Retinoic acid induces antimicrobial peptides and cytokines leading to Mycobacterium tuberculosis elimination in airway epithelial cells.

Tuberculosis (TB) is the leading cause of death by a single infectious agent, Mycobacterium tuberculosis (Mtb). Alveolar macrophages and respiratory epithelial cells are the first cells exposed to Mtb during the primary infection, once these cells are activated, secrete cytokines and antimicrobial peptides that are associated with the Mtb contention and elimination. Vitamins are micronutrients that function as boosters on the innate immune system, however, is unclear whether they have any protective activity during Mtb infection. Thus, we investigated the role of vitamin A (retinoic acid), vitamin C (ascorbic acid), vitamin D (calcitriol), and vitamin E (alfa-tocopherol) as inductors of molecules related to mycobacterial infection in macrophages and epithelial cells. Our results showed that retinoic acid promotes the expression of pro- and anti-inflammatory molecules such as Thymic stromal lymphopoietin (TSLP), ß-defensin-2, IL-1ß, CCL20, ß-defensin-3, Cathelicidin LL-37, TGF-ß, and RNase 7, whereas calcitriol, ascorbic acid, and α-tocopherol lead to an anti-inflammatory response. Treatment of Mtb-infected epithelial cells and macrophage-like cells with the vitamins showed a differential response, where calcitriol reduced Mtb in macrophages, while retinoic acid reduced infection in epithelial cells. Thereby, we propose that a combination of calcitriol and retinoic acid supplementation can drive the immune response, and promotes the Mtb elimination by increasing the expression of antimicrobial peptides and cytokines, while simultaneously modulating inflammation.

Habilidades de estudio en aspirantes a ingresar en la carrera de medicina / Study skills in medical school applicants

INTRODUCCIÓN: El desempeño académico se debe, en gran medida, a la organización personal del alumno (cómo estudiar, dónde estudiar, cuándo estudiar, etc.), lo que posibilita una buena calidad de aprendizaje. OBJETIVO: Presentar los resultados obtenidos en la evaluación de las habilidades de estudio en los aspirantes a ingresar en la carrera de medicina de la Facultad de Medicina de la Universidad del Salvador. SUJETOS Y MÉTODOS: Estudio cuantitativo, transversal y descriptivo, que comprendió a 263 aspirantes de los cursos de ingreso en 2019 y 2020 a los que se les administró una encuesta que incluye tres escalas (dificultades de atención y concentración; estrategias de comprensión, análisis e integración de textos; y estrategias de resolución de problemas) y seis preguntas sobre la organización del tiempo, y acerca del lugar y el contexto de estudio. RESULTADOS: Se observó en los aspirantes una mayor habilidad en las estrategias para la resolución de problemas respecto de las estrategias para la comprensión, el análisis y la integración de textos. El 12,2% tiene dificultades de atención y concentración. Al 14,8% le gusta escuchar música o radio mientras estudia y un 3,8% siempre o casi siempre estudia con la televisión encendida

INTRODUCTION: Academic performance is largely due to the student's personal organization (how to study, where to study, when to study, etc.), which enables a good quality of learning. AIM: To show the results obtained in the evaluation of study skills of medical school applicants at Universidad del Salvador. SUBJECTS AND METHODS: It is a quantitative, descriptive and cross-sectional study that included 263 applicants from 2019 and 2020 admission courses, who were administered a survey with three scales (attention and concentration difficulties; comprehension, analysis and integration of texts strategies; and problem-solving strategies), plus six questions about time organization and the place and study context. RESULTS: A higher ability in problem-solving strategies than in comprehension, analysis and integration of texts strategies was observed. 12.2% of applicants have attention and concentration difficulties. 14.8% like listening to music or the radio while studying, and 3.8% always or usually study with the television on. CONCLUSIONS: These evaluations are useful for the teaching of 'Learning methodology' subject in the admission course, as well as the other subjects. In addition, they allow students to critically analyze the study abilities they have developed throughout their previous training stages

Quality assurance for antimicrobial susceptibility testing of Neisseria gonorrhoeae in Latin American and Caribbean countries, 2013-2015.

OBJECTIVES: A Neisseria gonorrhoeae antimicrobial susceptibility quality control comparison programme was re-established in Latin America and the Caribbean to ensure antimicrobial susceptibility data produced from the region are comparable nationally and internationally. METHODS: Three panels, consisting of N. gonorrhoeae isolates comprising reference strains and other characterised isolates were sent to 11 participating laboratories between 2013 and 2015. Antimicrobial susceptibilities for these isolates were determined using agar dilution, Etest or disc diffusion methods. Modal minimum inhibitory concentrations (MICs) for each panel isolate/antibiotic combination were calculated. The guidelines of the Clinical and Laboratory Standards Institute were used for interpretations of antimicrobial susceptibility. The agreement of MICs with the modal MICs was determined for each of the participating laboratories as well as for each of the antibiotics tested. RESULTS: Five of 11 laboratories that participated in at least one panel had an overall average agreement between participants' MIC results and modal MICs of >90%. For other laboratories, agreements ranged from 60.0% to 82.4%. The proportion of agreement between interpretations for all the antibiotics, except penicillin and tetracycline, was >90%. The percentages of agreement between MIC results and their modes for erythromycin, spectinomycin, cefixime and azithromycin were >90%. Tetracycline, ceftriaxone and ciprofloxacin agreement ranged from 84.5% to 89.1%, while penicillin had 78.8% agreement between MICs and modal MICs. CONCLUSIONS: The participating laboratories had acceptable results, similar to other international quality assurance programmes. It is important to ensure continuation of the International Gonococcal Antimicrobial Susceptibility Quality Control Comparison Programme to ensure that participants can identify and correct any problems in antimicrobial susceptibility testing for N. gonorrhoeae as they arise and continue to generate reproducible and reliable data.