Consulta: subjectFacets:"Toxins"
Registros recuperados: 33
Data/hora: 06/06/2024 08:39:42

Un nouvel outil dans l'identification et la quantification des dinophysistoxines (DTXs) : le couplage Chromatographie Liquide Haute Performance / Spectrométrie de masse par piégeage d'ions quadripôlaire et interface d'électro- nébulisation (CLHP/SM2)
Provedor de dados: 5
Autores: Mondeguer, Florence.
This report presents a new method for detection and confirmed quantification of dinophysistoxins (DTXs) using high-performance liquid chromatography coupled to mass spectrometry with an ion trap and électrospray interface (HPLC/ESI/MS2).  The parameters of the ESI source and ion trap spectrum analyser were optimised to provide detection of DTXs with maximum sensitivity. These improvements were obtained after reverse-phase separation on a C18 column, with a first elution to 0.1% TFA (75:25, v/v) in isocratic acetonitrile/water mode without flow split at a column flow rate of 200 µl/min for 15 min. A second elution gradient step was added to allow optimised processing of long series of analyses without signal obstruction. This method was validated...
Tipo: Text
Palavras-chave: Intoxication par les coquillages; Dinophysistoxines; Acide okadaïque; Dinophysistoxine-1; Couplage CLHP-électronébulisation- SM2 par piège d'ions; Toxines.; Shellfish poisoning; Dinophysistoxines; Okadaïque Acid; Dinophysistoxine-1; Liquid Chromatography coupled Ion Trap; Toxins.
Ano: 2002
URL: http://archimer.ifremer.fr/doc/00136/24763/22839.pdf

Exposure to the Neurotoxic Dinoflagellate, Alexandrium catenella, Induces Apoptosis of the Hemocytes of the Oyster, Crassostrea gigas
Provedor de dados: 5
Autores: Medhioub, Walid; Ramondenc, Simon; Vanhove, Audrey; Vergnes, Agnes; Masseret, Estelle; Savar, Veronique; Amzil, Zouher; Laabir, Mohamed; Rolland, Jean-luc.
This study assessed the apoptotic process occurring in the hemocytes of the Pacific oyster, Crassostrea gigas, exposed to Alexandrium catenella, a paralytic shellfish toxins (PSTs) producer. Oysters were experimentally exposed during 48 h to the toxic algae. PSTs accumulation, the expression of 12 key apoptotic-related genes, as well as the variation of the number of hemocytes in apoptosis was measured at time intervals during the experiment. Results show a significant increase of the number of hemocytes in apoptosis after 29 h of exposure. Two pro-apoptotic genes (Bax and Bax-like) implicated in the mitochondrial pathway were significantly upregulated at 21 h followed by the overexpression of two caspase executor genes (caspase-3 and caspase-7) at 29 h,...
Tipo: Text
Palavras-chave: Shellfish; Toxins; Apoptosis; Gene expression.
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00176/28744/27213.pdf

Effects of copper and butyltin compounds on the growth, photosynthetic activity and toxin production of two HAB dinoflagellates : the planktonic Alexandrium catenella and the benthic Ostreopsis cf. ovata
Provedor de dados: 5
Autores: Couet, Douglas; Pringault, Olivier; Bancon-montigny, Chrystelle; Briant, Nicolas; Poulichet, Francoise Elbaz; Delpoux, Sophie; Yahia, Ons Kefi-daly; Hela, Bengharbia; Charaf, M'Rabet; Herve, Fabienne; Rovillon, Georges-augustin; Amzil, Zouher; Laabir, Mohamed.
Controlled laboratory experiments were conducted to test the effects of copper (Cu2+) and butyltins (BuT) on the growth, photosynthetic activity and toxin content of two HABs (Harmful Algal Blooms) dinoflagellates, the planktonic Alexandrium catenella and the benthic Ostreopsis cf. ovata. Microalgae were exposed to increasing concentrations of Cu2+ (10−4 to 31 nM) or BuT (0.084 to 84 nM) for seven days. When considering the growth, EC50 values were 0.16 (±0.09) nM and 0.03 (±0.02) nM of Cu2+ for A. catenella and O. cf. ovata, respectively. Regarding BuT, EC50 was 14.2 (±6) nM for O. cf. ovata, while A. catenella growth inhibition appeared at BuT concentrations ≥27 nM. Photosynthetic activity of the studied dinoflagellates decreased with increasing Cu and...
Tipo: Text
Palavras-chave: Alexandrium catenella; Ostreopsis cf. ovata; Cu; Butyltin; Photosynthesis; Toxins.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00418/52970/53896.pdf

