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1.
Neuromuscul Disord ; 33(6): 484-489, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37209493

RESUMO

Pathogenic variants in DNMT3A are most commonly associated with Tatton-Brown-Rahman Syndrome (TBRS), but includes other phenotypes such as Heyn-Sproul-Jackson syndrome and acute myeloid leukemia (AML). We describe a patient presenting to the neuromuscular clinic with a de novo missense variant in DNMT3A where the striking clinical feature is that of a congenital myopathy with associated episodes of rhabdomyolysis, severe myalgias and chest pain along with phenotypic features associated with TBRS. Muscle biopsy showed minor myopathic features and cardiac investigations revealed mildly impaired bi-ventricular systolic function. We confirmed the DNA methylation profile matched haplo-insufficient TBRS cases, consistent with a loss of methyltransferase activity. Our report emphasizes the phenotypic overlap of patients with syndromic disorders presenting to neuromuscular clinics and limitations of gene panels in establishing a molecular diagnosis.


Assuntos
Anormalidades Múltiplas , Deficiência Intelectual , Doenças Musculares , Rabdomiólise , Humanos , DNA (Citosina-5-)-Metiltransferases/genética , DNA Metiltransferase 3A , Mutação , Anormalidades Múltiplas/genética , Deficiência Intelectual/genética , Fenótipo , Rabdomiólise/diagnóstico , Rabdomiólise/genética
2.
Clin Transl Immunology ; 9(10): e1191, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33082953

RESUMO

OBJECTIVES: Targeted immunotherapies such as chimeric antigen receptor (CAR)-T cells are emerging as attractive treatment options for glioblastoma, but rely on identification of a suitable tumor antigen. We validated a new target antigen for glioblastoma, fibroblast activation protein (FAP), by undertaking a detailed expression study of human samples. METHODS: Glioblastoma and normal tissues were assessed using immunostaining, supported by analyses of published transcriptomic datasets. Short-term cultures of glioma neural stem (GNS) cells were compared to cultures of healthy astrocytes and neurons using flow cytometry. Glioblastoma tissues were dissociated and analysed by high-parameter flow cytometry and single-cell transcriptomics (scRNAseq). RESULTS: Compared to normal brain, FAP was overexpressed at the gene and protein level in a large percentage of glioblastoma tissues, with highest levels of expression associated with poorer prognosis. FAP was also overexpressed in several paediatric brain cancers. FAP was commonly expressed by cultured GNS cells but absent from normal neurons and astrocytes. Within glioblastoma tissues, the strongest expression of FAP was around blood vessels. In fact, almost every tumor vessel was highlighted by FAP expression, whereas normal tissue vessels and cultured endothelial cells (ECs) lacked expression. Single-cell analyses of dissociated tumors facilitated a detailed characterisation of the main cellular components of the glioblastoma microenvironment and revealed that vessel-localised FAP is because of expression on both ECs and pericytes. CONCLUSION: Fibroblast activation protein is expressed by multiple cell types within glioblastoma, highlighting it as an ideal immunotherapy antigen to target destruction of both tumor cells and their supporting vascular network.

3.
Mod Pathol ; 33(9): 1783-1790, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32366941

RESUMO

The 2018 iteration of the ASCO-CAP HER2 testing guidelines proposes significant changes with an emphasis on the integration of concurrent immunohistochemistry (IHC) and in situ hybridization (ISH). We wished to evaluate the impact of these changes on clinical practice. Between Jan 2012 to Feb 2017, 2132 consecutive invasive breast carcinomas were evaluated with IHC and ISH for HER2. The sample tested was the breast primary or axillary nodes in all but 57 (2.7%) distant metastases. For 1824 cases with both dual-probe ISH and IHC results, the ISH subgroup was 1: 299 (16.4%), 2: 19 (1.0%), 1.0%, 3: 6 (0.3%), 4: 48 (2.6%) and 5: 1452 (79.6%). Ultimately 21% of group 2 and 4 cases and 80% of group 4 cases were positive. The change in HER2 status between the 2018 vs 2013 was: amplified in 323 (15.2%) vs 15.5%; not amplified in 1804 (84.6%) vs 82.2%; equivocal in 0 vs 2.3% previously. In 22 of 2127 cases (1.03%) the 2013 and 2018 results were discordant, all in groups 2-4. The discrepant cases included 15 of 331 (4.5%) of 2013 amplified cancers, now negative (all in groups 2 or 3) and 7 of 1796 (0.4%) 2013 nonamplified cases, now positive (all in group 4). Because of routine testing with both IHC and ISH, we found 6 of 1147 (0.52%) IHC negative (0 or 1+) cases were amplified by ISH. Further, 19 of 289 (6.6%) of IHC 3+ cases were nonamplified by ISH, circumstances not covered by these guidelines. In summary at the population level, the 2018 ASCO-CAP guidelines have a 99% agreement with the 2013 results. A major advantage is the abolishment of the clinically problematic equivocal category. Routine performance of both IHC and ISH uncovers a small proportion of cancers whose HER2 status is not addressed by these guidelines.


