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1.
J. venom. anim. toxins incl. trop. dis ; 28: e20210042, 2022. graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1360568

Resumo

Spider venoms induce different physio-pharmacological effects by binding with high affinity on molecular targets, therefore being of biotechnological interest. Some of these toxins, acting on different types of ion channels, have been identified in the venom of spiders of the genus Phoneutria, mainly from P. nigriventer. In spite of the pharmaceutical potential demonstrated by P. nigriventer toxins, there is limited information on molecules from venoms of the same genus, as their toxins remain poorly characterized. Understanding this diversity and clarifying the differences in the mechanisms of action of spider toxins is of great importance for establishing their true biotechnological potential. This prompted us to compare three different venoms of the Phoneutria genus: P. nigriventer (Pn-V), P. eickstedtae (Pe-V) and P. pertyi (Pp-V). Methods: Biochemical and functional comparison of the venoms were carried out by SDS-PAGE, HPLC, mass spectrometry, enzymatic activities and electrophysiological assays (whole-cell patch clamp). Results: The employed approach revealed that all three venoms had an overall similarity in their components, with only minor differences. The presence of a high number of similar proteins was evident, particularly toxins in the mass range of ~6.0 kDa. Hyaluronidase and proteolytic activities were detected in all venoms, in addition to isoforms of the toxins Tx1 and Tx2-6. All Tx1 isoforms blocked Nav1.6 ion currents, with slight differences. Conclusion: Our findings showed that Pn-V, Pe-V and Pp-V are highly similar concerning protein composition and enzymatic activities, containing isoforms of the same toxins sharing high sequence homology, with minor modifications. However, these structural and functional variations are very important for venom diversity. In addition, our findings will contribute to the comprehension of the molecular diversity of the venoms of the other species from Phoneutria genus, exposing their biotechnological potential as a source for searching for new active molecules.(AU)


Assuntos
Animais , Espectrometria de Massas/instrumentação , Venenos de Aranha/análise , Aranhas , Isoformas de Proteínas/biossíntese , Hialuronoglucosaminidase , Preparações Farmacêuticas
2.
J. Venom. Anim. Toxins incl. Trop. Dis. ; 25: e.20190030, Dec. 5, 2019. ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: vti-24666

Resumo

Background:Crude venom of the banded tiger waspVespa affinis contains a variety of enzymes including hyaluronidases, commonly known as spreading factors.Methods:The cDNA cloning, sequence analysis and structural modelling of V. affinis venom hyaluronidase (VesA2) were herein described. Moreover, heterologous expression and mutagenesis of rVesA2 were performed.Results:V. affinis venom hyaluronidase full sequence is composed of 331 amino acids, with four predicted N-glycosylation sites. It was classified into the glycoside hydrolase family 56. The homology modelling exhibited a central core (α/β)7 composed of Asp107 and Glu109, acting as the catalytic residues. The recombinant protein was successfully expressed in E. coli with hyaluronidase activity. A recombinant mutant type with the double point mutation, Asp107Asn and Glu109Gln, completely lost this activity. The hyaluronidase from crude venom exhibited activity from pH 2 to 7. The recombinant wild type showed its maximal activity at pH 2 but decreased rapidly to nearly zero at pH 3 and was completely lost at pH 4.Conclusion:The recombinant wild-type protein showed its maximal activity at pH 2, more acidic pH than that found in the crude venom. The glycosylation was predicted to be responsible for the pH optimum and thermal stability of the enzymes activity.(AU)


Assuntos
Animais , Venenos de Vespas/química , Elementos Estruturais de Proteínas , Proteínas Recombinantes , Hialuronoglucosaminidase
3.
J. venom. anim. toxins incl. trop. dis ; 25: e.20190030, 2019. ilus, tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1484761

Resumo

Background:Crude venom of the banded tiger waspVespa affinis contains a variety of enzymes including hyaluronidases, commonly known as spreading factors.Methods:The cDNA cloning, sequence analysis and structural modelling of V. affinis venom hyaluronidase (VesA2) were herein described. Moreover, heterologous expression and mutagenesis of rVesA2 were performed.Results:V. affinis venom hyaluronidase full sequence is composed of 331 amino acids, with four predicted N-glycosylation sites. It was classified into the glycoside hydrolase family 56. The homology modelling exhibited a central core (α/β)7 composed of Asp107 and Glu109, acting as the catalytic residues. The recombinant protein was successfully expressed in E. coli with hyaluronidase activity. A recombinant mutant type with the double point mutation, Asp107Asn and Glu109Gln, completely lost this activity. The hyaluronidase from crude venom exhibited activity from pH 2 to 7. The recombinant wild type showed its maximal activity at pH 2 but decreased rapidly to nearly zero at pH 3 and was completely lost at pH 4.Conclusion:The recombinant wild-type protein showed its maximal activity at pH 2, more acidic pH than that found in the crude venom. The glycosylation was predicted to be responsible for the pH optimum and thermal stability of the enzymes activity.


Assuntos
Animais , Elementos Estruturais de Proteínas , Hialuronoglucosaminidase , Proteínas Recombinantes , Venenos de Vespas/química
4.
Artigo em Inglês | VETINDEX | ID: vti-32121

Resumo

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 inhibitors (serpins), hyaluronidases, allergen-like toxins and histamine-releasing factors. The toxin belonging to the phospholipase-D family (also known as the dermonecrotic toxin) is the most studied class of brown spider toxins. This class of toxins single-handedly can induce inflammatory response, dermonecrosis, hemolysis, thrombocytopenia and renal failure. The functional role of the hyaluronidase toxin as a spreading factor in loxoscelism has also been demonstrated. However, the biological characterization of other toxins remains unclear and the mechanism by which Loxosceles toxins exert their noxious effects is yet to be fully elucidated. The aim of this review is to provide an insight into brown spider venom toxins and toxicology, including a description of historical data already available in the literature. In this review article, the identification processes of novel Loxosceles toxins by molecular biology and proteomic approaches, their biological characterization and structural description based on x-ray crystallography and putative biotechnological uses are described along with the future perspectives in this field.(AU)


Assuntos
Animais , Venenos de Aranha , Fosfolipase D , Metaloproteases , Inseticidas , Hialuronoglucosaminidase , Aranhas
5.
Ciênc. Anim. (Impr.) ; 27(1): 41-54, 2017. tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1472304

Resumo

O controle do ciclo celular é regulado por uma cascata de eventos coordenados que podem atuar influenciando na expressão ou repressão da atividade de proteínas relacionadas a retomada da meiose. Estudos indicam que a atividade dessas proteínas mostra-se tempo-dependente no processo de maturação in vitro (MIV). Esse trabalho teve o objetivo de avaliar a cinética da atividade quinase p34cdc2 durante a MIV de oócitos caninos. Ciência Animal 27(1), 2017. Os ovários foram obtidos de 40 cadelas submetidas à ovário-salpingo-histerectomia (OSH) eletiva. Após a OSH, os ovários foram imediatamente transportados a uma temperatura de 4 ºC. No laboratório, os ovários foram seccionados em fatias finas ("slicing"), para a liberação dos complexos cumulus-oócito (COCs). Apenas os COCs grau 1 foram selecionados e colocados em meio de maturação por um período de 24, 48 e 72 h de maturação. Após o cultivo, os COCs foram colocados em placas contendo solução de hialuronidase 0.2% para a retirada completa das células do Cumulus. A atividade da proteína p34cdc2 foi detectada por ELISA. Com base nos resultados verifica-se que a atividade da proteína mostra-se tempo-dependente, atingindo o pico após 48h de MIV (p<0,01). Após 72h, a atividade demonstrou um decréscimo. Com base neste estudo pode-se concluir que a proteína quinase p34cdc2 desempenha uma função de suma importância na progressão da meiose em cadelas. Dessa forma, a compreensão melhor dessa proteína assim como de outra que participam do processo de maturação poderá contribuir para o estabelecimento de meios mais adequados que melhorem significativamente as taxas dematuração.


The control of the cell cycle is regulated by a cascade of coordinated events that can act by influencing the expression or repression of the activity of proteins related to meiosis resumption. Studies have indicated that the activity of these proteins is time-dependent in the in vitro maturation process (IVM). This work aimed to evaluate the kinetics of the p34cdc2 kinase activity during IVM of canine oocytes. Ovaries were obtained from 40 bitches submitted to elective ovary-salpingo-hysterectomy (OSH). After OSH, ovaries were immediately transported at temperature of 4 °C. In the laboratory, ovaries were sliced for the release of cumulus-oocyte complexes (COCs). Only grade 1 COCs were selected and placed in maturation medium for a period of 24, 48 and 72 h of maturation. After culturing, COCs were plated of 0.2% hyaluronidase solution for complete removal of cumulus cells. The activity of the p34cdc2 protein was detected by ELISA. Based on the results, it was observed that the activity of the protein is time-dependent, peaking after 48 hours of IVM (p 0.01). After 72 hours, activity declined. Based on this study, it could be concluded that the p34cdc2 protein kinase plays a very important role in the meiosis progression in bitches. Thus, a better understanding of this protein as well as of others that participate in the maturation process may contribute to the establishment of more adequate media to significantly improve maturation rates.


Assuntos
Feminino , Animais , Cães , Meiose , Oócitos , /análise , Técnicas de Maturação in Vitro de Oócitos/métodos , Técnicas de Maturação in Vitro de Oócitos/veterinária
6.
Ciênc. Anim. (Impr.) ; 27(1): 41-54, 2017. tab, ilus
Artigo em Inglês | VETINDEX | ID: vti-18435

Resumo

O controle do ciclo celular é regulado por uma cascata de eventos coordenados que podem atuar influenciando na expressão ou repressão da atividade de proteínas relacionadas a retomada da meiose. Estudos indicam que a atividade dessas proteínas mostra-se tempo-dependente no processo de maturação in vitro (MIV). Esse trabalho teve o objetivo de avaliar a cinética da atividade quinase p34cdc2 durante a MIV de oócitos caninos. Ciência Animal 27(1), 2017. Os ovários foram obtidos de 40 cadelas submetidas à ovário-salpingo-histerectomia (OSH) eletiva. Após a OSH, os ovários foram imediatamente transportados a uma temperatura de 4 ºC. No laboratório, os ovários foram seccionados em fatias finas ("slicing"), para a liberação dos complexos cumulus-oócito (COCs). Apenas os COCs grau 1 foram selecionados e colocados em meio de maturação por um período de 24, 48 e 72 h de maturação. Após o cultivo, os COCs foram colocados em placas contendo solução de hialuronidase 0.2% para a retirada completa das células do Cumulus. A atividade da proteína p34cdc2 foi detectada por ELISA. Com base nos resultados verifica-se que a atividade da proteína mostra-se tempo-dependente, atingindo o pico após 48h de MIV (p<0,01). Após 72h, a atividade demonstrou um decréscimo. Com base neste estudo pode-se concluir que a proteína quinase p34cdc2 desempenha uma função de suma importância na progressão da meiose em cadelas. Dessa forma, a compreensão melhor dessa proteína assim como de outra que participam do processo de maturação poderá contribuir para o estabelecimento de meios mais adequados que melhorem significativamente as taxas dematuração.(AU)