Ostreopsis lenticularis Y. Fukuyo (Dinophyceae, Gonyaulacales) from French Polynesia (South Pacific Ocean): A revisit of its morphology, molecular phylogeny and toxicity
Provedor de dados: 5
Autores: Chomérat, Nicolas; Bilien, Gwenael; Derrien, Amelie; Henry, Kévin; Ung, André; Viallon, Jérôme; Darius, Hélène Taiana; Mahana Iti Gatti, Clémence; Roué, Mélanie; Hervé, Fabienne; Réveillon, Damien; Amzil, Zouher; Chinain, Mireille.
To date, the genus Ostreopsis comprises eleven described species, of which seven are toxigenic and produce various compounds presenting a major threat to human and environmental health. The taxonomy of several of these species however remains controversial, as it was based mostly on morphological descriptions leading, in some cases, to ambiguous interpretations and even possible misidentifications. The species Ostreopsis lenticularis was first described by Y. Fukuyo from French Polynesia using light microscopy observations, but without genetic information associated. The present study aims at revisiting the morphology, molecular phylogeny and toxicity of O. lenticularis based on the analysis of 47 strains isolated from 4 distinct locales of French...
Tipo: Text
Palavras-chave: ITS-5.8S rDNA; LSU rDNA; Microscopy; Ostreopsis lenticularis; Taxonomy; Toxins.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00486/59747/62887.pdf

Interaction between Insects, Toxins, and Bacteria: Have We Been Wrong So Far?
Provedor de dados: 5
Autores: Tetreau, Guillaume.
Toxins are a major virulence factor produced by many pathogenic bacteria. In vertebrates, the response of hosts to the bacteria is inseparable from the response to the toxins, allowing a comprehensive understanding of this tripartite host-pathogen-toxin interaction. However, in invertebrates, this interaction has been investigated by two complementary but historically distinct fields of research: toxinology and immunology. In this article, I highlight how such dichotomy between these two fields led to a biased, or even erroneous view of the ecology and evolution of the interaction between insects, toxins, and bacteria. I focus on the reason behind such a dichotomy, on how to bridge the fields together, and on confounding effects that could bias the outcome...
Tipo: Text
Palavras-chave: Invertebrate immunity; Host-pathogens interaction; Toxins; Bacillus thuringiensis; Resistance.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00457/56834/78950.pdf

The Complete Genome Sequence of the Fish Pathogen Tenacibaculum maritimum Provides Insights into Virulence Mechanisms
Provedor de dados: 5
Autores: Perez-pascual, David; Lunazzi, Aurelie; Magdelenat, Ghislaine; Rouy, Zoe; Roulet, Alain; Lopez-roques, Celine; Larocque, Robert; Barbeyron, Tristan; Gobet, Angelique; Michel, Gurvan; Bernardet, Jean-francois; Duchaud, Eric.
Tenacibaculum maritimum is a devastating bacterial pathogen of wild and farmed marine fish with a broad host range and a worldwide distribution. We report here the complete genome sequence of the T. maritimum type strain NCIMB 2154(T). The genome consists of a 3,435,971-base pair circular chromosome with 2,866 predicted protein-coding genes. Genes encoding the biosynthesis of exopolysaccharides, the type IX secretion system, iron uptake systems, adhesins, hemolysins, proteases, and glycoside hydrolases were identified. They are likely involved in the virulence process including immune escape, invasion, colonization, destruction of host tissues, and nutrient scavenging. Among the predicted virulence factors, type IX secretion-mediated and cell-surface...
Tipo: Text
Palavras-chave: Tenacibaculum maritimum; Fish pathogen; Virulence factors; Genome; Toxins.
Ano: 2017
URL: https://archimer.ifremer.fr/doc/00488/59939/63150.pdf

Validation d’un procédé automatisé d’extraction sur phase solide de glandes digestives de moules pour l’identification et la quantification des dinophysistoxines en LC/ESI/SM2 par piégeage d’ions quadripolaire
Provedor de dados: 5
Autores: Mondeguer, Florence; Mestres, Gilberte; Rouland, Caroline; Montagu, Monique; Maillols, Hélène.
This report presents a new extraction method of the dinophysistoxins (DTXs), confirmed by quantification using high-performance liquid chromatography coupled to mass spectrometry with an ion trap and electro spray interface (HPLC/ESI/MS2). The method originality consists on the adaptation of DTXs basic extraction procedure (liquid/ liquid) to a solid phase extraction (SPE) via a robotic station: ASPEC XLi The parameters of the automatization procedure were optimized to obtain the best DTXs recovery rate. These improvements were loaded with digestive gland mussel homogenat realized on a silica cartridge SPE, activated in hexane/chloroform (50:50), washed with hexane/chloroform (50:50) and extracted by an elution gradient (chloroform methanol (65:35) and...
Tipo: Text
Palavras-chave: Toxines; Intoxication des coquillages; Dinophysistoxines; Acide okadaïque; Dinophysistoxine-1; Méthode alternative; Extraction sur phase solide; Automatisation; Couplage CLHP/ESI/SM2 par piège d’ions.; Toxins; Shellfish poisoning; Dinophysistoxins; Okadaic acid; Dinophysistoxin-1; Alternative method; Solid phase extraction; Automation; Liquid chromatography coupled ion trap.
Ano: 2003
URL: http://archimer.ifremer.fr/doc/00342/45270/44724.pdf

