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At least 19 recordsLinked to original sources
PubMed1976

Imported fire ant hypersensitivity. Studies of human reactions to fire ant venom.

It is now apparent that venom and venom components of the Hymenoptera superfamilies of Apida (honeybee) and Vespida (wasps, yellow jackets, and hornets) are becoming increasingly important in the diagnosis and treatment of hypersensitivity reactions. Stings from fire ants (superfamily Formicidae, family Myrmicinae) have also been recognized as causes of systemic reactions in man. Fire ant venom is unique in its composition, consisting mainly of alkaloids in aqueous suspension with only trace amounts of protein. This study compares the skin reactivity of fire ant venom and synthesized alkaloid components with the whole body extract (WBE) of fire ants and other Hymenoptera. The venom as well as the WBE of fire ants was found useful for skin test diagnosis of sensitive individuals. There appear to be cross-reactive or shared antigens between fire ant venom, WBE, and WBE of other Hymenoptera. Successful passive transfer of skin reactivity to nonsensitive individuals was accomplished with sera from sensitive individuals. Loss of this passive transfer by heating sera at 56 degrees C for 4 hr is evidence in favor of IgE mediating the positive skin test to the venom.

Animals↗
PubMed1992

Safety and efficacy of fire ant venom in the diagnosis of fire ant allergy.

Thirty-three adult patients who had had systemic allergic reactions to fire ant stings and 33 insect-nonallergic control subjects were skin tested with single lots of Solenopsis invicta (Sol i) fire ant venom (IFAV) and two commercially available imported fire ant whole body extracts (IFA WBEs). All three extracts were analyzed for protein concentration. Sol i II and Sol i III concentrations were each assayed by means of two ELISAs with complementary monoclonal antibodies, one species specific and one cross-reactive. Radioallergosorbent test (RAST) to IFAV and both IFA WBEs was performed on sera from all study subjects. Both IFA WBEs contained high concentrations of fire ant body proteins. Sol i II and III concentrations each varied twofold between the two IFA WBE preparations. Patients were generally more reactive to IFAV than IFA WBE by skin testing and RAST. IFAV RAST appeared to be a more sensitive assay than IFA WBE RAST. No adverse reactions occurred to skin testing with IFAV, but intradermal testing with higher concentrations of IFA WBE caused delayed large local reactions in 16 of 30 (53%) control subjects. These reactions were attributed to the large amounts of extraneous body proteins in IFA WBE. These results (1) demonstrate that skin testing with IFAV is safe, (2) indicate that IFAV is more potent than IFA WBE, and (3) suggest that IFAV may be the superior reagent for diagnosis of fire ant allergy.

Adult↗
PubMed1977

[The queen technic for ant control. I. The effect of tepa on laboratory colonies of the pharaoh ant].

The present paper discussed at the example of Tepa [Tris (1-aziridinyl) phosphine oxide] in which manner the control of pharaoh's ant in the sense of the "queen technique" with chemosterilants is possible; which points of view must be considered and which condition an acceptable substance should be fulfilled. The application of Tepa is ralized according to various techniques (e.g. dipping, baiting, tarsal contact), in the course of which the baiting technique is preferred. The influence of different concentrations in various baits on the brood, workers and queens are described. In baits with 1% of the substance a permanent sterilization could be achieved. In combination with other population depressing factors (larval and worker mortality) resulted in eradication of the colonies. The action extended also to the larvae of the sexuals, so that the queenless colonies failed in the production of new queens and males. Histological investigations showed in the females at higher concentrations distinct pathological alterations (pycnosis, vacuolizations, proliferation in the follicles epithelium); whereas the spermatogenesis in the males is decreased but not entirely suppressed. At lower concentrations only the fertility but not the fecundity was influenced. A handing-over of recessive lethal mutations to the progeny does not take place. The practical points of view for the use of chemosterilants in the control of pharaoh's ant are discussed. Whereas the low biological stability of Tepa does not exclude an introduction in the practice, the high mutagenic activity prevents an application in the field.

