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1.
PLoS Med ; 21(5): e1004404, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38728366

RESUMO

BACKGROUND: Cholera outbreaks are on the rise globally, with conflict-affected settings particularly at risk. Case-area targeted interventions (CATIs), a strategy whereby teams provide a package of interventions to case and neighboring households within a predefined "ring," are increasingly employed in cholera responses. However, evidence on their ability to attenuate incidence is limited. METHODS AND FINDINGS: We conducted a prospective observational cohort study in 3 conflict-affected states in Nigeria in 2021. Enumerators within rapid response teams observed CATI implementation during a cholera outbreak and collected data on household demographics; existing water, sanitation, and hygiene (WASH) infrastructure; and CATI interventions. Descriptive statistics showed that CATIs were delivered to 46,864 case and neighbor households, with 80.0% of cases and 33.5% of neighbors receiving all intended supplies and activities, in a context with operational challenges of population density, supply stock outs, and security constraints. We then applied prospective Poisson space-time scan statistics (STSS) across 3 models for each state: (1) an unadjusted model with case and population data; (2) an environmentally adjusted model adjusting for distance to cholera treatment centers and existing WASH infrastructure (improved water source, improved latrine, and handwashing station); and (3) a fully adjusted model adjusting for environmental and CATI variables (supply of Aquatabs and soap, hygiene promotion, bedding and latrine disinfection activities, ring coverage, and response timeliness). We ran the STSS each day of our study period to evaluate the space-time dynamics of the cholera outbreaks. Compared to the unadjusted model, significant cholera clustering was attenuated in the environmentally adjusted model (from 572 to 18 clusters) but there was still risk of cholera transmission. Two states still yielded significant clusters (range 8-10 total clusters, relative risk of 2.2-5.5, 16.6-19.9 day duration, including 11.1-56.8 cholera cases). Cholera clustering was completely attenuated in the fully adjusted model, with no significant anomalous clusters across time and space. Associated measures including quantity, relative risk, significance, likelihood of recurrence, size, and duration of clusters reinforced the results. Key limitations include selection bias, remote data monitoring, and the lack of a control group. CONCLUSIONS: CATIs were associated with significant reductions in cholera clustering in Northeast Nigeria despite operational challenges. Our results provide a strong justification for rapid implementation and scale-up CATIs in cholera-response, particularly in conflict settings where WASH access is often limited.


Assuntos
Cólera , Saneamento , Humanos , Nigéria/epidemiologia , Cólera/epidemiologia , Cólera/prevenção & controle , Estudos Prospectivos , Masculino , Higiene , Feminino , Adulto , Epidemias/prevenção & controle , Incidência , Surtos de Doenças/prevenção & controle , Adolescente , Adulto Jovem , Pessoa de Meia-Idade , Criança
2.
Curr Issues Mol Biol ; 44(10): 4859-4876, 2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36286045

RESUMO

The resistance prevalence of chemical fungicides has caused increasingly serious agro-ecological environmental problems. However, there are few previous reports about resistance to succinate dehydrogenase (SDHI) or sterol demethylation inhibitor (DMI) in Rhizoctonia solani, one of the main agro-diseases. In this study, the fungicide resistance of 122 R. solani isolates in Sichuan Province was monitored by the mycelial growth rate method. Results showed that all isolates were susceptible to hexaconazole and most isolates were susceptible to thifluzamide, except for the field isolate MSRS-2-7 due to a moderate resistance to thifluzamide (16.43-fold resistance ratio, RR), compared to the sensitivity baseline of thifluzamide (0.042 µg/mL EC50 values). On the contrary, many isolates showed moderate or high resistance to tebuconazole (10.59- to 60.78-fold RR), reaching EC50 values of 0.54~3.10 µg/mL, especially for a highly resistant isolate LZHJ-1-8 displaying moderate resistance to epoxiconazole (35.40-fold RR due to a 3.54 µg/mL EC50 value). The fitness determination found that the tebuconazole-resistant isolates showed higher fitness cost with these characteristics, including a lower growth rate, higher relative electric conductivity, an increased ability to tolerate tebuconazole, and high osmotic pressure. Four new mutations of cytochrome P450 sterol 14α-demethylase (CYP51), namely, S94A, N406S, H793R, and L750P, which is the target for DMI fungicides, was found in the tebuconazole-resistant isolates. Furthermore, the lowest binding energy with tebuconazole was also found in the LZHJ-1-8 isolate possessing all the mutations through analyses with Discovery Studio software. Therefore, these new mutation sites of CYP51 may be linked to the resistance against tebuconazole, and its application for controlling R. solani should be restricted in some areas.

