Balance and Gait of Frail, Pre-Frail, and Robust Older Hispanics.

Older Hispanics are an understudied minority group in the US, and further understanding of the association between frailty, gait and balance impairments in disadvantaged older Hispanics is needed. The objectives of this study were to compare the balance and gait of older Hispanics by their frailty status. Sixty-three older Hispanics (21 men, 42 women, mean age 75 ± 7 years) attending senior centers in disadvantaged neighborhoods were grouped by their frailty status and completed balance and walking tests at a preferred speed and during street crossing simulations. Sixteen percent (n = 10) of the participants were frail, 71% (n = 45) were pre-frail, and 13% (n = 8) were robust. Frail participants had poorer balance than robust participants (F = 3.5, p = 0.042). The preferred walking speed of frail and pre-frail participants was lower (F = 6.3, p < 0.011) and they took shorter steps (F > 3.5, p = 0.002) than robust participants. During street crossing conditions, frail participants had wider steps (F = 3.3, p = 0.040), while pre-frail participants walked slower (F = 3.6, p = 0.032), and both took shorter steps than robust participants (F > 3.5, p < 0.043). Frailty and pre-frailty were prevalent and associated with gait and balance impairments in disadvantaged older Hispanics. The findings can inform the development of programs and interventions targeting this vulnerable underserved population.

Changes on Walking During Street Crossing Situations and on Dorsiflexion Strength of Older Caribbean Americans After an Exercise Program: A Pilot Study.

The objective of this pilot study was to evaluate a 6-month exercise program completed by 10 older Caribbean Americans. Assessments were done at baseline and 3 and 6 months, and included walks on an instrumented mat at preferred speed, and during street crossing simulations with regular (10 s) and reduced time (5 s). There were no significant differences on preferred walking speed over time. Differences between the street crossing conditions were found only at 6 months. Significant changes over time among the assessments were found only during street crossing with reduced time. Street crossing with reduced time was the only walking condition sensitive to capture changes associated with participating in the exercise program. There was a significant increase in dorsiflexion strength overtime. At 6 months it was significantly higher than at baseline and 3 months. The program was feasible, acceptable, and had some positive effects on walking, knee flexion, and dorsiflexion strength.

Vagotomia modifica o efluxo do cálcio nas ilhotas pancreáticas / Vagotomy changes calcium eflux in pancreatic islets

A participação do sistema nervoso parassimpático na modulação da secreção de insulina manifesta-se claramente durante a fase cefálica que se segue ao estímulo iniciado pelo estímulo sensorial provocado pela presença do alimento na cavidade oral. O objetivo deste trabalho foi avaliar se a vagotomia subdiafragmática seletiva do ramo pancreático poderia modificar a permeabilidade ao Ca2+ da membrana plasmática das células beta. Para avaliar os efeitos da vagotomia usamos o principal secretagogo que é a glicose e o potencializador carbamilcolina. Os estudos de e fluxo de 45Ca2+ foram realizados em ilhotas de ratos controle ou desnervados isoladas por digestão com colagenase e perfundidas com KREBS contendo os secretagogos. As ilhotas isoladas de ratos 15 e 30 dias após a vagotomia do ramo pancreático não responderam ao estímulo com 16,7 mM de glicose e também apresentaram alteração na sensibilidade à carbamilcolina (CCh 100 μm) adicionada à solução contendo 5,6 mM de glicose. Nossos resultados sugerem que o nervo vago (ramo pancreático) participa da regulação do processo secretório da insulina pelas células beta pancreáticas. Este efeito pode estar associado à modulação da respostas induzidas pela glicose e reguladas pelo neurotransmissor acetilcolina, considerado modulador da secreção de insulina.

The participation of the parasympathetic nervous system in insulin secretion modulation is clearly evident during the cephalic phase that follows the sensorial stimulus provoked by food in the mouth. The objective of this study was to evaluate if selective subdiaphragmatic vagotomy of the pancreatic branch could alter 45Ca2+ permeability in the plasmatic membrane of pancreatic β cell. To assess the effects of vagotomy, we used glucose and the potentializer carbamylcholine on the glucose effects. Analysis of 45Ca2+ efflux was accomplished in isolated islets by digestion with collagenase and perfused with KREBS and carbamylcholine in rats from groups control and denervaded. After 15 and 30 days of the pancreatic branch vagotomy, the isolated islets did not respond to a glucose stimulus of 16,7 mM and also presented alteration in carbamylcholine sensibility (CCh 100 μm) when added to the solution containing 5,6mM of glucose. Our results suggest that the vagus nerve (pancreatic branch) contributes with regulationof insulin secretory process of pancreatic β cells. This effect could be associated to the modulation of responses induced by glucose and the regulation of acetylcholine, a neurotransmitter modulator of insulin secretion.