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1.
Cir Cir ; 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37156245

RESUMO

Rosai Dorfman Destombes (RDD) disease is a non-Langerhans histiocytosis. The central nervous system is affected in < 5% of cases. We report the case of a 59-year-old man, who began 8 months before admission with headache, diminished visual acuity in the temporal hemifields, hyposmia, and seizures. Magnetic resonance imaging showed three midline skull-base lesions in anterior, media, and posterior fossae. We performed a complete resection of symptomatic lesions using a bifrontal craniotomy. The histopathological analysis determined RDD, therefore, we started steroid treatment. Our case description is due to the diagnosis and location, one of the rarest reported to date in the literature.


La enfermedad de Rosai-Dorfman-Destombes (RDD) es una histiocitosis no Langerhans. El SNC se ve afectado en menos del 5% de los casos. Presentamos el caso de un hombre de 59 años quien inició ocho meses previos al ingreso con cefalea, hemianopsia bitemporal, hiposmia y convulsiones. La resonancia magnética mostró tres lesiones de la base del cráneo en las fosas anterior, media y posterior. Realizamos una resección completa de las lesiones sintomáticas mediante una craneotomía bifrontal. El análisis histopatológico determinó RDD. Nuestro caso es debido al diagnóstico y localización, uno de los más raros reportados hasta la fecha en la literatura.

2.
Cureus ; 14(8): e27711, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36081970

RESUMO

Tumors involving the pineal gland include germinomas, non-germinomatous, and parenchymal tumors. Sometimes these tumors can be differentiated into rhabdomyosarcoma, which is an aggressive and rapidly recurring sarcoma but is a rare event. We present the case of a 23-year-old male, with an eight-year-long history of a non-treated brain tumor compatible with a teratoma. Chemotherapy and radiotherapy were offered, and two years later, malignant transformation to astrocytoma, rhabdomyosarcoma, neural cell carcinoma, ganglioglioma, and low-grade chondrosarcoma was noted. Immunohistochemistry was valuable in differentiating these entities that confirmed the diagnosis. Malignant transformations may be secondary to the normal transformation of multipotent embryonic cells into more developed tissues after radiotherapy of teratoma and malignant ectomesenchymoma transformation.

3.
Int J Mol Sci ; 23(9)2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35563252

RESUMO

Corticotroph cells give rise to aggressive and rare pituitary neoplasms comprising ACTH-producing adenomas resulting in Cushing disease (CD), clinically silent ACTH adenomas (SCA), Crooke cell adenomas (CCA) and ACTH-producing carcinomas (CA). The molecular pathogenesis of these tumors is still poorly understood. To better understand the genomic landscape of all the lesions of the corticotroph lineage, we sequenced the whole exome of three SCA, one CCA, four ACTH-secreting PA causing CD, one corticotrophinoma occurring in a CD patient who developed Nelson syndrome after adrenalectomy and one patient with an ACTH-producing CA. The ACTH-producing CA was the lesion with the highest number of single nucleotide variants (SNV) in genes such as USP8, TP53, AURKA, EGFR, HSD3B1 and CDKN1A. The USP8 variant was found only in the ACTH-CA and in the corticotrophinoma occurring in a patient with Nelson syndrome. In CCA, SNV in TP53, EGFR, HSD3B1 and CDKN1A SNV were present. HSD3B1 and CDKN1A SNVs were present in all three SCA, whereas in two of these tumors SNV in TP53, AURKA and EGFR were found. None of the analyzed tumors showed SNV in USP48, BRAF, BRG1 or CABLES1. The amplification of 17q12 was found in all tumors, except for the ACTH-producing carcinoma. The four clinically functioning ACTH adenomas and the ACTH-CA shared the amplification of 10q11.22 and showed more copy-number variation (CNV) gains and single-nucleotide variations than the nonfunctioning tumors.


Assuntos
Adenoma Hipofisário Secretor de ACT , Adenoma , Carcinoma , Genômica , Síndrome de Nelson , Neoplasias Hipofisárias , Adenoma Hipofisário Secretor de ACT/genética , Adenoma/genética , Adenoma/patologia , Hormônio Adrenocorticotrópico , Aurora Quinase A , Carcinoma/genética , Corticotrofos/patologia , Receptores ErbB , Humanos , Melanocortinas , Complexos Multienzimáticos , Nucleotídeos , Neoplasias Hipofisárias/genética
4.
BMC Med Genomics ; 15(1): 52, 2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-35260162

RESUMO

BACKGROUND: Pituitary adenomas (PA) are the second most common intracranial tumors and are classified according to hormone they produce, and the transcription factors they express. The majority of PA occur sporadically, and their molecular pathogenesis is incompletely understood. METHODS: Here we performed transcriptome and proteome analysis of tumors derived from POU1F1 (GH-, TSH-, and PRL-tumors, N = 16), NR5A1 (gonadotropes and null cells adenomas, n = 17) and TBX19 (ACTH-tumors, n = 6) lineages as well as from silent ACTH-tumors (n = 3) to determine expression of kinases, cyclins, CDKs and CDK inhibitors. RESULTS: The expression profiles of genes encoding kinases were distinctive for each of the three PA lineage: NR5A1-derived tumors showed upregulation of ETNK2 and PIK3C2G and alterations in MAPK, ErbB and RAS signaling, POU1F1-derived adenomas showed upregulation of PIP5K1B and NEK10 and alterations in phosphatidylinositol, insulin and phospholipase D signaling pathways and TBX19-derived adenomas showed upregulation of MERTK and STK17B and alterations in VEGFA-VEGFR, EGF-EGFR and Insulin signaling pathways. In contrast, the expression of the different genes encoding cyclins, CDK and CDK inhibitors among NR5A1-, POU1F1- and TBX19-adenomas showed only subtle differences. CDK9 and CDK18 were upregulated in NR5A1-adenomas, whereas CDK4 and CDK7 were upregulated in POUF1-adenomas. CONCLUSIONS: The kinome of PA clusters these lesions into three distinct groups according to the transcription factor that drives their terminal differentiation. And these complexes could be harnessed as molecular therapy targets.


Assuntos
Adenoma , Neoplasias Hipofisárias , Adenoma/metabolismo , Hormônio Adrenocorticotrópico/genética , Proteínas Reguladoras de Apoptose/genética , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Ciclinas/genética , Ciclinas/metabolismo , Humanos , Insulina , Neoplasias Hipofisárias/genética , Neoplasias Hipofisárias/metabolismo , Neoplasias Hipofisárias/patologia , Proteínas Serina-Treonina Quinases , Fatores de Transcrição/genética , Transcriptoma
5.
Genes (Basel) ; 11(12)2020 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-33261069

RESUMO

BACKGROUND: Pituitary adenomas (PA) are the second most common tumor in the central nervous system and have low counts of mutated genes. Splicing occurs in 95% of the coding RNA. There is scarce information about the spliceosome and mRNA-isoforms in PA, and therefore we carried out proteomic and transcriptomic analysis to identify spliceosome components and mRNA isoforms in PA. METHODS: Proteomic profile analysis was carried out by nano-HPLC and mass spectrometry with a quadrupole time-of-flight mass spectrometer. The mRNA isoforms and transcriptomic profiles were carried out by microarray technology. With proteins and mRNA information we carried out Gene Ontology and exon level analysis to identify splicing-related events. RESULTS: Approximately 2000 proteins were identified in pituitary tumors. Spliceosome proteins such as SRSF1, U2AF1 and RBM42 among others were found in PA. These results were validated at mRNA level, which showed up-regulation of spliceosome genes in PA. Spliceosome-related genes segregate and categorize PA tumor subtypes. The PA showed alterations in CDK18 and THY1 mRNA isoforms which could be tumor specific. CONCLUSIONS: Spliceosome components are significant constituents of the PA molecular machinery and could be used as molecular markers and therapeutic targets. Splicing-related genes and mRNA-isoforms profiles characterize tumor subtypes.


