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1.
J Acoust Soc Am ; 151(5): 2931, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35649945

RESUMO

Opaque face masks harm communication by preventing speech-reading (lip-reading) and attenuating high-frequency sound. Although transparent masks and shields (visors) with clear plastic inserts allow speech-reading, they usually create more sound attenuation than opaque masks. Consequently, an iterative process was undertaken to create a better design, and the instructions to make it are published. The experiments showed that lowering the mass of the plastic inserts decreases the high-frequency sound attenuation. A shield with a clear thermoplastic polyurethane (TPU) panel had an insertion loss of (2.0 ± 1.1) dB for 1.25-8 kHz, which improves on previous designs that had attenuations of 11.9 dB and above. A cloth mask with a TPU insert was designed and had an insertion loss of (4.6 ± 2.3) dB for 2-8 kHz, which is better than the 9-22 dB reported previously in the literature. The speech intelligibility index was also evaluated. Investigations to improve measurement protocols that use either mannikins or human talkers were undertaken. Manufacturing variability and inconsistency of human speaking were greater sources of experimental error than fitting differences. It was shown that measurements from a mannikin could match those from humans if insertion losses from four human talkers were averaged.


Assuntos
Máscaras , Percepção da Fala , Acústica , Humanos , Plásticos , Inteligibilidade da Fala
2.
Pharm Stat ; 21(3): 514-524, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34859565

RESUMO

The problem of associating a continuous covariate, or biomarker, against a time-to-event outcome, is that it often requires categorisation of the covariate. This can lead to bias, loss of information and a poor representation of any underlying relationship. Here, two methods are proposed for estimating the effects of a continuous covariate on a time-to-event endpoint using weighted kernel estimators. The first method aims to estimate a density function for a time-to-event endpoint conditional on some covariate value whilst the second uses a joint density estimator. The results are visualisations in the form of surface plots that show the effects of a covariate without any need for categorisation. Both methods can aid interpretation and analysis of covariates against a time-to-event endpoint.


Assuntos
Viés , Simulação por Computador , Humanos
3.
Ann Surg ; 269(3): 520-529, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-29068800

RESUMO

OBJECTIVE AND BACKGROUND: Local and distant disease recurrence are frequently observed following pancreatic cancer resection, but an improved understanding of resection margin assessment is required to aid tailored therapies. METHODS: Analyses were carried out to assess the association between clinical characteristics and margin involvement as well as the effects of individual margin involvement on site of recurrence and overall and recurrence-free survival using individual patient data from the European Study Group for Pancreatic Cancer (ESPAC)-3 randomized controlled trial. RESULTS: There were 1151 patients, of whom 505 (43.9%) had an R1 resection. The median and 95% confidence interval (CI) overall survival was 24.9 (22.9-27.2) months for 646 (56.1%) patients with resection margin negative (R0 >1 mm) tumors, 25.4 (21.6-30.4) months for 146 (12.7%) patients with R1<1 mm positive resection margins, and 18.7 (17.2-21.1) months for 359 (31.2%) patients with R1-direct positive margins (P < 0.001). In multivariable analysis, overall R1-direct tumor margins, poor tumor differentiation, positive lymph node status, WHO performance status ≥1, maximum tumor size, and R1-direct posterior resection margin were all independently significantly associated with reduced overall and recurrence-free survival. Competing risks analysis showed that overall R1-direct positive resection margin status, positive lymph node status, WHO performance status 1, and R1-direct positive superior mesenteric/medial margin resection status were all significantly associated with local recurrence. CONCLUSIONS: R1-direct resections were associated with significantly reduced overall and recurrence-free survival following pancreatic cancer resection. Resection margin involvement was also associated with an increased risk for local recurrence.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Ductal Pancreático/tratamento farmacológico , Margens de Excisão , Recidiva Local de Neoplasia/etiologia , Pancreatectomia , Neoplasias Pancreáticas/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Ductal Pancreático/mortalidade , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/cirurgia , Quimioterapia Adjuvante , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Fluoruracila/uso terapêutico , Humanos , Leucovorina/uso terapêutico , Recidiva Local de Neoplasia/mortalidade , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Prognóstico , Estudos Prospectivos , Estudos Retrospectivos , Análise de Sobrevida , Gencitabina
4.
J Acoust Soc Am ; 145(1): 372, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30710912

