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1.
J Environ Manage ; 249: 109361, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31480009

RESUMO

Effective management of benthic habitats is important for maintaining heathy and functional aquatic ecosystems. To provide managers with the best possible information, characterizing benthic habitats at the community level is essential; yet, acquiring the data sets needed to achieve this task is resource intensive and, at times, prohibitively expensive. Thus, thoughtful assessments of which data to collect and utilize in benthic habitat characterization studies are needed. Environmental data sets commonly used to characterize benthic habitats include a range of variables from water depth and sediment grain size to seabed features identified by sonar backscatter. The objective of this study was to identify the most useful environmental variables for characterizing infaunal benthic habitats and to determine how to best utilize these variables in analyses (e.g., by comparing continuous vs. categorical explanatory variables). The modeling approach used multivariate regression tree and redundancy analysis along with a critical cross-validation step for model evaluation. Results indicated that models with more than ~7 environmental predictors overfitted the data sets analyzed and that categorizing continuous predictors into categorical ones influenced the proportion of infaunal community variation explained by each model. Habitats identified and characterized on the basis of sonar backscatter explained more of the infaunal community variation than any model that used a combination of other environmental variables (e.g., water depth & sediment grain size) or those constructed using categorical habitat classes from existing classification schemes. We therefore recommend maximizing the potential of sonar-derived variables for characterizing infaunal benthic habitats in nearshore, soft-sediment ecosystems.


Assuntos
Ecossistema , Água
2.
Vet Parasitol ; 216: 72-83, 2016 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-26801598

RESUMO

Reports of resistance to triclabendazole (TCBZ) among fluke populations have increased in recent years. Allied to this, there has been a rise in the prevalence of the disease, which has been linked to climate change. Results from questionnaire surveys conducted in Northern Ireland (NI) in 2005 (covering the years 1999-2004) and 2011 (covering the years 2008-2011) have provided an opportunity to examine the extent to which fluke control practices have changed over a prolonged time-frame, in light of these changes. A number of differences were highlighted. There was a significant shift away from the use of TCBZ over time, with it being replaced largely by closantel. The timing of treatments had moved earlier in the year, perhaps in response to climate change (and an altered pattern of disease). In relation to the frequency of drug treatments, there were no major changes in the overall pattern of drug treatments between the two survey points, although on both occasions approximately one-third of flock owners gave more than 3 treatments per year to ewes. In lowland areas in 2011, flock owners were rotating drug classes more often (each year and at each treatment) than in 2005, whereas in upland areas, flock owners were rotating less often and more were not rotating at all. Between 2005 and 2011, the percentage of flock owners giving quarantine treatments to bought-in stock had halved, to a very low level (approximately 10%). Using data from a complementary TCBZ resistance survey (Hanna et al., 2015), it has been shown that the way in which data are selected and which efficacy formula is applied can influence the calculation of drug efficiency and impact on diagnosis of resistance.


Assuntos
Criação de Animais Domésticos/tendências , Anti-Helmínticos/farmacologia , Benzimidazóis/farmacologia , Fasciolíase/veterinária , Doenças dos Ovinos/prevenção & controle , Criação de Animais Domésticos/métodos , Animais , Anti-Helmínticos/administração & dosagem , Anti-Helmínticos/uso terapêutico , Antígenos de Helmintos/análise , Benzimidazóis/administração & dosagem , Benzimidazóis/uso terapêutico , Mudança Climática , Resistência a Medicamentos , Fasciola/efeitos dos fármacos , Fasciola/isolamento & purificação , Fasciolíase/tratamento farmacológico , Fasciolíase/epidemiologia , Fasciolíase/prevenção & controle , Fezes/química , Fezes/parasitologia , Feminino , Irlanda do Norte/epidemiologia , Contagem de Ovos de Parasitas/veterinária , Prevalência , Estações do Ano , Ovinos , Doenças dos Ovinos/tratamento farmacológico , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/parasitologia , Inquéritos e Questionários , Triclabendazol
3.
Ann Oncol ; 26(2): 407-14, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25421877

