The periodontal condition of a cross-section of individuals aged between 15-59 years was characterised from clinical and radiographic observations of dental calculus, gingival inflammation, the level of the gingival attachment , alveolar bone loss, teeth missing or requiring extraction for periodontal reasons. The common characteristics of the profile in Tonga and W. Samoa were a high prevalence of the factors common to periodontal disease: calculus and gingival inflammation; a progressive apical movement of the gingival attachment; and alveolar bone loss. All these criteria showed a positive age dependency with calculus (particularly subgingival calculus) and gingival inflammation being very commonly associated with all tooth types at an early age, less than 30 years. Tooth loss observed was presumed to be previously associated with periodontal disease because the prevalence of dental caries was very low in both populations. Substantial differences were observed in the number of missing teeth between Tongan and Samoan populations, the Tongan subjects having a high rate of tooth loss. From radiographic interpretations of the periodontal conditions fewer subjects in Tonga were assessed as having no disease, and there was a higher prevalence of progressive destructive disease in Tonga than in W. Samoa. The proportion of subjects in both countries with no disease decreased rapidly with age. There was no evident explanation of the greater severity of disease in Tonga than in W. Samoa. The prevalence of microbial plaque, calculus and gingival inflammation was very high in all subjects at all ages particularly over 30 years in both populations.

To investigate the role of high-intensity intermittent exercise on adaptations in blood volume and selected hematological measures, four male subjects aged 19-23 yr [peak O2 consumption (VO2max) = 53 ml X min-1 X kg-1] performed supramaximal (120% VO2max) cycle exercise on 3 consecutive days. Each exercise session consisted of intermittent work performed as bouts of 1-min work to 4-min rest until fatigue or until a maximum of 24 repetitions had been completed. Measurements on blood samples were made before the exercise period and 24 h after the last exercise session. Plasma volume (PV) estimated using 131I-human serum albumin increased by 11.6% (3,504 vs. 3,912 ml; P less than 0.05). Total blood volume (TBV) based on PV and hematocrit (Hct) values increased by 4.5% (5,798 vs. 6,059 ml; P less than 0.05), whereas red cell volume (RCV) decreased by 6.4% (2,294 vs. 2,147 ml; P less than 0.05). Measurements of hematological indices indicated significant reductions (P less than 0.05) in whole-blood Hct (39.7 vs. 35.5%), hemoglobin concentration (15.5 vs. 13.9 g/100 ml), hemoglobin content (897 vs. 839 g), and red blood cell count (5.15 vs. 4.55 X 10(6) X mm-3). The findings of this study suggest that exercise intensity is a major factor in promoting exercise-induced hypervolemia and that rapid elevations in PV can be induced early in training.

The pharmacokinetics of ciprofloxacin following a single 100 mg oral dose were evaluated in elderly patients (mean age 74 years), laboratory staff (30-40 years) and students (less than 20 years). There were no significant differences in serum Tmax (1.2-1.3 h) or in overall serum elimination half-life (3.7-4.0 h) but Cmax in elderly patients was more than double that in young volunteers (P less than 0.005). The serum AUC value was greater both in fasting students (1.4 mg/h/l) compared with the same subjects after food (1.09: P less than 0.01) and, after food, in elderly patients (1.95) compared with students (0.81: P less than 0.005). Urinary recoveries were greater in fasting subjects and in all categories of volunteers compared with elderly patients. However, in the elderly, urinary ciprofloxacin concentrations (0-6 h mean 66 mg/l: range 17.4-200 mg/l) were more than adequate for the eradication of urinary pathogens.

Fibre type distributions in the vastus lateralis muscles of six male subjects (age 18 to 22 years) have been compared at rest and during exercise. Exercise consisted of one leg cycling at 60% VO2 max (one leg) for 120 min. The increased contractile activity was associated with a 28.8% (p less than 0.05) decrease in the distribution of Type I fibres in the exercised leg. This change in fibre type distribution was manifested early in the exercise (15 min), and was also evident in muscle samples obtained after 60 and 120 min of activity. Reductions in the Type I fibre distribution was accompanied by an increase in the Type II fibres, specifically the Type IIA distribution (p less than 0.05). Comparable alterations in the specific fibre distribution were also found in the non exercising leg. These observations indicate that alterations in the muscle cell induced either directly or indirectly by the increased contractile activity interact with normal pre-incubation conditions to effect changes in the stability of the myofibrillar ATPase reaction. Specifically, it appears that a percentage of the Type I fibre population becomes acid labile and alkali stable.

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