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1.
J Immunol ; 210(9): 1396-1407, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36971684

RESUMO

Posttranslational modifications expand the functions of immune-related proteins, especially during infections. The respiratory glycoprotein, hemocyanin, has been implicated in many other functions, but the role of phosphorylation modification in its functional diversity is not fully understood. In this study, we show that Penaeus vannamei hemocyanin (PvHMC) undergoes phosphorylation modification during bacterial infection. Dephosphorylation of PvHMC mediated by P. vannamei protein phosphatase 2A catalytic increases its in vitro antibacterial activity, whereas phosphorylation by P. vannamei casein kinase 2 catalytic subunit α decreases its oxygen-carrying capacity and attenuates its in vitro antibacterial activity. Mechanistically, we show that Thr517 is a critical phosphorylation modification site on PvHMC to modulate its functions, which when mutated attenuates the action of P. vannamei casein kinase 2 catalytic subunit α and P. vannamei protein phosphatase 2A catalytic, and hence abolishes the antibacterial activity of PvHMC. Our results reveal that phosphorylation of PvHMC modulates its antimicrobial functions in penaeid shrimp.


Assuntos
Hemocianinas , Penaeidae , Animais , Hemocianinas/metabolismo , Penaeidae/metabolismo , Caseína Quinase II/metabolismo , Proteína Fosfatase 2/metabolismo , Antibacterianos/farmacologia , Antibacterianos/metabolismo
2.
Molecules ; 29(6)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38542839

RESUMO

A practical metal-free and additive-free approach for the synthesis of 6/7/8-membered oxacyclic ketone-fused isoxazoles/isoxazolines tetracyclic or tricyclic structures is reported through Csp3-H bond radical nitrile oxidation and the intramolecular cycloaddition of alkenyl/alkynyl-substituted aryl methyl ketones. This convenient approach enables the simultaneous formation of isoxazole/isoxazoline and 6/7/8-membered oxacyclic ketones to form polycyclic architectures by using tert-butyl nitrite (TBN) as a non-metallic radical initiator and N-O fragment donor.

3.
Public Health Nurs ; 41(3): 476-486, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38468509

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is the sixth most common cancer worldwide and the third leading cause of cancer mortality. HCC has high morbidity, high mortality, and low survival rates. Screening is one of the most significant methods of lowering incidence and death while also increasing survival. OBJECTIVES: The aim of this study was to identify the facilitators and barriers to participation in HCC screening among high-risk populations. METHODS: A comprehensive and systematic search was undertaken in PubMed, Web of Science, MEDLINE, EMBACE, EBSCOhost and the Cochrane Library. A combination of synonyms of the keywords including HCC, screening, factors and adherence were used for searching. Studies addressing the facilitators and barriers to HCC screening compliance in at-risk individuals were included. Data were synthesized using Review Manager version 5.4. A random/fixed effects model meta-analysis was performed to estimate the pooled data and expressed with odds ratio (OR) and 95% confidence interval (CI). RESULTS: A total of seven articles met the inclusion criteria. Qualitative (n = 1) and quantitative (n = 6) studies using various types of surgery were conducted. The most commonly mentioned barriers were insufficient knowledge and awareness of HCC screening, unawareness of the necessity for early detection of HCC and lack of physician recommendation. A meta-analysis of seven studies showed that individuals with a family history of HCC increased screening uptake by nearly three times (OR: 2.69, 95% CI: 1.93, 3.75). Other most frequently reported facilitators include age, education level, and perceived risk et al. CONCLUSIONS: Many barriers to HCC screening were found. Meanwhile, this review points out that improving the awareness of high-risk populations toward HCC screening is expected to enhance compliance, thereby promoting early diagnosis of liver cancer, reducing mortality, and alleviating the burden of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/patologia , Incidência
4.
Inorg Chem ; 62(43): 17954-17960, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37856310

RESUMO

The catalytic field aims to decrease reaction barriers, accelerate reaction processes, and enhance the selectivity toward a target product. This study uses first-principles calculations to design a modified direct Z-scheme SnS2/ß-As heterostructure as a potential photocatalyst for overall water splitting. Our previous investigations have demonstrated that the SnS2/ß-As heterostructure can realize a hydrogen evolution reaction (HER) under light, while the oxygen evolution reaction (OER) follows a pathway involving the intermediate HOOH*. Interestingly, by substituting an S atom of SnS2 with a Se or Te atom, the rate-determining step of the OER is significantly reduced from 3.76 eV to 2.56 or 2.22 eV. Moreover, the OER can occur directly without the transition via HOOH*. Isoelectronic doping effectively trades off the adsorption strength of OER intermediates and promotes the OER process. This work highlights the dual benefits of isoelectronic doping, namely lowering the reaction barrier of the rate-determining step and promoting the selectivity of end products. These findings provide insights into the rational design of high-efficiency photocatalysts for water splitting.

