Spina Bifida: A Review of the Genetics, Pathophysiology and Emerging Cellular Therapies

Recommendations for long-term follow-up care of secondary health conditions in spinal cord injury/disorder: a systematic review

Objectives

The purpose of this systematic review is to provide an overview of published follow-up care programs of primary and secondary health conditions (SHCs) in spinal cord injury/disorder (SCI/D) and spina bifida and describe recommendations on content, frequency, setting of follow-up care programs for persons with SCI/D and spina bifida.

Methods

According to the sequence of procedures of the AWMF (Association of the Scientific Medical Societies in Germany) a systematic literature search was performed (in PubMed, Cochrane Library and nine additional databases for guidelines) between 5 September 2019 and 22 September 2019. Publications (Jan. 2008-Dec. 2018) and guidelines (up to 2018) published in English or German and describing an evidence-based follow-up care program for persons with SCI/D or spina bifida were included.

Results

The systematic literature search found 1973 publications in PubMed and Cochrane Library, resulting in 19 papers for SCI/D and 6 for Spina bifida. Additionally, we included 34 guidelines developed by reputable committees or medical associations. All eligible guidelines, and publications, were rated and classified according to the guidance of AWMF. Of the retrieved publications, and guidelines, level of evidence of follow-up care programs was mostly based on informal procedures and expert opinion or formally consent based expert opinion. None of the guidelines, or publications described an evidence based comprehensive clinical practice guideline (CPG) for follow-up care for people with SCI/D or spina bifida.

Conclusion

Based on the comprehensive and extensive literature research conducted, regular (annual) follow-up care appointments at specialized SCI clinics are recommended. There is a notable absence of a comprehensive CPG covering all relevant health conditions for long-term follow-up in SCI/D or spina bifida. In order to provide persons with SCI/D with up-to-date and best possible medical and rehabilitative care, a CPG for follow-up care is urgently needed. In response to this gap, the German-speaking Medical Society of Paraplegia (DMGP) has commissioned its members to establish a guideline for follow-up care for individuals with SCI/D. The current review serves as an evidence-based framework for the development of this guideline.

Genetic Markers of Spina Bifida in an Indian Cohort

Objective

To identify the genetic markers of spina bifida through a systematic survey of the exome in an Indian cohort.

Materials and Methods

Three consecutive patients (P1: 1 year, male; P2: 2.8 years, male; and P3: 10 years, female) with spina bifida (lumbosacral meningomyelocele) underwent whole-exome sequencing (libraries: SureSelect Human All Exon V8; sequencing: 2 * 150 bp paired-end run, 100×) with NovaSeq 6000. Data analysis was performed using SMART-One™ (secondary analysis) and SMARTer™ (tertiary analysis) for automated quality check, alignment (GRCh38/hg38), variant calling, annotation (ClinVar, OMIM, avsnp150, 1000 Genomes v5b, ExAC v0.3, gnomAD v4.0, and esp6500vi2all v0.0.25), v0.0.25), interpretation. The pathogenic and likely pathogenic (ClinVar/ InterVar), non-synonymous, exonic markers (read depth ≥ 5) were matched with the Familial Neural Tube Defects (Version 1.10) panel (FNTD panel).

Results

Pathogenic variants overlapping with the FNTD panel were MTRR, CC2D2A, and ZIC2 in P1 and P2, TGIF1 in P1 only, and none in P3. Novel pathogenic/likely pathogenic variants common to all three patients were PRUNE1, PKD1, PDZD2, and DAB2 in the homozygous state as well as in the heterozygous state, PLK1 and NLGN2. The possible role of such markers in etiopathogenesis was explored through a literatur search.

Conclusions

The genetic landscape of the spina bifida in an Indian cohort is diverse compared to that reported from other parts of the world. A comprehensive catalog of single-nucleotide variants in the etiopathogenesis of the spina bifida on a background of the Familial Neural Tube Defects Panel has been generated.

