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1.
Oncogene ; 11(5): 863-70, 1995 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-7545806

RESUMEN

Certain embryonal tumors demonstrate a loss of heterozygosity at the parentally imprinted region of chromosome 11p15.5. It has been hypothesized that this implicates a tumor suppressor gene at this locus. The human H19 gene maps to 11p15.5, is expressed in fetal tissues including the placenta and is paternally imprinted. Here we show that the abundance of H19 transcripts in cells of two choriocarcinoma derived cell lines (JAr and JEG-3) differs greatly. While JAr cells express high levels of H19 RNA, the expression of H19 in JEG-3 cells is much lower than that of normal trophoblasts. Cells of these two cell lines were subcutaneously injected into nude mice with subsequent tumor formation. A fivefold increase in the H19 RNA level was measured in tumors derived from JEG-3 cell lines as compared to these cells before injection. However this increase in H19 RNA did not alter the clonogenicity in soft agar nor the growth rate of the cells derived from these tumors as compared to the original JEG-3 cells. Nevertheless, the cells retaining the elevated level of H19 transcripts were more tumorigenic than the original cells. We propose that there is a selection of cells expressing high levels of H19 from the total JEG-3 cell population during the microevolution of tumor formation. These observations, together with our previous publications on H19 expression in human cancers, do not support the notion of a tumor suppressor role for the H19 gene.


Asunto(s)
Coriocarcinoma/genética , Genes Supresores de Tumor , Proteínas Musculares/genética , Neoplasias Ováricas/genética , ARN no Traducido , Animales , Secuencia de Bases , Gonadotropina Coriónica/genética , Gonadotropina Coriónica Humana de Subunidad beta , Femenino , Expresión Génica , Humanos , Ratones , Ratones Desnudos , Datos de Secuencia Molecular , Fragmentos de Péptidos/genética , Embarazo , Proto-Oncogenes , ARN/análisis , ARN Largo no Codificante , Neoplasias Cutáneas/genética , Trasplante Heterólogo , Células Tumorales Cultivadas
2.
FEBS Lett ; 309(1): 25-8, 1992 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-1380925

RESUMEN

It has only recently become clear that genetic imprinting plays an important role in human embryogenesis and in processes leading to the development of pediatric cancers and other human diseases. Using a unique human tissue, the androgenetic complete hydatidiform mole, we established that the maternally inherited allele of the imprinted H19 gene is expressed. Our results also show that the paternal allele of the human IGF-II gene, a gene suspected to be parentally imprinted in humans, is expressed.


Asunto(s)
Coriocarcinoma/genética , Genes , Mola Hidatiforme/genética , Placenta/fisiología , Neoplasias Uterinas/genética , Northern Blotting , Línea Celular , Embrión de Mamíferos , Femenino , Expresión Génica , Humanos , Factor II del Crecimiento Similar a la Insulina/genética , Embarazo , ARN/genética , ARN/aislamiento & purificación , ARN Neoplásico/genética , ARN Neoplásico/aislamiento & purificación
3.
Obstet Gynecol ; 79(5 ( Pt 2)): 826-7, 1992 May.
Artículo en Inglés | MEDLINE | ID: mdl-1373479

RESUMEN

The introduction of sensitive assays for the beta subunit of hCG (beta-hCG) and improved ultrasound technology for diagnosis and monitoring of ectopic pregnancy have changed the clinical approach to the management of ectopic pregnancy. Only a few reports have been published of patients with ectopic gestation and negative serum beta-hCG levels. None of these described rupture of ectopic pregnancy following the decline of beta-hCG levels to below 10 mIU/mL. We describe a case of ectopic pregnancy, managed expectantly, in which rupture and hemoperitoneum occurred after the decline of beta-hCG levels to below 10 mIU/mL.


Asunto(s)
Gonadotropina Coriónica/sangre , Fragmentos de Péptidos/sangre , Embarazo Tubario/sangre , Adulto , Gonadotropina Coriónica Humana de Subunidad beta , Femenino , Hemoperitoneo/etiología , Humanos , Embarazo , Embarazo Tubario/diagnóstico , Rotura Espontánea
4.
Cancer Genet Cytogenet ; 73(1): 82-3, 1994 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8174081

RESUMEN

The association between aberrations of the human genome and the development of cancer is well established. Gene imprinting, defined as gene expression based on the gamete of origin, has previously been shown to be involved in this process by the loss of tumor suppressor gene regulation. We suggest that the activation of imprinted proto-oncogenes and growth factors may also play a vital role in tumorigenesis. Mechanistically, this can occur when the gene is removed from its imprinted sequence area, thus escaping repression. Synteny between the human and mouse genome provides the opportunity for targeted studies of imprinted genes suspected to be involved in cancer.


