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1.
Small ; 18(43): e2200177, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36026547

RESUMO

Hard carbon (HC) anodes together with ethylene carbonate (EC)-based electrolytes have shown significant promise for high-performing sodium-ion batteries. However, questions remain in relation to the initial contact between the carbon surface and the EC molecules. The surface of the HC anode is complex and can contain both flat pristine carbon surfaces, curvature, nanoscale roughness, and heteroatom defects. Combining density functional theory and experiments, the effect of different carbon surface motifs and defects on EC adsorption are probed, concluding that EC itself does not block any sodium storage sites. Nevertheless, the EC breakdown products do show strong adsorption on the same carbon surface motifs, indicating that the carbon surface defect sites can become occupied by the EC breakdown products, leading to competition between the sodium and EC fragments. Furthermore, it is shown that the EC fragments can react with a carbon vacancy or oxygen defect to give rise to CO2 formation and further oxygen functionalization of the carbon surface. Experimental characterization of two HC materials with different microstructure and defect concentrations further confirms that a significant concentration of oxygen-containing defects and disorder leads to a thicker solid electrolyte interphase, highlighting the significant effect of atomic-scale carbon structure on EC interaction.

2.
Chemistry ; 26(29): 6545-6553, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32142591

RESUMO

Graphite intercalation compounds (GICs) are often used to produce exfoliated or functionalised graphene related materials (GRMs) in a specific solvent. This study explores the formation of the Na-tetrahydrofuran (THF)-GIC and a new ternary system based on dimethylacetamide (DMAc). Detailed comparisons of in situ temperature dependent XRD with TGA-MS and Raman measurements reveal a series of dynamic transformations during heating. Surprisingly, the bulk of the intercalation compound is stable under ambient conditions, trapped between the graphene sheets. The heating process drives a reorganisation of the solvent and Na molecules, then an evaporation of the solvent; however, the solvent loss is arrested by restacking of the graphene layers, leading to trapped solvent bubbles. Eventually, the bubbles rupture, releasing the remaining solvent and creating expanded graphite. These trapped dopants may provide useful property enhancements, but also potentially confound measurements of grafting efficiency in liquid-phase covalent functionalization experiments on 2D materials.

3.
Cancer ; 120(2): 181-9, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24127364

RESUMO

BACKGROUND: The CO.20 trial randomized patients with K-RAS wild-type, chemotherapy-refractory, metastatic colorectal cancer to receive cetuximab (CET) plus brivanib alaninate (BRIV) or CET plus placebo (CET/placebo). METHODS: Quality of life (QoL) was assessed using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire C30 at baseline and at 2, 4, 6, 8, 12, 16, and 24 weeks until disease progression. Predefined coprimary QoL endpoints were time to deterioration (first worsening from baseline of ≥ 10 points) on the Physical Function (PF) and Global (GHS) scales. RESULTS: Of 750 randomized patients, 721 (358 of whom received CET/BRIV) were assessable for QoL. QoL compliance and baseline PF and GHS scores did not differ by treatment arm. The median time to deterioration was 1.6 months versus 1.1 months for GHS (P =.02) and 5.6 months versus 1.7 months for PF (P <.0001) favoring CET/placebo. Secondary analysis favored CET/placebo for QOL response on the PF, Cognitive Function, Fatigue, Nausea, Appetite, and Diarrhea scales. A greater percentage of patients on the CET/BRIV arm had PF worsening at 6 weeks (31% vs 17%). Clinical adverse events of ≥ grade 3 were more common with CET/BRIV than with CET/placebo, including fatigue (25% vs 11%), hypertension, rash, diarrhea, abdominal pain, dehydration, and anorexia. CONCLUSIONS: Compared with CET/placebo, the combination of CET/BRIV worsened time to QoL deterioration for patients with K-RAS wild-type, chemotherapy-refractory, metastatic colorectal cancer on the PF and GHS scales of European Organization for Research and Treatment of Cancer Quality of Life Questionnaire C30. This result may be due to higher rates of fatigue and gastrointestinal adverse events.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Qualidade de Vida , Alanina/administração & dosagem , Alanina/análogos & derivados , Anticorpos Monoclonais Humanizados/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cetuximab , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Diarreia/induzido quimicamente , Fadiga/induzido quimicamente , Genes ras , Humanos , Inquéritos e Questionários , Fatores de Tempo , Resultado do Tratamento , Triazinas/administração & dosagem
4.
Oncologist ; 18(7): 812-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23814044