RESUMO

BACKGROUND: Four international study groups undertook a large study in resectable osteosarcoma, which included two randomised controlled trials, to determine the effect on survival of changing post-operative chemotherapy based on histological response. PATIENTS AND METHODS: Patients with resectable osteosarcoma aged ≤40 years were treated with the MAP regimen, comprising pre-operatively of two 5-week cycles of cisplatin 120 mg/m(2), doxorubicin 75 mg/m(2), methotrexate 12 g/m(2) × 2 (MAP) and post-operatively two further cycles of MAP and two cycles of just MA. Patients were randomised after surgery. Those with ≥10% viable tumour in the resected specimen received MAP or MAP with ifosfamide and etoposide. Those with <10% viable tumour were allocated to MAP or MAP followed by pegylated interferon. Longitudinal evaluation of quality of life was undertaken. RESULTS: Recruitment was completed to the largest osteosarcoma study to date in 75 months. Commencing March 2005, 2260 patients were registered from 326 centres across 17 countries. About 1334 of 2260 registered patients (59%) were randomised. Pre-operative chemotherapy was completed according to protocol in 94%. Grade 3-4 neutropenia affected 83% of cycles and 59% were complicated by infection. There were three (0.13%) deaths related to pre-operative chemotherapy. At definitive surgery, 50% of patients had at least 90% necrosis in the resected specimen. CONCLUSIONS: New models of collaboration are required to successfully conduct trials to improve outcomes of patients with rare cancers; EURAMOS-1 demonstrates achievability. Considerable regulatory, financial and operational challenges must be overcome to develop similar studies in the future. The trial is registered as NCT00134030 and ISRCTN 67613327.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Osteossarcoma/tratamento farmacológico , Adolescente , Neoplasias Ósseas/cirurgia , Criança , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Terapia Combinada , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Etoposídeo/administração & dosagem , Etoposídeo/efeitos adversos , Feminino , Humanos , Ifosfamida/administração & dosagem , Ifosfamida/efeitos adversos , Interferon-alfa/administração & dosagem , Interferon-alfa/efeitos adversos , Masculino , Metotrexato/administração & dosagem , Metotrexato/efeitos adversos , Terapia Neoadjuvante , Osteossarcoma/cirurgia , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/efeitos adversos , Qualidade de Vida , Projetos de Pesquisa , Adulto Jovem
4.
Virchows Arch ; 463(1): 79-84, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23760783

RESUMO

Although fibrous dysplasia (FD) is a benign fibro-osseous lesion, locally aggressive behaviour has rarely been described but is poorly characterised. In this study, we document clinical, radiological and pathological (including molecular genetics) findings in three cases of locally aggressive FD, two of which involved the ribs. Lesions in these cases, one of which was a recurrent lesion, were followed up for 2-7 years. All of the lesions showed typical histological features of FD but were characterised by extension through the bone cortex into the extra-osseous soft tissue. The lesions did not exhibit overexpression/amplification of CDK4 and MDM2; in two of the cases, a GNAS mutation was identified. Our findings confirm that FD can rarely exhibit locally aggressive behaviour with extension beyond the bone compartment into the surrounding soft tissue; these lesions can be distinguished from low-grade intramedullary osteosarcoma by lack of amplification/overexpression of CDK4 and MDM2 and the presence of a GNAS mutation.


Assuntos
Displasia Fibrosa Óssea/patologia , Adulto , Idoso , Proteínas de Ciclo Celular , Quinase 4 Dependente de Ciclina/análise , Feminino , Displasia Fibrosa Óssea/diagnóstico por imagem , Displasia Fibrosa Óssea/genética , Displasia Fibrosa Óssea/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Nucleares/análise , Proteínas Proto-Oncogênicas/análise , Tomografia Computadorizada por Raios X
5.
Br J Cancer ; 108(4): 964-72, 2013 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-23175151

