A comparison of the effects of climbing fiber deafferentation in adult and weanling rats

The climbing fiber input to the cerebellar cortex was destroyed using both electrolytic and chemical (3-acetylpyridine) lesions. The long-term effects of climbing fiber deafferentation on the ansiform lobule of weanling and adult rats were examined at both the light and electron microscopic levels. Image analysis of Golgi-impregnated Purkinje cells indicated a significantly lower number of smooth branches and spiny branchlets following climbing fiber deafferentation of both adult and weanling rats. The results suggest that the lower number of smooth branches and spiny branchlets following climbing fiber deafferentation of the weanling rat is the result of a loss of postnatal growth rather than transneuronal degeneration. Ultrastructural evidence is provided in confirmation of these quantitative findings. Formation of ectopic dendritic spines was found following climbing fiber deafferentation of the weanling rat, but not the adult. It is shown that ectopic spines and the denervated dendritic thorns of these animals were synaptically innervated by the parallel fiber system and basket axons. The formation of ectopic spines on climbing fiber deafferentated Purkinje cells may represent a form of dendritic plasticity. Ultrastructurally, the dendritic arborizations of weanling deafferentated Purkinje cells showed no signs of transneuronal degeneration. However, the primary response to climbing fiber deafferentation in the adult rat was marked transneuronal degeneration of the Purkinje cell dendrites. It is suggested that the inability of the adult Purkinje cell to form ectopic spines and to replace the excitatory postsynaptic potential of the climbing fiber varicosity is directly related to the Purkinje cell's subsequent transneuronal degeneration.     

Autosomal recessive idiopathic torsion dystonia in a kindred of mixed ancestry

A family with idiopathic torsion dystonia (dystonia musculorum deformans) was seen in a peripheral clinic in the Richtersveld in the north-western Cape. This rare inherited form of neurological disease has maximal prevalence in individuals of Ashkenazi Jewish ancestry, and there is controversy regarding the exact mode of inheritance. The kindred documented in this study was of mixed ancestry (Cape Coloured), and autosomal recessive inheritance was suggested by the finding of affected male and female siblings born to normal parents in an isolated inbred community.     

'Reprofessionalization' or 'occupational imperialism'?: some reflections on pharmacy in Britain

Drawing upon preliminary research findings, this paper considers whether pharmacists in Britain face a crisis in their occupational status and identity as a result of changes in their work and market situations. It further examines some of the ways in which they are responding to the challenges and opportunities presented. The paper also comments on the utility of the concepts of 'reprofessionalization' and 'occupational imperialism' in the study of British pharmacy.     

Assessment of caffeine exposure: caffeine content of beverages, caffeine intake, and plasma concentrations of methylxanthines

The caffeine content of all tea or coffee beverages consumed by 17 healthy adults over 24 hours was measured. Plasma caffeine, theophylline, theobromine, and paraxanthine concentrations were determined over the same 24 hours. The average caffeine content per drink was 60.4 +/- 21.8 mg for instant coffee (14-fold range), 80.1 +/- 19.2 mg for brewed coffee (2.8-fold range), and 28.8 +/- 13.7 mg for tea (5.5-fold range). The number of drinks of coffee and tea consumed was a poor index of actual caffeine intake (r2 = 0.42). Caffeine intake correlated poorly with the 24-hour average caffeine concentration (r2 = 0.41), but there was a very good correlation between a single plasma caffeine concentration measured at 5 PM and the 24-hour average concentration (r2 = 0.94). The same was true for paraxanthine (r2 = 0.86). Paraxanthine accounted for 67.3% of the total dimethylxanthines in plasma, while theobromine and theophylline accounted for 24.4% and 8.3%, respectively. Mean caffeine clearance was 1.2 +/- 0.3 ml/min/kg. Plasma caffeine concentration before the first drink in the morning correlated very poorly with caffeine clearance (r2 = 0.07), even when adjusted for caffeine intake (r2 = 0.21).     

Kinetic fluorometric determination of aluminum in serum

We describe a simple fluorometric method for determining aluminum in serum samples by monitoring the rate of reaction of 2-hydroxy-1-naphthaldehyde-p-methoxybenzoylhydrazone with aluminum ions. The emission of the resulting fluorescent metal-chelate formed is measured at 475 nm. Aluminum was measured in the supernate of serum after proteins were removed by precipitation with concentrated nitric acid, and calculations were based on the technique of standard additions. Within-run precision (CV) was 7.8% and 4.8% at mean aluminum concentrations of 7.7 and 60.7 micrograms/L, respectively (n = 10); between-run precision (CV) was 8.9% and 5.7% at mean aluminum concentrations of 23.3 and 46.8 micrograms/L, respectively (n = 10). The standard curve for the method is linear over the range of 0-250 micrograms of aluminum per liter. Samples from 49 patients were analyzed for aluminum by the proposed method (y) and by electrothermal atomic absorption spectroscopy (x). Linear regression analysis of the results yielded the equation y = 0.98x + 2.3 (r = 0.989, Syx = 6.7). The proposed method is comparable in sensitivity to the well-accepted atomic absorption spectrometric method but is simpler and less expensive.     

Assessment of value of glycosylated albumin and protein in detection of gestational diabetes

There is a recognized need for the early detection of gestational diabetes, and a single blood test, if reliable, would be advantageous. Because serum albumin and total protein are glycosylated and have short life spans, we investigated the usefulness of glycosylated albumin and glycosylated protein in the detection of gestational diabetes. We studied five groups, each with 20 subjects: nonpregnant and pregnant controls, nonpregnant and pregnant insulin-dependent diabetic (IDDM) patients, and gestational diabetic patients. All patients with no history of diabetes had an oral glucose tolerance test to define their carbohydrate status. Our results showed that percent glycosylated albumin and percent glycosylated protein were significantly elevated in both groups of IDDM patients compared with the other groups. However, gestational diabetic patients had glycosylated albumin and glycosylated protein values similar to those of both control groups. Both glycosylated albumin and glycosylated protein correlated well with HbA1c determinations. Thus, glycosylated albumin and glycosylated protein may be a good index of glycemic control, but they are of little value in the diagnosis of gestational diabetes because of a lack of sensitivity: 8 and 3% for glycosylated albumin and glycosylated protein, respectively.