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1.
Eur J Cancer ; 202: 114021, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38520925

RESUMEN

BACKGROUND: In the Netherlands, use of neoadjuvant radiotherapy for rectal cancer declined after guideline revision in 2014. This decline is thought to affect the clinical nature and treatability of locally recurrent rectal cancer (LRRC). Therefore, this study compared two national cross-sectional cohorts before and after the guideline revision with the aim to determine the changes in treatment and survival of LRRC patients over time. METHODS: Patients who underwent resection of primary rectal cancer in 2011 (n = 2094) and 2016 (n = 2855) from two nationwide cohorts with a 4-year follow up were included. Main outcomes included time to LRRC, synchronous metastases at time of LRRC diagnosis, intention of treatment and 2-year overall survival after LRRC. RESULTS: Use of neoadjuvant (chemo)radiotherapy for the primary tumour decreased from 88.5% to 60.0% from 2011 to 2016. The 3-year LRRC rate was not significantly different with 5.1% in 2011 (n = 114, median time to LRRC 16 months) and 6.3% in 2016 (n = 202, median time to LRRC 16 months). Synchronous metastasis rate did not significantly differ (27.2% vs 33.7%, p = 0.257). Treatment intent of the LRRC shifted towards more curative treatment (30.4% vs. 47.0%, p = 0.009). In the curatively treated group, two-year overall survival after LRRC diagnoses increased from 47.5% to 78.7% (p = 0.013). CONCLUSION: Primary rectal cancer patients in 2016 were treated less often with neoadjuvant (chemo)radiotherapy, while LRRC rates remained similar. Those who developed LRRC were more often candidate for curative intent treatment compared to the 2011 cohort, and survival after curative intent treatment also improved substantially.


Asunto(s)
Recurrencia Local de Neoplasia , Neoplasias del Recto , Humanos , Estudios Transversales , Recurrencia Local de Neoplasia/patología , Neoplasias del Recto/terapia , Neoplasias del Recto/patología , Terapia Combinada , Terapia Neoadyuvante , Estudios Retrospectivos
2.
Science ; 383(6687): 1118-1122, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38359104

RESUMEN

Attosecond-pump/attosecond-probe experiments have long been sought as the most straightforward method for observing electron dynamics in real time. Although there has been much success with overlapped near-infrared femtosecond and extreme ultraviolet attosecond pulses combined with theory, true attosecond-pump/attosecond-probe experiments have been limited. We used a synchronized attosecond x-ray pulse pair from an x-ray free-electron laser to study the electronic response to valence ionization in liquid water through all x-ray attosecond transient absorption spectroscopy (AX-ATAS). Our analysis showed that the AX-ATAS response is confined to the subfemtosecond timescale, eliminating any hydrogen atom motion and demonstrating experimentally that the 1b1 splitting in the x-ray emission spectrum is related to dynamics and is not evidence of two structural motifs in ambient liquid water.

3.
J Synchrotron Radiat ; 27(Pt 4): 890-901, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33565997

RESUMEN

Experiments using a THz pump and an X-ray probe at an X-ray free-electron laser (XFEL) facility like the Linac Coherent Light Source II (LCLS II) require frequency-tunable (3 to 20 THz), narrow bandwidth (∼10%), carrier-envelope-phase-stable THz pulses that produce high fields (>1 MV cm-1) at the repetition rate of the X-rays and are well synchronized with them. In this paper, a two-bunch scheme to generate THz radiation at LCLS II is studied: the first bunch produces THz radiation in an electromagnet wiggler immediately following the LCLS II undulator that produces X-rays from the second bunch. The initial time delay between the two bunches is optimized to compensate for the path difference in THz transport. The two-bunch beam dynamics, the THz wiggler and radiation are described, as well as the transport system bringing the THz pulses from the wiggler to the experimental hall.

