Publications by authors named "Robert Cabrera"

Folic acid (FA) is well known to prevent neural tube defects (NTDs), but we do not know why many human NTD cases still remain refractory to FA supplementation. Here, we investigate how the DNA demethylase TET1 interacts with maternal FA status to regulate mouse embryonic brain development. We determined that cranial NTDs display higher penetrance in non-inbred than in inbred Tet1 embryos and are resistant to FA supplementation across strains.

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The etiology of neural tube defects (NTDs) involves complex gene-environmental interactions. Folic acid (FA) prevents NTDs, but the mechanisms remain poorly understood and at least 30% of human NTDs resist the beneficial effects of FA supplementation. Here, we identify the DNA demethylase TET1 as a nexus of folate-dependent one-carbon metabolism and genetic risk factors post-neural tube closure.

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During the first month of pregnancy, the brain and spinal cord are formed through a process called neurulation. However, this process can be altered by low serum levels of folic acid, environmental factors, or genetic predispositions. In 2018, a surveillance study in Botswana, a country with a high incidence of human immunodeficiency virus (HIV) and lacking mandatory food folate fortification programs, found that newborns whose mothers were taking dolutegravir (DTG) during the first trimester of pregnancy had an increased risk of neural tube defects (NTDs).

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Folate deficiency contribute to neural tube defects (NTDs) which could be rescued by folate supplementation. However, the underlying mechanisms are still not fully understood. Besides, there is considerable controversy concerning the forms of folate used for supplementation.

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Objectives: In 2018, the Botswana Tsepamo Study reported a nine-fold increased risk of neural tube defects in infants whose mothers were treated with dolutegravir (DTG) from the time of conception. As maternal folate supplementation and status is a well known modifier of neural tube defect (NTD) risk, we sought to evaluate birth outcomes in mice fed normal and low folic acid diets treated with DTG during pregnancy.

Design: DTG was evaluated for developmental toxicity using pregnant mice fed normal or low folic acid diet.

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Unlabelled: Folates are B vitamins that are essential for several molecular, cellular, and biological processes, including nucleotide synthesis, methylation, and methionine cycling. The physiological impacts of these processes on health also extend to cell proliferation, folate deficiency anemia, and reduction of the risk of birth defects during pregnancy. The primary objective of this study was to characterize the binding affinities of different folate forms, folic acid (FA), 5-methyltetrahydrofolate (5MTHF), and folinic acid, to the folate receptors α and β, and to the bovine milk folate binding protein.

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Article Synopsis
  • - The study investigates the genetic causes of cerebral folate deficiency (CFD) by analyzing exome sequencing results from 48 patients to identify potential variants associated with the condition.
  • - Researchers found six variants in five patients, impacting the KDM6B protein and leading to changes in histone modifications and reduced FOLR1 protein levels, which are critical for folate transport.
  • - The findings suggest that the identified gene may be a new candidate linked to CFD, potentially lowering FOLR1 expression and increasing the risk for developing FOLR1 autoantibodies in affected individuals.
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Neural tube defects (NTDs) are congenital malformations resulting from abnormal embryonic development of the brain, spine, or spinal column. The genetic etiology of human NTDs remains poorly understood despite intensive investigation. CIC, homolog of the Capicua transcription repressor, has been reported to interact with ataxin-1 (ATXN1) and participate in the pathogenesis of spinocerebellar ataxia type 1.

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Valproic acid (VPA, valproate, Depakote) is a commonly used anti-seizure medication (ASM) in the treatment of epilepsy and a variety of other neurological disorders. While VPA and other ASMs are efficacious for management of seizures, they also increase the risk for adverse pregnancy outcomes, including neural tube defects (NTDs). Thus, the utility of these drugs during pregnancy and in women of childbearing potential presents a continuing public health challenge.

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Human structural congenital malformations are the leading cause of infant mortality in the United States. Estimates from the United States Center for Disease Control and Prevention (CDC) determine that close to 3% of all United States newborns present with birth defects; the worldwide estimate approaches 6% of infants presenting with congenital anomalies. The scientific community has recognized for decades that the majority of birth defects have undetermined etiologies, although we propose that environmental agents interacting with inherited susceptibility genes are the major contributing factors.

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Neural tube defects (NTDs) are a group of common and severe congenital malformations. The PI3K-AKT signalling pathway plays a crucial role in the neural tube development. There is limited evidence concerning any possible association between aberrant methylation in PI3K-AKT signalling pathway genes and NTDs.

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Neural tube defects (NTDs) are a group of severe congenital malformations caused by a failure of neural tube closure during early embryonic development. Although extensively investigated, the genetic etiology of NTDs remains poorly understood. FKBP8 is critical for proper mammalian neural tube closure.

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Cerebral folate deficiency (CFD) syndrome is characterised by a low concentration of 5-methyltetrahydrofolate in cerebrospinal fluid, while folate levels in plasma and red blood cells are in the low normal range. Mutations in several folate pathway genes, including , , and ) have been previously identified in patients with CFD. In an effort to identify causal mutations for CFD, we performed whole exome sequencing analysis on eight CFD trios and identified eight de novo mutations in seven trios.

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Every year nearly 6 percent of children worldwide are born with a serious congenital malformation, resulting in death or lifelong disability. In the United States, birth defects remain one of the leading causes of infant mortality. Among the common structural congenital defects are conditions known as neural tube defects (NTDs).

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Article Synopsis
  • - SSRIs, like paroxetine and sertraline, are commonly prescribed to pregnant women, but there's ongoing debate about their developmental risks.
  • - Ethical concerns prevent studies on pregnant women, so researchers conducted a study using mice to assess the effects of sertraline during pregnancy.
  • - The study found that higher doses of sertraline led to increased fetal abnormalities and lower fetal weights, with significant issues like cleft palate occurring in exposed fetuses, indicating that sertraline can be harmful during fetal development.
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Background: Tributyltin (TBT) is a persistent and bioaccumulative environmental toxicant. Developmental exposure to TBT has been shown to cause fatty liver disease (steatosis), as well as increased adiposity in many species, leading to its characterization as an obesogen.

Objective: We aimed to determine the long-term effects of developmental TBT exposure on the liver.

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DNA damage response (DDR) genes orchestrating the network of DNA repair, cell cycle control, are essential for the rapid proliferation of neural progenitor cells. To date, the potential association between specific DDR genes and the risk of human neural tube defects (NTDs) has not been investigated. Using whole-genome sequencing and targeted sequencing, we identified significant enrichment of rare deleterious RAD9B variants in spina bifida cases compared to controls (8/409 vs.

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Background/purpose: In 2004, a heritable occurrence of spina bifida was reported in sheep on a farm in the United States. We maintained and characterized the spina bifida phenotype in this flock to assess its potential as an alternative surgical model.

Methods: A breeding strategy was developed in which the sheep were crossed to maintain or increase the occurrence of spina bifida.

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Objective: Maternal folate (vitamin B9) status is the largest known modifier of neural tube defect risk, so we evaluated folate-related mechanisms of action for dolutegravir (DTG) developmental toxicity.

Design: Folate receptor 1 (FOLR1) was examined as a target for DTG developmental toxicity using protein and cellular interaction studies and an animal model.

Methods: FOLR1 competitive binding studies were used to test DTG for FOLR1 antagonism.

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Objectives: The anticonvulsant valproic acid (VPA) has a known teratogenic effect capable of inducing major congenital malformations and developmental disorders. A comparative teratogenicity study of VPA and its analog valnoctamide (VCD), which is a new generation candidate antiepileptic drug, was carried out using Swiss Vancouver (SWV) mice.

Methods: Pregnant SWV dams were treated with either a single intraperitoneal injection of VPA (1.

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The assays in this study utilize mouse embryonic stem cells (mESCs) and zebrafish embryos to evaluate the potential developmental toxicity of industrial and pharmaceutical chemicals. A set of eleven chemicals of known mammalian in vivo teratogenicity were tested in the assays and correlations to mammalian data. Using mESCs, proliferation, differentiation, and cytotoxicity of the chemicals were measured.

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Background: Folate receptors (FRs) facilitate embryonic uptake of folates and are important for proper early embryonic development. There is accumulating evidence that blocking FR autoantibodies contribute to developmental diseases. However, genetic factors associated with the expression of FR autoantibodies remain unknown.

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