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1.
目的探究注射用白眉蛇毒凝血酶在妇科手术中的应用疗效。方法选取本院2017年6月至2020年6月收治的50例行妇科手术的患者,按照随机数表法分为实验组与参照组,各25例。实验组术前给予注射用白眉蛇毒血凝酶2 U静脉注射,参照组给予等计量0.9%氯化钠溶液,比较两组出血时间、单位面积出血量、血红蛋白、活化部分凝血活酶时间、凝血酶原时间、凝血酶时间及空腹血糖指标。结果实验组出血时间短于参照组,单位面积出血量少于参照组,血红蛋白高于参照组,作用总有效率(96.00%)明显高于参照组(72.00%),差异有统计学意义(P<0.05);术后,实验组活化部分凝血活酶时间、凝血酶原时间、凝血酶时间及空腹血糖与术前比较差异无统计学意义。结论注射用白眉蛇毒血凝酶应用于妇科手术可减少单位面积出血量和出血时间,凝血状态差异较小,无不良反应,值得临床推广应用。  相似文献   
2.
Oral venom systems evolved multiple times in numerous vertebrates enabling the exploitation of unique predatory niches. Yet how and when they evolved remains poorly understood. Up to now, most research on venom evolution has focused strictly on the toxins. However, using toxins present in modern day animals to trace the origin of the venom system is difficult, since they tend to evolve rapidly, show complex patterns of expression, and were incorporated into the venom arsenal relatively recently. Here we focus on gene regulatory networks associated with the production of toxins in snakes, rather than the toxins themselves. We found that overall venom gland gene expression was surprisingly well conserved when compared to salivary glands of other amniotes. We characterized the “metavenom network,” a network of ∼3,000 nonsecreted housekeeping genes that are strongly coexpressed with the toxins, and are primarily involved in protein folding and modification. Conserved across amniotes, this network was coopted for venom evolution by exaptation of existing members and the recruitment of new toxin genes. For instance, starting from this common molecular foundation, Heloderma lizards, shrews, and solenodon, evolved venoms in parallel by overexpression of kallikreins, which were common in ancestral saliva and induce vasodilation when injected, causing circulatory shock. Derived venoms, such as those of snakes, incorporated novel toxins, though still rely on hypotension for prey immobilization. These similarities suggest repeated cooption of shared molecular machinery for the evolution of oral venom in mammals and reptiles, blurring the line between truly venomous animals and their ancestors.

Venoms are proteinaceous mixtures that can be traced and quantified to distinct genomic loci, providing a level of genetic tractability that is rare in other traits (14). This advantage of venom systems provides insights into processes of molecular evolution that are otherwise difficult to obtain. For example, studies in cnidarians showed that gene duplication is an effective way to increase protein dosage in tissues where different ecological roles can give rise to different patterns of gene expression (2, 5). Studies of venom in snakes have allowed comparisons of the relative importance of sequence evolution vs. gene expression evolution, as well as how a lack of genetic constraint enables diversity in complex traits (6, 7).Despite the wealth of knowledge venoms have provided about general evolutionary processes, the common molecular basis for the evolution of venom systems themselves is unknown. Even in snakes, which have perhaps the best studied venom systems, very little is known about the molecular architecture of these systems at their origin (8, 9). Using toxin families present in modern snakes to understand evolution at its origin is difficult because toxins evolve rapidly, both in terms of sequence and gene expression (10, 11). Toxins experience varying degrees of selection and drift, complicating interpretations of evolutionary models (12), and estimation of gene family evolution is often inconsistent, varying with which part of the gene (exon or intron) is used to construct the phylogeny (13). Most importantly, present-day toxins became a part of the venom over time; this diminishes their utility in trying to understand events that lead to the rise of venom systems in the nonvenomous ancestors of snakes (14, 15).A gene coexpression network aims to identify genes that interact with one another based on common expression profiles (16). Groups of coexpressed genes that have similar expression patterns across samples are identified using hierarchical clustering and are placed in gene “modules” (17). Constructing a network and comparing expression profiles of modules across taxa can identify key drivers of phenotypic change, as well as aid in identifying initial genetic targets of natural selection (18, 19). Comparative analysis using gene coexpression networks allows us to distinguish between ancient genetic modules representing core cellular processes, evolving modules that give rise to lineage-specific differences, and highly flexible modules that have evolved differently in different taxa (20). Gene coexpression networks are also widely used to construct gene regulatory networks (GRNs) owing to their reliability in capturing biologically relevant interactions between genes, as well as their high power in reproducing known protein–protein interactions (21, 22).Here we focus on gene coexpression networks involved in the production of snake venom, rather than the venom toxins themselves. Using a coexpression network we characterized the genes associated with venom production, which we term the “metavenom network,” and determine its biological role. We traced the origin of this network to the common ancestor of amniotes, which suggests that the venom system originated from a conserved gene regulatory network. The conserved nature of the metavenom network across amniotes suggests that oral venom systems started with a common gene regulatory foundation, and underwent lineage-specific changes to give rise to diverse venom systems in snakes, lizards, and even mammals.  相似文献   
3.
Background: Breast cancer is a multifactorial disease that affects women worldwide. Its progression is likely to be executed by oxidative stress wherein elevated levels of reactive oxygen and nitrogen species drive several breast cancer pathologies. Spider venom contains various pharmacological peptides which exhibit selective activity to abnormal expression of ion channels on cancer cell surface which can confer potent anti-cancer activities against this disease. Methods: Venom was extracted from a Philippine tarantula by electrostimulation and fractionated by reverse phase-high performance liquid chromatography (RP-HPLC). Venom fractions were collected and used for in vitro analyses such as cellular toxicity, morphological assessment, and oxidative stress levels. Results: The fractionation of crude spider venom generated several peaks which were predominantly detected spectrophotometrically and colorimetrically as peptides. Treatment of MCF-7 cell line of selected spider venom peptides induced production of several endogenous radicals such as hydroxyl radicals (•OH), nitric oxide radicals (•NO), superoxide anion radicals (•O2−) and lipid peroxides via malondialdehyde (MDA) reaction, which is comparable with the scavenging effects afforded by 400 µg/mL vitamin E and L-cysteine (p<0.05). Concomitantly, the free radicals produced decrease the mitochondrial membrane potential and metabolic activity as detected by rhodamine 123 and tetrazolium dye respectively (p>0.05). This is manifested by cytotoxicity in MCF-7 cells as seen by increase in membrane blebbing, cellular detachment, caspase activity and nuclear fragmentation. Conclusion: These data suggest that the Philippine tarantula venom contains peptide constituents exhibiting pro-oxidative and nitrosative-dependent cytotoxic activities against MCF-7 cells and can indicate mechanistic insights to further explore its potential application as prooxidants in cancer therapy.  相似文献   
4.
Coastal taipan (Oxyuranus scutellatus) envenoming causes life-threatening neuromuscular paralysis in humans. We studied the time period during which antivenom remains effective in preventing and arresting in vitro neuromuscular block caused by taipan venom and taipoxin. Venom showed predominant pre-synaptic neurotoxicity at 3 µg/mL and post-synaptic neurotoxicity at 10 µg/mL. Pre-synaptic neurotoxicity was prevented by addition of Australian polyvalent antivenom before the venom and taipoxin and, reversed when antivenom was added 5 min after venom and taipoxin. Antivenom only partially reversed the neurotoxicity when added 15 min after venom and had no significant effect when added 30 min after venom. In contrast, post-synaptic activity was fully reversed when antivenom was added 30 min after venom. The effect of antivenom on pre-synaptic neuromuscular block was reproduced by washing the bath at similar time intervals for 3 µg/mL, but not for 10 µg/mL. We found an approximate 10–15 min time window in which antivenom can prevent pre-synaptic neuromuscular block. This time window is likely to be longer in envenomed patients due to the delay in venom absorption. Similar effectiveness of antivenom and washing with 3 µg/mL venom suggests that antivenom most likely acts by neutralizing pre-synaptic toxins before they interfere with neurotransmission inside the motor nerve terminals.  相似文献   
5.
