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1.
Ecotoxicol Environ Saf ; 200: 110772, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32464444

RESUMO

Recently two-dimensional nanomaterials, such as graphene and molybdenum disulfide (MoS2), have received much attention as adsorbent materials for the effective removal of organic contaminants. MoS2 is attracting attention, not only for its chemical-physical properties, but also for its wide availability in nature as a constituent of molybdenite. The aim of this investigation was to assess the effects of different MoS2 concentrations (5 × 10-1, 5 × 10-2 and 5 × 10-3 mg/ml) on the embryonated eggs of Gallus gallus domesticus, according to Beck method. We evaluated the toxic effect of the MoS2 powder purchased at Sigma-Aldrich indicated as "received" and MoS2 powder treated via mechanical milling indicated as "ball mille". Subsequently, the embryos were sacrificed at different times of embryonic development (11th, 15th and 19th day after incubation) in order to evaluate their embryotoxic and teratogenic effects. The alterations of the embryonic development were studied by morphological and immunohistochemical analysis of the tissues. The results obtained have shown the toxicity of both powders of MoS2 with a high percentage of deaths and growth delays. Moreover, the immunohistochemical analysis performed on several tissue sections showed a strong positivity to the anti-metallothionein1 antibody only for the erythrocytes.


Assuntos
Dissulfetos/química , Dissulfetos/toxicidade , Desenvolvimento Embrionário/efeitos dos fármacos , Molibdênio/química , Molibdênio/toxicidade , Nanopartículas/química , Nanopartículas/toxicidade , Animais , Embrião de Galinha , Relação Dose-Resposta a Droga , Grafite/química , Coração/efeitos dos fármacos , Coração/embriologia , Fígado/efeitos dos fármacos , Fígado/embriologia , Fígado/patologia , Pulmão/efeitos dos fármacos , Pulmão/embriologia , Pulmão/patologia , Tamanho da Partícula , Propriedades de Superfície
2.
Cold Spring Harb Protoc ; 2020(11)2020 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-32404313

RESUMO

Failure to predict drug-induced toxicity reactions is a major problem contributing to a high attrition rate and tremendous cost in drug development. Drug screening in X. laevis embryos is high-throughput relative to screening in rodents, potentially making them ideal for this use. Xenopus embryos have been used as a toxicity model in the frog embryo teratogenesis assay on Xenopus (FETAX) for the early stages of drug safety evaluation. We previously developed compound-screening methods using Xenopus embryos and believe they could be used for in vitro drug-induced toxicity safety assessment before expensive preclinical trials in mammals. Specifically, Xenopus embryos could help predict drug-induced hepatotoxicity and consequently aid lead candidate prioritization. Here we present methods, which we have modified for use on Xenopus embryos, to help measure the potential for a drug to induce liver toxicity. One such method examines the release of the liver-specific microRNA (miRNA) miR-122 from the liver into the vasculature as a result of hepatocellular damage, which could be due to drug-induced acute liver injury. Paracetamol, a known hepatotoxin at high doses, can be used as a positive control. We previously showed that some of the phenotypes of mammalian paracetamol overdose are reflected in Xenopus embryos. Consequently, we have also included here a method that measures the concentration of free glutathione (GSH), which is an indicator of paracetamol-induced liver injury. These methods can be used as part of a panel of protocols to help predict the hepatoxicity of a drug at an early stage in drug development.


Assuntos
Anormalidades Induzidas por Medicamentos/diagnóstico , Bioensaio/métodos , Doença Hepática Induzida por Substâncias e Drogas/diagnóstico , Embrião não Mamífero/efeitos dos fármacos , Xenopus laevis/embriologia , Anormalidades Induzidas por Medicamentos/genética , Anormalidades Induzidas por Medicamentos/metabolismo , Animais , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Avaliação Pré-Clínica de Medicamentos/métodos , Embrião não Mamífero/metabolismo , Fígado/efeitos dos fármacos , Fígado/embriologia , Fígado/metabolismo , MicroRNAs/genética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Testes de Toxicidade/métodos , Xenopus laevis/genética , Xenopus laevis/metabolismo
3.
Food Chem Toxicol ; 129: 424-433, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31077736

RESUMO

Formation of DNA adducts by five alkenylbenzenes, safrole, methyl eugenol, eugenol, and asarone with either α- or ß-conformation, was analyzed in fetal avian livers in two in ovo models. DNA reactivity of the carcinogens safrole and methyl eugenol was previously demonstrated in the turkey egg model, whereas non-genotoxic eugenol was negative. In the current study, alkenylbenzenes were also tested in the chicken egg model. Injections with alkenylbenzenes were administered to fertilized turkey or chicken eggs for three consecutive days. Three hours after the last injection, liver samples were evaluated for DNA adduct formation using the 32P-nucleotide postlabeling assay. DNA samples from turkey livers were also analyzed for adducts using mass spectrometry. In both species, genotoxic alkenylbenzenes safrole, methyl eugenol, α- and ß-asarone produced DNA adducts, the presence and nature of which, with exception of safrole, were confirmed by mass spectrometry, validating the sensitivity of the 32P-postlabeling assay. Overall, the results of testing were congruent between fetal turkey and chicken livers, confirming that these organisms can be used interchangeably. Moreover, data obtained in both models is comparable to genotoxicity findings in other species, supporting the usefulness of avian models for the assessment of genotoxicity as a potential alternative to animal models.


