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1.
Am J Med Genet A ; 164A(5): 1227-33, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24458767

RESUMO

Monochorionic-diamniotic twins are usually monozygotic twins and known to be associated with adverse obstetric and perinatal outcomes. Cases of discordant karyotype of monozygotic twins are rare and most involves sex chromosomes. We present the first case of monochorionic twins with discordant karyotype manifested as mosaic trisomy 14 in one twin (B) and a normal karyotype in the other (A). We describe the postmortem pathological and imaging findings of the trisomic twin and for the first time neuropathological findings of this entity. Metaphase chromosome analysis of twin B using fetal tissue showed a 47,XX, +14 karyotype. Chromosomal microarray analysis (CMA) using fetal tissue revealed 38% mosaicism. CMA with placental tissue from both sides demonstrated normal karyotype and confirmed monozygosity, highlighting the value of array based testing on diagnosing mosaicism and zygosity.


Assuntos
Trissomia/diagnóstico , Trissomia/genética , Gêmeos Monozigóticos , Alelos , Autopsia , Cromossomos Humanos Par 14/genética , Hibridização Genômica Comparativa , Evolução Fatal , Feminino , Genótipo , Humanos , Cariotipagem , Imageamento por Ressonância Magnética , Mosaicismo , Polimorfismo de Nucleotídeo Único , Ultrassonografia Pré-Natal
2.
Am J Pathol ; 173(1): 42-56, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18535181

RESUMO

Premature infants are at risk for bronchopulmonary dysplasia, a complex condition characterized by impaired alveolar development and increased alveolar epithelial apoptosis. The functional involvement of pulmonary apoptosis in bronchopulmonary dysplasia- associated alveolar disruption remains undetermined. The aims of this study were to generate conditional lung-specific Fas-ligand (FasL) transgenic mice and to determine the effects of FasL-induced respiratory epithelial apoptosis on alveolar remodeling in postcanalicular lungs. Transgenic (TetOp)(7)-FasL responder mice, generated by pronuclear microinjection, were bred with Clara cell secretory protein (CCSP)-rtTA activator mice. Doxycycline (Dox) was administered from embryonal day 14 to postnatal day 7, and lungs were studied between embryonal day 19 and postnatal day 21. Dox administration induced marked respiratory epithelium-specific FasL mRNA and protein up-regulation in double-transgenic CCSP-rtTA(+)/(TetOp)(7)-FasL(+) mice compared with single-transgenic CCSP-rtTA(+) littermates. The Dox-induced FasL up-regulation was associated with dramatically increased apoptosis of alveolar type II cells and Clara cells, disrupted alveolar development, decreased vascular density, and increased postnatal lethality. These data demonstrate that FasL-induced alveolar epithelial apoptosis during postcanalicular lung remodeling is sufficient to disrupt alveolar development after birth. The availability of inducible lung-specific FasL transgenic mice will facilitate studies of the role of apoptosis in normal and disrupted alveologenesis and may lead to novel therapeutic approaches for perinatal and adult pulmonary diseases characterized by dysregulated apoptosis.


Assuntos
Apoptose/fisiologia , Células Epiteliais/patologia , Proteína Ligante Fas/metabolismo , Pneumopatias/patologia , Alvéolos Pulmonares/crescimento & desenvolvimento , Animais , Sequência de Bases , Western Blotting , Modelos Animais de Doenças , Proteína Ligante Fas/genética , Feminino , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Pneumopatias/fisiopatologia , Masculino , Camundongos , Camundongos Transgênicos , Microscopia Eletrônica de Transmissão , Dados de Sequência Molecular , Mucosa Respiratória/metabolismo , Mucosa Respiratória/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transgenes
4.
Pediatr Dev Pathol ; 12(1): 35-41, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-18462010

