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2.
Opt Lett ; 44(21): 5262-5265, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31674983

RESUMO

Polarization modulation plays a key role in polarization-encoding quantum key distribution (QKD). Here, we report a new, to the best of our knowledge, polarization modulation scheme based on an inherently stable Sagnac interferometer. The presented scheme is free of polarization mode dispersion and calibration as well as insensitive to environmental influences. Successful experiments at a repetition frequency of 1.25 GHz have been conducted to demonstrate the feasibility and stability of the scheme. The measured average quantum bit-error rate of the four polarization states is as low as 0.27% for 80 consecutive minutes without any adjustment. This high-speed intrinsically stable polarization modulation can be widely applied to many polarization-encoding QKD systems, such as BB84, MDI, etc.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31670455

RESUMO

Photocatalytic overall water splitting has been recognized as a promising approach to convert solar energy into hydrogen. However, most of the photocatalysts suffer from low efficiencies mainly due to the poor charge separation property. Herein, taking a model semiconductor gallium nitride (GaN) as an example, we uncovered that photogenerated electrons and holes can be spatially separated to the nonpolar and polar surfaces of GaN nanorod arrays, which is presumably ascribed to the different surface band bending induced by the surface polarity. The photogenerated charge separation efficiency of GaN can be enhanced significantly from ~8% to more than 80% via co-exposing polar and nonpolar surfaces. Furthermore, spatially assembling of reduction and oxidation cocatalysts selectively on the nonpolar and polar surfaces remarkably boosts photocatalytic overall water splitting, with the quantum efficiency increased from 0.9% for the film photocatalyst to 6.9% for the nanorod arrays photocatalyst.

4.
J Cell Mol Med ; 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31571401

RESUMO

Osteoarthritis (OA) is a degenerative joint disease that commonly occurs in the elderly. This study focused on apoptosis and explored the modulating effects of long non-coding (lncRNAs) prostate androgen-regulated transcript-1 (PART-1) on chondrocytes apoptosis. In the present study, the PART-1 expression level was down-regulated in the OA cartilages. Silence of PART-1 decreased the cell viability and promoted chondrocytes apoptosis. Overexpression of PART-1 could reverse the effects induced by interleukin 1ß (IL-1ß) stimulation, thus slowing down the apoptosis rate. MiR-590-3p was found to be the potential target, and RNA immunoprecipitation and luciferase activity assay confirmed the binding between PART-1 and miR-590-3p. Moreover, miR-590-3p was down-regulated by PART-1 and was negatively associated with PART-1. Transforming growth factor-beta receptor type 2 (TGFBR2) was positively associated with PART-1. Down-regulation of PART-1 decreased cell viability and induced cell apoptosis, which was partially reversed by miR-590-3p silence or TGFBR2 overexpression; while overexpression of PART-1 increased the cell viability and decreased the caspase 3 activity and apoptotic rates, and the effects were partially attenuated by miR-590-3p overexpression or silence of TGFBR2 in IL-1ß-stimulated chondrocytes. Knock-down of PART-1 down-regulated both Smad3 and p-Smad3 protein levels, which was reversed by miR-590-3p inhibition or TGFBR2 overexpression. Smad3 expression level was lower in the OA group than that in the normal group and was positively associated with the PART-1 expression level. Collectively, the study revealed that lncRNA PART-1 regulates the apoptosis of chondrocytes in OA by acting as a sponge for miR-590-3p, which subsequently regulates TGFBR2/Smad3 signalling.

5.
J Asian Nat Prod Res ; : 1-6, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31573332

RESUMO

Two new compounds, daedatrin K (1) and 2-hydroxy-1-(5-(hydroxymethyl)furan-2-yl)propan-1-one (2), were isolated from cultures of the basidiomycetes Daedaleopsis tricolor. The new structures were elucidated on the basis of extensive spectroscopic methods. At the same time, two compounds were tested for their cytotoxicities against five human cancer cell lines.

