Bibliometric reviews, carried out from access to databases of scientific articles associated with software for data processing, can be helpful for qualitative and quantitative assessments of existing publications on a given topic. Several petroleum hydrocarbons are carcinogenic and immunotoxic agents, causing adverse effects on the biota, and the study of metabolites generated in bioremediation processes has been the object of current research. Therefore, in this work, the use of bibliometric analysis as a tool for surveying studies on the applied metabolomics bioremediation of areas impacted by hydrocarbons is presented. A bibliometric review was carried out in the Scopus Preview and Web of Science databases with data analysis using RStudio software with the bibliometrix package. The survey gathered the studies and prominent publications of the last seven years, making it possible to present gaps and opportunities in the area. reviews processing topic agents biota research Therefore work presented package years area

The present work aimed to direct amino acid (AA) sensing by quantum dots (QD) and development of an analytical method for potential fast clinical tests. Notably, AA with a positive charge or neutral polar chains, namely L-histidine (His) and L-threonine (Thr), responded to glutathione-coated CdTe (GSH-CdTe) (ΔF ≤ 90%, variation of fluorescence intensity). However, in ammoniacal buffer (0.25 mol L-1) at pH 8.0, 2.2 nm GSH-CdTe responded only to His. Static quenching with complex association constant (Ksv) varying from 2.81 to 0.94 (10 L mol-1) as well as van der Waals forces and/or hydrogen bonding were predicted for His-QD quenching mechanism and binding type. Additionally, thermodynamic parameters as ΔH = -76.5 kJ mol-1 (enthalpy), ΔS = -227.4 J K-1 mol-1 (entropy) and ΔG from -9.8 until -6.4 kJ mol-1 (Gibbs free energy) at 20 to 35 °C were estimated by van’t Hoff equation. Under optimal conditions, the developed method presented a linear range from 0.42 to 35 mmol L-1 (with correlation coefficient (r) of 0.9970, n = 7), good precision (relative standard deviations (RSD) < 2.5% for 2.5 and 20 mmol L-1; n = 6) and limit of detection 1.6 × 10-4 mol L-1 (0.025 mg mL-1). Recovery tests were performed on artificial urine and human urine samples with recoveries ranging from 78.7 to 127.6%.

The development of a method based on extraction induced by emulsion breaking (EIEB) aiming copper determination in gasohol using graphite furnace atomic absorption spectrometry (GF AAS) is reported. Emulsification of the gasohol samples was carried out using nitric acid solution, (1,1,3,3-tetramethylbutyl)phenyl-polyethylene glycol surfactant (Triton X-114), and ultrasound energy. The variables related to the extraction efficiency were optimized by multivariate approaches (two-level factorial fractional design and Doehlert design). The best results were obtained when the emulsion was formed with 5.0 mL of the sample, 0.200 mL of 2.4 mol L-1 HNO3, 0.100 mL of 10% Triton X-114 and 10 min of sonication. A fast and efficient emulsion breaking was performed at 90 ºC. A volume of 6.65 mL of the copper-rich hydroalcoholic phase was extracted, separated from the organic phase and analyzed. Under these conditions, the following analytical characteristics were obtained: 0.61 and 2.0 µg L-1 for limits of detection and quantification, respectively; precision (percentage of relative standard deviation, 10 µg L-1) of 2.8%; and analytical sensitivity of 0.011 L µg -1. Accuracy was assessed by spike tests, and values in the range of 95-110% were achieved. The method was applied in the determination of copper in Brazilian gasoline samples (gasohol with 27% ethanol).

Levulinic acid is a reactive polar organic compound deemed as a building block for several products with relevant applications, replacing traditional substances in the petrochemical industry. Considered a platform molecule, levulinic acid is industrially produced from the acid hydrolysis of biomass - mainly plant-based - using hydrochloric or sulfuric acid in homogenous catalysis. However, considering the World Market for levulinic acid is expected to reach US$ 71.9 million in 2027, growing annually at 14.1%, and its applications in agriculture, pharmaceuticals, plasticizers, cosmetics, and food additives, the development of alternative production processes is sought. Hence, a survey was performed on publications considering the alternatives for biomass-based levulinic acid production processes: I) alternative homogenous catalysts to avoid using noble materials in the reactor; II) heterogeneous catalysis to facilitate and reduce the catalyst’s separation and recovery costs; III) ionic liquids, exploiting their high solvency, stability, and catalytic capacity. Additionally, biomass alternatives for obtaining levulinic acid are presented, showing that other agricultural residues and animal biomass options are being considered, targeting process flexibilization while reducing costs and producing derivatives at more competitive prices. Thus, it can be stated that levulinic acid is an important platform molecule for biorefineries’ economics, replacing fossil fuels with renewable raw materials.

