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1.
J Natl Cancer Inst ; 52(1): 297-8, 1974 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-4810970

RESUMEN

PIP: This study describes the effects of medroxyprogesterone acetate on tumor growth and metastases in transplanted uterine adenocarcinoma cells of the rat. High-and-low-tumorigenic cloned cells of Sprague-Dawley rat uterine adenocarcinoma originally induced by 7,12-dimethylbenz (alpha) anthracene in vivo were used. Both were derived from the same parent culture. They were cultured for more than 2 years and both retained almost the same transplantability. Survival rate of cell colonies in vitro was reduced in both lines after progesterone treatment of more than 8 mcg per ml. This reduction was dose dependent. About 1 million cells suspended in .2 ml culture medium were injected sc into the interscapular region of isologous newborn rats. At 5 weeks these rats were given .5 mg medroxyprogesterone acetate twice a week for 2 weeks. At 7 weeks they were killed. High-tumorigenic cells produced growing tumors in all newborn rats. About a third of these rats died of metastases during the 7-week observation period. Tumors produced by low-tumorigenic cells grew slowly and occasionally regressed without metastases to the lung. Tumors in female rats were larger than those in males. Enhancement of tumor growth and metastases by this progesterone compound was observed in rats inoculated with low-tumorigenic cells as compared to controls. The enhancement was not significant in tumors produced by high-tumorigenic cells. The progesterone may act immunosuppressively in vivo, or make alterations in environmental conditions of the tumors.^ieng


Asunto(s)
Adenocarcinoma/etiología , Células Cultivadas/efectos de los fármacos , Medroxiprogesterona/farmacología , Neoplasias Uterinas/etiología , Animales , Femenino , Neoplasias Pulmonares , Masculino , Metástasis de la Neoplasia , Trasplante de Neoplasias , Ratas , Trasplante Homólogo
2.
J Natl Cancer Inst ; 56(4): 839-41, 1976 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1255802

RESUMEN

Age, age at menopause, and calendar year at menopause were controlled as factors related to estrogen use. Data on 90 breast cancer patients and 83 conrols--all of whom had a natural menopause--showed no relationship between breast cancer and estrogen usage after the start of menopause symptoms.


PIP: 90 breast cancer patients aged 50-64 were compared with 83 controls matched for age, race, and socioeconomic class to determine the relationship between administration of exogenous estrogens and breast cancer when the factors of age, age at menopause, and calendar year were controlled. No harmful effect of estrogen administration was demonstrat ed, but a previous finding by the authors of a beneficial effect was neg ated. It is suggested, however, that there are still too many confounding factors in a study of this type for a harmful association to be revealed, and it is recommended that a case-control study be carried out in a large prepaid medical care system.


Asunto(s)
Neoplasias de la Mama/etiología , Estrógenos/efectos adversos , Factores de Edad , Femenino , Humanos , Menopausia , Persona de Mediana Edad , Estudios Retrospectivos
3.
J Natl Cancer Inst ; 51(1): 209-24, 1973 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-4352748

RESUMEN

PIP: The antifertility drug, Enovid, was tested for possible carcinogenicity in female mice of 5 specially selected strains: BALB/c, C3H, C3HfB, A, and C57BI. Enovid was chosen for testing since it is one of the most widely used oral contraceptives. The 5 strains of mice provided maximum genetic variation in the test animals. The drug was fed at 3 dose levels: 5 mcg/gm, 10 mcg/gm and 20 mcg/gm of food. The lowest dose did not prevent reproduction. The 10 mcg dose prevented some females from reproducing. The 20 mcg dose prevented all females from reproducing. The strains of mice differed in their response to Enovid. Weight gain was reduced in all strains. Effect on life-span varied, partly because of the tumors. Cervical and vaginal lesions showed invasion of the epithelium into the stroma but was limited, with few exceptions to the BALB/c females. In the BALB/c strain these lesions occurred in controls as well, but showed more progression and a higher incidence with the highest dose of Enovid. None of these lesions appeared grossly as tumors and none had extended beyond the vaginal wall or metastasized. They were observed only on histologic sections. Neither ovarian nor mammary gland tumors were increased in any strain. In the C3H strain such tumors seemed to be inhibited. In the C3HfB strain there was some inhibition of hepatomas and in the BALB/c strain some inhibition of adrenocortical adenoma. Chromophobe adenomas of the hypophysis were significantly increased in old C57BI females treated with the highest dose of Enovid. Offspring of Enovid-treated females showed no abnormalities. Enovid increased the occurrence and may have advanced the progression of epithelial lesions of the cervix and vagina of old BALB/c females. A study of the lesions in untreated females of this strain might help the understanding of carcinoma in situ in women and possibly the appearance of adeno-carcinoma of the vagina of young women whose mothers had been treated with stilbestrol during the first trimester to maintain pregnancy. Other neoplasms in this strain were not increased by the Enovid therapy. In the C3H strain mammary tumors were reduced by the Enovid and those that did occur were found later than in controls. Results from experimental animals should be applied to humans with care. Such results are of greatest value in directing attention to certain areas for investigation.^ieng


Asunto(s)
Anticonceptivos Orales/toxicidad , Mestranol/toxicidad , Neoplasias/inducido químicamente , Noretinodrel/toxicidad , Adenoma Cromófobo/inducido químicamente , Neoplasias de las Glándulas Suprarrenales/inducido químicamente , Animales , Peso Corporal/efectos de los fármacos , Carcinoma/inducido químicamente , Carcinoma Hepatocelular/inducido químicamente , Anticonceptivos Orales/administración & dosificación , Combinación de Medicamentos , Femenino , Neoplasias Hepáticas/inducido químicamente , Neoplasias Mamarias Experimentales/inducido químicamente , Ratones , Ratones Endogámicos A , Ratones Endogámicos BALB C , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , Neoplasias Experimentales/inducido químicamente , Neoplasias Ováricas/inducido químicamente , Neoplasias Hipofisarias/inducido químicamente , Enfermedades del Cuello del Útero/inducido químicamente , Enfermedades Vaginales/inducido químicamente
4.
Cancer Res ; 41(5): 1772-7, 1981 May.
Artículo en Inglés | MEDLINE | ID: mdl-7214344

