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1.
Lancet Oncol ; 18(3): 357-370, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28163000

RESUMO

BACKGROUND: Peri-operative chemotherapy and surgery is a standard of care for patients with resectable oesophagogastric adenocarcinoma. Bevacizumab, a monoclonal antibody against VEGF, improves the proportion of patients responding to treatment in advanced gastric cancer. We aimed to assess the safety and efficacy of adding bevacizumab to peri-operative chemotherapy in patients with resectable gastric, oesophagogastric junction, or lower oesophageal adenocarcinoma. METHODS: In this multicentre, randomised, open-label phase 2-3 trial, we recruited patients aged 18 years and older with histologically proven, resectable oesophagogastric adenocarcinoma from 87 UK hospitals and cancer centres. We randomly assigned patients 1:1 to receive peri-operative epirubicin, cisplatin, and capecitabine chemotherapy or chemotherapy plus bevacizumab, in addition to surgery. Patients in the control group (chemotherapy alone) received three pre-operative and three post-operative cycles of epirubicin, cisplatin, and capecitabine chemotherapy: 50 mg/m2 epirubicin and 60 mg/m2 cisplatin on day 1 and 1250 mg/m2 oral capecitabine on days 1-21. Patients in the investigational group received the same treatment as the control group plus 7·5 mg/kg intravenous bevacizumab on day 1 of every cycle of chemotherapy and for six further doses once every 21 days following chemotherapy, as maintenance treatment. Randomisation was done by means of a telephone call to the Medical Research Council Clinical Trials Unit, where staff used a computer programme that implemented a minimisation algorithm with a random element to establish the allocation for the patient at the point of randomisation. Patients were stratified by chemotherapy centre, site of tumour, and tumour stage. The primary outcome for the phase 3 stage of the trial was overall survival (defined as the time from randomisation until death from any cause), analysed in the intention-to-treat population. Here, we report the primary analysis results of the trial; all patients have completed treatment and the required number of primary outcome events has been reached. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN 46020948, and with ClinicalTrials.gov, number NCT00450203. FINDINGS: Between Oct 31, 2007, and March 25, 2014, 1063 patients were enrolled and randomly assigned to receive chemotherapy alone (n=533) or chemotherapy plus bevacizumab (n=530). At the time of analysis, 508 deaths were recorded (248 in the chemotherapy alone group and 260 in the chemotherapy plus bevacizumab group). 3-year overall survival was 50·3% (95% CI 45·5-54·9) in the chemotherapy alone group and 48·1% (43·2-52·7) in the chemotherapy plus bevacizumab group (hazard ratio [HR] 1·08, 95% CI 0·91-1·29; p=0·36). Apart from neutropenia no other toxic effects were reported at grade 3 or worse severity in more than 10% of patients in either group. Wound healing complications were more prevalent in the bevacizumab group, occurring in 53 (12%) patients in this group compared with 33 (7%) patients in the chemotherapy alone group. In patients who underwent oesophagogastrectomy, post-operative anastomotic leak rates were higher in the chemotherapy plus bevacizumab group (23 [10%] of 233 in the chemotherapy alone group vs 52 [24%] of 220 in the chemotherapy plus bevacizumab group); therefore, recruitment of patients with lower oesophageal or junctional tumours planned for an oesophagogastric resection was stopped towards the end of the trial. Serious adverse events for all patients included anastomotic leaks (30 events in chemotherapy alone group vs 69 in the chemotherapy plus bevacizumab group), and infections with normal neutrophil count (42 events vs 53). INTERPRETATION: The results of this trial do not provide any evidence for the use of bevacizumab in combination with peri-operative epiribicin, cisplatin, and capecitabine chemotherapy for patients with resectable gastric, oesophagogastric junction, or lower oesophageal adenocarcinoma. Bevacizumab might also be associated with impaired wound healing. FUNDING: Cancer Research UK, MRC Clinical Trials Unit at University College London, and F Hoffmann-La Roche Limited.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Esofágicas/tratamento farmacológico , Junção Esofagogástrica/patologia , Neoplasias Gástricas/tratamento farmacológico , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Idoso , Bevacizumab/administração & dosagem , Capecitabina/administração & dosagem , Estudos de Casos e Controles , Cisplatino/administração & dosagem , Epirubicina/administração & dosagem , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/cirurgia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Assistência Perioperatória , Prognóstico , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia , Taxa de Sobrevida
2.
Inorg Chem ; 56(17): 10794-10814, 2017 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-28836774

RESUMO

We report a combined experimental and computational study of the synthesis and electronic structure of titanium borylimido compounds. Three new synthetic routes to this hitherto almost unknown class of Group 4 imide are presented. The double-deprotonation reaction of the borylamine H2NB(NAr'CH)2 (Ar' = 2,6-C6H3iPr2) with Ti(NMe2)2Cl2 gave Ti{NB(NAr'CH)2}Cl2(NHMe2)2, which was easily converted to Ti{NB(NAr'CH)2}Cl2(py)3. This compound is an entry point to other borylimides, for example, reacting with Li2N2pyrNMe to form Ti(N2pyrNMe){NB(NAr'CH)2}(py)2 and with 2 equiv of NaCp to give Cp2Ti{NB(NAr'CH)2}(py) (23). Borylamine-tert-butylimide exchange between H2NB(NAr'CH)2 and Cp*Ti(NtBu)Cl(py) under forcing conditions afforded Cp*Ti{NB(NAr'CH)2}Cl(py), which could be further substituted with guanidinate or pyrrolide-amine ligands to give Cp*Ti(hpp){NB(NAr'CH)2} (16) and Cp*Ti(NpyrNMe2){NB(NAr'CH)2} (17). The Ti-Nim distances in compounds with the NB(NAr'CH)2 ligand were comparable to those of the corresponding arylimides. Dialkyl- or diaryl-substituted borylamines do not undergo the analogous double-deprotonation or imide-amine exchange reactions. Reaction of (Cp″2Ti)2(µ2:η1,η1-N2) with N3BMes2 gave the base-free, diarylborylimide Cp″2Ti(NBMes2) (26) by an oxidative route; this compound has a relatively long Ti-Nim bond and large Cp″-Ti-Cp″ angle. Reaction of 16 with H2NtBu formed equilibrium mixtures with H2NB(NAr'CH)2 and Cp*Ti(hpp)(NtBu) (ΔrG = -1.0 kcal mol-1). In contrast, the dialkylborylimide Cp*Ti{MeC(NiPr)2}(NBC8H14) (2) reacted quantitatively with H2NtBu to give the corresponding tert-butylimide and borylamine. The electronic structures and imide-amine exchange reactions of half-sandwich and sandwich titanium borylimides have been evaluated using density functional theory (DFT), supported by quantum theory of atoms in molecules (QTAIM) and natural bond orbital (NBO) analysis, and placed more generally in context with the well-established alkyl- and arylimides and hydrazides. The calculations find that Ti-Nim bonds for borylimides are stronger and more covalent than in their organoimido or hydrazido analogues, and are strongest for alkyl- and arylborylimides. Borylamine-tert-butylimide exchange reactions fail for H2NBR2 (R = hydrocarbyl) but not for H2NB(NAr'CH)2 because the increased strength of the new Ti-Nim bond for the former is outweighed by the increased net H-N bond strengths in the borylamine. Variation of the Ti-Nim bond length over short distances is dominated by π-interactions with any appropriate orbital on the Nim atom organic substituent. However, over the full range of imides and hydrazides studied, overall bond energies do not correlate with bond length but with the Ti-Nim σ-bond character and the orthogonal π-interaction.

3.
J Am Chem Soc ; 137(32): 10140-3, 2015 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-26226513

RESUMO

Reaction of Ti(N2(iPr)N)(NNPh2)(py) with Ph(R)SiH2 (R = H, Ph) or 9-BBN gave reductive cleavage of the N(α)-N(ß) bond and formation of new silyl- or boryl-amido ligands. The corresponding reactions of Cp*Ti{MeC(N(i)Pr)2}(NNR2) (R = Me or Ph) with HBPin or 9-BBN gave borylhydrazido-hydride or borylimido products, respectively. N(α) and N(ß) atom transfer and dehydrogenative coupling reactions are also reported.

4.
Chemistry ; 19(21): 6840-4, 2013 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-23536394

RESUMO

Glycerol is converted to a mixture of butyric and isobutyric acid by rhodium- or iridium-catalysed carbonylation using HI as the co-catalyst. The initial reaction of glycerol with HI results in several intermediates that lead to isopropyl iodide, which upon carbonylation forms butyric and isobutyric acid. At low HI concentration, the intermediate allyl iodide undergoes carbonylation to give vinyl acetic acid and crotonic acid. Higher polyols C(n)H(n+2)(OH)(n) are carbonylated to the corresponding C(n+1) mono-carboxylic acids.


Assuntos
Ácidos Carboxílicos/química , Glicerol/química , Polímeros/química , Ácido Acético/química , Ácido Butírico/química , Catálise , Irídio/química , Isobutiratos/química , Estrutura Molecular , Oxirredução , Ródio/química
5.
Epidemics ; 42: 100662, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36563470

RESUMO

The COVID-19 pandemic has provided stiff challenges for planning and resourcing in health services in the UK and worldwide. Epidemiological models can provide simulations of how infectious disease might progress in a population given certain parameters. We adapted an agent-based model of COVID-19 to inform planning and decision-making within a healthcare setting, and created a software framework that automates processes for calibrating the model parameters to health data and allows the model to be run at national population scale on National Health Service (NHS) infrastructure. We developed a method for calibrating the model to three daily data streams (hospital admissions, intensive care occupancy, and deaths), and demonstrate that on cross-validation the model fits acceptably to unseen data streams including official estimates of COVID-19 incidence. Once calibrated, we use the model to simulate future scenarios of the spread of COVID-19 in England and show that the simulations provide useful projections of future COVID-19 clinical demand. These simulations were used to support operational planning in the NHS in England, and we present the example of the use of these simulations in projecting future clinical demand during the rollout of the national COVID-19 vaccination programme. Being able to investigate uncertainty and test sensitivities was particularly important to the operational planning team. This epidemiological model operates within an ecosystem of data technologies, drawing on a range of NHS, government and academic data sources, and provides results to strategists, planners and downstream data systems. We discuss the data resources that enabled this work and the data challenges that were faced.


Assuntos
COVID-19 , Humanos , Medicina Estatal , Pandemias , Vacinas contra COVID-19 , Calibragem , Ecossistema , Atenção à Saúde
6.
Arch Biochem Biophys ; 475(2): 115-20, 2008 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-18457652

RESUMO

A new class of carbamylating agents based on the cyclosulfamide scaffold is reported. These compounds were found to be efficient time-dependent inhibitors of human neutrophil elastase (HNE). Exploitation of the three sites of diversity present in the cyclosulfamide scaffold yielded compounds which inhibited HNE but not proteinase 3 (PR 3) or bovine trypsin. The findings reported herein suggest that the introduction of appropriate recognition elements into the cyclosulfamide scaffold may lead to highly selective agents of potential value in the design of activity-based probes suitable for investigating proteases associated with the pathogenesis of chronic obstructive pulmonary disease.


Assuntos
Desenho de Fármacos , Inibidores de Serina Proteinase/química , Inibidores de Serina Proteinase/farmacologia , Sulfonamidas/síntese química , Sulfonamidas/farmacologia , Ciclização , Humanos , Elastase de Leucócito/antagonistas & inibidores , Serina Endopeptidases/efeitos dos fármacos , Relação Estrutura-Atividade , Sulfonamidas/química , Fatores de Tempo
7.
Hum Gene Ther ; 22(3): 357-69, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21070114

RESUMO

ProSavin is an equine infectious anemia virus vector-based gene therapy for Parkinson's disease for which inducible HEK293T-based producer cell lines (PCLs) have been developed. These cell lines demonstrate stringent tetracycline-regulated expression of the packaging components and yield titers comparable to the established transient production system. A prerequisite for the use of PCL-derived lentiviral vectors (LVs) in clinical applications is the thorough characterization of both the LV and respective PCL with regard to identity and genetic stability. We describe the detailed characterization of two ProSavin PCLs (PS5.8 and PS46.2) and resultant ProSavin vector. The two cell lines demonstrate stable production of vector over a time period sufficient to allow generation of master and working cell banks, and subsequent large-scale vector production. ProSavin generated from the PCLs performs comparably in vivo to that produced by the standard transient transfection process with respect to transduction efficiency and immunogenicity. The development of ProSavin PCLs, and the detailed characterization described here, will aid the advancement of ProSavin for clinical application.


Assuntos
Terapia Genética , Vetores Genéticos/biossíntese , Microbiologia Industrial/métodos , Vírus da Anemia Infecciosa Equina/fisiologia , Doença de Parkinson/terapia , Animais , Encéfalo/metabolismo , Linhagem Celular , Dosagem de Genes , Vetores Genéticos/genética , Vetores Genéticos/imunologia , Instabilidade Genômica , Células HEK293 , Humanos , Vírus da Anemia Infecciosa Equina/genética , Vírus da Anemia Infecciosa Equina/imunologia , Vírus da Anemia Infecciosa Equina/isolamento & purificação , Masculino , Ratos , Ratos Wistar , Transcrição Gênica , Transdução Genética , Transgenes/genética
8.
J Oral Maxillofac Res ; 1(3): e4, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-24421974

RESUMO

OBJECTIVES: The aim of the current study was to investigate whether there was a relationship between a history of third molar removal and the prevalence of orofacial pain in a sample of the general population. MATERIAL AND METHODS: A survey was conducted in South East Cheshire, United Kingdom (81% participation rate). Information was collected using postal questionnaires (n = 1510) and dental records (n = 809). RESULTS: Participants who reported third molar extractions were more likely to report orofacial pain (RR = 1.29; 95% confidence interval [CI] 1.01 - 1.65). Participants with a more recent history of extractions (< 8 years ago) as recorded in dental records were more likely to report orofacial pain compared to those who had all third molar present (RR = 1.91; 95% CI 1.10 - 3.32). CONCLUSIONS: This research suggests that self-reported third molar removal is linked to self-reported orofacial pain, however evidence from one study is not sufficient to give an unequivocal answer.

9.
Invest Ophthalmol Vis Sci ; 51(6): 3291-9, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20107169

RESUMO

PURPOSE: Neovascularization occurs in response to tissue ischemia and growth factor stimulation. In ischemic retinopathies, however, new vessels fail to restore the hypoxic tissue; instead, they infiltrate the transparent vitreous. In a model of oxygen-induced retinopathy (OIR), TNFalpha and iNOS, upregulated in response to tissue ischemia, are cytotoxic and inhibit vascular repair. The aim of this study was to investigate the mechanism for this effect. METHODS: Wild-type C57/BL6 (WT) and TNFalpha(-/-) mice were subjected to OIR by exposure to 75% oxygen (postnatal days 7-12). The retinas were removed during the hypoxic phase of the model. Retinal cell death was determined by TUNEL staining, and the microglial cells were quantified after Z-series capture with a confocal microscope. In situ peroxynitrite and superoxide were measured by using the fluorescent dyes DCF and DHE. iNOS, nitrotyrosine, and arginase were analyzed by real-time PCR, Western blot analysis, and activity determined by radiolabeled arginine conversion. Astrocyte coverage was examined after GFAP immunostaining. RESULTS: The TNFalpha(-/-) animals displayed a significant reduction in TUNEL-positive apoptotic cells in the inner nuclear layer of the avascular retina compared with that in the WT control mice. The reduction coincided with enhanced astrocytic survival and an increase in microglial cells actively engaged in phagocytosing apoptotic debris that displayed low ROS, RNS, and NO production and high arginase activity. CONCLUSIONS: Collectively, the results suggest that improved vascular recovery in the absence of TNFalpha is associated with enhanced astrocyte survival and that both phenomena are dependent on preservation of microglial cells that display an anti-inflammatory phenotype during the early ischemic phase of OIR.


Assuntos
Isquemia/metabolismo , Microglia/citologia , Estresse Oxidativo , Doenças Retinianas/metabolismo , Neurônios Retinianos/patologia , Vasos Retinianos/metabolismo , Fator de Necrose Tumoral alfa/fisiologia , Animais , Apoptose , Arginase/metabolismo , Western Blotting , Contagem de Células , Morte Celular , Sobrevivência Celular , Marcação In Situ das Extremidades Cortadas , Isquemia/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Óxido Nítrico Sintase Tipo II/metabolismo , Nitrosação , Oxigênio/toxicidade , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Doenças Retinianas/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tirosina/análogos & derivados , Tirosina/metabolismo
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