Pregnancy Outcomes in COVID-19: A Prospective Cohort Study in Singapore

INTRODUCTION@#Pregnant women are reported to be at increased risk of severe coronavirus disease 2019 (COVID-19) due to underlying immunosuppression during pregnancy. However, the clinical course of COVID-19 in pregnancy and risk of vertical and horizontal transmission remain relatively unknown. We aim to describe and evaluate outcomes in pregnant women with COVID-19 in Singapore.@*METHODS@#Prospective observational study of 16 pregnant patients admitted for COVID-19 to 4 tertiary hospitals in Singapore. Outcomes included severe disease, pregnancy loss, and vertical and horizontal transmission.@*RESULTS@#Of the 16 patients, 37.5%, 43.8% and 18.7% were infected in the first, second and third trimesters, respectively. Two gravidas aged ≥35 years (12.5%) developed severe pneumonia; one patient (body mass index 32.9kg/m2) required transfer to intensive care. The median duration of acute infection was 19 days; one patient remained reverse transcription polymerase chain reaction (RT-PCR) positive >11 weeks from diagnosis. There were no maternal mortalities. Five pregnancies produced term live-births while 2 spontaneous miscarriages occurred at 11 and 23 weeks. RT-PCR of breast milk and maternal and neonatal samples taken at birth were negative; placenta and cord histology showed non-specific inflammation; and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific immunoglobulins were elevated in paired maternal and umbilical cord blood (n=5).@*CONCLUSION@#The majority of COVID-19 infected pregnant women had mild disease and only 2 women with risk factors (obesity, older age) had severe infection; this represents a slightly higher incidence than observed in age-matched non-pregnant women. Among the women who delivered, there was no definitive evidence of mother-to-child transmission via breast milk or placenta.

Serosurveillance for vaccine-preventable diseases: A look inside the pertussis experience / Serovigilancia de enfermedades prevenibles por vacunación: una mirada desde la experiencia con la tosferina

Abstract Introduction: Serological surveillance (serosurveillance) provides the most direct measure of herd immunity of vaccine-preventable diseases. Little is known about the opportunities and challenges of serosurveillance experiences, particularly pertussis. Objective: To describe the process of serosurveillance for vaccine-preventable diseases with an emphasis on the experience of pertussis in the metropolitan area of Antioquia (Valle de Aburrá) in 2015 and 2016 and analyze the contributions and challenges for its sustainability. Materials and methods: We described the planning and conduction of serosurveillance of pertussis antibodies of mothers and in the umbilical cord at the time of delivery in eight hospitals based on random sampling and their capacity to advance the serosurveillance periodically. We compared the contributions and the challenges of this experience with other probabilistic and non-probabilistic programs. Results: We achieved the participation of hospitals and mothers respecting the delivery care process. We established a serum bank following ethical and technical guidelines. This program based on the random selection of hospitals and mothers has enabled the estimation of antibodies prevalence in mothers and in the umbilical cord, which has been possible given the high coverage of hospital care during childbirth at a lower cost and fewer risks than a population-based survey in conflictive areas. The main challenges for the sustainability of this program are the creation of stable jobs and access to funding and legal and methodological long-term frameworks. Conclusions: Hospital serosurveillance as described is an option to monitor the impact of vaccination on the population. Our experience could be reproduced in other regions under similar conditions if the above-mentioned challenges are solved.

Resumen Introducción. La vigilancia serológica es la forma más directa de medir la inmunidad de rebaño frente a las enfermedades prevenibles por vacunación. Poco se sabe acerca de las oportunidades y los desafíos de las experiencias de serovigilancia, en general y, específicamente, la de la tosferina. Objetivo. Describir el proceso de serovigilancia de enfermedades prevenibles por vacunación con énfasis en la experiencia en el caso de la tosferina en el área metropolitana de Antioquia (Valle de Aburrá) en el 2015 y el 2016 y analizar lo que dicha experiencia ha aportado y los desafíos que persisten para su sostenibilidad. Materiales y métodos. Se describió el proceso de planeación y el desarrollo de la serovigilancia de tosferina en el momento del parto en ocho hospitales seleccionados al azar, así como la capacidad para adelantar el programa de manera periódica. Se compararon los aportes y los desafíos en el curso de esta experiencia con los de otros programas poblacionales probabilistas e institucionales no probabilistas. Resultados. Se logró la participación de los hospitales y de las madres con pleno respeto del proceso de atención del parto, y se conformó un banco de sueros siguiendo lineamientos éticos y técnicos. El programa permitió estimar la prevalencia de anticuerpos en la madre y en el cordón umbilical, lo que se facilitó por la alta cobertura de atención hospitalaria del parto, a un menor costo y menos riesgos que los programas poblacionales en zonas conflictivas. Los principales desafíos para la sostenibilidad del programa son la estabilidad laboral del personal de salud, así como normas y una financiación de largo plazo. Conclusiones. La serovigilancia hospitalaria es una opción para monitorizar el impacto poblacional de la vacunación. Esta experiencia se podría extender a otras regiones en condiciones similares si se resuelven los retos mencionados.

Placental and colostral transfer of antibodies reactive with enteropathogenic Escherichia coli intimins α, ß, or γ / Transferência placentária e colostral de anticorpos reativos a Escherichia coli enteropatogênica com expressão das intiminas α, ß, or γ

Abstract Objective: Intimins are protein adhesins of enteropathogenic Escherichia coli and enterohemorrhagic E. coli capable of inducing attachment and effacement lesions in enterocytes. Anti-intimin antibodies are important for the protection from enteropathogenic E. coli and enterohemorrhagic E. coli infections because these antibodies inhibit bacterial adhesion and impair the initial step of the pathogenesis. We studied the transfer of maternal anti-intimin antibodies from healthy Brazilian mothers to their newborns through the placenta and colostrum. Methods: Serum immunoglobulin G and secretory immunoglobulin A antibodies against conserved and variable regions of intimins α, β, and γ were analyzed using an enzyme linked-immunosorbent assay in the blood and colostrum from 45 healthy women as well as cord blood serum samples from their newborns. Results: The concentrations of antibodies reactive with α intimin were significantly lower than those of anti-γ and anti-conserved intimin antibodies in the colostrum samples. IgG serum antibodies reactive with all the subtypes of intimins were transferred to the newborns, but the concentrations of anti-conserved intimin serum antibodies were significantly higher in mothers and newborns than concentrations of antibodies against variable regions. The patterns of IgG transfer from mothers to newborns were similar for all anti-intimin antibodies. These values are similar to the percentage transference of total IgG. Conclusions: Anti-intimin antibodies are transferred from mothers to newborns through the placenta, and reinforce the protection provided by breastfeeding against diarrheagenic E. coli infections.

Resumo Objetivo: As intiminas são adesinas proteicas de Escherichia coli enteropatogênicas (EPEC) e enterro-hemorrágicas (EHEC) capazes de induzir as lesões attaching and effacing nos enterócitos. Anticorpos anti-intiminas são importantes para a proteção contra infecções por EPEC e EHEC porque esses anticorpos inibem a adesão bacteriana e impedem o passo inicial do mecanismo patogênico dessas bactérias. Nós estudamos a transferência de anticorpos maternos anti-intiminas de mães brasileiras saudáveis para os seus recém-nascidos através da placenta e do colostro. Métodos: Anticorpos séricos da classe IgG e secretórios da classe IgA (SIgA) reativos com as porções conservada (cons) e variáveis das intiminas α (vα), β (vβ) e γ (vγ) foram analisados pelo teste de ELISA no sangue e no colostro de 45 parturientes saudáveis e no sangue de cordão umbilical dos seus respectivos recém-nascidos. Resultados: As concentrações de anticorpos reativos com intimina vα foram significativamente mais baixas que as dos anticorpos anti-vγ e anti-cons nas amostras de colostro. Anticorpos IgG séricos reativos com todas as intiminas foram transferidos para os recém-nascidos, mas as concentrações de anti-cons foram significativamente mais altas tanto nas mães como nos recém-nascidos do que os anticorpos reativos com as regiões variáveis das intiminas. O padrão de transferência de IgG das mães para os recém-nascidos foi muito semelhante para todos os anticorpos anti-intiminas. Os valores de porcentagem de transferência foram semelhantes à transferência de IgG total. Conclusões: Anticorpos anti-intimina são transferidos das mães para os recém-nascidos pela placenta e corroboram a proteção contra infecções por Escherichia coli diarreiogênicas (DEC) conferida pelo aleitamento materno.

Índice de massa corporal, circunferência da cintura e hipertensão arterial em estudantes / Índice de masa corporal, circunferencia de la cintura y hipertensión arterial en estudiantes / Body mass index, waist circumference, and arterial hypertension in students

RESUMO Objetivo: investigar qual o melhor preditor antropométrico de hipertensão arterial em alunos de escolas privadas. Método: estudo transversal, com amostra composta por 286 alunos com idade de 10 a 14 anos de duas escolas privadas de Paranavaí-Paraná. As variáveis analisadas foram: índice de massa corporal, circunferência de cintura e pressão arterial. Na análise estatística foram utilizados os testes de correlação parcial de Pearson e a regressão logística multivariada, considerando-se p<0,05. Resultados: os dois indicadores antropométricos demonstraram fracas correlações com os níveis sistólicos e diastólicos, com coeficientes (r) variando de 0,27 à 0,36 (p< 0,001). Na análise multivariada, o único indicador antropométrico associado ao risco de hipertensão arterial foi a circunferência de cintura (OR= 2,3; IC 95%: 1,1-4,5) independente da idade e gênero. Conclusão: nesta faixa etária, a circunferência de cintura parece ser melhor do que índice de massa corporal como preditor de hipertensão arterial. .

