RESUMO
This study was undertaken to define the incidence and concentration of uncharged nuclear estrogen receptors (RN) in human breast cancer. The concentrations of RN and cytoplasmic uncharged receptor were determined on sucrose gradients following a 4-hr incubation at 4 degrees with 1.6 nM 17 beta-[3H]estradiol in 139 tumor specimens from 137 patients. RN was extracted from washed nuclear pellets in buffer containing 0.4 M KCl. The receptor molecule extracted had a high affinity for 17 beta-[3H]estradiol (Kd = 0.9 to 7.6 nM) and was specific for estrogen. The possibility of artifact due cytoplasmic contamination of the nuclear fraction or high-ionic-strength-induced exchange of charged nuclear receptors was rendered unlikely by validation experiments performed with pooled tumor tissue. Significant amounts of cytoplasmic uncharged receptor (greater than 7 fmol/mg protein) were found in 63.3% of the tumors. Similar significant amounts of RN were found in 29.5% of the tumors. Significant amounts of RN in the presence of undetectable cytoplasmic uncharged receptor were found in 2.9% of the tumors. The percentage of tumors that contain significant amounts of RN is approximately the same percentage of estrogen receptor-positive tumors that do not respond to ablative therapy.
Assuntos
Neoplasias da Mama/metabolismo , Receptores de Estrogênio/metabolismo , Adulto , Idoso , Neoplasias da Mama/terapia , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Glândulas Endócrinas/cirurgia , Antagonistas de Estrogênios/uso terapêutico , Estrogênios/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
The presence of estrogen receptor in 67 canine mammary lesions was correlated with pathological features of the disease. All tissue specimens were analyzed for estrogen receptor content by a sucrose gradient ultracentrifugation method previously used in analyzing human breast cancer cytosols. Pathological features of the tissues were assessed by a veterinary pathologist without knowledge of results of estrogen receptor analysis. Sixty-two (92.5%) of the tissue samples analyzed were classified as epithelial neoplastic lesions, and 38 of these (61.3%), including 24 adenocarcinomas, were estrogen receptor for positive (i.e., estrogen receptor concentration equal to or greater than 10 fmol/mg cytosol protein). All five of the nonepithelial neoplastic lesions were estrogen receptor negative. Canine and human breast cancers share common histological types and have similar biological behavior. If a significant percentage of canine mammary cancer is also estrogen dependent, the dog may be a useful model for hormonal studies and for the development of models of endocrine therapy for human breast cancer.
Assuntos
Doenças do Cão/metabolismo , Glândulas Mamárias Animais/metabolismo , Neoplasias/veterinária , Receptores de Estrogênio/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma/veterinária , Adenoma/metabolismo , Adenoma/veterinária , Animais , Carcinoma in Situ/metabolismo , Carcinoma in Situ/veterinária , Cães , Estradiol/metabolismo , Feminino , Cinética , Neoplasias/metabolismo , Sarcoma/metabolismo , Sarcoma/veterináriaRESUMO
An exchange assay has been validated and used to measure the total concentration of estrogen receptors in the nuclei of cells from human breast tumors and myometrium. Tissue homogenates were centrifuged through 1.2 M sucrose pads to separate crude chromatin from soluble ane membranous fractions. The yield of DNA by this procedure was approximately 80%. Total binding sites were measured by incubating the sedimented pellets with tritiated estradiol at 30 degrees for 60 min and then precipitating the receptor-steroid complexes with protamine sulfate. Saturation analysis by this procedure provides evidence for the presence of a specific, nuclear estrogen-binding site in addition to the established estrogen receptor in both these tissues.
