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1.
Mult Scler Relat Disord ; 81: 105146, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38007962

RESUMO

OBJECTIVE: To investigate the abnormal radiomics features of the hippocampus in patients with multiple sclerosis (MS) and neuromyelitis optica spectrum disorders (NMOSD) and to explore the clinical implications of these features. METHODS: 752 participants were recruited in this retrospective multicenter study (7 centers), which included 236 MS, 236 NMOSD, and 280 normal controls (NC). Radiomics features of each side of the hippocampus were extracted, including intensity, shape, texture, and wavelet features (N = 431). To identify the variations in these features, two-sample t-tests were performed between the NMOSD vs. NC, MS vs. NC, and NMOSD vs. MS groups at each site. The statistical results from each site were then integrated through meta-analysis. To investigate the clinical significance of the hippocampal radiomics features, we conducted further analysis to examine the correlations between these features and clinical measures such as Expanded Disability Status Scale (EDSS), Brief Visuospatial Memory Test (BVMT), California Verbal Learning Test (CVLT), and Paced Auditory Serial Addition Task (PASAT). RESULTS: Compared with NC, patients with MS exhibited significant differences in 78 radiomics features (P < 0.05/862), with the majority of these being texture features. Patients with NMOSD showed significant differences in 137 radiomics features (P < 0.05/862), most of which were intensity features. The difference between MS and NMOSD patients was observed in 47 radiomics features (P < 0.05/862), mainly texture features. In patients with MS and NMOSD, the most significant features related to the EDSS were intensity and textural features, and the most significant features related to the PASAT were intensity features. Meanwhile, both disease groups observed a weak correlation between radiomics data and BVMT. CONCLUSION: Variations in the microstructure of the hippocampus can be detected through radiomics, offering a new approach to investigating the abnormal pattern of the hippocampus in MS and NMOSD.


Assuntos
Esclerose Múltipla , Neuromielite Óptica , Humanos , Neuromielite Óptica/diagnóstico por imagem , Esclerose Múltipla/diagnóstico por imagem , Radiômica , Estudos Retrospectivos , Estudos Multicêntricos como Assunto
2.
Lipids Health Dis ; 16(1): 145, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28764799

RESUMO

BACKGROUND: Schisandra, a globally distributed plant, has been widely applied for the treatment of diseases such as hyperlipidemia, fatty liver and obesity in China. In the present work, a rapid resolution liquid chromatography coupled with quadruple-time-of-flight mass spectrometry (RRLC-Q-TOF-MS)-based metabolomics was conducted to investigate the intervention effect of Schisandra chinensis lignans (SCL) on hyperlipidemia mice induced by high-fat diet (HFD). METHODS: Hyperlipidemia mice were orally administered with SCL (100 mg/kg) once a day for 4 weeks. Serum biochemistry assay of triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-c) and high-density lipoprotein cholesterol (HDL-c) was conducted to confirm the treatment of SCL on lipid regulation. Metabolomics analysis on serum samples was carried out, and principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) were carried out for the pattern recognition and characteristic metabolites identification. The relative levels of critical regulatory factors of liver lipid metabolism, sterol regulatory element-binding proteins (SREBPs) and its related gene expressions were measured by quantitative real-time polymerase chain reaction (RT-PCR) for investigating the underlying mechanism. RESULTS: Oral administration of SCL significantly decreased the serum levels of TC, TG and LDL-c and increased the serum level of HDL-c in the hyperlipidemia mice, and no effect of SCL on blood lipid levels was observed in control mice. Serum samples were scattered in the PCA scores plots in response to the control, HFD and SCL group. Totally, thirteen biomarkers were identified and nine of them were recovered to the normal levels after SCL treatment. Based on the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways analysis, the anti-hyperlipidemia mechanisms of SCL may be involved in the following metabolic pathways: tricarboxylic acid (TCA) cycle, synthesis of ketone body and cholesterol, choline metabolism and fatty acid metabolism. Meanwhile, SCL significantly inhibited the mRNA expression level of hepatic lipogenesis genes such as SREBP-1c, fatty acid synthase (FAS) and acetyl-CoA carboxylase (ACC), and decreased the mRNA expression of liver X receptor α (LXRα). Moreover, SCL also significantly decreased the expression level of SREBP-2 and 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR) in the liver of hyperlipidemia mice. CONCLUSION: Anti-hyperlipidemia effect of SCL was confirmed by both serum biochemistry and metabolomics analysis. The mechanism may be related to the down-regulation of LXRα/SREBP-1c/FAS/ACC and SREBP2/HMGCR signaling pathways.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Hiperlipidemias/tratamento farmacológico , Lignanas/uso terapêutico , Metabolômica , Schisandra/química , Animais , Biomarcadores/sangue , Colesterol/sangue , Hiperlipidemias/sangue , Hiperlipidemias/genética , Masculino , Espectrometria de Massas , Redes e Vias Metabólicas/genética , Metaboloma , Camundongos Endogâmicos C57BL , Análise de Componente Principal , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a Elemento Regulador de Esterol/genética , Proteínas de Ligação a Elemento Regulador de Esterol/metabolismo , Triglicerídeos/sangue
3.
J Inequal Appl ; 2017(1): 68, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28435205