5.
Acta Pharmacol Sin ; 44(5): 940-953, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36357669

RESUMO

Dopaminergic neuron degeneration is a hallmark of Parkinson's disease (PD). We previously reported that the inactivation of von Hippel‒Lindau (VHL) alleviated dopaminergic neuron degeneration in a C. elegans model. In this study, we investigated the specific effects of VHL loss and the underlying mechanisms in mammalian PD models. For in vivo genetic inhibition of VHL, AAV-Vhl-shRNA was injected into mouse lateral ventricles. Thirty days later, the mice received MPTP for 5 days to induce PD. Behavioral experiments were conducted on D1, D3, D7, D14 and D21 after the last injection, and the mice were sacrificed on D22. We showed that knockdown of VHL in mice significantly alleviated PD-like syndromes detected in behavioral and biochemical assays. Inhibiting VHL exerted similar protective effects in MPP+-treated differentiated SH-SY5Y cells and the MPP+-induced C. elegans PD model. We further demonstrated that VHL loss-induced protection against experimental parkinsonism was independent of hypoxia-inducible factor and identified the Dishevelled-2 (DVL-2)/ß-catenin axis as the target of VHL, which was evolutionarily conserved in both C. elegans and mammals. Inhibiting the function of VHL promoted the stability of ß-catenin by reducing the ubiquitination and degradation of DVL-2. Thus, in vivo overexpression of DVL-2, mimicking VHL inactivation, protected against PD. We designed a competing peptide, Tat-DDF-2, to inhibit the interaction between VHL and DVL-2, which exhibited pharmacological potential for protection against PD in vitro and in vivo. We propose the therapeutic potential of targeting the interaction between VHL and DVL-2, which may represent a strategy to alleviate neurodegeneration associated with PD.


Assuntos
Proteínas Desgrenhadas , Doença de Parkinson , Proteína Supressora de Tumor Von Hippel-Lindau , Animais , Humanos , Camundongos , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina , beta Catenina/metabolismo , Caenorhabditis elegans/metabolismo , Modelos Animais de Doenças , Proteínas Desgrenhadas/efeitos dos fármacos , Proteínas Desgrenhadas/metabolismo , Dopamina/farmacologia , Neurônios Dopaminérgicos/metabolismo , Mamíferos , Camundongos Endogâmicos C57BL , Neuroblastoma/metabolismo , Doença de Parkinson/metabolismo , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/metabolismo , Ubiquitinação/efeitos dos fármacos , Ubiquitinação/genética , Proteína Supressora de Tumor Von Hippel-Lindau/antagonistas & inibidores , Proteína Supressora de Tumor Von Hippel-Lindau/metabolismo
6.
Environ Res ; 234: 116392, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37302739

RESUMO

Air pollution is one of the leading causes of overall mortality globally. Cooking emissions are a major source of fine particulate matter (PM2.5). However, studies on their potential perturbations on the nasal microbiota as well as their association with respiratory health are lacking. This pilot study aims to assess the environmental air quality among occupational cooks and its associations with nasal microbiota and respiratory symptoms. A total of 20 cooks (exposed) and 20 unexposed controls (mainly office workers), were recruited in Singapore from 2019 to 2021. Information on sociodemographic factors, cooking methods, and self-reported respiratory symptoms were collected using a questionnaire. Personal PM2.5 concentrations and reactive oxygen species (ROS) levels were measured using portable sensors and filter samplers. DNA was extracted from nasal swabs and sequenced using 16s sequencing. Alpha-diversity and beta-diversity were calculated, and between-group variation analysis of species was performed. Multivariable logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for associations between exposure groups and self-reported respiratory symptoms. Higher daily mean PM2.5 (P = 2 × 10-7) and environmental ROS exposure (P = 3.25 × 10-7) were observed in the exposed group. Alpha diversity of the nasal microbiota between the two groups was not significantly different. However, beta diversity was significantly different (unweighted UniFrac P = 1.11 × 10-5, weighted UniFrac P = 5.42 × 10-6) between the two exposure groups. In addition, certain taxa of bacteria were slightly more abundant in the exposed group compared to unexposed controls. There were no significant associations between the exposure groups and self-reported respiratory symptoms. In summary, the exposed group had higher PM2.5 and ROS exposure levels and altered nasal microbiotas as compared to unexposed controls, though further studies are required to replicate these findings in a larger population.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Poluição do Ar , Humanos , Projetos Piloto , Espécies Reativas de Oxigênio/análise , Exposição Ambiental/análise , Material Particulado/toxicidade , Material Particulado/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Gases , Culinária , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise
7.
J Environ Manage ; 339: 117879, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37068399

