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Changes in plasma concentrations of sex steroids were examined in male and female zebra finch chicks during the sensitive period for differentiation of sexually dimorphic brain nuclei associated with the control of song. Using a chromatographic separation procedure and radioimmunoassay, androstenedione, testosterone and 5 alpha-dihydrotestosterone were detected in plasma at relatively high concentrations immediately after hatching. There were no sex differences in concentrations of these androgens. An oestrogen, oestradiol-17 beta, which is known to differentiate the song-control system, is raised specifically in the circulating plasma of male zebra finch chicks, and not in females. The surge in oestradiol, which occurs during the first week after hatching, coincides with the period when capacity for differentiation of the song system is maximal. Exposure of the male brain to oestradiol-17 beta could trigger neuronal differentiation.

The effects of testosterone (T) treatment on androgen-metabolizing enzymes and especially on aromatase were examined in the developing hypothalamus of quail using an in vitro microassay. Testosterone propionate (TP) injected into the pectoral muscles of one-day-old chicks had no effect on formation of 5 alpha-dihydrotestosterone (5 alpha-DHT), 5 beta-dihydrotestosterone (5 beta-DHT) and 5 beta-androstane-3 alpha, 17 beta-diol (5 beta,3 alpha-diol) in the hypothalamus. By contrast, aromatase activity was significantly enhanced in the anterior (PA) and in the posterior (HT) parts of the hypothalamus of these chicks 18-23 h after a single injection of TP. This increase was site specific as it did not occur in control non-target areas, neostriatum intermediale and hyperstriatum ventrale (VN). The increase in hypothalamic aromatase activity was accompanied by T-dependent changes in behavior and somatic development. Although aromatase activity is present as early as day 10 of embryonic life in PA and HT, it becomes inducible by circulating T only after this stage of development. There is also an important increase in basal aromatase activity during embryonic development. At day 10, when the brain is particularly sensitive to the differentiating effects of gonadal steroids, formation of 5 alpha-DHT and 5 beta-DHT in the hypothalamus is higher in females than in males. We conclude that although all important pathways of T are already present on day 10 of embryonic life, the brain metabolism of androgens continues maturing during the whole embryonic life.

The presence of pre-existing hemostatic disorders in a surgical patient may pose difficulties in the care of patients during and after surgery. To reduce the risk of excessive hemorrhage, this article has stressed the value of a thorough medical history, physical examination, and appropriate laboratory assays before surgery. When these measures reveal no evidence of a coagulation disorder, the surgeon can have confidence that the patient's hemostatic system has the appropriate resources to prevent excessive bleeding during surgery. However, if the coagulation screening procedure suggests that an abnormality exists, specific diagnostic assays must be performed before any necessary surgery to determine the exact nature of the coagulopathy. When this information is present, specific forms of blood component therapy can be given to minimize the risk of excessive hemorrhage during the operative period.

This study investigated whether gonadal hormones are required for sexual imprinting in male Japanese quail during the period of exposure to the imprinting stimulus. Brown males were either castrated or laparotomized on the day of hatching. Between Days 10 and 30 of age castrated males (N = 15) and intact laparotomized males (N = 10) were exposed individually to white females. A 2nd group of intact laparotomized males (N = 13) were exposed to brown females. When adult (Day 54), 7 of the castrated males were treated with testosterone propionate (TP): the remaining 8 castrated males and intact groups received saline. All males were given choices between novel white and novel brown females starting on Day 62. The TP-treated castrated males behaved like intact white-exposed males, preferring to approach and copulate with white females significantly more readily than did intact brown-exposed males. The untreated castrated males showed no sexual behavior. The results indicate that gonadal hormones are not required during the period of exposure to an imprinting stimulus in male Japanese quail.

This study compared T-cell colony formation in soft agar of lymphocytes from the peripheral blood and lymph nodes of patients with non-Hodgkin's lymphoma (NHL) with T-cell colony formation of peripheral blood lymphocytes from normal individuals. Mononuclear cells were separated from other blood and lymph node elements on density gradient columns, phenotyped for T- and B-cell antigens using monoclonal antibodies, and then plated in soft agar cultures. Lymphocytes from peripheral blood and lymph nodes of patients with NHL exhibited less T-cell colony formation (p less than 0.01) than did lymphocytes from normal individuals. This decrease in T-cell colony formation was not the result of the number of T cells or null cells plated, or differences in proportions of T helper and T suppressor cells. However, when sera from patients with NHL were incubated with normal lymphocytes before plating in soft agar, a decrease in number of T-cell colonies was observed (p less than 0.01). We conclude that peripheral blood and lymph node mononuclear cells from patients with NHL have a decreased ability to form T-cell colonies in soft agar cultures and that this decrease is related, at least in part, to the presence of serum factor(s).

This study examines the effects of nonaromatizable androgens, methyltrienolone (R1881) and 5 alpha-dihydrotestosterone (DHT) on aggressive courtship and vocal behavior in the male ring dove. Since androgens may influence behavior by increasing the formation of estrogen in the brain, the effects of R1881 and DHT on brain aromatase activity were also studied using an in vitro microassay. Under conditions in which testosterone induced aggressive courtship patterns, the nonaromatizable androgens were ineffective. But DHT and R1881 induced vocal behavior with equal efficiency, indicating that androgens can influence mechanisms of vocal behavior without conversion to estrogens. The behavioral effectiveness of both hormones was reduced (approximately 50%) when the period between castration and treatment was doubled. Testosterone propionate increased formation of E2 from 3H-testosterone in both the preoptic (POA) and anterior hypothalamic areas. Neither of the nonaromatizable androgens affected POA aromatase activity. The results suggest that only the aromatizable androgen, testosterone, which is also required specifically for male courtship, increases preoptic formation of estrogen.

Bone sarcomas are the most common second malignant neoplasms in survivors of a malignant solid tumor in childhood. In contrast to de novo tumors, secondary bone cancers are typically associated with a poor prognosis, reflecting both a preponderance of primary sites that preclude complete resection in the flat bones of the axial skeleton, and the tendency for local invasiveness or distant metastasis. We describe a patient who developed malignant extradural osteosarcoma of the temporal bone 6 years after successful treatment for a malignant cerebellar astrocytoma with surgical resection and local irradiation. A complete resection of the sarcoma was not possible; however, she achieved a biopsy-proven complete response after intensive chemotherapy with ifosfamide, followed by cisplatin and doxorubicin. At age 13, she remains free of recurrence 3 years after completing all therapy. In view of the rarity of prolonged disease control after incomplete resection for osteosarcoma, this report suggests the value of intensive combination chemotherapy in achieving a durable unmaintained remission in our patient.

Intact, breeding female budgerigars enter and occupy a nestbox 8-10 days before egg-laying. Ovariectomized budgerigars did not enter nestboxes. Oestradiol-17 beta monobenzoate (OB) (0-05 mg, i.m.) induced ovariectomized birds to enter nestboxes. Higher dosages (0-1 or 0-5 mg) did not facilitate this effect. The amount of time spent in nesting behaviour by all OB-treated groups did not differ from that shown by a group of intact females during the initial phase of the nesting sequence (first 4 days in the nestbox), but was significantly less than that of intact females undergoing later stages of nesting behaviour (4 days before and after laying the first egg). Oestradiol induced a increase in oviduct weight and size which was dose-dependent. With a low dose (0-05 mg OB), the oviducts were slightly larger than those of intact females which had been in the nestbox 1-2 days. With higher dose levels (0-1-0-5 mg OB), precursor albumen granules had formed in tubular glands of the magnum, a stage more typical of females which had been in the nestbox 4-6 days. The results indicate that low levels of oestrogen induce female budgerigars to enter nestboxes and initiate oviduct development. Subsequent phases of the nesting behaviour and oviduct development may be causally related to other hormones.