目的建立胶原诱导性类风湿关节炎(collagen-induced arthritis,CIA)大鼠模型来探讨胡蜂毒提取物对大鼠类风湿性关节炎(rheumatoid arthritis,RA)的治疗作用。方法将SD大鼠随机分为正常组、模型组、阳性对照组(注射用蜂毒冻干粉,1.25 mg·kg^-1)和胡蜂毒提取物低、中、高剂量(0.125、0.25、0.5 mg·kg^-1)组,除正常组外,其余各组采用多点注射鸡Ⅱ型胶原加完全弗氏佐剂的方法来诱导大鼠RA模型,每7 d一次,共14 d。造模结束后,各给药组于足趾皮下注射对应剂量的药物,连续给药14 d。分别于造模前、造模第14天和给药第14天测量大鼠踝关节直径和周长,并进行AI评分;观察大鼠脏器指数和踝关节组织HE染色的变化;采用酶联免疫吸附测定(ELISA)检测大鼠血清中相关炎症因子白细胞介素(IL)-1β、IL-6、肿瘤坏死因子(TNF)-α、IL-8、前列腺素(PG)E-2、环氧化酶(COX)-2和类风湿因子免疫球蛋白(Ig)G、Ig A、Ig M的含量变化;利用流式细胞术检测大鼠脾脏T细胞亚群的变化。结果与模型组比较,胡蜂毒提取物对CIΑ大鼠的关节肿胀(直径及周长)抑制效果显著(P<0.01),能明显降低其AI评分(P<0.01或P<0.05),能不同程度恢复大鼠的脏器指数(P<0.01或P<0.05),改善踝关节组织病理学结构病变,降低大鼠血清中各炎症因子和类风湿因子的表达(P<0.01或P<0.05),调节和改善T细胞亚群比例的紊乱(P<0.01或P<0.05)。结论胡蜂毒提取物对CIA大鼠具有较好的治疗作用,这与其对炎症细胞因子网络的调控和对免疫的调节有关系。  相似文献   
6.
蜂毒成分复杂多样,群蜂蛰伤由于大量毒液的注入,将导致人体多系统脏器功能的损伤,肾脏损伤最常见.蜂毒致急性肾损伤的主要临床表现为血红蛋白尿、少尿甚至无尿及肾功能异常,同时也可出现水、电解质及酸碱平衡的紊乱.目前蜂毒中毒尚无特异的治疗方案,除了积极的对症支持治疗外,及时的血液净化联合肾上腺素和大剂量糖皮质激素冲击治疗对于缩短患者住院时间,改善预后非常重要.免疫治疗对蜂毒过敏的患者亦是有效的治疗方案.  相似文献   
7.
8.
9.
Cancer remains one of the deadliest non-infectious diseases of the 21st century, causing millions of mortalities per year worldwide. Analyses of conventional treatments, such as radiotherapy and chemotherapy, have shown not only a lower therapeutic efficiency rate but also plethora of side-effects. Considering the desperate need to identify promising anticancer agents, researchers are in quest to design and develop new tumoricidal drugs from natural sources. Over the past few years, scorpion venoms have shown exemplary roles as pivotal anticancer agents. Scorpion venoms associated metabolites, particularly toxins demonstrated in vitro anticancer attributes against diversified cell lines by inhibiting the growth and progression of the cell cycle, inhibiting metastasis by blocking ion channels such as K+ and Cl, and/or inducing apoptosis by intrinsic and extrinsic pathways. This review sheds light not only on in vitro anticancer properties of distinct scorpion venoms and their toxins, but also on their mechanism of action for designing and developing new therapeutic drugs in future.  相似文献   
10.
《Vaccine》2016,34(14):1680-1687
Atroxlysin-I (Atr-I) is a hemorrhagic snake venom metalloproteinase (SVMP) from Bothrops atrox venom, the snake responsible for the majority of bites in the north region of South America. SVMPs like Atr-I produce toxic effects in victims including hemorrhage, inflammation, necrosis and blood coagulation deficiency. Mapping of B-cell epitopes in SVMPs might result in the identification of non-toxic molecules capable of inducing neutralizing antibodies and improving the anti-venom therapy. Here, using the SPOT-synthesis technique we identified two epitopes located in the N-ter region of Atr-I (AtrEp1—22YNGNSDKIRRRIHQM36; and AtrEp2—55GVEIWSNKDLINVQ68). Based on the sequence of AtrEp1 and AtrEp2 a third peptide named Atr-I biepitope (AtrBiEp) was designed and synthesized (23NGNSDKIRRRIH34GG55GVEIWSNKDLINVQ68). AtrBiEp was used to immunize BALB/c mice. Anti-AtrBiEp serum cross-reacted against Atr-I in western blot and was able to fully neutralize the hemorrhagic activity of Atr-I. Our results provide a rational basis for the identification of neutralizing epitopes on Atr-I snake venom toxin and show that the use of synthetic peptides could improve the generation of immuno-therapeutics.  相似文献   
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