RESUMO

Whereas the effects of chemotherapy during pregnancy for mother and fetus are well described, its effects on the placenta remain largely undetermined. We performed a retrospective clinicopathologic analysis of the placenta following chemotherapy. Charts were reviewed for type of malignancy, type and timing of chemotherapy, and fetal and pregnancy outcome. Placentas were studied by standard pathologic analysis as well as computer-assisted morphometry and fluorescence in situ hybridization (FISH) analysis. Patients (n = 13) underwent chemotherapy during pregnancy for carcinoma of breast (3), ovary (2), cervix (2), salivary gland (1), lymphoma/leukemia (4), or rhabdomyosarcoma (1). Eleven patients were treated with DNA-active cytotoxic agents during the 2nd and/or 3rd trimesters; their placentas showed nonspecific findings, including villous hypermaturity, distal villous hypoplasia, villous edema, and excessive extravillous trophoblast, and 4/11 (36%) were small-for-age. In one case (rhabdomyosarcoma), the mother was exposed to cytotoxic agents throughout the entire pregnancy. In this case, associated with severe congenital anomalies, the placenta showed striking nuclear pleomorphism of the extravillous trophoblast of the chorion laeve, associated with FISH-demonstrated hyperpolyploidy. One patient was treated with the targeted tyrosine kinase inhibitor, imatinib, in 2 consecutive pregnancies; these placentas showed no specific anomalies. Our findings suggest that chemotherapy during the 1st trimester induces excessive polyploidization of the chorion laeve trophoblast, likely representing an adaptive response to intraamniotic toxins. Second and 3rd trimester exposure to cytotoxic agents may predispose to placental underdevelopment. However, without appropriate controls (untreated patients with equivalent malignancies), the specific effects of chemotherapy in this group are difficult to assess.


Assuntos
Antineoplásicos/efeitos adversos , Placenta/efeitos dos fármacos , Placenta/patologia , Complicações Neoplásicas na Gravidez/tratamento farmacológico , Anormalidades Múltiplas/induzido quimicamente , Adolescente , Adulto , Feminino , Humanos , Hibridização in Situ Fluorescente , Recém-Nascido , Gravidez , Primeiro Trimestre da Gravidez , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez , Estudos Retrospectivos
5.
Am J Physiol Endocrinol Metab ; 291(2): E221-33, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16478781

RESUMO

These studies aim to investigate subcellular distribution of angiotensin II (ANG II) in rat luteal cells, identify other bioactive angiotensin peptides, and investigate a role for angiotensin peptides in luteal steroidogenesis. Confocal microscopy showed ANG II distributed within the cytoplasm and nuclei of luteal cells. HPLC analysis showed peaks that eluted with the same retention times as ANG-(1-7), ANG II, and ANG III. Their relative concentrations were ANG II >or= ANG-(1-7) > ANG III, and accumulation was modulated by quinapril, an inhibitor of angiotensin-converting enzyme (ACE), Z-proprolinal (ZPP), an inhibitor of prolyl endopeptidase (PEP), and parachloromercurylsulfonic acid (PCMS), an inhibitor of sulfhydryl protease. Phenylmethylsulfonyl fluoride (PMSF), a serine protease inhibitor, did not affect peptide accumulation. Quinapril, ZPP, PCMS, and PMSF, as well as losartan and PD-123319, the angiotensin receptor type 1 (AT1) and type 2 (AT2) receptor antagonists, were used in progesterone production studies. ZPP significantly reduced luteinizing hormone (LH)-dependent progesterone production (P < 0.05). Quinapril plus ZPP had a greater inhibitory effect on LH-stimulated progesterone than either inhibitor alone, but this was not reversed by exogenous ANG II or ANG-(1-7). Both PCMS and PMSF acutely blocked LH-stimulated progesterone, and PCMS blocked LH-sensitive cAMP accumulation. Losartan inhibited progesterone production in permeabilized but not intact luteal cells and was reversed by ANG II. PD-123319 had no significant effect on luteal progesterone production in either intact or permeabilized cells. These data suggest that steroidogenesis may be modulated by angiotensin peptides that act in part through intracellular AT1 receptors.


Assuntos
Angiotensina II/metabolismo , Angiotensina I/metabolismo , Células Lúteas/metabolismo , Fragmentos de Peptídeos/metabolismo , Esteroides/metabolismo , Frações Subcelulares/metabolismo , Animais , Células Cultivadas , Feminino , Ratos , Transdução de Sinais/fisiologia , Distribuição Tecidual
6.
Am J Physiol Cell Physiol ; 285(3): C642-51, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12724141

