Neural Tube Research Articles

Teratogenesis, Perinatal, and Neurodevelopmental Outcomes After In Utero Exposure to Antiseizure Medication: Practice Guideline From the AAN, AES, and SMFM.

This practice guideline provides updated evidence-based conclusions and recommendations regarding the effects of antiseizure medications (ASMs) and folic acid supplementation on the prevalence of major congenital malformations (MCMs), adverse perinatal outcomes, and neurodevelopmental outcomes in children born to people with epilepsy of childbearing potential (PWECP). A multidisciplinary panel conducted a systematic review and developed practice recommendations following the process outlined in the 2017 edition of the American Academy of Neurology Clinical Practice Guideline Process Manual. The systematic review includes studies through August 2022. Recommendations are supported by structured rationales that integrate evidence from the systematic review, related evidence, principles of care, and inferences from evidence. The following are some of the major recommendations. When treating PWECP, clinicians should recommend ASMs and doses that optimize both seizure control and fetal outcomes should pregnancy occur, at the earliest possible opportunity preconceptionally. Clinicians must minimize the occurrence of convulsive seizures in PWECP during pregnancy to minimize potential risks to the birth parent and to the fetus. Once a PWECP is already pregnant, clinicians should exercise caution in attempting to remove or replace an ASM that is effective in controlling generalized tonic-clonic or focal-to-bilateral tonic-clonic seizures. Clinicians must consider using lamotrigine, levetiracetam, or oxcarbazepine in PWECP when appropriate based on the patient's epilepsy syndrome, likelihood of achieving seizure control, and comorbidities, to minimize the risk of MCMs. Clinicians must avoid the use of valproic acid in PWECP to minimize the risk of MCMs or neural tube defects (NTDs), if clinically feasible. Clinicians should avoid the use of valproic acid or topiramate in PWECP to minimize the risk of offspring being born small for gestational age, if clinically feasible. To reduce the risk of poor neurodevelopmental outcomes, including autism spectrum disorder and lower IQ, in children born to PWECP, clinicians must avoid the use of valproic acid in PWECP, if clinically feasible. Clinicians should prescribe at least 0.4 mg of folic acid supplementation daily preconceptionally and during pregnancy to any PWECP treated with an ASM to decrease the risk of NTDs and possibly improve neurodevelopmental outcomes in the offspring.

Single cell RNA-sequencing and RNA-tomography of the avian embryo extending body axis

Introduction: Vertebrate body axis formation initiates during gastrulation and continues within the tail bud at the posterior end of the embryo. Major structures in the trunk are paired somites, which generate the musculoskeletal system, the spinal cord—forming part of the central nervous system, and the notochord, with important patterning functions. The specification of these different cell lineages by key signalling pathways and transcription factors is essential, however, a global map of cell types and expressed genes in the avian trunk is missing.Methods: Here we use high-throughput sequencing approaches to generate a molecular map of the emerging trunk and tailbud in the chick embryo.Results and Discussion: Single cell RNA-sequencing (scRNA-seq) identifies discrete cell lineages including somites, neural tube, neural crest, lateral plate mesoderm, ectoderm, endothelial and blood progenitors. In addition, RNA-seq of sequential tissue sections (RNA-tomography) provides a spatially resolved, genome-wide expression dataset for the avian tailbud and emerging body, comparable to other model systems. Combining the single cell and RNA-tomography datasets, we identify spatially restricted genes, focusing on somites and early myoblasts. Thus, this high-resolution transcriptome map incorporating cell types in the embryonic trunk can expose molecular pathways involved in body axis development.

A global gene regulatory program and its region-specific regulator partition neurons into commissural and ipsilateral projection types.

Understanding the genetic programs that drive neuronal diversification into classes and subclasses is key to understand nervous system development. All neurons can be classified into two types: commissural and ipsilateral, based on whether their axons cross the midline or not. However, the gene regulatory program underlying this binary division is poorly understood. We identified a pair of basic helix-loop-helix transcription factors, Nhlh1 and Nhlh2, as a global transcriptional mechanism that controls the laterality of all floor plate-crossing commissural axons in mice. Mechanistically, Nhlh1/2 play an essential role in the expression of Robo3, the key guidance molecule for commissural axon projections. This genetic program appears to be evolutionarily conserved in chick. We further discovered that Isl1, primarily expressed in ipsilateral neurons within neural tubes, negatively regulates the Robo3 induction by Nhlh1/2. Our findings elucidate a gene regulatory strategy where a conserved global mechanism intersects with neuron class-specific regulators to control the partitioning of neurons based on axon laterality.

