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1.
Mol Cell ; 78(3): 371-373, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32386538

RESUMO

Yoshida et al. (2020) report in this issue of Molecular Cell that a paternal low-protein diet elevates ROS in the testicular germ cells, altering ATF7 activity and H3K9me2 abundance on target genes, including tRNA loci. These changes are maintained in spermatozoa, regulating tsRNA biogenesis, and together transmit intergenerational effects.

2.
Wound Repair Regen ; 2020 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-32304258

RESUMO

Current wound scaffold dressing constructs can facilitate wound healing but do not exhibit antibacterial activity, resulting in high infection rates. We aimed to endow wound scaffold dressing with anti-infective ability by polyhexamethylenebiguanide (PHMB). We prepared PHMB hydrogel at varying concentrations (0.25%, 0.5%, 1%, 2%) and assessed release and cytotoxicity. PHMB hydrogel was added to the wound scaffold dressing to generate a PHMB hydrogel-modified wound scaffold dressing. Wound healing and infection prevention were evaluated using a full-thickness skin defect model in rats. In vitro, the hydrogel PHMB release time positively correlated with PHMB concentration, with 1% allowing sufficiently long release time to encompass the high-incidence period (3-5d) of infection following wound scaffold dressing implantation. Implantation of 1% PHMB hydrogel into the skin did not cause adverse responses. In vitro cytotoxicity assays showed the PHMB hydrogel-modified wound scaffold dressing did not significantly affect proliferation of fibroblasts or vascular endothelial cells, 99.90% vs 99.84% for fibroblasts and 100.21% vs 99.28% for vascular endothelial cells at 21d. Transplantation of PHMB hydrogel-modified wound scaffold dressing/unmodified wound scaffold dressing on the non-infected wounds of rats yielded no significant difference in relative vascularization rate, 47.40 vs 50.87 per view at 21d, whereas bacterial content of the wound tissue in the PHMB hydrogel-modified wound scaffold dressing group was significantly lower than the unmodified wound scaffold dressing group, (1.80 ± 0.35) × 103 vs (9.34 ± 0.45) × 103 at 14d. Prevalence of persistent wound infection in the rats receiving PHMB hydrogel-modified wound scaffold dressing transplantation onto infected wounds was significantly lower than the unmodified wound scaffold dressing group, 30% vs 100%. PHMB hydrogel-modified wound scaffold dressing exhibited suitable antibacterial ability, and its biological activity did not significantly differ from that of the unmodified wound scaffold dressing, thereby allowing it to effectively prevent infection following wound scaffold dressing implantation. This article is protected by copyright. All rights reserved.

3.
J Mol Graph Model ; 98: 107600, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32248075

RESUMO

As so far, the development and application prospects of transition metal silicon-based materials have received the considerable attention. V-Si silicides are one of the most important silicon-based high-temperature materials. Brittle behavior hinders their wide application. In present work, the influence of vackancies on mechanical properties, brittle/ductile behavior and electronic properties of V5Si3 silicides is studied using the first-principles calculations. The vacancy formation energy, elastic constants, elastic modulus, brittle/ductile behavior and electronic behavior of the perfect V5Si3 and V5Si3 with vacancies were comparatively calculated and discussed, respectively. The thermodynamic data and phonon frequencies demonstrate that the V5Si3 with different vacancies can exhibit the structural stability. Although the vacancies weaken the hardness of V5Si3, the vacancies improve the brittle behavior of the parent V5Si3. Especially, the Si-Va1 and Si-Va2 vacancies in V5Si3 induced brittle-to-ductile transition for V5Si3 desilicides. The electronic structures explain the mechanism of the difference of mechanical properties for different vacancies.

