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1.
A large number of humans are stung by jellyfish all over the world. The stings cause acute pain followed by persistent pain and local inflammation. Harmful jellyfish species typically cause strong pain, whereas harmless jellyfish cause subtle or no pain. Jellyfish sting humans by injecting a tubule, contained in the nematocyst, the stinging organ of jellyfish. The tubule penetrates into the skin leading to venom injection. The detailed morphology of the nematocyst tubule and molecular structure of the venom in the nematocyst has been reported; however, the mechanism responsible for the difference in pain that is caused by harmful and harmless jellyfish sting has not yet been explored or explained. Therefore, we hypothesized that differences in the length of the nematocyst tubule leads to different degrees of epithelial damage. The initial acute pain might be generated by penetration of the tubule, which stimulates pain receptor neurons, whilst persistent pain might be caused by injection of venom into the epithelium. To test this hypothesis we compared the lengths of discharged nematocyst tubules from harmful and harmless jellyfish species and evaluated their ability to penetrate human skin. The results showed that the harmful jellyfish species, Chrysaora pacifica, Carybdea brevipedalia, and Chironex yamaguchii, causing moderate to severe pain, have nematocyst tubules longer than 200 μm, compared with a jellyfish species that cause little or no pain, Aurelia aurita. The majority of the tubules of harmful jellyfishes, C. yamaguchii and C. brevipedalia, were sufficiently long to penetrate the human epidermis and physically stimulate the free nerve endings of Aδ pain receptor fibers around plexuses to cause acute pain and inject the venom into the human skin epithelium to cause persistent pain and inflammation.  相似文献   

2.

Background

Massive wasp stings have been greatly underestimated and have not been systematically studied. The aim of this study was to identify the clinical features and treatment strategies of severe wasp stings.

Methods and Findings

A multicenter retrospective study was undertaken in 35 hospitals and medical centers including 12 tertiary care hospitals and 23 secondary care hospitals in the Hubei Province, China. The detailed clinical data of 1091 hospitalized wasp sting patients were investigated. Over three-fourths (76.9%) of the cases had 10 or more stings and the in-hospital mortality of patients was 5.1%. Forty-eight patients died of organ injury following toxic reactions to the stings, whereas six died from anaphylactic shock. The in-hospital mortality in patients with >10 stings was higher than that of ≤10 stings (5.2% vs. 1.0%, p = 0.02). Acute kidney injury (AKI) was seen in 21.0% patients and most patients required blood purification therapy. Rhabdomyolysis was seen in 24.1% patients, hemolysis in 19.2% patients, liver injury in 30.1% patients, and coagulopathy in 22.5% patients. Regression analysis revealed that high creatinine level, shock, oliguria, and anemia were risk factors for death. Blood purification therapy was beneficial for patients with ≥20 stings and delayed hospital admission of patients (≥4 hours after sting).

Conclusions

In China, most patients with multiple wasp stings presented with toxic reactions and multiple organ dysfunction caused by the venom rather than an anaphylactic reaction. AKI is the prominent clinical manifestation of wasp stings with toxic reaction. High creatinine levels, shock, oliguria, and anemia were risk factors for death.  相似文献   

3.
Problems with food allergy and other adverse reactions to food are still a challenge for science. Both, in case of diagnostic and therapy and in characterization of allergens there is still a lot to do in research to help the continuously increasing number of allergic patients. But an exact elucidation of allergen structure, the development of hypoallergenic food by gentechnological processing of allergenic proteins, a better therapy, the knowledge of the pathogenetic effect or a complete declaration of ingredients in prepacked foods will never lead to absolutely sure food for allergic patients. As the pathogenesis, the symptoms, and sensibilization individually differ, at least for every allergic patient there will remain a risk.  相似文献   

4.
Macrocentrus grandii is a polyembryonic parasitoid, with embryos that divide asexually within the host (European corn borer, Ostrinia nubilalis) to produce broods of clonal offspring. From a biological control standpoint, polyembryony seems advantageous because each parasitized host yields multiple parasitoids with minimal time and egg investment. When we observed M. grandii in the field, however, we found that the parasitoid virtually always invested additional time and, if possible, stings into hosts that it had already stung, apparently reducing some of the advantages of polyembryony. We therefore investigated and found support for two potential benefits that can be gained by self-superparasitism in this system. First, multiple stings allowed production of mixed-sex broods: 27% of multiply-stung versus 0% of singly-stung hosts produced mixed-sex broods. Second, multiple stings increased mean parasitoid progeny produced per host, primarily by reducing the chance of complete brood failure. Our results indicate substantial benefit for a second sting, but little benefit for three or more stings, even though M. grandii was sometimes observed to invest more than two stings within a single host. However, we also found that within-host larval competition is prevalent, suggesting that supernumerary stings may pay off in competition against conspecific larvae. Such additional investment within a single host would be particularly beneficial when hosts, rather than eggs, are limiting, but would decrease the overall efficacy of M. grandii as a biological control agent.  相似文献   

