Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 22
Filtrar
Más filtros











Base de datos
Intervalo de año de publicación
1.
Hum Reprod ; 36(11): 2992-3002, 2021 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-34568940

RESUMEN

STUDY QUESTION: How are germ cell numbers and initiation of folliculogenesis affected in fetal Turner syndrome (TS) ovaries? SUMMARY ANSWER: Germ cell development was severely affected already in early second trimester pregnancies, including accelerated oogonia loss and impaired initiation of primordial follicle formation in TS ovaries, while the phenotype in TS mosaic ovaries was less severe. WHAT IS KNOWN ALREADY: Females with TS are characterized by premature ovarian insufficiency (POI). This phenotype is proposed to be a consequence of germ cell loss during development, but the timing and mechanisms behind this are not characterized in detail. Only few studies have evaluated germ cell development in fetal TS and TS mosaic ovaries, and with a sparse number of specimens included per study. STUDY DESIGN, SIZE, DURATION: This study included a total of 102 formalin-fixed and paraffin-embedded fetal ovarian tissue specimens. Specimens included were from fetuses with 45,X (N = 42 aged gestational week (GW) 12-20, except one GW 40 sample), 45,X/46,XX (N = 7, aged GW 12-20), and from controls (N = 53, aged GW 12-42) from a biobank (ethics approval # H-2-2014-103). PARTICIPANTS/MATERIALS, SETTING, METHODS: The number of OCT4 positive germ cells/mm2, follicles (primordial and primary)/mm2 and cPARP positive cells/mm2 were quantified in fetal ovarian tissue from TS, TS mosaic and controls following morphological and immunohistochemical analysis. MAIN RESULTS AND THE ROLE OF CHANCE: After adjusting for gestational age, the number of OCT4+ oogonia was significantly higher in control ovaries (N = 53) versus 45,X ovaries (N = 40, P < 0.001), as well as in control ovaries versus 45,X/46,XX mosaic ovaries (N = 7, P < 0.043). Accordingly, the numbers of follicles were significantly higher in control ovaries versus 45,X and 45,X/46,XX ovaries from GW 16-20 with a median range of 154 (N = 11) versus 0 (N = 24) versus 3 (N = 5) (P < 0.001 and P < 0.015, respectively). The number of follicles was also significantly higher in 45,X/46,XX mosaic ovaries from GW 16-20 compared with 45,X ovaries (P < 0.005). Additionally, the numbers of apoptotic cells determined as cPARP+ cells/mm2 were significantly higher in ovaries 45,X (n = 39) versus controls (n = 15, P = 0.001) from GW 12-20 after adjusting for GW. LIMITATIONS, REASONS FOR CAUTION: The analysis of OCT4+ cells/mm2, cPARP+ cells/mm2 and follicles (primordial and primary)/mm2 should be considered semi-quantitative as it was not possible to use quantification by stereology. The heterogeneous distribution of follicles in the ovarian cortex warrants a cautious interpretation of the exact quantitative numbers reported. Moreover, only one 45,X specimen and no 45,X/46,XX specimens aged above GW 20 were available for this study, which unfortunately made it impossible to assess whether the ovarian folliculogenesis was delayed or absent in the TS and TS mosaic specimens. WIDER IMPLICATIONS OF THE FINDINGS: This human study provides insights about the timing of accelerated fetal germ cell loss in TS. Knowledge about the biological mechanism of POI in girls with TS is clinically useful when counseling patients about expected ovarian function and fertility preservation strategies. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC). TRIAL REGISTRATION NUMBER: N/A.


Asunto(s)
Oogonios , Síndrome de Turner , Anciano , Femenino , Desarrollo Fetal , Humanos , Masculino , Folículo Ovárico , Ovario , Embarazo , Síndrome de Turner/genética
2.
Hum Mol Genet ; 27(3): 430-439, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29186436

RESUMEN

In humans, the most common sex chromosomal disorder is Klinefelter syndrome (KS), caused by the presence of one or more extra X-chromosomes. KS patients display a varying adult phenotype but usually present with azoospermia due to testicular degeneration, which accelerates at puberty. The timing of the germ cell loss and whether it is caused by dysgenetic fetal development of the testes is not known. We investigated eight fetal KS testes and found a marked reduction in MAGE-A4-positive pre-spermatogonia compared with testes from 15 age-matched controls, indicating a failure of the gonocytes to differentiate into pre-spermatogonia. Transcriptome analysis by RNA-sequencing of formalin-fixed, paraffin-embedded testes originating from four fetal KS and five age-matched controls revealed 211 differentially expressed transcripts in the fetal KS testis. We found a significant enrichment of upregulated X-chromosomal transcripts and validated the expression of the pseudoautosomal region 1 (PAR1) gene, AKAP17A. Moreover, we found enrichment of long non-coding RNAs in the KS testes (e.g. LINC01569 and RP11-485F13.1). In conclusion, our data indicate that the testicular phenotype observed among adult men with KS is initiated already in fetal life by failure of the gonocyte differentiation into pre-spermatogonia, which could be due to aberrant expression of long non-coding RNAs.


