La viruela sísmica aspectos relacionados a la fisiopatología, genoma, patogénesis, transmisión, replicación e inmunología / Aspects Related to pathophysiology, Genome, Pathogenesis, Transmission, Replication and Immunology of Monkeypox

Introducción: La viruela símica es una enfermedad zoonótica identificada por primera vez en 1958. El virus es un miembro del género Orthopoxvirus, de la familia Poxviridae. Infecta a una amplia variedad de mamíferos y se desconoce su reservorio natural. Objetivos: Describir los aspectos importantes relacionados a la fisiopatología, genoma, patogénesis, transmisión, replicación e inmunología de la viruela símica. Métodos: Se realizó una búsqueda de artículos originales, reportes de casos, revisiones bibliográficas y sistemáticas en el Portal Regional de la BVS, PubMed, Science, Nature y Lancet. Se consultaron los informes de la Organización Mundial de la Salud y la Organización Panamericana de la Salud sobre la viruela símica. Resultados: La propagación del virus de la viruela símica puede ocurrir a través del contacto cercano con lesiones, fluidos corporales, gotitas respiratorias y objetos contaminados. Una vez dentro del organismo, el virus infecta mucosas, células epiteliales y células inmunitarias de los tejidos adyacentes. El virus se replica y disemina rápidamente a través del sistema hemático y linfático. Las células T desempeñan un papel importante en la regulación de la respuesta inmunitaria contra el virus. Sin embargo, los Orthopoxvirus han desarrollado varios mecanismos para la evasión de la respuesta inmunitaria. Conclusiones: Los aspectos importantes descritos que se tuvieron en cuenta acerca de la transmisión de la viruela símica han tenido cambio significativo con el tiempo. El brote mundial de viruela símica de 2022 presentó una cadena de transmisión principalmente entre humanos asociada al contacto sexual(AU).

Introduction: Monkeypox is a zoonotic disease that was first identified in 1958. The virus is a member of Orthopoxvirus genus, of Poxviridae family. It infects wide variety of mammals and its natural reservoir is unknown. Objectives: To describe the important aspects related to pathophysiology, genome, pathogenesis, transmission, replication and immunology of monkeypox. Methods: A search of original articles, case reports, bibliographic and systematic reviews was carried out in VHL Regional Portal, PubMed, Science, Nature and Lancet. Reports from the World Health Organization and the Pan American Health Organization on monkeypox were consulted. Results: Spread of monkeypox virus can occur through close contact with lesions, body fluids, respiratory droplets, and contaminated objects. Once inside the body, the virus infects mucous membranes, epithelial cells and immune cells of adjacent tissues. The virus replicates and spreads rapidly through the blood and lymphatic system. T cells play an important role in regulating the immune response against the virus. However, Orthopoxviruses have developed several mechanisms to evade the immune response. Conclusions: The important aspects described, taken into account about monkeypox transmission, have significantly changed over time. 2022 global monkeypox outbreak presented a chain of transmission primarily among humans associated with sexual contact(AU)

Evaluation of virulence factors in clinical isolates of pathogenic E. coli in avian samples in Caloto, Colombia

Avian pathogenic E. coli (APEC), produces an extraintestinal infection in chickens, turkeys, and other types of birds, called colibacillosis, which is considered one of the main causes of economic losses due to morbidity, mortality, and discard of poultry carcasses. The objective of the present study was to characterize the genetic profile of the virulence factors of different isolates of avian E. coli in Caloto, Cauca, Colombia. Materials and methods: E. coli was isolated and identified by biochemical tests, from 47 clinical isolates. Subsequently, the DNA was extracted using Chelex. Three multiplex PCRs were designed to amplify 13 virulence factors (iroN, hlyF, iss, iutA, frz, vat, sitA, KpsM, sitD, fimH, pstB, sopB, and uvrY), using primers previously reported for each. At the end, the amplification products were verified on agarose gels. Each isolate was classified according to the number of virulence factors: group A (between 10 and 13), group B (between 5 and 9), and group C (4 or less). Discussion and Conclusions: we were able to identify the presence of a group of virulence factors in clinical isolates of APEC, which allows us to demonstrate that both the frequency and the profile of virulence factors in the isolated strains showed a different profile than the reported by other authors. The virulence genes pstB and fimH were detected in all our samples, and the iss gene was the one with the lowest frequency. Finally, according to the number of virulence factors, the group A was the most frequent.

La E. coli patógena aviar (APEC), produce una infección extraintestinal en pollos, pavos y otros tipos de aves, denominada colibacilosis, la cual es considerada una de las principales causas de pérdidas económicas por morbilidad, mortalidad y descarte de canales de aves. El objetivo del presente estudio fue caracterizar el perfil genético de los factores de virulencia de diferentes aislamientos de E. coli aviar en Caloto, Cauca, Colombia. Materiales y métodos: E. coli se aisló e identificó mediante pruebas bioquímicas, a partir de 47 aislamientos clínicos. Posteriormente, el ADN se extrajo utilizando Chelex. Se diseñaron tres PCR multiplex para amplificar 13 factores de virulencia (iroN, hlyF, iss, iutA, frz, vat, sitA, KpsM, sitD, fimH, pstB, sopB y uvrY), utilizando primers informados previamente para cada uno. Al final, los productos de amplificación fueron verificados en geles de agarosa. Cada aislamiento se clasificó según el número de factores de virulencia: grupo A (entre 10 y 13), grupo B (entre 5 y 9) y grupo C (4 o menos). Discusión y Conclusiones: pudimos identificar la presencia de un grupo de factores de virulencia en los aislados clínicos de APEC, lo que nos permite demostrar que tanto la frecuencia como el perfil de los factores de virulencia en las cepas aisladas presentaron un perfil diferente al reportado por otros autores. Los genes de virulencia pstB y fimH se detectaron en todas nuestras muestras, siendo el gen iss el de menor frecuencia. Finalmente, según el número de factores de virulencia, el grupo A fue el más frecuente.

