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2.
Heliyon ; 10(9): e29772, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38720758

RESUMO

The pressing issue of atmospheric pollution has prompted the exploration of affordable methods for measuring and monitoring air contaminants as complementary techniques to standard methods, able to produce high-density data in time and space. The main challenge of this low-cost approach regards the in-field accuracy and reliability of the sensors. This study presents the development of low-cost stations for high-time resolution measurements of CO2 and CH4 concentrations calibrated via an in-field machine learning-based method. The calibration models were built based on measurements parallelly performed with the low-cost sensors and a CRDS analyzer for CO2 and CH4 as reference instrument, accounting for air temperature and relative humidity as external variables. To ensure versatility across locations, diversified datasets were collected, consisting of measurements performed in various environments and seasons. The calibration models, trained with 70 % for modeling, 15 % for validation, and 15 % for testing, demonstrated robustness with CO2 and CH4 predictions achieving R2 values from 0.8781 to 0.9827 and 0.7312 to 0.9410, and mean absolute errors ranging from 3.76 to 1.95 ppm and 0.03 to 0.01 ppm, for CO2 and CH4, respectively. These promising results pave the way for extending these stations to monitor additional air contaminants, like PM, NOx, and CO through the same calibration process, integrating them with remote data transmission modules to facilitate real-time access, control, and processing for end-users.

3.
Oral Oncol ; 152: 106744, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38520756

RESUMO

PURPOSE: In clinical practice the assessment of the "vocal cord-arytenoid unit" (VCAU) mobility is crucial in the staging, prognosis, and choice of treatment of laryngeal squamous cell carcinoma (LSCC). The aim of the present study was to measure repeatability and reliability of clinical assessment of VCAU mobility and radiologic analysis of posterior laryngeal extension. METHODS: In this multi-institutional retrospective study, patients with LSCC-induced impairment of VCAU mobility who received curative treatment were included; pre-treatment endoscopy and contrast-enhanced imaging were collected and evaluated by raters. According to their evaluations, concordance, number of assigned categories, and inter- and intra-rater agreement were calculated. RESULTS: Twenty-two otorhinolaryngologists evaluated 366 videolaryngoscopies (total evaluations: 2170) and 6 radiologists evaluated 237 imaging studies (total evaluations: 477). The concordance of clinical rating was excellent in only 22.7% of cases. Overall, inter- and intra-rater agreement was weak. Supraglottic cancers and transoral endoscopy were associated with the lowest inter-observer reliability values. Radiologic inter-rater agreement was low and did not vary with imaging technique. Intra-rater reliability of radiologic evaluation was optimal. CONCLUSIONS: The current methods to assess VCAU mobility and posterior extension of LSCC are flawed by weak inter-observer agreement and reliability. Radiologic evaluation was characterized by very high intra-rater agreement, but weak inter-observer reliability. The relevance of VCAU mobility assessment in laryngeal oncology should be re-weighted. Patients affected by LSCC requiring imaging should be referred to dedicated radiologists with experience in head and neck oncology.


Assuntos
Neoplasias Laríngeas , Prega Vocal , Humanos , Neoplasias Laríngeas/diagnóstico por imagem , Neoplasias Laríngeas/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Prega Vocal/diagnóstico por imagem , Prega Vocal/fisiopatologia , Adulto , Reprodutibilidade dos Testes , Idoso de 80 Anos ou mais , Laringoscopia/métodos , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/patologia
4.
J Hosp Infect ; 142: 9-17, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37797656

