ABSTRACT
The reaction Cl + isobutene (i-C4H8) was reported by Suits et al. to proceed via, in addition to abstraction, an addition-elimination path following a roaming excursion of Cl; a near-zero translational energy release and an isotropic angular distribution observed at a small collision energy characterized this mechanism. We employed a new experimental method to further characterize this roaming mechanism through observation of the internal distribution of HCl (v, J) and their temporal behavior upon irradiation of a mixture of Cl2C2O2 and i-C4H8 in He or Ar buffer gas. With 1-3 Torr buffer gas added to approach the condition of small collision energy, the intensities of emission of HCl (v = 1, 2) and the HCl production rates increased significantly; Ar shows a more significant effect than He because Ar quenches Cl more efficiently to reduce the collisional energy and facilitate the roaming path. According to kinetic modeling, the rate of addition-elimination (roaming) increased from kE ≈ 2 × 105 s-1 when little buffer gas was present to ~1.9 × 106 s-1 when 2-3 Torr of Ar was added, and the branching ratio for formation of [HCl (v = 2)]/[HCl (v = 1)] increased from 0.02 ± 0.01 for abstraction to 0.06 ± 0.01 for roaming.
ABSTRACT
Androgen-related diseases impair the well-being of many aging men. Unfortunately, the medications used to treat these diseases have many side effects. Therefore, there is a significant need for the development of novel drugs to treat androgen-related diseases. In this study, we investigated the effects of Monascus cursory extraction (M-CE) on androgen-related diseases, including androgenetic alopecia (AGA), benign prostatic hyperplasia (BPH) and prostate cancer. We found that M-CE suppressed baldness in male B6CBAF1/j mice. Furthermore, M-CE decreased PSA levels, indicating a protective effect of M-CE on testosterone-induced hyperplasia. M-CE also significantly decreased tumor volume and tumor incidence in an N-methyl-N-nitrosourea (MNU)/testosterone-induced rat prostate cancer model and markedly decreased dihydrotestosterone (DHT) but not testosterone. Additionally, PCNA expression was decreased in the prostate of rats treated with M-CE. These results suggest that M-CE could be a new potential therapeutic candidate for the treatment of androgen-related diseases.