6.
Oncol Rep ; 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31578585

RESUMO

Platinum­containing doublet chemotherapy is the cornerstone of lung cancer treatment; however, cisplatin resistance is a major obstacle in the treatment of lung cancer. However, the mechanism underlying this resistance has not been fully elucidated. Previous studies have shown that serum apurinic/apyrimidinic endonuclease 1 (APE1) levels in patients with NSCLC are inversely associated with progression­free survival after platinum­containing doublet chemotherapy, and can serve as a biomarker for predicting disease prognosis and treatment efficacy. The present study was designed to investigate the role played by APE1 in the resistance of lung cancer to cisplatin. The levels of mitochondrial apurinic endonuclease 1 (m­APE1) and total APE1 (t­APE1) protein in a cisplatin­resistant A549 cell line (A549/DDP) and cisplatin­sensitive A549 cells were analyzed by western blotting. Mitochondrial membrane potential was detected by using the JC­1 staining method. The cisplatin­resistance of APE1­overexpressing A549 cells and APE1­silenced A549/DDP cells was assessed by cell apoptosis and colony formation assays. The results revealed that cisplatin­resistant A549 cells contained high levels of APE1, and exhibited elevated levels of autophagy. The levels of m­APE1 and t­APE1 protein were increased in the A549/DDP cells when compared with these levels in the A549 cells. Overexpression of APE1 and Mia40 enhanced the cisplatin resistance and autophagy of the A549 cells. APE1 knockdown restored the cisplatin sensitivity and reduced the levels of LC3II and Parkin in the A549/DDP cells, but promoted the release of cytochrome c. Furthermore, Parkin silencing or treatment with 3­methyladenine (3­MA, an autophagy inhibitor) promoted the apoptosis of APE1­overexpressing A549 cells, indicating that Parkin­mediated mitophagy plays an important role in the APE1­induced cisplatin resistance of A549 cells. In conclusion, APE1 promotes the cisplatin resistance of lung cancer cells by inducing Parkin­mediated mitophagy.

7.
Pediatr Surg Int ; 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31586234

RESUMO

PURPOSE: We investigated the anorectal musclulature in normal children and anorectal malformations (ARM) to evaluate its role in bowel control mechanism. METHODS: Pelves of 50 neonates died of ARM-unrelated diseases and 16 patients with anorectal malformations (8 high, 5 intermediate, and 3 low ARMs) were dissected and analyzed. RESULTS: Normal anorectal musculature was divided into three muscular tubes: the internal sphincter tube (IAST), longitudinal muscle tube (LMT) and transverse muscle tube (TMT). The LMT came from the outer longitudinal smooth muscle fiber of the rectum and the striated muscle fiber of the levator ani, and the TMT composed of the puborectalis and the external anal sphincter. However, in ARM, the IAST was absent and the LMT, the center of the sphincter muscle complex, was only from the levator ani and could be divided into the pelvic portion and the perineal portion. The former, from the upper rim of the puborectalis to the bulbar urethral, became narrowed and dislocated anteriorly near to the posterior urethra in high ARM and rectal pouch in intermediate ARM. The latter, below the bulbar urethra to the anal dimple, was fused to a column both in high and intermediate ARM. The columnar perineal LMT run downwards and then split, penetrated the superficial part of EAS and terminated at the deep aspect of the skin, to form the anal dimple, which represents the center of the perineal LMT from the perineal aspect. The length of the LMT was longer in high and intermediate ARM than the normal neonate. The columnar perineal LMT and narrowed pelvic LMT could be possibly identified by laparoscopic and perineal approaches retrospectively and widened to allow the passage of the rectum through. CONCLUSIONS: The anorectal musculature in ARM is composed of agenesic LMT and TMT and the narrowed LMT gives anatomical evidence of the center, where the neorectum should pull through.

