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The role of macroalgae (seaweed) as a global contributor to carbon drawdown within marine sediments - termed 'blue carbon' - remains uncertain and controversial. While studies are needed to validate the potential for macroalgalcarbon sequestration in marine and coastal sediments, fundamental questions regarding the fate of dislodged macroalgal biomass need to be addressed. Evidence suggests macroalgal biomass may be advected and deposited within other vegetated coastal ecosystems and down to the deep ocean; however, contributions to near-shore sediments within coastal waters remain uncertain. In this study a combination of eDNA metabarcoding and surficial sediment sampling informed by seabed mapping from different physical environments was used to test for the presence of macroalgal carbon in near-shore coastal sediments in south-eastern Australia, and the physical factors influencing patterns of macroalgal transport and deposition. DNA products for a total of 68 macroalgal taxa, representing all major macroalgal groups (Phaeophyceae, Rhodophyta, and Chlorophyta) were successfully detected at 112 near-shore locations. These findings confirm the potential for macroalgal biomass to be exported into near-shore sediments and suggest macroalgal carbon donors could be both speciose and diverse. Modelling suggested that macroalgal transport and deposition, and total organic carbon (TOC), are influenced by complex interactions between several physical environmental factors including water depth, sediment grain size, wave orbital velocity, current speed, current direction, and the extent of the infralittoral zone around depositional areas. Extrapolation of the optimised model was used to predict spatial patterns of macroalgal deposition and TOC across the coastline and to identify potentially important carbon sinks. This study builds on recent studies providing empirical evidence for macroalgal biomass deposits in near-shore sediments, and a framework for predicting the spatial distribution of potential carbon sinks and informing future surveys aimed at determining the potential for long-term macroalgal carbon sequestration in marine sediments.
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Chlorophyta , Rhodophyta , Algas Marinas , Ecosistema , Carbono , Sedimentos GeológicosRESUMEN
A comprehensive dataset of 138 surficial sediment samples retrieved from the shallow marine waters of six secondary compartments off the western coast of Victoria, Australia, is presented. Samples were collected between October 2018 and November 2020 at water depths ranging from four to 55 m using Shipek and Van Veen grabs. Sampling design targeted unconsolidated areas of the seafloor based on bathymetric and seafloor habitat data. Retrieved sediments were subsampled and subject to grain size analysis using a combination of dry sieving and laser diffraction methods, carbonate and organic matter content determination via Loss-on-Ignition, colour description using a Munsell chart, and roundness analysis using microscopic photography. This dataset, the most comprehensive surficial shallow water sedimentary record of the Otway Shelf, serves as a benchmark to understand sediment dynamics and conectivity along the coast, and can be used in environmental and engineering studies to support a range of management decisions.
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Vaccines induce antibodies, but T cell responses are also important for protection against Coronavirus disease 2019. Here, we analyzed the frequency of memory T cells in infected and/or vaccinated individuals and observed a decrease in central memory T cells in individuals who were vaccinated following COVID-19 infection.
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Linfocitos T CD8-positivos , Vacunas contra la COVID-19 , COVID-19 , Anticuerpos Antivirales , Linfocitos T CD8-positivos/citología , COVID-19/prevención & control , Vacunas contra la COVID-19/inmunología , Humanos , Células T de Memoria/citología , VacunaciónRESUMEN
Sandy beaches are highly dynamic systems which provide natural protection from the impact of waves to coastal communities. With coastal erosion hazards predicted to increase globally, data to inform decision making on erosion mitigation and adaptation strategies is becoming critical. However, multi-temporal topographic data over wide geographical areas is expensive and time consuming and often requires highly trained professionals. In this study we demonstrate a novel approach combining citizen science with low-cost unmanned aerial vehicles that reliably produces survey-grade morphological data able to model sediment dynamics from event to annual scales. The high-energy wave-dominated coast of south-eastern Australia, in Victoria, is used as a field laboratory to test the reliability of our protocol and develop a set of indices to study multi-scale erosional dynamics. We found that citizen scientists provide unbiased data as accurate as professional researchers. We then observed that open-ocean beaches mobilise three times as much sediment as embayed beaches and distinguished between slowed and accelerated erosional modes. The data was also able to assess the efficiency of sand nourishment for shore protection. Our citizen science protocol provides high quality monitoring capabilities, which although subject to important legislative preconditions, it is applicable in other parts of the world and transferable to other landscape systems where the understanding of sediment dynamics is critical for management of natural or anthropogenic processes.
