Diphtheria, a severe respiratory infection, was a major killer of children until the early years of the 20th century. Although diphtheria is now largely controlled globally thanks to vaccination, it is still endemic in some world regions and large epidemics can occur where vaccination coverage is insufficient. The pathological effects caused by its main virulence factor, diphtheria toxin, can be diminished by passive transfer of antibodies. Equine diphtheria antitoxin (eDAT), the cornerstone of treatment against toxinic complications of diphtheria, was invented more than 130 years ago, in 1890, and is still in use today. A method to concentrate anti-diphtheria antibodies from hyperimmune equine serum was described in the first issue of Memórias do Instituto Oswaldo Cruz in 1909. On this historic occasion, we present recent knowledge on taxonomic, epidemiological and clinical aspects of diphtheria agents that produce diphtheria toxin, and provide a historical perspective on eDAT treatment, adverse effects, threats on its scarce international supply, and current avenues for alternative therapeutic strategies.

ABSTRACT Dichotomius Hope, 1838 is one of the most diverse and abundant genera of dung beetles (Scarabaeidae: Scarabaeinae) in the New World. It congregates about 200 species distributed from the northeastern United States to central Argentina, and is arranged into four subgenera: Dichotomius s. str., Cephagonus Luederwaldt, 1929, Homocanthonides Luederwaldt, 1929 and Selenocopris Burmeister, 1846. The subgenus nominotypical has seen the least progress in its taxonomy, with only 15% of species with information in a recent revision. Therefore, in this paper, using a protocol for taxonomic revision and reviewing the type material and more than 12,000 specimens from 32 entomological collections, we have divided Dichotomius s. str. into two subgenera. We describe Dichotomius (Luederwaldtius) new subgenus to encompass, the smallest species (less than 20 mm), 13 species which previously belonged to D. sensu stricto, four species of Dichotomius (Selenocopris), and several undescribed species. Dichotomius triangulariceps (Blanchard, 1846) is transferred to the subgenus Selenocopris based on characters of the male genitalia. The subgenus Dichotomius s. str., in its new, more restricted sense, is delimited to include approximately 73 species arranged into, 12 species groups, plus two incertae sedis species. For each group, its definition is presented with species composition and geographic distribution. The incertae sedis species, D. agesilaus (Waterhouse, 1891) and D. compressicollis (Luederwaldt, 1929) (lectotype designated) are revised; the following information is presented for them: taxonomic history, species’ citation in published literature, redescription of males and females, list of material examined, photographs of the external morphology, male genitalia, and distribution map.

ABSTRACT Knowledge of neotropical freshwater gastrotrichs, especially in Brazil, has gained momentum in the past decades, with new species being discovered yearly, accumulating in the last 30 years more than 10% of known species worldwide. Nevertheless, there is still much to accomplish in the field, with large geographical gaps to be filled, especially in continental countries such as Brazil. In the present study, we report the partial results of an expedition that, for the first time, sampled the inland waters of Alagoas, Bahía, and Pernambuco states, Northeast Region, Brazil, and found ten species belonging to five genera of Chaetonotidae. We report the first occurrence in Brazil of Chaetonotus majestuosus Grosso & Drahg, 1984, originally described from Argentina, and the second record in Brazil of Chaetonotus dadayi Schwank, 1990, originally found in Paraguay, and the first occurrence beyond ‘terra typica’ of Heterolepidodermella jureiense Kisielewski, 1991, originally discovered in Southeastern Brazil. Furthermore, we report members of species in conformity to species originally described in European countries Chaetonotus cf. persetosus Zelinka, 1889, and Chaetonotus cf. oculifer Kisielewski, 1981, although further investigations are needed to confirm the occurrence of such widespread lineages. Finally, we list three putative undescribed species related to Lepidochaetus aff. zelinkai (Grünspan, 1908), Chaetonotus aff. hoanicus Schwank, 1990 and Chaetonotus aff. acanthocephalus Valkanov, 1937. This new survey increases the list of northeast Brazilian freshwater gastrotrichs to 13 species.

