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1.
Epilepsy Behav Rep ; 26: 100662, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38590545

RESUMO

Traumatic brain injury (TBI) patients are recommended to receive anti-seizure medication (ASM) as posttraumatic seizure (PTS) prophylaxis. However, the utilization of ASM, including the prescription patterns and associated clinical characteristics, is limited in Taiwan. Thus, this study aimed to investigate the ASM trends and clinical characteristics. This retrospective cohort study enrolled TBI patients who received levetiracetam, phenytoin, and valproic acid during hospitalization using the National Health Insurance Research Database between 2012 and 2019. The primary outcome was the trend of the ASMs based on the index year. The duration of levetiracetam prescription was categorized as short-term (seven days or less) or long-term (more than seven days). Logistic regression identified the factors associated with long-term usage. A total of 64,461 TBI patients were included. Levetiracetam usage increased yearly, while phenytoin declined. Among the levetiracetam users, 5681 (30.38%) were short-term users, and 13,016 (69.62%) were long-term users. Diagnoses of contusions, intracranial hemorrhage, other intracranial injuries, receiving operations, and a history of cerebrovascular disease were significantly associated with longer duration. Conclusions This study revealed the rising trend of levetiracetam usage, indicating its potential as an alternative to phenytoin. TBI patients with more severe conditions were more likely to receive longer prescriptions.

2.
Int J Mol Sci ; 24(10)2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37240257

RESUMO

Sugarcane, a C4 plant, provides most of the world's sugar, and a substantial amount of renewable bioenergy, due to its unique sugar-accumulating and feedstock properties. Brazil, India, China, and Thailand are the four largest sugarcane producers worldwide, and the crop has the potential to be grown in arid and semi-arid regions if its stress tolerance can be improved. Modern sugarcane cultivars which exhibit a greater extent of polyploidy and agronomically important traits, such as high sugar concentration, biomass production, and stress tolerance, are regulated by complex mechanisms. Molecular techniques have revolutionized our understanding of the interactions between genes, proteins, and metabolites, and have aided in the identification of the key regulators of diverse traits. This review discusses various molecular techniques for dissecting the mechanisms underlying the sugarcane response to biotic and abiotic stresses. The comprehensive characterization of sugarcane's response to various stresses will provide targets and resources for sugarcane crop improvement.


Assuntos
Saccharum , Transcriptoma , Saccharum/metabolismo , Proteômica , Perfilação da Expressão Gênica , Açúcares/metabolismo , Regulação da Expressão Gênica de Plantas
3.
Nutrients ; 15(10)2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37242208

RESUMO

To help consumers understand the healthfulness of food and make healthy food choices, manufacturers are increasingly providing front-of-package nutrition labels. However, not all types of front-of-package nutrition labels can promote consumers' healthy food purchase behavior. We explored the impact of front-of-package nutrition label type on the consumer purchase behavior of healthy food through three experiments. The results show that evaluative (vs. objective) front-of-package nutrition labels can improve consumer purchase intention and willingness to pay for healthy food. The spokesperson type moderates the influence of front-of-package nutrition labels on consumers' healthy food purchase behavior. Specifically, when the spokesperson type is a typical consumer, consumers are more willing to buy healthy foods with evaluative nutrition labels than those with objective nutrition labels. When the spokesperson type is a star, consumers are more willing to buy healthy food with objective nutrition labels (vs. evaluative nutrition labels). Finally, this study provides feasible suggestions for marketers to select appropriate front-of-package nutrition labels.