8.
Stem Cells ; 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31574189

RESUMO

Mitochondrial phosphoenolpyruvate carboxykinase (PCK2) is a rate-limiting enzyme that plays critical roles in multiple physiological processes. The decompensation of PCK2 leads to various energy metabolic disorders. However, little is known regarding the effects of PCK2 on osteogenesis by human mesenchymal stem cells (hMSCs). Here, we report a novel function of PCK2 as a positive regulator of MSCs osteogenic differentiation. In addition to its well-known role in anabolism, we demonstrate that PCK2 regulates autophagy. PCK2 deficiency significantly suppressed autophagy, leading to the impairment of osteogenic capacity of MSCs. On the other hand, autophagy was promoted by PCK2 overexpression; this was accompanied by increased osteogenic differentiation of MSCs. Moreover, PCK2 regulated osteogenic differentiation of MSCs via AMP-activated protein kinase (AMPK)/unc-51 like autophagy activating kinase 1(ULK1)-dependent autophagy. Collectively, our present study unveiled a novel role for PCK2 in integrating autophagy and bone formation, providing a potential target for stem cell-based bone tissue engineering that may lead to improved therapies for metabolic bone diseases. Stem Cells 2019.

9.
J Phys Chem Lett ; : 6536-6544, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31589459

RESUMO

The advent of ultrashort soft X-ray pulse sources permits the use of established gas-phase spectroscopy methods to investigate ultrafast photochemistry in isolated molecules with element and site specificity. In the present study, we simulate excited-state wavepacket dynamics of a prototypical process, the ultrafast photodissociation of methyl iodide. Using the simulation, we calculate time-dependent excited-state carbon edge photoelectron and Auger electron spectra. We observe distinct signatures in both types of spectra and show their direct connection to C-I bond dissociation and charge rearrangement processes in the molecule. We demonstrate at the CH3I molecule that the observed signatures allow us to map the time-dependent dynamics of ultrafast photoinduced bond breaking with unprecedented detail.

10.
Artigo em Inglês | MEDLINE | ID: mdl-31606406

RESUMO

The application of Water Safety Plans (WSPs) in China varies throughout the country. Although pilot WSP projects in China were initiated shortly after WSP was introduced by the World Health Organization (WHO) in 2004, they have yet to be used for water supply facilities at a large scale. To better understand the evolution of WSP application in China, a systematic review was conducted to identify all published WSP related studies in China. Eighteen studies, which included 311 water systems, were included in the final analysis. Risk matrix, water supply risk factors, and other data were extracted and analyzed. Text mining methods were also used to better understand risks that can be addressed by WSPs (both potential and actual risks). This study revealed a number of noteworthy differences between and among urban and rural water systems in China. The primary risks associated with most urban water supply systems tended to be related to mechanical failure/s in the water treatment process. Rural water supply systems appear to suffer from similar problems, but insufficient overall management capacity was more prevalent in rural systems. Overall, the evidence suggests that, to date, the use of WSPs in China has been primarily limited to pilot studies, and full implementation of WSPs in China appears to still be in the early stages. The paper closes with a summary of the key obstacles identified as well as a discussion of policies and technical options which could increase the use of WSPs in both urban and rural China. Among other recommendations, the data indicate that there is strong need for the development and implementation of a simplified WSP approach designed specifically for small rural systems in China.

11.
J Sci Food Agric ; 2019 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-31587285

RESUMO

BACKGROUND: Phosphorylation is one of the most important post-translational modifications. Currently, many postmortem protein phosphorylations in muscle have been related to meat quality such as tenderness, and color stability. However, the effects of various storage temperatures (25°C, 15°C, 4°C and -1.5°C) on the phosphorylation level of protein are poorly understood. Changes in the protein phosphorylation levels in postmortem ovine muscle at various storage temperatures were determined in this study. RESULTS: The obtained data showed that pH decline rate was significantly inhibited at -1.5°C from 12 h to 7 d postmortem (P < 0.05). The ATP consumption rate was higher at 25°C than that at other three temperatures (P < 0.05). Analysis of the temperature, pH and ATP content revealed that the ATP content was related to the phosphorylation levels of individual protein bands. Phosphorylated myofibrillar and sarcoplasmic proteins, such as myosin binding protein C, troponin T3, myosin light chain 1, glucose-6-phosphate isomerase and pyruvate kinase, were mainly involved in glycolysis and muscle contraction. CONCLUSION: The global and specific protein phosphorylation levels can be influenced by the postmortem storage temperature of muscle. Phosphorylation of proteins was correlated with glycolysis and muscle contraction. Certain phosphorylated proteins, such as heat shock proteins, require further study to clarify their effects on meat traits. This article is protected by copyright. All rights reserved.

12.
Arterioscler Thromb Vasc Biol ; : ATVBAHA119312976, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31619063

RESUMO

OBJECTIVE: Vascular endothelial cells (ECs) normally maintain vascular homeostasis and are regulated by proinflammatory cytokines and reactive oxygen species. A human genome-wide association study identified that AIP1 (ASK1-interacting protein-1; also identified as DAB2IP) gene variants confer susceptibility to cardiovascular disease, but the underlying mechanism is unknown. Approach and Results: We detected a normal AIP1 form (named AIP1A) in the healthy aorta, but a shorter form of AIP1 (named AIP1B) was found in diseased aortae that contained atherosclerotic plaques and graft arteriosclerosis. AIP1B transcription in resting ECs was suppressed through epigenetic inhibition by RIF1 (Rap1-interacting factor 1)/H3K9 (histone H3 lysine 9) methyltransferase-mediated H3K9 trimethylation, and this inhibition was released by proinflammatory cytokines. AIP1A, but not AIP1B, was downregulated by proteolytic degradation through a Smurf1 (SMAD ubiquitylation regulatory factor 1)-dependent pathway in ECs under inflammation. Therefore, AIP1B was the major form present during inflammatory conditions. AIP1B, which lacks the N-terminal pleckstrin homology domain of AIP1A, localized to the mitochondria and augmented TNF (tumor necrosis factor)-induced mitochondrial reactive oxygen species generation and EC activation. AIP1B-ECTG (EC-specific AIP1B transgenic) mice exhibited augmented reactive oxygen species production, EC activation, and neointima formation in vascular remodeling models. CONCLUSIONS: Our current study suggests that a shift from anti-inflammatory AIP1A to proinflammatory AIP1B during chronic inflammation plays a key role in inflammatory vascular diseases.

13.
Cell Prolif ; : e12704, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31621141

RESUMO

Intervertebral disc degeneration (IDD) is a common cause of low back pain, which inflicts more global disability than any other condition. Although IDD was deemed to be a natural process that comes with ageing, a growing body of evidence suggested that both genetic and environmental factors could modify the development of IDD. In this connection, aberrant function of nucleus pulposus cells has been implicated in IDD pathogenesis. Circular RNAs are a novel class of endogenous non-coding RNAs that play crucial regulatory roles in diverse cellular processes. Recently, deregulation of circRNAs in nucleus pulposus cells was found to functionally participate in IDD development. In this review, we summarize the current knowledge regarding the deregulation of circRNAs in IDD in relation to their actions on nucleus pulposus cell functions, including cell proliferation, apoptosis and extracellular matrix synthesis/degradation. The potential clinical utilities of circRNAs as therapeutic targets for the management of IDD are also discussed.