RESUMO

BACKGROUND: The aim of this study was to estimate the incidence, associated disease burden and healthcare utilization due to Staphylococcus aureus prosthetic joint infections (SA-PJI) after primary hip and knee arthroplasty in European centres. METHODS: This study was conducted in patients who underwent primary hip and knee arthroplasty in 19 European hospitals between 2014 and 2016. The global incidence of PJI and SA-PJI was calculated. The associated disease burden was measured indirectly as infection-related mortality plus loss of function. For healthcare utilization, number and duration of hospitalizations, number and type of surgical procedures, duration of antibiotic treatments, and number of outpatient visits were collected. Subgroup and regression analyses were used to evaluate the impact of SA-PJI on healthcare utilization, controlling for confounding variables. RESULTS: The incidence of PJI caused by any micro-organism was 1.41%, and 0.40% for SA-PJI. Among SA-PJI, 20.7% were due to MRSA with substantial regional differences, and were more frequent in partial hip arthroplasty (PHA). Related deaths and loss of function occurred in 7.0% and 10.2% of SA-PJI cases, respectively, and were higher in patients with PHA. Compared with patients without PJI, patients with SA-PJI had a mean of 1.4 more readmissions, 25.1 more days of hospitalization, underwent 1.8 more surgical procedures, and had 5.4 more outpatient visits, controlling for confounding variables. Healthcare utilization was higher in patients who failed surgical treatment of SA-PJI. CONCLUSIONS: This study confirmed that the SA-PJI burden is high, especially in PHA, and provided a solid basis for planning interventions to prevent SA-PJI.


Assuntos
Artroplastia de Quadril , Infecções Relacionadas à Prótese , Infecções Estafilocócicas , Humanos , Staphylococcus aureus , Incidência , Infecções Relacionadas à Prótese/epidemiologia , Infecções Relacionadas à Prótese/etiologia , Estudos Retrospectivos , Artroplastia de Quadril/efeitos adversos , Infecções Estafilocócicas/epidemiologia , Hospitais , Aceitação pelo Paciente de Cuidados de Saúde , Efeitos Psicossociais da Doença
6.
BMC Med ; 19(1): 2, 2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-33397366

RESUMO

BACKGROUND: Through a combination of strong routine immunization (RI), strategic supplemental immunization activities (SIA) and robust surveillance, numerous countries have been able to approach or achieve measles elimination. The fragility of these achievements has been shown, however, by the resurgence of measles since 2016. We describe trends in routine measles vaccine coverage at national and district level, SIA performance and demographic changes in the three regions with the highest measles burden. FINDINGS: WHO-UNICEF estimates of immunization coverage show that global coverage of the first dose of measles vaccine has stabilized at 85% from 2015 to 19. In 2000, 17 countries in the WHO African and Eastern Mediterranean regions had measles vaccine coverage below 50%, and although all increased coverage by 2019, at a median of 60%, it remained far below levels needed for elimination. Geospatial estimates show many low coverage districts across Africa and much of the Eastern Mediterranean and southeast Asian regions. A large proportion of children unvaccinated for MCV live in conflict-affected areas with remote rural areas and some urban areas also at risk. Countries with low RI coverage use SIAs frequently, yet the ideal timing and target age range for SIAs vary within countries, and the impact of SIAs has often been mitigated by delays or disruptions. SIAs have not been sufficient to achieve or sustain measles elimination in the countries with weakest routine systems. Demographic changes also affect measles transmission, and their variation between and within countries should be incorporated into strategic planning. CONCLUSIONS: Rebuilding services after the COVID-19 pandemic provides a need and an opportunity to increase community engagement in planning and monitoring services. A broader suite of interventions is needed beyond SIAs. Improved methods for tracking coverage at the individual and community level are needed together with enhanced surveillance. Decision-making needs to be decentralized to develop locally-driven, sustainable strategies for measles control and elimination.