Asunto(s)
Regulación de la Expresión Génica , Genoma Humano , Neoplasias/genética , Animales , Cromosomas Humanos Par 22 , Cromosomas Humanos Par 9 , Genes Supresores de Tumor , Sustancias de Crecimiento/genética , Humanos , Factor II del Crecimiento Similar a la Insulina/genética , Ratones , Proto-Oncogenes/genética
5.
Fertil Steril ; 62(1): 121-5, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8005275

RESUMEN

OBJECTIVE: To evaluate the possible role for estrogen supplementation to the P luteal phase support of GnRH agonists (GnRH-a)- and hMG-induced IVF-ET cycles. SETTING: In vitro fertilization unit in a tertiary care university hospital. DESIGN: A prospectively randomized study. PATIENTS: One hundred consecutive patients undergoing ET after IVF were assigned into one of two luteal supplementation regimens. INTERVENTIONS: In all patients enrolled in the study, ovulation was induced using the midluteal regimen for pituitary down regulation with GnRH-a followed by follicular stimulation with hMG. The first group received IM P 50 mg/d, as luteal phase support, starting the day of ET. The second group received the same dosage of P, combined with oral E2 valerate, 2 mg/d. Serum levels of P and E2 were monitored every 4 days for 16 days after ET. MAIN OUTCOME MEASURES: Pregnancy rates (PRs) and live birth rates per ET. RESULTS: No significant difference in E2 or P levels throughout the cycle was observed between groups. Similar PRs per ET and the live birth rates were also observed between group A and B (28% versus 26.5% and 78.6% versus 76.1%, respectively). CONCLUSION: No advantage was found in the addition of E2 valerate to P luteal phase support of GnRH-a- and hMG-induced IVF-ET cycles.


Asunto(s)
Transferencia de Embrión , Estradiol/análogos & derivados , Fertilización In Vitro , Fase Luteínica , Progesterona/uso terapéutico , Pamoato de Triptorelina/administración & dosificación , Adulto , Quimioterapia Combinada , Estradiol/sangre , Estradiol/uso terapéutico , Femenino , Humanos , Embarazo , Resultado del Embarazo , Pamoato de Triptorelina/uso terapéutico
6.
Fertil Steril ; 62(5): 903-10, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7523201

RESUMEN

OBJECTIVES: To outline the possible role of the imprinted genes in early human embryogenesis and implantation. DATA IDENTIFICATION: Literature review. STUDY SELECTION: Studies examining the issues of genomic imprinting, implantation, gestational trophoblastic diseases, placental gene expression, and trophoblast invasion. RESULTS: Certain genes have been shown to be expressed either in the embryo or in the uterine decidua before implantation. Some of these have been shown to be parentally imprinted, that is, expressed either from their paternal or maternal origin. The paternally expressed genes are linked to placental proliferation and invasiveness. CONCLUSIONS: Clinical and basic data from different disciplines indicate that genomic imprinting may be crucial to the process of implantation.


Asunto(s)
Implantación del Embrión/genética , Impresión Genómica , Animales , Gonadotropina Coriónica/genética , Gonadotropina Coriónica Humana de Subunidad beta , Compensación de Dosificación (Genética) , Femenino , Humanos , Factor II del Crecimiento Similar a la Insulina/genética , Masculino , Fragmentos de Péptidos/genética
7.
J Soc Gynecol Investig ; 3(4): 209-15, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8796832

RESUMEN

OBJECTIVES: To define the biology of the tumor-host cell interaction with regard to cellular kinetics and morphologic changes during cell-cell interaction in an in vitro model of trophoblastic neoplasia. METHODS: Using a coculture in vitro system of cytotrophoblasts and choriocarcinoma cells, we investigated the cellular kinetics and the morphologic changes in these interacting cells. A fully automatic time-lapse image system was used to record phase contrast images of the cocultured cells in a tissue culture chamber. To examine cytoskeletal structure, immunofluorescent-labeled antibodies against intermediate filaments were used. Slides were examined with a confocal laser scanning microscope and subjected to computed analysis. RESULTS: The choriocarcinoma cells attract normal cytotrophoblasts using what resembles pseudopodia to engulf the latter cells and thus form slow-growing colonies. In this process, new hybrid cells are formed, which can be differentiated from their original contributors by morphologic characteristics. CONCLUSION: This phenomenon supports our previous biochemical and molecular data on the role of cell-cell interaction in the complex process of cytotrophoblast transformation and the development of gestational trophoblastic neoplasia.


