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1.
BJOG ; 128(9): 1497-1502, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33629515

RESUMO

OBJECTIVE: To investigate whether antenatal corticosteroid therapy improves neonatal and maternal outcomes in late preterm delivery. DESIGN: Population-based retrospective study. SETTING: The linkages of Taiwan's National Health Insurance Research Database, National Birth Reporting Database, and the Taiwan Maternal and Child Health Database. POPULATION: All births at risk for late preterm deliveries in Taiwan between 2004 and 2011. METHODS: For every birth at risk for late preterm delivery, five controls randomly matched by maternal and gestational ages and birthweight were included. A conditional logistic regression analysis was applied for risk estimation, with births without corticosteroids as the reference group. Odds ratios were adjusted for caesarean section, parity, sex, gestational hypertension and gestational diabetes mellitus. MAIN OUTCOME MEASURES: Neonatal outcomes, maternal outcomes and the utilisation of healthcare services. RESULTS: The outcomes of 5745 women treated with corticosteroids between 34+0  weeks and 36+6  weeks of gestation were compared with those of 28 135 untreated controls. Compared with the controls, births from women administered corticosteroids reduced the need for continuous positive airway pressure, the number of neonatal intensive care unit admission, and the need for glucose administration, as well as the risk of neonatal respiratory distress, but increased the risk of neonatal sepsis and the number of outpatient visits. CONCLUSIONS: Antenatal corticosteroid therapy in women at risk of late preterm delivery may significantly reduce the need for respiratory support and glucose supply, and respiratory complication risk in neonates. TWEETABLE ABSTRACT: Antenatal corticosteroids in late preterm delivery reduced the risk of neonatal respiratory complications in Taiwan.


Assuntos
Corticosteroides/administração & dosagem , Nascimento Prematuro/tratamento farmacológico , Síndrome do Desconforto Respiratório do Recém-Nascido/prevenção & controle , Corticosteroides/efeitos adversos , Adulto , Estudos de Casos e Controles , Bases de Dados Factuais , Feminino , Humanos , Recém-Nascido , Masculino , Sepse Neonatal/epidemiologia , Gravidez , Nascimento Prematuro/epidemiologia , Síndrome do Desconforto Respiratório do Recém-Nascido/epidemiologia , Estudos Retrospectivos , Medição de Risco , Taiwan/epidemiologia
2.
J Intern Med ; 287(4): 373-394, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32107805

RESUMO

Over the past three decades, considerable effort has been dedicated to quantifying the pace of ageing yet identifying the most essential metrics of ageing remains challenging due to lack of comprehensive measurements and heterogeneity of the ageing processes. Most of the previously proposed metrics of ageing have been emerged from cross-sectional associations with chronological age and predictive accuracy of mortality, thus lacking a conceptual model of functional or phenotypic domains. Further, such models may be biased by selective attrition and are unable to address underlying biological constructs contributing to functional markers of age-related decline. Using longitudinal data from the Baltimore Longitudinal Study of Aging (BLSA), we propose a conceptual framework to identify metrics of ageing that may capture the hierarchical and temporal relationships between functional ageing, phenotypic ageing and biological ageing based on four hypothesized domains: body composition, energy regulation, homeostatic mechanisms and neurodegeneration/neuroplasticity. We explored the longitudinal trajectories of key variables within these phenotypes using linear mixed-effects models and more than 10 years of data. Understanding the longitudinal trajectories across these domains in the BLSA provides a reference for researchers, informs future refinement of the phenotypic ageing framework and establishes a solid foundation for future models of biological ageing.


Assuntos
Envelhecimento/patologia , Idoso , Idoso de 80 Anos ou mais , Baltimore , Composição Corporal , Metabolismo Energético , Feminino , Homeostase , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Sistema Nervoso/patologia , Plasticidade Neuronal , Fenótipo , Valores de Referência
3.
Andrologia ; 45(2): 140-4, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22703286

RESUMO

Structural rearrangement in the Y chromosome is closely involved in spermatogenesis. However, several Y chromosome variants may have no deleterious effects on male reproduction. Here, we report two cases of Y chromosomal duplication from incidental findings. Their FISH analysis revealed direct duplication of large segments of short and long arms of the Y chromosome. Nearly two intact Y chromosomes were carried in these two cases with normal phenotype.


