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1.
J Exp Bot ; 75(5): 1376-1389, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-37935439

RESUMO

Genomic imprinting refers to allele-specific expression of genes depending on parental origin, and it is regulated by epigenetic modifications. Intraspecific allelic variation for imprinting has been detected; however, the intraspecific genome-wide allelic epigenetic variation in maize and its correlation with imprinting variants remain unclear. Here, three reciprocal hybrids were generated by crossing Zea mays inbred lines CAU5, B73, and Mo17 in order to examine the intraspecific conservation of the imprinted genes in the kernel. The majority of imprinted genes exhibited intraspecific conservation, and these genes also exhibited interspecific conservation (rice, sorghum, and Arabidopsis) and were enriched in some specific pathways. By comparing intraspecific allelic DNA methylation in the endosperm, we found that nearly 15% of DNA methylation existed as allelic variants. The intraspecific whole-genome correlation between DNA methylation and imprinted genes indicated that DNA methylation variants play an important role in imprinting variants. Disruption of two conserved imprinted genes using CRISPR/Cas9 editing resulted in a smaller kernel phenotype. Our results shed light on the intraspecific correlation of DNA methylation variants and variation for imprinting in maize, and show that imprinted genes play an important role in kernel development.


Assuntos
Metilação de DNA , Zea mays , Zea mays/metabolismo , Alelos , Impressão Genômica , Endosperma/genética , Endosperma/metabolismo , Regulação da Expressão Gênica de Plantas
2.
BMC Med Educ ; 24(1): 386, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589890

RESUMO

BACKGROUND: Medical students face a heavy burden as they are tasked with acquiring a vast amount of medical knowledge within a limited time frame. Self-directed learning (SDL) has become crucial for efficient and ongoing learning among medical students. However, effective ways to foster SDL ability among Chinese medical students are lacking, and limited studies have identified factors that impact the SDL ability of medical students. This makes it challenging for educators to develop targeted strategies to improve students' SDL ability. This study aims to assess SDL ability among Chinese medical students and examine the effects of career calling and teaching competencies on SDL ability, as well as the possible mechanisms linking them. METHODS: Data were collected from 3614 respondents (effective response rate = 60.11%) using cross-sectional online questionnaires and analyzed using IBM SPSS Statistics 22.0. The questionnaire comprised a Demographic Characteristics Questionnaire, Self-directed Learning Ability Scale (Cronbach's alpha = 0.962), Teaching Competencies Scale, and Career Calling Scale. RESULTS: The average SDL ability score of Chinese medical students was 3.68 ± 0.56, indicating a moderate level of SDL ability. The six factors of the Self-directed Learning Ability Scale-self-reflection, ability to use learning methods, ability to set study plans, ability to set studying objectives, ability to adjust psychological state, and willpower in studying-accounted for 12.90%, 12.89%, 12.39%, 11.94%, 11.34%, and 8.67% of the variance, respectively. Furthermore, career calling was positively associated with SDL learning ability (ß = 0.295, p < 0.001), and SDL learning ability was positively associated with teaching competencies (ß = 0.191, p < 0.01). Simple slope analysis showed that when the level of teaching competencies was higher, the influence of career calling on SDL ability was stronger. CONCLUSIONS: Chinese medical students' SDL ability has room for improvement. Medical students could strengthen their willpower in studying by setting milestones goals with rewards, which could inspire their motivation for the next goals. Teachers should guide students to learn experience to improve students' reflective ability. Educators play a crucial role in bridging the gap between career calling education and SDL ability enhancement, highlighting the significance of optimal teaching competencies. Colleges should focus on strengthening teachers' sense of career calling and teaching competencies.


Assuntos
Educação Médica , Estudantes de Medicina , Humanos , Estudos Transversais , Estudantes de Medicina/psicologia , Currículo , China
3.
Inorg Chem ; 62(31): 12468-12479, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37488692

RESUMO

The self-reduction mechanism in pyrophosphate phosphors is currently explained through nonequivalent substitution for charge compensation. Nevertheless, the impact of oxygen vacancies on the self-reduction enhancement requires further investigation. Herein, heterovalent Ba1-xZn1-yP2O7:xEu2+/3+, yMg phosphors with rigid structures were prepared through conventional solid-phase technology in air. The cation substitution strategy leads to different chemistry electronegativity and adjustable crystal field environments and creates vacancy defects. Crystal structure and component analysis indicate the gradual phase segregation change from BaZnP2O7 to BaMgP2O7 with increasing Mg2+ content. The CIE coordinates that are tuned from (0.514, 0.334) to (0.326, 0.152) and realize color-tunable emission from red-orange to blue-violet can be used as multicolor functional materials. Besides, the phosphor demonstrates its maximum Sa of 0.4725% K-1 (498 K) and Sr of 1.376% K-1 (423 K). These results demonstrate that the phosphors have the potential for contactless optical temperature measurement and anticounterfeiting. This work not only investigates the self-reduction of the Eu3+ → Eu2+ phenomenon but also provides a supplementary explanation and data support to complete the effect of the oxygen vacancy on self-reduction.

4.
Inorg Chem ; 62(46): 19070-19079, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37939251

RESUMO

This research focused on the supramolecular self-assembly of organic fluorescent molecules on organically modified layered silicate minerals to design and prepare layered nanocomposites with excellent fluorescence properties. Aromatic hydrocarbons are hydrophobic and poorly loaded on the hydrophilic surface of layered silicate minerals, but they are easily captured by an organically modified mineral surface. Montmorillonite (MMT) and saponite (SAP), typical 2:1 type layered silicate minerals with different octahedral cations, were modified with the cationic surfactant octadecyl trimethylammonium chloride (OTAC) and loaded with pyrene (an aromatic hydrocarbon dye) with different molar ratios to the cationic surfactant by supramolecular self-assembling to construct fluorescent nanocomposites. The effect of pyrene concentration and the octahedral cation of the 2:1 type layered silicate minerals on photoluminescence properties was investigated. The fluorescence spectra of the nanocomposites prepared under low pyrene concentrations showed two bands at around 400 and 470 nm, corresponding to the monomer and excimer emissions; the band intensity of the excimer shoots up with the increase of pyrene concentration, reflecting different contributions from monomer and dimer species and the formation of radical aggregates. The excellent heat resistance of the layered silicate structure can effectively protect pyrene molecules from external environmental influences.

5.
BMC Med Educ ; 23(1): 657, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37691113

RESUMO

BACKGROUND: Class attendance is important for academic performance. Personal interactions between teachers and students are difficult in large classes; the number of medical undergraduate students in China ranges from dozens to over 100. It is important for teachers to control the teaching process to improve student attendance and participation. METHODS: Two classes of fourth-year undergraduate medical students, with each class comprising 115 students, participated in the study. One class, the trial group, was taught by the block-based teaching method based on cybernetics. This study was conducted with three of the courses in the Introduction to Oncology subject, and the trial group's courses included several blocks. Each block had a test paper that the students responded to immediately in class using the Internet. The teacher obtained feedback from the students when the rate of correct responses to block-test questions was less than 90%. The teacher adjusted the teaching in the following blocks according to the feedback information. The other class, the control group, was taught using the traditional lecture-based teaching method. RESULTS: The average attendance in the trial group was 104/115 (90.43%), and that in the control group was 83/115 (72.17%) (p = 0.0003). The teacher adjusted the teaching three times in the radiotherapy course owing to the complex ideas. After feedback, information on chemotherapy for the upper body was adjusted once, as was that on chemotherapy for the lower body, owing to students' attitudes. The average total score of the trial group was 86.06 ± 17.46 and that of the control group was 80.38 ± 6.97 (p = 0.041). Questionnaire I showed that the trial group students' attendance and participation were better than in the control group. Questionnaire II showed that the block-based teaching method based on cybernetics was approved by the students. CONCLUSIONS: The block-based teaching method based on cybernetics used in medical classes with large numbers of Chinese undergraduate students had positive effects.


