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1.
NPJ Precis Oncol ; 6(1): 13, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-35233056

RESUMEN

The NCI-MATCH was designed to characterize the efficacy of targeted therapies in histology-agnostic driver mutation-positive malignancies. Sub-protocols F and G were developed to evaluate the role of crizotinib in rare tumors that harbored either ALK or ROS1 rearrangements. Patients with malignancies that progressed following at least one prior systemic therapy were accrued to the NCI-MATCH for molecular profiling, and those with actionable ALK or ROS1 rearrangements were offered participation in sub-protocols F or G, respectively. There were five patients who enrolled on Arm F (ALK) and four patients on Arm G (ROS1). Few grade 3 or 4 toxicities were noted, including liver test abnormalities, and acute kidney injury. For sub-protocol F (ALK), the response rate was 50% (90% CI 9.8-90.2%) with one complete response among the 4 eligible patients. The median PFS was 3.8 months, and median OS was 4.3 months. For sub-protocol G (ROS1) the response rate was 25% (90% CI 1.3-75.1%). The median PFS was 4.3 months, and median OS 6.2 months. Data from 3 commercial vendors showed that the prevalence of ALK and ROS1 rearrangements in histologies other than non-small cell lung cancer and lymphoma was rare (0.1% and 0.4% respectively). We observed responses to crizotinib which met the primary endpoint for ALK fusions, albeit in a small number of patients. Despite the limited accrual, some of the patients with these oncogenic fusions can respond to crizotinib which may have a therapeutic role in this setting.

2.
Sci Rep ; 12(1): 1910, 2022 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-35115579

RESUMEN

Increasing the intensity to which high power laser pulses are focused has opened up new research possibilities, including promising new approaches to particle acceleration and phenomena such as high field quantum electrodynamics. Whilst the intensity achievable with a laser pulse of a given power can be increased via tighter focusing, the focal spot profile also plays an important role in the interaction physics. Here we show that the spatial-intensity distribution, and specifically the ratio of the intensity in the peak of the laser focal spot to the halo surrounding it, is important in the interaction of ultraintense laser pulses with solid targets. By comparing proton acceleration measurements from foil targets irradiated with by a near-diffraction-limited wavelength scale focal spot and larger F-number focusing, we find that this spatial-intensity contrast parameter strongly influences laser energy coupling to fast electrons. We find that for multi-petawatt pulses, spatial-intensity contrast is potentially as important as temporal-intensity contrast.

3.
Rev Sci Instrum ; 92(11): 113102, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34852528

RESUMEN

Accurate characterization of incident radiation is a fundamental challenge for diagnostic design. Herein, we present an efficient spectral analysis routine that is able to characterize multiple components within the spectral emission by analytically reducing the number of parameters. The technique is presented alongside the design of a hard x-ray linear absorption spectrometer using the example of multiple Boltzmann-like spectral distributions; however, it is generally applicable to all absorption based spectrometer designs and can be adapted to any incident spectral shape. This routine is demonstrated to be tolerable to experimental noise and suitable for real-time data processing at multi-Hz repetition rates.

5.
Sci Rep ; 10(1): 105, 2020 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-31919383

RESUMEN

The spatio-temporal and polarisation properties of intense light is important in wide-ranging topics at the forefront of extreme light-matter interactions, including ultrafast laser-driven particle acceleration, attosecond pulse generation, plasma photonics, high-field physics and laboratory astrophysics. Here, we experimentally demonstrate modifications to the polarisation and temporal properties of intense light measured at the rear of an ultrathin target foil irradiated by a relativistically intense laser pulse. The changes are shown to result from a superposition of coherent radiation, generated by a directly accelerated bipolar electron distribution, and the light transmitted due to the onset of relativistic self-induced transparency. Simulations show that the generated light has a high-order transverse electromagnetic mode structure in both the first and second laser harmonics that can evolve on intra-pulse time-scales. The mode structure and polarisation state vary with the interaction parameters, opening up the possibility of developing this approach to achieve dynamic control of structured light fields at ultrahigh intensities.