Animals↗
PubMed1978

Problem of behavioral plasticity in slave-making Amazon-ant Polyergus rufescens Latr. and in its slave-ants Formica fusca L. and Formica cinerea Mayr.

Changes in the natural behavior, expressing adaptation to cohabitation in a community, were observed in the slave-making ants P. rufescens and the slave-species F. fusca and F. cinerea. After a few raids, the initially undirected arousal evoked in the slaves by the amazons' raids, begins to acquire attributes appropriate to the situation, but completely different in both studied slave-species. F. cinerea picks up the pupae abandoned on the nest by the slave-making ants and eventually begins to wrench them away from the amazons arriving with prey. F. fusca, whose nests have openings so narrow that it prevents the mass entry of amazons with prey, begin to enlarge those openings shortly after the amazons return. After a certain number of raids, F. fusca begin to enlarge the openings immediately after the departure of the amazons for the slave-raid. The amazons, on their side, adjust soon to the specific behavior of the given slave-species; in nests with F. fusca, they make use of enlarged openings, carrying their prey through them into the nest; when F. cinerea are the slaves, most of the amazons begin to drop the pupae on the nest, and later even surrender the prey to the slaves who meet them. It is supposed that in all three species, under the influence of specific conditions there occurs the process of learning of new forms of behavior.

Animals↗
PubMed1979

Ant-egg cataract. A study of a family with dominantly inherited congenital (ant-egg) cataract, including a histological examination of the formed elements.

A family with "ant-egg" cataract in three generations is described. The cataract is congenital, probably of autosomal dominant inheritance. Light microscopy of the ant-eggs showed that they are made up of a peripheral zone of lens material and a large almost homogenous centre. Element analysis by X-ray spectrophotometry showed a high content of calcium and phosphorus in the centre. The cataract has been easy to operate on and the postoperative visual results have been good.

Calcium↗
PubMed1992

Pharmacological studies of jumper ant (Myrmecia pilosula) venom: evidence for the presence of histamine, and haemolytic and eicosanoid-releasing factors.

Jumper ant venom was prepared by extraction of venom sacs in distilled water and centrifugation to remove insoluble material. Jumper ant venom (2 micrograms/ml) produced a biphasic response on isolated guinea-pig ileum, i.e. an initial rapid contraction followed by a slower prolonged contraction. The histamine antagonist mepyramine (0.1 microM) inhibited the first phase of this response by greater than 90%. In the isolated rat stomach fundus strip (which is insensitive to histamine), jumper ant venom (6 micrograms/ml) produced only a single contraction. No tachyphylaxis was observed to repeated doses of jumper ant venom in guinea-pig ileum or rat fundus strip. Responses to jumper ant venom of the egg-albumin-sensitised guinea-pig ileum were not significantly different before and after an in vitro anaphylactic response induced by egg albumin (0.5 mg/ml). Fluorometric assay revealed a mean value of 0.9 +/- 0.2% of the dry weight as histamine in jumper ant venom. Both the lipoxygenase/cyclo-oxygenase inhibitor BW755C and the cyclooxygenase inhibitor indomethacin significantly inhibited the second phase response to jumper ant venom of the guinea-pig ileum, and the response of the rat fundus strip. The muscarinic receptor antagonist atropine (0.1 microM), the bradykinin antagonist [Thi5,8,D-Phe7]-bradykinin (10 microM) and the angiotensin converting enzyme inhibitor captopril (20 microM) did not affect either phase of the venom response in guinea-pig ileum. Jumper ant venom caused haemolysis of guinea-pig blood. The degree of haemolysis was significantly reduced when boiled venom was used. These results suggest that jumper ant venom contains histamine and may cause the release of cyclo-oxygenase products. It also contains a heat-sensitive haemolytic factor.

4,5-Dihydro-1-(3-(trifluoromethyl)phenyl)-1H-pyraz↗
PubMed1977

Harvester ant sensitivity: in vitro and in vivo studies using whole body extracts and venom.

Harvester ant stings by Pogonomyrmex maricopa (Pm) or Pogonomyrmex rugosus (Pr) resulted in serious reactions in 8 patients, 4 with generalized reactions and 1 with large local reactions. Exposure to one species in the genus Pogonomyrmex (P) appeared to cross-sensitize ant-sensitive patients to other species in the same genus as evidenced by skin testing and leukocyte histamine release, but these patients were less sensitive to extracts from other stinging Hymenoptera, including bee, wasp, yellow jacket, hornet, and Formica ant. Pr ant venom was obtained by electrical stimulation of live ants for leukocyte histamine release studies. The venom preparation was considerably more effective in inducing histamine release than a body extract derived from gasters, the posterior abdominal segments. Rabbits immunized with an extract from one species produced precipitating antibodies against the injected extract withich cross-reacted with extracts from other species of harvester ant, but not with other stinging Hymenoptera. Humans and rabbits appear to react to certain genus-specific antigens present in Pogonomyrmex whole body extracts. Proper identification of the offending ant is crucial for proper testing and treatment of ant-sensitive patients.

Animals↗
PubMed1992

A case of anaphylaxis by ant (Ectomomyrmex spp.) venom and measurements of specific IgE and IgG subclasses.

Hypersensitivity to the stings of the Hymenoptera has been described since antiquity. The hypersensitive reactions to insect stings vary from minor skin reactions to severe and sometimes fatal anaphylaxis. Concerns about sting hypersensitivity have been increasing because of many incidents of allergic reactions of patients to the fire ant in the southern area of the United States as well as the harvester ant in some areas. We experienced one unique case with severe allergic reactions by ant of the Ectomomyrmex spp. of the subfamily Ponerinae, which is not a harvester ant. For three years the patient had been suffering from generalized allergic reactions such as anaphylaxis after the ant stings four-five attacks in a year. We determined that her reactions were due to specific IgE mediated type I hypersensitivity by the detection of a high level of specific IgE to the ant venom in her serum. The high level of specific IgG4 to the ant venom was also noted in her serum, however, the role of ant venom IgG4 was not clearly determined.

Adult↗
PubMed1992

Susceptibility and behavioral response of red imported fire ant (Hymenoptera: Formicidae) to selected entomogenous nematodes (Rhabditida: Steinernematidae & Heterorhabditidae).

Pathogenicity of infective juveniles of selected Steinernema spp. and Heterorhabditis spp. toward developing and reproductive stages of the red imported fire ant, Solenopsis invicta Buren, was tested under laboratory conditions. At 10(3)-10(5) infective juveniles per Petri dish, mortality of reproductive larvae, pupae, and alates ranged from 28 to 100% at higher doses after 96 h at 23-25 degrees C. Steinernema carpocapsae All was the most consistent species tested; this nematode caused mortality of fire ant larvae, pupae, and alates of 82-94, 64-96, and 38-99%, respectively. Although not susceptible to nematode infection, worker ants vigorously preened nematodes from brood, alates, and themselves. In a field study, S. carpocapsae (5 x 10(6) and 2 x 10(6) drench, 2 x 10(6) infective juvenile infection) was applied to active fire ant mounds in 3.8-liter suspensions. Hydramethylnon (75 ml), a water drench, a water injection, and untreated fire ant mounds were marked and treated. Overall activity in mounds treated with nematodes of hydramethylnon ranged from 40 to 48%. Satellite mound activity accounted for 32-44% of overall activity in mounds treated with nematodes 2 wk after treatment. However, 6 wk after treatment, activity in mounds treated with hydramethylnon was 44%; activity of mounds treated with nematodes ranged from 52 to 80%. Satellite mound activity accounted for 0-24% of overall activity. Whereas a soil drench of S. carpocapsae showed potential as a control method for the red imported fire ant, colony relocation after nematode treatment could limit overall efficacy unless application techniques are developed to overcome or take advantage of the movement.

