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S Camazine

Publications and source records attributed to S Camazine.

8 recordsLinked to original sources
PubMed2001

Mite not make it home: tracheal mites reduce the safety margin for oxygen delivery of flying honeybees.

Many physiological systems appear to have safety margins, with excess capacity relative to normal functional needs, but the significance of such excess capacity remains controversial. In this study, we investigate the effects of parasitic tracheal mites (Acarapis woodi) on the safety margin for oxygen delivery and flight performance of honeybees. Tracheal mites did not affect the flight metabolic rate of honeybees in normoxic (21% oxygen) or hyperoxic (40% oxygen) air, but did reduce their metabolic rate relative to uninfected bees when flying in hypoxic air (5 or 10% oxygen), demonstrating that mites reduced the safety margin for tracheal oxygen delivery. The negative effects of mites on flight metabolic rate in hypoxic atmospheres were graded with the number of mites per trachea. For example, in 10% oxygen atmospheres, flight metabolic rate was reduced by 20% by moderate mite infection and by 40% by severe mite infection. Thus, the safety margin for oxygen delivery in honeybees allows them to retain normal flight metabolic rate and behavior despite tracheal mite infection under most conditions. However, the reduction in tracheal gas-exchange capacity may constrain activities requiring the highest metabolic rates, such as flying in cool weather. In support of this hypothesis, bees that were unable to return to the hive during late-winter flights showed significantly higher levels of mite infection than bees that returned safely.

Animals↗
PubMed1999

Self-organized defensive behavior in honeybees.

We investigated the defensive behavior of honeybees under controlled experimental conditions. During an attack on two identical targets, the spatial distribution of stings varied as a function of the total number of stings, evincing the classic "pitchfork bifurcation" phenomenon of nonlinear dynamics. The experimental results support a model of defensive behavior based on a self-organizing mechanism. The model helps to explain several of the characteristic features of the honeybee defensive response: (i) the ability of the colony to localize and focus its attack, (ii) the strong variability between different hives in the intensity of attack, as well as (iii) the variability observed within the same hive, and (iv) the ability of the colony to amplify small differences between the targets.

Journal Article↗
PubMed1999

Mass envenomations by honey bees and wasps.

Stinging events involving honey bees and wasps are rare; most deaths or clinically important incidents involve very few stings (< 10) and anaphylactic shock. However, mass stinging events can prove life-threatening via the toxic action of the venom when injected in large amounts. With the advent of the Africanized honey bee in the southwestern United States and its potential for further spread, mass envenomation incidents will increase. Here we review the literature on mass stinging events involving honey bees and wasps (i.e., yellowjackets, wasps, and hornets). Despite different venom composition in the two insect groups, both may cause systemic damage and involve hemolysis, rhabdomyolysis, and acute renal failure. Victim death may occur due to renal failure or cardiac complications. With supportive care, however, most victims should be able to survive attacks from hundreds of wasps or approximately 1000 honey bees.

Anaphylaxis↗
PubMed1996

Removing bee stings.

BACKGROUND: Conventional advice on immediate treatment of honey-bee stings has emphasised that the sting should be scraped off, never pinched. The morphology of the sting suggested little basis for this advice, which is likely to slow down removal of the sting. METHODS: The response to honey-bee stings was assayed with a measurement of the size of the resulting weal. Injection of known quantities of venom showed that this measurement is a good indicator of envenomisation. FINDINGS: Weal size, and thus envenomisation, increased as the time from stinging to removal of the sting increased, even within a few seconds. There was no difference in response between stings scraped or pinched off after 2 s. INTERPRETATION: These data suggest that advice to patients on the immediate treatment of bee stings should emphasise quick removal, without concern for the method of removal.

Animals↗
PubMed1983

Spider leg autotomy induced by prey venom injection: An adaptive response to "pain"?

Field observations showed orb-weaving spiders (Argiope spp.) to undergo leg autotomy if they are stung in a leg by venomous insect prey (Phymata fasciata). The response occurs within seconds, before the venom can take lethal action by spread to the body of the spiders. Autotomy is induced also by honeybee venom and wasp venom, as well as by several venom components (serotonin, histamine, phospholipase A(2), melittin) known to be responsible for the pain characteristically elicited by venom injection in humans. The sensing mechanism by which spiders detect injected harmful chemicals such as venoms therefore may be fundamentally similar to the one in humans that is coupled with the perception of pain.

Journal Article↗
PubMed1980

A study of the medical ethnobotany of the Zuni Indians of New Mexico.

This paper examines the medical ethnobotany of the Zuni Indians of west-central New Mexico. Historically, these people were hunters and gatherers, and later, farmers and sheepherders. They developed an extensive knowledge of the local flora and a complex religious rite and system of medical practice. Now, as customs and values of Western societies encroach upon their lifestyle, the Zuni's knowledge of the medicinal use of plants is in danger of being forgotten. Field work conducted during the summers of 1977 and 1978 with the Zuni involved interviews with 27 Zuni medicine men and elders and the collection of 138 plant species. For 49 species a medicinal use was described. These remedies were examined in detail to determine their pharmacological and physiological action and their cultural significance. A total of 31 medicinal plants collected in this study were not mentioned in the Zuni ethnobotanical study by Stevenson over 60 years earlier. This may reflect a difficulty in recording all the plant remedies of a culture rather than an acquisition of new remedies since that time. The use of herbal remedies today and the knowledge of their use in the past has diminished.

Cough↗