RESUMO
In Venezuela, the isolation of hantaviruses from rodents and the detection, in 1999, of a clinically confirmed human case of hantavirus infection led to increased interest in these viruses. In an attempt to estimate the problem posed by such viruses in Venezuela, ELISA based on purified, recombinant, nucleoprotein were used to check 1380 human serum samples for the presence of IgG antibodies to hantavirus. The ELISA results, as confirmed by indirect immunofluorescence and Western-blot assays, indicated that 23 (1.7%) of the serum samples contained antibodies to hantaviruses. Seroprevalences were similar among all age-groups and for both genders and were no higher among rural populations with a relatively high risk of exposure to rodents than among the overall study population. Although the numbers of samples involved were small, the seroprevalence among the subjects who were residents of Carabobo state was much higher than the overall value (10.3% v. 1.7%; P < 0.01). Human infection with hantavirus appears uncommon but widely distributed in Venezuela.
Assuntos
Anticorpos Antivirais/análise , Infecções por Hantavirus/imunologia , Imunoglobulina G/análise , Orthohantavírus/imunologia , Adolescente , Adulto , Western Blotting/métodos , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Imunofluorescência/métodos , Orthohantavírus/isolamento & purificação , Infecções por Hantavirus/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Venezuela/epidemiologiaRESUMO
Salbutamol, a beta 2-adrenergic agonist, is being extensively used in Venezuela as a brochodilator in the treatment of asthma in children. Previous reports have shown oral salbutamol either to inhibit or not to affect growth hormone (GH) secretion. We evaluated the effect of oral salbutamol (0.1 mg/kg every 6 hours for 3 months) on GH secretion in eight prepubertal short children with mild asthma. Levels of GH during sleep (samples taken every 30 minutes from 9 PM to 6 AM) and after GH-releasing hormone ([GHRH] 1 microgram/kg intravenously [IV]) were measured before, at 24 hours, and at 3 months of salbutamol treatment. Overnight integrated concentrations of GH and peak GH levels following GHRH diminished significantly after 24 hours of salbutamol therapy (from 4.5 +/- 1.3 to 3.4 +/- 0.8 micrograms/L and from 46.6 +/- 47.3 to 16.2 +/- 7.9 micrograms/L, respectively, P < .05). However, GH levels after 3 months of salbutamol were not different from basal levels (4.5 +/- 1.3 v 5.1 +/- 5.1 +/- 2.9 micrograms/L during the overnight studies and 46.6 +/- 47.3 v 37.8 +/- 30.4 micrograms/L after GHRH). Our data suggest an inhibition of both spontaneous and stimulated GH secretion following short-term oral salbutamol ingestion, but this suppressive effect is not maintained with its long-term use.