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1.
Front Nutr ; 9: 875360, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35571884

RESUMO

The color and aroma are the significant traits of vegetables and fruits, but the metabolic and molecular mechanisms underlying anthocyanin accumulation and aroma formation remain almost unknown in fennel (Anethum foeniculum L.), which is a crucial vegetable crop and grown widely for aromatic leaves and bulbs. Here, ten major anthocyanins identified and quantified by ultra-high performance liquid chromatography coupled with quadrupole Orbitrap high-resolution mass spectrometry (UHPLC-Q-Orbitrap HRMS) were mainly responsible for the coloration of purple fennel leaf. With the application of GC-MS, it was found that the reduced volatile phenylpropanoids including isoeugenol, trans-isoeugenol, and apiol chiefly account for the characteristic aroma changes of the purple fennel. Moreover, the characteristic anthocyanin coloration and aroma formation in purple fennel were systematically studied with the integrated transcriptomics and metabolomics. The critical genes associated with the biosynthesis and regulation of anthocyanins and volatile phenylpropanoids were isolated and studied carefully in transiently transfected tobacco cells and transgenic tomato plants. Together with the results of UHPLC-Q-Orbitrap HRMS, RT-qPCR, and yeast two hybrid (Y2H), it is proved that the metabolic flux redirection of phenylpropanoid pathway primarily regulated by a functional MYB-bHLH-WD40 complex consisting of AfTT8, AfMYB7, and AfTTG1 accounts for the characteristic anthocyanin coloration and aroma formation in purple fennel leaf. The systematic understanding of the anthocyanin accumulation and aroma formation will assist in the improvement of fennel resource utilization and breeding.

2.
Front Public Health ; 10: 729641, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35419332

RESUMO

Backgrounds: Using the self-reported questionnaire to assess the levels of physical activity (PA) and sedentary behavior (SB) has been a widely recognized method in public health and epidemiology research fields. The selected items of the Health Behavior in School-aged (HBSC) Survey Questionnaire have been used globally for measurements and assessments in PA and SB of children and adolescents. However, there are no comprehensive and critical reviews to assess the quality of studies on reliability and validity of selected items for PA and SB measurement and assessment derived from the HBSC. Thus, this review aimed to critically assess the quality of those studies and summary evidence for future recommendations. Methods: A systematic review protocol was used to search potentially eligible studies on assessing reliability and validity of PA and SB measures of the HBSC questionnaire. electronically academic databases were used. The information on the reliability and validity of the PA and SB measures were extracted and evaluated with well-recognized criteria or assessment tools. Results: After a literature search, six studies were included in this review. The reliability of PA measures of the HBSC questionnaire showed a moderate agreement while the reliability of SB measures showed a great variation across the different items in the different subgroups. The validity of the PA measures had acceptable performance, whereas no studies assess the validity of the SB measures. The included studies all had quality weaknesses on reliability or validity analysis. Conclusions: The PA and SB measures of the HBSC questionnaires were reliable in assessing PA and SB among adolescents. However, a little evidence showed that PA measures are partially valid in assessing PA, but no evidence confirmed the validity of SB measures. The included studies all had methodological weaknesses in examining the reliability and validity of the PA and SB measures, which should be addressed in the future. Further studies are encouraged to use a more standardized study design to examine the reliability and validity of the PA and SB measures in more young populations.


Assuntos
Exercício Físico , Comportamento Sedentário , Adolescente , Criança , Comportamentos Relacionados com a Saúde , Humanos , Reprodutibilidade dos Testes , Inquéritos e Questionários
3.
Front Plant Sci ; 13: 833811, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35463446

