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1.
J Colloid Interface Sci ; 660: 166-176, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38241865

RESUMO

NiMo-based electrocatalysts are widely regarded as promising electrocatalysts for overall water splitting (OWS). However, to solve the problem of slow reaction kinetics and serious deactivation at high current density, the reasonable design of NiMo-based electrocatalysts is still a great challenge. In this work, NiMo-based phosphorus/sulfide heterostructure electrocatalysts with different Ce doping ratios (5%/10%/15%Ce-NiMo-PS@NF) have been designed using the combination of cation doping and heterostructure engineering. The doping of Ce not only changes the electronic environment of the heterostructure, accelerates the electron transport at the heterostructure interface, but also enhances the light absorption capacity of the heterostructure. The experimental results show that 10%Ce-NiMo-PS@NF has the best photo-enhanced electrocatalytic activity (hydrogen evolution reaction (HER): η1000 = 250 mV, oxygen evolution reaction (OER): η1000 = 242 mV, and OWS: E1000 = 1.864 V). In addition, its solar-to-hydrogen (STH) efficiency in a photoelectric coupled water splitting system is as high as 18.68%. This study not only provides a new method for the synthesis of new heterostructure electrocatalysts, but also provides a reference for the rational use of light energy to enhance electrocatalytic activity.

2.
Br J Nutr ; 131(2): 321-332, 2024 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-37642161

RESUMO

Despite observed ethnic differences in eating patterns and obesity, evidence in China is limited. This study examined ethnic differences in eating patterns and their associations with weight outcomes among multi-ethnic adults in West China. A cross-sectional survey collected self-reported data on demographics, eating behaviours, weight and height in 2021. Principal component analysis and multivariate regression were conducted to identify eating patterns and examine their associations with weight outcomes. In total, 4407 subjects aged ≥ 18 years were recruited across seven provinces in West China. Four eating patterns were identified: 'meat-lover' - characterised by frequent consumption of meat and dairy products, 'indulgent' - by frequent intakes of added salt, sugar, alcohol and pickled food, 'diversified-eating' - by frequently consuming food with diversified cooking methods and eating out and 'nutri-health-concerned' - by good food hygiene behaviours and reading food labels. Ethnic differences in eating patterns were observed. Compared with Han, Hui were less likely to exhibit meat-lover or diversified-eating patterns; Tibetans were less likely to have meat-lover or nutri-health-concerned patterns; Mongolians were more likely to have indulgent pattern. BMI was positively associated with meat-lover pattern in both genders (exp(ß): 1·029; 95 % CI: 1·001, 1·058 for men; 1·018; 1·000, 1·036 for women) and negatively associated with nutri-health-concerned pattern in women (0·983; 0·966, 1·000). Mongolians were two times more likely to be overweight/obese than Han (OR: 3·126; 1·688, 5·790). Considerable ethnic differences existed in eating patterns in West China. Mongolians were more likely to be overweight/obese, which was associated with their indulgent eating patterns. Ethnic-specific healthy eating intervention programs are needed.


Assuntos
Dieta , Comportamento Alimentar , Obesidade , Sobrepeso , Adulto , Feminino , Humanos , Masculino , China/epidemiologia , Estudos Transversais , Obesidade/epidemiologia , Etnicidade , População do Leste Asiático
3.
Comput Struct Biotechnol J ; 21: 3466-3477, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38152123

RESUMO

The gut-liver axis is a complex bidirectional communication pathway between the intestine and the liver in which microorganisms and their metabolites flow from the intestine through the portal vein to the liver and influence liver function. In a sterile environment, the phenotype or function of the liver is altered, but few studies have investigated the specific cellular and molecular effects of microorganisms on the liver. To this end, we constructed single-cell and spatial transcriptomic (ST) profiles of germ-free (GF) and specific-pathogen-free (SPF) mouse livers. Single-cell RNA sequencing (scRNA-seq) and single-nucleus RNA sequencing (snRNA-seq) revealed that the ratio of most immune cells was altered in the liver of GF mice; in particular, natural killer T (NKT) cells, IgA plasma cells (IgAs) and Kupffer cells (KCs) were significantly reduced in GF mice. Spatial enhanced resolution omics sequencing (Stereo-seq) confirmed that microorganisms mediated the accumulation of Kupffer cells in the periportal zone. Unexpectedly, IgA plasma cells were more numerous and concentrated in the periportal vein in liver sections from SPF mice but less numerous and scattered in GF mice. ST technology also enables the precise zonation of liver lobules into eight layers and three patterns based on the gene expression level in each layer, allowing us to further investigate the effects of microbes on gene zonation patterns and functions. Furthermore, untargeted metabolism experiments of the liver revealed that the propionic acid levels were significantly lower in GF mice, and this reduction may be related to the control of genes involved in bile acid and fatty acid metabolism. In conclusion, the combination of sc/snRNA-seq, Stereo-seq, and untargeted metabolomics revealed immune system defects as well as altered bile acid and lipid metabolic processes at the single-cell and spatial levels in the livers of GF mice. This study will be of great value for understanding host-microbiota interactions.

