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Somatic mutations of the H3F3A and HIST1H3B genes encoding the histone H3 variants, H3.3 and H3.1, were recently identified in high-grade gliomas arising in the thalamus, pons and spinal cord of children and young adults. However, the complete range of patients and locations in which these tumors arise, as well as the morphologic spectrum and associated genetic alterations remain undefined. Here, we describe a series of 47 diffuse midline gliomas with histone H3-K27M mutation. The 25 male and 22 female patients ranged in age from 2 to 65 years (median = 14). Tumors were centered not only in the pons, thalamus, and spinal cord, but also in the third ventricle, hypothalamus, pineal region and cerebellum. Patients with pontine tumors were younger (median = 7 years) than those with thalamic (median = 24 years) or spinal (median = 25 years) tumors. A wide morphologic spectrum was encountered including gliomas with giant cells, epithelioid and rhabdoid cells, primitive neuroectodermal tumor (PNET)-like foci, neuropil-like islands, pilomyxoid features, ependymal-like areas, sarcomatous transformation, ganglionic differentiation and pleomorphic xanthoastrocytoma (PXA)-like areas. In this series, histone H3-K27M mutation was mutually exclusive with IDH1 mutation and EGFR amplification, rarely co-occurred with BRAF-V600E mutation, and was commonly associated with p53 overexpression, ATRX loss (except in pontine gliomas), and monosomy 10. [ABSTRACT FROM AUTHOR]

Objective: Identification of a particular cause of meningoencephalitis can be challenging owing to the myriad bacteria, viruses, fungi, and parasites that can produce overlapping clinical phenotypes, frequently delaying diagnosis and therapy. Metagenomic deep sequencing (MDS) approaches to infectious disease diagnostics are known for their ability to identify unusual or novel viruses and thus are well suited for investigating possible etiologies of meningoencephalitis.Methods: We present the case of a 74-year-old woman with endophthalmitis followed by meningoencephalitis. MDS of her cerebrospinal fluid (CSF) was performed to identify an infectious agent.Results: Sequences aligning to Balamuthia mandrillaris ribosomal RNA genes were identified in the CSF by MDS. Polymerase chain reaction subsequently confirmed the presence of B. mandrillaris in CSF, brain tissue, and vitreous fluid from the patient's infected eye. B. mandrillaris serology and immunohistochemistry for free-living amoebas on the brain biopsy tissue were positive.Interpretation: The diagnosis was made using MDS after the patient had been hospitalized for several weeks and subjected to costly and invasive testing. MDS is a powerful diagnostic tool with the potential for rapid and unbiased pathogen identification leading to early therapeutic targeting. [ABSTRACT FROM AUTHOR]

Strength-based assessment has achieved acceptance from educational, mental health, and social service professionals as a means to measuring emotional and behavioral strengths of children. Several standardized, norm-referenced tests have been developed to assess these strengths; however, the primary mode of assessment is via informal interviews of parents and caregivers. In many cases, these interviews lack psychometric support, including basic validity and reliability. The purpose of this study was to document the multistep process used to establish the content validity of a newly developed instrument: Behavioral and Emotional Rating Scale: Strength-Based Interview. Specifically, the results of a survey of 40 U.S. professional mental health staff and educators are described where respondents rated the importance of interview questions to the construct of strength-based assessment. The findings of the survey as well as the 18 items deemed most important are reported. Research limitations, future research, and implications for mental health and educational professionals are discussed. [ABSTRACT FROM AUTHOR]

Significance: Exogenous extracellular matrix (ECM) proteins, such as fibrinogen and the thrombin-polymerized scaffold fibrin, are used in surgical repair of severe nerve injuries to supplement ECM produced via the injury response. Monitoring the dynamic changes of fibrin during nerve regeneration may shed light on the frequent failure of grafts in the repair of long nerve gaps. Aim: We explored whether monitoring of fibrin dynamics can be carried out using nerve guidance conduits (NGCs) containing fibrin tagged with covalently bound fluorophores. Approach: Fibrinogen was conjugated to a near-infrared (NIR) fluorescent dye. NGCs consisting of silicone tubes filled with the fluorescent fibrin were used to repair a 5-mm gap injury in rat sciatic nerve (n = 6). Results: Axonal regeneration in fluorescent fibrin-filled NGCs was confirmed at 14 days after implantation. Intraoperative fluorescence imaging after implantation showed that the exogenous fibrin was embedded in the early stage regenerative tissue. The fluorescent signal temporarily highlighted a cable-like structure within the conduit and gradually degraded over two weeks. Conclusions: This study, for the first time, visualized in vivo intraneural fibrin degradation, potentially a useful prospective indicator of regeneration success, and showed that fluorescent ECM, in this case fibrin, can facilitate imaging of regeneration in peripheral nerve conduits without significantly affecting the regeneration process. [ABSTRACT FROM AUTHOR]

