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1.
J Matern Fetal Neonatal Med ; 37(1): 2375015, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38977392

RESUMO

BACKGROUND: The mitigation measures implemented to face the healthcare emergency brought by COVID 19 pandemic generated an increase in socioeconomic inequities in the most underprivileged population which is also the most threatened in their human rights. In Uruguay, this population is assisted in the public health care system. To analyze how these measures impacted on these mothers and their neonates we selected outcomes that most contributed to neonatal mortality. OBJECTIVE: To analyze the incidence of Preterm Birth (PB), Intrauterine Growth Restriction (IUGR) and Low Birth Weight (LBW) in the public health care system in Uruguay, during the period of time in which the strictest measures were adopted to mitigate the COVID 19 pandemic in 2020 (para-pandemic period) compared to the same period in 2019 (pre-pandemic). METHODS: A retrospective, cross sectional, descriptive study was performed to compare PB, IUGR and LBW from 15 March to 30 September 2019 (before COVID 19 pandemic) to the same period of 2020 (when COVID 19 pandemic bloomed), in the public health care subsystem. The analysis was performed with data from the national perinatal database system (SIP). RESULTS: In 2020, a significative increase in PB, RR: 1.14 (CI 95%: 1.03-1.25), and in LBW, RR: 1.16 (CI 95% 1.02-1.33), was registered compared to 2019 (pre-pandemic period). IUGR also showed an increase, but without statistical significance (4.6% in 2019 vs 5.2% in 2020, RR 1.13 CI 95% 0.98-1.31). The compared groups showed no differences in the distribution of biological confounding variables that could explain the increase in incidence of the main outcomes. CONCLUSIONS: In the absence of other factors that could explain the results we consider that social crisis associated to the restrictive measures implemented in the country to dwindle the effect of the pandemic exacerbated the adverse conditions that affect the reproductive process for those underprivileged women assisted in the public sector, increasing PB and LBW. It is important to consider the future impact of these results on neonatal and infant mortality and to implement social measures to reduce the damage as soon as possible.


Assuntos
COVID-19 , Recém-Nascido de Baixo Peso , Nascimento Prematuro , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Feminino , Recém-Nascido , Nascimento Prematuro/epidemiologia , Estudos Retrospectivos , Gravidez , Estudos Transversais , Uruguai/epidemiologia , Adulto , Fatores Socioeconômicos , Retardo do Crescimento Fetal/epidemiologia , SARS-CoV-2 , Incidência
2.
ESMO Open ; 9(6): 103592, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38878323

RESUMO

BACKGROUND: Osimertinib represents the standard of care for the treatment of advanced non-small-cell lung cancer (NSCLC) harboring classical epidermal growth factor receptor (EGFR) mutations, constituting 80%-90% of all EGFR alterations. In the remaining cases, an assorted group of uncommon alterations of EGFR (uEGFR) can be detected, which confer variable sensitivity to previous generations of EGFR inhibitors, overall with lower therapeutic activity. Data on osimertinib in this setting are limited and strongly warranted. PATIENTS AND METHODS: The ARTICUNO study retrospectively evaluated data on osimertinib activity from patients with advanced NSCLC harboring uEGFR treated in 21 clinical centers between August 2017 and March 2023. Data analysis was carried out with a descriptive aim. Investigators collected response data according to RECIST version 1.1 criteria. The median duration of response, progression-free survival (mPFS), and overall survival were estimated by the Kaplan-Meier method. RESULTS: Eighty-six patients harboring uEGFR and treated with osimertinib were identified. Patients with 'major' uEGFR, that is, G719X, L861X, and S768I mutations (n = 51), had an overall response rate (ORR) and mPFS of 50% and 9 months, respectively. Variable outcomes were registered in cases with rarer 'minor' mutations (n = 27), with ORR and mPFS of 31% and 4 months, respectively. Among seven patients with exon 20 insertions, ORR was 14%, while the best outcome was registered among patients with compound mutations including at least one classical EGFR mutation (n = 13). Thirty patients presented brain metastases (BMs) and intracranial ORR and mPFS were 58% and 9 months, respectively. Amplification of EGFR or MET, TP53 mutations, and EGFR E709K emerged after osimertinib failure in a dataset of 18 patients with available rebiopsy. CONCLUSION: The ARTICUNO study confirms the activity of osimertinib in patients with uEGFR, especially in those with compound uncommon-common mutations, or major uEGFR, even in the presence of BMs. Alterations at the E709 residue of EGFR are associated with resistance to osimertinib.


