Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 116
Filtrar
1.
Nutrients ; 13(2)2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-33573262

RESUMO

The placenta is a vital, multi-functional organ that acts as an interface between maternal and fetal circulation during pregnancy. Nutritional deficiencies during pregnancy alter placental development and function, leading to adverse pregnancy outcomes, such as pre-eclampsia, infants with small for gestational age and low birthweight, preterm birth, stillbirths and maternal mortality. Maternal nutritional supplementation may help to mitigate the risks, but the evidence base is difficult to navigate. The primary purpose of this umbrella review is to map the evidence on the effects of maternal nutritional supplements and dietary interventions on pregnancy outcomes related to placental disorders and maternal mortality. A systematic search was performed on seven electronic databases, the PROSPERO register and references lists of identified papers. The results were screened in a three-stage process based on title, abstract and full-text by two independent reviewers. Randomized controlled trial meta-analyses on the efficacy of maternal nutritional supplements or dietary interventions were included. There were 91 meta-analyses included, covering 23 types of supplements and three types of dietary interventions. We found evidence that supports supplementary vitamin D and/or calcium, omega-3, multiple micronutrients, lipid-based nutrients, and balanced protein energy in reducing the risks of adverse maternal and fetal health outcomes. However, these findings are limited by poor quality of evidence. Nutrient combinations show promise and support a paradigm shift to maternal dietary balance, rather than single micronutrient deficiencies, to improve maternal and fetal health. The review is registered at PROSPERO (CRD42020160887).


Assuntos
Suplementos Nutricionais , Terapia Nutricional , Doenças Placentárias/prevenção & controle , Feminino , Humanos , Fenômenos Fisiológicos da Nutrição Materna , Terapia Nutricional/métodos , Gravidez
2.
Malar J ; 19(1): 449, 2020 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-33272281

RESUMO

BACKGROUND: Placental malaria (PM) has been associated with a higher risk of malaria during infancy. However, it is unclear whether this association is causal, and is modified by infant sex, and whether intermittent preventive treatment in pregnancy (IPTp) can reduce infant malaria by preventing PM. METHODS: Data from a birth cohort of 656 infants born to HIV-uninfected mothers randomised to IPTp with dihydroartemisinin-piperaquine (DP) or Sulfadoxine-pyrimethamine (SP) was analysed. PM was categorized as no PM, active PM (presence of parasites), mild-moderate past PM (> 0-20% high powered fields [HPFs] with pigment), or severe past PM (> 20% HPFs with pigment). The association between PM and incidence of malaria in infants stratified by infant sex was examined. Causal mediation analysis was used to test whether IPTp can impact infant malaria incidence via preventing PM. RESULTS: There were 1088 malaria episodes diagnosed among infants during 596.6 person years of follow-up. Compared to infants born to mothers with no PM, the incidence of malaria was higher among infants born to mothers with active PM (adjusted incidence rate ratio [aIRR] 1.30, 95% CI 1.00-1.71, p = 0.05) and those born to mothers with severe past PM (aIRR 1.28, 95% CI 0.89-1.83, p = 0.18), but the differences were not statistically significant. However, when stratifying by infant sex, compared to no PM, severe past PM was associated a higher malaria incidence in male (aIRR 2.17, 95% CI 1.45-3.25, p < 0.001), but not female infants (aIRR 0.74, 95% CI 0.46-1.20, p = 0.22). There were no significant associations between active PM or mild-moderate past PM and malaria incidence in male or female infants. Male infants born to mothers given IPTp with DP had significantly less malaria in infancy than males born to mothers given SP, and 89.7% of this effect was mediated through prevention of PM. CONCLUSION: PM may have more severe consequences for male infants, and interventions which reduce PM could mitigate these sex-specific adverse outcomes. More research is needed to better understand this sex-bias between PM and infant malaria risk. Trial registration ClinicalTrials.gov, NCT02793622. Registered 8 June 2016, https://clinicaltrials.gov/ct2/show/NCT02793622.


Assuntos
Antimaláricos , Malária Falciparum , Doenças Placentárias , Complicações Parasitárias na Gravidez , Adulto , Antimaláricos/administração & dosagem , Antimaláricos/uso terapêutico , Artemisininas/administração & dosagem , Artemisininas/uso terapêutico , Combinação de Medicamentos , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Malária Falciparum/tratamento farmacológico , Malária Falciparum/epidemiologia , Malária Falciparum/prevenção & controle , Masculino , Doenças Placentárias/tratamento farmacológico , Doenças Placentárias/epidemiologia , Doenças Placentárias/parasitologia , Doenças Placentárias/prevenção & controle , Gravidez , Complicações Parasitárias na Gravidez/tratamento farmacológico , Complicações Parasitárias na Gravidez/epidemiologia , Complicações Parasitárias na Gravidez/prevenção & controle , Pirimetamina/administração & dosagem , Pirimetamina/uso terapêutico , Quinolinas/administração & dosagem , Quinolinas/uso terapêutico , Sulfadoxina/administração & dosagem , Sulfadoxina/uso terapêutico , Adulto Jovem
3.
Biol Reprod ; 102(5): 1102-1110, 2020 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-31950133

