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1.
Br J Cancer ; 88(6): 951-6, 2003 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-12644836

RESUMO

Transport system x(c)(-) is a member of plasma membrane heterodimeric amino-acid transporters and consists of two protein components, xCT and 4F2hc. This system mediates cystine entry coupled with the exodus of intracellular glutamate and regulates the intracellular glutathione (GSH) levels in most mammalian cultured cells. We studied the activity of system x(c)(-) and GSH content in human ovarian cancer cell line (A2780) and its cisplatin (CDDP)-resistant variant (A2780DDP). The rate of cystine uptake was approximately 4.5-fold higher in A2780DDP cells than in A2780 cells and the cystine uptake in A2780DDP cells was mediated by system x(c)(-). Intracellular GSH content was much higher in A2780DDP cells but it fell drastically in the presence of excess glutamate, which inhibited the cystine uptake competitively. xCT and 4F2hc mRNAs were definitely expressed in A2780DDP cells, but far less in A2780 cells. Expression of system x(c)(-) activity by transfection with cDNAs for xCT and 4F2hc made A2780 cells more resistant to CDDP. Similar results on the cystine uptake were obtained in human colonic cancer cell lines. These findings suggest that the system x(c)(-) plays an important role in maintaining the higher levels of GSH and consequently in CDDP resistance in cancer cell lines.


Assuntos
Sistemas de Transporte de Aminoácidos , Antineoplásicos/farmacologia , Cisplatino/farmacologia , Neoplasias do Colo/patologia , Cistina/farmacocinética , Glutationa/farmacologia , Neoplasias Ovarianas/patologia , DNA Complementar , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Transfecção , Células Tumorais Cultivadas
2.
Magn Reson Imaging ; 19(5): 635-42, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11672621

RESUMO

Antenatal diagnosis of placenta accreta with MR is not easy even now because T2-weighted images (T2WI) cannot differentiate chorionic villi from decidua basalis. We performed dynamic contrast MRI to study whether trophoblastic villi could be separately demonstrated from the decidua basalis, and whether the contrast resolution between the placenta and myometrium could improve compared to T2WI. Six pregnant women with prior cesarean section were examined at 34-38 gestational weeks. Sagittal T2-weighted images with fast spin echo sequences and dynamic contrast studies with fast field echo sequence every 10-14 s after contrast injection were performed. We analyzed the enhancing pattern of the placenta and compared the contrast between placenta and myometrium. We reviewed medical records to identify complications during the placental delivery and the complications of their newborns. In the early phase after contrast enhancement, multiple foci of the strong lobular enhancement were observed in all cases. Other parts of placenta were slowly but strongly enhanced following them. We speculated that the former corresponded to intervillous space and the latter decidua basalis. The contrast between placenta and myometrium tended to be distinct near the inner cervical os on both T2WI and dynamic contrast study. On the other hand, it was indistinct in the upper part of the uterine body on T2WI despite it was clearly demonstrated on dynamic contrast study. The placentae were delivered without any complication in all cases. Although two neonates showed fetal distress, none of the infant remained any sequelae at the time of the discharge. The other four were well although one of them complicated with meconium staining. As dynamic contrast MRI can differentiate chorionic villi and decidua basalis, and can provide excellent contrast between placenta and myometrium at anywhere within the uterus, it may be a promising technique for antepartum diagnosis of the placenta accreta.


Assuntos
Aumento da Imagem , Imageamento por Ressonância Magnética , Placenta Acreta/diagnóstico , Diagnóstico Pré-Natal , Vilosidades Coriônicas/patologia , Decídua/patologia , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Miométrio/patologia , Placenta/patologia , Gravidez , Trofoblastos/patologia
3.
Clin Chem ; 47(9): 1622-6, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11514395

