Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 20
Filtrar
Mais filtros











Intervalo de ano de publicação
1.
Int Arch Occup Environ Health ; 89(6): 991-6, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27142971

RESUMO

PURPOSE: The aim of this pilot study was to evaluate surface contamination by platinum drugs in the environment of patients in ICUs and wards treated by hyperthermic intraperitoneal chemotherapy (HIPEC). METHODS: The monitoring included 12 HIPEC treatments from four hospitals during the following 3 days after perfusion. A total of 33 urine and 33 drainage fluids from HIPEC patients and 160 wipe samples from several surfaces (urine/drainage bags, floors, gloves) were taken during the study period. RESULTS: In urine, the highest platinum concentrations were measured on the first day after perfusion. Median platinum concentrations were 1260 ng/ml for patients after cisplatin perfusion and 11,000 ng/ml for oxaliplatin treatment. Concentrations decreased until day three to 413 ng/ml cisplatin and 529 ng/ml oxaliplatin, respectively. In drainage liquids, platinum concentrations were generally lower. Platinum concentrations from surfaces of bags and floors ranged from 0.01 to 439 pg/cm(2) (median: urine bag 2.77 pg/cm(2), drainage bag 0.22 pg/cm(2), floor left 0.14 pg/cm(2), floor right 0.24 pg/cm(2)), with the highest contamination found on the outer surface of the urine bags. Samples from nurses' protective gloves ranged between 0.03 and 12 pg/cm(2) (median: 0.2 pg/cm(2)). CONCLUSIONS: High platinum-drug concentrations in urine and drainage liquids are the main source of contamination. Therefore, safe handling of these liquids is the best way to avoid cross-contamination on surfaces in wards and ICUs. Our results show that it is possible to take care of HIPEC patients without high contaminations during the first 3 days.


Assuntos
Antineoplásicos/análise , Cisplatino/análise , Monitoramento Ambiental/métodos , Unidades de Terapia Intensiva , Compostos Organoplatínicos/análise , Quartos de Pacientes , Luvas Protetoras , Humanos , Exposição Ocupacional/análise , Oxaliplatina , Projetos Piloto
2.
Occup Environ Med ; 62(5): 330-6, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15837855

RESUMO

BACKGROUND: N,N-dimethylformamide (DMF) was recently prioritised for field studies by the National Toxicology Program based on the potency of its reproductive toxic effects. AIMS: To measure accurately exposure to DMF in occupational settings. METHODS: In 35 healthy workers employed in the polyacrylic fibre industry, N-methylformamide (NMF) and N-acetyl-S-(N-methylcarbamoyl)cysteine (AMCC) in urine, and N-methylcarbamoylated haemoglobin (NMHb) in blood were measured. Workplace documentation and questionnaire information were used to categorise workers in groups exposed to low, medium, and high concentrations of DMF. RESULTS: All three biomarkers can be used to identify occupational exposure to DMF. However, only the analysis of NMHb could accurately distinguish between workers exposed to different concentrations of DMF. The median concentrations were determined to be 55.1, 122.8, and 152.6 nmol/g globin in workers exposed to low, medium, and high concentrations of DMF, respectively. It was possible by the use of NMHb to identify all working tasks with increased exposure to DMF. While fibre crimpers were found to be least exposed to DMF, persons washing, dyeing, or towing the fibres were found to be highly exposed to DMF. In addition, NMHb measurements were capable of uncovering working tasks, which previously were not associated with increased exposure to DMF; for example, the person preparing the fibre forming solution. CONCLUSIONS: Measurement of NMHb in blood is recommended rather than measurement of NMF and AMCC in urine to accurately assess exposure to DMF in health risk assessment. However, NMF and AMCC are useful biomarkers for occupational hygiene intervention. Further investigations regarding toxicity of DMF should focus on highly exposed persons in the polyacrylic fibre industry. Additional measurements in occupational settings other than the polyacrylic fibre industry are also recommended, since the population at risk and the production volume of DMF are high.


