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1.
Eur Radiol ; 30(1): 461-470, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31297632

RESUMO

PURPOSE: To assess the diagnostic performance of the LR-M criteria of Contrast-Enhanced Ultrasound Liver Imaging Reporting and Data System version 2017 in differentiating intrahepatic cholangiocarcinoma (ICC) from hepatocellular carcinoma (HCC) in patients with and without risk factors for HCC. METHODS: Fifty-four ICC in patients with risks and 55 ICC in patients without risks and matched control cases of HCC with and without risks (n = 59 and n = 55, respectively) were enrolled. The enhanced features of the lesions were retrospectively analyzed according to LR-M criteria. The diagnostic performances including the area under the receiver operating characteristic curve (AUC), sensitivity, and specificity of LR-M criteria were assessed. RESULT: Peripheral rim-like hyperenhancement, early washout (< 45 or 60s), and marked washout did not differ between ICCs with and without risks, while all of these features were more common in ICCs than in HCCs (p < 0.05) no matter if patients were with and without risk factors. Using the LR-M criteria to differentiate ICC from HCC, the AUC, sensitivity, specificity, and accuracy were 0.92, 97.25%, 87.72%, and 92.38%, respectively. If early washout onset was adjusted to < 45 s, the specificity was significantly increased to 95.61% (p = 0.004) without losing sensitivity (96.33%, p = 0.945). The rate of HCCs misdiagnosed as ICCs would decrease from 12.3 to 4.4%. CONCLUSION: Although the LR-M criteria showed high sensitivity in distinguishing ICCs from HCCs in patients with and without risks, the specificity would be significantly increased after adjustments to current criteria. KEY POINTS: • The LR-M criteria of CEUS-LI-RADS v2017 could be used for distinguishing ICC from HCC not only in patients with risk factors for HCC but also in those without risk factors. • The diagnostic performance of differentiating ICC from HCC by using the LR-M criteria showed high AUC (0.92), high sensitivity (97.25%), intermediate specificity (87.72%), and high accuracy (92.38%). • If the onset of early washout was adjusted to < 45 s, the specificity was significantly increased from 87.72 to 95.61% (p = 0.004) without losing sensitivity (p = 0.945), and the rate of HCCs misdiagnosed as ICCs would decrease from 12.3 to 4.4%.

2.
J Pharm Biomed Anal ; 177: 112808, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31585328

RESUMO

Consulting the national pharmacopoeia, no official quality standard was found for estimation of related substances and assay of atosiban acetate injection, of which main active component is atosiban. To solve this problem, herein, a novel high performance liquid chromatographic (HPLC) method was developed and validated in this study. A chromatographic system comprising an Inertsil ODS-2 analytical column, mobile phase-A of water (pH adjusted to 3.2 with trifluoroacetic acid)-acetonitrile-methanol (77:14:9, v/v/v), mobile phase-B of acetonitrile-methanol (65:35, v/v), a flow rate of 1.0 mL min-1 and a UV detector set at 220 nm with column temperature at 35 °C has shown simple, reproducible and specific determination for atosiban and its five related substances. Also, we combined with mass spectrometry to characterize the molecular weight and tentative structure of the impurities. Using HPLC verified methodology, results of the validation study showed that the precision, specificity and accuracy of the five impurities, good linear equation R squared was greater than 0.9993, and as such, the limit of detection and the limit of quantification have been determined. The proposed method in this study, which, to the best of our knowledge, is the most comprehensive HPLC determination applied to the routine analysis in quality control of this injection.