3.
Ecotoxicol Environ Saf ; 238: 113575, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35500402

RESUMO

Sogatella furcifera is one of the main agricultural pests in many Asian countries, bringing about enormous injury. A triflumezopyrim-resistant (Tri) strain of S. furcifera was established through continuous screening in laboratory. The determination of synergist and enzyme activity indicated that P450s, especially for the upregulation expression of CYPSF01, played a key role in the increased resistance, confirmed by RNAi, and the recombinant protein of CYPSF01 and NADPH-P450 reductase was able to degrade triflumezopyrim. CYPSF01 had an obviously co-expression relationship with nuclear receptor ultraspiracle (USP), which were all significantly up-regulated when exposed to triflumezopyrim. Further, a USP-binding motif MA0534.1 was enriched from the upregulated peaks by Assay for Transposase Accessible Chromatin (ATAC-seq) analysis, which exited in the peaks located on the promoter of CYPSF01; the yeast one-hybrid experiments confirmed that USP could bind to the CYPSF01 promoter. And the USP interference significantly down-regulated CYPSF01 expression, and resulted in the significantly increasing sensitivity to triflumezopyrim, its mortality rate increased 28.37%. Therefore, the overexpression of USP could cause to the overexpression of CYPSF01, ultimately resulting in the resistance to triflumezopyrim in S. furcifera.


Assuntos
Hemípteros , Inseticidas , Animais , Hemípteros/metabolismo , Inseticidas/metabolismo , Piridinas/metabolismo , Pirimidinonas , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo
4.
Int J Mol Sci ; 23(22)2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36430247

RESUMO

Long-term pesticide-driven selection pressure is one of the main causes of insect outbreaks. In this study, we found that low doses of triflumezopyrim could increase the fecundity of white-backed planthoppers (Sogatella furcifera). By continuously screening 20 generations with a low dose of triflumezopyrim, a triflumezopyrim-resistant strain (Tri-strain, resistance ratio = 20.9-fold) was obtained. The average oviposition quantity and longevity of the Tri-strain (208.77 eggs and 21.31 days, respectively) were significantly higher than those of the susceptible strain (Sus-strain) (164.62 eggs and 17.85 days, respectively). To better understand the mechanism underlying the effects on reproduction, we detected the expression levels of several reproduction-related transcription factors in both the Tri- and Sus-strains. Ultraspiracle (USP) was significantly overexpressed in the Tri-strain. Knockdown of USP by RNAi severely inhibited the moulting process of S. furcifera and disrupted the development of female adult ovaries. Among the potential downstream target genes of USP, Kr-h1 (0.19-fold), Cht8 (0.56-fold) and GPCR A22 (0.31-fold) showed downregulated expression after USP-RNAi. In contrast, the expression of EcR (2.55-fold), which forms heterodimers with USP, was significantly upregulated. Furthermore, RNAi was performed on Kr-h1 in the Tri-strain, and the results show that larval moulting and the development of female adult ovaries were inhibited, consistent with the USP-RNAi results in S. furcifera. These results suggest that the transcription factors USP and Kr-h1 play important roles in the reproductive development of S. furcifera, and overexpression of USP and Kr-h1 in the Tri-resistant strain may result in reproductive outbreaks of pests.


Assuntos
Hemípteros , Reprodução , Feminino , Animais , Receptores Citoplasmáticos e Nucleares , Surtos de Doenças , Fatores de Transcrição/genética
5.
J Environ Manage ; 298: 113454, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34365187

RESUMO

The catalytic activity and stability of MnOx/TiO2 and MnOx-CeO2/TiO2 catalysts for the oxidative degradation of 1,2-dichorobenzene (o-DCBz) at low temperatures (≤275 °C) were experimentally examined. The chlorine (Cl) poisoning mechanism of the catalysts was also clarified based on the catalyst characterization combined with theoretical calculations. Experimental results show that the MnOx/TiO2 catalyst is considerably deactivated during o-DCBz catalytic decomposition, mainly due to the chlorination of the catalytic active component. Ce addition and high temperature can effectively promote the resistance of MnOx/TiO2 catalyst to Cl poisoning. Density functional theory (DFT) calculations in the framework of first-principles reveal that Cl atom prefers to anchor on surface oxygen vacancy (OV) rather than on top site of Mn atom. The adsorption of Cl atom on surface OV hinders the dissociated adsorption of O2 on surface OV and interrupts the regeneration of the surface reactive oxygen species. The adsorption of Cl atom on top site of Mn atom increases the formation energy of surface OV and damages the surface Lewis acid sites which act as the important adsorption sites for o-DCBz molecules. Ce addition causes Cl atom to adsorb preferentially onto the OV around Ce atom, which weakens the interaction between Cl atom and Mn atom. Consequently, the chlorination of the MnOx species is prevented and the oxygen mobility of the catalyst is guaranteed to some extent.


Assuntos
Cloro , Titânio , Catálise , Oxirredução
6.
Phytochem Anal ; 31(6): 846-860, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32573880

RESUMO

INTRODUCTION: Caragana jubata Poir (CJ) and Caragana changduensis Liou f. (CC) are the two main original plants of Lignum Caraganae (LIC, a clinically effective Tibetan materia medica) and the red heartwoods of CJ and CC have been used for the treatment of polycythemia, hypertension and menstrual disorders. OBJECTIVE: To establish a comprehensive method for rapid quality assessment of LIC based on revealing the characteristic components of LIC and to discriminate the plant sources and LIC from its adulterations. METHODOLOGY: A multi-index and synthetically balanced orthogonal design L9 (34 ) experiment was performed to obtain an efficient ultrasonic extraction condition of LIC sample. High-performance liquid chromatography coupled with an ultraviolet detector (HPLC-UV) techniques were developed for fingerprinting and quantitative analysis of 14 major compounds in LIC, and the main components were identified by HPLC tandem mass spectrometry (HPLC-MS/MS). HPLC fingerprint and chemometrics analysis were employed to visualise the distinction and relationship of LIC obtained from CJ and CC and to determine their potential characteristic markers. RESULTS: Fourteen compounds including a new compound were identified and quantified in LIC. The potential characteristic markers in LIC were identified based on qualitative and fingerprint analysis. The hierarchical cluster analysis (HCA) and principle component analysis (PCA) showed obvious discrimination between LIC obtained from CJ and CC. Five batches of LIC samples were authenticated, and its adulterations were successfully found. CONCLUSION: A facile HPLC combined with fingerprint and chemometrics methods could rapidly evaluate the quality of LIC and discriminate LIC obtained from CJ and CC.


Assuntos
Caragana , Medicamentos de Ervas Chinesas , Cromatografia Líquida de Alta Pressão , Análise por Conglomerados , Análise de Componente Principal , Espectrometria de Massas em Tandem
7.
J Nat Prod ; 82(10): 2761-2767, 2019 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-31577434

RESUMO

Two new chalcone-isoflavone dimers, caraganins A (1) and B (2), two new chalcone dimers, caraganins C (3) and D (4), and eight known compounds (5-12) were obtained from the red heartwood of the rhizomes of Caragana jubata. The structures of caraganins A-D were established by 1D and 2D NMR spectroscopy, HRMS and ECD analysis, and comparison with previously known compounds. The anti-inflammatory activities of the new compounds were evaluated by measuring the production of NO, IL-6, and TNF-α in mouse RAW 264.7 macrophages induced by lipopolysaccharide. Among these, compounds 2 and 4 showed the most potent inhibitory activities (IC50: 4.1 and 5.2 µM, respectively) on nitric oxide formation, and compounds 1 and 4 displayed the most potent inhibitory activities on the secretion of inflammatory factor TNF-α, with IC50 values of 11.4 and 14.7 µM. The possible biosynthetic pathways of the chalcone-isoflavone dimers and the chalcone dimers are proposed.


Assuntos
Anti-Inflamatórios/isolamento & purificação , Caragana/química , Chalconas/isolamento & purificação , Isoflavonas/isolamento & purificação , Animais , Chalconas/biossíntese , Chalconas/química , Chalconas/farmacologia , Dimerização , Isoflavonas/biossíntese , Isoflavonas/química , Isoflavonas/farmacologia , Camundongos , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Células RAW 264.7 , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/biossíntese
8.
Cell Physiol Biochem ; 36(1): 315-24, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25967970

RESUMO

BACKGROUND/AIMS: It is well documented that hyperglycemia-induced oxidative stress is an important causative factor of endothelial dysfunction. Cinnamaldehyde (CA) is a key flavor compound in cinnamon essential oil that can enhance the antioxidant defense against reactive oxygen species (ROS) by activating NF-E2-related factor 2 (Nrf2), which has been shown to have a cardiovascular protective effect, but its role in endothelial dysfunction induced by high glucose is unknown. METHODS: Dissected male C57BL/6J mouse aortic rings and HUVECs were cultured in normal glucose(NG 5.5 mM) or high glucose(HG 30.0 mM) DMEM treatment with or without CA (10 µM). RESULTS: Treatment with CA protected the endothelium relaxation, inhibited ROS generation and preserved nitric oxide (NO) levels in the endothelium of mouse aortas treated with high glucose . CA up-regulated Nrf2 expression, promoted its translocation to the nucleus'and increased HO-1, NQO1, Catalase and Gpx1 expression under high glucose condition. The increased level of nitrotyrosine in HUVECs under high glucose was also attenuated by treatment with CA. Dihydroethidium (DHE) and DAF-2DA staining indicated that CA inhibited the ROS generation and preserved the NO levels in HUVECs, but these effects were reversed by Nrf2-siRNA in high glucose conditions. CONCLUSION: Our results indicated that CA protected endothelial dysfunction under high glucose conditions and this effect was mediated by Nrf2 activation and the up-regulation of downstream target proteins. CA administration may represent a promising intervention in diabetic patients who are at risk for vascular complications.


Assuntos
Acroleína/análogos & derivados , Antioxidantes/farmacologia , Aorta/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Glucose/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Acroleína/farmacologia , Animais , Aorta/citologia , Células Cultivadas , Endotélio Vascular/citologia , Regulação da Expressão Gênica/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
9.
Cytokine ; 71(1): 60-5, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25226445

RESUMO

This study was designed to investigate whether lacidipine elicited a protective role on cardiomyocyte against apoptosis induced by TNF-α. Neonatal rat cardiomyocytes were randomly assigned into different groups. TUNEL staining was utilized to detect apoptosis, and caspase-3 and caspse-12 were determined. To explore the underlying mechanism, Z-ATAD-FMK (a selective caspase-12 inhibitor) was used to identify the key molecule involved. TNF-α increased caspase-3 expression, which was mediated by increased caspase-12 expression. In the meantime, apoptosis was significantly induced by TNF-α. Lacidipine lowered caspase-12 and caspase-3 expression, and cardiomyocyte apoptosis induced by TNF-α. The results suggest that lacidipine attenuates TNF-α -induced apoptosis via inhibition of caspase-12 and caspase-3 successively.


Assuntos
Apoptose/efeitos dos fármacos , Bloqueadores dos Canais de Cálcio/farmacologia , Di-Hidropiridinas/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia , Animais , Caspase 12/genética , Caspase 12/metabolismo , Caspase 3/genética , Caspase 3/metabolismo , Células Cultivadas , Marcação In Situ das Extremidades Cortadas , Masculino , Miócitos Cardíacos/fisiologia , Distribuição Aleatória , Ratos Sprague-Dawley
10.
Cell Physiol Biochem ; 34(2): 288-98, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25034045

