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At least 793 records · Page 44Linked to original sources
PubMed1987

Toxic and antifeeding actions of melittin in the corn earworm, Heliothis zea (Boddie): comparisons to bee venom and the insecticides chlorpyriphos and cyromazine.

The acute and sublethal effects of melittin were compared to whole bee venom, chlorpyriphos and cyromazine injected into the corn earworm, Heliothis zea (Boddie). Melittin had twice the toxicity of crude venom, but only 3% that of chlorpyriphos. Melittin significantly reduced growth rate, diet consumption and food utilization efficiencies of fourth instar larvae. Bee venom and insecticides reduced these parameters to a lesser extent.

Bee Venoms↗
PubMed1987

The purification of acid phosphatase from honey bee venom (Apis mellifica).

Acid phosphatase from bee venom was purified by a combination of saturated ammonium sulphate precipitation, gel filtration and ion exchange chromatography. The final product which is a glycoprotein contained less than 0.1% phospholipase A2 or hyaluronidase activity and existed in two molecular weight (96,000 and 45,000) forms. Acid phosphatase is a potent allergen, in bee venom allergic patients, which is capable of releasing histamine from sensitized human basophils and of inducing a wheal and flare reactions in sensitized human skin.

Acid Phosphatase↗
PubMed1992

Rhabdomyonecrosis experimentally induced in Wistar rats by Africanized bee venom.

Damage is reported to skeletal muscle experimentally induced in Wistar rats by Africanized bee venom (ABV). Rhabdomyonecrosis was demonstrated indirectly by increased serum levels of the enzymes aspartate-aminotransferase and total creatine kinase, and directly by necrosis and inflammation observed by standard light microscopy of skeletal muscle. To our knowledge, this is the first report of a systemic damaging effect of ABV on skeletal muscle of experimentally envenomated rats. These data appear to reproduce experimentally some of the findings reported in cases of human envenomation due to multiple Africanized bee stings.

Animals↗
PubMed1993

Toxic effects of human pancreatic and snake and bee venom phospholipases A2 on MCF-7 cells in culture.

The toxicity of phospholipase A2 (PLA2) has been suggested to be involved in the pathology of a number of severe diseases including septic shock and acute pancreatitis. However, testing the toxicity of these substances is difficult in vivo. In the present study we compared the toxicity of PLA2s from three snake venoms, bee venom and human pancreas on MCF-7 cells grown in culture. Tetrazolium microculture assays were developed to test the cytostatic and cytotoxic effects of PLA2 on MCF-7 cells. These tests are based on the ability of viable cells to reduce a tetrazolium-based compound MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] to a blue formazan product. Leakage of lactate dehydrogenase (LD) from the cells into the culture medium was also measured. There were marked differences in the toxicity of the PLA2s tested. Cobra (Naja mosambique mosambique) venom PLA2 was toxic to the cells at a concentration of 4.5 U/ml. Light microscopic changes were seen in the injured cells after 3 hr treatment. Sixty-seven per cent of cells were dead after 24 hr treatment. Treatment for 4 hr caused irreversible changes in the cells. Leakage of LD was noted from 4 hr onwards. Other snake (Crotalus adamanteus and Laticauda semifasciata) venom PLA2s, even after continuous exposure to 4.5 U/ml caused only slight decreases in values obtained in the MTT test. No morphologic changes suggesting a cytotoxic effect were seen. PLA2 from bee (Apis mellifera) venom had no toxic effect, either. Continuous exposure of cells to human pancreatic PLA2 caused a 15% decrease in the MTT-test.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1985

The evaluation of the common diagnostic methods of hypersensitivity for bee and yellow jacket venom by means of an in-hospital insect sting.

Between 1979 and 1983 230 patients visited our clinic in connection with allergic reactions after insect stings. One hundred six patients were subjected to a diagnostic provocation test with a live insect; 86 of these patients had a history of systemic reactions and a positive skin test and RAST with insect venom. Thirty-one of these patients, including one patient with a negative RAST and another with a negative skin test, demonstrated a generalized reaction and were subjected to immunotherapy with pure insect venom. Comparison of the diagnostic data from 31 patients with reactions with those of the 57 nonreacting patients from the 86 patients aforementioned reveals that at this time only a provocation test with a live insect can provide the evidence of an allergy to insect venom leading to such a severe generalized reaction that admission to probably lifelong immunotherapy is justified. The measurement of the venom-specific IgG, the ratio of IgG/IgE, and (for bee patients) the serum antibody titer against the bee venom components phospholipase A and hyaluronidase did not improve the diagnosis of a current hypersensitivity against insect venom.

