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1.
Food Chem ; 366: 130572, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34284190

RESUMO

In this study, a fluorine-fluorine interaction approach through fluoridating boron nitride nanosheets (BNNs) for sensing perfluoroalkyl acids (PFAAs) in multiple food matrices was developed. Through a facile hydrothermal fluorination modification, the BNNs were transferred into homogeneous fluorinated boron nitride nanoparticles (F-BNNs) with robust networks and specific surface area. After morphological modification, the particles displayed strong adsorption and sensing capabilities on PFAAs in both solid and liquid food matrix. Under the evaluation of mass spectrometry, F-BNNs based microextraction approach exhibited low method detection limits (MDLs) in the ranges of 0.9-3.9 pg mL-1 and 3.6-15.8 pg g-1 for milk and meat matrices, respectively, with satisfactory repeatability (RSD% <13.5%) and recoveries (77.7-110.5%). This work not only depicted a facile approach for preparing F-BNNs based SPME fiber, but also provided a routine analysis protocol for monitoring PFAAs in food systems.

2.
Artigo em Inglês | MEDLINE | ID: mdl-34472598

RESUMO

AIM: To determine the effects of slow breathing exercise (SBE) on heart rate (HR) and blood pressure (BP) in patients after percutaneous coronary intervention (PCI). METHODS AND RESULTS: The study is a single-blind, randomized controlled trial. Seventy-eight eligible patients after primary PCI were divided randomly into either the control group or the trial group. The control group only received routine post-PCI care. In addition to routine care, participants in the trial group performed SBE at home, two to three times for a total of 30 min every day for 12 weeks. The main outcomes were HR and BP measured in the office and at home. The secondary outcome was compliance with the breathing exercise. Patients allocated to the trial group, on average, performed 5.21 days/week for 26.00 min/day. The trial group showed a significant reduction in HR of 3.95 b.p.m. (P = 0.004) measured in the office. The reduction in HR measured in the office was greater for the trial group, with a significant difference between the two groups (P = 0.005). There was no significant difference between the two groups in HR measured at home. There was also no significant difference in BP measured in the office or at home between the two groups. CONCLUSION: Slow breathing exercise is an effective non-pharmacological method to reduce HR in patients undergoing PCI. Further study is needed to confirm whether the intervention is effective on BP.

3.
Econ Model ; : 105639, 2021 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-34539023

RESUMO

Preliminary evidence indicates that pollution increases the severity and likelihood of COVID-19 infections similar to many other infectious diseases. This paper models the interaction of pollution and disease preventive actions, either pharmaceutical or non-pharmaceutical interventions, on transmission of infectious diseases in a neoclassical growth framework. There are two externalities - households do not take into account how their actions affect disease transmission, and productive activity results in pollution which increases the likelihood of infections. The disease dynamics are modeled to be of SIS type. We study the difference in health and economic outcomes between the decentralized economy, where households do not internalize externalities, and socially optimal outcomes, and characterize the taxes and subsidies that decentralize the latter. Thus, we examine the question whether there are sufficient incentives to reduce pollution, at both private and public levels, once its effects on disease transmission is considered. In competitive outcomes, pollution increases with increased productivity. The socially efficient outcome has higher pollution than a competitive outcome, despite increase in abatement, as the effect of higher productivity and larger labor supply dominates. The results question the hopes of a Green Recovery.

