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1.
Arch Gynecol Obstet ; 292(4): 813-8, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25877223

RESUMEN

PURPOSE: The rise in the rate of cesarean deliveries highlights complications related to adhesion formation. This study evaluated whether the incidence and severity of adhesions secondary to repeat cesarean deliveries are a consequence of repeated surgeries or due to an individual's propensity to develop adhesions. METHODS: A retrospective chart review was conducted for 160 patients who had more than two repeat cesarean deliveries in a single teaching hospital. Data regarding intra-abdominal adhesions were collected. The severity, location, density and amount of adhesions were evaluated based on standard operative reports. Adhesion progression in subsequent cesarean deliveries was evaluated for each individual patient. RESULTS: 69/160 (43 %) patients developed significant adhesions following the primary cesarean delivery. Of these, 46 (67 %) had significant adhesions at the second surgery. Of the 91 (57 %) patients, who did not develop significant adhesions after the primary cesarean delivery, 34 (37 %) had significant adhesions at the third surgery. A patient presenting with significant adhesions at her second cesarean had a 1.88-fold risk for significant adhesions at her third cesarean (95 % CI 1.3-2.7). CONCLUSIONS: Our results suggest that adhesion development might be influenced by individual factors more than by the number of cesarean deliveries.


Asunto(s)
Cesárea Repetida/efectos adversos , Cesárea/efectos adversos , Dehiscencia de la Herida Operatoria/complicaciones , Adherencias Tisulares/etiología , Cesárea/estadística & datos numéricos , Cesárea Repetida/estadística & datos numéricos , Femenino , Humanos , Incidencia , Complicaciones Posoperatorias , Embarazo , Estudios Retrospectivos , Factores de Riesgo , Dehiscencia de la Herida Operatoria/epidemiología , Adherencias Tisulares/epidemiología
2.
Isr Med Assoc J ; 16(8): 502-5, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25269342

RESUMEN

BACKGROUND: Removal of retained placental tissue postpartum and retained products of conception (RPOC) abortion is done by uterine curettage or hysteroscopy. Trauma to the endometrium from surgical procedures, primarily curettage, can cause intrauterine adhesions (Asherman's syndrome) and subsequent infertility. The incidence of malpractice claims relating to intrauterine adhesions is rising, justifying reevaluation of the optimal way of handling these complications. OBJECTIVES: To review malpractice claims regarding intrauterine adhesions, and to explore the clinical approach that might reduce those claims or improve their medical and legal outcomes. METHODS: We examined 42 Asherman's syndrome claims handled by MCI, the largest professional liability insurer in Israel. The clinical chart of each case was reviewed and analyzed by the event preceding the adhesion formations, timing and mode of diagnosis, and outcome. We also assessed whether the adverse outcome was caused by substandard care and it it could have been avoided by different clinical practice. The legal outcome was also evaluated. RESULTS: Forty-seven percent of the cases occurred following vaginal delivery, 19% followed cesarean section, 28% were RPOC following a first-trimester pregnancy termination, and 2% followed a second-trimester pregnancy termination. CONCLUSIONS: It is apparent that due to the lack of an accepted management protocol for cases of RPOC, it is difficult to legally defend those cases when the complication of Asherman syndrome develops.


Asunto(s)
Ginatresia , Mala Praxis/estadística & datos numéricos , Procedimientos Quirúrgicos Obstétricos/efectos adversos , Obstetricia , Retención de la Placenta , Adulto , Protocolos Clínicos , Femenino , Ginatresia/etiología , Ginatresia/terapia , Humanos , Revisión de Utilización de Seguros , Israel , Responsabilidad Legal , Procedimientos Quirúrgicos Obstétricos/métodos , Obstetricia/legislación & jurisprudencia , Obstetricia/métodos , Evaluación de Resultado en la Atención de Salud , Retención de la Placenta/diagnóstico , Retención de la Placenta/terapia , Embarazo
3.
Am J Obstet Gynecol ; 206(5): 412.e1-5, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22284960

RESUMEN

OBJECTIVE: Intrauterine pressure catheter (IUPC) is the primary device used to evaluate uterine activity. In contrast to the IUPC, electrical uterine myography (EUM) enables noninvasive measurement of frequency, intensity, and tone of contractions. The aim of this study was to determine the accuracy of EUM compared to IUPC. STUDY DESIGN: EUM measured myometrial electrical activity using a multichannel amplifier and a noninvasive position sensor. In all, 47 women in labor were monitored simultaneously with an IUPC and EUM. We compared the frequency, intensity, and tone of uterine contractions between the methods. RESULTS: The correlation of the frequency, intensity, and tone of contractions between uterine electromyography and IUPC was strong with significant r values of 0.808-1 (P < .0001). CONCLUSION: Electrical uterine electromyography yields information about uterine contractility comparable to that obtained with IUPC.


