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1.
Mol Cell ; 70(5): 936-948.e7, 2018 06 07.
Article in English | MEDLINE | ID: mdl-29883610

ABSTRACT

Necroptosis is an important form of lytic cell death triggered by injury and infection, but whether mixed lineage kinase domain-like (MLKL) is sufficient to execute this pathway is unknown. In a genetic selection for human cell mutants defective for MLKL-dependent necroptosis, we identified mutations in IPMK and ITPK1, which encode inositol phosphate (IP) kinases that regulate the IP code of soluble molecules. We show that IP kinases are essential for necroptosis triggered by death receptor activation, herpesvirus infection, or a pro-necrotic MLKL mutant. In IP kinase mutant cells, MLKL failed to oligomerize and localize to membranes despite proper receptor-interacting protein kinase-3 (RIPK3)-dependent phosphorylation. We demonstrate that necroptosis requires IP-specific kinase activity and that a highly phosphorylated product, but not a lowly phosphorylated precursor, potently displaces the MLKL auto-inhibitory brace region. These observations reveal control of MLKL-mediated necroptosis by a metabolite and identify a key molecular mechanism underlying regulated cell death.


Subject(s)
Colonic Neoplasms/enzymology , Inositol Phosphates/metabolism , Protein Kinases/metabolism , Binding Sites , Cell Death/drug effects , Colonic Neoplasms/genetics , Colonic Neoplasms/pathology , Colonic Neoplasms/virology , Gene Expression Regulation, Enzymologic , Gene Expression Regulation, Neoplastic , HT29 Cells , Herpesvirus 1, Human/pathogenicity , Humans , Jurkat Cells , Mutation , Phosphorylation , Phosphotransferases (Alcohol Group Acceptor)/genetics , Phosphotransferases (Alcohol Group Acceptor)/metabolism , Protein Kinases/genetics , Receptor-Interacting Protein Serine-Threonine Kinases/genetics , Receptor-Interacting Protein Serine-Threonine Kinases/metabolism , Signal Transduction/drug effects , Tumor Necrosis Factor-alpha/pharmacology
2.
Circulation ; 147(10): 824-840, 2023 03 07.
Article in English | MEDLINE | ID: mdl-36524479

ABSTRACT

BACKGROUND: Brugada syndrome (BrS) is an inherited arrhythmia syndrome caused by loss-of-function variants in the cardiac sodium channel gene SCN5A (sodium voltage-gated channel alpha subunit 5) in ≈20% of subjects. We identified a family with 4 individuals diagnosed with BrS harboring the rare G145R missense variant in the cardiac transcription factor TBX5 (T-box transcription factor 5) and no SCN5A variant. METHODS: We generated induced pluripotent stem cells (iPSCs) from 2 members of a family carrying TBX5-G145R and diagnosed with Brugada syndrome. After differentiation to iPSC-derived cardiomyocytes (iPSC-CMs), electrophysiologic characteristics were assessed by voltage- and current-clamp experiments (n=9 to 21 cells per group) and transcriptional differences by RNA sequencing (n=3 samples per group), and compared with iPSC-CMs in which G145R was corrected by CRISPR/Cas9 approaches. The role of platelet-derived growth factor (PDGF)/phosphoinositide 3-kinase (PI3K) pathway was elucidated by small molecule perturbation. The rate-corrected QT (QTc) interval association with serum PDGF was tested in the Framingham Heart Study cohort (n=1893 individuals). RESULTS: TBX5-G145R reduced transcriptional activity and caused multiple electrophysiologic abnormalities, including decreased peak and enhanced "late" cardiac sodium current (INa), which were entirely corrected by editing G145R to wild-type. Transcriptional profiling and functional assays in genome-unedited and -edited iPSC-CMs showed direct SCN5A down-regulation caused decreased peak INa, and that reduced PDGF receptor (PDGFRA [platelet-derived growth factor receptor α]) expression and blunted signal transduction to PI3K was implicated in enhanced late INa. Tbx5 regulation of the PDGF axis increased arrhythmia risk due to disruption of PDGF signaling and was conserved in murine model systems. PDGF receptor blockade markedly prolonged normal iPSC-CM action potentials and plasma levels of PDGF in the Framingham Heart Study were inversely correlated with the QTc interval (P<0.001). CONCLUSIONS: These results not only establish decreased SCN5A transcription by the TBX5 variant as a cause of BrS, but also reveal a new general transcriptional mechanism of arrhythmogenesis of enhanced late sodium current caused by reduced PDGF receptor-mediated PI3K signaling.