4.
Br J Surg ; 106(12): 1632-1639, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31593294

RESUMEN

BACKGROUND: Marking the axilla with radioactive iodine seed and sentinel lymph node (SLN) biopsy have been proposed for axillary staging after neoadjuvant systemic therapy in clinically node-positive breast cancer. This study evaluated the identification rate and detection of residual disease with combined excision of pretreatment-positive marked lymph nodes (MLNs) together with SLNs. METHODS: This was a multicentre retrospective analysis of patients with clinically node-positive breast cancer undergoing neoadjuvant systemic therapy and the combination procedure (with or without axillary lymph node dissection). The identification rate and detection of axillary residual disease were calculated for the combination procedure, and for MLNs and SLNs separately. RESULTS: At least one MLN and/or SLN(s) were identified by the combination procedure in 138 of 139 patients (identification rate 99·3 per cent). The identification rate was 92·8 per cent for MLNs alone and 87·8 per cent for SLNs alone. In 88 of 139 patients (63·3 per cent) residual axillary disease was detected by the combination procedure. Residual disease was shown only in the MLN in 20 of 88 patients (23 per cent) and only in the SLN in ten of 88 (11 per cent), whereas both the MLN and SLN contained residual disease in the remainder (58 of 88, 66 per cent). CONCLUSION: Excision of the pretreatment-positive MLN together with SLNs after neoadjuvant systemic therapy in patients with clinically node-positive disease resulted in a higher identification rate and improved detection of residual axillary disease.


ANTECEDENTES: En el cáncer de mama con ganglios positivos clínicamente tras el tratamiento neoadyuvante sistémico, se ha propuesto la utilización de iodo radioactivo (Marking Axilla with Radioactive Iodine, MARI) y de la biopsia de ganglio linfático centinela para la estadificación axilar. En este estudio se evaluó la tasa de identificación y detección de enfermedad residual cuando se combinó la exéresis de los ganglios linfáticos marcados antes del tratamiento (marked lymph nodes, MLN) junto con los ganglios centinela (sentinel lymph nodes, SLN). MÉTODOS: Se realizó un análisis retrospectivo multicéntrico de pacientes con cáncer de mama con ganglios positivos clínicamente que se sometieron a tratamiento neoadyuvante sistémico y en las que se combinaron ambas técnicas (con o sin disección axilar). Se calcularon las tasas de identificación y detección de enfermedad residual axilar para MLN y SLN por separado y en conjunto. RESULTADOS: En 138/139 pacientes se identificaron ≥ 1 MLN y/o SLN combinando ambas técnicas (tasa de identificación del 99,3%). La tasa de identificación fue de 92,8% para MLN y del 87,8% para SLN. Combinando ambas técnicas se detectó enfermedad axilar residual en 88/139 (63,3%) pacientes. Se detectó enfermedad residual en 20/88 (22,7%) pacientes utilizando únicamente MLN, en 10/88 (11,4%) pacientes utilizando únicamente SLN y en 58/88 (65,9%) combinando ambas técnicas. CONCLUSIÓN: La exéresis conjunta de los ganglios marcados con iodo radioactivo antes del tratamiento neoadyuvante sistémico y de los ganglios centinela después del tratamiento en pacientes con cN+ logró una tasa de identificación más alta y una mejor detección de la enfermedad axilar residual.


Asunto(s)
Axila/patología , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Escisión del Ganglio Linfático/métodos , Ganglios Linfáticos/patología , Ganglio Linfático Centinela/patología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Ganglios Linfáticos/cirugía , Metástasis Linfática , Persona de Mediana Edad , Terapia Neoadyuvante , Estadificación de Neoplasias , Radioterapia Adyuvante , Estudios Retrospectivos , Ganglio Linfático Centinela/cirugía , Biopsia del Ganglio Linfático Centinela
5.
Diagn Interv Imaging ; 100(2): 77-83, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30262172

