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1.
Clin Infect Dis ; 78(Suppl 1): S55-S63, 2024 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-38294117

RESUMEN

BACKGROUND: Neuroinvasive infection with Francisella tularensis, the causative agent of tularemia, is rare. Establishing clinical suspicion is challenging if risk factors or clinical features classically associated with tularemia are absent. Tularemia is treatable with antibiotics; however, there are limited data to inform management of potentially fatal neuroinvasive infection. METHODS: We collected epidemiologic and clinical data on 2 recent US cases of neuroinvasive F. tularensis infection, and performed a literature review of cases of neuroinvasive F. tularensis infection published after 1950. RESULTS: One patient presented with focal neurologic deficits and brain lesions; broad-range molecular testing on resected brain tissue detected F. tularensis. The other patient presented with meningeal signs; tularemia was suspected based on animal exposure, and F. tularensis grew in cerebrospinal fluid (CSF) culture. Both patients received combination antibiotic therapy and recovered from infection. Among 16 published cases, tularemia was clinically suspected in 4 cases. CSF often displayed lymphocytic pleocytosis. Among cases with available data, CSF culture was positive in 13 of 16 cases, and F. tularensis antibodies were detected in 11 of 11 cases. Treatment typically included an aminoglycoside combined with either a tetracycline or a fluoroquinolone. Outcomes were generally favorable. CONCLUSIONS: Clinicians should consider neuroinvasive F. tularensis infection in patients with meningitis and signs suggestive of tularemia or compatible exposures, lymphocyte-predominant CSF, unrevealing standard microbiologic workup, or lack of response to empiric bacterial meningitis treatment. Molecular testing, culture, and serologic testing can reveal the diagnosis. Favorable outcomes can be achieved with directed antibiotic treatment.


Asunto(s)
Francisella tularensis , Meningitis , Tularemia , Animales , Humanos , Tularemia/diagnóstico , Tularemia/tratamiento farmacológico , Tularemia/microbiología , Antibacterianos/uso terapéutico , Aminoglicósidos/uso terapéutico
2.
Brain ; 136(Pt 2): 508-21, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23413262

RESUMEN

The ß-tropomyosin gene encodes a component of the sarcomeric thin filament. Rod-shaped dimers of tropomyosin regulate actin-myosin interactions and ß-tropomyosin mutations have been associated with nemaline myopathy, cap myopathy, Escobar syndrome and distal arthrogryposis types 1A and 2B. In this study, we expand the allelic spectrum of ß-tropomyosin-related myopathies through the identification of a novel ß-tropomyosin mutation in two clinical contexts not previously associated with ß-tropomyosin. The first clinical phenotype is core-rod myopathy, with a ß-tropomyosin mutation uncovered by whole exome sequencing in a family with autosomal dominant distal myopathy and muscle biopsy features of both minicores and nemaline rods. The second phenotype, observed in four unrelated families, is autosomal dominant trismus-pseudocamptodactyly syndrome (distal arthrogryposis type 7; previously associated exclusively with myosin heavy chain 8 mutations). In all four families, the mutation identified was a novel 3-bp in-frame deletion (c.20_22del) that results in deletion of a conserved lysine at the seventh amino acid position (p.K7del). This is the first mutation identified in the extreme N-terminus of ß-tropomyosin. To understand the potential pathogenic mechanism(s) underlying this mutation, we performed both computational analysis and in vivo modelling. Our theoretical model predicts that the mutation disrupts the N-terminus of the α-helices of dimeric ß-tropomyosin, a change predicted to alter protein-protein binding between ß-tropomyosin and other molecules and to disturb head-to-tail polymerization of ß-tropomyosin dimers. To create an in vivo model, we expressed wild-type or p.K7del ß-tropomyosin in the developing zebrafish. p.K7del ß-tropomyosin fails to localize properly within the thin filament compartment and its expression alters sarcomere length, suggesting that the mutation interferes with head-to-tail ß-tropomyosin polymerization and with overall sarcomeric structure. We describe a novel ß-tropomyosin mutation, two clinical-histopathological phenotypes not previously associated with ß-tropomyosin and pathogenic data from the first animal model of ß-tropomyosin-related myopathies.


Asunto(s)
Lisina/genética , Enfermedades Musculares/diagnóstico , Enfermedades Musculares/genética , Eliminación de Secuencia , Tropomiosina/genética , Adolescente , Adulto , Secuencia de Aminoácidos , Animales , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Enfermedades Musculares/patología , Tropomiosina/química , Adulto Joven , Pez Cebra
3.
Pain Res Manag ; 2024: 3339753, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38803624

