Role of cell wall polysaccharides in water distribution during seed imbibition of Hymenaea courbaril L.

Seed water imbibition is critical to seedling establishment in tropical forests. The seeds of the neotropical tree Hymenaea courbaril have no oil reserves and have been used as a model to study storage cell wall polysaccharide (xyloglucan - XyG) mobilization. We studied pathways of water imbibition in Hymenaea seeds. To understand seed features, we performed carbohydrate analysis and scanning electron microscopy. We found that the seed coat comprises a palisade of lignified cells, below which are several cell layers with cell walls rich in pectin. The cotyledons are composed mainly of storage XyG. From a single point of scarification on the seed surface, we followed water imbibition pathways in the entire seed using fluorescent dye and NMRi spectroscopy. We constructed composites of cellulose with Hymenaea pectin or XyG. In vitro experiments demonstrated cell wall polymer capacity to imbibe water, with XyG imbibition much slower than the pectin-rich layer of the seed coat. We found that water rapidly crosses the lignified layer and reaches the pectin-rich palisade layer so that water rapidly surrounds the whole seed. Water travels very slowly in cotyledons (most of the seed mass) because it is imbibed in the XyG-rich storage walls. However, there are channels among the cotyledon cells through which water travels rapidly, so the primary cell walls containing pectins will retain water around each storage cell. The different seed tissue dynamic interactions between water and wall polysaccharides (pectins and XyG) are essential to determining water distribution and preparing the seed for germination.

Double-outlet right ventricle associated with discordant atrioventricular connection and dextrocardia in a cat.

The prevalence of congenital cardiac disease in cats varies from 0.2 to 1 per cent, with males being more affected than females. This is probably an underestimate due to the fact that not all affected kittens are presented. Discordant atrioventricular connection (where the morphological right atrium connects to the morphological left ventricle, and the morphological left atrium connects to the morphological right ventricle) is an uncommon condition in humans and, to the authors' knowledge, has not to date been described in animals. The association between this anomaly and the double-outlet right ventricle (where both great arteries arise entirely or partially from the morphological right ventricle) is extremely rare in children. This report describes a case of a cat which presented with this association of cardiac defects.

Prolapso de uretra em cão da raça maltês. Relato de caso

O artigo não apresenta resumo.

Acute poisoning with methidathion: a case.

An acute poisoning in a 50-year-old man who ingested approximately 6.2 g of the phosphorus ester methidathion is described. The patient was treated with three haemoperfusions 23, 44 and 115 h after ingestion, with continuous gastric lavage, atropine and pralidoxime administration and with prolonged mechanical ventilation. Haemoperfusion was an ineffective epuration technique since it removed only 0.22% of the ingested methidathion. The clinical course wavered because of a probable redistribution of phosphorus ester from fat to blood. A plasma level higher than 100 micrograms l-1 was associated with the most serious phases. Methidathion was present in the plasma until the sixth day, in the urine until the seventh and in the gastric juice until the eighth. Its absence in the fat biopsy made on the tenth day was an aid to therapy. The phosphorus ester did not inhibit lymphocyte neuropathy target esterase (NTE), neither did it induce development of delayed polyneuropathy.

[Computerized determination of pharmacokinetic constants in a biocompartmental model aimed at the optimal clinical use of drugs]. / Determinazione computerizzata delle costanti farmacocinetiche in un modello bicompartimentale finalizzata ad un impiego clinico ottimale dei farmaci.

On the basis of sodium Naproxene plasma wash-out curve a computerized system to obtain pharmacokinetic constants in an open bi-compartment model is described. The system could be used to optimize and enhance drug administration in clinics and anaesthesiology.