[Somatomedin-type activity of Biomin H]. / Prítomnost somatomedínovej aktivity v preparáte Biomin H.

In the biopreparation Biomin H, which is prepared from eggs, somatomedin activity was tested. The activity was not substantially affected by thermal processing at 36 degrees C-130 degrees C; the highest concentration of somatomedin activity was at a concentration of 30 mg Biomin H in the reaction mixture. The authors discuss the necessity to analyze the nature of somatomedin activity by detection of selected known growth factor (IGF-I, IGF-II, TGF-beta).

[Blood somatomedin levels in neonates with congenital hypothyroidism and phenylketonuria]. / Hladiny sérového somatomedinu u novorozencu s kongenitální hypotyreózou a fenylketonurií.

A biological method was employed for assessing the somatomedin activity (SM)-IGF I-somatomedin C: 1) in 13 10 to 23-day old children with congenital hypothyroidism (CH) before starting substitution therapy with L-thyroxine and after one month lasting therapy. SM levels were significantly lower prior to the onset of therapy than in a control group (for p less than 0.01 on 1% level). The SM levels in treated children did not differ from controls. 2) 16 children with classic phenylketonuria (PKU) were also examined of the age of 12-23 days before starting dietary treatment with restricted phenylalanine (Phe). When compared with a control group SM levels were significantly lower in the PKU group (p = 0.01 on 5% level). When stable serum Phe concentrations had been obtained, following restricted Phe intake, SM levels no longer differed from the control. However statistical correlation of Phe and SM levels was not attained.

[Dual-photon densitometry of the lumbar spine. Further experience and findings]. / Dvoufotonová denzitometrie bederní pátere. Dalsí zkusenosti a poznatky.

The authors submit further experience with two-photon absorption measurement of the mineral content of the lumbar spine using a NOVO/Lab BMC 22a (Denmark) apparatus. 1. The authors discuss the problem of evaluation of results in postmenopausal women. For the basic evaluation the authors use the range +/- 2 s of "normal" values classified by decades; another suitable guide to the interpretation could be extrapolation of the lower range of the regression zone in recorded in premenopausal women to higher age groups. 2. The histogram of frequencies of normal values in women in g.cm-2 has two peaks corresponding to the group of premenopausal women and the group of postmenopausal women. 3. Of 573 examined patients with osteoporosis 295, i. e. 51.5%, cannot be reliably evaluated or cannot be evaluated at all (as a rule because of changes of the spine). Of 49 results obtained in men with osteoporosis 34.7% are within the normal range, of 229 results obtained in women with osteoporosis 47.2% are within the normal range. The hitherto assembled experience is consistent with the view that the method is useful and invaluable in particular for the long-term follow up of patients.

[Dual-photon densitometry of the lumbar spine. Basic experience and results]. / Dvoufotonová denzitometrie bederní pátere. Základní zkusenosti a výsledky.

The principle of assessment of absorption of gamma radiation (single photon radiation, i.e. with one radiation energy) was first applied to assess the content of mineral substances in peripheral bones. Earlier and more marked affection of the spine in osteoporosis led to the development of dual-photon densitometry, i.e. differential assessment of the absorption of gamma radiation with two energies, which makes it possible to eliminate the ratio of soft tissues in absorption of the radiation (the source of radiation is gadolinium 153Gd). The equipment is more complicated and more expensive, the operation more time consuming and more pretentious. Various circumstances - most frequently changes of the spine with foci of increased density - make it difficult or impossible to evaluate and use the results in one third of patients with disorders of the bones (most frequently osteoporosis), incl. 1/2 of the patients above 60 years of age. Short-term reproducibility of the estimations is satisfactory - variation coefficients of repeated measurements in g.cm-1 and in g.cm-2 are less than 2%. Examination of 183 controls (83 men, 100 women) indicates a drop of the mineral content in L2 to L4 with age in women from 25 to 30 years to old age with a slight acceleration during the menopause, in men a decline only after the age of 60 years. In younger age groups the scatter of our normal values in men is greater than in women. The bone density in g, g.cm-1 as well as in 9.cm-2 rises significantly in the order L2 less than L3 less than L4. Except for the limited applicability of results the basic experience is on the whole favourable. From the clinical aspects the evaluation of pathological findings, to which a separate paper will be devoted, is of decisive importance.

Effect of human growth hormone and somatomedin on the recovery of sheep red blood cell receptor in peripheral T-lymphocytes.

The effect of growth hormone (GH) and somatomedin (SM) on the recovery of sheep red blood cell (SRBC) receptor in trypsinized human T-lymphocytes was studied either with the use of sera from patients with acromegaly or pituitary dwarfism or after the addition of exogenous GH, SM or thymosin to human sera. It was found that GH does not show any effect on the recovery of SRBC receptor, but it may act through the increase of SM level. It was concluded that the regulation of cellular immunity may be influenced by GH through its stimulatory action on the synthesis and release of somatomedins.

Effect of thyroid function on serum somatomedin activity.

UNLABELLED: To obtain more information about a possible role of somatomedins in mediating the effects of thyroid hormones on the development and function of epiphyseal cartilage, somatomedin activity, measured on the basis of 35S incorporation in embryonic chick cartilage, was studied in thyrotoxic patients before and after treatment with carbimazole or surgery and in a group of patients with primary hypothyroidism. In 29 hyperthyroid patients mean values of somatomedin were 1.29 +/- 0.03 SEM an differed significantly (P less than 0.01) from normals (1.04 +/- 0.03). In 15 carbimazole treated patients and in 5 operated patients with thyrotoxicosis somatomedin levels fell from 1.29 +/- 0.04 to 1.03 +/- 0.04 (P less than 0.01) when the patients became euthyroid. Correspondingly, somatomedin levels in 12 untreated hypothyroid patients (0.82 +/- 0.04) were significantly less than in normals (P less than 0.01) an increased from 0.77 +/- 0.09 to 1.14 +/- 0.13 (P less than 0.05) in 4 patients on replacement therapy. IN CONCLUSION: somatomedin levels rise when thyroid hormones are present in excess, and fall when these are deficient. This suggests that thyroid hormones are important regulators of somatomedin levels.

Effect of autonomic blockers on the heart rate of intact rats and animals with artificial hyperthyroidism.

The effect of various autonomic blockers on the heart rate (from the ECG recording) of intact rats and of animals with experimental hyperthyroidism induced by the administration of dried thyroid was studied. In intact rats, the heart rate fell significantly (by 22%) during the first week after the peroral administration of propranolol (0.05% in food), but trimepranol (0.02%), reserpine (0.001%) and guanethidine (0.1%) had no effect (in a suplementary experment, a small, but statistically significant decrease was also found after trimepranol). In experimental hyperthyroidism, using the same blocker doses, the heart rate fell significantly after propranolol (by 23%), trimepranol (22%), reserpine (16%) and, in a preliminary experiment, guanethidine (19%). On injecting 0.05 mg propranolol intravenously, the maximum drop in the heart rate in intact rats was 22%, while in hyperthyroidism it was hardly more than half this value (at all the intervals from 2 to 30 minutes the decrease was statistically significant). Practolol, in a dose of 0.3 mg i.v., was less effective -- in intact rats the heart rate fell by not more than 12% (at all the intervals from 2 to 30 minutes the decrease was significant), but in hyperthyroidism the drop was slower and statistically non-significant. The results do not furnish an unequivocal answer to the question of the role of adrenergic regulation of the heart rate under physiological conditions and in experimental hyperthyroidism in rats.