RESUMEN

Methods: 30 male patients with primary inguinal hernias undergoing primary inguinal herniorrhaphy were prospectively recruited for ilioinguinal nerve resection and evaluation. Three samples of the resected ilioinguinal nerve (proximal, canal, and distal) were evaluated using Masson's trichrome stain to measure fascicle and total nerve cross-sectional area and detect changes in collagen. Results: The fascicle cross-sectional area in the canal segment was significantly decreased compared to the proximal control with a large effect size observed (p = 0.016, η2 = 0.16). There was no significant difference in the nerve cross-sectional area between locations, but there was a moderate to large effect size observed between locations (p = 0.165, η2 = 0.105). There was no significant difference in collagen content nor effect size observed between locations (p = 0.99, η2 = 1.503 × 10-4). Interpretation. The decrease in the fascicle cross-sectional area within the inguinal canal further suggests that there is chronic pressure applied by hernia tissue consistent with axon degeneration. Collagen content is uniformly distributed along the length of the nerve. Further studies with larger samples are needed to confirm the observed effect of nerve location on the total nerve cross-sectional area and axon loss.


Asunto(s)
Hernia Inguinal , Herniorrafia , Conducto Inguinal , Síndromes de Compresión Nerviosa , Humanos , Masculino , Hernia Inguinal/cirugía , Persona de Mediana Edad , Síndromes de Compresión Nerviosa/cirugía , Conducto Inguinal/inervación , Conducto Inguinal/patología , Conducto Inguinal/cirugía , Anciano , Adulto , Colágeno/metabolismo , Estudios Prospectivos
4.
J Physiol ; 591(12): 3049-61, 2013 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-23629510

RESUMEN

Little is known about the contraction and relaxation properties of fetal skeletal muscle, and measurements thus far have been made with non-human mammalian muscle. Data on human fetal skeletal muscle contraction are lacking, and there are no published reports on the kinetics of either fetal or adult human skeletal muscle myofibrils. Understanding the contractile properties of human fetal muscle would be valuable in understanding muscle development and a variety of muscle diseases that are associated with mutations in fetal muscle sarcomere proteins. Therefore, we characterised the contractile properties of developing human fetal skeletal muscle and compared them to adult human skeletal muscle and rabbit psoas muscle. Electron micrographs showed human fetal muscle sarcomeres are not fully formed but myofibril formation is visible. Isolated myofibril mechanical measurements revealed much lower specific force, and slower rates of isometric force development, slow phase relaxation, and fast phase relaxation in human fetal when compared to human adult skeletal muscle. The duration of slow phase relaxation was also significantly longer compared to both adult groups, but was similarly affected by elevated ADP. F-actin sliding on human fetal skeletal myosin coated surfaces in in vitro motility (IVM) assays was much slower compared with adult rabbit skeletal myosin, though the Km(app) (apparent (fitted) Michaelis-Menten constant) of F-actin speed with ATP titration suggests a greater affinity of human fetal myosin for nucleotide binding. Replacing ATP with 2 deoxy-ATP (dATP) increased F-actin speed for both groups by a similar amount. Titrations of ADP into IVM assays produced a similar inhibitory affect for both groups, suggesting ADP binding may be similar, at least under low load. Together, our results suggest slower but similar mechanisms of myosin chemomechanical transduction for human fetal muscle that may also be limited by immature myofilament structure.


Asunto(s)
Feto/fisiología , Contracción Isométrica , Músculo Esquelético/embriología , Músculo Esquelético/fisiología , Actinas/metabolismo , Adenosina Difosfato/metabolismo , Adulto , Animales , Proteínas del Citoesqueleto/metabolismo , Desarrollo Fetal , Feto/ultraestructura , Humanos , Cinética , Relajación Muscular , Músculo Esquelético/ultraestructura , Miosinas/metabolismo , Conejos , Sarcómeros/metabolismo , Sarcómeros/fisiología , Sarcómeros/ultraestructura
5.
J Neurosurg Case Lessons ; 5(21)2023 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-37218736

RESUMEN

BACKGROUND: Schizencephaly is an uncommon central nervous system malformation. Intracranial lipomas are also rare, accounting for approximately 0.1% of brain "tumors." They are believed to be derived from a persistent meninx primitiva, a neural crest-derived mesenchyme that develops into the dura and leptomeninges. OBSERVATIONS: The authors present a case of heterotopic adipose tissue and a nonshunting arterial vascular malformation arising within a schizencephalic cleft in a 22-year-old male. Imaging showed right frontal gray matter abnormality and an associated suspected arteriovenous malformation with evidence of hemorrhage. Brain magnetic resonance imaging revealed right frontal polymicrogyria lining an open-lip schizencephaly, periventricular heterotopic gray matter, fat within the schizencephalic cleft, and gradient echo hypointensity concerning for prior hemorrhage. Histological assessment demonstrated mature adipose tissue with large-bore, thick-walled, irregular arteries. Mural calcifications and subendothelial cushions suggesting nonlaminar blood flow were observed. There were no arterialized veins or direct transitions from the arteries to veins. Hemosiderin deposition was scant, and hemorrhage was not present. The final diagnosis was consistent with ectopic mature adipose tissue and arteries with meningocerebral cicatrix. LESSONS: This example of a complex maldevelopment of derivatives of the meninx primitiva in association with cortical maldevelopment highlights the unique challenges from both a radiological and histological perspective during diagnostic workup.

