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1.
Chemosphere ; 238: 124645, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31472352

RESUMO

Bromophenols (BPs) are important organic compounds which have become dominant pollutants during these years. Our present study investigated the potential inhibition behaviour of BPs on the activity of one of the most important phase II drug-metabolizing enzymes (DMEs), UDP-glucuronosyltransferases (UGTs). Recombinant UDP-glucuronosyltransferases (UGTs)-catalyzed glucuronidation of 4-methylumbelliferone (4-MU) was utilized as the probe reaction. 100 µM of BPs was utilized as the inhibition screening concentrations, and the complete inhibition profile of UGT isoforms by BPs was obtained. UGT1A7 was the most vulnerable UGT isoform towards BPs. Some structure-activity relationship for the inhibition of UGTs by BPs was found, and this relationship can be furtherly explained by the hydrophobic contacts of BPs with the activity cavity of UGTs using in silico docking method. The inhibition kinetics determination showed that the inhibition kinetic parameter Ki value was calculated to be 2.85, 3.99 and 31.00 µM for the inhibition of UGT1A3, UGT1A7, and UGT2B7 by representative BPs, 2,4,6-TBP. Combined with in vivo exposure concentration of 2,4,6-TBP, in vitro-in vivo extrapolation (IVIVE) was employed to demonstrate the moderate possibility for the inhibition of UGT1A3 and UGT1A7 by 2,4,6-TBP. In conclusion, our study gave the full description towards the inhibition of BPs towards UGT isoforms, which will provide a new perspective for elucidating the toxicity mechanism of bromophenols (BPs).

2.
Chemosphere ; 240: 124945, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31726594

RESUMO

In this study, the effect of high concentration of Mn2+ on the aerobic granular sludge (AGS) systems for aniline wastewater treatment was systematically investigated in terms of AGS formation and pollutant removal efficiency. Two parallel sequencing batch reactors were operated to treat the aniline-rich wastewater with and without 20 mg L-1 of Mn2+. In the presence of Mn2+, the time to granulation was prolonged from 23 d to 30 d due to the toxicity of the high concentration of Mn2+. However, the mature granules with Mn2+ produced more protein and polysaccharides, and had a larger size (870 µm) than that without Mn2+ (740 µm). The extracellular polymeric substances of the granules in the two reactors had similar protein compositions, but some functional groups increased with Mn2+. The reactors showed high overall removal efficiency of chemical oxygen demand, NH4+-N, and total nitrogen with average concentrations below 40, 1.0, and 19 mg L-1, respectively, in the effluents. In one typical operating cycle, however, Mn2+ retarded nitrification and the degradation of aniline, while promoted denitrification. The microbial community analysis revealed that the growth of Terrisporobacter, Pseudomonas, and many other bacteria responsible for aniline degradation was inhibited by Mn2+, and so were the strains involved in nitrification. In contrast, Mn2+ facilitated the growth of denitrifying bacteria.

3.
AJR Am J Roentgenol ; : 1-13, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31670595

RESUMO

OBJECTIVE. The purpose of this study was to establish procedure-specific air kerma-area product (KAP) and effective dose for a large number of fluoroscopically guided interventional (FGI) procedures. MATERIALS AND METHODS. This retrospective study collected dose data for consecutive adult cases from 12 examination rooms between May 2016 and October 2018. A total of 24,911 cases (50.9% men) were categorized by procedure. Effective dose was calculated using KAP and procedure-specific KAP to effective dose conversion coefficients, mostly from National Council on Radiation Protection and Measurements (NCRP) Report 160. Data analysis was conducted with statistical software to determine mean value and five percentiles (10th, 25th, 50th, 75th, 95th). RESULTS. KAP and effective dose were presented for 101 procedures; a national benchmark is not available from NCRP Reports 168 and 172 for the KAP value of 89 procedures and for the effective dose of all 101 procedures. Twelve procedures that comprised at least 50% of patient cases had median KAP values less than 3.26 Gy · cm2 and a median effective dose of less than 0.70 mSv. However, some infrequent procedures might be associated with a higher dose. The 95th percentile of KAP was greater than or equal to 500 Gy · cm2 for 16 procedures and 985 Gy · cm2 for portography; for effective dose it was greater than or equal to 100 mSv for 21 procedures and 256 mSv for portography. CONCLUSION. The values for KAP and effective dose provided in this article can aid in design and review of clinical research protocols and dose management programs and in assessing compliance with the Joint Commission's standards for organizations providing fluoroscopy services in the absence of national benchmarks for more than 89 procedures.