Assuntos
Neoplasias da Mama/metabolismo , Núcleo Celular/metabolismo , Miométrio/metabolismo , Receptores de Estrogênio/metabolismo , Útero/metabolismo , Citosol/metabolismo , Feminino , Humanos , Cinética , Receptores de Estrogênio/isolamento & purificação , Valores de ReferênciaRESUMO
The studies presented here describe the effects of the nonionic detergent, Tween 80 and the reducing agent, dithiothreitol (5 mM), on the quantitation of specific nuclear estrogen binding sites, both estrogen receptors (ER) and type II estrogen binding sites (EBS), in human breast cancer. Neither of these agents had any significant effect on the apparent Kd of the amount of ER measured; however, both had a dramatic effect on the amount of type II EBS measured. Two antiestrogens, tamoxifen and nafoxidine, were also tested for their ability to bind to ER and type II EBS in human breast tumors. Both of the antiestrogens were capable of competing with estradiol for ER and type II EBS. We also present a series of 25 individual human breast cancer specimens which were analyzed for cytoplasmic ER and progesterone receptor by sucrose density gradient centrifugation and for nuclear ER and type II EBS by the sucrose pad assay. Sixty-four % (16 of 25) of the tumors contained nuclear ER and type II EBS when analyzed by the sucrose pad assay. The concentration of type II EBS was strongly correlated to the concentration of cytoplasmic progesterone receptor.
Assuntos
Neoplasias da Mama/metabolismo , Núcleo Celular/metabolismo , Miométrio/metabolismo , Receptores de Estrogênio/metabolismo , Útero/metabolismo , Citosol/metabolismo , DNA de Neoplasias/metabolismo , Estradiol/metabolismo , Feminino , Humanos , Cinética , Nafoxidina/farmacologia , Polissorbatos/farmacologia , Receptores de Estrogênio/efeitos dos fármacos , Valores de Referência , Tamoxifeno/farmacologiaRESUMO
Dihydrotestosterone heptanoate (DHT-hp), a seven-carbon fatty acid ester of DHT, was synthesized, and its pharmacokinetics and effects on hypothalamic-pituitary-testicular function were determined in men and pubertal boys. Plasma DHT levels markedly increased 24 h after im injection of DHT-hp, reached their peak during the first week, and fell to baseline levels after 4-6 weeks. An estimated 43-55% of DHT-hp was converted to DHT 4-6 weeks after injection. Plasma testosterone, estradiol, LH, and FSH levels decreased by 4 days after DHT-hp injection, were lowest during the second week, and returned to baseline values after 4-6 weeks. The LH and FSH responses to GnRH were diminished by chronic administration of DHT-hp to pubertal boys at 3-week intervals for 15 weeks. The affinity of DHT-hp was 100 times less than the affinity of DHT for the human androgen receptor, and no affinity for the estrogen receptor in breast tissue could be demonstrated. Since DHT is a nonaromatizable androgen, and neither DHT nor DHT-hp binds readily to the estrogen receptor, suppression of LH and FSH secretion by this drug probably occurs via an androgen-dependent mechanism. Receptor binding and pharmacokinetic data indicate that unesterified DHT is the active principle. DHT-hp is a useful derivative of DHT, since prompt, predictable, and sustained rises in DHT occur after its administration.
Assuntos
Di-Hidrotestosterona/análogos & derivados , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Testículo/efeitos dos fármacos , Adulto , Di-Hidrotestosterona/síntese química , Di-Hidrotestosterona/metabolismo , Di-Hidrotestosterona/farmacologia , Estradiol/metabolismo , Gonadotropinas Hipofisárias/metabolismo , Humanos , Sistema Hipotálamo-Hipofisário/metabolismo , Cinética , Masculino , Pessoa de Meia-Idade , Hormônios Liberadores de Hormônios Hipofisários , Testículo/metabolismo , Testosterona/metabolismoRESUMO
The purpose of this article is to provide the author's perspective on whether it is likely or feasible that those working in the health care domain will adapt and use lessons learned by those in the industrial domain. This article provides some historical perspective on the changes brought about in the industrial domain through the introduction of new technologies, including information technologies. The author discusses how industrialization catalyzed changes in health care delivery that paralleled but lagged behind those of the broader U.S. economy. The article concludes that there is ample reason for those interested in improving the quality and effectiveness of health informatics to systematically evaluate information technology strategies used in the industrial domain. Finally, it outlines some challenges for health informaticians and a number of factors that should be considered in adapting lessons from industry to the health care domain.
