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Diabetic neuropathy is a debilitating disorder characterized by spontaneous and mechanical allodynia. The role of skin mechanoreceptors in the development of mechanical allodynia is unclear. We discovered that mice with diabetic neuropathy had decreased sirtuin 1 (SIRT1) deacetylase activity in foot skin, leading to reduced expression of brain-derived neurotrophic factor (BDNF) and subsequent loss of innervation in Meissner corpuscles, a mechanoreceptor expressing the BDNF receptor TrkB. When SIRT1 was depleted from skin, the mechanical allodynia worsened in diabetic neuropathy mice, likely due to retrograde degeneration of the Meissner-corpuscle innervating Aβ axons and aberrant formation of Meissner corpuscles which may have increased the mechanosensitivity. The same phenomenon was also noted in skin-keratinocyte specific BDNF knockout mice. Furthermore, overexpression of SIRT1 in skin induced Meissner corpuscle reinnervation and regeneration, resulting in significant improvement of diabetic mechanical allodynia. Overall, the findings suggested that skin-derived SIRT1 and BDNF function in the same pathway in skin sensory apparatus regeneration and highlighted the potential of developing topical SIRT1-activating compounds as a novel treatment for diabetic mechanical allodynia. [ABSTRACT FROM AUTHOR]

Objective: The detection of neoplastic cells in cerebral spinal fluid (CSF) is pivotal for the management of patients with central nervous system (CNS) tumours. This article delves into the CSF cytological characteristics of common CNS neoplasms, aligning with the 2021 World Health Organization (WHO) classification of CNS tumours. Methods: A retrospective review of CSF specimens positive for primary CNS neoplasms was performed at three tertiary medical centres. Only cases that had histopathologic confirmation and/or molecular workup were included. Results: Common primary CNS neoplasms seen in CSF cytology specimens include medulloblastoma, (non‐WNT/non‐SHH as well as SHH‐activated and TP53 mutant), pineoblastoma, atypical teratoid/rhabdoid tumour (AT/RT), IDH‐wildtype glioblastoma, and primary diffuse large B‐cell lymphoma of the CNS. Ependymomas and germinomas can also have CSF involvement but are less common. Although the typical histologic architecture of these tumours may not be preserved in the CSF, unique cytomorphologic features such as nuclear moulding, nuclear pleomorphism, rhabdoid cells, prominent nucleoli and rosette formation can still be appreciated. Conclusion: Adopting the updated terminology and correlating cytologic observations with molecular findings will streamline the diagnostic process, reducing the complexities and ambiguities pathologists often encounter when analysing CSF specimens for potential primary CNS neoplasms. [ABSTRACT FROM AUTHOR]

The phosphate modification of drugs is a common chemical strategy to increase solubility and allow for parenteral administration. Unfortunately, phosphate modifications often elicit treatment- or dose-limiting pruritus through an unknown mechanism. Using unbiased high-throughput drug screens, we identified the Mas-related G protein–coupled receptor X4 (MRGPRX4), a primate-specific, sensory neuron receptor previously implicated in itch, as a potential target for phosphate-modified compounds. Using both Gq-mediated calcium mobilization and G protein–independent GPCR assays, we found that phosphate-modified compounds potently activate MRGPRX4. Furthermore, a humanized mouse model expressing MRGPRX4 in sensory neurons exhibited robust phosphomonoester prodrug–evoked itch. To characterize and confirm this interaction, we further determined the structure of MRGPRX4 in complex with a phosphate-modified drug through single-particle cryo–electron microscopy (cryo-EM) and identified critical amino acid residues responsible for the binding of the phosphate group. Together, these findings explain how phosphorylated drugs can elicit treatment-limiting itch and identify MRGPRX4 as a potential therapeutic target to suppress itch and to guide future drug design. Editor's summary: Pruritus is a side effect of phospho-drugs, but the underlying mechanisms are unclear. Chien et al. screened a drug library for agonists of the human Mas-related G protein–coupled receptor X4 (MRGPRX4) linked to itch and showed that many of the identified drugs had a phosphate group. Because mice do not express MRGPRX4, the authors created a transgenic mouse expressing the human receptor in sensory neurons. Phospho-drugs elicited itch responses in transgenic but not wild-type mice. Cryo–electron microscopy of MRGPRX4 with fospropofol, a prodrug of the sedative propofol, identified direct receptor–phosphate group interactions. These results suggest a mechanism for phospho-drug–induced itch. —Daniela Neuhofer [ABSTRACT FROM AUTHOR]