Assuntos
Acetilcisteína/análogos & derivados , Biomarcadores/análise , Dimetilformamida/toxicidade , Higiene , Exposição Ocupacional/efeitos adversos , Solventes/toxicidade , Indústria Têxtil , Acetilcisteína/química , Acetilcisteína/urina , Adulto , Carbamatos/análise , Carbamatos/química , Dimetilformamida/química , Formamidas/análise , Formamidas/química , Meia-Vida , Substâncias Perigosas/análise , Hemoglobinas/análise , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco/métodos
3.
Neurology ; 63(6): 1124-6, 2004 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-15452317

RESUMO

A retrospective review of the safety, tolerability, and efficacy of vagus nerve stimulation (VNS) in 48 patients with intractable partial epilepsy was performed. Side effects were few and mild to moderate. Mean seizure frequency decreased by 26% after 1 year, 30% after 5 years, and 52% after 12 years with VNS treatment.


Assuntos
Terapia por Estimulação Elétrica , Epilepsias Parciais/terapia , Nervo Vago/fisiopatologia , Adolescente , Adulto , Criança , Pré-Escolar , Terapia por Estimulação Elétrica/efeitos adversos , Terapia por Estimulação Elétrica/instrumentação , Eletrodos Implantados , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Aceitação pelo Paciente de Cuidados de Saúde , Pacientes Desistentes do Tratamento , Estudos Retrospectivos , Resultado do Tratamento
4.
J Dairy Sci ; 87(7): 2293-8, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15328244

RESUMO

Longevity is the economically most important functional trait in cattle populations. However, with an increased productive lifespan, the number of offspring born by older dams increases. A higher maternal age might have negative effects on the performance of offspring. The objective of this study was to investigate the effect of maternal age on production (energy-corrected milk yield [ECM]) and functional traits (fertility; somatic cell score, and functional longevity) in Austrian dual-purpose Simmental cows. Age of dam had a significant effect on ECM yield and longevity. The ECM yield of daughters decreased with age of dam. Although the risk of culling slightly increased with age of dam, it was lowest for daughters of oldest dams. Results for fertility were non-significant, and results for somatic cell scores were inconsistent across parities.


Assuntos
Envelhecimento/fisiologia , Bovinos/fisiologia , Fertilidade/fisiologia , Lactação/fisiologia , Longevidade/fisiologia , Idade Materna , Animais , Metabolismo Energético , Feminino , Masculino , Paridade , Gravidez , Software
5.
Phys Rev Lett ; 92(20): 207402, 2004 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-15169382

RESUMO

Using soft-x-ray absorption spectroscopy at the Co L(2,3) and O K edges, we demonstrate that the Co3+ ions with the CoO5 pyramidal coordination in the layered Sr2CoO3Cl compound are unambiguously in the high spin state. Our result questions the reliability of the spin state assignments made so far for the recently synthesized layered cobalt perovskites and calls for a reexamination of the modeling for the complex and fascinating properties of these new materials.

6.
Arch Biochem Biophys ; 367(1): 26-32, 1999 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-10375395

RESUMO

This paper describes the isolation and primary structure analysis of a new phospholipase A2 with platelet-aggregation-inhibiting activity from the venom of Bothrops jararaca. The protein, named BJ-PLA2, was isolated by means of ammonium sulfate precipitation and anion-exchange and reversed-phase chromatographies and behaved as a homogeneous single-chain protein on SDS-PAGE. Its amino acid sequence was determined by N-terminal sequencing and analysis of overlapped chemical and proteolytic fragments by automated Edman degradation and mass spectometry determination. BJ-PLA2 consists of 124 amino acid residues and has the structural features of snake venom class II phospholipases A2. Chemical modification with p-bromophenacylbromide caused complete loss of enzymatic activity and partially affected the platelet-aggregation-inhibiting activity of BJ-PLA2.


