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Lymphatic endothelial cells (LECs) express MHC class II (MHC-II) upon IFN-γ stimulation, yet recent evidence suggests that LECs cannot activate naive or memory CD4+ T cells. In this article, we show that IFN-γ-activated human dermal LECs can robustly reactivate allogeneic human memory CD4+ T cells (hCD4+ TMs), but only when TGF-ß signaling is inhibited. We found that in addition to upregulating MHC-II, IFN-γ also induces LECs to upregulate glycoprotein A repetitions predominant, which anchors latent TGF-ß to the membrane and potentially inhibits T cell activation. Indeed, hCD4+ TM proliferation was substantially increased when LEC-CD4+ TM cultures were treated with a TGF-ß receptor type 1 inhibitor or when glycoprotein A repetitions predominant expression was silenced in LECs. Reactivated hCD4+ TMs were characterized by their proliferation, CD25 expression, and cytokine secretion. CD4+ TM reactivation was dependent on LEC expression of MHC-II, confirming direct TCR engagement. Although CD80 and CD86 were not detected on LECs, the costimulatory molecules OX40L and ICOSL were upregulated upon cytokine stimulation; however, blocking these did not affect CD4+ TM reactivation by LECs. Finally, we found that human dermal LECs also supported the maintenance of Foxp3-expressing hCD4+ TMs independently of IFN-γ-induced MHC-II. Together, these results demonstrate a role for LECs in directly modulating CD4+ TM reactivation under inflammatory conditions and point to LEC-expressed TGF-ß as a negative regulator of this activation.
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Linfócitos T CD4-Positivos , Antígenos de Histocompatibilidade Classe II , Humanos , Antígenos de Histocompatibilidade Classe II/metabolismo , Células Endoteliais , Antígenos CD4 , Citocinas , Moléculas de Adesão Celular , Interferon gama , Fator de Crescimento Transformador betaRESUMO
OBJECTIVE AND DESIGN: BacSp222 bacteriocin is a bactericidal and proinflammatory peptide stimulating immune cells to produce selected cytokines and NO in NF-ĸB dependent manner. This study aims to identify the receptor which mediates this activity. METHODS: We applied fluorescently labeled BacSp222 and a confocal microscopy imaging to analyze the direct interaction of the bacteriocin with the cells. Reporter HEK-Blue cells overexpressing human toll-like receptors (TLR2, TLR4, TLR5 or TLR2/TLR1 and TLR2/TLR6 heterodimers) were stimulated with BacSp222, and then the activity of NF-ĸB-dependent secreted embryonic alkaline phosphatase (SEAP) was measured. In turn, formylated peptide receptor (FPR) or TLR2 antagonists were used to verify bacteriocin-stimulated TNF production by murine monocyte-macrophage cell lines. RESULTS: BacSp222 undergoes internalization into cells without disturbing the cell membrane. FPR antagonists do not affect TNF produced by BacSp222-stimulated murine macrophage-like cells. In contrast, BacSp222 stimulates NF-ĸB activation in HEK-Blue overexpressing TLR2 or TLR2/TLR6 heterodimer, but not TLR2/TLR1, TLR4 or TLR5 receptors. Moreover, TLR2-specific antagonists inhibit NF-ĸB signaling in BacSp222-stimulated HEK-Blue TLR2/TLR6 cells and reduce TNF release by BacSp222-treated RAW 264.7 and P388.D1. CONCLUSIONS: BacSp222 is a novel ligand for TLR2/TLR6 heterodimer. By binding TLR complex the bacteriocin undergoes internalization, inducing proinflammatory signaling that employs MyD88 and NF-ĸB pathways.