Olfactory dysfunction is one of the most common symptoms of COVID‐19. In the first 2 years of the pandemic, it was frequently reported, although its incidence has significantly decreased with the emergence of the Omicron variant, which has since become the dominant viral strain. Nevertheless, many patients continue to suffer from persistent dysosmia and dysgeusia, making COVID‐19‐associated olfactory dysfunction an ongoing health concern. The proposed pathogenic mechanisms of COVID‐19‐associated olfactory dysfunction are complex and likely multifactorial. While evidence suggests that infection of sustentacular cells and associated mucosal inflammation may be the culprit of acute, transient smell loss, alterations in other components of the olfactory system (e.g., olfactory receptor neuron dysfunction, olfactory bulb injury and alterations in the olfactory cortex) may lead to persistent, long‐term olfactory dysfunction. This review aims to provide a comprehensive summary of the epidemiology, clinical manifestations and current understanding of the pathogenic mechanisms of COVID‐19‐associated olfactory dysfunction. [ABSTRACT FROM AUTHOR]

This research models and forecasts bounded ordinal time series data that can appear in various contexts, such as air quality index (AQI) levels, economic situations, and credit ratings. This class of time series data is characterized by being bounded and exhibiting a concentration of large probabilities on a few categories, such as states 0 and 1. We propose using Bayesian methods for modeling and forecasting in zero-one-inflated bounded Poisson autoregressive (ZOBPAR) models, which are specifically designed to capture the dynamic changes in such ordinal time series data. We innovatively extend models to incorporate exogenous variables, marking a new direction in Bayesian inferences and forecasting. Simulation studies demonstrate that the proposed methods accurately estimate all unknown parameters, and the posterior means of parameter estimates are robustly close to the actual values as the sample size increases. In the empirical study we investigate three datasets of daily AQI levels from three stations in Taiwan and consider five competing models for the real examples. The results exhibit that the proposed method reasonably predicts the AQI levels in the testing period, especially for the Miaoli station. [ABSTRACT FROM AUTHOR]

Objectives: Central nervous system involvement is present in 70% of patients with hemophagocytic lymphohistiocytosis (CNS-HLH). CNS-HLH is defined by neurologic deficits, neuroimaging abnormalities, or positive cerebrospinal fluid (CSF) findings. The CSF cytomorphologic spectrum of CNS-HLH, however, has not been well investigated.Methods: A retrospective review was performed on 64 CSF specimens from pediatric and adult patients with HLH. Ten patients had clinicoradiologic evidence of CNS involvement.Results: We identified five CSF cytomorphologic patterns: (1) hemophagocytosis, (2) vacuolated macrophages without evidence of hemophagocytosis, (3) monocytes and/or nonvacuolated macrophages, (4) acellular specimens, and (5) bloody specimens. Patterns 1 and 2 were common in CNS-HLH and rare in patients without CNS involvement. The CSF cytomorphologic patterns did not correlate well with WBC counts or protein concentration.Conclusions: Our study offers a comprehensive view of the cytomorphologic features seen in CSF specimens from patients with HLH. [ABSTRACT FROM AUTHOR]

Invasive aspergillosis (IA) is an important opportunistic infection among patients with liver disease and liver transplants. Diagnosis of IA may be challenging, especially among patients with central nervous system infection. Herein, we demonstrate the utility of next‐generation sequencing of microbial cell‐free DNA in the diagnosis of fungal brain abscess in a liver transplant recipient. [ABSTRACT FROM AUTHOR]