4.
Environ Pollut ; 333: 122085, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37348700

RESUMO

Maternal metal(loid)s exposure has been related to preterm birth (PTB), but the results are still inconclusive. Previous studies have mainly discussed the harmful metal(loid)s, neglecting beneficial ones. We examined the association of maternal metal(loid)s with PTB and gestational age (GA) in a birth cohort from the Tibetan Plateau. We measured 29 metal(loid)s in urine samples from 1081 pregnant women in the third trimester. Information regarding demographics, socioeconomic status, diet, medication, and lifestyle was collected through standardized interviews. The associations of single metal(loid)s with PTB or GA were evaluated using a generalized linear mixed-effects model or linear mixed-effects model. Elastic net and Bayesian kernel machine regressions were used to explore the joint associations. Magnesium (Mg), Copper (Cu), and Tin (Sn) were the main "harmful" metal(loid)s positively and negatively associated with PTB or GA, respectively. Mg was the dominant "harmful" metal(loid)s associated with PTB in a J-shape. A one-fold increase in Mg was associated with a 38% increased risk of PTB [OR (95% CI) = 1.38 (1.15, 1.65), PFDR<0.05] and 0.17 weeks shortening of GA [ß (95% CI) = -0.25 (-0.35, -0.14), PFDR<0.05]. Cesium (Cs), rubidium (Rb), and Molybdenum (Mo) were the main "beneficial" metals. Cs dominated the "beneficial" associations and was negatively associated with PTB in a linear manner. A one-fold increase in Cs was associated with a 67% decreased risk of PTB [OR (95% CI) = 0.43 (0.27, 0.67), PFDR<0.05] and 0.24 weeks of prolonged GA [ß (95% CI) = 0.35 (0.13, 0.56), PFDR<0.05]. Ethnicity and living altitude modified the association of Mg and Cu with PTB or GA. In conclusion, Maternal urinary metal(loid)s were bi-directionally associated with PTB in a population in the Tibetan Plateau. Mg and Cs were the dominant "harmful" and "beneficial" metal(loid)s, respectively.


Assuntos
Nascimento Prematuro , Humanos , Gravidez , Feminino , Recém-Nascido , Nascimento Prematuro/epidemiologia , Estudos de Coortes , Tibet/epidemiologia , Teorema de Bayes , Magnésio
5.
J Genet Genomics ; 50(9): 688-701, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37156441

RESUMO

Gut microbes exhibit complex interactions with their hosts and shape an organism's immune system throughout its lifespan. As the largest secondary lymphoid organ, the spleen has a wide range of immunological functions. To explore the role of microbiota in regulating and shaping the spleen, we employ scRNA-seq and Stereo-seq technologies based on germ-free (GF) mice to detect differences in tissue size, anatomical structure, cell types, functions, and spatial molecular characteristics. We identify 18 cell types, 9 subtypes of T cells, and 7 subtypes of B cells. Gene differential expression analysis reveals that the absence of microorganisms results in alterations in erythropoiesis within the red pulp region and congenital immune deficiency in the white pulp region. Stereo-seq results demonstrate a clear hierarchy of immune cells in the spleen, including marginal zone (MZ) macrophages, MZ B cells, follicular B cells and T cells, distributed in a well-defined pattern from outside to inside. However, this hierarchical structure is disturbed in GF mice. Ccr7 and Cxcl13 chemokines are specifically expressed in the spatial locations of T cells and B cells, respectively. We speculate that the microbiota may mediate the structural composition or partitioning of spleen immune cells by modulating the expression levels of chemokines.


Assuntos
Análise da Expressão Gênica de Célula Única , Baço , Camundongos , Animais , Baço/metabolismo , Linfócitos B , Quimiocinas/metabolismo , Imunidade
6.
Int J Biol Macromol ; 242(Pt 1): 124678, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37141972

RESUMO

Plutella xylostella has evolved resistance to Bacillus thuringiensis Cry1Ac toxin over a long evolutionary period. Enhanced immune response is an important factor in insect resistance to a variety of insecticides, and whether phenoloxidase (PO), an immune protein, is involved in resistance to Cry1Ac toxin in P. xylostella remains unclear. Here, spatial and temporal expression patterns showed that prophenoloxidase (PxPPO1 and PxPPO2) in the Cry1S1000-resistant strain was more highly expressed in eggs, 4th instar, head, and hemolymph than those in G88-susceptible strain. The results of PO activity analysis showed that after treatment with Cry1Ac toxin PO activity was about 3 times higher than that before treatment. Furthermore, knockout of PxPPO1 and PxPPO2 significantly increased the susceptibility to Cry1Ac toxin. These findings were further supported by the knockdown of Clip-SPH2, a negative regulator of PO, which resulted in increased PxPPO1 and PxPPO2 expression and Cry1Ac susceptibility in the Cry1S1000-resistant strain. Finally, the synergistic effect of quercetin showed that larval survival decreased from 100 % to <20 % compared to the control group. This study will provide a theoretical basis for the analysis of immune-related genes (PO) genes involved in the resistance mechanism and pest control of P. xylostella.