Assuntos
Fosfolipases A/metabolismo , Inibidores da Agregação Plaquetária/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Venenos de Serpentes/enzimologia , Acetofenonas/metabolismo , Difosfato de Adenosina/antagonistas & inibidores , Difosfato de Adenosina/farmacologia , Alquilação , Sequência de Aminoácidos , Animais , Sítios de Ligação , Bothrops , Precipitação Química , Cromatografia Líquida , Colágeno/antagonistas & inibidores , Colágeno/farmacologia , Humanos , Concentração Inibidora 50 , Camundongos , Dados de Sequência Molecular , Peso Molecular , Fosfolipases A/química , Fosfolipases A/isolamento & purificação , Fosfolipases A/farmacologia , Fosfolipases A2 , Inibidores da Agregação Plaquetária/química , Inibidores da Agregação Plaquetária/isolamento & purificação , Inibidores da Agregação Plaquetária/metabolismo , Homologia de Sequência de Aminoácidos
7.
Toxicon ; 36(10): 1407-21, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9723839

RESUMO

A myotoxin has been isolated from the Duvernoy's gland (DG) secretion of the xenodontine colubrid Philodrvas olfersii (green snake) by gel filtration on Sephadex G-100 SF. Under non-reducing and reducing conditions in SDS-PAGE, the myotoxin migrates as a single band with a mol. wt. of 20000. The toxin has 182 amino acid residues (approximately 20% acidic), a pI of 4.8 and a blocked N-terminal. In the chick biventer cervicis preparation, P. olfersii myotoxin partially blocks potassium-evoked contractures without affecting either the twitch-tension resulting from indirect stimulation or the contractures evoked by acetylcholine. Both the DG secretion and the myotoxin increase the serum creatine kinase (CK) levels of mice and stimulate the release of CK from the biventer cervicis preparation in a dose- and time-dependent manner. The varying degrees of muscle cell lysis and extensive widening of the intercellular spaces caused by the DG secretion are reproduced by the myotoxin, with the exception that in the latter the partial or total loss of transverse muscle striations is restricted to the muscle periphery. This myotoxin is the first such protein to be characterized from a DG secretion.


Assuntos
Colubridae , Glândulas Exócrinas/metabolismo , Músculos do Pescoço/efeitos dos fármacos , Junção Neuromuscular/efeitos dos fármacos , Venenos de Serpentes/toxicidade , Acetilcolina/farmacologia , Animais , Bothrops , Galinhas , Cromatografia em Gel , Creatina Quinase/metabolismo , Venenos de Crotalídeos/toxicidade , Relação Dose-Resposta a Droga , Estimulação Elétrica , Eletroforese em Gel de Poliacrilamida , Técnicas In Vitro , Masculino , Camundongos , Contração Muscular/efeitos dos fármacos , Músculos do Pescoço/patologia , Músculos do Pescoço/fisiologia , Junção Neuromuscular/patologia , Junção Neuromuscular/fisiologia , Cloreto de Potássio/farmacologia , Venenos de Serpentes/química , Venenos de Serpentes/metabolismo , Especificidade da Espécie , Fatores de Tempo
8.
Toxicon ; 36(1): 31-9, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9604280

RESUMO

Two peptides with kinin-like biological properties were isolated by chromatography on a Sephadex G-10 column followed by high-performance liquid chromatography, from the venom of the spider Scaptocosa raptoria. The isolated peptides (peptide-S and peptide-R) were shown to cause contraction on the isolated guinea-pig ileum at amounts equivalent to those shown by bradykinin. Both peptides relaxed the isolated rat duodenum, increased the capillary permeability, caused decreasing and biphasic effect of the arterial blood pressure in conscious rats and induced oedema in the rat paw. The peptides had activity and structural similarities to other peptides (kinin-like) isolated from venoms. The complete amino acid analysis gave peptide-S a structure with 36 amino acid residues and peptide-R 22 amino acid residues. The mol. wts were estimated to be in the range of 4000 and 2870, respectively.