Processed nerve allografts are increasingly used as 'off the shelf' nerve replacements for surgically bridging nerve gaps. Benchmarking the regenerative capacity of a commercially available human-derived nerve or xenograft in a rat nerve injury model would provide a convenient platform for future studies seeking to modify the processed nerve graft. Human and rat processed nerve grafts were used to bridge a 14 mm defect in a Sprague-Dawley rat sciatic nerve. Reversed autografts served as a positive control group. Twelve weeks following surgery, the distal nerve stumps were retrograde labeled and harvested for histology and histomorphometry. The cross-sectional areas of the human- and rat-derived processed nerve grafts were similar. Neuron counts and myelinated axon counts following use of the human-derived processed xenografts were decreased compared with those obtained from both the rat-derived processed nerve allografts and the autografts; the rat-derived processed nerve allografts were statistically equivalent to autografts. Measures of nerve fiber diameter and myelination revealed inferior axon regeneration maturity in both processed nerve grafts compared with autografts. Processed xenografts showed significantly reduced regeneration compared with autografts or processed allografts indicating that cross-species immunological reactions are important considerations in this rat model. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 1085-1091, 2014. [ABSTRACT FROM AUTHOR]

Previously, combinatorial techniques were used to identify peptide sequences exhibiting high, medium, and low affinity for heparin. Bidomain peptides were synthesized containing a transglutaminase sequence for one domain and one of the heparin‐affinity sequences for the other domain. A delivery system was made consisting of bi‐domain peptides, heparin, and nerve growth factor (NGF), which binds to heparin with moderate affinity. The goal of this research was to determine whether peptide affinity for heparin and the molar ratio of peptide to heparin affected the release rate of NGF from the delivery system and the biological activity of NGF released. This study also explored whether peptide affinity modulated biological activity independent of release rate. Mathematically modeling the delivery system confirmed that release could be controlled by both peptide affinity and molar ratio of peptide to heparin. Experimentally, the rate of NGF release from the delivery system was found to be affected by peptide affinity and molar ratio. The delivery system presented biologically active NGF as assayed by embryonic chick dorsal root ganglia (DRGs) neurite extension, where extension was similar to or increased for DRGs grown in fibrin matrices containing the delivery system compared to DRGs grown with NGF in the culture media. Furthermore, by modulating the molar ratio of peptide to heparin in the delivery system, similar release rates of NGF were obtained for different affinity peptides and these conditions promoted similar levels of neurite extension, demonstrating that release rate appears to be the main mechanism controlling the biological activity of released NGF. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008 [ABSTRACT FROM AUTHOR]

Neurofibromatosis type 1, a genetic disorder caused by pathogenic germline variations in NF1, predisposes individuals to the development of tumors, including cutaneous and plexiform neurofibromas (CNs and PNs), optic gliomas, astrocytomas, juvenile myelomonocytic leukemia, high-grade gliomas and malignant peripheral nerve sheath tumors (MPNSTs), which are chemotherapy- and radiation-resistant sarcomas with poor survival. Loss of NF1 also occurs in sporadic tumors, such as glioblastoma (GBM), melanoma, breast, ovarian and lung cancers. We performed a high-throughput screen for compounds that were synthetic lethal with NF1 loss, which identified several leads, including the small molecule Y102. Treatment of cells with Y102 perturbed autophagy, mitophagy and lysosome positioning in NF1-deficient cells. A dual proteomics approach identified BLOC-one-related complex (BORC), which is required for lysosome positioning and trafficking, as a potential target of Y102. Knockdown of a BORC subunit using siRNA recapitulated the phenotypes observed with Y102 treatment. Our findings demonstrate that BORC might be a promising therapeutic target for NF1-deficient tumors. [ABSTRACT FROM AUTHOR]