Recent characterization of spatiotemporal genomic architecture of IDH-wild-type multifocal glioblastomas (M-GBMs) suggests a clinically unobserved common-ancestor (CA) with a less aggressive phenotype, generating highly genetically divergent malignant gliomas/GBMs in distant brain regions. Using serial MRI/3D-reconstruction, whole-genome sequencing and spectral karyotyping-based single-cell phylogenetic tree building, we show two distinct types of tumor evolution in p53-mutant driven mouse models. Malignant gliomas/GBMs grow as a single mass (Type 1) and multifocal masses (Type 2), respectively, despite both exhibiting loss of Pten/chromosome 19 (chr19) and PI3K/Akt activation with sub-tetraploid/4N genomes. Analysis of early biopsied and multi-segment tumor tissues reveals no evidence of less proliferative diploid/2N lesions in Type 1 tumors. Strikingly, CA-derived relatively quiescent tumor precursors with ancestral diploid/2N genomes and normal Pten/chr19 are observed in the subventricular zone (SVZ), but are distantly segregated from multi focal Type 2 tumors. Importantly, PI3K/Akt inhibition by Rictor/mTORC2 deletion blocks distant dispersal, restricting glioma growth in the SVZ. Recent studies suggest spatial segregation of tumor initiation and manifestation in IDH-WT glioblastomas. Here, the authors use serial MRI/3D-reconstruction, whole-genome sequencing and spectral karyotyping-based single-cell phylogenetic tree building to establish this unique evolutionary mode in a murine model. [ABSTRACT FROM AUTHOR]

Children diagnosed with brain tumors have the lowest overall survival of all pediatric cancers. Recent molecular studies have resulted in the discovery of recurrent driver mutations in many pediatric brain tumors. However, despite these molecular advances, the clinical outcomes of high grade tumors, including H3K27M diffuse midline glioma (H3K27M DMG), remain poor. To address the paucity of tissue for biological studies, we have established a comprehensive protocol for the coordination and processing of donated specimens at postmortem. Since 2010, 60 postmortem pediatric brain tumor donations from 26 institutions were coordinated and collected. Patient derived xenograft models and cell cultures were successfully created (76% and 44% of attempts respectively), irrespective of postmortem processing time. Histological analysis of mid-sagittal whole brain sections revealed evidence of treatment response, immune cell infiltration and the migratory path of infiltrating H3K27M DMG cells into other midline structures and cerebral lobes. Sequencing of primary and disseminated tumors confirmed the presence of oncogenic driver mutations and their obligate partners. Our findings highlight the importance of postmortem tissue donations as an invaluable resource to accelerate research, potentially leading to improved outcomes for children with aggressive brain tumors. [ABSTRACT FROM AUTHOR]

A systematic analysis of the source duration (τ) and seismic moment (M0) for seismogenic earthquakes (MW 5.5–7.1) in the Taiwan region was completed by using a teleseismic P-wave inversion method. Irrespective of the source self-similarity, the M0–τ relationship derived in this study had a power-law form, namely M0 ∝ τ3, under the assumption that ΔσVr3 is constant following a circular fault model (Δσ: static stress drop; Vr: rupture velocity). For Taiwan's earthquakes, the derived M0–τ relationship not only provides information to predict the source duration of large earthquakes, but also probes the rupture features of seismogenic earthquakes. That is, there are different rupture patterns for earthquakes, but the product ΔσVr3 remains nearly constant. [ABSTRACT FROM AUTHOR]

