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O Dorneanu

Publications and source records attributed to O Dorneanu.

3 recordsLinked to original sources
PubMedDate not supplied

Gas chromatographic detection of Mycobacterium tuberculosis complex in pure cultures from respiratory specimens.

It is important to identify mycobacteria to the species level in order to establish their clinical significance and to take the appropriate therapeutical decision. Biochemical tests on primary cultures take time (3-6 weeks) until the report of results; that's why more rapid techniques are needed. We have used gas chromatography with flame-ionisation detection (GC-FID) as an alternative identification method for 53 mycobacterial strains isolated from respiratory specimens. We have extracted fatty acids from whole mycobacterial cells, then derivatized them into methylesters, detectable by GC-FID. All the strains were identified as M. tuberculosis complex (MTC), using the Microbial Identification System (MIS) software. The specificity of the identification by GC-FID of MTC is 100%. In conclusion, pulmonary mycobacteriosis are dominated by MTC; GC-FID is a rapid and accurate method for the identification of MTC.

Chromatography, Gas↗
PubMedDate not supplied

[Assessment of Tc-99m MIBI uptake mechanism in Mycobacterium tuberculosis and normal cells (fibroblasts and myocytes) cultures].

One of the factors which can explain the scintigraphic Tc-99m MIBI positives images in pulmonary tuberculosis could be the Mycobacterium tuberculosis radiotracer uptake; this can be investigated in vitro, on cell culture, in comparison with normal cell types known to have high (myocites) or low (fibroblasts) uptake. Mycobacterium tuberculosis cultures were realised on Löwenstein Jensen medium, by standard methodology. Myocites and fibroblasts cultures were realized from neonatal rat hearts. Monolayer cells culture were incubated with a same 1.85 kBq/?l Tc-99m MIBI concentration, at 37 degrees C for 15, 60 and 90 minutes. The kinetic was stopped by rapidly washing the cells, with a 4 degrees C physiological saline solution and than scrapped cells were counted for the uptaken radioactivity. The results show that radiotracer cellular uptake (reported at the protein concentration) in myocites was maximum at 60 minutes. Cellular uptake in fibroblasts was very low at all the intervals. In Mycobacterium tuberculosis a peak was observed after 15 minutes, the uptake being similar to that of 60 minutes incubated myocites, considered 100%. After 90 minutes the Mycobacterium tuberculosis uptake was smaller than the 15 minutes value (65.82%). In conclusion, Mycobacterium tuberculosis in vitro uptake results could explain the more positives scintigraphic images in BK positive patients obtain at 15 minutes, in comparison with the delayed images.

Animals↗