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PubMedDate not supplied

[A modified ultra-rush-protocol of allergen immunotherapy in children and adolescents with insect venom allergy].

BACKGROUND: In Germany the prevalence of insect venom allergy in the population is about 5 %, 10-40 deaths are reported every year. With a success rate of 95 % venom immunotherapy (SIT) has a convincing protective effect. The purpose of this study was to investigate the safety of the original ultra-rush-protocol in children and reduce from 9 to 8 doses by avoiding a second application of 100 micro g insect venom. METHODS: Nineteen children and adolescents with insect venom allergy were treated according to the modified ultra-rush-protocol. The first 5 children were hyposensitized according to the original protocol suggested by Brehler et al., the remaining 14 children (age 6-18 years) received only 8 injections (0.01/0.1/1/10/20/40/80/100 micro g). 5 patients were discharged on the second day four hours after the final application of 100 micro g insect venom. RESULTS: Extensive reddening due to inflammation was found in injection spot in 5 patients. Four patients had an amplified wheal formation. No systemic reactions were observed. The maintenance therapy was well tolerated. CONCLUSION: The modified ultra-rush-protocol increases compliance by short inpatient stay. In addition the modified hyposensitization was sure and well tolerated.

Adolescent↗
PubMed2004

Outcomes of allergy to insect stings in children, with and without venom immunotherapy.

BACKGROUND: Children are thought to "outgrow" the allergy to insect stings, but there are no reports documenting the natural history of this reaction. We studied the outcome of allergic reactions to insect stings in childhood 10 to 20 years afterward in patients who had not received venom immunotherapy and in those who had been treated. METHODS: Between 1978 and 1985, we diagnosed allergic reaction to insect stings in 1033 children, of whom 356 received venom immunotherapy. We conducted a survey of these patients by telephone and mail between January 1997 and January 2000, to determine the outcome of stings that occurred in the period from 1987 through 1999. RESULTS: Of the 1033 patients, 512 patients (50 percent) responded, with a mean follow-up period of 18 years, a mean duration of venom immunotherapy of 3.5 years in treated patients, and an incidence of stings of 43 percent. Systemic reactions occurred less frequently in patients who had received venom immunotherapy (2 of 64 patients, or 3 percent) than in untreated patients (19 of 111 patients, or 17 percent; P=0.007). Patients with a history of moderate-to-severe reactions had a higher rate of reaction if they had not been treated (7 of 22 patients, or 32 percent) than if they had received venom immunotherapy (2 of 43 patients, or 5 percent; P=0.007). In patients who had been treated and who had a history of mild (cutaneous) systemic reaction (i.e., one with only cutaneous manifestations), none of the 21 subjects who received stings had a systemic reaction. CONCLUSIONS: A clinically important number of children do not outgrow allergic reactions to insect stings. Venom immunotherapy in children leads to a significantly lower risk of systemic reaction to stings even 10 to 20 years after treatment is stopped, and this prolonged benefit is greater than the benefit seen in adults.

Animals↗
PubMed2001

Insect sting allergy with negative venom skin test responses.

BACKGROUND: In our 1976 controlled venom immuno rapy trial, 33% of 182 patients with a history of systemic reactions to insect stings were excluded because of negative venom skin test responses. There have been reports of patients with negative skin test responses who have had severe reactions to subsequent stings. OBJECTIVE: Our aim is to increase awareness about the patient with a negative skin test response and insect sting allergy and to determine the frequency and significance of negative skin test responses in patients with a history of systemic reactions to insect stings. METHODS: We prospectively examined the prevalence of negative venom skin test responses in patients with a history of systemic reactions to stings. In patients who gave informed consent, we analyzed the outcome of retesting and sting challenge. RESULTS: Of 307 patients with positive histories screened for our sting challenge study, 208 (68%) had positive venom skin test responses (up to 1 microg/mL concentration), and 99 (32%) had negative venom skin test responses. In 36 (36%) of the 99 patients with negative skin test responses, the venom RAST result was a low positive (1-3 ng/mL), or repeat venom skin test responses were positive; another 7 (7%) patients had high venom-specific IgE antibody levels (4-243 ng/mL). Notably, 56 (57%) of 99 patients with positive histories and negative skin test responses had negative RAST results. In patients with positive skin test responses, sting challenges were performed in 141 of 196 patients, with 30 systemic reactions. Sting challenges were performed on 37 of 43 patients with negative skin test responses and positive venom-specific IgE and in 14 of 56 patients with negative skin test responses and negative RAST results. There were 11 patients with negative skin test responses who had systemic reactions to the challenge sting: 2 had negative RAST results, and 9 had positive RAST results at 1 ng/mL. The frequency of systemic reaction was 21% in patients with positive skin test responses and 22% in patients with negative skin test responses (24% in those with positive RAST results and 14% in those with negative RAST results). CONCLUSIONS: Venom skin test responses can be negative in patients who will subsequently experience another systemic sting reaction. Venom skin test responses are negative in many patients with a history of systemic allergic reactions to insect stings and may be associated with positive serologic test responses for venom-specific IgE antibodies (sometimes strongly positive results). Venom skin test responses should be repeated when negative, along with a serologic IgE antivenom test. Better diagnostic skin test reagents are urgently needed.

