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1.
PLoS Biol ; 20(5): e3001544, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35617356

RESUMO

The Red List of Threatened Species, published by the International Union for Conservation of Nature (IUCN), is a crucial tool for conservation decision-making. However, despite substantial effort, numerous species remain unassessed or have insufficient data available to be assigned a Red List extinction risk category. Moreover, the Red Listing process is subject to various sources of uncertainty and bias. The development of robust automated assessment methods could serve as an efficient and highly useful tool to accelerate the assessment process and offer provisional assessments. Here, we aimed to (1) present a machine learning-based automated extinction risk assessment method that can be used on less known species; (2) offer provisional assessments for all reptiles-the only major tetrapod group without a comprehensive Red List assessment; and (3) evaluate potential effects of human decision biases on the outcome of assessments. We use the method presented here to assess 4,369 reptile species that are currently unassessed or classified as Data Deficient by the IUCN. The models used in our predictions were 90% accurate in classifying species as threatened/nonthreatened, and 84% accurate in predicting specific extinction risk categories. Unassessed and Data Deficient reptiles were considerably more likely to be threatened than assessed species, adding to mounting evidence that these species warrant more conservation attention. The overall proportion of threatened species greatly increased when we included our provisional assessments. Assessor identities strongly affected prediction outcomes, suggesting that assessor effects need to be carefully considered in extinction risk assessments. Regions and taxa we identified as likely to be more threatened should be given increased attention in new assessments and conservation planning. Lastly, the method we present here can be easily implemented to help bridge the assessment gap for other less known taxa.


Assuntos
Conservação dos Recursos Naturais , Extinção Biológica , Animais , Biodiversidade , Espécies em Perigo de Extinção , Humanos , Filogenia , Répteis
2.
Prenat Diagn ; 44(8): 959-964, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38757850

RESUMO

AIM: This aim of this study was to detail maternal and fetal anomalies observed on a national scale in a large French cohort of patients presenting high hCG values (≥10 multiple of the median [MoM]) at Down syndrome screening in order to define clear and optimal guidelines. METHODS: This is a retrospective multicenter study based on a French annual database of all trisomy 21 screenings. Our study targeted and studied cases with hCG or hCGß values ≥10 MoM. Complementary exams and outcomes were analyzed. RESULTS: The calculated frequency was 0.05% for hCGß ≥10 MoM in unselected patients. For this series of 289 cases, a complication of the pregnancy or a poor outcome was observed in 145 cases (51%) as follows: 96 (66%) cases of fetal disease, 23 (16%) of maternal disease, 5 (3.5%) of placental anomalies and 21 (14.5%) of systemic disease concerning mother, fetus and placenta. CONCLUSION: This study establishes the frequency of hCG or hCGß values ≥10 MoM, presents a flow chart that optimizes follow-up, and gives clear information for patients presenting with such abnormal values at trisomy 21 screening.


Assuntos
Gonadotropina Coriônica Humana Subunidade beta , Síndrome de Down , Humanos , Síndrome de Down/diagnóstico , Síndrome de Down/sangue , Síndrome de Down/epidemiologia , Feminino , Gravidez , Estudos Retrospectivos , Gonadotropina Coriônica Humana Subunidade beta/sangue , Adulto , Guias de Prática Clínica como Assunto , Biomarcadores/sangue , Diagnóstico Pré-Natal/métodos , Diagnóstico Pré-Natal/estatística & dados numéricos , Diagnóstico Pré-Natal/normas , Testes para Triagem do Soro Materno/estatística & dados numéricos
3.
Prenat Diagn ; 44(5): 555-561, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38448008

RESUMO

OBJECTIVE: In singleton pregnancies, the use of cell-free DNA (cfDNA) analysis as a screening test for common fetal trisomies has spread worldwide though we still lack sufficient data for its use in triplet pregnancies. The objective of this study is to assess the performance of cfDNA testing in detecting fetal aneuploidies in triplet pregnancies as a first-tier test. METHOD: We performed a retrospective cohort study including data from pregnant women with a triplet pregnancy who underwent cfDNA testing between May 1, 2017, and January 15, 2020. cfDNA was obtained by massive parallel sequencing (VeriSeq NIPT solution; Illumina®). The objectives of the study were to assess the diagnostic performance of cfDNA testing for trisomy 21 (T21) (primary outcome), trisomy 18 (T18) and 13 (secondary outcomes). RESULTS: During the study period, cfDNA testing was performed in 255 women with triplet pregnancy, of which 165 (64.7%) had a neonatal outcome available. Three tests were positive for T21, one of which was confirmed by an antenatal karyotype, and the other was confirmed at birth. The third case did not undergo an invasive procedure and was not confirmed at birth (false positive). In one case, cfDNA testing was positive for T18 and was confirmed by an antenatal karyotype. There were no cases of trisomy 13 in the cohort. The no-call rate was 2.4% at first sampling. Fifty-eight (22.7%) women had embryo reduction, which in 40 (69%) of whom was performed after the cfDNA test result. CONCLUSION: cfDNA testing could be offered as primary screening for main fetal aneuploidies in triplet pregnancies after provision of appropriate patient information.