Assuntos
Neoplasias da Mama/metabolismo , Mama/metabolismo , Receptor ErbB-2/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Mama/patologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Feminino , Humanos , Imuno-Histoquímica , Hibridização In Situ , Guias de Prática Clínica como Assunto , Receptor ErbB-2/genética
4.
Transpl Infect Dis ; 22(3): e13293, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32291834

RESUMO

BACKGROUND: Progressive multifocal leukoencephalopathy (PML) is a rare demyelinating disease of the central nervous system caused by JC virus (JCV). The disease occurs in the setting of significant immunocompromise and has now been reported in many different settings, although only very rarely after lung transplantation. The mortality rate is high and therapeutic options are limited. CASE PRESENTATION: We report a case of a 66-year-old man who presented with non-specific memory disturbance at 19 months after lung transplantation for chronic hypersensitivity pneumonitis. He had required methylprednisolone for acute allograft rejection but achieved good graft function. Physical examination was unremarkable. CT revealed hypodensity in the left frontal lobe. MR demonstrated significant hyperintense white-matter abnormalities on T2-weighted and fluid-attenuated inversion recovery (FLAIR) sequences, mainly focused on the periventricular region adjacent the frontal horn of the left lateral ventricle. Brain biopsy confirmed PML. The patient had his immunosuppression reduced but then developed antibody-mediated rejection four months later. Despite re-escalation of immunosuppression, he remains neurologically stable on mirtazapine at eight months post-diagnosis. CONCLUSIONS: This very rare case highlights the challenges presented by PML, especially in the lung transplant population. It reveals the difficult balance between reducing immunosuppression to protect the brain versus prevention of lung allograft rejection. It clearly highlights the need for improved therapeutic modalities.


Assuntos
Encéfalo/diagnóstico por imagem , Leucoencefalopatia Multifocal Progressiva/diagnóstico , Transplante de Pulmão/efeitos adversos , Transtornos da Memória/virologia , Adulto , Idoso , Biópsia , Encéfalo/patologia , Encéfalo/virologia , Feminino , Humanos , Leucoencefalopatia Multifocal Progressiva/virologia , Masculino , Transtornos da Memória/diagnóstico , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
5.
Med Biol Eng Comput ; 58(5): 1031-1045, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32124225

RESUMO

Histopathological whole slide images of haematoxylin and eosin (H&E)-stained biopsies contain valuable information with relation to cancer disease and its clinical outcomes. Still, there are no highly accurate automated methods to correlate histolopathological images with brain cancer patients' survival, which can help in scheduling patients therapeutic treatment and allocate time for preclinical studies to guide personalized treatments. We now propose a new classifier, namely, DeepSurvNet powered by deep convolutional neural networks, to accurately classify in 4 classes brain cancer patients' survival rate based on histopathological images (class I, 0-6 months; class II, 6-12 months; class III, 12-24 months; and class IV, >24 months survival after diagnosis). After training and testing of DeepSurvNet model on a public brain cancer dataset, The Cancer Genome Atlas, we have generalized it using independent testing on unseen samples. Using DeepSurvNet, we obtained precisions of 0.99 and 0.8 in the testing phases on the mentioned datasets, respectively, which shows DeepSurvNet is a reliable classifier for brain cancer patients' survival rate classification based on histopathological images. Finally, analysis of the frequency of mutations revealed differences in terms of frequency and type of genes associated to each class, supporting the idea of a different genetic fingerprint associated to patient survival. We conclude that DeepSurvNet constitutes a new artificial intelligence tool to assess the survival rate in brain cancer. Graphical abstract A DCNN model was generated to accurately predict survival rates of brain cancer patients (classified in 4 different classes) accurately. After training the model using images from H&E stained tissue biopsies from The Cancer Genome Atlas database (TCGA, left), the model can predict for each patient, based on a histological image (top right), its survival class accurately (bottom right).