Assuntos
Derivados de Benzeno/toxicidade , Adutos de DNA/química , Fígado/efeitos dos fármacos , Animais , Derivados de Benzeno/metabolismo , Galinhas , Feto/efeitos dos fármacos , Fígado/embriologia , Fígado/metabolismo , Relação Estrutura-Atividade , Perus
4.
Prenat Diagn ; 38(9): 629-637, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29924391

RESUMO

Congenital diaphragmatic hernia is a rare disease associated with high mortality and morbidity. Antenatal ultrasound screening identifies more than 70% of cases, providing the opportunity for in utero referral to a tertiary care center for expert assessment and perinatal management. Additional genetic and morphologic assessment may be used to rule out associated anomalies. In isolated cases, the outcome may be predicted prenatally by medical imaging. The combination of lung size and liver herniation is a widely accepted method to stratify fetuses into groups with an increasing degree of pulmonary hypoplasia and corresponding mortality rates. Ultrasound measurement of the observed to expected lung-to-head ratio (o/e LHR) is most widely used. The o/e LHR is an independent predictor of survival and short-term morbidity. Finally, evaluation of stomach position has recently been introduced as an indirect method to estimate severity of the disease in left-sided defects, as it has been shown to correlate with the proportion of intrathoracic liver. Herein, we propose a protocol for the standardized ultrasound assessment of fetuses with isolated CDH and individualized prediction of neonatal outcome.


Assuntos
Hérnias Diafragmáticas Congênitas/diagnóstico por imagem , Ultrassonografia Pré-Natal/normas , Europa (Continente) , Feminino , Testes Genéticos , Hérnias Diafragmáticas Congênitas/genética , Humanos , Fígado/diagnóstico por imagem , Fígado/embriologia , Pulmão/diagnóstico por imagem , Pulmão/embriologia , Imageamento por Ressonância Magnética , Gravidez , Resultado da Gravidez , Doenças Raras/diagnóstico por imagem , Doenças Raras/embriologia , Valores de Referência , Estômago/diagnóstico por imagem , Estômago/embriologia , Ultrassonografia Pré-Natal/métodos
5.
Jpn J Radiol ; 36(7): 444-449, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29767297

RESUMO

PURPOSE: We evaluated the associations between gestational age (GA) and lung-to-liver signal intensity ratio (LLSIR) and fetal lung volume (FLV) using magnetic resonance imaging (MRI). Moreover, we evaluated the reproducibility of these measurements. MATERIALS AND METHODS: LLSIR and FLV were measured using single-shot fast spin-echo MRI in 88 consecutive fetuses. The Spearman test was used to assess the relationships between (1) LLSIR and GA, and (2) FLV and GA in 81 fetuses without lung abnormalities. Intra- and inter-observer reliabilities were assessed using intra-class correlation coefficients (ICCs). RESULTS: Overall, GA and LLSIR were significantly correlated (r = 0.62, p < 0.001). However, GA and LLSIR were only significantly correlated during the third trimester (before third trimester: r = 0.39, p = 0.08; during third trimester: r = 0.46, p < 0.001). Overall, GA and FLV were significantly correlated (r = 0.72, p < 0.001). FLV was significantly correlated with GA before (r = 0.86, p < 0.001) and during the third trimester (r = 0.47, p < 0.001). All ICCs were above 0.90. CONCLUSIONS: LLSIR and FLV are useful for the assessment of fetal lung maturity and are highly reproducible. Before the third trimester, FLV is more suitable than LLSIR for the evaluation of fetal lung maturity.


Assuntos
Pulmão/anatomia & histologia , Pulmão/embriologia , Imageamento por Ressonância Magnética/métodos , Feminino , Idade Gestacional , Humanos , Fígado/anatomia & histologia , Fígado/diagnóstico por imagem , Fígado/embriologia , Pulmão/diagnóstico por imagem , Tamanho do Órgão , Gravidez , Reprodutibilidade dos Testes , Estudos Retrospectivos
6.
Toxicol Appl Pharmacol ; 354: 115-125, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29630969

RESUMO

Superfund sites often consist of complex mixtures of polycyclic aromatic hydrocarbons (PAHs). It is widely recognized that PAHs pose risks to human and environmental health, but the risks posed by exposure to PAH mixtures are unclear. We constructed an environmentally relevant PAH mixture with the top 10 most prevalent PAHs (SM10) from a Superfund site derived from environmental passive sampling data. Using the zebrafish model, we measured body burden at 48 hours post fertilization (hpf) and evaluated the developmental and neurotoxicity of SM10 and the 10 individual constituents at 24 hours post fertilization (hpf) and 5 days post fertilization (dpf). Zebrafish embryos were exposed from 6 to 120 hpf to (1) the SM10 mixture, (2) a variety of individual PAHs: pyrene, fluoranthene, retene, benzo[a]anthracene, chrysene, naphthalene, acenaphthene, phenanthrene, fluorene, and 2-methylnaphthalene. We demonstrated that SM10 and only 3 of the individual PAHs were developmentally toxic. Subsequently, we constructed and exposed developing zebrafish to two sub-mixtures: SM3 (comprised of 3 of the developmentally toxicity PAHs) and SM7 (7 non-developmentally toxic PAHs). We found that the SM3 toxicity profile was similar to SM10, and SM7 unexpectedly elicited developmental toxicity unlike that seen with its individual components. The results demonstrated that the overall developmental toxicity in the mixtures could be explained using the general concentration addition model. To determine if exposures activated the AHR pathway, spatial expression of CYP1A was evaluated in the 10 individual PAHs and the 3 mixtures at 5 dpf. Results showed activation of AHR in the liver and vasculature for the mixtures and some individual PAHs. Embryos exposed to SM10 during development and raised in chemical-free water into adulthood exhibited decreased learning and responses to startle stimulus indicating that developmental SM10 exposures affect neurobehavior. Collectively, these results exemplify the utility of zebrafish to investigate the developmental and neurotoxicity of complex mixtures.


