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PubMed1995

Significance of Africanized bees for public health. A review.

Although massive sting attacks by Africanized bees are currently rare, this type of bee is now endemic in parts of Arizona and Texas, and will probably spread to other warm climate areas in the United States. Treatment of severe toxic reactions to multiple stings usually includes management of shock, hypoxia, and other effects of organ damage. New approaches to reduce blood levels of venom including production of a bee antivenom and hemodialysis require further study. Patients with a trivial allergy to single stings could be at risk from systemic anaphylaxis to multiple bee sting. Those who wish to remain in endemic areas in spite of histories of systemic anaphylaxis to bee stings should be treated with venom immunotherapy, possibly administered more intensively and for longer periods than currently recommended. Continued public education is needed to limit contact with aggressive Africanized bee colonies.

Anaphylaxis↗
PubMed2002

Ecdysteroid titers in pupae of highly social bees relate to distinct modes of caste development.

Modifications in endocrine programs are common mechanisms that generate alternative phenotypes. In order to understand how such changes may have evolved, we analyzed the pupal ecdysteroid titers in two closely related, highly social bees: the honey bee, Apis mellifera, and a stingless bee, Melipona quadrifasciata. In both species, the ecdysteroid titers in queens reached their peak levels earlier than in workers. Titer levels at peak maxima did not differ for the honey bee castes, but in Melipona they were twofold higher in queens than in workers. During the second half of pupal development, when the ecdysteroid titers decrease and the cuticle progressively melanizes, the titer in honey bee queens remained higher than in workers, while the reverse situation was observed in Melipona. Application of the juvenile hormone analog Pyriproxyfen((R)) to spinning-stage larvae of Melipona induced queen development. Endocrinologically this was manifest in a queen-like profile of the pupal ecdysteroid titer. Comparing these data with previous results on preimaginal hormone titers in another stingless bee, we conclude that the timing and height of the pupal ecdysteroid peak may depend on the nature of the specific stimuli that initially trigger diverging queen/worker development. In contrast, the interspecific differences in the late pupal ecdysteroid titer profiles mainly seem to be related to caste-specific programs in tissue differentiation, including cuticle pigmentation.

Journal Article↗
PubMed1995

Melittin synthesis in the venom system of the honey bee (Apis mellifera L.).

The amount of melittin (measured by a direct hemolytic assay) contained in the venom system of single honey bees (Apis mellifera), of known age, increases from the time of eclosion to an age of about 4 weeks when about 500 micrograms of melittin is present. In older bees (5-6 weeks) the melittin level falls to about 250 micrograms. Measurements of the incorporation of [3H]leucine (injected into the haemolymph) into melittin show that melittin synthesis is most active in bees aged between 1 and 2 weeks after eclosion. The melittin content of the venom system changes as the summer progresses. Melittin levels in a bee of any age greater than 1 week are lower in mid-August than in a bee of the same age in early June.

Animals↗
PubMed2007

Towards abolition of immunogenic structures in insect cells: characterization of a honey-bee (Apis mellifera) multi-gene family reveals both an allergy-related core alpha1,3-fucosyltransferase and the first insect Lewis-histo-blood-group-related antigen-synthesizing enzyme.

Glycoproteins from honey-bee (Apis mellifera), such as phospholipase A2 and hyaluronidase, are well-known major bee-venom allergens. They carry N-linked oligosaccharide structures with two types of alpha1,3-fucosylation: the modification by alpha1,3-fucose of the innermost core GlcNAc, which constitutes an epitope recognized by IgE from some bee-venom-allergic patients, and an antennal Lewis-like GalNAcbeta1,4(Fucalpha1,3)GlcNAc moiety. We now report the cloning and expression of two cDNAs encoding the relevant active alpha1,3-FucTs (alpha1,3-fucosyltransferases). The first sequence, closest to that of fruitfly (Drosophila melanogaster) FucTA, was found to be a core alpha1,3-FucT (EC 2.4.1.214), as judged by several enzyme and biochemical assays. The second cDNA encoded an enzyme, most related to Drosophila FucTC, that was shown to be capable of generating the Le(x) [Galbeta1-4(Fucalpha1-3)GlcNAc] epitope in vitro and is the first Lewis-type alpha1,3-FucT (EC 2.4.1.152) to be described in insects. The transcription levels of these two genes in various tissues were examined: FucTA was found to be predominantly expressed in the brain tissue and venom glands, whereas FucTC transcripts were detected at highest levels in venom and hypopharyngeal glands. Very low expression of a third homologue of unknown function, FucTB, was also observed in various tissues. The characterization of these honey-bee gene products not only accounts for the observed alpha1,3-fucosylation of bee-venom glycoproteins, but is expected to aid the identification and subsequent down-regulation of the FucTs in insect cell lines of biotechnological importance.

