In the PACIFIC trial, durvalumab significantly improved progression-free and overall survival (PFS/OS) versus placebo, with manageable safety, in unresectable, stage III non-small-cell lung cancer ...(NSCLC) patients without progression after chemoradiotherapy (CRT). We report exploratory analyses of outcomes by tumour cell (TC) programmed death-ligand 1 (PD-L1) expression.
Patients were randomly assigned (2:1) to intravenous durvalumab 10 mg/kg every 2 weeks or placebo ≤12 months, stratified by age, sex, and smoking history, but not PD-L1 status. Where available, pre-CRT samples were tested for PD-L1 expression (immunohistochemistry) and scored at pre-specified (25%) and post hoc (1%) TC cut-offs. Treatment-effect hazard ratios (HRs) were estimated from unstratified Cox proportional hazards models (Kaplan–Meier-estimated medians).
In total, 713 patients were randomly assigned, 709 of whom received at least 1 dose of study treatment durvalumab (n = 473) or placebo (n = 236). Some 451 (63%) were PD-L1-assessable: 35%, 65%, 67%, 33%, and 32% had TC ≥25%, <25%, ≥1%, <1%, and 1%–24%, respectively. As of 31 January 2019, median follow-up was 33.3 months. Durvalumab improved PFS versus placebo (primary-analysis data cut-off, 13 February 2017) across all subgroups HR, 95% confidence interval (CI); medians: TC ≥25% (0.41, 0.26–0.65; 17.8 versus 3.7 months), <25% (0.59, 0.43–0.82; 16.9 versus 6.9 months), ≥1% (0.46, 0.33–0.64; 17.8 versus 5.6 months), <1% (0.73, 0.48–1.11; 10.7 versus 5.6 months), 1%–24% 0.49, 0.30–0.80; not reached (NR) versus 9.0 months, and unknown (0.59, 0.42–0.83; 14.0 versus 6.4 months). Durvalumab improved OS across most subgroups (31 January 2019 data cut-off; HR, 95% CI; medians): TC ≥ 25% (0.50, 0.30–0.83; NR versus 21.1 months), <25% (0.89, 0.63–1.25; 39.7 versus 37.4 months), ≥1% (0.59, 0.41–0.83; NR versus 29.6 months), 1%–24% (0.67, 0.41–1.10; 43.3 versus 30.5 months), and unknown (0.60, 0.43–0.84; 44.2 versus 23.5 months), but not <1% (1.14, 0.71–1.84; 33.1 versus 45.6 months). Safety was similar across subgroups.
PFS benefit with durvalumab was observed across all subgroups, and OS benefit across all but TC <1%, for which limitations and wide HR CI preclude robust conclusions.
•Tumour tissue acquisition (pre-chemoradiotherapy) and tumour cell (TC) PD-L1 expression testing were not mandated.•However, outcomes were assessed based on PD-L1 expression in subgroups defined by pre-specified and post hoc TC cut-offs.•Treatment benefit with durvalumab, versus placebo, was observed irrespective of PD-L1 expression in terms of PFS.•OS improvement was demonstrated overall and across all subgroups, apart from the post hoc TC <1% subgroup.•Limitations (few events and baseline imbalances) and a wide CI for OS HR (includes 1) prevent robust conclusions for TC <1%.
Anilines are important feedstocks for pharmaceuticals, dyes, and other materials, but traditional approaches to their syntheses usually lack selectivity and environmental sustainability. Here, we ...describe the selective reduction of nitrobenzene to aniline under mild conditions, using water as the ultimate source of the required protons and electrons. We describe the electrochemical cell assembly, and detail steps for electrochemical reduction followed by organic extraction and analysis of the extracts using NMR.
For complete details on the use and execution of this protocol, please refer to Stergiou and Symes (2022a).
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•A protocol for the electrochemical reduction of nitrobenzene to aniline•The approach uses a polyoxometalate redox mediator to ensure high selectivity•The electrochemical setup and parameters are described in detail
Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics.
Anilines are important feedstocks for pharmaceuticals, dyes, and other materials, but traditional approaches to their syntheses usually lack selectivity and environmental sustainability. Here, we describe the selective reduction of nitrobenzene to aniline under mild conditions, using water as the ultimate source of the required protons and electrons. We describe the electrochemical cell assembly, and detail steps for electrochemical reduction followed by organic extraction and analysis of the extracts using NMR.
Anilines and substituted anilines are used on the multi-ton scale for producing polymers, pharmaceuticals, dyes, and other important compounds. Typically, these anilines are produced from their ...corresponding nitrobenzene precursors by reaction with hydrogen at high temperatures. However, this route suffers from a number of drawbacks, including the requirement to handle hydrogen gas, rather harsh reaction conditions that lead to a lack of selectivity and/or toleration of certain functional groups, and questionable environmental sustainability. In light of this, routes to the reduction of nitrobenzenes to their aniline derivatives that operate at room temperature, in aqueous solvent, and without the requirement to use harsh process conditions, hydrogen gas, or sacrificial reagents could be of tremendous benefit. Herein, we report on a highly selective electrocatalytic route for the reduction of nitrobenzenes to their corresponding anilines that works in aqueous solution at room temperature and which does not require the use of hydrogen gas or sacrificial reagents. The method uses a polyoxometalate redox mediator, which reversibly accepts electrons from the cathode and reacts with the nitrobenzenes in solution to reduce them to the corresponding anilines. A variety of substituted nitroarenes are explored as substrates, including those with potentially competing reducible groups and substrates that are difficult to reduce selectively by other means. In all cases, the selectivity for the redox-mediated route is higher than that for the direct reduction of the nitroarene substrates at the electrode, suggesting that redox-mediated electrochemical nitroarene reduction is a promising avenue for the more sustainable synthesis of substituted anilines.