Assuntos
Educação de Graduação em Medicina , Estudantes de Medicina , Humanos , Povo Asiático , Cibernética , População do Leste Asiático , Pessoal de Educação , Ensino , Educação de Graduação em Medicina/métodos , Avaliação Educacional
6.
Int J Mol Sci ; 24(5)2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36902194

RESUMO

Heterosis or hybrid vigor refers to the superior phenotypic traits of hybrids relative to their parental inbred lines. An imbalance between the expression levels of two parental alleles in the F1 hybrid has been suggested as a mechanism of heterosis. Here, based on genome-wide allele-specific expression analysis using RNA sequencing technology, 1689 genes exhibiting genotype-dependent allele-specific expression (genotype-dependent ASEGs) were identified in the embryos, and 1390 genotype-dependent ASEGs in the endosperm, of three maize F1 hybrids. Of these ASEGs, most were consistent in different tissues from one hybrid cross, but nearly 50% showed allele-specific expression from some genotypes but not others. These genotype-dependent ASEGs were mostly enriched in metabolic pathways of substances and energy, including the tricarboxylic acid cycle, aerobic respiration, and energy derivation by oxidation of organic compounds and ADP binding. Mutation and overexpression of one ASEG affected kernel size, which indicates that these genotype-dependent ASEGs may make important contributions to kernel development. Finally, the allele-specific methylation pattern on genotype-dependent ASEGs indicated that DNA methylation plays a potential role in the regulation of allelic expression for some ASEGs. In this study, a detailed analysis of genotype-dependent ASEGs in the embryo and endosperm of three different maize F1 hybrids will provide an index of genes for future research on the genetic and molecular mechanism of heterosis.


Assuntos
Vigor Híbrido , Zea mays , Alelos , Zea mays/genética , Genótipo , Fenótipo , Regulação da Expressão Gênica de Plantas , Hibridização Genética
7.
Int J Mol Sci ; 23(23)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36499766

RESUMO

Genomic imprinting is a classic epigenetic phenomenon related to the uniparental expression of genes. Imprinting variability exists in seeds and can contribute to observed parent-of-origin effects on seed development. Here, we conducted allelic expression of the embryo and endosperm from four crosses at 11 days after pollination (DAP). First, the F1 progeny of B73(♀) × Mo17(♂) and the inducer line CAU5 were used as parents to obtain reciprocal crosses of BM-C/C-BM. Additionally, the F1 progeny of Mo17(♀) × B73(♂) and CAU5 were used as parents to obtain reciprocal crosses of MB-C/C-MB. In total, 192 and 181 imprinted genes were identified in the BM-C/C-BM and MB-C/C-MB crosses, respectively. Then, by comparing the allelic expression of these imprinted genes in the reciprocal crosses of B73 and CAU5 (BC/CB), fifty-one Mo17-added non-conserved genes were identified as exhibiting imprinting variability. Fifty-one B73-added non-conserved genes were also identified by comparing the allelic expression of imprinted genes identified in BM-C/C-BM, MB-C/C-MB and MC/CM crosses. Specific Gene Ontology (GO) terms were not enriched in B73-added/Mo17-added non-conserved genes. Interestingly, the imprinting status of these genes was less conserved across other species. The cis-element distribution, tissue expression and subcellular location were similar between the B73-added/Mo17-added conserved and B73-added/Mo17-added non-conserved imprinted genes. Finally, genotypic and phenotypic analysis of one non-conserved gene showed that the mutation and overexpression of this gene may affect embryo and kernel size, which indicates that these non-conserved genes may also play an important role in kernel development. The findings of this study will be helpful for elucidating the imprinting mechanism of genes involved in maize kernel development.


Assuntos
Regulação da Expressão Gênica de Plantas , Zea mays , Zea mays/metabolismo , Endosperma/metabolismo , Impressão Genômica , Sementes/metabolismo
8.
Clin Chem Lab Med ; 59(9): 1479-1500, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-33951758

RESUMO

OBJECTIVES: This updated meta-analysis aimed to assess the diagnostic accuracy of circulating cell-free DNA (cfDNA) in breast cancer (BC). CONTENT: An extensive systematic search was performed in PubMed, Scopus, Embase, and Science Direct databases to retrieve all related literature. Various diagnostic estimates, including sensitivity (SE), specificity (SP), likelihood ratios (LRs), diagnostic odds ratio (DOR), and area under the curve (AUC) of summary receiver operating characteristic (sROC) curve, were also calculated using bivariate linear mixed models. SUMMARY: In this meta-analysis, 57 unique articles (130 assays) on 4246 BC patients and 2,952 controls, were enrolled. For quantitative approaches, pooled SE, SP, PLR, NLR, DOR, and AUC were obtained as 0.80, 0.88, 6.7, 0.23, 29, and 0.91, respectively. Moreover, for qualitative approaches, pooled SE and SP for diagnostic performance were obtained as 0.36 and 0.98, respectively. In addition, PLR was 14.9 and NLR was 0.66. As well, the combined DOR was 23, and the AUC was 0.79. OUTLOOK: Regardless of promising SE and SP, analysis of LRs suggested that quantitative assays are not robust enough neither for BC confirmation nor for its exclusion. On the other hand, qualitative assays showed satisfying performance only for confirming the diagnosis of BC, but not for its exclusion. Furthermore, qualitative cfDNA assays showed a better diagnostic performance in patients at the advanced stage of cancer, which represented no remarkable clinical significance as a biomarker for early detection.


