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1.
An extensive field survey allowed us to expand the geographical distribution of the scorpion Tityus perijanensis in the Perijá range, western Zulia State, Venezuela, including areas where adult cases of severe scorpionism have been reported. 16S ribosomal RNA (rRNA) gene sequencing, DL(50) determination, and native PAGE suggest low genetic and venom proteomic divergence across the distribution range. The results also indicate phylogenetic divergence between T. perijanensis and T. discrepans, the species prevalent in northcentral Venezuela. T. perijanensis venom lethality (0.91-0.94 mg/kg) is comparable to that of the Brazilian T. serrulatus and ranks highest among toxic Venezuelan Tityus studied so far. The data indicate that the Perijá range should be included amongst the endemic areas of scorpionism of Venezuela and Colombia.  相似文献   
2.
Scorpion venoms are composed of a number of neurotoxic peptides. A variety of toxins have been isolated from the venoms of scorpions of the family Buthidae, however, little interest has been paid to non-Buthidae scorpions. In this study, we examined the toxicity of the venom of Liocheles australasiae (Hemiscorpiidae) to mice and crickets, and characterized the peptide components by HPLC and mass spectrometry. Over 200 components were detected in the L. australasiae venom by LC/MS analysis, with components of molecular masses ranging from 500 to 5000 Da being particularly abundant. A number of peptides contained two to four disulfide bridges, which was estimated based on the mass difference after derivatization of Cys residues. A peptide having a monoisotopic molecular mass of 7781.6 Da and four disulfide bridges was isolated from the venom. The peptide has a primary structure similar in terms of the position of eight Cys residues to those observed in several peptides found from scorpions, ticks and insects, although biological roles of these peptides are unknown.  相似文献   
3.
Summary A nonapeptide Thr-Ile-Ile-Asn-Val-Lys-Cys-Thr-Ser (NTX1–9) and a decapeptide Met-Asn-Gly-Lys-Cys-Lys-Cys-Tyr-Asn-Asn (NTX30–39) corresponding to the N-terminal and C-terminal sequences respectively of Noxiustoxin (NTX) were synthesized by the solid phase method of Merrifield (1963). The first synthetic peptide (NTX1–9) was shown to be toxic to mice independently of the route of administration: intraperitoneally, subcutaneously or intraventricularly (100–200 g/20 g mouse weight). The second (NTX30–39) was not toxic even at higher dose (400 g/20 g mouse). When the effects of the peptide NTX1–9 and of the authentic toxin (Noxiustoxin) were studied on the liberation of [3H] 4-aminobutyric acid (3H-GABA) from mouse synaptosomes, both gave essentially the same results, except that peptide NTX1–9 was needed at higher concentration. Synthetic peptide NTX30–39 had no effect in the same preparation at even higher doses. The GABA release produced by toxic peptide NTX1–9 was not affected by tetrodotoxin but was completely abolished by the presence of the K+ ionophore valinomycin, mimicking the effect of native NTX in the same system (Sitges et al., 1986). These results indicate that the toxic active site of Noxiustoxin is possibly located in or near the N-terminal amino acid portion of the molecule.Abbreviations used BOC amino acids ter-butyloxycarbonyl-amino acids - BOC amino acid-PAM-resin ter-butyloxycarbonyl-aminoacyl-4-(oxymethyl)-phenacetamidomethyl-resin - GABA 4 aminobutyric acid - HPLC high performance liquid chromatography - MSA mouse serum albumin - NTX Noxiustoxin - NTX (numbers) synthetic peptides with amino acid sequences of NTX at position start (first number) to position end (second number) of the sequence according to Fig. 1 - TTX tetrodotoxin Supported in part by the Mexican Council of Science and Technology (CONACyT), grants PVT/QF/NAL/84/2182, PVT/AI/NAL/85/3029 to L.D.P.; PCSACNA 022640 to A.B. A patent request claiming rights on the use of synthetic NTX and related peptides was presented in Washington, DC (U.S.A.), Serial number 07/132,169, filing date December 14, 1987.  相似文献   
4.
蝎蜂毒肽对大鼠纤溶系统作用初探   总被引:14,自引:0,他引:14  
本研究采用大鼠肢体血管灌流和整体给药两种模型,观察蝎蜂毒(SBP)对血管理灌流液内纤溶酶原激活物(PA)活性、血浆优球蛋白纤溶性(EFA)和纤溶酶(PL)活性的影响。结果说明,SBP有明显激活纤溶系统作用;其机制可能涉及血管内皮细胞释放PA活性增加,进一步促使纤溶酶原活化为PL增多的途径。  相似文献   
5.
目的探讨不同蝎毒多肽(scorpion venom peptide,SVP)组分对辐射后机体造血干细胞及祖细胞恢复的作用。方法6.0GyX射线一次性全身照射,制作辐射损伤小鼠模型。内源性脾结节法观察照射后第10天脾集落形成单位(CFU-S)的变化。用甲基纤维素半固体培养基培养骨髓混合集落生成单位(CFU-Mix),观察体内外给药方法及照射后不同时间对CFU-Mix生成的影响。结果(1)体内实验:SVPⅣ组分处理后的CFU-S数明显高于照射对照组(P<0.05);SVPⅤ组分CFU-S数量与照射对照组差异无统计学意义。照射后各SVP组CFU-Mix的数量均高于照射对照组,差异有统计学意义(P<0.05)。(2)体外实验:与照射对照组相比,体外分别单独加入SVPⅣ、Ⅴ组分以及细胞因子(IL-6和SCF)均能够促进CFU-Mix的增殖;而SVPⅣ、Ⅴ组分分别与细胞因子联合应用对CFU-Mix生成的促进作用更为明显,其中Ⅳ组分效果更强,与照射对照组相比差异均有统计学意义(P<0.05)。结论SVP具有保护辐射损伤小鼠造血干细胞及祖细胞,加速其增殖能力恢复的作用。  相似文献   
6.
