A review on the influence of rapid maxillary expansion and mandibular advancement for treating obstructive sleep apnea in children.

This article reviews the orthodontic alternatives for treating pediatric obstructive sleep apnea (OSA). OSA is a multifactorial disease that impairs craniofacial growth and the general health of a developing child and negatively worsens their quality of life. Therefore, it is important to timely diagnose and treat OSA to avoid the progress of the disease, which could otherwise lead to systemic, neurocognitive and social consequences in the patients. In the transverse direction, compression of the maxilla could decrease the diameter of the upper airways and reduce airflow. In the sagittal direction, a retrognathic mandible positioned more posteriorly to the tongue could reduce the available upper airway space and decrease airflow during sleep. Orthopedic treatments for mild to moderate OSA include maxillary expansion using rapid maxillary expansion devices and mandibular advancement using mandibular advancement appliances, which are treatment options only when skeletal discrepancies exist and should be applied after appropriate individual diagnosis for each orthodontic patient. Currently, limited evidence suggests that these therapies could reduce the signs and symptoms and the apnea-hypopnea index (AHI) of OSA.

Vimentin as a Marker of Early Differentiating, Highly Motile Corneal Epithelial Cells.

Vimentin (Vim), a cytoskeletal intermediate filament, is part of a naturally occurring reversible program, the Epithelial-Mesenchymal Transition (EMT), which converts epithelial cells into mesenchymal-like derivatives. Based on previous results showing that epithelial cells co-express Vim and keratin (Krt) as part of a cytoskeletal network which confers them a highly motile phenotype, we explored the role of Vim in rabbit corneal epithelial cells or RCE1(5T5) cells, an established model of corneal epithelial differentiation. Vim and keratin filaments were co-expressed in cells localized at the proliferative/migratory rim of the growing colonies, but not in basal cells from the center of the colonies nor at suprabasal cell layers. Flow cytometry and qPCR demonstrated that there was a decrease in Krt+ /Vim+ cell number and ΔNp63α expression when cells reached confluence and formed a 4-5 layered epithelium, while there was a concomitant increase of both Pax-6 expression and Krt+ /Vim- cells. Inhibition of cell proliferation with mitomycin C did not modify cell motility nor the expression of Vim. We studied the distribution and expression of α6 integrin, a protein also involved in cell migration. The results demonstrated that α6 integrin had a distribution which was, in part, co-linear with Vim at the proliferative/migratory rim of cell colonies, suggesting an indirect interaction between these proteins. Immunoprecipitation and immunostaining assays indicated that plectin might be mediating such interaction. These data suggest that Vim expression in corneal epithelium is found in a cell population composed of highly motile cells with a Vim+ /Krt+ /ΔNp63α+ /Pax-6low /α6 integrin+ phenotype. J. Cell. Physiol. 232: 818-830, 2017. © 2016 Wiley Periodicals, Inc.

Competition for iron shapes metabolic antagonism between Bacillus subtilis and Pseudomonas marginalis.

Siderophores have long been implicated in sociomicrobiology as determinants of bacterial interrelations. For plant-associated genera, like Bacillus and Pseudomonas, siderophores are well known for their biocontrol functions. Here, we explored the functional role of the Bacillus subtilis siderophore bacillibactin (BB) in an antagonistic interaction with Pseudomonas marginalis. The presence of BB strongly influenced the outcome of the interaction in an iron-dependent manner. The BB producer B. subtilis restricts colony spreading of P. marginalis by repressing the transcription of histidine kinase-encoding gene gacS, thereby abolishing production of secondary metabolites such as pyoverdine and viscosin. By contrast, lack of BB restricted B. subtilis colony growth. To explore the specificity of the antagonism, we cocultured B. subtilis with a collection of fluorescent Pseudomonas spp. and found that the Bacillus-Pseudomonas interaction is conserved, expanding our understanding of the interplay between two of the most well-studied genera of soil bacteria.

Risk factors for acute kidney injury in patients hospitalized with COVID-19.

INTRODUCTION: Acute kidney injury (AKI) occurs frequently in COVID-19 patients and is associated with greater morbidity and mortality. Knowing the risks of AKI allows for identification, prevention, and timely treatment. This study aimed to identify the risk factors associated with AKI in hospitalized patients. METHODS: A descriptive, retrospective, cross-sectional, and analytical component study of adult patients hospitalized with COVID-19 from March 1 to December 31, 2020 was carried out. AKI was defined by the creatinine criteria of the KDIGO-AKI guidelines. Information, regarding risk factors, was obtained from electronic medical records. RESULTS: Out of the 934 patients, 42.93% developed AKI, 60.59% KDIGO-1, and 9.9% required renal replacement therapy. Patients with AKI had longer hospital stay, higher mortality, and required more intensive care unit (ICU) admission, mechanical ventilation, and vasopressor support. Multivariate analysis showed that age (OR 1.03; 95% CI 1.02-1.04), male sex (OR 2.13; 95% CI 1.49-3.04), diabetes mellitus (DM) (OR 1.55; 95% CI 1.04-2.32), chronic kidney disease (CKD) (OR 2.07; 95% CI 1.06-4.04), C-reactive protein (CRP) (OR 1.02; 95% CI 1.00-1.03), ICU admission (OR 1.81; 95% CI 1.04-3.16), and vasopressor support (OR 7.46; 95% CI 3.34-16.64) were risk factors for AKI, and that bicarbonate (OR 0.89; 95% CI 0.84-0.94) and partial pressure arterial oxygen/inspired oxygen fraction index (OR 0.99; 95% CI 0.98-0.99) could be protective factors. CONCLUSIONS: A high frequency of AKI was documented in COVID-19 patients, with several predictors: age, male sex, DM, CKD, CRP, ICU admission, and vasopressor support. AKI occurred more frequently in patients with higher disease severity and was associated with higher mortality and worse outcomes.

The Lys20 homocitrate synthase isoform exerts most of the flux control over the lysine synthesis pathway in Saccharomyces cerevisiae.

In Saccharomyces cerevisiae, the first committed step in the lysine (Lys) biosynthetic pathway is catalysed by the Lys20 and Lys21 homocitrate synthase (HCS) isoforms. Overexpression of Lys20 resulted in eightfold increased Lys, as well as 2-oxoglutarate pools, which were not attained by overexpressing Lys21 or other pathway enzymes (Lys1, Lys9 or Lys12). A metabolic control analysis-based strategy, by gradually and individually manipulating the Lys20 and Lys21 activities demonstrated that the cooperative and strongly feedback-inhibited Lys21 isoform exerted low control of the pathway flux whereas most of the control resided on the non-cooperative and weakly feedback-inhibited Lys20 isoform. Therefore, the higher control of Lys20 over the Lys flux represents an exception to the dogma of higher pathway control by the strongest feedback-inhibited enzyme and points out to multi-site engineering (HCS isoforms and supply of precursors) to increase Lys synthesis.

Polymerized-type I collagen induces upregulation of Foxp3-expressing CD4 regulatory T cells and downregulation of IL-17-producing CD4⁺ T cells (Th17) cells in collagen-induced arthritis.

Previous studies showed that polymerized-type I collagen (polymerized collagen) exhibits potent immunoregulatory properties. This work evaluated the effect of intramuscular administration of polymerized collagen in early and established collagen-induced arthritis (CIA) in mice and analyzed changes in Th subsets following therapy. Incidence of CIA was of 100% in mice challenged with type II collagen. Clinimorphometric analysis showed a downregulation of inflammation after administration of all treatments (P < 0.05). Histological analysis showed that the CIA-mice group had extensive bone erosion, pannus and severe focal inflammatory infiltrates. In contrast, there was a remarkable reduction in the severity of arthritis in mice under polymerized collagen, methotrexate or methotrexate/polymerized collagen treatment. Polymerized Collagen but not methotrexate induced tissue joint regeneration. Polymerized Collagen and methotrexate/polymerized collagen but not methotrexate alone induces downregulation of CD4(+)/IL17A(+) T cells and upregulation of Tregs and CD4(+)/IFN-γ(+) T cells. Thus, Polymerized Collagen could be an effective therapeutic agent in early and established rheumatoid arthritis by exerting downregulation of autoimmune inflammation.

Using a label-free proteomics method to identify differentially abundant proteins in closely related hypo- and hypervirulent clinical Mycobacterium tuberculosis Beijing isolates.

Although the genome of the Mycobacterium tuberculosis H37Rv laboratory strain has been available for over 10 years, it is only recently that genomic information from clinical isolates has been used to generate the hypothesis of virulence differences between different strains. In addition, the relationship between strains displaying differing virulence in an epidemiological setting and their behavior in animal models has received little attention. The potential causes for variation in virulence between strains, as determined by differential protein expression, have similarly been a neglected area of investigation. In this study, we used a label-free quantitative proteomics approach to estimate differences in protein abundance between two closely related Beijing genotypes that have been shown to be hyper- and hypovirulent on the basis of both epidemiological and mouse model studies. We were able to identify a total of 1668 proteins from both samples, and protein abundance calculations revealed that 48 proteins were over-represented in the hypovirulent isolate, whereas 53 were over-represented in the hypervirulent. Functional classification of these results shows that molecules of cell wall organization and DNA transcription regulatory proteins may have a critical influence in defining the level of virulence. The reduction in the presence of ESAT-6, other Esx-like proteins, and FbpD (MPT51) in the hypervirulent strain indicates that changes in the repertoire of highly immunogenic proteins can be a defensive process undertaken by the virulent cell. In addition, most of the previously well characterized gene targets related to virulence were found to be similarly expressed in our model. Our data support the use of proteomics as a complementary tool for genomic comparisons to understand the biology of M. tuberculosis virulence.

Causes of erythrocytosis and its impact as a risk factor for thrombosis according to etiology: experience in a referral center in Mexico City.

BACKGROUND: Thrombotic events are well documented in primary erythrocytosis, but it is uncertain if secondary etiologies increase the risk of thrombosis. This study aimed to determine the causes of erythrocytosis and to identify its impact as a risk factor for thrombosis. METHODS: Data were obtained from patients with erythrocytosis between 2000 and 2017 at a referral hospital in Mexico City. Erythrocytosis was defined according to the 2016 WHO classification. Time to thrombosis, major bleeding, or death were compared among groups of patients defined by the etiology of erythrocytosis using a Cox regression model, adjusting for cardiovascular risk factors. RESULTS: In total, 330 patients with erythrocytosis were studied. The main etiologies of erythrocytosis were obstructive sleep apnea (OSA) in 29%, polycythemia vera (PV) in 18%, and chronic lung disease (CLD) in 9.4% of the patients. The incidence rate of thrombosis was significantly higher in patients with PV and CLD than that in patients with OSA (incidence rates of 4.51 and 6.24 vs. 1.46 cases per 100 person-years, P=0.009), as well as the mortality rate (mortality rates of 2.72 and 2.43 vs. 0.17 cases per 100 person-years, P =0.003). CONCLUSION: The risk of thrombosis in CLD with erythrocytosis was comparable to that in patients with PV. Further larger-scale studies are needed to confirm these findings and evaluate the benefits of preventive management of COPD with erythrocytosis similar to PV.

First insights into the genetic diversity of Mycobacterium tuberculosis isolates from HIV-infected Mexican patients and mutations causing multidrug resistance.

BACKGROUND: The prevalence of infections with Mycobacterium tuberculosis (MTb) and nontuberculous mycobacteria (NTM) species in HIV-infected patients in Mexico is unknown. The aims of this study were to determine the frequency of MTb and NTM species in HIV-infected patients from Mexico City, to evaluate the genotypic diversity of the Mycobacterium tuberculosis complex strains, to determine their drug resistance profiles by colorimetric microplate Alamar Blue assay (MABA), and finally, to detect mutations present in katG, rpoB and inhA genes, resulting in isoniazid (INH) and rifampin (RIF) resistance. RESULTS: Of the 67 mycobacterial strains isolated, 48 were identified as MTb, 9 as M. bovis, 9 as M. avium and 1 as M. intracellulare. IS6110-RFLP of 48 MTb strains showed 27 profiles. Spoligotyping of the 48 MTb strains yielded 21 patterns, and 9 M. bovis strains produced 7 patterns. Eleven new spoligotypes patterns were found. A total of 40 patterns were produced from the 48 MTb strains when MIRU-VNTR was performed. Nineteen (39.6%) MTb strains were resistant to one or more drugs. One (2.1%) multidrug-resistant (MDR) strain was identified. A novel mutation was identified in a RIF-resistant strain, GAG --> TCG (Glu --> Ser) at codon 469 of rpoB gene. CONCLUSIONS: This is the first molecular analysis of mycobacteria isolated from HIV-infected patients in Mexico, which describe the prevalence of different mycobacterial species in this population. A high genetic diversity of MTb strains was identified. New spoligotypes and MIRU-VNTR patterns as well as a novel mutation associated to RIF-resistance were found. This information will facilitate the tracking of different mycobacterial species in HIV-infected individuals, and monitoring the spread of these microorganisms, leading to more appropriate measures for tuberculosis control.

Induction of a protective response with an IgA monoclonal antibody against Mycobacterium tuberculosis 16kDa protein in a model of progressive pulmonary infection.

Mycobacterium tuberculosis is a facultative intracellular pathogen for which cell-mediated immunity is considered the major component of the immune response. For many decades, the prevailing scientific view has been the antibodies have little or no role in modifying the course of M. tuberculosis infection. In recent years, several studies have challenged this dogma, and there is a body of evidence that supports a role of antibodies against M. tuberculosis. In the present work, we evaluated the protective activity of two monoclonal antibodies (TBA61 and TBA84). Here, we chose the intratracheal model of pulmonary infection to evaluate bacterial load and morphometric and histological changes in the lungs of treated mice. Data obtained revealed the reduction of bacterial load and milder morphometric and histopathological changes in mice treated with TBA61 at 21 days post-infection with M. tuberculosis H37Rv compared to those treated with TBA84 and control mice. These results allow continuing exploring the potential use of monoclonal antibodies as prophylactic and therapeutic agents against intracellular pathogens such as M. tuberculosis.

Risk factors for acute kidney injury in patients hospitalized with COVID-19 / Fatores de risco para lesão renal aguda em pacientes hospitalizados com COVID-19

Abstract Introduction: Acute kidney injury (AKI) occurs frequently in COVID-19 patients and is associated with greater morbidity and mortality. Knowing the risks of AKI allows for identification, prevention, and timely treatment. This study aimed to identify the risk factors associated with AKI in hospitalized patients. Methods: A descriptive, retrospective, cross-sectional, and analytical component study of adult patients hospitalized with COVID-19 from March 1 to December 31, 2020 was carried out. AKI was defined by the creatinine criteria of the KDIGO-AKI guidelines. Information, regarding risk factors, was obtained from electronic medical records. Results: Out of the 934 patients, 42.93% developed AKI, 60.59% KDIGO-1, and 9.9% required renal replacement therapy. Patients with AKI had longer hospital stay, higher mortality, and required more intensive care unit (ICU) admission, mechanical ventilation, and vasopressor support. Multivariate analysis showed that age (OR 1.03; 95% CI 1.02-1.04), male sex (OR 2.13; 95% CI 1.49-3.04), diabetes mellitus (DM) (OR 1.55; 95% CI 1.04-2.32), chronic kidney disease (CKD) (OR 2.07; 95% CI 1.06-4.04), C-reactive protein (CRP) (OR 1.02; 95% CI 1.00-1.03), ICU admission (OR 1.81; 95% CI 1.04-3.16), and vasopressor support (OR 7.46; 95% CI 3.34-16.64) were risk factors for AKI, and that bicarbonate (OR 0.89; 95% CI 0.84-0.94) and partial pressure arterial oxygen/inspired oxygen fraction index (OR 0.99; 95% CI 0.98-0.99) could be protective factors. Conclusions: A high frequency of AKI was documented in COVID-19 patients, with several predictors: age, male sex, DM, CKD, CRP, ICU admission, and vasopressor support. AKI occurred more frequently in patients with higher disease severity and was associated with higher mortality and worse outcomes.

RESUMO Introdução: Lesão renal aguda (LRA) ocorre frequentemente em pacientes com COVID-19 e associa-se a maior morbidade e mortalidade. Conhecer riscos da LRA permite a identificação, prevenção e tratamento oportuno. Este estudo teve como objetivo identificar fatores de risco associados à LRA em pacientes hospitalizados. Métodos: Realizou-se estudo descritivo, retrospectivo, transversal e de componente analítico de pacientes adultos hospitalizados com COVID-19 de 1º de março a 31 de dezembro, 2020. Definiu-se a LRA pelos critérios de creatinina das diretrizes KDIGO-LRA. Informações sobre fatores de risco foram obtidas de prontuários eletrônicos. Resultados: Dos 934 pacientes, 42,93% desenvolveram LRA, 60,59% KDIGO-1 e 9,9% necessitaram de terapia renal substitutiva. Pacientes com LRA apresentaram maior tempo de internação, maior mortalidade e necessitaram de mais internações em UTIs, ventilação mecânica e suporte vasopressor. A análise multivariada mostrou que idade (OR 1,03; IC 95% 1,02-1,04), sexo masculino (OR 2,13; IC 95% 1,49-3,04), diabetes mellitus (DM) (OR 1,55; IC 95% 1,04-2,32), doença renal crônica (DRC) (OR 2,07; IC 95% 1,06-4,04), proteína C reativa (PCR) (OR 1,02; IC 95% 1,00-1,03), admissão em UTI (OR 1,81; IC 95% 1,04-3,16) e suporte vasopressor (OR 7,46; IC 95% 3,34-16,64) foram fatores de risco para LRA, e que bicarbonato (OR 0,89; IC 95% 0,84-0,94) e índice de pressão parcial de oxigênio arterial/fração inspirada de oxigênio (OR 0,99; IC 95% 0,98-0,99) poderiam ser fatores de proteção. Conclusões: Documentou-se alta frequência de LRA em pacientes com COVID-19, com diversos preditores: idade, sexo masculino, DM, DRC, PCR, admissão em UTI e suporte vasopressor. LRA ocorreu mais frequentemente em pacientes com maior gravidade da doença e associou-se a maior mortalidade e piores desfechos.

Percepción de la imagen corporal en relación con el índice de masa corporal en escolares de Chiapas / Perception of body image in relation to the body mass index in students of Chiapas

Fundamentos: La imagen corporal se define como la forma en que cada quien se percibe, y esto modifica lospensamientos, las emociones y el propio comportamiento. La adolescencia es un periodo de identificación y enla búsqueda de ello, las creencias erróneas sobre lo que el cuerpo debe de ser, puede conducirles a poner enriesgo su salud. Por tal motivo el objetivo de la presente investigación fue determinar la insatisfacción corporalen relación con el índice de masa corporal.Métodos: Estudio descriptivo, transversal con una población de 349 alumnos de los cuales se tomó una muestrade 81 alumnos a los cuales se les aplicó un cuestionario estructurado en tres apartados: a) datossociodemográficos, b) imagen corporal: test de Gardner y) datos antropométricos.Resultados: De acuerdo a la escala de IMC de la Organización Mundial de la Salud, se obtuvo que el 19,57% seencuentran en bajo peso, el 70,37% en peso normal, en el caso de sobrepeso y obesidad el 9,87%. En relacióncon la imagen e insatisfacción corporal, se encontró que el 87,65% presentaban insatisfacción corporal, tantohombres (46,92%), como mujeres (40,74%) indicaron no estar a gusto con su cuerpo.Conclusiones: El IMC, es independiente a la insatisfacción de la imagen corporal, aportando que, no se requierede un sobrepeso u obesidad para sentir se con un cuerpo inadecuado. (AU)

Background: Body image is defined as the way in which each person perceives themselves, and this modifiesthoughts, emotions and own behavior. Adolescence is a period of identification and in the search for it,erroneous beliefs about what the body should be can lead them to put their health at risk. For this reason, theobjective of this research was to determine body dissatisfaction in relation to body mass index.Methods: Descriptive, cross-sectional study with a population of 349 students from which a sample of 81students was taken and to which a questionnaire structured in three sections was applied: a) Sociodemographicdata, b) Body image: Gardner test and c) Anthropometric data.Results: According to the WHO BMI scale, 19.57% were underweight, 70.37% were of normal weight, and 9.87%were overweight and obese. In relation to body image and dissatisfaction, it was found that 87.65% weredissatisfied with their bodies. Presented body dissatisfaction, both men (46.92%) and women (40.74%)indicated that they were not comfortable with their body.Conclusions: BMI is independent of body image dissatisfaction, providing that it is not necessary to be overweight or obese to feel inadequate. (AU)

Efectos de la pandemia de COVID-19 en la compra y consumo de alimentos en universitarios / Effects of the COVID-19 pandemic on food purchase and consumption in college students

Fundamentos: El mundo vive una pandemia en los últimos 100 años la cual causo cambios bruscos demovilidad y en los hábitos de vida. El objetivo fue identificar los efectos de la pandemia de COVID-19 en lacompra y consumo de alimentos en estudiantes universitarios.Métodos: Estudio de tipo prospectivo, transversal y descriptivo en 335 estudiantes universitarios. Elinstrumento de evaluación compuesto por datos generales, escasez de alimentos y aumento de precio,cambios de hábitos y alimentación saludable, contó con 11 preguntas en total. Se hizo un análisis conestadística descriptiva y la Chi cuadrado de Pearson con nivel de significancia estadística de p<0,05.Resultados: La modalidad de compra más utilizada antes y durante el confinamiento fue la presencial(53,73%), mostrando una relación significativa entre el consumo de alimentos de bajo valor biológico(chatarra o comida basura) bajo factores de ansiedad, depresión y/o aburrimiento, y una relación entre laalimentación de los estudiantes y el interés por una alimentación saludable con valores de Chi- Cuadrado dePearson de 26,09 y 72,81 respectivamente.Conclusiones: No hubo cambios en la modalidad de adquirir los alimentos, se observaron modificaciones enel consumo de alimentos chatarra y el interés por mantener una alimentación más saludable durante elconfinamiento por la COVID-19. (AU)