6.
Ann Oncol ; 30(11): 1821-1830, 2019 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-31504139

RESUMEN

BACKGROUND: The National Cancer Institute-Molecular Analysis for Therapy Choice (NCI-MATCH) is a national precision medicine study incorporating centralized genomic testing to direct refractory cancer patients to molecularly targeted treatment subprotocols. This treatment subprotocol was designed to screen for potential signals of efficacy of ado-trastuzumab emtansine (T-DM1) in HER2-amplified histologies other than breast and gastroesophageal tumors. METHODS: Eligible patients had HER2 amplification at a copy number (CN) >7 based on targeted next-generation sequencing (NGS) with a custom Oncomine AmpliSeq™ (ThermoFisher Scientific) panel. Patients with prior trastuzumab, pertuzumab or T-DM1 treatment were excluded. Patients received T-DM1 at 3.6 mg/kg i.v. every 3 weeks until toxicity or disease progression. Tumor assessments occurred every three cycles. The primary end point was centrally assessed objective response rate (ORR). Exploratory end points included correlating response with HER2 CN by NGS. The impact of co-occurring genomic alterations and PTEN loss by immunohistochemistry were also assessed. RESULTS: Thirty-eight patients were enrolled and 36 included in efficacy analysis. Median prior therapies in the metastatic setting was 3 (range 0-9; unknown in one patient). Median HER2 CN was 17 (range 7-139). Partial responses were observed in two (5.6%) patients: one mucoepidermoid carcinoma of parotid gland and one parotid gland squamous cell cancer. Seventeen patients (47%) had stable disease including 8/10 (80%) with ovarian and uterine carcinomas, with median duration of 4.6 months. The 6-month progression-free survival rate was 23.6% [90% confidence interval 14.2% to 39.2%]. Common toxicities included fatigue, anemia, fever and thrombocytopenia with no new safety signals. There was a trend for tumor shrinkage with higher levels of gene CN as determined by the NGS assay. CONCLUSION: T-DM1 was well tolerated. While this subprotocol did not meet the primary end point for ORR in this heavily pre-treated diverse patient population, clinical activity was seen in salivary gland tumors warranting further study in this tumor type in dedicated trials.


Asunto(s)
Ado-Trastuzumab Emtansina/uso terapéutico , Antineoplásicos Inmunológicos/uso terapéutico , Biomarcadores de Tumor/genética , Neoplasias/tratamiento farmacológico , Receptor ErbB-2/genética , Ado-Trastuzumab Emtansina/farmacología , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos Inmunológicos/farmacología , Resistencia a Antineoplásicos/genética , Femenino , Amplificación de Genes , Humanos , Persona de Mediana Edad , National Cancer Institute (U.S.) , Neoplasias/genética , Neoplasias/mortalidad , Neoplasias/patología , Medicina de Precisión/métodos , Supervivencia sin Progresión , Receptor ErbB-2/antagonistas & inhibidores , Estados Unidos/epidemiología
7.
Opt Express ; 27(4): 4416-4423, 2019 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-30876060

RESUMEN

We introduce a new approach to temporally resolve ultrafast micron-scale processes via the use of a multi-channel optical probe. We demonstrate that this technique enables highly precise time-resolved, two-dimensional spatial imaging of intense laser pulse propagation dynamics, plasma formation and laser beam filamentation within a single pulse over four distinct time frames. The design, development and optimization of the optical probe system is presented, as are representative experimental results from the first implementation of the multi-channel probe with a high-power laser pulse interaction with a helium gas jet target.

8.
Am J Surg ; 217(6): 1025-1029, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30879795

RESUMEN

BACKGROUND: Upstaging from DCIS to invasive ductal carcinoma varies widely from 0 to 59%. We aim to identify risk factors associated with upstaging in all DCIS patients and based on specific surgical intervention. METHODS: Patients with a pre-operative diagnosis of DCIS undergoing BCT or mastectomy were reviewed. Multivariable analysis was performed to identify risk factors for upstaging. RESULTS: In total, 623 patients had a preoperative diagnosis of DCIS. Upstaging occurred in 74 patients (12%) overall. There was no difference in upstaging rates between mastectomy and BCT (11% v 14% p = 0.27). Sentinel lymph node biopsy was positive in 4/212 patients (1%). Multivariable analysis revealed suspicion of microinvasion (OR 5.7 95%CI2.2-14.9), surgeon suspicion of invasive disease (OR 2.7, 95% CI 1.2-6.4) and larger size/multicentric/extensive tumor (OR 1.9 95% CI 1.1-3.4) increase risk of upstaging. CONCLUSIONS: Suspicion of microinvasion, surgeon suspicion, and tumor size can be used to help guide the use of sentinel lymph node biopsy. For patients without these high risk characteristics, it is hard to justify the use of concurrent SLN biopsy for patients who undergo BCT.


