Effect on mortality of inhalation injury

A retrospective analysis of 1,018 consecutive admissions with cutaneous burn injury over 32 months was carried out. Mortality probabilities as related to age, per cent TBSA burn, and presence of inhalation injury are presented. Incidence of and mortality from inhalation injury both rose with increasing burn area. The incidence of inhalation injury also rose with advancing age; mortality was lowest in the 5- to 14-year old age group and highest in those more than 59 years of age.     

A comparison of parenteral loxapine and haloperidol in hostile and aggressive acutely schizophrenic patients

In a parallel groups, double-blind study, 54 acutely psychotic schizophrenics were given loxapine or haloperidol parenterally for 24 to 72 hours, then orally for a total study period of up to 10 days. Dosage ratios of loxapine to haloperidol ranged from a minimum of 2.7:1 to a maximum of 4.4:1. Both groups showed significant and rapid improvement from baseline. Forty-eight percent of the loxapine patients and 33% of the haloperidol patients achieved and maintained a global severity of illness rating of mild or better. By the end of the study, 84% of the loxapine patients and 63% of the haloperidol patients had achieved an improvement rating of moderate or marked. This difference approached significance (p less than .10). The most frequently reported adverse experiences were dystonic reactions and akathisia. The number and severity of adverse experiences did not differ significantly between drug groups. Intramuscular loxapine was at least as effective as haloperidol in the initial management of hostile and aggressive schizophrenic patients. The maintenance of therapeutic response after conversion to oral concentrate was comparable with the two drugs.     

1-Methyl-4-(2'-methylphenyl)-1,2,3,6-tetrahydropyridine (2'-CH3-MPTP) is a more potent dopaminergic neurotoxin than MPTP in mice

The administration to mice of 1-methyl-4-(2'-methylphenyl)-1,2,3, 6-tetrahydropyridine (2'-CH3-MPTP), a substituted analog of the dopaminergic neurotoxin MPTP caused even more dopaminergic toxicity than MPTP itself. Under conditions in which MPTP was relatively ineffective (i.e. two injections per day of 0.113 mmol/kg at an interval of 6 h for one or two days), 2'-CH3-MPTP caused a very large decrement in the neostriatal content of dopamine and its metabolites and a corresponding decrement in the capacity of a neostriatal synaptosomal preparation to take up [3H]dopamine. Moreover, 2'-CH3-MPTP administration (as few as four injections) caused a virtually complete loss of nerve cells in the zona compacta of the substantia nigra. This compound, like MPTP, may prove to be a valuable research tool.     

Central and peripheral changes in catecholamine-synthesizing enzyme activities after systemic administration of the neurotoxin DSP-4

In brain regions containing noradrenergic (NA) cell bodies or terminals, DSP-4 induces changes in the activity of catecholamine-synthesizing enzymes which suggest that central NA neurons are lesioned by this neurotoxin. In contrast, the lack of change in the same enzymatic activities in an area containing mostly adrenergic (A) neurons (C2 region), favors the hypothesis of a resistance of the A neurons to DSP-4. Furthermore, the enzymatic changes observed in peripheral organs suggest a peripheral activation of the NA cell bodies in response to lesioning of the sympathetic terminals by DSP-4.     

In vitro metabolism and toxicity assessment of toxin T-514 (Peroxisomicine A1) of Karwinskia humboldtiana in microsomes and primary cultured hepatocytes.

T-514 (Peroxisomicine A(1)) from Karwinskia humboldtiana is a dimeric hydroxyanthracenone with a highly selective cytotoxic effect on tumor cells. We evaluated the metabolism of this compound in two in vitro systems (liver microsomes and hepatocytes) and assessed the cytotoxicity of its metabolites on normal and tumor cells. Microsomes (12.5, 125 and 250 microg of protein/ml) and hepatocytes (1 x 10(6) cells/ml) were incubated with the toxin (25 microM) for 0.5, 1, 3, 6, 9, 12 and 24 h and the samples were examined using chromatographic analysis and UV spectra. Two metabolites (M1 and M2) were detected in the rat microsomes and one (M1) in the monkey microsomes. The retention times and UV spectra of the peaks were very similar to those of the toxin T-514. M1 was isolated and identified as a mixture of two isomers. The cytotoxicity of the metabolites was evaluated in Chang liver and Hep G2 cells but they did not show the selective cytotoxic effect on tumor cells seen in the original compound.     

Is there a role for reconstructive techniques to prevent periodontal defects after third molar surgery?

PURPOSE: Among patients at high risk for second molar (M2) periodontal defects after third molar (M3) removal, does active treatment at the time of extraction, when compared with no treatment, alter the risk of postextraction M2 periodontal defects? MATERIALS AND METHODS: We used a prospective cohort study design and a sample composed of subjects at high risk for developing M2 periodontal defects after M3 extraction, that is, age > or = 26 years, pre-existing periodontal defects (attachment level [AL] > or = 3 mm), and mesioangular or horizontal M3 impaction. The predictor variable was treatment status of the M3 extraction site. The M3 extraction sites were reconstructed with demineralized bone powder (DBP), bioresorbable guided tissue regeneration (GTR) therapy, or no treatment. The outcome variable was ALs measured at the M2 distobuccal line angle preoperatively and 26 weeks after extraction. Appropriate univariate, bivariate, and multivariate statistics were computed, and statistical significance was set at a value P < .05. RESULTS: The cohort was composed of 12 subjects contributing 18 high-risk M3s. Twenty-six weeks after M3 removal, the ALs for GTR-treated (3.0 +/- 1.2 mm), DBP-treated (1.4 +/- 0.5 mm), and control (3.8 +/- 0.9) M3 sites were statistically significantly different ( P = .002). Tukey post-hoc comparisons revealed a statistically significant difference between control and DBP ALs ( P = .001) and GTR-treated and DBP-treated ALs ( P = .037). There was no statistically significant difference in ALs between control and GTR-treated M3s ( P = .35). CONCLUSIONS: The results of this study suggest that subjects at high risk for developing M2 periodontal defects after M3 removal may benefit from the use of DBP placed at the time of M3 extraction to enhance periodontal healing.