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Allergy to insects in Japan. III. High frequency of IgE antibody responses to insects (moth, butterfly, caddis fly, and chironomid) in patients with bronchial asthma and immunochemical quantitation of the insect-related airborne particles smaller than 10 microns in diameter.

After recognizing that moth, butterfly, caddis fly, and chironomid were the insects predominantly found in our environment, reaginic sensitivities to these insects in patients with asthma were investigated with extracts of silkworm wing for the detection of moth and/or butterfly allergy, caddis fly wing for caddis fly allergy, and chironomid whole body for chironomid allergy. At least 50% of 56 randomly selected patients with asthma had positive intracutaneous reactions to these insect extracts, and at least 80% of the skin reaction positive patients had specific IgE antibodies. An immunochemical assay of these insect-related aeroallergens in the dust collected 18.6 m above ground revealed the presence in the air of insect-related particles less than 10 microns in diameter with two peaks a year, one in the spring (silkworm wing, 3.18 ng protein equivalent to that of the crude extract per cubic meter of air; caddis fly wing, 3.08 ng/m3; and chironomid whole body, 5.21 ng/m3) and one in the autumn (silkworm wing, 8.24 ng/m3; caddis fly wing, 4.74 ng/m3; and chironomid whole body, 18.19 ng/m3). Although we have no idea whether or not such peak values are enough to cause asthmatic symptoms, seasonal fluctuations of specific IgE antibodies to these insects appeared to be similar to those of atmospheric insect allergens measured by this method. These findings suggest that insects are widespread and common inhalant allergens.

Adolescent

Insect immunity. Isolation from a coleopteran insect of a novel inducible antibacterial peptide and of new members of the insect defensin family.

Injection of heat-killed bacteria into larvae of the large tenebrionid beetle Zophobas atratus (Insecta, Endopterygota, Coleoptera) results in the appearance in the hemolymph of a potent antibacterial activity as evidenced by a plate growth inhibition assay. We have isolated three peptides (A-C) from this immune hemolymph which probably account for most of this activity. Their primary structures were established by a combination of peptide sequencing and molecular mass determination by mass spectrometry. Peptide A, which is bactericidal against Gram-negative cells, is a 74-residue glycine-rich molecule with no sequence homology to known peptides. We propose the name coleoptericin for this novel inducible antibacterial peptide. Peptides B and C are isoforms of a 43-residue peptide which contains 6 cysteines and shows significant sequence homology to insect defensins, initially reported from dipteran insects. This peptide is active against Gram-positive bacteria. The results are discussed in connection with recent studies on inducible antibacterial peptides present in the three other major orders of the endopterygote clade of insects: the Lepidoptera, Diptera, and Hymenoptera.

Amino Acid Sequence

Naturally occurring insect growth regulators. II. Screening of insect and plant extracts as insect juvenile hormone mimics.

Ethereal extracts prepared from the larvae, pupae, or eggs of 10 species of insects and from various parts of 343 species of higher plants were screened for juvenilizing effects against Tenebrio molitor and Oncopeltus fasciatus. Activity in both species was shown by an extract of the larvae of the stable fly, Stomoxys calcitrans, whereas an extract of the pupae was active in O. fasiatus only. Extracts of two plant species (Echinacea angustifolia roots and Chamaecyparis lawsoniana seeds) showed high juvenilizing activity in T. MOLITOR, AND EXtracts of five plant species (Clethra alnifolia stems, leaves, and fruits, Sassafras albidum roots and root bark, Eucalyptus camaldulensis stems and bark, Pinus rigida twigs and leaves, and Iris douglasiana roots, stems, and fruits) were highly active in O. fasciatus an extract of Tsuga canadensis leaves showed lower activity in this insect. Extracts of 16 species of plants showed high insecticidal activity (mortality) in O. fasciatus but lacked juvenilizing properties in both species of test insects.

Animals

Venom skin tests in insect-allergic and insect-nonallergic populations.

Intradermal skin tests with varying concentrations of honeybee, yellow jacket, white-faced hornet, yellow hornet, and Polistes venoms were done on 85 patients with histories of insect-sting anaphylaxis and on 56 insect-nonallergic subjects. Positive skin tests (wheal greater than or equal to 5 to 10 mm and flare greater than or equal to 11 to 20 mm) were present in 67 insect-allergic patients at venom concentrations ranging from 0.001 microgram/ml to 0.1 microgram/ml. Seven additional allergic patients had positive skin tests with the 1.0 microgram/ml venom concentration. Twenty-six nonallergic subjects had positive skin tests at the venom concentration of 1.0 microgram/ml, and two patients had positive skin tests at the lower venom concentrations (0.001 to 0.1 microgram/ml). These results confirm venom skin tests as a highly sensitive method of detecting venom-specific IgE in the evaluation of patients with stinging-insect hypersensitivity. Since a large percentage of insect-nonallergic subjects reacted to the 1.0 microgram/ml concentration, clinical judgment and further in vitro testing should be considered in the evaluation of patients who react only at this venom concentration.

Antibodies, Anti-Idiotypic

Detection of IgE antibodies to a wide range of insect species in subjects with suspected inhalant allergies to insects.

Sera obtained from subjects diagnosed on the basis of case history and skin tests as having inhalant allergies to insects, were tested for the presence of IgE antibodies to antigens from the house fly Musca domestica, a blowfly Calliphora stygia, the common clothes moth Tineola bisselliella, warehouse moth Ephestia cautella, cockroach Blattella germanica, carpet beetle Anthrenus verbasci and silverfish Ctenolepisma longicaudata. Approximately one-third of the sera reacted with extracts from all seven species, over half the sera reacted with four of the extracts and only 3 sera proved negative to all of the extracts. Twenty-six of the sera also contained IgE antibodies that reacted with the house dust mite Dermatophagoides farinae. Tests with a further eleven species of flies from the order Diptera and with extracts of the grain borer Rhyzopertha dominica, locust Chortoicetes terminifera and Bogong moth Agrotis infusa revealed strong IgE antibody responses to all of the species. Electroblotting studies revealed up to 15 IgE-binding components in extracts from 11 different insect species including 6 species of flies. Some IgE-binding insect components with similar electrophoretic mobilities indicated the possible presence of common allergens in extracts from different species. In particular, blots of each of the fly extracts showed a dense IgE-binding component of MW approximately 37,000 daltons. 'Pan allergy' to insects may occur in subjects who have been sensitized to one or a few insects and allergenic similarities may extend to at least some other noninsect members of the phylum Arthropoda.

Adolescent

[Infection of insect cell lines by the HIV virus, an agent of AIDS, and a demonstration of insects of African origin infected by this virus].

The etiological agent of AIDS known as HIV has been shown to bind on different insect cell lines including Drosophila, Mosquito, Ceratitis; and his DNA to be integrated in the cellular genome, but no expression of the viral genome was detected in those cells. None of the human lymphocytes markers is expressed at the surface of the insect cells. HIV proviral DNA has been also found in various insects from Central Africa (Zaïre and Central Africa Republic) but not similar insects from the Paris area. These data suggest that insects could be a reservoir or a vector for the AIDS virus.

Acquired Immunodeficiency Syndrome

Insect immunity: isolation from immune blood of the dipteran Phormia terranovae of two insect antibacterial peptides with sequence homology to rabbit lung macrophage bactericidal peptides.

We have isolated from the hemolymph of immunized larvae of the dipteran insect Phormia terranovae two peptides that are selectively active against Gram-positive bacteria. They are positively charged peptides of 40 residues containing three intramolecular disulfide bridges and differ from one another by only a single amino acid. These peptides are neither functionally nor structurally related to any known insect immune response peptides but show significant homology to microbicidal cationic peptides from mammalian granulocytes (defensins). We propose the name "insect defensins" for these insect antibiotic peptides.

Amino Acid Sequence

Insect growth regulators and insect control: a critical appraisal.

Insect growth regulators (IGRs) of the juvenile hormone type alter physiological processes essential to insect development and appear to act specifically on insects. Three natural juvenile hormones have been found in insects but not in other organisms. Future use of antagonists or inhibitors of hormone synthesis may be technically possible as an advantageous extension of pest control by IGRs. A documented survey of the properties, metabolism, toxicology, and uses of the most commercially advanced chemical, methoprene, shows it to be environmentally acceptable and toxicologically innocuous. Derivation of its current use patterns is discussed and limitations on these are noted. Residue levels and their measurement in the ppb region have allowed exemption from the requirement of tolerances in the EPA registered use of methoprene for mosquito control. Tolerances for foods accompany its fully approved use for control of manure breeding flies through a cattle feed supplement. The human health effects of using this chemical appear to be purely beneficial, but further advances through new IGR chemicals appear unlikely without major changes in regulatory and legislative policy.

Animals

Pharmacology of putative glutamate receptors from insect skeletal muscles, insect central nervous system and rat brain.

Binding of [3H]glutamate to housefly brain and honeybee brain and thoracic muscle membranes as well as to the American cockroach nerve cord was measured in Na+-free Tris-citrate buffer, 2.5 mM CaCl2, pH 7.4. The dissociation constants (KDS) ranged from 0.16 to 1.36 microM, and thoracic muscles had 2-4-fold higher density of receptors than brain tissue. The potent inhibitors of housefly brain binding were in decreasing order of effectiveness: L-glutamate greater than L-aspartate = L-cysteate = ibotenate greater than quisqualate greater than L-homocysteate greater than L-APB greater than L-APV greater than NMDA greater than D-APB greater than D-glutamate, with no inhibition by 100 microM of GDEE, dihydrokainate, D-APV, D-homocysteate or D-aspartate. The drug specificity of [3H]glutamate binding sites in housefly brain was generally similar to that of binding sites in housefly muscle, except that the former had a slightly higher affinity for L-APB, L-homocysteate and NMDA. [3H]Glutamate binding to insect tissues differed in its drug sensitivity from binding to rat brain. Binding to insect membranes was much less sensitive to L-APB, D-APB, APV, homocysteate, L-cysteate, quisqualate and ibotenate. However, the insect binding site was much more stereoselective for the L than D isomers of glutamate and aspartate, while the rat brain site was more stereoselective for APB. It is suggested that the observed [3H]glutamate binding to insect tissue is not to NMDA or kainate receptors.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals

Methods for dissecting dry insects and insects preserved in fixative solutions or by refrigeration.

The methods described in this paper for the dissection of dry and preserved insects have been used for several years on various species, mainly mosquitos. In the past, dry or partially dry mosquitos found in traps or in the laboratory had to be discarded. By softening these insects in a detergent solution, however, it is possible to make most observations in the same way as on fresh material. The preservation of insects in the dry state, in a fixative, or in the refrigerator after collection enables much larger samples to be studied; the whole of the material can be examined and the work can be done when time permits. In addition, material can be sent to central laboratories far from the place of collection, and infected insects can be kept in stock for teaching purposes.

Animals

An insect retina without microvilli in the male scale insect, Eriococcus sp. (eriococcidae, homoptera).

Male scale insects of an undescribed Australian species of Eriococcus have no compound eyes but show an extraordinary arrangement of three pairs of ocelli: One pair is positioned dorsolaterally where most insects have their compound eyes. Another pair looks ventrally and is placed where insects usually have their mouthparts, and there are two small lateral ocelli. Corneal nipples and a spherical lens with an estimated F-number only 0.55 are structural adaptations considered to increase the overall light sensitivity in order to compensate for the poor quantum capture of the shallow retina whose rhabdomes are only 3 micrometer long. The outer segment of each receptor cell consists of a central core of cytoplasm containing mitochondria and a peripheral cylinder of about 16 "rhabdomeres". There is no optical separation between neighbouring outer segments. Uniquely in arthropod eyes, the light sensitive structures are not composed of cylindrical microvilli, but consist of membrane stacks whose configuration is analogous to the stacked plates of vertebrate cones. At present no conclusive answer can be given as to why the photoreceptors have plates instead of microvilli. Comparative calculations show that they do not contain more photosensitive membrane per unit volume than rhabdomeres of fly ocelli.

