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1.
Braz J Med Biol Res ; 53(2): e8962, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32022102

RESUMO

The aims of this study were to evaluate the intra- and interobserver reproducibility of manual segmentation of bone sarcomas in magnetic resonance imaging (MRI) studies and to compare manual and semiautomatic segmentation methods. This retrospective study included twelve osteosarcoma and eight Ewing sarcoma MRI studies performed prior to any therapeutic intervention. All cases were histopathologically confirmed. Three radiologists used 3D-Slicer software to perform manual segmentation of bone sarcomas in a blinded and independent manner. One radiologist segmented manually and also performed semiautomatic segmentation with the GrowCut tool. Segmentation exercises were timed for comparison. The dice similarity coefficient (DSC) and Hausdorff distance (HD) were used to evaluate similarity between the segmentation results and further statistical analyses were performed to compare DSC, HD, and volumetric results. Manual segmentation was reproducible with intraobserver DSC varying from 0.83 to 0.97 and HD from 3.37 to 28.73 mm. Interobserver DSC of manual segmentation showed variation from 0.73 to 0.97 and HD from 3.93 to 33.40 mm. Semiautomatic segmentation compared to manual segmentation resulted in DSCs of 0.71-0.96 and HDs of 5.38-31.54 mm. Semiautomatic segmentation required significantly less time compared to manual segmentation (P value ≤0.05). Among all situations compared, tumor volumetry did not show significant statistical differences (P value >0.05). We found excellent intra- and interobserver agreement for manual segmentation of osteosarcoma and Ewing sarcoma. There was high similarity between manual and semiautomatic segmentation, with a significant reduction of segmentation time using the semiautomatic method.


Assuntos
Neoplasias Ósseas/diagnóstico por imagem , Osteossarcoma/diagnóstico por imagem , Sarcoma de Ewing/diagnóstico por imagem , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Estudos Retrospectivos , Adulto Jovem
2.
Pathol Oncol Res ; 26(1): 133-139, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29270775

RESUMO

Over the last decade, the rho-associated kinases and several metastasis-associated microRNAs have emerged as important contributors of tumor invasion. However, despite prominence, our understanding of their involvement in the metastatic potential of Ewing Sarcoma (EWS) is incomplete. The expression profiles of ROCK1 or ROCK2 and miR-124-3p, miR-138-5p, miR-139-5p, miR-335-5p and miR-584-5p (all of which were previously predicted or validated to regulate these kinases) were evaluated through qRT-PCR and associated with clinical parameters. In vitro assays to evaluate colony formation and invasion/migration capacieties were performed on SK-ES-1 cells transfected with pre-miR mimics. ROCK1 expression was significantly reduced in EWS tissues, though there was no association with pathological parameters. miR-124-3p, miR-139-5p and miR-335-3p were also found significantly downregulated and positively correlated with ROCK1. Stratification indicated an association between lower levels of miR-139-5p and miR-584-5p with disease progression (p < 0.05), while reduced expression of the former and miR-124-3p were associated with reduced survival. In vitro miR-139-5p overexpression yielded inconsistent results: while mir-139-5p restoration significantly reduced invasion, the clonogenic capacity of cells was increased. Our study demonstrated that down-regulation of miR-124-3p, miR-139-5p and miR-584-5p are associated with disease progression in EWS and may serve as a risk assessment biomarkers though, as seen for mir-139-5p, their specific role remain to be elucidated for considering tailoring treatment options.


Assuntos
Neoplasias Ósseas/patologia , MicroRNAs/genética , Sarcoma de Ewing/patologia , Quinases Associadas a rho/genética , Adolescente , Adulto , Neoplasias Ósseas/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Criança , Pré-Escolar , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Invasividade Neoplásica/genética , Sarcoma de Ewing/genética , Adulto Jovem
3.
Braz. j. med. biol. res ; 53(2): e8962, 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1055495