RESUMEN

The purpose of this study was to characterize the effects of two functionally diverse steroids, 17 beta-estradiol and medroxyprogesterone acetate (MPA), on MtTW15 rat mammosomatotropic pituitary tumor growth and hormone production. Steroid responsiveness, as well as the hormonally autonomous nature of the tumor, was studied by treating both male and female tumor-bearing rats for 7 weeks with weekly injections of either 17 beta-estradiol (600 ng/g body weight/week) or MPA (200 microgram/g body weight/week) and, subsequently, comparing both the tumor weights and the in vivo production of growth hormone (GH) and prolactin (PRL) among the treatment groups. Large tumors (6 to 20 gm) were obtained in all treatment groups, indicating hormonal autonomy; however, tumors were markedly smaller, on the average, in untreated males an ovariectomized females. Treatment of such rats with 17 beta-estradiol stimulated tumor growth. Radioimmunoassay of tumor and serum GH and PRL levels in all treatment groups indicated the following: (a) tumors from untreated male or female hosts did not favor the production of one hormone over the other to any great extent; (b) MPA, however, promoted significant increases (p less than 0.05) in GH production in both male and female tumor-bearing rats while having little effect on the production of PRL; and (c) 17 beta-estradiol significantly inhibited (p less than 0.05) GH production and promoted PRL production by tumors borne by either sex. Selected studies utilizing multiple doses of MPA (1 to 500 microgram per gm body weight per week) and 17 beta-estradiol (10 to 800 ng per gm body weight per week) were accomplished and demonstrated that hormone production can be influenced in a dose-related manner. These results indicated that the estrogen-induced MtTW15 rat pituitary tumor is hormonally autonomous, yet divergently responsive to two different classes of steroidal compounds, thus making this tumor line an appropriate model for the study of hormonally responsive pituitary tumor cells.


PIP: The purpose of this study was to characterize the effects of 2 functionally diverse steriods, 17beta-estradiol and (MPA) medroxyprogesterone acetate on MtTW15 rat mammosomatotropic pituitary tumor growth and hormone production. Steroid responsiveness, as well as the hormonally autonomous nature of the tumor, was studied by treating both male and female tumor-bearing rats for 7 weeks with weekly injections of either 17beta-estradiol (600 ng/g body weight/week) or MPA (200 mcg/g body weight/week) and, subsequently, comparing both the tumor weights and the in vivo production of (GH) growth hormone and (PRL) prolactin among the treatment groups. Large tumors (6 to 20 gm) were obtained in all treatment groups, indicating hormonal autonomy; however, tumors were markedly smaller, on the average, in untreated males and ovariectomized females. Treatment of such rats with 17beta-estradiol stimulated tumor growth. Radioimmunoassay of tumor and serum GH and PRL levels in all treatment groups indicated the following: (a) tumors from untreated male or female hosts did not favor the production of 1 hormone over the other to any great extent; (b) MPA, however, promoted significant increases (p 0.05) in GH production in both male and female tumor-bearing rats while having little effect on the production of PRL; and (c) 17-estradiol significantly inhibited (p 0.05) GH production and promoted PRL production by tumors borne by either sex. Selected studies utilizing multiple doses of MPA (1 to 500 mcg/gm body weight/week) and 17 beta-estradiol (10 to 800 ng/gm body weight/week) were accomplished and demonstrated that hormone production can be influenced in a dose-related manner. There results indicated that the estrogen-induced MtTW15 rat pituitary tumor is hormonally autonomous, yet divergently responsive to 2 different classes of steroidal compounds, thus making this tumor line an appropriate model for the study of hormonally responsive pituitary tumor cells.


Asunto(s)
Estradiol/farmacología , Hormona del Crecimiento/sangre , Medroxiprogesterona/farmacología , Neoplasias Hipofisarias/patología , Prolactina/sangre , Animales , Castración , Relación Dosis-Respuesta a Droga , Femenino , Masculino , Tamaño de los Órganos , Neoplasias Hipofisarias/metabolismo , Ratas , Factores Sexuales , Útero/anatomía & histología
5.
Adv Cancer Res ; 49: 285-401, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3314396

RESUMEN

PIP: Adverse and beneficial effects, especially with regard to mortality rates, of oral contraceptives (OC) are reviewed. In 1980 approximately 80 million women used OCs worldwide. OCs were first marketed in the United States in the 1960's, but by the 1980's low-dose combination pills with less estrogen and progesterone content became widespread along with the minipill, injectable preparations depo- medroxyprogesterone DMPA, and norethindrone containing capsules. Relative disease risk estimates are based on cohort studies and case- control studies. The Royal College of General Practitioners RCGP Oral Contraceptive Study of 1974 involved 46,000 women aged over 15 (50% were OC users, 50% were nonusers) the Oxford Family Planning Association Contraceptive Study of 1976 recruited 17,032 women aged 25-39, 56% of whom used OCs, and the Walnut Creek Contraceptive Drug Study of 1981 studied 16,638 women aged 18-54 of whom 28% were OC users and 33% were former users. A somewhat elevated mortality among ever-users of OCs in the order of 20% seems to be indicated by these studies mostly attributable to diseases of the circulatory system. Current OC use is also a risk factor in thrombotic stroke of the order of 4 or 5, but former use of OCs lowers the risk to 2. The effect of OC dose and formulation, duration of use, and predisposing factors on hemorrhagic and thrombotic stroke appears to be inconclusive with varying data from different studies. There is evidence for some increase in ischemic heart disease among current OC users, and also a 2-fold increase of myocardial infarction (MI) when smoking, serum cholesterol, and hypertension is taken into account, moreover higher estrogen dosage also contributes to a higher incidence of MI. There is also a 5-fold increase of venous thromboembolism among OC users induced by duration of use and estrogen potency, as OCs seem to promote atherogenesis, although the roles of progesterone and estrogen are conflicting. combination pills reduce the rate of endometrial cancer, provided protection against ovarian cancer, and do not seem to increase breast cancer incidence, although the relative risk of cervical cancer is elevated. Mortality risks with older OCs outweigh the benefits.^ieng