RESUMO

The unique flavonoids, quinochalcones, such as hydroxysafflor yellow A (HSYA) and carthamin, in the floret of safflower showed an excellent pharmacological effect in treating cardiocerebral vascular disease, yet the regulating mechanisms governing the flavonoid biosynthesis are largely unknown. In this study, CtACO3, the key enzyme genes required for the ethylene signaling pathway, were found positively related to the flavonoid biosynthesis at different floret development periods in safflower and has two CtACO3 transcripts, CtACO3-1 and CtACO3-2, and the latter was a splice variant of CtACO3 that lacked 5' coding sequences. The functions and underlying probable mechanisms of the two transcripts have been explored. The quantitative PCR data showed that CtACO3-1 and CtACO3-2 were predominantly expressed in the floret and increased with floret development. Subcellular localization results indicated that CtACO3-1 was localized in the cytoplasm, whereas CtACO3-2 was localized in the cytoplasm and nucleus. Furthermore, the overexpression of CtACO3-1 or CtACO3-2 in transgenic safflower lines significantly increased the accumulation of quinochalcones and flavonols. The expression of the flavonoid pathway genes showed an upward trend, with CtCHS1, CtF3H1, CtFLS1, and CtDFR1 was considerably induced in the overexpression of CtACO3-1 or CtACO3-2 lines. An interesting phenomenon for CtACO3-2 protein suppressing the transcription of CtACO3-1 might be related to the nucleus location of CtACO3-2. Yeast two-hybrid (Y2H), glutathione S-transferase (GST) pull-down, and BiFC experiments revealed that CtACO3-2 interacted with CtCSN5a. In addition, the interactions between CtCSN5a and CtCOI1, CtCOI1 and CtJAZ1, CtJAZ1 and CtbHLH3 were observed by Y2H and GST pull-down methods, respectively. The above results suggested that the CtACO3-2 promoting flavonoid accumulation might be attributed to the transcriptional activation of flavonoid biosynthesis genes by CtbHLH3, whereas the CtbHLH3 might be regulated through CtCSN5-CtCOI1-CtJAZ1 signal molecules. Our study provided a novel insight of CtACO3 affected the flavonoid biosynthesis in safflower.

4.
J Environ Sci (China) ; 118: 32-45, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35305771

RESUMO

External carbon source addition is one of the effective methods for the treatment of wastewater with low carbon to nitrogen ratio (C/N). Compared with fast-release liquid carbon sources, slow-release solid carbon sources are more suitable for the denitrification process. A novel slow-release solid carbon source (corncob-polyvinyl alcohol sodium alginate- poly-caprolactone, i.e. CPSP) was prepared using corn cob (CC) and poly-caprolactone with polyvinyl alcohol sodium alginate as hybrid scaffold. The physical properties and carbon release characteristics of CPSP and three other carbon sources were compared. CPSP had stable framework and good carbon release performance, which followed the second order release equation. The formic acid, acetic acid, propionic acid and butyric acid released from CPSP accounted for 8.27% ± 1.66 %, 56.48% ± 3.71 %, 18.46% ± 2.69% and 16.79% ± 3.02% of the total released acids respectively. The start-up period of CPSP was shorter than that of the other carbon sources in denitrification experiment, and no COD pollution was observed in the start-up phase (25-72 h) and stable phase (73-240 hr). The composition and structure of the dissolved organic compounds released by CPSP and other carbon sources were analyzed by UV-Vis absorption spectroscopy and three-dimensional fluorescence spectroscopy, which indicated that CPSP was more suitable for denitrification than the other studied carbon sources.


Assuntos
Carbono , Desnitrificação , Carbono/química , Nitrogênio/química , Águas Residuárias/química
5.
PLoS Genet ; 18(3): e1010077, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35245283