Folic Acid Supplementation to Prevent Neural Tube Defects Updated Evidence Report and Systematic Review for the US Preventive Services Task Force

(JAMA. 2023;330(5):460–466) Neural tube defects are among the most commonly recorded birth defects for babies in the United States, and they are typically caused by low folate concentrations during conception and early gestation. These malformations can cause disabilities and even death in fetuses and children. In 2017, the United States Preventative Services Task Force (USPSTF) determined that women who increase their intake of folic acid before becoming pregnant can significantly help reduce the likelihood of their babies developing neural tube defects. The USPSTF also asserted their 2009 recommendation that patients should take 0.4 to 0.8 mg (400 to 800 μg) of folic acid daily if they were planning or capable of pregnancy, and that there was no consistent strong evidence of harmful adverse effects. This evidence report was conducted to analyze studies post-2017 for the USPSTF’s current recommendation on folic acid supplementation.

#2289 Pregnancy outcomes in patients with congenital abnormality of the urinary tract: experience of a tertiary Portuguese center

Abstract Background and Aims Congenital abnormalities of the urinary tract (CAKUT) represent a broad range of disorders that occur due to abnormal kidney development. Maternal, obstetric, and perinatal outcome in pregnant woman with CAKUT have not been extensively evaluated, although small series report an increased incidence of urinary tract infections (UTI) and obstructive uropathy. Method Retrospective analysis of maternal, obstetric, and perinatal outcomes in pregnant patients with CAKUT (including genetic cystic kidney disease) that were surveilled in our tertiary center by a nephro-obstetric team between 2011 and June 2023. Information was obtained from medical records. Results We evaluated 47 gestations in 41 patients, with mean age of 31 ± 5 years [17-40], 89% were Caucasian, 11% black; 40% were nulliparous, 36% had hypertension (HT) and 42% a previous history of UTI. Regarding CAKUT specificity, 17/41 patients had genetic cystic diseases, 10/41 ureteropelvic junction obstruction (UPJ), 4/41 duplicate collecting system, 5/41 vesicourethral reflux, 2/41 ectopic kidney, 3/41 renal hypoplasia. Genetic testing was done before, during or after pregnancy in 2/4/4 patients, respectively. Teratogenic therapy exposure occurred in 25% of gestations. Most patients were CKD stage 1 (33/41), with 2/4/1/1 with patients in CKD stage 2/3/4/5, respectively. Mean baseline SCr was 0.99 ± 0.8 mg/dL [0.4-4.6] and mean proteinuria was 194 ± 357 mg/g [22-1500]. Renal function (RF) deterioration occurred in 9/47 (19%) women due to pre-eclampsia (PE), pregnancy hyperfiltration (PH) and hydronephrosis in 3/3/3 patients, respectively. Urologic intervention was needed in 2 patients due to hydronephrosis, and one of the patients required transient dialysis. All patients fully recovered RF except for the 1 CKD stage 3 patients that had partial RF recovery. De novo and worsening proteinuria occurred in 7/47 gestations due to PE (3/7) and PH (4/7). De novo or aggravation of HTN occurred in 25% gestations, UTI in 19% and PE in 6% gestations. Regarding fetal outcomes, mean duration of gestation was 38 ± 2 weeks [32-41] and mean birth weight 2910 ± 634 g [1360-4600]. There was 1 miscarriage and 1 medical termination of pregnancy at 17 weeks (neural tube defect). Cesarean was performed in (8/47, 17%) gestations and 10/47 (17%) newborns were admitted to the neonatal care unit (NICU) mainly due to prematurity, sepsis and feeding intolerance. Conclusion Our cohort of CAKUT patients was very heterogenous and only 19.5% had CKD stage 2-5. Still, we found a significant incidence of maternal, obstetric, and perinatal complications, namely HT UTI, PE, and the need for NICU. UPJ obstruction can evolve with RF deterioration and the need for intervention during pregnancy. This study underlines the importance of the management of these patients by a multidisciplinary team.

