Effect of corticosteroids on elevated intracellular sodium, plasma lipid peroxide levels and reduced Na(+), K(+)-ATPase activity in patients of bronchial asthma.

In view of several reports that there is a lack of balance in free radicals in case of bronchial asthma (1) the effect of free radicals on cell membrane was studied by estimating the membrane bound protein Na(+), K(+)-ATPase activity and the intracellular sodium level in patients of bronchial asthma before and after a short course (one week) of oral corticosteroid (prednisolone 0.75-1mg/kg body weight) therapy. Results showed that there is a definite statistically significant rise in free radical level and intracellular sodium level and a significant lowering of Na(+), K(+)-ATPase activity in case of untreated bronchial asthma. After short course of therapy with oral corticosteroids, the free radical level and intracellular sodium level decreased significantly, together with a significant rise of the Na(+), K(+)-ATPase activity. Also, a significant negative correlation (r=-0.74) between the lipid peroxide level and the Na(+),-K(+)-ATPase activity was found in these cases.

Surveillance of problem drug use in the UK: a review of a Regional Drug Misuse Database.

BACKGROUND: We report detailed findings of the first systematic validation of a Regional Drug Misuse Database (RDMD); such databases constitute the main investment in routine drug statistics in the UK by the Department of Health. METHODS: A retrospective case-finding study in a stratified random sample of one in three specialist drug agencies was carried out. Agency records of clients attending during 1994 were matched with reports (episodes) to the North Thames RDMD to assess the level of under-reporting, and the relationship between RDMD reports (episodes) and the number of problem drug users in contact with agencies. Under-ascertainment of cases was estimated using two-sample capture-recapture. RESULTS: Under-reporting was associated with agency records missing full date of birth or initials (attributers), and agency type. Compared with drug dependency units (DDU) the odds of under-reporting were 3-18 times higher by the other specialist drug agencies. Even after excluding episodes with missing attributers the odds ratio (OR) of not being reported was significantly higher among needle exchanges (OR 2.7), non-statutory community based drug teams (OR 3.2), statutory community based drug teams (OR 4.9) and residential rehabilitation units (OR 8.7) compared with DDUs. Overall database episodes represented 60 per cent of the number of clients attending specialist agencies as a result of a mixture of under-reporting and the proportion of clients retained in treatment, which also varied by agency type. A total of 727 individuals (16 per cent) had never been reported. CONCLUSIONS: Surveillance of drug misuse through RDMDs does not yet fulfil its objectives. It is essential that a system of following up reports is introduced to improve their utility, and to contribute to the monitoring of the UK Government's new drugs strategy, and wider European surveillance.

Efficient and effective indirect bonding.

A new resin designed specifically for indirect bonding has been developed. Previous problems with indirect bonding systems, which were partly related to the fact that resins designed for direct bonding had to be used, have been addressed. A cohesive and complete system for fabricating bonding trays, and the indirect bonding procedure, is presented.

Preventing enamel decalcification after orthodontic treatment.

As enamel decalcification can occur in conjunction with orthodontic treatment, suggestions are offered for ways to prevent this condition from manifesting. A review of the literature shows the problem is widespread. Preventive programs must be emphasized.

Normal and abnormal temporomandibular joints as demonstrated by magnetic resonance imaging.

Magnetic resonance imaging of the temporomandibular joint (TMJ) was performed on two normal volunteer subjects and two symptomatic subjects using a 0.15 T resistive magnet. A spin echo pulse sequence with a TE of 38 ms and a TR of 500 ms was employed. The TMJ meniscus is a low signal structure, and the bilaminar zone behind it is a relatively high signal structure. In normal closed mouths, the demarcation between meniscus and bilaminar zone is located at the vertex position above the mandibular condyle. When the condyle translates, the posterior portion of the meniscus bulges into the joint space. Dislocated meniscus can be identified by a gray mass anterior to the condylar head. The joint space is filled with the higher signal of the bilaminar zone. In non-reducible dislocations, the meniscus remains anterior to the condylar head with opening of the mouth. Reduced dislocations appear similar to normal joints in the open mouth.

Canine root movement: an evaluation of root springs.

An analysis of the mechanics required for distal movement of canine roots is presented and, on the basis of this analysis, a specific clinical approach is outlined. Three different root spring designs were tested for their ability to meet the previously determined requirements. The only spring that approached the established requirements was spring A-2. Spring types B and C did not meet the established requirements. Angular activations in excess of 20 degrees in 0.018 by 0.025 inch stainless steel wire without benefit of a loop resulted in permanent deformation of the appliance.

Dimensional changes in the dental arches of orthodontically treated cases.

Integrated data from lateral cephalometric radiographs and study models of fifty-three patients were studied to assess the interactions between dimensional changes occurring during orthodontic treatment and the postretention stability of these changes. A new technique was developed to study distal movement of canines. Distal movement of canines did not ensure a stable increase in intercanine width. There was no significant relationship between mesiodistal position of the first molars and changes in intermolar width. Eruption of the first molar in the postretention period was associated with greater stability in overbite. There was no great degree of correlation between depth of the curve of Spee and inclination of the occlusal plane or between changes in arch length and changes in inclinations of the incisors.