Assuntos
Comportamento de Escolha , Rotulagem de Alimentos , Valor Nutritivo , Rotulagem de Alimentos/métodos , Preferências Alimentares , Estado Nutricional , Comportamento do Consumidor
4.
BMC Bioinformatics ; 22(Suppl 5): 637, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36949378

RESUMO

BACKGROUND: Antibiotic resistance has become a global concern. Vancomycin is known as the last line of antibiotics, but its treatment index is narrow. Therefore, clinical dosing decisions must be made with the utmost care; such decisions are said to be "suitable" only when both "efficacy" and "safety" are considered. This study presents a model, namely the "ensemble strategy model," to predict the suitability of vancomycin regimens. The experimental data consisted of 2141 "suitable" and "unsuitable" patients tagged with a vancomycin regimen, including six diagnostic input attributes (sex, age, weight, serum creatinine, dosing interval, and total daily dose), and the dataset was normalized into a training dataset, a validation dataset, and a test dataset. AdaBoost.M1, Bagging, fastAdaboost, Neyman-Pearson, and Stacking were used for model training. The "ensemble strategy concept" was then used to arrive at the final decision by voting to build a model for predicting the suitability of vancomycin treatment regimens. RESULTS: The results of the tenfold cross-validation showed that the average accuracy of the proposed "ensemble strategy model" was 86.51% with a standard deviation of 0.006, and it was robust. In addition, the experimental results of the test dataset revealed that the accuracy, sensitivity, and specificity of the proposed method were 87.54%, 89.25%, and 85.19%, respectively. The accuracy of the five algorithms ranged from 81 to 86%, the sensitivity from 81 to 92%, and the specificity from 77 to 88%. Thus, the experimental results suggest that the model proposed in this study has high accuracy, high sensitivity, and high specificity. CONCLUSIONS: The "ensemble strategy model" can be used as a reference for the determination of vancomycin doses in clinical treatment.


Assuntos
Inteligência Artificial , Vancomicina , Humanos , Antibacterianos , Algoritmos , Creatinina
5.
Int J Mol Sci ; 23(22)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36430189

RESUMO

Sugarcane is the most important sugar crop, contributing ≥80% to total sugar production around the world. Spodoptera frugiperda is one of the main pests of sugarcane, potentially causing severe yield and sugar loss. The identification of key defense factors against S. frugiperda herbivory can provide targets for improving sugarcane resistance to insect pests by molecular breeding. In this work, we used one of the main sugarcane pests, S. frugiperda, as the tested insect to attack sugarcane. Integrated transcriptome and metabolomic analyses were performed to explore the changes in gene expression and metabolic processes that occurred in sugarcane leaf after continuous herbivory by S. frugiperda larvae for 72 h. The transcriptome analysis demonstrated that sugarcane pest herbivory enhanced several herbivory-induced responses, including carbohydrate metabolism, secondary metabolites and amino acid metabolism, plant hormone signaling transduction, pathogen responses, and transcription factors. Further metabolome analysis verified the inducement of specific metabolites of amino acids and secondary metabolites by insect herbivory. Finally, association analysis of the transcriptome and metabolome by the Pearson correlation coefficient method brought into focus the target defense genes against insect herbivory in sugarcane. These genes include amidase and lipoxygenase in amino acid metabolism, peroxidase in phenylpropanoid biosynthesis, and pathogenesis-related protein 1 in plant hormone signal transduction. A putative regulatory model was proposed to illustrate the sugarcane defense mechanism against insect attack. This work will accelerate the dissection of the mechanism underlying insect herbivory in sugarcane and provide targets for improving sugarcane variety resistance to insect herbivory by molecular breeding.


Assuntos
Herbivoria , Saccharum , Animais , Spodoptera/genética , Saccharum/genética , Transcriptoma , Reguladores de Crescimento de Plantas , Metaboloma , Insetos/fisiologia , Grão Comestível/genética , Açúcares , Aminoácidos/genética
6.
Foods ; 11(16)2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36010458

RESUMO

The strategy of food customization has increasingly aroused widespread interest among marketing managers and scholars, but most of them focus on the direct effect of customization on purchase intention. According to the research on self-image-consistent product perceptions, customization may also have an indirect amplification effect. Current research finds food customization will prompt individuals to incorporate their expertise in their perceptions of focal product attributes (taste perception). The findings of two studies demonstrate that food customization and consumer expertise have an interaction effect on consumers' purchase intention. Specifically, consumers with higher (lower) expertise prefer customized food (standard food). Consumers' taste perception mediates the interaction effect between food customization and consumer expertise on purchase intention. Finally, these findings provide guidance for marketing managers to adopt customized strategies.