RESUMO

Preeclampsia is a serious hypertensive disorder of pregnancy, which is only cured with delivery of the placenta, thereby commonly necessitating preterm birth of the fetus. Low-molecular-weight heparin (LMWH) has demonstrated potential to reduce the incidence of preeclampsia in high-risk pregnant women, although the underlying mechanism by which LMWH protects against preeclampsia is unknown. Given the complex structure and biologic actions of heparin, we tested the hypothesis that heparin can mediate preeclampsia prevention via nonanticoagulant pathways. We compared the effects of a nonanticoagulant, glycol-split LMWH (gsHep)-rendered nonanticoagulant through disruption of the antithrombin binding regions-with the LMWH dalteparin in the rat reduced uterine perfusion pressure (RUPP) surgical model of preeclampsia. Although RUPP animals exhibit significantly elevated blood pressure and reduced plasma levels of placental growth factor (PGF) compared to sham, neither dalteparin nor gsHep treatment significantly impacted these parameters. However, the observed positive correlation between PGF levels and number of viable fetuses in RUPP-induced animals suggests that reduced PGF levels were predominately due to placental loss. Daily subcutaneous injections of low-dose dalteparin but not gsHep significantly restored fetal growth that was impaired by RUPP surgery. Placentas from RUPP animals exhibited an abnormal labyrinth structure, characterized by expanded sinusoidal blood spaces, relative to sham-operated animals. Morphometric analysis demonstrated that dalteparin but not gsHep treatment normalized development of the labyrinth in RUPP-exposed conceptuses. These data suggest that the antithrombin-binding regions of LMWH are required to confer its protective effects on fetal growth and placental development.


Assuntos
Dalteparina/farmacologia , Desenvolvimento Fetal/efeitos dos fármacos , Heparina/química , Heparina/metabolismo , Doenças Placentárias/prevenção & controle , Pré-Eclâmpsia/prevenção & controle , Animais , Anticoagulantes/química , Anticoagulantes/farmacologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Hipertensão , Fator de Crescimento Placentário/genética , Fator de Crescimento Placentário/metabolismo , Pré-Eclâmpsia/metabolismo , Pré-Eclâmpsia/patologia , Gravidez , Ratos , Ratos Sprague-Dawley
4.
BMJ Open ; 9(6): e028735, 2019 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-31230027

RESUMO

OBJECTIVES: To identify research priorities and explore potential methodologies to inform care in subsequent pregnancies following a stillbirth. DESIGN: Web-based survey by invitation. PARTICIPANTS: Multidisciplinary panel of 79 individuals involved in stillbirth research, clinical practice and/or advocacy from the international stillbirth research community (response rate=64%). OUTCOME MEASURES: Importance of 16 candidate research topics and perceived utility and appropriateness of randomised controlled trial (RCT) methodology for the evaluation of four pertinent interventions: (1) medical therapies for placental dysfunction (eg, antiplatelet agents); (2) additional antepartum fetal surveillance (eg, ultrasound scans); (3) early planned birth from 37 weeks' gestation and (4) different forms of psychosocial support for parents and families. RESULTS: Candidate research topics that were rated as 'important and urgent' by the greatest proportion of participants were: medical therapies for placental dysfunction (81%); additional antepartum fetal surveillance (80%); the development of a core outcomes dataset for stillbirth research (79%); targeted antenatal interventions for women who have risk factors (79%) and calculating the risk of recurrent stillbirth according to specific causes of index stillbirth (79%). Whether RCT methodologies were considered appropriate for the four selected interventions varied depending on the criterion being assessed. For example, while 72% of respondents felt that RCTs were 'the best way' to evaluate medical therapies for placental dysfunction, fewer respondents (63%) deemed RCTs ethical in this context, and approximately only half (52%) felt that such RCTs were feasible. There was considerably less support for RCT methodology for the evaluation of different forms of psychosocial support, which was reinforced by free-text comments. CONCLUSIONS: Five priority research topics to inform care in pregnancies after stillbirth were identified. There was support for RCTs in this area, but the panel remained divided on the ethics and feasibility of such trials. Engagement with parents and families is a critical next step.