6.
J Neurosurg ; 139(5): 1216-1224, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37119095

RESUMEN

OBJECTIVE: Pituitary tumors (PTs) continue to present unique challenges given their proximity to the cavernous sinus, whereby invasive behavior can limit the extent of resection and surgical outcome, especially in functional tumors. The aim of this study was to elucidate patterns of cavernoinvasive behavior by PT subtype. METHODS: A total of 169 consecutive first-time surgeries for PTs were analyzed; 45% of the tumors were functional. There were 64 pituitary transcription factor-1 (PIT-1)-expressing, 62 steroidogenic factor-1 (SF-1)-expressing, 38 T-box transcription factor (TPIT)-expressing, and 5 nonstaining PTs. The gold standard for cavernous sinus invasion (CSI) was based on histopathological examination of the cavernous sinus medial wall and intraoperative exploration. RESULTS: Cavernous sinus disease was present in 33% of patients. Of the Knosp grade 3 and 4 tumors, 12 (19%) expressed PIT-1, 7 (11%) expressed SF-1, 8 (21%) expressed TPIT, and 2 (40%), were nonstaining (p = 0.36). PIT-1 tumors had a significantly higher predilection for CSI: 53% versus 24% and 18% for TPIT and SF-1 tumors, respectively (OR 6.08, 95% CI 2.86-13.55; p < 0.001). Microscopic CSI-defined as Knosp grade 0-2 tumors with confirmed invasion-was present in 44% of PIT-1 tumors compared with 7% and 13% of TPIT and SF-1 tumors, respectively (OR 11.72, 95% CI 4.35-35.50; p < 0.001). Using the transcavernous approach to excise cavernous sinus disease, surgical biochemical remission rates for patients with acromegaly, prolactinoma, and Cushing disease were 88%, 87%, and 100%, respectively. The granule density of PIT-1 tumors and corticotroph functional status did not influence CSI. CONCLUSIONS: The likelihood of CSI differed by transcription factor expression; PIT-1-expressing tumors had a higher predilection for invading the cavernous sinus, particularly microscopically, compared with the other tumor subtypes. This elucidates a unique cavernoinvasive behavior absent in cells from other lineages. Innovative surgical techniques, however, can mitigate tumor behavior and achieve robust, reproducible biochemical remission and gross-total resection rates. These findings can have considerable implications on the surgical management and study of PT biology and behavior.


Asunto(s)
Adenoma , Seno Cavernoso , Neoplasias Hipofisarias , Humanos , Neoplasias Hipofisarias/cirugía , Neoplasias Hipofisarias/patología , Adenoma/cirugía , Adenoma/patología , Seno Cavernoso/cirugía , Seno Cavernoso/patología , Procedimientos Neuroquirúrgicos/métodos , Factores de Transcripción , Resultado del Tratamiento , Estudios Retrospectivos
7.
Acta Biomater ; 164: 317-331, 2023 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-37098400

RESUMEN

Myelinated axons (nerve fibers) efficiently transmit signals throughout the brain via action potentials. Multiple methods that are sensitive to axon orientations, from microscopy to magnetic resonance imaging, aim to reconstruct the brain's structural connectome. As billions of nerve fibers traverse the brain with various possible geometries at each point, resolving fiber crossings is necessary to generate accurate structural connectivity maps. However, doing so with specificity is a challenging task because signals originating from oriented fibers can be influenced by brain (micro)structures unrelated to myelinated axons. X-ray scattering can specifically probe myelinated axons due to the periodicity of the myelin sheath, which yields distinct peaks in the scattering pattern. Here, we show that small-angle X-ray scattering (SAXS) can be used to detect myelinated, axon-specific fiber crossings. We first demonstrate the capability using strips of human corpus callosum to create artificial double- and triple-crossing fiber geometries, and we then apply the method in mouse, pig, vervet monkey, and human brains. We compare results to polarized light imaging (3D-PLI), tracer experiments, and to outputs from diffusion MRI that sometimes fails to detect crossings. Given its specificity, capability of 3-dimensional sampling and high resolution, SAXS could serve as a ground truth for validating fiber orientations derived using diffusion MRI as well as microscopy-based methods. STATEMENT OF SIGNIFICANCE: To study how the nerve fibers in our brain are interconnected, scientists need to visualize their trajectories, which often cross one another. Here, we show the unique capacity of small-angle X-ray scattering (SAXS) to study these fiber crossings without use of labeling, taking advantage of SAXS's specificity to myelin - the insulating sheath that is wrapped around nerve fibers. We use SAXS to detect double and triple crossing fibers and unveil intricate crossings in mouse, pig, vervet monkey, and human brains. This non-destructive method can uncover complex fiber trajectories and validate other less specific imaging methods (e.g., MRI or microscopy), towards accurate mapping of neuronal connectivity in the animal and human brain.