RESUMO

The result on the Gersgorin disc separation from the origin for strictly diagonally dominant matrices and their Schur complements in (Liu and Zhang in SIAM J. Matrix Anal. Appl. 27(3):665-674, 2005) is extended to nonstrictly diagonally dominant matrices and their Schur complements, showing that under some conditions the separation of the Schur complement of a nonstrictly diagonally dominant matrix is greater than that of the original grand matrix. As an application, the eigenvalue distribution of the Schur complement is discussed for nonstrictly diagonally dominant matrices to derive some significant conclusions. Finally, some examples are provided to show the effectiveness of theoretical results.

4.
Inorg Chem ; 54(10): 4761-7, 2015 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-25924548

RESUMO

The most advanced UV-vis and IR NLO materials are usually borates and chalcogenides, respectively. But thioborates, especially thio-borometalates, are extremely rare. Here, four new such compounds are discovered by solid state reactions representing 0D structures constructed by isolated BQ3 trigonal planes and discrete MQ3 pyramids with Ba(2+) cations filling among them, centrosymmetric monoclinic P21/c Ba3(BS3)1.5(MS3)0.5 (M = Sb, Bi) 1, 2 with a = 12.9255(9), 12.946(2) Å; b = 21.139(2), 21.170(2)Å; c = 8.4194(6), 8.4207(8) Å; ß = 101.739(5), 101.688(7)°; V = 2252.3(3), 2259.9(3) Å(3) and noncentrosymmetric hexagonal P6̅2m Ba3(BQ3)(SbQ3) (Q = S, Se) 3, 4 with a = b = 17.0560(9), 17.720(4) Å; c = 10.9040(9), 11.251(3) Å; V = 2747.1(3), 3060(2) Å(3). 3 exhibits the strongest SHG among thioborates that is about three times that of the benchmark AgGaS2 at 2.05 µm. 1 and 3 also show an interesting structure relationship correlated to the size mismatching of the anionic building units that can be controlled by the experimental loading ratio of B:Sb. Syntheses, structure characterizations, and electronic structures based on the density functional theory calculations are reported.

5.
Food Microbiol ; 46: 383-394, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25475308

RESUMO

Control of foodborne pathogens in fresh produce is crucial for food safety, and numerous Salmonella Typhimurium (ST) outbreaks have been reported already. The present study was done to assess effectiveness of cold oxygen plasma (COP) against biofilms of ST mixed with cultivable indigenous microorganisms (CIM). ST and CIM were grown at 15 °C as monocultures and mixed cultures for planktonic state, biofilm on stainless steel, and lettuce leaves. Thereafter, the samples were treated with COP and surviving populations were counted using plate counting methods. Biofilms and stomatal colonization were examined using field emission scanning electron microscopy (FESEM) and food quality was assessed after treatment. Mixed cultures of ST and CIM showed an antagonistic interaction on lettuce but not on SS or in planktonic state. Mixed cultures showed significantly (p < 0.05) greater resistance to COP compared to monoculture biofilms on lettuce but not on SS or planktonic state. Shift from smooth to rugose colony type was found for planktonic and for biofilms on SS but not on lettuce for ST. Mixed culture biofilms colonized stomata on the inside as demonstrated by FESEM. Although, lettuce quality was not affected by COP, this technology has to be optimized for further development of the successful inactivation of complex multispecies biofilm structures presented by real food environment.


Assuntos
Biofilmes/efeitos dos fármacos , Lactuca/microbiologia , Oxigênio/farmacologia , Gases em Plasma/farmacologia , Salmonella typhimurium/efeitos dos fármacos , Temperatura Baixa , Oxigênio/química , Folhas de Planta/microbiologia , Salmonella typhimurium/crescimento & desenvolvimento , Salmonella typhimurium/fisiologia
6.
Foodborne Pathog Dis ; 11(8): 658-63, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24971770