7.
BMC Genomics ; 23(1): 532, 2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35869434

RESUMO

BACKGROUND: Sugarcane is the most important sugar crop, contributing > 80% of global sugar production. High sucrose content is a key target of sugarcane breeding, yet sucrose improvement in sugarcane remains extremely slow for decades. Molecular breeding has the potential to break through the genetic bottleneck of sucrose improvement. Dissecting the molecular mechanism(s) and identifying the key genetic elements controlling sucrose accumulation will accelerate sucrose improvement by molecular breeding. In our previous work, a proteomics dataset based on 12 independent samples from high- and low-sugar genotypes treated with ethephon or water was established. However, in that study, employing conventional analysis, only 25 proteins involved in sugar metabolism were identified . RESULTS: In this work, the proteomics dataset used in our previous study was reanalyzed by three different statistical approaches, which include a logistic marginal regression, a penalized multiple logistic regression named Elastic net, as well as a Bayesian multiple logistic regression method named Stochastic search variable selection (SSVS) to identify more sugar metabolism-associated proteins. A total of 507 differentially abundant proteins (DAPs) were identified from this dataset, with 5 of them were validated by western blot. Among the DAPs, 49 proteins were found to participate in sugar metabolism-related processes including photosynthesis, carbon fixation as well as carbon, amino sugar, nucleotide sugar, starch and sucrose metabolism. Based on our studies, a putative network of key proteins regulating sucrose accumulation in sugarcane is proposed, with glucose-6-phosphate isomerase, 2-phospho-D-glycerate hydrolyase, malate dehydrogenase and phospho-glycerate kinase, as hub proteins. CONCLUSIONS: The sugar metabolism-related proteins identified in this work are potential candidates for sucrose improvement by molecular breeding. Further, this work provides an alternative solution for omics data processing.


Assuntos
Saccharum , Teorema de Bayes , Análise de Dados , Regulação da Expressão Gênica de Plantas , Fotossíntese , Melhoramento Vegetal , Proteômica , Saccharum/metabolismo , Sacarose/metabolismo , Açúcares/metabolismo
8.
Insects ; 13(6)2022 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-35735837

RESUMO

Chilo sacchariphagus Bojer is an important sugarcane pest globally. Along with genetic modification strategies, the sterile insect technique (SIT) has gained more attention as an environment-friendly method for pest control. The identification of key genes associated with sex determination and differentiation will provide important basic information for this control strategy. As such, the transcriptome sequencing of female and male adults was conducted in order to understand the sex-biased gene expression and molecular basis of sex determination and differentiation in this species. A total of 60,429 unigenes were obtained; among them, 34,847 genes were annotated. Furthermore, 11,121 deferentially expressed genes (DEGs) were identified, of which 8986 were male-biased and 2135 were female-biased genes. The male-biased genes were enriched for carbon metabolism, peptidase activity and transmembrane transport, while the female-biased genes were enriched for the cell cycle, DNA replication, and the MAPK signaling pathway. In addition, 102 genes related to sex-determination and differentiation were identified, including the protein toll, ejaculatory bulb-specific protein, fruitless, transformer-2, sex-lethal, beta-Catenin, sox, gata4, beta-tubulin, cytosol aminopeptidase, seminal fluid, and wnt4. Furthermore, transcription factors such as myb, bhlh and homeobox were also found to be potentially related to sex determination and differentiation in this species. Our data provide new insights into the genetic elements associated with sex determination and differentiation in Chilo sacchariphagus, and identified potential candidate genes to develop pest-control strategies.

9.
Biol Res ; 54(1): 15, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33933166

RESUMO

BACKGROUND: Water stress is one of the serious abiotic stresses that negatively influences the growth, development and production of sugarcane in arid and semi-arid regions. However, silicon (Si) has been applied as an alleviation strategy subjected to environmental stresses. METHODS: In this experiment, Si was applied as soil irrigation in sugarcane plants to understand the mitigation effect of Si against harmful impact of water stress on photosynthetic leaf gas exchange. RESULTS: In the present study we primarily revealed the consequences of low soil moisture content, which affect overall plant performance of sugarcane significantly. Silicon application reduced the adverse effects of water stress by improving the net photosynthetic assimilation rate (Anet) 1.35-18.75%, stomatal conductance to water vapour (gs) 3.26-21.57% and rate of transpiration (E) 1.16-17.83%. The mathematical models developed from the proposed hypothesis explained the functional relationships between photosynthetic responses of Si application and water stress mitigation. CONCLUSIONS: Silicon application showed high ameliorative effects on photosynthetic responses of sugarcane to water stress and could be used for mitigating environmental stresses in other crops, too, in future.


Assuntos
Saccharum , Silício , Desidratação , Fotossíntese , Folhas de Planta , Água
10.
Biol. Res ; 54: 15-15, 2021. ilus, tab, graf
Artigo em Inglês | LILACS | ID: biblio-1505808

RESUMO

BACKGROUND: Water stress is one of the serious abiotic stresses that negatively influences the growth, development and production of sugarcane in arid and semi-arid regions. However, silicon (Si) has been applied as an alleviation strategy subjected to environmental stresses. METHODS: In this experiment, Si was applied as soil irrigation in sugarcane plants to understand the mitigation effect of Si against harmful impact of water stress on photosynthetic leaf gas exchange. RESULTS: In the present study we primarily revealed the consequences of low soil moisture content, which affect overall plant performance of sugarcane significantly. Silicon application reduced the adverse effects of water stress by improving the net photosynthetic assimilation rate (Anet) 1.35-18.75%, stomatal conductance to water vapour (gs) 3.26-21.57% and rate of transpiration (E) 1.16-17.83%. The mathematical models developed from the proposed hypothesis explained the functional relationships between photosynthetic responses of Si application and water stress mitigation. CONCLUSIONS: Silicon application showed high ameliorative effects on photosynthetic responses of sugarcane to water stress and could be used for mitigating environmental stresses in other crops, too, in future.


Assuntos
Silício , Saccharum , Fotossíntese , Água , Folhas de Planta , Desidratação
11.
Biol Res ; 53(1): 47, 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33066819

RESUMO

Nitrogen is the main limiting nutrient after carbon, hydrogen and oxygen for photosynthetic process, phyto-hormonal, proteomic changes and growth-development of plants to complete its lifecycle. Excessive and inefficient use of N fertilizer results in enhanced crop production costs and atmospheric pollution. Atmospheric nitrogen (71%) in the molecular form is not available for the plants. For world's sustainable food production and atmospheric benefits, there is an urgent need to up-grade nitrogen use efficiency in agricultural farming system. The nitrogen use efficiency is the product of nitrogen uptake efficiency and nitrogen utilization efficiency, it varies from 30.2 to 53.2%. Nitrogen losses are too high, due to excess amount, low plant population, poor application methods etc., which can go up to 70% of total available nitrogen. These losses can be minimized up to 15-30% by adopting improved agronomic approaches such as optimal dosage of nitrogen, application of N by using canopy sensors, maintaining plant population, drip fertigation and legume based intercropping. A few transgenic studies have shown improvement in nitrogen uptake and even increase in biomass. Nitrate reductase, nitrite reductase, glutamine synthetase, glutamine oxoglutarate aminotransferase and asparagine synthetase enzyme have a great role in nitrogen metabolism. However, further studies on carbon-nitrogen metabolism and molecular changes at omic levels are required by using "whole genome sequencing technology" to improve nitrogen use efficiency. This review focus on nitrogen use efficiency that is the major concern of modern days to save economic resources without sacrificing farm yield as well as safety of global environment, i.e. greenhouse gas emissions, ammonium volatilization and nitrate leaching.