14.
Int J Infect Dis ; 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31580939

RESUMO

BACKGROUND: Few data about healthcare-associated infection (HAI) is available from the developing world, thus we conducted a point prevalence survey (PPS) to determine the prevalence of HAI and antimicrobial use (AMU) in Guangdong province, China. METHODS: A standardized methodology for PPS on HAIs and AMU has been developed by Chinese Nosocomial Infection Control and Quality Improvement Centre. Prevalence of HAI, AMU and baseline hospital-level variables were collected in 189 hospitals from June 2017 to May 2018. RESULTS: Of 5,868,147 patients, 72,976 had one or more HAIs (1.24%) with distinct 82,700 HAIs. The prevalence of device-associated infections, including ventilator-associated pneumonia, catheter-associated urinary tract infection and central-line-associated bloodstream infection were 7.92, 2.06 and 0.63 per 1,000 catheter days, respectively. 10,591(0.18%) HAIs caused by MDROs were identified. Carbapenem nonsusceptibility rates were highest in Acinetobacter species (53.86%) and P. aeruginosa (21.60%). 46.22% (2,712,258/5,868,147) of inpatients were receiving at least one antimicrobial during this survey. CONCLUSIONS: Our survey indicated the relatively lower prevalence of HAI but higher antimicrobial using in Guangdong province compared with other mid-low income and high-income countries. Further studies are warranted to elucidate which HAI-related indicators are the best measures of HAI performance and thus allow improvements leading to better patient outcomes.

15.
Dig Dis Sci ; 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31584135

RESUMO

BACKGROUND: A recent study reported a novel long non-coding RNA (lncRNA) E2F-mediated cell proliferation enhancing lncRNA (EPEL, human chromosome 4, intergenic region) plays an oncogenic role in lung cancer. AIMS: We aimed to investigate the role of lncRNA EPEL in gastric cancer. METHODS: Gene expression was analyzed by RT-qPCR and western blot. Survival analysis was performed by comparing survival curves. Cell proliferation, migration, and invasion were analyzed by CCK-8 and Transwell assays. RESULTS: We found that lncRNA EPEL and Runt-related transcription factor 2 (RUNX2) were both upregulated in gastric cancer. EPEL and RUNX2 were positively correlated in tumor. Patients with high expression level of lncRNA EPEL showed poor survival. LncRNA EPEL and RUNX2 overexpression promoted, while lncRNA EPEL siRNA silencing inhibited the migration, proliferation, and invasion of gastric cancers. In addition, RUNX2 overexpression completely rescued the inhibited cancer cell migration, proliferation, and invasion caused by lncRNA EPEL siRNA silencing. Consistently, EPEL overexpression resulted in upregulated RUNX2 expression, while RUNX2 overexpression did not affect lncRNA EPEL expression. CONCLUSIONS: Therefore, lncRNA EPEL may regulate cancer cell behaviors and affect prognosis of gastric cancer by interacting with RUNX2.

16.
Environ Pollut ; 255(Pt 2): 113327, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31600703

RESUMO

Fish-associated antibiotic resistance genes (ARGs) have attracted increasing attention due to their potential risks to human beings via the food chain. However, data are scarce regarding the antibiotic resistance in fish themselves. Herein, the antibiotic resistance genes (ARGs) were assessed in the gut of four major Chinese freshwater carp (i.e., silver carp, grass carp, bighead carp, and crucian carp) from food retail markets. Results show that the abundances of target ARGs (e.g., tetA, tetO, tetQ, tetW, sulI, sulII, and blaTEM-1) and class 1 integrase (intI1) were in the range 9.4 × 10-6 - 1.6 × 10-1 and 6.7 × 10-5 - 5.2 × 10-2 gene copies per 16S rRNA gene, respectively. The sulI, sulII, and tetQ strongly correlated with silver and mercury resistance genes (e.g., silE and merR). The microbial taxa of fish gut could be partly separated among retail markets based on the PCA analysis. About 15.0% of the OTUs in fish gut were shared and 74.5% of the shared OTUs were identified as Acidobacteria, Bacteroidetes, Chloroflexi, Cyanobacteria, Firmicutes, and Proteobacteria. These phyla may constitute the core microbiota in the guts of the four Chinese freshwater carp. The possible ARG hosts were revealed based on the network analysis, and the presence of pathogen-associated resistant genera in fish gut highlights the need to fully understand their potential human health risks.