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SUMMARY: Mesenchymal stem cells are characterized by in vitro high proliferation and multilineage potential maintenance. This study aimed to isolate and characterize equine YS mesenchymal stem cells and compare these with amniotic membranes. The yolk sac (YS) and amniotic membranes (AM) were obtained from 20 pregnant mares with gestational age around 30 days. Cells were cultured in α-MEM supplemented with 15 % FBS, 1 % antibiotic solution, 1 % L-glutamine and 1 % nonessential amino acids. To cell characterization we used cytogenetic analysis, fibroblast colony-forming unit assays, cell growth curves, immunophenotyping, flow cytometry, differentiation assays and teratoma formation. Results: Both cell sources presented fibroblastoid and epithelioid-like format. The YS cells have lower colony formation potential then AM ones, 3 versus 8 colonies per 103 plated cells. However, YS cells grew progressively while AM cells showed steady. Both, the YS and amnion cells immunolabeled for Oct-4, Nanog, SSEA-3, cytokeratin 18, PCNA, and vimentin. In addition, presented mesenchymal, hematopoietic, endothelial and pluripotency markers in flow cytometry. Discussion: Both cell sources presented high plasticity and differed into osteogenic, adipogenic, and chondrogenic lineages, and no tumor formation in nude mice was observed. The results suggest that horse YS may be useful for cell therapy such as amnion-derived cells.
RESUMEN: Las células madre mesenquimales se caracterizan por una alta proliferación in vitro y un mantenimiento potencial de múltiples líneas. Este estudio tuvo como objetivo aislar y caracterizar las células madre mesenquimales del saco vitelino equinas y compararlas con las membranas amnióticas. Se obtuvo el saco vitelino (SV) y las membranas amnióticas (MA) de 20 yeguas preñadas con edad gestacional de aproximadamente 30 días. Las células se cultivaron en α -MEM suplementado con 15 % de FBS, 1 % de solución antibiótica, 1 % de L-glutamina y 1 % de aminoácidos no esenciales. Para la caracterización celular utilizamos análisis citogenéticos, ensayos de unidades de colonias de fibroblastos, curvas de crecimiento celular, inmunofenotipaje, citometría de flujo, ensayos de diferenciación y formación de teratomas. Ambas fuentes celulares presentaron formato fibroblastoideo y epitelioide. Las células SV tienen un potencial de formación de colonias más bajo que las de MA, 3 versus 8 colonias por 103 células en placa. Sin embargo, las células SV crecieron progresivamente mientras que las células MA se mostraron estables. Tanto las células YS como las células amnios están inmunomarcadas para Oct-4, Nanog, SSEA-3, citoqueratina 18, PCNA y vimentina. Además, presentó marcadores mesenquimales, hematopoyéticos, endoteliales y pluripotenciales en citometría de flujo. Ambas fuentes celulares presentaron alta plasticidad y diferían en linajes osteogénicos, adipogénicos y condrogénicos, y no se observó formación de tumores en ratones. Los resultados sugieren que el SV de caballo puede ser útil para la terapia celular, como las células derivadas de amnios.
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Animales , Saco Vitelino/citología , Células Madre Mesenquimatosas/citología , Caballos , Saco Vitelino/embriología , Técnicas In Vitro , Células Cultivadas , Inmunofenotipificación , Medicina Regenerativa , Desarrollo Embrionario , Citometría de Flujo , AmniosRESUMEN
SUMMARY: The vomeronasal organ (VNO) is an accessory organ involved on the olfactory pathway, that detects pheromones and emits signals in order to modulate social and reproductive behavior. The VNO stem cells replace neurons throughout life. The aim of this study was to isolate and characterize cells derived from the vomeronasal organ from New Zealand rabbits. Five male rabbits with 120 days were used for cell isolation and culture. Results: VNO-derived cells presented labelling for proliferation (PCNA), undifferentiated profile (Nanog), neuronal (GFAP), mesenchymal stem cells (CD73, CD90 and CD105 and Stro-1). Also, presence of cytoskeletal (Vimentin, b-tubulin and CK-18) and absence of hematopoietic markers (CD34, CD117 and CD45) both by immunofluorescence and flow cytometry. By PCR it was possible to verify the expression of some undifferentiated profile (Oct-4), neuronal (Nestin) and mesenchymal (CD73, CD105 and Vimentin) genes. Functionally, VNO-derived cells differentiate in vitro into adipocytes, osteocytes and chondrocytes, and presented no tumorigenic potential when injected to Balb/c nu/nu mice. In conclusion, the rabbit VNO-derived cells have a profile that could be supportive to VNO olfactory/neuroreceptor epithelium by delivering factors to epithelial turnover or even by differentiation into epithelial cells to replacement of commissural epithelium.