Itaconic acid (IA) is a very promising platform molecule due to the possibility of it being used to obtain products such as methyl methacrylate and synthetic latex, with the prospect that its global market will grow at an average annual rate of 2.8% (CAGR) from 2021 to 2026, exceeding US$ 116.6 million in sales. The main technological route used to obtain itaconic acid is fermentation using different strains of Aspergillus terreus fungi. The main advancements are related to genetic engineering, as Aspergillus terreus is the most tolerant of the microorganisms employed in the process synthesis and optimization. The main substrate used is glucose (52%), followed by glycerol (25%). Among the results presented in this paper, the best production was achieved using Ustilago maydis, with 220 g L-1 of IA, yielding 0.33 g g-1, using glucose as a carbon source. Moreover, it is necessary to continue optimizing the biological process of IA production, since it is a platform molecule with major economic potential.

Cloud point extraction (CPE) in association with graphite furnace atomic absorption spectrometry (GF AAS) was proposed for preconcentration and quantification of trace amounts of copper and cadmium in samples of saline produced formation water from petroleum exploration. The procedure was based on the formation of hydrophobic complexes of the analytes with 1,5-diphenylthiocarbazone (dithizone) in a micellar media of the surfactant (1,1,3,3-tetramethyl butyl) phenyl-polyethylene glycol (Triton X-114). Constrained mixture design was performed for the optimization of the proportions of the three solutions employed in the CPE: Triton X-114, dithizone, and buffer solution. Under the recommended conditions, the CPE GF AAS procedure allowed to obtain enrichment factors of 18 and 11 times, limits of quantification of 0.030 and 0.12 µg L-1 and precision, expressed as relative standard deviation (RSD, n = 8, 2.0 µg L-1), of 1.1 and 4.3% for copper and cadmium, respectively. The CPE GF AAS method was applied to the determination of copper and cadmium in samples of saline produced formation water from petroleum exploration, and its accuracy was accessed by analyzing certified reference material CASS-5 (Nearshore Seawater Reference Material for Trace Metals) from National Research Council (Canada).

Abstract Precise replication of genetic material is essential to maintain genome stability. DNA replication is a tightly regulated process that ensues faithful copies of DNA molecules to daughter cells during each cell cycle. Perturbation of DNA replication may compromise the transmission of genetic information, leading to DNA damage, mutations, and chromosomal rearrangements. DNA replication stress, also referred to as DNA replicative stress, is defined as the slowing or stalling of replication fork progression during DNA synthesis as a result of different insults. Oncogene activation, one hallmark of cancer, is able to disturb numerous cellular processes, including DNA replication. In fact, extensive work has indicated that oncogene-induced replication stress is an important source of genomic instability in human carcinogenesis. In this review, we focus on main oncogenes that induce DNA replication stress, such as RAS, MYC, Cyclin E, MDM2, and BCL-2 among others, and the molecular mechanisms by which these oncogenes interfere with normal DNA replication and promote genomic instability.

An undergraduate organic chemistry experiment for oil extraction and biodiesel production using alternative biomass was developed, whereby oils of avocado, coconut and spent coffee grounds were obtained and submitted to transesterification reaction with CH3OH under NaOH catalysis. Avocado and coffee oils were obtained by typical extraction and coconut oil was obtained through water evaporation of coconut milk in a domestic microwave oven. The commercial oil of licuri (Syagrus coronate), a Brazilian native biomass, was also converted to biodiesel. All four oils and four biodiesels were characterized by 1H-NMR and FTIR, and a comparative study of these spectra reveled that FTIR analyses alone provides enough information to discriminate between oil and biodiesel and confirm transesterification reaction. Besides, the unsaturation degree of all oils was determined by 1H-NMR. A mechanistic proposal concerning the role of NaOH catalysis is presented, excluding the sodium methoxide formation.

