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1.
ACS Nano ; 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-33016066

RESUMO

Rational design of metal-free multifunctional therapeutic reagents offers great opportunities for cancer treatment in the clinic. Here, graphitic carbon nitride (g-C3N4) quantum dots embedded in carbon nanosheets (CNQD-CN) are in situ prepared via a one-pot hydrothermal approach with formamide as carbon and nitrogen source. The CNQD-CN not only serves as an excellent near-infrared (NIR) fluorescent marker but also acts as a pH-responsive nanocarrier. Moreover, the CNQD-CN possesses both light-to-heat conversion and singlet oxygen generation capabilities under a single NIR excitation wavelength. Further investigations show that systemic delivery of doxorubicin (DOX) using the multifunctional CNQD-CN nanocarrier under NIR irradiation was highly effective to cause cancer cell apoptosis in vitro and inhibit tumor growth in vivo. CNQD-CN represents a multifunctional therapeutic platform for synchronous cancer imaging and treatment through the synergistic effect of phototherapy and chemotherapy.

2.
Artigo em Inglês | MEDLINE | ID: mdl-33063901

RESUMO

PURPOSE: To investigate factors that influence parental decisions to use orthokeratology (ortho-k) as a myopia control method for their children, and parents' perspectives during children's ortho-k treatment in a hospital setting. METHODS: Parents/guardians of children wearing ortho-k lenses for at least six months were required to complete a face-to-face survey to investigate the reasons for choosing ortho-k and their experience of the treatment. RESULTS: Parents/guardians of 128 ortho-k wearers were recruited from the West China Hospital, Sichuan, China. The majority of the participants (74%) were mothers. Wearers' mean age at the time of the survey was 12.0 ± 2.0 years, with a mean history of ortho-k lens wear of 20.3 ± 8.0 months. Most participants had learned about ortho-k through word of mouth (56%) or from ophthalmologists (40%); in China, only ophthalmologists may prescribe ortho-k. The highest ranked motivation was the rapid progression of their children's myopia (54%), followed by ophthalmologists' advice (17%) or participants' who felt they had obtained enough knowledge (17%) of ortho-k (Kruskal-Wallis test, p = 0.002). 'Effectiveness' was the most common reason that participants decided to use ortho-k (81%), and potential injury was their major concern (75%). Itchy/sore eye was the most common initial adverse effect experienced with lens wear (22%), while a lost or broken ortho-k lens was the most frequently reported problem (34%). Parents of older lens wearers were significantly less involved in all procedures (Spearman rank correlation test, all p < 0.001). Most wearers, according to either the participants or the wearers themselves, were willing to wear ortho-k lenses at treatment commencement (80%), and the most common reason was 'to avoid having to wear spectacles in the daytime'. CONCLUSIONS: The most powerful motivation for parents to enrol their children in ortho-k treatment was the rapid progression of myopia. The main reason why participants chose ortho-k, which most participants learned of by word of mouth, was the effectiveness of the treatment. During use, the most common symptom reported was itchy or sore eyes, but only initially. Children's willingness to participate is very important for successful ortho-k treatment; however, their motivation can be quite different from that of their parents. Ortho-k is a well-accepted option for myopia control in children.

3.
J Cell Physiol ; 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33044023

RESUMO

Random-pattern skin flaps are widely applied to rebuild and restore soft-tissue damage in reconstructive surgery; however, ischemia and subsequent ischemia-reperfusion injury lead to flap necrosis and are major complications. Exenatide, a glucagon-like peptide-1 analog, exerts therapeutic benefits for diabetic wounds, cardiac injury, and nonalcoholic fatty liver disease. Furthermore, Exenatide is a known activator of autophagy, which is a complex process of subcellular degradation that may enhance the viability of random skin flaps. In this study, we explored whether exenatide can improve skin flap survival. Our results showed that exenatide augments autophagy, increases flap viability, enhances angiogenesis, reduces oxidative stress, and alleviates pyroptosis. Coadministration of exenatide with 3-methyladenine and chloroquine, potent inhibitors of autophagy, reversed the beneficial effects, suggesting that the therapeutic benefits of exenatide for skin flaps are due largely to autophagy activation. Mechanistically, we identified that exenatide enhanced activation and nuclear translocation of TFE3, which leads to autophagy activation. Furthermore, we found that exenatide activates the AMPK-SKP2-CARM1 and AMPK-mTOR signaling pathways, which likely lead to exenatide's effects on activating TFE3. Overall, our findings suggest that exenatide may be a potent therapy to prevent flap necrosis, and we also reveal novel mechanistic insight into exenatide's effect on flap survival.

