Biotransformational and neurophysiological changes in rabbits exposed to lead

Lead was administered to adult male rabbits in drinking water at a 0.1% concentration for four and five week periods. The lead contents were determined in the central and peripheral nervous tissues and in the liver, kidney, and intestinal mucosa. The conduction velocity of sciatic nerve and the activities of drug metabolizing enzymes in other tissues were determined. The lead concentration in the blood was at a steady state at four to five weeks of exposure. Lead accumulated in all tissues except the brain. The brain lead concentration was 40 to 50% of that in the blood, indicating the existence of a blood-brain barrier. However, the lead concentration in the sciatic nerve increased significantly from four to five weeks of exposure and exceeded that in the blood. This indicates the lack of a blood-nervous tissue barrier in the sciatic nerve allowing a continuous accumulation of lead. This accumulation affected the function of the sciatic nerve; motor nerve conduction velocity decreased from the control level (58.3±7.4 m/sec) to 43.8±6.3 m/sec after the four-week exposure and to 35.0 ± 1.3 m/sec at 5 weeks of exposure. After five weeks of exposure, no changes in the hepatic, intestinal, or renal drug metabolizing enzyme activites were found. These results suggest that motor nerve conduction velocity is affected by lead exposure prior to any influence on biotransformation enzymes.     

Fall-related injuries among initially 75- and 80-year old people during a 10-year follow-up

The aim of this study was to investigate the occurrence, type, scene and seasonal variation of fall related injuries, and the impact of socio-economic factors, mobility limitation, and the most common diseases on the risk of injurious falls over a 10-year follow-up. Elderly residents of Jyv?skyl?, Finland, aged initially 75 and 80 years, took part in the study in 1989-1990. The health and functional capacity assessments were carried out at the baseline. Injurious falls were monitored over a 10-year period. The rate of injurious falls per thousand person-years was 188 among women and 78 among men. Of all fall-related diagnoses, head injuries comprised 32%, upper limb injuries 27% and hip injuries 19%. Majority of injurious falls took place indoors and no seasonal variation in fall occurrence was observed. Recurring falls were more likely to take place in institutions. Osteoarthritis increased the risk of injurious falls but no effect was observed for coronary heart diseases or mobility limitation. All in all, intrinsic factors, such as chronic diseases and mobility limitation had only minor effect on risk of injurious falls among older people. The current results suggest that preventive interventions for injurious falls among older people should pay attention to the risk factors present indoors.     

Effect of Physical Activity Counseling on Disability in Older People: A 2‐Year Randomized Controlled Trial

OBJECTIVES: To study the effect of a physical activity counseling intervention on instrumental activity of daily living (IADL) disability. DESIGN: Primary care–based, single‐blind, randomized controlled trial. SETTING: City of Jyväskylä, central Finland. PARTICIPANTS: Six hundred thirty‐two people aged 75 to 81 who were able to walk 500 meters without assistance, were at most moderately physically active, had a Mini‐Mental State Examination score greater than 21, had no medical contraindications for physical activity, and gave informed consent for participation. INTERVENTION: A single individualized physical activity counseling session with supportive phone calls from a physiotherapist every 4 months for 2 years and annual lectures on physical activity. Control group received no intervention. MEASUREMENTS: The outcome was IADL disability defined as having difficulties in or inability to perform IADL tasks. Analyses were carried out according to baseline IADL disability, mobility limitation, and cognitive status. RESULTS: At the end of the follow‐up, IADL disability had increased in both groups (P<.001) and was lower in the intervention group, but the group‐by‐time interaction effect did not reach statistical significance. Subgroup analyses revealed that the intervention prevented incident disability in subjects without disability at baseline (risk ratio=0.68, 95% confidence interval=0.47–0.97) but had no effect on recovery from disability. CONCLUSION: The physical activity counseling intervention had no effect on older sedentary community‐dwelling persons with a wide range of IADL disability, although it prevented incident IADL disability. The results warrant further investigation to explore the benefits of a primary care–based physical activity counseling program on decreasing and postponing IADL disability.     

Supervised toothbrushing and oral health education program in Kuwait for children and young adults with Down syndrome

The authors report on the effectiveness of a school-based, supervised toothbrushing program among a group of 112 children with Down syndrome in Kuwait. The study involved 45 boys and 67 girls, who ranged in age from 11–22 years (mean, 14.8 years). The participants had moderate mental retardation and attended one of two special needs schools. Plaque was scored according to the Silness and Loe plaque index and gingivitis according to the Loe and Silness gingival index. Supervised toothbrushing and dental health education sessions were conducted twice a week. The program was evaluated at the end of three months. The mean plaque score decreased from 1.93 to 0.95 (p < 0.001), and the mean gingival score from 2.00 to 0.83 (p < 0.001). This three-month supervised toothbrushing program was effective in reducing plaque and gingivitis scores, but the key to long-term success of the program is sustaining the children's motivation to make oral hygiene a part of their daily life.     

