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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.
Ann Oncol ; 28(6): 1230-1242, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28184416

RESUMO

Chordomas are rare, malignant bone tumors of the skull-base and axial skeleton. Until recently, there was no consensus among experts regarding appropriate clinical management of chordoma, resulting in inconsistent care and suboptimal outcomes for many patients. To address this shortcoming, the European Society of Medical Oncology (ESMO) and the Chordoma Foundation, the global chordoma patient advocacy group, convened a multi-disciplinary group of chordoma specialists to define by consensus evidence-based best practices for the optimal approach to chordoma. In January 2015, the first recommendations of this group were published, covering the management of primary and metastatic chordomas. Additional evidence and further discussion were needed to develop recommendations about the management of local-regional failures. Thus, ESMO and CF convened a second consensus group meeting in November 2015 to address the treatment of locally relapsed chordoma. This meeting involved over 60 specialists from Europe, the United States and Japan with expertise in treatment of patients with chordoma. The consensus achieved during that meeting is the subject of the present publication and complements the recommendations of the first position paper.


Assuntos
Cordoma/terapia , Guias de Prática Clínica como Assunto , Humanos , Recidiva Local de Neoplasia
3.
J Wound Care ; 25(5): 256-65, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27169341

RESUMO

OBJECTIVE: To evaluate the performance and safety of Mepilex Transfer Ag (MTAg) in the treatment of infected diabetic foot ulcers (DFU). METHOD: Patients with locally infected DFU were treated with the test dressing for up to 4 weeks, with a further 12 weeks of follow-up in a non-comparative study. Changes to wound infection and wound size as well as the condition of the peri-wound skin from baseline were assessed. Wound pain during dressing change was measured using a visual analogue scale (VAS). The investigators and patients documented their opinions on their overall experience of the test dressing and on key performance parameters. RESULTS: Following treatment with the test dressing, the signs and symptoms of local wound infection present in the target DFU were substantially reduced compared with baseline. Following the posttreatment evaluation, the majority of the DFU exhibited no signs of infection. and mean wound size was reduced by 50%. Wound size also continued to steadily decrease during follow-up. At the end of treatment five DFUs were completely healed and a further six healed by the end of the follow-up period. Concomitantly, over the course of the study, wound exudate levels were reduced and there was a significant improvement in the condition of the peri-wound area. Wound pain at dressing change was low throughout; generally patients felt no anxiety during the dressing change procedure. The patients considered it a comfortable dressing that remained in place and allowed ease of movement during wear. The investigating clinicians were highly satisfied with the overall performance, especially with respect to its ease of application and removal, conformability and flexibility. CONCLUSION: This study has demonstrated the potential of the dressing to provide topical antimicrobial activity directly to an infected DFU, suggesting prompt treatment of an infected DFU with this topical antimicrobial could aid wound complications. DECLARATION OF INTEREST: The authors have no conflict of interest to declare.


Assuntos
Anti-Infecciosos Locais/uso terapêutico , Bandagens , Pé Diabético/terapia , Silicones , Compostos de Prata/uso terapêutico , Infecção dos Ferimentos/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Exsudatos e Transudatos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Satisfação do Paciente , Estudos Prospectivos
4.
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
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.
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
7.
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
8.
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
9.
Parasitology ; 136(6): 665-80, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19368745

RESUMO

Sheep infected with the triclabendazole-susceptible, Cullompton isolate of Fasciola hepatica were dosed with 15 mg/kg of compound alpha at 12 weeks post-infection. Adult flukes were recovered from the bile ducts at 24, 48 and 72 h post-treatment (p.t.). Ultrastructural changes to the flukes were assessed using transmission electron microscopy (TEM), with a view to gathering information on the mechanism(s) of action for compound alpha and on the possible route of its entry into F. hepatica. The tegumental syncytium was more severely affected than the gut at all time-points p.t. with compound alpha, suggesting a predominantly trans-tegumental route of uptake. Disruption to the tegumental system became increasingly severe over time. A stress response was observed at 24 h p.t. and took the form of blebbing and increases in the production and transport of secretory bodies. By 72 h p.t., extensive tegumental loss and degeneration of the tegumental cell bodies had occurred. Degeneration of subtegumental tissues and internal flooding were also observed. Changes in the gastrodermal cells were slow to develop: reduced secretory activity was evident at 72 h p.t.. There was progressive disruption to the somatic muscle layers, with disorganization of the muscle blocks and loss of muscle fibres.