Subject(s)
Brugada Syndrome , Humans , Mice , Animals , Phosphatidylinositol 3-Kinases/metabolism , Phenotype , Arrhythmias, Cardiac/genetics , Arrhythmias, Cardiac/metabolism , Myocytes, Cardiac/metabolism , Receptors, Platelet-Derived Growth Factor/genetics , Receptors, Platelet-Derived Growth Factor/metabolism , Sodium/metabolism , NAV1.5 Voltage-Gated Sodium Channel/genetics , NAV1.5 Voltage-Gated Sodium Channel/metabolism
3.
Am J Hum Genet ; 108(1): 100-114, 2021 01 07.
Article in English | MEDLINE | ID: mdl-33352116

ABSTRACT

Chiari I malformation (CM1), the displacement of the cerebellum through the foramen magnum into the spinal canal, is one of the most common pediatric neurological conditions. Individuals with CM1 can present with neurological symptoms, including severe headaches and sensory or motor deficits, often as a consequence of brainstem compression or syringomyelia (SM). We conducted whole-exome sequencing (WES) on 668 CM1 probands and 232 family members and performed gene-burden and de novo enrichment analyses. A significant enrichment of rare and de novo non-synonymous variants in chromodomain (CHD) genes was observed among individuals with CM1 (combined p = 2.4 × 10-10), including 3 de novo loss-of-function variants in CHD8 (LOF enrichment p = 1.9 × 10-10) and a significant burden of rare transmitted variants in CHD3 (p = 1.8 × 10-6). Overall, individuals with CM1 were found to have significantly increased head circumference (p = 2.6 × 10-9), with many harboring CHD rare variants having macrocephaly. Finally, haploinsufficiency for chd8 in zebrafish led to macrocephaly and posterior hindbrain displacement reminiscent of CM1. These results implicate chromodomain genes and excessive brain growth in CM1 pathogenesis.


Subject(s)
Arnold-Chiari Malformation/genetics , DNA-Binding Proteins/genetics , Polymorphism, Single Nucleotide/genetics , Adult , Animals , Arnold-Chiari Malformation/pathology , Brain/pathology , Case-Control Studies , Female , Haploinsufficiency/genetics , Humans , Magnetic Resonance Imaging/methods , Male , Syringomyelia/genetics , Exome Sequencing/methods , Zebrafish/genetics
4.
Childs Nerv Syst ; 40(1): 197-204, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37864710

ABSTRACT

BACKGROUND: Dural arteriovenous fistulas (dAVF) are arteriovenous shunts in communication with the dural vasculature in the brain or spine. Apart from single-center series, risk factors and treatment outcomes for pediatric dAVFs are largely undescribed. METHODS: We performed a systematic literature review of pediatric (< 18 years at diagnosis) intracranial and spinal dAVF according to PRISMA guidelines. We queried PubMed, CINAHL, SCOPUS, and Embase databases without time/date restriction. Search strings included a variety of MeSH keywords relating to dural AV fistulas in combination with MeSH keywords related to pediatric cases (see Appendix). Manuscripts describing patients diagnosed with dural sinus malformations or pial AVF were excluded. RESULTS: We identified 61 studies describing 69 individual patients. Overall, dAVF were more common in males (55.1%) with a mean age of diagnosis (5.17 ± 4.42 years). Approximately 20.2% of patients presented with cardiovascular disease (CVD), and 31.9% were discovered incidentally on neuroimaging studies. Transverse-sigmoid junction was the most common location (17.3%). Ninety-three percent (64 patients) were treated, most commonly using endovascular embolization (68.1%) followed by surgery (8.7%) and radiosurgery (2.9%). Almost half (43.8%) of dAVFs were completely obliterated. Of the 64 procedures, there were 19 neurological complications (29.7%) of varying severity where 12.5% were considered transient (i.e., pseudomeningocele) and 17.2% permanent (i.e., mortality secondary to acute sinus thrombosis, etc.). CONCLUSION: There is a paucity of information on pediatric dAVFs. This systematic review summarizes the published cases of dAVFs in the pediatric population. While the rate of missing data is high, there is publication bias, and precise details regarding complications are difficult to ascertain, this review serves as a descriptive summary of pediatric dAVFs.


