[Determination of the missrreporting of energy intake by Goldberg and Black in the FACSA cohort. Pilot study.] / Determinación de la infradeclaración de la ingesta de energía por el método de Goldberg y Black en la cohorte FACSA. Estudio piloto.

Introduction: Introduction: the Goldberg and Black method estimates dietary underreporting in epidemiological food consumption studies. This method compares the self-reported energy intake of the subjects with the estimate of their total energy expenditure. Objective: to evaluate underreporting and overreporting at individual and group levels in Health Sciences students. Material and methods: the study was cross-sectional and prospective; the participants recorded their food consumption through two dietary records, one on the weekend and the other on the weekdays. They previously answered to sign an informed consent letter, after which the physical activity questionnaire (IPAQ) they were also weighed and measured, and then the basal metabolic rate (BMR) was estimated, It calculated later the declared intake (EI)/BMR ratio, and finally, the cut-off points to determine under-declarers, over declarators and plausible declarators. Results: we found 14.81 % underreporting at the individual level and 44.44 % at the group level. The subjects with a higher BMI and those who performed strenuous physical activity were the ones who underreported the most. The subjects underreported performed moderate and severe physical activity at the group level. Conclusions: it is crucial to carry out this methodology to verify the results of dietary evaluation since underreporting affects the estimation of nutrient intake and can alter the associations between diet and diseases in epidemiological studies.

Introducción: Introducción: el método de Goldberg y Black se utiliza para estimar la infradeclaración dietética en los estudios epidemiológicos de consumo de alimentos. Este método se basa en la comparación de la ingesta de energía autodeclarada por los sujetos con la estimación de su gasto energético total. Objetivo: evaluar la infradeclaración y sobredeclaración a nivel individual y grupal en estudiantes de Ciencias de la salud. Material y métodos: el estudio fue transversal y prospectivo; los participantes registraron el consumo de alimentos por medio de dos registros dietéticos, uno de fin de semana y otro de entre semana. Previamente se les solicitó la firma de una carta de consentimiento informado y después se les aplicó el cuestionario de actividad física (IPAQ). También se les peso y midió, luego se estimó la tasa metabólica basal (BMR), posteriormente se calculó la relación de la ingesta declarada (EI)/BMR y, por último, se eligieron los puntos de corte para determinar quiénes eran infradeclaradores, sobredeclaradores y declaradores plausibles. Resultados: se encontró un 14,81 % de infradeclaración a nivel individual y un 44,44 % a nivel grupal. Los sujetos con mayor IMC y los que realizaban actividad física intensa son los que mayor infradeclaración reportan y, a nivel grupal, los sujetos que realizan actividad física moderada e intensa también fueron infradeclaradores. Conclusiones: es crucial llevar a cabo esta metodología para verificar los resultados de la evaluación dietética ya que la infradeclaración afecta a la estimación de la ingesta de nutrientes y puede alterar las asociaciones entre dieta y enfermedades en los estudios epidemiológicos.

Relationship Among Blastocystis, the Firmicutes/Bacteroidetes Ratio and Chronic Stress in Mexican University Students.

The role played by Blastocystis in humans has been a subject of discussion due to its intestinal effects and modifications in the intestinal microbiota. We aimed to analyze the relationship between Blastocystis subtypes ST1-4 and 7, the Firmicutes to Bacteroidetes ratio (F/B ratio) of fecal microbiota, and chronic stress in university students. This study had a cross-sectional design with a sample of 202 students. We analyzed fecal and hair samples, and stress inventories were applied to the students. The results showed a frequency of Blastocystis-colonized students of 52.97%. Regarding fecal microbiota, a median RAU of 0.801 for Firmicutes and 0.82 of Bacteroidetes were obtained, with an F/B ratio of 0.83. A low F/B ratio (66.04%) was more frequent in Blastocystis-colonized students, whereas a high F/B ratio (68.09%) (p = < 0.0001) was found in the Blastocystis-non-colonized. Only Blastocystis ST3 did not significantly correlate with a low F/B ratio (p = 0.290). The ST4 was associated with lower values of cortisol (p = 0.030), psychological stress (p = 0.040), and lower frequency of constipation (p = 0.010). Only two students with the ST1 had abdominal pain (p = 0.007). Our results suggest that colonization by Blastocystis subtypes can modify the intestinal microbiota due to a decreased ratio between the two most representative phyla (F/B). Also, the results of this study show that ST4 colonization is related to a lower level of chronic stress.

Characterization of human astrovirus cell entry.

Human astroviruses (HAstV) are a frequent cause of gastroenteritis in young children and immunocompromised patients. To understand the early steps of HAstV infection in the highly permissive Caco-2 cell line, the binding and entry processes of the virus were characterized. The half-time of virus binding to the cell surface was about 10 min, while virus decapsidation took around 130 min. Drugs affecting clathrin-mediated endocytosis, endosome acidification, and actin filament polymerization, as well as those that reduce the presence of cholesterol in the cell membrane, decreased the infectivity of the virus. The infection was also reduced by silencing the expression of the clathrin heavy chain (CHC) by RNA interference or by overexpression of dominant-negative mutants of dynamin 2 and Eps15. Furthermore, the entry of HAstV apparently depends on the maturation of endosomes, since the infection was reduced by silencing the expression of Rab7, a small GTPase involved in the early- to late-endosome maturation. Altogether, our results suggest that HAstV enters Caco-2 cells using a clathrin-dependent pathway and reaches late endosomes to enter cells. Here, we have characterized the mechanism used by human astroviruses, important agents of gastroenteritis in children, to gain entry into their host cells. Using a combination of biochemical and genetic tools, we found that these viruses enter Caco-2 cells using a clathrin-dependent endocytic pathway, where they most likely need to travel to late endosomes to reach the cytoplasm and begin their replication cycle.