Assuntos
Músculo Liso/efeitos dos fármacos , Venenos de Aranha/isolamento & purificação , Sequência de Aminoácidos , Animais , Permeabilidade Capilar/efeitos dos fármacos , Feminino , Cobaias , Masculino , Dados de Sequência Molecular , Contração Muscular/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Venenos de Aranha/farmacologia , Relação Estrutura-Atividade
9.
Gen Comp Endocrinol ; 109(3): 336-46, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9480741

RESUMO

Peaks corresponding to arg-vasotocin obtained by HPLC from Sep-Pak C18 column extracts of Bothrops jararaca plasma were identified by radioimmunoassay and amino acid analysis. Plasma vasotocin and protein levels, osmolality, and L-cystine-di-beta-naphthylamidase were also compared in snakes under normal hydration conditions with or without chronic administration of vasotocin or in the presence of chronic hydroosmotic challenges. Sep-Pak C18 and radioimmunoassay were validated for the extraction and determination of this peptide, respectively (about 80% recovery). EDTA presented a protective action on this recovery compared to the use of heparin as anticoagulant for snake blood. A reduction of vasotocin content related to the time of incubation of this peptide added to snake plasma was detected by radioimmunoassay. Snake plasma activity also on L-cystine-di-beta-naphthylamide indicated that this vasotocin-destroying effect was due to hydrolysis by a cystine-aminopeptidase-like activity. Plasma levels of vasotocin revealed an unexpected dispersion and absent correlation with plasma levels of osmolality. Measurable vasotocin in a large number of snakes associated with lower levels of l-cystine-di-beta-naphthylamidase in acute than in chronic salt loading suggested the role of this enzyme activity in long-term regulation of the vasotocin system in this snake.


Assuntos
Bothrops/sangue , Bothrops/fisiologia , Vasotocina/sangue , Água/metabolismo , Aminoácidos/sangue , Aminopeptidases/sangue , Animais , Cromatografia Líquida de Alta Pressão , Cistina/sangue , Feminino , Privação de Alimentos , Hidrólise , Masculino , Concentração Osmolar , Radioimunoensaio , Caracteres Sexuais , Cloreto de Sódio/administração & dosagem , Privação de Água
10.
Biochem J ; 324 ( Pt 2): 517-22, 1997 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-9182712

RESUMO

A systematic analysis of the peptide sequences and lengths of several homologues of bioactive peptides and of a number of quenched-fluorescence (qf) opioid- and bradykinin-related peptides was performed to determine the main features leading the oligopeptides to hydrolysis by the recombinant rat testis thimet oligopeptidase (EC 3.4.24.15). The results indicate that a minimum substrate length of six amino acids is required and that among the oligopeptides six to thirteen amino acid residues long, their susceptibility as substrates is highly variable. Thimet oligopeptidase was able to hydrolyse, with similar catalytic efficiency, peptide bonds having hydrophobic or hydrophilic amino acids as well as proline in the P1 position of peptides, ranging from a minimum of six to a maximum of approximately thirteen amino acid residues. An intriguing observation was the shift of the cleavage site, at a Leu-Arg bond in qf dynorphin-(2-8) [qf-Dyn2-8; Abz-GGFLRRV-EDDnp, where Abz stands for o-aminobenzoyl and EDDnp for N-(2,4-dinitrophenyl)ethylenediamine], to Arg-Arg in qf-Dyn2-8Q, in which Gln was substituted for Val at its C-terminus. Similarly, a cleavage site displacement was also observed with the hydrolysis of the internally quenched-fluorescence bradykinin analogues containing Gln at the C-terminal position, namely Abz-RPPGFSPFR-EDDnp and Abz-GFSPFR-EDDnp are cleaved at the Phe-Ser bond, but Abz-RPPGFSPFRQ-EDDnp and Abz-GFSPFRQ-EDDnp are cleaved at the Pro-Phe bond.