RESUMO

Ovule initiation determines the maximum ovule number and has great impact on seed number and yield. However, the regulation of ovule initiation remains largely elusive. We previously reported that most of the ovule primordia initiate asynchronously at floral stage 9 and PINFORMED1 (PIN1) polarization and auxin distribution contributed to this process. Here, we further demonstrate that a small amount of ovule primordia initiate at floral stage 10 when the existing ovules initiated at floral stage 9 start to differentiate. Genetic analysis revealed that the absence of PIN3 function leads to the reduction in pistil size and the lack of late-initiated ovules, suggesting PIN3 promotes the late ovule initiation process and pistil growth. Physiological analysis illustrated that, unlike picloram, exogenous application of NAA can't restore these defective phenotypes, implying that PIN3-mediated polar auxin transport is required for the late ovule initiation and pistil length. qRT-PCR results indicated that the expression of SEEDSTICK (STK) is up-regulated under auxin analogues treatment while is down-regulated in pin3 mutants. Meanwhile, overexpressing STK rescues pin3 phenotypes, suggesting STK participates in PIN3-mediated late ovule initiation possibly by promoting pistil growth. Furthermore, brassinosteroid influences the late ovule initiation through positively regulating PIN3 expression. Collectively, this study demonstrates that PIN3 promotes the late ovule initiation and contributes to the extra ovule number. Our results give important clues for increasing seed number and yield of cruciferous and leguminous crops.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos/metabolismo , Proteínas de Domínio MADS/genética , Óvulo Vegetal/genética
6.
Exp Cell Res ; 415(1): 113112, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35346671

RESUMO

Chemoresistance contributes to poor survival and high relapse risk in acute myeloid leukemia (AML). As a pro-inflammatory cytokine, interleukin-6 (IL-6) plays a vital role in the chemoresistance of malignancies. However, the underlying mechanisms of chemoresistance in AML have not been widely studied. Lipid metabolism, which contributes to chemoresistance in AML, is enhanced by IL-6 in skeletal muscle cells. We hypothesized that IL-6 promotes the chemoresistance of AML by promoting lipid metabolism. Based on the positive correlation between IL-6 receptor expression and the cellular response to exogenous IL-6, we performed Gene Ontology analysis of a dataset consisting the information of 151 AML patients from The Cancer Genome Atlas. We found that lipid transport-associated genes were upregulated in the high IL-6 receptor expression group. Additionally, IL-6 promoted fatty acid (FA) uptake in both AML cell lines and primary AML cells. Inhibition of FA uptake by sulfo-N-succinimidyl oleate repressed IL-6-induced chemoresistance. Western blotting, quantitative polymerase chain reaction, and chromatin immunoprecipitation assays indicated that IL-6 promoted CD36 expression at both the mRNA and protein levels through stat3 signaling. Knockout of CD36 or stat3 repressed IL-6-induced FA uptake and chemoresistance. Furthermore, in five human AML samples, we validated that compared to CD36-cells, CD36+ primary AML cells were less sensitive to cytosine arabinoside (Ara-c) and that blockade of CD36 re-sensitized CD36+ AML cells to Ara-c. Mice injected with CD36 knockout cells followed by treatment with Ara-c showed markedly decreased leukemia burden and prolonged survival in vivo. Finally, treatment with the CD36 antibody in combination with Ara-c exhibited synergistic effects in vivo. In conclusion, IL-6 promotes chemoresistance in AML through the stat3/CD36-mediated FA uptake. Blockade of CD36 improved the effect of Ara-c, representing a promising strategy for AML therapy.


Assuntos
Interleucina-6 , Leucemia Mieloide Aguda , Animais , Citarabina/metabolismo , Citarabina/farmacologia , Resistencia a Medicamentos Antineoplásicos , Ácidos Graxos , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Camundongos , Camundongos Knockout , Receptores de Interleucina-6
7.
Artigo em Inglês | MEDLINE | ID: mdl-35162238

