Phylogeny and toxicological assessments of two Porthidium lansbergii lansbergii morphotypes from the caribbean region of Colombia.

After a snakebite accident, species identification is of vital importance. However, the existence of intraspecific differences in the body coloration patterns of venomous snakes can generate confusion and delay a convenient and effective treatment. This is the situation for Porthidium lansbergii lansbergii from Colombia, for which two distinctive color morphs occur, and the relationship of these morphs with venom toxicity is unknown. Therefore, venom samples from specimens of these two morphs were collected from the Colombian Caribbean region, and their protein profiles compared. Likewise, their venom functional activities were evaluated in vitro and in vivo in BALB/C mice. Additionally, using sequences of the mitochondrial cytochrome b (Cyt-b) gene, the relationship between these Colombian P. lansbergii lansbergii morphotypes was investigated, and their phylogenetic positions were determined for the first time using Bayesian inference. Despite the noticeable coloration divergence between the individuals analyzed, similar protein profiles of their venoms were observed. Additionally, neither their lethality nor biochemical activities were notably different. In general, both venoms were highly proteolytic, lacked a coagulant effect in vitro, and extended the clotting time due to the action of venom components, such as disintegrins and proteases, that induce defibrination. These results agreed with the result of our phylogenetic analysis, suggesting that the two chromatic morphs do not represent isolated populations. The phylogenetic analyses also supported the currently recognized P. lansbergii lansbergii subspecies as a monophyletic complex. In conclusion, the results of this investigation suggest similar clinical manifestations regardless of body coloration after a P. lansbergii lansbergii envenomation, and pools can therefore be used for antivenom development, medical treatments, and further research efforts.

Calcium homeostasis during pregnancy and lactation in Brazilian women with low calcium intakes: a longitudinal study.

BACKGROUND: Physiologic adjustments in calcium homeostasis during pregnancy and lactation in women with marginal calcium intakes have not been described. OBJECTIVE: The objective was to examine longitudinal changes in various aspects of calcium homeostasis during pregnancy and lactation in 9 healthy Brazilian women who habitually consumed approximately 500 mg Ca/d. DESIGN: Calcium homeostasis was assessed at 3 time points: 10-12 (early pregnancy, EP) and 34-36 (late pregnancy, LP) wk of pregnancy and 7-8 wk postpartum (early lactation, EL). At each time point, the following variables were measured: dietary calcium intake with a 3-d weighed food record, 24-h urinary calcium excretion (UCa), intestinal calcium absorption (%CaAbs) via administration of stable calcium isotopes with a breakfast meal, serum 1,25-dihydroxyvitamin D, parathyroid hormone (PTH), insulin-like growth factor I (IGF-I), and biochemical markers of bone turnover. RESULTS: Dietary calcium did not change during the study. %CaAbs increased from 69.7 +/- 5.4% ( +/- SEM) during EP to 87.6 +/- 4.5% during LP (P < 0.05) and returned to 65.1 +/- 6.2% during EL. Compared with EP, UCa decreased 22% during LP and 68% during EL (P < 0.05). The net mean change in calcium retention was 212 mg/d during LP and 182 mg/d during EL. Several significant associations were found between the main outcome variables (%CaAbs, UCa, and markers of bone turnover) and serum hormones, especially IGF-I and PTH. CONCLUSIONS: Calcium homeostasis appears to be attained by a more efficient intestinal calcium absorption during pregnancy and by renal calcium conservation during both pregnancy and lactation. IGF-I and PTH seem to play major roles in the adjustment of calcium metabolism during pregnancy and lactation.

Intolerancia a la lactosa: la leche como instrumento de evaluacion / Lactose intolerance: milk as evaluation tool

Con el animo de conocer la incidencia de tolerancia a la lactosa y estudiar la posibilidad del empleo de la leche para tal fin, la administramos a un centenar de adultos sanos. Enciontramos que el 10% de ellos no presento senales de intolerancia y ademas mostri aumentos de la glicemia superiores a 20mg/dl. Estos resultados sugieren tolerancia ya que se reprodujeron al administrar glucosa libre a un grupo de referencia que, en cambio, si mostro sintomas de intolerancia cuando recibio lactosa. Se concluye que una dosis de leche, 400ml que contiene 50 g de lactosa, la medida de glicemia 45 minutos despues y el registro de las senales de intolerancia, son utiles para descubrir a los sujetos lactasa deficientes los cuales representan el 90% del grupo estudiado