RESUMEN: El órgano vomeronasal (OVN) es un órgano accesorio de la vía olfatoria, que detecta feromonas y emite señales que afectan la modulación del comportamiento social y reproductivo. Las células madre OVN reemplazan las neuronas durante toda la vida. El objetivo de este estudio fue aislar y caracterizar células derivadas del órgano vomeronasal de conejos raza Nueva Zelanda. Para el aislamiento y el cultivo celular se utilizaron cinco conejos machos con una edad de 120 días. Las células del OVN presentaron etiquetado para la proliferación (PCNA), un perfil indiferenciado (Nanog), neuronal (GFAP), células madre mesenquimales (CD73, CD90 y CD105 y Stro-1). Además, se ob- servó presencia de citoesqueleto (Vimentina, β-tubulina y CK-18) y ausencia de marcadores hematopoyéticos (CD34, CD117 y CD45) tanto por inmunofluorescencia como por citometría de flujo. Me- diante PCR fue posible verificar la expresión de algunos genes de perfil indiferenciado (Oct-4), neuronal (Nestin) y mesenquimatoso (CD73, CD105 y Vimentin). Las células derivadas del OVN se diferencian in vitro en adipocitos, osteocitos y condrocitos, y no presentan un potencial tumorigénico al ser infiltrados en ratones Balb / c nu / nu. En conclusión, las células derivadas de OVN de conejo tienen un perfil que podría ser compatible con el epitelio olfatorio / neurorreceptor de OVN transmitiendo factores al recambio epitelial o incluso mediante la diferenciación en células epiteliales para reemplazar el epitelio comisural.
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Animales , Conejos/anatomía & histología , Órgano Vomeronasal/citología , Células Madre Mesenquimatosas/fisiología , Bulbo Olfatorio/citología , Células Madre/fisiología , Mucosa Olfatoria/citología , Reacción en Cadena de la Polimerasa , Técnica del Anticuerpo Fluorescente , Citometría de Flujo , Neuronas/fisiologíaRESUMEN
Estuaries on wave-dominated coasts generally comprise three sedimentary environments: fluvial sands and gravels derived from the catchment; marine sands characteristic of the beaches and nearshore; and silts and clays that accumulate in the sheltered central basin. Estuarine transition to deltaic form occurs when geomorphological maturity is achieved during coastal evolution. Sedimentary plains become infilled and a narrow channel connects the catchment and facilitates the transport of fluvial sediments to the coast. Here, we present modern sedimentary data that supports the idea that the wave-dominated Shoalhaven system in southeastern Australia has transitioned from an estuary to delta, transporting fluvial sediments to the modern adjacent beach and contributing to coastal progradation. A total of 141 bed channel and swash zone samples were collected from the estuarine channel of the Shoalhaven River and the adjacent Comerong Island and Seven Mile Beach, respectively. Surficial sediments were subject to grain size analysis, whereas random quartz grains from selected samples were used to indicate a qualitative degree of weathering using a scan electron microscopy (SEM). Additionally, selected samples were examined for mineralogical composition using x-ray diffraction (XRD) to provide understanding of sediment transport and provenance. The dataset, one of the most comprehensive modern sedimentary coastal records in Australia, can be used to understand the sediment dynamics and support a diverse range of coastal management decisions. The experiment design and analyses also serve as a model that can be replicated elsewhere to better understand fluvial delivery of sediments to the coast. The dataset and analyses presented here support the research article entitled "Evolution from estuary to delta: alluvial plain morphology and sedimentary characteristics of the Shoalhaven River mouth, southeastern Australia" [1], to which readers should refer to for interpretation.