The FGFR1 gene encoding fibroblast growth factor receptor 1 has emerged as a frequently altered oncogene in the pathogenesis of multiple low-grade neuroepithelial tumor (LGNET) subtypes including pilocytic astrocytoma, dysembryoplastic neuroepithelial tumor (DNT), rosette-forming glioneuronal tumor (RGNT), and extraventricular neurocytoma (EVN). These activating FGFR1 alterations in LGNET can include tandem duplication of the exons encoding the intracellular tyrosine kinase domain, in-frame gene fusions most often with TACC1 as the partner, or hotspot missense mutations within the tyrosine kinase domain (either at p.N546 or p.K656). However, the specificity of these different FGFR1 events for the various LGNET subtypes and accompanying genetic alterations are not well defined. Here we performed comprehensive genomic and epigenomic characterization on a diverse cohort of 30 LGNET with FGFR1 alterations. We identified that RGNT harbors a distinct epigenetic signature compared to other LGNET with FGFR1 alterations, and is uniquely characterized by FGFR1 kinase domain hotspot missense mutations in combination with either PIK3CA or PIK3R1 mutation, often with accompanying NF1 or PTPN11 mutation. In contrast, EVN harbors its own distinct epigenetic signature and is characterized by FGFR1-TACC1 fusion as the solitary pathogenic alteration. Additionally, DNT and pilocytic astrocytoma are characterized by either kinase domain tandem duplication or hotspot missense mutations, occasionally with accompanying NF1 or PTPN11 mutation, but lacking the accompanying PIK3CA or PIK3R1 mutation that characterizes RGNT. The glial component of LGNET with FGFR1 alterations typically has a predominantly oligodendroglial morphology, and many of the pilocytic astrocytomas with FGFR1 alterations lack the biphasic pattern, piloid processes, and Rosenthal fibers that characterize pilocytic astrocytomas with BRAF mutation or fusion. Together, this analysis improves the classification and histopathologic stratification of LGNET with FGFR1 alterations. [ABSTRACT FROM AUTHOR]

The use of acellular nerve allografts (ANAs) to reconstruct long nerve gaps (>3 cm) is associated with limited axon regeneration. To understand why ANA length might limit regeneration, we focused on identifying differences in the regenerative and vascular microenvironment that develop within ANAs based on their length. A rat sciatic nerve gap model was repaired with either short (2 cm) or long (4 cm) ANAs, and histomorphometry was used to measure myelinated axon regeneration and blood vessel morphology at various timepoints (2-, 4- and 8-weeks). Both groups demonstrated robust axonal regeneration within the proximal graft region, which continued across the mid-distal graft of short ANAs as time progressed. By 8 weeks, long ANAs had limited regeneration across the ANA and into the distal nerve (98 vs. 7583 axons in short ANAs). Interestingly, blood vessels within the mid-distal graft of long ANAs underwent morphological changes characteristic of an inflammatory pathology by 8 weeks post surgery. Gene expression analysis revealed an increased expression of pro-inflammatory cytokines within the mid-distal graft region of long vs. short ANAs, which coincided with pathological changes in blood vessels. Our data show evidence of limited axonal regeneration and the development of a pro-inflammatory environment within long ANAs. [ABSTRACT FROM AUTHOR]

Highlights from the article: ATRX expression was retained in tumor nuclei in both components, p53 staining was positive in only scattered tumor nuclei, and an IDH1-R132H stain was negative for mutant protein expression. The shared alterations of I MAP2K1 i mutation and I CDKN2A/B i homozygous deletion supports that low and high grade elements in this tumor represent morphologically distinct components of a single clonal neoplasm. Shared histopathologic features between this case and MVNT include foci of nodular growth and tumor cells with vacuolar alteration and a compatible immunophenotype. We cannot determine for certain whether the original tumor was a ganglioglioma, MVNT, mixed ganglioglioma/MVNT, or even another type of low-grade neuroepithelial neoplasm.

Insights into the molecular underpinnings of primary central nervous system tumors have radically changed the approach to tumor diagnosis and classification. Diagnostic emphasis has shifted from the morphology of a tumor under the microscope to an integrated approach based on morphologic and molecular features, including gene mutations, chromosomal copy number alterations, and gene rearrangements. In 2016, the World Health Organization provided guidelines for making an integrated diagnosis that incorporates both morphologic and molecular features in a subset of brain tumors. The integrated diagnosis now applies to infiltrating gliomas, a category that includes diffusely infiltrating astrocytoma grades II, III, and IV, and oligodendroglioma, grades II and III, thereby encompassing the most common primary intra-axial central nervous system tumors. Other neoplasms such as medulloblastoma, embryonal tumor with multilayered rosettes, certain supratentorial ependymomas, and atypical teratoid/rhabdoid tumor are also eligible for integrated diagnosis, which can sometimes be aided by characteristic immunohistochemical markers. Since 2016, advances in molecular neuro-oncology have resulted in periodic updates and clarifications to the integrated diagnostic approach. These advances reflect expanding knowledge on the molecular pathology of brain tumors, but raise a challenge in rapidly incorporating new molecular findings into diagnostic practice. This review provides a background on the molecular characteristics of primary brain tumors, emphasizing the molecular basis for classification of infiltrating gliomas, the most common entities that are eligible for an integrated diagnosis. We then discuss entities within the diffuse gliomas that do not receive an integrated diagnosis by WHO 2016 criteria, but have distinctive molecular features that are important to recognize because their clinical behavior can influence clinical management and prognosis. Particular attention is given to the histone H3 G34R/G34V mutant astrocytomas, an entity to consider when faced with an infiltrating glioma in the cerebral hemisphere of children and young adults, and to the group of histologically lower grade diffuse astrocytic gliomas with molecular features of glioblastoma, an important category of tumors to recognize due to their aggressive clinical behavior. [ABSTRACT FROM AUTHOR]

• Literature review and meta-analysis on small team and unit resilience was performed. • Focus on studies with trainings or interventions. • Evaluated across four resilience phases: prepare, absorb, recover, adapt. • Results suggest a focus on recovery, limited attention on absorption/adaptation. Resilience is increasingly recognized as a factor that improves the functioning and performance of individuals and communities; however, it is underexamined in smaller groups or teams. We performed a comprehensive literature review to examine how resilience is defined, measured and used in small teams. Additionally, we evaluated the effectiveness of trainings or interventions on teams towards increasing unit resilience and performance. Following a literature review, 74 measures across 37 articles were assessed. Study eligibility criteria include English-language publications between 1980 and 2017 that included output from a research trial or survey on military or civilian groups pertaining to their resiliency to adverse events. Resilience of units/teams was assessed across the four phases of resilience defined by NAS: prepare, absorb, recover, adapt. Our review found that while the concept of resilience is not often studied in small groups empirically, the focus of available studies is on recovery with limited attention given to absorption and adaptation. This work reveals a potential mechanism to improve team/unit performance via unit resilience training and improved unit cohesion. Training had small but significant effects on the preparation (r = 0.03, k = 5) and recover (r = 0.05, k = 6) phases of unit resilience. In order to improve resilience in small groups, training programs and other interventions must be appropriately focused on the essential phases of resilience associated with mission execution. [ABSTRACT FROM AUTHOR]

Introduction/Aims: Promoting regeneration after segmental nerve injury repair is a challenge, but improving angiogenesis could be beneficial. Macrophages facilitate regeneration after injury by promoting angiogenesis. Our aim in this study was to evaluate the feasibility and effects of transplanting exogenous macrophages to a segmental nerve injury. Methods: Bone marrow–derived cells were harvested from donor mice and differentiated to macrophages (BMDM), then suspended within fibrin hydrogels to facilitate BMDM transplantation. BMDM survival was characterized in vitro. The effect of this BMDM fibrin hydrogel construct at a nerve injury site was assessed using a mouse sciatic nerve gap injury. Mice were equally distributed to "fibrin+Mφ" (fibrin hydrogels containing culture medium and BMDM) or "fibrin" hydrogel control (fibrin hydrogels containing culture medium alone) groups. Flow cytometry (n = 3/group/endpoint) and immunohistochemical analysis (n = 5/group/endpoint) of the nerve gap region were performed at days 3, 5, and 7 after repair. Results: Incorporating macrophage colony‐stimulating factor (M‐CSF) improved BMDM survival and expansion. Transplanted BMDM survived for at least 7 days in a nerve gap (~40% retained at day 3 and ~15% retained at day 7). From transplantation, macrophage quantities within the nerve gap were elevated when comparing fibrin+Mφ with fibrin control (~25% vs. 3% at day 3 and ~14% vs. 6% at day 7). Endothelial cells increased by about fivefold within the nerve gap, and axonal extension into the nerve gap increased almost twofold for fibrin+Mφ compared with fibrin control. Discussion: BMDM suspended within fibrin hydrogels at a nerve gap do not impair regeneration. [ABSTRACT FROM AUTHOR]

Purpose To evaluate the regenerative effect of the additional suture line when using either isografts (ISOs) or acellular nerve allografts (ANAs) placed end-to-end to span a short gap in a rat model. Methods Rat sciatic nerves were transected and repaired with 2-cm nerve grafts (ISO or ANA). The grafts were 2 cm in length or a 1-cm segment was connected end-to-end to a 1-cm segment to yield a 2-cm length. At 8 weeks, extensor digitorum longus (EDL) muscle force and mass were measured. Nerves were harvested for histomorphometry. In a separate parallel study, the nerves were harvested 2 weeks following graft implantation to assess gene expression changes. Results All grafts demonstrated regeneration across the 2-cm segment(s). The additional suture line did not result in statistical differences in the number of myelinated nerve fibers that reached the distal nerve. However, when the graft types were compared, there was a significant decrease in nerve fibers in the ANA groups. The EDL muscle mass was significantly greater by using nerve ISOs compared with ANAs, regardless of an additional suture line, but there were no statistical differences noted in EDL muscle force. Gene expression analysis did not differ owing to an additional suture line. Conclusions Minimal axonal loss and no functional deficits were identified with an additional suture line in this rodent short nerve gap model. Clinical relevance Placing nerve grafts in series is a viable option for treating short nerve gaps; however, the use of autografts remains preferable over the use of ANAs. [ABSTRACT FROM AUTHOR]

Introduction/Aims: Repaired nerve injuries can fail to achieve functional recovery. Therapeutic options beyond surgery, such as systemic tacrolimus (FK506) and electrical stimulation (E‐stim), can improve recovery. We tested whether dual administration of FK506 and E‐stim enhances regeneration and recovery more than either therapeutic alone. Methods: Rats were randomized to four groups: E‐stim, FK506, FK506 + E‐stim, and repair alone. All groups underwent tibial nerve transection and repair. Two sets of animals were created to measure outcomes of early nerve regeneration using nerve histology (n = 36) and functional recovery (n = 42) (21‐ and 42‐day endpoints, respectively). Functional recovery was measured by behavioral analyses (walking track and grid walk) and, at the endpoint, muscle mass and force. Results: Dual E‐stim and FK506 administration produced histomorphometric measurements of nerve regeneration no different than either therapeutic alone. All treatments were superior to repair alone (FK506, P <.0001; E‐stim, P <.05; FK506 + E‐stim, P <.05). The E‐stim and FK506 + E‐stim groups had improved behavioral recovery compared with repair alone (at 6 weeks: E‐stim, P <.05; FK506 + E‐stim, P <.01). The FK506 group had improved recovery based on walking‐track analysis (at 6 weeks: P <.001) and muscle force and mass (P <.05). The concurrent use of both therapies ensured earlier functional recovery and decreased variability in functional outcomes compared with either therapy alone, suggesting a moderate benefit. Discussion: Dual administration of FK506 and E‐stim showed minimal additive effects to further improve regeneration or recovery compared with either therapy alone. The data suggest the combination of FK506 and E‐stim appears to combine the relative strengths of each therapeutic. [ABSTRACT FROM AUTHOR]

Glioblastoma IDH-wildtype presents with a wide histological spectrum. Some features are so distinctive that they are considered as separate histological variants or patterns for the purpose of classification. However, these usually lack defined (epi-)genetic alterations or profiles correlating with this histology. Here, we describe a molecular subtype with overlap to the unique histological pattern of glioblastoma with primitive neuronal component. Our cohort consists of 63 IDH-wildtype glioblastomas that harbor a characteristic DNA methylation profile. Median age at diagnosis was 59.5 years. Copy-number variations and genetic sequencing revealed frequent alterations in TP53, RB1 and PTEN, with fewer gains of chromosome 7 and homozygous CDKN2A/B deletions than usually described for IDH-wildtype glioblastoma. Gains of chromosome 1 were detected in more than half of the cases. A poorly differentiated phenotype with frequent absence of GFAP expression, high proliferation index and strong staining for p53 and TTF1 often caused misleading histological classification as carcinoma metastasis or primitive neuroectodermal tumor. Clinically, many patients presented with leptomeningeal dissemination and spinal metastasis. Outcome was poor with a median overall survival of only 12 months. Overall, we describe a new molecular subtype of IDH-wildtype glioblastoma with a distinct histological appearance and genetic signature. [ABSTRACT FROM AUTHOR]