Allergens↗
PubMed1995

Clinical symptoms and immunologic reactivity to bee and wasp stings in beekeepers.

We compared the history of sting reactions with venom skin prick test (SPT) and CAP RAST reactions in beekeepers in order to assess the value of structured questions and symptom backgrounds. The study population consisted of 102 beekeepers, who were 25-75 years of age. Bee and wasp venom SPT was performed with concentrations of 10, 100, and 300 micrograms/ml. The CAP Phadiatop test was used in the screening of IgE antibodies against common inhalant allergens. Forty-two beekeepers had never experienced large local or systemic reactions after a bee sting. Of the 31 subjects with a history of systemic reactions, 13 had experienced these during the previous year. A significant difference (P < 0.01) between systemic reactors and nonreactors was found in bee venom CAP and SPT (300 micrograms/ml). However, due to considerable overlap, these tests are unable to discriminate between allergic and nonallergic beekeepers. Both bee venom SPT (300 micrograms/ml) and CAP tests were positive in 65% of systemic reactors and in 34% of nonreactors (P = 0.008). Venom SPT (300 micrograms/ml) correlated significantly with CAP for both venoms. No correlation was observed between venom allergy and atopy. Clinically, the most practical concentration for evaluating bee and wasp venom sensitization by SPT proved to be 300 micrograms/ml.

Adult↗
PubMed1995

Anti-IgE autoantibodies and bee-sting allergy.

Serum anti-IgE autoantibodies (aaIgE) were investigated by dot immunobinding assay in bee-allergic patients in comparison with nonallergic beekeepers, healthy blood donors, and atopic subjects. Elevated serum levels of aaIgE--either free or combined with IgE--were found in both bee-allergic patients and atopic subjects as compared with beekeepers and healthy donors. With regard to a possible significance of aaIgE for the protective mechanism induced by specific allergen immunotherapy, we estimated aaIgE in bee-allergic patients before, during, and after bee-venom immunotherapy (BVIT) in relation to the outcome of a provocation test with a living bee (PT). During the first year of BVIT, there was no significant change in either free or combined aaIgE, but aaIgE decreased during protracted BVIT over 3-7 years. By using two monoclonal anti-IgE antibodies with different epitope specificity (Le27 and BSW17), we were able to detect two kinds of IgE/aaIgE immune complexes. Our data show that during and after BVIT the levels of one kind of IgE-aaIgE immune complex (the non-BSW17 type) tended to decrease in PT-negative patients but stayed elevated in PT-positive patients. The levels of the other kind of immune complex (the non-Le27 type) were similar in treatment failures and successfully treated patients. These data suggest that there are various kinds of aaIgE with different in vivo functions related to their epitope specificity. Some of them (non-BSW17 type) might be associated with BVIT failure.

Adult↗
PubMed1993

[Diagnosis of allergy in bee-keepers. A 1-year prospective study].

Thirty-six Danish bee-keepers were clinically investigated by means of a questionnaire before and after the bee season 1990. Their serum was assayed for IgE and IgG antibody reacting with bee venom, and skin prick tests were performed prior to the season. Thirty-six percent had previously reacted abnormally, either with a systemic reaction (SR) (25%) or a large local reaction (LLR) (11%). Retrospectively, eight of the nine bee-keepers with SR had upon re-exposure developed a normal reaction, in spite of the fact that seven of them had specific IgE and/or a positive prick test at subsequent examination. At follow up 38% of the persons who had previously had a SR reacted with a SR or a LLR on the first sting in the season. Two of eight with previous SR reacted with SR during the observation period in spite of a negative prick test and no specific IgE. Of the bee-keepers who had previously only reacted normally there were no systemic of large localised reactions during the observed period, although six showed signs of IgE-sensitization. The results confirm the problems of identifying patients where immunotherapy is superfluous in the group with previous SR and IgE sensitization.

Adolescent↗
PubMedDate not supplied

Mononuclear blood cell sulfidoleukotriene generation in the presence of interleukin-3 and whole blood histamine release in honey bee and yellow jacket venom allergy.

Cross-linking IgE on basophils is known to cause both sulfidoleukotriene (sLT) generation and histamine release. We recently developed an ELISA to determine sulfidoleukotriene generation by blood mononuclear cells which employs pretreatment with IL-3 to enhance leukotriene generation (cellular antigen stimulation test, CAST). Here, we compared the CAST and whole blood histamine release in response to honey bee/yellow jacket venom (BV/YJV) in 23 patients clinically suspected of type-I allergy to these venoms. Of these, 17 were diagnosed as "definitive venom allergics," defined by a positive skin test at 100 ng/ml of venom or less. The six in whom such skin reactivity was absent were labelled "suspected venom allergics." Both venoms stimulated sulfidoleukotriene generation and histamine release also from control individuals (n = 10). In patients, insect venoms generally stimulated histamine release and sulfidoleukotriene generation in excess of the mean + 3 SD of values obtained with control individuals. However, about half of the patients reacted predominantly with either histamine release or sulfidoleukotriene generation. No overall correlation was found between threshold doses necessary to stimulate sulfidoleukotriene generation (ThsLT) and histamine release (ThHist). (Linear correlation coefficients between ThsLT and ThHist were -0.02 for honey bee venom and 0.13 for yellow jacket, n = 23). Both findings are in contrast to the concept that these responses occur in parallel. From results with "definitive venom allergics," CAST sensitivity was calculated as 100% for honey bee venom and 83% for yellow jacket, and that of the histamine release assay as 62.5% for honey bee venom and 50% for yellow jacket. Specificity of the CAST was calculated as 77% for honey bee venom and 100% for yellow jacket, and that of the histamine release assay as 44% for honey bee venom and 60% for yellow jacket. Thus, CAST results are closer to skin test results than to those of the whole blood histamine release assay.

Animals↗
PubMedDate not supplied

Distribution of dopamine receptors and dopamine receptor homologs in the brain of the honey bee, Apis mellifera L.

In the brain of the honey bee, Apis mellifera, the radioligands [3H]-SCH23390 and [3H]-spiperone recognise D1- and D2-like receptors, respectively. In addition to being pharmacologically distinct and exhibiting significantly different expression profiles during the lifetime of the bee, [3H]-SCH23390- and [3H]-spiperone-binding sites differ markedly in their distribution within the brain. Estimates of [3H]-SCH23390-binding site density are highest in the somatal rind, whereas [3H]-spiperone-binding sites are most concentrated in the beta lobe neuropil of the mushroom bodies. Molecular cloning techniques have been used to identify two honey bee genes encoding dopamine receptor homologs. The first is the honey bee counterpart of a Drosophila D1-like dopamine receptor and is expressed in the mushroom bodies of both workers and drones. The second is related to D2-like dopamine receptors from vertebrates and is expressed in the brain of the bee, but the precise distribution of expression is not yet known.

Animals↗
PubMed1988

Exposure scheme separates effects of electric shock and electric field for honey bees, Apis mellifera L.

