Ana Paula Brum Miranda Lopes

Dopplerfluxometria de artérias oftálmicas e avaliação da função endotelial nas formas precoce e tardia da pré-eclâmpsia

OBJETIVO: Avaliar possiveis diferencas entre a disfuncao endotelial, avaliada pela dilatacao fluxo-mediada, e hiperperfusao central, avaliada por dopplerfluxometria da arteria oftalmica, entre pacientes portadoras da forma precoce e tardia da pre-eclâmpsia. MATERIAIS E METODOS: O teste de dilatacao fluxo-mediada e a dopplerfluxometria da arteria oftalmica foram obtidos de 81 gestantes, sendo 56 portadoras de pre-eclâmpsia (26 na forma precoce e 30 na forma tardia) e 25 gestantes saudaveis (grupo controle). RESULTADOS: Portadoras de pre-eclâmpsia apresentaram valores menores de dilatacao fluxo-mediada quando comparadas ao grupo controle, tanto na forma precoce (7,62 ± 5,42% × 14,12 ± 6,14%; p = 0,02) como na forma tardia (5,83 ± 4,12% × 14,12 ± 6,14%; p = 0,00). Nao houve diferenca quando foram comparadas as duas formas (7,62 ± 5,42% × 5,83 ± 4,12%; p = 0,09). A dopplerfluxometria da arteria oftalmica apresentou-se significativamente menor nas pacientes portadoras de pre-eclâmpsia quando comparadas ao grupo controle, tanto na forma precoce (0,631 ± 0,024 × 0,737 ± 0,032; p = 0,01) como na forma tardia (0,653 ± 0,019 × 0,737 ± 0,032; p = 0,03). Nao houve diferenca entre as duas formas de apresentacao (0,631 ± 0,024 × 0,653 ± 0,019; p = 0,12). Os resultados basicamente demonstram reducao nos valores de dilatacao fluxo-mediada e dopplerfluxometria da arteria oftalmica nas formas tardia e precoce da pre-eclâmpsia quando comparadas ao grupo controle, sem, contudo, diferencas significativas entre as duas formas de apresentacao da doenca. CONCLUSAO: Os resultados indicam a presenca de disfuncao endotelial e hiperperfusao central em gestantes com pre-eclâmpsia, tanto na forma precoce como na tardia.

Predictive factors of perinatal mortality in transfused fetuses due to maternal alloimmunization: what really matters?

Introduction: Alloimmunization is the main cause of fetal anemia. There are not many consistent analyses associating antenatal parameters to perinatal mortality in transfused fetuses due to maternal alloimmunization. The study aimed to determine the prognostic variables related to perinatal death. Material and Methods: A cohort study analyzed 128 fetuses treated with intrauterine transfusion (IUT), until the early neonatal period. Perinatal mortality was associated with prognostic conditions related to prematurity, severity of fetal anemia and IUT procedure by univariated logistic regression. Multiple logistic regression was used to compute the odds ratio (OR) for adjusting the hemoglobin deficit at the last IUT, gestational age at birth, complications of IUT, antenatal corticosteroid and hydrops. Results: Perinatal mortality rate found in this study was 18.1%. The hemoglobin deficit at the last IUT (OR: 1.26, 95% CI: 1.04–1.53), gestational age at birth (OR: 0.53, 95% CI: 0.38–0.74) and the presence of transfusional complications (OR: 5.43, 95% CI: 142–20.76) were significant in predicting fetal death. Conclusion: Perinatal mortality prediction in transfused fetuses is not associated only to severity of anemia, but also to the risks of IUT and prematurity.

Transfusão Intra-uterina na Isoimunização Materna pelo Fator Rh

Purpose: to evaluate the intrauterine treatment of anemic fetuses that underwent intrauterine transfusions due to rhesus isoimmunization. Methods: the authors studied sixty-one fetuses undergoing intrauterine transfusions by the intravascular, intraperitoneal or both routes. The hydropic fetuses (19.7%) received only intravascular intrauterine transfusions. There was an overall number of 163 intrauterine transfusions with a mean of 2.7 procedures for each case. The indications for intrauterine transfusions were high values of bilirubin in amniotic fluid analyses by the Liley method or a hemoglobin concentration of cord blood below 10.0 g/mL. Results: the overall perinatal survival rate was 46% for hydropic fetuses and 84% for the nonhydropic ones. There were no maternal side effects related to the procedures. Half of the intrauterine transfusions were performed by the intravascular route. The mean gestational age at the delivery was 34.8 weeks. Conclusions: despite better perinatal results with intrauterine transfusions guided by ultrasound, especially using intravascular procedures, rhesus isoimmunization remains as an important cause of high rates of perinatal morbidity and mortality.

MammoSVD: A content-based image retrieval system using a reference database of mammographies

In this paper, we present a content-based image retrieval (CBIR) system called MammoSVD. This CBIR system is developed based on breast density — fatty or dense, and the database used, from the IRMA project, provides images with the ground truth already set. Singular value decomposition (SVD) is proposed for the breast density characterization by the selection of the first singular values, in order to represent texture along with the dimensionality reduction. Support-vector machine (SVM) is used to perform the retrieval operation. Considering the first 10% of the retrieved images, the precision rate is 90%, indicating the potential of the implemented CBIR system.