4.
World J Gastroenterol ; 25(40): 6107-6115, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31686766

RESUMO

BACKGROUND: Endoscopic retrograde cholangiopancreatography (ERCP) has been widely used in pediatric patients with cholangiopancreatic diseases. AIM: To evaluate the efficacy, safety, and long-term follow-up results of ERCP in symptomatic pancreaticobiliary maljunction (PBM). METHODS: A multicenter, retrospective study was conducted on 75 pediatric patients who were diagnosed with PBM and underwent therapeutic ERCP at three endoscopy centers between January 2008 and March 2019. They were divided into four PBM groups based on the fluoroscopy in ERCP. Their clinical characteristics, specific ERCP procedures, adverse events, and long-term follow-up results were retrospectively reviewed. RESULTS: Totally, 112 ERCPs were performed on the 75 children with symptomatic PBM. Clinical manifestations included abdominal pain (62/75, 82.7%), vomiting (35/75, 46.7%), acholic stool (4/75, 5.3%), fever (3/75, 4.0%), acute pancreatitis (47/75, 62.7%), hyperbilirubinemia (13/75, 17.3%), and elevated liver enzymes (22/75, 29.3%). ERCP interventions included endoscopic sphincterotomy, endoscopic retrograde biliary or pancreatic drainage, stone extraction, etc. Procedure-related complications were observed in 12 patients and included post-ERCP pancreatitis (9/75, 12.0%), gastrointestinal bleeding (1/75, 1.3%), and infection (2/75, 2.7%). During a mean follow-up period of 46 mo (range: 2 to 134 mo), ERCP therapy alleviated the biliary obstruction and reduced the incidence of pancreatitis. The overall effective rate of ERCP therapy was 82.4%; seven patients (9.3%) were lost to follow-up, eight (11.8%) re-experienced pancreatitis, and eleven (16.2%) underwent radical surgery, known as prophylactic excision of the extrahepatic bile duct and hepaticojejunostomy. CONCLUSION: ERCP is a safe and effective treatment option to relieve biliary or pancreatic obstruction in symptomatic PBM, with the characteristics of minor trauma, fewer complications, and repeatability.

5.
Phys Rev Lett ; 123(13): 138101, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31697512

RESUMO

Multipartite viruses have a genome divided into different disconnected viral particles. A majority of multipartite viruses infect plants; very few target animals. To understand why, we use a simple, network-based susceptible-latent-infectious-recovered model. We show both analytically and numerically that, provided that the average degree of the contact network exceeds a critical value, even in the absence of an explicit microscopic advantage, multipartite viruses have a lower threshold to colonizing network-structured populations compared to a well-mixed population. We further corroborate this finding on two-dimensional lattice networks, which better represent the typical contact structures of plants.

6.
Artigo em Inglês | MEDLINE | ID: mdl-31711662

RESUMO

Super-amphiphilic (highly oleophilic and hydrophilic) materials have attracted tremendous interest for fundamental research and potential applications, owing to their unique affinity for both oil and water. In this work, a novel super-amphiphilic porous polycaprolactone (PCL) was fabricated via an efficient and eco-friendly method, in which stearic acid (SA) was used as both a porogen and a dopant precursor. The porous PCL had an interconnected hierarchical pore structure and was capable of absorbing oil and water rapidly. The complementary cooperation of the oleophilic and hydrophilic domains on the pore surface induced the amphiphilicity, while the capillary forces caused a wicking action. The synergy of the two effects gave rise to the super-wetting property. The special amphiphilic feature of the porous PCL had a positive effect on its biocompatibility and the material can be considered as a promising candidate for tissue engineering applications.