3.
Biomed Pharmacother ; 121: 109596, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31731193

RESUMO

Vasoactive intestinal peptide (VIP) is a neuropeptide that exerts anti-inflammatory functions. We have reported that VIP mediated by lentivirus attenuates acute lung injury (ALI) in lipopolysaccharide (LPS)-induced murine model. However, the exact role of VIP in uncontrolled inflammation during ALI is largely unknown. Accumulating evidence indicates that the NLRP3 inflammasome has a critical role during ALI. In this study, we investigated the effects of VIP on the activation of NLRP3 inflammasome during the development of ALI in mice. Seven days after the intratracheal injection of VIP-lentivirus, a murine ALI model was induced by intratracheal injection of LPS. VIP-lentivirus significantly reduced the expression of NLRP3 inflammasome components in lung tissue, including NLRP3, pro-caspase-1, pro-IL-1ß, and pro-IL-18. VIP-lentivirus also inhibited the formation of caspase-1 p10 and the maturation of IL-1ß and IL-18. In vitro, exogenous VIP pre-treatment inhibited the priming of NLRP3 inflammasome in murine primary peritoneal macrophages, indicated by down-regulation of expression of NLRP3 inflammasome components. VIP pre-treatment effectively prevented the LPS-induced degradation of I-κB and the synthesis of the downstream of NF-κB, including TNF-α and IL-17A. Furthermore, VIP pre-treatment pronouncedly suppressed the autoproteolysis of caspase-1 and the secretion of IL-1ß and IL-18 induced by LPS plus ATP in macrophages. In addition, VIP inhibited the generation of reactive oxygen species in macrophages by decreasing NOX1 and NOX2 expression. These findings illustrate one mechanism that VIP attenuates ALI induced by LPS through inhibiting the activation of the NLRP3 inflammasome and encourage further studies assessing the therapeutic potential of VIP to ALI.

4.
Food Microbiol ; 86: 103343, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31703887

RESUMO

The bacterial conversion of glutamine to glutamate is catalyzed by glutamine-amidotransferases or glutaminases. Glutamine deamination contributes to the formation of the bioactive metabolites glutamate, γ-aminobutyrate (GABA) and γ-glutamyl peptides, and to acid resistance. This study aimed to investigate the distribution of glutaminase(s) in lactobacilli, and to evaluate their contribution in L. reuteri to amino acid metabolism and acid resistance. Phylogenetic analysis of the glutaminases gls1, gls2 and gls3 in the genus Lactobacillus demonstrated that glutaminase is exclusively present in host-adapted species of lactobacilli. The disruption gls1, gls2 and gls3 in L. reuteri 100-23 had only a limited effect on the conversion of glutamine to glutamate, GABA, or γ-glutamyl peptides in sourdough. The disruption of all glutaminases in L. reuteri 100-23Δgls1Δgls2Δgls3 but not disruption of gls2 and gls3 eliminated the protective effect of glutamine on the survival of the strain at pH 2.5. Glutamine also enhanced acid resistance of L. reuteri 100-23ΔgadB and L. taiwanensis 107q, strains without glutamate decarboxylase activity. Taken together, the study demonstrates that glutaminases of lactobacilli do not contribute substantially to glutamine metabolism but enhance acid resistance. Their exclusive presence in host-adapted lactobacilli provides an additional link between the adaptation of lactobacilli to specific habitats and their functionality when used as probiotics and starter cultures.

5.
Food Chem ; 303: 125394, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31473455

RESUMO

A simple and effective vesicle based ultrasonic-assisted extraction (UAE) method was developed for extraction of active compounds in functional food. The target analytes were determined by ultra-high performance liquid chromatography with ultraviolet detector. Surfactant vesicle was adopted as extraction solvent. Different operating conditions including the type and concentration of vesicle, extraction time and solid to liquid ratio were investigated by single-factor experiments and response surface methodology. Optimized experimental conditions were 1% (w/v) of DTAB/SDS vesicle, 20 min of extraction time and 160 mg/mL of solid to liquid ratio. The proposed method provided good linearity in the linear range of 10-1000 µg/mL with regression coefficients larger than 0.999, low limits of detection of 27.64-55.67 ng/mL, good precision with relative standard deviations below 0.35%, and satisfactory recoveries of 83.84-90.92% for tested saponins. Consequently, the proposed vesicle based UAE method was well suited for the extraction of saponins in Panax notoginseng.