Background: The world has experienced a pandemic in the last 100 years which has caused abrupt changesin mobility and lifestyle habits. Objective: To identify the effects of the COVID-19 pandemic on the purchaseand consumption of food in university students.Methods: Prospective, cross-sectional, descriptive study of 335 university students. The evaluationinstrument consisted of general data, food shortages and price increase, changes in habits and healthy eating,with 11 questions in total. An analysis was made with descriptive statistics and Pearson's Chi-square withstatistical significance level of p<0.05.Results: The most used modality of purchase before and during the confinement was face-to-face (53.73%),showed a significant relationship between the consumption of food of low biological value (junk) underfactors of anxiety, depression, boredom and a relationship between students' eating and interest in healthyeating with Pearson's Chi-square values of 26.09 and 72.81 respectively.Conclusions: There were no changes in the modality of acquiring their food, modifications are observed inthe consumption of junk food and interest in maintaining a healthier diet during the confinement by COVID19. (AU)

Afecciones, manifestaciones y repercusiones neurológicas del COVID-19 / COVID-19 conditions, manifestations, and neurological repercussions

Resumen Inetroducción: El Síndrome Respiratorio Agudo Severo (SARS-CoV-2) es la entidad patológica responsable de la actual pandemia que no solo genera un cuadro respiratorio distintivo sino que también se ha asociado con múltiples mecanismos de invasión al sistema nervioso central (SNC). Objetivo: Determinar las afecciones, manifestaciones y repercusiones neurológicas que puede generar la infección por SARS-CoV-2. Métodos: Revisión de la literatura científica de pacientes con infección por SARS-CoV-2, en quienes se evaluó desarrollo de afecciones, manifestaciones y repercusiones neurológicas, desenlace seleccionado en los estudios, presencia de afecciones micro y macroscópicas del SNC y periférico (SNP). Resultados: Se estudiaron 40 artículos que analizaban la familia y estructura del SARS-CoV-2, mecanismos fisiopatológicos, manifestaciones clínicas neurológicas y las posibles repercusiones a nivel sistema nervioso central. Conclusiones: El SARS-CoV-2 es una entidad patológica que se asocia a distintos mecanismos de intervención neurológica, por medio de infección directa al SNC, secundario a un proceso parainfeccioso y postinfeccioso, relacionado con el síndrome de tormenta de citoquinas, daño endotelial, trastornos trombóticos, adicionalmente de secundario a hipoxia, hipoxemia y fallo multiorgánico.

Abstract Introduction: Severe Acute Respiratory Syndrome (SARS-CoV-2) is the pathological entity responsible for the current pandemic that not only generates a distinctive respiratory pattern but has also been associated with multiple mechanisms of invasion of the central nervous system (CNS). Objective: To determine the affections, manifestations and neurological repercussions that SARS-CoV-2 infection can generate. Methods: Review of the scientific literature of patients with SARS-CoV-2 infection, in whom the development of conditions, manifestations and neurological repercussions, selected outcome in the studies, presence of micro and macroscopic conditions of the CNS and peripheral (PNS) were evaluated. Results: 40 articles were included where the family and structure of SARS-CoV-2, pathophysiological mechanisms, neurological clinical manifestations, and possible repercussions at the central nervous system level were analyzed. Conclusions: SARS-CoV-2 is a pathological entity that is associated with different mechanisms of neurological intervention, through direct infection to the CNS, secondary to a parainfectious and postinfectious process, related to cytokine storm syndrome, endothelial damage, thrombotic disorders, in addition to secondary to hypoxia, hypoxemia and multiple organ failure.

Síndrome hepatorrenal: revisión de la literatura

Contexto: el síndrome hepatorrenal es una disfunción renal que ocurre en pacientes con enfermedad hepática crónica como cirrosis hepática o enfermedad hepática aguda, caracterizada por la activación de mecanismos reguladores que conducen a la disminución de la tasa de filtrado glomerular. Clínicamente, el síndrome hepatorrenal se divide en dos tipos: el tipo 1 se caracteriza por una pérdida rápida y progresiva de la función renal, mientras que el tipo 2 se caracteriza por ser de progresión lenta y de mejor pronóstico. Objetivo: analizar la historia natural de la enfermedad que presentan los pacientes que desarrollan síndrome hepatorrenal. Metodología: se realizó una revisión de la literatura científica de manuscritos publicados sobre síndrome hepatorrenal, para evaluar la historia natural de esta patología. Resultados: no existen hallazgos clínicos específicos, sin embargo, sus manifestaciones clínicas reflejan la enfermedad hepática avanzada subyacente, la insuficiencia renal y las anomalías circulatorias presentes. Conclusiones: la opción terapéutica más adecuada es el trasplante hepático, pero no todos los pacientes pueden recibirlo, mientras se accede a dicho manejo una opción es el tratamiento medicamentoso con vasoconstrictores y albúmina.

Background: Hepatorenal syndrome is a renal dysfunction that occurs in patients with chronic liver disease such as liver cirrhosis or acute liver disease, characterized by the activation of regulatory mechanisms that lead to a decrease in the glomerular filtration rate. Clinically, hepatorenal syndrome is divided into two types, type 1 and type 2. Type 1 is characterized by a rapid and progressive loss of kidney function while type 2 is characterized by slow progression and a better prognosis. Purpose: To analyze the natural history of the disease presented by patients who develop hepatorenal syndrome. Methodology: A review of the scientific literature of published manuscripts on hepatorenal syndrome was carried out to evaluate the natural history of this pathology. Results: There are no specific clinical findings, however, its clinical manifestations reflect the underlying advanced liver disease, kidney failure, and circulatory abnormalities present. Conclusions: The most appropriate therapeutic option is liver transplantation, but not all patients can receive it, while accessing said management an option is drug treatment with vasoconstrictors and albumin.

Total mercury exposure risk and selenium content measuring on fishery products consumed by women of childbearing age from Bogota, Colombia / Riesgo de exposición a mercurio total y medición del contenido de selenio en productos de la pesca consumidos por mujeres en edad fértil de Bogotá, Colombia

Background: Dietary exposure to mercury in women of childbearing age could result in neurological effects on the fetus. A health risk assessment of total mercury by fishery products intake has not been conducted in this population group in Bogota, Colombia. On the other hand, it has been suggested that selenium content on fishery products may have a protective effect against mercury toxicity. Nevertheless, selenium content on fish species marketed in Bogota has not been determined. Objective: Exposure risk to total mercury and selenium content on fishery products consumed by women of childbearing age from Bogota, Colombia, were assessed. Methods: Total mercury and selenium concentrations for products available at fish stores and supermarkets were determined. The exposure risk to total mercury was estimated considering the intake of these products by women of childbearing age group. Results: Total mercury highest concentrations were 0.8166 mg/kg in mota (Calophysusmacropterus), and 0.6275 mg/kg in catfish (Pseudoplatystoma tigrinum). On the other hand, the highest selenium concentration was 0.6471 mg/kg in nicuro (Pimelodus blochii). Finally, it was established that for women of childbearing age group, health risk of exposure to total mercury due to mota intake exceeded by 8.56-fold the reference dose. Conclusions:Mota intake considerably increases exposure risk to total mercury on women of childbearing age from Bogota, Colombia. The selenium levels established in the fishery products assessed, except for catfish and mota, are theoretically suggestive of a protective effect of selenium against mercury toxicity. Consequently, continuous total mercury concentrations monitoring is required to protect health of women of childbearing age and the general population from Bogota, Colombia

Antecedentes: La exposición dietética al mercurio en mujeres en edad fértil podría provocar efectos neurológicos en el feto. En Bogotá, Colombia no se han realizado evaluaciones de riesgo por la exposición al mercurio total debido a la ingesta de productos de la pesca en este grupo de la población. Por otro lado, ha sido sugerido que el contenido de selenio en los productos de la pesca podría tener un efecto protector frente a la toxicidad por mercurio, sin embargo, el contenido de selenio en las especies de peces comercializadas en Bogotá, Colombia no ha sido determinado. Objetivo: Evaluar el riesgo de exposición al mercurio total y el contenido de selenio en los productos de la pesca consumidos por las mujeres en edad fértil de Bogotá, Colombia. Métodos: Se determinaron las concentraciones de mercurio total y selenio en distintos productos de la pesca disponibles en pescaderías y supermercados. El riesgo de exposición a mercurio total se estimó considerando la ingesta de estos productos por parte de un grupo de mujeres en edad fértil. Resultados: Las concentraciones más altas de mercurio total fueron de 0.8166 mg/kg en mota (Calophysus macropterus) y 0.6275 mg/kg en bagre (Pseudoplatystoma tigrinum). Por otro lado, la concentración más alta de selenio fue de 0.6471 mg/kg en nicuro (Pimelodus blochii). Finalmente, se estableció que el riesgo de exposición a mercurio total, debido a la ingesta de mota, excedió en 8.56 veces la dosis de referencia en el grupo de mujeres en edad fértil. Conclusiones: La ingesta de mota aumenta el riesgo de exposición al mercurio total en las mujeres en edad fértil de Bogotá, Colombia. Por otro lado, los niveles de selenio identificados en los productos evaluados, excepto en bagre y mota, teóricamente sugieren un posible efecto protector del selenio contra la toxicidad por mercurio. Considerando lo indicado, es necesario realizar un monitoreo continuo de las concentraciones de mercurio total en los productos de la pesca, con el fin de proteger la salud de las mujeres en edad fértil y de la población general de Bogotá, Colombia

Conocimientos, prácticas y prevalencia de uso de medidas de protección adecuada frente a la radiación ultravioleta en habitantes de Bogotá D.C. (2013-2018) / Knowledges, practices, and prevalence of the use of appropriate protective measures facing ultraviolet radiation (UVR) in inhabitants of Bogotá D.C. (2013-2018) / Conhecimento, práticas e prevalência do uso de medidas de proteção adequadas contra a radiação ultravioleta em habitantes de Bogotá D.C. (2013-2018)

Objetivo: describir los conocimientos, las prácticas y la prevalencia de uso de medidas de protección adecuadas frente a la radiación ultravioleta (RUV) en una muestra de habitantes de Bogotá D.C., Colombia (2013-2018). Método: estudio de corte transversal a partir de encuestas realizadas por la Secretaría Distrital de Salud (SDS) en diferentes sectores de Bogotá. Se entrevistaron transeúntes de áreas públicas de concentración masiva en las 20 localidades de Bogotá, los cuales fueron incluidos de forma secuencial y por conveniencia. Se estudiaron aspectos sociodemográficos, fenotípicos, antecedente de interés, conocimientos y prácticas relacionadas con la exposición a la RUV. Resultados: se analizaron 8.420 encuestas, donde el 66 % (n: 5.560) eran sujetos de género femenino, con una mediana de edad de 38 años. La mayoría de los encuestados se ubicaron en los estratos socioeconómicos del I al III (95,6 %; n: 8.051). El 27 % declaró una ocupación laboral al aire libre (n: 2.268) y el 50 % reportaron exponerse a la RUV los siete días de la semana (n: 4.255). El 70 % de los participantes (n: 5.870) reconoció que la RUV es un factor de riesgo de cáncer de piel, pero tan sólo el 20,8 % (n: 1.753) reportó prácticas adecuadas de protección. Conclusiones: a pesar del alto nivel de conocimiento frente a los riesgos de la RUV existe un bajo porcentaje de uso de medidas de protección en esta muestra de habitantes de Bogotá. Se deben reforzar las estrategias que conduzcan a incrementar la protección frente a la RUV en este grupo poblacional.