RESUMO

The aims of this study were to evaluate the intra- and interobserver reproducibility of manual segmentation of bone sarcomas in magnetic resonance imaging (MRI) studies and to compare manual and semiautomatic segmentation methods. This retrospective study included twelve osteosarcoma and eight Ewing sarcoma MRI studies performed prior to any therapeutic intervention. All cases were histopathologically confirmed. Three radiologists used 3D-Slicer software to perform manual segmentation of bone sarcomas in a blinded and independent manner. One radiologist segmented manually and also performed semiautomatic segmentation with the GrowCut tool. Segmentation exercises were timed for comparison. The dice similarity coefficient (DSC) and Hausdorff distance (HD) were used to evaluate similarity between the segmentation results and further statistical analyses were performed to compare DSC, HD, and volumetric results. Manual segmentation was reproducible with intraobserver DSC varying from 0.83 to 0.97 and HD from 3.37 to 28.73 mm. Interobserver DSC of manual segmentation showed variation from 0.73 to 0.97 and HD from 3.93 to 33.40 mm. Semiautomatic segmentation compared to manual segmentation resulted in DSCs of 0.71−0.96 and HDs of 5.38−31.54 mm. Semiautomatic segmentation required significantly less time compared to manual segmentation (P value ≤0.05). Among all situations compared, tumor volumetry did not show significant statistical differences (P value >0.05). We found excellent intra- and interobserver agreement for manual segmentation of osteosarcoma and Ewing sarcoma. There was high similarity between manual and semiautomatic segmentation, with a significant reduction of segmentation time using the semiautomatic method.


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Criança , Adolescente , Adulto , Adulto Jovem , Sarcoma de Ewing/diagnóstico por imagem , Neoplasias Ósseas/diagnóstico por imagem , Osteossarcoma/diagnóstico por imagem , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Estudos Retrospectivos
4.
Pathol Oncol Res ; 25(1): 11-20, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28944406

RESUMO

miRNAs have been identified as key regulators of almost all cellular processes, therefore, their dysregulation is involved with several diseases, including cancer. miRNAs specifically related to the metastastic cascade are called metastamiRs and can be involved with different steps of this process, including loss of adhesion. Osteosarcoma (OS) is the most common primary malignant pediatric bone tumor that often presents metastatic disease at diagnosis; therefore, a deeper study of adhesion-associated miRNAs could shed light on its pathophysiology. Online databases were used to select four miRNAs (miR-139; miR-181b; miR-584; miR-708) predicted or validated to target proteins related to adherent junctions and focal adhesion pathways, and their expression levels and possible associations with clinical features evaluated in primary OS samples. Our results showed downregulation of miR-139-5p and miR-708-5p in OS samples compared to non-neoplastic controls. Moreover, lower expression of miR-708-5p was associated with poor overall survival and higher expression of miR-181b-5p related to worst chemotherapy response (low HUVOS level). Based on these results, we selected miR-139-5p and miR-708-5p for further functional testing. Inducing the expression of miR-139-5p diminished the clonogenic capacity of the HOS cell line, while upregulation of miR-708-5p was related to a lower cellular adhesion. In summary, this work identified new signatures of microRNA dysregulation that may serve as useful prognostic markers in this aggressive pediatric bone tumor.


Assuntos
Junções Aderentes/genética , Biomarcadores Tumorais/genética , Neoplasias Ósseas/secundário , Adesões Focais/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Osteossarcoma/patologia , Adolescente , Adulto , Neoplasias Ósseas/genética , Neoplasias Ósseas/cirurgia , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Masculino , Osteossarcoma/genética , Osteossarcoma/cirurgia , Prognóstico , Taxa de Sobrevida , Adulto Jovem
5.
Bone Joint J ; 99-B(1): 139-144, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28053270