4.
Biomed Res Int ; 2020: 5282949, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32185208

RESUMO

Honeydew melon (Cucumis melo L.) is an oval-shaped delicious fruit of one cultivar group of the muskmelon with immense nutritional importance and is extensively consumed by many tropical countries. The effect of various organic solvents on the recovery of phytochemicals from honeydew melon plant fruits and seeds was assessed. Further, High-Performance Liquid Chromatography (HPLC) was used to examine and assess the contents of phenolic acid (gallic acid) and flavonoid (rutin) compounds. The use of gas chromatography-mass spectrometry (GC-MS) analysis explained the presence of volatile phytocompounds in the extracts. The use of organic solvents had a substantial impact on the total dry weight and extract yield. In general, the solvent-extracted constituents remained in the order of methanol>chloroform>distilled water for both honeydew melon seeds and whole fruit. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) was used to assess the cytotoxicity effect against PC3, HCT116, HeLa, and Jurkat cell lines. The chloroform extract exhibited a good cytotoxic activity against all cell lines as compared to other solvent extracts. HPLC analysis revealed the occurrence of gallic acid content of 0.102 ± 0.23 mg/10 mg of dry whole fruit extract, while 10 mg of dry seed extract contained only 0.022 ± 0.12 mg of gallic acid content. Likewise, rutin content was observed to be 0.224 ± 0.31 mg and 0.1916 ± 0.82 mg/10 mg of dry whole fruit and seed extract, respectively. Further, GC-MS analysis revealed the presence of a total of 37 compounds in chloroform extract of whole fruit, while only 14 compounds were found in seed extract. Nevertheless, more examinations are needed to identify and characterize other metabolites from honeydew melon and evaluate their pharmacological importance.

5.
Drug Des Devel Ther ; 14: 275-284, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32158186

RESUMO

Purpose: Treatment options for relapsed or refractory diffuse large B-cell lymphoma (RR DLBCL) represent an unmet medical need. Apatinib is a new oral tyrosine kinase inhibitor mainly targeting vascular endothelial growth factor receptor-2 (VEGFR-2) to inhibit tumour angiogenesis. In the present study, we evaluated the efficacy and safety of apatinib for patients with RR DLBCL. Patients and Methods: In this phase II, open-label, single-arm, prospective study, we enrolled patients aged 14-70 years with treatment failure of at least two chemotherapeutic regimens using Simon's two-stage design. All patients were administered apatinib at an initial dose of 500 mg on a 4-week cycle at home and visited the outpatient clinic every two cycles to evaluate efficacy and to record adverse events. We considered objective response rate (ORR) as the primary end point, and progression-free survival (PFS), and overall survival (OS) plus duration of response (DoR) as the secondary end point. (This trial was registered at ClinicalTrials.gov, identifier: NCT03376958.). Results: From January 2017 to February 2019, we screened 35 patients and enrolled 32 eligible patients. At the cutoff point (April 2019), we noted 2 (6.3%) complete responses, 12 (37.5%) partial responses, and 9 (28.1%) stable diseases, attributing to an ORR of 43.8% and a disease control rate of 71.9%. The median PFS and OS were 6.9 (95% confidence interval [CI], 5.8-7.9) and 7.9 months (95% CI, 7.0-8.7), respectively. The median DoR was 5.0 months (95% CI, 3.5-6.5) for patients who achieved PR. The most common grade 3-4 adverse events (AE) were hypertension (12.6%), hand-foot syndrome (9.4%), and leucopenia (6.3%). No apatinib-related deaths were noted. Conclusion: Home administration of apatinib shows promising efficacy and manageable AEs in patients with RR DLBCL.