In vitro assay of biological and chemical toxins using antibodies against lethal toxin neutralizing factor
Provedor de dados: 79
Autores: LIPPS,B. V.
Lethal Toxin Neutralizing Factor (N-LTNF), MW 63.0 kDa, was isolated from opossum serum. After trypsin digestion, the active domain of N-LTNF was isolated and sequenced. The synthetic peptide consisting of ten amino acids was designated as LT-10. N-LTNF and LT-10 inhibited the lethality of animal, plant and bacteria toxins when tested on mice non-immunologically. The antibodies against N-LTNF and LT-10 only reacted immunologically with toxins and not with non-toxic substances. Anti-LTNF and anti-LT-10 reacted immunologically by ELISA test with toxins that were not detected by mouse test, such as cholera toxin and digoxin. Anti-LTNF and anti-LT-10 failed to react immunologically with non-toxic substances, such as nerve growth factor and collagen. Currently,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Antibodies; In vitro assay; Lethal toxin neutralizing factor; Toxins; Venoms.
Ano: 2002
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0104-79302002000200003

Preliminary molecular characterization of a proinflammatory and nociceptive molecule from the Echinometra lucunter spines extracts
Provedor de dados: 80
Autores: Sciani,Juliana Mozer; Zychar,Bianca; Gonçalves,Luis Roberto; Giorgi,Renata; Nogueira,Thiago; Pimenta,Daniel Carvalho.
Abstract  Background  Sea urchins are animals commonly found on the Brazilian shoreline, being Echinometra lucunter the most abundant species. Accidents caused by E. lucunter have been reported as one of the most frequent in Brazil, and are characterized by intense pain and inflammation, consequence of spine puncture in the skin. In order to characterize such toxic effects, we isolated one molecule that caused inflammatory and nociceptive effects.  Methods E. lucunter specimens were collected without gender distinction. Spines were removed and molecules were extracted, fractionated by RP-HPLC and assayed for inflammatory and nociceptive activity, in a biological-driven fractionation way, until the obtainment of one active molecule and its subsequent...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Toxins; Sea urchin; Echinometra lucunter; Spines; Inflammation.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-91992017000100318

On frogs, toxins and true friendship: an atypical case report
Provedor de dados: 80
Autores: Daniel-Ribeiro,Cláudio Tadeu; Roussilhon,Christian.
Abstract The authors report a series of events including the scientific interest for poisonous dendrobates of French Guiana, the human confrontation with the immensity of the evergreen rainforest, the fragility of the best-prepared individuals to a rough life, and the unique and very special manifestation of a solid friendship between two experts and enthusiasts of outdoor life. In the evergreen forest of South America, as in many other scientific field expeditions, everything may suddenly go wrong, and nothing can prepare researchers to accidents that may occur in a succession of uncontrollable errors once the first mistake is done. This is what happened during an expedition in search for dendrobates by an experienced forest guide and naturalist. The...
Tipo: Info:eu-repo/semantics/report
Palavras-chave: Dart frogs; Dendrobatidae; Toxins; French Guiana.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-91992016000100501

Highlights in the knowledge of brown spider toxins
Provedor de dados: 80
Autores: Chaves-Moreira,Daniele; Senff-Ribeiro,Andrea; Wille,Ana Carolina Martins; Gremski,Luiza Helena; Chaim,Olga Meiri; Veiga,Silvio Sanches.
Abstract Brown spiders are venomous arthropods that use their venom for predation and defense. In humans, bites of these animals provoke injuries including dermonecrosis with gravitational spread of lesions, hematological abnormalities and impaired renal function. The signs and symptoms observed following a brown spider bite are called loxoscelism. Brown spider venom is a complex mixture of toxins enriched in low molecular mass proteins (4–40 kDa). Characterization of the venom confirmed the presence of three highly expressed protein classes: phospholipases D, metalloproteases (astacins) and insecticidal peptides (knottins). Recently, toxins with low levels of expression have also been found in Loxosceles venom, such as serine proteases, protease...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Brown spider; Loxosceles; Venom; Toxins; Loxoscelism; Phospholipase-D; Metalloprotease; Insecticidal peptides; Serineprotease; Hyaluronidase.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-91992017000100201

