Long-term performance: strength and metal encapsulation in alkali-activated iron ore tailings.

Understanding the strength behavior and leaching characteristics of mining tailings stabilized with alkali-activated cements in the short, medium, and long term is crucial for the feasibility of material applications. In this context, this study assessed the stabilization/solidification of iron ore tailings (IOT) using alkali-activated binder (AAB) composed of sugarcane bagasse ash and eggshell lime at curing times of 7, 28, 60, 90, 180, and 365 days. Additionally, leaching tests were conducted, along with the examination of possible changes in the chemical and mineralogical composition resulting from exposure to acidic environments. Tests included unconfined compression strength (UCS), leaching, X-ray diffraction, and Fourier-transform infrared spectroscopy for the IOT-AAB mixtures. The highest increase in UCS was observed between 7 and 60 days, reaching 6.47 MPa, with minimal variation thereafter. The AAB-bonded IOT exhibited no metal toxicity over time. Elements Ba, Mn, Pb, and Zn present in IOT and ash were encapsulated in the cemented matrix, with complete encapsulation of all metals observed from 90 days of curing time. The mineralogy of the stabilized/solidified tailings showed no changes resulting from leaching tests. Characteristic bands associated with the presence of N-A-S-H gel were identified in both pre-leaching and post-leaching samples for all curing times analyzed. Exposure to acidic environments altered bands related to carbonate bonds formed in the IOT-AAB mixture.

FACTORS ASSOCIATED WITH A HIGHER NUMBER OF ESOPHAGEAL DILATIONS IN CHILDREN WITH A HISTORY OF ALKALINE INGESTION.

BACKGROUND: Children who experience alkaline injury are at risk for the development of esophageal strictures and the need for esophageal dilations. OBJECTIVE: We aimed to assess predictors for a higher number of esophageal dilatations in children following alkali ingestion. METHODS: Single-center retrospective cohort study including children who underwent esophagogastroduodenoscopy (EGD) after alkali ingestion. Possible predictive factors for the need for esophageal dilatations were evaluated. RESULTS: A total of 34 patients were included, and 19 were female (55.9%). The median age at the time of the accidents was 20.6 months (IQR 15-30.7). All alkali ingestions were accidental, in all cases involving liquid products, and most (24/34; 70%) occurred at the child's home. Homemade liquid soap was the agent in half of the cases. The most frequently reported symptom at presentation was vomiting (22/34, 64.7%). The median follow-up time was 3.2 years (IQR 1.1-7.4). On follow-up, the median number of esophageal dilatations required for these patients was 12.5 (IQR 0-34). Among demographic factors, male gender (P=0.04), ingestion of homemade products (P<0.01), and accidents happening outside of the household environment (P=0.02) were associated with a greater number of esophageal dilations on follow-up. An endoscopic classification Zargar of 2B or higher (P=0.03), the presence of stricture at the time of the second EGD (P=0.01), and gastroesophageal reflux disease (GERD) as a late complication (P=0.01) were also associated with a greater number of esophageal dilations on long term follow-up. CONCLUSION: Beyond the endoscopic classification severity - a well-known risk factor for the strictures after alkali ingestions, we found that male gender, accidents with homemade products, and accidents occurring outside the household environment were significantly associated with a greater number of esophageal dilatations in the long-term follow-up of children following alkali ingestion.

Environmental, economic, and social impacts of sugar cane bagasse and eggshell wastes for soil stabilization.

Sustainability is a core topic for all sectors including geotechnical engineering (e.g., design of foundations, earthworks structures, and pavements for major infrastructure and building projects). Despite being comprised of environmental, economic, and social pillars, most sustainability studies in this area have focused on the first. Furthermore, social impacts and the three pillars integration are little explored. As a result, there is a lack of systemic and holistic assessments of innovative geotechnical alternatives. This research advances in this area by performing a complete sustainability assessment and integration of the environmental, economic, and social pillars of two expansive soil stabilization alternatives: (i) sugar cane bagasse ash combined with hydrated eggshell lime alkali-activated by sodium hydroxide (NaOH) and (ii) Portland cement. Individual analyses were carried out to determine the environmental, economic, and social impacts, and the single sustainability index. Alkali-activated binder dosages showed higher impacts in 4 out of 10 environmental categories. For both binders, high-density/low-binder dosages contributed to environmental and economic sustainability as they require lower quantities of raw materials and diesel for materials transportation. The total costs of alkali-activated binder dosages ($189.79 and $154.45) were higher than that of Portland cement ($72.49 and $54.04), mainly due to the high cost of NaOH acquisition. However, the alkali-activated binder dosages implied lower carbon dioxide (CO2) emissions and thus lower social cost of CO2. The alternative binder presented a higher positive social impact. The alkali-activated high-density/low binder dosage is the most sustainable soil stabilization strategy.

