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1.
Carbohydr Polym ; 227: 115323, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31590841

RESUMO

Bacterial nanocellulose (BNC) has many advantages over plant cellulose, which make it widely used in many fields, especially in the food industry. In this study, three strains including BCA263, BCC529, and P1 were selected for characteristics analysis of BNCs under static and agitated culture conditions. The BNCs produced under static culture condition were in the shape of uniform membrane, while BNCs produced under agitated culture were in form of small agglomerates and fragments. BCA263 and BCC529 strains were more suitable for static culture, while P1 strain was more suitable for agitated culture. BNCs produced under static culture condition exhibited higher crystallinity, stronger tensile strength, denser network structure, higher temperature resistance and good flame retardancy; while BNCs produced under agitated culture condition exhibited larger porous and lower crystallinity. Furthermore, BNCs produced under agitated culture condition were more suitable as a stabilizer of coffee milk beverage.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31600885

RESUMO

The monitoring-blind area exists in the industrial park because of private interest and limited administrative power. As the atmospheric quality in the blind area impacts the environment management seriously, the prediction and inference of the blind area is explored in this paper. Firstly, the fusion network framework was designed for the solution of "Circumjacent Monitoring-Blind Area Inference". In the fusion network, the nonlinear autoregressive network was set up for the time series prediction of circumjacent points, and the full connection layer was built for the nonlinear relation fitting of multiple points. Secondly, the physical structure and learning method was studied for the sub-elements in the fusion network. Thirdly, the spatio-temporal prediction algorithm was proposed based on the network for the blind area monitoring problem. Finally, the experiment was conducted with the practical monitoring data in an industrial park in Hebei Province, China. The results show that the solution is feasible for the blind area analysis in the view of spatial and temporal dimensions.

3.
J Integr Neurosci ; 18(3): 277-283, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31601076

RESUMO

Rats were divided into six groups: sham/control , Dl-3-n-butylphthalide, P1 (low phenytoin, 100 mg/kg), P2 (high phenytoin, 200 mg/kg), NP1 (Dl-3-n-butylphthalide 80 mg/kg, phenytoin 100 mg/kg), NP2 (Dl-3-n-butylphthalide 80 mg/kg, phenytoin 200 mg/kg). Hematoxylin/eosin and Nissl staining showed that, compared to the sham/control group, the Dl-3-n-butylphthalide group had no obvious hippocampal and cerebellar neuron loss, but there was a significant neuron loss in the P1 and P2 groups (P < 0.05), which was more obvious in the P2 group (P < 0.05). The positive expression of Bax and Bcl-2 proteins in hippocampal and cerebellar neurons was not significantly different between sham and Dl-3-n-butylphthalide groups; however, compared to sham, Bax expression was significantly increased and Bcl-2 was significantly decreased in the hippocampal and cerebellar neurons of rats in both P1 and P2 groups (P < 0.05), being more obvious in the P2 group (P < 0.05). Furthermore, the administration of Dl-3-n-butylphthalide attenuated the deleterious effects of phenytoin (P < 0.05). Our results indicate that phenytoin causes apoptosis of hippocampal and cerebellar neurons in rats in a dose-dependent manner, with the effect of a higher dose being more obvious, whereas, Dl-3-n-butylphthalide inhibits the phenytoin-induced apoptosis of neurons and has a neuroprotective role.