Isolamento, diferenciação e aspectos bioquímicos de células-tronco de líquido amniótico

The mesenchymals stem cells (MSCs) are cells with the great potential of differentiation are being introduced in the clinic for treatment of several diseases. Mesenchymal stem cells have several advantages including the stability of their phenotype in vitro. BACKGROUND: isolation of MSCs in amniotic fluid, its expansion and the demonstration of the capacity of these cells to differentiate in adipogenic and miogenic cells, without to change the chromosomal stability of the MSCs in culture. METHODS: in order to evaluate the functional change of these cells, were gotten values of the differentiated adipogenic cells and not differentiated through the dosage of triglycerides. The miogenic nature of the differentiated cells was analyzed comparing the creatine kinase - CK, lactic dehydrogenase - LDH and aldolase produced by the cells. RESULTS: the values of triglycerides were significantly higher in differentiated cells, showing intracitoplasmatic granule form after differentiation. All the biochemical characters were significantly higher in differentiated miogenic cells. CONCLUSIONS: this study suggests that the standardized protocol of differentiation can be used in the attainment of cells with characteristics of adipogenic and muscular cells, from amniotic fluid.

Avaliação de índices dopplerfluxométricos da veia cava inferior e do ducto venoso em fetos submetidos à transfusão intravascular

PURPOSE: to evaluate the effect of intravascular transfusion on ductus venosus and inferior vena cava Doppler ultrasound indexes (SV/CA) and to relate it to hemoglobin levels before transfusion. METHODS: this is a transversal prospective study. A total of 62 intravascular transfusions were performed in 27 fetuses from pregnancies with red blood cell isoimmunization. The 62 cases were divided into two groups: (1) fetuses with hemoglobin levels before transfusion £10 g/dL and (2) fetuses with hemoglobin levels before transfusion >10 g/dL. The SV/CA and CA/SV indexes were measured using color Doppler ultrasound 6 h before and 12 h after intravascular transfusion. The index values before and after transfusion in all 62 cases were compared. Thereafter we compared these indexes before and after transfusion regarding each group. The Wilcoxon test was used and the results were considered statiscally significant when p 10 g/dL (p=0.049), but the SV/CA index did not change in this group (p=0.086). CONCLUSION: venous Doppler study may be useful to understand fetal hemodynamic adjustment after intravascular transfusion. An increase in SV/CA without change in CA/SV after transfusion in anemic fetuses may be an important compensatory mechanism to increase intravascular volume. The increase in CA/SV index in fetuses with hemoglobin levels before transfusion <10 g/dL suggests a state of fetal hypervolemia.

Diagnóstico não invasivo da anemia fetal pela medida do pico de velocidade sistólica na dopplervelocimetria da artéria cerebral média

PURPOSE: to assess the correlation between middle cerebral artery peak systolic velocity and umbilical cord blood hemoglobin concentration and to determine its diagnostic value. PATIENTS AND METHODS: a cross-sectional prospective study was performed from January 2000 to May 2003. Forty-four isoimmunized pregnant women underwent a protocol for the identification of fetal hemolysis. When intrauterine transfusions were indicated, the umbilical cord blood hemoglobin concentration was measured at the beginning of the procedure. Each intrauterine transfusion preceded by Doppler velocimetry of the middle cerebral artery was regarded as one case, summing up eighty-three procedures. In all cases, the middle cerebral artery Doppler examinations were performed within the three hours preceding fetal blood sample collection. The systolic velocity peak was recorded and considered abnormal when its value was above 1.5 times the median for the corresponding gestational age. Hemocue® (B-Hemoglobin Photometer Hemocue AB; Angelholm, Sweden) was the device used to measure fetal hemoglobin concentration. The relationship between middle cerebral artery peak systolic velocity and cord blood hemoglobin was obtained by the c2 test, considered significant at p<0.05. RESULTS: in thirty-three cases the cord blood hemoglobin concentration was below 10.0 g/dL. There was a strong correlation between the two measured variables (p<0.001). The middle cerebral artery peak systolic velocity with values above 1.5 times the median was associated with cord blood hemoglobin concentration below 10 g/mL (p<0,001). The sensitivity of an increased middle cerebral artery peak systolic velocity was 75.8% for the detection of a cord blood hemoglobin level of 10 g/dL or lower. CONCLUSION: the middle cerebral artery peak systolic velocity can be used as a noninvasive method for the diagnosis of fetal anemia.

Tratamento das Uropatias Obstrutivas Fetais: Experiência com Novo Cateter

A abordagem das uropatias diagnosticadas no periodo pre-natal e controversa, principalmente, porque o prognostico desses fetos e variavel. Contudo, trabalhos pioneiros tem demonstrado que a drenagem pre-natal do trato urinario obstruido pode melhorar o resultado em fetos selecionados. O objetivo deste trabalho e relatar a experiencia do Servico no tratamento das lesoes obstrutivas do trato urinario, utilizando o cateter desenvolvido no Centro de Medicina Fetal do Hospital das Clinicas da UFMG. No total, 25/25 fetos com uropatia obstrutiva receberam o cateter. Tres fetos necessitaram de mais de uma insercao; 10 dos 25 fetos que receberam o cateter (40%) sobreviveram com boa funcao renal e pulmonar pos-natal. Ocorreram complicacoes em 12/25 casos (48%) incluindo 6 com drenagem inadequada ou migracao do cateter (24%); 1/25 (4%) ascite urinaria; 1/25 (4%) descolamento prematuro de placenta; 1/25 (4%) rutura prematura de membrana; 2/25 (08%) trabalho de parto prematuro; 01/25 (04%) fibrose ou cicatrizacao do parenquima renal. Tres dos 25 fetos (12%) morreram intra-utero e 12 (48%) fetos morreram no periodo neonatal. Concluindo, a drenagem do trato urinario com esse cateter provou ser tecnicamente possivel e segura para mae e feto, com uma taxa de sobrevida de 40%.