Anaplastic astrocytomas are aggressive glial cancers that present poor prognosis and high recurrence. Heterozygous IDH1 R132H mutations are common in adolescent and young adult anaplastic astrocytomas. In a majority of cases, the IDH1 R132H mutation is unique to the tumor, although rare cases of anaplastic astrocytoma have been described in patients with mosaic IDH1 mutations (Ollier disease or Maffucci syndrome). Here, we present two siblings with IDH1 R132H mutant high grade astrocytomas diagnosed at 14 and 26 years of age. Analysis of IDHR132H mutations in the siblings' tumors and non-neoplastic tissues, including healthy regions of the brain, cheek cells, and primary teeth indicate mosaicism of IDHR132H. Whole exome sequencing of the tumor tissue did not reveal any other common mutations between the two siblings. This study demonstrates the first example of IDH1 R132H mosaicism, acquired during early development, that provides an alternative mechanism of cancer predisposition. [ABSTRACT FROM AUTHOR]

In diabetic neuropathy, there is activation of axonal and sensory neuronal degeneration pathways leading to distal axonopathy. The nicotinamide-adenine dinucleotide (NAD+)-dependent deacetylase enzyme, Sirtuin 1 (SIRT1), can prevent activation of these pathways and promote axonal regeneration. In this study, we tested whether increased expression of SIRT1 protein in sensory neurons prevents and reverses experimental diabetic neuropathy induced by a high fat diet (HFD). We generated a transgenic mouse that is inducible and overexpresses SIRT1 protein in neurons (nSIRT1OE Tg). Higher levels of SIRT1 protein were localized to cortical and hippocampal neuronal nuclei in the brain and in nuclei and cytoplasm of small to medium sized neurons in dorsal root ganglia. Wild-type and nSIRT1OE Tg mice were fed with either control diet (6.2% fat) or a HFD (36% fat) for 2 months. HFD-fed wild-type mice developed neuropathy as determined by abnormal motor and sensory nerve conduction velocity, mechanical allodynia, and loss of intraepidermal nerve fibres. In contrast, nSIRT1OE prevented a HFD-induced neuropathy despite the animals remaining hyperglycaemic. To test if nSIRT1OE would reverse HFD-induced neuropathy, nSIRT1OE was activated after mice developed peripheral neuropathy on a HFD. Two months after nSIRT1OE, we observed reversal of neuropathy and an increase in intraepidermal nerve fibre. Cultured adult dorsal root ganglion neurons from nSIRT1OE mice, maintained at high (30 mM) total glucose, showed higher basal and maximal respiratory capacity when compared to adult dorsal root ganglion neurons from wild-type mice. In dorsal root ganglion protein extracts from nSIRT1OE mice, the NAD+-consuming enzyme PARP1 was deactivated and the major deacetylated protein was identified to be an E3 protein ligase, NEDD4-1, a protein required for axonal growth, regeneration and proteostasis in neurodegenerative diseases. Our results indicate that nSIRT1OE prevents and reverses neuropathy. Increased mitochondrial respiratory capacity and NEDD4 activation was associated with increased axonal growth driven by neuronal overexpression of SIRT1. Therapies that regulate NAD+ and thereby target sirtuins may be beneficial in human diabetic sensory polyneuropathy. [ABSTRACT FROM AUTHOR]

Background: Endocrine mucin‐producing sweat gland carcinoma (EMPSGC) is a rare, low‐grade adnexal neoplasm that most commonly involves the eyelid. Analogous to solid papillary carcinoma of the breast, it probably represents a precursor lesion to mucinous carcinoma. Here, we describe 11 cases of EMPSGC with molecular analysis. Methods: We performed a retrospective search of the Johns Hopkins Medical Institute pathology database and identified 11 cases of EMPSGC. Immunohistochemistry was performed for chromogranin, synaptophysin, neuron specific enolase, estrogen receptor (ER), epithelial membrane antigen (EMA), cytokeratin 7 (CK7), and cytokeratin 20 (CK20). Array comparative genomic hybridization (aCGH) and BRAFV600E pyrosequencing were performed on two and three cases, respectively. Results: We observed a strong female predilection (73% females, 8/11 cases) with an average age of 66 years (range, 56‐83 years). EMPSGCs were associated with adjacent benign sweat gland cysts (3/11), atypical intraductal proliferation (1/11), and mucinous carcinoma (1/11). Immunohistochemically, all tumors expressed at least one neuroendocrine marker, ER, EMA, and CK7, and were negative for CK20. aCGH demonstrated a 6p11.2 to 6q16.1 deletion (1/2 cases). All cases were negative for BRAFV600E mutation (3/3 cases). Conclusion: This series provides further histopathologic support that EMPSGC represents a multistage progression to mucinous carcinoma. Additional studies are needed to understand its molecular mechanisms. [ABSTRACT FROM AUTHOR]