Zinc oxide nanoparticles induces cell death and consequently leading to incomplete neural tube closure through oxidative stress during embryogenesis

The implementation of Zinc oxide nanoparticles (ZnO NPs) raises concerns regarding their potential toxic effects on human health. Although more and more researches have confirmed the toxic effects of ZnO NPs, limited attention has been given to their impact on the early embryonic nervous system. This study aimed to explore the impact of exposure to ZnO NPs on early neurogenesis and explore its underlying mechanisms. We conducted experiments here to confirm the hypothesis that exposure to ZnO NPs causes neural tube defects in early embryonic development. We first used mouse and chicken embryos to confirm that ZnO NPs and the Zn2+ they release are able to penetrate the placental barrier, influence fetal growth and result in incomplete neural tube closure. Using SH-SY5Y cells, we determined that ZnO NPs-induced incomplete neural tube closure was caused by activation of various cell death modes, including ferroptosis, apoptosis and autophagy. Moreover, dissolved Zn2+ played a role in triggering widespread cell death. ZnO NPs were accumulated within mitochondria after entering cells, damaging mitochondrial function and resulting in the over production of reactive oxygen species, ultimately inducing cellular oxidative stress. The N-acetylcysteine (NAC) exhibits significant efficacy in mitigating cellular oxidative stress, thereby alleviating the cytotoxicity and neurotoxicity brought about by ZnO NPs. These findings indicated that the exposure of ZnO NPs in early embryonic development can induce cell death through oxidative stress, resulting in a reduced number of cells involved in early neural tube closure and ultimately resulting in incomplete neural tube closure during embryo development. The findings of this study could raise public awareness regarding the potential risks associated with the exposure and use of ZnO NPs in early pregnancy.

The hope, hype and obstacles surrounding cell therapy

Cell therapy offers hope, but it also presents challenges, most particularly the limited ability of human organs and tissues to regenerate. Since many diseases are associated with irreversible pathophysiological or traumatic changes, stem cells and their derivatives are unable to secure healing. Although regenerative medicine offers chances for improvements in many diseases, such as type one diabetes and Parkinson's disease, it cannot eliminate the primary cause of many of them. While successes can be expected for diseases such as sickle cell disease, this is not the case for hereditary diseases with varied mutation types or for ciliopathies, which start in embryogenesis. In this complicated medical environment, synthetic biology offers some solutions, but their implementation will take many years. Still, positive examples such as CAR-T therapy offer hope.

Nursing management of patients dealing with spina bifida: from the prenatal diagnosis to adulthood / nursing intervention for the improvement of the impact of urinary and fecal incontinence on the quality of life of people dealing with spina bifida

BACKGROUND

Urinary and fecal incontinence in people dealing with spina bifida, has inevitably an influence on the quality of life. In this analysis, the degree of education on how to manage incontinence and retention is studied, as well as the problems those might create and the consequential degree of autonomy and independence reached into the management of those. The main goal is to increase both nursing assistance and the education of the people dealing with spina bifida.

METHODS

A multiple-choice questionnaire with open questions, concerning the bowel and bladder management was structured by all the authors and shared by the Google Docs platform among the members of the ASBI (Associazione Spina Bifida Italia) by the secretariat of the association itself. 125 patients affected by Spina Bifida voluntarily decided to participate and complete the questionnaire. The questionnaire didn't set any limits as regards the age. For minors, its completion was made under the observation of the caregivers who gave their consent. All the authors participated to administration of the questionnaire to minors.

RESULTS

out of 125 participants, 80 were females and 25 males. The questions concerned the level of deambulation (the 35,2% was autonomous, the 30,4% were people who use wheelchairs while the 34,4% is aid-supported), urinary incontinence, with great concern to the self-catheterization technique (the 80,8% claimed to be autonomous in performing self-catheterization, unlike the remaining 19,2%) and the impact of the said incontinence on social life (the 59,2% claimed they do not feel restrained because of their bladder incontinence or retention, unlike the remaining 40,8%). Lastly, we focused on fecal constipation and incontinence (the 57,6% claimed to struggle with incontinence, the 12% claimed they don't and the 30,4% struggles with both conditions), on the ability of the people dealing with this to intervene to prevent unpleasant situations, in particular by using trans-anal irrigation (the 57,6% doesn't feel autonomous in performing it).