Professor José Roberto Giglio and toxinnology in Brazil: 48 years in research
Provedor de dados: 80
Autores: Soares,A. M.; Oliveira,C. Z.; Santana,C. D.; Menaldo,D. L.; Silveira,L. B.; Teixeira,S. S.; Rueda,A. Q.; Marcussi,S.
This work succinctly describes the professional and scientific life of Dr. José R. Giglio, one of the most outstanding Brazilian researchers in the field of Toxinology. During his long and successful career, he has made major contributions, especially in elucidating the function, structure, and mechanisms of action of animal venom proteins (from snakes, scorpions and spiders) as well as the characterization of antibodies and several inhibitors of venoms and toxins. We present here a brief history of Dr. Giglio’s personal and professional life, also reporting some of his numerous published scientific articles on venoms from snakes (Bothrops, Crotalus, and other genera), scorpions (Tityus sp), spiders (Phoneutria sp), their isolated toxins and natural...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Toxinology; Animal venoms; Toxins; Inhibitors; Homage; Giglio JR.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-91992007000400003

Purification procedure for the isolation of a P-I metalloprotease and an acidic phospholipase A 2 fromBothrops atrox snake venom
Provedor de dados: 80
Autores: Menaldo,Danilo L.; Jacob-Ferreira,Anna L.; Bernardes,Carolina P.; Cintra,Adélia C. O.; Sampaio,Suely V.
Background Snake venoms are complex mixtures of inorganic and organic components, mainly proteins and peptides. Standardization of methods for isolating bioactive molecules from snake venoms is extremely difficult due to the complex and highly variable composition of venoms, which can be influenced by factors such as age and geographic location of the specimen. Therefore, this study aimed to standardize a simple purification methodology for obtaining a P-I class metalloprotease (MP) and an acidic phospholipase A2 (PLA 2 ) from Bothrops atroxvenom, and biochemically characterize these molecules to enable future functional studies.Methods To obtain the toxins of interest, a method has been standardized using consecutive isolation steps. The purity level of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Snake venoms; Bothrops atrox; Toxins; Metalloprotease; Phospholipase A2; Isolation; Characterization; Chromatography.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-91992015000100337

Crotamine in Crotalus durissus: distribution according to subspecies and geographic origin, in captivity or nature
Provedor de dados: 80
Autores: Tasima,Lídia J.; Serino-Silva,Caroline; Hatakeyama,Daniela M.; Nishiduka,Erika S.; Tashima,Alexandre K.; Sant’Anna,Sávio S.; Grego,Kathleen F.; Morais-Zani,Karen de; Tanaka-Azevedo,Anita M.
Abstract  Background: Crotalus durissus is considered one of the most important species of venomous snakes in Brazil, due to the high mortality of its snakebites. The venom of Crotalus durissus contains four main toxins: crotoxin, convulxin, gyroxin and crotamine. Venoms can vary in their crotamine content, being crotamine-negative or -positive. This heterogeneity is of great importance for producing antivenom, due to their different mechanisms of action. The possibility that antivenom produced by Butantan Institute might have a different immunorecognition capacity between crotamine-negative and crotamine-positive C. durissus venoms instigated us to investigate the differences between these two venom groups.  Methods: The presence of crotamine was analyzed...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Rattlesnake; Snake venom; Toxins; Venom variation; Antivenom.
Ano: 2020
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-91992020000100307

A clinical trial protocol to treat massive Africanized honeybee (Apis mellifera) attack with a new apilic antivenom
Provedor de dados: 80
Autores: Barbosa,Alexandre Naime; Boyer,Leslie; Chippaux,Jean-Philippe; Medolago,Natalia Bronzatto; Caramori,Carlos Antonio; Paixão,Ariane Gomes; Poli,João Paulo Vasconcelos; Mendes,Mônica Bannwart; Santos,Lucilene Delazari dos; Ferreira Jr,Rui Seabra; Barraviera,Benedito.
Abstract  Background  Envenomation caused by multiple stings from Africanized honeybees Apis mellifera constitutes a public health problem in the Americas. In 2015, the Brazilian Ministry of Health reported 13,597 accidents (incidence of seven cases per 100,000 inhabitants) with 39 deaths (lethality of 0.25%). The toxins present in the venom, which include melittin and phospholipase A2, cause lesions in diverse organs and systems that may be fatal. As there has been no specific treatment to date, management has been symptomatic and supportive only.  Methods  In order to evaluate the safety and neutralizing capacity of a new apilic antivenom, as well as to confirm its lowest effective dose, a clinical protocol was developed to be applied in a multicenter,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Apis mellifera; Bee venom; Toxins; Envenomation; Heterologous serum; Apilic antivenom; Bee antivenom.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-91992017000100309

