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1.
Waste Manag ; 103: 285-295, 2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31911375

RESUMO

Waste sorting at the source is a vital strategy of waste management and to improve urban sustainability. If the strategy is implemented by relying solely on publicity and civic awareness, the impact is less significant. Proactive measures, such as policy regulations, supervisory guidance, and stimulating incentives, play essential roles for better management. The unknown waste-dumping behaviour of residents is a great challenge for decision-makers to allocate resources for waste-collection operations and to refine regulations. Traditional behaviour analysis methods such as questionnaire surveys and simulation methods have limitations considering the population size and the complexity of individual behaviour. This study aims to design a data-driven analytical framework to analyse household waste-dumping behaviour and facilitate policy regulations by using the Internet of Things (IoT) and data mining technologies. The analytical framework is further developed into a four-step management cycle. A case study in Shanghai is employed to demonstrate the effectiveness of the analytical framework and management cycle. The results of behaviour analyses reveal that (1) waste-dumping frequency is high in the evening but negligible in the early afternoon; (2) compared to working days, peak-value time at weekends occurs later in the morning and earlier in the evening; (3) residents require longer waste-dumping time windows than those empirically recommended by administrators. Managerial insights and decision support based on these research results have been presented for decision-makers to guide operations management and facilitate policy regulations.

2.
Int J Biol Macromol ; 147: 453-462, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31923519

RESUMO

Due to the favorable stability, water solubility and good biocompatibility, carbon dots have attracted much attention. Herein, a novel nitrogen-doping bifunctional carbon dots (N-BCDs) with ultra-highly quantum yield (QYabs = 70.4%) is prepared through microwave-assisted method. 50 µg/mL of N-BCDs emit intense fluorescence in HeLa and GES-1 cells with negligible cytotoxicity. In addition, effective inhibition of N-BCDs to human insulin (HI) fibrillation is observed even at 10:1 (mass ratio of HI: N-BCDs) by ThT fluorescence, CD assay and TEM. N-BCDs prevent HI from fibrillation with prolonged lag time and reduced fluorescent intensity at equilibrium, regardless of the addition time of N-BCDs (HI: N-BCDs = 1:1, mass ratio), which has been rarely reported before. Furthermore, the morphology of final HI fibrils is shorter and thinner in the presence of N-BCDs. Mechanism studies reveal that the enhanced hydrogen bond between HI monomers and N-BCDs inhibits nucleation during the lag stage (Ka: 1.54 × 104 L·mol-1, 298 K), while the accumulation of N-BCDs blocks the growth of profibrils in the elongation stage. To the best of our knowledge, it's the first time to observe the accumulation of N-BCDs around HI profibrils with TEM. Our study provides a new strategy for developing efficient nanoparticle inhibitors for protein fibrillation.

3.
J Colloid Interface Sci ; 565: 77-85, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31935587

RESUMO

Carbon dots (CDs) is a class of zero-dimensional carbon nanomaterials with favorable stability and optical properties. However, CDs in solid state often suffer from fluorescence quenching due to π-π stacking of conjugated systems, like most small molecules or organic dyes. Herein, we prepared the CDs that generate bright yellow luminescence in solid state without any additional matrix, meanwhile the solid CDs are inclined to assembly into spherical structure. While the CDs are dissolved in aqueous solution, the photoluminescence (PL) emission from blue to green can be realized by regulating the concentration of CDs. With the concentration increasing, the self-assembly behavior of CDs is observed in solution, which leads to the bathochromic shift of photoluminescence. Besides, the mechanism of PL conversion in this process was proposed based on the characterization results, that with the concentration of CDs rising in solution, π-π interaction was restrained while electron redistribution was induced. Consequently, a localized state II caused by electron rearrangement gradually becomes the predominant emission state, resulting in the PL emission shifting to long-wavelength region. Moreover, CDs have shown favorable potentials in the field of anti-counterfeit and multicolor bioimaging, making the CDs highly attractive for a wide variety of applications.

