Low dose gossypol for male contraception

Aim: To ascertain whether the side effects of gossypol, hypokalemia and irreversibility, could be avoided on dose re-duction. Methods: Seventy-seven male volunteers were divided into 3 groups: control (22 cases), 10 mg gossypol(29 cases) and 12.5 mg (26 cases). Serum levels of testosterone, FSH and LH were measured by RIA and potassiumby flame photometry. Spema counts and motility were examined before and regularly after treatment for the evaluationof contraceptive efficacy. Results: The average sperm density and motility started to decrease significantly by theend of month 2 of medication and gradually reached the infertility levels ( < 4 million /mL) in both treated groups. Af-ter that the 10 mg group was asked to take the same dose every other day for up to a total observation period of 16-18months for the maintenance of infertility. Subjects in the 12.5 mg group did not take gossypol any more so as to ob-serve the length of the loading dose required, but in a few, a maintenance dose of 12.5 mg every other day was insti-tuted for a few more months. In both treated groups, none of the spouses was pregnant during the maintenance dose pe-riod. Serum levels of potassium, FSH, LH and testosterone were not significantly changed and not a single volunteercomplained of myoasthenia. After cessation of drug administratioin, the semen data returned to pretreatment levels.Conclusion: A regimen with 10 or 12.5 mg of gossypol as the daily loading dose and 35 or 43.75 mg as the week-ly maintenance dose could induce infertility in male volunteers without developing hypokalemia or irreversibility.(Asian J Androl 2000 Dec; 2: 283-287)

Determination of stacking fault energies in a high-Nb TiAl alloy at 298 K and 1273 K

The stacking fault energies of Ti-46Al-8.5Nb-0.2W alloy at 298 K and 1273 Kwere determined. The principle for the determination of the stacking fault energies is based on thefact that the stacking fault energy and the elastic interaction energy acting on the dissociatedpartial dislocations are equal. After the compress deformations with the strain of 0.2% at 298 K and1273 K, and water quench to maintain the dislocation structures deformed at 1273 K, thedissociation distances between two partial dislocations were determined by weak beam transmissionelectron microscopy (WBTEM) technique. Based on these dissociation distances and the correspondingcalculation method, the stacking fault energies were determined to be 77-81 mJ/m^2 at 298 K and tobe 57-60mJ/m^2 at 1273 K respectively.

Effect of Chinese Herbs Bu-shen on Expression of Pituitary PRL-R and PrRP-R in the Bromocriptine-induced Hypoprolactin Rat Abortion Model

Objective To study the effect of Chinese herbs preparation Bu-shen on pituitary prolactin-releasing peptide receptor (PrRP-R) and prolactin receptor (PRL-R) expression in the bromocriptine-induced rat abortion model Materials & Methods Female SD rats were divided into five groups randomly. Group A,B,C and D were injected with bromocriptine [0. 3 mg/(kg · d)] during the pregnant day 6～ 8, respectively. Group B was given powder of Bu-shen herbs [3 g/(kg · d)]. Group C was injected with prolactin (8 IU) twice a day and Group D with progesterone [(8 mg/kg · d) in the pregnant day 1～ 11. The rats in Group E were normal pregnant rats. All these rats were killed at the pregnant day 12 to observe the expression of PrRP-R, PRL-R from the pituitary using RT-PCR. Results The pregnant rate and total number of litters in Group A were significantly lower than those in Group B, C, D and E (P＜0. 01) and the expression of PrRP-R and PRL-R in the pituitary of Group A was higher than that of any other group. Conclusion Preparation Bu-shen plays a regulatory role in the secretion of prolactin possibly via modulating rats' hypothalamus and pituitary.