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1.
Int J Cancer ; 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38685816

RESUMO

Pembrolizumab has received approval in the UK as first-line monotherapy for recurrent and/or metastatic HNSCC (R/M HNSCC) following the results of the KEYNOTE-048 trial, which demonstrated a longer overall survival (OS) in comparison to the EXTREME chemotherapy regimen in patients with a combined positive score (CPS) ≥1. In this article, we provide retrospective real-world data on the role of pembrolizumab monotherapy as first-line systemic therapy for HNSCC across 18 centers in the UK from March 20, 2020 to May 31, 2021. 211 patients were included, and in the efficacy analysis, the objective response rate (ORR) was 24.7%, the median progression-free survival (PFS) was 4.8 months (95% confidence interval [CI]: 3.6-6.1), and the median OS was 10.8 months (95% CI 9.0-12.5). Pembrolizumab monotherapy was well tolerated, with 18 patients having to stop treatment owing to immune-related adverse events (irAEs). 53 patients proceeded to second-line treatment with a median PFS2 of 10.2 months (95% CI: 8.8-11.5). Moreover, patients with documented irAEs had a statistically significant longer median PFS (11.3 vs. 3.3 months; log-rank p value = <.001) and median OS (18.8 vs. 8.9 months; log-rank p value <.001). The efficacy and safety of pembrolizumab first-line monotherapy for HNSCC has been validated using real-world data.

2.
Gerontology ; 70(3): 269-278, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38219723

RESUMO

INTRODUCTION: In aging populations, the coexistence of multiple health comorbidities represents a significant challenge for clinicians and researchers. Leveraging advances in omics techniques to characterize these health conditions may provide insight into disease pathogenesis as well as reveal biomarkers for monitoring, prognostication, and diagnosis. Researchers have previously established the utility of big data approaches with respect to comprehensive health outcome measurements in younger populations, identifying protein markers that may provide significant health information with a single blood sample. METHODS: Here, we employed a similar approach in two cohorts of older adults, the Baltimore Longitudinal Study of Aging (mean age = 76.12 years) and InCHIANTI Study (mean age = 66.05 years), examining the relationship between levels of serum proteins and 5 key health outcomes: kidney function, fasting glucose, physical activity, lean body mass, and percent body fat. RESULTS: Correlations between proteins and health outcomes were primarily shared across both older adult cohorts. We further identified that most proteins associated with health outcomes in the older adult cohorts were not associated with the same outcomes in a prior study of a younger population. A subset of proteins, adiponectin, MIC-1, and NCAM-120, were associated with at least three health outcomes in both older adult cohorts but not in the previously published younger cohort, suggesting that they may represent plausible markers of general health in older adult populations. CONCLUSION: Taken together, these findings suggest that comprehensive protein health markers have utility in aging populations and are distinct from those identified in younger adults, indicating unique mechanisms of disease with aging.


Assuntos
Envelhecimento , Proteômica , Humanos , Idoso , Estudos Longitudinais , Composição Corporal , Avaliação de Resultados em Cuidados de Saúde
3.
Eur Arch Otorhinolaryngol ; 281(2): 985-993, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37917165

RESUMO

PURPOSE: To perform the first head-to-head comparative evaluation of patient education material for obstructive sleep apnoea generated by two artificial intelligence chatbots, ChatGPT and its primary rival Google Bard. METHODS: Fifty frequently asked questions on obstructive sleep apnoea in English were extracted from the patient information webpages of four major sleep organizations and categorized as input prompts. ChatGPT and Google Bard responses were selected and independently rated using the Patient Education Materials Assessment Tool-Printable (PEMAT-P) Auto-Scoring Form by two otolaryngologists, with a Fellowship of the Royal College of Surgeons (FRCS) and a special interest in sleep medicine and surgery. Responses were subjectively screened for any incorrect or dangerous information as a secondary outcome. The Flesch-Kincaid Calculator was used to evaluate the readability of responses for both ChatGPT and Google Bard. RESULTS: A total of 46 questions were curated and categorized into three domains: condition (n = 14), investigation (n = 9) and treatment (n = 23). Understandability scores for ChatGPT versus Google Bard on the various domains were as follows: condition 90.86% vs.76.32% (p < 0.001); investigation 89.94% vs. 71.67% (p < 0.001); treatment 90.78% vs.73.74% (p < 0.001). Actionability scores for ChatGPT versus Google Bard on the various domains were as follows: condition 77.14% vs. 51.43% (p < 0.001); investigation 72.22% vs. 54.44% (p = 0.05); treatment 73.04% vs. 54.78% (p = 0.002). The mean Flesch-Kincaid Grade Level for ChatGPT was 9.0 and Google Bard was 5.9. No incorrect or dangerous information was identified in any of the generated responses from both ChatGPT and Google Bard. CONCLUSION: Evaluation of ChatGPT and Google Bard patient education material for OSA indicates the former to offer superior information across several domains.