4.
Mar Pollut Bull ; 145: 370-376, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31590799

RESUMO

In the present study, 13 endocrine disrupting compounds (EDCs) and their transformation products (TPs) were monitored in Jiulong River and its estuary, China in different seasons. The analytes included antimicrobials [triclosan (TCS) and triclocarbon (TCC)]; estrogens [estrone (E1), estradiol (E2), estriol (E3) and ethinylestradiol (EE2)]; alkylphenol ethoxylates [4-n-nonylphenol (NP) and 4-n-octylphenol (OP)] and the TPs [methyl triclosan (MeTCS), carbanilide (NCC), dichlorocarbanilide, 4-hydroxy estrone (4-OH E1) and 4-hydroxy estradiol (4-OH E2)]. A significant seasonal variation was observed for most EDCs. Approximately, 79% of the total E2 residues were detected in the normal season in comparison with the wet season to indicate recalcitrant behavior of E2 during the normal season. Risk assessment revealed that E2 was most potent among the EDCs to cause highest risk to both vertebrate and invertebrate aquatic species, whereas, E1, EE2, MeTCS and TCS also showed relatively high risk for some surface water aquatic species.

6.
Neurol Res ; : 1-9, 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31584350

RESUMO

Objectives: To investigate the thrombolysis with recombinant human prourokinase (rhPro-UK) on thromboembolic stroke in rats at different therapeutic time windows (TTW). Methods: Rats were subjected to embolic middle cerebral artery occlusion. RhPro-UK and positive control drugs rt-PA,UK were administered 3 h, 4.5 h, 6 h after inducing thromboem-bolic stroke. Neurological deficit scoring (NDS) was evaluated at 6 h and 24 h after the treatment. The lesion volume in cerebral hemispheres was measured by MRI scanning machine after 6 h of thrombolysis, and the infarct volume was measured by TTC stain, together with hemorrhagic volume quantified by a spectrophotometric assay after 24 h of thrombolysis. Results: RhPro-UK 10, 20 × 104 U/kg significantly improved the NDS after cerebral thromboembolism in rats at 3 h, 4.5 h TTW, and at the 6 h TTW, the NDS was improved by 28.0% (P = 0.0690) and 29.2% (P = 0.0927) at 6 h and 24 h after rhPro-UK 20 ×104 U/kg administration, respectively. RhPro-UK 10, 20 × 104 U/kg significantly reduced the brain lesions measured by MRI at 3 h and 4.5 h TTW. RhPro-UK 10, 20 × 104 U/kg significantly reduced the cerebral infarction measured by TTC at 3 h, 4.5 h TTW. There was no increase in cerebral hemorrhage compared with untreated group after rhPro-UK administration. Conclusions: RhPro-UK had an obvious therapeutic effect on ischemic stroke caused by thrombosis, and could be started within 4.5 h TTW with less side effects of cerebral hemorrhage than that of UK.

7.
Environ Pollut ; 255(Pt 2): 113256, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31563783

RESUMO

The presence of pesticide residues in fresh fruits and vegetables poses a serious threat to human health. Brassinosteroids (BRs) can reduce pesticide residues in plants, but the underlying mechanisms still remain unclear. Here, we identified a tomato glutaredoxin gene GRXS25 which was induced by 24-epibrassinolide (EBR) and chlorothalonil (CHT) in a way dependent on apoplastic reactive oxygen species (ROS). Silencing of GRXS25 in tomato abolished EBR-induced glutathione S-transferases (GSTs) gene expression and activity, leading to an increased CHT residue. Yeast two-hybrid and bimolecular fluorescence complementation assays showed protein-protein interaction between GRXS25 and a transcription factor TGA2. Electrophoretic mobility shift and chromatin immunoprecipitation assays indicated that TGA2 factor bound to the TGACG-motif in the GST3 promoter. While silencing of TGA2 strongly compromised, overexpression of TGA2 enhanced expression of GST genes and CHT residue metabolism. Our results suggest that BR-induced apoplastic ROS trigger metabolism of pesticide residue in tomato plants through activating TGA2 factor via GRXS25-dependent posttranslational redox modification. Activation of plant detoxification through physiological approaches has potential implication in improving the food safety of agricultural products.

