Additional recovery in x-irradiated Oedogonium cardiacum can be suppressed by cycloheximide.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to A Laszlo.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Mycobacterial isolates from blood and other extrapulmonary sites of six patients with AIDS were investigated because the isolates grew only in liquid media and failed to grow on solid culture media even on subculturing. Our investigations indicated that these mycobacteria possess common, but unusual, characteristics and probably belong to an unrecognized species recently reported as "Mycobacterium genavense."
The specificity of Mycobacterium tuberculosis anti-PGL-Tb1 antiserum prepared in rabbits was evaluated by an enzyme-linked immunosorbent assay. It was found that the antiserum immunoreacted with its homologous antigen but not with purified phenolic glycolipids from M. bovis BCG (mycoside B), M. kansasii (mycoside A), M. leprae (PGL-I) or M. marinum (mycoside G). The analysis of chloroform/methanol extracts from 15 strains of M. tuberculosis showed that all formed the antigen except the type strain (strain H37Rv). Chloroform/methanol extracts of M. bovis BCG, M. xenopi, M. flavescens and M. fallax cross-reacted with the immune serum. However, chloroform/methanol extracts of representative strains of 18 other mycobacterial species did not react, therefore indicating that these did not contain the antigen.
The effect of the inhibition of protein synthesis on the development of thermotolerance in Chinese hamster fibroblasts following a brief heat shock or exposure to sodium arsenite has been examined. Under conditions that inhibit protein synthesis by 95 per cent, significant amounts of thermotolerance develop after a brief exposure to 45 degrees C or continuous exposure to 41 degrees C, without the significant accumulation of heat shock proteins. However, no thermotolerance development in cells treated with sodium arsenite was observed if protein synthesis was inhibited. Heated cells which developed thermotolerance in the absence of protein synthesis are subject to the thermal sensitizing action of subsequent exposure to amino acid analogues, while cells which developed thermotolerance with unimpeded protein synthesis are refractory. These results suggest that heat can simultaneously induce two states of thermotolerance, only one of which is dependent on protein synthesis. These two states can be distinguished operationally with respect to their response to amino acid analogue exposure.
OBJECTIVE: To estimate the prevalence of resistance of Mycobacterium tuberculosis to first-line antituberculosis drugs in Canada. METHODS: M. tuberculosis isolates from one third of all culture-positive tuberculosis (TB) cases diagnosed between February 1, 1993 to January 31, 1994 in Canada were collected prospectively. Proportion of drug-resistant isolates and the factors related to drug resistance were measured. RESULTS: Of 458 study cases, 40 (8.7%) had resistance to at least one first-line antituberculosis drug, of which 5.9% had mono-resistance, 0.7% had multidrug-resistance(MDR-TB)--i.e., resistance to at least isoniazid and rifampin--and 2.2% had other patterns. The overall prevalence of resistance among the foreign-born cases was 10.6% with the highest level among those who resided in Canada for less than four years (15.5%). CONCLUSIONS: Canada has a relatively low prevalence of antituberculosis drug resistance and a very low prevalence of MDR-TB. Some new immigrants to Canada may be at higher risk for drug resistance and their initial treatment needs to be tailored accordingly.
Explore the source record for details and available documents.