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1.
J Environ Manage ; 319: 115696, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35849930

RESUMO

Biopesticides have been recognized as viable alternatives to chemical pesticides in controlling agricultural pests for plants and reducing harmful chemical residues. However, small and marginal farmers are facing challenges while adopting biopesticides, namely, high cost and complicated application techniques, resulting in a low level of farmer acceptance. Accordingly, Farmer Producer Organizations (FPOs), voluntarily formed by farmers, develop mutual technical assistance among their members to solve the technical problems of biopesticide adoption. This study assumes that as a new form of farmer cooperative, FPOs have the potential to promote biopesticide adoption through the implementation of collective pesticide adoption (CPA). Along this line, this paper uses a cooperative game-based hybrid method to develop an incentive mechanism of biopesticide adoption for FPOs to implement CPAs. First, we construct a CPA decision model for mixed pesticides (i.e., biopesticides and chemical pesticides) based on multichoice goal programming (MCGP) to compromise the conflicting objectives regarding cost efficiency and chemical residue reduction, thereby obtaining the optimal total cost of pesticide adoption. Second, recognizing the optimal total adoption cost as a baseline, we devise a cooperative game-based cost allocation scheme to maintain farmers' voluntary participation in FPOs. This study demonstrates that the CPA implemented based on our proposed models can at least match if not surpass the economic and environmental performance of farmers' independent pesticide adoption (IPA). We further demonstrate that the proposed cooperative game solution is more suitable for the FPO's cost allocation issue than the eminent solutions, such as the Shapley value.


Assuntos
Fazendeiros , Praguicidas , Agricultura , Agentes de Controle Biológico , Teoria dos Jogos , Humanos , Motivação
2.
Acta Pharmacol Sin ; 43(11): 2905-2916, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35459869

RESUMO

Anterior gradient 2 (AGR2), a protein disulfide isomerase (PDI), is a multifunctional protein under physiological and pathological conditions. In this study we investigated the roles of AGR2 in regulating cholesterol biogenesis, lipid-lowering efficiency of lovastatin as well as in protection against hypercholesterolemia/statin-induced liver injury. We showed that AGR2 knockout significantly decreased hepatic and serum total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) in mice with whole-body or hepatocyte-specific Agr2-null mutant, compared with the levels in their wild-type littermates fed a normal chow diet (NCD) or high-fat diet (HFD). In contrast, mice with AGR2 overexpression (Agr2/Tg) exhibited an increased cholesterol level. Mechanistic studies revealed that AGR2 affected cholesterol biogenesis via activation of AKT/sterol regulatory element-binding protein-2 (SREBP2), to some extent, in a PDI motif-dependent manner. Moreover, elevated AGR2 led to a significant decrease in the lipid-lowering efficacy of lovastatin (10 mg· kg-1· d-1, ip, for 2 weeks) in mice with hypercholesterolemia (hyperCho), which was validated by results obtained from clinical samples in statin-treated patients. We showed that lovastatin had limited effect on AGR2 expression, but AGR2 was inducible in Agr2/Tg mice fed a HFD. Further investigations demonstrated that drug-induced liver toxicity and inflammatory reactions were alleviated in hypercholesterolemic Agr2/Tg mice, suggesting the dual functions of AGR2 in lipid management and hyperCho/statin-induced liver injury. Importantly, the AGR2-reduced lipid-lowering efficacy of lovastatin was attenuated, at least partially, by co-administration of a sulfhydryl-reactive compound allicin (20 mg· kg-1· d-1, ip, for 2 weeks). These results demonstrate a novel role of AGR2 in cholesterol metabolism, drug resistance and liver protection, suggesting AGR2 as a potential predictor for selection of lipid-lowering drugs in clinic.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Inibidores de Hidroximetilglutaril-CoA Redutases , Hipercolesterolemia , Camundongos , Animais , Lovastatina/farmacologia , Lovastatina/uso terapêutico , Lovastatina/metabolismo , Hipercolesterolemia/tratamento farmacológico , Inibidores de Hidroximetilglutaril-CoA Redutases/metabolismo , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Doença Hepática Crônica Induzida por Substâncias e Drogas/tratamento farmacológico , LDL-Colesterol , Fígado/metabolismo
3.
Artigo em Inglês | MEDLINE | ID: mdl-34948553

RESUMO

With the accelerated iteration of global electronic and electrical product updates, the demand for electronic and electrical products presents a new trend in which the life cycle of electronic and electrical products is shortened. Waste electrical and electronic equipment (WEEE) products pose a great threat to the global ecological environment, and solving this problem is urgent. Therefore, governments around the world have formulated funding policies for WEEE products, which has led to continuous improvements in such policies. Along these lines, we adopt the circular economy concept, extended producer responsibility theory and life cycle assessment method to comparatively analyse and compare the different fund operation modes in China, Germany, Japan and The Netherlands. In addition, based on the data related to fund policy implementation, we point out the problems in the development of the WEEE industry in China. The analysis results show that although China is the largest WEEE market, it is still in the initial stage and lags behind Western countries in efficiency and cost management. Then, taking as an example 'Go Green', an O2O classified recycling platform launched in 2005, this paper performs an extended analysis of the "Internet +" recycling model, which was proposed as a WEEE fund operation solution in China. Finally, we discuss the economic impact of this study on the future implementation and valuation of WEEE fund policy.