Objective: To describe knowledge, practices, and prevalence of the use of appropriate protective measures facing ultraviolet radiation (UVR) in a sample of inhabitants of Bogotá D.C., Colombia (2013-2018). Method: A cross-sectional study from surveys carried out by the District Secretariat of Health (SDS according to its Spanish initials) in different sectors of Bogotá. Transients of public areas of mass concentration in 20 localities of Bogotá were interviewed. These were included in a sequential way and by convenience. Sociodemographic, phenotype aspects were studied, along with interests, knowledge, and practices related to UVR exposure. Results: 8,420 surveys were analyzed, where 66% (n: 5,560) were female, with an average age of 38 years. Most people surveyed were in socioeconomic levels I to III (95.6%; n: 8,051). 27% declared that they worked outside (n: 2,268), and 50% reported exposure to UVR seven days a week (n: 4,255). 70% of participants (n: 5,870) recognized that UVR is a skin cancer risk factor, but only 20.8% (n: 1,753) reported appropriate protection measures. Conclusions: Despite high levels of knowledge regarding the risk of UVR, there is a low level of use of protection measures in this sample of inhabitants in Bogotá. Strategies must be reinforced that lead to an increase of protection against UVR in this population group.

Objetivo: descrever os conhecimentos, as práticas e a prevalência do uso de medidas de proteção adequadas contra a radiação ultravioleta (RUV) em uma amostra de habitantes de Bogotá D.C., Colômbia (2013-2018). Método: estudo transversal baseado em inquéritos realizados pela Secretaria Distrital de Saúde (SDS) em diferentes setores de Bogotá. Foram entrevistados transeuntes de áreas públicas de maior concentração nas 20 localidades de Bogotá; eles foram incluídos sequencialmente e por conveniência. Foram estudados aspectos sociodemográficos e fenotípicos, histórico de interesse, conhecimentos e práticas relacionadas à exposição à RUV. Resultados: foram analisados 8.420 inquéritos, dos quais 66% (n: 5.560) eram do sexo feminino, com mediana de idade de 38 anos. A maioria dos entrevistados estava localizados nos estratos socioeconômicos de I a III (95,6%; n: 8.051). 27% declararam ocupação ao ar livre (n: 2.268) e 50% relataram exposição à RUV sete dias por semana (n: 4.255). 70% dos participantes (n: 5.870) reconheceram que a RUV é um fator de risco para câncer de pele, mas apenas 20,8% (n: 1.753) relataram práticas de proteção adequadas. Conclusões: apesar do alto nível de conhecimento sobre os riscos da RUV, há um baixo percentual de uso de medidas de proteção nesta amostra de habitantes de Bogotá. Estratégias que levem ao aumento da proteção contra RUV nesse grupo populacional devem ser reforçadas.

Mutation in mce operons attenuates Mycobacterium tuberculosis virulence.

On the Mycobacterium tuberculosis genome there are four mce operons, all of which are similar in sequence and organization, and code for putatively exported proteins. To investigate whether Mce proteins are essential for virulence, we generated knock-out mutants in mce1, mce2 and mce3 operons of M. tuberculosis and evaluated their ability to multiply in a mammalian host. The allelic replacement was confirmed in each mutant strain by Southern blotting. RT-PCR experiments demonstrated the lack of in vitro expression of mutated genes in Deltamce1 and Deltamce2 mutants. On the other hand, no expression of mce3 was detected in either the wild-type or mutant strains. Similar doubling time and growth characteristics in in vitro culture were observed for mutants and parental strains. The intratracheal route was used to infect BALB/c mice with the Deltamce3, Deltamce2 and Deltamce1 mutants. Ten weeks after infection, all mice infected with the Deltamce mutants survived, while those infected with the wild-type strain died. This long survival correlated with very low counts of colony-forming units (CFU) in the lungs. Deltamce1-infected mice developed very few and small granulomas, while animals infected with Deltamce3 or Deltamce2 mutants showed delayed granuloma formation. Mice infected with Deltamce1 did not develop pneumonia, while animals infected with Deltamce3 and Deltamce2 mutants showed small pneumonic patches. In spleens, bacterial counts of mutant strains were less reduced than in lungs, compared with those of wild-type. In contrast, no such attenuation was observed when the intraperitoneal route was used for infection. Moreover, Deltamce1 mutants appear to be more virulent in lungs after intraperitoneal inoculation. In conclusion, mce operons seem to affect the virulence of M. tuberculosis in mice, depending on the route of infection. Hypotheses are discussed to explain this last issue. Thus, mutants in these genes seem to be good candidates for vaccine testing.

Tecnoestrés en población mexicana y su relación con variables sociodemográficas y laborales / Technostress in the Mexican population and its relationship with sociodemographic and labor variables

Resumen Objetivo: Medir la relación entre variables sociodemográficas, variables laborales y la frecuencia del uso de las tecnologías, con el nivel de tecnoansiedad, tecnofatiga y tecnoadicción como experiencias del tecnoestrés, en una muestra de adolescentes, jóvenes y adultos mexicanos. Método: Se aplicaron las escalas para medir tecnoestrés y tecnoadicción de Cazares & Villavicencio (2019) y un cuestionario de variables sociodemográficas y laborales de elaboración propia, a un total de 981 participantes mexicanos entre 13 y 69 años, utilizando la herramienta de formularios de Google. Los datos obtenidos fueron sometidos a un análisis de nivel descriptivo, correlacional e inferencial (Kerlinger & Lee, 2002), con ayuda del programa estadístico SPSS v.20. Resultados: Respecto a la tecnofatiga, los resultados arrojaron diferencias significativas por sexo (U = 104026.50, p=.037) y antigüedad en el trabajo [χ2(3) = 11.213, p = .011] y una significancia marginal por estado civil (U = 78329.00, p=.058). En cuanto a la tecnoadicción, se encontraron diferencias significativas por estado civil (U = 76121.50, p=.012) y ocupación [χ2(2) = 4.698, p =.008]. Con relación a la tecnoansiedad, fueron arrojadas diferencias significativas por tipo de empresa (U = 61348.00, p=.049). Finalmente, se encontró que las personas con mayor nivel de escolaridad, los directivos y los empresarios independientes, presentaron mayor tecnoansiedad, tecnofatiga y tecnoadicción. Conclusiones: Los resultados permiten afirmar que en México existe la presencia de tecnoestrés. Además, se demuestra la relación entre las experiencias del tecnoestrés y variables sociodemográficas (sexo, estado civil, ocupación y escolaridad) y laborales (antigüedad laboral, tipo de empresa y nivel de puesto). Los resultados constituyen las primeras aportaciones de la investigación del tecnoestrés en México, país que impulsa el uso de la tecnología.

Abstract Objective: To measure the relationship between sociodemographic variables, labor variables, and technology frequency of use with the level of technostress experiences such as techno-anxiety, techno-fatigue, and techno-addiction, using a sample of Mexican adolescents, youth, and adults. Method: The participants of the study were 981 Mexican nationals aged 13-69. The scales implemented to measure technostress and techno-addiction were the ones used in Cazares & Villavicencio (2019) and a sociodemographic and labor variables questionnaire created by the authors, implemented using Google's form tool. Data obtained were subjected to a descriptive, correlational, and inferential level analysis (Kerlinger & Lee, 2002), using the statistical software SPSS v.20. Results: Regarding techno-fatigue, the results showed significant differences on the basis of sex (U = 104026.50, p = 0.037) and seniority [χ2(3) = 11.213, p = 0.011] and a marginal significance on the basis of marital status (U = 78329.00, p = .058). Regarding techno-addiction, significant differences were found on the basis of marital status (U = 76121.50, p = 0.012) and occupation [χ2(2) = 4.698, p = 0.008]. Regarding techno-anxiety, significant differences were found on the basis of company type (U = 61348.00, p = 0.049). Finally, it was found that people who received better schooling, such as directors and independent entrepreneurs, showed greater techno-anxiety, techno-fatigue, and techno-addiction. Conclusions: The results confirm that technostress is prevalent in Mexico. In addition, there is a confirmed relationship between technostress experiences, sociodemographic variables (sex, marital status, occupation, and schooling), and labor variables (seniority, company type, and position level). The results constitute the first technostress research contributions in Mexico, a country that encourages the use of technology.

Traumatismo craneoencefálico en niños. Hospital General de Medellín y Clínica Somer de Rionegro, 2010-2017 / Pediatric Traumatic Brain Injury. Hospital General of Medellin and Clínica Somer of Rionegro, 2010- 2017

RESUMEN Objetivo: describir las características sociodemográficas, aspectos clínicos y complicaciones de los niños de 0 a 10 años de edad que sufrieron traumatismo craneoencefálico, atendidos en el Hospital General de Medellín y en la Clínica Somer de Rionegro entre los años 2010 y 2017. Métodos: estudio descriptivo retrospectivo, toma como fuente de información las historias clínicas de los niños con diagnósticos relacionados con el traumatismo craneoencefálico entre 2010-2017. Se calcularon las proporciones de las variables sociodemográficas, circunstanciales, espacio-temporales y clínicas. Resultados: se encontraron 224 pacientes con traumatismo craneoencefálico, el 64,7 % de los casos fueron de sexo masculino, la edad promedio fue de 4,5 años. El trauma ocurrió con mayor frecuencia en el domicilio del paciente entre los días de la semana en las horas de la tarde. La causa principal del trauma fue caída (75 %), seguido por accidentes de tránsito (13,3 %). La gravedad del traumatismo se midió con la escala de coma de Glasgow, el 78 % fue leve, hubo un caso fatal y 7 (3 %) tuvieron complicaciones motoras durante la hospitalización. Conclusión: los hallazgos de este estudio coinciden con las principales características del traumatismo craneoencefálico de la población pediátrica en el mundo, amplía la información regional y local para el desarrollo de estrategias de prevención, diagnóstico y seguimiento a largo plazo de los pacientes.

SUMMARY Objective: To describe the demography, clinical presentation and complications associated with traumatic brain injury (TBI) in a cohort of children, ages 0-10, treated at Hospital General de Medellín and Clínica Somer between 2010-2017. Methods: Cross sectional retrospective study chart review of all children with a diagnosis of TBI between 2010 and 2017. There were systematic review and recording of demographic information, mechanism of injury, clinical presentation, and associated complications. Results: A total of 224 patients with TBI were identified. Among them, 64.7% were males and mean age was 4.5 years. Injuries most frequently occurred at the patient's home, during the afternoon hours and between Monday and Friday. The most common mechanisms of injury were falls (75%), followed by motor vehicle accidents (13.3%). Severity of injury, measured by Glasgow coma scale, found that 78% of cases were mild. Seven (3%) of cases had neuromuscular complications during hospitalization and one TBI related death was identified. Conclusion: Findings of this study are consistent with the known characteristics of pediatric TBI worldwide. This information may be used to improve prevention, diagnosis, and long term follow-up.