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1.
Exp Cell Res ; : 111812, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31917202

RESUMO

The properties and number of neural stem cells (NSCs) in neural tissue are important issues for the regenerative capacity of the spinal cord in different organisms or developmental stages. In this study, we investigated the self-renewal and differentiation potential of NSCs from adult spinal cords of adult geckos (Gecko japonicus) and mice. The sphere forming ratio of mouse NSCs was higher than that of gecko NSCs, and the sphere forming time of mouse NSCs was shorter as well. In addition, serum-induced differentiation of NSCs gave rise to more ß-tubulin III (TUBB3)-positive progeny in geckos, whereas NSCs gave rise to more glial fibrillary acidic protein (GFAP)-positive cells in mice. We further conducted single sphere RNA-seq for both gecko and mouse NSCs, and transcriptome data revealed that purified NSC populations form either geckos or mice are heterogeneous and stay at various differentiated stages even with similar appearance. Mouse NSCs expressed more glial markers and gecko NSCs expressed more neuronal markers, which is consistent with cell fate determination of mouse and gecko NSCs in differentiation assays.

2.
Mater Sci Eng C Mater Biol Appl ; 108: 110512, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31924017

RESUMO

980-nm-upconverted 530 and 550 nm Er3+ green fluorescence spectra of Er3+/Yb3+-codoped NaGd(WO4)2 submicron crystals were measured in the temperature range of 298-383 K. A sextuple ratiometric thermometry is proposed. It is established on the basis of six schemes of fluorescence intensity ratio (FIR) that considers three component peaks of the 530 nm emission band and two component peaks of the 550 nm emission band, which involve electronic transitions between two Stark sublevels of Er3+. The study shows that the phosphor shows strong green fluorescence, which is verified by measured quantum yield, and thermally stable spectral structure desired for the sextuple ratiometric thermometry. All of the six FIR schemes display highly efficient sensing performances with slightly different thermal sensitivities. Each scheme gives a temperature value and the six schemes give an averaged result. In parallel, we have also carried out an ex vivo experimental study on the temperature characteristics of the green fluorescence of the phosphor. Almost same results have been obtained, verifying biological applicability of the phosphor. The ex vivo experimental results also show that the sextuple thermometry increases considerably the accuracy and reliability of temperature measurement in comparison with the conventional intensity integration method.

3.
J Cell Biochem ; 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31904151

RESUMO

Although many methods and new therapeutic drugs have been developed, the overall survival rate and long-term survival rate of patients with gastric cancer (GC) are still not satisfactory. In this study, we investigated the effects of microRNA miR-133a-3p and transcription factor FOXP3 on proliferation and autophagy of GC cells and their interactions. Our results showed that knockdown of FOXP3 increased the proliferation and autophagy of GC cells. The relationship between FOXP3 and autophagy has not been reported previously. In addition, FOXP3 could directly bind the promoter region of TP53 and inhibit its expression. miR-133a-3p increased the proliferation and autophagy via decreasing the protein level of FOXP3 by targeting its 3'-UTR. Our research provides new insights into the development of GC and provides new ideas and theoretical basis for the clinical treatment of GC and the development of new drug targets.

