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1.
Exp Cell Res ; : 111613, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31494095

RESUMO

The lipotoxicity is considered as one of the risk for diabetes. Here we report C-type lectin domain family 11, member A (Clec11a) as a new regulator in islet playing a protective role in lipotoxicity induced dysfunction. Islet transcriptome sequencing was performed using the high-fat diet induced obesity (DIO) mice model. We found a significant decrease of Clec11a expression in islets of DIO mice compared to normal control mice, which was further confirmed by real-time PCR. Immunostaining demonstrated the localization of the Clec11a protein in mouse islets. Administration of recombinant human Clec11a (rClec11a) protein promoted the proliferation of islet cells and rescued the inhibition of fatty acid on cell proliferation, which involved the activation of Erk signaling pathway. We also found that the rClec11a altered the expression of genes involved in lipid metabolism.

2.
Genomics ; 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31401233

RESUMO

Lineage-specific genes (LSGs) are a set of genes in a given taxon without significant sequence similarity to genes and intergenic sequences of other taxa and are functional. The tribe Triticeae mainly includes species of different ploidy levels, such as staple food crops wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.). This study is aimed at mining and characterizing the Triticeae-specific genes (TSGs) using expressed sequence data of wheat. A total of 3812 TSGs was identified and they were generally characterized by smaller size, fewer exons, shorter open reading frames and lower expression levels. Most TSGs were expressed with tissue preference and many of them were predominantly expressed in reproduction related tissues, especially in young stamen. Nearly one third of the TSGs were stress-responsive and inducible under abiotic and/or biotic stresses. A co-expression-based annotation supported the relevance of some TSGs with reproduction and stress responses, indicating their potential economic importance.

3.
J Affect Disord ; 257: 684-690, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31377605

RESUMO

BACKGROUND: Mental health has become a new focus of public health related to migrants in recent years. There are many contradictions in previous studies on the mental health status of migrant children in China. METHODS: PubMed, OVID, ERIC, Web of Knowledge, CNKI, Wan Fang and Chongqing VIP were searched on August 16, 2018. The data were analyzed using SMD and random effect model in Comprehensive Meta-Analysis software. RESULTS: We included 11 studies involving 4621 migrant children and 5076 urban children. The mental health of migrant children was worse than that of urban children, as evidenced by total score of Mental Health Test (Standardized Mean Difference, SMD = 0.36, 95% CI 0.21 to 0.59) and seven out eight sub-scales of Mental Health Test (SMD, ranging from 0.24 to 0.37). The results were robust to sensitivity analysis. CONCLUSION: Our study supports the notion that compared with urban counterparts, migrant children had more mental health problems with less public services. Future research should focus on how to improve mental health of migrant children.

4.
Carbohydr Polym ; 223: 115069, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31426996

RESUMO

Resistant starch (RS) acylated with propionate groups is of particular interest in terms of their capacity to deliver specific short-chain fatty acids (SCFAs) to the colon with health benefits. In the present study, we fabricated propionylated high-amylose maize starches with different degrees of substitution (DS), and monitored the in vitro human fecal fermentation profiles. Propionylated modification did not change the slow gas production properties of high-amylose maize starch throughout the whole fermentation period. The final concentration of propionate (13.68-21.10 mM) produced by propionylated starch fermentation enhanced gradually with increase of DS value, resulting from the release of introduced propionyl groups. Certain beneficial gut microbiota such as Roseburia, and Blautia were obviously promoted, suggesting that propionylated starch could regulate the composition of gut microbiota. The results may facilitate the design and manufacture of functional food products with the aim of improving colonic health.

6.
J Physiol Sci ; 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31392590

RESUMO

Exercise has an effect on the reduction of myocardial fibrosis in diabetic rats as previously reported, in which oxidative stress and the TGF-ß1/Smad signaling pathway may play key roles. There is little direct experimental evidence that exercise alleviates myocardial fibrosis in type 2 diabetes mellitus (T2DM). Here we established a type 2 diabetic model by using streptozotocin and a high-fat diet. Rats were divided into groups of normal control (NC), T2DM and T2DM plus exercise (T2DME). The T2DME group received further treadmill training at moderate intensity for 8 weeks. Histological and biochemical methods were used to detect the benefits of exercise to T2DM. Results showed that the weight of rats in the T2DM group dropped dramatically, along with significant increases in blood glucose, myocardial fibrosis and oxidative stress, associated with upregulated expression of factors of myocardial fibrosis, except Smad7. Exercise largely reversed T2DM-induced alterations in factors of myocardial fibrosis, including suppressing expression of MMP-2, CTGF, TGF-ß1, p-Smad2 and p-Smad3, and increased expression of TIMP-1 and Smad7. Therefore, exercise might be considered an alternative therapeutic remedy for diabetic cardiomyopathy.