RESUMO

BACKGROUND: Neurofibromatosis type 1 is one of the most common familial diseases, the hallmark of which is the development of multiple neurofibromas. These are benign nerve sheath tumours, which can transform into malignant peripheral nerve sheath tumours (MPNST). METHODS: The aim of this study was to identify differentially expressed microRNA (miRNA) in neurofibromas and MPNST obtained from patients with neurofibromatosis type 1 using microarray analysis. Differential expression was validated by reverse transcription quantitative-PCR, and functional studies were performed after transfection of miRNA oligonucleotide mimics into MPNST cells. RESULTS: Sixteen miRNA were significantly differentially expressed in MPNST compared with NF, and of these fourteen were downregulated in MPNST: these included miR-30e*, miR-29c*, miR-29c, miR-340*, miR-30c, miR-139-5p, miR-195, miR-151-5p, miR-342-5p, miR-146a, miR-150, miR-223, let-7 a and let-7 g with a false discovery rate of q=8.48E-03 for the least significant miRNA. In contrast, miR-210 and miR-339-5p were upregulated in MPNST compared with neurofibromas. Prediction softwares/algorithms identified a list of genes targeted by miR-29c including extracellular matrix genes and matrix metalloproteinase (MMP)-2, all of which are reported to be involved in cell migration and invasion. Functional studies in a MPNST cell line, sNF96.2, using a mimic of the mature miR-29c showed reduced invasion, whereas there was no change in proliferation. Zymography of the manipulated cells showed that MMP2 activity was also reduced when miR-29c expression was forced in sNF96.2. CONCLUSION: We provide evidence that reduction of miR-29c has a pivotal role in the progression of nerve sheath tumours and results by increasing the invasive/migratory properties of nerve sheath tumours.


Assuntos
Genes Supressores , MicroRNAs , Neoplasias de Bainha Neural/genética , Linhagem Celular Tumoral , Progressão da Doença , Regulação para Baixo , Matriz Extracelular/genética , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Neurofibromatose 1/genética
6.
Vet Parasitol ; 176(1): 34-42, 2011 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-21093156

RESUMO

A sheep trial was performed to standardise a coproantigen reduction test (CRT) protocol for the diagnosis of resistance to triclabendazole (TCBZ) in Fasciola hepatica). The CRT employs the BIO K201 Fasciola coproantigen ELISA (Bio-X Diagnostics, Jemelle, Belgium) to test for the presence of F. hepatica coproantigens in a faecal sample. If it is coproantigen-positive, the CRT protocol recommends that faecal samples are re-tested for coproantigens at 14 days post-treatment (dpt), with negative testing at this point indicating TCBZ success. Initial work aimed to confirm the sensitivity of the BIO K201 ELISA for Fasciola infection and investigate whether coproantigens represent a robust reduction marker of TCBZ efficacy. Thirty-eight, indoor-reared sheep were artificially infected with F. hepatica isolates known to be susceptible (Cullompton) and resistant (Sligo) to TCBZ action, respectively. Treatment was administered at 12 weeks post-infection (wpi), with 2 sheep groups, infected with each isolate, culled at 2 and 4 weeks post-treatment (wpt), respectively. Necropsy was performed to confirm treatment efficacy. Individual faecal samples were collected twice-weekly throughout the trial period. Additional work focused on the effect of temperature on faecal sample collection and storage. Faecal samples collected from sheep positive for F. hepatica infection were sub-sampled and left at room temperature. Individual sub-samples were tested by ELISA on consecutive days and these readings compared to the original test result on the day of collection. In addition, ELISA values were compared between faecal sub-samples prepared on the day of sampling and post storage at -20°C. Also, an immunocytochemical study was performed to determine the tissue site of origin of the coproantigen protein in the fluke. Results showed that the BIO K201 ELISA was sensitive for Fasciola coproantigens, with coproantigens detectable from 5 wpi onwards. The suitability of coproantigens as a diagnostic marker of TCBZ efficacy was supported by the absence and presence of coproantigens in TCBZ-treated Cullompton (TCBZ-susceptible) and Sligo (TCBZ-resistant) F. hepatica infections at 2 and 4 wpt, respectively. Study results suggest that low to moderate temperature has little, if any, impact on coproantigen stability in faecal samples, but that higher temperatures may have. Immunolabelling for the coproantigen showed that it was specific to the gastrodermal cells of both adult and juvenile flukes.


