RESUMEN
OBJECTIVE@#To investigate the inhibitory effect of agkistrodon halys venom antitumor component-I (AHVAC-I) on vasculogenic mimicry (VM) formation in triple-negative breast cancer MDA-MB-231 cells and explore its possible mechanism.@*METHODS@#CCK8 assay was used to determine the optimal concentration of AHVAC-I for cell treatment based on its halfinhibitory concentration (IC50). MDA-MB-231 cells were treated with different concentrations of AHVAC-I or 5-Fu, and the changes in vasomimetic capacity of the cells were examined using Matrigel assay. The expression levels of matrix metalloproteinase-2 (MMP2) and MMP9 in the treated cells were detected using quantitative PCR and Western blotting.@*RESULTS@#Compared with the control treatment with culture medium, treatment with 5, 10 and 20 μg/mL AHVAC-I significantly reduced vasomimetic ability of MDA-MB-231 cells in a dose-dependent manner (P < 0.01). MMP2 supplementation obviously restored the vasomimetic ability of the cells inhibited by AHVAC-I.@*CONCLUSION@#AHVAC-I inhibits VM formation in triplenegative breast cancer cells in vitro by down-regulating MMP2 production.
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Animales , Humanos , Agkistrodon/metabolismo , Línea Celular Tumoral , Esperanza de Vida Saludable , Metaloproteinasa 2 de la Matriz/metabolismo , Neovascularización Patológica/metabolismo , Neoplasias de la Mama Triple Negativas/metabolismo , PonzoñasRESUMEN
BACKGROUND: Agkistrodon acutus, a traditional Chinese medicine, clinically used in the treatment of rheumatism, tumor, and cardiovascular and cerebrovascular diseases. Due to the unique medicinal value and the difficulty of artificial breeding of Agkistrodon acutus, the supply of Agkistrodon acutus on the market exceeds the demand, and a large number of its adulterants are found on the market. In this study, the cytb gene sequences of Agkistrodon acutus and 9 snakes were compared and analyzed, specific primers were designed, and specific PCR methods were established to detect Agkistrodon acutus medicinal samples on the market. RESULTS: This method was successfully applied to distinguish the snake from other adulterated species, and tested 18 Agkistrodon acutus samples randomly purchased from six cities. Twelve samples were counterfeit and six were genuine. The standard reference material of Agkistrodon acutus was cloned by molecular cloning and sequencing, and the gene sequence difference with other species was significant. It shows that the region could be used as the fingerprint region of the target species. CONCLUSIONS: The proposed method can be used as a species-specific marker and can be highly distinguished from other adulterated snake species, which is helpful to effectively avoid the problem of false sale of Agkistrodon acutus.
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Animales , Reacción en Cadena de la Polimerasa/métodos , Agkistrodon/genética , Citocromos b/genética , Mitocondrias/genética , Serpientes , Especificidad de la Especie , ADN/análisis , Clonación Molecular , Medicina Tradicional ChinaRESUMEN
Agkistrodon acutus is a traditional Chinese herb medicine which has immunological regulation,anti-tumor,anti-inflammatory and analgesic effects,which is mainly used for the treatment of rheumatoid arthritis,ankylosing spondylitis,sjogren's syndrome and tumors. In order to excavate more important functional genes from A. acutus,the transcriptome of the venom gland was sequenced by the Illumina Hi Seq 4000,and 32 862 unigenes were assembled. Among them,26 589 unigenes were mapped to least one public database. 2 695 unigenes were annotated and assigned to 62 TF families,and 5 920 SSR loci were identified. The majority of mapped unigenes was from Protobothrops mucrosquamatus in the NR database,which revealed their closest homology. Three secretory phospholipase A_2 with different amino acid sequences showed similar spatial structures and all had well-conserved active sites. The 3 D structural models of C-type lectin showed conserved glycosylation binding sites( Asn45). This study will lay the foundation for the further study of the function of snake venom protein,and promoting the development and utilization of genome resources from A. acutus.
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Animales , Agkistrodon/genética , Venenos de Crotálidos , Perfilación de la Expresión Génica , Venenos de Serpiente/genética , Serpientes , TranscriptomaRESUMEN
El presente trabajo muestra una experimentación pura basada en la preparación homeopática del veneno de la serpiente Agkistrodon bilineatus, algo que ha demostrado su eficacia en diferentes aplicaciones clínicas que datan de la época de Constantine Hering, uno de los pioneros de la Homeopatía en Estados Unidos. Los resultados son alentadores, toda vez que los órganos con mayor número y diversidad de síntomas fueron el sistema nervioso central, los ojos, así como los aparatos respiratorio y digestivo. En conclusión, este derivado del veneno de la serpiente en referencia, preparado homeopáticamente, puede emplearse debido a que se generó una patogenesia concreta en un grupo de experimentadores.
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Humanos , Masculino , Femenino , Materia Medica , Método Hahnemanniano , Semiología Homeopática , Agkistrodon , Prácticas ClínicasRESUMEN
<p><b>OBJECTIVE</b>To determine the effective dosage and formulation of agkistrodon in collagen-induced arthritis (CIA) rats.</p><p><b>METHODS</b>CIA was induced by injection of collagen in complete/incomplete Freund's adjuvant. Agkistrodon decoction, agkistrodon powder, and agkistrodon wine were administered daily starting from the onset of arthritis. Paw swelling degree was measured by using a volume-measuring instrument every 7 days after primary immunization. Arthritis index was measured and calculated using the "five scoring method" every 7 days. The levels of serum interleukin-1ß (IL-1ß) and type II collagen IgG antibodies were detected by enzyme-linked immunosorbent assay. Finally, all ankles were removed, and X-ray radiography was performed with In-vivo Imaging System FX. Samples were counterstained with hematoxylin and eosin for analysis.</p><p><b>RESULTS</b>Among the various dosage formulations of agkistrodon, high-dose powder, which was equivalent to an amount of 6 g/day in adults, showed better effects on the inhibition of joint swelling and reduction of arthritis index score. The relatively low levels of serum IL-1 and anti-type II collagen IgG antibodies, as well as the X-ray radiography and pathology results, further proved the superiority of the high-dose powder over the other formulations. The effect of decoction on inhibiting joint swelling was inversely proportional to the dosage. Other effects, such as reduction of arthritis index score and the levels of serum IL-1 and anti-type II collagen IgG antibodies, were directly proportional to the dosage. While the use of large dose agkistrodon wine led to negative effects.</p><p><b>CONCLUSION</b>These data highlight the potential function of high-dose agkistrodon powder, which was equivalent to an amount of 6 g/day in adults. The powder can quickly relieve the symptoms of rheumatoid arthritis and prevent aggravation of disease, especially during the early period.</p>
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Animales , Femenino , Agkistrodon , Metabolismo , Anticuerpos , Sangre , Artritis Experimental , Sangre , Quimioterapia , Colágeno Tipo II , Alergia e Inmunología , Formas de Dosificación , Relación Dosis-Respuesta a Droga , Ensayo de Inmunoadsorción Enzimática , Extremidades , Diagnóstico por Imagen , Patología , Interleucina-1beta , Sangre , Medicina Tradicional China , Ratas WistarRESUMEN
Human sparganosis is a zoonotic disease caused by infection with larval forms (procercoid/plerocercoid) of Spirometra spp. The purpose of this study was to identify Spirometra spp. of infected snakes using a multiplex PCR assay and phylogenetic analysis of mitochondrial DNA sequence data from the spargana of terrestrial snakes obtained from Korea and China. A total of 283 snakes were obtained that included 4 species of Colubridae comprising Rhabdophis tigrinus tigrinus (n=150), Dinodon rufozonatum rufozonatum (n=64), Elaphe davidi (n=2), and Elaphe schrenkii (n=7), and 1 species of Viperidae, Agkistrodon saxatilis (n=60). The snakes were collected from the provinces of Chungbuk, Chungnam, and Gyeongbuk in Korea (n=161), and from China (n=122). The overall infection rate with spargana was 83% (235/283). The highest was recorded for D. rufozonatum rufozonatum (100%), followed by A. saxatilis (85%) and R. tigrinus tigrinus (80%), with a negative result for E. davidi (0%) and E. schrenkii (0%). The sequence identities between the spargana from snakes (n=50) and Spirometra erinaceieuropaei (KJ599680) or S. decipiens (KJ599679) control specimens were 90.8% and 99.2%, respectively. Pairwise genetic distances between spargana (n=50) and S. decipiens ranged from 0.0080 to 0.0107, while those between spargana and S. erinaceieuropaei ranged from 0.1070 to 0.1096. In this study, all of the 904 spargana analyzed were identified as S. decipiens either by a multiplex PCR assay (n=854) or mitochondrial cox1 sequence analysis (n=50).