Mechanisms to explain disturbance of honey bee colonies under a 765-kV, 60-Hz transmission line [electric (E) field = 7 kV/m] fall into two categories: direct bee perception of enhanced in-hive E fields, and perception of shock from induced currents. The same adverse biological effects previously observed in honey bee colonies exposed under a 765-kV transmission line can be reproduced by exposing worker bees to shock or E field within elongated hive entranceways (= tunnels). Exposure to intense E field caused disturbance only if bees were in contact with a conductive substrate. E-field and shock exposure can be separated and precisely defined within tunnels, eliminating dosimetric vagaries that occur when entire hives are exposed to E field.

Animals↗
PubMed2003

Wind tunnel studies on spray deposition on leaves of tree species used for windbreaks and exposure of honey bees.

A wind tunnel study was conducted to determine pesticide deposition on commonly used windbreak tree species used as spray drift barriers and associated exposure of honey bees. Although it has been known that windbreaks are effective in reducing chemical drift from agricultural applications, there is still an enormous information and data gap on details of the dependence of the mechanism on the biological materials of the barriers and on standardization of relevant assessment methods. Beneficial arthropods like honey bees are adversely affected by airborne drift of pesticides. A study was initiated by first establishing a wind tunnel to create a controlled environment for capture efficiency work. Suitable spray parameters were determined after a preliminary study to construct and develop a wind tunnel protocol. A tracer dye solution was sprayed onto the windbreak samples and honey bees located in the wind tunnel at various simulated wind speeds. Analysis of data from this work has shown that needle-like foliage of windbreak trees captures two to four times more spray than broad-leaves. In addition, it was determined that, at lower wind speeds, flying bees tend to capture slightly more spray than bees at rest.

Animals↗
PubMed2000

Modes of cell death in the hypopharyngeal gland of the honey bee (Apis mellifera l).

Different modes of cell death have been revealed in the regressing hypopharyngeal glands of worker honey bees. The hypopharyngeal gland, which is well developed in young nursing bees to produce protein for larval food, was seen to regress naturally in foraging adult worker bees. A range of techniques including histology, cytochemistry, in situ TUNEL, Annexin V and Comet assays indicated that cells within the gland demonstrate progressive symptoms of apoptosis, necrosis and a vacuolar form of programmed cell death. The latter mode of cell death did not display chromatin margination, but was accompanied by an enhanced level of autophagic and hydrolytic activity in which a cytosolic source of acid phosphatase became manifest in the extra-cisternal spaces. Normal and annexin-positive cells were found to occur in the younger nursing bees, whilst necrosis and an aberrant vacuolar type of apoptosis predominated in the older foraging bees. The relevance of these results to the classification of programmed cell death is discussed.

Acid Phosphatase↗
PubMed2000

Shape and dynamics of thermoregulating honey bee clusters.

A model of simple algorithmic "agents" acting in a discrete temperature field is used to investigate the movement of individuals in thermoregulating honey bee (Apis mellifera) clusters. Thermoregulation in over-wintering clusters is thought to be the result of individual bees attempting to regulate their own body temperatures. At ambient temperatures above 0( degrees )C, a clustering bee will move relative to its neighbours so as to put its local temperature within some ideal range. The proposed model incorporates this behaviour into an algorithm for bee agents moving on a two-dimensional lattice. Heat transport on the lattice is modelled by a discrete diffusion process. Computer simulation of this model demonstrates qualitative behaviour which agrees with that of real honey bee clusters. In particular, we observe the formation of both disc- and ring-like cluster shapes. The simulation also suggests that at lower ambient temperatures, clusters do not always have a stable shape but can oscillate between insulating rings of different sizes and densities.

Algorithms↗
PubMed1998

Absence of a protective effect of the oxime 2-PAM toward paraoxon-poisoned honey bees: acetylcholinesterase reactivation not at fault.

We investigated the failure of 2-PAM to protect honey bees against poisoning with paraoxon. The protective effect of the oxime 2-PAM against inhibition of acetylcholinesterase (AChE) by paraoxon was estimated in vitro and in vivo and was correlated with the mortality of paraoxon-treated bees. In vitro, 2-PAM protected 90% of AChE activity in the presence of paraoxon and reactivated more than 90% of inhibited AChE. Minor soluble and major membrane-bound forms of bee AChE presented about similar extents of reactivation, but the first order rate constant of reactivation (kobs) of the soluble form is threefold higher than that of the membrane-bound form. However, this difference did not significantly influence the reactivation kinetics of total AChE; the constant kobs of the membrane-bound form reflected that of total AChE. The linear kinetic profile of total AChE reactivation supported the conclusion that there was a single population of reactivatable species. The bimolecular rate constant of reactivation (kr), the dephosphorylation rate constant (k2), and the dissociation constant (Kd) were 646 M-1.min-1, 0.84 min-1 and 1. 30 mM, respectively. In vivo, administration of 2-PAM, after paraoxon exposure, induced a complete protection of AChE activity, but did not elicit any significant effect on mortality in paraoxon-treated bees. The inefficiency of 2-PAM to antagonize paraoxon-induced mortality was not changed by the administration of 2-PAM in pretreatment-therapy and in therapy treatments. These results indicated that the mortality of paraoxon-poisoned honey bees was not due to a lack of AChE reactivation.

Acetylcholinesterase↗
PubMed1981

Gluconobacters from honey bees.

Fifty-six Gluconobacter strains and one Acetobacter strain were isolated from honey bees and their environment in three different regions in Belgium and identified phenotypically. Polyacrylamide gel electrophoresis of the soluble cell proteins showed that two different types exist within the Gluconobacter isolates: strains from type A were found in samples of the three regions, whereas strains from type B were only isolated in two of the three regions. Both types could occur in bees from the same region, from several hives of one bee keeper and from one hive. Strains from type A were almost identical with collection strain G. oxydans subsp. suboxydans NCIB 9018, whereas strains from type B constituted a new protein electrophoretic type within the genus Gluconobacter. Although Gluconobacter is apparently associated with honey bees, it is not known whether it is important or required for the bees or any hive product.

Animals↗
PubMed2002

Hot spots in the bee hive.

Honeybee colonies (Apis mellifera) maintain temperatures of 35-36 degrees C in their brood nest because the brood needs high and constant temperature conditions for optimal development. We show that incubation of the brood at the level of individual honeybees is done by worker bees performing a particular and not yet specified behaviour: such bees raise the brood temperature by pressing their warm thoraces firmly onto caps under which the pupae develop. The bees stay motionless in a characteristic posture and have significantly higher thoracic temperatures than bees not assuming this posture in the brood area. The surface of the brood caps against which warm bees had pressed their thorax were up to 3.2 degrees C warmer than the surrounding area, confirming that effective thermal transfer had taken place.

Animals↗
PubMed2003

The effect of queen pheromones on worker honey bee ovary development.

We report results that address a long-standing controversy in honey bee biology, the identity of the queen-produced compounds that inhibit worker honey bee ovary development. As the honey bee is the only organism for which identities have been proposed for any pheromone that regulates reproduction, the resolution of its identity is of broad significance. We examined the effects of synthetic honey bee queen mandibular pheromone (QMP), four newly identified queen retinue pheromone components, and whole-queen extracts on the ovary development of caged worker bees. The newly identified compounds did not inhibit worker ovary development alone, nor did they improve the efficacy of QMP when applied in combination. QMP was as effective as queen extracts at ovary regulation. Caged workers in the QMP and queen extract treatments had better developed ovaries than did workers remaining in queenright colonies. We conclude that QMP is responsible for the ovary-regulating pheromonal capability of queens from European-derived Apis mellifera subspecies.

Animals↗
PubMed2004

Predatory behavior in a necrophagous bee Trigona hypogea (Hymenoptera; Apidae, Meliponini).

Although most bees feed on nectar and pollen, several exceptions have been reported. The strangest of all is the habit found in some neotropical stingless bees, which have completely replaced pollen-eating by eating animal protein from corpses. For more than 20 years, it was believed that carrion was the only protein source for these bees. We report that these bees feed not only off dead animals, but on the living brood of social wasps and possibly other similar sources. Using well developed prey location and foraging behaviors, necrophagous bees discover recently abandoned wasps' nests and, within a few hours, prey upon all immatures found there.

Animals↗