Assuntos
Acrilamidas , Compostos de Anilina , Carcinoma Pulmonar de Células não Pequenas , Receptores ErbB , Neoplasias Pulmonares , Mutação , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Estudos Retrospectivos , Acrilamidas/uso terapêutico , Acrilamidas/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Receptores ErbB/genética , Compostos de Anilina/uso terapêutico , Compostos de Anilina/farmacologia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Adulto , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Inibidores de Proteínas Quinases/farmacologia , Indóis , Pirimidinas
3.
Phys Med ; 118: 103201, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38199179

RESUMO

PURPOSE: This work aims at studying the sensitivity of a miniaturized Tissue-Equivalent Proportional Counter to variations of beam quality in clinical radiation fields, to further investigate its performances as radiation quality monitor. METHODS: Measurements were taken at the CATANA facility (INFN-LNS, Catania, Italy), in a monoenergetic and an energy-modulated proton beam with the same initial energy of 62 MeV. PMMA layers were placed in front of the detector to measure at different depths along the depth-dose profile. The frequency- and dose-mean lineal energy were compared to the track- and dose-averaged LET calculated by Monte Carlo simulations. A microdosimetric evaluation of the Relative Biological Effectiveness (RBE) was performed and compared with cell survival experiments. RESULTS: Microdosimetric distributions measured at identical depths in the two beams show spectral differences reflecting their different radiation quality. Discrepancies are most evident at depths corresponding to the Spread-Out Bragg Peak, while spectra at the entrance and in the dose fall-off regions are similar. This can be explained by the different energy components that compose the pristine and spread-out peaks at each depth. The trend of microdosimetric mean values matches that of calculated LET averages along the entire penetration depth, and the microdosimetric estimation of RBE is consistent with radiobiological data not only at 2 Gy but also at lower dose levels, such as those absorbed by healthy tissues. CONCLUSIONS: The mini-TEPC is sensitive to differences in radiation quality resulting from different modulations of the proton beam, confirming its potential for beam quality monitoring in proton therapy.


Assuntos
Terapia com Prótons , Monitoramento de Radiação , Prótons , Radiometria/métodos , Eficiência Biológica Relativa , Método de Monte Carlo
4.
Radiat Prot Dosimetry ; 199(15-16): 1968-1972, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37819306

RESUMO

In proton therapy, most treatment planning systems (TPS) use a fixed relative biological effectiveness (RBE) of 1.1 all along the depth-dose profile. Innovative TPS are now investigated considering the variability of RBE with radiation quality. New TPS need an experimental verification in the quality assurance (QA) routine in clinics, but RBE data are usually obtained with radiobiological measurements that are time consuming and not suitable for daily QA. Microdosimetry is a useful tool based on physical measurements which can monitor the radiation quality. Several microdosimeters are available in different research institutions, which could potentially be used for the QA in TPS. In this study, the response functions of five detectors in the same 62-MeV proton Spread Out Bragg Peak is compared in terms of spectral distributions and their average values and microdosimetric RBE. Their different response function has been commented and must be considered in the clinical practice.