Asunto(s)
Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/patología , Carcinoma Intraductal no Infiltrante/patología , Mastectomía Radical , Mastectomía Segmentaria , Adulto , Anciano , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/cirugía , Carcinoma Ductal de Mama/diagnóstico , Carcinoma Ductal de Mama/cirugía , Carcinoma Intraductal no Infiltrante/diagnóstico , Carcinoma Intraductal no Infiltrante/cirugía , Femenino , Humanos , Persona de Mediana Edad , Invasividad Neoplásica , Estadificación de Neoplasias , Estudios Retrospectivos , Factores de Riesgo , Biopsia del Ganglio Linfático Centinela
9.
Sci Rep ; 8(1): 4525, 2018 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-29540743

RESUMEN

A key issue in realising the development of a number of applications of high-intensity lasers is the dynamics of the fast electrons produced and how to diagnose them. We report on measurements of fast electron transport in aluminium targets in the ultra-intense, short-pulse (<50 fs) regime using a high resolution temporally and spatially resolved optical probe. The measurements show a rapidly (≈0.5c) expanding region of Ohmic heating at the rear of the target, driven by lateral transport of the fast electron population inside the target. Simulations demonstrate that a broad angular distribution of fast electrons on the order of 60° is required, in conjunction with extensive recirculation of the electron population, in order to drive such lateral transport. These results provide fundamental new insight into fast electron dynamics driven by ultra-short laser pulses, which is an important regime for the development of laser-based radiation and particle sources.

10.
Nat Commun ; 9(1): 724, 2018 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-29463872

RESUMEN

The range of potential applications of compact laser-plasma ion sources motivates the development of new acceleration schemes to increase achievable ion energies and conversion efficiencies. Whilst the evolving nature of laser-plasma interactions can limit the effectiveness of individual acceleration mechanisms, it can also enable the development of hybrid schemes, allowing additional degrees of control on the properties of the resulting ion beam. Here we report on an experimental demonstration of efficient proton acceleration to energies exceeding 94 MeV via a hybrid scheme of radiation pressure-sheath acceleration in an ultrathin foil irradiated by a linearly polarised laser pulse. This occurs via a double-peaked electrostatic field structure, which, at an optimum foil thickness, is significantly enhanced by relativistic transparency and an associated jet of super-thermal electrons. The range of parameters over which this hybrid scenario occurs is discussed and implications for ion acceleration driven by next-generation, multi-petawatt laser facilities are explored.

11.
Sci Rep ; 7(1): 8347, 2017 08 21.
Artículo en Inglés | MEDLINE | ID: mdl-28827645

RESUMEN

The transport of hot, relativistic electrons produced by the interaction of an intense petawatt laser pulse with a solid has garnered interest due to its potential application in the development of innovative x-ray sources and ion-acceleration schemes. We report on spatially and temporally resolved measurements of megagauss magnetic fields at the rear of a 50-µm thick plastic target, irradiated by a multi-picosecond petawatt laser pulse at an incident intensity of ~1020 W/cm2. The pump-probe polarimetric measurements with micron-scale spatial resolution reveal the dynamics of the magnetic fields generated by the hot electron distribution at the target rear. An annular magnetic field profile was observed ~5 ps after the interaction, indicating a relatively smooth hot electron distribution at the rear-side of the plastic target. This is contrary to previous time-integrated measurements, which infer that such targets will produce highly structured hot electron transport. We measured large-scale filamentation of the hot electron distribution at the target rear only at later time-scales of ~10 ps, resulting in a commensurate large-scale filamentation of the magnetic field profile. Three-dimensional hybrid simulations corroborate our experimental observations and demonstrate a beam-like hot electron transport at initial time-scales that may be attributed to the local resistivity profile at the target rear.

12.
Med Eng Phys ; 38(9): 895-903, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27245749

RESUMEN

It is proposed that direct mechanical loading can impair dermal lymphatic function, contributing to the causal pathway of pressure ulcers. The present study aims to investigate the effects of loading on human dermal lymphatic vessels. Ten participants were recruited with ages ranging from 24 to 61 years. Participants had intradermal Indocyanine Green injections administrated between left finger digits. Fluorescence was imaged for 5min sequences with an infra-red camera prior to lymph vessel loading, immediately after axial loading (60mmHg) and following a recovery period. Image processing was employed to defined transient lymph packets and compare lymph function between each test phase. The results revealed that between 1-8 transient events (median=4) occurred at baseline, with a median velocity of 8.1mm/sec (range 4.1-20.1mm/sec). Immediately post-loading, there was a significant (p<0.05) reduction in velocity (median=6.4, range 2.2-13.5mm/sec), although the number of transient lymph packages varied between participants. During the recovery period the number (range 1-7) and velocity (recovery median=9.6mm/sec) of transient packets were largely restored to basal values. The present study revealed that some individuals present with impaired dermal lymphatic function immediately after uniaxial mechanical loading. More research is needed to investigate the effects of pressure and shear on lymphatic vessel patency.