Characterization of a Clostridioides difficile ST-293 isolate from a recurrent infection in Argentina

Resumen Clostridioides difficile es un patógeno esporulado oportunista responsable de diarrea asociada a antibióticos en humanos. C. difficile produce 2 toxinas principales: TcdAy TcdB, además de la toxina binaria (CDT), también asociada a la virulencia. Este estudio buscó caracterizar el aislamiento ALCD3, involucrado en un episodio de recurrencia de una infección nosocomial. La caracterización molecular mostró que dicho aislamiento pertenece al toxinotipo 0/v y el análisis por MLST demostró un perfil alélico adk:91, atpA:1, dxr:2, glyA: 1, recA:27, sodA: 1 y tpi:1, lo cual corresponde al ST293 (MLST clado 1). Durante el crecimiento, el aislamiento ALCD3 mostró un incremento temprano de la tasa de esporulación y valores máximos de formas termorresistentes luego de 2 días de incubación. Tanto la cinética de esporulación como la producción de formas termorresistentes fueron más rápidas en el aislamiento ALCD3 que en la cepa de referencia VPI 10463. La germinación en presencia del germinante natural taurocolato fue más rápida en el aislamiento ALCD3 que en la cepa VPI 10463, lo que indica que aquel comienza la hidrólisis del córtex antes. También, el co-germinante glicina indujo una rápida liberación de ácido dipicolínico en ALCD3. Estos hallazgos indican que el aislamiento ALCD3 es particularmente eficiente en la esporulación y en la germinación. El presente trabajo representa el primer informe de la circulación de C. difficile ST293 en Argentina. La habilidad del aislamiento ALCD3 para producir toxinas y su alta capacidad de esporulación/germinación son características claves compatibles con un alto potencial de diseminación e inducción de infecciones recurrentes.

Abstract Clostridioides difficile is an opportunistic spore-forming pathogen responsible for antibiotic-associated diarrhea in humans. C. difficile produces two main toxins: TcdA and TcdB as well as a third toxin named binary toxin (CDT) that is also involved in virulence. The present study aimed at characterizing the C. difficile isolate ALCD3 involved in a relapse episode of nosocomial infection. Molecular characterization showed that isolate ALCD3 belongs to tox-inotype 0/v and the MLST analysis demonstrated allelic profile adk:91, atpA:1, dxr:2, glyA: 1, recA:27, sodA: 1 and tpi:1 which corresponds to ST293 (MLST clade: 1). During growth, isolate ALCD3 showed an early increase in the sporulation ratio as well as maximal values of heat resis-tant forms after 2 days of incubation. Both sporulation kinetics and production of heat resistant forms were faster for isolate ALCD3 than for the reference strain VPI 10463. Germination in the presence of the natural germinant taurocholate was faster for isolate ALCD3 than for strain VPI 10463, which indicates that isolate ALCD3 starts cortex hydrolysis earlier than strain VPI 10463. Furthermore, the co-germinant glycine, induces rapid release of dipicolinic acid (DPA) in isolate ALCD3. These findings indicate that isolate ALCD3 is particularly efficient in both sporulation and germination. The present work represents the first report of the circulation of C. difficile ST293 in Argentina. The ability of isolate ALCD3 to produce toxins and its high sporulation/germination capacity are key features compatible with a microorganism with high dissemination potential and the possibility of inducing recurrent infections.

Maculopatía por inmunoganmapatía

La maculopatía por inmunoganmapatía es una enfermedad macular inusual caracterizada por la presencia de fluido intra y subretinal en asociación con ganmapatías monoclonales. Puede constituir la primera manifestación de enfermedad sistémica en un número considerable de pacientes. La infiltración de la retina neurosensorial y del espacio subretiniano por las inmunoglobulinas provoca un aumento de la presión osmótica lo cual genera acumulación del fluido intra y subretinal. El "silencio angiográfico" la distingue de otras maculopatías con desprendimientos serosos. La plasmaféresis combinada con quimioterapia constituye la primera línea del tratamiento. Aunque el líquido intrarretinal mejora considerablemente, el subretinal persiste en la mayoría de los ojos. La agudeza visual mejor corregida final muestra una ganancia de 0,3 décimas como promedio después del tratamiento. Con el objetivo de exponer contenido actualizado sobre maculopatía por inmunoganmapatía, se realizó una revisión de las publicaciones más relevantes relacionadas con el tema durante los últimos ocho años.

Immunoganmapathy maculopathy is an unusual macular disease characterized by the presence of intra- and subretinal fluid in association with monoclonal ganmapathies. It may constitute the first manifestation of systemic disease in a considerable number of patients. Infiltration of the neurosensory retina and the subretinal space by immunoglobulins causes an increase in osmotic pressure which leads to accumulation of intra- and subretinal fluid. The "angiographic silence" distinguishes it from other maculopathies with serous detachment. Plasmapheresis combined with chemotherapy is the first line of treatment. Although intraretinal fluid improves considerably, subretinal fluid persists in most eyes. The final best-corrected visual acuity shows a gain of 0.3 tenths on average after treatment. In order to expose updated content on immunoganmopathy maculopathy, a review of the most relevant publications related to the subject during the last eight years was performed.

Viruela símica: una revisión narrativa de la fisiopatología

La viruela símica es una enfermedad zoonótica identificada por primera vez en 1958. El virus es un miembro del género Orthopoxvirus, de la familia Poxviridae. Infecta a una amplia variedad de mamíferos, pero se desconoce su reservorio natural. El virus del brote de 2022 pertenece a los clados IIa y IIb. Es probable que la aparición del brote actual se deba a las importaciones del brote de Nigeria de 2017-2018. La propagación de persona a persona puede ocurrir a través del contacto cercano con lesiones, fluidos corporales, gotitas respiratorias y objetos contaminados. Una vez dentro del organismo, el virus infecta las mucosas, células epiteliales y células inmunitarias de los tejidos adyacentes. Luego, el virus se replica y disemina rápidamente a través del sistema hemático y linfático. Las células T desempeñan un papel importante en la regulación de la respuesta inmunitaria contra el virus. Sin embargo, los Orthopoxvirus han desarrollado varios mecanismos para la evasión de la respuesta inmunitaria. La vigilancia de la enfermedad es un factor crucial en la evaluación de riesgo del virus y del control del brote. Para esta revisión se realizó la búsqueda de los principales artículos relacionados a la patogenia del virus, publicados hasta la fecha. El artículo destaca la necesidad de nuevos estudios sobre transmisibilidad y patogenicidad de las cepas asociadas al brote de 2022.

