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At least 703 records · Page 39Linked to original sources
PubMed1983

[Bee mite: Varroa jacobsoni qudemans].

Varroatosis caused by varroa jacobsoni on honeybee, Apis mellifera L., is currently one of the worlds major bee keeping problems. The mite parasites the adult honey bee, as well as its developmental stages, by sucking the insects's haemolymph. Up to date, many chemicals were used against this mite but still there is no chemical which has 100% effect and at the same time bees and their brood demonstrate a good tolerance. The investigations on biology and therapy on Varroa are still going on in many countries.

Bees↗
PubMed1981

The estimation of bee venom specific human IgG.

Bee venom specific human IgG was measured by solid phase sandwich radioimmunoassay (RIA) using bee venom adsorbed to polystyrene tubes. RIA results were found to correlate with those obtained in an enzyme immunoassay (EIA) for bee venom specific IgG. The RIA did not suffer from the high background often associated with other solid phase radioimmunoassays for human IgG. Furthermore, both the RIA and EIA were simple to perform, inexpensive and highly reproducible.

Absorption↗
PubMed1978

Honey bee venom allergy immunological studies of systemic and large local reactions.

The IgE and IgG antibody responses to four allergen fractions of honey bee venom were studied in 13 sera from patients who experienced systemic reactions from bee stings and eight from those who experienced large locals. Both groups were similar in allergen response. IgE and IgG levels and ratios. A significant number of patients were found to have experienced both types of reactions from bee stings. It is proposed that IgE antibody positive systemic and large local reactions are both IgE mediated allergic reactions. The determining factors for reaction type include venom dose and sting site.

Adolescent↗
PubMed1978

[Clinical picture and diagnosis of bee-venom allergy. A comparison between skin tests and RAST determinations].

Of a group of 53 anamnestically assured bee venom allergies 81.1% positive skin tests (bee whole body extract) as well as 79% positive RAST (bee venom) could be proven. A statistical connection between skin test and clinic reaction degree, as well as between "RAST-clinic reaction degree" and "skin test--RAST" could not be found. The agreement between skin test and RAST results was of 71.7%, the positive correlation of 66%. The problem of the diagnosis and the therapy of allergy to hymenopteren stings is briefly described.

Bees↗
PubMed1981

[Effect of phospholipase A2 from the venoms of bee and Middle Asian cobra on choline uptake by synaptosomes].

The effect of purified phospholipase A2 from venom of the bee Apis mellifica and from venom of the cobra Naja naja oxiana on the Na+-dependent high affinity choline transport into the synaptosomes of rabbit corpus striatum (active uptake) was studied. Both phospholipases A2 were shown to inhibit the active choline uptake by the synaptosomes. The bee venom phospholipase at a concentration of 10(-8) M and the cobra venom phospholipase at a concentration of 10(-6) M produced a 50% inhibition of choline uptake. A relationship was found between the enzymatic activity of the phospholipases and their ability to block choline uptake by the synaptosomes. A removal of Ca-ions from the medium abolished the effects of both phospholipases. Replacement of Ca2+ by Sr2+ inhibited the effect of the cobra venom phospholipases but did not inhibit that of bee venom enzyme.

Animals↗
PubMed1995

[Change in erythrocyte volume and spectrum of membrane proteins induced by melittin, phospholipase A2 and bee venom].

Human erythrocytes and erythrocyte ghost membranes were treated with melittin (M), phospholipase A2 (PLA2) and whole bee venom. Treatment by whole bee venom or M + PLA2 resulted in a significant decrease of the cell volume, cell spherulation and hemolysis. Used separately, M produced an increase in the cell volume during hemolysis, while treatment with PLA2 stimulated M-induced hemolysis without any effect on the cell shape or volume even at relatively high concentrations. Combined action of M and other agents revealed: stimulation of M-induced hemolysis by Triton X-100 used at concentrations by two orders of magnitude lower than lytic concentrations; saponin acted similarly but at concentrations closer to those known to lyse cells: chlorpromazine inhibited the hemolysis at sublytic concentrations. The effects of these agents on M-induced hemolysis was unaccompanied by a decrease in the cell volume. Erythrocytes or ghosts treated with M + PLA2 or bee venom showed altered SDS-electrophoretic protein patterns: bands 6 and 8 were markedly reduced, while new bands of relatively low molecular weights were identified. The absence of volume or protein pattern changes during detergent-stimulated M-induced hemolysis points to the specificity of M-membrane interactions in the presence of PLA2.