The control of the cell cycle is regulated by a cascade of coordinated events that can act by influencing the expression or repression of the activity of proteins related to meiosis resumption. Studies have indicated that the activity of these proteins is time-dependent in the in vitro maturation process (IVM). This work aimed to evaluate the kinetics of the p34cdc2 kinase activity during IVM of canine oocytes. Ovaries were obtained from 40 bitches submitted to elective ovary-salpingo-hysterectomy (OSH). After OSH, ovaries were immediately transported at temperature of 4 °C. In the laboratory, ovaries were sliced for the release of cumulus-oocyte complexes (COCs). Only grade 1 COCs were selected and placed in maturation medium for a period of 24, 48 and 72 h of maturation. After culturing, COCs were plated of 0.2% hyaluronidase solution for complete removal of cumulus cells. The activity of the p34cdc2 protein was detected by ELISA. Based on the results, it was observed that the activity of the protein is time-dependent, peaking after 48 hours of IVM (p 0.01). After 72 hours, activity declined. Based on this study, it could be concluded that the p34cdc2 protein kinase plays a very important role in the meiosis progression in bitches. Thus, a better understanding of this protein as well as of others that participate in the maturation process may contribute to the establishment of more adequate media to significantly improve maturation rates.(AU)


Assuntos
Animais , Feminino , Cães , Proteína Quinase CDC2/análise , Oócitos , Meiose , Técnicas de Maturação in Vitro de Oócitos/métodos , Técnicas de Maturação in Vitro de Oócitos/veterinária
7.
J. Venom. Anim. Toxins incl. Trop. Dis. ; 22: [1-11], Dezembro 1, 2016. ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: vti-15696

Resumo

Wasp venom is a complex mixture containing proteins, enzymes and small molecules, including some of the most dangerous allergens. The greater banded wasp (Vespa tropica) is well-known for its lethal venom, whose one of the major components is a hyaluronidase (HAase). It is believed that the high protein proportion and activity of this enzyme is responsible for the venom potency. Methods: In the present study, cDNA cloning, sequencing and 3D-structure of Vespa tropica venom HAase were described. Anti-native HAase antibody was used for neutralization assay. Results: Two isoforms, VesT2a and VesT2b, were classified as members of the glycosidase hydrolase 56 family with high similarity (4297 %) to the allergen venom HAase. VesT2a gene contained 1486 nucleotide residues encoding 357 amino acids whereas the VesT2b isoform consisted of 1411 residues encoding 356 amino acids. The mature VesT2a and VesT2b are similar in mass and pI after prediction. They are 39119.73 Da/pI 8.91 and 39571.5 Da/pI 9.38, respectively. Two catalytic residues in VesT2a, Asp107 and Glu109 were substituted in VesT2b by Asn, thus impeding enzymatic activity. The 3D-structure of the VesT2s isoform consisted of a central core (/)7 barrel and two disulfide bridges. The five putative glycosylation sites (Asn79, Asn99, Asn127, Asn187 and Asn325) of VesT2a and the three glycosylation sites (Asn1, Asn66 and Asn81) in VesT2b were predicted. An allergenic property significantly depends on the number of putative N-glycosylation sites. The anti-native HAase serum specifically recognized to venom HAase was able to neutralize toxicity of V. tropica venom. The ratio of venom antiserum was 1:12. Conclusions: The wasp venom allergy is known to cause life-threatening and fatal IgE-mediated anaphylactic reactions in allergic individuals. Structural analysis was a helpful tool for prediction of allergenic properties including their cross reactivity among the vespid HAase.(AU)


Assuntos
Animais , Venenos de Vespas/administração & dosagem , Venenos de Vespas/análise , Venenos de Vespas/toxicidade , Hialuronoglucosaminidase/análise , Hialuronoglucosaminidase/classificação , Hialuronoglucosaminidase/toxicidade
8.
J. venom. anim. toxins incl. trop. dis ; 22: [1-11], 2016. ilus, tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1484667

Resumo

Wasp venom is a complex mixture containing proteins, enzymes and small molecules, including some of the most dangerous allergens. The greater banded wasp (Vespa tropica) is well-known for its lethal venom, whose one of the major components is a hyaluronidase (HAase). It is believed that the high protein proportion and activity of this enzyme is responsible for the venom potency. Methods: In the present study, cDNA cloning, sequencing and 3D-structure of Vespa tropica venom HAase were described. Anti-native HAase antibody was used for neutralization assay. Results: Two isoforms, VesT2a and VesT2b, were classified as members of the glycosidase hydrolase 56 family with high similarity (4297 %) to the allergen venom HAase. VesT2a gene contained 1486 nucleotide residues encoding 357 amino acids whereas the VesT2b isoform consisted of 1411 residues encoding 356 amino acids. The mature VesT2a and VesT2b are similar in mass and pI after prediction. They are 39119.73 Da/pI 8.91 and 39571.5 Da/pI 9.38, respectively. Two catalytic residues in VesT2a, Asp107 and Glu109 were substituted in VesT2b by Asn, thus impeding enzymatic activity. The 3D-structure of the VesT2s isoform consisted of a central core (/)7 barrel and two disulfide bridges. The five putative glycosylation sites (Asn79, Asn99, Asn127, Asn187 and Asn325) of VesT2a and the three glycosylation sites (Asn1, Asn66 and Asn81) in VesT2b were predicted. An allergenic property significantly depends on the number of putative N-glycosylation sites. The anti-native HAase serum specifically recognized to venom HAase was able to neutralize toxicity of V. tropica venom. The ratio of venom antiserum was 1:12. Conclusions: The wasp venom allergy is known to cause life-threatening and fatal IgE-mediated anaphylactic reactions in allergic individuals. Structural analysis was a helpful tool for prediction of allergenic properties including their cross reactivity among the vespid HAase.


