A retrospective, exploratory, secondary analysis of the association between antipsychotic use and mortality in elderly patients with delirium.

BACKGROUND: Delirium, an acute altered level of cognition, is a frequent complication of medical illness in the elderly. Antipsychotic medications (APs) are often used to treat agitation and psychosis in delirium. The goal of this study is to compare mortality in delirious elderly medical inpatients treated with APs with those who did not receive APs. METHOD: 326 elderly hospitalized patients were identified with delirium at an acute care community hospital. A nested case-control analysis was conducted on this cohort. Cases consisted of all patients who died in hospital within eight weeks of admission. Each case was matched for age and severity of illness to patients (controls) alive on the same day post-admission. Conditional logistic regression was used to assess the impact of exposure to AP on mortality. Covariates used for adjustment were the Charlson comorbidity score and the acute physiology score. Odds ratio (OR) and 95% confidence intervals were calculated from the regression coefficients. RESULTS: 111 patients received an AP. A total of 62 patients died, 16 of whom were exposed to an AP. The OR of association between AP use and death was 1.53 (95% C.I, 0.83-2.80) in univariate and 1.61 (95% C.I, 0.88-2.96) in multivariate analysis. CONCLUSION: In elderly medical inpatients with delirium, administration of APs was not associated with a statistically significant increased risk of mortality. Larger studies are needed to clarify the safety of AP medication in elderly patients with delirium.

Reversal of scopolamine-induced deficits in navigational memory performance by the seed oil of Celastrus paniculatus.

Celastrus paniculatus (CP), a medicinal plant from India has been reputed to be useful as a pharmaceutical aid for learning and memory. We investigated the effects of the seed oil of CP on the 6 day performance of young adult rats in a navigational memory task-the Morris water maze. Chronic oral (gavage) daily treatment with CP. (50, 200, or 400 mg/kg) for 14 days completely reversed the scopolamine (0.5 mg/kg)-induced task performance deficit. On the other hand, acute treatment (single injection prior to scopolamine treatment) with CP (200 mg/kg) did not significantly reverse the scopolamine-induced impairment in maze performance. Alone, CP produced a slight, but significant improvement in maze performance on the first day of testing. Acute treatment or chronic 14 day treatment with CP resulted in no significant alteration in normal locomotor activity in an open field. Moreover, CP did not alter the scopolamine-induced increases in locomotor activity. Chronic treatment with CP did not alter brain acetylcholinesterase levels and no signs of cholinergic overstimulation were ever noted during or after treatment. Thus, the seed oil of CP, when administered chronically, selectively reversed the impairment in spatial memory produced by acute central muscarinic receptor blockade, supporting the possibility that one or more constituents of the oil may offer cognitive enhancing properties. The neural mechanism underlying the reversal of scopolamine's mnemonic effects by CP is not yet known, but it is not related to an anticholinesterase-like action.

Cognitive impairment in spontaneously hypertensive rats: role of central nicotinic receptors. I.

Both human essential hypertension and genetically induced hypertension in rats have been associated with a range of impairments of cognitive ability. The spontaneous hypertensive rat (SHR) previously has been shown to exhibit a decrease in the expression of brain nicotinic acetylcholine receptors, a factor that could play a role in the impaired ability of this strain in the performance of learning and memory-related tasks. The purpose of this study was to help determine whether task impairment by SHR was related to the reduced expression of central nicotinic acetylcholine receptors. Twelve-week-old SHR were tested in two phases of a water maze (spatial memory) task, and their performance was compared with that of two age-matched normotensive strains, Wistar Kyoto (WKY) and Wistar rats. During Phase 1, SHR exhibited significantly increased latencies to locate a hidden platform as compared with either WKY or Wistar rats. During Phase 2 (subsequent series of trials after a 4-day inter-phase period), where rats were required to find a new platform location, SHR again exhibited significantly impaired performance compared to the normotensive strains. In a single trial passive avoidance paradigm, SHR again displayed significantly reduced avoidance behavior as compared with both WKY and Wistar rats. In consecutive coronal sections, the density of [3H]cytisine binding sites was decreased in SHR by up to 25% in about half of the brain regions examined, with the deficits particularly apparent in cephalic regions. The binding of [125I]alpha-bungarotoxin to brain sections also was decreased in SHR; however, only certain brain areas exhibited significant interstrain differences. These alterations in the expression of putative nicotinic receptor subtypes in SHR were not due to changes in the density of cholinergic neurons since there were no interstrain differences in the binding densities for [3H]vesamicol, which labels the vesicular acetylcholine transporter. Moreover, the magnitude of nicotine-stimulated rubidium efflux from cortical and striatal synaptosomes in vitro was significantly reduced in samples derived from SHR as compared with those from normotensive rats. These results are consistent with the possibility that a reduction in the expression of cortical nicotinic receptors in SHR plays a role in this strain's impaired performance of both spatial and non-spatial learning and memory-related tasks.

Cell saver efficacy for routine coronary artery bypass surgery.