RESUMO

BACKGROUND: This study aims to describe and compare health-related quality of life (HRQL) in patients with node-positive and high-risk node-negative HER2-positive early breast cancer receiving adjuvant docetaxel and trastuzumab-based or docetaxel-based regimens alone. METHODS: Eligible patients (n = 3,222) were randomly assigned to either four cycles of adjuvant doxorubicin and cyclophosphamide followed by four cycles of docetaxel (AC→T) or one of two trastuzumab-containing regimens: adjuvant doxorubicin and cyclophosphamide followed by docetaxel plus trastuzumab administered for 1 year (AC→TH) or six cycles of docetaxel plus carboplatin combined with trastuzumab administered for 1 year (TCH). The European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire C30 and BR-23 were administered at baseline, the start of cycle 4 (mid), and the end of chemotherapy (EOC), as well as at 6, 12, and 24 months after chemotherapy. RESULTS: Compliance rates for the EORTC questionnaires were acceptable at 72%-93% of eligible patients out to the 12-month assessment. Systemic side effect (SE) change scores were significantly improved for TCH-treated patients compared with AC→TH and AC→T at EOC, suggesting improved tolerability. Physical functioning (PF) was only slightly worse at midpoint for those receiving TCH, compared with patients who were just starting on taxane in an AC→TH regimen, but was otherwise similar between arms. All treatment arms recovered from the deterioration in SE, PF, and Global Health Scale scores by 1 year and median future perspective change scores continued to improve throughout treatment and follow-up. CONCLUSION: HRQL outcomes for adjuvant docetaxel and trastuzumab-based regimens are favorable and support TCH as a more tolerable treatment option.


Assuntos
Anticorpos Monoclonais Humanizados/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Taxoides/administração & dosagem , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/patologia , Carboplatina/administração & dosagem , Ciclofosfamida/administração & dosagem , Intervalo Livre de Doença , Docetaxel , Doxorrubicina/administração & dosagem , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Qualidade de Vida , Receptor ErbB-2/genética , Inquéritos e Questionários , Trastuzumab , Resultado do Tratamento
5.
Adv Mater ; 35(42): e2304091, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37501223

RESUMO

Emerging sodium-ion batteries (NIBs) and potassium-ion batteries (KIBs) show promise in complementing lithium-ion battery (LIB) technology and diversifying the battery market. Hard carbon is a potential anode candidate for LIBs, NIBs, and KIBs due to its high capacity, sustainability, wide availability, and stable physicochemical properties. Herein, a series of hard carbons is synthesized by hydrothermal carbonization and subsequent pyrolysis at different temperatures to finely tune their structural properties. When tested as anodes, the hard carbons exhibit differing ion-storage trends for Li, Na, and K, with NIBs achieving the highest reversible capacity. Extensive materials and electrochemical characterizations are carried out to study the correlation of structural features with electrochemical performance and to explain the specific mechanisms of alkali-ion storage in hard carbons. In addition, the best-performing hard carbon is tested against a sodium cathode Na3 V2 (PO4 )3 in a Na-ion pouch cell, displaying a high power density of 2172 W kg-1 at an energy density of 181.5 Wh kg-1 (based on the total weight of active materials in both anode and cathode). The Na-ion pouch cell also shows stable ultralong-term cycling (9000 h or 5142 cycles) and demonstrates the promising potential of such materials as sustainable, scalable anodes for beyond Li-batteries.

