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1.
Heliyon ; 10(9): e30243, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38707413

RESUMO

The emerging markets in the ASEAN region, such as Indonesia, Malaysia, the Philippines, Thailand and Vietnam, have put great effort into achieving dual objectives: (i) supporting economic growth and (ii) combating environmental degradation simultaneously. These objectively depend on the fast urbanization taking place in these countries. While increased energy consumption from urbanization supports economic growth, urbanization is a key driver of environmental degradation. This paper examines a potential link between urbanization and renewable energy consumption, primarily ignored in current literature, particularly in the ASEAN-5 countries. Findings from this paper indicate that, despite the adverse effect of urbanization on renewable energy consumption in the short run, a positive effect is found in the long run for these emerging ASEAN markets, except Malaysia. The Philippines appears to balance well between urbanization and renewable energy consumption in the short and long run. Policy implications have emerged based on the findings of this paper.

2.
Heliyon ; 10(8): e28657, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38628730

RESUMO

This study revisits the feedback effect from foreign direct investments (FDI) on environmental regulations under the presence of the host country's political structure. Such a relationship may encounter the endogeneity problem due to the omitted variable bias and reverse causality. As such, the two-step system generalized method of moments is employed. Using data from 21 OECD countries from 1990 to 2019, we confirm that FDI flows influence environmental regulations, but such an effect is conditional on the host country's political constraints. Specifically, FDI increases (decreases) the stringency of environmental regulations if domestic political constraints are sufficiently high (low). Understanding the mechanisms of how FDI flows can affect environmental regulations allows countries to revise their policies to attract more FDI flows to support economic growth while simultaneously minimising their negative effects on the environment.

3.
Heliyon ; 10(3): e25143, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38317947

RESUMO

This paper investigates the impact of US economic policy uncertainty and geopolitical risk on the return spillovers among 24 sectors in Vietnam from April 13, 2017, to April 8, 2022. The VAR-based connectedness approach and quantile techniques are employed in this study. Empirical results from the study reveal that an increase in US economic policy uncertainty significantly impacts return spillovers. However, this impact is only observed during periods of heightened uncertainty in US economic policy. Economic policy uncertainty plays a more prominent role in affecting the spillovers across Vietnamese sectors compared to geopolitical risk. Findings from our analysis also highlight the crucial role of the banking sector as a transmitter of risk in the Vietnamese stock market.

4.
PLoS One ; 19(2): e0297431, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38306358

RESUMO

Financial inclusion is pivotal in supporting sustainable economic growth and social transformation. It is a key enabler for reducing poverty and uplifting prosperity. Improving financial inclusion has attracted significant attention from practitioners, academics, and governments. However, the asymmetric effect of institutional quality on financial inclusion contingent upon the income level has largely been neglected in the existing literature. As such, this study examines this asymmetric effect using the panel smooth transition regression for a sample of 110 countries globally from 2004 to 2020. Our empirical findings confirm the asymmetric effect of institutional quality on financial inclusion depending on the income level. Improved institutional quality is associated with extended financial inclusion in high-income and middle-income countries. However, low-income countries may not benefit from their institutional reform. Policy implications have emerged based on these empirical findings.


Assuntos
Renda , Pobreza , Instalações de Saúde , Desenvolvimento Econômico , Políticas , Dióxido de Carbono
5.
Cancer Biomark ; 39(4): 289-298, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38250760

RESUMO

High grade epithelial ovarian carcinoma is an aggressive tumor. Treatment includes platinum therapy, however it recurs in most patients due to therapy resistance. In this project, we study the immunohistochemical (IHC) expression of five potential biomarkers/prognostic markers in high grade epithelial ovarian carcinoma: EGFR, HLA-G, CD70, c-MET, and NY-ESO1. A cohort of 274 patients is used. We compare the IHC expression with age, stage, ascites status, family history of cancer, disease free survival (DFS) and overall survival (OS). EGFR expression is significantly correlated with family history and worse OS. HLA-G is associated with worse OS. To confirm the results of EGFR and HLA-G, a second separated cohort of 248 patients is used. Positive EGFR expression again shows worse OS, while HLA-G expression has worse prognostic trend. CD70 has a worse OS trend. C-MET and NY-ESO1 do not have any clinical correlations. EGFR can potentially serve as target in future clinical immune therapy trials.


