Prevalence of Alzheimer's disease in rural and urban areas in Cuba and factors influencing on its occurrence: epidemiological cross-sectional protocol.

INTRODUCTION: According to the World Alzheimer's Report 2019, around 50 million people suffer from dementia, worldwide. Observational analysis revealed the existence of particular factors associated with the onset and progression of Alzheimer's disease (AD). There are no international homogeneous principles for the early detection and evaluation of memory impairment and possible AD. This work aimed at (1) determining the prevalence of possible AD in the elderly residing in urban and rural regions in Cuba and (2) identifying the main factors that could significantly influence on its occurrence. METHODS AND ANALYSIS: The study includes four neuropsychological tests (Clock Drawing Test, Mini-Mental Status Examination, Short Portable Mental Status Questionnaire, Cognitive and Non-Cognitive Alzheimer's Disease Assessment Scale) and two scales (Clinical Dementia Rating and Global Deterioration Scale). Moreover, the protocol includes a survey with demographic and socioeconomic information, educational level, occupation, health, neuropsychological status of subjects, familial pathological history, comorbidities and lifestyles. The study will comprise a total of 1092 subjects aged ≥60, of both genders, and from every ethnic group settled in rural and urban areas. PRIMARY OUTCOMES: prevalence of possible AD. SECONDARY OUTCOMES: correlation among risk and protective factors and AD, and comparison of the performance of neuropsychological tests and scales. ETHICS AND DISSEMINATION: This research met the ethical codes of the Declaration of Helsinki. The Scientific Research Council of the Promoting Research Institute and the Ethics Committee of the Health Authorities approved the protocol. The proper written informed consent is also incorporated. The results of the survey will be published in scientific papers and shared with the Health Authorities of each municipality.

Efecto de la combinación de bases nutritivas con el inhibidor sobre la recuperación de salmonelas / Effect of combining nutrient bases and inhibitor on recovery of Salmonella

INTRODUCCIÓN: las salmonelas son las causantes más frecuentes de enfermedades transmitidas por alimentos a nivel mundial. El caldo selenito cistina es un medio de enriquecimiento selectivo utilizado para la recuperación de especies de salmonelas en muestras de alimentos, aguas, heces y otros materiales de importancia sanitaria. OBJETIVO: evaluar la combinación de bases nutritivas obtenidas por métodos originales con el selenito de sodio para garantizar la adecuada recuperación de especies de salmonelas en el caldo selenito cistina. MÉTODOS: se realizó un estudio comparativo con diferentes bases nutritivas, que evaluó la promoción de crecimiento bacteriano de seis cepas de Salmonella y Shigella. Se prepararon dos variantes y se inocularon los microorganismos seleccionados a una concentración aproximada de 3 × 108 unidades formadoras de colonia por mililitro. El incremento de la biomasa se determinó a través de la medición de la absorbancia en un espectrofotómetro a 640 nanómetros cada una hora. Se comparó el comportamiento del medio caldo selenito cistina formulado por ingredientes con el caldo selenito cistina de Merck frente a los microorganismos de interés. Se determinó productividad y selectividad del medio de cultivo. RESULTADOS: la variante que contiene la mezcla de bases nutritivas (peptona bacteriológica Z, peptona de soya e hidrolizado enzimático de caseína) facilitó una mejor recuperación de las cepas ensayadas, mostró diferencias significativas (p< 0,05) con respecto a la variante que contiene solo hidrolizado enzimático de caseína. El medio experimental que contenía la mezcla de bases nutritivas con el selenito de sodio, mostró una recuperación de Salmonella a bajas concentraciones, similar al de referencia e inhibió mejor Escherichia coli a bajas concentraciones. A altas concentraciones ninguno de los dos medios pudo inhibir el crecimiento de E. coli. La productividad para ambos medios, resultó satisfactoria en el intervalo de 0,1 a 1, al igual que la selectividad con un valor aproximado de 3. CONCLUSIONES: la combinación de bases nutritivas originales con el selenito de sodio permitió una adecuada recuperación de las especies de salmonelas.

INTRODUCTION: Salmonella are the most common causes of food-borne disease worldwide. Selenite cystine broth is a selective enrichment medium used for the recovery of Salmonella species in samples of food, water, feces and other materials of clinical importance. OBJECTIVE: Evaluate the combination of nutrition bases obtained by original methods and sodium selenite to ensure appropriate recovery of Salmonella species in selenite cystine broth. METHODS: A comparative study was conducted with various nutrition bases to evaluate the fostering of bacterial growth in six strains of Salmonella and Shigella. Two variants were prepared and the microorganisms selected were inoculated at an approximate concentration of 3 × 108 colony-forming units per milliliter. Absorbance was measured with a 640 nanometer spectrophotometer every hour to determine biomass increase. Behavior of the selenite cystine broth medium formulated by ingredients was compared with that of Merck cystine selenite broth in the presence of the microorganisms of interest. Determination was performed of the productivity and selectivity of the culture medium. RESULTS: The variant containing the mixture of nutrient bases (bacteriological peptone Z, soybean peptone and casein enzymatic hydrolysate) facilitated better recovery of the strains tested, with significant differences (p< 0.05) with respect to the variant containing casein enzymatic hydrolysate alone. The experimental medium containing the mixture of nutrient bases and sodium selenite displayed Salmonella recovery at low concentrations in a manner similar to the reference medium and inhibited Escherichia coli more efficiently at low concentrations. At high concentrations neither medium was able to inhibit the growth of E. coli. Productivity was satisfactory in both media, ranging between 0.1 and 1, and so was selectivity, which reached an approximate value of 3. CONCLUSIONS: The combination of original nutrition bases and sodium selenite allowed appropriate recovery of Salmonella species.