Subject(s)
Arteriovenous Fistula , Central Nervous System Vascular Malformations , Embolization, Therapeutic , Radiosurgery , Male , Humans , Child , Infant , Child, Preschool , Treatment Outcome , Embolization, Therapeutic/methods , Central Nervous System Vascular Malformations/diagnostic imaging , Central Nervous System Vascular Malformations/therapy , Arteriovenous Fistula/diagnostic imaging , Arteriovenous Fistula/therapy , Arteriovenous Fistula/etiology
5.
Childs Nerv Syst ; 2024 Jul 20.
Article in English | MEDLINE | ID: mdl-39030337

ABSTRACT

INTRODUCTION: Myelomeningocele (MMC) is the most common neural tube defect, but rarely seen in premature infants. Most centers advocate for closure of MMC within 24 h of birth. However, this is not always possible in severely premature infants. Given the rarity of this patient population, we aimed to share our institutional experience and outcomes of severely premature infants with MMC. METHODS: We performed a retrospective, observational review of premature infants (≤ 32 weeks gestational age) identified through our multidisciplinary spina bifida clinic (1995-2021) and surgical logs. Descriptive statistics were compiled about this sample including timing of MMC closure and incidence of adverse events such as sepsis, CSF diversion, meningitis, and death. RESULTS: Eight patients were identified (50% male) with MMC who were born ≤ 32 weeks gestational age. Mean gestational age of the population was 27.3 weeks (SD 3.5). Median time to MMC closure was 1.5 days (IQR = 1-80.8). Five patients were taken for surgery within the recommended 48 h of birth; 2 patients underwent significantly delayed closure (107 and 139 days); and one patient's defect epithelized without surgical intervention. Six of eight patients required permanent cerebrospinal fluid (CSF) diversion (2 patients were treated with ventriculoperitoneal shunting (VPS), three were treated with endoscopic third ventriculostomy (ETV) with choroid plexus cauterization (CPC) and 1 patient treated with ETV; mean of 3 years after birth, ranging from 1 day to 16 years). Two patients required more than one permanent CSF diversion procedure. Two patients developed sepsis (defined as meeting at least 2/4 SIRS criteria). In both cases of sepsis, patients developed signs and symptoms more than 72 h after birth. Notably, both instances of sepsis occurred unrelated to operative intervention as they occurred before permanent MMC closure. Two patients had intraventricular hemorrhage (both grade III). No patients developed meningitis (defined as positive CSF cultures) prior to MMC closure. Median follow up duration was 9.7 years. During this time epoch, 3 patients died: Two before 2 years of age of causes unrelated to surgical intervention. One of the two patients with grade III IVH died within 24 h of MMC closure. CONCLUSIONS: In our institutional experience with premature infants with MMC, some patients underwent delayed MMC closure. The overall rate of meningitis, sepsis, and mortality for preterm children with MMC was similar to MMC patients born at term.

6.
Childs Nerv Syst ; 40(6): 1721-1729, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38506930

ABSTRACT

INTRODUCTION: Pediatric non-galenic pial arteriovenous fistulas (pAVFs) are rare vascular malformations that are characterized by a pial arterial-venous connection without an intervening capillary bed. Outcomes and treatment strategies for pAVFs are highly individualized, owing to the rarity of the disease and lack of large-scale data guiding optimal treatment approaches. METHODS: We performed a systematic review of pediatric patients (< 18 years at diagnosis) diagnosed with a pAVF by digital subtraction angiogram (DSA). The demographics, treatment modalities, and outcomes were documented for each patient and clinical outcome data was collected. Descriptive information stratified by outcome scores were classified as follows: 1 = excellent (no deficit and full premorbid activity), 2 = good (mild deficit and full premorbid activity), 3 = fair (moderate deficit and impaired activity), 4 = poor (severe deficit and dependent on others), 5 = death. RESULTS: A total of 87 studies involving 231 patients were identified. Median age at diagnosis was 3 years (neonates to 18 years). There was slight male preponderance (55.4%), and 150 subjects (81.1%*) experienced excellent outcomes after treatment. Of the 189 patients treated using endovascular approaches, 80.3% experienced excellent outcomes and of the 15 patients surgically treated subjects 75% had an excellent outcome. The highest rate of excellent outcomes was achieved in patients treated with Onyx (95.2%) and other forms of EvOH (100%). High output heart failure and comorbid vascular lesions tended to result in worse outcomes, with only 54.2% and 68% of subjects experiencing an excellent outcome, respectively. *Outcomes were reported in only 185 patients. CONCLUSION: pAVFs are rare lesions, necessitating aggregation of patient data to inform natural history and optimal treatment strategies. This review summarizes the current literature on pAVF in children, where children presenting with heart failure as a result of high flow through the lesion were less likely to experience an excellent outcome. Prospective, large-scale studies would further characterize pediatric pAVFs and enable quantitative analysis of outcomes to inform best treatment practices.


