Field evaluation of picaridin repellents reveals differences in repellent sensitivity between Southeast Asian vectors of malaria and arboviruses.

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Van Roey, Karel; Sokny, Mao; Denis, Leen; Van den Broeck, Nick; Heng, Somony; Siv, Sovannaroth; Sluydts, Vincent; Sochantha, Tho; Coosemans, Marc; Durnez, Lies

2014-12-01

Scaling up of insecticide treated nets has contributed to a substantial malaria decline. However, some malaria vectors, and most arbovirus vectors, bite outdoors and in the early evening. Therefore, topically applied insect repellents may provide crucial additional protection against mosquito-borne pathogens. Among topical repellents, DEET is the most commonly used, followed by others such as picaridin. The protective efficacy of two formulated picaridin repellents against mosquito bites, including arbovirus and malaria vectors, was evaluated in a field study in Cambodia. Over a period of two years, human landing collections were performed on repellent treated persons, with rotation to account for the effect of collection place, time and individual collector. Based on a total of 4996 mosquitoes collected on negative control persons, the overall five hour protection rate was 97.4% [95%CI: 97.1-97.8%], not decreasing over time. Picaridin 20% performed equally well as DEET 20% and better than picaridin 10%. Repellents performed better against Mansonia and Culex spp. as compared to aedines and anophelines. A lower performance was observed against Aedes albopictus as compared to Aedes aegypti, and against Anopheles barbirostris as compared to several vector species. Parity rates were higher in vectors collected on repellent treated person as compared to control persons. As such, field evaluation shows that repellents can provide additional personal protection against early and outdoor biting malaria and arbovirus vectors, with excellent protection up to five hours after application. The heterogeneity in repellent sensitivity between mosquito genera and vector species could however impact the efficacy of repellents in public health programs. Considering its excellent performance and potential to protect against early and outdoor biting vectors, as well as its higher acceptability as compared to DEET, picaridin is an appropriate product to evaluate the epidemiological

Mosquito Bite Prevention For Travelers

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... bites. Here’s how: Keep mosquitoes out of your hotel room or lodging Š Choose a hotel or lodging with air conditioning or screens on ... percentages of active ingredient provide longer protection Some brand name examples* (Insect repellents may be sold under ...

Epidemiological study of insect bite reactions from Central India

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Sumit Kar

2013-01-01

Full Text Available Introduction: The physical effects of the arthropod bites on human skin receive less attention, especially in the rural areas where the per capita income is less. Ours is a rural-based hospital, the vicinity having more of plants, trees, and forests; we undertook the study to find out the relation of insect bite dermatitis in a rural area. Materials and Methods: The study was carried out in the Dermatology outpatient department of our institute on 100 subjects of insect bite dermatitis who were questioned retrospectively about the sequence of events besides their environmental and living conditions. They were examined thoroughly and the relevant clinical findings were noted, also taking into account the prior treatment taken by them, if any. Results and Conclusions: It was found that insect bite dermatitis has no age or gender preponderance, and the protective factors for the same are use of full sleeve clothes and keeping the doors and windows closed at night. On the contrary, the risk factors are residence in areas of heavy insect infestation, use of perfumes and colognes, warm weather in spring and summer and the lack of protective measures. However, there was no direct association of atopy with increased risk of developing insect bite dermatitis.

Ethnobotanical study of some of mosquito repellent plants in north-eastern Tanzania

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Tenu Filemoni

2008-08-01

Full Text Available Abstract Background The use of plant repellents against nuisance biting insects is common and its potential for malaria vector control requires evaluation in areas with different level of malaria endemicity. The essential oils of Ocimum suave and Ocimum kilimandscharicum were evaluated against malaria vectors in north-eastern Tanzania. Methodology An ethnobotanical study was conducted at Moshi in Kilimanjaro region north-eastern Tanzania, through interviews, to investigate the range of species of plants used as insect repellents. Also, bioassays were used to evaluate the protective potential of selected plants extracts against mosquitoes. Results The plant species mostly used as repellent at night are: fresh or smoke of the leaves of O. suave and O. kilimandscharicum (Lamiaceae, Azadirachta indica (Meliaceae, Eucalyptus globules (Myrtaceae and Lantana camara (Verbenaceae. The most popular repellents were O. kilimandscharicum (OK and O. suave (OS used by 67% out of 120 households interviewed. Bioassay of essential oils of the two Ocimum plants was compared with citronella and DEET to study the repellence and feeding inhibition of untreated and treated arms of volunteers. Using filter papers impregnated with Ocimum extracts, knockdown effects and mortality was investigated on malaria mosquito Anopheles arabiensis and Anopheles gambiae, including a nuisance mosquito, Culex quinquefasciatus. High biting protection (83% to 91% and feeding inhibition (71.2% to 92.5% was observed against three species of mosquitoes. Likewise the extracts of Ocimum plants induced KD90 of longer time in mosquitoes than citronella, a standard botanical repellent. Mortality induced by standard dosage of 30 mg/m2 on filter papers, scored after 24 hours was 47.3% for OK and 57% for OS, compared with 67.7% for citronella. Conclusion The use of whole plants and their products as insect repellents is common among village communities of north-eastern Tanzania and the results

Stinging and biting insect allergy: an Australian experience.

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Solley, Graham O

2004-12-01

Stings and bites from various insects are responsible for many anaphylactic events. To document the clinical features of specific forms of anaphylaxis and investigate clinical concerns regarding stinging and biting insect allergy. All patients presenting for evaluation of adverse reactions to insect stings or bites between December 1980 and December 1997 had the clinical details of their reactions recorded and their reactions classified. The spectrum of clinical symptoms and signs is similar to that seen in anaphylaxis from other sources; stings on the head or neck are not more likely to cause life-threatening reactions than stings elsewhere on the body; a lesser reaction will not necessarily lead to a more serious reaction from a future sting; asthmatic patients do appear to have an increased risk of asthma as a feature of their anaphylactic response; anaphylaxis is usually confined to a particular insect species for the individual patient; patients who have had multiple stings at one time may have experienced true anaphylaxis and not a "toxic" response; and patients who have had anaphylaxis from other sources are at no greater risk than that of the general population of reacting similarly to insect stings or bites. Anaphylactic events from insect stings show the same clinical features as those from other sources. Systemic reactions seem confined to a specific insect species. Patients who experience RXN3 reactions from multiple stings at one time should undergo specific venom testing, because many have experienced true anaphylaxis and not a toxic response. Future consideration should be given to the role of beta-adrenergic antagonists and ACE inhibitors in patients with systemic reactions.

Bug bites and stings: When to see a dermatologist

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Full Text Available ... and treatments Acne and rosacea Bumps and growths Color problems Contagious skin diseases Cosmetic treatments Dry / sweaty ... prevent bug bites, dermatologists recommend the following tips: Use insect repellent. To protect against mosquitoes, ticks and ...

Toxicity, repellency and flushing out in Triatoma infestans (Hemiptera: Reduviidae exposed to the repellents DEET and IR3535

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Mercedes M.N. Reynoso

2017-05-01

Full Text Available DEET and IR3535 are insect repellents present worldwide in commercial products; their efficacy has been mainly evaluated in mosquitoes. This study compares the toxicological effects and the behavioral responses induced by both repellents on the blood-sucking bug Triatoma infestans Klug (Hemiptera: Reduviidae, one of the main vectors of Chagas disease. When applied topically, the Median Lethal Dose (72 h for DEET was 220.8 µg/insect. Using IR3535, topical application of 500 µg/insect killed no nymphs. The minimum concentration that produced repellency was the same for both compounds: 1,15 µg/cm2. The effect of a mixture DEET:IR3535 1:1 was similar to that of their pure components. Flushing out was assessed in a chamber with a shelter containing groups of ten nymphs. The repellents were aerosolized on the shelter and the number of insects leaving it was recorded for 60 min. During that time, 0.006 g/m3 of the positive control tetramethrin flushed out 76.7% of the nymphs, while 1.76 g/m3 of DEET or IR3535 flushed out 30 and 0%, respectively. The concentrations required for both compounds to produce toxicity or flushing out are too high to have any practical applications. However, they showed a promising repellency. Additional research should be done to evaluate their possible use for personal protection against T. infestans bites.

[Study on essential oils of medicinal plants in insect repellent].

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Zhao, Hong-Zheng; Luo, Jiao-Yang; Liu, Qiu-Tao; Lv, Ze-Liang; Yang, Shi-Hai; Yang, Mei-Hua

2016-01-01

Mosquitoes are seriously harmful to human health for transmitting some mortal diseases. Among the methods of mosquito control, synthetical insecticides are the most popular. However, as a result of longterm use of these insecticides, high resistant mosquitos and heavy environmental pollution appear. Thus, eco-friendly prevention measures are taken into the agenda. Essential oils extracted from medicinal plants have repellent and smoked killing effects on mosquitoes. With abundant medical plants resources and low toxicity, they have the potential of being developed as a new type of mosquito and insect repellent agent. The recent application advances of essential oils of medicinal plants in insect repellent and its application limitations are overviewed. This review will provide references for the future development and in-depth study of essential oils. Copyright© by the Chinese Pharmaceutical Association.

Identification of the mosquito biting deterrent constituents from the Indian folk remedy plant Jatropha curcas

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An investigation of the Indian folk remedy plant, Jatropha curcas, was performed to specifically identify the constituents responsible for the mosquito biting deterrent activity of the oil as a whole. Jatropha curcas seed oil is burned in oil lamps in India and part of Africa to repel biting insect...

Insect Repellents and Associated Personal Protection for a Reduction in Human Disease

Science.gov (United States)

2012-01-01

of topical repellents and scrub typhus was reduced through the use of treated clothing. Successful reduction of leishmaniasis was achieved through the...epidemic typhus , scrub typhus , plague and malaria. The result was the development of many of the modern strategies for vector control that we take for...prevent bites and disease. They gave examples that represented well-documented disease reduction achieved with repellent clothing ( scrub typhus ; McCulloch

Genome-wide association study of insect bite hypersensitivity in two horse populations in the Netherlands

NARCIS (Netherlands)

Schurink, A.; Wolc, A.; Ducro, B.J.; Frankena, K.; Garrick, D.J.; Dekkers, J.C.M.; Arendonk, van J.A.M.

2012-01-01

Background: Insect bite hypersensitivity is a common allergic disease in horse populations worldwide. Insect bite hypersensitivity is affected by both environmental and genetic factors. However, little is known about genes contributing to the genetic variance associated with insect bite

Field evaluation of the efficacy of proprietary repellent formulations with IR3535 and picaridin against Aedes aegypti.

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Naucke, T J; Kröpke, R; Benner, G; Schulz, J; Wittern, K P; Rose, A; Kröckel, U; Grünewald, H W

2007-06-01

Seven proprietary repellent formulations (3 hydro-alcoholic spray solutions and 4 skin lotions) with active ingredient IR3,535 (ethyl butylacetylaminopropionate, EBAAP) or Picaridin (hydroxyethyl isobutyl piperidine carboxylate, KBR 3,023, Bayrepel) were tested in a field study on 10 test persons over a period of 10 h for their efficacy at preventing bites. The tests were conducted in Belo Horizonte, Brazil on field populations of the yellow fever mosquito Aedes aegypti. The concentration of the active substances ranged from 10% to 20%. All the tested samples provided lasting protection (time to first bite) over several hours: ranging from 5 h 20 min to 6 h 50 min with a mean of approximately 6 h. The longest protection until the second bite (=first confirmation bite) was approximately 7 h 40 min, whereas the shortest protection was 6 h 50 min. The longest protection until the third bite (=second confirmation bite) was 8 h 35 min, whereas the shortest protection was 7 h 40 min. In the control tests in which none of the samples were applied, the mean times until the first, second and third bites were 26, 46 and 59 min, respectively. The basis for this field study was provided by two American guidelines, which have the greatest international acceptance. The first is a draft guideline from the Environmental Protection Agency (EPA (United States Environmental Protection Agency), Product performance test guidelines. OPPTS 810.3700. Insect repellents for human skin and outdoor premises. Public Draft, 1999) and the second is a standard from the American Society for Testing and Materials (ASTM (American Society for Testing and Materials International), E 939-94 (reapproved 2,000): standard test method of field testing topical applications of compounds as repellents for medically important and pest arthropods (including insects, ticks, and mites): I. Mosquitoes, 2,000). Both guidelines recommend measuring the duration of protection until the first and second bites and also

Sustainable manufacture of insect repellents derived from Nepeta cataria.

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Patience, Gregory S; Karirekinyana, Ginette; Galli, Federico; Patience, Nicolas A; Kubwabo, Cariton; Collin, Guy; Bizimana, Jean Claude; Boffito, Daria C

2018-02-02

Malaria devastates sub-Saharan Africa; the World Health Organization (WHO) estimates that 212 million people contract malaria annually and that the plasmodium virus will kill 419 000 in 2017. The disease affects rural populations who have the least economic means to fight it. Impregnated mosquito nets have reduced the mortality rate but the Anopheles mosquitoes are changing their feeding patterns and have become more active at dusk and early morning rather than after 22h00 as an adaptation to the nets. Everyone is susceptible to the Anopheles at these times but infants and pregnant women are the most vulnerable to the disease. Plant-based mosquito repellents are as effective as synthetic repellents that protect people from bites. They are sustainable preventative measures against malaria not only because of their efficacy but because the local population can produce and distribute them, which represents a source of economic growth for rural areas. Here, we extract and test the essential oil nepetalactone from Nepeta cataria via steam distillation. Families in endemic areas of Burundi found them effective against bites but commented that the odor was pungent. An epidemiological study is required to establish its clinical efficacy.

Repellent Activity of TRIG (N-N Diethyl Benzamide against Man-Biting Mosquitoes

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Shandala Msangi

2018-01-01

Full Text Available A study was conducted to assess efficacy of a new repellent brand TRIG (15% N-N Diethyl Benzamide when compared to DEET (20% N-N Methyl Toluamide. The repellents were tested in laboratory and field. In the laboratory, the repellence was tested on human volunteers, by exposing their repellent-treated arms on starved mosquitoes in cages for 3 minutes at hourly intervals, while counting the landing and probing attempts. Anopheles gambiae and Aedes aegypti mosquitoes were used. Field evaluation was conducted by Human Landing Catch technique. During the night, the repellents were applied on arms and legs and mosquitoes landing on these areas were collected. In laboratory tests, TRIG provided complete protection (100% against Anopheles gambiae when applied at 1.25 g, while DEET provided this at 0.75 g. When tested on Aedes aegypti, TRIG provided complete protection when applied at 1 g, compared to 0.5 g for DEET. In the field, when applied at a recommended dose, both TRIG and DEET achieved above 90% protection against both An. arabiensis and Culex quinquefasciatus and a Complete Protection Time of about 6 hrs against both species of mosquitoes. The performances of the two products were found to be comparable and TRIG was recommended for use as repellent against mosquito bites.

Repellent Activity of TRIG (N-N Diethyl Benzamide) against Man-Biting Mosquitoes.

Science.gov (United States)

Msangi, Shandala; Kweka, Eliningaya; Mahande, Aneth

2018-01-01

A study was conducted to assess efficacy of a new repellent brand TRIG (15% N-N Diethyl Benzamide) when compared to DEET (20% N-N Methyl Toluamide). The repellents were tested in laboratory and field. In the laboratory, the repellence was tested on human volunteers, by exposing their repellent-treated arms on starved mosquitoes in cages for 3 minutes at hourly intervals, while counting the landing and probing attempts. Anopheles gambiae and Aedes aegypti mosquitoes were used. Field evaluation was conducted by Human Landing Catch technique. During the night, the repellents were applied on arms and legs and mosquitoes landing on these areas were collected. In laboratory tests, TRIG provided complete protection (100%) against Anopheles gambiae when applied at 1.25 g, while DEET provided this at 0.75 g. When tested on Aedes aegypti, TRIG provided complete protection when applied at 1 g, compared to 0.5 g for DEET. In the field, when applied at a recommended dose, both TRIG and DEET achieved above 90% protection against both An. arabiensis and Culex quinquefasciatus and a Complete Protection Time of about 6 hrs against both species of mosquitoes. The performances of the two products were found to be comparable and TRIG was recommended for use as repellent against mosquito bites.

Development of botanical-based biopesticides and repellents against biting flies on livestock animals

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Biting flies are important insect pests causing millions of dollars in losses to the livestock industry. The attack by biting flies causes significant losses in animal production and potential food contamination and disease transmission. This presentation reports our recent findings on the developme...

Evidence for inhibition of cholinesterases in insect and mammalian nervous systems by the insect repellent deet

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Dimitrov Mitko

2009-08-01

Full Text Available Abstract Background N,N-Diethyl-3-methylbenzamide (deet remains the gold standard for insect repellents. About 200 million people use it every year and over 8 billion doses have been applied over the past 50 years. Despite the widespread and increased interest in the use of deet in public health programmes, controversies remain concerning both the identification of its target sites at the olfactory system and its mechanism of toxicity in insects, mammals and humans. Here, we investigated the molecular target site for deet and the consequences of its interactions with carbamate insecticides on the cholinergic system. Results By using toxicological, biochemical and electrophysiological techniques, we show that deet is not simply a behaviour-modifying chemical but that it also inhibits cholinesterase activity, in both insect and mammalian neuronal preparations. Deet is commonly used in combination with insecticides and we show that deet has the capacity to strengthen the toxicity of carbamates, a class of insecticides known to block acetylcholinesterase. Conclusion These findings question the safety of deet, particularly in combination with other chemicals, and they highlight the importance of a multidisciplinary approach to the development of safer insect repellents for use in public health.

Insect Repellents: Modulators of Mosquito Odorant Receptor Activity

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2010-08-01

Laboratory, Henry A. Wallace Beltsville Agricultural Research Center, Plant Sciences Institute, Agricultural Research Service, United States Department...origin. 2-U is a naturally occurring compound produced by the glandular trichomes of wild tomato plants as part of a plant defense mechanism against...antennal OSNs responding to carboxylic acids and monoterpenes [23]. In our study, we investigate the action of 4 insect repellents on the activities of

Laboratory and field evaluation of the impact of exercise on the performance of regular and polymer-based deet repellents.

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Schofield, Steven; Tepper, Martin; Gadawski, Randy

2007-11-01

Studies were done in Manitoba, Canada, to evaluate the impact of exercise on repellent performance against mosquitoes. Two products containing the active ingredient N,N-diethyl-3-methylbenzamide (deet) were tested; one product was a polymer-based cream (3M Ultrathon Insect Repellent) and the other product was an alcohol-based pump spray formulation (Muskol Insect Repellent). Assessments were done in the laboratory using Aedes aegypti (L.) and in the field with naturally occurring populations of mosquitoes. Repellent was applied to the forearms (laboratory) or a lower leg (field) of test subjects at 1.5 g of test product per 600 cm2 surface area (0.75 or 0.83 mg deet/cm2). For a given test day, subjects exercised or did not. Exposure to mosquito attack was for 1 min at 30-min intervals in laboratory procedures, and it was continuous in field tests. Performance was measured as complete protection time (CPT). Moderate levels of physical activity resulted in a >40% decline in mean CPT, from 468 to 267 min in the laboratory experiments and from 359 to 203 min in field tests. Repellent product did not affect the magnitude of the decline. Mean biting pressure during field trials was 21.3 bites per min, and mosquito collections were made up primarily of Ochlerotatus sticticus (Meigen) and Aedes vexans (Meigen).

Use of repellents formulated in Specialized Pheromone and Lure Application Technology (SPLAT®) for effective insect pest management

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Agenor Mafra-Neto; Christopher J. Fettig; A. Steven Munson; Lukasz L. Stelinski

2014-01-01

Despite the many impediments to commercialization of insect repellents in agriculture and forestry, there are some situations where the use of repellents is desirable and warranted. ISCA Technologies (Riverside, California), together with collaborators from academic, government, and private sectors, is actively developing repellent formulations against several...

Gustatory receptor neuron responds to DEET and other insect repellents in the yellow-fever mosquito, Aedes aegypti

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Sanford, Jillian L.; Shields, Vonnie D. C.; Dickens, Joseph C.

2013-03-01

Three gustatory receptor neurons were characterized for contact chemoreceptive sensilla on the labella of female yellow-fever mosquitoes, Aedes aegypti. The neuron with the smallest amplitude spike responded to the feeding deterrent, quinine, as well as N, N-diethyl-3-methylbenzamide and other insect repellents. Two other neurons with differing spikes responded to salt (NaCl) and sucrose. This is the first report of a gustatory receptor neuron specific for insect repellents in mosquitoes and may provide a tool for screening chemicals to discover novel or improved feeding deterrents and repellents for use in the management of arthropod disease vectors.

Culicoides obsoletus extract relevant for diagnostics of insect bite hypersensitivity in horses

NARCIS (Netherlands)

Meide, van der N.M.A.; Meulenbroeks, C.; Altena, van S.E.C.; Schurink, A.; Ducro, B.J.; Wagner, B.; Leibold, W.; Rohwer, J.; Jacobs, F.; Sloet van Oldruitenborgh-Oosterbaan, M.M.; Savelkoul, H.F.J.; Tijhaar, E.

2012-01-01

Insect bite hypersensitivity (IBH) is an allergic dermatitis in horses caused by the bites of Culicoides species. The aim of the present study was to evaluate the applicability of whole body extracts of C. obsoletus (the main species found feeding on horses in the Netherlands), C. nubeculosus

Genome-wide association study of insect bite hypersensitivity in two horse populations in the Netherlands

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Schurink Anouk

2012-10-01

Full Text Available Abstract Background Insect bite hypersensitivity is a common allergic disease in horse populations worldwide. Insect bite hypersensitivity is affected by both environmental and genetic factors. However, little is known about genes contributing to the genetic variance associated with insect bite hypersensitivity. Therefore, the aim of our study was to identify and quantify genomic associations with insect bite hypersensitivity in Shetland pony mares and Icelandic horses in the Netherlands. Methods Data on 200 Shetland pony mares and 146 Icelandic horses were collected according to a matched case–control design. Cases and controls were matched on various factors (e.g. region, sire to minimize effects of population stratification. Breed-specific genome-wide association studies were performed using 70 k single nucleotide polymorphisms genotypes. Bayesian variable selection method Bayes-C with a threshold model implemented in GenSel software was applied. A 1 Mb non-overlapping window approach that accumulated contributions of adjacent single nucleotide polymorphisms was used to identify associated genomic regions. Results The percentage of variance explained by all single nucleotide polymorphisms was 13% in Shetland pony mares and 28% in Icelandic horses. The 20 non-overlapping windows explaining the largest percentages of genetic variance were found on nine chromosomes in Shetland pony mares and on 14 chromosomes in Icelandic horses. Overlap in identified associated genomic regions between breeds would suggest interesting candidate regions to follow-up on. Such regions common to both breeds (within 15 Mb were found on chromosomes 3, 7, 11, 20 and 23. Positional candidate genes within 2 Mb from the associated windows were identified on chromosome 20 in both breeds. Candidate genes are within the equine lymphocyte antigen class II region, which evokes an immune response by recognizing many foreign molecules. Conclusions The genome-wide association

A Pilot Qualitative Investigation of Stakeholders’ Experiences and Opinions of Equine Insect Bite Hypersensitivity in England

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Hannah R. Lomas

2018-01-01

Full Text Available Equine insect bite hypersensitivity (IBH, commonly known as sweet itch or summer eczema, is a frustrating recurrent skin disease in the equine industry involving an immune reaction to the bites of Culicoides spp. midges. To investigate the impact of IBH in the field, an exploratory pilot study was conducted with equine stakeholders in one region of central England. Nine semi-structured, face-to-face interviews were conducted with horse owners and an equine veterinarian. The aim was to gain an understanding of experiences with IBH, and to gauge opinions on the value of the various management strategies horse owners use to control IBH. Awareness of IBH was generally high, particularly in those individuals who had previous experience with the condition. Those with previous experience of IBH commented on the significant effect on daily routines, and the associated cost implications. Most participants supported an integrated approach to hypersensitivity management, and this most commonly involved a combination of physical barriers and chemical repellents, but sometimes included feed supplementation. Overall, attitudes towards IBH suggested that the condition is a notable welfare and economic concern for stakeholders, but veterinary involvement tended to only be in more severe cases. Further research is required in the future to improve understanding, management and potential treatment of this condition.

Genome-wide association study of insect bite hypersensitivity in swedish-born icelandic horses

NARCIS (Netherlands)

Shrestha, M.; Eriksson, S.; Schurink, A.; Andersson, L.S.; Sundquist, M.; Frey, R.; Brostrom, H.; Bergstrom, T.; Ducro, B.J.; lindgren, G.

2015-01-01

Insect bite hypersensitivity (IBH) is the most common allergic skin disease in horses and is caused by biting midges, mainly of the genus Culicoides. The disease predominantly comprises a type I hypersensitivity reaction, causing severe itching and discomfort that reduce the welfare and commercial

Repelentes de insetos: recomendações para uso em crianças Insect repellents: recommendations for use in children

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Germana Pimentel Stefani

2009-03-01

Full Text Available OBJETIVO: Apresentar uma revisão bibliográfica sobre o uso de repelentes de insetos em crianças, com ênfase especial na proteção contra mosquitos. FONTES DE DADOS: Realizou-se uma pesquisa bibliográfica nas bases de dados Pubmed e Lilacs, cujos artigos incluíam produtos comercialmente disponíveis no Brasil. Foram selecionados artigos publicados nos últimos dez anos em língua inglesa ou portuguesa, referentes a crianças, obtidos com as seguintes palavras-chave: "insect repellents", "children", "mosquitoes", "N,N-dietil-metatoluamida (DEET". SÍNTESE DOS DADOS: Entre os repelentes tópicos, DEET, icaridina e óleo natural de eucalipto-limão apresentam, em concentrações adequadas, perfil de segurança favorável e são eficazes na prevenção de picadas de mosquitos em crianças e adultos. Em geral, são indicados para crianças acima de dois anos de idade. Medidas físicas são fundamentais para proteger lactentes jovens, especialmente menores de seis meses, com destaque para o uso de telas com permetrina. CONCLUSÕES: Os mosquitos são vetores de doenças infectoparasitárias que acometem, anualmente, milhões de pessoas no mundo e causam milhares de mortes. O combate aos mosquitos inclui medidas ambientais e de proteção individual. O uso de repelentes tópicos para proteção individual da criança exige cuidados específicos e conhecimento quanto ao produto ideal para cada idade, especialmente quando consideradas sua eficácia e segurança.OBJECTIVE: To present a literature review about the use of insect repellents on children, highlighting the protection against mosquitoes. DATA SOURCES: Pubmed and Lilacs databases were searched for articles in English and Portuguese published in the last ten years with the following key-words: "insect repellents", "children", "mosquitoes", "N,N-dietil-metatoluamida (DEET". DATA SYNTHESIS: Concerning topical repellents, DEET, icaridine and natural oil of lemon eucalyptus are effective to

Insect bites and stings

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... widow spider bite; Brown recluse bite; Flea bite; Honey bee or hornet sting; Lice bites; Mite bite; ... Saunders; 2016:chap 359. Otten EJ. Venomous animal injuries. In: Walls RM, Hockberger RS, Gausche-Hill M, ...

The efficacy of repellents against Aedes, Anopheles, Culex and Ixodes spp. - a literature review.

Science.gov (United States)

Lupi, Eleonora; Hatz, Christoph; Schlagenhauf, Patricia

2013-01-01

Travellers are confronted with a variety of vector-borne threats. Is one type of repellent effective against all biting vectors? The aim of this review is to examine the literature, up to December 31st, 2012, regarding repellent efficacy. We searched PubMed for relevant papers. Repellents of interest were DEET, Icaridin as well as other piperidine-derived products (SS220), Insect Repellent (IR) 3535 (ethyl-butylacetyl-amino-propionat, EBAAP) and plant-derived products, including Citriodora (para-menthane-3,8-diol). As vectors, we considered the mosquito species Anopheles, Aedes and Culex as well as the tick species Ixodes. We selected only studies evaluating the protective efficacy of repellents on human skin. We reviewed a total of 102 publications. Repellents were evaluated regarding complete protection time or as percentage efficacy [%] in a time interval. We found no standardized study for tick bite prevention. Regarding Aedes, DEET at concentration of 20% or more, showed the best efficacy providing up to 10 h protection. Citriodora repellency against this mosquito genus was lower compared to the other products. Also between subspecies a difference could be observed: Ae. aegypti proved more difficult to repel than Ae. Albopictus. Fewer studies have been conducted on mosquito species Anopheles and Culex. The repellency profile against Anopheles species was similar for the four principal repellents of interest, providing on average 4-10 h of protection. Culex mosquitoes are easier to repel and all four repellents provided good protection. Few studies have been conducted on the tick species Ixodes. According to our results, the longest protection against Ixodes scapularis was provided by repellents containing IR3535, while DEET and commercial products containing Icaridin or PMD showed a better response than IR3535 against Ixodes ricinus. Many plant-based repellents provide only short duration protection. Adding vanillin 5% to plant-based repellents and to DEET

Are commercially available essential oils from Australian native plants repellent to mosquitoes?

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Maguranyi, Suzann K; Webb, Cameron E; Mansfield, Sarah; Russell, Richard C

2009-09-01

While the use of topical insect repellents, particularly those containing synthetic active ingredients such as deet (N,N-diethyl-3-methylbenzamide), are a mainstay in personal protection strategies emphasized in public health messages, there is a growing demand in the community for alternative repellents, particularly those of botanical origin and thus deemed to be "natural." This study evaluated the repellency of essential oils from 11 Australian native plants in 5% v/v formulations against Aedes aegypti, Culex quinquefasciatus, and Culex annulirostris under laboratory conditions. A blend of the top 3 performing oils was then compared with deet and a commercially available botanical insect repellent. All essential oils provided at least some protection against the 3 mosquito species, with the longest protection time (110 min) afforded by Prostanthera melissifolia against Cx. quinquefasciatus. Mean protection times against Ae. aegypti were substantially lower than those for the Culex spp. tested. Deet provided significantly longer protection against Ae. aegypti than both the 5% v/v blend of Leptospermum petersonii, Prostanthera melissifolia, and Melaleuca alternifolia (the 3 most effective oils) and the commercial botanical repellent. The results of this study indicate that these essential oils from Australian native plants offer limited protection against biting mosquitoes and that a blend of essential oils holds may offer commercial potential as a short-period repellent or under conditions of low mosquito abundance. However, it is important that public health messages continue to emphasize the greater effectiveness of deet-based repellents in areas with risks of mosquito-borne disease.

Mosquito density, biting rate and cage size effects on repellent tests.

Science.gov (United States)

Barnard, D R; Posey, K H; Smith, D; Schreck, C E

1998-01-01

Mosquito biting rates and the mean duration of protection (in hours) from bites (MDPB) of Aedes aegypti and Anopheles quadrimaculatus, using the repellent 'deet' (N,N-diethyl-3-methylbenzamide) on a 50 cm2 area of healthy human skin, were observed in small (27 l), medium (approximately 65 l) and large (125 l) cages containing low, medium or high densities of mosquitoes: respectively, 640, 128 or 49 cm3 of cage volume per female. At the initial treatment rate of approximately 0.4 microliter/cm2 (1 ml of 25% deet in ethanol on 650 cm2 of skin), the MDPB for deet against Ae. aegypti ranged from 4.5 to 6.5 h and was significantly less (5.0 +/- 0.8 h) in large cages compared with medium (6.2 +/- 0.9 h) and small (6.2 +/- 0.8 h) cages, regardless of the density. Against An. quadrimaculatus the MDPB for deet 0.4 microliter/cm2 was 1.5-8.0 h, less in small (3.7 +/- 2.3 h) and large (2.2 +/- 1.1 h) cages at medium (3.7 +/- 2.3 h) and high (2.5 +/- 1.7 h) mosquito densities, and was longest in medium cages (6.2 +/- 2.6 h) at low mosquito densities (5.8 +/- 2.8 h). With equinoxial photoperiodicity (light on 06.00-18.00 hours) the biting rate was influenced by the time of observation (08.00, 12.00, 16.00 hours) for Ae. aegypti but not for An. quadrimaculatus. For both species, the biting rate was inversely proportional to mosquito density and the MDPB. The shortest MDPBs were obtained in large cages with high densities of mosquitoes and longest protection times occurred in medium sized cages with low mosquito densities.

Evaluation of Repellency Effect of Essential Oils of Satureja khuzestanica (Carvacrol, Myrtus communis (Myrtle, Lavendula officinalis and Salvia sclarea using Standard WHO Repellency Tests.

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Mohammad Hassan Kayedi

2014-06-01

Full Text Available Using special lotions and repellent sprays on skin is one of the effective methods to prevent Arthropods biting which was verified in this study.Essential oils of four plants (Satureja khuzestanica, Salvia sclarea, Lavendula officinalis and Myrtus communis were separately extracted by Clevenger used hydro distillation method. Then separated solutions with 10%, 20% and 40% concentrations of essential oils of plants in 99.6 % ethanol were prepared. WHO guidelines for efficacy testing of mosquito repellents for human skin were used on different concentrations of essential oils of plants, traditional repellents (DEET, 50% and 33% as positive control, and ethanol 99.6% and naked hands as negative controls.In negative control groups, the number of bits were comparable (P= 0.42 and had decreasing time trends (naked hands P= 0.011, ethanol P< 0.001. In all time points, minimum bites were observed in traditional repellents and it was significantly less than the other groups (P< 0.001. The time trend in the number of bites in the other groups was positive and showed minimum number of bites in time zero in all groups. We also found that the concentration of repellents had association with the number of bites. The maximum and minimum numbers of bites were observed with 10% and 40% concentrations respectively in all groups.Essential oils of Salvia sclarea, Lavendula officinalis and Myrtus communis have repellency effect, even with 10% concentration of essential oils.

Comparative efficacy of IR3535 and deet as repellents against adult Aedes aegypti and Culex quinquefasciatus.

Science.gov (United States)

Cilek, J E; Petersen, J L; Hallmon, C E

2004-09-01

Arm-in-cage laboratory evaluations of 2 proprietary formulations of the mosquito repellents IR3535 and N,N-diethyl-3-methylbenzamide (deet; aqueous cream, hydroalcoholic spray) were made with 10 and 20% concentrations of each repellent. Also, 4 commercially available products containing IR3535 (Expedition insect repellent 20.07% active ingredient [AI], Bug Guard Plus with SPF30 sunscreen 7.5% AI, Bug Guard Plus with SPF15 sunscreen 7.5% AI, and Bug Guard Plus 7.5% AI) were tested. All comparisons were made on an equal formulation or concentration basis. Eight volunteers tested all formulations or products 3 times against laboratory-reared, Aedes aegypti and Culex quinquefasciatus mosquitoes (6-10 days old). Products were applied to a forearm at the rate of 0.002 g/cm2. The other forearm was not treated and served as a control. Elapsed time to 1st and 2nd consecutive bite was recorded. Mean protection time (i.e., time to 1st bite) with proprietary formulations of IR3535 were comparable to those of deet, with 20% concentrations providing greater protection against Ae. aegypti (3 h) and Cx. quinquefasciatus (6 h). Mean protection time for commercial products containing IR3535 ranged from nearly 90 to 170 min for Ae. aegypti and 3.5 to 6.5 h for Cx. quinquefasciatus. Mean time to the 2nd bite was similar to time to 1st bite for each mosquito species, product, and formulation.

Physicians, Primary Caregivers and Topical Repellent: All Under-Utilised Resources in Stopping Dengue Virus Transmission in Affected Households.

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Nguyet Minh Nguyen

2016-05-01

Full Text Available Primary health care facilities frequently manage dengue cases on an ambulatory basis for the duration of the patient's illness. There is a great opportunity for specific messaging, aimed to reduce dengue virus (DENV transmission in and around the home, to be directly targeted toward this high-risk ambulatory patient group, as part of an integrated approach to dengue management. The extent however, to which physicians understand, and can themselves effectively communicate strategies to stop focal DENV transmission around an ambulatory dengue case is unknown; the matter of patient comprehension and recollection then ensues. In addition, the effectiveness of N,N-diethyl-3-methylbenzamide (DEET-based insect repellent in protecting dengue patients from Aedes aegypti mosquitoes' bites has not been investigated.A knowledge, attitude and practice (KAP survey, focusing on the mechanisms of DENV transmission and prevention, was performed using semi-structured questionnaires. This survey was targeted towards the patients and family members providing supportive care, and physicians routinely involved in dengue patient management in Southern Vietnam. An additional clinical observational study was conducted to measure the efficacy of a widely-used 13% DEET-based insect repellent to repel Ae. aegypti mosquitoes from the forearms of dengue cases and matched healthy controls.Among both the physician (n = 50 and patient (n = 49 groups there were several respondents lacking a coherent understanding of DENV transmission, leading to some inappropriate attitudes and inadequate acute preventive practices in the household. The application of insect repellent to protect patients and their relatives from mosquito bites was frequently recommended by majority of physicians (78% participating in the survey. Nevertheless, our tested topical application of 13% DEET conferred only ~1hr median protection time from Ae. aegypti landing. This is notably shorter than that

Protection of Grain Products from Sitophilus oryzae (L.) Contamination by Anti-Insect Pest Repellent Sachet Containing Allyl Mercaptan Microcapsule.

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Chang, Yoonjee; Lee, Soo-Hyun; Na, Ja Hyun; Chang, Pahn-Shick; Han, Jaejoon

2017-11-01

The purpose of this study was to develop an anti-insect pest repellent sachet to prevent Sitophilus oryzae (L.) (Coleoptera: Curculionidae) contamination in grain packaging. The anti-insect pest activities of essential oils (EOs) from garlic (Allium Sativum), ginger (Zingiber Officinalis), black pepper (Piper nigrum), onion (Allium cepa), and fennel (Foeniculum vulgare) as well as major compounds (allyl disulfide, AD; allyl mercaptan, AM) isolated from of garlic and onion (AD and AM) were measured against S. oryzae. The results revealed that garlic EO, onion EO, AD, and AM showed strong fumigant insecticidal activities. Among these, AM showed the highest acetylcholinesterase (AChE) inhibition rate, indicating that the fumigation insecticidal efficacy of AM is related with its AChE inhibition ability. Subsequently, the microcapsules were produced with a high efficiency (80.02%) by using AM as a core material and rice flour as a wall material. Finally, sachet composed of rice flour microcapsule containing 2% AM (RAM) was produced. Repellent assay was performed to measure anti-insect pest ability of the RAM sachet, showed remarkable repelling effect within 48 h both in the presence or absence of attractant. In a release profile of RAM sachet, it was expected to last over 20 mo during the distribution period of brown rice. Moreover, RAM sachet showed no undesirable changes to the sensory properties of the rice both before and after cooking. Taken together, these results suggest that the newly developed RAM sachet could be used as a packaging material to protect grain products from S. oryzae contamination. The rice weevil, Sitophilus oryzae (L.) (Coleoptera: Curculionidae), causes damages to stored products and its contamination in grain products has become a major problem in cereal market. To preserve brown rice, an anti-insect pest repellent sachet containing 2% allyl mercaptan was newly developed and it showed remarkable repellent abilities against S. oryzae. It

Extract of the seeds of the plant Vitex agnus castus proven to be highly efficacious as a repellent against ticks, fleas, mosquitoes and biting flies.

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Mehlhorn, Heinz; Schmahl, Günter; Schmidt, Jürgen

2005-03-01

About 70 plant extracts were tested for their ability to repel the attacks of blood-sucking arthropods. It was found that a CO2 extract of the seeds of the Mediterranean plant Vitex agnus castus (monk's pepper) can be used as a spray to keep away especially Ixodes ricinus and Rhipicephalus sanguineus ticks from animals and humans for at least 6 h. In addition mosquitoes, biting flies and fleas are also repelled for about 6 h.

Mosquito repellent activity of piper guineense and xylopia ...

African Journals Online (AJOL)

The activity of eucalyptus oil (positive control), a commercial repellent, at 30% was only able to protect for 2h. Both oils used could be applied as repellents where protection from mosquito bite is sought for, over a short period of time. Keywords: Piper guineense, Xylopia aethiopica, volatile oils, Aedes aegypti, repellency

Synergistic insecticidal and repellent effects of combined pyrethroid and repellent-impregnated bed nets using a novel long-lasting polymer-coating multi-layer technique.

Science.gov (United States)

Faulde, Michael K; Nehring, Oliver

2012-08-01

New and improved strategies for malaria control and prevention are urgently needed. As a contribution to an optimized personal protection strategy, a novel long-lasting insecticide and repellent-treated net (LLIRN) has been designed by binding combinations of permethrin plus N,N-diethyl-m-toluamide (DEET), or insect repellent 3535 (IR3535), and etofenprox plus DEET, onto fibres of bed net fabric employing a new multi-layer polymer-coating technique. Protective repellent efficacy, toxicological effectiveness and residual activity of 12 LLIRN types have been evaluated by laboratory testing against adult Aedes aegypti. The novel multi-layer LLIRN design allowed simultaneous embedding at concentrations up to 5,930 mg/m(2) for DEET, 3,408 mg/m(2) for IR3535, 2,296 mg/m(2) for permethrin and 2,349 mg/m(2) for etofenprox, respectively. IR3535 layers prevented co-binding of additional pyrethroid-containing polymer layers, thus making pyrethroids plus DEET LLIRNs an ideal combination. All LLIRNs revealed synergistic insecticidal effects which, when measured against concentration controls of the isolated compounds, were significant in all LLIRN types designed. DEET in DEET plus permethrin LLIRNs significantly (p time from 55 to 75 %, the corresponding 100 % kill time (p time of etofenprox from 42 to 50 % (p = 0.004), the 100 % kill time from 25 to 38 % (p biting protection, even at low concentrations. One hundred percent biting and probing protection of stored LLIRNs was preserved for 83 weeks with the 5,930 mg/m(2) DEET and 2,139 mg/m(2) etofenprox LLIRN, for 72 weeks with the 5,002 mg/m(2) DEET and 2,349 mg/m(2) etofenprox LLIRN, for 63 weeks with the 3,590 mg/m(2) DEET and 1,208 mg/m(2) permethrin LLRN, and for 61 weeks with the 4,711 mg/m(2) DEET and 702 mg/m(2) etofenprox LLIRN. Because 100 % bite protection with up to 75 % quicker contact toxicity of pyrethroids were documented, synergistic toxicological and repellent effects of multi-layer polymer

Cloning and expression of candidate allergens from Culicoides obsoletus for diagnosis of insect bite hypersensitivity in horses

NARCIS (Netherlands)

Meide, van der N.M.A.; Roders, N.; Sloet van Oldruitenborgh-Oosterbaan, M.M.; Schaap, P.J.; Oers, van M.M.; Leibold, W.; Savelkoul, H.F.J.; Tijhaar, E.

2013-01-01

Insect bite hypersensitivity (IBH) is an IgE-mediated (Type I) hypersensitivity reaction induced by allergens from biting midges of the Culicoides spp. The aim of the present study was to identify, clone and express recombinant allergens from C. obsoletus, the main species found feeding on horses in

Non-biting flying insects as carriers of pathogenic bacteria in a Brazilian hospital

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Henrique Borges Kappel

2013-04-01

Full Text Available Introduction Insects have been described as mechanical vectors of nosocomial infections. Methods Non-biting flying insects were collected inside a pediatric ward and neonatal-intensive care unit (ICU of a Brazilian tertiary hospital. Results Most (86.4% of them were found to carry one or more species of bacteria on their external surfaces. The bacteria isolated were Gram-positive bacilli (68.2% or cocci (40.9%, and Gram-negative bacilli (18.2%. Conclusions Insects collected inside a hospital were carrying pathogenic bacteria; therefore, one must consider the possibility they may act as mechanical vectors of infections, in especially for debilitated or immune-compromised patients in the hospital environments where the insects were collected.

Plant insecticide L-canavanine repels Drosophila via the insect orphan GPCR DmX.

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Christian Mitri

2009-06-01

Full Text Available For all animals, the taste sense is crucial to detect and avoid ingesting toxic molecules. Many toxins are synthesized by plants as a defense mechanism against insect predation. One example of such a natural toxic molecule is L-canavanine, a nonprotein amino acid found in the seeds of many legumes. Whether and how insects are informed that some plants contain L-canavanine remains to be elucidated. In insects, the taste sense relies on gustatory receptors forming the gustatory receptor (Gr family. Gr proteins display highly divergent sequences, suggesting that they could cover the entire range of tastants. However, one cannot exclude the possibility of evolutionarily independent taste receptors. Here, we show that L-canavanine is not only toxic, but is also a repellent for Drosophila. Using a pharmacogenetic approach, we find that flies sense food containing this poison by the DmX receptor. DmXR is an insect orphan G-protein-coupled receptor that has partially diverged in its ligand binding pocket from the metabotropic glutamate receptor family. Blockade of DmXR function with an antagonist lowers the repulsive effect of L-canavanine. In addition, disruption of the DmXR encoding gene, called mangetout (mtt, suppresses the L-canavanine repellent effect. To avoid the ingestion of L-canavanine, DmXR expression is required in bitter-sensitive gustatory receptor neurons, where it triggers the premature retraction of the proboscis, thus leading to the end of food searching. These findings show that the DmX receptor, which does not belong to the Gr family, fulfills a gustatory function necessary to avoid eating a natural toxin.

Recombinant culicoides obsoletus complex allergens stimulate antigen-specific T cells on insect bite hypersensitive Shetland ponies in vitro

NARCIS (Netherlands)

Meulenbroeks, C.; Meide, van der N.M.A.; Willemse, T.; Rutten, V.; Tijhaar, E.J.

2015-01-01

Background Ponies may suffer from Insect bite hypersensitivity (IBH), an allergic IgE-mediated pruritic skin disorder, induced by allergens from biting midges of the Culicoides spp. Hypothesis/Objectives To determine whether recombinant Culicoides obsoletus allergens are able to activate T cells of

Celery-based topical repellents as a potential natural alternative for personal protection against mosquitoes.

Science.gov (United States)

Tuetun, B; Choochote, W; Pongpaibul, Y; Junkum, A; Kanjanapothi, D; Chaithong, U; Jitpakdi, A; Riyong, D; Pitasawat, B

2008-12-01

Celery-based products were investigated for chemical composition, skin irritation, and mosquito repellency in comparison to commercial repellents and the standard chemical, N,N-diethyl-3-methylbenzamide (DEET), with a goal to develop a natural alternative to synthetic repellents for protection against mosquitoes. Chemical identification by gas chromatography coupled with mass spectrometry discovered that the major constituents of Apium graveolens hexane extract (AHE) were 3-n-butyl-tetrahydrophthalide (92.48%), followed by 5.10% beta-selinene and 0.68% gamma-selinene. Evaluation of skin irritation in 27 human volunteers revealed no irritant potential from 25% ethanolic AHE solution. Laboratory investigated repellent against female Aedes aegypti mosquitoes demonstrated that G10 formula, the best AHE-developed product, provided remarkable repellency with a median protection time of 4.5 h (4.5-5 h), which was greater than that of ethanolic DEET solution (25% DEET, 3.5 h) and comparable to that of the best commercial repellent, Insect Block 28 (28.5% DEET, 4.5 h). According to significantly promising results, including highly effective repellency and no potential skin irritation or other side effects, the G10 formula is a worthwhile product that has the promise of being developed for commercialized registration. This developed AHE product could be an acceptable and affordable alternative to conventional synthetic chemicals in preventing mosquito bites, and in turn, helping to interrupt mosquito-borne disease transmission.

Altered behavioral responses of Sindbis virus-infected Aedes aegypti (Diptera: Culicidae) to DEET and non-DEET based insect repellents.

Science.gov (United States)

Qualls, Whitney A; Day, Jonathan F; Xue, Rui-de; Bowers, Doria F

2012-06-01

Changes in the time to first bite (TFB) and the bloodfeeding behavior of adult female Aedes aegypti (L.) mosquitoes following dissemination of Sindbis virus (SINV) were observed after exposure to repellents with the active ingredients (AI) DEET, picaridin, 2-undecanone (2-U), and oil of lemon eucalyptus. Dissemination of SINV significantly decreased (Ptimes were observed in SINV infected mosquitoes after exposure to the four repellents compared to uninfected mosquitoes. Taken together, a decrease in TFB and time to complete the four bloodfeeding stages will lessen the prey-status, and enhance both the chances of mosquito survival and arbovirus transmission. Published by Elsevier B.V.

POSSIBILITIES TO USE NATURAL EXTRACTS FROM MEDICINAL AND AROMATIC PLANTS (MAP LIKE BOTANICAL REPELLENT OR INSECTICIDE COMPOUNDS AGAINST PEST INSECTS IN ECOLOGICAL CROPS (II

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Irina IONESCU-MĂLĂNCUŞ

2013-12-01

Full Text Available Botanical insecticides have long been touted as attractive alternatives to synthetic chemical insecticides for pest management because botanicals reputedly pose little threat to the environment or to human health. The body of scientific literature documenting bioactivity of plant derivatives to arthropods pests continues to expand i.e. repellents based on essential oils extracted from Chenopodium ambrosioides, Eucalyptus saligna, Rosmarinus officinalis to mosquitoes, or cinnamon oil, sandalwood oil and turmeric oil are previously reported as insect repellents evaluatede in the laboratory conditions. With the constantly increasing problems of insecticide resistance and increasing public concerns regarding pesticide safety, new, safer active ingredients are becoming necessary to replace existing compounds on the market. The present study carried out in the period 2010-2012 comprises a review of two insect repellents, followed by some new research conducted in our laboratory on plant-derived insect repellents. The two alkaloids tested against the Colorado potato beetle, Leptinotarsa decemlineata Say in laboratory conditions was obtained by water and alchohol extraction from two vegetal species, Cichorium intybus L. (Asterales:Asteraceae and Delphinium consolida L. (Ranales:Ranunculaceae. The tests carried out in laboratory and field experimentally plots under cages permit to evaluate several other compounds for repellent activity of lacctucin alkaloids.

Repellent and deterrent effects of SS220, Picaridin, and Deet suppress human blood feeding by Aedes aegypti, Anopheles stephensi, and Phlebotomus papatasi.

Science.gov (United States)

Klun, Jerome A; Khrimian, Ashot; Debboun, Mustapha

2006-01-01

A series of behavioral tests with Aedes aegypti (L.), Anopheles stephensi Liston, mosquitoes, and the sand fly Phlebotomus papatasi Scopoli in the presence of Deet, SS220, and Picaridin topically applied to the skin of human volunteers showed that the insects were deterred from feeding on and repelled from surfaces emanating the compounds. When offered a 12- or 24-cm2 area of skin, one-half treated with compound and one-half untreated, the insects fed almost exclusively on untreated skin. The sand flies and mosquitoes did not at any time physically contact chemically treated surfaces. When treated and untreated skin areas were covered with cloth, insects contacted, landed, and bit only through cloth covering untreated skin. These observations provided evidence that the compounds deterred feeding and repelled insects from treated surfaces primarily as a result of olfactory sensing. When cloth, one-half untreated and one-half treated with chemical, was placed over untreated skin, insects only touched and specifically bit through the untreated cloth. This showed that the activity of the chemicals does not involve a chemical x skin interaction. In the presence of any of the three chemicals, no matter how they were presented to the insects, overall population biting activity was reduced by about one-half relative to controls. This reduction showed a true repellent effect for the compounds. Results clearly showed that Deet, SS220, and Picaridin exert repellent and deterrent effects upon the behavior of mosquitoes and sand flies. Heretofore, the combined behavioral effects of these compounds upon mosquito and sand fly behavior were unknown. Moreover, protection afforded by Deet, SS220, and Picaridin against the feeding of these three disease vectors on humans is mechanistically a consequence of the two chemical effects.