RESUMO

OBJECTIVE: The purpose of this meta-analysis was to examine the effects of physical activity (PA) on cognition and activities of daily living in adults with Alzheimer's Disease (AD). METHODS: Six electronic databases (MEDLINE, CINAHL, PsycArticles, SPORTDiscus, EMBASE and CNKI) were used to search for potential studies from inception until October 2021. Randomized controlled trials (RCTs) investigating the effect of physical activity (PA) on cognition and activities of daily living in AD patients compared to a control condition were included. The effect sizes were synthesized using a random effects model with a 95% confidence interval (CI). RESULTS: Sixteen articles including 945 participants (aged 70 to 88 years, 34.6% male) met the inclusion criteria. The pooled effect sizes demonstrated that PA intervention was associated with significant improvements in global cognition (Standard Mean Difference (SMD) = 0.41, 95% CI [0.24, 0.58], p < 0.01) and activities of daily living (SMD = 0.56, 95% CI [0.32, 0.79], p < 0.01) in AD patients. Subgroup analyses suggested that PA for 3-4 times per week for 30-45 min for more than 12 weeks had a relatively strong effect on improving global cognition in AD patients. The sensitivity analysis showed robust results. CONCLUSIONS: The findings from the current meta-analysis suggested that AD patients can improve their global cognition and Activities of Daily Living (ADL) through engaging in aerobic and mixed exercise (aerobic and anaerobic exercise).


Assuntos
Atividades Cotidianas , Doença de Alzheimer , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/terapia , Cognição , Exercício Físico , Feminino , Humanos , Masculino , Ensaios Clínicos Controlados Aleatórios como Assunto
8.
Int J Mol Sci ; 23(1)2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-35008936

RESUMO

K-homologous (KH) family is a type of nucleic acid-binding protein containing the KH domain and has been found to affect splicing and transcriptional regulation. However, KH family genes haven't been investigated in plant species systematically. In this study, we identified 30 genes that belonged to the KH family based on HMM of the KH domain in Arabidopsis thaliana. Phylogenetic tree analysis showed that the KH family is grouped into three subgroups. Synteny analysis showed that AtKH9 and AtKH29 have the conserved synteny relationship between A. thaliana and the other five species. The AtKH9 and AtKH29 were located in the cytoplasm and nucleus. The seed germination rates of the mutants atkh9 and atkh29 were higher than wild-type after abscisic acid (ABA) and salicylic acid (SA) treatments. In addition, the expression of ABA-related genes, such as ABRE-binding factor 2 (ABF2), ABRE-binding factor 4 (ABF4), and delta 1-pyrroline-5-carboxylate synthase (P5CS), and an SA-related gene pathogenesis-related proteins b (PR1b) were downregulated after ABA and SA treatments, respectively. These results suggested that atkh9 and atkh29 mutants inhibit the effect of ABA and SA on seed germination. In conclusion, our results provide valuable information for further exploration of the function of KH family genes and propose directions and ideas for the identification and characterization of KH family genes in other plants.


Assuntos
Ácido Abscísico/metabolismo , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , RNA-Seq , Ácido Salicílico/metabolismo , Arabidopsis/genética , Filogenia
9.
Biomed Mater ; 17(2)2022 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-35073528

RESUMO

Lithium disilicate (Li2Si2O5) glass-ceramic is a commonly used dental ceramic material. In this study, Li2Si2O5whiskers were prepared by the hydrothermal method, mixed with Li2Si2O5glass powders, and Li2Si2O5whisker-reinforced glass-ceramics were prepared by reaction sintering. The biosafety of the new Li2Si2O5glass-ceramics were evaluated byin vitrocytotoxicity, hemolysis, oral mucosal irritation, acute systemic toxicity, and subacute systemic toxicity (oral route) tests according to ISO 7405/ISO 10993 standards. The cytotoxicity test results showed that the cell growth of the experimental group was good, and the cell number and morphology were not significantly different from those of the blank group (P> 0.05). The toxicity grading for both experimental and blank control groups were 0. The hemolysis rate of the material was 1.25%, which indicated that it did not cause hemolytic reaction. The material was non-irritating to the oral mucosa. In acute systemic toxicity test, animals in the experimental group showed increased body weight, moved freely, with no signs of poisoning. The food utilization rate and relative growth rate (change of the weight) of rats in the subacute systemic toxicity test were not statistically different from those of the control group (P> 0.05). Preliminary evaluation of the biosafety of the Li2Si2O5whisker-reinforced glass-ceramics showed that it met the existing regulatory standards, and further biosafety experiments can be conducted, following which the material may be expected to be applied in clinical practice.