Assuntos
Resíduo Eletrônico , Administração Financeira , Gerenciamento de Resíduos , Resíduo Eletrônico/análise , Eletrônica , Políticas , Reciclagem
4.
Exp Ther Med ; 19(4): 2895-2900, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32256774

RESUMO

The present study was designed to investigate the role of nicotinamide phosphoribosyltransferase (Nampt) overexpression in a rat model of Hashimoto's thyroiditis (HT) and its mechanism of action. A rat model of HT was constructed, and the HT rats were injected with an adenoviral expression vector carrying the Nampt gene. The expression of Nampt and Toll-like receptor 4 (TLR4) in thyroid tissues was examined using immunohistochemistry (IHC), RT-qPCR and western blot analyses. Serum anti-thyroglobulin antibodies (TGAb) and anti-thyroid peroxidase antibodies (TPOAb) were measured using chemiluminescence method. Hematoxylin and eosin (H&E) and IHC staining of the rat thyroid tissues showed destroyed thyroid follicles and monocyte infiltration, as well as increased Nampt expression in the thyroid tissues of rats with HT. Furthermore, it was found that Nampt overexpression led to increased severity of inflammatory infiltration in thyroid tissues and increased levels of TPOAb in the serum of HT rats; however, the serum TGAb level was not affected by Nampt overexpression. In addition, Nampt overexpression promoted TLR4 expression in HT rats. In conclusion, it was demonstrated that Nampt was strongly expressed in the capillary region of HT rats thyroid tissues. The Nampt mRNA level was increased but the Nampt protein level was decreased in the thyroid tissues of rats with HT. Nampt overexpression has a promotive effect on HT progression, and this effect was related to TLR4. This study suggests that inhibition of Nampt activity may be valuable in the treatment of HT.

5.
Artigo em Inglês | MEDLINE | ID: mdl-30658429

RESUMO

The evaluation of urban sustainability plays a crucial role in the process of the sustainable development of cities. To decrease subjectivity and attain a comprehensive evaluation, this paper develops an evaluation method using the technique for order preference by similarity to ideal solution (TOPSIS). First, an evaluation index system including 39 indices and three categories (economic, social, and ecological development) is established; second, based on the index system, a modified TOPSIS, in which the entropy method is used to assign weights to each index according to its evaluation score and grey relation analysis is used to reduce the uncertainty existing in the process of evaluation, is presented to rank the sustainability level of cities. Finally, an example with the sustainability evaluation of 16 cities in the Anhui province of China is introduced to verify the effectiveness of the model.


Assuntos
Desenvolvimento Sustentável , China , Cidades/estatística & dados numéricos , Incerteza
6.
Artigo em Inglês | MEDLINE | ID: mdl-29186934

RESUMO

Carbon tax regulation and consumers' low-carbon preference act as incentives for firms to abate emissions. Manufacturers can improve product sustainability and retailers can strengthen the promotion of low-carbon products as part of such abatement. Current incomplete rationality also affects product sustainability and low-carbon promotion level. In this context, we consider a supply chain with a manufacturer and a retailer and investigate the impacts of the manufacturer's and the retailer's fairness concerns on their production sustainability level, low-carbon promotion level and profitability. We also explore the coordination contract. The results show that the manufacturer's and the retailer's fairness concerns decrease their product sustainability and low-carbon promotion level, together with the profits of the system and the manufacturer. With regard to the retailer's fairness concern, the product sustainability level and the manufacturer's profit are lower; moreover, the low-carbon promotion level and the profits of the supply chain and the retailer are higher. A revenue-sharing contract can coordinate the supply chain perfectly; however, members' fairness concerns increase the difficulty of coordination. Finally, the numerical results reveal that carbon tax regulation can encourage the manufacturer to enhance the product sustainability level. Further, the impacts on the low-carbon promotion level and firms' profitability are related to the cost coefficients of product sustainability.