RESUMO

An investigation has been carried out to examine the impact of different levels of classroom noise on adolescents' performance on reading and vocabulary-learning tasks. A total of 976 English high school pupils (564 aged 11 to 13 years and 412 aged 14 to 16 years) completed reading tasks on laptop computers while exposed to different levels of classroom noise played through headphones. The tasks consisted of reading science texts, which were followed by multiple-choice questions probing comprehension and word learning. Number of questions attempted, times taken to read the texts and to answer questions were recorded, as well as correct answers to different types of question. The study consisted of two similar experiments, the first comparing performance in classroom noise at levels of 50 and 70 dB LAeq; and the second at levels of 50 and 64 dB LAeq. The results showed that the performance of all pupils was significantly negatively affected in the 70 dB LAeq condition, for the number of questions attempted and the accuracy of answers to factual and word learning questions. It was harder to discern effects at 64 dB LAeq, this level of noise having a detrimental effect upon the older pupils only.


Assuntos
Compreensão , Ruído/efeitos adversos , Leitura , Desempenho Acadêmico , Adolescente , Criança , Feminino , Humanos , Masculino , Instituições Acadêmicas/normas
5.
Gut ; 66(9): 1665-1676, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-27325420

RESUMO

BACKGROUND AND AIMS: The role of GATA factors in cancer has gained increasing attention recently, but the function of GATA6 in pancreatic ductal adenocarcinoma (PDAC) is controversial. GATA6 is amplified in a subset of tumours and was proposed to be oncogenic, but high GATA6 levels are found in well-differentiated tumours and are associated with better patient outcome. By contrast, a tumour-suppressive function of GATA6 was demonstrated using genetic mouse models. We aimed at clarifying GATA6 function in PDAC. DESIGN: We combined GATA6 silencing and overexpression in PDAC cell lines with GATA6 ChIP-Seq and RNA-Seq data, in order to understand the mechanism of GATA6 functions. We then confirmed some of our observations in primary patient samples, some of which were included in the ESPAC-3 randomised clinical trial for adjuvant therapy. RESULTS: GATA6 inhibits the epithelial-mesenchymal transition (EMT) in vitro and cell dissemination in vivo. GATA6 has a unique proepithelial and antimesenchymal function, and its transcriptional regulation is direct and implies, indirectly, the regulation of other transcription factors involved in EMT. GATA6 is lost in tumours, in association with altered differentiation and the acquisition of a basal-like molecular phenotype, consistent with an epithelial-to-epithelial (ET2) transition. Patients with basal-like GATA6low tumours have a shorter survival and have a distinctly poor response to adjuvant 5-fluorouracil (5-FU)/leucovorin. However, modulation of GATA6 expression in cultured cells does not directly regulate response to 5-FU. CONCLUSIONS: We provide mechanistic insight into GATA6 tumour-suppressive function, its role as a regulator of canonical epithelial differentiation, and propose that loss of GATA6 expression is both prognostic and predictive of response to adjuvant therapy.


Assuntos
Carcinoma Ductal Pancreático , Transição Epitelial-Mesenquimal/genética , Fluoruracila/farmacologia , Fator de Transcrição GATA6 , Neoplasias Pancreáticas , Animais , Antimetabólitos Antineoplásicos/farmacologia , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Quimioterapia Adjuvante/métodos , Fator de Transcrição GATA6/genética , Fator de Transcrição GATA6/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Estatística como Assunto
6.
Lancet Oncol ; 18(4): 486-499, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28259610