Monkeypox is a zoonotic disease first identified in 1958. The virus is a member of the genus Orthopoxvirus, family Poxviridae. It infects a wide variety of mammals, but its natural reservoir is unknown. The virus in the 2022 outbreak belongs to clades IIa and IIb. The emergence of the current outbreak is likely to be due to importations from the 2017-2018 Nigerian outbreak. Person to person spread can occur through close contact with lesions, body fluids, respiratory droplets and contaminated objects. Once inside the body, the virus infects mucous membranes, epithelial cells and immune cells in adjacent tissues. The virus then replicates and spreads rapidly through the blood and lymphatic system. Tcells play an important role in regulating the immune response against the virus. However, Orthopoxvirus have evolved several mechanisms for evasion of the immune response. Disease surveillance is a crucial factor in virus risk assessment and outbreak control. For this review we searched for the main articles related to the pathogenesis of the virus published to date. The article highlights the need for further studies on transmissibility and pathogenicity of the strains associated with the 2022 outbreak.

Characterization of a Clostridioides difficile ST-293 isolate from a recurrent infection in Argentina.

Clostridioides difficile is an opportunistic spore-forming pathogen responsible for antibiotic-associated diarrhea in humans. C. difficile produces two main toxins: TcdA and TcdB as well as a third toxin named binary toxin (CDT) that is also involved in virulence. The present study aimed at characterizing the C. difficile isolate ALCD3 involved in a relapse episode of nosocomial infection. Molecular characterization showed that isolate ALCD3 belongs to toxinotype 0/v and the MLST analysis demonstrated allelic profile adk:91, atpA:1, dxr:2, glyA: 1, recA:27, sodA: 1 and tpi:1 which corresponds to ST293 (MLST clade: 1). During growth, isolate ALCD3 showed an early increase in the sporulation ratio as well as maximal values of heat resistant forms after 2 days of incubation. Both sporulation kinetics and production of heat resistant forms were faster for isolate ALCD3 than for the reference strain VPI 10463. Germination in the presence of the natural germinant taurocholate was faster for isolate ALCD3 than for strain VPI 10463, which indicates that isolate ALCD3 starts cortex hydrolysis earlier than strain VPI 10463. Furthermore, the co-germinant glycine, induces rapid release of dipicolinic acid (DPA) in isolate ALCD3. These findings indicate that isolate ALCD3 is particularly efficient in both sporulation and germination. The present work represents the first report of the circulation of C. difficile ST293 in Argentina. The ability of isolate ALCD3 to produce toxins and its high sporulation/germination capacity are key features compatible with a microorganism with high dissemination potential and the possibility of inducing recurrent infections.

Linfoma de Hodgkin clásico: diferentes caras, una misma entidad / Classic Hodgkin lymphoma: different faces, same entity

El linfoma de Hodgkin clásico es una neoplasia linfoide maligna derivada de las células B del centro germinal, que corresponde aproximadamente al 85 % de los casos de linfoma de Hodgkin. Esta entidad afecta principalmente a pacientes jóvenes, y cuenta con un excelente pronóstico gracias a los avances en los métodos diagnósticos para su estadificación y tratamiento. Su enfoque diagnóstico correcto y completo requiere de una historia clínica exhaustiva y una biopsia de ganglio linfático adecuada para el análisis e identificación de los hallazgos histopatológicos e inmunohistoquímicos característicos, ya que a diferencia de otros linfomas donde las células neoplásicas son una población importante o dominante, las células de Hodgkin y Reed-Sternberg generalmente representan menos del 10 % de la lesión tumoral. Aunque todavía falta mucho por entender sobre la naturaleza biológica de este linfoma y sus diferentes subtipos, en los últimos años se ha avanzado considerablemente en la comprensión de su linfomagénesis, especialmente cuando está relacionada con la infección por el virus de Epstein-Barr. Su alta heterogeneidad y posible superposición morfológica, obligan a continuar su estudio para poder identificarlo, al igual que a sus posibles diagnósticos diferenciales en aquellos casos donde se presente con una variante o patrón infrecuente. Este artículo pretende ofrecer una descripción integral resumida y actualizada sobre la fisiopatología, la clínica, el diagnóstico histopatológico con énfasis en aquellos patrones raros que podrían llegar a ser factores distractores y de confusión, y el pronóstico del linfoma de Hodgkin clásico, buscando lograr una mejor comprensión de la enfermedad

Classic Hodgkin lymphoma is a malignant lymphoid neoplasm derived from B cells in the germinal center, and accounts for approximately 85% of all Hodgkin lymphoma cases. This disease mainly affects young patients and has an excellent prognosis due to advances in diagnostic methods for staging and treatment. A correct and complete diagnostic approach requires a thorough clinical history and an adequate lymph node biopsy for the analysis and identification of characteristic histopathological and immunohistochemical findings. Unlike other lymphomas where neoplastic cells are an important or dominant population, Reed-Sternberg/ Hodgkin cells generally represent less than 10% of the tumor lesion. Although much remains to be understood about the biological nature of this lymphoma and its different subtypes, considerable progress has been made in understanding its lymphomagenesis in recent years, especially when it is related to Epstein-Barr virus infection. Its high heterogeneity and possible morphological overlap require ongoing study to identify it and its possible differential diagnoses in cases where it presents with a rare variant or pattern. This article aims to provide a comprehensive updated summary on the pathophysiology, clinical presentation, histopathological diagnosis, with emphasis on rare patterns that could become distracting and confusing factors, and prognosis of classic Hodgkin lymphoma, seeking to achieve a better understanding of the disease

The clinical characteristics of Hirayama disease in females.