Assuntos
Neoplasias da Mama , Ácidos Nucleicos Livres , Área Sob a Curva , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Feminino , Humanos , Curva ROC , Sensibilidade e Especificidade
9.
Pharmazie ; 75(12): 642-645, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33303057

RESUMO

Chaetoglobosin G (CG) is a fungal secondary metabolite and shows anti-tumor effects. However, the mechanisms behind the anti-tumor effect is still unclear. In this study, we evaluated the anti-proliferation effect of CG on human NSCLC A549 cells and explored the underlying mechanisms. The anti-proliferation effect of CG on A549 cells was evaluated by MTT. The targets of CG were screened through transcriptome sequencing. A flow cytometer was used to detect cell cycle and apoptosis. Western blotting was used to analyze apoptosis, cell cycle and autophagy related protein expression. Our results showed that CG had a dose-dependent inhibitory effect on proliferation of A549 cells. Transcriptome sequencing analysis found that CG obviously induced cell cycle arrest. Flow cytometry analysis and western blot showed that CG induced G2/M arrest with p21 protein upregulation and cyclinB1 protein downregulation. Western blot analysis also indicated that p-EGFR, EGFR, p-MEk and p-ERK protein expressions decreased and autophagy protein LC3II expression increased, indicating that CG can promote autophagy through EGFR/MEK/ERK/LC3 pathway. Moreover, CG can induce apoptosis with bcl-2 protein decrease. In conclusion, this study indicated that CG obviously inhibited A549 cell proliferation, and its mechanism may induce autophagy of A549 cells through EGFR/MEK/ERK/LC3 pathway to upregulate the expression of P21, thus lead to G2/M phase arrest to exert an anti-tumor role.


Assuntos
Autofagia/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Receptores ErbB/metabolismo , Alcaloides Indólicos/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Células A549 , Apoptose/efeitos dos fármacos , Humanos , Transdução de Sinais/efeitos dos fármacos
10.
Molecules ; 24(20)2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31623207

RESUMO

Two novel water soluble heteroglycan (PCp-I and PCp-II) with anti-A549 lung cancer cells activity were isolated from Psoralea corylifolia L. Their average molecular weights were 2.721 × 104 and 2.850 × 104. PCp-I and PCp-II had the same monosaccharide composition, but their molar ratios were different. Based on methylation and NMR spectroscopy, the part structure of PCp-I was identified. The results of scanning electron microscope (SEM) showed that PCp-I had an irregular porous structure and PCp-II was flaky and irregularly curved. The results of thermogravimetry-differential scanning calorimetry (TG-DSC) showed that PCp-I and PCp-II had good thermal stability. Furthermore, PCp-I and PCp-II exhibited significant anti-A549 lung cancer cells activity (IC50 = 64.84 and 126.30 µM) in vitro.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Extratos Vegetais/farmacologia , Polissacarídeos/química , Polissacarídeos/farmacologia , Psoralea/química , Células A549 , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Fenômenos Químicos , Humanos , Espectroscopia de Ressonância Magnética , Metilação , Peso Molecular , Monossacarídeos/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Polissacarídeos/isolamento & purificação , Espectroscopia de Infravermelho com Transformada de Fourier
11.
Molecules ; 24(18)2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31492021

RESUMO

Two new cytochalasans, Chaetomadrasins A (1) and B (2), along with six known analogues (3-8), were isolated from the solid-state fermented culture of desert soil-derived Chaetomium madrasense 375. Their structures were clarified by comprehensive spectroscopic analyses, and the absolute configurations of Compounds 1 and 2 were confirmed by electronic circular dichroism (ECD) and calculated ECD. For the first time, Chaetomadrasins A (1), which belongs to the chaetoglobosin family, is characterized by the presence of all oxygen atoms in the form of Carbonyl. Chaetomadrasin B (2) represents the first example of chaetoglobosin type cytochalasan characterized by a hydroxy unit and carbonyl group fused to the indole ring. Compounds 1 and 2 displayed moderate cytotoxicity against HepG2 human hepatocellular carcinoma cells.