Asunto(s)
Encéfalo , Humanos , Animales , Ratones , Porcinos , Chlorocebus aethiops , Haplorrinos , Dispersión del Ángulo Pequeño , Rayos X , Difracción de Rayos X , Encéfalo/diagnóstico por imagen
8.
Clin Chem ; 58(2): 366-74, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22205691

RESUMEN

BACKGROUND: The current gold standard for diagnostic classification of many solid-tissue neoplasms is immunohistochemistry (IHC) performed on formalin-fixed, paraffin-embedded (FFPE) tissue. Although IHC is commonly used, there remain important issues related to preanalytic variability, nonstandard methods, and operator bias that may contribute to clinically significant error. To increase the quantitative accuracy and reliability of FFPE tissue-based diagnosis, we sought to develop a clinical proteomic method to characterize protein expression in pathologic tissue samples rapidly and quantitatively. METHODS: We subclassified FFPE tissue from 136 clinical pituitary adenoma samples according to hormone translation with IHC and then extracted tissue proteins and quantified pituitary hormones with multiplex bead-based immunoassays. Hormone concentrations were normalized and compared across diagnostic groups. We developed a quantitative classification scheme for pituitary adenomas on archived samples and validated it on prospectively collected clinical samples. RESULTS: The most abundant relative hormone concentrations differentiated sensitively and specifically between IHC-classified hormone-expressing adenoma types, correctly predicting IHC-positive diagnoses in 85% of cases overall, with discrepancies found only in cases of clinically nonfunctioning adenomas. Several adenomas with clinically relevant hormone-expressing phenotypes were identified with this assay yet called "null" by IHC, suggesting that multiplex immunoassays may be more sensitive than IHC for detecting clinically meaningful protein expression. CONCLUSIONS: Multiplex immunoassays performed on FFPE tissue extracts can provide diagnostically relevant information and may exceed the performance of IHC in classifying some pituitary neoplasms. This technique is simple, largely amenable to automation, and likely applicable to other diagnostic problems in molecular pathology.


Asunto(s)
Adenoma/diagnóstico , Hormonas Peptídicas/metabolismo , Neoplasias Hipofisarias/diagnóstico , Adenoma/clasificación , Adenoma/metabolismo , Fijadores , Formaldehído , Humanos , Inmunoensayo , Inmunohistoquímica , Adhesión en Parafina , Neoplasias Hipofisarias/clasificación , Neoplasias Hipofisarias/metabolismo , Estudios Prospectivos , Proteómica
9.
Front Hum Neurosci ; 16: 838692, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35911597

RESUMEN

Alzheimer's disease (AD) is a debilitating brain disorder that afflicts millions worldwide with no effective treatment. Currently, AD progression has primarily been characterized by abnormal accumulations of ß-amyloid within plaques and phosphorylated tau within neurofibrillary tangles, giving rise to neurodegeneration due to synaptic and neuronal loss. While ß-amyloid and tau deposition are required for clinical diagnosis of AD, presence of such abnormalities does not tell the complete story, and the actual mechanisms behind neurodegeneration in AD progression are still not well understood. Support for abnormal iron accumulation playing a role in AD pathogenesis includes its presence in the early stages of the disease, its interactions with ß-amyloid and tau, and the important role it plays in AD related inflammation. In this review, we present the existing evidence of pathological iron accumulation in the human AD brain, as well as discuss the imaging tools and peripheral measures available to characterize iron accumulation and dysregulation in AD, which may help in developing iron-based biomarkers or therapeutic targets for the disease.

