Skin reactions to irritants assessed by non-invasive bioengineering methods

Pathophysiological components of irritant contact dermatitis caused by 3 chemically-different irritants were investigated. 20 healthy volunteers were patch tested with sodium lauryl sulphate, nonanoic acid and hydrochloric acid on the flexor side of the upper arm. The skin response was evaluated after 24, 48 and 96 h by visual scoring and measured by the following bioengineering methods: transepidermal water loss measurement, electrical conductance for measurement of skin hydration, laser Doppler flowmetry for measurement of cutaneous blood flow and 20 MHz ultrasound A-scan for measurement of skin thickness. In spite of homogeneous inflammatory responses, significant differences in the severity of the injury to the skin barrier function caused by the different irritants were found. Also significant differences between irritants were found in the time course of development of maximum irritant reactions. Bioengineering methods indicating inflammatory responses (measurement of blood flow and skin thickness) were helpful in quantifying the irritant response in general, while bioengineering methods indicating epidermal damage (measurement of TEWL and electrical conductance) were helpful in classifying the individual irritants.     

Threshold for occluded formaldehyde patch test in formaldehyde-sensitive patients

Our purpose was to investigate the eliciting threshold concentration of formaldehyde in formaldehyde-sensitive individuals in the occluded and non-occluded patch teat and to evaluate the relationship in repeated open application test (ROAT) with a product containing a formaldehyde releaser. 20 formaldehyde-sensitive patients and a control group of 20 healthy volunteer were included in the study. Occluded and non-occluded patch tests with formaldehyde solutions form 25 to 10,000 ppm. and ROAT for I week with a leave-on cosmetic product containing on average 300 ppm formaldehyde. Were carried out simultaneously on each subject. In the occluded patch test. 1/2 of the 20 patients only reacted to 10,000 ppm formaldehyde. 9 reacted to 5,000 ppm. 3 reacted to 1.000 ppm. 2 reacted to 500 ppm and I reacted to 25 ppm. No definite positive reactions were observed in the non-occluded patch test or in the ROAT No positive reactions were observed in the control group to any of the test procedures. We concluded that the threshold concentration for occluded patch test to formaldehyde in formaldehyde-sensitive patients was 250 ppm. The threshold in occluded patch test corresponded to the degree of sensitivity Definite positive reactions in the ROAT were not seen, either indicating that they are unlikely to happen with the type of product used or that the exposure time was too short.     

Accuracy of radiologic and endoscopic diagnosis of gastric ulcer

Patients with upper abdominal pain are often examined with both double contrast study of the stomach and endoscopy. On the basis of the results of the two examinations four diagnostic criteria of an ulcer can be formed: 1) radiography reveals an ulcer, 2) endoscopy reveals an ulcer, 3) both radiography and endoscopy reveal an ulcer, and 4) radiography and/or endoscopy reveals an ulcer. In a prospective study the accuracy of each of the four diagnostic criteria was examined. Eighty-two randomly selected outpatients had a double contrast barium examination and an upper gastrointestinal endoscopy performed by staff personnel. The diagnosis of a specialist in upper gastrointestinal endoscopy was used as the standard. For the four diagnostic criteria the overall accuracy ranged from 0.80 to 0.88. The predictive value of a positive test result was around 0.70 and the predictive value of a negative test result ranged from 0.81 to 0.96. The specificity ranged from 0.87 to 0.95, and the sensitivity from 0.38 to 0.90. It is concluded that from a clinical point of view, the accuracy of the four diagnostic criteria does not differ to an extent that justifies recommendation of one diagnostic criterion of gastric ulcer rather than the other.     

Perseveration and wandering as a predictor variable after brain injury

Perseveration and wandering are well recognized sequelae of traumatic brain injury. They are believed to arise as a constellation of behaviours from lesions involving the frontal, temporal, or parietal lobes or subcortical motor regions. Attention and memory deficits are believed to contribute to the presence of perseveration and wandering. Patients who perseverate and or wander after brain injury tend to have poorer outcomes and slower rates of progress. This prospective study is based on 32 consecutive admissions to a brain injury rehabilitation unit over a 4 month period. For each patient data was collected on perseverative behaviours, wandering, Functional Independence Measure, total number of rehabilitative days, supervision requirement at discharge and discharge disposition. Perseveration and wandering were assessed using the Agitated Behaviour Scale and clinical observations of the primary physician, physical and occupational therapist and speech language pathologist. Correlations between perseverative and wandering behaviours were made with the variables identified.