RESUMO

Nutrients of carbon, nitrogen and water of farmland ecosystem are essential foundation to guarantee crop production, but also environmental flows associated greenhouse gas (GHG), reactive nitrogen (Nr) releases, and water consumption. Their flow characteristics serve as a crucial starting point for creating efficient management practices and mitigation measures. Therefore, the objectives of this study are to quantify the carbon footprint (CF), nitrogen footprint (NF), water footprint (WF), and comprehensive environmental footprint (ComF) of six paddy-upland rotation systems, including fallow-paddy rice (FA-PR), Chinese milk vetch-paddy rice (CMV-PR), wheat-paddy rice (WH-PR), rapeseed-paddy rice (RA-PR), green forage wheat-paddy rice (WF-PR), and vicia faba bean-paddy rice (FB-PR), as well as to analysis their relationships and define driving factors. Results showed that the lowest area-scaled CF of 3.74 t CO2-eq ha-1 were observed in the CMV-PR rotation, which were 41% lower than that for WH-PR (the highest CF, 9.13 t CO2-eq ha-1) when soil carbon change was taken into account. It is of importance that soil carbon sequestration in CMV-PR rotation could offset up to around 57% of its CF, while the WH-PR rotation only offset 25%. The RA-PR rotation had the highest area-scaled NF and WF, which was 1.8 and 1.9 times greater than those of the lowest rotation in FA-PR. In terms of comprehensive environmental effects, the six rotation systems showed the order of FA-PR < CMV-PR < FB-PR < RA-PR < WF-PR < WH-PR, with NH3 volatilization accounting 60.7%-66.7% and blue-green WF for 17.5%-26.6% of the total. Therefore, priority should be given to optimizing N fertilizer application and water consumption for paddy-upland rotation systems. The study also suggested that appropriate inter-annual adjustment of rotation system could contribute to achieving GHG mitigations and Nr losses.


Assuntos
Infecções por Citomegalovirus , Gases de Efeito Estufa , Oryza , Agricultura/métodos , Nitrogênio , Carbono , Água , Ecossistema , Dióxido de Carbono , Solo , Produção Agrícola , Pegada de Carbono , Fertilizantes , China
8.
Public Health Nurs ; 40(5): 782-789, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37177843

RESUMO

INTRODUCTION: Colorectal cancer (CRC) is associated with a high incidence and mortality rate. Fecal occult blood test (FOBT) is effective in the prevention of CRC. OBJECTIVE: This study aimed to assess knowledge and beliefs regarding FOBT-based screening. METHODS: This study used PubMed, Cochrane Library, MEDLINE Complete, and Web of Science to search for articles. Original full-text studies in English language focusing on knowledge and beliefs of FOBT screening were included. RESULTS: A total of 32 articles were included. This study indicated that the population in most studies had inadequate knowledge and lacked beliefs toward FOBT-based screening. Most of the extracted studies showed that less than half of the participants had heard of FOBT-based screening. Six studies showed that less than 50% of participants had knowledge of FOBT age. Three studies found that less than 40% of participants were aware of the screening interval. Some participants perceived the benefits of FOBT-based screening, while others perceived many barriers to the test. CONCLUSION: Participants' knowledge and belief in FOBT-based screening were insufficient. This review highlights the importance of educational programs to increase knowledge and beliefs regarding FOBT-based screening. It is important to include FOBT-based screening in the health care system to promote the secondary prevention of CRC.