ABSTRACT Ephydrini comprises 118 species (plus seven nomina dubia species) that are distributed in all biogeographical regions except Antarctica. The tribe currently includes 13 genera, of which three (Calocoenia Mathis, Ephydra Fallén, Paracoenia Cresson) include subgenera. The subgenus Ephydra and three other genera (Neoephydra Mathis, Notiocoenia Mathis, Setacera Cresson) include species groups. Representatives of all these groupings (genera, subgenera, and in most cases also species groups) are included in the phylogenetic analysis and taxonomic treatment. To test the monophyly of Ephydrini and to understand phylogenetic relationships among genera, a cladistic analysis was performed using equal and implicit character weightings based on the morphology of adult males and females. Species of all 13 genera of Ephydrini from different geographical regions were included to account for morphological and phylogenetic diversity. Also included in the analysis are species of the other tribes of the subfamily Ephydrinae to provide greater perspective on the phylogenetic position of Ephydrini within the subfamily and to serve as outgroups. In our analyses, cladograms from both equal weighting and implied weighting resulted in cladograms of 261 steps in length. The tribes Ephydrini, Dagini, and Scatellini were recovered as monophyletic lineages. The tribe Dagini is the sister lineage to the node giving rise to the tribes Scatellini and Ephydrini, and the latter two tribes were recovered as sister groups. Within Ephydrini, the implied weighting cladogram provided higher resolution among terminal taxa with the same number of steps and is thus our preferred cladogram. In this cladogram, all currently valid genera, including subgenera and species groups, were recovered as monophyletic lineages. Thus, no taxonomic changes are needed at the genus-group level. In the taxonomic section, the tribe Ephydrini is characterized, as are all included genera within the tribe. In addition, keys to all genera, subgenera, and species groups are provided to facilitate their identification.

Haemosporida research started in the 19th century with the description of Plasmodium and other related parasites infecting mammals and birds. Here, we highlight the pioneering contributions of Henrique Aragão and Arthur Neiva in describing the first two Plasmodium species in lizards from the New World, Plasmodium diploglossi and Plasmodium tropiduri, published in the first printed issue of Memórias do Instituto Oswaldo Cruz in April 1909. We use these discoveries as a background to explore some historical and taxonomic aspects of Plasmodium species infecting reptiles, with a particular emphasis on the advancements made over the past 115 years in the Neotropics. Our review underscores the complexities and persistent challenges in the taxonomic classification of reptile haemosporidians and discusses some scientific advances in the field that improved our understanding of the biology and evolution of these parasites.

Free-living amoebas (FLA) are ubiquitous protists found in the environment. They have shown exceptional resistance to environmental challenges and play significant roles in controlling microbial populations through their predatory behaviour and microbicidal activity in both soil and aquatic ecosystems environments. However, although rare, a limited group of FLA can cause serious infections in the central nervous system and other diseases, particularly in immunocompromised individuals with high mortality rates. They can also cause keratitis in otherwise healthy individuals. This review offers a comprehensive overview of freshwater naked amoebae but does not cover all aspects in detail. Its goal is to provide a historical context for our current understanding while addressing the most critical elements of FLA biology, their pathogenic potential, and their interactions with important human pathogens.

BACKGROUND The works of Lutz & Neiva, published 115 years ago in the Memórias do Instituto Oswaldo Cruz, are pioneering for the study of Neotropical Tabanidae. These studies emphasised the importance of biological collections and the description of species from the exploration of South American areas. Dasybasis Macquart, 1847 has traditionally been considered a large genus of tabanids restricted to the Australasian, Neotropical, and Andean regions. Dasybasis species exhibit a high degree of morphological similarity, making specific differentiation challenging. Moreover, some of these features are also present in other taxa, suggesting that they may not be homologous characters and should not be used to define the genus. OBJECTIVES This study aimed to assess the monophyly of Dasybasis and establish its major monophyletic groups. METHODS We conducted an implied weighting analysis using morphological characters, and wing landmarks from 91 terminal species. FINDINGS For the total evidence analyses, aligning with either Tabanus Linnaeus or Dasybasis appendiculata Macquart yielded slightly different trees. Classical morphology and total evidence topology aligned with D. appendiculata are the same, while differing from the total evidence topology aligned with Tabanus in two nodes. MAIN CONCLUSIONS Our results indicate that Dasybasis was not a monophyletic group, and that this name should be restricted to species with a distribution in Australasia; while Neotropical Dasybasis species are recovered in different clades. The genera Archiplatius, Pseudoselasoma, and Stypommia are revalidated. This study provides a revised phylogenetic framework for “Dasybasis” and related taxa, highlighting the need for a more nuanced understanding of morphological character evolution within the tribe Diachlorini.

