Biomedical subjects

A Hutchison

Publications and source records attributed to A Hutchison.

30 records · Page 2Linked to original sources

PubMed1988

CGS 19755 is a potent and competitive antagonist at NMDA-type receptors.

The N-Methyl-D-aspartate (NMDA)-type receptor blocking properties of CGS 19755, a novel, rigid analog of 2-amino-5-phosphonopentanoate, were demonstrated in vitro by the ability of the compound to block NMDA-evoked [3H]acetylcholine release (pA2 = 5.93). CGS 19755 (0.045 and 0.224 mmol/kg i.p.) was shown to be active in vivo as well by its ability to block harmaline-induced increases in cerebellar cGMP. Finally, CGS 19755 blocked sound-induced seizures in DBA/2 mice completely at doses of 1.0 nmol i.c.v. or 0.1 mmol/kg i.p. Taken together, these data indicate that CGS 19755 is a potent and competitive NMDA antagonist in vitro which is also active in vivo.

Acetylcholine↗

PubMed1988

Sequence analysis of ARS elements in fission yeast.

Chromosomal DNA of Schizosaccharomyces pombe contains sequences with properties analogous to ARS elements of Saccharomyces cerevisiae. Following Sau3A fragmentation of the S. pombe genome we have recovered a number of such fragments in an M13-based shuttle vector, suitable for subsequent sequence analysis. The complete nucleotide sequence has been obtained for eight ARS+ inserts derived from the Sau3A cloning and for the ARS present in pFL20 isolated previously by Losson and Lacroute (Cell, 32, 371-377, 1983). The Sau3A clones are single fragments between 0.8 and 1.8 kb. No ARS+ clones smaller than this were recovered even though the average size Sau3A fragment in S. pombe is approximately 200-300 bp. The sequence analysis revealed that all clones are AT-rich (69-75% A + T residues), and all contain a particularly AT-rich 11 bp core element represented by the consensus sequence 5' (A/T)PuTT-TATTTA(A/T) 3'. Deletion mapping indicates that the consensus in all cases is in the vicinity of a functional ARS domain. However precise excision of the consensus by in vitro mutagenesis has little effect on ARS activity as judged by the transformation assay. We argue that the association of the consensus with the ARS domain occurs too reproducibly to be explained by chance alone. We suggest that although it may not be essential for the extrachromosomal maintenance of plasmids in S. pombe, the consensus does have a function in situ in the chromosome and thus is always present as a cryptic sequence in the isolated ARS element.

Base Sequence↗

PubMed1985

Absorption of 1.5% glycine after percutaneous ultrasonic lithotripsy for renal stone disease.

An elderly normotensive man underwent percutaneous ultrasonic lithotripsy for renal stone disease, the procedure lasting three hours and the fragments being washed out with 20 l 1.5% glycine. After two hours the inflation pressure had risen to 25 cm H2O and his blood pressure to 150 mm Hg. Inflation pressure continued to rise until drainage tubes were inserted into the retroperitoneal space, releasing a large volume of fluid, some of which appeared to be from the peritoneal cavity. Shortly after transfer to the recovery area the patient showed signs of the transurethral resection syndrome, with hyponatraemia, hyperkalaemia, and hypertension. He was treated appropriately and survived. Low infusion pressures should be used for irrigation during lithotripsy and 0.9% saline instead of 1.5% glycine. In patients given a general anaesthetic any rise in inflation pressure suggests extravasation of fluid and warrants emergency estimation of the plasma sodium concentration.

Absorption↗

PubMed1983

Serial sonographic monitoring of intracranial hemorrhage (ICH) and its sequelae in the preterm neonate.

This study documents changes in ventricular size and brain parenchyma that occurred in 41 preterm neonates that had intracranial hemorrhage, out of 136 preterm neonates that were serially examined. Serial real-time sonographic examinations disclosed a close relationship between the severity of ICH and the development of progressive ventricular dilatation. Eighty percent of preterm neonates with minor degrees of ICH [localized subependymal hemorrhage (SEH) or SEH with small intraventricular hemorrhage (SEH/IVH)] did not develop significant ventricular dilatation, whereas all of the neonates with IVH and/or intraparenchymal hemorrhage (IPH) developed moderate or severe ventricular dilatation. Spontaneous resolution of moderate and/or severe ventricular dilatation did occur by the end of the third week of life in approximately one third of neonates with ICH. The therapeutic implications of the findings are discussed.

Birth Weight↗

PubMed1982

Betamethasone, albuterol, and threatened premature delivery: benefits and risks. Study of 469 pregnancies.

This report details the outcome of pregnancy in 469 patients admitted before 34 weeks' gestation with premature labor with intact membranes (253 patients) or premature rupture of the membranes (PROM) but no labor (216 patients). Betamethasone significantly reduced the incidence of severe respiratory distress syndrome (RDS) both in patients with intact membranes and in those with PROM. PROM had a significant beneficial effect on the incidence of RDS in both groups of patients, those who had received betamethasone and those who had not. Fetal sex did not significantly influence the respiratory response to either PROM or betamethasone administration, except that betamethasone treated female fetuses showed a significantly better response to PROM than similarly treated males. Except in patients with PROM associated with a cervical suture, betamethasone administration did not increase the risk of perinatal or maternal infection.

Albuterol↗

PubMed1975