Purification and characterization of an alkali-organic solvent-stable laccase with dye decolorization capacity from newly isolated Lysinibacillus fusiformis W11.

A new Lysinibacillus fusiformis strain with abundant laccase activity was isolated from soil under forest rotted leaf and identified as L. fusiformis W11 based on its 16S rRNA gene sequence and physiological characteristics. The laccase LfuLac was purified and characterized. The optimum temperature and pH of LfuLac on guaiacol were 45 °C and pH 9, respectively. LfuLac kept 78%, 88%, 92%, 74%, and 47% of activity at pH 7-11, respectively, suggesting the alkali resistance of the enzyme. The effects of various metal ions on LfuLac showed that Cu2+, Mg2+, and Na+ were beneficial to laccase activity and 10 mM Cu2+ increased the activity of LfuLac to 216%. LfuLac showed about 90% activity at 5% organic solvents and more than 60% activity at 20%, indicating its resistance to organic solvents. In addition, LfuLac decolorized different kinds of dyes. This study enriched our knowledge about laccase from L. fusiformis W11 and its potential industrial applications.

Enzymatic production of xylooligosaccharides from corn cobs: Assessment of two different pretreatment strategies.

Corn cobs (CCs) are abundant xylan-rich agricultural wastes. Here, we compared CCs XOS yields obtained via two different pretreatment routs, alkali and hydrothermal, using a set of recombinant endo- and exo-acting enzymes from GH10 and GH11 families, which have different restrictions for xylan substitutions. Furthermore, impacts of the pretreatments on chemical composition and physical structure of the CCs samples were evaluated. We demonstrated that alkali pretreatment route rendered 59 mg of XOS per gram of initial biomass, while an overall XOS yield of 115 mg/g was achieved via hydrothermal pretreatment using a combination of GH10 and GH11 enzymes. These results hold a promise of ecologically sustainable enzymatic valorization of CCs via "green" and sustainable XOS production.

Atividade de alcaloides inibidores da acetilcolinesterase no tratamento da doença de Alzheimer: uma revisão sistemática / Activity of Acetylcholinesterase inhibitor Alkaloids in the treatment of Alzheimer's Disease: a systematic review

Objetivo: descrever a atividade de inibição da enzima acetilcolinesterase (AChE), por meio de ativos extraídos de alcaloides naturais. Metodologia: este estudo se configura como uma revisão sistemática da literatura, no período de janeiro de 2015 a setembro de 2021, nas bases de dados PUBMED, LILACS e SCIENCE DIRECT, com os descritores Acetylcholinesterase; Alzheimer; Alkaloids. As informações obtidas foram tabuladas para avaliação dos alcaloides inibidores da acetilcolinesterase. Resultados: de 563 artigos encontrados, 17 foram utilizados. Dois deles relataram a atividade de alcaloides inibidores da AChE por meio de ensaios clínicos, enquanto os demais a realizaram por testes in vitro. De 160 substâncias estudadas, 48 apresentaram atividade anticolinesterásica, as quais foram avaliadas de acordo com a sua concentração inibitória média (IC50). Discussão: a eficiência dos alcaloides como inibidores da AChE, provavelmente está relacionada com sua carga positiva no pH do organismo e sua boa biodisponibilidade, tendo como consequência uma atividade duradoura in vivo, em comparação com os medicamentos sintéticos. Conclusão: no presente estudo, foi possível observar uma grande diversidade de substâncias alcalóidicas antiAChE. Contudo, torna-se necessária a realização de mais ensaios in vivo e in vitro para a constatação efetiva da atividade dessas moléculas.

Objective: describe the activity of the enzyme Acetylcholinesterase (AChE) through natural actives extracted from alkaloids. Methodology: this study is a systematic literature review, from January 2015 to September 2021, in the PUBMED, LILACS, and SCIENCE DIRECT databases, with the descriptors Acetylcholinesterase; Alzheimer's; Alkaloids. The information obtained was tabulated for the evaluation of Acetylcholinesterase inhibitor alkaloids. Results: of 563 articles found, 17 were used. Two of them reported the activity of AChE-inhibiting Alkaloids through clinical trials, while the others performed it through in vitro tests. Of 160 substances studied, 48 showed anticholinesterase activity, which was evaluated according to their mean inhibitory concentration (IC50). Discussion: the efficiency of Alkaloids as AChE inhibitors is probably related to their positive charge on the body's pH and their good bioavailability, resulting in a long-lasting activity in vivo compared to synthetic drugs. Conclusion: in the present study, it was possible to observe a great diversity of antiAChE alkaloid substances. However, it is necessary to carry out more in vivo and in vitro tests to verify the effective activity of these molecules.