Protective efficacy of menthol propylene glycol carbonate compared to N, N-diethyl-methylbenzamide against mosquito bites in Northern Tanzania

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Kweka Eliningaya J

2012-09-01

Full Text Available Abstract Background The reduction of malaria parasite transmission by preventing human-vector contact is critical in lowering disease transmission and its outcomes. This underscores the need for effective and long lasting arthropod/insect repellents. Despite the reduction in malaria transmission and outcomes in Tanzania, personal protection against mosquito bites is still not well investigated. This study sought to determine the efficacy of menthol propylene glycol carbonate (MR08, Ocimum suave as compared to the gold standard repellent N, N-diethyl-methylbenzamide (DEET, either as a single dose or in combination (blend, both in the laboratory and in the field against Anopheles gambiae s.l and Culex quinquefasciatus. Methods In the laboratory evaluations, repellents were applied on one arm while the other arm of the same individual was treated with a base cream. Each arm was separately exposed in cages with unfed female mosquitoes. Repellents were evaluated either as a single dose or as a blend. Efficacy of each repellent was determined by the number of mosquitoes that landed and fed on treated arms as compared to the control or among them. In the field, evaluations were performed by human landing catches at hourly intervals from 18:00 hr to 01:00 hr. Results A total of 2,442 mosquitoes were collected during field evaluations, of which 2,376 (97.30% were An. gambiae s.l while 66 (2.70% were Cx. quinquefaciatus. MR08 and DEET had comparatively similar protective efficacy ranging from 92% to 100 for both single compound and blends. These findings indicate that MR08 has a similar protective efficacy as DEET for personal protection outside bed nets when used singly and in blends. Because of the personal protection provided by MR08, DEET and blends as topical applicants in laboratory and field situations, these findings suggest that, these repellents could be used efficiently in the community to complement existing tools. Overall, Cx

A novel test cage with an air ventilation system as an alternative to conventional cages for the efficacy testing of mosquito repellents.

Science.gov (United States)

Obermayr, U; Rose, A; Geier, M

2010-11-01

We have developed a novel test cage and improved method for the evaluation of mosquito repellents. The method is compatible with the United States Environmental Protection Agency, 2000 draft OPPTS 810.3700 Product Performance Test Guidelines for Testing of Insect Repellents. The Biogents cages (BG-cages) require fewer test mosquitoes than conventional cages and are more comfortable for the human volunteers. The novel cage allows a section of treated forearm from a volunteer to be exposed to mosquito probing through a window. This design minimizes residual contamination of cage surfaces with repellent. In addition, an air ventilation system supplies conditioned air to the cages after each single test, to flush out and prevent any accumulation of test substances. During biting activity tests, the untreated skin surface does not receive bites because of a screen placed 150 mm above the skin. Compared with the OPPTS 810.3700 method, the BG-cage is smaller (27 liters, compared with 56 liters) and contains 30 rather than hundreds of blood-hungry female mosquitoes. We compared the performance of a proprietary repellent formulation containing 20% KBR3023 with four volunteers on Aedes aegypti (L.) (Diptera: Culicidae) in BG- and conventional cages. Repellent protection time was shorter in tests conducted with conventional cages. The average 95% protection time was 4.5 +/- 0.4 h in conventional cages and 7.5 +/- 0.6 h in the novel BG-cages. The protection times measured in BG-cages were more similar to the protection times determined with these repellents in field tests.

Gustatory receptor neuron responds to DEET and other insect repellents in the yellow fever mosquito, aedes aegypti

Science.gov (United States)

Three gustatory receptor neurons were characterized for contact chemoreceptive sensilla on the labella of female yellow fever mosquitoes, Aedes aegypti. The neuron with the smallest amplitude spike responded to the feeding deterrent, quinine, as well as DEET and other insect repellents. Two other ...

Insects and Scorpions

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... insects or scorpions can be hazardous to outdoor workers. Stinging or biting insects include bees, wasps, hornets, and fire ants. The health effects of stinging or biting insects or scorpions range ...

Bug bites and stings: When to see a dermatologist

Medline Plus

Full Text Available ... that contains insect repellent, as sunscreen must be applied liberally and often while insect repellant should be applied sparingly. Wear appropriate clothing. If you know you’ ...

Composition and repellency of the essential oils of Evodia calcicola Chun ex Huang and Evodia trichotoma (Lour.) Pierre against three stored product insects.

Science.gov (United States)

Yang, Kai; You, Chun-Xue; Wang, Cheng-Fang; Guo, Shan-Shan; Li, Yin-Ping; Wu, Yan; Geng, Zhu-Feng; Deng, Zhi-Wei; Du, Shu-Shan

2014-01-01

During our screening program for agrochemicals from Chinese medicinal herbs and wild plants, the essential oils of Evodia calcicola and Evodia trichotoma leaves were found to possess strong repellency against the red flour beetle Tribolium castaneum adults, the cigarette beetle Lasioderma serricorne adults and the booklouse Liposcelis bostrychophila. The two essential oils obtained by hydrodistillation were investigated by GC-MS. The main components of E. calcicola essential oil were identified to be (-)-β-pinene (44.02%), β-phellandrene (20.93%), ocimene (16.49%), and D-limonene (9.87%). While the main components of the essential oil of E. trichotoma were D-limonene (69.55%), 1R-a-pinene (11.48%), caryophyllene (2.80%) and spathulenol (2.24%). Data showed that T. castaneum was the most sensitive than other two stored product insects. Compared with the positive control, DEET (N, N-diethyl-3- methylbenzamide), the two essential oils showed the same level repellency against the red flour beetle. However, the essential oil of E. trichotoma showed the same level repellency against the cigarette beetle, while E. calcicola essential oil possessed the less level repellency against L. serricorne, relative to the positive control, DEET. Moreover, the two crude oils also exhibited strong repellency against L. bostrychophila, but lesser level repellency than the positive control, DEET. Thus, the essential oils of E. calcicola and E. trichotoma may be potential to be developed as a new natural repellent in the control of stored product insects.

Anterior open bite treatment with magnets.

Science.gov (United States)

Kiliaridis, S; Egermark, I; Thilander, B

1990-11-01

The aim of this study was to examine the effects of repelling magnets on the treatment of anterior open bite and compare them with the effects of acrylic posterior bite-blocks. Twenty patients, aged 9-16 years with skeletal anterior open bite, were randomly divided into two groups. In one group the patients wore posterior repelling magnet splints and in the other they wore acrylic posterior bite-blocks of the same thickness as the magnet splints. The patients were instructed to use their appliance as much as possible (the minimum accepted being 18 hours daily) during a 6-month period. Dental casts, intra-oral photos, and lateral cephalograms were taken before and after treatment, and the patients were also examined regularly to identify the development of any craniomandibular disorders. In the first group, the dental and skeletal vertical relation responded quickly to the magnet treatment. The open bite was generally closed in just under 4 months, especially in patients in early mixed dentition. Spacing in the labial segments decreased in some cases, while slight crowding was induced in others. Transverse problems, i.e. unilateral cross-bite, sometimes followed by scissor-bite on the opposite side, was observed in those patients who were in the early mixed dentition and had used the magnets intensively. The patients who wore acrylic posterior bite-blocks also showed improvement in the dental and skeletal vertical relationships, especially during the first months. This was followed by a 'plateau' period. No transverse problems were found in these patients.

Investigating the repellency of trifluoromethylphenyl amides analogues against Aedes aegypti

Science.gov (United States)

The purpose of this study is to develop new repellents and evaluate their efficacy for personal protection against mosquitoes. The minimum effective dosage (MED) was determined to estimate the lowest passing concentration of a repellent that prevents >99% of mosquito bites through a treated cloth. D...

Polymeric nanoencapsulation of insect repellent: Evaluation of its bioefficacy on Culex quinquefasciatus mosquito population and effective impregnation onto cotton fabrics for insect repellent clothing

Directory of Open Access Journals (Sweden)

A.P.B. Balaji

2017-10-01

Full Text Available Diethylphenylacetamide (Bulk-DEPA, an organic insect repellent was subjected to Poly(ethylene glycol (PEG polymerization followed by Phase Inversion Temperature (PIT emulsification method to yield the polymeric nanodroplets of DEPA (Nano-DEPA. The mean hydrodynamic diameter was found to be 149 ± 1.06 nm. The efficacy of Bulk-DEPA and Nano-DEPA was comparatively investigated on the Culex quinquefasciatus mosquito population. The larvicidal bioassay was performed on the 1st, 2nd, and 3rd instar larvae of Culex quinquefasciatus and the median lethal indices (LC50 of was found to be 0.055, 0.208, 1.397 mg/L and 0.023, 0.144, 0.260 mg/L for Bulk-DEPA and Nano-DEPA respectively. The histopathological studies were found to be corroborative with the larvicidal bioassay. The median knockdown indices (KD50 on 2–3 day old sucrose fed adult mosquitoes determined by WHO cone bioassay and was found to be 55.168 and 33.277 mg/L for Bulk-DEPA and Nano-DEPA. The obtained results indicate the improved efficacy possessed by the Nano-DEPA as comparative to Bulk-DEPA even at lower concentrations. Further, the Nano-DEPA was impregnated onto the alginate cross-linked (ACL and Plain (PL cotton fabrics, and the Washing resistance index (WRI was determined. The obtained results indicate the higher WRI possessed by the ACL cotton fabric than the PL cotton fabric. This was owing to the effective physical entrapment of Nano-DEPA onto the alginate matrices, which was further substantiated by high-resolution scanning electron microscopic (HR-SEM studies. Overall, the present study has emphasized the benefit of formulating Bulk-DEPA into Nano-DEPA to exert higher efficacy on the mosquito population. In addition, study has provided the methodology for the effective impregnation of Nano-DEPA onto the cotton fabrics for the reliable application in long lasting insect repellent clothing.

Nootkatone is a repellent for Formosan subterranean termite (Coptotermes formosanus).

Science.gov (United States)

Zhu, B C; Henderson, G; Chen, F; Maistrello, L; Laine, R A

2001-03-01

We examined the behavior of Formosan subterranean termites toward one of the components of vetiver grass oil, the roots of which manufacture insect repellents. We found nootkatone, a sesquiterpene ketone, isolated from vetiver oil is a strong repellent and toxicant to Formosan subterranean termites. The lowest effective concentration tested was 10 micrograms/g substrate. This is the first report of nootkatone being a repellent to insects.

Bug bites and stings: When to see a dermatologist

Medline Plus

Full Text Available ... Rotation PICMED Grant Professionalism Award Resident-Fellow QI Project Award Resident International Grant Resident Scholarship to Legislative ... sunscreen that contains insect repellent, as sunscreen must be applied liberally and often while insect repellant should ...

Identification of factors associated with the development of insect bite hypersensitivity in horses in the Netherlands

NARCIS (Netherlands)

Boom, van den R.; Ducro, B.J.; Sloet van Oldruitenborgh-Oosterbaan, M.M.

2008-01-01

An Internet-based questionnaire among horse owners was carried out to identify factors affecting the incidence of insect bite hypersensitivity (IBHI) among horses in the Netherlands. Information was obtained for 794 horses of various breeds, but the breed distribution was not representative for the

Development of Natural Insect-Repellent Loaded Halloysite Nanotubes and their Application to Food Packaging to Prevent Plodia interpunctella Infestation.

Science.gov (United States)

Kim, Jungheon; Park, No-Hyung; Na, Ja Hyun; Han, Jaejoon

2016-08-01

The aims of this study were to develop insect-proof halloysite nanotubes (HNTs) and apply the HNTs to a low-density polyethylene (LDPE) film that will prevent Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae), commonly known as Indian mealmoth, from infesting the food. Clove bud oil (CO), an insect repellent, was encapsulated into HNTs with polyethylenimine (PEI) to bring about controlled release of CO. Chemical composition and insecticidal effect of CO were examined. The Fourier transform infrared (FTIR) spectrum of encapsulated CO was confirmed. The surface charges of uncoated HNTs (HNTs/CO) and coated HNTs with PEI by the layer-by-layer (LBL) method (HNTs/CO/LBL) were determined to be -37.23 and 36.33 mV, respectively. HNTs/CO/LBL showed slow, controlled release of CO compared to HNTs/CO. After 30 d, the residual amounts of CO in HNTs/CO and HNTs/CO/LBL were estimated to be 13.43 and 28.66 mg/g, respectively. HNTs/CO/LBL showed the most sustainable repellent effect. HNTs applied to gravure printing ink solution did not affect mechanical, optical, or thermal properties of the developed film. Gravure-printed LDPE film containing HNTs/CO/LBL displayed the greatest preventive effect on insect penetration, indicating its potential for use as insect-resistant food packaging materials. © 2016 Institute of Food Technologists®

Angelica sinensis (Umbelliferae) with proven repellent properties against Aedes aegypti, the primary dengue fever vector in Thailand.

Science.gov (United States)

Champakaew, D; Junkum, A; Chaithong, U; Jitpakdi, A; Riyong, D; Sanghong, R; Intirach, J; Muangmoon, R; Chansang, A; Tuetun, B; Pitasawat, B

2015-06-01

Botanical resources with great diversity in medicinal and aromatic plants are a rich and reliable source for finding insect repellents of plant origin, which are widely popular among today's consumers. Although some herbal-based repellents have been proven comparable to or even better than synthetics, commercially available natural repellents generally tend to be expensive, with short-lived effectiveness. This critical flaw leads to ongoing research for new and effective repellents, which provide longer protection against vector and nuisance-biting insects, while remaining safe, user friendly, and reasonably priced. This study aimed to evaluate the repellent activity of plant-derived products against the primary dengue vector, Aedes aegypti, by following the human bait technique of World Health Organization guidelines. Preliminary laboratory screening tests for repellency of 33 plant species clearly demonstrated Angelica sinensis as the most effective repellent from each kind of extracted product, with its essential oil and ethanolic extract having median complete protection times of 7.0 h (6.0-7.5) and 2.5 h (2.0-2.5), respectively. Due to its low yield (0.02 %), pungent smell, and little cause of irritation, A. sinensis essential oil did not qualify as a candidate for further repellent assessment. However, subsequent extractions of A. sinensis with different organic solvents of increasing polarity provided four extractants with varying degrees of repellency against A. aegypti. The hexane extract of A. sinensis provided excellent repellency, with a median complete protection time of 7.5 h (6.5-8.5), which was longer than that of ethanol (2.5, 2.0-2.5 h), acetone (1.75, 0.5-2.5 h), and methanol extracts (0.5, 0-1.0 h). By being the most effective product, A. sinensis hexane extract gave significant protection comparable to that of its essential oil and the standard synthetic repellent, N,N-diethyl-3-methylbenzamide (DEET: 6.25, 5.0-6.5 h). Qualitative gas

Insects and Bugs

Science.gov (United States)

Sutherland, Karen

2009-01-01

They have been around for centuries. They sting, they bite. They cause intense itching or painful sores. They even cause allergic reactions and sometimes death. There are two types of insects that are pests to humans--those that sting and those that bite. The insects that bite do so with their mouths and include mosquitoes, chiggers, and ticks.…

Repellent Activity of TRIG (N-N Diethyl Benzamide) against Man-Biting Mosquitoes

OpenAIRE

Msangi, Shandala; Kweka, Eliningaya; Mahande, Aneth

2018-01-01

A study was conducted to assess efficacy of a new repellent brand TRIG (15% N-N Diethyl Benzamide) when compared to DEET (20% N-N Methyl Toluamide). The repellents were tested in laboratory and field. In the laboratory, the repellence was tested on human volunteers, by exposing their repellent-treated arms on starved mosquitoes in cages for 3 minutes at hourly intervals, while counting the landing and probing attempts. Anopheles gambiae and Aedes aegypti mosquitoes were used. Field evaluation...

Avaliação do uso de repelentes contra picada de mosquitos em militares na Bacia Amazônica Evaluation of the use of repellent against mosquito bite by military personnel in the Amazon Basin

Directory of Open Access Journals (Sweden)

Jonas Ribas

2010-02-01

Full Text Available FUNDAMENTOS: No Brasil, doenças provocadas por picadas de insetos são frequentes, o que torna extremamente importante a execução de medidas profiláticas de forma adequada, sobretudo, em áreas endêmicas como a Amazônia, que recebe um grande contingente de visitantes, a trabalho ou turismo. OBJETIVOS: Avaliar o uso dos repelentes de insetos disponíveis no mercado por militares que costumam realizar missões em ambiente de selva, na região amazônica. MÉTODOS: Foram selecionados cinquenta e um militares da região amazônica que responderam um questionário em junho/2008. RESULTADOS: 63,7% dos militares usaram produtos contendo Deet na concentração máxima de apenas 15%, que possui mínima ação de repelência; 36% relataram usar protetor solar associado, o que levou a um risco maior de intoxicação; 36,4% fizeram uso de um repelente natural em suas missões; dois militares usaram vitamina B e consideraram a sua ação de repelência ineficaz. CONCLUSÕES: Os repelentes à base de Deet utilizados pelo grupo estudado apresentam concentrações inferiores às consideradas seguras para uso em ambiente de selva. Foi frequente a associação do Deet com protetor solar, que é uma combinação potencialmente tóxica. Os repelentes naturais à base de andiroba e copaíba apresentaram o maior grau de percepção de proteção.BACKGROUND: In Brazil, diseases caused by insect bites are frequent. Therefore, it is extremely important that prophylatic measures are adequately carried out, especially in endemic areas such as the Amazon which receives a great number of visitors, for both business and tourism purposes.. OBJECTIVES: To evaluate the use of insect repellents available in the market by military personnel who often go in missions in the middle of the jungle, in the Amazon region. METHODOLOGY: Fifty - one militaries in the Amazon region were selected and they answered a questionnaire in June/2008. RESULTS: 63,7% of the militaries used

Toxicity of a plant based mosquito repellent/killer

Science.gov (United States)

Singh, Prakash Raj; Mohanty, Manoj Kumar

2012-01-01

The mission to make humans less attractive to mosquitoes has fuelled decades of scientific research on mosquito behaviour and control. The search for the perfect topical insect repellent/killer continues. This analysis was conducted to review and explore the scientific information on toxicity produced by the ingredients/contents of a herbal product. In this process of systemic review the following methodology was applied. By doing a MEDLINE search with key words of selected plants, plant based insect repellents/killers pertinent articles published in journals and authentic books were reviewed. The World Wide Web and the Extension Toxicity Network database (IPCS-ITOX) were also searched for toxicology data and other pertinent information. Repellents do not all share a single mode of action and surprisingly little is known about how repellents act on their target insects. Moreover, different mosquito species may react differently to the same repellent. After analysis of available data and information on the ingredient, of the product in relation to medicinal uses, acute and chronic toxicity of the selected medicinal plants, it can be concluded that the ingredients included in the herbal product can be used as active agents against mosquitoes. If the product which contains the powder of the above said plants is applied with care and safety, it is suitable fo use as a mosquito repellent/killer. PMID:23554562

Contact and Repellent Activities of the Essential Oil from Juniperus formosana against Two Stored Product Insects

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Shanshan Guo

2016-04-01

Full Text Available The chemical composition of the essential oil from Juniperus formosana leaves and its contact and repellent activities against Tribolium castaneum and Liposcelis bostrychophila adults were investigated. The essential oil of J. formosana leaves was obtained by hydrodistillation and analyzed by GC-MS. A total of 28 components were identified and the main compounds in the essential oil were α-pinene (21.66%, 4-terpineol (11.25%, limonene (11.00% and β-phellandrene (6.63%. The constituents α-pinene, 4-terpineol and d-limonene were isolated from the essential oil. It was found that the essential oil exhibited contact activity against T. castaneum and L. bostrychophila adults (LD50 = 29.14 μg/adult and 81.50 µg/cm2, respectively. The compound 4-terpineol exhibited the strongest contact activity (LD50 = 7.65 μg/adult. In addition, data showed that at 78.63 nL/cm2, the essential oil and the three isolated compounds strongly repelled T. castaneum adults. The compounds α-pinene and d-limonene reached the same level (Class V of repellency as DEET (p = 0.396 and 0.664 against L. bostrychophila at 63.17 nL/cm2 after 2 h treatment. The results indicate that the essential oil and the isolated compounds have potential to be developed into natural insecticides and repellents to control insects in stored products.

Mediation of deet repellency in mosquitoes (Diptera: Culicidae) by species, age, and parity.

Science.gov (United States)

Barnard, D R

1998-05-01

Laboratory bioassays assessed differences in the protection time provided by the repellent deet (N,N-diethyl-3-methylbenzamide) against 5-d-old nulliparous and 10-, 15-, and 20-d-old nulliparous and parous female Aedes aegypti (L.), Anopheles albimanus (Weidemann), and Anopheles quadrimaculatus Say sensu lato. Mean protection time was shortest against An. albimanus (1.6 h) and An. quadrimaculatus (1.5 h) and longest against Ae. aegypti (6.5 h), but was not significantly influenced by mosquito age or parity. Mean percentage of biting at repellent failure time was highest in An. albimanus (14.2%), followed by An. quadrimaculatus (7.0%) and Ae. aegypti (2.9%), was higher in parous females (10.8%) than in nulliparous females (5.9%), and was highest overall (35%) in 20-d-old parous An. albimanus. Interaction between mosquito species and parity and between parity and age factors, respectively, resulted from a significant decrease in percentage of biting by parous An. quadrimaculatus compared with other females, and a significant increase in biting by 20-d-old parous females compared with other females. The main finding of this study is that repellent protection time is unaffected by parity; this is important because parous mosquitoes are the primary target of personal-protection measures in disease-endemic areas. When repellent failure did occur, there was a higher risk of bite by old, parous An. albimanus than for any other species, age, or parity grouping of females.

Robust Manipulations of Pest Insect Behavior Using Repellents and Practical Application for Integrated Pest Management.

Science.gov (United States)

Wallingford, Anna K; Cha, Dong H; Linn, Charles E; Wolfin, Michael S; Loeb, Gregory M

2017-10-01

In agricultural settings, examples of effective control strategies using repellent chemicals in integrated pest management (IPM) are relatively scarce compared to those using attractants. This may be partly due to a poor understanding of how repellents affect insect behavior once they are deployed. Here we attempt to identify potential hallmarks of repellent stimuli that are robust enough for practical use in the field. We explore the literature for success stories using repellents in IPM and we investigate the mechanisms of repellency for two chemical oviposition deterrents for controlling Drosophila suzukii Matsumura, a serious pest of small fruit crops. Drosophila suzukii causes injury by laying her eggs in ripening fruit and resulting larvae make fruit unmarketable. In caged choice tests, reduced oviposition was observed in red raspberry fruit treated with volatile 1-octen-3-ol and geosmin at two initial concentrations (10% and 1%) compared to untreated controls. We used video monitoring to observe fly behavior in these caged choice tests and investigate the mode of action for deterrence through the entire behavioral repertoire leading to oviposition. We observed fewer visitors and more time elapsed before flies first landed on 1-octen-3-ol-treated fruits than control fruits and concluded that this odor primarily inhibits behaviors that occur before D. suzukii comes in contact with a potential oviposition substrate (precontact). We observed some qualitative differences in precontact behavior of flies around geosmin-treated fruits; however, we concluded that this odor primarily inhibits behaviors that occur after D. suzukii comes in contact with treated fruits (postcontact). Field trials found reduced oviposition in red raspberry treated with 1-octen-3-ol and a combination of 1-octen-3-ol and geosmin, but no effect of geosmin alone. Recommendations for further study of repellents for practical use in the field are discussed. © The Authors 2017. Published by

The use of concentrated heat after insect bites/stings as an alternative to reduce swelling, pain, and pruritus: an open cohort-study at German beaches and bathing-lakes

Directory of Open Access Journals (Sweden)

Müller C

2011-12-01

Full Text Available Christian Müller1,*, Beatrice Großjohann1,*, Lutz Fischer2,*1Department of Medical Science and Operations, RIEMSER Arzneimittel AG, An der Wiek 7, 17489 Greifswald, 2Department of Anesthesiology and Intensive Medicine, University Greifswald, Friedrich-Loeffler-Straße 23b, 17493 Greifswald, Germany *These authors contributed equally to this workBackground: Swelling, pain, and pruritus are the most relevant symptoms after insect bites/stings. Glucocorticoids and antihistamines are well established in insect sting treatment. Bite Away® is a CE-certified medical device of class 2A (noninvasive device intended for administration to the body, which exchanges energy with the patient in a therapeutic manner to reduce swelling, pruritus, and pain after insect bites/stings via non-invasive administration of concentrated heat to the skin. We therefore performed a prospective, non-interventional, single-arm cohort study with 146 volunteers using the visual analog scale (VAS for insect bites/stings to study the reduction of swelling, pruritus, and pain. Demographic data, time from insect sting to treatment, number and duration of administrations of concentrated heat, relevant symptoms, and the development of a VAS score of swelling, pruritus, and pain on baseline, after 2, 5, and 10 minutes after administration, were registered.Results: In total 146 subjects with a mean age of 29.4 ± 20.7 years (range 2–81 were enrolled in the study. Ninety-three (63.7% of the subjects were stung by wasps, 33 (22.6% of the subjects were bitten by mosquitoes, and eight suffered bee stings (5.3%. VAS score swelling decreased with statistical significance after the use of Bite Away® from 4 before treatment to 2 and 1 after 2–5 and 10 minutes, respectively. VAS pain score was 6 before treatment, 2 after 2 minutes, 1 after 5 minutes, and 0 after 10 minutes (median. VAS pruritus score was only available for 52 (35.2% of the patients. The score decreased from 5 before

Seasonal differences in cytokine expression in the skin of Shetland ponies suffering from insect bite hypersensitivity

NARCIS (Netherlands)

Meulenbroeks, C.; Meide, van der N.M.A.; Zaiss, D.M.W.; Oldruitenborgh-Oosterbaan, M.M.S.; Lugt, van der J.J.; Smak, J.; Rutten, V.P.M.G.; Willemse, T.

2013-01-01

Insect bite hypersensitivity (IBH) in horses is a seasonal, IgE-mediated, pruritic skin disorder primarily caused by Culicoides spp. We hypothesize that a mixed Th2/Th1-type immune status, off season, alters into Th2-dominated immune reactivity in the skin of IBH-affected ponies in the IBM season.

Spatial repellency screening in a high-throughput apparatus with Aedes aegypti and Anopheles gambiae

Science.gov (United States)

Spatial repellents are essential for personal protection against mosquitoes, such as Aedes aegypti and Anopheles gambiae, to reduce annoyance biting and transmission of mosquito-borne diseases. The number of safe and effective repellents, including DEET, picaridin, and IR3535, is limited and contin...

[Field efficacy of repellent formulation containing para-menthane-3,8-diol and lemongrass against Culicoides pachymerus (Diptera: Ceratopogonidae) in Colombia].

Science.gov (United States)

Santamaría, Erika; Cabrera, Olga Lucía; Zipa, Yaneth; Pardo, Raúl Hernando

2012-09-01

Culicoides pachymerus is a major pest species for the inhabitants of the western Boyacá province of Colombia. The effect of a repellent lotion based on p-menthane-3,8-diol (16%) and lemongrass oil (2%) was evaluated against the bites of C. pachymerus. The repellent lotion was compared simultaneously with a control (no treatment) by human landing catches of C. pachymerus on the forearms of paired volunteers situated near human dwellings. Protection percentage and protection time for 3 to 6 h after repellent application was calculated. The test was repeated ten times. Only two females of C. pachymerus were collected on arms with the repellent treatment. In contrast, the mean biting rate in the untreated control was 47.7 midges/person/10 min. Mean protection percentage of the repellent was 100% up to 4 h and 99.5% up to 5 h. Protection time was 332.2 and 338.2 min in the two replicates where bites of C. pachymerus were confirmed. In the remaining eight replicates protection time exceeded the test duration. The repellent showed high efficacy against C. pachymerus, up to 5 h post-application.

Using Insect Repellents Safely and Effectively

Science.gov (United States)

... Directory Planning, Budget and Results Jobs and Internships Headquarters Offices Regional Offices Labs and Research Centers Related ... repellent product label. This registration number means the company provided EPA with technical information on the effectiveness ...

Field assessment of a novel spatial repellent for malaria control: a feasibility and acceptability study in Mondulkiri, Cambodia.

Science.gov (United States)

Liverani, Marco; Charlwood, Jacques Derek; Lawford, Harriet; Yeung, Shunmay

2017-10-13

Large-scale use of insecticide-treated nets and indoor residual spraying have contributed to a significant decrease in malaria transmission worldwide. Further reduction and progress towards elimination, however, require complementary control measures which can address the remaining gaps in protection from mosquito bites. Following the development of novel pyrethroids with high knockdown effects on malaria vectors, programmatic use of spatial repellents has been suggested as one potential strategy to fill the gaps. This report explores social and contextual factors that may influence the relevance, uptake and sustainable use of a spatial repellent in two remote villages in Mondulkiri province, Cambodia, with endemic malaria transmission. The repellent consisted of polyethylene emanators, held in an open plastic frame and impregnated with 10% metofluthrin. In a baseline survey, 90.9% of households in Ou Chra (n = 30/33) and 96.6% in Pu Cha (n = 57/59) were interviewed. Behavioural data were collected for all household occupants (n = 448). In both villages, there were times and places in which people remained exposed to mosquito bites. Prior to the installation of the repellent, 50.6 and 59.5% of respondents noted that bites occurred "very often" inside the house and in the outdoor area surrounding the house, respectively. Indoor biting was reported to occur more frequently in the evening, followed by at night, while outdoor biting occurred more frequently in the early morning. In a follow-up survey, spatial repellents were well received in both villages, although 63.2% of respondents would not replace bed nets with repellents. Most participants (96.6%) were willing to use the product again; the mean willingness to pay was US$ 0.3 per unit. A preference for local procurement methods emerged. Widespread use of spatial repellents would not fill all protective gaps, but, if their entomological efficacy can be ascertained, outdoor application has the potential to

Analysing the Repellents Using EDXRF Method

International Nuclear Information System (INIS)

Khin Mi Mi; Khin Yi; Sein Htoon

2004-05-01

Determination of elemental contents in neem oil was evaluated using EDXRF.The comparsion on elemental concentrations of mosquito repellents cream, lotion and neem oil had been made. Where the neem oil was applied to the exposed body, it was found that the neem oil gives the protection action from the bites of mosquitoes

Field evaluation of the Off! Clip-on Mosquito Repellent (metofluthrin) against Aedes albopictus and Aedes taeniorhynchus (Diptera: Culicidae) in northeastern Florida.

Science.gov (United States)

Xue, Rui-De; Qualls, Whitney A; Smith, Michael L; Gaines, Marcia K; Weaver, James H; Debboun, Mustapha

2012-05-01

Repellent efficacy of the Off! Clip-on Mosquito Repellent device (S. C. Johnson and Son, Inc., Racine, WI) containing Metofluthrin was evaluated on six human volunteers against the container-breeding mosquito Aedes albopictus (Skuse) and the salt marsh mosquito Aedes taeniorhynchus (Wiedemann) at two field locations in northeastern Florida. The device repelled mosquitoes by releasing a vaporized form of the pyrethroid insecticide metofluthrin ([AI] 31.2%) and provided 70% protection from Ae. albopictus bites for > 3 h. For the second field trial, a repellent device that was used in the first trial was tested after being open for >1 wk. This device provided 79% protection from Ae. taeniorhynchus bites for 3 h. Our field results showed that the repellent device was 70 and 79% effective at repelling Ae. albopictus and Ae. taeniorhynchus from human test subjects in both field locations in northeastern Florida.

Manufacturing of fuel gas and organic compost containing repellents for insects and other pests, by double fermentation

Energy Technology Data Exchange (ETDEWEB)

de Farias, R.

1976-07-27

Solid waste such as selected trash, harvest residues, and manure are fermented in 2 stages (aerobic fermentation at 80/sup 0/ for 8 to 15 days and anaerobic for 35 to 60 days) to produce a CH/sub 4/-contg. fuel gas with a calorific value of approx. 9500 cal/m/sup 3/, and an organic solid which has repellent effects on insects and other predators. The anaerobic fermentation is carried out in digestors with self-regulable hydraulic seals.

Comparison of the effect of two excipients (karite nut butter and vaseline on the efficacy of Cocos nucifera, Elaeis guineensis and Carapa procera oil-based repellents formulations against mosquitoes biting in Ivory Coast

Directory of Open Access Journals (Sweden)

Konan Y.L.

2003-06-01

Full Text Available Repellents in the form of dermal pomades are recommended as a protection against awakening and bedtime mosquito bites. If synthesis repellents are available, they are nevertheless not common and the prices remain out of reach for the communities concerned. The people therefore have to resort more and more to traditional concoctions, some of which have been shown to be effective. After demonstrating that oil-based formulations (lotions, creams, pomades of Cocos nucifera (coconut, Elaeis guineensis (oil palm and Carapa procera (gobi were effective against mosquitoes, it became necessary to study the impact of the two excipients used in their manufacture, on the effectiveness of the repellents. Experiments were carried with Anopheles gambiae and Aedes aegypti under lobaratory conditions and any other mosquitoes collected under field conditions in Ivory Coast. The laboratory results indicate that the average protection times obtained with formulations with karite nut butter as excipient (54.8 ± 37.0 mn and 74.6 ± 26.4 mn respectively on An. gambiae and Ae. aegypti are higher than those recorded with vaseline as excipient (respectively 42.7 ± 30.0 mn and 60.8 ± 33.9 mn. On the other hand, under field conditions, the biting rate percentage reduction obtained with the products with karite nut butter and vaseline excipient were similar (respectively 29.8 % and 35.9 % for all mosquitoes collected and 45.7 % and 47.4 % against An. gambiae. Nevertheless, the use of karite nut butter on repellent products should be encouraged because its sale price is very lower (10 time less than the vaseline's.

Comparison of the effect of two excipients (karite nut butter and vaseline) on the efficacy of Cocos nucifera, Elaeis guineensis and Carapa procera oil-based repellents formulations against mosquitoes biting in Ivory Coast.

Science.gov (United States)

Konan, Y L; Sylla, M S; Doannio, J M; Traoré, S

2003-06-01

Repellents in the form of dermal pomades are recommended as a protection against awakening and bedtime mosquito bites. If synthesis repellents are available, they are nevertheless not common and the prices remain out of reach for the communities concerned. The people therefore have to resort more and more to traditional concoctions, some of which have been shown to be effective. After demonstrating that oil-based formulations (lotions, creams, pomades) of Cocos nucifera (coconut), Elaeis guineensis (oil palm) and Carapa procera (gobi) were effective against mosquitoes, it became necessary to study the impact of the two excipients used in their manufacture, on the effectiveness of the repellents. Experiments were carried with Anopheles gambiae and Aedes aegypti under lobaratory conditions and any other mosquitoes collected under field conditions in Ivory Coast. The laboratory results indicate that the average protection times obtained with formulations with karite nut butter as excipient (54.8 +/- 37.0 mn and 74.6 +/- 26.4 mn respectively on An. gambiae and Ae. aegypti) are higher than those recorded with vaseline as excipient (respectively 42.7 +/- 30.0 mn and 60.8 +/- 33.9 mn). On the other hand, under field conditions, the biting rate percentage reduction obtained with the products with karite nut butter and vaseline excipient were similar (respectively 29.8% and 35.9% for all mosquitoes collected and 45.7% and 47.4% against An. gambiae). Nevertheless, the use of karite nut butter on repellent products should be encouraged because its sale price is very lower (10 time less) than the vaseline's.

Field trial on the spatial repellency of metofluthrin-impregnated plastic strips for mosquitoes in shelters without walls (beruga) in Lombok, Indonesia.

Science.gov (United States)

Kawada, Hitoshi; Maekawa, Yoshihide; Takagi, Masahiro

2005-12-01

Field trials on the spatial repellency of metofluthrin-impregnated plastic strips for mosquitoes present in shelters without walls (beruga) were carried out in Lombok, Indonesia. A major reduction in the incidence of human biting by Culex quinquefasciatus was achieved, and the use of two strips per beruga repelled >60% of the mosquitoes for at least 11 wk while four strips repelled >60% of the mosquitoes for more than 15 weeks. The technique was found to be a practical long-term solution for the prevention of mosquito bites without using electricity or heat to evaporate the metofluthrin.

Identifying Insect Bites and Stings

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... Editor & Contributors Sponsors Sponsorship Opportunities Spread the Word Shop AAP Find a Pediatrician Health Issues Conditions Abdominal ... birdbaths) and are attracted by bright colors and sweat. Bites result in stinging sensation followed by a ...

Bug bites and stings: When to see a dermatologist

Medline Plus

Full Text Available ... follow the instructions on the repellent and reapply as directed. If you are also wearing sunscreen, apply ... Do not use sunscreen that contains insect repellent, as sunscreen must be applied liberally and often while ...

Plant defense against insect herbivores

DEFF Research Database (Denmark)

Fürstenberg-Hägg, Joel; Zagrobelny, Mika; Bak, Søren

2013-01-01

, defense compounds. These bioactive specialized plant defense compounds may repel or intoxicate insects, while defense proteins often interfere with their digestion. Volatiles are released upon herbivory to repel herbivores, attract predators or for communication between leaves or plants, and to induce......Plants have been interacting with insects for several hundred million years, leading to complex defense approaches against various insect feeding strategies. Some defenses are constitutive while others are induced, although the insecticidal defense compound or protein classes are often similar...... defense responses. Plants also apply morphological features like waxes, trichomes and latices to make the feeding more difficult for the insects. Extrafloral nectar, food bodies and nesting or refuge sites are produced to accommodate and feed the predators of the herbivores. Meanwhile, herbivorous insects...

Structure-activity relationship studies on the mosquito toxicity and biting deterrency of callicarpenal derivatives.

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Cantrell, Charles L; Klun, Jerome A; Pridgeon, Julia; Becnel, James; Green, Solomon; Fronczek, Frank R

2009-04-01

Callicarpenal (=13,14,15,16-tetranorclerod-3-en-12-al=[(1S,2R,4aR,8aR)-1,2,3,4,4a,7,8,8a-octahydro-1,2,4a,5-tetramethylnaphthalen-1-yl]acetaldehyde; 1) has previously demonstrated significant mosquito bite-deterring activity against Aedes aegypti and Anopheles stephensi in addition to repellent activity against host-seeking nymphs of the blacklegged tick, Ixodes scapularis. In the present study, structural modifications were performed on callicarpenal (1) in an effort to understand the functional groups necessary for maintaining and/or increasing its activity and to possibly lead to more effective insect control agents. All modifications in this study targeted the C(12) aldehyde or the C(3) alkene functionalities or combinations thereof. Mosquito biting deterrency appeared to be influenced most by C(3) alkene modification as evidenced by catalytic hydrogenation that resulted in a compound having significantly less effectiveness than 1 at a test amount of 25 nmol/cm2. Oxidation and/or reduction of the C(12) aldehyde did not diminish mosquito biting deterrency, but, at the same time, none of the modifications were more effective than 1 in deterring mosquito biting. Toxicities of synthesized compounds towards Ae. aegypti ranged from an LD50 value of 2.36 to 40.11 microg per mosquito. Similarly, LD95 values ranged from a low of 5.59 to a high of 104.9 microg.

AN INVESTIGATION OF INSECT OVIPOSITING REPELLENT ACTIVITY OF ANDROGRAPHIS PANICULATA NESS, ACACIA AURICULIFORMIS AND PIPER BETLE LINN LEAVES EXTRACTS TO BATROCERA CARAMBOLAE

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Nurcahyo Iman Prakoso

2017-12-01

Full Text Available Batrocera carambolae was one of the main pests in some types of fruits. This pest attack resulted in quantitative damage in the form of fall of young fruit and qualitatively in the form of fruit to rot and contains maggots. This research was conducted to determine selected extract from Andrographis Paniculata Ness, Piper betle Linn and Acacia auriculiformis leaves which have repellent activity for Batrocera carambolae. Nine extracts from the maceration process of the three leaves were evaluated by placing the extracts and flies together in the cage. The ethanol, ethyl acetate, and n-hexane extracts from Andrographis Paniculata Ness, Piper betle Linn and Acacia auriculiformis leaves were applied to the test pieces and fed into a cage containing 10 male and female flies. From observation, N-hexane extracts from Andrographis Paniculata Ness and Piper betle Linn leaves and ethyl acetate extracts from Acacia auriculiformis leaf having good activity as repellent and potentially to be used as a insect ovipositing repellent of Batrocera carambolae.

N,N-diethyl phenylacetamide (DEPA): A safe and effective repellent for personal protection against hematophagous arthropods.

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Kalyanasundaram, Muthuswami; Mathew, Nisha

2006-05-01

Repellents play an important role in protecting humans from the bites of insect pests. An effective and safe repellent will be useful in reducing human-vector contact and thereby help in the interruption of vector borne disease transmission. Because of the unavailability of m-toluic acid in India for the manufacture of N,N-diethyl m-toluamide (DEET), there is a need to develop an alternate effective and safe insect repellent. In total, 120 substituted amides were synthesized and tested for repellency at 1.0 mg/cm2 under laboratory conditions. Among these amides, N,N-diethyl phenylacetamide (DEPA), applied at 1.0 mg/cm2 in different oil bases, was found to exhibit promising repellency (6-8 h) in the laboratory when tested against Aedes aegypti (L.) The repellent DEPA was evaluated on army personnel in comparison with dimethylphthalate (DMP) and DEET against mosquitoes, black flies, and land leeches under field condition in the North-East Frontier area of India. Both DEPA and DEET displayed broad-spectrum repellency. DEPA was more effective than DMP against all test organisms. However, no significant difference was noticed between DEPA and DEET for repellency at 0.25 and 0.5 mg/cm2 against black flies and mosquitoes. DMP was the least effective among the three compounds in the field studies. The relative potency of DEPA in comparison with DEET and DMP for repellency against Phlebotomine sand flies also was determined. At 0.1 mg/cm2, both DEPA and DEET were found to be equally effective with a protection time from 4.37 +/- 0.08 to 4.45 +/- 0.15 h. Both compounds were significantly more effective than DMP. At 0.2 mg/cm2, DEPA and DEET provided protection times of 6.52 +/- 0.08 and 7.15 +/- 0.15 h, respectively. DEPA was formulated into a vanishing cream, a pharmacologically safe polymer-based liquid, and a liposphere lotion. The vanishing cream and the two-polymer liquid formulations enhanced protection times from 4.4 to 6.5 and 7.13 h, respectively, compared with an

Travelers' Health: Protection against Mosquitoes, Ticks, and Other Arthropods

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... Clots Bug Bites Evite las picaduras de insectos Business Travel Cold Climates Counterfeit Medicines Cruise Ship Travel ... lactating women. Useful Links Insect Repellents: Use and Effectiveness ... from these pests. The costs of ridding a personal residence of these insects ...

Aquatic insect predators and mosquito control.

Science.gov (United States)

Shaalan, Essam Abdel-Salam; Canyon, Deon V

2009-12-01

Mosquitoes are serious biting pests and obligate vectors of many vertebrate pathogens. Their immature larval and pupal life stages are a common feature in most tropical and many temperate water bodies and often form a significant proportion of the biomass. Control strategies rely primarily on the use of larvicides and environmental modification to reduce recruitment and adulticides during periods of disease transmission. Larvicides are usually chemical but can involve biological toxins, agents or organisms. The use of insect predators in mosquito control has been exploited in a limited fashion and there is much room for further investigation and implementation. Insects that are recognized as having predatorial capacity with regard to mosquito prey have been identified in the Orders Odonata, Coleoptera, Diptera (primarily aquatic predators), and Hemiptera (primarily surface predators). Although their capacity is affected by certain biological and physical factors, they could play a major role in mosquito control. Furthermore, better understanding for the mosquitoes-predators relationship(s) could probably lead to satisfactory reduction of mosquito-borne diseases by utilizing either these predators in control programs, for instance biological and/or integrated control, or their kairomones as mosquitoes' ovipoisting repellents. This review covers the predation of different insect species on mosquito larvae, predator-prey-habitat relationships, co-habitation developmental issues, survival and abundance, oviposition avoidance, predatorial capacity and integrated vector control.

Fire Ant Bites

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... Favorite Name: Category: Share: Yes No, Keep Private Fire Ant Bites Share | Fire ants are aggressive, venomous insects that have pinching ... across the United States, even into Puerto Rico. Fire ant stings usually occur on the feet or ...

Evaluation of the laboratory mouse model for screening topical mosquito repellents.

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Rutledge, L C; Gupta, R K; Wirtz, R A; Buescher, M D

1994-12-01

Eight commercial repellents were tested against Aedes aegypti 0 and 4 h after application in serial dilution to volunteers and laboratory mice. Results were analyzed by multiple regression of percentage of biting (probit scale) on dose (logarithmic scale) and time. Empirical correction terms for conversion of values obtained in tests on mice to values expected in tests on human volunteers were calculated from data obtained on 4 repellents and evaluated with data obtained on 4 others. Corrected values from tests on mice did not differ significantly from values obtained in tests on volunteers. Test materials used in the study were dimethyl phthalate, butopyronoxyl, butoxy polypropylene glycol, MGK Repellent 11, deet, ethyl hexanediol, Citronyl, and dibutyl phthalate.

Bug bites and stings: When to see a dermatologist

Medline Plus

Full Text Available ... re visiting areas with known insect-borne diseases, it’s important to take steps to reduce your risk. ... also wearing sunscreen, apply your sunscreen first, let it dry, and then apply the insect repellent. Do ...

Repellency of essential oils extracted from Thai native plants against Aedes aegypti (Linn.) and Culex quinquefasciatus (Say).

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Phukerd, Ubol; Soonwera, Mayura

2014-09-01

Repellent activity of essential oils derived from 10 Thai native plants, belonging to three families were evaluated against female Aedes aegypti and Culex quinquefasciatus and to compare them with a commercial chemical repellents (DEET; N,N-diethyl-3-methylbenzamide 20% w/w; Sketolene Shield). Each test repellent was applied at 1, 5, and 10% concentrations for testing by arm in cage method. The results showed significant differences in repellency among the repellents by mosquito species. The protection time of the essential oils against Ae. aegypti ranged from 3 to 30 min. According to the Culex mosquito, it showed the protection time ranged from 3 to 260 min. 10 % Boesenbergia rotunda essential oil provided the best efficiency, in which protection time was 4.3 h as equal as DEET. The essential oils which exhibited protection time more than 2 h were those of 10% Zingiber zerumbet, Litsea petiolata, Curcuma zedoaria, and Zingiber cassumunar essential oils (3.1, 2.8, 2.6, and 2.3 h, respectively). The biting percentage ranged from 0.9 to 18.0% and 0.8 to 3.6% against Ae. aegypti and Cx. quinquefasciatus, respectively. The results revealed that the potential of essential oil extracted from B. rotunda, Z. zerumbet, L. petiolata, C. zedoaria, and Z. cassumunar had attributes of good repellent and deterred biting. We recommend the five essential oils for further study to develop as commercial repellents.

An Investigation of Insect Ovipositing Repellent Activity of Andrographis paniculata Ness, Acacia auriculiformis and Piper betle Linn Leaves Extracts to Batrocera carambolae

Directory of Open Access Journals (Sweden)

Nurcahyo Iman Prakoso

2018-03-01

Full Text Available Batrocera carambolae was one of the main pests in some types of fruits. This pest attack resulted in quantitative damage in the form of fall of young fruit and qualitatively in the form of fruit to rot and contains maggots. This research was conducted to determine selected extract from Andrographis Paniculata Ness, Piper betle Linn and Acacia auriculiformis leaves which have repellent activity for Batrocera carambolae. Nine extracts from the maceration process of the three leaves were evaluated by placing the extracts and flies together in the cage. The ethanol, ethyl acetate, and n-hexane extracts from Andrographis Paniculata Ness, Piper betle Linn and Acacia auriculiformis leaves were applied to the test pieces and fed into a cage containing 10 male and female flies. From observation, N-hexane extracts from Andrographis Paniculata Ness and Piper betle Linn leaves and ethyl acetate extracts from Acacia auriculiformis leaf  having good activity as repellent and potentially to be used as a insect ovipositing repellent of Batrocera carambolae.

Studies on repellent activity of seed oils alone and in combination on mosquito, Aedes aegypti.

Science.gov (United States)

Mukesh, Y; Savitri, P; Kaushik, R; Singh, N P

2014-09-01

The study was undertaken to investigate the relative repellency of Pongamia pinnata and Azadirachta indica seed oils on vector mosquito, Aedes aegypti under laboratory conditions. The repellents were formulated into 3 groups: seed oils, their mixture and combination of seed oils with three carrier oils viz. olive, mustard and coconut oil. Different formulations of each oil were tested at the concentrations of 1% and 5% on human baits. Efficiency was assessed, based on the total protection time; biting rate and percent protection provided by each formulation. Results showed that 5% formulation of the Pongamia pinnata and Azadirachta indica seed oils, mixed in 1:1 ratio exhibited highest percentage repellency of 85%, protection time of 300 min and bite rate of 6%. 5% concentration of A. indica and P. pinnata seed oil in mustard oil base offered 86.36% and 85% protection respectively with total protection time of 230 and 240 min respectively. The study confirms that Azadirachta indica and Pongamia pinnata have mosquito-repellent potential. When mixed in different ratios or with some carrier oil their efficacy increases 2-fold in some cases. These formulations are very promising for topical use (> 5 hrs complete protection) and are comparable to the protection provided by advanced Odomos mosquito repellent cream available commercially and thus are recommended for field trial.

DEET, Active Substance Of Repellent That Effective And Safe For Travelers

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Made Ika Lestari

2013-10-01

Full Text Available Normal 0 false false false EN-US X-NONE X-NONE Increased flow of tourism to the tropics and the changing patterns of vector-borne diseases require increased protection against insects. To prevent transmission of the disease is done several ways that increase self-protection by using mosquito repellent can protect travelers while outdoor activities. One option is active formula mosquito repellent DEET. The purpose of this paper is to determine the best dosage forms for travelers DEET., To determine the effectiveness and safety of DEET and to know the workings of the active ingredient DEET. The method of writing is the literature search through medical journals and articles. From the search was obtained, the most appropriate anti-mosquito travelers to use while on the move outdoors in the dosage form is DEET lotion applied to the skin as the most secure and durable because it does not easily evaporate. Mosquito repellent containing DEET has been proven effective and safe for use in adults, children, and pregnant women, but should still follow the instructions. The workings of the mosquito repellent DEET mosquito dispel is manipulating 1-Octen-3-ol used by mosquitoes to detect human presence. So ORN (olfactory receptor neurons in the mosquitoes can not respond anymore to the maximum, so that people avoid the bites nyamuk. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New

The same ELA class II risk factors confer equine insect bite hypersensitivity in two distinct populations.

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Andersson, Lisa S; Swinburne, June E; Meadows, Jennifer R S; Broström, Hans; Eriksson, Susanne; Fikse, W Freddy; Frey, Rebecka; Sundquist, Marie; Tseng, Chia T; Mikko, Sofia; Lindgren, Gabriella

2012-03-01

Insect bite hypersensitivity (IBH) is a chronic allergic dermatitis common in horses. Affected horses mainly react against antigens present in the saliva from the biting midges, Culicoides ssp, and occasionally black flies, Simulium ssp. Because of this insect dependency, the disease is clearly seasonal and prevalence varies between geographical locations. For two distinct horse breeds, we genotyped four microsatellite markers positioned within the MHC class II region and sequenced the highly polymorphic exons two from DRA and DRB3, respectively. Initially, 94 IBH-affected and 93 unaffected Swedish born Icelandic horses were tested for genetic association. These horses had previously been genotyped on the Illumina Equine SNP50 BeadChip, which made it possible to ensure that our study did not suffer from the effects of stratification. The second population consisted of 106 unaffected and 80 IBH-affected Exmoor ponies. We show that variants in the MHC class II region are associated with disease susceptibility (p (raw) = 2.34 × 10(-5)), with the same allele (COR112:274) associated in two separate populations. In addition, we combined microsatellite and sequencing data in order to investigate the pattern of homozygosity and show that homozygosity across the entire MHC class II region is associated with a higher risk of developing IBH (p = 0.0013). To our knowledge this is the first time in any atopic dermatitis suffering species, including man, where the same risk allele has been identified in two distinct populations.

Laboratory and semi-field evaluations of two (Transfluthrin) spatial repellent devices against Aedes aegypti (L.) (Diptera: Culicidae)

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Two transfluthrin-based spatial repellent products (Raid Dual Action Insect Repellent and Home Freshener and Raid Shield (currently not commercially available), SC Johnson, Racine WI) were evaluated for spatial repellent effects against female Aedes aegypti (L.) mosquitoes underlaboratory (wind tunn...

Biting behaviour of African malaria vectors: 1. where do the main vector species bite on the human body?

