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Sub-mesoscale and mesoscale (i.e., 1-10 km and 10-200 km, respectively) ocean processes are highly relevant for the understanding of global circulation, mixing of water masses and energy exchange between ocean layers. However, the processes happening at these scales are hard to be characterized using direct measurements of temperature and salinity. Direct measurements are obtained from vertical probes and/or autonomous vehicles, which, despite their high vertical resolution, are sparsely located in space and therefore unable to capture spatial details at these scales. Seismic oceanography (SO) data have been successfully used to imaging and characterize the ocean at these spatial scales. These data represent indirect measurements of the ocean temperature and salinity along kilometric transects with high horizontal resolution (i.e., a near-synaptic view of the system under investigation), but lower vertical resolution when compared with direct observations. Despite its complex oceanographic setting, the Madeira Abyssal Plain is still largely uncharacterized due to the lack of direct observations. We show for the first time a comprehensive processing, modelling and interpretation of three 2-D seismic oceanography sections from this region. The data show coherent seismic reflection in space, depth and time and shed light into this oceanographic setting with an unprecedent horizontal resolution. The SO modelling and interpretation are combined with existing direct measurements and a quantitative method to correlate thermohaline staircases interpreted from conductivity-temperature-depth casts and seismic reflections is proposed. The results show the relatively stable presence of thermohaline staircases in simultaneously time and space between 1200 and 2000 m of water depth and their spatial variability and contribute to the generalization of SO in physical oceanography.
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Schistosomiasis is a parasitic infection of great prevalence worldwide, affecting 250 million people in 78 countries. Faced with this problem, studies that seek to analyze molluscicidal activity from plant extracts have stood out. The present work aimed to obtain the phytochemical characterization and investigate the molluscicidal activity in the hydroalcoholic extract of Ricinus communis leaves on Biomphalaria glabrata. The hydroalcoholic extract was prepared by macerated with solvent ethanol P.A 96%, followed by filtration and concentration in rotary evaporator. Next, five groups of snails with 10 animals each, one being the negative control group, were submitted to treatments with four concentrations of 25, 50, 75 and 100 mg/L of hydroalcoholic extract of R. communis. The parameters mortality, physiological and behavioral aspects of mollusks were analyzed during 96h. The chemical characterization of the extract was performed by high-performance liquid chromatography coupled to mass spectrometry (LC-MS). Chemical characterization revealed the presence of tannins, flavonoids and ricinin alkaloid, but under the conditions analyzed, the presence of saponins was not observed. There was no significant molluscicidal activity of the extract. However, a greater influence was observed in the diet, in addition to the motility and physiological state of the snails (alteration of cephalopodal mass and oviposition). The toxicity test was performed with Artemia salina and no toxicity was observed for this microcrustacean. It is expected that the results obtained contribute to the fight against the expansion of schistosomiasis and that they make room for other studies that investigate the molluscicidal action of plant extracts.
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Biomphalaria , Euphorbiaceae , Moluscocidas , Esquistossomose , Animais , Feminino , Biomphalaria/parasitologia , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Moluscocidas/farmacologia , Compostos Fitoquímicos/farmacologia , RicinusRESUMO
Schistosomiasis is considered one of the Neglected Tropical Diseases (NTDs), which affects around 240 million people worldwide. In Brazil, Schistosomiasis mansoni has been registered in 19 states, predominantly in rural areas. This study aimed to analyze the spatial distribution of Schistosomiasis mansoni cases in the Maranhao State from 2007 to 2016, as well as the temporal trend over this period. The data were obtained from secondary sources: Schistosomiasis Control Program of Maranhao (PCE-MA) and Information System for Notifiable Diseases (SINAN). The State Health Regions (HRs) were considered analysis units. Maranhao had a positivity rate of 3.8 for the period. The Regions that presented the highest percentages of positivity in the state were Pinheiro (7.92), Ze Doca (3.30), and Viana (3.10). Municipalities such as Bacuri, Serrano do Maranhao, and Bequimao, located in the Pinheiro HR, showed positivity rates of 16.56, 13.31, and 11.01 respectively. The spatial analysis of schistosomiasis cases showed that Maranhao has two main centers for the spread of the disease, both located in the northern portion of the state, namely the Baixada Maranhense and the east coast. This study concluded that the positivity of Schistosomiasis mansoni in Maranhao was stable over the analyzed period. The state still maintains the Baixada Maranhense micro-region as an important area for the spread of the disease reaching socially vulnerable population groups.