RESUMEN Objetivo: investigar cuál es el mejor predictor antropométrico de la hipertensión arterial en los alumnos de escuelas particulares. Métodos: estudio transversal con muestra compuestas por 286 alumnos con edad de 10 a 14 años de dos escuelas privadas de Paranavaí-Paraná. Las variables analizadas fueron: índice de masa corporal, circunferencia de la cintura y la presión arterial sistólica y diastólica. En el análisis de estadísticas fueron utilizadas las pruebas de correlación parcial de pearson y regresión logística multivariada considerándose p<0.05. Resultados: los dos indicadores antropométricos han mostrado débiles correlaciones con los niveles sistólicos y diastólicos, con Coeficientes (r) variando de 0,27 a 0,36 (p<0,001). En el análisis multivariado el único indicador antropométrico asociado al riesgo de hipertensión arterial fue la circunferencia de la cintura (OR=2,3; IC 95%: 1,1- 4,5) independiente de la edad y el género. Conclusión: en este grupo de edad, la circunferencia de la cintura parece ser mejor de que el índice de masa corporal como predictor de la hipertensión arterial. .

ABSTRACT Objective: to investigate what is the best anthropometric predictor of arterial hypertension among private school students. Method: this was a cross-sectional study with 286 students between the ages of 10 and 14 from two private schools in the city of Paranavaí, Paraná, Brazil. The following variables were analyzed: body mass index, waist circumference and blood pressure. Statistical analysis was conducted with Pearson’s partial correlation test and multivariate logistic regression, with p<0.05. Results: both anthropometric indicators displayed weak correlation with systolic and diastolic levels, with coeffi cients (r) ranging from 0.27 to 0.36 (p < 0.001). Multivariate analysis showed that the only anthropometric indicator associated with arterial hypertension was waist circumference (OR= 2.3; 95% CI: 1.1-4.5), regardless of age or gender. Conclusion: this age group, waist circumference appeared to be a better predictor for arterial hypertension than body mass index. .

The Difference of Lymphocyte Subsets Including Regulatory T-Cells in Umbilical Cord Blood between AGA Neonates and SGA Neonates

PURPOSE: This study aimed to compare the regulatory T cells in cord blood of appropriate for gestational age (AGA) neonates with those of small for gestational age (SGA) neonates. MATERIALS AND METHODS: Umbilical cord blood was collected upon labor in 108 healthy full-term (between 37 and 41 gestational weeks) neonates, who were born between November 2010 and April 2012. Among them, 77 samples were obtained from AGA neonates, and 31 samples were obtained from SGA neonates. Regulatory T cells and lymphocyte subsets were determined using a flow cytometer. Student's t-test for independent samples was used to compare differences between AGA and SGA neonates. RESULTS: Regulatory T cells in cord blood were increased in the SGA group compared with normal controls (p=0.041). However, cytotoxic T cells in cord blood were significantly decreased in the SGA group compared with normal controls (p=0.007). CONCLUSION: This is the first study to compare the distribution of lymphocyte subsets including regulatory T cells in cord blood between AGA neonates and SGA neonates.

Avaliação imunofenotípica de subpopulações linfocitárias no sangue do cordão umbilical e periférico de suínos neonatos (Sus scrofa) / Imunophenotyping avaliation of lymphocyte subsets in cord blood and peripheral blood of newborn piglets (Sus scrofa)

Considerando a importância do uso do sangue do cordão umbilical como fonte potencial de células tronco hematopoiéticas e o uso do suíno doméstico (Sus scrofa) como modelo para pesquisas biomédicas em medicina regenerativa, e por outro lado, visando dar um contributo sobre a quantificação das subpopulações linfocitárias no sangue do cordão umbilical e periférico, objetivou-se quantificar as células CD4+, CD5+ e CD8+ nas amostras de sangue de suínos neonatos. Analisaram-se as amostras do sangue do cordão umbilical e periférico de 48 leitões de linhagem Topigs, provenientes de porcas hígidas, inseminadas artificialmente e de parto natural. Foram coletadas amostras de sangue do cordão umbilical e periférico no momento do nascimento, por meio de venopunção da veia umbilical e seio venoso retro-oftálmico, respectivamente. As quantificações imunofenotípicas de células CD4+, CD5+ e CD8+ foram obtidas por citometria de fluxo. Os valores médios obtidos para as contagens das células CD4+, CD5+ e CD8+ do sangue do cordão umbilical e periférico apresentaram-se inferiores aos reportados para o sangue periférico de suínos adultos, sugerindo um componente imunológico imaturo. A proporção CD4+: CD8+ obtida no sangue do cordão umbilical (3,2±1,2 por cento) e no sangue periférico (3,2±1,7 por cento) ilustrou a predominância dos linfócitos TCD4+ com relação aos TCD8+. A quantidade relativa de células CD4+ e CD8+ no sangue do cordão umbilical e periférico foi de 1,37±0,86 por cento e 1,15±0,57 por cento, respectivamente.