Assuntos
Animais , Hialuronoglucosaminidase/análise , Hialuronoglucosaminidase/classificação , Hialuronoglucosaminidase/toxicidade , Venenos de Vespas/administração & dosagem , Venenos de Vespas/análise , Venenos de Vespas/toxicidade
9.
J. venom. anim. toxins incl. trop. dis ; 22: 28, 2016. tab, graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-954789

Resumo

Background: Wasp venom is a complex mixture containing proteins, enzymes and small molecules, including some of the most dangerous allergens. The greater banded wasp (Vespa tropica) is well-known for its lethal venom, whose one of the major components is a hyaluronidase (HAase). It is believed that the high protein proportion and activity of this enzyme is responsible for the venom potency. Methods: In the present study, cDNA cloning, sequencing and 3D-structure of Vespa tropica venom HAase were described. Anti-native HAase antibody was used for neutralization assay. Results: Two isoforms, VesT2a and VesT2b, were classified as members of the glycosidase hydrolase 56 family with high similarity (42-97 %) to the allergen venom HAase. VesT2a gene contained 1486 nucleotide residues encoding 357 amino acids whereas the VesT2b isoform consisted of 1411 residues encoding 356 amino acids. The mature VesT2a and VesT2b are similar in mass and pI after prediction. They are 39119.73 Da/pI 8.91 and 39571.5 Da/pI 9.38, respectively. Two catalytic residues in VesT2a, Asp107 and Glu109 were substituted in VesT2b by Asn, thus impeding enzymatic activity. The 3D-structure of the VesT2s isoform consisted of a central core (α/β)7 barrel and two disulfide bridges. The five putative glycosylation sites (Asn79, Asn99, Asn127, Asn187 and Asn325) of VesT2a and the three glycosylation sites (Asn1, Asn66 and Asn81) in VesT2b were predicted. An allergenic property significantly depends on the number of putative N-glycosylation sites. The anti-native HAase serum specifically recognized to venom HAase was able to neutralize toxicity of V. tropica venom. The ratio of venom antiserum was 1:12. Conclusions: The wasp venom allergy is known to cause life-threatening and fatal IgE-mediated anaphylactic reactions in allergic individuals. Structural analysis was a helpful tool for prediction of allergenic properties including their cross reactivity among the vespid HAase.(AU)


Assuntos
Animais , Venenos de Vespas , Vespas , Clonagem de Organismos , Glicosídeo Hidrolases , Hialuronoglucosaminidase
10.
Acta sci. vet. (Online) ; 44: 01-05, 2016. tab
Artigo em Inglês | VETINDEX | ID: vti-722702

Resumo

Background: Pasteurella multocida serotypes A and D are commonly associated with pneumonia and pleuritis in pigs. Different phenotypic techniques, such as hyaluronidase and acriflavine tests, and genotyping techniques, such as PCR, are used to distinguish between these serotypes. The objective of this study was to compare the capsular identification methods of type A and type D P. multocida isolated from pigs using both phenotypic (hyaluronidase and acriflavine tests) and genotypic (multiplex PCR) techniques. Materials, Methods & Results: A total of 44 lyophilized P. multocida isolates, obtained between 1981 and 1997 from pig farms at Rio Grande do Sul State, Brazil, were analyzed. The isolates were reactivated in Brain Heart Infusion (BHI) broth and cultured in BHI broth and blood agar supplemented with 5% sheep blood. Colony identity was further confirmed by evaluating colony morphology in blood agar and confirming the absence of growth on MacConkey agar. Bacteria in Tryptone Soy Agar (TSA) were used for the Triple Sugar Iron (TSI), Sulfide-Indole-Motility (SIM), and nitrate, glucose, lactose, sucrose and mannitol fermentation tests. For hyaluronidase test, P. multocida colonies were streaked transversally across the entire plate, approximately 3-5mm apart, in order to observe their lines of growth. Following this, a hyaluronidase producing strain of Staphylococcus aureus[...](AU)


Assuntos
Animais , Pasteurella multocida/isolamento & purificação , Hialuronoglucosaminidase/análise , Acriflavina/análise , Suínos/microbiologia , Reação em Cadeia da Polimerase Multiplex/veterinária
11.
Acta sci. vet. (Impr.) ; 44: 01-05, 2016. tab
Artigo em Inglês | VETINDEX | ID: biblio-1457433

Resumo

Background: Pasteurella multocida serotypes A and D are commonly associated with pneumonia and pleuritis in pigs. Different phenotypic techniques, such as hyaluronidase and acriflavine tests, and genotyping techniques, such as PCR, are used to distinguish between these serotypes. The objective of this study was to compare the capsular identification methods of type A and type D P. multocida isolated from pigs using both phenotypic (hyaluronidase and acriflavine tests) and genotypic (multiplex PCR) techniques. Materials, Methods & Results: A total of 44 lyophilized P. multocida isolates, obtained between 1981 and 1997 from pig farms at Rio Grande do Sul State, Brazil, were analyzed. The isolates were reactivated in Brain Heart Infusion (BHI) broth and cultured in BHI broth and blood agar supplemented with 5% sheep blood. Colony identity was further confirmed by evaluating colony morphology in blood agar and confirming the absence of growth on MacConkey agar. Bacteria in Tryptone Soy Agar (TSA) were used for the Triple Sugar Iron (TSI), Sulfide-Indole-Motility (SIM), and nitrate, glucose, lactose, sucrose and mannitol fermentation tests. For hyaluronidase test, P. multocida colonies were streaked transversally across the entire plate, approximately 3-5mm apart, in order to observe their lines of growth. Following this, a hyaluronidase producing strain of Staphylococcus aureus[...]