Type IV sacrococcygeal teratoma with intraspinal involvement is rare and to our knowledge has not been reported previously in the literature. The authors present the case of a 2-month-old infant with a type IV sacrococcygeal teratoma diagnosed on prenatal ultrasound. Postnatal MRI revealed intraspinal extension through an enlarged sacral neuroforamina on the right side. On surgical exploration, the authors discovered a dorsal cystic tumor involving the sacral spine that extended through an enlarged S4 foramen to a large presacral component. The tumor was successfully removed to achieve a complete en bloc surgical resection. The authors review the epidemiology, pathophysiology, and treatment of sacrococcygeal teratomas with intraspinal extension. [ABSTRACT FROM AUTHOR]

Objectives: There is a critical need to develop effective treatments for diabetic neuropathy. This study determined if a selective mGluR2/3 receptor agonist prevented or treated experimental diabetic peripheral neuropathy (DPN) through glutamate recycling and improved mitochondrial function. Methods: Adult male streptozotocin treated Sprague-Dawley rats with features of type 1 diabetes mellitus (T1DM) or Low Capacity Running (LCR) rats with insulin resistance or glucose intolerance were treated with 3 or 10 mg/kg/day LY379268. Neuropathy end points included mechanical allodynia, nerve conduction velocities (NCV), and intraepidermal nerve fiber density (IENFD). Markers of oxidative stress, antioxidant response, glutamate recycling pathways, and mitochondrial oxidative phosphorylation (OXPHOS) associated proteins were measured in dorsal root ganglia (DRG). Results: In diabetic rats, NCV and IENFD were decreased. Diabetic rats treated with an mGluR2/3 agonist did not develop neuropathy despite remaining diabetic. Diabetic DRG showed increased levels of oxidized proteins, decreased levels of glutathione, decreased levels of mitochondrial DNA (mtDNA) and OXPHOS proteins. In addition, there was a 20-fold increase in levels of glial fibrillary acidic protein (GFAP) and the levels of glutamine synthetase and glutamate transporter proteins were decreased. When treated with a specific mGluR2/3 agonist, levels of glutathione, GFAP and oxidized proteins were normalized and levels of superoxide dismutase 2 (SOD2), SIRT1, PGC-1a, TFAM, glutamate transporter proteins, and glutamine synthetase were increased in DRG neurons. Interpretation: Activation of glutamate recycling pathways protects diabetic DRG and this is associated with activation of the SIRT1-PGC-1_-TFAM axis and preservation of mitochondrial OXPHOS function. [ABSTRACT FROM AUTHOR]

To characterize the mechanism of Zika virus (ZIKV)-associated microcephaly, we performed immunolabeling on brain tissue from a 20-week fetus with intrauterine ZIKV infection. Although ZIKV demonstrated a wide range of neuronal and non-neuronal tropism, the infection rate was highest in intermediate progenitor cells and immature neurons. Apoptosis was observed in both infected and uninfected bystander cortical neurons, suggesting a role for paracrine factors in induction of neuronal apoptosis. Our results highlight differential neuronal susceptibility and neuronal apoptosis as potential mechanisms in the development of ZIKV-associated microcephaly, and may provide insights into the design and best timing of future therapy. Ann Neurol 2017;82:121-127. [ABSTRACT FROM AUTHOR]