4.
Mikrochim Acta ; 187(1): 94, 2020 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-31902014

RESUMO

Poly(3,4-ethylenedioxythiophene) (PEDOT) films were electrodeposited by cyclic voltammetry on a glassy carbon electrode (GCE) in aqueous solution. Three kinds of supporting electrolytes were used, viz. graphene oxide (GO), phosphate buffered saline (PBS), and GO in PBS, respectively. The surface morphology of the modified electrodes was characterized by scanning electron microscopy. The electrochemical performance of the modified electrodes was investigated by cyclic voltammetry and electrochemical impedance spectroscopy by using the hexacyanoferrate redox system. The results demonstrate that the PEDOT-GO/GCE, which was electropolymerized in aqueous solutions containing EDOT and GO, shows the best electrochemical activities compared with other modified electrodes. The electrochemical behaviors of ascorbic acid (AA), dopamine (DA) and uric acid (UA) were investigated by cyclic voltammetry. The PEDOT-GO/GCE exhibits enhanced electrocatalytic activities towards these important biomolecules. Under physiological pH conditions and in the mixed system of AA, DA and UA, the modified GCE exhibits the following figures of merit: (a) a linear voltammetric response in the concentration ranges of 100-1000 µM for AA, 6.0-200 µM for DA, and 40-240 µM for UA; (b) well separated oxidation peaks near 31, 213 and 342 mV (vs. saturated Ag/AgCl) for AA, DA and UA, respectively; and (c) detection of limits (at S/N = 3) of 20, 2.0 and 10 µM. The results demonstrate that GO, based on its relatively large number of anionic sites, can be used as the sole weak electrolyte and charge balance dopant for the preparation of functionally doped conducting polymers by electrodeposition. Graphical abstractSchematic representation of a nanostructure composed of hybrid conducting polymer PEDOT-GO nanocomposites, and its application to simultaneous determination of ascorbic acid, dopamine and uric acid.

5.
FASEB J ; 34(1): 1768-1782, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31914650

RESUMO

Interleukin-18 (IL-18) has been demonstrated to augment the antitumor capacity of chimeric antigen receptor-T cells (CAR-T) but the underlying mechanisms are largely unknown. Here we explored the effects and mechanisms of exogenous IL-18 on the antitumor response of CAR-T cells. IL-18 boosted the cytotoxicity of human epidermal growth factor receptor-2 (HER2)-specific CAR-T cells ex vivo and enhanced the antitumor efficacy of the CAR-T cells in immunodeficient mice, moreover, IL-18 improved the antitumor capacity of OVA-specific T cells in immunocompetent mice, indicating the universal enhancing function of IL-18 for adoptive cell therapy. To address the roles of IL-18 receptor (IL-18R) in the enhancing function, we evaluated the effects of IL-18R knockout (IL-18R-/-) condition in immunocompetent host and CAR-T cells on the IL-18-enhanced antitumor activities. Interestingly, IL-18 persisted to improve the antitumor ability of IL-18R intact CAR-T cells in IL-18R-/- mice. For IL-18R-/- CAR-T cells, however, IL-18 still holds the enhancing ability to boost the antitumor efficacy in IL-18R-/- mice, albeit the ex vivo tumor-killing ability was lower than that of IL-18R intact CAR-T cells, indicating that IL-18R-independent pathway is involved in the enhancement. Furthermore, tagged IL-18 binded to the membrane of IL-18R-/- splenic and lymph node cells and IL-18R intact and IL-18R-/- CAR-T cells showed distinct transcriptomic profiles when stimulated by IL-18. These data demonstrate that IL-18R-independent pathways contribute to functions of IL-18.

6.
Artigo em Inglês | MEDLINE | ID: mdl-31894364

RESUMO

Marine microorganisms live in dramatically different environments and have attracted much attention for their structurally unique natural products with potential strong biological activity. Based on the one strain-many compounds (OSMAC) strategy and liquid chromatography mass spectrometry (LC-MS) methods, our continuing efforts on the investigation of novel active compounds from marine Verrucosispora sp. MS100137 has led to the identification of a new polycyclic metabolite, abyssomicin Y (1), together with six known abyssomicin and proximicin analogs (2-7). Abyssomicin Y is a type I abyssomicin with an epoxide group at C-8 and C-9. Compounds 1-3 showed potent inhibitory effects against the influenza A virus; their observed inhibition rates were 97.9%, 98.3%, and 95.9%, respectively, at a concentration of 10 µM, and they displayed lower cytotoxicity than 4. The structures were determined by different NMR techniques and HRMS experiments. This investigation revealed that OSMAC could serve as a useful method for enabling the activation of the silent genes in the microorganism and for the formation of previously unreported active secondary metabolites.

