Effects of Mefepronic Acid (2-Phenoxy-2-Methyl Propionic Acid) on Hepatic Metabolism and Reproductive Parameters in Postpartum Dairy Cows.

This study investigates the effects of mefepronic acid (MA), a PPAR-α agonist, on hepatic metabolic functions and reproduction of postpartum dairy cows. Sixty Friesian cows were divided into Group A (administered 5g of MA IM, within 24 hrs after calving, on the 3rd and 5th day postpartum) and Group B (control). All the cows were blood sampled within 24 hrs of calving (Day 0), on Day 3, 5, 10, 15, 30, and 40 postpartum. On plasma, metabolic and biochemical parameters were determined. Liver biopsies were performed on Day 0, 15 and 30 for the evaluation of hepatic lipid and glycogen content. Reproductive parameters were also evaluated. In Group A, blood HDL, glucose and cholesterol increased till the end of the study, in accordance with the histological results. PPAR-α immunopositive cells increased in liver slices of Group A, too. Reproductive parameters improved in Group A. This study highlights the beneficial effects of mefepronic acid on the hepatic metabolism and reproductive parameters of post-partum dairy cows

Silicon photonics in Pirelli

Silicon is the dominant material in the microelectronic industry and silicon photonics is rapidly gaining importance as a technological platform for a wide range of applications in telecom, and optical interconnect. It allows the implementation of many photonic functions through the use of wafer-scale technologies normally used for advanced CMOS-processing. In this paper some of the most important issues toward a practical implementation of Silicon photonics into an industrial device will be addressed: low loss waveguides, polarization handling, tunability, hitless switching. A tunable Add-Drop multiplexer has been chosen as a case Study of a fully integrated device

In vitro effects of L-arginine on spontaneous and Homocysteine-induced contractility of pregnant canine uteri

The L-Arginine-Nitric Oxide Synthase-Nitric Oxide (L-Arg-NOS-NO) system exerts a pivotal role in the maintenance of uterine quiescence during pregnancy, whereas Homocysteine (Hcy) promotes uterine contractility. The aim of this study was to test the in vitro effects of L-Arg on spontaneous and Hcy-induced contractions of uteri excised from pregnant bitches. 104 strips cut from pregnant uteri were mounted in an organ bath. 40 out of 104 strips (16 from mid-gestation uteri and 24 from close to term uteri, respectively) were exposed to cumulative doses of L-Arg; 40 strips (16 from mid-gestation-uteri and 24 from close to term-uteri, respectively) were exposed to N-nitro-L-arginine methyl ester (L-NAME), a NOS antagonist; the remaining 24 strips (from close-to-term uteri) were first exposed to a single dose of Hcy and then to increasing doses of L-Arg. L-Arg showed no effects on spontaneous contractility both in mid-gestation- and close to term-uterine strips, whereas it promoted a relaxant effect on Hcy-induced contractility. On the contrary, L-NAME increased amplitude of contraction both in mid-gestation and close to term strips. These findings suggest that the L-Arg-NO system is present in the uterus of pregnant bitches and that Hcy is able to modulate its actions. Further investigation of this system may provide the basis of future obstetrical therapies in bitches

Bovine ovarian follicular cysts: in vitro effects of lecirelin, a GnRH analogue

This study investigates the mechanisms of action by which a GnRH analogue may modulate the contractility of the bovine ovarian follicular wall. The in vitro evaluation of the spontaneous basal contractility of bovine preovulatory and cystic follicles was performed, followed by testing the effects of lecirelin, a GnRH analogue, on their basal contractility. Strips of tissue in isolated organ bath were employed.In addition, to better investigate the mechanism of action of lecirelin, the study of the effects of cumulative doses of nifedipine (a calcium channel blocker), phentolamine (an α-adrenoceptor antagonist) and reserpine (an inhibitor of the vesicular up-take of catecholamines) alone and, at the highest doses employed, associated to lecirelin, was set up.The results demonstrate that in basal conditions and after the addition of lecirelin, the strips from preovulatory follicles contract significantly more than strips from cysts.Furthermore, among the patterns of contractility evoked by the three drugs employed, the one induced by nifedipine was the only one unaffected by the addition of lecirelin.The data obtained provide the hypothesis that one of the main mechanisms of action of GnRH, could involve calcium channels

In vitro activity of human chorionic gonadotropin (hCG) on myometrium contractility

LH/hCG receptor has been found in extragonadal tissues in human and animals. The myometrium presents such receptors but their functional role is still not clear. Aim of our study was to test the activity of human chorionic gonadotropin (hCG) on bovine uterine contractility. Uterine strips from cows both during follicular and luteal phases were mounted in an organ bath and then exposed to increased doses of hCG. The amplitude of the myometrium contractions were significantly decreased in the follicular and luteal phase but the frequency was not affected. These findings prove a relaxing effect of hCG in the bovine uterus, as already shown in the sow and human, and its possible functional role in modulating uterine contractility