Resumen Introducción. La producción de banano es una de las actividades económicas más significativas para el país. Sin embargo, enfrenta serios desafíos debido a la presencia de diversos patógenos, entre los más significativos se encuentran los nematodos fitoparásitos que afectan el rendimiento y la calidad del cultivo. El uso de hongos nematófagos (HN) para el control biológico de nematodos es una alternativa para reducir la aplicación de productos químicos en cultivos agrícolas. En Costa Rica existe gran variedad de hongos debido a la diversidad de los suelos, por lo que el aislamiento y la correcta identificación de estos hongos es crucial para determinar su potencial antagonista. Objetivo. Aislar e identificar potenciales hongos nematófagos (PHN) presentes en muestras de suelo de plantaciones de banano de la región Huetar Atlántica. Materiales y métodos. Se analizaron seis muestras de suelo provenientes de cinco cantones de la región Huetar Atlántica de Costa Rica mediante el método de espolvoreado en placas con agar-agua en búsqueda de PHN. Para la selección y purificación de los PHN se utilizaron placas Petri con papa dextrosa agar (PDA), identificando las estructuras morfológicas para el diagnóstico a nivel de género. Los hongos identificados morfológicamente se replicaron y se conservaron en viales con PDA y en aceite mineral a 4°C. Se extrajo ADN de los PHN y mediante amplificación por PCR (Reacción de Cadena de la Polimerasa) y secuenciación de diferentes regiones del genoma (ITS, tef 1-alfa, rpb2 y β-tubulina), se identificaron molecularmente. Resultados. Se aislaron e identificaron doce hongos, entre ellos Trichoderma asperellum, Penicillium steckii, Purpureocillium lilacinum, Fusarium oxysporum, Fusarium sp., Fusarium pseudocircinatum, y Talaromyces sp. Conclusión. El descubrimiento e identificación correcta de PHN subraya la importancia de investigar su aplicación en programas de manejo integrado de plagas, así como la necesidad de evaluar su eficacia y seguridad en diferentes condiciones agroecológicas para maximizar su impacto positivo en la agricultura.

Abstract Introduction. Banana production is one of the most significant economic activities for the country. However, it faces serious challenges due to the presence of various pathogens, among the most significant are plant-parasitic nematodes that affect crop yield and quality. The use of nematophagous fungi (NF) for biological control of nematodes is an alternative to reduce the application of synthetic chemicals in agricultural crops. In Costa Rica there is a great variety of fungi due to the diversity of soils. Therefore, the isolation and correct identification of these fungi is crucial to determine their antagonistic potential. Objective. To isolate and identify the potential nematophagous fungi (PNF) present in soil samples from banana plantations at the Huetar Atlantic region. Materials and methods. Six soil samples from the Huetar Atlantic region of Costa Rica were analyzed by the agar-water sprinkling plates method in search of PNF. For PNF selection and purification, Petri dishes with potato dextrose agar (PDA) were used, identifying morphological structures for diagnosis at genus level. Morphologically identified fungi were replicated and preserved in vials with PDA and in mineral oil at 4°C. DNA was extracted from the isolated PNF and through PCR amplification (Polymerase Chain Reaction) and sequencing of different regions of the genome (ITS, tef 1-alpha, rpb2 and β-tubulin), they were molecularly identified. Results. Twelve fungi were isolated and identified, including Trichoderma asperellum, Penicillium steckii, Purpureocillium lilacinum, Fusarium oxysporum, Fusarium sp., Fusarium pseudocircinatum, and Talaromyces sp. Conclusion. The correct discovery and identification of PNF underscores the importance of investigating its application in integrated pest management programs, as well as the need to evaluate its efficacy and safety under different agroecological conditions to maximize its positive impact on agriculture.