Assuntos
Ácidos Nucleicos Livres , Gravidez de Trigêmeos , Humanos , Feminino , Gravidez , Estudos Retrospectivos , Ácidos Nucleicos Livres/sangue , Ácidos Nucleicos Livres/análise , Adulto , Síndrome da Trissomía do Cromossomo 18/diagnóstico , Síndrome da Trissomía do Cromossomo 18/genética , Síndrome da Trissomía do Cromossomo 18/sangue , Trissomia/diagnóstico , Trissomia/genética , Teste Pré-Natal não Invasivo/métodos , Teste Pré-Natal não Invasivo/estatística & dados numéricos , Teste Pré-Natal não Invasivo/normas , Síndrome da Trissomia do Cromossomo 13/diagnóstico , Síndrome da Trissomia do Cromossomo 13/sangue , Síndrome da Trissomia do Cromossomo 13/genética , Estudos de Coortes , Síndrome de Down/diagnóstico , Síndrome de Down/genética , Testes para Triagem do Soro Materno/métodos , Testes para Triagem do Soro Materno/estatística & dados numéricos , Diagnóstico Pré-Natal/métodos , Diagnóstico Pré-Natal/normas
4.
Acta Obstet Gynecol Scand ; 103(1): 51-58, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37942915

RESUMO

INTRODUCTION: The aim of this study is to evaluate the benefit of cytogenetic testing by amniocentesis after an ultrasound diagnosis of isolated bilateral talipes equinovarus. MATERIAL AND METHODS: This multicenter observational retrospective study includes all prenatally diagnosed cases of isolated bilateral talipes equinovarus in five fetal medicine centers from 2012 through 2021. Ultrasound data, amniocentesis results, biochemical analyses of amniotic fluid and parental blood samples to test neuromuscular diseases, pregnancy outcomes, and postnatal outcomes were collected for each patient. RESULTS: In all, 214 fetuses with isolated bilateral talipes equinovarus were analyzed. A first-degree family history of talipes equinovarus existed in 9.8% (21/214) of our cohort. Amniocentesis was proposed to 86.0% (184/214) and performed in 70.1% (129/184) of cases. Of the 184 karyotypes performed, two (1.6%) were abnormal (one trisomy 21 and one triple X syndrome). Of the 103 microarrays performed, two (1.9%) revealed a pathogenic copy number variation (one with a de novo 18p deletion and one with a de novo 22q11.2 deletion) (DiGeorge syndrome). Neuromuscular diseases (spinal muscular amyotrophy, myasthenia gravis, and Steinert disease) were tested for in 56 fetuses (27.6%); all were negative. Overall, 97.6% (165/169) of fetuses were live-born, and the diagnosis of isolated bilateral talipes equinovarus was confirmed for 98.6% (139/141). Three medical terminations of pregnancy were performed (for the fetuses diagnosed with Down syndrome, DiGeorge syndrome, and the 18p deletion). Telephone calls (at a mean follow-up age of 4.5 years) were made to all parents to collect medium-term and long-term follow-up information, and 70 (33.0%) families were successfully contacted. Two reported a rare genetic disease diagnosed postnatally (one primary microcephaly and one infantile glycine encephalopathy). Parents did not report any noticeably abnormal psychomotor development among the other children during this data collection. CONCLUSIONS: Despite the low rate of pathogenic chromosomal abnormalities diagnosed prenatally after this ultrasound diagnosis, the risk of chromosomal aberration exceeds the risks of amniocentesis. These data may be helpful in prenatal counseling situations.