RESUMO

BACKGROUND: The purpose of this study was to determine whether aneuploid fetal nucleated erythrocytes (NRBCs) could be detected in maternal blood through the use of fluorescent PCR amplification with polymorphic short tandem repeat (STR) markers as an alternative or complementary method to analysis by fluorescent in situ hybridization (FISH). METHODS: Peripheral blood samples were obtained from women who had just undergone termination of pregnancy because of fetal trisomy 21 (three cases, 47,XY,+21; four cases, 47,XX,+21). Candidate fetal cells were isolated by flow-sorting by antibodies to the gamma chain of fetal hemoglobin and Hoechst 33342. FISH analysis was performed by the use of chromosome-specific probes for X, Y, and 21. Fetal NRBCs, as defined by the presence of gamma staining, characteristic morphology, and three chromosome 21 signals, along with maternal leukocytes, defined as gamma negative and two chromosome 21 signals, were micromanipulated separately and subjected to fluorescent PCR amplification of chromosome 21 STR markers (D21S11, D21S1411, and/or D21S1412). RESULTS: In five of seven cases analyzed, fetal NRBCs were aneuploid, as determined by the presence of triallelic or diallelic peaks of chromosome 21 sequences when compared with sequences from the maternal leukocytes. CONCLUSIONS: Fluorescent PCR amplification of STRs can detect fetal aneuploidy and may be useful in the setting of poor hybridization efficiency with FISH analysis. These results suggest that combined fetal aneuploidy and single-gene diagnoses by the use of DNA microarrays may be feasible in the near future.


Assuntos
Síndrome de Down/diagnóstico , Eritroblastos/química , Sangue Fetal/citologia , Repetições de Microssatélites , Aneuploidia , Feminino , Humanos , Reação em Cadeia da Polimerase , Espectrometria de Fluorescência
4.
Arch Gynecol Obstet ; 265(1): 53-4, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11327096

RESUMO

We treated a case of primary fetal hydrothorax with hydrops. A pleuroamniotic shunt catheter inserted at 30 weeks accomplished resolution of hydrops and was maintained until cesarean delivery at 34 weeks with no need for further prenatal intervention. At age 9 months, the infant showed no effusion or pulmonary compromise.


Assuntos
Doenças Fetais/cirurgia , Hidropisia Fetal/complicações , Hidrotórax/cirurgia , Adulto , Âmnio/cirurgia , Líquido Amniótico , Anastomose Cirúrgica , Cateterismo , Drenagem , Feminino , Doenças Fetais/diagnóstico por imagem , Idade Gestacional , Humanos , Hidrotórax/complicações , Hidrotórax/diagnóstico por imagem , Pleura/cirurgia , Gravidez , Ultrassonografia Pré-Natal
5.
Hum Genet ; 107(1): 28-32, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10982031

RESUMO

The nucleated erythrocyte (NRBC) is one of the target fetal cell types for noninvasive genetic diagnosis using maternal peripheral blood. However, it is now known that pregnancy can stimulate the production of maternal NRBCs. When isolating female gamma-positive NRBCs, fluorescence in situ hybridization (FISH) analysis may show two X chromosome signals per nucleus, and therefore it cannot be conclusively determined whether the isolated cells are fetal or maternal in origin. The purpose of this study was to develop a means of verifying that a female cell is fetal on the basis of polymorphic short tandem repeat markers. Peripheral blood samples were obtained from women who had just undergone termination of pregnancy. Nucleated candidate fetal cells were isolated by flow-sorting using antibody to the gamma-chain of fetal hemoglobin and Hoechst 33342. FISH analysis was performed using X and Y chromosome specific probes. Female gamma-positive cells and leukocytes were micromanipulated separately and subjected to fluorescent polymerase chain reaction amplification of chromosome 21 and/or 18 STR markers (D21S11, D21S1411, D21S1412, and D18S535). In all ten cases analyzed, the gamma-positive female candidate fetal cells were determined to be fetal in origin by the presence of shared and nonshared DNA polymorphisms when compared with maternal leukocytes. These results show that genetic analysis can be performed on all fetal NRBCs, including female fetal cells that cannot be distinguished from maternal cells based on FISH analysis alone.


