Regeneration in Experimental Alveolar Bone Defect Using Human Umbilical Cord Mesenchymal Stem Cells.

Cleft lip and palate is a congenital disorder including cleft lip, and/or cleft palate, and/or alveolar cleft, with high incidence.The alveolar cleft causes morphological and functional abnormalities. To obtain bone bridge formation and continuous structure between alveolar clefts, surgical interventions are performed from infancy to childhood. However, desirable bone bridge formation is not obtained in many cases. Regenerative medicine using mesenchymal stem cells (MSCs) is expected to be a useful strategy to obtain sufficient bone bridge formation between alveolar clefts. In this study, we examined the effect of human umbilical cord-derived MSCs by transplantation into a rat experimental alveolar cleft model. Human umbilical cords were digested enzymatically and the isolated cells were collected (UC-EZ cells). Next, CD146-positive cells were enriched from UC-EZ cells by magnetic-activated cell sorting (UC-MACS cells). UC-EZ and UC-MACS cells showed MSC gene/protein expression, in vitro. Both cells had multipotency and could differentiate to osteogenic, chondrogenic, and adipogenic lineages under the differentiation-inducing media. However, UC-EZ cells lacked Sox2 expression and showed the lower ratio of MSCs than UC-MACS cells. Thus, UC-MACS cells were transplanted with hydroxyapatite and collagen (HA + Col) into alveolar cleft model to evaluate bone formation in vivo. The results of micro computed tomography and histological staining showed that UC-MACS cells with HA + Col induced more abundant bone formation between the experimental alveolar clefts than HA + Col implantation only. Cells immunopositive for osteopontin were accumulated along the bone surface and some of them were embedded in the bone. Cells immunopositive for human-specific mitochondria were aligned along the newly formed bone surface and in the new bone, suggesting that UC-MACS cells contributed to the bone bridge formation between alveolar clefts. These findings indicate that human umbilical cords are reliable bioresource and UC-MACS cells are useful for the alveolar cleft regeneration.

Effects of the Insulted Neuronal Cells-Derived Extracellular Vesicles on the Survival of Umbilical Cord-Derived Mesenchymal Stem Cells following Cerebral Ischemia/Reperfusion Injury.

Umbilical cord-derived mesenchymal stem cells (UC-MSCs) engraftment is a potential therapy for cerebral ischemic stroke. However, the harsh microenvironment induced by cerebral ischemia/reperfusion restricts the survival rate and therapeutic efficiency of the engrafted UC-MSCs. In this study, we explored whether small extracellular vesicles (EVs) derived from injured neuronal cells following exposure to cerebral ischemia/reperfusion insult affect the survival of transplanted UC-MSCs. To establish a simulation of cerebral ischemia/reperfusion microenvironment comprising engrafted UC-MSCs and neuronal cells, we cocultured EVs derived from injured N2A cells, caused by exposure to oxygen-glucose deprivation and reperfusion (OGD/R) insult, with UC-MSCs in a conditioned medium. Coculture of UC-MSCs with EVs exacerbated the OGD/R-induced apoptosis and oxidative stress. Suppression of EVs-release via knock-down of Rab27a effectively protected the UC-MSCs from OGD/R-induced insult. Moreover, hypoxia preconditioning not only elevated the survival of UC-MSCs but also improved the paracrine mechanism of injured N2A cells. Altogether, these results show that EVs from injured N2A cells exacerbates OGD/R-induced injury on transplanted UC-MSCs in vitro. Hypoxia preconditioning enhances the survival of the engrafted-UC-MSCs; hence, thus could be an effective approach for improving UC-MSCs therapy in ischemic stroke.

