation of endothelial cells. Moreover, extracellular matrix (ECM) remodelling was enhanced by CT via promoting fibroblast transformation and inhibiting MMP2 and MMP9. CONCLUSIONS: Our study provides evidence that CT could be developed as a potential therapeutic agent for the treatment of chronic diabetic wound healing.

14.
Virol Sin ; 2020 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-32865701

RESUMO

Convalescent plasma therapy has been implemented in a few cases of severe coronavirus disease 2019. No report about convalescent plasma therapy in treating patients with prolonged positivity of SARS-CoV-2 RNA has been published. In this study, we conducted a retrospective observational study in 27 patients with prolonged positivity of SARS-CoV-2 RNA, the clinical benefit of convalescent plasma therapy were analyzed. qRT-PCR test of SARS-CoV-2 RNA turned negative (≤ 7 days) in a part of patients (early negative group, n = 15) after therapy, others (late negative group, n = 12) turned negative in more than 7 days. Pulmonary imaging improvement was confirmed in 7 patients in early negative group and 8 in late negative group after CP therapy. Viral load decreased in early negative group compared with late negative group at day 3, 5, 7 after implementing convalescent plasma therapy. Patients in early negative group had a shorter median length of hospital stay. In conclusion, convalescent plasma therapy might help eliminate virus and shorten length of hospital stay in patients with prolonged positivity of SARS-CoV-2 RNA.

15.
J Psychiatr Res ; 129: 281-288, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32882505

RESUMO

CLU encoding clusterin, has been reported to associate with Alzherimer's disease (AD) by genome-wide association studies (GWAS) based on Caucasian populations. Our previous case-control study has independently confirmed the disease association of CLU in Chinese population. Since little is known about the underlying mechanism of CLU in AD, we have conducted this study to investigate whether the genetic impact of CLU polymorphisms on cognitive functioning is via serum lipid's dysfunction. Three GWAS previously published CLU polymorphisms including rs2279590, rs11136000 and rs9331888, were genotyped in 689 subjects. Serum levels of triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) were measured and tested as mediators. Delayed Word Recall Test (DWRT) was used to evaluate subjects' memory performance. Multiple mediation analysis, a nonparametric procedure to create confidence interval, was performed according to Preacher and Hayes's Bootstrapping method. Our findings suggested significant correlation between CLU polymorphism and DWRT scores for rs11136000 (p = 0.045) after adjustment for age, gender, body mass index, and APOEε4 status, with borderline significant correlation for rs2279590 (p = 0.058). Both T allele of rs11136000 and A allele of rs2279590 were negatively correlated with serum TG levels (p = 0.003; p = 0.001, separately). Moreover, A allele of rs2279590 was positively correlated with serum HDL-C levels (p = 0.015). Consistent with our hypotheses, the genetic impact of CLU polymorphisms on memory performance were partially mediated through TG (rs11136000 95% CI [-0.099,-0.003] and rs2279590 95% CI [-0.104, -0.004]), but not through HDL-C and LDL-C. Our findings indicate CLU polymorphisms may modify AD susceptibility through lipid metabolic pathway.

16.
Mikrochim Acta ; 187(10): 564, 2020 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-32920653

RESUMO

A smartphone-based ratiometric fluorescence device was designed to monitor the reaction kinetic process under vigorous mixing conditions, demonstrated by the hydrolysis of Cs4PbBr6 nanocrystals (NCs). In the presence of trace water, part of Cs4PbBr6 NCs (non-fluorescent) was converted to CsPbBr3 NCs (strong fluorescent). Using anthracene as the reference fluorophore, the brightness ratio of the green (from CsPbBr3 NCs) to blue (from anthracene) components in the fluorescence image which was recorded in situ by the smartphone camera was measured as the signal for kinetic analysis. It was shown that the water-triggered conversion reaction from Cs4PbBr6 NCs to CsPbBr3 NCs follows the pseudo-second-order kinetic model in the early rapid hydrolysis stage (up to 4 min). With increasing water content, the hydrolysis of Cs4PbBr6 NCs is promoted to yield more CsPbBr3 NCs, which was used to determine trace water in n-hexane, dichloromethane, and toluene with detection limits of 0.031, 0.043, and 0.057 µL mL-1, respectively. The device offers the advantages of portability and low cost for rapid field determination of trace water in hydrophobic organic solvents. Graphical abstract.

