Firefighters' basal cardiac autonomic function and its associations with cardiorespiratory fitness.

BACKGROUND: Firefighters' activities require constant adjustments of the cardiovascular system with cardiac autonomic function (CAF) playing an important role. Despite the crucial role of CAF in regulating stress response, little is known about firefighters' CAF. OBJECTIVE: We aimed to characterize the resting on-duty and off-duty CAF of male firefighters, in association with cardiorespiratory fitness (CRF). METHODS: We evaluated 38 firefighters in an on-duty rest condition and 26 firefighters in an off-duty laboratory-controlled condition. CAF was addressed by means of heart rate variability (HRV). We compared HRV measurements between CRF categories (<12METs vs ≥12METs). Wilcoxon, Mann-Whitney texts and Spearman correlation were used and General Linear Model was applied for age and BMI adjustments. RESULTS: Firefighters' resting CAF is characterized by a predominant sympathetic modulation and a large inter-individual dispersion in all HRV indices, in both groups. We found a positive correlation between a higher CRF, the overall CAF and the higher parasympathetic activity (p <  0,03). Firefighters with CRF ≥12 METs showed a higher parasympathetic modulation. CONCLUSIONS: Firefighters' resting CAF is characterized by a predominant sympathetic modulation and a large inter-individual dispersion in all HRV indices, in both groups. Our results support mandatory physical training focused in improving firefighters' CAF as a cardiopretective effect.

Prevalence and costs of hospitalizations for poisoning and accidental intoxication in Brazilian elderly

A cross-sectional study of secondary data/information obtained from the Hospital Information System (HIS) spanning the years 2008 - 2009 was performed. The distribution of the main hospital admissions by gender, age, color/race, region and federal unit of residence, average expenditure and average length of hospital stay, year of hospitalization and mortality rates (MR) were studied. The data collected were tabulated by TabNet and keyed into Microsoft Excel 2007. It was verified that elderly males (54.3%), from 60 to 69 years old (50.6%), nonwhites (36.3%) and residents of Southeast and North regions of the country had the highest rates of hospitalization. Seniors were hospitalized for an average of 4.8 days, and the major causes were exposure to alcohol (43.7%) and to drugs (33.9%). Expenses related to hospital admissions were, on average, R$ 529,817.70. The highest mortality rates were recorded among females (MR = 4.34), in elderly, 80 years or older (MR = 10.16) and Caucasians (MR = 3.95), where pharmacological substances with action on the Autonomic Nervous System were the leading cause of death. There are demographic differences in morbi-mortality of these elderly since, although men and younger elderly were the main victims, women and elderly of advanced age have greater mortality. The leading causes of hospitalization were alcohol and drugs.

Realizou-se um estudo transversal de dados secundários obtidos no Sistema de Informação Hospitalar (SIH), nos anos 2008/2009. Estudou-se a distribuição das principais internações segundo sexo; faixa etária; cor/raça; região e unidade federativa de residência; valor médio pago e média de permanência das internações hospitalares; ano de internação e as taxas de mortalidade (TM). Os dados coletados foram tabulados por meio do TabNet e transcritos para o Programa Microsoft Excel® 2007. Verificou-se que idosos do sexo masculino (54,3%), com 60 e 69 anos de idade (50,6%), não brancos (36,3%) e residentes nas regiões Sudeste e Norte do País apresentaram os maiores percentuais de internação hospitalar. Idosos ficam em média 4,8 dias internados, sendo as principais causas a exposição ao álcool (43,7%) e a medicamentos (33,9%). Os gastos com as internações equivaleram a R$ 529.817,70. As maiores taxas de mortalidade foram registradas no sexo feminino (TM=4,34), em idosos entre 80 anos e superior (TM=10,16) e pessoas brancas (TM=3,95), sendo as substâncias farmacológicas de ação sobre o Sistema Nervoso Autônomo maiores causas do óbito. Existem diferenças demográficas na morbimortalidade desses idosos, visto que apesar de homens e idosos mais jovens serem as principais vítimas, mulheres e idosos com idade mais avançada morrem mais. Sendo as principais causas de internação o álcool e os medicamentos.

The accumulation of guanethidine by human blood platelets.

1. When human blood platelets were incubated aerobically in plasma containing 2 x 10(-7) to 10(-3)M radioactive guanethidine for 10 min to 6 hr, the drug was accumulated against a concentration gradient until concentration ratios (platelet/plasma) of up to 80:1 were obtained.2. The decline in rate of uptake after 3 hr appeared to result from a decrease in platelet viability, because accumulation was reduced by prolonged incubation before addition of guanethidine.3. Uptake was energy-dependent because it was inhibited by cold and ouabain.4. Sodium ions were essential for guanethidine uptake and retention of 5-hydroxytryptamine (5-HT).5. Accumulation was inhibited by 5-HT, desipramine, cocaine, dexamphetamine, bretylium, tyramine and noradrenaline; bethanidine, p-chlorophenylalanine and (-)-alpha-methyldopa were inactive.6. Guanethidine was tightly bound to platelets, only 10% being lost from labelled cells during 60 min incubation in drug-free plasma; but efflux was increased by addition of amphetamine.7. The binding sites for guanethidine seemed to be different from those for 5-HT since guanethidine accumulation was independent of 5-HT levels, and neither guanethidine uptake or release were affected by reserpine.8. Guanethidine was not metabolized by platelets or plasma in vitro.9. We consider that, if our results regarding uptake, binding and release of guanethidine are confirmed in vivo, and also found to apply to other pharmacologically active agents, then the eventual loss of a platelet-bound substance may increase pharmacological action by raising plasma levels.