RESUMEN

OBJECTIVE: The purpose of this study was to retrospectively evaluate the safety and efficacy of posterior transperineal drainage in patients with presacral abscess. MATERIALS AND METHOD: The records of 21 patients (14 men, 7 women; mean age: 62.1±10 years) who underwent posterior transperineal drainage for the treatment of presacral abscess, either using fluoroscopy or computed tomography guidance, were retrospectively reviewed. Data were analysed with respect to technical success, tolerance, duration of drainage, complications and short-term outcome. RESULTS: A total of 28 posterior transperineal drainage procedures of presacral abscesses were performed in 21 patients, either using fluoroscopy (24/28; 86%) or computed tomography (4/28; 14%) guidance. Technical success rate was 89% (25/28 procedures) and clinical success rate 88% (22/25 technically successful procedures). Transperineal catheter drainage was maintained for 3-105 days (mean 31 days±26 [SD]). After three procedures (3/28; 11%) patients reported discomfort. No major complications were reported. CONCLUSION: This study suggests that posterior transperineal drainage is an effective, safe and well-tolerated procedure for the treatment of presacral abscess.


Asunto(s)
Absceso/diagnóstico por imagen , Absceso/cirugía , Drenaje/métodos , Adulto , Anciano , Anciano de 80 o más Años , Drenaje/efectos adversos , Femenino , Fluoroscopía , Humanos , Región Lumbosacra , Masculino , Persona de Mediana Edad , Perineo , Radiografía Intervencional , Estudios Retrospectivos , Cirugía Asistida por Computador , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
6.
Breast Cancer Res Treat ; 169(3): 549-559, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29460031

RESUMEN

BACKGROUND AND PURPOSE: We investigated the acute toxicity of accelerated partial breast irradiation using external beam (EB-APBI) or intraoperative radiotherapy (IORT) techniques in elderly breast cancer patients. MATERIALS AND METHODS: Women ≥ 60 years with unifocal breast tumors of ≤ 30 mm were eligible for this prospective multi-center cohort study. IORT was applied with electrons following lumpectomy (23.3 Gy). EB-APBI was delivered using 3D-CRT or IMRT in 10 daily fractions of 3.85 Gy within 6 weeks after surgery. Acute toxicity was scored using the CTCAE v3.0 at 3 months after treatment. Patient-reported symptoms were analyzed using visual analogue scales (VAS) for pain and fatigue (scale 0-10), and single items from the EORTC QLQ-C30 and Breast Cancer questionnaires. RESULTS: In total, 267 (IORT) and 206 (EB-APBI) patients were available for toxicity analysis. More patients experienced ≥ grade 2 CTCAE acute toxicity in the IORT group (10.4% IORT and 4.9% EB-APBI; p = 0.03); grade 3 toxicity was low (3.3% IORT and 1.5% EB-APBI; ns); and no grade 4 toxicity occurred. EB-APBI patients experienced less fatigue direct postoperatively (EORTC p < 0.00, VAS p < 0.00). After 3 months only pain, according to the VAS scale, was significantly worse in the EB-APBI group (p < 0.00). CONCLUSION: Acute toxicity after IORT and EB-APBI treatment is acceptable.


Asunto(s)
Braquiterapia/métodos , Neoplasias de la Mama/radioterapia , Cuidados Intraoperatorios , Factores de Edad , Anciano , Anciano de 80 o más Años , Braquiterapia/efectos adversos , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Femenino , Estudios de Seguimiento , Humanos , Cuidados Intraoperatorios/métodos , Mastectomía Segmentaria , Persona de Mediana Edad , Estadificación de Neoplasias , Medición de Resultados Informados por el Paciente , Radioterapia Adyuvante , Resultado del Tratamiento
7.
Occup Med (Lond) ; 67(9): 684-686, 2017 12 30.
Artículo en Inglés | MEDLINE | ID: mdl-29281066