Academic Medical Centers↗
PubMed1998

Insect juvenile hormone resistance gene homology with the bHLH-PAS family of transcriptional regulators.

Juvenile hormone analog (JHA) insecticides are relatively nontoxic to vertebrates and offer effective control of certain insect pests. Recent reports of resistance in whiteflies and mosquitoes demonstrate the need to identify and understand genes for resistance to this class of insect growth regulators. Mutants of the Methoprene-tolerant (Met) gene in Drosophila melanogaster show resistance to both JHAs and JH, and previous biochemical studies have demonstrated a mechanism of resistance involving an intracellular JH binding-protein that has reduced ligand affinity in Met flies. We cloned the Met+ gene by transposable P-element tagging and found reduced transcript level in several mutant alleles, showing that underproduction of the normal gene product can lead to insecticide resistance. Transformation of Met flies with a Met+ cDNA resulted in susceptibility to methoprene, indicating that the cDNA encodes a functional Met+ protein. MET shows homology to the basic helix-loop-helix (bHLH)-PAS family of transcriptional regulators, implicating MET in the action of JH at the gene level in insects. This family also includes the vertebrate dioxin receptor, a transcriptional regulator known to bind a variety of environmental toxicants. Because JHAs include a diverse array of chemicals with JH activity, a mechanism whereby they can exert effects in insects through a common pathway is suggested.

Amino Acid Sequence↗
PubMed1994

DNA-based methods for the identification of insect vectors.

Many insect vectors are members of complexes composed of morphologically identical sibling species. The identification of individual species, a requirement of epidemiological studies and control programmes, has traditionally relied upon techniques such as chromosomal analysis or isoenzyme typing. Owing to the limitations of these techniques, the last few years have seen many developments in DNA-based technologies for identification. DNA-based protocols have advantages over the other techniques utilized, in that they may identify all insect stages of both sexes using alcohol-preserved, dried, fresh or frozen specimens. The methods ultimately rely upon either DNA probe hybridization or the polymerase chain reaction (PCR). This review describes a number of approaches taken towards the development of these techniques. The aim of these approaches, whether directed or random, is to produce a methodology that is cheap, accurate and easy to use. In this review, the DNA-based techniques developed for the identification of Anopheles gambiae complex mosquitoes are used to illustrate the power of these methods, although, as the review demonstrates, the technology is directly applicable to many other mosquito or insect vectors. In addition, the methods discussed may be utilized for generating additional epidemiological data, such as identification of parasites within the vector or origin of the bloodmeal. A comprehensive survey of the probe systems available for the identification of insect vectors and the disease-causing organisms they transmit to the human population is therefore included. Given further advances in this technology, it may be anticipated that DNA-based approaches to identification may eventually supersede more traditional methodologies in the fields of tropical medicine and parasitology.

Animals↗
PubMed1975

Manipulating sex pheromones for insect suppression.

A review is given of different methods of using sex pheromones in pest control programs. Survey and monitoring traps have been used extensively for determining the presence and abundance of pest populations are commercially available. Pheromone trapping studies for insect suppression have shown success with some species and could be a useful tool in some situations. The technique of attracting insects to the host for insect removal or exposure to insecticide has also proved to be useful in some programs. Mating disruption studies using widely-separated pheromone evaporators or encapsulated pheromone distributed throughout an area have indicated a great potential for this technique in insect suppression programs.