Assuntos
Fracionamento Químico/métodos , Panax notoginseng/química , Saponinas/isolamento & purificação , Ultrassom , Cromatografia Líquida de Alta Pressão , Saponinas/análise
6.
Chemosphere ; 238: 124586, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31442775

RESUMO

Cyantraniliprole can effectively control lepidopteran pests and has been used all over the world. In general, the risk of cyantraniliprole seems low for fish, but the toxicity selectivity among different fish species was not clear. Here the acute toxicity and chronic effects of cyantraniliprole to juvenile tilapia (Oreochromis mossambicus) were assessed. The results showed that 96 h LC50 of cyantraniliprole to tilapia was 38.0 mg/L. After exposed for 28 days, specific growth rates of the blank control, solution control, and the treatments of 0.037, 0.37 and 3.7 mg/L of cyantraniliprole were 1.14, 0.95, 0.93, 0.82 and 0.70% per day, respectively. The results of micronucleus experiment and single cell gel electrophoresis showed that cyantraniliprole damaged DNA in liver cells of tilapia larvae. Quantitative PCR results showed that cyantraniliprole could induce the up-regulation of Rpa 3 that is responsible for the DNA repair. The significantly down-regulation of Chk 2 gene was related to p53 pathway. It is therefore proposed that cyantraniliprole causes DNA damage in liver cells of tilapia and activates DNA damage and repair pathways.

7.
Chemosphere ; 238: 124620, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31472354

RESUMO

Particulate toxic species, such as polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs), polycyclic aromatic hydrocarbons (PAHs) and heavy metals may have significant health risks. This study investigated characteristics, sources and health risks of all three classes of toxic species in PM2.5 (particles with aerodynamic diameter ≤2.5 µm) samples collected at an industrial area in Changzhou, a big city in the Yangtze Delta region of China. Fourteen heavy metals altogether constituted 2.87% of PM2.5 mass, with Fe, Al and Zn as the major elements. Principal component analysis (PCA) suggested that heavy metals came from four sources: vehicles, industry, crustal dust, mixed coal combustion and industrial process. The daily average concentration of 18 PAHs was 235.29 ng/m3, accounting for 0.21% of PM2.5 mass. The dominant PAHs were high molecular weight ones, contributing 73.5% to the total PAHs. Diagnostic analyses indicated that sources of PAHs included vehicle/coal combustion and petroleum emissions, wherein diesel emission played a more important role than gasoline emission. PCA showed that the largest contributor of PAHs was vehicle exhaust mixed with coal combustion, followed by three industry-related sources. Total concentration of 17 PCDD/Fs varied between 3.14 and 37.07 pg/m3, with an average of 14.58 pg/m3. The 10 PCDFs accounted for 70.5% of total concentration of 17 PCDD/Fs. Health risk assessments showed that the carcinogenic risk of heavy metals was acceptable, while risks from PAHs and PCDD/Fs cannot be ignored. Back trajectory analysis indicated that local/regional transported air masses from northern China was the major source areas of the toxic species.

8.
Talanta ; 207: 120259, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31594574

RESUMO

We report a new method: biomimetic cell-cell adhesion capillary electrophoresis (BCCACE) to screen drugs targeting interactions between cell membrane receptors and ligands under an environment close to physiological conditions, in which the cell membrane receptors/ligands can maintain their natural conformations and bioactivity without being isolated and purified. Firstly, we screened twenty-one lactose derivatives by cell-immobilized capillary electrophoresis and obtained Gu-4 with the best activity (K = 3.58 ±â€¯0.22 × 104) targeting macrophage antigen-1 (Mac-1). Then, BCCACE was performed as follows: HEK 293 cells overexpressed with receptor (intercellular adhesion molecules-1, ICAM-1) were cultured and immobilized on the inner wall of capillaries as stationary phase, which simulated the endothelial cells lining on the inner surface of blood vessels. HEK 293 cells overexpressed with ligand Mac-1 as samples were used to simulate the neutrophils cells in blood vessels. And Gu-4 added into the running buffer solution as the antagonist was used to simulate the drug in blood. The results showed that Gu-4 (40 µM) could selectively inhibit cell-cell adhesion by targeting the interaction between Mac-1 and ICAM-1. Finally, the pharmaceutical efficacy assays of Gu-4 at cellular and animal levels were carried out using the concentration of 40 µM and the dose of 20 mg kg-1 respectively, which showed the anti-cancer metastasis activity of Gu-4 and the validity of the method. This method simulated a complete three-dimensional vascular model, which can easily obtain the suitable blood concentration of drugs. This system simulated the interaction between leukocytes and vascular endothelial cells in the bloodstream antagonized by drugs, and obtained the effective concentration of the antagonist. It can be used as an accuracy and efficient drug screening method and will be expected to become a new method to screen drugs targeting cell-cell adhesion.