Assuntos
Administração dos Cuidados ao Paciente , Cuidado Pré-Natal/métodos , Projetos de Pesquisa , Pesquisa , Natimorto , Atitude do Pessoal de Saúde , Serviços de Planejamento Familiar/ética , Serviços de Planejamento Familiar/métodos , Feminino , Humanos , Administração dos Cuidados ao Paciente/métodos , Administração dos Cuidados ao Paciente/organização & administração , Doenças Placentárias/diagnóstico , Doenças Placentárias/prevenção & controle , Gravidez , Sistemas de Apoio Psicossocial , Ensaios Clínicos Controlados Aleatórios como Assunto , Risco Ajustado/métodos , Natimorto/epidemiologia , Natimorto/psicologia , Inquéritos e Questionários
6.
Acta Obstet Gynecol Scand ; 97(1): 74-81, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28981981

RESUMO

INTRODUCTION: Mothers at risk of preterm birth are treated with antenatal corticosteroids, which have advantageous effects for prematurely born infants. Accelerated villous maturation in the placenta is also associated with improved perinatal outcome. The primary aim of this study was to examine the association between antenatal corticosteroids and accelerated villous maturation. The secondary aim was to study associations with other placental pathologies. MATERIAL AND METHODS: A retrospective cohort study including 105 women who had (n = 75) or had not (n = 30) been treated with antenatal corticosteroids. The women gave birth between 22+0 and 26+6  weeks of gestation in Stockholm County between 1 April 2004 and 31 March 2007. A pathologist blinded to all clinical data except gestational age examined the placental slides to identify pathology parameters. The outcomes were correlated with antenatal corticosteroid treatment, and confounding factors were adjusted using logistic regression. RESULTS: Accelerated villous maturation was significantly higher in the group treated with corticosteroids (odds ratio 16, 95% CI 2.4-690, p = 0.0005). After adjustment for gestational age and preeclampsia, the difference remained significant (odds ratio 8.9, 95% CI 1.2-389, p = 0.021). No significant associations were found regarding the secondary outcome variables, after adjusting for possible confounders. CONCLUSIONS: Antenatal corticosteroid treatment before preterm birth is associated with accelerated villous maturation. This could be one of the pathways by which corticosteroids are beneficial for preterm infants.


Assuntos
Vilosidades Coriônicas , Glucocorticoides , Doenças Placentárias , Placenta/patologia , Nascimento Prematuro/prevenção & controle , Adulto , Vilosidades Coriônicas/efeitos dos fármacos , Vilosidades Coriônicas/crescimento & desenvolvimento , Feminino , Idade Gestacional , Glucocorticoides/administração & dosagem , Glucocorticoides/efeitos adversos , Humanos , Recém-Nascido , Doenças Placentárias/diagnóstico , Doenças Placentárias/etiologia , Doenças Placentárias/prevenção & controle , Gravidez , Nascimento Prematuro/epidemiologia , Cuidado Pré-Natal/métodos , Cuidado Pré-Natal/estatística & dados numéricos , Estudos Retrospectivos , Medição de Risco , Estatística como Assunto , Suécia/epidemiologia
7.
Curr Opin Obstet Gynecol ; 29(6): 397-403, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28915160

RESUMO

PURPOSE OF REVIEW: Antiphospholipid syndrome (APS) is defined as the association of thrombotic events and/or obstetric morbidity in patients persistently positive for antiphospholipid antibodies (aPL). In this review, we will highlight the most important clinical presentations of APS with a focus on the obstetric morbidity, the current management strategies and the outlook for the future. RECENT FINDINGS: The use of aspirin and heparin has improved the pregnancy outcome in obstetric APS and approximately 70% of pregnant women with APS have a successful pregnancy outcome. Unfortunately, the current standard of care does not prevent all pregnancy complications as the current treatment fails in 20-30% of APS pregnancies. This therefore highlights the need for alternative treatments to improve obstetrical outcome. Other treatment options are currently explored and retrospective studies show that pravastatin for example is beneficial in women with aPL-related early preeclampsia. Moreover, the immunmodulator hydroxychloroquine may play a beneficial role in the prevention of aPL-related pregnancy complications. SUMMARY: APS is among the most frequent acquired risk factors for a treatable cause of recurrent pregnancy loss and increases the risk of conditions associated with ischaemic placental dysfunction, such as fetal growth restriction, preeclampsia, premature birth and intrauterine death. Current treatment is mainly based on aspirin and heparin. Studies to inform on alternative treatment options are urgently needed.