CONCLUSION

urinary and fecal incontinence have, of course, an impact on the quality of life of people dealing with spina bifida. Nevertheless, we can observe that it is possible to improve the quality of life of these people, letting them feel confident enough to take part in social activities, through education from an incredibly young age, from 0 up to 25 years old and over, supplied by the medical staff and mostly by the parents (previously educated by the medical staff as well).

Profile of a Multivariate Observation under Destructive Sampling-A Monte Carlo Approach to a Case of Spina Bifida

A biodegradable hybrid polymer patch was invented at the University of Cincinnati to cover gaps on the skin over the spinal column of a growing fetus, characterized by the medical condition spina bifida. The inserted patch faces amniotic fluid (AF) on one side and cerebrospinal fluid on the other side. The goal is to provide a profile of the roughness of a patch over time at 0, 4, 8, 12, and 16 weeks with a 95% confidence band. The patch is soaked in a test tube filled with either amniotic fluid (AF) or phosphate-buffered saline (PBS) in the lab. If roughness is measured at any time point for a patch, the patch is destroyed. Thus, it is impossible to measure roughness at all weeks of interest for any patch. It is important to assess the roughness of a patch because the rougher the patch is, the faster the skin grows under the patch. We use a model-based approach with Monte Carlo simulations to estimate the profile over time with a 95% confidence band. The roughness profiles are similar with both liquids. The profile can be used as a template for future experiments on the composition of patches.

Double Myelomeningocele Repair by Fetal Surgery with a Single Micro-Hysterotomy

INTRODUCTION

Open spina bifida (OSB) is the most common congenital anomaly of the central nervous system. It is associated with severe neurodevelopmental delay, motor impairment, hydrocephalus, and bowel and bladder dysfunction. In selected cases, intrauterine spina bifida repair has been shown to improve neonatal outcomes. Rarely, the spine can have a double defect compromising two different segments and there is a lack of evidence on the feasibility and benefits of intrauterine repair in these cases.

CASE PRESENTATION

We present a case with both cervicothoracic and lumbosacral myelomeningocele, Arnold-Chiari malformation type II and bilateral ventriculomegaly, that was treated successfully at 25 weeks with open micro-neurosurgery. Double myelomeningocele was successfully treated through a single 2-cm micro-hysterotomy, by performing external versions to sequentially expose and repair both defects. Weekly postoperative follow-up showed no progression of ventriculomegaly or complications attributable to the procedure. Preterm rupture of membranes prompted a conventional cesarean delivery at 32 weeks of gestation. Neurodevelopmental outcome at 20 months was within normal ranges, having achieved ambulation without orthopedic support and with no need for ventriculoperitoneal shunting.

CONCLUSION

This report demonstrates for the first time the feasibility of double OSB repair through a single 2-cm micro-hysterotomy, suggesting that selected isolated cases of double myelomeningocele could be candidates for fetal intervention. Further prospective studies should be carried out to assess the potential benefit of double OSB intrauterine open repair.

Molecular landscape of congenital vertebral malformations: recent discoveries and future directions

Vertebral malformations (VMs) pose a significant global health problem, causing chronic pain and disability. Vertebral defects occur as isolated conditions or within the spectrum of various congenital disorders, such as Klippel-Feil syndrome, congenital scoliosis, spondylocostal dysostosis, sacral agenesis, and neural tube defects. Although both genetic abnormalities and environmental factors can contribute to abnormal vertebral development, our knowledge on molecular mechanisms of numerous VMs is still limited. Furthermore, there is a lack of resource that consolidates the current knowledge in this field. In this pioneering review, we provide a comprehensive analysis of the latest research on the molecular basis of VMs and the association of the VMs-related causative genes with bone developmental signaling pathways. Our study identifies 118 genes linked to VMs, with 98 genes involved in biological pathways crucial for the formation of the vertebral column. Overall, the review summarizes the current knowledge on VM genetics, and provides new insights into potential involvement of biological pathways in VM pathogenesis. We also present an overview of available data regarding the role of epigenetic and environmental factors in VMs. We identify areas where knowledge is lacking, such as precise molecular mechanisms in which specific genes contribute to the development of VMs. Finally, we propose future research avenues that could address knowledge gaps.