Resumen Introducción: La serpiente marina pelágica Hydrophis platurus tiene el rango de distribución más amplio de todas las serpientes y es la única serpiente marina de aguas tropicales del oeste de América. Dentro de la variación en el patrón de color de esta especie, los ejemplares completamente amarillos se consideraban muy raros u ocasionales. Sin embargo, los patrones amarillos dominan una población establecida en el interior del Golfo Dulce en el Pacífico sur de Costa Rica. Objetivo: Monitoreamos y estudiamos la abundancia, patrones de actividad, morfometría y comportamiento alimentario del H. platurus amarillo dentro del Golfo Dulce. Métodos: Entre febrero 2009 y julio 2018, realizamos búsquedas mensuales de serpientes marinas desde una embarcación dentro del perímetro del Golfo Dulce. Resultados: Los adultos de la población de golfo son más pequeños que la población oceánica bicolor, con las hembras de cuerpos más grandes. Las serpientes del Golfo Dulce flotan y se mueven con las corrientes superficiales sin asociarse con líneas de deriva y escombros. Las serpientes se encuentran principalmente en aguas limpias y tranquilas con poca turbulencia. La dieta se compone de una amplia diversidad de peces pequeños, que capturan con un comportamiento depredador de acecho pasivo, flotando en la superficie. La presa es rápidamente capturada y tragada viva. Esta especie tiene una ausencia casi total de depredación, patrón que se extiende a esta población amarilla. Conclusiones: Las características del golfo y la dirección y fuerza de las corrientes superficiales en su entrada podrían restringir el tránsito de esta población amarilla hacia el exterior y el ingreso de las serpientes bicolores de la población oceánica. No consideramos prudente realizar cambios taxonómicos en esta población. La población amarilla es relativamente abundante dentro de la cuenca. Sin embargo, el alto tráfico turístico y otras actividades son factores de riesgo para su conservación. Políticas de protección deben crearse para preservar y proteger esta pequeña población de serpientes marinas amarillas, única dentro del rango de distribución de esta especie.

Abstract Introduction: The pelagic sea snake Hydrophis platurus has the broadest distributional range of all the snakes and is the only sea snake of tropical waters off the west coast of the Americas. Within the variation in the color pattern of this species, completely yellow specimens were considered very rare or occasional. However, a yellow pattern dominates a population established in the interior of the Golfo Dulce in the Southern Pacific of Costa Rica. Objective: We studied the abundance, activity patterns, morphometry, and feeding behavior of the yellow H. platurus within the Golfo Dulce. Methods: Between February 2009 and July 2018, we conducted surveys for sea snakes from a boat within the perimeter of the Golfo Dulce. Results: Adults from the gulf population are smaller than the bicolor oceanic population, with females having larger bodies. Sea snakes within the gulf float and move with surface currents without being linked to drift lines and debris. These snakes are mainly found in clean, calm waters with little turbulence. They feed on a wide diversity of small fish, which they capture using passive stalking predatory behaviors floating on the surface. Prey are quickly captured and swallowed alive. This species has an almost total absence of predation, a pattern that extends to this yellow population. Conclusions: The characteristics of the gulf and the direction and strength of the surface currents at its entrance might restrict the transit of this yellow population to the outside and the entry of the bicolored snakes of the oceanic population. We do not consider making taxonomic changes in this Golfo Dulce population prudent. This yellow population is relatively common within the basin. However, the high tourist traffic and other activities are risk factors for its conservation. Protection policies must be created to preserve and protect this small population of yellow sea snakes unique within this species’ distribution range.

Resumen Introducción. El garbanzo se consideró durante muchos años una especie de hospedero restringido para la nodulación, aunque estudios recientes describen una mayor diversidad bacteriana asociada al cultivo que permita incrementar los conocimientos acerca de esta simbiosis para obtener aislados eficientes en su contribución. Objetivo. Caracterizar e identificar un aislado obtenido a partir de nódulos de plantas de garbanzo y evaluar su efectividad en condiciones de campo. Materiales y métodos. La investigación se desarrolló en los laboratorios de dos centros: Instituto de Investigaciones Fundamentales en Agricultura Tropical “Alejandro de Humboldt”, Cuba y en el Centro Nacional de Recursos Genéticos, México, así como en condiciones campo en dos campañas durante los años 2018 y 2020, para demostrar su efectividad en la interacción del cultivo en el primer centro. El aislado R3 se identificó a nivel taxonómico mediante la secuenciación de cuatro genes. Para los experimentos en condiciones de laboratorio se utilizó un diseño completamente aleatorizado, mientras que los ensayos con plantas se realizaron bajo un diseño de bloques al azar. Los resultados fueron sometidos a un análisis de varianza y las medias se compararon según el test de Tukey (p < 0,05). Resultados. El aislado R3 mostró variabilidad en cuanto a sus características morfo-fisiológico y bioquímicas. Además, tuvo respuesta con diferencias significativas con respecto al resto de los tratamientos en los indicadores de crecimiento y rendimiento evaluados en el garbanzo. Conclusión. Se identificó por primera vez en Cuba Rhizobium pusense asociado a nódulos de garbanzo. La cepa mostró un crecimiento positivo a pH entre 5,5 y 9,0 y rangos de temperatura desde 29 ºC hasta 38 ºC, lo que evidencia su tolerancia a estos factores. Su inoculación en garbanzo estimuló la formación de nódulos e incrementó variables del rendimiento.