8.
Res Aging ; : 164027519876095, 2019 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-31542998

RESUMO

The present study aimed to examine the association between community social capital and positive caregiving experiences among adult-children caregivers of disabled older adults in urban China. Data for this study were derived from the 2016 wave of the Longitudinal Study on Family Caregivers for Frail Older Adults Aged 75 or Above in Shanghai. The final analysis featured 440 disabled older adult and adult-children caregiver dyads. Multiple indicators and multiple causes modeling was used to test the proposed model from a structural equation modeling perspective. Provision of support to others was significantly associated with self-affirmation. Citizenship activity was significantly associated with life enrichment. Support of units (i.e., employers) was significantly associated with self-affirmation and life enrichment. The findings support the integration of the stress process model and social capital theory and highlight the important role of community social capital in enhancing the subdimensions of positive caregiving experiences. Policy and intervention implications are discussed.

9.
Opt Express ; 27(18): 25943-25952, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31510456

RESUMO

High performance InGaN-based laser diodes (LDs) monolithically grown on Si is fundamentally interesting and highly desirable for photonics integration on Si platform. Suppression of point defects is of crucial importance to improve the device performance of InGaN-based LDs grown on Si. This work presents a detailed study on the impact of point defects, such as carbon (C) impurities and gallium vacancies (VGa), on the device characteristics of InGaN-based LDs grown on Si. By suppressing the VGa-related defect within the waveguide layers, reducing the thermal degradation of InGaN-based quantum wells, and controlling the C impurity concentrations within the thick p-type cladding layers, the as-fabricated InGaN-based LDs grown on Si exhibited a significantly reduced threshold current density of 2.25 kA/cm2 and an operation voltage of 4.7 V.

10.
J Biol Inorg Chem ; 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31515622

RESUMO

Hydrogen polysulfides (H2Sn, n > 1), as the oxidized forms of H2S, have attracted increasing attention these years due to their involvement in signaling transduction and cytoprotective processes. It is necessary to detect H2Sn in living systems for the study of their functions. In this work, we report a BODIPY-based near-infrared emitting fluorescence probe NIR-PHS1, with "turn-on" response, rapid response rate (within 10 min), outstanding selectivity and excellent sensitivity (detection limit = 12 nM) response towards H2Sn. The probe was successfully applied to the visualizing of endogenous H2Sn in living cells. Moreover, it can be used for near-infrared in vivo imaging of H2Sn in living mice. Therefore, NIR-PHS1 could be a potential imaging tool to study the biological roles of H2Sn in living systems.

11.
Artigo em Inglês | MEDLINE | ID: mdl-31498508

RESUMO

This study investigated the effect of Lactobacillus plantarum strain 299v on gut health in suckling piglets. Sixty newborn piglets were assigned to control and probiotic treatments, with three litters per treatment (ten piglets/litter). From days 1 to 20 of life, piglets were orally administered a placebo of 0.1% peptone or 1.0 ×  1010  CFU L. plantarum 299v daily. Six piglets per treatment were sacrificed on day 20, and intestinal tissues (including duodenum, jejunum, ileum and colon) and the intestinal contents from colon segments were collected. The results demonstrated that piglets treated with L. plantarum 299v had a lower diarrhoea incidence than the controls. L. plantarum 299v administration significantly increased the ratio of the villus height to the crypt depth in the jejunum and ileum, as well as the mRNA expression of jejunal occludin and ileal zonula occludens 1 (ZO-1). The L. plantarum treatment also increased the mRNA abundance of porcine ß-defensin 2 (pBD2) and pBD3 in the jejunum and ileum and of toll-like receptors (TLRs), such as TLR2, TLR4, TLR6 and TLR9 in the ileum, and significantly upregulated the mRNA abundances of ileal pBD1 and colonic TLR4. Additionally, the L. plantarum 299v treatment significantly changed the structure of the colonic microbiota, as evidenced by the obvious increases in the relative abundances of the phyla Firmicutes and Actinobacteria and of the genus Lactobacillus. Our findings indicate that L. plantarum 299v facilitates the gut health of suckling piglets, probably by improving the intestinal morphology and intestinal barrier function and by modifying the structure of the gut microbiota.