Assuntos
Antígenos de Neoplasias , Biomarcadores Tumorais , Carcinoma Epitelial do Ovário , Receptores ErbB , Antígenos HLA-G , Proteínas de Membrana , Neoplasias Ovarianas , Proteínas Proto-Oncogênicas c-met , Humanos , Feminino , Biomarcadores Tumorais/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Proto-Oncogênicas c-met/metabolismo , Receptores ErbB/metabolismo , Carcinoma Epitelial do Ovário/patologia , Carcinoma Epitelial do Ovário/metabolismo , Carcinoma Epitelial do Ovário/mortalidade , Pessoa de Meia-Idade , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/mortalidade , Prognóstico , Antígenos de Neoplasias/metabolismo , Antígenos HLA-G/metabolismo , Idoso , Adulto , Gradação de Tumores , Imuno-Histoquímica , Idoso de 80 Anos ou mais
6.
Heliyon ; 10(1): e23977, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38234912

RESUMO

Understanding the energy transition process in developing countries is crucial to implement policies to reduce the use of traditional fossil fuel-based energy sources, which increase pollution, worsen global climate change, and negatively impact people's health. Existing literature indicates that households account for approximately 25% of total energy consumption for consumption and production activities. However, understanding the energy consumption patterns of choices of energy sources and their determinants has largely been neglected in the existing literature. As such, this study uses the multivariate probit model to identify the factors influencing household energy choices in Vietnam, using data from 2016 to 2020 from the Vietnamese Households Living Standard Surveys (VHLSS). Our study focuses on how households' multiple occupations, particularly in rural areas, affect energy sources choices. We find that households participate in different agricultural sub-sectors simultaneously, resulting in differential access to multiple energy sources. Households engaging in cultivation, forestry, and animal husbandry activities are more likely to choose coal, fuelwood, and biomass as the primary energy sources for production and daily uses. In contrast, higher household income and household head with higher education level also increases the likelihood of choosing cleaner energy choices for daily uses and production activities. In addition, our empirical findings confirm the validity of the "energy stacking" hypothesis rather than the "energy ladders" hypothesis - two contrasting hypotheses concerning household energy transition in the literature. Policy implications have emerged based on the findings of this paper to enhance the clean energy transition in Vietnam in achieving sustainable economic development and social transformation and her commitment to combating global climate change issues.

7.
Eur J Med Chem ; 265: 116122, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38199164

RESUMO

Two series of N-(heteroaryl)thiophene sulfonamides, encompassing either a methylene imidazole group or a tert-butylimidazolylacetyl group in the meta position of the benzene ring, have been synthesized. An AT2R selective ligand with a Ki of 42 nM was identified in the first series and in the second series, six AT2R selective ligands with significantly improved binding affinities and Ki values of <5 nM were discovered. The binding modes to AT2R were explored by docking calculations combined with molecular dynamics simulations. Although some of the high affinity ligands exhibited fair stability in human liver microsomes, comparable to that observed with C21 undergoing clinical trials, most ligands displayed a very low metabolic stability with t½ of less than 10 min in human liver microsomes. The most promising ligand, with an AT2R Ki value of 4.9 nM and with intermediate stability in human hepatocytes (t½ = 77 min) caused a concentration-dependent vasorelaxation of pre-contracted mouse aorta.


Assuntos
Receptor Tipo 2 de Angiotensina , Sulfonamidas , Camundongos , Humanos , Animais , Receptor Tipo 2 de Angiotensina/metabolismo , Ligantes , Sulfonamidas/química , Tiofenos/química , Aorta/metabolismo , Angiotensina II/metabolismo
8.
Arch Environ Contam Toxicol ; 86(1): 48-57, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38063883