Assuntos
Agricultura , Monitoramento Ambiental , Nitrogênio/metabolismo , Fertilizantes , Nitratos
12.
Environ Toxicol ; 34(11): 1199-1207, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31294929

RESUMO

Despite intensive research activities, there are still many major knowledge gaps over the potential adverse effects of titanium dioxide nanoparticles (TiO2 -NPs), one of the most widely produced and used nanoparticles, on human cardiovascular health and the underlying mechanisms. In the present study, alkaline comet assay and cytokinesis-block micronucleus test were employed to determine the genotoxic potentials of four sizes (100, 50, 30, and 10 nm) of anatase TiO2 -NPs to human umbilical vein endothelial cells (HUVECs) in culture. Also, the intracellular redox statuses were explored through the measurement of the levels of reactive oxygen species (ROS) and reduced glutathione (GSH) with kits, respectively. Meanwhile, the protein levels of nuclear factor erythroid 2-related factor 2 (Nrf2) were also detected by western blot. The results showed that at the exposed levels (1, 5, and 25 µg/mL), all the four sizes of TiO2 -NPs could elicit an increase of both DNA damage and MN frequency in HUVECs in culture, with a positive dose-dependent and negative size-dependent effect relationship (T100 < T50 < T30 < T10). Also, increased levels of intracellular ROS, but decreased levels of GSH, were found in all the TiO2 -NP-treated groups. Intriguingly, a very similar manner of dose-dependent and size-dependent effect relationship was observed between the ROS test and both comet assay and MN test, but contrary to that of GSH assay. Correspondingly, the levels of Nrf2 protein were also elevated in the TiO2 -NP-exposed HUVECs, with an inversely size-dependent effect relationship. These findings indicated that induction of oxidative stress and subsequent genotoxicity might be an important biological mechanism by which TiO2 -NP exposure would cause detrimental effects to human cardiovascular health.


Assuntos
Dano ao DNA/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Titânio/química , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Glutationa/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Nanopartículas Metálicas/química , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Tamanho da Partícula , Espécies Reativas de Oxigênio/metabolismo , Regulação para Cima/efeitos dos fármacos
13.
BMC Plant Biol ; 19(1): 285, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31253103

RESUMO

BACKGROUND: Sugarcane is a major crop producing about 80% of sugar globally. Increasing sugar content is a top priority for sugarcane breeding programs worldwide, however, the progress is extremely slow. Owing to its commercial significance, the physiology of sucrose accumulation has been studied extensively but it did not lead to any significant practical outcomes. Recent molecular studies are beginning to recognize genes and gene networks associated with this phenomenon. To further advance our molecular understanding of sucrose accumulation, we altered sucrose content of sugarcane genotypes with inherently large variation for sucrose accumulation using a sugarcane ripener, ethylene, and studied their transcriptomes to identify genes associated with the phenomenon. RESULTS: Sucrose content variation in the experimental genotypes was substantial, with the top-performing clone producing almost 60% more sucrose than the poorest performer. Ethylene treatment increased stem sucrose content but that occurred only in low-sugar genotype. Transcriptomic analyses have identified about 160,000 unigenes of which 86,000 annotated genes were classified into functional groups associated with carbohydrate metabolism, signaling, localization, transport, hydrolysis, growth, catalytic activity, membrane and storage, suggesting the structural and functional specification, including sucrose accumulation, occurring in maturing internodes. About 25,000 genes were differentially expressed between all genotypes and treatments combined. Genotype had a dominant effect on differential gene expression than ethylene treatment. Sucrose and starch metabolism genes were more responsive to ethylene treatment in low-sugar genotype. Ethylene caused differential gene expression of many stress-related transcription factors, carbohydrate metabolism, hormone metabolism and epigenetic modification. Ethylene-induced expression of ethylene-responsive transcription factors, cytosolic acid- and cell wall-bound invertases, and ATPase was more pronounced in low- than in high-sugar genotype, suggesting an ethylene-stimulated sink activity and consequent increased sucrose accumulation in low-sugar genotype. CONCLUSION: Ethylene-induced sucrose accumulation is more pronounced in low-sugar sugarcane genotype, and this is possibly achieved by the preferential activation of genes such as invertases that increase sink strength in the stem. The relatively high enrichment of differentially expressed genes associated with hormone metabolism and signaling and stress suggests a strong hormonal regulation of source-sink activity, growth and sucrose accumulation in sugarcane.