Assuntos
Animais , Acriflavina/análise , Hialuronoglucosaminidase/análise , Pasteurella multocida/isolamento & purificação , Suínos/microbiologia , Reação em Cadeia da Polimerase Multiplex/veterinária
12.
Braz. j. vet. res. anim. sci ; 52(3): 266-272, 20150000.
Artigo em Português | VETINDEX | ID: vti-86923

Resumo

The bitch has reproductive peculiarities that differentiate it from other species. Several experiments have been conducted to establish efficient protocols for maturation; however, the results appear to be unsatisfactory. In this respect, the reproductive female donor should be considered, since it can be a factor of variability of findings in this species. The objective of this study was to evaluate the relationship between the estrous cycle phases phase diestrus and anestrus on canine oocyte in vitro maturation (IVM). The ovaries were transported in sodium chloride 0.9% solution, and were cut into phosphate-buffered saline (PBS) and the cumulus-oocyte complexes (COCs) selected in tissue culture medium (TCM), supplemented with 199 HEPES. A total of 469 grade 1 oocytes were collected from bitches in anestrus and diestrus. These selected oocytes were transferred to the maturation medium for a period of 72 hours, then subjected to hyaluronidase solution and stained with Hoechst 33342 to assess nuclear configuration. The comparison of anestrus and diestrus phase showed no differences (p > 0.05) between the nuclear maturation stages. Thus, the phase of the estrous cycle did not influence the in vitro maturation of canine oocytes, increasing the rates of M-II in this species.(AU)


A cadela apresenta particularidades reprodutivas que a diferencia de outras espécies. Diversos experimentos têm sido realizados visando estabelecer protocolos eficientes para a maturação, entretanto os resultados mostram-se insatisfatórios. Nesse aspecto, a fase reprodutiva da fêmea doadora deve ser considerada, já que pode ser um fator de variabilidade dos achados ate então presenciados nessa espécie. O objetivo deste estudo foi avaliar a influencia das fases do ciclo estral (anestro e diestro) na maturação in vitro (MIV) de cadelas. Os ovários foram transportados em solução de cloreto de sódio 0,9% e seccionados em solução salina fosfato tamponado (PBS) e os complexos cumulus-oócito (COCs) selecionados em meio de cultura de tecidos (TCM) 199 suplementado com HEPES. Foram obtidos 469 oócitos grau 1 de cadelas em anestro e diestro. Esses oócitos selecionados foram transferidos para o meio de maturação por um período de 72 horas, sendo posteriormente submetidos a solução de hialuronidase e corados com HOESCHT 33342 para avaliação da configuração nuclear. A comparação das fases de anestro e diestro não revelou diferença (p > 0,05) entre os estágios de maturação nuclear. Dessa maneira, a fase do ciclo estral não influenciou na maturação in vitro de oócitos caninos, incrementando os índices de M-II nesta espécie.(AU)


Assuntos
Animais , Feminino , Cães , Ciclo Estral/fisiologia , Técnicas de Maturação in Vitro de Oócitos/veterinária , Fenômenos Reprodutivos Fisiológicos , Anestro , Estro , Hialuronoglucosaminidase
13.
J. Venom. Anim. Toxins incl. Trop. Dis. ; 21: 1-12, Nov. 10, 2015. ilus, tab
Artigo em Inglês | VETINDEX | ID: vti-759972

Resumo

Hyaluronidases are enzymes that mainly degrade hyaluronan, the major glycosaminoglycan of the interstitial matrix. They are involved in several pathological and physiological activities including fertilization, wound healing, embryogenesis, angiogenesis, diffusion of toxins and drugs, metastasis, pneumonia, sepsis, bacteremia, meningitis, inflammation and allergy, among others. Hyaluronidases are widely distributed in nature and the enzymes from mammalian spermatozoa, lysosomes and animal venoms belong to the subclass EC 3.2.1.35. To date, only five three-dimensional structures for arthropod venom hyaluronidases (Apis mellifera and Vespula vulgaris) were determined. Additionally, there are four molecular models for hyaluronidases fromMesobuthus martensii, Polybia paulista and Tityus serrulatus venoms. These enzymes are employed as adjuvants to increase the absorption and dispersion of other drugs and have been used in various off-label clinical conditions to reduce tissue edema. Moreover, a PEGylated form of a recombinant human hyaluronidase is currently under clinical trials for the treatment of metastatic pancreatic cancer. This review focuses on the arthropod venom hyaluronidases and provides an overview of their biochemical properties, role in the envenoming, structure/activity relationship, and potential medical and biotechnological applications.(AU)


Assuntos
Animais , Venenos de Artrópodes/análise , Venenos de Artrópodes/uso terapêutico , Animais Peçonhentos , Hialuronoglucosaminidase
14.
J. venom. anim. toxins incl. trop. dis ; 21: 1-12, 31/03/2015. ilus, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1484615

