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1.
The estrogen component in oral contraceptives is generally thought to increase the risk of stroke in users as compared with controls. If this were true, an increased risk for stroke also should be seen among postmenopausal women using estrogens as compared with nonusers. To test this hypothesis, the charts of 198 postmenopausal patients who had had strokes were compared with those of 396 controls for estrogen use and for the associated risk factors of diabetes, hypertension and coronary artery disease. The difference between estrogen use in the study population versus controls proved not significant, and the use of estrogens did not significantly influence the distribution of the above risk factors. We concluded that the use of estrogens in physiological replacement doses does not increase the risk of stroke in postmenopausal women.  相似文献   

2.
From experience in six cases the anabolic steroid hormones, especially long-acting testosterone and estrogen preparations, are the treatment of choice in Paget''s disease, as in postmenopausal osteoporosis. Details of the management of three patients over a period of four years are presented.Roughly 4 per cent of the population, mostly persons over 40, show some evidence of Paget''s disease. Only a small number of them, however, have severe manifestations requiring treatment, such as pain, howing or fracture of the bones, pressure on nerves or heart failure. In rare cases malignant changes occur in the involved bone.Since the cause of Paget''s disease is not known, treatment in the past has been largely empirical. Reifenstein and Albright had advocated the therapeutic use of calcium, vitamin D and ascorbic acid, and, in postmenopausal women, administration of estrogens; but with fractures or immobilization, intake of calcium-containing foods, such as milk, must be restricted to avoid dangerous piling up of calcium and kidney stones, and fluids must be forced. In recent years anabolic steroid hormones, principally oral androgens and estrogens, have been employed by Gordan and others to promote bone repair, lessen bone pain and decrease urinary excretion of calcium. While these hormones probably do not arrest the disease, they seem to stabilize it and bring relief of symptoms.More recently, Albright and Henneman demonstrated that very large doses of corticotropin (ACTH) or cortisone resulted in immediate cessation of bone pain, decrease in urinary excretion of calcium and histologic evidence of regression of the disease process. The large doses required, however, also produce dangerous side effects, such as psychosis and osteoporosis, indicating that such treatment probably should not be continued over long periods.  相似文献   

3.
Estrogens are reported to reduce the incidence of Alzheimer's disease and 17β-estradiol (βE2), the potent, naturally occurring estrogen, exerts neuroprotective effects in a variety of in vivo and in vitro model systems. The present study elucidates the structural requirements of steroids and related compounds for neuroprotectivity at low nM doses. All estrogens tested with an intact phenolic A ring protected SK---N---SH neuroblastoma cells from the toxic effects of serum-deprivation. All 3-O-methyl ether cogeners tested were inactive indicating the importance of a phenolic A ring. The diphenolic estrogen mimic diethylstilbesterol (DES) was neuroprotective and retention of a single phenolic function was sufficient to retain neuroprotective activity. The di-O-methyl ether of DES was inactive. The following steroids which lack a phenolic A ring were also inactive: testosterone; dihydrotestosterone; progesterone; corticosterone; prednisolone; 6 -methylprednisolone; aldosterone; and cholesterol. Finally, phenol, lipophilic phenols, and tetrahydronapthol were inactive. These results suggest that a phenolic A ring and at least three rings of the steroid nucleus are necessary for the neuroprotective activity of estrogens.  相似文献   

4.
Propranolol blood levels and the effect of these levels on hemodynamic parameters were evaluated in 25 patients with coronary artery disease undergoing cardiac catheterization and coronary angiography. Fifteen patients were receiving high doses of propranolol (320--1920 mg/day) while ten patients were receiving conventional doses (80--240 mg/day). The high dose propranolol group had significantly higher plasma propranolol levels than the conventional dose group (788 +/- 134 SD vs. 43 +/- 7.2 ng/ml SD), and there was a direct linear relationship between propranolol dose and plasma drug levels (r = 0.85, P < 0.001). There were no significant differences between high and conventional dose propranolol groups in terms of all hemodynamic parameters measured, namely ejection fraction, ventricular volume, cardiac index, or peripheral vascular resistance. Despite high drug dosage and blood levels, only mild side effects were seen.  相似文献   