Assuntos
Atenção à Saúde/tendências , Indústrias/organização & administração , Gestão da Informação , Transferência de Tecnologia , Computadores , Atenção à Saúde/história , Atenção à Saúde/organização & administração , História do Século XX , Indústrias/tendências , Sistemas de Informação , Modelos Organizacionais , Estados UnidosRESUMO
A patient with a progesterone-producing granulosa cell carcinoma is the basis of this report. Seven years after initial surgical therapy pelvic masses were palpated. At laparotomy the recurrence of tumor was confirmed, and many nonresectable metastases were discovered on the surface of the liver and on the mesentery of the bowel. An exceedingly high plasma progesterone level of 6270 pg/ml was obtained in the postoperative period. During 12 months of single agent chemotherapy with melphalan, serial plasma progesterone assays declined to 310 pg/ml. Complete tumor regression was subsequently confirmed by laparoscopy. Evaluation of progesterone levels in patients with granulosa cell tumors is recommended to determine the incidence of this finding and to further assess its value in following response to therapy.
Assuntos
Tumor de Células da Granulosa/sangue , Hormônios Ectópicos/sangue , Neoplasias Ovarianas/sangue , Progesterona/sangue , Idoso , Feminino , Tumor de Células da Granulosa/cirurgia , Humanos , Histerectomia , Melfalan/administração & dosagem , Metástase Neoplásica , Neoplasias Ovarianas/cirurgiaRESUMO
Over the past decade, the chief information officer (CIO) in the health care enterprise has gained recognition as a member of the senior management team based on an understanding of business processes and business language. The clinical information system (CIS) in the health care environment poses a new frontier for CIOs, who are generally unfamiliar with both clinical languages and clinical processes. The authors discuss the role formal informatics training can have in preparing learners for future careers as CIOs in CIS environments. The health information management (HIM) specialization within the MBA program at the University of Illinois at Chicago is one example of an educational program designed to train future CIOs who can manage the business, technical, and clinical aspects of the health care environment.
Assuntos
Gestão da Informação , Sistemas de Informação Administrativa , Informática Médica/educação , Humanos , Estados Unidos , Recursos HumanosRESUMO
Organizations face a unique challenge over the next decade. When technology was expensive, it was arguably necessary to use an undifferentiated, or monolithic, model for computer-based solutions to problems. This has fundamentally changed. Technology is now so inexpensive that solutions are not limited by costs, but rather by how well the implementors understand the many different problem domains. Thus, academic medical centers are faced with successive waves in information technology use. First, there will be a wave of innovation, driven by the need for specialization in problem solving. This will be followed by consolidation of the best of the approaches into the core systems of the institution. The average level of heterogeneity (cost) will be higher, but the overall quality of the solutions (benefit) will also be higher. If one can develop a strategy for managing and creatively limiting the heterogeneity, the cost-benefit ratio will be much more favorable. While there may be other strategies that will do this, we support the use of a strategy centered on enterprise networking. This strategy emphasizes not simply technology but also the cultural and organizational changes that empower innovation--within a framework that makes it possible to simply implement interoperability and data sharing within nearly all solutions. The organizations that survive the coming period of change and external pressure will be those that do the best job of managing their resources. Information will continue to be one of the most important resources.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Centros Médicos Acadêmicos , Pessoal Administrativo , Redes de Comunicação de Computadores , Liderança , Centros Médicos Acadêmicos/organização & administração , HumanosRESUMO
Laboratory data from Milan and Houston were evaluated to determine the extent to which the distribution of estrogen receptor (ER) and progesterone receptor (PgR) has changed with time. Results from over 11,500 ER and over 8,200 PgR determinations (6,194 ER and 3,127 PgR from Milan) were analyzed. All assays in Milan were performed by a dextran-coated charcoal method and in Houston by a sucrose density-gradient method. The data demonstrate a time-dependent, upward drift in the amount of ER and PgR detected, with the effect most pronounced at the lower end of the distribution curves. We attribute this change to optimization of all facets of the receptor assay procedures (tissue harvesting and storage) as well as to a change in breast cancer biology. These results suggest that studies correlating certain biological parameters with receptor status (whether using qualitative or quantitative scales) need to be re-examined. For example, a population of 349 node-negative patients who did not receive any adjuvant treatment was studied in Milan to determine any association between disease-free survival (DFS) and receptor status. If the "historical" threshold values (10 fmol/mg protein) were used to determine receptor status, no significant difference