Asunto(s)
Anticonceptivos Orales Combinados/efectos adversos , Anticonceptivos Secuenciales Orales/efectos adversos , Anticonceptivos Orales/efectos adversos , Neoplasias/inducido químicamente , Enfermedades Vasculares/inducido químicamente , Humanos , Riesgo
6.
Biochim Biophys Acta ; 244(3): 618-24, 1971 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-5160423

RESUMEN

PIP: This study demonstrated that the human placenta possesses an adenyl cyclase system responsive to catecholamines and sodium flouride (NaF). 2.5 gm human term placentas were homogenized, centrifuged, washed, resuspended, and used as the enzyme system when placed with various agents. Incubations and the determination of adenosine 3', 5' monophosphate (cyclic AMP) formed were performed. Samples stimulated by .0001 M catecholamines (L-epinephrine or L-norepinephrine) or .01 M NaF had higher levels of cyclic AMP than the controls (p. 005 for catecholamine-treated samples and p. 001 for NaF-treated samples). A concentration of .0001 M L-epinephrine or L-norepinephrine appeared to be a maximum effective dose and .0000001 M a minimum. L=epinephrine was 10 times as effective in the stimulation as L-norepinephrine. With .0001 M, 499 and 439 pmoles/10 minutes per 25 mg of tissue was formed, whereas in the control (no added hormones) 256 pmoles/10 minutes were formed. 3.2% ethanol activated the system by a small amount (p.02). Propranolol alone did not appear to have any effect; however, the effect of .0001 M L-epinephrine was reduced by 95% in the presence of .00001 M propranolol. Propranolol had no effect on NaF-stimulated activity.^ieng


Asunto(s)
Adenilil Ciclasas , Placenta/enzimología , Adenosina Trifosfato , Isótopos de Carbono , Antagonismo de Drogas , Activación Enzimática , Epinefrina/antagonistas & inhibidores , Epinefrina/farmacología , Etanol/farmacología , Femenino , Fluoruros/farmacología , Humanos , Cinética , Norepinefrina/farmacología , Placenta/efectos de los fármacos , Embarazo , Propranolol/farmacología , Sodio/farmacología , Estimulación Química
7.
Diabetes Care ; 3(4): 557-60, 1980.
Artículo en Inglés | MEDLINE | ID: mdl-7006945

RESUMEN

Experience in a large diabetic clinic has confirmed the suspicion that insulin-dependent diabetic women are at considerably increased risk of thromboembolic disease if they take combined estrogen/progestogen oral contraceptive preparations. The most obvious alternative, an intrauterine device, is associated with an unexpectedly high failure rate, probably because of an unusual metabolic interaction with the diabetic endometrium. In a small group of diabetic women the progestogen-only pill was found to be a successful form of contraception not associated with any side effects except for menstrual irregularities. For most diabetic women the choice of contraceptive should therefore be between a progestogen-only pill and a mechanical method. Female sterilization and injectable progesterone each have their place in particular circumstances. Careful counseling of each patient is essential to ensure the best choice of contraceptive and correct application of the chosen method.


PIP: Experience in a clinic for diabetics is recounted in terms of successful methods of contraception for the insulin-dependent woman. Earlier reports of increased risk to side effects (especially thromboembolic disease) and failure in women with diabetes using combined (estrogen/progestin) oral contraception were confirmed. The failure rate could be lowered by allowing the women to adjust their insulin dose, but the incidence of thrombotic disorder remains high. Of 120 insulin-dependent women taking the combined pill (compared with 156 nonuser diabetics) 6 patients had thrombotic episodes, whereas none of the controls did. The use of IUDs is discouraged among diabetic women because of an extremely high failure rate, probably caused by an unusual metabolic interaction with the diabetic endometrium. In this clinic, a small (n=45) group of women was given progesten-only contraceptives (norethisterone, .35 mg orally) and, of the 29 completing over a year on the preparation, 15 have had fairly regular bleeding and 14 have experienced very irregular cycles. Aside from the menstrual irregularity, the progesten-only pill proved successful; no pregnancies have occurred. This method is the recommended one for diabetic women. Equally successful with proper fitting and instruction were mechanical methods. Sterilization is only indicated when the family is completed or pregnancy is absolutely contraindicated.


Asunto(s)
Anticoncepción , Diabetes Mellitus , Adulto , Anticonceptivos Orales Combinados/efectos adversos , Diabetes Mellitus Tipo 1 , Femenino , Humanos , Dispositivos Intrauterinos/efectos adversos , Congéneres de la Progesterona/efectos adversos , Riesgo , Esterilización Reproductiva , Vasectomía
8.
AIDS ; 5(7): 791-6, 1991 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1654056

RESUMEN

PIP: In 1980, the US Food and Drug Administration found nonoxynol 9 to be safe and effective as a vaginal contraceptive and, with regard to local toxicity, its decision on results of only 1 animal study and the shortage of reported significant adverse effects in humans, and not on clinical trials. Even though little research has looked specifically at vaginal spermicide toxicity to genital and rectal epithelia, other research reported genital irritation rates ranging from minimal to 10%. Nevertheless most literature reviews on nonoxynol 9 concluded that any reports of local toxicity were only minimally significant. Many studies have indicated that nonoxynol 9 protects against sexually transmitted diseases, but most of these did not control for consistency and frequency of use, different sexual practices, and the use of barrier methods. In fact, 1 study revealed a positive association between nonoxynol 9 and candida infections. In vitro research has consistently demonstrated nonoxynol 9's ability to inactivate HIV, but little research in humans exists on its safety and effectiveness in preventing HIV infection. The earliest report of local toxicity involved research in Nairobi, Kenya. It revealed who used vaginal sponges with nonoxynol 9 than those who used vaginal suppositories without it. These genital ulcerations may have indeed facilitated HIV entry thereby contributing to the higher incidence of new HIV infections among those using nonoxynol 9. Another study revealed that among 71 sex workers using condoms lubricated with nonoxynol 9 in Vancouver, British Columbia 53.5% reported adverse reactions. In the recent past, published information about AIDS in the US and UK promoted use of condoms lubricated with nonoxynol 9, but did not tell users about the possible adverse effects. Since research has not verified the safety of nonoxynol 9 with regard to local toxicity, its potential benefits in HIV prevention cannot yet be determined.^ieng


