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ALTHOUGH a significant role has been established for oestrogen in the growth of some animal1,2 and human3,4 mammary carcinoma, evidence for androgen dependency of human breast cancer has remained equivocal. Although the existence of a mouse mammary carcinoma which shows modest androgen responsiveness5 has supported the notion that some human breast cancer might also be dependent on androgens, no direct proof has been available. We have described our work characterising the oestrogen responsiveness of MCF-7, a human breast cancer cell line maintained in tissue culture for over 3 yr (ref. 6). This cell line was shown to contain oestrogen receptor, to be killed by antioestrogens, and stimulated by physiological concentrations of oestradiol. We now describe further investigations of this cell line which reveal that in addition to oestrogen responsiveness, this cell line shows threefold enhancement of precursor incorporation into macromolecules by androgens using serum-free conditions which preclude stimulatory effects of other trophic hormones. Furthermore, this stimulation by androgens seems to be mediated by interaction with a cytoplasmic androgen receptor protein which is clearly differentiable from the oestrogen receptor also found in these cells. Aside from defining an interesting new system in which the action of androgen can be studied in a human cell line in tissue culture, the present study provides unequivocal evidence for the androgen responsiveness of some human breast cancer at least in vitro.

A diphasic medium, Trans-Isolate medium, was developed for the transport of primary cultures of cerebrospinal fluids from patients with bacterial meningitis. It consists of a charcoal-starch agar slant and soybean-casein digest-gelatin broth buffered at pH 7.2 with 0.1 M 3-(N-morpholino)propanesulfonic acid buffer. In the laboratory, this medium supported the growth and survival of stock cultures of Neisseria meningitidis, Streptococcus pneumoniae, and Haemophilus influenzae for at least 3 months. Under field conditions in Africa, cerebrospinal fluids from patients suspected of having bacterial meningitis were inoculated directly onto plates of chocolate agar medium and into bottles of Trans-Isolate medium. An etiological agent was isolated from 52 spinal fluids by direct plating. After shipment to Atlanta, Ga., 2 to 4 weeks later, the same etiological agents were recovered from 38 bottles of Trans-Isolate medium.

The mechanisms of steroid and peptide hormone action in human breast cancer are poorly understood. We have previously characterized a cell line of human breast cancer in long-term tissue culture that possesses various steroid hormone receptors and responses, providing a model for the study of steroid hormone action. The present studies describe a human breast cancer in vitro that responds to physiologie concentrations of insulin with an increased rate of macromolecular synthesis and growth. Thymidine and uridine incorporation in cells in serum-free medium are stimulated by 10(-11) M insulin and are maximal with 10(-8) M. Leucine incorporation is stimulated by 5 X 10(-11) M insulin and is maximal with 10(-9) M. Significant stimulation of uridine and leucine incorporation is evident by 3 hr and maximal by 10 hr. A 10-hr lag period exists for insulin stimulation of thymidine incorporation, which is maximal form 14 to 24 hr. The effect of 10(-8) M insulin on macromolecular synthesis is accompanied by a 69% increase above controls in the number of cells after 24 hr. The effect on macromolecular synthesis is observed in glucose-free medium. Insulin's effect on protein synthesis is not blocked by inhibition of RNA synthesis with actinomycin D. Glucocorticoids partially inhibit the action of insulin in these cells. This system provides a model for studying insulin action, and suggests that some human breast cancer may show growth regulation by insulin.

Methods of collecting endocervical samples for the detection of Chlamydia trachomatis were evaluated. We compared Calgiswab and cytobrush for isolation in cell culture and Dacron swab and cytobrush for direct fluorescent-antibody (DFA) testing for 632 females attending a sexually transmitted disease clinic. An additional specimen for enzyme immunoassay (EIA) was also collected. True-positives were identified as tissue culture positive and/or both DFA and EIA positive. Use of the cytobrush significantly improved the sensitivity of both the culture (69% with swab and 100% with cytobrush) and DFA testing (68% with swab and 85% with cytobrush). The EIA sensitivity was 85%. The specificity of each test was greater than or equal to 98%. The cytobrush appears to be the superior method for the collection of cervical samples from nonpregnant women.

A meningitis outbreak due to Neisseria meningitidis, serogroup C, serotype 2b, occurred in central Vermont in February, 1984. The highest incidence was in Northfield, where 7 cases occurred (129 per 100,000 population). Of these 7 cases 2 were students at Northfield High School and 5 were younger children; all had had close contact with Northfield High School students or staff in the week before illness. A case-control study demonstrated that these cases had significantly more exposure to Northfield High School students or staff in the 2 weeks before illness (112 hours) than did controls (8 hours) (P = 0.006). This finding was confirmed by a second case-control study designed to determine risk factors for the entire outbreak. School children in Northfield and their household contacts were given meningococcal A-C vaccine and sulfisoxazole prophylaxis. No further cases of meningococcal disease occurred in Northfield after the week that these control methods were initiated. Transmission of the outbreak strain of N. meningitidis appears to have occurred in a school setting with subsequent illness in household and close contacts of carriers of the outbreak strain.

Physiologic concentrations of estrogen stimulate precursor incorporation and growth in several lines of human breast cancer cells in long term tissue culture. Antiestrogens inhibit precursor incorporation and eventually kill the cells. Estrogens reverse antiestrogen effects. Responsive cell lines contain high affinity specific cytoplasmic receptors for estrogen. When binding and stimulation are measured under similar conditions, it appears that only a small proportion of receptor sites need be occupied for maximal stimulation. Thymidine kinase specific activity is increased by estradiol and may, in part, explain enhanced thymidine incorporation. These cell lines should prove useful for the study of the mechanisms by which estrogens regulate growth in human breast cancer

Background: Herpes simplex virus type 2 (HSV-2) is one of the most common sexually transmitted infections and may enhance transmission of HIV. However, population-based estimates of HSV-2 prevalence and correlates of infection are rare. Goals: To obtain population-based estimates of HSV-2 prevalence and to identify demographic and sexual behavioral correlates of infection among women in low-income communities of Northern California. Study Design: A randomized, single-stage, cluster sample, cross-sectional survey of women age 18 to 29 years who reside in 1990 US Census block groups at the lowest tenth percentile for household income. Results: The survey-weighted prevalence of HSV-2 infection was 34.8% (95% CI, 30.4-39.2). Factors independently associated with HSV-2 seropositivity were black race, older age, lower income, parity, greater number of lifetime male sexual partners, earlier onset of sexual intercourse, sex work, history of sexually transmitted disease (STD), and cocaine use. Conclusion: The high prevalence of HSV-2 and the strong correlation with sexual risk underscores the potential for further spread of STD, including HIV, in this young population.

The efficacy of pneumococcal vaccine in groups of patients in the United States at high risk for pneumococcal disease was estimated by comparing distributions of serotypes of Streptococcus pneumoniae isolated from vaccinated and unvaccinated persons. Between May 1978 and March 1984, 187 blood isolates and 62 cerebrospinal fluid isolates from vaccinated patients, and 1447 blood isolates and 191 cerebrospinal fluid isolates from unvaccinated patients were serotyped at the Centers for Disease Control. The study did not include patients who were less than 2 years old or who had Hodgkin's disease, multiple myeloma, or immunoglobulin deficiency. In patients with bacteremic disease, the overall efficacy of pneumococcal vaccine was estimated at 64% (95% confidence limits, 47% to 76%); efficacy did not differ significantly with age. In persons over 65 years of age with diabetes mellitus, chronic heart disease, pulmonary disease, or no underlying illnesses, efficacy was 61% (95% confidence limits, 1% to 85%). These findings support the use of pneumococcal vaccine in selected populations in the United States.