Asunto(s)
Coriocarcinoma/patología , Placenta/citología , Neoplasias Uterinas/patología , Comunicación Celular , Línea Celular , Técnicas de Cocultivo , Citoesqueleto/ultraestructura , Femenino , Humanos , Filamentos Intermedios/ultraestructura , Cinética , Microscopía Confocal , Embarazo , Seudópodos , Trofoblastos , Células Tumorales Cultivadas
8.
Med Hypotheses ; 44(2): 116-8, 1995 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7596304

RESUMEN

The study of human evolution and the mechanism of this process can be approached from physical anthropology, which examines phenotypic expression and molecular evolution, which investigates genotypic change. Alternatively, we suggest that human evolutional process can also be explained using present day examples of abberations in evolution. Thus, from both genotypic and phenotypic perspectives, we address the question of whether Down's syndrome is an instructive example to look into the decisive role of maternal lineage in human evolution.


Asunto(s)
Síndrome de Down/genética , Filogenia , Animales , Cromosomas Humanos Par 21 , Femenino , Regulación del Desarrollo de la Expresión Génica , Hominidae/genética , Humanos , Recién Nacido , No Disyunción Genética , Embarazo , Primates/genética , Grupos Raciales/genética
9.
Eur J Gynaecol Oncol ; 23(3): 187-90, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12094951

RESUMEN

OBJECTIVES: To identify genetic and non-genetic risk factors for papillary serous uterine cancer. METHODS: A case-control study was conducted. Case women with papillary serous uterine cancer were compared with two control groups: 1) women with endometrioid uterine cancer and 2) healthy women with no past history of cancer. Cases and controls were matched for age (within two years) and ethnic group. All study subjects completed a questionnaire addressing family history. The cases and healthy controls were assessed for factors associated with estrogen exposure. RESULTS: The risks of breast cancer (RR 1.84, CI 1.03-3.31) and of prostate cancer (RR 2.21, CI 0.77-6.37) were higher among the relatives of patients with papillary serous uterine cancer, than among relatives of those with endometrioid uterine cancer. Other significant risk factors included weight at 18 years (p = 0.04) and the use of estrogen replacement therapy (p = 0.04). CONCLUSION: Relatives of women with papillary serous cancer of the uterus had an increased risk of breast and prostate cancer. Hormonal exposure also increases the risk for this cancer. These findings suggest that predisposing genetic factors, possibly related to hormone metabolism, may be common to the three forms of cancer.


Asunto(s)
Cistadenocarcinoma Papilar/epidemiología , Cistadenocarcinoma Papilar/genética , Predisposición Genética a la Enfermedad/epidemiología , Predisposición Genética a la Enfermedad/genética , Neoplasias Uterinas/epidemiología , Neoplasias Uterinas/genética , Adolescente , Adulto , Anciano , Peso Corporal , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/genética , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ontario/epidemiología , Neoplasias de la Próstata/epidemiología , Neoplasias de la Próstata/genética , Factores de Riesgo , Encuestas y Cuestionarios
10.
J Submicrosc Cytol Pathol ; 26(3): 341-6, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8087798

RESUMEN

Isolated cytotrophoblast cells from term human placenta were separated into eleven fractions according to cell size, by centrifugal elutriation. Each fraction isolated was examined by electron microscopy to elucidate ultrastructural features consistent with differences in stages of cellular differentiation. As a rule, increasing cell size correlated with evidence of progressive intracellular differentiation. This was represented by the appearance of specialization structures in later fractions, and by changes in the density of organelles and other cellular constituents. Progressive development and maturation of the rough endoplasmic reticulum was also evident. These data are the first to demonstrate successful subfractionation of the heterogeneous cytotrophoblast cell population into distinct groups, each representing different levels of cellular differentiation. These morphologic features of differentiation correlate closely with established biochemical parameters associated with various stages of intermediate cytotrophoblast cell differentiation.