RESUMO

AIMS: Our aim was to describe the mid-term appearances of the repair process of the Achilles tendon after tenotomy in children with a clubfoot treated using the Ponseti method. PATIENTS AND METHODS: A total of 15 children (ten boys, five girls) with idiopathic clubfoot were evaluated at a mean of 6.8 years (5.4 to 8.1) after complete percutaneous division of the Achilles tendon. The contour and subjective thickness of the tendon were recorded, and superficial defects and its strength were assessed clinically. The echogenicity, texture, thickness, peritendinous irregularities and potential for deformation of the tendon were evaluated by ultrasonography. RESULTS: The appearance of the Achilles tendon was slightly abnormal, with more thickening and less conspicuous contours than a normal tendon. Its strength was grossly normal, with no insufficiency of the triceps surae. Ultrasonographic findings revealed a mild fusiform thickening in 12 children (80%). The tissue at the site of the repair had a slightly hypoechoic, fibrillar quality with hyperechoic striation and the anterior contour was irregular and blurred. There was a focal narrowing within the healing tissue in two children. CONCLUSION: This mid-term evaluation of the ability of the Achilles tendon to repair after division suggests a combination of intrinsic and extrinsic mechanisms. There were minor abnormalities which did not appear to affect function. Cite this article: Bone Joint J 2017;99-B:139-44.


Assuntos
Tendão do Calcâneo/cirurgia , Pé Torto Equinovaro/cirurgia , Tenotomia/métodos , Tendão do Calcâneo/diagnóstico por imagem , Pré-Escolar , Pé Torto Equinovaro/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Masculino , Variações Dependentes do Observador , Estudos Prospectivos , Resultado do Tratamento , Ultrassonografia , Cicatrização/fisiologia
6.
Genet Mol Res ; 11(1): 448-54, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22427037

RESUMO

Osteochondroma is a cartilage capped benign tumor developing mainly at the juxta-epiphyseal region of long bones. The rate of malignant transformation, mainly into chondrosarcoma, is estimated to be less than 1-3%. Transformation into osteosarcoma is very rare and has been reported only thirteen times. There is little information on treatment and outcome. We report the case of a secondary osteosarcoma arising in the left tibia of a 23-year-old male, 10 years after the initial diagnosis of osteochondroma and after two partial resections. Malignant transformation occurred at the stalk and not at the cartilage cap, as would normally be expected. Chromosome banding analysis revealed the karyotype: 46,XY, t(3;13)(q21;q34) [2]/46,XY [18]. Records from additional cases will help determine the parameters that define these rare secondary bone lesions.


Assuntos
Osteocondroma/patologia , Osteossarcoma/secundário , Tíbia/patologia , Adulto , Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Neoplasias Ósseas/cirurgia , Bandeamento Cromossômico/métodos , Humanos , Cariótipo , Masculino , Osteocondroma/genética , Osteossarcoma/genética , Osteossarcoma/patologia , Osteossarcoma/cirurgia , Adulto Jovem
7.
Vestn Ross Akad Med Nauk ; (3): 11-5, 2010.
Artigo em Russo | MEDLINE | ID: mdl-20420210

RESUMO

The aim of this work was to evaluate selected parameters of oxidative metabolism in peripheral blood lymphocytes of patients with autoimmune thyroiditis (AIT) at the stages of eu- and hypothyroidism. The lymphocytes were shown to accumulate superoxide anion radical, hydrogen peroxide, and TBA-active products in association with the decrease of major enzymatic activities (superoxide dismutase and catalase). Changes in free radical oxidation and activity of key antioxidative enzymes in AIT patients proved unidirectional.


Assuntos
Catalase/sangue , Leucócitos/metabolismo , Espécies Reativas de Oxigênio/sangue , Superóxido Dismutase/sangue , Tireoidite Autoimune/sangue , Adulto , Idoso , Feminino , Humanos , Peróxido de Hidrogênio/sangue , Peroxidação de Lipídeos , Masculino , Pessoa de Meia-Idade , Nitritos/sangue , Oxirredução , Superóxidos/sangue
8.
Genet Mol Res ; 8(4): 1211-7, 2009 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-19866439

RESUMO

Epithelioid sarcoma is a rare, aggressive soft tissue tumor of unknown histogenesis showing predominantly epithelioid cytomorphology. We conducted a conventional and molecular cytogenetic study of a 27-year-old male with epithelioid sarcoma with angiomatoid features. Cytogenetic analysis of epithelioid sarcoma metaphase spreads by GTG-banding revealed a diploid chromosome complement with structural and numerical aberrations. Comparative genomic hybridization analysis demonstrated the amplification of 3p24-pter, 4p15.2-p16 and 18q23, while chromosome losses involved 3p13-p14, 3q24-q26.1, 9q21, and 11q21. Fluorescence in situ hybridization assessment showed normal hybridization patterns for the C-MYC and CCND1 loci; CCND1 RNA overexpression was detected by real-time polymerase chain reaction analysis. Genetic evaluation of this rare condition may be useful in determining if epithelioid sarcoma is associated with a distinct genetic background.