Assuntos
Adenoma/metabolismo , Neoplasias Hipofisárias/metabolismo , Proteoma , Spliceossomos , Fator Esteroidogênico 1/genética , Fator de Transcrição Pit-1/genética , Transcriptoma , Adenoma/genética , Adenoma/patologia , Processamento Alternativo , Biomarcadores Tumorais , Linhagem da Célula , Cromatografia Líquida de Alta Pressão , Éxons/genética , Ontologia Genética , Hormônios/análise , Humanos , Nanotecnologia , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Análise de Sequência com Séries de Oligonucleotídeos , Neoplasias Hipofisárias/genética , Neoplasias Hipofisárias/patologia , Análise de Componente Principal , Isoformas de Proteínas/biossíntese , Isoformas de Proteínas/genética , RNA Mensageiro/biossíntese , RNA Neoplásico/biossíntese , Espectrometria de Massas em Tandem , Fatores de Transcrição/análise
6.
Sci Rep ; 10(1): 19373, 2020 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-33168897

RESUMO

Pituitary adenomas (PA) are the second most common intracranial tumors. These neoplasms are classified according to the hormone they produce. The majority of PA occur sporadically, and their molecular pathogenesis is incompletely understood. The present transcriptomic and methylomic analysis of PA revealed that they segregate into three molecular clusters according to the transcription factor driving their terminal differentiation. First cluster, driven by NR5A1, consists of clinically non-functioning PA (CNFPA), comprising gonadotrophinomas and null cell; the second cluster consists of clinically evident ACTH adenomas and silent corticotroph adenomas, driven by TBX19; and the third, POU1F1-driven TSH-, PRL- and GH-adenomas, segregated together. Genes such as CACNA2D4, EPHA4 and SLIT1, were upregulated in each of these three clusters, respectively. Pathway enrichment analysis revealed specific alterations of these clusters: calcium signaling pathway in CNFPA; renin-angiotensin system for ACTH-adenomas and fatty acid metabolism for the TSH-, PRL-, GH-cluster. Non-tumoral pituitary scRNAseq data confirmed that this clustering also occurs in normal cytodifferentiation. Deconvolution analysis identify potential mononuclear cell infiltrate in PA consists of dendritic, NK and mast cells. Our results are consistent with a divergent origin of PA, which segregate into three clusters that depend on the specific transcription factors driving late pituitary cytodifferentiation.


Assuntos
Epigenoma , Regulação Neoplásica da Expressão Gênica , Proteínas de Neoplasias , Neoplasias Hipofisárias , Transcriptoma , Células Dendríticas/metabolismo , Células Dendríticas/patologia , Feminino , Humanos , Células Matadoras Naturais/metabolismo , Células Matadoras Naturais/patologia , Masculino , Mastócitos/metabolismo , Mastócitos/patologia , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Neoplasias Hipofisárias/genética , Neoplasias Hipofisárias/metabolismo , Neoplasias Hipofisárias/patologia
7.
Cancer Biomark ; 28(2): 193-199, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32224525

RESUMO

BACKGROUND: Clinically non-functioning Pituitary Adenomas (NFPA) are among the most common neoplasms of the sellar region. They usually present with compressive symptoms such as headache and visual field defects and not infrequently, are found incidentally. NFPA are classified as gonadotropinomas, null cell adenomas, according to their immunohistochemical phenotype. The molecular alterations responsible for the development of these lesions are incompletely understood, and there is scarce information regarding the molecular alterations and markers. OBJECTIVE: We carried out an in-silico analysis aimed at identifying the molecular alterations in NFPA and to discover new molecular markers. METHODS: Twenty-three microarray libraries were analyzed. Fourteen correspond to NFPA and 9 to control tissue gland. They were analyzed using Partek Genomic Suite to identify differentially expressed genes and WebGestalt and Metascape to understand the meaning behind the gene lists. RESULTS: Pituitary adenomas showed a markedly different transcriptome compared to the non-tumoral gland, regardless of their putative immunophenotype. Genes related to calcium metabolism such as CACNA2D4, immune-related CXCR4, and stem cell-related KLF8 and PITX2 were altered. CONCLUSIONS: Differentially expressed calcium metabolism and immune-related genes in NFPA represent attractive molecular markers and potential therapeutic targets.