Assuntos
Erradicação de Doenças , Programas de Imunização , Imunização Secundária , Sarampo , Regionalização da Saúde/organização & administração , Cobertura Vacinal/tendências , África/epidemiologia , Sudeste Asiático/epidemiologia , COVID-19/epidemiologia , COVID-19/prevenção & controle , Criança , Erradicação de Doenças/métodos , Erradicação de Doenças/estatística & dados numéricos , Humanos , Programas de Imunização/métodos , Programas de Imunização/organização & administração , Imunização Secundária/métodos , Imunização Secundária/estatística & dados numéricos , Sarampo/epidemiologia , Sarampo/prevenção & controle , Vacina contra Sarampo/uso terapêutico , Região do Mediterrâneo/epidemiologia , SARS-CoV-2
7.
Public Health ; 190: 16-22, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33326889

RESUMO

OBJECTIVE: To examine the prevalence, and the demographic, socio-economic, and health correlates to Outdoor Gyms (OGs) use for adults from a southern Brazilian city. STUDY DESIGN: Population-based cross-sectional study. METHODS: A total of 431 adults (66.8% women) aged 18-87 years living in the surroundings of four OGs distributed in different regions of the city were randomly selected. Information about OG use for physical activity (PA) practice, and demographic, socio-economic, and health variables were collected by household interviews. Associations between independent variables and OG use were analyzed with results expressed as odds ratio (OR) and 95% confidence interval (95% CI). RESULTS: About one-third of participants (30.4%; 95% CI: 26.1-34.7) informed using OGs for PA practice, and 20.4% (95% CI 16.8-24.4) informed using it twice or more times a week (≥2x/week). Adjusted analysis indicated that the OG use ≥2x/week is higher for women (OR: 1.93; 95% CI: 1.11-3.35) and for those with lower family income (OR: 2.13; 95% CI: 1.03-4.13) than men and those with higher family income, respectively. CONCLUSION: About 30% of the population uses OGs for PA practice. Women and low-income people are those who more commonly use OGs for PA practice. The installation of these facilities in public spaces may reduce social inequities related to leisure-time PA.


Assuntos
Exercício Físico , Academias de Ginástica/estatística & dados numéricos , Pobreza , Características de Residência , Equipamentos Esportivos/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil , Cidades , Estudos Transversais , Planejamento Ambiental , Características da Família , Feminino , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Atividade Motora , Vigilância da População , Prevalência , Fatores Socioeconômicos , Adulto Jovem
8.
Epidemiol Infect ; 145(2): 227-235, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27760574

RESUMO

Measles was eliminated in the Americas in 2002 by a combination of routine immunizations and supplementary immunization activities. Recent outbreaks underscore the importance of reconsidering vaccine policy in order to maintain elimination. We constructed an age-structured dynamical model for the distribution of immunity in a population with routine immunization and without disease, and analysed the steady state for an idealized age structure and for real age structures of countries in the Americas. We compared the level of immunity maintained by current policy in these countries to the level maintainable by an optimal policy. The optimal age target for the first routine dose of measles vaccine depends on the timing and coverage of both doses. Similarly, the optimal age target for the second dose of measles vaccine depends on the timing and coverage of the first dose. The age targets for the first and second doses of measles vaccine should be adjusted for the post-elimination era, by specifically accounting for current context, including realized coverage of both doses, and altered maternal immunity. Doing so can greatly improve the proportion immune within a population, and therefore the chances of maintaining measles elimination, without changing coverage.


Assuntos
Erradicação de Doenças , Esquemas de Imunização , Vacina contra Sarampo/administração & dosagem , Sarampo/prevenção & controle , Adolescente , Adulto , Fatores Etários , Idoso , América/epidemiologia , Criança , Pré-Escolar , Feminino , Política de Saúde , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Adulto Jovem
9.
Phys Med ; 32(9): 1139-44, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27601248