Assuntos
Aberrações Cromossômicas , Sarcoma/genética , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Humanos , Hibridização in Situ Fluorescente , Masculino , Reação em Cadeia da Polimerase , Sarcoma/tratamento farmacológico
9.
Artigo em Russo | MEDLINE | ID: mdl-16401026

RESUMO

Epidemiological study of endocrine system pathology in north areas of Russia was carried out. Major regional factor in Siberia north areas is higher occurrence of thyroid pathology caused by iodine deficiency in water and food. Prevention of this disease is one of most relevant problems in these areas.


Assuntos
Doenças da Glândula Tireoide/epidemiologia , Adulto , Distribuição por Idade , Exposição Ambiental/efeitos adversos , Feminino , Humanos , Incidência , Iodo/deficiência , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Distribuição por Sexo , Sibéria/epidemiologia , Doenças da Glândula Tireoide/etiologia
10.
Arch Orthop Trauma Surg ; 116(5): 266-70, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9177801

RESUMO

The mechanical stability of proximal femoral osteotomies fixed by the tension band wire technique was studied in flexion-compression and torsion tests. The fixation consisted in crossing the section with two Kirschner wires and with a wire cerclage applied to the tension surface. The study was conducted in three steps. First, cyclinders of wood were cut either transversely or at 30 degrees of inclination in relation to the long axis of the specimen, and fixed with two Kirschner wires and a wire cerclage. We concluded that the inclination of the plane of section significantly increased the stability of fixation. No significant difference was observed when oblique sections were made in the reverse orientation. Second, 30 degrees subtrochanteric varus osteotomies were performed in dog femurs, so that the section plane was transverse in one group and oblique in another, after closing the osteotomy. In both groups the fixation was achieved by two Kirschner wires that crossed the osteotomy and a wire cerclage placed on the lateral cortex (tension surface). We concluded that inclination of the osteotomy plane increased the stability of osteosynthesis in bone specimens, as already seen with the wood pieces. Third, the stability of tension band wire fixation was compared with that provided by the AO/ASIF paediatric angled plate. Varus osteotomies (30 degrees) were created at the subtrochanteric level of paired dog femurs. On one side, the femur was fixed with Kirschner wires and a wire cerclage as described previously. For the other femur, the osteotomy was fixed with the angled plate. We found that both types of fixation presented the same stability in flexion-compression tests. However, under torsion the tension band wire fixation was 30%-50% less stable than the plate fixation.


Assuntos
Fios Ortopédicos , Colo do Fêmur/cirurgia , Animais , Placas Ósseas , Cães , Fraturas do Colo Femoral/cirurgia , Osteotomia/instrumentação , Osteotomia/métodos , Estresse Mecânico , Anormalidade Torcional
11.
J Rheumatol ; 23(4): 646-9, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8730120

RESUMO

OBJECTIVE: To determine whether soluble interleukin 2 receptor (sIL-2R) levels correlate with natural history of disease in patients with systemic sclerosis (SSc). METHODS: The following groups were studied: Group I included 81 consecutive new patients with SSc. Group II consisted of 21 patients with diffuse cutaneous (dc) SSc whose peripheral blood and affected skin had been analyzed for T lymphocyte subsets. Group III contained 38 patients with dcSSc with serial sIL-2R determinations during the course of disease. sIL-2R was performed using a commercial double monoclonal antibody ELISA technique. RESULTS: The 81 Group I patients with SSc had a mean sIL-2R level of 821 units compared with 35 controls, who had a mean of 389 units (p < 0.001). sIL-2R level significantly correlated with the extent of skin thickening (p < 0.005). In Group II patients, sIL-2R was found to correlate with the CD4 to CD8 ratio. Blindly assessed clinical evidence of disease activity from the serial samples of 38 Group III patients was consistent with sIL-2R levels in 83% of the samples. There was high correlation of change in sIL-2R with change in skin score over time in Group III subjects (r = 0.71). CONCLUSIONS: These results suggest a role for T cell activation in the pathogenesis of SSc. sIL-2R levels may be useful adjunct to clinical evaluation in assessing disease activity and predicting future events in patients with SSc.


