Inclusion body myositis. A "slow-virus" infection of skeletal musculature?

We report the case of a 56-years old patient with clinical symptoms of an unresolved neuromuscular disease. The light microscopic studies of a muscle biopsy from the m. triceps shows the picture of a diffuse muscular atrophy. By electron microscopy, myelin-like degeneration zones with tubular-filamentous inclusions can be shown in the cytoplasma of the atrophic muscle cells. These filamentous structures correspond morphologically to the nucleocapside of paramyxoviruses. These results lead, even without the proof of inflammatory cells, to the diagnosis of an "inclusion body" myositis also taking into account the clinical and electrophysiological findings.

[Treatment of primary hyperlipoproteinemias of type IIB and IV with butylbiguanide and clofibrate (author's transl)]

21 patients with primary hyperlipoproteinemias of type IIb and IV were treated for 8 weeks with placebo, 8 weeks with 0.3 g butylbiguanide and 1.5 g clofibrate/day and then for 8 weeks with 1.5 g clofibrate/day. In 12 patients a second placebo phase of 8 weeks followed. After 8 weeks of combined treatment with butylbiguanide and clofibrate the serum triglycerides decreased from 725 mg to 269 mg/100 ml. During the following period of clofibrate treatment the serum triglycerides increased after 4 and 8 weeks to 326 mg and 306 mg/100 ml respectively. The combined treatment with 0.3 g butylbiguanide and 1.5 g clofibrate/day is more effective in lowering elevated serum triglycerides and cholesterol than 1.5 g clofibrate alone.

Influence of hemithyroidectomy on endogenously labelled thyroxine and tri-iodothyronine in rats

In order to investigate the influence of thyroid-stimulating hormone (TSH) on the ratio of newly synthesized thyroxine( T4):tri-iodothyronine (T3), hemithyroidectomy was performed on rats maintained on an iodinerich diet. One and two weeks after the operation the concentration of TSH increased in the plasma. As a result, the weight of the residual lobes and their thyroidal uptake of 131I/mg increased and significant histological signs of increased function in the remaining lobes were observed. The most prominent effect was a significant alteration of the ratio of newly synthesized T4:T3 in favour of T3, both in the thyroid and plasma. Four weeks after the operation, when the residual lobes weighed 57% more than those in the controls, the alterations decreased or returned to normal. The total hormone concentration in the plasma (measured as protein-bound 127I) and the oxygen consumption of the animals remained unchanged during the entire study. These findings support the hypothesis that alteration of the production and secretion ratio of T4:T3 induced by TSH might act as another regulatory factor, if a hormone deficiency originates in the peripheral cells. The results show also that changes of the T4:T3 ratio induced by TSH occur in animals on an iodine-rich diet.

The effect of iodine deficiency and suppression of TSH secretion on radioiodine labelled thyroxine and triiodothyronine in the thyroid of rats

It has been suggested that TSH stimulation of the thyroid gland is accompanied by an alteration in the ratio of newly synthesized thyroxine (*T4)1)/triiodothyronine (*T3) in favour of *T3. Evidence in support of this hypothesis is provided here by the finding that suppression of TSH secretion in rats alters this ratio in the other direction, i. e. in favour of *T4.

Thus, endogenous TSH stimulation was increased for 4 weeks by iodine deficiency. Its suppression was performed by the administration of T3, using a dose of 0.05-0.25 μg/100 g body weight which was injected subcutaneously every 12 hours for three days. The effect of TSH stimulation and suppression could be assessed from the following parameters: thyroid weight and histology, thyroid 131I uptake, 131I conversion ratio, hormonal iodine concentration, and TSH level in the plasma. After iodine deficiency the ratio of *T4/*T3 in the thyroid gland changed in favour of *T3. This may compensate for the iodine deficiency, since the oxygen consumption and the heart rate of the animals remained in the normal range. After suppression the ratio of *T4/*T3 changed in the opposite direction, i. e. in favour of *T4. The extent of the suppression of *T4 and *T3 was dependent on the suppression dose used.