4.
Environ Res ; 189: 109891, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32979997

RESUMO

Potassium ions (K+) present in wastewater has caused severe interference for NH4+ monitoring, over-estimation of NH4+ concentration and ultimately leads to extra energy consumption. Past effort for enhancing the selectivity of NH4+ over K+ were oftentimes complex, costly, or compromised the selectivity and accuracy of the NH4+ ion selective membrane (ISM) sensors. This study targeted this imminent challenge by developing an integrated NH4+/K+ auto-correction solid-state ISM (S-ISM) sensor assembly combined with a data-driven model to monitor [NH4+] under different [NH4+] and [K+] concentrations. The results showed that the interference of K+ was substantially alleviated for NH4+ measurement. The accuracy was enhanced by over 70% when examined using real wastewater and energy consumption was expected to reduce by 26% for a wastewater treatment plant, especially for wastewater with high [K+]. Furthermore, the uniquely structured S-ISMs were made by embedding the ionophores in a robust polyvinyl chloride (PVC) matrix containing plasticizers and a layer of carbon nanotubes (CNT) as ion-to-electron transducer, which maintained the selectivity and accuracy of the S-ISM sensor for 4 weeks in wastewater. NH4+/K+ sensor assembly integrated with data-driven correction models poses great potential in high-efficiency and energy-saving wastewater treatment and water reuse processes.

5.
J Food Biochem ; : e13462, 2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32954518

RESUMO

Colorectal cancer, the most common malignancy in Asian and west world, is listed as the fourth lethal neoplastic disease with increasing incidence worldwide. Recently, Ziziphus jujube were reported with hepatoprotective, antihypertensive, and hypoglycemic functions. The polysaccharides from Ziziphus jujube was considered as the main component for these bioactivities. In this study, polysaccharides from Ziziphus jujube cv. Goutouzao (GZSP) was comprehensively investigated, and characterized as a heteropolysaccharide with antioxidant activity. Besides, it can stimulate the viability of immune cells RAW 264.7, which in turn inhibited the proliferation of colorectal carcinoma cells (LoVo) by inducing apoptosis, arresting cell cycle in G0/G1, and increasing intracellular ROS, as demonstrated by Flow Cytometric analyses. The results suggest that, different from chemotherapeutic modalities, GZSP can exert antitumor effects by activating immune reaction, providing more evidence for the development of GZSP-based functional foods and anticancer drugs serving as human colon cancer prevention. PRACTICAL APPLICATIONS: Natural products from medicinal and edible plant are great sources of phytochemicals beneficial to human health, such as tea polyphenols, carotenoids, and phytosterols, etc. In this study, GZSP, the polysaccharides from a well-received fruit, Ziziphus jujube cv. Goutouzao, has been comprehensively investigated. The results show that GZSP fights against free radicals commonly found in human circulation, a property that enables it to be used as an antioxidant food additive with jujube flavor. More importantly, GZSP impedes neoplastic progression by activating immune response, as evidenced by the inhibition of colorectal carcinoma (LoVo) cells. Comparing with chemotherapies usually imposing cytotoxicity on normal tissues, natural product GZSP is able to exert the antiproliferative effects on carcinoma cells with minimal side-effects. Therefore, GZSP-based functional foods and anticancer drugs with the purpose of preventing human colon cancer formation are promising to be developed.