6.
Biochem Biophys Res Commun ; 525(3): 662-667, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32127173

RESUMO

Insulin resistance (IR) is an important pathological basis of obesity, diabetes and cardiovascular diseases, and emerging evidence demonstrates aerobic exercise as an efficient therapeutical tool in the management of IR and IR-related metabolic disease. Interleukin-4 (IL-4), an important anti-inflammatory cytokine, was recently proved to be involved in regulation of IR, yet the effect of IL-4 on exercise-induced insulin sensitivity and underlying mechanism was less investigated. In this study, using a mouse model of swimming exercise training (60 min/day, 5 days/week for 8 weeks), we found that long-term swimming exercise promoted insulin sensitivity compared with sedentary groups as indexed by the homeostasis model assessment of insulin resistance (HOMA-IR), glucose and insulin tolerance test. Accompanying with increased insulin sensitivity, swimming exercise increased serum IL-4 levels as well as insulin receptor substrate 1 (IRS-1) and protein kinase B (Akt) phosphorylation. Mechanistically, IL-4 treatment increased insulin-stimulated glucose uptake and Akt phosphorylation in skeletal muscle C2C12 cells, and inhibition of IL-4 signaling via ruxolitinib, a Janus kinase (JAK) inhibitor, attenuated IL-4-induced insulin sensitivity. Taken together, our results demonstrated IL-4 as a novel exercise factor contributing to exercise-induced insulin sensitivity, providing a potential therapeutical target of IR and related metabolic disease.

7.
J Biomech ; 102: 109659, 2020 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-32070482

RESUMO

The study investigated the potential for obtaining more accurate spine joint reaction force (JRF) estimates from musculoskeletal models by incorporating dynamic stereo X-ray imaging (DSX)-based in vivo lumbar vertebral rotational and translational kinematics compared to generic, rhythm (RHY)-based kinematics, while also observing the influence of accompanying inputs: intervertebral segment stiffness and neutral state. A full-body OpenSim® musculoskeletal model, constructed by combining existing lower- and upper-body models, was driven based on one volunteer's (female; age 25; 60.8 kg; 176 cm) anthropometrics and kinematics from a series of upright standing and straight-legged dynamic lifting tasks. The lumbar spine portion was modified in a step-wise manner to observe effects of: (1) RHY vs. DSX lumbar kinematics; (2) No disc (bushing) stiffness (NBS); generic, linear bushing stiffness (LBS); subject-specific nonlinear bushing stiffness (NLBS); (3) Upright standing (UP) vs. Supine (SUP) neutral state; (4) Weight lifted: 4.5 kg vs. 13.6 kg. L4L5 JRF from 24 model variations based on combinations of aforementioned parameters were compared. Rhythm-based kinematics without translational components tends to over-predict JRF (31% and 39% for compression and shear, respectively) compared to DSX-based kinematics. Additionally, differences due to accompanying passive stiffness and neutral state choice combinations were even larger (>50%), indicating heightened demand on the quality of these accompanying inputs. The study not only highlights model sensitivity to choices made regarding the three primary inputs-kinematics, passive stiffness and neutral state- separately, but also how interactions between these choices can result in significant variability in joint loading estimates.

8.
Int J Biol Macromol ; 149: 1252-1261, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32035958

RESUMO

The aim of this study is to investigate whether Flammuliana Velutipes Polysaccharide (FVP) could aid in the prevention of colitis. Effect of FVP on colitis was evaluated using dextran sulfate sodium (DSS)-induced colitis in rats. Influence of FVP on the expression of inflammation related biomarkers and signal pathway element of TLR4\NF-κB were assessed. The composition and taxonomy of colonic microbiota were analyzed by 16S rDNA high throughput sequencing, and the concentrations of caecal short fatty chain acids were assessed by chromatography-mass spectrometry. Our results showed that FVP treatment could regulate the colonic microbial dysbiosis and promote the levels of caecal short fatty chain acids, leading to down-regulation of TLR4\NF-κB signal pathway, which finally ameliorate the colitis. Thus, the present study is the first attempt to elucidate the effect of FVP on colitis and support the potential application of FVP as a functional food ingredient or preventive drugs for colitis.