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Esquistossomose mansoni , Esquistossomose , Animais , Brasil/epidemiologia , Humanos , Doenças Negligenciadas/epidemiologia , Prevalência , Schistosoma mansoni , Esquistossomose mansoni/epidemiologia , Análise EspacialRESUMO
ABSTRACT Schistosomiasis is considered one of the Neglected Tropical Diseases (NTDs), which affects around 240 million people worldwide. In Brazil, Schistosomiasis mansoni has been registered in 19 states, predominantly in rural areas. This study aimed to analyze the spatial distribution of Schistosomiasis mansoni cases in the Maranhao State from 2007 to 2016, as well as the temporal trend over this period. The data were obtained from secondary sources: Schistosomiasis Control Program of Maranhao (PCE-MA) and Information System for Notifiable Diseases (SINAN). The State Health Regions (HRs) were considered analysis units. Maranhao had a positivity rate of 3.8 for the period. The Regions that presented the highest percentages of positivity in the state were Pinheiro (7.92), Ze Doca (3.30), and Viana (3.10). Municipalities such as Bacuri, Serrano do Maranhao, and Bequimao, located in the Pinheiro HR, showed positivity rates of 16.56, 13.31, and 11.01 respectively. The spatial analysis of schistosomiasis cases showed that Maranhao has two main centers for the spread of the disease, both located in the northern portion of the state, namely the Baixada Maranhense and the east coast. This study concluded that the positivity of Schistosomiasis mansoni in Maranhao was stable over the analyzed period. The state still maintains the Baixada Maranhense micro-region as an important area for the spread of the disease reaching socially vulnerable population groups.
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Há pouca prática de atividades motoras sistematizadas em classes de berçário. Objetivou-se implantar um programa de atividade motora com música para bebês. Foi realizada uma pesquisa-ação, em uma classe de berçário com seis bebês, seus respectivos pais e professores, em duas temáticas: imitação de animais e exploração de materiais. Observou-se que os bebês realizaram habilidades motoras básicas que possibilitaram expressões de diferentes ritmos musicais, imitação de animais, expressão de emoções e utilização de diferentes vias neuronais. Houve bom entrosamento entre professores, pais e pesquisadores. Considera-se, assim, que atividades com música podem ser empregadas em classes de berçário para oportunizar vivências motoras de forma lúdica, as quais são importantes para o desenvolvimento integral.
Systematized motor practice is scarce in nursery classes. This study aimed to offer a program with motor activity and music for babies. An action research was carried out in a nursery class with six infants, their respective parents and teachers, in two themes: imitation of animals and exploration of materials. It was observed that infants performed basic motor skills that allowed expressions of different musical rhythms, imitation of animals, expression of emotions and stimulation of different neuronal pathways; there was good interaction between teachers, parents and researchers. It is considered, therefore, that activities with music can be used in nursery classes to offer motor experiences in a playful way, which are important for integral development.
La práctica de actividades motoras sistematizadas es escasa en clases de guardería. Se trató de implantar un programa de ejercicios con música y movimiento activo para bebés. Se realizó una investigación-acción, en una clase guardería con seis bebés, sus respectivos padres y profesores, en dos temáticas: imitación de animales y exploración de materiales. Se observó que los bebés realizaron habilidades motoras básicas que posibilitaran expresiones de diferentes ritmos musicales, imitación de animales, expresión de emociones y estimulación de diferentes vías neuronales; hubo un buen entendimiento entre profesores, padres e investigadores. Se considera, así, que actividades con música pueden ser empleadas en clases de guardería para dar vivencias motoras de forma lúdica, las cuales son importantes para el desarrollo integral.
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Humanos , Lactente , Exercício Físico , Creches , Desenvolvimento Infantil , MúsicaRESUMO
Salt marshes support estuarine biodiversity and provide ecosystem services; however, their general decay is being observed worldwide, in large part due to land reclamation. Accordingly, there is a growing concern about salt marsh preservation status having in mind the promotion of effective management decisions towards their conservation and restoration. Satellite imagery offers the opportunity to monitor land surface dynamics, constituting a fundamental information source for wetland monitoring. This study analyses spatial and temporal vegetation changes within Ria de Aveiro coastal lagoon between 1984 and 2017, by processing and analyzing TM and ETM+ Landsat imagery. A database consisting of 264 cloud-free images was collected and analyzed. The Normalized Difference Water Index was computed using the remote surface reflectance and was then used to distinguish land from water and to estimate the flooded lagoon area. Moreover, the tidal state was determined for each image from a tidal elevation record monitored at the lagoon entrance. Subsequently, four vegetation indices (VI) were computed and their spatial variability in the lagoon area uncovered by water was assessed. Spatially averaged spectral indices were also statistically analyzed and seasonal variations and interannual trends evaluated. Results show that the intertidal area increased, and VI values decreased indicating a possible reduction in the Chlorophyll content and suggesting that the new intertidal regions are mostly covered by mud. The spatially averaged VI values show seasonal patterns, with peaks in spring and summer, coinciding with high biomass productivity periods. The largest flooded area and VI modifications occurred after 1999, suggesting that changes are associated with dredging activities performed in the main lagoon channels. This study reinforced the potential of Landsat archives to monitor coastal wetlands, highlighting their importance for coastal managers of threatened systems, and therefore helping to define management strategies about the ecological conservation of estuarine systems.
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Biota , Monitoramento Ambiental , Fenômenos Fisiológicos Vegetais , Imagens de Satélites , Áreas Alagadas , Estuários , Dinâmica Populacional , Portugal , Estações do AnoRESUMO
Currents, wind, bathymetry, and freshwater runoff are some of the factors that make coastal waters heterogeneous, patchy, and scientifically interesting-where it is challenging to resolve the spatiotemporal variation within the water column. We present methods and results from field experiments using an autonomous underwater vehicle (AUV) with embedded algorithms that focus sampling on features in three dimensions. This was achieved by combining Gaussian process (GP) modeling with onboard robotic autonomy, allowing volumetric measurements to be made at fine scales. Special focus was given to the patchiness of phytoplankton biomass, measured as chlorophyll a (Chla), an important factor for understanding biogeochemical processes, such as primary productivity, in the coastal ocean. During multiple field tests in Runde, Norway, the method was successfully used to identify, map, and track the subsurface chlorophyll a maxima (SCM). Results show that the algorithm was able to estimate the SCM volumetrically, enabling the AUV to track the maximum concentration depth within the volume. These data were subsequently verified and supplemented with remote sensing, time series from a buoy and ship-based measurements from a fast repetition rate fluorometer (FRRf), particle imaging systems, as well as discrete water samples, covering both the large and small scales of the microbial community shaped by coastal dynamics. By bringing together diverse methods from statistics, autonomous control, imaging, and oceanography, the work offers an interdisciplinary perspective in robotic observation of our changing oceans.
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This study evaluated the effects of hyaluronic acid (HA) on bone repair of human dental sockets. Thirty-two lower first premolars were extracted from 16 patients (2 per patient) for orthodontic reasons. Following the extractions, one socket was randomly filled with 1% HA gel, while the other was allowed to naturally fill with blood clot. After 30 and 90 days of surgery, patients underwent cone beam computed tomography. Five central orthoradial slices were captured from each socket. The gray intensity was measured in each image and results were reported as mean percentage of bone formation. The buccolingual alveolar ridge width was measured and dimensional changes were compared between the postoperative intervals. The pattern of alveolar trabecular bone was evaluated through the fractal dimension. Treated sockets showed a higher percentage of bone formation and fractal dimension values (58.17% and 1.098, respectively) compared with controls (48.97% and 1.074, respectively) in the 30-day postoperative period (p < 0.05). After 90 days, there was no significant difference between groups. Additionally, no significant difference was found between groups regarding the alveolar dimensions (p > 0.05). Use of 1% HA gel after tooth extraction accelerates bone repair in human dental sockets.