RESUMEN

Background: The serum level of dehydroepiandrosterone sulphate (DHEA-S) has been suggested as a biological marker of stress. Aims: To assess the association between serum DHEA-S, psychosocial factors and musculoskeletal (MS) pain in university workers. Methods: The study population included voluntary workers at the scientific departments of the University of Trieste (Italy) who underwent periodical health surveillance from January 2011 to June 2012. DHEA-S level was analysed in serum. The assessment tools included the General Health Questionnaire (GHQ) and a modified Nordic musculoskeletal symptoms questionnaire. The relation between DHEA-S, individual characteristics, pain perception and psychological factors was assessed by means of multivariable linear regression analysis. Results: There were 189 study participants. The study population was characterized by high reward and low effort. Pain perception in the neck, shoulder, upper limbs, upper back and lower back was reported by 42, 32, 19, 29 and 43% of people, respectively. In multivariable regression analysis, gender, age and pain perception in the shoulder and upper limbs were significantly related to serum DHEA-S. Effort and overcommitment were related to shoulder and neck pain but not to DHEA-S. The GHQ score was associated with pain perception in different body sites and inversely to DHEA-S but significance was lost in multivariable regression analysis. Conclusions: DHEA-S was associated with age, gender and perception of MS pain, while effort-reward imbalance dimensions and GHQ score failed to reach the statistical significance in multivariable regression analysis.


Asunto(s)
Sulfato de Deshidroepiandrosterona/análisis , Dolor Musculoesquelético/diagnóstico , Adulto , Biomarcadores/análisis , Biomarcadores/sangre , Estudios Transversales , Sulfato de Deshidroepiandrosterona/sangre , Femenino , Humanos , Italia , Masculino , Persona de Mediana Edad , Dolor Musculoesquelético/fisiopatología , Psicología , Encuestas y Cuestionarios , Universidades/organización & administración
8.
Musculoskelet Surg ; 101(Suppl 2): 187-196, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28994021

RESUMEN

Radial head prostheses (RHP) have been developed to decrease the complications rate following a radial head resection surgery. The aim of the RHP is to replicate the physiological radiocapitellar tracking, reproducing the mechanical function of the native radial head: to stabilize the elbow and to shear the forces passing through the elbow along with the other stabilizers. The currently used RHP models try to achieve this target with three different prosthesis' strategies: (a) loose fit stem, (b) bipolar radial head or (c) anatomical radial head. Even if the radial head fixation is the preferred technique in every possible case and the resection can be still considered a possible option, in the last years there has been a growing worldwide consensus in using the radial head replacement in patients with unfixable radial head fractures, especially if associated with complex elbow instability. However, complications after a RHP are not uncommon, and their rate is raising as long as the implants number are increasing. The main difficulties are due to the implantation technique that needs to be performed with the same attention and precision used for the replacement of all the other joints, and to the concurrent treatment of the associated lesions. A personalized postoperative rehabilitation program is essential for obtaining good results and decreasing the complications rate. Concern exists for the young age of the patients that often require a RHP: personal experience and literature analysis suggest that if the clinical and radiographic results are positive after a 6-12-month follow-up, good outcomes can be also expected at a medium- or long-term follow-up.


Asunto(s)
Articulación del Codo/cirugía , Prótesis de Codo , Implantación de Prótesis/métodos , Radio (Anatomía)/cirugía , Artroplastia/métodos , Artroplastia/rehabilitación , Fenómenos Biomecánicos , Contraindicaciones de los Procedimientos , Fijación Interna de Fracturas/métodos , Fijación Interna de Fracturas/rehabilitación , Humanos , Inestabilidad de la Articulación/etiología , Inestabilidad de la Articulación/prevención & control , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/prevención & control , Diseño de Prótesis , Implantación de Prótesis/rehabilitación , Fracturas del Radio/cirugía , Resultado del Tratamiento
9.
Phys Rev Lett ; 119(15): 154801, 2017 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-29077438

RESUMEN

A simple method for generating single-spike hard x-ray pulses in free-electron lasers (FELs) has been developed at the Linac Coherent Light Source (LCLS). This is realized by nonlinear bunch compression using 20-pC bunch charge, demonstrated in the hard x-ray regime at 5.6 and 9 keV, respectively. Measurements show about half of the FEL shots containing a single-spike spectrum. At 5.6-keV photon energy, the single-spike shots have a mean pulse energy of about 10 µJ with 70% intensity fluctuation and the pulse full width at half maximum is evaluated to be at 200-as level.