Animals↗
PubMed1975

The imported fire ant: dimensions of the urban problem.

Although the imported fire ant is a known rural problem, the problem it may pose to urban dwellers has not been documented. A telephone survey of 240 households selected by a probability sample of an upper middle class suburb of New Orleans was carried out to ascertain the experiences of residents with fire ants from June to August 1973. Overall, ant stings were reported for 29% of the study population, with sting rates of 55% among children under 10 years old. Among those stung, at least minimal allergic reactions were reported for 17%, and 4.4% required medical consultation. Of households with outdoor premises, 55% reported fire ant infestation, 86% of these used pesticides for fire ant control, and few felt that community assistance was needed for private property. Half of the respondents, however, favored a community control program for public grounds. These data may provide a basis for decision as to the need for community efforts in fire ant control.

Adolescent↗
PubMed2026

Non-reciprocal coevolution in a fungus-gardening ant.

Symbioses are often characterized by nonrandom associations between hosts and symbionts. Hosts may obtain symbionts horizontally from the environment or vertically from a parent or sometimes use both methods. Macroevolutionary examinations of fungus-gardening ants and their fungi have shown either a 1:1 coevolution model or a 'diffuse' model between ant host and fungal symbionts. However, some of these conclusions may have been based on using relatively conservative molecular markers, which could obscure cryptic variation. The use of whole genome approaches potentially offer more power in elucidating coevolutionary history. In this study, we examined patterns of coevolution in a single species (Trachymyrmex septentrionalis) using genomic and experimental approaches. We tested whether ant-fungal specificity patterns reflected either 1:1 or diffuse models of coevolution. While we report significant co-phylogenetic signal among intraspecific ant host and fungal symbiont lineages, we found evidence of 1:1 coevolution in some lineages and diffuse in others. These conclusions were supported by the results of experiments where newly mated T. septentrionalis queens were forced to grow novel fungi that suggested that not all fungi are equivalent symbionts and would require specialized hosts. Thus, within a single ant species, there is a mixed support for both models.

Animals↗
PubMed2025

Ancestral complexity and constrained diversification of the ant olfactory system.

Communication is a cornerstone of social living, allowing the exchange of information to align goals and synchronize behaviour. Ants, a group of highly successful social insects, have heightened olfactory abilities that are integral to their evolutionary success. Essential for colony cohesion and cooperation, a female-specific olfactory subsystem processes information about nestmate recognition cues (cuticular hydrocarbons), including basiconic sensilla on the antenna and a cluster of specific glomeruli in the antennal lobe. While it has often been linked to ants' social lifestyle, the evolutionary origins and phylogenetic distribution of this system remain unknown. We conducted a comparative exploration of the ant olfactory system across eight major subfamilies, integrating neuroanatomical, chemical and behavioural analyses. Our findings reveal that sophistication of the ant olfactory system has deep evolutionary roots. Moreover, antennal lobe investment is not associated with social traits such as colony size, polygyny or foraging strategies, but correlates with cuticular hydrocarbon profile complexity. Despite neuroanatomical differences, different ant species consistently excel in nestmate discrimination, indicating adaptation to chemical diversity while maintaining reliable social recognition. This suggests that cuticular hydrocarbon profile and neuronal investment in olfactory neuropil have co-evolved to sustain discrimination performance.

Animals↗
PubMed1975

Mass recruitment by army ants.

A single army ant (Ecitoninae) can attract and direct scores of workers to prey by means of a chemical trial and momentary contact between the recruiter and workers on a raid column. Recruited workers, in turn, attract more ants, resulting in a continuous stream of recruits. While the recruitment mechanism is basically similar, the speed and the number of ants recruited are greater form army ants than for other ants.

Animals↗
PubMed1975

Ethological studies in the ant Tetramorium caespitum Mayr. I. Foraging and building behavior.