Asunto(s)
Perfilación de la Expresión Génica/métodos , Síndrome de Klinefelter/genética , ARN Largo no Codificante/genética , Testículo/metabolismo , Adolescente , Adulto , Antígenos/genética , Células Germinativas/metabolismo , Humanos , Masculino , Glicoproteínas de Membrana/genética , Maduración Sexual , Espermatogénesis/genética , Espermatogonias/metabolismo , Adulto Joven
3.
Acta Paediatr ; 106(5): 779-785, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28135773

RESUMEN

AIM: Germ cell tumours (GCTs) are a rare heterogeneous tumour group derived from primordial germ cells, which can be benign or malignant and occur in the gonads or extragonadally. This study mapped the paediatric GCTs in Denmark from 1984 to 2013 to study the incidence and outcome. METHODS: We identified paediatric GCTs from the Danish Childhood Cancer and National Pathology Registries and reviewed the case records for patient characteristics, tumour characteristics and clinical outcome. RESULTS: We identified 403 (71% female) paediatric GCTs and the crude incidence was 1.43 per 100 000. Of these, 79 (20%) were malignant, 39 (10%) were potentially malignant and 285 (70%) were benign. Extragonadal GCTs (39%) were mainly observed in early childhood and were predominately sacrococcygeal teratomas. Gonadal GCTs (61%) in late childhood were most frequently mature teratomas in the ovaries. Nearly all patients underwent surgery. Of the malignant tumours, 62% were treated with chemotherapy. Radiotherapy was only administered to intracranial GCTs. In the cohort, 12 patients died (3%). CONCLUSION: Paediatric GCTs in Denmark were mainly benign and mortality was low, even for malignant tumours. We identified a peak of extragonadal GCTs in early childhood and a peak of gonadal GCTs in late childhood, which was comparable to previous reports.


Asunto(s)
Neoplasias de las Glándulas Endocrinas/mortalidad , Neoplasias de Células Germinales y Embrionarias/mortalidad , Adolescente , Niño , Preescolar , Dinamarca/epidemiología , Neoplasias de las Glándulas Endocrinas/terapia , Femenino , Humanos , Incidencia , Lactante , Masculino , Neoplasias de Células Germinales y Embrionarias/terapia
4.
Int J Dev Biol ; 57(2-4): 141-51, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23784824

RESUMEN

Observations in patients with an activating mutation of fibroblast growth factor receptor 3 (FGFR3) suggest a role for FGFR3 signalling in promoting proliferation or survival of germ cells. In this study, we aimed to identify the FGFR3 subtype and the ontogeny of expression during human testis development and to ascertain whether FGFR3 signalling is linked to germ cell proliferation and the pathogenesis of testicular germ cell tumours (TGCTs) of young adult men. Using RT-PCR, immunohistochemistry and Western blotting, we examined 58 specimens of human testes throughout development for FGFR3 expression, and then compared expression of FGFR3 with proliferation markers (PCNA or Ki67). We also analysed for FGFR3 expression 30 TGCTs and 28 testes containing the tumour precursor cell, carcinoma in situ (CIS). Fetal and adult testes expressed exclusively the FGFR3IIIc isoform. FGFR3 protein expression was restricted to the cytoplasm/plasma membrane of spermatogonia and was most prevalent at mid-gestation, infancy and from puberty onwards. Phosphorylated (p)FGFR was detected in pre-spermatogonia at mid-gestation and in spermatogonia during puberty and in the adult testis. Throughout normal human testis development, expression of FGFR3 did not directly correlate with proliferation markers. In preinvasive CIS cells and in TGCTs, including classical seminoma and embryonal carcinoma, FGFR3IIIc was detected only in a small number of cells, with a heterogeneous expression pattern. FGFR3 is an excellent marker for human pre-/spermatogonia throughout development. Signalling through this receptor is likely associated with spermatogonial survival rather than proliferation. FGFR3 is not expressed in gonocytes and may not be essential to the aetiology of TGCTs stemming from CIS.