Patterns and short term neurosurgical treatment outcomes of neonates with neural tube defects admitted to Felege Hiwot Specialized Hospital, Bahir Dar, Ethiopia

BackgroundNeural tube defects (NTDs) account for the largest proportion of congenital anomalies of the central nervous system and result from failure of the neural tube to close spontaneously between the 3rd and 4th weeks of in utero development. Prognosis and treatment outcome depends on the nature and the pattern of the defect. The nature of treatment outcomes and its pattern associated with grave prognosis is not well known in the study area.ObjectiveThe aim of study was to determine the patterns and short term neurosurgical management outcomes of newborns with neural tube defects admitted at Felege Hiwot Specialized Hospital.MethodsInstitutional based retrospective cross-sectional study among neonates, who were admitted at Felege Hiwot Specialized Hospital with neural tube defects from January 1st to December, 30th, 2018 was conducted. All Charts of Neonates with confirmed diagnosis of neural tube defects were included as part of the study. Trained data collectors (medical interns) supervised by trained supervisors (general practitioners) collected the data using a pretested data extraction format. Data were coded, entered and analyzed using SPSS version 23 software. Frequency and cross tabulations were used to summarize descriptive statistics of data, and tables and graphs were used for data presentation.ResultAbout 109 patients had complete documentation and imaging confirmed neural tube defects. Myelomeningocele was the commonest pattern 70 (64.2%). Thoracolumbar spine was the commonest site of presentation 49(45%). The most common associated impairment was hydrocephalus 37(33.9%). Forty-five (41.1%) had multiple complications. The mortality rate was 7.3%, 44% were discharged with sequalae and 36.7% were discharged without impairment. The significant causes of death were infection 66.7% and Chiari crisis 33.3%.ConclusionMyelomeningocele was the most frequent clinical pattern of neural tube defect and thoracolumbar spine was the commonest site. Isolated neural tube defect was the commonest finding. There were multiple complications after surgery accompanied with meningitis and hydrocephalus. The mortality rate among neonates with neural tube defects was considerably high. The commonest causes of death were infection and Chiari crisis.

Pin1 Downregulation Is Involved in Excess Retinoic Acid-Induced Failure of Neural Tube Closure

Neural tube defects (NTDs), which are caused by impaired embryonic neural tube closure, are one of the most serious and common birth defects. Peptidyl-prolyl cis/trans isomerase 1 (Pin1) is a prolyl isomerase that uniquely regulates cell signaling by manipulating protein conformation following phosphorylation, although its involvement in neuronal development remains unknown. In this study, we explored the involvement of Pin1 in NTDs and its potential mechanisms both in vitro and in vivo. The levels of Pin1 expression were reduced in NTD models induced by all-trans retinoic acid (Atra). Pin1 plays a significant role in regulating the apoptosis, proliferation, differentiation, and migration of neurons. Moreover, Pin1 knockdown significantly was found to exacerbate oxidative stress (OS) and endoplasmic reticulum stress (ERs) in neuronal cells. Further studies showed that the Notch1-Nrf2 signaling pathway may participate in Pin1 regulation of NTDs, as evidenced by the inhibition and overexpression of the Notch1-Nrf2 pathway. In addition, immunofluorescence (IF), co-immunoprecipitation (Co-IP), and GST pull-down experiments also showed that Pin1 interacts directly with Notch1 and Nrf2. Thus, our study suggested that the knocking down of Pin1 promotes NTD progression by inhibiting the activation of the Notch1-Nrf2 signaling pathway, and it is possible that this effect is achieved by disrupting the interaction of Pin1 with Notch1 and Nrf2, affecting their proteostasis. Our research identified that the regulation of Pin1 by retinoic acid (RA) and its involvement in the development of NTDs through the Notch1-Nrf2 axis could enhance our comprehension of the mechanism behind RA-induced brain abnormalities.

