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1.
ACS Appl Mater Interfaces ; 16(27): 35333-35341, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38946070

RESUMO

Xenon (Xe) is a commercially valuable element found in trace amounts in the off-gas from used nuclear fuel. Recovering Xe from these streams provides a cost-effective means to increase its supply. However, achieving high-purity Xe recovery is challenging due to the need for separation from nearly identical krypton (Kr). Metal-organic frameworks (MOFs), a class of crystalline porous materials, show potential to separate Xe and Kr by utilizing differences in their kinetic diameters, allowing for selective separation. In this work, we study the impact of pore aperture and volume on selective Xe recovery using four robust aluminum MOFs: Al-PMOF, Al-PyrMOF, Al-BMOF and MIL-120, all with conserved structural topology. The pore topology in each MOF is dictated by the dimensions of the tetracarboxylate ligand employed, with larger ligands leading to MOFs with increased pore size and volume. Our experimental and computational investigations revealed that MIL-120 exhibits the highest affinity (21.94 kH(Xe) = 21.94 mmol g-1 bar-1) for Xe among all MOFs, while Al-BMOF demonstrates the highest Xe/Kr selectivity of 14.34. We evaluated the potential of both MIL-120 and Al-BMOF for Xe recovery through breakthrough analysis using a mixture of 400 ppm Xe:40 ppm Kr. Our results indicate that due to its larger pore volume, Al-BMOF captured more Xe than MIL-120, demonstrating superior Xe/Kr separation efficiency.

2.
Br J Cancer ; 117(6): 876-883, 2017 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-28809864

RESUMO

BACKGROUND: Following chemo-radiotherapy (CCRT) for human papilloma virus positive (HPV+) locally advanced head and neck cancer, patients frequently undergo unnecessary neck dissection (ND) and/or repeated biopsies for abnormal PET-CT, which causes significant morbidity. We assessed the role of circulating HPV DNA in identifying 'true' residual disease. METHODS: We prospectively recruited test (n=55) and validation (n=33) cohorts. HPV status was confirmed by E7 RT-PCR. We developed a novel amplicon-based next generation sequencing assay (HPV16-detect) to detect circulating HPV DNA. Circulating HPV DNA levels post-CCRT were correlated to disease response (PET-CT). RESULTS: In pre-CCRT plasma, HPV-detect demonstrated 100% sensitivity and 93% specificity, and 90% sensitivity and 100% specificity for the test (27 HPV+) and validation (20 HPV+) cohorts, respectively. Thirty-six out of 37 patients (test and validation cohort) with complete samples-set had negative HPV-detect at end of treatment. Six patients underwent ND (3) and repeat primary site biopsies (3) for positive PET-CT but had no viable tumour. One patient had positive HPV-detect and positive PET-CT and liver biopsy, indicating 100% agreement for HPV-detect and residual cancer. CONCLUSIONS: We demonstrate that HPV16-detect is a highly sensitive and specific test for identification of HPV DNA in plasma at diagnosis. HPV DNA post-treatment correlates with clinical response.


Assuntos
Carcinoma de Células Escamosas/sangue , Carcinoma de Células Escamosas/terapia , Quimiorradioterapia , DNA Viral/sangue , Neoplasias de Cabeça e Pescoço/sangue , Neoplasias de Cabeça e Pescoço/terapia , Papillomavirus Humano 16/genética , Carcinoma de Células Escamosas/patologia , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Neoplasias Hipofaríngeas/sangue , Neoplasias Hipofaríngeas/patologia , Neoplasias Hipofaríngeas/cirurgia , Neoplasias Laríngeas/sangue , Neoplasias Laríngeas/patologia , Neoplasias Laríngeas/terapia , Esvaziamento Cervical , Neoplasia Residual , Neoplasias Orofaríngeas/sangue , Neoplasias Orofaríngeas/patologia , Neoplasias Orofaríngeas/terapia , Estudos Prospectivos , Sensibilidade e Especificidade , Resultado do Tratamento
3.
Radiother Oncol ; 122(2): 207-211, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27393218