Assuntos
Metaloendopeptidases/metabolismo , Oligopeptídeos/química , Sequência de Aminoácidos , Animais , Bradicinina/metabolismo , Fenômenos Químicos , Físico-Química , Dinorfinas/metabolismo , Hidrólise , Masculino , Dados de Sequência Molecular , Oligopeptídeos/metabolismo , Ratos , Proteínas Recombinantes de Fusão/metabolismo , Relação Estrutura-Atividade , Especificidade por Substrato , Testículo/enzimologia
11.
Toxicon ; 32(7): 819-31, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7940589

RESUMO

Five distinct fibrin(ogen)olytic proteinases PofibC1, C2, C3, H and S were isolated by gel filtration and ion-exchange chromatographies. PofibC1, C2, C3 and H are metalloproteinases inhibited by ethylenediamine tetracetic acid (EDTA) or 1,10-phenanthroline. Only PofibH had hemorrhagic activity. PofibS is a serine proteinase, inhibited by phenylmethylsulfonyl fluoride (PMSF) or Torresea cearensis trypsin inhibitor (TCTI). All five enzymes were inhibited by dithiothreitol (DTT) or dithioerythritol (DTE). PofibC1 and C2 presented the same mol. wt of 47,000 and are acidic proteins of pI 6.2 PofibC3 is a basic proteinase of pI 8.5 and mol. wt 45,000. The hemorrhagic proteinase PofibH had a mol. wt of 58,000 and pI of 4.6 and PofibS had a mol. wt of 36,000 and pI of 4.5. The five proteinases degraded fibrin and fibrinogen. PofibC1, C2, C3 and H degraded preferentially A alpha-chains while PofibS cleaved concomitantly A alpha and B beta-chains of fibrinogen. None of these enzymes cleaved the gamma-chain of fibrinogen. When correlated with the thrombin delay time, the most active was PofibS, while PofibH and PofibC1 showed almost no activity. The proteinases also differed in the peptide cleavage of B-chain of insulin. Philodryas olfersii venom promoted in vivo a loss of the circulant plasma fibrinogen, as was observed in experiments with rats.


Assuntos
Colubridae , Fibrina/metabolismo , Fibrinogênio/metabolismo , Venenos de Serpentes/enzimologia , Sequência de Aminoácidos , Animais , Caseínas/metabolismo , Eletroforese em Gel de Poliacrilamida , Hemorragia/induzido quimicamente , Humanos , Insulina/metabolismo , Focalização Isoelétrica , Masculino , Camundongos , Dados de Sequência Molecular , Ratos , Venenos de Serpentes/toxicidade , Tempo de Trombina
12.
Toxicon ; 31(11): 1479-82, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8310448

RESUMO

The hydrolytic activity of three basic proteinases isolated from Bothrops moojeni venom was determined on the B-chain of oxidized insulin. The serine proteinases MSP1 and MSP2 cleave the insulin B-chain at identical positions and in the same order of bond cleavage. Cleavage occurs first at the Arg-Gly(22-23) position, followed by hydrolysis of the Lys-Ala(29-30) peptide bond. The metalloproteinase MPB differs from the serine proteinases in cleaving the insulin B-chain very rapidly at four positions: Ser-His(9-10), Ala-Leu(14-15), Tyr-Leu(16-17) and Phe-Phe(24-25).


Assuntos
Bothrops , Venenos de Crotalídeos/enzimologia , Insulina/metabolismo , Metaloendopeptidases/metabolismo , Serina Endopeptidases/metabolismo , Sequência de Aminoácidos , Animais , Cromatografia Líquida de Alta Pressão , Hidrólise , Metaloproteases , Dados de Sequência Molecular
13.
Toxicon ; 31(2): 187-94, 1993 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8456446

RESUMO

Moojeni protease A, a proteolytic enzyme isolated from Bothrops moojeni venom, hydrolyzes type I collagen, gelatin, fibrinogen, fibrin and the B-chain of oxidized insulin. The proteinase cleaves the A alpha-chain faster than the B beta-chain of human fibrinogen and shows no effect on the gamma-chain. Fibrin solubilization appears to occur from the hydrolysis of the alpha-polymer and unpolymerized alpha-chain. The enzyme cleaves the Ala(14)-Leu(15) bond of the oxidized insulin B-chain most rapidly, followed by splitting the Ser(9)-His(10) bond. The Tyr(16)-Leu(17) and Gly(20)-Glu(21) cleavage sites were hydrolyzed slightly more slowly, while the peptide bonds His(5)-Leu(6), His(10)-Leu(11), Glu(21)-Arg(22), Gly(23)-Phe(24) and Phe(24)-Phe(25) were more resistant to the enzyme attack. Small synthetic peptides were not hydrolyzed by moojeni protease A.