Assuntos
Apneia Obstrutiva do Sono , Cirurgiões , Humanos , Inteligência Artificial , Ferramenta de Busca , Educação de Pacientes como Assunto , Apneia Obstrutiva do Sono/terapia
4.
Eur Arch Otorhinolaryngol ; 281(4): 2137-2143, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38117307

RESUMO

PURPOSE: To conduct a comparative performance evaluation of GPT-3.5, GPT-4 and Google Bard in self-assessment questions at the level of the American Sleep Medicine Certification Board Exam. METHODS: A total of 301 text-based single-best-answer multiple choice questions with four answer options each, across 10 categories, were included in the study and transcribed as inputs for GPT-3.5, GPT-4 and Google Bard. The first output responses generated were selected and matched for answer accuracy against the gold-standard answer provided by the American Academy of Sleep Medicine for each question. A global score of 80% and above is required by human sleep medicine specialists to pass each exam category. RESULTS: GPT-4 successfully achieved the pass mark of 80% or above in five of the 10 exam categories, including the Normal Sleep and Variants Self-Assessment Exam (2021), Circadian Rhythm Sleep-Wake Disorders Self-Assessment Exam (2021), Insomnia Self-Assessment Exam (2022), Parasomnias Self-Assessment Exam (2022) and the Sleep-Related Movements Self-Assessment Exam (2023). GPT-4 demonstrated superior performance in all exam categories and achieved a higher overall score of 68.1% when compared against both GPT-3.5 (46.8%) and Google Bard (45.5%), which was statistically significant (p value < 0.001). There was no significant difference in the overall score performance between GPT-3.5 and Google Bard. CONCLUSIONS: Otolaryngologists and sleep medicine physicians have a crucial role through agile and robust research to ensure the next generation AI chatbots are built safely and responsibly.


Assuntos
Inteligência Artificial , Médicos , Humanos , Ferramenta de Busca , Certificação , Sono
5.
Clin Otolaryngol ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38766691

RESUMO

INTRODUCTION: To investigate factors influencing survival in head and neck squamous cell carcinoma of unknown primary (HNSCCUP). METHODS: A retrospective observational cohort study was conducted, over 5 years from January 2015, in UK Head and Neck centres, of consecutive adults undergoing 18F-Fluorodeoxyglucose-PET-CT within 3 months of diagnosis with metastatic cervical squamous cell carcinoma. Patients treated as HNSCCUP underwent survival analysis, stratified by neck dissection and/or radiotherapy to the ipsilateral neck, and by HPV status. RESULTS: Data were received from 57 centres for 965 patients, of whom 482 started treatment for HNSCCUP (65.7% HPV-positive, n = 282/429). Five-year overall survival (OS) for HPV-positive patients was 85.0% (95% CI 78.4-92.3) and 43.5% (95% CI 32.9-57.5) for HPV-negative. HPV-negative status was associated with worse OS, disease-free (DFS), and disease-specific (DSS) survival (all p < .0001 on log-rank test) but not local control (LC) (p = .16). Unilateral HPV-positive disease treated with surgery alone was associated with significantly worse DFS (p < .0001) and LC (p < .0001) compared to radiotherapy alone or combined modalities (5-year DFS: 24.9%, 82.3% and 94.3%; 5-year LC: 41.8%, 98.8% and 98.6%). OS was not significantly different (p = .16). Unilateral HPV-negative disease treated with surgery alone was associated with significantly worse LC (p = .017) (5-year LC: estimate unavailable, 93.3% and 96.6%, respectively). Small numbers with bilateral disease precluded meaningful sub-group analysis. CONCLUSIONS: HPV status is associated with variable management and outcomes in HNSCCUP. Unilateral neck disease is treated variably and associated with poorer outcomes when managed with surgery alone. The impact of diagnostic oropharyngeal surgery on primary site emergence, survival and functional outcomes is unestablished.

6.
J Transl Med ; 21(1): 753, 2023 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-37880788

RESUMO

BACKGROUND: The combination of nivolumab + relatlimab is superior to nivolumab alone in the treatment of naive patients and has activity in PD-1 refractory melanoma. We had previously observed a reduced expression of LAG3 in melanoma tissue from patients with type 2 diabetes. METHOD: To evaluate the impact of diabetes on oncological outcomes of patients with advanced melanoma treated with nivolumab plus the LAG3 inhibitor relatlimab we performed a retrospective multicenter study. RESULTS: Overall, 129 patients were included: 88 without diabetes before the treatment, 37 who were diagnosed with type 2 diabetes before the start of treatment, and 4 without diabetes before treatment who developed immune checkpoint inhibitor-induced diabetes (ICI-DM). PFS was 21.71 months (95% CI: 15.61-27.81) in patients without diabetes, 10.23 months (95% CI: 5.81-14.66) in patients with type 2 diabetes, and 50.85 months (95% CI: 23.04-78.65) in patients who developed ICI-DM. OS was 37.94 months (95% CI: 31.02-44.85) in patients without diabetes, 22.12 months (95% CI: 14.41-29.85) in those with type 2 diabetes and 57.64 months (95% CI: 42.29-72.99) in those who developed ICI-DM. Multivariate analysis showed that the presence of diabetes and LDH was correlated with OS and PFS. The mean OS was 64.63 months in subjects with low levels of glucose (< 137 mg/dl) and 36.27 months in those with high levels (hazard ratio 0.16, 95% CI: 0.04-0.58; p = 0.005). The patients whose glucose blood level increased after 3 months of treatment with nivolumab + relatinib compared to baseline (ratio of blood level at baseline/after 3 months > 1.5) had a worse prognosis than those whose glucose level had not increased. This result was observed also in subgroups treated either in first line or further lines. Patients who developed ICI-DM during the study period had better outcomes than the overall population and patients without diabetes. CONCLUSIONS: LAG3 inhibition for treating metastatic or unresectable melanoma has a reduced efficacy in patients with type 2 diabetes, possibly due to a low expression of LAG3 in tumor tissue. Higher level evidence should be obtained.


Assuntos
Diabetes Mellitus Tipo 2 , Melanoma , Humanos , Nivolumabe/uso terapêutico , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Melanoma/complicações , Melanoma/tratamento farmacológico , Melanoma/patologia , Glucose , Ipilimumab/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
7.
Eur Arch Otorhinolaryngol ; 280(10): 4597-4618, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37329358

RESUMO

BACKGROUND: Recurrent head and neck squamous cell carcinomas (HNSCC) are frequently managed with salvage surgery, but the impact these operations have on function and quality-of-life (QoL) is understudied. This review aimed to provide a quantitative and qualitative assessment of the functional and QoL effects of salvage surgical procedures. METHODS: Systematic review and meta-analysis were conducted of studies reporting QoL and function following salvage HNSCC resections. RESULTS: The search identified 415 articles and 34 were selected for inclusion. Pooled random effects analysis revealed long-term feeding and tracheostomy tube rates of 18% and 7%. Pooled long-term feeding tube rates in open oral and oropharyngeal, transoral robotic, total and partial laryngectomy surgeries were 41%, 25%, 11% and 4%. Eight studies used validated QoL questionnaires. CONCLUSIONS: Functional and QoL outcomes from salvage surgery are acceptable, but appear to be worse following open procedures. Prospective studies measuring changes over time are needed to assess these procedures impact on patient well-being.


Assuntos
Neoplasias de Cabeça e Pescoço , Terapia de Salvação , Carcinoma de Células Escamosas de Cabeça e Pescoço , Humanos , Neoplasias de Cabeça e Pescoço/cirurgia , Terapia de Salvação/métodos , Qualidade de Vida , Carcinoma de Células Escamosas de Cabeça e Pescoço/cirurgia , Recidiva Local de Neoplasia
8.
Eur Arch Otorhinolaryngol ; 280(8): 3861-3866, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37115324

RESUMO

PURPOSE: A total laryngectomy creates an alternate airway for gas exchange that bypasses the upper aerodigestive tract. The subsequent reduction in nasal airflow, and therefore, reduction in deposition of particles to the olfactory neuroepithelium leads to hyposmia or anosmia. The aim of this study was to assess the quality of life impairment conferred by anosmia following laryngectomy and identify any specific patient-related risk factors that are associated with poorer outcomes. METHODS: Consecutive patients with a total laryngectomy presenting for review at three tertiary head and neck services (in Australia, the United Kingdom and India) over a 12-month period were recruited. Patient demographic and clinical data were collected, and each subject completed the validated assessment of self-reported olfactory functioning and olfaction-related quality of life questionnaire (ASOF). Dichotomous comparisons were performed using the student's unpaired t-test for continuous variables (SRP), a chi-squared test for categorical variables, and a Kendall's tau-b for ordinal variables (SOC) to assess for a correlation with poorer questionnaire scores. RESULTS: A total of 66 laryngectomees (13.4% female; age 65.7 ± 8.6 years) were included in the study. The mean SRP score of the cohort was found to be 15.6 ± 7.4, while the mean ORQ score was noted to be 16.4 ± 8.1. No other specific risk factors associated with poorer quality of life were identified. CONCLUSION: A significant quality of life detriment from hyposmia is conferred following laryngectomy. Further research to assess treatment options and the patient population that would best benefit from these interventions is required.


Assuntos
Transtornos do Olfato , Olfato , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Masculino , Laringectomia/efeitos adversos , Anosmia/etiologia , Transtornos do Olfato/etiologia , Qualidade de Vida
9.
Anal Chem ; 94(20): 7339-7349, 2022 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-35549087

RESUMO

Large RNA including mRNA (mRNA) has emerged as an important new class of therapeutics. Recently, this has been demonstrated by two highly efficacious vaccines based on mRNA sequences encoding for a modified version of the SARS-CoV-2 spike protein. There is currently significant demand for the development of new and improved analytical methods for the characterization of large RNA including mRNA therapeutics. In this study, we have developed an automated, high-throughput workflow for the rapid characterization and direct sequence mapping of large RNA and mRNA therapeutics. Partial RNase digestions using RNase T1 immobilized on magnetic particles were performed in conjunction with high-resolution liquid chromatography-mass spectrometry analysis. Sequence mapping was performed using automated oligoribonucleotide annotation and identifications based on MS/MS spectra. Using this approach, a >80% sequence of coverage of a range of large RNAs and mRNA therapeutics including the SARS-CoV-2 spike protein was obtained in a single analysis. The analytical workflow, including automated sample preparation, can be completed within 90 min. The ability to rapidly identify, characterize, and sequence map large mRNA therapeutics with high sequence coverage provides important information for identity testing, sequence validation, and impurity analysis.


Assuntos
COVID-19 , Espectrometria de Massas em Tandem , COVID-19/terapia , Humanos , RNA/química , RNA Mensageiro/genética , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus , Espectrometria de Massas em Tandem/métodos
10.
Nature ; 534(7607): 341-6, 2016 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-27281222

RESUMO

Chronic myeloid leukaemia (CML) arises after transformation of a haemopoietic stem cell (HSC) by the protein-tyrosine kinase BCR-ABL. Direct inhibition of BCR-ABL kinase has revolutionized disease management, but fails to eradicate leukaemic stem cells (LSCs), which maintain CML. LSCs are independent of BCR-ABL for survival, providing a rationale for identifying and targeting kinase-independent pathways. Here we show--using proteomics, transcriptomics and network analyses--that in human LSCs, aberrantly expressed proteins, in both imatinib-responder and non-responder patients, are modulated in concert with p53 (also known as TP53) and c-MYC regulation. Perturbation of both p53 and c-MYC, and not BCR-ABL itself, leads to synergistic cell kill, differentiation, and near elimination of transplantable human LSCs in mice, while sparing normal HSCs. This unbiased systems approach targeting connected nodes exemplifies a novel precision medicine strategy providing evidence that LSCs can be eradicated.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Proteínas Proto-Oncogênicas c-myc/antagonistas & inibidores , Proteína Supressora de Tumor p53/antagonistas & inibidores , Acetamidas/farmacologia , Acetamidas/uso terapêutico , Animais , Antígenos CD34/metabolismo , Azepinas/farmacologia , Azepinas/uso terapêutico , Morte Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proteínas de Ligação a DNA/metabolismo , Feminino , Proteínas de Fusão bcr-abl/metabolismo , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Humanos , Mesilato de Imatinib/farmacologia , Mesilato de Imatinib/uso terapêutico , Imidazolinas/farmacologia , Imidazolinas/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Masculino , Camundongos , Proteínas de Neoplasias/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/transplante , Proteômica , Proteínas Proto-Oncogênicas c-myc/deficiência , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Reprodutibilidade dos Testes , Transdução de Sinais/efeitos dos fármacos , Transcriptoma , Proteína Supressora de Tumor p53/deficiência , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
11.
Sensors (Basel) ; 22(20)2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36298392

RESUMO

Advancements in lean premixed combustion have increased the efficiency and reduced the amount of greenhouse gas emissions, but they have led to increased noise emissions due to higher turbulence and mixing fluctuations. This study used an external sensor (microphone) to validate the simulation of the combustion noise of a confined space. An experimental facility with a laboratory-scale furnace was used to carry out the measurement, and the simulation of the confined flame noise was conducted in OpenFOAM. The simulation utilized the Partially Stirred Reactor (PaSR) and a hybrid computational aeroacoustics (CAA) approach using the large eddy simulation (LES)/the Ffwocs Williams-Hawkings (FWH) method. Additionally, unsteady Reynolds-averaged Navier-Stokes (URANS)/the FWH method was tested for a comparison with the LES prediction. A sensor which was placed outside the enclosure for ease of access was then used to validate the results of the numerical model. The sensor data agreed with the LES/FWH results including the amplitude and frequency of the primary combustion peak and the overall sound pressure level (OASPL). This suggested that a sensor which was placed outside the enclosure could serve as a validation tool for the simulation of the confined flames despite the sound reflections from the walls.

12.
Nucleic Acids Res ; 46(15): 7662-7674, 2018 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-29939287

RESUMO

The transcriptional regulator EVI1 has an essential role in early hematopoiesis and development. However, aberrantly high expression of EVI1 has potent oncogenic properties and confers poor prognosis and chemo-resistance in leukemia and solid tumors. To investigate to what extent EVI1 function might be regulated by post-translational modifications we carried out mass spectrometry- and antibody-based analyses and uncovered an ATM-mediated double phosphorylation of EVI1 at the carboxy-terminal S858/S860 SQS motif. In the presence of genotoxic stress EVI1-WT (SQS), but not site mutated EVI1-AQA was able to maintain transcriptional patterns and transformation potency, while under standard conditions carboxy-terminal mutation had no effect. Maintenance of hematopoietic progenitor cell clonogenic potential was profoundly impaired with EVI1-AQA compared with EVI1-WT, in particular in the presence of genotoxic stress. Exploring mechanistic events underlying these observations, we showed that after genotoxic stress EVI1-WT, but not EVI1-AQA increased its level of association with its functionally essential interaction partner CtBP1, implying a role for ATM in regulating EVI1 protein interactions via phosphorylation. This aspect of EVI1 regulation is therapeutically relevant, as chemotherapy-induced genotoxicity might detrimentally sustain EVI1 function via stress response mediated phosphorylation, and ATM-inhibition might be of specific targeted benefit in EVI1-overexpressing malignancies.


Assuntos
Oxirredutases do Álcool/genética , Proteínas Mutadas de Ataxia Telangiectasia/genética , Autorrenovação Celular/genética , Proteínas de Ligação a DNA/genética , Regulação Leucêmica da Expressão Gênica , Proteína do Locus do Complexo MDS1 e EVI1/genética , Doença Aguda , Oxirredutases do Álcool/metabolismo , Animais , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/metabolismo , Perfilação da Expressão Gênica , Células HEK293 , Humanos , Leucemia Mieloide/genética , Leucemia Mieloide/metabolismo , Leucemia Mieloide/patologia , Proteína do Locus do Complexo MDS1 e EVI1/química , Proteína do Locus do Complexo MDS1 e EVI1/metabolismo , Mutação , Fosforilação
13.
Phys Rev Lett ; 122(6): 061105, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30822066

RESUMO

The Hubble constant (H_{0}) estimated from the local Cepheid-supernova distance ladder is in 3-σ tension with the value extrapolated from cosmic microwave background (CMB) data assuming the standard cosmological model. Whether this tension represents new physics or systematic effects is the subject of intense debate. Here, we investigate how new, independent H_{0} estimates can arbitrate this tension, assessing whether the measurements are consistent with being derived from the same model using the posterior predictive distribution (PPD). We show that, with existing data, the inverse distance ladder formed from BOSS baryon acoustic oscillation measurements and the Pantheon supernova sample yields an H_{0} posterior near identical to the Planck CMB measurement. The observed local distance ladder value is a very unlikely draw from the resulting PPD. Turning to the future, we find that a sample of ∼50 binary neutron star "standard sirens" (detectable within the next decade) will be able to adjudicate between the local and CMB estimates.

14.
Appl Opt ; 58(14): 3950-3956, 2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-31158215

RESUMO

Temperature is an important parameter for characterizing chemical, physical, and flow processes occurring in combustion environments. Laser-induced breakdown is a process widely used to determine a material's elemental components and its composition, known as laser-induced breakdown spectroscopy (LIBS). The breakdown event, or more specifically the breakdown threshold, for a low-pressure gas strongly depends on density effects emanating in the likelihood for multiphoton and avalanche ionization. In this work, a comparison of thermometry techniques using laser-induced breakdown is made and an approach to perform simultaneous gas-phase thermometry on a shot-to-shot basis and spectroscopy is demonstrated by monitoring the moment in time the thermal plasma develops along the intensity gradient of a laser pulse. Breakdown thresholds are profiled along the height of a lean methane-air and partially combusting rich propane-air McKenna flame, and correlated to radiation and convection-corrected thermocouple readings.

15.
Langmuir ; 34(30): 8887-8897, 2018 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-29975548

RESUMO

The performance of devices containing colloidal quantum dot (CQD) films is strongly dependent on the surface chemistry of the CQDs they contain. Multistep surface treatments, which combine two or more strategies, are important for creating films with high carrier mobility that are well passivated against trap states and oxidation. Here, we examine the effect of a number of these surface treatments on PbS CQD films, including cation exchange to form PbS/CdS core/shell CQDs, and solid-state ligand-exchange treatments with Cl, Br, I, and 1,2-ethanedithiol (EDT) ligands. Using laboratory-based and synchrotron-radiation-excited X-ray photoelectron spectroscopy (XPS), we examine the compositions of the surface layer before and after treatment, and correlate this with the performance data and stability in air. We find that halide ion treatments may etch the CQD surfaces, with detrimental effects on the air stability and solar cell device performance caused by a reduction in the proportion of passivated surface sites. We show that films made up of PbS/CdS CQDs are particularly prone to this, suggesting Cd is more easily etched from the surface than Pb. However, by choosing a less aggressive ligand treatment, a good coverage of passivators on the surface can be achieved. We show that halide anions bind preferentially to surface Pb (rather than Cd). By isolating the part of XPS signal originating from the topmost surface layer of the CQD, we show that air stability is correlated with the total number of passivating agents (halide + EDT + Cd) at the surface.

16.
Proc Natl Acad Sci U S A ; 112(17): 5479-84, 2015 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-25847991

RESUMO

The glucocorticoid receptor (GR) is a member of the nuclear receptor superfamily, which controls programs regulating cell proliferation, differentiation, and apoptosis. We have identified an unexpected role for GR in mitosis. We discovered that specifically modified GR species accumulate at the mitotic spindle during mitosis in a distribution that overlaps with Aurora kinases. We found that Aurora A was required to mediate mitosis-driven GR phosphorylation, but not recruitment of GR to the spindle. GR was necessary for mitotic progression, with increased time to complete mitosis, frequency of mitotic aberrations, and death in mitosis observed following GR knockdown. Complementation studies revealed an essential role for the GR ligand-binding domain, but no clear requirement for ligand binding in regulating chromosome segregation. The GR N-terminal domain, and specifically phosphosites S203 and S211, were not required. Reduced GR expression results in a cell cycle phenotype, with isolated cells from mouse and human subjects showing changes in chromosome content over prolonged passage. Furthermore, GR haploinsufficient mice have an increased incidence of tumor formation, and, strikingly, these tumors are further depleted for GR, implying additional GR loss as a consequence of cell transformation. We identified reduced GR expression in a panel of human liver, lung, prostate, colon, and breast cancers. We therefore reveal an unexpected role for the GR in promoting accurate chromosome segregation during mitosis, which is causally linked to tumorigenesis, making GR an authentic tumor suppressor gene.


Assuntos
Transformação Celular Neoplásica/metabolismo , Segregação de Cromossomos , Regulação Neoplásica da Expressão Gênica , Neoplasias/metabolismo , Receptores de Glucocorticoides/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Humanos , Camundongos , Camundongos Mutantes , Mitose/genética , Neoplasias/genética , Neoplasias/patologia , Estrutura Terciária de Proteína , Receptores de Glucocorticoides/genética , Células Tumorais Cultivadas , Proteínas Supressoras de Tumor/genética
18.
Int J Cancer ; 138(12): 2984-92, 2016 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-26815306

RESUMO

Ovarian cancer (OC) has the highest mortality of all gynaecological cancers. Early diagnosis offers an approach to achieving better outcomes. We conducted a blinded-evaluation of prospectively collected preclinical serum from participants in the multimodal group of the United Kingdom Collaborative Trial of Ovarian Cancer Screening. Using isobaric tags (iTRAQ) we identified 90 proteins differentially expressed between OC cases and controls. A second targeted mass spectrometry analysis of twenty of these candidates identified Protein Z as a potential early detection biomarker for OC. This was further validated by ELISA analysis in 482 serial serum samples, from 80 individuals, 49 OC cases and 31 controls, spanning up to 7 years prior to diagnosis. Protein Z was significantly down-regulated up to 2 years pre-diagnosis (p = 0.000000411) in 8 of 19 Type I patients whilst in 5 Type II individuals, it was significantly up-regulated up to 4 years before diagnosis (p = 0.01). ROC curve analysis for CA-125 and CA-125 combined with Protein Z showed a statistically significant (p = 0.00033) increase in the AUC from 77 to 81% for Type I and a statistically significant (p= 0.00003) increase in the AUC from 76 to 82% for Type II. Protein Z is a novel independent early detection biomarker for Type I and Type II ovarian cancer; which can discriminate between both types. Protein Z also adds to CA-125 and potentially the Risk of Ovarian Cancer algorithm in the detection of both subtypes.


Assuntos
Biomarcadores Tumorais/sangue , Proteínas Sanguíneas/metabolismo , Neoplasias Epiteliais e Glandulares/diagnóstico , Neoplasias Ovarianas/diagnóstico , Idoso , Detecção Precoce de Câncer , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Epiteliais e Glandulares/sangue , Neoplasias Ovarianas/sangue , Curva ROC
19.
Nucleic Acids Res ; 42(19): 12249-60, 2014 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-25274738

RESUMO

Transcription of immediate early genes (IEGs) in response to extrinsic and intrinsic signals is tightly regulated at multiple stages. It is known that untranslated regions of the RNA can play a role in these processes. Here we show that THOC5, a member of the TREX (transcription/export) complex, plays a role in expression of only a subset of constitutively active genes, however transcriptome analysis reveals that more than 90% of IEG were not induced by serum in THOC5 depleted cells. Furthermore, THOC5 depletion does not influence the expression of the most rapidly induced IEGs, e.g. Fos and Jun. One group of THOC5 target genes, including Id1, Id3 and Wnt11 transcripts, were not released from chromatin in THOC5 depleted cells. Genes in another group, including Myc and Smad7 transcripts, were released with shortening of 3'UTR by alternative cleavage, and were spliced but export was impaired in THOC5 depleted cells. By interactome analysis using THOC5 as bait, we show that upon stimulation with serum THOC5 forms a complex with polyadenylation-specific factor 100 (CPSF100). THOC5 is required for recruitment of CPSF100 to 3'UTR of THOC5 target genes. These data suggest the presence of a novel mechanism for the control of IEG response by THOC5 via 3'end-processing.


Assuntos
Fator de Especificidade de Clivagem e Poliadenilação/metabolismo , Genes Precoces , Proteínas Nucleares/metabolismo , Processamento de Terminações 3' de RNA , Regiões 3' não Traduzidas , Animais , Linhagem Celular , Camundongos , Células NIH 3T3 , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Splicing de RNA , Proteína Smad7/genética , Proteína Smad7/metabolismo , Transcrição Gênica
20.
J Biol Chem ; 289(13): 8931-46, 2014 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-24488492

RESUMO

Glucocorticoids (GC) regulate cell fate and immune function. We identified the metastasis-promoting methyltransferase, metastasis-related methyltransferase 1 (WBSCR22/Merm1) as a novel glucocorticoid receptor (GR) regulator relevant to human disease. Merm1 binds the GR co-activator GRIP1 but not GR. Loss of Merm1 impaired both GR transactivation and transrepression by reducing GR recruitment to its binding sites. This was accompanied by loss of GR-dependent H3K4Me3 at a well characterized promoter. Inflammation promotes GC resistance, in part through the actions of TNFα and IFNγ. These cytokines suppressed Merm1 protein expression by driving ubiquitination of two conserved lysine residues. Restoration of Merm1 expression rescued GR transactivation. Cytokine suppression of Merm1 and of GR function was also seen in human lung explants. In addition, striking loss of Merm1 protein was observed in both inflammatory and neoplastic human lung pathologies. In conclusion, Merm1 is a novel regulator of chromatin structure affecting GR recruitment and function, contributing to loss of GC sensitivity in inflammation, with suppressed expression in pulmonary disease.


Assuntos
Neoplasias Pulmonares/metabolismo , Metiltransferases/metabolismo , Receptores de Glucocorticoides/metabolismo , Linfócitos B/efeitos dos fármacos , Linfócitos B/metabolismo , Brônquios/patologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular Tumoral , Montagem e Desmontagem da Cromatina/efeitos dos fármacos , Epitélio/efeitos dos fármacos , Epitélio/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glucocorticoides/metabolismo , Histonas/química , Histonas/metabolismo , Humanos , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , Interferon gama/farmacologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Lisina/metabolismo , Metilação/efeitos dos fármacos , Metiltransferases/química , Ligação Proteica , Proteínas Quinases/metabolismo , Estrutura Terciária de Proteína , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Glucocorticoides/genética , Transdução de Sinais/efeitos dos fármacos , Ativação Transcricional/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia , Ubiquitinação/efeitos dos fármacos
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