Expression of adenosine 5'-monophosphate-Activated protein kinase (AMPK) in ovine testis (Ovis aries): In vivo regulation by nutritional state.

In the present study, we identified AMPK and investigated its potential role in steroidogenesis in vivo in the ovine testis in response to variation in nutritional status (fed control vs. restricted). We performed immunoblotting to show that both active and non-active forms of AMPK exist in ovine testis and liver. In testis, we confirmed these results by immunohistochemistry. We found a correlation between ATP (Adenosine-Triphosphate) levels and the expression of AMPK in liver. Also, low and high caloric diets induce isoform-dependent AMPK expression, with an increase in α2, ß1ß2 and γ1 activity levels. Although the restricted group exhibited an increase in lipid balance, only the triglyceride and HC-VLDL (Cholesterol-Very low density lipoprotein) fractions showed significant differences between groups, suggesting an adaptive mechanism. Moreover, the relatively low rate of non-esterified fatty acid released into the circulation implies re-esterification to compensate for the physiological need. In the fed control group, AMPK activates the production of testosterone in Leydig cells; this is, in turn, associated with an increase in the expression of 3ß-HSD (3 beta hydroxy steroid deshydrogenase), p450scc (Cholesterol side-chain cleavage enzyme) and StAR (Steroidogenic acute regulatory protein) proteins induced by decreased MAPK ERK½ (Extracellular signal-regulated kinase -Mitogen-activated protein kinase) phosphorylation. In contrast, in the restricted group, testosterone secretion was reduced but intracellular cholesterol concentration was not. Furthermore, the combination of high levels of lipoproteins and emergence of the p38 MAP kinase pathway suggest the involvement of pro-inflammatory cytokines, as confirmed by transcriptional repression of the StAR protein. Taken together, these results suggest that AMPK expression is tissue dependent.

Tetania neonatal por hipocalcemia secundaria a hipovitaminosis D. Forma extrema de una enfermedad que resurge / Neonatal hypocalcemic tetany due to vitamin D deficiency. Extreme form of a re-emerging disease

Desde el inicio de la era industrial, el raquitismo ha sido una enfermedad endémica. Con el descubrimiento de la vitamina D y el aporte de suplementos, sobre todo en las fórmulas lácteas infantiles, prácticamente había desaparecido, pero durante los últimos años parece haberse convertido de nuevo en un problema de salud pública. La carencia de vitamina D se asocia no sólo a problemas óseos, sino también a un importante incremento del riesgo de enfermedades cardiovasculares, autoinmunes, infecciosas y tumorales. Comunicamos un caso de tetania neonatal por hipocalcemia secundaria a hipovitaminosis D en un neonato de menos de 2 días de vida. La precocidad de la aparición y la gravedad clínica son excepcionales. Además, advierte del problema emergente que constituye el déficit de vitamina D y de la necesidad de instaurar la suplementación con ésta vitamina, siguiendo las últimas recomendaciones de la Asociación Española de Pediatría (AU)

Since industrial revolution, rickets has been an endemic disease. Since the discovery of vitamin D and its supplements, above all in milk formulates, practically it was disappear, but in the last few years it seems to be again a public health problem. Vitamin D deficiency contributes, not only to bone problems, but also to an important increase in the risk of cardiovascular, autoimmune, infectious diseases and cancer. We communicate a case of neonatal hypocalcemic tetany secondary to a vitamin D deficiency that appeared in a neonate before the second day of life. The precocity of its appearance and its clinical severity are exceptional. It also warn of the emergent problem that it suppose the vitamin D deficiency and the necessity of set up the supplementation with this vitamin, following the last recommendations of the Spanish Paediatrics Association (AU)

Radiobiological effect of 99mTechnetium-MIBI in human peripheral blood lymphocytes: ex vivo study using micronucleus/FISH assay.

99mTc-MIBI is currently used, for cardiac investigations, for parathyroid thyroid imaging and evaluation of various tumours. It has been demonstrated that 99mTc-MIBI is specifically taken up by the human peripheral blood lymphocytes (HPBL), cells which are known to be highly radiosensitive. To evaluate the possible chromosomal damage induced on HPBL by their in vitro exposure to increasing activities of 99mTc-MIBI and also to establish whether HPBL undergo apoptosis or necrosis after in vitro exposure to 99mTc-MIBI. Blood from two healthy donors were irradiated, incubated in vitro with increasing activities of 99mTc-MIBI corresponding to absorbed doses ranging from 1 microGy, 100 microGy, 1 cGy, 10 cGy, 50 cGy to 1 Gy. The cytokinesis block micronucleus (MN) assay was used and the frequency of binucleated cells (BN) with MN (MNBN) was analyzed in cultured HPBL (in either the G0- or G1- and S1-phase of the cell cycle). The fluorescence in situ hybridization (FISH) with pancentromeric probes was also applied to study the MN regarding whole chromosomes or acentric fragments. Apoptosis induction by 0.1 Gy of 99mTc-MIBI in HPBL was quantified using annexin-V test. The frequencies of MNBC were similar in control cultures and in HBPL cultures exposed to 1 microGy, 100 microGy and 1 cGy. However, they were significantly higher (P<0.05 versus controls and lower doses) after one treatment exposure to 0.25 mCi of 99mTc-MIBI (corresponding to 10 cGy) or more but the percentages of MNBN with 10 cGy, 50 cGy and 1 Gy did not differ significantly. The increase of MNBN was more pronounced (P<0.05) for cells irradiated during G1 phase than for those irradiated during G0 or S1. Using FISH, 80-90% of the MN were centromere negative. Although small, the absolute number of MN positive for centromeric signal and presumably containing whole chromosomes increased with doses. There is a statistically significant (P=0.001 and 0.006) increase of both apoptotic cells and necrosis, respectively, as compared to control cells in two times studied (24 and 36 h). Chromosomic damages can thus be demonstrated in HPBL after in vitro exposure of blood to at least 0.25 mCi of 99mTc-MIBI corresponding to one absorbed dose of 10 cGy, and for this dose, apoptosis and necrosis phenomenons were detected.

[Presinusoidal portal hypertension in post-hepatitis cirrhosis]. / Hypertension portale de type présinusoïdal au cours des cirrhoses post-hépatitiques.

Two cases of very probable post-hepatitis cirrhosis are presented. Both were complicated by presinusoidal portal hypertension (P. H. T.), the peroperative portal pressures measured directly being much higher than the wedged hepatic venous pressures. Although post-sinusoidal P. H. T. is the usual complication of most types of cirrhosis, these two cases support recent studies reporting the possibility of pre-sinusoidal P. H. T. in post-hepatitis cirrhosis. The wedged hepatic venous pressure is not a reliable indicator of portal pressure in these cases. The presence of presinusoidal P. H. T. does not exclude the diagnosis of cirrhosis but makes that of alcoholic cirrhosis very unlikely.