Assuntos
Anti-Helmínticos/farmacologia , Fasciola hepatica/efeitos dos fármacos , Fasciola hepatica/ultraestrutura , Fasciolíase/veterinária , Imidazóis/farmacologia , Naftalenos/farmacologia , Doenças dos Ovinos/parasitologia , Animais , Fasciolíase/parasitologia , Feminino , Masculino , Microscopia Eletrônica de Transmissão , Ovinos , Fatores de Tempo
10.
Vet Parasitol ; 162(1-2): 75-88, 2009 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-19282108

RESUMO

Seventy indoor-reared sheep were divided into 10 groups to test the efficacy of the experimental fasciolicide, compound alpha (15mg/kg) against triclabendazole (TCBZ)-resistant and TCBZ-susceptible F. hepatica infections. Activity against the Sligo TCBZ-resistant isolate was tested at three time points post-infection (p.i.): 3 days, 4 weeks and 12 weeks (Groups 1-3, respectively). A parallel trial was carried out using TCBZ (10mg/kg) (Groups 5-7): this provided a direct comparison between the efficacies of the two drugs. Group 4 served as an untreated Sligo control. Groups 8 and 9 were setup to test the efficacy of TCBZ and compound alpha against 12-week-old and 4-week-old TCBZ-susceptible, Cullompton infections, respectively. Group 10 served as an untreated Cullompton control. Sheep were sacrificed at 16 weeks p.i. and efficacies were determined. All remaining flukes were collected and measured, before being processed for whole-mount staining to assess the condition of their reproductive structures (testis, vitellaria, ovary and uterus). A second study was carried out to test the activity of compound alpha (15mg/kg) against mature 12-week-old TCBZ-susceptible F. hepatica infections in sheep. Eighteen sheep were divided into two groups, A and B. Group A was treated and Group B served as an untreated control group. Efficacy was determined by reduction in faecal egg counts. The results showed that, whilst compound alpha was very active against adult TCBZ-susceptible flukes, producing a 100% reduction in faecal egg counts, it only caused a 62.5% reduction in fluke burden against juvenile flukes. Moreover, compound alpha was not effective against any stage of infection with TCBZ-resistant F. hepatica in sheep. Data from the trial also revealed biological differences between the two isolates. Thus, Sligo flukes were smaller in size and produced fewer eggs than the Cullompton flukes and their cysts were less infective to sheep. However, they reached the bile ducts more quickly and their eggs appeared in the faeces >2 weeks earlier.


Assuntos
Anti-Helmínticos/farmacologia , Benzimidazóis/farmacologia , Fasciola hepatica/efeitos dos fármacos , Fasciolíase/veterinária , Imidazóis/farmacologia , Naftalenos/farmacologia , Doenças dos Ovinos/tratamento farmacológico , Animais , Fasciolíase/tratamento farmacológico , Fasciolíase/parasitologia , Feminino , Masculino , Ovinos , Doenças dos Ovinos/parasitologia , Triclabendazol
11.
Parasitol Res ; 105(3): 757-67, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19458965

RESUMO

Sheep infected with the triclabendazole-susceptible Cullompton isolate of Fasciola hepatica were dosed with 15 mg/kg of compound alpha at 12 weeks postinfection. Adult flukes were recovered from the bile ducts at 24, 48, and 72 h post-treatment (p.t.). Changes to the surface morphology of the flukes were assessed using scanning electron microscopy (SEM). Flukes were still active at 24 h p.t. and displayed limited areas of disruption, which were restricted to the oral cone region. At 48 h p.t., a reduced level of motility was observed in approximately 50% of the flukes recovered. Swelling of the tegument was more widespread and was accompanied by blebbing and partial loss of the tegumental covering of the spines. By 72 h p.t., the reduction in motility was greater, and approximately one quarter of the flukes recovered were inactive. In the majority of the flukes examined, the midbody region was marked by a discoloration of the flukes' tissues. This was seen to be due to the loss of the tegumental syncytium. Sloughing extended into the tail region in some specimens and, in the more badly-affected specimens, the basal lamina was breached to expose the underlying musculature. Elsewhere on the body, the tegument that remained was relatively normal, although areas of swelling and blebbing were present. Overall, the results provided information on the time-scale of changes to the surface morphology of the fluke that underpin the efficacy of compound alpha.