Assuntos
Contenção de Riscos Biológicos , Vibrissas , Animais , Cerâmica/toxicidade , Porcelana Dentária , Teste de Materiais , Ratos , Propriedades de Superfície
10.
J Integr Plant Biol ; 64(3): 702-716, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34837335

RESUMO

Ovule initiation is a key step that strongly influences ovule number and seed yield. Notably, mutants with enhanced brassinosteroid (BR) and cytokinin (CK) signaling produce more ovules and have a higher seed number per silique (SNS) than wild-type plants. Here, we crossed BR- and CK-related mutants to test whether these phytohormones function together in ovule initiation. We determined that simultaneously enhancing BR and CK contents led to higher ovule and seed numbers than enhancing BR or CK separately, and BR and CK enhanced each other. Further, the BR-response transcription factor BZR1 directly interacted with the CK-response transcription factor ARABIDOPSIS RESPONSE REGULATOR1 (ARR1). Treatments with BR or BR plus CK strengthened this interaction and subsequent ARR1 targeting and induction of downstream genes to promote ovule initiation. Enhanced CK signaling partially rescued the reduced SNS phenotype of BR-deficient/insensitive mutants whereas enhanced BR signaling failed to rescue the low SNS of CK-deficient mutants, suggesting that BR regulates ovule initiation and SNS through CK-mediated and -independent pathways. Our study thus reveals that interaction between BR and CK promotes ovule initiation and increases seed number, providing important clues for increasing the seed yield of dicot crops.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Brassinosteroides/metabolismo , Brassinosteroides/farmacologia , Citocininas/metabolismo , Regulação da Expressão Gênica de Plantas , Óvulo Vegetal/genética , Óvulo Vegetal/metabolismo , Sementes/genética , Sementes/metabolismo
11.
Biomaterials ; 280: 121238, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34810035

RESUMO

Three dimensional (3D) microenvironments more accurately replicate native microenvironments for stem cell maintenance and function compared with two dimensional (2D) microenvironments. However, the molecular mechanisms by which 3D microenvironments regulate stem cell function remain largely unexplored at the single-cell level. Here, using a single-cell analysis and functional analysis, we found not all cell-subpopulations respond to 3D microenvironments based on a systematically 3D gelatin microcarrier culture system we developed for the expansion and function maintenance of hTSPCs. 3D microenvironments alter the cell-subpopulation distribution of human tendon stem/progenitor cells (hTSPCs) by improving the proportion of ICAM1+ITGB8+ and FGF7+CYGB+ subpopulations. We also revealed the activated FGF7 signaling in the two subpopulations is responsible for the enhanced tenogenesis of hTSPCs through cell-cell interactions. The hTSPCs cultured in 3D niche with a specific cell-subpopulation structure exhibited superior stem-cell characteristics and functions both in vitro and in vivo. Together, our study demonstrates that 3D microenvironments can regulate stem-cell function by modulating the critical cell subpopulation and identifies FGF7 as a novel regulator for tenogenic differentiation and tendon regeneration.


Assuntos
Fator 7 de Crescimento de Fibroblastos/metabolismo , Análise de Célula Única , Células-Tronco , Tendões/citologia , Diferenciação Celular , Humanos
12.
Environ Int ; 158: 106977, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34775187