INTRODUCTION: To characterize Hirayama disease in female patients, and increase awareness among clinicians regarding the specifics of this disease. METHODS: Baseline data, clinical manifestations, characteristics of cervical-flexion magnetic resonance imaging, and electromyography were collected and compared among females and males with Hirayama disease. In addition, the literature on Hirayama disease in females up to October, 2021 was searched in PubMed and the relevant data were compared with the data from our study. RESULTS: Twenty female and 40 male patients were included in this study. The average ages of onset and menarche were 14.65 and 12.75 years old. All patients suffered from muscular weakness and atrophy of the upper limb(s), with flattening and/or atrophy of the lower cervical spinal cords in cervical-flexion magnetic resonance imaging, and neurogenic patterns in the atrophic muscles as determined using electromyography. The age of onset in females was about 2 years later than the age of menarche, and the age of onset in females was 2 years earlier than that in males. There were no obvious differences in clinical presentation between males and females. DISCUSSION: Although females presented with Hirayama disease two years earlier than males, no other clinical differences were observed. Hirayama disease is likely associated with growth and development in puberty, and early identification, regardless of whether patients are male or female, is critical to optimizing prognosis.

Etiopatogenia de las uñas frágiles / Etiopathogenesis of brittle nails

Las uñas frágiles se caracterizan por ser quebradizas, de superficie áspera y descamativa, es una entidad que predomina en mujeres y afecta principalmente las uñas de las manos. En condiciones normales las uñas estás compuestas por agua, cuya concentración oscila entre 7 % al 18 %, lípidos entre 0,1 % y 5%, siendo el colesterol su principal componente, además están compuesta por células queratinizadas sin descamación, dando origen a tres capas histológicas llamadas dorsal, media y ventral. Estas también contienen trazas de elementos como hierro y zinc. La alteración y disminución de estos componentes favorecen está condición. La causa puede ser idiopática o secundaria a enfermedades sistémicas, pueden estar presentes en algunas patologías dermatológicas. Una correcta anamnesis e historia clínica son necesarias para un correcto abordaje terapéutico. Su implicación cosmética nos obliga a tener un conocimiento claro de su etiopatogenia para así poder establecer un tratamiento efectivo y oportuno(AU)

Brittle nails are characterized by being brittle, witha rough and scaly surface, it is an entity that predominates inwomen and mainly affects the fingernails. In normal conditions the nails are made up of water, whose concentration ranges from7% to 18%, lipids between 0.1% and 5%, with cholesterol beingits main component, they are also composed of keratinized cellswithout desquamation, giving rise to three histological layerscalled dorsal, middle and ventral. These also contain traces ofelements such as iron, and zinc. The alteration and decreaseof these components favor this condition. Yhe cause may beidiopathic or secondary to systemic diseases, they may be presentin some dermatological pathologies. A correct anamnesis andmedical history are necessary for a correct therapeutic approach.Its cosmetic involvement forces us to have a clear understandingof its pathogenesis in order to establish an effective and timelytreatment(AU)

Multi-organ pathological findings associated with COVID-19 in postmortem needle core biopsies in four patients and a review of the current literature.

Coronavirus disease 2019 (COVID-19) has spread worldwide, resulting in significant morbidity and mortality. Histopathological findings are essential in understanding its pathogenesis and we present our findings from postmortem core needle biopsies in an attempt to share information that may shed some light on this severe pandemic. Different organ samples from four patients with PCR-confirmed COVID-19 at the Infanta Sofía Hospital (Madrid) were studied during the months of April and May, 2020 by six pathologists using routine stains, histochemistry and immunohistochemistry. Results were compared with other reported cases. All patients had a clinical diagnosis of pneumonia and biopsies revealed lung damage in the majority. Heart, liver, spleen and kidney were also studied and abnormalities were found in all cases and are extensively described. The histopathology of organs affected by COVID-19 is vital to the understanding of this disease and its sequelae.

Genes implicados en la gravedad de la infección por SARS-cov- 2

Resumen El COVID-19 es una patología producida por el SARS-CoV-2, virus de carácter zoonótico capaz de producir patologías multiorgánicas. La sintomatología que produce es variada. Ante la infección algunos pacientes presentan condiciones de gravedad. Los estudios han demostrado que el rol genético tiene gran afluencia sobre la respuesta ante la infección. El objetivo de investigación es detallar los genes que están implicados en la gravedad de la infección por SARS-CoV- 2. Metodología . Se realizó una revisión sistemática, con base a la búsqueda y análisis de artículos originales en bases de datos de alto impacto como PudMed, Google Académico, Scopus, Taylor & Francis, ProQuest SciencieDirect; se utilizaron operadores booleanos, criterios de inclusión y exclusión con el objetivo de obtener información precisa. Los genes de inmunidad como el HLA, ACE2 y TMPRSS2 están directamente involucrados con la gravedad de la infección por SARS-CoV- 2. Los polimorfismos de los genes del polyQ del receptor de andrógenos, factor ABO coadyuvan a un deterioro del estado patológico como consecuencia de la COVID-19. Conclusión. Los estudios demostraron que existen genes involucrados en la gravedad ante la infección de SARS -CoV-2, pues mencionan que los polimorfismos de los genes; HLA, del polyQ del receptor de andrógenos y factor ABO producen susceptibilidad ante el COVID-19. Así mismo los genes ACE2 y TMPRSS2 intervienen en el ingreso y expansión del virus. En las diversas razas existen variantes de los genes CCL2 y MBL lo que indica que algunas poblaciones son más susceptibles que otras.