Assuntos
Neoplasias Colorretais , Sangue Oculto , Humanos , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/prevenção & controle , Neoplasias Colorretais/epidemiologia , Detecção Precoce de Câncer , Programas de Rastreamento
9.
Zhongguo Zhong Yao Za Zhi ; 48(3): 715-724, 2023 Feb.
Artigo em Zh | MEDLINE | ID: mdl-36872235

RESUMO

In this study, an established ultra-high performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry(UPLC-Q-TOF-MS) method was combined with multivariate statistical analysis to investigate the commonality and difference of main chemical components in the medicinal parts of Paeonia lactiflora from different cultivars; in addition, a high performance liquid chromatography(HPLC) method was established to simultaneously determine the content of eight active components in Paeoniae Radix Alba. Non-targeted analysis was carried out by UPLC-Q-TOF-MS on a Waters ACQUITY UPLC BEH C_(18)(2.1 mm×100 mm, 1.7 µm) column with a gradient elution of 0.1% aqueous formic acid(A)-acetonitrile(B) as the mobile phase at a flow rate of 0.2 mL·min~(-1). The column temperature was 30 ℃, and an electrospray ionization source was used to acquire mass spectrometry data in positive and negative ion modes. According to the accurate molecular weight and fragment ion information provided by multi-stage mass spectrometry and by comparison with reference substances and literature reports, thirty-six identical components were identified in Paeoniae Radix Alba from different cultivars with positive and negative ion modes. In the negative ion mode, two groups of samples were well separated; specifically, seventeen components with significant differences in content were screened and identified, and one component unique in "Bobaishao" was obtained. Quantitative analysis was conducted by high-performance liquid chromatography(HPLC) on an Agilent HC-C_(18)(4.6 mm×250 mm, 5 µm) column with a gradient elution of 0.1% aqueous phosphoric acid(A)-acetonitrile(B) as the mobile phase at a flow rate of 1.0 mL·min~(-1). The column temperature was 30 ℃ and the detection wavelength was at 230 nm. An HPLC method was developed for the simultaneous determination of eight active components(gallic acid, oxypaeoniflorin, catechin, albiflorin, paeoniflorin, galloylpaeoniflorin, 1,2,3,4,6-O-pentagalloylglucose, benzoyl-paeoniflorin) in Paeoniae Radix Albaa from different cultivars. Satisfactory linearity was achieved within the investigated linear ranges and with fine coefficients(r>0.999 0), and the methodological investigation showed that the method had good precision, repeatability and stability. The mean recoveries were 90.61% to 101.7% with RSD of 0.12% to 3.6%(n=6). UPLC-Q-OF-MS provided a rapid and efficient qualitative analytical method for the identification of the chemical components in Paeoniae Radix Alba, and the developed HPLC method was simple, rapid and accurate, which could provide a scientific basis for the evaluation of the germplasm resources and herbal quality of Paeoniae Radix Alba from different cultivars.


Assuntos
Paeonia , Cromatografia Líquida de Alta Pressão , Acetonitrilas
10.
Angew Chem Int Ed Engl ; 62(37): e202306501, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37365143

RESUMO

A palladium-catalyzed reductive difluorocarbene transfer reaction that tames difluorocarbene to couple with two electrophiles has been developed, representing a new mode of difluorocarbene transfer reaction. The approach uses low-cost and bulk industrial chemical chlorodifluoromethane (ClCF2 H) as the difluorocarbene precursor. It produces a variety of difluoromethylated (hetero)arenes from widely available aryl halides/triflates and proton sources, featuring high functional group tolerance and synthetic convenience without preparing organometallic reagents. Experimental mechanistic studies reveal that an unexpected Pd0/II catalytic cycle is involved in this reductive reaction, wherein the oxidative addition of palladium(0) difluorocarbene ([Pd0 (Ln )]=CF2 ) with aryl electrophile to generate the key intermediate aryldifluoromethylpalladium [ArCF2 Pd(Ln )X], followed by reaction with hydroquinone, is responsible for the reductive difluorocarbene transfer.

11.
J Am Chem Soc ; 144(31): 14288-14296, 2022 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-35895322

RESUMO

The application of abundant and inexpensive fluorine feedstock sources to synthesize fluorinated compounds is an appealing yet underexplored strategy. Here, we report a photocatalytic radical hydrodifluoromethylation of unactivated alkenes with an inexpensive industrial chemical, chlorodifluoromethane (ClCF2H, Freon-22). This protocol is realized by merging tertiary amine-ligated boryl radical-induced halogen atom transfer (XAT) with organophotoredox catalysis under blue light irradiation. A broad scope of readily accessible alkenes featuring a variety of functional groups and drug and natural product moieties could be selectively difluoromethylated with good efficiency in a metal-free manner. Combined experimental and computational studies suggest that the key XAT process of ClCF2H is both thermodynamically and kinetically favored over the hydrogen atom transfer pathway owing to the formation of a strong boron-chlorine (B-Cl) bond and the low-lying antibonding orbital of the carbon-chlorine (C-Cl) bond.