10.
Ocul Oncol Pathol ; 8(2): 133-140, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35959159

RESUMEN

Introduction: Uveal melanoma (UM) is the most common primary intraocular malignancy in adults, and despite treatment of the primary tumor, approximately 15%-50% of patients will develop metastatic disease. Based on gene expression profiling (GEPs), UM can be categorized as Class 1A (low metastatic risk), Class 1B (intermediate metastatic risk), or Class 2 (high metastatic risk). PReferentially expressed Antigen in MElanoma (PRAME) status is an independent prognostic UM biomarker and a potential target for immunotherapy in metastatic UM. PRAME expression status can be detected in tumors using reverse-transcription polymerase chain reaction (RT-PCR). More recently, immunohistochemistry (IHC) has been developed to detect PRAME protein expression. Here, we employed both techniques to evaluate PRAME expression in 18 UM enucleations. Methods: Tumor material from the 18 UM patients who underwent enucleation was collected by fine-needle aspiration before or during enucleation and sent for GEP and PRAME analysis by RT-PCR. Histologic sections from these patients were stained with an anti-PRAME monoclonal antibody. We collected patient demographics and tumor characteristics and included this with our analysis of GEP class, PRAME status by RT-PCR, and PRAME status by IHC. PRAME IHC and RT-PCR results were compared. Results: Twelve males (12/18) and 6 females (6/18) with an average age of 60.6 years underwent enucleation for UM. TNM staging of the UM diagnosed Stage I in 2 patients (2/18), Stage II in 7 patients (7/18), Stage III in 8 patients (8/18), and Stage IV in 1 (1/18). GEP was Class 1A in 6 tumors (6/18), Class 1B in 6 tumors (6/18), and Class 2 in 6 tumors (6/18). PRAME IHC showed diffusely positive labeling of all UM cells in 2/18 enucleations; negative IHC labeling of UM cells in 9/18 enucleations; and IHC labeling of subsets of UM cells in 7/18 enucleations. Eleven of the 17 UMs tested for PRAME by both RT-PCR and IHC had consistent PRAME results. In the remaining 6/17 cases tested by both modalities, PRAME results were discordant between RT-PCR and IHC. Conclusions: We find that PRAME IHC distinguishes PRAME-positive and PRAME-negative UM tumor cells. Interestingly, IHC reveals focal PRAME expression in subsets of tumor cells consistent with tumor heterogeneity. PRAME RT-PCR and IHC provide concordant results in most of our cases. We suggest that discordance in PRAME results could arise from spatial or temporal variation in PRAME expression between tumor cells. Further studies are required to determine the prognostic implications of PRAME IHC in UM.

11.
Cureus ; 13(1): e12809, 2021 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-33628677

RESUMEN

For intracranial meningiomas that metastasize extracranially, an oligometastatic state exists that is intermediate between incurable, widely metastatic disease and non-metastatic curable disease. Similar to oligometastatic cancer, aggressive local treatment of meningioma oligometastases is warranted, as it may be curable. We present a patient with multiply recurrent intracranial meningiomas over 19 years, with a transformation from grade I to grade II histology, with oligometastatic disease to the C5 vertebral body. Three years following definitive spinal stereotactic radiosurgery, she remains without evidence of other metastatic diseases. Our case highlights the oncologic concept that metastatic meningioma need not be widely disseminated and provides the clinical rationale for aggressive local treatment of an oligometastatic meningioma.

12.
Clin Cancer Res ; 27(23): 6467-6478, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34475101

RESUMEN

PURPOSE: Pyruvate kinase M2 (PKM2) catalyzes the final step in glycolysis, a key process of cancer metabolism. PKM2 is preferentially expressed by glioblastoma (GBM) cells with minimal expression in healthy brain. We describe the development, validation, and translation of a novel PET tracer to study PKM2 in GBM. We evaluated 1-((2-fluoro-6-[18F]fluorophenyl)sulfonyl)-4-((4-methoxyphenyl)sulfonyl)piperazine ([18F]DASA-23) in cell culture, mouse models of GBM, healthy human volunteers, and patients with GBM. EXPERIMENTAL DESIGN: [18F]DASA-23 was synthesized with a molar activity of 100.47 ± 29.58 GBq/µmol and radiochemical purity >95%. We performed initial testing of [18F]DASA-23 in GBM cell culture and human GBM xenografts implanted orthotopically into mice. Next, we produced [18F]DASA-23 under FDA oversight, and evaluated it in healthy volunteers and a pilot cohort of patients with glioma. RESULTS: In mouse imaging studies, [18F]DASA-23 clearly delineated the U87 GBM from surrounding healthy brain tissue and had a tumor-to-brain ratio of 3.6 ± 0.5. In human volunteers, [18F]DASA-23 crossed the intact blood-brain barrier and was rapidly cleared. In patients with GBM, [18F]DASA-23 successfully outlined tumors visible on contrast-enhanced MRI. The uptake of [18F]DASA-23 was markedly elevated in GBMs compared with normal brain, and it identified a metabolic nonresponder within 1 week of treatment initiation. CONCLUSIONS: We developed and translated [18F]DASA-23 as a new tracer that demonstrated the visualization of aberrantly expressed PKM2 for the first time in human subjects. These results warrant further clinical evaluation of [18F]DASA-23 to assess its utility for imaging therapy-induced normalization of aberrant cancer metabolism.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Animales , Neoplasias Encefálicas/patología , Compuestos de Diazonio , Glioblastoma/patología , Glucólisis , Humanos , Ratones , Tomografía de Emisión de Positrones/métodos , Piruvato Quinasa/metabolismo , Ácidos Sulfanílicos
13.
J Proteome Res ; 9(5): 2610-8, 2010 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-20337498