12.
Toxicol Lett ; 316: 73-84, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31513886

RESUMO

In the liver microenvironment, interactions among diverse types of hepatic cells are involved in liver fibrosis. In fibrotic tissues, exosomes act as transporters in intercellular communication. Long non-coding RNAs (lncRNAs) are involved in the activation of hepatic stellate cells (HSCs), which are participants in liver fibrosis. However, the functions of exosomal lncRNAs in liver fibrosis induced by arsenite are undefined. The purposes of the present study were (a) to determine if lncRNAs secreted from human hepatic (L-02) cells exposed to arsenite are shuttled to hepatic stellate LX-2 cells and (b) to establish their effects on LX-2 cells. In mice, MALAT1 was overexpressed in the progression of liver fibrosis induced by arsenite as well as in L-02 cells exposed to arsenite. Co-cultures with arsenite-treated L-02 cells induced the activation of LX-2 cells and overexpression of MALAT1. Arsenite-treated L-02 cells transported MALAT1 into LX-2 cells. Downregulation of MALAT1, which reduced the MALAT1 levels in exosomes derived from arsenite-treated L-02 cells, inhibited the activation of LX-2 cells. Additionally, exosomal MALAT1 derived from arsenite-treated L-02 cells promoted the activation of LX-2 cells via microRNA-26b regulation of COL1A2. Furthermore, circulating exosomal MALAT1 was up-regulated in people exposed to arsenite. In sum, exosomes derived from arsenite-treated hepatic cells transferred MALAT1 to HSCs, which induced their activation. These findings support the concept that, during liver fibrosis induced by arsenite, exosomal lncRNAs are involved in cell-cell communication.

13.
Anal Biochem ; 587: 113460, 2019 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-31563442

RESUMO

Betulin, as a new type of natural food preservative, is widely used in various kinds of meat products. However, its detailed mechanism of action and metabolism have not been clarified. In this study, for further gain insight of the mechanism of betulin as a preservative, an efficient method has been applied for measuring the antioxidant capacity of betulin, based on the absorbance of the DPPH• and ABTS• radical cation. When the concentration of betulin was more than 2.0 mg/mL, the scavenging rate of ABTS and DPPH radical reached over 90%, which was equivalent to the antioxidant capacity of Trolox. It is indicated that betulin has significant DPPH and ABTS free radical scavenging ability. This should be one of the important mechanisms for betulin as a preservative. A sensitive method using UHPLC-Q-TOF-MS/MS was established to determine the metabolite profile in vivo and in vitro of betulin. 32 phase I and 2 phase II metabolites were structurally characterized. This study will provide theoretical support for the safety and effectiveness of betulin in the field of preservatives and provide theoretical basis for the further study of betulin and the other natural preservatives. This research also contributes to the development of the food industry.

14.
Surg Oncol ; 31: 8-13, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31446304

RESUMO

BACKGROUND: The standard prognostic system for malignant ovarian germ cell tumors (MOGCT) has not yet been established and the scope of surgery was also controversial. Mixed ovarian malignant germ cell tumor (mGCT) is a rare histological type of MOGCT with higher malignant degree than other types. The aim of the present study was to investigate the clinical features and prognosis of mGCT, and prognostic factors for MOGCT to provide guidance for future treatment. METHODS: Retrospective analysis was carried out on 137 patients, who were admitted from 1991 to 2014. Survival curves were constructed using Kaplan-Meier method and were compared with the log-rank test across various pathological types and different stages. Multivariate survival analysis was performed using Cox's proportional hazards model. RESULTS: There were 29 dysgerminomas (DG), 3 embryonal carcinomas (EC), 43 immature teratomas (IT), 48 yolk sac tumors (YST) and 14 mixed germ cell tumors (mGCT). The most common type of mGCT is YST (85.7%), followed by IT (64.3%), EC (28.6%), and DG (21.4%). The respective 5-year OS rates were 100% in DG, 100% in EC, 92.5% in IT, 54.5% in YST and 66.7% in mGCT, while the corresponding 5-year PFS rate were 89.7% in DG, 100% in EC, 85.1% in IT, 55.9% in YST and 60% in mGCT. FIGO stage Ⅲ-Ⅳ, certain pathological types (Yolk sac tumors and mGCT) and the number of postoperative chemotherapy courses were independently unfavorable prognostic in a multivariate model that included age, Admission decade, fertility-sparing surgery, and comprehensive staging surgery. CONCLUSIONS: Fertility-sparing surgery and incomplete surgical staging did not affect the prognosis. It might be safe to preserve fertility and shrink the scope of the surgical procedures in MOGCT patients regardless of stage or pathology. However, prospective randomized controlled trials were needed for further evaluation.