9.
Artigo em Inglês | MEDLINE | ID: mdl-32017343

RESUMO

A hybrid solid/liquid electrolyte with superior security facilitates the implementation of high-energy-density storage devices, but it suffers from inferior chemical compatibility with cathodes. Herein, an optimal lithium difluoro(oxalato)borate salt was introduced to build in situ an amorphous cathode electrolyte interphase (CEI) between Ni-rich cathodes and hybrid electrolyte. The CEI preserves the surface structure with high compatibility, leading to enhanced interfacial stability. Meanwhile, the space-charge layer can be prominently mitigated at the solid/solid interface via harmonized chemical potentials, acquiring promoted interfacial dynamics as revealed by COMSOL simulation. Consequently, the amorphous CEI integrates the bifunctionality to provide an excellent cycling stability, high Coulombic efficiency, and favorable rate capability in high-voltage Li-metal batteries, innovating the design philosophy of functional CEI strategy for future high-energy-density batteries.

10.
J Nanosci Nanotechnol ; 20(7): 4143-4151, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31968432

RESUMO

The current investigation reports the structural and biological evaluation of silver nanoparticles (AgNPs) biosynthesized from the pericarp extract of Cucumis melo L. (muskmelon). The AgNPs were characterized by ultraviolet-visible (UV-Vis) spectrophotometry, XRD (X-ray diffraction), SEM (scanning electron microscopy) and EDAX (energy-dispersive X-ray spectroscopy). The XRD analysis showed that biosynthesized AgNPs were having FCC (face centered cubic) crystalline structures. Further, the SEM and EDAX showed spherically shaped AgNPs having an average size of 25 nm. The AgNPs effectively inhibited the growth of Bacillus subtilis and Escherichia coli. Moreover, the cytotoxic assay of AgNPs revealed effective cytotoxicity against different cancer cells, such as HeLa, HCT-116, PC-3 and Jurkat in a dose reliant way. The cell viability was noticed to range from 50% to 60% with IC50 values ranging from 150 µg/mL to 224 µg/mL. The lower cell viability indicates the toxic effects of biosynthesized AgNPs against these malignant cells. Thus, the current study shows that these biosynthesized AgNPs could be utilized in various medical applications in near future.

12.
Protein Expr Purif ; 167: 105529, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31698035

RESUMO

During recombinant production of asymmetric IgG-like bispecific antibodies (bsAbs), various by-products are often observed due to unbalanced chain expression and incorrect chain pairing. Among them, half antibody and homodimer are found with high frequency. In this work, with a case study we demonstrated that Capto MMC ImpRes mixed-mode chromatography can effectively remove these two by-products as well as antibody aggregates under optimized conditions. This makes MMC ImpRes a powerful tool for bsAb purification.

13.
Environ Sci Technol ; 54(2): 1177-1185, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31829572

RESUMO

Flow-electrode electrochemical desalination (FEED) processes (e.g., flow-electrode capacitive deionization), which use flowable carbon particles as the electrodes, have attracted increasing attention, holding the promise for continuous desalination and high desalting efficiency. While it is generally believed that carbon particles with abundant microporous and large specific capacitances (e.g., activated carbon, AC) should be ideal candidates for FEED electrodes, we provide evidence to the contrary, showing that highly conductive electrodes with low specific surface area can outperform microporous AC-based electrodes. This study revealed that FEED using solely high surface area AC particles (∼2000 m2 g-1, specific capacitance of ∼44 F g-1, average salt adsorption rate of ∼0.15 µmol cm-2 min-1) was vastly outperformed by electrodes based solely on low-surface area carbon black (CB, ∼70 m2 g-1, ∼0.5 F g-1, ∼0.75 µmol cm-2 min-1). Electrochemical impedance spectroscopy results suggest that the electrode formed by CB particles led to more effective electronic charge percolation, likely contributing to the improved desalination performance. In addition, we propose and demonstrate a novel operation mode, termed single cycle (SC), which greatly simplified the FEED cell configuration and enabled simultaneous charging and discharging. Using SC mode with CB flow electrodes delivered an increased average salt removal rate relative to the more traditional short-circuited closed cycle (SCC) mode, achieving up to 1.13 µmol cm-2 min-1. Further investigations demonstrate that up to 50% of energy input would be avoided when using CB flow electrodes operated under SC mode as compared to that of AC flow electrodes operated under SCC mode. In summary, the FEED process presented in this study provided an innovative and promising approach toward high-efficient and low-cost brackish water desalination.

