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1.
Int J Mol Sci ; 23(9)2022 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-35563474

RESUMEN

A study of 250 commercial drugs to act as corrosion inhibitors on steel has been developed by applying the quantitative structure-activity relationship (QSAR) paradigm. Hard-soft acid-base (HSAB) descriptors were used to establish a mathematical model to predict the corrosion inhibition efficiency (IE%) of several commercial drugs on steel surfaces. These descriptors were calculated through third-order density-functional tight binding (DFTB) methods. The mathematical modeling was carried out through autoregressive with exogenous inputs (ARX) framework and tested by fivefold cross-validation. Another set of drugs was used as an external validation, obtaining SD, RMSE, and MSE, obtaining 6.76%, 3.89%, 7.03%, and 49.47%, respectively. With a predicted value of IE% = 87.51%, lidocaine was selected to perform a final comparison with experimental results. By the first time, this drug obtained a maximum IE%, determined experimentally by electrochemical impedance spectroscopy measurements at 100 ppm concentration, of about 92.5%, which stands within limits of 1 SD from the predicted ARX model value. From the qualitative perspective, several potential trends have emerged from the estimated values. Among them, macrolides, alkaloids from Rauwolfia species, cephalosporin, and rifamycin antibiotics are expected to exhibit high IE% on steel surfaces. Additionally, IE% increases as the energy of HOMO decreases. The highest efficiency is obtained in case of the molecules with the highest ω and ΔN values. The most efficient drugs are found with pKa ranging from 1.70 to 9.46. The drugs recurrently exhibit aromatic rings, carbonyl, and hydroxyl groups with the highest IE% values.


Asunto(s)
Lidocaína , Relación Estructura-Actividad Cuantitativa , Corrosión , Espectroscopía Dieléctrica , Lidocaína/farmacología , Acero/química
2.
Br J Ophthalmol ; 102(10): 1320-1323, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29945895

RESUMEN

PURPOSE: To determine the prevalence of refractive errors in Colombia and its relations with demographic and socioeconomic variables. METHODS: A cross-sectional study performed in 10 Colombian administrative districts (MIOPUR study), including children and adolescents from 8 to 17 years old and adults from 35 to 55 years old. RESULTS: 3608 individuals (100% of whom agreed to participate) were included. Prevalence estimates of refractive errors were: hyperopia 32.3% (95% CI 30.7 to 33.8), myopia 12.9% (95% CI 11.8 to 14.0), mixed astigmatism 2.8% (95% CI 2.2 to 3.3) and anisometropia 1.9% (95% CI 1.4 to 2.3). Prevalence of myopia in 15-year-old adolescents was 14.7%. In children and adolescents, the hyperopia prevalence decreased while myopia prevalence increased with age. In the adults group, the tendency was the contrary. Myopia prevalence reached 15.7% in urban and 9.2% in rural areas, and for hyperopia, the rates were 29.4% in urban and 36.1% in rural areas. In the multivariate analysis, living in an urban area significantly increased the risk of having myopia (OR: 1.45 (1.12 to 1.89); p<0.01). There were significant regional differences among diverse zones of the country. CONCLUSIONS: Prevalence estimates of myopia and hyperopia in Colombia were found to be at an intermediate point compared with global data. In adults, myopia frequency was lower than in European and Asian studies. The prevalence of myopia increased during childhood and adolescence and was higher in middle-aged adults (35-39 years) than in older adults. On the other hand, hyperopia rates increased with age, findings that suggest a cohort effect. In the multivariate analysis, residence in urban areas and living in a medium-high socioeconomic status were linked to myopia.


Asunto(s)
Refracción Ocular , Errores de Refracción/epidemiología , Población Rural , Población Urbana , Agudeza Visual , Adolescente , Adulto , Distribución por Edad , Niño , Colombia/epidemiología , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Errores de Refracción/fisiopatología , Estudios Retrospectivos , Factores de Riesgo , Distribución por Sexo , Adulto Joven
3.
Arq Bras Oftalmol ; 80(6): 359-363, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29267570

