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Changes in skin collagen structure were studied after i.p. injection of phenylalanine mustard to rats. First order amino groups of lysine and arginine reacted with phenylalanine mustard, as stated potentiometrically. Bacterial collagenase was used to solubilize the skin collagen, and the aldehyde content of this material was measured using N-methyl benzothiazolone hydrazone. The aldehyde content was decreased in the collagen from rats skin after phenylalanine mustard injection. The observed changes in collagen may be analogous to the effect of aging, wherein collagen cross-linking is strengthened although qualitative changes in cross-linking may lower the measurable aldehydes.

The copper and zinc concentrations in 44 malignant and 48 nonmalignant women tissue samples of reproductive organs in women were measured. In malignant samples, the mean copper concentrations were 110%, 76%, and 38% higher for cervix, endometrium and ovary than the nonmalignant ones. The zinc concentrations in the analysed malignant tissues were lower than that in the corresponding nonmalignant tissues. The results of superoxide dismutase activities determinations demonstrate a considerable lowering of the enzymatic capacities to remove free oxygen radical in malignant tissues. A hypothesis for possible mechanism involving elevated copper concentrations, and decreased zinc concentrations, which may be responsible for malignant processes, are presented.

In 45 patients suffering from acquired valvular heart disease (a.v.h.d.) and in 20 controls blood serum levels of copper (Cu2+), ceruloplasmin (Clp), hydroxyproline (Hypro), hydroxylisine (Hyliz), collagen-like protein (Col-p), and daily urine excretion of Cu2+, Hypro, Hyliz and glycosamino-glicans (GAG) were determined. The comparison of the obtained mean values has shown that blood serum levels of Cu2+, Clp, Hypro, Hyliz, Col-p in the studied patients were statistically significantly higher than those found in controls, and the values of daily urine excretion of Cu2+, Hypro, Hyliz, GAG behaviour were similar. There were no significant differences between active and inactive processes and between infective and rheumatic endocarditis excluding GAG urine excretion. These elevated collagen degradation products provide evidence for disturbed collagen metabolism and confirm our previous biochemical, histopathological and ultrastructural examinations of connective tissue in patient with a.v.h.d. They also indicate that general collagenopathy might be the primary cause of a.v.h.d.

Phospholipase A2 activity was significantly increased in placental homogenates from 22 patients with preeclampsia in comparison to placental homogenates from women with uncomplicated pregnancy. Such an abnormality may be responsible for a altered release of free arachidonic acid, thus playing a major role in the pathogenesis of this syndrome.

20 healthy primigravidas were studied from 28 weeks' gestation until 4 days after delivery. In 9 of these women pre-eclampsia developed, the remaining 11 subjects who were age-matched had normal pregnancies. Plasma retinol, beta-carotene and vitamin E concentrations were measured by high performance liquid chromatography. The concentrations of retinol and vitamin E were significantly lower in the pre-eclampsia group than in the normotensive group at 28 weeks' gestation--that is before the onset of symptoms and signs of pre-eclampsia. The concentrations of retinol and vitamin E remained significantly lower in the pre-eclampsia group until delivery. It is suggested that measurement of the retinol or vitamin E concentration in plasma may be useful as a predictor of the likely development of pre-eclampsia.