Asunto(s)
Contracción Uterina/fisiología , Monitoreo Uterino/métodos , Cateterismo , Electromiografía , Femenino , Humanos , Embarazo , Presión , Estudios Prospectivos
4.
J Perinat Med ; 40(5): 539-43, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23104797

RESUMEN

OBJECTIVES: Infants with intrauterine growth restriction (IUGR) have increased morbidity and mortality. The decision whether to induce labor at term or to expectantly manage these pregnancies is controversial. The aim of this study was to assess the outcomes of these two management strategies in term pregnancies. STUDY DESIGN: This retrospective cohort study compared neonatal and maternal morbidity and mortality of IUGR fetuses (estimated fetal weight below the 10th percentile) between induced and spontaneous labors. RESULTS: Records of 669 IUGR newborns were reviewed; 499 were delivered through spontaneous labor and 170 were delivered through induced labor. Epidemiology and early perinatal outcomes between the two groups were similar. The cesarean section rate was significantly higher (P<0.005) in the induced group. CONCLUSIONS: Expectant management for term IUGR pregnancies seems to be safe, with lower rates of cesarean deliveries. A large, prospective, randomized controlled trial with long-term neonatal follow-up is indicated.


Asunto(s)
Retardo del Crecimiento Fetal/mortalidad , Trabajo de Parto Inducido , Adulto , Parto Obstétrico/estadística & datos numéricos , Femenino , Humanos , Recién Nacido , Israel/epidemiología , Embarazo , Estudios Retrospectivos , Nacimiento a Término , Adulto Joven
5.
Am J Obstet Gynecol ; 202(4): 381.e1-7, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20350645

RESUMEN

OBJECTIVE: Telomeres shorten and aggregate with cellular senescence and oxidative stress. Telomerase and its catalytic component human telomerase reverse-transcriptase regulate telomere length. The pathogenesis of preeclampsia and intrauterine growth restriction involves hypoxic stress. We aimed to assess telomere length in trophoblasts from pregnancies with those complications. STUDY DESIGN: Placental specimens from 4 groups of patients were studied: severe preeclampsia, intrauterine growth restriction, preeclampsia combined with intrauterine growth restriction, and uncomplicated (control). Telomere length and human telomerase reverse-transcriptase expression were assessed by using quantitative fluorescence-in-situ protocol and immunohistochemistry. RESULTS: Telomere length was significantly lower in preeclampsia, intrauterine growth restriction, and preeclampsia plus intrauterine growth restriction placentas. More aggregates were found in preeclampsia, but not in intrauterine growth restriction placentas. Human telomerase reverse-transcriptase was significantly higher in the controls compared with the other groups. CONCLUSION: Telomeres are shorter in placentas from preeclampsia and intrauterine growth restriction pregnancies. Increased telomere aggregate formation in preeclampsia but not in intrauterine growth restriction pregnancies, implies different placental stress-related mechanisms in preeclampsia with or without intrauterine growth restriction.


Asunto(s)
Senescencia Celular/genética , Retardo del Crecimiento Fetal/genética , Enfermedades Placentarias/genética , Preeclampsia/genética , Telómero/patología , Biopsia , Femenino , Retardo del Crecimiento Fetal/metabolismo , Retardo del Crecimiento Fetal/patología , Humanos , Inmunohistoquímica , Hibridación Fluorescente in Situ , Estrés Oxidativo , Placenta/patología , Placenta/fisiopatología , Enfermedades Placentarias/metabolismo , Enfermedades Placentarias/patología , Preeclampsia/metabolismo , Preeclampsia/patología , Embarazo , Tercer Trimestre del Embarazo , Telomerasa/genética , Telomerasa/metabolismo , Telómero/metabolismo
6.
Hereditas ; 147(2): 90-3, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20536547