RESUMO

BACKGROUND/AIMS: Obesity contributes to the development of cardiometabolic disorders such as type 2 diabetes, fatty liver disease and cardiovascular disease. Salvianolic acid B (Sal B) is a molecule derived from the root of Salvia miltiorrhiza (Danshen), which is a traditional Chinese medicine that is widely used to treat cardiovascular diseases. However, the role of Sal B in obesity and obesity-related metabolic disorders is unknown. In this study, we aimed to investigate the effects of Sal B on high-fat diet-induced obesity and determine the possible mechanisms involved. METHODS: Male C57BL/6J mice fed a high-fat diet for 12 weeks received a supplement of Sal B (100 mg/kg/day) by gavage for a further 8 weeks. These mice were compared to control mice fed an un-supplemented high-fat diet. 3T3-L1 preadipocytes were used in vitro studies. RESULTS: Sal B administration significantly decreased body weight, white adipose tissue weight, adipocyte size and lipid (triglyceride and total cholesterol) levels in obese mice. Eight weeks of Sal B administration also improved the intraperitoneal glucose tolerance test (IPGTT) and intraperitoneal insulin tolerance test (IPITT) scores in high-fat diet-induced obese mice. In 3T3-L1 preadipocytes that were cultured in vitro and induced to differentiate, Sal B reduced the accumulation of lipid droplets and lipid content in a dose-dependent manner. Immunoblotting indicated that Sal B decreased peroxisome proliferator-activated receptor gamma (PPARγ) and CCAAT/enhancer binding protein α (C/EBPα) expression but increased the expression of GATA binding protein 2 and 3 (GATA 2, GATA 3) both in vivo and in vitro. CONCLUSION: Our data suggest that Sal B may reduce obesity and obesity-related metabolic disorders by suppressing adipogenesis. The effects of Sal B in adipose tissue may be related to its action on PPARγ, C/EBPα, GATA-2 and GATA-3.


Assuntos
Benzofuranos/farmacologia , Dieta Hiperlipídica , Obesidade/fisiopatologia , PPAR gama/metabolismo , Aumento de Peso/efeitos dos fármacos , Células 3T3-L1 , Animais , Hiperlipidemias/prevenção & controle , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/etiologia
11.
J Cardiovasc Pharmacol ; 64(6): 497-506, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25490415

RESUMO

Increasing amounts of evidence implicate oxidative stress as having a pivotal role in age-related cerebrovascular dysfunction, which is an important risk factor for the development of cerebrovascular disease. Previous studies have shown that the activation of the expression of peroxisome proliferator-activated receptor gamma (PPAR-γ) in vascular endothelial cells results in an improvement of vascular function. Pioglitazone, a well-known PPAR-γ agonist, protects against oxidative stress in the rostral ventrolateral medulla by the upregulation of mitochondrial uncoupling protein 2 (UCP2). In this study, we sought to explore the effects and the underlying mechanisms of pioglitazone on age-related oxidative stress elevation and cerebrovascular dysfunction in aging rat cerebral arteries. A natural aging model was constructed and used in these experiments. One-month oral administration of pioglitazone (20 mg·kg·d) ameliorated the production of reactive oxygen species, promoted endothelial nitric oxide synthase phosphorylation and increased the nitric oxide available, thus improving endothelium-dependent relaxation in aging rat cerebral arteries. One-month pioglitazone administration also restored PPAR-γ expression and increased the levels of UCP2 in aging rat cerebral arteries. Using in vitro studies, we demonstrated that pioglitazone attenuated reactive oxygen species levels in aging human umbilical vein endothelial cells through PPAR-γ activation. Furthermore, we found that this occurs in an UCP2-dependent manner. Our study demonstrated that the activation of PPAR-γ by pioglitazone protected against oxidative stress damage in aging cerebral arteries by upregulating UCP2. PPAR-γ may be a new target in treating age-related cerebrovascular dysfunction.


Assuntos
Artérias Cerebrais/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , PPAR gama/agonistas , Tiazolidinedionas/farmacologia , Envelhecimento , Animais , Artérias Cerebrais/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Canais Iônicos/genética , Masculino , Proteínas Mitocondriais/genética , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , PPAR gama/metabolismo , Fosforilação/efeitos dos fármacos , Pioglitazona , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Proteína Desacopladora 2 , Regulação para Cima/efeitos dos fármacos
12.
Psychol Res Behav Manag ; 17: 1935-1945, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38737672