Assuntos
Síndrome Antifosfolipídica/tratamento farmacológico , Doenças Placentárias/etiologia , Pré-Eclâmpsia/prevenção & controle , Aborto Habitual/prevenção & controle , Anticorpos Antifosfolipídeos/sangue , Anticorpos Antifosfolipídeos/imunologia , Anticoagulantes/uso terapêutico , Síndrome Antifosfolipídica/sangue , Síndrome Antifosfolipídica/complicações , Síndrome Antifosfolipídica/imunologia , Aspirina/uso terapêutico , Quimioterapia Combinada , Feminino , Morte Fetal/prevenção & controle , Heparina/uso terapêutico , Humanos , Doenças Placentárias/sangue , Doenças Placentárias/diagnóstico , Doenças Placentárias/prevenção & controle , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/etiologia , Gravidez , Complicações na Gravidez/sangue , Complicações na Gravidez/tratamento farmacológico , Complicações na Gravidez/imunologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos , Fatores de Risco , Natimorto
8.
Placenta ; 60: 115-118, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28473168

RESUMO

Most placental-related pregnancy complications originate during the first trimester of pregnancy where gene-environmental interactions play a role. The environmental factors also include parental behaviors that can be positive, such as folic acid supplement use, or negative, e.g. poor lifestyle choices like smoking, and nutritional choices that contribute to obesity or micronutrient deficits. The overlapping risk factors associated with non-communicable disease are poor nutrition, smoking, and obesity. These modifiable factors differ between individuals, populations and high, middle and low income countries, but have in common that they are extremely difficult to change. Parents-to-be however are most motivated to change poor behaviors when they are aware of short-term health benefits of having a healthy baby. Therefore, these couples should be empowered to use evidence-based and personalized effective tools to improve poor behaviors. Moreover, these tools should be implemented to support healthcare professionals in delivering 'nutrition and lifestyle care' in routine patient care. From this background the usability and effectiveness of the mHealth coaching program www.SmarterPregnancy.co.uk (Dutch version www.SlimmerZwanger.nl) is presented as an opportunity to further customize this tool for specific target groups, healthcare professionals and low resource settings with the potential to prevent placental-related and non-communicable disease during the life course.


Assuntos
Aplicativos Móveis , Doenças Placentárias/prevenção & controle , Cuidado Pré-Concepcional , Cuidado Pré-Natal , Dieta , Feminino , Humanos , Estilo de Vida , Gravidez
9.
Vaccine ; 35(27): 3474-3481, 2017 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-28527688

RESUMO

BACKGROUND: The antigen VAR2CSA plays a pivotal role in the pathophysiology of pregnancy-associated malaria (PAM) caused by Plasmodium falciparum. A VAR2CSA-based vaccine candidate, PAMVAC, is under development by an EU-funded multi-country consortium (PlacMalVac project). As part of PAMVAC's clinical development, we quantified naturally acquired vaccine antigen-specific memory B and T cell responses in Beninese primigravidae recruited at the beginning of pregnancy and followed up to delivery and beyond. METHODS: Clinical and parasitological histories were compiled from monthly clinic visits. On 4 occasions (first and fifth month of pregnancy, delivery, 6months post-delivery) peripheral blood mononuclear cells were isolated for in vitro assays. PAMVAC-specific memory B cells as well as those specific for a PAM unrelated P. falciparum antigen (PfEMP1-CIDR1a) and for tetanus toxoid were quantified by ELISpot. Memory T cell responses were assessed by quantifying cytokines (IL-5, IL-6, IL-10, IL-13, IFN-γ, TNF-α) in supernatants of cells stimulated in vitro either with PAMVAC, or mitogen (PHA). RESULTS: Both tetanus toxoid- and PAMVAC-specific memory B cell frequencies increased to reach peak levels in the 5th month and at delivery, respectively and persisted post-delivery. The frequency of CIDR1a-specific memory B cells was stable during pregnancy, but declined post-delivery. The cumulated prevalence of infection with P. falciparum during pregnancy was 61% by microscopy. In women with a history of such infections, a significantly higher frequency of PAMVAC-specific memory B cells was observed at delivery. PAMVAC-specific pro-inflammatory (IFN-γ, TNF) responses tended to be higher at delivery in those with a history of infection. Mitogen-induced IL-5/IL-13 responses were significantly enhanced in the same women. CONCLUSIONS: PAMVAC-specific memory B cells are induced during first pregnancies and are maintained post-delivery. Women with a T helper cell profile biased towards production of Th2-type cytokines have a greater risk of infection with P. falciparum.