in DFS at 5 years was detected. Even the combination of ER and PgR did not improve the predictive power of receptor status. In the premenopausal subgroup, ER status did predict the 5-year DFS. However, if the threshold value for PgR was adjusted to 25 fmol/mg protein, patients with ER-positive, PgR-positive tumors had significantly better 5-year DFS than patients with ER-negative, PgR-negative tumors. In addition, PgR status alone was associated with significantly improved 3-year DFS if the subgroups of PgR less than 5 fmol/mg protein and PgR greater than 100 fmol/mg protein were compared. We conclude from these data that: 1) historical threshold values for receptor positivity should be re-examined in all laboratories; 2) studies involving receptor results determined over an extended period of time should attempt to "normalize" these results; and 3) the quantitative assessment of receptor status should be used whenever possible.
Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/patologia , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Neoplasias da Mama/cirurgia , Feminino , Seguimentos , Humanos , Itália , Mastectomia , Prognóstico , TexasRESUMO
While the use of three-dimensional models has been shown to be useful clinically, the specialized computational equipment and expertise necessary for their construction and use keeps these tools out of reach of most physicians. This paper explores the construction of a Web-based Java application that allows medical radiological models to be built on a remote server and navigated locally on the physician's desktop PC. This paper will also address issues that arose from a public, unrestricted testing of usability over the Internet, such as model size management, easy navigation, processor loading and security. Based on observations and data collected, we suggest what steps are necessary to make a telemedicine application useable in a true clinical setting.
Assuntos
Processamento de Imagem Assistida por Computador/instrumentação , Sistemas de Informação em Radiologia , Interface Usuário-Computador , Humanos , Internet , SoftwareRESUMO
The information base used in the biomedical enterprise, already large, continues to expand at a striking rate. Networking and desktop computing technology is playing a more important role in the operations of academic medical centers. Integration efforts aimed at enhancing information access by using distributed computing are very substantial technical challenges. However, if these integration efforts focus only on the technical aspects, they are doomed to failure. New organizational approaches are also needed. This paper describes an new model for enhanced information services. This model calls for the central information supplier to provide a set of core services. Users, who may be individuals or units and generally have more insight into the nature of their problems, will be encouraged to add value to these core services in the form of specialization or customization to meet their unique and critical needs. This model provides a way to adapt and transform current organizational elements to effectively use the large information technology investments and to meet the increasing challenges of biomedical information use.
Assuntos
Centros Médicos Acadêmicos , Serviços de Informação/organização & administração , Modelos Teóricos , Resolução de ProblemasRESUMO
This article describes a networking and integration strategy in use at the University of Michigan Medical Center. This strategy builds upon the existing technology base and is designed to provide a roadmap that will direct short-term development along a productive, long-term path. It offers a way to permit the short-term development of incremental solutions to current problems while at the same time maximizing the likelihood that these incremental efforts can be recycled into a more comprehensive approach.
Assuntos
Sistemas Integrados e Avançados de Gestão da Informação , Faculdades de Medicina , Redes LocaisRESUMO
Forty-nine specimens of carcinoma of the breast were analyzed for estrogen receptor content using the sucrose gradient method and a histochemical method using a conjugate of estradiol (6-BSA-Fluor-CMO-17 beta-estradiol). The specimens analyzed by the histochemical method were graded for fluorescent intensity, percentage of cells fluorescing, and cellularity. Only 53.1% (26/49) of the specimens were classified into the same three categories (positive, negative and ambiguous) as classified by the biochemical assay. If the negative and ambiguous categories were combined, the degree of correspondence rose to only 63.3% (31/49). Because the classification scheme was arbitrary and because the results of the biochemical assay might be correlated with one or more factors, univariate and multivariate analyses were used to examine the data for any underlying relationships. Only the age of the patient was significantly correlated with the results of the biochemical assay. Importantly, neither the percentage of cells fluorescing nor the fluorescent intensity was correlated with the results of the biochemical assay. Terms to account for various interactions of parameters did not enhance the association with the biochemical results. While this histochemical assay may eventually prove to be effective in selecting patients for endocrine therapy, it does not seem to be a substitute for the standard biochemical assay for estrogen receptors presently used.
