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1.
PLoS One ; 16(8): e0254428, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34432816

RESUMO

A scientific measurement of the amount of tradable water rights forms the premise for reaching an agreement in water rights trading. However, the existing measurement methods, based on water saving potential, still have problems caused by large computation workload and difficult-to-control errors. Conflicts also easily emerge between transferor and transferee during the execution of transaction agreements. This paper proposes a new method for measuring tradable water rights from the perspective of an assessment of the risk of water shortage for the transferor. The following describes the basic idea: An index system is established for the assessment of the water shortage risk of the transferor to identify water shortage risk categories. The impact of the water rights transaction volume on the transferor's water shortage risk category is analyzed under different incoming water frequencies. The transferor's water shortage risk threshold is set and a simulated annealing algorithm is designed to calculate the theoretical value of tradable water rights. The following summarizes the innovation of the proposed method: The water resource shortage risk evaluation index of the transferor is constructed based on water resource endowment, water supply, water demand, and water ecological environment of the transferor; then, a risk classification evaluation model of water resource shortage is established and a measurement method of tradable water rights is introduced. Comprehensive analysis of a case analysis of Helan County in the Ningxia Autonomous Region, China, shows that the recommended value of tradable water rights of Helan County is 40 million m3. Various methods are used to calculate the weights of evaluation indexes, which are compared to the measured results of tradable water rights; moreover, the sensitivity of the results is analyzed. The obtained results show that the use of water-saving potential to measure the amount of tradable water rights is feasible.


Assuntos
Meio Ambiente , Modelos Teóricos , Recursos Hídricos , Abastecimento de Água , China
2.
Artigo em Inglês | MEDLINE | ID: mdl-33669014

RESUMO

The formation of the water rights trading price is an important part of the water rights trading system. In order to continuously and dynamically reflect the social-economic development changes and water resource scarcity, herein, we discuss the dynamic adjustment of the water rights trading price from the perspective of water resource scarcity value analysis. First, we constructed the water resource scarcity evaluation index system from the four dimensions of the water resource natural endowment, the water resource supply, the water resource demand, and the water environment, and then we constructed the water resource scarcity index calculation model of the transferor, the transferee, and the comprehensive water resource scarcity index calculation model of both parties of the trading. Second, by analyzing the 30 comparable water rights trading cases in China since 2016, we established the response function of the water rights trading price to the water resource scarcity index, and then we analyzed the impact mechanism of the water resource scarcity index on the water rights trading price. Third, based on the two factors of "the water resource scarcity value" and "the capital time value," we constructed a dynamic price adjustment model of water rights trading for different adjustment factors, so as to adjust the water rights trading price scientifically. Finally, we took the water rights trading in Helan County (Helan) of Ningxia Hui Autonomous Region (Ningxia) as an example. The research shows that: (1) During the trading period of water rights in Helan, the water resource scarcity index rises, and the water rights trading price should be increased year-by-year. Additionally, there are certain differences in the water rights trading price changes with the adjustment of different elements. Among them, considering the adjustment of "the water resource scarcity value" element, the water rights trading price of Helan should be increased from 1.0940 to 2.8574 CNY/m³ during the water rights trading period; (2) there are differences in the water rights trading cost under different payment modes, among which the annual payment mode increased the most, i.e., from 2.7350 × 108 to 7.4500 × 108 CNY. This study suggests exerting a regulating effect of the water scarcity value on the water rights trading price, so as to promote the construction of a more equitable and long-term water rights trading market.


Assuntos
Administração Financeira , Recursos Hídricos , China , Água , Abastecimento de Água
3.
Artigo em Inglês | MEDLINE | ID: mdl-33573251

RESUMO

Ecological compensation is an effective means to solve the conflict of interests among trans-boundary river basin countries. How to determine the ecological compensation standard is the core of ecological compensation. On the basis of the emergy synthesis method, we developed an emergy-water resources ecological footprint model for trans-boundary river basin countries. Based on the calculation of ecosystem service value and consumption ecological value of trans-boundary river basin countries, the ecological spillover value of each basin country is obtained. From the perspective of supply and consumption, the ecological compensation standard in basin countries is determined by judging the supply and consumption status of ecological services and combining with the willingness to pay for ecological compensation. Taking the Lancang-Mekong River Basin as an example, the results show that (1) the ecosystem service value of the Lancang-Mekong River Basin countries from high to low is Laos, Cambodia, Thailand, China, Vietnam, and Myanmar; (2) in terms of ecosystem service value consumption, the order from high to low is Thailand, Cambodia, Vietnam, China, Laos, and Myanmar; and (3) Thailand and Vietnam, located in the lower reaches of the basin, belong to the consumers of ecological services, and based on the actual willingness to pay, they need to pay $46.913 billion and $1.699 billion, respectively.


Assuntos
Ecossistema , Rios , Camboja , China , Laos , Mianmar , Padrões de Referência , Tailândia , Vietnã
4.
Artigo em Inglês | MEDLINE | ID: mdl-33466909

RESUMO

Tradable water volumes is one of the basic elements of water-rights trading. In China, water-rights transactions mostly occur in water-deficient areas. However, the water-rich areas are also facing serious water-shortage problems. It is necessary to stimulate the water-rights trading power in abundant water areas to improve water-resource predicament. This paper studied the concept and calculation method of tradable water volumes of industry. First, based on the property rights theory, we analyzed the concept of tradable water volumes, and put forward the preliminary determination of water-rights trading subjects. Then, we defined the tradable water volumes of industry as the difference between the initial water-rights allocation and the water demand of industry. We used the proportion method to calculate the initial water-rights allocation of industry under different runoff frequencies, and grey model (1,1) to predict the water demand of industry. Finally, we applied the calculation method to Changsha city which is in a water-rich area of China. The calculation results contribute to water-resource management in Changsha city. This paper will provide a theoretical basis for researching the tradable water volumes, and promote the development of water-rights trading in China's water-rich areas.


Assuntos
Indústrias , Água , China , Cidades , Humanos , Recursos Hídricos
5.
Artigo em Inglês | MEDLINE | ID: mdl-33092086

RESUMO

The issue of trans-boundary water conflict has become an important factor affecting the relations between basin countries. The key to solve the current conflict problem is to realize the fair and reasonable allocation of trans-boundary water resources. Based on the satisfaction perspective, we developed an asymmetric Nash negotiation model to obtain an optimal and feasible allocation scheme for the trans-boundary water resources. Firstly, based on the two international water laws, we analyzed the influencing factors including water demand differences, resource endowment differences, and water efficiency differences, and by combing with the flexible weight constraint, we built the fair and reasonable allocation pattern for trans-boundary water resources. Secondly, under the constraint of the allocation pattern, we determined the ideal negotiation scheme of each basin country by considering their selection preference. Thirdly, we built a satisfaction degree function and established an asymmetric Nash negotiation model. This is used to build a fair negotiation mechanism among basin countries, and the allocation scheme after negotiation is regarded as the optimal allocation scheme. Lastly, we took the Lancang-Mekong river basin as an example. For this example, the results indicate the following: (1) after considering multiple factors comprehensively, China and Thailand obtained a higher proportion of trans-boundary water resource quota under different preference scenarios, while Myanmar obtained a lower proportion of trans-boundary water resource quota; (2) taking each basin country as the negotiation agent, the optimal allocation scheme with the introduction of fair negotiation mechanism has a higher degree of satisfaction, with an average of over 87.19%, which is more stable and easy to be accepted by all basin countries; (3) from the perspective of the change rate and the average satisfaction of the basin countries, the optimal allocation scheme under the resource endowment preference scenario obtained the highest satisfaction among basin countries. This study aims to improve the practicability and acceptability of trans-boundary water resources allocation, thus providing technical support for reducing trans-boundary water resources conflicts.


Assuntos
Negociação , Recursos Hídricos , China , Mianmar , Satisfação Pessoal , Alocação de Recursos , Rios , Tailândia
6.
World J Clin Cases ; 8(15): 3372-3376, 2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32874995

RESUMO

BACKGROUND: New direct-acting antivirals (DAAs)-based anti-hepatitis C virus (HCV) therapies are highly effective in patients with HCV infection. However, safety data are lacking regarding HCV treatment with DAAs and drugs for comorbidities. CASE SUMMARY: Herein, we reported a case of HCV-infection in a 46-year-old man with benign prostatic hypertrophy. The patient received sofosbuvir/velpatasvir as well as methadone maintenance therapy for drug abuse. The viral load became negative at week 1 post treatment. He developed facial and bilateral lower extremity edema 48 h after starting receiving tamsulosin. Edema disappeared 10 d after treatment with oral furosemide and spironolactone. CONCLUSION: In conclusion, this is the first case of an acute edema in the course of treatment with new DAAs, methadone and tamsulosin. These agents are useful in clinical management of patients with HCV infection, particularly in men with benign prostatic hypertrophy. Clinicians should be aware of potential drug-drug interactions in this subset of patients.

7.
J Med Virol ; 92(12): 3119-3124, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32470169

RESUMO

Hand, foot, and mouth disease (HFMD) caused by enterovirus 71 (EV71) can lead to high morbidity and mortality, and genetic background plays an important role during the disease process. We investigated the association between the single-nucleotide polymorphism (SNP) rs2564978 of the CD55 gene and susceptibility to and severity of HFMD using the SNPs can multiple SNP typing methods. Soluble CD55 (sCD55) expression was significantly lower in the EV71 HFMD group than in the control group and lower in severe cases than in mild cases (P < .001). Moreover, CD55 rs2564978 (C vs T OR = 1.300, 95% CI, 1.120-1.509) was associated with the risk of EV71 infection, and genotype TC was related to the severity of the infection (TC vs TT OR = 4.523, 95% CI, 2.033-10.066). Our results suggest that sCD55 expression and the CD55 polymorphism rs2564978 may influence the susceptibility to and severity of EV71 infection.

8.
World J Gastroenterol ; 26(13): 1525-1539, 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32308352

RESUMO

BACKGROUND: Nucleos(t)ide analog (NA) has shown limited effectiveness against hepatitis B surface antigen (HBsAg) clearance in chronic hepatitis B (CHB) patients. AIM: To evaluate the efficacy and safety of add-on peginterferon α-2a (peg-IFN α-2a) to an ongoing NA regimen in CHB patients. METHODS: In this observational study, 195 CHB patients with HBsAg ≤ 1500 IU/mL, hepatitis B e antigen (HBeAg)-negative (including HBeAg-negative patients or HBeAg-positive patients who achieved HBeAg-negative after antiviral treatment with NA) and hepatitis B virus-deoxyribonucleic acid < 1.0 × 102 IU/mL after over 1 year of NA therapy were enrolled between November 2015 and December 2018 at the Second Affiliated Hospital of Xi'an Jiaotong University, China. Patients were given the choice between receiving either peg-IFN α-2a add-on therapy to an ongoing NA regimen (add-on group, n = 91) or continuous NA monotherapy (monotherapy group, n = 104) after being informed of the benefits and risks of the peg-IFN α-2a therapy. Total therapy duration of peg-IFN α-2a was 48 wk. All patients were followed-up to week 72 (24 wk after discontinuation of peg-IFN α-2a). The primary endpoint was the proportion of patients with HBsAg clearance at week 72. RESULTS: Demographic and baseline characteristics were comparable between the two groups. Intention-to-treatment analysis showed that the HBsAg clearance rate in the add-on group and monotherapy group was 37.4% (34/91) and 1.9% (2/104) at week 72, respectively. The HBsAg seroconversion rate in the add-on group was 29.7% (27/91) at week 72, and no patient in the monotherapy group achieved HBsAg seroconversion at week 72. The HBsAg clearance and seroconversion rates in the add-on group were significantly higher than in the monotherapy group at week 72 (P < 0.001). Younger patients, lower baseline HBsAg concentration, lower HBsAg concentrations at weeks 12 and 24, greater HBsAg decline from baseline to weeks 12 and 24 and the alanine aminotransferase ≥ 2 × upper limit of normal during the first 12 wk of therapy were strong predictors of HBsAg clearance in patients with peg-IFN α-2a add-on treatment. Regarding the safety of the treatment, 4.4% (4/91) of patients in the add-on group discontinued peg-IFN α-2a due to adverse events. No severe adverse events were noted. CONCLUSION: Peg-IFN α-2a as an add-on therapy augments HBsAg clearance in HBeAg-negative CHB patients with HBsAg ≤ 1500 IU/mL after over 1 year of NA therapy.


Assuntos
Antivirais/administração & dosagem , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/imunologia , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/administração & dosagem , Nucleosídeos/administração & dosagem , Polietilenoglicóis/administração & dosagem , Adulto , China , Quimioterapia Combinada , Feminino , Antígenos de Superfície da Hepatite B/imunologia , Hepatite B Crônica/sangue , Hepatite B Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Proteínas Recombinantes/administração & dosagem , Soroconversão , Resultado do Tratamento
9.
World J Gastroenterol ; 25(44): 6551-6560, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31802834

RESUMO

BACKGROUND: Regimens involving direct-acting antiviral agents (DAAs) are recommended for the treatment of infection with hepatitis C virus (HCV) genotypes 1, 2 and 3. But real-world data is still not enough, especially in Asia. AIM: To investigate the efficacy and safety of DAA-based regimens in a real-life setting in China. METHODS: This study included 366 patients infected with HCV genotypes 1, 2 and 3, with or without cirrhosis, who were observed between May 2015 and December 2018. They were treated with ledipasvir and sofosbuvir (SOF) (genotype 1) with or without ribavirin (RBV), SOF and RBV (genotype 2), or SOF and daclatasvir (genotype 3), with or without RBV, for 12 or more wk. The participants' sustained virological responses (SVR) at post-treatment week 12 (SVR12) was the primary endpoint. The occurrence of adverse events and drug-drug interactions were recorded. RESULTS: In the 366 patients, genotype 1 (59.0%) was the most common genotype, followed by genotypes 2 (34.4%) and 3 (6.6%). Liver cirrhosis was diagnosed in 154 (42.1%) patients. Fifty (13.7%) patients were treatment-experienced. Intention-to-treat analysis revealed that SVR12 was 86.3% (316/366). For modified intention-to-treat analysis, SVR12 was achieved in 96.6% of overall patients (316/327), 96.3% in patients with genotype 1, 97.5% in those with genotype 2, and 95.0% in those with genotype 3. Most of the treatment failures were due to lack of follow-up (3 cases had non-responses, 1 had virological breakthrough, 11 relapsed and 36 did not participate in the follow-up). There was no significant difference in SVR between different genotypes and liver statuses (P < 0.05). Patients with lower alanine aminotransferase levels at baseline who achieved an end of treatment response were more likely to achieve SVR12 (P < 0.05). High SVR was observed regardless of age, gender, liver status, alpha-fetoprotein, HCV RNA levels or history of antiviral therapy (P > 0.05 for all). The cumulative hepatocellular carcinoma occurrence and recurrence rate after using the DAAs was 0.9%. Most of the adverse events were mild. We found two cases of special adverse events. One case involved facial and bilateral lower extremity edema, and the other case showed an interesting change in lipid levels while on medication. No severe adverse events were noted. CONCLUSION: The DAA-based regimens tested in this study have excellent effectiveness and safety in all patients infected with HCV genotypes 1, 2 and 3, including those with cirrhosis.


Assuntos
Antivirais/administração & dosagem , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Cirrose Hepática/tratamento farmacológico , Adulto , Antivirais/efeitos adversos , Antivirais/farmacocinética , China , Interações Medicamentosas , Quimioterapia Combinada/efeitos adversos , Quimioterapia Combinada/métodos , Feminino , Genótipo , Hepacivirus/isolamento & purificação , Hepatite C Crônica/patologia , Hepatite C Crônica/virologia , Humanos , Cirrose Hepática/patologia , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resposta Viral Sustentada
10.
J Med Virol ; 90(4): 692-698, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29235129

RESUMO

Hand, foot, and mouth disease (HFMD) caused by enterovirus 71 (EV71) presents with a wide variety of clinical manifestations. Host immune response is a factor that influences disease susceptibility and severity. We investigated the potential association of gene polymorphisms in the pattern recognition receptor (PRR) pathway with the risk and severity of EV71 infection. A total of 180 EV71 HFMD cases (108 severe case; 72 mild cases) were enrolled. A group of 201 sex- and age-matched children was included as a control. All subjects were genotyped for the most common single-nucleotide polymorphisms (SNPs) in the PRR and the PRR signaling pathway using the SNPscan multiple SNP typing method. Binary logistic regression analysis revealed statistically significant differences in polymorphism of RIG-1 between patients and controls (rs3739674 G vs C: OR = 1.502, 95%CI: 1.120-2.014; rs9695310 G vs C: OR = 1.782, 95%CI: 1.312-2.419). Polymorphisms of RIG-1 rs3739674 (G vs C: OR = 2.047, 95%CI: 1.307-3.205) and TLR3 rs5743305 (A vs T: OR = 0.346, 95%CI: 0.212-0.566) were found to be associated with disease severity. The results indicated that RIG-1 (rs3739674 and rs9695310) polymorphisms are associated with an increased risk of EV71-induced HFMD in Chinese children, whereas RIG-1 rs3739674 and TLR3 rs5743305 polymorphisms are associated with disease severity. These findings support an important role of innate immune mechanism in EV71 infection.


Assuntos
Enterovirus Humano A/imunologia , Predisposição Genética para Doença , Doença de Mão, Pé e Boca/genética , Receptores de Reconhecimento de Padrão/genética , Receptores do Ácido Retinoico/genética , Índice de Gravidade de Doença , Transdução de Sinais , Povo Asiático , Criança , Pré-Escolar , China , Feminino , Técnicas de Genotipagem , Doença de Mão, Pé e Boca/patologia , Humanos , Lactente , Masculino , Polimorfismo de Nucleotídeo Único , Medição de Risco
11.
World J Gastroenterol ; 23(7): 1203-1214, 2017 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-28275300

RESUMO

AIM: To investigate the antioxidant effect of caffeic acid phenethyl ester (CAPE) in hepatic stellate cell-T6 (HSC-T6) cells cultured in vitro and the potential mechanisms. METHODS: HSC-T6 cells were cultured in vitro and treated with various concentrations of CAPE for 24, 48 and 72 h, respectively. Cell proliferation was investigated using the MTT assay, and cell ultrastructural alterations were observed by transmission electron microscopy. Flow cytometry was employed to investigate the effects of CAPE on apoptosis and the levels of reactive oxygen species in HSC-T6 cells cultured in vitro. An enzyme immunoassay instrument was used to evaluate antioxidant enzyme expression. The effect on α-smooth muscle actin was shown using immunofluorescence. Gene and protein levels of Nrf2, related factors, and mitogen activated protein kinases (MAPKs), in HSC-T6 cells were detected using RT-PCR and Western blot, respectively. RESULTS: CAPE inhibited the proliferation and activation of HSC-T6 cells cultured in vitro. CAPE increased the antioxidant levels and the translocation of Nrf2 from the cytoplasm to the nucleus in HSC-T6 cells. Moreover, the phosphorylation of MAPKs in cells decreased in response to CAPE. Interestingly, CAPE-induced oxidative stress in the cells was significantly attenuated by pretreatment with MAPKs inhibitors. CONCLUSION: CAPE inhibits cell proliferation and up-regulates the antioxidant levels in HSC-T6 cells partly through the Nrf2-MAPKs signaling pathway.


Assuntos
Antioxidantes/química , Ácidos Cafeicos/uso terapêutico , Células Estreladas do Fígado/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases , Fator 2 Relacionado a NF-E2/metabolismo , Álcool Feniletílico/análogos & derivados , Animais , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Citometria de Fluxo , Células Estreladas do Fígado/metabolismo , Técnicas Imunoenzimáticas , Microscopia de Fluorescência , Estresse Oxidativo , Fenol , Álcool Feniletílico/uso terapêutico , Transporte Proteico , Ratos , Espécies Reativas de Oxigênio/metabolismo
12.
Toxicol Res (Camb) ; 6(2): 215-222, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30090492

RESUMO

Aim: The role of phospholipid transfer protein (PLTP) in the pathogenesis of the cigarette smoke extract (CSE)-induced epithelial-to-mesenchymal transition (EMT) has not been well described. In this study we investigated the effect of PLTP on the CSE-induced EMT of rat alveolar epithelial cells (RLE-6TN). Methods: The rats were exposed to air and cigarette smoke (CS) for 3 d and then the lungs were sectioned and examined using immunohistochemistry techniques. RLE-6TN cells were treated with different concentrations of CSE. PLTP siRNA was transfected into cells or SB431542 - an inhibitor of the transforming growth factor-ß1 (TGF-ß1) type I receptor - was administered prior to CSE exposure. The expression of EMT markers and PLTP was detected by qRT-PCR. The levels of PLTP, TGF-ß1, p-Smad2, Smad2, and EMT proteins were analyzed by western blotting. Results: Lung injury and EMT were accompanied by up-regulation of PLTP and TGF-ß1 in the CS-exposed rat model. EMT was induced by CSE in vitro, and the expression of PLTP, TGF-ß1, and p-Smad2 was significantly increased after exposure to CSE (P < 0.05). Moreover, knockdown of PLTP and blocking of the TGF-ß1/Smad2 pathway restrained the CSE-induced activation of the TGF-ß1/Smad2 pathway and partly inhibited EMT by reversing E-cadherin expression and retarding the induction of N-cadherin and vimentin. In contrast, SB431542 had no effect on the expression of PLTP, while it ameliorated CSE-induced EMT. Conclusion: PLTP promotes the CSE-induced EMT process, in which the TGF-ß1/Smad2 pathway is activated.

13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(9): 2338-41, 2009 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-19950624

RESUMO

Haojiami is a very effective drug to treat malaria, and as a result of its unique drug efficacy, it is widely used in the clinical medicine. It was studied experimentally by terahertz (THz) time-domain spectroscopy (THz-TDS), and the characteristic absorption spectra were obtained in the range of 0.2 to 3.0 THz. In parallel with the experimental study, the density functional theory (DFT) and 6-31G basis set were applied to obtain the structure and vibrational frequencies of the haojiami molecule. The observed vibrational spectra were assigned according to the DFT calculations. Theoretical results show that 1.26 and 2.73 THz in significant agreement with experimental results at 1.24 and 2.73 THz. At the same time, haojiami's far infrared vibration pattern was recognized. The vibration mode takes the molecular groups skeleton vibration and the reverse as the chief feature. The results suggest that the use of the THz-TDS technique can be an effective way to inspect for Chinese medicine, and provide the theory basis for further study of the haojiami drug efficacy.

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