RESUMEN

Oropouche fever is a zoonotic dengue-like syndrome caused by Oropouche virus. In August-September 2020, dengue-like syndrome developed in 41 patients in a remote rainforest village in French Guiana. By PCR or microneutralization, 23 (82.1%) of 28 tested patients were positive for Oropouche virus, documenting its emergence in French Guiana.

Asunto(s)

RESUMEN

PURPOSE OF REVIEW: In this review, we report on the state of knowledge about human Q fever in Brazil and on the Guiana Shield, an Amazonian region located in northeastern South America. There is a contrast between French Guiana, where the incidence of this disease is the highest in the world, and other countries where this disease is practically non-existent. RECENT FINDINGS: Recent findings are essentially in French Guiana where a unique strain MST17 has been identified; it is probably more virulent than those usually found with a particularly marked pulmonary tropism, a mysterious animal reservoir, a geographical distribution that raises questions. SUMMARY: Q fever is a bacterial zoonosis due to Coxiella burnetii that has been reported worldwide. On the Guiana Shield, a region mostly covered by Amazonian forest, which encompasses the Venezuelan State of Bolivar, Guyana, Suriname, French Guiana, and the Brazilian State of Amapá, the situation is very heterogeneous. While French Guiana is the region reporting the highest incidence of this disease in the world, with a single infecting clone (MST 117) and a unique epidemiological cycle, it has hardly ever been reported in other countries in the region. This absence of cases raises many questions and is probably due to massive under-diagnosis. Studies should estimate comprehensively the true burden of this disease in the region.

RESUMEN

INTRODUCTION: Alzheimer's disease (AD) is the leading cause of dementia worldwide. Despite the extensive research, its pathophysiology remains largely unelucidated. Currently, more attention is being given to the disease's vascular and inflammatory aspects. In this context, the renin-angiotensin system (RAS) emerges as a credible player in AD pathogenesis. The RAS has multiple physiological functions, conducted by its two opposing axes: the classical, led by Angiotensin II (Ang II), and the alternative, driven by Angiotensin-(1-7) [Ang-(1-7)]. These peptides were shown to interact with AD pathology in animal studies, but evidence from humans is scarce. Only 20 studies dosed RAS molecules in AD patients' bloodstream, none of which assessed both axes simultaneously. Therefore, we conducted a cross-sectional, case-control exploratory study to compare plasma levels of Ang II and Ang-(1-7) in AD patients vs. age-matched controls. Within each group, we searched for correlations between RAS biomarkers and measures from magnetic resonance imaging (MRI). METHODS: We evaluated patients with AD (n = 14) and aged-matched controls (n = 14). Plasma Ang II and Ang-(1-7) were dosed using ELISA. Brain MRI was performed in a 3 Tesla scan, and a three-dimensional T1-weighted volumetric sequence was obtained. Images were then processed by FreeSurfer to calculate: (1) white matter hypointensities (WMH) volume; (2) volumes of hippocampus, medial temporal cortex, and precuneus. Statistical analyses used non-parametrical tests (Mann-Whitney and Spearman). RESULTS: Ang-(1-7) levels in plasma were significantly lower in the AD patients than in controls [median (25th-75th percentiles)]: AD [101.5 (62.43-126.4)] vs. controls [209.3 (72-419.1)], p = 0.014. There was no significant difference in circulating Ang II. In the AD patients, but not in controls, there was a positive and significant correlation between Ang-(1-7) values and WMH volumes (Spearman's rho = 0.56, p = 0.038). Ang-(1-7) did not correlate with cortical volumes in AD or in controls. Ang II did not correlate with any MRI variable in none of the groups. CONCLUSION: If confirmed, our results strengthen the hypothesis that RAS alternative axis is downregulated in AD, and points to a possible interaction between Ang-(1-7) and cerebrovascular lesions in AD.

RESUMEN

The emergence of SARS-CoV-2/human/Wuhan/X1/2019, a virus belonging to the species Severe acute respiratory syndrome-related coronavirus, and the recognition of Coronavirus Disease 2019 (COVID-19) as a pandemic have highly increased the scientific research regarding the pathogenesis of COVID-19. The Renin Angiotensin System (RAS) seems to be involved in COVID-19 natural course, since studies suggest the membrane-bound Angiotensin-converting enzyme 2 (ACE2) works as SARS-CoV-2 cellular receptor. Besides the efforts of the scientific community to understand the virus' molecular interactions with human cells, few studies summarize what has been so far discovered about SARS-CoV-2 signaling mechanisms and its interactions with RAS molecules. This review aims to discuss possible SARS-CoV-2 intracellular signaling pathways, cell entry mechanism and the possible consequences of the interaction with RAS components, including Angiotensin II (Ang II), Angiotensin-(1-7) [Ang-(1-7)], Angiotensin-converting enzyme (ACE), ACE2, Angiotensin II receptor type-1 (AT1), and Mas Receptor. We also discuss ongoing clinical trials and treatment based on RAS cascade intervention. Data were obtained independently by the two authors who carried out a search in the PubMed, Embase, LILACS, Cochrane, Scopus, SciELO and the National Institute of Health databases using Medical Subject Heading terms as "SARS-CoV-2," "COVID-19," "Renin Angiotensin System," "ACE2," "Angiotensin II," "Angiotensin-(1-7)," and "AT1 receptor." Similarly to other members of Coronaviridae family, the molecular interactions between the pathogen and the membrane-bound ACE2 are based on the cleavage of the spike glycoprotein (S) in two subunits. Following the binding of the S1 receptor-binding domain (RBD) to ACE2, transmembrane protease/serine subfamily 2 (TMPRSS2) cleaves the S2 domain to facilitate membrane fusion. It is very likely that SARS-CoV-2 cell entry results in downregulation of membrane-bound ACE2, an enzyme that converts Ang II into Ang-(1-7). This mechanism can result in lung injury and vasoconstriction. In addition, Ang II activates pro-inflammatory cascades when binding to the AT1 Receptor. On the other hand, Ang-(1-7) promotes anti-inflammatory effects through its interactions with the Mas Receptor. These molecules might be possible therapeutic targets for treating COVID-19. Thus, the understanding of SARS-CoV-2 intracellular pathways and interactions with the RAS may clarify COVID-19 physiopathology and open perspectives for new treatments and strategies.

RESUMEN

The emergency of SARS-CoV-2 in China started a novel challenge to the scientific community. As the virus turns pandemic, scientists try to map the cellular mechanisms and pathways of SARS-CoV-2 related to the pathogenesis of Coronavirus Disease 2019 (Covid-19). After transmembrane angiotensin-converting enzyme 2 (ACE2) has been found to be SARS-CoV-2 receptor, we hypothesized an immune-hematological mechanism for Covid-19 based on renin-angiotensin system (RAS) imbalance to explain clinical, laboratory and imaging findings on disease course. We believe that exaggerated activation of ACE/Angiotensin II (Ang II)/Angiotensin Type 1 (AT1) receptor RAS axis in line with reduction of ACE2/Angiotensin-(1-7)/Mas receptor may exert a pivotal role in the pathogenesis of Covid-19. In this perspective, we discuss potential mechanisms and evidence on this hypothesis.

Asunto(s)

Asunto(s)

Asunto(s)

RESUMEN

Ultrasonography performed by non-radiologist specialists is a tool that contributes to the diagnosis and monitoring of neurocritical patients. It is a non-invasive, low-cost, accurate and fast method that helps improve safety and timeliness in settings where prompt decision-making is imperative, such as in the operating room, critical care units or the emergency room. The objective is to conduct a narrative review, presenting ultrasound applications focused on the central nervous system that may be useful in neuroanaesthesia and neurocritical care. A search was performed of related terms on databases in the medical literature. Relevant papers where selected and reviewed to perform a non-systematic review focusing on the visualization of the midline and lateral ventricles, the measurement of the optic nerve sheath as a surrogate marker of intracranial hypertension, and the use of colour Doppler for visualizing the middle cerebral artery. It is expected that the use of ultrasound examination of the central nervous system will continue to evolve given its advantages, good correlation with studies considered as the gold standard, and the growing availability of the device. Advancements in this field are expected to improve timeliness and provide objective guidance for decision-making. We recognize the importance of developing skills in the use of this method of exploration in those services where it is required.

La ultrasonografía realizada por especialistas no radiólogos es una herramienta que contribuye al diagnóstico y monitoreo de los pacientes neurocríticos. Adicionalmente es económica, precisa, no invasiva y rápida, lo que mejora la seguridad y oportunidad en escenarios donde la toma inmediata de decisiones es imperativa tales como salas de cirugía, unidades de cuidado crítico o servicios de urgencias. El objetivo es realizar una revisión narrativa presentando las aplicaciones ultrasonográficas enfocadas al sistema nervioso central (SNC) que pueden ser útiles en neuroanestesia y cuidado neurocrítico. Se realizó una búsqueda en bases de datos de los términos relacionados en la literatura médica. Se seleccionaron y revisaron artículos de relevancia para realizar una revisión no sistemática que se centró en la visualización de la línea media, ventrículos laterales, medición de la vaina del nervio óptico como subrogador de hipertensión endocraneana y en la visualización de la arteria cerebral media a través de doppler color. Se prevé que continuarán los avances en la exploración ultrasonográfica del SNC debido a sus ventajas, la buena correlación con los estudios considerados como estándar de oro y la creciente disponibilidad de ecógrafo. Es de esperar que se mejore la oportunidad y ayude a dirigir la toma de decisiones objetivamente. Se reconoce la importancia del desarrollo de habilidades en el manejo de este método de exploración para aplicarlo en los servicios donde sea requerido.

Asunto(s)

RESUMEN

Background. Leprosy is a chronic infectious disease caused by the intracellular acid-fast bacilli Mycobacterium leprae; it has been determined that genetic factors of the host play an important role in the disease susceptibility. Thus, in this case-control study, we evaluated the possible association between the IL-17A G-197A (rs227593) and IL-17F A7488G (His161Arg, rs763780) gene SNPs and susceptibility to leprosy disease in Mexican population. Methods. Seventy-five leprosy patients and sixty-nine control subjects were included. Both SNPs were genotyped with the polymerase chain reaction-restriction fragment length polymorphism technique. Results. We found nonsignificant differences in genotype and allele frequencies related to IL-17A G-197A (rs227593) and IL-17F A7488G (His161Arg, rs763780) gene SNPs in MB as well as subclinical forms of leprosy disease versus healthy individuals. Conclusions. Since the sample size is not large enough, it is difficult to sustain an association of susceptibility to leprosy with genotypes or allele frequencies of IL-17A G-197A (rs227593) and IL-17F A7488G (His161Arg, rs763780), suggesting that IL-17 polymorphisms have no significant role in the genetic susceptibility to development of this disease in the Mexican Mestizo population.

RESUMEN

El uso de coberturas vivas de leguminosas en plantaciones citrícolas constituye una alternativa viable para el mejoramiento de las propiedades de los suelos, siempre que ellas se manejan adecuadamente en estas áreas. En la universidad de Ciego de Ávila, Cuba se viene trabajando en la evaluación del efecto de coberturas vivas de leguminosas en plantaciones citrícolas en producción, con el objetivo de evaluar el efecto que ejerce la cobertura de leguminosa sobre algunas propiedades del suelo. El trabajo se realizó durante cuatro años (2001-2005) en una plantación de naranja Valencia Late ( Citrus sinensis L. Osbeck) en producción de 22 años, con marco de plantación de 8 X 4 m, plantada sobre un suelo Ferralítico Rojo típico, perteneciente a la CPA ¨José Martí¨ , en Ciego de Ávila. Se empleó un diseño de bloque al azar, con tres tratamientos: con cobertura de Teramnus labialis (T1) con una dosis de siembra 2.5 kg.ha-1 a voleo, cobertura natural (T2) y suelo desnudo (T3). Se determinaron las propiedades estructuro-funcionales del suelo, la composición de macroagregados expresadas en el coeficiente de estructura y el porcentaje de agregados estables en agua, densidad del suelo, humedad y la porosidad. Los incrementos en los contenidos de humedad, el volumen específico total de poros y de aire, el coeficiente de estructura, así como el porcentaje de agregados estables al agua, en el

The use of leguminous cover crops in citrus orchards constitutes a viable alternative for the improvement of soil properties, whenever they are appropriately managed. In Ciego de Avila University, Cuba, it was evaluated the effect of a leguminous cover crop on some properties of an orchard soil. The work was carried out during four years in an orange plantation of Valencia late (Citrus sinensis L. Osbeck) in a 22 years-old orchard, with a plantation frame of 8 X 4 m, planted on a typical red Ferralitic soil, belonging to the CPA ¨José Martí¨, in Ciego de Avila. It was used a random block design with three treatments: one with covering of Teramnus labialis (T1), one with expontaneous vegetation (T2) and the third with no vegetation (T3). The functional structure properties of the soil were determined, and also the composition of macroaggregates expressed in the structure coefficient and the percentage of stable added in water, soil density, humidity and porosity. The increments in the humidity of the soil, the specific volume of pores and air, the structure coefficient, as well as the percentage of stable added in water, in the soil where the covering of Teramnus labialis was stablished, show the efficiency of cover crops in these citrus orchards.

El uso de coberturas vivas de leguminosas en plantaciones citrícolas constituye una alternativa viable para el mejoramiento de las propiedades de los suelos, siempre que ellas se manejan adecuadamente en estas áreas. En la universidad de Ciego de Ávila, Cuba se viene trabajando en la evaluación del efecto de coberturas vivas de leguminosas en plantaciones citrícolas en producción, con el objetivo de evaluar el efecto que ejerce la cobertura de leguminosa sobre algunas propiedades del suelo. El trabajo se realizó durante cuatro años (2001-2005) en una plantación de naranja Valencia Late ( Citrus sinensis L. Osbeck) en producción de 22 años, con marco de plantación de 8 X 4 m, plantada sobre un suelo Ferralítico Rojo típico, perteneciente a la CPA ¨José Martí¨ , en Ciego de Ávila. Se empleó un diseño de bloque al azar, con tres tratamientos: con cobertura de Teramnus labialis (T1) con una dosis de siembra 2.5 kg.ha-1 a voleo, cobertura natural (T2) y suelo desnudo (T3). Se determinaron las propiedades estructuro-funcionales del suelo, la composición de macroagregados expresadas en el coeficiente de estructura y el porcentaje de agregados estables en agua, densidad del suelo, humedad y la porosidad. Los incrementos en los contenidos de humedad, el volumen específico total de poros y de aire, el coeficiente de estructura, así como el porcentaje de agregados estables al agua, en el

RESUMEN

El uso de coberturas vivas de leguminosas en plantaciones citrícolas constituye una alternativa viable para el mejoramiento de las propiedades de los suelos, siempre que ellas se manejan adecuadamente en estas áreas. En la universidad de Ciego de Ávila, Cuba se viene trabajando en la evaluación del efecto de coberturas vivas de leguminosas en plantaciones citrícolas en producción, con el objetivo de evaluar el efecto que ejerce la cobertura de leguminosa sobre algunas propiedades del suelo. El trabajo se realizó durante cuatro años (2001-2005) en una plantación de naranja Valencia Late ( Citrus sinensis L. Osbeck) en producción de 22 años, con marco de plantación de 8 X 4 m, plantada sobre un suelo Ferralítico Rojo típico, perteneciente a la CPA ¨José Martí¨ , en Ciego de Ávila. Se empleó un diseño de bloque al azar, con tres tratamientos: con cobertura de Teramnus labialis (T1) con una dosis de siembra 2.5 kg.ha-1 a voleo, cobertura natural (T2) y suelo desnudo (T3). Se determinaron las propiedades estructuro-funcionales del suelo, la composición de macroagregados expresadas en el coeficiente de estructura y el porcentaje de agregados estables en agua, densidad del suelo, humedad y la porosidad. Los incrementos en los contenidos de humedad, el volumen específico total de poros y de aire, el coeficiente de estructura, así como el porcentaje de agregados estables al agua, en el

The use of leguminous cover crops in citrus orchards constitutes a viable alternative for the improvement of soil properties, whenever they are appropriately managed. In Ciego de Avila University, Cuba, it was evaluated the effect of a leguminous cover crop on some properties of an orchard soil. The work was carried out during four years in an orange plantation of Valencia late (Citrus sinensis L. Osbeck) in a 22 years-old orchard, with a plantation frame of 8 X 4 m, planted on a typical red Ferralitic soil, belonging to the CPA ¨José Martí¨, in Ciego de Avila. It was used a random block design with three treatments: one with covering of Teramnus labialis (T1), one with expontaneous vegetation (T2) and the third with no vegetation (T3). The functional structure properties of the soil were determined, and also the composition of macroaggregates expressed in the structure coefficient and the percentage of stable added in water, soil density, humidity and porosity. The increments in the humidity of the soil, the specific volume of pores and air, the structure coefficient, as well as the percentage of stable added in water, in the soil where the covering of Teramnus labialis was stablished, show the efficiency of cover crops in these citrus orchards.

El uso de coberturas vivas de leguminosas en plantaciones citrícolas constituye una alternativa viable para el mejoramiento de las propiedades de los suelos, siempre que ellas se manejan adecuadamente en estas áreas. En la universidad de Ciego de Ávila, Cuba se viene trabajando en la evaluación del efecto de coberturas vivas de leguminosas en plantaciones citrícolas en producción, con el objetivo de evaluar el efecto que ejerce la cobertura de leguminosa sobre algunas propiedades del suelo. El trabajo se realizó durante cuatro años (2001-2005) en una plantación de naranja Valencia Late ( Citrus sinensis L. Osbeck) en producción de 22 años, con marco de plantación de 8 X 4 m, plantada sobre un suelo Ferralítico Rojo típico, perteneciente a la CPA ¨José Martí¨ , en Ciego de Ávila. Se empleó un diseño de bloque al azar, con tres tratamientos: con cobertura de Teramnus labialis (T1) con una dosis de siembra 2.5 kg.ha-1 a voleo, cobertura natural (T2) y suelo desnudo (T3). Se determinaron las propiedades estructuro-funcionales del suelo, la composición de macroagregados expresadas en el coeficiente de estructura y el porcentaje de agregados estables en agua, densidad del suelo, humedad y la porosidad. Los incrementos en los contenidos de humedad, el volumen específico total de poros y de aire, el coeficiente de estructura, así como el porcentaje de agregados estables al agua, en el