Asunto(s)
Trofoblastos/citología , Trofoblastos/ultraestructura , Diferenciación Celular/fisiología , Centrifugación/métodos , Humanos , Microscopía Electrónica
11.
Harefuah ; 121(5-6): 150-3, 1991 Sep.
Artículo en Hebreo | MEDLINE | ID: mdl-1937247

RESUMEN

Abdominopelvic actinomycosis associated with the use of an intrauterine contraceptive device (IUD) is described. The diagnosis is usually made after exploratory laparotomy for severe abdominal pain and signs of an acute abdomen, or for prolonged lower abdominal pain and findings consistent with pelvic malignancy. 3 women aged 33, 44 and 52 years, respectively, are presented.


PIP: 3 cases of IUD-related abdominopelvic actinomycosis diagnosed after surgery are described. A 44-year old woman was admitted with high fever and diffused, strong abdominal pain. She had had an IUD for 4 years. Hypersensitivity all over the pelvis, an enlarged uterus, and peritoneal irritation were found upon vaginal examination. Opening the peritoneum yielded 1 liter of pus, a 6 cm diameter abscess of the right adnexa, and a myomatous uterus in 12 weeks of gestation. The uterus and the right adnexa were removed. Histology confirmed actinomycosis. Penicillin was given iv for 6 weeks, and after release she took oral penicillin for 4 more months. A 33-year old woman was admitted with high fever and excruciating pain in the lower right abdomen that had lasted on and off for months. She had had an IUD for 3 years. Vaginal examination revealed a hypersensitive uterus. enlarged right adnexa, and a firm mass between the vagina and the rectal shelf. Surgery showed the omentum attached to the sigmoid colon and the right fallopian tube with an abscess of 5 cm with cysts. The growth was resected, and the cysts were opened. She received iv erythromycin for 3 weeks and then orally for 2 months leading to full recovery. A 52-year old woman was hospitalized for hysterectomy. She had had abdominal pain radiating to the back for 1 year. She had had an IUD for 15 years. A myomatous uterus in 15 weeks of gestation was detected. Surgery revealed a 15 cm size myomatous uterus with an abscess of 6 cm around it. The uterus, the left adnexa, and the abscess were resected. Histology indicated actinomycosis. She received iv ampicillin for 1 month, and scar tissue from the abscess was treated with oral penicillin for 1 month. Cervical actinomycosis was found in 1-30% of women wearing IUDs. Diagnosis requires histopathological examination. The symptomless presence of cervical actinomycosis may require the temporary removal of the IUD and antibiotic treatment.


Asunto(s)
Abdomen , Actinomicosis/etiología , Dispositivos Intrauterinos/efectos adversos , Pelvis , Abdomen Agudo/diagnóstico , Actinomicosis/diagnóstico , Adulto , Diagnóstico Diferencial , Femenino , Humanos , Persona de Mediana Edad , Neoplasias Pélvicas/diagnóstico
16.
Baillieres Clin Obstet Gynaecol ; 12(4): 581-91, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10627769

RESUMEN

Numerous case-control, cohort studies, case reports and reviews have been published during the last 5 years regarding the association between infertility and induction of ovulation and epithelial ovarian cancer. Despite this amount of published material, final conclusions regarding direct linkage between these different aspects of infertility and ovarian cancer, as well as any data relating to a putative pathogenetic mechanism, cannot be drawn. In this review we summarize the available data as well as update a previous review by Shoham published in 1994. We outline some of the information that has become available from basic research which may help to direct investigators to suitable clinical research models that may eventually serve to clarify this enigma. Finally we share ideas that focus on specific high-risk cohorts.


Asunto(s)
Carcinoma/etiología , Infertilidad Femenina/etiología , Neoplasias Ováricas/etiología , Inducción de la Ovulación/efectos adversos , Síndrome del Ovario Poliquístico/complicaciones , Adulto , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , Fertilización In Vitro , Humanos , Persona de Mediana Edad , Factores de Riesgo
17.
Gynecol Obstet Invest ; 34(4): 243-5, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1283145

RESUMEN

Measuring beta hCG titers by either bioassay or radioimmunoassay has become the cornerstone in the management and treatment of hydatidiform mole. It is this very determination which will indicate either spontaneous remission or the need for chemotherapy treatment due to rising or plateauing titers. Herein, we report on the potential assistance of a unique ultrasonographic appearance of a hyperechogenic shadow located in the uterine wall, before and after an attempt for full evacuation of hydatidiform mole. The behavior of this echogenic area was more sensitive in predicting the course of the disease than did the beta hCG titers. Thus, using transvaginal sonography may serve as another predictor and indicator in evaluating the treatment of hydatidiform mole.