Considering the importance of umbilical cord blood as a potential source of stem cell and, on the other hand, the use of the domestic swine (Sus scrofa) as a useful model for biomedical research in regenerative medicine and aiming to contribute about the quantification of lymphocyte subsets in umbilical cord blood and peripheral blood of newborn piglets, this study aimed to quantify CD4+, CD5+ and CD8+ cells from umbilical cord blood and peripheral blood from pigs at term blood samples. Were analyzed samples of the umbilical cord blood and peripheral of 48 piglets of Topigs lineage, from healthy mothers, artificially inseminated and natural birth. Blood samples were collected from the umbilical cord at birth, by the umbilical vein, and peripheral blood by venous sinus retro-ophthalmic. The immunological measurements of CD4+, CD5+ and CD8+ were obtained by flow cytometry. The relative average values for the CD4+, CD5+ e CD8+ counts in umbilical cord blood and peripheral blood of newborn piglets were inferior to those reported for peripheral blood in adult pigs, suggesting immunological immaturity. The ratio CD4+:CD8+ in umbilical cord blood (3.2±1.2 percent) and peripheral blood (3.2±1.7 percent) showed a predominance of TCD4+ over TCD8+. The percentage of CD4+ and CD8+ cells was 1.37±0.86 percent and 1.15±0.57 percent, respectively, in umbilical cord blood and peripheral blood.

Genotipagem RhD fetal não invasiva no acompanhamento de gestantes RhD negativo / Non invasive Fetal RHD Genotyping in management of pregnant RhD negative women

O acompanhamento de gestantes de fenótipo RhD negativo é baseado na premissa de que seus fetos podem estar em risco de desenvolver a doença hemolítica perinatal (DHPN) ou eritroblastose fetal, trazendo sérios riscos ao feto em decorrência de hemólise, com consequente anemia, hidropsia e, por vezes, óbito intrauterino. Procedimentos invasivos como amniocentese ou cordocentese podem ser utilizados para se inferir o fenótipo RhD fetal, entretanto, oferecem riscos ao feto e à gestante. Nos últimos anos, o conhecimento sobre a genética dos grupos sanguíneos e o desenvolvimento de técnicas de biologia molecular tem permitido a inferência de fenótipos de grupos sanguíneos a partir da detecção do material genômico. Inicialmente, a genotipagem do DNA fetal para o gene RhD era feita a partir de amostras de amniócitos ou de vilosidades coriônicas. No entanto, por tratar-se de testes invasivos, traziam risco ao feto e à gestante. A possibilidade de se obter DNA fetal a partir do plasma materno foi um grande avanço na prática clínica, por ser um procedimento não invasivo e, portanto, isento de risco. Esta revisão apresenta os princípios da técnica e os resultados de diferentes protocolos para genotipagem RhD fetal (publicados ao longo dos anos) e qual o seu propósito no acompanhamento das gestantes RhD negativo

The RhD negative pregnant women management has been based on the fact that their fetuses may be at risk of developing hemolytic diseases (DHPN) or erythroblastosis fetalis. This condition may bring serious risks to the fetus due to hemolysis, with consequent anemia and hydrops and sometimes, intrauterine death. Invasive procedures such as amniocentesis or cordocentesis may be performed to assess the fetal RhD phenotype, however, it offers risks to both fetus and pregnant woman. In recent years, the knowledge about the genetics of blood groups and the development of molecular biology techniques has allowed the inference of blood group phenotypes by the detection of genomic material. Initially, the fetal DNA genotyping for the RHD gene was performed from amniocytes or chorionic villi samples. Unfortunately, these invasive tests could bring risk to the fetus and the pregnant woman. However, the possibility of obtaining fetal DNA from maternal plasma has been a major advance in clinical practice, as being a non-invasive procedure and therefore not providing any risks. This review presents the principles of techniques and results of different protocols for fetal RHD genotyping (published over the years) and its goal on the management of RhD negative pregnant women

IgG and IgM western blot assay for diagnosis of congenital toxoplasmosis

The aim of this study was to evaluate the utility of western blot (WB) analysis as a diagnostic tool for congenital toxoplasmosis in 215 newborn infants. The children were submitted to clinical examinations to assess macular, neurological and hearing signals. The WB results obtained were compared to the persistence of IgG antibodies at the end of 12 months, which is regarded as the "gold standard" diagnosis of congenital toxoplasmosis. Association between the WB results and the clinical signs presented by the infants was also assessed. Of the 215 children, 177 had a confirmed congenital toxoplasmosis diagnosis and 38 were uninfected. IgG-WB showed a sensitivity of 73.5 percent and a specificity of 97.4 percent. IgM-WB showed a sensitivity of 54.8 percent and a specificity of 94.7 percent. The IgG-WB and IgM-WB combination increased the sensitivity to 86.5 percent. The IgM-WB-positive children had a 1.4-fold greater risk of presenting active macular lesions than did those that were IgM-WB-negative. This study showed that the WB assay is a useful tool to confirm a diagnosis of congenital toxoplasmosis and that the IgM-WB-positive results can indicate active macular lesions in newborn infants.

Congenital rubella syndrome after rubella vaccination in 1-4 weeks periconceptional period.