Assuntos
Anti-Helmínticos/farmacologia , Antígenos de Helmintos/análise , Benzimidazóis/farmacologia , Resistência a Medicamentos , Ensaio de Imunoadsorção Enzimática/veterinária , Fasciola hepatica/efeitos dos fármacos , Animais , Fasciolíase/parasitologia , Fasciolíase/veterinária , Fezes/química , Feminino , Masculino , Sensibilidade e Especificidade , Ovinos , Doenças dos Ovinos/tratamento farmacológico , Doenças dos Ovinos/parasitologia , Fatores de Tempo , Triclabendazol
7.
J Bone Joint Surg Br ; 92(2): 262-6, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20130320

RESUMO

Elastofibroma dorsi is an uncommon, benign, slow-growing soft-tissue tumour of uncertain aetiology. It classically presents as an ill-defined mass at the inferior pole of the scapula with symptoms which include swelling, discomfort, snapping, stiffness and occasionally pain. We report the symptoms, function and outcome after treatment of 21 elastofibromas in 15 patients. All were diagnosed by MRI and early in the series four also underwent CT-guided biopsy to confirm the diagnosis. In all, 18 tumours were excised and three were observed. After excision, the mean visual analogue score for pain decreased from 4.6 (0 to 10) pre-operatively to 2.4 (0 to 8) post-operatively (p = 0.04). The mean shoulder function, at a mean follow-up of 4.2 years (3 months to 16 years), was 78.1% (30 to 100) using the Stanmore percentage of normal shoulder assessment scoring system. The mean range of forward flexion improved from 135 degrees (70 degrees to 180 degrees ) to 166 degrees (100 degrees to 180 degrees ) after excision (p = 0.005). In four patients a post-operative haematoma formed; one required evacuation. Three patients developed a post-operative seroma requiring needle aspiration and one developed a superficial infection which was treated with antibiotics. Our findings support previous reports suggesting that a pre-operative tissue diagnosis is not necessary in most cases since the lesion can be confidently diagnosed by MRI, when interpreted in the light of appropriate clinical findings. Surgical excision in symptomatic patients, is helpful. It has been suggested that elastofibroma is caused by a local tissue reaction and is not a true neoplastic process. A strong association has been noted between elastofibroma and repetitive use of the shoulder, which is supported by our findings.


Assuntos
Fibroma/diagnóstico , Neoplasias de Tecidos Moles/diagnóstico , Adulto , Idoso , Feminino , Fibroma/cirurgia , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Amplitude de Movimento Articular , Escápula , Articulação do Ombro/fisiopatologia , Neoplasias de Tecidos Moles/cirurgia , Tomografia Computadorizada por Raios X , Resultado do Tratamento
8.
J Bone Joint Surg Br ; 91(6): 815-9, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19483239

RESUMO

We report a case which highlights the progression of osteofibrous dysplasia to adamantinoma and questions whether intralesional curettage is the appropriate treatment. The role of a joint-sparing massive endoprosthesis using cortical fixation is demonstrated and we describe a unique biomedical design which resulted in the manufacture of an end cap to allow amputation through a custom-made proximal tibial replacement, rather than an above-knee amputation following recurrence.


Assuntos
Adamantinoma/cirurgia , Amputação Cirúrgica/métodos , Doenças do Desenvolvimento Ósseo/cirurgia , Neoplasias Ósseas/cirurgia , Recidiva Local de Neoplasia/cirurgia , Adamantinoma/patologia , Adulto , Doenças do Desenvolvimento Ósseo/patologia , Neoplasias Ósseas/patologia , Diagnóstico Diferencial , Progressão da Doença , Feminino , Humanos , Recidiva Local de Neoplasia/patologia , Dor/cirurgia , Esqui/lesões , Fraturas da Tíbia/complicações
9.
Br J Cancer ; 100(9): 1406-14, 2009 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-19401700

RESUMO

Chordomas are radio- and chemo-resistant tumours and metastasise in as many as 40% of patients. The aim of this study was to identify potential molecular targets for the treatment of chordoma. In view of the reported association of chordoma and tuberous sclerosis complex syndrome, and the available therapeutic agents against molecules in the PI3K/AKT/TSC1/TSC2/mTOR pathway, a tissue microarray of 50 chordoma cases was analysed for expression of active molecules involved in this signalling pathway by immunohistochemistry and a selected number by western blot analysis. Chordomas were positive for p-AKT (92%), p-TSC2 (96%), p-mTOR (27%), total mTOR (75%), p-p70S6K (62%), p-RPS6 (22%), p-4E-BP1 (96%) and eIF-4E (98%). Phosphatase and tensin homologue deleted on chromosome 10 expression was lost in 16% of cases. Mutations failed to be identified in PI3KCA and RHEB1 in the 23 cases for which genomic DNA was available. Fluorescence in situ hybridisation analysis for mTOR and RPS6 loci showed that 11 of 33 and 21 of 44 tumours had loss of one copy of the respective genes, results which correlated with the loss of the relevant total proteins. Fluorescence in situ hybridisation analysis for loci containing TSC1 and TSC2 revealed that all cases analysed harboured two copies of the respective genes. On the basis of p-mTOR and or p-p70S6K expression there is evidence indicating that 65% of the chordomas studied may be responsive to mTOR inhibitors, rapamycin or its analogues, and that patients may benefit from combined therapy including drugs that inhibit AKT.


