13 research outputs found
The Barretos Cancer Hospital Animal Facility: implementation and results of a dedicated platform for preclinical oncology models
The Barretos Cancer Hospital Animal Facility (BCHAF) is a unique facility in Brazil exclusively dedicated to working with animal models for cancer research. In this article, we briefly present our modern facility and the main experiments performed, focusing on mutant strains of mice (PTCH-knockout and ApcMin mice), xenograft models, and patient-derived xenografts (PDXs). Our results show the progress and challenges in establishing these models and the need for having an appropriate representation of our cancer population to better understand tumor biology and to identify cancer biomarkers, which could be putatively targeted, allowing for personalized therapy.This study was funded by the Public Ministry of Labor Campinas (Research, Prevention and Education of Occupational Cancer) and by Pio XII Foundation, Barretos Cancer Hospital internal funds, Grant Number: 13/2021
Structure and dynamics of the community of periphytic algae in a subtropical reservoir (state of São Paulo, Brazil)
Chemical composition and taxonomic structure vertical and seasonal variation of periphyton community in a shallow hypereutrophic reservoir
Variação vertical e sazonal da composição química e estrutura da comunidade perifítica em reservatório raso hipereutrófico (Lago das Garças, São Paulo, Brasil) Borduqui, M., Ferragut, C. and Bicudo, CEM. Instituto de Botânica, Seção de Ecologia, CP 3005, CEP 01061-970, São Paulo, SP, Brasil e-mail: [email protected], [email protected], [email protected] Abstract: Vertical and seasonal evaluation of the chemical composition, biomass and taxonomic classes of the periphyton community were studied in a shallow hypereutrophic reservoir. Water physical and chemical characteristics, as well as biological features of periphyton were studied at 5 depths (subsurface, 1 m, 2 m, 3 m and bottom) during the dry (July) and rainy (January) periods. Periphyton growing on glass microscope slides placed at different depths was sampled after 28 days colonization. Periphyton attributes studied were chlorophyll-a, dry mass, ash free dry mass, chemical composition and algal taxonomic classes. Compared to the rainy period, the dry one was characterized by lower resistance to mixing, homogeneous P-PO 4 and N-NH 4 concentration vertical profile, greater optical depth and smaller total phytoplankton biomass. Periphyton showed the smallest biomass and algal growth, and absolute dominance of Cyanobacteria during the rainy period, when the Cyanobacteria bloom was most intense. Unlike the dry period, the smallest bloom intensity allowed the greatest light penetration, favoring the increase of photosynthetic biomass, the growth of algae and the dominance of Bacillariophyceae at the surface and Cyanobacteria at all other depths. Periphyton chemical composition reflected the environment's nutritional conditions, evidencing the periphyton ability for nutrient retention, independent of the algal biomass amount, and that such a condition is more evident mainly concerning the P contents. Molar N:P ratio indicated that the periphyton community was P-limited at all depths and climatic periods studied. Finally, biomass and periphyton community algal taxonomic classes' structure varied both in seasonal and vertical scale, the Cyanobacteria bloom intensity being the controlling factor towards the periphyton biomass increase, whereas the nutrient status and the P contents of periphyton were conditioned to the nutrients' availability in the water column. Keywords: chemical composition, Cyanobacteria bloom, periphyton, structure, hipereutrophic reservoir. Resumo: Avaliação em escala vertical e sazonal da composição química, biomassa e estrutura de classes da comunidade perifítica em reservatório hipereutrófico raso. Foram analisadas variáveis físicas, químicas e biológicas da água em cinco profundidades (subsuperfície, 1 m, 2 m, 3 m e fundo) nos períodos seco (julho) e chuvoso (janeiro). O perifíton desenvolvido em lâminas de vidro distribuídas em cada profundidade foi amostrado após 28 dias de colonização. Os atributos do perifíton analisados foram: clorofila-a, massa seca, massa seca livre de cinzas, composição química e classes taxonômicas das algas. Em relação ao chuvoso, o período seco caracterizou-se por menor resistência à mistura, perfil vertical homogêneo das concentrações de P-PO 4 e N-NH 4 , maior profundidade óptica e menor biomassa do fitoplâncton. O perifíton apresentou a menor biomassa, menor crescimento algal e dominância absoluta de Cyanobacteria no período chuvoso, quando a floração de Cyanobacteria foi mais intensa. Diferente no período seco, a menor intensidade da floração permitiu a maior penetração de luz, favorecendo o aumento de biomassa e do crescimento algal e a dominância de Bacillariophyceae na superfície e de Cyanobacteria nos demais estratos. A composição química do perifíton refletiu as condições nutricionais do meio, evidenciando a capacidade de retenção de nutrientes do perifíton, independente da quantidade de biomassa algal, principalmente em relação ao conteúdo de P. A razão molar N:P indicou uma comunidade perifítica P-limitada em todas as profundidades e períodos climáticos. Finalmente, a biomassa e a estrutura de classes taxonômicas da comunidade perifítica variaram em escala sazonal e vertical, sendo a intensidade da floração de Cyanobacteria o fator controlador do incremento da biomassa perifítica, enquanto que o 'status' dos nutrientes e o conteúdo de P foram associados à disponibilidade de nutrientes na coluna d'água. Palavras-chave: composição química, estrutura, floração de Cyanobacteria, perifíton, reservatório hipereutrófico. Biological Limnology 382 Borduqui, M., Ferragut, C. and Bicudo, CEM
Whole-Brain Voxel-Based Morphometry in Kallmann Syndrome Associated with Mirror Movements
Whole-Brain Voxel-Based Morphometry in Kallmann Syndrome Associated with Mirror Movements
BACKGROUND AND PURPOSE: There are 2 main hypotheses concerning the cause of mirror movements (MM) in Kallmann syndrome (KS): abnormal development of the primary motor system, involving the ipsilateral corticospinal tract, and lack of contralateral motor cortex inhibitory mechanisms, mainly through the corpus callosum. The purpose of our study was to determine white and gray matter volume changes in a KS population by using optimized voxel-based morphometry (VBM) and to investigate the relationship between the abnormalities and the presence of MM, addressing the 2 mentioned hypotheses. MATERIALS AND METHODS: T1-weighted volumetric images from 21 patients with KS and 16 matched control subjects were analyzed with optimized VBM. Images were segmented and spatially normalized, and these deformation parameters were then applied to the original images before the second segmentation. Patients were divided into groups with and without MM, and a t test statistic was then applied on a voxel-by-voxel basis between the groups and controls to evaluate significant differences. RESULTS: When considering our hypothesis a priori, we found that 2 areas of increased gray matter volume, in the left primary motor and sensorimotor cortex, were demonstrated only in patients with MM, when compared with healthy controls. Regarding white matter alterations, no areas of altered volume involving the corpus callosum or the projection of the corticospinal tract were demonstrated. CONCLUSION: The VBM study did not show significant white matter changes in patients with KS but showed gray matter alterations in keeping with a hypertrophic response to a deficient pyramidal decussation in patients with MM. In addition, gray matter alterations were observed in patients without MM, which can represent more complex mechanisms determining the presence or absence of this symptom