Assuntos
Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Interpretação de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Aprendizado Profundo , Histocitoquímica , Humanos , Análise de Sobrevida
6.
Muscle Nerve ; 61(5): 570-574, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32035011

RESUMO

Herein we report a case of sporadic inclusion-body myositis (sIBM) occurring at an unusually young age in a patient with primary Sjögren syndrome, and use the case to explore possible shared mechanisms for disease susceptibility. Possible factors may include the association of both conditions with the 8.1 ancestral haplotype; the presence of anti-cN1A antibodies, which, although considered specific for sIBM, are also seen in pSS; and the shared association with T-cell large granular lymphocyte leukemia (T-LGLL). Further evaluation of this patient did in fact reveal underlying T-LGLL and mechanisms by which T cells in sIBM may escape immune regulation and contribute to disease phenotype are explored. Despite myofiber infiltration with CD8-positive T cells in sIBM, and, although sIBM is traditionally considered treatment-refractory, we report a significant response to the anti-CD20 monoclonal antibody, rituximab, and discuss possible mechanisms by which this response may be mediated.


Assuntos
5'-Nucleotidase/imunologia , Autoanticorpos/imunologia , Leucemia Linfocítica Granular Grande/imunologia , Miosite de Corpos de Inclusão/imunologia , Síndrome de Sjogren/imunologia , Adulto , Azatioprina/uso terapêutico , Linfócitos T CD8-Positivos/patologia , Feminino , Antígenos HLA/genética , Haplótipos , Humanos , Hidroxicloroquina/uso terapêutico , Imunoglobulinas Intravenosas/uso terapêutico , Fatores Imunológicos/uso terapêutico , Leucemia Linfocítica Granular Grande/complicações , Imageamento por Ressonância Magnética , Metotrexato/uso terapêutico , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/patologia , Miosite de Corpos de Inclusão/complicações , Miosite de Corpos de Inclusão/patologia , Miosite de Corpos de Inclusão/terapia , Prednisolona/uso terapêutico , Rituximab/uso terapêutico , Síndrome de Sjogren/complicações , Síndrome de Sjogren/terapia
7.
Endocr Pathol ; 30(4): 318-328, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31473917

RESUMO

Somatic GNAS and USP8 mutations have been implicated in sporadic somatotrophinomas and corticotrophinomas, respectively. However, no genes are known to be recurrently mutated in sporadic prolactinomas. The prevalence of copy number variants (CNV), which is emerging as a mechanism of tumorigenesis in sporadic pituitary adenomas in general, is also unclear in prolactinomas. To characterize the genetic events underpinning sporadic prolactinomas, we performed whole exome sequencing of paired tumor and germline DNA from 12 prolactinoma patients. We observed recurrent large-scale CNV, most commonly in the form of copy number gains. We also identified sequence variants of interest in 15 genes. This included the DRD2, PRL, TMEM67, and MLH3 genes with plausible links to prolactinoma formation. Of the 15 genes of interest, CNV was seen at the gene locus in the corresponding tumor in 10 cases, and pituitary expression of eight genes was in the top 10% of tissues. However, none of our shortlisted somatic variants appeared to be classical driver mutations as no variant was found in more than one tumor. Future directions of research include mechanistic studies to investigate how CNV may contribute to prolactinoma formation, larger studies of relevant prolactinoma subsets according to clinical characteristics, and additional genetic investigations for aberrations not captured by whole exome sequencing.


Assuntos
Neoplasias Hipofisárias/genética , Prolactinoma/genética , Adolescente , Adulto , Idoso , Variações do Número de Cópias de DNA , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
Biochem Soc Trans ; 47(2): 625-638, 2019 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-30902924

RESUMO

Glioblastoma is the deadliest form of brain cancer. Aside from inadequate treatment options, one of the main reasons glioblastoma is so lethal is the rapid growth of tumour cells coupled with continuous cell invasion into surrounding healthy brain tissue. Significant intra- and inter-tumour heterogeneity associated with differences in the corresponding tumour microenvironments contributes greatly to glioblastoma progression. Within this tumour microenvironment, the extracellular matrix profoundly influences the way cancer cells become invasive, and changes to extracellular (pH and oxygen levels) and metabolic (glucose and lactate) components support glioblastoma growth. Furthermore, studies on clinical samples have revealed that the tumour microenvironment is highly immunosuppressive which contributes to failure in immunotherapy treatments. Although technically possible, many components of the tumour microenvironment have not yet been the focus of glioblastoma therapies, despite growing evidence of its importance to glioblastoma malignancy. Here, we review recent progress in the characterisation of the glioblastoma tumour microenvironment and the sources of tumour heterogeneity in human clinical material. We also discuss the latest advances in technologies for personalised and in vitro preclinical studies using brain organoid models to better model glioblastoma and its interactions with the surrounding healthy brain tissue, which may play an essential role in developing new and more personalised treatments for this aggressive type of cancer.


Assuntos
Encéfalo/citologia , Glioblastoma/metabolismo , Microambiente Tumoral/fisiologia , Animais , Biópsia , Encéfalo/patologia , Humanos
9.
Muscle Nerve ; 58(6): 790-795, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30194844

RESUMO

Introduction,: Graft-versus-host disease (GVHD) is a recognized complication of allogeneic stem cell transplantation (allo-SCT) and may affect muscle. We investigated the incidence and subtypes of inflammatory myopathy (IM) in South Australian recipients of allo-SCT. METHODS: Recipients of allo-SCT from 2004 to 2014 at the Royal Adelaide Hospital were identified. Records were reviewed to identify patients with weakness, creatine kinase (CK) elevation, and muscle biopsy confirming IM. RESULTS: Weakness was present in 32 of 224 patients who received allo-SCT patients reviewed, and CK was raised in 7 of 20 patients with weakness. Six patients developed biopsy-confirmed IM; 3 patients had chronic GVHD-related myopathy, 2 had necrotizing myopathy, and 1 had dermatomyositis (DM) associated with anti-melanoma differentiation associated protein 5 (MDA5) antibodies. The incidence of IM was calculated to be 2 cases per thousand annually. DISCUSSION: Among recipients of allo-SCT, weakness is common, and the incidence of IM is increased. Histopathological diagnoses are varied, and we report findings of necrotizing myopathy and anti-MDA5-associated DM. Muscle Nerve 58:790-795, 2018.


Assuntos
Doença Enxerto-Hospedeiro/etiologia , Miosite/etiologia , Complicações Pós-Operatórias/etiologia , Transplante de Células-Tronco/efeitos adversos , Adolescente , Adulto , Idoso , Aloenxertos/metabolismo , Antígenos CD/metabolismo , Austrália , Creatina Quinase/sangue , Eletromiografia , Feminino , Antígenos de Histocompatibilidade/metabolismo , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Debilidade Muscular/etiologia , Miosite/epidemiologia , Prevalência , Estudos Retrospectivos , Adulto Jovem
10.
Muscle Nerve ; 56(5): 987-989, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28224635

RESUMO

INTRODUCTION: The role of vaccinations and infections in triggering idiopathic inflammatory myopathies (IIM) has not been confirmed. METHODS: Among patients with histologically confirmed myositis, infections or vaccinations administered prior to myositis onset were determined. The characteristics of this group were compared with controls (myositis patients without prior infection or vaccination). RESULTS: The frequency of IIM with a prior vaccination was 20 of 206 (9.7%), infection was 29 of 206 (14%), and either vaccination or infection was 49 of 206 (23.8%). Dermatomyositis (DM) was more frequent among patients with preceding vaccination (P = 0.03) or prior infections (P = 0.02) than among controls. Antibodies to Ro52 were more frequent among patients with preceding vaccination than among controls (P = 0.002). DISCUSSION: Although causality is not shown, the occurrence of prior infection or vaccination in 24% of patients with IIM prompts further inquiry. The overrepresentation of DM in those with preceding vaccination and the possible role of antibodies to Ro52 in susceptibility to vaccine-induced myositis require confirmation. Muscle Nerve 56: 987-989, 2017.