Asunto(s)
Infecciones por VIH/prevención & control , Polietilenglicoles/uso terapéutico , Espermicidas , Humanos , Nonoxinol , Polietilenglicoles/efectos adversos
9.
Endocrinology ; 106(4): 1173-7, 1980 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6444575

RESUMEN

PIP: Concentrations of (GH) growth hormone, (PRI) prolactin, cortisol, progesterone, and (MPA) medroxyprogesterone acetate were determined by RIA in blood sera collected from beagle bitches 17 months after initiating treatment with MPA (75 mg/kg.3 months; n = 12) MPA vehicle (controls; n = 12), or progesterone implants which produced physiological levels of progesterone (13.8 + or - 2.1 ng/ml; n = 12). In the MPA-treated bitches, mean MPA levels were 104 + or - 6 ng/ml, mean GH levels were elevated (9.5 + or - 3.0 vs. 0.4 + or - 0.1 ng/ml; P 0.01); mean PRL levels were unchanged (13.7 + or - 2.8 vs. 12.6 + or - 1.2 ng/ml); and mean cortisol levels were suppressed (1.7 + or - 0.2 vs. 13.7 + or - 1.4 ng/ml; P 0.01) in comparison to those in control animals. None of these parameters was significantly affected by progesterone treatment. External signs of an acromegaly-like condition and large mammary gland nodules (diameters, 5 mm) were noted in, and limited to, 9 bitches with elevated ( 2.5 ng/ml) GH levels (12.8 + or - 3.0 ng/ml). These were 8 MPA-treated bitches which developed the acromegal-like condition during treatment and 1 progesterone-treated bitch which appeared acromegalic before treatment and in which the condition was considered to have developed spontaneously. The data suggest that the acromegaly-like changes and large mammary nodules in dogs administered the contraceptive progestin MPA occurred as a result of MPA-induced elevations in GH. The results do not preclude the possibility that the MPA-induced suppression of cortisol and/or the direct action of MPA on the mammary glands also contributed to mammary nodule formation. MPA-treated dogs may also provide a unique experimental model for studying chronic elevations in endogenous GH levels and for testing compounds for their ability to suppress GH levels.^ieng


Asunto(s)
Acromegalia/fisiopatología , Hormona del Crecimiento/sangre , Hidrocortisona/sangre , Glándulas Mamarias Animales/patología , Medroxiprogesterona/análogos & derivados , Prolactina/sangre , Acromegalia/inducido químicamente , Animales , Perros , Femenino , Glándulas Mamarias Animales/efectos de los fármacos , Medroxiprogesterona/farmacología , Acetato de Medroxiprogesterona
10.
J Clin Endocrinol Metab ; 60(2): 361-9, 1985 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3155524

RESUMEN

The purpose of this study was to examine the influence of altered prednisolone kinetics in patients with the nephrotic syndrome and women taking oral contraceptive steroids on mixed lymphocyte cultures (MLC). After oral and iv prednisolone treatment, blood samples were collected over 24 h. The area under the plasma concentration vs. time curve (AUC) of unbound, transcortin- bound, and albumin-bound prednisolone was determined. All plasma samples were incubated with MLCs, and the area under the inhibition vs. time curve of the MLC (AUIC), a measure of the effect over time, was calculated. The steroid concentrations required to produce half-maximal inhibition (EC50) were calculated. The 10 women taking oral contraceptives had higher AUCs of unbound and transcortin-bound prednisolone than the 10 normal subjects. The mean biological effect (AUIC value) was more pronounced in women taking contraceptive steroids. An analysis of the concentration-response curves revealed that the EC50 values of total, but not unbound, prednisolone were higher in women taking contraceptives. Compared with the normal subjects, the 9 nephrotic patients had lower total and comparable unbound AUCs of prednisolone. The AUIC values were higher whereas the EC50 values of unbound and total prednisolone were lower in the nephrotic patients. These findings indicate that the increased steroid effect in women taking oral contraceptives is explained by higher concentrations of prednisolone, while the increased effect in nephrotic patients is not attributable to the abnormal kinetics or protein binding of prednisolone.


Asunto(s)
Anticonceptivos Orales/farmacología , Linfocitos/efectos de los fármacos , Síndrome Nefrótico/sangre , Prednisolona/sangre , Adulto , Femenino , Humanos , Cinética , Prueba de Cultivo Mixto de Linfocitos , Síndrome Nefrótico/inmunología , Prednisolona/farmacología , Unión Proteica
11.
J Clin Endocrinol Metab ; 37(5): 760-4, 1973 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-4749450

RESUMEN

PIP: Medroxyprogesteroneacetate (MPA) was used to study drug-steroid interaction in an in-vitro cell culture system of human skin fibroblasts from prepubertal children. MPA did not alter testosterone utilization in 9 of the 10 cell lines studed. The addition of MPA inhibited the formation of androstanediol by nearly 53% suggesting an inhibition of 3 alpha-hydroxysteroid dehydrogenase. In 3 cell lines, dihydrotestosterone increased.^ieng