Assuntos
Alcenos , Boranos , Alcenos/química , Aminas , Cloro , Clorofluorcarbonetos , Clorofluorcarbonetos de Metano , Halogênios
12.
J Nat Prod ; 85(6): 1569-1580, 2022 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-35694811

RESUMO

Neuropeptides are a group of neuronal signaling molecules that regulate physiological and behavioral processes in animals. Here, we used in silico mining to predict the polypeptide composition of available transcriptomic data of Turbinaria peltata. In total, 118 transcripts encoding putative peptide precursors were discovered. One neuropeptide Y/F-like peptide, named TpNPY, was identified and selected for in silico structural, in silico binding, and pharmacological studies. In our study, the anti-inflammation effect of TpNPY was evaluated using an LPS-stimulated C8-D1A astrocyte cell model. Our results demonstrated that TpNPY, at 0.75-3 µM, inhibited LPS-induced NO production and reduced the expression of iNOS in a dose-dependent manner. Furthermore, TpNPY reduced the secretion of proinflammatory cytokines. Additionally, treatment with TpNPY reduced LPS-mediated elevation of ROS production and the intracellular calcium concentration. Further investigation revealed that TpNPY downregulated the IKK/IκB/NF-κB signaling pathway and inhibited expression of the NLRP3 inflammasome. Through molecular docking and using an NPY receptor antagonist, TpNPY was shown to have the ability to interact with the NPY Y1 receptor. On the basis of these findings, we concluded that TpNPY might prevent LPS-induced injury in astrocytes through activation of the NPY-Y1R.


Assuntos
Neuropeptídeo Y , Neuropeptídeos , Animais , Astrócitos , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Simulação de Acoplamento Molecular , Neuropeptídeo Y/química , Neuropeptídeo Y/farmacologia , Transcriptoma
13.
Int J Mol Sci ; 23(3)2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-35163801

RESUMO

Transgenic mouse models of Alzheimer's disease (AD) overexpress mutations of the human amyloid protein precursor (APP) and presenilin-1 (PSEN1) genes, which are known causes of amyloid pathology in familial AD. However, animal models for studying AD in the context of aging and age-related co-morbidities, such as blood-brain barrier (BBB) disruptions, are lacking. More recently, aged and progeroid mouse models have been proposed as alternatives to study aging-related AD, but the toxicity of murine amyloid-beta protein (Aß) is not well defined. In this study, we aimed to study the potential toxicity of murine Aß on brain endothelial cells and astrocytes, which are important components of the BBB, using mouse brain endothelial cells (bEnd.3) and astrocytes (C8-D1A). Murine-soluble Aß (1-42) oligomers (sAßO42) (10 µM) induced negligible injuries in an endothelial monolayer but induced significant barrier disruptions in a bEnd.3 and C8-D1A co-culture. Similar results of endothelial perturbation were observed in a bEnd.3 monolayer treated with astrocyte-conditioned medium (ACM) generated by astrocytes exposed to sAßO42 (ACM-sAßO42), while additional exogenous sAßO42 did not cause further damage. Western blot analysis showed that ACM-sAßO42 altered the basal activities of vascular endothelial growth factor receptor 2 (VEGFR2), eNOS, and the signaling of the MEK/ERK and Akt pathways in bEnd.3. Our results showed that murine sAßO42 was moderately toxic to an endothelial and astrocyte co-culture. These damaging effects on the endothelial barrier were induced by deleterious soluble factors released from astrocytes, which disrupted endothelial VEGFR2 signaling and perturbed cell survival and barrier stabilization.