RESUMO

The present study investigated the efficacy of single and combined treatment of both chlorine and thiamine dilaurylsulfate (TDS) on the reduction of Listeria monocytogenes biofilms in microtiter plate. The disinfectants used in this study were 50, 100, and 200 mg/L chlorine and 100, 500, and 1000 mg/L of TDS. Biofilm-forming index (BFI) and culturable cell count were used to evaluate the disinfectant assay. The highest BFI reduction was 0.80, achieved by the combination of 200 mg/L chlorine and 1000 mg/L TDS. In contrast, the highest culturable cell count reduction was 4.80 log colony-forming units/well by the combination of 200 mg/L chlorine and 100 mg/L TDS. The BFI was reduced in a concentration-dependent manner while culturable cell count was significantly reduced only when all chlorine concentration was combined with 100 mg/L TDS. However, when chlorine was combined with a higher concentration of TDS, the reduction decreased significantly. The result in this study showed that the combination of the 200 mg/L chlorine and 1000 mg/L TDS could be a practical application in removing L. monocytogenes biofilms from surfaces in food industry, and for the 200 mg/L chlorine and 100 mg/L, it can be used for killing the pathogen biofilms. However, more studies are still needed in order to show its efficacy on foods surfaces as well as to develop an even more effective treatment in both killing and removing biofilms.


Assuntos
Biofilmes/efeitos dos fármacos , Cloro/farmacologia , Desinfetantes/farmacologia , Listeria monocytogenes/efeitos dos fármacos , Tiamina/farmacologia , Contagem de Colônia Microbiana , Relação Dose-Resposta a Droga , Contaminação de Alimentos/prevenção & controle , Manipulação de Alimentos , Microbiologia de Alimentos , Listeria monocytogenes/isolamento & purificação , Microscopia Eletrônica de Varredura , Tiamina/química
7.
Ying Yong Sheng Tai Xue Bao ; 24(4): 1047-54, 2013 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-23898664

RESUMO

To accurately interpolate the missing precipitation data from meteorological observation stations within a region to obtain a complete precipitation series is of significance in improving the spatial and temporal resolution in analyzing the effects of climate change. By using spatial correlation and stepwise regression techniques, this paper interpolated the missing precipitation data for an individual day or less than 7 days in a month from the 853 meteorological stations in the forest region of Eastern China in 1961-2010, as a consequent establishment of the complete time series precipitation datasets of the observation stations in 1961-2010 established. Based on these, trend analysis approach was applied to analyze the variation characteristics of the annual precipitation, annual precipitation days, and extreme precipitation events in the region in 1961-2010. During the study period, the annual precipitation in the region presented an insignificant increasing trend, with a tendency of 5.58 mm (10 a) -1, but the decadal variation was obvious. The annual precipitation days reduced significantly, while the annual extreme precipitation days and extreme precipitation volumes increased significantly, with a tendency of 0.12 d (10 a) -1 and 10. 22 mm (10 a)-1, respectively. Since the 1990s, the extreme precipitation events became frequently and intensively, and the proportion of the volumes of extreme precipitation to total precipitation increased significantly. Both the extreme precipitation days and the volumes of extreme precipitation had an abrupt change in 1993.


Assuntos
Ecossistema , Monitoramento Ambiental/estatística & dados numéricos , Chuva , Árvores/crescimento & desenvolvimento , China , Coleta de Dados , Análise de Regressão , Análise Espaço-Temporal
8.
ACS Appl Mater Interfaces ; 5(12): 5757-62, 2013 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-23742204

RESUMO

The controlled growth and alignment of one-dimensional organic nanostructures at well-defined locations considerably hinders the integration of nanostructures for electronic and optoelectronic applications. Here, we demonstrate a simple process to achieve the growth, alignment, and hierarchical patterning of organic nanowires on substrates with controlled patterns of surface wettability. The first-level pattern is confined by the substrate patterns of wettability. Organic nanostructures are preferentially grown on solvent wettable regions. The second-level pattern is the patterning of aligned organic nanowires deposited by controlling the shape and movement of the solution contact lines during evaporation on the wettable regions. This process is controlled by the cover-hat-controlled method or vertical evaportation method. Therefore, various new patterns of organic nanostructures can be obtained by combing these two levels of patterns. This simple method proves to be a general approach that can be applied to other organic nanostructure systems. Using the as-prepared patterned nanowire arrays, an optoelectronic device (photodetector) is easily fabricated. Hence, the proposed simple, large-scale, low-cost method of preparing patterns of highly ordered organic nanostructures has high potential applications in various electronic and optoelectronic devices.