Assuntos
Antígenos de Protozoários/imunologia , Linfócitos B/imunologia , Vacinas Antimaláricas/imunologia , Malária Falciparum/prevenção & controle , Doenças Placentárias/prevenção & controle , Complicações Infecciosas na Gravidez/prevenção & controle , Linfócitos T/imunologia , Adolescente , Adulto , Benin , Citocinas/metabolismo , ELISPOT , Feminino , Humanos , Recém-Nascido , Gravidez , Adulto Jovem
10.
Expert Rev Vaccines ; 16(6): 613-624, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28434376

RESUMO

INTRODUCTION: Malaria during pregnancy is a massive health problem in endemic areas. Placental malaria infections caused by Plasmodium falciparum are responsible for up to one million babies being born with a low birth weight every year. Significant efforts have been invested into preventing the condition. Areas covered: Pub Med was searched using the broad terms 'malaria parasite placenta' to identify studies of interactions between parasite and host, 'prevention of placental malaria' to identify current strategies to prevent placental malaria, and 'placental malaria vaccine' to identify pre-clinical vaccine development. However, all papers from these searches were not systematically included. Expert commentary: The first phase I clinical trials of vaccines are well underway. Trials testing efficacy are more complicated to carry out as only women that are exposed to parasites during pregnancy will contribute to endpoint measurements, further it may require extensive follow-up to establish protection. Future second generation vaccines may overcome the inherent challenges in making an effective placental malaria vaccine.


Assuntos
Vacinas Antimaláricas/imunologia , Vacinas Antimaláricas/isolamento & purificação , Malária Falciparum/prevenção & controle , Doenças Placentárias/prevenção & controle , Plasmodium falciparum/imunologia , Complicações Infecciosas na Gravidez/prevenção & controle , Ensaios Clínicos Fase I como Assunto , Descoberta de Drogas/tendências , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Gravidez
12.
Thromb Res ; 151 Suppl 1: S38-S42, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28262232

RESUMO

Placenta-mediated pregnancy complications, such as pre-eclampsia, placental abruption, birth of a small-for-gestational age infant and late pregnancy loss, are common and carry significant morbidity and mortality. The etiology of placenta-mediated pregnancy complications is likely multifactorial and may include abnormal coagulation activation of the maternal-fetal interface. The use of antepartum low-molecular-weight heparin (LMWH) prophylaxis to prevent recurrent placenta-mediated pregnancy complications has become common practice despite limited and conflicting evidence to support its use. This paper reviews the evidence, including recently published data from an individual patient level meta-analysis, which challenges the role of LMWH in preventing recurrent placenta-mediated pregnancy complications. Incorporating this recent evidence, we recommend against the use of LMWH to prevent recurrent placenta-mediated pregnancy complications in women with and without inherited thrombophilia.


Assuntos
Anticoagulantes/uso terapêutico , Heparina de Baixo Peso Molecular/uso terapêutico , Doenças Placentárias/prevenção & controle , Placenta/efeitos dos fármacos , Complicações Hematológicas na Gravidez/tratamento farmacológico , Trombofilia/tratamento farmacológico , Aspirina/uso terapêutico , Feminino , Fibrinolíticos/uso terapêutico , Humanos , Placenta/patologia , Doenças Placentárias/patologia , Pré-Eclâmpsia/patologia , Pré-Eclâmpsia/prevenção & controle , Gravidez , Complicações Hematológicas na Gravidez/patologia , Recidiva , Prevenção Secundária , Trombofilia/complicações , Trombofilia/patologia
13.
Clin Obstet Gynecol ; 60(1): 153-160, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28005590

RESUMO

During the past decade, prophylactic doses of low-molecular-weight heparin (LMWH) have been suggested to decrease the risk of placental-mediated complications. Herein, we review the prospective randomized trials that addressed the usefulness of LMWH in preventing placental-mediated complications in high-risk women. Inclusion criteria and results of these trials are heterogeneous. Unlike older trials (3 of 4 are single center), recent trials (all are multicenter) do not show beneficial effect of LMWH. There is certainly a need of complementary research before stating on the usefulness of LMWH in the prevention of placenta-mediated pregnancy complications in women at high risk.


Assuntos
Anticoagulantes/administração & dosagem , Heparina de Baixo Peso Molecular/administração & dosagem , Doenças Placentárias/prevenção & controle , Pré-Eclâmpsia/prevenção & controle , Complicações na Gravidez/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto , Feminino , Humanos , Placenta , Gravidez
14.
Vaccine ; 35(4): 610-618, 2017 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-28012775