14.
Lab Chip ; 20(3): 496-504, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-31840725

RESUMO

This study presented a flexible liquid metal-based microdroplet capacitive sensor that would simply and accurately measure the speed and length of droplets flowing in microchannels. A pair of coplanar U-shaped electrodes was used to form a capacitance through droplet microchannels. Liquid metal was injected into polydimethylsiloxane (PDMS) channels to form the U-shaped electrodes. The sensor would generate a multi-plateau capacitance waveform as a droplet passes through the sensing area, and each plateau period corresponds to the droplet position in the sensing area. The droplet speed and length would be directly calculated from the multi-plateau capacitance waveform. The errors for the capacitive result relative to the real value were <7.2% for length and <2.8% for speed. Moreover, the sensor still maintained excellent performance for droplet length and speed measurement even though the microfluidic chip was bent to 96°. We have demonstrated that the capacitive sensor would be used for sweat rate monitoring.

15.
J Cell Physiol ; 235(3): 2761-2775, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31531884

RESUMO

Pancreatic cancer (PC) is one of the most deadly digestive cancers world-wide, with a dismal five-year survival rate of <8%. Upregulation of transmembrane protein 158 (TMEM158) is known to facilitate the progression of several carcinomas. However, little is known concerning the potential roles of TMEM158 in PC. Herein, we first found that TMEM158 was significantly upregulated in PC samples as well as PC cell lines. The overexpression of TMEM158 was significantly correlated with advanced clinicopathologic features (including tumor size, TNM stage, and blood vessel invasion) and poorer prognosis of patients with PC in clinic. Evidenced based on a series of loss- and gain-of-function assays uncovered that TMEM158 enhanced PC cell proliferation, migration, and invasion by stimulating the progression of cell cycle, epithelial-mesenchymal transition, and MMP-2/9 production. Furthermore, mechanism-related investigations disclosed that activation of TGFß1 and PI3K/AKT signal might be responsible for TMEM158-triggered PC aggressiveness. Collectively, TMEM158 was upregulated in PC and promoted PC cell proliferation, migration, and invasion through the activation of TGFß1 and PI3K/AKT signaling pathways, highlighting its potential as a tumor promoter and a therapeutic target for PC.

16.
J Mol Graph Model ; 96: 107509, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31881467

RESUMO

The anisotropy in elasticity, mechanical properties and electronic properties of CaM2Al20 (M = V, Nb, Cr, Ti, Mo and Ta) compounds were investigated using the first-principle calculations. These ternary compounds are structurally stable according to the obtained phonon frequencies and formation enthalpy. The results of elastic modulus, hardness and elastic constants explain that CaM2Al20 intermetallics have higher hardness and better resistance to deformation change than pure aluminum. Poisson's ratio and the values of B/G confirm that CaTi2Al20, CaV2Al20, CaCr2Al20, CaNb2Al20 and CaTa2Al20 are brittle materials, but CaMo2Al20 is ductile material. The 3D surfaces of Young's modulus and anisotropic constants confirm that CaMo2Al20 and CaTi2Al20 have the larger anisotropy than other four compounds. What's more, the density of states and charge density differences of CaM2Al20 compounds explain the mechanism of the structural stability and mechanical properties.

17.
Colloids Surf B Biointerfaces ; 186: 110727, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31862562

RESUMO

Although silver nanoparticles are considered as promising antibacterial agents because of their antibacterial activity, the acute cytotoxicity of Ag+ released from Ag nanoparticles restricts their potential practical applications. Herein, porous Ag@Au nanoplates, which could balance the Ag+ release and the toxicity of Ag naoparticles, were fabricated by stepwise seed-mediated growth and oxidation. Laser irradiation further boosted their antimicrobial activity, and significantly accelerated the curing rate of wound. Comparing with Ag nanoplates, the irradiated porous Ag@Au nanoplates showed the similar antibiotic ability against S. aureus strains and lower cytotoxicity in vitro. When the porous Ag@Au nanoplates were applied to treat S. aureus-infected wound, they had the best curing effect. Thus, these porous Ag@Au nanoplates could act as promising antibacterial agents for wound healing applications.