The science of uncertainty guides fetal-neonatal neurology principles and practice: diagnostic-prognostic opportunities and challenges

Fetal-neonatal neurologists (FNNs) consider diagnostic, therapeutic, and prognostic decisions strengthened by interdisciplinary collaborations. Bio-social perspectives of the woman's health influence evaluations of maternal-placental-fetal (MPF) triad, neonate, and child. A dual cognitive process integrates "fast thinking-slow thinking" to reach shared decisions that minimize bias and maintain trust. Assessing the science of uncertainty with uncertainties in science improves diagnostic choices across the developmental-aging continuum. Three case vignettes highlight challenges that illustrate this approach. The first maternal-fetal dyad involved a woman who had been recommended to terminate her pregnancy based on an incorrect diagnosis of an encephalocele. A meningocele was subsequently identified when she sought a second opinion with normal outcome for her child. The second vignette involved two pregnancies during which fetal cardiac rhabdomyoma was identified, suggesting tuberous sclerosis complex (TSC). One woman sought an out-of-state termination without confirmation using fetal brain MRI or postmortem examination. The second woman requested pregnancy care with postnatal evaluations. Her adult child experiences challenges associated with TSC sequelae. The third vignette involved a prenatal diagnosis of an open neural tube defect with arthrogryposis multiplex congenita. The family requested prenatal surgical closure of the defect at another institution at their personal expense despite receiving a grave prognosis. The subsequent Management of Myelomeningocele Study (MOMS) would not have recommended this procedure. Their adult child requires medical care for global developmental delay, intractable epilepsy, and autism. These three evaluations involved uncertainties requiring shared clinical decisions among all stakeholders. Falsely negative or misleading positive interpretation of results reduced chances for optimal outcomes. FNN diagnostic skills require an understanding of dynamic gene-environment interactions affecting reproductive followed by pregnancy exposomes that influence the MPF triad health with fetal neuroplasticity consequences. Toxic stressor interplay can impair the neural exposome, expressed as anomalous and/or destructive fetal brain lesions. Functional improvements or permanent sequelae may be expressed across the lifespan. Equitable and compassionate healthcare for women and families require shared decisions that preserve pregnancy health, guided by person-specific racial-ethnic, religious, and bio-social perspectives. Applying developmental origins theory to neurologic principles and practice supports a brain health capital strategy for all persons across each generation.

Sample Preparation Method for MALDI Mass Spectrometry Imaging of Fresh-Frozen Spines

Technologies assessing the lipidomics, genomics, epigenomics, transcriptomics, and proteomics of tissue samples at single-cell resolution have deepened our understanding of physiology and pathophysiology at an unprecedented level of detail. However, the study of single-cell spatial metabolomics in undecalcified bones faces several significant challenges, such as the fragility of bone, which often requires decalcification or fixation leading to the degradation or removal of lipids and other molecules. As such, we describe a method for performing mass spectrometry imaging on undecalcified spine that is compatible with other spatial omics measurements. In brief, we use fresh-frozen rat spines and a system of carboxyl methylcellulose embedding, cryofilm, and polytetrafluoroethylene rollers to maintain tissue integrity while avoiding signal loss from variations in laser focus and artifacts from traditional tissue processing. This reveals various tissue types and lipidomic profiles of spinal regions at 10 μm spatial resolutions using matrix-assisted laser desorption/ionization mass spectrometry imaging. We expect this method to be adapted and applied to the analysis of the spinal cord, shedding light on the mechanistic aspects of cellular heterogeneity, development, and disease pathogenesis underlying different bone-related conditions and diseases. This study furthers the methodology for high spatial metabolomics of spines and adds to the collective efforts to achieve a holistic understanding of diseases via single-cell spatial multiomics.