Assuntos
Infecções/etiologia , Miosite/epidemiologia , Miosite/etiologia , Vacinação/efeitos adversos , Adulto , Austrália/epidemiologia , Autoanticorpos/sangue , Feminino , Humanos , Masculino , Ribonucleoproteínas/imunologia
11.
Clin Rheumatol ; 36(3): 689-693, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27629259

RESUMO

The clinical significance of curvilinear bodies (CB) seen in association with hydroxychloroquine (HCQ) therapy is uncertain. Patients with CB on muscle biopsy performed between 2006 and the present were identified, and their clinical features including body mass index and cumulative HCQ dose were recorded. A control group of 16 patients with idiopathic inflammatory myositis (IIM) on HCQ at time of biopsy but without evidence of CB was identified. Nineteen patients with CB were identified; details were available for 18. Among patients with CB, 7/18 also had IIM. Seven out of ten patients with CB who did not have IIM or MHCI/II expression had proximal weakness; 7/11 had raised serum creatinine kinase (CK) levels. There was no difference in body weight (p = 0.47), body mass index (p = 0.93), cumulative HCQ dose (p = 0.52) or cumulative dose adjusted for body weight (p = 0.39) or body mass index (p = 0.32) between patients with CB and controls. Patients with CB had lower median CK levels than controls (p = 0.034). Weakness was present in 12/17 patients and 12/16 controls (p = 1.0). Concurrent proton-pump inhibitors were co-prescribed in 12/18 (67 %) patients with CB and in 6/16 (38 %) controls (p = 0.17). Development of CB does not appear to be related to cumulative HCQ dose or body weight. Patients with CB frequently have muscle weakness in the absence of MHC1 expression suggesting a role for non-immune mechanisms of muscle injury. A high proportion of patients with CB are co-prescribed proton-pump inhibitors raising the possibility that co-prescription of both agents may disrupt lysosomal function and adversely affect muscle function.


Assuntos
Antirreumáticos/efeitos adversos , Hidroxicloroquina/efeitos adversos , Debilidade Muscular/induzido quimicamente , Músculo Esquelético/patologia , Miosite/tratamento farmacológico , Antirreumáticos/uso terapêutico , Bases de Dados Factuais , Humanos , Hidroxicloroquina/uso terapêutico , Debilidade Muscular/patologia , Miosite/patologia
14.
Pathology ; 43(2): 88-92, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21233669

RESUMO

This review highlights the recent changes to the World Health Organization (WHO) 4th edition of the classification of central nervous system tumours. The mixed glial and neuronal tumour group continues to expand to encompass three new subtypes of glioneuronal tumours. The main diagnostic points differentiating these tumours are covered. Also covered is an update on issues relating to grading of astrocytic, oligodendroglial and pineal tumours and the recent molecular subtypes observed in medulloblastomas. The theme of molecular genetics is continued in the following section where the four subtypes in the molecular subclassification of glioblastoma; classical, mesenchymal, proneural and neural are outlined. The genetic profile of these subtypes is highlighted as is their varying biological responses to adjuvant therapies. The relationship between chromosome 1p and 19q deletions and treatment responsive oligodendrogliomas is discussed, as are the newer advances relating to silencing of the MGMT gene in astrocytomas and mutations in the IDH-1 gene in both astrocytomas and oligodendrogliomas. The final section in this article provides an update on the concept of glioma stem cells.


