RESUMO
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 JovemAssuntos
Aleitamento Materno/efeitos adversos , Exposição Ambiental/efeitos adversos , Intoxicação por Chumbo/etiologia , Leite Humano/química , Pré-Escolar , Feminino , Seguimentos , Humanos , Incidência , Lactente , Recém-Nascido , Intoxicação por Chumbo/epidemiologia , Intoxicação por Chumbo/prevenção & controle , Masculino , Leite Humano/metabolismo , Gravidez , Medição de Risco , Artérias Umbilicais/químicaRESUMO
Umbilical veins (UV) and arteries (UA) of preeclamptic women in Curaçao harbor lower long-chain polyunsaturated fatty acids (LCP). The present aim was to test these findings in Mwanza (Tanzania), whose inhabitants have high LCPomega3 and LCPomega6 intakes from Lake Victoria fish. Women with preeclampsia (n=28) in Mwanza had lower PUFA and higher 20:0 in UV and UA, compared with normotensive/non-proteinuric controls (n=31). Their UV 22:6omega3, 22:4omega6, LCPomega6, omega6, and LCPomega3+omega6 were lower, while saturated FA, potentially de novo synthesized FA (Sigmade novo) and (Sigmade novo)/(LCPomega3+omega6) ratio were higher. Their UA had higher 16:1omega7, omega7, 18:0, and 16:1omega7/16:0. Umbilical vessels in Mwanza had higher 22:6omega3, LCPomega3, omega3, and 16:0, and lower 22:5omega6, 20:2omega6, 18:1omega9, and omega9, compared to those in Curaçao. Preeclampsia in both Mwanza and Curaçao is characterized by lower LCP and higher Sigmade novo. An explanation of this might be placental dysfunction, while the similarity of umbilical vessel FA-abnormalities in preeclamptic and diabetic pregnancies suggests insulin resistance as a common denominator.
Assuntos
Ácidos Graxos Ômega-3/análise , Ácidos Graxos Ômega-6/análise , Ácidos Graxos/análise , Produtos Pesqueiros , Pré-Eclâmpsia/metabolismo , Cordão Umbilical/química , Adolescente , Adulto , Gorduras Insaturadas na Dieta/metabolismo , Ácidos Graxos Insaturados/análise , Feminino , Humanos , Antilhas Holandesas , Gravidez , Tanzânia , Artérias Umbilicais/química , Veias Umbilicais/química , Adulto JovemRESUMO
OBJECTIVE: To identify K+ channels of smooth muscle of human umbilical artery using the patch-clamp technique and to study their effect on resting tone of umbilical artery rings. METHODS: Whole-cell and single-channel patch-clamp recordings in enzymatically isolated smooth muscle cells were made. Measurements of developed isometric force were performed on intact tissue. RESULTS: Delayed rectifier K+ channels (KDR) and large-conductance Ca2+-activated K+ channels (BKCa) contribute to the whole-cell voltage- and time-dependent outward K+ current, as it was specifically inhibited by 5 mM 4-aminopyridine (4-AP; KDR blocker) (92 +/- 4% at 0 mV, n = 7), by 1 mM tetraethylammonium (TEA; BKCa blocker) (71 +/- 4% at +60 mV, n = 4), and by 200 nM iberiotoxin (BKCa blocker) (64 +/- 7% at +60 mV, n = 4). In outside-out patches, BKCa channels had a single-channel conductance of 132 +/- 4 pS (n = 24) in asymmetric K+ conditions and 216 +/- 4 pS (n = 4) in a symmetric K+ gradient. The activity of the BKCa channels was significantly augmented by 1 microM Ca2+ in the inside-out configuration. 4-AP had no effect on resting tone of intact arterial rings. TEA produced contraction of arterial rings whereas phloretin, an activator of BKCa, relaxed them, which means that BKCa channels are functional in intact tissue and are involved in the maintenance of resting tone in this human vessel. CONCLUSION: The identities of K+ channels in the human umbilical artery were shown using the patch-clamp technique, and the physiologic effect of K+ channels on resting tone was documented.