Assuntos
Peptídeos beta-Amiloides/toxicidade , Astrócitos/citologia , Barreira Hematoencefálica/citologia , Óxido Nítrico Sintase Tipo III/metabolismo , Fragmentos de Peptídeos/toxicidade , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Linhagem Celular , Técnicas de Cocultura , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Modelos Biológicos
14.
Int J Mol Sci ; 23(20)2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36293179

RESUMO

Survival and adaptation to seasonal changes are challenging for insects. Many temperate insects such as the rice stem borer (Chilo suppressalis) overcome the adverse situation by entering diapause, wherein development changes dynamically occur and metabolic activity is suppressed. The photoperiod and temperature act as major environmental stimuli of diapause. However, the physiological and molecular mechanisms that interpret the ecologically relevant environmental cues in ontogenetic development during diapause termination are poorly understood. Here, we used genome-wide high-throughput RNA-sequencing to examine the patterns of gene expression during diapause termination in C. suppressalis. Major shifts in biological processes and pathways including metabolism, environmental information transmission, and endocrine signalling were observed across diapause termination based on over-representation analysis, short time-series expression miner, and gene set enrichment analysis. Many new pathways were identified in diapause termination including circadian rhythm, MAPK signalling, Wnt signalling, and Ras signalling, together with previously reported pathways including ecdysteroid, juvenile hormone, and insulin/insulin-like signalling. Our results show that convergent biological processes and molecular pathways of diapause termination were shared across different insect species and provided a comprehensive roadmap to better understand diapause termination in C. suppressalis.


Assuntos
Diapausa , Insulinas , Mariposas , Animais , Fotoperíodo , Transcriptoma , Ecdisteroides , Temperatura , Mariposas/genética , Diapausa/genética , Insetos/genética , Hormônios Juvenis , RNA , Insulinas/genética
16.
Glob Chang Biol ; 25(8): 2530-2543, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30955227

RESUMO

Cover crops play an increasingly important role in improving soil quality, reducing agricultural inputs and improving environmental sustainability. The main objectives of this critical global review and systematic analysis were to assess cover crop practices in the context of their impacts on nitrogen leaching, net greenhouse gas balances (NGHGB) and crop productivity. Only studies that investigated the impacts of cover crops and measured one or a combination of nitrogen leaching, soil organic carbon (SOC), nitrous oxide (N2 O), grain yield and nitrogen in grain of primary crop, and had a control treatment were included in the analysis. Long-term studies were uncommon, with most data coming from studies lasting 2-3 years. The literature search resulted in 106 studies carried out at 372 sites and covering different countries, climatic zones and management. Our analysis demonstrates that cover crops significantly (p < 0.001) decreased N leaching and significantly (p < 0.001) increased SOC sequestration without having significant (p > 0.05) effects on direct N2 O emissions. Cover crops could mitigate the NGHGB by 2.06 ± 2.10 Mg CO2 -eq ha-1  year-1 . One of the potential disadvantages of cover crops identified was the reduction in grain yield of the primary crop by ≈4%, compared to the control treatment. This drawback could be avoided by selecting mixed cover crops with a range of legumes and non-legumes, which increased the yield by ≈13%. These advantages of cover crops justify their widespread adoption. However, management practices in relation to cover crops will need to be adapted to specific soil, management and regional climatic conditions.


Assuntos
Gases de Efeito Estufa , Agricultura , Produção Agrícola , Produtos Agrícolas , Nitrogênio , Solo
17.
Environ Sci Technol ; 53(17): 10246-10257, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31362503

RESUMO

Updating and refining the N2O emission factors (N2O-EFs) are vital to reduce the uncertainty in estimates of direct N2O emissions. Based on a database with 1151 field measurements across China, the N2O-EFs were established via three approaches including the maximum likelihood method, a linear regression with an intercept and a linear regression with the intercept set to 0 using 70% of the observations. The remaining 30% of the observations were then used to evaluate the predicted N2O-EFs. The third method had the highest R2 of 0.39 and the best model efficiency of 0.38 with no significant bias, showing the best calculation efficiency. The results showed that the N2O-EFs varied with agroregions, crops, and management patterns. The agroregions of Huang-Huai-Hai and Yangtze River had the higher N2O-EFs in maize and wheat seasons than other regions, and the highest N2O-EFs of 0.66-0.92% in the rice season was found in the South and Southwest agroregions. Both fertilizer types and water regimes had the remarkable effects on N2O-EFs. Based on the best estimation by the selected method, direct N2O emissions from China's crop cultivation were estimated to be 194 Gg N2O-N with a 95% confidence interval of 180-208 Gg N2O-N in the year 2016.