RESUMO

Purpose: The continuous spread of the epidemic has inflicted serious harm upon individual's mental well-being, and effective coping mechanisms are associated with positive mental health outcomes. Prosocial behavior and a sense of meaning in life can enhance individuals' subjective well-being, which can subsequently positively impact their mental health. Thus, in the context of epidemic prevention and control, this study investigates the relationship between the meaning in life, prosocial behavior, and coping styles of outstanding physical education students and the impact on their mental health. Methods: The study involved a questionnaire survey on 498 outstanding physical education students, consisting of 297 boys (mean age = 13.16) and 201 girls (mean age = 12.87 years). Subsequently, the data was analyzed using the mediating effect and Bootstrap tests. Results: The coping style positively predicted the meaning in life (ß=0.294) and prosocial behavior (ß=0.293). Conversely, mental health was predicted in a negative direction (ß=-0.494). Mental health negatively predicted prosocial behavior (ß=-0.810), although prosocial behavior positively predicted meaning in life (ß=0.644). Finally, prosocial behavior negatively predicted mental health (ß=-0.513). Additionally, the interplay between prosocial behavior and meaning in life is established in terms of both the individual and chain mediating roles. Conclusion: This study demonstrates that coping styles during a normalized epidemic prevention and control situation directly impact the mental health of Shanghai's outstanding physical education students. Additionally, these coping styles indirectly influence mental health through the mediating effects of meaning in life and prosocial behaviors. Furthermore, meaning in life and prosocial behaviors act as chain mediators in this relationship.

13.
Sci Total Environ ; 921: 170911, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38354796

RESUMO

Elucidation of the catalytic decomposition mechanism of dioxins is pivotal in developing highly efficient dioxin degradation catalysts. In order to accurately simulate the whole molecular structure of dioxins, two model compounds, o-dichlorobenzene (o-DCB) and furan, were employed to represent the chlorinated benzene ring and oxygenated central ring within a dioxin molecule, respectively. Experiments and Density Functional Theory (DFT) calculations were combined to investigate the adsorption as well as oxidation of o-DCB and furan over MnOx-CeO2/TiO2 catalyst (denoted as MnCe/Ti). The results indicate that competitive adsorption exists between furan and o-DCB. The former exhibits superior adsorption capacity on MnCe/Ti catalyst at 100 °C - 150 °C, for it can adsorb on both surface metal atom and surface oxygen vacancies (Ov) via its O-terminal; while the latter adsorbs primarily by anchoring its Cl atom to surface Ov. Regarding oxidation, furan can be completely oxidized at 150 °C - 300 °C with a high CO2 selectivity (above 80 %). However, o-DCB cannot be totally oxidized and the resulting intermediates cause the deactivation of catalyst. Interestingly, the pre-adsorption of furan on catalyst surface can facilitate the catalytic oxidation of o-DCB below 200 °C, possibly because the dissociated adsorption of furan may form additional reactive oxygen species on catalyst surface. Therefore, this work provides new insights into the catalytic decomposition mechanism of dioxins as well as the optimization strategies for developing dioxin-degradation catalysts with high efficiency at low temperature.

14.
Neurotoxicology ; 105: 96-110, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39276873

RESUMO

Human brain development is a complex, multi-stage, and sensitive process, especially during the fetal stage. Animal studies over the last two decades have highlighted the potential risks of anesthetics to the developing brain, impacting its structure and function. This has raised concerns regarding the safety of anesthesia during pregnancy and its influence on fetal brain development, garnering significant attention from the anesthesiology community. Although preclinical studies predominantly indicate the neurotoxic effects of prenatal anesthesia, these findings cannot be directly extrapolated to humans due to interspecies variations. Clinical research, constrained by ethical and technical hurdles in accessing human prenatal brain tissues, often yields conflicting results compared to preclinical data. The emergence of brain organoids as a cutting-edge research tool shows promise in modeling human brain development. When integrated with single-cell sequencing, these organoids offer insights into potential neurotoxic mechanisms triggered by prenatal anesthesia. Despite several retrospective and cohort studies exploring the clinical impact of anesthesia on brain development, many findings remain inconclusive. As such, this review synthesizes preclinical and clinical evidence on the effects of prenatal anesthesia on fetal brain development and suggests areas for future research advancement.

15.
Micromachines (Basel) ; 15(8)2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39203627

RESUMO

At present, no consensus has been reached on the generation mechanism of anisotropy in materials fabricated by laser powder bed fusion (LPBF), and most attention has been focused on crystallographic texture. In this paper, an analysis and test were carried out on the hardness, defect distribution, residual stress distribution, and microstructure of WE43 magnesium alloy fabricated by LPBF. The results indicate that LPBF WE43 exhibits obvious anisotropy-the hardness HV of X-Z surface (129.9 HV on average) and that of Y-Z surface (130.7 HV on average) are about 33.5% higher than that of X-Y surface (97.6 HV on average), and the endurable load is smaller in the stacking direction Z compared to the X and Y directions. The factors contributing more to the anisotropy are listed as follows in sequence. Firstly, the defect area of the X-Y projection surface is about 13.2% larger than that of the other two surfaces, so this surface shows greatly reduced mechanical properties due to the exponential relationship between the material strength and the number of defects. Secondly, for laser scanning in each layer/time, the residual stress accumulation in the Z direction is higher than that in the X and Y directions, which may directly reduce the mechanical properties of the material. Finally, more fine grains are distributed in X-Z and Y-Z surfaces when comparing them with those in an X-Y surface, and this fine-grain strengthening mechanism also contributes to the anisotropy. After T5 aging heat treatment (250 °C/16 h), a stronger crystallographic texture is formed in the <0001> direction, with the orientation density index increasing from 10.92 to 21.38, and the anisotropy disappearing. This is mainly caused by the enhancement effect of the texture in the <0001> direction on the mechanical properties in the Z direction cancelling out the weakening effect of the defects in the X-Y surface in the Z direction.

16.
Pharm Biol ; 51(1): 74-83, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23035855

RESUMO

CONTEXT: Dracocephalum moldavica Linn (Labiatae) is one of the ethnomedicinal drugs of Uygur in Xinjiang, China. This herb is mainly used in treating cardiovascular diseases, such as atherosclerosis. However, the mechanism of pharmacological activity of D. moldavica has been poorly studied. OBJECTIVE: To explore the pharmacological mechanism of D. moldavica in treating atherosclerosis by investigating the effects of total flavonoids from the aerial portion of D. moldavica on rat vascular smooth muscle cells (VSMCs). MATERIALS AND METHODS: The proliferation and migration of VSMCs were evaluated via a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay and transwell chamber experiment, respectively. The expression of proliferating cell nuclear antigen (PCNA), nuclear factor κB p65 (NF-κB p65), intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) of VSMCs was determined using immunohistochemistry staining and quantitative real-time PCR (qRT-PCR). RESULTS: Total flavonoids (IC(50) = 145.63 µg/mL) significantly inhibited tumor necrosis factor-α (TNF-α) induced VSMC proliferation at concentrations of 25, 50, and 100 µg/mL. Treatment with 50 and 100 µg/mL of total flavonoids also significantly inhibited TNF-α-induced VSMC migration, whereas 25 µg/mL of total flavonoids did not elicit any significant inhibitory effect. In addition, the effects of total flavonoids on inflammatory molecule expression of cells were tested by immunohistochemistry staining, showing that TNF-α-induced expression of PCNA, NF-κB p65, ICAM-1, and VCAM-1 in VSMCs was dose-dependently suppressed by total flavonoids. Furthermore, qRT-PCR data confirmed the inhibition of mRNA expressions of these inflammatory molecules. DISCUSSION AND CONCLUSION: These data suggest that total flavonoids from D. moldavica exhibit anti-inflammatory activities, which is probably one of the underlying mechanisms of D. moldavica for clinical treatment of atherosclerosis.


Assuntos
Anti-Inflamatórios/farmacologia , Flavonoides/farmacologia , Lamiaceae/química , Músculo Liso Vascular/efeitos dos fármacos , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/isolamento & purificação , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Flavonoides/administração & dosagem , Flavonoides/isolamento & purificação , Regulação da Expressão Gênica/efeitos dos fármacos , Concentração Inibidora 50 , Medicina Tradicional Chinesa , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Componentes Aéreos da Planta , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Fator de Necrose Tumoral alfa/farmacologia
17.
Gels ; 9(5)2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37232967

RESUMO

Chitosan hydrogels have a wide range of applications in tissue engineering scaffolds, mainly due to the advantages of their chemical and physical properties. This review focuses on the application of chitosan hydrogels in tissue engineering scaffolds for vascular regeneration. We have mainly introduced these following aspects: advantages and progress of chitosan hydrogels in vascular regeneration hydrogels and the modification of chitosan hydrogels to improve the application in vascular regeneration. Finally, this paper discusses the prospects of chitosan hydrogels for vascular regeneration.