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Regeneração Óssea/efeitos dos fármacos , Ácido Hialurônico/farmacologia , Extração Dentária/métodos , Alvéolo Dental/efeitos dos fármacos , Alvéolo Dental/fisiologia , Adolescente , Adulto , Dente Pré-Molar , Criança , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Masculino , Osteogênese/efeitos dos fármacos , Osteogênese/fisiologia , Período Pós-Operatório , Reprodutibilidade dos Testes , Estatísticas não Paramétricas , Fatores de Tempo , Alvéolo Dental/diagnóstico por imagem , Resultado do Tratamento , Adulto JovemRESUMO
Schistosomiasis is a disease of global extent reaching populations in social vulnerability. One of the control measures of this parasitosis is the use of molluscicidal substances that can fight snails of the genus Biomphalaria, intermediate hosts of Schistosoma mansoni. The aim of this work was to study the toxic activity of three mangrove species (Avicennia schaueriana Stapf. & Leech, ex Moldenke, 1939, Laguncularia racemosa (L.) CF Gaertn, 1807 and Rhizophora mangle L. 1753) on the biological activities of snails Biomphalaria glabrata. Hydroalcoholic extracts were prepared from the stem and leaves of each of the three plant species to which mollusks were exposed. The phytochemical analysis of plants showed the presence of important metabolites in the leaves and stems of L. racemosa and R. mangle, such as tannins and saponins, but the absence of these metabolites in A. schaueriana. Leaf and stem extracts of the three plant species showed low molluscicidal activity, not reaching the standards determined by the World Health Organization (WHO, 1983). L. racemosa and R. mangle has interfered with motility, feeding and oviposition of snails, unlike the extracts of A. schaueriana, which had no effect on these activities.
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Avicennia/química , Biomphalaria/efeitos dos fármacos , Combretaceae/química , Moluscocidas/farmacologia , Extratos Vegetais/farmacologia , Rhizophoraceae/química , Animais , Moluscocidas/isolamento & purificaçãoRESUMO
Abstract This study evaluated the effects of hyaluronic acid (HA) on bone repair of human dental sockets. Thirty-two lower first premolars were extracted from 16 patients (2 per patient) for orthodontic reasons. Following the extractions, one socket was randomly filled with 1% HA gel, while the other was allowed to naturally fill with blood clot. After 30 and 90 days of surgery, patients underwent cone beam computed tomography. Five central orthoradial slices were captured from each socket. The gray intensity was measured in each image and results were reported as mean percentage of bone formation. The buccolingual alveolar ridge width was measured and dimensional changes were compared between the postoperative intervals. The pattern of alveolar trabecular bone was evaluated through the fractal dimension. Treated sockets showed a higher percentage of bone formation and fractal dimension values (58.17% and 1.098, respectively) compared with controls (48.97% and 1.074, respectively) in the 30-day postoperative period (p < 0.05). After 90 days, there was no significant difference between groups. Additionally, no significant difference was found between groups regarding the alveolar dimensions (p > 0.05). Use of 1% HA gel after tooth extraction accelerates bone repair in human dental sockets.
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Humanos , Masculino , Feminino , Criança , Adolescente , Adulto , Adulto Jovem , Extração Dentária/métodos , Regeneração Óssea/efeitos dos fármacos , Alvéolo Dental/efeitos dos fármacos , Alvéolo Dental/fisiologia , Ácido Hialurônico/farmacologia , Osteogênese/efeitos dos fármacos , Osteogênese/fisiologia , Período Pós-Operatório , Fatores de Tempo , Dente Pré-Molar , Reprodutibilidade dos Testes , Resultado do Tratamento , Estatísticas não Paramétricas , Alvéolo Dental/diagnóstico por imagem , Tomografia Computadorizada de Feixe CônicoRESUMO
It has been reported that carbon nanotubes (CNTs) serve as nucleation sites for the deposition of bone matrix and cell proliferation. Here, we evaluated the effects of multi-walled CNTs (MWCNTs) on bone repair of rat tibiae. Furthermore, because sodium hyaluronate (HY) accelerates bone restoration, we associated CNTs with HY (HY-MWCNTs) in an attempt to boost bone repair. The bone defect was created by a 1.6-mm-diameter drill. After 7 and 14 days, tibiae were processed for histological and morphometric analyses. Immunohistochemistry was used to evaluate the expression of vascular endothelial growth factor (VEGF) in bone defects. Expression of osteocalcin (OCN), bone morphogenetic protein-2 (BMP-2), and collagen I (Col I) was assessed by real-time PCR. Histomorphometric analysis showed a similar increase in the percentage of bone trabeculae in tibia bone defects treated with HY and HY-MWCNTs, and both groups presented more organized and thicker bone trabeculae than nontreated defects. Tibiae treated with MWCNTs or HY- MWCNTs showed a higher expression of VEGF. Treatment with MWCNTs or HY-MWCNTs increased the expression of molecules involved in the bone repair process, such as OCN and BMP-2. Also, HY- and MWCNT-treated tibiae had an increased expression of Col I. Thus, it is tempting to conclude that CNTs associated or not with other materials such as HY emerged as a promising biomaterial for bone tissue engineering.
