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Sarah Weissenberg - One of the best experts on this subject based on the ideXlab platform.
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inhibition of the proteolytic activity of hemorrhagin e from crotalus atrox venom by antihemorrhagins from homologous serum
Toxicon, 1992Co-Authors: Sarah Weissenberg, Michael Ovadia, Elazar KochvaAbstract:Abstract Antihemorrhagic proteins from Crotalus atrox serum were tested for their ability to inhibit the proteolytic activity of the hemorrhagic toxin-e from Crotalus atrox venom and of several other proteolytic enzymes: trypsin, collagenase and thermolysin. The Antihemorrhagic proteins inhibited the proteolytic activity of hemorrhagin-e when tested on gelatin type I and collagen type IV, the proteolytic activity of trypsin on photofilm gelatin and the proteolytic activity of whole venom when tested on azocollagen and photofilm gelatin. The antihemorrhagins failed to inhibit the proteolytic activity of trypsin when tested on the specific synthetic substrate N-acetyl- dl -phenylalanine-β-naphthyl ester (APNE), the activity of microbial collagenase on N-(3-[2-furyl]acryloyl)-Leu-Gly-Pro-Ala (FALGPA) or on azocollagen and the activity of thermolysin on N-(3-[2-furyl] acryloyl)-Gly-Leu amide (FAGLA). It is tentatively suggested that the antihemorrhagins from snake blood serum are proteinase inhibitors that under-went specialization towards the neutralization of the proteolytic activity of hemorrhagic toxins.
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Antihemorrhagic factors from the blood serum of the western diamondback rattlesnake crotalus atrox
Toxicon, 1991Co-Authors: Sarah Weissenberg, Michael Ovadia, Gideon Fleminger, Elazar KochvaAbstract:Abstract Several Antihemorrhagic factors isolated from C. atrox serum are glycoproteins with mol. wt ranging from 65,000 to 80,000. The Antihemorrhagic activity of these factors was stable at a pH range of 1.3–11.5 and at temperatures up to 85°C, for 30 min. The isolated antihemorrhagins also neutralized the proteolytic activity of C. atrox venom, as tested with azocollagen and gelatin, and formed a complex with hemorrhagic toxin e isolated from the same venom. The neutralization capacity of the isolated antihemorrhagins was six times as high as the commercial polyvalent antivenom produced for clinical use.
Elazar Kochva - One of the best experts on this subject based on the ideXlab platform.
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inhibition of the proteolytic activity of hemorrhagin e from crotalus atrox venom by antihemorrhagins from homologous serum
Toxicon, 1992Co-Authors: Sarah Weissenberg, Michael Ovadia, Elazar KochvaAbstract:Abstract Antihemorrhagic proteins from Crotalus atrox serum were tested for their ability to inhibit the proteolytic activity of the hemorrhagic toxin-e from Crotalus atrox venom and of several other proteolytic enzymes: trypsin, collagenase and thermolysin. The Antihemorrhagic proteins inhibited the proteolytic activity of hemorrhagin-e when tested on gelatin type I and collagen type IV, the proteolytic activity of trypsin on photofilm gelatin and the proteolytic activity of whole venom when tested on azocollagen and photofilm gelatin. The antihemorrhagins failed to inhibit the proteolytic activity of trypsin when tested on the specific synthetic substrate N-acetyl- dl -phenylalanine-β-naphthyl ester (APNE), the activity of microbial collagenase on N-(3-[2-furyl]acryloyl)-Leu-Gly-Pro-Ala (FALGPA) or on azocollagen and the activity of thermolysin on N-(3-[2-furyl] acryloyl)-Gly-Leu amide (FAGLA). It is tentatively suggested that the antihemorrhagins from snake blood serum are proteinase inhibitors that under-went specialization towards the neutralization of the proteolytic activity of hemorrhagic toxins.