5.
Exemestane experience in breast cancer treatment   总被引:2,自引:0,他引:2  
Exemestane is a very potent, orally active, selective and long-lasting steroidal irreversible inhibitor of aromatase. It is 150 times more potent than aminoglutethimide (AG) in inhibiting human placental aromatase (Ki of 4.3 and 671 nM, respectively). The compound is presently under phase III evaluation in Europe and the U.S.A. for the treatment of postmenopausal advanced breast cancer (ABC). Clinical pharmacology studies have been carried out with single doses ranging from 0.5 to 800 mg and repeated doses of up to 600 mg a day, in 132 postmenopausal healthy volunteers and in 185 post-menopausal women with ABC. Results obtained using a very specific and sensitive analytical method (high performance liquid chromatography—radioimmunoassay; HPLC—RIA) indicated that exemestane is extremely effective in inhibiting plasma estrogens levels. Estrogen inhibition is clearly evident at 5 mg a day and maximal suppression for E2, E1 and E1S (>85%, >90% and>90%, respectively) is obtained at 10–25 mg a day. Data from non-controlled phase II studies involving more than 400 patients indicated a clear anti-tumour activity in postmenopausal ABC patients failing multiple hormonal treatments. In 62 patients progressing on AG (≥500 mg a day) exemestane treatment resulted in an objective response rate of approximately 24%; disease stabilization ≥24 weeks was observed in an additional 24% of cases. With regard to safety, although daily doses up to 600 mg were administered, the maximal tolerated dose was not achieved; reported symptoms were mainly related to the pharmacological action of the compound and were usually mild to moderate in severity, resulting in the discontinuation of therapy in less than 3% of cases. In conclusion, the available results suggest that exemestane treatment is associated with minimal toxicity, and may be of significant benefit for ABC women who have exhausted conventional therapy.  相似文献   

6.
Although serum testosterone levels decrease acutely in critically ill patients, estrogen levels rise. We hypothesized that increased rates of aromatization of androgens to estrogens underlie the increase in serum estrogen levels. Eleven men and three women (age 42-69 yr) were prospectively studied before and again after elective coronary artery bypass graft surgery (CABG). Each patient received priming doses of [(14)C]androgen and [(3)H]estrogen that were immediately followed by peripheral infusions for 210 min. Eight men and three women received androstenedione (A(4))/estrone (E(1)) and three men received testosterone (T)/estradiol (E(2)). Adipose tissue biopsies were obtained in another six men before and after CABG to evaluate levels of P450 aromatase mRNA. Serum T levels decreased postoperatively in all 17 men (P < 0.001), whereas E(1) levels rose (P = 0.004), with a trend toward a rise in E(2) (P = 0.23). Peripheral aromatization rates of androgens to estrogens rose markedly in all 14 patients (P < 0.0001). Estrogen clearance rates rose (P < 0.002). Mean serum A(4) levels increased slightly postoperatively (P = 0.04), although no increase in A(4) production rates (PRs) was observed. T PRs decreased in two of three men, whereas clearance rates increased in all three. Adipose tissue P450 aromatase mRNA content increased postoperatively (P < 0.001). We conclude that the primary cause of increased estrogen levels in acute illness is increased aromatase P450 gene expression, resulting in enhanced aromatization of androgens to estrogens, a previously undescribed endocrine response to acute illness. Both increased T clearance and decreased T production contribute to decreased serum T levels. Animal studies suggest that these opposing changes in circulating estrogen and androgen levels may be important to reduce morbidity and mortality in critical illness.  相似文献   

7.
Nineteen patients with Cushing''s disease were treated with low dose external pituitary irradiation (20 Gy (2000 rad) in eight fractions over 10 days). While awaiting the effects of pituitary irradiation all patients were treated with metyrapone. Seven patients had a complete remission of their disease within six to 12 months of irradiation. They did not require any further treatment and were followed up for a mean of three and a half (range one to eight) years. Another patient had a complete remission after a second course of pituitary irradiation. A further two patients showed a significant biochemical improvement after irradiation, although they were not rendered eucorticoid. There were no complications after this dose of irradiation. These results compare favourably with those reported after pituitary irradiation at conventional doses (40-50 Gy (4000-5000 rad) over four or five weeks) but were not associated with any complications. It is therefore recommended that low dose external pituitary irradiation be used as definitive first line treatment for Cushing''s disease.  相似文献   