OBJECTIVE: To examine weather exposure to rubella vaccine during 1-4 wk periconceptional period can cause congenital rubella syndrome (CRS). METHODS: This prospective study was performed in 60 pregnant women who received rubella vaccine inadvertently 1-4 wk pre or post conception. Time of conception was determined by last menstrual period (LMP) and first trimester sonography. In addition to gathering mother's obstetric and demographic information, all neonates were evaluated for CRS signs by systemic physical examination and anti rubella IgG and IgM antibody titers in cord blood samples. RESULTS: A total of 60 pregnant women with the median gestational age of 38 weeks were studied. The mean maternal age was 22 years and 58.3% of pregnancies were unintended. In 90% of mothers there were no post vaccination side effects (fever, lymphadenopathy, arthritis, arthralgia). None of the mothers had a history of drug abuse, smoking or teratogenic exposures. Mean neonatal weight was 3100grs and 6.7% of them were premature. No signs of CRS were found in the neonates based on systemic physical exam at birth and one month later. Mean value of cord blood anti rubella IgG titere was 148/28+/-67/26 lu/ml. cord blood anti rubella IgM was negative in all of the neonates. CONCLUSION: In this study inadvertent rubella vaccination 1-4 wk before and after conception did not cause CRS in neonates and according to all reasearches pregnancy termination is not indicated in these cases.

Pesquisa de sífilis congénita al momento del parto: ¿Suero materno o sangre de cordón? / Diagnosis of congenital syphilis at delivery: Maternal serum or cord blood?

La sífilis congénita (SC) es un problema importante en Chile, con una tasa de 0,25/1.000 recién nacidos (RNs) vivos en el año 2004. En el año 2000, el Ministerio de Salud recomendaba como tamizaje al momento del parto una muestra de sangre de cordón. El Centro de Control y Prevención de Enfermedades, (CDC), Atlanta, E.U.A. recomendó, desde 1998, el tamizaje al parto con suero materno ya que respecto del suero del RN, la sangre de cordón y el suero materno tienen respectivamente hasta 5 y 0,5 por ciento> de falsos negativos. Objetivo: Determinar el mejor tamizaje al momento del parto. Métodos: Se estudiaron muestras de suero materno y sangre de cordón de los RNs durante un año. Se realizó RPR y de ser positiva, pruebas treponémicas confirmatorias (imunocromatográfico Determine®, ELISA Captia® IgG e IgM y microhemaglutinación). Todos los pacientes confirmados fueron vistos por el especialista para definir los casos de SC. Resultados: Entre junio de 1999 y agosto del 2000 se estudiaron 2.741 binomios madre-RN; de éstos 37/2.704 (1,3 por ciento) fueron RPR reactivos. Once eran RPR reactivo en la madre y en el RN (Grupo I), 9 eran RPR reactivo en el RN y no reactivo en la madre (Grupo II) y 17 eran RN con RPR no reactivo y reactivo en la madre (Grupo III). En el Grupo I hubo 64 por ciento> (7/11) de verdaderos (+)s y 36 por ciento (4/11) de falsos (+)s del RPR. En el Grupo II, 9/ 9 (100 por cientoo), correspondieron a falsos (+)s del RPR en sangre de cordón y en el Grupo III, 11/17 (67 por ciento>) correspondieron a falsos (+)s del RPR en sangre materna pero hubo 6/17 (35 por ciento>) que correspondían a sífilis durante el embarazo y en tres de ellas no hubo tratamiento intra-embarazo, por lo que fueron catalogadas como SC y los RNs debieron ser tratados. En total hubo 9 RNs que correspondieron a SC (6 del grupo I y 3 del grupo III). Si sólo se hubiese realizado tamizaje en sangre de cordón, 3 RNs con SC no se hubiesen....

Congenital syphilis (CS) is an important health problem in Chile, with a rate of 0.25/1,000 live newborn (NB) during year 2004. In 2000, the Chilean Ministry of Public Health recommended to perform a screening in cord blood at the moment of delivery. Instead, the Centers for Disease Control and Prevention guidelines recommend the screening in maternal serum since cord blood has up to 5 percent of false (-) versus 0.5 percent of maternal serum, both with respect to the NB serum. Objective: Maternal serum and NB cord blood were studied during one year to determine the best screening method at delivery. Methods: RPR was performed and positive results were confirmed by treponemic test (immunochromatographyDetermine®, ELISA Captia®, Ig and IgM, and MHA-Tp). Serologically confirmed patients were evaluated by the specialist to define CS cases. Results: Between June 1999 and August 2000 2,741 binomies were studied; of these, 37 (1.3 percent) were RPR reactive and 2.704 were non-reactive. In 11 of the 37 reactive cases, mother and NB were RPR reactive (Group I), in 9 cases the NB was RPR reactive and the mother was non-reactive (Group II), and the other 17 were NB non-reactive and mother reactive (Group III). In group I, 7/11 (64 percent) were true (+)s and 4/11(36 percent)) false (+)s of RPR. In group II, 9/9 (100 percent) corresponded to false (+)s of RPR in cord blood, and in group III, 11/17 (65 percent) corresponded to false (+)s of RPR in maternal blood but 6/17 (35 percent) were found to be cases of syphilis during pregnancy. Three of them were not treated opportunely and were designed as CS. In total 9 NB corresponded to CS (6 in group I and 3 in group III). If the screening had been performed only in cord blood, three NB with CS would have not been diagnosed. Conclusion: Even when maternal serum has a high rate of false (+)s, it has better sensitivity than cord blood for the diagnosis of CS, thus it is suggested to perform the screening ...

Artículos de revisión: cultivos de expansión ex vivo de células madre a partir de sangre de cordón umbilical / Reviews: hematopoietic stem cell, ex vivo expansion from umbilical cordon blood

El éxito en el enfrentamiento a las hemopatías malignas depende de la erradicación de los clones tumorales por medio de la quimioterapia y la radioterapia. Sin embargo, en determinados pacientes la capacidad de curación se muestra limitada, y se requiere la sustitución de la función medular dañada por una nueva hematopoyesis sana, a través del trasplante de médula ósea (TMO). Este tipo de terapia celular puede contar ahora con donantes alternativos obtenidos a partir de la sangre de cordón umbilical (SCU) almacenada en bancos creados en varios países. Se ha comprobado la necesidad de promover un implante más rápido que disminuya la morbimortalidad relacionada con el procedimiento y permita la generalización de su uso, y se han propuesto estrategias basadas en la expansión de las células progenitoras hematopoyéticos (CPH) ex vivo, en cultivos a partir de SCU, lo que permite su uso en trasplantes con bajo contenido celular, y para diferenciar células pertenecientes a diferentes linajes hematopoyéticos, e incluso tejidos, con diferentes objetivos: trasplante hematopoyético, soporte de la recuperación a corto plazo, inmunoterapia, terapia génica, y diferenciación a tejidos mesenquimales. En esta revisión se explica cómo, de un producto habitualmente desechado, la SCU se ha convertido en una fuente de gran interés científico por la facilidad de su colecta, la fuente "ilimitada" de donantes, la calidad biológica de sus células madre cercanas a la época embrionaria y fetal del desarrollo, y la posibilidad de un uso amplio en diferentes estrategias de expansión ex vivo para terapia celular.

Congenital toxoplasmosis in two health institutions in Trinidad / Toxoplasmosis congénita en dos centros de salud de Trinidad

Toxoplasmosis is the most widespread zoonosis and an important human disease particularly in children where it could cause visual and neurological impairment and mental retardation. This study was conducted to determine the prevalence of toxoplasmosis, especially congenital toxoplasmosis in patients at two health institutions in Trinidad A total of 504 cord blood samples of newborn babies were collected: 174 from a women's hospital and 330 from a general hospital. In order to elicit aternal and prenatal risk factors for toxoplasmosis, mothers of the newborns completed a questionnaire. Enzyme-immuno assay (EIA) was used to detect IgG and IgM to Toxoplasma gondii. Overall, of 504 serum samples tested, 220 (43.7%) were seropositive for IgG while the prevalence of congenital toxoplasmosis as reflected by IgM was 0.4%. The prevalence of IgG and IgM by health institutions was not significantly different (p > 0.05; chi-square). The prevalence of toxoplasmosis using IgG was highest in neonates of mothers who were of East Indian descent (54.1%), had four children (52.9%), kept cats in households (47.7%), practised outdoor gardening (50.8%), consumed raw meat (66.7%), had experienced miscarriage(s) (47.3%), stillbirths (66.7%), or who had eye problem(s) (52.9%) and mental retardation (50.0%). The study prevalence of congenital toxoplasmosis revealed a high seroprevalence oftoxoplasmosis in neonates but there was 0.4% serological evidence of congenital disease. It indicates a need for sensitization of the population and healthcare workers and for follow-up of infected children for clinical evidence of the disease. This would be necessary to fully appreciate the impact of toxoplasmosis in Trinidad and Tobago. The differences from comparison groups were however not statistically significant (p > 0.05; chi-square).