7.
J Med Syst ; 43(12): 333, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31713093

RESUMO

The original article unfortunately contained a mistake. The corresponding author's name should be corrected as "Yingsheng Cheng".

8.
Anal Chem ; 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31714062

RESUMO

With the ever-increasing demand for improved medical diagnosis, safe food supply, advanced biotechnology, and sustainable ecosystems, characterization of microbial world by sensitive, specific, rapid, and quantitative tools is gaining more and more attentions. Surface-enhanced Raman spectroscopy (SERS) and their flexible integration with other tools, such as microscope, stable isotope probing, microfluidic analysis, and chemometric analysis, have advanced rapidly and showed great promise for versatile microbial characterization. This perspective provides an overview of the recent advances of SERS and related coupling techniques for microbial diagnosis (e.g., identification and antibiotic resistance testing), phenotypic response profiling, microbial function assessment, in situ biofilm characterization, and multifunctional SERS tags. We further propose the future requirement and direction for SERS methodology to be headed, including standardization of SERS methodology, database generation and management, coupling with omics technology and single-cell sorting.

9.
Phys Rev Lett ; 123(15): 156801, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31702286

RESUMO

We propose a realization of the lattice-symmetry-assisted second-order topological superconductors with corner Majorana zero modes (MZM) based on two-dimensional topological insulators (2DTI). The lattice symmetry can naturally lead to the anisotropic coupling of edge states along different directions to the in-plane magnetic field and conventional s-wave pairings, thus leading to a single MZM located at the corners for various lattice patterns. In particular, we focus on the 2DTI with D_{3d} lattice symmetry and found different types of gap opening for the edge states along the armchair and zigzag edges in a broad range of parameters. As a consequence, a single MZM exists at the corner between the zigzag and armchair edges, and is robust against weakly broken lattice symmetry. We propose to realize such corner MZMs in a variety of polygon patterns, such as triangles and quadrilaterals. We further show their potentials in building the Majorana network through constructing the Majorana Y junction under an in-plane magnetic field.

10.
12.
Small ; : e1904545, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31588653

RESUMO

Aqueous Zn-MnO2 batteries using mild electrolyte show great potential in large-scale energy storage (LSES) application, due to high safety and low cost. However, structure collapse of manganese oxides upon cycling caused by the conversion mechanism (e.g., from tunnel to layer structures for α-, ß-, and γ-phases) is one of the most urgent issues plaguing its practical applications. Herein, to avoid the phase conversion issue and enhance battery performance, a structurally robust novel phase of manganese oxide MnO2 H0.16 (H2 O)0.27 (MON) nanosheet with thickness of ≈2.5 nm is designed and synthesized as a promising cathode material, in which a nanosheet structure combined with a novel H+ /Zn2+ synergistic intercalation mechanism is demonstrated and evidenced. Accordingly, a high-performance Zn/MON cell is achieved, showing a high energy density of ≈228.5 Wh kg-1 , impressive cyclability with capacity retention of 96% at 0.5 C after 300 cycles, as well as exhibiting rate performance of 115.1 mAh g-1 at current rate of 10 C. To the best current knowledge, this H+ /Zn2+ synergistic intercalation mechanism is first reported in an aqueous battery system, which opens a new opportunity for development of high-performance aqueous Zn ion batteries for LSES.

13.
Int J Mol Med ; 44(6): 2311-2320, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31573048

RESUMO

Resveratrol (RS) has been reported to prevent the development of cardiac injury induced by pulmonary embolism (PE). The present study aimed to explore the potential mechanism of RS involved in cardiac injury induced by PE. A luciferase assay was conducted to detect the effect of RS on promoter efficiency of metastasis associated lung adenocarcinoma transcript 1 (MALAT1), in­silico analysis and luciferase assays were performed to explore the regulatory relationship between MALAT1, microRNA (miR)­22­3p and NLRP3. Reverse transcription PCR, western blot analysis and ELISA were carried out to examine MALAT1, miR­22­3p, NLRP3, ASC, Caspase­1, interleukin (IL)­1ß and IL­18 among different animal model groups, including the sham group, PE associated cardiac injury group and PE associated cardiac injury plus RS group. The results revealed that RS downregulated promoter efficiency of MALAT1 and MALAT1 directly targeted miR­22­3p, and luciferase activity of MALAT1 was inhibited by miR­22­3p, and furthermore miR­22­3p inhibited the expression of NLRP3 by binding to complementary sequences in the 3' untranslated region of NLRP3. MALAT1, NLRP3, ASC, Caspase­1, IL­1ß and IL­18 levels were much increased, while miR­22­3p level was much decreased in PE associated cardiac injury group compared with the sham group, while the RS upon the PE associated cardiac injury group slightly reduced the upregulated MALAT1/NLRP3 level and elevated the downregulated miR­22­3p level. In conclusion, it was demonstrated that RS has been demonstrated to prevent the development of cardiac injury induced by PE via modulating the expression of MALAT1 and further affect miR­22­3p and NLRP3.

14.
Nanoscale ; 11(42): 19823-19831, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31633141

RESUMO

Plant-derived chlorophyll derivatives with a porphyrin ring structure and intrinsic photosynthesis have been widely used in biomedicine for cancer theranostics. Owing to their poor water solubility, chlorophyll derivatives are very difficult to use in biomedical applications. In this work, pyropheophorbide acid (PPa) (liposome/PPa) nanoparticles, a liposome-encapsulated chlorophyll derivative, are designed for tri-model imaging guided photodynamic therapy (PDT) of cancer. The obtained liposome/PPa nanoparticles significantly enhance the water solubility of PPa, prolong blood circulation and optimize the bio-distribution in mice after intravenous injection. Utilizing their intrinsic fluorescence, high near-infrared (NIR) absorbance and extra radiolabeling, liposome/PPa nanoparticles could be used as excellent contrast agents for multimodal imaging including fluorescence (FL) imaging, photoacoustic (PA) imaging and SPECT/CT imaging. Under 690 nm laser irradiation at a low power density, liposome/PPa nanoparticles significantly inhibit tumor growth, further demonstrating the therapeutic efficiency of PDT using PPa. Therefore, our work developed liposome/PPa nanoparticles as multifunctional nanoagents for multimodal imaging guided PDT of cancer. This will further prompt the clinical applications of PPa in the future.

15.
J Mol Cell Cardiol ; 137: 9-24, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31629737

RESUMO

BACKGROUND: Cardiomyopathy is a common and lethal complication in patients with limb-girdle muscular dystrophy (LGMD), one of the most prevalent forms of muscular dystrophy. The pathogenesis underlying LGMD-related cardiomyopathy remains unclear. NRIP (gene name DCAF6), a Ca2+-dependent calmodulin binding protein, was reduced in dystrophic muscles from LGMD patients. Mice lacking NRIP exhibit a myopathic phenotype resembling that in LGMD patients, making NRIP deficiency a potential culprit leading to cardiomyopathy. This study aimed to determine if NRIP deficiency leads to cardiomyopathy and to explore the underlying molecular mechanisms. METHODS AND RESULTS: NRIP expression was reduced in both human and mouse failing hearts. Muscle-specific NRIP knockout (MCK-Cre::Dcaf6flox/flox) mouse heart and isolated cardiomyocytes exhibited markedly reduced contractility. Transmission electron microscopy revealed abnormal sarcomere structures and mitochondrial morphology in MCK-Cre::Dcaf6flox/flox hearts. Protein co-immunoprecipitation and confocal imaging revealed that NRIP interacts with α-actinin 2 (ACTN2) at the Z-disc. We found that NRIP facilitated ACTN2-mediated F-actin bundling, and that NRIP deficiency resulted in reduced binding between Z-disc proteins ACTN2 and Cap-Z. In addition, NRIP-deficiency led to increased mitochondrial ROS and impaired mitochondrial respiration/ATP production owing to elevated cellular NADH/NAD+ ratios. Treatment with mitochondria-directed antioxidant mitoTEMPO or NAD+ precursor nicotinic acid restored mitochondrial function and cardiac contractility in MCK-Cre::Dcaf6flox/flox mice. CONCLUSIONS: NRIP is essential to maintain sarcomere structure and mitochondrial/contractile function in cardiomyocytes. Our results revealed a novel role for NRIP deficiency in the pathogenesis of LGMD and heart failure. Targeting NRIP, therefore, could be a powerful new approach to treat myocardial dysfunction in LGMD and heart failure patients.

16.
PLoS One ; 14(10): e0223849, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31652266

RESUMO

This paper examines network prominence in a co-prescription network as an indicator of opioid doctor shopping (i.e., fraudulent solicitation of opioids from multiple prescribers). Using longitudinal data from a large commercially insured population, we construct a network where a tie between patients is weighted by the number of shared opioid prescribers. Given prior research suggesting that doctor shopping may be a social process, we hypothesize that active doctor shoppers will occupy central structural positions in this network. We show that network prominence, operationalized using PageRank, is associated with more opioid prescriptions, higher predicted risk for dangerous morphine dosage, opioid overdose, and opioid use disorder, controlling for number of prescribers and other variables. Moreover, as a patient's prominence increases over time, so does their risk for these outcomes, compared to their own average level of risk. Results highlight the importance of co-prescription networks in characterizing high-risk social dynamics.

17.
Nat Commun ; 10(1): 4815, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31645571

RESUMO

Nanoconfinement could dramatically change molecular transport and reaction kinetics in heterogeneous catalysis. Here we specifically design a core-shell nanocatalyst with aligned linear nanopores for single-molecule studies of the nanoconfinement effects. The quantitative single-molecule measurements reveal unusual lower adsorption strength and higher catalytic activity on the confined metal reaction centres within the nanoporous structure. More surprisingly, the nanoconfinement effects on enhanced catalytic activity are larger for catalysts with longer and narrower nanopores. Experimental evidences, including molecular orientation, activation energy, and intermediate reactive species, have been gathered to provide a molecular level explanation on how the nanoconfinement effects enhance the catalyst activity, which is essential for the rational design of highly-efficient catalysts.

18.
World J Gastroenterol ; 25(37): 5667-5675, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31602166

RESUMO

BACKGROUND: Hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) is a syndrome with a high short-term mortality rate, and it is crucial to identify those patients at a high mortality risk clinically. AIM: To investigate the clinical value of soluble mannose receptor (sMR) in predicting the 90-day mortality of HBV-ACLF patients. METHODS: A total of 43 patients were diagnosed with HBV-ACLF between October 2017 and October 2018 at the Second Hospital of Anhui Medical University, and all of them were enrolled in this retrospective study. Their serum sMR levels were determined using an enzyme-linked immunosorbent assay. Demographic and clinical data, including gender, age, albumin level, total bilirubin (TBIL) level, international normalized ratio, HBV-DNA level, HBV serological markers, procalcitonin level, interleukin-6 level, and model for end-stage liver disease (MELD) score were accessed at the time of diagnosis of HBV-ACLF. A multivariate logistic regression analysis was used to analyze the independent risk factors for mortality. RESULTS: Serum sMR level was significantly increased in HBV-ACLF patients compared with chronic hepatitis B patients and healthy controls (P < 0.01). When compared with surviving patients, it was higher in those patients who succumbed to HBV-ACLF (P < 0.05). Serum sMR level was positively correlated with MELD score (r s = 0.533, P = 0.001), HBV-DNA level (r s = 0.497, P = 0.022), and TBIL level (r s = 0.894, P < 0.001). Serum sMR level (odds ratio = 1.007, 95% confidence interval: 1.004-1.012, P = 0.001) was an independent risk factor for the 90-day mortality in the HBV-ACLF cases. The patients with HBV-ACLF were stratified into two groups in accordance with their serum sMR levels at the baseline (low risk: < 99.84 pg/mL and high risk: ≥ 99.84 pg/mL). The 90-day mortality rates were 27.3% in the low-risk group and 87.5% in the high-risk group. Furthermore, sMR level apparently improved the performance of MELD score for predicting the prognosis of patients with HBV-ACLF. CONCLUSION: Serum sMR level may be a predictor of the prognosis of HBV-ACLF patients.

19.
Sensors (Basel) ; 19(20)2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31618875

RESUMO

The ageing population has grown quickly in the last half century with increased longevity and declining birth rate. This presents challenges to health services and the wider society. This review paper considers different aspects (e.g., physical, mental, and social well-being) of healthy ageing and how health devices can help people to monitor health conditions, treat diseases and promote social interactions. Existing technologies for addressing non-physical (e.g., Alzheimer's, loneliness) and physical (e.g., stroke, bedsores, and fall) related challenges are presented together with the drivers and constraints of using e-textiles for these applications. E-textiles provide a platform that enables unobtrusive and ubiquitous deployment of sensors and actuators for healthy ageing applications. However, constraints remain on battery, integration, data accuracy, manufacturing, durability, ethics/privacy issues, and regulations. These challenges can only effectively be met by interdisciplinary teams sharing expertise and methods, and involving end users and other key stakeholders at an early stage in the research.

20.
Skeletal Radiol ; 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31612246

RESUMO

OBJECTIVE: To evaluate organ dose and total effective dose of whole-body low-dose CT (WBLDCT) performed on different CT-scanner models in patients with multiple myeloma (MM) and to compare it to the effective dose of radiographic skeletal survey and representative diagnostic CTs. MATERIAL AND METHODS: We retrospectively analyzed data from 228 patients (47.4% females, mean age 67.9 ± 10.4 years, mean weight 81.8 ± 22.4 kg) who underwent WBLDCT for the work-up or surveillance of MM. Patients were scanned using one of six multi-detector CT-scanners. Organ doses and total effective doses per scan were calculated using a commercially available dose-management platform (Radimetrics, Bayer Healthcare, Leverkusen, Germany). The median effective dose was compared to radiographic skeletal survey and representative diagnostic CTs. RESULTS: The mean effective dose of our WBLDCT-protocol was 4.82 mSv. A significantly higher effective dose was observed in females compared to males (4.95 vs. 4.70 mSv, P = 0.002). Mean organ dose ranged from 3.72 mSv (esophagus) to 13.09 mSv (skeleton). Mean effective dose varied amongst different CT-scanners (range 4.34-8.37 mSv). The median effective dose of WBLDCT was more than twice the dose of a skeletal survey (4.82 vs. 2.04 mSv), 23% higher than a diagnostic contrast-enhanced chest CT (3.9 mSv), 46% lower than a diagnostic contrast-enhanced abdomen/pelvis CT (9.0 mSv), and 45% lower than a lumbar spine CT (8.7 mSv). CONCLUSIONS: WBLDCT in MM has a higher effective dose than a radiographic skeletal survey, but a lower effective dose than diagnostic CTs of lumbar spine, abdomen and pelvis. This underlines the broad applicability of WBLDCT in the management of MM patients.

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