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Biomedical subjects

R M Boucher

Publications and source records attributed to R M Boucher.

14 recordsLinked to original sources
PubMed1991

The otolaryngic manifestations of multiple sclerosis.

Multiple sclerosis is a disease characterized pathologically by the disseminated demyelination of central nervous system white matter and clinically by episodes of focal neurologic deficit that occur in a relapsing and remitting course usually over many years. In most cases progressively fixed deficits occur with resultant moderate to severe disability. Symptoms and signs of multiple sclerosis are reviewed, with emphasis placed on the protean manifestations and natural history of the disease.

Clinical Protocols↗
PubMed1990

The diagnosis of Thornwaldt's cyst.

Thornwaldt's cyst is an uncommon nasopharyngeal lesion which develops from the remnant of the primitive notochord. A case report of a patient with a Thornwaldt's cyst and cervical adenitis is presented. Though computed tomography of the head and neck was unremarkable, magnetic resonance imaging of the nasopharynx revealed the Thornwaldt's cyst, suggesting that this modality may be more sensitive in detecting and evaluating cystic lesions of the nasopharynx. The differential diagnosis of cystic nasopharyngeal masses is discussed.

Adult↗
PubMed1978

Stability of glutaraldehyde disinfectants during storage and use in hospitals.

The problem of alkaline and acid glutaraldehyde disinfectants degradation (loss in active ingredients) during both extended shelf storage and continuous daily use under hospital practice was investigated. Glutaraldehyde disinfectants lose their potency due to three main types of reactions: aldol condensation, hydration-polymerization, and oxidation. The relative magnitude of each depends upon many variables, such as pH, dissolved gases content, and temperature. Room temperature aging studies of commercial potentiated acid glutaraldehyde (2% and 10% Sonacide) showed that the maximum loss in active ingredients is on the order of 7 per cent after 24 months. The newest type of stabilized alkaline glutaraldehyde (2% Cidex-7) loses 14 to 18 per cent of its active ingredient one month after buffer is added. Standing at room temperature, both alkaline and potentiated acid glutaraldehyde solutions generally drift towards lower pH. Several experiments and a literature search were conducted to assess the glutaraldehyde loss in alkaline and potentiated acid glutaraldehyde disinfectants under normal operating conditions in hospitals. Three independent studies showed that under continuous daily use in hospital buckets potentiated acid glutaraldehyde lasted twice as long as the alkaline glutaraldehyde formula. It was also noted that after weeks of continuous use the pH of both acid and alkaline formulas drifted towards neutrality. A six hospital study of potentiated acid glutaraldehyde in the Cidematic disinfecting machine showed that under a wide range of operating conditions it would take approximately four weeks of continuous daily use to reduce by half the concentration of active di-aldehyde.

Aldehydes↗
PubMed1971

Ultrasonic synergistic effects in liquid-phase chemical sterilization.

New methods of sterilization employing a chemical with moderate heat and ultrasonic energy have been devised. Inactivation of high-density bacterial spore suspensions is achieved by treatment with low concentration aqueous acid glutaraldehyde solutions at temperatures above or about 54 C. Low (20 kHz) or high (250 kHz) frequency ultrasonic energy is synergistic with glutaraldehyde. Rapid inactivation may also be achieved by using ultrasonic energy and aqueous alkalinized glutaraldehyde solutions at low (25 C) or moderate (55 C) temperatures. If compared to present room temperature techniques, "surface sterilization" time for contaminated objects can be reduced from hours to minutes.

Aldehydes↗
PubMed1967

Synergistic effects in sonochemical sterilization.

The synergistic effects observed during the sterilization of Bacillus subtilis var. niger ATCC 9372 by the combined action of ethylene or propylene oxide with high-intensity airborne sound waves (34.8 kc/sec) were investigated. It has been shown that the number of surviving spores deposited on paper strips decreases exponentially with the sound intensity at sample level. Reductions of the order of one-third of the time required for standard propylene oxide sterilization have been observed by using the combined action of sound waves with gaseous sterilization. At the present time, maximal synergistic effects seem to be achieved for the following experimental conditions: propylene oxide concentration, 500 to 1,000 mg/liter; acoustic intensity, 161 to 162 db; contact time, 80 min; temperature, 60 C; and relative humidity, 40%. The basic mechanism involved in sonochemical sterilization seems to be more of a physical (accelerated gas diffusion) than a chemical nature.

Bacillus subtilis↗
PubMedDate not supplied

Virucidal efficacy of hospital disinfectants and antiseptics.

This article reviews the virucidal efficacy of the five main families of chemical disinfecting solutions: Alcohols, glutaraldehydes, iodophors, bisdiguanides and phenolics currently used in hospitals as disinfectants or antiseptics. Special emphasis was placed on the efficacy of these solutions against difficult-to-kill hydrophilic viruses, some of which are responsible for nosocomial infections in hospitals.

Cross Infection↗