A relação do transtorno do espectro autista e a disbiose intestinal: uma revisão integrativa / The relationship between autism spectrum disorder and intestinal dysbiosis: an integrative review

Objetivos: evidenciar as relações e a existência do agravamento do Transtorno do Espectro Autista devido à disbiose intestinal. Métodos: revisão integrativa realizada segundo a pergunta norteadora: Existe comprovação científica entre a relação do TEA e disbiose intestinal que favoreça a melhora na prática clínica e indicações de possíveis respostas? Buscou-se por artigos publicados entre janeiro de 2016 e janeiro de 2021, nas bases de dados: PubMed, SciELO, LILACS, GOOGLE ACADÊMICO. Foram utilizados os descritores (DeCS): "Transtorno do Espectro Autista"; "Microbiota gastrointestinal"; "Disbiose", associados pelo operador booleano "E". Foram incluidos artigos de revisões bibliográficas, completos, originais, limitados aos idiomas inglês e português brasileiro, publicados nos últimos cinco anos, e que, após leitura do resumo, estivessem dentro do escopo da revisão. Resultados: Foram identificados 52 manuscritos e, após aplicação dos critérios de inclusão e exclusão, foram considerados 11 artigos que evidenciam o agravamento do TEA por fatores intrínsecos à microbiota intestinal. Conclusão: existe importante influência causal do eixo bidirecional cérebro-intestino-microbiota na etiologia e exacerbaçao das manifestações clínicas do Transtorno do Espectro Autista devido à disbiose intestinal e aos fatores gastrointestinais de origem idiopática.

Objectives: to highlight the relationships and the existence of Autistic Spectrum Disorder aggravation due to intestinal dysbiosis. Methods: integrative review conducted according to the guiding question: Is there scientific evidence of the relationship between ASD and intestinal dysbiosis that favors improvement in clinical practice and indications of possible answers? We searched for articles published between January 2016 and January 2021 in databases: PubMed, SciELO, LILACS, and GOOGLE ACADEMIC. The following descriptors (DeCS) were used: "Autistic Spectrum Disorder"; "Gastrointestinal microbiota"; "Dysbiosis", associated with the Boolean operator "AND". We included literature review articles, complete, original, limited to English and Brazilian Portuguese languages, published in the last five years, and which, after reading the abstract, were within the scope of the review. Results: 52 manuscripts were identified, and after applying the inclusion and exclusion criteria, 11 articles were considered that show the worsening of ASD due to factors intrinsic to the intestinal microbiota. Conclusion: there is an important causal influence of the bidirectional brain-gut-microbiota axis in the etiology and exacerbation of clinical manifestations of Autism Spectrum Disorder due to intestinal dysbiosis and gastrointestinal factors of idiopathic origin.

Mining tailings and alkali activation: a comprehensive bibliometric review.

Significant amounts of mining tailings are generated and disposed of every year in dams, leading to potentially serious environmental and safety problems. To identify alternatives for the disposal of these wastes, research works involving their potential application as precursors in the development of alkaline-activated materials have been published in recent years. In this context, the objective of this paper is to present an overview of the main contributions already made on the subject, identified through a bibliometric review and content analysis in the Scopus and Web of Science databases. There was an exponential growth of interest in the subject in the period 2019-2021, when more than 50% of the papers were published. The most used tailings and sub-areas of research were also identified.

Discovery of New Phenylacetone Monooxygenase Variants for the Development of Substituted Indigoids through Biocatalysis.

Indigoids are natural pigments obtained from plants by ancient cultures. Romans used them mainly as dyes, whereas Asian cultures applied these compounds as treatment agents for several diseases. In the modern era, the chemical industry has made it possible to identify and develop synthetic routes to obtain them from petroleum derivatives. However, these processes require high temperatures and pressures and large amounts of solvents, acids, and alkali agents. Thus, enzyme engineering and the development of bacteria as whole-cell biocatalysts emerges as a promising green alternative to avoid the use of these hazardous materials and consequently prevent toxic waste generation. In this research, we obtained two novel variants of phenylacetone monooxygenase (PAMO) by iterative saturation mutagenesis. Heterologous expression of these two enzymes, called PAMOHPCD and PAMOHPED, in E. coli was serendipitously found to produce indigoids. These interesting results encourage us to characterize the thermal stability and enzyme kinetics of these new variants and to evaluate indigo and indirubin production in a whole-cell system by HPLC. The highest yields were obtained with PAMOHPCD supplemented with L-tryptophan, producing ~3000 mg/L indigo and ~130.0 mg/L indirubin. Additionally, both enzymes could oxidize and produce several indigo derivatives from substituted indoles, with PAMOHPCD being able to produce the well-known Tyrian purple. Our results indicate that the PAMO variants described herein have potential application in the textile, pharmaceutics, and semiconductors industries, prompting the use of environmentally friendly strategies to obtain a diverse variety of indigoids.