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Antihemorrhagic factors from the blood serum of the western diamondback rattlesnake crotalus atrox
Toxicon, 1991Co-Authors: Sarah Weissenberg, Michael Ovadia, Gideon Fleminger, Elazar KochvaAbstract:Abstract Several Antihemorrhagic factors isolated from C. atrox serum are glycoproteins with mol. wt ranging from 65,000 to 80,000. The Antihemorrhagic activity of these factors was stable at a pH range of 1.3–11.5 and at temperatures up to 85°C, for 30 min. The isolated antihemorrhagins also neutralized the proteolytic activity of C. atrox venom, as tested with azocollagen and gelatin, and formed a complex with hemorrhagic toxin e isolated from the same venom. The neutralization capacity of the isolated antihemorrhagins was six times as high as the commercial polyvalent antivenom produced for clinical use.
John C. Perez - One of the best experts on this subject based on the ideXlab platform.
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Resistance of warm-blooded animals to snake venoms.
Toxicon, 2002Co-Authors: John C. Perez, Vivian E Garcia, Willis C. Haws, Bruce M. JenningsAbstract:Abstract Crotalus atrox venom resistance in 40 species of animal sera was studied by means of Antihemorrhagic assay, ring precipitation test and serum protection test. The Antihemorrhagic titers ranged from 0 to 256 with 16 animal sera having a titer greater than two. Five animal sera precipitated with C. atrox venom and the titers ranged from 0 to 64. Procyon lotor (racoon), Liomys irroratus (Mexican spiny pocket mouse) and two species of Peromyscus sp. (white footed deer mouse) were the only unimmunized animals with both a positive Antihemorrhagic and ring precipitation titer. One of the resistant sera, Neotoma micropus (gray woodrat), was further studied to determine effects of five other snake venoms. Neotoma micropus serum neutralized hemorrhagic factors in all hemorrhagic venoms tested but would not neutralize the lethal factors of elapid venoms in the serum protection test. It appears that both reptiles and warm-blooded animals have Antihemorrhagic factors in their sera.
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Comparative study on hemorrhagic and proteolytic activities of snake venoms.
Toxicon, 2002Co-Authors: Shyi Yi Huang, John C. PerezAbstract:Abstract The hemorrhagic and proteolytic titers of nine snake venoms were measured. Suitable venom dilutions were selected to study the Antihemorrhagic and antiproteolytic activities of three warm-blooded animal sera — gray woodrat (Neotoma micropus), hispidus cottonrat (Sigmodon hispidus) and Virginia opossum (Didelphis virginiana). It was demonstrated that all hemorrhagic venoms are proteolytic. The results show that the hemorrhagic activity of the venoms is readily neutralized by the sera; however, the proteolytic activity is not neutralized. We suggest that the mechanisms involved in neutralizing the two activities are not closely related.
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the effects of western diamondback rattlesnake crotalus atrox venom on the production of antihemorrhagins and or antibodies in the virginia opossum didelphis virginiana
Toxicon, 2002Co-Authors: Morgan R Mckeller, John C. PerezAbstract:Abstract Opossums are animals that are naturally resistant to the proteolytic effects of Crotalid venoms. Opossums possess proteinase inhibitors in their sera that bind to and neutralize hemorrhagic and other proteolytic activity in many snake venoms. The proteinase inhibitors are not antibodies since they have different molecular weights (60 kDa) and pI (4.2). The purpose of this study was to determine if opossums were capable of producing antibodies against venom and/or increasing the production of proteinase inhibitors (specifically antihemorrhagins). Five different venom immunization protocols were used to determine the effects of the venom in the opossums. The dosages ranged from 1 mg of venom per immunization to 350 mg/kg body weight of venom per immunization. The Antihemorrhagic response was increased, but there is no evidence to suggest that an opossum can produce antibodies against venom. The lack of an antibody response is most likely due to the natural proteinase inhibitors clearing the venom from the opossum's body before an antibody response can occur.