Initial peptidomic profiling of Brazilian sea urchins: Arbacia lixula, Lytechinus variegatus and Echinometra lucunter
Provedor de dados: 80
Autores: Sciani,Juliana Mozer; Emerenciano,Andrews Krupinski; Silva,José Roberto Machado Cunha da; Pimenta,Daniel Carvalho.
Abstract  Background  Sea urchins can be found throughout the Brazilian coast and are reported to be one of the major causes of marine accidents on the shoreline. Although not lethal, these accidents are reported to be extremely painful. In order to understand the toxinology of the Brazilian urchins, a peptidomic approach was performed aiming to characterize the naturally occurring peptides in both the coelomic fluid and the spine.  Methods  Animals were collected without gender distinction and samples of the coelomic fluid and spines extracted were analyzed by RP-HPLC and mass spectrometry for peptide de novo sequencing.  Results  Several peptides were identified either in the coelomic fluid or the spine extract (except for E. lucunter). The peptide...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Peptides; Toxins; Sea urchin; Peptidomics.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-91992016000100313

Enzymatic and toxinological activities of Hypnale hypnale (hump-nosed pit viper) venom and its fractionation by ion exchange high performance liquid chromatography
Provedor de dados: 80
Autores: Tan,CH; Sim,SM; Gnanathasan,CA; Fung,SY; Ponnudurai,G; Pailoor,J; Tan,NH.
Hypnale hypnale (hump-nosed pit viper) has been recently identified as one of the medically important venomous snakes in Sri Lanka and on the southwestern coast of India. The characterization of its venom is essential for understanding the pathophysiology of envenomation and for optimizing its management. In the present study, the biological properties of Hypnale hypnale venom and venom fractions obtained using Resource Q ion exchange chromatography were determined. The venom exhibited toxic activities typical of pit viper venom, comparable to that of its sister taxon, the Malayan pit viper (Calloselasma rhodostoma). Particularly noteworthy were its high activities of thrombin-like enzyme, proteases, phospholipase A2, L-amino acid oxidase and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Hypnale hypnale; Venom; Enzymes; Toxins; Fibrinogen; Nephrotoxicity.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-91992011000400015

Bufotenine is able to block rabies virus infection in BHK-21 cells
Provedor de dados: 80
Autores: Vigerelli,Hugo; Sciani,Juliana Mozer; Jared,Carlos; Antoniazzi,Marta Maria; Caporale,Graciane Maria Medeiros; Silva,Andréa de Cássia Rodrigues da; Pimenta,Daniel C.
Background Rabies is a fatal zoonotic neglected disease that occurs in more than 150 countries, and kills more than 55.000 people every year. It is caused by an enveloped single stranded RNA virus that affects the central nervous system, through an infection initiated by the muscular nicotinic acetylcholine receptor, according to many authors. Alkaloids, such as acetylcholine, are widespread molecules in nature. They are present in numerous biological fluids, including the skin secretion of many amphibians, in which they act (together with proteins, peptides and steroids) as protection agents against predators and/or microorganisms. Among those amphibians that are rich in alkaloids, there is the genus Rhinella.Methods Bufotenine was isolated from Rhinela...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Rabies; Rhinella; Bufotenine; Alkaloids; Toxins; Mass spectrometry.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-91992014000200336

Clostridial toxins: potent poisons, potent medicines
Provedor de dados: 80
Autores: Baldassi,L.
Clostridium is an anaerobic bacterial genus. The clostridia produce more protein toxins than any other bacterial genus and are a rich reservoir of toxins for research and medicinal uses. Clostridia are widely spread in the environment: soil, dust and water, presenting more than 120 described species, although few can cause diseases. Diseases can grossly be divided into neurotropic disorders (nervous system is primarily affected), enterotoxemias (affecting intestinal tract and parenchymatous organs), and gas gangrene (myonecrosis with toxemia). Undoubtedly the most widely recognized infection due to anaerobes was clostridial myonecrosis, but recently interest has arisen for the role of clostridia in intestinal diseases. This report describes the most...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Clostridiosis; Clostridium spp; Toxins.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-91992005000400002

Melittin induces in vitro death of Leishmania (Leishmania) infantum by triggering the cellular innate immune response
Provedor de dados: 80
Autores: Pereira,Andreia Vieira; Barros,Gustavo de; Pinto,Erika Gracielle; Tempone,Andre Gustavo; Orsi,Ricardo de Oliveira; Santos,Lucilene Delazari dos; Calvi,Sueli; Ferreira Jr,Rui Seabra; Pimenta,Daniel Carvalho; Barraviera,Benedito.
Abstract  Background Apis mellifera venom, which has already been recommended as an alternative anti-inflammatory treatment, may be also considered an important source of candidate molecules for biotechnological and biomedical uses, such as the treatment of parasitic diseases.  Methods  Africanized honeybee venom from Apis mellifera was fractionated by RP-C18-HPLC and the obtained melittin was incubated with promastigotes and intracellular amastigotes of Leishmania (L.) infantum. Cytotoxicity to mice peritoneal macrophages was evaluated through mitochondrial oxidative activity. The production of anti- and pro-inflammatory cytokines, NO and H2O2 by macrophages was determined.  Results  Promastigotes and intracellular amastigotes were susceptible to melittin...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Melittin; Apis mellifera; Leishmania; Leishmaniasis; Peptides; Toxins; Antiparasitic; Cytokines.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-91992016000100301

Expressed sequence tags in venomous tissue of Scorpaena plumieri (Scorpaeniformes: Scorpaenidae)
Provedor de dados: 83
Autores: Costa,Fábio L. S.; Lima,Maria E. De; Pimenta,Adriano C.; Figueiredo,Suely G.; Kalapothakis,Evanguedes; Salas,Carlos E.
Species of the family Scorpaenidae are responsible for accidents and sporadic casualties by the shore they inhabit. The species Scorpaena plumierifrom this family populate the Northeastern and Eastern coast of Brazil causing human envenomation characterized by local and systemic symptoms. In experimental animals the venom induces cardiotoxic, hypotensive, and airway respiratory effects. As first step to identify the venom components we isolated gland mRNA to produce a cDNA library from the fish gland. This report describes the partial sequencing of 356 gland transcripts from S. plumieri. BLAST analysis of transcripts showed that 30% were unknown sequences, 17% hypothetical proteins, 17% related to metabolic enzymes, 14% belonged to signal transducing...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: CDNAs; EST; Glands; Lectin; Scorpionfish; Toxins.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252014000400871

Marine Seafood Toxin Diseases: Issues In Epidemiology &amp; Community Outreach
Provedor de dados: 20
Autores: Weisman, R.; Baden, D.G.; Blythe, D.G.; Fleming, L.E.; Bean, J.A.
In addition to increased seafood consumption and tourism, recent studies link global climate change with an apparent increasing incidence of the Marine Seafood Toxin diseases. However, the epidemiology of the human diseases caused by the harmful marine phytoplankton is still in its infancy. In general, the epidemiology of these diseases has consisted of case reports of acute illness, sometimes as epidemic outbreaks, associated with the ingestion of suspicious seafood. Furthermore, even these outbreaks are highly under-reported, especially in poorer countries and in traditionally non-endemic areas. True incidence data are not available due to the lack of disease and exposure biomarkers in humans, as well as the global lack of routine exposure and disease...
Tipo: Report
Palavras-chave: Toxins; Diseases.
Ano: 1998
URL: http://hdl.handle.net/1834/758

Depuration and transformation of PSP toxins in the South African abalone Haliotis midae
Provedor de dados: 20
Autores: Pitcher, G.C.; Roesler, C.S.; Etheridge, S.M.
Abalone were grown: on diets of 1) artificial feed, 2) kelp, their in situ food source, which contained saxitoxin (STX) derivatives, and 3) in filtered seawater without a food source, to investigate the depuration and transformation of toxins under feeding and starving conditions. The abalone were toxic at the start of each treatment (~160 µg STX eq 100 g-1 tissue). They depurated at a rate of 6.27 µg STX eq 100 g-1 tissue d-1 over the 2 week incubation period when fed artificial feed; however, no depuration was observed in starved or kelp-fed animals. Toxin transformations occurred in abalone for each treatment. Toxin derivatives decreased in organisms fed artificial feed, and no B1 was detected during this treatment. Toxin composition was not...
Tipo: Working Paper
Palavras-chave: Toxins.
Ano: 2003
URL: http://hdl.handle.net/1834/376

Summary and Recommendations of the International Workshop on Aflatoxin Contamination of Groundnut
Provedor de dados: 30
Palavras-chave: Mycotoxins; Groundnuts; ELISA; Genotypes; Sampling; Detoxification; Chromatography; Toxins; Fungi; Immunological techniques.
Ano: 1988
URL: http://agropedia.iitk.ac.in/openaccess/?q=node/4056

Dehydration curve, fungi and mycotoxins in Tifton 85 hay dehydrated in the field and in shed
Provedor de dados: 96
Autores: Taffarel,Loreno Egidio; Mesquita,Eduardo Eustáquio; Castagnara,Deise Dalazen; Costa,Patrícia Barcellos; Neres,Marcela Abbado; Horn,Marcelina Bottoni; Oliveira,Paulo Sérgio Rabello de; Meinerz,Cristiane Claudia.
The objective of this study was to estimate the dehydration curve and occurrence of fungi and mycotoxins in Tifton 85 hay. The experimental design was randomized blocks in split plots with four replications and five levels of nitrogen (0, 25, 50, 75 and 100 kg ha-1) in the form of urea, two regrowth ages (28 and 35 days) and drying hay in the sun and in shed. After harvesting, the grass was sampled four times (0, 8, 23 and 32 hours) to dry in the sun and twelve times (0, 3, 18, 27, 42, 51, 66, 75, 90, 99, 114 and 123 hours) for drying in shed, turned over daily. The fungi were identified after seeding and growth in three steps of haymaking (cutting, baling and after 30 days of storage). To verify the presence of mycotoxins, 20 samples, composed of hay...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Contaminants; Dry matter; Forage conservation; Microorganisms; Toxins.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982013000600003

Identificação do gene mcyA em florações naturais de Radiocystis fernandoi, em um tributário do reservatório de Rosana, Brasil - doi: 10.4025/actascibiolsci.v33i3.6802
Provedor de dados: 3
Autores: Fonseca, Iraúza Arroteia; UEM; Maniglia, Thiago Cintra; UEM; Rodrigues, Liliana; UEM; Prioli, Alberto José; UEM; Prioli, Sônia Maria Alves Pinto; UEM.
As cianobactérias são conhecidamente produtoras de toxinas. Dentro de uma mesma espécie, podemos encontrar variedades tóxicas e não-tóxicas, impossíveis de diferenciação apenas pela morfologia. A principal toxina produzida pelas cianobactérias é a microcistina. Esta proteína é biossintetizada por um grupo de genes conhecidos como mcy. A detecção destes genes a partir de PCR permite a distinção das variedades tóxicas e não-tóxicas. Desse modo, o objetivo desse trabalho foi investigar a ocorrência de florações produtoras de toxinas em um rio tributário do reservatório de Rosana, via amplificação do gene mcyA por PCR. Foram coletadas duas amostras de água da subsuperfície. As duas amostras coletadas no rio do Corvo foram dominadas pela espécie Radiocystis...
Tipo: Toxicidade
Palavras-chave: Ecologia Cianobactéria; Toxina; PCR; Radiocystis fernandoi; McyA Genética Cyanobacteria; Toxins; PCR; Radiocystis fernandoi; McyA.
Ano: 2011
URL: http://periodicos.uem.br/ojs/index.php/ActaSciBiolSci/article/view/6802

LC50 of the Peptide Produced by the Entomopathogenic Fungus Nomuraea rileyi (Farlow) Samson Active Against Third Instar Larvae of Anticarsia gemmatalis (Lep.: Noctuidae)
Provedor de dados: 52
Autores: Onofre,Sideney Becker; Riveros Gonzalez,Raul; Messias,Cláudio Luiz; Azevedo,João Lúcio; Barros,Neiva Monteiro de.
The entomopathogenic fungus Nomuraea rileyi (Farlow) Samson produced a peptide active against Anticarsia gemmatalis 3rd instar larvae. To produce this peptide, N. rileyi was cultivated aerobically in Saboraud, maltose, yeast-extract broth at 26 ± 1ºC for 12 days, after which the medium was filtered and separated in a liquid/liquid extractor, concentrated and the peptide purified chromatographically. The crystals obtained were kept refrigerated until needed for LC50 analysis. The LC50 of this peptide against A. gemmatalis 3rd instar larvae was determined in triplicate experiments using solutions containing 1.0, 0.2, 0.1, 0.01, 0.001 and 0.0001 mg/ml of N. rileyi peptide. The results of these experiments were used to calculate a linear equation in which Y =...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Anticarsia gemmatalis; Nomuraea rileyi; Integrated control; Secondary metabolite; Toxins.
Ano: 2002
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132002000300004

Cyanobacterial toxins in Portugal: effects on aquatic animals and risk for human health
Provedor de dados: 56
Autores: Vasconcelos,V.M.
Toxic cyanobacteria are common in Portuguese freshwaters and the most common toxins are microcystins. The occurrence of microcystin-LR (MCYST-LR) has been reported since 1990 and a significant number of water reservoirs that are used for drinking water attain high levels of this toxin. Aquatic animals that live in eutrophic freshwater ecosystems may be killed by microcystins but in many cases the toxicity is sublethal and so the animals can survive long enough to accumulate the toxins and transfer them along the food chain. Among these, edible mollusks, fish and crayfish are especially important because they are harvested and sold for human consumption. Mussels that live in estuarine waters and rivers where toxic blooms occur may accumulate toxins without...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cyanobacteria; Toxins; Risk; Human health; Microcystins; Accumulation.
Ano: 1999
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1999000300001

Induction of neutralizing antibodies in mice immunized with scorpion toxins detoxified by liposomal entrapment
Provedor de dados: 56
The possibility of producing neutralizing antibodies against the lethal effects of scorpion toxins was evaluated in the mouse model by immunization with an immunogen devoid of toxicity. A toxic fraction (5 mg) from the venom of the scorpion Tityus serrulatus was entrapped in sphingomyelin-cholesterol liposomes. The liposomes were treated for 1 h at 37oC with a 1% (w/w) trypsin solution in 0.2 M sodium carbonate buffer, pH 8.3. This treatment led to a strong reduction in venom toxicity. Immunization was performed as follows: mice were injected sc with 20 µg of the liposome-entrapped toxic fraction on days 1 and 21 and a final injection (20 µg) was administered ip on day 36. After injection of the immunogen, all mice developed an IgG response which was shown...
Palavras-chave: Liposomes; Neutralizing antibodies; Tityus serrulatus; Immunization; Toxins.
Ano: 1997
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1997000700010