RESUMO

BACKGROUND: Malaria in pregnancy is associated with significant morbidity in pregnant women and their offspring. Plasmodium falciparum infected erythrocytes (IE) express VAR2CSA that mediates binding to chondroitin sulphate A (CSA) in the placenta. Two VAR2CSA-based vaccines for placental malaria are in clinical development. The purpose of this study was to evaluate the robustness and comparability of binding inhibition assays used in the clinical development of placental malaria vaccines. METHODS: The ability of sera from animals immunised with different VAR2CSA constructs to inhibit IE binding to CSA was investigated in three in vitro assays using 96-well plates, petri dishes, capillary flow and an ex vivo placental perfusion assay. RESULTS: The inter-assay variation was not uniform between assays and ranged from above ten-fold in the flow assay to two-fold in the perfusion assay. The intra-assay variation was highest in the petri dish assay. A positive correlation between IE binding avidity and the level of binding after antibody inhibition in the petri dish assay indicate that high avidity IE binding is more difficult to inhibit. The highest binding inhibition sensitivity was found in the 96-well and petri dish assays compared to the flow and perfusion assays where binding inhibition required higher antibody titers. CONCLUSIONS: The inhibitory capacity of antibodies is not easily translated between assays and the high sensitivity of the 96-well and petri dish assays stresses the need for comparing serial dilutions of serum. Furthermore, IE binding avidity must be in the same range when comparing data from different days. There was an overall concordance in the capacity of antibody-mediated inhibition, when comparing the in vitro assays with the perfusion assay, which more closely represents in vivo conditions. Importantly the ID1-ID2a protein in a liposomal formulation, currently in a phase I trial, effectively induced antibodies that inhibited IE adhesion in placental tissue.


Assuntos
Anticorpos Antiprotozoários/sangue , Adesão Celular , Sulfatos de Condroitina/metabolismo , Técnicas Citológicas/métodos , Eritrócitos/fisiologia , Malária Falciparum/prevenção & controle , Doenças Placentárias/prevenção & controle , Animais , Antígenos de Protozoários/imunologia , Descoberta de Drogas/métodos , Eritrócitos/parasitologia , Feminino , Vacinas Antimaláricas/administração & dosagem , Vacinas Antimaláricas/imunologia , Camundongos Endogâmicos C57BL , Gravidez , Coelhos , Ratos Wistar , Reprodutibilidade dos Testes
15.
Lancet ; 388(10060): 2629-2641, 2016 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-27720497

RESUMO

BACKGROUND: Placenta-mediated pregnancy complications include pre-eclampsia, late pregnancy loss, placental abruption, and birth of a small-for-gestational-age (SGA) neonate. These complications are leading causes of maternal, fetal, and neonatal morbidity and mortality in high-income countries. Affected women are at high risk of recurrence in subsequent pregnancies; however, effective strategies to prevent recurrence are absent. Findings from our previous study-level meta-analysis suggested that low-molecular-weight heparin reduced the risk of recurrent placenta-mediated pregnancy complications. However, we identified significant heterogeneity in the results, possibly due to trial design or inclusion criteria. To identify which patients benefit from, and which outcomes are prevented by, low-molecular-weight heparin, we did an individual patient data meta-analysis. METHODS: We did a systematic review in May, 2013, which identified eight eligible randomised trials done between 2000 and 2013 of low-molecular-weight heparin to prevent recurrent placenta-mediated pregnancy complications. We excluded studies on the basis of the wrong population, the study being ongoing, inability to confirm eligibility of participants, intervention stopped too early, and no response from the principal investigator. We requested individual patient data from the study authors for eligible women (women pregnant at the time of the study with a history of previous pregnancy that had been complicated by one or more of the following: pre-eclampsia, placental abruption, birth of an SGA neonate [<10th percentile], pregnancy loss after 16 weeks' gestation, or two losses after 12 weeks' gestation) and recoded, combined, and analysed the data for our meta-analysis. The primary outcome was a composite of early-onset (<34 weeks) or severe pre-eclampsia, birth of an SGA neonate (<5th percentile), late pregnancy loss (≥20 weeks' gestation), or placental abruption leading to delivery, assessed on an intention-to-treat basis. We assessed risk of bias with the Cochrane Risk of Bias tool. This study is registered with PROSPERO, number CRD42013006249. FINDINGS: We analysed data from 963 eligible women in eight trials: 480 randomly assigned to low-molecular-weight heparin and 483 randomly assigned to no low-molecular-weight heparin. Overall, the risk of bias was not substantial enough to affect decisions regarding trial inclusion. Participants were mostly white (795/905; 88%) with a mean age of 30·9 years (SD 5·0) and 403/963 (42%) had thrombophilia. In the primary analysis, low-molecular-weight heparin did not significantly reduce the risk of recurrent placenta-mediated pregnancy complications (low-molecular-weight heparin 62/444 [14%] versus no low-molecular-weight heparin 95/443 (22%) absolute difference -8%, 95% CI -17·3 to 1·4, p=0·09; relative risk 0·64, 95% CI 0·36-1·11, p=0·11). We noted significant heterogeneity between single-centre and multicentre trials. In subgroup analyses, low-molecular-weight heparin in multicentre trials reduced the primary outcome in women with previous abruption (p=0·006) but not in any of the other subgroups of previous complications. INTERPRETATION: Low-molecular-weight heparin does not seem to reduce the risk of recurrent placenta-mediated pregnancy complications in at-risk women. However, some decreases in event rates might have been too small for the power of our study to explore. FUNDING: Canadian Institutes of Health Research.