6.
J Clin Oncol ; 41(30): 4714-4720, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37847995

RESUMO

PURPOSE: Patients with advanced pancreatic cancer have a poor prognosis and there have been no improvements in survival since the introduction of gemcitabine in 1996. Pancreatic tumors often overexpress human epidermal growth factor receptor type 1 (HER1/EGFR) and this is associated with a worse prognosis. We studied the effects of adding the HER1/EGFR-targeted agent erlotinib to gemcitabine in patients with unresectable, locally advanced, or metastatic pancreatic cancer. PATIENTS AND METHODS: Patients were randomly assigned 1:1 to receive standard gemcitabine plus erlotinib (100 or 150 mg/d orally) or gemcitabine plus placebo in a double-blind, international phase III trial. The primary end point was overall survival. RESULTS: A total of 569 patients were randomly assigned. Overall survival based on an intent-to-treat analysis was significantly prolonged on the erlotinib/gemcitabine arm with a hazard ratio (HR) of 0.82 (95% CI, 0.69 to 0.99; P = .038, adjusted for stratification factors; median 6.24 months v 5.91 months). One-year survival was also greater with erlotinib plus gemcitabine (23% v 17%; P = .023). Progression-free survival was significantly longer with erlotinib plus gemcitabine with an estimated HR of 0.77 (95% CI, 0.64 to 0.92; P = .004). Objective response rates were not significantly different between the arms, although more patients on erlotinib had disease stabilization. There was a higher incidence of some adverse events with erlotinib plus gemcitabine, but most were grade 1 or 2. CONCLUSION: To our knowledge, this randomized phase III trial is the first to demonstrate statistically significantly improved survival in advanced pancreatic cancer by adding any agent to gemcitabine. The recommended dose of erlotinib with gemcitabine for this indication is 100 mg/d.

7.
Invest New Drugs ; 30(3): 1158-63, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21400081

RESUMO

PURPOSE: The Src family of kinases may play a role in the development and progression of gastric cancer. We evaluated the activity and safety of saracatinib an oral, anilinoquinazolone, non-receptor tyrosine kinase inhibitor targeting Src kinases, in patients with metastatic or locally advanced gastric carcinoma. METHODS: Eligible patients who had received ≤1 prior line of chemotherapy for metastatic disease received saracatinib 175 mg/day of a 28 day cycle until progression. The primary endpoint was the objective response and/or prolonged stable disease rate (pSD ≥ 16 weeks). RESULTS: Ten patients with gastric carcinoma and 11 with adenocarcinoma of the gastroesophageal junction received a median of 2 cycles (range 1-10 cycles) of treatment per patient. 17 patients were evaluable for response. No objective response was seen. One patient experienced prolonged Stable disease (pSD). Three patients had SD and 13 progressive disease. Median overall survival was 7.8 months (95% CI, 3.9-12.2 months) and median time to progression was 1.8 months (95% CI: 1.5-1.9 months). Grade 3 events possibly related to saracatinib included: fatigue (2 patients), hypoxia (2) anemia (3) and lymphopenia (2). CONCLUSION: Saracatinib has insufficient activity as a single agent in patients with advanced gastric adenocarcinoma to warrant further investigation. Further development in gastric cancer would require rational drug combinations or identification of a tumor phenotype sensitive to Src inhibition.


Assuntos
Adenocarcinoma/tratamento farmacológico , Benzodioxóis/uso terapêutico , Neoplasias Esofágicas/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Quinazolinas/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Esofágicas/patologia , Junção Esofagogástrica/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Neoplasias Gástricas/patologia , Quinases da Família src/antagonistas & inibidores
8.
Value Health ; 15(3): 580-5, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22583470

RESUMO

OBJECTIVE: Specific methodological challenges are often encountered during cancer-related economic evaluations. The objective of this study was to provide specific guidance to analysts on the methods for the conduct of high-quality economic evaluations in oncology by building on the Canadian Agency for Drugs and Technologies in Health Guidelines for the Economic Evaluation of Health Technologies (third edition). METHODS: Fifteen oncologists, health economists, health services researchers, and decision makers from across Canada identified sections in Canadian Agency for Drugs and Technologies in Health guidelines that would benefit from oncology-specific guidance. Fifteen sections of the guidelines were reviewed to determine whether 1) Canadian Agency for Drugs and Technologies in Health guidelines were sufficient for the conduct of oncology economic evaluations without further guidance specific for oncology products or 2) additional guidance was necessary. A scoping review was conducted by using a comprehensive and replicable search to identify relevant literature to inform recommendations. Recommendations were reviewed by representatives of academia, government, and the pharmaceutical industry in an iterative and formal review of the recommendations. RESULTS: Major adaptations for guidance related to time horizon, effectiveness, modeling, costs, and resources were required. Recommendations around the use of final outcomes over intermediate outcomes to calculate quality-adjusted life-years and life-years gained, the type of evidence, the source of evidence, and the use of time horizon and modeling were made. CONCLUSIONS: This article summarizes key recommendations for the conduct of economic evaluations in oncology and describes methods required to ensure that economic assessments in oncology are conducted in a standardized manner.