Activation of lipophagy ameliorates cadmium-induced neural tube defects via reducing low density lipoprotein cholesterol levels in mouse placentas

Neural tube defects (NTDs) represent a prevalent and severe category of congenital anomalies in humans. Cadmium (Cd) is an environmental teratogen known to cause fetal NTDs. However, its underlying mechanisms remain elusive. This study aims to investigate the therapeutic potential of lipophagy in the treatment of NTDs, providing valuable insights for future strategies targeting lipophagy activation as a means to mitigate NTDs.We successfully modeled NTDs by Cd exposure during pregnancy. RNA sequencing was employed to investigate the transcriptomic alterations and functional enrichment of differentially expressed genes in NTD placental tissues. Subsequently, pharmacological/genetic (Atg5-/- placentas) experiments confirmed that inducing placental lipophagy can alleviate Cd induced-NTDs. We found that Cd exposure caused NTDs. Further analyzed transcriptomic data from the placentas with NTDs which revealed significant downregulation of low-density lipoprotein receptor associated protein 1(Lrp1) gene expression responsible for positive regulation of low-density lipoprotein cholesterol (LDL-C) transport. Correspondingly, there was an increase in maternal serum/placenta/amniotic fluid LDL-C content. Subsequently, we have discovered that Cd exposure activated placental lipophagy. Pharmacological/genetic (Atg5-/- placentas) experiments confirmed that inducing placental lipophagy can alleviate Cd induced-NTDs. Furthermore, our findings demonstrate that activation of placental lipophagy effectively counteracts the Cd-induced elevation in LDL-C levels. Lipophagy serves to mitigate Cd-induced NTDs by reducing LDL-C levels within mouse placentas.

A journey in the world of craniofacial development: From 1968 to the future.

This article is based on my talk at the meeting "3rd Advances in Craniosynostosis: Basic Science to Clinical Practice", held at University College, London, on 25 August 2023. It describes my contribution, together with that of my research team and external collaborators, to the field of craniofacial development. This began with my PhD research on the effects of excess vitamin A in rat embryos, which led to a study of normal as well as abnormal formation of the cranial neural tube. Many techniques for analysing morphogenetic change became available to me over the years: whole embryo culture, scanning and transmission electron microscopy, cell division analysis, immunohistochemistry and biochemical analysis of the extracellular matrix. The molecular revolution of the 1980s, and key collaborations with international research teams, enabled functional interpretation of some of the earlier morphological observations and required a change of experimental species to the mouse. Interactions between the molecular and experimental analysis of craniofacial morphogenesis in my laboratory with specialists in molecular genetics and clinicians brought my research journey near to my original aim: to contribute to a better understanding of the causes of human congenital anomalies.

Dolutegravir induces FOLR1 expression during brain organoid development

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). As a result, the World Health Organization and the U.S. Food and Drug Administration have issued guidelines emphasizing the potential risks associated with the use of DTG-based antiretroviral therapies during pregnancy. To elucidate the potential mechanisms underlying the DTG-induced NTDs, we sought to assess the potential neurotoxicity of DTG in stem cell-derived brain organoids. The gene expression of brain organoids developed in the presence of DTG was analyzed by RNA sequencing, Optical Coherence Tomography (OCT), Optical Coherence Elastography (OCE), and Brillouin microscopy. The sequencing data shows that DTG induces the expression of the folate receptor (FOLR1) and modifies the expression of genes required for neurogenesis. The Brillouin frequency shift observed at the surface of DTG-exposed brain organoids indicates an increase in superficial tissue stiffness. In contrast, reverberant OCE measurements indicate decreased organoid volumes and internal stiffness.

Paediatric hydrocephalus.

Hydrocephalus is classically considered as a failure of cerebrospinal fluid (CSF) homeostasis that results in the active expansion of the cerebral ventricles. Infants with hydrocephalus can present with progressive increases in head circumference whereas older children often present with signs and symptoms of elevated intracranial pressure. Congenital hydrocephalus is present at or near birth and some cases have been linked to gene mutations that disrupt brain morphogenesis and alter the biomechanics of the CSF-brain interface. Acquired hydrocephalus can develop at any time after birth, is often caused by central nervous system infection or haemorrhage and has been associated with blockage of CSF pathways and inflammation-dependent dysregulation of CSF secretion and clearance. Treatments for hydrocephalus mainly include surgical CSF shunting or endoscopic third ventriculostomy with or without choroid plexus cauterization. In utero treatment of fetal hydrocephalus is possible via surgical closure of associated neural tube defects. Long-term outcomes for children with hydrocephalus vary widely and depend on intrinsic (genetic) and extrinsic factors. Advances in genomics, brain imaging and other technologies are beginning to refine the definition of hydrocephalus, increase precision of prognostication and identify nonsurgical treatment strategies.

The sequence of acrania–exencephaly–anencephaly (AEAS)- An infrequent case report

Acrania–exencephaly–anencephaly sequence has an incidence of 3.6–5.4 for 10,000 live births and has been reported in literature. Exencephaly, described here is a defect of the neural tube which occurs due to the absence of closure of the neural fold. The main diagnostic ultrasound features include that are characterized by acrania, decreased size of cranial pole in comparison with the chest, irregular cranial surface, with increased amniotic fluid echogenicity due to the damaged brain tissue. Associated with amniotic band syndrome, Pentalogy of Cantrell, limb anomalies and ventral body wall defects. It is incompatible with life. Conducting programs training the budding neuro-sonographers about the knowledge in detection, diagnosis of NTD according to the Carnegie Classification is crucial to look forward in pathogenesis and application in the clinical scenario.

Forced LMX1A expression induces dorsal neural fates and disrupts patterning of human embryonic stem cells into ventral midbrain dopaminergic neurons.

The differentiation of human pluripotent stem cells into ventral mesencephalic dopaminergic (DA) fate is relevant for the treatment of Parkinson's disease. Shortcuts to obtaining DA cells through direct reprogramming often include forced expression of the transcription factor LMX1A. Although reprogramming with LMX1A can generate tyrosine hydroxylase (TH)-positive cells, their regional identity remains elusive. Using an invitro model of early human neural tube patterning, we report that forced LMX1A expression induced a ventral-to-dorsal fate shift along the entire neuroaxis with the emergence of roof plate fates despite the presence of ventralizing molecules. The LMX1A-expressing progenitors gave rise to grafts containing roof plate-derived choroid plexus cysts as well as ectopically induced TH-positive neurons of a forebrain identity. Early activation of LMX1A prior to floor plate specification was necessary for the dorsalizing effect. Our work suggests using caution in employing LMX1A for the induction of DA fate, as this factor may generate roof plate rather than midbrain fates.

Introduction: A Practical Guide to Central Nervous System Malformations—From Genetics, to Diagnosis and Treatment

AbstractCentral nervous system (CNS) malformations encompass diverse congenital anomalies impacting brain and spinal cord development, profoundly affecting neurological function. They arise from disruptions in embryonic neural tube formation, neuronal migration, and cortical organization. This abstract provides a comprehensive overview of CNS malformations, covering classification, etiology, clinical manifestations, and diagnostic challenges. CNS malformations fall into distinct groups: neural tube defects (e.g., anencephaly, spina bifida), resulting from incomplete neural tube closure; malformations of cortical development (e.g., lissencephaly, polymicrogyria), featuring irregularities in cortical folding; and anomalies affecting structures like the corpus callosum, cerebellum, and CNS vasculature, alongside conditions such as hydrocephalus and Chiari malformations. Genetic factors, including mutations in LIS1, DCX, and RELN, contribute significantly, while environmental factors like maternal folic acid deficiency also play a role. Some malformations occur in genetic syndromes (e.g., tuberous sclerosis, neurofibromatosis). Clinical presentations vary, with neural tube defects typically presenting severe deficits at birth, while cortical malformations manifest as intellectual disabilities, seizures, and motor deficits. Hydrocephalus elevates intracranial pressure, and Chiari malformations cause headaches and neurological symptoms. Diagnosis necessitates a multidisciplinary approach involving clinical evaluation, neuroimaging, genetic testing, and histopathological analysis. Prenatal diagnosis via ultrasound and magnetic resonance imaging is crucial for planning interventions, while postnatal diagnosis relies on clinical and imaging findings.Understanding CNS malformations is vital for early detection, intervention, and comprehensive care provision. Advances in genetics and neuroimaging offer hope for improved outcomes and better quality of life for affected individuals.

Anomalies of the Mesenchyme (Meninges and Skull)—Defects of Neural Tube Closure: Cephalocele and Other Calvarial and Skull Base Defects; Intracranial Lipomas; Arachnoid Cysts; Nonsyndromic and Syndromic Craniosynostoses

AbstractWithin the embryonic head, a layer of mesenchyme envelops the brain beneath the surface ectoderm. This cranial mesenchyme is responsible for the formation of the meninges, the calvaria (upper portion of the skull), and the scalp's dermis. Irregular development of these structures, particularly the meninges and the calvaria, is associated with notable congenital defects in humans, such as defects in neural tube closure. Anencephaly is the most common neural tube defect (NTD) and one of the most severe malformations of the central nervous system; it consists in the complete or partial absence of the brain, associated with the absence of the bones of the cranial vault. Iniencephaly is an uncommon congenital NTD characterized by abnormalities in the occipital region, including rachischisis of the cervicothoracic spine and a fixed retroflexion deformity of the head. Unlike anencephaly, in iniencephaly, there is a skull cavity and a normal-looking skin that entirely covers the head and the medullary retroflex area. Cephaloceles are congenital abnormalities distinguished by the protrusion of meninges and/or brain tissue through a naturally occurring defect in the skull bone. This anomaly is typically covered by skin or mucous membrane. Intracranial lipoma is a relatively uncommon and generally benign tumor that occurs in an abnormal location within the brain; it probably represents a disturbance of the differentiation of the primordial meninges: for unknown causes, the meningeal mesenchyme can differentiate into adipose tissue. Arachnoid cysts are sacs filled with cerebrospinal fluid (CSF) situated between the brain or spinal cord and the arachnoid membrane. Typically, these cysts originate within CSF cisterns and gradually expand their boundaries. Craniosynostosis is the early fusion of one or more cranial sutures. It can occur spontaneously, be associated with a syndrome, or have a familial connection. It can involve one or multiple cranial sutures. Pfeiffer's, Crouzon's, and Apert's syndromes are among the more prevalent syndromic craniosynostoses.

The concept of folic acid supplementation and its role in prevention of neural tube defect among pregnant women: PRISMA.

Folic acid is the synthetic form of vitamin B9, found in supplements and fortified foods, while folate occurs naturally in foods. Folic acid and its derivatives are extremely important in the synthesis of nucleic acids (DNA and ribose nucleic acid [RNA]) and different proteins. It acts as a coenzyme for the transfer of 1 carbon in the biosynthesis of purine, pyrimidine, and amino acids. Folic acid is critically important in rapidly proliferating tissues, including fetus and trophoblastic tissue to prevent neural tube defect (NTD). The main objective of this review is to identify the role of folic acid to prevent NTD among pregnancy mothers. Electronic databases including Web of Science, Google Scholar, MEDLINE, Scopus, and Cochrane library used to systematically search without limitation of publication date and status. In pregnancy, the first trimester is a significant time for neural tube closure. Decreased blood folic acid levels inhibit DNA replication, repair, RNA synthesis, histone and DNA methylation, methionine production, and homocysteine remethylation reactions that cause NTDs in pregnancy. Therefore, folic acid supplementation is critically important for childbearing mothers before conception and in the first trimester pregnancy. As a result, women are recommended to take 400 microgram FA/day from preconception until the end of the first trimester to prevent NTD-affected pregnancies. This allows the developing neural tissue to acquire critical mass and provides the preferred rostrocaudal orientation so that these divisions contribute to the elongation of the developing neural tube in embryos.

Folate and Synthetic Folic Acid Content in Canadian Fortified Foods Two Decades After Mandatory Fortification.

In 1998, Health Canada mandated folic acid fortification of white flour and enriched grain products to prevent neural tube defects. At the time, neither the Canadian Nutrient File (CNF) nor product labels reflected the actual folate content of foods. We aimed to assess if 20 years post-fortification, the CNF values for total folate and synthetic folic acid accurately reflect amounts determined by direct analysis. Using the 2001 Food Expenditure Survey and ACNielsen Company data, we identified 10 to 15 of the most purchased fortified foods across 7 food categories in Canada. Total folate concentrations were determined by tri-enzyme digestion and microbial assay. Folic acid concentrations were determined using liquid chromatography tandem mass spectrometry. Except for "cooked pastas", mean total folate content of foods (n=89) were significantly higher than CNF values across categories (p<0.05), reflecting 167% ± 54 of CNF values. Similarly, mean folic acid content of foods was higher than CNF values for all categories except "cooked pastas" (p<0.05), with a mean of 188% ± 94 of CNF values; the latter CNF values included uncooked pasta. In sum, 20 years post-fortification, and 10 years since the last direct measurement, CNF and product label values still underestimate actual total folate and the folic acid content of foods. These findings emphasize that dietary estimates established using the CNF may significantly underestimate actual intakes and thus caution should be exercised when interpreting estimates of nutritional adequacy based on these values.

RSG1 is required for cilia-dependent neural tube closure.

Cilia play a key role in the regulation of signaling pathways required for embryonic development, including the proper formation of the neural tube, the precursor to the brain and spinal cord. Forward genetic screens were used to generate mouse lines that display neural tube defects (NTD) and secondary phenotypes useful in interrogating function. We describe here the L3P mutant line that displays phenotypes of disrupted Sonic hedgehog signaling and affects the initiation of cilia formation. A point mutation was mapped in the L3P line to the gene Rsg1, which encodes a GTPase-like protein. The mutation lies within the GTP-binding pocket and disrupts the highly conserved G1 domain. The mutant protein and other centrosomal and IFT proteins still localize appropriately to the basal body of cilia, suggesting that RSG1 GTPase activity is not required for basal body maturation but is needed for a downstream step in axonemal elongation.

Fertility and Pregnancy after Bariatric Surgery: Challenges and Solutions

Abstract Introduction Obesity is increasing worldwide, and bariatric surgery (BS) is increasingly employed for weight management in women of reproductive age. An interplay between pregnancy and BS is very likely. A review of the challenges faced and solutions needed is warranted. Materials and Methods A narrative, nonsystematic review of the international literature from a single online database (PubMed) was performed on July 23, 2023. All articles were included. The retrieved relevant literature is narrated in a concise thematic account. Results BS carries major metabolic, mechanical, and vascular benefits, possibly accompanied by nutritional, vitamins, minerals, and micronutrient deficiencies, which might be clinical or subclinical. A few of the frequently reported postbariatric nutritional jeopardies could be augmented by the physiological changes of pregnancy, which need a different approach to management. Nutritional deficiencies during pregnancy could carry both maternal and fetal short- and long-term risks. Fetal risks may range from miscarriage to low birth weight, neural tube defects, congenital anomalies, cognitive impairment, and internal organ dysplasia. Postbariatric status is, by default, a high-risk pregnancy category, given the altered biochemical, vasomotor, and mechanical indices of any lady treated with BS. Postgastric bypass hypoglycemia (PGBH) is a relatively common phenomenon during pregnancy, and it usually calls for multidisciplinary action to control. A dedicated monitoring protocol before, during, and after pregnancy has been suggested in several guidelines to guard against the potentially devastating consequences to both mother and fetus. Conclusions Weight reduction after BS enhances fertility. The optimum timing for ladies treated with BS to get pregnant is not very well established yet. However, various societies have provided multidisciplinary management guidance of management prior to and during pregnancy. Many nutritional supplements that are not routinely prescribed during pregnancy will be essential for those treated with BS. Further studies are still warranted to ensure the safe interim between BS and conception as well as the safety of various doses of medications used for postbariatric individuals, for instance, medications used for PGBH.

Full Recovery of Hearing After Resection of a Large Epidermoid Tumor at the Cerebellopontine Angle: 2-Dimensional Operative Video.

Epidermoid tumors are benign, slow-growing lesions, originating from misplaced ectodermal cells that become trapped during neural tube closure.1 The cerebellopontine angle (CPA) is the most common intracranial location for epidermoid tumors, accounting for approximately 60% of cases.2 Treatment of epidermoid tumors consists of surgical resection, with the goal of gross total resection.3 Here, we describe the case of a patient with a large epidermoid tumor at the CPA causing near-complete hearing loss, who remarkably experienced full recovery of hearing after resection of the tumor. The patient is a 37-year-old woman who presented to our clinic with a CPA tumor causing severe hearing loss consisting of class D hearing and a word recognition score of 5% on audiological examination. Radiographically, the tumor demonstrated significant mass effect on the right cranial nerves VII and VIII with prominent extension into the internal auditory canal. Given the patient's profound hearing loss, she consented to receive a right retrosigmoid craniotomy for resection of the lesion. Although cranial nerves VII and VIII were heavily invested in the tumor, we were able to systematically resect the lesion from the CPA and internal auditory canal, and achieve a gross total resection. Histological examination confirmed the diagnosis of an epidermoid tumor. Remarkably, the patient's audiogram at 3-month follow-up demonstrated complete recovery of hearing in her right ear with a word recognition score of 100% and normal hearing sensitivity across all tested frequencies.