Assuntos
Heparina de Baixo Peso Molecular/uso terapêutico , Doenças Placentárias/prevenção & controle , Complicações na Gravidez/tratamento farmacológico , Adulto , Parto Obstétrico , Feminino , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Pré-Eclâmpsia/etiologia , Gravidez , Complicações na Gravidez/etiologia , Complicações na Gravidez/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto , Trombofilia/complicações
16.
Semin Thromb Hemost ; 42(7): 780-788, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27652601

RESUMO

Antiphospholipid syndrome (APS) is classified as the association of thrombotic events and/or obstetric morbidity in patients persistently positive for antiphospholipid antibodies (aPL). APS is also the most frequently acquired risk factor for a treatable cause of recurrent pregnancy loss and increases the risk of conditions associated with ischemic placental dysfunction, such as stillbirth, intrauterine death, preeclampsia, premature birth, and fetal growth restriction. The use of low-dose aspirin and heparin has improved the pregnancy outcome in obstetric APS and approximately 70% of pregnant women with APS will deliver a viable live infant. However, current management does not prevent all maternal, fetal, and neonatal complications of APS and the current treatment fails in 20 to 30% of APS pregnancies, raising the need to explore other treatments to improve obstetrical outcome. Two clinical studies of retrospective design have suggested that the immunomodulator hydroxychloroquine (HCQ) may play a role in the prevention of pregnancy complications in women with aPL and APS. The randomized controlled multicenter trial of hydroxychloroquine versus placebo during pregnancy in women with antiphospholipid antibodies (HYPATIA) of HCQ versus placebo will provide scientific evidence on the use of HCQ in pregnant women with aPL.


Assuntos
Síndrome Antifosfolipídica , Retardo do Crescimento Fetal , Hidroxicloroquina/uso terapêutico , Doenças Placentárias , Pré-Eclâmpsia , Nascimento Prematuro , Anticorpos Antifosfolipídeos/sangue , Síndrome Antifosfolipídica/sangue , Síndrome Antifosfolipídica/complicações , Síndrome Antifosfolipídica/diagnóstico , Síndrome Antifosfolipídica/tratamento farmacológico , Feminino , Retardo do Crescimento Fetal/sangue , Retardo do Crescimento Fetal/diagnóstico , Retardo do Crescimento Fetal/etiologia , Retardo do Crescimento Fetal/prevenção & controle , Humanos , Doenças Placentárias/sangue , Doenças Placentárias/diagnóstico , Doenças Placentárias/etiologia , Doenças Placentárias/prevenção & controle , Pré-Eclâmpsia/sangue , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/etiologia , Pré-Eclâmpsia/prevenção & controle , Gravidez , Nascimento Prematuro/sangue , Nascimento Prematuro/diagnóstico , Nascimento Prematuro/etiologia , Nascimento Prematuro/prevenção & controle
17.
Womens Health (Lond) ; 12(4): 433-41, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27638899

RESUMO

Adverse pregnancy outcomes, such as pregnancy loss and pre-eclampsia, are associated with thrombotic mechanisms and thrombophilia. Antithrombotic interventions, particularly low-molecular-weight heparin, have been investigated in women identified by previous pregnancy outcome; however, the results have been inconsistent. This may reflect heterogeneity of both the study groups and the disease processes resulting in inadequate stratification to guide antithrombotic interventions. Furthermore, the variation in gestation at initiation of low-molecular-weight heparin treatment might be important. Despite limited evidence of efficacy, low-molecular-weight heparin is often used in an attempt to prevent these complications, owing to the lack of other effective treatments and its perceived safety in pregnancy. Research is required to better understand the disease processes, identify possible biomarkers and thereby more homogeneous groups for targeted treatment.


Assuntos
Doenças Placentárias/prevenção & controle , Complicações na Gravidez/tratamento farmacológico , Trombofilia/complicações , Anticoagulantes/uso terapêutico , Feminino , Humanos , Gravidez , Complicações na Gravidez/prevenção & controle , Trombofilia/tratamento farmacológico
18.
Malar J ; 15: 476, 2016 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-27639691

RESUMO

Placental malaria caused by Plasmodium falciparum infection constitutes a major health problem manifesting as severe disease and anaemia in the mother, impaired fetal development, low birth weight or spontaneous abortion. Prevention of placental malaria currently relies on two key strategies that are losing efficacy due to spread of resistance: long-lasting insecticide-treated nets and intermittent preventive treatment during pregnancy. A placental malaria vaccine would be an attractive, cost-effective complement to the existing control tools. Two placental malaria vaccine candidates are currently in Phase Ia/b clinical trials. During two workshops hosted by the European Vaccine Initiative, one in Paris in April 2014 and the other in Brussels in November 2014, the main actors in placental malaria vaccine research discussed the harmonization of clinical development plans and of the immunoassays with a goal to define standards that will allow comparative assessment of different placental malaria vaccine candidates. The recommendations of these workshops should guide researchers and clinicians in the further development of placental malaria vaccines.