Assuntos
Guias como Assunto , Oncologia , Avaliação da Tecnologia Biomédica/economia , Canadá , Análise Custo-Benefício/normas
9.
Qual Life Res ; 21(5): 899-908, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21947690

RESUMO

PURPOSE: This paper reports relationships between symptoms assessed using a newly developed instrument for assessing patient-reported symptoms, the Modified Ambulatory Care Flow Sheet (MACFS), and other symptom assessment measures. METHODS: Using a cross-sectional design, patients on active treatment for colorectal cancer were recruited in an ambulatory setting of a tertiary care cancer center in western Canada. Participants completed the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire--Cancer 30, the Rotterdam Symptom Checklist Modified, Linear analog scales for pain and coping, and the MACFS, all at a single time point. RESULTS: We found moderate to strong correlations between the MACFS scores and scores on the other symptom measures used. The correlations were not as strong when using the MACFS symptom change scores, as when using the MACFS scores for the presence or absence of a particular symptom. CONCLUSIONS: The MACFS reflects the symptom experience of colorectal cancer patients. Further evaluation in more diverse populations and of the relationship between MACFS symptom scores and quality of life will improve our understanding of the MACFS and of the cancer patient treatment experience.


Assuntos
Assistência Ambulatorial/métodos , Indicadores Básicos de Saúde , Neoplasias/psicologia , Enfermagem Oncológica/métodos , Psicometria , Qualidade de Vida/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Alberta , Assistência Ambulatorial/psicologia , Lista de Checagem , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/enfermagem , Avaliação de Resultados em Cuidados de Saúde , Medição da Dor , Sistema de Registros , Reprodutibilidade dos Testes , Autorrelato , Estatística como Assunto , Inquéritos e Questionários , Adulto Jovem
10.
Can Fam Physician ; 58(9): e495-501, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22972740

RESUMO

OBJECTIVE: To identify factors associated with delays to medical assessment and diagnosis for patients with colorectal cancer (CRC). DESIGN: Data were collected through a standardized questionnaire. Clinical records were also reviewed. When necessary, patients were contacted by a member of the study team to collect missing data and confirm information. SETTING: Cross Cancer Institute in Edmonton, Alta. PARTICIPANTS: Patients newly diagnosed with a histologically proven colorectal adenocarcinoma were identified and eligible for the study. MAIN OUTCOME MEASURES: Associations between symptoms, tumour stage at operation, symptom duration, and tumour location were sought to identify factors associated with a delay in diagnosis of CRC. RESULTS: Surveys were completed by 93 patients. A total of 49% of patients had symptoms of CRC present for 1 month or less before seeing a physician, and 51% had symptoms for longer than 1 month. Seventy-five (86%) patients initially presented to family physicians for assessment, while 12 (14%) patients presented to the emergency department for their first physician encounters. Only 33 (38%) patients had digital rectal examinations during their first visits. Women were more likely to present to physicians with longer than 1 month of symptoms, while men were more likely to present with less than 1 month of symptoms (P = .03). Abdominal pain, blood in the stool, and change in stool size were the most frequent symptoms encountered. Twenty-two (26%) patients delayed seeking treatment because they thought their symptoms were not serious and 12 (14%) believed that their family physicians had taken inappropriate action. Fifteen (18%) patients attributed their delays to waiting too long for specialist referral and diagnostic tests. CONCLUSION: This study highlights the important role patients and physicians both play in delays in the diagnosis of CRC. Efforts to diminish future delays must focus on educating the public and practising physicians about important symptoms and signs of CRC. Additionally, the value of a digital rectal examination must be emphasized, along with continued promotion of CRC screening.