Associação entre as características macroscópicas do cordão umbilical, gestação de alto risco e repercussões neonatais / Asociación entre las características macroscópicas del cordón umbilical, gestación de alto riesgo y repercusiones neonatales / Association between the macroscopic characteristics of the umbilical cord, high-risk pregnancy and neonatal repercussions

RESUMO Objetivo Verificar a associação entre as características macroscópicas do cordão umbilical, a gestação de alto risco e as repercussões neonatais. Método Estudo transversal, realizado no período de janeiro de 2012 a janeiro de 2015 em uma maternidade pública de Goiânia/GO. A população foi constituída de 126 puérperas com diagnóstico de gestação de alto risco e 139 clinicamente normais (grupo controle). Foram avaliadas características macroscópicas do cordão umbilical, doenças de base maternas, fetais e neonatais, idade gestacional, índice de Apgar, peso ao nascer, perímetro cefálico e paridade. Os dados foram analisados descritivamente. Resultados Participaram do estudo 265 puérperas e seus respectivos recém-nascidos. As características mais frequentes do cordão umbilical de puérperas com gestação de alto risco e grupo controle foram a ausência de nós verdadeiros (97,6% e 2,4%, respectivamente), comprimento entre 35 e 70 centímetros e inserção paracentral (81,7% e 18,3%). Houve diferença estatística entre o grupo gestação de alto risco e extremos de idade materna (p=0,004). Conclusão A análise e a descrição das características do cordão umbilical, realizadas pelo/a enfermeiro/a, trazem informações importantes sobre o prognóstico neonatal. Essa atribuição subsidia a prática clínica e visa à segurança ao binômio durante todo o período perinatal.

RESUMEN Objetivo Verificar la asociación entre las características macroscópicas del cordón umbilical, gestación de alto riesgo y repercusiones neonatales. Método Estudio transversal, realizado en el período de enero de 2012 a enero de 2015 en una maternidad pública de Goiânia/GO. La población estuvo constituida de 126 puérperas con diagnóstico de gestación de alto riesgo y 139 clínicamente normales (grupo control). Fueron evaluadas características macroscópicas del cordón umbilical, enfermedades de base maternas, fetales y neonatales, edad gestacional, índice de Apgar, peso al nacer, perímetro cefálico y paridad. Los datos fueron analizados descriptivamente. Resultados Participaron en el estudio 265 puérperas y sus respectivos recién nacidos. Las características más frecuentes del cordón umbilical de puérperas con gestación de alto riesgo y grupo control fueron la ausencia de nudos verdaderos (el 97,6% y el 2,4%, respectivamente), longitud entre 35 y 70 centímetros e inserción paracentral (el 81,7% y el 18,3%). Hubo diferencia estadística entre el grupo gestación de alto riesgo y extremos de edad materna (p=0,004). Conclusión El análisis y la descripción de las características del cordón umbilical, realizadas por el/la enfermero/a, brindan informaciones importantes acerca del pronóstico neonatal. Dicha atribución subsidia la práctica clínica y tiene como fin la seguridad del binomio durante todo el período perinatal.

ABSTRACT Objective To verify the association between the macroscopic characteristics of the umbilical cord, high-risk pregnancy and neonatal repercussions. Method A cross-sectional study carried out from January 2012 to January 2015 in a public maternity hospital in Goiânia/GO. The study population consisted of 126 recent puerperal women with diagnosis of high-risk pregnancy, and 139 clinically normal women (control group). Macroscopic features of the umbilical cord, maternal, fetal and neonatal diseases, gestational age, Apgar score, birth weight, head circumference and parity were evaluated. Data were descriptively analyzed. Results 265 puerperal women and their respective newborns participated in the study. The most frequent characteristics of the umbilical cord of those with high-risk pregnancy and those from the control group were the absence of true knots (97.6% and 2.4%, respectively), length between 35 and 70 centimeters and paracentral insertion (81.7% and 18.3%). A statistical difference was observed between the high-risk pregnancy group and extremes of maternal age (p=0.004). Conclusion The analysis and description of the characteristics of the umbilical cord carried out by the nurse lend important information about the neonatal prognosis. This evaluation subsidizes clinical practice and seeks to ensure the safety of the (mother-baby) binomial throughout the perinatal period.

Prenatal and Postnatal Clinical Course of an Urachus Identified as an Allantoic Cyst in the Umbilical Cord.

