5 children with hypokalemia, hypomagnesemia and hypocalciuria (Gitelman syndrome) in one family

Gitelman's syndrome was diagnosed in five siblings. The parents were relatives in the third remove. Gitelman's syndrome is a rare autosomal recessive hereditary magnesium reabsorption defect in the distal tubule. It is characterized by episodes of muscle weakness, usually accompanied by abdominal pain and vomiting. Tetany may occur during a febrile illness. Patients are of normal height and weight and have normal blood pressures. Sometimes eczematous skin lesions are found. Biochemically there is hypokalaemia, hypomagnesaemia and alkalosis. Urinary excretion rates of potassium and magnesium are elevated, the excretion of calcium is diminished. Treatment consists of oral suppletion of magnesium, sometimes also with oral potassium. A potassium-sparing diuretic may be used. The prognosis appears to be good.     

Time course of the effects of different cannabimimetics on prolactin and gonadotrophin secretion: evidence for the presence of CB1 receptors in hypothalamic structures and their involvement in the effects of cannabimimetics

Several reports have demonstrated that (-)-delta9-tetrahydrocannabinol (delta9-THC) and arachidonylethanolamide [anandamide (AEA)] were able to inhibit prolactin (PRL) secretion from the anterior pituitary gland in male rodents, whereas ovarian phase-dependent effects were seen in females. However, in most of these studies, the analysis of PRL levels was performed at times longer than 30 min after cannabinoid administration. In the present study, we examined the time course of the effects of three different cannabimimetics, delta9-THC, AEA, and AM356 (R-methanandamide), a more stable analog of AEA, on PRL and gonadotrophin secretion in male Wistar rats. In addition, we characterized the presence of cannabinoid receptors in hypothalamic structures related to neuroendocrine control and studied their potential involvement in the effects of cannabimimetics. We found that the three compounds decreased plasma luteinizing hormone (LH) levels, although only the effects of delta9-THC were statistically significant. The inhibitory effect was already apparent at 40 min after administration, but only in the case of delta9-THC did it persist up to 180 min after administration. No significant changes were seen in plasma follicle-stimulating hormone (FSH) levels after the administration of any of the three different cannabimimetics at any of the four times analyzed. Both AEA and AM356 produced a significant decrease in plasma PRL levels, which appeared at 20 min after administration and persisted up to 60 min, waning after this time. Interestingly, the time course of the effect of delta9-THC resembled that of AEA and AM356 only during the later part of the response, because delta9-THC produced a marked increase in plasma PRL levels at 20 min, no changes at 40 min and a decrease from 60 min up to 180 min. In additional experiments, we tried to elucidate which of these two phases observed after delta9-THC administration was mediated by the activation of cannabinoid receptors. These receptors are present in hypothalamic structures related to neuroendocrine control, with the highest densities in the arcuate nucleus (dorsal area) and the medial preoptic area, and the lowest in the lateral hypothalamic area, although none of these regions exhibited high densities for this receptor as compared with classical regions containing cannabinoid receptors, such as the basal ganglia. The activation of these receptors by delta9-THC seems to be involved in the inhibitory phase of the effect of this cannabinoid on PRL release, but not in the early stimulation; when these receptors were blocked with a specific antagonist, SR141716, the stimulation by delta9-THC was still observed, but the late inhibition was abolished. In summary, AEA and AM356 markedly decreased PRL release and slightly decreased LH secretion, with no changes on FSH release. delta9-THC also produced a marked inhibition of LH secretion, but its effects on PRL were biphasic with an early stimulation not mediated by the activation of cannabinoid receptors, followed by a late and cannabinoid receptor-mediated inhibition. Their site of action may well be the hypothalamic structures related to neuroendocrine control, which contain a small, but probably very active, population of cannabinoid receptors.     

Adenovirus-mediated transfer of a dominant-negative H-ras suppresses neointimal formation in balloon-injured arteries in vivo

Sixteen Holstein cows in midlactation were used in a design based on a replicated 4 x 4 Latin square with the last period removed to determine the influence of particle size of beet pulp neutral detergent fiber (NDF) on its effectiveness as a replacement for alfalfa NDF. Diets were a low forage, low fiber diet [12.1 g of alfalfa NDF/100 g of dry matter (DM)], a normal forage diet (low forage plus 7.8 g of additional alfalfa NDF/100 g of DM), and two low forage diets with 5.3 g of NDF/100 g of DM from either whole or finely ground dried sugar beet pulp. Replacement of alfalfa fiber with beet pulp fiber increased milk protein yield because of the tendencies toward increased milk yield and protein concentration. However, milk fat concentration and yield were unaffected. The addition of beet pulp fiber, either whole or ground, to the basal low forage, low fiber diet did not affect yields of milk, protein, or fat, but milk protein concentration tended to be lower for cows fed the beet pulp diets than for cows fed the basal diet. Reducing the particle size of beet pulp increased DM intake but did not affect any of the milk yield measurements. Particle size reduction of beet pulp did not reduce its effectiveness as a fiber source as measured by changes in milk fat content.     

Biological correlates of behavioral development in the ant, Novomessor albisetosus (Mayr).

Physical changes are associated with temporal polyethism, the division of labor according to age. The period of developing ovaries corresponds with the age when workers are found with the brood and queen. Resorption of ovaries occurs at a time when workers no longer tend brood and queen. Two bursts of exoskeleton hardening and growth of the poison gland apparatus corresponds with a transitional period in the behavioral development of workers and finally with their development into nest defenders and foragers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)