31 results on '"David D. Limbrick"'
Search Results
2. Cognition and Brain System Segregation in Pediatric Brain Tumor Patients Treated with Proton Therapy
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Anna V. Dowling, BS, Benjamin A. Seitzman, PhD, Timothy J. Mitchell, PhD, Michael Olufawo, BS, Donna L. Dierker, BS, Hari Anandarajah, BS, Ally Dworetsky, BS, Alana McMichael, MA, Catherine Jiang, BS, Dennis L. Barbour, MD, PhD, Bradley L. Schlaggar, MD, PhD, David D. Limbrick, MD, PhD, Jennifer M. Strahle, MD, Joshua B. Rubin, MD, PhD, Joshua S. Shimony, MD, PhD, and Stephanie M. Perkins, MD
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proton therapy ,neurocognitive ,resting state ,brain tumor ,late effects ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 ,Nuclear and particle physics. Atomic energy. Radioactivity ,QC770-798 - Abstract
Purpose: Pediatric brain tumor patients often experience significant cognitive sequelae. Resting-state functional MRI (rsfMRI) provides a measure of brain network organization, and we hypothesize that pediatric brain tumor patients treated with proton therapy will demonstrate abnormal brain network architecture related to cognitive outcome and radiation dosimetry. Participants and Methods: Pediatric brain tumor patients treated with proton therapy were enrolled on a prospective study of cognitive assessment using the NIH Toolbox Cognitive Domain. rsfMRI was obtained in participants able to complete unsedated MRI. Brain system segregation (BSS), a measure of brain network architecture, was calculated for the whole brain, the high-level cognition association systems, and the sensory-motor systems. Results: Twenty-six participants were enrolled in the study for cognitive assessment, and 18 completed rsfMRI. There were baseline cognitive deficits in attention and inhibition and processing speed prior to radiation with worsening performance over time in multiple domains. Average BSS across the whole brain was significantly decreased in participants compared with healthy controls (1.089 and 1.101, respectively; P = 0.001). Average segregation of association systems was significantly lower in participants than in controls (P
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- 2023
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3. Outcomes of the 2019 hydrocephalus association workshop, 'Driving common pathways: extending insights from posthemorrhagic hydrocephalus'
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Jason K. Karimy, Jessie C. Newville, Cameron Sadegh, Jill A. Morris, Edwin S. Monuki, David D. Limbrick, James P. McAllister II, Jenna E. Koschnitzky, Maria K. Lehtinen, and Lauren L. Jantzie
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Hydrocephalus ,Posthemorrhagic ,Post-infectious ,Intraventricular hemorrhage ,Germinal matrix hemorrhage ,Cilia ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Abstract The Hydrocephalus Association (HA) workshop, Driving Common Pathways: Extending Insights from Posthemorrhagic Hydrocephalus, was held on November 4 and 5, 2019 at Washington University in St. Louis. The workshop brought together a diverse group of basic, translational, and clinical scientists conducting research on multiple hydrocephalus etiologies with select outside researchers. The main goals of the workshop were to explore areas of potential overlap between hydrocephalus etiologies and identify drug targets that could positively impact various forms of hydrocephalus. This report details the major themes of the workshop and the research presented on three cell types that are targets for new hydrocephalus interventions: choroid plexus epithelial cells, ventricular ependymal cells, and immune cells (macrophages and microglia).
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- 2023
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4. The effect of A1 and A2 reactive astrocyte expression on hydrocephalus shunt failure
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Fatemeh Khodadadei, Rooshan Arshad, Diego M. Morales, Jacob Gluski, Neena I. Marupudi, James P. McAllister, David D. Limbrick, and Carolyn A. Harris
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Neuroprosthetic device failure ,Hydrocephalus ,Glial Scar ,A1 and A2 reactive astrocyte phenotype ,Targeted drug delivery ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Abstract Background The composition of tissue obstructing neuroprosthetic devices is largely composed of inflammatory cells with a significant astrocyte component. In a first-of-its-kind study, we profile the astrocyte phenotypes present on hydrocephalus shunts. Methods qPCR and RNA in-situ hybridization were used to quantify pro-inflammatory (A1) and anti-inflammatory (A2) reactive astrocyte phenotypes by analyzing C3 and EMP1 genes, respectively. Additionally, CSF cytokine levels were quantified using ELISA. In an in vitro model of astrocyte growth on shunts, different cytokines were used to prevent the activation of resting astrocytes into the A1 and A2 phenotypes. Obstructed and non-obstructed shunts were characterized based on the degree of actual tissue blockage on the shunt surface instead of clinical diagnosis. Results The results showed a heterogeneous population of A1 and A2 reactive astrocytes on the shunts with obstructed shunts having a significantly higher proportion of A2 astrocytes compared to non-obstructed shunts. In addition, the pro-A2 cytokine IL-6 inducing proliferation of astrocytes was found at higher concentrations among CSF from obstructed samples. Consequently, in the in vitro model of astrocyte growth on shunts, cytokine neutralizing antibodies were used to prevent activation of resting astrocytes into the A1 and A2 phenotypes which resulted in a significant reduction in both A1 and A2 growth. Conclusions Therefore, targeting cytokines involved with astrocyte A1 and A2 activation is a promising intervention aimed to prevent shunt obstruction.
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- 2022
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5. A Refined, Controlled 16S rRNA Gene Sequencing Approach Reveals Limited Detection of Cerebrospinal Fluid Microbiota in Children with Bacterial Meningitis
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Christopher E. Pope, Kathryn B. Whitlock, Paul Hodor, David D. Limbrick, Patrick J. McDonald, Jason Hauptman, Lucas R. Hoffman, and Tamara D. Simon
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bacterial meningitis ,cerebrospinal fluid ,high-throughput sequencing ,Microbiology ,QR1-502 - Abstract
ABSTRACT Advances in both laboratory and computational components of high-throughput 16S amplicon sequencing (16S HTS) have markedly increased its sensitivity and specificity. Additionally, these refinements have better delineated the limits of sensitivity, and contributions of contamination to these limits, for 16S HTS that are particularly relevant for samples with low bacterial loads, such as human cerebrospinal fluid (CSF). The objectives of this work were to (i) optimize the performance of 16S HTS in CSF samples with low bacterial loads by defining and addressing potential sources of error, and (ii) perform refined 16S HTS on CSF samples from children diagnosed with bacterial meningitis and compare results with those from microbiological cultures. Several bench and computational approaches were taken to address potential sources of error for low bacterial load samples. We compared DNA yields and sequencing results after applying three different DNA extraction approaches to an artificially constructed mock-bacterial community. We also compared two postsequencing computational contaminant removal strategies, decontam R and full contaminant sequence removal. All three extraction techniques followed by decontam R yielded similar results for the mock community. We then applied these methods to 22 CSF samples from children diagnosed with meningitis, which has low bacterial loads relative to other clinical infection samples. The refined 16S HTS pipelines identified the cultured bacterial genus as the dominant organism for only 3 of these samples. We found that all three DNA extraction techniques followed by decontam R generated similar DNA yields for mock communities at the low bacterial loads representative of CSF samples. However, the limits of detection imposed by reagent contaminants and methodologic bias precluded the accurate detection of bacteria in CSF from children with culture-confirmed meningitis using these approaches, despite rigorous controls and sophisticated computational approaches. Although we did not find current DNA-based diagnostics to be useful for pediatric meningitis samples, the utility of these methods for CSF shunt infection remains undefined. Future advances in sample processing methods to minimize or eliminate contamination will be required to improve the sensitivity and specificity of these methods for pediatric meningitis. IMPORTANCE Advances in both laboratory and computational components of high-throughput 16S amplicon sequencing (16S HTS) have markedly increased its sensitivity and specificity. These refinements have better delineated the limits of sensitivity, and contributions of contamination to these limits, for 16S HTS that are particularly relevant for samples with low bacterial loads such as human cerebrospinal fluid (CSF). The objectives of this work were to (i) optimize the performance of 16S HTS in CSF samples by defining and addressing potential sources of error, and (ii) perform refined 16S HTS on CSF samples from children diagnosed with bacterial meningitis and compare results with those from microbiological cultures. We found that the limits of detection imposed by reagent contaminants and methodologic bias precluded the accurate detection of bacteria in CSF from children with culture-confirmed meningitis using these approaches, despite rigorous controls and sophisticated computational approaches.