RESUMEN

Telomeres are TTAGGG repetitions at the ends of chromosomes. Functioning telomeres are essential for normal segregation and maintenance of chromosomes during mitotic and meiotic divisions. Dysfunctional telomeres support the survival of aneuploid cells, a characteristic of many human malignancies. In contrast to the non-overlapping nature of telomeres in normal nuclei, telomeres of tumor nuclei tend to form aggregates. In this study, our objective was to evaluate the number of telomere aggregates (TAs) in karyotype-balanced structural rearrangements. This is an additional parameter of genetic instability, which might suggest a possible increased risk for diseases related to genomic instability, such as cancer. Twenty-six amniotic fluid cell cultures were established following genetic amniocentesis. Telomere FISH protocol was applied to the samples. Telomere aggregates were counted using a 2D microscope. The results were statistically tested by analysis of variance (ANOVA) and Kruskal-Wallis tests. More telomere aggregates in the structural balanced rearrangements were found in both study groups (balanced translocations and inversions) compared to the control group (P < 0.05). The persistence of TAs in cells is probably related to Breakage-Bridge-Fusion (BBF) cycles, a mechanism of TAs described by Muller and McClintock, resulting in end-to-end fusion that contributes to the onset of genomic instability. BBF cycles contribute to deletions, gene amplification, non-reciprocal translocations, and overall genetic changes associated with tumor genesis. According to our studies, the individuals who are carriers of balanced structural chromosomal rearrangements show some of the genetic instability parameters that appear in other circumstances, such as premalignant and malignant conditions.


Asunto(s)
Líquido Amniótico/metabolismo , Aberraciones Cromosómicas , Telómero , Hibridación Fluorescente in Situ , Cariotipificación
7.
Isr Med Assoc J ; 11(9): 542-5, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19960848

RESUMEN

BACKGROUND: Although the comprehensive evaluation of the fetal heart includes echocardiography by an experienced pediatric cardiologist, economic constraints sometimes dictate the need to select patients. OBJECTIVES: To analyze the usefulness of fetal echocardiography in the detection of congenital heart disease according to the referral indication. METHODS: This retrospective survey relates to all 3965 FE studies performed in our center from January 2000 to December 2004. The diagnosed cardiac anomalies were classified as significant and non-significant malformations. All FE studies were done by a single operator (A.L.) at Meir Medical Center, a referral center for a population of about 400,000. The 3965 FE studies were performed for the following indications: abnormal obstetric ultrasound scans, maternal and family history of cardiac malformations, medication use during the pregnancy, and maternal request. The relative risk of detecting CHD was calculated according to the various referral indications. RESULTS: Overall, 228 (5.8%) cases of CHD were found. The most common indication for referral was suspicion of CHD during a four-chamber view scan in a basic system survey or during a level II ultrasound survey. No correlation was found between maternal age and gestational age at the time of scanning and the likelihood of finding CHD. CONCLUSIONS: Our data suggest that a suspicious level II ultrasound orthe presence of polyhydramnios is an important indication for FE in the detection of significant CHD.


Asunto(s)
Ecocardiografía/métodos , Corazón Fetal/diagnóstico por imagen , Cardiopatías Congénitas/diagnóstico por imagen , Polihidramnios/diagnóstico por imagen , Adulto , Interpretación Estadística de Datos , Femenino , Edad Gestacional , Cardiopatías Congénitas/epidemiología , Cardiopatías Congénitas/genética , Humanos , Incidencia , Edad Materna , Selección de Paciente , Embarazo , Estudios Retrospectivos , Factores de Riesgo , Sensibilidad y Especificidad , Ultrasonografía Prenatal
8.
Cancer Genet Cytogenet ; 180(1): 20-3, 2008 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-18068528

RESUMEN

Hepatitis C virus (HCV) has been recently recognized as a potential cause of B-cell lymphoma. Both chronic hepatitis B and C with or without cirrhosis represent major preneoplastic conditions, and the majority of hepatocellular carcinomas arise in these pathological settings. According to the aneuploidy-cancer theory, carcinogenesis is initiated by random aneuploidy, which is either induced by carcinogens or arises spontaneously. The aim of this study was to evaluate random aneuploidy rate in HCV patients during chronic infection and remission (past infection eradicated), compared with non-Hodgkin lymphoma (NHL) patients and healthy controls. To determine random aneuploidy, we applied the FISH technique with probes for chromosomes 9 and 18. Significantly higher random aneuploidy rate was found in the HCV-infected and lymphoma patients than in the control group; the past HCV group in remission had intermediate rates, between those of the control group and the chronically infected patients. Patients who have eradicated HCV infection may nonetheless carry higher risk for future malignancy and therefore need long-term follow-up.