RESUMEN

PURPOSE: The aim of this study was to establish the frequency of refractive errors in children and adolescents aged between 8 and 17 years old, living in the metropolitan area of Bucaramanga (Colombia). METHODS: This study was a secondary analysis of two descriptive cross-sectional studies that applied sociodemographic surveys and assessed visual acuity and refraction. Ametropias were classified as myopic errors, hyperopic errors, and mixed astigmatism. Eyes were considered emmetropic if none of these classifications were made. The data were collated using free software and analyzed with STATA/IC 11.2. RESULTS: One thousand two hundred twenty-eight individuals were included in this study. Girls showed a higher rate of ametropia than boys. Hyperopic refractive errors were present in 23.1% of the subjects, and myopic errors in 11.2%. Only 0.2% of the eyes had high myopia (≤-6.00 D). Mixed astigmatism and anisometropia were uncommon, and myopia frequency increased with age. There were statistically significant steeper keratometric readings in myopic compared to hyperopic eyes. CONCLUSIONS: The frequency of refractive errors that we found of 36.7% is moderate compared to the global data. The rates and parameters statistically differed by sex and age groups. Our findings are useful for establishing refractive error rate benchmarks in low-middle-income countries and as a baseline for following their variation by sociodemographic factors.


Asunto(s)
Errores de Refracción/epidemiología , Adolescente , Niño , Colombia/epidemiología , Estudios Transversales , Femenino , Humanos , Masculino , Errores de Refracción/clasificación , Población Urbana
5.
Arq. bras. oftalmol ; Arq. bras. oftalmol;80(6): 359-363, Nov.-Dec. 2017. tab, graf
Artículo en Inglés | LILACS | ID: biblio-888162

RESUMEN

ABSTRACT Purpose: The aim of this study was to establish the frequency of refractive errors in children and adolescents aged between 8 and 17 years old, living in the metropolitan area of Bucaramanga (Colombia). Methods: This study was a secondary analysis of two descriptive cross-sectional studies that applied sociodemographic surveys and assessed visual acuity and refraction. Ametropias were classified as myopic errors, hyperopic errors, and mixed astigmatism. Eyes were considered emmetropic if none of these classifications were made. The data were collated using free software and analyzed with STATA/IC 11.2. Results: One thousand two hundred twenty-eight individuals were included in this study. Girls showed a higher rate of ametropia than boys. Hyperopic refractive errors were present in 23.1% of the subjects, and myopic errors in 11.2%. Only 0.2% of the eyes had high myopia (≤-6.00 D). Mixed astigmatism and anisometropia were uncommon, and myopia frequency increased with age. There were statistically significant steeper keratometric readings in myopic compared to hyperopic eyes. Conclusions: The frequency of refractive errors that we found of 36.7% is moderate compared to the global data. The rates and parameters statistically differed by sex and age groups. Our findings are useful for establishing refractive error rate benchmarks in low-middle-income countries and as a baseline for following their variation by sociodemographic factors.


RESUMO Objetivo: O objetivo deste estudo foi estabelecer a frequência de erros refrativos em crianças e adolescentes com idade entre 8 e 17 anos, residentes na região metropolitana de Bucaramanga (Colômbia). Métodos: Este estudo foi uma análise secundária de dois estudos descritivos transversais que aplicaram levantamentos sociodemográficos e avaliaram a acuidade e a refração visuais. As ametropias foram classificadas como erros miopicos, erros hipermetrópicos e astigmatismo misto. Os olhos eram considerados emétropes se nenhuma dessas classificações fosse feita. Os dados foram coletados usando software livre e analisados com STATA/IC 11.2. Resultados: Mil e duzentos e vinte e oito indivíduos foram incluídos neste estudo. As meninas mostraram uma maior taxa de ametropia do que os meninos. Erros refrativos hipermetrópicos estavam presentes em 23,1% dos indivíduos e erros miópicos em 11,2%. Apenas 0,2% dos olhos apresentavam miopia alta (≤-6,00 D). O astigmatismo misto e a anisometropia eram incomuns e a frequência de miopia aumentava com a idade. Houve leituras queratométricas mais acentuadas estatisticamente significativas em míopes em comparação com os olhos hipermétropes. Conclusões: A frequência de erros de refração que encontramos em 36,7% é moderada em comparação com os dados globais. As taxas e os parâmetros diferiram estatisticamente por sexo e grupos etários. Nossas descobertas são úteis para estabelecer padrões de referência de erro de refração em países de baixa renda média e como base para seguir sua variação por fatores sociodemográficos.


Asunto(s)
Humanos , Masculino , Femenino , Niño , Adolescente , Errores de Refracción/epidemiología , Errores de Refracción/clasificación , Población Urbana , Estudios Transversales , Colombia/epidemiología
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