A retrospective study was conducted to determine the effect of intraoperative Haemonetics Cell Saver (HCS) usage on postoperative homologous blood product requirements in CABG patients. From 1 January to 31 December 1993, 516 patients without renal disease or postoperative surgical or gastrointestinal haemorrhage had elective, first-time CABG surgery. The HCS was utilized in 435 of these patients (Group CS) and in 81 patients the HCS was excluded (Group NCS). Preoperative patient variables were similar in the group. We evaluated the HCS effect on blood product transfusion by comparing -x units of red blood cells (RBC), fresh frozen plasma (FFP) and platelets (PLTS) transfused per patient between groups CS and NCS. There were no differences in the -x units of RBC (1.9 +/- 2.7 CS vs. 1.8 +/- 1.5 NCS) or in the RBC transfusion rate (48% CS vs 50% NCS). There were also no significant differences between the groups in -x units of FFP (0.9 +/- 0.8 CS vs 0.4 +/- 0.9 NCS) or PLTS (0.7 +/- 3.1 CS vs 0.4 +/- 2.5 NCS), or in the percentage of patients receiving these products (12% CS vs 8% NCS). These data provide no evidence that the use of the HCS decreases the amount of homologous blood bank products required postoperatively in patients having routine first-time CABG surgery. The current era of aggressive blood conservation may have limited the role of the HCS in routine CABG surgery.

1-(1-chlorovinyl)-2,7-dimethoxynaphthalene.

C14H13ClO2, Mr = 248.71, monoclinic, P21/n, a = 11.291 (1), b = 7.343 (1), c = 15.223 (2) A, beta = 90.899 (8) degrees, V = 1262.0 (5) A3, Z = 4, Dx = 1.309 g cm-3, lambda(CU K alpha) = 1.54184 A, mu = 26.0 cm-1, F(000) = 520, T = 299 K, R = 0.041 for 2405 observations (of 2516 unique data). The average deviation from planarity is 0.019 (2) A with a maximum of 0.035 (1) A for the fused rings. The dihedral angle between the naphthalene system and the chlorovinyl group is 101.93 (4) degrees. The methoxy group ortho to the chlorovinyl adopts a conformation with the methyl group anti to the neighboring alpha carbon of the ring, with a C-C-O-C torsion angle of -175.6 (2) degrees. The other methoxy group has the methyl syn to the neighboring alpha carbon, with a C-C-O-C torsion angle of 1.9 (3) degrees.

A comparison of the IgG isotype expression in the so-called thymus-independent immune responses to alpha(1----3) and alpha(1----6) dextran.

This paper presents data on the IgG antibody response against two "thymus-independent" dextran (Dex) antigens from Leuconostoc mesenteroides, alpha(1----3) Dex B 1355S and alpha(1----6) Dex B 512F in BALB/c and C57BL/6 mice, which are considered to be responders or low responders to the respective antigen. The data point toward three common rules governing the two anti-Dex responses despite immunogenetic and antigenic disparities: (1) age dependency of the IgG isotype regulation of the response; (2) down-regulation of IgG isotype expression by T cells; and (3) individually determined preposition for IgG isotype formation in a given animal.

Does dimeric melittin occur in aqueous solutions?

Melittin, a peptide from bee venom, is known to undergo a monomer / tetramer conversion in aqueous solutions. We have studied the possible participation of dimers in the association equilibrium of melittin by sedimentation equilibrium experiments in the analytical ultracentrifuge and subsequent mathematical analysis of the concentration distributions obtained. It was found that the dimeric state is not significantly populated, the contribution of dimer to the total peptide weight probably being below 0.5%.

An ultracentrifuge study on the self-association of glucose dehydrogenase from Bacillus megaterium.

The self-association of glucose dehydrogenase (beta-D-glucose:NAD(P) 1-oxidoreductase, EC 1.1.1.47) from Bacillus megaterium was studied by analytical ultracentrifugation. The pH and composition of the buffer used were such that, owing to a reversible partial dissociation of the tetrameric enzyme, enzyme activity was reduced. It was found that under these conditions the protein exists in a monomer/dimer/tetramer association equilibrium.

The nature of the stable noncovalent dimers of band 3 protein from erythrocyte membranes in solutions of Triton X-100.

Stable noncovalent dimers of band 3 protein from human erythrocyte membranes, in which state the protein is thought to exist after solubilization by the nonionic detergent Triton X-100, do not occur when purified batches of the detergent are used. Instead, the protein is in a monomer/dimer/tetramer association equilibrium. The stable dimers do appear, however, when the detergent has been 'aged'. They thus seem to be artifacts.

Band 3 protein-cholesterol interactions in erythrocyte membranes. Possible role in anion transport and dependency on membrane phospholipid.

Band 3 protein of the human erythrocyte membrane, the anion transport protein, possesses a high affinity steroid binding site. In mixed phospholipid-cholesterol monolayers, the state of occupancy of this site is positively correlated with their cholesterol and sphingomyelin content and negatively with their glycerophospholipid content. We suggest that, in the erythrocyte membrane, the binding site is an inhibitory site of anion transport and that the modulation of its state of occupancy by the membrane lipid is responsible for the negative correlation of anion transport with the membrane's content of cholesterol and sphingomyelin and the positive correlation with the phosphatidylcholine content.