6.
IEEE Trans Neural Syst Rehabil Eng ; 28(10): 2153-2163, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32870796

RESUMO

The performance of motor imagery (MI) based Brain-computer interfacing (BCI) is easily affected by noise and redundant information that exists in the multi-channel electroencephalogram (EEG). To solve this problem, many temporal and spatial feature based channel selection methods have been proposed. However, temporal and spatial features do not accurately reflect changes in the power of the oscillatory EEG. Thus, spectral features of MI-related EEG signals may be useful for channel selection. Bispectrum analysis is a technique developed for extracting non-linear and non-Gaussian information from non-linear and non-Gaussian signals. The features extracted from bispectrum analysis can provide frequency domain information about the EEG. Therefore, in this study, we propose a bispectrum-based channel selection (BCS) method for MI-based BCI. The proposed method uses the sum of logarithmic amplitudes (SLA) and the first order spectral moment (FOSM) features extracted from bispectrum analysis to select EEG channels without redundant information. Three public BCI competition datasets (BCI competition IV dataset 1, BCI competition III dataset IVa and BCI competition III dataset IIIa) were used to validate the effectiveness of our proposed method. The results indicate that our BCS method outperforms use of all channels (83.8% vs 69.4%, 86.3% vs 82.9% and 77.8% vs 68.2%, respectively). Furthermore, compared to the other state-of-the-art methods, our BCS method also can achieve significantly better classification accuracies for MI-based BCI (Wilcoxon signed test, p < 0.05).

7.
Plant Dis ; 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32815485

RESUMO

Polygonatum cyrtonema Hua, also known as Huangjing, is an important traditional Chinese herb for treating diabetes and asthma. This plant is commercially planted (approximately 700 ha) in the highland of Anhui Province in China (Liu et al. 2016). In June 2019, brown spots on the leaves of P. cyrtonema Hua were frequently observed in the field in Jinzhai County, Anhui Province. Disease incidence varied from 20 to 30% in a survey site (3 ha) of approximately 25,000 plants. Initially circular or elliptical, reddish colored spots with well-defined brown margin were observed on infected leaves. With time, the spots expanded to large elliptical or shuttle-shaped, pale to dark brown lesions within 10-15 days. To identify the pathogen, symptomatic tissues from the lesion margin were excised from fifteen infected leaves, surface sterilized with 2% NaClO for 2 min, 70% ethanol for 30 s, rinsed three times with sterile water, air dried, plated on potato dextrose agar (PDA) medium supplemented with cefotaxime sodium salt (150 µg/ml), and incubated at 26°C for 3 to 4 days in the dark. Eight morphologically similar fungal isolates were obtained by single-sporing. On PDA, colonies were initially white, and turned pale gray with age. On the reverse side, colonies were initially pale brown and later turned dark black. Conidia were hyaline, curved or slightly curved, aseptate, with a truncate base and acute apex, and measured 14.38 to 20.57 × 2.03 to 5.28 µm (n = 50). The appressoria were solitary, dark brown, ovoid or irregularly shaped, with diameters from 5.61 to 12.43 µm (n = 50). These morphological characteristics are consistent with the description of a Colletotrichum species (Damm et al. 2009). For molecular identification, the primers ITS4/ITS5, T1/T2 and GDF/GDR were used to amplify the partial region of rDNA-ITS, ß-tubulin (TUB2) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) from fresh mycelia of all eight isolates, respectively. The resulting sequences of ITS, TUB2 and GAPDH were identical with each other, and sequences from strain PCCS-3 were submitted to Genbank. BlastN revealed that ITS (MN305792), TUB2 (MN307740) and GAPDH (MN307739) shared 99.8%, 100%, 98.8% similarity with the published ITS, TUB2 and GADPH sequences from the ex-epitype culture of C. spaethianum CBS 167.49 (Damm et al. 2009), respectively. To prove Koch's postulates, a pathogenicity test was conducted by spraying 3 ml of conidial suspension of each the eight isolates (105 conidia/ml) on three-month-old healthy P. cyrtonema seedlings (3 seedlings per isolate). As a control, three seedlings were sprayed with 3 ml of distilled water. All inoculated plants were maintained in a moist chamber (RH>90%) at 26°C, with an 8-h photoperiod under fluorescent light. The disease assays were repeated thrice. Brown spots identical to those observed in field were noted 7 to 10 days after inoculation, whereas control plants remained symptomless. The same pathogen was reisolated and confirmed as C. spaethianum by sequencing of ITS, GAPDH and Tub2, fulfilling Koch's postulates. Presently, C. spaethianum causing leaf spot on Polygonatum odoratum was reported from Jilin Province in China (Liu et al. 2020). To our knowledge, this is the first report of C. spaethianum infecting P. cyrtonema in Anhui Province, China. Our result expanded the geographic location of C. spaethianum as the pathogen on plants belonging to Asparagaceae family in China, and effective control strategies need to be considered to minimize the losses.