7.
Microbiol Resour Announc ; 8(50)2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31831614

RESUMO

As an opportunistic pathogen, Citrobacter freundii is involved in a wide spectrum of nosocomial infections. C. freundii phages may prove useful as therapeutics for treating infections caused by multidrug-resistant C. freundii strains. Here, we report the complete genome sequence of C. freundii siphophage Sazh, which is closely related to Enterobacteria phages T1 and TLS.

8.
Ying Yong Sheng Tai Xue Bao ; 30(11): 3681-3688, 2019 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-31833680

RESUMO

To understand the effects of climate warming on rhizosphere ecological processes in the alpine scrub ecosystem, the responses of polyphenoloxidase and catalase activities in the rhizosphere and bulk soils to experimental warming (1.3 ℃) were examined during the growing season in a Sibiraea angustata scrub ecosystem on the eastern Qinghai-Tibetan Plateau, China. The results showed that the activities of polyphenoloxidase in rhizosphere and bulk soils in the middle growing season were significantly higher than those in the early or late growing season. The activities of catalase in the bulk soil increased gradually during the growing season, while they showed no seasonal changes in the rhizosphere soil. In the bulk soil, warming significantly increased the activity of polyphenoloxidase by 17.5% in the late growing season and increased that of catalase by 2.2% in the middle growing season, whereas it did not affect soil enzyme activities in early or late growing seasons. In the rhizosphere soil, warming only significantly increased the activities of polyphenoloxidase and catalase by 6.5% and 1.3% in the early growing season. The rhizosphere effect of soil polyphenoloxidase activity was positive throughout the growing season, while there was no obvious rhizosphere effect for soil catalase activity. Furthermore, warming significantly decreased the rhizosphere effect of soil polyphenoloxidase activity by 15.2% during the late growing season. These results indicated that the activities of polyphenoloxidase and catalase activities differed between rhizosphere and bulk soils, with consequences on the rhizosphere soil ecological processes under climate warming in the alpine scrub ecosystem on the eastern Qinghai-Tibetan Plateau.

9.
Mikrochim Acta ; 187(1): 46, 2019 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-31838593

RESUMO

A fluorometric assay is described for ochratoxin A (OTA) using an aptamer. The method is based on exonuclease-assisted recycling amplification. The OTA-binding aptamer partially hybridizes with complementary DNA (cDNA) that is released when the aptamer recognizes OTA. Then, cDNA hybridizes with a specifically designed hairpin DNA. Next, short ssDNA and cDNA are, respectively, released by exonuclease III catalyzed hydrolysis of the dsDNA. The cDNA induces the next ring opening and digestion. The short ssDNA captures the sDNA that is labeled with fluorescent FAM and is absorbed on graphene oxide (GO). The green fluorescence of the sDNA/GO system is quenched but is recovered if the sDNA is released from GO. This assay is high sensitive, works in the 5 nM to 200 nM OTA concentration range and has a 0.96 nM lower detection limit. It was applied to the quantitation of OTA in spiked wine and coffee samples. Graphical abstractSchematic of a fluorometric assay based on exonuclease-assisted recycling amplification for quantitative monitoring of OTA without the need of sample separation and multiple washing steps.

10.
Sensors (Basel) ; 19(24)2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31817517

RESUMO

A portable capacitive sensor was designed to assess frying oil degradation by measuring the changes in electrical capacitance. An interdigital electrode (IDE) was designed to be implemented as the testing probe (as IDEs are resistive to parasitic capacitance), together with an adjacent capacitive chip Pcap01 and a further microprocessor STM32, which were used as the data-processing elements. Experimental results demonstrated that viscosity could be a useful frying oil quality indicator, and also proved a preliminary correlation between IDE capacitance and oils' total polar materials. This implies that IDE capacitance could be a suitable metric for conveniently assessing frying oil degradation. The designed capacitance sensor is light in weight, cost effective, and has excellent potential for simple, inexpensive, on-the-spot testing of the current quality of frying oil.