17.
Artigo em Inglês | MEDLINE | ID: mdl-32929955

RESUMO

Cadmium sulfide (CdS) as one of the most common visible-light-responsive photocatalysts has been widely investigated for hydrogen generation. However, its low solar-hydrogen conversion efficiency caused by fast carrier recombination and poor catalytic activity hinders its practical applications. To address this issue, we develop a novel and highly efficient nickel-cobalt phosphide and phosphate cocatalyst-modified CdS (NiCoP/CdS/NiCoPi) photocatalyst for hydrogen evolution. The dual-cocatalysts were simultaneously deposited on CdS during one phosphating step by using sodium hypophosphate as the phosphorus source. After the loading of the dual-cocatalysts, the photocurrent of CdS significantly increased, while its electrical impedance and photoluminescence emission dramatically decreased, which indicates the enhancement of charge carrier separation. It was proposed that the NiCoP cocatalyst accepts electrons and promotes hydrogen evolution, while the NiCoPi cocatalyst donates electrons and accelerates the oxidation of sacrificial agents (e.g., lactic acid). Consequently, the visible-light-driven hydrogen evolution of this composite photocatalyst greatly improved. The dual-cocatalyst-modified CdS with a loading content of 5 mol % showed a high hydrogen evolution rate of 80.8 mmol·g-1·h-1, which was 202 times higher than that of bare CdS (0.4 mmol·g-1·h-1). This is the highest enhancement factor for metal phosphide-modified CdS photocatalysts. It also exhibited remarkable stability in a continuous photocatalytic test with a total reaction time of 24 h.

18.
Molecules ; 25(17)2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-32867051

RESUMO

Because of its tunable textural properties and chirality feature, chiral mesoporous silica (CMS) gained significant consideration in many fields and has been developed rapidly in recent years. In this review, we provide an overview of synthesis strategies for fabricating CMS together with its main applications. The properties of CMS, including morphology and mesostructures and enantiomer excess (ee), can be altered according to the synthetic conditions during the synthesis process. Despite its primary stage, CMS has attracted extensive attention in many fields. In particular, CMS nanoparticles are widely used for enantioselective resolution and adsorption of chiral compounds with desirable separation capability. Also, CMS acts as a promising candidate for the effective delivery of chiral or achiral drugs to produce a chiral-responsive manner. Moreover, CMS also plays an important role in chromatographic separations and asymmetric catalysis. There has been an in-depth review of the synthetic methods and mechanisms of CMS. And this review aims to give a deep insight into the synthesis and application of CMS, especially in recent years, and highlights the significance that it may have in the future.

19.
J Food Sci ; 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32990369

RESUMO

Cadmium (Cd) contamination in rice grain is common worldwide. This study investigated the effect of degree of milling (DM) on the reduction of Cd in cooked rice grain and porridge (rice-to-water ratios 1:1.6 and 1:10, respectively) and Cd in vitro bioaccessibility. Cd-contaminated rice grains with DMs of 20%, 15%, and 0% were cooked and then subjected to successive digestion in a gastrointestinal environment model. Simulated-digestion juices, including saliva, gastric juice, duodenal juice, and bile juice, were used. The degree of gelatinization of cooked rice was measured and the morphological characteristics of the grain were also examined. The results showed that the Cd in vitro bioaccessibility, although less than 50% in all samples, was gradually increased with an increase of DM. The detected Cd bioaccessibility was higher at half meals (reduced grain content) when compared with full meals (full grain content). As DM increased, the surface of cooked rice grain and porridge became smoother, and the amount of fiber, fat droplets, and starch granules were gradually decreased, whereas degree of gelatinization increased. The results indicate that DM affects the Cd in vitro bioaccessibility in cooked rice by altering the gelatinization of starch. PRACTICAL APPLICATION: Degree of milling (DM) significantly influenced the in vitro bioaccessibility of cadmium (Cd) in cooked rice. This work may offer a potential solution to the rice grain with high Cd content because a limited DM will allow a low bioaccessibility of Cd.

20.
J Org Chem ; 85(20): 13037-13049, 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-32909752

RESUMO

An environmentally sustainable strategy for the chemoselective heterocyclization of bromoenynes through a transition-metal-free sulfuration/cyclization process is reported. Using inexpensive and safe EtOCS2K as a thiol surrogate and tetrabutylphosphonium bromide and H2O as a mixed solvent, the reaction provided a range of substituted thiophenes in moderate to good yields. In addition, 2,3,4,5-tetrasubstituted thiophenes were able to be prepared under mild reaction conditions by electrophilic heterocyclization with NH4I and EtOCS2K in good yields.

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