Biomedical subjects
Publications and source records attributed to D Cramer.
A review of fossil mammalian faunas from the Middle Awash indicates they span most of the later Neogene and document evolutionary change in several mammalian groups, especially Primates, Proboscidea and Artiodactyla. Oldowan artefacts first appear in the late Pliocene, while Acheulian and later industries and apparent occupation sites occur in Pleistocene beds.
Twenty-five symptomatic postmenopausal women with an intact uterus were assigned in random double-blind fashion to receive 0.625 mg of conjugated estrogens on either a cyclic (3 weeks on, 1 week off) or continuous (daily) basis. The incidence of endometrial hyperplasia as demonstrated by screening biopsies at 6 and 12 months of therapy was 4.5 per 100 woman-months in the cyclic group and 3.7 per 100 woman-months in the continuous group (a difference not statistically significant). Thus, in this study, cyclic therapy was found to offer no advantage over continuous therapy. In our opinion, the rate of hyperplasia development in both groups unacceptably high, and efforts must be directed at reducing its incidence primarily.
Factors influencing the probability of conception following artificial insemination with donor semen (AID) have been investigated in a series of 124 married females. Overall, 79 conceptions were achieved, for a cumulative rate of conception of 85.1% at the end of 1 year and an average fecundability of 15%, using life-table analysis. Women aged 30 or over or those with evidence of tubal or ovulatory problems had decreased probability of conception, although not to a significant extent. Women whose husbands were azoospermic had 20% fecundability in response to AID, significantly better than the 10% fecundability after AID observed in the women whose mates were oligospermic. Cycles during which AID was successful were significantly more likely to have had a positive postcoital test observed, compared with unsuccessful AID cycles.
Information on reproductive history was obtained from 362 urban breast cancer patients attending the oncological dispensaries at Tallinn and Tartu, Estonian Republic, and from 694 urban women participating in gynecologic screening programs offered by the same centers. The 2 groups were compared by means of Mantel-Haenszel and logistic regression procedures to estimate age-adjusted odds ratios. Women whose first birth occurred before 20 years of age had a breast cancer risk less than one-third the risk of nulliparous women. Risk increased with increase in age at first birth (AFB) but remained below 1.0 (relative to nulliparae), even in the highest AFB categories. The fertility rate in Estonia during the period of this study was relatively low, which facilitated an evaluation of the effect of births subsequent to the first. After adjustment for AFB, it appeared that in this population subsequent births had a protective effect additional to that conferred by the first birth. Moreover, for women who had only 2 children, the age at the time of birth of the second child was a determinant of that effect. Compared to nulliparous women, the breast cancer odds ratio for uniparous women who had their child before age 25 was 0.62, and the ratio for duoparous women who had both their children under that age was 0.18. Neither lactation nor menarche was a risk factor for breast cancer in this pouplation.
A double-blind crossover study was designed to compare the effects of placebo and medroxyprogesterone acetate, 20 mg, on vasomotor flushes and blood hormones in 27 postmenopausal women. In women receiving placebo, vasomotor flushes were decreased by 25.9% during the last four weeks of treatment compared with baseline, and a further decrease of 34.5% was achieved by the last four weeks after patients were given medroxyprogesterone. In women who initially took medroxyprogesterone, there a 73.9% decline by the last four weeks in the number of vasomotor flushes. However, when these women were given placebo, an immediate worsening of their symptoms occurred. The drug produced a decline of 27% and 29% in serum levels of follicle-stimulating hormone and luteinizing hormone, respectively, while the serum prolactin level rose slightly. Thus, medroxyprogesterone can be used to treat the vasomotor flushes of postmenopausal women when estrogen use is undesirable.
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Population surveys have demonstrated an inverse relationship between breast cancer incidence rates and the urine "estriol ratio," the concentration of estriol relative to the sum of the concentrations of estrone and estradiol. In this study, the urine estriol ratio was evaluated in premenopausal breast cancer patients and control women from Boston and San Francisco. Although at least 2 years had passed since last use of oral contraceptives, women with a history or oral contraceptive use for 19 months or longer excreted estrogen in low concentrations compared to nonusers and so were excluded. Among the remaining 73 cases and 55 controls, the cases had lower estriol ratios and higher estrone and estradiol levels than did controls. However, these differences, which averaged about 10%, were not statistically significant. Thus the hypothesis that a low estriol ratio is a cause of breast cancer is given only minimal support. Among women in their 40's, the excretion of estrogens is subject to many influences and is difficult to study. The many determinants of estrogen excretion, including age and oral contraceptive use, should be accommodated in the design of future studies of the estriol ratio.
The role of diet in the etiology of cancer of the breast and endometrium is considered. Geographic variation in rates, effects of migration, consequences of exogenous hormone use, and other epidemiologic factors are reviewed. Cancer of the endometrium is related to diet probably through simple caloric excess. The excess is reflected in obesity and the consequent overproduction of estrone, a natural but carcinogenic human estrogen. Diet may also influence breast cancer risk somewhat through the same mechanism. But this mechanism probably would not explain a large proportion of the disease. It is possible that, in addition, some specific dietary factor, for example, saturated fat, is causally related to breast cancer. Such a relationship would probably be mediated through an endocrine mechanism.
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There are a number of distinct theoretical approaches to counselling. The most influential are behavioural, cognitive-behavioural, psychodynamic and person-centered treatments. However, the factors responsible for the beneficial effects of treatment remain to be discovered.
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