4.
J Hypertens ; 39(10): 1982-1990, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34493696

RESUMO

BACKGROUND: Hypertension is associated with increased postoperative risk. However, no consensus was accepted whether elevated blood pressure in the operating room with normal blood pressure at rest related to additional cardiovascular risk. METHODS: This was a single-center retrospective cohort study based on patients who underwent elective noncardiac surgery from 1 January 2012, to 31 December 2018. We evaluated the relationship between the delta SBP (the difference between first operating room blood pressure and baseline blood pressure) and the development of postoperative major adverse cardiac events (MACEs) in patients with normal baseline blood pressure. Multivariate logistic regression before and after propensity score weighting was performed to adjust for perioperative variables, and the minimum P value approach was used to identify the possible threshold of delta SBP that independently indicated the risk of MACE. RESULTS: Of the 55 563 surgeries, in 4.1%, postoperative MACE occurred. The threshold for the delta SBP was 49 mmHg. The adjusted odds ratio for MACE before and after propensity score weighting for the delta SBP threshold was 1.35 (95% CI, 1.11--1.59); P less than 0.001 and 1.28 (1.03-1.60); P = 0.028, respectively. CONCLUSION: Delta SBP contributed to the elevated risk over and beyond the SBP at rest in patients who underwent elective noncardiac surgery. A rise of SBP of more than 49 mmHg from baseline in the operating room was significantly associated with an increased risk of postoperative MACE.

5.
Clin Nucl Med ; 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34507335

RESUMO

ABSTRACT: 68Ga-labeled quinoline-based fibroblast activation protein inhibitors (68Ga-FAPIs) are promising agents for tumor imaging. However, some nonneoplastic lesions can also cause increased FAPI uptake. We report a case of a patient with polyostotic fibrous dysplasia who showed widespread and intense metabolic activity on 68Ga-FAPI PET/CT. Physicians should be aware that fibrous dysplasia can also cause elevated FAPI activity.

6.
Artigo em Inglês | MEDLINE | ID: mdl-34467752

RESUMO

In ferroelectric-based integrated devices, there are usually buffer layers between ferroelectric films and semiconductor substrates. Here, Bix%FeO3-δ (x = 95, 100, and 105) (BFOx) films are prepared directly on n-Si substrates by the sol-gel method, and the variation of the hysteresis loops with Bi content and heat treatment is investigated. With the help of the dielectric measurement and the composition analysis, a PN heterojunction is believed to exist at the BFOx/Si interface. The Bi/Fe ratio determines not only the type and concentration of charged defects in the films but also the height of the interface barrier and its binding effect on mobile charges. Furthermore, the distribution and the migration of charges can be regulated reversibly by heat treatment. This work reveals the interaction between ferroelectric films and semiconductor substrates, providing an important reference for the design and application of ferroelectric/semiconductor heterostructures.

7.
Artigo em Inglês | MEDLINE | ID: mdl-34529580

RESUMO

Multilabel feature selection plays an essential role in high-dimensional multilabel learning tasks. Existing multilabel feature selection approaches mainly either explore the feature-label and feature-feature correlations or the label-label and feature-feature correlations. A few of them are able to deal with all three types of correlations simultaneously. To address this problem, in this article, we formulate multilabel feature selection as a local causal structure learning problem and propose a novel algorithm, M2LC. By learning the local causal structure of each class label, M2LC considers three types of feature relationships simultaneously and is scalable to high-dimensional datasets as well. To tackle false discoveries caused by the label-label correlations, M2LC consists of two novel error-correction subroutines to correct those false discoveries. Through local causal structure learning, M2LC learns the causal mechanism behind data, and thus, it can select causally informative features and visualize common features shared by class labels and specific features owned by an individual class label using the learned causal structures. Extensive experiments have been conducted to evaluate M2LC in comparison with the state-of-the-art multilabel feature selection algorithms.

