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1.
本文应用离子交换柱层析和凝胶过滤技术从福建产圆斑蝰蛇泰国亚种蛇毒中纯化出一个新的PLA,(PLA2-3)。经聚丙烯酰胺凝胶电泳,SDS-聚丙烯酰胺凝胶电泳和Ouchterlony双向免疫扩散证明为均一蛋白质。其理化及酶学性质如下:由约120个氨基酸残基组成(不包括半胱氨酸和色氨酸);分子量为14800;等电点为7.8;PLA2酶比活力用自动电位滴定法测定为255μmol/min·mg,用间接溶血法测定半数溶血量(HU50)在家兔和大白鼠分别为0.025μg/ml和0.05μg/ml;小鼠静脉注射的近似LD50为3154mg/kg。与从该蛇毒中分离出的毒性和碱性PLA,相比,具有PLA。酶比活力高,毒性小的特点。此酶具有明显降压作用。抗血小板聚集效应和可逆性负性心肌收缩力作用,但未观察到心肌挛缩现象.  相似文献   

2.
We studied the capacity of colloidal gold for enhancing specific and nonspecific immune response in laboratory animals (rabbits, rats, and mice) immunized with antigens of various nature. The antibody titers obtained with colloidal gold as a carrier were higher as compared to the standard immunization techniques (free antigen or its combination with Freund's adjuvant). Application of colloidal gold also enhanced nonspecific immune responses, such as lysozyme concentration in the blood, activity of the complement system proteins, as well as phagocytic and bactericidal activities. The antibodies were tested by immunodot assay using gold markers. Immunization of the animals with colloidal gold conjugates with haptens or complete antigens (without other adjuvants) was shown to induce the production of highly active antibodies. In addition, the amount of antigen used for animal immunization with colloidal gold was an order of magnitude lower, compared to immunization with complete Freund's adjuvant. This fact can be evidence for adjuvant properties of colloidal gold proper.  相似文献   

3.
This study reports a physicochemical stability evaluation of a previously reported liposomal prilocaine (PLCLUV) formulation () before and after steam sterilization as well as its local toxicity evaluation. Prilocaine (PLC) was encapsulated into extruded unilamellar liposomes (LUVs) composed by egg phosphatidylcholine:cholesterol:alfa-tocopherol (4:3:0.07, mole?%). Laser light-scattering analysis (p?>?0.05) and thiobarbituric acid reaction (p?>?0.05) were used to evaluate the liposomes physical (size) and chemical (oxidation) stability, respectively. The prilocaine chemical stability was followed by 1H-nuclear magnetic resonance. These tests detected no differences on the physicochemical stability of PLC or PLCLUV, sterilized or not, up to 30 days after preparation (p?>?0.05). Finally, the paw edema test and histological analysis of rat oral mucosa were used to assess the possible inflammatory effects of PLCLUV. PLCLUV did not evoke rat paw edema (p?>?0.05), and no significant differences were found in histological analysis, when compared to the control groups (p?>?0.05). The present work shows that PLCLUV is stable for a 30-day period and did not induce significant inflammatory effects both in the paw edema test and in histological analysis, giving supporting evidence for its safety and possible clinical use in dentistry.  相似文献   

4.
李其斌  郭鹏举  王威  宁宗  张剑锋 《蛇志》2011,23(3):232-234
目的为了探索乙醇对五步蛇毒毒性的影响。方法将五步蛇毒不同浓度致死量经不同浓度乙醇体外处理后,选择小白鼠分别给予皮下注射、口服,并将致死量蛇毒于小白鼠皮下注射后立即于局部注射乙醇,观察蛇毒毒性情况。结果使用乙醇体外处理后的五步蛇毒毒性明显下降,小白鼠经皮下注射致死量五步蛇毒后立即在局部注射50%异蛇米酒或75%乙醇0.1~0.2ml有一定的保护作用,口服20倍致死量五步蛇毒未发现有毒性表现。结论五步蛇毒体外经过乙醇处理后毒性明显下降。口服五步蛇毒是安全的。蛇毒进入皮下后立即用乙醇处理有一定的治疗效果。  相似文献   

5.
目的为了探索乙醇对眼镜蛇毒毒性的影响。方法将眼镜蛇毒不同浓度致死量经不同浓度乙醇体外处理后,分别于小白鼠皮下注射、口服,将致死量蛇毒皮下注射后的小白鼠立即于局部注射乙醇,观察蛇毒毒性情况。结果小白鼠经皮下注射致死量眼镜蛇毒后,在局部注射50%(或异蛇米酒)、75%乙醇0.1~0.2ml有一定的保护作用;口服100倍皮下注射致死量眼镜蛇毒未发现有毒性表现,口服经50%乙醇处理后的眼镜蛇毒(100倍皮下注射致死量)未增加小鼠死亡率。结论眼镜蛇毒体外经过乙醇处理后毒性有所下降。口服少量的眼镜蛇毒是安全的。眼镜蛇毒与乙醇混合后口服未见蛇毒毒性增加。  相似文献   

6.
Abstract

Cytochrome c oxidase, the terminal electron acceptor of the respiratory chain of mitochondria, is an integral membrane protein. The bioenergetic properties of cytochrome oxidase can be studied only when the macromolecule is inserted in a phospholipid bilayer, either in situ or after reconstitution into liposomal membranes. Reintegration of purified cytochrome oxidase in liposomes allows quantitative tests of mechanistic hypothesis concerning the functional properties of the enzyme. Small unilamellar vesicles are prepared by sonication of purified soybean asolectin, and reconstitution of cytochrome oxidase in the bilayer is carried out according to the cholate/dialysis procedure. The proteoliposomes are shown to mimick the mitochondrial state of the enzyme in so far as liposomal cytochrome oxidase : a) displays the same vectorial orientation, the cytochrome c binding site being externally exposed, b) pumps protons in the physiological inside/outside direction, and c) is functionally controlled by the transmembrane electrochemical gradient, i.e. displays respiratory control.  相似文献   

7.
Preparations of phosphodiesterase from Vipera lebetina venom immobilized on agarose were obtained. The kinetic properties for the hydrolyses of various substrates of soluble and immobilized phosphodiesterase, e. g. effects of pH, temperature, substrate concentrations, etc., were compared. The values of Km, V and activation energy for the substrate hydrolyses were determined.  相似文献   

8.
蛇毒心脏毒素对动物细胞的遗传损伤和生殖毒性研究   总被引:1,自引:0,他引:1  
梁敏仪  管锦霞 《蛇志》1998,10(1):7-10
目的 应用眼镜蛇毒心脏毒素(CTX)作用于小鼠的骨髓细胞和生殖细胞,以探讨CTX对动物体的生殖毒性和遗传毒性。方法 对小鼠腹腔注射不同剂量CTX,通过生殖毒性实验和致突变实验,分析孕鼠的胚胎存活率,骨髓细胞和精母细胞的染色体畸变率。结果:CTX能影响胎鼠的生长发育,使孕鼠的增重和活胎率均明显地降低(P〈0.001),染色体畸变实验显示CTX0.4mg/kg剂量上精母细胞多倍体和非整倍体细胞数目增高  相似文献   

9.

Background

Previously, we have reported that most, if not all, of the Scyphozoan jellyfish venoms contain multiple components of metalloproteinases, which apparently linked to the venom toxicity. Further, it is also well known that there is a positive correlation between the inflammatory reaction of dermal tissues and their tissue metalloproteinase activity. Based on these, the use of metalloproteinase inhibitors appears to be a promising therapeutic alternative for the treatment of jellyfish envenomation.

Methodology and Principal Findings

Tetracycline (a metalloproteinase inhibitor) has been examined for its activity to reduce or prevent the dermal toxicity induced by Nemopilema nomurai (Scyphozoa: Rhizostomeae) jellyfish venom (NnV) using in vitro and in vivo models. HaCaT (human keratinocyte) and NIH3T3 (mouse fibroblast) incubated with NnV showed decreases in cell viability, which is associated with the inductions of metalloproteinase-2 and -9. This result suggests that the use of metalloproteinase inhibitors, such as tetracycline, may prevent the jellyfish venom-mediated local tissue damage. In vivo experiments showed that comparing with NnV-alone treatment, tetracycline pre-mixed NnV demonstrated a significantly reduced progression of dermal toxicity upon the inoculation onto rabbit skin.

Conclusions/Significance

It is believed that there has been no previous report on the therapeutic agent of synthetic chemical origin for the treatment of jellyfish venom-induced dermonecrosis based on understanding its mechanism of action except the use of antivenom treatment. Furthermore, the current study, for the first time, has proposed a novel mechanism-based therapeutic intervention for skin damages caused by jellyfish stings.  相似文献   

10.
It was found that dihydroquercetin, a flavonoid of plant origin, localized in lecitin nanoparticles with glycine amino acid, reduced inflammatory reactions in wound zones after thermal burns. The application of the liposomal complex to burn trauma stabilized the endogenous antioxidant system and minimized the area of secondary necrosis in the wound. The intensification of skin regeneration and repair of hair follicles and sebaceous glands were also observed.  相似文献   

11.
12.
王立兰  田霖 《蛇志》1995,7(1):4-6
使用不同稀释度的蛇毒毒素,等体积注射于大鼠背部皮下、皮内和小鼠背部皮下,18~24小时剥皮观察比较动物皮下出血程度,经统计学处理,小鼠背部皮下注射对检查出血毒最敏感。选用小鼠背部皮下注射0.2u蛇毒酶成品、半成品,18~24小时剥皮观察皮下瘀血或瘀斑,发现42批成品中88.1%未见皮下瘀血,24批半成品75%未见皮下瘀血。说明选用小鼠背部皮下注射0.2u蛇毒酶来限量检查出血毒的方法是可取的。  相似文献   

13.
14.
Snake venom serine proteinases (SVSPs) affect various physiological functions including blood coagulation, fibrinolysis, and platelet aggregation. Coagulant serine proteinase (VLCII) was purified from Vipera lebetina venom using three chromatographic steps: gel filtration on SephadexG‐75, DEAE‐Sephadex A‐50, and reversed‐phase high‐performance liquid chromatography (RP‐HPLC) on C8 column. VLCII appeared homogenous (60 kDa) when tested on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS‐PAGE). VLCII as a thrombin‐like enzyme was able to hydrolyze Nα‐CBZ L‐arginine‐p‐nitroanilide hydrochloride and could be a serine protease because it is inhibited by phenylmethylsulfonyl fluoride. The proteolytic activity of VLCII was not affected by ethylenediaminetetraacetic acid and 1.10‐phenanthroline. It showed high coagulant activity against human plasma and cleaved both Aα chain and Bβ chain of bovine fibrinogen. The isolated VLCII displayed proaggregating effect on human platelet in a concentration‐dependent manner with an absence of lag time. Clopidogrel P2Y12 adenosine diphosphate (ADP) receptor inhibitor reduced markedly the aggregating effect induced by VLCII than aspirin, indicating the involvement of ADP signaling pathway.  相似文献   

15.
A solubilized sheep red blood cell (SRBC) antigen (supernatant fraction obtained by centrifuging 107-2 × 108 sonicated SRBC at 6 × 104 g for 30 min [Sup-SRBC]), whose ability to inhibit anti-SRBC plaque formation was 70% of that of the original sonicated SRBC, was unable to elicit a detectable antibody response in either unprimed or SRBC-primed mice. However, Sup-SRBC as well as intact SRBC antigens generated memory for the secondary response, which was transferable to irradiated syngeneic recipients by injection of immune spleen cells. The memory generated by Sup-SRBC involved helper memory for anti-trinitrophenyl group (TNP) response to challenge with TNP-conjugated SRBC. Increase in the helper T cell memory in the spleens of Sup-SRBC-primed mice was also demonstrated by an in vitro culture experiment and by an adoptive cell transfer experiment. In contrast, no detectable B cell memory was generated by Sup-SRBC. Repeated stimulation with Sup-SRBC never induced significant antibody response but reduced the level of memory. A single injection of a low dose (106) of SRBC also failed to induce a definite primary antibody response generating memory for the secondary response. However, repeated stimulation with this dose of SRBC induced a high antibody response and generated good memory. From these results it is suggested that the intact structure of SRBC is required for the activation of B cells, but is not necessary for the stimulation of T cells.  相似文献   

16.
The influence of cholesterol (Chol) in the liposomal bilayer on the properties of inhalable protein-loaded liposomal powders prepared by spray-drying technique was investigated. Lysozyme (LSZ) was used as a model protein. Feed solution for spray drying was prepared by direct mixing of aqueous solution of LSZ with mannitol solution and empty liposome dispersions composed of hydrogenated phosphatidylcholine and Chol at various molar ratios. The spray-dried powders were characterized with respect to morphology, thermal property, and crystallinity using scanning electron microscopy, differential scanning calorimetry, and X-ray diffraction, respectively. Most formulations gave slightly aggregated, spherical particles, and percentage yields of the spray-dried powders decreased with increasing Chol content. Degree of particle aggregation depended on the powder composition. The powders spontaneously formed liposomes which efficiently entrapped LSZ after reconstitution with HEPES buffered saline (HBS) at 37°C. Lysozyme entrapment efficiency and size distribution of the reconstituted liposomes were evaluated after the powders were reconstituted with HBS. Increasing Chol content resulted in a decrease in size of the reconstituted liposomes and an increase in entrapment efficiency of LSZ. These results correlated with thermal behaviors of the reconstituted liposomes. Biological activity of LSZ was not affected by the spray-drying process. It was also demonstrated that LSZ-loaded liposomal powders could be produced without the need to preload the LSZ into liposomes prior to spray-drying process.  相似文献   

17.
18.
The kallikrein inhibitor-peptide content of Tityus serrulatus scorpion crude venom was purified by Sephadex G-50 and Sephadex G-25 fine gel filtration chromatographies, followed by two steps of reverse-phase column on HPLC. The isolated inhibitor peptide was homogeneous in its N-terminal and partial amino acid sequence, showing a molecular weight of 4.489 Da by mass spectrometry and amino acid analysis. The peptide was tested with rat plasma and urine kallikrein, which resulting in an inhibition with similar afinity to both enzymes, showing an IC50 of 14.3 μM after 13 and 8 min, respectively, using kininogen as substrate on the isolated guinea-pig ileum bioassay. The porcine pancreatic kallikrein showed after 10 min an IC50 value of 12.6 μM with H-D-Val-Leu-Arg-pNA HCl as substrate. In addition, the isolated peptide significantly inhibited porcine pancreatic kallikrein with values in the range of apparent or absolute calculated peptide K i = 2.5 μM. The inhibitor was heat resistant and stable at pH values less than 5.  相似文献   

19.
王志清  庄茂辛 《蛇志》1999,11(4):12-17
目的 从广西产中华眼镜蛇毒 ( N aja naja atra)中分离了一种新的磷脂酶 A2 ( PLA2 ) ,并研究其性质。 方法 磷脂酶 A2 ( PLA2 )的分离纯化采用 CM5 2、CM-Sepharose CL-6 B离子交换柱和 SepharoseCL-6 B凝胶柱 ,磷脂酶 A2 ( PLA2 )的性质采用经典方法进行。 结果 分离后的磷脂酶 A2 经过聚丙烯酰胺凝胶电泳、SDS-聚丙烯酰胺凝胶电泳和 HPLC检测 ,其为单一组分。SDS-PAGE测定它的分子量为1 5 0 0 0± 1 0 0 0。等电聚焦测得它的等电点为 6 .3。它的最适温度为 5 5℃ ,最适 p H值为 8.5。氨基酸成分分析表明该酶由 1 2 6个氨基酸组成 ,以 Asp、Ala、Gly、Cys居多。Fe3 、Zn2 、EDTA对其酶活力起抑制作用 ;K 、Ca2 、去垢剂对其活力起促进作用。荧光光谱分析表明该酶的色氨酸残基、组氨酸残基可能位于分子表面。药理实验表明 :该酶具有抗胰蛋白酶作用、抗凝血作用、间接溶血作用以及对青蛙具有心脏毒性。 结论 广西产中华眼镜蛇毒磷脂酶 A2 与其它来源的 PLA2 同源性高 ,但性质不尽相同。  相似文献   

20.
The seeds of the almond tree [(Prunus dulcis (Mill.) D. A. Webb. (syn. Prunus amygdalus)] were collected in two different periods of maturity and were studied for their lipid content. The total lipids (TL) were extracted by the Bligh-Dyer method and the lipid classes have been isolated by chromatographic techniques and were analyzed by HPTLC coupled with a flame ionization detector (HPTLC/FID) and GC-MS. The oils were found to be rich in neutral lipids (89.9% and 96.3% of total lipids) and low in polar lipids (10.1% and 3.7% of total lipids) for the immature and mature seed oils, respectively. The neutral lipid fraction consisted mainly of triacylglycerides whereas the polar lipids mainly consisted of phospholipids. GC-MS data showed that the main fatty acid for both oils was 9-octadecenoic acid (oleic acid). The unsaturated fatty acids were found as high as 89.4% and 89.7%, while the percentage of the saturated fatty acids was found 10.6% and 10.3% for the immature and mature seed oils, respectively. Liposomes were prepared from the isolated phospholipids using the thin lipid film methodology, and their physical properties were characterized. Cytotoxicity was found absent when assayed against normal and cancerous cell lines. These new formulations may have future applications for encapsulation and delivery of drugs and cosmetically active ingredients.  相似文献   

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