10.
Phys Rev Lett ; 119(3): 031101, 2017 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-28777601

RESUMEN

We present a novel interpretation of the γ-ray diffuse emission measured by Fermi-LAT and H.E.S.S. in the Galactic center (GC) region and the Galactic ridge (GR). In the first part we perform a data-driven analysis based on PASS8 Fermi-LAT data: We extend down to a few GeV the spectra measured by H.E.S.S. and infer the primary cosmic-ray (CR) radial distribution between 0.1 and 3 TeV. In the second part we adopt a CR transport model based on a position-dependent diffusion coefficient. Such behavior reproduces the radial dependence of the CR spectral index recently inferred from the Fermi-LAT observations. We find that the bulk of the GR emission can be naturally explained by the interaction of the diffuse steady-state Galactic CR sea with the gas present in the central molecular zone. Although we confirm the presence of a residual radial-dependent emission associated with a central source, the relevance of the large-scale diffuse component prevents to claim a solid evidence of GC pevatrons.

11.
Nat Commun ; 8: 15461, 2017 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-28580940

RESUMEN

Free-electron lasers providing ultra-short high-brightness pulses of X-ray radiation have great potential for a wide impact on science, and are a critical element for unravelling the structural dynamics of matter. To fully harness this potential, we must accurately know the X-ray properties: intensity, spectrum and temporal profile. Owing to the inherent fluctuations in free-electron lasers, this mandates a full characterization of the properties for each and every pulse. While diagnostics of these properties exist, they are often invasive and many cannot operate at a high-repetition rate. Here, we present a technique for circumventing this limitation. Employing a machine learning strategy, we can accurately predict X-ray properties for every shot using only parameters that are easily recorded at high-repetition rate, by training a model on a small set of fully diagnosed pulses. This opens the door to fully realizing the promise of next-generation high-repetition rate X-ray lasers.

12.
Nutr Metab Cardiovasc Dis ; 27(5): 462-469, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28428026

RESUMEN

BACKGROUND AND AIMS: Anthracyclines are effective anticancer drugs that have improved prognosis of hundred thousand cancer patients worldwide and are currently the most common chemotherapeutic agents used for the treatment of blood, breast, ovarian and lung cancers. However, their use is limited because of a cumulative dose-dependent and irreversible cardiotoxicity that can cause progressive cardiomyopathy and congestive heart failure. Aim of the present study was to determine the cardioprotective activity of a dietary source of cyanidin 3-glucoside (C3G), such as purple corn, against doxorubicin (DOX)-induced cardiotoxicity in mice. METHODS AND RESULTS: In vitro studies on murine HL-1 cardiomyocytes showed that pretreatment with both pure C3G and purple corn extract improved survival upon DOX treatment. However, C3G and purple corn extract did not affect the cytotoxic effect of DOX on human cancer cell lines. We then validated in vivo the protective role of a C3G-enriched diet against DOX-induced cardiotoxicity by comparing the effect of dietary consumption of corn isogenic lines with high levels of anthocyanins (purple corn - Red diet - RD) or without anthocyanins (yellow corn - Yellow diet - YD) incorporated in standard rodent diets. Results showed that mice fed RD survived longer than mice fed YD upon injection of a toxic amount of DOX. In addition, ultrastructural analysis of hearts from mice fed RD showed reduced histopathological alterations. CONCLUSION: Dietary intake of C3G from purple corn protects mice against DOX-induced cardiotoxicity.