Asunto(s)
Aneuploidia , Hepatitis C Crónica/genética , Linfoma no Hodgkin/genética , Anciano , Estudios de Casos y Controles , Cromosomas Humanos Par 18 , Cromosomas Humanos Par 9 , Hepatitis C Crónica/tratamiento farmacológico , Humanos , Persona de Mediana Edad , Riesgo
9.
J Matern Fetal Neonatal Med ; 18(1): 77-9, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16105796

RESUMEN

A 33-year-old healthy woman, gravida 1 with twins pregnancy was admitted with mild preeclampsia and unusual hyponatremia which resolved promptly postpartum. This is the seventh reported case of hyponatremia complicating preeclampsia, four of the patients carried twins and four had nephrotic syndrome.


Asunto(s)
Hiponatremia/complicaciones , Preeclampsia/sangre , Complicaciones del Embarazo/sangre , Adulto , Femenino , Humanos , Embarazo , Resultado del Embarazo , Embarazo Múltiple , Sodio/sangre , Gemelos
10.
Int J Gynaecol Obstet ; 129(1): 13-6, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25585859

RESUMEN

OBJECTIVE: To evaluate whether carriers of group B streptococcus (GBS) have adverse obstetric and neonatal outcomes when preterm premature rupture of membranes (PPROM) occurs. METHODS: In a retrospective study, data were reviewed for women with a singleton pregnancy and PPROM before 34 weeks who attended the Meir Medical Center, Kfar Saba, Israel, between 2005 and 2012. All women received roxithromycin for 1 week, and ampicillin until GBS culture results were available. Ampicillin was continued to 1 week if the GBS culture was positive. The primary study outcome measure was the latency period (time from rupture of membranes to active/induced labor). RESULTS: Among 116 eligible patients, 21 (18.1%) were GBS carriers and 95 (81.9%) noncarriers. The latency period was 11.2 ± 18.1 days for GBS carriers versus 7.5 ± 9.6 days for noncarriers (P=0.93). However, there was a correlation between the length of ampicillin treatment and the latency period (Spearman correlation coefficient 0.7; P<0.001). There were no differences in early neonatal outcomes. CONCLUSION: GBS carriers with PPROM did not have adverse outcomes. Longer treatment with ampicillin among GBS carriers prolonged the latency period.


Asunto(s)
Antibacterianos/administración & dosificación , Profilaxis Antibiótica/estadística & datos numéricos , Rotura Prematura de Membranas Fetales/microbiología , Trabajo de Parto/efectos de los fármacos , Streptococcus agalactiae/efectos de los fármacos , Adulto , Ampicilina/administración & dosificación , Portador Sano , Femenino , Humanos , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Embarazo , Complicaciones Infecciosas del Embarazo/microbiología , Complicaciones Infecciosas del Embarazo/prevención & control , Resultado del Embarazo , Estudios Retrospectivos , Roxitromicina/administración & dosificación , Infecciones Estreptocócicas/prevención & control , Infecciones Estreptocócicas/transmisión
11.
Cancer Genet Cytogenet ; 133(1): 34-8, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11890987

RESUMEN

The replication status of malignant cells is usually asynchronous. However, to date the pattern of replication has not been studied in myeloproliferative disorders nor has the effect of chemotherapy been systematically evaluated. Therefore, we used fluorescence in situ hybridization to interphase nuclei in PHA-stimulated peripheral blood lymphocytes to examine replication timing of three alleles associated with the malignant process. The study group comprised hydroxyurea treated and untreated patients with essential thrombocytosis (ET) or polycythemia vera (PV). A significantly higher rate of the asynchronous pattern of replication in both treated and untreated patients was found as compared to healthy controls. The highest rate of asynchronous replication was observed in untreated patients. Also, the frequency of the two doublets pattern was significantly higher in the untreated group compared to the treated patients and to the control groups. In conclusion, patients with PV and ET have a higher rate of asynchronous pattern of replication. A possible correlation between disease activity and the pattern of replication is suggested. The effect of hydroxyurea on the pattern of replication is variable.