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Plant growth and arbuscular mycorrhizal colonization were studied in sugarcane, corn and soybean by applying five plant growth promoting fungi: Beauveria bassiana, Metarhizium anisopliae, Pochonia chlamydosporia, Purpureocillium lilacinum, and Trichoderma asperella. Sugarcane, corn and soybean were grown in pots under two treatments: (1) inoculation with the fungal consortium and (2) control without inoculation. In the inoculated treatment, fungal spore suspension were applied to the seeds and shoots were sprayed every 28 days. Means were analyzed by analysis of variance and Tukey's test at 5% probability level. The experiment was arranged in a completely randomized design, with six replications. Fungi consortium mediate root growth in soybean and corn, and arbuscular mycorrhizal colonization in soybean and sugarcane. These findings are probably caused by the fungi producing phytohormones and inducing the plants to synthesize phytohormones: auxins for root growth; and jasmonic, abscisic, and salicylic acids with a role in the regulation of mycorrhizal colonization. These effects are important when seeking conservation strategies in agriculture and livestock production, since Fungi consortium can better mediate soil resource acquisition, promoting greater absorption of nutrients and water.
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Glycine max/crecimiento & desarrollo , Micorrizas/fisiología , Raíces de Plantas/crecimiento & desarrollo , Saccharum/crecimiento & desarrollo , Zea mays/crecimiento & desarrollo , Raíces de Plantas/microbiología , Saccharum/microbiología , Glycine max/microbiología , Simbiosis , Zea mays/microbiologíaRESUMEN
OBJECTIVE: Visual assessment of the EEG still outperforms current computer algorithms in detecting epileptiform discharges. Deep learning is a promising novel approach, being able to learn from large datasets. Here, we show pilot results of detecting epileptiform discharges using deep neural networks. METHODS: We selected 50 EEGs from focal epilepsy patients. All epileptiform discharges (nâ¯=â¯1815) were annotated by an experienced neurophysiologist and extracted as 2â¯s epochs. In addition, 50 normal EEGs were divided into 2â¯s epochs. All epochs were divided into a training (nâ¯=â¯41,381) and test (nâ¯=â¯8775) set. We implemented several combinations of convolutional and recurrent neural networks, providing the probability for the presence of epileptiform discharges. The network with the largest area under the ROC curve (AUC) in the test set was validated on seven independent EEGs with focal epileptiform discharges and twelve normal EEGs. RESULTS: The final network had an AUC of 0.94 for the test set. Validation allowed detection of epileptiform discharges with 47.4% sensitivity and 98.0% specificity (FPR: 0.6/min). For the normal EEGs in the validation set, the specificity was 99.9% (FPR: 0.03/min). CONCLUSIONS: Deep neural networks can accurately detect epileptiform discharges from scalp EEG recordings. SIGNIFICANCE: Deep learning may result in a fundamental shift in clinical EEG analysis.
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Aprendizaje Profundo , Electroencefalografía/métodos , Epilepsia/fisiopatología , Electroencefalografía/normas , HumanosRESUMEN
O objetivo do presente trabalho foi analisar histológica e histo- químicamente a pele do jurará (Kinosternon scorpioides scorpioides). Foram utilizados seis animais (três machos e três fêmeas). Os animais foram eutanasiados com dose letal de tiopental sódico a 2,5%, para colheita de fragmentos de pele mole das patas e pescoço do animal, que após a fixação em líquido de Bouin, foram incluídos em parafina e corados pelas técnicas de hematoxilina-eosina, Giemsa, Sirius red, Reticulina de Gomori e Fucsina-resorcina de Weigert. Os resultados revelaram que a pele do jurará é delgada e composta de epiderme e derme. A epiderme é formada por estrato germinativo constituído por uma única camada de células cilíndricas; estrato espinhoso apresentando duas ou três camadas de células poliédricas; o estrato granuloso não foi observado nos exemplares estudados O estrato córneo apresenta uma delgada camada de queratina mole. Na derme, os fibroblastos foram as células mais freqüentes e as fibras colágenas formavam feixes espessos dispostos em várias direções. No método do Picro Sirius Red sob luz polarizada observou-se que, independente da região analisada, há predomínio de fibras colágenas tipo I em relação ao colágeno tipo III. Foi também observados mastócitos em pequena quantidade e fibras elásticas na região subepidérmica. Concluiu-se que a pele de Kinosternon scorpioides scorpioides possui características semelhantes a dos demais vertebrados (anfíbios, aves e mamíferos), apresenta peculiaridades, como por exemplo, a ausência de papilas dérmicas e glândulas...