7.
Pathog Dis ; 77(4)2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31348491

RESUMO

Pseudomonas aeruginosa is an important opportunistic pathogen normally associated with increasing morbidity and mortality of immunocompromised hosts with respiratory infections. The phenotypic and genetic features of P. aeruginosa from patients with chronic obstructive pulmonary disease (COPD) remain poorly understood. By using the sputum samples of 25 hospitalized COPD patients from the affiliated hospital of Southwest Medical University (China), we identified a P. aeruginosa isolate, COP2, which showed multiple antibiotic resistance and enhanced Pseudomonas quinolone signal (PQS) production but decreased motility, biofilm formation and virulence compared with the model strain PAO1. Importantly, COP2 harbored a substantial amount of mutations that might influence the functions of 1771 genes in the genome and the evolutionary status of this isolate was clearly distinct from the PAO1 lineage. Accordingly, COP2 had a discrepant transcriptional pattern relating to flagellar assembly, antibiotic resistance, biofilm and PQS production, and can increase the capacities of compound degradation in response to resource/space stresses. Therefore, the identification of COP2 in this study provides preliminary information regarding the genetic features and survival strategy of P. aeruginosa in colonizing COPD lungs and lays the foundations for further understanding of the pathogenic mechanisms of pseudomonal infections.

8.
Org Lett ; 21(16): 6264-6269, 2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31343889

RESUMO

Efficient procedures for the selective α- or ß-functionalization of α-diazoketones with aromatic amides were developed by using a cobalt catalyst under ligand-free conditions. Normal α-functionalization of α-diazoketones was achieved via C(sp2)-H bond functionalization of aromatic amides in the presence of Co(acac)2/TBHP. Interestingly, ß-functionalization of α-diazoketones was realized with a Co(OAc)2/AgOAc catalyst system. Further intramolecular cyclization afforded the desired isoindolinones in good to excellent yields.

9.
Plant Sci ; 285: 141-150, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31203879

RESUMO

Plant tissue brittleness is related to cellular structure and lodging. MED0031 is a mutant identified previously from ethyl methane sulfonate treatment of diploid wheat accession TA2726, showing brittleness in both stem and leaf. In microscopic and histological observations, the mutant was found to have less large vascular bundles per unit area, a thinner sclerenchyma cell wall, and a broader parenchyma, compared with the wild type. The mutated gene, TmBr1, was mapped to a 0.056 cM interval on chromosome 5Am. This gene was cloned using a MapRseq approach that searched the candidate gene through combination of the prior target gene mapping information with SNP calling and discovery of differentially expressed genes from RNA_seq data of the wild type and a BC3F2 bulk showing the mutant phenotype. TmBr1 encodes a COBL protein and a nonsense mutation within the region coding for the conserved COBRA domain caused premature translation termination. Introduction of TmBr1 to Arabidopsis AtCOBL4 mutant rescued the phenotype, demonstrating their functional conservation. Apart from the effect on cellulose content, the TmBr1 mutation might modulate synthesis of noncellulosic polysaccharide pectin as well. Application of the MapRseq approach to isolation of genes present in recombination cold spots and complicated genomes was discussed.


Assuntos
Clonagem Molecular/métodos , Genes de Plantas/genética , Triticum/genética , Parede Celular/metabolismo , Celulose/metabolismo , Mapeamento Cromossômico , Genes de Plantas/fisiologia , Lignina/metabolismo , Microscopia Eletrônica de Varredura , Pectinas/metabolismo , Filogenia , Reação em Cadeia da Polimerase em Tempo Real , Triticum/anatomia & histologia , Triticum/fisiologia
10.
Carbohydr Polym ; 220: 211-218, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31196542

RESUMO

An efficient and one step production of acetylated and esterified chitin nanocrystals (CNCs) was successfully achieved using choline chloride-zinc chloride deep-eutectic solvent (ChCl-ZnCl2 DES). In this method, ChCl-ZnCl2 DES with a mole ratio of 1:2, was used for the esterification and O-acetylation of chitin at 90 °C for 3 h and 6 h. This strategy consisted in using ChCl-ZnCl2 DES as a green and non-volatile solvent for chitin under heterogeneous condition that, upon addition of acetic anhydride or acetic acid, simultaneous acetylation or esterification and hydrolysis occurred. The DES act as an efficient catalysis of the functional reaction. The acetylation and hydrolysis proceeded efficiently and the yield of partial acetylated CNCs was ca. 61.6% with DS (degree of substitution) of 0.23 under the optimized conditions. Acetic acid was used to substituted acid anhydride to produce CNCs. The yield of acetic acid induced CNCs was ca. 62.0% with higher DS of 0.34. A thorough investigation of the physicochemical characteristics changes of chitin pointed out that the main skeletal structure of obtained CNCs was intact. The thermal stability of CNCs decreased after treated by ChCl/ZnCl2. In addition, thermal stability of CNCs functionalized with acetic acid is lower than the ones functionalized with acetic anhydride. DES showed low expenditure and toxicity. This approach provides a novel method for production of functional chitin nanocrystals.

11.
Carbohydr Polym ; 219: 181-190, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31151515

RESUMO

Water-soluble fraction (WSF), CDTA-soluble fraction (CSF), sodium carbonate-soluble fraction (SSF), loosely-bonding KOH-soluble fractions (LKF) and tightly-bonding KOH-soluble fractions (TKF) were sequentially extracted from tomato cell wall polysaccharides. Physicochemical properties and functional bioactivities of these different bonding state tomato fruit polysaccharides (DBTP) were investigated. WSF, CSF and SSF were identified as pectic polysaccharides, while LKF and TKF were identified as hemicellulose. WSF, possessing plenty of galacturonic acids, was considered as an aggregative of linear homogalacturonan with extremely high molecular weight. CSF and SSF, rich in neutral sugars side chains, contained abundant rhamnogalacturonan regions. These polysaccharides exhibited distinct surface morphology and special FTIR spectrums. Thermal analysis manifested that LKF and TKF exhibited higher thermal stability. WSF and SSF showed higher apparent viscosity and elasticity. Assays for functional bioactivities suggested that CSF and SSF displayed stronger antioxidant activities, while CSF, SSF and TKF exhibited higher hypolipidemic activities.

12.
Nat Genet ; 51(7): 1106-1112, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31182810

RESUMO

Head or ear blight, mainly caused by Fusarium species, can devastate almost all staple cereal crops (particularly wheat), resulting in great economic loss and imposing health threats on both human beings and livestock1-3. However, achievement in breeding for highly resistant cultivars is still not satisfactory. Here, we isolated the major-effect wheat quantitative trait locus, Qfhs.njau-3B, which confers head blight resistance, and showed that it is the same as the previously designated Fhb1. Fhb1 results from a rare deletion involving the 3' exon of the histidine-rich calcium-binding-protein gene on chromosome 3BS. Both wheat and Arabidopsis transformed with the Fhb1 sequence showed enhanced resistance to Fusarium graminearum spread. The translation products of this gene's homologs among plants are well conserved and might be essential for plant growth and development. Fhb1 could be useful not only for curbing Fusarium head blight in grain crops but also for improving other plants vulnerable to Fusarium species.

13.
Org Lett ; 21(13): 5310-5314, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31240938

RESUMO

The synthesis of 1,1-dicarbonyl sulfoxonium ylides by palladium-catalyzed carbonylation of aryl halides or triflates with α-carbonyl sulfoxonium ylides has been developed for the first time. This method provides a general approach to synthetically useful 1,1-dicarbonyl sulfoxonium ylides in high efficiency. The protocol displays a wide substrate scope, showing that the resulting 1,1-dicarbonyl sulfoxonium ylides have been converted into the corresponding 1,3-dicarbonyl compounds.

14.
Evid Based Ment Health ; 22(3): 111-117, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31221690

RESUMO

BACKGROUND: The comparative efficacy and tolerability of methylphenidate (MPH) and neurofeedback (NF) in individuals with attention-deficit/hyperactivity disorder (ADHD) remains uncertain. This study aimed to fill this gap by means of a systematic review/meta-analysis. METHODS: PubMed, OVID, ERIC, Web of Science, ClinialTrials.gov and a set of Chinese databases were searched until 22 August 2018. Standardised mean differences (SMD) were pooled using comprehensive meta-analysis software. RESULTS: 18 randomised controlled trials (RCTs) were included (778 individuals with ADHD in the NF arm and 757 in the MPH group, respectively; 13 studies in Chinese, five in English). At the study first endpoint, MPH was significantly more efficacious than NF on ADHD core symptoms (ADHD symptoms combined: SMD=-0.578, 95% CI (-1.063 to -0.092)) and on two neuropsychological parameters (inattention:-0.959 (-1.711 to -0.208); inhibition:-0.469 (-0.872 to -0.066)). Dropouts were significantly lower in NF versus MPH (OR=0.412, 0.186 to 0.913). Results were robust to sensitivity analyses, with two important exceptions: removing Chinese studies and non-funded studies, no differences emerged between MPH and NF, although the number of studies was small. At the study follow-up, MPH was superior to NF in some outcomes, but results were inconsistent across raters. CONCLUSIONS: Due to the risk of bias of included studies, the results of the sensitivity analysis excluding Chinese and non-funded studies, and the mixed findings on at the follow-up endpoint, further high quality studies are needed to assess the comparative efficacy and acceptability of NF and MPH in individuals with ADHD. TRIAL REGISTRATION NUMBER: CRD42018090256.

15.
Nanoscale ; 11(21): 10203-10208, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31112198

RESUMO

Assembling two-dimensional (2D) nanomaterials into three-dimensional (3D) hierarchical structures with novel functions is challenging and has attracted considerable attention. However, it is quite difficult to obtain complex 3D architectures of 2D materials with a uniform and intact structure using traditional methods, such as hydrothermal/solvothermal methods and direct precipitation methods. Here, we use butterfly wing scales as bio-templates to prepare 3D hierarchical BiOCl/Au wing scales for plasmonic photocatalysis. The as-prepared materials exhibit excellent photodegradation of rhodamine B (RhB) under visible light. The degradation rates of BiOCl microspheres and BiOCl and BiOCl/Au butterfly wing scales are 48.8%, 72.6%, and 93.8%, respectively, within 20-min illumination at the same loading capacities. This excellent performance of BiOCl/Au is attributed to the coupling of enhanced carrier separation efficiency and the effect of localized surface plasmon resonance (LSPR) aroused by 3D metallic structures. This study provides a relatively facile method to obtain complex 3D constructure of 2D materials. It also demonstrates a nature-led route to prepare highly efficient plasmonic photocatalysts.

16.
Inorg Chem ; 58(11): 7480-7487, 2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31074626

RESUMO

With the help of modulator synthesis method, a mesoporous Zr-based metal-organic framework, [Zr6O4(OH)8(H2O)4(TADIBA)4]·24DMF·45H2O (DMF = N, N-dimethylformamide, H2TADIBA = 4,4'-(2 H-1,2,4-triazole-3,5-diyl) dibenzoic acid), namely, JLU-MOF58, was successfully constructed. JLU-MOF58 having reo topology is constructed by the bent ligands with Lewis basic sites and 8-connected Zr6 clusters with Lewis and Brønsted acid sites. It not only possesses two types of mesoporous cages: octahedral and cuboctahedral (2.76 and 4.10 nm), with a pore volume of 1.76 cm3 g-1, but also displays excellent chemical stability in acid and base aqueous phase. Benefiting from the Brønsted and Lewis acid sites, Lewis basic sites, excellent chemical stability, and the mesoporous cages incorporated in the framework, JLU-MOF58 can be regarded as a remarkably efficient heterogeneous catalyst that exhibits excellent catalytic efficiency for CO2 conversion.

17.
Sensors (Basel) ; 19(8)2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31027269

RESUMO

The reliability of gas insulated switchgear (GIS) is very important for the safe operation of power systems. However, the research on potential faults of GIS is mainly focused on partial discharge, and the research on the intelligent detection technology of the mechanical state of GIS is very scarce. Based on the abnormal vibration signals generated by a GIS fault, a fault diagnosis method consisting of a frequency feature extraction method based on coherent function (CF) and a multi-layer classifier was developed in this paper. First, the Fourier transform was used to analyze the differences and consistency in the frequency spectrum of signals. Secondly, the frequency domain commonalities of the vibration signals were extracted by using CF, and the vibration characteristics were screened twice by using the correlation threshold and frequency threshold to further select the vibration features for diagnosis. Then, a multi-layer classifier composed of two one-class support vector machines (OCSVMs) and one support vector machine (SVM) was designed to classify the faults of GIS. Finally, the feasibility of the feature extraction method was verified by experiments, and compared with other classification methods, the stability and reliability of the proposed classifier were verified, which indicates that the fault diagnosis method promotes the development of an intelligent detection technology of the mechanical state in GIS.

