46 research outputs found

    Extended calibration range for prompt photon emission in ion beam irradiation

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    Monitoring the dose delivered during proton and carbon ion therapy is still a matter of research. Among the possible solutions, several exploit the measurement of the single photon emission from nuclear decays induced by the irradiation. To fully characterize such emission the detectors need development, since the energy spectrum spans the range above the MeV that is not traditionally used in medical applications. On the other hand, a deeper understanding of the reactions involving gamma production is needed in order to improve the physic models of Monte Carlo codes, relevant for an accurate prediction of the prompt-gamma energy spectrum.This paper describes a calibration technique tailored for the range of energy of interest and reanalyzes the data of the interaction of a 80MeV/u fully stripped carbon ion beam with a Poly-methyl methacrylate target. By adopting the FLUKA simulation with the appropriate calibration and resolution a significant improvement in the agreement between data and simulation is reported.Comment: 4 pages, 7 figures, Submitted to JINS

    Multicenter phase II trial of preoperative induction chemotherapy followed by chemoradiation with docetaxel and cisplatin for locally advanced esophageal carcinoma (SAKK 75/02)

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    Background: This multicenter phase II study investigated the efficacy and feasibility of preoperative induction chemotherapy followed by chemoradiation and surgery in patients with esophageal carcinoma. Patients and methods: Patients with locally advanced resectable squamous cell carcinoma or adenocarcinoma of the esophagus received induction chemotherapy with cisplatin 75 mg/m2 and docetaxel (Taxotere) 75 mg/m2 on days 1 and 22, followed by radiotherapy of 45 Gy (25 × 1.8 Gy) and concurrent chemotherapy comprising cisplatin 25 mg/m2 and docetaxel 20 mg/m2 weekly for 5 weeks, followed by surgery. Results: Sixty-six patients were enrolled at eleven centers and 57 underwent surgery. R0 resection was achieved in 52 patients. Fifteen patients showed complete, 16 patients nearly complete and 26 patients poor pathological remission. Median overall survival was 36.5 months and median event-free survival was 22.8 months. Squamous cell carcinoma and good pathologically documented response were associated with longer survival. Eighty-two percent of all included patients completed neoadjuvant therapy and survived for 30 days after surgery. Dysphagia and mucositis grade 3/4 were infrequent (<9%) during chemoradiation. Five patients (9%) died due to surgical complications. Conclusions: This neoadjuvant, taxane-containing regimen was efficacious and feasible in patients with locally advanced esophageal cancer in a multicenter, community-based setting and represents a suitable backbone for further investigatio

    From the bench to practice - Field integration of community-based services for older citizens with different levels of functional limitation across European Regions

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    The meeting of the European Innovation Partnership on Active and Healthy Ageing (EIPonAHA) action group A3 together with members of the Reference site collaborative network (RSCN) in December 2019 in Rome focused on integration of evidence-based approaches on health and care delivery for older citizens at different levels of needs with expertise coming from stakeholder across Europe. It was the final aim of the group to co-create culturally sensitive pathways and facilitate co-ownership for further implementation of the pathways in different care systems across Europe. The study design is a mixed method approach. Based on data analysis from a cohort of community-dwelling over-65 citizens in the framework of a longitudinal observational study in Rome, which included health, social and functional capacity data, three personas profiles were developed: the pre-frail, the frail and the very frail personas. Based on these data, experts were asked to co-create care pathways due to evidence and eminence during a workshop and included into a final report. All working groups agreed on a common understanding that integration of care means person-centered integration of health and social care, longitudinally provided across primary and secondary health care including citizens' individual social, economic and human resources. Elements for consideration during care for pre-frail people are loneliness and social isolation, which, lead to limitation of physical autonomy in the light of reduced access to social support. Frail people need adaption of environmental structures and, again, social resource allocation to maintain at home. Very frail are generally vulnerable patients with complex needs. Most of them remain at home because of a strong individual social support and integrated health care delivery. The approach described in this publication may represent a first approach to scaling-up care delivery in a person-centered approach