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the Antihemorrhagic factor of the mexican ground squirrel spermophilus mexicanus
Toxicon, 1999Co-Authors: R R Martinez, John C. Perez, Elda E Sanchez, R CamposAbstract:Abstract The Mexican ground squirrel ( Spermophilus mexicanus ) has a natural resistance to western diamondback rattlesnake venom ( Crotalus atrox ). The LD 50 for the Mexican ground squirrel is 53 mg/kg body weight, which is 13 times higher than that of BALB/c mice. An Antihemorrhagic factor from serum of the Mexican ground squirrel was isolated using Sephadex G-200 gel filtration, ion exchange A-50, G-75 gel filtration and HPLC DEAE 5PW ion exchange chromatography. The purified factor neutralized proteolytic and hemorrhagic activity of crude C. atrox venom. The results of this research suggest that the Antihemorrhagic factor in the serum of the Mexican ground squirrel is not an antibody and neutralizes hemorrhagic activity of C. atrox venom.
Tamotsu Omorisatoh - One of the best experts on this subject based on the ideXlab platform.
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the Antihemorrhagic factor erinacin from the european hedgehog erinaceus europaeus a metalloprotease inhibitor of large molecular size possessing ficolin opsonin p35 lectin domains
Toxicon, 2000Co-Authors: Tamotsu Omorisatoh, Yoshio Yamakawa, Dietrich MebsAbstract:Abstract From muscle extracts of the European hedgehog, Erinaceus europaeus , an Antihemorrhagic factor, erinacin, was purified by ammonium sulfate precipitation followed by chromatography on DEAE-cellulose, hydroxylapatite and gel filtration columns. A purification of approx. 1400-fold was achieved with an overall yield of 21% in Antihemorrhagic activity. The molecular weight of erinacin determined by gel filtration was approx. 1000 kDa. SDS-PAGE of erinacin under reducing conditions indicates that it consists of two types of subunits, α and β , with molecular weights of 37 and 35 kDa, respectively, in a ratio of 1:2. In the presence of 6 M guanidine–HCl, erinacin dissociates into α -subunits and β -subunit decamers. From these results the subunit assembling of erinacin has been formulated as α 10 ·2 β 10 . The molecular weight of the subunits and of the β -subunit decamer was confirmed by MALDI-TOF mass spectrometry. Erinacin inhibits the hemorrhagic and proteolytic activity of the major hemorrhagic metalloprotease from the venom of Bothrops jararaca . Complete inhibition was achieved in an equimolar mixture of inhibitor and enzyme suggesting an equimolar complex. Erinacin is not inhibiting serine proteases such as trypsin and chymotrypsin, it was characterized to be a metalloprotease inhibitor. In electronmicroscopy, flower bouquet-like structures characteristic for some animal lectins were observed. Amino acid sequence analysis indicated that both subunits are almost identical and are composed of common amino terminal, collagen- and fibrinogen-like domains homologous to proteins of the ficolin/opsonin P35 lectin family.
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comparison of Antihemorrhagic activities in skeletal muscle extracts from various animals against bothrops jararaca snake venom
Toxicon, 1998Co-Authors: Tamotsu Omorisatoh, Motohide Takahashi, Yoshiaki Nagaoka, Dietrich MebsAbstract:Abstract T. Omori-Satoh, M. Takahashi, Y. Nagaoka and D. Mebs. Comparison of Antihemorrhagic activities in skeletal muscle extracts from various animals against Bothrops jararaca snake venom. Toxicon 36, 421–423, 1998.—Antihemorrhagic activities of skeletal muscle extracts from various animals were compared in inhibiting the hemorrhagic activity of Bothrops jararaca venom. The muscle extracts of the European hedgehog (Erinaceus europaeus) exhibited the strongest activity, followed by those of other insectivores such as the shrew (Crocidura russula) and mole (Talpa europaea). The Antihemorrhagic activities of muscle extracts from experimental animals such as mice, rats, guinea-pigs, hamsters and rabbits were negligible.