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- 2023
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6. Acquired hydrocephalus is associated with neuroinflammation, progenitor loss, and cellular changes in the subventricular zone and periventricular white matter
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Maria Garcia-Bonilla, Leandro Castaneyra-Ruiz, Sarah Zwick, Michael Talcott, Ayodamola Otun, Albert M. Isaacs, Diego M. Morales, David D. Limbrick, and James P. McAllister
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Kaolin-induced hydrocephalus ,Pig model ,Ventriculomegaly ,Subventricular zone reduction ,White matter alteration ,Neuroinflammation ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Abstract Background Hydrocephalus is a neurological disease with an incidence of 80–125 per 100,000 births in the United States. Neuropathology comprises ventriculomegaly, periventricular white matter (PVWM) alterations, inflammation, and gliosis. We hypothesized that hydrocephalus in a pig model is associated with subventricular and PVWM cellular alterations and neuroinflammation that could mimic the neuropathology described in hydrocephalic infants. Methods Hydrocephalus was induced by intracisternal kaolin injections in 35-day old female pigs (n = 7 for tissue analysis, n = 10 for CSF analysis). Age-matched sham controls received saline injections (n = 6). After 19–40 days, MRI scanning was performed to measure the ventricular volume. Stem cell proliferation was studied in the Subventricular Zone (SVZ), and cell death and oligodendrocytes were examined in the PVWM. The neuroinflammatory reaction was studied by quantifying astrocytes and microglial cells in the PVWM, and inflammatory cytokines in the CSF. Results The expansion of the ventricles was especially pronounced in the body of the lateral ventricle, where ependymal disruption occurred. PVWM showed a 44% increase in cell death and a 67% reduction of oligodendrocytes. In the SVZ, the number of proliferative cells and oligodendrocyte decreased by 75% and 57% respectively. The decrease of the SVZ area correlated significantly with ventricular volume increase. Neuroinflammation occurred in the hydrocephalic pigs with a significant increase of astrocytes and microglia in the PVWM, and high levels of inflammatory interleukins IL-6 and IL-8 in the CSF. Conclusion The induction of acquired hydrocephalus produced alterations in the PVWM, reduced cell proliferation in the SVZ, and neuroinflammation.
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- 2022
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7. Characterization of cerebrospinal fluid (CSF) microbiota at the time of initial surgical intervention for children with hydrocephalus
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Shailly Pandey, Kathryn B. Whitlock, Matthew R. Test, Paul Hodor, Christopher E. Pope, David D. Limbrick, Patrick J. McDonald, Jason S. Hauptman, Lucas R. Hoffman, and Tamara D. Simon
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Medicine ,Science - Abstract
Objective To characterize the microbiota of the cerebrospinal fluid (CSF) from children with hydrocephalus at the time of initial surgical intervention. Study design CSF was obtained at initial surgical intervention. One aliquot was stored in skim milk-tryptone-glucose-glycerol (STGG) medium and the second was unprocessed; both were then stored at –70°C. Bacterial growth for CSF samples stored in STGG were subsequently characterized using aerobic and anaerobic culture on blood agar and MALDI-TOF sequencing. All unprocessed CSF samples underwent 16S quantitative polymerase chain reaction (qPCR) sequencing, and a subset underwent standard clinical microbiological culture. CSF with culture growth (either after storage in STGG or standard clinical) were further analyzed using whole-genome amplification sequencing (WGAS). Results 11/66 (17%) samples stored in STGG and 1/36 (3%) that underwent standard clinical microbiological culture demonstrated bacterial growth. Of the organisms present, 8 were common skin flora and 4 were potential pathogens; only 1 was also qPCR positive. WGAS findings and STGG culture findings were concordant for only 1 sample, identifying Staphylococcus epidermidis. No significant difference in time to second surgical intervention was observed between the STGG culture-positive and negative groups. Conclusion(s) Using high sensitivity methods, we detected the presence of bacteria in a subset of CSF samples at the time of first surgery. Therefore, the true presence of bacteria in CSF of children with hydrocephalus cannot be ruled out, though our findings may suggest these bacteria are contaminants or false positives of the detection methods. Regardless of origin, the detection of microbiota in the CSF of these children may not have any clinical significance.