Asunto(s)
Medroxiprogesterona/farmacología , Testosterona/metabolismo , Androstanos/metabolismo , Radioisótopos de Carbono , Células Cultivadas , Niño , ADN/metabolismo , Dihidrotestosterona/metabolismo , Interacciones Farmacológicas , Femenino , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Humanos , Hidroxiesteroide Deshidrogenasas/antagonistas & inhibidores , Técnicas In Vitro , Masculino , Piel/citología , Tritio
12.
J Clin Endocrinol Metab ; 82(6): 1983-8, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9177417

RESUMEN

A high incidence of irregular uterine bleeding is the primary patient complaint limiting the utility of long term, progestin-only contraceptive agents such as Norplant. The onset of hemorrhage requires both inadequate hemostasis and impaired vascular integrity. Thus, we first tested whether Norplant-associated endometrial bleeding was accompanied by altered expression of perivascular stromal cell tissue factor (TF), the primary initiator of hemostasis. Norplant effects on TF messenger ribonucleic acid (mRNA) and protein expression by endometrial stromal cells were assessed by in situ hybridization and immunohistochemical examination of endometrial biopsies obtained from normally cycling control women (n = 14) and from patients experiencing Norplant-induced abnormal uterine bleeding (n = 24). TF mRNA and protein expression was increased 150% in secretory vs. proliferative phase endometrial specimens. By contrast, endometrial TF mRNA and protein levels were reduced during 1-6 months of Norplant treatment by about 2-fold (P < 0.05 for protein) compared to the values for control secretory phase specimens. These changes were consistent with observations that patients on Norplant begin to bleed during this interval. Further reductions of TF mRNA and protein levels to 2- and 3-fold of those in secretory phase control specimens were observed in endometria obtained after 6-12 months of Norplant therapy (P < 0.05 and P < 0.01, respectively). A modest rebound in TF mRNA and protein expression was observed after 12 months of Norplant therapy, which occurred commensurate with reduced patient complaints of abnormal uterine bleeding. Pathologically enlarged venous sinusoids were ubiquitous in endometrial specimens obtained after Norplant therapy. The combination of fragile blood vessels and reduced TF expression may account for bleeding in patients receiving Norplant therapy.


Asunto(s)
Anticonceptivos Femeninos/efectos adversos , Endometrio/metabolismo , Levonorgestrel/efectos adversos , Células del Estroma/metabolismo , Tromboplastina/metabolismo , Hemorragia Uterina/inducido químicamente , Hemorragia Uterina/metabolismo , Endometrio/efectos de los fármacos , Endometrio/patología , Femenino , Humanos , Inmunohistoquímica , ARN Mensajero/metabolismo , Coloración y Etiquetado , Tromboplastina/genética
13.
J Clin Endocrinol Metab ; 81(2): 757-62, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8636300

RESUMEN

Studies using high dose testosterone (T) administration in normal men as a male contraceptive have resulted in azoospermia rates of only 50-70%. Previous studies of T and progestogen combinations have shown comparable rates of azoospermia, but have been uncontrolled or used T in doses less than that associated with maximal suppression of sperm production. We conducted a randomized, placebo-controlled, single blind trial comparing 6 months of T enanthate administration (100 mg, im, weekly) with the same dose of T enanthate in conjunction with the progestogen levonorgestrel (LNG; 500 micrograms, orally, daily) in 36 normal men, aged 20-42 yr (n = 18 in each group). The primary end points were induction of azoospermia or severe oligospermia (< 3 million sperm/mL). The combination of T plus LNG was much more effective in suppressing sperm production than T alone. Sixty-seven percent of the T plus LNG group (12 of 18) and 33% of the T alone group (6 of 18) achieved azoospermia by 6 months (P = 0.06). Severe oligospermia or azoospermia developed in 94% of the T plus LNG (17 of 18) group compared to 61% of the T alone group (11 of 18; P < 0.05). T plus LNG also suppressed sperm production more rapidly than T alone. Time to azoospermia was 9.9 +/- 1.0 vs. 15.3 +/- 1.9 weeks in the T plus LNG and T alone groups, respectively (mean +/- SEM; P < 0.05). Serum high density lipoprotein cholesterol decreased 21.7 +/- 3.6% in men given T plus LNG (P < 0.05), compared to only a 1.8 +/- 3.8% decrease in men in the T alone group. Average weight gain was 5.3 +/- 0.8 kg in the T plus LNG group and 2.3 +/- 0.9 kg in the T alone group (P < 0.05). Acne and increase in hemoglobin were similar in the two groups. We conclude that combination hormonal therapy with T plus a progestogen might offer a reversible male contraceptive approach with a more rapid onset of action and more reliable induction of both azoospermia and severe oligospermia than T alone.


PIP: In Washington State, 36 men aged 20-42 years were randomly allocated to either the group receiving intramuscular injection of 100 mg/week testosterone (T) enanthate alone or to the group receiving the same dose T plus oral 500 mcg/day levonorgestrel (LNG). This 6-month, placebo-controlled, single blind trial aimed to compare the effectiveness of both regimes in suppressing sperm production. The combination of T plus LNG was more likely than T alone to achieve severe oligospermia or azoospermia in 6 months (94% vs. 61%; p .05). It also achieved azoospermia more quickly than T alone (9.9 vs. 15.3 weeks; p .05). Men in the T plus LNG group experienced greater reduction in serum high density lipoprotein than those in the T alone group (21.7% vs. 1.8%; p .05). They also gained more weight than those in the T alone group (5.3 vs. 2.3 kg; p .05). The two groups experienced a similar rate for acne and increase in hemoglobin. The increase in hemoglobin was significant for both groups. In conclusion, T plus LNG treatment over a 6-month period is a more effective and quicker acting method than T alone for suppressing sperm production to levels low enough to prevent pregnancy.