Assuntos
Imunoensaio/métodos , Vacinas Antimaláricas/imunologia , Vacinas Antimaláricas/isolamento & purificação , Malária Falciparum/diagnóstico , Malária Falciparum/prevenção & controle , Doenças Placentárias/diagnóstico , Doenças Placentárias/prevenção & controle , Bélgica , Ensaios Clínicos Fase I como Assunto , Educação , Feminino , Humanos , Paris , Desenvolvimento Vegetal , Gravidez
19.
Proc Natl Acad Sci U S A ; 113(22): 6265-70, 2016 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-27185937

RESUMO

Fetoplacental glucocorticoid overexposure is a significant mechanism underlying fetal growth restriction and the programming of adverse health outcomes in the adult. Placental glucocorticoid inactivation by 11ß-hydroxysteroid dehydrogenase type 2 (11ß-HSD2) plays a key role. We previously discovered that Hsd11b2(-/-) mice, lacking 11ß-HSD2, show marked underdevelopment of the placental vasculature. We now explore the consequences for fetal cardiovascular development and whether this is reversible. We studied Hsd11b2(+/+), Hsd11b2(+/-), and Hsd11b2(-/-) littermates from heterozygous (Hsd11b(+/-)) matings at embryonic day (E)14.5 and E17.5, where all three genotypes were present to control for maternal effects. Using high-resolution ultrasound, we found that umbilical vein blood velocity in Hsd11b2(-/-) fetuses did not undergo the normal gestational increase seen in Hsd11b2(+/+) littermates. Similarly, the resistance index in the umbilical artery did not show the normal gestational decline. Surprisingly, given that 11ß-HSD2 absence is predicted to initiate early maturation, the E/A wave ratio was reduced at E17.5 in Hsd11b2(-/-) fetuses, suggesting impaired cardiac function. Pravastatin administration from E6.5, which increases placental vascular endothelial growth factor A and, thus, vascularization, increased placental fetal capillary volume, ameliorated the aberrant umbilical cord velocity, normalized fetal weight, and improved the cardiac function of Hsd11b2(-/-) fetuses. This improved cardiac function occurred despite persisting indications of increased glucocorticoid exposure in the Hsd11b2(-/-) fetal heart. Thus, the pravastatin-induced enhancement of fetal capillaries within the placenta and the resultant hemodynamic changes correspond with restored fetal cardiac function. Statins may represent a useful therapeutic approach to intrauterine growth retardation due to placental vascular hypofunction.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 2/fisiologia , Retardo do Crescimento Fetal/prevenção & controle , Glucocorticoides/metabolismo , Cardiopatias/prevenção & controle , Doenças Placentárias/prevenção & controle , Pravastatina/farmacologia , Animais , Anticolesterolemiantes/farmacologia , Feminino , Retardo do Crescimento Fetal/metabolismo , Retardo do Crescimento Fetal/patologia , Cardiopatias/metabolismo , Cardiopatias/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Doenças Placentárias/metabolismo , Doenças Placentárias/patologia , Gravidez , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
20.
J Matern Fetal Neonatal Med ; 29(6): 855-62, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25893545

RESUMO

Massive perivillous fibrin deposition of the placenta (MPFD) or maternal floor infarction (MFI) is a serious condition associated with recurrent complications including fetal death and severe fetal growth restriction. There is no method to evaluate the risk of adverse outcome in subsequent pregnancies, or effective prevention. Recent observations suggest that MFI is characterized by an imbalance in angiogenic/anti-angiogenic factors in early pregnancy; therefore, determination of these biomarkers may identify the patient at risk for recurrence. We report the case of a pregnant woman with a history of four consecutive pregnancy losses, the last of which was affected by MFI. Abnormalities of the anti-angiogenic factor, sVEGFR-1, and soluble endoglin (sEng) were detected early in the index pregnancy, and treatment with pravastatin corrected the abnormalities. Treatment resulted in a live birth infant at 34 weeks of gestation who had normal biometric parameters and developmental milestones at the age of 2. This is the first reported successful use of pravastatin to reverse an angiogenic/anti-angiogenic imbalance and prevent fetal death.


Assuntos
Aborto Habitual/etiologia , Aborto Habitual/prevenção & controle , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Doenças Placentárias/prevenção & controle , Pravastatina/uso terapêutico , Aborto Habitual/sangue , Adulto , Animais , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Imunoglobulinas Intravenosas/uso terapêutico , Doenças Placentárias/sangue , Pravastatina/farmacologia , Gravidez , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/sangue
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...