Assuntos
Astrocitoma/diagnóstico , Neoplasias Encefálicas/diagnóstico , Oligodendroglioma/diagnóstico , Astrocitoma/classificação , Astrocitoma/genética , Neoplasias Encefálicas/classificação , Neoplasias Encefálicas/genética , Aberrações Cromossômicas , Cromossomos Humanos Par 1 , Cromossomos Humanos Par 19 , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Inativação Gênica , Humanos , Isocitrato Desidrogenase/genética , Biologia Molecular , Mutação , Células-Tronco Neoplásicas/patologia , Oligodendroglioma/classificação , Oligodendroglioma/genética , Patologia Molecular , Proteínas Supressoras de Tumor/genética , Organização Mundial da Saúde
15.
J Forensic Leg Med ; 15(4): 205-9, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18423350

RESUMO

Although Marfan syndrome has a range of characteristic morphological features involving the ocular, cardiovascular and musculoskeletal systems, the phenotype is variable. In addition, mutations have been identified in the gene encoding for fibrillin-1 and also in the transforming growth factor-beta receptor 2 (TGF-betaR2) gene. Two cases are presented of sudden and unexpected deaths in cousins who manifested morphologic features of Marfan syndrome at autopsy. Case 1: A 36-year-old male who collapsed and was found at autopsy to have arachnodactyly, a high arched palate and lethal aortic dissection with haemopericardium. Case 2: A 34-year-old male who collapsed and was found at autopsy to have arachnodactyly, a high arched palate, pes cavus and a dysplastic mitral valve. Current aetiological theories and molecular findings are discussed. While family follow-up and counselling are advised when cases come to autopsy, given the variability in phenotype and genotype, and the difficulties that exist in attempting to determine clinical prognosis from either of these, such deaths may raise more concerns for surviving family members than providing answers.


Assuntos
Morte Súbita/etiologia , Síndrome de Marfan/genética , Síndrome de Marfan/patologia , Adulto , Dissecção Aórtica/patologia , Aneurisma Aórtico/patologia , Aracnodactilia/patologia , Tamponamento Cardíaco/etiologia , Doença da Artéria Coronariana/patologia , Deformidades do Pé/patologia , Patologia Legal , Humanos , Masculino , Valva Mitral/anormalidades , Valva Mitral/patologia , Prolapso da Valva Mitral/etiologia , Palato/anormalidades , Derrame Pericárdico/patologia
16.
Forensic Sci Med Pathol ; 2(4): 269-72, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25868773

RESUMO

Injuries to bodies from animal activity are often postmortem in nature, although differentiating ante- from postmortem tissue damage may be difficult. Presented here is the case of a 73-year-old woman who died of a cerebral infarct. The woman demonstrated postmortem, and probable premortem, injuries resulting from rodent activity. Histological examination of tissues from areas of animal activity revealed a subtle early vital reaction, suggesting that the victim may have been alive during the animal feeding activity. Given the Polish folk legend of Popiel, a ninth-century ruler who was eaten alive by mice, the finding of antemortem injuries due to rodents or other animals could be designated the "Popiel phenomenon." Histological assessment of such wounds may be a crucial step in determining the timing of injuries, helping to elucidate the chronology of the fatal event, and separating pre- from postmortem wounds. If a vital reaction is detected, it can be assumed that the victim was alive for some time in an incapacitated state prior to death, and that death did not occur rapidly.

17.
J Neurotrauma ; 21(11): 1562-72, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15684649

RESUMO

The aim of these studies was to assess and quantitate the effects of cyclosporin-A (CyA) on brain APP messenger RNA and neuronal perikaryal APP antigen expression following controlled focal head impact in sheep. Impact results in a significant increase in both APP mRNA and neuronal perikaryal APP antigen expression. Post-traumatic administration of CyA (intrathecal 10 mg/kg) resulted in a reduction in APP mRNA and neuronal perikaryal antigen expression. At 2 h postinjury, CyA treatment caused a statistically significant (p < 0.05) 1.3 +/- 0.1-fold decrease in APP mRNA in the central gray matter of impacted sheep compared to untreated impacted sheep. A more profound reduction in APP mRNA synthesis (1.6 +/- 0.2 fold) was evident at 6 h (p < 0.05). The mean percentage brain area with APP immunoreactive neuronal perikarya at 6 h post-injury was 94.5% in untreated impacted animals, 10.0% in CyA-treated impacted animals, 5.5% in untreated nonimpacted animals, and 6% in CyA-treated non-impacted controls. These results demonstrate that CyA has a downregulatory effect on increased APP expression caused by TBI.