Asunto(s)
Anticonceptivos Masculinos/farmacología , Levonorgestrel/administración & dosificación , Espermatogénesis/efectos de los fármacos , Testosterona/administración & dosificación , Adulto , HDL-Colesterol/sangre , Hormona Folículo Estimulante/sangre , Humanos , Levonorgestrel/efectos adversos , Levonorgestrel/farmacología , Hormona Luteinizante/sangre , Masculino , Placebos , Recuento de Espermatozoides , Testosterona/efectos adversos , Testosterona/farmacología , Aumento de Peso
14.
J Clin Endocrinol Metab ; 43(6): 1226-33, 1976 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1002814

RESUMEN

Alterations in the metabolism of testosterone (T) and dihydrotestosterone (DHT) induced by diethylstilbestrol (DES) or medroxprogesterone acetate (MPA) could account for the beneficial therapeutic effect of these agents in prostatic carcinoma. To investigate this possibility we sutdied plasma kinetics of T and DHT in 17 elderly patients with prostatic carcinoma, before and after treatment with DES (1 or 5 mg/d) or MPA (10 or 30 mg/d) for 30 days. Metabolic clearance rates (MCR) were determined with the single injection technique and by use of two compartment model, plasma concentrations (PC) of T and DHT by radioimmunoassay, the per cent of T bound to plasma protein (T-binding) by charcoal adsorption of the unbound steroid. Production rate (PR) and PC of T were lower, PR and PC of DHT were higher in our patients than in normal men. With both DES regimens, PR, PC and MCR of either androgen declined; however, T was suppressed to a much greater extent than DHT. In either instance, the decrease may have been caused by direct suppression of testicular androgen synthesis and/or by decreased gonadotropin stimulation. Enhanced T-binding played an additional role in reducing the free testosterone index. High and low dose of DES were equally effective. The low dose regimen of MPA did not influence androgen metabolism. MPA in the higher dose suppressed PR and PC of T and DHT, possibly due to effects on testicular synthesis or by gonadotropin suppression as suggested for DES. In contrast to DES, MPA failed to cause profound changes in MCR of either androgen or in T-binding. When judged by its influence on the metabolism of T and DHT in prostatic carcinoma, MPA in higher doses is much less effective than either dose regimen of DES.


PIP: The effects of diethylstilbestrol(DES) and medroxyprogesterone acetate (MPA) on plasma kinetics and production of testosterone(T) and dihydrotestosterone (DHT), and on plasma protein binding of T were measured in 17 patients (50-93 years of age) suffering with metastatic carcinoma of the prostate both before and during treatment for this disease. Blood samples were obtained before injection of 30 mcCi tritiated T or tritiated DHT and at 10, 15, 20, 40, 55, 70, and 90 minutes after injection. T and DHT were measured by radioimmunoassay. Metabolic clearance rates were measured as well. Production rate (PR) and plasma concentrations (PCs) of T and DHT were higher in these patients than in normal men. When DES was given, PR, PC,and metabolic clearance rates of T and DHT declined, with T suppressed to a greater extent. There was also enhanced T-binding. In patients treated with MPA, 10 mg given for 30 enhanced T-binding. In patients treated with MPA, 10 mg given for 30 days, significantly different changes were seen in the kinetics of T and DHT in 8 patients. Patients treated with 30 mg of MPA for 30 days showed suppression of PR and PC of T and DHT. MPA failed to cause profound changes in the metabolic clearance rate of either androgen or in T-binding. These results indicate that MPA is less effective than DES.


Asunto(s)
Dietilestilbestrol/farmacología , Dihidrotestosterona/metabolismo , Medroxiprogesterona/farmacología , Neoplasias de la Próstata/metabolismo , Testosterona/metabolismo , Anciano , Dietilestilbestrol/uso terapéutico , Dihidrotestosterona/biosíntesis , Humanos , Cinética , Masculino , Medroxiprogesterona/uso terapéutico , Tasa de Depuración Metabólica/efectos de los fármacos , Persona de Mediana Edad , Neoplasias de la Próstata/tratamiento farmacológico , Testosterona/biosíntesis
15.
J Clin Endocrinol Metab ; 36(4): 706-14, 1973 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-4119677

RESUMEN

PIP: The effects of Ovral (.5 mg norgestrel and .05 mg ethinyl estradiol (EE), and Norlestrin (1 mg norethindrone acetate and .05 mg EE) in women; dydrogesterone alone and with EE in men; and norgestrel, chlormadinone, EE, cyproterone and 17-alpha-methyltestosterone in green monkeys, on plasma proteins and hormones were studied, in an attempt to reverse estrogenic changes. Both contraceptives, given for 2 cycles to 25 women, increased corticosteroid-binding globulin, cortisol, thyroxin, and plasminogen, and Norlestrin increased fibrinogen. 30 or 40 mg dydrogesterone with .01 mg EE did not block the changes induced by estrogen alone in 5 men. Plasma protein and hormone levels in monkeys, tabulated after 2.5 mcg EE, 2 mg norgestrel alone and with 2.5 mcg EE showed that the estrogen effects of EE on corticosteroid-binding globulin and haptoglobin could be reversed by norgestrel. Similarly, 12.5 mg chlormadinone blocked the action of EE on thyroxine. The experiment with cyproterone acetate and methyltestosterone did not yield significant results.^ieng


Asunto(s)
Proteínas Sanguíneas/metabolismo , Anticonceptivos Orales/farmacología , Adolescente , Adulto , Animales , Acetato de Clormadinona/farmacología , Ciproterona/farmacología , Didrogesterona/farmacología , Etinilestradiol/farmacología , Femenino , Fibrinógeno/metabolismo , Haplorrinos , Haptoglobinas/metabolismo , Humanos , Hidrocortisona/sangre , Masculino , Noretindrona/farmacología , Norgestrel/farmacología , Plasminógeno/metabolismo , Tiroxina/sangre , Proteínas de Unión a Tiroxina/metabolismo , Transferrina/metabolismo
16.
Clin Pharmacol Ther ; 39(3): 335-41, 1986 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3948473

RESUMEN

Prior studies of the association between oral contraceptives (OCs) and gallbladder disease (GBD) have yielded conflicting results. To clarify this association, a retrospective (historical) cohort study was performed on a very large data base including 1980 and 1981 Medicaid billing data from the states of Michigan and Minnesota in which 138,943 users of OCs were compared with 341,478 nonusers. The crude relative risk (RR) and 95% confidence interval (CI) for symptomatic GBD resulting in medical care was 1.14 (CI 1.09 to 1.20), with a clear dose-response (P less than 0.001). Age markedly modified the effect of OCs on GBD. The RR (CI) decreased from 3.1 (2.7 to 3.6) in women 15 to 19 years old to 1.2 (0.9 to 1.5) in women 40 to 44 years old, providing an explanation for previously conflicting reports. The effects of a number of other risk factors on GBD, some which have been controversial, were also confirmed. Adjustment for these did not change the results. In conclusion, OCs are risk factors for GBD, although the risk is of sufficient magnitude to be of potential clinical importance only in young women.