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- 2023
8. Biochemical profile of human infant cerebrospinal fluid in intraventricular hemorrhage and post-hemorrhagic hydrocephalus of prematurity
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Ayodamola Otun, Diego M. Morales, Maria Garcia-Bonilla, Seth Goldberg, Leandro Castaneyra-Ruiz, Yan Yan, Albert M. Isaacs, Jennifer M. Strahle, James P. McAllister, and David D. Limbrick
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Post-hemorrhagic hydrocephalus (PHH) ,Intraventricular hemorrhage (IVH) ,CSF osmolality ,CSF electrolytes ,Cerebrospinal fluid (CSF) ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Abstract Background Intraventricular hemorrhage (IVH) and post-hemorrhagic hydrocephalus (PHH) have a complex pathophysiology involving inflammatory response, ventricular zone and cell–cell junction disruption, and choroid-plexus (ChP) hypersecretion. Increased cerebrospinal fluid (CSF) cytokines, extracellular matrix proteins, and blood metabolites have been noted in IVH/PHH, but osmolality and electrolyte disturbances have not been evaluated in human infants with these conditions. We hypothesized that CSF total protein, osmolality, electrolytes, and immune cells increase in PHH. Methods CSF samples were obtained from lumbar punctures of control infants and infants with IVH prior to the development of PHH and any neurosurgical intervention. Osmolality, total protein, and electrolytes were measured in 52 infants (18 controls, 10 low grade (LG) IVH, 13 high grade (HG) IVH, and 11 PHH). Serum electrolyte concentrations, and CSF and serum cell counts within 1-day of clinical sampling were obtained from clinical charts. Frontal occipital horn ratio (FOR) was measured for estimating the degree of ventriculomegaly. Dunn or Tukey’s post-test ANOVA analysis were used for pair-wise comparisons. Results CSF osmolality, sodium, potassium, and chloride were elevated in PHH compared to control (p = 0.012 −
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- 2021
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9. Type IV Pili Are a Critical Virulence Factor in Clinical Isolates of Paenibacillus thiaminolyticus
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Christine Hehnly, Aiqin Shi, Paddy Ssentongo, Lijun Zhang, Albert Isaacs, Sarah U. Morton, Nicholas Streck, Petra Erdmann-Gilmore, Igor Tolstoy, R. Reid Townsend, David D. Limbrick, Joseph N. Paulson, Jessica E. Ericson, Michael Y. Galperin, Steven J. Schiff, and James R. Broach
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Paenibacillus thiaminolyticus ,postinfectious hydrocephalus ,type IV pilus ,virulence factors ,Microbiology ,QR1-502 - Abstract
ABSTRACT Hydrocephalus, the leading indication for childhood neurosurgery worldwide, is particularly prevalent in low- and middle-income countries. Hydrocephalus preceded by an infection, or postinfectious hydrocephalus, accounts for up to 60% of hydrocephalus in these areas. Since many children with hydrocephalus suffer poor long-term outcomes despite surgical intervention, prevention of hydrocephalus remains paramount. Our previous studies implicated a novel bacterial pathogen, Paenibacillus thiaminolyticus, as a causal agent of neonatal sepsis and postinfectious hydrocephalus in Uganda. Here, we report the isolation of three P. thiaminolyticus strains, Mbale, Mbale2, and Mbale3, from patients with postinfectious hydrocephalus. We constructed complete genome assemblies of the clinical isolates as well as the nonpathogenic P. thiaminolyticus reference strain and performed comparative genomic and proteomic analyses to identify potential virulence factors. All three isolates carry a unique beta-lactamase gene, and two of the three isolates exhibit resistance in culture to the beta-lactam antibiotics penicillin and ampicillin. In addition, a cluster of genes carried on a mobile genetic element that encodes a putative type IV pilus operon is present in all three clinical isolates but absent in the reference strain. CRISPR-mediated deletion of the gene cluster substantially reduced the virulence of the Mbale strain in mice. Comparative proteogenomic analysis identified various additional potential virulence factors likely acquired on mobile genetic elements in the virulent strains. These results provide insight into the emergence of virulence in P. thiaminolyticus and suggest avenues for the diagnosis and treatment of this novel bacterial pathogen. IMPORTANCE Postinfectious hydrocephalus, a devastating sequela of neonatal infection, is associated with increased childhood mortality and morbidity. A novel bacterial pathogen, Paenibacillus thiaminolyticus, is highly associated with postinfectious hydrocephalus in an African cohort. Whole-genome sequencing, RNA sequencing, and proteomics of clinical isolates and a reference strain in combination with CRISPR editing identified type IV pili as a critical virulence factor for P. thiaminolyticus infection. Acquisition of a type IV pilus-encoding mobile genetic element critically contributed to converting a nonpathogenic strain of P. thiaminolyticus into a pathogen capable of causing devastating diseases. Given the widespread presence of type IV pilus in pathogens, the presence of the type IV pilus operon could serve as a diagnostic and therapeutic target in P. thiaminolyticus and related bacteria.
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- 2022
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10. A novel model of acquired hydrocephalus for evaluation of neurosurgical treatments
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James P. McAllister, Michael R. Talcott, Albert M. Isaacs, Sarah H. Zwick, Maria Garcia-Bonilla, Leandro Castaneyra-Ruiz, Alexis L. Hartman, Ryan N. Dilger, Stephen A. Fleming, Rebecca K. Golden, Diego M. Morales, Carolyn A. Harris, and David D. Limbrick
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Hydrocephalus ,Animal models ,Kaolin ,Acquired hydrocephalus ,Shunt ,Ventriculomegaly ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Abstract Background Many animal models have been used to study the pathophysiology of hydrocephalus; most of these have been rodent models whose lissencephalic cerebral cortex may not respond to ventriculomegaly in the same way as gyrencephalic species and whose size is not amenable to evaluation of clinically relevant neurosurgical treatments. Fewer models of hydrocephalus in gyrencephalic species have been used; thus, we have expanded upon a porcine model of hydrocephalus in juvenile pigs and used it to explore surgical treatment methods. Methods Acquired hydrocephalus was induced in 33–41-day old pigs by percutaneous intracisternal injections of kaolin (n = 17). Controls consisted of sham saline-injected (n = 6) and intact (n = 4) animals. Magnetic resonance imaging (MRI) was employed to evaluate ventriculomegaly at 11–42 days post-kaolin and to plan the surgical implantation of ventriculoperitoneal shunts at 14–38-days post-kaolin. Behavioral and neurological status were assessed. Results Bilateral ventriculomegaly occurred post-induction in all regions of the cerebral ventricles, with prominent CSF flow voids in the third ventricle, foramina of Monro, and cerebral aqueduct. Kaolin deposits formed a solid cast in the basal cisterns but the cisterna magna was patent. In 17 untreated hydrocephalic animals. Mean total ventricular volume was 8898 ± 5917 SD mm3 at 11–43 days of age, which was significantly larger than the baseline values of 2251 ± 194 SD mm3 for 6 sham controls aged 45–55 days, (p
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- 2021
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11. Electronic clinical decision support for children with minor head trauma and intracranial injuries: a sociotechnical analysis
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Jacob K. Greenberg, Ayodamola Otun, Azzah Nasraddin, Ross C. Brownson, Nathan Kuppermann, David D. Limbrick, Po-Yin Yen, and Randi E. Foraker
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Sociotechnical analysis ,Traumatic brain injury ,Head trauma ,Electronic clinical decision support ,Implementation science ,Health information technology ,Computer applications to medicine. Medical informatics ,R858-859.7 - Abstract
Abstract Background Current management of children with minor head trauma (MHT) and intracranial injuries is not evidence-based and may place some children at risk of harm. Evidence-based electronic clinical decision support (CDS) for management of these children may improve patient safety and decrease resource use. To guide these efforts, we evaluated the sociotechnical environment impacting the implementation of electronic CDS, including workflow and communication, institutional culture, and hardware and software infrastructure, among other factors. Methods Between March and May, 2020 semi-structured qualitative focus group interviews were conducted to identify sociotechnical influences on CDS implementation. Physicians from neurosurgery, emergency medicine, critical care, and pediatric general surgery were included, along with information technology specialists. Participants were recruited from nine health centers in the United States. Focus group transcripts were coded and analyzed using thematic analysis. The final themes were then cross-referenced with previously defined sociotechnical dimensions. Results We included 28 physicians and four information technology specialists in seven focus groups (median five participants per group). Five physicians were trainees and 10 had administrative leadership positions. Through inductive thematic analysis, we identified five primary themes: (1) clinical impact; (2) stakeholders and users; (3) tool content; (4) clinical practice integration; and (5) post-implementation evaluation measures. Participants generally supported using CDS to determine an appropriate level-of-care for these children. However, some had mixed feelings regarding how the tool could best be used by different specialties (e.g. use by neurosurgeons versus non-neurosurgeons). Feedback from the interviews helped refine the tool content and also highlighted potential technical and workflow barriers to address prior to implementation. Conclusions We identified key factors impacting the implementation of electronic CDS for children with MHT and intracranial injuries. These results have informed our implementation strategy and may also serve as a template for future efforts to implement health information technology in a multidisciplinary, emergency setting.