Assuntos
Cordoma/genética , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt/genética , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Western Blotting , Cordoma/patologia , Feminino , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina , Pessoa de Meia-Idade , Complexos Multiproteicos , Análise de Sequência com Séries de Oligonucleotídeos , Fosfatidilinositol 3-Quinases/metabolismo , Análise Serial de Proteínas , Proteínas , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR , Fatores de Transcrição/metabolismo , Esclerose Tuberosa/tratamento farmacológico , Esclerose Tuberosa/genética , Esclerose Tuberosa/patologia , Proteína 1 do Complexo Esclerose Tuberosa , Proteína 2 do Complexo Esclerose Tuberosa , Proteínas Supressoras de Tumor/metabolismo , Adulto Jovem
10.
Cell Death Differ ; 15(6): 1063-72, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18404156

RESUMO

Here we investigate the function of zebrafish Bcl-2 family proteins and demonstrate important conservation of function across zebrafish and mammalian systems. We have isolated a zebrafish ortholog of mammalian BIM and show that it is the most toxic of the zebrafish BH3-only genes examined, sharing this characteristic with the mammalian BIM gene. The zebrafish bad gene shows a complete lack of embryonic lethality, but like mammalian BAD, its pro-apoptotic activity is regulated through phosphorylation of critical serines. We also found that the pattern of mitochondrial dysfunction observed by zebrafish BH3 domain peptides in a mammalian cytochrome c release assay recapitulates the pattern of embryonic lethality induced by the respective mRNA injections in vivo. In contrast to zebrafish Bim, Bid exhibited only weak binding to zebrafish Bcl-2 and moderate-to-weak overall lethality in zebrafish embryos and isolated mitochondria. Given that zebrafish Bcl-2 binds strongly to mammalian BID and BIM peptides and proteins, the protein identified as the zebrafish Bid ortholog has different properties than mammalian BID. Overall, our results demonstrate the high degree of functional conservation between zebrafish and mammalian Bcl-2 family proteins, thus validating the zebrafish as a model system to further dissect the molecular mechanisms that regulate apoptosis in future forward genetic and chemical modifier screens.


Assuntos
Proteínas Reguladoras de Apoptose/fisiologia , Proteínas de Membrana/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Proteínas Proto-Oncogênicas/fisiologia , Proteínas de Peixe-Zebra/fisiologia , Sequência de Aminoácidos , Animais , Apoptose , Proteínas Reguladoras de Apoptose/química , Proteínas Reguladoras de Apoptose/genética , Proteína 11 Semelhante a Bcl-2 , Linhagem Celular , Sistema Nervoso Central/efeitos da radiação , Humanos , Proteínas de Membrana/química , Proteínas de Membrana/genética , Camundongos , Mitocôndrias/metabolismo , Dados de Sequência Molecular , Mutação , Domínios e Motivos de Interação entre Proteínas , Proteínas Proto-Oncogênicas/química , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-bcl-2/química , Tolerância a Radiação , Homologia de Sequência de Aminoácidos , Serina/genética , Peixe-Zebra/embriologia , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/química , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , Proteína de Morte Celular Associada a bcl/química , Proteína de Morte Celular Associada a bcl/metabolismo
11.
Cell Death Differ ; 15(3): 580-8, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18084238

RESUMO

The Epstein-Barr and Kaposi's sarcoma gamma-herpesviruses (KSHVs) are associated with certain cancers, and encode B-cell leukemia/lymphoma 2 (BCL-2) homologs, BHRF-1 and KSHV BCL-2, respectively. Little is known, however, about the molecular interactions allowing viral BCL-2 homologs to mediate their anti-apoptotic function. Cellular anti-apoptotic proteins, such as BCL-2 and MCL-1, prevent death via selective interactions with pro-death BH3-only proteins. To investigate whether BHRF-1 and KSHV BCL-2 function similarly, we made recombinant BHRF-1 and KSHV BCL-2 proteins. We identified the individual binding patterns for BHRF-1 and KSHV BCL-2 to BH3 domains. These studies surprisingly showed that KSHV BCL-2 is more closely related to MCL-1 than to BCL-2, a result confirmed by sequence analysis. GST-BHRF-1 and GST-KSHV BCL-2 bound BH3-only family proteins from human cells. BHRF-1 protected mammalian cells from growth factor withdrawal, etoposide and adriamycin. We found that both BCL-2 and BHRF-1 sequestered pro-death BH3-only proteins under growth factor-deficient conditions. Finally, we tested the ability of a panel of BH3 peptides to inhibit BHRF-1 and KSHV BCL-2 function in a mitochondrial model of apoptosis. We found that each could be inhibited by the select group of BH3 peptides identified in our binding assay. Our studies define the biochemical interactions underlying BHRF-1 and KSHV BCL-2 anti-apoptotic function, and identify peptides that are prototypic inhibitors of this function.


Assuntos
Proteínas Oncogênicas/antagonistas & inibidores , Proteínas Oncogênicas/química , Proteínas Proto-Oncogênicas c-bcl-2/química , Proteínas Virais/antagonistas & inibidores , Proteínas Virais/química , Sequência de Aminoácidos , Apoptose , Proteínas Reguladoras de Apoptose/metabolismo , Proteína 11 Semelhante a Bcl-2 , Linhagem Celular , Dano ao DNA , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Proteínas de Membrana/metabolismo , Dados de Sequência Molecular , Proteínas Oncogênicas/metabolismo , Peptídeos/química , Peptídeos/metabolismo , Domínios e Motivos de Interação entre Proteínas , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Virais/metabolismo
12.
J Bone Joint Surg Br ; 89(11): 1504-8, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17998190

RESUMO

Four patients who developed malignant synovial tumours are described; one with chondromatosis developed a synovial chondrosarcoma and three with pigmented villonodular synovitis developed malignant change. The relevant literature is discussed.


Assuntos
Condromatose Sinovial/etiologia , Membrana Sinovial/metabolismo , Sinovite Pigmentada Vilonodular/etiologia , Idoso , Idoso de 80 Anos ou mais , Neoplasias Ósseas/patologia , Transformação Celular Neoplásica/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Membrana Sinovial/patologia , Resultado do Tratamento
15.
Histopathology ; 50(6): 691-704, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17493233

RESUMO

AIMS: To report on the mutation-specific restriction enzyme digest (MSRED) method using paraffin-embedded tissue as a means of detecting GNAS1 mutations in fibrous dysplasia (FD), and to determine if any of the reported GNAS1 mutations in endocrine neoplasms, not previously documented in FD, can be found in FD. METHODS AND RESULTS: Sixty-seven cases of extragnathic FD were analysed as two groups, 1997-2002 and 2003-06, chosen because tissue fixation and decalcification methods were more accurately recorded in the latter. MSRED revealed that between 2003 and 2006, 93% of 28 'in house' extragnathic cases harboured a GNAS1 mutation, compared with 75% of 32 cases before 2003. Fixation times of no more than 48 h and decalcification in ethylenediamine tetraacetic acid gave the best results. Of the 56 mutations detected (five gnathic, 51 extragnathic), 32 (57%) were R201H, 21 (38%) were R201C and three (5%) were Q227L. Two Q227L extragnathic cases had unusual clinical/radiological findings. No mutations were detected in osteofibrous dysplasia. CONCLUSION: Detection of GNAS1 mutations by MSRED is a valuable adjunct to the histopathological diagnosis of FD. This is the first report of a Q227L mutation in FD, although it has been previously documented in pituitary adenoma.