Subject(s)
Arteriovenous Fistula , Pia Mater , Humans , Child , Arteriovenous Fistula/surgery , Arteriovenous Fistula/diagnostic imaging , Arteriovenous Fistula/therapy , Pia Mater/blood supply , Child, Preschool , Adolescent , Infant , Female , Infant, Newborn , Treatment Outcome , Male , Intracranial Arteriovenous Malformations/therapy , Intracranial Arteriovenous Malformations/diagnostic imaging , Intracranial Arteriovenous Malformations/surgery
7.
Brain ; 145(11): 3755-3762, 2022 11 21.
Article in English | MEDLINE | ID: mdl-35883201

ABSTRACT

Epilepsy surgery is an established safe and effective treatment for selected candidates with drug-resistant epilepsy. In this opinion piece, we outline the clinical and experimental evidence for selectively considering epilepsy surgery prior to drug resistance. Our rationale for expedited surgery is based on the observations that (i) a high proportion of patients with lesional epilepsies (e.g. focal cortical dysplasia, epilepsy-associated tumours) will progress to drug resistance; (ii) surgical treatment of these lesions, especially in non-eloquent areas of brain, is safe; and (iii) earlier surgery may be associated with better seizure outcomes. Potential benefits beyond seizure reduction or elimination include less exposure to antiseizure medications, which may lead to improved developmental trajectories in children and optimize long-term neurocognitive outcomes and quality of life. Further, there exists emerging experimental evidence that brain network dysfunction exists at the onset of epilepsy, where continuing dysfunctional activity could exacerbate network perturbations. This in turn could lead to expanded seizure foci and contribution to the comorbidities associated with epilepsy. Taken together, we rationalize that epilepsy surgery, in carefully selected cases, may be considered prior to drug resistance. Last, we outline the path forward, including the challenges associated with developing the evidence base and implementing this paradigm into clinical care.


Subject(s)
Brain Diseases , Drug Resistant Epilepsy , Epilepsy , Child , Humans , Quality of Life , Epilepsy/drug therapy , Epilepsy/surgery , Epilepsy/complications , Drug Resistant Epilepsy/drug therapy , Drug Resistant Epilepsy/surgery , Drug Resistant Epilepsy/complications , Seizures/complications , Treatment Outcome , Brain Diseases/complications , Drug Resistance , Retrospective Studies
8.
Adv Tech Stand Neurosurg ; 48: 355-369, 2023.
Article in English | MEDLINE | ID: mdl-37770691

ABSTRACT

Corpus callosotomy (CC) is an effective surgical treatment for medically resistant generalized or multifocal epilepsy (MRE). The premise of CC extrapolates from the observation that the corpus callosum is the predominant commissural pathway that allows spread and synchroneity of epileptogenic activity between the hemispheres. Candidacy for CC is typically reserved for patients seeking palliative epilepsy treatment with the goal of reducing the frequency of drop attacks, although reduction of other seizure semiologies (absence, complex partial seizures, and tonic-clonic) has been observed. A reduction in morbidity affiliated with evolution of surgical techniques to perform CC has improved the safety profile of the procedure without necessarily sacrificing efficacy.


Subject(s)
Epilepsy , Psychosurgery , Humans , Epilepsy/surgery , Seizures/surgery , Treatment Outcome , Corpus Callosum/surgery
9.
Childs Nerv Syst ; 39(3): 617-623, 2023 03.
Article in English | MEDLINE | ID: mdl-36308540

ABSTRACT

PURPOSE: Hyponatremia after craniotomy can be associated with increased morbidity. However, the incidence of and factors associated with post-craniotomy hyponatremia in children are not known. METHODS: We performed a retrospective cohort study of patients aged 0-21 years who underwent craniotomy in 2017-2019 at a single center to determine the incidence of and to identify risk factors for hyponatremia after craniotomy. Indications for craniotomy included tumors (excluding craniopharyngioma), epilepsy, intracranial infection, trauma, craniofacial, suboccipital decompression for the treatment of Chiari malformation, and cerebrovascular disease. Hyponatremia was defined as a serum sodium level ≤ 135 mEq/L any time during the postoperative hospital stay. Statistical significance was defined a priori at p < 0.05. RESULTS: Postoperative hyponatremia occurred in 61 (25%) of 240 children. On univariate analysis, hyponatremia was associated with younger age (8.5 vs 6.3 years, p = 0.01), use of preoperative anti-epileptic drugs (p = 0.02), need for blood transfusion (p = 0.02), government/private insurance (p = 0.04), and pre-existing hydrocephalus, defined as the requirement for permanent cerebrospinal fluid (CSF) diversion (p = 0.04). On multivariate analysis, only hydrocephalus (OR 2.95, 95% CI 1.03-8.40) remained statistically significant. Hyponatremia most occurred on the first postoperative day, with normonatremia achieved in a median of 14 (IQR 9.8-24.3) h. Hyponatremia was significantly associated with longer length of stay (median 8 vs 3 days, p < 0.01). CONCLUSION: Hyponatremia was present in 25% of children after craniotomy. Preoperative hydrocephalus as an independent risk factor for hyponatremia after craniotomy.