Assuntos
Neoplasias da Mama/metabolismo , Receptores de Estrogênio/análise , Adulto , Fatores Etários , Idoso , Centrifugação com Gradiente de Concentração , Feminino , Humanos , Microscopia de Fluorescência , Pessoa de Meia-Idade , ProbabilidadeRESUMO
The question of the presence of specific glucocorticoid receptors in the rat uterus was reassessed. A high speed supernatant obtained from uteri of ovariectomized or intact 45-day old rats was incubated 18 h at 4 c in the presence of [3H]triamcinolone acetonide ([3H]TA) with or without excess dexamethasone, followed by a 10 min exposure to dextran-coated charcoal. A specific uterine glucocorticoid receptor was detected with a Kd=5.1 nM and the number of binding sites equal to 1.1 pmol/uterus. [3H]dexamethasone was observed to underestimate the number of specific receptor sites, probably due to the instability of the dexamethasone-receptor complex during treatment with charcoal. In addition, unlabeled TA was unsatisfactory for determining nonspecific binding because of the cross-reactivity with the progesterone receptor also present in uterine cytosol. The uterine glucocorticoid receptor exhibited the appropriate steroid specificity. Sucrose density gradient analysis of uterine cytosol revealed peaks of dexamethasone-competable [3H]TA binding at 7.2S and 5.75 in low salt and at 4S in 0.4M KCL. Similar components were observed in cytosol and nuclear fractions, respectively, 20 min after in vivo injection of 25 mu Cl [3H]TA. The physical characteristics of the specific glucocorticoid receptor were consistent with those determined for other receptor proteins. The documentation of the presence of glucocorticoid receptors in the rat uterus is important physiologically because of numerous reports of glucocorticoid effects on this reproductive tissue. If receptors could not be demonstrated, extensive studies of the mechanism of these effects would be necessary for a full understanding of uterine endocrinology.
Assuntos
Receptores de Glucocorticoides/metabolismo , Receptores de Esteroides/metabolismo , Útero/metabolismo , Adrenalectomia , Animais , Castração , Núcleo Celular/metabolismo , Centrifugação com Gradiente de Concentração , Citosol/metabolismo , Dexametasona/metabolismo , Feminino , Cloreto de Potássio/farmacologia , Ratos , Ratos Endogâmicos , Receptores de Glucocorticoides/efeitos dos fármacos , Triancinolona Acetonida/metabolismoRESUMO
Cytosols of 159 primary breast carcinomas were assayed for estrogen and progesterone receptors and 60 of these for carcinoembryonic antigen (CEA). The relationships of pathologic and clinical features previously shown to be of prognostic significance and the biochemical parameter measured were examined. It was found that degree of histologic differentiation was significantly related to receptor status. There were significant inverse relationships between estrogen receptor and lymphocytic infiltrate as well as tumor necrosis. Relationships between estrogen, but not progesterone, receptor and patient age, menstrual status, and race existed. Cytosol CEA, on the other hand, related only to pathologic stage and not to histologic differentiation and other pathologic variables. Therefore, steroid receptors and CEA appear to provide information about different biologic characteristics of a carcinoma. Furthermore, the information provided by CEA appears to be independent of many known pathologic, clinical, and biochemical prognostic indicators.