8.
Neurochirurgie ; 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34543615

RESUMO

BACKGROUND: Oligodendrocyte precursor cells (OPCs) are myelinated glial cells of the central nervous system (CNS), able to regenerate oligodendrocytes and myelin. This study aimed to elucidate the effect of A2B5-positive (A2B5+) OPC transplantation in rats with spinal cord contusion (SCC) and to investigate changes in expression of various factors involved in the Notch signaling pathway after OPC transplantation. METHODS: OPCs were obtained from induced pluripotent stem cells (iPSCs) originating from mouse embryo fibroblasts (MEFs). After identification of iPSCs and iPSC-derived OPCs, A2B5+OPCs were transplanted into the injured site of rats with SCC one week after SCC insult. Behavioral tests evaluated motor and sensory function 7 days after OPC transplantation. Real-time quantitative polymerase chain reaction (RT-qPCR) determined the expression of various cytokines related to the Notch signaling pathway after OPC transplantation. RESULTS: IPSC-derived OPCs were successfully generated from MEFs, as indicated by positive immunostaining of A2B5, PDGFα and NG2. Further differentiation of OPCs was identified by immunostaining of Olig2, Sox10, Nkx2.2, O4, MBP and GFAP. Importantly, myelin formation was significantly enhanced in the SCC+OPC group and SCI-induced motor and sensory dysfunction was largely alleviated by A2B5+OPC transplantation. Expression of factors involved in the Notch signaling pathway (Notch-1, Numb, SHARP1 and NEDD4) was significantly increased after OPC transplantation. CONCLUSIONS: A2B5+OPC transplantation attenuates motor and sensory dysfunction in SCC rats by promoting myelin formation, which may be associated with change in expression of factors involved in the Notch signaling pathway.

9.
Sci Rep ; 11(1): 18591, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34545152

RESUMO

Environmental exposures interact with genetic factors has been thought to influence susceptibility of systemic lupus erythematosus (SLE) development. To evaluate the effects of environmental exposures on SLE, we conducted a population-based cohort study across Jiangsu Province, China, to examine the associations between the living environment including air and water pollution, population density, economic income level, etc. and the prevalence and mortality of hospitalized SLE (h-SLE) patients. A total of 2231 h-SLE patients were retrieved from a longitudinal SLE database collected by the Jiangsu Lupus Collaborative Group from 1999 to 2009. The results showed that: It existed regional differences on the prevalence of h-SLE patients in 96 administrative districts; The distribution of NO2 air concentration monitored by atmospheric remote sensors showed that three of the ultra-high-prevalence districts were located in the concentrated chemical industry emission area; h-SLE patient prevalence was positively correlated with the excessive levels of nitrogen in drinking water; The positive ratio of pericarditis and proteinuria was positively correlated with the prevalence of h-SLE patients and pollution not only induced a high h-SLE patient prevalence but also a higher mortality rate, which might be attributed to NOx pollution in the air and drinking water. In summary, our data suggested that NOx in air and drinking water may be one of the important predispositions of SLE, especially for patients with renal involvement.

10.
Sci Rep ; 11(1): 17791, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34493750

RESUMO

The purpose of this study is to explore whether uric acid (UA) can independently act as a prognostic factor and critical marker of the 2019 novel corona virus disease (COVID-19). A multicenter, retrospective, and observational study including 540 patients with confirmed COVID-19 was carried out at four designated hospitals in Wuhan. Demographic, clinical, laboratory data were collected and analyzed. The primary end point was in-hospital death of patients with COVID-19. The concentration of admission UA (adUA) and the lowest concentration of uric acid during hospitalization (lowUA) in the dead patients were significantly lower than those in the survivors. Multivariate logistic regression analysis showed the concentration of lowUA (OR 0.986, 95% CI 0.980-0.992, p < 0.001) was able to independently predict the risk of in-hospital death. The mean survival time in the low-level group of lowUA was significantly lower than other groups. When lowUA was ≤ 166 µmol/L, the sensitivity and specificity in predicting hospital short-term mortality were 76.9%, (95% CI 68.5-85.1%) and 74.9% (95% CI 70.3-78.9%). This retrospective study determined that the lowest concentration of UA during hospitalization can be used as a prognostic indicator and a marker of disease severity in severe patients with COVID-19.