RESUMEN

Approximately 50-80% of oligodendrogliomas demonstrate a combined loss of chromosome 1p and 19q. Chromosome 1p/19q deletion, appearing early in tumorigenesis, is associated with improved clinical outcomes, including response to chemotherapy and radiation. Although many hypotheses have been proposed, the molecular mechanisms underlying improved clinical outcomes with 1p/19q deletion in oligodendrogliomas have not been characterized fully. To investigate the molecular differences between oligodendrogliomas, we employed an unbiased proteomic approach using microcapillary liquid chromatography mass spectrometry, along with a quantitative technique called isotope-coded affinity tags, on patient samples of grade II oligodendrogliomas. Following conventional biochemical separation of pooled tumor tissue from five samples of undeleted and 1p/19q deleted grade II oligodendrogliomas into nuclei-, mitochondria-, and cytosol-enriched fractions, relative changes in protein abundance were quantified. Among the 442 total proteins identified, 163 nonredundant proteins displayed significant changes in relative abundance in at least one of the three fractions between oligodendroglioma with and without 1p/19q deletion. Bioinformatic analyses of differentially regulated proteins supported the potential importance of metabolism and invasion/migration to the codeleted phenotype. A subset of altered proteins, including the pro-invasive extracellular matrix protein BCAN, was further validated by Western blotting as candidate markers for the more aggressive undeleted phenotype. These studies demonstrate the utility of proteomic analysis to identify candidate biological motifs and molecular mechanisms that drive differential malignancy related to 1p19q phenotypes. Future analysis of larger patient samples are warranted to further refine biomarker panels to predict biological behavior and assist in the identification of deleted gene products that define the 1p/19q phenotype.


Asunto(s)
Aberraciones Cromosómicas , Cromosomas Humanos Par 19 , Cromosomas Humanos Par 1 , Eliminación de Gen , Oligodendroglioma/genética , Oligodendroglioma/metabolismo , Proteómica/métodos , Adulto , Anciano , Western Blotting , Cromatografía Liquida , Femenino , Humanos , Hibridación Fluorescente in Situ , Marcaje Isotópico , Masculino , Espectrometría de Masas , Persona de Mediana Edad , Reproducibilidad de los Resultados , Fracciones Subcelulares/química
14.
J Clin Neurosci ; 78: 413-415, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32631721

RESUMEN

Tenosynovial giant cell tumors (TGCTs) are benign neoplasms that arise from the synovium of tendon sheaths, bursae, and joints. We report a rare presentation of TGCT involving the suboccipital spine.


Asunto(s)
Neoplasias Encefálicas/patología , Tumores de Células Gigantes/patología , Membrana Sinovial/patología , Tumor de Células Gigantes de las Vainas Tendinosas/patología , Humanos , Lóbulo Occipital/patología , Neoplasias de la Columna Vertebral/patología
15.
Clin Cancer Res ; 26(1): 193-205, 2020 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-31615938

RESUMEN

PURPOSE: Most World Health Organization (WHO) grade I meningiomas carry a favorable prognosis. Some become clinically aggressive with recurrence, invasion, and resistance to conventional therapies (grade 1.5; recurrent/progressive WHO grade I tumors requiring further treatment within 10 years). We aimed to identify biomarker signatures in grade 1.5 meningiomas where histopathology and genetic evaluation has fallen short. EXPERIMENTAL DESIGN: Mass spectrometry (MS)-based phosphoproteomics and peptide chip array kinomics were used to compare grade I and 1.5 tumors. Ingenuity Pathway Analysis (IPA) identified alterations in signaling pathways with validation by Western blot analysis. The selected biomarker was evaluated in an independent cohort of 140 samples (79/140 genotyped for meningioma mutations) by tissue microarray and correlated with clinical variables. RESULTS: The MS-based phosphoproteomics revealed differential Ser/Thr phosphorylation in 32 phosphopeptides. The kinomic profiling by peptide chip array identified 10 phosphopeptides, including a 360% increase in phosphorylation of RB1, in the 1.5 group. IPA of the combined datasets and Western blot validation revealed regulation of AKT and cell-cycle checkpoint cascades. RB1 hyperphosphorylation at the S780 site distinguished grade 1.5 meningiomas in an independent cohort of 140 samples and was associated with decreased progression/recurrence-free survival. Mutations in NF2, TRAF7, SMO, KLF4, and AKT1 E17K did not predict RB1 S780 staining or progression in grade 1.5 meningiomas. CONCLUSIONS: RB1 S780 staining distinguishes grade 1.5 meningiomas, independent of histology, subtype, WHO grade, or genotype. This promising biomarker for risk stratification of histologically bland WHO grade I meningiomas provides insight into the pathways of oncogenesis driving these outlying clinically aggressive tumors.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Neoplasias Meníngeas/patología , Meningioma/patología , Recurrencia Local de Neoplasia/patología , Fosfoproteínas/metabolismo , Proteínas Quinasas/metabolismo , Proteínas de Unión a Retinoblastoma/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Progresión de la Enfermedad , Estudios de Seguimiento , Humanos , Factor 4 Similar a Kruppel , Espectrometría de Masas/métodos , Neoplasias Meníngeas/metabolismo , Meningioma/metabolismo , Clasificación del Tumor , Recurrencia Local de Neoplasia/metabolismo , Pronóstico , Proteoma/análisis , Proteoma/metabolismo , Factores de Riesgo , Transducción de Señal , Análisis de Matrices Tisulares/métodos
16.
Acta Neuropathol ; 117(3): 329-38, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19057918