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Bacteriocinas , Receptor 6 Toll-Like , Humanos , Animais , Camundongos , Ligantes , Receptor 6 Toll-Like/metabolismo , NF-kappa B/metabolismo , Receptor 1 Toll-Like , Receptor 2 Toll-Like/metabolismo , Receptor 5 Toll-Like , Receptor 4 Toll-Like , Bacteriocinas/farmacologiaRESUMO
Background and purpose: A collaborative network between proton therapy (PT) centres in Trento in Italy, Poland, Austria, Czech Republic and Sweden (IPACS) was founded to implement trials and harmonize PT. This is the first report of IPACS with the aim to show the level of harmonization that can be achieved for proton therapy planning of head and neck (sino-nasal) cancer.Methods: CT-data sets of five patients were included. During several face-to-face and online meetings, a common treatment planning protocol was developed. Each centre used its own treatment planning system (TPS) and planning approach with some restrictions specified in the treatment planning protocol. In addition, volumetric modulated arc therapy (VMAT) photon plans were created.Results: For CTV1, the average Dmedian was 59.3 ± 2.4 Gy(RBE) for protons and 58.8 ± 2.0 Gy(RBE) for VMAT (aim was 56 Gy(RBE)). For CTV2, the average Dmedian was 71.2 ± 1.0 Gy(RBE) for protons and 70.6 ± 0.4 Gy(RBE) for VMAT (aim was 70 Gy(RBE)). The average D2% for the spinal cord was 25.1 ± 8.5 Gy(RBE) for protons and 47.6 ± 1.4 Gy(RBE) for VMAT. The average D2% for chiasm was 46.5 ± 4.4 Gy(RBE) for protons and 50.8 ± 1.4 Gy(RBE) for VMAT, respectively. Robust evaluation was performed and showed the least robust plans for plans with a low number of beams.Discussion: In conclusion, several influences on harmonization were identified: adherence/interpretation to/of the protocol, available technology, experience in treatment planning and use of different beam arrangements. In future, all OARs that should be included in the optimization need to be specified in order to further harmonize treatment planning.
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Neoplasias de Cabeça e Pescoço/radioterapia , Cooperação Internacional , Órgãos em Risco , Terapia com Prótons/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Tronco Encefálico/efeitos da radiação , Cóclea/efeitos da radiação , Europa (Continente) , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Humanos , Laringe/efeitos da radiação , Neoplasias Nasais/diagnóstico por imagem , Neoplasias Nasais/radioterapia , Nervo Óptico/efeitos da radiação , Órgãos em Risco/efeitos da radiação , Neoplasias dos Seios Paranasais/diagnóstico por imagem , Neoplasias dos Seios Paranasais/radioterapia , Glândula Parótida/efeitos da radiação , Fótons/uso terapêutico , Radioterapia de Intensidade Modulada/métodos , Tomografia Computadorizada por Raios X , Carga TumoralRESUMO
BACKGROUND: One of the numerous sub-areas of interventional radiology is the use of X-rays in gastroenterology. X-ray fluoroscopy is applied in therapeutic procedures, including endoscopic retrograde cholangiopancreatography (ERCP) that is frequently performed. The ERCP procedure is aimed at imaging the pancreatic duct and biliary tracts. MATERIAL AND METHODS: In this paper radiation risk to the gastrenterologist performing ERCP procedures was investigated. The procedures were performed by a single gastroenterologist in the ERCP Laboratory, University Clinical Hospital Military Memorial Medical Academy - Central Veterans' Hospital in Lódz, Poland. The study comprised 2 series of measurements, one taken during the procedures with continuous fluoroscopy mode, the other during procedures with fluoroscopy in pulsed mode at a frequency of 3 pulses/s. Exposure parameters, anatomical data of patient and dose equivalents for the eyes, skin of the hand and the effective dose for whole body of the gastroenterologist were recorded during each procedure. RESULTS: The collected data cover 70 ERCP procedures - 40 procedures were controlled by continuous fluoroscopy and 30 by pulsed fluoroscopy. The results reveal that pulsed fluoroscopy makes it possible to reduce doses received by the gastroeneterologist from 45% to 60% compared to continuous fluoroscopy. CONCLUSIONS: Endoscopic retrograde cholangiopancreatography procedures can cause radiation risk to the gastroenterologist performing them. The use of continuous fluoroscopy can result in achieving an equivalent dose to eye lens nearly 20 mSv per year, i.e., the decreased annual limit recommended by the International Commission on Radiological Protection (ICRP). Med Pr 2017;68(6):735-741.
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Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Corpo Clínico Hospitalar , Exposição Ocupacional/efeitos adversos , Doses de Radiação , Proteção Radiológica/normas , Serviço Hospitalar de Radiologia/normas , Feminino , Gastroenterologistas/normas , Humanos , Masculino , Exposição Ocupacional/análise , Polônia , Monitoramento de Radiação/métodos , Radiologia Intervencionista/normas , Padrões de ReferênciaRESUMO
BACKGROUND: Extended control of staff exposure in interventional radiology has been legally required over the last few years. This is determined by a number of factors, including the type of procedure, technical conditions and methodology. In orthopedic procedures fluoroscopy is used to control surgical reconstructions. An influence of particular factors on the registered values of doses received by the members of medical team performing osteosynthesis for limb fractures is presented in this paper. MATERIAL AND METHODS: Doses received by individual interventional team members performing specific functions, operator, assisting physicians and scrub nurse, during a series of the procedures were measured. Each person was equipped with 4 dosimetric tools, containing thermoluminescent dosimeters, to measure the equivalent doses for the eyes, hand skin and the neck (outside the shield) and to evaluate effective doses. The investigations were performed in operational theatres of 3 hospitals in Lódz. RESULTS: The equivalent doses per one procedure for the eyes and hand skin of the operator were 0.029-0.073 mSv and 0.366-1.604 mSv, respectively. Significantly higher doses were noted during the procedures of intramedullary osteosynthesis, especially for the operator. An average age and body mass index (BMI) of patients treated in the monitored hospitals did not differ statistically. CONCLUSIONS: Based on the dosimetric measurements the following conclusions can be drawn: in orthopedic procedures of interventional radiology (IR) the exposure of the staff is mostly determined by the type of procedure and more precisely by its complexity and by the optimized use of X-ray unit, including pulsed fluoroscopy. It is also revealed that the operator is the most exposed person in the interventional team. Med Pr 2017;68(1):75-83.
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Corpo Clínico , Exposição Ocupacional/estatística & dados numéricos , Traumatismos Ocupacionais/epidemiologia , Exposição à Radiação/estatística & dados numéricos , Radiologia Intervencionista/estatística & dados numéricos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Lesões por Radiação/prevenção & controle , Monitoramento de Radiação/estatística & dados numéricos , Proteção Radiológica/estatística & dados numéricosRESUMO
BACKGROUND: In interventional radiology the highest radiation doses are usually recorded for both the medical staff and the patients. Interventional procedures with X-rays are implemented in a number of medical specializations. This paper concerns the exposure of interventional teams performing orthopedic procedures under X-rays control. MATERIAL AND METHODS: Doses for interventional teams were measured in the 3 Lódz hospitals. Thermoluminescent dosemeters were applied to measure the following dose equivalents: Hp(3) for eye lens, Hp(0.07) for palm skin, Hp(10) at the level of the neck without a protective shield (i.e., collar) and Hp(10) for the whole body on the front surface of the trunk (measured under the protective apron at the level of the chest). RESULTS: Doses for the operator who performs surgery, assisting physicians and scrub nurse were measured during 95 procedures. The highest doses were received by the operator the dose for eyes per 1 procedure did not exceed 0.1 mSv, the highest dose for hands was 1.6 mSv and the highest recorded effective dose was 0.02 mSv. CONCLUSIONS: On the basis of the results of measurements and their comparison with the values reported in the literature it may be concluded that the obtained results fall within the published reference range (for non-vascular procedures). This proves the compatibility of practice in the monitored Lódz hospitals with routine methodology applied in other interventional departments. The measurement results confirm that the usage of thermoluminescent dosimetry is fully adequate for the evaluation of exposure in interventional radiology and that the usage of at least 2 dosemeters for that staff is necessary. Med Pr 2017;68(2):221-227.
Assuntos
Fluoroscopia , Corpo Clínico , Exposição Ocupacional , Procedimentos Ortopédicos , Humanos , Dosimetria Termoluminescente , Raios XRESUMO
Research covered six variants: control, unfertilized carrots and carrots fertilized with: KIO3, Na2SeO4, Na2SeO3, KIO3 and simultaneously with Na2SeO4, and fertilized with KIO3 and simultaneously Na2SeO3. Carrots enriched with iodate or selenite, or both iodate and selenite, were characterized by higher amount of these minerals. Changes to the content of micro- and macroelements, during the cooking time of the carrots, both in peeled and unpeeled carrots, did not head in the same direction (increase, decrease and no change). However, cooking an unpeeled carrot generally resulted in the increased content of polyphenol and carotenoids. On the other hand, cooking peeled carrots led to a decrease in the content of polyphenol and a general lack of change in carotenoid content in relation to the unpeeled cooked carrot. During cooking, the antioxidant activity of the carrot being assessed changed together with the direction of changes in polyphenol content but not in line with the direction of changes in carotenoids.
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Daucus carota/química , Antioxidantes/análise , Carotenoides/análise , Culinária , Daucus carota/crescimento & desenvolvimento , Suplementos Nutricionais/análise , Fertilizantes , Análise de Alimentos , Manipulação de Alimentos , Humanos , Iodatos , Micronutrientes/análise , Minerais/análise , Necessidades Nutricionais , Valor Nutritivo , Polifenóis/análise , Compostos de Potássio , Ácido SeleniosoRESUMO
BACKGROUND: Numerous studies attest to the role that inappropriate food product groups in the human diet, including children and adolescents diet, leading to abnormal intakes of many important nutrients, such as minerals. OBJECTIVES: These studies were undertaken to assess the coverage of the recommended values for chosen minerals by 205 children and adolescents between the ages of 4 and 20 years, grown up in Krakow orphanages. MATERIALS AND METHODS: Sodium, magnesium, zinc, iron, copper, calcium and potassium concentrations in 112 diets of children and adolescents from 7 selected orphanages in Krakow in every season of the year were performed using AAS method. Results obtained were compared to recommended standards in Poland. RESULTS: Intakes of calcium and potassium were usually too low whilst adequate levels of dietary magnesium and calcium were seen only for the youngest children. Recommended dietary levels of zinc were met in all cases and mostly also for iron and copper. Sodium intakes were however excessive. CONCLUSIONS: The study demonstrates that regular a monitoring and adjusting of the diet is necessary for the assessed children and adolescents in order to correct dietary abnormalities.
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Análise de Alimentos , Preferências Alimentares , Micronutrientes/análise , Orfanatos/organização & administração , Oligoelementos/análise , Adolescente , Criança , Fenômenos Fisiológicos da Nutrição Infantil , Humanos , Avaliação Nutricional , Necessidades Nutricionais , Polônia/epidemiologia , Adulto JovemRESUMO
Lymphatic vessels transport fluid, antigens, and immune cells to the lymph nodes to orchestrate adaptive immunity and maintain peripheral tolerance. Lymphangiogenesis has been associated with inflammation, cancer metastasis, autoimmunity, tolerance and transplant rejection, and thus, targeted lymphatic ablation is a potential therapeutic strategy for treating or preventing such events. Here we define conditions that lead to specific and local closure of the lymphatic vasculature using photodynamic therapy (PDT). Lymphatic-specific PDT was performed by irradiation of the photosensitizer verteporfin that effectively accumulates within collecting lymphatic vessels after local intradermal injection. We found that anti-lymphatic PDT induced necrosis of endothelial cells and pericytes, which preceded the functional occlusion of lymphatic collectors. This was specific to lymphatic vessels at low verteporfin dose, while higher doses also affected local blood vessels. In contrast, light dose (fluence) did not affect blood vessel perfusion, but did affect regeneration time of occluded lymphatic vessels. Lymphatic vessels eventually regenerated by recanalization of blocked collectors, with a characteristic hyperplasia of peri-lymphatic smooth muscle cells. The restoration of lymphatic function occurred with minimal remodeling of non-lymphatic tissue. Thus, anti-lymphatic PDT allows control of lymphatic ablation and regeneration by alteration of light fluence and photosensitizer dose.
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Derme/fisiologia , Vasos Linfáticos/fisiologia , Fotoquimioterapia , Regeneração , Técnicas de Ablação , Animais , Morte Celular/efeitos dos fármacos , Derme/efeitos dos fármacos , Derme/efeitos da radiação , Relação Dose-Resposta a Droga , Orelha/patologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/patologia , Cinética , Luz , Vasos Linfáticos/efeitos dos fármacos , Camundongos , Fármacos Fotossensibilizantes/farmacologia , Regeneração/efeitos dos fármacos , Regeneração/efeitos da radiaçãoRESUMO
A questionnaire was developed by the members of WG12 of EURADOS in order to establish an overview of the current status of eye lens radiation dose monitoring in hospitals. The questionnaire was sent to medical physicists and radiation protection officers in hospitals across Europe. Specific topics were addressed in the questionnaire such as: knowledge of the proposed eye lens dose limit; monitoring and dosimetry issues; training and radiation protection measures. The results of the survey highlighted that the new eye lens dose limit can be exceeded in interventional radiology procedures and that eye lens protection is crucial. Personnel should be properly trained in how to use protective equipment in order to keep eye lens doses as low as reasonably achievable. Finally, the results also highlighted the need to improve the design of eye dosemeters in order to ensure satisfactory use by workers.
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Hospitais/estatística & dados numéricos , Cristalino/lesões , Exposição Ocupacional/prevenção & controle , Exposição Ocupacional/estatística & dados numéricos , Lesões por Radiação/prevenção & controle , Monitoramento de Radiação/estatística & dados numéricos , Proteção Radiológica/estatística & dados numéricos , Europa (Continente) , Traumatismos Oculares/prevenção & controle , Humanos , Cristalino/efeitos da radiação , Doses de Radiação , Inquéritos e QuestionáriosRESUMO
Applying a proton beam in radiotherapy enables precise irradiation of the tumor volume, but only for continuous assessment of changes in patient anatomy. Proton beam range uncertainties in the treatment process may originate not only from physical beam properties but also from patient-specific factors such as tumor shrinkage, edema formation and sinus filling, which are not incorporated in tumor volume safety margins. In this paper, we evaluated variations in dose distribution in proton therapy resulting from the differences observed in the control tomographic images and the dosimetric influence of applied adaptive treatment. The data from weekly computed tomography (CT) control scans of 21 patients, which serve as the basis for adaptive radiotherapy, were used for this study. Dosimetric analysis of adaptive proton therapy (APT) was performed on patients with head and neck (H&N) area tumors who were divided into two groups: patients with tumors in the sinus/nasal area and patients with tumors in the brain area. For this analysis, the reference treatment plans were forward-calculated using weekly control CT scans. A comparative evaluation of organ at risk (OAR) dose-volume histogram (DVH) parameters, as well as conformity and homogeneity indices, was conducted between the initial and recalculated dose distributions to assess the necessity of the adaptation process in terms of dosimetric parameters. Changes in PTV volume after replanning were observed in seventeen patient cases, showing a discrepancy of over 1 cm3 in ten cases. In these cases, tumor progression occurred in 30% of patients, while regression was observed in 70%. The statistical analysis indicates that the use of the adaptive planning procedure results in a statistically significant improvement in dose distribution, particularly in the PTV area. The findings led to the conclusion that the adaptive procedure provides significant advantages in terms of dose distribution within the treated volume. However, when considering the entire patient group, APT did not result in a statistically significant dose reduction in OARs (α = 0.05).
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The evidence for the value of particle therapy (PT) is still sparse. While randomized trials remain a cornerstone for robust comparisons with photon-based radiotherapy, data registries collecting real-world data can play a crucial role in building evidence for new developments. This Perspective describes how the European Particle Therapy Network (EPTN) is actively working on establishing a prospective data registry encompassing all patients undergoing PT in European centers. Several obstacles and hurdles are discussed, for instance harmonization of nomenclature and structure of technical and dosimetric data and data protection issues. A preferred approach is the adoption of a federated data registry model with transparent and agile governance to meet European requirements for data protection, transfer, and processing. Funding of the registry, especially for operation after the initial setup process, remains a major challenge.
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Sistema de Registros , Humanos , Europa (Continente) , Estudos Prospectivos , Neoplasias/radioterapia , Terapia com PrótonsRESUMO
PURPOSE: The aim of this work is to investigate the feasibility of the Jagiellonian Positron Emission Tomography (J-PET) scanner for intra-treatment proton beam range monitoring. METHODS: The Monte Carlo simulation studies with GATE and PET image reconstruction with CASToR were performed in order to compare six J-PET scanner geometries. We simulated proton irradiation of a PMMA phantom with a Single Pencil Beam (SPB) and Spread-Out Bragg Peak (SOBP) of various ranges. The sensitivity and precision of each scanner were calculated, and considering the setup's cost-effectiveness, we indicated potentially optimal geometries for the J-PET scanner prototype dedicated to the proton beam range assessment. RESULTS: The investigations indicate that the double-layer cylindrical and triple-layer double-head configurations are the most promising for clinical application. We found that the scanner sensitivity is of the order of 10-5 coincidences per primary proton, while the precision of the range assessment for both SPB and SOBP irradiation plans was found below 1 mm. Among the scanners with the same number of detector modules, the best results are found for the triple-layer dual-head geometry. The results indicate that the double-layer cylindrical and triple-layer double-head configurations are the most promising for the clinical application, CONCLUSIONS:: We performed simulation studies demonstrating that the feasibility of the J-PET detector for PET-based proton beam therapy range monitoring is possible with reasonable sensitivity and precision enabling its pre-clinical tests in the clinical proton therapy environment. Considering the sensitivity, precision and cost-effectiveness, the double-layer cylindrical and triple-layer dual-head J-PET geometry configurations seem promising for future clinical application.
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Terapia com Prótons , Prótons , Estudos de Viabilidade , Tomografia por Emissão de Pósitrons , Terapia com Prótons/métodos , Imagens de Fantasmas , Método de Monte CarloRESUMO
BACKGROUND AND PURPOSE: As no guidelines for pencil beam scanning (PBS) proton therapy (PT) of paediatric posterior fossa (PF) tumours exist to date, this study investigated planning techniques across European PT centres, with special considerations for brainstem and spinal cord sparing. MATERIALS AND METHODS: A survey and a treatment planning comparison were initiated across nineteen European PBS-PT centres treating paediatric patients. The survey assessed all aspects of the treatment chain, including but not limited to delineations, dose constraints and treatment planning. Each centre planned two PF tumour cases for focal irradiation, according to their own clinical practice but based on common delineations. The prescription dose was 54 Gy(RBE) for Case 1 and 59.4 Gy(RBE) for Case 2. For both cases, planning strategies and relevant dose metrics were compared. RESULTS: Seventeen (89 %) centres answered the survey, and sixteen (80 %) participated in the treatment planning comparison. In the survey, thirteen (68 %) centres reported using the European Particle Therapy Network definition for brainstem delineation. In the treatment planning study, while most centres used three beam directions, their configurations varied widely across centres. Large variations were also seen in brainstem doses, with a brainstem near maximum dose (D2%) ranging from 52.7 Gy(RBE) to 55.7 Gy(RBE) (Case 1), and from 56.8 Gy(RBE) to 60.9 Gy(RBE) (Case 2). CONCLUSION: This study assessed the European PBS-PT planning of paediatric PF tumours. Agreement was achieved in e.g. delineation-practice, while wider variations were observed in planning approach and consequently dose to organs at risk. Collaboration between centres is still ongoing, striving towards common guidelines.