Assuntos
DNA/análise , DNA/sangue , Eritroblastos/química , Feto/citologia , Polimorfismo Genético , Sequências de Repetição em Tandem , Separação Celular , Cromossomos Humanos Par 21 , Feminino , Corantes Fluorescentes/metabolismo , Marcadores Genéticos , Idade Gestacional , Humanos , Hibridização in Situ Fluorescente , Reação em Cadeia da Polimerase , Gravidez
6.
J Hum Genet ; 45(3): 138-41, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10807538

RESUMO

Preeclampsia is associated with thrombosis of the intervillous or spiral artery. A deletion/insertion polymorphism (4G or 5G) in the promoter of the plasminogen activator inhibitor type 1 (PAI-1) gene is suggested to be involved in regulating the synthesis of the inhibitor, 4G allele, being associated with the enhanced gene expression and plasma PAI-1 levels. We assessed the association between preeclampsia and the 4G/5G polymorphism of the PAI-1 gene in 115 preeclamptic patients, 210 pregnant controls, and 298 healthy volunteer controls. The frequency of the homozygotes for the 4G allele was significantly higher in the patients than in the control pregnant women (P = 0.04) or in the healthy volunteers (P = 0.02). The 4G allele frequency was also significantly higher in the patients than in the control group of pregnant women (P = 0.03) and in the healthy volunteers (P = 0.02). These results suggest that the presence of the 4G/4G genotype of the PAI-1 gene is one of the risk factors for preeclampsia.


Assuntos
Inibidor 1 de Ativador de Plasminogênio/genética , Pré-Eclâmpsia/genética , Alelos , Estudos de Casos e Controles , Feminino , Frequência do Gene , Genótipo , Homozigoto , Humanos , Polimorfismo Genético , Pré-Eclâmpsia/epidemiologia , Gravidez , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença
8.
Prenat Diagn ; 19(10): 980-2, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10521827

RESUMO

Urinary retention is an adverse effect of antipsychotic drugs that has not been previously reported in the fetus. We have diagnosed megacystis in a fetus possibly caused by transplacental exposure to the antipsychotic drugs being administered to the mother. Two weeks after the mother stopped taking the drugs, the size of the enlarged fetal urinary bladder returned to normal. Sonographic examination of the neonate revealed an anatomically normal urinary tract, with a normal bladder capacity and urination.


Assuntos
Antipsicóticos/farmacocinética , Troca Materno-Fetal/fisiologia , Placenta/metabolismo , Gravidez/metabolismo , Bexiga Urinária/anormalidades , Adulto , Feminino , Humanos , Retenção Urinária/induzido quimicamente
9.
J Obstet Gynaecol Res ; 25(6): 407-10, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10680338

RESUMO

OBJECTIVE: Our purpose was to evaluate plasma levels of brain natriuretic peptide (pBNP) and cyclic guanosine monophosphate (pcGMP) in preeclamptic patients and controls. STUDY DESIGN: Blood samples were obtained from 35 patients with preeclampsia and from the same women during the subsequent puerperal period. The control group consisted of normotensive pregnant women, matched with the patients for age, gestational age, and parity. The concentrations of pBNP and pcGMP were determined by the RIA method. Statistical analysis was performed using the Mann-Whitney's U test. RESULTS: The pBNP level in the preeclampsia group was significantly increased, to 7-fold that of the control group. The pcGMP level was 50% higher in the preeclampsia group than in the control group, but this was not significant. Both the pBNP level and the pcGMP level in the puerperal period did not significantly differ between the patients and the controls. CONCLUSION: The pBNP concentrations increased in the preeclamptic women, and then these compensations were normalized in the puerperal period.


Assuntos
GMP Cíclico/sangue , Peptídeo Natriurético Encefálico/sangue , Pré-Eclâmpsia/sangue , Gravidez/sangue , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Pré-Eclâmpsia/fisiopatologia , Valores de Referência
10.
Prenat Diagn ; 17(8): 743-52, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9267898

RESUMO

The purpose of this study was to determine the proportion of fetal nucleated red blood cells (NRBCs) among enriched NRBCs and to evaluate the effectiveness of enriching NRBCs in maternal blood using fluorescence-activated cell sorting (FACS) to separate NRBCs. The origin of enriched NRBCs was determined using fluorescence in situ hybridization (FISH) methods. Y-specific signals were observed in 4.6 +/- 1.5 per cent of the enriched cells from 14 of 16 (87.5 per cent) pregnant women who gave birth to boys. In this series, the specificity of the fetal sex diagnosis was 100 per cent, the sensitivity 88 per cent, and the negative predictive value 86 per cent. Fetal NRBCs are present in maternal blood and FACS has the potential to enrich fetal NRBCs. Fetal cells were estimated to be enriched more than 10,000-fold in the first trimester and more than 100-fold in the third trimester. Average frequencies of fetal cells in maternal blood were 8.1 x 10(-5) and 1.6 x 10(-5) in the first trimester and the second/third trimesters. However, most of the NRBCs in maternal blood are maternal in origin.


Assuntos
Contagem de Eritrócitos , Eritrócitos/ultraestrutura , Sangue Fetal/citologia , Citometria de Fluxo , Antígenos CD/análise , Antígenos de Diferenciação de Linfócitos B/análise , Antígenos CD36/análise , Núcleo Celular , Feminino , Glicoforinas/análise , Humanos , Hibridização in Situ Fluorescente , Gravidez , Receptores da Transferrina
11.
Prenat Diagn ; 17(7): 670-4, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9249869

RESUMO

We present the first report on the use of helical computed tomography (CT), a new, non-invasive diagnostic technique that produces three-dimensional (3-D) images, in prenatal diagnosis. This technique was used to construct 3-D images in the prenatal diagnosis of two anomalous fetuses. The 3-D images provided clear information about the anomalies: trisomy 18 in one case and cystic hygroma in the other. In one case, rapid intervention after a planned Caesarean section prevented respiratory distress. Surgery to correct the anomaly was performed 2 days postnatally; the infant recovered uneventfully.


Assuntos
Anormalidades Congênitas/diagnóstico por imagem , Processamento de Imagem Assistida por Computador , Diagnóstico Pré-Natal , Tomografia Computadorizada por Raios X/métodos , Adulto , Feminino , Humanos , Gravidez
12.
Fetal Diagn Ther ; 12(4): 241-3, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9354885

RESUMO

We report 2 cases of fetal heart failure associated with large placental chorioangiomas. One fetus exhibited serious hydrops on the initial fetal echocardiogram and was ultimately stillborn. The fetus in the other case exhibited cardiomegaly. Following the premature termination of the pregnancy, the fetus received medical treatment and recovered in 7 days. Monitoring the fetal cardiac size with ultrasonography is recommended to determine the optimal time of delivery in cases of large placental angioma that are diagnosed prenatally.


Assuntos
Doenças Fetais/etiologia , Cardiopatias/etiologia , Hemangioma/complicações , Doenças Placentárias/complicações , Complicações Neoplásicas na Gravidez , Aborto Espontâneo/etiologia , Adulto , Feminino , Doenças Fetais/diagnóstico por imagem , Cardiopatias/diagnóstico por imagem , Hemangioma/diagnóstico por imagem , Humanos , Recém-Nascido , Doenças Placentárias/diagnóstico por imagem , Gravidez , Complicações Neoplásicas na Gravidez/diagnóstico por imagem , Neoplasias Trofoblásticas , Ultrassonografia Pré-Natal
13.
J Obstet Gynaecol Res ; 23(3): 255-9, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9255038

RESUMO

OBJECTIVE: To determine the effect of maternal exercise on the fetal blood flow of normal and growth-retarded fetuses. METHODS: The effect of maternal exercise on fetal blood flow was investigated with 24 pregnant women between 36 and 42 weeks' gestation. Seventeen pregnancies were uncomplicated (normal group) and the other 7 were complicated with growth-retarded fetuses (IUGR group). They underwent graded walking on a treadmill with an upper limit of 150 bpm for the maternal heart rate. The systolic over diastolic velocity ratio (S/D ratio) of the umbilical artery was measured before exercise, and at 3, 5, 10, and 15 minutes after exercise. RESULTS: The mean S/D ratio of the IUGR group before exercise was significantly higher than that of the normal group (p < 0.05). The S/D ratio did not change significantly after exercise, in either the normal group or the IUGR group. CONCLUSION: This study suggests that maternal exercise at this level of intensity and duration does not have any harmful effect, even on growth-retarded fetuses that might have placental dysfunctions.


Assuntos
Exercício Físico/fisiologia , Retardo do Crescimento Fetal/fisiopatologia , Feto/irrigação sanguínea , Artérias Umbilicais/fisiopatologia , Diástole , Feminino , Frequência Cardíaca , Frequência Cardíaca Fetal , Humanos , Gravidez , Sístole
14.
J Med Genet ; 34(6): 525-6, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9192280

RESUMO

A common missense mutation in the methylenetetrahydrofolate reductase (MTHFR) gene, a C to T substitution at nucleotide 677, is responsible for reduced MTHFR activity and associated with modestly increased plasma homocysteine concentrations. Since underlying maternal vascular disease increases the risk of pre-eclampsia, we had the working hypothesis that pre-eclampsia patients would have an increased T677 allele frequency compared with controls. The MTHFR genotypes were determined in 67 pre-eclampsia patients, 98 normal pregnant women, and 260 healthy adults by the PCR/RFLP method. The T677 allele and the genotype homozygous for the T677 allele were significantly increased in the pre-eclamptic group compared with the controls (p < 0.02 and p < 0.004, respectively). The data indicate that the T677 variant of the MTHFR gene is one of the genetic risk factors for pre-eclampsia.


Assuntos
Oxirredutases atuantes sobre Doadores de Grupo CH-NH/genética , Polimorfismo Genético , Pré-Eclâmpsia/enzimologia , Pré-Eclâmpsia/genética , Adulto , Alelos , Estudos de Casos e Controles , Feminino , Frequência do Gene , Genótipo , Homozigoto , Humanos , Metilenotetra-Hidrofolato Redutase (NADPH2) , Mutação Puntual , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Gravidez , Fatores de Risco
15.
Pediatr Radiol ; 27(12): 942-4, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9388288

RESUMO

We present an infant with the lethal Ellis-van Creveld syndrome who was diagnosed prenatally from the sonographic detection of a narrow chest, postaxial hexadactyly of the hands and feet, short limbs and a single atrium. The postnatal radiographic features of the skeleton favoured the diagnosis of Verma-Naumoff type or Saldino-Noonan type short rib-polydactyly syndrome (SRPS). We discuss the criteria for the differential diagnosis of patients with SRPS, which can be difficult because of the overlap of the various phenotypes.


Assuntos
Síndrome de Ellis-Van Creveld/diagnóstico por imagem , Átrios do Coração/diagnóstico por imagem , Osteocondrodisplasias/diagnóstico , Ultrassonografia Pré-Natal , Adulto , Diagnóstico Diferencial , Síndrome de Ellis-Van Creveld/patologia , Feminino , Átrios do Coração/anormalidades , Humanos , Recém-Nascido , Masculino , Osteocondrodisplasias/classificação , Osteocondrodisplasias/diagnóstico por imagem , Fenótipo , Gravidez , Radiografia
17.
Eur J Obstet Gynecol Reprod Biol ; 67(1): 65-7, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8789753

RESUMO

We present the first case of trisomy 18 in which echogenic fetal bowel was detected in the third trimester after normal echogenicity was documented during the second trimester. Fetal karyotyping should be considered in cases of increased echogenicity of the fetal lower abdomen in the second as well as the third trimester.


Assuntos
Cromossomos Humanos Par 18 , Intestinos/diagnóstico por imagem , Intestinos/embriologia , Trissomia , Ultrassonografia Pré-Natal , Anormalidades Múltiplas , Adulto , Feminino , Humanos , Gravidez
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