Synthesis and evaluation of 5-aminosalicyl-glycine as a potential colon-specific prodrug of 5-aminosalicylic acid

OBJECTIVE: To estimate more precisely the risk of fetal loss and congenital abnormalities after maternal parvovirus B19 infection, and to assess the long term outcome for surviving infants. DESIGN: Prospective cohort study of pregnant women with confirmed B19 infection with follow up of the surviving infants. The rate of fetal loss in the study cohort was compared with that in pregnant women with varicella. SETTING: Cases reported by laboratories in England and Wales between 1985-1988 and 1992-1995. SAMPLE: Four hundred and twenty-seven pregnant women with B19 infection and 367 surviving infants of whom 129 were followed up at 7-10 years of age. METHODS: Questionnaires to obstetricians and general practitioners on outcome of pregnancy and health of surviving infants. Maternal infection confirmed by B19-specific IgM assay and/or IgG seroconversion. RESULTS: The excess rate of fetal loss in women with B19 infection was confined to the first 20 weeks of gestation and averaged 9%. Seven cases of fetal hydrops followed maternal infections between 9 and 20 weeks of gestation (observed risk 2.9%, 95% CI 1.2-5.9). No abnormalities attributable to B19 infection were found at birth in surviving infants (observed risk 0%, upper 95% CI 0.86%). No late effects were found at 7-10 years. CONCLUSIONS: Around 1 in 10 women infected before 20 weeks of gestation will suffer a fetal loss due to B19. The risk of an adverse outcome of pregnancy after this stage is remote. Infected women can be reassured that the maximum possible risk of a congenital abnormality due to B19 is under 1% and that long term development will be normal.     

Temporal relationship between progestin and luteinizing hormone concentrations in pseudopregnant rats treated with prostaglandin-F2 alpha

The temporal changes in progesterone (delta 4P), 20 alpha-dihydroprogesterone (20 alpha-DHP) and luteinizing hormone (LH) concentrations in pseudopregnant (PSP) rats after treatment with a single subcutaneous Silastic-PVP tube containing 600 micrograms PGF2 alpha were correlated. Progesterone levels fell and LH levels rose significantly 2h after initiation of treatment, while 20 alpha-DHP levels were found to increase significantly 12h after treatment. Since the changes in delta 4P and LH concentrations occurred concurrently, it seems that the increase in LH levels could have been due to a direct effect of PGF2 alpha on the ovary causing a reduction in delta 4P and thus a negative feedback effect on LH release. Alternatively, PGF2 alpha might exert a direct effect on LH secretion at the hypothalamic-pituitary level.     

Efficient Monitoring Algorithm for Fast News Alerts

Recently, there has been a dramatic increase in the use of XML data to deliver information over the Web. Personal Weblogs, news Web sites, and discussion forums are now publishing RSS feeds for their subscribers to retrieve new postings. As the popularity of personal Weblogs and RSS feeds grows rapidly, RSS aggregation services and blog search engines have appeared, which try to provide a central access point for simpler access and discovery of new content from a large number of diverse RSS sources. In this paper, we study how the RSS aggregation services should monitor the data sources to retrieve new content quickly using minimal resources and to provide its subscribers with fast news alerts. We believe that the change characteristics of RSS sources and the general user access behavior pose distinct requirements that make this task significantly different from the traditional index refresh problem for Web search engines. Our studies on a collection of 10,000 RSS feeds reveal some general characteristics of the RSS feeds and show that, with proper resource allocation and scheduling, the RSS aggregator provides news alerts significantly faster than the best existing approach.