Purpose:
To investigate the feasibility of three-dimensional (3D) dose measurements near thin high-Z materials placed in a water-like medium by using a polymer gel dosimeter (PGD) when the medium was ...irradiated with high energy photon beams.
Methods:
PGD is potentially a useful tool for this application because it can record the dose around a small object made of a high-Z material in a continuous 3D medium. In this study, the authors manufactured a methacrylic acid–based normoxic PGD, nMAG. Two 0.5 mm thick lead foils (1 × 1 cm) were placed in foil supports with 0.7 cm separation in a 1000 ml polystyrene container filled with nMAG. The authors used two foil configurations, i.e., orthogonal and parallel. In the orthogonal configuration, two foils were placed in the direction orthogonal to the beam axis. The parallel configuration had two foils arranged in parallel to the beam axis. The phantom was irradiated with an 18 MV photon beam of 5 × 5 cm field size. It was imaged with a three-Tesla (3 T) magnetic resonance imaging (MRI) scanned using the Car-Purcell-Meiboom-Gill pulse sequence. The spin–spin relaxation time (R2) to-dose calibration data were obtained by using small vials filled with nMAG and exposing to known doses. The DOSXYZnrc Monte Carlo (MC) code was used to get the expected dose distributions. More than 35 × 106 of histories were simulated so that the average error was less than 1%. An in-house matlab-based software was used to obtain the dose distributions from the measured R2 data as well as to compare the measurements and the MC predictions. The dose change due to the presence of the foils was studied by comparing the dose distributions with and without foils (or the reference).
Results:
For the orthogonal configuration, the measured dose along the beam axis showed an increase in the upstream side of the first foil, between the foils, and on the downstream side of the second foil. The range of increased dose area was 1.1 cm in the upstream of the first foil. However, in the downstream of the second foil, it was 0.2 cm, beyond which the dose fell below the reference dose by 10%. The dose profile between the foils showed a well-like shape with the minimum dose still larger than the reference dose by 1.8%. The minimum dose point was closer to the first foil than to the second foil. For the parallel configuration, the dose between foils was the largest at the center. The increased dose area opposite to the gap between foils extended outward to 1 cm. The spatial dose distributions of PGD and MC showed the same geometrical patterns except for the points inside the foils for both orthogonal and parallel foil arrangements.
Conclusions:
The authors demonstrated that the nMAG PGD with MRI could be used to measure the 3D dosimetric structures at the mm-scale in the vicinity of the foil. The current study provided more accurate 3D spatial dose distribution than the previous studies. Furthermore, the measurements were validated by the MC simulation.
With the advent of therapeutic radiation treatment machines with photon end point energies of several MeV, a new channel is available to transfer the photon energy to biological material, namely, ...pair production. This process has a photon threshold energy of 1.02 MeV. The probability of pair production, which depends on the square of the atomic number
(
Z
)
of the interacting material, increases markedly as the photon energy is further increased. As the goal of treatment planning in radiation therapy is to locally maximize the absorbed dose in abnormal cells and minimize the dose in surrounding normal cells, in this study the authors measured the dose enhancement which could be expected if a high-
Z
material such as gold was present adjacent to tumor sites during irradiation. The authors used photon beams produced by electron accelerators with energies ranging from 6 to 25 MV. They chose either gold or lead foils as high-
Z
materials, the measurements being repeated using the same geometry but replacing the high-
Z
materials with a low-
Z
material (aluminum). The comparison of the experimental results using low- and high-
Z
materials verified the theoretical prediction of the expected dose enhancement. The effect of finite range of the electron-positron pairs was also studied by varying the spacing between two foils placed parallel or orthogonal to the incident photon beam. Using an 18 MV photon beam, the authors observed a maximum dose enhancement of 44%. They intend therefore to proceed from these phantom studies to animal measurements.
The purpose of this study was to explore treatment options for aggression-related disorders. Two activities were examined to validate their use as frustration-reduction techniques --yoga and ...therapeutic drumming. Twenty-two college students were randomly assigned to participate in one of three groups--yoga, drumming, or silence (control)--following experimentally-induced frustration using a computerized Stroop color-word technique. Self-reported emotion levels and physiological responses were tracked at baseline, post-frustration, and post-treatment to measure responses to treatment. Results indicate that self-reported frustration levels were significantly reduced in all experimental groups, but physiologic responses showed no significant changes. A Multivariate Analysis of Variance (MANOVA) indicated no significant difference in lowered frustration for any of the treatment groups, suggesting that they are equally effective. These results also suggest that the passage of time may be key to successful emotion regulation. Further study should examine control variables and methodology to identify other factors that may be involved in regulating aggressive emotions.
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