Assuntos
Venenos de Crotalídeos/enzimologia , Metaloendopeptidases/metabolismo , Sequência de Aminoácidos , Colágeno/metabolismo , Fibrina/metabolismo , Fibrinogênio/metabolismo , Gelatina/metabolismo , Hidrólise , Insulina/metabolismo , Metaloendopeptidases/isolamento & purificação , Dados de Sequência Molecular , Peptídeos/química , Especificidade por Substrato
14.
Toxicon ; 24(9): 943-6, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3810664

RESUMO

Compared to the crude velonom of Bothrops jararaca, which needs 5000 ng to produce a hemorrhagic spot of 1 cm2 on rabbit skin, the isolated hemorrhagic factors HF1, HF2 and HF3 require 100, 20 and 15 ng of protein, respectively. Although these hemorrhagic factors possess different biochemical and biophysical properties, they are immunologically related proteins. The hemorrhagic, as well as the proteolytic, activities of these factors are destroyed by EDTA, acidic pH or heat treatments.


Assuntos
Venenos de Crotalídeos/isolamento & purificação , Animais , Cromatografia DEAE-Celulose , Cromatografia em Gel , Venenos de Crotalídeos/imunologia , Eletroforese em Gel de Poliacrilamida , Focalização Isoelétrica , Peso Molecular , Coelhos
15.
Braz J Med Biol Res ; 18(3): 337-40, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3835983

RESUMO

The local tissue effects of crude Bothrops neuwiedi snake venom and of its hemorrhagic factor (NHF) were studied on mouse tibialis anterior muscle in vivo. After 6 h, 8 days and 6 weeks the muscles were examined in paraffin sections stained with hematoxylin and eosin. Both NHF and crude venom produced hemorrhage and myonecrosis, later followed by muscle fiber regeneration. Intramuscular arteries also suffered necrosis. The minimal dose of NHF necessary to produce detectable hemorrhage and myonecrosis was 50 ng, while the minimal venom dose needed to produce the same effect was 20 times higher. The results indicate that NHF is one of the major factors responsible for the local effects of B. neuwiedi venom.


Assuntos
Venenos de Crotalídeos/toxicidade , Músculos/patologia , Animais , Hemorragia , Camundongos , Necrose
16.
Toxicon ; 23(4): 691-706, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3933145

RESUMO

Moojeni protease A was purified from the venom of Bothrops moojeni by chromatography on Sephadex G-100, DEAE Sephadex A-50 and rechromatography on Sephadex G-100. The enzyme shows one protein band in polyacrylamide gel electrophoresis at pH 8.5 or at pH 4.3. The pI of moojeni protease A was approximately 7.7. In immunoelectrophoresis it migrates to the cathode. The enzyme was homogeneous by polyacrylamide gel electrophoresis, immunoelectrophoresis and analyses in the ultracentrifuge. The S20,w and D20,w are 2.68 S and 10.34 X 10(-7) cm2/sec, respectively. The molecular weight calculated by s/D ratio was 22,500 and a value of 22,800 was obtained by sedimentation equilibrium. In SDS-polyacrylamide gel electrophoresis the enzyme exhibits a single polypeptide chain of approximately 20,400 mol. wt under denaturating conditions. In water or low salt solution it undergoes denaturation and autolysis. The enzyme is also unstable at acidic pH and to heat treatment and precipitates in the presence of metal chelating compounds such as EDTA or 1,10 phenanthroline. Leucine, the NH2-terminal amino acid of moojeni protease A is blocked after EDTA treatment. The proteolytic activity of this enzyme increases about 20% in the presence of Ca2+; Mg2+ has no effect and other divalent cations cause inhibition. The removal of Ca2+ ions by oxalate causes about 20% inhibition; the activity was restored by addition of Ca2+.