Assuntos
Terapia com Prótons , Prótons , Radiometria , Eficiência Biológica Relativa
5.
Radiat Prot Dosimetry ; 199(15-16): 1979-1983, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37819318

RESUMO

Proton-therapy exploits the advantageous depth-dose profile of protons to induce the highest damage to tumoral cells in the last millimetres of their range in sharp Bragg Peak. To cover the whole tumoral volume, beams of different energies are combined to create the Spread Out Bragg Peak (SOBP). In passive modulated beams, the energy spread is created with modulators in which the highest energy beam is degraded through different thicknesses of calibrated plastic materials. The highest energy is chosen depending on the deepest point that needs to be treated. This study aims to investigate differences in the radiation quality in the distal edge of SOBP beams with different initial energy and modulation techniques based on microdosimetric measurements with mini Tissue-Equivalent Proportional Counters. The beams investigated are the 62 MeV proton SOBP of the clinical facility of CATANA and the 148 MeV proton SOBP of the research beam line of the proton-therapy centre of Trento.


Assuntos
Terapia com Prótons , Prótons , Radiometria/métodos
6.
Phys Rev Lett ; 131(4): 041403, 2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37566847

RESUMO

In this Letter, we present the design and performance of the frequency-dependent squeezed vacuum source that will be used for the broadband quantum noise reduction of the Advanced Virgo Plus gravitational-wave detector in the upcoming observation run. The frequency-dependent squeezed field is generated by a phase rotation of a frequency-independent squeezed state through a 285 m long, high-finesse, near-detuned optical resonator. With about 8.5 dB of generated squeezing, up to 5.6 dB of quantum noise suppression has been measured at high frequency while close to the filter cavity resonance frequency, the intracavity losses limit this value to about 2 dB. Frequency-dependent squeezing is produced with a rotation frequency stability of about 6 Hz rms, which is maintained over the long term. The achieved results fulfill the frequency dependent squeezed vacuum source requirements for Advanced Virgo Plus. With the current squeezing source, considering also the estimated squeezing degradation induced by the interferometer, we expect a reduction of the quantum shot noise and radiation pressure noise of up to 4.5 dB and 2 dB, respectively.

7.
Artigo em Inglês | MEDLINE | ID: mdl-37506005

RESUMO

Software programming is an acquired evolutionary skill originating from consolidated cognitive functions (i.e., attentive, logical, coordination, mathematic calculation, and language comprehension), but the underlying neurophysiological processes are still not completely known. In the present study, we investigated and compared the brain activities supporting realistic programming, text and code reading tasks, analyzing Electroencephalographic (EEG) signals acquired from 11 experienced programmers. Multichannel spectral analysis and a phase-based effective connectivity study were carried out. Our results highlighted that both realistic programming and reading tasks are supported by modulations of the Theta fronto-parietal network, in which parietal areas behave as sources of information, while frontal areas behave as receivers. Nevertheless, during realistic programming, both an increase in Theta power and changes in network topology emerged, suggesting a task-related adaptation of the supporting network system. This reorganization mainly regarded the parietal area, which assumes a prominent role, increasing its hub functioning and its connectivity in the network in terms of centrality and degree.


Assuntos
Encéfalo , Eletroencefalografia , Humanos , Encéfalo/fisiologia , Eletroencefalografia/métodos , Cognição , Atenção/fisiologia , Software , Mapeamento Encefálico/métodos
12.
Int J Oral Maxillofac Surg ; 52(6): 686-690, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36220684

RESUMO

Transverse maxillomandibular hypoplasia can be treated with surgically assisted rapid maxillary expansion (SARME) in association with mandibular symphyseal distraction (MSD). This paper introduces a hybrid mandibular Bologna midline distractor (BMD); the effectiveness of the distractor in combination with SARME for the treatment of transverse skeletal deficiency was evaluated. This two-centre study included 10 patients with a transverse arch width deficit>7 mm and dental crowding, in both the maxilla and mandible, treated with SARME and MSD. The study design was partly retrospective (seven patients) and partly prospective (three patients). Frontal and lateral cephalometric analyses, as well as measurements on dental models, were performed at three different times: before treatment, after the distraction, and 6 months after postoperative orthodontic treatment. The cephalometric analyses and measurements on dental impressions confirmed a balanced and stable skeletal and dental mandibular expansion. An average symphyseal expansion of 7.8 mm was obtained, resolving dental crowding without dental extractions. In conclusion, mandibular expansion performed with the BMD in combination with SARME appears to be a viable surgical approach to transverse maxillomandibular hypoplasia. This technique allows the surgeon to obtain a balanced skeletal and dental expansion, with a low level of relapse.