9.
Sci Total Environ ; 698: 134276, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31514028

RESUMO

Polybrominated diphenyl ether (PBDE) contamination has become a major concern over the effects on human health. In the present study, we collected widely consumed green mussels (Perna viridis) samples from the northern South China Sea (NSCS) to investigate the occurrence, spatial distribution, congener profiles as well as potential risk of 18 PBDEs. All the target PBDEs were detected in green mussel samples, indicating their ubiquitous distribution. The concentrations of the total 18 PBDES (ΣPBDEs) in all samples varied from 6.96 to 55.6 ng/g lipid weight (lw), with BDE-47 and BDE-209 being the predominant PBDE congeners. Overall, the ΣPBDEs pollution in green mussels from NSCS was at a moderate to high level in comparison with the PBDEs pollution worldwide. The dietary exposure of the local population in South China to PBDEs via consuming green mussels was estimated to be 0.30-0.80 ng/kg body weight (bw)/day. Evaluation of the exposure risk for BDE-47, 99, 153 and 209 indicated that health risks due to green mussel consumption are substantially lower than the U.S. EPA minimum concern level.

10.
Cancer Commun (Lond) ; 39(1): 81, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31796105

RESUMO

BACKGROUND: High-grade glioma (HGG) is a fatal human cancer. Bortezomib, a proteasome inhibitor, has been approved for the treatment of multiple myeloma but its use in glioma awaits further investigation. This study aimed to explore the chemotherapeutic effect and the underlying mechanism of bortezomib on gliomas. METHODS: U251 and U87 cell viability and proliferation were detected by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay, tumor cell spheroid growth, and colony formation assay. Cell apoptosis and cell cycle were detected by flow cytometry. Temozolomide (TMZ)-insensitive cell lines were induced by long-term TMZ treatment, and cells with stem cell characteristics were enriched with stem cell culture medium. The mRNA levels of interested genes were measured via reverse transcription-quantitative polymerase chain reaction, and protein levels were determined via Western blotting/immunofluorescent staining in cell lines and immunohistochemical staining in paraffin-embedded sections. Via inoculating U87 cells subcutaneously, glioma xenograft models in nude mice were established for drug experiments. Patient survival data were analyzed using the Kaplan-Meier method. RESULTS: Bortezomib inhibited the viability and proliferation of U251 and U87 cells in a dose- and time-dependent manner by inducing apoptosis and cell cycle arrest. Bortezomib also significantly inhibited the spheroid growth, colony formation, and stem-like cell proliferation of U251 and U87 cells. When administrated in combination, bortezomib showed synergistic effect with TMZ in vitro and sensitized glioma to TMZ treatment both in vitro and in vivo. Bortezomib reduced both the mRNA and protein levels of Forkhead Box M1 (FOXM1) and its target gene Survivin. The FOXM1-Survivin axis was markedly up-regulated in established TMZ-insensitive glioma cell lines and HGG patients. Expression levels of FOXM1 and Survivin were positively correlated with each other and both related to poor prognosis in glioma patients. CONCLUSIONS: Bortezomib was found to inhibit glioma growth and improved TMZ chemotherapy efficacy, probably via down-regulating the FOXM1-Survivin axis. Bortezomib might be a promising agent for treating malignant glioma, alone or in combination with TMZ.