Bee Venoms↗
PubMed1993

T cell epitope specificity in human allergic and nonallergic subjects to bee venom phospholipase A2.

Phospholipase A2 (PLA) is a biochemically fully defined glycoprotein, representing the main allergen of bee venom. We have established CD4+ T cell clones specific to PLA from subjects allergic and nonallergic to bee sting. By screening the epitope specificity of these clones with 62 synthetic overlapping dodecapeptides representing the PLA molecule, two immunogenic epitopes, PLA81-92 and PLA113-124, were identified. Additional screening, using longer peptides of up to 18 residues, revealed a third epitope at position PLA 45-62. These epitopes are recognized by specific T cell clones in association with HLA-DP and -DQ molecules, although HLA-DR-associated responses to PLA exist. Primary in vitro proliferation of unfractionated PBMC from bee sting allergic, hyposensitized, or hyperimmune subjects to PLA-derived peptides revealed the same immunogenic sites as found in the T cell clones. Among the different groups of individuals, proliferative responses to the PLA molecule and fragments thereof were generally higher in allergic patients than in nonallergic subjects. Thus, at least three linear epitopes are involved in T cell recognition of PLA, independently whether or not subjects are allergic.

Amino Acid Sequence↗
PubMed1995

Bee venom immunotherapy results in decrease of IL-4 and IL-5 and increase of IFN-gamma secretion in specific allergen-stimulated T cell cultures.

The mechanisms of bee venom immunotherapy (VIT) are largely unknown. The aim of this study was to follow the changes of T cell cytokine secretion during the course of VIT. Ten bee venom-allergic patients with a history of severe systemic reactions, positive skin tests, and bee venom (BV)-specific serum IgE Abs were treated as follows: on the first day, a cumulative dose of 111 micrograms, starting with 0.1 microgram, was administered s.c. under intensive care conditions. Further injections of 100 micrograms BV were given on day 7, day 21, and thereafter at intervals of 4 wk. Blood samples were obtained just before the initiation of VIT, after the last injection on the same day, and before the subsequent BV injections on days 7, 21, and 50 of VIT. Peripheral blood mononuclear cells (PBMC) were stimulated with phospholipase A (PLA), the major BV allergen, or with a control Ag tetanus toxoid (TT). Cytokine secretion was measured 24 h after restimulation of the cultures with solid-phase bound OKT3 F(ab')2 mAbs after 7 days of culture. In PLA-stimulated cultures, VIT resulted in decreased IL-4 and IL-5 and increased IFN-gamma secretion. In TT-stimulated cultures, we observed similar levels of cytokines before and during VIT. We conclude that ultra-rush VIT changes allergen-specific T cell reactivity.

Allergens↗
PubMedDate not supplied

Biochemical properties and study of antigenic cross-reactivity between Africanized honey bee and wasp venom.

Africanized honey bees and the wasp Polistes versicolor are common insects in Brazil; their venoms are composed of a complex mixture of components which present several biological activities. Stinging accidents are very frequent and are generally followed by important clinical reactions, and even deaths are not uncommon. In the present study, venom was extracted from Africanized honey bees and P. versicolor, and it was biochemically characterized and the antigenic cross-reactivity was investigated by Western blot analysis and specific IgE determination by ELISA in the sera of subjects allergic to each venom. The honey bee venom presented higher phospholipase A2 and hyaluronidase activities than P. versicolor venom, which in turn presented higher lipase, acid phosphatase and esterase activities. A high incidence of false-negatives was also observed during determinations of specific IgE for P. versicolor venom when the kits with venoms from wasps of temperate climates were used, suggesting that the diagnosis of allergy to neotropical wasp venom must take into consideration the clinical history and skin tests.