Assuntos
Receptores de Interleucina-2/metabolismo , Escleroderma Sistêmico/sangue , Idade de Início , Anticorpos Monoclonais , Relação CD4-CD8 , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Ensaio de Imunoadsorção Enzimática , Seguimentos , Humanos , Ativação Linfocitária , Contagem de Linfócitos , Estudos Retrospectivos , Escleroderma Sistêmico/etiologia , Escleroderma Sistêmico/imunologia , Solubilidade , Taxa de Sobrevida
12.
Transplantation ; 33(6): 631-5, 1982 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6179272

RESUMO

Rat-mouse hybridomas have been developed producing monoclonal antibodies which recognize rat major histocompatibility complex specificities. Splenic lymphocytes from a LEW (RT1l) rat alloimmunized against ACI (Rt1a) splenocytes were used for hybridoma production. The six clones presented demonstrate two patterns of alloreactivity against ACI tissues: clone 36.3 produces an antibody which agglutinates ACI RBCs and binds to ACI splenic lymphocytes and RBCs. Five clones, 65.6, 79.7,1, 79.7.5, 155.3.1, and 189.3.5, from four independent wells produce monoclonal antibodies which bind to ACI splenic lymphocytes but not RBCs. Screening of these six monoclonal antibodies against a reference panel of RBCs and lymphocytes from 15 standard, congenic, and recombinant rat strains indicated that the monoclonal antibody 36.3 detects a RTI.Aa product ( a rat major histocompatibility complex (MHC) Class I antigen) and that 65.6, 79.7.1, 79.7.5, 155.3.1, and 189.3.5 are monoclonal antibodies which recognize a RT1.Ba private specificity (Class II or Ia antigens). These reagents are unique as they are rat monoclonal alloantibodies recognizing private Ia specificities of the rat MHC.


Assuntos
Anticorpos Monoclonais/imunologia , Epitopos , Antígenos de Histocompatibilidade/imunologia , Animais , Reações Antígeno-Anticorpo , Fusão Celular , Citometria de Fluxo , Imunofluorescência , Testes de Hemaglutinação , Antígenos de Histocompatibilidade/classificação , Imunodifusão , Masculino , Ratos , Ratos Endogâmicos ACI , Ratos Endogâmicos BN , Ratos Endogâmicos BUF , Ratos Endogâmicos F344 , Ratos Endogâmicos Lew , Ratos Endogâmicos WF , Especificidade da Espécie
13.
Lab Invest ; 40(2): 221-6, 1979 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-431040

RESUMO

A combined biochemical and cytochemical study of catalase was performed on alveolar macrophages lavaged from the lungs of adult male rats. Biochemically, catalase activity was present in both a high-speed granule fraction and in the supernatant. The granule-associated activity exhibited latency. Two methods of cell breakage, sonication and homogenization, yielded similar levels and distributions of catalase activity. Catalase activity in whole cells was identified cytochemically by the alkaline diaminobenzidine method and was localized within membrane-lined cytoplasmic granules similar in size to microperoxisomes and associated with cisternae of smooth endoplasmic reticulum. Localization of the reaction product was inhibited by 0.04 M aminotriazole, by cyanide, and by boiling prior to incubation. The cytochemical reaction continued in the absence of exogenous peroxide, but could be prevented by addition of catalase or pyruvate to the peroxide-free medium. Enzyme activity was also localized within a portion of the membrane-bound granules present in the cell fractions used for the biochemical assays.


Assuntos
Catalase/análise , Grânulos Citoplasmáticos/enzimologia , Macrófagos/enzimologia , Amitrol (Herbicida)/farmacologia , Animais , Catalase/metabolismo , Cianetos/farmacologia , Retículo Endoplasmático/enzimologia , Macrófagos/ultraestrutura , Masculino , Ratos , Frações Subcelulares/enzimologia
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