Asunto(s)
Carcinoma in Situ/metabolismo , Proliferación Celular , Feto/metabolismo , Regulación del Desarrollo de la Expresión Génica , Neoplasias de Células Germinales y Embrionarias/metabolismo , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos/metabolismo , Neoplasias Testiculares/metabolismo , Testículo/metabolismo , Adolescente , Adulto , Western Blotting , Carcinoma in Situ/genética , Carcinoma in Situ/patología , Diferenciación Celular , Niño , Preescolar , Feto/citología , Humanos , Técnicas para Inmunoenzimas , Lactante , Recién Nacido , Antígeno Ki-67/genética , Antígeno Ki-67/metabolismo , Masculino , Neoplasias de Células Germinales y Embrionarias/genética , Neoplasias de Células Germinales y Embrionarias/patología , Fosforilación , Antígeno Nuclear de Célula en Proliferación/genética , Antígeno Nuclear de Célula en Proliferación/metabolismo , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Neoplasias Testiculares/genética , Neoplasias Testiculares/patología , Testículo/citología , Adulto Joven
5.
Mol Hum Reprod ; 18(11): 523-34, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22899867

RESUMEN

The mitosis-meiosis switch is a key event in the differentiation of germ cells. In humans, meiosis is initiated in fetal ovaries, whereas in testes meiotic entry is inhibited until puberty. The purpose of this study was to examine the expression pattern of meiosis regulators in human gonads and to investigate a possible role of DMRT1 in the regulation of meiotic entry. The expression pattern of DMRT1, STRA8, SCP3, DMC1, NANOS3, CYP26B1 and NANOS2 was investigated by RT-PCR and immunohistochemistry in a series of human testis samples from fetal life to adulthood, and in fetal ovaries. DMRT1 was expressed in testes throughout development but with marked spatio-temporal changes. At the early fetal period of 8-20 gestational weeks (GW) and at infantile mini-puberty, DMRT1 was predominantly expressed in Sertoli cells, whereas at later stages of gestation (22-40 GW), during childhood and in post-pubertal testes, DMRT1 was most abundant in spermatogonia, except in the A-dark type. In fetal ovaries, DMRT1 was detected in oogonia and oocytes until 20 GW, but was completely down-regulated following meiotic entry. STRA8, SCP3 and DMC1 were expressed mainly in oocytes and spermatogonia in accordance with their role in initiation and progression of meiosis. The putative meiosis inhibitors, CYP26B1 and NANOS2, were primarily expressed in Leydig cells and spermatocytes, respectively. In conclusion, the expression pattern of the investigated meiotic regulators is largely conserved in the human gonads compared with rodents, but with some minor differences, such as a stable expression of CYP26B1 in human fetal ovaries. The sexually dimorphic expression pattern of DMRT1 indicates a similar role in the mitosis-meiosis switch in human gonads as previously demonstrated in mice. The biological importance of the changes in expression of DMRT1 in Sertoli cells remains to be established, but it is consistent with DMRT1 reinforcing the inhibition of meiosis in the testis.


Asunto(s)
Sistema Enzimático del Citocromo P-450/genética , Meiosis/genética , Ovario/metabolismo , Testículo/metabolismo , Factores de Transcripción/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Femenino , Feto , Regulación del Desarrollo de la Expresión Génica , Edad Gestacional , Humanos , Células Intersticiales del Testículo/metabolismo , Masculino , Mitosis/genética , Oocitos/metabolismo , Oogonios/metabolismo , Especificidad de Órganos , Ovario/embriología , Ovario/crecimiento & desarrollo , Ácido Retinoico 4-Hidroxilasa , Células de Sertoli/metabolismo , Caracteres Sexuales , Espermatocitos/metabolismo , Espermatogonias/metabolismo , Testículo/embriología , Testículo/crecimiento & desarrollo , Factores de Transcripción/metabolismo
6.
Acta Obstet Gynecol Scand ; 91(3): 386-90, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22122607

RESUMEN

We evaluated the correlation between prenatal diagnosis by ultrasound and autopsy findings, based on 52 second-trimester pregnancies terminated due to fetal malformations or chromosome aberrations diagnosed at a gestational age of 12-25 weeks. In 24 pregnancies, there was full agreement between ultrasound and autopsy. In 23 fetuses, the main diagnosis was confirmed and additional or more specific findings were observed on autopsy. In five fetuses, there were considerable differences. Discrepancies between ultrasound and autopsy findings were mainly anomalies undetectable by ultrasound and thus expected; however, about one-third of the discrepancies were not expected, representing findings that were 'missed' at ultrasound. The main ultrasound diagnoses were confirmed in the majority of the pregnancies, but the additional information obtained at autopsy in more than half of the fetuses clearly shows the value and benefit of postmortem fetal examination following termination of a pregnancy.


