The increased prevalence and the severity of oropharyngeal candidiasis in human immunodeficiency virus (HIV)-positive patients are attributed exclusively to the virus-induced immune deficiency of the host. The present study was aimed at answering the question of whether Candida albicans secretory proteinase, a putative virulence factor of the opportunistic C. albicans yeast, has any potential influence on the clinical manifestation of oropharyngeal candidiasis in HIV-positive patients. We measured the secretory proteinase activities of clinical C. albicans isolates from the oropharynges of either HIV-positive individuals (n ؍ 100) or a control group (n ؍ 122). The mean secretory proteinase activity of C. albicans isolates from the HIV-positive group (4,255 ؎ 2,372 U/liter) was significantly higher compared with that of isolates from the control group (2,324 ؎ 1,487 U/liter) (P < 0.05). The higher level of secretory proteinase activity in the culture supernatants of individual C. albicans isolates correlated with the increased level of proteinase expression on the cell surface, as revealed by cytofluorometry, and with higher levels of secretion of the immunodetectable protein, as shown by Western blotting (immunoblotting). Proteinase activity within the population of C. albicans isolates from HIV-positive individuals was independent of the patient's clinical disease stage and the CD4 ؉ /CD8 ؉ cell numbers. Furthermore, no correlation of the proteinase activities with the C. albicans serotype was found, although C. albicans serotype B was significantly more frequent in the HIV-positive group (40%) compared with that in the control group (12%). However, a positive correlation of proteinase activity to antifungal susceptibility was evident. The C. albicans isolates from the HIV-positive group that were characterized by higher levels of proteinase activity were also less susceptible to the widely used azole antifungal agents ketoconazole and fluconazole. Collectively, the present data are consistent with a concept of early preferential selection of a subpopulation of C. albicans in HIV-infected patients.
The human mammary carcinomas MT-1 and MT-3 originate from surgical material and were transplanted in nude mice. Both tumors have been classified as estradiol- and progesterone receptor-negative. Therapeutic doses of hormones and anti-hormones remained without growth inhibitory effect. MT-1 and MT-3 proved to be sensitive to conventional cytostatic drugs used for treatment of mammary carcinomas; striking is their sensitivity to ether lipids. Therefore, they are considered suitable tumor models for this class of substances.
FOLLOWING the basic investigations of Huggins, Grand and Brillantes (1961), Huggins, Briziarelli and Sutton (1959) and Dao (1964) it is readily possible to induce mammary cancers in female Sprague-Dawley rats by administration of 3-methylcholanthrene or 7,12-dimethylbenzanthracene (DMBA), thus allowing the behaviour of these tumours to be studied under various conditions. As has been established particularly by Huggins, Grand andBrillantes (1961), and Furth (1961), the growth of these tumours depends on hormone state in the organism of the experimental animals, and may be reduced by male hormones (testosterone) or stimulated by female hormones (oestrogens, progesterone). Dao (1964) showed that mammary cancers can also be induced in rats by oestrogens alone so that a carcinogenic effect of female hormones cannot be excluded.The application of carcinogenic hydrocarbons mentioned is very frequently accompanied by acute toxic phenomena and leads in many cases to the death of the animals. Only when quite definite dose-time-relationships are noticed will these toxic effects be minimized. The purpose of our own studies was to check the possible existence of dose-effect-relations for testosterone in influencing the growth of DMBA-induced mammary cancer in rats by this androgen. The development of tumours following DMBA treatment has been noted and the growth rates of tumours which formed at different times have been compared with one another. MATERIAL AND METHODSFemale Sprague-Dawley rats aged 51 to 58 days were used. The animals were fed with a standard biscuit diet according to Kiissner (Heise and Gorlich, 1964) and water given ad libitum. The mammary cancers were induced by three gastric intubations of 10 mg. of DMBA in 1 ml. of sunflower oil at intervals of 7 days (Engelhart and Gericke, 1964). All DMBA treated animals were examined three times a week for tumours. The time interval between the first DMBA application and the moment the tumours become palpable will be referred to as the induction time. The growth of the individual tumours was checked by measuring two diameters three times a week. These diameters were multiplied by each other and the value obtained was plotted against time. For therapy some of the animals were injected with varying testosterone dosages which are listed in Table IV. The testosterone preparation was an oily solution of testosterone propionate (VEB Jenapharm), which was injected intramuscularly.
The existence and the concentration of the estradiol receptor (ER) in breast cancers of pre- and postmenopausal patients were measured. ER status and concentration are significantly higher in cancers of postmenopausal women. Breast cancers operated at various phases of the menstrual cycle showed remarkable differences in ER incidence and concentration. The highest values were found in the early proliferative phase, whereas the ER incidence is lowest in cancers which were operated at early secretory phase. ER concentrations found in late proliferative and late secretory phases are significantly lower than those found in cancers of postmenopausal patients. Statistically significant differences of the ER concentrations between the various phases of the menstrual cycle could not be secured.
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