Assuntos
Poluentes Ambientais/toxicidade , Sistema Nervoso/efeitos dos fármacos , Síndromes Neurotóxicas/etiologia , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Peixe-Zebra/embriologia , Animais , Hidrocarboneto de Aril Hidroxilases/biossíntese , Comportamento Animal/efeitos dos fármacos , Carga Corporal (Radioterapia) , Relação Dose-Resposta a Droga , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Indução Enzimática , Aprendizagem/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/embriologia , Fígado/enzimologia , Sistema Nervoso/embriologia , Sistema Nervoso/fisiopatologia , Síndromes Neurotóxicas/embriologia , Síndromes Neurotóxicas/fisiopatologia , Receptores de Hidrocarboneto Arílico/agonistas , Receptores de Hidrocarboneto Arílico/metabolismo , Reflexo de Sobressalto/efeitos dos fármacos , Medição de Risco , Peixe-Zebra/metabolismo
7.
Ultrasound Obstet Gynecol ; 51(2): 214-218, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28078737

RESUMO

OBJECTIVES: To introduce a new sonographic marker of intrathoracic liver herniation in fetuses with left-sided congenital diaphragmatic hernia (CDH). METHODS: In a consecutive series of fetuses with isolated CDH, an ultrasound volume of the fetal abdomen was acquired. On this volume, offline calculation of the angle formed by the midline of the abdomen (joining the center of the vertebral body to the abdominal insertion of the umbilical cord) and a second line joining the center of the vertebral body to the intra-abdominal convexity of the umbilical vein was carried out to give the umbilical vein deviation angle (UVDA). The UVDA was measured in a group of normal fetuses selected as controls. At follow-up, the presence of liver herniation was investigated in all cases of CDH. UVDA values were compared between the CDH group and controls, and between CDH 'liver-up' vs 'liver-down' cases. A receiver-operating characteristics (ROC) curve was constructed to identify a cut-off value of the UVDA with the highest accuracy in predicting liver herniation in the CDH group. RESULTS: Between 2009 and 2015, 22 cases of left-sided CDH were included in the study group, of which nine cases had liver herniation. Eighty-eight normal fetuses were recruited as controls. The UVDA was significantly higher in the cases vs controls (15.25 ± 7.91° vs 7.68 ± 1.55°; P < 0.0001). Moreover, the UVDA was significantly increased in CDH fetuses with liver-up vs liver-down (21.77 ± 8.79° vs 10.75 ± 2.10°; P < 0.0001). On ROC curve analysis the UVDA showed good prediction of liver herniation (area under the ROC curve, 0.94; P < 0.0001) with the best cut-off of 15.2°, yielding a sensitivity of 89% and a specificity of 100% (P < 0.0001). CONCLUSIONS: In fetuses with CDH, umbilical vein bowing may be quantified by measuring the UVDA using three-dimensional ultrasound. This sonographic marker seems to be an accurate predictor of liver herniation in left-sided CDH. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Ecocardiografia Tridimensional , Doenças Fetais/diagnóstico por imagem , Hérnias Diafragmáticas Congênitas/diagnóstico por imagem , Hepatopatias/diagnóstico por imagem , Fígado/diagnóstico por imagem , Ultrassonografia Pré-Natal , Adulto , Feminino , Doenças Fetais/patologia , Testes Genéticos , Idade Gestacional , Hérnias Diafragmáticas Congênitas/embriologia , Hérnias Diafragmáticas Congênitas/patologia , Humanos , Itália , Fígado/embriologia , Hepatopatias/embriologia , Hepatopatias/patologia , Gravidez , Estudos Prospectivos , Curva ROC , Veias Umbilicais/anormalidades , Veias Umbilicais/diagnóstico por imagem
8.
Cereb Cortex ; 28(5): 1783-1793, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28407057

RESUMO

Thyroid hormones (THs, T4 and the transcriptionally active hormone T3) play an essential role in neurodevelopment; however, the mechanisms underlying T3 brain delivery during mice fetal development are not well known. This work has explored the sources of brain T3 during mice fetal development using biochemical, anatomical, and molecular approaches. The findings revealed that during late gestation, a large amount of fetal brain T4 is of maternal origin. Also, in the developing mouse brain, fetal T3 content is regulated through the conversion of T4 into T3 by type-2 deiodinase (D2) activity, which is present from earlier prenatal stages. Additionally, D2 activity was found to be essential to mediate expression of T3-dependent genes in the cerebral cortex, and also necessary to generate the transient cerebral cortex hyperthyroidism present in mice lacking the TH transporter Monocarboxylate transporter 8. Notably, the gene encoding for D2 (Dio2) was mainly expressed at the blood-cerebrospinal fluid barrier (BCSFB). Overall, these data signify that T4 deiodinated by D2 may be the only source of T3 during neocortical development. We therefore propose that D2 activity at the BCSFB converts the T4 transported across the choroid plexus into T3, thus supplying the brain with active hormone to maintain TH homeostasis.


Assuntos
Córtex Cerebral , Embrião de Mamíferos/efeitos dos fármacos , Embrião de Mamíferos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Hormônios Tireóideos/metabolismo , Fatores Etários , Animais , Animais Recém-Nascidos , Peso Corporal/fisiologia , Córtex Cerebral/embriologia , Córtex Cerebral/crescimento & desenvolvimento , Córtex Cerebral/metabolismo , Feminino , Idade Gestacional , Iodeto Peroxidase/deficiência , Iodeto Peroxidase/genética , Isótopos de Iodo/metabolismo , Fígado/embriologia , Fígado/crescimento & desenvolvimento , Fígado/metabolismo , Proteínas de Membrana Transportadoras/deficiência , Proteínas de Membrana Transportadoras/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Transportadores de Ácidos Monocarboxílicos , Gravidez , RNA Mensageiro/metabolismo , Simportadores , Hormônios Tireóideos/farmacologia , Tirosina 3-Mono-Oxigenase/metabolismo , Iodotironina Desiodinase Tipo II
9.
Drug Metab Dispos ; 45(5): 468-475, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28228413

RESUMO

Predicting age-specific metabolism is important for evaluating age-related drug and chemical sensitivity. Multiple cytochrome P450s and carboxylesterase enzymes are responsible for human pyrethroid metabolism. Complete ontogeny data for each enzyme are needed to support in vitro to in vivo extrapolation (IVIVE). This study was designed to determine age-dependent human hepatic CYP2C8 expression, for which only limited ontogeny data are available, and to further define CYP1A2 ontogeny. CYP2C8 and 1A2 protein levels were measured by quantitative Western blotting using liver microsomal samples prepared from 222 subjects with ages ranging from 8 weeks gestation to 18 years after birth. The median CYP2C8 expression was significantly greater among samples from subjects older than 35 postnatal days (n = 122) compared with fetal samples and those from very young infants (fetal to 35 days postnatal, n = 100) (0.00 vs. 13.38 pmol/mg microsomal protein; p < 0.0001). In contrast, the median CYP1A2 expression was significantly greater after 15 months postnatal age (n = 55) than in fetal and younger postnatal samples (fetal to 15 months postnatal, n = 167) (0.0167 vs. 2.354 pmol/mg microsomal protein; p < 0.0001). CYP2C8, but not CYP1A2, protein levels significantly correlated with those of CYP2C9, CYP2C19, and CYP3A4 (p < 0.001), consistent with CYP2C8 and CYP1A2 ontogeny probably being controlled by different mechanisms. This study provides key data for the physiologically based pharmacokinetic model-based prediction of age-dependent pyrethroid metabolism, which will be used for IVIVE to support pyrethroid risk assessment for early life stages.


Assuntos
Envelhecimento/metabolismo , Citocromo P-450 CYP1A2/genética , Citocromo P-450 CYP2C8/genética , Expressão Gênica , Fígado/metabolismo , Microssomos Hepáticos/metabolismo , Adolescente , Adulto , Envelhecimento/genética , Criança , Pré-Escolar , Feminino , Desenvolvimento Fetal/genética , Ontologia Genética , Idade Gestacional , Humanos , Técnicas In Vitro , Lactente , Recém-Nascido , Fígado/embriologia , Fígado/enzimologia , Masculino , Microssomos Hepáticos/enzimologia , Medição de Risco , Xenobióticos/metabolismo , Adulto Jovem
10.
J Matern Fetal Neonatal Med ; 30(1): 74-78, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27011107

RESUMO

OBJECTIVES: Respiratory morbidity in congenital diaphragmatic hernia (CDH) is associated with high mortality and adverse outcome. Accurate prenatal diagnosis is essential for prognosis and potential treatment in utero. The aim was to evaluate the prenatal ultrasound findings in assessing the respiratory prognosis in fetuses with isolated left-sided CDH. METHODS: We retrospectively analyzed the medical records of 59 prenatally diagnosed left-sided CDH cases managed at a tertiary perinatal center. RESULTS: Survival rate in the study group was 73% (43/59). We found no statistically significant relationship between survival and the presence of polyhydramnios, gestational age at diagnosis, lung-to-head ratio (LHR) and observed/expected LHR (O/E LHR) values, gestational age at birth and birth weight. Intrathoracic liver herniation was a statistically significant parameter adversely affecting survival (37.2% in survivors, 68.8% in non-survivors, p = 0.031) and logistic regression confirmed this relationship. The presence of pneumothorax and severe pulmonary hypertension were significantly associated with mortality (82% non-survivors versus 15% in survivors, p = 0.0001). CONCLUSION: Intrathoracic liver herniation seems to be a reliable parameter in the prediction of survival and neonatal respiratory morbidity in fetuses with isolated left-sided CDH. In contrast, we found no significant correlation between perinatal outcome and LHR, O/E LHR values, birth weight and gestational age.


Assuntos
Cabeça/embriologia , Hérnias Diafragmáticas Congênitas/diagnóstico , Fígado/embriologia , Pulmão/embriologia , Ultrassonografia Pré-Natal , Feminino , Idade Gestacional , Cabeça/diagnóstico por imagem , Hérnias Diafragmáticas Congênitas/embriologia , Hérnias Diafragmáticas Congênitas/mortalidade , Humanos , Fígado/diagnóstico por imagem , Modelos Logísticos , Pulmão/diagnóstico por imagem , Gravidez , Prognóstico , Estudos Retrospectivos
11.
J Ultrasound Med ; 35(7): 1437-43, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27208195

RESUMO

OBJECTIVES: Liver herniation can be assessed sonographically by either a direct (liver-to-thoracic area ratio) or an indirect (stomach position) method. Our objective was to evaluate the utility of those methods to assess liver herniation for the prediction of neonatal outcomes in patients with isolated left-sided congenital diaphragmatic hernia (CDH). METHODS: We conducted a retrospective cohort study of all patients with CDH who had prenatal assessment and were delivered at Texas Children's Hospital between January 2004 and April 2014. The predictive value of sonographic parameters for mortality and the need for extracorporeal membrane oxygenation was evaluated by univariate, multivariate, and factor analysis and by receiver operating characteristics curves. RESULTS: A total of 77 fetuses with isolated left-sided CDH were analyzed. The lung-to-head ratio, liver-to-thorax ratio, and stomach position (according to the classifications of Kitano et al [Ultrasound Obstet Gynecol 2011; 37:277-282] and Cordier et al [J Matern Fetal Neonatal Med 2015; 28:190-195]) were significantly associated with both neonatal outcomes (P < .03). Significant correlations were observed between all of these sonographic parameters. A combination of the liver-to-thorax ratio and stomach position (Kitano) or stomach position (Cordier) with the lung-to-head ratio increased the area under the receiver operating characteristic curve of the lung-to-head ratio for mortality prediction (0.86 [95% confidence interval, 0.74-0.98], 0.83 [0.72-0.95], and 0.83 [0.74-0.92], respectively). CONCLUSIONS: Sonographic measurements of liver herniation (liver-to-thorax ratio and stomach position) are predictive of neonatal outcomes in isolated left-sided congenital diaphragmatic hernia. Our study shows that the combination of those sonographic measurements of liver herniation and lung size improves the accuracy of predicting mortality in those fetuses.


Assuntos
Doenças Fetais/diagnóstico por imagem , Hérnias Diafragmáticas Congênitas/diagnóstico por imagem , Hepatopatias/diagnóstico por imagem , Ultrassonografia Pré-Natal/métodos , Estudos de Coortes , Feminino , Humanos , Recém-Nascido , Fígado/diagnóstico por imagem , Fígado/embriologia , Gravidez , Reprodutibilidade dos Testes , Estudos Retrospectivos
12.
Magn Reson Med Sci ; 13(3): 167-73, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24990465

RESUMO

PURPOSE: We evaluated the feasibility of prenatal quantification of liver and spleen iron by magnetic resonance imaging (MRI) gradient recalled echo (GRE) measurements of transverse relaxation time (R2*) (MRI-GRE-R2*) in a fetal sheep model and applied the method to a human neonate with suspected neonatal hemochromatosis. METHODS: We subjected 13 fetal sheep to MRI at 1.5 Tesla using a breath-triggered (ewe) multi-echo sequence to determine the transverse relaxation rate (R2*) of the liver and spleen. In the human neonate, we measured the R2* of the liver, spleen, and pancreas on the 30th postgestational day. RESULTS: The median R2* of the fetal sheep liver was 25.6 s(-1) (range 20 to 114 s(-1)) and of the spleen, 40.2 s(-1) (range 20 to 70 s(-1)), and the corresponding median iron concentration in the liver was 0.85 mg/g dry weight (d.w.) and in the spleen, 1.22 mg/gd.w.. R2* rates in the human neonate liver were elevated between 67 s(-1) (average), which corresponded with an iron concentration of 1.9 mg Fe/gd.w., and 126 s(-1) (regional maximum), which corresponded with 3.4 mg Fe/gd.w.. The average pancreatic R2* (72.4 s(-1)) was significantly above normal values, which indicated iron overload. CONCLUSION: We demonstrated the feasibility of prenatal quantification of tissue iron by fetal MRI in this sheep model and successfully quantified iron, including that in the pancreas, in a human neonate to confirm the diagnosis of neonatal hemochromatosis. Transferring the successful approach of quantifying iron in intrauterine tissue in fetal sheep to human pregnancies with suspected fetal siderosis could aid early diagnosis.


Assuntos
Hemocromatose/diagnóstico , Ferro/metabolismo , Fígado/metabolismo , Imageamento por Ressonância Magnética/métodos , Pâncreas/metabolismo , Baço/metabolismo , Animais , Diagnóstico Diferencial , Estudos de Viabilidade , Feminino , Hemocromatose/metabolismo , Humanos , Sobrecarga de Ferro/diagnóstico , Sobrecarga de Ferro/metabolismo , Fígado/embriologia , Fígado/patologia , Pâncreas/patologia , Gravidez , Ovinos , Baço/embriologia , Baço/patologia
13.
AJR Am J Roentgenol ; 201(6): 1386-90, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24261381

RESUMO

OBJECTIVE: The purpose of this study was to retrospectively determine whether the ratio of fetal lung-to-liver signal intensities at single-shot fast spin-echo MRI is associated with fetal gestational age. MATERIALS AND METHODS: All fetal MRI examinations over a 4-year period were reviewed. All MRI examinations were performed with a 1.5-T magnet for indications other than lung maturity. Only examinations performed with a single-shot fast spin-echo sequence of the fetal chest and abdomen were included in the study. Images from a total of 82 fetal MRI examinations were evaluated. Gestational age ranged from 20 weeks to 39 weeks 3 days. Two board-certified subspecialty-trained radiologists with 11 and 17 years of experience blinded to estimated gestational age (EGA) reviewed the images independently. The regions of interest (ROIs) of the fetal lung and liver were drawn in the same plane and on the same image in each case. Fetal EGA was determined either by first-trimester ultrasound when available or by last menstrual period. Linear regression analysis was used to analyze the relation between the lung-to-liver signal-intensity ratio (LLSIR) in the ROIs and fetal EGA for both readers. The association between the LLSIRs estimated by the two readers was assessed by Bland-Altman plot. RESULTS: Summary statistics for LLSIR showed a median value of 2.29 for reader 1 and 2.21 for reader 2. The mean value for reader 1 was 2.4 and for reader 2 was 2.5. The Pearson correlation coefficients between the LLSIR and EGA variables were 0.44 for reader 1 and 0.45 for reader 2. Linear regression analysis showed a statistically significant association between LLSIR and EGA for both readers (p < 0.0004). This ratio increased in a linear manner as EGA progressed. CONCLUSION: Fetal LLSIR at single-shot fast spin-echo MRI is associated with fetal gestational age.


Assuntos
Maturidade dos Órgãos Fetais , Fígado/embriologia , Pulmão/embriologia , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Feminino , Idade Gestacional , Humanos , Gravidez , Estudos Retrospectivos
14.
Exp Toxicol Pathol ; 65(6): 729-35, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23121990

RESUMO

In three independent laboratories carcinogens (diethylnitrosamine, DEN, 4-(N-methyl-N-nitrosamino)-1-(3-pyridyl)-1-butanone, NNK) and non-carcinogens (N-nitrosoproline, nicotine) were evaluated in turkey eggs for in ovo carcinogenicity assessment (IOCA). Compounds were injected into aseptic fertilized eggs. After incubation for 24 days, foci of altered hepatocytes (FAH), some with a pseudoglandular structure and/or signs of compression of the surrounding tissue were observed in the fetal liver. All laboratories were able to distinguish unequivocally the hepatocarcinogen-exposed groups from those exposed to non-carcinogens or the vehicle controls, based on the pre-specified evaluation parameters: tumor-like lesions, pseudoglandular areas and FAH. In addition to focal changes, only the carcinogens induced hepatocellular karyomegaly. Lower doses of the carcinogens, which did not induce FAH, were sufficient to induce hepatocellular karyomegaly. After exposure to 4 mg DEN, gall bladder agenesis was observed in all fetuses. The IOCA may be a valuable tool for early investigative studies on carcinogenicity and since it does not use rodents may complement chronic rat or mouse bioassays. Test substances that are positive in both rodents and fertilized turkey eggs are most probably trans-species carcinogens with particular significance for humans. The good concordance observed among the three laboratories demonstrates that the IOCA is a reliable and robust method.


Assuntos
Hepatócitos/efeitos dos fármacos , Laboratórios/normas , Neoplasias Hepáticas Experimentais/induzido quimicamente , Fígado/efeitos dos fármacos , Perus , Animais , Testes de Carcinogenicidade/métodos , Testes de Carcinogenicidade/normas , Relação Dose-Resposta a Droga , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/patologia , Hepatócitos/patologia , Fígado/embriologia , Fígado/patologia , Neoplasias Hepáticas Experimentais/embriologia , Neoplasias Hepáticas Experimentais/patologia , Reprodutibilidade dos Testes , Projetos de Pesquisa , Zigoto/efeitos dos fármacos , Zigoto/patologia
15.
J Cell Biochem ; 113(1): 19-30, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21956183

RESUMO

The in vitro derived hepatocytes from human embryonic stem cells (hESC) is a promising tool to acquire improved knowledge of the cellular and molecular events underlying early human liver development under physiological and pathological conditions. Here we report a simple two-step protocol employing conditioned medium (CM) from human hepatocellular carcinoma cell line, HepG2 to generate functional hepatocyte-like cells from hESC. Immunocytochemistry, flow cytometry, quantitative RT-PCR, and biochemical analyses revealed that the endodermal progenitors appeared as pockets in culture, and the cascade of genes associated with the formation of definitive endoderm (HNF-3ß, SOX-17, DLX-5, CXCR4) was consistent and in concurrence with the up-regulation of the markers for hepatic progenitors [alpha-feto protein (AFP), HNF-4α, CK-19, albumin, alpha-1-antitrypsin (AAT)], followed by maturation into functional hepatocytes [tyrosine transferase (TAT), tryptophan-2, 3-dioxygenase (TDO), glucose 6-phosphate (G6P), CYP3A4, CYP7A1]. We witnessed that the gene expression profile during this differentiation process recapitulated in vivo liver development demonstrating a gradual down-regulation of extra embryonic endodermal markers (SOX-7, HNF-1ß, SNAIL-1, LAMININ-1, CDX2), and the generated hepatic cells performed multiple liver functions. Since prenatal alcohol exposure is known to provoke irreversible abnormalities in the fetal cells and developing tissues, we exposed in vitro generated hepatocytes to ethanol (EtOH) and found that EtOH treatment not only impairs the survival and proliferation, but also induces apoptosis and perturbs differentiation of progenitor cells into hepatocytes. This disruption was accompanied by alterations in the expression of genes and proteins involved in hepatogenesis. Our results provide new insights into the wider range of destruction caused by alcohol on the dynamic process of liver organogenesis.


Assuntos
Diferenciação Celular/fisiologia , Células-Tronco Embrionárias/citologia , Hepatócitos/citologia , Hepatócitos/fisiologia , Biomarcadores , Linhagem Celular , Sobrevivência Celular , Meios de Cultivo Condicionados/farmacologia , Etanol/metabolismo , Perfilação da Expressão Gênica , Células Hep G2 , Hepatócitos/metabolismo , Humanos , Fígado/embriologia , Fígado/metabolismo , Hepatopatias Alcoólicas/patologia , Organogênese/fisiologia
16.
Histochem Cell Biol ; 136(5): 595-607, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21932072

RESUMO

The paired box transcription factor Pax8 is critical for development of the eye, thyroid gland as well as the urinary and reproductive organs. In adult, Pax8 overexpression is associated with kidney, ovarian and thyroid tumors and has emerged as a specific marker for these cancers. Recently, Pax8 expression was also reported in human pancreatic islets and in neuroendocrine tumors, identifying Pax8 as a novel member of the Pax family expressed in the pancreas. Herein, we sought to provide a comprehensive analysis of Pax8 expression during pancreogenesis and in adult islets. Immunohistochemical analysis using the most employed Pax8 polyclonal antibody revealed strong nuclear staining in the developing mouse pancreas and in mature human and mouse islets. Astonishingly, Pax8 mRNA in mouse islets was undetectable while human islets exhibited low levels. These discrepancies raised the possibility of antibody cross-reactivity. This premise was confirmed by demonstrating that the polyclonal Pax8 antibody also recognized the islet-enriched Pax6 protein both by Western blotting and immunohistochemistry. Thus, in islets polyclonal Pax8 staining corresponds mainly to Pax6. In order to circumvent this caveat, a novel Pax8 monoclonal antibody was used to re-evaluate whether Pax8 was indeed expressed in islets. Surprisingly, Pax8 was not detected in neither the developing pancreas or in mature islets. Reappraisal of pancreatic neuroendocrine tumors using this Pax8 monoclonal antibody exhibited no immunostaining as compared to the Pax8 polyclonal antibody. In conclusion, Pax8 is not expressed in the pancreas and cast doubts on the value of Pax8 as a pancreatic neuroendocrine tumor marker.


Assuntos
Ilhotas Pancreáticas/embriologia , Tumores Neuroendócrinos/metabolismo , Fatores de Transcrição Box Pareados/metabolismo , Neoplasias Pancreáticas/metabolismo , Animais , Animais Recém-Nascidos , Biomarcadores Tumorais/metabolismo , Núcleo Celular/metabolismo , Reações Cruzadas , Embrião de Mamíferos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Ilhotas Pancreáticas/metabolismo , Rim/embriologia , Rim/metabolismo , Fígado/embriologia , Fígado/metabolismo , Camundongos , Tumores Neuroendócrinos/patologia , Fator de Transcrição PAX8 , Fatores de Transcrição Box Pareados/genética , Pâncreas/embriologia , Pâncreas/metabolismo , Neoplasias Pancreáticas/patologia , RNA Mensageiro/metabolismo
17.
Best Pract Res Clin Obstet Gynaecol ; 23(6): 751-64, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19854107

RESUMO

Intrauterine growth restriction (IUGR) is a major cause of foetal and neonatal morbidity and mortality. During post mortem, the pathologist is well placed to diagnose the presence and cause of IUGR in a stillborn baby. This article describes the approach of the pathologist in diagnosing IUGR and some of the pitfalls. We distinguish between reduced growth potential (formerly symmetrical IUGR) and nutritional IUGR (formerly asymmetrical IUGR). Aetiologically, restricted growth can be of foetal, maternal and placental origin. We discuss the importance of identifying the cause of IUGR in a clinicopathological context and the pathological findings in some of the more frequent causes of IUGR presenting at post mortem. Based on an accurate gestational age, ideally determined by the obstetrician in early pregnancy, the pathologist can derive a birth weight centile. However, the pathologist is also able to identify other indicators of IUGR, such as an elevated brain/liver weight ratio, atrophic thymus and changes in other internal organs. Placental examination plays a major role in the investigation as the majority of IUGR cases have significant placental pathology. This includes pre-eclampsia-related changes, abnormalities of the villous parenchyma and pathology of the umbilical cord. The potential benefit of a meticulous workup of IUGR foetuses is to provide an explanation of the pathological condition and to identify avoidable causes.


Assuntos
Desenvolvimento Fetal/fisiologia , Retardo do Crescimento Fetal/patologia , Encéfalo/embriologia , Aberrações Cromossômicas/embriologia , Doença Crônica , Feminino , Morte Fetal/patologia , Retardo do Crescimento Fetal/fisiopatologia , Idade Gestacional , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Infecções/embriologia , Fígado/embriologia , Doenças Placentárias/patologia , Circulação Placentária/fisiologia , Gravidez
18.
Surg Radiol Anat ; 31(7): 517-21, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19214364

RESUMO

Bile ducts of Luschka (also called subvesical or supravesicular ducts) can cause bile leakage during laparoscopic cholecystectomy, especially if surgery is carried out in ignorance of such variations. The aim of this study was to clarify the clinical anatomy of these ducts in human fetuses and frequency of the ducts locating near gallbladder fossa. Thirty-two fetal cadaver livers were dissected and the gallbladders were separated from the livers and ducts were investigated under a surgical microscope. All observed ducts were examined microscopically and connective tissue cords were excluded. Bile ducts of Luschka locating near cystic fossa were found in 7 of 32 fetuses (21.9%). Three of the seven ducts ran towards to liver segment 5 (S5); three ducts were found in the gallbladder fossa; and one duct ran towards to liver segment 4 (S4). Also it was found that three of the seven ducts drained into the subsegmental duct of S5, two ducts drained into the right hepatic duct, one duct drained into the right anterior branch bile duct, and one duct drained into the subsegmental duct of S4. Subvesical ducts running along the gallbladder fossa between the gallbladder and the liver parenchyma were found in a relatively high incidence in fetuses than adults. Awareness and knowledge about incidence of such ducts alerts the surgeon during laparoscopic cholecystectomy. Therefore morbidity due to bile leaks can be reduced.


Assuntos
Ductos Biliares/anatomia & histologia , Feto/anatomia & histologia , Ductos Biliares/embriologia , Vesícula Biliar/anatomia & histologia , Vesícula Biliar/embriologia , Humanos , Fígado/anatomia & histologia , Fígado/embriologia
19.
Ultrasound Obstet Gynecol ; 31(5): 529-34, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18432599

RESUMO

OBJECTIVES: Assessing fetal liver size might be useful in monitoring the effectiveness of the treatment of diabetes in pregnancy. We aimed to assess the reproducibility of fetal liver-length measurement in pregnant women with diabetes. METHODS: From 3 April 2006 to 5 December 2006, we assessed intraobserver and interobserver variation of fetal liver-length measurements on 55 sonograms in 44 pregnant women with diabetes, 34 of whom had gestational diabetes. The mean maternal age was 33 years, the mean maternal weight was 92 kg and the mean body mass index (BMI) was 33.7 kg/m(-2). The effect of covariates BMI, gestational age and maternal age on the reproducibility of fetal liver length was assessed by calculating intraobserver SD ratios. We compared liver length with abdominal circumference and gestational age. Nine of 12 sonographers scanned, on average, six women (range, 3-12) as the first sonographer, and all 12 sonographers scanned, on average, four women (range, 1-10) as the second sonographer. The data were analyzed using a hierarchical linear model. RESULTS: Measurement of fetal liver length was reproducible. The intraobserver SD was 3.06 (95% CI, 2.68-3.59) mm; the interobserver SD was 2.17 (95% CI, 0.59-4.83) mm; the intraobserver correlation was 0.77 (95% CI, 0.63-0.87), and the interobserver correlation was 0.84 (95% CI, 0.51-0.99). The covariate effects were minimal, the SD for a 1-unit increase in the covariate was 1.06 for gestational age, 0.98 for BMI, and 0.97 for maternal age. CONCLUSIONS: Measurement of fetal liver length in the diabetic pregnancy is reproducible. It is worthy of further investigation as a parameter for monitoring the effectiveness of treatment of the diabetic pregnancy.


Assuntos
Diabetes Mellitus/fisiopatologia , Desenvolvimento Fetal/fisiologia , Fígado/embriologia , Gravidez em Diabéticas/fisiopatologia , Ultrassonografia Pré-Natal/métodos , Adulto , Feminino , Idade Gestacional , Humanos , Fígado/diagnóstico por imagem , Variações Dependentes do Observador , Gravidez , Reprodutibilidade dos Testes
20.
Prenat Diagn ; 24(9): 671-6, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15386455

RESUMO

OBJECTIVES: This study was performed to evaluate the quantitative ultrasonic tissue characterization of the normal fetal lung development by using acoustic raw data captured after preprocessing. METHODS: One hundred and sixty-two patients with completed gestational ages between 22 and 37 weeks were enrolled in this study. Longitudinal and transverse sections of the fetal thorax and upper abdomen were imaged. A region of interest of constant size was defined and the tissue-specific gray scale was determined by using an interactive software. RESULTS: A total of 162 patients met the inclusion criteria. The echogenicity of the fetal lung showed a particular changing pattern during pregnancy: the mean gray value of the fetal lung (MGV) is almost the same as the MGV of the fetal liver at 22 and 23 weeks, decreases between 22 and 31 weeks and increases between 31 and 37 weeks. The MGV of the fetal liver decreases significantly from 24 weeks to 31 weeks and increases significantly again toward 37 weeks. We stated that the MGV of the lung is smaller than the MGV of the liver during 31 weeks of gestation and the relation reverses in late gestation. At term, the MGV of the liver is greater than the MGV of the lung. The lung-to-liver ratio is <1 between 24 and 29 weeks and >1 between 30 and 35 weeks. CONCLUSION: The echogenicity of the fetal lung showed a particular changing pattern during pregnancy, which corresponds to morphologic changes of the fetal lung development.


Assuntos
Maturidade dos Órgãos Fetais , Pulmão/diagnóstico por imagem , Pulmão/embriologia , Ultrassonografia Pré-Natal , Feminino , Idade Gestacional , Humanos , Processamento de Imagem Assistida por Computador , Fígado/diagnóstico por imagem , Fígado/embriologia , Gravidez
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