Subject(s)
Hydrocephalus , Hyponatremia , Pituitary Neoplasms , Humans , Child , Hyponatremia/epidemiology , Hyponatremia/etiology , Retrospective Studies , Craniotomy/adverse effects , Risk Factors , Hydrocephalus/etiology , Pituitary Neoplasms/complications , Postoperative Complications/epidemiology , Postoperative Complications/etiology
10.
J Biol Chem ; 297(5): 101293, 2021 11.
Article in English | MEDLINE | ID: mdl-34634304

ABSTRACT

Golgi-resident bisphosphate nucleotidase 2 (BPNT2) is a member of a family of magnesium-dependent, lithium-inhibited phosphatases that share a three-dimensional structural motif that directly coordinates metal binding to effect phosphate hydrolysis. BPNT2 catalyzes the breakdown of 3'-phosphoadenosine-5'-phosphate, a by-product of glycosaminoglycan (GAG) sulfation. KO of BPNT2 in mice leads to skeletal abnormalities because of impaired GAG sulfation, especially chondroitin-4-sulfation, which is critical for proper extracellular matrix development. Mutations in BPNT2 have also been found to underlie a chondrodysplastic disorder in humans. The precise mechanism by which the loss of BPNT2 impairs sulfation remains unclear. Here, we used mouse embryonic fibroblasts (MEFs) to test the hypothesis that the catalytic activity of BPNT2 is required for GAG sulfation in vitro. We show that a catalytic-dead Bpnt2 construct (D108A) does not rescue impairments in intracellular or secreted sulfated GAGs, including decreased chondroitin-4-sulfate, present in Bpnt2-KO MEFs. We also demonstrate that missense mutations in Bpnt2 adjacent to the catalytic site, which are known to cause chondrodysplasia in humans, recapitulate defects in overall GAG sulfation and chondroitin-4-sulfation in MEF cultures. We further show that treatment of MEFs with lithium (a common psychotropic medication) inhibits GAG sulfation and that this effect depends on the presence of BPNT2. Taken together, this work demonstrates that the catalytic activity of an enzyme potently inhibited by lithium can modulate GAG sulfation and therefore extracellular matrix composition, revealing new insights into lithium pharmacology.


Subject(s)
Enzyme Inhibitors/pharmacology , Glycosaminoglycans/metabolism , Lithium/pharmacology , Phosphoric Monoester Hydrolases/antagonists & inhibitors , Phosphoric Monoester Hydrolases/metabolism , Animals , Catalysis , Cell Line , Glycosaminoglycans/genetics , Mice , Mice, Knockout , Phosphoric Monoester Hydrolases/genetics
11.
Epilepsia ; 63(11): 2754-2781, 2022 11.
Article in English | MEDLINE | ID: mdl-35847999

ABSTRACT

Several instruments and outcomes measures have been reported in pediatric patients undergoing epilepsy surgery. The objective of this systematic review is to summarize, evaluate, and quantify outcome metrics for the surgical treatment of pediatric epilepsy that address seizure frequency, neuropsychological, and health-related quality of life (HRQL). We performed a systematic review according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to identify publications between 2010 and June 2021 from PubMed, Embase, and the Cochrane Database of Systematic Reviews that report clinical outcomes in pediatric epilepsy surgery. Eighty-one articles were included for review. Overall, rates of postoperative seizure frequency were the most common metric reported (n = 78 studies, 96%). Among the seizure frequency metrics, the Engel Epilepsy Surgery Outcome Scale (n = 48 studies, 59%) was most commonly reported. Neuropsychological outcomes, performed in 32 studies (40%) were assessed using 36 different named metrics. HRQL outcomes were performed in 16 studies (20%) using 13 different metrics. Forty-six studies (57%) reported postoperative changes in antiepileptic drug (AED) regimen, and time-to-event analysis was performed in 15 (19%) studies. Only 13 outcomes metrics (1/5 seizure frequency, 6/13 HRQL, 6/36 neuropsychological) have been validated for use in pediatric patients with epilepsy and only 13 have been assessed through reliability studies (4/5 seizure frequency, 6/13 HRQL, and 3/36 neuropsychological). Of the 81 included studies, 17 (21%) used at least one validated metric. Outcome variable metrics in pediatric epilepsy surgery are highly variable. Although nearly all studies report seizure frequency, there is considerable variation in reporting. HRQL and neuropsychological outcomes are less frequently and much more heterogeneously reported. Reliable and validated outcomes metrics should be used to increase standardization and accuracy of reporting outcomes in pediatric patients undergoing epilepsy surgery.