Mercury methylation upon coastal sediment resuspension: a worst-case approach under dark conditions.

Mercury behavior upon resuspension of sediments from two impacted areas of Guanabara Bay was evaluated to assess worst-case methylmercury (MeHg) responses, under dark experimental conditions to prevent demethylation by photolysis. Study areas include the Rio de Janeiro Harbor (RJH) and the chlor-alkali plant-affected Meriti River (MR) estuary. Total mercury (THg) and MeHg concentrations were determined along 24-h experiments of sediment resuspension in the bay water in dark conditions. Fine-grained Meriti River (MR) estuary sediments had 8 times higher MeHg initial concentrations than sandy Rio de Janeiro Harbor (RJH) sediments (3.4 ± 0.29 vs. 0.41 ± 0.1 ng g-1, respectively). Though THg contents were uncorrelated with resuspension time, statistically significant correlations of MeHg (rs = 0.78) and %MeHg in relation to THg (rs = 0.86) with resuspension time were observed for RJH sediments, indicating net methylation only for this study site. These positive correlation trends correspond to a 2.8 times MeHg concentration increase (ΔMeHg = 0.75 ng g-1) and 4.4 times increase in %MeHg (Δ%MeHg = 1.0%), after 24 h of resuspension. This suggests that assessments of factors affecting the MeHg spatial-temporal variability and associated toxicity risks can be limited in some sites if concentration changes due to sediment resuspension-redeposition processes are not considered. Therefore, the inclusion of MeHg evaluation before and after sediment resuspension events is recommendable for the improvement of dredging licensing and monitoring activities.

Historical mercury contamination in a major Latin American industrial and port complex: The case of the Santos estuary, Southeastern Brazil.

The present study determined total mercury (Hg) in four 210Pb dated sediment cores to assess the historical anthropogenic Hg accumulation in the Santos estuary, Southeastern Brazil. Background levels were identified using the deepest sections of the cores, corresponding to pre-industrial ages. Mercury distribution in the sediment cores (0.02-2.64 mg kg-1) presented a large spatial and temporal variation. Contamination is highest in the upper estuary and indicates that the industrial hub, especially a chlor-alkali plant is the primary source of Hg. A contaminant trap effect is observed in this area associated with high fine sediment accumulation and Hg fluxes. The contamination pattern indicates that the regions not affected by direct inputs are influenced by reworking, resuspension, and transport of contaminated sediments by tidal flows. The Hg enrichment in the upper layers of the sediment cores demonstrates that the environmental actions fulfilled in the 1980s were insufficient to control Hg pollution in the Santos estuary.

Titanium Powder 3D-Printing Technology for a Novel Keratoprosthesis in Alkali-Burned Rabbits.

Purpose: To evaluate the surgical technique, clinical performance, and biocompatibility of a novel keratoprosthesis (KPro) named KPro of Brazil (KoBra) in an alkali-burned rabbit model. Methods: Two-piece three-dimensional-printed titanium powder and polymethyl methacrylate KPros were implanted into 14 alkali-burned corneas of 14 rabbits using an autologous full-thickness corneal graft as the KPro carrier. Rabbits were examined weekly for 12 months to evaluate retention and postoperative complications. Anterior segment optical coherence tomography (AS-OCT) and scanning electron microscopy (SEM) were performed at the end of the experiment to evaluate the relationship between the KoBra and the carrier graft. Results: All surgeries were performed without intraoperative complications, and the immediate postoperative period was uneventful. In 12 eyes (85.7%), the implanted KPros integrated into the operated eyes and maintained clear optics without extrusion or further complications over 12 months. Two eyes presented late postoperative complications that progressed to KPro extrusion: one had a presumed infectious keratitis, and the other had sterile stromal necrosis. AS-OCT demonstrated the correct relationship of the device and carrier graft in all remaining animals at the final follow-up. SEM findings indicate the integration of the porous structure of the back plate into the surrounding tissue. Conclusions: Clinical evaluations, AS-OCT, and SEM findings indicate good biointegr-ation of the implanted device into the corneal carrier graft. KoBra has the advantage of using recipients' own corneas as the prosthesis supporter, and its surgical procedure is relatively simple and safe. Translational Relevance: Titanium three-dimensional-printed technology used in an animal limbal stem-cell deficiency model holds great promise for the treatment of corneal blindness in humans.

Effects of the amendment with almond shell, bio-waste and almond shell-based biochar on the quality of saline-alkali soils.

