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Graphene oxide nanoribbons (O-GNR) surges as an interesting nanomaterial for biomedical applications due to feasibility to incorporate functional groups and possible bactericidal properties. Herein, high concentrations of O-GNR were biologically evaluated using human osteoblast cells and gram positive and negative bacteria. Briefly, our goal were to evaluate: (1) synthetic pathway, (2) characterization and (3) effects of O-GNR composition and structural factors as a new approach for biomedical applications. For this, O-GNR were produced combining chemical vapor deposition and oxygen plasma treatment of multiwalled carbon nanotubes. Then, we analyzed the bioactivity, cell viability, osteogenic differentiation, matrix mineralization, mRNA levels of the five genes related direct to bone repair and bactericidal effect of high concentrations of O-GNR (10µgmL-1, 100µgmL-1, 200µgmL-1 and 300µgmL-1). Impressively, O-GNR showed no cytotoxic effects up to a concentration of 100µgmL-1 and no gene expression alteration when used in its dose. We also observed that S. aureus and E. coli bacteria are susceptible to damage when incubated with 100µgmL-1 of O-GNR, showing approximately 50% of bacterial death. We consider that O-GNR displays attractive properties when used at a suitable dose, displaying bactericidal effect and apparently lacking to cause damages in the bone repair process.

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Researchers have been looking for modifying surfaces of polymeric biomaterials approved by FDA to obtain nanofeatures and bactericidal properties. If modified, it would be very interesting because the antibiotic administration could be reduced and, therefore, the bacterial resistance. Here, we report the electrospinning of poly (lactic acid) (PLA) with high loadings of titanium dioxide nanoparticles (TiO2, 1-5wt%) and their bactericidal properties. TiO2 nanoparticles have been recognized for a long time for their antibacterial, low cost and self-cleaning properties. However, their ability to reduce bacteria functions when used in polymers has not been well studied to date. In this context, we aimed here to generate nanostructured PLA electrospun fiber-TiO2 nanoparticle composites for further evaluation of their bactericidal activity and cell viability. TEM and SEM micrographs revealed the successful electrospinning of PLA/TiO2 and the generation of polymer-TiO2 nanostructures. When increasing the TiO2 concentration, we observed a proportional increase in the nanoparticle density along the fiber and surface. The nanostructured PLA/TiO2 nanofibers showed no mammalian cell toxicity and, most importantly, possessed bactericidal activity with higher TiO2 loads. Such results suggest that the present PLA electrospun fiber-TiO2 nanoparticle composites should be further studied for a wide range of biomedical applications.

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Forest destruction has progressively hampered the survival of many species, and this is why it is so important to study of the lives of primates in captivity. This study aimed to describe the morphological aspects of the female reproductive tract of Sapajus apella. We used five animals obtained from the National Primate Center, Ananindeua - PA. The ovaries were paired, compact and symmetrical and had a smooth surface. The uterine tubes were bilateral and convoluted in adult animals and straight in young individuals. The uterus was simple and located in the pelvic region. The vagina was a long structure due to the position of the uterus. The external genitalia were located in the urogenital perineum and consisted of dark pigmented labia majora and labia minora, a vaginal vestibule as long as the vagina and a well-developed clitoris. The results showed that the genitals of S. apella resemble those of other Neotropical primates.

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The Bradypus variegatus inhabits the forests of South America and feeds from leaves, branches and sprouts from different plants. Due to its diet and the lack of literature on the morphological aspect of Xenarthras, five Bradypus variegatus tongues from animals which died from natural causes were evaluated, and they came from Pará State Museum Emílio Goeldi and were donated to the Laboratory of Animal Morphological Research (LaPMA) from UFRA, for revealing the different types of papillae and epithelial-connective tissue. Macroscopically, the tongues presented elongated shape, rounded apex, body, root, median sulcus in the root's apex, and two vallate papillae. The mucous membrane of the tongue revealed a keratinized stratified pavement epithelium, while the ventral surface of the tongue was thin and smooth, not provided with any type of papillae. However, the dorsal surface of the tongue was irregular with the presence of three types of papillae: filiform, fungiform and vallate papillae. The filiform papillae found were of a simple type, presenting a rounded base, irregularly distributed with a larger concentration and development on the tongue's apex and body. The fungiform papilla showed a practically smooth surface with irregular format, with the presence of gustatory pores; these were found all over the dorsal surface, with larger concentration at the rostral part of the apex. Only two vallate papillae were observed disposed in the root of the tongue, surrounded by a deep groove, and revealing several taste buds. The tongues from Bradypus variegatus presented gustatory papillae similar to the ones described for other Xenarthras species and wild mammals...

A Bradypus variegatus habita florestas da América do Sul e alimenta-se de folhas, ramos e brotos de várias plantas. Em decorrência de sua dieta, bem como da escassez de literatura sobre aspectos morfológicos dos Xenarthras, avaliaram-se cinco línguas de Bradypus variegatus, que foram a óbito por causas naturais, provenientes do Museu Paraense Emílio Goeldi e doados ao Laboratório de Pesquisa Morfológica Animal (LaPMA) da UFRA, a fim de se elucidarem os diferentes tipos de papilas e a interface epitélio-tecido conjuntivo. Macroscopicamente, as línguas apresentaram formato alongado, ápice arredondado, corpo, raiz, sulco mediano do ápice à raiz e duas papilas valadas. A mucosa da língua revelou epitélio de revestimento pavimentoso estratificado queratinizado, enquanto a face ventral era delgada e lisa, desprovida de qualquer tipo de papila. Já a face dorsal apresentou-se irregular, com a presença de três tipos papilares: papilas filiformes, fungiformes e valadas. As papilas filiformes encontradas eram do tipo simples, com base circular, distribuídas irregularmente, com maior concentração e desenvolvimento no ápice e no corpo da língua. A papila fungiforme mostrou-se com superfície praticamente lisa e de formato irregular, com a presença de poros gustativos. Estas foram encontradas por toda a superfície dorsal, com maior concentração na parte rostral do ápice. Foram observadas apenas duas papilas valadas, dispostas na região da raiz da língua, com corpo rodeado por sulcos profundos e vários botões gustativos. As línguas de Bradypus variegatus apresentaram papilas linguais similares às descritas para outras espécies de Xenarthras e mamíferos selvagens...

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The Bradypus variegatus inhabits the forests of South America and feeds from leaves, branches and sprouts from different plants. Due to its diet and the lack of literature on the morphological aspect of Xenarthras, five Bradypus variegatus tongues from animals which died from natural causes were evaluated, and they came from Pará State Museum Emílio Goeldi and were donated to the Laboratory of Animal Morphological Research (LaPMA) from UFRA, for revealing the different types of papillae and epithelial-connective tissue. Macroscopically, the tongues presented elongated shape, rounded apex, body, root, median sulcus in the root's apex, and two vallate papillae. The mucous membrane of the tongue revealed a keratinized stratified pavement epithelium, while the ventral surface of the tongue was thin and smooth, not provided with any type of papillae. However, the dorsal surface of the tongue was irregular with the presence of three types of papillae: filiform, fungiform and vallate papillae. The filiform papillae found were of a simple type, presenting a rounded base, irregularly distributed with a larger concentration and development on the tongue's apex and body. The fungiform papilla showed a practically smooth surface with irregular format, with the presence of gustatory pores; these were found all over the dorsal surface, with larger concentration at the rostral part of the apex. Only two vallate papillae were observed disposed in the root of the tongue, surrounded by a deep groove, and revealing several taste buds. The tongues from Bradypus variegatus presented gustatory papillae similar to the ones described for other Xenarthras species and wild mammals.(AU)

A Bradypus variegatus habita florestas da América do Sul e alimenta-se de folhas, ramos e brotos de várias plantas. Em decorrência de sua dieta, bem como da escassez de literatura sobre aspectos morfológicos dos Xenarthras, avaliaram-se cinco línguas de Bradypus variegatus, que foram a óbito por causas naturais, provenientes do Museu Paraense Emílio Goeldi e doados ao Laboratório de Pesquisa Morfológica Animal (LaPMA) da UFRA, a fim de se elucidarem os diferentes tipos de papilas e a interface epitélio-tecido conjuntivo. Macroscopicamente, as línguas apresentaram formato alongado, ápice arredondado, corpo, raiz, sulco mediano do ápice à raiz e duas papilas valadas. A mucosa da língua revelou epitélio de revestimento pavimentoso estratificado queratinizado, enquanto a face ventral era delgada e lisa, desprovida de qualquer tipo de papila. Já a face dorsal apresentou-se irregular, com a presença de três tipos papilares: papilas filiformes, fungiformes e valadas. As papilas filiformes encontradas eram do tipo simples, com base circular, distribuídas irregularmente, com maior concentração e desenvolvimento no ápice e no corpo da língua. A papila fungiforme mostrou-se com superfície praticamente lisa e de formato irregular, com a presença de poros gustativos. Estas foram encontradas por toda a superfície dorsal, com maior concentração na parte rostral do ápice. Foram observadas apenas duas papilas valadas, dispostas na região da raiz da língua, com corpo rodeado por sulcos profundos e vários botões gustativos. As línguas de Bradypus variegatus apresentaram papilas linguais similares às descritas para outras espécies de Xenarthras e mamíferos selvagens.(AU)

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The cytoskeleton is a central and vital structure of eukaryotic cells. It consists of a dynamic network of partially interconnected polymers. This extended network controls the mechanical properties of animal cells, serves as intracellular transport "pathways", and plays a prominent role in cell motility, proliferation, and adhesion. In order to evaluate the action of laser irradiation on the cytoskeleton and proliferation of endothelial cells, rabbit aortic endothelial cells (RAEC) were irradiated with 685-nm low-level laser (20 mW output power). Fluorescent dye rhodamine-phalloidin staining was used to visualize the effect of laser irradiation on actin filaments. Irradiation with 8 J/cm(2) was performed four times at 12-h intervals for 24 min. Cells cultured under low fetal bovine serum condition (5% FBS) for 7 days presented actin staining predominantly in the cortical membrane region and a few actin filament stress fibers. However, the formation of stress fibers similar to those of control cells increased significantly in irradiated cells. It was concluded that laser irradiation induces changes in the cytoskeleton of endothelial cells through the reorganization of actin filaments and neo-formation of stress fibers, allowing evident cellular proliferation.

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Silybine (SBN), isosilybine (ISBN), silycristine (SCN), silydianine (SDN), and taxifoline (TXF) are the main active flavonoids commonly found in the dried fruits of Silybum marianum, Gaertner (Compositae). Concentrations of these compounds, except TXF, are usually expressed together as silymarin content. This paper describes a simple dissolution test developed to estimate silymarin (Sl) in pharmaceutical formulations. Five commercial products were tested using this new method (including tablets, sugar tablets, and capsules): two from Argentina, one from Brazil, one from Spain, and one from Italy. Results demonstrated that, provided the dosage form disintegrates, amounts dissolved range from 50 to 90% of the labeled value. Products were analyzed by high performance liquid chromatography (HPLC) and UV spectrophotometry.

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Thirty-five patients received a Capsure Z Medtronic bipolar model 5034 for the ventricle and 5534 for the atrium. These have 1.2 mm2 totally proprous, platinized, steroid eluting distal electrodes. The control group was repesented by 14 consective patients reciving CapSure SP medtronic model 5024 for the ventricle and 5524 for the atrium. At implant and during the follow-up period (6 months), CapSure Z and SP showed similar low pacing theresholds without early peaking in atrium (0.5 +/- 0.26 V vs 0 +/- 0.21 V at 0.5 msec P=NS., 0.06 +/- 0.01 msec at 1.6 V P=NS, respectively) and while Capsure Z showed a lewr value at six months in ventricle (0.3 +/- 0.1 V vs ).4 +/- 0.23 V P=NS, respectively) and while Capsure Z showed a lower value at six months in ventricle (0.3 +/- V vs 0.4 +/- 0.23 V P=NS at 0.5 msec, 0.07 +/- 0.03 msec. vs 0.1 +/- 0.02 msec. P<0.02 at 1.6V, repectively). P and R wave sensing of CapSure Z was better thant that of CapSure SP at implant (P wave + 5 +/- 2.5 mV vs 3.80 +/- 1.95 m;R wave = 15.2 +/- 6.4 mV vs 13.13 +/- 5.5 mV, respecitively) and during the follow-up period achieving statistical significance at the 6 th mont oly for P wave (P wave = 3.33 +/- 1.6 mV vs 2.61 +/- 1.05 mV P<0.05; R wave = 13.9 +/- 5.17 vs 10.8 +/- 5.75 mV, P=NS). CapSure Z atrial and ventricular pacing impedance were double than that of CapSure SP one at implant (atrium: 1050 +/- 214 vs 491 +/- 51; ventricle: 1296 +/- 236 vs 481 +/- 81, p< 0.0001) and during the follow-up period (atrium: 1081 +/- 185vs553 +/- 60; ventricle 1186 +/- 256 vs 656+/- 68, P< 0.0001).

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