RESUMO

In luteal cells, prostaglandin (PG)F2a mobilizes intracellular calcium concentration ([Ca]i), generates reactive oxygen species (ROS), depletes ascorbic acid (AA) levels, inhibits steroidogenesis, and ultimately induces cell death. We investigated the hypothesis that [Ca]i mobilization stimulates ROS, which results in depletion of cellular AA in rat luteal cells. We used a self-referencing AA-selective electrode that noninvasively measures AA flux at the extended boundary layer of single cells and fluorescence microscopy with fura 2 and dichlorofluorescein diacetate (DCF-DA) to measure [Ca]i and ROS, respectively. Menadione, a generator of intracellular superoxide radical (O2-), PGF2a, and calcium ionophore were shown to increase [Ca]i and stimulate intracellular ROS. With calcium ionophore and PGF2a, but not menadione, the generation of ROS was dependent on extracellular calcium influx. In unstimulated cells there was a net efflux of AA of 121.5 +/- 20.3 fmol x cm-1 x s-1 (mean +/- SE, n = 8), but in the absence of extracellular calcium the efflux was significantly reduced (10.3 +/- 4.9 fmol x cm-1 x s-1; n = 5, P < 0.05). PGF2a and menadione stimulated AA efflux, but calcium ionophore had no significant effect. These data suggest two AA regulatory mechanisms: Under basal conditions, AA efflux is calcium dependent and may represent recycling and maintenance of an antioxidant AA gradient at the plasma membrane. Under luteolytic hormone and/or oxidative stress, AA efflux is stimulated that is independent of extracellular calcium influx or generation of ROS. Although site-specific mobilization of calcium pools and ROS cannot be ruled out, the release of AA by PGF2a-stimulated luteal cells may occur through other signaling pathways.


Assuntos
Ácido Ascórbico/farmacocinética , Cálcio/metabolismo , Corpo Lúteo/metabolismo , Luteólise/fisiologia , Animais , Antifibrinolíticos/farmacologia , Apoptose/fisiologia , Corpo Lúteo/citologia , Corpo Lúteo/efeitos dos fármacos , Dinoprosta/metabolismo , Feminino , Ionomicina/farmacologia , Ionóforos/farmacologia , Microeletrodos , Ratos , Ratos Endogâmicos , Espécies Reativas de Oxigênio/metabolismo , Esteroides/biossíntese , Vitamina K 3/farmacologia
7.
Cancer Invest ; 22(5): 670-7, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15581047

RESUMO

PURPOSE: To conduct a phase I study incorporating trastuzumab with paclitaxel, cisplatin, and radiation for adenocarcinoma of the esophagus. METHODS AND MATERIALS: Patients with adenocarcinoma of the esophagus without distant organ metastases were eligible. All patients received cisplatin 25 mg/m2 and paclitaxel 50 mg/m2 weekly for 6 weeks with radiation 50.4 Gy. HER-2/neu-positive patients (2+/3+ by immunohistochemistry) received weekly trastuzumab at dose levels of 1, 1.5, or 2 mg/kg weekly for 5 weeks after an initial bolus of 2, 3, or 4 mg/kg, respectively. HER-2/neu-negative patients received the same chemoradiation without trastuzumab as a control for toxicity. Dose-limiting toxicities were defined as grade 3 esophageal, cardiac, or pulmonary toxicity. RESULTS: Twelve of 36 screened patients (33%) overexpressed HER-2/neu by immunohistochemistry (seven 3+ and five 2+). Eight of 12 patients with HER-2/neu overexpression by IHC had an increase in the number of HER-2/neu genes, six from amplification of the HER-2/ neu gene and two were hypderdiploid for chromosome 17. Thirty patients were enrolled (12 HER-2/neu-positive and 18 HER-2/neu-negative controls). No increase in toxicity was seen with the addition of trastuzumab. One of 12 patients in the trastuzumab arm and 8 of 17 in the control arm had grade 3 esophagitis (p < or = .026). Mean left ventricular ejection fraction for the trastuzumab group was 57% before treatment and 56% after treatment. CONCLUSION: HER-2/neu is overexpressed in approximately one-third of esophageal adenocarcinomas. Trastuzumab can be added at full dose to cisplatin, paclitaxel, and radiation. Future studies of trastuzumab in esophageal adenocarcinoma are indicated.


Assuntos
Adenocarcinoma/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Esofágicas/terapia , Adenocarcinoma/genética , Idoso , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Humanizados , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Terapia Combinada , Neoplasias Esofágicas/genética , Amplificação de Genes , Genes erbB-2/genética , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Paclitaxel/administração & dosagem , Paclitaxel/efeitos adversos , Radioterapia , Trastuzumab
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