Assuntos
Antineoplásicos/farmacologia , Produtos Biológicos/farmacologia , Chaetomium/química , Citocalasinas/farmacologia , Microbiologia do Solo , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Linhagem Celular , Citocalasinas/química , Citocalasinas/isolamento & purificação , Humanos , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Análise Espectral
12.
Biomed Chromatogr ; : e4279, 2018 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-29752731

RESUMO

A systematic study on the metabolome differences between wild Ophiocordyceps sinensis and artificial cultured Cordyceps militaris was conducted using liquid chromatography-mass spectrometry. Principal component analysis and orthogonal projection on latent structure-discriminant analysis results showed that C. militaris grown on solid rice medium (R-CM) and C. militaris grown on tussah pupa (T-CM) evidently separated and individually separated from wild O. sinensis, indicating metabolome difference among wild O. sinensis, R-CM and T-CM. The metabolome differences between R-CM and T-CM indicated that C. militaris could accommodate to culture medium by differential metabolic regulation. Hierarchical clustering analysis was further performed to cluster the differential metabolites and samples based on their metabolic similarity. The higher content of amino acids (pyroglutamic acid, glutamic acid, histidine, phenylalanine and arginine), unsaturated fatty acid (linolenic acid and linoleic acid), peptides, mannitol, adenosine and succinoadenosine in O. sinensis make it as an excellent choice as a traditional Chinese medicine for invigoration or nutritional supplementation. Similar compositions with O. sinensis and easy cultivation make artificially cultured C. militaris a possible alternative to O. sinensis.

13.
Environ Sci Technol ; 51(11): 5951-5961, 2017 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-28489352

RESUMO

The molecular composition of humic-like substances (HULIS) in different aerosol samples was analyzed using an ultrahigh-resolution mass spectrometer to investigate the influence of biomass burning on ambient aerosol composition. HULIS in background aerosols were characterized with numerous molecular formulas similar to biogenic secondary organic aerosols. The abundance of nitrogen-containing organic compounds (NOC), including nitrogen-containing bases (N-bases) and nitroaromatics, increased dramatically in ambient aerosols affected by crop residue burning in the farm field. The molecular distribution of N-bases in these samples exhibited similar patterns to those observed in smoke particles freshly emitted from lab-controlled burning of straw residues but were significantly different with those observed from wood burning. Signal intensity of the major N-bases correlated well with the atmospheric concentrations of potassium and levoglucosan. These N-bases can serve as molecular markers distinguishing HULIS from crop residue burning with from wood burning. More nitroaromatics were detected in ambient aerosols affected by straw burning than in fresh smoke aerosols, indicating that many of them are formed in secondary oxidation processes as smoke plumes evolve in the atmosphere. This study highlights the significant contribution of crop residue burning to atmospheric NOC. Further study is warranted to evaluate the roles of NOC on climate and human health.


Assuntos
Aerossóis , Nitrogênio , Atmosfera , Biomassa , Substâncias Húmicas , Compostos Orgânicos
14.
Phys Chem Chem Phys ; 18(23): 15545-54, 2016 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-27165439

RESUMO

The lutetium containing nitride apatite Lu5(SiO4)3N was prepared by a solid state reaction at high temperature for the first time. Rietveld refinement indicated that the Lu5(SiO4)3N compound has a hexagonal space group of P63/m with cell parameters a = b = 9.700 Å and c = 7.238 Å. Additionally, the results revealed that there are two distinct lutetium sites in the Lu5(SiO4)3N host lattice, i.e. a Lu(1) site with nine coordination (Wyckoff site 4f) and a Lu(2) site with seven coordination (Wyckoff site 6h). Furthermore, the ratio of the number of Lu atoms in Lu(1) and Lu(2) sites is 3 : 2. The band gap for Lu5(SiO4)3N was determined to be 4.12 eV based on the density functional theory (DFT). In the Ce(3+) doped Lu5(SiO4)3N:0.03Ce(3+) compound, the emission peak centered at 462 nm was observed with the Commission International de I'Eclairage (CIE) coordinates of (0.148, 0.184), indicating blue-emission. Remarkably, in Ce(3+) and Tb(3+) co-doped Lu4.97-y(SiO4)3N:0.03Ce(3+),yTb(3+) compounds, the color-tunability was observed with increasing Tb(3+) co-doping rate on moving from blue at Tb(3+) = 0.00 to green at Tb = 0.09, due to the energy transfer from Ce(3+) to Tb(3+) ions being matched well with the decay curve results. Under the excitation at 359 nm, the absolute quantum efficiency (QE) for Lu5(SiO4)3N:0.03Ce(3+) was determined to be 42.13%. This phosphor material could be a platform for modeling a new phosphor and application in the solid-state lighting field.

