Gustavo García de la Mora

A POSSIBLE ROLE OF PROGESTERONE RECEPTOR IN MOUSE OOCYTE IN VITRO FERTILIZATION REGULATED BY NORETHISTERONE AND ITS REDUCED METABOLITE

BACKGROUND The contraceptive effect of the progestogen norethisterone (NET) and its main metabolites 5alpha-NET and 3beta,5alpha-NET has been demonstrated in several species, and most studies have focused on the effects of these compounds in the uterus. We previously reported that 5alpha-NET inhibits the progesterone (P(4))-induced acrosome reaction in pig and mouse spermatozoa and induces severe morphological damage in two-cell fertilized mouse oocytes. STUDY DESIGN The main goal of this study was to analyze the possible role of P(4) receptor (PR) in the effects of NET and 5alpha-NET on the oocyte fertilization process. Different steroid treatments were used with or without cumulus-enclosed oocytes. RESULTS It was demonstrated that NET increases the percentage of fertilized oocytes in the same manner as P(4) does, while 5alpha-NET reduces the percentage of fertilized oocytes. This effect was not reversed by P(4) in the same concentrations. CONCLUSION A possible molecular mechanism for the effects of 5alpha-NET may be through a PR localized in the oocyte plasma membrane.

A diterpenic acid from Stevia lucida

Abstract A new furan diterpenic acid was isolated from Stevia lucida . On the basis of IR, 1 H NMR and mass spectra, as well as chemical evidence, the acid was assigned the structure 5β,9β H ,10α,-labda-7,13(16),14-trien-15,16-epoxy-19-oic-acid.

Long-acting contraceptive agents: Norethisterone esters of monoalkenyl and monoalkynyl acids

The synthesis of nine new esters of norethisterone (17 alpha-ethynyl-17 beta-hydroxyestr-4-en-3-one) is described, with the esterifying acids bearing an acetylenic or olefinic function in a chain of eight or nine carbon atoms, for evaluation as long-acting contraceptive agents.

Orcinol derivative compound with antioxidant properties protects Langerhans islets against streptozotocin damage

To design and synthesize an orcinol derivative compound, 3‐formyl‐2,4‐dihydroxy‐5,6‐dimethyl sodium benzoate (A4), as an antioxidant molecule and to test its effects on oxidative stress in an in‐vitro model of apoptosis of pancreatic rat beta cells induced by streptozotocin (STZ).

In situ free radical and carbocation reactions between alkylbenzenes promoted by a bentonite clay

The reaction between n-alkylbenzenes and bromine catalyzed with a bentonitic clay in absence of light, afforded directly substituted phenyl methanes or α-halogenated alkylbenzenes. This one-pot general method, can be used for the preparation of benzylhalides, alkyl substituted or unsubstituted methylene bridge phenyl methanes.