RESUMO

PURPOSE: A radio-guided surgery technique with ß(-)-emitting radio-tracers was suggested to overcome the effect of the large penetration of γ radiation. The feasibility studies in the case of brain tumors and abdominal neuro-endocrine tumors were based on simulations starting from PET images with several underlying assumptions. This paper reports, as proof-of-principle of this technique, an ex vivo test on a meningioma patient. This test allowed to validate the whole chain, from the evaluation of the SUV of the tumor, to the assumptions on the bio-distribution and the signal detection. METHODS: A patient affected by meningioma was administered 300MBq of (90)Y-DOTATOC. Several samples extracted from the meningioma and the nearby Dura Mater were analyzed with a ß(-) probe designed specifically for this radio-guided surgery technique. The observed signals were compared both with the evaluation from the histology and with the Monte Carlo simulation. RESULTS: we obtained a large signal on the bulk tumor (105cps) and a significant signal on residuals of ∼0.2ml (28cps). We also show that simulations predict correctly the observed yields and this allows us to estimate that the healthy tissues would return negligible signals (≈1cps). This test also demonstrated that the exposure of the medical staff is negligible and that among the biological wastes only urine has a significant activity. CONCLUSIONS: This proof-of-principle test on a patient assessed that the technique is feasible with negligible background to medical personnel and confirmed that the expectations obtained with Monte Carlo simulations starting from diagnostic PET images are correct.


Assuntos
Neoplasias Encefálicas/radioterapia , Meningioma/radioterapia , Tomografia por Emissão de Pósitrons , Radiocirurgia/métodos , Cirurgia Assistida por Computador/métodos , Idoso , Algoritmos , Partículas beta , Neoplasias Encefálicas/diagnóstico por imagem , Simulação por Computador , Estudos de Viabilidade , Feminino , Humanos , Meningioma/diagnóstico por imagem , Modelos Teóricos , Método de Monte Carlo , Exposição Ocupacional/prevenção & controle , Octreotida/análogos & derivados , Octreotida/química , Radiometria , Reprodutibilidade dos Testes
10.
Med Klin Intensivmed Notfmed ; 111(7): 605-609, 2016 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-27279378

RESUMO

Adequate organ supply of oxygen and of nutrients depends on microcirculation. Impaired microcirculation may result in temporary or irreversible loss of function. Therefore, critically ill patients require early diagnosis and therapy of microcirculatory disorders. Besides surrogate parameters of microcirculation like urine production or serum lactate levels, direct visualization became possible with sidestream darkfield intravital microscopy. This technique has been evaluated in clinical studies focusing on early diagnosis and therapy in cardiogenic shock like vasopressors, nitrates, or circulatory assist devices. Further studies evaluating measurements of microcirculation are necessary before a general recommendation for its routine use can be made.


Assuntos
Estado Terminal , Microcirculação , Hemodinâmica , Humanos , Oxigênio , Choque Cardiogênico
11.
Phys Med Biol ; 58(22): 8099-120, 2013 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-24200697

RESUMO

Patient-specific absorbed dose calculation for nuclear medicine therapy is a topic of increasing interest. 3D dosimetry at the voxel level is one of the major improvements for the development of more accurate calculation techniques, as compared to the standard dosimetry at the organ level. This study aims to use the FLUKA Monte Carlo code to perform patient-specific 3D dosimetry through direct Monte Carlo simulation on PET-CT and SPECT-CT images. To this aim, dedicated routines were developed in the FLUKA environment. Two sets of simulations were performed on model and phantom images. Firstly, the correct handling of PET and SPECT images was tested under the assumption of homogeneous water medium by comparing FLUKA results with those obtained with the voxel kernel convolution method and with other Monte Carlo-based tools developed to the same purpose (the EGS-based 3D-RD software and the MCNP5-based MCID). Afterwards, the correct integration of the PET/SPECT and CT information was tested, performing direct simulations on PET/CT images for both homogeneous (water) and non-homogeneous (water with air, lung and bone inserts) phantoms. Comparison was performed with the other Monte Carlo tools performing direct simulation as well. The absorbed dose maps were compared at the voxel level. In the case of homogeneous water, by simulating 10(8) primary particles a 2% average difference with respect to the kernel convolution method was achieved; such difference was lower than the statistical uncertainty affecting the FLUKA results. The agreement with the other tools was within 3­4%, partially ascribable to the differences among the simulation algorithms. Including the CT-based density map, the average difference was always within 4% irrespective of the medium (water, air, bone), except for a maximum 6% value when comparing FLUKA and 3D-RD in air. The results confirmed that the routines were properly developed, opening the way for the use of FLUKA for patient-specific, image-based dosimetry in nuclear medicine.