11.
Micromachines (Basel) ; 10(12)2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31817762

RESUMO

Reports on measurements of the rotational velocity by using giant magnetoimpedance sensors are rarely seen. In this study, a rotational-velocity sensing system based on giant magnetoimpedance (GMI) effect was established to measure rotational velocities of brushless direct-current motors. Square waves and sawtooth waves were observed due to the rotation of the shaft. We also found that the square waves gradually became sawtooth waves with increasing the measurement distance and rotational velocity. The GMI-based rotational-velocity measurement results (1000-4300 r/min) were further confirmed using the Hall sensor. This GMI sensor is capable of measuring ultrahigh rotational velocity of 84,000 r/min with a large voltage response of 5 V, even when setting a large measurement distance of 9 cm. Accordingly, the GMI sensor is very useful for sensitive measurements of high rotational velocity.

12.
J Athl Train ; 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31876455

RESUMO

CONTEXT: Subacromial impingement syndrome (SIS) is associated with scapular dyskinesis, or imbalanced scapular muscle activity. Evidence has shown that feedback can improve scapular control in patients with SIS. However, it is unknown whether real-time video feedback or electromyography (EMG) biofeedback is optimal for improving scapular kinematics and muscle activity during a functional task. OBJECTIVE: To compare the effects of video and EMG feedback sessions on absolute muscle activity (upper trapezius [UT], lower trapezius [LT], serratus anterior), muscle balance ratios (UT/LT, UT/serratus anterior), and scapular kinematics (anterior/posterior tilt, external/internal rotation, upward rotation) in SIS participants during arm elevation and lowering. DESIGN: Randomized controlled clinical trial. SETTING: Research laboratory. PATIENTS OR OTHER PARTICIPANTS: Overhead athletes who were diagnosed with SIS and who also exhibited scapular dyskinesis (N = 41). MAIN OUTCOME MEASURE(S): Three-dimensional kinematics and EMG were recorded before and after feedback training. RESULTS: Lower trapezius muscle activity increased (4.2%-18%, P < .011) and UT/LT decreased (0.56-1.17, P < .013) in the EMG biofeedback training group as compared with those in the video feedback training group. Scapular upward rotation during arm elevations was higher in the video group than in the EMG group after feedback training (2.3°, P = .024). CONCLUSIONS: The EMG biofeedback improved muscle control and video feedback improved the correction of scapular upward rotation in patients with SIS. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov: NCT03252444.

13.
Prostaglandins Other Lipid Mediat ; 146: 106402, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31841664

RESUMO

Although C6-Ceramide has attracted much attention as a possible tumor suppressor, the delivery of C6-Ceramide is still challenging due to its inherent hydrophobicity and insolubility. In this study we explored the use of a natural compound rubusoside (RUB) as a solubilizer to enhance the solubility of a fluorescence-labeled C6-Ceramide (NBD C6-Ceramide) and to characterize its pharmacokinetics and tissue distribution in an animal model. RUB significantly enhanced the solubility of NBD C6-Ceramide by forming nanomicelles, and efficiently delivered NBD C6-Ceramide in rats by oral and intravenous administration. RUB loaded 1.96 % of NBD C6-Ceramide in the nanomicelles and solubilized it to a concentration of 3.6 mg/mL in water. NBD C6-Ceramide in nanomicelles remained stable in aqueous solutions, allowing intravenous administration without the use of any organic solvents or surfactants. After oral administration, NBD C6-Ceramide rapidly rose to peak plasma concentrations within the first 90 min, distributed to tissues, and remained in vivo for more than 24 h. Tissular levels of NBD C6-Ceramide from high to low were associated with heart, lung, cerebellum, testicle, spleen, liver, kidney, and brain. Altogether, our study demonstrated that RUB-assisted nanomicelles can serve as an efficient and convenient delivery system for short-chain C6-Ceramide and enable in vivo evaluation of potential new cancer treatments.