RESUMEN

Transplantation of human fetal neural tissue into adult neostriatum is an experimental therapy for Huntington's disease (HD). Here we describe a patient with HD who received ten intrastriatal human fetal neural transplants and, at one site, an autologous sural nerve co-graft. Although initially clinically stable, she developed worsening asymmetric upper motor neuron symptoms in addition to progression of HD, and ultimately died 121 months post transplantation. Eight neural transplants, up to 2.9 cm, and three ependymal cysts, up to 2.0 cm, were identified. The autologous sural nerve co-graft was found adjacent to the largest mass lesion, which, along with the ependymal cyst, exhibited pronounced mass effect on the internal capsules bilaterally. Grafts were composed of neurons and glia embedded in disorganized neuropil; robust Y chromosome labeling was present in a subset of grafts and cysts. The graft-host border was discrete, and there was no evidence of graft rejection or HD pathologic changes within donor neurons. This report, for the first time, highlights the potential for graft overgrowth in a patient receiving fetal neural transplantation.


Asunto(s)
Trasplante de Tejido Encefálico/patología , Cuerpo Estriado/trasplante , Trasplante de Tejido Fetal/patología , Enfermedad de Huntington/terapia , Neuronas/patología , Células Madre , Adulto , Biomarcadores/análisis , Biomarcadores/química , Trasplante de Tejido Encefálico/inmunología , Trasplante de Tejido Encefálico/métodos , Cuerpo Estriado/patología , Cuerpo Estriado/fisiopatología , Resultado Fatal , Femenino , Trasplante de Tejido Fetal/inmunología , Trasplante de Tejido Fetal/métodos , Supervivencia de Injerto , Humanos , Enfermedad de Huntington/genética , Enfermedad de Huntington/fisiopatología , Neuroglía/metabolismo , Neuroglía/patología , Neuroglía/ultraestructura , Neuronas/metabolismo , Neuronas/ultraestructura , Insuficiencia del Tratamiento
17.
Cureus ; 11(4): e4541, 2019 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-31275768

RESUMEN

Multiple endocrine neoplasia type 1 (MEN-1) is an autosomal dominant disorder characterized by parathyroid, pancreatic islet, and pituitary tumors. Approximately 40% of MEN-1 patients harbor a pituitary adenoma. Separately, granular cell tumors (GCTs) of the sellar/parasellar region are an exceedingly rare clinical entity with less than 100 reported cases in the literature. These slow-growing, often asymptomatic lesions are difficult to diagnose and may mimic pituitary adenoma, Rathke cleft cyst, or other sellar/supra-sellar pathology. There is no known association with MEN-1 or any other familial syndrome. A 36-year-old neurologically normal woman with known MEN-1 underwent a screening magnetic resonance imaging (MRI) scan which revealed a 10 mm x 6 mm x 7 mm sellar/suprasellar lesion. She underwent endoscopic endonasal transsphenoidal resection. Subsequent neuropathological analysis was consistent with GCT of the pituitary gland. Here we describe the first report to our knowledge of a GCT of the pituitary gland occurring in a patient with MEN-1.

18.
J Neuropathol Exp Neurol ; 78(8): 694-702, 2019 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-31298284

RESUMEN

Brain tumors are the leading cause of death in children. Establishing an accurate diagnosis and therapy is critical for patient management. This study evaluated the clinical utility of GlioSeq, a next-generation sequencing (NGS) assay, for the diagnosis and management of pediatric and young adult patients with brain tumors. Between May 2015 and March 2017, 142 consecutive brain tumors were tested using GlioSeq v1 and subset using GlioSeq v2. Out of 142 samples, 63% were resection specimens and 37% were small stereotactic biopsies. GlioSeq sequencing was successful in 100% and 98.6% of the cases for the detection of mutations and copy number changes, and gene fusions, respectively. Average turnaround time was 8.7 days. Clinically significant genetic alterations were detected in 95%, 66.6%, and 66.1% of high-grade gliomas, medulloblastomas, and low-grade gliomas, respectively. GlioSeq enabled molecular-based stratification in 92 (65%) cases by specific molecular subtype assignment (70, 76.1%), substantiating a neuropathologic diagnosis (18, 19.6%), and diagnostic recategorization (4, 4.3%). Fifty-seven percent of the cases harbored therapeutically actionable findings. GlioSeq NGS analysis offers rapid detection of a wide range of genetic alterations across a spectrum of pediatric brain tumors using formalin-fixed, paraffin-embedded specimens and facilitates integrated molecular-morphologic classification and personalized management of pediatric brain tumors.