Asunto(s)
Aborto Eugénico , Autopsia , Aberraciones Cromosómicas , Anomalías Congénitas/diagnóstico , Ultrasonografía Prenatal , Adulto , Anomalías Congénitas/diagnóstico por imagen , Anomalías Congénitas/genética , Femenino , Humanos , Embarazo , Segundo Trimestre del Embarazo , Reproducibilidad de los Resultados , Estudios Retrospectivos
7.
J Pathol ; 224(4): 473-83, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21706474

RESUMEN

Spermatocytic seminoma (SS) is a rare testicular neoplasm that occurs predominantly in older men. In this study, we aimed to shed light on the histogenesis of SS by investigating the developmental expression of protein markers that identify distinct subpopulations of human spermatogonia in the normal adult testis. We analysed the expression pattern of OCT2, SSX2-4, and SAGE1 in 36 SS cases and four intratubular SS (ISS) as well as a series of normal testis samples throughout development. We describe for the first time two different types of SS characterized by OCT2 or SSX2-4 immunoexpression. These findings are consistent with the mutually exclusive antigenic profile of these markers during different stages of testicular development and in the normal adult testis. OCT2 was expressed predominantly in A(dark) spermatogonia, SSX2-4 was present in A(pale) and B spermatogonia and leptotene spermatocytes, whilst SAGE1 was exclusively present in a subset of post-pubertal germ cells, most likely B spermatogonia. The presence of OCT2 and SSX2-4 in distinct subsets of germ cells implies that these markers represent germ cells at different maturation stages. Analysis of SAGE1 and SSX2-4 in ISS showed spatial differences suggesting ongoing maturation of germ cells during progression of SS tumourigenesis. We conclude that the expression pattern of OCT2, SSX2-4, and SAGE1 supports the origin of SS from spermatogonia and provides new evidence for heterogeneity of this tumour, potentially linked either to the cellular origin of SS or to partial differentiation during tumour progression, including a hitherto unknown OCT2-positive variant of the tumour likely derived from A(dark) spermatogonia.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Seminoma/metabolismo , Espermatogonias/metabolismo , Neoplasias Testiculares/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Antígenos de Neoplasias/metabolismo , Preescolar , Análisis Mutacional de ADN/métodos , ADN de Neoplasias/genética , Progresión de la Enfermedad , Humanos , Lactante , Masculino , Persona de Mediana Edad , Mutación , Proteínas de Neoplasias/metabolismo , Proteínas de Transporte de Catión Orgánico/metabolismo , Transportador 2 de Cátion Orgánico , Proteínas Proto-Oncogénicas p21(ras)/genética , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos/genética , Proteínas Represoras/metabolismo , Seminoma/genética , Seminoma/patología , Espermatogonias/patología , Neoplasias Testiculares/genética , Neoplasias Testiculares/patología , Testículo/crecimiento & desarrollo , Testículo/metabolismo
8.
APMIS ; 119(4-5): 259-62, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21492225

RESUMEN

During a 1-year period 4785 intraoperative consultations were performed. The pathology reports were retrospectively reviewed to determine the accuracy of frozen section diagnosis in various tissue types. Skin for evaluation of section margins and axillary sentinel lymph nodes for evaluation of metastatic disease were most frequently sent for frozen section diagnosis. The number of discordant cases were 182, 178 were false negative and four were false positive. When frozen section diagnoses were compared with permanent section diagnoses, the overall diagnostic concordance was 95.1%. The number of deferred specimens was 57. The accuracy of frozen section diagnosis varied between tissue types, and axillary sentinel lymph nodes accounted for the greatest number of discordances. In conclusion, the frozen section diagnosis is a reliable method with varying concordance and deferral rates between tissue types. We suggest regular monitoring of the performance in frozen section diagnosis.


Asunto(s)
Secciones por Congelación/estadística & datos numéricos , Dinamarca , Reacciones Falso Negativas , Reacciones Falso Positivas , Femenino , Humanos , Periodo Intraoperatorio , Masculino , Servicio de Patología en Hospital , Reproducibilidad de los Resultados , Estudios Retrospectivos
9.
Dev Neurosci ; 32(2): 149-62, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20523026