Assuntos
Nanotecnologia/métodos , Nanofios/química , Aminofenóis/química , Ciclobutanos/química , Teste de Materiais , Cloreto de Metileno/química , Semicondutores , Dióxido de Silício/química , Solventes/química , Volatilização , Molhabilidade
9.
Appl Opt ; 52(12): 2653-8, 2013 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-23669673

RESUMO

In this paper, the equivalent particle number density distribution of gas and plasma flow fields is investigated. For the purpose of facilitating comparison, argon gas and argon arc plasma are chosen as practical examples for experiment. The equivalent particle number density distributions of the argon gas and argon arc plasma are reconstructed from the experimentally measured refractive index distributions obtained by moiré tomography, while five cross sections, which are 7, 8.5, 10, 11.5, and 13 mm away from the jet nozzle are chosen for practical calculation and comparison. In experiment, the probe wavelength and the export pressure of argon gas and argon arc plasma are the same. The experimental results manifest that (1) the equivalent particle number density decreases with the distance away from the jet nozzle of the gas flow field, while (2) the equivalent particle number density of the plasma flow field has a different variation. Finally, the experimental results are theoretically explained and analyzed.

10.
Appl Opt ; 51(16): 3397-402, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22695575

RESUMO

The effect of arc plasma ionization on its temperature diagnosis by the measurement of the refractive index is discussed. The refractive index of arc plasma in two conditions is compared: 1) only the first ionization is considered and 2) both the first and second ionizations are considered. In order to facilitate plasma temperature reconstruction, two corresponding refractive index models are deduced. For the sake of making this study universal, both the monatomic and dual-atomic molecule arc plasmas are chosen as typical examples for theoretical deduction and analysis. A condition, which can be adopted to estimate whether the second ionization should be considered in temperature reconstruction, is proposed. Finally, an argon arc plasma is chosen as an example for experiment, and the experimental results match well with the theoretical analysis. This study is crucial to arc plasma's optical diagnosis, which is based on the measurement of the refractive index.

11.
Inorg Chem ; 51(13): 7007-9, 2012 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-22702657

RESUMO

New quaternary tellurides, Cs(2)Ge(3)M(6)Te(14) (M = Ga, In), were discovered by solid-state reactions. These compounds crystallize in space group P3ml (No. 164), with a = b = 8.2475(2) Å, c = 14.2734(8) Å, and V = 840.82(6) Å(3) (Z = 1) for Cs(2)Ge(3)Ga(6)Te(14) (1) and a = b = 8.5404(2) Å, c = 14.6766(8) Å, and V = 927.07(6) Å(3) (Z = 1) for Cs(2)Ge(3)In(6)Te(14) (2). The remarkable structural feature is the novel three-dimensional [Ge(3)M(6)Te(14)](2-) anionic framework made by condensed In(6)Te(14) (or Ga(6)Te(14)) layers that are connected alternately by dimeric Ge(3+)(2)Te(6) units and Ge(2+)Te(6) octahedra along the c direction. The presence of Ge centers with different oxidation states is also supported by the results of the electron localization function calculation and X-ray photoelectron spectroscopy measurement.

12.
Ying Yong Sheng Tai Xue Bao ; 21(7): 1867-74, 2010 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-20879549

RESUMO

Forest soil organic carbon is an important component of global carbon cycle, and the changes of its accumulation and decomposition directly affect terrestrial ecosystem carbon storage and global carbon balance. Climate change would affect the photosynthesis of forest vegetation and the decomposition and transformation of forest soil organic carbon, and further, affect the storage and dynamics of organic carbon in forest soils. Temperature, precipitation, atmospheric CO2 concentration, and other climatic factors all have important influences on the forest soil organic carbon storage. Understanding the effects of climate change on this storage is helpful to the scientific management of forest carbon sink, and to the feasible options for climate change mitigation. This paper summarized the research progress about the distribution of organic carbon storage in forest soils, and the effects of elevated temperature, precipitation change, and elevated atmospheric CO2 concentration on this storage, with the further research subjects discussed.


Assuntos
Carbono/análise , Mudança Climática , Compostos Orgânicos/análise , Solo/análise , Árvores/crescimento & desenvolvimento , Poluentes Atmosféricos/análise , Dióxido de Carbono/análise , Ecossistema , Monitoramento Ambiental , Fotossíntese/fisiologia
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(12): 3311-5, 2010 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-21322229

RESUMO

Using the device for ion velocity imaging, the laser frequency is doubling with the wavelength in the region of 492-523 nm, and the laser after frequency doubling was used as the light source. The ion spectrum of methyl iodide parent molecular (CH3 I+) in the range of 76 500-81 120 cm(-1) was obtained by the way of two-photon ionization, with a very high-resolution. The mechanisms of the methyl iodide molecule two-photon ionization were also described, the CH3 I+ spectrum obtained in the experiment was marked based on Rydberg formula and the quantum defect, the split arising from p series, d series and f series levels was also explained, and the spectral assignment showed that the two-photon ionization of methyl iodide molecule can not only be used to observe the reported characteristics of single photon ionization, but also can find some transitions which is forbidden in the single photon ionization, such as f series transitions.

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