8.
9.
The primary objective of this study was measurement of the systemic bioavailability of DHEA and its metabolites following daily intravaginal application of the sex steroid precursor. Forty postmenopausal women were randomized to receive a daily dose of one ovule of the following DHEA concentrations: 0.0%, 0.5%, 1.0% or 1.8%. After only 7 days of treatment, the maturation value of the vaginal epithelial cells was significantly increased while the vaginal pH was significantly decreased at all DHEA doses. These important local effects were observed while the serum concentrations of estradiol and testosterone remained within the values found in normal postmenopausal women at all DHEA doses. Similar observations were made for serum androstenedione, estrone, estrone-sulfate and DHEA-sulfate. Even at the highest 1.8% DHEA dose, serum DHEA was increased at the levels found in normal premenopausal women. The present data show that the intravaginal administration of DHEA permits to rapidly achieve the local beneficial effects against vaginal atrophy without significant changes in serum estrogens, thus avoiding the increased risk of breast cancer associated with the current intravaginal or systemic estrogenic formulations. In addition, the recent observation that DHEA is transformed into both androgens and estrogens in the vagina permits to exert benefits on all the three layers of the vaginal wall.  相似文献   

10.
Bleomycin alone was used in the treatment of 54 patients with Hodgkin''s disease in its later stages, 17 with generalized lymphosarcoma, 22 with reticulum cell sarcoma, and 7 with mycosis fungoides. The patients had had radiotherapy and full courses of conventional chemotherapy. Bleomycin was given in doses of 30 mg weekly to an average total dosage of 200 mg, though up to 800 mg could be given because of its marrow-sparing properties. Sixteen (29%) of the patients with Hodgkin''s disease remitted, most of them achieving only a partial remission, and similar results were obtained in the other three reticuloses. Bleomycin would seem to have some beneficial action in the late stages of Hodgkin''s disease, though it is less effective than some drug regimens recently introduced. Nevertheless it may be useful when there is diminished bone marrow reserve. It would be a suitable drug to use in combination therapy of these four reticuloses.  相似文献   

11.
In this paper, a methodology for the determination of three naturally occurring estrogens (estradiol, estrone and estriol) in pregnant women's urine has been described. The procedure included immunoaffinity column (IAC) extraction of 4 mL of urine sample and subsequent analysis of the extraction by micellar electrokinetic chromatography (MEKC). A multi-target polyclonal antibody that has high affinity to three estrogens was produced. Then the IAC was developed by coupling polyclonal antibody to CNBr-activated Sepharose 4B. The IAC showed high affinity for these estrogens. Recoveries of three estrogens from human serum matrix were greater than 92% with R.S.D. less than 4.5%. The final elute of urine sample was diluted with running buffer and then quantitated with MEKC. The experimental results demonstrated that IAC was a useful technique for extraction and concentration of estrogens from biological samples. Three estrogens levels in six pregnant women's urine were measured by both the present method and enzyme-linked immunoadsorbent assay (ELISA). The results of this method have been found to correlate well with those of ELISA.  相似文献   

12.
The majority of data regarding biological effects of estrogens is based on studies in male rats or ovariectomized (Ovx) female rats. Therefore, in this study, the effects of estradiol treatment on the regulation of the hepatic estrogen receptor and the level of circulating angiotensinogen were examined in the intact female rat. The data were compared with that of the hypophysectomized (Hx) rat. Animals were treated with either low (physiological) or high (pharmacological) doses of estrogen. In intact rats, the hepatic estrogen receptor (ER) level increased with increasing doses of estrogen. This was in contrast to the Hx rats where growth hormone (GH) and dexametasone (Dex) in combination were the sole modulators of the estrogen receptor. The angiotensinogen level increased in normal rats after estrogen administration in a dose dependent manner, regardless of the mode of administration. The pure antiestrogen ICI 182 780 efficiently blocked the increase in circulating angiotensinogen. The conclusion is that in the normal female, estrogens are important modulators of the serum angiotensinogen level.  相似文献   

13.
Estrogen suppression is an effective endocrine treatment option in pre- as well as postmenopausal breast cancer patients. The fact that it produces clinical benefits not only in these two groups of patients that differ significantly with respect to plasma estrogen levels but also among patients with very low plasma estrogen levels due to previous hypophysectomy, adrenalectomy or treatment with first/second generation aromatase inhibitors, suggests estrogen deprivation to work independent of pretreatment plasma estrogen levels. Interestingly, in vitro studies have revealed MCF-7 cells to respond to estrogen deprivation by sensitization, causing maximum estradiol stimulation at a concentration 10−5 to 10−4 the concentration needed in wild-type cells. While results from recent phase III studies comparing novel aromatase inhibitors and inactivators to conventional therapy have suggested that a more effective hormone ablation may be translated into an improved clinical efficacy, the biochemical rationale for lack of complete cross-resistance between aromatase inhibitors and inactivators or aromatase inhibitors and megestrol acetate remains to be explained. Interestingly, patients becoming resistant to estrogen deprivation may still respond to estrogens administered in pharmacological doses. Future studies are warranted to explore alterations in gene expression and signaling mechanisms in response to different therapies in tumor tissue in vivo.  相似文献   