PURPOSE: The aim of this study was to clarify the prenatal and postnatal clinical courses of an urachus identified as an allantoic cyst in the umbilical cord. METHODS: Allantoic cysts in the umbilical cord were identified in five fetuses over the past 12 years at our hospital. The prenatal and postnatal clinical courses of these patients were retrospectively reviewed. RESULTS: The presence of allantoic cysts in the umbilical cord was first detected at 15 to 27 weeks of gestation. The cysts subsequently became enlarged, reaching a maximum diameter of 34 to 61 mm at 17 to 32 weeks of gestation. The cysts then suddenly disappeared due to spontaneous rupture at 26 to 35 weeks of gestation. After being born at 38 (35-39) weeks of gestation, four patients were diagnosed with a patent urachus requiring surgery in the infantile period and one was diagnosed with an urachal cyst, which is currently being observed without surgery. CONCLUSION: The presence of an urachus identified as an allantoic cyst in the umbilical cord is frequently associated with spontaneous rupture during the prenatal period, resulting in a patent urachus after birth that requires surgical intervention.

Propranolol during pregnancy for large chorioangioma.

Large chorioangiomas are frequently associated with adverse perinatal outcome. Its treatment remains invasive and controversial. Infantile hemangiomas which have numerous similarities with chorioangiomas are now usually treated with propranolol. This drug has been extensively used with a good tolerance during pregnancy in other indications. We report the first use of propranolol with the aim of limiting the increase in chorioangioma volume and avoiding the associated complications. The observed inhibition of the growth of the chorioangioma after introduction of propranolol argues for further evaluation of this treatment in this indication.

The Ovine Fetal and Placental Inflammatory Response to Umbilical Cord Occlusions With Worsening Acidosis.

We hypothesized that repetitive umbilical cord occlusions (UCOs) leading to severe acidemia will stimulate a placental and thereby fetal inflammatory response which will be exacerbated by chronic hypoxemia and low-grade bacterial infection. Chronically instrumented fetal sheep served as controls or underwent repetitive UCOs for up to 4 hours or until fetal arterial pH was <7.00. Normoxic-UCO and hypoxic-UCO fetuses had arterial O2 saturation pre-UCOs of >55% and <55%, respectively, while lipopolysaccharide (LPS)-UCO fetuses received LPS intra-amniotic (2 mg/h) starting 1 hour pre-UCOs. Fetal plasma and amniotic fluid were sampled for interleukin (IL) 6 and IL-1ß. Animals were euthanized at 48 hours of recovery with placental cotyledons processed for measurement of macrophage, neutrophil, and mast cell counts. Repetitive UCOs resulted in severe fetal acidemia with pH approaching 7.00 for all 3 UCO groups. Neutrophils, while unchanged within the cotyledon fetal and intermediate zones, were ∼2-fold higher within the zona intima for all 3 UCO groups. However, no differences were observed in macrophage counts among the treatment groups and no cotyledon mast cells were seen. Fetal plasma and amniotic fluid cytokines remained little changed post-UCOs and/or at 1 and 48 hours of recovery in the normoxic-UCO and hypoxic-UCO groups but increased several fold in the LPS-UCO group with IL-6 plasma values at 1 hour recovery highly correlated with the nadir pH attained (r = -.97). As such, repetitive UCOs with severe acidemia can induce a placental inflammatory response and more so with simulated low-grade infection and likely contributing to cytokine release in the umbilical circulation.

Maternal pregravid obesity changes gene expression profiles toward greater inflammation and reduced insulin sensitivity in umbilical cord.

BACKGROUND: Maternal obesity is associated with unfavorable outcomes, which may be reflected in the as yet undiscovered gene expression profiles of the umbilical cord (UC). METHODS: UCs from 12 lean (pregravid BMI < 24.9) and 10 overweight/obese (pregravid BMI ≥ 25) women without gestational diabetes were collected for gene expression analysis using Human Primeview microarrays. Metabolic parameters were assayed in mother's plasma and cord blood. RESULTS: Although offspring birth weight and adiposity (at 2 wk) did not differ between groups, expression of 232 transcripts was affected in UC from overweight/obese compared with those of lean mothers. Gene-set enrichment analysis revealed an upregulation of genes related to metabolism, stimulus and defense response, and inhibitory to insulin signaling in the overweight/obese group. We confirmed that EGR1, periostin, and FOSB mRNA expression was induced in UCs from overweight/obese mothers, while endothelin receptor B, KLF10, PEG3, and EGLN3 expression was decreased. Messenger RNA expression of EGR1, FOSB, MEST, and SOCS1 were positively correlated (P < 0.05) with mother's first-trimester body fat mass (%). CONCLUSION: Our data suggest a positive association between maternal obesity and changes in UC gene expression profiles favoring inflammation and insulin resistance, potentially predisposing infants to develop metabolic dysfunction later on in life.