RESUMO

BACKGROUND: Erlotinib is an EGFR tyrosine kinase inhibitor that has shown a significant but only marginally improved median overall survival when combined with gemcitabine in patients with locally advanced and metastatic pancreatic cancer. Vandetanib is a novel tyrosine kinase inhibitor of VEGFR2, RET, and EGFR, all of which are in involved in the pathogenesis of pancreatic cancer. We investigated the clinical efficacy of vandetanib when used in combination with gemcitabine in patients with advanced pancreatic cancer. METHODS: The Vandetanib in Pancreatic Cancer (ViP) trial was a phase 2 double-blind, multicentre, randomised placebo-controlled trial in previously untreated adult patients (aged ≥18 years) diagnosed with locally advanced or metastatic carcinoma of the pancreas confirmed by cytology or histology. Patients had to have an Eastern Cooperative Oncology Group (ECOG) score of 0-2 and a documented life expectancy of at least 3 months. Patients were randomly assigned 1:1 to receive vandetanib plus gemcitabine (vandetanib group) or placebo plus gemcitabine (placebo group) according to pre-generated sequences produced on the principle of randomly permuted blocks with variable block sizes of two and four. Patients were stratified at randomisation by disease stage and ECOG performance status. All patients received gemcitabine 1000 mg/m2 as a 30-min intravenous infusion, weekly, for 7 weeks followed by a 1-week break, followed by a cycle of 3 weeks of treatment with a 1-week break, until disease progression, and either oral vandetanib 300 mg per day once daily or matching placebo. Patients and investigators were masked to treatment assignment. The primary outcome measure was overall survival (defined as the difference in time between randomisation and death from any cause or the censor date) in the intention-to-treat population. This trial has been completed and the final results are reported. The study is registered at EudraCT, number 2007-004299-38, and ISRCTN, number ISRCTN96397434. FINDINGS: Patients were screened and enrolled between Oct 24, 2011, and Oct 7, 2013. Of 381 patients screened, 142 eligible patients were randomly assigned to treatment (72 to the vandetanib group and 70 to the placebo group). At database lock on July 15, 2015, at a median follow-up of 24·9 months (IQR 24·3 to not attainable), 131 patients had died: 70 (97%) of 72 in the vandetanib group and 61 (87%) of 70 in the placebo group. The median overall survival was 8·83 months (95% CI 7·11-11·58) in the vandetanib group and 8·95 months (6·55-11·74) in the placebo group (hazard ratio 1·21, 80·8% CI 0·95-1·53; log rank χ21df 1·1, p=0·303). The most common grade 3-4 adverse events were neutropenia (35 [49%] of 72 patients in the vandetanib group vs 22 [31%] of 70 in the placebo group), thrombocytopenia (20 [28%] vs 16 [23%]), hypertension (nine [13%] vs 11 [16%]), leucopenia (12 [17%] vs 13 [19%]), and fatigue (17 [24%] vs 15 [21%]). No treatment-related deaths occurred during the study. INTERPRETATION: The addition of vandetanib to gemcitabine monotherapy did not improve overall survival in advanced pancreatic cancer. Tyrosine kinase inhibitors might still have potential in the treatment of pancreatic cancer but further development requires the identification of biomarkers to specifically identify responsive cancer subtypes. FUNDING: Cancer Research UK and AstraZeneca.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Ductal Pancreático/tratamento farmacológico , Neoplasias Pancreáticas/tratamento farmacológico , Adulto , Idoso , Carcinoma Ductal Pancreático/secundário , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Pancreáticas/patologia , Piperidinas/administração & dosagem , Prognóstico , Quinazolinas/administração & dosagem , Taxa de Sobrevida , Gencitabina
7.
BMC Med Res Methodol ; 17(1): 53, 2017 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-28388943

RESUMO

BACKGROUND: ROC (receiver operating characteristic) curve analysis is well established for assessing how well a marker is capable of discriminating between individuals who experience disease onset and individuals who do not. The classical (standard) approach of ROC curve analysis considers event (disease) status and marker value for an individual as fixed over time, however in practice, both the disease status and marker value change over time. Individuals who are disease-free earlier may develop the disease later due to longer study follow-up, and also their marker value may change from baseline during follow-up. Thus, an ROC curve as a function of time is more appropriate. However, many researchers still use the standard ROC curve approach to determine the marker capability ignoring the time dependency of the disease status or the marker. METHODS: We comprehensively review currently proposed methodologies of time-dependent ROC curves which use single or longitudinal marker measurements, aiming to provide clarity in each methodology, identify software tools to carry out such analysis in practice and illustrate several applications of the methodology. We have also extended some methods to incorporate a longitudinal marker and illustrated the methodologies using a sequential dataset from the Mayo Clinic trial in primary biliary cirrhosis (PBC) of the liver. RESULTS: From our methodological review, we have identified 18 estimation methods of time-dependent ROC curve analyses for censored event times and three other methods can only deal with non-censored event times. Despite the considerable numbers of estimation methods, applications of the methodology in clinical studies are still lacking. CONCLUSIONS: The value of time-dependent ROC curve methods has been re-established. We have illustrated the methods in practice using currently available software and made some recommendations for future research.