Purpose: Conflicting challenges abound in the management of the newborn with intractable epilepsy related to hemimegalencephaly. Early hemispherectomy to stop seizures and prevent deleterious consequences to future neurocognitive development must be weighed against the technical and anesthetic challenges of performing major hemispheric surgery in the neonate. Methods: We hereby present our experience with two neonates with hemimegalencephaly and intractable seizures who were managed using a strategy of initial minimally invasive embolization of the cerebral blood supply to the involved hemisphere. Results: Immediate significant seizure control was achieved after embolization of the cerebral blood supply to the involved hemisphere followed by delayed ipsilateral hemispheric resection at a later optimal age. Conclusion: The considerations and challenges encountered in the course of the management of these patients are discussed, and a literature review is presented. [ABSTRACT FROM AUTHOR]

Alexander disease is a leukodystrophy caused by dominant missense mutations in the gene encoding the glial fibrillary acidic protein. Individuals with this disorder often present with a typical neuroradiologic pattern including white matter abnormalities with brainstem involvement, selective contrast enhancement, and structural changes to the basal ganglia/thalamus. In rare cases, focal lesions have been seen and cause concern for primary malignancies. Here the authors present an infant initially diagnosed with a chiasmatic astrocytoma that was later identified as having glial fibrillary acidic protein mutation-confirmed Alexander disease. Pathologic and radiologic considerations that were helpful in arriving at the correct diagnosis are discussed. [ABSTRACT FROM AUTHOR]

Objective To demonstrate an association between magnetic resonance imaging ( MRI) findings and pathologic characteristics in children who had surgery for medically refractory epilepsy due to focal cortical dysplasia ( FCD). Methods We retrospectively studied 110 children who had epilepsy surgery. Twenty-seven patients with FCD were included. Thirteen had temporal lobe epilepsy ( TLE) and 14 had extra-temporal lobe epilepsy ( ETLE). Three patients had associated mesial temporal sclerosis. Preoperative 3T MRIs interleaved with nine controls were blindly re-reviewed and categorized according to signal alteration. Pathologic specimens were classified according to the 2011 International League Against Epilepsy ( ILAE) classification and compared to MRI studies. Results Rates of pathology subtypes differed between TLE and ETLE (χ2(3) = 8.57, p = 0.04). FCD type I was more frequent in TLE, whereas FCD type II was more frequent in ETLE. In the TLE group, nine patients had temporal tip abnormalities. They all exhibited gray-white matter blurring with decreased myelination and white matter hyperintense signal. Blurring involved the whole temporal tip, not just the area of dysplasia. These patients were less likely to demonstrate cortical thickening compared to those without temporal tip findings (χ2(1) = 9.55, p = 0.002). Three of them had FCD Ib, three had FCD IIa, two had FCD IIIa, and one had FCD IIb; MRI features could not entirely distinguish between FCD subtypes. TLE patients showed more pronounced findings than ETLE on MRI (χ2(1) = 11.95, p = 0.003, odds ratio [ OR] 18.00). In all cases of FCD, isolated blurring was more likely to be associated with FCD II, whereas blurring with decreased myelination was seen with FCD I (χ2(6) = 13.07, p = 0.042). Significance Our study described associations between MRI characteristics and pathology in children with FCD and offered a detailed analysis of temporal lobe tip abnormalities and FCD subtypes in children with TLE. These findings may contribute to the presurgical evaluation of patients with refractory epilepsy. [ABSTRACT FROM AUTHOR]