PIP: To clarify the association between oral contraceptives (OCs) and gallbladder disease (GBD), a retrospective (historical) cohort study was performed with 1980 and 1981 Medicaid billing data from the states of Michigan and Minnesota in which 138,943 users of OCs were compared to 341,478 nonusers. There were 12,292 cases of GBD that required medical attention during the 2-year study, giving an overall prevalence rate of 25.6/1000 persons over the 2 years. Of the 138,943 OC users in this study, 3889 had GBD, giving a prevalence of 28.0/1000 persons in the 2-year study. Of the 341,478 nonusers, 8403 had GBD, resulting in a prevalence rate of 24.6/1000 persons in these 2 years. The overall prevalence rate in the unexposed subjects in Michigan was higher than that in Minnesota (28.5 vs. 12.3/1000 persons in the 2 year, respectively). This difference in prevalence by state may rest in part from differences in urbanization or to the known differences in racial distribution. Comparing Minnesota with Michigan, blacks are markedly underrepresented (5.9% versus 35.6%), Indians are overrepresented (3.9% versus 0.37%), and Orientals are overrepresented (5.7% versus 0.48%). Alternatively, this difference in prevalence by state may result from administrative dissimilarities between the 2 Medicaid programs, such as in differences in the number of diagnoses that can be provided per visit and the number of visits that can be included on each claim form. The results indicate that subsequent analyses need to be state specific or state adjusted. The crude relative risks confidence intervals for the effect of OCs on GBD were 1.14 overall, 1.08 for Michigan, and 1.39 for Minnesota. While the proportion of subjects using OCs decreased with advancing age, the prevalence of GBD increased steadily with age in both users and nonusers. Stratification by 5-year age intervals revealed age to be a strong modifier of the effect of OCs on GBD, with younger women at a higher risk of GBD from OCs than middle-aged women. The effects of a number of other risk factors on GBD also were confirmed. Adjustment for these failed to change the results. The relationship between OCs and GBD remained statistically significant even after age, state, and each confounding variable was controlled for logistic regression. In sum, OCs are risk factors for GBD, although the risk is of sufficient magnitude to be of potential clinical importance only in young women.


Asunto(s)
Anticonceptivos Hormonales Orales/efectos adversos , Enfermedades de la Vesícula Biliar/inducido químicamente , Adolescente , Adulto , Factores de Edad , Computadores , Femenino , Enfermedades de la Vesícula Biliar/complicaciones , Humanos , Registros Médicos , Michigan , Minnesota , Grupos Raciales , Estudios Retrospectivos , Riesgo
17.
Clin Pharmacol Ther ; 54(5): 540-5, 1993 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8222497

RESUMEN

The objective of this multicenter randomized clinical trial was to compare the efficacy, acceptability, and occurrence of side effects associated with the oral versus vaginal route of administration of contraceptive pills. Eight hundred nineteen healthy, parous women of reproductive age were recruited at family planning clinics and research centers, members of the South to South Cooperation in Reproductive Health, in seven countries of the developing world. These women were randomly assigned to use either oral or vaginal administration of the same contraceptive pill, which contained 250 micrograms levonorgestrel and 50 micrograms ethinyl estradiol. No statistically significant differences were found in discontinuation rates between the two groups after 1 year. Involuntary pregnancy rates after 1 year were not statistically significantly different between the two groups. The vaginal route of administration appears to be as acceptable and efficacious as the oral route.


PIP: The objective of this multicenter randomized clinical trail was to compare the efficacy, acceptability, and occurrence of side effects associated with the oral versus vaginal route of administration of contraceptive pills. This study started in June, 1987, and data collection extended up to April, 1992, at family planning clinics and research centers, members of the South to South Cooperation in Reproductive Health, in seven countries of the developing world. The 819 subjects were from 17 to 39 years of age, had already had at least one pregnancy, had had regular menstrual cycles for 3 months before, were exposed to the risk of pregnancy, and were not using any other method of contraception. 424 were randomly assigned to use the pills orally (which contained 250 mcg levonorgestrel and 50 mcg ethinyl estradiol), whereas 395 inserted the pills vaginally. 625 subjects completed at least 6 months of use, 326 used the pills orally and 299 used the pills vaginally. 385 subjects completed 1 year of pills use, 201 in the oral group and 184 in the vaginal group. The 1-year discontinuation rate per 100 subjects per year for the oral group was 34.71 +or- 2.42, while it was 36.35 +or- 2.53 for the vaginal group. This difference was not statistically significant. The only single reason of statistically significant difference for discontinuation was "desire for pregnancy" (p = 0.444). Paired value analysis of subjects completing 12 months of study showed that women in the oral group had a statistically significant increase in weight, from a mean of 55.8 kg at admission to a mean of 56.9 kg at 6 months (p 0.05) and 57.3 kg at 1 year (p = 0.05). The mean weight of the vaginal group increased from 56.52 kg to 57.22 kg (p = 0.036) at 12 months. Significantly more complaints of vaginal discharge were recorded in women using the pills by the vaginal route (p = 0.001). However, only one subject discontinued the pills because of vaginal discharge.