Resumo Objetivo: Avaliação terapêutica da aplicação de bevacizumabe em pterígio recidivado com relação a acuidade visual, ceratometria, refração, sintomatologia. Métodos: O Grupo 1 (4 pacientes) recebeu 0,1ml de bevacizumabe (avastin) sendo avaliado posteriormente, nos dias 10 e 30 após a aplicação, buscando-se comparar com o exame previamente realizado, sendo o mesmo realizado com os outros dois grupos, em que o Grupo 2 (04 pacientes) recebeu 0,2ml de bevacizumabe e o grupo 3 (3 pacientes) recebeu 0,1 de injeção placebo. Resultados: Neste estudo foram avaliados 11 olhos de 11 pacientes. Dentre esses pacientes, 7 (63,6%) eram mulheres e 4 (36,4%) homens. Houve a variação na dioptria cilíndrica após o tratamento com dose de 0,1ml de bevacizumabe, durante a avaliação no trigésimo dia. Já o eixo cilíndrico teve uma modificação significativamente maior após a aplicação de 0,2ml. Em relação a variação dióptrica esférica, houve modificações nos três grupos. A ceratometria variou nos três grupos, principalmente no trigésimo dia de avaliação. Em relação a sintomatologia, observou-se uma redução na avaliação subjetiva da ardência, do prurido referida pelo paciente, e uma redução na avaliação biomicroscópica da hiperemia. Conclusão: Na aplicação do bevacizumabe no tratamento de pterígio recorrente, há modificação dos parâmetros esféricos e cilíndricos da refração, além da mudança ceratométrica e redução da sintomatologia.

Abstract Objective: Therapeutic evaluation of Bevacizumab application in relapsed pterygium concerning visual acuity, keratometry, refraction, symptomatology. Methods: Group 1 (4 patients) received 0.1 ml of Bevacizumab (avastin), being evaluated posteriorly on the tenth and thirtieth days after the application, seeking to compare with the exam previously made, being it realized with the other two groups, in which Group 2 (4 patients) received 0.2 ml of Bevacizumab and the Group 3 (3 patients) received 1 ml of the placebo injection. Results: In this study, eleven eyes of eleven patients were evaluated. Among these patients, 7 were women (63.6%) and 4 men (36.4%). There was a variation in the cylindrical diopter after the treatment with a dose of 0.1 ml of bevaciumab during the evaluation on the thirtieth day. Whereas the cylindrical shaft had a significantly larger modification after the application of 0.2 ml. Regarding the spherical diopter variation, there were modifications in the 3 groups. The keratometry varied in the 3 groups, mostly after the thirtieth day of evaluation. In relation to symptomatology, it was observed a reduction in the subjective evaluation of the eye burning sensation, the prurience mentioned by the patient and a reduction of the hyperemia biomicroscopy evaluation. Conclusion: In bevacizumab application in the recurrent pterygium treatment, there is modification of the spherical and cylindrical parameters of refraction, besides the changes in keratometry and the reduction of the symptomatology.

Resumo Objetivo: Avaliar o projeto Olhar Brasil sob um olhar crítico, examinando a prevalência dos pacientes encaminhados para consulta oftalmológica, pós-triagem, que realmente apresentem vícios de refração não corrigidos. Métodos: Revisão de prontuários entre Março de 2014 e Agosto de 2016, totalizando 339 pacientes entre 6 e 18 anos de idade, sendo 5 pré-escolares (2 - 6 anos e 11 meses), 124 escolares (2 - 6 anos e 11 meses) e 210 adolescentes (10-20 anos) entre os quais 156 do sexo masculino e 183 do feminino , em um hospital oftalmológico em Goiânia, Goiás, Brasil. Resultados: No total dos 339 pacientes examinados 143 (42,1 %) necessitaram de correção e 196 (57,8%) não. Entre os 156 pacientes do sexo masculino 74 (47,4%) apresentaram necessidade de uso de óculos contra 82 (52,5%) que não precisaram, em relação ao sexo feminino os números foram de 69 (37,7%) que tiveram alteração ao exame e 114 (62,2%) que não apresentaram alterações refrativas. Em relação a faixa etária, os adolescentes, escolares, e pré-escolares apresentaram em números absolutos e porcentagem respectivamente 102 (48,5%), 40 (32,2%) e 2 (40%) de indicação de lentes corretivas. Conclusão: O projeto Olhar Brasil tem importância relevante para sociedade em geral, com diminuição da evasão escolar, melhor rendimento escolar e consequentemente da qualidade de vida dos beneficiários, embora necessite melhor treinamento e aperfeiçoamento dos profissionais da Atenção Básica em Saúde, professores do ensino fundamental e os alfabetizadores que são responsáveis pela triagem.