5.
Jellyfish tentacles in contact with human skin can produce pain swelling and redness. The pain is due to discharge of jellyfish nematocysts and associated toxins and discharge can be caused by a variety of mechanical and chemical stimuli. A series of tests were carried out with chemicals traditionally used to treat jellyfish stings e.g. acetic acid ammonia meat tenderizer baking soda and urea to determine if these chemicals stimulated or inhibited nematocyst discharge and if they brought relief to testers who were exposed to jellyfish tentacles. Chrysaora quinquecirrha (sea nettle) Chiropsalmus quadrumanus (sea wasp) and Physalia physalis (Portuguese man-of-war) were used in the study. It was found that many of the chemicals traditionally used to treat jellyfish stings stimulated nematocyst discharge and did not relieve the pain. However there was immediate relief when a common anesthetic lidocaine was sprayed on the skin of testers in contact with jellyfish tentacles. Initial exposure of tentacle suspensions to lidocaine prevented the nematocyst discharge by subsequent exposure to acetic acid ethanol ammonia or bromelain. Thus lidocaine in addition to acting as an anesthetic on skin in contact with jellyfish tentacles inhibited nematocyst discharge possibly by blocking sodium and/or calcium channels of the nematocytes.  相似文献   

6.
Hymenoptera stings can cause serious injury to humans. We report the clinical findings of 6 cases of Hymenoptera stings. All patients developed painful erythematous papules at the sting sites and had a past history of parasitoid wasp sting. This is the first clinical report of the parasitoid wasp, Cephalonomia gallicola, causing human stings in Korea.  相似文献   

7.
Allergenic tropomyosins and their cross-reactivities   总被引:1,自引:0,他引:1  
The ingestion or inhalation of some proteins may lead to adverse immune reactions. Allergens may trigger allergic reactions in genetically predisposed individuals when they are absorbed through the skin or make contact with mucous membranes. An allergic disease often deteriorates the quality of life and may sometimes be life-threatening due to anaphylactic shock. A number of allergens have been characterized from various multicellular organisms to date. It is thought to be reasonable to pay a special attention to the substance which is highly cross-reactive and which causes adverse responses in the molecules that are not sensitized but similar to the sensitized allergen. Tropomyosin has been described as an important food allergen in shrimp, lobster, crab, oysters, squid, and other invertebrates. Allergic reactions to shellfish and mollusks are often cross-reactive, which may be explained by the highly conserved amino acid sequences of tropomyosins among invertebrates, but vertebrate tropomyosins are not known to be allergenic. Several tropomyosins from domestic arthropods have been reported to be allergenic. Recently, it was suggested that an infection of helminthic parasites might lead to sensitization to tropomyosin and elicit allergic reactions to other invertebrates. Much effort has been made to characterize these allergenic tropomyosins from various sources. We will discuss the physicochemical characteristics and the potential application of tropomyosin for the diagnosis and therapeutics of allergic disorders.  相似文献   

8.
7起乙型脑炎疫苗异常反应的调查和分析   总被引:1,自引:0,他引:1  
对1993~1997年间因接种乙脑疫苗引起的7起异常反应进行了调查和分析,主要是Ⅰ型变态反应(0.33%~1.6%)和心因性反应(11.7%~24.2%)。反应一般发生在第3针以后,有些发生在第6针。症状表现为过敏性休克、紫癜、荨麻疹、血管神经性水肿、气喘等。对变态反应的发生频率、反应机理、处理方法和预防等问题进行了讨论  相似文献   