Effect of chyme on mucosal enzyme levels in small intestine of the rat

Partial jejunectomies, gastrojejunostomies (with closed pylorus), and jejunal Thiry-Vella loops were made in order to elucidate the role of chyme in the control of mucosal mass and the activities of alkaline phosphatase, ATPase, and maltase in the small intestine of the rat. After partial jejunectomy, a partially reversible mucosal hyperplasia was seen in the small intestine with the exception of distal ileum. After gastrojejunostomy a similar hyperplasia took place in the jejunum and proximal ileum. In the jejunal Thiry-Vella loops a mucosal atrophy was found in 4 wk. After partial jejunectomy the activity of alkaline phosphatase decreased slowly in 4 wk in the remaining small intestine with the duodenum as an exception. ATPase activity decreased in the duodenum. Maltase activity remained unchanged during 8 postoperative wk. In gastrojejunostomized rats the activity of alkaline phosphatase and ATPase increased slowly during 12 wk in the jejunum aborally from the gastroenterostomy. A slight depression of maltase activity was observed in the operation area and a slight increase of enzyme activity was found in the middle of the small intestine. In jejunal Thiry-Vella loops the activity of alkaline phosphatase decreased, but no change of maltase activity could be observed during 4 wk. Perfusion of a loop with maltose solution did not cause any changes in the activity of alkaline phosphatase or maltase. The results indicate that after a change in chyme passage the adaptation takes place in the small intestine primarily by the change of mucosal mass, and at least some enzyme levels in the mucosal cells are remarkably stable.     

Treatment of cholecystitis: Cholecystostomy or cholecystectomy?

Nine hundred ninety-two consecutive patients with cholelithiasis and cholecystitis are reported on. In Finland, these diseases seem to affect women more often than men as only 18 per cent in the present series were men.The frequency of these diseases increases with advancing age and reaches its peak in patients sixty to sixty-five years of age.Therapy always consisted of cholecystectomy. The incidence of minor technical complications varied from 1.1 per cent in group I to 4.5 per cent in group III (6.1 per cent in group IIB). Postoperative nonfatal complications varied from 2.0 per cent in group I to 5.2 per cent in group III (8.1 per cent in group IIB).The age-adjusted duration of postoperative hospitalization was about eight days (in group IIB, nine days). In groups I and II one patient died whereas in group III two died. The mortality varied from 0.2 per cent in group I to 0.6 per cent in group III (1.2 per cent in group IIB). The overall mortality for this series was 0.5 per cent.On the basis of this analysis and the good results, I have concluded that cholecystectomy is the preferred therapy for cholecystitis at all stages when all coexisting diseases and water and electrolyte imbalances have been treated.     

Effect of administration route of ddt on acute toxicity and on drug biotransformation in various rodents

DDT was administered to the guinea pig, mouse and rat either ig or ip and to the hamster ig in order to investigate variations in the response of hepatic and duodenal drug-metabolizing enzymes to DDT. The intragastric dose (160 mg/kg) was found to produce gastric bleeding and severe tremor in rats and mice but not in other rodents. The hepatic aryl hydrocarbon hydroxylase activity and cytochrome P-450 concentration decreased after the ig administration of DDT to rats, mice and guinea pigs but in hamsters the activity of aryl hydrocarbon hydroxylase and cytochrome P-450 concentration increased 12 hr after the dosage. The aryl hydrocarbon hydroxylase activity decreased also in the duodenal mucosa of the rat after the ig administration of DDT. The ip dose had no effects on the hepatic or duodenal monooxygenase system in 12 hr. The UDPglucuronosyltransferase activity was slightly lowered in hepatic microsomes of the rat and mouse after the ig dose of DDT, but the decrease was more profound when measured afterin vitro trypsin digestion of microsomes. The trypsin digestion activated the hepatic UDPglucuronosyltransferase in all the species studied,i.e., guinea pig, hamster, mouse and rat (3-, 3-, 5-, and 8-fold, respectively). The duodenal UDPglucuronosyltransferase activity was not affected by DDT administration in any of the species studied. The results suggest that the acute toxic effects of DDT are species-dependent and the administration route is important in DDT toxicity. The hydroxylation step in drug metabolism is more sensitive to DDT than the glucuronidation step.Presented at the Third International Congress of Pesticide Chemistry (IUPAC) Helsinki, Finland, 1974.     

Trends in the development of oral hygiene habits in Finnish adolescents from 1977 to 1981

The aim of this study (part of the Juvenile Health Habit Study) was to analyze changes in how frequently certain oral hygiene measures are used, namely toothbrushing and dental flossing in 1977-81. A representative sample of Finnish adolescents aged 12, 14, 16 and 18 yr old, were sent a postal questionnaire in February 1977 (n = 3209), another in February 1979 (n = 4953), and a third one in February 1981 (n = 4705). The response rates for the three questionnaires were 88%, 86% and 88%, respectively. During the years studied no systematic changes occurred in the toothbrushing frequency. When the background factors that are highly correlated with toothbrushing frequency (school career or school success of adolescents, householder's occupation and education, place of residence) were studied, no consistent changes were observed from 1977 to 1981. The percentage of adolescents who used dental floss daily did not change. However, the proportion of sporadic users of dental floss increased from 13% in 1979 to 24% in 1981. Dental health education had little effect on toothbrushing habits and its background variables, although the amount of time spent in dental health education during the same period had increased significantly. Programs of dental health education should be evaluated so that the situation can be improved in the future.