RESUMO

PURPOSE: This phase III, non-blinded, parallel-group, randomised controlled study evaluated the efficacy of Caphosol mouthwash in the management of radiation-induced oral mucositis (OM) in patients with head and neck cancer (HNC) undergoing radical (chemo)radiotherapy. PATIENTS AND METHODS: Eligible patients were randomised at 1:1 to Caphosol plus standard oral care (intervention) or standard oral care alone (control), stratified by radiotherapy technique and use of concomitant chemotherapy. Patients in the intervention arm used Caphosol for 7weeks: 6weeks during and 1-week post-radiotherapy. The primary endpoint was the incidence of severe OM (CTCAE ⩾grade 3) during and up to week 8 post-radiotherapy. Secondary endpoints include pharyngeal mucositis, dysphagia, pain and quality of life. RESULTS: The intervention (n=108) and control (n=107) arms were well balanced in terms of patient demographics and treatment characteristics. Following exclusion of patients with missing data, 210 patients were available for analysis. The incidence of severe OM did not differ between the intervention and control arms (64.1% versus 65.4%, p=0.839). Similarly, no significant benefit was observed for other secondary endpoints. Overall, compliance with the recommended frequency of Caphosol was low. CONCLUSION: Caphosol did not reduce the incidence or duration of severe OM during and after radiotherapy in HNC.


Assuntos
Neoplasias de Cabeça e Pescoço/radioterapia , Antissépticos Bucais/uso terapêutico , Lesões por Radiação/terapia , Estomatite/terapia , Adulto , Idoso , Feminino , Neoplasias de Cabeça e Pescoço/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Lesões por Radiação/epidemiologia , Estomatite/epidemiologia
4.
Br J Cancer ; 116(1): 28-35, 2017 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-27884018

RESUMO

BACKGROUND: Patients with head and neck squamous cell carcinoma (HNSCC) undergoing radical chemo-radiation (CRT) frequently receive transfusion with packed red cells (PRCT) during radiotherapy on the basis that PRCT increases tumour oxygenation and overcomes hypoxia-induced radio-resistance. This is likely to be a significant oversimplification given the fact that tumour hypoxia is the result of several intrinsic and extrinsic factors, including many that are not directly related to serum haemoglobin (Hb). Therefore, we have studied the effect of PRCT on tumour oxygenation in a prospective cohort of patients who developed low Hb during radical CRT for HNSCC. METHODS: This was a prospective study of 20 patients with HNSCC receiving radical CRT undergoing PRCT for Hb<11.5 g dl-1. Patients underwent pretransfusion and posttransfusion intrinsic susceptibility-weighted (SWI) MRI and dynamic contrast-enhanced (DCE) MRI. Blood samples were obtained at the time of MRI scanning and two further time points for measuring Hb and a panel of serum cytokine markers of tumour hypoxia. 3D T2* and Ktrans maps were calculated from the MRI data for primary tumours and cervical lymph node metastases. RESULTS: PRCT produced no change (11 patients) or reduced (1 patient) T2* (tumour oxygenation) in 12 of the 16 (75%) evaluable primary tumours. Three of the four patients with improved tumour oxygenation progressed or had partial response following treatment completion. There were variable changes in Ktrans (tumour perfusion or vessel permeability) following PRCT that were of small magnitude for most tumours. Pre- and Post-PRCT levels of measured cytokines were not significantly different. CONCLUSIONS: This study suggests that PRCT during radical CRT for HNSCC does not improve tumour oxygenation. Therefore, oncologists should consider changing practice according to NICE and American Association of Blood Banks guidelines on PRCT for anaemia.


Assuntos
Transfusão de Sangue , Carcinoma de Células Escamosas/terapia , Quimiorradioterapia , Neoplasias de Cabeça e Pescoço/terapia , Hipóxia Tumoral , Idoso , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/patologia , Feminino , Neoplasias de Cabeça e Pescoço/diagnóstico , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Estudos Longitudinais , Metástase Linfática , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Carcinoma de Células Escamosas de Cabeça e Pescoço , Hipóxia Tumoral/efeitos dos fármacos
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