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Herein, we aimed to evaluate cultures of femoral chondrocytes from offspring of rats with intrauterine growth restriction (IUGR) induced by maternal hyperthyroidism. Fourteen adult female Wistar rats were divided into two groups, a control group and a group treated with daily L-thyroxine administration using an orogastric tube (50 µg/animal/day) during pregnancy. Three days after birth, the offspring were euthanized for chondrocyte extraction. At 7, 14, and 21 days, viability and alkaline-phosphatase (ALP) activity were assessed using the MTT assay and BCIP/NBT method, respectively, in a 2D culture. Pellets (3D cultures) were stained with periodic acid Schiff (PAS) to assess the morphology and percentage of PAS+ areas. The gene transcripts for Col2, Col10, Acan, Sox9, and Runx2 were evaluated by qRT-PCR. The MTT and ALP-assay results showed no significant differences between the groups. Maternal hyperthyroidism did not alter the chondrocyte morphology, but significantly reduced the percentage of PAS+ areas, decreased the expression of the gene transcripts of Col2 and Acan, and increased Sox9 expression. Maternal hyperthyroidism in rats alters the composition and gene expression of the matrix produced by chondrocytes from offspring with IUGR. This may be one of the mechanisms through which excess maternal thyroid hormones reduce offspring bone growth.

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The use of stem cells in cell therapies has shown promising results in the treatment of several diseases, including diabetes mellitus, in both humans and animals. Mesenchymal stem cells (MSCs) can be isolated from various locations, including bone marrow, adipose tissues, synovia, muscles, dental pulp, umbilical cords, and the placenta. In vitro, by manipulating the composition of the culture medium or transfection, MSCs can differentiate into several cell lineages, including insulin-producing cells (IPCs). Unlike osteogenic, chondrogenic, and adipogenic differentiation, for which the culture medium and time are similar between studies, studies involving the induction of MSC differentiation in IPCs differ greatly. This divergence is usually evident in relation to the differentiation technique used, the composition of the culture medium, the cultivation time, which can vary from a few hours to several months, and the number of steps to complete differentiation. However, although there is no "gold standard" differentiation medium composition, most prominent studies mention the use of nicotinamide, exedin-4, ß-mercaptoethanol, fibroblast growth factor b (FGFb), and glucose in the culture medium to promote the differentiation of MSCs into IPCs. Therefore, the purpose of this review is to investigate the stages of MSC differentiation into IPCs both in vivo and in vitro, as well as address differentiation techniques and molecular actions and mechanisms by which some substances, such as nicotinamide, exedin-4, ß-mercaptoethanol, FGFb, and glucose, participate in the differentiation process.

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This article describes the synthesis, characterization and in vivo cytotoxic evaluation of thiol-functionalized superparamagnetic iron oxide magnetic nanoparticles (SPIONs). They have been employed as potential vehicles for a large number of biomedical applications, such as drug delivery. Fe3O4 nanoparticles were synthesized by coprecipitation of iron salts and coated with L-cysteine. The physicochemical, morphological, and magnetic properties of Cys-Fe3O4 nanoparticles were characterized by different experimental techniques. To evaluate their applicability in nanomedicine we evaluated their cytotoxicity using Balb/C mice. The results show that Cys-SPIONs are good candidates as nanocarriers in biomedical applications.

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A capivara (Hydrochoerus hydrochoeris), um roedor silvestre típico no continente Sul-americano, é utilizada como fonte de alimento em toda a sua região de ocorrência, sendo um importante componente na dieta de povo indígena e população rural do Brasil. O conhecimento da morfologia fornece bases para outras áreas de atuação, bem coamo, para o manejo biológico de animais silvestres. Devido à escassez na literatura de estudos anatômicos e morfológicos do aparelho respiratório da capivara, o objetivo deste trabalho é analisar os órgãos deste aparelho, macro e microscopicamente, para que possamos adquirir melhor conhecimento básico e compará-lo com o de animais da mesma subordem (Histricomorfos) e com outras espécies de mamíferos. Vimos que o aparelho respiratório da capivara é formado pelas narinas, fossas nasais, cavidade nasal, seios paranasais, faringe, laringe, traqueia e pulmões. O nariz se localiza em plano nasal com as narinas dispostas lateralmente. A maior parte da cavidade nasal está ocupada pelas conchas nasais, que se apresentam como estruturas em formato de espiral, com seus respectivos meatos. A laringe está delimitada por suas cartilagens e está em comunicação com a traqueia. A traqueia é um tubo cartilaginoso flexível e membranoso, com anéis incompletos em formato de "C", que se bifurca em sua parte terminal, formando a carina traqueal. Os pulmões apresentam-se em pares, direito (com quatro lobos) e esquerdo (com dois lobos), localizados na cavidade torácica. As árvores brônquicas são formadas pelo brônquio primário e por uma sequência intrapulmonar que inclui brônquios intrapulmonares, bronquíolos, bronquíolos terminais e bronquíolos respiratórios.(AU)

The capybara, a wild rodent typical of the South American continent, is a source of food in all regions of its occurrence and is an important component in the diet of indigenous people and the rural population of Brazil. Knowledge of morphology is basic for the biological management of wild animals. Due to the scarcity of literature on morphological and anatomical studies of the respiratory tract of capybara, the aim of this study is to analyze the organs of this apparatus, macro and microscopically, so we can acquire better basic knowledge and compare it with that of animals of the same suborder (Histricomorpha) and with other species of mammals. We have seen that the respiratory tract of capybara is formed through the nostrils, nasal, nasal cavity, paranasal sinuses, phisarynx, larynx, trachea and lungs. The nose is located in nasal plan with nostrils arranged laterally. The largest part of the nasal cavity of the capybara is occupied by the turbinates, which performe as spiral-shaped structures, with their respective meati. The larynx is bounded by cartilage and in communication with the trachea. The trachea is a flexible cartilaginous and membranous tube, with incomplete rings in the shape of a "C", which is bifurcated in its terminal part, forming the tracheal carina. The lungs of capybaras are in pairs, right (with four lobes) and left (with two lobes), located in the chest cavity. The bronchial tree of capybara is formed by primary bronchi and by a sequence that includes intrapulmonary bronchi, bronchioles, terminal bronchioles, and respiratory bronchioles.(AU)

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A Distrofia Muscular de Duchenne (DMD) é uma doença genética de caráter recessivo que caracterizada por fraqueza muscular progressiva de cintura pélvica e escapular evoluindo para insuficiência respiratória e, ou cardíaca. O camundongo mdx é um modelo amplamente utilizado para estudos da DMD. Apesar do fenótipo destes animais serem mais suave, estes apresentam o principal músculo respiratório, o diafragma com morfologia e bioquímica semelhante à DMD humana, fato este que pode comprometer a função respiratória e consequentemente os pulmões. Foi realizado um estudo anatômico descritivo do parênquima pulmonar dos pulmões de 5 animais modelo mdx comparando estes com os pulmões de 5 camundongos BALB/C57 (Mus musculus). Os pulmões foram analisados macroscopicamente e através de microscopia de luz e eletrônica de varredura. Os achados sugerem que o modelo mdx apresenta morfologia pulmonar semelhante aos camundongos BALB/C57 e que seu uso deve ser cauteloso e criterioso em ensaios clínicos que aborde este órgão.(AU)

The Duchenne Muscular Dystrophy (DMD) is a recessive genetic disease characterized by progressive muscle weakness of the pelvic and scapular girdle and progressing to respiratory or heart failure. The mdx mouse is a model widely used for studies. Although they possess a milder phenotype, the morphology and biochemistry of the diaphragm are similar to human DMD. We performed a descriptive anatomical study of the pulmonary parenchyma of five mdx animal models and compared these with the lungs of 5 mice BALB/C57 (Mus musculus). The findings suggest that the mdx model has morphological features similar to BALB/C57 mice and it must be used with caution in clinical trials which involve the lung.(AU)

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The Galea spixii inhabits semiarid vegetation of Caatinga in the Brazilian Northeast. They are bred in captivity for the development of researches on the biology of reproduction. Therefore, the aim of this study is characterize the estrous cycle of G. spixii, in order to provide information to a better knowledge of captive breeding of the species. The estrous cycle was monitored by vaginal exfoliative cytology in 12 adult females. After the detection of two complete cycles in each animal, the same were euthanized. Then, histological study of the vaginal epithelium, with three females in each phase of the estrous cycle was performed; five were paired with males for performing the control group for estrous cycle phases, and three other were used to monitor the formation and rupture of vaginal closure membrane. By vaginal exfoliative cytology, predominance of superficial cells in estrus, large intermediate cells in proestrus, intermediate and parabasal cells, with neutrophils, in diestrus and metestrus respectively was found. Estrus was detected by the presence of spermatozoa in the control group. By histology, greater proliferation of the vaginal epithelium in proestrus was observed. We conclude that the estrous cycle of G. spixii lasts 15.8 ± 1.4 days and that the vaginal closure membrane develops until complete occlusion of the vaginal ostium, breaking after few days. Future studies may reveal the importance of this fact for the reproductive success of this animal...

Os Galea spixii habitam a vegetação semiárida da Caatinga, no Nordeste brasileiro. Eles são criados em cativeiro para realização de pesquisas relacionadas a biologia da reprodução. Sendo assim, o objetivo deste trabalho foi caracterizar o ciclo estral de G. spixii para obtenção de informações que melhorem o conhecimento do manejo reprodutivo da espécie em cativeiro. O ciclo estral foi monitorado por citologia esfoliativa vaginal em doze fêmeas adultas. Após a detecção de dois ciclos completos em cada animal, os mesmos foram eutanasiados. Em seguida foi realizado estudo histológico do epitélio vaginal com três fêmeas em cada fase do ciclo estral; cinco foram pareadas com machos para realização do grupo controle e outras três fêmeas foram utilizadas para monitorar a formação e ruptura da membrana de oclusão vaginal. Através de citologia esfoliativa vaginal, constatou-se predomínio de células superficiais em estro, células intermediárias grandes em proestro, células intermediárias pequenas e células parabasais com presença de neutrófilos em diestro e metaestro, respectivamente. O estro foi detectado pela presença de espermatozoides no grupo controle. Através de histologia, observou-se uma maior proliferação no epitélio vaginal no proestro. Concluiu-se que o ciclo estral de G. spixii dura em média 15.8 ± 1.4 dias e a membrana de oclusão vaginal se desenvolve até completa oclusão do óstio vaginal externo, rompendo-se em poucos dias. Futuros estudos podem revelar a importância deste último fato para o sucesso reprodutivo deste animal...

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