Asunto(s)
Anticonceptivos Femeninos/administración & dosificación , Anticonceptivos Hormonales Orales , Administración Intravaginal , Adolescente , Adulto , Anticonceptivos Femeninos/efectos adversos , Anticonceptivos Hormonales Orales/efectos adversos , Países en Desarrollo , Femenino , Humanos , Cooperación del Paciente
18.
MMWR Morb Mortal Wkly Rep ; 33(25): 353-4, 1984 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-6427584

RESUMEN

PIP: Preliminary results from the Cancer and Steroid Hormone Survey published in 1983 suggested that there is no association between oral contraceptive (OC) use and breast cancer. However, more recent studies have indicated 1) an increased risk of developing breast cancer before 25 years of age among women who use high-progestogen combination-type OCs before age 25 years, and 2) an increased risk of breast cancer before 45 years of age among women who use OCs before their 1st term birth. To evaluate these 2 findings, data from the complete 29-month file of the Cancer and Steroid Hormone Survey (CASH) were analyzed. (The results published in 1983 reflected only 10 months of data.) 1st, analysis of the relative risk of breast cancer by duration of use of high-progestogen combination OCs before age 25 years revealed no significant associations, even when women who had never used OCs were used as a reference group and the analysis was restricted to women still nulliparous at age 25 years. 2nd, the relative risk of breast cancer before age 45 years in parous women who used OCs before their 1st term pregnancy compared to those who were nonusers before the 1st term pregnancy was not elevated. It is possible that methodologic differences between the population-based Cancer and Steroid Hormone Survey and the 2 other studies account for these discrepant results.^ieng


Asunto(s)
Neoplasias de la Mama/inducido químicamente , Anticonceptivos Hormonales Orales/efectos adversos , Anticonceptivos Orales/efectos adversos , Adulto , Factores de Edad , Femenino , Humanos , Riesgo
19.
Am J Clin Nutr ; 20(5): 452-6, 1967 May.
Artículo en Inglés | MEDLINE | ID: mdl-6023855

RESUMEN

PIP: This is an extension of work recently reported by Rose regarding young women using a combination of progesterone and estrogen for ovulation control. The 10 subjects studied had an abnormal xanthurenic acid excretion after a loading dose of tryptophan. After treatment with 2.5 mg norethynodrel and .1 mg mestranol (Enovid-E) from Days 5 to 24 of the the cycle, 24-hour urine specimens were collected before and after administration of 2 gm of L-tryptophan. They were then given 25 mg of pyridoxine hydrochloride 4 times a day during the 48 hours required to repeat the tryptophan loading test. Controls were 18 healthy women not taking drugs. Metabolites of trytophan determined were indican, anthranilic acid glucuronide, 0-aminohippuric acid, kynurenic acid, acetylkynurenine, kynurenine, 3-hydroxykynurenine, xanthurenic acid, and N-methyl-2-pyridone-5-carboxamide. Urine specimines were analyzed for these and for 4-pyridoxic acid taking usual precautions to avoid dietary factors or drugs which might vitiate the results. At first the ingestion of the steroid had no significant effect on the basal excretion of urinary tryptophan metabolites. However, after the loading dose of tryptophan, the subjects taking Enovid E- excreted a mean level of 697 micro-moles of xanthurenic acid compared with a mean level of 29.8 micro-moles in controls. Some of the other metabolites were also excreted in increased quantities: 3-hydroxykynurenine, kynurenine, kynurenic acid, and acetylkynurenine. The others were excreted in normal quantities. When experimental subjects were given 100 mg/day of supplemental pyridoxine hydrochloride, tryptophan metabolism was essentially normal. These results should be considered in human metabolic studies of pyridoxine-requiring enzyme systems.^ieng


Asunto(s)
Mestranol/metabolismo , Noretinodrel/metabolismo , Ovulación/efectos de los fármacos , Piridoxina/metabolismo , Triptófano/metabolismo , Femenino , Humanos
20.
Am J Clin Nutr ; 30(3): 381-7, 1977 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-842489

RESUMEN

Effects of an oral contraceptive on plasma growth hormone and glucose tolerance were studied in two strains of rats, Sprague-Dawley, a normal strain, and BHE, a carbohydrate-sensitive strain. Ethynyl estradiol and norgestrel, combined in a dose representative of the clinical preparation of Ovral were given for 21 days. Plasma growth hormone was measured following sodium pentobarbital stimulation. In both strains fasting blood glucose levels were unchanged following oral contraceptive therapy, however, a strain difference in response to a glucose load was found. With contraceptive steroid treatment, Sprague-Dawley rats developed an impaired tolerance to glucose during the latter part of the glucose tolerance test. BHE control animals had an abnormal response to a glucose load which improved with oral contraceptive therapy. No significant correlation between growth hormone changes and changes in glucose tolerance during contraceptive steroid treatment were observed. Both strains of rats receiving oral contraceptives gained less weight than their controls, however, the difference was statistically significant only in the Sprague-Dawley strain.


PIP: The effects of Ovral (norgestrel plus ethinyl estradiol) on plasma growth hormone (GH) levels and glucose tolerance were investigated in Sprague-Dawley and a carbohydrate-sensitive strain (BHE) of rats. Sodium pentobarbitol was used to stimulate GH production. Fasting blood glucose levels were not altered by treatment with Ovral in either strain. However, under a glucose load, Sprague-Dawley rats developed an impaired tolerance during the latter part of the glucose tolerance test, while treatment with the oral contraceptive improved an impaired response to glucose load in BHE animals. A good correlation between changes in GH and glucose tolerance during treatment could not be established. Sprague-Dawley rats had a significant (p less than .01) decrease in the rate of body weight increase compared with controls.


Asunto(s)
Anticonceptivos Sintéticos Orales/farmacología , Anticonceptivos Orales/farmacología , Glucosa/metabolismo , Hormona del Crecimiento/sangre , Animales , Peso Corporal/efectos de los fármacos , Anticonceptivos Orales Combinados/farmacología , Etinilestradiol/farmacología , Femenino , Prueba de Tolerancia a la Glucosa , Norgestrel/farmacología , Ratas , Especificidad de la Especie
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