Assuntos
Área Sob a Curva , Biomarcadores/análise , Cirrose Hepática Biliar/diagnóstico , Modelos Estatísticos , Curva ROC , Simulação por Computador , Humanos , Fígado/patologia
8.
Br J Cancer ; 114(5): 510-8, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26931369

RESUMO

BACKGROUND: Preclinical studies suggest that chemotherapy may enhance the immune response against pancreatic cancer. METHODS: The levels of granulocyte macrophage-colony-stimulating factor (GM-CSF) and interleukin-6 (IL-6) and the associated inflammatory marker C-reactive protein (CRP) were assessed in 38 patients receiving gemcitabine and capecitabine combination chemotherapy for advanced pancreatic cancer within the TeloVac trial. Apoptosis (M30) and total immune response (delayed-type hypersensitivity and/or T-cell response) were also assessed and levels of apoptosis induction correlated with immune response. The telomerase GV1001 vaccine was given either sequentially (n=18) or concomitantly (n=24) with the combination chemotherapy. RESULTS: There were no differences between baseline and post-treatment levels of CRP (P=0.19), IL-6 (P=0.19) and GM-CSF (P=0.71). There was a positive correlation between post-chemotherapy CRP and IL-6 levels (r=0.45, P=0.005) and between CRP with carbohydrate antigen-19-9 (CA19-9) levels at baseline (r=0.45, P=0.015) and post treatment (r=0.40, P=0.015). The change in CRP and IL-6 levels was positively correlated (r=0.40, P=0.012). Hazard ratios (95% CI) for baseline CA19-9 (1.30 (1.07-1.59), P=0.009) and CRP (1.55 (1.00-2.39), P=0.049) levels were each independently predictive of survival. The M30 mean matched differences between pre- and post-chemotherapy showed evidence of apoptosis in both the sequential (P=0.058) and concurrent (P=0.0018) chemoimmunotherapy arms. Respectively, 5 of 10 and 9 of 20 patients had a positive immune response but there was no association with apoptosis. CONCLUSIONS: Combination gemcitabine and capecitabine chemotherapy did not affect circulating levels of GM-CSF, IL-6 and CRP. Chemotherapy-induced apoptosis was not associated with the immunogenicity induced by the GV1001 vaccine in advanced pancreatic cancer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Vacinas Anticâncer/uso terapêutico , Carcinoma Ductal Pancreático/tratamento farmacológico , Neoplasias Pancreáticas/tratamento farmacológico , Fragmentos de Peptídeos/uso terapêutico , Telomerase/uso terapêutico , Adulto , Idoso , Apoptose/imunologia , Proteína C-Reativa/imunologia , Antígeno CA-19-9/metabolismo , Capecitabina/administração & dosagem , Carcinoma Ductal Pancreático/imunologia , Carcinoma Ductal Pancreático/patologia , Proliferação de Células , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Humanos , Hipersensibilidade Tardia/imunologia , Interleucina-6/imunologia , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/patologia , Linfócitos T/imunologia , Gencitabina
9.
Br J Cancer ; 115(7): 887-94, 2016 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-27584663

RESUMO

BACKGROUND: Diabetes mellitus is frequently observed in pancreatic cancer patients and is both a risk factor and an early manifestation of the disease. METHODS: We analysed the prognostic impact of diabetes on the outcome of pancreatic cancer following resection and adjuvant chemotherapy using individual patient data from three European Study Group for Pancreatic Cancer randomised controlled trials. Analyses were carried out to assess the association between clinical characteristics and the presence of preoperative diabetes, as well as the effect of diabetic status on overall survival. RESULTS: In total, 1105 patients were included in the analysis, of whom 257 (23%) had confirmed diabetes and 848 (77%) did not. Median (95% confidence interval (CI)) unadjusted overall survival in non-diabetic patients was 22.3 (20.8-24.1) months compared with 18.8 (16.9-22.1) months for diabetic patients (P=0.24). Diabetic patients were older, had increased weight and more co-morbidities. Following adjustment, multivariable analysis demonstrated that diabetic patients had an increased risk of death (hazard ratio: 1.19 (95% CI 1.01, 1.40), P=0.034). Maximum tumour size of diabetic patients was larger at randomisation (33.6 vs 29.7 mm, P=0.026). CONCLUSIONS: Diabetes mellitus was associated with increased tumour size and reduced survival following pancreatic cancer resection and adjuvant chemotherapy.


Assuntos
Carcinoma Ductal Pancreático/mortalidade , Diabetes Mellitus/epidemiologia , Neoplasias Pancreáticas/mortalidade , Idoso , Idoso de 80 Anos ou mais , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/cirurgia , Quimioterapia Adjuvante , Ensaios Clínicos Fase III como Assunto/estatística & dados numéricos , Comorbidade , Diabetes Mellitus/tratamento farmacológico , Feminino , Humanos , Insulina/uso terapêutico , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto/estatística & dados numéricos , Sobrepeso/epidemiologia , Pancreatectomia , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/cirurgia , Prognóstico , Modelos de Riscos Proporcionais , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Fatores de Risco , Resultado do Tratamento , Carga Tumoral
10.
Clin Gastroenterol Hepatol ; 14(6): 875-886.e6, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26775025

RESUMO

BACKGROUND & AIMS: GALAD and BALAD-2 are statistical models for estimating the likelihood of the presence of hepatocellular carcinoma (HCC) in individual patients with chronic liver disease and the survival of patients with HCC, respectively. Both models use objective measures, particularly the serum markers α-fetoprotein (AFP), AFP-L3, and des-γ-carboxyprothrombin. We aimed to validate these models in an international cohort of patients with HCC and assess their clinical performance. METHODS: We collected data on cancer diagnosis and outcomes of 6834 patients (2430 with HCC and 4404 with chronic liver disease) recruited from Germany, Japan, and Hong Kong. We also collected data from 229 patients with other hepatobiliary tract cancers (cholangiocarcinoma or pancreatic adenocarcinoma) and 92 healthy individuals (controls). For reference, the original UK cohort (on which the GALAD model initially was built and BALAD-2 was validated) was included in the analysis. We assessed the effects of tumor size and etiology on GALAD model performance, and its ability to correctly discriminate HCC from other hepatobiliary cancers. We assessed the performance of BALAD-2 in patients with different stages of HCC. RESULTS: In all cohorts, the area under the receiver operating characteristic curve (AUROC), quantifying the ability of GALAD to discriminate patients with HCC from patients with chronic liver disease, was greater than 0.90-similar to the series on which the model originally was built (AUROC, 0.97). GALAD discriminated patients with HCC from those with other hepatobiliary cancers with an AUROC value of 0.95; values were slightly lower for patients with small unifocal HCCs, ranging from 0.85 to 0.95. Etiology and treatment of chronic viral hepatitis had no effect on the performance of this model. BALAD-2 analysis assigned patients with HCC to 4 distinct prognostic groups-overall and when patients were stratified according to disease stage. CONCLUSIONS: We validated the performance of the GALAD and BALAD-2 models for the diagnosis of HCC and predicting patient survival, respectively (based on levels of the serum markers AFP, AFP-L3, and des-γ-carboxyprothrombin), in an international cohort of almost 7000 patients. These systems might be used in HCC surveillance and determination of patient prognosis.


Assuntos
Biomarcadores/sangue , Carcinoma Hepatocelular/diagnóstico , Técnicas de Apoio para a Decisão , Testes Diagnósticos de Rotina/métodos , Neoplasias Hepáticas/diagnóstico , Adulto , Idoso , Ásia , Estudos de Coortes , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida
11.
Ann Rheum Dis ; 75(2): 362-7, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25475116

RESUMO

BACKGROUND: Alkaptonuria (AKU) is a serious genetic disease characterised by premature spondyloarthropathy. Homogentisate-lowering therapy is being investigated for AKU. Nitisinone decreases homogentisic acid (HGA) in AKU but the dose-response relationship has not been previously studied. METHODS: Suitability Of Nitisinone In Alkaptonuria 1 (SONIA 1) was an international, multicentre, randomised, open-label, no-treatment controlled, parallel-group, dose-response study. The primary objective was to investigate the effect of different doses of nitisinone once daily on 24-h urinary HGA excretion (u-HGA24) in patients with AKU after 4 weeks of treatment. Forty patients were randomised into five groups of eight patients each, with groups receiving no treatment or 1 mg, 2 mg, 4 mg and 8 mg of nitisinone. FINDINGS: A clear dose-response relationship was observed between nitisinone and the urinary excretion of HGA. At 4 weeks, the adjusted geometric mean u-HGA24 was 31.53 mmol, 3.26 mmol, 1.44 mmol, 0.57 mmol and 0.15 mmol for the no treatment or 1 mg, 2 mg, 4 mg and 8 mg doses, respectively. For the most efficacious dose, 8 mg daily, this corresponds to a mean reduction of u-HGA24 of 98.8% compared with baseline. An increase in tyrosine levels was seen at all doses but the dose-response relationship was less clear than the effect on HGA. Despite tyrosinaemia, there were no safety concerns and no serious adverse events were reported over the 4 weeks of nitisinone therapy. CONCLUSIONS: In this study in patients with AKU, nitisinone therapy decreased urinary HGA excretion to low levels in a dose-dependent manner and was well tolerated within the studied dose range. TRIAL REGISTRATION NUMBER: EudraCT number: 2012-005340-24. Registered at ClinicalTrials.gov: NCTO1828463.


