Effects of Oleamide on the Vasomotor Responses in the Rat.

Introduction: Cardiovascular effects of endocannabinoids (eCBs) have generated considerable interest since it has been suggested that the eCB system could become the new pharmacological target, either by blocking its activity or by promoting its effects on several cardiovascular diseases such as hypovolemic and septic shock or hypertension. The purpose of this study was to examine the effects of oleamide on several vasomotor responses in adult rats. Materials and Methods: Blood pressure (BP) was measured both directly and indirectly. Coronary flow was quantified with Langendorf preparation, and the vasomotor responses induced by oleamide were analyzed in the aortic rings. Results: Oleamide induced a decrease in BP, by both direct and indirect methods, which were dose dependent. An increase in coronary flow was observed with Langendorf preparation depending on the dose. Oleamide produced a vasodilator response in aortic rings pre-contracted with phenylephrine (10-5 M), which was concentration and endothelium dependent. This relaxing effect was of minor magnitude than that induced with the same dose on BP. L-NAME did not modify these effects. However, indomethacin induced a shift to the left of the concentration-response curve to oleamide and an increase in the magnitude of maximum vasodilation in rings with endothelium. Oleamide produced the maximal relaxant response at 10-5 M concentration. Conclusions: Oleamide has both in vivo and in vitro vasodilator effects. Vasodilator effects could be mediated by compounds synthesized/released by the endothelium (hyperpolarizing factor) or acting directly on vascular smooth muscle in aortic rings. The TRPV1 and CB1R receptors could mediate these effects. Finally, the results suggest that oleamide probably induces the synthesis/release of a vasoconstrictor prostanoid.

[Abdominal surgery in premature infants with patent ductus arteriosus]. / Cirugía abdominal en prematuros con persistencia de ductus arterioso.

INTRODUCTION: Patent ductus arteriosus (PDA) is considered a risk factor for necrotising enterocolitis (NEC) and other gastrointestinal complications in preterm infants. The aim of this study is to determine whether there is a higher incidence of abdominal surgery and the associated morbidity and mortality in preterm infants who require treatment due to a significant PDA. METHODS: An observational study was conducted that included preterm infants with <37 weeks of gestational age, and a diagnosis of PDA in the last 10 years. Depending on the treatment received, the patients were divided into 3 groups: medical (A), medical and surgical (B), and no treatment (C). An analysis was performed on the pre- and peri-natal variables, as well as the incidence of gastrointestinal complications (NEC, and need for surgery for this reason), and overall mortality. RESULTS: The study included a sample of 144 patients, of whom 91 were assigned to group A, 16 to B, and 37 to C. The mean gestational age by groups was 28, 26.7, and 30.1 weeks, respectively. The mean birth weight was 1083.9 gr, 909.3 gr, and 1471.2 gr, respectively. As regards the incidence of NEC, a total of 21, 5, and 5 cases, respectively, were found in each group, with 43%, 60% and 35%, respectively requiring abdominal surgery. Mortality by groups was 12%, 19%, and 3%, respectively CONCLUSION: Patients who required treatment for a significant PDA had a higher incidence of gastrointestinal complications and higher mortality than untreated patients, with no statistically significant differences being found. In the group of patients that required treatment, lower gestational age and birth weight, could explain the increase in morbidity and mortality found in these patients.

Effects of ranolazine on vasomotor responses of rat aortic rings.