Assuntos
Etilenos/farmacologia , Regulação da Expressão Gênica de Plantas , Reguladores de Crescimento de Plantas/farmacologia , Saccharum/fisiologia , Sacarose/metabolismo , Genótipo , Saccharum/crescimento & desenvolvimento , Transcriptoma
14.
Environ Sci Pollut Res Int ; 26(2): 1911-1920, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30460651

RESUMO

Concerns over the health risk of the widely distributed, commonly used silica nanoparticles (SiNPs) are increasing worldwide. Yet, up to now, there are still many major knowledge gaps over the potential adverse effects of SiNP exposure on human cardiovascular health and the underlying mechanisms. In this study, comet assay and micronucleus test were employed to determine the genotoxic potentials of four sizes (10, 25, 50, 100 nm) of SiNPs to human umbilical vein endothelial cells (HUVECs) in culture. The intracellular redox statuses were explored through the determination of the levels of reactive oxygen species (ROS) and reduced glutathione (GSH) with kits, respectively. The protein levels of nuclear factor erythroid 2-related factor 2 (Nrf2) were also detected by Western blot. The results showed that at the administrative levels (1, 5, 25 µg/mL), all the four sizes of SiNPs could induce an increase of both DNA damages and MN frequencies in HUVECs in culture, with a positive dose- and negative size-dependent effect relationship (S100 < S50 < S25 < S10). Also, significantly enhanced levels of intracellular ROS, but decreased levels of GSH, were observed in the SiNP-treated groups. Interestingly, a very similar manner of dose- and size-dependent effect relationship was observed between the ROS test and both comet assay and MN test, but contrary to that of GSH assay. Correspondingly, the levels of Nrf2 protein were also enhanced in the SiNP-treated HUVECs, with a negative size-dependent effect relationship. These results implicated that induction of oxidative stress and subsequent genotoxicity may be an important biological mechanism by which SiNP exposure may affect human cardiovascular health.


Assuntos
Nanopartículas/toxicidade , Dióxido de Silício/toxicidade , Testes de Toxicidade , Dano ao DNA , Células Endoteliais , Humanos , Estresse Oxidativo , Espécies Reativas de Oxigênio
15.
ACS Macro Lett ; 8(7): 852-858, 2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-35619504

RESUMO

The self-assembly of multiblock copolymers generates diverse hierarchical nanostructures and greatly extends the range of microdomain geometries beyond those produced by diblock copolymers. We report the synthesis of a conformationally asymmetric ABC triblock terpolymer in which the end blocks are a mesogen-jacketed liquid crystalline polymer and poly(dimethylsiloxane), respectively, and its self-assembly under mixed solvent vapor annealing forms a range of sphere, cylinder, and perforated lamellar core-shell morphologies, as well as stacked multilevel structures. Sub-7 nm diameter SiOx nanopatterns were generated by selective plasma etching of the small volume fraction Si-containing core block giving a line/space ratio of ∼1:4. Moreover, the conformational asymmetry of this terpolymer leads to zigzag cylinders on a flat substrate and stable cylinder alignment transverse to template sidewalls within lithographically patterned trenches.

16.
Nanoscale ; 11(1): 285-293, 2018 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-30534671

RESUMO

The self-assembly of a high-χ silicon-containing side-chain liquid crystalline block copolymer (LC BCP) in bulk and in thin films is reported, and the structural transition process from the hexagonally packed cylinder (HEX) to the body-centered cubic structure (BCC) in thin films was examined by both reciprocal and real space experimental methods. The block copolymer, poly(dimethylsiloxane-b-11-(4'-cyanobiphenyl-4-yloxy)undecylmethacrylate) (PDMS-b-P(4CNB11C)MA) with a molecular weight of 19.5 kg mol-1 and a volume fraction of PDMS 27% self-assembled in bulk into a hierarchical nanostructure of sub-20 nm HEX cylinders of PDMS with the P(4CNB11C)MA block exhibiting a smectic LC phase with a 1.61 nm period. The structure remained HEX as the P(4CNB11C)MA block transformed to an isotropic phase at ∼120 °C. In the thin films, the PDMS cylindrical microdomains were oriented in layers parallel to the substrate surface. The LC block formed a smectic LC phase which transformed to an isotropic phase at ∼120 °C, and the microphase-separated nanostructure transformed from HEX to BCC spheres at ∼160 °C. The hierarchical structure as well as the dynamic structural transition of the thin films were characterized using in situ grazing-incidence small-angle X-ray scattering and grazing-incidence wide-angle X-ray scattering. The transient morphologies from the HEX to BCC structure in thin films were captured by scanning electron microscopy and atomic force microscopy, and the transition pathway was described.

17.
J Agric Food Chem ; 66(40): 10628-10639, 2018 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-30192539

RESUMO

The roles of microRNAs (miRNAs) related to ethylene response in banana fruits remain unknown because many miRNAs are differentially expressed as the fruit ripens, making the identification of ethylene-responsive miRNAs difficult. Using newly harvested banana fruits (within 5 h after harvest) as material, we found that these fruit did not ripen when treated with 5 µL/L of ethylene for 12 h at 22 °C. Two miRNA libraries were generated from newly harvested banana fruits with and without ethylene treatment and sequenced. In total, 128 known miRNAs belonging to 42 miRNA families were obtained, and 12 novel miRNAs were identified. Among them, 22 were differentially expressed in response to ethylene treatment, among which 6 known miRNAs and their putative targets were validated using qRT-PCR. These putative targets encoded proteins including GATA, ARF, DLC, and AGO, etc. KEGG and GO analyses showed that miRNAs differentially expressed in response to ethylene mainly function in the molecular and biological processes.


Assuntos
Etilenos/farmacologia , MicroRNAs/genética , Musa/efeitos dos fármacos , Reguladores de Crescimento de Plantas/farmacologia , Proteínas de Plantas/genética , Frutas/efeitos dos fármacos , Frutas/genética , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Sequenciamento de Nucleotídeos em Larga Escala , MicroRNAs/metabolismo , Musa/genética , Musa/metabolismo , Proteínas de Plantas/metabolismo
18.
Environ Toxicol ; 33(12): 1221-1228, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30126039

RESUMO

Concerns over the health risk of the widely distributed, commonly used titanium dioxide nanoparticles (nano-TiO2 ) are increasing worldwide. Yet, up-to-now, our understanding in their potential effects on the cardiovascular system is very limited and the toxicological mechanisms are still unclear. In the present study, the CCK-8 assay was performed to determine the cytotoxicity of four sizes (10, 30, 50, and 100 nm) of anatase nano-TiO2 on human umbilical vein endothelial cells (HUVECs) in culture, and the flow cytometry was employed to investigate the potential of these nano-TiO2 to induce the apoptosis of HUVECs. The apoptotic pathway was also probed through the determination of the protein expression and activation of p53, Bax, Bcl-2, caspases-9, -7, -3, and PARP by western blot. The results showed that at the administrative levels (1, 5, 25 µg/mL), all the four sizes of nano-TiO2 could significantly inhibit the viability of HUVECs and elicit significant apoptosis in them, compared with the negative control (P < .05, P < .01). Moreover, the apoptotic rates of HUVECs were increased respectively with the elevating levels and decreasing sizes of the administrative nano-TiO2 , showing a clear dose- and size-dependent effect relationships. Interestingly, the increasing phosphorylation of p53, decreasing ratio of Bcl-2/Bax, and enhancing activation of the downstream proteins caspase-9, -7, -3, and PARP, were also observed with the decreasing sizes of the administrative nano-TiO2 in the western blot, indicating that the intracellular approach of apoptosis, the p53-caspase pathway, is the major way of the nano-TiO2 -mediated apoptosis in HUVECs in culture and that the size is an important parameter that may determine the potential of nano-TiO2 to induce cellular response. In conclusion, these results suggested that high levels of nano-TiO2 exposure may pose potential risks to human cardiovascular health by inducing cardiovascular EC apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Nanopartículas/toxicidade , Titânio/toxicidade , Caspase 9/metabolismo , Caspases/metabolismo , Células Cultivadas , Citoplasma/metabolismo , Células Endoteliais da Veia Umbilical Humana/fisiologia , Humanos , Tamanho da Partícula , Fosforilação , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Titânio/química
19.
Environ Pollut ; 233: 218-225, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29096294