Assuntos
Códon/genética , Displasia Fibrosa Óssea/genética , Subunidades alfa Gs de Proteínas de Ligação ao GTP/genética , Testes Genéticos/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/metabolismo , Osso e Ossos/patologia , Criança , Pré-Escolar , Cromograninas , Análise Custo-Benefício , Análise Mutacional de DNA , Feminino , Displasia Fibrosa Óssea/metabolismo , Subunidades alfa Gs de Proteínas de Ligação ao GTP/metabolismo , Regulação da Expressão Gênica , Testes Genéticos/economia , Humanos , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Radiografia , Mapeamento por Restrição/métodos , Sensibilidade e Especificidade
16.
Cell Prolif ; 40(2): 185-95, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17472726

RESUMO

INTRODUCTION: Human mesenchymal stem cell (hMSC) proliferation and development is regulated by many signalling pathways. gamma-Secretases play an important role in Notch signalling as well as other processes that are involved in developmental decisions, but their role in hMSC proliferation and cell fate decisions has not been explored. OBJECTIVE: To investigate the role of gamma-secretases in hMSC proliferation and differentiation. MATERIALS AND METHODS: Using the gamma-secretase inhibitor N-[N-(3,5-Difluorophenacetyl-L-alanyl]-S-phenylglycine t-butyl ester (DAPT), we investigated their role in hMSC growth and differentiation to chondrogenic, osteogenic and adipogenic fates. RESULTS: We found that inhibiting gamma-secretases reduced the rate of hMSC proliferation, and altered hMSC differentiation in vitro. Addition of DAPT had an inhibitory effect on chondrogenesis resulting in impaired cartilage matrix production and altered chondrocyte morphology. DAPT treated chrodrocytic pellets had reduced levels of Hes1 and Hey1 suggesting that these effects are mediated via Notch signalling. Addition of the DAPT inhibitor to osteogenic cultures did not alter the appearance of bone markers, however, adipogenesis occurred in these cultures in a DAPT concentration-dependent manner. DAPT did not enhance adipogenesis in the presence of a potent adipogenic cocktail, but had an adipogenic effect when combined with dexamethasone only. CONCLUSION: We conclude that gamma-secretases play an important role in both hMSC proliferation and differentiation.


Assuntos
Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Diferenciação Celular/efeitos dos fármacos , Dipeptídeos/farmacologia , Inibidores Enzimáticos/farmacologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Adulto , Secretases da Proteína Precursora do Amiloide/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Proliferação de Células/efeitos dos fármacos , Condrogênese/efeitos dos fármacos , Dexametasona/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Células-Tronco Mesenquimais/enzimologia , Osteogênese/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Frações Subcelulares , Fatores de Transcrição HES-1
17.
Eur J Pediatr ; 166(9): 905-9, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17120035

RESUMO

We report on a child who presented clinical manifestations of both neurofibromatosis type 1 (NF1) and cherubism. With genetic testing, we found a mutation in the NF-1 gene, confirming the neurocutaneous disorder. Histology when correlated with radiological evaluation of a mandibular biopsy was consistent with cherubism. This is the first report in the literature of a child with proven neurofibromatosis type 1 and cherubism without extragnathic lesions. This emphasises that cherubism is a clinical phenotype that can be associated with a number of germline mutations involving SH3BP2, PTPN11 and NF1.


Assuntos
Querubismo/complicações , Genes da Neurofibromatose 1 , Neurofibromatose 1/complicações , Adolescente , Sequência de Bases , Querubismo/diagnóstico por imagem , Querubismo/patologia , Criança , Humanos , Masculino , Mutação , Neurofibromatose 1/diagnóstico , Neurofibromatose 1/genética , Fenótipo , Radiografia
18.
J Pathol ; 209(2): 157-65, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16538613

RESUMO

Chordomas are malignant tumours that occur along the spine and are thought to derive from notochordal remnants. There is significant morphological variability between and within chordomas, with some showing prominent areas of chondroid differentiation. Our microarray data from a broad range of connective tissue neoplasms indicate that, at the transcriptional level, chordomas resemble cartilaginous neoplasms. Here we show that chordomas express many genes known to be involved in cartilage development, but they also uniquely express genes distinguishing them from chondroid neoplasms. The brachyury transcription factor, known to be involved in notochordal development, is only expressed by chordomas. Using a polyclonal antibody, we show that brachyury is expressed in the embryonic notochord and in all 53 chordomas analysed, labelling both chondroid and chordoid areas of these tumours. In contrast, the protein was not detected in over 300 neoplasms, including 163 chondroid tumours. Brachyury was not detected in the nucleus pulposus, arguing against the hypothesis that this tissue derives directly from the notochord. These data provide compelling evidence that chordomas derive from notochord and demonstrate that brachyury is a specific marker for the notochord and notochord-derived tumours.