17.
Artigo em Inglês | MEDLINE | ID: mdl-31628532

RESUMO

Gold nanoparticles (AuNPs) attracted much attention owing to their distinguished characteristics and applications. In this study, rod-shaped AuNPs were biosynthesized using Pb2+-induced fungus Aspergillus sp. The synthesized AuNPs showed a UV-vis absorption peak at 534 nm. Scanning electron microscopy and transmission electron microscopy analyses showed that rod-shaped AuNPs were biosynthesized and attached on the mycelia surfaces. Energy-dispersive spectrometer analysis identified gold as the unique metallic composition of synthesized nanoparticles. X-ray powder diffraction analysis showed that the AuNPs were face-centered cubic crystalline structure. Furthermore, Fourier transform infrared spectroscopy analysis detected functional groups, including C = O, C-O-C, amine I and II which played active roles in AuNPs formation. In addition, the main shape of synthesized AuNPs changed from sphere to rod-shape with the increase of biomass and Pb2+ concentration. This study reports quite uniform rod-shaped AuNPs biosynthesized using Pb2+-induced fungus Aspergillus sp. WL-Au for the first time. This will provide a valid alternative for oriented biosynthesis of AuNPs.

18.
Int J Nurs Pract ; : e12776, 2019 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-31631496

RESUMO

BACKGROUND: Central line-associated blood stream infections are accompanied by increased mortality and health care costs. The application of different types of dressings in infection control has not been fully investigated to date. AIM: To assess the effects of two different dressing types on central line-associated bloodstream infections. METHODS: A randomized, nonblinded, controlled trial was conducted. Central lines were randomly allocated to intervention (chlorhexidine gluconate transparent dressing, n = 259) and control groups (standard dressing, n = 215). The central line-associated bloodstream infection rate was assessed. RESULTS: A statistically nonsignificant difference was noted in the overall central line-associated bloodstream infection rates between the two groups. The frequency of dressing changes in the patients with the chlorhexidine gluconate transparent dressing was significantly lower than that in the patients with a standard dressing. The predominant type of infectious microorganisms isolated from the central line-associated bloodstream infection episodes was Gram-negative bacteria (57.2%). Gram-positive bacteria and fungi were noted at lower percentages (28.5% and 14.3%, respectively). CONCLUSION: The use of a chlorhexidine gluconate transparent dressing does not decrease the central line-associated bloodstream infection rate, although it decreases the frequency of dressing changes so may save nursing time.

19.
Virus Res ; : 197790, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31655083

RESUMO

Apple stem grooving virus (ASGV) belongs to the genus Capillovirus within the family Betaflexiviridae. In this work, we described the construction of full-length infectious cDNA clones of ASGV isolate jilin-shaguo (JL-SG) using the Gibson Assembly approach (New England BioLabs). The isolate was previously detected in a Chinese pear-leaf crab apple (Malus asiatica Nakai.) in Baicheng, Jilin province, China. Two full-length cDNA clones of ASGV JL-SG were obtained, and they are identical to each other in sequence. The full-length cDNA clone was infectious on Chenopodium quinoa, Nicotiana glutinosa, and N. occidentalis 37B via agroinfiltration. Through sap inoculation, the infection was additionally spread to C. amaranticolor. N. benthamiana could not be infected, neither through agroinfiltration nor sap inoculation. In infected herbaceous plants, typical ASGV particles with morphology of flexuous filaments were observed by transmission electron microscope (TEM). Moreover, seeds of infected N. glutinosa and N. occidentalis 37B were collected and germinated, the seedlings were ASGV-free in RT-PCR test, suggesting ASGV JL-SG is not seed-transmissible in the tested Nicotiana species. In addition, the cDNA clone was agroinfiltrated into seedlings of Malus pumila cv. Fuji. The infection was symptomless, and can be spread to C. quinoa via sap inoculation, causing typical symptoms. ASGV JL-SG was also detected by RT-PCR in inoculated the infected Fuji plants, however, no virion was observed by TEM.

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