Assuntos
Antiplatelmínticos/uso terapêutico , Fasciola hepatica/efeitos dos fármacos , Fasciola hepatica/ultraestrutura , Fasciolíase/veterinária , Doenças dos Ovinos/tratamento farmacológico , Animais , Ductos Biliares/parasitologia , Fasciola hepatica/isolamento & purificação , Fasciolíase/tratamento farmacológico , Feminino , Masculino , Microscopia Eletrônica de Varredura/métodos , Ovinos , Doenças dos Ovinos/parasitologia , Fatores de Tempo
12.
Vet Parasitol ; 153(1-2): 52-64, 2008 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-18359570

RESUMO

Eight indoor-reared, crossbred sheep with no pre-exposure to Fasciola hepatica were infected, by oral gavage, with 200 metacercarial cysts of the triclabendazole-susceptible, Cullompton isolate of F. hepatica. Anthelmintic dosing occurred at 4 weeks post-infection using 15mg/kg compound alpha. Two treated sheep per time period were euthanized at 24h, 48h and 72h post-treatment with compound alpha. The two sheep from the control group were euthanized alongside the 24h alpha-treated sheep. Juvenile flukes were recovered from each of the sheeps' liver and processed for examination by electron microscopy. The surface morphology of the flukes' tegument was assessed using scanning electron microscopy (SEM). The ultrastructure of the tegumental syncytium and underlying tegumental cells and connections and somatic musculature were investigated using transmission electron microscopy (TEM). Both the SEM and TEM results revealed a level of disruption that increased with time, culminating at 72h with extensive tegumental loss and substantial degeneration of the cell bodies. The effects of compound alpha on the surface morphology were not particularly apparent until 48h post-treatment, when disruption included swelling and blebbing of the tegument. At 72h post-treatment, SEM revealed loss of the entire syncytial layer over large areas of the flukes. In the areas where the syncytium was lost and the basal lamina exposed, lesions of varying sizes had developed, revealing underlying tissues. Though minor forms of disruption to the ultrastructure of the syncytium were observed using TEM 24h post-treatment, it was at 48h post-treatment that substantial stress responses occurred. They included the presence of autophagic vacuoles and 'open' bodies at the apex of the syncytium and swelling of the basal infolds. The mitochondria within the syncytium and tegumental cells became progressively more disrupted over the three time periods and, by 72h post-treatment, they were frequently distorted and swollen in appearance, and contained severely swollen cristae. By 72h, the number of secretory bodies, particularly T1 bodies, had become significantly depleted in their respective cell bodies, cytoplasmic processes and in the tegumental syncytium. Both the circular and longitudinal muscle bundles were severely disrupted 72h post-treatment. They frequently contained a reduced number of muscle fibres and, in more severe instances, there was an absence of fibres altogether.


Assuntos
Anti-Helmínticos/farmacologia , Fasciola hepatica/efeitos dos fármacos , Fasciolíase/veterinária , Imidazóis/uso terapêutico , Naftalenos/uso terapêutico , Doenças dos Ovinos/tratamento farmacológico , Animais , Fasciola hepatica/ultraestrutura , Fasciolíase/tratamento farmacológico , Fasciolíase/parasitologia , Gastroenteropatias/tratamento farmacológico , Gastroenteropatias/parasitologia , Gastroenteropatias/veterinária , Tegumento Comum , Ovinos , Doenças dos Ovinos/parasitologia
13.
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
14.
Virchows Arch ; 451(5): 871-5, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17674036

RESUMO

Oncogenic osteomalacia (OO) is an acquired form of hypophosphataemic osteomalacia, which is associated most commonly with the development of a benign phosphaturic mesenchymal tumour mixed connective tissue type (PMTMCT). PMTMCTs are generally well vascularised tumours, and many have in the past been classified as haemangiomas and haemangiopericytomas. Although these tumours show some morphological variation, it has been proposed that they represent a distinct histopathological entity. Our aim in this study was to determine by immunohistochemistry the vascular profile of PMTMCT. Using monoclonal antibodies directed against several vascular markers, including the lymphatic endothelial cell antigens LYVE 1 and podoplanin, we found that PMTMCTs, in contrast to haemangiomas and haemangiopericytomas, contain lymphatic vessels. Taken with previous observations that PMTMCTs overexpress FGF23 and other gene products, this finding provides further evidence that most osteomalacia associated mesenchymal tumours represent a discrete pathological entity.


Assuntos
Neoplasias Ósseas/patologia , Vasos Linfáticos/patologia , Mesenquimoma/patologia , Osteomalacia/patologia , Feminino , Fator de Crescimento de Fibroblastos 23 , Fatores de Crescimento de Fibroblastos/análise , Humanos , Masculino , Glicoproteínas de Membrana/análise , Pessoa de Meia-Idade , Fosfatos/urina
15.
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
16.
J Bone Joint Surg Br ; 88(1): 61-4, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16365122

RESUMO

We investigated the prognostic indicators for collagen-covered autologous chondrocyte implantation (ACI-C) performed for symptomatic osteochondral defects of the knee. We analysed prospectively 199 patients for up to four years after surgery using the modified Cincinnati score. Arthroscopic assessment and biopsy of the neocartilage was also performed whenever possible. The favourable factors for ACI-C include younger patients with higher pre-operative modified Cincinnati scores, a less than two-year history of symptoms, a single defect, a defect on the trochlea or lateral femoral condyle and patients with fewer than two previous procedures on the index knee. Revision ACI-C in patients with previous ACI and mosaicplasties which had failed produced significantly inferior clinical results. Gender (p = 0.20) and the size of the defect (p = 0.97) did not significantly influence the outcome.


Assuntos
Cartilagem Articular/transplante , Condrócitos/transplante , Articulação do Joelho/cirurgia , Adolescente , Adulto , Fatores Etários , Artroscopia , Criança , Condromalacia da Patela/cirurgia , Feminino , Humanos , Traumatismos do Joelho/cirurgia , Masculino , Pessoa de Meia-Idade , Osteocondrite Dissecante/cirurgia , Seleção de Pacientes , Prognóstico , Estudos Prospectivos , Índice de Gravidade de Doença , Resultado do Tratamento
17.
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
18.
Knee ; 13(3): 203-10, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16644224

RESUMO

INTRODUCTION: The results for autologous chondrocyte implantation (ACI) in the treatment of full thickness chondral defects in the knee are encouraging. At present two techniques have been described to retain the chondrocyte suspension within the defect. The first involves using a periosteal cover (ACI-P) and the second involves using a type I/III collagen membrane (ACI-C). To the authors knowledge there are no comparative studies of these two techniques in the current literature. We have therefore undertaken such a study to establish if there is a difference between the 2 techniques based on a clinical and arthroscopic assessment. METHODS: A total of 68 patients with a mean age of 30.52 years with symptomatic articular cartilage defects were randomised to have either ACI-P (33 patients) or ACI-C (35 patients). The mean defect size was 4.54 cm2. All patients were followed up at 24 months. RESULTS: A clinical and functional assessment showed that 74% of patients had a good or excellent result following the ACI-C compared with 67% after the ACI-P at 2 years. Arthroscopy at 1 year also demonstrated similar results for both techniques. However, 36.4% of the ACI-P grafts required shaving for hypertrophy compared with none for the ACI-C grafts at 1 year. DISCUSSION: This study has shown no statistical difference between the clinical outcome of ACI-C versus ACI-P at 2 years. A significant number of patients who had the ACI-P required shaving of a hypertrophied graft. We conclude that there is no advantage in using periosteum as a cover for retaining chondrocytes within an osteochondral defect; as a result we advocate the use of an alternative cover such as a manufactured type I/III collagen membrane.


Assuntos
Transplante de Células/métodos , Condrócitos/transplante , Colágeno Tipo III/uso terapêutico , Colágeno Tipo I/uso terapêutico , Traumatismos do Joelho/cirurgia , Osteocondrite/cirurgia , Adolescente , Adulto , Artroscopia , Cartilagem Articular/patologia , Transplante de Células/patologia , Condrócitos/patologia , Feminino , Humanos , Hipertrofia/patologia , Joelho/patologia , Joelho/cirurgia , Traumatismos do Joelho/patologia , Traumatismos do Joelho/reabilitação , Masculino , Pessoa de Meia-Idade , Osteocondrite/patologia , Osteocondrite/reabilitação , Periósteo/patologia , Estudos Prospectivos , Resultado do Tratamento
19.
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
20.
Plant Physiol ; 106(2): 601-606, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12232353

RESUMO

An open, continuous flow system was used to investigate ethylene production during degreening of maturing seed of mustard (Brassica juncea cv Cutlass and cv Lethbridge 22A) and canola (Brassica napus cv Westar and cv Alto). Isolated mustard seed evolved higher amounts of ethylene than those of canola, and this was particularly evident both early in embryogeny and later during the desiccation phase of seed maturation. The silique walls produced negligible amounts of ethylene in both species. The concentrations of ethylene surrounding seed as they matured within siliques were significantly higher in mustard than in canola, and this interspecies difference was greatest during the seed desiccation phase. In mustard, a 4-fold increase in silique internal ethylene levels was apparent during desiccation. In comparison, only a moderate increase in silique-derived ethylene occurred in canola.

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