Assuntos
Pé Torto Equinovaro , Doenças Neuromusculares , Pé Torto , Gravidez , Feminino , Criança , Humanos , Pré-Escolar , Pé Torto Equinovaro/diagnóstico por imagem , Pé Torto Equinovaro/genética , Amniocentese , Estudos Retrospectivos , Variações do Número de Cópias de DNA , Diagnóstico Pré-Natal/métodos , Aberrações Cromossômicas , Líquido Amniótico
5.
Biostatistics ; 22(2): 365-380, 2021 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-31612223

RESUMO

The estimated accuracy of a classifier is a random quantity with variability. A common practice in supervised machine learning, is thus to test if the estimated accuracy is significantly better than chance level. This method of signal detection is particularly popular in neuroimaging and genetics. We provide evidence that using a classifier's accuracy as a test statistic can be an underpowered strategy for finding differences between populations, compared to a bona fide statistical test. It is also computationally more demanding than a statistical test. Via simulation, we compare test statistics that are based on classification accuracy, to others based on multivariate test statistics. We find that the probability of detecting differences between two distributions is lower for accuracy-based statistics. We examine several candidate causes for the low power of accuracy-tests. These causes include: the discrete nature of the accuracy-test statistic, the type of signal accuracy-tests are designed to detect, their inefficient use of the data, and their suboptimal regularization. When the purpose of the analysis is the evaluation of a particular classifier, not signal detection, we suggest several improvements to increase power. In particular, to replace V-fold cross-validation with the Leave-One-Out Bootstrap.


Assuntos
Neuroimagem , Aprendizado de Máquina Supervisionado , Simulação por Computador , Humanos , Probabilidade
6.
Eur Respir J ; 59(2)2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34266941

RESUMO

OBJECTIVES: Most children with prenatally diagnosed congenital pulmonary malformations (CPMs) are asymptomatic at birth. We aimed to develop a parsimonious prognostic model for predicting the risk of neonatal respiratory distress (NRD) in preterm and term infants with CPM, based on the prenatal attributes of the malformation. METHODS: MALFPULM is a prospective population-based nationally representative cohort including 436 pregnant women. The main predictive variable was the CPM volume ratio (CVR) measured at diagnosis (CVR first) and the highest CVR measured (CVR max). Separate models were estimated for preterm and term infants and were validated by bootstrapping. RESULTS: In total, 67 of the 383 neonates studied (17%) had NRD. For infants born at term (>37 weeks, n=351), the most parsimonious model included CVR max as the only predictive variable (receiver operating characteristic (ROC) curve area: 0.70±0.04, negative predictive value: 0.91). The probability of NRD increased linearly with increasing CVR max and remained below 10% for CVR max <0.4. In preterm infants (n=32), both CVR max and gestational age were important predictors of the risk of NRD (ROC: 0.85±0.07). Models based on CVR first had a similar predictive ability. CONCLUSIONS: Predictive models based exclusively on CVR measurements had a high negative predictive value in infants born at term. Our study results could contribute to the individualised general risk assessment to guide decisions about the need for newborns with prenatally diagnosed CPM to be delivered at specialised centres.


Assuntos
Síndrome do Desconforto Respiratório , Ultrassonografia Pré-Natal , Criança , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Gravidez , Estudos Prospectivos , Fatores de Risco , Ultrassonografia Pré-Natal/métodos
7.
Prenat Diagn ; 42(4): 428-434, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35238062

RESUMO

Congenital ventricular diverticulum (VD) and aneurysm are rare cardiac developmental anomalies and their pathophysiology is still unclear. They present as an anomaly of the four chambers view, cardiomegaly, arrhythmia, pericardial effusion, or hydrops. They are usually isolated anomalies. Differential diagnosis between diverticulum and aneurysm is challenging during the prenatal period. Management policy is not uniform either conservative or repeated pericardial puncture. OBJECTIVE: We wanted to describe prenatal features and post-natal outcomes of fetal cardiac out pouching. METHODS: We retrospectively report 6 cases of VD and aneurysm prenatally managed in our fetal medicine unit between 2010 and 2020. All cases were evaluated from the first or second trimester of pregnancy until postnatal follow-up (3 months to 3 years). RESULTS: All six cases underwent a monthly ultrasound follow-up with spontaneous regression of pericardial effusion, and normal hemodynamics at birth No pericardial puncture was done and postnatal outcome was favorable in all cases. CONCLUSION: Based on our experience and on cases previously published, prenatal counseling should be prudent regarding the final diagnosis. Referral and monthly prenatal ultrasound follow-up, birth in a tertiary center after multidisciplinary evaluation and cardiological evaluation at birth still seem mandatory.