Assuntos
Carbono , Comportamento do Consumidor/economia , Impostos/legislação & jurisprudência , Custos e Análise de Custo , Tomada de Decisões , Modelos Teóricos
7.
Graefes Arch Clin Exp Ophthalmol ; 252(1): 35-42, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23873253

RESUMO

BACKGROUND: In Coats' disease, the most recent development in the treatment has been the intravitreal injection of anti-VEGF agents. The purpose of this article was to evaluate the effect of intravitreal bevacizumab as the initial treatment for Coats' disease in children and adults. METHODS: The study included 14 pediatric patients and five adult patients with Coats' disease. They were treated with intravitreal bevacizumab (1.25 mg/0.05 ml) as the initial treatment, combined with or without other treatments. The analyses included the evaluation of basic clinical conditions. RESULTS: In the pediatric group, after a mean of 9.1 months of follow-up, the differences in visual acuity were significant for the comparisons between the baseline examination and the follow-up examinations carried out at weeks 6, 12, and 24 after the baseline (P = 0.006, P = 0.004, P = 0.005 respectively). Vitreoretinal fibrosis was observed in three patients (n = 3, 21.4 %), among whom two showed fibrosis before treatment. All of the pediatric patients showed a resolution of fluid and exudation, and regression of the telangiectasia. In the adult group, after a mean of 10.6 months of follow-up, the differences in visual acuity were not statistically significant (P > 0.05) between the baseline and follow-up examinations. Vitreoretinal fibrosis (n = 2, 40 %) was observed in two patients who both showed fibrosis before treatment. All of the adult patients showed a resolution of fluid and exudation, and regression of the telangiectasia. The differences in the change of BCVA between children and adults were not significant (P > 0.05) during the follow-up examinations. CONCLUSION: The intravitreal injection of bevacizumab as the initial treatment is associated with a measurable gain in visual acuity in patients with Coats' disease. Resolution of the subretinal fluid and exudation, and regression of the telangiectasia were observed in both pediatric and adult patients. Vitreoretinal fibrosis may be one of the natural courses of Coats' disease, and it remains uncertain whether bevacizumab accelerates the fibrosis phenomenon.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Telangiectasia Retiniana/tratamento farmacológico , Adulto , Bevacizumab , Criança , Pré-Escolar , Feminino , Fibrose , Angiofluoresceinografia , Seguimentos , Humanos , Injeções Intravítreas , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Oftalmoscopia , Retina/patologia , Telangiectasia Retiniana/diagnóstico , Estudos Retrospectivos , Tomografia de Coerência Óptica , Ultrassonografia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Acuidade Visual/fisiologia , Corpo Vítreo/patologia , Adulto Jovem
8.
Mol Vis ; 19: 2227-36, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24227918

RESUMO

PURPOSE: Our previous study showed that apelin was increased in the vitreous and fibrotic membranes of patients with proliferative diabetic retinopathy (PDR) in vivo, which suggested that apelin may be involved in the development of PDR. In this study, we investigated whether the expression of apelin was upregulated in human retinal pigment epithelial (RPE) cells in vitro under high glucose conditions. Furthermore, to explore the role of apelin in RPE cells, we investigated the effect of exogenous recombinant apelin on proliferation, migration, and collagen I (a major component of extracellular matrix molecules, associated with PDR) expression and investigated the signaling pathways involved in these processes. METHODS: Real-time PCR and western blot were performed to determine the apelin expression in ARPE-19 cells under high glucose conditions. Exogenous recombinant apelin was used to study the effect of apelin on ARPE-19 cells in vitro. Cell proliferation, migration, and collagen I expression were assessed using an MTT assay, a transwell assay, and real-time PCR analysis. LY294002 (an inhibitor of phosphatidylinositol 3-kinase) and PD98059 (an inhibitor of mitogen-activated protein kinase) were used to help to determine the apelin signaling mechanism. RESULTS: High glucose upregulated apelin expression in RPE cells. Exogenous recombinant apelin activated protein kinase B (Akt) and extracellular signal-regulated kinase (Erk) phosphorylation and promoted proliferation, migration, and collagen I expression in RPE cells. Pretreatment with LY294002 and PD98059 abolished apelin-induced activation of Akt and Erk, proliferation, and collagen I expression. Apelin-induced migration was partially blocked by pretreatment with LY294002 and PD98059. CONCLUSIONS: The expression of apelin was upregulated under high glucose conditions in RPE cells in vitro. Exogenous recombinant apelin increased the biologic activity of RPE cells, as well as the expression of collagen I. Apelin promoted proliferation, migration, and collagen I expression through the PI3K/Akt and MEK/Erk signaling pathways in RPE cells. From these results, we revealed the role of apelin in regulating proliferation, migration, and collagen I expression in RPE cells and the signaling mechanism under these processes, which suggested that apelin may play a profibrotic role in the development of PDR.


Assuntos
Movimento Celular/efeitos dos fármacos , Colágeno Tipo I/genética , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Epitélio Pigmentado Ocular/citologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Apelina , Proliferação de Células/efeitos dos fármacos , Colágeno Tipo I/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Glucose/farmacologia , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Sistema de Sinalização das MAP Quinases/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Fosforilação/efeitos dos fármacos , Epitélio Pigmentado Ocular/efeitos dos fármacos , Epitélio Pigmentado Ocular/enzimologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
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