Science.gov (United States)

Braack, Leo; Hunt, Richard; Koekemoer, Lizette L; Gericke, Anton; Munhenga, Givemore; Haddow, Andrew D; Becker, Piet; Okia, Michael; Kimera, Isaac; Coetzee, Maureen

2015-02-04

Malaria control in Africa relies heavily on indoor vector management, primarily indoor residual spraying and insecticide treated bed nets. Little is known about outdoor biting behaviour or even the dynamics of indoor biting and infection risk of sleeping household occupants. In this paper we explore the preferred biting sites on the human body and some of the ramifications regarding infection risk and exposure management. We undertook whole-night human landing catches of Anopheles arabiensis in South Africa and Anopheles gambiae s.s. and Anopheles funestus in Uganda, for seated persons wearing short sleeve shirts, short pants, and bare legs, ankles and feet. Catches were kept separate for different body regions and capture sessions. All An. gambiae s.l. and An. funestus group individuals were identified to species level by PCR. Three of the main vectors of malaria in Africa (An. arabiensis, An. gambiae s.s. and An. funestus) all have a preference for feeding close to ground level, which is manifested as a strong propensity (77.3% - 100%) for biting on lower leg, ankles and feet of people seated either indoors or outdoors, but somewhat randomly along the lower edge of the body in contact with the surface when lying down. If the lower extremities of the legs (below mid-calf level) of seated people are protected and therefore exclude access to this body region, vector mosquitoes do not move higher up the body to feed at alternate body sites, instead resulting in a high (58.5% - 68.8%) reduction in biting intensity by these three species. Protecting the lower limbs of people outdoors at night can achieve a major reduction in biting intensity by malaria vector mosquitoes. Persons sleeping at floor level bear a disproportionate risk of being bitten at night because this is the preferred height for feeding by the primary vector species. Therefore it is critical to protect children sleeping at floor level (bednets; repellent-impregnated blankets or sheets, etc

Evaluation of a Noncontact, Alternative Mosquito Repellent Assay System.

Science.gov (United States)

Tisgratog, Rungarun; Kongmee, Monthathip; Sanguanpong, Unchalee; Prabaripai, Atchariya; Bangs, Michael J; Chareonviriyaphap, Theeraphap

2016-09-01

A novel noncontact repellency assay system (NCRAS) was designed and evaluated as a possible alternative method for testing compounds that repel or inhibit mosquitoes from blood feeding. Deet and Aedes aegypti were used in a controlled laboratory setting. Using 2 study designs, a highly significant difference were seen between deet-treated and untreated skin placed behind the protective screens, indicating that deet was detected and was acting as a deterrence to mosquito landing and probing behavior. However, a 2nd study showed significant differences between protected (behind a metal screen barrier) and unprotected (exposed) deet-treated forearms, indicating the screen mesh might restrict the detection of deet and thus influences landing/biting response. These findings indicate the prototype NCRAS shows good promise but requires further evaluation and possible modification in design and testing protocol to achieve more desirable operational attributes in comparison with direct skin-contact repellency mosquito assays.

Repellency of essential oil of Piper aduncum against Aedes albopictus in the laboratory.

Science.gov (United States)

Misni, Norashiqin; Sulaiman, Sallehudin; Othman, Hidayatulfathi; Omar, Baharudin

2009-12-01

The repellent activity of Piper aduncum essential oil against Aedes albopictus was investigated under laboratory conditions with human volunteers. The lowest median effective dose (ED50) value was 1.5 microg/cm2 at 60 sec of exposure when compared to 90 sec (2.1 microg/cm2) and 120 sec (1.8 microg/cm2) of exposure. At 0.4 g, the essential oil gave a high protection (95.2%) against Ae. albopictus bites or landing at 2 h postapplication. The percentage of protection was reduced to 83.3% after 4 h, 64.5% after 6 h, and 51.6% after 8 h postapplication. As a comparison, treatment with 10% deet gave 100% protection against mosquito biting/landing for 4 h postapplication. There was no significant difference in percentage protection reduction between the plant extract and the commercial product deet, respectively (P = 0.739). The essential oil, which was not as good as deet, still gave moderate protection against Ae. albopictus biting even until 4 h postapplication. In conclusion, the P. aduncum essential oil has the potential to be used as a repellent against the dengue/dengue hemorrhagic fever vector, Ae. albopictus.

Repellency Effect of Essential Oils of Some Native Plants and Synthetic Repellents against Human Flea, Pulex irritans (Siphonaptera: Pulicidae

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Mohammad Bagher Ghavami

2017-04-01

Full Text Available Background: Fleas are important vectors of human and animal disease, and control measures for protection against their bites and flea-borne diseases are necessary.Methods: The essential oils (EOs of four native medicinal plants, Ziziphora tenuiore, Myrtus communis, Achillea wilhelmsii and Mentha piperita were isolated by hydrodistillation technique and analyzed by GC-MC. The repellent activity of EOs and synthetic compounds, DEET and permethrin, were assayed on human subjects against field col­lected fleas. The effective doses of 50% and 90% of EOs and synthetic compounds were estimated by probit analysis of dose and response regression line.Results: Analysis of EOs revealed about 19 major components. All oils were found to be more repellent (ED50 range= 208–955µg cm-2 than DEET and permethrin (ED50 range= 27–182 x 103 µg cm-2. Thyme and myrtle oils showed high repellent activities and among the total detected terpenes, thymol (36.26% and α- pinene (32.5% were the major components of those oils respectively.Conclusion: Low repellent potency of DEET and permethrin against fleas might be related to flea olfactory system and further molecular and electrophysiological studies are required to conceive new ideas for the discovery and de­velopment of the next generation of repellents. Based on high repellent activity of thyme and myrtle essential oils against Pulex irritans further studies should be staged to develop their appropriate effective formulations. Likewise, field trials should be carried out to evaluate the operational feasibility and dermal toxicity over a long period.

Equine allergy therapy: update on the treatment of environmental, insect bite hypersensitivity, and food allergies.

Science.gov (United States)

Marsella, Rosanna

2013-12-01

Allergies are common in horses. It is important to identify and correct as many factors as possible to control pruritus and make the patient comfortable. Culicoides hypersensitivity is a common component in allergic horses. The main treatment continues to be rigorous fly control and avoidance of insect bites. Environmental allergies are best addressed by early identification of the offending allergens and formulation of allergen-specific immunotherapy to decrease the need for rescue medications. Food allergy is best managed with food avoidance. Urticaria is one of the manifestations of allergic disease wherein detection of the triggering cause is essential for management. Copyright © 2013 Elsevier Inc. All rights reserved.

Too hard to swallow: a secret secondary defence of an aposematic insect.

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Wang, Lu-Yi; Huang, Wen-San; Tang, Hsin-Chieh; Huang, Lung-Chun; Lin, Chung-Ping

2018-01-25

Anti-predator strategies are significant components of adaptation in prey species. Aposematic prey are expected to possess effective defences that have evolved simultaneously with their warning colours. This study tested the hypothesis of the defensive function and ecological significance of the hard body in aposematic Pachyrhynchus weevils pioneered by Alfred Russel Wallace nearly 150 years ago. We used predation trials with Japalura tree lizards to assess the survivorship of 'hard' (mature) versus 'soft' (teneral) and 'clawed' (intact) versus 'clawless' (surgically removed) weevils. The ecological significance of the weevil's hard body was evaluated by assessing the hardness of the weevils, the local prey insects, and the bite forces of the lizard populations. The existence of toxins or deterrents in the weevil was examined by gas chromatography-mass spectrometry (GC-MS). All 'hard' weevils were instantly spat out after being bitten once and survived attacks by the lizards. In contrast, the 'soft' weevils were chewed and subsequently swallowed. The results were the same regardless of the presence or absence of the weevil's tarsal claws. The hardness of 'hard' Pachyrhynchus weevils was significantly higher than the average hardness of other prey insects in the same habitat and the mean bite forces of the local lizards. The four candidate compounds of the weevil identified by GC-MS had no known toxic or repellent functions against vertebrates. These results reveal that the hardness of aposematic prey functions as an effective secondary defence, and they provide a framework for understanding the spatio-temporal interactions between vertebrate predators and aposematic insect prey. © 2018. Published by The Company of Biologists Ltd.

Tips to Prevent Mosquito Bites

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... discourage mosquitoes, ticks and other biting insects from landing on you. Here are tips for other preventive ... CDC Mosquito Control Methods - NPIC Exit Top of Page Contact Us to ask a question, provide feedback, ...

Insect-resistant food packaging film development using cinnamon oil and microencapsulation technologies.

Science.gov (United States)

Kim, In-Hah; Han, Jaejoon; Na, Ja Hyun; Chang, Pahn-Sik; Chung, Myung Sub; Park, Ki Hwan; Min, Sea C

2013-02-01

Insect-resistant films containing a microencapsulated insect-repelling agent were developed to protect food products from the Indian meal moth (Plodia interpunctella). Cinnamon oil (CO), an insect repelling agent, was encapsulated with gum arabic, whey protein isolate (WPI)/maltodextrin (MD), or poly(vinyl alcohol) (PVA). A low-density polyethylene (LDPE) film was coated with an ink or a polypropylene (PP) solution that incorporated the microcapsules. The encapsulation efficiency values obtained with gum arabic, WPI/MD, and PVA were 90.4%, 94.6%, and 80.7%, respectively. The films containing a microcapsule emulsion of PVA and CO or incorporating a microcapsule powder of WPI/MD and CO were the most effective (P packaging for food products. The insect-repelling effect of cinnamon oil incorporated into LDPE films was more effective with microencapsulation. The system developed in this research with LDPE film may also be extended to other food-packaging films where the same coating platform can be used. This platform is interchangeable and easy to use for the delivery of insect-repelling agents. The films can protect a wide variety of food products from invasion by the Indian meal moth. © 2013 Institute of Food Technologists®

Essential oils of aromatic Egyptian plants repel nymphs of the tick Ixodes ricinus (Acari: Ixodidae).

Science.gov (United States)

El-Seedi, Hesham R; Azeem, Muhammad; Khalil, Nasr S; Sakr, Hanem H; Khalifa, Shaden A M; Awang, Khalijah; Saeed, Aamer; Farag, Mohamed A; AlAjmi, Mohamed F; Pålsson, Katinka; Borg-Karlson, Anna-Karin

2017-09-01

Due to the role of Ixodes ricinus (L.) (Acari: Ixodidae) in the transmission of many serious pathogens, personal protection against bites of this tick is essential. In the present study the essential oils from 11 aromatic Egyptian plants were isolated and their repellent activity against I. ricinus nymphs was evaluated Three oils (i.e. Conyza dioscoridis L., Artemisia herba-alba Asso and Calendula officinalis L.) elicited high repellent activity in vitro of 94, 84.2 and 82%, respectively. The most active essential oil (C. dioscoridis) was applied in the field at a concentration of 6.5 µg/cm 2 and elicited a significant repellent activity against I. ricinus nymphs by 61.1%. The most repellent plants C. dioscoridis, C. officinalis and A. herba-alba yielded essential oils by 0.17, 0.11 and 0.14%, respectively. These oils were further investigated using gas chromatography-mass spectrometry analysis. α-Cadinol (10.7%) and hexadecanoic acid (10.5%) were the major components of C. dioscoridis whereas in C. officinalis, α-cadinol (21.2%) and carvone (18.2%) were major components. Artemisia herba-alba contained piperitone (26.5%), ethyl cinnamate (9.5%), camphor (7.7%) and hexadecanoic acid (6.9%). Essential oils of these three plants have a potential to be used for personal protection against tick bites.

Prevention of Dengue fever through plant based mosquito repellent Clausena dentata (Willd.) M. Roem (Family: Rutaceae) essential oil against Aedes aegypti l. (Diptera: Culicidae) mosquito.

Science.gov (United States)

Rajkumar, S; Jebanesan, A

2010-03-01

Plant based repellent against mosquito borne diseases are used recently because synthetic repellents cause side effects like breathing problem, eye irritation, head ache, cough, etc. The use of natural products for dengue control would protect the environment, reduce dependence on expensive synthetic repellents and also generate local employment. Essential oil was isolated by steam distillation which was used against the bites of Aedes aegypti and duration of protection period was assessed. Skin-irritant potential test was also conducted on 25 healthy volunteers by using four-point scale. The increase in the concentrations of essential oil increased the mean protection time against the bites of Aedes aegypti. The lowest mean protection time was 180.0 min for 2.5% and highest time of 255.0 min for 10%. The mean score of zero for skin-irritant potential test for all the concentrations indicated that the essential oil did not cause irritation to human skin. Results indicated that the use of plant based repellent for the control of dengue fever would replace the currently used synthetic repellents which causes many side effects.

From Chemistry to Behavior. Molecular Structure and Bioactivity of Repellents against Ixodes ricinus Ticks.

Directory of Open Access Journals (Sweden)

Simone Del Fabbro

Full Text Available Tick-borne zoonoses are considered as emerging diseases. Tick repellents represent an effective tool for reducing the risk of tick bite and pathogens transmission. Previous work demonstrated the repellent activity of the phenylpropanoid eugenol against Ixodes ricinus; here we investigate the relationship between molecular structure and repellency in a group of substances related to that compound. We report the biological activity of 18 compounds varying for the presence/number of several moieties, including hydroxyl and methoxy groups and carbon side-chain. Each compound was tested at different doses with a bioassay designed to measure repellency against individual tick nymphs. Both vapor pressure and chemical features of the tested compounds appeared to be related to repellency. In particular, the hydroxyl and methoxy groups as well as the side-chain on the benzene ring seem to play a role. These results are discussed in light of available data on chemical perception in ticks. In the course of the study new repellent compounds were identified; the biological activity of some of them (at least as effective as the "gold standard" repellent DEET appears to be very promising from a practical point of view.

Field trial of the spatial repellency of metofluthrin-impregnated plastic strip against mosquitoes in shelters without walls (Beruga) in Lombok, Indonesia.

OpenAIRE

Kawada, Hitoshi; Maekawa, Yoshihide; Takagi, Masahiro

2005-01-01

Field trials on the spatial repellency of metofluthrin-impregnated plastic strips for mosquitoes present in shelters without walls (beruga) were carried out in Lombok, Indonesia. A major reduction in the incidence of human biting by Culex quinquefasciatus was achieved, and the use of two strips per beruga repelled >60% of the mosquitoes for at least 11 wk while four strips repelled >60% of the mosquitoes for more than 15 weeks. The technique was found to be a practical long-term solution for ...

Bug bites and stings: When to see a dermatologist

Medline Plus

Full Text Available ... MOC Recognized Credit Basic Derm Curriculum Teaching and learning guides ... layers of clothing with insect repellent containing the active ingredient Permethrin. Follow the directions carefully and allow ...

Pest repellent properties of ant pheromones

DEFF Research Database (Denmark)

Offenberg, Joachim

2012-01-01

of ant pheromones may be sufficient to repel pest insects from ant territories. The study of ant semiochemicals is in its infancy, yet, evidence for their potential use in pest management is starting to build up. Pheromones from four of five tested ant species have been shown to deter herbivorous insect...... prey and competing ant species are also deterred by ant deposits, whereas ant symbionts may be attracted to them. Based on these promising initial findings, it seems advisable to further elucidate the signaling properties of ant pheromones and to test and develop their use in future pest management....

Novel qsar combination forecast model for insect repellent coupling support vector regression and k-nearest-neighbor

International Nuclear Information System (INIS)

Wang, L.F.; Bai, L.Y.

2013-01-01

To improve the precision of quantitative structure-activity relationship (QSAR) modeling for aromatic carboxylic acid derivatives insect repellent, a novel nonlinear combination forecast model was proposed integrating support vector regression (SVR) and K-nearest neighbor (KNN): Firstly, search optimal kernel function and nonlinearly select molecular descriptors by the rule of minimum MSE value using SVR. Secondly, illuminate the effects of all descriptors on biological activity by multi-round enforcement resistance-selection. Thirdly, construct the sub-models with predicted values of different KNN. Then, get the optimal kernel and corresponding retained sub-models through subtle selection. Finally, make prediction with leave-one-out (LOO) method in the basis of reserved sub-models. Compared with previous widely used models, our work shows significant improvement in modeling performance, which demonstrates the superiority of the present combination forecast model. (author)

Repellency of Lantana camara (Verbenaceae) flowers against Aedes mosquitoes.

Science.gov (United States)

Dua, V K; Gupta, N C; Pandey, A C; Sharma, V P

1996-09-01

The repellent effect of Lantana camara flowers was evaluated against Aedes mosquitoes. Lantana flower extract in coconut oil provided 94.5% protection from Aedes albopictus and Ae. aegypti. The mean protection time was 1.9 h. One application of Lantana flower can provide more than 50% protection up to 4 h against the possible bites of Aedes mosquitoes. No adverse effects of the human volunteers were observed through 3 months after the application.

Chemical composition, insecticidal and insect repellent activity of Schinus molle L. leaf and fruit essential oils against Trogoderma granarium and Tribolium castaneum.

Science.gov (United States)

Abdel-Sattar, Essam; Zaitoun, Ahmed A; Farag, Mohamed A; Gayed, Sabah H El; Harraz, Fathalla M H

2010-02-01

Fruit and leaf essential oils of Schinus molle showed insect repellent and insecticidal activity against Trogoderma granarium and Tribolium castaneum. In these oils, 65 components were identified by GC-MS analysis. Hydrocarbons dominated the oil composition with monoterpenes occurring in the largest amounts in fruits and leaves, 80.43 and 74.84%, respectively. p-Cymene was identified as a major component in both oils. The high yield and efficacy of S. molle essential oil against T. granarium and T. castaneum suggest that it may provide leads for active insecticidal agents.

Ethnobotany of plants used as insecticides, repellents and ...

African Journals Online (AJOL)

An ethnobotanical study on plants used for the prevention and treatment of malaria was conducted to document the indigenous knowledge particularly associated with the use and conservation of anti-malarial, insecticide and insect repellent medicinal plants. In this study, five sampling sites were selected based on the ...

Determining Exposure Factors of Anti-Fogging, Dye, Disinfectant, Repellent, and Preservative Products in Korea.

Science.gov (United States)

Lee, Daeyeop; Kim, Joo-Hyon; Kim, Taksoo; Yoon, Hyojung; Jo, Areum; Lee, Byeongwoo; Lim, Hyunwoo; Kim, Pilje; Seo, Jungkwan

2018-01-30

Reliable exposure factors are essential to determine health risks posed by chemicals in consumer products. We analyzed five risk-concerned product categories (anti-fogging, dye, disinfectant, repellent, and preservative products) for 13 products (three car anti-fogging products, a lens anti-fogging product, two car dye products, two drain disinfectants, an air conditioner disinfectant, a chlorine-based disinfectant, a fabric repellent, an insect repellent for food, and a wood preservative) considered to be of high risk in order to determine exposure factors via web surveys and estimation of amount of product. Among the 3000 participants (1482 (49%) men) aged ≥19 years, drain disinfectants were used most frequently (38.2%); the rate of usage of the other products ranged between 1.1-24.0%. The usage rates for the consumer products differed by sex, age, income, and education. Some consumer products such as car and lens anti-fogging products, chlorine-based disinfectants, fabric repellents, and drain disinfectants were regularly used more than once a month, while car dye products, air conditioner disinfectants, insect repellents for food, and wood preservatives were not regularly used owing to the specific product purposes and seasonal needs. Our results could be used for managing or controlling chemical substances in consumer products and conducting accurate exposure assessments.

Novel in vitro diagnosis of equine allergies using a protein array and mathematical modelling approach: a proof of concept using insect bite hypersensitivity.

Science.gov (United States)

Marti, E; Wang, X; Jambari, N N; Rhyner, C; Olzhausen, J; Pérez-Barea, J J; Figueredo, G P; Alcocer, M J C

2015-10-15

Insect bite hypersensitivity (IBH) is a seasonal recurrent skin allergy of horses caused by IgE-mediated reactions to allergens present in the saliva of biting insects of the genus Culicoides, and possibly also Simulium and Stomoxys species. In this work we show that protein microarrays containing complex extracts and pure proteins, including recombinant Culicoides allergens, can be used as a powerful technique for the diagnosis of IBH. Besides the obvious advantages such as general profiling and use of few microliters of samples, this microarray technique permits automation and allows the generation of mathematical models with the calculation of individual risk profiles that can support the clinical diagnosis of allergic diseases. After selection of variables on influence on the projection (VIP), the observed values of sensitivity and specificity were 1.0 and 0.967, respectively. This confirms the highly discriminatory power of this approach for IBH and made it possible to attain a robust predictive mathematical model for this disease. It also further demonstrates the specificity of the protein array method on identifying a particular IgE-mediated disease when the sensitising allergen group is known. Copyright © 2015 Elsevier B.V. All rights reserved.

Rhanterium epapposum Oliv. essential oil: Chemical composition and antimicrobial,insect-repellent and anticholinesterase activities

Science.gov (United States)

Essential oils from Rhanterium epapposum Oliv. (Asteraceae) was investigated for its repellent, antimicrobial and acetyl- and butyrylcholine esterase inhibitory activities. The oil showed good repellent activity while oils demonstrated weak in antimicrobial and cholinesterase inhibitions. Terpenoids...

Factors influencing the use of topical repellents: implications for the effectiveness of malaria elimination strategies

NARCIS (Netherlands)

Gryseels, C.; Uk, S.; Sluydts, V.; Durnez, L.; Phoeuk, P.; Suon, S.; Set, S.; Heng, S.; Siv, S.; Gerrets, R.; Tho, S.; Coosemans, M.; Peeters Grietens, K.

2015-01-01

In Cambodia, despite an impressive decline in prevalence over the last 10 years, malaria is still a public health problem in some parts of the country. This is partly due to vectors that bite early and outdoors reducing the effectiveness of measures such as Long-Lasting Insecticidal Nets. Repellents

Essential oils of medicinal plants from the central andes of Argentina: chemical composition, and antifungal, antibacterial, and insect-repellent activities.

Science.gov (United States)

Lima, Beatriz; López, Sandra; Luna, Lorena; Agüero, María B; Aragón, Liliana; Tapia, Alejandro; Zacchino, Susana; López, María L; Zygadlo, Julio; Feresin, Gabriela E

2011-05-01

The antifungal, antibacterial, and insect-repellent activities of the essential oils (EOs) of Acantholippia seriphioides, Artemisia mendozana, Gymnophyton polycephalum, Satureja parvifolia, Tagetes mendocina, and Lippia integrifolia, collected in the Central Andes area, province of San Juan, Argentina, were investigated. The dermatophytes Microsporum gypseum, Trichophyton mentagrophytes, and T. rubrum were inhibited by the EOs of G. polycephalum, L. integrifolia, and S. parvifolia, with minimum inhibitory concentrations (MICs) between 31.2 and 1000 μg/ml. Moreover, all EOs presented moderate activity against the bacteria tested, and the L. integrifolia and G. polycephalum EOs showed excellent repellent properties against Triatoma infestans, the Chagas disease vector, with repellency values between 60 and 100%. The A. seriphioides, G. polycephalum, and L. integrifolia EOs, obtained by hydrodistillation, were characterized by GC-FID and GC/MS analyses. The highest number of components (40) was identified in L. integrifolia EO, which, along with that of A. seriphioides, contained important amounts of oxygenated monoterpenes (44.35 and 29.72%, resp.). Thymol (27.61%) and carvacrol (13.24%) were the main components of A. seriphioides EO, and borneol, lippifoli-1(6)-en-5-one, and terpinen-4-ol (>8.5%) were the principal compounds of L. integrifolia EO. These results support the idea that oxygenated monoterpenes are the bioactive fractions of the EOs. Finally, the study shows that these Andean species might be used to treat superficial fungal infections and to improve the local Chagas disease situation by vector-control. Copyright © 2011 Verlag Helvetica Chimica Acta AG, Zürich.

Repellent effects of the essential oils of Cymbopogon citratus and Tagetes minuta on the sandfly, Phlebotomus duboscqi.

Science.gov (United States)

Kimutai, Albert; Ngeiywa, Moses; Mulaa, Margaret; Njagi, Peter G N; Ingonga, Johnstone; Nyamwamu, Lydia B; Ombati, Cyprian; Ngumbi, Philip

2017-02-15

The sandfly, Phlebotomus duboscqi is a vector of zoonotic cutaneous leishmaniasis (ZCL) that is an important public health problem in Eastern Africa. Repellents have been used for protection of humans against vectors of ZCL and other vectors that transmit killer diseases including malaria, Rift Valley fever, dengue, and yellow fever. The repellent effects of different doses of the essential oils from the lemon grass, Cymbopogon citratus and Mexican marigold, Tagetes minuta were evaluated in a two-chamber bioassay against 3- to 7-day-old unfed females of P. duboscqi in the laboratory. The results were compared with those that were obtained when test animals were treated with an equivalent dose of diethyl-3-methylbenzamide, which is a repellent that is commonly used as a positive control. Overall, percentage repellency increased with increasing doses of the essential oils while biting rates decreased with increasing concentrations of the oils. Further, the oil of C. citratus was more potent than that of T. minuta with regard to protection time and biting deterrence. The effective doses at 50% (ED 50 ) and at 90% (ED 90 ) for the oil of C. citratus, were 0.04 and 0.79 mg/ml, respectively. Those of the oil of T. minuta were 0.10 and 12.58 mg/ml. In addition, the percentage repellency of 1 mg/ml of the essential oils of C. citratus and T. minuta against sandflies was 100% and 88.89%, respectively. A lower dose of 0.5 mg/ml of the oils, elicited 89.13% repellency for C. citratus and 52.22% for T. minuta. The laboratory tests showed that the essential oils of the two plants were highly repellent to adult sand flies, P. duboscqi. Thus, the two essential oils are candidate natural repellents that can be used against P. duboscqi due to their high efficacy at very low doses, hence, the envisaged safety in their use over chemical repellents. It remains to carry out clinical studies on human subjects with appropriate formulations of the oils prior to recommending their

Bug bites and stings: When to see a dermatologist

Medline Plus

Full Text Available ... your shirt into your pants. You can also pre-treat outer layers of clothing with insect repellent ... against mosquitoes. Look for one that has been pre-treated with pyrethroid insecticide. If it doesn’t ...

Efficacy of Plant-Derived and Synthetic Compounds on Clothing as Repellents Against Ixodes scapularis and Amblyomma americanum (Acari: Ixodidae)

Science.gov (United States)

2012-01-01

efÞcacy of the repellent deet against Aedes aegypti . J. Am. Mosq. Control Assoc. 14: 178Ð182. Robbins, P. J., and M. G. Cherniack. 1986. Review of...number of reported Lyme disease cases reached an all- time high of35,000 in 2008 (CDC 2010). The blacklegged tick, Ixodes scapularis Say, the principal...Paddock 2003, Mixson et al. 2006, Apperson et al. 2008). Repellents remain the primary method of personal protection against tick bites (Piesman and

Bug bites and stings: When to see a dermatologist

Medline Plus

Full Text Available ... are also wearing sunscreen, apply your sunscreen first, let it dry, and then apply the insect repellent. ... notice Copyright © 2018 American Academy of Dermatology. All rights reserved. Reproduction or republication strictly prohibited without prior ...

A preventive immunization approach against insect bite hypersensitivity: Intralymphatic injection with recombinant allergens in Alum or Alum and monophosphoryl lipid A.

Science.gov (United States)

Jonsdottir, Sigridur; Svansson, Vilhjalmur; Stefansdottir, Sara Bjork; Schüpbach, Gertraud; Rhyner, Claudio; Marti, Eliane; Torsteinsdottir, Sigurbjorg

2016-04-01

Insect bite hypersensitivity (IBH) is an IgE-mediated dermatitis of horses caused by bites of Culicoides insects, not indigenous to Iceland. Horses born in Iceland and exported to Culicoides-rich areas are frequently affected with IBH. The aims of the study were to compare immunization with recombinant allergens using the adjuvant aluminum hydroxide (Alum) alone or combined with monophosphoryl lipid A (MPLA) for development of a preventive immunization against IBH. Twelve healthy Icelandic horses were vaccinated intralymphatically three times with 10 μg each of four recombinant Culicoides nubeculosus allergens in Alum or in Alum/MPLA. Injection with allergens in both Alum and Alum/MPLA resulted in significant increase in specific IgG subclasses and IgA against all r-allergens with no significant differences between the adjuvant groups. The induced antibodies from both groups could block binding of allergen specific IgE from IBH affected horses to a similar extent. No IgE-mediated reactions were induced. Allergen-stimulated PBMC from Alum/MPLA horses but not from Alum only horses produced significantly more IFNγ and IL-10 than PBMC from non-vaccinated control horses. In conclusion, intralymphatic administration of small amounts of pure allergens in Alum/MPLA induces high IgG antibody levels and Th1/Treg immune response and is a promising approach for immunoprophylaxis and immunotherapy against IBH. Copyright © 2016 Elsevier B.V. All rights reserved.

To bite or not to bite! A questionnaire-based survey assessing why some people are bitten more than others by midges

Directory of Open Access Journals (Sweden)

Weeks Emma NI

2010-05-01

Full Text Available Abstract Background The Scottish biting midge, Culicoides impunctatus, responsible for more than 90% of biting attacks on human beings in Scotland, is known to demonstrate a preference for certain human hosts over others. Methods In this study we used a questionnaire-based survey to assess the association between people's perception of how badly they get bitten by midges and their demographic, lifestyle and health related characteristics. Results Most people (85.8% reported being bitten sometimes, often or always with only 14.2% reporting never being bitten by midges when in Scotland. There was no association between level of bites received and age, smoking, diet, exercise, medication, eating strongly flavoured foods or alcohol consumption. However, there was a strong association between the probability of being bitten and increasing height (in men and BMI (in women. A large proportion of participants (33.8% reported experiencing a bad/severe reaction to midge bites while 53.1% reported a minor reaction and 13.1% no reaction at all. Also, women tend to react more than men to midge bites. Additionally, the results indicated that the susceptibility to being bitten by midges is hereditary. Conclusions This study suggests that midges prefer to bite men that are tall and women that have a large BMI, and that the tendency for a child to be bitten or not could be inherited from their parent. The study is questionnaire-based; therefore, the interpretation of the results may be limited by the subjectivity of the answers given by the respondents. Although the results are relevant only to the Scottish biting midge, the approach used here could be useful for investigating human-insect interactions for other insects, particularly those which transmit pathogens that cause disease.

Water repellents and water-repellent preservatives for wood

Science.gov (United States)

R. Sam. Williams; William C. Feist

1999-01-01

Water repellents and water-repellent preservatives increase the durability of wood by enabling the wood to repel liquid water. This report focuses on water-repellent finishes for wood exposed outdoors above ground. The report includes a discussion of the effects of outdoor exposure on wood, the characteristics of water repellent and water-repellent preservative...

A low-cost repellent for malaria vectors in the Americas: results of two field trials in Guatemala and Peru.

Science.gov (United States)

Moore, Sarah J; Darling, Samuel T; Sihuincha, Moisés; Padilla, Norma; Devine, Gregor J

2007-08-01

The cost of mosquito repellents in Latin America has discouraged their wider use among the poor. To address this problem, a low-cost repellent was developed that reduces the level of expensive repellent actives by combining them with inexpensive fixatives that appear to slow repellent evaporation. The chosen actives were a mixture of para-menthane-diol (PMD) and lemongrass oil (LG). To test the efficacy of the repellent, field trials were staged in Guatemala and Peru. Repellent efficacy was determined by human-landing catches on volunteers who wore the experimental repellents, control, or 15% DEET. The studies were conducted using a balanced Latin Square design with volunteers, treatments, and locations rotated each night. In Guatemala, collections were performed for two hours, commencing three hours after repellent application. The repellent provided >98% protection for five hours after application, with a biting pressure of >100 landings per person/hour. The 15% DEET control provided lower protection at 92% (p 46 landings per person/hour. The 20% DEET control provided significantly lower protection at 64% (p < 0.0001). In both locations, the PMD/LG repellent provided excellent protection up to six hours after application against a wide range of disease vectors including Anopheles darlingi. The addition of fixatives to the repellent extended its longevity while enhancing efficacy and significantly reducing its cost to malaria-endemic communities.

A low-cost repellent for malaria vectors in the Americas: results of two field trials in Guatemala and Peru

Directory of Open Access Journals (Sweden)

Sihuincha Moisés

2007-08-01

Full Text Available Abstract Background The cost of mosquito repellents in Latin America has discouraged their wider use among the poor. To address this problem, a low-cost repellent was developed that reduces the level of expensive repellent actives by combining them with inexpensive fixatives that appear to slow repellent evaporation. The chosen actives were a mixture of para-menthane-diol (PMD and lemongrass oil (LG. Methods To test the efficacy of the repellent, field trials were staged in Guatemala and Peru. Repellent efficacy was determined by human-landing catches on volunteers who wore the experimental repellents, control, or 15% DEET. The studies were conducted using a balanced Latin Square design with volunteers, treatments, and locations rotated each night. Results In Guatemala, collections were performed for two hours, commencing three hours after repellent application. The repellent provided >98% protection for five hours after application, with a biting pressure of >100 landings per person/hour. The 15% DEET control provided lower protection at 92% (p 46 landings per person/hour. The 20% DEET control provided significantly lower protection at 64% (p Conclusion In both locations, the PMD/LG repellent provided excellent protection up to six hours after application against a wide range of disease vectors including Anopheles darlingi. The addition of fixatives to the repellent extended its longevity while enhancing efficacy and significantly reducing its cost to malaria-endemic communities.

Insecticidal, acaricidal and repellent effects of DEET- and IR3535-impregnated bed nets using a novel long-lasting polymer-coating technique.

Science.gov (United States)

Faulde, Michael K; Albiez, Gunther; Nehring, Oliver

2010-03-01

A novel long-lasting repellent-treated net (LLRTN) has been designed by binding the skin repellents N,N-diethyl-m-toluamide (DEET), or IR3535, onto the fibres of bed net fabric using a new polymer-coating technique. The repellent toxicological effectiveness and residual activity of a factory-based repellent-impregnated fabric has been evaluated by laboratory testing against adult Aedes aegypti mosquitoes and nymphal Ixodes ricinus ticks. By using this repellent-embedding impregnation technique, concentrations exceeding 10 g/m(2) could be achieved with one single polymer layer. Both DEET- and IR3535-impregnated fabrics revealed a dose-dependent insecticidal as well as acaricidal activity. One hundred percent knockdown times of DEET-treated bed nets ranged from 187.5 +/- 31.8 to 27.5 +/- 3.5 min against A. aegypti, and between 214 +/- 47 and 22.6 +/- 5 min against nymphal I. ricinus, linked to a DEET concentration of 1.08 and 10.58 g/m(2), respectively. With IR3535, A. aegypti produced dose-dependent 100% knockdown times varying from 87.5 +/- 10.6 to 57.5 +/- 3.5 min and between 131.4 +/- 6.5 and 33.8 +/- 5 min against nymphal I. ricinus, respectively, linked to concentrations between 1.59 and 10.02 g/m(2). One hundred percent repellency measured by complete landing and biting protection of impregnated fabric by using the arm-in-cage test could be achieved at DEET concentrations exceeding 3.7 to 3.9 g/m(2), and for IR3535 concentrations over 10 g/m(2). One hundred percent landing and biting protection could be preserved with DEET-treated fabrics for 29 weeks at an initial concentration of 4.66 g/m(2), 54 weeks at 8.8 g/m(2), 58 weeks at 9.96 g/m(2) and 61 weeks at 10.48 g/m(2) for DEET, and 23 weeks for IR3535-treated fabric at a concentration of 10.02 g/m(2). Unlike repellent-treated fabric, a brand of a commercially available long-lasting insecticide-treated net tested containing 500 mg permethrin/m(2) did not protect from mosquito bites. First results on

Insect Bites and Stings: First Aid

Science.gov (United States)

... Tips to remember. American Academy of Allergy, Asthma & Immunology. http://www.aaaai.org/conditions-and-treatments/library/allergy-library/stinging-insect-allergy.aspx. Accessed Jan. 9, 2018. LoVecchio F. ...

Protection against mosquito vectors Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus using a novel insect repellent, ethyl anthranilate.

Science.gov (United States)

Islam, Johirul; Zaman, Kamaruz; Tyagi, Varun; Duarah, Sanjukta; Dhiman, Sunil; Chattopadhyay, Pronobesh

2017-10-01

Growing concern on the application of synthetic mosquito repellents in the recent years has instigated the identification and development of better alternatives to control different mosquito-borne diseases. In view of above, present investigation evaluates the repellent activity of ethyl anthranilate (EA), a non-toxic, FDA approved volatile food additive against three known mosquito vectors namely, Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus under laboratory conditions following standard protocols. Three concentration levels (2%, 5% and 10% w/v) of EA were tested against all the three selected mosquito species employing K & D module and arm-in-cage method to determine the effective dose (ED 50 ) and complete protection time (CPT), respectively. The repellent activity of EA was further investigated by modified arm-in-cage method to determine the protection over extended spatial ranges against all mosquito species. All behavioural situations were compared with the well-documented repellent N,N-diethylphenyl acetamide (DEPA) as a positive control. The findings demonstrated that EA exhibited significant repellent activity against all the three mosquitoes species. The ED 50 values of EA, against Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus were found to be 0.96%, 5.4% and 3.6% w/v, respectively. At the concentration of 10% w/v, it provided CPTs of 60, 60 and 30min, respectively, against Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus mosquitoes. Again in spatial repellency evaluation, EA was found to be extremely effective in repelling all the three tested species of mosquitoes. Ethyl anthranilate provided comparable results to standard repellent DEPA during the study. Results have concluded that the currently evaluated chemical, EA has potential repellent activity against some well established mosquito vectors. The study emphasizes that repellent activity of EA could be exploited for developing effective, eco

Zein Nanoparticles as Eco-Friendly Carrier Systems for Botanical Repellents Aiming Sustainable Agriculture.

Science.gov (United States)

Oliveira, Jhones L de; Campos, Estefânia V R; Pereira, Anderson E S; Pasquoto, Tatiane; Lima, Renata; Grillo, Renato; Andrade, Daniel Junior de; Santos, Fabiano Aparecido Dos; Fraceto, Leonardo Fernandes

2018-02-14

Botanical repellents represent one of the main ways of reducing the use of synthetic pesticides and the contamination of soil and hydric resources. However, the poor stability and rapid degradation of these compounds in the environment hinder their effective application in the field. Zein nanoparticles can be used as eco-friendly carrier systems to protect these substances against premature degradation, provide desirable release characteristics, and reduce toxicity in the environment and to humans. In this study, we describe the preparation and characterization of zein nanoparticles loaded with the main constituents of the essential oil of citronella (geraniol and R-citronellal). The phytotoxicity, cytotoxicity, and insect activity of the nanoparticles toward target and nontarget organisms were also evaluated. The botanical formulations showed high encapsulation efficiency (>90%) in the nanoparticles, good physicochemical stability, and effective protection of the repellents against UV degradation. Cytotoxicity and phytotoxicity assays showed that encapsulation of the botanical repellents decreased their toxicity. Repellent activity tests showed that nanoparticles containing the botanical repellents were highly repellent against the Tetranychus urticae Koch mite. This nanotechnological formulation offers a new option for the effective use of botanical repellents in agriculture, reducing toxicity, protecting against premature degradation, and providing effective pest control.

Increasing Insect Reactions in Alaska: Is this Related to Changing Climate?

OpenAIRE

Jeffrey Demain; Bradford Gessner; Joseph McLaughlin; Derek Sikes; Timothy Foote

2008-01-01

During the summer of 2006, Fairbanks Alaska experienced its first two known cases of fatal anaphylaxis as a result of Hymenoptera stings, presumably from yellowjackets. An increase in insect bites and stings has been observed throughout the state.Has there been an increased incidence of medical visits due to insect bites and stings in Alaska in recent years? We conducted a retrospective review of three independent patient databases in Alaska to identify trends of patients seeking medical care...

[Adverse reactions to mosquito bites in scholars from Monterrey, Nuevo Leon, Mexico].

Science.gov (United States)

Manrique López, María Amelia; González Díaz, Sandra N; Arias Cruz, Alfredo; Sedó Mejía, Giovanni A; Canseco Villarreal, José Ignacio; Gómez Retamoza, Ernesto Antonio; Padrón López, Olga Magdalena; Cruz Moreno, Miguel Angel; Cisneros Salazar, Guillermo Daniel

2010-01-01

Allergic reactions to insect bites are a global problem, the true incidence and prevalence of morbidity from adverse reactions to mosquito bites are unknown. To describe the adverse reactions to mosquito bites in school-age children of Monterrey, Nuevo Leon. A cross-sectional descriptive study was made via a randomized application of questionnaires to children from public elementary schools in the metropolitan area of Monterrey, Nuevo Leon. A total of 11 public schools randomly selected were included in the study. One thousand questionnaires were submitted, of which 506 fulfilled the inclusion criteria; 55% were females. Seventy-six percent referred adverse reactions to mosquito bites, itching (75%) and rash (72%) being the most frequent ones, in the last 12 months. Adverse reactions to mosquito bites occur frequently. Early detection is important to establish a prompt treatment.

Repellent Action of Carapa guianensis and Caesalpinia ferrea for flies species of Calliphoridae family

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Ciciane Pereira Marten Fernandes

2016-05-01

Full Text Available ABSTRACT: Myiases occur by the infestation of fly larvae in tissues of live vertebrate animals, resulting in economic loss. Phytotherapy is considered an important alternative in the control of insects, which may reduce the economic impacts . Carapa guianensis is a plant that has been studied as a repellent against mosquitoes and Caesalpinia ferrea is reported in tropical climates, and there are few studies about its repellent action. The present study was designed to evaluate the repellent action of s C. guianensis and C. ferrea plants on flies species of the Calliphoridae family. W.O.T. traps containing deteriorated bovine liver and herbs cream of at concentrations of 20 and 50% were used to catch the flies. It was reported that the creams containing C. ferrea at concentrations of 20 and 50% and C. guianensis at the concentration of 50% have repellent effect against species of Calliphoridae family.

Efficacy of plant-derived and synthetic compounds on clothing as repellents against Ixodes scapularis and Amblyomma americanum (Acari: Ixodidae).

Science.gov (United States)

Jordan, Robert A; Schulze, Terry L; Dolan, Marc C

2012-01-01

We conducted field trials to compare the relative repellent activity of two natural product compounds (nootkatone and carvacrol) with commercially available plant-derived (EcoSMART organic insect repellent) and permethrin-based (Repel Permanone) repellents against adult Ixodes scapularis Say and Amblyomma americanum (L.) (Acari: Ixodidae) by using treated coveralls. One day after treatment, nootkatone and carvacrol provided 100% repellency of I. scapularis adults, with nootkatone maintaining complete protection through 3 d, whereas carvacrol showed steadily declining repellency against I. scapularis during the 7-d course of the trials. Nootkatone was at least as effective against host-seeking A. americanum as against I. scapularis through 3 d. Carvacrol provided little protection against A. americanum adults. Both natural compounds performed well initially in comparison with the commercial products. After 7 d, nootkatone was the most effective against both species followed in order of activity by Permanone, EcoSMART, and carvacrol. Nootkatone seems to have offer considerable potential as a clothing repellent against both I. scapularis and A. americanum.

Chemical Composition and Repellent Activity of Achillea vermiculata and Satureja hortensis against Anopheles stephensi

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Masoumeh Pirmohammadi

2016-01-01

Full Text Available Background: One of the best ways to control the malaria disease and to be protected human against Anopheles mos­quito biting is the use of repellents. Throughout repellents, herbal ones may be an appropriate and safe source for protection.Methods: Chemical constituents of Achillea vermiculata and Satoreja hortensis were determined by using gas chromatography-mass spectrometry. Efficacy and the protection time of these plants were assessed on Anopheles stephensi under the laboratory condition.Results: The mean assessed protection time and efficacy for A. vermiculata was 2.16 and 3.16 hours respectively and the obtained ED50 and ED90 for this plant was 5.67 and 63 µl/cm2 respectively. The figured for S. hortensis was 4.16 and 5 hours respectively.  ED50 and ED90 for this plant were 5.63 and 45.75µl/cm2 respectively.Conclusion: Results of investigation showed that S. hortensis plant has an acceptable protection time, therefore, this plant could be considered as a good herbal repellent against anopheles mosquitoes.

Chemosensory responses to the repellent nepeta essential oil and its major component nepetalactone by the yellow fever mosquito, aedes aegypti, a vector of zika virus

Science.gov (United States)

Nepeta essential oil (Neo) (catnip) and its major component, nepetalactone, have long been known to repel insects including mosquitoes. However, the neural mechanisms through which these repellents are detected by mosquitoes, including the yellow fever mosquito Aedes aegypti, an important vector of...

Efficacy of Some Wearable Devices Compared with Spray-On Insect Repellents for the Yellow Fever Mosquito, Aedes aegypti (L.) (Diptera: Culicidae).

Science.gov (United States)

Rodriguez, Stacy D; Chung, Hae-Na; Gonzales, Kristina K; Vulcan, Julia; Li, Yiyi; Ahumada, Jorge A; Romero, Hector M; De La Torre, Mario; Shu, Fangjun; Hansen, Immo A

2017-01-01

The current Zika health crisis in the Americas has created an intense interest in mosquito control methods and products. Mosquito vectors of Zika are of the genus Aedes, mainly the yellow fever mosquito, Aedes aegypti. L. The use of repellents to alter mosquito host seeking behavior is an effective method for the prevention of mosquito-borne diseases. A large number of different spray-on repellents and wearable repellent devices are commercially available. The efficacies of many repellents are unknown. This study focuses on the efficacy of eleven different repellents in reducing the number of Ae. aegypti female mosquitoes attracted to human bait. We performed attraction-inhibition assays using a taxis cage in a wind tunnel setting. One person was placed upwind of the taxis cage and the mosquito movement towards or away from the person was recorded. The person was treated with various spray-on repellents or equipped with different mosquito repellent devices. We found that the spray-on repellents containing N,N-Diethyl-meta-toluamide and p-menthane-3,8-diol had the highest efficacy in repelling mosquitoes compared to repellents with other ingredients. From the five wearable devices that we tested, only the one that releases Metofluthrin significantly reduced the numbers of attracted mosquitoes. The citronella candle had no effect. We conclude that many of the products that we tested that were marketed as repellents do not reduce mosquito attraction to humans. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.

Diaphorina citri Induces Huanglongbing-Infected Citrus Plant Volatiles to Repel and Reduce the Performance of Propylaea japonica.

Science.gov (United States)

Lin, Yongwen; Lin, Sheng; Akutse, Komivi S; Hussain, Mubasher; Wang, Liande

2016-01-01

Transmission of plant pathogens through insect vectors is a complex biological process involving interactions between the host plants, insects, and pathogens. Simultaneous impact of the insect damage and pathogenic bacteria in infected host plants induce volatiles that modify not only the behavior of its insect vector but also of their natural enemies, such as parasitoid wasps. Therefore, it is essential to understand how insects such as the predator ladybird beetle responds to volatiles emitted from a host plant and how the disease transmission alters the interactions between predators, vector, pathogens, and plants. In this study, we investigated the response of Propylaea japonica to volatiles from citrus plants damaged by Diaphorina citri and Candidatus Liberibacter asiaticus through olfactometer bioassays. Synthetic chemical blends were also used to determine the active compounds in the plant volatile. The results showed that volatiles emitted by healthy plants attracted more P. japonica than other treatments, due to the presence of high quantities of D-limonene and beta-ocimene, and the lack of methyl salicylate. When using synthetic chemicals in the olfactory tests, we found that D-limonene attracted P. japonica while methyl salicylate repelled the predator. However, beta-ocimene attracted the insects at lower concentrations but repelled them at higher concentrations. These results indicate that P. japonica could not efficiently search for its host by using volatile cues emitted from psyllids- and Las bacteria-infected citrus plants.

Insecticidal and insect-repellent activities of essential oils from Verbenaceae and Anacardiaceae against Rhizopertha dominica.

Science.gov (United States)

Benzi, Verónica S; Murrayb, Ana P; Ferrero, Adriana A

2009-09-01

Essential oils extracted from leaves of Aloysia polystachya and A. citriodora (Verbenaceae) and from leaves and fruits of Schinus molle var. areira (Anacardiaceae) were tested for their repellent and toxic activities against adults of Rhizopertha dominica (Coleoptera: Bostrichidae). Topical application and filter paper assays were employed for contact toxicity studies; filter paper impregnation was also used for fumigant and repellent assays. In topical tests A. polystachya was as effective as S. molle leaves. In the case of repellent assays, A. citriodora was the most effective oil based on the class scale. A. polystachya was the most toxic plant on contact toxicity by filter paper assay (LC50 26.6 mg/cm2). Fumigant toxicity was only evaluated with fruits and leaves of S. molle, and no significant differences were found between them. Published data are included to compare the fumigant toxicity of S. molle with that of A. citridora and A. polystachya.

Repellent activity of the creams formulated from Annona senegalensis and Boswellia dalzielii leaf fractions and essential oils against Anopheles gambiae (Diptera: Culicidae

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Lame Younoussa

2016-12-01

Full Text Available Objective: To investigate the repellent efficacy of the creams formulated from methanol extract and n-hexane, chloroform, ethyl acetate and methanol fractions as well as essential oils of Annona senegalensis (A. senegalensis and Boswellia dalzielii (B. dalzielii leaves against the malarial vector Anopheles gambiae (An. gambiae in the laboratory. Methods: The efficacies of 25% w/w active ingredient creams formulated from the plant-based products were tested. Different concentrations of the creams, ranging from 2.0 to 12.0 mg/ cm²were applied on the exposed dorsal hand area (25 cm2 of volunteers. The treated hands were submitted to 50 caged blood-starved females of An. gambiae for 3 min after every 30 min until 180 min. Results: Total protection of up to 120 and 60 min without bites of An. gambiae were recorded with n-hexane creams applied at 12 mg/cm2 respectively for A. senegalensis and B. dalzielii. The essential oil creams of the two tested plants applied at 6 mg/cm2 protected volunteers up to 120 min without mosquito bites. The commercial Odomos cream (12% N,N-diethyl- 3-methylbenzamide tested as the positive control at 6 mg/cm2 protected volunteers from mosquito bites up to180 min. Conclusions: These results suggest that the cream formulated from the n-hexane fraction of A. senegalensis and essential oil creams of A. senegalensis and B. dalzielii leaves have the potential of a natural herbal source for the development of new, safe and eco-friendly repellent products to prevent An. gambiae bites.

Repellent and Fumigant Activities of Tanacetum nubigenum Wallich. ex DC Essential Oils against Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae).

Science.gov (United States)

Haider, S Zafar; Mohan, Manindra; Pandey, Abhay K; Singh, Pooja

2015-01-01

The repellent and fumigant toxicity of essential oils of Tanacetum nubigenum Wallich. ex DC collected from three different habitats (Gothing, Burphu and Glacier) of Uttarakhand Himalayas, India named as TNG, TNB and TNM respectively, were investigated against the adults of red flour beetle Tribolium castaneum (Herbst). Among the three samples tested, TNG was found to more potent exhibiting more repellent effect towards the insects and with LC50 values by fumigant bioassay were 13.23 and 8.32 µl per 0.25 L air at 24 and 48 h exposure of insects to the essential oil respectively. In between other two oil samples, TNM was superior in potency showed LC50 value of 14.22 (24 h) & 8.82 µl per 0.25 L air (48 h). During in vivo study all the essential oil samples significantly protected 500 g of wheat grains for 6 months from insect infestation as compared to non fumigated grains and order of efficacy was TNG>TNM>TNB. There were no side effects of essential oils on germination rate of grains (essential oil of T. nubigenum can be explored as novel natural fumigants for the control of stored product insects.

Review of sangre de drago (Croton lechleri)--a South American tree sap in the treatment of diarrhea, inflammation, insect bites, viral infections, and wounds: traditional uses to clinical research.