Resumo

Hyaluronidases are enzymes that mainly degrade hyaluronan, the major glycosaminoglycan of the interstitial matrix. They are involved in several pathological and physiological activities including fertilization, wound healing, embryogenesis, angiogenesis, diffusion of toxins and drugs, metastasis, pneumonia, sepsis, bacteremia, meningitis, inflammation and allergy, among others. Hyaluronidases are widely distributed in nature and the enzymes from mammalian spermatozoa, lysosomes and animal venoms belong to the subclass EC 3.2.1.35. To date, only five three-dimensional structures for arthropod venom hyaluronidases (Apis mellifera and Vespula vulgaris) were determined. Additionally, there are four molecular models for hyaluronidases fromMesobuthus martensii, Polybia paulista and Tityus serrulatus venoms. These enzymes are employed as adjuvants to increase the absorption and dispersion of other drugs and have been used in various off-label clinical conditions to reduce tissue edema. Moreover, a PEGylated form of a recombinant human hyaluronidase is currently under clinical trials for the treatment of metastatic pancreatic cancer. This review focuses on the arthropod venom hyaluronidases and provides an overview of their biochemical properties, role in the envenoming, structure/activity relationship, and potential medical and biotechnological applications.


Assuntos
Animais , Animais Peçonhentos , Hialuronoglucosaminidase , Venenos de Artrópodes/análise , Venenos de Artrópodes/uso terapêutico
15.
Artigo em Inglês | VETINDEX | ID: vti-10957

Resumo

Venom hyaluronidase (Hyase) contributes to the diffusion of venom from the inoculation site. In this work, we purified and characterized Hyase from the venom of Vitalius dubius (Araneae, Theraphosidae), a large theraphosid found in southeastern Brazil. Venom obtained by electrical stimulation of adult male and female V. dubius was initially fractionated by gel filtration on a Superdex® 75 column. Active fractions were pooled and applied to a heparin-sepharose affinity column. The proteins were eluted with a linear NaCl gradient.(AU)


Assuntos
Animais , Hialuronoglucosaminidase/análise , Venenos/administração & dosagem , Aranhas/classificação
16.
Artigo em Inglês | VETINDEX | ID: vti-10972

Resumo

Hyaluronate is one of the major components of extracellular matrix from vertebrates whose breakdown is catalyzed by the enzyme hyaluronidase. These enzymes are widely described in snake venoms, in which they facilitate the spreading of the main toxins in the victims body during the envenoming. Snake venoms also present some variants (hyaluronidases-like substances) that are probably originated by alternative splicing, even though their relevance in envenomation is still under investigation. Hyaluronidases-like proteins have not yet been purified from any snake venom, but the cDNA that encodes these toxins was already identified in snake venom glands by transcriptomic analysis. Herein, we report the cloning and in silico analysis of the first hyaluronidase-like proteins from a Brazilian snake venom.(AU)


Assuntos
Animais , Clonagem Molecular/métodos , Venenos de Víboras , Hialuronoglucosaminidase/análise
17.
J. venom. anim. toxins incl. trop. dis ; 20: 1-9, 04/02/2014. ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1484576

Resumo

Hyaluronate is one of the major components of extracellular matrix from vertebrates whose breakdown is catalyzed by the enzyme hyaluronidase. These enzymes are widely described in snake venoms, in which they facilitate the spreading of the main toxins in the victim’s body during the envenoming. Snake venoms also present some variants (hyaluronidases-like substances) that are probably originated by alternative splicing, even though their relevance in envenomation is still under investigation. Hyaluronidases-like proteins have not yet been purified from any snake venom, but the cDNA that encodes these toxins was already identified in snake venom glands by transcriptomic analysis. Herein, we report the cloning and in silico analysis of the first hyaluronidase-like proteins from a Brazilian snake venom.


Assuntos
Animais , Clonagem Molecular/métodos , Hialuronoglucosaminidase/análise , Venenos de Víboras
18.
J. venom. anim. toxins incl. trop. dis ; 20: 17, 04/02/2014. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-954729

Resumo

Background Hyaluronate is one of the major components of extracellular matrix from vertebrates whose breakdown is catalyzed by the enzyme hyaluronidase. These enzymes are widely described in snake venoms, in which they facilitate the spreading of the main toxins in the victim's body during the envenoming. Snake venoms also present some variants (hyaluronidases-like substances) that are probably originated by alternative splicing, even though their relevance in envenomation is still under investigation. Hyaluronidases-like proteins have not yet been purified from any snake venom, but the cDNA that encodes these toxins was already identified in snake venom glands by transcriptomic analysis. Herein, we report the cloning and in silicoanalysis of the first hyaluronidase-like proteins from a Brazilian snake venom.Methods The cDNA sequence of hyaluronidase was cloned from the transcriptome of Bothrops pauloensisvenom glands. This sequence was submitted to multiple alignment with other related sequences by ClustalW. A phylogenetic analysis was performed using MEGA 4 software by the neighbor joining (NJ) method.Results The cDNA from Bothrops pauloensis venom gland that corresponds to hyaluronidase comprises 1175 bp and codifies a protein containing 194 amino acid residues. The sequence, denominated BpHyase, was identified as hyaluronidase-like since it shows high sequence identities (above 83%) with other described snake venom hyaluronidase-like sequences. Hyaluronidases-like proteins are thought to be products of alternative splicing implicated in deletions of central amino acids, including the catalytic residues. Structure-based sequence alignment of BpHyase to human hyaluronidase hHyal-1 demonstrates a loss of some key secondary structures. The phylogenetic analysis indicates an independent evolution of BpHyal when compared to other hyaluronidases. However, these toxins might share a common ancestor, thus suggesting a broad hyaluronidase-like distribution among venomous snakes.Conclusions This work is the first report of a cDNA sequence of hyaluronidase from Brazilian snake venoms. Moreover, the in silico analysis of its deduced amino acid sequence opens new perspectives about the biological function of hyaluronidases-like proteins and may direct further studies comprising their isolation and/or recombinant production, as well as their structural and functional characterization.(AU)