15.
Microbiol Resour Announc ; 8(44)2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31672751

RESUMO

Klebsiella pneumoniae is an opportunistic pathogen that is the cause of several hospital-acquired infections. Bacteriophages that target this bacterium could be used therapeutically as novel antimicrobial agents. Here, we present the complete genome sequence of the T1-like K. pneumoniae phage Sanco.

16.
Front Oncol ; 9: 1110, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31696058

RESUMO

Expression patterns of estrogen receptors [ERα, ERß, and G-protein associated ER (GPER)] in melanoma and skin may suggest their differential roles in carcinogenesis. Phytoestrogenic compound cyanidin-3-o-glucoside (C3G) has been shown to inhibit the growth and metastatic potential of melanoma, although the underlying molecular mechanism remains unclear. The aim of this study was to clarify the mechanism of action of C3G in melanoma in vitro and in vivo, as well as to characterize the functional expressions of ERs in melanoma. In normal skin or melanoma (n = 20/each), no ERα protein was detectable, whereas expression of ERß was high in skin but weak focal or negative in melanoma; and finally high expression of GPER in all skin vs. 50% melanoma tissues (10/20) was found. These results correspond with our analysis of the melanoma survival rates (SRs) from Human Protein Atlas and The Cancer Genome Atlas GDC (362 patients), where low ERß expression in melanoma correlate with a poor relapse-free survival, and no correlations were observed between SRs and ERα or GPER expression in melanoma. Furthermore, we demonstrated that C3G treatment arrested the cell cycle at the G2/M phase by targeting cyclin B1 (CCNB1) and promoted apoptosis via ERß in both mouse and human melanoma cell lines, and inhibited melanoma cell growth in vivo. Our study suggested that C3G elicits an agonistic effect toward ERß signaling enhancement, which may serve as a potential novel therapeutic and preventive approach for melanoma.

17.
Cell Mol Neurobiol ; 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31696374

RESUMO

The original version of this article unfortunately contained an error in Figures 1A and 4C.

18.
Coron Artery Dis ; 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31703014

RESUMO

BACKGROUND: Several studies have evaluated the long-term clinical outcomes of periprocedural myocardial injury for chronic total occlusions patients. However, the results of these studies were inconsistent. To determine whether the periprocedural myocardial injury has adverse effects on long-term clinical outcomes in chronic total occlusion patients undergoing percutaneous coronary intervention. METHODS: We searched Cochrane Library, PubMed, and Embase for eligible articles from their date of inception up to March 2019. Long-term clinical outcomes included major adverse cardiac events, all-cause death, cardiac death, myocardial infarction, and target vessel revascularization. Odds ratios with 95% confidence intervals were calculated as summary statistics by using Review Manager software. RESULTS: A total of 8 observational studies involving 5879 chronic total occlusions patients were included in this meta-analysis. These results of this meta-analysis indicated that periprocedural myocardial injury was associated with a higher risk of major adverse cardiac events (odds ratio, 1.94; 95% confidence interval, 1.22-3.08; P = 0.005), a higher risk of all-cause death (odds ratio, 1.30; 95% confidence interval, 1.02-1.64; P = 0.03), a higher risk of cardiac death (odds ratio, 2.59; 95% confidence interval, 1.41-4.78; P = 0.002), a higher risk of myocardial infarction (odds ratio, 3.07; 95% confidence interval, 1.90-4.98; P < 0.00001), and a higher risk of target vessel revascularization (odds ratio, 2.07; 95% confidence interval, 1.35-3.16; P=0.0008) than non-periprocedural myocardial injury. CONCLUSION: Periprocedural myocardial injury was associated with significantly increased risk of major adverse cardiac events, all-cause death, cardiac death, myocardial infarction, and target vessel revascularization in chronic total occlusion patients undergoing percutaneous coronary intervention at long-term follow-up.