Adolescent↗
PubMed1986

Lack of responsiveness of beekeeper mononuclear cells to in vitro stimulation with pure bee venom.

Lymphocyte proliferation activity after in vitro bee venom (BV) stimulation was examined in a group of patients allergic to bee stings and in a group of beekeepers. Although the allergic patients responded strongly to increasing doses of BV, the beekeepers demonstrated no proliferative activity and an inability to produce interleukin-2 after BV stimulation. Removal of adherent cells or various populations of suppressor cells, including T gamma cells and OKT8 positive cells, did not influence the cellular unresponsiveness of cells of beekeepers after BV stimulation. Furthermore, cells of beekeepers, when they were trypsinized or when they were preincubated for 72 hours, did not proliferate after BV challenge. It is concluded that the lack of proliferation of lymphocytes of beekeepers and the inability to produce interleukin-2 is not due to a suppressor mechanism or to the presence of anti-idiotype antibodies coating the surface of lymphocytes of beekeepers. The mechanism behind the failure of cells of beekeepers to proliferate remains unclear.

Adult↗
PubMed1994

Human monoclonal or polyclonal antibodies recognize predominantly discontinuous epitopes on bee venom phospholipase A2.

BACKGROUND: Two hybridomas, which secrete human monoclonal antibodies of IgG4 isotype specific for the main bee venom antigen/allergen phospholipase A2, were generated. The antigenic determinants recognized by these antibodies were mapped and compared with the binding sites of murine monoclonal and human polyclonal antibodies raised against the same antigen. METHODS: Two hybridomas were developed by fusing heteromyelomas to Epstein-Barr virus immortalized B cells obtained from beekeepers. The cloned hybridomas were stable and secreted up to 40 mg/L of antibody into the culture supernatant. Phospholipase A2 specificity of the human monoclonal antibodies was confirmed by binding and inhibition ELISA and by Western blot analysis. Epitope mapping on phospholipase A2 was done with the PEPSCAN method and ELISA techniques. RESULTS: The epitopes recognized by the human monoclonal antibodies were shown to be discontinuous and did not contain the sugar residue. Similar results were obtained with polyclonal antibodies of IgG4 isotype (from beekeepers) specific for phospholipase A2, which could also inhibit the binding of the human monoclonal antibodies to phospholipase A2. In contrast, antigen binding of the human monoclonal antibodies could not be inhibited by murine monoclonal antibodies against bee venom phospholipase A2. CONCLUSIONS: The data indicate that the human monoclonal antibodies obtained are representative of a part of the polyclonal immune response to phospholipase A2 from beekeepers and may allow a more precise analysis of the humoral immune response to phospholipase A2 that is associated with protection.

Animals↗
PubMed1983

Age and oxygen toxicity related fluorescence in the honey bee thorax.

The blue fluorescent material in thoraxes of honey bees of known adult age from eclosion to 28 days was measured. The amount was greater in older insects and exposure to ozone (ppm) augmented the rate of accumulation. The nearly constant daylight flying by the bees and the ozone effect suggest radical peroxidative origin of the fluorescence. The material was partially purified by chromatography. It is a relatively non-polar lipid.

Aging↗
PubMed1990

Hemolytic potency and phospholipase activity of some bee and wasp venoms.

1. The action of crude venoms of four aculeate species: Apis mellifera, Vespa crabro, Vespula germanica and Vespula vulgaris on human erythrocytes was investigated in order to determine the lytic and phospholipase activity of different aculeate venoms and their ability to induce red blood cell hemolysis. 2. Bee venom was the only extract to completely lyse red blood cells at the concentration of 2-3 micrograms/ml. 3. Phospholipase activity in all of the examined vespid venoms was similar and the highest value was recorded in V. germanica. 4. Vespid venoms exhibited phospholipase B activity, which is lacking in honeybee venom. 5. In all membrane phospholipids but lecithin, lysophospholipase activity of vespid venoms was 2-6 times lower than the relevant phospholipase activity. 6. The incubation of red blood cells with purified bee venom phospholipase A2 was not accompanied by lysis and, when supplemented with purified melittin, the increase of red blood cell lysis was approximately 30%.

Bee Venoms↗
PubMed2005

Peritrophic membrane protein in the larval stingless bee Melipona quadrifasciata anthidioides: immunolocalization of secretory sites.

The origin of the peritrophic membrane (PM) in bees is still a matter of debate. It is either of type I (synthesized by the entire midgut epithelium) or of type II (released from the anterior midgut end). The present study identified secretory sites of peritrophin-55 kDa, a PM protein in larvae of Melipona quadrifasciata anthidioides. Peritrophin-55 was isolated from PMs and was used for the production of a polyclonal antibody. Our study demonstrates the presence of peritrophin-55 in vesicles and on microvilli of digestive cells and in the PM. It suggests that the PM is of type-I, being specific for the larval phase of this stingless bee.

Animals↗
PubMedDate not supplied

Bee stings of children: when to perform endotracheal intubation?

Hymenoptera stings account for more deaths in United States that any other envenomation. Oropharyngeal stings, although rare, may produce life-threatening airway obstruction by way of localized swelling. We present 4 cases of bee stings in children that necessitated tracheal intubation and mechanical ventilation. Two children had breathing difficulties at admission; the other 2 presented with minimal symptoms but were preventively intubated and mechanically ventilated. Orofacial bee sting victims should be given parenteral treatment with epinephrine, steroids, antihistamines, and inhalational bronchodilators even when they initially present with minimal symptoms, with general anaphylaxis management in large envenomations, as well as immediate endotracheal intubation and mechanical ventilation for at least 24 hours in patients with signs of airway compromise.

Airway Obstruction↗
PubMed2004

[Honey bees massive poisoning in an infant].

The authors report the case of an infant who survived a massive poisoning of honey bees (>350 bees stings) in 2002. The infant presented convulsions, anaemia, renal failure and haematuria. The main treatment consisted in administration of adrenaline. Systematic and early administration of this drug has limited the severe clinical picture despite massive attack.

Adrenergic Agonists↗
PubMed2005

The Africanized honey bee dispersal: a mathematical zoom.

A general mathematical model for population dispersal featuring long range taxis is presented and exemplified by the dispersal episode of the Africanized honey bees (Apis mellifera adansonii) throughout the American Continent. The mathematical model is a discrete-time and nonlocal model represented by an integrodifference recursion. A new taxis concept is defined and introduced into the mathematical model by an appropriate modification of the redistribution kernel. The model is capable of predicting the natural barrier for the expansion of the Africanized honey bees in the southern part of the Continent due to low winter temperatures. It also describes a sensitive expansion velocity with respect to the quality of resources, which can explain the AHB's astounding spread rate, by using two different kinds of population dynamics strategies, one for a resourceful environment and the other for poor regions.

Africa↗
PubMed2006

Chill sensitivity of honey bee, Apis mellifera, embryos.

Improved methods for preservation of honey bee, Apis mellifera L., germplasm would be very welcome to beekeeping industry queen breeders. The introduction of two parasites and the emergence of an antibiotic resistant disease have increased demands for resistant stock. Techniques for artificial insemination of queens are available, and semen has been cryopreserved with limited success. However, cryopreservation of embryos for rearing queens would mesh well with current practices and also provide drones (haploid males). Eggs at five ages between twenty-four hours and sixty-two hours were exposed to 0, -6.6, and/or -15 degrees C for various times, and successful hatch measured. Honey bee embryos show chill sensitivity as do other insect embryos, and the rate of chill injury increases dramatically with decrease in holding temperature. The 48 h embryos in both groups showed the greatest tolerance to chilling, although 44 h embryos were only slightly less so.

Animal Husbandry↗
PubMed2004

Nocturnal vision: bees in the dark.

Some eyes work better in the dark than others. The apposition type of compound eye that bees and other diurnal insects possess is usually of little use after nightfall. Nevertheless some tropical sweat bees have pushed the limits of this unfavourable design so far that they can navigate using landmarks that are too dim for humans to make out.

Animals↗
PubMed2004

Honey bee (Apis mellifera) transferrin-gene structure and the role of ecdysteroids in the developmental regulation of its expression.

Social life is prone to invasion by microorganisms, and binding of ferric ions by transferrin is an efficient strategy to restrict their access to iron. In this study, we isolated cDNA and genomic clones encoding an Apis mellifera transferrin (AmTRF) gene. It has an open reading frame (ORF) of 2136 bp spread over nine exons. The deduced protein sequence comprises 686 amino acid residues plus a 26 residues signal sequence, giving a predicted molecular mass of 76 kDa. Comparison of the deduced AmTRF amino acid sequence with known insect transferrins revealed significant similarity extending over the entire sequence. It clusters with monoferric transferrins, with which it shares putative iron-binding residues in the N-terminal lobe. In a functional analysis of AmTRF expression in honey bee development, we monitored its expression profile in the larval and pupal stages. The negative regulation of AmTRF by ecdysteroids deduced from the developmental expression profile was confirmed by experimental treatment of spinning-stage honey bee larvae with 20-hydroxyecdysone, and of fourth instar-larvae with juvenile hormone. A juvenile hormone application to spinning-stage larvae, in contrast, had only a minor effect on AmTRF transcript levels. This is the first study implicating ecdysteroids in the developmental regulation of transferrin expression in an insect species.

Amino Acid Sequence↗
PubMed2004

Phenoloxidase activity in Apis mellifera honey bee pupae, and ecdysteroid-dependent expression of the prophenoloxidase mRNA.

Phenoloxidase (monophenol, l-dopa: oxygen oxidoreductase, EC 1.14.18.1) is a multicopper oxidase, which plays an important role in melanin synthesis, necessary for defense against intruding microorganisms and parasites, wound healing and cuticle pigmentation. A phenoloxidase from the hemolymph of honey bee pupae exhibited an apparent molecular mass of 70 kDa, as estimated by gel filtration and SDS-PAGE. Optimal pH and temperature were 6.5 and 20 degrees C, respectively. Activity was fully stable for 30 min at 50 degrees C. Like phenoloxidases from the hemolymph of other insects, the honey bee enzyme was activated by trypsin and inhibited by protease inhibitors and phenylthiourea. Only high concentrations of sodium azide effectively inhibited the detected activity. A low concentration (5 microM) of Ca2+, Mg2+, and Mn2+ had a stimulatory effect on the activity. Single Michaelis-Menten curves were observed for l-dopa and dopamine oxidation, but the affinity of the enzyme for dopamine was greater than for L-dopa. Semiquantitative RT-PCR and Southern blot analysis using a 359 bp labeled probe, and quantification of the prophenoloxidase mRNA levels by real-time PCR showed increased amounts of transcripts in hemocytes and integument from young pupae injected with 20-hydroxyecdysone.

Animals↗
PubMed2006

Chemosensory proteins in the honey bee: Insights from the annotated genome, comparative analyses and expressional profiling.

Small chemosensory proteins (CSPs) belong to a conserved, but poorly understood protein family that has been implicated in transporting chemical stimuli within insect sensilla. However, their expression patterns suggest that these molecules are also critical for other functions including early development. Here we used both bioinformatics and experimental approaches to characterize the CSP gene family in a social insect, the Western honey bee Apis mellifera, and then compared its members to CSPs in other arthropods. The number of CSPs in the honey bee genome (six) is similar to that found in the sequenced dipteran species (four-seven), but is much lower than the number of CSPs in the moth or in the beetle (around 20 each). These differences seem to be the result of lineage specific expansions. Our analysis of CSPs in a number of arthropods reveals a conserved gene family found in both Mandibulates and Chelicerates. Expressional profiling in diverse tissues and throughout development reveals broader than expected patterns of expression with none of the CSPs restricted to the antennae and one found only in the queen ovaries and in embryos. We conclude that CSPs are multifunctional context-dependent proteins involved in diverse cellular processes ranging from embryonic development to chemosensory signal transduction. Some CSPs may function in cuticle synthesis, consistent with their evolutionary origins in the arthropods.

Amino Acid Sequence↗