Abstract Introduction. Chickpea has been considered a restricted host species for nodulation, although recent studies describe a greater bacterial diversity associated with the crop to increase the knowledge about this symbiosis in orden to obtain efficient isolates in its contribution. Objective. To characterize and identify an isolate obtained from chickpea plant nodules and evaluate its effectiveness under field conditions. Materials and methods. The research was conducted in the laboratories of two centers: the Institute of Fundamental Research in Tropical Agriculture “Alejandro de Humboldt,” Cuba, and the National Center for Genetic Resources, Mexico, as well as under field conditions in two campaigns during the years 2018 and 2020 to demonstrate its effectiveness in crop interaction in the first center. The isolate R3 was taxonomically identified through the sequencing of four genes. For laboratory experiments, a completely randomized design was used, while plant trials were conducted under a randomized block design. The results were subjected to analysis of variance, and means were compared using the Tukey test (p<0.05). Results. The isolate R3 showed variability in terms of its morpho-physiological and biochemical characteristics. Furthermore, it exhibited significant differences compared to the other treatments in the growth and yield indicators evaluated in chickpea. Conclusions. Rhizobium pusense associated with chickpea nodules was identified for the first time in Cuba. The strain demonstrates growth at pH levels between 5.5 and 9.0 and temperature ranges from 29 °C to 38 °C, indicating its tolerance to these factors. Its inoculation in chickpea stimulates nodule formation and increased yield-related variables.

Resumen Los flujos actuales de información en línea han tomado dimensiones inmensurables, logrando con ello influir en las masas, tanto de forma positiva como negativa, permitiendo así la toma de decisiones y la generación de formas de pensar, que en diversas ocasiones resultan infundadas y provocan la desinformación. El análisis parte de la necesidad de generar una contribución epistémica en torno a los procesos de información en línea con fines de clasificación y caracterización general con especial enfoque hacia países emergentes (especialmente latinoamericanos) a través de la investigación documental. Esta propuesta identifica la construcción de una taxonomía de procesos de evaluación de la información, constituida en tres grupos generales: (1) los estructurados (provenientes de la educación formal y por medio de contenidos sistemáticos que provocan un aprendizaje explícito); (2) los no estructurados (adquiridos de forma deliberada, por medio de procesos no formales, que generan un aprendizaje tácito que no necesariamente es correcto o fundamentado); y (3) los complementarios (referidos a metodologías alternativas de diagnóstico sobre situaciones de desinformación). Se concluye presentando propuestas de diversas formas de intervención e identificación de mejores prácticas en razón de evitar sesgos en la mala interpretación, especialmente cuando la información es falsa.

Abstract Current online information flows have taken on immeasurable dimensions, thereby influencing the masses, both positively and negatively, thus allowing decision-making and the generation of ways of thinking, which on many occasions turn out to be unfounded and cause misinformation. The analysis is based on the need to generate an epistemic contribution around online information processes for the purposes of classification and general characterization with a special focus on emerging countries (especially Latin American) through documentary research. This proposal identifies the construction of a taxonomy of information evaluation processes, consisting of three general groups: (1) structured ones (coming from formal education and through systematic content that causes explicit learning); (2) unstructured ones (deliberately acquired, through non-formal processes, which generate tacit learning that is not necessarily correct or well-founded); and (3) complementary ones (referring to alternative methodologies for diagnosing misinformation situations). The paper concludes by presenting proposals for various forms of intervention and identifying best practices in order to avoid biases in misinterpretation, especially when the information is false.