11.
J Chromatogr A ; : 460723, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31796249

RESUMO

Quantitative determination of endogenous compounds in biological samples has still been challenged by the absence of authentic blank matrix. Alternative strategy of surrogate matrix for preparing reference samples are prevalent due to its low cost and high availability. However, the evaluation system of surrogate matrix is not perfect. Herein, a novel multifunctional isotopic standards based steroidomics strategy was developed. Isotope-labeled standards were used not only as internal standards but also for the evaluation the feasibility of surrogate matrix, which improved the accuracy of assessment and could provide a new prospect for the quantitative analysis of endogenous compounds. Based on this approach, a detailed optimization from LC separation, MS detection to extraction conditions for global steroids in the steroidogenesis was firstly carried out. Characteristics and regularities of steroids in LC-MS were summarized to make references for further targeted or untargeted steroidomics study. Then eighteen steroids were quantified with high accuracy and high sensitivity in plasma from four types of cancer patients and healthy subjects using 1% BSA in PBS as surrogate matrix. And multi-steroids indexes with the best discriminating ability for lung, colorectal, breast and gastric cancer in different genders were identified successfully with Student's t-test, PLS-DA and logistic regression- ROC curve analysis. Finally, efficient cancer screening workflow was established by integrating the amine submetabolomics and lipidomics data of our previous studies. Taken together, the integrated steroidomics strategy could shed a light on the guidance for further steroidome as well as other endogenous compounds analysis and may provide a powerful tool for cancer diagnosis.

12.
Artigo em Inglês | MEDLINE | ID: mdl-31788933

RESUMO

Direct deprotonation represents an extremely simple, straightforward, and atom-economic strategy to activate the pronucleophiles bearing an acidic proton. However, the difficulty often arises while activating pronucleophiles with a low acidic proton by using conventional chiral tertiary amines. To overcome this great challenge, a handful of novel chiral Brønsted superbases, including amidines, guanidines, cyclopropenimines, and iminophosphoranes, have been discovered in recent years. This minireview mainly focuses on the application of these organosuperbases in the catalytic asymmetric reactions of low acidic pronucleophiles, and especially highlights their comparisons to the conventional tertiary amines, to demonstrate their highly efficient deprotonation processes and further stereoselectivity-controlled conversions. The advantage of these new superbases brings a great opportunity for developing more asymmetric transformations of low acidic pronucleophiles.

13.
Food Chem ; : 125892, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31791724

RESUMO

In this study, we successfully knock-out the d-hordein component of barley storage protein using RNA-guided Cas9. Mutation frequencies of 25% and 14% at two different target sites were obtained. Homozygous mutant plants that were T-DNA free were identified in the T1 generation. Barley grains without d-hordein proteins from T2 seeds showed a significantly reduced grain size compared to the parent plant and control non-edited line. The protein matrix surrounding the starch granules was increased, whereas the starch granules themselves were decreased in size in the mutant plants compared to controls. The main effect of a lack of d-hordein was a considerable decrease in the prolamines and an increase in the glutenins. The changes of other grain composition included the increased starch content, amylose content, and ß-glucan content. The roles of d-hordein mutation on barley grain size and grain composition remain to be studied.

14.
Food Funct ; 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31793606

RESUMO

We investigated the effects of Clostridium butyricum and Enterococcus faecalis (probiotics) in a piglet model. Weaned piglets (180) were randomly divided into three treatment groups and fed basal diet and basal diet supplemented with 6 × 109 CFU C. butyricum per kg and 2 × 1010 CFU E. faecalis per kg, respectively. The probiotics improved the final body weight, average daily gain, and feed conversion rate, while they reduced the diarrhea rate. The serum aspartate aminotransferase and alanine aminotransferase activities in probiotic-supplemented piglets were decreased on days 14 and 28. Piglets supplemented with probiotics presented an increased serum immunoglobulin (Ig)M level on day 14 and IgA, IgG, and IgM levels on day 28 compared with control piglets, respectively. Moreover, the probiotics increased the jejunal villus length and jejunal villus height to crypt depth ratio, while they decreased the jejunal crypt depth compared with those of the control. Similarly, an increase in inflammation-related pathway factor expression was observed after probiotic administration. Piglets supplemented with probiotics had a higher concentration of volatile fatty acids in the colonic contents than that in the control. High-throughput sequencing indicated that the probiotics modulated the colon bacterial diversity. Species richness and the alpha diversity index of bacterial samples in probiotic-supplemented piglets were higher than those in the control. Piglets supplemented with C. butyricum presented a considerably high relative abundance of C. butyricum compared with that in the control. Overall, C. butyricum and E. faecalis can promote growth performance, protect the intestinal villi morphology, improve immunity, and optimize the intestinal flora in weaned piglets.