Science.gov (United States)

Jones, Kenneth

2003-12-01

The objective of this review is to provide an overview of the pharmacologic evidence that may or may not support clinical and ethnomedical uses of the sap of sangre de drago (dragon's blood; Croton lechleri Müll. Arg.). Data sources used were BIOSIS, EMBASE, PubMed, TOXLIT, International Pharmaceutical Abstracts, manual searches, papers on file from peer-reviewed journals, textbooks available at Armana Research, Inc., and researchers in the field of South American botanical medicine. The results of in vitro and in vivo studies largely support the majority of ethnomedical uses of sangre de drago including the treatment of diarrhea, wounds, tumors, stomach ulcers, herpes infection, the itching, pain and swelling of insect bites, and other conditions. Clinical studies of sangre de drago products have reported positive results in the treatment of traveler's and watery diarrhea and the symptoms of insect bites. Because the sap has shown low toxicity and preparations used in clinical studies were well tolerated, further clinical and pharmacologic studies are anticipated. Acknowledgment of the diversity in the chemical makeup of the sap from one geographic area to another and the recent characterization of alkaloid chemotypes of sangre de drago will require that materials developed for clinical use are standardized.

Culicoides (Diptera: Ceratopogonidae) host preferences and biting rates in the Netherlands : comparing cattle, sheep and the black-light suction trap

NARCIS (Netherlands)

Elbers, A.R.W.; Meiswinkel, R.

2014-01-01

Host preference is an important determinant of feeding behaviour in biting insects and a critical component in the transmission of vector-borne diseases. The aim of the study was to quantify Culicoides (Diptera: Ceratopogonidae) host preferences and biting rates using tethered livestock at pasture

CD4+CD25+ T cells expressing FoxP3 in Icelandic horses affected with insect bite hypersensitivity.

Science.gov (United States)

Hamza, Eman; Steinbach, Falko; Marti, Eliane

2012-07-15

Insect bite hypersensitivity (IBH) is an IgE-mediated dermatitis caused by bites of midges from the genus Culicoides. We have shown previously that peripheral blood mononuclear cells (PBMC) from IBH-affected horses produce higher levels of IL-4 and lower levels of IL-10 and TGF-β1 than those from healthy horses, suggesting that IBH is associated with a reduced regulatory immune response. FoxP3 is a crucial marker of regulatory T cells (Tregs). Here we have determined the proportion of CD4(+)CD25(+)FoxP3(+) T cells by flow cytometry in PBMC directly after isolation or after stimulation with Culicoides extract or a control antigen (Tetanus Toxoid). There were no differences between healthy and IBH horses either in the proportion of FoxP3(+)CD4(+)CD25(+) cells in freshly isolated PBMC or in the following stimulation with Tetanus Toxoid. However, upon stimulation of PBMC with the allergen, expression of FoxP3 by CD4(+)CD25(+high) and CD4(+)CD25(+dim) cells was significantly higher in healthy than in IBH horses. Addition of recombinant IL-4 to PBMC from healthy horses stimulated with the allergen significantly decreased the proportion of FoxP3 expressing cells within CD4(+)CD25(+high). These results suggest that IBH is associated with a decreased number of allergen-induced Tregs. This could be a consequence of the increased IL-4 production by PBMC of IBH-affected horses. Copyright © 2011 Elsevier B.V. All rights reserved.

Chemical Composition and Bioactivity of Essential Oil of Atalantia guillauminii against Three Species Stored Product Insects.

Science.gov (United States)

Yang, Kai; You, Chun-Xue; Wang, Cheng-Fang; Lei, Ning; Guo, Shan-Shan; Geng, Zhu-Feng; Du, Shu-Shan; Ma, Ping; Deng, Zhi-Wei

2015-01-01

The toxic and repellent activities of the essential oil extracted from the leaves of Atalantia guillauminii Swingle were evaluated against three stored product insects, red flour beetles (Tribolium castaneum), cigarette beetles (Lasioderma serricorne) and booklice (Liposcelis bostrychophila). The essential oil obtained by hydrodistillation was investigated by GC-MS. The main constituents of the essential oil were β-thujene (27.18%), elemicin (15.03%), eudesma-3, 7(11)-diene (9.64%), followed by (-)-4-terpeniol (6.70%) and spathulenol (5.25%). The crude oil showed remarkable contact toxicity against T. castaneum, L. serricorne adults and L. bostrychophila with LD50 values of 17.11, 24.07 µg/adult and 55.83 µg/cm(2) respectively and it also displayed strong fumigant toxicity against T. castaneum, L. serricorne adults with LC50 values of 17.60 and 12.06 mg/L respectively, while weak fumigant toxicity against L. bostrychophila with a LC50 value of 16.75 mg/L. Moreover, the essential oil also exhibited the same level repellency against the three stored product insects, relative to the positive control, DEET. At the same concentrations, the essential oil was more repellent to T. castaneum than to L. serricorne. Thus, the essential oil of A. guillauminii may be potential to be developed as a new natural fumigant/repellent in the control of stored product insects.

Efficacy of Advanced Odomos repellent cream (N, N-diethyl-benzamide) against mosquito vectors.

Science.gov (United States)

Mittal, P K; Sreehari, U; Razdan, R K; Dash, A P; Ansari, M A

2011-04-01

Repellents are commonly used personal protection measures to avoid mosquito bites. In the present study, Advanced Odomos cream (12% N, N-diethyl-benzamide) was tested for its efficacy against mosquitoes in comparison to DEET (N,N-diethyl-3-methyl benzamide). Bioassays were conducted to assess the repellency of Advanced Odomos and DEET creams against Anopheles stephensi and Aedes aegypti. Their efficacy was tested on human volunteers applied with different concentrations of test creams ranging from 1 to 12 mg/cm 2 and by exposing them to mosquitoes at hourly intervals. Field evaluation was also carried out to test the duration of protection of the test creams against Anopheles and Aedes mosquitoes during whole night and day time collections, respectively on human volunteers. Mosquito collections were done using torch light and aspirator. Complete (100%) protection was achieved at 10 mg/cm 2 cream formulation of Advanced Odomos (1.2 mg a.i/cm 2 ) dose against An. stephensi and 12 mg/cm 2 (1.44 mg a.i./cm 2 ) against Ae. aegypti on human baits. There was no statistically significant differences in per cent protection against mosquito bites between Advanced Odomos and DEET cream (P>0.05) in respective doses. Complete protection up to 11 h was observed against Anopheles mosquitoes during whole night collections and up to 6 h against Ae. aegypti in day time collections. No adverse reactions such as itching, irritation, vomiting, nausea, etc. were reported by the volunteers. Advanced Odomos cream applied at 10 mg/cm 2 concentration provided 100% protection from Anopheles mosquitoes up to 11 h whereas about 6 h protection was recorded against Ae. aegypti. The laboratory and field trials indicate that for longer protection against Anopheles mosquitoes 10 mg/cm 2 will be appropriate and in case of Ae. aegypti more than 10 mg/cm 2 application is required for complete protection. In conclusion, the Advanced Odomos cream was comparable to the known repellent cream DEET for

Repels

International Nuclear Information System (INIS)

Maki, M.; Clarke, D.; McKeen, W.

1991-01-01

This paper reports on repels (Rapidly Extendible Perimeter Line Sensor) which is a recent development in transportable security technology. Repels utilizes a new coupled wave device technology (CWD) to provide the detection advantages of radio-frequency leaky cable guided radar for portable sensors. These advantages include an invisible, terrain-following detection zone, and an optimal detection characteristic for human-size targets. Repels adds the dimension of portability and set-up of an adjustable zone up to 100 m by a single person, typically within 20 minutes. Internal replaceable D-cell flashlight batteries provide power for weeks of operation. First introduced as a prototype for test and evaluation in 1988, Repels was launched as a Senstar NDI product in 1990. This paper outlines the technical principles of the Repels sensor, recent improvements from the original prototype results of early field test experience on production models, and applications. Recent advances driven by initial field tests include, for example, the use of inductively-coupled transmitter and receiver couplers, so that no radio frequency field connections are required, and simple conductors can be employed. Test and application experience in several countries has expanded from parked aircraft perimeters, military encampments, forward area surveillance, and waterside security, to dignitary protection and failed sensor stand-in. Such sensors may be used to protect facilities dealing with nuclear materials

Toxicity and repellence of African plants traditionally used for the protection of stored cowpea against Callosobruchus maculatus

NARCIS (Netherlands)

Boeke, S.J.; Baumgart, I.R.; Loon, van J.J.A.; Huis, van A.; Dicke, M.; Kossou, D.K.

2004-01-01

In a search for botanical products to control the main insect pest of stored cowpea, Callosobruchus maculatus, 33 traditionally used African plants were tested in the laboratory for their toxic and repellent effects against this beetle. Toxicity was evaluated measuring life history parameters in a

Protection against Mycobacterium ulcerans lesion development by exposure to aquatic insect saliva.

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Laurent Marsollier

2007-02-01

Full Text Available BACKGROUND: Buruli ulcer is a severe human skin disease caused by Mycobacterium ulcerans. This disease is primarily diagnosed in West Africa with increasing incidence. Antimycobacterial drug therapy is relatively effective during the preulcerative stage of the disease, but surgical excision of lesions with skin grafting is often the ultimate treatment. The mode of transmission of this Mycobacterium species remains a matter of debate, and relevant interventions to prevent this disease lack (i the proper understanding of the M. ulcerans life history traits in its natural aquatic ecosystem and (ii immune signatures that could be correlates of protection. We previously set up a laboratory ecosystem with predatory aquatic insects of the family Naucoridae and laboratory mice and showed that (i M. ulcerans-carrying aquatic insects can transmit the mycobacterium through bites and (ii that their salivary glands are the only tissues hosting replicative M. ulcerans. Further investigation in natural settings revealed that 5%-10% of these aquatic insects captured in endemic areas have M. ulcerans-loaded salivary glands. In search of novel epidemiological features we noticed that individuals working close to aquatic environments inhabited by insect predators were less prone to developing Buruli ulcers than their relatives. Thus we set out to investigate whether those individuals might display any immune signatures of exposure to M. ulcerans-free insect predator bites, and whether those could correlate with protection. METHODS AND FINDINGS: We took a two-pronged approach in this study, first investigating whether the insect bites are protective in a mouse model, and subsequently looking for possibly protective immune signatures in humans. We found that, in contrast to control BALB/c mice, BALB/c mice exposed to Naucoris aquatic insect bites or sensitized to Naucoris salivary gland homogenates (SGHs displayed no lesion at the site of inoculation of M. ulcerans

Protection against Mycobacterium ulcerans lesion development by exposure to aquatic insect saliva.

Science.gov (United States)

Marsollier, Laurent; Deniaux, Estelle; Brodin, Priscille; Marot, Agnès; Wondje, Christelle Mbondji; Saint-André, Jean-Paul; Chauty, Annick; Johnson, Christian; Tekaia, Fredj; Yeramian, Edouard; Legras, Pierre; Carbonnelle, Bernard; Reysset, Gilles; Eyangoh, Sara; Milon, Geneviève; Cole, Stewart T; Aubry, Jacques

2007-02-01

Buruli ulcer is a severe human skin disease caused by Mycobacterium ulcerans. This disease is primarily diagnosed in West Africa with increasing incidence. Antimycobacterial drug therapy is relatively effective during the preulcerative stage of the disease, but surgical excision of lesions with skin grafting is often the ultimate treatment. The mode of transmission of this Mycobacterium species remains a matter of debate, and relevant interventions to prevent this disease lack (i) the proper understanding of the M. ulcerans life history traits in its natural aquatic ecosystem and (ii) immune signatures that could be correlates of protection. We previously set up a laboratory ecosystem with predatory aquatic insects of the family Naucoridae and laboratory mice and showed that (i) M. ulcerans-carrying aquatic insects can transmit the mycobacterium through bites and (ii) that their salivary glands are the only tissues hosting replicative M. ulcerans. Further investigation in natural settings revealed that 5%-10% of these aquatic insects captured in endemic areas have M. ulcerans-loaded salivary glands. In search of novel epidemiological features we noticed that individuals working close to aquatic environments inhabited by insect predators were less prone to developing Buruli ulcers than their relatives. Thus we set out to investigate whether those individuals might display any immune signatures of exposure to M. ulcerans-free insect predator bites, and whether those could correlate with protection. We took a two-pronged approach in this study, first investigating whether the insect bites are protective in a mouse model, and subsequently looking for possibly protective immune signatures in humans. We found that, in contrast to control BALB/c mice, BALB/c mice exposed to Naucoris aquatic insect bites or sensitized to Naucoris salivary gland homogenates (SGHs) displayed no lesion at the site of inoculation of M. ulcerans coated with Naucoris SGH components. Then using

Deltamethrin-resistant German Cockroaches Are Less Sensitive to the Insect Repellents DEET and IR3535 than Non-resistant Individuals.

Science.gov (United States)

Mengoni, Sofía L; Alzogaray, Raúl A

2018-04-02

The German cockroach, Blattella germanica (L.) (Blattodea: Blattellidae), is a serious worldwide pest with a considerable economical and sanitary impact. It is mainly controlled by the application of synthetic insecticides, but repeated use of these substances has promoted the appearance of resistance in cockroach populations throughout the world. The aim of this study was to compare the behavior of deltamethrin-susceptible (CIPEIN colony) and deltamethrin-resistant (JUBA and VGBA colonies) first instar nymphs exposed to the repellents N,N-diethyl-3-methylbenzamide (DEET) and ethyl 3-[acetyl(butyl)amino]propanoate (IR3535). Firstly, the behavior of the nymphs was assessed in an experimental arena in the absence of repellents. The parameters Distance Traveled, Velocity, Mobility Time, and Time Spent (in each half of the arena) were quantified using an image analyser, and showed that the behavior elicited by the three colonies was similar. After this, the behavior of the nymphs was quantified in an arena, half of which had been treated with repellent. The repellency of DEET increased as a linear function of log concentration for the three colonies. DEET elicited repellency as from a concentration of 97.49 µg/cm2 for the CIPEIN and JUBA colonies and 194.98 µg/cm2 for the VGBA colony. The repellency of IR3535 was weaker and started at a concentration of 389.96 µg/cm2 for the CIPEIN colony, 779.92 μg/cm2 for JUBA, and 1559.84 μg/cm2 for VGBA . Finally, nymphs were exposed to 3:1, 1:1, and 1:3 DEET:IR3535 mixtures, and a synergistic effect was observed only in the CIPEIN colony.

A new approach to quantify semiochemical effects on insects based on energy landscapes.

Directory of Open Access Journals (Sweden)

Rory P Wilson

Full Text Available Our ability to document insect preference for semiochemicals is pivotal in pest control as these agents can improve monitoring and be deployed within integrated pest management programmes for more efficacious control of pest species. However, methods used to date have drawbacks that limit their utility. We present and test a new concept for determining insect motivation to move towards, or away from, semiochemicals by noting direction and speed of movement as animals work against a defined energy landscape (environmentally dependent variation in the cost of transport requiring different powers to negotiate. We conducted trials with the pine weevils Hylobius abietis and peach-potato aphids Myzus persicae exposed to various attractants and repellents and placed so that they either moved up defined slopes against gravity or had to travel over variously rough surfaces.Linear Mixed Models demonstrated clear reductions in travel speed by insects moving along increasingly energetically taxing energy landscapes but also that responses varied according to different semiochemicals, thus highlighting the value of energy landscapes as a new concept to help measure insect motivation to access or avoid different attractants or repellents across individuals.New sensitive, detailed indicators of insect motivation derived from this approach should prove important in pest control across the world.

Treating insect-bite hypersensitivity in horses with active vaccination against IL-5.

Science.gov (United States)

Fettelschoss-Gabriel, Antonia; Fettelschoss, Victoria; Thoms, Franziska; Giese, Christoph; Daniel, Michelle; Olomski, Florian; Kamarachev, Jivko; Birkmann, Katharina; Bühler, Maya; Kummer, Martin; Zeltins, Andris; Marti, Eliane; Kündig, Thomas M; Bachmann, Martin F

2018-03-28

Insect-bite hypersensitivity is the most common allergic dermatitis in horses. Excoriated skin lesions are typical symptoms of this seasonal and refractory chronic disease. On a cellular level, the skin lesions are characterized by massive eosinophil infiltration caused by an underlying allergic response. To target these cells and treat disease, we developed a therapeutic vaccine against equine IL-5 (eIL-5), the master regulator of eosinophils. The vaccine consisted of eIL-5 covalently linked to a virus-like particle derived from cucumber mosaic virus containing the tetanus toxoid universal T-cell epitope tt830-843 (CMV TT ). Thirty-four Icelandic horses were recruited and immunized with 400 μg of eIL-5-CMV TT formulated in PBS without adjuvant (19 horses) or PBS alone (15 horses). The vaccine was well tolerated and did not reveal any safety concerns but was able to induce anti-eIL-5 autoantibody titers in 17 of 19 horses. This resulted in a statistically significant reduction in clinical lesion scores when compared with previous season levels, as well as levels in placebo-treated horses. Protection required a minimal threshold of anti-eIL-5 antibodies. Clinical improvement by disease scoring showed that 47% and 21% of vaccinated horses reached 50% and 75% improvement, respectively. In the placebo group no horse reached 75% improvement, and only 13% reached 50% improvement. Our therapeutic vaccine inducing autoantibodies against self IL-5 brings biologics to horses, is the first successful immunotherapeutic approach targeting a chronic disease in horses, and might facilitate development of a similar vaccine against IL-5 in human subjects. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Repellency and toxicity of aromatic plant extracts against the mosquito Culex pipiens molestus (Diptera: Culicidae).

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Traboulsi, Abdallah F; El-Haj, Samih; Tueni, Marie; Taoubi, Khalil; Nader, Natalie Abi; Mrad, Abir

2005-06-01

The insecticidal activities of essential oil extracts from leaves, flowers and roots of aromatic plants against fourth-instar larvae of the mosquito Culex pipiens molestus Forskal were determined. Extracts of Foeniculum vulgare Mill were the most toxic, followed by those of Ferula hermonis Boiss, Citrus sinensis Osbeck, Pinus pinea L, Laurus nobilis L and Eucalyptus spp with LC50 values of 24.5, 44.0, 60.0, 75.0, 117.0 and 120.0 mg litre(-1), respectively. Combination tests between the LC50 and the maximum sub-lethal concentration (MSLC) were determined. Over 20 major components were identified in extracts from each plant species tested. Five essential oils and nine pure components were studied for their repellency against mosquito bites. Terpineol and 1,8-cineole were the most effective against Culex pipiens molestus bites offering complete protection for 1.6 and 2 h, respectively.

Odorant-binding proteins display high affinities for behavioral attractants and repellents in the natural predator Chrysopa pallens.

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Li, Zhao-Qun; Zhang, Shuai; Luo, Jun-Yu; Wang, Si-Bao; Dong, Shuang-Lin; Cui, Jin-Jie

2015-07-01

Chrysopa pallens is an important natural predator of various pests in many different cropping systems. Understanding the sophisticated olfactory system of insect antennae is crucial for studying the physiological bases of olfaction and could also help enhance the effectiveness of C. pallens in biological control. However, functional studies of the olfactory genes in C. pallens are still lacking. In this study, we cloned five odorant-binding protein (OBP) genes from C. pallens (CpalOBPs). Quantitative RT-PCR results indicated that the five CpalOBPs had different tissue expression profiles. Ligand-binding assays showed that farnesol, farnesene, cis-3-hexenyl hexanoate, geranylacetone, beta-ionone, octyl aldehyde, decanal, nerolidol (Kipallens. Among them, farnesene and its corresponding alcohol, farnesol, elicited remarkable repellent behavioral responses from C. pallens. Our study provides several compounds that could be selected to develop slow-release agents that attract/repel C. pallens and to improve the search for strategies to eliminate insect pests. Copyright © 2015 Elsevier Inc. All rights reserved.

Experimental use of two standard tick collection methods to evaluate the relative effectiveness of several plant-derived and synthetic repellents against Ixodes scapularis and Amblyomma americanum (Acari: Ixodidae).

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Schulze, Terry L; Jordan, Robert A; Dolan, Marc C

2011-12-01

We used two standard tick collection methods to test the relative effectiveness of two natural product compounds (nootkatone and carvacrol, classified as an eremophilene sesquiterpene and a monoterpene, respectively, that are derived from botanical sources) with commercially-available plant-derived (EcoSMART Organic Insect Repellent, comprised of plant essential oils) and permethrin-based (Repel Permanone) repellents against Ixodes scapularis Say and Amblyomma americanum (L.). Cloth drags were equally effective in sampling both species of host-seeking nymphs, whereas CO, traps attracted primarily A. americanum. All four repellents performed well on drags, with nootkatone and Permanone Repel (100% repelled through 14 d) slightly more effective than carvacrol and EcoSMART (90.7% and 97.7% repelled at 14 d, respectively) at repelling I. scapularis nymphs. Although the same trend in percent repellency was noted in the CO2 trap trial against both A. americanum nymphs and adults, EcoSMART outperformed Permanone in repelling A. Americanum nymphs after 14 d in the drag trial. Generally, the effectiveness of all repellents tested declined over time. The use of tick drags and CO2 traps was rapid, inexpensive, and easy to use in determining the relative effectiveness of repellents in the field.

U.S. laboratory and field trials of metofluthrin (SumiOne) emanators for reducing mosquito biting outdoors.

Science.gov (United States)

Lucas, J R; Shono, Y; Iwasaki, T; Ishiwatari, T; Spero, N; Benzon, G

2007-03-01

Metofluthrin (SumiOne is a novel, vapor-active pyrethroid that is highly effective against mosquitoes. Laboratory and field trials were conducted in the United States to evaluate the mosquito repellent activity of metofluthrin-treated paper substrates ("emanators"). Initial studies were conducted to evaluate the field performance of 900-cm(2) paper fan emanators impregnated with 160 mg metofluthrin, where Aedes canadensis was the predominant species. Emanators reduced landing rates on human volunteers by between 85% and 100% compared to untreated controls. Subsequent tests with 4,000-cm(2) paper strip emanators impregnated with 200 mg metofluthrin were conducted in a wind tunnel as a precursor to conducting field trials using human bait and laboratory-reared Aedes aegypti. Paper strips, which were pre-aged in a fume hood to determine duration of protection, gave 89-91% reductions in landing rates compared with controls. Similar reductions in biting activity were also noted. Following these tests, field trials to assess effect on landing rates were conducted with emanators positioned 1.22 m on either side of volunteers protected from biting by Tyvek suits, with pre- and posttreatment counts being made. In Florida (predominantly Ochlerotatus spp.) 91-95% reductions were noted 10-30 min after emanators were deployed, while in Washington State (mostly Aedes vexans) 95-97% reductions were observed. These results demonstrate that metofluthrin-treated emanators are highly effective at repelling mosquitoes.

Insecticidal, repellent and fungicidal properties of novel trifluoromethylphenyl amides.

Science.gov (United States)

Tsikolia, Maia; Bernier, Ulrich R; Coy, Monique R; Chalaire, Katelyn C; Becnel, James J; Agramonte, Natasha M; Tabanca, Nurhayat; Wedge, David E; Clark, Gary G; Linthicum, Kenneth J; Swale, Daniel R; Bloomquist, Jeffrey R

2013-09-01

Twenty trifluoromethylphenyl amides were synthesized and evaluated as fungicides and as mosquito toxicants and repellents. Against Aedes aegypti larvae, N-(2,6-dichloro-4-(trifluoromethyl)phenyl)-3,5-dinitrobenzamide (1e) was the most toxic compound (24 h LC50 1940 nM), while against adults N-(2,6-dichloro-4-(trifluoromethyl)phenyl)-2,2,2-trifluoroacetamide (1c) was most active (24 h LD50 19.182 nM, 0.5 μL/insect). However, the 24 h LC50 and LD50 values of fipronil against Ae. aegypti larvae and adults were significantly lower: 13.55 nM and 0.787 × 10(-4) nM, respectively. Compound 1c was also active against Drosophila melanogaster adults with 24 h LC50 values of 5.6 and 4.9 μg/cm(2) for the Oregon-R and 1675 strains, respectively. Fipronil had LC50 values of 0.004 and 0.017 μg/cm(2) against the two strains of D. melanogaster, respectively. In repellency bioassays against female Ae. aegypti, 2,2,2-trifluoro-N-(2-(trifluoromethyl)phenyl)acetamide (4c) had the highest repellent potency with a minimum effective dosage (MED) of 0.039 μmol/cm(2) compared to DEET (MED of 0.091 μmol/cm(2)). Compound N-(2-(trifluoromethyl)phenyl)hexanamide (4a) had an MED of 0.091 μmol/cm(2) which was comparable to DEET. Compound 4c was the most potent fungicide against Phomopsis obscurans. Several trends were discerned between the structural configuration of these molecules and the effect of structural changes on toxicity and repellency. Para- or meta- trifluoromethylphenyl amides with an aromatic ring attached to the carbonyl carbon showed higher toxicity against Ae. aegypti larvae, than ortho- trifluoromethylphenyl amides. Ortho- trifluoromethylphenyl amides with trifluoromethyl or alkyl group attached to the carbonyl carbon produced higher repellent activity against female Ae. aegypti and Anopheles albimanus than meta- or para- trifluoromethylphenyl amides. The presence of 2,6-dichloro- substitution on the phenyl ring of the amide had an influence on larvicidal and repellent

Phenological stage effect on phenolic composition and repellent potential of Mentha pulegium against Tribolium castaneum and Lasioderma serricorne

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Nidhal Salem

2018-01-01

Full Text Available Objective: To elucidate for the first time the phenological stage effect on polyphenol, flavonoid and proanthocyanidin contents of pennyroyal (Mentha pulegium as well as their antioxidant capacities and insecticidal potentials against Tribolium castaneum and Lasioderma serricorne. Methods: Crude methanol extracts from pennyroyal (Mentha pulegium aerial parts were evaluated for their antiradical, reducing power activities and repellent potentials against selected coleopteran insects during different phenological stages. Results: Phenolic contents of pennyroyal aerial parts and their antioxidant effects were significantly dependent on maturity stage of the plant. The maximum of phenol production was reached during the full flowering stage. Apigenin was the major phenol in Mentha pulegium with an amount of 6.01 mg/g of dry vegetable matter during this period. Nevertheless, at fructification stage, the highest antioxidant activity was not related to high phenolic content. The repulsive effect of pennyroyal extract showed that Lasioderma serricorne was more susceptible to pennyroyal extract than Tribolium castaneum with corresponding median repellent dose values of 0.124 and 0.006 mg/mL respectively. Moreover, great differences in insect repulsion depending on extract concentrations, exposure time and developmental stage was observed. For the lowest concentration (0.125 mg/mL, the repellent effect against Tribolium reached its maximum (90% during the fructification stage (after 24 h of exposure while this repellent effect was 80% during the vegetative stage. Conclusions: Due to the strong insecticidal potential of pennyroyal extracts, this study highlights the therapeutic properties of this plant and encourages its use as a safer, environmental-friendly and efficient insecticide in food industry.

Potential topical natural repellent against Ae. aegypti, Culex sp. and Anopheles sp. mosquitoes

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Dewi Nur Hodijah

2014-08-01

Full Text Available AbstrakLatar belakang:Minyak atsiri daun sirih diketahui mempunyai daya proteksi. Dibuatkan losion berdasarkan pengantar sediaan farmasi yang ditambahkan minyak atsiri daun nilam. Sediaan losion dipilih agar dapat menempel lebih lama di permukaan kulit. Tujuan penelitian ini untuk membandingkan daya proteksi antara losion dengan penambahan minyak nilam dan losion tanpa penambahan minyak nilam dibandingkan daya proteksi dengan DEET. Metode: Penelitian ini merupakan penelitian eksperimental laboratorium. Semua nyamuk uji berasal dari insektarium laboratorium penelitian kesehatan Loka litbang P2B2 Ciamis. Konsentrasi minyak atsiri daun sirih dalam losion adalah 4%; konsentrasi minyak nilam sebagai zat pengikat adalah 0,4%. Formula yang digunakan yaitu formula dasar yang ada pada pengantar sediaan farmasi. Uji repelensi dilakukan dengan menggunakan metoda yang direkomendasikan oleh Komisi pestisida.Hasil: Dihasilkan formulasi losion yang stabil dan masih memenuhi standar formulasi sediaan. Berdasarkan hasil, diperoleh data bahwa DEET dan losion hasil modifikasi memiliki rata-rata daya proteksi di atas 90% selama 6 jam terhadap nyamuk Ae.aegypti dan Culex sp. Kesimpulan: Penambahan minyak nilam pada losion sirih dapat meningkatkan daya proteksi terhadap hinggapan nyamuk Ae. aegypti dan Culex sp. (Health Science Indones 2014;1:44-8Kata kunci:repelen alamiah, minyak atsiri, daun sirih, daun nilam, Ae. aegypti, Culex sp.AbstractBackground: Betel leaf essential oil lotion has been known to have insect repellent properties. A lotion was made based on a pharmaceutical formula from a monograph where patchouli leaf essential oil was added. A lotion preparation was intended to enhance adherence of the formula on the surface of the skin. The purpose of this study was to compare protection percentage of lotion with patchouli oil and without patchouli oil lotion compared to DEET.Methods: This study is an experimental laboratory-based research. All mosquitoes

Mosquito repellent properties of Delonix elata (L. gamble (Family: Fabaceae against filariasis vector, Culex quinquefasciatus Say. (Diptera: Culicidae

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Marimuthu Govindarajan

2014-02-01

Full Text Available Objective: To determine the repellent activity of hexane, ethyl acetate, benzene, chloroform and methanol extract of Delonix elata (D. elata leaf and seed against Culex quinquefasciatus (Cx. quinquefasciatus. Methods: Evaluation was carried out in a net cage (45 cm伊30 cm伊25 cm containing 100 blood starved female mosquitoes of Cx. quinquefasciatus. Repellent activity was carried out in the laboratory conditions according to the WHO 2009 protocol. Plant crude extracts of D. elata were applied at 1.0, 2.5, and 5.0 mg/cm2 separately in the exposed fore arm of study subjects. Ethanol was used as the sole control. Results: In this study, the applied plant crude extracts were observed to protect against mosquito bites. There were no allergic reactions experienced by the study subjects. The repellent activity of the extract was dependent on the strength of the extract. Among the tested solvents, the leaf and seed methanol extract showed the maximum efficacy. The highest concentration of 5.0 mg/cm2 provided over 150 min and 120 min protection, respectively. Conclusions: Crude extracts of D. elata exhibit the potential for controlling Cx. quinquefasciatus, the mosquito vector of filariasis.

Use of chemosensory cues as repellents for sea lamprey: Potential directions for population management

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Imre, I.; Brown, G.E.; Bergstedt, R.A.; McDonald, R.

2010-01-01

Sea lamprey invaded the Great Lakes in the early 20th century and caused an abrupt decline in the population densities of several native fish species. The integrated management of this invasive species is composed of chemical (lampricide) applications, low-head barrier dams, adult trapping and sterile male release. Recently, there has been an increased emphasis on the development of control methods alternative to lampricide applications. We propose as an alternative-control method the use of chemosensory cues as repellents for sea lamprey population management. Based on the available evidence at this time, we suggest that injury-released chemical alarm cues show promise as repellents for sea lamprey and further research should be directed at determining whether sea lamprey show an avoidance response to these types of chemosensory cues. From a management perspective, these chemosensory cues could be used to restrict sea lamprey access to spawning grounds. Repellents could also be used together with attractants like sex pheromones to manipulate sea lamprey behavior, similar to the "push-pull" strategies utilized with insect pests. ?? 2010 Elsevier B.V.

Enhanced repellency of binary mixtures of Zanthoxylum armatum seed oil, vanillin, and their aerosols to mosquitoes under laboratory and field conditions.

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Kwon, Hyung Wook; Kim, Soon-Il; Chang, Kyu-Sik; Clark, J Marshall; Ahn, Young-Joon

2011-01-01

The repellency of Zanthoxylum armatum seed oil (ZA-SO), alone or in combination with vanillin (VA), its six major constituents, and another four major previously known Zanthoxylum piperitum fruit oil constituents, as well as aerosol products containing 5 or 10% ZA-SO and 5% VA, was evaluated against female Aedes aegypti in laboratory and field studies. Results were then compared with those of N,N-diethyl-3-methylbenzamide (DEET) as a standard. Hand in cage laboratory tests showed that 0.2, 0.1, and 0.05 mg/cm2 ZA-SO resulted in > 92% protection through 30-min postexposure and was not significantly different than 0.05 mg/cm2 DEET. Skin treated with linalool and limonene (from Z. armatum) provided > 80% repellency to female Ae. aegypti at 10-min exposure, whereas cuminaldehyde, citronellal, geranyl acetate, and cuminyl alcohol (from Zanthoxylum piperitum) provided > 90% protection during this same time period. Only cuminaldehyde and citronellal provided complete protection comparable to DEET at 10-min postexposure. After that time, repellency of all plant constituents to mosquitoes was considerably decreased (biting and nuisance caused by mosquitoes.

Fumigant and repellent properties of sesquiterpene-rich essential oil from Teucrium polium subsp. capitatum (L.)

Institute of Scientific and Technical Information of China (English)

Abbas Khani; Monireh Heydarian

2014-01-01

Objective:To test fumigant and repellent properties of sesquiterpene-rich essential oil from Teucrium polium subsp.capitatum(L.).Methods:The fumigant toxicity test was performed at(27±1)℃,(65±5)% relative humidity, and under darkness condition and24 h exposure time.The chemical composition of the isolated oils was examined by gas chromatography-mass spectrometry.Results:The major compounds wereα-cadinol(46.2%), caryophyllene oxide(25.9%), α muurolol epi(8.1%), cadalene(3.7%) and longiverbenone(2.9%).In all cases, considerable differences in mortality of insect to essential oil vapor were observed in different concentrations and exposure times.Callosobruchus maculatus(C. maculates)(LC50=148.9 μL/L air) was more susceptible to the tested plant product thanTeucrium castaneum(T. castaneum) (LC50=360.2 μL/L air) based onLC50 values.In the present investigation, the concentration of3 μL /mL acetone showed60% and52% repellency againstT. casteneumandC. maculatus adults, respectively.Conclusions:The results suggests that sesquiterpene-rich essential oils from the tested plant could be used as a potential control agent for stored-product insects.

The development of a murine model for Forcipomyia taiwana (biting midge) allergy.

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Lee, Mey-Fann; Yang, Kai-Jei; Wang, Nancy M; Chiu, Yung-Tsung; Chen, Pei-Chih; Chen, Yi-Hsing

2014-01-01

Forcipomyia taiwana (biting midge) allergy is the most prevalent biting insect allergy in Taiwan. An animal model corresponding to the human immuno-pathologic features of midge allergy is needed for investigating the mechanisms and therapies. This study successfully developed a murine model of Forcipomyia taiwana allergy. BALB/c mice were sensitized intra-peritoneally with midge extract on days 0, 7, 14, 21 then intra-dermally on days 28, 31 and 35. Serum midge-specific IgE, IgG1, and IgG2a were measured every 14 days by indirect ELISA. The mice were challenged intradermally with midge extract at day 40 and then sacrificed. Proliferation and cytokine production of splenocytes after stimulation with midge extract were determined by MTT assay and ELISA, respectively. The cytokine mRNA expression in response to midge stimulation was analyzed by RT-PCR. Serum IgE, total IgG, and IgG1 antibody levels against midge extract were significantly higher in the midge-sensitized mice than in the control mice. After the two-step sensitization, all mice in the midge-sensitized group displayed immediate itch and plasma extravasation reactions in response to challenge with midge extract. Skin histology from midge-sensitized mice showed marked eosinophil and lymphocyte infiltrations similar to that observed in humans. Stimulation of murine splenocytes with midge extract elicited significant proliferation, IL-4, IL-10, IL-13 and IFN-γ protein production, and up-regulation of mRNA in a dose-dependent manner in the midge-sensitized group, but not in the control group. A murine model of midge bite allergy has been successfully developed using a two-step sensitization protocol. The sensitized mice have very similar clinical and immunologic reactions to challenge with midge proteins as the reactions of human to midge bites. This murine model may be a useful platform for future research and the development of treatment strategies for insect bite allergy.

Isolation and identification of mosquito (Aedes aegypti) biting deterrent fatty acids from male inflorescences of breadfruit (Artocarpus altilis (Parkinson)Fosberg)

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Dried male inflorescences of breadfruit (Artocarpus altilis, Moraceae) are burned in communities throughout Oceania to repel flying insects, including mosquitoes. This study was conducted to identify chemicals responsible for mosquito deterrence. Various crude extracts were evaluated, and the most a...

A simple trapping method to estimate abundances of blood-sucking flying insects in avian nests

NARCIS (Netherlands)

Tomás, G.; Merino, S.; Martínez-de la Puente, J.; Moreno, J.; Morales, J.; Lobato, E.

2008-01-01

[KEYWORDS: birds; biting midges; blackflies; blood parasite-insect vector-vertebrate host relationships; Ceratopogonidae; Culicoides; distance to water sources; insecticide treatment; sampling methods; Simuliidae

Biting deterrence and insecticidal activity of hydrazide-hydrazones and their corresponding 3-acetyl-2,5-disubstituted-2,3-dihydro-1,3,4-oxadiazoles against Aedes aegypti.

Science.gov (United States)

Tabanca, Nurhayat; Ali, Abbas; Bernier, Ulrich R; Khan, Ikhlas A; Kocyigit-Kaymakcioglu, Bedia; Oruç-Emre, Emine E; Unsalan, Seda; Rollas, Sevim

2013-06-01

Taking into account the improvement in insecticidal activity by the inclusion of fluorine in the hydrazone moiety, the authors synthesized new 4-fluorobenzoic acid hydrazides and 3-acetyl-2,5-disubstituted-2,3-dihydro-1,3,4-oxadiazoles, substituting a phenyl group or a heteroaryl ring carrying one or two atoms of F, Cl and Br, and investigated their biting deterrent and larvicidal activities against Aedes aegypti for the first time. The compound 3-acetyl-5-(4-fluorophenyl)-2-[4-(dimethylamino)phenyl]-2,3-dihydro-1,3,4-oxadiazole (17) produced the highest biting deterrent activity (BDI = 1.025) against Ae. Aegypti, followed by 4-fluorobenzoic acid [(phenyl)methylene] hydrazide (1). These activity results were similar to those of N,N-diethyl-meta-toluamide (DEET), which showed a proportion not biting of 0.8-0.92. When compounds 1 and 17 were tested on cloth worn on human volunteers, compound 1 was not repellent for some volunteers until present in excess of 500 nmol cm(-2) , while compound 17 was not repellent at the highest concentration tested (1685 nmol cm(-2) ). In the larvicidal screening bioassays, only compounds 10, 11, 12 and 17 showed 100% mortality at the highest screening dose of 100 ppm against Ae. aegypti larvae. Compounds 11 and 12 with LD50 values of 24.1 and 30.9 ppm showed significantly higher mortality than 10 (80.3 ppm) and 17 (58.7 ppm) at 24-h post-treatment. The insecticidal and biting deterrent activities were correlated with the presence of a halogen atom on the phenyl or heteroaryl substituent of the hydrazone moiety. © 2012 Society of Chemical Industry.

Nectar Theft and Floral Ant-Repellence: A Link between Nectar Volume and Ant-Repellent Traits?

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Ballantyne, Gavin; Willmer, Pat

2012-01-01

As flower visitors, ants rarely benefit a plant. They are poor pollinators, and can also disrupt pollination by deterring other flower visitors, or by stealing nectar. Some plant species therefore possess floral ant-repelling traits. But why do particular species have such traits when others do not? In a dry forest in Costa Rica, of 49 plant species around a third were ant-repellent at very close proximity to a common generalist ant species, usually via repellent pollen. Repellence was positively correlated with the presence of large nectar volumes. Repellent traits affected ant species differently, some influencing the behaviour of just a few species and others producing more generalised ant-repellence. Our results suggest that ant-repellent floral traits may often not be pleiotropic, but instead could have been selected for as a defence against ant thieves in plant species that invest in large volumes of nectar. This conclusion highlights to the importance of research into the cost of nectar production in future studies into ant-flower interactions. PMID:22952793

Insecticidal and repellant activities of plants oil against stored grain pest, Tribolium castaneum (Herbst (Coleoptera:Tenebrionidae

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S.R.Pugazhvendan

2012-05-01

Full Text Available Objective: The present investigation was aimed to assess the impact of five plants oil for their insecticidal and repellent activity against Tribolium castaneum (Herbst, a stored grain pest and they were tested in the laboratory. Method: Five plants oil Citrus autantium, Cinnamomum zeylanicum, Gaultheria fragrantissima, Lavandula officinalis, and Ocimum sanctum were evaluated for their insecticidal and repellent activities against T. castaneum by adapting the standard protocol in vitro. Results: In Tulsi oil showed powerful repellent against T. castaneum beetles at both the concentration and this property can be clearly seen from the values at 5毺 1 (-0.60 and -0.73 in 1h and 6hr respectively and 10毺 1 (-0.56 and -0.81 in 1h and 6h respectively. Tulsi oil had more repelling property than other oil tested here against T. castaneum. Maximum percentage of mortality (76 and 92% at 48h and 72 hours after treatment respectively in Tulsi oil. Wintergreen oil showed 86% mortality at 72 hours after treatment. Conclusions: The present work for botanical products to control the insect pest of stored grain T. castaneum .These results suggest the presence of actives principles in the plant oils. Further exploration of active principles and their structural elucidations are underway.

For t 2 DNA vaccine prevents Forcipomyia taiwana (biting midge) allergy in a mouse model.

Science.gov (United States)

Lee, M-F; Song, P-P; Lin, T-M; Chiu, Y-T; Chen, Y-H

2016-04-01

Forcipomyia taiwana (biting midge) is the most prevalent allergenic biting insect in Taiwan, and 60% of the exposed subjects develop allergic reactions. Subjects with insect allergy frequently limit their outdoor activities to avoid the annoyingly intense itchy allergic reactions, leading to significant worsening of their quality of life. Allergen-specific immunotherapy is the only known therapy that provides long-term host immune tolerance to the allergen, but is time-consuming and cumbersome. This study tested whether the For t 2 DNA vaccine can prevent allergic symptoms in For t 2-sensitized mice. Two consecutive shots of For t 2 DNA vaccine were given to mice with a 7-day interval before sensitization with recombinant For t 2 proteins, using the two-step sensitization protocol reported previously. The For t 2 DNA vaccine at 50 μg prevented the production of For t 2-specific IgE (P allergy in the future. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Reliable quantification of bite-force performance requires use of appropriate biting substrate and standardization of bite out-lever.

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Lappin, A Kristopher; Jones, Marc E H

2014-12-15

Bite-force performance is an ecologically important measure of whole-organism performance that shapes dietary breadth and feeding strategies and, in some taxa, determines reproductive success. It also is a metric that is crucial to testing and evaluating biomechanical models. We reviewed nearly 100 published studies of a range of taxa that incorporate direct in vivo measurements of bite force. Problematically, methods of data collection and processing vary considerably among studies. In particular, there is little consensus on the appropriate substrate to use on the biting surface of force transducers. In addition, the bite out-lever, defined as the distance from the fulcrum (i.e. jaw joint) to the position along the jawline at which the jaws engage the transducer, is rarely taken into account. We examined the effect of bite substrate and bite out-lever on bite-force estimates in a diverse sample of lizards. Results indicate that both variables have a significant impact on the accuracy of measurements. Maximum bite force is significantly greater using leather as the biting substrate compared with a metal substrate. Less-forceful bites on metal are likely due to inhibitory feedback from mechanoreceptors that prevent damage to the feeding apparatus. Standardization of bite out-lever affected which trial produced maximum performance for a given individual. Indeed, maximum bite force is usually underestimated without standardization because it is expected to be greatest at the minimum out-lever (i.e. back of the jaws), which in studies is rarely targeted with success. We assert that future studies should use a pliable substrate, such as leather, and use appropriate standardization for bite out-lever. © 2014. Published by The Company of Biologists Ltd.

Small-scale field evaluation of push-pull system against early- and outdoor-biting malaria mosquitoes in an area of high pyrethroid resistance in Tanzania [version 1; referees: 2 approved

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Arnold S. Mmbando

2017-11-01

Full Text Available Background: Despite high coverage of indoor interventions like insecticide-treated nets, mosquito-borne infections persist, partly because of outdoor-biting, early-biting and insecticide-resistant vectors. Push-pull systems, where mosquitoes are repelled from humans and attracted to nearby lethal targets, may constitute effective complementary interventions. Methods: A partially randomized cross-over design was used to test efficacy of push-pull in four experimental huts and four local houses, in an area with high pyrethroid resistance in Tanzania. The push-pull system consisted of 1.1% or 2.2% w/v transfluthrin repellent dispensers and an outdoor lure-and-kill device (odour-baited mosquito landing box. Matching controls were set up without push-pull. Adult male volunteers collected mosquitoes attempting to bite them outdoors, but collections were also done indoors using exit traps in experimental huts and by volunteers in the local houses. The collections were done hourly (1830hrs-0730hrs and mosquito catches compared between push-pull and controls. An. gambiae s.l. and An. funestus s.l. were assessed by PCR to identify sibling species, and ELISA to detect Plasmodium falciparum and blood meal sources. Results: Push-pull in experimental huts reduced outdoor-biting for An. arabiensis and Mansonia species by 30% and 41.5% respectively. However, the reductions were marginal and insignificant for An. funestus (12.2%; p>0.05 and Culex (5%; p>0.05. Highest protection against all species occurred before 2200hrs. There was no significant difference in number of mosquitoes inside exit traps in huts with or without push-pull. In local households, push-pull significantly reduced indoor and outdoor-biting of An. arabiensis by 48% and 25% respectively, but had no effect on other species. Conclusion: This push-pull system offered modest protection against outdoor-biting An. arabiensis, without increasing indoor mosquito densities. Additional experimentation

The neonicotinoid insecticide imidacloprid repels pollinating flies and beetles at field-realistic concentrations.

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Amy H Easton

Full Text Available Neonicotinoids are widely used systemic insecticides which, when applied to flowering crops, are translocated to the nectar and pollen where they may impact upon pollinators. Given global concerns over pollinator declines, this potential impact has recently received much attention. Field exposure of pollinators to neonicotinoids depends on the concentrations present in flowering crops and the degree to which pollinators choose to feed upon them. Here we describe a simple experiment using paired yellow pan traps with or without insecticide to assess whether the commonly used neonicotinoid imidacloprid repels or attracts flying insects. Both Diptera and Coleoptera exhibited marked avoidance of traps containing imidacloprid at a field-realistic dose of 1 µg L(-1, with Diptera avoiding concentrations as low as 0.01 µg L(-1. This is to our knowledge the first evidence for any biological activity at such low concentrations, which are below the limits of laboratory detection using most commonly available techniques. Catch of spiders in pan traps was also slightly reduced by the highest concentrations of imidacloprid used (1 µg L(-1, but catch was increased by lower concentrations. It remains to be seen if the repellent effect on insects occurs when neonicotinoids are present in real flowers, but if so then this could have implications for exposure of pollinators to neonicotinoids and for crop pollination.

Human bites - self-care

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Bites - human - self-care ... Human bites can occur in 2 ways: If someone bites you If your hand comes into contact ... bite to express anger or other negative feelings. Human bites may be more dangerous than animal bites. ...

In vitro induction of functional allergen-specific CD4+ CD25high Treg cells in horses affected with insect bite hypersensitivity.

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Hamza, E; Akdis, C A; Wagner, B; Steinbach, F; Marti, E

2013-08-01

Insect bite hypersensitivity (IBH) is a recurrent allergic dermatitis of horses with similarities to human atopic eczema, caused by bites of insects of the genus Culicoides. Previous studies suggested a dysregulated T cell tolerance to Culicoides allergen in IBH-affected horses. We have investigated whether the suppressive function of CD4(+) CD25(high) cells is impaired in IBH-affected horses and possible ways to restore it. CD4(+) CD25(-) cells sorted from peripheral blood mononuclear cells (PBMC) were stimulated with irradiated autologous PBMC pulsed with Culicoides or tetanus toxoid as control antigen, in the presence of CD4(+) CD25(high) cells. Furthermore, Culicoides-specific CD4(+) CD25(high) regulatory cells were expanded or induced from CD4(+) CD25(-) cells in vitro in the presence of a combination of rIL-2 and rTGF-β1 (rIL-2/rTGF-β1) or of retinoic acid and rapamycin (RetA/Rapa). Proliferation was determined by [(3) H] thymidine incorporation and cytokine production measured by flow cytometry. The ability of Culicoides- but not tetanus-stimulated CD4(+) CD25(high) cells to suppress proliferation of CD4(+) CD25(-) cells was significantly lower in IBH-affected horses (28%) than in healthy controls (86%). The decreased suppression in IBH-affected horses was associated with a significantly higher proportion of IL-4(+) cells and a lower percentage of FoxP3(+) IL-10(+) compared to controls. Addition of rIL-2/rTGF-β1 or of RetA/Rapa to Culicoides-stimulated CD4(+) CD25(high) cells from IBH-affected horses significantly increased the proportion of FoxP3(+) IL-10(+) cells. We also found that RetA/Rapa induced a more significant decrease in the frequency of IL-4(+) cells than rIL-2/rTGF-β1. Moreover, the suppressive activity of Culicoides-stimulated CD4(+) CD25(high) cells was significantly restored by both rIL-2/rTGF-β1and RetA/Rapa, albeit in an antigen-unspecific manner. In contrast, in vitro induced Culicoides-specific CD4(+) CD25(high) cells suppressed

Development of Anti-Insect Microencapsulated Polypropylene Films Using a Large Scale Film Coating System.

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Song, Ah Young; Choi, Ha Young; Lee, Eun Song; Han, Jaejoon; Min, Sea C

2018-04-01

Films containing microencapsulated cinnamon oil (CO) were developed using a large-scale production system to protect against the Indian meal moth (Plodia interpunctella). CO at concentrations of 0%, 0.8%, or 1.7% (w/w ink mixture) was microencapsulated with polyvinyl alcohol. The microencapsulated CO emulsion was mixed with ink (47% or 59%, w/w) and thinner (20% or 25%, w/w) and coated on polypropylene (PP) films. The PP film was then laminated with a low-density polyethylene (LDPE) film on the coated side. The film with microencapsulated CO at 1.7% repelled P. interpunctella most effectively. Microencapsulation did not negatively affect insect repelling activity. The release rate of cinnamaldehyde, an active repellent, was lower when CO was microencapsulated than that in the absence of microencapsulation. Thermogravimetric analysis exhibited that microencapsulation prevented the volatilization of CO. The tensile strength, percentage elongation at break, elastic modulus, and water vapor permeability of the films indicated that microencapsulation did not affect the tensile and moisture barrier properties (P > 0.05). The results of this study suggest that effective films for the prevention of Indian meal moth invasion can be produced by the microencapsulation of CO using a large-scale film production system. Low-density polyethylene-laminated polypropylene films printed with ink incorporating microencapsulated cinnamon oil using a large-scale film production system effectively repelled Indian meal moth larvae. Without altering the tensile and moisture barrier properties of the film, microencapsulation resulted in the release of an active repellent for extended periods with a high thermal stability of cinnamon oil, enabling commercial film production at high temperatures. This anti-insect film system may have applications to other food-packaging films that use the same ink-printing platform. © 2018 Institute of Food Technologists®.

Sharks senses and shark repellents.

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Hart, Nathan S; Collin, Shaun P

2015-01-01

Despite over 70 years of research on shark repellents, few practical and reliable solutions to prevent shark attacks on humans or reduce shark bycatch and depredation in commercial fisheries have been developed. In large part, this deficiency stems from a lack of fundamental knowledge of the sensory cues that drive predatory behavior in sharks. However, the widespread use of shark repellents is also hampered by the physical constraints and technical or logistical difficulties of deploying substances or devices in an open-water marine environment to prevent an unpredictable interaction with a complex animal. Here, we summarize the key attributes of the various sensory systems of sharks and highlight residual knowledge gaps that are relevant to the development of effective shark repellents. We also review the most recent advances in shark repellent technology within the broader historical context of research on shark repellents and shark sensory systems. We conclude with suggestions for future research that may enhance the efficacy of shark repellent devices, in particular, the continued need for basic research on shark sensory biology and the use of a multi-sensory approach when developing or deploying shark repellent technology. © 2014 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.

Larvicidal and repellent effect of some Tribulus terrestris L., (Zygophyllaceae extracts against the dengue fever mosquito, Aedes aegypti (Diptera: Culicidae

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Tarek M.Y. El-Sheikh

2016-01-01

Full Text Available Aedes aegypti transmits etiologic agents of yellow fever and dengue. Vaccine for dengue virus is not available and vector control is essential to minimize dengue incidence. The larvicidal and repellent effect of the crude ethanol, acetone and petroleum ether extract leaves of Tribulus terrestris, against 3rd instar larvae and adults of mosquito, Ae. aegypti the vector of dengue fever was evaluated. The efficacy of petroleum ether extract seemed to be more effective with LC50 64.6 ppm followed by acetone extract with LC50 173.2 ppm and finally ethanolic extract with LC50 376.4 ppm. Moreover, the acetone and petroleum ether extracts exerted a highly delayed toxic effect on the pupae and adults resulted from treated larvae, where the pupal mortality was 57.1% and 100% at concentrations 400 and 100 ppm, respectively. Also, the petroleum ether and acetone extracts showed reduction effects on adult emergence. The repellent action of the plant extracts tested was varied depending on the solvent used in extraction and the dose of the extract. The most effective plant extract that evoked 100% repellency or biting deterrence was petroleum ether extract at a dose of 1.5 mg/cm2 compared with 100% repellency for commercial formulation, N,N-diethyl-3-methylbenzamide (DEET at the same dose. Hence, these extracts can be used as an effective alternative to the existing synthetic pesticides for the control of Ae. aegypti.

Fast and Powerful: Biomechanics and Bite Forces of the Mandibles in the American Cockroach Periplaneta americana.

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Tom Weihmann

Full Text Available Knowing the functionality and capabilities of masticatory apparatuses is essential for the ecological classification of jawed organisms. Nevertheless insects, especially with their outstanding high species number providing an overwhelming morphological diversity, are notoriously underexplored with respect to maximum bite forces and their dependency on the mandible opening angles. Aiming for a general understanding of insect biting, we examined the generalist feeding cockroach Periplaneta americana, characterized by its primitive chewing mouth parts. We measured active isometric bite forces and passive forces caused by joint resistance over the entire mandibular range with a custom-built 2D force transducer. The opening angle of the mandibles was quantified by using a video system. With respect to the effective mechanical advantage of the mandibles and the cross-section areas, we calculated the forces exerted by the mandible closer muscles and the corresponding muscle stress values. Comparisons with the scarce data available revealed close similarities of the cockroaches' mandible closer stress values (58 N/cm2 to that of smaller specialist carnivorous ground beetles, but strikingly higher values than in larger stag beetles. In contrast to available datasets our results imply the activity of faster and slower muscle fibres, with the latter becoming active only when the animals chew on tough material which requires repetitive, hard biting. Under such circumstances the coactivity of fast and slow fibres provides a force boost which is not available during short-term activities, since long latencies prevent a specific effective employment of the slow fibres in this case.

Validated RP-HPLC/DAD Method for the Quantification of Insect Repellent Ethyl 2-Aminobenzoate in Membrane-Moderated Matrix Type Monolithic Polymeric Device.

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Islam, Johirul; Zaman, Kamaruz; Chakrabarti, Srijita; Sharma Bora, Nilutpal; Mandal, Santa; Pratim Pathak, Manash; Srinivas Raju, Pakalapati; Chattopadhyay, Pronobesh

2017-07-01

A simple, accurate and sensitive reversed-phase high-performance liquid chromatographic (RP-HPLC) method has been developed for the estimation of ethyl 2-aminobenzoate (EAB) in a matrix type monolithic polymeric device and validated as per the International Conference on Harmonization guidelines. The analysis was performed isocratically on a ZORBAX Eclipse plus C18 analytical column (250 × 4.4 mm, 5 μm) and a diode array detector (DAD) using acetonitrile and water (75:25 v/v) as the mobile phase by keeping the flow-rate constant at 1.0 mL/min. Determination of EAB was not interfered in the presence of excipients. Inter- and intra-day relative standard deviations were not higher than 2%. Mean recovery was between 98.7 and 101.3%. Calibration curve was linear in the concentration range of 0.5-10 µg/mL. Limits of detection and quantification were 0.19 and 0.60 µg/mL, respectively. Thus, the present report put forward a novel method for the estimation of EAB, an emerging insect repellent, by using RP-HPLC technique. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Animal bites - self-care

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Bites - animals - self-care ... Most animal bites come from pets. Dog bites are common and most often happen to children. Cat bites are ... which can cause deeper puncture wounds. Most other animal bites are caused by stray or wild animals, ...

Cat and Dog Bites

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... Wellness Staying Healthy Pets and Animals Cat and Dog Bites Cat and Dog Bites Share Print Cat and dog bites are common injuries. A family pet or ... bites. Path to safety If a cat or dog bites you, you should: Wash the wound gently ...

orco mutant mosquitoes lose strong preference for humans and are not repelled by volatile DEET.

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DeGennaro, Matthew; McBride, Carolyn S; Seeholzer, Laura; Nakagawa, Takao; Dennis, Emily J; Goldman, Chloe; Jasinskiene, Nijole; James, Anthony A; Vosshall, Leslie B

2013-06-27

Female mosquitoes of some species are generalists and will blood-feed on a variety of vertebrate hosts, whereas others display marked host preference. Anopheles gambiae and Aedes aegypti have evolved a strong preference for humans, making them dangerously efficient vectors of malaria and Dengue haemorrhagic fever. Specific host odours probably drive this strong preference because other attractive cues, including body heat and exhaled carbon dioxide (CO2), are common to all warm-blooded hosts. Insects sense odours via several chemosensory receptor families, including the odorant receptors (ORs), membrane proteins that form heteromeric odour-gated ion channels comprising a variable ligand-selective subunit and an obligate co-receptor called Orco (ref. 6). Here we use zinc-finger nucleases to generate targeted mutations in the orco gene of A. aegypti to examine the contribution of Orco and the odorant receptor pathway to mosquito host selection and sensitivity to the insect repellent DEET (N,N-diethyl-meta-toluamide). orco mutant olfactory sensory neurons have greatly reduced spontaneous activity and lack odour-evoked responses. Behaviourally, orco mutant mosquitoes have severely reduced attraction to honey, an odour cue related to floral nectar, and do not respond to human scent in the absence of CO2. However, in the presence of CO2, female orco mutant mosquitoes retain strong attraction to both human and animal hosts, but no longer strongly prefer humans. orco mutant females are attracted to human hosts even in the presence of DEET, but are repelled upon contact, indicating that olfactory- and contact-mediated effects of DEET are mechanistically distinct. We conclude that the odorant receptor pathway is crucial for an anthropophilic vector mosquito to discriminate human from non-human hosts and to be effectively repelled by volatile DEET.

Is there a risk associated with the insect repellent DEET (N,N-diethyl-m-toluamide) commonly found in aquatic environments?

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Costanzo, S.D.; Watkinson, A.J.; Murby, E.J.; Kolpin, D.W.; Sandstrom, M.W.

2007-01-01

DEET (N,N-diethyl-m-toluamide) is the active ingredient of most commercial insect repellents. This compound has commonly been detected in aquatic water samples from around the world indicating that DEET is both mobile and persistent, despite earlier assumptions that DEET was unlikely to enter aquatic ecosystems. DEET's registration category does not require an ecological risk assessment, thus information on the ecological toxicity of DEET is sparse. This paper reviews the presence of DEET in aqueous samples from around the world (e.g. drinking water, streams, open seawater, groundwater and treated effluent) with reported DEET concentrations ranging from 40–3000 ng L− 1. In addition, new DEET data collected from 36 sites in coastal waterways from eastern Australia (detections ranging from 8 to 1500 ng L− 1) are examined. A summary of new and existing toxicity data are discussed with an emphasis on preparing a preliminary risk assessment for DEET in the aquatic environment. Collated information on DEET in the aquatic environment suggests risk to aquatic biota at observed environmental concentrations is minimal. However, the information available was not sufficient to conduct a full risk assessment due to data deficiencies in source characterisation, transport mechanisms, fate, and ecotoxicity studies. These risks warrant further investigation due to the high frequency that this organic contaminant is detected in aquatic environments around the world.

Prevention of infectious tick-borne diseases in humans: Comparative studies of the repellency of different dodecanoic acid-formulations against Ixodes ricinus ticks (Acari: Ixodidae

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Dautel Hans

2008-04-01

Full Text Available Abstract Background Ticks of the species Ixodes ricinus are the main vectors of Lyme Borreliosis and Tick-borne Encephalitis – two rapidly emerging diseases in Europe. Repellents provide a practical means of protection against tick bites and can therefore minimize the transmission of tick-borne diseases. We developed and tested seven different dodecanoic acid (DDA-formulations for their efficacy in repelling host-seeking nymphs of I. ricinus by laboratory screening. The ultimately selected formulation was then used for comparative investigations of commercially available tick repellents in humans. Methods Laboratory screening tests were performed using the Moving-object (MO bioassay. All test formulations contained 10% of the naturally occurring active substance DDA and differed only in terms of the quantitative and qualitative composition of inactive ingredients and fragrances. The test procedure used in the human bioassays is a modification of an assay described by the U.S. Environmental Protection Agency and recommended for regulatory affairs. Repellency was computed using the equation: R = 100 - NR/N × 100, where NR is the number of non-repelled ticks, and N is the respective number of control ticks. All investigations were conducted in a controlled laboratory environment offering standardized test conditions. Results All test formulations strongly repelled nymphs of I. ricinus (100-81% protection as shown by the MO-bioassay. The majority of ticks dropped off the treated surface of the heated rotating drum that served as the attractant (1 mg/cm2 repellent applied. The 10% DDA-based formulation, that produced the best results in laboratory screening, was as effective as the coconut oil-based reference product. The mean protection time of both preparations was generally similar and averaged 8 hours. Repellency investigations in humans showed that the most effective 10% DDA-based formulation (~1.67 mg/cm2 applied strongly avoided the

Animal Bites: First Aid

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First aid Animal bites: First aid Animal bites: First aid By Mayo Clinic Staff These guidelines can help you care for a minor animal bite, such ... 26, 2017 Original article: http://www.mayoclinic.org/first-aid/first-aid-animal-bites/basics/ART-20056591 . Mayo ...

Use of habitat odour by host-seeking insects.

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Webster, Ben; Cardé, Ring T

2017-05-01

Locating suitable feeding or oviposition sites is essential for insect survival. Understanding how insects achieve this is crucial, not only for understanding the ecology and evolution of insect-host interactions, but also for the development of sustainable pest-control strategies that exploit insects' host-seeking behaviours. Volatile chemical cues are used by foraging insects to locate and recognise potential hosts but in nature these resources usually are patchily distributed, making chance encounters with host odour plumes rare over distances greater than tens of metres. The majority of studies on insect host-seeking have focussed on short-range orientation to easily detectable cues and it is only recently that we have begun to understand how insects overcome this challenge. Recent advances show that insects from a wide range of feeding guilds make use of 'habitat cues', volatile chemical cues released over a relatively large area that indicate a locale where more specific host cues are most likely to be found. Habitat cues differ from host cues in that they tend to be released in larger quantities, are more easily detectable over longer distances, and may lack specificity, yet provide an effective way for insects to maximise their chances of subsequently encountering specific host cues. This review brings together recent advances in this area, discussing key examples and similarities in strategies used by haematophagous insects, soil-dwelling insects and insects that forage around plants. We also propose and provide evidence for a new theory that general and non-host plant volatiles can be used by foraging herbivores to locate patches of vegetation at a distance in the absence of more specific host cues, explaining some of the many discrepancies between laboratory and field trials that attempt to make use of plant-derived repellents for controlling insect pests. © 2016 Cambridge Philosophical Society.

Fresh, dried or smoked? repellent properties of volatiles emitted from ethnomedicinal plant leaves against malaria and yellow fever vectors in Ethiopia

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Dube Fitsum

2011-12-01

Full Text Available Abstract Background In the search for plant-based mosquito repellents, volatile emanations were investigated from five plant species, Corymbia citriodora, Ocimum suave, Ocimum lamiifolium, Olea europaea and Ostostegia integrifolia, traditionally used in Ethiopia as protection against mosquitoes. Methods The behaviour of two mosquitoes, the malaria vector Anopheles arabiensis and the arbovirus vector Aedes aegypti, was assessed towards volatiles collected from the headspace of fresh and dried leaves, and the smoke from burning the dried leaves in a two-choice landing bioassay and in the background of human odour. Results Volatile extracts from the smoke of burning dried leaves were found to be more repellent than those from fresh leaves, which in turn were more repellent to mosquitoes than volatiles from dried leaves. Of all smoke and fresh volatile extracts, those from Co. citriodora (52-76% and Oc. suave (58-68% were found to be the most repellent, Os. integrifolia (29-56% to be intermediate while Ol. europaea (23-40% and Os. integrifolia (19-37% were the least repellent. One volatile present in each of the fresh leaf extracts of Co. citriodora, Oc. suave and Os. integrifolia was ß-ocimene. The levels of ß-ocimene reflected the mosquito repellent activity of these three fresh leaf extracts. Female host-seeking mosquitoes responded dose-dependently to ß-ocimene, both physiologically and behaviourally, with a maximal behavioural repulsion at 14% ß-ocimene. ß-ocimene (14% repels mosquitoes in our 6-minute landing assays comparable to the synthetic insect repellent N,N-diethyl-m-toluamide (10% DEET. Conclusions Volatiles in the smoke of burning as well as fresh leaves of Co. citriodora and Oc. suave have significant repellent properties against host seeking An. arabiensis and Ae. aegypti mosquitoes. ß-ocimene, present in the fresh leaf headspace of Co. citriodora, Oc. suave and Os. integrifolia, is a significantly effective volatile mosquito

Microsporidiosis (Microsporidia: Culicosporidae) alters blood-feeding responses and DEET repellency in Aedes aegypti (Diptera: Culicidae).

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Barnard, Donald R; Xue, Rui-De; Rotstein, Margaret A; Becnel, James J

2007-11-01

Infection of Aedes aegypti (L.) (Diptera: Culicidae) with Edhazardia aedis (Microsporidia: Culicosporidae) reduced mean human host attraction and landing/probing rates in female mosquitoes by 53 and 62%, respectively, compared with rates in microsporidia-free females. Infection with E. aedis reduced the average weight of unfed female mosquitoes by 4%, caused them to imbibe 23% less blood, and to lay 30% fewer eggs than healthy females. In contrast, E. aedis-infected mosquitoes required 20% more time (>1 h) than healthy females to bite skin treated with 15% DEET. Statistically significant morbidity in E. aedis-infected females was indicated by reductions in host attraction and landing/probing responses, the mass of unfed and blood-engorged females, and fecundity, and by increased DEET repellency.

Exotic reptile bites.

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Kelsey, J; Ehrlich, M; Henderson, S O

1997-09-01

Reptiles are a growing part of the exotic pet trade, and reptile bites have been considered innocuous in the emergency medicine literature. Two cases are reported of reptile bites, one from a green iguana and the other from a reticulated python. The treatment concerns associated with reptile bites are discussed.

Repellent Activity of Botanical Oils against Asian Citrus Psyllid, Diaphorina citri (Hemiptera: Liviidae).

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Kuhns, Emily H; Martini, Xavier; Hoyte, Angel; Stelinski, Lukasz L

2016-07-14

The Asian citrus psyllid, Diaphorina citri Kuwayama, is the insect vector of the pathogen causing huanglongbing. We selected three botanical oils to evaluate behavioral activity against D. citri. In laboratory olfactometer assays, fir oil was repellent to D. citri females, while litsea and citronella oils elicited no response from D. citri females. In choice settling experiments, D. citri settled almost completely on control plants rather than on plants treated with fir oil at a 9.5 mg/day release rate. Therefore, we conducted field trials to determine if fir oil reduced D. citri densities in citrus groves. We found no repellency of D. citri from sweet orange resets that were treated with fir oil dispensers releasing 10.4 g/day/tree as compared with control plots. However, we found a two-week decrease in populations of D. citri as compared with controls when the deployment rate of these dispensers was doubled. Our results suggest that treatment of citrus with fir oil may have limited activity as a stand-alone management tool for D. citri and would require integration with other management practices.

Entomologic evaluation of insect hypersensitivity in horses.

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Greiner, E C

1995-04-01

Potential methods of incriminating insects as the cause of insect hypersensitivity are presented. A listing of the biting midges known to attack horses in North America is presented also. An example of how species may be determined to be the cause of the hypersensitivity is given using data from a recent study in Florida. Light trap collections indicated the temporal and geographic distribution of potential contributing species and collections made by vacuuming horses further delineated species by proving they feed on horses and the correct locations on the horses to match lesion distribution. Culicoides hypersensitivity in horses in Florida seems to be caused by a series of species active and feeding on the horses at different times of the year.

Larvicidal, Repellent and Irritant Potential of the Seed-derived Essential oil of Apium graveolens against Dengue Vector, Aedes aegypti L. (Diptera: Culicidae

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Sarita eKumar

2014-09-01

Full Text Available Aedes aegypti L., the primary carrier for viruses causing dengue, chikungunya and yellow fever is widespread over large areas of the tropics and subtropics. Keeping in view the adverse effects of chemical insecticides-based intervention measures; the eco-friendly, bio-degradable essential oil extracted from the seeds of celery, Apium graveolens; was investigated for anti-mosquito potential against Ae. aegypti. Evaluation of larvicidal potential of celery seed oil against early fourth instars of Ae. aegypti resulted in LC50 and LC90 values of 16.10 ppm and 29.08 ppm, respectively, after an exposure to 24 h; the toxic effect of the oil increasing by 1.2 fold with an LC50 value of 13.22 ppm after an exposure to 48h. Interestingly, the seed oil did not cause rapid mortality, suggesting a delayed type of larval killing effect. The remarkable finding of the present study was effective repellency of the essential oil leading to 100% protection till 165 min as compared to control that did not show any repellency against mosquitoes. Only 1 bite was recorded in the 165th minute after which only 2 bites were scored until 180 min of exposure of the oil to the adult mosquitoes. An exciting observation was the knocked-down of mosquitoes caused by the exposure to 10% oil-impregnated papers. The exposure to 1% oil resulted in first flight only after 4 sec and a total of 63.66 average flights during 15 min exposure revealing the relative irritability of 26.97.The qualitative phytochemical study of the oil showed the presence of terpenoids, lactones and flavonoids as the major constituents suggesting their possible role in the toxicity. Present investigations proved celery seed essential oil to be an efficient larvicide and repellent against dengue vector. Further studies are needed to identify the active principles involved, their mode of action, formulated preparations for enhancing potency and stability, toxicity and effects on non-target organisms and the

[Mammal bite management].

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Contreras-Marín, Misael; Sandoval-Rodríguez, Jorge Issac; García-Ramírez, Raúl; Morales-Yépez, Héctor Adolfo

Animal bites are a major public health problem, it is estimated that 2% of the population is bitten each year. Most bites are by dogs and the risk factors include young children, men, certain breeds of dogs and untrained dogs. The risk of infection after bites differs between animal species and depends on the animal teeth and oral flora. Animal bites are still a major cause of morbidity in patients of all ages and have caused several preventable childhood deaths. These wounds often become infected. If the wound requires it, early surgical evaluation must be performed. The use of antibiotics is only recommended for high risk bite wounds. Copyright © 2016 Academia Mexicana de Cirugía A.C. Publicado por Masson Doyma México S.A. All rights reserved.

Identification of Repellent and Insecticidal Constituents from Artemisia mongolica Essential Oil against Lasioderma serricorne

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Chunxue You

2015-01-01

Full Text Available The aims of this research were to determine the chemical composition and insecticidal and repellent activities of the Artemisia mongolica essential oil against Lasioderma serricorne and to isolate active constituents from the essential oil. The essential oil of A. mongolica was obtained by hydrodistillation and 36 components were identified with GC-MS. Eucalyptol (39.88%, (S-cis-verbenol (14.93%, 4-terpineol (7.20%, (−-camphor (6.02%, and α-terpineol (4.20% were found to be major components. With a further isolation process, five constituents obtained from the essential oil were identified as eucalyptol, verbenol, 4-terpineol, camphor, and α-terpineol. In the progress of assay, it showed that L. serricorne adults had different sensitivities to the crude essential oil and isolated constituents. 4-Terpineol exhibited strongest contact activity against L. serricorne, showing the LD50 value of 8.62 μg/adult. Moreover, camphor and α-terpineol showed stronger fumigant activity (LC50=2.91 and 3.27 mg/L air, resp. against L. serricorne than crude essential oil and other constituents. In addition, the essential oil, eucalyptol, verbenol, and α-terpineol showed comparable repellency against L. serricorne adults. The results indicate that the essential oil and isolated compounds have potential to provide more efficient and safer natural insecticides or repellents for control of insects in food and Chinese medicinal materials preservation.

Bioactivity and chemical constituents of the essential oil from Dendranthema indicum (L.) Des Moul. against two stored insects.

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Zhang, Wen-Juan; You, Chun-Xue; Yang, Kai; Wang, Ying; Su, Yang; Geng, Zhu-Feng; Du, Shu-Shan; Wang, Cheng-Fang; Deng, Zhi-Wei; Wang, Yong-Yan

2015-01-01

Dendranthema indicum (L.) Des Moul. is a perennial herb commonly used as a traditional Chinese medicine for a long time. In this work, we took Dendranthema indicum as a target plant and two stored insects which include Tribolium castaneum and Stegobium paniceum adults as target insects. Essential oil obtained from Dendranthema indicum was analyzed by gas chromatography-mass spectrometry (GC-MS). A total of 31 components representing 92.44% of the oil were identified and the main compounds were found to be chamazulene (15.93%), β-caryophyllene (13.78%), germacrene D (9.11%), and b-cis-farnesene (6.59%). With a further isolation, three constituents were obtained from the essential oil and identified as chamazulene, β-caryophyllene and eucalyptol. Significantly, in the progress of assay, it showed that the essential oil and chamazulene exhibited stronger insecticidal and repellent activities against Stegobium paniceum than Tribolium castaneum. The results indicate that additional to its traditional use as Chinese medicinal herb, the essential oil of Dendranthema indicum aerial parts and isolated compounds have potential to be developed into natural insecticides or repellents for control of insects in stored grains.

Animal Bites of the Hand

Science.gov (United States)

... Therapist? Media Find a Hand Surgeon Home Anatomy Animal Bites Email to a friend * required fields From * ... key to prevent problems from a bite. CAUSES Animal Bites Millions of animal bites occur in the ...

Papular dermatitis induced in guinea pigs by the biting midge Culicoides sonorensis (Diptera: Ceratopogonidae).

Science.gov (United States)

O'Toole, D; Pérez de León, A A; Hearne, C; McHolland, L; Yun, L; Tabachnick, W

2003-01-01

Histological, ultrastructural, and virological examinations were performed on abdominal skin from guinea pigs after a blood meal by colony-bred biting midges, Culicoides sonorensis. Small, superficial, cutaneous, crateriform ulcers with necrosis of superficial dermis developed at feeding sites and healed within 24-48 hours. Animals developed nonpruritic erythematous papules 5 days after feeding that persisted until the study ended at 12 days after feeding. Papules corresponded histologically to foci of epidermal hyperplasia and superficial interstitial dermatitis with intraepidermal micropustules and scattered intraepidermal polykaryons. The principal ultrastructural changes were spongiosis in germinal epithelium and neutrophilic-histiocytic exocytosis. No viral agents or broken mouthparts were identified in lesions. The dermatitis may represent a host reaction to persisting insect salivary secretion and should be considered as an additional consequence of blood feeding in future studies involving biting midges.

Spider Bites (For Parents)

Science.gov (United States)

... Videos for Educators Search English Español First Aid: Spider Bites KidsHealth / For Parents / First Aid: Spider Bites ... rare. Signs and Symptoms Of a brown recluse spider bite: red blister in the center with surrounding ...

New roles for cis-jasmone as an insect semiochemical and in plant defense.

Science.gov (United States)

Birkett, M A; Campbell, C A; Chamberlain, K; Guerrieri, E; Hick, A J; Martin, J L; Matthes, M; Napier, J A; Pettersson, J; Pickett, J A; Poppy, G M; Pow, E M; Pye, B J; Smart, L E; Wadhams, G H; Wadhams, L J; Woodcock, C M

2000-08-01

cis-jasmone, or (Z)-jasmone, is well known as a component of plant volatiles, and its release can be induced by damage, for example during insect herbivory. Using the olfactory system of the lettuce aphid to investigate volatiles from plants avoided by this insect, (Z)-jasmone was found to be electrophysiologically active and also to be repellent in laboratory choice tests. In field studies, repellency from traps was demonstrated for the damson-hop aphid, and with cereal aphids numbers were reduced in plots of winter wheat treated with (Z)-jasmone. In contrast, attractant activity was found in laboratory and wind tunnel tests for insects acting antagonistically to aphids, namely the seven-spot ladybird and an aphid parasitoid. When applied in the vapor phase to intact bean plants, (Z)-jasmone induced the production of volatile compounds, including the monoterpene (E)-beta-ocimene, which affect plant defense, for example by stimulating the activity of parasitic insects. These plants were more attractive to the aphid parasitoid in the wind tunnel when tested 48 h after exposure to (Z)-jasmone had ceased. This possible signaling role of (Z)-jasmone is qualitatively different from that of the biosynthetically related methyl jasmonate and gives a long-lasting effect after removal of the stimulus. Differential display was used to compare mRNA populations in bean leaves exposed to the vapor of (Z)-jasmone and methyl jasmonate. One differentially displayed fragment was cloned and shown by Northern blotting to be up-regulated in leaf tissue by (Z)-jasmone. This sequence was identified by homology as being derived from a gene encoding an alpha-tubulin isoform.

The influence of bite size and multiple bites on oral texture sensations

NARCIS (Netherlands)

Wijk, de R.A.; Engelen, L.; Prinz, J.F.; Weenen, H.

2003-01-01

The influence of bite size on sensory mouth- and afterfeel sensations was explored in two studies in which single bites of vanilla custard desserts were varied from 2 to 11 ml (study 1) and in which series of five bites of two different custard desserts were presented consecutively (study 2). In

Protection Ability Comparison of Several Mosquito Repellent Lotion Incorporated with Essential Oils of Mosquito Repellent Plants

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Pramono Putro Utomo

2014-12-01

Full Text Available Most mosquito repellent lotions available on the market today contain the active ingredient diethyltoluamide (DEET which is very harmful to the skin. Natural mosquito repellent research using various essential oils (geranium oil, lemon oil, citronella oil and lavender oil as the active ingredient and the addition of aloe vera gel as a moisturizer has been done on a laboratory scale. The purpose of this study was to compare the protection ability of the mosquito repellent plants in Indonesia. The results showed that geranium oil, lemongrass oil, lavender oil and lemon oil could act as mosquito repellent. Best lotion formula all containing 15% essential oils have the effectiveness above 50% until the sixth hour were geranium oil, citronella oil and lavender oil while lemon oil only giving effectiveness above 50% until the second hour.

On-line solid phase extraction-liquid chromatography-tandem mass spectrometry for insect repellent residue analysis in surface waters using atmospheric pressure photoionization.

Science.gov (United States)

Molins-Delgado, Daniel; García-Sillero, Daniel; Díaz-Cruz, M Silvia; Barceló, Damià

2018-04-06

Insect repellents (IRs) are a group of organic chemicals whose function is to prevent the ability of insects of landing in a surface. These compounds have been found in the environment and may pose a risk to non-target organisms. In this study, an on-line solid phase extraction - high performance liquid chromatography-tandem mass spectrometry multiresidue method was developed using an atmospheric photoionization source (SPE-HPLC-(APPI)-MS/MS). The use of the APPI as an alternative ionization technique to electrospray (ESI) and atmospheric pressure chemical ionization (APCI) allowed expanding the range of analytical techniques suitable for the analysis of IRs, so far relied in gas chromatography. High sensitivity and precision was reached with method limits of quantification between 0.2 and 4.6 ng l -1 and interday and intraday precision equal or below 15%. The validated method was applied to the study of surface water samples from three European river basins with different flow regime (Adige River in Italy, Sava River in the Balkans, and Evrotas River in Greece). The results showed that two IRs (DEET and Bayrepel) were ubiquitous in the Sava and Evrotas basins, reaching concentrations as high as 105 μg l -1 of Bayrepel in the Sava River, and 5 μg l -1 of DEET in the Evrotas River. Densely populated areas and effluent waste waters are pointed out as the responsible for this pollution. In the alpine river Adige, only three samples showed low levels of IRs (6.01-37.8 ng l -1 ). The concentrations measured were used to perform an environmental risk assessment based on the hazard quotients (HQs) estimation approach by using the chronic and acute eco-toxicity data available. The results revealed that despite the high frequency and eventually high concentrations of these IRs determined in the three basins, only few sites were at risk, with 1 < HQs < 3.3. Copyright © 2018 The Author(s). Published by Elsevier B.V. All rights reserved.

Chemical ecology of insects and tritrophic interactions

International Nuclear Information System (INIS)

Ahmad, F.; Aslam, M.; Razaq, M.

2004-01-01

This paper reviews the chemical ecology of insects to explain the role of semiochemicals in plant-herbivore, herbivore-carnivore and plant-carnivore interactions. The semiochemical, mediating tritrophic interactions may be produced by plants, herbivores or their natural enemies (carnivores). Some semiochemicals attract the herbivores and carnivores and mediate interaction among them, while on the other hand some repel them. The semiochemicals are used by heribivores, parasites and predators as cues to locate food, host or prey. The same chemicals are also used for defensive purpose by some herbivores against their natural enemies as they are sequestered through their bodies. (author)

Insecticidal and Repellant Activities of Four indigenous medicinal Plants Against Stored Grain Pest, Tribolium castaneum (Herbst (Coleoptera:Tenebrionidae

Directory of Open Access Journals (Sweden)

S.R.Pugazhvendan

2012-05-01

Full Text Available Objective: The present investigation was aimed to assess the impact of four indigenous plants for their insecticidal and repellent activity against Tribolium castaneum (Herbst, a stored grain pest and they were tested in the laboratory. Methods: Four widely distributed plants (Artemisia vulgaris, Sphaeranthus indicus, Tephrosia purpurea, and Prosopis juliflora were sequentially extracted with increasing polarity of organic solvents such as, hexane, chloroform and ethyl acetate were evaluated for their insecticidal and repellent activities against Tribolium castaneum by adapting the standard protocol in in vitro. Results: Data pertaining to the present investigation clearly revealed that the percentage of mortality was maximum in(72 hr 58% hexane extract of A. vulgaris, chloroform extract (72 hr 34% of S. indicus, and ethyl acetate extract (72 hr 52% of T. purpurea. Repellant activities of plant extracts were tested against T. castaneum, repellent activity was maximum in hexane extract of P. fuliflora, ( EPI value for P. fuliflora in 2.5% was – 0.11 and – 0.33 at 1hr and 6 hr respectively chloroform extract of T. purpurea (2.5% was -0.17 at 6 hr and ethyl acetate extract of S. indicus (2.5% was -0.65 at 6 hr against T. castaneum. Conclusions: The present work for botanical products to control the insect pest of stored grain Tribolium castaneum (Herbst.These results suggest the presence of actives toxic substances acting after consumption or topical application.

The influence of bite size and multiple bites on oral texture sensations

NARCIS (Netherlands)

Wijk, R.A. de; Engelen, L.; Prinz, J.F.; Weenen, H.

2003-01-01

The influence of bite size on sensory mouthfeel and afterfeel sensations was explored in two studies in which single bites of vanilla custard desserts were varied from 2 to 11 mL (study 1) and in which series of five bites of two different custard desserts were presented consecutively (study 2). In

Soil water repellency at old crude oil spill sites

International Nuclear Information System (INIS)

Roy, J.L.

1999-08-01

This thesis presents the current state of knowledge regarding the cause of soil water repellency and characterizes disaggregated nonwettable surface soils found at old crude oil spill sites. Pollution-induced water repellency generally develops following prolonged exposures of soil to liquid- or vapour-phase petroleum hydrocarbons. The condition varies significantly in terms of severity and persistence. Soil water repellency retards plant growth and disturbs the hydrological balance of ecosystems. Disaggregated water-repellent soils are also very susceptible to dispersal by erosion, posing a threat to the productivity of surrounding soils. The author described the probable causes of soil water repellency under the following three main themes: (1) accumulation of hydrophobic organic material in soil, (2) redistribution and re-organisation of this material in soil, and (3) stabilisation of the hydrophobic organic material. This final process is necessary to ensure persistence of induced water repellency symptoms. Petroleum residues as water-repellent substances in weathered nonwettable oil-contaminated soils were also discussed and a hypothesis about soil water repellency was presented which deals with flexible conformation in organic matter coatings. Processes leading to the development of soil water repellency following crude oil contamination were also described. It was determined that soil water repellency is a function of the packing density and the chain conformation of amphiphilic organic molecules in the outermost layer of soil organic matter coatings. This research suggests that the fractional coverage of alkyl chains on soil particle surfaces determines the degree of water repellency that is displayed by soil. It was shown that prompt remediation of some oil-contaminated plots can effectively prevent the development of soil water repellency. 4 refs., 32 tabs., 22 figs., 5 appendices

Effect of ebastine on mosquito bites.

Science.gov (United States)

Reunala, T; Brummer-Korvenkontio, H; Petman, L; Palosuo, T; Sarna, S

1997-07-01

Mosquito bites usually cause wealing and delayed bite papules. Cetirizine decreases wealing, bite papules and pruritus but the effect of other antihistamines on mosquito bites is unknown. We studied the effect of ebastine in 30 mosquito bite-sensitive adult subjects. Ebastine 10 mg or 20 mg and placebo were given for 4 days in a cross-over fashion. Aedes aegypti bites were given on forearms. The size of the bite lesions and pruritus (visual analogue score) were measured at 15 min, 2, 6, and 24 h after the bites. Twenty-five subjects were evaluable in the study. At 15 min ebastine decreased significantly the size of the bite lesion (p = 0.0017) and pruritus (ptime points were compiled the size of the bite lesion and pruritus score decreased significantly. Sedation occurred during ebastine treatment in 6 (21%) and during placebo treatment in 2 (7%) subjects. The present results show that prophylactically given ebastine is effective against immediate mosquito bite symptoms.

GC×GC-TOFMS Analysis of Essential Oils Composition from Leaves, Twigs and Seeds of Cinnamomum camphora L. Presl and Their Insecticidal and Repellent Activities.

Science.gov (United States)

Jiang, Hao; Wang, Jin; Song, Li; Cao, Xianshuang; Yao, Xi; Tang, Feng; Yue, Yongde

2016-03-28

Interest in essential oils with pesticidal activity against insects and pests is growing. In this study, essential oils from different parts (leaves, twigs and seeds) of Cinnamomum camphora L. Presl were investigated for their chemical composition, and insecticidal and repellent activities against the cotton aphid. The essential oils, obtained by hydrodistillation, were analyzed by GC×GC-TOFMS. A total of 96 components were identified in the essential oils and the main constituents found in the leaves and twigs were camphor, eucalyptol, linalool and 3,7-dimethyl-1,3,7-octatriene. The major components found in the seeds were eucalyptol (20.90%), methyleugenol (19.98%), linalool (14.66%) and camphor (5.5%). In the contact toxicity assay, the three essential oils of leaves, twigs and seeds exhibited a strong insecticidal activity against cotton aphids with LC50 values of 245.79, 274.99 and 146.78 mg/L (after 48 h of treatment), respectively. In the repellent assay, the highest repellent rate (89.86%) was found in the seed essential oil at the concentration of 20 μL/mL after 24 h of treatment. Linalool was found to be a significant contributor to the insecticidal and repellent activities. The results indicate that the essential oils of C. camphora might have the potential to be developed into a natural insecticide or repellent for controlling cotton aphids.

Determinants of abundance and effects of blood-sucking flying insects in the nest of a hole-nesting bird.

Science.gov (United States)

Tomás, Gustavo; Merino, Santiago; Martínez-de la Puente, Josué; Moreno, Juan; Morales, Judith; Lobato, Elisa

2008-05-01

Compared to non-flying nest-dwelling ectoparasites, the biology of most species of flying ectoparasites and its potential impact on avian hosts is poorly known and rarely, if ever, reported. In this study we explore for the first time the factors that may affect biting midge (Diptera: Ceratopogonidae) and black fly (Diptera: Simuliidae) abundances in the nest cavity of a bird, the hole-nesting blue tit Cyanistes caeruleus, and report their effects on adults and nestlings during reproduction. The abundance of biting midges was positively associated with nest mass, parental provisioning effort and abundance of blowflies and black flies, while negatively associated with nestling condition. Furthermore, a medication treatment to reduce blood parasitaemias in adult birds revealed that biting midges were more abundant in nests of females whose blood parasitaemias were experimentally reduced. This finding would be in accordance with these insect vectors attacking preferentially uninfected or less infected hosts to increase their own survival. The abundance of black flies in the population was lower than that of biting midges and increased in nests with later hatching dates. No significant effect of black fly abundance on adult or nestling condition was detected. Blood-sucking flying insects may impose specific, particular selection pressures on their hosts and more research is needed to better understand these host-parasite associations.

Repellent Activity of Botanical Oils against Asian Citrus Psyllid, Diaphorina citri (Hemiptera: Liviidae

Directory of Open Access Journals (Sweden)

Emily H. Kuhns

2016-07-01

Full Text Available The Asian citrus psyllid, Diaphorina citri Kuwayama, is the insect vector of the pathogen causing huanglongbing. We selected three botanical oils to evaluate behavioral activity against D. citri. In laboratory olfactometer assays, fir oil was repellent to D. citri females, while litsea and citronella oils elicited no response from D. citri females. In choice settling experiments, D. citri settled almost completely on control plants rather than on plants treated with fir oil at a 9.5 mg/day release rate. Therefore, we conducted field trials to determine if fir oil reduced D. citri densities in citrus groves. We found no repellency of D. citri from sweet orange resets that were treated with fir oil dispensers releasing 10.4 g/day/tree as compared with control plots. However, we found a two-week decrease in populations of D. citri as compared with controls when the deployment rate of these dispensers was doubled. Our results suggest that treatment of citrus with fir oil may have limited activity as a stand-alone management tool for D. citri and would require integration with other management practices.

Evaluation of Ultrasonic Waves System in Repellency of Red Beetle of Flour (Tribolium castaneum Herbs

Directory of Open Access Journals (Sweden)

P. Ahmadi Moghaddam

2016-06-01

Full Text Available Introduction: Increase of world population, lack of food sources, and need for food security, protection of agricultural products against losses, drought, pests, and diseases, all seems to be necessary more than ever. During the years, grains have been the main food of humans, especially wheat, barley, rice, and corn. So production and storage of these products is important for societies. One of the main problems in this field is protecting the grains in stores until consuming or planting them again. Annually, over hundreds of millions tons of grains are lost by pests present in stores and not observing the scientific principles of storing. Control of insects and pests during storage as a destructive factor of stored products by harmless methods is necessary. There are restrictions in use of chemically control methods against pests in stores. Therefore in recent decades, physically control methods have attracted a lot of attentions. The purpose of using physically control methods is eliminating pests with minimum destructive effect on the environment. These methods directly affect on pests or change their living situations and create an unsafe environment for them. One of the tools that indirectly affect pests is ultrasonic waves. Ultrasonic waves are mechanical waves which can properly penetrate in air and porous areas. These waves are completely safe for the environment and cause no damage to the environment. Ultrasonic waves as new safe strategy in insect control can prepare unsafe areas for annoying insects and agricultural pests. The main characteristics of ultrasonic waves are safe for humans and environment. Materials and Methods: In this study, experiments were carried out to assess the repellent impact of ultrasonic waves on one important storage pest, red flour beetle (Tribolium castaneum Herbs. The system, which produces ultrasonic waves, includes distributor of ultrasonic waves, power supply, central processor, oscillator, display

Velocity correlations in laboratory insect swarms

Science.gov (United States)

Ni, R.; Ouellette, N. T.

2015-12-01

In contrast to animal groups such as bird flocks or migratory herds that display net, directed motion, insect swarms do not possess global order. Without such order, it is difficult to define and characterize the transition to collective behavior in swarms; nevertheless, visual observation of swarms strongly suggests that swarming insects do behave collectively. It has recently been suggested that correlation rather than order is the hallmark of emergent collective behavior. Here, we report measurements of spatial velocity correlation functions in laboratory mating swarms of the non-biting midge Chironomus riparius. Although we find some correlation at short distances, our swarms are in general only weakly correlated, in contrast to what has been observed in field studies. Our results hint at the potentially important role of environmental conditions on collective behavior, and suggest that general indicators of the collective nature of swarming are still needed.

Human bites (image)

Science.gov (United States)

Human bites present a high risk of infection. Besides the bacteria which can cause infection, there is ... the wound extends below the skin. Anytime a human bite has broken the skin, seek medical attention.

Limitation of using synthetic human odours to test mosquito repellents

Directory of Open Access Journals (Sweden)

Mbeyela Edgar

2009-07-01

Full Text Available Abstract Background Gold-standard tests of mosquito repellents involve exposing human volunteers to host-seeking mosquitoes, to assess the protective efficacy of the repellents. These techniques are not exposure-free and cannot be performed prior to toxicological evaluation. It is postulated that synthetic lures could provide a useful assay that mimics in-vivo conditions for use in high-throughput screening for mosquito repellents. Methods This paper reports on a semi-field evaluation of repellents using a synthetic blend of human derived attractants for the malaria vector, Anopheles gambiae sensu stricto Different concentrations of known repellents, N, N diethyl-3-methylbenzamide (deet and Para-methane-3, 8, diol (PMD were added into traps baited with the synthetic blend, and resulting changes in mosquito catches were measured. Results All test concentrations of deet (0.001% to 100% reduced the attractiveness of the synthetic blend. However, PMD was repellent only at 0.25%. Above this concentration, it significantly increased the attractiveness of the blend. There was no relationship between the repellent concentrations and the change in mosquito catches when either deet (r2 = 0.033, P = 0.302 or PMD (r2 = 0.020, P = 0.578 was used. Conclusion It is concluded that while some repellents may reduce the attractiveness of synthetic human odours, others may instead increase their attractiveness. Such inconsistencies indicate that even though the synthetic attractants may provide exposure-free and consistent test media for repellents, careful selection and multiple-repellent tests are necessary to ascertain their suitability for use in repellent screening. The synthetic odour blend tested here is not yet sufficiently refined to serve as replacement for humans in repellent testing, but may be developed further and evaluated in different formats for exposure free repellent testing purposes.

Water repellent soils: a state-of-the-art

Science.gov (United States)

Leonard F. DeBano

1981-01-01

Water repellency in soils was first described by Schreiner and Shorey (1910), who found that some soils in California could not be wetted and thereby were not suitable for agriculture. Waxy organic substances were responsible for the water repellency. Other studies in the early 1900's on the fairy ring phenomenon suggested that water repellency could be caused by...

How to Stop Biting Your Nails

Medline Plus

Full Text Available ... gloves to prevent biting. Replace the nail-biting habit with a good habit: When you feel like biting your nails, try ... recommend taking a gradual approach to break the habit. Try to stop biting one set of nails, ...

Population suppression in support of the sterile insect technique

International Nuclear Information System (INIS)

Mangan, R.L.

2005-01-01

Suppression or eradication of insect pest populations by the release of sterile insects is often dependent on supplementary methods of pest reduction to levels where the target pest population can be overflooded with sterile insects. Population suppression activities take place in advance of, or coincide with, the production of sterile insects. Supplementary methods to remove breeding opportunities, or management methods that prevent access of pests to the hosts, may reduce the population or prevent damage. Insecticides have been used widely in direct applications or applied as baits, in traps, or on specific sites where the pest makes contact or reproduces. As sterile insect release does not kill the pest, adult biting pests or fertile mated females of the pests will continue to attack hosts after the release of sterile insects. Thus supplementary pest suppression programmes and quarantine measures are essential to prevent damage or the spread of disease. Eradication or effective pest management requires that the entire population of the pest be treated, or that the programme apply immigration barriers. When supplementary pest control activities benefit the human population in areas being treated, such as in mosquito or screwworm eradication programmes, these activities are usually acceptable to the public, but when the public receives no direct benefit from supplementary control activities such as in fruit fly programmes, social resistance may develop. (author)

A Fat strange Repeller

Institute of Scientific and Technical Information of China (English)

申影; 何阅; 姜玉梅; 何大韧

2004-01-01

This article reports an observation on a fat strange repeller, which appears after a characteristic crisis observed in a kicked rotor subjected to a piecewise continuous force field. The discontinuity border in the definition range of the two-dimensional mapping, which describes the system, oscillates as the discrete time develops. At a threshold of a control parameter a fat chaotic attractor suddenly transfers to a fat transient set. The strange repeller, which appears after the crisis, is also a fat fractal. This is the reason why super-transience happens

Topical Hazard Evaluation Program of Candidate Insect Repellent AI3- 39053a

Science.gov (United States)

1987-05-01

StudyNo. 75-51-O 71-R7 Mnay 19R71 12 PERSONAL AUTHOR(S) William T. Huebsam, SGT, U.S.A.; Maurice H. Weeks 1I8. TYPE Of REPORT 13b TIME COVERED 114...ARMY u.S. AUT ENVIVIf[NNIAL HYGINE AMIdT ASCROELN PROVING GROUND. MARYLAND M1蚉 HSHB-MO-T TOPICAL HAZARD EVALUATION PROGRAM OF CANDIDATE INSECT

Aquatic Insects of New York Salt Marsh Associated with Mosquito Larval Habitat and their Potential Utility as Bioindicators

OpenAIRE

Rochlin, Ilia; Dempsey, Mary E.; Iwanejko, Tom; Ninivaggi, Dominick V.

2011-01-01

The aquatic insect fauna of salt marshes is poorly characterized, with the possible exception of biting Diptera. Aquatic insects play a vital role in salt marsh ecology, and have great potential importance as biological indicators for assessing marsh health. In addition, they may be impacted by measures to control mosquitoes such as changes to the marsh habitat, altered hydrology, or the application of pesticides. Given these concerns, the goals of this study were to conduct the first taxonom...

Dimension of non-conformal repellers: a survey

International Nuclear Information System (INIS)

Chen, Jianyu; Pesin, Yakov

2010-01-01

This paper is a survey of recent results on the dimension of repellers for expanding maps and limit sets for iterated function systems. While the case of conformal repellers is well understood, the study of non-conformal repellers is in its early stages though a number of interesting phenomena have been discovered, some remarkable results obtained and several interesting examples constructed. We will describe contemporary state of the art in the area with emphasis on some new emerging ideas and open problems. (invited article)

Moisture variability resulting from water repellency in Dutch soils

NARCIS (Netherlands)

Dekker, L.W.

1998-01-01

The present study suggests that many soils in the Netherlands, in natural as well as in agricultural areas, may be water repellent to some degree, challenging the common perception that soil water repellency is only an interesting aberration. When dry, water repellent soils resist or retard

Evaporation and skin penetration characteristics of mosquito repellent formulations

International Nuclear Information System (INIS)

Reifenrath, W.G.; Hawkins, G.S.; Kurtz, M.S.

1989-01-01

Formulations of the mosquito repellent N,N-diethyl-3-methylbenzamide (deet) in combination with a variety of additives were developed to control repellent evaporation and percutaneous penetration. Deet was also formulated with the repellent dimethyl phthalate to study the interaction of the two compounds on the skin. The evaporation and penetration processes were evaluated on whole and split-thickness pig skin using radiolabeled repellents with an in vitro apparatus. Under essentially still air and air flow conditions, one of the deet formulations resulted in significantly reduced total evaporation and percutaneous penetration of deet as compared to unformulated repellent. When deet and dimethyl phthalate were combined, neither repellent affected the total amount of evaporation and penetration of the other compound. However, initial percutaneous penetration and evaporation rates were slightly less and decayed less rapidly than when both chemicals were tested separately at the same dose. These results indicated a degree of competition of the two compounds for the same avenues of loss

Food aroma affects bite size

Directory of Open Access Journals (Sweden)

de Wijk René A

2012-03-01

Full Text Available Abstract Background To evaluate the effect of food aroma on bite size, a semisolid vanilla custard dessert was delivered repeatedly into the mouth of test subjects using a pump while various concentrations of cream aroma were presented retronasally to the nose. Termination of the pump, which determined bite size, was controlled by the subject via a push button. Over 30 trials with 10 subjects, the custard was presented randomly either without an aroma, or with aromas presented below or near the detection threshold. Results Results for ten subjects (four females and six males, aged between 26 and 50 years, indicated that aroma intensity affected the size of the corresponding bite as well as that of subsequent bites. Higher aroma intensities resulted in significantly smaller sizes. Conclusions These results suggest that bite size control during eating is a highly dynamic process affected by the sensations experienced during the current and previous bites.

Pest repelling properties of ant pheromones

DEFF Research Database (Denmark)

Offenberg, Joachim

2014-01-01

Ants control pests via predation and physical deterrence; however, ant communication is based on chemical cues which may serve as warning signals to potential prey and other intruders. The presence of ant pheromones may, thus, be sufficient to repel pests from ant territories. This mini-review sh......-review shows that four out of five tested ant species deposit pheromones that repel herbivorous prey from their host plants.......Ants control pests via predation and physical deterrence; however, ant communication is based on chemical cues which may serve as warning signals to potential prey and other intruders. The presence of ant pheromones may, thus, be sufficient to repel pests from ant territories. This mini...

Dihydronepetalactones deter feeding activity by mosquitoes, stable flies, and deer ticks.

Science.gov (United States)

Feaster, John E; Scialdone, Mark A; Todd, Robin G; Gonzalez, Yamaira I; Foster, Joseph P; Hallahan, David L

2009-07-01

The essential oil of catmint, Nepeta cataria L., contains nepetalactones, that, on hydrogenation, yield the corresponding dihydronepetalactone (DHN) diastereomers. The DHN diastereomer (4R,4aR,7S,7aS)-4,7-dimethylhexahydrocyclopenta[c]pyran-1(3H)-one, DHN 1) was evaluated as mosquito repellent, as was the mixture of diastereomers {mostly (4S,4aR,7S,7aR)-4,7-dimethylhexahydrocyclopenta[c]pyran-1(3H)-one, DHN 2} present after hydrogenation of catmint oil itself. The repellency of these materials to Aedes aegypti L. and Anopheles albimanus Wiedemann mosquitoes was tested in vitro and found to be comparable to that obtained with the well-known insect repellent active ingredient N,N-diethyl-3-methylbenzamide (DEET). DHN 1 and DHN 2 also repelled the stable fly, Stomoxys calcitrans L., in this study. DHN 1, DHN 2, and p-menthane-3,8-diol (PMD), another natural monoterpenoid repellent, gave comparable levels of repellency against An. albimanus and S. calcitrans. Laboratory testing of DHN 1 and DHN 2 using human subjects with An. albimanus mosquitoes was carried out. Both DHN 1 and DHN 2 at 10% (wt:vol) conferred complete protection from bites for significant periods of time (3.5 and 5 h, respectively), with DHN2 conferring protection statistically equivalent to DEET. The DHN 1 and DHN 2 diastereomers were also efficaceous against black-legged tick (Ixodes scapularis Say) nymphs.

Identification of Repellent and Insecticidal Constituents of the Essential Oil of Artemisia rupestris L. Aerial Parts against Liposcelis bostrychophila Badonnel

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Zhi Long Liu

2013-09-01

Full Text Available The aim of this research was to determine the chemical composition and insecticidal and repellent activity of the essential oil of Artemisia rupestris L. aerial parts against the booklice Liposcelis bostrychophila Badonnel and isolation of insecticidal and repellent constituents from the essential oil. The essential oil of A. rupestris was obtained by hydrodistillation and analyzed by GC-MS. A total of 30 components of the essential oil of A. rupestris was identified and the principal compounds in the essential oil were α-terpinyl acetate (37.18%, spathulenol (10.65%, α-terpineol (10.09%, and linalool (7.56%, followed by 4-terpineol (3.92% and patchoulol (3.05%. Based on bioactivity-guided fractionation, the four active constituents were isolated from the essential oil and identified as α-terpineol, α-terpinyl acetate, 4-terpineol and linalool. The essential oil of A. rupestris exhibited contact toxicity against L. bostrychophila with LD50 value of 414.48 µg/cm2. α-Terpinyl acetate (LD50 = 92.59 µg/cm2 exhibited stronger contact toxicity against booklice than α-terpineol (LD50 = 140.30 µg/cm2, 4-terpineol (LD50 = 211.35 µg/cm2, and linalool (LD50 = 393.16 µg/cm2. The essential oil of A. rupestris (LC50 = 6.67 mg/L air also possessed fumigant toxicity against L. bostrychophila while the four constituents, 4-terpineol, α-terpineol, α-terpinyl acetate and linalool had LC50 values of 0.34, 1.12, 1.26 and 1.96 mg/L air, respectively. α-Terpinol and α-terpinyl acetate showed strong repellency against L. bostrychophila, while linalool and 4-terpinol exhibited weak repellency. The results indicate that the essential oil of A. rupestris aerial parts and its constituent compounds have potential for development into natural insecticides or fumigants as well as repellents for control of insects in stored grains.

prevalence of biting and non-biting flies in relation to species

African Journals Online (AJOL)

USER

support high abundance of biting flies due to the favourable conditions within the forest for breeding, refuge and easy migration of adult females to animal cages to seek for blood meal. Table 1: Abundance of Biting Flies in Relation to Species in the Jos Museum. Zoological Garden. Site. Stomoxys calcitrans. Haematopota.