Abstract Objective: Measure the “Projeto Olhar Brasil” under a critic point of view, examining the prevalence of patients referred for ophthalmological appointment, post-screening, that show refractive errors uncorrected. Methods: Review of records between March 2014 and August 2016, in totality of 339 patients between 6 and 18 years old, 5 preschools (2 - 6 years and 11 months) 124 school (7 - 9 years and 11 months) and 210 teenagers (10 - 20 years old). There were 156 males and 183 females, in an Ophthalmologic Hospital in Goiânia, Goiás, Brazil. Results: In total of 339 patients examined, 143 (42.1%) needed optical correction against 196 (57.8%) that not benefiting from the same. There were 74 (47.4%) males patients who required the use of eyeglasses, against 69 (37.7%) of females gender who obtained eyes test alterations. In relation to age, the teenagers, school and preschool showed in absolute numbers and percentage respectively 102 (48.5%), 40 (32.2%) and 2 (40%) indications of corrective lenses. Conclusion: The “Projeto Olhar Brasil” has great importance for society in general reducing the loss of students in school, improving school performance and consequently the quality of life of the beneficiaries, although it needs better training and improvement of professionals in primary health care, elementary school teachers and educators that are responsible for screening.

RESUMO Objetivo: Avaliar o aumento da prevalência de miopia entre pacientes atendidos em períodos diferentes em um serviço oftalmológico de Goiânia. Métodos: Foram comparados dados coletados em dois estudos científicos realizados em um serviço de oftalmologia, em diferentes períodos de tempo, que avaliaram dentre outros fatores, os erros refracionais dos participantes a partir destes dados comparou-se a porcentagem de pacientes portadores de miopia presentes nos estudos. Resultados: Observou-se um aumento na prevalência de Miopia dentre os participantes dos dois estudos. Na avaliação realizada entre 1995 e 2000 a porcentagem de pessoas com miopia representou 3,6% do total, já no estudo realizado no ano de 2014 a prevalência de pacientes com miopia foi de 9%. Dentre os pacientes com erros refracionais a prevalência de miopia no primeiro estudo foi de 9,97%, já no segundo a prevalência foi de 22%. Conclusão: Observou-se um aumento na prevalência de miopia entre os dois estudos, dados esses que corroboram com análises feitas que mostram um aumento da prevalência de miopia em todo mundo nos últimos 30 anos. Porém em uma proporção menor do que a observada em outros estudos populacionais.

ABSTRACT Objective: To evaluate the increased prevalence of myopia among patients in different periods in an ophthalmologic hospital in Goiânia. Methods: There were compared data collected in two scientific studies carried out in the same ophthalmologic hospital in different periods of time, they evaluated among other factors, the refractive errors of the participants, from this data there were compared the percentage of patients with myopia between the two studies. Results: There was an increase in the prevalence of myopia among the participants of the studies, in the evaluation carried out between 1995 and 2000 the percentage of people with myopia accounted for 3.6% of the total, in the study carried out in 2014 the prevalence of patients with myopia was 9%. Only among patients with refractive errors the prevalence of myopia in the first study was 9.97%, in the second study the prevalence was 22%. Conclusion: There was an increase in the prevalence of myopia between the two studies, these data corroborate with tests that shows an increasing prevalence of myopia in the world in the last 30 years. However, in a smaller proportion than in other population studies

RESUMO Objetivo: Avaliar a segurança e eficácia de três técnicas distintas para o tratamento de neoplasia intraepitelial córneo-conjuntival. Métodos: Vinte e seis pacientes, 11 mulheres e 15 homens, com idade entre 32 e 88 anos (média 64,84 anos), atendidos entre 1999 e 2014, foram incluídos neste estudo. Todos os pacientes foram submetidos à exérese da lesão com margem de segurança de 4mm e crioterapia a 2mm do limbo. Conforme o tratamento complementar, os pacientes foram divididos em três grupos: Grupo 1 (8 olhos): recobrimento conjuntival e 2 ciclos de mitomicina C 0,02% (MMC) 4x/dia por 10 dias, com intervalo de 30 dias entre os ciclos. Grupo 2 (9 olhos): recobrimento com membrana amniótica e 3 ciclos de MMC 3x/dia por 10 dias, com intervalo de 10 dias entre o 1º e o 2º ciclo e 30 dias entre 2º e o 3º ciclo. Grupo 3 (9 olhos): recobrimento com membrana amniótica sem o uso de MMC. O acompanhamento dos pacientes variou de 3 meses a 14 anos (média: 4 anos). Resultados: Vinte e três pacientes apresentaram erradicação da lesão com um único tratamento. Três pacientes do Grupo 3 apresentaram recidiva da lesão após 3 meses, 6 meses e 1 ano do tratamento. Dois deles foram retratados pela técnica 1, sem nova recidiva após seguimento de 3 e 4 anos; o outro paciente foi submetido à enucleação. Não foram observados efeitos colaterais relacionados ao uso da mitomicina C durante o seguimento. Conclusão: Após exérese da lesão e crioterapia, os pacientes tratados com recobrimento conjuntival ou membrana amniótica associado à mitomicina C mostraram tendência a resultados mais eficazes.

