Dieta materna influencia reprogramação do DNA do feto

O Setor de Nutrologia da Faculdade de Medicina de Ribeirão Preto (FMRP) da USP divulga estudo da ação do ácido fólico em genes ligados a doenças cardiovasculares e diabetes mellitus tipo 2. Os resultados da pesquisa mostraram que mudanças no fornecimento da vitamina a ratas gestantes e lactantes interferem no controle da expressão gênica das proles para essas doenças.

Manejo del HIV/SIDA en el Embarazo

El control obstétrico de las pacientes y sus implicaciones donde se detalla el historial clínico, estudios cervicovaginal para detectar el estadio clínico de la infección por VIH. Esta guía contiene los pasos para el diagnóstico y tratamiento del SIDA en la mujer embarazada. Aunque es importante mencionar el bajo peso en pacientes infectadas, los tratamientos antirretrovirales permiten una mejoría y expectativas en pacientes infectadas por el VIH.

Morbimortalidad fetoneonatal relacionada con diabetes y embarazo y sus varianciones histomorfológicas placentarias / Fetal neonatal morbidity and mortality associated with diabetes and pregnancy and placental histomorphologic variations

El embarazo asociado a hiperglucemia es en nuestra población uno de los factores de riesgo más importantes, así también en la morbi-mortalidad pre y perinatal. La diabetes incluye dos grandes grupos bien conocidos Tipo I insulinodependiente y Tipo II no insulinodependiente, es necesario aclarar que es vital el control permanente del embarazo en pacientes diabéticas. Nuestro trabajo descriptivo y prospectivo se realizó con el estudio anátomo patológico de 120 placentas en pacientes diabéticas confirmadas distribuidas en grupos: Tipo I, Tipo II y Gestacional. Todas fueron atendidas en consultas prenatales y partos en el Hospital Materno Provincial "Felipe Lucini" de la Ciudad de Córdoba, el estudio se realizó en el Servicio de Patología de la Institución, incluyó macroscopia y microscopia; las placentas fueron coloreadas con H/E, PAS y Masson, y los hallazgos fueron relacionados con la clínica y la bibliografía. De los resultados obtenidos concluimos que en las embarazadas estudiadas en nuestro hospital existen diferencias significativas similares a las encontradas en la literatura. Especialmente en lo referido a edad y tipo de diabetes. Se evidenció que excepto en la diabetes I, se manifestaron similitudes en lo referido al avance de cambios coincidentes con tendencia a la cronicidad. En la gestacional hubo mayor incidencia de macrosomía. Nuestros resultados fueron coincidentes en pacientes mal controladas prenatalmente y en disbalance metabólico. Finalmente las alteraciones patológicas placentarias se encontraron en los tres grupos con variación de intensidades. Cabe concluir que no existen lesiones anátomo-patológicas específicas patognomónicas de Diabetes en las placentas de nuestra casuística...

The morphological observations of some lingual papillae in the prenatal and prepuberal stages of red Sokoto goats (Capra hircus) / Observaciones morfológicas de algunas papilas linguales en las etapas prenatal y prepuberal de cabras rojas de Sokoto (Capra hircus)

This study was carried out to investigate the morphological development of the tongue in the foetal and prepubertal stages of Red Sokoto goats by light microscopy. In foetuses of about 50 days, the tongue tissues showed thickening of the epithelium into about 2-3 layers of cells. In fetuses of about 65 days, mesenchymal tissue was observed under the epithelium.Rudiments of some papillae were observed at this time. Collagenous fibre and blood vessels were scant in the lamina propria. In the 80-day-old foetuses, their was further differentiation of the epithelium rudiments into some papillae and this continued to mature until in foetuses of about 90 and 110 days, were early rudiments of taste buds were observed. Evidence of keratinization was apparent in the prepubertal stages.

El objetivo de este estudio fue investigar el desarrollo morfológico de la lengua en las etapas fetal y prepuberal de la cabra roj a de Sokoto por microscopía de luz. En los fetos de alrededor de 50 días, los tejidos linguales mostraron un engrosamiento del epitelio en cerca de 2-3 capas de células. En los fetos de alrededor de 65 días, se observó tejido mesenquimático bajo el epitelio. Rudimentos de algunas papilas se observaron en esta etapa. Fibras colágenas y vasos sanguíneos fueron observados de manera escasa en la lámina propria. En los 80 días de edad fetal, se observó la mayor diferenciación del epitelio con algunos rudimentos de papilas, lo que continuó hasta la maduración de los fetos, alrededor de los 90 y 110 días, donde fueron observados de manera temprana rudimentos de botones gustativos. Evidencia de queratinización fue evidente en las etapas prepuberales.

Diabetes y Embarazo: contribución de la citomorfología en el diagnostico y tratamiento / Diabetes and pregnancy: contribution of the citomorfología in the diagnosis and tratameinto

INTRODUCCIÓN: Considerando que la diabetes mellitus y sus complicaciones constituyen la tercera causa de muerte en los países industrializados,tendencia en crecimiento continuo(30) , que la diabetes gestacional aumenta el riesgo de diversas complicaciones obstétricas (sufrimiento fetal, macrosomía(36), (suerte intrauterina y problemas neonatales,etc. (24)), que éstas pacientes tienen un riesgo aumentado de morbimortalidad fetal y que probablemente el 60 por ciento de las mismas desarrollarán diabetes en los siguientes 15 años después del parto(28),, en el presente trabajo se analiza las subpoblaciones linfocitarias (CD4 y CD8) como método contribuyente en la detección de diabetes gestacional, y como una herramienta del diagnóstico, tratamiento y seguimiento de los casos, tendiendo a hacer prevenciones sobre el sistema inmunológico. OBJETIVOS de la INVESTIGACIÓN: 1)Detectar variaciones en la subpoblación linfocitaria CD4 y CD8 en pacientes embarazadas, analizando su comportamiento durante el embarazo.2)Evaluar al embarazo como un estado precursor de una futura diabética

Expression of dorsal-ventral genes during early development of Rhynchosciara americana embryos

The establishment of dorsal-ventral polarity in Drosophila is a complex process which involves the action of maternal and zygotically expressed genes. Interspecific differences in the expression pattern of some of these genes have been described in other species. Here we present the expression of dorsal-ventral genes during early embryogenesis in the lower dipteran Rhynchosciara americana. The expression of four genes, the ventralizing genes snail (sna) and twist (twi) and the dorsalizing genes decapentaplegic (dpp) and zerknüllt (zen), was investigated by whole-mount in situ hybridization. Sense and antisense mRNA were transcribed in vitro using UTP-digoxigenin and hybridized at 55°C with dechorionated fixed embryos. Staining was obtained with anti-digoxigenin alkaline phosphatase-conjugated antibody revealed with NBT-BCIP solution. The results showed that, in general, the spatial-temporal expression of R. americana dorsal-ventral genes is similar to that observed in Drosophila, where twi and sna are restricted to the ventral region, while dpp and zen are expressed in the dorsal side. The differences encountered were subtle and probably represent a particular aspect of dorsal-ventral axis determination in R. americana. In this lower dipteran sna is expressed slightly later than twi and dpp expression is expanded over the lateral ectoderm during cellular blastoderm stage. These data suggest that the establishment of dorsal-ventral polarity in R. americana embryos follows a program similar to that observed in Drosophila melanogaster.

Impacts of a new transcription factor family: mammalian GCM proteins in health and disease.

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.

Sequential histone modifications at Hoxd4 regulatory regions distinguish anterior from posterior embryonic compartments.

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.

The G-netics of dark skin.

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.

Fgf18 is required for embryonic lung alveolar development.

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.

NOBOX deficiency disrupts early folliculogenesis and oocyte-specific gene expression.

Primordial ovarian follicles in mice form when somatic cells surround individual oocytes. We show that lack of Nobox, an oocyte-specific homeobox gene, accelerates postnatal oocyte loss and abolishes the transition from primordial to growing follicles in mice. Follicles are replaced by fibrous tissue in female mice lacking Nobox in a manner similar to nonsyndromic ovarian failure in women. Genes preferentially expressed in oocytes, including Oct4 and Gdf9, are down-regulated in Nobox-/- mice, whereas ubiquitous genes such as Bmp4, Kit, and Bax remain unaffected. Therefore, Nobox is critical for specifying an oocyte-restricted gene expression pattern essential for postnatal follicle development.

PTENless means more.

Recent studies indicate that certain key molecules that are vital for various developmental processes, such as Wnt, Shh, and Notch, cause cancer when dysregulated. PTEN, a tumor suppressor that antagonizes the PI3 kinase pathway, is the newest one on the list. The biological function of PTEN is evolutionarily conserved from C. elegans to humans, and the PTEN-controlled signaling pathway regulates cellular processes crucial for normal development, including cell proliferation, soma growth, cell death, and cell migration. In this review, we will focus on the function of PTEN in murine development and its role in regulating stem cell self-renewal and proliferation. We will summarize the organomegaly phenotypes associated with Pten tissue-specific deletion and discuss how PTEN controls organ size, a fundamental aspect of development. Last, we will review the role of PTEN in hormone-dependent, adult-onset mammary and prostate gland development.

Coadaptation in mother and infant regulated by a paternally expressed imprinted gene.

This study investigates how a targeted mutation of a paternally expressed imprinted gene regulates multiple aspects of foetal and post-natal development including placental size, foetal growth, suckling and post-natal growth, weaning age and puberty onset. This same mutation in a mother impairs maternal reproductive success with reduced maternal care, reduced maternal food intake during pregnancy, and impaired milk let-down, which in turn reduces infant growth and delays weaning and onset of puberty. The significance of these coadaptive traits being synchronized in mother and offspring by the same paternally expressed imprinted gene ensures that offspring that have extracted 'good' maternal nurturing will themselves be both well provisioned and genetically predisposed towards 'good' mothering.

Involvement of cadherins 7 and 20 in mouse embryogenesis and melanocyte transformation.

We have determined the expression profiles of cdh7, and the related cdh20 during development. Both transcripts are found in the adult brain, but only cadherin-20 mRNA was detected during embryogenesis. In mouse embryos, cadherin-20 is synthesized by the forebrain, anterior neural ridge, developing visual system, primitive external granular layer of the cerebellum and a subset of neural crest cells likely to develop into melanoblasts. We found that the other embryonic tissues in which cadherin-20 was synthesized depended on genetic background. Melanoma cell lines contained transcripts for cadherin-7 but not for cadherin-20. The majority of the malignant melanoma cell lines produced N-cadherin (N-Cad) and/or cadherin-7 whereas melanocyte cell lines did not. The converse was observed for E-cadherin (E-Cad). Our data suggest that during development cadherin-20 is a key player in compartmentalization of the neural tube and establishment of neural circuitry. Finally, during oncogenesis, cadherin-7, N-cad and E-cad could be used as an efficient marker set for melanoma.

Rearranged genomes of bovine blood cells can allow the development of clones till late fetal stages; but rare unrearranged genomes have greater potential and lead to adulthood.

Cloning via nuclear transfer is promising, but rather inefficient. Moreover, to date, relatively few data are available for a satisfactory phenotypic and genotypic characterization of the clones. Here, we analyze the genomes of clones derived from bovine peripheral blood mononucleated cells (PBMC), known to be composed mainly by lymphocytes. Their genomes are rearranged at either the immunoglobulin (Ig) or the T-cell-receptor (TCR) loci. The DNA of the single survivor and of four aborted fetuses were amplified by semi-quantitative PCR and sequenced. We found the expected rearrangements in DNA from lymphocytes, but neither in DNA from chondrocytes of the survivor, nor in DNA from brain cells of three of the aborted fetuses. This indicates that these four clones derived from somatic cells bearing unrearranged genomes and suggests that in a population of variably differentiated cells those harbouring unrearranged genomes are better donors. Brain cells of the fourth fetus present rearrangements at both loci. The sequences of these rearrangements differ from those obtained from PBMC because they appear unique, thus confirming the clonal origin of the fetus from a cell bearing a rearranged genome. To our knowledge, this is the first example in which both the placenta and the soma of a late fetus are coded for by the rearranged genome of a terminally differentiated cell, unambiguously identified through a specific genetic marker.

Genome activation and developmental block in bovine embryos.

The ultimate goal of in vitro embryo culture systems is to perfectly mimic the condition of oocyte maturation, fertilization and embryo development. These systems are far more complex than standard in vitro cell culture because of the various environments through which the gametes and embryos pass during in vivo development. Improvement of the medium and other culture conditions has allowed for full development of a percentage of the fertilized oocytes but the great majority of bovine zygotes stop developing within a few cell cycles after initiating cleavage. This developmental block arises in the bovine embryo at the eight-cell-stage and is likely correlated with the cytoplasmic quality of the oocyte. Oocytes harbor all mRNAs and proteins needed to reach the fourth or fifth cell cycle, however, embryos that fail to transcribe their own genome fail to further develop. In this article, we review some of the advances in developmental block knowledge and describe a possible role of active embryo transcription that drives incompetent embryos to block and death.

Folate-regulated changes in gene expression in the anterior neural tube of folate binding protein-1 (Folbp1)-deficient murine embryos.

Inactivation of the murine folate binding protein-1 (Folbp1) has been shown to play a vital role in embryonic development. Nullizygous embryos (Folbp1-/-) have significant malformations of the neural tube, craniofacies, and conotruncus, and invariably die in utero by gestational day (E) 10. Administration of 25 mg x kg(-1) x day(-1) folinic acid to dams prior to and throughout gestation rescues the majority of embryos from premature death; however, a portion of surviving embryos develops neural tube defects. Using antisense RNA amplification and cDNA microarrays, we examined the expression of approximately 5700 genes in the anterior neural tube of gestational day 9 Folbp1-/- embryos that were supplemented with folinic acid. Genes that appear to be folate regulated include transcription factors, G-proteins, growth factors, methyltransferases, and those that are related to cell proliferation. The potential impact of such changes during neural tube closure is considered in light of the phenotype of Folbp1-/- embryos.