Agriculture↗
PubMed2003

Impact of a nucleopolyhedrovirus bioinsecticide and selected synthetic insecticides on the abundance of insect natural enemies on maize in southern Mexico.

The impact of commonly used organophosphate (chlorpyrifos, methamidophos), carbamate (carbaryl), and pyrethroid (cypermethrin) insecticides on insect natural enemies was compared with that of a nucleopolyhedrovirus (Baculoviridae) of Spodoptera frugiperda (J. E. Smith) (Lepidoptera Noctuidae) in maize grown in southern Mexico. Analyses of the SELECTV and Koppert Side Effects (IOBC) databases on the impact of synthetic insecticides on arthropod natural enemies were used to predict approximately 75-90% natural enemy mortality after application, whereas the bioinsecticide was predicted to have no effect. Three field trails were performed in mid- and late-whorl stage maize planted during the growing season in Chiapas State, Mexico. Synthetic insecticides were applied at product label recommended rates using a manual knapsack sprayer fitted with a cone nozzle. The biological pesticide was applied at a rate of 3 x 10(12) occlusion bodies (OBs)/ha using identical equipment. Pesticide impacts on arthropods on maize plants were quantified at intervals between 1 and 22 d postapplication. The biological insecticide based on S. frugiperda nucleopolyhedrovirus had no adverse effect on insect natural enemies or other nontarget insect populations. Applications of the carbamate, pyrethroid, and organophosphate insecticides all resulted in reduced abundance of insect natural enemies, but for a relatively short period (8-15 d). Pesticide applications made to late-whorl stage maize resulted in lesser reductions in natural enemy populations than applications made at the mid-whorl stage, probably because of a greater abundance of physical refuges and reduced spray penetration of late-whorl maize.

Animals↗
PubMed2004

Efficacy of Piper (Piperaceae) extracts for control of common home and garden insect pests.

Extracts from three species of the plant family Piperaceae, Piper nigrum [L.], Piper guineense [Schum & Thonn, and Piper tuberculatum [Jacq.], were tested for efficacy against insects from five orders. All three species contain isobutyl amides, plant secondary compounds that act as neurotoxins in insects. These materials are considered safe to mammals because Piper spp. were used for centuries for spice and medicinal purposes. When 24-h P. nigrum LC50 values were compared between common insect pests from eastern Canada and the northeastern United States, the most sensitive species in order of increasing lethal concentration were eastern tent caterpillar, Malacosoma americanum (F.) < European pine sawfly larvae, Neodiprion sertifer (Geoffroy) < spindle ermine moth larvae, Yponomeuta cagnagella [Hübner] < viburnum leaf beetle larvae, Pyrrhalta viburni [Paykull] < stripped cucumber beetle adults, Acalymma vittatum (F.) < Colorado potato beetle adults, Leptinotarsa decemlineata (Say) < Japanese beetle adults, Popillia japonica [Newman] < hairy chinch bug, Blissus leucopterus hirtis [Montandon]. The life stage tested was the point at which each species causes the greatest amount of damage to the host plant and the point at which most gardeners would likely choose to treat with a conventional synthetic insecticide. Greenhouse trials revealed that the pepper formulations also had a repellent activity, thus protecting plant leaves from 1) herbivory (lily leaf beetle, Lilioceris lilii [Scopoli], adults and larvae and stripped cucumber beetle adults) and 2) oviposition [European corn borer, Ostrinia nubilalis (Hübner)]. Combinations with other botanical extracts were additive at best in toxicity and repellent trials. Nontarget toxicity to beneficial invertebrates is a possibility because the P. nigrum LC50 for beneficial ladybird beetles was 0.2%. P. nigrum extracts can provide a reasonable level of control against lepidopteran and European pine sawfly larvae and also will work as a short-term repellent and feeding deterrent. It is recommended that the use of Piper extracts be restricted to small-scale spot treatments in residential areas where insect pest outbreaks have occurred.

Animals↗
PubMed2005

Insect contribution to horizontal transmission of Reticuloendotheliosis virus.

The involvement of insects in Reticuloendotheliosis virus (REV) transmission was examined by testing insects trapped at commercial farms and by controlled feeding experiments using mosquitoes, Culex pipiens L. and house flies, Musca domestica L. We established sensitive methods of REV detection, including reverse transcription-polymerase chain reaction (PCR) for REV-LTR and REV-gag genes, REV antigenemia measurements by enzyme-linked immunosorbent assay, and virus isolation in tissue cultures. A variety of blood-sucking species of insects were trapped at farms with infected poultry and tested, but none were positive. To rule out the possibility of PCR inhibition by insect RNA, spiking experiments were conducted and no interference was observed. Because Cx. pipiens mosquitoes were trapped frequently at farms, we performed feeding experiments with mosquito females fed on a REV-containing tissue culture medium and chicken blood mixture. Virus was detected in the mosquitoes up to 5 h postfeeding, compared with 96 h in the feeding mixture, indicating that Cx. pipiens can only harbor REV for a short period. House flies were suspected to be involved in the virus transmission because they frequently were trapped on positive farms. In contrast to mosquitoes, REV was harbored within the house fly digestive tract for up to 72 h and could infect chickens, as demonstrated by seroconversion and by detection of viral gag-sequence in the cloaca. The current study is supportive for the role of house flies as a mechanical vector of REV among poultry.

Animals↗
PubMed2004

Early duplication and functional diversification of the opsin gene family in insects.

Recent analysis of the complete mosquito Anopheles gambiae genome has revealed a far higher number of opsin genes than for either the Drosophila melanogaster genome or any other known insect. In particular, the analysis revealed an extraordinary opsin gene content expansion, whereby half are long wavelength-sensitive (LW) opsin gene duplicates. We analyzed this genomic data in relationship to other known insect opsins to estimate the relative timing of the LW opsin gene duplications and to identify "missing" paralogs in extant species. The inferred branching patterns of the LW opsin gene family phylogeny indicate at least one early gene duplication within insects before the emergence of the orders Orthoptera, Mantodea, Hymenoptera, Lepidoptera, and Diptera. These data predict the existence of one more LW opsin gene than is currently known from most insects. We tested this prediction by using a degenerate PCR strategy to screen the hymenopteran genome for novel LW opsin genes. We isolated two LW opsin gene sequences from each of five bee species, Bombus impatiens, B. terrestris, Diadasia afflicta, D. rinconis, and Osmia rufa, including 1.1 to 1.2 kb from a known (LW Rh1) and 1 kb from a new opsin gene (LW Rh2). Phylogenetic analysis suggests that the novel hymenopteran gene is orthologous to A. gambiae GPRop7, a gene that is apparently missing from D. melanogaster. Relative rate tests show that LW Rh2 is evolving at a slower rate than LW Rh1 and, therefore, may be a useful marker for higher-level hymenopteran systematics. Site-specific rate tests indicate the presence of several amino acid sites between LW Rh1 and LW Rh2 that have undergone shifts in selective constraints after duplication. These sites and others are discussed in relationship to putative structural and functional differences between the two genes.

Amino Acid Sequence↗
PubMed2002

Ocular lesions arising after stings by hymenopteran insects.

PURPOSE: To describe the ocular lesions that occur after stings from hymenopteran insects. METHODS: We examined the ocular alterations in five patients who suffered ocular trauma from hymenopteran insect stings. RESULTS: In 4 cases where the insect was identified as a wasp, all the patients presented with persistent corneal decompensation and two presented with total cataract, requiring surgical treatment. In the case of trauma by a bee sting, the patient presented with corneal edema and an inflammatory reaction of the anterior chamber with total regression of these alterations after clinical treatment. CONCLUSION: Although a rare occurrence, ocular trauma caused by hymenopteran insects can result in severe ocular alterations in humans.

Adult↗
PubMed1986

Insect bites and stings: managing allergic reactions.

This article concerns itself with three common reactions (local, toxic and anaphylactic) resulting from insect or arthropod bites and stings. A local reaction consists of sharp, localized pain followed by a reddening at the site, which usually resolves itself in 24 hours. A toxic reaction may include gastrointestinal symptoms, fever, headache, dizziness or convulsions, often following an episode of multiple stings. An anaphylactic reaction may be mild (hives, itching) or severe (systemic reactions including airway and cardiovascular symptoms). Even though most bites and stings are not serious, nurse practitioners should be aware of potential death resulting from insect sting allergy. They should teach hypersensitive patients, or patients with a history of a systemic reaction to any agent, about prophylactic measures. Tables showing the characteristics of insects that cause cutaneous lesions in humans, and measures necessary to decrease the risk of being stung, can be used as learning tools to prevent insect sting allergy. Because of the rapid onset of anaphylaxis, life-saving measures include awareness in persons who are hypersensitive, emergency preparedness and preventing bites and stings from occurring.

Aminophylline↗
PubMed2005

Unusual reactions to insect stings.

PURPOSE OF REVIEW: A variety of unusual or unexpected reactions have occurred in a temporal relationship to insect stings. This review will summarize these case history reports in recent years. As these reactions are very infrequent, the review will also include prior reported unusual reactions attributed to insect stings. RECENT FINDINGS: Acute encephalopathy occurred 8 days after yellow jacket stings, without any other obvious cause. There have been prior reports of other neurological reactions, myasthenia gravis, peripheral neuritis and Guillain-Barré syndrome related to insect stings. Acute renal failure with tubular necrosis has occurred following massive numbers of stings from Africanized honeybees. Nephrotic syndrome has been reported in the past following single stings. Silent myocardial infarction has occurred, probably related to acute anaphylactic symptoms immediately following a sting. There are recent reports of other pathology, diffuse alveolar hemorrhage and rhabdomyolysis and prior reports of thrombocytopenic purpura and vasculitis. As the result of ocular stings, local reactions have occurred with corneal pathology leading to cataracts. Other prior reported reactions to ocular stings include conjunctivitis, corneal infiltration, lens subluxation, and optic neuropathy. There is scarce information regarding the pathogenesis of the majority of the unusual reactions and the subsequent allergic status or risk for sting anaphylaxis of people who have had these unusual reactions. SUMMARY: This review includes a variety of reactions, particularly involving neurological, renal and cardiovascular symptoms, related to insect stings. It is important that clinicians be aware of this relationship when assessing people with these reactions and address future prophylaxis.

Acute Kidney Injury↗
PubMed2006

Insect allergy in children.

PURPOSE OF REVIEW: Some aspects of insect sting allergy are unique in children. This review will identify and update the published data that exist pertaining specifically to insect allergy in children. RECENT FINDINGS: Children have a different pattern of insect sting allergy than adults. Honeybee allergy is more common in children. Severe systemic reactions are less common than in adults but the risk of recurrence can persist for decades. Systemic reactions are limited to mild 'cutaneous' reactions in over 60% of children (but only 15% of adults). Children with mild systemic reactions rarely get worse. Children with moderate or severe systemic reactions still had a 30% chance of a similar reaction even 20 years later. The long-term immune tolerance induced by venom immunotherapy is greater in children than adults. Children who had received venom immunotherapy for 3-5 years were still immune 10-20 years later. SUMMARY: Children with insect sting allergy are tested and treated in much the same way as adults. Children with mild systemic reactions do not require testing or immunotherapy. Children with moderate to severe systemic reactions are at risk for decades and should receive venom immunotherapy, which gives very long-lasting protection.

Anaphylaxis↗
PubMed2006

Absence of plasmids encoding adhesion-related proteins in non-insect-transmissible strains of Spiroplasma citri.

In the plant-pathogenic mollicute Spiroplasma citri, spiralin is the major lipoprotein at the cell surface and is thought to be one of the components involved in the interactions of the spiroplasma with its insect vector. With the aim of identifying surface proteins other than spiralin, monoclonal antibodies (mAbs) were produced by immunization of mice with the spiralin-defective S. citri mutant GII3-9a2. mAb 10G3 was found to react with several polypeptides of 43-47 and 80-95 kDa, all of which were detected in the detergent phase after Triton X-114 partitioning of proteins. Mass spectrometry (MALDI-TOF) analyses of the two major polypeptides P47 and P80 of GII3-9a2, reacting with mAb 10G3, revealed that P47 was a processed product and represented the C-terminal moiety of P80. Search for sequence homologies revealed that P80 shared strong similarities with the S. citri adhesion-related protein P89 (Sarp1) of S. citri BR3, and is one (named Scarp4a) of the eight Scarps encoded by the S. citri GII-3 genome. The eight scarp genes are carried by plasmids pSci1-5. Western immunoblotting of proteins with mAb 10G3 revealed that, in contrast to the insect-transmissible S. citri strain GII-3, the non-insect-transmissible strains ASP-1, R8A2 and 44 did not express Scarps. Southern blot hybridization experiments indicated that these strains possessed no scarp genes, and did not carry plasmids pSci1-5. However, S. citri strain GII3-5, lacking pSci5, was still efficiently transmitted, showing that, in the genetic background of S. citri GII-3, the pSci5-encoded genes, and in particular scarp2b, 3b and 5a, are not essential for insect transmission. Whether plasmid-encoded genes are involved in transmission of S. citri by its leafhopper vector remains to be determined.