Assuntos
Alcaptonúria/tratamento farmacológico , Cicloexanonas/administração & dosagem , Inibidores Enzimáticos/administração & dosagem , Ácido Homogentísico/urina , Nitrobenzoatos/administração & dosagem , Adulto , Alcaptonúria/sangue , Alcaptonúria/urina , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Ácido Homogentísico/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Projetos de Pesquisa , Tirosina/sangue
12.
Stat Med ; 35(14): 2406-21, 2016 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-26842429

RESUMO

This paper introduces a new simple divergence measure between two survival distributions. For two groups of patients, the divergence measure between their associated survival distributions is based on the integral of the absolute difference in probabilities that a patient from one group dies at time t and a patient from the other group survives beyond time t and vice versa. In the case of non-crossing hazard functions, the divergence measure is closely linked to the Harrell concordance index, C, the Mann-Whitney test statistic and the area under a receiver operating characteristic curve. The measure can be used in a dynamic way where the divergence between two survival distributions from time zero up to time t is calculated enabling real-time monitoring of treatment differences. The divergence can be found for theoretical survival distributions or can be estimated non-parametrically from survival data using Kaplan-Meier estimates of the survivor functions. The estimator of the divergence is shown to be generally unbiased and approximately normally distributed. For the case of proportional hazards, the constituent parts of the divergence measure can be used to assess the proportional hazards assumption. The use of the divergence measure is illustrated on the survival of pancreatic cancer patients. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Estimativa de Kaplan-Meier , Modelos Estatísticos , Bioestatística , Humanos , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/terapia , Modelos de Riscos Proporcionais , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Estatísticas não Paramétricas , Equivalência Terapêutica
13.
J Acoust Soc Am ; 140(1): EL79, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27475217

RESUMO

Microphone wind noise can corrupt outdoor recordings even when wind shields are used. When monitoring wind turbine noise, microphone wind noise is almost inevitable because measurements cannot be made in still conditions. The effect of microphone wind noise on two amplitude modulation (AM) metrics is quantified in a simulation, showing that even at low wind speeds of 2.5 m/s errors of over 4 dBA can result. As microphone wind noise is intermittent, a wind noise detection algorithm is used to automatically find uncorrupted sections of the recording, and so recover the true AM metrics to within ±2/±0.5 dBA.

14.
J Acoust Soc Am ; 140(3): 1858, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27914424

RESUMO

One criterion in the design of binaural sound scenes in audio production is the extent to which the intended speech message is correctly understood. Object-based audio broadcasting systems have permitted sound editors to gain more access to the metadata (e.g., intensity and location) of each sound source, providing better control over speech intelligibility. The current study describes and evaluates a binaural distortion-weighted glimpse proportion metric-BiDWGP-which is motivated by better-ear glimpsing and binaural masking level differences. BiDWGP predicts intelligibility from two alternative input forms: either binaural recordings or monophonic recordings from each sound source along with their locations. Two listening experiments were performed with stationary noise and competing speech, one in the presence of a single masker, the other with multiple maskers, for a variety of spatial configurations. Overall, BiDWGP with both input forms predicts listener keyword scores with correlations of 0.95 and 0.91 for single- and multi-masker conditions, respectively. When considering masker type separately, correlations rise to 0.95 and above for both types of maskers. Predictions using the two input forms are very similar, suggesting that BiDWGP can be applied to the design of sound scenes where only individual sound sources and their locations are available.