Assuntos
Adenoma/genética , Biomarcadores Tumorais/genética , Hipófise/patologia , Neoplasias Hipofisárias/genética , Adenoma/patologia , Canais de Cálcio Tipo L/genética , Biologia Computacional , Conjuntos de Dados como Assunto , Regulação Neoplásica da Expressão Gênica , Proteínas de Homeodomínio/genética , Humanos , Fatores de Transcrição Kruppel-Like/genética , Análise de Sequência com Séries de Oligonucleotídeos , Neoplasias Hipofisárias/patologia , Receptores CXCR4/genética , Fatores de Transcrição/genética , Proteína Homeobox PITX2
8.
Int J Mol Sci ; 21(6)2020 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-32183254

RESUMO

One of the characteristics of the cerebral aging process is the presence of chronic inflammation through glial cells, which is particularly significant in neurodegeneration. On the other hand, it has been demonstrated that the aryl hydrocarbon receptor (AHR) participates in the inflammatory response. Currently, evidence in animal models shows that the hallmarks of aging are associated with changes in the AHR levels. However, there is no information concerning the behavior and participation of AHR in the human aging brain or in Alzheimer's disease (AD). We evaluated the expression of AHR in human hippocampal post-mortem tissue and its association with reactive astrocytes by immunohistochemistry. Besides this, we analyzed through ELISA the AHR levels in blood serum from young and elder participants, and from AD patients. The levels of AHR and glial fibrillar acid protein were higher in elder than in young post-mortem brain samples. AHR was localized mainly in the cytosol of astrocytes and displayed a pattern that resembles extracellular vesicles; this latter feature was more conspicuous in AD subjects. We found higher serum levels of AHR in AD patients than in the other participants. These results suggest that AHR participates in the aging process, and probably in the development of neurodegenerative diseases like AD.


Assuntos
Doença de Alzheimer/metabolismo , Astrócitos/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/análise , Fatores de Transcrição Hélice-Alça-Hélice Básicos/sangue , Hipocampo/metabolismo , Receptores de Hidrocarboneto Arílico/análise , Receptores de Hidrocarboneto Arílico/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Animais , Ensaio de Imunoadsorção Enzimática , Vesículas Extracelulares/metabolismo , Feminino , Proteína Glial Fibrilar Ácida/análise , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Adulto Jovem
9.
Arch Med Res ; 50(7): 428-436, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31783305

RESUMO

AIMS: Gynaecological malignancies such as breast, ovarian and cervical cancers have become an important public health problem. Detection of molecular alterations in cancer research is fundamental since it can reveal specific pathogenic patterns and genes that could serve as markers. Our aim was to characterize common genomic and transcriptomic signatures for the three gynaecologic malignancies with the highest incidence and mortality to try to identify new molecular markers, therapeutic targets and molecular signatures. METHODS: Here we analysed a total of 723 microarray libraries corresponding to equal number of breast, ovary and cervical cancer and non-cancer patient samples. Copy number variation (CNV) was carried out using 428 libraries and transcriptomic analysis using the 295 remaining samples. RESULTS: Our results showed that breast, ovary and cervical malignancies are characterized by gain of 1q chromosome. At transcriptomic level, they share 351 coding and non-coding genes, which could represent core transcriptome of gynaecological malignancies. Pathway analysis from the resulting gene lists from CNV and expression showed participation in cell cycle, metabolism, and cell adhesion molecules among others. CONCLUSIONS: Chromosome 1q characterize the gynaecological malignancies, which could harbour a richness of genetic repertoire to mine for molecular markers and targets, particular gynaecologic expression profile, containing FANCI, FH and MIR155HG among others, could represent part of the transcriptomic core for diagnostic test and attractive therapeutic targets. It may not be long before every human cancer sample is profiled for a detections test to ascertain a molecular diagnosis and prognosis and to define an optimal and precise treatment strategy.


Assuntos
Biomarcadores/metabolismo , Perfilação da Expressão Gênica/métodos , Neoplasias dos Genitais Femininos/economia , Neoplasias dos Genitais Femininos/genética , Genômica/métodos , Medicina de Precisão/métodos , Transcriptoma/genética , Feminino , Humanos , Prognóstico
10.
Case Rep Pathol ; 2016: 6749590, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27313933

RESUMO

Haemangioblastomas are neoplasms of uncertain histogenesis with cellular and reticular variants advocated in current lore. Herein we describe an intriguing cerebellar specimen with unusual traits including spindle cell morphology and CD34 positivity. A thirty-nine-year old man had an infratentorial tumour discovered incidentally and resected three times. In all the instances, histopathological diagnosis was haemangioblastoma; nonetheless, he had neither physical stigmata nor family history of von Hippel-Lindau disease. By histology, the lesion was composed of areas of conventional stromal cells admixed with territories populated by short-spindled cells packed in lobules, sometimes giving the appearance of gomitoli. Immunoperoxidase-coupled reactions confirmed the expression of inhibin A, neuron-specific enolase (NSE), PS100, and CD57 but also revealed focal immunolabeling for CD34, CD99, and FXIIIa. This case highlights the potential phenotypical diversity that can be found within these neoplasms. Rather than uncertain histogenesis, it may in fact reflect multiple lines of differentiation-histomimesis-prone to adopt unusual morpho- and immunophenotypes in a subset of haemangioblastomas.