15.
Artigo em Inglês | MEDLINE | ID: mdl-31793624

RESUMO

CONTEXT: Sex hormone-binding globulin (SHBG), a homodimeric glycoprotein produced by hepatocytes has been shown to be associated with metabolic disorders. Whether circulating SHBG levels are predictive of later risk of non-alcoholic fatty liver disease (NAFLD) remains unknown. In this study, we prospectively investigated the association between SHBG and NAFLD progression through a community-based cohort comprising 3,389 Chinese adults. METHODS: NAFLD was diagnosed using abdominal ultrasonography. Serum SHBG levels were measured by chemiluminescent enzyme immunometric assay, and their relationship with NAFLD development and regression was investigated after a mean follow-up of 3.09 years using multivariable logistic regression. RESULTS: Basal SHBG was negatively associated with NAFLD development, with a fully adjusted odds ratio (OR) and its 95% confidence interval (CI) of 0.22 (0.12-0.40) (P-trend < 0.001). In contrast, basal SHBG was positively associated with NAFLD regression, with a fully adjusted OR of 4.83 (2.38-9.81) (P-trend < 0.001). Multiple-stepwise logistic regression analysis showed that SHBG concentration was an independent predictor of NAFLD development (OR, 0.28 [0.18-0.45]; P < 0.001) and regression (OR, 3.89 [2.43-6.22]; P < 0.001). In addition, the area under the receiver operating characteristic curves were 0.764 (95% CI, 0.740-0.787) and 0.762 (95% CI, 0.738-0.785) for the prediction models of NAFLD development and regression, respectively. CONCLUSIONS: Serum SHBG concentration is associated with the development and regression of NAFLD; moreover, it can be a potential biomarker for predicting NAFLD progression, and also a novel preventive and therapeutic target for NAFLD.

16.
Sensors (Basel) ; 19(23)2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31801195

RESUMO

In extant radar signal processing systems, detection and tracking are carried out independently, and detected measurements are utilized as inputs to the tracking procedure. Therefore, the tracking performance is highly associated with detection accuracy, and this performance may severely degrade when detections include a mass of false alarms and missed-targets errors, especially in dense clutter or closely-spaced trajectories scenarios. To deal with this issue, this paper proposes a novel method for integrating the multiple hypothesis tracker with detection processing. Specifically, the detector acquires an adaptive detection threshold from the output of the multiple hypothesis tracker algorithm, and then the obtained detection threshold is employed to compute the score function and sequential probability ratio test threshold for the data association and track estimation tasks. A comparative analysis of three tracking algorithms in a clutter dense scenario, including the proposed method, the multiple hypothesis tracker, and the global nearest neighbor algorithm, is conducted. Simulation results demonstrate that the proposed multiple hypothesis tracker integrated with detection processing method outperforms both the standard multiple hypothesis tracker algorithm and the global nearest neighbor algorithm in terms of tracking accuracy.

17.
Artigo em Inglês | MEDLINE | ID: mdl-31706651

RESUMO

The design of electrocatalysts with cost-efficient, highly-efficient and stable for hydrogen evolution reaction (HER) is significant to alleviate energy crisis in the future. Herein, we prepared the Ni11(HPO3)8(OH)3/Mn3O4 (named as NiPi/Mn3O4) composite with crystalline/amorphous interface by electrochemical activation based on Ni3P/MnOOH precursor. The precursor was synthesized by two-step method that firstly electrodeposited on nickel foam and then used anodic oxidation under the applied voltage. The XPS analysis manifested that NiPi/Mn3O4 had a strong interface coupling between Ni11(HPO3)8(OH)3 and Mn3O4 contributed to fast kinetics of hydrogen evolution reaction. The morphology of the nanowires and nanoparticles were provided lager contact area between catalyst and electrolyte. Meanwhile, the obvious interface between crystalline and amorphous also resulted in NiPi/Mn3O4 heterostructureted material with faster electron transport and superior stability. Owing to these characteristics, the NiPi/Mn3O4 displays amazing HER activity with low overpotential of 84 mV at 100 mA cm-2 and a long-term stability of over 100 h at 200 mA cm-2 in 1.0 M NaOH solution. The surprising activity of NiPi/Mn3O4 is better than that of most reported catalysts, similar to the state-of-the-art Pt/C.