Assuntos
Inteligibilidade da Fala , Ruído , Mascaramento Perceptivo , Percepção da Fala , Teste do Limiar de Recepção da Fala
15.
Blood ; 122(26): 4253-8, 2013 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-24128861

RESUMO

Fludarabine plus cyclophosphamide (FC) is the chemotherapy backbone of modern chronic lymphocytic leukemia (CLL) treatment. CYP2B6 is a polymorphic cytochrome P450 isoform that converts cyclophosphamide to its active form. This study investigated the possible impact of genetic variation in CYP2B6 on response to FC chemotherapy in CLL. Available DNA samples from the LRF CLL4 trial, which compared chlorambucil, fludarabine, and FC, were screened by TaqMan real-time polymerase chain reaction assays for CYP2B6 SNPs c.516G>T and c.785A>G, which define the most common variant allele (*6). Among the 455 samples successfully genotyped, 265 (58.2%), 134 (29.5%), and 29 (6.4%) were classified as *1/*1, *1/*6, and *6/*6, respectively. Patients expressing at least one *6 allele were significantly less likely to achieve a complete response (CR) after FC (odds ratio 0.27; P = .004) but not chlorambucil or fludarabine. Analysis of individual response indicators confirmed that this inferior response resulted from impaired cytoreduction rather than delayed hemopoietic recovery. Multivariate analysis controlling for age, gender, stage, IGHV mutational status, 11q deletion, and TP53 deletion/mutation identified CYP2B6*6 and TP53 mutation/deletion as the only independent determinants of CR attainment after FC. Our study provides the first demonstration that host pharmacogenetics can influence therapeutic response in CLL. This trial is registered as an International Standard Randomised Control Trial, number NCT 58585610 at www.clinicaltrials.gov.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Hidrocarboneto de Aril Hidroxilases/genética , Ciclofosfamida/administração & dosagem , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/genética , Vidarabina/análogos & derivados , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Antineoplásicos Alquilantes/administração & dosagem , Antineoplásicos Alquilantes/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Ciclofosfamida/efeitos adversos , Citocromo P-450 CYP2B6 , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Farmacogenética , Prognóstico , Indução de Remissão , Vidarabina/administração & dosagem , Vidarabina/efeitos adversos
17.
J Acoust Soc Am ; 137(6): EL483-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26093459

RESUMO

Time-domain prediction models have been developed for auditorium reflectors and room acoustic diffusers. The models are time-domain equivalents of the single-frequency formulations that exploit the Kirchhoff boundary conditions. Consequently, they are approximate, wave-based solutions to the Kirchhoff integral equation using surface meshes. The new time-domain formulations are validated by comparison to their frequency-domain equivalents for three different surfaces: a plane surface, a curved reflector, and a Schroeder diffuser. In terms of computation time and accuracy, the new models lie between the finite difference time domain and geometric room models.

18.
J Acoust Soc Am ; 137(3): 1602-4, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25786971

RESUMO

In 2013, Guinness World Records awarded tank number 1 at the Inchindown oil despository, Ross-shire, Scotland, the record for the "longest echo" at 75 s. Guinness World Records calls it the longest echo because that was the name of the record that was broken, however, the correct name for the phenomenon measured is reverberation. This Letter has been written to document this unique acoustic space where the reverberation time is 112 s at 125 Hz, to detail the methodology for those who wish to attempt to break the record, and to discuss why the tank is so uniquely reverberant.

19.
J Acoust Soc Am ; 137(1): 177-88, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25618049

RESUMO

An acoustic survey of secondary schools in England has been undertaken. Room acoustic parameters and background noise levels were measured in 185 unoccupied spaces in 13 schools to provide information on the typical acoustic environment of secondary schools. The unoccupied acoustic and noise data were correlated with various physical characteristics of the spaces. Room height and the amount of glazing were related to the unoccupied reverberation time and therefore need to be controlled to reduce reverberation to suitable levels for teaching and learning. Further analysis of the unoccupied data showed that the introduction of legislation relating to school acoustics in England and Wales in 2003 approximately doubled the number of school spaces complying with current standards. Noise levels were also measured during 274 lessons to examine typical levels generated during teaching activities in secondary schools and to investigate the influence of acoustic design on working noise levels in the classroom. Comparison of unoccupied and occupied data showed that unoccupied acoustic conditions affect the noise levels occurring during lessons. They were also related to the time spent in disruption to the lessons (e.g., students talking or shouting) and so may also have an impact upon student behavior in the classroom.


Assuntos
Acústica , Arquitetura de Instituições de Saúde , Ruído , Instituições Acadêmicas , Adolescente , Comportamento do Adolescente , Inglaterra , Arquitetura de Instituições de Saúde/legislação & jurisprudência , Pisos e Cobertura de Pisos , Atividades Humanas , Humanos , Ruído/prevenção & controle , Instituições Acadêmicas/legislação & jurisprudência , Percepção da Fala , Ensino
20.
Lancet Oncol ; 15(8): 829-40, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24954781

RESUMO

BACKGROUND: We aimed to assess the efficacy and safety of sequential or simultaneous telomerase vaccination (GV1001) in combination with chemotherapy in patients with locally advanced or metastatic pancreatic cancer. METHODS: TeloVac was a three-group, open-label, randomised phase 3 trial. We recruited patients from 51 UK hospitals. Eligible patients were treatment naive, aged older than 18 years, with locally advanced or metastatic pancreatic ductal adenocarcinoma, and Eastern Cooperative Oncology Group performance status of 0-2. Patients were randomly assigned (1:1:1) to receive either chemotherapy alone, chemotherapy with sequential GV1001 (sequential chemoimmunotherapy), or chemotherapy with concurrent GV1001 (concurrent chemoimmunotherapy). Treatments were allocated with equal probability by means of computer-generated random permuted blocks of sizes 3 and 6 in equal proportion. Chemotherapy included six cycles of gemcitabine (1000 mg/m(2), 30 min intravenous infusion, at days 1, 8, and 15) and capecitabine (830 mg/m(2) orally twice daily for 21 days, repeated every 28 days). Sequential chemoimmunotherapy included two cycles of combination chemotherapy, then an intradermal lower abdominal injection of granulocyte-macrophage colony-stimulating factor (GM-CSF; 75 µg) and GV1001 (0·56 mg; days 1, 3, and 5, once on weeks 2-4, and six monthly thereafter). Concurrent chemoimmunotherapy included giving GV1001 from the start of chemotherapy with GM-CSF as an adjuvant. The primary endpoint was overall survival; analysis was by intention to treat. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN4382138. FINDINGS: The first patient was randomly assigned to treatment on March 29, 2007, and the trial was terminated on March 27, 2011. Of 1572 patients screened, 1062 were randomly assigned to treatment (358 patients were allocated to the chemotherapy group, 350 to the sequential chemoimmunotherapy group, and 354 to the concurrent chemoimmunotherapy group). We recorded 772 deaths; the 290 patients still alive were followed up for a median of 6·0 months (IQR 2·4-12·2). Median overall survival was not significantly different in the chemotherapy group than in the sequential chemoimmunotherapy group (7·9 months [95% CI 7·1-8·8] vs 6·9 months [6·4-7·6]; hazard ratio [HR] 1·19, 98·25% CI 0·97-1·48, p=0·05), or in the concurrent chemoimmunotherapy group (8·4 months [95% CI 7·3-9·7], HR 1·05, 98·25% CI 0·85-1·29, p=0·64; overall log-rank of χ(2)2df=4·3; p=0·11). The commonest grade 3-4 toxic effects were neutropenia (68 [19%] patients in the chemotherapy group, 58 [17%] patients in the sequential chemoimmunotherapy group, and 79 [22%] patients in the concurrent chemoimmunotherapy group; fatigue (27 [8%] in the chemotherapy group, 35 [10%] in the sequential chemoimmunotherapy group, and 44 [12%] in the concurrent chemoimmunotherapy group); and pain (34 [9%] patients in the chemotherapy group, 39 [11%] in the sequential chemoimmunotherapy group, and 41 [12%] in the concurrent chemoimmunotherapy group). INTERPRETATION: Adding GV1001 vaccination to chemotherapy did not improve overall survival. New strategies to enhance the immune response effect of telomerase vaccination during chemotherapy are required for clinical efficacy. FUNDING: Cancer Research UK and KAEL-GemVax.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Vacinas Anticâncer/administração & dosagem , Ductos Pancreáticos , Neoplasias Pancreáticas/tratamento farmacológico , Fragmentos de Peptídeos/administração & dosagem , Telomerase/administração & dosagem , Adenocarcinoma/secundário , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Vacinas Anticâncer/efeitos adversos , Capecitabina , Proliferação de Células , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Intervalo Livre de Doença , Fadiga/induzido quimicamente , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/análogos & derivados , Fator Estimulador de Colônias de Granulócitos e Macrófagos/administração & dosagem , Humanos , Fatores Imunológicos/administração & dosagem , Análise de Intenção de Tratamento , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Neutropenia/induzido quimicamente , Dor/induzido quimicamente , Neoplasias Pancreáticas/patologia , Fragmentos de Peptídeos/efeitos adversos , Linfócitos T/imunologia , Telomerase/efeitos adversos , Gencitabina
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