Assuntos
Canais de Potássio/análise , Artérias Umbilicais/química , 4-Aminopiridina/farmacologia , Cálcio/farmacologia , Condutividade Elétrica , Feminino , Humanos , Potenciais da Membrana , Músculo Liso Vascular/química , Técnicas de Patch-Clamp , Peptídeos/farmacologia , Bloqueadores dos Canais de Potássio/farmacologia , Canais de Potássio/fisiologia , Gravidez , Tetraetilamônio/farmacologiaRESUMO
OBJECTIVE: To investigate whether the steady decline in the maternal essential fatty acids (EFA) status during pregnancy observed in Dutch pregnant women is a local or general phenomenon. DESIGN: The EFA status was measured during uncomplicated, singleton pregnancy of healthy women from the Netherlands, Hungary, Finland, England and Ecuador. In addition, the EFA status of their neonates were measured at birth. Fatty acid profiles were analyzed in phospholipids isolated from maternal plasma and from umbilical plasma and cord vessel walls. RESULTS: Considerable differences between these centers were observed in the maternal EFA levels and EFA status indexes. However, the change in the absolute as well as relative amounts of the EFAs followed a similar course in the five populations during pregnancy. The neonatal EFA profiles reflected the differences found in maternal plasma during pregnancy and shortly after delivery. Comparable correlations were found, particularly, between the neonatal and the maternal n-3 fatty acids in the participating groups. CONCLUSIONS: It seems that the reduction in maternal EFA status during pregnancy is a general phenomenon, and is largely independent of differences in dietary habits and ethnic origin. Since the lowest values for certain maternal EFAs in a given country were significantly higher than the highest value of these EFAs throughout pregnancy in other countries, the functional implications of the pregnancy-associated reduction in the maternal EFA status for the fetal and neonatal development is not obvious and needs to be further elucidated.
Assuntos
Ácidos Graxos Essenciais/sangue , Recém-Nascido/sangue , Fosfolipídeos/sangue , Gravidez/sangue , Adulto , Análise de Variância , Equador , Inglaterra , Ácidos Graxos Essenciais/análise , Ácidos Graxos Ômega-3/análise , Ácidos Graxos Ômega-3/sangue , Feminino , Sangue Fetal/química , Finlândia , Idade Gestacional , Humanos , Hungria , Estudos Longitudinais , Países Baixos , Fosfolipídeos/análise , Análise de Regressão , Artérias Umbilicais/química , Veias Umbilicais/químicaRESUMO
To determine the influence of the prenatal long-chain polyunsaturated fatty acid (LCP) supply on prenatal growth and on postnatal LCP levels, we studied 52 preterm infants and assessed the relations between the LCP status at birth (reflecting the prenatal LCP supply), gestational age and prenatal growth, and the relation between the LCP status at birth and at 37 to 42 weeks of gestational age. After a correction for gestational age at birth, significant relations (p < or = 0.05) were observed between anthropometric measurements at birth (weight, head circumference, and length) and LCP levels in the umbilical artery wall, the LCP content of which reflects the long-term fetal LCP status. Independent of the neonatal diet (human milk or formula), LCP levels in erythrocyte phospholipids at term were positively related to levels in the umbilical artery wall (docosahexaenoic acid (22:6n-3): p < or = 0.0003; arachidonic acid (20:4n-6): p = 0.02). Postnatal diet significantly influenced LCP levels in plasma phospholipids at term (docosahexaenoic acid: p < or = 0.004; arachidonic acid: p = 0.02); formula-fed infants had lower values. We conclude that the LCP status of preterm infants at birth is related to prenatal growth. Moreover, next to the postnatal enteral diet, the LCP status at birth significantly affects LCP levels at term postconceptional age. This finding may warrant further studies of the effects of essential fatty acid-enriched maternal diets during pregnancy on the neonatal LCP status at birth.
Assuntos
Ácidos Graxos Insaturados/análise , Recém-Nascido Prematuro/crescimento & desenvolvimento , Recém-Nascido Prematuro/metabolismo , Antropometria , Ácidos Graxos Insaturados/sangue , Sangue Fetal/química , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro/sangue , Artérias Umbilicais/químicaRESUMO
En un grupo de 50 recién nacidos de término, con asfixia grave al nacer, definida por un pH de arteria umbilical igual o menor de 7.10, se evaluaron las complicaciones sistémicas agudas, los antecedentes perinatales y se correlacionó el pH de cordón con la calificación de Apgar. En 56 por ciento de los casos, no se detectó la asfixia antes del nacimiento; la causa más frecuente de ella fue el trabajo de parto o periodo expulsivo prolongado, seguida del desprendimiento prematuro de placenta. El riñón y el sistema nervioso central se afectaron en casi la mitad de los casos; un 24 por ciento de los neonatos tuvieron enfermedad pulmonar grave, un porcentaje similar tuvo afectación cardiovascular y 44 por ciento tuvo hipocalcemia. No hubo correlación entre calificación de Apgar y pH de cordón. La mortalidad fue de 22 por ciento y su causa principal fue la Hipertensión Pulmonar persistente