Longitudinal evaluation of Ocimum and other plants effects on the feeding behavioral response of mosquitoes (Diptera: Culicidae in the field in Tanzania

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Tenu Filemoni

2008-10-01

Full Text Available Abstract Background The use of repellent materials from plants against nuisance insects is common with great potential to compliment existing malaria control programmes and this requires evaluation in the field. Ocimum plant species, Ocimum suave (Willd and O. kilimandscharicum (Guerke materials and their essential oils extracted by steam distillation were evaluated in the field and experimental huts for repellence, exophily and feeding inhibition effects against three mosquito species, Anopheles arabiensis (Patton, An. gambiae ss (Giles and Culex quinquefasciatus (Say. The protective effect of essential oils from Ocimum plants were compared with N, N-diethly-3- methylbenzamide (DEET, a standard synthetic repellent. Also, the protective effect of fumigation by burning of repellent plants; Ocimum suave, Ocimum kilimandscharicum, Azadirachta indica, Eucalyptus globules and Lantana camara were tested in experimental huts and selected local houses. Results In the field, protection by Ocimum plants from mosquito bites was high and there was small variation among different mosquito species. Protection efficiency was 93.4%, 91.98% and 89.75% for An. arabiensis while for Cx. quinquefaciatus it was 91.30%, 88.65% and 90.50% for DEET, Ocimum suave and O. kilimandscharicum respectively. In the experimental hut, deterrence induced by burning of Ocimum and other plants ranged from 73.1.0% to 81.9% for An. arabiensis and 56.5% to 67.8% for Cx. quinquefaciatus, while feeding inhibition was 61.1% to 100% for An. arabiensis and 50% to 100% for Cx. quinquefaciatus. Evaluations under field conditions confirmed high protective efficacy, enhanced feeding inhibition and house entry inhibition (Deterrence. Conclusion This study shows the potential of Ocimum suave and Ocimum kilimandscharicum crude extracts and whole plants of Ocimum suave, Ocimum kilimandscharicum, Azadirachta indica, Eucalyptus globules and Lantana camara for use in protecting against human biting

Bug Bites and Stings

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... can carry other diseases, such as malaria and dengue fever. Spider Bites Most spider bites are minor, ... Clean the area with soap and water, and treat with an antiseptic or antibiotic cream to avoid ...

Funnel-web spider bite

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... page: //medlineplus.gov/ency/article/002844.htm Funnel-web spider bite To use the sharing features on ... the effects of a bite from the funnel-web spider. Male funnel-web spiders are more poisonous ...

Four emerging arboviral diseases in North America: Jamestown Canyon, Powassan, chikungunya, and Zika virus diseases.

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Pastula, Daniel M; Smith, Daniel E; Beckham, J David; Tyler, Kenneth L

2016-06-01

Arthropod-borne viruses, or arboviruses, are viruses that are transmitted through the bites of mosquitoes, ticks, or sandflies. There are numerous arboviruses throughout the world capable of causing human disease spanning different viral families and genera. Recently, Jamestown Canyon, Powassan, chikungunya, and Zika viruses have emerged as increasingly important arboviruses that can cause human disease in North America. Unfortunately, there are currently no proven disease-modifying therapies for these arboviral diseases, so treatment is largely supportive. Given there are also no commercially available vaccines for these four arboviral infections, prevention is the key. To prevent mosquito or tick bites that might result in one of these arboviral diseases, people should wear long-sleeved shirts and pants while outside if feasible, apply insect repellant when going outdoors, using window screens or air conditioning to keep mosquitoes outside, and perform tick checks after being in wooded or brushy outdoor areas.

Effect of the Topical Repellent para-Menthane-3,8-diol on Blood Feeding Behavior and Fecundity of the Dengue Virus Vector Aedes aegypti

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Jugyeong Lee

2018-06-01

Full Text Available Dengue fever is an acute disease caused by the dengue virus and transmitted primarily by the mosquito Aedes aegypti. The current strategy for dengue prevention is vector control including the use of topical repellents to reduce mosquito biting. Although N,N-diethyl-m-methylbenzamide (DEET is the most common active ingredient in topical repellent products, para-menthane-3,8-diol (PMD is also used commercially. Studies have indicated PMD reduced biting by 90–95% for up to 6–8 h, similar to the efficacy of DEET, depending on the testing environment. The purpose of this study was to evaluate the behavioral effects of PMD on Ae. aegypti blood feeding and fecundity to explore the potential impact of PMD on downstream mosquito life-history traits. Two experiments were performed. In both experiments, cohorts of female Ae. aegypti (Belize strain were exposed to 20% PMD or ethanol for 10 min in a closed system and introduced to an artificial membrane feeding system. Following a 30min feed time, mosquitoes of Experiment 1 were killed and weighed as a proxy measure of blood meal, whereas mosquitoes of Experiment 2 were monitored for oviposition, a measure of fecundity. Results showed a statistically significant reduction (p < 0.001 in the percentage of Ae. aegypti that blood-fed when exposed to PMD (38% compared to those non-exposed (49%. No significant difference in fecundity between test populations was indicated. These findings suggest that exposure of Ae. aegypti to 20% PMD may influence the probability of subsequent blood feeding but of those mosquitoes that do blood feed, egg-lay density is not affected. Further studies are warranted to investigate the full range of effects of PMD exposure on other Ae. aegypti life-history traits such as mating, to continue characterizing the potential effects of PMD to impact overall vector population dynamics.

How to Stop Biting Your Nails

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Full Text Available ... your fingers and from your nails to your face and mouth. To help you stop biting your ... re inclined to bite may help solve the problem. Try to gradually stop biting your nails: Some ...

How to Stop Biting Your Nails

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Full Text Available ... skin, hair, and nails Skin dictionary Camp Discovery Good Skin Knowledge lesson plans and activities Video library ... biting. Replace the nail-biting habit with a good habit: When you feel like biting your nails, ...

How to Stop Biting Your Nails

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Full Text Available ... biting can make the skin around your nails feel sore, and it can damage the tissue that ... biting habit with a good habit: When you feel like biting your nails, try playing with a ...

How to Stop Biting Your Nails

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Full Text Available ... this safe, but awful-tasting formula discourages many people from biting their nails. Get regular manicures: Spending ... longer bite any of your nails. For some people, nail biting may be a sign of a ...

Court presentation of bite mark evidence.

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Drinnan, A J; Melton, M J

1985-12-01

The uniqueness of an individual's bite mark is generally accepted. The use of bite mark analysis to identify or exclude those suspected of crimes is now a well established activity in forensic dentistry. Although the techniques for evaluating bite mark evidence are extremely sophisticated, it is important that the courtroom presentation of such evidence should be as simple as possible and be directed towards those who must judge it. Dentists likely to be involved in the courtroom presentation of bite mark evidence should: be certain that their local law enforcement personnel are frequently updated on the techniques to be used for producing the optimum evidence needed to evaluate bite marks; become acquainted with the current techniques of evaluating bite mark evidence and understand their difficulties and pitfalls; meet with the lawyers (prosecution or defence) before a courtroom appearance, briefing them on the significance of the particular findings; prepare clear and easily understandable visual aids to present to the court the techniques used in the analysis and the bases for the conclusion reached; and offer conclusions derived from the bite mark investigation.

Field Method for Testing Repellency of an Icaridin-Containing Skin Lotion against Vespid Wasps

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Jean-Luc Boevé

2016-06-01

Full Text Available Vespid wasps are ecologically beneficial predators of insects but their stings also pose a human health risk. Current control methods based on killing vespids are suboptimal. Here, the repellent effect against Vespula vulgaris of a 20% icaridin skin lotion was evaluated under field conditions. An experimental setup was designed in which six artificial skin pieces (10 × 10 cm were video-recorded for 1 h, to count each min the numbers of flying and feeding vespids. Prior to monitoring, five pieces were successively smeared with 2 mg of cream per cm2, in 30 min intervals, from t = −120 min to 0. The sixth sheet remained untreated to serve as a control. One milliliter of an attractant, fruit jam, was deposited on each of the six surfaces at t = 0. The control surface was free of any flying or feeding vespid during an average period of 25 min, whereas the other five surfaces (treated at t = −120, −90, −60, −30, and 0 min remained vespid-free for 39, 40, 45, 49, and 51 min, respectively. The skin lotion remained significantly active for at least 2 h. The experimental methodology is adjustable and allows the study of repellents against vespids in semi-natural conditions.

Repellents inhibit P450 enzymes in Stegomyia (Aedes aegypti.

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Gloria Isabel Jaramillo Ramirez

Full Text Available The primary defence against mosquitoes and other disease vectors is often the application of a repellent. Despite their common use, the mechanism(s underlying the activity of repellents is not fully understood, with even the mode of action of DEET having been reported to be via different mechanisms; e.g. interference with olfactory receptor neurones or actively detected by olfactory receptor neurones on the antennae or maxillary palps. In this study, we discuss a novel mechanism for repellence, one of P450 inhibition. Thirteen essential oil extracts from Colombian plants were assayed for potency as P450 inhibitors, using a kinetic fluorometric assay, and for repellency using a modified World Health Organisation Pesticide Evaluations Scheme (WHOPES arm-in cage assay with Stegomyia (Aedes aegypti mosquitoes. Bootstrap analysis on the inhibition analysis revealed a significant correlation between P450-inhibition and repellent activity of the oils.

SHORT COMMUNICATION Repellency property of long chain ...

African Journals Online (AJOL)

Repellency property of long chain aliphatic methyl ketones against Anopheles gambiae s.s ... tained from huge diversity of plant species are an important source of safe .... dry and then introduced with the hand covered by a glove in .... citronellal in repelling bees from basil (Oci- ... Journal of American Mosquito Control As-.

EPA-Registered Repellents for Mosquitoes Transmitting Emerging Viral Disease.

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Patel, Radha V; Shaeer, Kristy M; Patel, Pooja; Garmaza, Aleksey; Wiangkham, Kornwalee; Franks, Rachel B; Pane, Olivia; Carris, Nicholas W

2016-12-01

In many parts of the United States, mosquitoes were previously nuisance pests. However, they now represent a potential threat in the spread of viral diseases. The Aedes aegypti, Aedes albopictus, and Culex species mosquitoes are endemic to the United States and together may transmit a variety of viral diseases of growing concern, including West Nile virus, chikungunya, dengue fever, and Zika virus. The Centers for Disease Control and Prevention and the Environmental Protection Agency (EPA) recommend N,N-diethyl-meta-toluamide (DEET) as a first-line mosquito repellent, but for patients refusing to use DEET or other conventional repellents, guidance is limited to any EPA-registered product. Therefore, we conducted a systematic review of the literature to identify which EPA-registered personal mosquito repellent provides the best protection from A. aegypti, A. albopictus, and Culex spp. mosquitoes. We abstracted data from 62 published reports of EPA-registered mosquito repellents. The conventional repellent picaridin has the strongest data to support its use as a second-line agent, while IR3535 and oil of lemon eucalyptus are reasonably effective natural products. Citronella, catnip, and 2-undecanone offer limited protection or have limited data. These results can be used by pharmacists and other health care professionals to advise patients on the selection of an EPA-registered mosquito repellent. Regardless of the repellent chosen, it is vital for patients to follow all instructions/precautions in the product labeling to ensure safe and effective use. © 2016 Pharmacotherapy Publications, Inc.

Uninvited guests: traditional insect repellents in Estonia used against the clothes moth Tineola bisselliella, human flea Pulex irritons and bedbug Cimex lectularius.

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Sõukand, Renata; Kalle, Raivo; Svanberg, Ingvar

2010-01-01

Extensive folklore records from pre-modern Estonia give us an excellent opportunity to study a variety of local plant knowledge and plant use among the peasantry in various parts of the country. One important biocultural domain where plant knowledge has been crucial was in the various methods of combating different ectoparasites that cohabited and coexisted with humans and their domestic animals. Some of these methods were widely known (world-wide, Eurasia, Europe, Baltic Rim), while others were more local. Here we discuss ways of reducing clothes moths Tineola bisselliella (Hummel) (Lepidoptera: Tineidae), human fleas Pulex irritons L. (Siphonaptera: Pulicidae) and bedbugs Cimex lectularius L. (Hemiptera: Cimicidae) with the help of plants. Various taxa used as traditional repellents have been identified. The use of plants as repellents and their toxic principles are also discussed from a comparative perspective.

Water repellent soils: the case for unsaturated soil mechanics

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Beckett Christopher

2016-01-01

Full Text Available Water repellent (or “hydrophobic” or “non-wetting” soils have been studied by soil scientists for well over a century. These soils are typified by poor water infiltration, which leads to increased soil erosion and poor crop growth. However, the importance of water repellence on determining soil properties is now becoming recognised by geotechnical engineers. Water repellent soils may, for example, offer novel solutions for the design of cover systems overlying municipal or mine waste storage facilities. However, investigations into factors affecting their mechanical properties have only recently been initiated. This purpose of this paper is to introduce geotechnical engineers to the concept of water repellent soils and to discuss how their properties can be evaluated under an unsaturated soils framework. Scenarios in which water repellent properties might be relevant in geotechnical applications are presented and methods to quantify these properties in the laboratory and in the field examined.

Repellent activities of dichloromethane extract of Allium sativum (garlic) (Liliaceae) against Hyalomma rufipes (Acari).

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Nchu, Felix; Magano, Solomon R; Eloff, Jacobus N

2016-12-02

Dichloromethane (DCM) extract of garlic (Allium sativum Linn.) bulbs was assessed for its repellent effect against the hard tick, Hyalomma rufipes (Acari: Ixodidae) using two tick behavioural bioassays; Type A and Type B repellency bioassays, under laboratory conditions. These bioassays exploit the questing behaviour of H. rufipes, a tick that in nature displays ambush strategy, seeking its host by climbing up on vegetation and attaching to a passing host. One hundred microlitres (100 µL) of the test solution containing DCM extract of garlic bulbs and DCM at concentrations of 0.35%, 0.7% or 1.4% w/v were evaluated. DCM only was used for control. Tick repellency increased significantly (R2 = 0.98) with increasing concentration (40.03% - 86.96%) yielding an EC50 of 0.45% w/v in Type B repellency bioassay. At concentration of 1.4% w/v, the DCM extract of garlic bulbs produced high repellency index of 87% (male ticks) and 87.5% (female ticks) in the Type A repellency bioassay. Only 4% avoidance of male ticks or female ticks was recorded in the Type B repellency bioassay. In the corresponding controls, the mean numbers of non-repelled male or female ticks were 80% and 41 males or 38 females of 50 ticks in the Type A and Type B repellency bioassays, respectively. The variations in the results could be attributed to the difference in tick repellent behaviours that were assessed by the two repellency bioassays; the Type A repellency bioassay assessed repellent effect of garlic extracts without discriminating between deterrence and avoidance whereas the Type B repellency bioassay only assessed avoidance response. Generally, DCM extract of garlic was repellent against H. rufipes, albeit weak tick repellency was obtained in the Type B repellency bioassay. Furthermore, this study established that the tick repellent activity of garlic extracts is predominantly by deterrence.

An unusual complication of snake bite

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Mary Grace

2014-01-01

Full Text Available Anterior pituitary hypofunction is a well-known complication following snake bite. However, central diabetes insipidus as a complication of snake bite is only rarely reported in the literature. We are reporting a case of central diabetes insipidus, which developed as sequelae to viper bite.

Spider Bites: First Aid

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... care immediately if: You were bitten by a black widow or brown recluse spider You are unsure whether the bite ... in the South. Signs and symptoms of a black widow spider bite may include: At ... fever and nausea Brown recluse spider The brown recluse spider has a ...

The relationship between oral tori and bite force.

Science.gov (United States)

Jeong, Chan-Woo; Kim, Kyung-Ho; Jang, Hyo-Won; Kim, Hye-Sun; Huh, Jong-Ki

2018-01-12

Objective The relationship between bite force and torus palatinus or mandibularis remains to be explained. The major aim of this study was to determine the correlation between bite force and oral tori. Methods The bite force of 345 patients was measured with a bite force recorder; impressions of the shape and size of the oral tori were taken on plaster models prior to orthodontic treatments. Subsequently, the relationship between oral tori and bite force was analyzed. Results The size, shape, and incidence of torus palatinus was not significantly correlated with bite force. However, the size of torus mandibularis increased significantly in proportion to the bite force (p = 0.020). The occurrence of different types of oral tori was not correlated with the bite force. Discussion The size of torus mandibularis provides information about bite force and can thus be used to clinically assess occlusal stress.

Monkey Bites among US Military Members, Afghanistan, 2011

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Baker, Katheryn A.

2012-01-01

Bites from Macaca mulatta monkeys, native to Afghanistan, can cause serious infections. To determine risk for US military members in Afghanistan, we reviewed records for September–December 2011. Among 126 animal bites and exposures, 10 were monkey bites. Command emphasis is vital for preventing monkey bites; provider training and bite reporting promote postexposure treatment. PMID:23017939

21 CFR 882.5070 - Bite block.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Bite block. 882.5070 Section 882.5070 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Therapeutic Devices § 882.5070 Bite block. (a) Identification. A bite block...

Open bite in prematurely born children.

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Harila, V; Heikkinen, T; Grön, M; Alvesalo, L

2007-01-01

The aims of this study were to: examine the expression of open bite in prematurely born children and discuss the etiological factors that may lead to bite it. The subjects were 328 prematurely born (cross-sectional study of the Collaborative Perinatal Project in the 1960s and 1970s. Dental documents, including casts and photographs, were taken once at the age of 6-12 years in the mixed dentition. The occlusion was recorded by examining and measuring the hard stone casts. Vertical open bite was recorded only for full erupted teeth. The statistical method used was chi-square analysis. Significant differences in the incidence of anterior open bite (from left to right canine) was found between the preterm and control groups and between gender and ethnic groups. The prevalence of anterior open bite was nearly 9% in the preterm group and almost 7% in the control group. African Americans (9%) had a significantly greater incidence of open bite than Caucasians (3%; Pbite than boys (8% vs 6%; Pbite was increased--especially in preterm African American boys compared to controls (11% vs 8%). The results show differences in the development of anterior open bite between ethnic and gender groups. Premature birth may also influence dental occlusal development. Of importance are the patient's: general health condition; respiratory infections; inadequate nasal- and mouth-breathing; oral habits; and other medical problems. Preterm children may be relatively more predisposed to etiological factors for the development of anterior open bite.

A placebo controlled clinical trial investigating the efficacy of a homeopathic after-bite gel in reducing mosquito bite induced erythema.

Science.gov (United States)

Hill, N; Stam, C; Tuinder, S; van Haselen, R A

1995-01-01

A randomised, placebo controlled clinical trial was conducted to examine the efficacy of a homeopathic after-bite gel in the symptomatic relief of mosquito bites. Sixty eight healthy volunteers were bitten under laboratory conditions by Aedes aegypti mosquitoes at three spots, on the ventral aspect of the forearm. One bite was treated with the homeopathic after-bite gel, another bite with a placebo gel which was identical in appearance and smell to the homeopathic after-bite gel, and the third bite remained untreated. Immediately after the bites and 1, 3, 6, 26 and 31 hours post-bite, the length and width of the erythema were measured with a calliper, and photographs were taken of the bite sites from which the size of the erythema was subsequently determined. This was followed by assessment of the extent of itching with a verbal analogue scale, and finally treatment took place. For each spot the total erythema was calculated as the area under the plotted curve of the erythema at different time points (mm2*h) and the total sum of the itch scores was determined. For the bites treated with the homeopathic after-bite gel the median total erythema was 10.500 mm2*h. For the spots treated with the placebo gel and the untreated spots the median total erythema was 12.900 mm2*h and 13.300 mm2*h, respectively. The difference between the spots treated with the homeopathic after-bite gel and the untreated spots came close to significance (two-tailed P = 0.06), which was not the case for the difference between the spots treated with the homeopathic after-bite gel and the spots treated with placebo gel (P = 0.13). After pooling the data of a very similar previous pilot study and the present study (ntotal = 83), the homeopathic after-bite gel was significantly superior to no treatment (two-tailed P = 0.003) as well as to placebo gel (two-tailed P = 0.03). Comparing itching after the three treatments, no significant differences could be demonstrated. The extent of itching was

Water retention of repellent and subcritical repellent soils: New insights from model and experimental investigations

Science.gov (United States)

Czachor, H.; Doerr, S. H.; Lichner, L.

2010-01-01

SummarySoil organic matter can modify the surface properties of the soil mineral phase by changing the surface tension of the mineral surfaces. This modifies the soil's solid-water contact angle, which in turn would be expected to affect its water retention curve (SWRC). Here we model the impact of differences in the soil pore-water contact angle on capillarity in non-cylindrical pores by accounting for their complex pore geometry. Key outcomes from the model include that (i) available methods for measuring the Young's wetting angle on soil samples are insufficient in representing the wetting angle in the soil pore space, (ii) the wetting branch of water retention curves is strongly affected by the soil pore-water contact angle, as manifest in the wetting behavior of water repellent soils, (iii) effects for the drying branch are minimal, indicating that both wettable and water repellent soils should behave similarly, and (vi) water retention is a feature not of only wettable soils, but also soils that are in a water repellent state. These results are tested experimentally by determining drying and wetting branches for (a) 'model soil' (quartz sands with four hydrophobization levels) and (b) five field soil samples with contrasting wettability, which were used with and without the removal of the soil organic matter. The experimental results support the theoretical predictions and indicate that small changes in wetting angle can cause switches between wettable and water repellent soil behavior. This may explain the common observation that relatively small changes in soil water content can cause substantial changes in soil wettability.

β-caryophyllene emitted from a transgenic Arabidopsis or chemical dispenser repels Diaphorina citri, vector of Candidatus Liberibacters.

Science.gov (United States)

Alquézar, Berta; Volpe, Haroldo Xavier Linhares; Magnani, Rodrigo Facchini; de Miranda, Marcelo Pedreira; Santos, Mateus Almeida; Wulff, Nelson Arno; Bento, Jose Mauricio Simões; Parra, José Roberto Postali; Bouwmeester, Harro; Peña, Leandro

2017-07-17

Production of citrus, the main fruit tree crop worldwide, is severely threatened by Huanglongbing (HLB), for which as yet a cure is not available. Spread of this bacterial disease in America and Asia is intimately connected with dispersal and feeding of the insect vector Diaphorina citri, oligophagous on rutaceous host plants. Effective control of this psyllid is an important component in successful HLB management programs. Volatiles released from the non-host guava have been shown to be repellent to the psyllid and to inhibit its response to citrus odour. By analysing VOC emission from guava we identified one volatile compound, (E)-β-caryophyllene, which at certain doses exerts a repellent effect on D. citri. Non-host plant rejection mediated by (E)-β-caryophyllene is demonstrated here by using Arabidopsis over-expression and knock-out lines. For the first time, results indicate that genetically engineered Arabidopsis plants with modified emission of VOCs can alter the behaviour of D. citri. This study shows that transgenic plants with an inherent ability to release (E)-β-caryophyllene can potentially be used in new protection strategies of citrus trees against HLB.

How to Stop Biting Your Nails

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Full Text Available ... of hangnails, or other triggers, such as boredom, stress, or anxiety. By figuring out what causes you to bite your nails, you can figure out how to avoid these situations and develop a plan to stop. Just knowing when you’re inclined to bite may help solve the problem. Try to gradually stop biting ...

Actividad repelente de aceites esenciales contra las picaduras de Lutzomyia migonei (Diptera: Psychodidae

Directory of Open Access Journals (Sweden)

Elsa Nieves

2010-12-01

insect species. The present study evaluated the repellent effect of essential oils extracted from 8 plants species against bites of Lutzomyia migonei, the Leishmania vector. The essential oils were extracted by steam destillation in Clevenger chamber, from the following plants: Hyptis suaveolens, Pimenta racemosa, Piper marginatum, Monticalia imbricatifolia, Pseudognaphalium caeruleocanum, Espeletia shultzii, Plecthranthus amboinicus and Cinnamomun zeylanicum. Repellency tests were performed under laboratory conditions by the human hand method in cage assays, using female colonies of L. migonei. The more effective oils were tested at variable concentrations on different volunteers. The protection percentage and time were calculated. The results showed what oils of P. caeruleocanum and C. zeylanicum were the most effective. Although P. amboinicus oil also had repellent effect showed an irritant effect. The oils P. marginatum, H. suaveolens and P. racemosa showed no repellent effect, while the rest of oil extracts showed significant repellency in variable degrees. P. caeruleocanum and C. zeylanicum oils provided the 95% protection against bites of L. migonei for 3h. The P. caeruleocanum oil showed the greatest protection time, with a mean over 4h and 3h at concentrations of 50% and 10% respectively. The results suggest that the P. caeruleocanum oil could represent a potential natural repellent against Leishmania vectors. Rev. Biol. Trop. 58 (4: 1549-1560. Epub 2010 December 01.

A qualitative investigation of the perceptions of female dog-bite victims and implications for the prevention of dog bites.

Science.gov (United States)

Westgarth, Carri; Watkins, Francine

2015-01-01

Preventing dog bites is an increasingly important public health and political issue with implications for both human and animal health and welfare. Expert opinion is that most bites are preventable. Intervention materials have been designed to educate people on how to assess the body language of dogs, evaluate risk, and take appropriate action. The effectiveness of this approach is rarely evaluated and the incidence of dog bites is thought to be increasing. Is the traditional approach to dog bite prevention working as well as it should? In this novel, small scale qualitative study, the perceptions of victims regarding their dog bite experience were explored in-depth. The study recruited 8 female participants who had been bitten by a dog in the past 5 years. In-depth, one-to-one interviews were conducted, transcribed, and analyzed using thematic analysis. The findings indicate that dog bites may not be as easily preventable as previously presumed, and that education about dog body language may not prevent some types of dog bites. The reasons participants were bitten were multifaceted and complex. In some cases, there was no interaction with the dog before the bite so there was no opportunity to assess the situation and modify behavior around the dog accordingly. Identifying who was to blame, and had responsibility for preventing the bite, was straightforward for the participants in hindsight. Those bitten blamed themselves and/or the dog owner, but not the dog. Most participants already felt they had a theoretical knowledge that would allow them to recognize dog aggression before the dog bite, yet participants, especially those who worked regularly with dogs, routinely believed, "it would not happen to me." We also identified an attitude that bites were "just one of those things," which could also be a barrier prevention initiatives. Rather than being special to the human-canine relationship, the attitudes discovered mirror those found in other areas of injury

Natural and fire-induced soil water repellency in a Portugese Shrubland

NARCIS (Netherlands)

Stoof, C.R.; Moore, D.; Ritsema, C.J.; Dekker, L.W.

2011-01-01

Post-fire land degradation is often attributed to fire-induced soil water repellency, despite the fact that soil water repellency is a natural phenomenon in many soils and is therefore not necessarily caused by fire. To improve our understanding of the role of soil water repellency in causing

Annual incidence of snake bite in rural bangladesh.

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Ridwanur Rahman

Full Text Available BACKGROUND: Snake bite is a neglected public health problem in the world and one of the major causes of mortality and morbidity in many areas, particularly in the rural tropics. It also poses substantial economic burdens on the snake bite victims due to treatment related expenditure and loss of productivity. An accurate estimate of the risk of snake bite is largely unknown for most countries in the developing world, especially South-East Asia. METHODOLOGY/PRINCIPAL FINDINGS: We undertook a national epidemiological survey to determine the annual incidence density of snake bite among the rural Bangladeshi population. Information on frequency of snake bite and individuals' length of stay in selected households over the preceding twelve months was rigorously collected from the respondents through an interviewer administered questionnaire. Point estimates and confidence intervals of the incidence density of snake bite, weighted and adjusted for the multi-stage cluster sampling design, were obtained. Out of 18,857 study participants, over one year a total of 98 snake bites, including one death were reported in rural Bangladesh. The estimated incidence density of snake bite is 623.4/100,000 person years (95% C I 513.4-789.2/100,000 person years. Biting occurs mostly when individuals are at work. The majority of the victims (71% receive snake bites to their lower extremities. Eighty-six percent of the victims received some form of management within two hours of snake bite, although only three percent of the victims went directly to either a medical doctor or a hospital. CONCLUSIONS/SIGNIFICANCE: Incidence density of snake bite in rural Bangladesh is substantially higher than previously estimated. This is likely due to better ascertainment of the incidence through a population based survey. Poor access to health services increases snake bite related morbidity and mortality; therefore, effective public health actions are warranted.

Role of plants and plant based products towards the control of insect pests and vectors: A novel review

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Elumalai Kuppusamy

2016-10-01

Full Text Available Insect pests bear harmful effects causing great loss to the agricultural crops, stored agricultural products and vector mosquitoes can cause diseases to human. Plants possess an array of vast repository of phytochemicals and have been used to cure many diseases and to control the infestation of insect pests from time immemorial. Plants are easily biodegradable and ecologically safe for treating on the stored or on the field crops against pests to prevent from further damage or loss of stored products or preventing human from mosquito bites, thus preventing the spreading of dreadful diseases such as chikungunya and malaria. Hence, this review can give a clear insecticidal, pesticidal and mosquitocidal property of several plants against the insect pests and vectors.

Attracting and repelling in homogeneous signal processes

International Nuclear Information System (INIS)

Downarowicz, T; Grzegorek, P; Lacroix, Y

2010-01-01

Attracting and repelling are discussed on two levels: in abstract signal processes and in signal processes arising as returns to a fixed set in an ergodic dynamical system. In the first approach, among other things, we give three examples in which the sum of two Poisson (hence neutral—neither attracting nor repelling) processes comes out either neutral or attracting, or repelling, depending on how the two processes depend on each other. The main new result of the second type concerns so-called 'composite events' in the form of a union of all cylinders over blocks belonging to the δ-ball in the Hamming distance around a fixed block. We prove that in a typical ergodic nonperiodic process the majority of such 'composite events' reveal strong attracting. We discuss the practical interpretation of this result

Marine animal stings or bites

Science.gov (United States)

Stings - marine animals; Bites - marine animals ... Things you can do to prevent a marine animal sting or bite include: Swim near a lifeguard. Observe posted signs that may warn of danger from jellyfish or other hazardous marine life. ...

Ceramic coatings for water-repellent textiles

Science.gov (United States)

Colleoni, C.; Esposito, F.; Guido, E.; Migani, V.; Trovato, V.; Rosace, G.

2017-10-01

In recent years, ceramic coatings have been widely studied for their potential performance in many scientific and technological fields. Ceramic coatings are also used as a textile-finishing agent to impart several properties such as anti-bacterial, anti-abrasion, flame retardant. In this study, fluoro free water repellent finishings have been developed to assess the features of the silica films on the textile fabrics. The water repellency of the treated samples has been evaluated by different tests such as water contact angle, water uptake and drop test.

Three-dimensional analyses of human bite-force magnitude and moment.

Science.gov (United States)

van Eijden, T M

1991-01-01

The effect of the three-dimensional orientation of occlusal force on maximal bite-force magnitude was examined in seven human subjects at three different unilateral anteroposterior bite positions (canine, second premolar and second molar). At each position, bite-force magnitude was registered in 17 precisely defined directions using a three-component force transducer and a feedback method. In addition, to assess the efficiency of transfer of muscle to bite force, for bites produced in the sagittal plane, moment-arm length was determined and the produced bite-force moment calculated. The results showed that the largest possible bite force was not always produced in a direction perpendicular to the occlusal plane. Generally, maximal bite force in medial and posterior directions was larger than that in, respectively, corresponding lateral and anterior directions. In each direction the produced force was larger at the posterior bite point than at the anterior bite point. The combined moment produced by the jaw muscles was largest for vertical bites, smallest for posteriorly directed bites and intermediate for anteriorly directed bites. In the case of vertically and anteriorly directed bites the produced moment did not vary significantly with the bite position. Hence, for these bite positions the jaw closing moment of the muscles must have kept constant. In the case of posteriorly directed bites the produced moment decreased when bite position changed from the anterior to the posterior side of the dentition. This indicated that jaw muscle activity had declined.

Case Report of a Newborn Injured By Human Bite

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Emel Ataoğlu

2015-03-01

Full Text Available Bite is a type of wound received from the teeth of an animal, including humans. Human bites are third leading cause of all bites after dog and cat bites. Human bites are severe wounds due to the risk of contamination with mix oral flora and rapid tissue destruction. Bite wounds created by humans are seen in variety of circumstances including aggression, rape, murder, and child abuse. Oral cavity contains beta-hemolytic streptococci, anaerobes and other microorganisms. There have been reported cases of septicemia, severe necrotizing fasciitis, HIV infection, and death caused by human bites. Early reporting and treatment of bite wounds decrease the number and severity of wound infection. Here, we present the case of human bite in a nine-day-old girl and discuss the treatment approaches in the light of the relevant literature.

Effects of bruxism on the maximum bite force

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Todić Jelena T.

2017-01-01

Full Text Available Background/Aim. Bruxism is a parafunctional activity of the masticatory system, which is characterized by clenching or grinding of teeth. The purpose of this study was to determine whether the presence of bruxism has impact on maximum bite force, with particular reference to the potential impact of gender on bite force values. Methods. This study included two groups of subjects: without and with bruxism. The presence of bruxism in the subjects was registered using a specific clinical questionnaire on bruxism and physical examination. The subjects from both groups were submitted to the procedure of measuring the maximum bite pressure and occlusal contact area using a single-sheet pressure-sensitive films (Fuji Prescale MS and HS Film. Maximal bite force was obtained by multiplying maximal bite pressure and occlusal contact area values. Results. The average values of maximal bite force were significantly higher in the subjects with bruxism compared to those without bruxism (p 0.01. Maximal bite force was significantly higher in the males compared to the females in all segments of the research. Conclusion. The presence of bruxism influences the increase in the maximum bite force as shown in this study. Gender is a significant determinant of bite force. Registration of maximum bite force can be used in diagnosing and analysing pathophysiological events during bruxism.

Effectiveness of Gel Repellents on Feral Pigeons

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Birte Stock

2013-12-01

Full Text Available Millions of feral pigeons (Columba livia live in close association with the human population in our cities. They pose serious health risks to humans and lead to high economic loss due to damage caused to buildings. Consequently, house owners and city authorities are not willing to allow pigeons on their buildings. While various avian repellents are regularly introduced onto the market, scientific proof of efficacy is lacking. This study aimed at testing the effectiveness of two avian gel repellents and additionally examined their application from animal welfare standpoint. The gels used an alleged tactile or visual aversion of the birds, reinforced by additional sensory cues. We mounted experimental shelves with the installed repellents in a pigeon loft and observed the behavior of free-living feral pigeons towards the systems. Both gels showed a restricted, transient repellent effect, but failed to prove the claimed complete effectiveness. Additionally, the gels’ adhesive effect remains doubtful in view of animal welfare because gluing of plumage presents a risk to feral pigeons and also to other non-target birds. This study infers that both gels lack the promised complete efficacy, conflict with animal welfare concerns and are therefore not suitable for feral pigeon management in urban areas.

Repellency of Plant Extracts against the Legume Flower Thrips Megalurothrips sjostedti (Thysanoptera: Thripidae

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Andnet Abtew

2015-06-01

Full Text Available Megalurothrips sjostedti Trybom is an important pest of cowpea (Vigna unguiculata L. in Africa. To propose an alternative to chemical control, the repellency of 24 plant extracts was evaluated against adult female thrips of M. sjostedti in the laboratory. Plant extracts in ethanol were separately applied on a filter paper disk in a still air visual cue olfactometer. The results showed highly significant differences in repellency among extract type, concentration and their interactions. We classified the level of repellency into four categories as strong, good, moderate and weak or non- repellent based on hierarchical ascendant classification. We identified Piper nigrum, Cinnamomum zeylanicum, Cinnamomum cassia as strong repellents. Five extracts were classified as good, eight as moderate and the remaining eight extracts were weak or non-repellent. Repellency of the extracts increased with the concentration suggesting that the behavioral response of M. sjostedti was dose-dependent. Mono- and sesquiterpene hydrocarbon compounds from seven highly repellent extracts were identified by gas chromatography-mass spectrometry (GC/MS. The use of repellent extracts could be useful in developing integrated pest management strategies for thrips on legume crops. In this regard, the specific modes of action of the identified compounds need to be investigated to incorporate them into the existing crop protection strategies.

[Bites of venomous snakes in Switzerland].

Science.gov (United States)

Plate, Andreas; Kupferschmidt, Hugo; Schneemann, Markus

2016-06-08

Although snake bites are rare in Europe, there are a constant number of snake bites in Switzerland. There are two domestic venomous snakes in Switzerland: the aspic viper (Vipera aspis) and the common European adder (Vipera berus). Bites from venomous snakes are caused either by one of the two domestic venomous snakes or by an exotic venomous snake kept in a terrarium. Snake- bites can cause both a local and/or a systemic envenoming. Potentially fatal systemic complications are related to disturbances of the hemostatic- and cardiovascular system as well as the central or peripheral nervous system. Beside a symptomatic therapy the administration of antivenom is the only causal therapy to neutralize the venomous toxins.

Substitution of PFAS chemistry in outdoor apparel and the impact on repellency performance.

Science.gov (United States)

Hill, Philippa J; Taylor, Mark; Goswami, Parikshit; Blackburn, Richard S

2017-08-01

Intensifying legislation and increased research on the toxicological and persistent nature of per- and polyfluoroalkyl substances (PFASs) have recently influenced the direction of liquid repellent chemistry use; environmental, social, and sustainability responsibilities are at the crux. Without PFAS chemistry, it is challenging to meet current textile industry liquid repellency requirements, which is a highly desirable property, particularly in outdoor apparel where the technology helps to provide the wearer with essential protection from adverse environmental conditions. Herein, complexities between required functionality, legislation and sustainability within outdoor apparel are discussed, and fundamental technical performance of commercially available long-chain (C8) PFASs, shorter-chain (C6) PFASs, and non-fluorinated repellent chemistries finishes are evaluated comparatively. Non-fluorinated finishes provided no oil repellency, and were clearly inferior in this property to PFAS-finished fabrics that demonstrated good oil-resistance. However, water repellency ratings were similar across the range of all finished fabrics tested, all demonstrating a high level of resistance to wetting, and several non-fluorinated repellent fabrics provide similar water repellency to long-chain (C8) PFAS or shorter-chain (C6) PFAS finished fabrics. The primary repellency function required in outdoor apparel is water repellency, and we would propose that the use of PFAS chemistry for such garments is over-engineering, providing oil repellency that is in excess of user requirements. Accordingly, significant environmental and toxicological benefits could be achieved by switching outdoor apparel to non-fluorinated finishes without a significant reduction in garment water-repellency performance. These conclusions are being supported by further research into the effect of laundering, abrasion and ageing of these fabrics. Copyright © 2017 Elsevier Ltd. All rights reserved.

Preferential flow in water-repellent sandy soils : model development and lysimeter experiments

NARCIS (Netherlands)

Rooij, de G.H.

1996-01-01

When water enters a water-repellent topsoil, preferential flow paths develop and the flow bypasses a large part of the unsaturated zone. Therefore, preferential flow caused by water- repellency is expected to accelerate solute leaching to the groundwater. In soils with water-repellent

Essential oils and their compositions as spatial repellents for pestiferous social wasps.

Science.gov (United States)

Zhang, Qing-He; Schneidmiller, Rodney G; Hoover, Doreen R

2013-04-01

The study objectives were: (1) to field test potential repellency of common essential oils against several pestiferous social wasps (Hymenoptera: Vespidae), using attractant-baited traps; (2) to identify vespid antennally active compounds from the repellent essential oils; (3) to determine potential repellency of these electroantennographic detection (EAD) active compounds in the field. Of the 21 essential oils tested, 17 showed significant repellency on yellowjackets [mainly Vespula pensylvanica (Saussure)] and paper wasps [mainly Polistes dominulus (Christ)]: clove, pennyroyal, lemongrass, ylang ylang, spearmint, wintergreen, sage, rosemary, lavender, geranium, patchouli, citronella, Roman chamomile, thyme, fennel seed, anise and peppermint. Two essential oil mixtures - 3EO-mix (clove, geranium and lemongrass) and 4EO-mix (clove, geranium, lemongrass and rosemary) - totally blocked the attraction of vespid workers. Twenty-nine vespid antennally active compounds were identified from solid-phase microextraction (SPME) samples of 11 strongly repellent essential oils by GC-EAD/MS techniques. Among the synthetic EAD-active compounds field tested, eugenol, P/I-menthone, pulegone, α/β-thujone, l-carvone, E/Z-citral, citronellal, methyl benzoate, benzyl acetate, methyl salicylate and 3-octanol showed a significant repellency on vespid workers. These compounds are likely responsible for the repellency of their corresponding essential oils. These repellent essential oils and their active compositions have great potential for efficient, environmentally sound semiochemical-based IPM of pestiferous vespid wasps. © 2012 Society of Chemical Industry.

Esthetic correction in open bite

Directory of Open Access Journals (Sweden)

Swapnil Parlani

2011-01-01

Full Text Available Deleterious oral habits, which are persistent, can lead to poor esthetics of a beautiful face. Conventional treatment modalities for an open bite usually include orthodontic treatment and/or skeletal surgery. This article focuses on a different treatment modality for an anterior open bite.

Bug bites and stings: When to see a dermatologist

Medline Plus

Full Text Available ... Tips to prevent and treat bug bites Although most bug bites are harmless, some can spread dangerous ... one’s greatest efforts, bug bites still happen. Fortunately, most bug bites and stings can be safely treated ...

A persistent homology approach to collective behavior in insect swarms

Science.gov (United States)

Sinhuber, Michael; Ouellette, Nicholas T.

Various animals from birds and fish to insects tend to form aggregates, displaying self-organized collective swarming behavior. Due to their frequent occurrence in nature and their implications for engineered, collective systems, these systems have been investigated and modeled thoroughly for decades. Common approaches range from modeling them with coupled differential equations on the individual level up to continuum approaches. We present an alternative, topology-based approach for describing swarming behavior at the macroscale rather than the microscale. We study laboratory swarms of Chironomus riparius, a flying, non-biting midge. To obtain the time-resolved three-dimensional trajectories of individual insects, we use a multi-camera stereoimaging and particle-tracking setup. To investigate the swarming behavior in a topological sense, we employ a persistent homology approach to identify persisting structures and features in the insect swarm that elude a direct, ensemble-averaging approach. We are able to identify features of sub-clusters in the swarm that show behavior distinct from that of the remaining swarm members. The coexistence of sub-swarms with different features resembles some non-biological systems such as active colloids or even thermodynamic systems.

Mosquito repellent activity of essential oils of aromatic plants growing in Argentina.

Science.gov (United States)

Gillij, Y G; Gleiser, R M; Zygadlo, J A

2008-05-01

Mosquitoes are important vectors of diseases and nuisance pests. Repellents minimize contact with mosquitoes. Repellents based on essential oils (EO) are being developed as an alternative to DEET (N,N-diethyl-m-methylbenzamide), an effective compound that has disadvantages including toxic reactions, and damage to plastic and synthetic fabric. This work evaluated the repellency against Aedes aegypti of EO from aromatic plants that grow in Argentina: Acantholippia seriphioides, Achyrocline satureioides, Aloysia citriodora, Anemia tomentosa, Baccharis spartioides, Chenopodium ambrosioides, Eucalyptus saligna, Hyptis mutabilis, Minthostachys mollis, Rosmarinus officinalis, Tagetes minuta and Tagetes pusilla. Most EO were effective. Variations depending on geographic origin of the plant were detected. At a 90% EO concentration, A. satureoides and T. pusilla were the least repellent. At concentrations of 12.5% B. spartioides, R. officinalis and A. citriodora showed the longest repellency times. Comparisons of the principal components of each EO suggest that limonene and camphor were the main components responsible for the repellent effects.

Bite Forces and Their Measurement in Dogs and Cats

Directory of Open Access Journals (Sweden)

Se Eun Kim

2018-04-01

Full Text Available Bite force is generated by the interaction of the masticatory muscles, the mandibles and maxillae, the temporomandibular joints (TMJs, and the teeth. Several methods to measure bite forces in dogs and cats have been described. Direct in vivo measurement of a bite in dogs has been done; however, bite forces were highly variable due to animal volition, situation, or specific measurement technique. Bite force has been measured in vivo from anesthetized dogs by electrical stimulation of jaw adductor muscles, but this may not be reflective of volitional bite force during natural activity. In vitro bite forces have been estimated by calculation of the force produced using mechanical equations representing the jaw adductor muscles and of the mandible and skull structure Bite force can be estimated in silico using finite element analysis (FEA of the computed model of the anatomical structures. FEA can estimate bite force in extinct species; however, estimates may be lower than the measurements in live animals and would have to be validated specifically in domestic dogs and cats to be reliable. The main factors affecting the bite forces in dogs and cats are body weight and the skull’s morphology and size. Other factors such as oral pain, TMJ disorders, masticatory muscle atrophy, and malocclusion may also affect bite force. Knowledge of bite forces in dogs and cats is essential for various clinical and research fields such as the development of implants, materials, and surgical techniques as well as for forensic medicine. This paper is a summary of current knowledge of bite forces in dogs and cats, including the effect of measurement methods and of other factors.

Bite Forces and Their Measurement in Dogs and Cats.

Science.gov (United States)

Kim, Se Eun; Arzi, Boaz; Garcia, Tanya C; Verstraete, Frank J M

2018-01-01

Bite force is generated by the interaction of the masticatory muscles, the mandibles and maxillae, the temporomandibular joints (TMJs), and the teeth. Several methods to measure bite forces in dogs and cats have been described. Direct in vivo measurement of a bite in dogs has been done; however, bite forces were highly variable due to animal volition, situation, or specific measurement technique. Bite force has been measured in vivo from anesthetized dogs by electrical stimulation of jaw adductor muscles, but this may not be reflective of volitional bite force during natural activity. In vitro bite forces have been estimated by calculation of the force produced using mechanical equations representing the jaw adductor muscles and of the mandible and skull structure Bite force can be estimated in silico using finite element analysis (FEA) of the computed model of the anatomical structures. FEA can estimate bite force in extinct species; however, estimates may be lower than the measurements in live animals and would have to be validated specifically in domestic dogs and cats to be reliable. The main factors affecting the bite forces in dogs and cats are body weight and the skull's morphology and size. Other factors such as oral pain, TMJ disorders, masticatory muscle atrophy, and malocclusion may also affect bite force. Knowledge of bite forces in dogs and cats is essential for various clinical and research fields such as the development of implants, materials, and surgical techniques as well as for forensic medicine. This paper is a summary of current knowledge of bite forces in dogs and cats, including the effect of measurement methods and of other factors.

Biting back: BiTE antibodies as a promising therapy for acute myeloid leukemia.

Science.gov (United States)

Walter, Roland B

2014-06-01

The experience with gemtuzumab ozogamicin has highlighted both the potential value and limitations of antibodies in acute myeloid leukemia (AML). Recently, bispecific T-cell engager (BiTE) antibodies have emerged as a means to harness polyclonal cytotoxic T-cells and cause highly efficient lysis of targeted tumor cells. Promising early results have been obtained with the CD19-directed BiTE antibody, blinatumomab, in patients with acute lymphoblastic leukemia. A first candidate for AML is the CD33/CD3 molecule, AMG 330, for which several recent preclinical studies demonstrated high potency and efficacy in destroying CD33(+) human AML cells. Many questions remain to be addressed, but BiTE antibodies may offer an exciting new tool in a disease for which the outcomes in many patients remain unsatisfactory.

Bioactivities of Ketones Terpenes: Antifungal Effect on F. verticillioides and Repellents to Control Insect Fungal Vector, S. zeamais

OpenAIRE

Pizzolitto, Romina P.; Herrera, Jimena M.; Zaio, Yesica P.; Dambolena, Jose S.; Zunino, Maria P.; Gallucci, Mauro N.; Zygadlo, Julio A.

2015-01-01

Maize is one the most important staple foods in the world. However, numerous pests, such as fungal pathogens, e.g., Fusarium verticillioides, and insects, such as Sitophlilus zeamais, attack maize grains during storage. Many F. verticillioides strains produce fumonisins, one of the most important mycotoxin that causes toxic effects on human and animal health. This situation is aggravated by the insect fungal vector, Sitophlilus zeamais, which contributes to the dispersal of fungal spores, and...

Structure-activity of valencenoid derivatives and their repellence to the Formosan subterranean termite.

Science.gov (United States)

Zhu, Betty C R; Henderson, Gregg; Sauer, Anne M; Yu, Ying; Crowe, William; Laine, Roger A

2003-12-01

Eight valencenoid derivatives were evaluated for their repelling activity against Formosan subterranean termites, Coptotermes formosanus Shiraki. Among them, 1,10-dihydronootkatone was the strongest repellent, and valencene was the weakest. Results of the structure-repellency relationships indicated (1) reduction of the ketone group to the alcohol on position 2 of nootkatone curtailed the activity; (2) because of the low activity of valencene relative to nootkatone that the ketone group was essential for repellent activity; (3) reduction of the 1,10 double bond (1,10-dihydronootkatone and tetrahydronootkatone) produced compounds more repellent than nootkatone; (4) the isopropenyl group probably does not participate in binding as evidenced by no significant difference in the repellent activity among nootkatone (double bond between position 11 and 12), isonootkatone (double bond between position 7 and 11), and 11,12-dihydronootkatone.

The influence of bubbles on the perception carbonation bite.

Directory of Open Access Journals (Sweden)

Paul M Wise

Full Text Available Although many people naively assume that the bite of carbonation is due to tactile stimulation of the oral cavity by bubbles, it has become increasingly clear that carbonation bite comes mainly from formation of carbonic acid in the oral mucosa. In Experiment 1, we asked whether bubbles were in fact required to perceive carbonation bite. Subjects rated oral pungency from several concentrations of carbonated water both at normal atmospheric pressure (at which bubbles could form and at 2.0 atmospheres pressure (at which bubbles did not form. Ratings of carbonation bite under the two pressure conditions were essentially identical, indicating that bubbles are not required for pungency. In Experiment 2, we created controlled streams of air bubbles around the tongue in mildly pungent CO2 solutions to determine how tactile stimulation from bubbles affects carbonation bite. Since innocuous sensations like light touch and cooling often suppress pain, we predicted that bubbles might reduce rated bite. Contrary to prediction, air bubbles flowing around the tongue significantly enhanced rated bite, without inducing perceived bite in blank (un-carbonated solutions. Accordingly, though bubbles are clearly not required for carbonation bite, they may well modulate perceived bite. More generally, the results show that innocuous tactile stimulation can enhance chemogenic pain. Possible physiological mechanisms are discussed.

Bacteremia with Bacteroides pyogenes after a cat bite

DEFF Research Database (Denmark)

Madsen, Ida Ringsborg; Justesen, Ulrik Stenz

2011-01-01

Animal bite wounds are often infected with bacteria from the animal's oral flora. We report what we believe to be the first case of bacteremia with Bacteroides pyogenes resulting from an infected cat bite.......Animal bite wounds are often infected with bacteria from the animal's oral flora. We report what we believe to be the first case of bacteremia with Bacteroides pyogenes resulting from an infected cat bite....

An elaborated feeding cycle model for reductions in vectorial capacity of night-biting mosquitoes by insecticide-treated nets.

Science.gov (United States)

Le Menach, Arnaud; Takala, Shannon; McKenzie, F Ellis; Perisse, Andre; Harris, Anthony; Flahault, Antoine; Smith, David L

2007-01-25

Insecticide Treated Nets (ITNs) are an important tool for malaria control. ITNs are effective because they work on several parts of the mosquito feeding cycle, including both adult killing and repelling effects. Using an elaborated description of the classic feeding cycle model, simple formulas have been derived to describe how ITNs change mosquito behaviour and the intensity of malaria transmission, as summarized by vectorial capacity and EIR. The predicted changes are illustrated as a function of the frequency of ITN use for four different vector populations using parameter estimates from the literature. The model demonstrates that ITNs simultaneously reduce mosquitoes' lifespans, lengthen the feeding cycle, and by discouraging human biting divert more bites onto non-human hosts. ITNs can substantially reduce vectorial capacity through small changes to all of these quantities. The total reductions in vectorial capacity differ, moreover, depending on baseline behavior in the absence of ITNs. Reductions in lifespan and vectorial capacity are strongest for vector species with high baseline survival. Anthropophilic and zoophilic species are affected differently by ITNs; the feeding cycle is lengthened more for anthrophilic species, and the proportion of bites that are diverted onto non-human hosts is higher for zoophilic species. This model suggests that the efficacy of ITNs should be measured as a total reduction in transmission intensity, and that the quantitative effects will differ by species and by transmission intensity. At very high rates of ITN use, ITNs can generate large reductions in transmission intensity that could provide very large reductions in transmission intensity, and effective malaria control in some areas, especially when used in combination with other control measures. At high EIR, ITNs will probably not substantially reduce the parasite rate, but when transmission intensity is low, reductions in vectorial capacity combine with reductions in

How to Stop Biting Your Nails

Medline Plus

Full Text Available ... Mohs AUC MyDermPath+ Psoriasis Patient education resources ... Try to gradually stop biting your nails: Some doctors recommend taking a gradual approach to break the habit. Try to stop biting ...

Evaluation of commercial products for personal protection against mosquitoes.

Science.gov (United States)

Revay, Edita E; Junnila, Amy; Xue, Rui-De; Kline, Daniel L; Bernier, Ulrich R; Kravchenko, Vasiliy D; Qualls, Whitney A; Ghattas, Nina; Müller, Günter C

2013-02-01

Human landing catch studies were conducted in a semi-field setting to determine the efficacy of seven commercial products used for personal protection against mosquitoes. Experiments were conducted in two empty, insecticide free, mesh-enclosed greenhouses, in Israel, with either 1500 Aedes albopictus or 1500 Culex pipiens released on consecutive study nights. The products tested in this study were the OFF!(®) Clip-On™ Mosquito Repellent (Metofluthrin 31.2%) and the Terminix(®) ALLCLEAR(®) Sidekick Mosquito Repeller (Cinnamon oil 10.5%; Eugenol 13%; Geranium oil 21%; Peppermint 5.3%; Lemongrass oil 2.6%), which are personal diffusers; Super Band™ Wristband (22% Citronella oil) and the PIC(®) Citronella Plus Wristband (Geraniol 15%; Lemongrass oil 5%, Citronella oil 1%); the Sonic Insect Repeller Keychain; the Mosquito Guard Patch (Oil of Lemon Eucalyptus 80mg), an adhesive-backed sticker for use on textiles; and the Mosquito Patch (vitamin B1 300mg), a transdermal patch. It was determined that the sticker, transdermal patch, wristbands and sonic device did not provide significant protection to volunteers compared with the mosquito attack rate on control volunteers who were not wearing a repellent device. The personal diffusers: - OFF!(®) Clip-On™ and Terminix(®) ALLCLEAR(®) Sidekick - provided superior protection compared with all other devices in this study. These diffusers reduced biting on the arms of volunteers by 96.28% and 95.26% respectively, for Ae. albopictus, and by 94.94% and 92.15% respectively, for Cx. pipiens. In a second trial conducted to compare these devices directly, biting was reduced by the OFF!(®) Clip-On™ and the Terminix(®) ALLCLEAR(®) by 87.55% and 92.83%, respectively, for Ae. albopictus, and by 97.22% and 94.14%, respectively, for Cx. pipiens. There was no significant difference between the performances of the two diffusers for each species. Copyright © 2012 Elsevier B.V. All rights reserved.

Effects of the spatial repellent metofluthrin on landing rates of outdoor biting anophelines in Cambodia, Southeast Asia.

Science.gov (United States)

Charlwood, J D; Nenhep, S; Protopopoff, N; Sovannaroth, S; Morgan, J C; Hemingway, J

2016-06-01

The emergence of artemisinin-resistant malaria in Southeast Asia is a major problem. The fact that many people become infected with malaria when they are outside has prompted the development of 'spatial' rather than topical repellents. The respective effects of one or four slow-release emanators of metofluthrin, a pyrethroid, were tested in Pailin, Pursat and Koh Kong, Cambodia. Numbers of mosquitoes counted in outdoor landing catches when one or four emanators were suspended close to the collector were compared with control collections. In Pailin, the effects of emanators on catches in Furvela tent traps and Centers for Disease Control (CDC) light traps suspended underneath houses were also investigated. Rate ratios were used to determine differences. A total of 29 255 mosquitoes were collected over 2934 h of landing collections, 87 nights of tent trapping and 81 nights of light trap capture. In Pailin, landing rates were reduced by 48% by a single emanator and by 67% by four emanators (P metofluthrin collections (P > 0.05). These findings suggest that although the product can produce a significant effect, it requires further improvement. © 2016 The Royal Entomological Society.

Preliminary Study of Water Repellent Properties of Red Pepper Seed Oil

Science.gov (United States)

Kurniawan, F.; Madurani, K. A.; Wahyulis, N. C.

2017-03-01

The water-repellent properties of red pepper seed oil (capsicol) have been studied. The oil was coated on the glass surface by spray technique. Water repellent properties were performed by measuring the contact angle of water droplets. The measurement was conducted by varying the drying time of the oil coating at room temperature. The optimum contact angle of the droplets on the glass with capsicol coating is 46.77°, which can be achieved in 30 min of drying time. It also obtained the smallest diameter of the droplets (0.47 cm). The longer drying time decrease the contact angles and increases the diameter. The results were compared with the bare glass and commercial water repellent. The contact angle of the droplets on the glass surface with capsicol coating is higher than bare glass, but lower than glass with commercial water repellent coating. It means that capsicol has the water-repellent properties.

Measurement of dynamic bite force during mastication.

Science.gov (United States)

Shimada, A; Yamabe, Y; Torisu, T; Baad-Hansen, L; Murata, H; Svensson, P

2012-05-01

Efficient mastication of different types and size of food depends on fast integration of sensory information from mechanoreceptors and central control mechanisms of jaw movements and applied bite force. The neural basis underlying mastication has been studied for decades but little progress in understanding the dynamics of bite force has been made mainly due to technical limitations of bite force recorders. The aims of this study were to develop a new intraoral bite force recorder which would allow the study of natural mastication without an increase in the occlusal vertical dimension and subsequently to analyze the relation between electromyographic (EMG) activity of jaw-closing muscles, jaw movements and bite force during mastication of five different types of food. Customized force recorders based on strain gauge sensors were fitted to the upper and lower molar teeth on the preferred chewing side in fourteen healthy and dentate subjects (21-39 years), and recordings were carried out during voluntary mastication of five different kinds of food. Intraoral force recordings were successively obtained from all subjects. anova showed that impulse of bite force as well as integrated EMG was significantly influenced by food (Pmastication with direct implications for oral rehabilitation. We also propose that the control of bite force during mastication is achieved by anticipatory adjustment and encoding of bolus characteristics. © 2012 Blackwell Publishing Ltd.

Bite force measurement based on fiber Bragg grating sensor

Science.gov (United States)

Padma, Srivani; Umesh, Sharath; Asokan, Sundarrajan; Srinivas, Talabattula

2017-10-01

The maximum level of voluntary bite force, which results from the combined action of muscle of mastication, joints, and teeth, i.e., craniomandibular structure, is considered as one of the major indicators for the functional state of the masticatory system. Measurement of voluntary bite force provides useful data for the jaw muscle function and activity along with assessment of prosthetics. This study proposes an in vivo methodology for the dynamic measurement of bite force employing a fiber Bragg grating (FBG) sensor known as bite force measurement device (BFMD). The BFMD developed is a noninvasive intraoral device, which transduces the bite force exerted at the occlusal surface into strain variations on a metal plate. These strain variations are acquired by the FBG sensor bonded over it. The BFMD developed facilitates adjustment of the distance between the biting platform, which is essential to capture the maximum voluntary bite force at three different positions of teeth, namely incisor, premolar, and molar sites. The clinically relevant bite forces are measured at incisor, molar, and premolar position and have been compared against each other. Furthermore, the bite forces measured with all subjects are segregated according to gender and also compared against each other.

Cheek-biting disorder: another stereotypic movement disorder?

Science.gov (United States)

Sarkhel, Sujit; Praharaj, Samir Kumar; Akhtar, Sayeed

2011-12-01

Recurrent cheek biting, a form of self-injurious behavior is a rare entity which presents mostly to dentists and dermatologists. We report a case of recurrent severe cheek biting in an adult male leading to mucosal ulceration. The stereotypic pattern of cheek biting and associated behavior bears striking resemblance to other impulse control disorders. Copyright © 2011 Elsevier Ltd. All rights reserved.

Venomous Snake Bite Injuries at Kitui District Hospital | Kihiko ...

African Journals Online (AJOL)

Background Snake bites are a neglected public health issue in poor rural communities, and the true burden of snake bites is not known. Kitui County has a high incidence of snake bites and no functional snake bite control programs exists. Diagnostic tests for snake species identification are not available and management ...

Microbiology of Animal Bite Wound Infections

Science.gov (United States)

Abrahamian, Fredrick M.; Goldstein, Ellie J. C.

2011-01-01

Summary: The microbiology of animal bite wound infections in humans is often polymicrobial, with a broad mixture of aerobic and anaerobic microorganisms. Bacteria recovered from infected bite wounds are most often reflective of the oral flora of the biting animal, which can also be influenced by the microbiome of their ingested prey and other foods. Bacteria may also originate from the victim's own skin or the physical environment at the time of injury. Our review has focused on bite wound infections in humans from dogs, cats, and a variety of other animals such as monkeys, bears, pigs, ferrets, horses, sheep, Tasmanian devils, snakes, Komodo dragons, monitor lizards, iguanas, alligators/crocodiles, rats, guinea pigs, hamsters, prairie dogs, swans, and sharks. The medical literature in this area has been made up mostly of small case series or case reports. Very few studies have been systematic and are often limited to dog or cat bite injuries. Limitations of studies include a lack of established or inconsistent criteria for an infected wound and a failure to utilize optimal techniques in pathogen isolation, especially for anaerobic organisms. There is also a lack of an understanding of the pathogenic significance of all cultured organisms. Gathering information and conducting research in a more systematic and methodical fashion through an organized research network, including zoos, veterinary practices, and rural clinics and hospitals, are needed to better define the microbiology of animal bite wound infections in humans. PMID:21482724

First molar cross-bite is more closely associated with a reverse chewing cycle than anterior or pre-molar cross-bite during mastication.

Science.gov (United States)

Tomonari, H; Ikemori, T; Kubota, T; Uehara, S; Miyawaki, S

2014-12-01

A posterior cross-bite is defined as an abnormal bucco-lingual relationship between opposing molars, pre-molars or both in centric occlusion. Although it has been reported that patients with unilateral posterior cross-bite often show unique chewing patterns, the relationship between the form of cross-bite and masticatory jaw movement remains unclear in adult patients. The objective of this study was to investigate masticatory jaw movement among different forms of cross-bite. One hundred and one adults were recruited in this study: 27 had unilateral first molar cross-bite (MC group); 28, unilateral pre-molar cross-bite (PC group); 23, anterior cross-bite (AC group); and 23, normal occlusion (control group). Masticatory jaw movement of the lower incisor point was recorded with six degrees of freedom jaw-tracking system during unilateral mastication. Our results showed that the reverse chewing ratio during deliberate unilateral mastication was significantly larger in the MC group than in the PA (P chewing cycle. © 2014 John Wiley & Sons Ltd.

How to Stop Biting Your Nails

Medline Plus

Full Text Available ... biting your nails Nail biting typically begins in childhood and can continue through adulthood, and the side ... set of nails, such as your thumb nails, first. When that’s successful, eliminate your pinky nails, pointer ...

Management of Poisonous Snake Bites in Southern Taiwan

Directory of Open Access Journals (Sweden)

Kao-Ping Chang

2007-10-01

Full Text Available Snake bite envenomation is not uncommon in Taiwan. This study focuses on the pattern of poisonous snake bites and their management in southern Taiwan over a 5-year period. The case histories of 37 patients with poisonous snake bites admitted to the Kaohsiung Medical University Hospital between June 2001 and July 2005 were analyzed retrospectively. Three patients, bitten by unknown species of venomous snakes, were excluded from this study. The frequency of snake bites from each species of snake, the local and systemic manifestations of snake bite, treatment of complications and final outcomes were analyzed. Of the remaining 34 patients, 11 (32.4% were bitten by bamboo vipers, 10 (29.4% by Russell's pit vipers, 8 (23.5% by Taiwan cobras and 5 (14.7% by Taiwan Habu. The majority of snake bites (28 occurred between May and November. Those affected were mainly outdoor hikers (14 and workers (9. The antivenin requirements for treatment in the emergency room were in accordance with standard procedures. No mortality was noted among those envenomed by poisonous snakes. Although poisonous snake bite is not a common life-threatening emergency in the study area, we observed both an environmental risk and a seasonal incidence of snake bite. Keeping the varied clinical manifestations of snake bite in mind is important for effective management. Ready availability and appropriate use of antivenin, close monitoring of patients, institution of ventilatory support and early referral to a larger hospital when required, all help reduce mortality.

Animal Bites

Science.gov (United States)

Wild animals usually avoid people. They might attack, however, if they feel threatened, are sick, or are protecting their ... or territory. Attacks by pets are more common. Animal bites rarely are life-threatening, but if they ...

Soil water repellency in north-eastern Greece with adverse effects of drying on the persistence

NARCIS (Netherlands)

Ziogas, A.K.; Dekker, L.W.; Oostindie, K.; Ritsema, C.J.

2005-01-01

Many soils may be water repellent to some degree, challenging the common perception that soil water repellency is only an interesting aberration. When dry, water repellent soils resist or retard water infiltration into the soil matrix. Soil water repellency often leads to the development of unstable

How to Stop Biting Your Nails

Medline Plus

Full Text Available ... nails, or even an entire hand. The goal is to get to the point where you no longer bite any of your nails. For some people, nail biting may be a sign of a more serious psychological ...

Bite marks on skin and clay: A comparative analysis

Directory of Open Access Journals (Sweden)

R.K. Gorea

2014-12-01

Full Text Available Bite marks are always unique because teeth are distinctive. Bite marks are often observed at the crime scene in sexual and in physical assault cases on the skin of the victims and sometimes on edible leftovers in burglary cases. This piece of evidence is often ignored, but if properly harvested and investigated, bite marks may prove useful in apprehending and successfully prosecuting the criminals. Due to the importance of bite marks, we conducted a progressive randomised experimental study conducted on volunteers. A total of 188 bite marks on clay were studied. Based on these findings, 93.34% of the volunteers could be identified from the bite marks on the clay. In addition, 201 impressions on skin were studied, and out of these cases, 41.01% of the same volunteers could be identified based on the bite mark impressions on the skin.

Engineering Characteristics of Chemically Treated Water-Repellent Kaolin

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Youngmin Choi

2016-12-01

Full Text Available Water-repellent soils have a potential as alternative construction materials that will improve conventional geotechnical structures. In this study, the potential of chemically treated water-repellent kaolin clay as a landfill cover material is explored by examining its characteristics including hydraulic and mechanical properties. In order to provide water repellency to the kaolin clay, the surface of clay particle is modified with organosilanes in concentrations (CO ranging from 0.5% to 10% by weight. As the CO increases, the specific gravity of treated clay tends to decrease, whereas the total organic carbon content of the treated clay tends to increase. The soil-water contact angle increases with an increase in CO until CO = 2.5%, and then maintains an almost constant value (≈134.0°. Resistance to water infiltration is improved by organosilane treatment under low hydrostatic pressure. However, water infiltration resistance under high hydrostatic pressure is reduced or exacerbated to the level of untreated clay. The maximum compacted dry weight density decreases with increasing CO. As the CO increases, the small strain shear modulus increases, whereas the effect of organosilane treatment on the constrained modulus is minimal. The results indicate that water-repellent kaolin clay possesses excellent engineering characteristics for a landfill cover material.

Engineering Characteristics of Chemically Treated Water-Repellent Kaolin

Science.gov (United States)

Choi, Youngmin; Choo, Hyunwook; Yun, Tae Sup; Lee, Changho; Lee, Woojin

2016-01-01

Water-repellent soils have a potential as alternative construction materials that will improve conventional geotechnical structures. In this study, the potential of chemically treated water-repellent kaolin clay as a landfill cover material is explored by examining its characteristics including hydraulic and mechanical properties. In order to provide water repellency to the kaolin clay, the surface of clay particle is modified with organosilanes in concentrations (CO) ranging from 0.5% to 10% by weight. As the CO increases, the specific gravity of treated clay tends to decrease, whereas the total organic carbon content of the treated clay tends to increase. The soil-water contact angle increases with an increase in CO until CO = 2.5%, and then maintains an almost constant value (≈134.0°). Resistance to water infiltration is improved by organosilane treatment under low hydrostatic pressure. However, water infiltration resistance under high hydrostatic pressure is reduced or exacerbated to the level of untreated clay. The maximum compacted dry weight density decreases with increasing CO. As the CO increases, the small strain shear modulus increases, whereas the effect of organosilane treatment on the constrained modulus is minimal. The results indicate that water-repellent kaolin clay possesses excellent engineering characteristics for a landfill cover material. PMID:28774098

Iguana bites reported to Texas poison centers.

Science.gov (United States)

Forrester, Mathias B

2010-09-01

Although thousands of iguanas are kept as pets in the United States, information on their bites is limited. The intent of this investigation was to describe the pattern of iguana bites reported to Texas poison centers. Iguana bites reported during 1998-2008 were identified. The distribution of cases by various factors was determined. Of 59 total bites, 71% were managed on-site, 17% of the patients were at or en route to a health care facility when the poison center was contacted, and 10% were referred to a health care facility. The medical outcome was no effect in 9% of the cases, minor effect in 24%, moderate effect in 2%, not followed but minimal effects possible in 64%, and unable to follow but potentially toxic in 2%. Most iguana bites reported to Texas poison centers did not result in serious effects and were managed on-site. Copyright © 2010 Elsevier Inc. All rights reserved.

Creams formulated with Ocimum gratissimum L. and Lantana camara L. crude extracts and fractions as mosquito repellents against Aedes aegypti L. (Diptera: Culicidae).

Science.gov (United States)

Keziah, Ezeike Amarachi; Nukenine, Elias Nchiwan; Danga, Simon Pierre Yinyang; Younoussa, Lame; Esimone, Charles Okechukwu

2015-01-01

Mosquitoes are the most deadly vectors of parasites that cause diseases such as malaria, yellow fever, and filariasis. In view of the recent increased interest in developing plant origin insecticides as an alternative to chemical insecticides, the objective of this study was to determine the repellent activity of creams formulated with methanol crude extract (MCE), hexane fraction (HF), and ethyl acetate fractions (EAFs) of Ocimum gratissimum and Lantana camara leaves in single and combined actions against female Aedes aegypti. Evaluation was carried out in the net cages (30 by 30 by 30 cm) containing 60 blood-starved female mosquitoes each and were assayed in the laboratory condition following World Health Organization 2009 protocol. All formulations (single and mixture) were applied at 2, 4, 6, and 8 mg/cm(2) in the exposed area of human hands. Only acetone + white soft paraffin served as negative control and odomos (12% DEET) as positive control. All the formulations presented good protection against mosquito bites without any allergic reaction by the human volunteers. The repellent activity was dependent on the strength of the extracts and fractions. Among the tested formulations, the maximum protection time was observed in MCE (120 min) and EAF (150 min) of O. gratissimum; MCE:MCE (150 min) and HF:HF (120 min) mixtures of both plants. In addition, MCE:MCE and HF:HF mixtures from both plants showed possible synergistic effect. From the results, the combination of O. gratissimum and L. camara to formulate natural mosquito repellent using small amount of extracts can be encouraging to be an alternative to conventional DEET. © The Author 2015. Published by Oxford University Press on behalf of the Entomological Society of America.

Age-related changes in the propensity of dogs to bite.

Science.gov (United States)

Messam, L L McV; Kass, P H; Chomel, B B; Hart, L A

2013-08-01

This retrospective cohort study was aimed at describing the effects of age at acquisition, age, and duration of ownership of dogs on the risk of (1) bites during play and (2) non-play bites to humans. Data were collected on 110 dogs that had bitten during play with a person, 161 dogs that had bitten outside of play and 951 non-biting dogs from veterinary clients in Kingston (KGN), Jamaica and San Francisco (SF), USA. Modified Poisson regression was employed to model the relationships of both types of bites to each variable separately. Effects of the variables on dog bite risk (1) during and (2) outside of play with the dog, differed from each other and by type of bite. Effects varied with the dog's age and age-related associations were strongest in dogs younger than 1 year old. Ages at acquisition of dogs at highest risk for bites during play were substantially lower than those at risk for non-play bites. Ages and durations of ownership of dogs at highest risk for bites during play were also lower than those of dogs at highest risk for non-play bites. The propensity of a dog to bite changes as it ages and relationships between dog bites occurring during and outside of play and the dog's age at acquisition, current age, and duration of ownership, differ from each other. Copyright © 2013 Elsevier Ltd. All rights reserved.

First Pediatric Case of Tularemia after a Coyote Bite

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Bruno B. Chomel

2016-01-01

Full Text Available Bite-transmitted tularemia is a rare event in humans and most of the cases have been associated with cat bites. We report the first pediatric case of tularemia caused by a coyote (Canis latrans bite. Coyotes can be healthy carriers of Francisella tularensis and transmit this infectious agent through a bite. Pediatricians should be aware of this risk after a carnivore bite and implement appropriate antibiotic therapy, as amoxicillin/clavulanate potassium (Augmentin may have prolonged the typical two to three days’ incubation period commonly observed for tularemia after an animal bite and was not effective in preventing clinical signs in this child. Finally, it emphasizes again the importance of early and late serum samples for appropriate serodiagnostic.

The salivary secretome of the biting midge, Culicoides sonorensis

Directory of Open Access Journals (Sweden)

Christopher J. Lehiy

2014-06-01

Full Text Available Culicoides biting midges (Diptera: Ceratopogonidae are hematophagous insects with over 1400 species distributed throughout the world. Many of these species are of particular agricultural importance as primary vectors of bluetongue and Schmallenberg viruses, yet little is known about Culicoides genomics and proteomics. Detailed studies of members from other blood-feeding Dipteran families, including those of mosquito (Culicidae and black fly (Simuliidae, have shown that protein components within the insect’s saliva facilitate the blood feeding process. To determine the protein components in Culicoides sonorensis midges, secreted saliva was collected for peptide sequencing by tandem mass spectrometry. Forty-five secreted proteins were identified, including members of the D7 odorant binding protein family, Kunitz-like serine protease inhibitors, maltase, trypsin, and six novel proteins unique to C. sonorensis. Identifying the complex myriad of proteins in saliva from blood-feeding Dipteran species is critical for understanding their role in blood feeding, arbovirus transmission, and possibly the resulting disease pathogenesis.

First report of clinical presentation of a bite by a running spider, Philodromus sp. (Araneae: Philodromidae), with recommendations for spider bite management.

Science.gov (United States)

Coetzee, Maureen; Dippenaar, Ansie; Frean, John; Hunt, Richard H

2017-06-30

This article describes the clinical progression of symptoms over a period of 5 days of a bite inflicted by a Philodromus sp. spider. Commonly known as 'running spiders', these are not considered to be harmful to humans. This report, however, is the first description of an actual bite by a member of this group of spiders showing cytotoxic envenomation. Management of the bites should be as recommended for other cytotoxic spider bites.

[Studies on reduction of repellent force of rare earth magnets--concerning tooth intrusion].

Science.gov (United States)

Kitsugi, A

1992-12-01

The purpose of this investigation was to evaluate the sealing effect of the repelling force of the magnets with ferromagnetic stainless steel and also to examine the reduction pattern along with the change of the relative position of the magnets. The Nd-Fe-B magnet as rare earth magnet, and SUSXM 27, YEP-3, SUS 416 as ferromagnetic stainless steel were used in this experiment. The findings were as follows: 1. There was a little decrease of the repelling force of the magnets sealed with ferromagnetic stainless steel. On the other hand, no significant differences in the repelling force sealed with any kind of ferromagnetic stainless steel were found. 2. Direct contact of the repelling force of the phi 4.0 x 1.5 mm magnets sealed with SUSXM 27 of 0.2 mm in thickness was 242 gf. According to relative horizontal 1.2 mm movement keeping direct contact, the vertical and horizontal components of the repelling force were of the same value. 3. The repelling force of the phi 10.0 x 1.8 mm magnets sealed with SUSXM 27 of 0.2 mm in thickness was 815 gf. It showed more than 300 gf of vertical component of the repelling force when the magnets shifted to 3.0 mm horizontally when in contact. 4. It is suggested that the repelling force of the Nd-Fe-B magnets will be clinically useful for the intrusion of molar teeth.

Bite force and occlusal stress production in hominin evolution.

Science.gov (United States)

Eng, Carolyn M; Lieberman, Daniel E; Zink, Katherine D; Peters, Michael A

2013-08-01

Maximum bite force affects craniofacial morphology and an organism's ability to break down foods with different material properties. Humans are generally believed to produce low bite forces and spend less time chewing compared with other apes because advances in mechanical and thermal food processing techniques alter food material properties in such a way as to reduce overall masticatory effort. However, when hominins began regularly consuming mechanically processed or cooked diets is not known. Here, we apply a model for estimating maximum bite forces and stresses at the second molar in modern human, nonhuman primate, and hominin skulls that incorporates skeletal data along with species-specific estimates of jaw muscle architecture. The model, which reliably estimates bite forces, shows a significant relationship between second molar bite force and second molar area across species but does not confirm our hypothesis of isometry. Specimens in the genus Homo fall below the regression line describing the relationship between bite force and molar area for nonhuman anthropoids and australopiths. These results suggest that Homo species generate maximum bite forces below those predicted based on scaling among australopiths and nonhuman primates. Because this decline occurred before evidence for cooking, we hypothesize that selection for lower bite force production was likely made possible by an increased reliance on nonthermal food processing. However, given substantial variability among in vivo bite force magnitudes measured in humans, environmental effects, especially variations in food mechanical properties, may also be a factor. The results also suggest that australopiths had ape-like bite force capabilities. Copyright © 2013 Wiley Periodicals, Inc.

Repellent Effect and Insecticidal Activities of Bridelia ferruginea, Blighia sapida, and Khaya senegalensis Leaves Powders and Extracts against Dinoderus porcellus in Infested Dried Yam Chips

Directory of Open Access Journals (Sweden)

Laura Yêyinou Loko

2017-01-01

Full Text Available Dinoderus porcellus is considered as the most important pest of stored yam chips and compounds extracted from plants can be used for its control. The present study aimed to test the insecticidal and repellent activities of powders and extracts of leaves of Bridelia ferruginea, Blighia sapida, and Khaya senegalensis against D. porcellus. The efficacy of plant powders was compared with the synthetic pesticide Antouka (Permethrin 3 g/kg + pirimiphos 16 g/kg. The results of the experiment revealed that all plant powders were effective as repellents. Antouka was more effective as insecticidal than the plant powders and minimal weight loss was observed with B. sapida at 2%. Among treatments, propanol extract of K. senegalensis at 5% was found to elicit the highest repellent effect on D. porcellus. The LC50 results revealed that the acetone extract of K. senegalensis is the most toxic (0.29 μL/insect to the pest, while the propanol extract of B. ferruginea at 5% exhibited strong fumigant toxicity against D. porcellus, with 88.89% of pest mortality at 160 μL/L air. The findings from the current work proved that plant powders and extracts of the three plants are sources of botanical insecticides which may be used in the integrated management of D. porcellus.

Application of Super-Hydrophobic Coating for Enhanced Water Repellency of Ballistic Fabric

Energy Technology Data Exchange (ETDEWEB)

Smith, Barton [ORNL; Rajic, Slobodan [ORNL; Hunter, Scott Robert [ORNL

2014-10-01

The objective of this work was to demonstrate that a superhydrophobic coating technology developed at Oak Ridge National Laboratory (ORNL) increases the water repellency of ballistic fabric beyond that provided by existing water repellency treatments. This increased water repellency has the potential to provide durable ballistic fabric for body armor without adding significant weight to the armor or significant manufacturing cost. Specimens of greige and scoured ballistic fabric were treated with a superhydrophobic coating and their weights and degree of water repellency were compared to specimens of untreated fabric. Treatment of both greige and scoured ballistic fabrics yielded highly water repellent fabrics. Our measurements of the water droplet contact angles gave values of approximately 150 , near the lower limit of 160 for superhydrophobic surfaces. The coatings increased the fabric weights by approximately 6%, an amount that is many times less than the estimated weight increase in a conventional treatment of ballistic fabric. The treated fabrics retained a significant amount of water repellency following a basic abrasion test, with water droplet contact angles decreasing by 14 to 23 . Microscopic analysis of the coating applied to woven fabrics indicated that the coating adhered equally well to fibers of greige and scoured yarns. Future evaluation of the superhydrophobic water repellent treatment will involve the manufacture of shoot packs of treated fabric for ballistic testing and provide an analysis of manufacturing scale-up and cost-to-benefit considerations.

Repellent Activity of Apiaceae Plant Essential Oils and their Constituents Against Adult German Cockroaches.

Science.gov (United States)

Lee, Hyo-Rim; Kim, Gil-Hah; Choi, Won-Sil; Park, Il-Kwon

2017-04-01

We evaluated the repellent activity of 12 Apiaceae plant essential oils and their components against male and female adult German cockroaches, Blattella germanica L., to find new natural repellents. Of all the plant essential oils tested, ajowan (Trachyspermum ammi Sprague) and dill (Anethum graveolens L.) essential oils showed the most potent repellent activity against male and female adult German cockroaches. Repellent activities of chemicals already identified in active oils were also investigated. Of the compounds identified, carvacrol, thymol, and R-(-)-carvone showed >80% repellent activity against male and female adult German cockroaches at 2.5 µg/cm2. S-(+)-Carvone, (+)-dihydrocarvone, and terpinen-4-ol showed >70% repellent activity against male and female adult German cockroaches at 10 µg/cm2. Our results indicated that Apiaceae plant essential oils and their constituents have good potential as natural repellents against adult German cockroaches. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

K-9 Police Dog Bite

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Vy Han

2017-01-01

Full Text Available History of present illness: A 30-year-old male who was brought into the emergency department (ED by police officers after being bitten in the right lower extremity by a police German Shepard after attempting to flee authorities on foot. The patient stated that the dog immediately bit down on his right calf and proceeded to violently shake its head side to side without releasing its grip until police manually pulled the dog off of him. Upon arrival to the ED, he was tachycardic in the 120’s, complaining of severe, throbbing, sharp pain in the right lower extremity, and was neurovascular intact on exam. Significant findings: The photograph is of the anterior compartment of the right lower leg demonstrating multiple deep lacerations with exposed and torn muscle. X-ray showed no foreign body. Discussion: Police dog bites should be treated more cautiously than typical dog bites because these highly-trained dogs are generally larger breeds which are taught to subdue suspects with a bite-and-hold technique rather than bite and release. This can lead to extensive crush injuries, fractures, large caliber lacerations with associated muscle tissue injury and/or severe neurovascular compromise.1 Hence, police dog bites often require provocative diagnostic testing, specialist consultation for possible operative repair, and aggressive irrigation and ultimately admission for intravenous antibiotics.1 This patient’s wound was aggressively irrigated and evaluated by plastic surgery in the ED. He was ultimately admitted for intravenous antibiotics, pain control, wound care, and healing by secondary intention.

Treatment of horses with cypermethrin against the biting flies Culicoides nubeculosus, Aedes aegypti and Culex quinquefasciatus.

Science.gov (United States)

Papadopoulos, E; Rowlinson, M; Bartram, D; Carpenter, S; Mellor, P; Wall, R

2010-04-19

An in vitro assay was used to assess the efficacy of the proprietary pyrethroid insecticide cypermethrin applied to horses (Deosect spray, 5.0%, w/v Fort Dodge Animal Health) against the biting midge Culicoides nubeculosus (Meigen) (Diptera: Ceratopogonidae) and the mosquitoes Aedes aegypti Linneaus and Culex quinquefasciatus Say (Diptera: Culicidae). Hair was collected from the back, belly and legs of the horses immediately prior to treatment and 7, 14, 21, 28 and 35 days after treatment, and also from untreated controls. In laboratory assays groups of 10 adult female C. nubeculosus, Ae. aegypti or C. quinquefasciatus were exposed to 0.5g of hair for 3min. In all cases, little or no mortality was observed in insects kept in contact with the pre-treatment samples or the untreated controls. With post-treatment samples for C. nubeculosus, mortality was close to 80% 7 days after treatment and then declined gradually; mean mortality was still at around 50% for hair collected 35 days after treatment. In general, Ae. aegypti and C. quinquefasciatus appeared to be less susceptible to cypermethrin than C. nubeculosus and the attenuation of the toxic effect declined more quickly with time after treatment. There were differences in the toxicity of hair from different body regions, with hair from the back consistently inducing the highest mortality and hair from the legs the lowest; this effect was more pronounced for C. nubeculosus than Ae. aegypti or C. quinquefasciatus. The results demonstrate the potential for topical insecticide treatment to offer protection to horses against biting flies; but highlight the major differences that exist in susceptibility between different insect species.

Managing Rocky Mountain spotted fever.

Science.gov (United States)

Minniear, Timothy D; Buckingham, Steven C

2009-11-01

Rocky Mountain spotted fever is caused by the tick-borne bacterium Rickettsia rickettsii. Symptoms range from moderate illness to severe illness, including cardiovascular compromise, coma and death. The disease is prevalent in most of the USA, especially during warmer months. The trademark presentation is fever and rash with a history of tick bite, although tick exposure is unappreciated in over a third of cases. Other signature symptoms include headache and abdominal pain. The antibiotic therapy of choice for R. rickettsii infection is doxycycline. Preventive measures for Rocky Mountain spotted fever and other tick-borne diseases include: wearing long-sleeved, light colored clothing; checking for tick attachment and removing attached ticks promptly; applying topical insect repellent; and treating clothing with permethrin.

Rat bite fever in a pet lover.

Science.gov (United States)

Cunningham, B B; Paller, A S; Katz, B Z

1998-02-01

Rat-bite fever is an uncommon bacterial illness resulting from infection with Streptobacillus moniliformis that is often transmitted by the bite of a rat. The cutaneous findings in rat-bite fever are nonspecific but have been described as maculopapular or petechial. We describe a 9-year-old girl with acrally distributed hemorrhagic pustules, fever, and arthralgias. Diagnosis was delayed because of difficulty in identifying the pathologic organism. She was successfully treated with 10 days of ceftriaxone.

Factors Associated with Tick Bite Preventive Practices among Farmworkers in Malaysia

Science.gov (United States)

Wong, Li Ping; Tay, Sun Tee; Bulgiba, Awang; Zandi, Keivan; Kho, Kai Ling; Koh, Fui Xian; Ong, Bee Lee; Jaafar, Tariq; Hassan Nizam, Quaza Nizamuddin

2016-01-01

Background Farmworkers are at high-risk for tick bites, which potentially transmit various tick-borne diseases. Previous studies show that personal prevention against tick bites is key, and certain factors namely, knowledge, experience of tick bites, and health beliefs influence compliance with tick bites preventive behaviour. This study aimed to assess these factors and their associations with tick bite preventive practices among Malaysian farmworkers. Methods A total of eight cattle, goat and sheep farms in six states in Peninsular Malaysia participated in a cross-sectional survey between August and October 2013 Results A total of 151 (72.2%) out of 209 farmworkers answered the questionnaire. More than half of the farmworkers (n = 91) reported an experience of tick bites. Farms with monthly acaricide treatment had significantly (P<0.05) a low report of tick bites. Tick bite exposure rates did not differ significantly among field workers and administrative workers. The mean total knowledge score of ticks for the overall farmworkers was 13.6 (SD±3.2) from 20. The mean total tick bite preventive practices score for all farmworkers was 8.3 (SD±3.1) from 15. Fixed effect model showed the effects of four factors on tick bite prevention: (1) farms, (2) job categories (administrative workers vs. field workers), (3) perceived severity of tick bites, and (4) perceived barriers to tick bite prevention. Conclusions A high proportion of farmworkers, including administrative workers, reported an experience of tick bites. The effectiveness of monthly acaricide treatment was declared by low reports of tick bites on these farms. Tick bite preventive practices were insufficient, particularly in certain farms and for administrative workers. Our findings emphasise the need to have education programmes for all farmworkers and targeting farms with low prevention practices. Education and health programmes should increase the perception of the risk of tick bites and remove perceived

A qualitative investigation of the perceptions of female dog-bite victims and implications for the prevention of dog bites

OpenAIRE

Westgarth, Carri; Watkins, Francine

2015-01-01

Preventing dog bites is an increasingly important public health and political issue with implications for both human and animal health and welfare. Expert opinion is that most bites are preventable. Intervention materials have been designed to educate people on how to assess the body language of dogs, evaluate risk, and take appropriate action. The effectiveness of this approach is rarely evaluated and the incidence of dog bites is thought to be increasing. Is the traditional approach to dog ...

Human behavior preceding dog bites to the face.

Science.gov (United States)

Rezac, P; Rezac, K; Slama, P

2015-12-01

Facial injuries caused by dog bites pose a serious problem. The aims of this study were to determine human behavior immediately preceding a dog bite to the face and to assess the effects of victim age and gender and dog sex and size on the location of the bite to the face and the need for medical treatment. Complete data on 132 incidents of bites to the face were analysed. A human bending over a dog, putting the face close to the dog's face, and gazing between victim and dog closely preceded a dog bite to the face in 76%, 19% and 5% of cases, respectively. More than half of the bites were directed towards the central area of the victim's face (nose, lips). More than two thirds of the victims were children, none of the victims was an adult dog owner and only adult dogs bit the face. Victim's age and gender and dog's sex and size did not affect the location of the bite on the face. People who were bitten by large dogs sought medical treatment more often than people who were bitten by small dogs (P face close to the dog's face and gazing between human and dog should be avoided, and children should be carefully and constantly supervised when in the presence of dogs. Copyright © 2015 Elsevier Ltd. All rights reserved.

Experimental Investigation of Evaporation and Drainage in Wettable and Water-Repellent Sands

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Dae Hyun Kim

2015-05-01

Full Text Available This study presents experimental results on evaporation and drainage in both wettable and water-repellent sands whose surface wettability was artificially modified by silanization. The 2D optical and 3D X-ray computed tomographic imaging was performed during evaporation and the water retention during cyclic drainage and infiltration was measured to assess effects of wettability and initial wetting conditions. The evaporation gradually induces its front at the early stage advance regardless of the wettability and sand types, while its rate becomes higher in water-repellent Ottawa sand than the wettable one. Jumunjin sand which has a smaller particle size and irregular particle shape than Ottawa sand exhibits a similar evaporation rate independent of wettability. Water-repellent sand can facilitate the evaporation when both wettable and water-repellent sands are naturally in contact with each other. The 3D X-ray imaging reveals that the hydraulically connected water films in wettable sands facilitate the propagation of the evaporation front into the soil such that the drying front deeply advances into the soil. For cyclic drainage-infiltration testing, the evolution of water retention is similar in both wettable and water-repellent sands when both are initially wet. However, when conditions are initially dry, water-repellent sands exhibit low residual saturation values. The experimental observations made from this study propose that the surface wettability may not be a sole factor while the degree of water-repellency, type of sands, and initial wetting condition are predominant when assessing evaporation and drainage behaviors.

Injurious tail biting in pigs

DEFF Research Database (Denmark)

D'Eath, R.B.; Amott, G.; Turner, S. P.

2014-01-01

not allow tail docking at all. Against this background, using a novel approach focusing on research where tail injuries were quantified, we review the measures that can be used to control tail biting in pigs without tail docking. Using this strict criterion, there was good evidence that manipulable...... substrates and feeder space affect damaging tail biting. Only epidemiological evidence was available for effects of temperature and season, and the effect of stocking density was unclear. Studies suggest that group size has little effect, and the effects of nutrition, disease and breed require further...... underlying processes of tail biting. A quantitative comparison of the efficacy of different methods of provision of manipulable materials, and a review of current practices in countries and assurance schemes where tail docking is banned, both suggest that daily provision of small quantities of destructible...

Repelência e deterrência na oviposição de Bemisia tabaci biótipo B pelo uso de extratos vegetais em Cucurbita pepo L Repellence and deterrence on oviposition of Bemisia tabaci biotype B by the use of vegetal extracts in Cucurbita pepo L

Directory of Open Access Journals (Sweden)

J.P.G.F. Silva

2012-01-01

, T. pallida (leaves, A. indica (almonds, Chenopodium ambrosioides L. (inflorescence + leaves + branches and Mentha pulegium L. (leaves on Bemisia tabaci biotype B in squash, by assays of repellence and oviposition deterrence. In free choice tests, the attractiveness and determination of the rate of repellence (with 6, 24 and 48 hours after application of the extracts were evaluated. The oviposition was observed after the third counting of the number of adults. The extract of leaves of M. pulegium showed repellence and oviposition deterrence to B. tabaci biotype B and may be recommended as an alternative in the insect management.

Repellent activity of monoterpenoid esters with neurotransmitter amino acids against yellow fever mosquito, Aedes aegypti

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Nesterkina Mariia

2018-03-01

Full Text Available Repellent activity of monoterpenoid esters (1-6 with neurotransmitter amino acids (GABA and glycine was investigated against Aedes aegypti by using a “cloth-patch” assay and compared to reference standard N,N-diethyl-3-methylbenzamide (DEET. Monoterpenoid esters showed repellent activity with minimum effective dosages (MED in the range of 0.031-0.469 mg/cm2. The carvacrol ester of GABA (2, MED of 0.031 ± 0.008 mg/cm2 exhibited the highest repellency of six monoterpenoid esters tested in comparison to the standard repellent DEET (MED of 0.009 ± 0.002 mg/cm2; however, the repellent activity of carvacrol-glycine ester (5 decreased 4-fold compared to the carvacrol-GABA derivative (2. The repellent activities of menthol GABA (1, MED= 0.375 ± 0.000 mg/cm2 and glycine ester (4, MED=0.312 ± 0.063 mg/cm2 were similar The guaiacol-glycine ester (6 was 3.75-fold more efficacious than the guaiacol ester of GABA (3. In the present study, we report repellent efficacy of prolonged exposure to GABA and glycine esters of menthol, carvacrol, guaiacol (1-6 as compared to the repellent activities of their monoterpene moieties alone.

Fighting and Biting

Science.gov (United States)

... on Demand Maintenance of Certification and Lifelong Learning Modules Online CME Pathways My Profile Store Cart Donate ... child, or put the child down. For a young child (2-3 years) say, "biting is not ...

Potential of Eucalyptus Oil as Repellent against House Rat, Rattus rattus

Science.gov (United States)

Thind, Ramandeep Kaur; Mahal, Amrit Kaur

2014-01-01

Rodent repellents are chemicals which by taste or odour or possibly by both will prevent animal from feeding or gnawing. Such substances may be used in protecting an area from rodent infestation or in protecting packaged food, packing materials, electric cables, and other important vulnerable materials. Mature and healthy house rat, Rattus rattus of both sexes, was exposed to 5, 10, and 20% eucalyptus oil applied as spray in laboratory pens in bichoice tests. Each concentration was applied through three different modes of application, that is, daily, once, and alternatively in a week. Repellent effect of the oil was assessed based on food consumption from treated and untreated sides for four days. In overall, food consumption was significantly (P eucalyptus oil. Present studies reveal the potential of eucalyptus oil in repelling away R. rattus; however, further studies may be conducted to enhance the persistence of repellent effect for longer period of time. PMID:24523633

Sensitivity to bites by the bedbug, Cimex lectularius.

Science.gov (United States)

Reinhardt, K; Kempke, D; Naylor, R A; Siva-Jothy, M T

2009-06-01

Bedbugs are a public health problem and can cause significant economic losses, but little is known about the effects of bites on humans. We reviewed case reports and published papers on bedbug bites to assess the empirical basis of the commonly cited figure that only approximately 80% of the population are sensitive to bedbug bites. We found the sensitivity estimate to be based on only one study carried out 80 years ago. However, this study did not account for the now well-established fact that only repeated exposure to external allergens leads to skin reactions. In our sample, 18 of 19 persons showed a skin reaction after bedbug exposure, but in most cases only after repeated controlled exposure. With repeated exposure, the latency between bite and skin reactions decreased from approximately 10 days to a few seconds. Our results are relevant for the hospitality industry, where apparently increasing infestation rates are likely to lead to an increase in the number of tourists and hotel employees exposed to bedbugs. Medical and public health professionals may expect to see an increase in the prevalence of people with bedbug bite sensitivity. The significance of the delayed reaction time of skin to bites may also have implications in litigation cases where people seek compensation.

Comparative study of the topical effectiveness of the andiroba oil (Carapa guianensis and DEET 50% as repellent for Aedes sp Estudo comparativo da eficácia tópica do óleo de andiroba (Carapa guianensis e DEET 50% como repelente para Aedes sp

Directory of Open Access Journals (Sweden)

Hélio Amante Miot

2004-10-01

Full Text Available DEET (N,N-diethyl-3-methylbenzamide is nowadays the most effective mosquito repellent available, however, its use can present some topical and systemic side effects. Some botanical compositions, as Andiroba (Carapa guianensis, have been proved repellent properties at low cost and toxicity. An experimental study was driven involving four volunteers submitting their forearms covered with Andiroba oil at 100%, DEET 50%, refined soy oil, Andiroba oil 15% and in the absence of products, directly to healthy females of Aedes sp. The times of first and third bites were checked. The results showed that the median of the first bite without any product was 17.5s and the third bite, 40.0s. In the soy oil, the bites happened in 60.0s and 101.5s, in the presence of Andiroba oil 100%, in 56.0s and 142.5s and in Andiroba oil 15%, in 63.0s and 97.5s. The volunteers using DEET 50% had not received bites after 3600s in most of the experiments (p O DEET (N, N-dietil-3-metilbenzamida é hoje o repelente mais efetivo disponível, porém, seu uso pode apresentar importantes efeitos colaterais tópicos e sistêmicos. Alguns compostos botânicos, como a Andiroba (Carapa guianensis, têm demonstrado propriedades repelentes a um baixo custo e baixa toxicidade. Quatro voluntários hígidos submeteram seus antebraços recobertos com óleo de Andiroba a 100%, DEET 50% (controle positivo, óleo de soja refinado, óleo de Andiroba 15% e na ausência de produtos (controles negativos, diretamente a picadas de fêmeas saudáveis de Aedes sp. Foram aferidos os tempos da primeira e terceira picadas. Os resultados mostraram que a mediana da primeira picada nos antebraços sem produto foi 17.5s e a terceira picada, 40.0s. No óleo de soja, as picadas ocorreram em 60.0s e 101.5s. No óleo de Andiroba 100%, em 56.0s e 142.5s. Com Andiroba 15%, em 63.0s e 97.5s. Usando DEET 50% não houve picadas após 3600s na maioria dos experimentos (p < 0.001 Wilcoxon. O óleo de Andiroba 100

[Prevalence of cross-bite in Mexican children].

Science.gov (United States)

Ojeda León, S; De la Teja Angeles, E

1990-10-01

As observed, the problem of lining and accommodation of teeth in the child population is increasingly larger. This fact prompted the authors to attempt determining the prevalence of cross-bite in a sample of Mexican children. A total of 306 patients, aged between two and 17 and attending the Stomatology service of the National Institute of Pediatrics, were evaluated, from which all pertinent data regarding age, sex, molar-temporal relationship (terminal, rectus, distal, messial and exaggerated messial planes), permanent molar status (Angle I, II, III), cross-bite, type of dentition affected (primary, mixed or permanent), cross-bite classification (anterior, posterior or mixed), whether unilateral, bilateral, dental or skeletal, right or left, and number of teeth affected, were duly recorded. Out of 306 evaluated patients (160 males, 146 female), 112 evidenced cross-bite (36.6%), 56 of each sex; in 69.6% the teeth were anterior, in 17.8% they were posterior, and in 15.5% their position was mixed. Their average age was 8 years, and malocclusion was Angle class I. From this experience, it is to be concluded that early detection and correction of any dental occlusion abnormality will permit correcting defects in dentofacial development; it is thus necessary to ascertain the frequency of cross-bite.

Defensive Metabolites from Antarctic Invertebrates: Does Energetic Content Interfere with Feeding Repellence?

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Laura Núñez-Pons

2014-06-01

Full Text Available Many bioactive products from benthic invertebrates mediating ecological interactions have proved to reduce predation, but their mechanisms of action, and their molecular identities, are usually unknown. It was suggested, yet scarcely investigated, that nutritional quality interferes with defensive metabolites. This means that antifeedants would be less effective when combined with energetically rich prey, and that higher amounts of defensive compounds would be needed for predator avoidance. We evaluated the effects of five types of repellents obtained from Antarctic invertebrates, in combination with diets of different energetic values. The compounds came from soft corals, ascidians and hexactinellid sponges; they included wax esters, alkaloids, a meroterpenoid, a steroid, and the recently described organic acid, glassponsine. Feeding repellency was tested through preference assays by preparing diets (alginate pearls combining different energetic content and inorganic material. Experimental diets contained various concentrations of each repellent product, and were offered along with control compound-free pearls, to the Antarctic omnivore amphipod Cheirimedon femoratus. Meridianin alkaloids were the most active repellents, and wax esters were the least active when combined with foods of distinct energetic content. Our data show that levels of repellency vary for each compound, and that they perform differently when mixed with distinct assay foods. The natural products that interacted the most with energetic content were those occurring in nature at higher concentrations. The bioactivity of the remaining metabolites tested was found to depend on a threshold concentration, enough to elicit feeding repellence, independently from nutritional quality.

Defensive Metabolites from Antarctic Invertebrates: Does Energetic Content Interfere with Feeding Repellence?

Science.gov (United States)

Núñez-Pons, Laura; Avila, Conxita

2014-01-01

Many bioactive products from benthic invertebrates mediating ecological interactions have proved to reduce predation, but their mechanisms of action, and their molecular identities, are usually unknown. It was suggested, yet scarcely investigated, that nutritional quality interferes with defensive metabolites. This means that antifeedants would be less effective when combined with energetically rich prey, and that higher amounts of defensive compounds would be needed for predator avoidance. We evaluated the effects of five types of repellents obtained from Antarctic invertebrates, in combination with diets of different energetic values. The compounds came from soft corals, ascidians and hexactinellid sponges; they included wax esters, alkaloids, a meroterpenoid, a steroid, and the recently described organic acid, glassponsine. Feeding repellency was tested through preference assays by preparing diets (alginate pearls) combining different energetic content and inorganic material. Experimental diets contained various concentrations of each repellent product, and were offered along with control compound-free pearls, to the Antarctic omnivore amphipod Cheirimedon femoratus. Meridianin alkaloids were the most active repellents, and wax esters were the least active when combined with foods of distinct energetic content. Our data show that levels of repellency vary for each compound, and that they perform differently when mixed with distinct assay foods. The natural products that interacted the most with energetic content were those occurring in nature at higher concentrations. The bioactivity of the remaining metabolites tested was found to depend on a threshold concentration, enough to elicit feeding repellence, independently from nutritional quality. PMID:24962273

Functional Analysis and Treatment of Nail Biting

Science.gov (United States)

Dufrene, Brad A.; Watson, T. Steuart; Kazmerski, Jennifer S.