Assuntos
Imageamento Tridimensional/métodos , Método de Monte Carlo , Imagem Multimodal/métodos , Tomografia por Emissão de Pósitrons/métodos , Medicina de Precisão/métodos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Tomografia Computadorizada por Raios X/métodos , Ar , Osso e Ossos/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Imagens de Fantasmas , Radiometria , Água
12.
Eur J Clin Nutr ; 67(7): 765-72, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23695206

RESUMO

BACKGROUND/OBJECTIVES: Adolescents are at risk of iron deficiency because of their high iron requirements. The aims of this study were: (1) to assess iron intake, its determinants and its most important food sources and; (2) to evaluate the relation of iron intake and status in European adolescents. SUBJECTS/METHODS: Two non-consecutive 24-h recalls were completed by a computerised tool. The socio-demographic and socio-economic data were collected by a self-reported questionnaire. Weight and height were measured. A distinction was made between haem and non-haem iron. RESULTS: The total iron intake was significantly higher among boys (13.8 mg/day; n=1077) than girls (11.0 mg/day; n=1253). About 97.3% of the boys and 87.8% of the girls met the estimated average requirement, and 72.4% of the boys and 13.7% of the girls met the recommendation for bio-available iron intake. The ratio of haem/non-haem iron intake was lower for girls than boys. Meat (19.2; 76%) and bread and rolls (12.6;3.9%) contributed most to total and haem iron intake. Bread and rolls (13.8%) and meat (10.8%) contributed most to non-haem iron intake. Age, sex and body mass index were associated with iron intake. Only red blood cell concentration was significantly negatively associated with total, haem and non-haem iron intake. CONCLUSION: Girls had lower iron intakes and ratio of haem/non-haem iron intake than boys. The main total iron and haem iron source was meat, while the main non-haem iron source was bread and rolls. Adolescent girls may be a group at risk for iron deficiency. Consequently, special attention and strategies are needed in order to improve iron intakes during adolescence.


Assuntos
Dieta , Heme/química , Ferro da Dieta/administração & dosagem , Ferro da Dieta/sangue , Estilo de Vida , Estado Nutricional , Adolescente , Índice de Massa Corporal , Peso Corporal , Pão , Criança , Análise por Conglomerados , Estudos Transversais , Ingestão de Energia , Europa (Continente) , Feminino , Humanos , Modelos Lineares , Masculino , Carne , Atividade Motora , Avaliação Nutricional , Fatores Socioeconômicos , Inquéritos e Questionários
13.
Int J Med Robot ; 9(4): 396-406, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23166047

RESUMO

BACKGROUND: The da Vinci robotic surgical telemanipulator has been utilized in several surgical specialties for varied procedures, and the users' experiences have been widely published. To date, no detailed system technical analyses have been performed. METHODS: A detailed review was performed of all publications and patents about the technical aspects of the da Vinci robotic system. RESULTS: Published technical literature on the da Vinci system highlight strengths and weaknesses of the robot design. While the system facilitates complex surgical operations and has a low malfunction rate, the lack of haptic (especially tactile) feedback and collisions between the robotic arms remain the major limitations of the system. Accurate, preplanned positioning of access ports is essential. CONCLUSION: Knowledge of the technical aspects of the da Vinci robot is important for optimal use. We confirmed the excellent system functionality and ease of use for surgeons without an engineering background. Research and development of the surgical robot has been predominant in the literature. Future trends address robot miniaturization and intelligent control design.


Assuntos
Robótica/instrumentação , Cirurgia Assistida por Computador/instrumentação , Telemedicina/instrumentação , Interface Usuário-Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Avaliação da Tecnologia Biomédica
14.
Pediatr Obes ; 8(5): 385-91, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23239558

RESUMO

BACKGROUND: Obesity and the metabolic syndrome are dramatically increasing problems. Red blood cell distribution width (RDW), the variability in size of circulating red blood cells, has been demonstrated to be altered in different clinical settings. This analysis aimed to investigate the relationship between RDW and obesity in adolescents and in an animal model of diet-induced obesity (DIO). METHODS: Seventy-nine male adolescents (aged 13-17 years) were studied. Thirty-seven of them were overweight (body mass index ≥ 90th percentile). RDW, markers of inflammation and stem cell factor (SCF) were determined. In an animal study, mice were fed with different diets for 15 weeks. RDW was determined using an animal blood count machine. RESULTS: RDW differed significantly between normal-weight adolescents (13.07 ± 0.09) and overweight adolescents (13.39 ± 0.10, P = 0.015), whereas erythrocyte counts and haematocrit did not differ. RDW correlated to markers of inflammation and inversely to SCF. In the mice animal model, nutritional changes increased RDW, whereas overweight per se did not change RDW. CONCLUSIONS: RDW is elevated in overweight and reflects the inflammatory state. RDW potentially represents an additional and cost-effective tool to indicate inflammation. Future studies are needed to understand the differential influences of nutrition and overweight on RDW.


Assuntos
Índices de Eritrócitos , Eritrócitos , Inflamação/sangue , Síndrome Metabólica/sangue , Sobrepeso/sangue , Adolescente , Animais , Biomarcadores/sangue , Circulação Coronária , Análise Custo-Benefício , Modelos Animais de Doenças , Eritrócitos/imunologia , Alemanha/epidemiologia , Humanos , Inflamação/epidemiologia , Inflamação/imunologia , Masculino , Síndrome Metabólica/epidemiologia , Síndrome Metabólica/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/sangue , Sobrepeso/epidemiologia , Sobrepeso/imunologia , Valor Preditivo dos Testes
15.
Science ; 334(6061): 1424-7, 2011 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-22158822

RESUMO

Measles epidemics in West Africa cause a significant proportion of vaccine-preventable childhood mortality. Epidemics are strongly seasonal, but the drivers of these fluctuations are poorly understood, which limits the predictability of outbreaks and the dynamic response to immunization. We show that measles seasonality can be explained by spatiotemporal changes in population density, which we measure by quantifying anthropogenic light from satellite imagery. We find that measles transmission and population density are highly correlated for three cities in Niger. With dynamic epidemic models, we demonstrate that measures of population density are essential for predicting epidemic progression at the city level and improving intervention strategies. In addition to epidemiological applications, the ability to measure fine-scale changes in population density has implications for public health, crisis management, and economic development.


Assuntos
Cidades , Métodos Epidemiológicos , Sarampo/epidemiologia , Densidade Demográfica , Estações do Ano , Emigração e Imigração , Epidemias , Humanos , Luz , Sarampo/transmissão , Níger/epidemiologia , Tecnologia de Sensoriamento Remoto , Astronave
16.
Med Phys ; 38(7): 3944-54, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21858991

RESUMO

PURPOSE: The calculation of patient-specific dose distribution can be achieved by Monte Carlo simulations or by analytical methods. In this study, FLUKA Monte Carlo code has been considered for use in nuclear medicine dosimetry. Up to now, FLUKA has mainly been dedicated to other fields, namely high energy physics, radiation protection, and hadrontherapy. When first employing a Monte Carlo code for nuclear medicine dosimetry, its results concerning electron transport at energies typical of nuclear medicine applications need to be verified. This is commonly achieved by means of calculation of a representative parameter and comparison with reference data. Dose point kernel (DPK), quantifying the energy deposition all around a point isotropic source, is often the one. METHODS: FLUKA DPKS have been calculated in both water and compact bone for monoenergetic electrons (10-3 MeV) and for beta emitting isotopes commonly used for therapy (89Sr, 90Y, 131I 153Sm, 177Lu, 186Re, and 188Re). Point isotropic sources have been simulated at the center of a water (bone) sphere, and deposed energy has been tallied in concentric shells. FLUKA outcomes have been compared to PENELOPE v.2008 results, calculated in this study as well. Moreover, in case of monoenergetic electrons in water, comparison with the data from the literature (ETRAN, GEANT4, MCNPX) has been done. Maximum percentage differences within 0.8.RCSDA and 0.9.RCSDA for monoenergetic electrons (RCSDA being the continuous slowing down approximation range) and within 0.8.X90 and 0.9.X90 for isotopes (X90 being the radius of the sphere in which 90% of the emitted energy is absorbed) have been computed, together with the average percentage difference within 0.9.RCSDA and 0.9.X90 for electrons and isotopes, respectively. RESULTS: Concerning monoenergetic electrons, within 0.8.RCSDA (where 90%-97% of the particle energy is deposed), FLUKA and PENELOPE agree mostly within 7%, except for 10 and 20 keV electrons (12% in water, 8.3% in bone). The discrepancies between FLUKA and the other codes are of the same order of magnitude than those observed when comparing the other codes among them, which can be referred to the different simulation algorithms. When considering the beta spectra, discrepancies notably reduce: within 0.9.X90, FLUKA and PENELOPE differ for less than 1% in water and less than 2% in bone with any of the isotopes here considered. Complete data of FLUKA DPKS are given as Supplementary Material as a tool to perform dosimetry by analytical point kernel convolution. CONCLUSIONS: FLUKA provides reliable results when transporting electrons in the low energy range, proving to be an adequate tool for nuclear medicine dosimetry.


Assuntos
Método de Monte Carlo , Neoplasias/fisiopatologia , Neoplasias/radioterapia , Radioisótopos/uso terapêutico , Radiometria/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Software , Algoritmos , Animais , Simulação por Computador , Elétrons , Humanos , Modelos Biológicos , Dosagem Radioterapêutica , Resultado do Tratamento
17.
Artigo em Inglês | MEDLINE | ID: mdl-20635267

RESUMO

The assessment of acute and chronic dietary exposure to contaminants in baby foods is needed to ensure healthy infant growth. Monthly European Union market baskets of commercial baby foods were designed for the first 9 months of life by the 'babyfood' study group of the CASCADE Network of Excellence for the specific purpose of assessing exposure to potentially toxic substances in infants fed with such foods. The present paper reports the different steps that led to the preparation of monthly pooled samples of commercial baby foods ('Infant formulae and follow-on formulae' and 'Other baby foods') that may constitute the extreme case of the diet for an infant who would not be breast fed at all. Several market baskets were generated for an 'average European Union infant' and for infants of four selected countries (Italy, Sweden, Spain, and the Slovakia), fed with either milk infant formulae, soy infant formulae or hypoallergenic infant formulae and weaned (at the fifth month) with commercial baby foods and beverages available on the European Union market. Market share data for 2007 for baby foods were used to design the baskets. Holding companies and the name of all their products were identified. Monthly diets for European Union infants were elaborated in terms of food categories (e.g. infant cereals) of typologies of products (e.g. infant cereals without gluten) and of a specific product. The number of baskets generated was 30 for 'Infant formulae and follow-on formulae' (including 62 products) and 13 for 'Other baby foods' (including 35 products). These market baskets were designed to be used for the determination of certain contaminants and nutrients in the diet of European Union infants and for the assessment of their effects on infant health.