Purpose: Seizure freedom following resection of focal cortical dysplasia (FCD) correlates with complete resection of the dysplastic cortical tissue. However, difficulty with intraoperative identification of the lesion may limit the ability to achieve the surgical objective of complete extirpation of these lesions. Intraoperative magnetic resonance imaging (iMRI) may aid in FCD resections. The objective of this study is to compare rates of postoperative seizure freedom, completeness of resection, and need for reoperation in patients undergoing iMRI-assisted FCD resection versus conventional surgical techniques. Methods: We retrospectively reviewed the medical records of pediatric subjects who underwent surgical resection of FCD at Children's National Medical Center between March 2005 and April 2015. Results: At the time of the last postoperative follow-up, 11 of the 12 patients (92 %) in the iMRI resection group were seizure free (Engel Class I), compared to 14 of the 42 patients (33 %) in the control resection group ( p = 0.0005). All 12 of the iMRI patients (100 %) achieved complete resection, compared to 24 of 42 patients (57 %) in the control group ( p = 0.01). One (8 %) patient from the iMRI-assisted resection group has required reoperation, compared to 17 (40 %) patients in the control resection group. Conclusion: Our results suggest that the utilization of iMRI during surgery for resection of FCD results in improved postoperative seizure freedom, completeness of lesion resection, and reduction in the need for reoperation. [ABSTRACT FROM AUTHOR]

Among brain tumors, the BRAF mutation is frequently associated with pleomorphic xanthoastrocytomas (PXAs) and gangliogliomas (GGs). This oncogenic mutation is also detected in ~5 % of other pediatric low-grade gliomas (LGGs) including pilocytic astrocytomas (PAs) and diffuse astrocytomas. In the current multi-institutional study of 56 non-PXA/non-GG diencephalic pediatric LGGs, the BRAF mutation rate is 36 %. V600-mutant tumors demonstrate a predilection for infants and young children (

Orbital meningiomas can be classified as primary optic nerve sheath (ON) meningiomas, primary intraorbital ectopic (Ob) meningiomas and spheno-orbital (Sph-Ob) meningiomas based on anatomic site. Single-nucleotide polymorphism (SNP)-based array analysis with the Illumina 300K platform was performed on formalin-fixed, paraffin-embedded tissue from 19 orbital meningiomas (5 ON, 4 Ob and 10 Sph-Ob meningiomas). Tumors were World Health Organization (WHO) grade I except for two grade II meningiomas, and one was NF2-associated. We found genomic alterations in 68% (13 of 19) of orbital meningiomas. Sph-Ob tumors frequently exhibited monosomy 22/22q loss (70%; 7/10) and deletion of chromosome 1p, 6q and 19p (50% each; 5/10). Among genetic alterations, loss of chromosome 1p and 6q were more frequent in clinically progressive tumors. Chromosome 22q loss also was detected in the majority of Ob meningiomas (75%; 3/4) but was infrequent in ON meningiomas (20%; 1/5). In general, Ob tumors had fewer chromosome alterations than Sph-Ob and ON tumors. Unlike Sph-Ob meningiomas, most of the Ob and ON meningiomas did not progress even after incomplete excision, although follow-up was limited in some cases. Our study suggests that ON, Ob and Sph-Ob meningiomas are three molecularly distinct entities. Our results also suggest that molecular subclassification may have prognostic implications. [ABSTRACT FROM AUTHOR]

BACKGROUND Positive cerebrospinal fluid (CSF) cytology typically indicates leptomeningeal dissemination of metastatic, secondary, or rarely, primary central nervous system (CNS) tumors. To the authors' knowledge, large-scale studies on clinicocytologic features of various primary CNS tumors in CSF are lacking. METHODS The authors performed a retrospective cytomorphologic study on 127 positive CSF specimens from 87 patients with a history of primary nonhematologic CNS tumors. Pertinent clinical, radiological, and histologic findings were reviewed. RESULTS Pediatric tumors accounted for the majority (82.6%) of the primary CNS tumors with positive CSF cytology. The most common radiological finding of neuraxial dissemination was diffuse leptomeningeal enhancement. Greater than 95% of the cases with positive CSF cytology were high-grade or malignant tumors. The most common tumor type was central primitive neuroectodermal tumors (47.2%). Overall, the frequency of initial metastasis was found to be lowest in central primitive neuroectodermal tumors and retinoblastomas (approximately one-third). They also had the longest latency (1.5-2 years) in cases without initial metastasis. The majority of metastatic tumors in CSF demonstrated distinct cytomorphology reminiscent of the histologic features of the primary tumor, such as prominent nucleoli, cell wrapping, and apoptosis in large cell/anaplastic medulloblastomas; rhabdoid morphology and cytoplasmic inclusions in atypical teratoid/rhabdoid tumors; large clusters of cells with scant cytoplasm and nuclear molding in retinoblastomas; nuclear pleomorphism and hyperchromasia in high-grade infiltrating astrocytomas; and small clusters/rosettes of epithelioid cells in ependymomas. CONCLUSIONS The results of the current study provide useful clinicoradiological information and cytomorphologic findings for both common and rare primary CNS tumors that cytopathologists might encounter on CSF examination. Cancer (Cancer Cytopathol) 2015;123:123-135. © 2014 American Cancer Society. [ABSTRACT FROM AUTHOR]

Alzheimer's disease ( AD) and Parkinson's disease ( PD) are the two most common neurodegenerative disorders, and are characterized by deposition of specific proteins in the brain. If similar abnormal protein deposits are present in the eye, it would facilitate noninvasive diagnosis and monitoring of disease progression. We therefore evaluated expression of proteins associated with AD and PD pathology in postmortem eyes and brains in a case-control study. Eyes from 11 cases of AD, 6 cases of PD or PD with dementia, and 6 age-matched controls were retrieved from the autopsy archives of The Johns Hopkins Hospital. Immunostains for β-amyloid, phospho-tau and α-synuclein and Congo red stains were performed in the same laboratory in both brains and eyes. No amyloid deposits or abnormal tau accumulations were detected in the lens, retina or other structures in the eyes of AD patients. Eyes also lacked definite Lewy bodies or Lewy neurites in either PD or AD cases. Patchy cytoplasmic α-synuclein positivity was seen in the retina of AD, PD and control cases, but did not correlate with the presence or extent of Lewy body pathology in the brain. Abnormal protein aggregations characteristic of AD and PD are thus not commonly present in the retinas or lens of affected patients when assayed using the same protocols as in the brain. This suggests that β-amyloid, phospho-tau and α-synuclein either do not deposit in the eye in a manner analogous to brain, or are present at lower levels or in different forms. [ABSTRACT FROM AUTHOR]

Electroless Ni-P/electroless Pd/immersion Au (ENEPIG) with ultra-thin Ni-P deposit serve as a potential replacement of traditional ENEPIG surface finish because of its superior electrical performance in flip chip solder joints interconnection. However, the interfacial reaction and mechanical reliability of solder joints in ENEPIG with ultra-thin Ni-P layer is not yet well evaluated. In this study, we investigated the characteristic microstructure of interfacial intermetallic compounds and high-speed impact responses of Sn-3.0Ag-0.5Cu/ENEPIG attachments with 4.8, 0.3, and 0.05 μm Ni-P deposit. ENEPIG with Ni-P layer of 0.3 μm exhibited the eutectic structure dispreading in the solder alloys and layer-type P-rich IMCs at solder/metallization interface, while there was (Cu,Ni)Sn precipitation in the solder but no P-rich IMCs layer formed in ENEPIG with 0.05 μm Ni-P layer. Slower interfacial reaction rate in ENEPIG with 0.3 μm Ni-P layer was attributed to the effect of electroless Ni-P diffusion barrier layer, which would further provide better impact resistivity than that of ENEPIG with 0.05 μm Ni-P deposit. Moreover, breach in P-rich IMCs and underneath (Cu,Ni)Sn patch were observed in ENEPIG with 0.3 μm Ni-P layer. The growth mechanism was closely related to the Ni diffusion from surface finish and element redistribution. [ABSTRACT FROM AUTHOR]