Short term effect of hubble-bubble smoking on voice.

OBJECTIVE: To investigate the short term effect of hubble-bubble smoking on voice. STUDY DESIGN: Prospective study. MATERIAL: Eighteen non-dysphonic subjects (seven men and 11 women) with a history of hubble-bubble smoking and no history of cigarette smoking underwent acoustic analysis and laryngeal video-stroboscopic examination before and 30 minutes after hubble-bubble smoking. RESULTS: On laryngeal video-stroboscopy, none of the subjects had vocal fold erythema either before or after smoking. Five patients had mild vocal fold oedema both before and after smoking. After smoking, there was a slight increase in the number of subjects with thick mucus between the vocal folds (six, vs four before smoking) and with vocal fold vessel dilation (two, vs one before smoking). Acoustic analysis indicated a drop in habitual pitch, fundamental frequency and voice turbulence index after smoking, and an increase in noise-to-harmonics ratio. CONCLUSION: Even 30 minutes of hubble-bubble smoking can cause a drop in vocal pitch and an increase in laryngeal secretions and vocal fold vasodilation.

Expression of biologically active human insulin-like growth factor-I following intramuscular injection of a formulated plasmid in rats.

Recent evidence has shown that insulin-like growth factor-I (IGF-I) plays an important role in the development, maintenance, and regeneration of peripheral nerves and skeletal muscle. IGF-I offers the potential to treat neuromuscular diseases in humans. We have developed a nonviral gene therapy method to express and produce localized and sustained therapeutic levels of IGF-I within target muscles by intramuscular injection of formulated plasmids. The purpose of the present study was to demonstrate that intramuscular injection of a plasmid encoding human IGF-I (hIGF-I) and engineered to restrict expression to skeletal muscle produces sustained local concentrations of biologically active hIGF-I. Normal rats received a single intramuscular injection of plasmids formulated as a complex with polyvinylpyrrolidone (PVP). Results show that hIGF-I mRNA and hIGF-I protein were detectable in the injected muscles for the duration of the study (28 days), whereas the hIGF-I protein was not detected in blood. Biological activity of hIGF-I was determined by immunodetection of a nerve-specific growth-associated protein, GAP-43, an indicator of motor neuron sprouting. Placement of human growth hormone (hGH) 3' untranslated region enhanced GAP-43 staining, probably due to improved secretion of hIGF-I. Enhanced immunoreactivity of GAP-43 was observed in muscles injected with the formulated hIGF-I plasmid when compared to controls. These results demonstrate that intramuscular injection of hIGF-I plasmid formulated as a complex with PVP produces a localized and sustained level of biologically active hIGF-I.