Abstract COVID-19 is a pathology caused by SARS-CoV-2, a zoonotic virus capable of producing multi-organ pathologies. The symptomatology it produces is varied. Some patients present severe conditions after infection. Studies have shown that the genetic role has a great influence on the response to infection. Methodology . A systematic review was carried out, based on the search and analysis of original articles in high impact databases such as PudMed, Google Scholar, Scopus, Taylor & Francis, ProQuest SciencieDirect; Boolean operators, inclusion and exclusion criteria were used in order to obtain accurate information. Immunity genes such as HLA, ACE2 and TMPRSS2 are directly involved with the severity of SARS-CoV- 2 infection. Polymorphisms of androgen receptor polyQ genes, ABO factor contribute to a deterioration of the pathological state as a consequence of COVID-19. Conclusion . The studies demonstrated that there are genes involved in the severity of SARS-CoV-2 infection, since they mention that polymorphisms of the HLA, androgen receptor polyQ and ABO factor genes produce susceptibility to COVID-19. Likewise, ACE2 and TMPRSS2 genes intervene in the entry and expansion of the virus. In the different breeds there are variants of the CCL2 and MBL genes, which indicates that some populations are more susceptible than others.

Resumo COVID-19 é uma patologia causada pelo SARS-CoV-2, um vírus zoonótico capaz de produzir patologias multiorganismos. Os sintomas que ela produz são variados. Alguns pacientes se apresentam com condições severas após a infecção. Estudos demonstraram que o papel da genética desempenha um papel importante na resposta à infecção. O objetivo desta pesquisa é detalhar os genes que estão envolvidos na gravidade da infecção pelo SARS-CoV- 2. Metodologia. Foi realizada uma revisão sistemática, baseada na busca e análise de artigos originais em bancos de dados de alto impacto como PudMed, Google Scholar, Scopus, Taylor & Francis, ProQuest SciencieDirect; operadores booleanos, critérios de inclusão e exclusão foram utilizados para obter informações precisas. Resultados. Os genes de imunidade como HLA, ACE2 e TMPRSS2 estão diretamente envolvidos na gravidade da infecção pelo SARS-CoV- 2. Os polimorfismos dos genes receptores de androgênio polyQ, fator ABO contribuem para uma deterioração do estado patológico como conseqüência da COVID-19. Conclusão. Os estudos demonstraram que existem genes envolvidos na gravidade da infecção pelo SRA-CoV-2, pois mencionam que os polimorfismos dos genes HLA, androgênio receptor policarbonato e fator ABO produzem suscetibilidade à COVID-19. Os genes ACE2 e TMPRSS2 também estão envolvidos na entrada e propagação do vírus. Existem variantes dos genes CCL2 e MBL nas diferentes raças, indicando que algumas populações são mais suscetíveis do que outras.

Role of Inflammasome Activation in Systemic Lupus Erythematosus: Are Innate Immune Cells Activated? / Rol de la activación del inflammasome en lupus eritematoso sistémico: están las células del sistema inmune innato activados?

Background: Systemic lupus erythematosus (SLE) is characterized by a wide spectrum of clinical and immunological abnormalities. New data have emerged about the role of inflammasomes in autoimmune diseases. We aimed to investigate whether basal inflammasome activation occurs in SLE patients, and whether a relationship between inflammasome-related-cytokines and disease activity exists. Methods: Fourteen (14) consecutive SLE patients and 13 healthy individuals, matched by sex, age and ethnicity, were included. Demographics, laboratory and clinical data were recorded. Peripheral blood mononuclear cells (PBMCs) from patients and controls were obtained and monocytes were isolated by negative selection. Purified monocytes were stimulated with LPS in the presence or absence of Caspase-1 inhibitor. CD14 and Caspase-1 expression were analyzed by flow cytometry. Cytokine levels were determined in plasma and culture supernatants by ELISA. Student's t test and Mann–Whitney tests were used for statistical analysis. Results: The percentage of CD14+/Caspase-1+ was significantly higher in monocytes from SLE patients compared to normal controls (p<0.01). These findings paralleled with higher plasma levels of IL-1β (p<0.05) and IL-18 (p<0.01) in those patients. Purified monocytes from SLE patients displayed a robust inflammatory response after LPS stimulation where Caspase-1, IL-1β and IL-18 were highly expressed. Plasma levels of IL-18 were also significantly higher in SLE patients with active disease (p<0.05). In addition, the production of IL-18 was reduced by 3 fold when Caspase-1 inhibitor was added to the cultures. Conclusions: Monocytes from SLE patients exhibited increased inflammasome activation, characterized by high expression of Caspase-1, IL-1β and IL-18. Caspase-1 specific inhibitor decreased inflammasome activation (in vitro) by suppressing the production of IL-18.(AU)

Introducción: El lupus eritematoso sistémico (LES) se caracteriza por presentar diversas anormalidades clínicas e inmunológicas. El ensamblaje de los componentes del inflamasoma da lugar a la activación de caspasa-1, generando la liberación de citoquinas pro-inflamatorias IL-1β e IL-18. Objetivos: Evaluar si existe una activación basal del inflamasoma en pacientes con LES y determinar la asociación de las citoquinas IL-1β e IL-18 con la actividad de la enfermedad. Materiales y métodos: Se incluyeron 14 (n=14) pacientes consecutivos con LES y 13 (n=13) controles, pareados por edad, sexo y raza. Se recogieron datos clínicos, demográficos y de laboratorio. Los monocitos fueron aislados a partir de células mononucleares de sangre periférica obtenidas de pacientes y controles. Los monocitos purificados fueron estimulados con LPS, en presencia y ausencia de inhibidor de caspasa-1. La expresión de CD14 y caspasa-1 fueron determinados por citometría de flujo. Niveles de citoquinas fueron determinadas en plasma y en sobrenadantes de cultivos mediante técnica de ELISA. Test de Student y Mann-Whitney fueron usados para el análisis estadístico. Resultados: El porcentaje de CD14+/caspasa-1+ fue significativamente superior en monocitos de pacientes con LES vs. controles (p<0,01). En forma paralela, se encontraron niveles plasmáticos significativamente superiores de IL-1β (p<0,05) y de IL-18 (p<0,01) en pacientes con LES. Monocitos purificados de pacientes lúpicos presentaron una robusta respuesta inflamatoria luego de ser estimulados con LPS, donde caspasa-1, IL-1β e IL-18 fueron altamente expresados. Niveles plasmáticos de IL-18 fueron significativamente mayores en pacientes con LES y enfermedad activa (p<0,05). Por otro lado, la producción de IL-18 se redujo casi 3 veces cuando se agregó inhibidor de caspasa-1 en cultivos.(AU)