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inhibition of hemorrhagic activities of various snake venoms by purified Antihemorrhagic factor obtained from japanese habu snake
Toxicon, 1994Co-Authors: Tamotsu Omorisatoh, Yoshiaki Nagaoka, Yoshio Yamakawa, Dietrich MebsAbstract:Abstract T. Omori-Satoh , Y. Nagaoka , Y. Yamakawa and D. Mebs . Inhibition of hemorrhagic activities of various snake venoms by purified Antihemorrhagic factor obtained from Japanese Habu snake. Toxicon32, 365–368, 1994.—The ability of purified Antihemorrhagic factor isolated from the serum of Japanese Habu (Trimeresurus flavoviridis) was tested on 17 snake venoms to inhibit their hemorrhagic activity. The factor strongly inhibited that of the venoms of Crotalus horridus horridus and Vipera latastei gaditana in addition to that of the homologous (T. flavoviridis) venom. Hemorrhagic activity of Agkistrodon halys blomhoffi, Agkistrodon contortrix contortrix, Bothrops atrox asper and Crotalus atrox venoms was also remarkably inhibited, but that of Vipera mauretanica to less extent. The hemorrhagic activities of nine other snake venoms were not inhibited.
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primary structure of the Antihemorrhagic factor in serum of the japanese habu a snake venom metalloproteinase inhibitor with a double headed cystatin domain
Journal of Biochemistry, 1992Co-Authors: Yoshio Yamakawa, Tamotsu OmorisatohAbstract:: The complete amino acid sequence of an Antihemorrhagic factor, HSF, in the serum of the Japanese Habu snake, Trimeresurus flavoviridis, has been determined. The protein is composed of 323 amino acid residues and contains three asparagine-linked oligosaccharide chains at positions 123, 185, and 263. The molecule contains two copies of the cystatin domain in the N-terminal portion up to position 240, and these domains show a remarkable sequence homology (about 50%) to those of plasma glycoproteins such as alpha 2-HS (human) and fetuin (bovine) and to a lesser extent to that of HRG (human). The amino acid sequence of the noncystatin region towards the C-terminus is unique, showing no significant homology with those of the corresponding regions of alpha 2-HS and fetuin. In spite of the presence of cystatin domains, HSF does not inhibit cysteine proteinases such as papain and cathepsin B but does inhibit several metalloproteases in Habu venom. The results suggest that HSF is the first protein found to be functionally related to metalloproteinase inhibitors among the structurally homologous proteins with a double-headed cystatin domain, and is a member of a novel family (family 4) with divergent functions of the cystatin superfamily proteinase inhibitors. Although HSF possesses similar physicochemical properties to those of oprin, a snake venom metalloproteinase inhibitor with Antihemorrhagic activity isolated from opossum serum [Catanese & Kress (1992) Biochemistry 31, 410-418], its primary structure is strikingly different from that of oprin.
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an improved method for purifying Antihemorrhagic factor in the serum of habu snake trimeresurus flavoviridis
Journal of Biochemistry, 1991Co-Authors: Yoshio Yamakawa, Tamotsu OmorisatohAbstract:: A new method is presented for purifying Antihemorrhagic factor in the serum of Japanese Habu snake (Trimeresurus flavoviridis). The method consists of specific binding of the factor to a hemorrhagic principle-conjugated Sepharose, gel filtration and reverse-phase HPLC. The improved method is simple and rapid, providing the factor with a great increase in specific activity and in a high yield.
Dietrich Mebs - One of the best experts on this subject based on the ideXlab platform.