Assuntos
Duplicação Cromossômica , Cromossomos Humanos Y , Aberrações dos Cromossomos Sexuais , Adulto , Duplicação Cromossômica/genética , Cromossomos Humanos Y/genética , Feminino , Humanos , Hibridização in Situ Fluorescente , Recém-Nascido , Cariótipo , Masculino , Linhagem , Fenótipo , Gravidez , Adulto Jovem
4.
Eur Respir J ; 37(5): 1226-36, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-20817708

RESUMO

This study is the first to analyse the soluble factors secreted by the bronchial epithelium after exposure to isophorone diisocyanate (IPDI) that are responsible for increasing migration and proliferation of primary normal human bronchial smooth muscle cells (BSMCs). We treated immortalised, nontumorigenic human bronchial epithelial cells (cell line BEAS-2B) and primary normal human bronchial epithelial cells (HBEC) with IPDI, and then collected the conditioned culture media (IPDI-BEAS-2B-CM and IPDI-HBEC-CM, respectively), which was added to BSMCs. Exposure of BEAS-2B cells and HBECs to IPDI increased interleukin (IL)-8 production. Culture of BSMCs with IPDI-BEAS-2B-CM and IPDI-HBEC-CM increased BSMC proliferation and migration, which are major features in asthma-related airway remodelling. Induction of BSMC proliferation and migration by IPDI-BEAS-2B-CM and IPDI-HBEC-CM was associated with increased focal adhesion kinase (FAK), Src, extracellular signal-regulated kinase (ERK)1/2 and AKT activation. Blocking FAK with a specific inhibitor significantly decreased BSMC migration and proliferation by inhibiting ERK1/2 activation. FAK and ERK1/2 inhibitor also decreased IPDI-BEAS-2B-CM-, IPDI-HBEC-CM- and recombinant human IL-8-mediated BSMC proliferation and migration, whereas blocking Rnd3 using small interfering RNA failed to affect BSMC proliferation, suggesting that Rnd3 was only involved in the regulation of BSMC migration. Our study suggests that inhibition of IL-8 or IL-8-mediated FAK/ERK/Rnd3 signalling is an attractive therapeutic target for IPDI-mediated asthma.


Assuntos
Interleucina-8/biossíntese , Interleucina-8/metabolismo , Isocianatos/farmacologia , Músculo Liso/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Brônquios/efeitos dos fármacos , Brônquios/metabolismo , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Inibidores Enzimáticos/farmacologia , Proteína-Tirosina Quinases de Adesão Focal/antagonistas & inibidores , Proteína-Tirosina Quinases de Adesão Focal/biossíntese , Humanos , Proteína Quinase 1 Ativada por Mitógeno/biossíntese , Proteína Quinase 3 Ativada por Mitógeno/biossíntese , Proteínas Proto-Oncogênicas c-akt/biossíntese , RNA Interferente Pequeno/farmacologia , Proteínas rho de Ligação ao GTP/antagonistas & inibidores , Proteínas rho de Ligação ao GTP/biossíntese , Quinases da Família src/biossíntese
5.
Int J Androl ; 34(5 Pt 2): e358-67, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21128978

RESUMO

We have previously identified novel testis-specific genes by microarray analysis of human testicular tissues. One of the novel genes is Male Germ Cells Rab GTPase- Activating Proteins (MgcRabGAP), which is characterized by the conserved RabGAP catalytic domain, TBC (Tre2/Bub2/Cdc16). RabGAPs are involved in various physiological processes (e.g. vesicular trafficking, cytoskeletal remodelling, cell migration, etc.) by inactivating Rab proteins. In this study, we found that MgcRabGAP transcripts are mainly expressed in the mouse and human testes. The MgcRabGAP protein is expressed in the elongating and elongated spermatids. Immunofluorescence assay of mouse germ cells showed that the protein expression is enriched at the edge of the acrosomal region, neck and annulus during spermiogenesis. This MgcRabGAP is co-localized with its candidate substrate Rab3A at the acrosome/acroplaxome and neck regions of spermatids. Meanwhile, MgcRabGAP is co-localized and interacts with ß-actin. In humans, the expression of MgcRabGAP is enriched at the stage of elongating spermatids. The amount of MGCRABGAP transcript is reduced in the testicular tissues of men with various types of spermatogenic defects. Considering that MGCRABGAP is exclusively expressed in post-meiotic male germ cells, the decreased transcript amount may be a phenomenon secondary to loss of germ cells in the testicular samples. Our finding strongly suggests that MgcRabGAP is involved in acrosome/acroplaxome formation and cytoskeletal reorganization via Rab activity during mammalian spermiogenesis.


Assuntos
Proteínas Ativadoras de GTPase/metabolismo , Espermátides/metabolismo , Proteína rab3A de Ligação ao GTP/metabolismo , Acrossomo/fisiologia , Sequência de Aminoácidos , Animais , Citoesqueleto/fisiologia , Proteínas Ativadoras de GTPase/química , Humanos , Infertilidade Masculina/fisiopatologia , Masculino , Camundongos , Proteínas dos Microfilamentos/química , Proteínas dos Microfilamentos/metabolismo , Dados de Sequência Molecular , Alinhamento de Sequência , Espermatogênese/fisiologia , Testículo/metabolismo
6.
Oncogene ; 36(6): 863-874, 2017 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-27499095

RESUMO

The mechanical characteristics presented in cancer microenvironment are known to have pivotal roles in cancer metastasis, which accounts for the leading cause of death from malignant tumors. However, while a uniformly distributed high interstitial fluid pressure (IFP) is a common feature in solid tumors, the effects of high IFP on the motility and invasiveness of cancer cells remain obscure. Using cell-culture devices that simulated increased IFP conditions by applying hydrostatic pressure (HP) ranging from 0 to 20 mm Hg to the cells, we found that the elevated HPs increased the migration speeds, invasiveness, cell volume, filopodial number and aquaporin-1 (AQP1), Snail and vinculin expression levels, as well as phosphorylation of caveolin-1 and extracellular signal-regulated kinase1/2 (ERK1/2), in the lung cancer cells CL1-5 and A549. The increases of migration speed and cell volume correlated temporally with the increase of AQP1 expression. The elevated HP-induced migration acceleration was hindered by AQP1 knockdown using small interfering RNA (siRNA) transfection. Inhibition of ERK1/2 phosphorylation using the mitogen-activated protein kinase kinase inhibitor PD98059 abrogated the elevated HP-induced AQP1 upregulation and migration acceleration in the cancer cells. Caveolin-1 knockdown by siRNA transfection attenuated the HP-induced, ERK1/2-depedent AQP1 upregulation and migration acceleration. Further biochemical studies revealed that the caveolin-1 activation-driven ERK1/2 signaling is mediated by Akt1/2 phosphorylation. By contrast, the elevated HPs had negligible effects on the migration speed and volume of normal bronchial epithelial cells. These results disclose a novel mechanism relating high IFP to the invasiveness of cancer cells and highlight potential targets to impede cancer spreading.


Assuntos
Aquaporinas/metabolismo , Caveolina 1/metabolismo , Neoplasias Pulmonares/metabolismo , Movimento Celular/fisiologia , Proliferação de Células , Humanos , Pressão Hidrostática , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/patologia , Sistema de Sinalização das MAP Quinases , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Transdução de Sinais , Regulação para Cima
7.
Oncogene ; 36(34): 4929-4942, 2017 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-28436951

RESUMO

Hypoxia plays a critical role during the evolution of malignant cells and tumour microenvironment (TME).Tumour-derived exosomes contain informative microRNAs involved in the interaction of cancer and stromal cells, thus contributing to tissue remodelling of tumour microenvironment. This study aims to clarify how hypoxia affects tumour angiogenesis through exosomes shed from lung cancer cells. Lung cancer cells produce more exosomes under hypoxic conditions than do parental cells under normoxic conditions. miR-23a was significantly upregulated in exosomes from lung cancer under hypoxic conditions. Exosomal miR-23a directly suppressed its target prolyl hydroxylase 1 and 2 (PHD1 and 2), leading to the accumulation of hypoxia-inducible factor-1 α (HIF-1 α) in endothelial cells. Consequently, hypoxic lung cancer cells enhanced angiogenesis by exosomes derived from hypoxic cancer under both normoxic and hypoxic conditions. In addition, exosomal miR-23a also inhibits tight junction protein ZO-1, thereby increasing vascular permeability and cancer transendothelial migration. Inhibition of miR-23a by inhibitor administration decreased angiogenesis and tumour growth in a mouse model. Furthermore, elevated levels of circulating miR-23a are found in the sera of lung cancer patients, and miR-23a levels are positively correlated with proangiogenic activities. Taken together, our study reveals the clinical relevance and prognostic value of cancer-derived exosomal miR-23a under hypoxic conditions, and investigates a unique intercellular communication, mediated by cancer-derived exosomes, which modulates tumour vasculature.


Assuntos
Permeabilidade Capilar/fisiologia , Exossomos/metabolismo , Neoplasias Pulmonares/metabolismo , MicroRNAs/metabolismo , Neovascularização Patológica/metabolismo , Prolil Hidroxilases/metabolismo , Proteína da Zônula de Oclusão-1/metabolismo , Animais , Hipóxia Celular/fisiologia , Linhagem Celular , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Hipóxia/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas de Junções Íntimas/metabolismo
8.
Food Chem Toxicol ; 44(5): 704-13, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16307839

RESUMO

Chalcones are discussed to represent cancer preventive food components in a human diet that is rich in fruits and vegetables. In this study, we examined chalcone (1,3-diphenyl-2-propenone) for its effect on proliferation in human breast cancer cell lines, MCF-7 and MDA-MB-231. The results showed that chalcone inhibited the proliferation of MCF-7 and MDA-MB-231 by inducing apoptosis and blocking cell cycle progression in the G2/M phase. Immunoblot assay showed that chalcone significantly decreased the expression of cyclin B1, cyclin A and Cdc2 protein, as well as increased the expression of p21 and p27 in a p53-independent manner, contributing to cell cycle arrest. An enhancement in Fas/APO-1 and its two form ligands, membrane-bound Fas ligand (mFasL) and soluble Fas ligand (sFasL), was responsible for the apoptotic effect induced by chalcone. In addition, chalcone also triggered the mitochondrial apoptotic signaling by increasing the amount of Bax and Bak and reducing the level of Bcl-2 and Bcl-X(L), and subsequently activated caspase-9 in MCF-7 and MDA-MB-231 cells. Taken together, our study suggests that the blockade of cell cycle progression and initiation of cell apoptotic system may participate in the antiproliferative activity of chalcone in human breast cancer cells.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Chalcona/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/prevenção & controle , Caspase 9 , Caspases/metabolismo , Ciclina A/metabolismo , Ciclina B/metabolismo , Ciclina B1 , Relação Dose-Resposta a Droga , Proteína Ligante Fas , Fase G2/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Immunoblotting , Glicoproteínas de Membrana/metabolismo , Mitose/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Células Tumorais Cultivadas , Fatores de Necrose Tumoral/metabolismo , Proteína bcl-X/metabolismo
9.
Food Chem Toxicol ; 43(2): 315-23, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15621344

RESUMO

Prodelphinidin B-2 3'-O-gallate, a proanthocyanidin gallate isolated from green tea leaf, was investigated for its anti-proliferative activity in human non-small cell lung cancer A549 cells. The results showed that prodelphinidin B-2 3'-O-gallate inhibited the proliferation of A549 cells with no detectable toxic effects on normal WI-38 cells as measured by the XTT assay. Flow cytometric analysis showed that prodelphinidin B-2 3'-O-gallate blocked cell cycle progression in the G0/G1 phase. In addition, prodelphinidin B-2 3'-O-gallate effectively induced A549 cell apoptosis as determined by assessing the nucleosome level in cytoplasm. Enzyme-linked immunosorbent assay showed that the G0/G1 phase arrest is due to p53-independent induction of p21/WAF1. An enhancement in Fas/APO-1 and its two form ligands, membrane-bound Fas ligand (mFasL) and soluble Fas ligand (sFasL), might be responsible for the apoptotic effect induced by prodelphinidin B-2 3'-O-gallate. We suggested that prodelphinidin B-2 3'-O-gallate's activities might be potentially contribute to its overall chemopreventive effects against lung cancer, and can possibly be considered for future therapeutic application.


Assuntos
Antocianinas/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Chá/química , Proteína Supressora de Tumor p53/metabolismo , Antineoplásicos Fitogênicos/uso terapêutico , Divisão Celular/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Proteína Ligante Fas , Citometria de Fluxo , Fase G1 , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Glicoproteínas de Membrana , Fase de Repouso do Ciclo Celular , Células Tumorais Cultivadas
10.
Oncogene ; 34(31): 4056-68, 2015 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-25381822

RESUMO

Lung cancer is the leading cause of cancer death worldwide, with metastasis underlying majority of related deaths. Angiomotin (AMOT), a scaffold protein, has been shown to interact with oncogenic Yes-associated protein/transcriptional co-activator with a PDZ-binding motif (YAP/TAZ) proteins, suggesting a potential role in tumor progression. However, the functional role of AMOT in lung cancer remains unknown. This study aimed to identify the patho-physiological characteristics of AMOT in lung cancer progression. Results revealed that AMOT expression was significantly decreased in clinical lung cancer specimens. Knockdown of AMOT in a low metastatic CL1-0 lung cancer cell line initiated cancer proliferation, migration, invasion and epithelial-mesenchymal transition. The trigger of cancer progression caused by AMOT loss was transduced by decreased cytoplasmic sequestration and increased nuclear translocation of oncogenic co-activators YAP/TAZ, leading to increased expression of the growth factor, Cyr61. Tumor promotion by AMOT knockdown was reversed when YAP/TAZ or Cyr61 was absent. Further, AMOT knockdown increased the growth and spread of Lewis lung carcinoma in vivo. These findings suggest that AMOT is a crucial suppressor of lung cancer metastasis and highlight its critical role as a tumor suppressor and its potential as a prognostic biomarker and therapeutic target for lung cancer.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adenocarcinoma/patologia , Proteína Rica em Cisteína 61/genética , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Neoplasias Pulmonares/patologia , Proteínas dos Microfilamentos/fisiologia , Fosfoproteínas/metabolismo , Fatores de Transcrição/metabolismo , Aciltransferases , Adenocarcinoma/genética , Adenocarcinoma de Pulmão , Angiomotinas , Animais , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Proteína Rica em Cisteína 61/metabolismo , Progressão da Doença , Regulação para Baixo/genética , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Neoplasias Pulmonares/genética , Proteínas de Membrana/metabolismo , Proteínas de Membrana/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Nus , Proteínas dos Microfilamentos/metabolismo , Ligação Proteica , Proteínas de Sinalização YAP
11.
Am J Med Genet ; 55(3): 279-84, 1995 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-7726223

RESUMO

We describe a nonconsanguineous couple whose 3 successive pregnancies, including one pair of twins, led to the birth of 4 infants with short rib-polydactyly syndrome (SRPS). Flat face, hypoplastic thorax, short limbs and ribs, polydactyly, absence of penis, and death after birth were noted in the first affected male baby. The affected female twins were detected prenatally by ultrasonography and had the same characteristics, but milder than the previous one. Serial measurements of the thoracic circumference and the 4 limbs were obtained by ultrasound, and showed progressively decreased ratio of thoracic to abdominal circumference and shortness of the limbs. The last male baby also had a similar but variable expression in prenatal ultrasonography.


Assuntos
Doenças Fetais/diagnóstico por imagem , Síndrome de Costela Curta e Polidactilia/diagnóstico por imagem , Ultrassonografia Pré-Natal , Adulto , Doenças em Gêmeos , Evolução Fatal , Feminino , Humanos , Recém-Nascido , Masculino , Gravidez
12.
Obstet Gynecol ; 94(3): 464-8, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10472878

RESUMO

OBJECTIVE: To assess the frequencies of nucleated red blood cells (RBCs) in maternal blood during different stages of gestation and postpartum. METHODS: Peripheral venous blood samples were collected longitudinally from 38 pregnant women from the first trimester to 3 months postpartum. Nucleated RBCs were isolated by using a triple-density gradient with Histopaque (Sigma Diagnostics, St. Louis, MO) and identified by Kleihauser-Betke acid stain. RESULTS: The number of nucleated RBCs steadily increased from 3.9 (standard error 0.6) per 10(7) nucleated cells in early gestation (6-10 weeks) to 112.0 (standard error 7.5) per 10(7) nucleated cells near term and decreased rapidly after delivery. The number of nucleated RBCs was not related to the gender of the fetus or the ABO blood type compatibility between the mother and fetus. CONCLUSION: The number of nucleated RBCs in the maternal blood increase progressively throughout pregnancy, with some variation from subject to subject.


Assuntos
Eritrócitos/patologia , Gravidez/sangue , Adulto , Contagem de Eritrócitos , Feminino , Humanos , Estudos Longitudinais
13.
Obstet Gynecol ; 77(3): 478-82, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1992421

RESUMO

Doppler velocimetry of the umbilical and intraplacental fetal arteries was studied by color flow mapping in 39 normal pregnancies. The systolic-diastolic ratio (S/D) and pulsatility index of the intraplacental fetal artery downstream to the umbilical artery decreased significantly with advancing gestational age, and its S/Ds were persistently lower than those of the umbilical artery. The difference in the S/D between the umbilical artery and its intraplacental downstream branches decreased with advancing gestational age and approached zero as the pregnancy progressed to term. We conclude that intraplacental fetal arteries, possibly fetal arteries in main stem villi, can be imaged by color flow mapping and that there is a significant "resistance gradient" between the intraplacental fetal artery and the umbilical artery. Intraplacental fetal artery velocimetry using color flow mapping may give further insights into the umbilical-placental circulation.


Assuntos
Placenta/irrigação sanguínea , Placenta/diagnóstico por imagem , Adulto , Artérias/diagnóstico por imagem , Velocidade do Fluxo Sanguíneo , Feminino , Feto/irrigação sanguínea , Idade Gestacional , Humanos , Gravidez , Análise de Regressão , Ultrassonografia Pré-Natal , Artérias Umbilicais/diagnóstico por imagem
14.
Obstet Gynecol ; 74(5): 722-5, 1989 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2812648

RESUMO

Funipuncture offers direct access to the fetal circulation. The blood gas and acid-base status of the fetus can be studied, and fetal hypoxia and acidosis can be diagnosed directly. To establish normal ranges of fetal blood gas and acid-base status, we analyzed umbilical venous blood samples obtained by funipuncture from 62 normal fetuses (20-35 weeks). These fetuses were studied because of suspected fetal diseases and were subsequently proved to be normal by the fetal blood examinations. Umbilical vein pH and pO2 decreased whereas pCO2 and bicarbonate increased with gestational age. The umbilical vein base excess did not correlate with gestational duration, but oxygen saturation tended to decrease with gestational age. Twenty hydropic fetuses with Bart hemoglobinopathy were also studied; they were found to be more acidotic, hypoxic, and hypercarbic than normal fetuses.


Assuntos
Equilíbrio Ácido-Base , Sangue Fetal/análise , Hemoglobinopatias/sangue , Hemoglobinas Anormais/análise , Hidropisia Fetal/sangue , Gasometria , Feminino , Doenças Fetais/sangue , Humanos , Concentração de Íons de Hidrogênio , Gravidez , Valores de Referência
15.
Diagn Mol Pathol ; 8(3): 152-6, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10565687

RESUMO

Fragile X syndrome (FXS) is the most common hereditary form of mental retardation. Molecular analysis of the FMR1 gene has now been applied to diagnosis and carrier detection. Because treatment is not feasible, prevention of FXS by prenatal diagnosis of carrier women early during pregnancy is important. The aim of this pilot study was to ascertain the prevalence of mutant FMR1 gene in normal population of Taiwan and to evaluate the efficacy of a betaine-based polymerase chain reaction (PCR) and nonradioactive Southern blot assays. The DNA was randomly and anonymously collected from 100 women and 100 men. The results showed 62% of the women were heterozygous for the CGG-repeat size in FMR1 gene. One of 300 X chromosomes in this study showed premutation, with 95 CGG repeats. All other chromosomes have CGG repeats ranging from 19 to 52, with eight chromosomes (3%) having more than 40 CGG repeats. The most prevalent allele has 29 repeats (48.1%), followed by 30 (24.0%) and 36 (9.5%), respectively. The results of this study reconfirmed previous reports that the prevalent FMR1 CGG repeat alleles in Chinese population are different from that of other populations. However, the prevalence of premutation gene seems to be comparable among them. The betaine-based PCR could minimize the intrinsic problem of preferential amplification and may reliably determine the different allele repeats in heterozygous females. This nonradioactive Southern blot protocol is safe, efficient, and inexpensive. However, further technical improvement may be needed to be more cost-effective for a wide screening of all pregnant women.


Assuntos
Síndrome do Cromossomo X Frágil/genética , Testes Genéticos/métodos , Mutação , Proteínas do Tecido Nervoso/genética , Proteínas de Ligação a RNA , Southern Blotting , DNA/sangue , Feminino , Proteína do X Frágil da Deficiência Intelectual , Síndrome do Cromossomo X Frágil/diagnóstico , Síndrome do Cromossomo X Frágil/epidemiologia , Triagem de Portadores Genéticos , Humanos , Masculino , Projetos Piloto , Reação em Cadeia da Polimerase , Gravidez , Diagnóstico Pré-Natal , Prevalência , Taiwan/epidemiologia , Repetições de Trinucleotídeos , Cromossomo X
16.
Diagn Mol Pathol ; 10(1): 34-40, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11277393

RESUMO

Fragile X syndrome (FXS) is the most common form of familial mental retardation (MR). It is caused by the expansion of the CGG repeat in the FMR1 gene on the X chromosome. To date, FXS is not treatable, but can be prevented by prenatal genetic examination. Identifying women who carry a full mutation or premutation FMR1 gene is thus very important, and can be done by tracing family members of FXS subjects. However, most of the FXS subjects in Taiwan as well as those in many other countries have not been identified. In this study the authors attempt to develop reliable and inexpensive tests suitable for a large-scale screen of subjects with MR for FXS. Together with their previous study, a total of 311 male and 160 female subjects with MR were screened with nonradioactive Southern blot assay using mixed deoxyribonucleic acid from three subjects of the same sex. From these subjects, nine male subjects and one female FXS subject were diagnosed. All male subjects were also screened with nonradioactive polymerase chain reaction (PCR). These nine male FXS subjects were also detected on the basis of PCR amplification failure. No false-negative results were discerned. The PCR procedure was simplified further by combining it with an analysis of a blood spot on filter paper, which is a much simpler and cheaper method for sample collection and DNA preparation. This method was then used to screen 104 boys with MR. Two of them were suspected, and later confirmed with Southern blot assay, as subjects with FXS. This study suggests that simple PCR combined with blood spot analysis could be a reliable, inexpensive test that is feasible for a large-scale screening of male subjects with MR for FXS. However, Southern blot assay with mixed deoxyribonucleic acid is appropriate for screening female subjects. Based on this strategy, most FXS subjects could be identified easily for further management.


Assuntos
Síndrome do Cromossomo X Frágil/genética , Triagem de Portadores Genéticos/métodos , Testes Genéticos/métodos , Deficiência Intelectual/genética , Proteínas de Ligação a RNA , Southern Blotting , Criança , Pré-Escolar , DNA/análise , Análise Mutacional de DNA , Feminino , Proteína do X Frágil da Deficiência Intelectual , Síndrome do Cromossomo X Frágil/sangue , Síndrome do Cromossomo X Frágil/epidemiologia , Humanos , Lactente , Recém-Nascido , Deficiência Intelectual/sangue , Deficiência Intelectual/epidemiologia , Masculino , Mutação , Proteínas do Tecido Nervoso/sangue , Reação em Cadeia da Polimerase , Taiwan/epidemiologia
17.
Ultrasound Med Biol ; 27(9): 1275-84, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11597369

RESUMO

Elastic properties of tendon were assessed by two different approaches. Six fresh bovine Achilles tendon specimens were used. The first approach directly measured Young's modulus along the transverse direction (E(perpendicular)) and the longitudinal direction (E(parallel)), using a cyclic compression-relaxation method. Young's moduli were derived based on the measured strain and stress values. The ratio of E(parallel): E(perpendicular) at smaller strains was around 4 and decreased to 0.6 approximately 1.1 at larger strains. The second approach assumed that tendons are transversely isotropic. Three observable second-order elastic stiffness constants (c(11), c(13) and c(33)) were obtained by sound speed measurements along various propagation directions. The measured elastic stiffness constants were also correlated with results from the first approach. It was shown that the transverse isotropy assumption was valid at small strains. However, a significant discrepancy existed between the two approaches. The discrepancy was primarily due to viscoelasticity associated with the first approach.


Assuntos
Tendão do Calcâneo/diagnóstico por imagem , Tendão do Calcâneo/fisiopatologia , Entorses e Distensões/diagnóstico por imagem , Entorses e Distensões/fisiopatologia , Tendão do Calcâneo/lesões , Animais , Anisotropia , Bovinos , Técnicas de Cultura , Modelos Animais de Doenças , Elasticidade , Contração Muscular/fisiologia , Relaxamento Muscular/fisiologia , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/fisiopatologia , Estresse Mecânico , Transdutores , Ultrassonografia
18.
Ultrasound Med Biol ; 25(8): 1241-50, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10576267

RESUMO

Axial components of tendons' transverse strain fields were successfully measured in vitro by ultrasound. Achilles tendons of New Zealand white rabbits were used. Tendon inflammation was simulated by artificially inducing ischemia. Strain measurements were also correlated with conventional B-mode sonograms and histological micrographs. Results showed that strain measurements had reasonable agreement with histological examinations and provided better tissue differentiation than conventional B-mode imaging. For a given tendon, the strain values corresponding to different tissue layers were easily differentiated with an elastographic contrast-to-noise ratio ranging from 17 to 43 dB. Such differences, however, were not always present in the sonograms. Therefore, ultrasonic strain imaging may be a useful tool for assessing tendon disorders during the rehabilitation process.


Assuntos
Tendão do Calcâneo/diagnóstico por imagem , Tendão do Calcâneo/fisiologia , Tendão do Calcâneo/fisiopatologia , Animais , Fenômenos Biomecânicos , Elasticidade , Imagens de Fantasmas , Coelhos , Tendinopatia/diagnóstico por imagem , Tendinopatia/fisiopatologia , Ultrassonografia
19.
Int J Gynaecol Obstet ; 48(3): 295-8, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7781873

RESUMO

We present a case of prenatally diagnosed mediastinal cystic hygroma with spontaneous resolution. To our knowledge, this is only the second case report of mediastinal cystic hygroma diagnosed prenatally, and the first one with spontaneous resolution perinatally. Our case shows that, in the absence of hydrops fetalis, mediastinal cystic hygroma in a fetus with normal karyotype can be associated with a normal outcome. Therefore we recommend fetal karyotyping, a careful search for other anomalies and close sonographic follow-up in such cases.


Assuntos
Doenças Fetais , Linfangioma Cístico , Neoplasias do Mediastino , Regressão Neoplásica Espontânea , Adulto , Feminino , Doenças Fetais/diagnóstico por imagem , Doenças Fetais/genética , Humanos , Cariotipagem , Linfangioma Cístico/diagnóstico por imagem , Linfangioma Cístico/genética , Neoplasias do Mediastino/diagnóstico por imagem , Neoplasias do Mediastino/genética , Gravidez , Ultrassonografia Pré-Natal
20.
J Formos Med Assoc ; 98(6): 433-9, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10443068

RESUMO

This study was designed to address the feasibility of detection of fetal cells with chromosome abnormalities in maternal blood. Peripheral venous blood samples were collected from 150 pregnant women 1 day to 8 weeks before invasive examinations (amniocentesis, chorionic villus sampling, or fetal blood sampling). Fetal nucleated red blood cells were isolated by using a triple-density gradient followed by magnetic-activated cell sorting to select CD71 cells. Fluorescence in situ hybridization (FISH) with probes specific for chromosomes X, Y, 13, 18, and 21 was used to detect fetal cells from aneuploid pregnancies. The hybridization efficiency was greater than 98% for each probe in normal controls, and approximately 20% of all cells failed to hybridize after magnetic-activated cell sorting. Of the 10 aneuploid pregnancies identified with invasive procedures, trisomic fetal cells were identified in eight. The frequency of fetal cells in the sorted specimens ranged from 0 to 223 per 10,000 maternal nucleated cells. Although the aneuploid fetal cells could be successfully detected in eight of 10 patients in the current study, the existence of some limiting factors, such as scarcity of fetal cells and poor hybridization efficiency of FISH, raises questions about its clinical suitability for routine use.


Assuntos
Aneuploidia , Aberrações Cromossômicas/diagnóstico , Sangue Fetal/citologia , Diagnóstico Pré-Natal/métodos , Transtornos Cromossômicos , Feminino , Humanos , Hibridização in Situ Fluorescente , Masculino , Troca Materno-Fetal , Valor Preditivo dos Testes , Gravidez
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