ABSTRACT Purpose: To evaluate the safety and efficacy of three different techniques for the treatment of conjunctival-corneal intraepithelial neoplasia. Methods: Twenty-six eyes of 26 patients, 11 women and 15 men were included in a nonrandomized, retrospective, observational case series. Mean patient age was 64 years (range, 32-88 years).All patients were treated from 1999 to 2014. Mean postoperative follow-up was 4 years (range, 3 months to 14 years). All patients underwent excision of the lesion with a 4-mm safety margin and a 2-mm from the limbus cryotherapy. As further treatment the patients were divided into three groups: Group 1 (8 eyes): conjunctival autograft and 2 cycles of mitomycin C 0.02% (MMC) eye drops, four times daily for 10 days with an interval of 30 days between cycles. Group 2 (9 eyes): amniotic membrane (AM) graft and 3 cycles of MMC eye drops, three times daily for 10 days with an interval of 10 days between the 1st and 2nd cycle and 30 days between the 2nd and 3rd cycle. Group 3 (9 eyes): AM graft without MMC eye drops. Results: After a single treatment, the lesions were eradicated in twenty-three patients. Recurrence was noted in three patients from Group 3 at 3 months, 6 months and 1 year after treatment. Two of them were retreated by the technique used in Group 1 without further recurrence; the other patient underwent enucleation. No adverse effects related to the use of mitomycin C were observed during. There were no side effects related to the use of mitomycin C during follow-up. Conclusion: After surgical excision and cryotherapy, patients treated with conjunctival or amniotic membrane graft associated with mitomycin C, showed a tendency to more effective results.

A petrochemical effluent is usually a matrix of very high complexity and composition variability, requiring robust and suitable methods for routine analysis. In this paper, the feasibility of applying a voltammetric technique for the determination of metals species in the petrochemical industry effluent was demonstrated after UV-assisted digestion procedure. Voltammetric (electrolyte volume, deposit time, pulse time, pulse amplitude and scan rate) and digestion variables (hydrogen peroxide volume, nitric acid volume and digestion time) were studied using a 2-level factorial design. The developed voltammetric method using anodic stripping voltammetry (ASV) presented limits of quantification of 11, 5, 15 and 5 µg L−1 for Zn, Cd, Pb and Cu, respectively, and was effective to analyze petrochemical effluents after UV-digestion.

RESUMO Objetivo: analisar a prevalência das uveítes em pacientes atendidos em um serviço oftalmológico terciário em Teresina, Piauí. Métodos: estudo retrospectivo baseado em prontuários de pacientes atendidos nesse serviço. Foram descritos: gênero, faixa etária, procedência, doença de base, diagnóstico anatômico, aspecto clínico e tempo de evolução. Resultados: foram incluídos 403 prontuários constatando-se que a cada 1000 pacientes atendidos neste serviço, 3,2 tinham uveíte.A idade média dos pacientes foi de 42 anos, tanto o gênero feminino (50,6%) quanto o gênero masculino (49,4%) foram acometidos similarmente, com 61,5% dos pacientes provenientes da capital. A doença de base mais frequente foi a toxoplasmose, seguida das uveítes idiopáticas apenas com manifestações oculares. Quanto à classificação anatômica, 49,6% foram posteriores e 3,5% foram intermediárias. Em relação ao aspecto clínico, 64% foram granulomatosas, 24,8% não-granulomatosas e 11,2% não foram classificáveis. Segundo a evolução clínica, 41,4% foram agudas, seguidas de 30,8% crônicas, 14,4% recorrentes e em 13,4% os pacientes não foi feito o acompanhamento. Conclusão: pudemos constatar que para cada 1000 pacientes atendidos neste serviço 3,2 tinham uveíte, apresentando-se a toxoplasmose como importante fonte de uveíte neste serviço.

ABSTRACT Objective: To analyze the prevalence of uveitis in patients treated at a tertiary ophthalmic service in Teresina, Piauí State, Brazil. Methods: This was a retrospective study based on medical records of patients treated at this service. Sex, age, origin, underlying diseases, anatomical diagnosis, clinical aspects and progression time were described. Results: 403 records were included, noting that 3.2 out of every 1,000 patients treated at the service had uveitis.The average age of patients was 42 years old, with both sexes (50.6% females and 49.4% males) affected similarly, and with 61.5% coming from the state capital, Teresina. The most common underlying disease was toxoplasmosis, followed by idiopathic uveitis with ocular manifestations only. As to the anatomical classification, 49.6% of them were posterior and only 3.5% were intermediate. Regarding the clinical aspects, 64% were granulomatous, 24.8% non-granulomatous, and 11.2% were not classifiable. According to the clinical progression, 41.4% were acute, followed by 30.8% chronic, 14.4% recurrent cases, and 13.4% of patients did not return for medical care. Conclusion: we found that for every 1,000 patients treated at the service, 3.2 had uveitis, with toxoplasmosis itself found to be an important source of uveitis.

RESUMO Objetivo: Determinar a segurança e eficácia do cross-linking corneano (CXL) em pacientes de 9 a 14 anos de idade com ceratocone progressivo. Métodos: Dezesseis olhos de onze pacientes (8 homens e 3 mulheres) com ceratocone progressivo foram submetidos ao CXL, de acordo com o protocolo padrão de Dresden. A média do tempo de seguimento foi de 26 meses (variando de 12 a 60 meses). Os exames pré e pós-operatórios incluíram: acuidade visual sem correção (AVSC), melhor acuidade visual com correção (AVCC), topografia corneana, tonometria, refração, paquimetria corneana, e contagem de células endoteliais. Resultados: Na última visita de acompanhamento ambulatorial, a AVCC melhorou pelo menos uma linha na tabela de Snellen em 6 olhos (37,5%) e permaneceu estável em 9 olhos (56,25%). Dois olhos (12,5%) de pacientes que coçam os olhos com frequência, exigiram retratamento devido à progressão do ceratocone, 15 e 28 meses após o primeiro CXL. A refração e contagem de células endoteliais mantiveram-se estáveis. Os resultados topográficos mostraram melhora estatisticamente significativa nos valores do K máximo até dois anos após o CXL. No entanto, houve perda de significância ao longo do tempo. Nenhuma complicação peroperatória foi observada. Dois olhos (12,5%) apresentaram haze grau I, que regrediu após um mês de terapia com esteróide tópico. Conclusão: Neste estudo com pacientes selecionados, de 9 a 14 anos de idade, o CXL mostrou ser uma opção segura e eficaz para o tratamento do ceratocone progressivo. No entanto, o efeito pode não ser duradouro, podendo ser necessário um novo tratamento. Maior amostragem e maior seguimento são necessários para verificar esta tendência.

ABSTRACT Purpose: To determine the safety and efficacy of corneal collagen cross-linking (CXL) for progressive keratoconus in patients aged between 9 and 14 years old. Methods: Sixteen eyes of 11 patients (8 male and 3 female) with progressive keratoconus underwent epithelium-off CXL according to the standard Dresden protocol. Mean follow-up was 26 months (range, 12 to 60 months). Pre- and postoperative examinations included: uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), corneal topography, tonometry, refraction, corneal pachymetry, and endothelium cell count. Results: At the last follow-up visit, BSCVA improved by at least one Snellen line in six eyes (37.5%) and remained stable in nine eyes (56.25%). Two eyes (12.5%) in habitual eye rubbers required a re-treatment due to keratoconus progression, at 15 and 28 months after first CXL. Manifest refraction and endothelium cell count remained stable. Topographic results showed statistically significant improvement in maximum K readings up to two years after CXL. However, this lost significance over time. No intraoperative complications were observed. Two eyes (12.5%) presented grade one haze, which regressed after a month of topical steroid therapy. Conclusion: In this study of selected patients aged 9 to 14, CXL was a safe and effective option for the treatment of progressive keratoconus. However, the effect in stemming the disease may not be long lasting and may require retreatment. A larger sample size and longer follow-up time are needed to verify this trend.