The influence of different sugammadex doses on neural tube development in early-stage chick embryos

BACKGROUND

Sugammadex is a modified gamma-cyclodextrin that has been developed with the goal of reversing the steroidal neuromuscular blocking agents. The aim of the present study is to investigate the effects of different sugammadex doses on embryologic and neural tube development in an early-stage chick embryo model.

METHODS

A total of 100 specific pathogen-free, fertilized domestic chicken eggs were randomly divided into five groups (n = 20, each), and placed in an automatic cycle incubator. The eggs in the "control (C)" group were incubated without administration of any drug till the end of the experiment. Sub-blastodermic administration of 0.9% NaCl as vehicle control (VC) and different doses of sugammadex solutions prepared with the latter [2 mg/mL (LD), 4 mg/mL (MD), 16 mg/mL (HD)] were performed at 30 hr of incubation. All embryos were removed from the eggs at 72 hr when they were expected to reach Hamburger-Hamilton (HH) stages 19-20, then they were fixed, and evaluated histo-morphologically.

RESULTS

Embryonic development was not observed in 11 eggs (1 in C, 1 in VC; 3 in LD, 3 in MD, and 3 in HD). All the developed embryos were compatible with the HH stages 19-20. A neural tube closure defect was detected in one embryo in the HD group. No statistically significant difference was found between the groups in terms of embryonic and neural tube developments.

CONCLUSIONS

No significant association was found between the drug and adverse outcomes; however, a trend with dosing was seen. Further studies are required before conclude on safety and extrapolate these results to human beings.

Spatial lipidomics of fresh-frozen spines

Technologies assessing the lipidomics, genomics, epigenomics, transcriptomics, and proteomics of tissue samples at single-cell resolution have deepened our understanding of physiology and pathophysiology at an unprecedented level of detail. However, the study of single-cell spatial metabolomics in undecalcified bones faces several significant challenges, such as the fragility of bone which often requires decalcification or fixation leading to the degradation or removal of lipids and other molecules and. As such, we describe a method for performing mass spectrometry imaging on undecalcified spine that is compatible with other spatial omics measurements. In brief, we use fresh-freeze rat spines and a system of carboxyl methylcellulose embedding, cryofilm, and polytetrafluoroethylene rollers to maintain tissue integrity, while avoiding signal loss from variations in laser focus and artifacts from traditional tissue processing. This reveals various tissue types and lipidomic profiles of spinal regions at 10 μm spatial resolutions using matrix-assisted laser desorption/ionization mass spectrometry imaging. We expect this method to be adapted and applied to the analysis of spinal cord, shedding light on the mechanistic aspects of cellular heterogeneity, development, and disease pathogenesis underlying different bone-related conditions and diseases. This study furthers the methodology for high spatial metabolomics of spines, as well as adds to the collective efforts to achieve a holistic understanding of diseases via single-cell spatial multi-omics.

Multidisciplinary Management of Children with Occult Spinal Dysraphism: A Comprehensive Journey from Birth to Adulthood

Occult spinal dysraphism (OSD) comprises different forms of failure in embryogenic development that can lead to genitourinary, spinal, or lower limb alterations, thus determining progressive neurological deterioration. The correct management of children harboring OSD represents a significant issue during their life up to adulthood. However, patients often have to entertain individual consultations with each specialist. We settled on a multidisciplinary team comprising pediatric neurosurgeons, urologists, neurologists, orthopedists, and other supporting physicians. We present the results of such actions by analyzing a series of 141 children with OSD subjected to neurosurgical procedures, evaluating the impact of multidisciplinary management on outcomes. We also evaluated the specific actions according to the different ages of OSD patients from birth to adulthood to provide a schematic plan that could represent a basis for establishing and disseminating the need for a multidisciplinary approach in OSD management. The multidisciplinary team allows all consultants to see the patient together, covering specific aspects of history and examination pertinent to their management. Offering a one-stop service prevents coordination issues between the different medical teams, avoids delays or cancellations of the various appointments, optimizes cost-effectiveness, and improves efficiency and parents’ satisfaction.