18.
J Chin Med Assoc ; 82(4): 328-334, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30946211

RESUMO

BACKGROUND: The technology of using inertial measurement units (IMUs) to detect motions in different body segments has drawn enormous attention to research and industry. In our previous research, we have applied IMUs in evaluating and treating patients with vestibular hypofunction. Furthermore, according to the research, when a person's head rotates over 60° on either side in the horizontal plane, and desires to focus vision on any targets, then the function of gaze shift comes in to operation. Herein, we aimed to use IMUs to build up a system to evaluate vestibular ocular reflex (VOR) during gaze shifting maneuver. METHODS: In this study, we developed a platform, which combines the features of gaze shift and computerized dynamic visual acuity (cDVA), called the gaze shift DVA (gsDVA) platform. The gsDVA platform measures the orientations of the subject's head by IMU, and executed the evaluation according to the algorithm that was developed by us. Finally, we used the VICON system to validate the performance of gsDVA platform. RESULTS: The performance of the accuracy was 2.41° ± 1.08°, the maximal sensor error was within 4.25°, and highly correlated between our platform and VICON (p < 0.05, R = 0.99). The intraclass correlation coefficient (ICC) of between-day and within-day was 0.984 and 0.999, respectively. Furthermore, the platform not only executed the evaluation automatically but also recorded other information besides the head orientation, such as rotation speed, rotation time, reaction time, and visual acuity. CONCLUSION: In this study, we demonstrated the utility of vestibular evaluation, and this platform can help to clarify the relationship between gaze shift and VOR. This methodology is useful and can be applied efficiently to different disease groups for interactive evaluation and rehabilitation programs.

19.
Small ; 15(18): e1805308, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30938487

RESUMO

Assembling nanosized building blocks into macroscopic 3D complex structures is challenging. Here, nanosized metal and semiconductor building blocks with a variety of sizes and shapes (spheres, stars, and rods) are successfully assembled into a broad range of hierarchical (nanometer to micrometer) assemblies of functional materials in centimeter size using butterfly wings as templates. This is achieved by the introduction of steric hindrance to the assembly process, which compensates for attraction from the environmentally sensitive hydrogen bonds and prevents the aggregation of nanosized building blocks. Of these materials, Au nanostar assemblies show a superior enhancement in surface-enhanced Raman scattering (SERS) performance (rhodamine 6G, 1506 cm-1 ) under 532, 633, and 780 nm excitation-this is 3.1-4.4, 3.6-3.9, and 2.9-47.3 folds surpassing Au nanosphere assemblies and commercial SERS substrates (Q-SERS), respectively. This method provides a versatile route for the assembly of various nanosized building blocks into different 3D superstructures and for the construction of hybrid nanomaterials and nanocomposites.

20.
Am J Rhinol Allergy ; 33(2): 145-152, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30871345

RESUMO

BACKGROUND: Predominantly, 2 animal models are used for allergic rhinitis (AR), which are established by intraperitoneal (IP) injection plus local challenge and nasal-only delivery. The differences between these 2 models are not fully understood. Moreover, dose-response relationship to allergens remains unclear. METHODS: In this study, mice were sensitized by nasal drops (without adjuvant, once daily for 9 weeks) to set up a nasal-only delivery AR model. Five different doses of ovalbumin (OVA) nasal drops were served to explore the dose-response to allergens. Allergic symptoms, serum antibodies (IgE, IgG2a, and IgG1), spleen supernatant and nasal lavage fluid (NALF) cytokines (IL-4, IL-5, and IFN-r), and infiltrated eosinophils of the nasal mucosa were observed. RESULTS: The allergic symptoms, serum antibodies, cytokines, and infiltrated eosinophils were significantly higher in the high OVA concentration compared with those of the control group. Different OVA concentrations associated with the severity of allergy. Within a certain concentration range, OVA concentration positively related to the severity of symptoms, IgE antibody level, and Th2 bias. Meanwhile, serum antibodies (IgE and IgG1) and cytokines (IL-4, IL-5 in spleen and IL-4 in NALF) were significantly higher in the classical IP injection group than in the nasal drip groups. CONCLUSION: The IP injection model and the nasal-only delivery model are 2 typical models for AR that causes a different immune response. A positive dose-response relationship in the nasal-only delivery model is observed from 25 mg/mL to 0.025 mg/mL.


Assuntos
Alérgenos/administração & dosagem , Ovalbumina/administração & dosagem , Rinite Alérgica/imunologia , Administração Intranasal , Alérgenos/imunologia , Animais , Citocinas/imunologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Esquema de Medicação , Eosinófilos/patologia , Feminino , Imunoglobulina E/sangue , Injeções Intraperitoneais , Camundongos Endogâmicos BALB C , Líquido da Lavagem Nasal/imunologia , Mucosa Nasal/imunologia , Mucosa Nasal/patologia , Ovalbumina/imunologia , Rinite Alérgica/sangue
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