Assuntos
Biomarcadores Tumorais/análise , Cordoma/genética , Proteínas Fetais/análise , Notocorda/embriologia , Neoplasias da Coluna Vertebral/genética , Proteínas com Domínio T/análise , Biomarcadores Tumorais/genética , Doenças das Cartilagens/diagnóstico , Doenças das Cartilagens/genética , Condrossarcoma/diagnóstico , Condrossarcoma/embriologia , Condrossarcoma/genética , Cordoma/diagnóstico , Cordoma/embriologia , Proteínas Fetais/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Imuno-Histoquímica/métodos , Queratinas/análise , Queratinas/genética , Notocorda/química , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Neoplasias da Coluna Vertebral/diagnóstico , Neoplasias da Coluna Vertebral/embriologia , Proteínas com Domínio T/genética , Distribuição Tecidual
19.
J Bone Joint Surg Br ; 88(2): 203-5, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16434524

RESUMO

We prospectively studied the clinical, arthroscopic and histological results of collagen-covered autologous chondrocyte implantation (ACI-C) in patients with symptomatic osteochondritis dissecans of the knee. The study included 37 patients who were evaluated at a mean follow-up of 4.08 years. Clinical results showed a mean improvement in the modified Cincinnati score from 46.1 to 68.4. Excellent and good clinical results were seen in 82.1% of those with juvenile-onset osteochondritis dissecans but in only 44.4% of those with adult-onset disease. Arthroscopy at one year revealed International Cartilage Repair Society grades of 1 or 2 in 21 of 24 patients (87.5%). Of 23 biopsies, 11 (47.8%) showed either a hyaline-like or a mixture of hyaline-like and fibrocartilage, 12 (52.2%) showed fibrocartilage. The age at the time of ACI-C determined the clinical outcome for juvenile-onset disease (p = 0.05), whereas the size of the defect was the major determinant of outcome in adult-onset disease (p = 0.01).


Assuntos
Condrócitos/transplante , Colágeno/uso terapêutico , Articulação do Joelho/cirurgia , Osteocondrite Dissecante/cirurgia , Adolescente , Adulto , Idade de Início , Envelhecimento/fisiologia , Análise de Variância , Artroscopia/métodos , Cartilagem Articular/patologia , Cartilagem Articular/cirurgia , Criança , Humanos , Articulação do Joelho/patologia , Osteocondrite Dissecante/patologia , Complicações Pós-Operatórias , Estudos Prospectivos , Transplante Autólogo , Resultado do Tratamento
20.
Skeletal Radiol ; 35(4): 233-9, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16220269

RESUMO

Synovial sarcoma (SS) arises in soft tissues but may invade adjacent bone. We describe a case of SS presenting as aggressive lysis of the proximal ulna, the imaging of which suggested a primary bone lesion. Needle biopsy showed a "small round blue cell tumour", and a primitive neuroectodermal tumour (PNET)/Ewing sarcoma was suggested on the basis of the imaging appearances. The definitive diagnosis of synovial sarcoma was made following molecular genetic studies, which demonstrated a fusion product incorporating the genes SYT and SSX1. The importance of correct diagnosis to guide appropriate management, and, therefore, the necessity for molecular genetic studies, is discussed.


Assuntos
Neoplasias Ósseas/diagnóstico , Tumores Neuroectodérmicos Primitivos/diagnóstico , Sarcoma Sinovial/diagnóstico , Ulna , Adulto , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/genética , Diagnóstico Diferencial , Articulação do Cotovelo/diagnóstico por imagem , Articulação do Cotovelo/patologia , Humanos , Masculino , Proteínas de Neoplasias/genética , Tumores Neuroectodérmicos Primitivos/diagnóstico por imagem , Tumores Neuroectodérmicos Primitivos/genética , Proteínas Proto-Oncogênicas/genética , Radiografia , Proteínas Repressoras/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sarcoma Sinovial/diagnóstico por imagem , Sarcoma Sinovial/genética , Ulna/diagnóstico por imagem , Ulna/patologia
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