9.
The phyllosoma, a larva of spiny and slipper lobsters, has an exceptionally flat body and long appendages. It is known to associate with several species of cnidarian jellyfish, a behavior that is not rare in crustaceans. Indeed, phyllosomas clinging onto jellyfish have been observed both in the laboratory and in the natural environment. Wild phyllosomas have been found to contain jellyfish tissues in their hepatopancreas and feces, suggesting that the larvae utilize jellyfish as a food source; however, how they capture jellyfish and what species of jellyfish they prefer have rarely been investigated. The few previous studies conducted have suggested that phyllosomas have a high specificity for jellyfish (preying on only a few species); in contrast, the results of our study indicate that specificity is low. We show that phyllosomas prey on a variety of jellyfish species including deadly stinging types, on a variety of jellyfish developmental stages, and on various parts of the jellyfish body. When making contact with a jellyfish, phyllosomas first cling onto its exumbrella, feed on its tentacles or oral arms, and then consume the exumbrella. Phyllosomas may be capable of defending themselves against any types of nematocyst sting, and it is likely that they have evolved to utilize venomous jellyfish as a food in the open sea, where food may be scarce.  相似文献   

10.
J H Toogood 《CMAJ》1987,136(9):929-933
Beta-blocker therapy is associated with an increase in the severity and, possibly, the incidence of acute anaphylaxis. The population at risk consists of people with allergic conditions who are given a beta-blocker for an unrelated condition. Anaphylaxis under these conditions may be severe, protracted and resistant to conventional treatment because of the beta-adrenergic blockade. Severe or fatal attacks have been triggered by insect stings, the ingestion of allergenic foods or drugs, and injections of radiocontrast media, antisera or immunotherapy antigens. These occurrences are probably infrequent, but their incidence is unknown. At least two fatal cases have recently occurred in Canada. Clinical allergists, internists and family practitioners in particular should be aware of the need for aggressive and prolonged support in patients who experience anaphylaxis while receiving beta-blocker therapy and should report all such occurrences to the federal registry of adverse drug reactions. Allergy skin testing or immunotherapy is inadvisable in patients who take a beta-blocker orally or in the form of ophthalmic eyedrops. The list of relative contraindications to beta-blocker use should be extended to include susceptibility to recurrent anaphylaxis, whether it is idiopathic or due to an identifiable cause.  相似文献   

11.
Chironex fleckeri (Australian box jellyfish) stings can cause acute cardiovascular collapse and death. We developed methods to recover venom with high specific activity, and evaluated the effects of both total venom and constituent porins at doses equivalent to lethal envenomation. Marked potassium release occurred within 5 min and hemolysis within 20 min in human red blood cells (RBC) exposed to venom or purified venom porin. Electron microscopy revealed abundant ∼12-nm transmembrane pores in RBC exposed to purified venom porins. C57BL/6 mice injected with venom showed rapid decline in ejection fraction with progression to electromechanical dissociation and electrocardiographic findings consistent with acute hyperkalemia. Recognizing that porin assembly can be inhibited by zinc, we found that zinc gluconate inhibited potassium efflux from RBC exposed to total venom or purified porin, and prolonged survival time in mice following venom injection. These findings suggest that hyperkalemia is the critical event following Chironex fleckeri envenomation and that rapid administration of zinc could be life saving in human sting victims.  相似文献   

12.
Medusae play an important role in marine ecosystems, as competitors of many invertebrate and fish species. Additionally, jellyfish stings can cause severe pain, inflammation of the affected skin, and allergic reactions in human. Climate and environmental changes are likely to affect the medusae, but it is not yet clear whether these will affect their distribution, physiology, and their toxicity. Very little is known about the effect of biotic and abiotic factors on the proliferation and the distribution of medusan nematocysts. In this study, we compared three types of nematocysts (euryteles and A- and O-isorhizas) and venoms of Cyanea capillata medusae (Scyphozoa) obtained from the North Sea and the Baltic Sea, which have different salinity and temperature ranges. Different types of nematocysts were separated by laser microdissection and pressure catapulting (LMPC), and the proteinaceous contents of the nematocysts were analyzed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Medusae from the brackish Baltic Sea possessed more euryteles than those from the North Sea. The O-isorhizas and A-isorhizas were smaller in the Baltic Sea sample compared to the North Sea samples and the length-to-width ratios were larger in the Baltic Sea sample. Moreover, the pattern of proteins (potential toxins) obtained from the separated nematocysts showed differences among samples and nematocyst types, but no clear pattern was observable. This study displays the novel LMPC/MALDI-TOF MS approach as a useful tool to investigate the function and venom of cnidarian nematocysts types.  相似文献   