La toxoplasmosis es la zoonosis más extendida y una enfermedad humana importante, particularmente en niños, a quienes puede causar daño visual y neurológico, y retraso mental. Este estudio se llevó a cabo con el propósito de determinar la prevalencia de la toxoplasmosis, especialmente la toxoplasmosis congénita en pacientes de dos centros de salud en Trinidad. Se recogieron un total de 504 muestras de sangre de cordón umbilical de neonatos: 174 de mujeres en un hospital de mujeres y 330 en un hospital general. A fin de obtener información sobre los factores de riesgo maternos y prenatales en relación con la toxoplasmosis, las madres de los recién nacidos llenaron una encuesta. Un ensayo inmunoenzimático (EIE) fue usado para detectar anticuerpos IgG e IgM contra el Toxoplasma gondii. En general, de 504 muestras de suero examinadas, 220 (43.7%) resultaron seropositivas al IgG, mientras que la prevalencia de la toxoplasmosis congénita reflejada por el IgM fue 0.4%. La prevalencia de IgG e IgM por parte de las instituciones de salud no fue significativamente diferente (p > 0.05; chi-cuadrado). La prevalencia de la toxoplasmosis usando IgG fue más alta en los neonatos cuyas madres eran ascendencia indoriental (54.1%), tenían cuatro niños (52.9%), mantenían gatos en sus casas (47.7%), practicaban jardinería al aire libre (50.8%), consumían carne cruda (66.7%), habían tenido aborto(s) (47.3%), partos de feto muerto (66.7%), o tenían problema(s) de los ojos (52.9%) y retardo mental (50.0%). Este estudio de la toxoplasmosis congénita, reveló una alta seroprevalencia de toxoplasmosis en neonatos, pero hubo 0.4% de evidencia serológica de enfermedad congénita. Esto apunta a la necesidad de sensibilizar a la población y a los trabajadores del cuidado de la salud, e igualmente indica la necesidad de realizar seguimientos a los niños infectados, en busca de evidencia clínica de la enfermedad. Esto es necesario si se quiera valorar totalmente el impacto de la...

Fetal rhd genotyping from maternal plasma in a population with a highly diverse ethnic background

OBJETIVO: Avaliar o desempenho da reação em cadeia da polimerase (PCR) em gel (convencional) como método diagnóstico não-invasivo para a genotipagem RHD fetal, por meio da análise do plasma materno. MÉTODOS: Foi conduzido um estudo de validação de teste diagnóstico a partir de 81 amostras sangüíneas obtidas de gestantes brasileiras RhD-negativo, entre 4 e 41 semanas de gestação. As regiões exon 10 e intron 4 do gene RHD foram testadas por meio da reação em cadeia da polimerase alelo-específica (AS-PCR) convencional. Os resultados da genotipagem fetal foram comparados com a tipagem sangüínea convencional no período neonatal. RESULTADOS: Quinze amostras foram obtidas no primeiro trimestre, 37 no segundo trimestre e 29 no terceiro trimestre. Houve falha de amplificação em 6 amostras. A concordância entre os resultados da genotipagem e da tipagem neonatal foi de 97,3%, sensibilidade de 98,3% e especificidade de 93,8%.CONCLUSÃO: AS-PCR convencional é um método com bom desempenho para a genotipagem RHD fetal por meio da análise do plasma materno, mesmo em uma população com alto grau de miscigenação.

Doença celíaca em crianças e adolescentes com síndrome de Down / Celiac disease in children and adolescents with Down syndrome

OBJETIVOS: Alta prevalência de doença celíaca em pacientes com síndrome de Down tem sido descrita em vários países. No entanto, no Brasil ainda não há relatos mostrando essa associação. O presente estudo teve como objetivo avaliar a prevalência de doença celíaca em crianças e adolescentes com síndrome de Down no sul do Brasil. MÉTODOS: Setenta e um pacientes (32 do sexo feminino e 39 masculino, 2-18 anos) provenientes de Curitiba, Brasil, foram estudados. Oitenta indivíduos (42 do sexo masculino e 38 feminino, 2-19 anos) foram utilizados como controles do estudo. Todas as amostras foram investigadas para anticorpo anti-endomísio (EmA) e anti-transglutaminase tecidual (anti-tTG). O EmA foi pesquisado através de imunofluorescência indireta usando cordão umbilical como substrato e o anti-tTG através da técnica de ELISA, utilizando transglutaminase tecidual como antígeno. As dosagens de IgA foram realizadas por turbidimetria. RESULTADOS: Cinco pacientes com síndrome de Down (7 por cento) foram positivos para EmA-IgA, com títulos entre 1/5 e 1/80 e catorze (17,5 por cento) para anti-tTG (21-340 unidades). Todos os pacientes positivos para EmA apresentaram simultaneamente positividade para o anti-tTG. Os achados clínicos e histológicos na mucosa intestinal confirmaram doença celíaca em quatro pacientes. O outro paciente EmA positivo não foi submetido a biópsia duodenal. Os pacientes positivos apenas para anti-tTG apresentaram valores limítrofes (< 25 unidades) e eram assintomáticos. Nenhum indivíduo do grupo controle foi positivo para EmA ou anti-tTG. Nenhuma amostra do estudo foi deficiente para IgA. CONCLUSÕES: Os dados do presente estudo mostram alta prevalência (5,6 por cento) de doença celíaca confirmada em crianças e adolescentes com síndrome de Down da região sul do Brasil.