Asunto(s)
Alimentación Animal , Antocianinas/farmacología , Doxorrubicina , Glucósidos/farmacología , Cardiopatías/prevención & control , Miocitos Cardíacos/efectos de los fármacos , Extractos Vegetales/farmacología , Sustancias Protectoras/farmacología , Zea mays/química , Animales , Antocianinas/aislamiento & purificación , Cardiotoxicidad , Supervivencia Celular/efectos de los fármacos , Citoprotección , Dieta , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Femenino , Regulación de la Expresión Génica , Glucósidos/aislamiento & purificación , Células HeLa , Cardiopatías/inducido químicamente , Cardiopatías/metabolismo , Cardiopatías/patología , Humanos , Células MCF-7 , Ratones Endogámicos C57BL , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Fitoterapia , Extractos Vegetales/aislamiento & purificación , Plantas Medicinales , Sustancias Protectoras/aislamiento & purificación , Factores de Tiempo
13.
Musculoskelet Surg ; 100(Suppl 1): 61-71, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27900701

RESUMEN

BACKGROUND: In the recent years, considerable improvements have come in biomechanical knowledge about the role of elbow stabilizers. In particular, the complex interactions among the different stabilizers when injured at the same time have been better understood. Anyway, uncertainties about both nomenclature and classification still exist in the definition of the different patterns of instability. MATERIAL AND METHODS: The authors examine the literature of the last 130 years about elbow instability classification, analyzing the intuitions and the value of each of them. However, because of the lack of a satisfactory classification, in 2015 a working group has been created inside SICSeG (Italian Society of Shoulder and Elbow Surgery) with the aim of defining an exhaustive classification as simple, complete and reproducible as possible. RESULTS: A new all-inclusive elbow instability classification is proposed. This classification considers two main parameters: timing (acute and chronic forms) and involved stabilizers (simple and complex forms), and four secondary parameters: etiology (traumatic, rheumatic, congenital…), the involved joint (radius and ulna as a single unit articulating with the humerus or the proximal radio-ulnar joint), the degree of displacement (dislocation or subluxation) and the mechanism of instability or dislocation (PLRI, PMRI, direct axial loading, pure varus or valgus stress). CONCLUSIONS: This classification is at the same time complete enough to include all the instability patterns and practical enough to be effectively used in the clinical practice. This classification can help in defining a shared language, can improve our understanding of the disorder, reduce misunderstanding of diagnosis and improve comparison among different case series.


Asunto(s)
Lesiones de Codo , Articulación del Codo , Inestabilidad de la Articulación/clasificación , Articulación del Codo/diagnóstico por imagen , Humanos , Italia , Inestabilidad de la Articulación/diagnóstico , Inestabilidad de la Articulación/cirugía , Rango del Movimiento Articular , Sociedades Médicas , Resultado del Tratamiento
14.
Rev Sci Instrum ; 87(8): 083113, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27587106

RESUMEN

A non-destructive diagnostic method for the characterization of circularly polarized, ultraintense, short wavelength free-electron laser (FEL) light is presented. The recently installed Delta undulator at the LCLS (Linac Coherent Light Source) at SLAC National Accelerator Laboratory (USA) was used as showcase for this diagnostic scheme. By applying a combined two-color, multi-photon experiment with polarization control, the degree of circular polarization of the Delta undulator has been determined. Towards this goal, an oriented electronic state in the continuum was created by non-resonant ionization of the O2 1s core shell with circularly polarized FEL pulses at hν ≃ 700 eV. An also circularly polarized, highly intense UV laser pulse with hν ≃ 3.1 eV was temporally and spatially overlapped, causing the photoelectrons to redistribute into so-called sidebands that are energetically separated by the photon energy of the UV laser. By determining the circular dichroism of these redistributed electrons using angle resolving electron spectroscopy and modeling the results with the strong-field approximation, this scheme allows to unambiguously determine the absolute degree of circular polarization of any pulsed, ultraintense XUV or X-ray laser source.