15.
Zhongguo Zhong Yao Za Zhi ; 41(19): 3587-3596, 2016 Oct.
Artigo em Zh | MEDLINE | ID: mdl-28925153

RESUMO

Plants of the genus Ceriops (Rhizophoraceae) consist of five species, which were widely distributed in tropical Asia, Eastern Africa and Oceania. So far,phytochemical studies showed that a total of 131 compounds including 120 terpenoids had been isolated from this genus, which exhibited anti-inflammatory, antihyperglycaemic, antitumor, anti-microbial, antioxidant, antifouling and antiviral activities. This article summarized the recent research progress of the chemical compositions and their pharmacological activities from the genus,which could provide reference for the development and utilization of the Ceriops plants.


Assuntos
Medicamentos de Ervas Chinesas/análise , Compostos Fitoquímicos/análise , Rhizophoraceae/química , Extratos Vegetais/análise , Terpenos/análise
16.
Environ Sci Technol ; 48(9): 5264-73, 2014 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-24666379

RESUMO

Using a quasi-experimental opportunity offered by greatly restricted air pollution emissions during the Beijing Olympics compared to before and after the Olympics, we conducted the current study to compare ultrafine particles (UFPs) and fine particles (PM2.5) in their associations with biomarkers reflecting multiple pathophysiological pathways linking exposure and cardiorespiratory events. Number concentrations of particles (13.0-764.7 nm) and mass concentrations of PM2.5 were measured at two locations within 9 km from the residence and workplace of 125 participating Beijing residents. Each participant was measured 6 times for biomarkers of autonomic function (heart rate, systolic and diastolic blood pressures), hemostasis (von Willebrand factor, soluble CD40 ligand, and P-selectin), pulmonary inflammation and oxidative stress (exhaled nitric oxide and exhaled breath condensate pH, malondialdehyde, and nitrite), and systemic inflammation and oxidative stress (urinary malondialdehyde and 8-hydroxy-2'-deoxyguanosine, plasma fibrinogen, and white blood cells). Linear mixed models were used to estimate associations of biomarkers with UFPs and PM2.5 measured 1-7 days prior to biomarker measurements (lags). We found that the correlation coefficient for UFPs at two locations (∼ 9 km apart) was 0.45, and at the same location, the correlation coefficient for PM2.5 vs UFPs was -0.18. Changes in biomarker levels associated with increases in UFPs and PM2.5 were comparable in magnitude. However, associations of certain biomarkers with UFPs had different lag patterns compared to those with PM2.5, suggesting that the ultrafine size fraction (≤ 100 nm) and the fine size fraction (∼ 100 nm to 2.5 µm) of PM2.5 are likely to affect PM-induced pathophysiological pathways independently.


Assuntos
Poluentes Atmosféricos/toxicidade , Pressão Sanguínea/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Material Particulado , Pneumonia/induzido quimicamente , Adulto , Biomarcadores/metabolismo , China , Humanos , Modelos Teóricos , Estresse Oxidativo , Tamanho da Partícula , Adulto Jovem
17.
RSC Adv ; 14(5): 2896-2904, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38239443

RESUMO

Normally, various minerals exist in quartz as inclusions. In this study, methods such as gem microscopy, polarizing microscopy, Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, and electron probe microanalysis (EPMA) were used to systematically study the gemological characteristics and inclusions in green rutilated quartz from Inner Mongolia. Results show that the sample appears green due to the chaotic distribution of green inclusions in the shape of hair filaments. Combined with the chemical composition, the inclusions are Ca-Fe-rich amphiboles with compositions very close to those of the end-member ferro-actinolite. According to the principle of amphibole nomenclature, the inclusions are named ferro-actinolite in the subclass of calc-alkaline amphiboles with a few named ferro-hornblende. Results suggested that the inclusions in green rutilated quartz were formed during the late stage of quartz crystallization. This work provides a new theoretical basis for the study of green rutilated quartz in Huanggangliang, Inner Mongolia.