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- 2021
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12. Generation of Periventricular Reactive Astrocytes Overexpressing Aquaporin 4 Is Stimulated by Mesenchymal Stem Cell Therapy
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María García-Bonilla, Betsaida Ojeda-Pérez, Kirill Shumilov, Luis-Manuel Rodríguez-Pérez, Dolores Domínguez-Pinos, Javier Vitorica, Sebastián Jiménez, Reposo Ramírez-Lorca, Miriam Echevarría, Casimiro Cárdenas-García, Teresa Iglesias, Antonia Gutiérrez, James P. McAllister, David D. Limbrick, Patricia Páez-González, and Antonio J. Jiménez
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hydrocephalus ,aquaporin 4 ,astrocyte reaction ,mesenchymal stem cell ,stem cell therapy ,proteomic ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Aquaporin-4 (AQP4) plays a crucial role in brain water circulation and is considered a therapeutic target in hydrocephalus. Congenital hydrocephalus is associated with a reaction of astrocytes in the periventricular white matter both in experimental models and human cases. A previous report showed that bone marrow-derived mesenchymal stem cells (BM-MSCs) transplanted into the lateral ventricles of hyh mice exhibiting severe congenital hydrocephalus are attracted by the periventricular astrocyte reaction, and the cerebral tissue displays recovery. The present investigation aimed to test the effect of BM-MSC treatment on astrocyte reaction formation. BM-MSCs were injected into the lateral ventricles of four-day-old hyh mice, and the periventricular reaction was detected two weeks later. A protein expression analysis of the cerebral tissue differentiated the BM-MSC-treated mice from the controls and revealed effects on neural development. In in vivo and in vitro experiments, BM-MSCs stimulated the generation of periventricular reactive astrocytes overexpressing AQP4 and its regulatory protein kinase D-interacting substrate of 220 kDa (Kidins220). In the cerebral tissue, mRNA overexpression of nerve growth factor (NGF), vascular endothelial growth factor (VEGF), hypoxia-inducible factor-1 (HIF1α), and transforming growth factor beta 1 (TGFβ1) could be related to the regulation of the astrocyte reaction and AQP4 expression. In conclusion, BM-MSC treatment in hydrocephalus can stimulate a key developmental process such as the periventricular astrocyte reaction, where AQP4 overexpression could be implicated in tissue recovery.
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- 2023
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13. Cerebrospinal fluid biomarkers of neuroinflammation in children with hydrocephalus and shunt malfunction
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Carolyn A. Harris, Diego M. Morales, Rooshan Arshad, James P. McAllister, and David D. Limbrick
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Neuroinflammation ,Cytokines ,Mmps ,Hydrocephalus ,Revisions ,Multiplex ELISA ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Abstract Background Approximately 30% of cerebrospinal fluid (CSF) shunt systems for hydrocephalus fail within the first year and 98% of all patients will have shunt failure in their lifetime. Obstruction remains the most common reason for shunt failure. Previous evidence suggests elevated pro-inflammatory cytokines in CSF are associated with worsening clinical outcomes in neuroinflammatory diseases. The aim of this study was to determine whether cytokines and matrix metalloproteinases (MMPs) contribute towards shunt failure in hydrocephalus. Methods Using multiplex ELISA, this study examined shunt failure through the CSF protein concentration profiles of select pro-inflammatory and anti-inflammatory cytokines, as well as select MMPs. Interdependencies such as the past number of previous revisions, length of time implanted, patient age, and obstruction or non-obstruction revision were examined. The pro-inflammatory cytokines were IL-1β, IL-2, IL-5, IL-6, IL-8, IL-12, IL-17, TNF-α, GM-CSF, IFN-γ. The anti-inflammatory cytokines were IL-4 and IL-10, and the MMPs were MMP-2, MMP-3, MMP-7, MMP-9. Protein concentration is reported as pg/mL for each analyte. Results Patient CSF was obtained at the time of shunt revision operation; all pediatric (
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- 2021
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14. Robust deep learning classification of adamantinomatous craniopharyngioma from limited preoperative radiographic images
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Eric W. Prince, Ros Whelan, David M. Mirsky, Nicholas Stence, Susan Staulcup, Paul Klimo, Richard C. E. Anderson, Toba N. Niazi, Gerald Grant, Mark Souweidane, James M. Johnston, Eric M. Jackson, David D. Limbrick, Amy Smith, Annie Drapeau, Joshua J. Chern, Lindsay Kilburn, Kevin Ginn, Robert Naftel, Roy Dudley, Elizabeth Tyler-Kabara, George Jallo, Michael H. Handler, Kenneth Jones, Andrew M. Donson, Nicholas K. Foreman, and Todd C. Hankinson
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Medicine ,Science - Abstract
Abstract Deep learning (DL) is a widely applied mathematical modeling technique. Classically, DL models utilize large volumes of training data, which are not available in many healthcare contexts. For patients with brain tumors, non-invasive diagnosis would represent a substantial clinical advance, potentially sparing patients from the risks associated with surgical intervention on the brain. Such an approach will depend upon highly accurate models built using the limited datasets that are available. Herein, we present a novel genetic algorithm (GA) that identifies optimal architecture parameters using feature embeddings from state-of-the-art image classification networks to identify the pediatric brain tumor, adamantinomatous craniopharyngioma (ACP). We optimized classification models for preoperative Computed Tomography (CT), Magnetic Resonance Imaging (MRI), and combined CT and MRI datasets with demonstrated test accuracies of 85.3%, 83.3%, and 87.8%, respectively. Notably, our GA improved baseline model performance by up to 38%. This work advances DL and its applications within healthcare by identifying optimized networks in small-scale data contexts. The proposed system is easily implementable and scalable for non-invasive computer-aided diagnosis, even for uncommon diseases.
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- 2020
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15. Preterm intraventricular hemorrhage in vitro: modeling the cytopathology of the ventricular zone
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Leandro Castaneyra-Ruiz, James P. McAllister, Diego M. Morales, Steven L. Brody, Albert M. Isaacs, and David D. Limbrick
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Cell culture ,Neural stem cells ,Ependyma ,Ventricular zone ,Intraventricular hemorrhage ,Post- hemorrhagic hydrocephalus ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Abstract Background Severe intraventricular hemorrhage (IVH) is one of the most devastating neurological complications in preterm infants, with the majority suffering long-term neurological morbidity and up to 50% developing post-hemorrhagic hydrocephalus (PHH). Despite the importance of this disease, its cytopathological mechanisms are not well known. An in vitro model of IVH is required to investigate the effects of blood and its components on the developing ventricular zone (VZ) and its stem cell niche. To address this need, we developed a protocol from our accepted in vitro model to mimic the cytopathological conditions of IVH in the preterm infant. Methods Maturing neuroepithelial cells from the VZ were harvested from the entire lateral ventricles of wild type C57BL/6 mice at 1–4 days of age and expanded in proliferation media for 3–5 days. At confluence, cells were re-plated onto 24-well plates in differentiation media to generate ependymal cells (EC). At approximately 3–5 days, which corresponded to the onset of EC differentiation based on the appearance of multiciliated cells, phosphate-buffered saline for controls or syngeneic whole blood for IVH was added to the EC surface. The cells were examined for the expression of EC markers of differentiation and maturation to qualitatively and quantitatively assess the effect of blood exposure on VZ transition from neuroepithelial cells to EC. Discussion This protocol will allow investigators to test cytopathological mechanisms contributing to the pathology of IVH with high temporal resolution and query the impact of injury to the maturation of the VZ. This technique recapitulates features of normal maturation of the VZ in vitro, offering the capacity to investigate the developmental features of VZ biogenesis.