Assuntos
Bacillus thuringiensis , Mariposas , Animais , Bacillus thuringiensis/genética , Mariposas/metabolismo , Endotoxinas/metabolismo , Toxinas de Bacillus thuringiensis/metabolismo , Larva , Monofenol Mono-Oxigenase/metabolismo , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/farmacologia , Proteínas Hemolisinas/metabolismo , Proteínas de Bactérias/metabolismo
7.
Sensors (Basel) ; 21(21)2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34770650

RESUMO

The use of optical fiber probe in two-phase flow measurements is very frequently encountered, especially in the applications of chemical engineering and petroleum industries. In this work, the influence of bubble piercing signals caused by bubble deformation is studied experimentally using a laboratory-prepared wedge-shaped fiber probe in a lab-scale gas-liquid flow generator. A three-dimensional simulation model is established to study the influence of bubble deformation on the piercing signals. A theoretical analysis of the characteristics of the pre-signal influenced by the bubble deformations is undertaken for a wide range of different modeled bubble shapes. Combining the experimental and simulation results, a promising analytical method to estimate the bubble shapes by analyzing the characteristics of pre-signals is proposed. The results of this investigation demonstrate that it is possible to estimate the bubble shapes before the fiber probe contacts the bubble surface. The method developed in this investigation is therefore highly promising for reducing errors caused by deformation during the probe piercing process.

8.
Appl Opt ; 60(6): 1660-1666, 2021 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-33690509

RESUMO

A conical tip-shaped plastic optical fiber sensor for gas-liquid flow measurement is described. Experimental results show that a distinctive spike signal occurs before the output signal when using a conventional conical fiber probe, whereas this spike signal was greatly suppressed when a cleaved probe is used. A full simulation is implemented based on a three-dimensional ray-tracing method providing a means of comparison with theoretical analysis. The results show that an appropriately cleaved tip provides a promising method of enhancing the bubble measurement signal-to-noise ratio.

9.
J Opt Soc Am A Opt Image Sci Vis ; 37(10): 1687-1694, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33104616

RESUMO

A laboratory-prepared wedge-shaped fiber probe using step-index multimode plastic optical fiber was described and tested in a lab-scale gas-liquid flow generator. A three-dimensional model was established in order to fully simulate the process of bubble piercing by the optical fiber probe. A theoretical analysis of the luminous intensity distribution of the light transmission in the process of bubble piercing was undertaken under conditions of different relative positions between the fiber probe and the bubble axis. Using this analytical method, it was possible to accurately define the range of the central region of the bubble where the presignal appeared.

10.
Mol Med Rep ; 13(2): 1269-74, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26648013

RESUMO

Epigenetic gene silencing due to promoter methylation is observed in human neoplasia, including lymphoma and certain cancer types. One important target for gene methylation analysis in non-Hodgkin lymphoma (NHL) is inhibitor of DNA binding 4 (ID4). The present study aimed to investigate the gene methylation status of ID4, the expression of ID4 protein and the effect of demethylating agent 5-aza-2'-deoxycytosine (CdR) in the Raji human Burkitt's lymphoma cell line in vitro. Following assessment of the inhibition of Raji cell growth by various concentrations of CdR, the effects of CdR on the expression of ID4 protein were assessed using the immunocytochemical streptavidin-peroxidase method and semi-quantitative analysis, while apoptosis and cell cycle were determined by flow cytometry. The ID4 gene methylation status of Raji cells was tested using methylation-specific polymerase chain reaction analysis. ID4 was methylated and its protein expression was low in the control group, while ID4 was partly or completely demethylated and its protein expression was upregulated in Raji cells treated with CdR. In addition, CdR induced apoptosis and cell cycle arrest in Raji cells in a dose- and time-dependent manner. These results demonstrated that ID4 is hypermethylated and its protein expression is low in Burkitt's lymphoma cells, while CdR reversed the abnormal DNA methylation and induced re-expression of ID4 protein. Hypermethylation of ID4 promotes the proliferation of Burkitt's lymphoma cells; ID4 may function as a tumor suppressor and can be targeted with demethylating compounds such as CdR for the treatment of Burkitt's lymphoma.


Assuntos
Linfoma de Burkitt/genética , Proliferação de Células/genética , Metilação de DNA/genética , Proteínas Inibidoras de Diferenciação/genética , Apoptose/genética , Azacitidina/administração & dosagem , Azacitidina/análogos & derivados , Linfoma de Burkitt/patologia , Ciclo Celular/genética , Linhagem Celular Tumoral , Decitabina , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inativação Gênica , Genes Supressores de Tumor , Humanos , Proteínas Inibidoras de Diferenciação/biossíntese , Regiões Promotoras Genéticas
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