Assuntos
Animais , Filogenia , Venenos de Serpentes , Clonagem Molecular , Bothrops , Hialuronoglucosaminidase
19.
Vet. zootec ; 21(3): 462-470, 2014. ilus, tab
Artigo em Português | VETINDEX | ID: biblio-1427687

Resumo

A baixa competência meiótica de oócitos caninos quando submetidos às condições artificiais de cultivo é considerada um grande obstáculo para o desenvolvimento de biotecnologias reprodutivas nessa espécie. As baixas taxas de MIV podem estar associadas ao tamanho dos oócitos recuperados das diferentes fases do ciclo estral. Assim, o objetivo desse trabalho é avaliar a relação entre as fases do ciclo estral - fase luteal e anestro, com o diâmetro oocitário de cadelas. Foram utilizadas 41 fêmeas caninas, com idades entre 6 meses e 7 anos, submetidas à ovariosalpingohisterectomia eletiva no Ambulatório de Reprodução de Pequenos Animais do Departamento de Reprodução Animal e Radiologia Veterinária, da Faculdade de Medicina Veterinária e Zootecnia da UNESP, Botucatu. Os ovários foram fatiados e selecionados apenas os COCs grau I, sendo submetidos à solução de hialuronidase a 2% para a retirada das células do cumulus. Após esse processo, os oócitos foram corados com 10 ug/ml de Hoechst 33342 para avaliação do diâmetro oocitário, sem a zona pelúcida. Os resultados não demonstraram diferença estatisticamente significativa entre os oócitos obtidos das fases de anestro e luteal (77.62 µm x 78.64 µm). Dessa forma, há a necessidade de novos estudos para que seja possível uma compreensão adequada de quais os fatores que possam estar interferindo na competência oocitária, não devendo-se considerar apenas um fator determinante já que a ação coordenada de diversos fatores contribui para o crescimento e desenvolvimento do oócito.


The low meiotic competence of canine oocytes when subjected to conditions of artificial cultive is considered a major obstacle to the development of reproductive biotechnologies in this species. Low rates of IVM may be linked to the size of oocytes recovered from different phases of the estrous cycle. The objective of this study is to evaluate the relationship between the phases of the estrous cycle - luteal phase and anestrus, with oocyte diameter of bitches. A total of 41 female dogs, aged 6 months to 7 years, subject to ovariosalpingohisterectomy elective in the Clinic of Small Animal Reproduction, Department of Animal Reproduction and Veterinary Radiology, School of Veterinary Medicine and Animal Science, UNESP, Botucatu. Ovaries were sliced and selected only those COCs grade I, being subjected to the, solution of 2% hyaluronidase to remove cumulus cells. After this process, the oocytes were stained with 10 ml of Hoechst 33342 for assessment of oocyte diameter without the zona pellucida. The results showed no statistically significant difference between the oocytes from anestrous and luteal phases (77.62 um x 78.64 µm). Thus, there is a need for further studies to be able to have a proper understanding of the factors that may be interfering with oocyte competence and should not be considered only a determining factor since the coordinated action of several factors contributing to the growth and developing oocyte.


La baja competencia meiótica de ovocitos caninos cuando se someten a condiciones de cultivo artificial se considera un obstáculo importante para el desarrollo de biotecnologías reproductivas de esta especie. Las bajas tasas de IVM puede estar relacionado con el tamaño de los ovocitos recuperados de las diferentes fases del ciclo estral. El objetivo de este estudio es evaluar la relación entre las fases del ciclo estral - fase lútea y anestro, con un diámetro de ovocitos de hembras. Un total de 41 hembras, con edades entre 6 meses a 7 años, conforme a ovariosalpingohisterectomy el trabajo electiva en la Clínica de Reproducción de Pequeños Animales, Departamento de Reproducción Animal y Radiología Veterinaria, Facultad de Medicina Veterinaria y Zootecnia, UNESP, Botucatu. Los ovarios fueron cortados y seleccionar sólo aquellos COCs grado I, se someten a la solución de 2% de hialuronidasa para eliminar las células del cumulus. Después de este proceso, los ovocitos se tiñeron con 10 g/ml de Hoechst 33342 para evaluar diámetro de los ovocitos sin zona de los ovarios pelúcida. Os rodajas y se selecciona sólo aquellos AOC grado I, siendo sometidos a solución de hialuronidasa de 2% para la retirada de los células del cumulus. Después de este proceso, los ovocitos se tiñeron con 10 g/ml de Hoechst 33342 para la evaluación del diámetro del ovocito sin la zona pelúcida. Los resultados no mostraron diferencias estadísticamente significativas entre los ovocitos de las fases lútea y en anestro (77,62 x 78,64 mm microM). Por lo tanto, hay una necesidad de más estudios para ser capaz de tener una adecuada comprensión de los factores que pueden interferir con la competencia de ovocitos y no debe considerarse simplemente un factor determinante ya que la acción coordinada de varios factores que contribuyen al crecimiento y desarrollo de los ovocitos.