    90Y-DOTA-nimotuzumab: synthesis of a promising β⁻ radiopharmaceutical

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    BACKGROUND: Nimotuzumab is a humanized anti-epidermal growth factor receptor (EGFR) monoclonal antibody, nowadays used for tumour immunochemotherapy. This study aimed to label the conjugate DOTA-nimotuzumab with yttrium-90, in order to provide a beta- emitting radioimmunoconjugate (90Y-DOTA-nimotuzumab) potentially useful to assess the feasibility of a new radio-guided surgery approach.METHODS: The synthesis of 90Y-DOTA-nimotuzumab was performed in two days. Nimotuzumab was conjugated with a 50 fold excess of DOTA and then labelled with 90Y3+. The 90Y-DOTA-nimotuzumab preparation was optimized considering several parameters such as pH, temperature and reaction volume. Moreover, the 90Y-DOTA-nimotuzumab stability was evaluated in human plasma.RESULTS: The radioimmunoconjugate 90Y-DOTA-nimotuzumab was obtained with a radiochemical purity greater than 96%, and showed a good stability at 20°C as well as at 37°C in human plasma.CONCLUSIONS: The optimized conditions for a mild and easy preparation of 90Y-DOTA-nimotuzumab joined to a promising stability under physiological conditions suggest to propose this radioimmunoconjugate as a potential diagnostic radiopharmaceutical for beta- radio-guided surgery

    Phase II study of capecitabine and oxaliplatin given prior to and concurrently with preoperative pelvic radiotherapy in patients with locally advanced rectal cancer

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    This multicentre phase II study evaluated the efficacy and safety of preoperative capecitabine plus oxaliplatin and radiotherapy (RT) in patients with locally advanced rectal cancer (T3/T4 rectal adenocarcinoma with or without nodal involvement). Treatment consisted of one cycle of XELOX (capecitabine 1000 mg m−2 bid on days 1–14 and oxaliplatin 130 mg m−2 on day 1), followed by RT (1.8 Gy fractions 5 days per week for 5 weeks) plus CAPOX (capecitabine 825 mg m−2 bid on days 22–35 and 43–56, and oxaliplatin 50 mg m−2 on days 22, 29, 43 and 50). Surgery was recommended 5 weeks after completion of chemoradiotherapy. The primary end point was pathological complete tumour response (pCR). Sixty patients were enrolled. In the intent-to-treat population, the pCR rate was 23% (95% CI: 13–36%). 58 patients underwent surgery; R0 resection was achieved in 57 (98%) patients, including all 5 patients with T4 tumours. Sphincter preservation was achieved in 49 (84%) patients. Tumour and/or nodal downstaging was observed in 39 (65%) patients. The most common grade 3/4 adverse events were diarrhoea (20%) and lymphocytopaenia (43%). Preoperative capecitabine, oxaliplatin and RT achieved encouraging rates of pCR, R0 resection, sphincter preservation and tumour downstaging in patients with locally advanced rectal cancer

    The effect of mechanical loading on osteogenesis of human dental pulp stromal cells in a novel in vitro model

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    Tooth loss often results in alveolar bone resorption because of lack of mechanical stimulation. Thus, the mechanism of mechanical loading on stem cell osteogenesis is crucial for alveolar bone regeneration. We have investigated the effect of mechanical loading on osteogenesis in human dental pulp stromal cells (hDPSCs) in a novel in vitro model. Briefly, 1 × 107 hDPSCs were seeded into 1 ml 3 % agarose gel in a 48-well-plate. A loading tube was then placed in the middle of the gel to mimic tooth-chewing movement (1 Hz, 3 × 30 min per day, n = 3). A non-loading group was used as a control. At various time points, the distribution of live/dead cells within the gel was confirmed by fluorescence markers and confocal microscopy. The correlation and interaction between the factors (e.g. force, time, depth and distance) were statistically analysed. The samples were processed for histology and immunohistochemistry. After 1-3 weeks of culture in the in-house-designed in vitro bioreactor, fluorescence imaging confirmed that additional mechanical loading increased the viable cell numbers over time as compared with the control. Cells of various phenotypes formed different patterns away from the reaction tube. The cells in the middle part of the gel showed enhanced alkaline phosphatase staining at week 1 but reduced staining at weeks 2 and 3. Additional loading enhanced Sirius Red and type I collagen staining compared with the control. We have thus successfully developed a novel in-house-designed in vitro bioreactor mimicking the biting force to enhance hDPSC osteogenesis in an agarose scaffold and to promote bone formation and/or prevent bone resorption

    Tension-Compression Loading with Chemical Stimulation Results in Additive Increases to Functional Properties of Anatomic Meniscal Constructs