18.
Mol Ther Nucleic Acids ; 19: 109-123, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31837602

RESUMO

Long non-coding RNAs (lncRNAs) play critical roles in tumorigenesis and tumor progression. However, the biological function of most lncRNAs remains unknown in human gastric cancer. This study here aims to explore the unknown function of lncRNA MAGI2-AS3 in gastric cancer. First, bioinformatics analysis showed that lncRNA MAGI2-AS3 was overexpressed in gastric cancer tissues, and the overexpression of MAGI2-AS3 has been shown to be associated with poor prognosis in all three independent gastric cancer cohorts (The Cancer Genome Atlas stomach cancer [TCGA_STAD], GEO: GSE62254 and GSE15459). The multivariate analysis indicated that lncRNA MAGI2-AS3 was an independent prognostic factor for both overall survival and disease-free survival of gastric cancer patients. Moreover, MAGI2-AS3 was identified to be an epithelial-mesenchymal transition (EMT)-related lncRNA and was highly co-expressed with ZEB1/2 in both gastric cancer tissues and normal stomach tissues. Loss-of-function and gain-of-function studies showed that lncRNA MAGI2-AS3 could positively regulate ZEB1 expression and the process of cell migration and invasion in gastric cancer. Subcellular location assay showed that lncRNA MAGI2-AS3 was mainly located in the cytoplasm of gastric cancer cells. Bioinformatics analysis and functional experiments revealed that lncRNA MAGI2-AS3 was negatively correlated with miR-141/200a expression and negatively regulated miR-141/200a-3p expression in gastric cancer. Therefore, we speculate that lncRNA MAGI2-AS3 promotes tumor progression through sponging miR-141/200a and maintaining overexpression of ZEB1 in gastric cancer. Nevertheless, we identified that BRD4 is a transcriptional regulator of lncRNA MAGI2-AS3 in gastric cancer. Additionally, our findings highlight that lncRNA MAGI2-AS3 is an ideal biomarker and could be a potential therapeutic target for gastric cancer.

19.
Appl Opt ; 58(27): 7582-7587, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31674411

RESUMO

In this paper, an in-line Mach-Zehnder interferometer embedded in a fiber Bragg grating (FBG) is fabricated by a tiny offset-core splicing technique and inserted into a fiber ring laser to effectively improve the detection limit and discrimination of sensing. Through fine power adjustment, the stable operation of dual-wavelength lasing is completed in a single FBG for the first time to our knowledge, and simultaneous measurement of refractive index (RI) and ambient temperature is achieved with high discrimination due to the RI immunity of the FBG. The experimental results indicate that the sensitivities of RI and temperature are -30.57 nm/RIU and 131.1 pm/°C, respectively, with very low intensity drift. Furthermore, the over 20 times improvement of the RI detection limit is obtained owing to the large extinction ratio (>30 dB) and small linewidth (≤0.13 nm).

20.
Nat Commun ; 10(1): 4930, 2019 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-31666514

RESUMO

Metallic lithium affords the highest theoretical capacity and lowest electrochemical potential and is viewed as a leading contender as an anode for high-energy-density rechargeable batteries. However, the poor wettability of molten lithium does not allow it to spread across the surface of lithiophobic substrates, hindering the production and application of this anode. Here we report a general chemical strategy to overcome this dilemma by reacting molten lithium with functional organic coatings or elemental additives. The Gibbs formation energy and newly formed chemical bonds are found to be the governing factor for the wetting behavior. As a result of the improved wettability, a series of ultrathin lithium of 10-20 µm thick is obtained together with impressive electrochemical performance in lithium metal batteries. These findings provide an overall guide for tuning the wettability of molten lithium and offer an affordable strategy for the large-scale production of ultrathin lithium, and could be further extended to other alkali metals, such as sodium and potassium.

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