11.
J Pathol Transl Med ; 49(4): 325-30, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26081826

RESUMO

We report a 50-year-old woman with no relevant clinical history who presented with headache and loss of memory. Magnetic resonance imaging showed a left parieto-temporal mass with annular enhancement after contrast media administration, rendering a radiological diagnosis of high-grade astrocytic neoplasm. Tumour sampling was performed but the patient ultimately died as a result of disease. Microscopically, the lesion had areas of glioblastoma mixed with a benign mesenchymal constituent; the former showed hypercellularity, endothelial proliferation, high mitotic activity and necrosis, while the latter showed fascicles of long spindle cells surrounded by collagen and reticulin fibers. With approximately 40 previously reported cases, gliofibroma is a rare neoplasm defined as either glio-desmoplastic or glial/benign mesenchymal. As shown in our case, its prognosis is apparently determined by the degree of anaplasia of the glial component.

12.
J Pathol Transl Med ; 49(5): 403-8, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26081827

RESUMO

We report a unique case of a 4-year-old girl with an intriguing fibrohistiocytic tumour. Magnetic resonance imaging scans showed a dural mass of variegated intensity compressing the left occipital pole and apparently extending toward the superior sagittal sinus. Grossly, the cut surface of the surgical specimen was yellow, pale, and soft with reddish kernel-like crusts. Histologically, the yellow areas resembled cholesterol granulomas with widespread coagulative necrosis, cholesterol clefts, powdery calcification, foreign body-type giant cells, and foamy macrophages, while the scattered red spots contained numerous multinucleated giant cells of foreign-body and Touton types, the former with amphophilic to slightly eosinophilic cytoplasm. Immunoperoxidase reactions confirmed the expression of histiocytic markers and vimentin. As far as we know, no tumour displaying these peculiar morphological features has yet been described.

13.
PLoS One ; 7(7): e40070, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22808091

RESUMO

Ample animal studies demonstrate that neuropeptides NPY and α-MSH expressed in Arcuate Nucleus and Nucleus of the Tractus Solitarius, modulate glucose homeostasis and food intake. In contrast is the absence of data validating these observations for human disease. Here we compare the post mortem immunoreactivity of the metabolic neuropeptides NPY, αMSH and VGF in the infundibular nucleus, and brainstem of 11 type-2 diabetic and 11 non-diabetic individuals. α-MSH, NPY and tyrosine hydroxylase in human brain are localized in the same areas as in rodent brain. The similar distribution of NPY, α-MSH and VGF indicated that these neurons in the human brain may share similar functionality as in the rodent brain. The number of NPY and VGF immuno positive cells was increased in the infundibular nucleus of diabetic subjects in comparison to non-diabetic controls. In contrast, NPY and VGF were down regulated in the Nucleus of the Tractus Solitarius of diabetic patients. These results suggest an activation of NPY producing neurons in the arcuate nucleus, which, according to animal experimental studies, is related to a catabolic state and might be the basis for increased hepatic glucose production in type-2 diabetes.


Assuntos
Núcleo Arqueado do Hipotálamo/metabolismo , Diabetes Mellitus Tipo 2/genética , Fatores de Crescimento Neural/genética , Neurônios/metabolismo , Neuropeptídeo Y/genética , Núcleo Solitário/metabolismo , Adulto , Idoso , Núcleo Arqueado do Hipotálamo/patologia , Autopsia , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Feminino , Regulação da Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Fatores de Crescimento Neural/metabolismo , Neurônios/patologia , Neuropeptídeo Y/metabolismo , Núcleo Solitário/patologia , alfa-MSH/genética , alfa-MSH/metabolismo
14.
Radiographics ; 30(6): 1705-19, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21071384

RESUMO

Neurocysticercosis is a neurologic parasitic disease caused by the encysted larva of the tapeworm Taenia solium and is the most important parasitic disease of the human central nervous system. It is the most common cause of acquired epilepsy in endemic settings and constitutes a public health challenge for most of the developing world. Nowadays, however, as a result of globalization, neurocysticercosis is being seen more frequently in developed countries as well. Neurocysticercosis is acquired through fecal-oral contamination, and the disease course is complex, with two intermediate hosts (ie, pigs and humans) and a definitive host (humans). Traditionally, it has been classified into active and nonactive forms according to disease location. Radiologists must be aware of its imaging appearance, which is quite variable, as is the differential diagnosis. Imaging findings depend on several factors, including the stage of the life cycle of T solium at presentation; the number and location (ie, subarachnoid, cisternal, or intraventricular) of parasites; and associated complications such as vascular involvement (ie, arteritis with or without infarction), inflammatory response (ie, edema, gliosis, or arachnoiditis), and, in ventricular forms, degree of obstruction. Thus, the diagnostic approach, management, and prognosis for neurocysticercosis differ widely depending on the type of infection.


Assuntos
Diagnóstico por Imagem , Neurocisticercose/diagnóstico , Animais , Anti-Helmínticos/uso terapêutico , Diagnóstico Diferencial , Humanos , Estágios do Ciclo de Vida , Neurocisticercose/tratamento farmacológico , Neurocisticercose/epidemiologia , Neurocisticercose/fisiopatologia , Taenia solium/crescimento & desenvolvimento , Taenia solium/fisiologia
15.
Acta Neuropathol ; 116(5): 507-15, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18810470

RESUMO

In recent years, we have used a variety of tau immunological markers combined with the dye thiazin red (TR), an accurate marker to differentiate the fibrillar from the nonfibrillar state of both amyloid-beta and tau in Alzheimer's disease (AD). In this study, we used TR as a potential diagnostic marker of AD in frozen-thawed (F-T) brain tissue and imprint cytology. Control experiments included the use of Thioflavin-S staining, fixed tissue, and some double-labeled material with TR and selected tau markers, including AT100, MC1, Alz-50, TG-3, Tau-C3, and S396. Our results indicate that TR retains its strong affinity for both tangles and plaques in unfixed F-T tissue and imprint cytology. This information provides a potential use of TR as an accurate diagnostic tool for the rapid postmortem diagnosis of AD neuropathology. This study shows the advantages of TR on cytology mainly because tools for the fast postmortem diagnosis of AD are practically nonexistent. In addition, we observed Tau-C3 immunoreactivity in extracellular tangles, suggesting that the Tau-C3 epitope is characteristically stable. Moreover, this study demonstrates that chemical fixation is not necessarily required for tau immunoreactivity on histological sections.


Assuntos
Doença de Alzheimer/diagnóstico , Encéfalo/patologia , Neurônios/patologia , Placa Amiloide/patologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Benzotiazóis , Encéfalo/metabolismo , Feminino , Imunofluorescência/métodos , Humanos , Imuno-Histoquímica , Masculino , Microscopia Confocal , Pessoa de Meia-Idade , Emaranhados Neurofibrilares/metabolismo , Emaranhados Neurofibrilares/patologia , Neurônios/metabolismo , Compostos Orgânicos/metabolismo , Placa Amiloide/metabolismo , Mudanças Depois da Morte , Coloração pela Prata/métodos , Tiazóis/metabolismo , Proteínas tau/metabolismo
16.
J Alzheimers Dis ; 12(4): 365-75, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18198423

RESUMO

Neurofibrillary tangles (NFT) and dystrophic neurites represent dense cytoplasmic accumulations of abnormal polymers in the brain of patients with Alzheimer's disease (AD). These polymers are referred to as paired helical filaments (PHFs) whose main structural core is composed of tau protein. Tau processing has been associated with hyperphosphorylation and truncation that results in PHF assembly. Both molecular events appear to cause conformational change of tau molecules [11,17,32]. In this regard, in a previous work focused on the analysis of patterns of immunolabeling in pre-tangle cells, we found that regional changes precede the structural modifications in tau [32]. In the present study, we further analyzed the early stages of tau processing in pre-tangle cells by using a variety of immunological markers of specific N-terminus phosphorylation tau sites. We used AT100, TG-3, AT8, pT231, Alz-50, Tau-C3 and 423 antibodies that recognize different abnormal tau epitopes in AD brains. These antibodies were combined and analyzed using a confocal microscope. Our results indicate that the early stages of abnormal tau processing are characterized by a sequential appearance of specific phospho-dependent epitope. The cascade of appearance of the antibodies is: pT231 --> TG-3 --> AT8 -->AT100 --> Alz-50. In addition; truncation at Asp-421 of the C-terminus of tau protein, as detected by Tau-C3, is also an early molecular event in tau protein aggregation prior to PHF formation in AD.