Assuntos
Adenocarcinoma/diagnóstico , Neoplasias Colorretais/diagnóstico , Diagnóstico Tardio/estatística & dados numéricos , Idoso , Alberta , Exame Retal Digital , Detecção Precoce de Câncer , Feminino , Pesquisas sobre Atenção à Saúde , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Encaminhamento e Consulta , Fatores de Risco , Inquéritos e Questionários , Fatores de Tempo , Listas de Espera
11.
J Mater Chem A Mater ; 10(37): 20121-20127, 2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36277421

RESUMO

Graphene-related materials are promising supports for electrocatalysts due to their stability and high surface area. Their innate surface chemistries can be controlled and tuned via functionalisation to improve the stability of both the carbon support and the metal catalyst. Functionalised graphenes were prepared using either aryl diazonium functionalisation or non-destructive chemical reduction, to provide groups adapted for platinum deposition. XPS and TGA-MS measurements confirmed the presence of polyethyleneglycol and sulfur-containing functional groups, and provided consistent values for the extent of the reactions. The deposited platinum nanoparticles obtained were consistently around 2 nm via reductive chemistry and around 4 nm via the diazonium route. Although these graphene-supported electrocatalysts provided a lower electrochemical surface area (ECSA), functionalised samples showed enhanced specific activity compared to a commercial platinum/carbon black system. Accelerated stress testing (AST) showed improved durability for the functionalised graphenes compared to the non-functionalised materials, attributed to edge passivation and catalyst particle anchoring.

12.
N Engl J Med ; 359(17): 1757-65, 2008 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-18946061

RESUMO

BACKGROUND: Treatment with cetuximab, a monoclonal antibody directed against the epidermal growth factor receptor, improves overall and progression-free survival and preserves the quality of life in patients with colorectal cancer that has not responded to chemotherapy. The mutation status of the K-ras gene in the tumor may affect the response to cetuximab and have treatment-independent prognostic value. METHODS: We analyzed tumor samples, obtained from 394 of 572 patients (68.9%) with colorectal cancer who were randomly assigned to receive cetuximab plus best supportive care or best supportive care alone, to look for activating mutations in exon 2 of the K-ras gene. We assessed whether the mutation status of the K-ras gene was associated with survival in the cetuximab and supportive-care groups. RESULTS: Of the tumors evaluated for K-ras mutations, 42.3% had at least one mutation in exon 2 of the gene. The effectiveness of cetuximab was significantly associated with K-ras mutation status (P=0.01 and P<0.001 for the interaction of K-ras mutation status with overall survival and progression-free survival, respectively). In patients with wild-type K-ras tumors, treatment with cetuximab as compared with supportive care alone significantly improved overall survival (median, 9.5 vs. 4.8 months; hazard ratio for death, 0.55; 95% confidence interval [CI], 0.41 to 0.74; P<0.001) and progression-free survival (median, 3.7 months vs. 1.9 months; hazard ratio for progression or death, 0.40; 95% CI, 0.30 to 0.54; P<0.001). Among patients with mutated K-ras tumors, there was no significant difference between those who were treated with cetuximab and those who received supportive care alone with respect to overall survival (hazard ratio, 0.98; P=0.89) or progression-free survival (hazard ratio, 0.99; P=0.96). In the group of patients receiving best supportive care alone, the mutation status of the K-ras gene was not significantly associated with overall survival (hazard ratio for death, 1.01; P=0.97). CONCLUSIONS: Patients with a colorectal tumor bearing mutated K-ras did not benefit from cetuximab, whereas patients with a tumor bearing wild-type K-ras did benefit from cetuximab. The mutation status of the K-ras gene had no influence on survival among patients treated with best supportive care alone. (ClinicalTrials.gov number, NCT00079066.)


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Receptores ErbB/imunologia , Genes ras , Mutação , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados , Cetuximab , Neoplasias Colorretais/genética , Neoplasias Colorretais/mortalidade , Análise Mutacional de DNA , Progressão da Doença , Receptores ErbB/antagonistas & inibidores , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Cuidados Paliativos , Qualidade de Vida
13.
Chem Sci ; 12(44): 14907-14919, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34820107