Asunto(s)
Mola Hidatiforme/diagnóstico por imagen , Recurrencia Local de Neoplasia/diagnóstico por imagen , Neoplasias Uterinas/diagnóstico por imagen , Adulto , Biomarcadores de Tumor/sangre , Gonadotropina Coriónica/sangre , Gonadotropina Coriónica Humana de Subunidad beta , Femenino , Humanos , Mola Hidatiforme/epidemiología , Recurrencia Local de Neoplasia/epidemiología , Fragmentos de Péptidos/sangre , Valor Predictivo de las Pruebas , Embarazo , Pronóstico , Ultrasonografía , Neoplasias Uterinas/epidemiología
18.
Arch Gynecol Obstet ; 251(1): 51-3, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1550391

RESUMEN

We present a case of second trimester placental separation complicated by severe bleeding diathesis. Primary fibrinogenolysis is suggested as the cause of the coagulopathy.


Asunto(s)
Trastornos de la Coagulación Sanguínea/etiología , Fibrinólisis , Enfermedades Placentarias/complicaciones , Adulto , Femenino , Humanos , Embarazo , Segundo Trimestre del Embarazo
19.
Gynecol Obstet Invest ; 33(4): 244-5, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1505816

RESUMEN

Herein, a patient being operated for cesarean section due to preterm labor in the 31st week of a triplet pregnancy induced by gonadotropins is being described. On celiotomy, peritoneal effusion was present secondary to torsion of a 10 x 6 cm right ovarian cyst. This uncommon finding contradicts the common belief that the chances for an ovarian cyst in the overcrowded peritoneal space due to a 40-week-size uterus to twist around its pedicle are remote. The possibility that preterm labor was initiated by the torsion is discussed.


Asunto(s)
Trabajo de Parto Prematuro/etiología , Síndrome de Hiperestimulación Ovárica/complicaciones , Complicaciones del Embarazo , Adulto , Cesárea , Femenino , Humanos , Trabajo de Parto Prematuro/cirugía , Síndrome de Hiperestimulación Ovárica/epidemiología , Síndrome de Hiperestimulación Ovárica/cirugía , Embarazo , Complicaciones del Embarazo/epidemiología , Complicaciones del Embarazo/cirugía , Tercer Trimestre del Embarazo , Anomalía Torsional , Trillizos
20.
Infect Dis Obstet Gynecol ; 2(1): 3-9, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-18475358

RESUMEN

OBJECTIVE: The cytokines tumor necrosis factor (TNF) and interleukin-6 (IL-6) have previously been identified in placental tissue and are known to be mediators of infection-associated induction of the host immune system. This study was undertaken to better characterize the in vitro regulation of these cytokines in cytotrophoblast cells when challenged with the bacterial product lipopolysaccharide (LPS). METHODS: Term placentas were freshly collected, digested with trypsin/DNase, and subjected to Percoll gradient centrifugation to isolate cytotrophoblasts. Either immediately or after overnight incubation, LPS (1 microg/ml) or media alone was added to the cell cultures for 0, 1, 2, 4, 8, 24, 48, and 72 h. Total cellular RNA was isolated by the guanidinium thiocyanate/cesium chloride methodology. RNA samples were run on 1% agarose-formaldehyde gels and subsequently transferred to nylon filters. Blots were hybridized with the appropriate P32-radiolabeled probe. RESULTS: In non-LPS-treated cells, minimal amounts of TNF mRNA could be detected at zero time, or throughout the incubation periods. Conversely, LPS exposure resulted in detectable signal starting at 1 h and peaking at 2 h after the addition of LPS. Overnight incubation gave stronger TNF signals in the LPS stimulated cells, although the kinetics of this response remained similar to zero time exposure. IL-6 was likewise minimally expressed at zero time, although non-stimulated cell cultures demonstrated progressive increases in mRNA expression which was maximal at 16 h after plating. LPS further augmented the transcription of IL-6 mRNA, with peak signals seen at 4 h after LPS stimulation. Again, overnight incubation of the cytotrophoblasts increased baseline and LPS-induced IL-6 mRNA responses. Long-term constant exposure of cells to LPS did not demonstrate any evidence of prolonged signaling. LPS did not alter mRNA expression of the placental gene H19 or the oncogene FOS. CONCLUSIONS: These data demonstrate the induction of TNF and IL-6 mRNA in cytotrophoblast cells with LPS. These transcriptional events are kinetically distinct and short term in nature. Overnight incubation accentuates the TNF and IL-6 mRNA signal and allows for an augmented response to LPS.

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