18.
Front Psychol ; 14: 1096649, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37351438

RESUMO

Objective: In order to promote the development of high-quality professional basketball referees in China, we explored the relationship between their coping styles and mood states during the game and assessed the contributions of psychological resilience and frustration tolerance to this relationship. Methods: A total of 364 national and international male and female basketball referees were recruited and surveyed via the online questionnaire platform "Questionnaire Star". All participants signed an informed consent form and completed the questionnaire. Common method bias test and Pearson correlation tests were used to analyze the study indicators, and the theoretical model for this study was validated using Process plug-in developed by Hayes. Results: The results of the study showed that the coping style of the referees significantly predicted their psychological resilience, frustration tolerance, and mood state. Coping style enhanced psychological resilience (ß = -0.30) and frustration tolerance (ß = 0.38) and improved the mood states (ß = 0.33) of the referees. In addition, coping style directly predicted mood state but also indirectly predict mood state through the intermediary variables of psychological resilience (ß = 0.14) and frustration tolerance (ß = 0.11), and the mediating effects accounted for 24.20 and 18.90% of the total effect, with psychological resilience playing a greater role than frustration tolerance. (ß: standardized regression coefficient). Conclusion: These findings suggest that when training high-level basketball referees, increasing the psychological indicators related to the coping styles and psychological resilience of high-level basketball referees can avoid their large emotional fluctuations and improve their accuracy in judging when facing unexpected events on the court.

19.
Front Psychol ; 14: 1110642, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37077843

RESUMO

Introduction: This study explored the effects of coping style and two potential intermediately factors (cognitive reappraisal and psychological resilience) on the mental health of middle school students during the normalization of epidemic prevention and control in China. Methods: Answers on questionnaires designed to assess coping style, cognitive reappraisal, psychological resilience, and mental health among 743 middle school students (386 boys, 357 girls, 241 first graders, 235 second graders, and 267 third graders) were analyzed using structural equation modeling. Results: The results showed that coping style, cognitive reappraisal, and psychological resilience directly predicted mental health. The negative effect of a negative coping style on mental health was significantly stronger than the positive effect of a positive coping style. Coping style affected mental health through the independent mediating effects of cognitive reappraisal and psychological resilience and through their chain mediation. Discussion: The use of positive coping styles by most students led to greater cognitive reappraisal, strengthened psychological resilience, and thus few mental health problems. These findings provide empirical evidence and may guide educators in the prevention and intervention of mental health problems among middle school students.

20.
Sci Rep ; 13(1): 20622, 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-37996519

RESUMO

As a supplement to large power grids, DC microgrids with new energy access are increasingly widely used. However, with the increasing proportion of new energy in DC microgrids, its output fluctuations directly affect the overall stability of the microgrids. Distributed energy storage can smooth the output fluctuation of distributed new energy. In this paper, an AC-DC hybrid micro-grid operation topology with distributed new energy and distributed energy storage system access is designed, and on this basis, a coordinated control strategy of a micro-grid system based on distributed energy storage is proposed. To maintain the voltage stability of the DC bus and make each station have the power-sharing ability, the AC/DC flexibly interconnected converter should adopt two control strategies. The power can flow bidirectional in the power scheduling and distribution of the energy storage station; At the same time, different power distribution schemes will generate different scheduling costs. To optimize the operation of energy storage power stations, an improved particle swarm optimization algorithm is adopted in this paper to optimize the scheduling task allocation scheme. The optimization objective is the lowest scheduling cost, to realize the optimal scheduling of energy storage power stations. In this paper, based on a Matlab/Simulink environment, a microgrid system based on an AC-DC hybrid bus is built. The simulation results verify the effectiveness of the proposed microgrid coordinated control strategy.

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