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Osso e Ossos/metabolismo , Ácido Hialurônico/farmacologia , Nanotubos de Carbono/análise , Fator A de Crescimento do Endotélio Vascular/metabolismo , Cicatrização/fisiologia , Animais , Ratos , Ratos WistarRESUMO
On 5 November 2015, the Fundão tailings dam collapsed and its content first reached River Doce and then the Atlantic Ocean by 22 November. This study focuses on the oceanic time and space patterns of river discharge dispersion. By using an ocean model together with nLw(555) and RGB images from MODIS sensors, the river plume was followed for 2months after the arrival of the tailings at the ocean. The results show the huge effect of this accident and reveal that riverine waters may have dispersed hundreds of kilometres, reaching regions as far as the shelf in front of the city of Rio de Janeiro. The movement of the freshwater was essentially to the south in accordance with the seasonal wind regime. Episodic frontal systems, leading to wind reversion, and oceanic mesoscale features contribute to the offshore dispersion of the plume. The region more often in contact with the riverine waters was located at the inner shelf between the river mouth and the city of Vitória, turning to the outer shelf and shelf break at lower latitudes.
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Desastres , Modelos Teóricos , Rios/química , Água do Mar/química , Colapso Estrutural , Movimentos da Água , Oceano Atlântico , Brasil , Estações do Ano , VentoRESUMO
The action of extracts from the stem, leaves, and fruit of Jatropha gossypiifolia on Biomphalaria glabrata was studied by analyzing survival, feeding capacity and oviposition ability. The extracts were obtained by macerating the plant parts in 92% ethanol, which were then evaporated until a dry residue was obtained and phytochemically studied. The molluscicidal activity on B. glabrata was investigated using the procedures recommended by WHO (1965). The amount of food ingested and oviposition were measured during each experiment. The extract of leaves from J. gossypiifolia was shown to be a strong molluscicidal agent, causing 100% mortality of B. glabrata, even in the lowest concentration tested, of 25 ppm. Regarding the fruit extract, there was variation in the mortality, depending on the concentration used (100, 75, 50 and 25 ppm). The snails that were in contact with the fruit extract had significant reduction in feeding and number of embryos in comparison to the control. The stem extract did not present molluscicidal activity nor had any influence on the feeding and oviposition abilities of B. glabrata, in the concentrations tested. In conclusion, the extracts of leaves and fruits of J. gossypiifolia investigated in this work show molluscicidal effect and may be sources of useful compounds for the schistosomiasis control.
Estudou-se a ação dos extratos do caule, folhas e frutos de Jatropha gossypiifolia (Pinhão-roxo) sobre Biomphalaria glabrata analisando a sobrevivência, capacidade alimentar e de oviposição. Os extratos foram obtidos pela maceração das partes do vegetal em álcool etílico 92%, evaporados até obter-se um resíduo seco e estudados fitoquimicamente. A atividade moluscicida em B. glabrata seguiu os procedimentos recomendados pela WHO (1965). A medida de quantidade de alimento ingerido e a oviposição foi realizada durante cada experimento. O extrato das folhas de J. gossypiifolia mostrou-se um forte agente moluscicida, promovendo 100% de mortalidade de B. glabrata mesmo na menor concentração testada, 25 ppm. Com o extrato dos frutos houve variação na mortalidade, de acordo com a concentração utilizada (100, 75, 50 e 25 ppm). Os caramujos em contato com o extrato dos frutos apresentaram quando comparado ao controle uma diminuição significativa nos comportamentos alimentares e de número de embriões. O extrato do caule não apresentou atividade moluscicida e nenhuma influência sobre a capacidade alimentar e de oviposição de B. glabrata nas concentrações testadas. Em conclusão, os extratos de folhas e frutos de J. gossypiifolia investigados neste trabalho apresentam efeito moluscicida e possivelmente podem ser fontes de compostos no controle da esquistossomose.
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Animais , Feminino , Biomphalaria/efeitos dos fármacos , Jatropha/química , Moluscocidas/farmacologia , Extratos Vegetais/farmacologia , Comportamento Alimentar/efeitos dos fármacos , Oviposição/efeitos dos fármacos , SobrevidaRESUMO
The Minho River, situated 30 km south of the Rias Baixas, is the most important freshwater source flowing into the Western Galician coast (NW of the Iberian Peninsula). The buoyancy generated by the Minho estuarine plume can reverse the normal circulation pattern inside the Rias Baixas affecting the exchange between the Rias and the ocean, changing the input of nutrients. Nevertheless, this inversion of the circulation patterns is not a well-monitored phenomenon. The only published results based on in situ data related to the presence of the Minho River plume inside the Rias de Vigo and Pontevedra correspond to an event measured on spring 1998. In this case unexpectedly higher inflow surface current velocities were found at the Ria de Pontevedra, located further away from Minho River. Thus, the main aim of this study is to research the main factors inducing this unusual pattern on the circulation of the Rias de Vigo and Pontevedra. A numerical model implementation of MOHID previously developed, calibrated, and validated for this coastal area was used. Several scenarios were performed in order to explain the individual effect of the Minho River, rivers discharging into each Rias, and estuarine morphology changes. According to the model results, the Minho River discharge is a key factor in the establishment of the negative circulation, while small rivers inside the Rias slightly attenuate this circulation. The negative circulation was stronger in Ria de Pontevedra independently of the distance of this coastal system from the Minho River mouth, showing that morphologic estuarine features are the main factor justifying the different local circulation patterns.
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Monitoramento Ambiental , Água Doce , Rios , GeografiaRESUMO
The action of extracts from the stem, leaves, and fruit of Jatropha gossypiifolia on Biomphalaria glabrata was studied by analyzing survival, feeding capacity and oviposition ability. The extracts were obtained by macerating the plant parts in 92% ethanol, which were then evaporated until a dry residue was obtained and phytochemically studied. The molluscicidal activity on B. glabrata was investigated using the procedures recommended by WHO (1965). The amount of food ingested and oviposition were measured during each experiment. The extract of leaves from J. gossypiifolia was shown to be a strong molluscicidal agent, causing 100% mortality of B. glabrata, even in the lowest concentration tested, of 25 ppm. Regarding the fruit extract, there was variation in the mortality, depending on the concentration used (100, 75, 50 and 25 ppm). The snails that were in contact with the fruit extract had significant reduction in feeding and number of embryos in comparison to the control. The stem extract did not present molluscicidal activity nor had any influence on the feeding and oviposition abilities of B. glabrata, in the concentrations tested. In conclusion, the extracts of leaves and fruits of J. gossypiifolia investigated in this work show molluscicidal effect and may be sources of useful compounds for the schistosomiasis control.
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Biomphalaria/efeitos dos fármacos , Jatropha/química , Moluscocidas/farmacologia , Extratos Vegetais/farmacologia , Animais , Comportamento Alimentar/efeitos dos fármacos , Feminino , Dose Letal Mediana , Oviposição/efeitos dos fármacos , SobrevidaRESUMO
Tissue engineering has emerged as a novel treatment for replacement of lost bone tissue. This study evaluated the effects of a chitosan-gelatin scaffold seeded with bone marrow mesenchymal stem cells (BMMSCs) in the healing process of tooth sockets in rats. BMMSCs isolated from transgenic rats expressing enhanced green fluorescent protein (eGFP) were expanded and seeded on a chitosan-gelatin scaffold. These constructs were cultured for three days and characterized by scanning electronic microscopy (SEM) and energy dispersion spectroscopy (EDS). Receptor rats received the implant in the left sockets, after upper first-molar extraction. Right alveoli served as control. Animals were sacrificed at days 5, 21, and 35 post-graft for examination. Morphometry demonstrated increased bone mineralization after 21 and 35 days in transplanted sockets. Migration, differentiation, and fate of eGFP-labeled BMMSCs were monitored by immunohistochemistry. Tartrate-resistant acid phosphatase staining (TRAP) was carried out at 21 days, to identify the involvement of osteoclastic cells in the scaffold resorption. The biomaterial was resorbed by TRAP-negative giant cells in a typical foreign body reaction. Immunohistochemical findings showed that BMMSCs contributed to bone, epithelial, and vascular repair. Together, results indicate that BMMSCs loaded in the chitosan-gelatin scaffold is a strategy for tissue development in bone engineering.
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Processo Alveolar/efeitos dos fármacos , Processo Alveolar/fisiologia , Regeneração Óssea/efeitos dos fármacos , Quitosana/farmacologia , Gelatina/farmacologia , Células-Tronco Mesenquimais/citologia , Alicerces Teciduais/química , Fosfatase Ácida/metabolismo , Processo Alveolar/diagnóstico por imagem , Processo Alveolar/patologia , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/ultraestrutura , Transplante Ósseo , Forma Celular/efeitos dos fármacos , Proteínas de Fluorescência Verde/metabolismo , Imuno-Histoquímica , Isoenzimas/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/ultraestrutura , Porosidade , Ratos , Ratos Endogâmicos Lew , Coloração e Rotulagem , Fosfatase Ácida Resistente a Tartarato , Tomografia Computadorizada por Raios XRESUMO
AIMS: Sodium hyaluronate (HY) accelerates the repair of bone defects. However, the weak stability of HY formulations in aqueous environments has hindered its wide utilization. The functionalization of carbon nanotubes (SWCNT) with HY (HY-SWCNT) results in a reinforced hydrogel with an increased stability. Nevertheless, the biological effects of HY-SWCNT have not been explored. Thus, our objective was to evaluate whether this biomaterial preserves the bioactivity of the HY. MAIN METHODS: Wistar rats were subjected to molar extraction and the sockets were treated with SWCNT (50-400 microg/mL), 1% HY, HY-SWCNT (50-400 microg/mL) or carbopol (vehicle). After seven days of surgery, histological and morphometric analyses were performed to evaluate the trabecular bone formation and the number of cell nuclei in the sockets. Expression of collagen types I and III was determined by immunohistochemistry. KEY FINDINGS: Treatment with SWCNT did not alter the bone deposition, as well as the cell nuclei counting. Additionally, no significant evidence of toxicity was observed in SWCNT-treated sockets. Contrastingly, both HY and HY-SWCNT induced a marked increase in the bone formation (HY: 10.10+/-1.99%; HY-SWCNT 100 microg/mL: 10.90+/-1.13%; control: 3.69+/-1.17%) and decreased the cell nuclei amount in the sockets. Moreover, collagen type I expression was more pronounced in HY- and HY-SWCNT-treated sockets. No significant differences were viewed in the expression of collagen type III. SIGNIFICANCE: Our results indicate that SWCNT is a feasible material to deliver HY to bone defects. Importantly, the functionalization of SWCNT with HY preserved the beneficial biological properties of HY in the healing process, thereby suggesting that HY-SWCNT scaffolds are potentially useful biomaterials for the restoration of bone defects.
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Materiais Biocompatíveis/metabolismo , Ácido Hialurônico/metabolismo , Nanotubos de Carbono/química , Osteogênese , Animais , Materiais Biocompatíveis/química , Regeneração Óssea , Colágeno Tipo I/metabolismo , Colágeno Tipo III/metabolismo , Ácido Hialurônico/química , Masculino , Dente Molar/cirurgia , Nanotubos de Carbono/ultraestrutura , Ratos , Ratos Wistar , CicatrizaçãoRESUMO
OBJECTIVE: In this study we evaluated the effects of sodium hyaluronate (HY) in the healing process of tooth sockets of rats. DESIGN: Immediately after the extraction of the upper first molars of male Holtzman rats, right sockets were treated with 1% HY gel (approximately 0.1 ml), while left sockets were used as control (blood clot). The animals were sacrificed at 2, 7, and 21 days after tooth extraction and upper maxillaries processed for histological and morphometric analysis of the apical and medium thirds of the sockets. Carbopol, an inert gel, was used to evaluate the mechanical effect of gel injection into sockets. Expression of bone morphogenetic protein-2 (BMP-2) and osteopontin (OPN) was determined by immunohistochemistry at 1, 2, 3, 4, 5, and 7 days after tooth extraction. RESULTS: Histological analysis showed that HY treatment induced earlier trabecular bone deposition resulting in a bone matrix more organized at 7 and 21 days after tooth extraction. Also, HY elicited significant increase in the amount of bone trabeculaes at 7 and 21 days after tooth extraction (percentage of trabecular bone area at 7 days: 13.21+/-4.66% vs. 2.58+/-1.36% in the apical third of control sockets) and in the vessels counting at 7 days. Conversely, the number of cell nuclei was decreased in HY-treated sockets. Additionally, expression of BMP-2 and OPN was enhanced in HY-treated sockets compared with control sockets. CONCLUSIONS: These findings suggest that HY accelerates the healing process in tooth sockets of rats stimulating the expression of osteogenic proteins.