Chlorotoxin, one of the key toxins in scorpion Leiurus quinquestriatus venom, has been shown to bind specifically to glioma cell surface as a specific chloride channel blocker. In this study, a purified, recombinant chlorotoxin-like peptide from the scorpion Buthus martensii Karsch (named rBmK CTa) was characterized by in vivo and in vitro studies. The results from cell proliferation assay with human glioma (SHG-44) cells showed that rBmK CTa inhibits the growth of glioma cells in a dose-dependent manner, with an IC50 value of approximately 0.28 μM. Under the same conditions, the IC50 value for normal astrocytes increased to 8 μM. This clearly indicated that rBmK CTa had specific toxicity against glioma cells but not astrocytes. Results from whole-cell patch-clamp recording showed that chloride current in SHG-44 was inhibited by rBmK CTa in a voltage-dependent manner and percent inhibitions for the blocking action of rBmK CTa (0.07 and 0.14 μM) on ICl was 17.64 ± 3.06% and 55.86 ± 2.83%, respectively. Histological analysis of rBmK CTa treated mice showed that brain, leg muscle and cardiac muscle were the target organs of this toxin. These results suggest that rBmK CTa may have potential therapeutic application in clinical treatment of human glioma. It represents an approach for developing a novel therapeutic agent.  相似文献   
7.
The present study aimed to investigate the molecular mechanism of the Astragalus–Scorpion drug pair in the treatment of prostate cancer (PCa). We employed network pharmacology and molecular docking technology to retrieving the active ingredients and corresponding targets of Astragalus–Scorpion by using TCMSP, BATMAN-TCM, TCMID and Swiss Target Prediction Databases. The targets related to PCa were retrieved through GeneCards. Cytoscape software was used to construct the ‘active ingredient–target disease’ network, and GO and KEGG enrichment analyses were performed on the common targets. Autodock software was used for molecular docking verification. In total, 26 active ingredients, 340 potential targets related to active ingredients and 122 common targets were screened from Astragalus–Scorpion drug pair. The core targets of the protein–protein interaction (PPI) network were JUN, AKT1, IL6, MAPK1 and RELA, whereas the core active ingredients were quercetin, kaempferol, formononetin, 7-o-methylisomucronulatol and calycosin. Nearly 762 GO entries and 154 pathways were obtained by using the pathway enrichment analysis. Molecular docking results revealed that quercetin and kaempferol bind to AKT1 and formononetin binds to RELA, all of which were found to be stable bounds.  相似文献   
8.
We have previously reported that in bovine adrenal chromaffin cells Ptychodiscus brevis toxin-3 (PbTx-3) does not alter the veratridine-induced 22Na influx when given alone, but increases the influx of 22Na when co-applied with either - or -scorpion venom (Wada et al. 1992). In the present study, we characterized [3H]PbTx-3 binding in bovine adrenal chromaffin cells. [3H]PbTx-3 binding was saturable, reversible and of high-affinity with an equilibrium dissociation constant (Kd) of 32.0±4.9 nmol/1 and a maximum binding capacity Bmax of 6.2 ± 1.2 pmol/4 × 106 cells (4.5 ± 0.9 pmol/mg cell protein). A Hill plot revealed the lack of cooperative interaction among the binding sites. Unlabelled PbTx-3 inhibited [3H]PbTx-3 binding with an IC50 of 31 nmol/l. However, tetrodotoxin, veratridine, - and -scorpion venom, or veratridine in combination with either - or -scorpion venom did not alter [3H]PbTx-3 binding. All these results suggest that PbTx-3 binds to a site (site 5) distinct from the previously known four toxin binding sites, which does not gate voltage-dependent Na channels by itself, but is specifically involved in the allosteric modulation of Na channels in adrenal medullary cells. Correspondence to: A. Wada at the above address  相似文献   
9.
Yellow scorpion venom is known to evoke cardiovascular responsesand cause severe myocardial damage in man. Life-threateningarrhythmias in such cases are rare. This work describes twosuch cases, and discusses the problems posed by ventriculararrhythmias in cases of scorpion sting.  相似文献   
10.
We report two children with severe neurological complications after having been stung by a scorpion. Clinical and MRI findings suggested brain infarcts. The lesions seen were in pons in one child and the right hemisphere in the other. The latter also showed possible hyperemia in the infarcted area. No vascular occlusions were observed and we therefore think the brain infarcts were a consequence of the scorpion sting. The cause of the infarct may be hypotension, shock or depressed left ventricular function, all of which are frequent in severe poisoning by scorpion sting. Received: 20 January 1999/Accepted: 13 May 1999  相似文献   
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