The aim of this paper was to study the histology and histochemistry of the skin of six specimens of muçuã (three males and three females). The animals were euthanized through a lethal dose of sodium thiopental at 2.5%. Fragments of the soft skin were fixed in Bouin's solution and processed for inclusion in paraffin. The sections were stained with hematoxylin-eosin, Giemsa, Sirius red, Gomori's reticulin and Weigert's fuchsin-resorcin. The results revealed that the skin is thin and constituted by epidermis and dermis. The epidermis is made up by one layer of cylindrical cells of stratum germinativum, two or three layers of poliedric cells of stratum spinosum, but without stratum granular. The stratum corneum consists of a thin layer of soft keratin. In the dermis, the fibroblasts were the most frequent cells and collagen fibers formed a thick bound displayed in several directions. The Sirius red under polarized light showed that type I collagen was predominant when compared with the occurrence of type III collagen. Mast cells were also found, and elastic fibers were seen in the subepidermic layer. We concluded that the skin of Kinosternon scorpioides scorpioides has histological features similar to other vertebrates (amphibia, aves, mammalia), however without dermal papillae and glands...
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Animales , Masculino , Femenino , Fenómenos Químicos , Miembro Anterior , Miembro Posterior , Cuello , Piel/anatomía & histología , Tortugas/anatomía & histología , Colágeno , Tejido ElásticoRESUMEN
Since the horse has a highly precocial reproductive strategy, most organs are functionally well developed at birth and thus, embryonic and fetal life is interesting. Data on the development of important organs are very limited. Here, we detailed macroscopically and histologically the equine digestive system, focusing on the first third of gestation. At 21 days, the oral cavity was an empty space, and the liver contained proliferating endodermal cells. At 25 days, a fusiform stomach and the pancreatic bud were present. At 28 days, a small tongue and the esophagus occurred. At 30 days, primary and secondary palates were developed, the liver contained cords of hepatocytes, and the pancreas was triangular. At 40 days, crypts had formed in the intestinal loops, cell differentiation was observed in the hepatic parenchyma, and the pancreas was elongated. Pancreatic acini and islets were observed in fetuses of 50 days and intestines were highly convoluted. Three segments of the pharynx were distinguishable at 75 days. At 105 days, the intestinal villi were wide with round tips; especially, the liver, stomach, and oral cavity showed key steps of anatomical and cellular differentiation in early fetuses, whereas other areas, such as pancreas or pharynx were still immature in the investigated phase. Pluripotency analysis using Oct4 showed initial intense staining in all of the digestive system tissues and a later decreased becoming restricted to specific cell layers. In conclusion, our data may contribute to perform a chronological reference of developmental events for approaches predicting pregnancy disorders in horses.
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Sistema Digestivo/embriología , Caballos/embriología , Organogénesis , Animales , Desarrollo Embrionario , Desarrollo FetalRESUMEN
The poultry industry is a sector of agribusiness which represents an important role in the country's agricultural exports. Therefore, the study about embryogenesis of the domestic chicken (Gallus gallus domesticus) has a great economic importance. The aim of this study was to evaluate embryonic development of the endoderm in chicken (Gallus gallus domesticus). Forty fertilized eggs of domestic chickens, starting from the 1st day of gestation and so on until the 19 days of the incubation were collected from the Granja São José (Amparo, SP, Brazil). Embryos and fetus were fixed in 10% formaldehyde solution, identified, weighed, measured, and subjected to light and scanning electron microscopy. The endoderm originates the internal lining epithelium of the digestive, immune, respiratory systems, and the organs can be visualized from the second day (48 h) when the liver is formed. The formation of the digestive system was complete in the 12th day. Respiratory system organs begin at the fourth day as a disorganized tissue and undifferentiated. Their complete differentiation was observed at the 10 days of incubation, however, until the 19 days the syrinx was not observed. The formation of immune system at 10th day was observed with observation of the spleen, thymus, and cloacal bursa. The study of the organogenesis of the chicken based on germ layers is very complex and underexplored, and the study of chicken embryology is very important due the economic importance and growth of the use of this animal model studies such as genetic studies.
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Embrión de Pollo/embriología , Desarrollo Embrionario , Endodermo/embriología , Animales , Embrión de Pollo/anatomía & histología , Embrión de Pollo/ultraestructura , Pollos/anatomía & histología , Pollos/crecimiento & desarrollo , Endodermo/anatomía & histología , Endodermo/ultraestructura , Hígado/anatomía & histología , Hígado/embriología , Hígado/ultraestructura , Microscopía Electrónica de Rastreo , Bazo/anatomía & histología , Bazo/embriología , Bazo/ultraestructuraRESUMEN
The rhea (Rhea americana americana) is an american bird belonging to Ratite's family. Studies related to its morphology are still scarce. This study aims to describe the macroscopic structures of the oropharyngeal cavity. Five heads (2 to 6 months old) formalin preserved were anatomically dissected to expose the oropharynx. The oropharynx of the rhea was "bell-shaped" composed by the maxillary and mandibular rhamphotheca. The roof and floor presented two distinct regions different in colour of the mucosa. The rostral region was pale pink contrasting to grey coloured caudal region. The median longitudinal ridge extended rostrally from the apex of the choana to the tip of the beak in the roof and it is clearly more prominent and rigid than the homolog in the floor that appeared thin and stretched merely along the rostral portion of the regio interramalis. The floor was formed by the interramal region, (regio interramalis) tongue and laryngeal mound containing glove-shaped glottis. This study confirmed the basic morphology of the oropharinx of the rhea. However, important morphological information not previously described is highlighted and contradictory information present in the literature is clarified.(AU)
A ema é uma ave Americana pertencente à familia das Ratitas. Estudos relacionados a sua morfologia são escassos. O objetivo deste estudo foi descrever as estruturas macroscópicas da cavidade orofaríngea. Cinco cabeças (dois a seis meses de idade) de emas fixadas em formol foram dissecadas para a exposição da orofaringe. A orofaringe das emas apresentou formato de "sino" composta pela ranfoteca maxilar e mandibular. O teto e o assoalho apresentavam duas regiões distintas com diferenças na coloração da mucosa. A região rostral era rosa clara contrastando com a coloração cinza da região caudal. A linha longitudinal mediana se estendia rostralmente do ápice da coana ate a extremidade do bico no teto e esta era bem proeminente e rígida quanto a mesma estrutura no assoalho, esta apresentou-se estendida ao longo da porção rostral da região interramal. O assoalho estava formado pela região interramal, língua, glote e cartilagens da laringe com formato de dedos de luvas. O estudo confirma a morfologia básica da orofaringe das emas. Entretanto, importantes informações morfológicas não descritas anteriormente são destacadas e informações contraditórias presentes na literatura são esclarecidas.(AU)
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Animales , Orofaringe/microbiología , Reiformes/anatomía & histología , Reiformes/anomalíasRESUMEN
The aim of this study was to describe the topography of the spinal cord of the red-footed tortoise to establish a morphological basis for applied research in anesthesiology and morphology. Six tortoises from the state of Maranhão (Brazil) that had died of natural causes were used. The common carotid artery was used to perfuse the arterial system with saline solution (heated to 37ºC) and to fix the material with a 20 percent formaldehyde solution. The specimens were then placed in a modified decalcifying solution for 72 hours to allow dorsal opening of the carapace with a chisel and an orthopedic hammer. Dissection of the dorsal musculature and sectioning of the vertebral arches were performed to access the spinal cord. The results revealed the spinal cord of G. carbonaria to be an elongated, whitish mass that reached the articulation between the penultimate and last caudal vertebrae. The cervical intumescence (Intumescentia cervicalis) was located between vertebral segments C5 and T1, whereas the lumbosacral intumescence (Intumescentia lumbalis) was located between T6 and Ca1.
Objetivou-se com este estudo descrever a topografia da medula espinhal do jabuti de "patas vermelhas" no intuito de estabelecer bases morfológicas para a investigação aplicada em morfologia, anestesiologia e cirurgia animal. Foram utilizados seis animais adultos, provenientes do Estado de Maranhão (Brasil), os quais haviam ido a óbito por causas naturais. A artéria carótida comum foi canulada e utilizada para perfusão do sistema arterial com solução salina (aquecida a 37ºC) e para fixação do material com uma solução de formol a 20 por cento. Os animais foram então colocados em uma solução descalcificadora modificada por 72 horas, o que facilitou a abertura dorsal da carapaça com um cizel e um martelo ortopédico. Em seguida, foi realizada a dissecação da musculatura dorsal e secção dos arcos vertebrais para acesso a medula espinal. Os resultados revelaram a medula espinhal de Geochelone carbonaria como uma massa alongada, esbranquiçada, que se estende até a articulação entre penúltima e última vértebra caudal. A intumescência cervical (Intumescentia cervicalis) foi localizada entre os segmentos vertebrais de C5 e T1, enquanto que a intumescência lombossacral (Intumescentia lumbalis) foi localizada entre os segmentos vertebrais de T6 e Ca1.