18.
Nanoscale ; 16(27): 12957-12966, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38898817

RESUMO

The doping of semiconductor materials through some facile and appropriate methods holds significant promise in enhancing the catalytic performance of catalysts. Herein, NiCo2O4/g-C3N4 composite catalysts were synthesized via a high-energy ball milling method. The microstructure and physicochemical characterization of the as-prepared composites confirmed the successful loading of NiCo2O4 nanoparticles onto the g-C3N4 nanosheets. The NiCo2O4/g-C3N4 composites showed excellent catalytic effect under visible light/ultrasonic irradiation, and the efficiency of tetracycline hydrochloride (TCH) degradation reached 90% within 15 min. The optical properties of g-C3N4 nanosheets were improved by doping, and the diffusion of active materials and carrier migration rate were improved by ultrasonic assistance. Possible catalytic mechanisms and potential pathways of the NiCo2O4/g-C3N4 composites for the degradation of TCH triggered by visible light/ultrasonic irradiation were proposed. This study provides a new strategy for energy-assisted photocatalytic degradation of organic pollutants.

19.
Int J Biol Macromol ; 269(Pt 1): 131748, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38670194

RESUMO

Bio-based shape memory materials have attracted wide attention due to their biocompatibility, degradability and safety. However, designing and manufacturing wearable bio-based shape memory films with excellent flexibility and toughness is still a challenge. In this work, silk fibroin substrate with a ß-sheet structure was combined with a tri-block shape memory copolymer to prepare a transparent composited shape memory film. The silk fibroin-based film showed a dual-responsive shape memory function, which can respond to both temperature and water stimuli. This film has a sensitive water-responsive shape memory, which starts deforming after exposure to water for 3 s and fully recovers in 30 s. In addition, the composite film shows highly stretchable (>300 %) and could maintain its high tensile properties after 5 cycles of regeneration. The films also exhibited rapid degradation ability. This study provides new insights for the design of dual-responsive shape memory materials by combining biocompatible matrix and multi-block SMP to simultaneously enhance the mechanical properties, which can be used for intelligent packaging, medical supplies, soft actuators and wearable devices.


Assuntos
Materiais Biocompatíveis , Fibroínas , Fibroínas/química , Materiais Biocompatíveis/química , Materiais Inteligentes/química , Resistência à Tração , Temperatura , Água/química , Bombyx/química
20.
Support Care Cancer ; 21(3): 707-14, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22933129

RESUMO

PURPOSE: The purpose of this article is to evaluate fast-track rehabilitation program and conventional care after esophagectomy using a retrospective controlled cohort study in esophageal cancer patients. METHODS: Fifty-five patients underwent fast-track rehabilitation program and 57 patients underwent conventional care after esophagectomy. Fast-track rehabilitation program was performed to patients who have early movement, epidural analgesia control, fluid infusion volume control and enteral nutrition for early discharge. The other 57 patients underwent conventional care after esophagectomy. The average of hospital stay and complications were calculated in the patients between the two groups. RESULTS: The median length of hospital stay in the patients was significantly shorter after fast-track rehabilitation program than after conventional care (7.7 vs 14.8 day, P < 0.01). The percentage of patients who developed complications was significantly lower 30 day after fast-track rehabilitation program than after conventional care (29.1 vs 47.4%, P < 0.05). 87.3% in patients of the fast-track rehabilitation program group and 54.4% in those of the conventional care group reported excellent to very good satisfaction with their pain control (P = 0.000). CONCLUSIONS: The fast-track rehabilitation program results in fewer complications, less postoperative pain, a reduction in the hospital length of stay, and quicker return to work and normal activities after esophagectomy.


Assuntos
Neoplasias Esofágicas/reabilitação , Esofagectomia/métodos , Complicações Pós-Operatórias/epidemiologia , Estudos de Coortes , Neoplasias Esofágicas/cirurgia , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Dor Pós-Operatória/epidemiologia , Satisfação do Paciente , Estudos Retrospectivos , Retorno ao Trabalho/estatística & dados numéricos , Fatores de Tempo
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