RESUMO

The seeds of Annona glabra L., an invasive plant in Vietnam, were first employed as a new biosorbent for the adsorption of methylene blue (MB) from aqueous media. The characterizations of the material using FT-IR, SEM, nitrogen adsorption-desorption analysis, and point of zero charge reveals that it possesses a rough and irregular surface, various polar functional groups, and pHpzc of 5.5. Certain adsorption conditions including adsorbent dose, solution pH, contact time, and initial concentration of MB were found to affect adsorption efficiency. The kinetic data are well fitted with pseudo-second-order model with the adsorption rate of 0.002 g mg-1 min-1 and initial rate of 4.46 mg g-1 min-1. For the adsorption isotherm, three nonlinear models were used to analyze the experiment data, including Langmuir, Freundlich, and Temkin. The results indicate that the Langmuir model best describes the adsorption of Annona glabra L. seeds powder (AGSP) with a maximum adsorption capacity of 98.0 mg g-1. The investigation underpins the adsorption mechanism, whereby the electrostatic attraction between positively charged MB and negatively charged surface of AGSP is expected to be the predominant mechanism, together with hydrogen bonding and pi-pi interaction. These results make AGSP an interesting biosorbent concerning its environmental friendliness, cost-effectiveness, and relatively high dye adsorption capacity.


Assuntos
Annona , Poluentes Químicos da Água , Azul de Metileno/análise , Azul de Metileno/química , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/análise , Concentração de Íons de Hidrogênio , Sementes/química , Adsorção , Cinética
9.
Eur Radiol ; 34(2): 810-822, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37606663

RESUMO

OBJECTIVES: Non-contrast computed tomography of the brain (NCCTB) is commonly used to detect intracranial pathology but is subject to interpretation errors. Machine learning can augment clinical decision-making and improve NCCTB scan interpretation. This retrospective detection accuracy study assessed the performance of radiologists assisted by a deep learning model and compared the standalone performance of the model with that of unassisted radiologists. METHODS: A deep learning model was trained on 212,484 NCCTB scans drawn from a private radiology group in Australia. Scans from inpatient, outpatient, and emergency settings were included. Scan inclusion criteria were age ≥ 18 years and series slice thickness ≤ 1.5 mm. Thirty-two radiologists reviewed 2848 scans with and without the assistance of the deep learning system and rated their confidence in the presence of each finding using a 7-point scale. Differences in AUC and Matthews correlation coefficient (MCC) were calculated using a ground-truth gold standard. RESULTS: The model demonstrated an average area under the receiver operating characteristic curve (AUC) of 0.93 across 144 NCCTB findings and significantly improved radiologist interpretation performance. Assisted and unassisted radiologists demonstrated an average AUC of 0.79 and 0.73 across 22 grouped parent findings and 0.72 and 0.68 across 189 child findings, respectively. When assisted by the model, radiologist AUC was significantly improved for 91 findings (158 findings were non-inferior), and reading time was significantly reduced. CONCLUSIONS: The assistance of a comprehensive deep learning model significantly improved radiologist detection accuracy across a wide range of clinical findings and demonstrated the potential to improve NCCTB interpretation. CLINICAL RELEVANCE STATEMENT: This study evaluated a comprehensive CT brain deep learning model, which performed strongly, improved the performance of radiologists, and reduced interpretation time. The model may reduce errors, improve efficiency, facilitate triage, and better enable the delivery of timely patient care. KEY POINTS: • This study demonstrated that the use of a comprehensive deep learning system assisted radiologists in the detection of a wide range of abnormalities on non-contrast brain computed tomography scans. • The deep learning model demonstrated an average area under the receiver operating characteristic curve of 0.93 across 144 findings and significantly improved radiologist interpretation performance. • The assistance of the comprehensive deep learning model significantly reduced the time required for radiologists to interpret computed tomography scans of the brain.


Assuntos
Aprendizado Profundo , Adolescente , Humanos , Radiografia , Radiologistas , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Adulto
10.
PLoS One ; 18(12): e0290680, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38096228

RESUMO

This study examines the market return spillovers from the US market to 10 Asia-Pacific stock markets, accounting for approximately 91 per cent of the region's GDP from 1991 to 2022. Our findings indicate an increased return spillover from the US stock market to the Asia-Pacific stock market over time, particularly after major global events such as the 1997 Asian and the 2008 global financial crises, the 2015 China stock market crash, and the COVID-19 pandemic. The 2008 global financial crisis had the most substantial impact on these events. In addition, the findings also indicate that US economic policy uncertainty and US geopolitical risk significantly affect spillovers from the US to the Asia-Pacific markets. In contrast, the geopolitical risk of Asia-Pacific countries reduces these spillovers. The study also highlights the significant impact of information and communication technologies (ICT) on these spillovers. Given the increasing integration of global financial markets, the findings of this research are expected to provide valuable policy implications for investors and policymakers.