Assuntos
Precursor de Proteína beta-Amiloide/genética , Lesões Encefálicas/tratamento farmacológico , Encéfalo/efeitos dos fármacos , Ciclosporina/farmacologia , Degeneração Neural/tratamento farmacológico , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Lesões Encefálicas/metabolismo , Lesões Encefálicas/fisiopatologia , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/fisiologia , Feminino , Imuno-Histoquímica , Injeções Espinhais , Degeneração Neural/fisiopatologia , Degeneração Neural/prevenção & controle , Fármacos Neuroprotetores/farmacologia , RNA Mensageiro/antagonistas & inibidores , RNA Mensageiro/metabolismo , Ovinos , Fatores de Tempo , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/fisiologia
18.
Pathology ; 35(3): 224-7, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-14506966
19.
Am J Forensic Med Pathol ; 24(2): 114-8, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12773844

RESUMO

The case is presented of a 19-year-old man who was assaulted and died shortly afterward from a large traumatic basal subarachnoid hemorrhage (TBSAH) that arose from rupture of the left vertebral artery, proximal to the point at which the artery penetrated the dura. The literature regarding TBSAH and vertebral artery rupture is reviewed, and a number of points are highlighted: patients with TBSAH may remain conscious for a period of hours after injury, subcutaneous or muscular bruising may be contralateral to the ruptured vessel, fractures of the transverse processes of the cervical vertebrae and significant pathology of the vertebral artery are not typically associated with TBSAH, and rupture of the vertebral artery may be intracranial, junctional, or extracranial.


Assuntos
Traumatismos Craniocerebrais/patologia , Traumatismo Múltiplo/patologia , Hemorragia Subaracnoídea Traumática/patologia , Artéria Vertebral/lesões , Adulto , Evolução Fatal , Humanos , Masculino , Ruptura/patologia , Violência
20.
Spine (Phila Pa 1976) ; 27(19): 2088-94, 2002 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-12394919

RESUMO

STUDY DESIGN: Particles of a proprietary polyolefin rubber compound used in a lumbar disc prosthesis were generated in vitro and tested for biocompatibility in two animal models. OBJECTIVE To characterize any tissue response to polyolefin rubber particles. SUMMARY OF BACKGROUND DATA: Intervertebral disc prostheses are emerging as alternatives to fusion techniques for the treatment of symptomatic disc degeneration. The biocompatibility of all novel components used in the construction of these devices must be verified before they can be considered for general use. METHODS: Laboratory-generated polyolefin rubber particles were either injected into dorsal subcutaneous air pouches of 30 rats or placed directly onto the lumbosacral dura and nerve roots of 9 sheep. Histologic sections of tissues from, and remote from, the site of implantation were examined for evidence of inflammation and wound-healing responses. RESULTS: Polyolefin rubber particle debris induced a tissue response that was consistent with a normal foreign body reaction to large particles. The response was not significantly greater than that seen with similar size particles of ultrahigh molecular weight polyethylene. There was no evidence of particle migration from the site of implantation, and there was no evidence of local or systemic toxic effects. CONCLUSION: Polyolefin rubber particles induce only localized tissue response that is consistent with a normal foreign body reaction to large nontoxic particles.


Assuntos
Falha de Equipamento/estatística & dados numéricos , Reação a Corpo Estranho/etiologia , Implantes Experimentais/efeitos adversos , Disco Intervertebral , Teste de Materiais/estatística & dados numéricos , Animais , Procedimentos Cirúrgicos Dermatológicos , Vias de Administração de Medicamentos , Dura-Máter/efeitos dos fármacos , Dura-Máter/patologia , Análise de Falha de Equipamento , Reação a Corpo Estranho/patologia , Implantes Experimentais/estatística & dados numéricos , Disco Intervertebral/cirurgia , Deslocamento do Disco Intervertebral/etiologia , Deslocamento do Disco Intervertebral/cirurgia , Laminectomia , Região Lombossacral , Masculino , Microesferas , Modelos Animais , Tamanho da Partícula , Polienos/química , Polienos/farmacologia , Polietilenos/química , Polietilenos/farmacologia , Ratos , Ratos Endogâmicos , Borracha/química , Borracha/farmacologia , Ovinos , Pele/patologia , Raízes Nervosas Espinhais/efeitos dos fármacos , Raízes Nervosas Espinhais/patologia
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