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Humanos , Agkistrodon , China , Colubridae , ADN Mitocondrial , Corea (Geográfico) , Reacción en Cadena de la Polimerasa Multiplex , Análisis de Secuencia , Serpientes , Esparganosis , Plerocercoide , Spirometra , Viperidae , ZoonosisRESUMEN
This study was purpose to investigate apoptosis pathway of leukemia K562 cells induced by anticoagulant fraction from Agkistrodon acutus venom (AVVC-1). The mitochondrial transmembrane potential (ΔΨm) of leukemia K562 cells was detected by flow cytometry with JC-1 single staining. The expression of cytochrome C in the mitochondrial of leukemia K562 cells was analyzed by Western blot after AVVC-1 treatment. The distribution of cytochrome C in leukemia K562 cells was measured by immuno-fluorescence test. The results showed that the potential of mitochondrial membrane decreased after treatment with different concentrations of AVVC-1 (12.5, 25, 50, 100 µg/ml) for 6 h (P < 0.01). The expression level of cytochrome C protein in mitochondria obviously declined after treatment with 30 µg/ml AVVC-1 for 48 h, and the fluorescent intensity of cytochrome C in cytosol was enhanced at the same time. It is concluded that AVVC-1-induced K562 cell apoptosis is related with mitochondrial damage, and cytochrome C may be a useful agent for investigating human leukemia therapy by using AVVC-1.
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Animales , Humanos , Agkistrodon , Apoptosis , Citocromos c , Metabolismo , Células K562 , Potencial de la Membrana Mitocondrial , Mitocondrias , Metabolismo , Venenos de Serpiente , FarmacologíaRESUMEN
The object of the research was to extract, purify and identify the type II collagen of Agkistrodon acutus. Type II collagen of A. acutus was extracted by enzyme decomposition method, and purified by ion exchange column chromatography. It was characterized by SDS-PAGE gel electrophoresis, ultraviolet spectrophotometry, infrared absorption spectroscopy and mass spectroscopy. The results showed that the size of C II was about 130 kDa. It absorbed at 223 nm. IR spectrum obtained showed that the triple helical domains of amino-acid sequences were characterized by the repetition of triplets Gly-X-Y. The MS spectrum graphically stated that C II extracted from cow and A. acutus have the similar peptides. The C II of A. acutus was obtained by extraction and purification. Appraisal analysis by SDS-PAGE, UV, IR and MS, C II of A. acutus was consistent with the standard C II of cow. It was proved that the extracted protein was C II.
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Animales , Agkistrodon , Metabolismo , Colágeno Tipo II , Química , Metabolismo , Electroforesis en Gel de Poliacrilamida , Espectrometría de Masas , Proteínas de Reptiles , Química , MetabolismoRESUMEN
The properties and agglutination activity of acutolysin C, a hemorrhagic metalloproteinase obtained from Agkistrodon acutus venom, were studied herein. Acutolysin C is a basic glycoprotein consisting of a single polypeptide chain with a molecular weight of 23.1 kDa and pI 8.7, containing one Zn2+ and one Ca2+ per molecule. It possesses caseinolytic, weak lethal (LD50 = 7.6 mg/kg) and weak hemorrhagic (MHD = 12.0 µg) activities, but does not present fibrinolytic, fibrinogenolytic, arginine esterase and phospholipase A2 actions. In addition, it revealed agglutination activity on some animal lymphocytes, including five species of mammals, six of birds, three of reptiles and one of amphibians, but had no effect on lymphocytes from two species of reptiles, one amphibian and nine species of fish. It had no effects on the erythrocytes and platelets of all 26 animal species tested. Both leucoagglutination and caseinolytic activities were inhibited by EDTA; while cysteine, 2-mercaptoethanol, 1,4-dithiothreitol, glutathione, serum against acutolysin C and serum against homologous snake venom as well as glucose, sucrose, mannose, lactose and galactose had no effects on inhibition. The lowest concentration of acutolysin C that induced mouse lymphocyte agglutination was 2.5 µg/mL. Acutolysin C is an interesting substance since it is the first member of the hemorrhagin family to be shown to have leucoagglutination activity. (AU)
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Venenos de Serpiente , Agkistrodon , Aglutinación , Metaloproteasas , HemorragiaRESUMEN
<p><b>BACKGROUND</b>Hemocoagulase Agkistrodon for injection is a single component thrombin which has passed phases I and II clinical trials. The purpose of this phase III clinical trial was to evaluate the effect of Hemocoagulase Agkistrodon on hemostasis and coagulation in abdominal skin and subcutaneous incisions and to assess the safety of this agent in surgical patients.</p><p><b>METHODS</b>This is a phase III, prospective, randomized, double-blind, and controlled multicenter clinical trial including 432 consecutive patients randomized into either a study group (injected with hemocoagulase Agkistrodon at 2 U, n = 324) or a control group (injected with hemocoagulase Atrox, n = 108). The hemostatic time, hemorrhagic volume, hemorrhagic volume per unit area, blood coagulation, and adverse events were measured and compared between the two groups.</p><p><b>RESULTS</b>The mean hemostatic time in the study group was (36.8 +/- 18.7) seconds; the hemorrhagic volume was (3.77 +/- 3.93) g; and the hemorrhagic volume per unit area was (0.091 +/- 0.125) g/cm(2). In the control group, the corresponding values were (38.1 +/- 19.7) seconds, (4.00 +/- 4.75) g, and (0.095 +/- 0.101) g/cm(2), respectively. No significant difference in values existed between the two groups (P > 0.05). Blood coagulation results and hepatic and renal function were also similar between the two groups. Adverse events were reported in two cases, but were deemed non-drug-related.</p><p><b>CONCLUSIONS</b>Hemocoagulase Agkistrodon has good hemostatic and coagulative function and is safe for the use of arresting capillary hemorrhage that occurs while incising the abdomen during surgery.</p>
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Adolescente , Adulto , Anciano , Animales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Abdomen , Cirugía General , Agkistrodon , Batroxobina , Farmacología , Coagulación Sanguínea , Método Doble Ciego , Medicina Basada en la Evidencia , Hemostasis , Hemostáticos , Farmacología , Estudios ProspectivosRESUMEN
An anticoagulant factor was purified from the venom of the Iranian snake Agkistrodon halys by gel filtration on Sephadex G-50 and ion-exchange chromatography on DEAE-Sepharose. In the final stage of purification, the percentage recovery of purified anticoagulant factor was found to be 83 percent. The purified anticoagulant factor revealed a single protein band in SDS-polyacrylamide electrophoresis under reducing conditions and its molecular weight was about 22 kDa. The purified peptide did not show any effect on casein, BApNA or plasma.(AU)
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Animales , Cromatografía por Intercambio Iónico , Agkistrodon , Venenos de Crotálidos/toxicidad , Anticoagulantes/aislamiento & purificaciónRESUMEN
<p><b>BACKGROUND</b>Snake venom contains a number of components with different pharmacological and biological activities, especially in cancer therapy, and has increasingly become a research focus. This study was designed to isolate and purify a novel anti-clotting protein component from the venom of Agkistrodon acutus, and to explore its physico-chemical properties and biological activity.</p><p><b>METHODS</b>The venom of Agkistrodon was isolated and purified by ion-exchange chromatography on diethylaminoethyl (DEAE)-Sepharose Fast Flow, molecular sieve filtration through Sephadex G75, SP-Sepharose Fast Flow and molecular sieve filtration through Sephadex G50. We detected the activated partial thromboplastin time (APTT) of the eluant to select the anti-clotting protein component of interest. The molecular weight was determined by sodium dodecyl sulfate-polyacrylamid gel electrphoresis (SDS-PAGE) and liquid chromatography. Its protein content was detected by bicinchoninic acid (BCA).</p><p><b>RESULTS</b>SDS-PAGE vertical gel electrophoresis showed that the anticoagulant factor is a tripolymer composed of three proteins whose molecular weights are 25 KDa, 30 KDa and 50 KDa. The factor contains about 65% percent protein.</p><p><b>CONCLUSIONS</b>A novel anti-clotting protein component was purified by ion-exchange chromatography and molecular sieve filtration from the venom of Agkistrodon acutus and was found to be composed of three kinds of proteins.</p>
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Animales , Agkistrodon , Metabolismo , Anticoagulantes , Química , Cromatografía Líquida de Alta Presión , Cromatografía por Intercambio Iónico , Venenos de Crotálidos , Química , Electroforesis en Gel de Poliacrilamida , Proteínas , QuímicaRESUMEN
Thrombin-like enzymes (TLEs) are studied widely because of their therapeutic potential in myocardial infarction and thrombotic diseases. We synthesized the DNA fragment encoding thrombin-like enzyme calobin from Agkistrodon caliginosus (Korean Viper) venom by fusion PCR and expressed it in Pichia pastoris. After induction by 0.5% methanol for 48 h, the expression level of recombinant calobin reached 3.5 g/L in medium. The recombinant calobin was purified by Q-Sepharose Fast Flow ion-exchange chromatography and Sephacryl-S-100 gel filtration chromatography. Purified sample had a molecular weight of 32 kD shown in SDS-PAGE. It hydrolyzed fibrinogen and formed a light white hydrolysis circle in fibrinogen plate. SDS-PAGE analysis showed that recombinant calobin cleaved Aalpha-chain of fibrinogen specifically, and produced an appropriately 40 kD new band. However, we failed to find its fibrin-clot formation activity.
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Animales , Agkistrodon , Pichia , Genética , Metabolismo , Proteínas Recombinantes , Genética , Serina Endopeptidasas , Genética , Trombina , Genética , Venenos de VíborasRESUMEN
Agkistrodon halys is one of several dangerous snake species in Iran. Among the most important signs and symptoms in patients envenomated by this snake is disseminated intravascular coagulation. A thrombin-like enzyme, called AH143, was isolated from Agkistrodon halys venom by gel filtration on a Sephadex G-50 column, ion-exchange chromatography on a DEAE-Sepharose and high performance liquid chromatography (HPLC) on a C18 column. In the final stage of purification, 0.82 mg of purified enzyme was obtained from 182.5 mg of venom. The purified enzyme showed a single protein band by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), under reducing conditions, and its molecular mass was found to be about 30 kDa. AH143 revealed clotting activity in human plasma, which was not inhibited by EDTA or heparin. This enzyme still demonstrated coagulation activity when exposed to variations in temperature and pH ranging, respectively, from 30 to 40°C and from 7.0 to 8.0. It also displayed proteolytic activities on synthetic substrate. The purified enzyme did not show any effect on casein. We concluded that the venom of the Iranian snake Agkistrodon halys contains about 0.45 percent single procoagulant protein which appears to be a thrombin-like enzyme.(AU)
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Animales , Dodecil Sulfato de Sodio , Cromatografía por Intercambio Iónico , Agkistrodon , Serina ProteasasRESUMEN
This study was aimed to investigate the hemostatic effects of hemocoagulase agkistrodon (HCA) and its mechanism. The procoagulative and hemostatic effects of HCA were evaluated by using rabbit blood coagulatin time and mouse tail bleeding time; the mechanisms of HCA hemostatic effect were analyzed by using rabbit blood clot lysis and fibrinogen lysis. The results showed that HCA shortened the rabbit blood coagulation time and the mouse tail bleeding time significantly. The effects are nearly similar to that of positive control (reptilase). HCA also induced rabbit blood clot lysis and directly hydrolysed the alpha-chain of fibrinogen. It is concluded that HCA exert its hemostatic effects by hydrolysing the alpha-chain of fibrinogen, but it is not able to induce production of XIII factor.
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Animales , Ratones , Conejos , Agkistrodon , Batroxobina , Farmacología , Tiempo de Sangría , Coagulación Sanguínea , Venenos de Crotálidos , Fibrinógeno , Metabolismo , Hemostáticos , Farmacología , Distribución AleatoriaRESUMEN
The study was purposed to investigate the effect of extract of Agkistrodon Halys venom on proliferation and apoptosis of K562 cells. The inhibition of K562 cell proliferation was measured by MTT assay; The morphologic changes of K562 cells was observed by microscopy; the apoptosis of K562 cells was measured by flow cytometry; the activity of extracellular signal-regulated kinase (ERK) in K562 cells was detected by Western blot. The results showed that when K562 cells were treated with 0, 1, 10, 20 microg/ml of the extraction for 48 hours, the apoptosis rates were 2.1%, 21.3%, 49.7%, 70.1%, respectively. The proliferation of K562 cells was obviously inhibited in dose-dependent manner. Typical morphologic changes significantly appeared in the extract-treated K562 cells. The extract obviously inhibited the activity of ERK in K562 cells. It is concluded that the extract of Agkistrodon Halys' venom can inhibit the proliferation of K562 cells and induce apoptosis of K562 cells.
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Animales , Humanos , Agkistrodon , Apoptosis , Proliferación Celular , Mezclas Complejas , Farmacología , Venenos de Crotálidos , Química , Quinasas MAP Reguladas por Señal Extracelular , Metabolismo , Células K562RESUMEN
Agkistrodon contortrix laticinctus myotoxin (ACLMT) is a myotoxic Lys49 phospholipase A2 isolated from the venom of the broad-banded copperhead, A. c. laticinctus. We have previously shown that ACLMT affects water transport in toad bladders, but little in known about the mechanisms involved in the action of this toxin on membrane permeability. In this study, we examined the morphological alterations caused by ACLMT in toad bladder epithelium. The bladders were exposed to the toxin (20 nM) for 30 min at 23o C using Bentleys technique. Longitudinal and cross sections were obtained from paraffin-embedded bladders and stained with hematoxylin-eosin prior to analysis by light microscopy. Exposure to the toxin resulted in disorganization of the epithelial cell layer and damage to the smooth muscle bundles. The smooth muscle cells were swollen, with hypercontracted myofi laments and clear areas among the fibers. These findings suggest that ACLMT affects the structural integrity of the epithelium, and that the pathological changes induced by this toxin in smooth muscle cells may be caused by an increase in the cytosolic calcium concentration. These results contribute to our understanding of the mechanisms involved in the action of snake venom Lys49 PLA2 myotoxins in biological tissues.
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Animales , Agkistrodon , Venenos de Crotálidos , Células Epiteliales , Miocitos del Músculo Liso , Fosfolipasas A , Vejiga Urinaria , Anuros , EpitelioRESUMEN
<p><b>OBJECTIVE</b>To evaluate the efficacy and safety of hemocoagulase acutus for injection and determine its curative dose.</p><p><b>METHODS</b>Forty-five patients on abdominal surgeries were randomly allocated into 2 study groups and 1 control group. Thirty minutes before the operation, the patients in the study groups received intravenous hemocoagulase acutus at 1 U and 2 U, respectively, and control group had no treatment. The hemostatic time, hemorrhagic volume, and hemoagglutination were observed in all the groups.</p><p><b>RESULTS</b>The average hemorrhagic volume and hemorrhagic volume per square were significantly lower in the two study groups than in the control group (P<0.05), and the average hemorrhagic volume per square were significantly lower in study group 2 U than in the 1 U group (P<0.05). No significant differences were found in adverse effects between the 3 groups.</p><p><b>CONCLUSION</b>Hemocoagulase acutus for injection has good hemostatic effect for controlling capillary hemorrhage at the abdominal incisions and can be safely used in the surgical patients.</p>
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Adolescente , Adulto , Anciano , Animales , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Abdomen , Cirugía General , Agkistrodon , Metabolismo , Batroxobina , Usos Terapéuticos , Coagulación Sanguínea , Pérdida de Sangre Quirúrgica , Hemostasis Quirúrgica , Métodos , Hemostáticos , Usos Terapéuticos , Inyecciones Intravenosas , Resultado del TratamientoRESUMEN
A novel serine protease with high purity was extracted from the venom of Agkistrodon hlays Pallas using monoclonal antibody affinity chromatography. This protease releases bradykinin and has arginine esterase activity without being activated. After purification, its hydrolytic activity exceeded 800 U/mg, far higher than its counterparts from mammalian sources. The purity of the kininogenase could exceed 95%. The acute toxicity and the long-term toxicity of this kallikrein was studied for its potential clinical application. The maximum tolerance dose in adult was 150,000 times greater than the maximum applied dose, and long-term administration at the dose 50 times of allowed clinical dose did not obviously after the animals' body weight, survival condition, liver function, renal function, or blood routines, suggesting the extremely low toxicity of the kallidrein.