19.
Dev Neurosci ; 30(4): 276-84, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-17960055

RESUMEN

Previously we demonstrated that fetal alcohol exposure attenuates hypoxic cerebral vasodilation in fetal and neonatal sheep. One mechanism may be altered expression of brain vasoactive substances. We hypothesized that early fetal alcohol exposure alters the number of fetal neurons expressing vasoactive intestinal peptide (VIP), a potent cerebral vasodilator. Thirteen pregnant ewes received daily i.v. infusions of alcohol (1.5 g/kg) or saline on days 30-54 of gestation (term = 145 days). Fourteen fetal brains (6 alcohol-exposed, 8 saline control) were obtained on gestational day 126. Using unbiased stereology, we counted immunohistochemically-labeled VIP neurons in one half of each forebrain with an optical fractionator. The total NeuN-labeled neurons were similarly counted. Alcohol-exposed fetal sheep brains had fewer VIP-immunopositive neurons per hemisphere, 14.6 x 10(6), compared to saline controls, 19.8 x 10(6). The total neuron number was not different, 1.19 x 10(9) versus 1.23 x 10(9) respectively, indicating a selective decrease in VIP neurons as a result of alcohol exposure. In sheep, alcohol exposure early in gestation is associated with fewer VIP-producing neurons later in gestation compared to saline controls; therefore, alcohol-related changes in the number of VIP-expressing neurons may be responsible in part for the attenuated hypoxic cerebral vasodilation described in fetal and neonatal sheep exposed to alcohol earlier in gestation.


Asunto(s)
Trastornos del Espectro Alcohólico Fetal/metabolismo , Trastornos del Espectro Alcohólico Fetal/patología , Neuronas/metabolismo , Neuronas/patología , Péptido Intestinal Vasoactivo/metabolismo , Animales , Recuento de Células , Femenino , Edad Gestacional , Hipoxia Encefálica/metabolismo , Hipoxia Encefálica/patología , Inmunohistoquímica , Masculino , Embarazo , Prosencéfalo/citología , Prosencéfalo/embriología , Prosencéfalo/metabolismo , Ovinos
20.
Brain Res ; 1231: 75-80, 2008 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-18657528

RESUMEN

Heavy fetal alcohol exposure is associated with a spectrum of neurological abnormalities, although the mechanism of injury is largely unknown. We previously reported attenuated cerebral blood flow response to hypoxia in fetal and newborn sheep which were exposed to alcohol earlier in pregnancy. One possible mechanism for this effect of alcohol on the developing cerebral vasculature is a decrease in cerebral microvessel density, similar to its effect on developing neurons. Therefore, we tested the hypothesis that prenatal alcohol exposure decreases cerebral microvessel density. Pregnant ewes received intravenous infusions of ethanol or saline during days 60-84 of gestation (term=150 days) and at 125 days of gestation we obtained the fetal brains for study. We immunohistochemically labeled vessels of the left cerebral forebrain hemispheres with antibody to endothelial nitric oxide synthase and then obtained unbiased stereological estimates of cerebral microvessel density using a modified optical fractionator method. We studied 20 fetal brains of which 9 were alcohol-exposed, 11 were saline-controls, and all were products of a twin gestation. Although brain and body weights were not different between groups, the alcohol-exposed group had significantly lower brain weight as a percentage of body weight. Estimates of cerebral microvessel density were not significantly different between alcohol-exposed and saline-control groups: 12.7+/-8.7 and 9.1+/-2.8 microvessels per mm(3), respectively (mean+/-SD, p=0.32). Since there is no change in estimated cerebral microvessel density after prenatal alcohol exposure, we conclude that decreased cerebral microvessel density is not a likely explanation for attenuated cerebral blood flow in response to hypoxia.


Asunto(s)
Trastornos del Sistema Nervioso Inducidos por Alcohol/patología , Arterias Cerebrales/anomalías , Arterias Cerebrales/efectos de los fármacos , Trastornos del Espectro Alcohólico Fetal/patología , Microcirculación/efectos de los fármacos , Trastornos del Sistema Nervioso Inducidos por Alcohol/fisiopatología , Alcoholismo/complicaciones , Animales , Arteriolas/anomalías , Arteriolas/efectos de los fármacos , Arteriolas/fisiopatología , Depresores del Sistema Nervioso Central/toxicidad , Arterias Cerebrales/fisiopatología , Circulación Cerebrovascular/efectos de los fármacos , Modelos Animales de Enfermedad , Etanol/toxicidad , Femenino , Trastornos del Espectro Alcohólico Fetal/fisiopatología , Hipoxia Encefálica/fisiopatología , Masculino , Neovascularización Fisiológica/efectos de los fármacos , Óxido Nítrico Sintasa de Tipo III/efectos de los fármacos , Óxido Nítrico Sintasa de Tipo III/metabolismo , Tamaño de los Órganos/efectos de los fármacos , Embarazo , Segundo Trimestre del Embarazo/efectos de los fármacos , Prosencéfalo/irrigación sanguínea , Prosencéfalo/efectos de los fármacos , Prosencéfalo/fisiopatología , Ovinos
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