RESUMEN

The development of the human neocortex is a complex and highly regulated process involving a time-related expression of many transcription factors including the homeobox genes Pax6 and Meis2. During early development, Pax6 is expressed in nuclei of radial glia cells in the neocortical proliferative zones and controls the differentiation and neurogenetic fate of these cells in the dorsal telencephalon in rodents. Animal studies on the Meis2 gene have revealed expression in the developing telencephalon and Meis2 is known to regulate the expression of Pax6 in the eye and pancreas. Because of this functional relation between Pax6 and Meis2, we studied the spatial and temporal expression of PAX6, and MEIS2 using a developmental series of human fetal brains at 7-19 postconceptional weeks with emphasis on the forebrain to investigate whether the two genes are expressed in the same regions and zones in the same time window. We demonstrate by in situ hybridization and immunohistochemistry that the two homeobox genes are expressed during early fetal brain development in humans. PAX6 mRNA and protein were located in the proliferative zones of the neocortex and in single cells in the cortical preplate at 7 fetal weeks and in the developing cortical plate from 8 or 9 to 19 fetal weeks. The expression of PAX6 expanded into the ganglionic eminence just prior to the stage at which a stereological estimation showed an exponential rise in total cell number in this area. The MEIS2 gene was also present in the proliferative zones of the human fetal neocortex and a higher expression of MEIS2 than PAX6 was observed in these areas at 9 fetal weeks. Further, MEIS2 was expressed at a very high level in the developing ganglionic eminence and at a more moderate level in the cortical plate.


Asunto(s)
Proteínas del Ojo/metabolismo , Proteínas de Homeodominio/metabolismo , Factores de Transcripción Paired Box/metabolismo , Prosencéfalo/embriología , Prosencéfalo/metabolismo , Proteínas Represoras/metabolismo , Factores de Transcripción/metabolismo , Animales , Proteínas del Ojo/genética , Femenino , Edad Gestacional , Proteínas de Homeodominio/genética , Humanos , Hibridación in Situ , Factor de Transcripción PAX6 , Factores de Transcripción Paired Box/genética , Embarazo , Prosencéfalo/citología , Proteínas Represoras/genética , Factores de Transcripción/genética
10.
Eur J Endocrinol ; 162(3): 625-31, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19969558

RESUMEN

OBJECTIVE: Testicular germ cell cancer is the most common malignancy among young males. The pre-invasive precursor, carcinoma in situ testis (CIS), presumably originates from arrested and transformed fetal gonocytes. Given that GATA transcription factors have essential roles in embryonic and testicular development, we explored the expression of GATA-4, GATA-6, cofactor friend of GATA (FOG)-2, and downstream target genes during human testis development and addressed the question whether changes in this pathway may contribute to germ cell neoplasms. METHODS: Fetal testis, testicular CIS, and overt tumor samples were analyzed by immunohistochemistry for GATA-4, GATA-6, FOG-2, steroidogenic factor 1 (NR5A1/SF1), anti-Müllerian hormone/Müllerian-inhibiting substance (AMH), and inhibin-alpha (INHalpha). RESULTS: GATA-4 was not expressed in normal germ cells, except for a subset of gonocytes at the 15th gestational week. The CIS cells expressed GATA-4 and GATA-6 heterogeneously, whereas most of the CIS cells expressed GATA-4 cofactor FOG-2. GATA target gene SF-1 was expressed heterogeneously in CIS cells, whereas INHalpha and AMH were mostly negative. Seminomas and yolk sac tumors were positive for GATA-4 and GATA-6, but mostly negative for FOG-2 and the GATA target genes. In contrast, pluripotent embryonal carcinomas and choriocarcinomas were GATA-4 and GATA-6 negative. CONCLUSIONS: Differential expression of the GATA-4 target genes suggested cell-specific functions of GATA-4 in the germ and somatic cells. The GATA-4 expression in early fetal gonocytes, CIS, and seminoma cells but the absence in more mature germ cells is consistent with the early fetal origin of CIS cells and suggests that GATA-4 is involved in early germ cell differentiation.


Asunto(s)
Carcinoma in Situ/metabolismo , Proteínas de Unión al ADN/metabolismo , Factor de Transcripción GATA4/metabolismo , Factor de Transcripción GATA6/metabolismo , Neoplasias de Células Germinales y Embrionarias/metabolismo , Neoplasias Testiculares/metabolismo , Factores de Transcripción/metabolismo , Hormona Antimülleriana/metabolismo , Regulación del Desarrollo de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunohistoquímica , Inhibinas/metabolismo , Masculino , Factores de Empalme de ARN , Testículo/metabolismo
11.
Ann Anat ; 190(5): 421-7, 2008 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-18722098

RESUMEN

Mental retardation is seen in all individuals with Down syndrome (DS) and different brain abnormalities are reported. The aim of this study was to investigate if mental retardation at least in part is a result of a lower cell number in the neocortical part of the human fetal forebrain. We therefore compared brains of DS fetuses aged 19 weeks of gestation with normal control brains. The cell numbers were estimated using the optical fractionator method. The total cell number in the neocortical part of four DS human fetal forebrain was found to be substantially smaller in DS compared to the normal fetus. The average total cell number of 6.85 billion was equal to a reduction by 34% compared to the 10.4 billion cells in a normal fetal brain of that age. This study indicates that the mental retardation found in DS is based on a structural deficit in the human fetal brain already present in the second trimester.