Resumen. Muchos metazoos contienen moléculas capaces de fluorescencia, absorción y reemisión de luz. Dado que la distribución anatómica, o el patrón, de estas moléculas es variable entre taxones, los patrones de fluorescencia pueden servir como una poderosa herramienta diagnóstica en taxonomía y ecología. Sin embargo, los patrones de fluorescencia específicos de especie entre invertebrados marinos están poco comprendidos. Aquí, mostramos que los hidrozoos tienen diversos patrones de fluorescencia, que pueden ser el resultado de moléculas producidas intrínsecamente u obtenidas de fuentes dietéticas. Estudiamos hidrozoos, incluidos sifonóforos, hidromedusas e hidroides, en 5 órdenes de ambientes marinos pelágicos y bentónicos en Bocas del Toro, Panamá. Nuestros hallazgos muestran que los patrones de fluorescencia son muy prevalentes y pueden variar entre especies de hidrozoos y a lo largo del desarrollo. La mayoría de los taxa de hidrozoos examinados exhibieron alguna forma de fluorescencia, con variación observada entre las etapas de vida y las partes del cuerpo. Se documentó fluorescencia en el 88% de las hidromedusas (Leptothecata, Anthoathecata, Limnomedusae y Narcomedusae), el 50% de los hidroides y el 75% de los sifonóforos que se observaron en este estudio. Nuestros resultados ilustran cómo los patrones de fluorescencia pueden servir como una herramienta diagnóstica útil para explorar la biodiversidad marina, resaltando la necesidad de una mayor documentación de los patrones de fluorescencia en la diversidad marina y de investigar las moléculas que subyacen a este fenómeno.

Abstract. Many metazoans contain molecules capable of fluorescence, which is the absorption and re-emission of light. As the anatomical distribution, or patterning, of these molecules varies across taxa, fluorescence patterns may serve as a powerful diagnostic tool in taxonomy and ecology. However, species-specific fluorescence patterns in marine invertebrates are poorly understood. Here, we show that hydrozoans exhibit diverse fluorescence patterns, which may result from molecules that are produced intrinsically or obtained from dietary sources. We surveyed 5 orders of hydrozoans, including siphonophores, hydromedusae, and hydroids, from pelagic and benthic marine environments in Bocas del Toro, Panama. Our findings show that fluorescence patterns are highly prevalent and may vary across hydrozoan species throughout development. Most hydrozoan taxa exhibited some form of fluorescence, with variation observed among life stages and body parts. Fluorescence was documented in 88% of hydromedusae (Leptothecata, Anthoathecata, Limnomedusae, and Narcomedusae), 50% of hydroids, and 75% of siphonophores. Our results illustrate how fluorescence patterns can serve as a useful diagnostic tool to explore marine biodiversity, highlighting the need for further documentation of fluorescence patterns across marine taxa and research into the molecules that underlie this phenomenon.

The use of artificial intelligence in foreign language teaching, and particularly in teaching writing, is still under investigation for its potential positive impact and potential benefits. So far, the focus was on controversial uses, due to the challenges for the teachers. However, when used just for learning purposes, it can be a facilitating tool for the students. The key now is to understand its effects, challenges, and opportunities, to establish a framework for its use, and to make teachers aware of its potential. To this end, in this article we take a functional and utilitarian approach by identifying the characteristics and capacities of currently available sites. A description of the different sites is given along with their advantages and disadvantages. Since only a few fundamental works have been published on the subject, we propose a taxonomy with examples, evaluate its benefits and drawbacks and suggests potential applications for teaching and research.

ABSTRACT: The Socket Shield Technique (SST), a procedure utilized in dental implantology, entails retaining a section of the natural tooth root (the socket shield) in place when an adjacent tooth is extracted, and an implant is placed in the same area. While the technique presents certain advantages, numerous investigations into SST lack of well-designed prospective randomized clinical trials at long term, compromising the credibility and reliability of their findings. The objective of this study was to critically appraise and grade the level of evidence of a systematic review that compare the SST with the conventional immediate implant protocol (CIIP) for anterior tooth rehabilitation. A recent systematic review was appraised to assess the quality and consistency of the study findings. This assessment utilized the Strength of Recommendation Taxonomy (SORT) to facilitate the application of research results to clinical practice decision-making. The assessment of the quality and reliability of the systematic review and meta-analysis revealed that the evidence obtained from the study was graded with a strength of recommendation B and a level of evidence 2. SST seems to be a feasible procedure. However, there is insufficient evidence to recommend this technique as an alternative to CIIP in daily practice. Evidence from long-term studies with proper methodology and an adequate sample size is needed to support socket shield technique as an alternative treatment to the conventional immediate implant protocol.