Animals

Insect antibacterial proteins: not just for insects and against bacteria.

In response to a bacterial infection, insects launch an array of countermeasures. Among these are the antibacterial proteins, which effectively lyse bacteria or are bacteriostatic. These proteins were generally assumed to be restricted to insects, yet recent information has shown some homologous counterparts in vertebrates, including humans. Recent data have revealed that at least some of these proteins can also act against eukaryotic cells, including human infectious parasites. The latter activities have opened up new possibilities for disease control.

Animals

Immunological studies of the effect of whole body insect extracts in the treatment of stinging insect allergy.

Specific IgE antibodies and total antibodies reacting with bee venom and yellow jacket venom were measured in sequential serum samples of insect-sensitive individuals. Venom-specific IgE decreased as a function of time and was not significantly affected by treatment with whole body extracts. There was no stimulation of total antibodies reacting with bee venom phospholipase A2 (PLA) following treatment with whole bee body extracts. These studies suggest that as measured by these parameters, whole body insect extracts used in the usual recommended doses are immunologically ineffective antigens.

Antibody Specificity

[Insect bite allergy. Acute therapy and hyposensitization by means of insect venom].

Systemic reactions after an insect bite necessitate an allergologic investigation. In addition to taking the patient's history a skin test and an estimation of allergenspecific IgE should be performed. If insect bite allergy is confirmed immediate pharmacological treatment is necessary and hyposensitization therapy is recommended. Purified venom extracts are available.

Adrenal Cortex Hormones

Actions of potent cholinergic anthelmintics (morantel, pyrantel and levamisole) on an identified insect neurone reveal pharmacological differences between nematode and insect acetylcholine receptors.

Intracellular recording and current-clamp techniques were used to investigate the cholinergic activity of the anthelmintics, morantel, pyrantel and levamisole, applied to the fast coxal depressor motorneurone (Df) of the cockroach Periplaneta americana. Application of these agents and acetylcholine to the bath resulted in dose-dependent changes in conductance and corresponding depolarization of the neuronal membrane. Relative potencies of the drugs were determined from dose-response relationships and the rank order of effectiveness was as follows: carbachol much greater than levamisole greater than pyrantel greater than morantel. Evidence that these drugs were acting at the same site of action was obtained with the antagonist, mecamylamine, which abolished the responses to all these agents. It is concluded that the weak insecticidal action of these potent anthelmintics may result in part from their weak cholinergic agonist action on insect neurones, which contrasts with their potent agonist actions on acetylcholine receptors of helminth nerve and muscle tissues. The striking differences in potency on different invertebrate tissues appears to reflect differences in the properties of acetylcholine receptors between insects and nematodes. Further characterization of neurotransmitter receptors in invertebrates is needed in order to facilitate the rational design of broad-spectrum antiparasitic agents with low toxicity in mammals.

Animals

Adaptation of an insect cell line (Grace's Antheraea cells) to medium free of insect hemolymph.

Cultures of the insect cell line derived by Grace from Antheraea eucalypti Scott [Austrocaligula eucalypti (Scott)] were successfully adapted to medium supplemented with fetal bovine serum, whole-egg ultrafiltrate, and bovine plasma albumin instead of insect hemolymph. Cells, now in their 37th passage, have a population doubling time of 2.5 days; those of unadapted cultures, 4.2 days.

Animals

Horse-baited insect trap and mobile insect sorting table used in a disease vector identification study.

A horse-baited trap and a mobile insect sorting table were used to conduct an arthropod survey for potential vectors of Potomac Horse Fever in southern Maryland and northern Virginia. The trap and table worked effectively for the live collection and sorting of haemophagous Diptera such as: Simulium spp., Stomoxys calcitrans, Musca autumnalis, Tabanus spp. and Chrysops spp. during the diurnal collections periods, and Culicoides spp. during the crepuscular periods. The trap was not as convenient for live collection of mosquito species during the nocturnal period. Modifications to the trap design was suggested for mosquito live trapping.

Animals