RESUMO

Here, the locus of functionalisation on graphene-related materials and the progress of the reaction is shown to depend strongly on the starting feedstock. Five characteristically different graphite sources were exfoliated and functionalized using a non-destructive chemical reduction method. These archetypical examples were compared via a model reaction, grafting dodecyl addends, evaluated with TGA-MS, XPS and Raman data. A general increase in grafting ratio (ranging from 1.1 wt% up to 25 wt%) and an improvement in grafting stoichiometry (C/R) were observed as flake radius decreased. Raman spectrum imaging of the functionalised natural flake graphite identified that grafting is directed towards flake edges. This behaviour was further corroborated, at atomistic resolution, by functionalising the graphene layers with bipyridine groups able to complex single platinum atoms. The distribution of these groups was then directly imaged using aberration-corrected HAADF-STEM. Platinum atoms were found to be homogeneously distributed across smaller graphenes; in contrast, a more heterogeneous distribution, with a predominance of edge grafting was observed for larger graphites. These observations show that grafting is directed towards flake edges, but not necessary at edge sites; the mechanism is attributed to the relative inaccessibility of the inner basal plane to reactive moieties, resulting in kinetically driven grafting nearer flake edges. This phenomenology may be relevant to a wide range of reactions on graphenes and other 2d materials.

14.
N Engl J Med ; 357(20): 2040-8, 2007 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-18003960

RESUMO

BACKGROUND: Cetuximab, an IgG1 chimeric monoclonal antibody against epidermal growth factor receptor (EGFR), has activity against colorectal cancers that express EGFR. METHODS: From December 2003 to August 2005, 572 patients who had colorectal cancer expressing immunohistochemically detectable EGFR and who had been previously treated with a fluoropyrimidine, irinotecan, and oxaliplatin or had contraindications to treatment with these drugs underwent randomization to an initial dose of 400 mg of cetuximab per square meter of body-surface area followed by a weekly infusion of 250 mg per square meter plus best supportive care (287 patients) or best supportive care alone (285 patients). The primary end point was overall survival. RESULTS: In comparison with best supportive care alone, cetuximab treatment was associated with a significant improvement in overall survival (hazard ratio for death, 0.77; 95% confidence interval [CI], 0.64 to 0.92; P=0.005) and in progression-free survival (hazard ratio for disease progression or death, 0.68; 95% CI, 0.57 to 0.80; P<0.001). These benefits were robust after adjustment in a multivariable Cox proportional-hazards model. The median overall survival was 6.1 months in the cetuximab group and 4.6 months in the group assigned to supportive care alone. Partial responses occurred in 23 patients (8.0%) in the cetuximab group but in none in the group assigned to supportive care alone (P<0.001); the disease was stable in an additional 31.4% of patients assigned to cetuximab and in 10.9% of patients assigned to supportive care alone (P<0.001). Quality of life was better preserved in the cetuximab group, with less deterioration in physical function and global health status scores (both P<0.05). Cetuximab treatment was associated with a characteristic rash; a rash of grade 2 or higher was strongly associated with improved survival (hazard ratio for death, 0.33; 95% CI, 0.22 to 0.50; P<0.001). The incidence of any adverse event of grade 3 or higher was 78.5% in the cetuximab group and 59.1% in the group assigned to supportive care alone (P<0.001). CONCLUSIONS: Cetuximab improves overall survival and progression-free survival and preserves quality-of-life measures in patients with colorectal cancer in whom other treatments have failed. (ClinicalTrials.gov number, NCT00079066 [ClinicalTrials.gov].).


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Receptores ErbB/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Humanizados , Antineoplásicos/efeitos adversos , Cetuximab , Neoplasias Colorretais/mortalidade , Exantema/induzido quimicamente , Feminino , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida
15.
Dalton Trans ; 49(30): 10308-10318, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32643711

RESUMO

Chemical functionalisation is one of the most active areas of graphene research, motivated by fundamental science, the opportunities to adjust or supplement intrinsic properties, and the need to assemble materials for a broad array of applications. Historically, the primary consideration has been the degree of functionalisation but there is growing interest in understanding how and where modification occurs. Reactions may proceed preferentially at edges, defects, or on graphitic faces; they may be correlated, uncorrelated, or anti-correlated with previously grafted sites. A detailed collation of existing literature data indicates that steric effects play a strong role in limiting the extent of reaction. However, the pattern of functionalisation may have important effects on the resulting properties. This article addresses the unifying principles of current graphene functionalisation technologies, with emphasis on understanding and controlling the locus of functionalisation.

16.
Nat Commun ; 11(1): 2083, 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32350276

RESUMO

Sodium-ion batteries are a promising battery technology for their cost and sustainability. This has led to increasing interest in the development of new sodium-ion batteries and new analytical methods to non-invasively, directly visualise battery chemistry. Here we report operando 1H and 23Na nuclear magnetic resonance spectroscopy and imaging experiments to observe the speciation and distribution of sodium in the electrode and electrolyte during sodiation and desodiation of hard carbon in a sodium metal cell and a sodium-ion full-cell configuration. The evolution of the hard carbon sodiation and subsequent formation and evolution of sodium dendrites, upon over-sodiation of the hard carbon, are observed and mapped by 23Na nuclear magnetic resonance spectroscopy and imaging, and their three-dimensional microstructure visualised by 1H magnetic resonance imaging. We also observe, for the first time, the formation of metallic sodium species on hard carbon upon first charge (formation) in a full-cell configuration.

17.
Breast Cancer Res Treat ; 114(3): 579-87, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18443903

RESUMO

PURPOSE: BCIRG 001 demonstrated prolonged disease-free (DFS) and overall survival (OS) but increased toxicity for adjuvant docetaxel, doxorubicin, and cyclophosphamide (TAC) versus 5-fluorouracil, doxorubicin, cyclophosphamide (FAC) in women with node positive breast cancer (BC). This study evaluates quality-adjusted survival and cost-effectiveness of adjuvant TAC versus FAC, taking downstream decisions and events into account, including palliative chemotherapy with taxanes. METHODS: We developed a Markov model for a cohort of women with node positive BC eligible for adjuvant anthracyclines. Data input included clinical and resource utilization data collected prospectively from BCIRG 001. Treatment decisions and outcomes with disease recurrence were based on a systematic literature review with validity reviewed by a national panel of Canadian BC oncologists. Direct costs for resource utilization following Canadian practice patterns were included. Unit costs were obtained from provincial cost list and published drug list prices. Utility scores were derived from the literature. An incremental cost-effectiveness ratio (ICER) in cost per quality-adjusted life-years (QALY) gained for TAC versus FAC was calculated. RESULTS: For 1,000 women with node positive BC, the model showed that TAC would lead to a gain of 313 QALY (370 life years) at an additional cost of $5.8 Million Canadian dollars (Cdn) compared to FAC, over a 10-year time horizon. The ICER of TAC versus FAC was $18,505.54 Cdn per QALY gained. Sensitivity analyses supported the robustness of the model. By one-way sensitivity analyses of over 50 model variables, 95% of the cumulative ICER variation was from $6,000 to $28,000 Cdn/QALY. By multivariate Monte Carlo simulation, there was a 70% probability that the ICER would be under $50,000 CdN/QALY. CONCLUSION: For women with node positive BC, TAC improves DFS and OS compared to FAC and is a cost-effective adjuvant chemotherapy strategy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/economia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/economia , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Taxoides/administração & dosagem , Quimioterapia Adjuvante/economia , Análise Custo-Benefício/economia , Docetaxel , Feminino , Humanos , Cadeias de Markov , Oncologia/economia , Oncologia/métodos , Método de Monte Carlo , Anos de Vida Ajustados por Qualidade de Vida , Recidiva , Resultado do Tratamento
18.
Clin Colorectal Cancer ; 7(2): 118-25, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18501071

RESUMO

PURPOSE: The aim of this study was to determine whether recommendations for surveillance carcinoembryonic antigen (CEA) testing in stage II/III colorectal cancer (CRC) are adhered to upon discharge from our cancer center, patterns of care after CEA elevation, and whether differences in outcomes exist between patients who did and did not receive recommended CEA monitoring. PATIENTS AND METHODS: A retrospective, single-institution chart review was completed at the Cross Cancer Institute (CCI) in Edmonton, Alberta. The Alberta Cancer Registry (ACR) identified patients with CRC diagnosed between January 1 and December 31, 2001. Patients with stage II/III CRC seen and/or treated at the CCI and later discharged to the community with follow-up recommendations based on American Society of Clinical Oncology guidelines were included. Carcinoembryonic antigen monitoring > or = every 4 months for > or = 2 years was deemed acceptable for study purposes. RESULTS: The ACR identified 152 stage II/III CRC cases meeting inclusion criteria. Eleven patients (7.2%) received the minimum predefined CEA follow-up. Eighty-seven CEA follow-up tests were elevated; only 20 (23%) elevated CEAs were investigated with predefined timely intervention. Twenty-six patients (17.1%) had documentable tumor recurrence. There was no difference in overall survival or time to recurrence between the groups who received and did not receive appropriate follow-up, although small numbers limit the effectiveness of statistical analysis. CONCLUSION: Post-therapy surveillance is important in CRC management. Our study reveals follow-up recommendations based on best available evidence for interval CEA testing are not followed in the community. These findings suggest the need for review of recommendations and change in management for monitoring discharged patients with stage II/III CRC.


Assuntos
Biomarcadores Tumorais/sangue , Antígeno Carcinoembrionário/sangue , Neoplasias Colorretais/imunologia , Recidiva Local de Neoplasia/prevenção & controle , Cooperação do Paciente , Vigilância da População , Características de Residência , Adulto , Idoso , Idoso de 80 Anos ou mais , Alberta/epidemiologia , Neoplasias Colorretais/terapia , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Guias de Prática Clínica como Assunto , Prognóstico , Encaminhamento e Consulta , Sistema de Registros , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
19.
Dis Colon Rectum ; 51(8): 1242-8, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18536970

RESUMO

PURPOSE: This study was designed to examine quality of life and fatigue in colorectal cancer survivors meeting and not meeting public health exercise guidelines. METHODS: A Canadian provincial cancer registry identified colorectal cancer survivors who were mailed a questionnaire that assessed self-reported exercise, quality of life (Functional Assessment of Cancer Therapy - Colorectal), fatigue, medical, and demographic variables. RESULTS: Completed questionnaires were received from 413 (61.3 percent) eligible colorectal cancer survivors. Only 25.9 percent of colorectal cancer survivors reported meeting exercise guidelines. Colorectal cancer survivors meeting public health exercise guidelines reported clinically and significantly better quality of life (mean difference, 6; 95 percent confidence interval, 2.3-9.8; P = 0.002) and fatigue (mean difference = 5.2; 95 percent confidence interval, 2.9-7.5; P < 0.001). Differences remained after adjusting for medical and demographic factors. Cancer site (i.e., colon vs. rectal) was the only variable to moderate this association (P < 0.05 for interaction). CONCLUSIONS: Colorectal cancer survivors meeting public health exercise guidelines reported significantly and meaningfully better quality of life and fatigue scores than colorectal cancer survivors who did not meet guidelines. Prospective observational studies and randomized, controlled trials are needed to further assess the causal nature of these relationships.


Assuntos
Neoplasias Colorretais/psicologia , Neoplasias Colorretais/reabilitação , Terapia por Exercício , Fadiga , Fidelidade a Diretrizes , Qualidade de Vida , Sobreviventes/psicologia , Idoso , Análise de Variância , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Inquéritos e Questionários
20.
Chem Sci ; 9(1): 209-217, 2018 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-29629089

RESUMO

A non-destructive and versatile chemical reduction method was used to dissolve and subsequently brominate few-layer graphene sheets (FLGs); the direct covalent attachment of bromine to the graphene framework was demonstrated by X-ray photoelectron spectroscopy (XPS). The brominated few-layer graphenes (FLG-Br) provide a convenient, stable, liquid-phase precursor, suitable for the synthesis of a variety of directly functionalised graphenes. As an example, the FLG-Br species was used to initiate atom transfer radical polymerisation (ATRP), to obtain poly(methyl methacrylate) (PMMA)-grafted graphene (FLG-PMMA), which was six times more dispersible in acetone than controls. In addition, the FLG-Br is active for nucleophilic substitution reactions, as illustrated by the preparation of methoxypolyethylene glycol (mPEG)- and OH-substituted derivatives. The products were characterised by thermogravimetric analysis coupled with mass spectrometry (TGA-MS), XPS and Raman spectroscopy. Grafting ratios (GR) for these polymer-grafted materials varied between 6 and 25%; even at these GRs, all graphene derivatives showed increased solubility in organic solvents.

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