Isolation and characterization of ribosomes from Bacillus subtilis spores.

Bishop, Helen L. (Syracuse University, Syracuse, N.Y.), and Roy H. Doi. Isolation and characterization of ribosomes from Bacillus subtilis spores. J. Bacteriol. 91:695-701. 1966.-The isolation of ribosomes from Bacillus subtilis spores was accomplished by freezing the spores in liquid nitrogen and grinding the spore pellet with an equal weight of levigated alumina. The ribosomes, which were adsorbed to the alumina, were freed by the addition of vegetative-cell ribosomes or bulk ribonucleic acid (RNA) to the crude alumina-ground extract. The spore ribosomes had sedimentation properties and RNA and protein compositions similar to those of vegetative-cell ribosomes. The difficulty encountered in obtaining spore ribosomes by ordinary extraction methods may be the result of nuclease and protease activities which were demonstrated in spore extracts.

Peptide synthesis by extracts from Bacillus subtilis spores.

Cell-free peptide synthesis by extracts from vegetative cells and spores of Bacillus subtilis was analyzed and compared. The initial rate of phenylalanine incorporation in a polyuridylate-directed system was found to be in a similar range for the two extracts. However, spore extracts frequently incorporated less total phenylalanine as did the vegetative cell system. Optimal conditions for amino acid incorporation by spore extracts were found to be similar to those of vegetative cell extracts. Polyphenylalanine synthesis was stimulated by preincubation of both extracts prior to the addition of polyuridylic acid (poly U) and labeled phenylalanine. Both systems showed a dependence on an energy-generating system and were inhibited by chloramphenicol and puromycin. Ribonuclease, but not deoxyribonuclease, inhibited the reaction significantly. The presence of methionine transfer ribonucleic acid (tRNA(F)) and methionyl-tRNA(F) transformylase was demonstrated in spore extracts. An analysis of several aminoacyl-tRNAs in spores revealed that the relative amounts of these tRNAs were similar to those found in vegetative cells. Only lysine tRNA was found to be present in relatively greater amounts in spores. These results indicate that dormant spores of B. subtilis contain the machinery for the translation of genetic information.

Role of two-dimensional echocardiography in the evaluation of patients with ventricular septal rupture postmyocardial infarction.

In 18 consecutive patients with a new murmur following acute myocardial infarction (AMI), examination by two-dimensional echocardiography (2DE) correctly excluded ventricular septal defects (VSD) in eight patients and enabled direct visualization of the VSD in 10 patients. In three patients, 2DE was the first technique to establish the diagnosis. In all patients with VSD, 2DE diagnosis was confirmed by catheterization, surgery, and/or postmortem examination. In six patients with VSD, 2DE contrast studies were performed and were positive. 2DE enabled localization of the VSD in all patients (five inferior, five anterior). To evaluate left ventricular (LV) function, a 2DE wall motion index (WMI) was calculated using an 11 segment model of the LV. While there was no difference (p greater than 0.2) in AMI-VSD survivors versus nonsurvivors in age, kinase, and AVO2 difference, there was no overlap in WMI (p = 0.004) of survivors (0.80 +/- 0.36) versus nonsurvivors (1.66 +/- 0.19). Thus 2DE allows accurate detection and localization of postmyocardial infarction VSD and enables determination of prognosis of these patients.

Acute and long-term hemodynamic effects of oral pirbuterol in patients with chronic severe congestive heart failure: randomized double-blind trial.

In 20 patients with severe congestive heart failure (CHF), we studied the effects of the beta-adrenergic agonist pirbuterol compared to placebo in both an acute double-blind randomized trial and after long-term treatment. Acutely, pirbuterol patients (n = 10) demonstrated a significant rise in cardiac index (2.2 +/- 0.14 to 3.2 +/- 0.32 L/min/m2), stroke index (26 +/- 2.6 to 35 +/- 2.9 ml/beat/m2), stroke work index (22 +/- 2.4 to 30 +/- 2.7 gm X m/m2), and ejection fraction (22 +/- 4 to 30 +/- 5%). These hemodynamic variables did not significantly change in placebo patients (n = 10). After 3 weeks of pirbuterol therapy, 14 patients (70%) were symptomatically improved and were continued on the drug for another 3 weeks; 13 of 14 patients who were symptomatically improved underwent restudy. Compared to pretreatment baseline, there was continued improvement in cardiac index (2.5 +/- 0.16 to 3.2 +/- 0.24 L/min/m2), stroke index (30 +/- 2.5 to 38 +/- 2.9 ml/beat/m2), stroke work index (26 +/- 2.3 to 35 +/- 3.1 gm X m/m2), and ejection fraction (24 +/- 1 to 28 +/- 4%). Patients more frequently improved were those with nonischemic cardiomyopathy and those with higher initial ejection fractions. These results demonstrate the acute beneficial effects of oral pirbuterol versus placebo in a double-blind randomized trial. Improvement was maintained during long-term therapy in the majority of CHF patients.