8.
Cancer Manag Res ; 12: 6303-6309, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32801875

RESUMO

Introduction: The molecular pathogenesis of liver cancer remains unclear; some ncRNAs have been considered as potential drug targets for cancer treatment. LncRNA PSMG3­AS1 has been reported to promote breast cancer, while its role in hepatocellular carcinoma (HCC) is unknown. Methods: Bioinformatics analysis was conducted to investigate the relationship between miR-143-3p and PSMG3-AS1. RT-qPCR was used to detect the expression levels of miR-143-3p and PSMG3-AS1 and the correlation between them in HCC. The survival curve was used to analyze the effect of PSMG3-AS1 on the prognosis of liver cancer. RT-qPCR was used to detect the effect of different concentration gradients of miR-143-3p on PSMG3-AS1. CCK8 and clone formation experiments were used to examine the role of miR-143-3p and PSMG3-AS1 in regulating the proliferation of SNU-182 and SNU-398 cells. Results: Our preliminary bioinformatics analysis showed that miR-143-3p can target PSMG3-AS1. We, therefore, analyzed the interaction between PSMG3-AS1 and miR-143-3p in HCC. We found that PSMG3-AS1 was upregulated, while miR-143-3p was downregulated in HCC. The expression levels of PSMG3­AS1 and miR-143-3p were closely and inversely correlated with each other. High expression levels of PSMG3­AS1 predicted poor survival. In HCC cells, overexpression of PSMG3-AS1 led to increased proliferation rates. Overexpression of miR-143-3p played an opposite role and reversed the effect of overexpression of PSMG3­AS1. Discussions: miR-143-3p may target PSMG3­AS1 to inhibit the proliferation of HCC cells.

9.
Artigo em Inglês | MEDLINE | ID: mdl-32833646

RESUMO

The common spatial pattern (CSP) algorithm is a well-recognized spatial filtering method for feature extraction in motor imagery (MI)-based brain-computer interfaces (BCIs). However, due to the influence of nonstationary in electroencephalography (EEG) and inherent defects of the CSP objective function, the spatial filters, and their corresponding features are not necessarily optimal in the feature space used within CSP. In this work, we design a new feature selection method to address this issue by selecting features based on an improved objective function. Especially, improvements are made in suppressing outliers and discovering features with larger interclass distances. Moreover, a fusion algorithm based on the Dempster-Shafer theory is proposed, which takes into consideration the distribution of features. With two competition data sets, we first evaluate the performance of the improved objective functions in terms of classification accuracy, feature distribution, and embeddability. Then, a comparison with other feature selection methods is carried out in both accuracy and computational time. Experimental results show that the proposed methods consume less additional computational cost and result in a significant increase in the performance of MI-based BCI systems.

10.
Proc Natl Acad Sci U S A ; 117(34): 20729-20740, 2020 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-32796104

RESUMO

Tissue-resident macrophages can originate from embryonic or adult hematopoiesis. They play important roles in a wide range of biological processes including tissue remodeling during organogenesis, organ homeostasis, repair following injury, and immune response to pathogens. Although the origins and tissue-specific functions of resident macrophages have been extensively studied in many other tissues, they are not well characterized in skeletal muscle. In the present study, we have characterized the ontogeny of skeletal muscle-resident macrophages by lineage tracing and bone marrow transplant experiments. We demonstrate that skeletal muscle-resident macrophages originate from both embryonic hematopoietic progenitors located within the yolk sac and fetal liver as well as definitive hematopoietic stem cells located within the bone marrow of adult mice. Single-cell-based transcriptome analyses revealed that skeletal muscle-resident macrophages are distinctive from resident macrophages in other tissues as they express a distinct complement of transcription factors and are composed of functionally diverse subsets correlating to their origins. Functionally, skeletal muscle-resident macrophages appear to maintain tissue homeostasis and promote muscle growth and regeneration.