Asunto(s)
Dermis/irrigación sanguínea , Vasos Linfáticos/fisiología , Vasoconstricción , Adulto , Fenómenos Biomecánicos , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Vasos Linfáticos/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Imagen Óptica , Soporte de Peso , Adulto Joven
13.
Phys Rev E ; 93: 043201, 2016 04.
Artículo en Inglés | MEDLINE | ID: mdl-27176413

RESUMEN

An analysis of an electron spectrometer used to characterize fast electrons generated by ultraintense (10^{20}Wcm^{-2}) laser interaction with a preformed plasma of scale length measured by shadowgraphy is presented. The effects of fringing magnetic fields on the electron spectral measurements and the accuracy of density scale-length measurements are evaluated. 2D EPOCH PIC code simulations are found to be in agreement with measurements of the electron energy spectra showing that laser filamentation in plasma preformed by a prepulse is important with longer plasma scale lengths (>8 µm).

14.
Phys Rev Lett ; 114(9): 095004, 2015 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-25793822

RESUMEN

Energy loss in the transport of a beam of relativistic electrons in warm dense aluminum is measured in the regime of ultrahigh electron beam current density over 2×10^{11} A/cm^{2} (time averaged). The samples are heated by shock compression. Comparing to undriven cold solid targets, the roles of the different initial resistivity and of the transient resistivity (upon target heating during electron transport) are directly observable in the experimental data, and are reproduced by a comprehensive set of simulations describing the hydrodynamics of the shock compression and electron beam generation and transport. We measured a 19% increase in electron resistive energy loss in warm dense compared to cold solid samples of identical areal mass.

15.
Rev Sci Instrum ; 86(12): 123302, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26724017

RESUMEN

The paper presents the calibration of Fuji BAS-TR image plate (IP) response to high energy carbon ions of different charge states by employing an intense laser-driven ion source, which allowed access to carbon energies up to 270 MeV. The calibration method consists of employing a Thomson parabola spectrometer to separate and spectrally resolve different ion species, and a slotted CR-39 solid state detector overlayed onto an image plate for an absolute calibration of the IP signal. An empirical response function was obtained which can be reasonably extrapolated to higher ion energies. The experimental data also show that the IP response is independent of ion charge states.

16.
Phys Rev Lett ; 113(18): 185001, 2014 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-25396375

RESUMEN

The influence of lattice-melt-induced resistivity gradients on the transport of mega-ampere currents of fast electrons in solids is investigated numerically and experimentally using laser-accelerated protons to induce isochoric heating. Tailoring the heating profile enables the resistive magnetic fields which strongly influence the current propagation to be manipulated. This tunable laser-driven process enables important fast electron beam properties, including the beam divergence, profile, and symmetry to be actively tailored, and without recourse to complex target manufacture.

17.
Br J Cancer ; 111(6): 1241-8, 2014 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-25117820

RESUMEN

BACKGROUND: Bevacizumab has broad anti-tumour activity, but substantial risk of hypertension. No reliable markers are available for predicting bevacizumab-induced hypertension. METHODS: A genome-wide association study (GWAS) was performed in the phase III bevacizumab-based adjuvant breast cancer trial, ECOG-5103, to evaluate for an association between genotypes and hypertension. GWAS was conducted in those who had experienced systolic blood pressure (SBP) >160 mm Hg during therapy using binary analysis and a cumulative dose model for the total exposure of bevacizumab. Common toxicity criteria (CTC) grade 3-5 hypertension was also assessed. Candidate SNP validation was performed in the randomised phase III trial, ECOG-2100. RESULTS: When using the phenotype of SBP>160 mm Hg, the most significant association in SV2C (rs6453204) approached and met genome-wide significance in the binary model (P=6.0 × 10(-8); OR=3.3) and in the cumulative dose model (P=4.7 × 10(-8); HR=2.2), respectively. Similar associations with rs6453204 were seen for CTC grade 3-5 hypertension but did not meet genome-wide significance. Validation study from ECOG-2100 demonstrated a statistically significant association between this SNP and grade 3/4 hypertension using the binary model (P-value=0.037; OR=2.4). CONCLUSIONS: A genetic variant in SV2C predicted clinically relevant bevacizumab-induced hypertension in two independent, randomised phase III trials.