Occurrence of genes encoding enterotoxins in uropathogenic Escherichia coli isolates
Provedor de dados: 58
Autores: Mirzarazi,Mahsa; Rezatofighi,Seyedeh Elham; Pourmahdi,Mahdi; Mohajeri,Mohamad Reza.
To determine the presence of some toxins of diarrheagenic Escherichia coli (DEC) in uropathogenic E. coli (UPEC), 138 urinary tract infection (UTI)-causing UPECs were analyzed. The astA, set, sen and cdtB genes were detected in 13 (9.4%), 2 (1.3%), 13 (9.4%) and 0 (0%) of UPEC isolates respectively. The results show that some genes encoding toxins can be transferred from DEC pathotypes to UPECs therefore these isolates can transform into potential diarrhea-causing agents.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Uropathogenic Escherichia coli; Toxins; Phylogenetic groups; Set; Sen; AstA and cdt genes.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822015000100155

Clinical importance and representation of toxigenic and non-toxigenic Clostridium difficile cultivated from stool samples of hospitalized patients
Provedor de dados: 58
Autores: Stojanovic,Predrag; Kocic,Branislava; Stojanovic,Miodrag; Miljkovic-Selimovic,Biljana; Tasic,Suzana; Miladinovic-Tasic,Natasa; Babic,Tatjana.
The aim of this study was to fortify the clinical importance and representation of toxigenic and non-toxigenic Clostridium difficile isolated from stool samples of hospitalized patients. This survey included 80 hospitalized patients with diarrhea and positive findings of Clostridium difficile in stool samples, and 100 hospitalized patients with formed stool as a control group. Bacteriological examination of a stool samples was conducted using standard microbiological methods. Stool sample were inoculated directly on nutrient media for bacterial cultivation (blood agar using 5% sheep blood, Endo agar, selective Salmonella Shigella agar, Selenite-F broth, CIN agar and Skirrow's medium), and to selective cycloserine-cefoxitin-fructose agar (CCFA) (Biomedics,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Clostridium difficile; Diarrhea; Toxins.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822012000100023

Frequency of virulence genes in Escherichia coli strains isolated from piglets with diarrhea in the North Parana State, Brazil
Provedor de dados: 58
Autores: Vidotto,Marilda C.; Lima,Natália C.S. de; Fritzen,Juliana T.T.; Freitas,Júlio C. de; Venâncio,Emerson J.; Ono,Mario A.
Identification of Escherichia coli causing porcine postweaning diarrhea requires knowledge regarding the prevalent pathotypes within a given region. A total of 100Escherichia coli isolates from piglets with diarrhea in Londrina city, Parana State, South Brazil, were screened for the presence of genes for F4, F5, F6, F18, F41 fimbrial antigens by specific probes and for enterotoxins (STa, STb, LT and STx2e) by polymerase chain reaction (PCR). The results showed that 60% of the isolates were positive for one or more of the fimbrial antigens and 92% were positive at least for one of the virulence factors examined. Virulence factor genes detected were F4 (44%), F18 (38%), F5 (30%), F41 (32%), F6 (25%), LTp-I (71%), STa (40%), STb (47%) and STx2e (3%). Twenty...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Porcine Escherichia coli; Virulence genes; Postweaning diarrhea; Toxins.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822009000100035

Molecular typing of Clostridium perfringens isolated from swine in slaughterhouses from São Paulo State, Brazil
Provedor de dados: 65
Autores: Ferreira,Thais Sebastiana Porfida; Moreno,Andrea Micke; Almeida,Renata Rodrigues de; Gomes,Cleise Ribeiro; Gobbi,Debora Dirani Sena de; Filsner,Pedro Henrique Nogueira de Lima; Moreno,Marina.
Clostridium perfringens is an anaerobic Gram-positive bacterium known as common pathogen for humans, for domestic and wildlife animals. Although infections caused by C. perfringens type C and A in swine are well studied, just a few reports describe the genetic relationship among strains in the epidemiological chain of swine clostridioses, as well as the presence of the microorganism in the slaughterhouses. The aim of the present study was to isolate C. perfringens from feces and carcasses from swine slaughterhouses, characterize the strains in relation to the presence of enterotoxin, alpha, beta, epsilon, iota and beta-2 toxins genes, using polymerase chain reaction (PCR) and comparing strains by means of Pulsed field gel electrophoresis (PFGE)....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Clostridium perfringens; Swine; Slaughterhouse; PFGE; Carcass; Toxins.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782012000800020