RESUMO

With the growing production and applications of silica nanoparticles (SiNPs), human exposure to these nanoparticles continues to increase. However, the possible hazards that SiNP exposure may pose to human cardiovascular system and the underlying mechanisms remain unclear. In the present study, the flow cytometry was employed to investigate the potential of four sizes (10, 25, 50, 100 nm) of SiNPs to induce the apoptosis of human umbilical vein endothelial cells (HUVECs) in culture. The apoptotic pathway was also explored through the determination of the protein expression and/or activation of p53, Bcl-2, Bax, caspases-9, -7, -3, and PARP by western blot. The results showed that all the four sizes of SiNPs could significantly elicit apoptosis in HUVECs at the tested concentrations (1, 5, 25 µg/mL), compared with the negative control (p < 0.05, p < 0.01). Moreover, the apoptotic rates were increased with the elevating levels and decreasing sizes of administrative SiNPs, showing both dose- and size-dependent effect relationships. Interestingly, the enhancing phosphorylation of p53 protein (Ser15), decreasing ratio of Bcl-2/Bax protein, and elevating activation of the downstream proteins, caspase-9, -7, -3 and PARP, were also observed with the decreasing sizes of tested SiNPs, indicating that the p53-caspase pathway is the main way of the SiNP-mediated apoptosis in HUVECs and that the size is an important parameter that determines the SiNPs' potential to induce cellular response.


Assuntos
Nanopartículas/toxicidade , Dióxido de Silício/toxicidade , Proteína Supressora de Tumor p53/metabolismo , Apoptose/efeitos dos fármacos , Western Blotting , Caspase 9/metabolismo , Caspases , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Tamanho da Partícula , Fosforilação , Proteínas Proto-Oncogênicas c-bcl-2
20.
Chemosphere ; 177: 135-143, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28284960

RESUMO

Exposure to airborne fine particulate matter (PM2.5) is associated with cardiovascular diseases (CVDs). Nevertheless, a comprehensive understanding of the underlying biological mechanisms by which PM2.5 exposure induces or aggravates CVDs remain insufficiently clear. In the present study, the flow cytometry was employed to investigate the apoptosis of human umbilical vein endothelial cells (HUVECs) induced by PM2.5 in culture. The underlying apoptotic pathway was also studied through the determination of the protein expression and activation of p53, Bax, Bcl-2, caspases-9, -7, -3, and PARP by western blot. The results showed that PM2.5 could significantly induce the apoptosis of HUVECs at the tested concentrations (0.2, 1, 5, 25 µg mL-1), compared with the negative control (p < 0.05, p < 0.01). The apoptotic rate of HUVECs increased with the elevating levels of PM2.5 exposure, showing a clear dose-effect relationship. Moreover, the increasing phosphorylation of p53, decreasing ratio of Bcl-2/Bax, and enhancing activation of the downstream proteins caspase-9, -7, -3 and PARP, were also observed with the increasing concentrations of PM2.5 administration in the western blot, indicating that the intracellular approach of apoptosis, the p53-Bax-caspases pathway, is the major way of PM2.5-induced apoptosis in HUVECs. In conclusion, these results suggested that induction of EC apoptosis is an important mechanism by which ambient PM2.5 exposure poses adverse effects on the cardiovascular system.


Assuntos
Poluentes Atmosféricos/farmacologia , Apoptose/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/patologia , Material Particulado/farmacologia , Transdução de Sinais/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/metabolismo , Western Blotting , Caspases/metabolismo , Células Cultivadas , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
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