Subject(s)
Epilepsy , Quality of Life , Humans , Child , Reproducibility of Results , Treatment Outcome , Epilepsy/surgery , Epilepsy/psychology , Seizures , Outcome Assessment, Health Care
12.
Childs Nerv Syst ; 37(5): 1485-1494, 2021 05.
Article in English | MEDLINE | ID: mdl-33515058

ABSTRACT

PURPOSE: While conventional statistical approaches have been used to identify risk factors for cerebrospinal fluid (CSF) shunt failure, these methods may not fully capture the complex contribution of clinical, radiologic, surgical, and shunt-specific variables influencing this outcome. Using prospectively collected data from the Hydrocephalus Clinical Research Network (HCRN) patient registry, we applied machine learning (ML) approaches to create a predictive model of CSF shunt failure. METHODS: Pediatric patients (age < 19 years) undergoing first-time CSF shunt placement at six HCRN centers were included. CSF shunt failure was defined as a composite outcome including requirement for shunt revision, endoscopic third ventriculostomy, or shunt infection within 5 years of initial surgery. Performance of conventional statistical and 4 ML models were compared. RESULTS: Our cohort consisted of 1036 children undergoing CSF shunt placement, of whom 344 (33.2%) experienced shunt failure. Thirty-eight clinical, radiologic, surgical, and shunt-design variables were included in the ML analyses. Of all ML algorithms tested, the artificial neural network (ANN) had the strongest performance with an area under the receiver operator curve (AUC) of 0.71. The ANN had a specificity of 90% and a sensitivity of 68%, meaning that the ANN can effectively rule-in patients most likely to experience CSF shunt failure (i.e., high specificity) and moderately effective as a tool to rule-out patients at high risk of CSF shunt failure (i.e., moderately sensitive). The ANN was independently validated in 155 patients (prospectively collected, retrospectively analyzed). CONCLUSION: These data suggest that the ANN, or future iterations thereof, can provide an evidence-based tool to assist in prognostication and patient-counseling immediately after CSF shunt placement.


Subject(s)
Cerebrospinal Fluid Shunts , Hydrocephalus , Adult , Cerebrospinal Fluid Shunts/adverse effects , Child , Humans , Hydrocephalus/diagnostic imaging , Hydrocephalus/surgery , Infant , Machine Learning , Retrospective Studies , Ventriculostomy , Young Adult
13.
Proc Natl Acad Sci U S A ; 115(12): 3000-3005, 2018 03 20.
Article in English | MEDLINE | ID: mdl-29507250

ABSTRACT

Sulfur assimilation is an evolutionarily conserved pathway that plays an essential role in cellular and metabolic processes, including sulfation, amino acid biosynthesis, and organismal development. We report that loss of a key enzymatic component of the pathway, bisphosphate 3'-nucleotidase (Bpnt1), in mice, both whole animal and intestine-specific, leads to iron-deficiency anemia. Analysis of mutant enterocytes demonstrates that modulation of their substrate 3'-phosphoadenosine 5'-phosphate (PAP) influences levels of key iron homeostasis factors involved in dietary iron reduction, import and transport, that in part mimic those reported for the loss of hypoxic-induced transcription factor, HIF-2α. Our studies define a genetic basis for iron-deficiency anemia, a molecular approach for rescuing loss of nucleotidase function, and an unanticipated link between nucleotide hydrolysis in the sulfur assimilation pathway and iron homeostasis.


Subject(s)
Homeostasis/physiology , Intestines/physiology , Iron/metabolism , Sulfur/metabolism , Animals , Gene Expression Regulation, Enzymologic , Genotype , Mice , Mice, Knockout , Nucleotidases
14.
Neurosurg Rev ; 43(3): 873-880, 2020 Jun.
Article in English | MEDLINE | ID: mdl-30397842

ABSTRACT

While deep brain stimulation (DBS) treatment is relatively rare in children, it may have a role in dystonia to reduce motor symptoms and disability. Pediatric DBS studies are sparse and limited by small sample size, and thus, outcomes are poorly understood. Thus, we performed a systematic review of the literature including studies of DBS for pediatric (age < 21) dystonia. Patient demographics, disease causes and characteristics, motor scores, and disability scores were recorded at baseline and at last post-operative follow-up. We identified 19 studies reporting DBS outcomes in 76 children with dystonia. Age at surgery was 13.8 ± 3.9 (mean ± SD) years, and 58% of individuals were male. Post-operative follow-up duration was 2.8 ± 2.8 years. Sixty-eight percent of patients had primary dystonia (PD), of whom 56% had a pathological mutation in DYT1 (DYT1+). Across all patients, regardless of dystonia type, 43.8 ± 36% improvement was seen in Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) motor (-M) scores after DBS, while 43.7 ± 31% improvement was observed in BFMDRS disability (-D) scores. Patients with PD were more likely to experience ≥ 50% improvement (56%) in BFMDRS-M scores compared to patients with secondary causes of dystonia (21%, p = 0.004). DYT1+ patients were more likely to achieve ≥ 50% improvement (65%) in BFMDRS-D than DTY1- individuals (29%, p = 0.02), although there was no difference in BFMDRS-M ≥ 50% improvement rates between DYT1+ (66%) or DYT1- (43%) children (p = 0.11). While DBS is less common in pediatric patients, individuals with severe dystonia may receive worthwhile benefit with neuromodulation treatment.