Assuntos
Poluentes Atmosféricos , Óxido Nitroso , Agricultura , China , Fertilizantes , Nitrogênio , Estações do Ano , Solo
18.
Biochem Biophys Res Commun ; 495(1): 693-699, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29117537

RESUMO

Hypoglycemia is a major barrier to achieving stable metabolic control in patients with diabetes which is a serious clinical concern. With progression of diabetes, the ability of pancreatic α-cells which respond to hypoglycemia becomes impaired; However, it is not clear whether the dysfunctional responses of α-cells during hypoglycemia are related with oxidative stress. In the present study, we investigated whether epigallocatechin-3-gallate (EGCG) has antioxidant potential on pancreatic alpha TC1-6 (αTC1-6) cell lines and protect the normal function of α-cells from H2O2 induced oxidative stress. ROS production, cell viability, glucagon secretion, and cell apoptosis were assessed. EGCG reduced ROS production and cell apoptosis, while restored cell viability and glucagon secretion within a particular concentration range. Moreover, EGCG activated Akt signaling and inhibited P38 as well as JNK mitogen-activated protein kinase (MAPK) pathway. Taken together, EGCG prevented αTC1-6 cells from H2O2 induced oxidative stress, restored dysfunction of glucagon secretion and inhibited cell apoptosis via the activation of Akt signaling and suppression of P38 and JNK pathway. These results provide rationale for combining the conventional anti-hyperglycemia therapy and antioxidant therapy in order to avert hypoglycemia in clinical treatment of diabetes.


Assuntos
Antioxidantes/administração & dosagem , Catequina/análogos & derivados , Células Secretoras de Glucagon/efeitos dos fármacos , Células Secretoras de Glucagon/metabolismo , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Catequina/administração & dosagem , Linhagem Celular , Relação Dose-Resposta a Droga , Peróxido de Hidrogênio/administração & dosagem , Camundongos , Estresse Oxidativo/efeitos dos fármacos
19.
Health Qual Life Outcomes ; 15(1): 145, 2017 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-28716084

RESUMO

BACKGROUND: To develop the Chinese version of quality of life scale for dry eye patients based on the Impact of Dry Eye on Everyday Life (IDEEL) questionnaire and to assess the reliability and validity of the developed scale. METHODS: The original IDEEL was adapted cross-culturally to Chinese language and further developed following standard procedures. A total of 100 Chinese patients diagnosed with dry eye syndrome were included to investigate the psychometric properties of the Chinese version of scale. Psychometric tests included internal consistency (Cronbach's ɑ coefficients), construct validity (exploratory factor analysis), and known-groups validity (the analysis of variance). RESULTS: The Chinese version of Dry Eye Related Quality of Life (CDERQOL) Scale contains 45 items classified into 5 domains. Good to excellent internal consistency reliability was demonstrated for all 5 domains (Cronbach's ɑ coefficients range from 0.716 to 0.913). Construct validity assessment indicated a consistent factorial structure of the CDERQOL scale with hypothesized construct, with the exception of "Dry Eye Symptom-Bother" domain. All domain scores were detected with significant difference across three severity groups of dry eye patients (P < 0.05) except for "Satisfaction with Treatment" domain, indicating good known-groups validity. CONCLUSIONS: The results indicated that the CDERQOL scale is a reliable and valid instrument for patients with dry eye syndrome among Chinese population, and could be used as a supplementary diagnostic and treatment-effectiveness measure.


Assuntos
Síndromes do Olho Seco/psicologia , Qualidade de Vida , Adulto , Idoso , China , Síndromes do Olho Seco/classificação , Análise Fatorial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psicometria , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Inquéritos e Questionários , Traduções
20.
ACS Appl Mater Interfaces ; 16(19): 25415-25421, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38696539

RESUMO

It is of practical significance to develop polymer-based room-temperature phosphorescence (RTP) materials with ultralong lifetime and multicolor afterglow. Herein, the benzocarbazole derivatives were selected and combined with a poly(vinyl alcohol) (PVA) matrix by a coassembly strategy. Owing to the hydrogen-bonding interactions between benzocarbazole derivatives and the PVA matrix, the nonradiative transition and the quenching of triplet excitons are effectively inhibited. Therefore, the maximum phosphorescence emission lifetime of 2202.17 ms from ABfCz-PVA and the maximum phosphorescence quantum efficiency of 34.97% from ABtCz-PVA were obtained, respectively. In addition, commercially available dye molecules were selected to construct phosphorescent resonance energy transfer (PRET) systems for energy acceptors, enabling full-color afterglow emission in blue, green, yellow, red, and even white. Based on the characteristics of prepared RTP materials, multifunctional applications to flexibility, information encryption, and erasable drawing were deeply explored.

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