15.
Phys Rev Lett ; 116(25): 254801, 2016 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-27391728

RESUMEN

In this Letter we report the experimental demonstration of a new temporal shaping technique for x-ray free-electron lasers (FELs). This technique is based on the use of a spectrally shaped infrared (IR) laser and allows optical control of the x-ray generation process. By accurately manipulating the spectral amplitude and phase of the IR laser, we can selectively modify the electron bunch longitudinal emittance thus controlling the duration of the resulting x-ray pulse down to the femtosecond time scale. Unlike other methods currently in use, optical shaping is directly applicable to the next generation of high-average power x-ray FELs such as the Linac Coherent Light Source-II or the European X-FEL, and it enables pulse shaping of FELs at the highest repetition rates. Furthermore, this laser-shaping technique paves the way for flexible tailoring of complex multicolor FEL pulse patterns required for nonlinear multidimensional x-ray spectroscopy as well as novel multicolor diffraction imaging schemes.

16.
Nat Commun ; 7: 11652, 2016 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-27212390

RESUMEN

New capabilities at X-ray free-electron laser facilities allow the generation of two-colour femtosecond X-ray pulses, opening the possibility of performing ultrafast studies of X-ray-induced phenomena. Particularly, the experimental realization of hetero-site-specific X-ray-pump/X-ray-probe spectroscopy is of special interest, in which an X-ray pump pulse is absorbed at one site within a molecule and an X-ray probe pulse follows the X-ray-induced dynamics at another site within the same molecule. Here we show experimental evidence of a hetero-site pump-probe signal. By using two-colour 10-fs X-ray pulses, we are able to observe the femtosecond time dependence for the formation of F ions during the fragmentation of XeF2 molecules following X-ray absorption at the Xe site.

17.
Ann Surg Oncol ; 23(9): 2858-65, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27075325

RESUMEN

BACKGROUND: The purpose of this study was to identify the ten most frequent complications after surgery for stage I-III colon cancer and to assess the association between these complications and overall survival, conditional overall survival, and recurrences. METHODS: All patients who underwent surgery for stage I-III colon cancer in five hospitals in the Western region of the Netherlands were identified. Crude and adjusted Cox proportional hazards models were used to study the association between complications and 1-year overall survival, 5-year overall survival, 5-year conditional overall survival, and 5-year disease-free period. RESULTS: Data from 761 patients were used for the analyses. Complications were associated with decreased 1-year overall survival (hazard ratio (HR) 2.87, 95 % confidence interval (CI) 1.82-4.51; p < 0.001), 5-year overall survival (HR 1.59, 95 % CI 1.25-2.04; p < 0.001), and 5-year conditional overall survival (HR 1.34, 95 % CI 1.06-1.69; p = 0.016), whereas an increasing number of complications had no additional impact. Anastomotic leakage, excessive blood loss, and (abdominal) sepsis were associated with reduced 1-year overall survival, anastomotic leakage, delirium, abscess, and (abdominal) sepsis with reduced 5-year overall survival, and anastomotic leakage, delirium, and abscess with reduced 5-year conditional overall survival. Anastomotic leakage, electrolyte disorders, and abscess were risk factors for recurrence within five years. CONCLUSIONS: Our results demonstrate the serious impact of the most frequent complications after surgery for colon cancer on short-term and long-term outcomes. This study confirms the prolonged impact of surgery and demonstrates that complications result not only in reduced 1-year survival, but also in reduced long-term outcomes.