18.
Kidney Int ; 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31685310

RESUMO

Innate lymphoid cells are a recently recognized group of immune cells with critical roles in tissue homeostasis and inflammation. Regulatory innate lymphoid cells are a newly identified subset of innate lymphoid cells, which play a suppressive role in the innate immune response, favoring the resolution of intestinal inflammation. However, the expression and role of regulatory innate lymphoid cells in kidney has not been reported. Here, we show that regulatory innate lymphoid cells are present in both human and mouse kidney, express similar surface markers and form a similar proportion of total kidney innate lymphoid cells. Regulatory innate lymphoid cells from kidney were expanded in vitro with a combination of IL-2, IL-7 and transforming growth factor-ß. These cells exhibited immunosuppressive effects on innate immune cells via secretion of IL-10 and transforming growth factor-ß. Moreover, treatment with IL-2/IL-2 antibody complexes (IL-2C) promoted expansion of regulatory innate lymphoid cells in vivo, and prevent renal ischemia/reperfusion injury in Rag-/- mice that lack adaptive immune cells including Tregs. Depletion of regulatory innate lymphoid cells with anti-CD25 antibody abolished the beneficial effects of IL-2C in the Rag-/- mice. Adoptive transfer of ex vivo expanded regulatory innate lymphoid cells improved renal function and attenuated histologic damage when given before or after induction of ischemia/reperfusion injury in association with reduction of neutrophil infiltration and induction of reparative M2 macrophages in kidney. Thus, our study shows that regulatory innate lymphoid cells suppress innate renal inflammation and ischemia/reperfusion injury.

19.
Org Lett ; 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31710502

RESUMO

An unprecedented copper-catalyzed tandem cross-coupling/[2 + 2] cycloaddition of 1,6-allenynes with diazo compounds was reported, chemo- and regioselectively providing 3-azabicyclo[5.2.0] frameworks in moderate to excellent yields under mild reaction conditions. Moreover, the products readily convert to highly functionalized quinolines via oxidative radical rearrangement.

20.
Artigo em Inglês | MEDLINE | ID: mdl-31718979

RESUMO

Identifying and detecting similar target cations through combining "turn on" and "turn off" fluorescence mechanism is effective and challenging. Now a new colorimetric and ON-OFF-ON fluorescent probe N'-((7-(diethylamino)-2-oxo-2H-chromen-3-yl)methylene)-3-hydroxy-2-naphthohydrazide (L) was reported, which could detect Cu2+ and Co2+ in phosphate buffered CH3CH2OH-H2O solvent system. With the assistance of glutathione and pH adjustment, a unique ON-OFF-ON fluorescence detection strategy could be achieved for distinguishing Cu2+ and Co2+. The emission of probe could recover from the L-Cu2+ and L-Co2+ system by addition of GSH or adjusting pH value to 4, respectively, which is due to the abolishment of paramagnetic Cu2+/Co2+. Based on fluorescence titration experiments, the limit of detection was determined as 3.84 × 10-9 M and 4.55 × 10-9 M for Cu2+ and Co2+, respectively. Meanwhile, the detection limit reached 6.21 × 10-8 M for Cu2+ and 6.96 × 10-8 M for Co2+ according to absorbance signal output. Fast recognition of Cu2+/Co2+ can be achieved by obvious color changes from green to colorless under UV light, as well as from yellow to orange-red in room light. The binding mode of L toward Cu2+ and Co2+ have been systematically studied by Job's plot analysis, ESI-MS, IR and density functional theory calculations. Most strikingly, further practical applications of the probe L in fluorescence imaging were investigated in MCF-7 cells and zebrafish due to its low cytotoxicity and good optical properties, suggesting that L could serve as a fluorescent sensor for tracking Cu2+ and Co2+in vivo.

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