RESUMO

The transient simulation of CO2 and NOX from motor vehicles has essential applications in evaluating vehicular greenhouse gas emissions and pollutant emissions. However, accurately estimating vehicular transient emissions is challenging due to the heterogeneity between different vehicles and the continuous upgrading of vehicle exhaust purification technology. To accurately characterize the transient emissions of motor vehicles, a Super-learner model is used to build CO2 and NOx transient emission models. The actual onboard test data of 9 China VI N2 vehicles were used to train the model, and the test data of another China VI N2 vehicle were selected for further robustness verification. There were significant differences in the emissions between the vehicles, but the constructed transient model could capture the common law of transient emissions from China VI N2 vehicles. The R2 values of CO2 and NOx emission in the test data of the validation vehicle were 0.71 and 0.82, respectively. In addition, to further prove the model's robustness, the training data were synchronously modelled based on the Moves-method. The Super-learner model has a smaller RMSE on the validation set than the model based on the Moves-method, indicating that the Super-learner model has more transient simulation advantages. The marginal contributions of the model characteristics to the model results were analysed by SHapley Additive exPlanation (SHAP) value interpretation, and the marginal contributions of different pollutant characteristic parameters varied. Therefore, when establishing transient models of different pollutants, the selection of the model parameters demands considering the generation and purification process of different pollutants. The present work provides novel insights into the parameter selection, construction, and interpretation of the transient vehicle emission model.


Assuntos
Poluentes Atmosféricos , Poluentes Atmosféricos/análise , Dióxido de Carbono/análise , Monitoramento Ambiental , Gasolina , Veículos Automotores , Emissões de Veículos/análise
13.
Environ Sci Pollut Res Int ; 29(5): 6688-6697, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34462849

RESUMO

The establishment of a non-road construction machinery emission inventory forms the basis for the analysis of pollutant emission characteristics and for the formulation of control policy. We analyzed and investigated data on populations, emission factors, and activity levels for the construction machinery in Tianjin to estimate an emission inventory. Finally, a variety of emission reduction scenarios were used to simulate emission reductions and propose the most effective control policy. The results show that total emissions of CO, HC, NOx, PM10, and PM2.5 from non-road construction machinery in Tianjin of 2018 reached 4180.78, 951.44, 5833.85, 383.92, and 365.70 t, respectively. Forklifts, excavators, and loaders were the three most important emission sources in Tianjin. There are clear differences in the emissions of different districts. Large machinery emissions were mainly distributed across the Binhai New Area, which includes high volumes of port machinery and tractors in Tianjin Port. Based on various emission reduction scenarios, the effect of emission reductions is estimated. The IAD affected the reduction of CO and HC emissions with RR values of 17.6% and 17.3%, respectively, while EMO affected the mitigation of PM10 and PM2.5 emissions and RR values by 18.0% and 18.4%, respectively. The emission reduction control policy for non-road construction machinery is proposed, including the accelerated updating of non-road machinery emission standards; integrating diesel engine research and development institutions to accelerate the development of vehicle after-treatment technology; and establishing a cooperation mechanism for scientific research institutes, government departments, and enterprises in the control of non-road mobile machinery emissions.


Assuntos
Poluentes Atmosféricos , Emissões de Veículos , Agricultura , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Políticas , Emissões de Veículos/análise
14.
J Pharm Sci ; 111(1): 82-87, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34126116

RESUMO

Drug-drug cocrystals, which can regulate physicochemical properties of individual drugs and might produce synergistic therapeutic effects, have drawn growing interest in the pharmaceutical industry. In this study, a novel drug-drug (1:1) cocrystal hydrate of slightly water-soluble dihydromyricetin (DMY) and highly water-soluble pentoxifylline (PTX), DMY-PTX•H2O (1), was prepared by a slurry method. The single-crystal X-ray diffraction results reveal that the cocrystal is formed through hydrogen-bonding interactions between hydroxyl groups of DMY and four acceptors of PTX. The dynamic vapour sorption results indicate that the cocrystal displays reduced hydrophilicity compared with DMY. It is found that cocrystal formation narrows the solubility difference between two parent drugs. The equilibrium solubility of PTX decreases greatly, while that of DMY increases slightly. As a result, DMY and PTX are synchronously and sustainedly released from the cocrystal. Further, a synergistic anti-cancer effect of the cocrystal DMY-PTX•H2O (1) on HepG2 cells in vitro at a drug concentration of 100 µM was discovered. This study brings evidence of cocrystallization as a successful approach for synchronous sustained-release of two drugs with substantially different aqueous solubility.