14.
A glutaminase-asparaginase enzyme from Achromobacter sp has antitumour activity in vitro and in animals. Glutaminase was administered in doses of 3500-20 000 IU/m2 body surface area/day to six patients with acute lymphoblastic leukaemia (ALL) and three patients with acute myeloid leukaemia (AML). The enzyme had a blood half life of 80 minutes but depletion of blood glutamine persisted for 12 hours after single doses. Seven patients, including four (two with AML and two with ALL) resistant to asparaginase, received repeated doses of glutaminase. Antileukaemic effects were observed in all seven; one elderly patient developed metabolic acidosis. Study of this new antileukaemic agent in patients with acute leukaemia at an earlier stage of their disease is now justified.  相似文献   

15.
Aromatase inhibitors and their application in breast cancer treatment*   总被引:2,自引:0,他引:2  
Brodie AM  Njar VC 《Steroids》2000,65(4):171-179
Estrogens are known to be important in the growth of breast cancers in both pre- and postmenopausal women. The number of breast cancer patients with hormone-dependent disease increases with age, as does the incidence of breast cancer. Although estrogens are no longer made in the ovaries after menopause, peripheral tissues produce sufficient concentrations to stimulate tumor growth. Because aromatase catalyzes the rate-limiting step in the biosynthesis of estrogen, inhibitors of this enzyme have been developed in the last few years as a logical treatment strategy. Two classes of aromatase inhibitors, steroidal and nonsteroidal compounds, are now in use. Among the steroid substrate analogs, formestane and examestane have been shown to be effective in breast cancer patients with advanced disease. Highly potent and selective nonsteroidal inhibitors have recently been found to suppress plasma and urinary estrogens by more than 95% in breast cancer patients. Two of these compounds recently were approved in the United States and have been shown to be more effective than other second-line agents in terms of overall response rates and treatment failure, as well as better tolerated. Although studies of the efficacy of these agents in earlier stage disease are awaited, it is evident that aromatase inhibitors can extend the duration of treatment in breast cancer patients.  相似文献   

16.
Aromatase inhibitors and hormone-dependent cancers   总被引:1,自引:0,他引:1  
Aromatase (estrogen synthetase) occurs in a variety of tissues. Using immunocytochemistry, we have recently located this enzyme in cellular compartments of several types of human tissue. Furthermore, we found the mRNA was located in the same structures where tested. As both gonadal and peripherally formed estrogen contribute to growth of hormone sensitive cancers, we have developed aromatase inhibitors to block synthesis of this hormone. We have determined that 4-hydroxyandrostenedione (4-OHA) selectively inhibits aromatase activity in ovarian and peripheral tissues and reduces plasma estrogen levels in rat and non-human primate species. 4-OHA was also found to inhibit gonadotropin levels and reduce estrogen and progesterone receptor levels in treated animals. The mechanism of these effects appear to be associated with the weak androgenic activity of the compound. These effects together with aromatase inhibition may result in a synergistic response reducing estrogen production and action. In postmenopausal women, estrogens are mainly of peripheral origin. When postmenopausal breast cancer patients were administered either daily oral or parenteral weekly treatment with 4-OHA at doses that did not affect their gonadotropin levels, plasma estrogen concentrations were significantly reduced. Complete or partial response to treatment occurred in 34% of 100 patients with advanced breast cancer, while the disease was stabilized in 12%. These results indicate that 4-OHA is of benefit in postmenopausal patients with advanced disease who have relapsed from prior hormonal therapies, and that steroidal inhibitors may be of value in premenopausal patients.  相似文献   

