Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
BJS Open ; 3(3): 299-304, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31183445

RESUMO

Background: Low-risk differentiated thyroid cancers may, according to the American Thyroid Association (ATA) 2015 guidelines, be managed initially with lobectomy. However, definitive risk categorization requires pathological assessment of the specimen, resulting in completion thyroidectomy being recommended when discordance between preoperative and postoperative staging occurs. This study sought to establish the expected rate of completion thyroidectomy in patients with papillary thyroid cancer (PTC) treated by lobectomy. Methods: Patients with PTC treated over 5 years (2013-2017 inclusive) and meeting the ATA criteria for lobectomy were identified from the prospectively developed database of a high-volume, university department of endocrine surgery. Concordance between the ATA initial and final recommendation, and the putative rate of completion thyroidectomy were calculated. Multivariable analysis was used to assess preoperative factors as predictors of the need for total thyroidectomy. Results: Of 275 patients with PTC who met ATA preoperative criteria for lobectomy there was concordance between this and the final recommendation in 158 (57·5 per cent) and discordance in 117 (43·5 per cent). Most common reasons for discordance were: angioinvasion (30·8 per cent), local invasion (23·9 per cent) or both (20·5 per cent). Four patients (1·5 per cent) had permanent hypoparathyroidism. On multivariable analysis, age, sex, tumour size and family history did not independently predict the final treatment required. Conclusion: Although many patients may be treated adequately with lobectomy, just under half would require completion thyroidectomy. Further work is needed on preoperative risk stratification but, before this, total thyroidectomy remains the treatment of choice for low-risk 1-4-cm PTC in the hands of high-volume thyroid surgeons who can demonstrate low complication rates.


Assuntos
Tratamento Conservador/efeitos adversos , Câncer Papilífero da Tireoide/cirurgia , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Regras de Decisão Clínica , Feminino , Humanos , Hipoparatireoidismo/epidemiologia , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Avaliação de Resultados em Cuidados de Saúde , Complicações Pós-Operatórias/epidemiologia , Período Pós-Operatório , Período Pré-Operatório , Estudos Prospectivos , Medição de Risco , Tireoidectomia/estatística & dados numéricos , Tireoidectomia/tendências
2.
Ecotoxicology ; 26(4): 576-579, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28281096

RESUMO

Soil dwelling earthworms are now adopted more widely in ecotoxicology, so it is vital to establish if standardised test parameters remain applicable. The main aim of this study was to determine the influence of OECD artificial soil on selected soil-dwelling, endogeic earthworm species. In an initial experiment, biomass change in mature Allolobophora chlorotica was recorded in Standard OECD Artificial Soil (AS) and also in Kettering Loam (KL). In a second experiment, avoidance behaviour was recorded in a linear gradient with varying proportions of AS and KL (100% AS, 75% AS + 25% KL, 50% KS + 50% KL, 25% AS + 75% KL, 100% KL) with either A. chlorotica or Octolasion cyaneum. Results showed a significant decrease in A. chlorotica biomass in AS relative to KL, and in the linear gradient, both earthworm species preferentially occupied sections containing higher proportions of KL over AS. Soil texture and specifically % composition and particle size of sand are proposed as key factors that influenced observed results. This research suggests that more suitable substrates are required for ecotoxicology tests with soil dwelling earthworms.


Assuntos
Oligoquetos/fisiologia , Poluentes do Solo/toxicidade , Solo/química , Testes de Toxicidade , Animais , Aprendizagem da Esquiva , Biomassa , Ecotoxicologia , Organização para a Cooperação e Desenvolvimento Econômico
3.
Ecotoxicol Environ Saf ; 141: 64-69, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28319860