Carrying heavy objects is a common element in the foraging and building behavior of ants. The initial stages of this behavior, i.e., lifting and moving in T. caespitum displayed as stereotyped patterns of movement. These patterns do not improve as the ants become older and more experienced, which suggest their congenital nature. Growing experience of ants is manifested in the later stages of the transportation of heavy objects, and especially in entering the correct opening of the nest with the carried prey. When a foraging ant leaves its nest to return to the prey it initially moves in the general direction of its objective. It is not until a certain distance from the nest is reached, that the ant is able to use olfactory stimuli to locate and follow its previous path. These observations indicate that the representatives of this species do not learn an exact way to and from the nest but instead have a memory for direction. The congenital character of these basic elements of foraging and building behavior allows the existence of a social organization without a division of work and foraging areas.

Animals↗
PubMed1976

[The effect of chlordecone (Kepone) on the laboratory colonies of the Pharaoh's ant Monomorium pharanois].

The control of the Pharaoh's ant Monomorium pharaonis is very difficult because of the social way of life in this insect pest. In regard to the reported good suppressing results of Chlordecone we analyzed the mode of action in this compound at laboratory colonies of the pharaoh's ant. Commercial gel and granular formulations as well as selfmade baits have been tested. The best results showed the granular bait on the basis of ground nut butter, while the effects of all of the others was much weaker. The pure gel, developed for cockroach control, was like the application in drinking water without success. The treatment of the colonies after a starvation period of 60 hours improved all of the effects. Sterility (fertility, fecundity) in the surviving queens was not measurable. For practical control measures the often recommended prebaiting is not at all desirable. The action on the worker ants is good, but the special mode of action based on the selective mortality in the queens and its detailed effects are unknown. Through the early absence of queens in the colonies will be induced in many cases a production of new sexuals, which compensate the success of the poison and allow the colonies to recover. The treatment leads faster to an eradiction if the ET90 to workers mortality reached earlier than that in the queens. Successful control of pharaoh's ant will Chlordecone should be considered with reserve. Nethertheless Chlordecone is in the present situation of pharaoh's ant control one of the best so far known organic-synthetically insecticides.

Animals↗
PubMed1979

Ant-egg cataract. An electron microscopic study.

The ultrastructure of the ant-egg cataractous lens has been studied. Comparison of tissue demineralized by means of EDTA with untreated tissue showed the calcium salts in the ant-eggs to be mostly crystalline. A laminar appearance of the ant-egg seen in EDTA treated material suggested an intermittent growth of the structure. In the ant-eggs, as well as in some areas separate from these, membrane limited cytoplasmic bodies could be seen in many cases, the membranes of which were partly joint and partly separated by an electron dense material. It is suggested that the calcifications seen as the ant-eggs are secondary phenomena to an abnormal metabolism, morphologically seen as membrane limited cytoplasmic bodies.

Cataract↗
PubMed2025

Transcriptional interference gates monogenic odorant receptor expression in ants.

Communication is crucial to social life, and in ants, it is mediated primarily through olfaction. Ants have more odorant receptor (OR) genes than any other group of insects, generated through tandem duplications that produce large genomic arrays of related genes. The mechanism by which olfactory sensory neurons (OSNs) produce a single functional OR from these arrays remains unclear. In ant OSNs, only mRNA from one OR in an array is exported into the cytoplasm, while upstream genes are silent and transcripts from downstream genes remain nuclear. Here, we show that readthrough transcription in the downstream direction generates non-translated transcripts. We also find that OR promoters are bidirectional, producing antisense long non-coding RNAs. We suspect that neither readthrough nor antisense transcription produces functional RNA but that bidirectional transcription alone is critical to suppressing the expression of all other OR genes in a tandem array. Finally, we present evidence that this regulatory architecture is conserved across ants and bees, suggesting that this mechanism for functionally monogenic OR expression is widespread in insects with expanded OR repertoires.

Animals↗