Epithelial-to-mesenchymal transition induced by virus / Transición epitelio-mesénquima inducida por virus

RESUMEN La Transición Epitelio-Mesénquima (EMT) es un proceso de diferenciación altamente conservado en vertebrados. Este ocurre en células epiteliales con la activación progresiva de la pérdida de la polaridad, la adquisición de motilidad individual y la capacidad invasiva a otros tejidos. La EMT es un proceso normal durante el desarrollo; no obstante, en condiciones patológicas está relacionada con la inducción de metástasis, lo cual representa una vía alterna al desarrollo de procesos oncogénicos tempranos. Aunque la EMT es activada principalmente por factores de crecimiento, también se puede desencadenar por infecciones de patógenos intracelulares mediante la activación de rutas moleculares inductoras de este proceso. Por lo tanto, una infección bacteriana o viral pueda generar predisposición al desarrollo de tumores. Nuestro interés está enfocado principalmente en caracterizar la relación virus-hospedero, y en el caso de los virus, varios ya se han descrito como inductores de la EMT. En este artículo de revisión se describen el fenómeno de la plasticidad celular y la ocurrencia detallada del proceso de EMT, los patógenos virales reportados como inductores, los mecanismos moleculares usados para ello y las vías de regulación mediante miRNAs. Por último, se discute cómo esta relación virus-hospedero puede explicar la patogénesis de la enfermedad causada por Dengue virus, favoreciendo la identificación de blancos moleculares para terapia, estrategia conocida como Antivirales dirigidos a blancos celulares o HTA (Host-targeting antivirals).

ABSTRACT Epithelial-to-Mesenchymal Transition (EMT) is a highly conserved dedifferentiation process in vertebrates. This process occurs in epithelial cells activating progressive loss of cell polarity, acquisition of individual motility and invasive capacity to other tissues. EMT is a normal process during development process, however, in pathological conditions is related to the induction of metastasis, which represents an alternative path to the development of early oncogenic processes. Although, EMT is mainly activated by growth factors, it can also be triggered by intracellular-pathogen-infections by activating molecular pathways that induce this process. Therefore, a bacterial or viral infection may generate predisposition to the development of tumors. Our interest is mainly focused on characterizing the host-virus relationship, and in the case of viruses, several have already been described as EMT inductors. In this review, phenomenon of cellular plasticity, detailed occurrence of the EMT, viral pathogens reported as inducers, the molecular mechanisms, and the regulatory pathways through miRNAs are described. Finally, we discuss how this host-virus relationship may explain the pathogenesis of the disease caused by Dengue virus, favoring the identification of molecular targets for therapy, a strategy known as Host-Targeting Antivirals (HTA).

Molecular biology of coronaviruses: an overview of virus-host interactions and pathogenesis.

Coronaviruses (CoV) are enveloped, plus-strand RNA viruses that have the largest known RNA genomes and infect birds and mammals, causing various diseases. Human coronaviruses (HCoVs) were first identified in the mid-1960s and have been known to cause enteric or respiratory infections. In the last two decades, three HCoVs have emerged, including the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which initiated the ongoing pandemic. SARS-CoV-2 causes a respiratory illness that presents as a mild upper respiratory disease but may result in acute respiratory distress syndrome, multi-organ failure and can be fatal, especially when underlying comorbidities are present. Children account for a low percentage of coronavirus disease 2019 (COVID-19) cases, with seemingly less severe disease. Most pediatric patients present mild or moderate symptoms or are asymptomatic. However, some cases may be severe. Therefore, SARS-CoV-2 infection and COVID-19 in pediatric patients must be studied in detail. This review describes general features of the molecular biology of CoVs and virus-host interactions that may be implicated in the pathogenesis of SARS-CoV-2.

Los coronavirus son virus envueltos de ARN de polaridad positiva, con los genomas más grandes que se conocen. Infectan aves y mamíferos, y causan una amplia variedad de enfermedades. Los coronavirus humanos se identificaron a mediados de la década de 1960 y se sabe que causan infecciones entéricas y respiratorias. En las últimas dos décadas han emergido tres coronavirus humanos pandémicos, incluido el coronavirus 2 del síndrome agudo respiratorio grave (SARS-CoV-2) que ha causado la pandemia actual. El SARS-CoV-2 produce enfermedad respiratoria que se presenta con padecimientos moderados de las vías respiratorias altas, pero puede resultar en síndrome respiratorio agudo, falla multiorgánica y muerte, en especial en casos con morbilidad subyacente. Los casos de COVID-19 en niños representan un porcentaje bajo y con síntomas menos graves de la enfermedad. La mayoría de los pacientes pediátricos son asintomáticos o presentan enfermedad leve o moderada; sin embargo, también en niños la enfermedad puede ser grave, por lo que la infección con SARS-CoV-2 y la COVID-19 en pacientes pediátricos deben estudiarse con detalle. En esta revisión se describen las características generales de la biología molecular de los coronavirus y de las interacciones virus-hospedero que se conocen para los coronavirus humanos identificados previamente, y que podrían estar implicados en la patogénesis del SARS-CoV-2.

Molecular biology of coronaviruses: an overview of virus-host interactions and pathogenesis / Biología molecular de los coronavirus: una visión panorámica de las interacciones virus-hospedero y de la patogénesis

Abstract Coronaviruses (CoV) are enveloped, plus-strand RNA viruses that have the largest known RNA genomes and infect birds and mammals, causing various diseases. Human coronaviruses (HCoVs) were first identified in the mid-1960s and have been known to cause enteric or respiratory infections. In the last two decades, three HCoVs have emerged, including the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which initiated the ongoing pandemic. SARS-CoV-2 causes a respiratory illness that presents as a mild upper respiratory disease but may result in acute respiratory distress syndrome, multi-organ failure and can be fatal, especially when underlying comorbidities are present. Children account for a low percentage of coronavirus disease 2019 (COVID-19) cases, with seemingly less severe disease. Most pediatric patients present mild or moderate symptoms or are asymptomatic. However, some cases may be severe. Therefore, SARS-CoV-2 infection and COVID-19 in pediatric patients must be studied in detail. This review describes general features of the molecular biology of CoVs and virus-host interactions that may be implicated in the pathogenesis of SARS-CoV-2.