RESUMO

Increasing commercial application of silver nanoparticles (Ag NP) and subsequent presence in wastewater and sewage sludge has raised concerns regarding their effects in the aquatic and terrestrial environment. Several studies have employed standardised acute and chronic earthworm-based tests to establish the toxicological effects of Ag NP within soil. These studies have relied heavily on the use of epigiec earthworm species which may have limited ecological relevance in mineral soil. This study assessed the influence of Ag NP (uncoated 80nm powder) and AgNO3 on survival, change in biomass and avoidance behaviour in a soil dwelling (endogiec) species, Allolobophora chlorotica. Earthworms were exposed for 14 days to soils spiked with Ag NP or AgNO3 at 0, 12.5, 25, 50 and 100mgkg-1 either separately for survival and biomass measurement, or combined within a linear gradient to assess avoidance. Avoidance behaviour was shown to provide the most sensitive endpoint with an observable effect at an Ag NP/AgNO3 concentration of 12.5mgkg-1 compared with 50mgkg-1 for biomass change and 100mgkg-1 for survival. Greater mortality was observed in AgNO3 (66.7%) compared with Ag NP-spiked soils (12.5%) at 100mgkg-1, attributed to increased presence of silver ions. Although comparison of results with studies employing Eisenia fetida and Eisenia andrei suggest that the A. chlorotica response to Ag NP is more sensitive, further research employing both epigeic and endogeic earthworms under similar experimental conditions is required to confirm this observation.


Assuntos
Aprendizagem da Esquiva/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Oligoquetos/efeitos dos fármacos , Prata/toxicidade , Poluentes do Solo/toxicidade , Animais , Biomassa , Relação Dose-Resposta a Droga , Íons/farmacologia , Oligoquetos/crescimento & desenvolvimento , Oligoquetos/fisiologia , Solo/química
4.
Endocr Relat Cancer ; 22(1): 99-109, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25595289

RESUMO

Adrenocortical carcinoma (ACC) is an aggressive malignancy with high rates of recurrence following surgical resection. Long noncoding RNAs (lncRNAs) play an important role in cancer development. Pathogenesis of adrenal tumours have been characterised by mRNA, microRNA and methylation expression signatures, but it is unknown if this extends to lncRNAs. This study describes lncRNA expression signatures in ACC, adrenal cortical adenoma (ACA) and normal adrenal cortex (NAC) and presents lncRNAs associated with ACC recurrence to identify novel prognostic and therapeutic targets. RNA was extracted from freshly frozen tissue with confirmation of diagnosis by histopathology. Focused lncRNA and mRNA transcriptome analysis was performed using the ArrayStar Human LncRNA V3.0 microarray. Differentially expressed lncRNAs were validated using quantitative reverse transcriptase-PCR and correlated with clinical outcomes. Microarray of 21 samples (ten ACCs, five ACAs and six NACs) showed distinct patterns of lncRNA expression between each group. A total of 956 lncRNAs were differentially expressed between ACC and NAC, including known carcinogenesis-related lncRNAs such as H19, GAS5, MALAT1 and PRINS (P≤0.05); 85 lncRNAs were differentially expressed between ACC and ACA (P≤0.05). Hierarchical clustering and heat mapping showed ACC samples correctly grouped compared with NAC and ACA. Sixty-six differentially expressed lncRNAs were found to be associated with ACC recurrence (P≤0.05), one of which, PRINS, was validated in a group of 20 ACCs and also found to be associated with metastatic disease on presentation. The pathogenesis of adrenal tumours extends to lncRNA dysregulation and low expression of the lncRNA PRINS is associated with ACC recurrence.


Assuntos
Neoplasias do Córtex Suprarrenal/genética , Recidiva Local de Neoplasia/genética , RNA Longo não Codificante/genética , Adolescente , Neoplasias do Córtex Suprarrenal/metabolismo , Neoplasias do Córtex Suprarrenal/patologia , Adulto , Idoso , Epigenômica , Predisposição Genética para Doença , Humanos , Pessoa de Meia-Idade , Metástase Neoplásica , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/patologia , RNA Longo não Codificante/metabolismo , Análise Serial de Tecidos , Adulto Jovem
5.
Br J Surg ; 101(7): 811-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24752717

RESUMO

BACKGROUND: Patients who present with palpable inguinal melanoma nodal metastasis have two surgical options: inguinal or ilioinguinal lymph node dissection. Indications for either operation remain controversial. This study examined survival and recurrence outcomes following ilioinguinal dissection for patients with palpable inguinal nodal metastasis, and assessed the incidence and preoperative predictors of pelvic nodal metastasis. METHODS: This was a retrospective clinicopathological analysis of consecutive surgical patients with stage III malignant melanoma. All patients underwent a standardized ilioinguinal dissection at a specialist tertiary oncology hospital over a 12-year period (1998-2010). RESULTS: Some 38.9 per cent of 113 patients had metastatic pelvic nodes. Over a median follow-up of 31 months, the 5-year overall survival rate was 28 per cent for patients with metastatic inguinal and pelvic nodes, and 51 per cent for those with inguinal nodal metastasis only (P = 0.002). The nodal basin control rate was 88.5 per cent. Despite no evidence of pelvic node involvement on preoperative computed tomography (CT), six patients (5.3 per cent) with a single metastatic inguinal lymph node had metastatic pelvic lymph nodes. Logistic regression analysis showed that the number of metastatic inguinal nodes (odds ratio 1.56; P = 0.021) and suspicious CT findings (odds ratio 9.89; P = 0.001) were both significantly associated with metastatic pelvic nodes. The specificity of CT was good (89.2 per cent) in detecting metastatic pelvic nodes, but the sensitivity was limited (57.9 per cent). CONCLUSION: Metastatic pelvic nodes are common when palpable metastatic inguinal nodes are present. Long-term survival can be achieved following their resection by ilioinguinal dissection. As metastatic pelvic nodes cannot be diagnosed reliably by preoperative CT, patients presenting with palpable inguinal nodal metastasis should be considered for ilioinguinal dissection.


Assuntos
Excisão de Linfonodo/métodos , Melanoma/cirurgia , Neoplasias Primárias Desconhecidas/cirurgia , Neoplasias Cutâneas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Virilha , Humanos , Ílio , Modelos Logísticos , Excisão de Linfonodo/mortalidade , Metástase Linfática , Masculino , Melanoma/mortalidade , Melanoma/patologia , Melanoma/secundário , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estadiamento de Neoplasias/métodos , Neoplasias Primárias Desconhecidas/mortalidade , Neoplasias Primárias Desconhecidas/patologia , Palpação , Estudos Retrospectivos , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/patologia , Taxa de Sobrevida , Adulto Jovem
6.
Appl Opt ; 34(36): 8409-21, 1995 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-21068962

RESUMO

A full-field, time-resolved interferometric method for the characterization of sparse, polydisperse spray systems is reported. The method makes use of the angular intensity oscillations in the wide-angle forward-scatter region. A pulsed laser is used to illuminate a planar sheet through the spray, which is imaged, out of focus, from the 45°direction. The image consists of a set of out-of-focus spots, each of which represents an individual droplet, and superimposed on which is a set of fringes corresponding to the angular intensity oscillations of that droplet. Macrophotographic recording with high-resolution digitization for image analysis provides a full-field capability. The spatial frequency of fringes on each spot in the image plane is dependent on the diameter of the corresponding droplet in the object plane, and a simple geometric analysis is shown to be appropriate for the calculation of the spatial frequency of fringes as a function of droplet size. Images are analyzed automatically by a software suite that uses Gaussian blur, Canny edge detection, and Hough transforms to locate individual droplets in the image field. Fringe spatial frequency is then determined by least-squares fitting to a Chirp function. The method is applicable to droplets with diameters in the range of several millimeters to several hundred millimeters and number densities of up to 10(3) to 10(4). The accuracy of the method for droplet-size determination has been evaluated by measurements of monodisperse aerosols of known droplet size, and measurements of droplet-size distribution in a polydisperse aerosol produced by a gasoline fuel injector are also presented. An extension of the method, using high-speed photography to measure two components of velocity in addition to size and position, is discussed. A two-wavelength approach may also offer the capability to measure the concentration of model fuel additives in droplets, and the results of a feasibility study are described.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...