17.
Although ovaries serve as the primary source of estrogen for pre-menopausal women, after menopause estrogen biosynthesis from circulating precursors occurs in peripheral tissues by the action of several enzymes, 17beta-hydroxysteroid dehydrogenase 1 (17beta-HSD1), aromatase and estrogen sulfatase. In the breast, both normal and tumoral tissues have been shown to be capable of synthesizing estrogens, and this local estrogen production can be implicated in the development of breast tumors. In these tissues, estradiol (E(2)) can be synthesized by three pathways: (1) estrone sulfatase transforms estrogen sulfates into bioactive estrogens, (2) 17beta-HSD1 converts estrone (E(1)) into E(2), (3) aromatase which converts androgens into estrogens is also present and contributes to the in situ synthesis of active estrogens but to a far lesser extent than estrone sulfatase. Quantitative assessment of E(2) formation in human breast tumors indicates that metabolism of estrone sulfate (E(1)S) via the sulfatase pathway produces 100-500 times more E(2) than androgen aromatization. Breast tissue also possesses the estrogen sulfotransferase involved in the conversion of estrogens into their sulfates that are biologically inactive. In the present review, we summarized the action of the 19-nor-progestin nomegestrol acetate (NOMAC) on the sulfatase, 17beta-HSD1 and sulfotransferase activities in the hormone-dependent MCF-7 and T47-D human breast cancer cell lines. Using physiological doses of substrates NOMAC blocks very significantly the conversion of E(1)S to E(2). It inhibits the transformation of E(1) to E(2). NOMAC has a stimulatory effect on sulfotransferase activity in both cell lines, with a strong stimulating effect at low doses but only a weak effect at high concentrations. The effects on the three enzymes are always stronger in the progesterone-receptor rich T47-D cell line as compared with the MCF-7 cell line. Besides, no effect is found for NOMAC on the transformation of androstenedione to E(1) in the aromatase-rich choriocarcinoma cell line JEG-3. In conclusion, the inhibitory effect provoked by NOMAC on the enzymes involved in the biosynthesis of E(2) (sulfatase and 17HSD pathways) in estrogen-dependent breast cancer, as well as the stimulatory effect on the formation of the inactive E(1)S, can open attractive perspectives for future clinical trials.  相似文献   

18.
Therapeutic doses of [131I]metaiodobenzylguanidine (131I-MIBG) were administered to 5 patients, 3 men and 2 women aged from 33 to 66 years, with proven medullary thyroid carcinoma (one "intermediate" papillary/medullary tumor). The treatment procedure consisted of single doses (3.7-8.5 GBq) of 131I-MIBG given by slow i.v. infusion at 2-8 month intervals. In two advanced-stage patients the treatment played an important palliative role, ranging from an objective response (substantial, but not complete, regression of the tumor) to pain relief which was significant for these patients. In three other cases with residual/recurrent tumor, 131I-MIBG complemented conventional treatment in the attempt to effect a cure which actually was achieved in one case. The only side-effect observed was a transient, mild hematologic toxicity in some cases.  相似文献   

19.
Estrogens along with progesterone/progestins, and other hormones, are important determinants of cancer in the breast, endometrium and ovary. Estrogens may increase the risk of breast cancer through various mechanisms and at various phases of life, with a possible synergistic effect of progesterone/progestins. Exposure to high doses of placental hormones, such as estrogens and/or progesterone, during pregnancy may play a pivotal role in reducing subsequent breast cancer susceptibility. Estrogens cause endometrial cancer, an effect that can be reduced, prevented or reversed by progesterone/progestin — if allowed to act for a sufficiently long period of each cycle. The role of sex hormones seems important for ovarian carcinogenesis. Intake of combined oral contraceptives has a substantial and well-documented protective effect on endometrial and ovarian cancer risks. Epidemiological observations and experimental data from an animal model indicate that estrogens may have an adverse effect, while progesterone/progestins have a risk reducing effect directly on the ovarian epithelium. Thus, estrogens and other sex hormones have potential effects on the three most important female cancers. Research has yet to define how some of the risk factors can be modified or treatment regimens can be improved to reduce these cancer risks.  相似文献   

20.
We report three cases of patients with Parkinson's disease without dementia, admitted to our hospital because of hallucinations. The anti-Parkinson medication was adapted and the patients started with rivastigmine. As a result, hallucinations no longer occurred. A 79 years old man also required short-term quetiapine because of agitation and anti-Parkinson doses were without side effects, as a result of which mobility improved. An 84 years old woman reported mild side effects of rivastigmine, without consequences, whereas her mobility appeared to be good. A 72 years old woman reported mild memory problems upon admission, which improved during admission, as did her mobility after increasing the anti-Parkinson medication doses. Treatment of rivastigmine can be useful in the therapeutic dilemma in the treatment of hallucinations in patients with Parkinson's disease (start anti-psychotic or reduce anti-Parkinson medication). In addition to adapting anti-Parkinson doses and sometimes short-term treating with an anti-psychotic, treatment with rivastigmine appears to be a quick improvement, without serious side effects. Also, mobility can improve, due to the possibility of increasing the anti-Parkinson doses, if necessary. Because of the many remaining questions, prospective randomised trials are needed.  相似文献   

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