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    Objective: This study aimed to improve the functional properties of anatomically-shaped meniscus constructs through simultaneous tension and compression mechanical stimulation in conjunction with chemical stimulation. Methods: Scaffoldless meniscal constructs were subjected to simultaneous tension and compressive stimulation and chemical stimulation. The temporal aspect of mechanical loadingwas studied by employing two separate five day stimulation periods. Chemical stimulation consisted of the application of a catabolic GAG-depleting enzyme, chondroitinase ABC (C-ABC), and an anabolic growth factor, TGF-b1. Mechanical and chemical stimulation combinations were studied through a full-factorial experimental design and assessed for histological, biochemical, and biomechanical properties following 4 wks of culture. Results: Mechanical loading applied from days 10–14 resulted in significant increases in compressive, tensile, and biochemical properties of meniscal constructs. When mechanical and chemical stimuliwere combined significant additive increases in collagen per wet weight (4-fold), compressive instantaneous (3-fold) and relaxation (2-fold) moduli, and tensile moduli in the circumferential (4-fold) and radial (6-fold) directions were obtained. Conclusions: This study demonstrates that a stimulation regimen of simultaneous tension and compression mechanical stimulation, C-ABC, and TGF-b1 is able to create anatomic meniscus constructs replicating the compressive mechanica

    Influenza Virus Respiratory Infection and Transmission Following Ocular Inoculation in Ferrets

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    While influenza viruses are a common respiratory pathogen, sporadic reports of conjunctivitis following human infection demonstrates the ability of this virus to cause disease outside of the respiratory tract. The ocular surface represents both a potential site of virus replication and a portal of entry for establishment of a respiratory infection. However, the properties which govern ocular tropism of influenza viruses, the mechanisms of virus spread from ocular to respiratory tissue, and the potential differences in respiratory disease initiated from different exposure routes are poorly understood. Here, we established a ferret model of ocular inoculation to explore the development of virus pathogenicity and transmissibility following influenza virus exposure by the ocular route. We found that multiple subtypes of human and avian influenza viruses mounted a productive virus infection in the upper respiratory tract of ferrets following ocular inoculation, and were additionally detected in ocular tissue during the acute phase of infection. H5N1 viruses maintained their ability for systemic spread and lethal infection following inoculation by the ocular route. Replication-independent deposition of virus inoculum from ocular to respiratory tissue was limited to the nares and upper trachea, unlike traditional intranasal inoculation which results in virus deposition in both upper and lower respiratory tract tissues. Despite high titers of replicating transmissible seasonal viruses in the upper respiratory tract of ferrets inoculated by the ocular route, virus transmissibility to naïve contacts by respiratory droplets was reduced following ocular inoculation. These data improve our understanding of the mechanisms of virus spread following ocular exposure and highlight differences in the establishment of respiratory disease and virus transmissibility following use of different inoculation volumes and routes

    A modern network approach to revisiting the positive and negative affective schedule (PANAS) construct validity

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    Introduction: The factor structure of the Positive and Negative Affective Schedule (PANAS) is still a topic of debate. There are several reasons why using Exploratory Graph Analysis (EGA) for scale validation is advantageous and can help understand and resolve conflicting results in the factor analytic literature. Objective: The main objective of the present study was to advance the knowledge regarding the factor structure underlying the PANAS scores by utilizing the different functionalities of the EGA method. EGA was used to (1) estimate the dimensionality of the PANAS scores, (2) establish the stability of the dimensionality estimate and of the item assignments into the dimensions, and (3) assess the impact of potential redundancies across item pairs on the dimensionality and structure of the PANAS scores. Method: This assessment was carried out across two studies that included two large samples of participants. Results and Conclusion: In sum, the results are consistent with a two-factor oblique structure.Fil: Flores Kanter, Pablo Ezequiel. Universidad Empresarial Siglo XXI; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Garrido, Luis Eduardo. Pontificia Universidad Católica Madre y Maestra; República DominicanaFil: Moretti, Luciana Sofía. Universidad Empresarial Siglo XXI; Argentina. Pontificia Universidad Católica Madre y Maestra; República Dominicana. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Medrano, Leonardo. Universidad Empresarial Siglo XXI; Argentina. Pontificia Universidad Católica Madre y Maestra; República Dominicana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
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