BACKGROUND AND AIMS: Ranolazine is a piperazine derivative that was approved in 2006 for the treatment of chronic stable angina. Compared with first-line drugs currently used to treat angina, beneficial effects of ranolazine occur without changing hemodynamic parameters such as heart rate and blood pressure. In the present study the effects of ranolazine on vasomotor responses of rat aortic rings were examined. METHODS: Pharmacological evaluation was performed by analyzing the vasomotor responses of ranolazine on aortic rings of adult male Wistar rats precontracted with phenylephrine (10(-5) M). In each experiment we used a pair of rings (with and without endothelium) from the same aorta and superfused in the same bath. RESULTS: Ranolazine (10(-6)-10(-4) M) induced a concentration-dependent relaxation of phenylephrine-precontracted rings. The relaxation was only partially dependent on the presence of the endothelium (56.78 ± 6.81% in rings with endothelium and 47.88 ± 4.70% in rings without endothelium). In rings with endothelium, L-NAME induced a shift to the right of the concentration-response curve to ranolazine. Blocking the cyclooxygenase pathway induced a leftward shift of the concentration relaxation curve to ranolazine in both types of rings and increased the ranolazine-induced relaxation in rings without endothelium. CONCLUSIONS: Ranolazine has a vasodilatory effect that is predominantly endothelium-independent. The synthesis/release of nitric oxide by the endothelium may, however, contribute to its relaxing action. These effects of ranolazine may contribute to its beneficial effects in patients with stable angina.

Subwavenumber charge-coupled device spectrometer calibration using molecular iodine laser-induced fluorescence.

Spectrometers configured with charge-coupled devices (CCD) or other array-based detectors require calibration to convert from the pixel coordinate to a spectral coordinate. A CCD calibration method well suited for Raman spectroscopy has been developed based on the 514.5 nm Ar(+) laser-induced fluorescence (LIF) spectrum of room-temperature molecular iodine vapor. Over 360 primary and secondary I(2) LIF calibration lines spanning 510-645 nm were identified as calibrant peaks using an instrumental resolution of 1 cm(-1). Two instrument calibration functions were evaluated with these peaks: a second-order polynomial and a function derived from simple optomechanical considerations. The latter function provided better fitting characteristics. Calibration using I(2) LIF was tested with measurements of both laser light scattering and Raman spectra. The I(2) LIF reference spectra and the signal spectra were recorded simultaneously, with no cross talk, by separating the two signals spatially along the vertical axis of the CCD imager. In this way, every CCD image could be independently calibrated. An accuracy and a precision of +/-0.05 cm(-1) were achieved with this calibration technique.

Evaluación morfológica de brotes regenerados de callos de arroz (variedad IACuba-28) resistentes a higromicina / Morphological evaluation of shoots regenerated from hygromycin-resistant rice callus (cv IACuba-28)

Se estableció un sistema de evaluación de brotes de arroz regenerados de callos resistentes a higromicina, que permitió relacionar las características morfológicas de dichos brotes con su resistencia al antibiótico. Callos embriogénicos de arroz se transformaron con Agrobacterium tumefaciens (EHA105/ pCAMBIA1300),con el gen de la higromicina-fosfotransferasa como marcador de selección. Después de dos semanas en medio de cultivo con higromicina, los callos resistentes fueron transferidos a regeneración. Durante 30 días se realizaron extracciones sucesivas de brotes emitidos de los callos, en seis intervalos de cinco días cada uno. Estos brotes se clasificaron según su morfología en: clase I – brote vigoroso con una estructura bipolar típica, de ápice y raíz con longitudes proporcionales; clase II – brote con raíz pequeña respecto al ápice, o sin raíz; clase III – brote con alteraciones fenotípicas, albinismo, hojas muy anchas o enrolladas. Los brotes clasificados se transfirieron a medio MS con higromicina para evaluar su viabilidad. Los declase I, que predominaron en las primeras extracciones, presentaron la mayor viabilidad durante el enraizamiento y crecimiento del follaje. En las últimas dos extracciones ocurrió una drástica reducción de los brotes clase I, y aumentaron los de clases II y III, simultáneamente disminuyó la viabilidad de estos últimos en MS con higromicina. Este resultado puede aplicarse para mejorar la eficiencia de obtención de plantas transgénicas de arroz en estas condiciones, debido a que precisa el momento óptimo para lograr brotes con características morfológicas normales y que sean resistentes a higromicina.