Assuntos
Pentoxifilina , Cristalização/métodos , Cristalografia por Raios X , Flavonóis , Pentoxifilina/farmacologia , Solubilidade , Difração de Raios X
15.
Sci Total Environ ; 806(Pt 2): 150656, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34597574

RESUMO

Coral bleaching has become a major threat to coral reefs worldwide, but for most coral species little is known about their resilience to environmental changes. We aimed to understand the gene expressional regulation underlying natural bleaching and recovery in Pavona decussata, a dominant species of scleractinian coral in the northern South China Sea. Analyzing samples collected in 2017 from the field revealed distinct zooxanthellae density, chlorophyll a concentration and transcriptomic signatures corresponding to changes in health conditions of the coral holobiont. In the host, normal-looking tissues of partially bleached colonies were frontloaded with stress responsive genes, as indicated by upregulation of immune defense, response to endoplasmic reticulum, and oxidative stress genes. Bleaching was characterized by upregulation of apoptosis-related genes which could cause a reduction in algal symbionts, and downregulation of genes involved in stress responses and metabolic processes. The transcription factors stat5b and irf1 played key roles in bleaching by regulating immune and apoptosis pathways. Recovery from bleaching was characterized by enrichment of pathways involved in mitosis, DNA replication, and recombination for tissue repairing, as well as restoration of energy and metabolism. In the symbionts, bleaching corresponded to imbalance in photosystems I and II activities which enhanced oxidative stress and limited energy production and nutrient assimilation. Overall, our study revealed distinct gene expressional profiles and regulation in the different phases of the bleaching and recovery process, and provided new insight into the molecular mechanisms underlying the holobiont's resilience that may determine the species' fate in response to global and regional environmental changes.


Assuntos
Antozoários , Animais , Antozoários/genética , Clorofila A , Recifes de Corais , Folhas de Planta , Simbiose , Transcriptoma
16.
Sci Total Environ ; 810: 152276, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34902419

RESUMO

To quantify the emission characteristics of large ocean-going ships, onboard measurements were carried out for a large ocean-going vessel using portable emission measurement system (PEMS). The emission factors (EFs) of conventional pollutants and volatile organic compounds (VOCs) were greatly influenced by real-world operating conditions and engine loads. The sulfur dioxide (SO2) and particulate matter (PM) emissions were mainly influenced by fuel type. The particle size distribution basically showed a single peak pattern, with nucleation mode particles as the main particles and the peak particle sizes ranging between 30 nm and 50 nm. The EFs for particle number (PN) ranged from 2.82 × 1016 to 4.49 × 1016 #/kwh. Carbonaceous components accounted for approximately 31.8% to 41.6% of the PM. SO42-, NH4+, Ca2+, Na+, and NO3- were dominant in water-soluble ions, while V and Ni were high-concentration metal elements, with the ratio of V: Ni ranging from 0.17 to 0.33. Increase in driving speed can lead to the increase in VOCs emissions. Our study presented a comprehensive test method with PEMS, which provides a reference for acquiring future real-world EFs. However, only one representative ship in China using a specific fuel was selected for the test, so it is important to characterize a broader range of ships and fuels.


Assuntos
Poluentes Atmosféricos , Emissões de Veículos , Poluentes Atmosféricos/análise , Oceanos e Mares , Tamanho da Partícula , Material Particulado/análise , Navios , Emissões de Veículos/análise
18.
Artigo em Inglês | MEDLINE | ID: mdl-34886142

RESUMO

Ecosystem restoration has been widely concerned with the damage and degradation of ecosystems worldwide. Scientific and reasonable formulations of ecological restoration zoning is the basis for the formulation of an ecological restoration plan. In this study, a restoration zoning index system was proposed to comprehensively consider the ecological problems of ecosystems. The linear weighted function method was used to construct the ecological restoration index (ERI) as an important index of zoning. The research showed that: (1) the ecological restoration zones of the Qilian Mountains can be divided into eight basins, namely the headwaters of the Datong River Basin, the Danghe-Dahaerteng River Basin, the northern confluence area of the Qinghai Lake, the upper Shule River to middle Heihe River, the Oasis Agricultural Area in the northern foothills of the Qilian Mountain, the Huangshui Basin Valley, Aksay (corridor region of the western Hexi Basin), and the northeastern Tsaidam Basin; (2) the restoration index of the eight ecological restoration zones of the Qilian Mountains was between 0.34-0.8, with an average of 0.61 (the smaller the index, the more prominent the comprehensive ecological problem representing the regional mountains, rivers, forests, cultivated lands, lakes, and grasslands, and thus the greater the need to implement comprehensive ecological protection and restoration projects); and (3) the ecological problems of different ecological zones are frequently numerous, and often show the phenomenon of multiple overlapping ecological problems in the same zone.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , China , Planejamento de Cidades , Rios
19.
Front Psychiatry ; 12: 766804, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34858236

RESUMO

Background: Bullying victimization can impose long-lasting impacts on adolescent's current and subsequent well-being. Understanding the correlates of bullying victimization and how to prevent its occurrence is an urgent need. Food insecurity, an indicator of low socioeconomic status, may be related to bullying victimization. However, research on the association between food insecurity and bullying victimization is limited. Using a representative global sample, this study aimed to investigate the association between food insecurity and bullying victimization in adolescents and whether the association varied between country income levels, sexes, and age groups. Methods: Using cross-sectional, school-based data by 170,618 adolescents in 59 countries from the Global School-based Student Health Survey, multivariable logistic regression and meta-analysis were conducted to investigate the overall, country-stratified, sex-stratified, and age-stratified associations. Results: The prevalence of bullying victimization was 33.3%. In the total sample, adolescents with food insecurity showed significantly higher odds for bullying victimization than those without no food insecurity with a pooled odds ratio (OR) being 1.37 (1.28, 1.47). Further, the association was stronger in higher-income countries, females, and older adolescents. Conclusions: Bullying victimization is prevalent among global adolescents with food insecurity being a significant correlate. The identification of adolescents with perceptions of food insecurity and remedying this condition may be important to reduce the prevalence of bullying. This highlights the need to design and implement sex- and age-specific interventions focusing on remedying food insecurity and bullying victimization among in-school adolescents by taking country income levels into account.

20.
Front Public Health ; 9: 766972, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34926387

RESUMO

Objective: The purpose of this research was to investigate the prevalence of lifestyle behaviors and suicide-related behaviors and the association between them using a nationally representative sample of adolescents from the USA. Methods: 13,677 high school students aged 14-18 years were included in this cross-sectional study. The research data were retrieved from the Youth Risk Behavior Surveillance System Survey in 2019. All data on age, sex, grade, race, physical activity, television time, fruit intake, and suicide-related behavior were self-reported by students. Logistic regression models were adopted to examine the association between lifestyle behaviors and the suicide-related behaviors. Results: Students who played video/computer games for ≥2 h had higher risk of suicide attempt (OR = 1.55, 95%CI: 1.30-1.85). Daily sleep duration of ≤8 h was positively associated with considering a suicide attempt (OR = 1.99, 95%CI: 1.62-2.43). In addition, participants who did not engage in any sport team were more likely to report considering a suicide attempt (OR = 1.50, 95%CI: 1.24-1.81). Conclusion: This research suggests that some lifestyle behaviors (e.g., time for video or computer use, sleep duration, sports team participation, regular breakfast intake, and substance use) are associated with increased risk of suicidal behavior and ideation in high school students. To identify the specific effect of multiple lifestyle factors in influencing the risk of suicide-related behaviors in high school students, longitudinal studies are warranted in future.


Assuntos
Comportamento do Adolescente , Ideação Suicida , Adolescente , Estudos Transversais , Humanos , Estilo de Vida , Assunção de Riscos
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