RESUMO
MicroRNAs (miRNAs) constitute a large family of small noncoding RNAs that are encoded by the genomes of most organisms. They regulate gene expression through posttranscriptional mechanisms to attenuate protein output in various genetic networks. The discovery of miRNAs has transformed our understanding of gene regulation and sparked intense efforts intended to harness their potential as diagnostic markers and therapeutic tools. Over the last decade, a flurry of studies has shed light on placental miRNAs but has also raised many questions regarding the scope of their biologic action. Moreover, the recognition that miRNAs of placental origin are released continually in the maternal circulation throughout pregnancy suggested that circulating miRNAs might serve as biomarkers for placental function during pregnancy. Although this generated much enthusiasm, recently recognized challenges have delayed the application of miRNA-based biomarkers and therapeutics in clinical practice. In this review, we summarize key findings in the field and discuss current knowledge related to miRNAs in the context of placental biology.
Assuntos
MicroRNAs/fisiologia , Doenças Placentárias/genética , Biomarcadores/sangue , Espaço Extracelular/metabolismo , Feminino , Humanos , MicroRNAs/sangue , Doenças Placentárias/sangue , GravidezRESUMO
OBJECTIVES: To determine the correlation between ph at birth and venous Doppler parameters in pregnancies with placental dysfunction. METHODS: This was a prospective cohort study of 58 pregnancies with the diagnosis of placental dysfunction between 26 and 34 weeks of gestation. Inclusion criteria were singleton pregnancies, abnormal umbilical artery (UA) Doppler, fetal growth restriction diagnosed by estimated fetal weight <10th centile for gestational age, intact membranes, and absence of fetal congenital abnormalities. The Doppler measurements were the following: UA pulsatility index (PI), ductus venosus (DV) pulsatility index for veins (PIV), intra-abdominal umbilical vein (UV) time-averaged maximum velocity (TAMxV) and blood flow and left portal vein (LPV) time-averaged maximum velocity (TAMxV) and blood flow. All Doppler parameters were transformed into z-scores (SD values from the mean) according to normative references. RESULTS: The UA pH at birth showed a negative significant correlation with the DV-PIV (p = 0.004) and the DV-PIV z-score (p = 0.004), while LPV TAMxV (p = 0.004), LPV TAMxV z-score (p = 0.002), LPV blood flow (p = 0.01), LPV blood flow normalized (p = 0.04) and UV blood flow (p = 0.04) positively correlated with pH at birth. Multiple regression analysis was performed and the DV-PIV z-score was the variable that independently correlated with pH at birth (p = 0.002). CONCLUSIONS: the present results suggest that changes in fetal venous blood flow, mainly DV and LPV are useful in the management of cases with early onset placental insufficiency and that venous Doppler parameters correlate with pH at birth.
Assuntos
Parto , Doenças Placentárias/diagnóstico por imagem , Ultrassonografia Doppler , Veias Umbilicais/química , Veias Umbilicais/diagnóstico por imagem , Adulto , Feminino , Sangue Fetal/química , Sangue Fetal/metabolismo , Feto/irrigação sanguínea , Humanos , Concentração de Íons de Hidrogênio , Recém-Nascido , Parto/sangue , Parto/metabolismo , Parto/fisiologia , Doenças Placentárias/sangue , Doenças Placentárias/fisiopatologia , Gravidez , Gravidez de Alto Risco/fisiologia , Ultrassonografia Doppler/métodos , Artérias Umbilicais/química , Artérias Umbilicais/diagnóstico por imagem , Artérias Umbilicais/metabolismo , Veias Umbilicais/metabolismo , Adulto JovemRESUMO
La presente revisión trata de la enfermedad trafoblástica gestacional haciendo referencia a los tumores de origen placentario que se derivan del tejido epitelial coriónico. Se describe la clasificación según la OMS, resaltando ls sintomatología clásica de esta patología, así como también los métodos de laboratorio más utilizados como son: La ecosonografía, La dosificación de HCG. Gamagrafía, TAC, estudios de histopatología, medición de alfa feto proteínas dosificación de calcio calmodulina y de CAMP-A quinasa, por último se revisan los esquemas terapéuticos más usados hoy en día.
Assuntos
Humanos , Feminino , Gravidez , Adulto , Luxação Congênita de Quadril/epidemiologia , Luxação Congênita de Quadril/etiologia , Neoplasias , Doenças Placentárias/classificação , Doenças Placentárias/diagnóstico , Luxação Congênita de Quadril , Luxação Congênita de Quadril/terapia , Doenças Placentárias/sangue , Doenças Placentárias/embriologia , Doenças Placentárias/etiologia , Doenças Placentárias/genética , Doenças Placentárias/terapiaRESUMO
La desnutrición temprana induce cambios metabólicos específicos sobre el sistema serotoninergico cerebral, en animales de experimentación. La síntesis de serotonina cerebral se encuentra elevada, lo que depende del incremento de su precursor que es el triptófano plasmático libre; la relación del triptófano unido a albúmina con la fracción libre, determina la disponibilidad del precursor para su paso a través de la barrera hematoencefálica. En el presente estudio reportamos los resultados del metabolismo de la serotonina periférica, en dos grupos de recién nacidos humanos con desnutrición intrauterina y sus controles normales. La fracción libre del L-triptófano fue significativamente elevada, los aminoácidos neutros apresentaron modificaciones substanciales y la fracción unida a albúmina del triptófano y las proteínas del plasma fueron significativamente menores al compararse con los recién nacidos con peso adecuado para la edad gestacional. La elevación de la fracción libre del triptófano plasmático en recién nacidos con desnutrición temprana sugiere un incremento del transporte de esta aminoácido al cerebro con un aumento de la síntesis del neurotransmisor
Assuntos
Humanos , Masculino , Feminino , Aminoácidos/sangue , Doenças Placentárias/sangue , Recém-Nascido/sangue , Serotonina/sangue , Triptofano/sangue , Recém-Nascido PrematuroRESUMO
We measured cord transferrin and ferritin levels in 50 newborn infants with fetal conditions associated with either uteroplacental vascular insufficiency or chronic hypoxia. Sixteen small for gestational age infants, 21 infants of mothers with preeclampsia, and 13 symptomatic infants of diabetic mothers had significantly higher transferrin levels and lower ferritin levels and calculated iron stores than did asymptomatic gestational age-matched control infants without these conditions. Cord ferritin levels and calculated iron stores were significantly lower in the infants of diabetic mothers than in any other group of infants. Cord transferrin levels were inversely correlated with ferritin levels (r = -0.59, P less than 0.001) and were unrelated to transthyretin levels and birth weight in the high-risk infants, but were positively correlated with ferritin levels (r = 0.50, P less than 0.001), transthyretin levels (r = 0.65, P less than 0.001), and birth weight (r = 0.75, P less than 0.001) in the control infants. We conclude that cord transferrin levels do not reflect protein-energy status in newborn infants with prenatal histories suggesting uteroplacental insufficiency or chronic hypoxia, and that when associated with decreased cord ferritin levels, indicate possible impaired iron stores in these infants.
Assuntos
Ferritinas/sangue , Sangue Fetal/análise , Hipóxia Fetal/sangue , Doenças Placentárias/sangue , Insuficiência Placentária/sangue , Transferrina/análise , Doença Crônica , Feminino , Humanos , Hipoglicemia/sangue , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Deficiências de Ferro , Pré-Eclâmpsia/sangue , Gravidez , Gravidez em Diabéticas/sangue , RiscoRESUMO
The purpose of this research was to study the binding capacity of estrogens to the sex hormone-binding globulin (SHBG) in mothers and their intrauterine malnourished newborns. Blood samples were obtained from mothers at delivery, and from babies, of the umbilical cord. SHBG was measured according to the method of Mickelson and Petra. It was found in mothers of malnourished babies that the binding capacity of serum protein to dehydrotestosterone (DHT) was significantly decreased in comparison to the controls (10.63 +/- 1.61 vs 13.25 +/- 2.18 micrograms DHT/dl serum, respectively), whereas it was significantly increased in intrauterine malnourished newborns (1.01 +/- 0.24 vs 0.77 +/- 0.18, respectively). These results suggest that SHBG decrease in mothers of intrauterine malnourished newborns occurs due to a decrease in the production of fetal adrenal hormone precursors and may, therefore, be a compensating mechanism to increase placental flow.
Assuntos
Doenças Placentárias/sangue , Insuficiência Placentária/sangue , Período Pós-Parto , Globulina de Ligação a Hormônio Sexual/análise , Feminino , Sangue Fetal/análise , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , GravidezAssuntos
Humanos , Feminino , Gravidez , Doenças Placentárias/sangue , Sistema do Grupo Sanguíneo Rh-HrRESUMO
Dysmaturity, diagnosed according to the Clifford criteria, was studied for the first time in a black population. The infants and matched control subjects were participants in the Collaborative Perinatal Study in Philadelphia from birth to 7 years of age. The incidence of dysmaturity was 25/1,000 live births; more boys than girls were born dysmature, reversing the normal male/female ratio found among black infants in the Collaborative Study as a whole. The condition was more common among post-term infants but did occur in earlier gestational weeks. The overall characteristics of the condition among this black population did not differ from those previously reported among white populations of various races. Surviving infants developed mentally and physically as well as control subjects. No prenatal or environmental characteristics were found that distinguished mothers of dysmature infants from those of nondysmature infants.
Assuntos
Recém-Nascido , Criança Pós-Termo , Índice de Apgar , Bilirrubina/sangue , População Negra , Criança , Pré-Escolar , Feminino , Seguimentos , Idade Gestacional , Hematócrito , Humanos , Lactente , Recém-Nascido Pequeno para a Idade Gestacional , Masculino , Idade Materna , Mecônio , Paridade , Pennsylvania , Placenta/patologia , Doenças Placentárias/sangue , Doenças Placentárias/mortalidade , Doenças Placentárias/patologia , Gravidez , Testes Psicológicos , Dermatopatias/sangue , Dermatopatias/mortalidade , Síndrome , Verniz CaseosoRESUMO
With the technique of single inulin injection, the speed of glomerular filtration (GFR) was evaluated in 16 healthy newborns and in 29 in-utero malnourished infants. The GFR was of 30.22 +/- 10.23 ml/min/1.73 m2 for healthy infants and of 41.86 +/- 17.63 for malnourished cases (p greater than 0.05). When full term infants were compared with pre-term, no difference was shown (p greater than 0.05) either in the healthy group as in the malnourished. The most important finding was that malnourished infants with hematocrit greater than or equal to 60, showed decrease in GFR as compared with those whose hematocrits were less than or equal to 58; likewise, the correlation coefficient of the hematocrit with GFR was inverse and significant (p less than 0.001).
Assuntos
Taxa de Filtração Glomerular , Doenças Placentárias/fisiopatologia , Peso ao Nascer , Feminino , Idade Gestacional , Hematócrito , Humanos , Lactente , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Prematuro , Doenças Placentárias/sangue , GravidezRESUMO
The per centum distribution of T and B lymphocytes was determined in 30 full term newborns showing adequate development for their gestational age and in 42 full term newborns showing in utero malnutrition. A significant decrease (p less than 0.001) of both lymphocytic subpopulations was found in the in utero malnutrition group. The possibility of a decreased efficiency of the immune response in this group of patients is discussed.