Transformation of fatty acid hydroperoxides by alkali and characterization of products

It has previously been determined that (13S,9Z,11E)-13-hydroperoxy-9,11-octadecadienoic acid was mainly converted into (13S,9Z,11E)-13-hydroxy-9,11-octadecadienoic acid by 5 N KHO with preservation of the stereochemistry of the reactant [Simpson, T.D., and Gardner, H.W. (1993)Lipids 28, 325–330]. In addition, about 20–25% of the reactant was converted into several unknown by-products. In the present work it was confirmed that the stereochemistry was conserved during the hydroperoxy-diene to hydroxydiene transformation, but also, novel by-products were identified. It was found that after only 40 min reaction (9Z)-13-oxo-trans-11,12-epoxy-9-octadecenoic acid accumulated to as much as 7% of the total. Later, (9Z)-13-oxo-trans-11,12-epoxy-9-octadecenoic acid began to disappear, and several other compounds continued to increase in yield. Two of these compounds, 2-butyl-3,5-tetradecadienedioic acid and 2-butyl-4-hydroxy-5-tetradecenedioic acid, were shown to originate from (9Z)-13-oxo-trans-11,12-epoxy-9-octadecenoic acid, and they accumulated up to 2–3% each after 4 to 6 h. Some other lesser products included 11-hydroxy-9,12-heptadecadienoic acid, 3-hydroxy-4-tridecenedioic acid, 13-oxo-9,11-octadecadienoic acid and 12,13-epoxy-11-hydroxy-9-octadecenoic acid. Except for the latter two, most or all of the compounds could have originated from Favorskii rearrangement of the early product, (9Z)-13-oxo-trans-11,12-epoxy-9-octadecenoic acid, through a cyclopropanone intermediate.     

Steroidogenesis in bovine granulosa cells: the effect of short-term changes in dietary intake

The nutritional status of a cow is a key factor in the regulation of both follicle growth and oocyte quality. In this study, the effect of diets designed to increase circulating insulin and insulin-like growth factor I (IGF-I) concentrations on steroid production by granulosa cells in vitro was examined to analyse the mechanisms through which these changes occur. Hereford x Friesian heifers (n = 24) were offered maintenance or twice maintenance diets during the experimental period (17 days). Circulating concentrations of FSH did not differ between the two dietary groups, whereas insulin and IGF-I concentrations showed significant diet x day of oestrous cycle interactions. Ovaries were collected on day 3 of the first follicle wave after synchronization of oestrus. Granulosa cells were isolated from small (1-4 mm) and medium-sized (4-8 mm) follicles and cultured in the presence of long R3-IGF-I or bFSH or both. After 4 days in culture, granulosa cells isolated from small follicles, but not medium-sized follicles, collected from cattle offered the twice maintenance diet secreted significantly higher (P < 0.05) amounts of oestradiol compared with granulosa cells collected from cattle offered the maintenance diet. The effect was apparent in either the presence or absence of FSH and long R3-IGF-I. This nutritional effect on aromatase activity in granulosa cells was not apparent after day 6 of culture. There was no effect of diet on progesterone production by granulosa cells after 4 or 6 days of culture. These results support the hypothesis that dietary-induced changes in circulating insulin and IGF-I concentrations have a direct effect on the steroidogenic potential of bovine granulosa cells from small follicles. The dietary-induced increases in aromatase activity in small follicles combined with the increased concentration of metabolic hormones are possible mechanisms through which short-term changes in nutrition may affect follicle dynamics.     

Ethnic stereotypes: The significance of consensus.

Investigated whether the degree of consensus in trait attribution to ethnic groups has any particular meaning to the individual. Canadian 9th and 12th graders (n = 36) were presented with traits previously found in the stereotypes about different groups, and asked to identify the ethnic group so characterized. 3 independent variables were manipulated: consensus of the attributes, age of the Ss, and the number of attributes presented. Dependent variables included the accuracy and the perceived difficulty of identification. Results indicate that the degree of consensus in the stereotype had considerable information value to the Ss. This suggests that stereotypes generally develop from information available to a community, and that the consensus noted in stereotype assessment procedures reflects the consistency of this information. (French summary) (16 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The MAGNeT Toolkit: Design, Implementation and Evaluation

The current trend in constructing high-performance computing systems is to connect a large number of machines via a fast interconnect or a large-scale network such as the Internet. This approach relies on the performance of the interconnect (or Internet) to enable fast, large-scale distributed computing. A detailed understanding of the communication traffic is required in order to optimize the operation of the entire system. Network researchers traditionally monitor traffic in the network to gain the insight necessary to optimize network operations. Recent work suggests additional insight can be obtained by also monitoring traffic at the application level. The Monitor for Application-Generated Network Traffic toolkit (MAGNeT) we describe here monitors application traffic patterns in production systems, thus enabling more highly optimized networks and interconnects for the next generation of high-performance computing systems.     

Fatal gastrointestinal haemorrhage due to coexisting primary aorto-enteric and aorto-colic fistulae. Complicating untreated atheromatous abdominal aortic aneurysm

We report a case of aorto-enteric and aorto-colonic fistulae in a 73 year old man with no previous abdominal surgery which resulted in massive gastrointestinal haemorrhage and death and was undiagnosed despite several hospital admissions and endoscopic examinations. This case serves to highlight an extremely rare but fatal condition, which is potentially treatable, if an early diagnosis is made.     

THE MECHANISM OF GUSHING—A REVIEW

Gushing is reviewed with particular attention to the nucleole theory. Evidence derived from phenomena comparable with gushing occurring in fields unrelated to brewing is discussed.