Comparative study of micronucleus assays and dicentric plus ring chromosomes for dose assessment in particular cases of partial-body exposure.

Purpose: The goal was to compare the micronucleus (MN) and dicentric plus ring chromosomes (D + R) assays for dose assessment in cases of partial body irradiations (PBI). Materials and methods: We constructed calibration curves for each assay at doses ranging from 0 to 5 Gy of X-rays at dose rate of 0.275 Gy/min. To simulate partial-body exposures, blood samples from two donors were irradiated with 0.5, 1, 2 and 4 Gy and the ratios of irradiated to unirradiated blood were 25, 50, and 100%. Different tests were used to confirm if all samples were overdispersed or zero-inflated and for partial-body dose assessment we used the Qdr, Dolphin and Bayesian model. Results: In our samples for D + R calibration curve, practically all doses agreed with Poisson assumption, but MN exhibited overdispersed and zero-inflated cellular distributions. The exact Poisson tests and zero-inflated tests demonstrate that virtually all samples of D + R from PBI simulation fit the Poisson distribution and were not zero-inflated, but the MN samples were also overdispersed and zero-inflated. In the partial-body estimation, when Qdr and Dolphin methods were used the D + R results were better than MN, but the doses estimation defined by the Bayesian methodology were more accurate than the classical methods. Conclusions: Dicentric chromosomes continue to prove to be the best biological marker for dose assessment. However exposure scenarios of partial-body estimation, overdispersion and zero-inflation may not occur, it being a critical point not only for dose assessment, but also to confirm partial-body exposure. MN could be used as alternative assay for partial-body dose estimation, but in case of an accident without any information, the MN assay could not define whether the accident was a whole-body irradiation (WBI) or a PBI.

Labeling of adipose-derived stem cells with quantum dots provides stable and long-term fluorescent signal for ex vivo cell tracking.

Stem cells derived from adipose tissue (ADSC) have been used in cell therapy as an alternative to treat chronic and degenerative diseases. Using biomedical and image trials to track the cells when infused in the target tissue is essential to control cell migration and adhesion. The objective of the present study was to label and assess the adhesion of goat adipose tissue-derived stem cells (g-ADSC) after cell infusion in animal models by tracking luminescent intracytoplasmatic nanocrystals. The cells were labeled by using Qdots. The g-ADSCs infused with nanocrystal were prepared either fresh or fixed and further visualized under a fluorescence microscope. The labeled cells were infused in the goat mammary glands and mouse testicles and kidneys via tail vein injection. Thirty days after cell infusion, biopsy was carried out for analyses. The g-ADSC cultures were presented with high cellularity and fibroblast morphology, even after infusion of the nanocrystals. It was possible, by processing in paraffin and under fluorescence microscopy, demonstrating the success of the labeling in the long term. Freezing mammary gland biopsies in liquid NO2 did not alter the quality of labeling with Qdots. Therefore, g-ADSCs can be labeled with intracytoplasmatic nanocrystals (Qdots) enabling their in vitro and ex vivo tracking.

Role of the autologous mesenchymal stem cells compared with platelet rich plasma on cicatrization of cutaneous wounds in diabetic mice / Papel das células-tronco mesenquimais autólogas em comparação com plasma rico em plaquetas na cicatrização de feridas cutâneas em camundongos diabéticos

Chronic cutaneous lesions affect 15% of diabetic human patients and represent a risk 15 to 46 times larger of limb amputations compared to people with normal glycemia. It is assumed that half of these amputations could be prevented by early treatment of wounds, for example, with proper cell therapy. Objectives: In this study, the action of the autologous transplant of mesenchymal stem-cells (MSC) was evaluated compared to the treatment with autologous platelet rich plasma (PRP) in the cicatrization of cutaneous lesions induced in diabetic mice. These animals were previously treated with streptozootocin to induce diabetes mellitus and round wounds of 1.5cm in diameter were created in the posterior region. Diameters of the wounds and healing time were evaluated during 30 days and the results were submitted to variance analysis and Tukey's test average. It was noticed that the animals treated with MSC presented a more accelerated cicatrization of the cutaneous lesion than the animals treated with PRP. However, the treatment with PRP presented better results than just the daily asepsis of the lesions with saline or covering them with semi-permeable bandage. Besides, the use of semi-permeable bandage kept the cutaneous lesions of diabetic mice did not interfere negatively with cicatrization, proved to be harmless to use, but kept the cutaneous lesions more hydrated than the ones exposed to the environment.(AU)

Lesões cutâneas crônicas afetam 15% dos pacientes diabéticos e humanos representam um risco 15 a 46 vezes maior de amputações de membros em comparação com as pessoas com a glicemia normal. Supõe-se que a metade destas amputações poderia ser evitada por meio do tratamento precoce das feridas cutâneas com, por exemplo, uma adequada terapia celular. Objetivos: Neste estudo, a ação do transplante autólogo de células estaminais mesenquimais (MSC) foi avaliada em comparação com o tratamento com plasma rico em plaquetas autólogo (PRP) na cicatrização de lesões cutâneas induzidas em camundongos diabéticos. Estes animais foram previamente tratados com estreptozotocina para induzir diabetes mellitus e feridas redondas de 1,5 cm de diâmetro foram criadas na região posterior. Os diâmetros dos ferimentos e tempo de cicatrização foram avaliados durante 30 dias e os resultados foram submetidos à análise de variância e média pelo teste de Tukey. Verificou-se que os animais tratados com MSC apresentam uma cicatrização mais acelerada da lesão cutânea que do que os animais tratados com PRP. No entanto, o tratamento com PRP apresentou melhores resultados do que apenas a assepsia das lesões diariamente com solução salina ou cobrindo-os com atadura semi-permeável. Além disso, a utilização de atadura semi-permeável mantidas as lesões cutâneas de camundongos diabéticos não interfere negativamente com a cicatrização, provou ser inofensiva para usar, mas manteve as lesões cutâneas hidratadas mais do que os expostos ao meio ambiente.(AU)

Celiotomy by plastrotomy in a yellow-footed tortoise (geochelone denticulata)

One herein reports a successful case of celiotomy by plastrotomy for removal of foreign bodies in yellow-footed tortoise (Geochelone denticulata). The animal was treated at the Veterinary Hospital of the Federal University of Piaui, with appetite loss, regurgitation, constipation, lethargy, reluctance to walk and slightly reddish ocular mucous membranes. Radiographic examination was performed, confirming the presence of foreign bodies in the stomach. The tortoise underwent celiotomy by plastrotomy for the removal of the foreign bodies. The opening of the plastron was performed through the abdominal shields, with the aid of a circular mini grinding saw. One performed an incision in the midline between the two abdominal veins to access the abdominal cavity. A gastrotomy for removal of the foreign bodies (nails, toothpicks, stones, pieces of plastic, glass and crockery pieces) was performed after the location of the stomach. The surgery was successful and confirmed with radiographic evaluation in the immediate postoperative period. The celiotomy by plastrotomy for removal of foreign bodies in that animal proved to be a viable, very important and safe technique to the survival of chelonians.

Neste relato descreve-se um caso bem sucedido de celiotomia por plastrotomia para remoção de corpos estranhos em uma jabuti-tinga (Geochelone denticulata). O animal foi atendido no Hospital Veterinário da Universidade Federal do Piauí apresentando falta de apetite, regurgitação, constipação, letargia, relutância em andar e mucosas oculares hiperêmicas. Foi realizado exame radiográfico, o qual confirmou presença de corpos estranhos no estômago. O animal foi submetido à celiotomia por plastrotomia para remoção dos corpos estranhos. A abertura do plastrão foi realizada através dos escudos abdominais, com o auxílio de uma mini-serra circular de retífica. Foi feita uma incisão na linha média entre as duas veias abdominais para se acessar a cavidade abdominal e, uma vez exposto, o estômago foi incisado para remoção dos corpos estranhos (grampos, palitos de dente, pedras, peças de plástico, fragmentos de louças e vidros). A cirurgia foi bem sucedida e a remoção total dos corpos estranhos foi confirmada por radiografia realizada no pós-operatório imediato. A celiotomia por plastrotomia para remoção de corpos estranhos neste animal demonstrou ser uma técnica muito importante, segura e viável para a sobrevivência de quelônios.