Asunto(s)
Replicación del ADN , Leucocitos/patología , Policitemia Vera/patología , Trombocitosis/patología , Adulto , Anciano , Antidrepanocíticos/farmacología , Antidrepanocíticos/uso terapéutico , Recuento de Células , División Celular/efectos de los fármacos , Replicación del ADN/efectos de los fármacos , Femenino , Humanos , Hidroxiurea/farmacología , Hidroxiurea/uso terapéutico , Leucocitos/efectos de los fármacos , Masculino , Persona de Mediana Edad , Inhibidores de la Síntesis del Ácido Nucleico/farmacología , Inhibidores de la Síntesis del Ácido Nucleico/uso terapéutico , Policitemia Vera/tratamiento farmacológico , Trombocitosis/tratamiento farmacológico
12.
Isr Med Assoc J ; 4(9): 702-5, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12440235

RESUMEN

BACKGROUND: While most allelic pairs of DNA replicate synchronously during the S phase of the cell cycle, some genes normally replicate asynchronously, i.e., genes on the X chromosome and imprinted genes. The replication control mechanism is unknown but was shown to be impaired in malignancies and chromosomal trisomies where replication pattern becomes asynchronous. OBJECTIVES: To determine the level of asynchronization in replication timing of cells from patients with microdeleted genomes. METHODS: We applied monocolor fluorescent in situ hybridization with different probes on leukocytes from microdeleted genomes. RESULTS: All samples derived from the microdeleted genomes showed significantly higher levels of an asynchronized pattern compared to normal individuals. CONCLUSIONS: Even a "small" genetic imbalance (microdeletion) can interfere with gene replication and cell cycle progression, as previously shown in full trisomies.


Asunto(s)
Desequilibrio Alélico/genética , Replicación del ADN/genética , Eliminación de Gen , Genoma Humano , Cromosomas Humanos 21-22 e Y/genética , Genes myc/genética , Genes p53/genética , Humanos , Hibridación Fluorescente in Situ , Leucocitos/fisiología , Técnicas de Sonda Molecular , Proteína de Retinoblastoma/genética , Fase S/genética
13.
Early Hum Dev ; 90(9): 465-9, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25010904

RESUMEN

INTRODUCTION: Placentas from pregnancies complicated with IUGR (intrauterine growth restriction) express altered telomere homeostasis. In the current study, we examined mechanisms of telomere shortening in these placentas. METHODS: Placental biopsies from 15 IUGR and 15 healthy control pregnancies were examined. The percentage of trophoblasts with fragmented nuclei: senescence-associated heterochromatin foci (SAHF), was calculated using DAPI staining. The amount of human telomerase reverse transcriptase (hTERT) mRNA was evaluated using RtPCR levels of telomere capture using FISH in those samples were estimated. RESULTS: The percentage of trophoblasts with SAHF was higher in IUGR compared to control samples, (25±13.4% vs. 1.6±1.6%, P<0.0001), hTERT mRNA was decreased (0.5±0.2 vs. 0.9±0.1, P<0.0001) and telomere capture was increased (13.2±9.7% vs.1.3±2.5%, P<0.001). CONCLUSIONS: We suggest that IUGR placentas express increased signs of senescence as part of the impaired telomere homeostasis. One factor that mediates telomere shortening in these placentas is decreased hTERT mRNA, leading to decreased protein expression and therefore, reduced telomere elongation. Telomere capture, which is a healing process, is increased in IUGR trophoblasts as a compensatory mechanism.


Asunto(s)
Retardo del Crecimiento Fetal/genética , Acortamiento del Telómero , Estudios de Casos y Controles , Femenino , Retardo del Crecimiento Fetal/patología , Homeostasis , Humanos , Hibridación Fluorescente in Situ , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
14.
J Matern Fetal Neonatal Med ; 26(11): 1086-9, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23339291

RESUMEN

OBJECTIVE: Senescence has been described as a stable cell proliferation arrest resulting from the progression of primary human fibroblasts through a finite number of population doublings in vitro. Accelerated telomere shortening was observed in pregnancies complicated by intrauterine growth restriction, in placentas of diabetic mothers and trisomy 21 amniocytes. We hypothesized that under conditions of stress, telomeres in placentas will be shorter and there will be more cells with the senescence phenotype. METHODS: The two study groups included placental biopsies from 7 cases of trisomy 21 and amniocytes from 10 cases of trisomy 21. The control groups consisted of placental biopsies from 6 cases and amniocytes from 10 pregnancies with a normal karyotype. The samples were analyzed for the presence of senescent cells based on the number of fragments in each cell. RESULTS: A significantly higher percentage of cells in the senescent state, based on a higher percentage of cells with more fragmentations, were found in the amniocytes (20.8%) and in trophoblasts (94.3%) from placentas with trisomy 21 compared to the control groups. CONCLUSION: Among other genetic instability parameters, trisomy 21 amniocytes and trophoblasts express a higher prevalence of senescent cells than were previously reported.