Asunto(s)
Síndrome de Down/embriología , Síndrome de Down/patología , Feto/patología , Neocórtex/embriología , Neocórtex/patología , Autopsia , Recuento de Células/estadística & datos numéricos , Femenino , Edad Gestacional , Humanos , Discapacidad Intelectual/embriología , Discapacidad Intelectual/patología , Masculino , Embarazo , Segundo Trimestre del Embarazo , Corteza Visual/embriología , Corteza Visual/patología
12.
Pediatr Dev Pathol ; 11(1): 59-62, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18237239

RESUMEN

Two early-2nd-trimester fetuses were aborted as a result of nuchal edema and suspected severe heart malformation. At autopsy one fetus demonstrated nuchal edema, mild hydronephrosis, and cor triatriatum dexter associated with ventricular septal defect and tubular hypoplasia of the aortic arch. The other fetus demonstrated severe nuchal edema, and cor triatriatum dexter was the only malformation. Cor triatriatum dexter is a rare cardiac malformation characterized by division of the right atrium into 2 compartments by a usually fenestrated membrane representing remnants of the right valve of the embryonic sinus venosus. This malformation has been diagnosed in adults and children by echocardiography, surgery, or autopsy but has not previously been published in fetuses.


Asunto(s)
Corazón Triatrial/diagnóstico , Edema/patología , Enfermedades Fetales/diagnóstico , Feto/patología , Aborto Legal , Aorta Torácica/patología , Autopsia , Corazón Triatrial/complicaciones , Edema/complicaciones , Femenino , Defectos del Tabique Interventricular/patología , Humanos , Masculino , Cuello/patología , Embarazo , Segundo Trimestre del Embarazo
13.
Hum Reprod ; 23(4): 775-82, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18281244

RESUMEN

BACKGROUND: UTF-1 and REX-1/ZFP42 are transcription factors involved in pluripotency. Because of phenotypic similarities between pluripotent embryonic stem cells and testicular germ cell tumours (TGCT) and the derivation of pluripotent cells from testes, we investigated the expression of UTF-1 and REX-1 during human gonadal development and in TGCT. METHODS: Expression of UTF-1 and REX-1 was studied in 52 specimens from human gonadal development and in 86 samples from TGCT. RESULTS: UTF-1 and REX-1 were expressed throughout male gonadal development. In the mature testis, UTF-1 was expressed in spermatogonia, whereas REX-1 was expressed in meiotic cells and, together with OCT-3/4, in primary oocytes. Both UTF-1 and REX-1 were expressed in testicular carcinoma in situ and in TGCT. Contrarily to REX-1, UTF-1 was expressed in all spermatocytic seminomas. CONCLUSIONS: Unlike other pluripotency markers NANOG and OCT-3/4, UTF-1 and REX-1 are expressed throughout human testes development. The expression pattern indicated that UTF-1 plays a possible role in spermatogonial self-renewal, whereas expression of REX-1 in meiotic cells from both testes and ovary indicate a role in meiosis. UFT-1 and REX-1 are expressed in TGCT and the high abundance of UTF-1 in spermatocytic seminomas is consistent with the hypothesis that this tumour type originates from spermatogonia.


Asunto(s)
Factores de Transcripción de Tipo Kruppel/biosíntesis , Neoplasias de Células Germinales y Embrionarias/metabolismo , Proteínas Nucleares/biosíntesis , Ovario/metabolismo , Testículo/metabolismo , Transactivadores/biosíntesis , Niño , Femenino , Expresión Génica , Regulación Neoplásica de la Expresión Génica , Edad Gestacional , Humanos , Inmunohistoquímica , Hibridación in Situ , Lactante , Masculino , Fenotipo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
14.
Am J Obstet Gynecol ; 197(1): 56.e1-7, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17618757

RESUMEN

OBJECTIVE: The objective of the study was to test the hypothesis that the total number of cells in the cortical part of the cerebral wall is the same in intrauterine growth-restricted (IUGR) fetuses, compared with normally grown fetuses. STUDY DESIGN: The total cell number in the cerebral wall was estimated in 9 severely affected IUGR fetuses and 15 controls using the optical fractionator. Cell numbers were estimated within 4 developmental zones. The gestational ages were 19-41 weeks. RESULTS: The total cell number in the future cortex was significantly reduced in the IUGR fetuses, compared with controls. The daily increase in brain cells in the future cortex was only half of that of the controls. In the 3 other developmental zones, no significant differences in cell numbers could be demonstrated. CONCLUSIONS: IUGR in humans is associated with a severe reduction in cortical growth and a significant decrease in cell number in the future cortex.


