979 resultados para Fishes, Poisonous
Resumo:
Dissertation presented to obtain the Ph.D. degree in Biology at the Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa.
Resumo:
This paper presents the development of a fish-like robot called Bro-Fish. Bro-Fish aims to be an educational toy dedicated to teaching mechanics, programming and the physics of floating objects to youngsters. The underlying intention is to awaken the interest of children for technology, especially biomimetic (biologically inspired) approaches, in order to promote sustainability and raise the level of ecological awareness. The main focus of this project was to create a robot with carangiform locomotion and controllable swimming, providing the opportunity to customize parts and experiment with the physics of floating objects. Therefore, the locomotion principles of fishes and mechanisms developed in related projects were analysed. Inspired by this background knowledge, a prototype was designed and implemented. The main achievement is the new tail mechanism that propels the robot. The tail resembles the undulation motion of fish bodies and is actuated in an innovative way, triggered by an elegant movement of a rotating helicoidal. First experimental tests revealed the potential of the proposed methodology to effectively generate forward propulsion.
Resumo:
This paper presents the development of a fish-like robot called Bro-Fish. Bro-Fish aims to be an educational toy dedicated to teaching mechanics, programming and the physics of floating objects to youngsters. The underlying intention is to awaken the interest of children for technology, especially biomimetic (biologically inspired) approaches, in order to promote sustainability and raise the level of ecological awareness. The main focus of this project was to create a robot with carangiform locomotion and controllable swimming, providing the opportunity to customize parts and experiment with the physics of floating objects. Therefore, the locomotion principles of fishes and mechanisms developed in related projects were analysed. Inspired by this background knowledge, a prototype was designed and implemented. The main achievement is the new tail mechanism that propels the robot. The tail resembles the undulation motion of fish bodies and is actuated in an innovative way, triggered by an elegant movement of a rotating helicoidal. First experimental tests revealed the potential of the proposed methodology to effectively generate forward propulsion.
Resumo:
Fishes of family Batrachoididae are responsible for great number of injuries in fishermen in North and Northeast regions of Brazil. The genus Thalassophryne presents various venomous species of fishes found in the Brazilian coast, T. nattereri being the most common of them. The venom is ejected through two hollow spines on the dorsal fin and two on pre-opercular regions, which present a venomous gland in the base and can be erected or depressed by the fish. The manifestations of the envenoming were intense local pain, edema and erythema in 43 patients observed in Salinópolis (Pará State) and Aracaju (Sergipe State). There were no systemic manifestations, but necrosis was detected in eight and bacterial infection in ten injured fishermen. The circumstances of the contacts and therapeutic aspects are discussed. Envenoming by the genus Thalassophryne is important and frequent and should be considered of moderate severity grade, since there are not the excruciating pain or the massive local necrosis provoked by scorpionfishes (Scorpaena) or stingrays injuries nor the systemic manifestations that are the most important marker of severe envenoming.
Resumo:
Injuries caused by venomous and poisonous aquatic animals may provoke important morbidity in humans. The phylum Echinoderma include more than 6000 species of starfish, sea urchins, sand dollars, and sea cucumbers some of which have been found responsible for injuries to humans. Initial injuries by sea urchins are associated with trauma and envenomation, but later effects can be observed. Sea urchin granuloma is a chronic granulomatous skin disease caused by frequent and successive penetration of sea urchin spines which have not been removed from wounds. The authors report a typical case of sea urchin granuloma in a fisherman and its therapeutic implications.
Resumo:
The authors report neuromuscular manifestations in a 45-year-old woman after consuming octopus meat (Octopus sp.). The patient presented malaise, paresthesias in perioral and extremity areas, intense muscular weakness and arterial hypotension, followed by severe itch and disseminated cutaneous rash. Gastrointestinal manifestations and fever were not observed, reducing the probability of alimentary poisoning. The presence of muscular and neurological symptoms suggests neurotoxin action, which could have been ingested by the victim from the octopus salivary glands or from an accumulation of toxins in the meat, or by an unknown mechanism. There is little known about toxins of the Octopus genus and this communication is important alert to the possibility of poisoning in humans that eat octopus and its differentiation from alimentary poisonings arising from incorrect conservation of seafood.
Resumo:
Puffer fish can be poisonous due to the presence of the potent neurotoxins such as Tetrodotoxin (TTX) and Saxitoxin (STX) found in its tissues. The authors report 27 human poisonings from ingestion of puffer fish in patients treated at Toxicology Centers in the states of Santa Catarina and Bahia, Brazil, between 1984 and January 2009. Poisonings were classified as moderate (52%) and severe (33%), two deaths were observed. Early diagnosis is very important to ensure respiratory support.
Resumo:
Pleurolophocercous cercariae emerged from naturally infected Melanoides tuberculata from Minas Gerais State, Brazil, were used to perform experimental infection of laboratory-reared Poecilia reticulata. Mature metacercariae were obtained from the gills of fishes and force-fed to Mus musculus. The adult parasites which recovered from small intestines of mice were identified as Centrocestus formosanus. This is the first report of M. tuberculata as intermediate host of this heterophyid in Brazil.
Resumo:
The present paper reports two cases of human envenoming by colubrid snakes of Philodryas, considered as not poisonous, showing evidence of the clinical aspects and the evolution of the symptoms of envenoming. The similarity of these cases with those caused by Bothrops suggests a more careful evaluation on the victims considering the medical treatment to be adopted.