Asunto(s)
Amnios/fisiopatología , Senescencia Celular/fisiología , Síndrome de Down/fisiopatología , Placenta/fisiopatología , Amnios/patología , Estudios de Casos y Controles , Células Cultivadas , Análisis Citogenético , Síndrome de Down/genética , Síndrome de Down/patología , Femenino , Heterocromatina/metabolismo , Humanos , Placenta/patología , Embarazo , Trofoblastos/patología , Trofoblastos/fisiología
15.
J Matern Fetal Neonatal Med ; 25(12): 2625-8, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22877079

RESUMEN

OBJECTIVE: Fetal cells represented by extravillous trophoblasts (EVT) obtained from the cervix by a minimally invasive procedure are important for prenatal diagnosis in early pregnancies. Endoreduplication is a duplication of chromosomes without mitosis, leading to polyploidy that might represent increased cellular metabolic activity. In this study, we estimated the normal prevalence of polyploid trophoblasts exfoliated to the cervix between 5 and 13 weeks of gestation. METHODS: Cervical samples were obtained by cytobrush, between 5 and 13 weeks of gestation from 36 randomly selected, singleton pregnancies. FISH was done with X, Y and two 21 probes. RESULTS: We diagnosed 21 pregnancies with female and 15 pregnancies with male fetal karyotypes. A mean of 15.2 (0.02%) tetraploid cells were found in pregnancies with a female fetus and a mean of 2.0 (0.003%) tetraploid cells were found in pregnancies with a male fetus. The tetraploid cells (endoreduplicated trophoblasts) were two to three times larger than the normal cells usually seen in the cervix. CONCLUSIONS: Extravillus trophoblasts tend to form endoreduplication to the ploidy level of 4c-8c of DNA. Those cells may represent a typical phenomenon in the growing placenta. Extravillus trophoblasts from female fetuses tend to form higher rates of endoreduplication.


Asunto(s)
Cuello del Útero/metabolismo , Endorreduplicación/fisiología , Embarazo/genética , Trofoblastos/metabolismo , Cuello del Útero/citología , Muestra de la Vellosidad Coriónica , Reacciones Falso Positivas , Femenino , Salud , Humanos , Recién Nacido , Cariotipificación/métodos , Masculino , Poliploidía , Embarazo/metabolismo , Primer Trimestre del Embarazo/genética , Primer Trimestre del Embarazo/metabolismo , Diagnóstico Prenatal/métodos , Trofoblastos/citología , Trofoblastos/fisiología , Estudios de Validación como Asunto
16.
Early Hum Dev ; 87(2): 73-5, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21168289

RESUMEN

INTRODUCTION: intrauterine growth restriction (IUGR) is a significant cause of both short- and long-term morbidity and mortality. IUGR secondary to placental dysfunction is correlated with telomere shortening. Telomerase is an enzyme complex that elongates telomeres. One of its components is encoded by the telomerase RNA component gene (TERC), which serves as the RNA template for the addition of telomeric repeats. We hypothesized decreased TERC gene copy number in IUGR placentas as part of the mechanism of telomere shortening in placental dysfunction. METHODS: we estimated the gene copy number of the TERC gene at 3q26 by applying FISH to trophoblasts of placental biopsies from five pregnancies with IUGR caused by placental insufficiency and compared them to placentas from five gestational-age matched, uncomplicated pregnancies. RESULTS: significantly lower TERC gene copy number was observed in IUGR trophoblasts on the same chromosome and on other chromosomes, compared to the control samples (p<0.05). CONCLUSIONS: the TERC gene copy number is decreased in IUGR trophoblasts. These results support the observations of telomere shortening and decreased telomerase activity in IUGR placentas. We suggest that these findings might play a role in the pathophysiology of IUGR, perhaps by promoting senescence in trophoblasts of IUGR placentas.