Assuntos
Venenos de Crotalídeos/análise , Endopeptidases/isolamento & purificação , Metaloendopeptidases , Peptídeo Hidrolases/isolamento & purificação , Animais , Ácido Edético/farmacologia , Eletroforese em Gel de Poliacrilamida , Endopeptidases/análise , Hemorragia/induzido quimicamente , Concentração de Íons de Hidrogênio , Metaloproteínas/análise , Metais/farmacologia , Peptídeo Hidrolases/análise , Fosfolipases A/análise , Coelhos , Ultracentrifugação
17.
Toxicon ; 23(2): 341-5, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3895580

RESUMO

Haemorrhagic factor HF2 and bothropasin, two metalloproteins isolated from the venom of Bothrops jararaca, caused haemorrhage followed by myonecrosis and arterial necrosis after i.m. injection in mice. The effects of HF2 were qualitatively similar to those of bothropasin and crude B. jararaca venom, but its potency was about 20 times higher. The haemorrhagic and necrotizing actions of these components are unrelated to their proteolytic activity on casein.


Assuntos
Venenos de Crotalídeos/toxicidade , Hemorragia/induzido quimicamente , Doenças Musculares/induzido quimicamente , Peptídeo Hidrolases/toxicidade , Animais , Camundongos , Músculos/patologia , Doenças Musculares/patologia
19.
Toxicon ; 22(2): 193-206, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6427978

RESUMO

Two hemorrhagic factors were isolated from the venom of Bothrops neuwiedi (jararaca pintada) by ammonium sulfate precipitation followed by chromatography on DEAE-Sephadex A-50 and DEAE-cellulose DE-32, gel filtration on Sephadex G-100 and polyacrylamide-gel electrophoresis. These factors were named neuwiedi hemorrhagic factors NHFa and NHFb. They are acidic proteins of pI 4.2-4.3 and consist of single polypeptide chains of molecular weights 46,000 and 58,000, respectively, as determined by sodium dodecyl sulfate polyacrylamide-gel electrophoresis. The hemorrhagic activity of NHFb is 23 times stronger than that of NHFa. Both hydrolyse casein, although NHFa is about 20 times more active than NHFb. They are metalloproteins inhibited by EDTA and 1,10-phenanthroline. NHFa and NHFb are serologically closely related antigens. These two factors are recognized as identical antigens by horse serum against crude Bothrops neuwiedi venom. However, the rabbit specific antiserum was able to differentiate NHFa from NHFb showing, nevertheless, that they have common determinants apart from specific determinants for each one.


Assuntos
Venenos de Crotalídeos/isolamento & purificação , Animais , Coagulação Sanguínea/efeitos dos fármacos , Hidrolases de Éster Carboxílico/análise , Caseínas , Venenos de Crotalídeos/toxicidade , Eletroforese em Gel de Poliacrilamida/métodos , Hemorragia/induzido quimicamente , Imunodifusão , Técnicas In Vitro , Focalização Isoelétrica , Peso Molecular , Peptídeo Hidrolases/análise , Proteínas/análise , Ovinos
20.
Toxicon ; 21(3): 421-7, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6353665

RESUMO

Bothrops protease A, an arginine-ester hydrolase, is active on protamine, gelatin and insulin and was isolated from the venom of Bothrops jararaca in a homogeneous state, as judged by polyacrylamide gel electrophoresis and ultracentrifugal analyses. The enzyme has a molecular weight of 65,000 and a pI of 3.55. The enzyme is a glycoprotein whose amino acid content corresponds to 55% of the molecular weight.


Assuntos
Aminoácidos/análise , Venenos de Crotalídeos/análise , Endopeptidases/análise , Serina Endopeptidases , Animais , Peso Molecular
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA