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1.
Ann Pharmacother ; : 1060028020987679, 2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33423508

RESUMO

OBJECTIVE: To review the pharmacological characteristics, clinical evidence, and place in the management of acute postoperative pain severe enough to require an intravenous opioid. DATA SOURCES: A comprehensive literature search was conducted in PubMed (January 2000 to December 1, 2020). Key search terms included oliceridine or acute postoperative pain. Other sources were derived from product labeling and ClinicalTrials.gov. STUDY SELECTION AND DATA EXTRACTION: All English-language articles identified from the data sources were reviewed and evaluated. Phase I, II, and III clinical trials were included. DATA SYNTHESIS: Oliceridine is a novel selective µ-receptor G-protein pathway modulator. It has the property of activating G-protein signaling while causing low ß-arrestin recruitment to the µ-receptor. Intravenous oliceridine showed statistically superior analgesia than placebo in patients with moderate or severe pain after surgery, with a favorable safety and tolerability profile regarding respiratory and gastrointestinal adverse effects, compared with morphine. RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE: The analgesic capacity of oliceridine is at least comparable to that of morphine at clinically relevant dosages, with a rapid onset of action. Also, it may be associated with a lower incidence of adverse events at dosing regimens associated with comparable analgesia. These data suggest that oliceridine may provide an important new treatment option for the management of moderate to severe postoperative pain where an intravenous opioid is warranted. CONCLUSION: Oliceridine has obvious analgesic effects in patients with moderate or severe pain after surgery; additionally, it has a favorable safety and tolerability profile.

2.
Carbohydr Polym ; 252: 117137, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33183596

RESUMO

Bacterial cellulose (BC) and polyhydroxybutyrate (PHB) are microbial polymers considered to be promising biodegradable alternatives to fossil fuel derivatives. BC and PHB can be combined into a composite with enhanced mechanical properties. The synthesis processes of BC/PHB composites described until now are complicated with multiple steps. Here, BC/PHB composites were synthesized by a facile Gluconacetobacter xylinus and Ralstonia eutropha co-culture method generating BC and PHB simultaneously in situ. This co-culture approach ensured a certain level of control over the synthesis process. By simply varying the R. eutropha inoculum, the weight ratio of PHB into BC/PHB was adjusted from 15.62 to 42.88 %. The fabricated composites were networks of BC fibers connecting PHB particles. BC/PHBs were characterized by thermal and mechanical analyses and exhibited a 2.6 times higher capacity for toxic copper adsorption than pure BC. The co-culture technique described here is a simple synthesis method to obtain BC/PHB with adjustable characteristics.

3.
J Nanosci Nanotechnol ; 21(2): 1169-1175, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33183458

RESUMO

This article prepared a simvastatin-NLCs for the treatment of arteriosclerotic occlusive disease of lower limbs. Taking the size distribution, polydispersity coefficient, encapsulation efficiency and drug loading of simvastatin-NLCs as evaluation indicators, various prescription factors of simvastatin- NLCs were investigated. The in vitro release behavior and stability of simvastatin-NLCs were also investigated. A hyperlipidemia rat model was established using high-fat diets. SD rats fed ordinary diet were set as normal control groups. 20 rats, 20 in the simvastatin group and 20 in the simvastatin nanocarrier group. After 5 weeks of drug intervention, the rats were sacrificed and the aorta was taken to determine the smooth muscle cell apoptosis rate. Studies have shown that simvastatin nanocarriers can more effectively reduce blood lipids in hyperlipidemia rats, increase the rate of smooth muscle cell apoptosis in hyperlipidemia rats, and delay the onset of atherosclerosis.

4.
ACS Omega ; 5(47): 30495-30501, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33283098

RESUMO

In this paper, the flame propagation characteristics and overpressure oscillation characteristics of CH4 explosion were studied under different ignition positions (IPs) and oxygen enrichment conditions in a half-open tube. The distances between the IP and the closed end of the tube are 0, 250, 500, and 750 mm. The oxygen enrichment coefficient (φ) values used in the experiment are 0.21, 0.3, and 0.4. The experimental results show that the IP and oxygen enrichment coefficient have an important influence on the flame structure and overpressure oscillation. Only when the oxygen enrichment coefficient φ = 0.21, a tulip flame will be formed. The IP close to the outlet can make the air participate in the combustion more quickly. With the increase of the oxygen enrichment coefficient, the combustion-induced rapid phase transition phenomenon is more likely to occur, and the maximum overpressure value and the overpressure rise rate of flame will increase. It is worth noting that after increasing the oxygen enrichment coefficient, the IP has less influence than the oxygen enrichment coefficient on the overpressure rise rate.

5.
Eur Urol Open Sci ; 22: 34-44, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33299986

RESUMO

Background: Metastatic prostate cancer (CaP) treatments are evolving rapidly but without evidence-based biomarkers to predict responses, and to maximize remissions and survival. Objective: To determine the activity of androgen receptor (AR), the target for default first-line systemic treatment, in localized treatment-naïve CaP and its association with clinical risk factors, molecular markers, CaP subtypes, and predictors of treatment response. Design setting and participants: We examined 452 bona fide AR target genes in clinical-grade expression profiles from 6532 such CaPs collected between 2013 and 2017 by US physicians ordering the Decipher RP test. Results were validated in three independent smaller cohorts (n = 73, 90, and 127) and clinical CaP AR ChIP-Seq data. Association with CaP differentiation and progression was analyzed in independent datasets. Outcome measurements and statistical analysis: Unsupervised clustering of CaPs based on AR target gene expression was aligned with clinical variables, differentiation scores, molecular subtypes, and predictors of response to hormonal therapy, radiotherapy, and chemotherapy. AR target gene sets were analyzed via Gene Set Enrichment Analysis for differentiation and treatment resistance, Ingenuity Pathway Analysis for associated biology, and Cistrome for genomic AR binding site (ARBS) composition. Results and limitations: Expression of eight AR target gene subsignatures gave rise to five CaP clusters, which were preferentially associated with CaP molecular subtypes, differentiation, and predictors of treatment response rather than with clinical variables. Subsignatures differed in contribution to CaP progression, luminal/basal differentiation, CaP biology, and ARBS composition. Validation in prospective trials and optimized quantitation are needed for clinical implementation. Conclusions: Measurement of AR activity patterns in treatment-naïve CaP may serve as a first branch of an evidence-based decision tree to optimize personalized treatment plans. Patient summary: Treatment options for metastatic prostate cancer are increasing without information needed to choose the right treatment for the right patient. We found variation in the behavior of the target for the default first-line therapy before treatment, which may help optimize treatment plans.

6.
Appl Radiat Isot ; 169: 109445, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33340788

RESUMO

In the research, the Nuclide Identification and Quantitative Analysis System (NIQAS) for the identification of hazardous goods was designed and optimized by MCNP simulations. With the D-T neutron generator and HPGe detector set as the core of device, the modules, including reflector, moderator and shielding, etc., were optimized by a Signal-to-Noise Ratio (SNR) evaluation method. Moreover, the NIQAS device was set up for measuring the hazardous goods, and the type identification was discussed based on the established logical decision. Finally, a Graphical User Interface (GUI) was designed and the minimum detection time was further investigated.

8.
Sheng Wu Gong Cheng Xue Bao ; 36(11): 2478-2493, 2020 Nov 25.
Artigo em Chinês | MEDLINE | ID: mdl-33244942

RESUMO

Filamentous microalga Tribonema sp. has the advantages of highly resistance to zooplankton-predation, easy harvesting, and high cellular lipid content, in particular large amounts of palmitoleic acid (PA) and eicosapentaenoic acid (EPA). Therefore, Tribonema sp. is considered as a promising biomass feedstock to produce biodiesel and high-value products. In this work, we studied the effect of different concentrations of nitrogen (NaNO3: 255-3 060 mg/L), phosphorus (K2HPO4: 4-240 mg/L), iron ((NH4)3FeC12H10O14: 0.6-12 mg/L) and magnesium (MgSO4: 7.5-450 mg/L) on the biomass, lipid content, and fatty acid composition of Tribonema sp. FACHB-1786, aiming at enhancing cell lipid productivity. The growth of Tribonema sp. had a positive correlation with the concentration of magnesium, and the maximum biomass of Tribonema sp. (under the condition of 450 mg/L MgSO4) was 8.09 g/L, much greater than those reported in previous studies using the same and other Tribonema species under autotrophic conditions. Different nitrogen concentrations exerted no significant effect on algal growth (P > 0.05), but a higher nitrogen concentration resulted in a greater amount of lipid in the cells. The maximum volumetric productivities of total lipids (319. 6 mg/(L·d)), palmitoleic acid (135.7 mg/(L·d)), and eicosapentaenoic acid (24.2 mg/(L·d)) of Tribonema sp. were obtained when the concentrations of NaNO3, K2HPO4, (NH4)3FeC12H10O14, and MgSO4 were 765 mg/L, 80 mg/L, 6 mg/L, and 75 mg/L, respectively. This study will provide a reference for substrate optimization for Tribonema sp. growth and lipid production.

9.
Dis Colon Rectum ; 63(9): e511, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-33216505
10.
J Pak Med Assoc ; 70(10): 1727-1730, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33159742

RESUMO

OBJECTIVE: To investigate the clinical characteristics of early recurrent intussusception after ultrasound-guided saline reduction, and to explore the factors leading to early recurrence. Methods: The retrospective observational case-control study was conducted at Weifang People's Hospital, Shandong, China, and comprised data from January 2015 to December 2017 related to paediatric intussusception patients aged 0-12 years who underwent ultrasound-guided saline enema reduction. The patients were divided into two recurrent and non-recurrent groups. Clinical characteristics of the patients with early recurrence were analysed. Factors compared between the groups were gender, age, onset season, onset-to-treatment time interval, blood in stool, fever, diarrhoea, abdominal pain and vomiting, weight and pathology. Data was analysed using SPSS 22. RESULTS: Of the 672 subjects, 86(13%) were patient with early recurrence while 586(87%) had no early recurrence and acted as controls. Among the patients, 70(81.4%) were aged 6-36 months. In 52(60.5%) patients, recurrence was once, and in 23(26.7%) twice. There were 141 episodes of intussusception; 24(17%) occurring in <12 hours, 85(60.2%) in 12-24 hours. Also, 5(6%) patients required surgery for reduction. Compared to the controls, the second quarter, heavier body weight and pathology were the factors leading to early recurrence of intussusceptions (p<0.05). CONCLUSIONS: The second quarter, heavier body weight and pathological leading points were found to be factors leading to early recurrent intussusception.

11.
Sci Total Environ ; : 143820, 2020 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-33248779

RESUMO

Biochar, produced as a by-product of pyrolysis/gasification of waste biomass, shows great potential to reduce the environment impact, address the climate change issue, and establish a circular economy model. Despite the promising outlook, the research on the benefits of biochar remains highly debated. This has been attributed to the heterogeneity of biochar itself, with its inherent physical, chemical and biological properties highly influenced by production variables such as feedstock types and treating conditions. Hence, to enable meaningful comparison of results, establishment of an agreed international standard to govern the production of biochar for specific uses is necessary. In this study, we analyzed four key uses of biochar: 1) in agriculture and horticulture, 2) as construction material, 3) as activated carbon, and 4) in anaerobic digestion. Then the guidelines for the properties of biochar, especially for the concentrations of toxic heavy metals, for its environmental friendly application were proposed in the context of Singapore. The international status of the biochar industry code of practice, feedback from Singapore local industry and government agencies, as well as future perspectives for the biochar industry were explained.

12.
Artigo em Inglês | MEDLINE | ID: mdl-33180735

RESUMO

Deep neural networks (DNNs) are shown to be excellent solutions to staggering and sophisticated problems in machine learning. A key reason for their success is due to the strong expressive power of function representation. For piecewise linear neural networks (PLNNs), the number of linear regions is a natural measure of their expressive power since it characterizes the number of linear pieces available to model complex patterns. In this article, we theoretically analyze the expressive power of PLNNs by counting and bounding the number of linear regions. We first refine the existing upper and lower bounds on the number of linear regions of PLNNs with rectified linear units (ReLU PLNNs). Next, we extend the analysis to PLNNs with general piecewise linear (PWL) activation functions and derive the exact maximum number of linear regions of single-layer PLNNs. Moreover, the upper and lower bounds on the number of linear regions of multilayer PLNNs are obtained, both of which scale polynomially with the number of neurons at each layer and pieces of PWL activation function but exponentially with the number of layers. This key property enables deep PLNNs with complex activation functions to outperform their shallow counterparts when computing highly complex and structured functions, which, to some extent, explains the performance improvement of deep PLNNs in classification and function fitting.

13.
Dalton Trans ; 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-33078788

RESUMO

Owing to the considerable theoretical energy density, lithium-sulfur batteries have been deemed as a competitive candidate for the next-generation energy storage devices. However, its commercialization still depends on the moderation of the shuttle effect and the conductivity improvement of the sulfur cathode. Herein, a novel reduced graphene oxide (rGO) wrapped yolk-shell vanadium dioxide (VO2) sphere hybrid host (rGO/VO2) is reported to simultaneously tackle these barriers. In particular, the polar VO2 sphere can chemically anchor and catalyze the conversion of polysulfides effectively both on the yolk and the shell surfaces. Meanwhile, the highly conductive 3D porous rGO network not only allows sufficient penetration of electrolyte and provides efficient transport pathways for lithium ions and electrons, but also buffers the volume variation during the lithiation process. Besides, the dissolution of the polysulfides can also be alleviated by physical confinement via the interconnected carbon network. Benefiting from these synergistic features, such designed rGO/VO2/S cathode delivers outstanding cycle stability (718.6 mA h g-1 initially, and 516.1 mA h g-1 over 400 cycles at 1C) with a fading rate of 0.07% per cycle. Even at 3C, a capacity of 639.7 mA h g-1 is reached. This proposed unique structure could provide novel insights into high-energy batteries.

14.
Colloids Surf B Biointerfaces ; 197: 111372, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-33017715

RESUMO

Clinical extensive application of indocyanine green (ICG) is limited by several drawbacks such as poor bioenvironmental stability, aggregate propensity, and rapid elimination from the body, etc. In this study, we construct a novel amphiphilic mPEG-ACA-ICG conjugate by modifying synthetic heptamethine cyanine derivative ICG-COOH with a hydrophobic linker 6-aminocaproic acid (ACA) and amino-terminal poly(ethylene glycol) (mPEG-NH2). The as-prepared mPEG-ACA-ICG conjugate has the ability to self-assemble into micellar aggregates in an aqueous solution with a lower CMC value than mPEG-ICG conjugate without ACA linker. More importantly, compared with free ICG and mPEG-ICG conjugate, mPEG-ACA-ICG nanomicelles exhibited better stability and higher photothermal conversion efficiency upon near-infrared light irradiation due to the intramolecular introduction of a hydrophobic ACA segment. In our in vivo experiment, mPEG-ACA-ICG nanomicelles ensured the formidable effect on tumor photothermal therapy (PTT) and the maximum tumor inhibition rate reached 72.6 %. In addition, real-time determination ability for fluorescence image-guided surgery (FIGS) of mPEG-ACA-ICG nanomicelles was also confirmed on tumor xenograft mice model. Taken together, mPEG-ACA-ICG conjugate may hold great promise for non-invasive cancer theranostics.

15.
Plant J ; 2020 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-33103271

RESUMO

Nannochloropsis species, unicellular industrial oleaginous microalgae, are model organisms for microalgal systems and synthetic biology. To facilitate community-based annotation and mining of the rapidly accumulating functional genomics resources, we have initiated an international consortium and present a comprehensive multi-omics resource database named Nannochloropsis Design and Synthesis (NanDeSyn; http://nandesyn.single-cell.cn). Via the Tripal toolkit, it features user-friendly interfaces hosting genomic resources with gene annotations and transcriptomic and proteomic data for six Nannochloropsis species, including two updated genomes of Nannochloropsis oceanica IMET1 and Nannochloropsis salina CCMP1776. Toolboxes for search, Blast, synteny view, enrichment analysis, metabolic pathway analysis, a genome browser, etc. are also included. In addition, functional validation of genes is indicated based on phenotypes of mutants and relevant bibliography. Furthermore, epigenomic resources are also incorporated, especially for sequencing of small RNAs including microRNAs and circular RNAs. Such comprehensive and integrated landscapes of Nannochloropsis genomics and epigenomics will promote and accelerate community efforts in systems and synthetic biology of these industrially important microalgae.

17.
Ecotoxicol Environ Saf ; 208: 111497, 2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-33091773

RESUMO

The potential nephrotoxicity of polyfluoroalkyl chemicals (PFCs) have received extensive attention. However, the relationship between PFCs and the risk of kidney stones remain unclear. This study aimed to examine the level of PFCs in the US population and its relationship with the risk of kidney stones. We investigated the serum levels of six PFCs in 8453 adult participants (≥20 years) from the National Health and Nutrition Examination Survey (NHANES) between 2007 and 2016, including perfluorodecanoic acid (PFDE), perfluorohexane sulfonic acid (PFHS), 2-(N-methyl-perfluorooctane sulfonamido) acetate (MPAH), perfluorononanoic acid (PFNA), perfluoroundecanoic acid (PFUA), and perfluorododecanoic acid (PFDO). Logistic regression model was used to evaluate the correlation between PFCs and kidney stones. Of the 8453 participants, 787 self-reported a history of kidney stones. After adjusting for gender, age, race, education, marital status, body mass index (BMI), hypertension, diabetes and estimated glomerular filtration rate (eGFR), we found that total PFCs and PFHS were positively correlated with the risk of kidney stones. Compared with the lowest tertile, the odds ratios with 95% confidence intervals (CI) with increasing tertiles were 1.30 (95% CI,1.08-1.59, p = 0.007) and 1.25 (95 CI%,1.00-1.52, p = 0.024) for total PFCs and 1.24 (95 CI%,1.03-1.51, p = 0.032), and 1.35 (95 CI,1.10-1.68, p = 0.005) for PFHS. Our study shows that total PFCs and PFHS were associated with an increased risk of kidney stones.

18.
J Exp Bot ; 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33005924

RESUMO

Acyl-CoA: diacylglycerol acyltransferase (DGAT) catalyzes the final committed step in triacylglycerol (TAG) biosynthesis in eukaryotes. In microalgae, the copy number of DGAT genes is extraordinarily expanded and yet the functions of many DGATs remain largely unknown. This study revealed microalgal DGAT can function as lysophosphatidic acyltransferase (LPAAT) both in vitro and in vivo while losing its original function as DGAT. Among the five DGAT encoding genes identified and cloned from the green microalga Haematococcus pluvialis, four encodes HpDGATs that showed TAG synthase activities in yeast for functional complementation analysis, except for one of the type II DGAT encoding genes, i.e., HpDGTT2 gene. The hydrophobic recombinant HpDGTT2 was purified in a soluble form and was revealed to function as a LPAAT via enzymatic assay. Introducing this gene into the green microalga Chlamydomonas reinhardtii led to retarded cellular growth, enlarged cell size and enhanced TAG accumulation, identical to the phenotypes of the transgenic strains with overexpressed CrLPAAT. This study provides a framework for dissecting uncharacterized DGATs, and could pave the way to decrypt the structure-function relationship of this large group of enzymes critical to lipid biosynthesis.

19.
Carbohydr Polym ; 250: 116909, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33049884

RESUMO

The conversion of sunlight into H2 by noble-metal-free photocatalysts is a promising approach for the production of easy-to-store chemical energy. For this purpose, higher efficiency is achieved by photocatalysts with heterojunctions preventing fast charge recombination. Most processes for the synthesis of high-performance heterojunction photocatalysts require solvents harmful to living organisms. Here, berry-shaped (b)-CdS/MoS2 particles were fabricated instead by a hydrothermal process where non-toxic bacterial cellulose was used to mold b-CdS into nanostructures with enhanced spatial arrangement. Subsequently, MoS2 was combined with b-CdS resulting in a composite with suitable shape and intimate semiconductor contacts beneficial for charge transfer. The photocatalytic H2 evolution (PHE) of b-CdS/1%MoS2 was 63.59 mmol g-1 h-1. It was 61.1 times, 397 times, and 10.2 times higher than PHE with b-CdS, CdS fabricated without BC scaffold, and b-CdS doped with Pt, respectively. These results show the high potential of b-CdS/MoS2 and the associated synthesis method for PHE.

20.
Front Plant Sci ; 11: 544827, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32983212

RESUMO

Microalgae are promising feedstocks for starch production, which are precursors for bioenergy and chemicals manufacturing. Though starch biosynthesis has been intensively studied in the green alga Chlamydomonas reinhardtii, regulatory mechanisms governing starch metabolism in this model species have remained largely unknown to date. We proposed that altering triacylglycerol (TAG) biosynthesis may trigger intrinsic regulatory pathways governing starch metabolism. In accordance with the hypothesis, it was observed in this study that overexpression of the plastidial lysophosphatidic acid acyltransferase gene (i.e. LPAAT1) in C. reinhardtii significantly enhanced TAG biosynthesis under nitrogen (N)-replete conditions, whereas the starch biosynthesis was enhanced in turn under N depletion. By the exploitation of transcriptomics analysis, a putative regulatory gene coding Gcn5-related N-acetyltransferase (GNAT19) was identified, which was up-regulated by 11-12 times in the CrLPAAT1 OE lines. Overexpression of the cloned full-length CrGNAT19 cDNA led to significant increase in the starch content of C. reinhardtii cells grown under both N-replete and N-depleted conditions, which was up to 4 times and 26.7% higher than that of the empty vector control, respectively. Moreover, the biomass yield of the CrGNAT19 OE lines reached 1.5 g L-1 after 2 days under N-depleted conditions, 72% higher than that of the empty vector control (0.87 g L-1). Overall, the yield of starch increased by 118.5% in CrGNAT19 OE lines compared to that of the control. This study revealed the great biotechnical potentials of an unprecedented GNAT19 gene in enhancing microalgal starch and biomass production.

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