Asunto(s)
Neoplasias del Colon/cirugía , Hemorragia Gastrointestinal/etiología , Complicaciones Posoperatorias/etiología , Absceso/etiología , Anciano , Fuga Anastomótica/etiología , Arritmias Cardíacas/etiología , Neoplasias del Colon/patología , Delirio/etiología , Supervivencia sin Enfermedad , Femenino , Humanos , Ileus/etiología , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neumonía/etiología , Modelos de Riesgos Proporcionales , Sepsis/etiología , Tasa de Supervivencia , Factores de Tiempo , Infecciones Urinarias/etiología , Desequilibrio Hidroelectrolítico/etiología
18.
Eur J Surg Oncol ; 41(9): 1188-96, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26184850

RESUMEN

AIM: The value of frequent Carcino-Embryonic Antigen (CEA) measurements and CEA-triggered imaging for detecting recurrent disease in colorectal cancer (CRC) patients was investigated in search for an evidence-based follow-up protocol. METHODS: This is a randomized-controlled multicenter prospective study using a stepped-wedge cluster design. From October 2010 to October 2012, surgically treated non-metastasized CRC patients in follow-up were followed in eleven hospitals. Clusters of hospitals sequentially changed their usual follow-up care into an intensified follow-up schedule consisting of CEA measurements every two months, with imaging in case of two CEA rises. The primary outcome measures were the proportion of recurrences that could be treated with curative intent, recurrences with definitive curative treatment outcome, and the time to detection of recurrent disease. RESULTS: 3223 patients were included; 243 recurrences were detected (7.5%). A higher proportion of recurrences was detected in the intervention protocol compared to the control protocol (OR = 1.80; 95%-CI: 1.33-2.50; p = 0.0004). The proportion of recurrences that could be treated with curative intent was higher in the intervention protocol (OR = 2.84; 95%-CI: 1.38-5.86; p = 0.0048) and the proportion of recurrences with definitive curative treatment outcome was also higher (OR = 3.12, 95%-CI: 1.25-6.02, p-value: 0.0145). The time to detection of recurrent disease was significantly shorter in the intensified follow-up protocol (HR = 1.45; 95%-CI: 1.08-1.95; p = 0.013). CONCLUSION: The CEAwatch protocol detects recurrent disease after colorectal cancer earlier, in a phase that a significantly higher proportion of recurrences can be treated with curative intent.


Asunto(s)
Biomarcadores de Tumor/sangre , Antígeno Carcinoembrionario/sangre , Carcinoma/cirugía , Colectomía , Neoplasias Colorrectales/cirugía , Recurrencia Local de Neoplasia/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma/sangre , Neoplasias Colorrectales/sangre , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/sangre , Recurrencia Local de Neoplasia/cirugía
19.
Nat Commun ; 6: 6369, 2015 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-25744344

RESUMEN

The X-ray free-electron laser has opened a new era for photon science, improving the X-ray brightness by ten orders of magnitude over previously available sources. Similar to an optical laser, the spectral and temporal structure of the radiation pulses can be tailored to the specific needs of many experiments by accurately manipulating the lasing medium, that is, the electron beam. Here we report the generation of mJ-level two-colour hard X-ray pulses of few femtoseconds duration with an XFEL driven by twin electron bunches at the Linac Coherent Light Source. This performance represents an improvement of over an order of magnitude in peak power over state-of-the-art two-colour XFELs. The unprecedented intensity and temporal coherence of this new two-colour X-ray free-electron laser enable an entirely new set of scientific applications, ranging from X-ray pump/X-ray probe experiments to the imaging of complex biological samples with multiple wavelength anomalous dispersion.

20.
Phys Rev Lett ; 114(5): 054801, 2015 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-25699448

RESUMEN

The Linac Coherent Light Source has added a self-seeding capability to the soft x-ray range using a grating monochromator system. We report the demonstration of soft x-ray self-seeding with a measured resolving power of 2000-5000, wavelength stability of 10(-4), and an increase in peak brightness by a factor of 2-5 across the photon energy range of 500-1000 eV. By avoiding the need for a monochromator at the experimental station, the self-seeded beam can deliver as much as 50-fold higher brightness to users.

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