Assuntos
Aneurisma , Divertículo , Cardiopatias Congênitas , Derrame Pericárdico , Divertículo/diagnóstico por imagem , Feminino , Cardiopatias Congênitas/diagnóstico por imagem , Humanos , Recém-Nascido , Gravidez , Diagnóstico Pré-Natal , Estudos Retrospectivos , Ultrassonografia Pré-Natal
8.
Prenat Diagn ; 41(4): 434-439, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33350492

RESUMO

OBJECTIVE: Congenital diarrheal disorders (CDDs) are a group of rare diseases among which some present as inherited disorders of intestinal electrolyte transportation: congenital chloride diarrhea (CCD) and congenital sodium diarrhea (CSD) with prenatal manifestations, mainly polyhydramnios, leading to premature delivery. Affected neonates present with watery stools, sometimes mistaken as urine, leading to a misdiagnosis of Bartter syndrome. The aim of this study was to study the value of a prenatal biochemical pattern in the case of suspected CDD. METHODS: We retrospectively studied 12 amniotic fluids of CDD-affected fetuses prenatally suspected and confirmed after birth. Digestive enzymes, proteins, and electrolytes were assayed and showed abnormal biochemical patterns. RESULTS: The 12 infants (eight CCD- and four CSD-affected) were born prematurely with a normal birth weight. Electrolytes and the Bartter index were normal for all cases. Amniotic fluid enzyme patterns were abnormal: anal leakage for nine, as expected, but vomiting of bile was observed for three infants, for whom an occlusive syndrome required surgery, and thereafter severe complications appeared with a poor prognosis. CONCLUSION: Amniotic fluid biochemical patterns differentiate CDD from Bartter syndrome. If a vomiting bile pattern is observed, postnatal management should take into account the hypothesis of a most severe complication.


Assuntos
Diarreia/congênito , Erros Inatos do Metabolismo/diagnóstico , Diarreia/diagnóstico , Diarreia/epidemiologia , Diarreia/genética , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Erros Inatos do Metabolismo/epidemiologia , Erros Inatos do Metabolismo/genética , Teste Pré-Natal não Invasivo/métodos , Teste Pré-Natal não Invasivo/estatística & dados numéricos , Paris/epidemiologia , Gravidez , Estudos Retrospectivos
9.
Fetal Diagn Ther ; 48(4): 265-271, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33756463

RESUMO

OBJECTIVE: The objective of our study was to assess the utility of sequential fetal urine analysis in severe lower urinary tract obstruction (LUTO) when selecting cases suitable for vesicoamniotic shunting. MATERIAL AND METHODS: This was a retrospective cohort study of cases of severe LUTO treated in our fetal medicine center from 1994 to 2013. Two fetal bladder samples were taken 24-48 h apart to assess renal function. A vesicoamniotic shunt was inserted in case of improvement in urinary biochemistry between the 2 samples. We assessed perinatal morbidity and mortality and renal function at 5 years. RESULTS: Among a total of 26 LUTO cases with sequential urine analysis, 5 showed normal urinary biochemistry, 13 were abnormal, and 8 improved between the 2 samples. These 8 cases underwent vesicoamniotic shunt placement, leading to the birth of 6/8 (75%) live infants, 5/6 (83%) of whom had normal renal function at 5 years. The 5 cases with normal biochemistry occasioned 2 neonatal deaths and 3 children with normal renal function at 5 years. Elective termination of pregnancy was requested by parents for the fetuses exhibiting abnormal biochemistry. CONCLUSION: An improvement in urinary biochemistry between 2 sequential fetal bladder punctures in severe LUTO could be an effective criterion in the selection of candidates for vesicoamniotic shunting. However, the benefit of a shunt in fetuses with normal amniotic fluid remains to be evaluated in clinical trials.


Assuntos
Doenças Fetais , Obstrução Uretral , Líquido Amniótico , Criança , Feminino , Doenças Fetais/diagnóstico por imagem , Doenças Fetais/cirurgia , Humanos , Lactente , Recém-Nascido , Gravidez , Estudos Retrospectivos , Ultrassonografia Pré-Natal , Obstrução Uretral/diagnóstico por imagem , Obstrução Uretral/cirurgia
10.
Am J Hum Genet ; 101(1): 123-129, 2017 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-28602422

RESUMO

Megacystis microcolon intestinal hypoperistalsis syndrome (MMIHS) is a congenital disorder characterized by loss of smooth muscle contraction in the bladder and intestine. To date, three genes are known to be involved in MMIHS pathogenesis: ACTG2, MYH11, and LMOD1. However, for approximately 10% of affected individuals, the genetic cause of the disease is unknown, suggesting that other loci are most likely involved. Here, we report on three MMIHS-affected subjects from two consanguineous families with no variants in the known MMIHS-associated genes. By performing homozygosity mapping and whole-exome sequencing, we found homozygous variants in myosin light chain kinase (MYLK) in both families. We identified a 7 bp duplication (c.3838_3844dupGAAAGCG [p.Glu1282_Glyfs∗51]) in one family and a putative splice-site variant (c.3985+5C>A) in the other. Expression studies and splicing assays indicated that both variants affect normal MYLK expression. Because MYLK encodes an important kinase required for myosin activation and subsequent interaction with actin filaments, it is likely that in its absence, contraction of smooth muscle cells is impaired. The existence of a conditional-Mylk-knockout mouse model with severe gut dysmotility and abnormal function of the bladder supports the involvement of this gene in MMIHS pathogenesis. In aggregate, our findings implicate MYLK as a gene involved in the recessive form of MMIHS, confirming that this disease of the visceral organs is heterogeneous with a myopathic origin.


Assuntos
Anormalidades Múltiplas/enzimologia , Anormalidades Múltiplas/genética , Colo/anormalidades , Genes Recessivos , Pseudo-Obstrução Intestinal/enzimologia , Pseudo-Obstrução Intestinal/genética , Mutação/genética , Quinase de Cadeia Leve de Miosina/genética , Bexiga Urinária/anormalidades , Sequência de Bases , Colo/enzimologia , Feminino , Homozigoto , Humanos , Masculino , Linhagem , Bexiga Urinária/enzimologia
11.
Prenat Diagn ; 40(5): 605-611, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32003481

RESUMO

OBJECTIVES: There are many causes of fetal effusions, including the rare lysosomal storage diseases (LSDs). Vacuolated lymphocytes (VLs) are found in the blood of infants with LSDs, and their presence in fetal effusion could increase the risk of underlying LSD. METHODS: Between 2006 and 2018, all fetal effusions samples from 43 fetal multidisciplinary centers were referred to a single laboratory. Cells were counted, and, if observed, VLs were categorized and counted. Screening for LSDs was performed by metabolite analyses on amniotic fluid supernatant. The diagnosis of an LSD was confirmed by measuring the activity of the corresponding enzyme and/or mutation analysis. RESULTS: Our laboratory received 614 ascitic fluids and 280 pleural fluids sampled between 22 and 33 weeks of gestation. The final diagnosis was LSD in 16 cases (1.8%). VLs were reported in all these 16 cases, in a mix of lymphocytes with and without vacuoles. Vacuoles in VLs varied in size and number. In most cases, VLs were easy to recognize, with numerous, large, round, well-defined vacuoles, but in three cases of LSDs, VLs were atypical. CONCLUSION: The finding of VLs in fetal effusions is an inexpensive first-line test that may help to prioritize biochemical and genetic tests for LSDs.


Assuntos
Ascite/patologia , Linfócitos/patologia , Doenças por Armazenamento dos Lisossomos/patologia , Derrame Pleural/patologia , Vacúolos/patologia , Líquido Ascítico/patologia , Feminino , Gangliosidose GM1/diagnóstico , Gangliosidose GM1/patologia , Humanos , Doenças por Armazenamento dos Lisossomos/diagnóstico , Mucolipidoses/diagnóstico , Mucolipidoses/patologia , Mucopolissacaridose VII/diagnóstico , Mucopolissacaridose VII/patologia , Doença de Niemann-Pick Tipo C/diagnóstico , Doença de Niemann-Pick Tipo C/patologia , Gravidez , Diagnóstico Pré-Natal , Sensibilidade e Especificidade , Doença do Armazenamento de Ácido Siálico/diagnóstico , Doença do Armazenamento de Ácido Siálico/patologia
12.
Prenat Diagn ; 40(8): 949-957, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32279384

RESUMO

OBJECTIVES: The objective of this study was to assess whether the laterality of congenital diaphragmatic hernia (CDH) was a prognostic factor for neonatal survival. METHODS: This was a cohort study using the French national database of the Reference Center for Diaphragmatic Hernias. The principal endpoint was survival after hospitalization in intensive care. We made a comparative study between right CDH and left CDH by univariate and multivariate analysis. Terminations and stillbirths were excluded from analyses of neonatal outcomes. RESULTS: A total of 506 CDH were included with 67 (13%) right CDH and 439 left CDH (87%). Rate of survival was 49% for right CDH and 74% for left CDH (P < .01). Multivariate analysis showed two factors significantly associated with mortality: thoracic herniation of liver (OR 2.27; IC 95% [1.07-4.76]; P = .03) and lung-to-head-ratio over under expected (OR 2.99; IC 95% [1.41-6.36]; P < .01). Side of CDH was not significantly associated with mortality (OR 1.87; IC 95% [0.61-5.51], P = .26). CONCLUSION: Rate of right CDH mortality is more important than left CDH. Nevertheless after adjusting for lung-to-head-ratio and thoracic herniation of liver, right CDH does not have a higher risk of mortality than left CDH.


Assuntos
Hérnias Diafragmáticas Congênitas/diagnóstico , Hérnias Diafragmáticas Congênitas/patologia , Pulmão/patologia , Adulto , Estudos de Coortes , Feminino , França/epidemiologia , Hérnias Diafragmáticas Congênitas/mortalidade , Humanos , Lactente , Mortalidade Infantil , Recém-Nascido , Pulmão/diagnóstico por imagem , Masculino , Gravidez , Diagnóstico Pré-Natal , Prognóstico , Reprodutibilidade dos Testes , Estudos Retrospectivos
13.
Neuroimage ; 181: 786-796, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30056198

RESUMO

The most prevalent approach to activation localization in neuroimaging is to identify brain regions as contiguous supra-threshold clusters, check their significance using random field theory, and correct for the multiple clusters being tested. Besides recent criticism on the validity of the random field assumption, a spatial specificity paradox remains: the larger the detected cluster, the less we know about the location of activation within that cluster. This is because cluster inference implies "there exists at least one voxel with an evoked response in the cluster", and not that "all the voxels in the cluster have an evoked response". Inference on voxels within selected clusters is considered bad practice, due to the voxel-wise false positive rate inflation associated with this circular inference. Here, we propose a remedy to the spatial specificity paradox. By applying recent results from the multiple testing statistical literature, we are able to quantify the proportion of truly active voxels within selected clusters, an approach we call All-Resolutions Inference (ARI). If this proportion is high, the paradox vanishes. If it is low, we can further "drill down" from the cluster level to sub-regions, and even to individual voxels, in order to pinpoint the origin of the activation. In fact, ARI allows inference on the proportion of activation in all voxel sets, no matter how large or small, however these have been selected, all from the same data. We use two fMRI datasets to demonstrate the non-triviality of the spatial specificity paradox, and its resolution using ARI. We verify that the endless circularity permitted by ARI does not render its estimates overly conservative using both simulation, and a data split.


Assuntos
Mapeamento Encefálico/métodos , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/fisiologia , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Adulto , Percepção Auditiva/fisiologia , Função Executiva/fisiologia , Humanos
14.
Am J Med Genet A ; 176(11): 2325-2330, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30328679

RESUMO

Trisomy 13 or Patau syndrome (PS) is a well-known aneuploidy characterized by a polymalformative syndrome. We described a large series of fetuses with PS and compared them with cases described in the literature, most of which were live-born. In all, 42 fetuses, aged from 14 to 41 gestational weeks (GW), were examined. The main defects observed were similar to those described in live-born patients: congenital heart defects (76%), holoprosencephaly spectrum anomalies including arhinencephaly and hypotelorism (74%), urinary tract anomalies (71%), ear anomalies (69%), postaxial polydactyly (67%), anogenital anomalies (60%), anophthalmos, and/or microphthalmos (53%), brachycephaly (45%), and oro-facial clefts (45%). A duplication or triplication of at least one distal phalanx of the thumb or hallux was present in 38% of fetuses. This sign has only been reported previously in one patient in the literature. Fetal examination in trisomy 13, is thus, useful to complete the phenotype or to orient diagnosis toward trisomy 13 in the absence of cytogenetic analysis.


Assuntos
Feto/anormalidades , Falanges dos Dedos da Mão/anormalidades , Hallux/anormalidades , Polegar/anormalidades , Falanges dos Dedos do Pé/anormalidades , Síndrome da Trissomia do Cromossomo 13/patologia , Humanos
15.
Pediatr Res ; 84(1): 80-84, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29795201

RESUMO

BACKGROUND: Heme is the prosthetic group of numerous proteins involved in vital processes such as oxygen transport, oxidative stress, and energetic mitochondrial metabolism. Free heme also plays a significant role at early stages of development and in cell differentiation processes. The metabolism of heme by the fetal placenta unit is not well-established in humans. METHODS: In a retrospective study, we measured heme precursors in the amniotic fluid (AF) of 51 healthy women, and 10 AF samples from pregnancies with either upper or lower intestinal atresia or ileus were also analyzed. RESULTS: We showed that the porphyrin precursors aminolevulinic acid, porphobilinogen, and protoporphyrin IX are present at the limit of detection in the AF. Total porphyrin levels decreased progressively from week 13 to week 33 (p < 0.01). Interestingly, uroporphyrin, initially detected as traces, increased with maturation, in contrast to coproporphyrin. Uro- and coproporphyrins were type I immature isomers (>90%), suggesting a lack of maturity in the fetal compartment of the heme pathway. Finally, the differential analysis of AF from normal and pathological pregnancies demonstrated the predominant hepatic origin of fetal porphyrins excreted in the AF. CONCLUSION: This study gives the first insight into heme metabolism in the AF during normal and pathological pregnancies.


Assuntos
Líquido Amniótico/química , Heme/química , Atresia Intestinal/metabolismo , Diagnóstico Pré-Natal/métodos , Adulto , Amniocentese/métodos , Diferenciação Celular , Coproporfirinas/química , Feminino , Humanos , Íleus/patologia , Atresia Intestinal/patologia , Cariotipagem , Idade Materna , Mitocôndrias/metabolismo , Estresse Oxidativo , Oxigênio/metabolismo , Placenta/metabolismo , Porfirias/diagnóstico , Gravidez , Protoporfirinas/química , Estudos Retrospectivos , Uroporfirinas/química
16.
Prenat Diagn ; 2018 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-29752823

RESUMO

OBJECTIVES: The objective of the study is to determine a model of fetal urine biochemical markers to differentiate megacystis microcolon intestinal hypoperistalsis syndrome (MMIHS) from other megacystis. METHOD: This is a retrospective study of biochemical analysis of fetal urine in patients who presented prenatally with megacystis. We studied ß2-microglobulin, sodium, calcium, and phosphorus. Twenty-six patients subsequently diagnosed with MMIHS were compared with 2 control groups: one of end-stage renal failure (64 fetuses) and the second of "good" postnatal renal function (control group, 64 fetuses). RESULTS: Mean fetal urine ß2-microglobulin was significantly higher (P < .001) in end-stage renal failure (15.7 mg/L) than in MMIHS (2.2 mg/L) and the control group (3.2 mg/L). Fetal urine profiles differed significantly (P < .001) between MMIHS and the control group: median sodium 46.5 and 51 mmol/L, median calcium 1.12 and 0.73 mmol/L, and median phosphorus 0.03 and 0.15 mmol/L respectively. Fetal urinary ionic index [ratio: calcium / (phosphorus × sodium)] gave an area under the ROC curve of 0.86, at 54% sensitivity and 97% specificity, with correct classification in 84% of cases. We defined a nomogram to obtain a probability for MMIHS. CONCLUSION: Fetal urinalysis can be helpful in prenatal differentiation of MMIHS from posterior urethral valves with good postnatal renal function.

17.
Prenat Diagn ; 2018 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-29644715

RESUMO

OBJECTIVES: To compare the prognostic value of fetal serum biochemistry and fetal urine biochemistry in predicting renal outcome in lower urinary tract obstruction (LUTO). METHODS: We retrospectively studied renal outcome following a prenatal diagnosis of LUTO in cases for which both fetal blood and fetal urine were sampled. We classified the renal outcome as either "favorable," when postnatal renal function was normal, or "adverse," in the case of postnatal chronic renal failure or when renal histological lesions were present at autopsy in the case of termination of pregnancy. A prognostic model was constructed for urine and serum separately. ß2-Microglobulin was the only remaining independent predictor in fetal urine. ß2-Microglobulin in serum and urine were compared by using receiver operating characteristic curves. RESULTS: In the 50 cases included, the rate of adverse outcome was 34 of 50(68%): autopsy confirmed severity of renal disease in all 27 cases who underwent termination of pregnancy, and among the 23 live born children, 7 developed renal failure. Fetal serum and urine markers were all significantly associated with renal outcome (P < .01). The receiver operating characteristic curves for fetal serum and fetal urinary ß2-microglobulin were similar (area under the curve = 0.908 versus 0.909, P = .96). CONCLUSION: Fetal serum biochemistry and fetal urine biochemistry are of similar prognostic value in predicting postnatal renal outcome in fetuses with LUTO.

18.
Prenat Diagn ; 38(12): 964-970, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30207389

RESUMO

OBJECTIVE: Because the literature on the predictive value of fetal urinalysis is controversial in fetuses with lower urinary tract obstruction, we determined the best model of fetal urine biochemical markers correlated with long-term postnatal renal function based on glomerular filtration rate (GFR). METHOD: This retrospective study concerned 89 fetuses with lower urinary tract obstruction and their renal function after 10 years of age. We correlated fetal urine biochemical markers (total protein, ß2-microglobulin, sodium, chloride, glucose, calcium, and phosphorus) with GFR at 10 to 30 years of age in 89 patients with posterior urethral valves. We defined five stages of chronic kidney disease (CKD). RESULTS: Of the 89 patients, 18 (20%) are 20 years old or over. Postnatal renal function was good in 67.4% (GFR > 60 mL/min/1.73 m2 ) and poor in 17% (GFR < 30 mL/min/1.73 m2 ). All fetal urine markers differed between CKD stage 1 + 2 and CKD stage 4 + 5 (P < 0.001). ß2-microblobulin showed an 87% sensitivity for a 72% specificity. A combination of ß2-microglobulin and chloride gave the best results (93% sensitivity and 71% specificity) versus amniotic fluid volume (80% sensitivity and 73% specificity). CONCLUSION: Fetal urine biochemistry predicts long-term (10-30 years) postnatal renal function.


Assuntos
Doenças Fetais/urina , Insuficiência Renal Crônica/fisiopatologia , Insuficiência Renal Crônica/urina , Obstrução Uretral/urina , Microglobulina beta-2/urina , Biomarcadores/urina , Criança , Cloretos/urina , Feminino , Doenças Fetais/diagnóstico por imagem , Doenças Fetais/etiologia , Taxa de Filtração Glomerular , Humanos , Masculino , Oligo-Hidrâmnio/diagnóstico por imagem , Oligo-Hidrâmnio/etiologia , Valor Preditivo dos Testes , Gravidez , Prognóstico , Insuficiência Renal Crônica/congênito , Insuficiência Renal Crônica/etiologia , Estudos Retrospectivos , Obstrução Uretral/congênito , Obstrução Uretral/diagnóstico por imagem , Obstrução Uretral/etiologia , Urinálise
19.
Fetal Pediatr Pathol ; 37(6): 433-447, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30636554

RESUMO

INTRODUCTION: Ablation of the acardiac twin umbilical cord in the TRAP protects the normal donor twin. MATERIALS AND METHODS: Two case descriptions, one of interstitial laser photocoagulation and one of laser umbilical cord occlusion (L-UCO) of the acardiac twin in monochorionic monoamniotic pregnancies are reported. RESULTS: L-UCO in two pregnancies with TRAP syndrome in the second trimester resulted in intrauterine fetal death in both cases after 1 month. Case 1 had no detectable cause of fetal death. Case 2 had rupture of the amniotic sac causing anhydramnios and acute chorioamnionitis. A groove on the umbilical cord of the normal twin indicated a cord stricture due to cord entanglement. CONCLUSION: Our experience confirms that the best timing and optimal treatment of MC/MA twins complicated by TRAP sequence still remains a controversial clinical issue. Cord entanglement may continue be a potential clinical risk factor for adverse perinatal outcome even after ablation therapy.


Assuntos
Transfusão Feto-Fetal/cirurgia , Fetoscopia/métodos , Fotocoagulação a Laser/métodos , Terapia a Laser/métodos , Feminino , Humanos , Gravidez , Gêmeos Monozigóticos
20.
Neuroimage ; 146: 113-120, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-27851996

RESUMO

Multivoxel pattern analysis (MVPA) has gained enormous popularity in the neuroimaging community over the past few years. At the group level, most MVPA studies adopt an "information based" approach in which the sign of the effect of individual subjects is discarded and a non-directional summary statistic is carried over to the second level. This is in contrast to a directional "activation based" approach typical in univariate group level analysis, in which both signal magnitude and sign are taken into account. The transition from examining effects in one voxel at a time vs. several voxels (univariate vs. multivariate) has thus tacitly entailed a transition from directional to non-directional signal definition at the group level. While a directional group-level MVPA approach implies that individuals have similar multivariate spatial patterns of activity, in a non-directional approach each individual may have a distinct spatial pattern. Using an experimental dataset, we show that directional and non-directional group-level MVPA approaches uncover distinct brain regions with only partial overlap. We propose a method to quantify the degree of spatial similarity in activation patterns over subjects. Applied to an auditory task, we find higher values in auditory regions compared to control regions.


Assuntos
Mapeamento Encefálico , Encéfalo/anatomia & histologia , Encéfalo/fisiologia , Imageamento por Ressonância Magnética , Humanos , Processamento de Imagem Assistida por Computador , Análise Multivariada , Processamento de Sinais Assistido por Computador
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