Assuntos
COVID-19/mortalidade , Ácido Úrico/sangue , Adulto , Idoso , Biomarcadores/sangue , COVID-19/sangue , COVID-19/diagnóstico , China/epidemiologia , Estudos de Viabilidade , Feminino , Mortalidade Hospitalar , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Medição de Risco/métodos , Fatores de Risco , Sensibilidade e Especificidade , Índice de Gravidade de Doença
11.
Bioengineered ; 12(1): 6529-6537, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34519635

RESUMO

Hepatocellular carcinoma (HCC) is a serious malignant tumor of the liver. It has been reported that serine/threonine kinase 39 (STK39) participates in tumorigenesis. However, the role of STK39 in HCC remains unknown. In this study, the qRT-PCR and western blot assay demonstrated that STK39 expression was enhanced in HCC patients and tissues. Moreover, CCK-8 and colony formation assays confirmed that knockdown of STK39 suppressed SK-HEP-1 and Huh7 cells proliferation. Furthermore, wound healing assay and transwell assay revealed that knockdown of STK39 repressed SK-HEP-1 and Huh7 cells migration and invasion. Interestingly, knockdown of STK39 reduced p-p38/p38 ratio and levels of c-Myc. Consistently, knockdown of STK39 inhibited the HCC tumor growth in vivo. In summary, knockdown of STK39 suppressed the proliferation, migration, and invasion of HCC cells by inducing the lower levels of p-p38, which might provide a novel therapeutic target for HCC.

12.
Artigo em Inglês | MEDLINE | ID: mdl-34530161

RESUMO

BACKGROUND AND AIMS: Artificial intelligence-based computer aided polyp detection (CADe) systems are intended to address the issue of missed polyps during colonoscopy. The effect of CADe during screening and surveillance colonoscopy has not previously been studied in a United States population. METHODS: We conducted a prospective, multi-center, single-blind randomized tandem colonoscopy study to evaluate a deep-learning based CADe system (EndoScreener, Shanghai Wision AI, China). Patients were enrolled across four U.S. academic medical centers from 2019 through 2020. Patients presenting for colorectal cancer screening or surveillance were randomized to CADe colonoscopy first or high-definition white light (HDWL) colonoscopy first, followed immediately by the other procedure in tandem fashion by the same endoscopist. The primary outcome was adenoma miss rate (AMR), and secondary outcomes included sessile serrated lesion (SSL) miss rate and adenomas per colonoscopy (APC). RESULTS: 2 32 patients entered the study, with 116 patients randomized to the AI-assisted colonoscopy first and 116 patients to HDWL colonoscopy first. After the exclusion of 9 patients, the study cohort was 223. AMR was lower in the CADe-first group compared to the HDWL-first group: 20.12% (34/169) versus 31.25% (45/144) (P=0.0247), (OR) 1.8048 (95% CI 1.0780-3.0217). SSL miss rate was lower in the CADe-first group, 7.14% (1/14) versus the HDWL-first group, 42.11% (8/19) (P=0.0482). First-pass APC was higher in the CADe-first group (1.19 (SD 2.03) versus 0.90 (SD 1.55), (P=0.0323)). First-pass ADR was 50.44% in the CADe-first group and 43.64 % in the HDWL-first group (P=0.3091). CONCLUSION: In this U.S. multicenter tandem colonoscopy RCT, we demonstrate a decrease in adenoma miss rate and SSL miss rate and an increase in first-pass APC with the use of a CADe-system when compared to HDWL colonoscopy.

14.
Sensors (Basel) ; 21(17)2021 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-34502583

RESUMO

In recent years, the rapid development of Deep Learning (DL) has provided a new method for ship detection in Synthetic Aperture Radar (SAR) images. However, there are still four challenges in this task. (1) The ship targets in SAR images are very sparse. A large number of unnecessary anchor boxes may be generated on the feature map when using traditional anchor-based detection models, which could greatly increase the amount of computation and make it difficult to achieve real-time rapid detection. (2) The size of the ship targets in SAR images is relatively small. Most of the detection methods have poor performance on small ships in large scenes. (3) The terrestrial background in SAR images is very complicated. Ship targets are susceptible to interference from complex backgrounds, and there are serious false detections and missed detections. (4) The ship targets in SAR images are characterized by a large aspect ratio, arbitrary direction and dense arrangement. Traditional horizontal box detection can cause non-target areas to interfere with the extraction of ship features, and it is difficult to accurately express the length, width and axial information of ship targets. To solve these problems, we propose an effective lightweight anchor-free detector called R-Centernet+ in the paper. Its features are as follows: the Convolutional Block Attention Module (CBAM) is introduced to the backbone network to improve the focusing ability on small ships; the Foreground Enhance Module (FEM) is used to introduce foreground information to reduce the interference of the complex background; the detection head that can output the ship angle map is designed to realize the rotation detection of ship targets. To verify the validity of the proposed model in this paper, experiments are performed on two public SAR image datasets, i.e., SAR Ship Detection Dataset (SSDD) and AIR-SARShip. The results show that the proposed R-Centernet+ detector can detect both inshore and offshore ships with higher accuracy than traditional models with an average precision of 95.11% on SSDD and 84.89% on AIR-SARShip, and the detection speed is quite fast with 33 frames per second.


Assuntos
Radar , Navios
15.
Oxid Med Cell Longev ; 2021: 6116890, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34512868

RESUMO

Baicalein has been shown to have chondroprotective potential in vitro. However, its effect on disease modification in osteoarthritis (OA) is largely unknown. The present study is aimed at determining whether baicalein could slow the progression of OA and inhibit OA-related inflammation in a rat model of destabilization of the medial meniscus (DMM) and the underlying mechanisms. The rats subjected to DMM surgery were treated with baicalein (0.8, 1.6, and 3.2 µg/L, 50 µL, once a week) by intra-articular injection for 6 weeks. Dexamethasone (0.4 mg/mL, 50 µL, once a week) was used as a positive control. Histologic grading of cartilage degeneration was performed using the Osteoarthritis Research Society International (OARSI) recommended grading system (on a scale of 0-6). The expression levels of molecules associated with cartilage homeostasis and inflammatory cytokines were analyzed; moreover, the NLRP3 inflammasome activation and cartilage oxidative stress-associated molecules were determined. Baicalein treatment reduced the OARSI score and slowed OA disease progression in a dose-dependent manner within a certain range. Compared with DMM rats, intra-articular injection of baicalein led to (1) reduced levels of inflammatory mediates such as IL-1ß and TNF-α, (2) reduced immunochemical staining of MMP-13 and ADAMTS-5, (3) suppressed immunochemical staining loss of type II collagen, (4) reduced expression of cartilage degradation markers including CTX-II and COMP in urine, and (5) inhibited NLRP3 inflammasome activation rather than regulated expression of SOD, GSH, and MDA. In contrast to the administration of baicalein, dexamethasone injection showed similar effects to slow OA progression, while dexamethasone inhibited NLRP3 inflammasome partly through decreasing levels of SOD, GSH, and MDA. This study indicated that baicalein may have the potential for OA prevention and exerts anti-inflammatory effects partly via suppressing NLRP3 inflammasome activation without affecting oxidative stress-associated molecules, and inhibition of cartilage catabolism enzymes in an OA rat model.

16.
Artigo em Inglês | MEDLINE | ID: mdl-34519490

RESUMO

Electrochemical CO2 reduction reaction (CO2RR) coupled with hydrogen evolution reaction (HER) is a renewable route to produce syngas (CO + H2), an essential feedstock for liquid fuel production. However, the development of high-performance electrocatalyst with tunable H2/CO ratio, high-rate syngas production, and long-term electrochemical stability remains challenging. Here, a metal three-dimensional (3D) printing technique followed by dealloying was utilized to develop three-dimensional hierarchical porous (termed as 3D hp) CuAg catalysts for the concurrent generation of CO and H2. By purposely designing the precursor compositions, the resultant 3D hp CuAg catalysts with a high density of phase-segregated Ag and Cu nanodomains exhibit a tunable H2/CO ratio from 3:1 to 1:2. Through further porosity engineering, the 3D hp CuAg catalysts show significantly enhanced syngas production rate of 140 µmol/h/cm2 and electrochemical stability up to 140 h (which is the highest value reported so far). The remarkable electrochemical stability of the 3D hp CuAg arises from three-level hierarchical porous configurations, wherein the macroporous structure benefits gas bubble growth and detachment, the microporous structure stabilizes the active nanoporous layer, while the nanoporous structure provides a large active surface area and enables efficient mass transfer. The results of this study offer a new vision for the development of hierarchically porous catalysts for CO2 reduction.

17.
Dalton Trans ; 50(35): 12074-12078, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34519730

RESUMO

Cs-Loaded MgO, a typical type of solid superbase, was used as a support to disperse and anchor Ru nanoparticles. Much enhanced Ru dispersion together with electron donation of Cs-loaded MgO enables Ru nanoparticles on Cs-loaded MgO to exhibit excellent activity and intrinsic activity for ammonia synthesis, superior to the conventional Ru/MgO catalyst and the state-of-the-art Cs modified Ru/MgO catalyst under identical reaction conditions.

18.
BMC Genomics ; 22(1): 664, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34521344

RESUMO

BACKGROUND: Root hair, a special type of tubular-shaped cell, outgrows from root epidermal cell and plays important roles in the acquisition of nutrients and water, as well as interactions with biotic and abiotic stress. Although many genes involved in root hair development have been identified, genetic basis of natural variation in root hair growth has never been explored. RESULTS: Here, we utilized a maize association panel including 281 inbred lines with tropical, subtropical, and temperate origins to decipher the phenotypic diversity and genetic basis of root hair length. We demonstrated significant associations of root hair length with many metabolic pathways and other agronomic traits. Combining root hair phenotypes with 1.25 million single nucleotide polymorphisms (SNPs) via genome-wide association study (GWAS) revealed several candidate genes implicated in cellular signaling, polar growth, disease resistance and various metabolic pathways. CONCLUSIONS: These results illustrate the genetic basis of root hair length in maize, offering a list of candidate genes predictably contributing to root hair growth, which are invaluable resource for the future functional investigation.


Assuntos
Estudo de Associação Genômica Ampla , Zea mays , Resistência à Doença , Fenótipo , Polimorfismo de Nucleotídeo Único , Zea mays/genética
19.
Comput Intell Neurosci ; 2021: 9654059, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34545284

RESUMO

The vestibular system is the sensory apparatus that helps the body maintain its postural equilibrium, and semicircular canal is an important organ of the vestibular system. The semicircular canals are three membranous tubes, each forming approximately two-thirds of a circle with a diameter of approximately 6.5 mm, and segmenting them accurately is of great benefit for auxiliary diagnosis, surgery, and treatment of vestibular disease. However, the semicircular canal has small volume, which accounts for less than 1% of the overall computed tomography image. Doctors have to annotate the image in a slice-by-slice manner, which is time-consuming and labor-intensive. To solve this problem, we propose a novel 3D convolutional neural network based on 3D U-Net to automatically segment the semicircular canal. We added the spatial attention mechanism of 3D spatial squeeze and excitation modules, as well as channel attention mechanism of 3D global attention upsample modules to improve the network performance. Our network achieved an average dice coefficient of 92.5% on the test dataset, which shows competitive performance in semicircular canals segmentation task.

20.
Chem Commun (Camb) ; 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34550120

RESUMO

With the development of controlled polymerisation, almost all polymerisation strategies have been successfully transplanted to surface-initiated polymerisation. The resulting polymer brushes have emerged as an effective tool for surface functionalization and modulation of the surface properties of materials. To meet various demands it is possible to tailor a material surface with polymer brushes that have diverse dimensionalities, morphologies and compositions. The crowded environment within polymer brushes as well as the stretched conformation of polymer chains sometimes provide unique physicochemical properties, which lead to the delicate creation of inorganic-organic hybridised nanostructures, anti-fouling coatings, biomedical carriers, and materials for use in lubrication, photonics and energy storage. So far, challenges remain in the high-precision synthesis and topological control needed to realize extended applications of polymer brushes. In this Feature Article, we highlight the topology, potential application prospects and various synthetic protocols, particularly for recently established methods, for the efficient synthesis of polymer brushes, as well as their benefits and limitations.

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