Sex-related differences in cardiovascular responses to common carotid occlusion in conscious rats

Mean arterial pressure and heart rate were determined in conscious, unrestrained groups of 10 male, female and androgenized female Wistar rats 20 s (early pressor response) and 1 min (late sustained response) after bilateral carotid artery occlusion. The early pressor response, which is carotid reflex origin, was 40% greater in female than in male rats (45 ñ 2 vs 63 ñ 3 mmHg, respectively). The late sustained response, which is of central origin (probably ischemic), did not differ between male and female rats (32 ñ 2 vs 37 ñ 4 mmHg, respectively). The magnitude of the early pressor response of androgenized female rats (50 ñ 2 mmHg) was similar to that of male rats (45 ñ 2 mmHg) but the late sustained response was 19% smaller (26 ñ 2 mmHg). Common carotid occlusion caused increases in haert rate which were greater in female (51 ñ 9 and 34 ñ 9 beats/min in the early pressor response and late sustained response respectively) than in male rats (31 ñ 5 and 8 ñ 4 beats/min, respectively). In androgenized female rats, heart rate decreased during common carotid occlusion (34 ñ 7 and 35 ñ 8 beats/min after 20 s and 1 min, respectively). These data provide evidence that there are substantial sex-related differences in the cardiovascular responses to common carotid occlusion in conscoious rats and indicate that administration of androgens to newborn female rats affects the baroreceptor reflex control of their arterial pressure

El sueño dorado / The gilding dream

Ciento setenta y uno pacientes (82 por ciento) de un total de 209 fueron estudiados utilizando los indicadores A.P.A.C.H.E.II, T.I.S.S. y el índice porcentual de mortalidad al ingreso y alta del paciente. La edad promedio fue de 52 (16-92) años, siendo 130 (76 por ciento) hombres y 41 (24 por ciento) mujeres; considerando la condición diagnóstica previa a admisión obtuvimos 139 (81 por ciento) pacientes "médicos" y 32 (19 por ciento) "post-quirúrgicos". La mortalidad real obtenida fue el doble de la mortalidad estimada y el 60 por ciento de los pacientes dados en alta alcanzaron por lo menos una recuperación parcial.

Sex-related differences in the analgesic response to the rat tail immersion test

The analgesic response was evaluated by the tail immersion test in adult male (N = 30), female (N = 21) and androgenized female Wistar rats (N = 15). The reaction time for tail withdrawal from the hot water bath was faster for male than for female rats (3.48 +/- 0.12 vs 6.46 +/- 0.42 s). The reaction time of androgenized female rats was similar to that of male rats (3.08 +/- 0.16 s). Blockade of opiate receptors with naloxone (2 mg/kg, ip) decreased the sensitivity to the noxious stimuli in males (4.08 +/- 0.10 s) and in androgenized females (3.69 +/- 0.19 s) but increased it in female rats (5.01 +/- 0.41 s). These data show sex-related differences in the analgesic response evaluated by the tail immersion test and indicate that administration of androgens to newborn female rats affects their pain sensitivity.

Análise in vitro da microinfiltraçäo marginal em cavidades de classe V restauradas com três diferentes sistemas adesivos / In vitro marginal microleakage evaluation in class V cavities, restored with three different bonding systems

Análise "in vitro" da microinfiltraçäo marginal em cavidades de classe V confeccionadas nas faces vestibular e lingual de terceiros molares humanos recém extraídos, restauradas com regina composta de micropartícula Silux Plus (3M) utilizando 3 marcas diferentes de sistemas adesivos: Paama 2 (SDI), One-Step (Bisco) e Clearfil Liner Bond 2 (Kuraray). Os dentes foram termociclados e para análise da microinfiltraçäo foram imersos durante duas horas em soluçäo de nitrato de prata à 50 por cento. Como resultado obtivemos que todos os sistemas adesivos praticamente evitaram a microinfiltraçäo nas margens oclusais, porém nas cervicais nenhum deles foi capaz de inibir a microinfiltraçäo. A microinfiltraçäo ocorreu em maior grau na parede cervical, quando comparada com a aclusal

Participation of opioid receptors in the modulation of the analgesic response by adrenal and gonadal glands

The invovlement of opiodi receptors in the analgesic response was evaluated by the tail-immersion test in simultaneously adrenalectomized and ovariectomized female Wistar rats (210-250g). The reaction time (mean ñ SEM) for tail withdrawal from hot water decreased significantly 2 weeks after surgery (3.52 ñ 0.20 s) when compared to intact animals (6.09 ñ 0.23 s). Hormonal replacement with dexamethasone (50*/day) did not affect reaction time (3.38 ñ 0.19 s). However, this response was restored by combined adrenal and gonadal steroid substitution (estradiol 5*g/day and progesterone 1.5*g 6h before the test) therapy (5.11 ñ 0.45 s) in animal treated with dexamethasone plus estradiol and 5.04 ñ 0.43 s in animals treated with dexamethasone plus estradiol plus progesterone). Naloxone (2mg/Kg decreased the reaction time of animals treated with adrenal and gonadal steroids (5.11 ñ 0.45 vs 4.15 ñ 0.44 and 5.04 ñ 0.43 vs 3.87 ñ 0.28 s, respectively, before and after naloxone) but failed to decrease it in rats treated with dexamethasone only (3.88 ñ 0.18 vs 4.34 ñ 0.25 s, before and after naloxone). These observations indicate that gonadal steroids are the most important steroid factors involved in the reaction time to tail immersion in hot water and confirm other reports that the opioid pathways modulating the neuronal circuitry require the presence of these hormones