季得胜蛇药用于不明毒虫咬伤患者的疗效观察及护理

目的 观察季得胜蛇药应用于受到不明毒虫咬伤患者的效果.方法 将69例受到不明毒虫咬伤的患者随机分为实验组35例和对照组34例.实验组使用季得胜蛇药进行外敷治疗和护理,而对照组使用聚维酮碘进行涂抹,比较1周内2组的治疗效果,包括治愈率、总有效率、患者满意度以及并发症发生率.结果 治疗后,实验组的治愈率为71.43％,总有效率为97.14％,明显高于对照组的治愈率61.76和总有效率85.29％.2组在治疗期间,实验组的并发症发生率为2.86％,明显低于对照组的8.82％.而在患者对护理的满意度上,实验组的患者满意度为91.43％,显著高于对照组的85.29％.结论 季得胜蛇药治疗不明毒虫咬伤的效果更明显,且并发症发生率较低,值得在临床中推广使用.     

Management of severe musculoskeletal trauma following a dog mauling attack in a nonagenarian

Dog bites are increasingly common injuries and pose a significant public health concern. We present a case of a 92-year-old woman who sustained severe musculoskeletal trauma to the bilateral upper and lower extremities following a mauling attack by her two pet Boston Terriers. Patterns of injury and risk factors for dog bite-related injuries, as well as important clinical considerations in the medical and surgical management of dog bite injuries are discussed.     

Identification of protective B-cell epitopes of Atroxlysin-I: A metalloproteinase from Bothrops atrox snake venom

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.     

Coagulopathy after snake bite byBothrops neuwiedi: Case report and results of in vitro experiments

Summary Coagulation studies were performed in a patient who had been bitten by a snake of the speciesBothrops neuwiedi. The patient presented with hemorrhagic necrosis at the envenomization site and considerable bleeding from venous puncture sites. He developed a severe defibrination syndrome with a clottable fibrinogen level of approximately 0.1 g/l. Fibrinogen was not measurable by clotting time assay. Fibrin degradation products were greatly elevated. Treatment with antivenom caused an anaphylactic reaction within ten minutes and serum sickness after three days. In vitro experiments revealed thatB. neuwiedi venom directly activates Factors II and X, but does not activate Factor XIII. In vivo consumption of Factor XIII afterB. neuwiedi envenomization is ascribed to the action of Factor IIa. At low venom concentrations clotting is initiated by activation of prothrombin by the venom either directly or via Factor X activation. Treatment with heparin might be beneficial in coagulopathy secondary to snake bite by reducing circulating active thrombin. The venom contains thrombinlike proteases which cause slow clotting of fibrinogen, and plasmin-like components causing further proteolysis of fibrinogen and fibrin. Antivenom has no effect on the proteolytic action of the snake venom. The in vivo effects of antivenom are presumably caused by acceleration of the elimination of venom components from the circulation. Intravenous administration of antivenom caused normalization of blood coagulation parameters within 48 h.     

Snake bite induced cellulitis leading to infected open dislocation of the first metacarpophalangeal joint – A rare complication

Non-traumatic open dislocation of the first metacarpophalangeal joint is a rare phenomenon. We present a rare such occurrence secondary to snake bite induced cellulitis. A 22-year-old girl presented with pain and instability of her right thumb two months. She had snake bite two months back following which she developed cellulitis which gradually became infected. She presented with raw area over her dorsal aspect of the thumb with active infection. Radiographs revealed metacarpophalangeal joint dislocation. She underwent debridement, stabilisation and soft tissue coverage. At final follow up, she was pain free and the wound healed completely.     

2014—2018年广州周边地区圆斑蝰蛇咬伤流行病学分析

目的了解圆斑蝰蛇咬伤患者在广州周边地区的流行病学特征,为防治圆斑蝰蛇咬伤提供依据。 方法对广州医科大学附属第一医院急诊科2014年1月1日至2018年12月31日收治的圆斑蝰蛇咬伤事件的流行病学特征进行描述性分析。采用线性相关分析的方法分析咬伤后就诊时间与咬伤后出现急性肾损伤时间的相关性。 结果5年共收治毒蛇伤1481例,死亡3例,其中43例圆斑蝰蛇咬伤,死亡2例,占毒蛇伤总死亡率的66.7%（2/3）;患者分布以广州珠三角地区（肇庆、云浮、佛山、江门）伤者居多,占74.4%,9~11月是咬伤高发月份,占44.2%（19/43）,被咬伤者以农民为主,占53.5%（23/43）,50~69岁为主要高发年龄,下肢咬伤占67.4%（29/43）,蛇伤严重程度评分重度病例占74.4%（32/43）。咬伤后就诊时间与咬伤后出现急性肾损伤的时间存在显著相关性（r=0.719,P<0.01）。 结论圆斑蝰蛇咬伤是广州周边地区毒蛇伤的主要死亡原因,应对高发月份、高发地区、高发人群及高发部位进行重点监测和干预,提高公众的自我保护能力,一旦发生圆斑蝰蛇咬伤,应立即到正规医院接受针对性诊治,必要时接受血液净化治疗。     

A bite by the Twin-Barred Tree Snake,Chrysopelea pelias (Linnaeus, 1758)

Introduction.?The Twin-Barred Tree Snake, Chrysopelea pelias, is a colubrine that, like other members of the genus Chrysopelea, is able to glide in the arboreal strata. Little is known about the effects of its bite. This report is the first clinically documented bite by this relatively uncommon rear-fanged species.?Case report.?The patient was a 19-year-old female who arrived at the Emergency Department (ED) of an urban teaching hospital 6 h after being bitten by a snake that was later provisionally identified as a C. pelias. Noted on presentation were bite marks on the right middle toe with minimal inflammation and tenderness. There was slight numbness over the dorsum of the right foot and discomforting sensation radiating up the thigh that persisted for several days. There was mild pyrexia, but no evidence of any systemic effects. The full blood count did show neutrophil leucocytosis, and transient hemoglobinuria was noted in an initial urine analysis. Discussion?.?The properties of Duvernoy's secretion of C. pelias remain uncharacterized. In this case, the clinical course featured only the local effects noted above. However, the significant local pain reported by the patient suggests that bites by C. pelias are not necessarily trivial and do require full evaluation and observation in a medical facility. Discussed also is the importance of the establishment of a national registry for animal bites and stings in Malaysia.?Conclusion.?Such a facility could expedite safe and appropriate management of envenomed patients.     