Asunto(s)
Encefalopatías/embriología , Corteza Cerebral/citología , Corteza Cerebral/embriología , Retardo del Crecimiento Fetal/fisiopatología , Peso al Nacer , Estudios de Casos y Controles , Recuento de Células , Femenino , Edad Gestacional , Humanos , Recién Nacido , Masculino , Embarazo
15.
Cereb Cortex ; 17(11): 2573-8, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17218480

RESUMEN

The aim of this study was to quantify the total number of neurons and glial cells in the mediodorsal nucleus of the thalamus (MD) of 8 newborn human brains, in comparison to 8 adult human brains. The estimates of the cell numbers were obtained using the stereological principles of the optical fractionator. In the case of the adults, the total number of neurons in the entire MD was an average of 41% lower than in the newborn, which was statistically highly significant (P < 0.001). The estimated average total number of neurons in MD thalamus of the newborns was 11.2 million (coefficient of variation [CV] = standard deviation/mean = 0.16), compared with the adults' 6.43 million (CV = 0.15). The glial cell numbers were substantially higher in the adult brains, with an increase of almost 4 times from 10.6 million at birth to 36.3 million in the fully developed adult brain. This is the first demonstration of a higher number of human neurons in the brain of newborns compared with the adult.


Asunto(s)
Envejecimiento/patología , Núcleo Talámico Mediodorsal/citología , Neuronas/citología , Adulto , Anciano , Anciano de 80 o más Años , Recuento de Células , Femenino , Humanos , Recién Nacido , Masculino , Persona de Mediana Edad
16.
APMIS ; 114(4): 239-46, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16689822

RESUMEN

Neural tube defects (NTDs) are congenital malformations of the central nervous system (CNS) secondary to abnormal closure of the neural tube during embryonic development. This study provides information on NTD rate, distribution, associated morphologic anomalies and organ weights in a Danish fetal and perinatal autopsy series during a 16 year period. The data were extracted from the autopsy reports of a consecutive series of 1984 fetal and perinatal autopsies from the Copenhagen area performed in the period 1989-2004. Registered parameters included: The location and morphology of the NTD, associated morphological anomalies, and organ weights. Organ weights were evaluated according to new fetal autopsy standards and grouped as low, normal or high. Ninety-seven NTD cases were found (4.9%): Spina bifida (38 cases), cephalocele (17 cases) and anencephaly (42 cases). 63% of NTD cases had associated morphologic anomalies. Among the most common were hydrocephalus, NTD in another region, and anomalies in the urogenital system. 58% of the NTD cases had abnormal weight of one or more organs. Most notable was low adrenal weight not only in anencephalic fetuses but also in cases with cephalocele, suggesting a possible association.


Asunto(s)
Anencefalia/patología , Encefalocele/patología , Feto/anomalías , Feto/patología , Disrafia Espinal/patología , Femenino , Humanos , Tamaño de los Órganos , Embarazo
18.
Pediatr Dev Pathol ; 8(2): 204-17, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15747100

RESUMEN

Standards for body parameters and organ weights are important tools in fetal and perinatal pathology. Previously there has been only a weak emphasis on the effect of maceration on dimensions and weights. This study provides autopsy standards for body weight, body dimensions, and fresh organ weights for nonmacerated fetuses and for mildly, moderately, and markedly macerated fetuses at 12 to 43 weeks of gestation. Cases were selected from a consecutive series of 1800 fetal and perinatal autopsies. Cases with malformations, hydrops, infection, or chromosomal abnormality, fetuses from multiple births, and infants who lived longer than 24 h were excluded. In each case the maceration was graded and body weight and 4 body dimensions were recorded before organ examination. Organs were weighed immediately and before fixation. Growth curves were fitted according to appropriate mathematical methods and the effects of maceration on each value were tested statistically. We found that weights of the liver, thymus, and spleen markedly decrease with increasing maceration. The weights of the lungs, kidneys, and adrenals decreased modestly, whereas weights of the heart and brain changed only slightly. Body length increased slightly with maceration, whereas body weight and head circumference were unaffected. User-friendly charts and tables of mean values and standard deviations for nonmacerated and macerated fetuses are provided.