Resumen Los coronavirus son virus envueltos de ARN de polaridad positiva, con los genomas más grandes que se conocen. Infectan aves y mamíferos, y causan una amplia variedad de enfermedades. Los coronavirus humanos se identificaron a mediados de la década de 1960 y se sabe que causan infecciones entéricas y respiratorias. En las últimas dos décadas han emergido tres coronavirus humanos pandémicos, incluido el coronavirus 2 del síndrome agudo respiratorio grave (SARS-CoV-2) que ha causado la pandemia actual. El SARS-CoV-2 produce enfermedad respiratoria que se presenta con padecimientos moderados de las vías respiratorias altas, pero puede resultar en síndrome respiratorio agudo, falla multiorgánica y muerte, en especial en casos con morbilidad subyacente. Los casos de COVID-19 en niños representan un porcentaje bajo y con síntomas menos graves de la enfermedad. La mayoría de los pacientes pediátricos son asintomáticos o presentan enfermedad leve o moderada; sin embargo, también en niños la enfermedad puede ser grave, por lo que la infección con SARS-CoV-2 y la COVID-19 en pacientes pediátricos deben estudiarse con detalle. En esta revisión se describen las características generales de la biología molecular de los coronavirus y de las interacciones virus-hospedero que se conocen para los coronavirus humanos identificados previamente, y que podrían estar implicados en la patogénesis del SARS-CoV-2.

Role of Inflammasome Activation in Systemic Lupus Erythematosus: Are Innate Immune Cells Activated?

BACKGROUND: Systemic lupus erythematosus (SLE) is characterized by a wide spectrum of clinical and immunological abnormalities. New data have emerged about the role of inflammasomes in autoimmune diseases. We aimed to investigate whether basal inflammasome activation occurs in SLE patients, and whether a relationship between inflammasome-related-cytokines and disease activity exists. METHODS: Fourteen (14) consecutive SLE patients and 13 healthy individuals, matched by sex, age and ethnicity, were included. Demographics, laboratory and clinical data were recorded. Peripheral blood mononuclear cells (PBMCs) from patients and controls were obtained and monocytes were isolated by negative selection. Purified monocytes were stimulated with LPS in the presence or absence of Caspase-1 inhibitor. CD14 and Caspase-1 expression were analyzed by flow cytometry. Cytokine levels were determined in plasma and culture supernatants by ELISA. Student's t test and Mann-Whitney tests were used for statistical analysis. RESULTS: The percentage of CD14+/Caspase-1+ was significantly higher in monocytes from SLE patients compared to normal controls (p<0.01). These findings paralleled with higher plasma levels of IL-1ß (p<0.05) and IL-18 (p<0.01) in those patients. Purified monocytes from SLE patients displayed a robust inflammatory response after LPS stimulation where Caspase-1, IL-1ß and IL-18 were highly expressed. Plasma levels of IL-18 were also significantly higher in SLE patients with active disease (p<0.05). In addition, the production of IL-18 was reduced by 3 fold when Caspase-1 inhibitor was added to the cultures. CONCLUSIONS: Monocytes from SLE patients exhibited increased inflammasome activation, characterized by high expression of Caspase-1, IL-1ß and IL-18. Caspase-1 specific inhibitor decreased inflammasome activation (in vitro) by suppressing the production of IL-18.

Patogenia de las manifestaciones neurológicas asociadas al SARS-CoV-2 / Pathogenesis of neurological manifestations associated to SARS-CoV-2

Introducción: Los coronavirus infectan al ser humano y pueden causar manifestaciones neurológicas en individuos susceptibles. Objetivo: Describir la patogenia de las manifestaciones neurológicas en pacientes con la COVID-19. Estrategia de búsqueda y criterios de selección: Se realizó una revisión bibliográfica empleando la bibliografía nacional e internacional actualizada. Se realizó la búsqueda en Google Académico, se consultaron artículos de libre acceso en las bases de datos Pubmed y SciELO, desde enero de 2014 hasta el 6 de mayo de 2020. Fueron seleccionados 51 artículos (6 en idioma español, 45 en inglés) y un libro de neuroinmunología. Se utilizaron los términos de búsqueda COVID-19, coronavirus, SARS-CoV-2,manifestaciones neurológicas, sistema nervioso, patogénesis, según el descriptor de Ciencias de la Salud (DeCS). Análisis e integración de la información: El SARS-CoV-2 entra al sistema nervioso por la vía linfática, hematógena, transináptica retrógada, por diseminación local a través del etmoides o por disfunción de la barrera hematoencefálica. La patogenia puede ser por la acción directa del virus o inmunomediada. En la pandemia de COVID-19 se reportan pacientes con manifestaciones neurológicas centrales, periféricas y musculoesqueléticas. Los síntomas más frecuentes son los trastornos del gusto, el olfato, cefaleas, mialgias y mareos. En las formas graves se reportan meningitis, encefalitis, síndrome de Guillain-Barré, ictus y encefalopatías. Conclusiones: El SARS-CoV-2 puede afectar al sistema nervioso central y periférico. Causa principalmente manifestaciones leves y transitorias, aunque pueden ocurrir complicaciones neurológicas. Los mecanismos patogénicos principales son el daño citopático directo o mecanismos indirectos debido a una respuesta inflamatoria(AU)