11.
Heliyon ; 9(12): e22836, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38094065

RESUMO

Asians believe that education plays a crucial role in earning higher income for individuals and accumulating larger wealth for households. Educational achievements have been generally considered an indicator of success. However, gender bias in favour of males as the household heads still exists in Asian societies due to the significant influence of Confucian belief. This study investigates the independent effect of education and gender of the households' heads and their joint effect on household wealth in the Vietnamese context in the most recent decade using data from the Vietnam Household Living Standards Surveys (VHLSSs) between 2010 and 2020. Our study uses quantile regression and propensity score matching methods to ensure the robustness of the empirical results. We find that the education of the household heads contributed to increased household wealth in Vietnam in 2010 and 2020. However, household wealth decreases across different wealth quantiles when the households' heads are females. These findings confirm the currently deep-rooted gender stereotypes and a 'gendered structure' economy in Vietnam and require attention from the Vietnamese government. In addition, our empirical results reveal that being a female as the household head with a degree/certificate from a general education will increase household wealth. Our empirical results have largely been consistent across different wealth distributions.

12.
PLoS One ; 18(11): e0293033, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38011050

RESUMO

Fintech development is generally considered as an effective mechanism to promote the consumption of renewable energy sources. The relationship between fintech development and renewable energy consumption have been examined in previous studies. However, the moderating effect of income inequality on this relationship has largely been ignored in the existing literature. As such, this study is conducted to shed light on this moderating effect. Two estimation techniques, including the two-step system generalized method of moments (GMM) and the method of moments quantile regression (MMQR), were used on a sample of 65 countries from 2013 to 2019. Our findings reveal that fintech development plays a vital role in promoting the consumption of renewable energy sources. However, it is crucial to recognize that rising income inequality may hinder the potential positive effects of fintech development on renewable energy consumption. A threshold of income inequality should be maintained to ensure that the positive effect of fintech development on increased renewable energy consumption is not compromised. Policy implications have emerged based on the findings from this study regarding promoting fintech development towards green economic growth and sustainable development.


Assuntos
Dióxido de Carbono , Renda , Energia Renovável , Desenvolvimento Econômico , Desenvolvimento Sustentável
13.
Open Heart ; 10(2)2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38011990

RESUMO

OBJECTIVE: This study aimed to assess the incidence of early cancer therapy-related cardiac dysfunction (CTRCD) and the characteristics of left and right heart deformations during anthracycline chemotherapy. METHODS: We prospectively enrolled a cohort of 351 chemotherapy-naïve women with breast cancer and cardiovascular risk factors who were scheduled to receive anthracycline. The left ventricular ejection fraction (LVEF), left ventricular global longitudinal strain (LV-GLS) and right ventricular and left atrial longitudinal strains were evaluated using echocardiography at baseline, before every subsequent cycles and at 3 weeks after the final anthracycline dose. CTRCD was defined as a new LVEF reduction by ≥10 percentage points to an LVEF<50% and/or a new relative decline in GLS by >15% from the baseline value. RESULTS: Eighteen (5.1%) patients had evidence of asymptomatic CTRCD during anthracycline treatment, and 50% developed CTRCD before completing the chemotherapy regimen. In the CTRCD group, while LV-GLS decrease significantly after the first dose of anthracycline, the reduction of right ventricular free-wall longitudinal strain and left atrial reservoir strain were observed after the second dose. Other strain indices could not be used to identify early CTRCD. CONCLUSIONS: Cardiotoxicity appeared soon after the initiation of anthracycline chemotherapy. Among the left-heart and right-heart mechanics, LV-GLS remains the best deformation indicator for detecting early CTRCD.


Assuntos
Fibrilação Atrial , Neoplasias da Mama , Cardiopatias , Disfunção Ventricular Esquerda , Humanos , Feminino , Antraciclinas/efeitos adversos , Função Ventricular Esquerda , Volume Sistólico , Fibrilação Atrial/complicações , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Esquerda/diagnóstico por imagem , Detecção Precoce de Câncer/efeitos adversos , Cardiopatias/diagnóstico , Cardiopatias/diagnóstico por imagem , Neoplasias da Mama/induzido quimicamente , Neoplasias da Mama/complicações , Neoplasias da Mama/tratamento farmacológico
14.
PLoS One ; 18(11): e0294104, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37917780

RESUMO

[This corrects the article DOI: 10.1371/journal.pone.0285279.].

15.
Environ Sci Pollut Res Int ; 30(53): 114249-114263, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37861823

RESUMO

The Association of Southeast Asian Nations (ASEAN), a new global economic force, has struggled to achieve a dual objective of enhanced economic growth and improved environmental quality. Financial development is generally considered an important tool in achieving these simultaneous objectives. This paper examines the response mechanism and the inter-relationship between the ASEAN region's financial development, energy consumption, and economic growth. Unlike previous studies, the paper uses a generalized method of moments panel vector autoregression (GMM-panel VAR) framework for the 1981-2021 period. The second-generation Granger causality test is used to identify their causality relationship. Economic growth supports financial development and reduces energy consumption from fossil fuel sources in the ASEAN countries. Financial development also reduces fossil fuel energy consumption. The bi-directional relationship between economic growth and fossil fuel energy consumption exists. Energy consumption and financial development are also bi-directionally linked. However, only the unidirectional Granger causality from economic growth to financial development is found. The variance decomposition analysis results confirm that economic growth accounts for the most significant variance in fossil fuel energy consumption and financial development in the ASEAN countries. Policy implications have emerged based on these findings.


Assuntos
Dióxido de Carbono , Desenvolvimento Econômico , Dióxido de Carbono/análise , Ásia , Fontes Geradoras de Energia , Combustíveis Fósseis , Energia Renovável
16.
PLoS One ; 18(9): e0291020, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37656687

RESUMO

Various studies have been conducted to measure financial inclusion at the country level. However, measuring financial inclusion at the household level has largely been neglected in the existing literature, particularly for emerging markets such as Vietnam. This study constructs an index of financial inclusion at the household level using the Vietnam Household Living Standard Surveys (VHLSS) in 2014, 2016, and 2018. We also identify the determinants of financial inclusion from the perspective of Vietnamese households. Our study also utilizes an ordered logit model to examine the effects of the determinants on each level of financial inclusion. Our empirical results reveal three key determinants, including (i) total income per household, (ii) relative income representing the difference between the average income of the province that the household currently lives in and the total income of this household, and (iii) the distance from the household to the nearest bank branch, are crucial factors driving the financial inclusion. While the total income per household positively enhances financial inclusion, relative income appears to reduce the degree of financial inclusion. Besides, distance to the nearest bank branch poses another challenge in achieving the financial inclusion goals in Vietnam in the future.


Assuntos
Renda , Vietnã , Modelos Logísticos
17.
Heliyon ; 9(8): e19000, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37636424

RESUMO

Income inequality is a vexing developmental challenge for governments and policymakers as it impedes social transformation and economic growth and development. Meanwhile, promoting financial development is generally regarded as an effective way to achieve inclusive and sustainable growth. This study examines the long-run effects of financial development, economic growth, and their combined effects on income inequality for 12 Asia-Pacific countries from 1990 to 2021. This paper employs various econometric techniques and different financial development proxies to ensure the findings' robustness. The paper also constructs a financial development index using the principal component analysis to fully capture the comprehensive effect of financial development on income inequality. Empirical results reveal that the impact of financial development on income inequality follows the inverted U-shaped relationship - financial development widens income inequality and only reduces income when surpassing its turning point. Findings further reveal that the nonlinear effect of financial development on income inequality is contingent upon the level of per capita income. Thus, policies promoting financial development to reduce income inequality should consider the existing level of per capita income.

18.
Front Surg ; 10: 1224931, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37545842

RESUMO

Introduction: This study aimed to elucidate the magnetic resonance (MR) characteristics of anal fistulas extending to the scrotum, and the applicable rules, and to correlate MR features with surgical findings. Methods: We conducted a retrospective study in 150 consecutive patients with anal fistulas extending into the scrotum, who were diagnosed and underwent surgery at University Medical Center Ho Chi Minh City between January 2017 and April 2022. MR findings were evaluated and compared with surgical findings using Cohens kappa coefficient (k) with a 95% confidence interval. Results: 150 patients (mean age 37.6 ± 10.9 years) with 166 fistulas, including 150 anal fistulas with scrotal extension. Most fistulas were low transsphincteric (80.0%, 120/150 patients). There was a strong agreement for primary tract classification and detecting the location of internal openings between MRI and surgical findings with k = 0.83 (0.780.87) and k = 0.89 (0.85 0.93) (p<0.001), respectively. There is a significant correlation between the location of internal openings and the type of fistula (p<0.05). Low transsphincteric fistulas were predominant in the anterior group (103/122 patients vs. 10/19 patients), while in the posterior group, it was more common in the high transsphincteric fistulas (7/19 patients vs. 14/122 patients), and the intersphincteric fistulas (1/19 patients vs. 5/122 patients); and the suprasphincteric fistulas were only seen in the posterior group (1 patient). Conclusion: Anal fistulas with scrotal extension are exceptions to Goodsalls rule. Albeit long-tract fistulas, most are low transsphincteric and have anterior internal openings.

19.
PLoS One ; 18(7): e0288621, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37467279

RESUMO

In 2021, when the Covid-19 pandemic had a severe impact on the economy, a significant number of enterprises in Vietnam temporarily suspended doing business. Previous studies have focused on either model for predicting bankruptcy and financial distress or measuring market risk during extreme events. The effects of market risk and financial distress on a firm's performance have largely been ignored in the literature, particularly in Vietnam. This study examines the effects of market risk, measured using the conditional value-at-risk technique and financial distress proxied by the interest coverage ratio (ICR) on firm performance for 500 nonfinancial listed firms in Vietnam from 2012 to 2021. We also estimate the optimal ICR for Vietnam's listed firms. Two estimation techniques are used: dynamic panel models (two-step difference-and system-generalized method of moments) and panel threshold regression. We find that increased market risk reduces firm performance. However, a higher ICR (lower financial distress) also improves a firm's performance. With increased market risk, the financial performance of firms with a high ICR deteriorates significantly.


Assuntos
COVID-19 , Pandemias , Humanos , Vietnã/epidemiologia , COVID-19/epidemiologia , Comércio , Falência da Empresa
20.
Eur J Med Chem ; 257: 115419, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37301076

RESUMO

Development of subtype-selective leads is essential in drug discovery campaigns targeting G protein-coupled receptors (GPCRs). Herein, a structure-based virtual screening approach to rationally design subtype-selective ligands was applied to the A1 and A2A adenosine receptors (A1R and A2AR). Crystal structures of these closely related subtypes revealed a non-conserved subpocket in the binding sites that could be exploited to identify A1R selective ligands. A library of 4.6 million compounds was screened computationally against both receptors using molecular docking and 20 A1R selective ligands were predicted. Of these, seven antagonized the A1R with micromolar activities and several compounds displayed slight selectivity for this subtype. Twenty-seven analogs of two discovered scaffolds were designed, resulting in antagonists with nanomolar potency and up to 76-fold A1R-selectivity. Our results show the potential of structure-based virtual screening to guide discovery and optimization of subtype-selective ligands, which could facilitate the development of safer drugs.


Assuntos
Adenosina , Antagonistas de Receptores Purinérgicos P1 , Antagonistas de Receptores Purinérgicos P1/farmacologia , Antagonistas de Receptores Purinérgicos P1/química , Simulação de Acoplamento Molecular , Ligantes , Sítios de Ligação , Receptor A2A de Adenosina/metabolismo , Receptor A1 de Adenosina/metabolismo , Antagonistas do Receptor A2 de Adenosina/farmacologia , Antagonistas do Receptor A2 de Adenosina/química
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