Prediction and Potential Spatially Explicit Spread of COVID-19 in Mexico's Megacity North Periphery.

The novel COVID-19, detected in Wuhan, China, has reached almost every city across the globe, and researchers from many countries have used several epidemiologic models to describe the epidemic trends. In this context, it is also important to know the geographic extent of the infected population. Following this approach, a Gumpertz model was adapted with official data from the state of Hidalgo, Mexico, in order to estimate the people infected during this COVID-19 pandemic. We found, based on the adjusted data, the highest value in infected people according to official and theoretical data. Furthermore, using a geographical analysis based on geostatistical measures related to density of demographic and economic data, traffic level and geolocation, raster files were generated to estimate probability of coronavirus cases occurrence using the areas where the contagion may occur. We also distributed the maximum contagion obtained by the epidemic model, using these raster files, and a regression model to weight factors according their importance. Based on this estimated distribution, we found that most of the infected people were located in the southern border, a trend related to the economic strip in the southern part of Hidalgo State, associated with its vicinity to the Megacity of Mexico.

Acinetobacter baumannii Resistance: A Real Challenge for Clinicians.

Acinetobacter baumannii (named in honor of the American bacteriologists Paul and Linda Baumann) is a Gram-negative, multidrug-resistant (MDR) pathogen that causes nosocomial infections, especially in intensive care units (ICUs) and immunocompromised patients with central venous catheters. A. baumannii has developed a broad spectrum of antimicrobial resistance, associated with a higher mortality rate among infected patients compared with other non-baumannii species. In terms of clinical impact, resistant strains are associated with increases in both in-hospital length of stay and mortality. A. baumannii can cause a variety of infections; most involve the respiratory tract, especially ventilator-associated pneumonia, but bacteremia and skin wound infections have also been reported, the latter of which has been prominently observed in the context of war-related trauma. Cases of meningitis associated with A. baumannii have been documented. The most common risk factor for the acquisition of MDR A baumannii is previous antibiotic use, following by mechanical ventilation, length of ICU/hospital stay, severity of illness, and use of medical devices. Current efforts focus on addressing all the antimicrobial resistance mechanisms described in A. baumannii, with the objective of identifying the most promising therapeutic scheme. Bacteriophage- and artilysin-based therapeutic approaches have been described as effective, but further research into their clinical use is required.

Human Dendritic Cells: Ontogeny and Their Subsets in Health and Disease.

Dendritic cells (DCs) are a type of cells derived from bone marrow that represent 1% or less of the total hematopoietic cells of any lymphoid organ or of the total cell count of the blood or epithelia. Dendritic cells comprise a heterogeneous population of cells localized in different tissues where they act as sentinels continuously capturing antigens to present them to T cells. Dendritic cells are uniquely capable of attracting and activating naïve CD4⁺ and CD8⁺ T cells to initiate and modulate primary immune responses. They have the ability to coordinate tolerance or immunity depending on their activation status, which is why they are also considered as the orchestrating cells of the immune response. The purpose of this review is to provide a general overview of the current knowledge on ontogeny and subsets of human dendritic cells as well as their function and different biological roles.

Apoptosis: Activation and Inhibition in Health and Disease.

There are many types of cell death, each involving multiple and complex molecular events. Cell death can occur accidentally when exposed to extreme physical, chemical, or mechanical conditions, or it can also be regulated, which involves a genetically coded complex machinery to carry out the process. Apoptosis is an example of the latter. Apoptotic cell death can be triggered through different intracellular signalling pathways that lead to morphological changes and eventually cell death. This is a normal and biological process carried out during maturation, remodelling, growth, and development in tissues. To maintain tissue homeostasis, regulatory, and inhibitory mechanisms must control apoptosis. Paradoxically, these same pathways are utilized during infection by distinct intracellular microorganisms to evade recognition by the immune system and therefore survive, reproduce and develop. In cancer, neoplastic cells inhibit apoptosis, thus allowing their survival and increasing their capability to invade different tissues and organs. The purpose of this work is to review the generalities of the molecular mechanisms and signalling pathways involved in apoptosis induction and inhibition. Additionally, we compile the current evidence of apoptosis modulation during cancer and Leishmania infection as a model of apoptosis regulation by an intracellular microorganism.

Metahemoglobinemia severa secundaria a sobredosis de dapsona, reporte de caso / Severe metahemoglobinemia associated with dapsone overdosis. Case report / Metemoglobinemia severa secundária à sobredosagem de Dapsona, relato de um caso

Resumen: La metahemoglobinemia es una entidad clínica causada por la oxidación de la hemoglobina (Hb), específicamente del grupo hemo, transforma el hierro de un estado ferroso (Fe2+) a férrico (Fe3+++), dando como resultado la metahemoglobina (MetHb), la cual no es capaz de realizar enlaces con el oxígeno (O2) y por lo tanto no puede trasportarlo, condicionando una disminución en la oxigenación tisular. La Hb puede oxidarse debido a alteraciones genéticas de expresión variable o más frecuentemente por efecto adverso de sustancias exógenas, destacando fármacos como la dapsona. Se describe el cuadro clínico, diagnóstico y tratamiento de una paciente con metahemoglobinemia adquirida por sobredosis de dapsona.

Abstract: Methemoglobinemia is a clinical entity caused by oxidation of hemoglobin (Hb) specifically heme, transforming iron from a ferrous state (Fe2+) to a ferric state (Fe3+++), resulting in methemoglobin (MetHb), which is not capable of bonding with oxygen (O2), and therefore cannot transport it, conditioning tissue irrigation. Hb may oxidize due to variable expression genetic abnormalities expression, or more frequently, as an adverse effect related to exogenous substances, such as dapsone. This work describes the clinical picture, diagnosis and treatment of a patient with metahemoglobinemia-acquired secondary to dapsone overdose.

Resumo: A metemoglobinemia é uma entidade clínica causada pela oxidação da hemoglobina (Hb), especificamente do grupo heme, transformando o ferro de um estado ferroso (Fe2+) para um estado férrico (Fe3+++), dando como resultado a Meta-hemoglobina (MetHb), que não é capaz de fazer ligações com o oxigênio (O2) e, portanto, não pode transportá-lo, condicionando a diminuição na oxigenação tissular. A Hb pode oxidar-se devido a alterações genéticas de expressão variável, ou mais freqüentemente devido ao efeito adverso de substâncias exógenas, destacando drogas como a Dapsona. Descrevemos o quadro clínico, diagnóstico e tratamento de um paciente com metemoglobinemia adquirida por sobredosagem de dapsona.