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the Antihemorrhagic factor erinacin from the european hedgehog erinaceus europaeus a metalloprotease inhibitor of large molecular size possessing ficolin opsonin p35 lectin domains
Toxicon, 2000Co-Authors: Tamotsu Omorisatoh, Yoshio Yamakawa, Dietrich MebsAbstract:Abstract From muscle extracts of the European hedgehog, Erinaceus europaeus , an Antihemorrhagic factor, erinacin, was purified by ammonium sulfate precipitation followed by chromatography on DEAE-cellulose, hydroxylapatite and gel filtration columns. A purification of approx. 1400-fold was achieved with an overall yield of 21% in Antihemorrhagic activity. The molecular weight of erinacin determined by gel filtration was approx. 1000 kDa. SDS-PAGE of erinacin under reducing conditions indicates that it consists of two types of subunits, α and β , with molecular weights of 37 and 35 kDa, respectively, in a ratio of 1:2. In the presence of 6 M guanidine–HCl, erinacin dissociates into α -subunits and β -subunit decamers. From these results the subunit assembling of erinacin has been formulated as α 10 ·2 β 10 . The molecular weight of the subunits and of the β -subunit decamer was confirmed by MALDI-TOF mass spectrometry. Erinacin inhibits the hemorrhagic and proteolytic activity of the major hemorrhagic metalloprotease from the venom of Bothrops jararaca . Complete inhibition was achieved in an equimolar mixture of inhibitor and enzyme suggesting an equimolar complex. Erinacin is not inhibiting serine proteases such as trypsin and chymotrypsin, it was characterized to be a metalloprotease inhibitor. In electronmicroscopy, flower bouquet-like structures characteristic for some animal lectins were observed. Amino acid sequence analysis indicated that both subunits are almost identical and are composed of common amino terminal, collagen- and fibrinogen-like domains homologous to proteins of the ficolin/opsonin P35 lectin family.
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comparison of Antihemorrhagic activities in skeletal muscle extracts from various animals against bothrops jararaca snake venom
Toxicon, 1998Co-Authors: Tamotsu Omorisatoh, Motohide Takahashi, Yoshiaki Nagaoka, Dietrich MebsAbstract:Abstract T. Omori-Satoh, M. Takahashi, Y. Nagaoka and D. Mebs. Comparison of Antihemorrhagic activities in skeletal muscle extracts from various animals against Bothrops jararaca snake venom. Toxicon 36, 421–423, 1998.—Antihemorrhagic activities of skeletal muscle extracts from various animals were compared in inhibiting the hemorrhagic activity of Bothrops jararaca venom. The muscle extracts of the European hedgehog (Erinaceus europaeus) exhibited the strongest activity, followed by those of other insectivores such as the shrew (Crocidura russula) and mole (Talpa europaea). The Antihemorrhagic activities of muscle extracts from experimental animals such as mice, rats, guinea-pigs, hamsters and rabbits were negligible.
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Muscle extract of hedgehog, Erinaceus europaeus, inhibits hemorrhagic activity of snake venoms
Toxicon, 1994Co-Authors: Tamotsu Omori-satoh, Yoshiaki Nagaoka, Dietrich MebsAbstract:Abstract The Antihemorrhagic activity of muscle extract of hedgehog, Erinaceus europaeus, was tested on various snake venoms with hemorrhagic activity. The extract inhibited strongly hemorrhagic activity of venoms from Bitis arietans, Bothrops jararaca and Vipera latastei gaditana, and remarkably that of venoms from Agkistrodon halys blomhoffi, Bitis gabonica rhinoceros, Bitis nasicornis, Bothrops atrox asper, Crotalus horridus horridus and Vipera berus. The Antihemorrhagic activity against eight other snake venoms was below the detection level.
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inhibition of hemorrhagic activities of various snake venoms by purified Antihemorrhagic factor obtained from japanese habu snake
Toxicon, 1994Co-Authors: Tamotsu Omorisatoh, Yoshiaki Nagaoka, Yoshio Yamakawa, Dietrich MebsAbstract:Abstract T. Omori-Satoh , Y. Nagaoka , Y. Yamakawa and D. Mebs . Inhibition of hemorrhagic activities of various snake venoms by purified Antihemorrhagic factor obtained from Japanese Habu snake. Toxicon32, 365–368, 1994.—The ability of purified Antihemorrhagic factor isolated from the serum of Japanese Habu (Trimeresurus flavoviridis) was tested on 17 snake venoms to inhibit their hemorrhagic activity. The factor strongly inhibited that of the venoms of Crotalus horridus horridus and Vipera latastei gaditana in addition to that of the homologous (T. flavoviridis) venom. Hemorrhagic activity of Agkistrodon halys blomhoffi, Agkistrodon contortrix contortrix, Bothrops atrox asper and Crotalus atrox venoms was also remarkably inhibited, but that of Vipera mauretanica to less extent. The hemorrhagic activities of nine other snake venoms were not inhibited.