Assuntos
Mandíbula , Técnica de Expansão Palatina , Dente , Estudos Prospectivos , Estudos Retrospectivos , Mandíbula/cirurgia , Cefalometria
13.
ESMO Open ; 7(6): 100597, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36208497

RESUMO

Oligometastatic prostate cancer (omPCa) is a novel intermediate disease state characterized by a limited volume of metastatic cells and specific locations. Accurate staging is paramount to unmask oligometastatic disease, as provided by prostate-specific membrane antigen-positron emission tomography. Driven by the results of prospective trials employing conventional and/or modern staging modalities, the treatment landscape of omPCa has rapidly evolved over the last years. Several treatment-related questions comprising the concept of precision strikes are under development. For example, beyond systemic therapy, cohort studies have found that cytoreductive radical prostatectomy (CRP) can confer a survival benefit in select patients with omPCa. More importantly, CRP has been consistently shown to improve long-term local symptoms when the tumor progresses across disease states due to resistance to systemic therapies. Metastasis-directed treatments have also emerged as a promising treatment option due to the visibility of oligometastatic disease and new technologies as well as treatment strategies to target the novel PCa colonies. Whether metastases are present at primary cancer diagnosis or detected upon biochemical recurrence after treatment with curative intent, targeted yet decisive elimination of disseminated tumor cell hotspots is thought to improve survival outcomes. One such strategy is salvage lymph node dissection in oligorecurrent PCa which can alter the natural history of progressive PCa. In this review, we will highlight how refinements in modern staging modalities change the classification and treatment of (oligo-)metastatic PCa. Further, we will also discuss the current role and future directions of precision surgery in omPCa.


Assuntos
Neoplasias da Próstata , Masculino , Humanos , Estudos Prospectivos , Neoplasias da Próstata/cirurgia , Próstata , Prostatectomia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos
14.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 4044-4047, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-36085986

RESUMO

When deciding how to pre-process EEG data, researchers need to make a choice at each single step of the procedure among different possibilities, equally valid. Therefore, in this work, we illustrate how these decisions may affect the quality of the final cleaned data in an Action Observation/Motor Imagery protocol, using quantitative indices. In particular, we showed the effect of segmenting or not the data in epochs around the stimulus presentation time on the independent component analysis (ICA) used for artifact removal. For ICA analysis, we tested two algorithms (SOBI and Extended Infomax). Finally, three re-reference approaches (Common averaged reference-CAR, robust-CAR and reference electrode standardization technique - REST) were also applied and their effects compared. Results showed that the segmenting method has a prominent effect on the cleaning procedure and consequently on final EEG data quality. Extended Infomax is confirmed as the method of choice for the identification of the artifactual components and, finally, CAR and the REST re-referencing techniques led to similar good results.


Assuntos
Eletroencefalografia , Processamento de Sinais Assistido por Computador , Algoritmos , Artefatos , Eletroencefalografia/métodos
15.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 2310-2313, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-36086042

RESUMO

The study of local field potentials (LFP) recorded from the basal ganglia of patients with movement disorders led to significant advancement in the understanding the pathophysiology of Parkinson's disease (PD). The possibility of investigating possible changes in the activity of the brain caused by the levodopa administration may provide a useful tool to evaluate the influence or the side-effects of the treatment from patient to patient. The analysis was carried out through a systematic analysis of the fractal component of the subthalamic local field potentials (STN-LFP) that may reveal, with respect to the classical power spectrum analysis, novel important information about the dynamic modulation caused by the drug intake. Indeed, so far, much of what is known about that is related to the presence of a spectral peak in the beta frequency band then attenuated after the levodopa administration. The nonlinear power-law exponent goes beyond this feature, exploring differences that reflect the fractal (scale-free) behavior of the PD brain dynamics. Here, in order to demonstrate that the presence or absence of the peak has no effect on the computation of the power-law exponent, we used simulated LFP recordings. After that, we performed the fractal analysis in shorts epochs of STN LFPs recordings ( N=24 patients, 12 females and 12 males) before and after Levodopa administration. We found no differences in the nonlinear power-law exponent for simulated data, reinforcing the idea that the parameter was not influenced by the attenuation of the hallmark peak for PD patients. As regard real LFP time series, we found that pharmacological treatment for PD differently altered LFP power of non-oscillatory activity, as well as changed the level of fractal exponent in specific frequency bands. Particularly we observed an increase of the fractal exponent in condition of post-levodopa with significant differences related to the response to levodopa in Parkinson's disease. Clinical Relevance- This study points out a potentially novel non-oscillatory biomarker which could reflect intrinsic properties of complex biological systems thus constituting a potential target parameter for novel and alternative neuroprosthetic applications.


Assuntos
Estimulação Encefálica Profunda , Doença de Parkinson , Núcleo Subtalâmico , Gânglios da Base , Estimulação Encefálica Profunda/métodos , Feminino , Humanos , Levodopa/farmacologia , Levodopa/uso terapêutico , Masculino , Núcleo Subtalâmico/fisiologia
16.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 4809-4812, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-36086203

RESUMO

Action Observation Therapy (AOT) is a rehabilitation method which aims at stimulating motor memory by means of the repetitive observation of motor tasks presented through video-clips. Since sleep seems to have a positive effect on learning processes, it is reasonable to hypothesize that the delivery of AOT immediately before sleep hours could enhance the effects of motor training. The objective of the present work was to test the effect of AOT delivered before the sleep hours in terms of improvements in manual dexterity and changes in cortical activity through Electroencephalography (EEG) on healthy subjects. Specifically, EEG traces acquired on a treatment and on a control group before and after three weeks of training during the execution of a Nine Hole Peg Test were analyzed. The spectral analysis of brain signals showed an increased activation of the motor cortex on a subgroup of the treatment subjects. Moreover, a significantly higher involvement of frontal areas was observed in the treatment group.


Assuntos
Eletroencefalografia , Córtex Motor , Encéfalo/fisiologia , Humanos , Aprendizagem/fisiologia , Sono
17.
Updates Surg ; 74(4): 1271-1279, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35606625

RESUMO

Despite operative benefit and oncological non-inferiority, videolaparoscopic (VLS) colorectal surgery is still relatively underutilized. This study analyzes the results of a program for the implementation of VLS colorectal surgery started in an Italian comprehensive cancer center shortly before COVID-19 outbreak. A prospective database was reviewed. The study period was divided in four phases: Phase-1 (Open surgery), Phase-2 (Discretional phase), Phase-3 (VLS implementation phase), and Phase-4 (VLS consolidation phase). Formal surgical and perioperative protocols were adopted from Phase-3. Postoperative complications were scored by the Clavien-Dindo classification. 414 surgical procedures were performed during Phase-1, 348 during Phase-2, 360 during Phase-3, and 325 during Phase-4. In the four phases, VLS primary colorectal resections increased from 11/214 (5.1%), to 55/163 (33.7%), 85/151 (57.0%), and 109/147 (74.1%), respectively. The difference was statistically significant (P < 0.001). All-type VLS procedures were 16 (3.5%), 61 (16.2%), 103 (27.0%), and 126 (38.6%) (P < 0.001). Conversions to open surgery of attempted laparoscopic colorectal resections were 17/278 in the overall series (6.1%), and 12/207 during Phase-3 and Phase-4 (4.3%). Severe (grades IIIb-to-V) postoperative complications of VLS colorectal resections were 9.1% in Phase-1, 12.7% in Phase-2, 12.8% in Phase-3, and 5.3% in Phase-4 (P = 0.677), with no significant differences with open resections in each of the four phases: 9.4% (P = 0.976), 11.1% (P = 0.799), 13.8% (P = 1.000), and 8.3% (P = 0.729). Despite the difficulties deriving from the COVID-19 outbreak, our experience suggests that volume of laparoscopic colorectal surgery can be significantly and safely increased in a specialized surgical unit by means of strict operative protocols.