Assuntos
Contaminação de Alimentos/análise , Alimentos Infantis/análise , Animais , Peso Corporal , Ingestão de Energia , Exposição Ambiental , União Europeia , Manipulação de Alimentos/métodos , Humanos , Lactente , Alimentos Infantis/efeitos adversos , Fórmulas Infantis/química , Fenômenos Fisiológicos da Nutrição do Lactente , Leite , Necessidades Nutricionais , Leite de Soja
18.
Transpl Infect Dis ; 11(6): 491-6, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19664021

RESUMO

Infection or reactivation of human herpesvirus (HHV)-6 represents a potentially serious complication (often involving the central nervous system) in patients receiving either solid organ or hematopoietic stem cell transplantation. The objective of this study was to assess the risk of HHV-6 infection/reactivation in mesenchymal stromal cells (MSCs). MSCs are multipotent cells displaying immunomodulatory properties that have been already successfully used in the clinical setting to enhance hematopoietic stem cell engraftment and to treat steroid-refractory acute graft-versus-host disease. We analyzed 20 samples of ex vivo expanded MSCs, at different passages of culture, isolated both from bone marrow and from umbilical cord blood. Through Western blotting and immunocytochemistry techniques, we investigated the presence of the HHV-6 receptor (CD46) on cell surface, whereas the presence of HHV-6 DNA was evaluated by nested polymerase chain reaction assay. All of the MSC samples tested were positive for the virus receptor (CD46), suggesting their potential susceptibility to HHV-6. However, none of the MSC samples derived from cultures, performed in the perspective of clinical use, was found to harbor HHV-6. This preliminary observation on a consistent number of MSC samples, some of them tested at late in vitro passages, indicates a good safety profile of the product in terms of HHV-6 contamination. Nevertheless, it remains important to set up in vitro experimental models to study MSCs' susceptibility to HHV-6 (and HHV-7) infection, to verify their capacity to integrate the virus into cellular DNA, and to investigate which experimental conditions are able to induce virus reactivation.


Assuntos
Herpesvirus Humano 6/isolamento & purificação , Células-Tronco Mesenquimais/virologia , Infecções por Roseolovirus/diagnóstico , Animais , Western Blotting , Linhagem Celular Tumoral , DNA Viral/análise , DNA Viral/isolamento & purificação , Sangue Fetal/citologia , Herpesvirus Humano 6/genética , Herpesvirus Humano 6/metabolismo , Humanos , Imuno-Histoquímica , Proteína Cofatora de Membrana/metabolismo , Células-Tronco Mesenquimais/metabolismo , Camundongos , Reação em Cadeia da Polimerase/métodos , Infecções por Roseolovirus/virologia
19.
Med Intensiva ; 32(9): 411-8, 2008 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-19080863

RESUMO

OBJECTIVE: To assess early pituitary function in a sequential cohort of critical care patients after severe traumatic brain injury (TBI). DESIGN: This was a prospective observational study. The pituitary function was always tested on the third day after TBI. SETTING: Neurocritical intensive care unit (ICU) in a University hospital. PATIENTS: A total of 136 adult patients with severe TBI (range, 16-65 years) enrolled over a 2 year and 9 month period having a stay in the ICU treated than 48 hours. INTERVENTION: None. MEASUREMENTS AND DATA COLLECTED: The following data were recorded within the first 72 hours after injury: demographic variables, injury severity, neuromonitoring data, systemic secondary brain insults, use of vasoactive drugs and type of TBI according to the computerized tomography (CT) scan findings. Pituitary function was evaluated by measurement of both the pituitary and target organ hormones, with the exception of the somatotrophic function, which was assessed by measurement of basal serum values of insulin-like growth factor-I (IGF-I). RESULTS: Pituitary dysfunction was observed in 101 patients (74.2%). Seventy-nine patients (58%) had impairment of only one pituitary axis, the axes being affected as follows: gonadotropic 63.7% (87 patients), thyrotropic 8.8% (12 patients) and corticotropic 0.7% (1 patient). Low IGF-1 plasmatic levels in accordance to the patient's age were observed in 90 patients (66.7%). However, only 26 of them had a value below 90 ng/ml. CONCLUSIONS: Our data show that pituitary dysfunction occurs early and with high frequency after severe TBI, but the real significance of these findings still needs to be elucidated.


Assuntos
Traumatismos Craniocerebrais/fisiopatologia , Sistema Hipotálamo-Hipofisário/fisiopatologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Escala de Gravidade do Ferimento , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
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