Anti-CTH monoclonal antibody, clone MAAG2863

Endogenous hydrogen sulfide (H2S) is a potent vasodilator and proangiogenic second messenger synthesized from L-cysteine by cystathionine beta-synthase (CBS) and cystathionine gamma-lyase (CTH). Estrogens are potent vasodilators that stimulate H2S biosynthesis in uterine arteries (UA) in vivo; however, the underlying mechanisms are unknown. We hypothesized that estrogens stimulate H2S biosynthesis in UA endothelial cells (UAEC) via specific estrogen receptor (ER)-dependent mechanisms. In cultured primary UAEC, treatment with estradiol-17 beta (E-2 beta) stimulated CBS and CTH mRNAs and proteins in a time- and concentration-dependent fashion. As little as 0.1 nM E-2 beta was effective in increasing CBS and CTH expressions and these stimulatory effects maximized with 10-100 nM E-2 beta at 48-72 h. E-2 beta also activated CBS and CTH promoters in UAEC, leading to CBS and CTH expression. Treatment with E-2 beta stimulated H2S production, which was blocked by specific inhibitors of either CBS or CTH and their combination and the ER antagonist ICI 182780. Treatment with either specific agonist of ER alpha or ER beta stimulated both CBS and CTH mRNA and protein expressions and H2S production to levels similar to that of E-2 beta. Specific antagonist of either ER alpha or ER beta blocked E-2 beta-stimulated CBS and CTH mRNA and protein expressions and H2S production. Combinations of either ER alpha or ER beta agonists or their antagonists had no additive effects. Thus, E-2 beta stimulates H2S production by upregulating CBS and CTH mRNA and protein expressions through specific ER alpha or ER beta-dependent CBS and CTH transcription in UAEC in vitro. Estradiol-17 beta stimulates uterine artery endothelial cell hydrogen sulfide biosynthesis.

Catalysts with Co nanoparticles (NPs) entrapped in N,S-codoped carbon shells were successfully fabricated by pyrolysis of porous organic polymers (POPs) with cobalt salts. The encapsulated structure consisting of Co NPs and N,S-codoped carbon layers was verified by TEM, XRD, and X-ray photoelectron spectroscopy. The catalysts displayed excellent activity and stability for the catalytic transfer hydrogenation (CTH) of nitrobenzene with formic acid under base-free conditions. Furthermore, the resultant catalysts allowed for highly efficient and selective transfer hydrogenation of various functionalized nitroarenes to the corresponding anilines. Through control experiments, the covered Co NPs were identified as active sites for CTH. The incorporation of S into the N-doped carbon lattice promoted the electron transfer from metallic cobalt NPs to their shells, which played a significant role in the acceleration of CTH. Moreover, the Co-NSPC-850 catalyst pyrolyzed at 850 degrees C showed excellent stability in the recycling experiments.