Respuesta inmune en neonatos no infectados nacidos de madres infectadas por Trypanosoma cruzi / Immune responses of non-infected neonates of mothers infected with Trypanosoma cruzi

We have investigated if maternal T. cruzi infection could induce in utero innate and/or adaptive immune responses in uninfected neonates by measuring specific IgM and IgA antibodies in cord blood plasma, and by performing phenotypic and functional studies of umbilical cord blood cells of their newborns (M+B- group). We detected T. cruzi-specific IgM and IgA antibodies in M+B- cord blood, indicating they had mounted in utero a strong B cell response, although they are not infected. On the other hand, circulating T cells of such uninfected neonates displayed a low level of activation, as seen bya slightly increased expression of the activation markers CD45RO on CD4+ T cells and HLA-DR on CD8+ T cells, although the proportion of CD4+ and CD8+ T cells was unmodified as compared to newborns from uninfected mothers (MB- group). This activation did not give rise to a proliferative response upon stimulation by T. cruzi antigens in vitro. However, M+B- cells produced low levels of lymphokines (IFN-gamma and IL-13) upon mitogenic stimulation, which was not the case of M-B- newborn cells. Beside this, M+B- blood cells produced higher levels of inflammatory cytokines (IL-1b, IL-6, TNF-alpha) than M-B- cells when stimulated with the T. cruzi lysate or LPS, suggesting the over-activation of the innate response in M+B- newborns. Monocytes participated in such inflammatory response since M+B- purified cord blood monocytes produced higher levels of TNF- when incubated with LPS or a T. cruzi lysate than M-B- cells. Altogether, these results show that, even in the absence of congenital infection, maternal T. cruzi infection triggers in utero both adaptive and innate immune responses in their babies. This indicates that parasite circulating antigens have been transferred from mothers to their fetuses.

Los fectos humanos estan capaces de generar una respuesta inmune T CD8 similar a la de los adultos / The human fetuses are be able to develep an adult-like immune CD8 T-cell response

Fetal/Neonatal immune responses are generally considered to be immature and weaker than in adults. We have sudied the cord blood T-cells of newborns congenitally-infected whith Tripanosoma cruzi, the protozoan agent of Chagas' disease. Our data demonstrate a predominant activation of CD8 T-cells expressing activation markers and armed to mediate effector functions. Indeed, we have detected parasite-specific CD8 T-cells secreting interferon-ã. Such response is enchanced in the presence of rIL-15. These findings point out that the fetal immune system is more competent than previously appreciated, since fetuses exposed to live pathogens are able to develop an adult-like immune CD8 T-cell response.

Experiencia del uso del doppler de arteria cerebral media fetal en el manejo de madres con enfermedad hemolítica sensibilizadas / Experience in the use of doppler for fetal middle artery in the management of sensitized mothers with hemolytic disease

La enfermedad hemolítica perinatal se caracteriza por la aparición de anticuerpos contra la membrana del glóbulo rojo fetal lo que lleva a anemia fetal. La medición con Doppler del peak sistólico de la arteria cerebral media (ACM) se correlaciona directamente con el grado de anemia fetal y por lo tanto con la gravedad de la enfermedad hemolítica. Se realizó un seguimiento de 20 pacientes Rh (-) sensibilizadas, atendidas en el Servicio de Ginecología del Hospital San Juan de Dios con mediciones seriadas del peak sistólico de la ACM. El 100 por ciento de los valores observados para el peak sistólico de la ACM estuvieron en rango normal para la edad gestacional, incluso en aquellos fetos y recién nacidos que necesitaron recambio sanguíneo y fototerapia postparto, lo que se contrapone con lo descrito en la literatura. Posibles causas de este hallazgo pueden ser: mala toma del peak sistólico, curva demasiado exigente para los casos estudiados y muestra demasiado pequeña. Se requiere seguimiento més largo y una muestra més numerosa. Se realizará un seguimiento con un grupo mayor de pacientes.

Influence of placental malaria infection and maternal hypergammaglobulinaemia on materno-foetal transfer of measles and tetanus antibodies in a rural west African population.

Placental malaria infection jeopardizes pregnancy outcome, and its influence may also impair the transplacental transfer of some antibodies. Two hundred and thirteen Gambian mother-baby pairs were studied to determine the influence of placental malaria infection and maternal hypergammaglobulinaemia on transplacental transfer of measles and tetanus antibodies in Gambian population. Placental blood and tissue were collected for placental malaria diagnosis. Cord and maternal sera were tested for total IgG concentration by laser nephelometry and for IgG antibody to tetanus toxoid and measles by ELISA. The prevalence of placental malaria infection was 51.1%. Mothers whose placentae were parasitized had a significantly higher mean total serum IgG (22.0 g/L vs 11.3 g/L, p < 0.001) and measles antibody level (4.02 IU/mL vs 1.21 IU/mL, p < 0.01), but not tetanus antibody, than mothers with non-parasitized placentae. Results of multiple regression analysis showed that placental malaria infection and maternal hypergammaglobulinaemia were associated with the reduction of 72% (95% CI 67.84) and 86% (95% CI 76.91) in transplacental transfer of measles antibody respectively but did not influence the transfer of tetanus antibody. It is concluded that the combined influence of placental malaria infection and maternal hypergammaglobulinaemia is significantly associated with the transfer of impaired measles antibody in this population.