This study aimed to evaluate the effect of the amendment with almond shell bio-waste (AS) and almond shell-based biochar (ASB), in different mass ratios (5, 10, and 15%), on the physicochemical properties of three different saline soils, using the growth of arugula seedlings as a bioindicator of the enhancement achieved. Data were analyzed based on a completely randomized design in a factorial arrangement with four replications. The results showed that the low-salinity soil (T1) presented the best physicochemical characteristics and growth parameters. The addition of AS and ASB in low proportions to the saline soils reduced the pH and electrical conductivity values. An increase in the amendment proportion led to an increase in these variables. Moisture, organic matter, and organic carbon increased, and the cation exchange capacity decreased, generating positive effects on soil quality. The values of exchangeable sodium percentage (ESP) showed that T3 presented the highest sodicity, followed by T2 and T1. The treatment with 5% ASB produced better results regarding total plant length, fresh and dry weights, leaf area, and leaf chlorophyll content. Finally, linear regression models were applied to describe the dependence of the agronomic variables on the ratio of biochar added.

Leaching assessment of cemented bauxite tailings through wetting and drying cycles of durability test.

Disposal of mine tailings can cause negative environmental effects by releasing contaminants to surface and underground water. Alkali activation is a promising technique for immobilizing metals in stabilization/solidification of these wastes. This study evaluates the leaching behavior of cemented bauxite tailings (BT) submitted to weathering conditions. The alkali-activated binder was composed of sugar cane bagasse ash, carbide lime, and sodium hydroxide solution. Comparisons of the durability and leaching behavior of BT stabilized with alkali-activated binder and high initial strength Portland cement were performed. The durability results for alkali-activated were similar to the Portland cement, showing an average difference of 16%. Portland cement showed favorable results in the encapsulation of heavy metals like Cd and Hg, while the alkali-activated cement on Al, Cr, and Se. For Ba, Fe, Mn, and Zn immobilization, both types of cement presented an equal performance. The durability and leaching behavior of stabilized bauxite tailings is governed by the cement content and porosity of the blends, as well as their pH.

Introdução dos alimentos no primeiro ano de vida e prevenção da alergia alimentar: quais as evidências? / Introduction of food in the first year of life and food allergy prevention: what is the evidence?

Objetivo: A incidência das doenças alérgicas cresceu nas últimas décadas. Na tentativa de conter o aumento da alergia alimentar (AA) ao longo dos anos, estratégias de prevenção vêm sendo implementadas. Para promover um melhor entendimento dos dilemas que permeiam a introdução alimentar no primeiro ano de vida, esse artigo trata de uma revisão bibliográfica narrativa sobre a introdução dos alimentos complementares no primeiro ano de vida e possíveis associações com a prevenção primária da alergia alimentar. Fonte dos dados: Publicações relevantes foram pesquisadas nas bases de dados Cochrane Library, MEDLINE, PubMed, Guidelines International Network, National Guidelines Clearinghouse e revisadas recomendações do guia e do consenso nacional de alergia alimentar. Resultados: Estudos observacionais diversos e ensaios clínicos randomizados estão disponíveis, bem como recomendações publicadas por organizações científicas; no entanto, de qualidade variável. Foram consideradas as recomendações de diretrizes de prática clínica classificadas como de alta qualidade e publicações recentes ainda não categorizadas de forma sistemática em sua qualidade, mas internacionalmente reconhecidas como relevantes para a atenção primária. Conclusão: Até o momento, não há evidências consistentes de que a introdução precoce, antes dos 6 meses, dos alimentos alergênicos, contribua para a prevenção de alergia a alimentos na população geral.

Objective: The incidence of allergic diseases has increased in recent decades. In an attempt to contain the increase in food allergy (AA) over the years, prevention strategies have been implemented. To promote a better understanding of the dilemmas that permeate the introduction of food in the first year of life, this article deals with a narrative literature review on the introduction of complementary foods in the first year of life and possible associations with the primary prevention of food allergy. Data source: Relevant publications were searched in the Cochrane Library, MEDLINE, PubMed, Guidelines International Network, National Guidelines Clearinghouse, and revised recommendations from the national food allergy guide and consensus. Results: Several observational studies and randomized controlled trials are available, as well as recommendations. published by scientific organizations; however, of variable quality. Recommendations from clinical practice guidelines classified as high quality and recent publications not yet systematically categorized in their quality, but internationally recognized as relevant to primary care, were considered. Conclusion: To date, there is no consistent evidence that the early introduction, before 6 months, of allergenic foods contributes to the prevention of food allergy in the general population.

Effect of Non-Calcined Sugarcane Bagasse Ash as an Alternative Precursor on the Properties of Alkali-Activated Pastes.

BFS-MK-based alkali-activated materials are well established as an alternative for sustainable and green construction. This work aims to collaborate and encourage the use of biomass ashes, such as sugarcane bagasse ash (SCBA), as a precursor in alkali-activated materials (AAM). This ash is a rich source of aluminosilicate, which is a primary requirement for this application. In addition, this waste is still an environmental liability, especially in developing countries, and with a large volume of annual production. Thus, in this research, alkali-activated pastes (AA) were produced using sugarcane bagasse ash (SCBA), granulated blast furnace slag (BFS) and metakaolin (MK) as precursors. In addition, environmental gains were encouraged with energy savings, with no extra reburn or calcination steps in the SCBA. Thus, the precursors were characterized by laser granulometry, X-ray fluorescence spectrometry (XRF), X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The pastes were produced by mixing the precursors with the activator, composed of a mixture of sodium hydroxide 8 mol/L and sodium silicate. Aiming to study the incorporation of SCBA, all samples have a precursor/activator ratio and a BFS/(BFS + MK) ratio constant of 0.6. The compressive strength analysis, FTIR, XRD, TGA, SEM and isothermal calorimetry analyses pointed out the occurrence of alkaline activation in all proposed samples for curing times of 7, 28 and 91 days. The sample GM0.6-BA0 (15% SCBA) achieved the highest compressive strength among the samples proposed (117.7 MPa, at 91 days), along with a good development of strength throughout the curing days. Thus, this work presents the properties of alkaline-activated pastes using SCBA as a sustainable and alternative precursor, seeking to encourage the use of raw materials and alternative waste in civil construction.

Changes in the structure and composition of pineapple leaf fiber after alkali and ionic surfactant pretreatments and their impact on enzymatic hydrolysis.

The current study investigated the effects of two different pretreatments (NaOH and alkaline surfactant assisted) on the chemical, morphological and enzymatic saccharification of pineapple leaf fiber (PALF). Results showed that both pretreatments significantly reduced lignin content of the biomass, achieving a 69.6 and a 76.3% reduction for NaOH and surfactant pretreated materials, respectively. SEM, CLSM and FTIR-ATR techniques were used to evaluate morphological changes in the fibers after pretreatments. Images obtained revealed cellulose exposure and lignin redistribution in the pretreated fibers. Surfactant pretreated material provided the best results after enzymatic hydrolysis compared to NaOH and untreated PALF. A final enzymatic hydrolysis yield of 81.8% was obtained after a 24 h process using surfactant pretreated fibers, in comparison to 75.9 and 45.1% yields for NaOH pretreated material and raw fibers, respectively. Nowadays, the use of agricultural residues for high added value products is of great importance for sustainable development. This work specifically studied an effective and green approach for lignin removal and enzymatic hydrolysis from pineapple leaf fiber that is an abundant waste in Costa Rica and an interesting feedstock for biorefinery processes design.

Gender Dysphoria Publication Trends: A Bibliometric Analysis between 1900 and 2018 / Tendencias de publicación sobre disforia de género: Un análisis bibliométrico entre 1900 y 2018

Objective Research on gender dysphoria (GD) has been growing over the last decades with increasing interest in understanding and characterizing the causal relationships between psychological, genetics, hormonal, and sociocultural factors. Changes and acceptance of this condition as non-pathologic have led to significant changes in general perspective and its management over time. Our objective is to carry out a bibliometric analysis to know the publication trends and quality of evidence related to gender dysphoria. Methods A systematic search and critical review of the literature was carried out between January 1900 and December 2018 to perform a bibliometric analysis. Research was done in the following databases: OVID, PubMed, EMBASE, Scopus, Web of Science and Google Scholar. The medical subject headings (MeSh) terms used were: gender dysphoria; and surgery and psychology. The results were plotted using the VOSviewer version 1.6.8. Statistical analyses were performed with the IBM SPSS, Version 25.0. Results A total of 1,239 manuscripts were identified, out of which 1,041 were selected. The average number of cited times per year per manuscript is 1.84 (interquartile range [IQR] 0-2.33). The average impact index was 47.8 (IQR 20-111.6). The median of total citations per manuscript was 3 (IQR 0-33.1), and the highest number of citations per manuscript was 484. Most publications focus on the psychological aspects of GD, and there is a significant amount of manuscripts related to social and anthropological issues. Most articles have a low level of scientific evidence. Conclusion There is a great amount of published literature on GD; however, there is a significant level of disagreement in many respects on this topic. Regarding surgical gender-affirmation, there is a lack of information supported by high level of evidence to uphold the emerging expansion of medical practices.

Objetivo La investigación sobre la disforia de género (DG) ha crecido en las últimas décadas con un interés creciente por comprender y caracterizar las relaciones causales entre factores psicológicos, genéticos, hormonales y socioculturales. La aceptación de esta condición como no patológica ha llevado a cambios significativos en la perspectiva general y su manejo a lo largo del tiempo. Nuestro objetivo es realizar un análisis bibliométrico para evaluar las tendencias de publicación y la calidad de evidencias relacionadas con la disforia de género. Métodos Se realizó una búsqueda sistemática y revisión crítica de la literatura entre enero de 1900 y diciembre de 2018 para hacer un análisis bibliométrico. Se utilizaron los criterios de los Ítems de Informe Preferido para Revisiones Sistemáticas y Metaanálisis (Preferred Reporting Items for Systematic Reviews and Meta-analysis, PRISMA, en inglés), y la investigación se realizó en las siguientes bases de datos: OVID, PubMed, EMBASE, Scopus, Web of Science y Google Scholar. Los términos de encabezados de temas médicos (medical subject headings, MeSh, en inglés) utilizados fueron: disforia de género; y cirugía y psicología. Los resultados se trazaron utilizando VOSviewer, versión 1.6.8. Los análisis estadísticos se realizaron con el IBM SPSS, versión 25.0. Resultados Se identificaron un total de 1.239 manuscritos, y se seleccionaron 1.041. El número promedio de citas por año por manuscrito fue de 1,84 (rango intercuartil [RIC]: 0­2,33). El índice de impacto promedio fue de 47,8 (RIC: 20­111,6). La mediana del total de citas por manuscrito fue de 3 (RIC: 0­33.1), y el mayor número de citas por manuscrito fue de 484. La mayoría de las publicaciones se centran en los aspectos psicológicos de la DG, y hay una cantidad significativa de manuscritos relacionados con temas sociales y antropológicos. La mayoría de los artículos tienen un bajo nivel de evidencia científica. Conclusión Existe una gran cantidad de literatura publicada sobre disforia de género; sin embargo, existe un nivel significativo de desacuerdo en muchos aspectos sobre este tema. Con respecto a la afirmación quirúrgica, hace falta información respaldada por un alto nivel de evidencia que argumente la expansión emergente de las prácticas médicas.

Disfunción eréctil en personas con VIH ­ Revisión de alcance / Erectile Dysfunction in People with HIV ­ A Scoping Review

Objetivo Exponer los factores que han sido asociados al desarrollo de disfunción eréctil (DE) en las personas con virus de la inmunodeficiencia humana (VIH) y cuál es la prevalencia de la disfunción eréctil en esta población. Métodos Se realizó una revisión de alcance utilizando las siguientes bases de datos: MEDLINE, CENTRAL, Embase, Scopus, Lilacs, y Psycinfo. Los artículos incluidos debían tener cualquier información relacionada con la DE en personas con VIH, su prevalencia, y posibles factores asociados. Se filtraron un total de 2.726 artículos por título y resumen, y, de estos, se seleccionaron 22 referencias para revisión de texto completo y análisis. Resultados Se encontró que las personas con VIH tienen una mayor probabilidad de presentar DE en comparación con las personas sin VIH. Algunos estudios han establecido una asociación entre la DE y trastornos psicológicos o factores orgánicos, como la lipodistrofia, la hipertensión arterial, la hipercolesterolemia, la diabetes mellitus, la depresión, la ansiedad, y el hipogonadismo. La ingesta de terapia antirretroviral (TARV), más específicamente los inhibidores de la proteasa, sigue siendo cuestionada como causante de DE en pacientes con VIH. Conclusiones Ante un paciente con diagnóstico de VIH, se debe ahondar sobre DE con el fin de recomendar e iniciar conductas terapéuticas que aseguren un mejoramiento en su calidad de vida.

Aim To present factors that have been associated with the development of erectile dysfunction (ED) in people with human immunodeficiency virus (HIV) and the frequency of erectile dysfunction among this population. Methods We performed a scoping review on the following databases: MEDLINE, CENTRAL, Embase, Scopus, Lilacs, and Psycinfo. The articles included information related to ED in people with HIV, its frequency, and possible associated factors. A total of 2,726 articles were filtered by title and abstract, and, from these, 22 references were selected for full-text review and analysis. Results People with HIV were found to be more likely to have ED compared to people without HIV. Some studies have established an association between ED and psychological disorders or organic factors, such as lipodystrophy, high blood pressure, hypercholesterolemia, diabetes mellitus, depression, anxiety, and hypogonadism. The intake of antiretroviral therapy (ART), more specifically protease inhibitors, continues to be questioned as a cause of ED in patients with HIV. Conclusions In HIV-positive men, we recommend to actively seek ED in order to initiate therapeutic conducts that can ensure an improvement in their quality of life.

Disfunción sexual femenina: una mirada a los últimos 44 años. Análisis bibliométrico / Female Sexual Dysfunction: Looking Back at the Last 44 Years. A Bibliometric Analysis

Objetivo La disfunción sexual femenina (DSF) es un trastorno prevalente que afecta la calidad de vida de las mujeres y combina factores biológicos, psicológicos e interpersonales. Su estudio ha sido de poco interés, en campos como la investigación y el tratamiento, debido a la dificultad en la medición de las respuestas sexuales en las mujeres y otros factores, como el tabú acerca de la sexualidad femenina. Este estudio caracteriza las tendencias de publicaciones científicas acerca del tema, para que los urólogos puedan comprender la necesidad de realizar la búsqueda de este trastorno en la práctica diaria. Métodos Se realizó una búsqueda de la literatura en las bases de datos PubMed, FABUMED y Scopus, utilizando la estrategia «((«female sexual dysfunction¼ [Title/Abstract])¼. Se realizó un análisis bibliométrico descriptivo, de corte retrospectivo, de la literatura médica obtenida en MEDLINE. A través de las herramientas estadísticas FABUMED, PubReminer y Scopus, se recopilaron los datos y se obtuvo los resultados de las variables que posteriormente fueron analizadas de forma estadística y descriptiva. Con base en esta información, elaboramos tablas y gráficas en Microsoft Office Excel 2017. Adicionalmente, realizamos un análisis de mapeo bibliométrico utilizando el programa VOSviewer. Para la obtención del factor de impacto (FI), utilizamos el Journal Citation Reports 2017/2018. Resultados Desde 1975 hasta 2019, se publicaron 1.292 estudios, y la tasa anual de publicación permaneció estable entre 1975 y 2000. Pero, a partir del año 2000, se evidenció un aumento en el número de publicaciones, con un crecimiento del 92,1%. De las veinte revistas con más publicaciones, sólo cuatro son de urología. Los países con más publicaciones fueron: Estados Unidos (31,4%), Reino Unido (12,9%), Italia (8,9%), Turquía (5,9%), y Australia (4%). Estos datos son muy diferentes a los de los países de América Latina, en los que se encontraron muy pocas publicaciones, como Colombia, con tan sólo tres estudios. Conclusiones Este análisis bibliométrico mostró las diferentes tendencias y tasas de publicación de estudios sobre DSF, y evidenció una baja tasa de producción con relación a otras temáticas, sobre todo en las revistas urológicas, con predominio de mujeres como autores, aunque en los últimos años se ha identificado un crecimiento importante y sostenido. Se hace evidente la necesidad de desarrollar estrategias para mejorar la formación tanto en los niveles de posgrado como de pregrado y, así, generar más adhesión a este tema en una especialidad quirúrgica como la nuestra.

Objectives Female sexual dysfunction (FSD) is a prevalent disorder that affects the quality of life of women and combines biological, psychological, and interpersonal factors. There has been a lack of interest in studying FSD in such fields as research and treatment, due to the difficulty in measuring the sexual responses of women and other factors such as the taboo surrounding female sexuality. The present study portrays the trends in the scientific publications on the subject, so urologists can perceive and understand the need for research about this disorder in the daily practice. Methods A comprehensive review on the topic was performed through a PubMed, FABUMED, and Scopus databases using the search strategy "female sexual dysfunction", as well as a retrospective, descriptive, bibliometric analysis of the medical literature retrieved from MEDLINE. Data was collected through the FABUMED, PubReMiner, and Scopus statistical tools, and, based on the results obtained for the variables, which were later submitted to a statistical and descriptive analysis. Based on this data, tables and graphs were developed using the Microsoft Office Excel 2017 software. Moreover, we performed a bibliometric mapping analysis using the VOSviewer software. In order to obtain the impact factor (IF), we used the Journal Citation Reports 2017/2018. Results From 1975 to 2019, 1,292 studies were published; yearly publication rate remained stable from1975 to 2000, but after year 2000, an increase in the number of publications was evidenced, with a growth of 92.1%. But as of the year 2000, an increase in the number of publications was evidenced, with a growth of 92.1%. Of the twenty journals with the most publications, only four are on urology. The countries with the greatest number of publications were: the United States (31.4%), the United Kingdom (12.9%), Italy (8.9%), Turkey (5.9%), and Australia (4%). This data differs from that of Latin American countries, in which few publications were found, such as in Colombia, with only three studies. Conclusions The present bibliometric analysis showed the different trends and publication rates of studies on FSD, showing a low production rate as compared with that of other urological topics, especially in Urological journals, with a predominance of women as authors, although in recent years an important and sustained growth has been identified. The need to develop strategies to improve training at both the graduate and undergraduate levels and thus generate more adherence to these issues in a surgical specialty like ours is evident.