11.
Anal Chem ; 92(18): 12670-12677, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32842725

RESUMO

We report a series of colorable zeolitic imidazolate framework (ZIF)-based nanomaterials prepared by encapsulating starches (amylopectin, dextrin, or amylose) or tannic acid in the frameworks of ZIFs and first applied them in colorimetric assay of microRNA/DNA by adding I2/KI or FeCl3 solutions as chromogenic reagents. We found that iodine molecules can lead to rapid degradation of the ZIF-8 framework, while ZIF-90 remains stable. Therefore, ZIF-90 was selected for encapsulating the starches or tannic acid, and then assembled with polyethylenimine (PEI) and aptamers of microRNA/DNA. After interacting with the target microRNA/DNA, the aptamers (Ap) move away from the surface of the prepared Ap-starch@ZIF-90 or Ap-tan@ZIF-90, and the I2/KI or FeCl3 solution is added into the system to interact the starches (amylopectin, dextrin, or amylose) or tannic acid to generate different colors. According to the absorbance spectra, good linear correlations between the logarithm of absorbance intensity and the concentration of microRNA (1-180 nM) can be observed, and the naked eye can distinguish the change from ∼60 to ∼180 nM with a concentration gradient of 20 nM. A similar colorimetric assay ability for pathogenic bacteria can also be realized by detecting the gene fragments IS200 and eaeA. The detection limits can be potentially optimized by changing the amount of adsorbed PEI and aptamers on the surface of Ap-starch@ZIF-90 (or Ap-tan@ZIF-90) nanoparticles. This method could be a promising alternative for simple and cost-effective assay of microRNA/DNA.

12.
Chemosphere ; 260: 127625, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32758776

RESUMO

Ultrafiltration (UF), nanofiltration (NF) and reverse osmosis (RO) are widely used in drinking water treatment and wastewater recycling. However, limited information was available regarding their performance in removing trihalomethanes (THMs). The present study investigated the effect of feed solution characteristics and membrane fouling on THM removal by UF/NF/RO membranes. The results indicated that THMs were poorly removed by UF membrane, and the removal was dominated by hydrophobic adsorption. In contrast, high removal of THMs was observed for NF/RO membranes, which was contributed by both size exclusion and hydrophobic adsorption. By comparing the adsorption of THMs on NF/RO membranes at different feed concentration, it was found that the role of hydrophobic adsorption was more important at lower feed concentration. The removal of THMs by UF/NF/RO membranes increased with increasing feed concentration, which can be ascribed to the enhanced diffusion at higher concentration gradient. With increasing ionic strength, THM removal was decreased significantly for UF membrane, but the removal by NF/RO membranes remained largely unchanged. By comparing THM removal by clean and fouled membranes, the effect of membrane fouling was examined. The removal of most THMs (except trichloromethane) decreased after fouling for UF membrane, whereas decreased removal was only observed for iodinated THMs for fouled NF/RO membranes.


Assuntos
Purificação da Água/métodos , Adsorção , Filtração , Halogenação , Interações Hidrofóbicas e Hidrofílicas , Membranas Artificiais , Concentração Osmolar , Osmose , Reciclagem , Trialometanos , Ultrafiltração/métodos , Águas Residuárias
13.
J Phys Chem A ; 2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32567315

RESUMO

In view of the appropriate physicochemical characteristics and environmental friendliness of the trans-1,1,1,4,4,4-hexafluoro-2-butene (HFO-1336mzz(E)) substance, the thermal-decomposition mechanism as well as the fire-extinguishing mechanism and performance of this agent were systematically studied by employing both experimental and theoretical methods in this work. We found that the HFO-1336mzz(E) agent not only has promising thermal stability at room temperature but also exhibits pronounced fire-extinguishing performance, which is comparable to that of HFC-236fa and even better than that of HFC-125 extinguishant. Additionally, the promising fire-extinguishing performance of HFO-1336mzz(E) may result from the physical and chemical extinguishing effect of its thermal-decomposition products including HFO-1336mzz(Z), HC≡CCF3, CF3C≡CCF3, and CF3H, which makes a significant contribution to capturing the free radicals in the flame, as well as cooling and diluting the combustible fuel-air mixture. Both experimental and theoretical results suggest that the HFO-1336mzz(E) agent is a highly recommendable candidate for Halon extinguishant, which is worthy of further investigation and evaluation of its practical applicability in fire-suppression utilization.