Introduction: Coronaviruses infect humans and may cause neurological manifestations in susceptible individuals. Objective: Describe the pathogenesis of neurological manifestations in patients with COVID-19. Search strategy and selection criteria: A review was conducted of national and international updated bibliography. The search was carried out in Google Scholar and open access papers were consulted in the databases PubMed and SciELO from January 2014 to 6 May 2020. A total 51 papers (6 in Spanish and 45 in English) and a book on neuroimmunology were selected. The search terms used were COVID-19, coronavirus, SARS-CoV-2, neurological manifestations, nervous system and pathogenesis, in compliance with the Health Sciences Descriptors (DeCS). Data analysis and integration: SARS-CoV-2 enters the nervous system by lymphatic, hematogenous, transynaptic, retrograde routes, by local dissemination through the ethmoid, or by dysfunction of the hematoencephalic barrier. Pathogenesis may be due to direct action by the virus or immunomediated. During the COVID-19 pandemic patients have been reported with central, peripheral and musculoskeletal neurological manifestations. The most common symptoms are taste and smell disorders, headache, myalgia and dizziness. Meningitis, encephalitis, Guillain-Barré syndrome, stroke and encephalopathies have been reported in severe forms of the disease. Conclusions: SARS-CoV-2 may affect the central and the peripheral nervous system. It mainly causes mild, transient manifestations, but neurological complications may also occur. The main pathogenic mechanisms are direct cytophatic damage or indirect mechanisms resulting from an inflammatory response(AU)

Ceratocystis fimbriata agente causal de la enfermedad de marchitez vascular de Tectona grandis L.f. (teca) en Ecuador / Ceratocystis fimbriata causative agent of vascular wilt disease of Tectona grandis L.f. (teak) in Ecuador

Tectona grandis L.f. es una especie forestal de madera dura que, a pesar de no ser nativa de América, su plasticidad de adaptación ha permitido que en Ecuador se establezcan plantaciones intensivas con fines de exportación. Una compleja enfermedad con características de marchitez vascular está matando miles de árboles de diferentes edades en el país. Se planteó conocer el agente fitopatógeno causante de la patogénesis y muerte de los árboles. Se aislaron los hongos Fusarium sp. y Ceratocystis fimbriata Ellis & Halst. desde árboles enfermos. A nivel de invernadero se plantearon los postulados de Koch, para el efecto 30 plantas de T. grandis de cuatro meses de edad por cada tratamiento, se inocularon con los microrganismos como se describe a continuación: T1= C. fimbriata, T2 = Fusarium sp., T3 = C. fimbriata + Fusarium sp., T4 = agar-agar (control). Se empleó un diseño completo al azar (DCA) y las plantas se evaluaron a los 45 días después de inoculadas. Los tratamientos C. fimbriata, y C. fimbriata + Fusarium sp., mostraron mayores volúmenes aparentes de necrosis, con 1.52 cm3 y 1.93 cm3, y plantas muertas por la infección durante el tiempo de evaluación, mientras que Fusarium sp. mostró baja o nula patogenicidad y comportamiento similar al control, con 0.27 cm3 y 0.16 cm3 respectivamente. Estos resultados sugieren que el agente causal de la enfermedad de marchitez vascular en T. grandis es C. fimbriata y sería el primer reporte del fitopatógeno atacando teca en Ecuador. (AU)

Tectona grandisL.f. it is a hardwood forest species, which despite not being native to America, its adaptive plasticity has allowed intensive plantations to be established for export purposes in Ecuador. A complex disease with characteristics of vascular wilt is killing thousands of trees of different ages in the country. It was proposed to know the phytopathogenic agent causing the pathogenesis and death of the trees. Fusarium sp. andCeratocystis fimbriata Ellis & Halst. were isolated from diseased trees. At the greenhouselevel, Koch's postulates were proposed, for the effect 30 four month old T. grandisplants for each treatment were inoculated with the microorganisms as described below: T1 = C. fimbriata, T2 = Fusariumsp ., T3 = C. fimbriata+ Fusariumsp., T4 = agar-agar (control). A complete randomized design (DCA) was used and the plants were evaluated 45 days after inoculation. The treatments C. fimbriata, and C. fimbriata+ Fusariumsp. showed higher apparent volumes of necrosis, with 1.52 cm3and 1.93 cm3, and plants killed by the infection during the evaluation time, while Fusariumsp. showed low or no pathogenicity and behavior similar to the control, with 0.27 cm3and 0.16 cm3respectively. These results suggest that the causative agent of vascular wilt disease in T. grandisis C. fimbriataand it would be the first report of phytopathogen attacking teak in Ecuador. (AU)

Melanosis coli: A comprehensive review.

Melanosis coli (MC) is a common condition characterized by a black or brown pigment deposited in the colorectal mucosa. It is a reversible condition that is influenced by many factors, such as living habits and bowel function. However, the epidemiology and etiology of MC are still unclear. Most studies show that there is a significant correlation between the use of anthraquinone laxatives and the occurrence of MC. At present, the mechanism of the apoptosis theory is widely recognized as regards the pathogenesis of MC. There is no specific clinical manifestation of MC, and its diagnosis is mainly based on a complimentary examination, such as endoscopic and histopathological tests. General treatment, such as changing living habits, is preferred, and medical or surgical treatment should not be considered in the absence of serious malignancy. The aim of this review is to systematically present and outline the concepts of the epidemiology, etiology, histopathology, pathogenesis, clinical manifestations, diagnosis and treatment of MC, in order to improve the understanding of this condition.

Tuberculosis-HIV Co-Infection: Progress and Challenges After Two Decades of Global Antiretroviral Treatment Roll-Out.

Despite wide antiretroviral scale-up during the past two decades resulting in declining new infections and mortality globally, HIV-associated tuberculosis remains as a major public health concern. Tuberculosis is the leading HIV-associated opportunistic infection and the main cause of death globally and, particularly, in resource-limited settings. Several challenges exist regarding diagnosis, global implementation of latent tuberculosis treatment, management of active tuberculosis, delivery of optimal patient-centered TB and HIV prevention and care in high burden countries. In this article we review the advances on pathogenesis, diagnosis, and treatment after nearly two decades of global roll-out of antiretroviral therapy and discuss the current challenges for the global control of tuberculosis-HIV co-infection.