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Neoplasias Infratentoriais , Terapia com Prótons , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Humanos , Terapia com Prótons/métodos , Neoplasias Infratentoriais/radioterapia , Europa (Continente) , Criança , Planejamento da Radioterapia Assistida por Computador/métodos , Pré-Escolar , Masculino , Feminino , Órgãos em Risco/efeitos da radiação , Tronco Encefálico/efeitos da radiaçãoRESUMO
Objective.Protons have advantageous dose distributions and are increasingly used in cancer therapy. At the depth of the Bragg peak range, protons produce a mixed radiation field consisting of low- and high-linear energy transfer (LET) components, the latter of which is characterized by an increased ionization density on the microscopic scale associated with increased biological effectiveness. Prediction of the yield and LET of primary and secondary charged particles at a certain depth in the patient is performed by Monte Carlo simulations but is difficult to verify experimentally.Approach.Here, the results of measurements performed with Timepix detector in the mixed radiation field produced by a therapeutic proton beam in water are presented and compared to Monte Carlo simulations. The unique capability of the detector to perform high-resolution single particle tracking and identification enhanced by artificial intelligence allowed to resolve the particle type and measure the deposited energy of each particle comprising the mixed radiation field. Based on the collected data, biologically important physics parameters, the LET of single protons and dose-averaged LET, were computed.Main results.An accuracy over 95% was achieved for proton recognition with a developed neural network model. For recognized protons, the measured LET spectra generally agree with the results of Monte Carlo simulations. The mean difference between dose-averaged LET values obtained from measurements and simulations is 17%. We observed a broad spectrum of LET values ranging from a fraction of keVµm-1to about 10 keVµm-1for most of the measurements performed in the mixed radiation fields.Significance.It has been demonstrated that the introduced measurement method provides experimental data for validation of LETDor LET spectra in any treatment planning system. The simplicity and accessibility of the presented methodology make it easy to be translated into a clinical routine in any proton therapy facility.
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Terapia com Prótons , Humanos , Terapia com Prótons/métodos , Prótons , Inteligência Artificial , Transferência Linear de Energia , Dosagem Radioterapêutica , Método de Monte Carlo , RadiometriaRESUMO
Quality control of therapeutic photon beams in the form of postal dose audits based on passive dosemeters is widely used in photon radiotherapy. On the other hand, no standardised dosimetry audit programme for proton centres has been established in Europe so far. We evaluated alanine/EPR dosimetry systems developed at the Istituto Superiore di Sanità (Italy), the Hasselt Universiteit (Belgium) and the Henryk Niewodniczanski Institute of Nuclear Physics Polish Academy of Sciences (Poland) for their applicability as a potential tool for routine mailed dose audits of passively scattered therapeutic proton beams. The evaluation was carried out in the form of an intercomparison. Dosemeters were irradiated in the 70 MeV proton beam at ocular proton therapy facility in the Cyclotron Centre Bronowice at the Henryk Niewodniczanski Institute of Nuclear Physics Polish Academy of Sciences in Krakow. A very good agreement was found between the dose measured by three laboratories and the delivered dose determined with an ionisation chamber. This, together with the inherent properties of alanine, such as non-destructive readout, tissue equivalence, weak energy dependence, dose rate independence and insignificant fading, makes alanine a good candidate for a dosemeter used in postal auditing in proton ocular radiotherapy.
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Terapia com Prótons , Prótons , Olho , Radiometria , AlaninaRESUMO
The bank vole is a common Cricetidae rodent that is a reservoir of several zoonotic pathogens and an emerging model in eco-immunology. Here, we add to a developing immunological toolkit for this species by testing the cross-reactivity of commercially available monoclonal antibodies (mAbs) to the bank vole lymphocyte differentiation molecules and a transcription factor. We show that a combination of mAbs against CD4, CD3, and Foxp3 allows flow cytometric distinction of the main subsets of T cells: putative helper CD4+, cytotoxic CD8+ (as CD3+CD4-) and regulatory CD4+Foxp3+. We also provide a comparative analysis of amino acid sequences of CD4, CD8αß, CD3εγδ and Foxp3 molecules for a number of commonly studied Cricetidae rodents and discuss mAb cross-reactivity patterns reported so far in this rodent family. We found that in case of mAbs targeting the extracellular portions of commonly used T cell markers, sequence similarity is a poor prognostic of cross-reactivity. Use of more conserved, intracellular molecules or molecule fragments is a more reliable approach in non-model species, but the necessity of cell fixation limit its application in, e.g. functional studies.
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Arvicolinae , Linfócitos T , Animais , Complexo CD3 , Citometria de Fluxo , Fatores de Transcrição ForkheadRESUMO
OBJECTIVE: The Jagiellonian PET (J-PET) technology, based on plastic scintillators, has been proposed as a cost effective tool for detecting range deviations during proton therapy. This study investigates the feasibility of using J-PET for range monitoring by means of a detailed Monte Carlo simulation study of 95 patients who underwent proton therapy at the Cyclotron Centre Bronowice (CCB) in Krakow, Poland. Approach: Discrepancies between prescribed and delivered treatments were artificially introduced in the simulations by means of shifts in patient positioning and in the Hounsfield unit to the relative proton stopping power calibration curve. A dual-layer, cylindrical J-PET geometry was simulated in an in-room monitoring scenario and a triple-layer, dual-head geometry in an in-beam protocol. The distribution of range shifts in reconstructed PET activity was visualised in the beam's eye view. Linear prediction models were constructed from all patients in the cohort, using the mean shift in reconstructed PET activity as a predictor of the mean proton range deviation. Main results: Maps of deviations in the range of reconstructed PET distributions showed agreement with those of deviations in dose range in most patients. The linear prediction model showed a good fit, with coefficient of determination r^2 = 0.84 (in-room) and 0.75 (in-beam). Residual standard error was below 1 mm: 0.33 mm (in-room) and 0.23 mm (in-beam). Significance: The precision of the proposed prediction models shows the sensitivity of the proposed J-PET scanners to shifts in proton range for a wide range of clinical treatment plans. Furthermore, it motivates the use of such models as a tool for predicting proton range deviations and opens up new prospects for investigations into the use of intra-treatment PET images for predicting clinical metrics that aid in the assessment of the quality of delivered treatment. .
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BACKGROUND: Dyslipidemia is one of the most important risk factors for atherosclerotic disease and may lead to coronary heart disease, obesity, type II diabetes and certain cancers. The choice of food and meals by adults is a large part determined by the dietary habits and knowledge acquired in earlier periods of life. OBJECTIVE: The aim of this study was to evaluate frequency of consumption of food products containing fats among students of the Catering School in Kraków. MATERIAL AND METHODS: The study was conducted with the participation of 140 students divided into two subgroups, depending on gender and age, in the autumn and winter season. During the studies a food frequency questionnaire containing question about frequency intake of selected groups of food products containing fats was used. This questionnaire was prepared at the Department of Human Nutrition Agricultural University of Kraków. RESULTS: A significant (P <0.05) effect of gender on preferences for the choice of milk, eating greasy food and the type of fat used for frying foods was found. Girls more often chose milk with reduced fat content compared to boys. It was observed that the fatty parts of food more often were eliminated by girls than boys. Girls more often than boys chose to fry foods oil or margarine, while boys more often used lard and bacon. Frequency of consumption offish or fish products, milk consumption preferences and eating fatty foods depended significantly (P <0.05) oon age. Older students less likely to eat the fish or fish products more often left fatty cuts compared to the younger students. Fatty milk was likely consumed by younger students, while fat free milk by older youth. CONCLUSIONS: It was found that the students of the Catering School, despite the acquired knowledge of nutrition, make many mistakes.