Subject(s)
Deep Brain Stimulation/methods , Dystonia/therapy , Adolescent , Child , Child, Preschool , Humans , Neurosurgery , Neurosurgical Procedures , Pediatrics , Treatment Outcome
17.
Pediatr Neurosurg ; 54(2): 75-84, 2019.
Article in English | MEDLINE | ID: mdl-30844793

ABSTRACT

BACKGROUND: Occipitocervical distraction injuries (OCDI) in children occur on a wide spectrum of severity, and decisions about treatment suffer from a lack of rigorous guidelines and significant inter-institutional variability. While clear cases of frank atlanto-occipital dislocation (AOD) are treated with surgical stabilization, the approach for less severe cases of OCDI is not standardized. These patients require a careful assessment of both radiographic and clinical criteria, as part of a complex risk-benefit analysis, to establish whether occipitocervical fusion (OCF) is indicated. Here, we performed a systematic review of the literature that describes traumatic OCDI in children < 18 years of age. SUMMARY: We performed a systematic review, according to PRISMA guidelines, of children < 18 years of age presenting with traumatic etiologies of OCDI. We searched PubMed to identify papers congruent with these criteria. Exclusion criteria included (1) reports on atraumatic causes of OCDI and (2) studies with insufficient clinical and radiographic details on individual patients. We identified 16 reports describing a total of 144 patients treated for pediatric traumatic OCDI. Based on the synthesis of these findings and the collective experience of the authors, we present the demographic, clinical, and radiographic factors that underlie OC instability, which we hope will serve as components of a grading system in the future. We considered various clinical and radiographic findings including: (1) the mechanism of injury, (2) the patient's age, (3) CT/CT angiography of head and neck findings and parameters, (4) MRI findings, and (5) neurological exam, for the purpose of determining the severity of the OCDI and offering treatment guidelines based on the summative risk of underlying OC instability. Key Messages: OCDI is a potentially devastating injury, especially in children. Although missing the diagnosis can have potentially catastrophic consequences, reverting to surgical fixation in less severe cases can subject children to unnecessary operative risk and permanently reduce their range of motion. After reviewing all the available reports of pediatric traumatic OCDI in the neurosurgical literature, we propose an outline of clinical and radiographic factors influencing underlying OC instability that could be incorporated into a grading scale to guide treatment. We hope this study stimulates discussion on the standardization of treatment for pediatric OCDI.


Subject(s)
Cervical Vertebrae/injuries , Cervical Vertebrae/surgery , Joint Dislocations/surgery , Occipital Bone/injuries , Occipital Bone/surgery , Cervical Vertebrae/diagnostic imaging , Child , Humans , Joint Dislocations/diagnostic imaging , Occipital Bone/diagnostic imaging
18.
Childs Nerv Syst ; 34(7): 1361-1365, 2018 07.
Article in English | MEDLINE | ID: mdl-29564537

ABSTRACT

PURPOSE: In traumatic brain injury (TBI), hyperglycemia and hypothermia are thought to be associated with poor outcomes, but have not been systematically studied in children. Thus, our aim was to evaluate whether serum glucose and temperature at admission, among other clinical variables, were associated with need for post hospital-discharge seizure medication in children diagnosed with TBI. METHODS: We performed a retrospective study of 1814 children who were diagnosed with TBI at a tertiary pediatric hospital. Serum glucose levels at admission and temperature at initial presentation, 12, and 24 h were collected. Ongoing seizure activity was defined as discharge prescription of a seizure-modifying medication. RESULTS: We identified 121 patients with need for continued seizure medications, and 80 patients expired. Independent predictors of prolonged seizures included serum glucose levels above 140 mg/dl (p < 0.003) and 199 mg/dl (p < 0.001), hypothermia (<35 °C), subdural hematoma (p < 0.001), midline shift (p < 0.001), and > 1% temperature change in the first 24 h (p < 0.001). Multivariate regression adjusting for GCS revealed that bilateral bleed (p = 0.008), body-temperature instability (p = 0.026), subdural hematoma (p < 0.001), and mechanism of injury (p = 0.007) were predictive of prolonged seizure activity. CONCLUSIONS: In summary, we conclude that body temperature may be playing a more significant role than glycemic control in propensity for ongoing seizure activity in children sustaining TBI.


Subject(s)
Brain Injuries, Traumatic/complications , Hyperglycemia/complications , Hypothermia/complications , Seizures/etiology , Adolescent , Blood Glucose/analysis , Child , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Male , Retrospective Studies , Risk Factors
19.
Neurosurg Focus ; 45(5): E4, 2018 11 01.
Article in English | MEDLINE | ID: mdl-30453458

ABSTRACT

OBJECTIVEPrognostication and surgical planning for WHO grade I versus grade II meningioma requires thoughtful decision-making based on radiographic evidence, among other factors. Although conventional statistical models such as logistic regression are useful, machine learning (ML) algorithms are often more predictive, have higher discriminative ability, and can learn from new data. The authors used conventional statistical models and an array of ML algorithms to predict atypical meningioma based on radiologist-interpreted preoperative MRI findings. The goal of this study was to compare the performance of ML algorithms to standard statistical methods when predicting meningioma grade.METHODSThe cohort included patients aged 18-65 years with WHO grade I (n = 94) and II (n = 34) meningioma in whom preoperative MRI was obtained between 1998 and 2010. A board-certified neuroradiologist, blinded to histological grade, interpreted all MR images for tumor volume, degree of peritumoral edema, presence of necrosis, tumor location, presence of a draining vein, and patient sex. The authors trained and validated several binary classifiers: k-nearest neighbors models, support vector machines, naïve Bayes classifiers, and artificial neural networks as well as logistic regression models to predict tumor grade. The area under the curve-receiver operating characteristic curve was used for comparison across and within model classes. All analyses were performed in MATLAB using a MacBook Pro.RESULTSThe authors included 6 preoperative imaging and demographic variables: tumor volume, degree of peritumoral edema, presence of necrosis, tumor location, patient sex, and presence of a draining vein to construct the models. The artificial neural networks outperformed all other ML models across the true-positive versus false-positive (receiver operating characteristic) space (area under curve = 0.8895).CONCLUSIONSML algorithms are powerful computational tools that can predict meningioma grade with great accuracy.


Subject(s)
Machine Learning , Magnetic Resonance Imaging/methods , Meningeal Neoplasms/diagnostic imaging , Meningioma/diagnostic imaging , Adult , Cohort Studies , Female , Humans , Machine Learning/standards , Magnetic Resonance Imaging/standards , Male , Middle Aged , Neoplasm Grading/methods , Neoplasm Grading/standards , Retrospective Studies
20.
Neurosurg Focus ; 45(5): E2, 2018 11 01.
Article in English | MEDLINE | ID: mdl-30453455

ABSTRACT

OBJECTIVEModern surgical planning and prognostication requires the most accurate outcomes data to practice evidence-based medicine. For clinicians treating children following traumatic brain injury (TBI) these data are severely lacking. The first aim of this study was to assess published CT classification systems in the authors' pediatric cohort. A pediatric-specific machine-learning algorithm called an artificial neural network (ANN) was then created that robustly outperformed traditional CT classification systems in predicting TBI outcomes in children.METHODSThe clinical records of children under the age of 18 who suffered a TBI and underwent head CT within 24 hours after TBI (n = 565) were retrospectively reviewed.RESULTS"Favorable" outcome (alive with Glasgow Outcome Scale [GOS] score ≥ 4 at 6 months postinjury, n = 533) and "unfavorable" outcome (death at 6 months or GOS score ≤ 3 at 6 months postinjury, n = 32) were used as the primary outcomes. The area under the receiver operating characteristic (ROC) curve (AUC) was used to delineate the strength of each CT grading system in predicting survival (Helsinki, 0.814; Rotterdam, 0.838; and Marshall, 0.781). The AUC for CT score in predicting GOS score ≤ 3, a measure of overall functionality, was similarly predictive (Helsinki, 0.717; Rotterdam, 0.748; and Marshall, 0.663). An ANN was then constructed that was able to predict 6-month outcomes with profound accuracy (AUC = 0.9462 ± 0.0422).CONCLUSIONSThis study showed that machine-learning can be leveraged to more accurately predict TBI outcomes in children.


Subject(s)
Brain Injuries, Traumatic/classification , Brain Injuries, Traumatic/diagnosis , Electronic Health Records/classification , International Classification of Diseases , Machine Learning/classification , Models, Statistical , Adolescent , Child , Child, Preschool , Electronic Health Records/standards , Electronic Health Records/trends , Female , Humans , Infant , Infant, Newborn , International Classification of Diseases/standards , International Classification of Diseases/trends , Machine Learning/standards , Male , Time Factors , Treatment Outcome
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