Gamma knife radiosurgery for vestibular schwannomas: evaluation of planning using the sphericity degree of the target volume

This study explores the possibility of a relationship between the sphericity degree of a target volume with the dose distribution. This relationship is evaluated based on the ratio isodose volume / target volume (IV/TV) and the metrics coverage, i.e., selectivity, gradient index, conformity index and mean dose when planning radiosurgery for vestibular schwannoma. Methods: Sphericity degree (φ) was calculated for each target volume (TV) of 64 patients who underwent stereotactic radiosurgery (SRS) for vestibular schwannoma. The calculation of this parameter was developed using the theoretical definition for operational sphericity φ = VP/VCS. The values found are evaluated considering the following metrics:-Coverage (C), selectivity (S), gradient index (GI), Paddick conformity index (CIPaddick) and dose distribution (IV/TV). The planning was also carried out considering a spherical target volume defined in a spherical phantom. The spherical volume is the same as the target used in the treatment plan. The planning of the spherical target was considered as a reference plan to evaluate the dose distribution inside and outside the volume. Results: It was possible to observe that the majority of target volumes has (.) around 0,66.0,77, corresponding to 54,7% of the total. Considering the mean values for metrics, the results are: C = 0,98, S = 0,78, GI = 3,11 and CI = 0,81. The dose distribution was equivalent for treatment plans and reference plans. Quantitative analysis for IV/TV shows that these values are higher than 30% for treatment plans where shot density is large. Conclusion: This study demonstrates that de sphericity degree (φ) can be related to the dose distribution (IV/TV). Therefore the sphericity degree is a good parameter to evaluate the dose distribution of a plan for vestibular schwannoma treatment, considering the reference plan as being a spherical target using a leksell gamma knife® perfexion (LGKP). This study shows that the sphericity degree offers important information of the dose distribution outside and inside the target volume. This is not evaluated by the other parameters already implemented as metric to analyzing the GKP plans15

CONFIGURAÇÃO DO PROGRAMA INSTITUCIONAL DE BOLSA DE INICIAÇÃO À DOCÊNCIA (PIBID): EXPANSÃO E IMPACTOS NA UFPEL

O Programa Institucional de Bolsa de Iniciação à Docência (PIBID) é um Programa do Ministério da Educação, gerenciado pela CAPES (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior), cujo objetivo maior é o incentivo à formação de professores para atuarem na educação básica e a elevação da qualidade das escolas públicas. A Universidade Federal de Pelotas (UFPel) mesmo já tendo institucionalizado o PIBID desde 2010, no ano de 2014 expande significativamente suas ações, e novas áreas foram incorporadas ao trabalho na perspectiva de fomentar as ações de impacto social no universo da rede pública de educação. Esta pesquisa busca mapear as ações que estão sendo realizadas nos diferentes segmentos do Projeto Institucional do PIBID/UFPEL (2014-2017), e como estratégia metodológica utilizou-se a análise documental e o estudo de caso. Particularmente trazemos o caso do Curso de Educação Física da Escola Superior de Educação Física (ESEF) que atualmente conta com 68 bolsistas, onze supervisores que são professores de Educação Física da rede pública de ensino e quatro coordenadores de área, atuando em quatro escolas públicas municipais e estaduais. Os resultados preliminares apontam que com a expansão das ações na ESEF/UFPel, há uma aproximação dos bolsistas com o universo da escola tendendo a favorecer o processo de construção de suas identidades profissionais, bem como fortalecer suas aprendizagens

The proposition of an inexpensive chemically defined culture medium (MycoDef) for yeast studies

Chemically defined culture media (CDCMs) have their compositions qualitatively and quantitatively known. They are constituted of components able to meet the nutritional requirements of microorganisms. This study evaluated the employability of a multivitamin as the basis for the elaboration of a CDCM for experiments with yeasts. Candida albicans reference strains ATCC®90028™ and SC5314 were used. YNB® without amino acid (Difco Co.) was used as the standard in evaluations. For the preparation of the experimental culture medium (MycoDef), commercial multivitamin tablets had their coatings removed and were crushed until obtaining a fine powder; missing constituents were added. Comparisons were carried out evaluating aerobic and anaerobic planktonic growth rate, biofilm formation rate, whole-cell protein patterns by SDS-PAGE, minimum inhibitory concentrations and minimal fungicidal concentrations for clotrimazole, fluconazole, nystatin, and griseofulvin. Growth in MycoDef and YNB® did not differ between them (p>0.05) in both normoxic and anoxic conditions. Regarding employability for sensitivity testing, MycoDef showed performance like YNB®. The protein profiles of cells grown on both media did not differ in the number and positioning of bands. The results obtained allowed us to infer that MycoDef is a reliable low-cost culture medium useful for trials involving C. albicans

Assessment of ocular beta radiation dose distribution due to 106Ru/106Rh brachytherapy applicators using MCNPX Monte Carlo code

Purpose: Melanoma at the choroid region is the most common primary cancer that affects the eye in adult patients. Concave ophthalmic applicators with 106Ru/106Rh beta sources are the more used for treatment of these eye lesions, mainly lesions with small and medium dimensions. The available treatment planning system for 106Ru applicators is based on dose distributions on a homogeneous water sphere eye model, resulting in a lack of data in the literature of dose distributions in the eye radiosensitive structures, information that may be crucial to improve the treatment planning process, aiming the maintenance of visual acuity. Methods: The Monte Carlo code MCNPX was used to calculate the dose distribution in a complete mathematical model of the human eye containing a choroid melanoma; considering the eye actual dimensions and its various component structures, due to an ophthalmic brachytherapy treatment, using 106Ru/106Rh beta-ray sources. Two possibilities were analyzed; a simple water eye and a heterogeneous eye considering all its structures. Two concave applicators, CCA and CCB manufactured by BEBIG and a complete mathematical model of the human eye were modeled using the MCNPX code. Results and Conclusion: For both eye models, namely water model and heterogeneous model, mean dose values simulated for the same eye regions are, in general, very similar, excepting for regions very distant from the applicator, where mean dose values are very low, uncertainties are higher and relative differences may reach 20.4%. For the tumor base and the eye structures closest to the applicator, such as sclera, choroid and retina, the maximum difference observed was 4%, presenting the heterogeneous model higher mean dose values. For the other eye regions, the higher doses were obtained when the homogeneous water eye model is taken into consideration. Mean dose distributions determined for the homogeneous water eye model are similar to those obtained for the heterogeneous eye model, indicating that the homogeneous water eye model is a reasonable one. The determined isodose curves give a good visualization of dose distributions inside the eye structures, pointing out their most exposed volume....................................................Cite this article as:Barbosa NA, da Rosa LAR, de Menezes AF, Reis JP, Facure A, Braz D. Assessment of ocular beta radiation dose distribution due to 106Ru/106Rh brachytherapy applicators using MCNPX Monte Carlo code. Int J Cancer Ther Oncol 2014; 2(3):02038. DOI: 10.14319/ijcto.0203.

Losartan-induced acute interstitial nephritis

Nefrite intersticial aguda é uma causa comum de perda aguda de função renal. Exposição a drogas é o fator desencadeante mais freqüentemente relatado, porém auto-imunidade e infecções também estão associadas. Os inibidores da enzima de conversão da angiotensina têm sido relatados como possíveis agentes, porém não há relato na literatura de nefrite intersticial com uso de losartan. Descrevemos o caso de perda aguda de função renal após exposição a losartan, em paciente com dano renal prévio por nefropatia diabética, cuja biópsia renal diagnosticou nefrite intersticial aguda.Acute interstitial nephritis is an important cause of acute renal failure. The majority of cases results from exposure to drugs. However imune-mediated injury and infection are common causes. The angiotensin-converting enzyme inhibitors have been implicated as possible etiologic agents, but we could not find previous data of acute intestitial nephritis associated with losartan exposure. We report a case of acute renal failure after losartan exposure, in a patient with diabetic nephropathy. The final diagnosis was confirmed by renal biopsy: acute interstitial nephritis

Cartografia e diplomacia: usos geopolíticos da informação toponímica (1750-1850)

O artigo explora dimensões geopolíticas da toponímia, registradas em documentos cartográficos, desde as reformas empreendidas pelo consulado pombalino em meados do século XVIII, até às primeiras décadas do século XIX, em meio ao processo de afirmação do Estado imperial pós-colonial.This paper explores the geopolitical dimensions of toponymy as registered in cartographic documents dating from the reforms pushed through by the consulate of Marquis of Pombal in the mid 18th century to the early decades of the 19th century, as the post-colonial imperial State established itself

Alimentação popular em São Paulo (1920 a 1950): políticas públicas, discursos técnicos e práticas profissionais

This article discusses how the concept of lower-class eating habits came about and developed in the intellectual circles of São Paulo during the first half of the 20th century. It starts by reconstructing the elements of the debate around the income and ignorance of the underprivileged as the main reasons behind their bad eating habits. Then, it looks at the focal points for interventions and public policies proposed by the government to deal with the problem thus identified, namely: training methods to produce sanitation counselors capable of offering dietary guidance as well; popular educational campaigns and new learning sites in addition to schools (e.g. healthcare centers and households); lunch and other means of offering food at schools; and diagnostic studies about food intake and eating habits among laborers. Because they were translated into technical and scientific language, the proposals and policies implemented in São Paulo left traces in a variety of supporting documents and media (photographs, primers, posters, inquiry notebooks, and academic literature).O artigo discute a construção da idéia de alimentação popular nos meios intelectuais em São Paulo, na primeira metade do século XX. Para isso, reconstitui, como motivos da má alimentação, elementos do debate em torno da renda e da ignorância dos mais pobres. Identificado o problema, as propostas de intervenção e as políticas públicas concentraram-se em alguns setores, abordados neste trabalho: métodos para a formação de educadores sanitários aptos a atuar também na educação alimentar; campanhas de instrução popular e criação de novos lugares de aprendizado (além das escolas, os centros de saúde e os lares); merenda escolar e outras alternativas de alimentação nas escolas; e diagnósticos referentes ao conteúdo e à forma da alimentação dos operários. Traduzidas em discurso técnico-científicos, as propostas e políticas implementadas na cidade deixaram indícios em documentação de suporte e tipologia variados (fotografias, cartilhas, cartazes, cadernetas de inquéritos e textos acadêmicos).Universidade Federal de São Paulo (UNIFESP)UNIFESPSciEL

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio