In vitro irradiation system for radiobiological experiments

Background: Although two-dimensional (2-D) monolayer cell cultures provide important information on basic tumor biology and radiobiology, they are not representative of the complexity of three-dimensional (3-D) solid tumors. In particular, new models reproducing clinical conditions as closely as possible are needed for radiobiological studies to provide information that can be translated from bench to bedside. Methods: We developed a novel system for the irradiation, under sterile conditions, of 3-D tumor spheroids, the in vitro model considered as a bridge between the complex architectural organization of in vivo tumors and the very simple one of in vitro monolayer cell cultures. The system exploits the same equipment as that used for patient treatments, without the need for dedicated and highly expensive instruments. To mimic the passage of radiation beams through human tissues before they reach the target tumor mass, 96-multiwell plates containing the multicellular tumor spheroids (MCTS) are inserted into a custom-built phantom made of plexiglass, the material most similar to water, the main component of human tissue. Results: The system was used to irradiate CAEP- and A549-derived MCTS, pre-treated or not with 20 \u3bcM cisplatin, with a dose of 20 Gy delivered in one session. We also tested the same treatment schemes on monolayer CAEP and A549 cells. Our preliminary results indicated a significant increment in radiotoxicity 20 days after the end of irradiation in the CAEP spheroids pre-treated with cisplatin compared to those treated with cisplatin or irradiation alone. Conversely, the effect of the radio- chemotherapy combination in A549-derived MCTS was similar to that induced by cisplatin or irradiation alone. Finally, the 20 Gy dose did not affect cell survival in monolayer CAEP and A549 cells, whereas cisplatin or cisplatin plus radiation caused 100% cell death, regardless of the type of cell line used. Conclusions: We set up a system for the irradiation, under sterile conditions, of tumor cells grown in 3-D which allows for the use of the same dose intensities and schedules utilized in clinical practice. This irradiation system, coupled with 3-D cell cultures, has the potential to generate information that could be used to individually tailor radiotherap

Ocorrência de tatu-de-rabo-mole, Cabassous unicinctus (Cingulata, Dasypodidae) no Pantanal, Brasil.

Há poucos registros na literatura científica sobre a ocorrência de tatu-de-rabo-mole (Cabassous unicinctus) na planície do Pantanal e nos planaltos adjacentes. Entretanto, dados relativamente recentes com base em espécimes coletados, registros fotográficos e observações de campo revelam que a espécie tem ampla distribuição na porção sul da planície, em regiões como Pantanal da Nhecolândia e Paiaguás, bem como no entorno do Pantanal (Diamantino, Taboco, Coxim, Terenos, Aquidauna, Bodoquena e Rochedo). A espécie apresenta ampla plasticidade ecológica em relação ao uso de habitat, sendo registrada tanto em campos com pastagens cultivadas (Brachiaria spp.), quanto campos inundáveis, capões, cerradão e cerrado. Com base em comparação dos exemplares fotografados no Pantanal e áreas do entorno com dados literários, verificou-se que os mesmos pertencem à subespécie Cabassous unicinctus squamicaudis.bitstream/CPAP-2010/57165/1/BP87.pd

Topology optimization for human proximal femur considering bi-modulus behavior of cortical bones

© Springer International Publishing Switzerland 2015. The material in the human proximal femur is considered as bi-modulus material and the density distribution is predicted by topology optimization method. To reduce the computational cost, the bi-modulus material is replaced with two isotropic materials in simulation. The selection of local material modulus is determined by the previous local stress state. Compared with density prediction results by traditional isotropic material in proximal femur, the bi-modulus material layouts are different obviously. The results also demonstrate that the bi-modulus material model is better than the isotropic material model in simulation of density prediction in femur bone

Amelanotic/hypomelanotic lentigo maligna: Dermoscopic and confocal features predicting diagnosis