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- 2020
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16. Characterization of a multicenter pediatric-hydrocephalus shunt biobank
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Jacob Gluski, Paul Zajciw, Prashant Hariharan, Amanda Morgan, Diego M. Morales, Andrew Jea, William Whitehead, Neena Marupudi, Steven Ham, Sandeep Sood, James P. McAllister, David D. Limbrick, and Carolyn A. Harris
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Hydrocephalus ,Biobank ,Shunt failure ,Shunt obstruction ,CSF = cerebrospinal fluid ,Ventriculoperitoneal shunt ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Abstract Background Pediatric hydrocephalus is a devastating and costly disease. The mainstay of treatment is still surgical shunting of cerebrospinal fluid (CSF). These shunts fail at a high rate and impose a significant burden on patients, their families and society. The relationship between clinical decision making and shunt failure is poorly understood and multifaceted, but catheter occlusion remains the most frequent cause of shunt complications. In order to investigate factors that affect shunt failure, we have established the Wayne State University (WSU) shunt biobank. Methods To date, four hospital centers have contributed various components of failed shunts and CSF from patients diagnosed with hydrocephalus before adulthood. The hardware samples are transported in paraformaldehyde and transferred to phosphate-buffered saline with sodium azide upon deposit into the biobank. Once in the bank, they are then available for study. Informed consent is obtained by the local center before corresponding clinical data are entered into a REDCap database. Data such as hydrocephalus etiology and details of shunt revision history. All data are entered under a coded identifier. Results 293 shunt samples were collected from 228 pediatric patients starting from May 2015 to September 2019. We saw a significant difference in the number of revisions per patient between centers (Kruskal–Wallis H test, p value
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- 2020
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17. Transcriptional analyses of adult and pediatric adamantinomatous craniopharyngioma reveals similar expression signatures regarding potential therapeutic targets
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Eric Prince, Ros Whelan, Andrew Donson, Susan Staulcup, Astrid Hengartner, Trinka Vijmasi, Chibueze Agwu, Kevin O. Lillehei, Nicholas K. Foreman, James M. Johnston, Luca Massimi, Richard C. E. Anderson, Mark M. Souweidane, Robert P. Naftel, David D. Limbrick, Gerald Grant, Toba N. Niazi, Roy Dudley, Lindsay Kilburn, Eric M. Jackson, George I. Jallo, Kevin Ginn, Amy Smith, Joshua J. Chern, Amy Lee, Annie Drapeau, Mark D. Krieger, Michael H. Handler, Todd C. Hankinson, and on behalf of the Advancing Treatment for Pediatric Craniopharyngioma Consortium
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Adamantinomatous Craniopharyngioma ,Transcriptional analysis ,Age-related therapy ,Pediatric Craniopharyngioma ,Suprasellar tumor ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Abstract Adamantinomatous craniopharyngioma (ACP) is a biologically benign but clinically aggressive lesion that has a significant impact on quality of life. The incidence of the disease has a bimodal distribution, with peaks occurring in children and older adults. Our group previously published the results of a transcriptome analysis of pediatric ACPs that identified several genes that were consistently overexpressed relative to other pediatric brain tumors and normal tissue. We now present the results of a transcriptome analysis comparing pediatric to adult ACP to identify biological differences between these groups that may provide novel therapeutic insights or support the assertion that potential therapies identified through the study of pediatric ACP may also have a role in adult ACP. Using our compiled transcriptome dataset of 27 pediatric and 9 adult ACPs, obtained through the Advancing Treatment for Pediatric Craniopharyngioma Consortium, we interrogated potential age-related transcriptional differences using several rigorous mathematical analyses. These included: canonical differential expression analysis; divisive, agglomerative, and probabilistic based hierarchical clustering; information theory based characterizations; and the deep learning approach, HD Spot. Our work indicates that there is no therapeutically relevant difference in ACP gene expression based on age. As such, potential therapeutic targets identified in pediatric ACP are also likely to have relvance for adult patients.
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- 2020
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18. Multi-omic analysis elucidates the genetic basis of hydrocephalus
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Andrew T. Hale, Lisa Bastarache, Diego M. Morales, John C. Wellons, III, David D. Limbrick, Jr., and Eric R. Gamazon
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PrediXcan ,human genetics ,transcriptomics ,hydrocephalus ,TWAS ,GWAS ,Biology (General) ,QH301-705.5 - Abstract
Summary: We conducted PrediXcan analysis of hydrocephalus risk in ten neurological tissues and whole blood. Decreased expression of MAEL in the brain was significantly associated (Bonferroni-adjusted p < 0.05) with hydrocephalus. PrediXcan analysis of brain imaging and genomics data in the independent UK Biobank (N = 8,428) revealed that MAEL expression in the frontal cortex is associated with white matter and total brain volumes. Among the top differentially expressed genes in brain, we observed a significant enrichment for gene-level associations with these structural phenotypes, suggesting an effect on disease risk through regulation of brain structure and integrity. We found additional support for these genes through analysis of the choroid plexus transcriptome of a murine model of hydrocephalus. Finally, differential protein expression analysis in patient cerebrospinal fluid recapitulated disease-associated expression changes in neurological tissues, but not in whole blood. Our findings provide convergent evidence highlighting the importance of tissue-specific pathways and mechanisms in the pathophysiology of hydrocephalus.
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- 2021
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19. Immune activation during Paenibacillus brain infection in African infants with frequent cytomegalovirus co-infection
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Albert M. Isaacs, Sarah U. Morton, Mercedeh Movassagh, Qiang Zhang, Christine Hehnly, Lijun Zhang, Diego M. Morales, Shamim A. Sinnar, Jessica E. Ericson, Edith Mbabazi-Kabachelor, Peter Ssenyonga, Justin Onen, Ronnie Mulondo, Mady Hornig, Benjamin C. Warf, James R. Broach, R. Reid Townsend, David D. Limbrick, Jr., Joseph N. Paulson, and Steven J. Schiff
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Immunology ,Proteomics ,Transcriptomics ,Science - Abstract
Summary: Inflammation during neonatal brain infections leads to significant secondary sequelae such as hydrocephalus, which often follows neonatal sepsis in the developing world. In 100 African hydrocephalic infants we identified the biological pathways that account for this response. The dominant bacterial pathogen was a Paenibacillus species, with frequent cytomegalovirus co-infection. A proteogenomic strategy was employed to confirm host immune response to Paenibacillus and to define the interplay within the host immune response network. Immune activation emphasized neuroinflammation, oxidative stress reaction, and extracellular matrix organization. The innate immune system response included neutrophil activity, signaling via IL-4, IL-12, IL-13, interferon, and Jak/STAT pathways. Platelet-activating factors and factors involved with microbe recognition such as Class I MHC antigen-presenting complex were also increased. Evidence suggests that dysregulated neuroinflammation propagates inflammatory hydrocephalus, and these pathways are potential targets for adjunctive treatments to reduce the hazards of neuroinflammation and risk of hydrocephalus following neonatal sepsis.
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- 2021
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20. Semi-automated segmentation of the lateral periventricular regions using diffusion magnetic resonance imaging
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Albert M. Isaacs, Rowland H. Han, Christopher D. Smyser, David D. Limbrick, Jr., and Joshua S. Shimony
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Segmentation of lateral ventricular perimeter regions of interest ,Science - Abstract
The lateral ventricular perimeter (LVP) of the brain is a critical region because in addition to housing neural stem cells required for brain development, it facilitates cerebrospinal fluid (CSF) bulk flow and functions as a blood-CSF barrier to protect periventricular white matter (PVWM) and other adjacent regions from injurious toxins. LVP injury is common, particularly among preterm infants who sustain intraventricular hemorrhage or post hemorrhagic hydrocephalus and has been associated with poor neurological outcomes. Assessment of the LVP with diffusion MRI has been challenging, primarily due to issues with partial volume artifacts since the LVP region is in close proximity to CSF and other structures of varying signal intensities that may be inadvertently included in LVP segmentation.This research method presents: • A novel MATLAB-based method to segment a homogenous LVP layer using high spatial resolution parameters (voxel size 1.2 × 1.2 × 1.2 mm3) to only capture the innermost layer of the LVP. • The segmented LVP is averaged from three contiguous axial slices to increase signal to noise ratio and reduce the effect of any residual volume averaging effect and eliminates manual and inter/intrarater-related errors.
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- 2020
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21. Opportunities in posthemorrhagic hydrocephalus research: outcomes of the Hydrocephalus Association Posthemorrhagic Hydrocephalus Workshop
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Jenna E. Koschnitzky, Richard F. Keep, David D. Limbrick, James P. McAllister, Jill A. Morris, Jennifer Strahle, and Yun C. Yung
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Hydrocephalus ,Posthemorrhagic ,Intraventricular hemorrhage ,Germinal matrix hemorrhage ,Blood brain barrier ,Premature ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Abstract The Hydrocephalus Association Posthemorrhagic Hydrocephalus Workshop was held on July 25 and 26, 2016 at the National Institutes of Health. The workshop brought together a diverse group of researchers including pediatric neurosurgeons, neurologists, and neuropsychologists with scientists in the fields of brain injury and development, cerebrospinal and interstitial fluid dynamics, and the blood–brain and blood–CSF barriers. The goals of the workshop were to identify areas of opportunity in posthemorrhagic hydrocephalus research and encourage scientific collaboration across a diverse set of fields. This report details the major themes discussed during the workshop and research opportunities identified for posthemorrhagic hydrocephalus. The primary areas include (1) preventing intraventricular hemorrhage, (2) stopping primary and secondary brain damage, (3) preventing hydrocephalus, (4) repairing brain damage, and (5) improving neurodevelopment outcomes in posthemorrhagic hydrocephalus.
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- 2018
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22. Chemokine and cytokine levels in the lumbar cerebrospinal fluid of preterm infants with post-hemorrhagic hydrocephalus
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Gakwaya Habiyaremye, Diego M. Morales, Clinton D. Morgan, James P. McAllister, Travis S. CreveCoeur, Rowland H. Han, Mohamed Gabir, Brandon Baksh, Deanna Mercer, and David D. Limbrick
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Cytokines ,Chemokines ,Post-hemorrhagic ,Hydrocephalus ,CSF ,Cerebrospinal fluid ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Abstract Background Neuroinflammation has been implicated in the pathophysiology of post-hemorrhagic hydrocephalus (PHH) of prematurity, but no comprehensive analysis of signaling molecules has been performed using human cerebrospinal fluid (CSF). Methods Lumbar CSF levels of key cytokines (IL-1α, IL-1β, IL-4, IL-6, IL-8, IL-10, IL-12, TNF-α, TGF-β1, IFN-γ) and chemokines (XCL-1, CCL-2, CCL-3, CCL-19, CXCL-10, CXCL-11, CXCL-12) were measured using conventional and multiplexed Enzyme-linked Immunosorbent Assays and compared between preterm infants with PHH and those with no known neurological injury. The relationships between individual biomarker levels and specific CSF cell counts were examined. Results Total protein (TP) CSF levels were elevated in the PHH subjects compared to controls. CSF levels of IL-1α, IL-4, IL-6, IL-12, TNF-α, CCL-3, CCL-19, and CXCL-10 were significantly increased in PHH whereas XCL-1 was significantly decreased in PHH. When normalizing by TP, IL-1α, IL-1β, IL-10, IL-12, CCL-3, and CCL-19 levels were significantly elevated compared to controls, while XCL-1 levels remained significantly decreased. Among those with significantly different levels in both absolute and normalized levels, only absolute CCL-19 levels showed a significant correlation with CSF nucleated cells, neutrophils, and lymphocytes. IL-1β and CXCL-10 also were correlated with total cell count, nucleated cells, red blood cells, and neutrophils. Conclusions Neuroinflammation is likely to be an important process in the pathophysiology of PHH. To our knowledge, this is the first study to investigate CSF levels of chemokines in PHH as well as the only one to show XCL-1 selectively decreased in a diseased state. Additionally, CCL-19 was the only analyte studied that showed significant differences between groups and had significant correlation with cell count analysis. The selectivity of CCL-19 and XCL-1 should be further investigated. Future studies will further delineate the role of these cytokines and chemokines in PHH.
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- 2017
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23. Impaired hippocampal development and outcomes in very preterm infants with perinatal brain injury
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Jennifer M. Strahle, Regina L. Triplett, Dimitrios Alexopoulos, Tara A. Smyser, Cynthia E. Rogers, David D. Limbrick, Jr, and Christopher D. Smyser
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Computer applications to medicine. Medical informatics ,R858-859.7 ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Preterm infants are at high risk for brain injury during the perinatal period. Intraventricular hemorrhage and periventricular leukomalacia, the two most common patterns of brain injury in prematurely-born children, are associated with poor neurodevelopmental outcomes. The hippocampus is known to be critical for learning and memory; however, it remains unknown how these forms of brain injury affect hippocampal growth and how the resulting alterations in hippocampal development relate to childhood outcomes. To investigate these relationships, hippocampal segmentations were performed on term equivalent MRI scans from 55 full-term infants, 85 very preterm infants (born ≤32 weeks gestation) with no to mild brain injury and 73 very preterm infants with brain injury (e.g., grade III/IV intraventricular hemorrhage, post-hemorrhagic hydrocephalus, cystic periventricular leukomalacia). Infants then underwent standardized neurodevelopmental testing using the Bayley Scales of Infant and Toddler Development, 3rd edition at age 2 years, corrected for prematurity. To delineate the effects of brain injury on early hippocampal development, hippocampal volumes were compared across groups and associations between neonatal volumes and neurodevelopmental outcomes at age 2 years were explored. Very preterm infants with brain injury had smaller hippocampal volumes at term equivalent age compared to term and very preterm infants with no to mild injury, with the smallest hippocampi among those with grade III/IV intraventricular hemorrhage and post-hemorrhagic hydrocephalus. Further, larger ventricle size was associated with smaller hippocampal size. Smaller hippocampal volumes were related to worse motor performance at age 2 years across all groups. In addition, smaller hippocampal volumes in infants with brain injury were correlated with impaired cognitive scores at age 2 years, a relationship specific to this group. Consistent with our preclinical findings, these findings demonstrate that perinatal brain injury is associated with hippocampal size in preterm infants, with smaller volumes related to domain-specific neurodevelopmental impairments in this high-risk clinical population. Keywords: Hippocampus, Very preterm infant, White matter injury, Neurodevelopment, Magnetic resonance imaging
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- 2019
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24. A comparison of resting state functional magnetic resonance imaging to invasive electrocortical stimulation for sensorimotor mapping in pediatric patients
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Jarod L. Roland, Carl D. Hacker, Abraham Z. Snyder, Joshua S. Shimony, John M. Zempel, David D. Limbrick, Matthew D. Smyth, and Eric C. Leuthardt
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Computer applications to medicine. Medical informatics ,R858-859.7 ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Localizing neurologic function within the brain remains a significant challenge in clinical neurosurgery. Invasive mapping with direct electrocortical stimulation currently is the clinical gold standard but is impractical in young or cognitively delayed patients who are unable to reliably perform tasks. Resting state functional magnetic resonance imaging non-invasively identifies resting state networks without the need for task performance, hence, is well suited to pediatric patients. We compared sensorimotor network localization by resting state fMRI to cortical stimulation sensory and motor mapping in 16 pediatric patients aged 3.1 to 18.6 years. All had medically refractory epilepsy that required invasive electrographic monitoring and stimulation mapping. The resting state fMRI data were analyzed using a previously trained machine learning classifier that has previously been evaluated in adults. We report comparable functional localization by resting state fMRI compared to stimulation mapping. These results provide strong evidence for the utility of resting state functional imaging in the localization of sensorimotor cortex across a wide range of pediatric patients. Keywords: Resting state, Functional MRI, Mapping, Pediatric, Neurosurgery
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- 2019
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25. MR diffusion changes in the perimeter of the lateral ventricles demonstrate periventricular injury in post-hemorrhagic hydrocephalus of prematurity
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Albert M. Isaacs, Christopher D. Smyser, Rachel E. Lean, Dimitrios Alexopoulos, Rowland H. Han, Jeffrey J. Neil, Sophia A. Zimbalist, Cynthia E. Rogers, Yan Yan, Joshua S. Shimony, and David D. Limbrick, Jr.
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Computer applications to medicine. Medical informatics ,R858-859.7 ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Objectives: Injury to the preterm lateral ventricular perimeter (LVP), which contains the neural stem cells responsible for brain development, may contribute to the neurological sequelae of intraventricular hemorrhage (IVH) and post-hemorrhagic hydrocephalus of prematurity (PHH). This study utilizes diffusion MRI (dMRI) to characterize the microstructural effects of IVH/PHH on the LVP and segmented frontal-occipital horn perimeters (FOHP). Study design: Prospective study of 56 full-term infants, 72 very preterm infants without brain injury (VPT), 17 VPT infants with high-grade IVH without hydrocephalus (HG-IVH), and 13 VPT infants with PHH who underwent dMRI at term equivalent. LVP and FOHP dMRI measures and ventricular size-dMRI correlations were assessed. Results: In the LVP, PHH had consistently lower FA and higher MD and RD than FT and VPT (p.050). Ventricular size correlated negatively with FA, and positively with MD and RD (p
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- 2019
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26. Left hemisphere structural connectivity abnormality in pediatric hydrocephalus patients following surgery
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Weihong Yuan, Artur Meller, Joshua S. Shimony, Tiffany Nash, Blaise V. Jones, Scott K. Holland, Mekibib Altaye, Holly Barnard, Jannel Phillips, Stephanie Powell, Robert C. McKinstry, David D. Limbrick, Akila Rajagopal, and Francesco T. Mangano
- Subjects
Diffusion tensor imaging ,Graph theoretical analysis ,Left hemisphere ,Pediatric hydrocephalus ,Small-worldness ,Computer applications to medicine. Medical informatics ,R858-859.7 ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Neuroimaging research in surgically treated pediatric hydrocephalus patients remains challenging due to the artifact caused by programmable shunt. Our previous study has demonstrated significant alterations in the whole brain white matter structural connectivity based on diffusion tensor imaging (DTI) and graph theoretical analysis in children with hydrocephalus prior to surgery or in surgically treated children without programmable shunts. This study seeks to investigate the impact of brain injury on the topological features in the left hemisphere, contratelateral to the shunt placement, which will avoid the influence of shunt artifacts and makes further group comparisons feasible for children with programmable shunt valves. Three groups of children (34 in the control group, 12 in the 3-month post-surgery group, and 24 in the 12-month post-surgery group, age between 1 and 18 years) were included in the study. The structural connectivity data processing and analysis were performed based on DTI and graph theoretical analysis. Specific procedures were revised to include only left brain imaging data in normalization, parcellation, and fiber counting from DTI tractography. Our results showed that, when compared to controls, children with hydrocephalus in both the 3-month and 12-month post-surgery groups had significantly lower normalized clustering coefficient, lower small-worldness, and higher global efficiency (all p
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- 2016
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27. Abnormal structural connectivity in the brain networks of children with hydrocephalus
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Weihong Yuan, Scott K. Holland, Joshua S. Shimony, Mekibib Altaye, Francesco T. Mangano, David D. Limbrick, Blaise V. Jones, Tiffany Nash, Akila Rajagopal, Sarah Simpson, Dustin Ragan, and Robert C. McKinstry
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Graph theoretical analysis ,Network ,Pediatric hydrocephalus ,Small-worldness ,Computer applications to medicine. Medical informatics ,R858-859.7 ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Increased intracranial pressure and ventriculomegaly in children with hydrocephalus are known to have adverse effects on white matter structure. This study seeks to investigate the impact of hydrocephalus on topological features of brain networks in children. The goal was to investigate structural network connectivity, at both global and regional levels, in the brains in children with hydrocephalus using graph theory analysis and diffusion tensor tractography. Three groups of children were included in the study (29 normally developing controls, 9 preoperative hydrocephalus patients, and 17 postoperative hydrocephalus patients). Graph theory analysis was applied to calculate the global network measures including small-worldness, normalized clustering coefficients, normalized characteristic path length, global efficiency, and modularity. Abnormalities in regional network parameters, including nodal degree, local efficiency, clustering coefficient, and betweenness centrality, were also compared between the two patients groups (separately) and the controls using two tailed t-test at significance level of p
- Published
- 2015
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28. Characterization of cerebrospinal fluid (CSF) microbiota at the time of initial surgical intervention for children with hydrocephalus.
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Shailly Pandey, Kathryn B Whitlock, Matthew R Test, Paul Hodor, Christopher E Pope, David D Limbrick, Patrick J McDonald, Jason S Hauptman, Lucas R Hoffman, Tamara D Simon, and Cerebrospinal FLuId MicroBiota in Shunts (CLIMB) Study Group
- Subjects
Medicine ,Science - Abstract
ObjectiveTo characterize the microbiota of the cerebrospinal fluid (CSF) from children with hydrocephalus at the time of initial surgical intervention.Study designCSF was obtained at initial surgical intervention. One aliquot was stored in skim milk-tryptone-glucose-glycerol (STGG) medium and the second was unprocessed; both were then stored at -70°C. Bacterial growth for CSF samples stored in STGG were subsequently characterized using aerobic and anaerobic culture on blood agar and MALDI-TOF sequencing. All unprocessed CSF samples underwent 16S quantitative polymerase chain reaction (qPCR) sequencing, and a subset underwent standard clinical microbiological culture. CSF with culture growth (either after storage in STGG or standard clinical) were further analyzed using whole-genome amplification sequencing (WGAS).Results11/66 (17%) samples stored in STGG and 1/36 (3%) that underwent standard clinical microbiological culture demonstrated bacterial growth. Of the organisms present, 8 were common skin flora and 4 were potential pathogens; only 1 was also qPCR positive. WGAS findings and STGG culture findings were concordant for only 1 sample, identifying Staphylococcus epidermidis. No significant difference in time to second surgical intervention was observed between the STGG culture-positive and negative groups.Conclusion(s)Using high sensitivity methods, we detected the presence of bacteria in a subset of CSF samples at the time of first surgery. Therefore, the true presence of bacteria in CSF of children with hydrocephalus cannot be ruled out, though our findings may suggest these bacteria are contaminants or false positives of the detection methods. Regardless of origin, the detection of microbiota in the CSF of these children may not have any clinical significance.
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- 2023
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29. Cerebrospinal fluid NCAM-1 concentration is associated with neurodevelopmental outcome in post-hemorrhagic hydrocephalus of prematurity.
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David D Limbrick, Diego M Morales, Chevis N Shannon, John C Wellons, Abhaya V Kulkarni, Jessica S Alvey, Ron W Reeder, Volker Freimann, Richard Holubkov, Jay K Riva-Cambrin, William E Whitehead, Curtis J Rozzelle, Mandeep Tamber, W Jerry Oakes, James M Drake, Ian F Pollack, Robert P Naftel, Terrie E Inder, John R Kestle, and Hydrocephalus Clinical Research Network
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Medicine ,Science - Abstract
ObjectiveEfforts directed at mitigating neurological disability in preterm infants with intraventricular hemorrhage (IVH) and post hemorrhagic hydrocephalus (PHH) are limited by a dearth of quantifiable metrics capable of predicting long-term outcome. The objective of this study was to examine the relationships between candidate cerebrospinal fluid (CSF) biomarkers of PHH and neurodevelopmental outcomes in infants undergoing neurosurgical treatment for PHH.Study designPreterm infants with PHH were enrolled across the Hydrocephalus Clinical Research Network. CSF samples were collected at the time of temporizing neurosurgical procedure (n = 98). Amyloid precursor protein (APP), L1CAM, NCAM-1, and total protein (TP) were compared in PHH versus control CSF. Fifty-four of these PHH subjects underwent Bayley Scales of Infant Development-III (Bayley-III) testing at 15-30 months corrected age. Controlling for false discovery rate (FDR) and adjusting for post-menstrual age (PMA) and IVH grade, Pearson's partial correlation coefficients were used to examine relationships between CSF proteins and Bayley-III composite cognitive, language, and motor scores.ResultsCSF APP, L1CAM, NCAM-1, and TP were elevated in PHH over control at temporizing surgery. CSF NCAM-1 was associated with Bayley-III motor score (R = -0.422, p = 0.007, FDR Q = 0.089), with modest relationships noted with cognition (R = -0.335, p = 0.030, FDR Q = 0.182) and language (R = -0.314, p = 0.048, FDR Q = 0.194) scores. No relationships were observed between CSF APP, L1CAM, or TP and Bayley-III scores. FOHR at the time of temporization did not correlate with Bayley-III scores, though trends were observed with Bayley-III motor (p = 0.0647 and R = -0.2912) and cognitive scores (p = 0.0506 and R = -0.2966).ConclusionCSF NCAM-1 was associated with neurodevelopment in this multi-institutional PHH cohort. This is the first report relating a specific CSF protein, NCAM-1, to neurodevelopment in PHH. Future work will further investigate a possible role for NCAM-1 as a biomarker of PHH-associated neurological disability.
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- 2021
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30. Cerebrospinal fluid biomarkers of infantile congenital hydrocephalus.
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David D Limbrick, Brandon Baksh, Clinton D Morgan, Gakwaya Habiyaremye, James P McAllister, Terrie E Inder, Deanna Mercer, David M Holtzman, Jennifer Strahle, Michael J Wallendorf, and Diego M Morales
- Subjects
Medicine ,Science - Abstract
INTRODUCTION:Hydrocephalus is a complex neurological disorder with a pervasive impact on the central nervous system. Previous work has demonstrated derangements in the biochemical profile of cerebrospinal fluid (CSF) in hydrocephalus, particularly in infants and children, in whom neurodevelopment is progressing in parallel with concomitant neurological injury. The objective of this study was to examine the CSF of children with congenital hydrocephalus (CHC) to gain insight into the pathophysiology of hydrocephalus and identify candidate biomarkers of CHC with potential diagnostic and therapeutic value. METHODS:CSF levels of amyloid precursor protein (APP) and derivative isoforms (sAPPα, sAPPβ, Aβ42), tau, phosphorylated tau (pTau), L1CAM, NCAM-1, aquaporin 4 (AQP4), and total protein (TP) were measured by ELISA in 20 children with CHC. Two comparative groups were included: age-matched controls and children with other neurological diseases. Demographic parameters, ventricular frontal-occipital horn ratio, associated brain malformations, genetic alterations, and surgical treatments were recorded. Logistic regression analysis and receiver operating characteristic curves were used to examine the association of each CSF protein with CHC. RESULTS:CSF levels of APP, sAPPα, sAPPβ, Aβ42, tau, pTau, L1CAM, and NCAM-1 but not AQP4 or TP were increased in untreated CHC. CSF TP and normalized L1CAM levels were associated with FOR in CHC subjects, while normalized CSF tau levels were associated with FOR in control subjects. Predictive ability for CHC was strongest for sAPPα, especially in subjects ≤12 months of age (p
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- 2017
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31. Cerebrospinal fluid levels of amyloid precursor protein are associated with ventricular size in post-hemorrhagic hydrocephalus of prematurity.
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Diego M Morales, Richard Holubkov, Terri E Inder, Haejun C Ahn, Deanna Mercer, Rakesh Rao, James P McAllister, David M Holtzman, and David D Limbrick
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Medicine ,Science - Abstract
Neurological outcomes of preterm infants with post-hemorrhagic hydrocephalus (PHH) remain among the worst in infancy, yet there remain few instruments to inform the treatment of PHH. We previously observed PHH-associated elevations in cerebrospinal fluid (CSF) amyloid precursor protein (APP), neural cell adhesion molecule-L1 (L1CAM), neural cell adhesion molecule-1 (NCAM-1), and other protein mediators of neurodevelopment.The objective of this study was to examine the association of CSF APP, L1CAM, and NCAM-1 with ventricular size as an early step toward developing CSF markers of PHH.CSF levels of APP, L1CAM, NCAM-1, and total protein (TP) were measured in 12 preterm infants undergoing PHH treatment. Ventricular size was determined using cranial ultrasounds. The relationships between CSF APP, L1CAM, and NCAM-1, occipitofrontal circumference (OFC), volume of CSF removed, and ventricular size were examined using correlation and regression analyses.CSF levels of APP, L1CAM, and NCAM-1 but not TP paralleled treatment-related changes in ventricular size. CSF APP demonstrated the strongest association with ventricular size, estimated by frontal-occipital horn ratio (FOR) (Pearson R = 0.76, p = 0.004), followed by NCAM-1 (R = 0.66, p = 0.02) and L1CAM (R = 0.57,p = 0.055). TP was not correlated with FOR (R = 0.02, p = 0.95).Herein, we report the novel observation that CSF APP shows a robust association with ventricular size in preterm infants treated for PHH. The results from this study suggest that CSF APP and related proteins at once hold promise as biomarkers of PHH and provide insight into the neurological consequences of PHH in the preterm infant.
- Published
- 2015
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