Female sex steroid induced epithelial changes in the gallbladder of the ovariectomized Syrian hamster.

Ovariectomized Syrian hamsters treated by female sex steroids during a 1-month period show gallbladder surface epithelial changes in the fundic area consistent with apical bulging and decapitations of the epithelial cells. These events were detected in the infundibulum and the fundic or body regions of estrogen- and estrogen+progesterone-treated hamsters. In control hamsters, these events were restricted to the region in the vicinity of the bile duct. Following steroid treatment, intraluminal deposits detected resembled Ca-bilirubinate deposits described in previous studies while decapitations are similar to endometrial epithelium changes associated with hormonal physiological changes or treatments. Moreover some small electron-dense deposits are comparable to those found in human cholesterol gallstones. This report indicates that, besides an alteration in bile composition, cell fragments originating from the surface epithelium of the bile duct and/or of the gallbladder mucosal epithelium could participate in gallstone nucleation.     

Lipids of Angiostrongylus cantonensis (Nematoda: Metastrongyloidea): a comparison between young adults and gravid worms

1. All major classes of lipids were found in the young adults in brain (22 days post-infection) and gravid Angiostrongylus cantonensis in lung of rats (34 days post-infection) comprising approximately 60% of phospholipids, 30% of neutral lipids and the rest, glycolipids. 2. The relative composition of phospholipids were quite similar between worms from the two different habitats, with phosphatidylcholine predominating. The glycolipid profiles were also similar. 3. More neutral lipids in the worms from brain existed as cholesterol and cholesterol esters than those from the lung. More than 20% of the fatty acids in these lipids of the brain were found as C10-C14 acids while oleic acid was the main component in the lung worm.     

Indication of dynamic neurovascular coupling from inconsistency between EEG and fMRI indices across sleep–wake states

Sleep and Biological Rhythms - Neurovascular coupling (NVC), the transient regional hyperemia following the evoked neuronal responses, is the basis of blood oxygenation level-dependent techniques...     

Triiodothyronine effect on some parameters of carbohydrate metabolism in rat blood and liver. I. In vivo effect of triiodothyronine on liver glycogen content, blood metabolites and serum glycogenolytic activity

Short (7 days) T3-treatment has no influence on the plasma glucose and FFA concentration and blood lactate level, as well as on the hepatic glycogen content in the rats. The rise in T3 levels, observed in our study, was accompanied by a fall in T4 concentrations, indicating suppression of the endogenous T4 production. On the other hand, glycogenolytic activity of rat serum in vitro is the highest in the system: control liver slices-serum of rats pretreated with T3 as compared to the system: control liver slices-control serum. These observations may lead to conclusions, that serum of rats pretreated with T3 contains factors exhibiting the greater ability to mobilize glucose from liver slices than the control serum (euthyroid). The possibility, that pretreatment with T3 may cause a decrease in the number and/or affinity of beta-adrenergic receptors in the rat liver, is discussed.     

Morphological pathway of flagellar assembly in Salmonella typhimurium.

The process of flagellar assembly was investigated in Salmonella typhimurium. Seven types of flagellar precursors produced by various flagellar mutants were purified by CsCl density gradient protocol. They were characterized morphologically by electron microscopy, and biochemically by two-dimensional gel electrophoresis. The MS ring is formed in the absence of any other flagellar components, including the switch complex and the putative export apparatus. Four proteins previously identified as rod components, FlgB, FlgC, FlgF, FlgG, and another protein, FliE, assemble co-operatively into a stable structure. The hook is formed in two distinct steps; formation of its proximal part and elongation. Proximal part formation occurs, but elongation does not occur, in the absence of the LP ring. FlgD is necessary for hook formation, but not for LP-ring formation. A revised pathway of flagellar assembly is proposed based on these and other results.