Pierre Robin Sequence: An Updated Evidence-Based Treatment Proposal.

BACKGROUND: The Pierre Robin sequence (PRS) is characterized by the presence of micrognathia, glossoptosis, and respiratory obstruction during the neonatal period, its prompt recognition allows to mitigate the associated morbidity and mortality. A diagnosis and treatment algorithm was previously proposed based on data from the literature to guide therapeutic efforts; therefore, it was proposed to carry out a new search for relevant evidence to update or complement it. METHODS: A literature review of the subject was conducted in PubMed, Embase, and Cochrane databases, corresponding to the period between November 2016 and September 2021. Using the GRADE methodology, 38 articles from different clinical studies that discussed diagnostic tests or therapeutic approaches, directly or indirectly compared, were selected and evaluated. RESULTS: After evaluating and analyzing the selected articles, the new information was incorporated into an updated algorithm according to the most recent evidence found for the diagnosis and comprehensive management of patients with PRS. CONCLUSION: To date, there is no consensus in the literature on the treatment of patients with PRS nor are there multicenter studies comparing different management modalities. The indications to proceed with surgical strategies do not present changes with respect to the previous article. Nutritional monitoring is the main objective, and the study of oral feeding is essential in all scenarios.

Importance of γ-secretase in the regulation of liver X receptor and cellular lipid metabolism.

Presenilins (PS) are the catalytic components of γ-secretase complexes that mediate intramembrane proteolysis. Mutations in the PS genes are a major cause of familial early-onset Alzheimer disease and affect the cleavage of the amyloid precursor protein, thereby altering the production of the amyloid ß-peptide. However, multiple additional protein substrates have been identified, suggesting pleiotropic functions of γ-secretase. Here, we demonstrate that inhibition of γ-secretase causes dysregulation of cellular lipid homeostasis, including up-regulation of liver X receptors, and complex changes in the cellular lipid composition. Genetic and pharmacological inhibition of γsecretase leads to strong accumulation of cytoplasmic lipid droplets, associated with increased levels of acylglycerols, but lowered cholesteryl esters. Furthermore, accumulation of lipid droplets was augmented by increasing levels of amyloid precursor protein C-terminal fragments, indicating a critical involvement of this γ-secretase substrate. Together, these data provide a mechanism that functionally connects γ-secretase activity to cellular lipid metabolism. These effects were also observed in human astrocytic cells, indicating an important function of γ-secretase in cells critical for lipid homeostasis in the brain.

Ritmo hematofágico de Simulium quadrivittum loew, 1862 (Diptera: Simuliidae) / Hematophagic rate of Simulium quadrivittum loew, 1862 (Diptera: Simuliidae)

Se detectó una relación de la actividad hematofágica de Siumuliium quedrivittatum con la variación de la posición solar el norte de la loma "La Cañada" (21- 43- N y 82- 54'0), la zona central de Isla de la Juventud; se obtuvieron 2 parábolas que responden a las ecuaciones y=11.61 + 0,137 S+ (4,727) S* y y=17,6 + 0,415 S + (-9,495)S*, para los valores de la mañana y la tarde respectivamente. Se encontró una mayor actividad hematofágica promedio durante la tarde (U=25, p<0,05)