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B Terleckyj

Publications and source records attributed to B Terleckyj.

14 recordsLinked to original sources
PubMed1995

Antiseptics and disinfectants. Current issues.

The authors address current issues regarding use of antiseptics and disinfectants with particular emphasis on the problems associated with claims made by manufacturers of various chemical agents. Other issues include the efficacy and limitations of commercial products, selecting the most appropriate formulation for proper disinfection, especially with instruments that come in contact with the patient, and preventing or minimizing iatrogenic infections in clinical practices. The authors stress that low-level and some intermediate-level disinfectants are unreliable because of their narrow safety margin and that chemical agents with a high level of activity should be used by all practitioners because of multi-drug resistant microorganisms and acquired immune deficiency syndrome (AIDS).

Acquired Immunodeficiency Syndrome↗
PubMed1993

Efficacy of disinfectants against fungi isolated from skin and nail infections.

Commercial disinfectants classified as fungicides may not be effective against commonly encountered fungi within reasonable periods. Cell suspensions of clinical fungal isolates were exposed to use-dilutions of various disinfectants. Quaternary ammonium compounds, iodophors, and phenolics were not fungicidal against all test fungi within 60 min of exposure. Trichophyton mentagrophytes, Epidermophyton floccosum, and Aspergillus fumigatus were among the more resistant fungi. Disinfectants that possess low-level activity should not be used for disinfection of medical instruments that come in contact with the patient. The only reliable and safe measure is to use high-level disinfectants such as the glutaraldehydes, which are fungicidal in 15 to 30 min.

Disinfectants↗
PubMed1987

Quantitative neutralization assay of fungicidal activity of disinfectants.

A quantitative assay using a neutralization medium was developed to evaluate fungicidal activity of disinfectants. Concentrated Dey-Engley neutralizing broth was used in this study and was demonstrated to inactivate various chemical agents within 5 min when disinfectant concentrations were reduced to specific levels. Addition of this Dey-Engley broth to test tubes containing fungal cells and disinfectants permitted control of the various interactions times. Subsequent concentration of the disinfectant-treated cells to a 1-ml final volume also permitted examination of a larger population for the presence of resistant cells. After timed exposures of 15, 30, and 60 min, only three of seven disinfectant solutions were found to be lethal for quantitative populations of 11 fungi tested. The recommended use dilution formulations of a quaternary ammonium product and an iodophor product were the least effective agents. Various fungi, including Trichophyton mentagrophytes, Epidermophyton floccosum, and Aspergillus niger, survived 30- to 60-min interactions with these disinfectant solutions. The most resistant organism encountered was Aspergillus fumigatus, which survived 60 and even 90 min of exposure to most disinfectants. Only use dilutions of a chlorine dioxide formulation, a glutaraldehyde formulation, and an ethyl alcohol product were effective against this species and all of the other fungi after a 15-min interaction.

Candida albicans↗
PubMed1975

Growth of several cariogenic strains of oral streptococci in a chemically defined medium.

A chemically defined medium in which Streptococcus mutans strains AHT, BHT, GS-5, JC-2, Ingbritt, At6T, At9T, 6715, and OMZ-176 and Streptococcus salivarius strain HHT grew rapidly to high turbidities was formulated. Maximal turbidities of each strain were observed after 8 to 12 h of aerobic growth. The subsequent transfer of exponentially growing cells into fresh medium resulted in growth at the same rate without lag. Growth of these strains occurred with rates at least one-half of those observed in an organic medium, such as Todd-Hewitt broth. S. mutans strains FA-1 and OMZ-61 grew at relatively slow rates in the defined medium, but more rapidly growth to higher turbidities of both strains was obtained when sodium bicarbonate was added to the medium. Streptococcus sanguis strain OMZ-9 and another group H streptococcus (strain 72 times 46) grew rapidly in the defined medium after the addition of sodium carbonate. The presence of carbonate or bicarbonate yielded higher turbidities of all the other strains, and the growth rates of several of the strains tested were also increased.

Bacteriological Techniques↗
PubMed1975

Amino acid requirements of Streptococcus mutans and other oral streptococci.

The amino acid requirements of Streptococcus mutans strains AHT, OMZ-61, FA-1, BHT, GS-5, JC-2, Ingbritt, At6T, OMZ-176, 6715, Streptococcus salivarius HHT, Streptococcus sanguis OMZ-9, and strain 72x46 were determined in a chemically defined medium. When grown anaerobically in the presence of sodium carbonate (or bicarbonate for a few strains), few amino acids were required. All strains tested required cystine (or cystine) as a nutrient. Three strains (S. mutans OMZ-176, FA-1, and BHT) required glutamate (and/or glutamine). A third amino acid (lysine for S. mutans FA-1 and histidine for S. mutans OMZ-176) was required by two of the three strains which required glutamate. The amino acids mentioned above were required for all conditions of incubation (and inoculum) tested. The requirements for several other amino acids were conditional, that is, dependent on the incubation conditions and inoculum used. For example, when carbonate was not added, glutamate was required by S. mutans GS-5. Aerobic incubations, with carbonate or bicarbonate added, resluted in requirements for glutamate and leucine by several strains. With these incubation conditions, one strain required isoleucine (S. mutans FA-1), another valine (S. mutans AHT), and a third tyrosine (72x46). Aerobic incubations in the absence of carbonate or bicarbonate further increased the number of amino acids required by several strains. Furthermore, when stationary-phase cultures replaced exponentially growing cultures as an inoculum, several strains required additional amino acids, presumably for the initiation of growth.

Amino Acids↗
PubMed1975

Analysis of growth rate in sucrose-supplemented cultures of Streptococcus mutans.

In the presence of sucrose, Streptococcus mutans grows in large glucan-containing aggregates. Because of reports of linear rather than exponential growth of sucrose-grown cultures, the kinetics of growth of sucrose-grown cultures of S. mutans strain OMZ-176 were compared with those of glucose-grown cultures. Culture turbidity measurements indicated that growth of sucrose cultures was slower, did not follow exponential kinetics, and slowed and stopped at lower absorbance values than did glucose-grown cultures. However, measurements of the rates of accumulation of deoxyribonucleic acid (DNA), ribonucleic acid (RNA), and protein using fully equilibrated radioactively labeled precursors of each of these macromolecular species in sucrose and glucose-grown cultures showed that: (i) for glucose cultures the synthesis of each of the three informational molecules occurred at the same exponential rate, which was identical to the rate of turbidity increase; (ii) for sucrose cultures each macromolecular species was synthesized at the same exponential rate and these rates were identical to the rate of increase of turbidity of the glucose-grown culture for periods of up to 7 h. Furthermore, the ratios of DNA to RNA, RNA to protein, and protein to DNA for the sucrose cultures were identical to those for the glucose cultures for up to 10 doublings. From these data it was concluded that in the presence of sucrose S. mutans grows in a balanced fashion at the same exponential rate as it does in glucose. The deviation from an exponential growth model of the absorbance in sucrose cultures was attributed to an optical artifact due to the formation of large glucan-containing aggregates of cells. The addition of dextranase to sucrose cultures resulted in cultures which increased in turbidity at the same exponential rate as glucose-grown cultures, without affecting the rate or extent of macromolecular synthesis.

Carbon Radioisotopes↗