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The hepatobiliary disposition of thyroxine (T4) was evaluated in Groningen Yellow transport deficient (TR−) rats lacking functional multidrug resistance–associated protein 2 (Mrp2; Abcc2). Male Wistar and TR− rats were dosed orally (4 days) with phenobarbital (PB; 100 mg/kg) or DMP 904 (200 mg/kg), after which T4 homeostasis and hepatic cytochromes P450, UDP-glucuronosyltransferase, xenobiotic transporters, and T4 glucuronidation were determined. Serum concentrations of T4 were approximately 50% higher in control TR− rats than Wistars. PB and DMP 904 increased hepatic levels of P450s and T4-glucuronidation (T4-G), and these changes were associated with decreased serum T4 levels in both strains. In Wistar but not TR− rats, DMP 904 increased thyroid stimulating hormone levels twofold. Hepatobiliary clearance of T4 was determined after intravenous infusion of [125I]T4 to rats dosed with PB and DMP 904 (4 days). PB and DMP 904 increased plasma clearance and hepatic uptake of [125I]T4 equivalents in Wistar but not TR− rats. Total biliary clearance (Clbile) was approximately 0.85 and 0.2 ml/h in Wistar and TR− rats, respectively, with virtually no T4-G excreted in bile in TR− rats. Biliary clearance of unconjugated T4 was also lower in control TR− rats than in Wistars, although DMP 904 increased its biliary clearance in both strains. These results suggest that Mrp2 is likely to be responsible for biliary excretion of T4-G and contributes in part to excretion of T4. Decreased biliary clearance of T4 and metabolites in TR− rats mitigated but did not prevent drug-induced changes in serum T4, suggesting that other factors contribute to changes in T4 homeostasis in these rats. [ABSTRACT FROM AUTHOR]

Abstract  The origin and ancestry for Egyptian clover, Trifolium alexandrinum, was examined using AFLP data. The data support a close relationship of T. alexandrinum accessions from Syria and Egypt to T. apertum, T. berytheum, and T. salmoneum. However, crossability and geographic distributions suggest that T. apertum is an unlikely progenitor. In contrast, T. salmoneum appears to be the most probable progenitor for Syrian material of Egyptian clover, although a close relationship to T. berytheum was also revealed. The ability of these species to cross freely indicates that T. salmoneum and T. berytheum may be regarded as the primary ancestors from, which man domesticated Egyptian clover through artificial selection in Syria. Following domestication, the earlier forms of the crop species could have been taken into rain-fed cultivation in Palestine and irrigated cultivation in Egypt. In this regard, the domestication of Egyptian clover may be analogous to other crops, such as barley and wheat, which were also domesticated in the Fertile Crescent and taken into cultivation in the Nile Valley. It appears that genetic improvement of the crop occurred in Egypt after cultivation, and that the varieties that were developed in Egypt were later distributed worldwide. [ABSTRACT FROM AUTHOR]

Cerebral palsy (CP) can occur in term infants with or without preceding newborn encephalopathy. We compared the type and severity of CP and associated disability in these two groups. Participants from a population-based case-control study of term newborn encephalopathy were followed up for 6 years and linked to the Western Australian Cerebral Palsy Register. The remaining term infants with CP for the same period were also identified from the Cerebral Palsy Register. 13% of neonatal survivors of term newborn encephalopathy had CP, a rate of 116 per 1000 term live births. Overall, 24% of term infants with CP followed newborn encephalopathy. CP following newborn encephalopathy was more likely to: affect males (72% vs 56%); be severe (47% vs 25%); and be of spastic quadriplegia or dyskinetic types. Cognitive impairment was more common (75% vs 43%) and severe (41% vs 16%), as was epilepsy (53% vs 29%) in survivors of encephalopathy. These children were also more likely to: be non-verbal (47% vs 22%); have a severe composite disability score (47% vs 26%); and die between time of diagnosis of CP and age 6 years (5-year cumulative mortality 19% vs 5%). Children born at term who develop CP following newborn encephalopathy have a poorer prognosis than those with CP who were not encephalopathic in the first week of life. [ABSTRACT FROM AUTHOR]

Focuses on violence in schools, speculating on the relationship between student this type of violence and principals' leadership behaviors. Reference to the contents of literature on school violence; Relation between principals' behavior and school climate violence; Results of reasearch by the United States National Research Council.

Disk winds are thought to play a critical role in star birth. As winds extract excess angular momentum from accretion disks, matter in the disk can be transported inward to the star to fuel mass growth. However, observational evidence of wind carrying angular momentum has been very limited. We present Submillimeter Array (SMA) observations of the young star MWC 349A in the H26α and H30α recombination lines. The high signal-to-noise ratios made possible by the maser emission process allow us to constrain the relative astrometry of the maser spots to milli-arcsecond precision. Previous observations of the H30α line with the SMA and the Plateau de Bure interferometer (PdBI) showed that masers are distributed in the disk and wind. Our new high-resolution observations of the H26α line reveal differences in spatial distribution from that of the H30α line. H26α line masers in the disk are excited in a thin annulus with a radius of about 25 au, while the H30α line masers are formed in a slightly larger annulus with a radius of 30 au. This is consistent with expectations for maser excitation in the presence of an electron density variation of approximately R−4. In addition, the H30α and H26α line masers arise from different parts in the wind. This difference is also expected from maser theory. The wind component of both masers exhibits line-of-sight velocities that closely follow a Keplerian law. This result provides strong evidence that the disk wind extracts significant angular momentum, thereby facilitating mass accretion in the young star. [ABSTRACT FROM AUTHOR]