Publications by authors named "Michelle Felicella"

Minimally invasive neural interfaces can be used to diagnose, manage and treat many disorders, with reduced risks of surgical complications. However, endovascular probes lack access to key cortical, subcortical and spinal targets, and are not typically explantable after endothelialization. Here we report the development and testing, in sheep, of endocisternal neural interfaces that approach brain and spinal cord targets through inner and outer spaces filled with cerebrospinal fluid.

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Primary central nervous system (CNS) diffuse large B-cell lymphoma with MYC and BCL2 rearrangements is a very rare lymphoma subtype. Deep brain stimulation is an effective minimally invasive therapeutic option for the treatment of refractory movement disorders, as well as some psychiatric disorders and chronic pain syndromes. Herein, we report a case of CNS lymphoma, which developed around an electrode of a deep brain stimulation (DBS) device.

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Chronic intestinal pseudo-obstruction (CIPO) is a rare, severe, and often debilitating condition that can result in significant morbidity and mortality amongst the pediatric population. Eosinophilic myenteric ganglionitis (EMG) is a rare inflammatory neuropathy of the myenteric plexus with characteristic eosinophilic infiltration with and without hypogangliosis. The disorder has been previously documented as a cause of CIPO.

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Proteins are densely packed in cells and tissues, where they form complex nanostructures. Expansion microscopy (ExM) variants have been used to separate proteins from each other in preserved biospecimens, improving antibody access to epitopes. Here, we present an ExM variant, decrowding expansion pathology (dExPath), that can expand proteins away from each other in human brain pathology specimens, including formalin-fixed paraffin-embedded (FFPE) clinical specimens.

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Article Synopsis
  • Astroblastoma is a rare brain tumor mainly affecting older children, typically found in the frontoparietal regions of the brain.
  • A 32-year-old woman experienced a recurrence of her astroblastoma 21 years after it was initially removed and treated with radiation, now presenting with seizures and imaging showing significant tumor growth.
  • The surgical removal utilized a technique called 5-aminolevulinic acid (5-ALA), which helped in the resection process, and genetic testing of the tumor identified specific fusion transcripts linked to its development.
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  • The study focuses on how exosomes from Alzheimer's disease (AD) patients contribute to problems with the blood-brain barrier (BBB), particularly affecting the integrity of adherens junction proteins in brain microvascular endothelial cells (BMECs).
  • Researchers isolated exosomes from the blood of AD patients and normal controls to investigate their effects, finding that AD exosomes reduced levels of VE-cadherin (a key protein for cell junctions) and weakened BBB integrity.
  • Results showed that the damaging effects of AD exosomes on VE-cadherin were linked to their RNA content, and AD brains exhibited lower VE-cadherin levels compared to healthy controls, emphasizing the role of exosomal RNA
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X-linked adrenoleukodystrophy is a severe demyelinating neurodegenerative disease mainly affecting males. The severe cerebral adrenoleukodystrophy (cALD) phenotype has a poor prognosis and underlying mechanism of onset and progression of neuropathology remains poorly understood. In this study we aim to integrate metabolomic and microRNA (miRNA) datasets to identify variances associated with cALD.

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Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is a recently identified diagnosis that can cause a variety of severe symptoms, including ataxia, dysarthria, diplopia, paraparesis, and vertigo. These symptoms rarely present in isolation but often accompany one another in various combinations. Magnetic Resonance Imaging (MRI) of the brain is critical for making the diagnosis and typically reveals scattered enhancement within the pons and adjacent structures.

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The ongoing epidemic caused by the coronavirus SARS-CoV-2 is characterized by a variety of pathologic processes within the syndrome of COVID-19. Usually beginning as an upper respiratory infection with potential progression to a pneumonitis, many cases of COVID-19 that show minimal signs or symptoms initially may develop adverse systemic sequelae later, such as widespread thrombo-embolic phenomena, systemic inflammatory disorders (especially in children), or vasculitis. Here, we present a patient who suffered a sudden cardiac death following persistent SARS-CoV-2 viral positivity for four-and-one-half months after a mild clinical viral course.

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Background: Blood-brain barrier (BBB) breakdown is a component of the progression and pathology of Alzheimer's disease (AD). BBB dysfunction is primarily caused by reduced or disorganized tight junction or adherens junction proteins of brain microvascular endothelial cell (BMEC). While there is growing evidence of tight junction disruption in BMECs in AD, the functional role of adherens junctions during BBB dysfunction in AD remains unknown.

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is an underrecognized cause of meningitis, especially in nonendemic regions. This report details disease progression from admission to autopsy in an otherwise healthy 40-year-old male in Texas. It brings awareness to an often unsuspected organism that can cause severe infection requiring early recognition and treatment in immunocompetent individuals.

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Implantable bioelectronic devices for the simulation of peripheral nerves could be used to treat disorders that are resistant to traditional pharmacological therapies. However, for many nerve targets, this requires invasive surgeries and the implantation of bulky devices (about a few centimetres in at least one dimension). Here we report the design and in vivo proof-of-concept testing of an endovascular wireless and battery-free millimetric implant for the stimulation of specific peripheral nerves that are difficult to reach via traditional surgeries.

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Aims: Resource-strained healthcare ecosystems often struggle with the adoption of the World Health Organization (WHO) recommendations for the classification of central nervous system (CNS) tumors. The generation of robust clinical diagnostic aids and the advancement of simple solutions to inform investment strategies in surgical neuropathology would improve patient care in these settings.

Methods: We used simple information theory calculations on a brain cancer simulation model and real-world data sets to compare contributions of clinical, histologic, immunohistochemical, and molecular information.

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Cystic trophoblastic tumor (CTT) is an uncommon trophoblastic proliferation of germ cell tumor origin, mostly reported in post-chemotherapy metastases of testicular germ cell tumors and rarely primary untreated testicular tumors. To date, we are not aware of occurrence in a non-testicular tumor. A 12-year-old boy presented with limb swelling, increased appetite, weight gain, and precocious puberty.

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Purpose: The 2017 World Health Organization classification of pituitary tumors redefined pituitary null cell adenomas (NCAs) by restricting this diagnostic category to pituitary tumors that are negative for pituitary transcription factors and adenohypophyseal hormones. The clinical behavior of this redefined entity has not been widely studied, and this is a major shortcoming of the classification. This study evaluated the imaging and clinical features of NCAs from two pituitary centers and compared them with those of gonadotroph adenomas (GAs).

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Objective: In the current neurosurgical and anatomical literature, the intracanalicular segment of the ophthalmic artery (OphA) is usually described to be within the optic nerve dural sheath (ONDS), implying direct contact between the nerve and the artery inside the optic canal. In the present study, the authors sought to clarify the exact relationship between the OphA and ONDS.

Methods: Ten cadaveric heads were subjected to endoscopic endonasal and transcranial exposures of the OphA in the optic canal (5 for each approach).

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Article Synopsis
  • This study investigates how genetic diversity in glioblastoma (GBM) affects treatment responses by analyzing DNA and RNA from GBM samples and derived models.
  • The researchers discovered that specific genetic changes, including mutations and amplifications, were primarily passed from tumors to model systems, with different inheritance patterns observed.
  • They found that extrachromosomal DNA (ecDNA) plays a significant role in increasing genetic variability in GBM, maintaining oncogenic potential throughout the disease progression, regardless of chromosomal DNA changes.
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Ependymomas are a subgroup of ependymal glia-derived neoplasms that affect children as well as adults. Arising within any CNS compartment, symptoms at presentation can range from acute onset due to increased intracranial pressure to insidious myelopathy. The overall survival (OS) outcomes in adult patients across the subgroups is heterogeneous with subependymoma having an excellent prognosis often even in the absence of any treatment, whereas supratentorial ependymomas tend to be higher grade in nature and may have an OS of 5 years despite gross total resection and adjuvant radiation.

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Background And Importance: Pilocytic astrocytoma (PA) is among the most common of the central nervous system gliomas in the pediatric population; however, it is uncommon in adults. PAs of the spinal cord in adults are even rarer, with only a few cases found in the literature. We report here the first case in the literature of multifocal intradural extramedullary spinal cord PAs in an adult.

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X-linked adrenoleukodystrophy (X-ALD) is a progressive neurometabolic disease caused by mutations/deletions in the Abcd1 gene. Similar mutations/deletions in the Abcd1 gene often result in diagonally opposing phenotypes of mild adrenomyeloneuropathy and severe neuroinflammatory cerebral adrenoleukodystrophy (ALD), which suggests involvement of downstream modifier genes. We recently documented the first evidence of loss of AMP-activated protein kinase α1 (AMPKα1) in ALD patient-derived cells.

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Blast phase in chronic myelogenous leukemia (CML) has rarely been reported to involve extramedullary sites like skin, lymph nodes, and central nervous system. Clinical history, characteristic hematologic findings (elevated leukocyte counts, myelocytic predominance, and basophilia), and Philadelphia chromosome are of high diagnostic significance especially in isolated extramedullary presentations. We describe a unique case of CML relapse with blast phase involving the eye.

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Pediatric glioblastomas (GBM) are highly aggressive and lethal tumors. Recent sequencing studies have shown that ~30 % of pediatric GBM and ~80 % of diffuse intrinsic pontine gliomas show K27M mutations in the H3F3A gene, a variant encoding histone H3.3.

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Trimethylation of histone 3 lysine 9 (H3K9me3) is a marker of repressed transcription. Cells transfected with mutant isocitrate dehydrogenase (IDH) show increased methylation of histone lysine residues, including H3K9me3, because of inhibition of histone demethylases by 2-hydroxyglutarate. Here, we evaluated H3K9me3 and its association with IDH mutations in 284 gliomas.

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IgG4-related disease (IgG4-RD) is a recently recognized fibro-inflammatory condition which often shows a dramatic response to steroid therapy. IgG4-RD can present either as a single lesion or as a systemic multi-organ disorder. Common histological findings include a dense lymphoplasmacytic infiltrate rich in IgG4-positive plasma cells, storiform fibrosis, and phlebitis.

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The distinction of multifocal versus multicentric gliomas can conceivably have important therapeutic implications. We present a 27-year-old man with two radiologically distinct non-enhancing infiltrative masses in the anterior frontal lobe and the posterior temporoparietal region. No intervening disease was evident on MRI modalities; the lesions were stable over a period of many months.

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