Resumo:
INTRODUCTION: The fishes of continental Brazil have socioeconomic importance due to their potential for sport fishing and commercial and subsistence uses, as seen in the Upper Paraguay River Basin, particularly in the municipalities of the Pantanal region, where it is the second largest economic activity. Injuries caused in professional fishermen are common and poorly studied, as in other regions of the country. METHODS: Data were obtained from questionnaires and interviews with 100 professional fishermen, 50 in each municipality, between December 2008 and October 2009. RESULTS: All the fishermen reported some kind of injury caused by fish stings (78% of injuries) and fish, alligator and snake bites (22%) on the hands (46% of cases) and feet (35% of cases). Most of the patients had mild symptoms. The most severe cases were associated with secondary bacterial infections and required specific treatment and prolonged recovery associated with social and economic losses. CONCLUSIONS: The results of this study indicate that the stressful work conditions, inattention to basic preventive measures and carelessness were factors that contributed to accidents and that the toxicity and ability to inflict mechanical trauma of some aquatic species, plus the ineffective use of first aid and hospital treatment, contributed to the high morbidity and complications in many cases. Data from this study are relevant to the fishing communities of the Pantanal region, since they reveal high rates of accidents, lack of knowledge concerning first aid, initial treatment, injury prevention and lack of medical follow-up of the population.
Resumo:
Venomous animals are those that, by means of a hunting and defense mechanism, are able to inject their prey with a toxic substance produced in their bodies, directly from specialized glands (e.g., tooth, sting, spur) through which the poison passes. Millipedes are poisonous animals; they can be harmful to humans, and their effects usually manifest as erythematous, purpuric, and cyanotic lesions; local pain; and paresthesia. Here, we report a case of skin contact with a millipede for 6h resulting in skin lesions similar to blue toe syndrome.
Resumo:
AbstractINTRODUCTION:We present a review of injuries in humans caused by aquatic animals in Brazil using the Information System for Notifiable Diseases [ Sistema de Informação de Agravos de Notificação (SINAN)] database.METHODS:A descriptive and retrospective epidemiological study was conducted from 2007 to 2013.RESULTS:A total of 4,118 accidents were recorded. Of these accidents, 88.7% (3,651) were caused by venomous species, and 11.3% (467) were caused by poisonous, traumatic or unidentified aquatic animals. Most of the events were injuries by stingrays (69%) and jellyfish (13.1%). The North region was responsible for the majority of reports (66.2%), with a significant emphasis on accidents caused by freshwater stingrays (92.2% or 2,317 cases). In the South region, the region with the second highest number of records (15.7%), jellyfish caused the majority of accidents (83.7% or 452 cases). The Northeastern region, with 12.5% of the records, was notable because almost all accidents were caused by toadfish (95.6% or 174 cases).CONCLUSIONS:Although a comparison of different databases has not been performed, the data presented in this study, compared to local and regional surveys, raises the hypothesis of underreporting of accidents. As the SINAN is the official system for the notification of accidents by venomous animals in Brazil, it is imperative that its operation be reviewed and improved, given that effective measures to prevent accidents by venomous animals depend on a reliable database and the ability to accurately report the true conditions.
Resumo:
Ethnobiology includes the study of how populations perceive and classify organisms. This study focuses on the utilization and classification of fishes by fishermen from the Tocantins river. The study area is located between the cities of Imperatriz and Estreito (Maranhão and Tocantins States). Interviews with fishermen and collection of fish species were performed from October 1987 to June 1988. The criteria used by fishermen to classify fish species are mainly morphological, such as related to body shape and coloration. Fish habitat is also an information used in folk classification. Terrestrial plants and animals are a reference for some fish names. Fishermen showed a deeper knowledge and detailed classification of species of fish used for food, sale, or medicine. Folk classification represents the knowledge a population has on its environment, and it is more detailed on species which are part of its realized niche as indicated by this study.
Resumo:
Anphira branchialisgen. et sp. nov. (Crustacea, Isopoda, Cymothoidae) is described from the dorsal areas of the gill chambers of three species of piranhas (Serrasalmusspp.). The fishes were caught in rivers near Manaus, Amazonas State and on Maracá island, Federal Territory of Roraima, Brasil. The new genus and species is characterized by having large, flat coxal plates on ail 7 pereonites. These plates usually extend beyond the margins of the following segments and the 7th ones extend nearly to the pleotelson and cover the lateral margins of the pleonites. The mandible of this species is rounded, "foot shaped" and without incisor. The mandibular palp is short and stout. The maxillules have 3 terminal and 2 subterminal spines. The pleopods are simple lamellar structures with rounded tips. Evidence is presented that these parasites feed on gill filaments.
Resumo:
Our study provides paleontological and geological data substantiating a paleoenvironmental model for the upper Miocene-Pliocene of Southwestern Amazonia. The extensive Late Tertiary sediments of The Solimões Formation, outcropping in Southwestern Amazonia, were deposited by a complex megafan system, originating in the high Peruvian Andes. The megafan system was the sedimentological response to the Andean Quechua tectonic phase of Tertiary age, producing sediments that fdled the foreland basin of Southwestern Amazonia. Occurrences of varied vertebrate fossil assemblages of the Huayquerian-Montehermosan Mammal age collected in these sediments support this interpretation. The fauna includes several genera and species of fishes, reptiles, birds, mammals and appears to be one that could have lived in or near a riverine habitat. In the Late Pliocene, the megafan system became inactive as a result of the influence of the Diaguita Tectonical Phase.