Background: Amelanotic/hypomelanotic lentigo maligna and lentigo maligna melanoma (AHLM/LMM) may be very difficult to diagnose at an early stage. Objectives: To quantify the predictive value of dermoscopic and reflectance confocal microscopy (RCM) features for AHLM/LMM. Methods: Dermoscopic and RCM images of histopathologically diagnosed AHLM/LMM, amelanotic/hypomelanotic benign lesions (AHBL), and amelanotic/hypomelanotic basal and squamous cell carcinomas (AHBCC/AHSCC) of the head and neck from consecutive patients were retrospectively collected and blindly evaluated by three observers to assess presence or absence of dermoscopic and RCM criteria. Results: Overall, 224 lesions in 216 patients including LM/LMM (n = 55, 24.6%), AHBL (n = 107, 47.8%) and AHBCC/AHSCC (n = 62, 27.7%) were analysed. Multivariable analysis showed that milky-red areas (OR = 5.46; 95% CI: 1.51–19.75), peripheral light brown structureless areas (OR = 19.10; 4.45–81.96), linear irregular vessels (OR = 5.44; 1.45–20.40), and asymmetric pigmented follicles (OR = 14.45; 2.77–75.44) at dermoscopy, and ≥3 atypical cells in five fields (OR = 10.12; 3.00–34.12) and focal follicular localization of atypical cells at dermo-epidermal junction (DEJ) (OR = 10.48; 1.10–99.81) at RCM were significantly independent diagnostic factors for AHLM/LMM vs. AHBL. In comparison with AHBCC/AHSCC, peripheral light brown structureless area (OR = 7.11; 1.53–32.96), pseudonetwork around hair follicles (OR = 16.69; 2.73–102.07), and annular granular structures (OR = 42.36; 3.51–511.16) at dermoscopy and large dendritic (OR = 6.86; 3.15–38.28) and round pagetoid cells (OR = 26.78; 3.15–227.98) at RCM led to a significantly increased risk of diagnosing AHLM/LMM. Conclusions: Amelanotic/hypomelanotic lentigo maligna and lentigo maligna melanoma may have the same dermoscopic features of AHM on other body sites, such as milky red areas, peripheral light brown structureless areas and linear irregular vessels. These features, asymmetric pigmented follicles and at RCM ≥ 3 atypical cells in five fields and focal follicular extension of atypical cells at DEJ may help in recognizing AHLM/LMM even when LM conventional features (e.g., obliteration of hair follicles under dermoscopy and large pagetoid cells under RCM) are absent or present only in very small areas of the lesion

Molecular, anatomical and physiological properties of a genetically modified soybean line transformed with rd29A:AtDREB1A for the improvement of drought tolerance.

We evaluated the molecular, anatomical and physiological properties of a soybean line transformed to improve drought tolerance with an rd29A:AtDREB1A construct. This construct expressed dehydration- responsive element binding protein DREB1A from the stress-inducible rd29A promoter. The greenhouse growth test included four randomized blocks of soybean plants, with each treatment performed in triplicate. Seeds from the non-transformed soybean cultivar BR16 and from the genetically modified soybean P58 line (T2 generation) were grown at 15% gravimetric humidity for 31 days. To induce water deficit, the humidity was reduced to 5% gravimetric humidity (moderate stress) for 29 days and then to 2.5% gravimetric humidity (severe stress). AtDREB1A gene expression was higher in the genetically modified P58 plants during water deficit, demonstrating transgene stability in T2 generations and induction of the rd29A promoter. Drought-response genes, including GmPI-PLC, GmSTP, GmGRP, and GmLEA14, were highly expressed in plants submitted to severe stress. Genetically modified plants had higher stomatal conductance and consequently higher photosynthetic and transpiration rates. In addition, they had more chlorophyll. Overexpression of AtDREB1A may contribute to a decrease in leaf thickness; however, a thicker abaxial epidermis was observed. Overexpression of AtDREB1A in soybean appears to enhance drought tolerance

Tumour microvessel density as predictor of chemotherapy response in breast cancer patients

The aim of this study was to evaluate the predictive value of intratumoural microvessel density in breast cancer. We studied immunohistochemically primary tumours of 104 patients with metastasised breast cancer who took part in a randomised multicentre trial comparing docetaxel to sequential methotrexate and 5-fluorouracil. Vessels were highlighted with factor VIII staining and counted microscopically. Microvessel density was compared with clinical response to chemotherapy and patient survival. The microvessel density of the primary tumour was not significantly associated with patient's response to chemotherapy, time to progression or overall survival in the whole patient population or in the docetaxel or methotrexate and 5-fluorouracil groups. However, disease-free survival was longer in patients with low microvessel density (P=0.01). These findings suggest that microvessel density of the primary tumour cannot be used as a predictive marker for chemotherapy response in advanced breast cancer