Adolescent↗
PubMed1993

[The effect of Varroa jacobsoni invasion on bee colonies with queens of different breeds in the fourth year of the disease].

The objective of the work was to determine the effect of invasion of Varroa jacobsoni on the bee colonies of different breeds in the fourth year of varrosis. It was found out that bee colonies which were not treated died in the fourth year of the disease, while treated ones were debilitated. The main loss concerned the bee colonies with augustonian and carnica queens. The most resistant were colonies with caucasian queens.

Animals↗
PubMed1996

Bee head acetylcholinesterase as an indicator of exposure to organophosphate and carbamate insecticides.

Insect acetylcholinesterase has received special attention following the discovery that inhibition of the enzyme is the mechanism of activity of the organophosphate and carbamate insecticides. Apiculture is an important source of Greek income and as the detection of anticholinesterase insecticides in bees is very difficult, investigation of the cause of death of honeybees due to acetylcholinesterase inhibition is of great value and will contribute to the differential diagnosis of bee diseases. The enzymatic assay is not capable of distinguishing between individual pesticides', but is an indicator of the exposure of bees to anticholinesterase insecticides.

Animals↗
PubMed1997

Bee venom-induced shrinkage of erythrocyte ghosts.

When hemolysis of erythrocyte ghosts is induced by bee venom, their volume becomes significantly less than the initial volume of the cells. Treating isolated ghost membranes with bee venom has the same effect. An analogous phenomenon is caused by a mixture of purified melittin and phospholipase A2, but not by the separate action of these substances. The volume changes develop non-monotonously in time. A prolonged phase of spontaneous volume restoration follows the initial phase of shrinkage. Inhibitors of melittin-induced hemolysis (Mg2+, chlorpromazine) retarded the development of both shrinkage and restoration phases, but did not influence the extent of the volume changes. High concentrations of Ca2+ (10 mM) acted in a similar manner, but increased the extent of shrinkage at low concentration (0.1 mM). The extent of shrinkage was increased several-fold in isotonic nonelectrolyte solutions. Analysis of the data shows that bee venom-induced reduction in ghost volume is not due to osmotic effects or permeabilization and/or fragmentation of the membrane, but rather is attributed to membrane contraction, which presumably relates to the membrane cytoskeleton. In this respect venom-induced shrinkage resembles that of contractile events in non-muscle cells.

Bee Venoms↗
PubMed1997

Activity-dependent changes to the brain and behavior of the honey bee, Apis mellifera (L.).

To explore the origins and possible behavioral consequences of structural plasticity in an insect brain, we have taken advantage of the following: (1) the highly compartmentalized nature of the primary antenno-sensory centers (antennal lobes) of the brain, (2) the ease with which individual compartments, or glomeruli, within the antennal-lobe neuropil can be identified, and (3) the predictability of changes to readily identifiable glomeruli in the antennal lobes of the adult worker honey bee. Treatment with the juvenile hormone analog methoprene and hive manipulation techniques are used to induce precocious foraging behavior in young worker honey bees. The impact of these treatments on the ontogeny of olfactory learning performance and on the volumes of readily identifiable glomeruli in the antennal lobes of the bee brain are examined in parallel. The study reveals that (1) significant changes in glomerular volume are activity dependent and (2) associative learning of floral odors improves with experience. Improvements in associative learning performance coincide temporally with increases in glomerular volume. This raises an important question: are changes in glomerular volume that result from shifts in behavior simply a consequence of changes in the use of peripheral sensory pathways, or are they associated with events that underlie learning and the formation of long-term memories?

Animals↗
PubMed1997

[Risk of disseminating apiary diseases by international movements of bees and their products].

The evaluation of the risks of spreading bee diseases is based on information obtained from a wide variety of sources: reports of the world distribution of pathogenic agents; trade flow in bees and bee products; and observations and experimental data on the diseases. At present, this information is severely lacking and only enables a brief outline of trends to be made. Current data are inadequate to prevent the spread of diseases from one country to another. To improve this situation, it is important that exporting countries establish epidemiological and health surveillance practices based on harmonised procedures and diagnostic tests. In addition, the products of apiculture should be given a permanent, specific nomenclature, drawn up by the World Trade Organisation.

Animals↗
PubMedDate not supplied

[Effect of bee venom and its components on electrophoretic mobility of erythrocytes].

The change of electrophoretic mobility (EPM) of erythrocytes of donor blood caused by their incubations with the bee venom and its major components--melittin and phospholipase A2 was investigated. It was estimated that the bee venom reversibly decreased EPM of erythrocytes to the higher degree than its separate components. The reaction was completely abolished after preliminary processing of erythrocytes with neuroaminidase and partly after their processing with glutaraldehyde, but the effect of EPM increased under the conditions of the increasing of ATP concentration. Proceeding from the authors' data it was concluded that the major components of the bee venom successively interacted with glicocalyx elements and membrane of erythrocytes which evokes the charge redistribution in these blood cells.

Adenosine Triphosphate↗
PubMed1964

BEE VENOM TOLERANCE IN WHITE MICE IN RELATION TO DIET.

In white mice the consumption of a high protein diet either just before, or over a period of 3 days prior to, the injection of venom from the honey bee Apis mellifera L. markedly increases the number of deaths. Conversely, a period of starvation or a nonprotein diet fed to white mice for 3 days prior to the injection of bee venom significantly reduces the number of deaths.

Animals↗
PubMed1998

Comb wax effects on the ontogeny of honey bee nestmate recognition

We addressed the general question of how kin recognition cues develop by investigating cue differentiation between colonies of the honey bee, Apis mellifera. In honey bee colonies, exposure to the wax comb is a critical component of the development of kin recognition cues. In this study, we determined how the cues develop under natural conditions (in swarms), whether the genetic source and age of the wax affect cue ontogeny, and whether exposure to wax, as in normal development, affects preferential feeding among bees within social groups. Cue development in swarms coincided with wax production, rather than with the presence of brood or the emergence of new workers; this finding supported previous observations concerning the importance of wax in cue ontogeny. Effective cue development required a match between the genetic source of the workers attempting to enter the hive, the wax to which they were exposed, and the guards at the hive entrance. The wax must also have been exposed to the hive environment for some time. Cues gained from wax did not mask or override cues used in preferential feeding interactions; this finding supports the contention that two recognition systems, one for nestmate recognition and the other for intra-colonial recognition, are present. The results fit a general model for cue development in nestmate recognition that relies on the use of nesting materials as an intermediary; the evolutionary significance of this model is discussed. Copyright 1998 The Association for the Study of Animal Behaviour.

Journal Article↗
PubMed2001

Individually recognizable scent marks on flowers made by a solitary bee.

The marking of flowers with ephemeral scent is an underappreciated but vital element in the foraging behaviour of social bees. Using observational and experimental data, we tested whether a solitary bee (female Anthophora plumipes) uses scent marking while foraging on flowers of Cerinthe major in Portugal. Females used scent marks with at least two components that differed in their volatility and, furthermore, recognized the marks of different individuals. A very short-term component (<3 min) was attractive, resulting in the observed high level of immediate revisits: this component appeared to be adjusted according to the foraging needs of the moment. A longer-term component (<30 min) was initially repellent and matched the rate of nectar renewal; it, or the response to it, also appeared to be adjusted to the perceived level of nectar reward. There may be even longer-term effects associated with the specific foraging areas of individual bees. Observed differences in the way in which individuals responded to scent marks indicate that they may play a role as part of a dominance or exclusion mechanism among females. Copyright 2001 The Association for the Study of Animal Behaviour.

Journal Article↗