Amniotomy and cord prolapse.

Research shows that artificially rupturing the amniotic sac (amniotomy) can cause umbilical cord prolapse. Amniotomy became a routine part of obstetrical care with the introduction of active management, without evidence of benefit. In the 30 years since active management was introduced, the rate at which amniotomy causes umbilical cord prolapse has not been directly studied. Two controlled studies from Turkey from 2002 and 2006 are the only published studies that provide enough data to extract the rate at which cord prolapse follows amniotomy. They show that 1 cord prolapse results from every 300 amniotomies (0.3%). There is data suggesting amniotomy may also increase neonatal GBS infection, maternal pain and fetal blood loss if placental blood vessels are punctured.

The impact of intermittent umbilical cord occlusions on the inflammatory response in pre-term fetal sheep.

Fetal hypoxic episodes may occur antepartum with the potential to induce systemic and cerebral inflammatory responses thereby contributing to brain injury. We hypothesized that intermittent umbilical cord occlusions (UCOs) of sufficient severity but without cumulative acidosis will lead to a fetal inflammatory response. Thirty-one chronically instrumented fetal sheep at ∼0.85 of gestation underwent four consecutive days of hourly UCOs from one to three minutes duration for six hours each day. Maternal and fetal blood samples were taken for blood gases/pH and plasma interleukin (IL)-1ß and IL-6 levels. Animals were euthanized at the end of experimental study with brain tissue processed for subsequent counting of microglia and mast cells. Intermittent UCOs resulted in transitory fetal hypoxemia with associated acidemia which progressively worsened the longer umbilical blood flow was occluded, but with no cumulative blood gas or pH changes over the four days of study. Fetal arterial IL-1ß and IL-6 values showed no significant change regardless of the severity of the UCOs, nor was there any evident impact on the microglia and mast cell counts for any of the brain regions studied. Accordingly, intermittent UCOs of up to three minutes duration with severe, but limited fetal hypoxemia and no cumulative acidemia, do not result in either a systemic or brain inflammatory response in the pre-term ovine fetus. However, fetal IL-1B and IL-6 values were found to be well correlated with corresponding maternal values supporting the placenta as a primary source for these cytokines with related secretion into both circulations. Female fetuses were also found to have higher IL-1ß levels than males, indicating that gender may impact on the fetal inflammatory response to various stimuli.

Células progenitoras hematopoyéticas de sangre de cordón umbilical / Hematopoietic progenitor cells from umbilical cord blood

La sangre de cordón umbilical (SCU) es una rica fuente de células progenitoras hematopoyéticas (CPH) para el trasplante. Se describe la historia del uso de la SCU para trasplante hematopoyético y la necesidad del consentimiento informado para su obtención, conservación, almacenamiento y uso con estos fines. Se hace referencia a la seguridad para el receptor en cuanto a selección, requisitos epidemiológicos, obstétricos y analíticos de la muestra, la calidad hematopoyética de la colecta y procesamiento hasta su conservación, así como a las ventajas y desventajas de su uso en el trasplante. Por último, se aborda la importancia de incrementar en los bancos de SCU, el almacenamiento de CPH que tengan representación antigénica compatible con las minorías étnicas

The umbilical cord blood (UCB) is a rich source of hematopoietic progenitor cells (HPC) for transplantation. Here, we describe the history of using of UCB for hematopoietic transplantation and the need of obtaining informed consent for its conservation, storage and further use for these purposes. Reference is made to the security for the receiver in terms of sample selection, epidemiological, obstetrical, and analytical requirements, as well as the quality of hematopoietic collection and processing for preservation, in addition to the advantages and disadvantages of its use in transplantation. Finally, we address the importance of increasing the UCB banks, storing CPH with antigenic representation compatible with ethnic minorities

Systemic and cerebral inflammatory response to umbilical cord occlusions with worsening acidosis in the ovine fetus.

OBJECTIVE: We hypothesized that repetitive umbilical cord occlusions (UCOs) with worsening acidosis will lead to a fetal inflammatory response. STUDY DESIGN: Chronically instrumented fetal sheep underwent a series of UCOs until fetal arterial pH decreased to <7.00. Maternal and fetal blood samples were taken for blood gases/pH and plasma interleukin (IL)-1B and IL-6 levels. Animals were euthanized at 24 hours of recovery with brain tissue processed for subsequent measurement of microglia and mast cell counts. RESULTS: Repetitive UCOs resulted in a severe degree of fetal acidemia. Fetal plasma IL-1B values were increased approximately 2-fold when measured at maximal fetal acidosis and again at 1-2 hours of recovery. Fetal microglia cells were increased approximately 2-fold in the white matter and hippocampus, while mast cells were increased approximately 2-fold in the choroid plexus and now evident in the thalamus when analyzed at 24 hours recovery. CONCLUSION: Repetitive UCOs leading to severe acidemia in the ovine fetus near term will result in an inflammatory response both systemically and locally within the brain.

Mild chronic hypoxia modifies the fetal sheep neural and cardiovascular responses to repeated umbilical cord occlusion.

We have shown that 5 days of mild hypoxia has significant effects on fetal ECoG activity, heart rate and blood pressure. We now studied if mild prolonged hypoxemia had an adverse effect on the fetal cardiovascular and neural responses to repeated cord occlusion and on the magnitude of neuronal damage. Fetal and maternal catheters were placed at 120 days' gestation and animals allocated at random to receive intratracheal maternal administration of nitrogen (n=8) or compressed air in controls (n=7). Five days after surgery, nitrogen infusion was adjusted to reduce fetal brachial artery pO(2) by 25%. After 5 days of chronic hypoxemia, the umbilical cord was completely occluded for 5 min every 30 min for a total of four occlusions. Data are presented as mean+/-SEM and were analyzed by two-way ANOVA or two-sample t-test. Nitrogen infusion decreased fetal pO(2) by 26% (20.5+/-1.7 vs. 14.3+/-0.8 mm Hg) without changing fetal pCO(2) or pH. Pre-existing hypoxia fetuses had a greater terminal fall in heart rate in occlusions II, III and IV, and also had a more severe terminal hypotension in the final occlusion. Pre-existing hypoxia was associated with a greater fall in spectral edge frequency during occlusions from 14.4+/-0.9 Hz to 6.9+/-0.4 Hz vs. 13.6+/-1.64 Hz to 10.6+/-0.77 Hz in controls, p<0.05. In addition, during the three-day post-occlusion period, the contribution of theta and alpha band frequencies to total ECoG activity was significantly lower in the pre-existing hypoxia fetuses (p<0.05). These effects were associated with increased neuronal loss in the striatum (p<0.05). In summary, the cardiovascular and neural response indicates a detrimental effect of pre-existing mild hypoxia on fetal outcome following repeated umbilical cord occlusions.

Cierre diferido en onfalocele no roto: reporte de un caso / Close deferred not broken in omphalocele: a case report

El término onfalocele fue definido por Benson en 1949 y se atribuye a Paré su descripción inicial en la primera mitad del siglo XVI. Se trata de una herniación de las vísceras abdominales que están cubiertas por un saco formado por peritoneo, membrana amniótica y gelatina de Warthon y que se continúa con el cordón umbilical. (1) Esta herniación es consecuencia de una alteración en la formación de la pared abdominal anterior del embrión. El defecto se sitúa soempre en la región umbilical y puede ser de tamaño variable, considerándose un onfalocele gigante cuando el defecto supera los 10 cm. Generalmente contiene asas de intestino delgado, y en los de mayor tamaño, el hígado. (2) La presencia de otras malformaciones asociadas no es rara y puede condicionar el pronóstico del recién nacido. El 25 por ciento presentan una cardiopatía congénita, siendo más frecuente la tetralogía de Fallot. La frecuencia de esta entidad varía de unas regiones a otras y oscila entre 1/6.000 hasta 1/60.000 de los recién nacidos vivos, incluyendo los casos de gastrosquitis. Puede diagnosticarse mediante las ecografías prenatales a partir del cuarto mes, y en un futuro serán subsidiarias de corregirse mediante cirugía fetal. (3) Existe controversia en relación a la necesidad de una cesárea programada para el nacimiento. La cesárea previene la lesión de las vísceras herniadas, pero el parto vaginal logra una mayor madurez del feto. En general los niños afectados de onfaloceles grandes deben nacer mediante cesárea electiva, pero los que presentan onfaloceles pequeños pueden nacer mediante parto vaginal. Con independencia de la decisión adoptada es importante que los neonatólogos y cirujanos pediátricos estén alertados del nacimiento para realizar una adecuada valoración del recién nacido lo antes posible. El tratamiento tiene por misión reintroducir las vísceras en la cavidad abdominal restaurando la integridad de la misma antes de que se produzca la contaminación del contenido herniario.

Predictors of neonatal outcome in early-onset placental dysfunction.

OBJECTIVE: To identify specific estimates and predictors of neonatal morbidity and mortality in early onset fetal growth restriction due to placental dysfunction. METHODS: Prospective multicenter study of prenatally diagnosed growth-restricted liveborn neonates of less than 33 weeks of gestational age. Relationships between perinatal variables (arterial and venous Dopplers, gestational age, birth weight, acid-base status, and Apgar scores) and major neonatal complications, neonatal death, and intact survival were analyzed by logistic regression. Predictive cutoffs were determined by receiver operating characteristic curves. RESULTS: Major morbidity occurred in 35.9% of 604 neonates: bronchopulmonary dysplasia in 23.2% (n=140), intraventricular hemorrhage in 15.2% (n=92), and necrotizing enterocolitis in 12.4% (n=75). Total mortality was 21.5 % (n=130), and 58.3% survived without complication (n=352). From 24 to 32 weeks, major morbidity declined (56.6% to 10.5%), coinciding with survival that exceeded 50% after 26 weeks. Gestational age was the most significant determinant (P<.005) of total survival until 26(6/7) weeks (r(2)=0.27), and intact survival until 29(2/7) weeks (r(2)=0.42). Beyond these gestational-age cutoffs, and above birth weight of 600 g, ductus venosus Doppler and cord artery pH predicted neonatal mortality (P<.001, r(2)=0.38), and ductus venosus Doppler alone predicted intact survival (P<.001, r(2)=0.34). CONCLUSION: This study provides neonatal outcomes specific for early-onset placenta-based fetal growth restriction quantifying the impact of gestational age, birth weight, and fetal cardiovascular parameters. Early gestational age and birth weight are the primary quantifying parameters. Beyond these thresholds, ductus venosus Doppler parameters emerge as the primary cardiovascular factor in predicting neonatal outcome. LEVEL OF EVIDENCE: II.

Gasimetria do cordão umbilical: quando e por quê? / Umbilical cord gas: when and why?

O diagnóstico preciso de hipóxia perinatal é motivo de controvérsias na literatura. O índice de Apgar tem sido amplamente utilizado, entretanto gera conflitos quanto ao seu valor preditivo em relação ao estado neurológico fetal. Vários estudos vêm sendo desenvolvidos e preconizam a análise da gasimetria do cordão umbilical como um dado preciso e objetivo...

Circular cervical revisitada / Nuchal cord revisited

O Presente trabalho procurou identificar na literatura a existência de possíveis evidências científicas capazes de esclarecer o significado clínico e as implicações da presença da circular cervical durante a gravidez. A maioria dos trabalhos relacionados nesta revisão sugere a presença de comprometimento do bem-estar fetal, entretanto os dados não apresentam significância estatística na sua totalidade e carecem de rigor científico. Por outro lado, é nítida a carência de trabalhos que confirmam a inexistência destas complicações quando a circular cervical está presente. Com base nesta revisão, os autores sugerem conduta clínica para o acompanhamento das gravidezes com circular cervical, adequando-as às situações de baixo e de alto risco gestacional

Correlação da área do cordão umbilical com parâmetros antropométricos em gestações normais / Correlation between umbilical cord cross-sectional area and normal anthropometric parameters in normal pregnancies

OBJETIVO: Este objetivou aferir a área de secção transversa do cordão umbilical (ASTCU) em gestações normais, com idade gestacional entre 20 e 40 semanas, para a construção de uma curva de valores normais para tal parâmetro. MATERIAIS E MÉTODOS: Foi realizado estudo transversal para determinar os valores de referência para a ASTCU em gestações normais (pacientes com datas precisas da última menstruação e exame ultra-sonográfico realizado antes da 20ª semana, sem qualquer doença conhecida). As medidas da ASTCU foram obtidas em plano adjacente à inserção do cordão umbilical no abdome. Os aparelhos de ultra-som utilizados foram da marca Synergy Multi Sync M500, Toshiba 140 e Toshiba Corevision, todos com transdutores transabdominais de 3,5 MHz. A análise estatística foi realizada pelo programa SPSS (Statistical Package for Social Sciences). RESULTADOS: Os dados obtidos foram considerados normais pelo teste de Kolmogorov-Smirnov e a curva de normalidade foi calculada por regressão linear. A análise de variância obtida pelo teste F (F = 356,27) mostrou que o modelo de regressão foi significativo ao nível de p < 0,01, mostrando que a curva estudou corretamente a população recrutada e que o intervalo de confiança (95 por cento) continha o valor real da ASTCU. A equação de regressão encontrada para a ASTCU (y), de acordo com a idade gestacional (x), foi: y = -532,27 + 44,358x - 0,655x². CONCLUSÃO: Obtivemos uma curva de valores normais da ASTCU que mostra um crescimento progressivo de seus valores até a 32ª semana, seguida por um período de estabilização até a 34ª semana e uma queda de seus valores a partir da 35ª semana.

OBJECTIVE: To develop a nomogram for the umbilical cord cross-sectional area (UCCSA) in normal pregnancies in women between 20 to 40 weeks gestation. MATERIALS AND METHODS: A cross-sectional study was developed to determine reference ranges for the UCCSA during normal pregnancies (patients with known dates of last menstrual period, and a normal ultrasound examination before the 20th week of gestation). The measurements of the UCCSA were obtained using a plane adjacent to the insertion of the cord in the abdomen. A 3.5 MHz transabdominal transducer was used on all ultrasound equipment utilized (a Synergy Multi Sync M500, a Toshiba 140 and a Toshiba Corevision). The statistical analysis was performed using the SPSS (Statistical Package for Social Sciences) software. RESULTS: The Kolmogorov-Smirnov test showed a normal distribution of the data and the nomogram was constructed by linear regression. The analysis of variance (F test = 356.27) showed that our model was significant at a p < 0.01 level, and therefore represented adequately the studied population. The confidence interval (95%) contained the real value of the UCCSA. The equation constructed for the UCCSA (y) according to the gestational age (x) was: y = –532.27 + 44.358x – 0,655x². CONCLUSION: The nomogram developed for the UCCSA shows a progressive increase of the UCCSA up to the 32nd week, stabilization until the 34th week, and decrease after the 35th week of gestation.

Key neuroprotective role for endogenous adenosine A1 receptor activation during asphyxia in the fetal sheep.

BACKGROUND AND PURPOSE: The fetus is well known to be able to survive prolonged exposure to asphyxia with minimal injury compared with older animals. We and others have observed a rapid suppression of EEG intensity with the onset of asphyxia, suggesting active inhibition that may be a major neuroprotective adaptation to asphyxia. Adenosine is a key regulator of cerebral metabolism in the fetus. METHODS: We therefore tested the hypothesis that infusion of the specific adenosine A1 receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine (DPCPX), given before 10 minutes of profound asphyxia in near-term fetal sheep, would prevent neural inhibition and lead to increased brain damage. RESULTS: DPCPX treatment was associated with a transient rise and delayed fall in EEG activity in response to cord occlusion (n=8) in contrast with a rapid and sustained suppression of EEG activity in controls (n=8). DPCPX was also associated with an earlier and greater increase in cortical impedance, reflecting earlier onset of primary cytotoxic edema, and a significantly smaller reduction in calculated cortical heat production after the start of cord occlusion. After reperfusion, DPCPX-treated fetuses but not controls developed delayed onset of seizures, which continued for 24 hours, and sustained greater selective hippocampal, striatal, and parasagittal neuronal loss after 72-hour recovery. CONCLUSIONS: These data support the hypothesis that endogenous activation of the adenosine A1 receptor during severe asphyxia mediates the initial suppression of neural activity and is an important mechanism that protects the fetal brain.