15.
BMC Plant Biol ; 19(1): 351, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31412785

RESUMO

BACKGROUND: Rubisco activase (RCA) regulates the activity of Rubisco and is a key enzyme of photosynthesis. RCA expression was widely reported to affect plant photosynthesis and crop yield, but the molecular basis of natural variation in RCA expression in a wide range of maize materials has not been fully elucidated. RESULTS: In this study, correlation analysis in approximately 200 maize inbred lines revealed a significantly positive correlation between the expression of maize RCA gene ZmRCAß and grain yield. A genome-wide association study revealed both cis-expression quantitative trait loci (cis-eQTLs) and trans-eQTLs underlying the expression of ZmRCAß, with the latter playing a more important role. Further allele mining and genetic transformation analysis showed that a 2-bp insertion and a 14-bp insertion in the promoter of ZmRCAß conferred increased gene expression. Because rice is reported to have higher RCA gene expression than does maize, we subsequently compared the genetic factors underlying RCA gene expression between maize and rice. The promoter activity of the rice RCA gene was shown to be stronger than that of the maize RCA gene, suggesting that replacing the maize RCA gene promoter with that of the rice RCA gene would improve the expression of RCA in maize. CONCLUSION: Our results revealed two DNA polymorphisms regulating maize RCA gene ZmRCAß expression, and the RCA gene promoter activity of rice was stronger than that of maize. This work increased understanding of the genetic mechanism that underlies RCA gene expression and identify new targets for both genetic engineering and selection for maize yield improvement.


Assuntos
Oryza/genética , Fotossíntese/genética , Proteínas de Plantas/genética , Zea mays/genética , Expressão Gênica , Regulação da Expressão Gênica de Plantas , Estudo de Associação Genômica Ampla , Oryza/metabolismo , Oryza/fisiologia , Folhas de Planta , Proteínas de Plantas/metabolismo , Proteínas de Plantas/fisiologia , Regiões Promotoras Genéticas , Locos de Características Quantitativas , Ribulose-Bifosfato Carboxilase , Zea mays/metabolismo , Zea mays/fisiologia
16.
Medicine (Baltimore) ; 98(35): e17008, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31464958

RESUMO

Urinary kallidinogenase may assist recovery acute ischemic stroke. This study evaluated the effect of urinary kallidinogenase on National Institute of Health Stroke Scale (NIHSS) score, modified Rankin scale (mRS) score, and fasting glucose levels in patients with acute ischemic stroke (AIS) combined with diabetes mellitus and impaired fasting glucose.Patients with AIS and abnormal glucose metabolism were enrolled in this prospective cohort study and divided into 2 groups. The human urinary kallidinogenase (HUK) group were treated with urinary kallidinogenase and standard treatment; the control group received standard treatment. NIHSS scores, mRS scores, and fasting blood glucose were evaluated and compared.A total of 113 patients were included: 58 in the HUK group and 55 in the control group. NIHSS scores decreased with treatment in both groups (time effect P < .05), but were lower in the HUK group (main effect P = .026). The mRS score decreased in both groups from 10 until 90 days after treatment (time effect P < .05); the 2 groups were similar (main effect, P = .130). Blood glucose levels decreased in both groups 10 days after treatment (time effect, P < .05), but there was no significant treatment effect (main effect, P = .635). Multivariate analysis showed blood uric acid >420 µmol/L (odds ratio [OR]: 0.053, 95% confidence interval [CI]: 0.008-0.350; P = .002) and application of HUK (OR: 0.217, 95% CI: 0.049-0.954; P = .043) were associated with 90% NIHSS recovery. Baseline NIHSS score was independently associated with poor curative effect.Urinary kallidinogenase with conventional therapy significantly improved NIHSS scores in patients with AIS. Urinary kallidinogenase also showed a trend toward lower fasting blood glucose levels, although the level did not reach significance.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Acidente Vascular Cerebral/tratamento farmacológico , Calicreínas Teciduais/uso terapêutico , Adulto , Idoso , Glicemia/efeitos dos fármacos , Isquemia Encefálica/etiologia , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/fisiopatologia , Feminino , Intolerância à Glucose/epidemiologia , Intolerância à Glucose/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Estudos Prospectivos , Índice de Gravidade de Doença , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/epidemiologia
17.
IUBMB Life ; 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31381266

RESUMO

Malignant hyperthermia is a pharmacogenetic disorder, which is an uncommon but frequently fatal intricacy of inhalation anesthesia in man. It causes a quick rise in body temperature to highly irreversible levels, which causes death in around three of four cases. The trigger anesthetics cause an anomalous, continued ascent in myoplasmic calcium levels. Possible mechanisms by which continuous release of sodium, calcium from skeletal muscle plasma membrane and sarcoplasmic reticulum stores respectively can produce the profound hyperthermia are discussed.

18.
19.
ACS Appl Mater Interfaces ; 11(34): 31078-31086, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31381286

RESUMO

Based on exciplexes as hosts, the monochromatic organic light-emitting diodes (OLEDs) have achieved high power and external quantum efficiencies. However, the high-quality white OLEDs (WOLEDs) with high color rendering index (CRI) have the unsatisfactory efficiencies at high luminance, particularly in terms of power efficiency (PE), resulting in high energy consumption. Here, a new design concept using multiple exciplexes as hosts to match different phosphors has been demonstrated to develop high-performance WOLEDs. It can be seen that the resulting WOLEDs work at a low turn-on voltage of 2.3 V and exhibit the large forward-viewing PE and external quantum efficiency (EQE) of 79 lm W-1 and 22.5%, respectively, without light out-coupling techniques. Significantly, the PE and EQE still remain 48.0 lm W-1 and 21.4% at 1000 cd m-2, showing extremely low efficiency roll-off. The CRI is as high as 81. The keys to success are the selection of the different exciplex hosts matched to different phosphors and the reasonable arrangement of emissive layers, which are beneficial to regulate the exciton distribution and reduce the energy losses.

20.
Cell Rep ; 28(5): 1182-1194.e4, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31365863

RESUMO

Brain state fluctuations modulate sensory processing, but the factors governing state-dependent neural activity remain unclear. Here, we tracked the dynamics of cortical extracellular K+ concentrations ([K+]o) during awake state transitions and manipulated [K+]o in slices, during visual processing, and during skilled motor execution. When mice transitioned from quiescence to locomotion, [K+]o increased by 0.6-1.0 mM in all cortical areas analyzed, and this preceded locomotion by 1 s. Emulating the state-dependent [K+]o increase in cortical slices caused neuronal depolarization and enhanced input-output transformation. In vivo, locomotion increased the gain of visually evoked responses in layer 2/3 of visual cortex; this effect was recreated by imposing a [K+]o increase. Elevating [K+]o in the motor cortex increased movement-induced neuronal spiking in layer 5 and improved motor performance. Thus, [K+]o increases in a cortex-wide state-dependent manner, and this [K+]o increase affects both sensory and motor processing through the dynamic modulation of neural activity.

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