4.
Int Immunopharmacol ; 79: 106155, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31918059

RESUMO

BACKGROUND: ALOX5, IL6R and SFTPD are all immune related genes that may be involved in the development of lung cancer. We sought to explore the effect of polymorphisms of these genes on the risk of lung cancer. METHODS: Six single nucleotide polymorphisms (SNPs) were genotyped using a MassARRAY platform in a case-control cohort including 550 patients with lung cancer and 550 healthy controls. RESULTS: The rs4845626-T and rs4329505-C alleles were associated with a decreased risk of lung cancer (p < 0.001), while the rs745986-G and rs2245121-A alleles were correlated with an increased risk of lung cancer (p < 0.01). The rs4845626-GT/GG and rs4329505-TC genotypes were protective against lung cancer (p < 0.001). However, the rs745986-AG and rs2245121-AG/AA genotypes were associated with an increased risk of lung cancer (p < 0.01). Stratification analysis showed that the rs4845626 and rs4329505 polymorphisms of IL6R were associated with a reduced risk of lung cancer in both smokers and nonsmokers (p < 0.05). However, rs892690, rs745986 and rs2115819 of ALOX5 were associated with an increased risk of disease in nonsmokers, while rs2245121 of SFTPD was correlated with a higher risk of disease in smokers (p < 0.05). CONCLUSION: Our results provide candidate SNPs for early screening for lung cancer and new clues for further study of the pathogenesis of the disease.

5.
Proc Natl Acad Sci U S A ; 117(2): 1027-1035, 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31888991

RESUMO

Epithelial cell transforming 2 (Ect2) protein activates Rho GTPases and controls cytokinesis and many other cellular processes. Dysregulation of Ect2 is associated with various cancers. Here, we report the crystal structure of human Ect2 and complementary mechanistic analyses. The data show the C-terminal PH domain of Ect2 folds back and blocks the canonical RhoA-binding site at the catalytic center of the DH domain, providing a mechanism of Ect2 autoinhibition. Ect2 is activated by binding of GTP-bound RhoA to the PH domain, which suggests an allosteric mechanism of Ect2 activation and a positive-feedback loop reinforcing RhoA signaling. This bimodal RhoA binding of Ect2 is unusual and was confirmed with Förster resonance energy transfer (FRET) and hydrogen-deuterium exchange mass spectrometry (HDX-MS) analyses. Several recurrent cancer-associated mutations map to the catalytic and regulatory interfaces, and dysregulate Ect2 in vitro and in vivo. Together, our findings provide mechanistic insights into Ect2 regulation in normal cells and under disease conditions.

6.
Curr Alzheimer Res ; 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31894747

RESUMO

BACKGROUND: The specific intravenous immunoglobulin (IVIG) for Alzheimer's disease (AD) is developing, which contains a high level of naturally occurring autoantibodies against amyloid-ß (nAbs-Aß), and the measure of nAbs-Aß content is greatly essential. Though enzyme-linked immunosorbent assay (ELISA) has been widely used in detecting the nAbs-Aß content, the impact of Aß aggregates species chosen as antigen in ELISA on this measure has not been evaluated. OBJECTIVE: To clarify the influence of different Aß40/42 aggregates as antigen during ELISA on the content of nAbs-Aß40/42 measured in IVIG. METHOD: Preparation of various Aß40/42 aggregates was performed by different aggregation solutions and various lengths of time, and analyzed by western blot. Different Aß40/42 aggregates as antigen were adopted to measure the nAbs-Aß40/42 content in IVIG by ELISA, and the control was carried out to reduce interference of nonspecific binding. The Bonferroni and Dunnett's T3 were used for statistical analysis. RESULTS: The duration for the formation of Aß40/42 aggregates had more effect on detecting nAbs-Aß40/42 content in IVIG than the aggregation solution. Higher content of nAbs-Aß40/42 in the same IVIG was displayed when measured with Aß40/42 aggregates at day 3, instead of at day 0.5 and day 7.0. The nAbs-Aß40/42 contents in the same IVIG measured with Aß40/42 aggregates prepared in different solutions were obviously different, but there was no significant regularity among them. CONCLUSION: The nAbs-Aß40/42 content in the same IVIG is significantly different when measured with Aß40/42 aggregated under different conditions. The nAbs-Aß40/42 content in IVIG by antigen-dependent measures, like ELISA, is uncertain.

7.
Theor Appl Genet ; 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31897512

RESUMO

KEY MESSAGE: Eight environmentally stable QTL for grain yield-related traits were detected by four RIL populations, and two of them were validated by a natural wheat population containing 580 diverse varieties or lines. Yield and yield-related traits are important factors in wheat breeding. In this study, four RIL populations derived from the cross of one common parent Yanzhan 1 (a Chinese domesticated cultivar) and four donor parents including Hussar (a British domesticated cultivar) and three semi-wild wheat varieties in China were phenotyped for 11 yield-related traits in eight environments. An integrated genetic map containing 2009 single-nucleotide polymorphism (SNP) markers generated from a 90 K SNP array was constructed to conduct quantitative trait loci (QTL) analysis. A total of 161 QTL were identified, including ten QTL for grain yield per plant (GYP) and yield components, 49 QTL for spike-related traits, 43 QTL for flag leaf-related traits, 22 QTL for plant height (PH), and 37 QTL for heading date and flowering date. Eight environmentally stable QTL were validated in individual RIL population where the target QTL was notably detected, and six of them had a significant effect on GYP. Furthermore, Two QTL, QSPS-2A.4 and QSL-4A.1, were also validated in a natural wheat population containing 580 diverse varieties or lines, which provided valuable resources for further fine mapping and genetic improvement in yield in wheat.

8.
New Phytol ; 225(1): 234-249, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31419316

RESUMO

Brown algae have convergently evolved plant-like body plans and reproductive cycles, which in plants are controlled by differential DNA methylation. This contribution provides the first single-base methylome profiles of haploid gametophytes and diploid sporophytes of a multicellular alga. Although only c. 1.4% of cytosines in Saccharina japonica were methylated mainly at CHH sites and characterized by 5-methylcytosine (5mC), there were significant differences between life-cycle stages. DNA methyltransferase 2 (DNMT2), known to efficiently catalyze tRNA methylation, is assumed to methylate the genome of S. japonica in the structural context of tRNAs as the genome does not encode any other DNA methyltransferases. Circular and long noncoding RNA genes were the most strongly methylated regulatory elements in S. japonica. Differential expression of genes was negatively correlated with DNA methylation with the highest methylation levels measured in both haploid gametophytes. Hypomethylated and highly expressed genes in diploid sporophytes included genes involved in morphogenesis and halogen metabolism. The data herein provide evidence that cytosine methylation, although occurring at a low level, is significantly contributing to the formation of different life-cycle stages, tissue differentiation and metabolism in brown algae.

9.
Atherosclerosis ; 292: 99-111, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31785495

RESUMO

BACKGROUND AND AIMS: "Shexiang Baoxin Pill" (SBP), a commonly used traditional Chinese medicine, has been used to treat angina, myocardial infarction and coronary heart disease in China for thirty years. SBP has been proven to promote angiogenesis in a rat model of myocardial infarction (MI). The aim of the present study was to determine the pro-angiogenic effects and mechanism of SBP during inflammation or ischemic pathological conditions and elucidate its regulatory effects on endothelial cell function and signaling pathways mediated by macrophages. METHODS: We used a polyvinyl alcohol (PVA) sponge implantation mouse model as an inflammatory angiogenesis model and utilized a mouse femoral artery ligation model as a hind limb ischemia model. We also performed cell proliferation, cell migration and tubule formation in vitro experiments to assess the effects of SBP on endothelial cell function and signaling pathways by stimulating macrophage activity. RESULTS: The in vitro experiment results showed that SBP could significantly increase the expression of mRNAs and proteins associated with angiogenesis in endothelial cells by activating macrophages to release pro-angiogenic factors such as Vegf-a. Activation of macrophages by SBP eventually led to endothelial cell proliferation, migration and tubule formation and increased the expression of p-Akt and p-Erk1/2 proteins in the downstream PI3K/Akt and MAPK/Erk1/2 signaling pathways related to angiogenesis, respectively. The in vivo experiment results indicated that SBP had angiogenesis effects in both inflammatory and ischemic angiogenesis models with dose- and time-dependent effects. CONCLUSION: Shexiang Baoxin Pills can promote angiogenesis by activating macrophages to regulate endothelial cell function and signal transduction pathways.

10.
J Autoimmun ; : 102372, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31810856

RESUMO

The genetic association of primary biliary cholangitis with major histocompatibility complex (MHC) has been widely confirmed among different ethnicities. To map specific MHC region variants associated with PBC in a Han Chinese cohort, we imputed HLA antigens and amino acids (AA) in 1126 PBC cases and 1770 healthy control subjects using a Han-MHC reference database. We demonstrate that HLA-DRB1 and/or HLA-DQB1 contributed the strongest signals, and that HLA-DPB1 was a separate independent locus. Regression analyses with classical HLA alleles indicate that HLA-DQB1*03:01 or HLA-DQß1-Pro55, HLA-DPB1*17:01 or HLA-DPß1-Asp84 and HLA-DRB1*08:03 could largely explain MHC association with PBC. Forward stepwise regression analyses with HLA amino acid variants localize the major signals to HLA-DRß1-Ala74, HLA-DQß1-Pro55 and HLA-DPß1-Asp84. Electrostatic potential calculations implicated AA variations at HLA-DQß1 position 55 and HLA-DPß1 position 84 as critical to peptide binding properties. Furthermore, although several critical Han Chinese AA variants differed from those shown in European populations, the predicted effects on antigen binding are likely to be very similar or identical and underlie the major component of MHC association with PBC.

11.
Virol J ; 16(1): 153, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31818304

RESUMO

BACKGROUND: Publicly available transcriptomic datasets have become a valuable tool for the discovery of new pathogens, particularly viruses. In this study, several coding-complete viral genomes previously not found or experimentally confirmed in alfalfa were identified in the plant datasets retrieved from the NCBI Sequence Read Archive. METHODS: Publicly available Medicago spp. transcriptomic datasets were retrieved from the NCBI SRA database. The raw reads were first mapped to the reference genomes of Medicago sativa and Medigago truncatula followed by the alignment of the unmapped reads to the NCBI viral genome database and de novo assembly using the SPAdes tool. When possible, assemblies were experimentally confirmed using 5'/3' RACE and RT-PCRs. RESULTS: Twenty three different viruses were identified in the analyzed datasets, of which several represented emerging viruses not reported in alfalfa prior to this study. Among them were two strains of cnidium vein yellowing virus, lychnis mottle virus and Cactus virus X, for which coding-complete genomic sequences were obtained by a de novo assembly. CONCLUSIONS: The results improve our knowledge of the diversity and host range of viruses infecting alfalfa, provide essential tools for their diagnostics and characterization and demonstrate the utility of transcriptomic datasets for the discovery of new pathogens.

12.
Artigo em Inglês | MEDLINE | ID: mdl-31789139

RESUMO

BACKGROUND: Hashimoto's thyroiditis (HT) is characterized by lymphocytic infiltration of the thyroid parenchyma, which ultimately leads to tissue destruction and loss of function. Caveolin-1 (Cav-1) is an essential structural constituent of lipid rafts in the plasma membrane of cells and is reported to be significantly reduced in thyrocytes from HT patients. However, the mechanism of Cav-1 involvement in HT pathogenesis is still largely unclear. METHODS: Cav-1 expression in thyroid tissues from HT patients and euthyroid nodular goiter tissues was detected by immunohistochemistry staining. Cav-1 knockdown and overexpression were constructed by lentiviral transfection in the human thyroid follicular epithelial cell (TFC) line of Nthy-ori 3-1. The mRNA expression levels of chemokines in TFCs were determined by quantitative real-time PCR (qPCR). Cav-1 and peroxisome proliferator-activated receptor gamma (PPARγ) levels were analysed by qPCR and Western blot analysis. The migration ability of peripheral blood mononuclear cells (PBMCs) was detected by the Transwell assay. RESULTS: In this study, Cav-1 and PPARγ expression was reduced in the thyroid tissues from HT patients. In vitro experiments showed that the expressions of chemokine (C-C motif) ligand 5 (CCL5) and migration of PBMCs were markedly increased, while the level of PPARγ was significantly decreased after the lentivirus-mediated knockdown of Cav-1 in Nthy-ori 3-1 cells. Interestingly, pioglitazone, a PPARγ agonist, not only upregulated PPARγ and Cav-1 proteins significantly, but also effectively reversed the Cav-1-knockdown-induced upregulation of CCL5 in Nthy-ori 3-1 cells and reduced the infiltration of lymphocytes. CONCLUSION: The inhibition of Cav-1 upregulated the CCL5 expression and downregulated the PPARγ expression in TFC while pioglitazone, a PPARγ agonist, reversed the detrimental consequence. This outcome might be a potential target for the treatment of lymphocyte infiltration into the thyroid gland and HT development.

13.
Vet Res ; 50(1): 106, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31806006

RESUMO

The binding and activation of host plasminogen (PLG) by worm surface enolases has been verified to participate in parasite invasion, but the role of this processes during Trichinella spiralis infection has not been clarified. Therefore, the expression and immunolocalization of a T. spiralis enolase (TsENO) and its binding activity with PLG were evaluated in this study. Based on the three-dimensional (3D) molecular model of TsENO, the protein interaction between TsENO and human PLG was analysed by the ZDOCK server. The interacting residues were identified after analysis of the protein-protein interface by bioinformatics techniques. The key interacting residues were confirmed by a series of experiments. The qPCR analysis results demonstrated that Ts-eno was transcribed throughout the whole life cycle of T. spiralis. The immunofluorescence assay (IFA) results confirmed that TsENO was distributed on the T. spiralis surface. The binding assays showed that recombinant TsENO (rTsENO) and native TsENO were able to bind PLG. Four lysine residues (90, 289, 291 and 300) of TsENO were considered to be active residues for PLG interaction. The quadruple mutant (Lys90Ala + Lys289Ala + Lys291Ala + Lys300Ala) TsENO, in which the key lysine residues were substituted with alanine (Ala) residues, exhibited a reduction in PLG binding of nearly 50% (45.37%). These results revealed that TsENO has strong binding activity with human PLG. The four lysine residues (90, 289, 291 and 300) of TsENO play an important role in PLG binding and could accelerate PLG activation and invasion of the host's intestinal wall by T. spiralis.

14.
Parasit Vectors ; 12(1): 581, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31829230

RESUMO

BACKGROUND: Trichinella spiralis is a major zoonotic tissue-dwelling nematode, which is a public health concern and a serious hazard to animal food safety. It is necessary to exploit an anti-Trichinella vaccine to interrupt the transmission of Trichinella infection among animals and from animals to humans. The purpose of the present study was to characterize the novel T. spiralis cathepsin B (TsCB) and to evaluate the immune protection elicited by immunization with recombinant TsCB (rTsCB). METHODS: The complete cDNA sequences of the TsCB gene were cloned, expressed and purified. The antigenicity of rTsCB was investigated by western blot analysis and ELISA. Transcription and expression of TsCB at various T. spiralis life-cycle stages were analyzed by RT-PCR and indirect immunofluorescent assay (IIFA). The mice were subcutaneously immunized with rTsCB, and serum level of TsCB-specific IgG (IgG1 and IgG2a) and IgE antibodies were assayed by ELISA. Immune protection elicited by vaccination with rTsCB was investigated. RESULTS: The TsCB was transcribed and expressed in four T. spiralis life-cycle stages (adult worm, AW; newborn larvae, NBL; muscle larvae, ML; and intestinal infective L1 larvae), it was primarily located in the cuticle and stichosome of the parasitic nematode. Vaccination of mice with rTsCB produced a prominent antibody response (high level of specific IgG and IgE) and immune protection, as demonstrated by a 52.81% AW burden reduction of intestines at six days post-infection (dpi) and a 50.90% ML burden reduction of muscles at 35 dpi after oral larva challenge. The TsCB-specific antibody response elicited by immunization with rTsCB also impeded intestinal worm growth and decreased the female fecundity. CONCLUSIONS: TsCB might be considered as a novel potential molecular target to develop vaccines against T. spiralis infection.

15.
Artigo em Inglês | MEDLINE | ID: mdl-31853878

RESUMO

Recombinant phycobiliprotein can be used as fluorescent label in immunofluorescence assay. In this study, pathway for phycocyanin beta subunit (CpcB) carrying noncognate chromophore phycoerythrobilin (PEB) and phycourobilin (PUB) was constructed in Escherichia coli. Lyase CpcS and CpcT could catalyze attachment of PEB to Cys84-CpcB and Cys155-CpcB, respectively. However, PEB was attached only to Cys84-CpcB when both CpcS and CpcT were present in E. coli. A dual plasmid expression system was used to control the expression of lyases and the attachment order of PEB to CpcB. The production of PEB-Cys155-CpcB was achieved by L-arabinose-induced expression of CpcS, CpcB, Ho1, and PebS, and then the attachment of PEB to Cys84-CpcB was achieved by IPTG-induced expression of CpcS. The doubly chromophorylated CpcB absorbed light maximally at 497.5 nm and 557.0 nm and fluoresced maximally at 507.5 nm and 566.5 nm. An amount of light energy absorbed by PUB-Cys155-CpcB is transferred to PEB-Cys84-CpcB in doubly chromophorylated CpcB, conferring a large stokes shift of 69 nm for this fluorescent protein. There are interactions between chromophores of CpcB which possibly together with the help of lyases lead to isomerization of PEB-Cys155-CpcB to PUB-Cys155-CpcB.

16.
J Prosthet Dent ; 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31864638

RESUMO

STATEMENT OF PROBLEM: Digital scans have increasingly become an alternative to conventional impressions. Although previous studies have analyzed the accuracy of the available intraoral scanners (IOSs), the effect of the light scanning conditions on the accuracy of those IOS systems remains unclear. PURPOSE: The purpose of this in vitro study was to measure the impact of lighting conditions on the accuracy (trueness and precision) of different IOSs. MATERIAL AND METHODS: A typodont was digitized by using an extraoral scanner (L2i; Imetric) to obtain a reference standard tessellation language (STL) file. Three IOSs were evaluated-iTero Element, CEREC Omnicam, and TRIOS 3-with 4 lighting conditions-chair light 10 000 lux, room light 1003 lux, natural light 500 lux, and no light 0 lux. Ten digital scans per group were recorded. The STL file was used as a reference to measure the discrepancy between the digitized typodont and digital scans by using the MeshLab software. The Kruskal-Wallis, 1-way ANOVA, and pairwise comparison were used to analyze the data. RESULTS: Significant differences for trueness and precision mean values were observed across different IOSs tested with the same lighting conditions and across different lighting conditions for a given IOS. In all groups, precision mean values were higher than their trueness values, indicating low relative precision. CONCLUSIONS: Ambient lighting conditions influenced the accuracy (trueness and precision) of the IOSs tested. The recommended lighting conditions depend on the IOS selected. For iTero Element, chair and room light conditions resulted in better accuracy mean values. For CEREC Omnicam, zero light resulted in better accuracy, and for TRIOS 3, room light resulted in better accuracy.

17.
J Prosthet Dent ; 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31870612

RESUMO

STATEMENT OF PROBLEM: Digital scans should be able to accurately reproduce the different complex geometries of the patient's mouth. Mesh quality of the digitized mouth is an important factor that influences the capabilities of the geometry reproduction of an intraoral scanner (IOS). However, the mesh quality capabilities of IOSs and the relationship with different ambient light scanning conditions are unclear. PURPOSE: The purpose of this in vitro study was to measure the impact of various light conditions on the mesh quality of different IOSs. MATERIAL AND METHODS: Three IOSs were evaluated-iTero Element, CEREC Omnicam, and TRIOS 3-with 4 lighting conditions-chair light, 10 000 lux; room light, 1003 lux; natural light, 500 lux; and no light, 0 lux. Ten digital scans per group were made of a mandibular typodont. The mesh quality of digital scans was analyzed by using the iso2mesh MATLAB package. Two-way ANOVA and Kruskal-Wallis 1-way ANOVA statistical tests were used to analyze the data (á=.05). RESULTS: Significant differences in mesh quality values were found among the different IOSs under the same lighting conditions and among the different lighting conditions using the same IOS. TRIOS 3 showed the highest consistency and mesh quality mean values across all scanning lighting conditions tested. CEREC Omnicam had the lowest mean mesh quality values across all scanning lighting conditions. iTero Element displayed some consistency in the mesh quality values depending on the scanning lighting conditions: chair light and room light conditions presented good consistency in mesh quality, indicating better mesh quality, and natural light and no light conditions displayed differing consistency in mesh quality values. Nevertheless, no light condition led to the minimal mean mesh quality across all IOS groups. CONCLUSIONS: Differences in the mesh quality between different IOSs should be expected. The photographic scanning techniques evaluated presented higher mesh quality mean values than the video-based scanning technology tested. Moreover, changes in lighting condition significantly affect mesh quality. TRIOS 3 showed the highest consistency in terms of the mean mesh quality, indicating better photographic system in comparison with iTero Element.

18.
Micromachines (Basel) ; 10(11)2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31671834

RESUMO

With the last decades of development, earthquake early warning (EEW) has proven to be one of the potential means for disaster mitigation. Usually, the density of the EEW network determines the performance of the EEW system. For reducing the cost of sensors and building a dense EEW network, an upgraded low-cost Micro Electro Mechanical System (MEMS)-based sensor named GL-P2B was developed in this research. This device uses a new high-performance CPU board and is built on a custom-tailored Linux 3.6.9 operating system integrating with seismological processing. Approximately 170 GL-P2Bs were installed and tested in the Sichuan-Yunnan border region from January 2017 to December 2018. We evaluated its performance on noise-level, dynamic range (DR), useful resolution (NU), collocated recording comparison, and shake map generation. The results proved that GL-P2B can be classified as a type of Class-B sensor. The records obtained are consistent with the data obtained by the collocated traditional force-balanced accelerometers even for stations with an epicenter distance of more than 150 km, and most of the relative percentage difference of peak ground acceleration (PGA) values is smaller than 10%. In addition, with the current density of the GL-P2B seismic network, near-real-time refined shake maps without using values derived for virtual stations could be directly generated, which will significantly improve the capability for earthquake emergency response. Overall, this MEMS-based sensor can meet the requirements of dense EEW purpose and lower the total investment of the National System for Fast Seismic Intensity Report and Earthquake Early Warning project.

19.
Mar Drugs ; 17(12)2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31779128

RESUMO

Normal intestinal flora is widely involved in many functions of the host: nutritional metabolism; maintenance of intestinal microecological balance; regulation of intestinal endocrine function and nerve signal transduction; promotion of intestinal immune system development and maturation; inhibition of pathogenic bacteria growth and colonization, reduction of its invasion to intestinal mucosa, and so on. In recent years, more and more studies have shown that intestinal flora is closely related to the occurrence, development, and treatment of various tumors. It is indicated that recombinant phycoerythrin (RPE) has significant anti-tumor and immunomodulatory effects. However, little is known about the mechanism of the effect of oral (or intragastric) administration of RPE on gut microbiota in tumor-bearing animals. In this study, using high-throughput 16S rDNA sequencing, we examined the response of gut microbiota in H22-bearing mice to dietary RPE supplementation. The results showed that the abundance of beneficial bacteria in the mice intestinal flora decreased and that of the detrimental flora increased after inoculation with tumor cells (H22); following treatment with dietary RPE, the abundance of beneficial bacteria in the intestinal flora significantly increased and that of detrimental bacteria decreased. In this study, for the first time, it was demonstrated that dietary RPE could modulate the gut microbiota of the H22 bearing mice by increasing the abundance of beneficial bacteria and decreasing that of detrimental bacteria among intestinal bacteria, providing evidence for the mechanism by which bioactive proteins affect intestinal nutrition and disease resistance in animals.

20.
Front Genet ; 10: 1093, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31737057

RESUMO

In China, the nematode Trichinella spiralis is the main aetiological agent of human trichinellosis. We performed multi-locus microsatellite typing of T. spiralis isolates to improve the current knowledge of the evolution and population diversity. First, seven polymorphic microsatellite loci were used to infer the genetic diversity of T. spiralis collected in 10 endemic regions. Then, a Bayesian model-based STRUCTURE analysis, a clustering based on the neighbor-joining method, and a principal coordinate analysis (PCA) were performed to identify the genetic structure. Finally, the phylogenetic position of Chinese isolates was explored based on six mitochondrial and nuclear genetic markers (cox1, cytb, 5S ISR, ESV, ITS1, and 18S rDNA) using the maximum likelihood and Bayesian methods. In addition, the divergence time was estimated with multiple genes using an uncorrelated log-normal relaxed molecular-clock model. A total of 16 alleles were detected in 2,310 individuals (1,650 muscle larvae and 660 adult worms) using seven loci. The STRUCTURE analysis indicated that the T. spiralis isolates could be organized and derived from the admixture of two ancestral clusters, which was also substantiated through the clustering analysis based on the allelic data. PCA separated most samples from Tiandong, Guangxi (GX-td), and Linzhi, Tibet (Tibet-lz), from the remaining isolates. However, both maximum likelihood and Bayesian inference supported the close relationship between Xiangfan, Hubei (HB-xf), and GX-td. The molecular dating analysis suggested that the Chinese isolates started to diverge during the Late Pleistocene (0.69 Mya). Generally, T. spiralis was observed to harbor low genetic variation, and further investigation with deeper sampling is needed to elucidate the population structure.

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