Asunto(s)
Antropometría/métodos , Autopsia/métodos , Pesos y Medidas Corporales/normas , Muerte Fetal/patología , Feto/anatomía & histología , Cambios Post Mortem , Biometría , Desarrollo Fetal , Humanos , Tamaño de los Órganos
19.
Clin Cancer Res ; 10(24): 8521-30, 2004 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-15623634

RESUMEN

PURPOSE: Transcription factor activator protein-2gamma (TFAP2C, AP-2gamma) was reported previously in extraembryonic ectoderm and breast carcinomas but not in the testis. In our recent gene expression study we detected AP-2gamma in carcinoma in situ testis (CIS, or intratubular germ cell neoplasia), precursor of testicular germ cell tumors. In this study we aimed to investigate the expression pattern of AP-2gamma and to shed light on this factor in germ cell differentiation and the pathogenesis of germ cell neoplasia. EXPERIMENTAL DESIGN: We analyzed expression pattern of AP-2gamma at the RNA and protein level in normal human tissues and a panel of tumors and tumor-derived cell lines. In the gonads, we established the ontogeny of expression of AP-2gamma in normal and dysgenetic samples. We also investigated the regulation of AP-2gamma by steroids and retinoic acid. RESULTS: We detected abundant AP-2gamma in testicular CIS and in testicular germ cell tumors of young adults and confirmed differential expression of AP-2gamma in somatic tumors. We found that AP-2gamma expression was regulated by retinoic acid in an embryonal carcinoma cell line (NT2). The investigation of ontogeny of AP-2gamma protein expression in fetal gonads revealed that it was confined to oogonia/gonocytes and was down-regulated with germ cell differentiation. In some prepubertal intersex cases, AP-2gamma was detected outside of the normal window of expression, probably marking neoplastic transformation of germ cells. CONCLUSIONS: AP-2gamma is developmentally regulated and associated with the undifferentiated phenotype in germ cells. This transcription factor may be involved in self-renewal and survival of immature germ cells and tissue-specific stem cells. AP-2gamma is a novel marker of testicular CIS and CIS-derived tumors.


Asunto(s)
Biomarcadores de Tumor , Carcinoma in Situ/metabolismo , Proteínas de Unión al ADN/metabolismo , Regulación del Desarrollo de la Expresión Génica , Neoplasias Ováricas/metabolismo , Neoplasias Testiculares/metabolismo , Factores de Transcripción/metabolismo , Adolescente , Adulto , Carcinoma in Situ/genética , Diferenciación Celular , Niño , Preescolar , Proteínas de Unión al ADN/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Germinoma/etiología , Germinoma/metabolismo , Disgenesia Gonadal/complicaciones , Disgenesia Gonadal/patología , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Neoplasias Ováricas/genética , Embarazo , Esteroides/farmacología , Neoplasias Testiculares/genética , Factor de Transcripción AP-2 , Factores de Transcripción/genética , Tretinoina/farmacología
20.
Hum Reprod ; 19(6): 1338-44, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15105401

RESUMEN

BACKGROUND: To investigate how long fetal germ cells retain pluripotency, which may be linked to their ability to transform into histologically variable tumours, we examined the expression of OCT-3/4 (POU5F1), a transcription factor essential for the maintenance of totipotency in embryonic stem cells. METHODS: The ontogeny of expression of OCT-3/4 was studied in 74 specimens of normal human gonads during development and in 58 samples of gonads from cases with testicular dysgenesis syndrome (TDS), including disorders of sex differentiation and malignant changes. RESULTS: OCT-3/4 expression was found in primordial germ cells during migration to the gonadal ridges and in the indifferent gonad. The expression in testes gradually decreased until approximately 20 weeks of gestation, and thereafter it was more rapidly down-regulated, but persisted in a few cells until 3-4 months of postnatal age, which coincides with the final differentiation of gonocytes into infantile spermatogonia. Subsequently, OCT-3/4 was not detected in normal testes. In the ovaries, OCT-3/4 was expressed in primordial oogonia, but was down-regulated in oocytes that formed primary follicles. The pattern of expression was heterogeneous in dysgenetic and intersex cases, with OCT-3/4-positive gonocytes detected in this series until 14 months of age. Visibly neoplastic gonadoblastoma and carcinoma in situ (CIS) expressed abundant OCT-3/4 regardless of the age. CONCLUSIONS: In the human ovary, OCT-3/4 is silenced at the onset of the first meiotic prophase, whereas in the testis, down-regulation of OCT-3/4 is a gradual process associated with differentiation of gonocytes. This normal pattern of expression is disturbed in dysgenetic gonads, especially in rare intersex cases, thus increasing the risk of malignant transformation. The high abundance of OCT-3/4 in CIS cells is consistent with their early fetal origin and pluripotency.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Disgenesia Gonadal/embriología , Ovario/embriología , Testículo/embriología , Factores de Transcripción/metabolismo , Cadáver , Estudios de Casos y Controles , Proteínas de Unión al ADN/genética , Embrión de Mamíferos/metabolismo , Desarrollo Embrionario , Femenino , Silenciador del Gen , Germinoma/embriología , Humanos , Masculino , Factor 3 de Transcripción de Unión a Octámeros , Factores de Transcripción/genética
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA