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1.
Ginecol Obstet Mex ; 72: 335-44, 2004 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-15469172

RESUMO

BACKGROUND: The intraovarian oxidative balance is important during oocyte development, and fertilization. It has been proposed that one of the most important enzymes in the follicle is the superoxide dismutase (SOD). OBJECTIVE: To correlate levels and percentage of SOD activity in follicular liquid with quality, fertilization and embryo development in a group of patients submitted to in vitro fertilization. MATERIAL AND METHODS: We obtained 120 follicular liquids from oocytes aspirated in 41 patients during an IVF program and then we followed the development of each oocyte separately. We measured the activity and concentration of SOD in the follicular liquid, and we evaluated the following variables: quality and maturity in the oocytes, as well as fertilization rate, segmentation rate and pregnancy. The statistical analysis was made with ANOVA test and Pearson test. RESULTS: In the analysis of the results, we observed a higher percentage of activity in the SOD in oocytes with good quality (3 and 4) in comparison with poor quality oocyte (1 and 2) (89 and 82% vs 75 and 61% p<0.05). We observed higher concentrations and activity of SOD in oocytes with a good fertilization rate and segmentation (p<0.05). When we analyzed the variables in function of pregnancy, we observed that the embryos that were transferred and developed pregnancy had higher concentrations and activity of SOD than embryos that did not develop pregnancy. CONCLUSIONS: Elevated levels and high percentage in the activity of SOD are associated with a better quality in the oocyte, and a good embryo development, influenced by the oxidative balance.


Assuntos
Desenvolvimento Embrionário e Fetal , Fertilização In Vitro , Oócitos/fisiologia , Folículo Ovariano/enzimologia , Superóxido Dismutase/metabolismo , Feminino , Humanos
2.
Am J Obstet Gynecol ; 191(3): 700-7, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15467528

RESUMO

OBJECTIVE: Information on outcome by gestational age from large numbers of twins and triplets is limited and is important for counseling and decision-making in obstetric practice. We reviewed one of the largest available neonatal databases to describe mortality and morbidity rates and growth in newborn infants from multiple gestations and compared these data with data for singletons. STUDY DESIGN: Data from a large prospectively recorded neonatal database that incorporated neonatal records from January 1997 to July 2002 were reviewed. We evaluated birth weight and neonatal mortality and morbidity rates that affected long-term outcome for each week of gestational age from 23 to 35 weeks of gestation for all nonanomolous inborn twins and triplets who were admitted to the neonatal intensive care unit and compared these data to all singletons who met similar criteria during the same time period. RESULTS: There were 12,302 twin and 2155 triplet births that met the entry criteria. The data for these newborn infants were compared with 36,931 singletons. Average birth weights at each gestational week were similar for all gestational ages until 29 weeks of gestation for triplets and 32 weeks of gestation for twins. After these gestational ages, the entire difference between twins and singletons was due to the weight of the smaller twin; the larger twins' mean weights were similar to singletons at all weeks that were studied. Birth order at each week also did not affect neonatal mortality rates, even when corrected for route of delivery and antenatal steroids. Neonatal morbidities associated with adverse long-term outcomes (intraventricular hemorrhage, retinopathy of prematurity, necrotizing enterocolitis) were also not different between multiple infants and singletons. Intrauterine growth restriction (IUGR) was associated with increased mortality rates at all gestational ages, but in the absences of IUGR, discordance was not. CONCLUSION: Data on a large number of twins and triplets provide reassurance that neonatal outcome at all viable premature weeks of gestation are similar to singletons. Intrauterine growth restriction and prematurity are therefore the principal issues that drive neonatal mortality and morbidity rates in multiple gestations. These data are important for obstetric decision-making and patient counseling.


Assuntos
Desenvolvimento Embrionário e Fetal , Idade Gestacional , Resultado da Gravidez , Trigêmeos , Gêmeos , Peso ao Nascer , Feminino , Retardo do Crescimento Fetal/mortalidade , Humanos , Mortalidade Infantil , Recém-Nascido , Recém-Nascido Prematuro , Terapia Intensiva Neonatal , Morbidade , Gravidez , Gravidez Múltipla
3.
J Heart Valve Dis ; 13(5): 841-7, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15473488

RESUMO

BACKGROUND AND AIM OF THE STUDY: The roles of cardiac valvular interstitial cells (VIC) in extracellular matrix remodeling in fetal development, adaptation and response to injury are largely unknown. METHODS: The phenotype of VIC was studied in health (normal adult human and sheep), development (fetal human and sheep), disease (human mitral valves with myxomatous degeneration), adaptation (clinical pulmonary to aortic valve autografts) and tissue-engineered heart valves matured in vitro and remodeled in vivo. Cell phenotype was assessed using expression of vimentin (V), alpha-smooth muscle actin (SMA, A), matrix metalloproteinase (MMP)-13/collagenase-3 (M), and SMemb (S). RESULTS: VIC in normal adult valves were predominantly quiescent fibroblasts immunoreactive to vimentin (89.7 +/- 2.5%), but not MMP-13 or SMemb, with only 2.5 +/- 0.4% of alpha-SMA-positive cells ('normal/quiescent' phenotype: V+/A-/M-/S-). In contrast, fetal VIC were mostly activated myofibroblasts ('developing/activated' phenotype: V+/A+/M+/S+), with 62.1 +/- 5.0% of cells staining positive for alpha-SMA. VIC in myxomatous valves, short-term autografts and engineered valves in vitro were also activated myofibroblasts with coexpression of vimentin, alpha-SMA (36.2 +/- 3.7%, 19.3 +/- 2.4%, and 60.3 +/- 9% positive cells, respectively), strong MMP-13 activity indicative of collagen remodeling, and SMemb ('remodeling/activated' phenotype: V+/A+/M+/S+). In contrast, VIC in long-term pulmonary autografts and engineered valve explants had a mostly fibroblast-like phenotype, with sparse alpha-SMA expression (6.0 +/- 1% and 5.4 +/- 1.0% positive cells) (V+/A-/M-/S-). CONCLUSION: Most VIC in normal valves were quiescent with a fibroblast-like phenotype. VIC in developing, diseased, adapting and engineered valves adjust to a dynamic environment through VIC activation and secretion of proteolytic enzymes mediating extracellular matrix remodeling ('developing/ remodeling/activated' phenotype), followed by a normalization of phenotype.


Assuntos
Fibroblastos/fisiologia , Doenças das Valvas Cardíacas/fisiopatologia , Valvas Cardíacas/fisiologia , Actinas/biossíntese , Adulto , Animais , Colagenases/biossíntese , Desenvolvimento Embrionário e Fetal/fisiologia , Próteses Valvulares Cardíacas , Valvas Cardíacas/citologia , Valvas Cardíacas/embriologia , Valvas Cardíacas/fisiopatologia , Humanos , Metaloproteinase 13 da Matriz , Músculo Liso/metabolismo , Miosinas/biossíntese , Fenótipo , Ovinos , Engenharia Tecidual , Vimentina/biossíntese
4.
Am J Epidemiol ; 160(8): 774-83, 2004 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-15466500

RESUMO

Previous studies, mainly among populations with high consumption of seafood, have suggested that increased marine n-3 polyunsaturated fatty acid (PUFA) intake during pregnancy promotes longer gestation and higher birth weight. Few studies have isolated the contribution of fetal growth to birth weight. Using data from 2,109 pregnant women in Massachusetts enrolled in Project Viva from 1999 to 2002, the authors examined associations of marine n-3 PUFA and seafood intake with birth weight and birth-weight-for-gestational-age z value (fetal growth) using linear regression; length of gestation using median regression; and low birth weight, preterm delivery, and being small for gestational age using logistic regression. After adjustment for maternal and child factors, birth weight was 94 (95% confidence interval: 23, 166) g lower and fetal growth z value 0.19 (95% confidence interval: 0.08, 0.31) units lower in the highest compared with the lowest quartile of first-trimester n-3 PUFA intake. Results for the second and third trimesters were similar, and findings for seafood paralleled those for n-3 PUFA. Elongated n-3 PUFA intake and seafood intake were not associated with length of gestation or risk of preterm birth. Results from this US cohort support the conclusion that seafood intake during pregnancy is associated with reduced fetal growth.


Assuntos
Peso ao Nascer , Desenvolvimento Embrionário e Fetal , Ácidos Graxos Ômega-3/administração & dosagem , Idade Gestacional , Alimentos Marinhos , Inquéritos sobre Dietas , Ingestão de Energia , Feminino , Retardo do Crescimento Fetal/epidemiologia , Retardo do Crescimento Fetal/etiologia , Retardo do Crescimento Fetal/prevenção & controle , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Modelos Lineares , Modelos Logísticos , Masculino , Massachusetts/epidemiologia , Análise Multivariada , Obesidade/complicações , Obesidade/epidemiologia , Trabalho de Parto Prematuro/epidemiologia , Trabalho de Parto Prematuro/etiologia , Trabalho de Parto Prematuro/prevenção & controle , Gravidez , Complicações na Gravidez/epidemiologia , Resultado da Gravidez/epidemiologia , Estudos Prospectivos , Fatores de Risco , Fumar/efeitos adversos , Fumar/epidemiologia , Inquéritos e Questionários
5.
Jpn J Vet Res ; 52(2): 77-84, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15481861

RESUMO

Effects of oxygen (O2) tension in the gas atmosphere during in vitro maturation (IVM), in vitro fertilization (IVF) and in vitro culture (IVC) on the efficiency of in vitro production of mouse embryos were examined. Mouse oocytes recovered from large antral follicles were subjected to IVM in Waymouth medium for 15, 16 and 17 hr under 5 or 20% O2 and then subjected to IVF and IVC under 5 or 20% O2 tension. Lowering the O2 tension in the gas atmosphere for IVM from 20 to 5% improved the cleavage rate after IVF when the oocytes were subjected to IVM for 15 hr; however, no improvement in the cleavage rate was observed when the culture period for IVM was extended to 16 and 17 hr. Lowering the O2 tension to 5% for IVM and IVC improved the development of the cleaved oocytes to the blastocyst stage, regardless of the culture period for IVM. However, the O2 tension for IVF had no remarkable effect on the subsequent embryonic development. These results demonstrate that 5% O2 is superior to 20% O2 for IVM and IVC, and suggest that 20% O2 for IVM may delay oocyte maturation and/or the acquisition of fertilizability and impair the developmental competence of oocytes.


Assuntos
Embrião de Mamíferos/efeitos dos fármacos , Embrião de Mamíferos/fisiologia , Camundongos/embriologia , Oócitos/efeitos dos fármacos , Oxigênio/farmacologia , Animais , Técnicas de Cultura de Células/métodos , Divisão Celular/efeitos dos fármacos , Divisão Celular/fisiologia , Relação Dose-Resposta a Droga , Desenvolvimento Embrionário e Fetal/efeitos dos fármacos , Desenvolvimento Embrionário e Fetal/fisiologia , Feminino , Fertilização In Vitro/veterinária , Masculino , Camundongos Endogâmicos ICR , Oócitos/metabolismo , Oócitos/fisiologia , Oxigênio/metabolismo , Distribuição Aleatória , Fatores de Tempo
6.
Yi Chuan Xue Bao ; 31(6): 641-6, 2004 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-15490885

RESUMO

Although the cloned animals have been successfully generated in a number of mammalian species, there are still many problems about this technology. The developmental aberrancies include a high rate of abortion during early gestation and high rate of perinatal death. The main cause of these problems may be attributed to the epigenetic reprogramming of somatic donor genome. During mammalian embryonic development, DNA methylation is an essential process in the regulation of transcription. There are many aberrant methylation in various genomic regions of cloned embryos. The gene imprinting of cloned embryos are also abnormal.


Assuntos
Clonagem de Organismos , Metilação de DNA , Impressão Genômica , Técnicas de Transferência Nuclear , Desenvolvimento Embrionário e Fetal , Regulação da Expressão Gênica no Desenvolvimento
7.
Mol Cell Biol ; 24(18): 8090-103, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15340071

RESUMO

Hox genes are differentially expressed along the embryonic anteroposterior axis. We used chromatin immunoprecipitation to detect chromatin changes at the Hoxd4 locus during neurogenesis in P19 cells and embryonic day 8.0 (E8.0) and E10.5 mouse embryos. During Hoxd4 induction in both systems, we observed that histone modifications typical of transcriptionally active chromatin occurred first at the 3' neural enhancer and then at the promoter. Moreover, the sequential distribution of histone modifications between E8.0 and E10.5 was consistent with a spreading of open chromatin, starting with the enhancer, followed by successively more 5' intervening sequences, and culminating at the promoter. Neither RNA polymerase II (Pol II) nor CBP associated with the inactive gene. During Hoxd4 induction, CBP and RNA Pol II were recruited first to the enhancer and then to the promoter. Whereas the CBP association was transient, RNA Pol II remained associated with both regulatory regions. Histone modification and transcription factor recruitment occurred in posterior, Hox-expressing embryonic tissues, but never in anterior tissues, where such genes are inactive. Together, our observations demonstrate that the direction of histone modifications at Hoxd4 mirrors colinear gene activation across Hox clusters and that the establishment of anterior and posterior compartments is accompanied by the imposition of distinct chromatin states.


Assuntos
Padronização Corporal/genética , Histonas/metabolismo , Fatores de Transcrição/genética , Animais , Sequência de Bases , Diferenciação Celular , Linhagem Celular , Cromatina/genética , Cromatina/metabolismo , DNA/genética , Desenvolvimento Embrionário e Fetal/genética , Elementos Facilitadores Genéticos , Regulação da Expressão Gênica no Desenvolvimento , Camundongos , Regiões Promotoras Genéticas , Rombencéfalo/embriologia , Rombencéfalo/metabolismo , Ativação Transcricional/efeitos dos fármacos , Transfecção , Tretinoína/farmacologia
8.
Nat Genet ; 36(9): 935-6, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15340429

RESUMO

Several mutant strains of mice have dark skin pigmentation due to an aberrant accumulation of pigment-producing melanocytes in the dermal layer of the skin. A new study shows that three such strains carry activating mutations in the genes encoding the G-protein subunits Galphaq or Galpha11, resulting in more pigment cell precursors and an excess of dermally retained pigment cells at birth.


Assuntos
Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/genética , Pigmentação da Pele/genética , Animais , Desenvolvimento Embrionário e Fetal/genética , Melanócitos/fisiologia , Camundongos , Camundongos Mutantes/embriologia , Mutação de Sentido Incorreto , Receptores de Superfície Celular/genética
9.
Med Humanit ; 30(1): 12-22, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15341042

RESUMO

The nineteenth century science of teratology concerned itself with the study of malformations or "monstrosities", as they were then called. The first major contribution to the field was the work of Isidore Geoffrey Saint-Hilaire, Historie Generale et Particuliere des Anomalies de l'Organisation chez l'Homme et les Animaux, published in 1832, whose classifications formed the basis for the later experimental science of teratogeny, the art of reproducing monstrosities in animal embryos. In this article, I will argue that recent developments in the field of regenerative medicine can be situated in the tradition of teratological and teratogenic studies dating back to the nineteenth century. In particular, I will be interested in the historical link between studies in teratogenesis (the artificial production of teratomas) and stem cell research. Recent advances in stem cell research, I will suggest, return us to the questions that animated nineteenth century investigations into the nature of the monstrous or the anomalous. In the process, our most intuitive conceptions of "life itself" are undergoing a profound transformation.


Assuntos
Anormalidades Congênitas/história , Embrião de Mamíferos/citologia , História do Século XIX , Vida , Filosofia/história , Células-Tronco , Teratologia/história , Animais , Evolução Biológica , Desenvolvimento Embrionário e Fetal/fisiologia , História do Século XX , Humanos , Células-Tronco/citologia , Teratoma/classificação
10.
Biochem Biophys Res Commun ; 322(3): 887-92, 2004 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-15336546

RESUMO

Fgf18 is abundantly expressed in mouse embryonic lungs. To elucidate the roles of Fgf18 in mouse embryonic lung development, we examined the Fgf18-/- embryonic lungs. Although the sizes of the Fgf18-/- lungs were a little smaller in appearance than those of wild-type lungs, neither proximal nor distal airway branching in the Fgf18-/- lungs was impaired. However, the Fgf18-/- lungs at E18.5 had reduced alveolar space, thicker interstitial mesenchymal compartments, and many embedded capillaries. Cell proliferation in the Fgf18-/- lungs was also transiently reduced around E17.5, although the expression of marker genes for lung epithelial cells in the Fgf18-/- lungs was not impaired. The present findings indicate that the Fgf18 plays roles in lung alveolar development during late embryonic lung development stages. The cell proliferation during the terminal saccular stage stimulated by Fgf18 might play roles in the remodeling of the distal lung.


Assuntos
Fatores de Crescimento de Fibroblastos/fisiologia , Alvéolos Pulmonares/embriologia , Animais , Divisão Celular/genética , Divisão Celular/fisiologia , Desenvolvimento Embrionário e Fetal/genética , Desenvolvimento Embrionário e Fetal/fisiologia , Fatores de Crescimento de Fibroblastos/deficiência , Fatores de Crescimento de Fibroblastos/genética , Pulmão/citologia , Pulmão/embriologia , Camundongos , Camundongos Knockout , Alvéolos Pulmonares/citologia
11.
Philos Trans R Soc Lond B Biol Sci ; 359(1449): 1359-66, 2004 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-15347527

RESUMO

Low birthweight is now known to be associated with increased rates of coronary heart disease and the related disorders, stroke, hypertension and adult-onset diabetes. These associations have been extensively replicated in studies in different countries and are not the result of confounding variables. They extend across the normal range of birthweight and depend on lower birthweights in relation to the duration of gestation rather than the effects of premature birth. The associations are thought to be consequences of developmental plasticity, the phenomenon by which one genotype can give rise to a range of different physiological or morphological states in response to different environmental conditions during development. Recent observations have shown that impaired growth in infancy and rapid childhood weight gain exacerbate the effects of impaired prenatal growth. A new vision of optimal early human development is emerging, which takes account of health and well-being throughout life.


Assuntos
Desenvolvimento Infantil/fisiologia , Desenvolvimento Embrionário e Fetal/fisiologia , Retardo do Crescimento Fetal/complicações , Nível de Saúde , Recém-Nascido de Baixo Peso/fisiologia , Composição Corporal , Estatura , Índice de Massa Corporal , Doença das Coronárias/etiologia , Diabetes Mellitus Tipo 2/etiologia , Humanos , Recém-Nascido , Fatores de Risco
12.
Proc Nutr Soc ; 63(3): 397-403, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15373949

RESUMO

It is apparent from epidemiological studies that the timing of maternal nutrient restriction has a major influence on outcome in terms of predisposing the resulting offspring to adult obesity. The present review will consider the extent to which maternal age, parity and nutritional restriction at defined stages of gestation can have important effects on fat deposition and endocrine sensitivity of adipose tissue in the offspring. For example, in 1-year-old sheep the offspring of juvenile mothers have substantially reduced fat deposition compared with those born to adult mothers. Offspring of primiparous adult mothers, however, show increased adiposity compared with those born to multiparous mothers. These offspring of multiparous ewes show retained abundance of the brown adipose tissue-specific uncoupling protein 1 at 1 month of age. A stimulated rate of metabolism in brown fat of these offspring may act to reduce adipose tissue deposition in later life. In terms of defined windows of development that can programme adipose tissue growth, maternal nutrient restriction targetted over the period of maximal placental growth results in increased adiposity at term in conjunction with enhanced abundance of mRNA for the insulin-like growth factor-I and -II receptors. In contrast, nutrient restriction in late gestation, coincident with the period of maximal fetal growth, has no major effect on adiposity but results in greater abundance of specific mitochondrial proteins, i.e. voltage-dependent anion channel and/or uncoupling protein 2. These adaptations may increase the predisposal of these offspring to adult obesity. Increasing maternal nutrition in late gestation, however, can result in proportionately less fetal adipose tissue deposition in conjunction with enhanced abundance of uncoupling protein 1.


Assuntos
Tecido Adiposo/embriologia , Tecido Adiposo/crescimento & desenvolvimento , Sistema Endócrino/fisiologia , Fenômenos Fisiológicos da Nutrição Materna/fisiologia , Obesidade/epidemiologia , Fenômenos Fisiológicos da Nutrição Pré-Natal/fisiologia , Adulto , Animais , Dieta Redutora/efeitos adversos , Desenvolvimento Embrionário e Fetal , Feminino , Humanos , Idade Materna , Obesidade/etiologia , Paridade , Gravidez , Efeitos Tardios da Exposição Pré-Natal
13.
Proc Nutr Soc ; 63(3): 405-12, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15373950

RESUMO

Exposure to either an increased or decreased level of intrauterine nutrition can result in an increase in adiposity and in circulating leptin concentrations in later life. In animals such as the sheep and pig in which fat is deposited before birth, leptin is synthesised in fetal adipose tissue and is present in the fetal circulation throughout late gestation. In the sheep a moderate increase or decrease in the level of maternal nutrition does not alter fetal plasma leptin concentrations, but there is evidence that chronic fetal hyperglycaemia and hyperinsulinaemia increase fetal fat mass and leptin synthesis within fetal fat depots. Importantly, there is a positive relationship between the relative mass of the 'unilocular' component of fetal perirenal and interscapular adipose tissue and circulating fetal leptin concentrations in the sheep. Thus, as in the neonate and adult, circulating leptin concentrations may be a signal of fat mass in fetal life. There is also evidence that leptin can act to regulate the lipid storage, leptin synthetic capacity and potential thermogenic functions of fat before birth. Thus, leptin may act as a signal of energy supply and have a 'lipostatic' role before birth. Future studies are clearly required to determine whether the intrauterine and early postnatal nutrient environment programme the endocrine feedback loop between adipose tissue and the central and peripheral neuroendocrine systems that regulate energy balance, resulting in an enhanced risk of obesity in adult life.


Assuntos
Tecido Adiposo/metabolismo , Peso ao Nascer/fisiologia , Desenvolvimento Embrionário e Fetal/fisiologia , Feto/metabolismo , Leptina/biossíntese , Fenômenos Fisiológicos da Nutrição Pré-Natal/fisiologia , Animais , Metabolismo Energético , Feminino , Humanos , Recém-Nascido , Leptina/metabolismo , Masculino , Fenômenos Fisiológicos da Nutrição Materna , Estado Nutricional , Obesidade/epidemiologia , Obesidade/etiologia , Gravidez , Ovinos , Suínos
14.
Proc Nutr Soc ; 63(3): 481-90, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15373961

RESUMO

As the 21st century moves forward, it is becoming more and more apparent that the genetic makeup of any individual strongly influences the way they metabolise nutrients. It is very important, therefore, to understand the techniques and technologies used to assess the contribution genes make to the physiology of an individual. Clearly, it is not possible to provide a comprehensive overview, but in the present review an attempt will be made to show, using examples from the authors' research, how these methods have contributed to this understanding. Studies are being undertaken into Fe transport across the placenta, from the mother to the fetus, and the consequences of maternal anaemia on pregnancy outcome. Levels of gene transcript and protein have been measured using Northern and Western blotting respectively. During the course of this work a new protein has been identified using the available human genome database. Following this 'in silico' or 'cyber biology', techniques such as real-time RT-PCR and RNA interference have been used to examine expression of this gene and its protein. The methods used, briefly how they work and some of their limitations will be explained. The objective of the present review is primarily to give a better perception of how molecular biology can be used in research and to help gain a clearer understanding of some of the techniques used.


Assuntos
Anemia Ferropriva/metabolismo , Variação Genética , Ferro/metabolismo , Oxirredutases/metabolismo , Gravidez/metabolismo , Anemia Ferropriva/genética , Anemia Ferropriva/fisiopatologia , Northern Blotting , Western Blotting , Cobre/metabolismo , Desenvolvimento Embrionário e Fetal , Feminino , Humanos , Ferro/deficiência , Troca Materno-Fetal/fisiologia , Oxirredutases/genética , Placenta/metabolismo , Resultado da Gravidez , Reação em Cadeia da Polimerase Via Transcriptase Reversa
15.
Nurs Stand ; 18(48): 38-42, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15366399

RESUMO

Evidence suggests that omega-3 polyunsaturated fatty acids play an integral role in cell membrane function and development of the brain and eyes. Optimising intake appears to confer many benefits, including reduced risk of heart disease and possibly a reduced likelihood of behavioural problems, depression and inflammatory conditions such as rheumatoid arthritis. Although there is some disagreement on what level of intake is optimal, British diets are low in omega-3 fatty acids. Good sources include oily fish and novel sources include fortified eggs and oils derived from microalgae.


Assuntos
Dieta , Ácidos Graxos Ômega-3 , Suplementos Nutricionais , Desenvolvimento Embrionário e Fetal , Feminino , Cardiopatias/prevenção & controle , Humanos , Saúde Mental , Política Nutricional , Gravidez , Cuidado Pré-Natal , Reino Unido
16.
J Cell Biol ; 166(6): 765-8, 2004 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-15353544

RESUMO

GCM proteins constitute a small transcription factor family with a DNA-binding domain exhibiting a novel fold composed of two subdomains rigidly held together by coordination of one of two structural zinc cations. In all known cases, GCM proteins exert the role of master regulators: the prototypical family member determines gliogenesis in Drosophila melanogaster, whereas mammalian GCM proteins orchestrate divergent aspects of development and physiology in placenta, kidney, thymus, and parathyroid gland. Recent data point to an involvement of GCM proteins in different pathological contexts, such as preeclampsia, hyper- or hypoparathyroidism, and parathyroid gland tumors.


Assuntos
Neuropeptídeos/metabolismo , Doenças das Paratireoides/metabolismo , Doenças Placentárias/metabolismo , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Sequência de Aminoácidos , Animais , Proteínas de Ligação a DNA/metabolismo , Desenvolvimento Embrionário e Fetal/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Neuropeptídeos/química , Neuropeptídeos/genética , Gravidez , Ligação Proteica , Estrutura Terciária de Proteína , Transativadores/química , Transativadores/genética , Fatores de Transcrição/química , Fatores de Transcrição/genética , Ativação Transcricional , Zinco/química
19.
Environ Health Perspect ; 112(12): 1225-35, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15345369

RESUMO

Embryonic development is a highly coordinated set of processes that depend on hierarchies of signaling and gene regulatory networks, and the disruption of such networks may underlie many cases of chemically induced birth defects. The antiepileptic drug valproic acid (VPA) is a potent inducer of neural tube defects (NTDs) in human and mouse embryos. As with many other developmental toxicants however, the mechanism of VPA teratogenicity is unknown. Using microarray analysis, we compared the global gene expression responses to VPA in mouse embryos during the critical stages of teratogen action in vivo with those in cultured P19 embryocarcinoma cells in vitro. Among the identified VPA-responsive genes, some have been associated previously with NTDs or VPA effects [vinculin, metallothioneins 1 and 2 (Mt1, Mt2), keratin 1-18 (Krt1-18)], whereas others provide novel putative VPA targets, some of which are associated with processes relevant to neural tube formation and closure [transgelin 2 (Tagln2), thyroid hormone receptor interacting protein 6, galectin-1 (Lgals1), inhibitor of DNA binding 1 (Idb1), fatty acid synthase (Fasn), annexins A5 and A11 (Anxa5, Anxa11)], or with VPA effects or known molecular actions of VPA (Lgals1, Mt1, Mt2, Id1, Fasn, Anxa5, Anxa11, Krt1-18). A subset of genes with a transcriptional response to VPA that is similar in embryos and the cell model can be evaluated as potential biomarkers for VPA-induced teratogenicity that could be exploited directly in P19 cell-based in vitro assays. As several of the identified genes may be activated or repressed through a pathway of histone deacetylase (HDAC) inhibition and specificity protein 1 activation, our data support a role of HDAC as an important molecular target of VPA action in vivo.


Assuntos
Anticonvulsivantes/toxicidade , Desenvolvimento Embrionário e Fetal/efeitos dos fármacos , Perfilação da Expressão Gênica , Histona Desacetilases/genética , Histona Desacetilases/farmacologia , Defeitos do Tubo Neural/diagnóstico , Defeitos do Tubo Neural/fisiopatologia , Análise de Sequência com Séries de Oligonucleotídeos , Toxicogenética/métodos , Ácido Valproico/toxicidade , Animais , Apoptose , Bioensaio/métodos , Biomarcadores/análise , Técnicas de Cultura de Células , Feminino , Humanos , Camundongos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
20.
Exp Cell Res ; 299(2): 415-26, 2004 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-15350540

RESUMO

The periderm is an epithelial layer covering the emerging epidermis in early embryogenesis of vertebrates. In the chicken embryo, an additional cellular layer, the subperiderm, occurs at later embryonic stages underneath the periderm. The questions arose what is the function of both epithelial layers and, as they are transitory structures, by which mechanism are they removed. By immunocytochemistry, the tight junction (TJ) proteins occludin and claudin-1 were localized in the periderm and in the subperiderm, and sites of close contact between adjacent cells were detected by electron microscopy. Using horseradish peroxidase (HRP) as tracer, these contacts were identified as tight junctions involved in the formation of the embryonic diffusion barrier. This barrier was lost by desquamation at the end of the embryonic period, when the cornified envelope of the emerging epidermis was formed. By TUNEL and DNA ladder assays, we detected simultaneous cell death in the periderm and the subperiderm shortly before hatching. The absence of caspases-3, -6, and -7 activity, key enzymes of apoptosis, and the lack of typical morphological criteria of apoptosis such as cell fragmentation or membrane blebbing point to a special form of programmed cell death (PCD) leading to the desquamation of the embryonic diffusion barrier.


Assuntos
Apoptose , Epiderme/crescimento & desenvolvimento , Pele/embriologia , Pele/patologia , Junções Íntimas/química , Animais , Caspases/metabolismo , Galinhas , Claudina-1 , Desenvolvimento Embrionário e Fetal , Células Epidérmicas , Epiderme/química , Peroxidase do Rábano Silvestre/metabolismo , Marcação In Situ das Extremidades Cortadas , Proteínas de Membrana/metabolismo , Ocludina , Junções Íntimas/ultraestrutura
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