RESUMEN
The safety and efficacy of gossypol continues to be controversial. The aim of this study was to evaluate gossypol as a contraceptive pill for men at doses lower than those previously prescribed and in men from various ethnic origin. A total of 151 men from Brazil, Nigeria, Kenya, and China were divided into two groups. Both groups received 15 mg gossypol/day for 12 or 16 weeks to reach spermatogenesis suppression. Subjects were then randomized to either 7.5 or 10 mg/day for 40 weeks. In addition, 51 men were enrolled as a control group. In all, 81 subjects attained spermatogenesis suppression. Only one man discontinued treatment because of tiredness. Potassium levels fluctuated within the normal range. FSH increased consistently. Testicular volume decreased, but after discontinuation, values returned to levels not statistically different from admission. Of 19 subjects on the 7.5 mg/day dose group, 12 recovered sperm counts >20 million/mL within 12 months of discontinuing gossypol. In the 10 mg/day group, sperm counts recovered in only 10 of 24 subjects. Eight of the 43 patients remained azoospermic 1 year after stopping gossypol. All men diagnosed with varicocele failed to reverse spermatogenesis suppression. Gossypol blood levels indicated that sperm suppression occurs independently of concentration, whereas spermatogenesis recovery appears to be concentration-dependent. Gossypol may become a medical alternative to surgical vasectomy when the delay in onset of infertility is acceptable. When taken for 1 year, gossypol causes no reduction in sexual desire or frequency of intercourse. The possibility of reversal, occurring in 51% of the men on this regimen within 1 year after stopping gossypol, is an advantage of this compound as compared with surgical sterilization in many parts of the world.
PIP: The safety and efficacy of gossypol continues to be controversial. The aim of this study was to evaluate gossypol as a contraceptive pill for men at doses lower than those previously prescribed and in men from various ethnic origin. A total of 151 men from Brazil, Nigeria, Kenya, and China were divided into two groups. Both groups received 15 mg gossypol/day for 12 or 16 weeks to reach spermatogenesis suppression. Subjects were then randomized to either 7.5 or 10 mg/day for 40 weeks. In addition, 51 men were enrolled as a control group. In all, 81 subjects attained spermatogenesis suppression. Only 1 man discontinued treatment because of tiredness. Potassium levels fluctuated within the normal range. FSH increased consistently. Testicular volume decreased, but after discontinuation, values returned to levels not statistically different from admission. Of 19 subjects in the 7.5 mg/day dose group, 12 recovered sperm counts higher than 20 million/ml within 12 months of discontinuing gossypol. In the 10 mg/day group, sperm counts recovered in only 10 of 24 subjects. 8 of the 43 patients remained azoospermic 1 year after stopping gossypol. All men diagnosed with varicocele failed to reverse spermatogenesis suppression. Gossypol blood levels indicated that sperm suppression occurs independently of concentration, whereas spermatogenesis recovery appears to be concentration-dependent. Gossypol may become a medical alternative to surgical vasectomy when the delay in onset of infertility is acceptable. When taken for 1 year, gossypol causes no reduction in sexual desire or frequency of intercourse. The possibility of reversal, occurring in 51% of the men on this regimen within 1 year after stopping gossypol, is an advantage of this compound as compared with surgical sterilization in many parts of the world.
Asunto(s)
Anticonceptivos Masculinos/sangre , Gosipol/sangre , Espermatogénesis/efectos de los fármacos , Adulto , Brasil , China , Anticonceptivos Masculinos/administración & dosificación , Anticonceptivos Masculinos/efectos adversos , Hormona Folículo Estimulante/sangre , Gosipol/administración & dosificación , Gosipol/efectos adversos , Humanos , Kenia , Cinética , Masculino , Nigeria , Potasio/sangre , Testículo/anatomía & histologíaRESUMEN
Hypokalemia has been associated with the taking of gossypol, a potential oral antifertility drug for men. Because the frequency of this response differed in different parts of the world, this study was done to learn if "normal" serum [K+] also differed. [K+] was measured by flame photometry in serum from apparently normal men from Austria (n = 30), China (53), Brazil (100), the Dominican Republic (38), and the US (103), and in plasma from Nigerian men (82). The mean (SD) for [K+] in Chinese men, 3.82 (0.27) mmol/L, was lower than that in Brazilians [4.06 (0.29) mmol/L], Austrians [4.14 (0.44) mmol/L], Dominicans [4.37 (0.33) mmol/L], or Americans [4.38 (0.37) mmol/L]. Apparently there are regional differences in average serum [K+], with men in China having lower serum [K+] than men elsewhere. This may predispose them to hypokalemia.
Asunto(s)
Potasio/sangre , Adolescente , Adulto , Austria , Brasil , China , República Dominicana , Humanos , Masculino , Persona de Mediana Edad , Nigeria , Valores de Referencia , Estados UnidosRESUMEN
The effects of theophylline at a dose of 2 mg/kg/day (with resultant serum concentrations of 2.8 to 3.9 micrograms/ml) were observed in seven premature infants with severe idiopathic apnea. The frequency of apneic episodes decreased 62 +/- 9% (SEM) and the frequency of episodes of bradycardia decreased 73 +/- 9% following 24-48 hours of this therapy. No changes in ventilatory response to CO2 resting respiratory minute volume, arterial blood gas values, resting heart rate, or serum electrolyte concentrations were observed. Theophylline at this dose appears to be a safe and effective treatment for idiopathic apnea in premature infants. It works by a mechanism other than increasing CO2 sensitivity.