Assuntos
Neoplasias da Mama/análise , Antígeno Carcinoembrionário/análise , Carcinoma/análise , Citosol/análise , Receptores de Esteroides/análise , Fatores Etários , Neoplasias da Mama/patologia , Feminino , Humanos , Menstruação , Grupos Raciais , Receptores de Estrogênio/análise , Receptores de Progesterona/análiseRESUMO
The effect of prostaglandin F2 alpha (PGF2 alpha) on endocrine and ovarian function during the early luteal phase of the domestic cat was investigated. Queens were induced to ovulate and then injected subcutaneously with 0.5-5.0 mg PGF2 alpha/kg body weight. The greatest dose was found to approach toxicity. Concentrations of progesterone were similar in cats following treatment with PGF2 alpha compared to values of controls. Development and regression of corpora lutea as determined by serial laparoscopy were similar in all groups. These data indicate that PGF2 alpha at the tested dosages, given during the early luteal phase is not luteolytic in this species and suggest that these regimens would be ineffective for the premature termination of pseudopregnancy.
Assuntos
Estro/efeitos dos fármacos , Ovário/fisiologia , Progesterona/sangue , Prostaglandinas F/farmacologia , Animais , Gatos , Corpo Lúteo/citologia , Feminino , Ovário/efeitos dos fármacos , GravidezRESUMO
The ductus deferens smooth muscle tumor cell line (DDT1MF-2) contains receptors for, and is stimulated by, androgens. Cells cultured in the absence of androgens maintain a basal level of androgen receptors. Following incubation with various concentrations of the synthetic androgen methyltrienolone (R1881) for 1-6 h, the concentration of these receptors increased from 6.0 to 12.2 fmol/micrograms of DNA, while the equilibrium dissociation constant (Kd) of 0.5 nM for this steroid remained unchanged. The steroid-induced increase in androgen receptor levels was specific for androgens and dependent upon protein synthesis. The mechanism of receptor augmentation was examined by utilization of isotopically dense amino acids to determine rates of receptor appearance and degradation in the presence or absence of [3H]R1881. In the absence of androgens, the half-life of the androgen receptor was 3.1 h, with a rate constant (kD) of 0.22/h. In the presence of 1 nM [3H]R1881, however, the half-life was 6.6 h, with kD = 0.11/h. The rate constant for receptor synthesis (ks) in the absence or presence of [3H]R1881 was calculated to be 1.35 and 2.23 fmol/micrograms of DNA/h, respectively. Thus, androgen-induced androgen-receptor augmentation is explained by an increase both in receptor half-life and in rates of receptor synthesis.
Assuntos
Receptores Androgênicos/metabolismo , Receptores de Esteroides/metabolismo , Animais , Linhagem Celular , Cicloeximida/farmacologia , Estrenos/metabolismo , Neoplasias dos Genitais Masculinos , Cinética , Masculino , Metribolona , Músculo Liso , Receptores Androgênicos/efeitos dos fármacos , Receptores Androgênicos/isolamento & purificação , Congêneres da Testosterona/metabolismo , Ducto DeferenteRESUMO
Human chorionic gonadotropin levels in concentrated 24-hour urine and serum were determined by a specific radioimmunoassay of beta-human chorionic gonadotropin in 47 patients with genitourinary carcinoma. Elevated human chorionic gonadotropin levels in urine were observed in 6 of 8 patients with active testicular tumor, 3 of 14 with prostatic cancer, 2 of 10 with bladder cancer, 1 of 2 with ureteral or renal pelvic tumors and 2 of 6 with renal cancer. Of the 14 patients with positive urinary human chorionic gonadotropin 4 had undetectable human chorionic gonadotropin levels in the serum. The tumors of all 8 patients with nontesticular cancer who had increased urinary human chorionic gonadotropin levels were in an advanced clinical stage or of poor histological differentiation. Our results suggest that some nontrophoblastic carcinomas of the genitourinary system are capable of ectopic production of human chorionic gonadotropin, particularly if the malignancy is advanced or poorly differentiated. The radioimmunoassay of beta-human chorionic gonadotropin in concentrated 24-hour urine specimens enhances the sensitivity of detection of ectopic human chorionic gonadotropin production.