Merit and Demerit of Polyvalent Snake Antivenoms

Polyvalent antivenoms contain specific antibodies capable of neutralizing a number of homologous venoms from different species/genera. They can save lives of victims of snake envenomations, even when the culprit snake has not been identified (the usual case, about 80% of the time), and a monovalent antivenom ca not be chosen. They are useful in areas where there are too many poisonous species to produce monovalent antivenoms against all of them. It is now possible to prepare polyvalent antivenoms with high potencies comparable to those of the corresponding monovalent antivenoms. With good manufacturing processes, these antivenoms have been shown to cause few and minor adverse reactions. In addition, polyvalent antivenoms exhibit a wider range of paraspecific neutralization of venoms from different species/genera, even from distant geographic areas. Lastly, it is less expensive and easier to produce and handle a few polyvalent antivenoms than batteries of monovalent antivenoms.     

Systemic and local myotoxicity induced by snake venom group II phospholipases A2: comparison between crotoxin, crotoxin B and a Lys49 PLA2 homologue.

The patterns of myotoxicity induced in mice by crotoxin, crotoxin B and a Lys49 phospholipase A(2) (PLA(2)) homologue were compared. Lys49 PLA(2)-induced local myotoxicity is reflected by creatine kinase (CK) loss in injected gastrocnemius muscle, and by a profile of CK increase in plasma characterized by a rapid increment and drop after intramuscular injection, and by a lack of CK increase in plasma after intravenous injection. In contrast, crotoxin and crotoxin B, which induce local and systemic myotoxicity, provoked a more prolonged increment in plasma CK activity upon intramuscular injection, and induced increments in plasma CK after intravenous injection. The three toxins promoted a similar extent of local myotoxicity, assessed by the loss of CK in injected gastrocnemius. A method for the quantitative assessment of the ability of toxins to induce systemic myotoxicity is proposed, based on the estimation of the ratio between the area under the curve in the plasma CK activity (total myotoxicity) to the loss of CK in injected gastrocnemius (local myotoxicity). The highest ratio corresponded to crotoxin, and the lowest corresponded to Lys49 PLA(2), the former being a systemic myotoxin and the latter a local myotoxin. Neutralization by antivenoms also differed between the toxins: a drastic reduction in plasma CK, with very poor neutralization of local CK loss, was achieved in the case of crotoxin B when antivenom was injected intravenously, whereas no neutralization was achieved in the case of Lys49 PLA(2). When tested in undifferentiated myoblasts in culture, Lys49 PLA(2) induced cytotoxicity, whereas crotoxin and crotoxin B did not, evidencing that the latter are devoid of widespread cytolytic activity. Molecular modeling analysis showed that Lys49 PLA(2) has a conspicuous cationic face, which is likely to interact with diverse membranes. In contrast, crotoxin B, despite its overall basic pI, has a lower density of positively charged residues at this molecular region. It is suggested that Lys49 PLA(2)s homologues interact, through this cationic face, with many different cell types, thus lacking specificity for muscle cells. In contrast, crotoxin B has a more selective interaction with targets in the muscle cell membrane. This selectivity might be the basis for the ability of crotoxin and crotoxin B to induce systemic myotoxicity.     

Ammodytase, a metalloprotease from Vipera ammodytes ammodytes venom, possesses strong fibrinolytic activity

Ammodytase, a high molecular mass metalloproteinase with fibrinogenolytic and fibrinolytic activities, was purified from long-nosed viper (Vipera ammodytes ammodytes) venom by gel filtration, affinity and ion-exchange chromatographies. The enzyme is a single-chain glycoprotein with apparent molecular mass of 70 kDa and isoelectric point of 6.6. Ammodytase shows very weak hemorrhagic activity, and only at doses higher than 20 μg. Consistent with this, it partially degrades some components of the extracellular matrix in vitro. It cleaves the Aα-chain of fibrinogen preferentially at peptide bonds Glu⁴⁴¹-Leu⁴⁴² and Glu⁵³⁹-Phe⁵⁴⁰. Its preference for bulky and hydrophobic amino acids at the P1′ position in substrates is demonstrated by its hydrolysis of only the Gln⁴-His⁵ and Tyr¹⁶-Leu¹⁷ bonds in the B-chain of insulin. Ammodytase is able to dissolve fibrin clots. It neither activates nor degrades plasminogen and prothrombin, and has no effect on collagen- or ADP-induced platelet aggregation in vitro. LC/MS and MS/MS analyses of its tryptic fragments demonstrated that ammodytase is a P-III class snake venom metalloproteinase composed of metalloproteinase, disintegrin-like and cysteine-rich domains. Its similarity to hemorrhagins from V. a. ammodytes venom, accompanied by very low toxicity, makes ammodytase a promising candidate as an antigen to prepare antisera against these most dangerous components of the viper's venom. Moreover, its ability to degrade fibrin clots suggests its clinical use as an antithrombotic agent.