Assuntos
Animais , Feminino , Cães , Oócitos/crescimento & desenvolvimento , Oócitos/ultraestrutura , Ciclo Estral/fisiologia
20.
Tese em Português | VETTESES | ID: vtt-216858

Resumo

Diversas oftalmopatoias afetam a qualidade visual dos animais de companhia, dentre elas a opaficificação dos cristalino ou catarata. Sob essas demandas de procedimentos corretivos eficazes e seguros, opta-se pela técnica de facectomia, que exige uma anestesia geral e bulbo ocular centralizado, midríase, acinesia do bulbo ocular, manutenção da pressão intraocular (PIO) e inibição do reflexo óculo-cardíaco (ROC) e como alternativa têm se empregado os bloqueios locais para realizar as exigências, afim de promover conforto e segurança para o paciente. Foi estudado a associação entre ropivacaína-clonidina-hialuronidase na anestesia peribulbar em cirurgias de facectomia em cães, avaliando-se parâmetros oculares e fisiológicos sistêmicos. O teste foi realizado em oito animais, utilizando-se dezesseis olhos, oito para o bloqueio anestésico (OB) e oito contralaterais para controle (OC). Realizou-se o bloqueio peribulbar em um único ponto com volume de 1 mL, contendo clonidina (1 g/kg), ropivacaína 1% (10 mg/mL) e hialuronidase (25 UTR) seguido da pré-medicação, indução e anestesia geral inalatória. Os parâmetros avaliados: PIO (medidas nos tempos 0, 1 e 10 minutos), diâmetro pupilar, centralização do bulbo ocular, latência e duração do bloqueio motor, frequência cardíaca, frequência respiratória, pressão arterial média, ritmo cardíaco, capnometria e temperatura retal. Os pacientes eram ASA 2 (75%) e ASA 3 (25%). O tempo cirúrgico foi de cerca de 72,87 ± 17,41 minutos no qual o tempo de midríase ocorreu em 67,75 ± 43,38 segundos, a centralização do bulbo ocular em 89,13 ± 38,23 segundos e a duração do bloqueio motor de 162 ± 18,9 minutos. A dilatação pupilar foi significativa após o bloqueio. Não houve mudanças significativas nos valores da PIO - T0 (OC: 13,13 ± 3,37 OB: 12,13 ± 1,76), TBP1 (OC: 13,50 ± 2,96 OB: 12,13 ± 2.37) e TBP10 (OC: 13,53 ± 4,18 OB: 12,75 ± 2,17). Não houve correlação significativa entre as doses recebidas de ropivacaína e o seu efeito no bloqueio, contudo, destacamos que as doses de ropivacaína foram todas abaixo dos limites terapêuticos. Os parâmetros fisiológicos foram esperados de um procedimento anestésico e retornaram aos valores basais após o despertar, sem complicações. Não foi relatada ocorrência de ROC ou qualquer complicação referente à técnica do bloqueio peribulbar em quaisquer pacientes. Conclui-se que o bloqueio peribulbar para facectomia utilizando-se a associação ropivacaína 1% - clonidina (1 g/kg) hialuronidase (25UTR) numa solução de 1 mL promove baixa latência, boa duração, midríase adequadas para a facectomia e sem efeitos adversos.


A wide range of ophtalmopathies affects animals visual quality as in lens opacification or cataract. To adress this, safer and efficient corrections are demanded and facectomy is the ellected thecnique, which, demands a general anesthesia, centralization and acenesia of ocular bulb, mydriasis, maintenance do intraocular pressure (IOP) and inhibition of ocularcardiac reflexes (OCR). Alternatively, to general anesthesia, local block is preferred bacause if promotes the other signs safely and provides more comfort to the patient. WE investigated the association of clonidine-hyaluronidase-ropivacaine in peribulbar anesthesia in dogs evaluating ocular and sistemic physiological parameters. Eight animals were investigated, counted 16 eyes, arrangeg 8 eyes for local block (OB) and the controlateral was defined as control (n=8, OC) . We performed a single-point low-volume (1.0 ml) thechnique. Injection volume contained clonidine (1 g/kg), hyaluronidase (25 UTR) and ropivacaine 1% (10mg/mL) and was followed by premedication, induction and inhalatory general anesthesia. We evaluated parameters at time 0 (T0) before peribulbar block, and post peribulbar block at 1 minute (T1) and at 10 mintues for IOP; we measured pupilar diameter, latency and time duration of motor block, akinesia and centralization of eye bulb as well as physiological parameters as cardiac and respiratory rate and frequency, mean arterial pressure, cardiac rhythm, capynometry and rectal temperature. Patients were rated as ASA 2 (75%) and ASA 3 (25%). Facectomy time extended for 72.87± 17.41 minutes, in which, mydriasis ocorrued at 67.75 ± 43.38 seconds; bulb centralizations at 67.75 ± 43.38 seconds; motor block extended for 162 ± 18.9 minutes. Pupilar dialation was significant after peribulbar block. No significant rate was observed for IOP - T0 (OC: 13.13 ± 3.37 OB: 12.13 ± 1.76), TBP1 (OC: 13.50 ± 2.96 OB: 12.13 ± 2.37) e TBP10 (OC: 13.53 ± 4.18 OB: 12.75 ± 2.17). No positive correlation between ropivacaine dose and peribulbar block effect could be determined, however, we detach that ropivacaine dosage for each animal was below the indicated therapeutcis limits for the specie. Physiological parameter were considered normally observed along the anesthesia procedure and reverted to basal rates at recovery and no complications were diagnosed. In all patientes, OCR or any complication relationed to peribulbar block were not observed. We conclude that periblubar block for facectomy using clonidine-hyaluronidase-ropivacaine (C-H-R) association in a 1 mL volume promotes low latency, long duration and mydriasis with no side effects.

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