Amino Acid Sequence↗
PubMed2005

Studies on overwintering of bluetongue viruses in insects.

Bluetongue viruses (BTVs) are economically important arboviruses that affect sheep and cattle. The overwintering mechanism of BTVs in temperate climates has eluded researchers for many years. Many arboviruses overwinter in their invertebrate vectors. To test the hypothesis that BTVs overwinter in their vertically infected insect vectors, Culicoides sonorensis larvae were collected from long-term study sites in northern Colorado, USA, and assayed for the presence of BTV RNA by nested RT-PCR. Sequences from BTV RNA segment 7 were detected in 30 % (17/56) of pools composed of larvae and pupae collected in 1998 and in 10 % (31/319) of pools composed of adults reared from larvae collected in 1996. BTV was not isolated from the insects. Additionally, Culicoides cell-culture lines derived from material collected at one of the sites, or derived from insect samples collected during a BTV outbreak, contained BTV RNA segment 7. In contrast, segment 2 RNA was detected at half the rate of segment 7 RNA in the field-collected larvae and was only detected in the Culicoides cell lines with one of two primer sets. These data suggest that BTVs could overwinter in the insect vector and that there is reduced expression of the outer capsid genes during persistent infection.

Animals↗
PubMed2003

Structure of an insect delta-class glutathione S-transferase from a DDT-resistant strain of the malaria vector Anopheles gambiae.

Glutathione S-transferases (GSTs) are a major family of detoxification enzymes which possess a wide range of substrate specificities. Most organisms possess many GSTs belonging to multiple classes. Interest in GSTs in insects is focused on their role in insecticide resistance; many resistant insects have elevated levels of GST activity. In the malaria vector Anopheles gambiae, elevated GST levels are associated with resistance to the organochlorine insecticide DDT [1,1,1-trichloro-2,2-bis-(p-chlorophenyl)ethane]. This mosquito is the source of an insect GST, agGSTd1-6, which metabolizes DDT and is inhibited by a number of pyrethroid insecticides. The crystal structure of agGSTd1-6 in complex with its inhibitor S-hexyl glutathione has been determined and refined at 2.0 A resolution. The structure adopts a classical GST fold and is similar to those of other insect delta-class GSTs, implying a common conjugation mechanism. A structure-based model for the binding of DDT to agGSTd1-6 reveals two subpockets in the hydrophobic binding site (H-site), each accommodating one planar p-chlorophenyl ring.

Amino Acid Sequence↗
PubMed1996

The insect cytochrome oxidase I gene: evolutionary patterns and conserved primers for phylogenetic studies.

Insect mitochondrial cytochrome oxidase I (COI) genes are used as a model to examine the within-gene heterogeneity of evolutionary rate and its implications for evolutionary analyses. The complete sequence (1537 bp) of the meadow grasshopper (Chorthippus parallelus) COI gene has been determined, and compared with eight other insect COI genes at both the DNA and amino acid sequence levels. This reveals that different regions evolve at different rates, and the patterns of sequence variability seems associated with functional constraints on the protein. The COOH-terminal was found to be significantly more variable than internal loops (I), external loops (E), transmembrane helices (M) or the NH2 terminal. The central region of COI (M5-M8) has lower levels of sequence variability, which is related to several important functional domains in this region. Highly conserved primers which amplify regions of different variabilities have been designed to cover the entire insect COI gene. These primers have been shown to amplify COI in a wide range of species, representing all the major insect groups; some even in an arachnid. Implications of the observed evolutionary pattern for phylogenetic analysis are discussed, with particular regard to the choice of regions of suitable variability for specific phylogenetic projects.

Amino Acid Sequence↗