14.
J Pharm Pharmacol ; 72(9): 1152-1164, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32567690

RESUMO

OBJECTIVES: Icariin, extracted from Epimedium, is a kind of flavonoid and possesses osteogenesis and antioxidant. This study aimed to evaluate the therapeutic effects of icariin liposome on acute blunt skeletal muscle injury in rats. METHODS: Icariin liposome was prepared by the thin-film dispersion method. After muscle injury, the corresponding treatment measures were given every day for two weeks. Recovery and mechanism of muscle injury were evaluated by QRT-PCR, HE, immunohistochemistry, malondialdehyde, superoxide dismutase and serological tests. KEY FINDINGS: The particle size, polydispersity index, zeta potential, encapsulation efficiency and drug loading of icariin liposomes were 171.37 ± 38.23 nm, 0.27 ± 0.01, -5.59 ± 1.36 mV, 78.15 ± 2.04% and 15.62%, respectively. The QRT-PCR showed that icariin liposome significantly promoted the expression of MHCIIB and vimentin. Through HE, immunohistochemistry, ELISA and serological tests, we found that icariin liposome effectively promoted desmin expression, reduced collagen I expression and inhibited the production of pro-inflammatory factors, including TNF-α and IL-6. Icariin liposome therapy significantly reduced the level of malondialdehyde and increased the activity of superoxide dismutase. CONCLUSIONS: Icariin liposome has excellent therapeutic effects on acute blunt muscle injury in rats by improving immunity, repairing cytoskeleton and cellular integrity, anti-inflammation, anti-fibrosis and antioxidant stress.

15.
QJM ; 2020 May 22.
Artigo em Inglês | MEDLINE | ID: covidwho-342730

RESUMO

BACKGROUND: COVID-19 is a global pandemic but the follow-up data of discharged patients was barely described. AIMS: To investigate clinical outcomes, distribution of quarantine locations, and the infection status of the contacts of COVID-19 patients after discharge. DESIGN: A prospective cohort study. METHODS: Demographics, baseline characteristics of 131 COVID-19 patients discharged from February 3 to 21, 2020 in Wuhan, China were collected and analyzed by reviewing the medical records retrospectively. Post-hospitalization data related to clinical outcomes, quarantine locations and close contact history were obtained by following up the patients every week up to 4 weeks. RESULTS: 53 (40.05%) patients on discharge had cough (29.01%), fatigue (7.63%), expectoration (6.11%), chest tightness (6.11%), dyspnea (3.82%), chest pain (3.05%), and palpitation (1.53%). These symptoms constantly declined in 4 weeks post discharge. Transient fever recurred in 11 (8.4%) patients. 78 (59.5%) discharged patients underwent chest CT and 2 (1.53%) showed deterioration. 94 (71.8%) patients received SARS-CoV-2 retest and 8 (6.10%) reported positive. 7 (2.29%) patients were re-admitted because of fever or positive SARS-CoV-2 retest. 121 (92.37%) and 4 (3.05%) patients were self-quarantined at home or community spots following discharge, with totally 167 closely contacted persons free of COVID-19 at the endpoint of study. CONCLUSIONS: The majority of COVID-19 patients after discharge were in the course of recovery. Readmission was required in rare cases due to suspected recurrence of COVID-19. Although no contacted infection observed, appropriate self-quarantine and regular reexamination are necessary, particularly for those who have recurred symptoms.

16.
Dis Markers ; 2020: 9731854, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32454909

RESUMO

Background: Acute pancreatitis (AP) is a life-threatening disease caused by a variety of factors, and once it progresses to severe acute pancreatitis, the prognosis is poor. The purpose of this study was to investigate the diagnostic value of the neutrophil-lymphocyte ratio (NLR) for predicting the severity of acute pancreatitis. Materials and Methods: We searched the databases of PubMed, EMBASE, Web of Science, and Cochrane Library to identify eligible studies using the NLR to predict the severity of AP. The sensitivity (SEN), specificity (SPE), negative likelihood ratio (NLR), positive likelihood ratio (PLR), diagnostic odds ratio (DOR), and area under the receiver operating characteristic curve (AUC) were combined using a bivariate mixed model. Results: A total of 10 articles containing 394 cases and 1319 controls were included in the study. The combined SEN, SPE, NLR, PLR, DOR, and AUC are 79% (73%-84%), 71% (59%-80%), 0.30 (0.21-0.41), 2.7 (1.8-4.0), 9 (5-18), and 0.82 (0.78-0.85), respectively. Conclusions: NLR has a moderately high diagnostic value in predicting the severity of acute pancreatitis.