Assuntos
Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Epitopos/metabolismo , Fosforilação , Proteínas tau/metabolismo , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/imunologia , Anticorpos/imunologia , Encéfalo/imunologia , Encéfalo/patologia , Humanos , Imuno-Histoquímica , Microscopia Confocal , Pessoa de Meia-Idade , Emaranhados Neurofibrilares/imunologia , Emaranhados Neurofibrilares/metabolismo , Emaranhados Neurofibrilares/patologia , Placa Amiloide/imunologia , Placa Amiloide/metabolismo , Placa Amiloide/patologia , Proteínas tau/imunologia
17.
J Alzheimers Dis ; 8(1): 29-41, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16155347

RESUMO

Neurofibrillary tangles (NFTs) are the neuropathological hallmarks in Alzheimer's disease (AD). Densities of NFTs correlate with the dementia status. NFTs reflect the intracellular accumulation of abnormal paired helical filaments (PHFs) composed of the microtubule-associated protein tau. Hyperphosphorylation and truncation have been proposed as key events leading to the genesis of PHFs. A recent hypothesis involving conformational changes has been emerging. These structural modifications of the tau protein were detected by monoclonal antibodies (mAbs) recognizing discontinuous epitopes along the tau molecule such as Alz-50, Tau-66 and MC1. A new mAb, TG-3, detects an early pathology in AD. The epitope of mAb TG-3 maps to phosphorylated Thr231 when the tau molecule is conformationally altered. In the present study, we used confocal microscopy to analyze the state of tau molecule adopting the TG-3 conformation during tangle formation. We also compared mAb TG-3 immunoreactivity with that of mAb Alz-50. Immunoelectronmicroscopy was also performed. N- and C- termini markers evidenced that the tau molecule is intact when it adopts the TG-3 conformation. In addition to NFT, mAb TG-3 also recognized NFT-not bearing-neurons suggesting an early processing of tau prior to NFT formation. Ultrastructural analysis evidenced the presence of TG-3 and Alz-50 immunoreactive products on organelles including mitochondria and endoplasmic reticulum. Nuclear heterochromatin was densely immunolabelled. These results together with the fact that TG-3 immunoreactivity is related to intact tau suggest that the conformation recognized by TG-3 is early staged in the neuronal pathology of AD. In addition, we document that the earliest changes in tau occur closely associated with organelles and heterochromatin.


Assuntos
Doença de Alzheimer/patologia , Anticorpos Monoclonais , Antígenos/imunologia , Citoesqueleto/patologia , Proteínas do Tecido Nervoso/metabolismo , Emaranhados Neurofibrilares/patologia , Idoso , Idoso de 80 Anos ou mais , Especificidade de Anticorpos , Córtex Entorrinal/patologia , Feminino , Hipocampo/patologia , Humanos , Masculino , Microscopia Confocal , Microscopia Imunoeletrônica , Pessoa de Meia-Idade , Neurônios/patologia , Fosforilação , Conformação Proteica , Proteínas tau
19.
Rev. méd. Hosp. Gen. Méx ; 63(1): 12-7, ene.-mar. 2000. ilus, tab, CD-ROM
Artigo em Espanhol | LILACS | ID: lil-294887

RESUMO

Se informan cuatro casos de esclerosis tuberosa. Los hallazgos post mortem más frecuentes fueron hamartomas subependimarios y angiofibromas faciales. También se encontraron astrocitomas subependimarios de células gigantes, rabdomiomas cardiacos múltiples, riñones poliquísticos, fibromas subungueales, manchas hipopigmentadas y angiomiolipomas renales. La presentación clínica y morfológica de la esclerosis tuberosa es variada y heterogénea y en esta breve serie se revisan los aspectos patológicos más importantes para su diagnóstico.


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Adulto , Esclerose Tuberosa/patologia , Angiofibroma/patologia , Angiofibroma/patologia
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