13.
Reduction of protein levels in manufactured natural rubber latex products is important for preventing sensitization and adverse allergic reactions to latex. Because of the complex nature of latex extracts, accurate protein measurement is a challenge. Standard total protein assays were effective in reducing protein levels from what were once extremely high levels, but these assays are plagued with false-positive reactions and limited sensitivity. An ELISA for antigenic protein has been standardized and promises to provide more consistent measurement of the proteins with potential to cause adverse reactions. Antigenic proteins represent the total protein fraction with potential to be allergenic. Measuring antigenic protein in a consistent manner should help to further reduce the level of sensitizing protein and further reduce allergic reactions to latex-medical products.  相似文献   

14.

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   

15.
报道了中红侧沟茧蜂寄生粘虫时的某些生物学特性。雌蜂的每次产卵动作约有3.1%的比率产出两粒卵,4.6%的比率没有卵产出。寄主龄期与寄生率呈负相关关系,雌蜂在寄主体内产两粒卵能提高寄生率。寄主龄期同后代寄生蜂的性比没有相关性,不是影响性比的主要因素。文中讨论了影响中红侧沟茧蜂性比的可能因素,并认为二龄粘虫是大规模繁殖该寄生蜂的最好寄主。  相似文献   

16.

Background

Skin testing can expose allergic subjects to potential systemic reactions, sensitization against unrelated proteins, and increased risk of future sting reactions. Therefore the continuous improvement of in vitro diagnostic methods is desirable. Recombinant allergens have been shown to improve the sensitivity of specific IgE (sIgE) detection in vitro whilst no data is available regarding their application and reliability in basophil activation test (BAT). Here we aimed to compare the specificity and sensitivity of recombinant allergens Ves v 1, Ves v 2, Ves v 3 and Ves v 5 in both specific IgE (sIgE) detection in vitro and basophil activation test.

Methods

sIgE detection by ELISA or ImmunoCAP and BAT towards the panel of recombinant allergens Ves v 1, Ves v 2, Ves v 3 and Ves v 5 were performed in 43 wasp venom allergic patients with a history of anaphylactic reaction and sIgE seropositivity, as well as 17 controls defined as subjects with a history of repetitive wasp stings but absence of any allergic symptom.

Results

The BAT performed with the recombinant allergens Ves v 1, Ves v 2, Ves v 3 and Ves v 5 markedly improved the specificity of diagnosis in wasp venom allergic subjects when compared to the respective sIgE detection in serum.

Conclusions

BAT performed with the recombinant allergens Ves v 5, Ves v 3 and Ves v 1 provides an emerging highly specific in vitro method for the detection of wasp venom allergy, compared to the sIgE detection. Recombinant allergens applied to BAT represent a step forward in developing reliable in vitro tests for specific diagnosis of allergy.  相似文献   

17.
18.
19.
A working party of the British Society for Allergy and Clinical Immunology has reviewed the role of specific allergen immunotherapy in the treatment of allergic disease and produced a position statement summarising the available evidence for efficacy and safety. The working party recommends specific allergen immunotherapy for treating summer hay fever uncontrolled by conventional medication and for wasp and bee venom hypersensitivity. It is not recommended for asthma or for allergic rhinitis due to other allergens. For the recommended indications the risk:benefit ratio is acceptable provided patients are carefully selected; in particular, patients with asthma should be excluded as they are especially vulnerable to adverse reactions. Injections should be given only by doctors experiences in this form of treatment in a clinic where full resuscitative facilities are immediately available. Provided patients remain symptom free a 60 minute observation period after injection is sufficient to detect all serious adverse reactions.  相似文献   

20.
Abstract This paper deals with the bionomics of Microplitis mediator parasitizing Pseudaletia separata. There were some stings (ca. 3. 1%) in which female wasps oviposited more than one eggs and about 4. 6% stings that there was no egg laid into a host. A negative correlation existed between the host age and percentage of parasitization. When the host suffered more stings by the parasitoid wasps, the percentage of parasitization was higher. But there was no correlation between the parasitoid sex ratio and the host age or the frequency of stings by the parasitoids. The host age is not the major factor affecting the offspring sex ratio of the parasitoid. Some putative sex determinant factors in the parasitoid are discussed and the 2nd instar of the host is recommended as a suitable host age in which parasitization could be performed for the purpose of the parasitoid mass culture.  相似文献   

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