Asunto(s)
Inhibidores de la Angiogénesis/efectos adversos , Anticuerpos Monoclonales Humanizados/efectos adversos , Neoplasias de la Mama/tratamiento farmacológico , Hipertensión/inducido químicamente , Hipertensión/genética , Glicoproteínas de Membrana/genética , Proteínas del Tejido Nervioso/genética , Inhibidores de la Angiogénesis/uso terapéutico , Anticuerpos Monoclonales Humanizados/uso terapéutico , Bevacizumab , Biomarcadores , Presión Sanguínea , Femenino , Estudio de Asociación del Genoma Completo , Genotipo , Humanos , Polimorfismo de Nucleótido Simple
18.
Rev Sci Instrum ; 85(3): 033304, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24689572

RESUMEN

A modification to the standard Thomson parabola spectrometer is discussed, which is designed to measure high energy (tens of MeV/nucleon), broad bandwidth spectra of multi-species ions accelerated by intense laser plasma interactions. It is proposed to implement a pair of extended, trapezoidal shaped electric plates, which will not only resolve ion traces at high energies, but will also retain the lower energy part of the spectrum. While a longer (along the axis of the undeflected ion beam direction) electric plate design provides effective charge state separation at the high energy end of the spectrum, the proposed new trapezoidal shape will enable the low energy ions to reach the detector, which would have been clipped or blocked by simply extending the rectangular plates to enhance the electrostatic deflection.

19.
Int J Clin Pract ; 68(8): 963-71, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24750544

RESUMEN

BACKGROUND: Many factors are associated with medication non-adherence in Parkinson's disease (PD), including complex treatment regimens, mood disorders and impaired cognition. However, interventions to improve adherence which acknowledge such factors are lacking. A phase II randomised controlled trial was conducted investigating whether Adherence Therapy (AT) improves medication adherence and quality of life (QoL) compared with routine care (RC) in PD. METHODS: Eligible PD patients and their spouse/carers were randomised to intervention (RC plus AT) or control (RC alone). Primary outcomes were change in adherence (Morisky Medication Adherence Scale) and QoL (Parkinson's Disease Questionnaire-39) from baseline to week-12 follow up. Secondary outcomes were MDS-UPDRS (part I, II, IV), Beliefs about Medication Questionnaire (BMQ), EuroQol (EQ-5D) and the Caregiving Distress Scale. Blinded data were analysed using logistic and linear regression models based on the intention-to-treat principle. RESULTS: Seventy-six patients and 46 spouse/carers completed the study (intervention: n = 38 patients, n = 24 spouse/carers). At week-12 AT significantly improved adherence compared with RC (OR 8.2; 95% CI: 2.8, 24.3). Numbers needed to treat (NNT) were 2.2 (CI: 1.6, 3.9). Compared with RC, AT significantly improved PDQ-39 (-9.0 CI: -12.2, -5.8), BMQ general harm (-1.0 CI: -1.9, -0.2) and MDS-UPDRS part II (-4.8 CI: -8.1, -1.4). No significant interaction was observed between the presence of a spouse/carer and the effect of AT. CONCLUSION: Adherence Therapy improved self-reported adherence and QoL in a PD sample. The small NNT suggests AT may be cost-effective. A larger pragmatic trial to test the efficacy and cost-effectiveness of AT by multiple therapists is required.


Asunto(s)
Actividades Cotidianas , Cumplimiento de la Medicación , Enfermedad de Parkinson/tratamiento farmacológico , Calidad de Vida , Anciano , Anciano de 80 o más Años , Análisis Costo-Beneficio , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/psicología , Encuestas y Cuestionarios
20.
Phys Rev Lett ; 111(9): 095001, 2013 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-24033041

RESUMEN

Fast electron transport in Si, driven by ultraintense laser pulses, is investigated experimentally and via 3D hybrid particle-in-cell simulations. A transition from a Gaussian-like to an annular fast electron beam profile is demonstrated and explained by resistively generated magnetic fields. The results highlight the potential to completely transform the beam transport pattern by tailoring the resistivity-temperature profile at temperatures as low as a few eV.

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