Asunto(s)
Retardo del Crecimiento Fetal/genética , Dosificación de Gen , Placenta/metabolismo , ARN/genética , Telomerasa/genética , Estudios de Casos y Controles , Cromosomas Humanos Par 3 , Femenino , Retardo del Crecimiento Fetal/metabolismo , Dosificación de Gen/fisiología , Edad Gestacional , Humanos , Hibridación Fluorescente in Situ , Embarazo , Subunidades de Proteína/genética , Subunidades de Proteína/metabolismo , ARN/metabolismo , Telomerasa/metabolismo , Trofoblastos/metabolismo
17.
Early Hum Dev ; 86(7): 451-6, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20619976

RESUMEN

OBJECTIVE: Telomeres are nucleoprotein structures located at the termini of chromosomes, and protect them from fusion and degradation. Telomeres are progressively shortened with each mitotic cycle and by environmental factors. We hypothesized that antepartum stress can lead to accelerated telomere shortening in placental trophoblasts, and plays a role in intrauterine growth restriction (IUGR). METHODS: Placental biopsies were derived from 16 pregnancies complicated with IUGR and from 13 uncomplicated pregnancies. Fluorescence-in-situ protocol was used to determine telomere length. Immunohistochemistry for hTERT was performed to assess telomerase activity. Clinical and histopathological characteristics were collected to ensure that IUGR was secondary to placental insufficiency. Fluorescence-in-situ-hybridization was used to rule out aneuploidy as a reason for shortened telomeres. RESULTS: The number and intensity of telomeres staining and telomerase activity were significantly lower in the IUGR placentas. No aneuploidy was detected for the chromosomes checked in the placental biopsies. CONCLUSIONS: Telomeres are shorter in trophoblasts of IUGR placentas.


Asunto(s)
Retardo del Crecimiento Fetal/genética , Insuficiencia Placentaria/genética , Telómero/ultraestructura , Trofoblastos/ultraestructura , Femenino , Retardo del Crecimiento Fetal/etiología , Humanos , Inmunohistoquímica , Hibridación Fluorescente in Situ , Embarazo
19.
Cancer Genet Cytogenet ; 191(2): 63-6, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19446739

RESUMEN

Broken chromosomes can acquire new telomeres by "telomere capture" (TC), and it has become possible to investigate the terminus in cytogenetically visible telomere rearrangements. The TC phenomenon was observed in malignant conditions. We evaluated the TC rate in hepatitis C virus (HCV) patients compared to non-Hodgkin's lymphoma patients, as well as relative to a control group. For this purpose, we used two Cytocell probes, 15qter and 13qter. Higher TC rates were found in the three study groups relative to the control group. Our results showed that HCV patients have some of the components that can initiate the cascade of events leading to malignancies.


Asunto(s)
Inestabilidad Cromosómica/genética , Hepatitis C/patología , Linfoma no Hodgkin/patología , Telómero/genética , Telómero/patología , Técnicas de Cultivo de Célula , Cromosomas Humanos , Hepatitis C/genética , Hepatitis C Crónica/genética , Hepatitis C Crónica/patología , Humanos , Hibridación Fluorescente in Situ , Linfocitos/citología , Linfocitos/patología , Linfoma no Hodgkin/genética , Recombinación Genética , Valores de Referencia , Translocación Genética
20.
J Hum Genet ; 51(6): 541-547, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16683054

RESUMEN

Down syndrome (DS) is a multifactorial disorder with a high predisposition to leukemia and other malignancies. A change in the replication pattern from synchronous in normal genes to asynchronous in DS amniocytes has previously been reported. The objective of this study was to evaluate additional molecular cytogenetic factors which could re-emphasize the high correlation between DS cells and genetic instability. We found a higher rate of random aneuploidy in chromosomes 9 and 18 and a higher rate of asynchronous replication in the subtelomeric region or DS leukocytes than in cells from normal newborns. In addition, the telomere capture phenomenon was observed in the DS leukocytes but not in normal controls. The molecular cytogenetic factors observed in the DS individuals are known to correlate with genomic instability and with predisposition to cancer.


Asunto(s)
Síndrome de Down/genética , Aneuploidia , Inestabilidad Cromosómica , Cromosomas Humanos Par 13/genética , Cromosomas Humanos Par 15/genética , Cromosomas Humanos Par 18/genética , Cromosomas Humanos Par 9/genética , Citogenética , Replicación del ADN/genética , Síndrome de Down/complicaciones , Inestabilidad Genómica , Humanos , Hibridación Fluorescente in Situ , Lactante , Recién Nacido , Biología Molecular , Neoplasias/etiología , Neoplasias/genética , Telómero/genética , Trisomía
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