RESUMEN: La técnica Socket Shield (SST), un procedimiento utilizado en implantología dental, implica retener una sección de la raíz natural del diente (cuando se extrae un diente adyacente y se coloca un implante en la misma área. Aunque la técnica presenta ciertas ventajas, numerosas investigaciones sobre la SST carecen de ensayos clínicos aleatorios prospectivos bien diseñados a largo plazo, comprometiendo la credibilidad y confiabilidad de sus hallazgos. El objetivo de este estudio fue evaluar críticamente y clasificar el nivel de evidencia de una revisión sistemática que compara la SST con el protocolo convencional de implante inmediato (CIIP) para la rehabilitación de dientes anteriores. Se evaluó una revisión sistemática reciente para analizar la calidad y consistencia de los hallazgos del estudio. Esta evaluación utilizó la Taxonomía de Fuerza de Recomendación (SORT) para facilitar la aplicación de los resultados de la investigación en la toma de decisiones clínicas. La evaluación de la calidad y confiabilidad de la revisión sistemática y metaanálisis reveló que la evidencia obtenida del estudio se clasificó con una fuerza de recomendación B y un nivel de evidencia 2. La SST parece ser un procedimiento factible. Sin embargo, hay evidencia insuficiente para recomendar esta técnica como alternativa al CIIP en la práctica diaria. Se necesitan estudios a largo plazo con una metodología adecuada y un tamaño de muestra suficiente para respaldar la técnica de Socket Shield como tratamiento alternativo al protocolo convencional de implante inmediato.

Resumo A acne é uma doença crónica, inflamatória e multifatorial da unidade pilossebácea, sem mortalidade associada, mas frequentemente acompanhada de alta morbilidade física e psicológica. A metformina, um antidiabético oral que diminui a glicemia, está a ser investigada como uma opção terapêutica no tratamento de acne em adultos e adolescentes. Os autores realizaram uma revisão baseada na evidência, de acordo com a metodologia PICO, com o objetivo de avaliar se existe evidência do uso da metformina (monoterapia ou adjuvante) no tratamento de acne em adultos e adolescentes na ausência de Síndrome do Ovário Poliquístico (SOP). No fim da pesquisa, cinco artigos originais foram considerados elegíveis para a revisão. Todos os estudos selecionados mostraram uma melhoria estatisticamente significativa nas lesões de acne nos pacientes que receberam metformina. Apesar do número reduzido de artigos incluídos na revisão, os resultados sugerem que a metformina pode ser utilizada como opção terapêutica na acne, embora seja necessária mais investigação. De acordo com a evidência atual, a metformina pode ser uma opção terapêutica no tratamento da acne sem SOP, com um nível de evidência B na SORT. Este tratamento demonstrou benefícios clínicos, particularmente na acne resistente a outros tratamentos ou em casos mais severos, melhorando o número e a gravidade das lesões.

Abstract Acne is a chronic, inflammatory, multifactorial disorder of the pilosebaceous unit, with no associated mortality but often accompanied by high physical and psychological morbidity. Metformin is an antihyperglycemic drug under investigation as a therapeutic option for acne in adults and adolescents. The authors performed an evidence-based review, according to the population, intervention, control, and outcomes methodology, to assess whether there is evidence for the use of metformin (monotherapy or adjuvant) in the treatment of acne in adolescents and adults in the absence of polycystic ovary syndrome (PCOS). At the end of the review method, five original studies were eligible for this review. All studies showed a statistically significant improvement in acne lesions in patients receiving metformin. Despite the small number of articles included in this review, results suggest that the use of metformin for the management of acne can be an option, although further investigation is required. According to the current evidence, metformin could be a therapeutic option in the treatment of acne without PCOS, with strength of recommendation taxonomy B level of evidence. This treatment has shown clinical benefits, particularly in acne resistant to other therapies or in more severe acne cases, improving the number and severity of the lesions.