17.
Nanoscale ; 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32412575

RESUMO

The bottom-up synthesis of graphene quantum dots (GQDs) using solvothermal methods has attracted considerable attention because of their fewer defects and controllable size/morphology. However, the influence of organic solvents on the preparation of GQDs is still unknown. Herein, a systematic study on the carbonization of organic solvents toward GQDs is reported. The results show that organic solvents with the double bond or benzene ring or double hydrophilic groups could be directly decomposed into GQDs without the addition of catalysts or molecular precursors. The as-synthesized GQDs demonstrate ultra-small size distribution, high stability, tunable excitation wavelength and upconverted fluorescence. Both hematological and histopathological analyses show that the as-synthesized GQDs demonstrate a very good safety profile and excellent biocompatibility. The versatility of this synthesis strategy offers easy control of the surface group, composition, and optical properties of GQDs at the molecular level.

18.
Sci Rep ; 10(1): 5930, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32246077

RESUMO

We directly measure the electric dipole of InN quantum dots (QDs) grown on In-rich InGaN layers by Kelvin probe force microscopy. This significantly advances the understanding of the superior catalytic performance of InN/InGaN QDs in ion- and biosensing and in photoelectrochemical hydrogen generation by water splitting and the understanding of the important third-generation InGaN semiconductor surface in general. The positive surface photovoltage (SPV) gives an outward QD dipole with dipole potential of the order of 150 mV, in agreement with previous calculations. After HCl-etching, to complement the determination of the electric dipole, a giant negative SPV of -2.4 V, significantly larger than the InGaN bandgap energy, is discovered. This giant SPV is assigned to a large inward electric dipole, associated with the appearance of holes, matching the original QD lateral size and density. Such surprising result points towards unique photovoltaic effects and photosensitivity.

19.
J Neurosci Methods ; 340: 108725, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32311375

RESUMO

BACKGROUND: Motor imagery (MI) related features are typically extracted from a fixed frequency band and time window of EEG signal. Meanwhile, the time when the brain activity associated with the occurring task varies from person to person and trial to trial. Thus, some of the discarded EEG data with time may contain MI-related information. NEW METHOD: This study proposes a temporal frequency joint sparse optimization and fuzzy fusion (TFSOFF) method for joint frequency band optimization and classification fusion on multiple time windows to effectively utilize the signals of all time period within the MI task. Raw EEG data are first segmented into multiple subtime windows using a sliding window approach. Then, a set of overlapping bandpass filters is performed on each time window to generate a set of overlapping subbands, and common spatial pattern is used for feature extraction at each subband. Joint frequency band optimization is conducted on multiple time windows using a joint sparse optimization model. Fuzzy integral is used to fuse each time window after joint optimization. RESULTS: The proposed TFSOFF is validated on two public EEG datasets and compared with several other competing methods. Experimental results show that the proposed TFSOFF can effectively extract MI related features of all time period EEG signals within the MI task and helps improving the classification performance of MI. COMPARISON WITH EXISTING METHODS: The proposed TFSOFF exhibits superior performance in comparison with several competing methods. CONCLUSIONS: The proposed method is a suitable method for improving the performance of MI-based BCIs.

20.
Nanoscale ; 12(16): 8836-8846, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32255140

RESUMO

We demonstrate multi-wavelength light emission from InGaN nanowires (NWs) monolithically grown on pyramid-textured Si(100) substrates by plasma-assisted molecular beam epitaxy (MBE) under stationary conditions. Taking advantage of the highly unidirectional source material beam fluxes, the In content of the NWs is tuned on the different pyramid facets due to varied incidence angle. This is confirmed by distinct NW morphologies observed by scanning electron microscopy (SEM) and by energy-dispersive X-ray (EDX) element mapping. Photoluminescence and cathodoluminescence (CL) reveal multiple lines originating from InGaN NWs on the different pyramid facets. The anomalous temperature dependence of the emission wavelength results from carrier redistribution between localized or confined states, spontaneously formed within the NWs due to composition fluctuations, verified by high-resolution EDX elemental analysis. First-principles calculations show that the pyramid facet edges act as a barrier for atom migration and enhance atom incorporation. This leads to uniform composition within the facets for not too high a growth temperature, consistent with the SEM, EDX and CL results. At elevated temperature, InGaN decomposition and In desorption are enhanced on facets with low growth rate, accompanied by Ga inter-facet migration, leading to non-uniform composition over the Ga migration length which is deduced to be around 580 nm. Our study presents a method for the fabrication of multi-wavelength light sources by highly unidirectional MBE on textured Si substrates towards color temperature-tunable solid-state lighting and RGB light-emitting diode displays.

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