Assuntos
COVID-19 , Neoplasias Colorretais , Cirurgia Colorretal , Laparoscopia , COVID-19/epidemiologia , Neoplasias Colorretais/complicações , Humanos , Laparoscopia/métodos , Pandemias , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos
18.
J Endocrinol Invest ; 45(8): 1535-1545, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35359232

RESUMO

OBJECTIVE: A comprehensive picture of pegvisomant use for treating acromegaly in routine clinical practice in different countries is lacking. We aimed, therefore, to document country-specific behaviors in real-life pegvisomant use, and the main safety and effectiveness outcomes in the ACROSTUDY. DESIGN: ACROSTUDY is an open-label, non-interventional, post-marketing safety surveillance study. METHODS: A descriptive analysis was performed using data from the six top-recruiter ACROSTUDY countries, i.e., Germany (n = 548 patients), Italy (n = 466), France (n = 312), USA (n = 207), Spain (n = 200) and the Netherlands (n = 175). These nations accounted for > 85% of the ACROSTUDY cases. RESULTS: The mean pegvisomant dose at treatment start was lowest in the Netherlands (9.4 mg/day), whereas it ranged between 10.9 and 12.6 mg/day in the other countries. At year 5, the mean pegvisomant dose was around 15 mg/day in all countries, except France (18.1 mg/day). At starting pegvisomant, patients treated with monotherapy ranged between 15% in the Netherlands and 72% in Spain. Monotherapy remained lowest over time in the Netherlands. In all countries, the percentage of patients with normal IGF-1 increased steeply from < 20% at baseline to 43-58% at month 6 and 51-67% at year 1. After that, we observed minor changes in the rate of acromegaly control in all countries. The Netherlands peaked in disease control at year 2 (72%). The proportion of patients reporting changes in pituitary tumor size was generally low. Serious treatment-related adverse events were < 5% in all countries. CONCLUSIONS: Our study provided a detailed summary of real-life use of pegvisomant in the six top-recruiter ACROSTUDY nations.


Assuntos
Acromegalia , Hormônio do Crescimento Humano , Neoplasias Hipofisárias , Acromegalia/induzido quimicamente , Acromegalia/tratamento farmacológico , Hormônio do Crescimento Humano/efeitos adversos , Hormônio do Crescimento Humano/análogos & derivados , Humanos , Fator de Crescimento Insulin-Like I , Neoplasias Hipofisárias/tratamento farmacológico , Receptores da Somatotropina
19.
Appl Radiat Isot ; 182: 110144, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35168037

RESUMO

The MUNES project (MUltidisciplinary NEutron Source) aims at the realization of an intense accelerator-based source of thermal neutrons, suitable for Boron Neutron Capture Therapy (BNCT). This exploits the interaction of 5 MeV protons onto a beryllium target, producing a fast neutron spectrum, which is moderated to the thermal range by a large assembly made of a Polytetrafluoroethylene (PTFE) tank filled with heavy water, surrounded by graphite blocks. The thermal neutron field is extracted through a bismuth beam port. The microdosimetric characterization of this field was performed using a cylindrical avalanche-confinement Tissue Equivalent Proportional Counter (TEPC) equipped with interchangeable cathode walls, positioned in front of the beam port. Measurements were taken both with a boron-doped wall and with an undoped one. The comparison of the two microdosimetric distributions allows to distinguish the relative dose contribution due to alpha particles and lithium ions from the BNC reaction from that of photons and other particles from neutron interactions on the cathode walls. The Relative Biological Effectiveness (RBE) was also calculated from the convolution of the measured spectra with a biological weighting function. This paper describes the experimental microdosimetric approach and the results of measurements with a boron-loaded cathode performed for the first time at an accelerator-based BNCT source.


Assuntos
Terapia por Captura de Nêutron de Boro , Nêutrons , Radiometria/métodos , Eficiência Biológica Relativa , Berílio , Boro/uso terapêutico , Nêutrons Rápidos , Humanos , Lítio , Aceleradores de Partículas , Prótons
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