19.
Cardiovasc Res ; 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31774487

RESUMO

AIM: Pulmonary arterial hypertension (PAH) is a pathophysiological syndrome associated with pulmonary/systemic inflammation. Melatonin relieves PAH, but the molecular mode of action remains unclear. Here, we investigated the role of melatonin in normalizing vascular homeostasis. METHODS AND RESULTS: Light-time mean serum melatonin concentration was lower in patients with PAH than in normal controls (11.06 ± 3.44 (7.13-15.6) vs. 14.55 ± 1.28 (8.0-19.4) pg/ml), which was negatively correlated with increased serum levels of interleukin-1ß (IL-1ß) in patients with PAH. We showed that inflammasomes were activated in the PAH mice model and that melatonin attenuated IL-1ß secretion. On one hand, melatonin reduced the number of macrophages in lung by inhibiting the endothelial chemokines and adhesion factors. Moreover, use of Il1r-/- mice, Caspase1/11-/- mice and melatonin-treated mice revealed that melatonin reduced hypoxia-induced vascular endothelial leakage in the lung. On the other hand, we verified that melatonin reduced the formation of inflammasome multiprotein complexes by modulating calcium ions in macrophages using a live cell station, and melatonin decreased inositol triphosphate and increased cAMP. Furthermore, knockdown of melatonin membrane receptors blocked melatonin function, and a melatonin membrane receptors agonist inactivated inflammasomes in macrophages. CONCLUSIONS: Melatonin attenuated inflammasome-associated vascular disorders by directly improving endothelial leakage and decreasing the formation of inflammasome multiprotein complexes in macrophages. Taken together, our data provide a theoretical basis for applying melatonin clinically, and inflammasomes may be a possible target of PAH treatment. TRANSLATIONAL PERSPECTIVE: PAH is a pathophysiological syndrome associated with inflammation. Our study is the first to report a decrease in melatonin levels in patients with PAH, which provides insight to investigate melatonin or other circadian rhythm-related factors in the etiology of PAH. We demonstrate that melatonin improved PAH by inactivating inflammasome in the lungs of several mice models. The fact that melatonin is an endogenous hormone, may present an advantage for PAH therapy. Our data provide a theoretical basis for applying melatonin clinically, and inflammasomes may be a possible target of PAH treatment.

20.
J Biomed Nanotechnol ; 15(12): 2393-2400, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31748019

RESUMO

Hepatitis B virus (HBV) is closely related to occurrence and development of viral hepatitis. A mutation of 1896nt locus in its pre-C region can promote replication of HBV DNA and improve stability of pre-genome RNA structure, and can even help HBV evade immune clearance. In this study, magnetic beads-probe (MBs@probe) method, combined with single base extension (SBE) technology, was developed for in-situ mutation detection of HBV pre-C region 1896nt locus. Before successfully completing the genotyping of 165 HBV samples, the crucial reaction conditions were first optimized, such as SBE temperature, MBs size and amount, and probe concentration on the surface of MBs. Experimental results showed that these conditions had significant effects on MBs@probe in-situ mutation detection. Comprehensive considerations, such as 58 °C of SBE temperature, high fluorescence intensity and signal-to-noise ratios (SNRs) were obtained when MBs@probe complex was made by 100 µg of 300 nm-MBs and 3.0 µM of probes in the system. Finally, 1896nt locus mutation in pre-C region of 165 HBV samples was successfully genotyped, among which 71 HBV samples were wild types and the remaining 94 samples were mutant types. Meanwhile, 14 randomly chosen samples were taken to further analyze fluorescence intensity and SNRs respectively, and sequencing results for the first two samples were consistent with results from the MBs@probe in-situ mutation detection method. Compared with two-color fluorescence hybridization (TCFH) genotyping technology, this method generally improves the SNRs to more than 10 (which is more than 2-fold), has higher reliability and is more suitable to detect SNPs for known sites.


Assuntos
Vírus da Hepatite B , Herpesvirus Cercopitecino 1 , Polimorfismo de Nucleotídeo Único , DNA Viral , Genótipo , Hepatite B , Humanos , Mutação , Reprodutibilidade dos Testes
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