2008-01-01

This study applied functional analysis methodology to nail biting exhibited by a 24-year-old female graduate student. Results from the brief functional analysis indicated variability in nail biting across assessment conditions. Functional analysis data were then used to guide treatment development and implementation. Treatment included a…

Vine snake (Thelotornis capensis bite in a dog : clinical communication

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J. Otto

2003-06-01

Full Text Available A vine snake bite in a dog is reported. There was continued minor bleeding from the assumed nose bite site for 4 days. Currently manufactured snakebite antivenom is not effective against vine snake bites and treatment is supportive.

The influence of compost addition on the water repellency of brownfield soils

Science.gov (United States)

Whelan, Amii; Kechavarzi, Cedric; Sakrabani, Ruben; Coulon, Frederic; Simmons, Robert; Wu, Guozhong

2010-05-01

Compost application to brownfield sites, which can facilitate the stabilisation and remediation of contaminants whilst providing adequate conditions for plant growth, is seen as an opportunity to divert biodegradable wastes from landfill and put degraded land back into productive use. However, although compost application is thought to improve soil hydraulic functioning, there is a lack of information on the impact of large amounts of compost on soil water repellency. Water repellency in soils is attributed to the accumulation of hydrophobic organic compounds released as root exudates, fungal and microbial by-products and decomposition of organic matter. It has also been shown that brownfield soils contaminated with petroleum-derived organic contaminants can exhibit strong water repellency, preventing the rapid infiltration of water and leading potentially to surface run off and erosion of contaminated soil. However, hydrophobic organic contaminants are known to become sequestrated by partitioning into organic matter or diffusing into nano- and micropores, making them less available over time (ageing). The effect of large amounts of organic matter addition through compost application on the water repellency of soils contaminated with petroleum-derived organic contaminants requires further investigation. We characterised the influence of compost addition on water repellency in the laboratory by measuring the Water Drop Penetration Time (WDPT), sorptivity and water repellency index through infiltration experiments on soil samples amended with two composts made with contrasting feedstocks (green waste and predominantly meat waste). The treatments consisted of a sandy loam, a clay loam and a sandy loam contaminated with diesel fuel and aged for 3 years, which were amended with the two composts at a rate equivalent to 750t/ha. In addition core samples collected from a brownfield site, amended with compost at three different rates (250, 500 and 750t/ha) in 2007, were

prevalence of biting and non-biting flies in relation to species

African Journals Online (AJOL)

USER

The biting effects on resident animals and ... and second largest tourist destination in Nigeria will require concerted efforts to put in proper ... hosts from pool of available susceptible hosts (Okoth ..... communities of the lower Cross River Basin.

An Analytical Study of Mammalian Bite Wounds Requiring Inpatient Management

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Young-Geun Lee

2013-11-01

Full Text Available BackgroundMammalian bite injuries create a public health problem because of their frequency, potential severity, and increasing number. Some researchers have performed fragmentary analyses of bite wounds caused by certain mammalian species. However, little practical information is available concerning serious mammalian bite wounds that require hospitalization and intensive wound management. Therefore, the purpose of this study was to perform a general review of serious mammalian bite wounds.MethodsWe performed a retrospective review of the medical charts of 68 patients who were referred to our plastic surgery department for the treatment of bite wounds between January 2003 and October 2012. The cases were analyzed according to the species, patient demographics, environmental factors, injury characteristics, and clinical course.ResultsAmong the 68 cases of mammalian bite injury, 58 (85% were caused by dogs, 8 by humans, and 2 by cats. Most of those bitten by a human and both of those bitten by cats were male. Only one-third of all the patients were children or adolescents. The most frequent site of injury was the face, with 40 cases, followed by the hand, with 16 cases. Of the 68 patients, 7 were treated with secondary intention healing. Sixty-one patients underwent delayed procedures, including delayed direct closure, skin graft, composite graft, and local flap.ConclusionsBased on overall findings from our review of the 68 cases of mammalian bites, we suggest practical guidelines for the management of mammalian bite injuries, which could be useful in the treatment of serious mammalian bite wounds.

Evaluation of the repellent and insecticidal activities of the leaf, stem ...

African Journals Online (AJOL)

Adults of C. maculatus were exposed to grains treated separately with the root, stem and leaf powders of C. odorata at different exposure periods of 12, 24, 36, and 48 hours. All the three plant parts significantly repelled C. maculatus with the root powder showing the highest percentage repellency, although this was a ...

Animal Bites in Borujerd: An Overview of Animal Bites in Iran

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Sabouri Ghannad

2014-04-01

Full Text Available Background Rabies has been reported as the most important endemic zoonotic disease in Iran and still remains as a major public health problem. Objectives The main objective of the current research was to study the epidemiology of animal bites in Borujerd County in Iran and to compare its prevalence to other parts of Iran from April 2006 to September 2011. Patients and Methods The data were recorded in questionnaires and analyzed by SPSS version 16. Chi-square test was performed to evaluate the relationship among variables and P value was set as 0.05. Results Dog bites were the most common (69.8%, followed by cat (17.2%, fox and wolf (1.4%, sheep and cow (2.8%, monkey and donkey (5%, mouse and squirrel (2.2% and other animals (1.6%. Leg was the most common bite site forming 46.6% of cases, followed by hands (41.8%, buttocks (4.6%, head (4% and body (2.9%. Most of the subjects belonged to the age group < 10 (175.2 per 100000 populations. The injury location was associated significantly with sex and the residential status. Conclusions This study strongly highlights a high priority goal for health authorities to develop educational programs, recommended for the general population to inform them about the benefits of continuing the medication. Vaccination of domestic dogs and also eradication of stray ones, in addition to educational programs should be prioritized by health authorities.

Scrotal dog bite: unusual case and review of pediatric literature.

Science.gov (United States)

Bertozzi, M; Prestipino, M; Nardi, N; Falcone, F; Appignani, A

2009-09-01

Animal bites to human external genitalia are rare. Only a few cases of scrotal dog bite in children have been reported. We present an additional specific case of a scrotal dog bite in a child because the lesion and its repair have not been previously reported in published pediatric studies. A traumatic resection of the right testicular vas deferens was repaired by microsurgical vasoepididymal anastomosis. A review of the published data was also performed to analyze the management of scrotal dog bite lesions.

Geographic variation in access to dog-bite care in Pakistan and risk of dog-bite exposure in Karachi: prospective surveillance using a low-cost mobile phone system.

Science.gov (United States)

Zaidi, Syed Mohammad Asad; Labrique, Alain B; Khowaja, Saira; Lotia-Farrukh, Ismat; Irani, Julia; Salahuddin, Naseem; Khan, Aamir Javed

2013-01-01

Dog-bites and rabies are under-reported in developing countries such as Pakistan and there is a poor understanding of the disease burden. We prospectively collected data utilizing mobile phones for dog-bite and rabies surveillance across nine emergency rooms (ER) in Pakistan, recording patient health-seeking behaviors, access to care and analyzed spatial distribution of cases from Karachi. A total of 6212 dog-bite cases were identified over two years starting in February 2009 with largest number reported from Karachi (59.7%), followed by Peshawar (13.1%) and Hyderabad (11.4%). Severity of dog-bites was assessed using the WHO classification. Forty percent of patients had Category I (least severe) bites, 28.1% had Category II bites and 31.9% had Category III (most severe bites). Patients visiting a large public hospital ER in Karachi were least likely to seek immediate healthcare at non-medical facilities (Odds Ratio = 0.20, 95% CI 0.17-0.23, p-valuedog-bites in Karachi suggested clustering of cases (Moran's I = 0.02, p valuedog-bite case reported, or approximately USD 44,408 over two years. Our findings suggest significant differences in access to care and health-seeking behaviors in Pakistan following dog-bites. The distribution of cases in Karachi was suggestive of clustering of cases that could guide targeted disease-control efforts in the city. Mobile phone technologies for health (mHealth) allowed for the operation of a national-level disease reporting and surveillance system at a low cost.

Structural requirements for repellency: norsesquiterpenes and sesquiterpenoid derivatives of nootkatone against the Formosan subterranean termite (Isoptera: Rhinotermitidae).

Science.gov (United States)

Zhu, Betty C R; Henderson, Gregg; Sauer, Anne M; Crowe, William; Laine, Roger A

2010-08-01

Research has shown that the family of grapefruit flavors called nootkatones have significant repellant and toxic effects to Formosan subterranean termites (Coptotermes formosanus Shiraki). Nineteen synthetic nootkatone derivatives, along with three commercially available nootkatone derivatives, were tested for repellent activity against C. formosanus by a choice assay in a petri dish with a two-step triage procedure. Based on the repellency threshold value, the relationships between structure and activity are discussed. Four derivatives of nootkatone have very high repellency and toxicity to C. formosanus, 9 times the potency of the primary compound nootkatone. Four other compounds have between 2 and 3 times the repellency of nootkatones, and three compounds are equal in their repellency to nootkatone. Copyright (c) 2010 Society of Chemical Industry.

The impact of snake bite on household economy in Bangladesh.

Science.gov (United States)

Hasan, S M K; Basher, A; Molla, A A; Sultana, N K; Faiz, M A

2012-01-01

The present study aims to assess the different types of costs for treatment of snake bite patients, to quantify household economic impact and to understand the coping mechanisms required to cover the costs for snake bite patients in Bangladesh. The patients admitted to four tertiary level hospitals in Bangladesh were interviewed using structured questionnaires including health-care-related expenditures and the way in which the expenditures were covered. Of the snakes which bit the patients, 54.2% were non-venomous, 45.8% were venomous and 42.2% of the patients were given polyvalent antivenom. The total expenditure related to snake bite varies from US$4 (US$1 = Taka 72) to US$2294 with a mean of US$124 and the mean income loss was US$93. Expenditure for venomous snake bite was US$231, which is about seven times higher than non-venomous snake bite (US$34). The treatment imposes a major economic burden on affected families, especially in venomous snake bite cases.

Talking to Patients about Preventing Tick Bites

Centers for Disease Control (CDC) Podcasts

2012-02-14

This podcast will help health care providers identify patients who are at increased risk of getting tick bites and provide these patients with tick bite prevention and removal tips.  Created: 2/14/2012 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 2/14/2012.

Factors associated with anterior open bite in children with developmental disabilities.

Science.gov (United States)

de Castilho, Lia Silva; Abreu, Mauro Henrique Nogueira Guimarães; Pires E Souza, Luiz Gustavo de Almeida; Romualdo, Leiliane Teresinha de Almeida; Souza E Silva, Maria Elisa; Resende, Vera Lúcia Silva

2018-01-01

To investigate factors associated with anterior open bite in individuals aged from 2 to 33 years with developmental disabilities. This is a cross-sectional study. A total of 271 dental records were examined. The anterior open bite analyzed was determined based on clinic exam. These variables were also analyzed: gender, age, education level of mother, International Code of Diseases (ICD), mouth breathing, use of anticonvulsant drugs, hyperkinesis, pacifier use, thumb sucking, seizure, and involuntary movements. For the purposes of analysis, the individuals were categorized as being with and without anterior open bite. Variables with a p-value of open bite than nasal breathers. Pacifier users are more likely to have an anterior open bite (3.32-fold, 95% CI: 1.62-6.77). Individuals with reported involuntary movements had a 2.66-fold (95% CI: 1.26-5.63) greater chance of exhibiting anterior open bite. Users of anticonvulsants drugs had a 3.05 (95% CI: 1.57-5.92) greater chance of showing anterior open bite. Involuntary movements, mouth breathing, using anticonvulsant drugs, and using pacifier are factors associated with anterior open bite in patients with developmental disabilities. © 2017 Special Care Dentistry Association and Wiley Periodicals, Inc.

Mosquito bite anaphylaxis: immunotherapy with whole body extracts.

Science.gov (United States)

McCormack, D R; Salata, K F; Hershey, J N; Carpenter, G B; Engler, R J

1995-01-01

Adverse reactions to mosquito bites have been recognized for some time. These usually consist of large local swellings and redness, generalized urticaria, angioedema and less easily definable responses such as nausea, dizziness, headaches, and lethargy. We report two patients who experienced systemic anaphylaxis from mosquito bites. Both were skin tested and given immunotherapy using whole body mosquito extracts. Skin testing using whole body mosquito extracts was positive to Aedes aegypti at 1/1,000 weight/volume (wt/vol) in one patient and to Aedes aegypti at 1/100,000 wt/vol, and Culex pipiens at 1/10,000 wt/vol in the other. Skin testing of ten volunteers without a history of adverse reactions to mosquito bites was negative. Immunotherapy using these extracts resulted in resolution of adverse reactions to mosquito bites in one patient and a decrease in reactions in the other. Immunotherapy with whole body mosquito extracts is a viable treatment option that can play a role in patients with mosquito bite-induced anaphylaxis. It may also result in severe side effects and one must determine the benefit versus risks for each individual patient.

(snail repellent paint) on land snails

African Journals Online (AJOL)

STORAGESEVER

2009-10-19

Oct 19, 2009 ... the above treatments has shown that repellent band and methaldehyde with 5 ± 1.3 and 10.6 ± 0.9 percentage ..... does not readily dissolve in water, which minimizes its dispersal ... limpets and macroalgae, J. Exp. Mar. Biol.

Mosquito repellency of novel Trifluoromethylphenyl amides

Science.gov (United States)

Human diseases caused by mosquito-transmitted pathogens include malaria, dengue and yellow fever and are responsible for several million human deaths every year, according to the World Health Organization (WHO). Our current research projects focus on the development of new insecticides and repellent...

Use of clear aligners in open bite cases: an unexpected treatment option.

Science.gov (United States)

Giancotti, Aldo; Garino, Francesco; Mampieri, Gianluca

2017-06-01

In open bite case treatments, a proper diagnostic differentiation is essential in determining the appropriate corrective procedures. Dental open bites are generally more responsive to treatment with orthodontics alone, whereas skeletal open bites often require a combination of orthodontics and orthognathic surgery. Patient selection and treatment principles for non-surgical open bite treatment routinely include fixed appliances both labial or lingual. However, removable clear aligners have gained a consistent popularity in the treatment of complex cases including open bite malocclusions. In this article, the authors describe three different clinical cases in which open bite cases had been satisfactorily treated by using clear aligners.

Estimation of Dog-Bite Risk and Related Morbidity Among Personnel Working With Military Dogs.

Science.gov (United States)

Schermann, H; Eiges, N; Sabag, A; Kazum, E; Albagli, A; Salai, M; Shlaifer, A

Soldiers serving in the Israel Defense Force Military Working Dogs (MWD) Unit spend many hours taming dogs' special skills, taking them on combat missions, and performing various dogkeeping activities. During this intensive work with the aggressive military dogs, bites are common, and some of them result in permanent disability. However, this phenomenon has not been quantified or reported as an occupational hazard. This was a retrospective cohort study based on self-administered questionnaires. Information was collected about soldiers' baseline demographics, duration of the experience of working with dogs, total number of bites they had, circumstances of bite events, and complications and medical treatment of each bite. Bite risk was quantified by incidence, mean time to first bite, and a Cox proportional hazards model. Rates of complications and the medical burden of bites were compared between combat soldiers and noncombat dogkeepers. Bite locations were presented graphically. Seventy-eight soldiers participated and reported on 139 bites. Mean time of working with dogs was 16 months (standard deviation, ±9.4 months). Overall bite incidence was 11 bites per 100 person-months; the mean time to first bite event was 6.3 months. The Cox proportional hazards model showed that none of baseline characteristics significantly increased bite hazard. About 90% of bites occurred during routine activities, and 3.3% occurred on combat missions. Only in 9% of bite events did soldiers observed the safety precautions code. Bite complications included fractures, need for intravenous antibiotic treatment and surgical repair, prominent scarring, diminished sensation, and stiffness of proximal joints. Bite complications were similar between combat soldiers and dogkeepers. Most bites (57%) were located on hands and arms. MWD bites are an occupational hazard resulting in significant medical burden. Hands and arms were most common bite locations. Observance of safety precautions may be

Durability of two water repelents applied to granite

Directory of Open Access Journals (Sweden)

Rivas, T.

1998-06-01

Full Text Available The durability of two water-repellents for granitic stonework was determined. Weathered and sound samples of granites widely used in building construction and restoration in Galicia (NW Spain were treated with water repellents of known efficacy, and then subjected to two artificial weathering tests: prolonged exposure to UV light, and sodium sulphate crystallization cycles. In both tests, but especially in the salt crystallization cycles, both treatments rapidly lost their water-repellency. Furthermore, the hydrophobic layer of water repellent impeded salt mobility, favouring fissuration parallel to the treated surface, which was eventually shed in the form of a plaque.

Se presentan los resultados de la durabilidad de dos tratamientos de hidrofugación aplicados a rocas graníticas ampliamente utilizados en la construcción de edificios en Galicia (Noroeste de España. Tras la evaluación de la eficacia de dichos tratamientos, cuyos resultados se presentaron en un trabajo anterior, se someten las muestras tratadas a dos ensayos diferentes de envejecimiento acelerado: ciclos de exposición a la luz ultravioleta y ciclos de cristalización de sulfato de sodio. Los productos hidrofugantes muestran una escasa resistencia a ambos ensayos, sobre todo a los ciclos de cristalización de sulfato de sodio; esta débil durabilidad se manifiesta en una rápida pérdida de sus propiedades hidrofugantes. Así mismo, se observa que la presencia de la capa hidrófoba en la piedra funciona como una barrera frente a la movilidad de sales, lo que ocasiona el total desprendimiento de aquella y un fuerte deterioro del material rocoso.

Open bite treatment using clear aligners.

Science.gov (United States)

Guarneri, Maria Paola; Oliverio, Teresa; Silvestre, Ivana; Lombardo, Luca; Siciliani, Giuseppe

2013-09-01

A 35-year-old female patient with dentoalveolar open bite of 4 mm, molar Class I malocclusion, centered midlines, moderate crowding, and labial inclination of the lower incisor was treated with clear aligners to reduce protrusion and close the anterior open bite. The result showed that clear aligners were an effective method with which to correct this malocclusion. The treatment was complete after 18 months. The patient was satisfied with her new appearance and function.

Rat bite fever.

NARCIS (Netherlands)

Gaastra, W.; Boot, R.G.A.; Ho, H.; Lipman, L.J.A.

2009-01-01

Rat bite fever (RBF) is a bacterial zoonosis for which two causal bacterial species have been identified: Streptobacillis moniliformis and Spirillum minus. Haverhill fever (HF) is a form of S. moniliformis infection believed to develop after ingestion of contaminated food or water. Here the

Biologically inspired hairy surfaces for liquid repellency

Science.gov (United States)

Hsu, Shu-Hau

Owing to remarkable features, such as self-cleaning, anti-biofouling and drag reduction, interest on rendering surfaces water-repellent has significantly grown within this decade. Attempts on making surfaces "superhydrophobic", where high water contact angle (θc >150°) accompanied with only few degrees of roll-off angle, have been extensively demonstrated through the mimicking of the surface chemistry and morphology of lotus leaves. This appealing phenomenon also exists on another structure from nature: surfaces comprising soft hairs. Although the role of this piliferous integument has long been recognized for providing life, arthropods in particular, waterrepellency, the synthetic superhydrophobic surfaces based on this structure are still very limited. In this study, the goal was to develop a novel liquid-repellent surface by mimicking the hairy exterior of species. The artificial hairy surfaces were prepared by means of pressurized membrane casting, in which thermoplastic sheets were forced to flow into porous membranes at elevated temperature. The G-shaped pillars on the membrane cast polypropylene substrate are particularly similar to the conformation of natural hairs. The principle of this fabrication technique is relatively accessible and is expected to be compatible with large-area fabrication of superhydrophobic interfaces. The artificial hairy surface features perfectly hydrophobic response where no contact angle hysteresis was observed from video assessment. Thus the artificial hairy surface of the current work appears to be the first report to have such extreme hydrophobicity with only structural modification from the original substrate. This ultralow adhesion to water droplet is believed to be attributed to the hydrophobic methyl groups and the mechanical response of the artificial hairs. Liquid repellency of the hairy surfaces was further enhanced by coating with fluorocarbon (CF) layers via deep reactive ion etching (DRIE). The contact angle of

Dental image replacement on cone beam computed tomography with three-dimensional optical scanning of a dental cast, occlusal bite, or bite tray impression.

Science.gov (United States)

Kang, S-H; Lee, J-W; Lim, S-H; Kim, Y-H; Kim, M-K

2014-10-01

The goal of the present study was to compare the accuracy of dental image replacement on a cone beam computed tomography (CBCT) image using digital image data from three-dimensional (3D) optical scanning of a dental cast, occlusal bite, and bite tray impression. A Bracket Typodont dental model was used. CBCT of the dental model was performed and the data were converted to stereolithography (STL) format. Three experimental materials, a dental cast, occlusal bite, and bite tray impression, were optically scanned in 3D. STL files converted from the CBCT of the Typodont model and the 3D optical-scanned STL files of the study materials were image-registered. The error range of each methodology was measured and compared with a 3D optical scan of the Typodont. For the three materials, the smallest error observed was 0.099±0.114mm (mean error±standard deviation) for registering the 3D optical scan image of the dental cast onto the CBCT dental image. Although producing a dental cast can be laborious, the study results indicate that it is the preferred method. In addition, an occlusal bite is recommended when bite impression materials are used. Copyright © 2014 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Snake-bite-induced Acute Kidney Injury

International Nuclear Information System (INIS)

Naqvi, R.

2016-01-01

Objective: To describe the clinical spectrum and outcome of patients presenting to a tertiary care kidney center, developing acute kidney injury (AKI) after snake-bite. Study Design: An observational study. Place and Duration of Study: Nephrology Department, Sindh Institute of Urology and Transplantation (SIUT), Karachi, from January 1990 to December 2014. Methodology: All patients coming to SIUT identified as having AKI after snake-bite during the study period were included. AKI was defined according to RIFLE criteria with sudden rise in creatinine or decline in urine output or both. Demographics, clinical presentation, laboratory profile, and final outcome was noted. Result: During the studied period, 115 cases of AKI, secondary to snake-bite, were registered at this institution. Median age of patients was 35.92 ±15.04 (range: 6 - 70) years and male to female ratio was 1.6:1. Time from bite and referral to this hospital ranged from 2 to 28 days (mean: 8.77 ±5.58 days). Oligo-anuria was the most common presentation, being found in 98 (93.90 percentage) patients. Bleeding diathesis was reported in 75 (65.21 percentage) patients on presentation. All patients had normal sized, non-obstructed kidneys on ultrasonography, with no previous comorbids. Renal replacement therapy (RRT) was required in 106 (92.17 percentage) patients. Complete recovery was seen in 59 (51.30 percentage), while 15 (13.04 percentage) patients expired during acute phase of illness, 4 (3.47 percentage) developed CKD, 11 (9.56 percentage) required dialysis beyond 90 days, and 26 (22.60 percentage) were lost to long-term follow-up. Conclusion: Snake-bite, leading to multiple complications including renal failure and death, is a major health issue in tropical countries. Late referral of these patients to specialized centres Result in undesirable outcome. (author)

The management of dog bite injuries of genitalia in paediatric age

Directory of Open Access Journals (Sweden)

Mirko Bertozzi

2013-01-01

Full Text Available Dog bite injuries are common in children and represent an important health-care problem. Most dog bite injuries involve the face or an extremity. Victims tend to seek medical care quickly. Dog bites to the external genitalia are rarely reported, but they potentially result in morbidity if improperly managed. Morbidity is also directly related to the severity of initial wound. Guidelines for the management of dog bites include irrigation, dιbridment, antibiotic therapy, consideration of tetanus and rabies immunisation and suture of wounds or surgical reconstruction. Literature review was conducted and focused to analyze the management of dog bite lesions involving external genitalia.

Status and Prospect of Test Methods of Quality Silicone Water Repellent for Protecting Reinforced Concrete

Energy Technology Data Exchange (ETDEWEB)

Sun, H. Y.; Yuan, Z. Y.; Yang, Z.; Shan, G. L. [Nanjing Hydraulic Research Institute, Nanjing (China); Shen, M. X. [Hehai University, Nanjing (China)

2017-06-15

Impregnating with quality silicone water repellent on the concrete surface is an effective method of protecting concrete. Quality silicone water repellent has been widely used in the engineering profession because of its desirable properties such as hydrophobicity, keeping concrete breathable and preserving the original appearance of the concrete. The companies in China that produce silicone water repellent are listed. Test methods in the specifications or standards about silicone water repellent in China are summed. The test methods relative to durability of concrete impregnated with silicone water repellent (such as resistant to chloride ion penetration, resistant to alkali, resistance to freezing and thawing and weather ability etc.) and the constructive quality (such as water absorption rate, impregnating depth and the dry velocity coefficient etc.) are compared and analyzed. The results indicate that there are differences among test methods relative to different specifications with the same index and therefore, confusion has ensued when selecting test methods. All test methods with the exception of the method of water absorption rate by using a Karsten flask are not non-destructive methods or conducted in a laboratory. Finally, further research on silicone water repellent during application is proposed.

Status and Prospect of Test Methods of Quality Silicone Water Repellent for Protecting Reinforced Concrete

International Nuclear Information System (INIS)

Sun, H. Y.; Yuan, Z. Y.; Yang, Z.; Shan, G. L.; Shen, M. X.

2017-01-01

Impregnating with quality silicone water repellent on the concrete surface is an effective method of protecting concrete. Quality silicone water repellent has been widely used in the engineering profession because of its desirable properties such as hydrophobicity, keeping concrete breathable and preserving the original appearance of the concrete. The companies in China that produce silicone water repellent are listed. Test methods in the specifications or standards about silicone water repellent in China are summed. The test methods relative to durability of concrete impregnated with silicone water repellent (such as resistant to chloride ion penetration, resistant to alkali, resistance to freezing and thawing and weather ability etc.) and the constructive quality (such as water absorption rate, impregnating depth and the dry velocity coefficient etc.) are compared and analyzed. The results indicate that there are differences among test methods relative to different specifications with the same index and therefore, confusion has ensued when selecting test methods. All test methods with the exception of the method of water absorption rate by using a Karsten flask are not non-destructive methods or conducted in a laboratory. Finally, further research on silicone water repellent during application is proposed.

Higher glandular trichome density in tomato leaflets and repellence to spider mites Alta densidade de tricomas glandulares em tomateiro e aumento da repelência a ácaros rajados

Directory of Open Access Journals (Sweden)

Wilson Roberto Maluf

2007-09-01

Full Text Available The objective of this work was to evaluate the feasibility of selection for higher glandular trichome densities, as an indirect criterion of selection for increasing repellence to spider mites Tetranychus urticae, in tomato populations derived from an interspecific cross between Lycopersicon esculentum x L. hirsutum var. glabratum PI 134417. Trichome densities were evaluated in 19 genotypes, including 12 from advanced backcross populations, derived from the original cross L. esculentum x L. hirsutum var. glabratum PI 134417. Counts were made both on the adaxial and abaxial leaf surfaces, and trichomes were classified into glandular types IV and VI, other glandular types (types I+VII, and nonglandular types. Mite repellence was measured by distances walked by mites onto the tomato leaf surface after 20, 40 and 60 min. Spider mite repellence biotests indicated that higher densities of glandular trichomes (especially type VI decreased the distances walked by the mites onto the tomato leaf surface. Selection of plants with higher densities of glandular trichomes can be an efficient criterion to obtain tomato genotypes with higher resistance (repellence to spider mites.O objetivo deste trabalho foi avaliar a eficiência da seleção para maior densidade de tricomas glandulares na resistência (repelência ao ácaro Tetranychus urticae, em populações de tomate derivadas do cruzamento interespecífico Lycopersicon esculentum x L. hirsutum var. glabratum PI 134417. Foram avaliados 19 genótipos quanto à densidade de tricomas, que incluíram 12 derivados de populações avançadas de retrocruzamentos, obtidos a partir do cruzamento original L. esculentum x L. hirsutum var. glabratum PI 134417. Nas faces abaxial e adaxial dos folíolos, realizaram-se as contagens e os tricomas foram classificados em glandulares tipo IV e VI, outros glandulares (tipo I e VII e não glandulares. A repelência aos ácaros foi medida pela distância média, percorrida pelo

Appetite for self-destruction: suicidal biting as a nest defense strategy in Trigona stingless bees.

Science.gov (United States)

Shackleton, Kyle; Al Toufailia, Hasan; Balfour, Nicholas J; Nascimento, Fabio S; Alves, Denise A; Ratnieks, Francis L W

Self-sacrificial behavior represents an extreme and relatively uncommon form of altruism in worker insects. It can occur, however, when inclusive fitness benefits are high, such as when defending the nest. We studied nest defense behaviors in stingless bees, which live in eusocial colonies subject to predation. We introduced a target flag to nest entrances to elicit defensive responses and quantified four measures of defensivity in 12 stingless bee species in São Paulo State, Brazil. These included three Trigona species, which are locally known for their aggression. Species varied significantly in their attack probability (cross species range = 0-1, P  bees (3.5-508.7 s, P  bee. Our results indicate that suicidal biting may be a widespread defense strategy in stingless bees, but it is not universal.

The management of animal bites in the United kingdom.

Science.gov (United States)

Evgeniou, E; Markeson, D; Iyer, S; Armstrong, A

2013-01-01

Animal bites represent a significant global health issue. The evidence in the literature regarding their management in many areas is conflicting and unclear. This project attempts to identify current evidence in the literature on the management of animal bites and assess if current practice in the United Kingdom is evidence based. A literature review on the management of animal bites was performed, and a national UK survey was contacted using a questionnaire based on the available evidence in the literature. The results from this survey show that 98% of plastic surgery units routinely use prophylactic antibiotics in all animal bite wounds; 58% close low-risk injuries primarily after initial washout, and there are conflicting opinions regarding the management of associated fractures and soft tissue injuries. The available data in the literature suggest that appropriate wound management is the most important factor for prevention of infection in animal bites. Antibiotic prophylaxis should only be given in high-risk wounds and primary closure should be performed in low-risk wounds. The management protocols of many plastic surgery units often diverge from the available evidence within the literature. On the basis of a thorough literature review, a guideline for the management of animal bites is presented. Future studies should investigate the management of associated fractures and soft tissue injuries.

Bioassay-guided investigation of two Monarda essential oils as repellents of yellow fever mosquito Aedes aegypti.

Science.gov (United States)

Tabanca, Nurhayat; Bernier, Ulrich R; Ali, Abbas; Wang, Mei; Demirci, Betul; Blythe, Eugene K; Khan, Shabana I; Baser, K Husnu Can; Khan, Ikhlas A

2013-09-11

As part of an ongoing research program to identify active mosquito repellents, Monarda bradburiana Beck and Monarda fistulosa L. essential oils showed good repellent activity with minimum effective dosages (MED) of 0.055 ± 0.036 and 0.078 ± 0.027 mg/cm(2), respectively, compared to reference standard N,N-diethyl-3-methylbenzamide (DEET) (0.039 ± 0.014 mg/cm(2)). Systematic bioassay-guided fractionation of essential oils of both Monarda species was performed to identify the active repellent compounds, and isolated pure compounds were individually tested for repellency. Of the isolated compounds, carvacrol, thymol, eugenol, and carvacrol methyl ether were found to be the repellent compounds with MEDs in the range of 0.013-0.063 mg/cm(2). Active repellent compounds were also tested for larvicidal activity against 1-day-old Aedes aegypti larvae. Thymol was the best larvicide among the tested individual compounds (LD50 of 13.9 ppm). None of the individual compounds showed cytotoxicity against mammalian cells; however, the essential oils were toxic to all cell lines.

Higher glandular trichome density in tomato leaflets and repellence to spider mites

International Nuclear Information System (INIS)

Maluf, Wilson Roberto; Inoue, Irene Fumi; Ferreira, Raphael de Paula Duarte; Gomes, Luiz Antonio Augusto; Castro, Evaristo Mauro de; Cardoso, Maria das Gracas

2007-01-01

The objective of this work was to evaluate the feasibility of selection for higher glandular trichome densities, as an indirect criterion of selection for increasing repellence to spider mites Tetranychus urticae, in tomato populations derived from an interspecific cross between Lycopersicon esculentum x L. hirsutum var. glabratum PI 134417. Trichome densities were evaluated in 19 genotypes, including 12 from advanced backcross populations, derived from the original cross L. esculentum x L. hirsutum var. glabratum PI 134417. Counts were made both on the adaxial and abaxial leaf surfaces, and trichomes were classified into glandular types IV and VI, other glandular types (types I+VII), and nonglandular types. Mite repellence was measured by distances walked by mites onto the tomato leaf surface after 20, 40 and 60 min. Spider mite repellence biotests indicated that higher densities of glandular trichomes (especially type VI) decreased the distances walked by the mites onto the tomato leaf surface. Selection of plants with higher densities of glandular trichomes can be an efficient criterion to obtain tomato genotypes with higher resistance (repellence) to spider mites. (author)

Shortcomings in snake bite management in rural Cameroon: a case report.

Science.gov (United States)

Tianyi, Frank-Leonel; Dimala, Christian Akem; Feteh, Vitalis Fambombi

2017-06-08

Snake bites are an important public health problem in developing countries with most bites occurring in rural areas. Severe envenomation often occurs in children and following bites to the face. Prompt administration of potent anti-venom remains the mainstay of management. However in Cameroon, the use of anti-venoms is limited by non-availability, high cost (where available) and poor mastery of treatment guidelines. We present a 10-year-old muslim Cameroonian child from an enclaved rural area, brought to the hospital 12 h after a snake bite to the face, with signs of severe envenomation. Despite the suboptimal anti-venom dose administered to this patient due to a stock out of this medication, supportive therapy was beneficial in ensuring a positive outcome and satisfactory recovery. This highlights snake bites as a public health problem due to the lack of snake anti-venoms in peripheral health facilities, rendering them unable to appropriately manage these cases. National health policies should encourage constant peripheral availability of anti-venoms and the institution of an intervention package for snake bite management, comprising: treatment protocol, staff training, monitoring of compliance and community education to help reduce the mortality and morbidity from snake bites.

Deep bite malocclusion: exploration of the skeletal and dental factors

International Nuclear Information System (INIS)

Bhateja, N.K.; Fida, M.; Shaikh, A.

2016-01-01

Correction of deep bite is crucial for maintenance of dental hard and soft tissue structures and for prevention of temporomandibular joint disorders. Exploration of underlying skeletal and dental factors is essential for efficient and individualized treatment planning. To date etiological factors of dental and skeletal deep bite have not been explored in Pakistani orthodontic patients. The objectives of this study were to explore frequencies of dental and skeletal etiological factors in deep bite patients and to determine correlations amongst dental and skeletal etiological factors of deep bite. Methods: The study included a total of 113 subjects (males=35; females=78) with no craniofacial syndromes or prior orthodontic treatment. Pre-treatment orthodontic records were used to evaluate various dental and skeletal parameters. Descriptive statistics of each parameter were calculated. The various study parameters were correlated using Pearson's Correlation. Results: Deep curve of Spee was most frequently seen factor of dental deep bite (72.6%), followed by increased coronal length of upper incisors (28.3%), retroclined upper incisors (17.7%), retroclined lower incisors (8%) and increased coronal length of lower incisors (5.3%). Decreased gonial angle was most commonly found factor of skeletal deep bite (43.4%), followed by decreased mandibular plane angle (27.4%) and maxillary plane's clockwise rotation (26.5%). Frankfort mandibular plane angle and gonial angle showed a strong positive correlation (r=0.66, p=0.000). Conclusions: Reduced gonial angle is most frequently seen skeletal factor, signifying the importance of angulation and growth of ramus in development of deep bite. Deep curve of Spee is most frequently seen dental etiological component in deep bite subjects, hence signifying the importance of intruding the lower anterior teeth. (author)

Rat bite fever without fever.

Science.gov (United States)

Stehle, P; Dubuis, O; So, A; Dudler, J

2003-09-01

Rat bite fever is a rarely reported acute febrile bacterial illness caused by Streptobacillus moniliformis or Spirillum minus following a rat bite. It is classically characterised by abrupt onset of fever with rigors, myalgias, headache, and the appearance of a generalised maculopapular petechial skin rash. Polyarthritis complicates the course of the disease in up to 50% of infected patients, and numerous hurdles can make the diagnosis particularly difficult in the absence of fever or rash, as in the present case. A high degree of awareness is necessary to make the correct diagnosis in such cases. Diagnosis has important prognostic implications as the disease is potentially lethal, but easily treatable.

Improvement of Water Movement in an Undulating Sandy Soil Prone to Water Repellency

NARCIS (Netherlands)

Oostindie, K.; Dekker, L.W.; Wesseling, J.G.; Ritsema, C.J.

2011-01-01

The temporal dynamics of water repellency in soils strongly influence water flow. We investigated the variability of soil water content in a slight slope on a sandy fairway exhibiting water-repellent behavior. A time domain reflectometry (TDR) array of 60 probes measured water contents at 3-h

Early orthodontic treatment of skeletal open-bite malocclusion with the open-bite bionator: a cephalometric study.

Science.gov (United States)

Defraia, Efisio; Marinelli, Andrea; Baroni, Giulia; Franchi, Lorenzo; Baccetti, Tiziano

2007-11-01

This study was designed to evaluate the effectiveness of the open-bite bionator in growing subjects with increased vertical dimensions. The records of 20 subjects with high-angle skeletal relationships (MPA > or =25 degrees) were examined. Cephalometric measurements were compared with those obtained from 23 sets of records of an untreated group matched according to age, sex, vertical skeletal relationships, and time intervals between records. Lateral cephalograms were analyzed before the start of treatment (mean age; 8.3 years) and after therapy and retention, with a mean period of observation of 2.5 years. The treated group had a significantly smaller palatal plane-mandibular plane angle (-1.9 degrees) and a greater overbite (+1.5 mm) associated with a significantly smaller overjet when compared with the control group. Based on the analysis of this sample, early treatment of skeletal open bite with the open-bite bionator appears to produce a modest effect that mainly consists of significant improvement in intermaxillary divergence. No favorable effects on the extrusion of posterior teeth were found.

Wetting properties of fungi mycelium alter soil infiltration and soil water repellency in a γ-sterilized wettable and repellent soil.

Science.gov (United States)

Chau, Henry Wai; Goh, Yit Kheng; Vujanovic, Vladimir; Si, Bing Cheng

2012-12-01

Soil water repellency (SWR) has a drastic impact on soil quality resulting in reduced infiltration, increased runoff, increased leaching, reduced plant growth, and increased soil erosion. One of the causes of SWR is hydrophobic fungal structures and exudates that change the soil-water relationship. The objective of this study was to determine whether SWR and infiltration could be manipulated through inoculation with fungi. The effect of fungi on SWR was investigated through inoculation of three fungal strains (hydrophilic -Fusarium proliferatum, chrono-amphiphilic -Trichoderma harzianum, and hydrophobic -Alternaria sp.) on a water repellent soil (WR-soil) and a wettable soil (W-soil). The change in SWR and infiltration was assessed by the water repellency index and cumulative infiltration respectively. F. proliferatum decreased the SWR on WR-soil and slightly increased SWR in W-soil, while Alternaria sp. increased SWR in both the W-soil and the WR-soil. Conversely T. harzianum increased the SWR in the W-soil and decreased the SWR in the WR-soil. All strains showed a decrease in infiltration in W-soil, while only the F. proliferatum and T. harzianum strain showed improvement in infiltration in the WR-soil. The ability of fungi to alter the SWR and enmesh soil particles results in changes to the infiltration dynamics in soil. Copyright © 2012 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

Bug bites and stings: When to see a dermatologist

Medline Plus

Full Text Available ... bites Although most bug bites are harmless, some can spread dangerous diseases like Zika virus, dengue, Lyme ... and tuck your shirt into your pants. You can also pre-treat outer layers of clothing with ...

Bug bites and stings: When to see a dermatologist

Medline Plus

Full Text Available ... var c = 0; c Tips to prevent and treat bug bites Although most bug bites are harmless, some can spread dangerous diseases like Zika virus, dengue, Lyme disease, and malaria. Particularly if you’re ...

Bug bites and stings: When to see a dermatologist

Medline Plus

Full Text Available ... a dermatologist Why see a board-certified dermatologist? Home Public and patients Skin, hair, and nail care ... bites and stings can be safely treated at home. To treat bug bites and stings at home, ...

Possible transmission of HIV Infection due to human bite

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Bandivdekar Atmaram H

2011-03-01

Full Text Available Abstract The potential risk of HIV-1 infection following human bite although epidemiologically insignificant, but it is biologically possible. There are anecdotal reports of HIV transmission by human bites particularly if saliva is mixed with blood. The oral tissues support HIV replication and may serve as a previously unrecognized HIV reservoir. The HIV infected individuals have more viruses in blood than saliva, possibly due to the potent HIV-inhibitory properties of saliva. The case presented here is of a primary HIV infections following a human bite where in the saliva was not blood stained but it got smeared on a raw nail bed of a recipient. The blood and saliva of the source and blood of the recipient showed a detectable viral load with 91% sequence homology of C2-V3 region of HIV gp120 between the two individuals. The recipient did not receive PEP [post exposure prophylaxis] as his family physician was unaware of salivary transmission. The family physician should have taken PEP decision after proper evaluation of the severe and bleeding bite. Hence it is necessary to treat the HIV infected human bites with post exposure prophylaxis.

New procedure for sampling infiltration to assess post-fire soil water repellency

Science.gov (United States)

P. R. Robichaud; S. A. Lewis; L. E. Ashmun

2008-01-01

The Mini-disk Infiltrometer has been adapted for use as a field test of post-fire infiltration and soil water repellency. Although the Water Drop Penetration Time (WDPT) test is the common field test for soil water repellency, the Mini-disk Infiltrometer (MDI) test takes less time, is less subjective, and provides a relative infiltration rate. For each test, the porous...

The management of dog bite injuries of genitalia in paediatric age ...

African Journals Online (AJOL)

Dog bite injuries are common in children and represent an important health-care problem. Most dog bite injuries involve the face or an extremity. Victims tend to seek medical care quickly. Dog bites to the external genitalia are rarely reported, but they potentially result in morbidity if improperly managed. Morbidity is also ...

A retrospective review of snake bite victims admitted in a tertiary ...

African Journals Online (AJOL)

Objective: Snake bite remains major public health problem worldwide. We present our experience with cases of snake bites managed in our tertiary care teaching center of South India. Materials and Methods: The details of all patients with snake bite admitted to a tertiary teaching care hospital from 2010 to 2012 were ...

Bio-inspired water repellent surfaces produced by ultrafast laser structuring of silicon

International Nuclear Information System (INIS)

Barberoglou, M.; Zorba, V.; Stratakis, E.; Spanakis, E.; Tzanetakis, P.; Anastasiadis, S.H.; Fotakis, C.

2009-01-01

We report here an efficient method for preparing stable superhydrophobic and highly water repellent surfaces by irradiating silicon wafers with femtosecond laser pulses and subsequently coating them with chloroalkylsilane monolayers. By varying the laser pulse fluence on the surface one can successfully control its wetting properties via a systematic and reproducible variation of roughness at micro- and nano-scale, which mimics the topology of natural superhydrophobic surfaces. The self-cleaning and water repellent properties of these artificial surfaces are investigated. It is found that the processed surfaces are among the most water repellent surfaces ever reported. These results may pave the way for the implementation of laser surface microstructuring techniques for the fabrication of superhydrophobic and self-cleaning surfaces in different kinds of materials as well

Clinical categories of exaggerated skin reactions to mosquito bites and their pathophysiology.

Science.gov (United States)

Tatsuno, Kazuki; Fujiyama, Toshiharu; Matsuoka, Hiroyuki; Shimauchi, Takatoshi; Ito, Taisuke; Tokura, Yoshiki

2016-06-01

Mosquito bites are skin irritating reactions, which usually resolve spontaneously without intensive medical care. However, in certain situations, mosquito bites may form a more vicious reaction, sometimes accompanying fever and systemic symptoms. In such cases, the presence of rare hematological disorders, abnormalities in eosinophils and/or association with Epstein-Barr virus (EBV) may underlie. Importantly, hypersensitivity to mosquito bites (HMB), which is characterized by necrotic skin reactions to mosquito bites with various systemic symptoms, is often observed in association with EBV infection and natural killer (NK) cell lymphoproliferative disorder. Exaggerated skin reaction to mosquito bites is also seen in Wells' syndrome. While strong Th2-skewing immune dysregulation is apparent in the patients, they also show robust CD4(+) T cell proliferation in response to mosquito salivary gland extracts, indicating close association between Wells' syndrome and mosquito bites. Similar skin reaction to mosquito bites is also noticed in certain types of B cell neoplasm, although the role of B cells in this peculiar reaction to mosquito bites is yet to be elucidated. In this review, we will discuss the current knowledge of exaggerated reaction toward mosquito bites seen in conjunction with these unique hematological disorders, and examine the scientific studies and observations reported in previous literatures to organize our current understanding of the pathogenesis of this distinct disorder. Copyright © 2016 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

Water repellency, plants, agriculture abandonment and fire in citrus plantations. The Canyoles river watershed study site

Science.gov (United States)

Cerdà, Artemi; Jordán, Antonio; Doerr, Stefan Helmut

2017-04-01

Soil water repellency (SWR) is a key soil property that determine the soil and water losses, soil fertility and plant development. Although until the 90's the soil water repellency was seeing as an uncommon soil characteristic, now is considered a key soil property to understand the soil hydrology (Alanís et al., 2016; Hewelke et al., 2016; Keesstra et al., 2016; Jiménez-Morillo et al., 2016). The inspiring research of Leonard DeBano and Stefan H Doerr changed the fate of the science (DeBano, 2000; Doerr et al. 2000). Soil water repellency was associated to forest fire affected land due to the pioneer contribution of professor DeBano in the 70's and Professor Doerr in the 90's. The research during the last two decades demonstrate that fire affects the reallocation of the hydrophobic substances and can reduce or increase the severity of the soil water repellence at different soil depths and horizons. The SWR is usually measured by sampling to show the influence of key soil properties (texture, structure, plant cover, litter, season…) on the degree of soil water repellency. The sampling is applied usually with a few drops when the Water Drop Penetration Time method is applied, and this inform of the time of penetration, but few researches focussed in the spatial distribution of the water repellency, which is a key factor of the runoff generation, the water infiltration and the water redistribution such as demonstrate the wetting fronts. Our approach research the spatial distribution of the water repellency by means of an intense sampling of soil surface water repellency. One thousand drops were distributed in a square meter (100 lines separated 1 cm and 100 drops per each line of 100 cm, with a total od 1000 drops in 1m2) on 10 sampling points on 4 land managements: ploughing and herbicide agriculture fields treatment), abandoned 10 years, and burnt. The research was carried out in citrus plantations of the Canyoles river watershed. The results show that the

Microbial analysis of bite marks by sequence comparison of streptococcal DNA.

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Darnell M Kennedy

Full Text Available Bite mark injuries often feature in violent crimes. Conventional morphometric methods for the forensic analysis of bite marks involve elements of subjective interpretation that threaten the credibility of this field. Human DNA recovered from bite marks has the highest evidentiary value, however recovery can be compromised by salivary components. This study assessed the feasibility of matching bacterial DNA sequences amplified from experimental bite marks to those obtained from the teeth responsible, with the aim of evaluating the capability of three genomic regions of streptococcal DNA to discriminate between participant samples. Bite mark and teeth swabs were collected from 16 participants. Bacterial DNA was extracted to provide the template for PCR primers specific for streptococcal 16S ribosomal RNA (16S rRNA gene, 16S-23S intergenic spacer (ITS and RNA polymerase beta subunit (rpoB. High throughput sequencing (GS FLX 454, followed by stringent quality filtering, generated reads from bite marks for comparison to those generated from teeth samples. For all three regions, the greatest overlaps of identical reads were between bite mark samples and the corresponding teeth samples. The average proportions of reads identical between bite mark and corresponding teeth samples were 0.31, 0.41 and 0.31, and for non-corresponding samples were 0.11, 0.20 and 0.016, for 16S rRNA, ITS and rpoB, respectively. The probabilities of correctly distinguishing matching and non-matching teeth samples were 0.92 for ITS, 0.99 for 16S rRNA and 1.0 for rpoB. These findings strongly support the tenet that bacterial DNA amplified from bite marks and teeth can provide corroborating information in the identification of assailants.

Spatial repellency of metofluthrin-impregnated multilayer paper strip against Aedes albopictus under outdoor conditions, Nagasaki, Japan

OpenAIRE

Argueta, Tamara Belzabel Obispo; Kawada, Hitoshi; Takagi, Masahiro

2004-01-01

Spatial repellency of a new device in which metofluthrin, a newly synthesized pyrethroid, is impregnated into a multilayer paper strip, against Aedes albopictus was evaluated under outdoor conditions. High spatial repellency (>80%) with the metofluthrin-impregnated (200 mg) device lasted for more than 6 weeks, while the repellency with the same device impregnated with the same amount of transfluthrin declined within 5 weeks after treatment.

Geographic variation in access to dog-bite care in Pakistan and risk of dog-bite exposure in Karachi: prospective surveillance using a low-cost mobile phone system.

Directory of Open Access Journals (Sweden)

Syed Mohammad Asad Zaidi

Full Text Available BACKGROUND: Dog-bites and rabies are under-reported in developing countries such as Pakistan and there is a poor understanding of the disease burden. We prospectively collected data utilizing mobile phones for dog-bite and rabies surveillance across nine emergency rooms (ER in Pakistan, recording patient health-seeking behaviors, access to care and analyzed spatial distribution of cases from Karachi. METHODOLOGY AND PRINCIPAL FINDINGS: A total of 6212 dog-bite cases were identified over two years starting in February 2009 with largest number reported from Karachi (59.7%, followed by Peshawar (13.1% and Hyderabad (11.4%. Severity of dog-bites was assessed using the WHO classification. Forty percent of patients had Category I (least severe bites, 28.1% had Category II bites and 31.9% had Category III (most severe bites. Patients visiting a large public hospital ER in Karachi were least likely to seek immediate healthcare at non-medical facilities (Odds Ratio = 0.20, 95% CI 0.17-0.23, p-value<0.01, and had shorter mean travel time to emergency rooms, adjusted for age and gender (32.78 min, 95% CI 31.82-33.78, p-value<0.01 than patients visiting hospitals in smaller cities. Spatial analysis of dog-bites in Karachi suggested clustering of cases (Moran's I = 0.02, p value<0.01, and increased risk of exposure in particular around Korangi and Malir that are adjacent to the city's largest abattoir in Landhi. The direct cost of operating the mHealth surveillance system was USD 7.15 per dog-bite case reported, or approximately USD 44,408 over two years. CONCLUSIONS: Our findings suggest significant differences in access to care and health-seeking behaviors in Pakistan following dog-bites. The distribution of cases in Karachi was suggestive of clustering of cases that could guide targeted disease-control efforts in the city. Mobile phone technologies for health (mHealth allowed for the operation of a national-level disease reporting and surveillance system

Biting rates and developmental substrates for biting midges (Diptera: Ceratopogonidae) in Iquitos, Peru.

Science.gov (United States)

Mercer, David R; Spinelli, Gustavo R; Watts, Douglas M; Tesh, Robert B

2003-11-01

Biting midges (Diptera: Ceratopogonidae) were collected at 16 periurban and rural sites around Iquitos, Peru, between 17 October 1996 and 26 May 1997. Culicoides paraensis (Goeldi), the principal vector of Oropouche virus, was the most commonly collected species (9,086 flies) with Culicoides insinuatus Wirth & Blanton second (7,229 flies). Although both species were collected at all sampling sites (linear (distance surveyed approximately 25 km), C. paraensis dominated at northern collection sites (> 90%), whereas C. insinuatus prevailed at southern collection sites (> 60%). C. paraensis were collected from human sentinels at a constant rate throughout daylight hours, at similar rates during wet and dry months, and regardless of rainfall. Larval developmental substrates for C. paraensis included decaying platano (Musa x paradisiaca L. [Musaceae]) stems, stumps, flowers, fruits, and debris beneath platano trees as well as from soil beneath a fruiting mamay (Syzygium malaccense Merr. & Perry [Myrtaceae] ) tree and organic-rich mud along a lake shoreline. C. insinuatus adults likewise emerged from decaying platano and organic-rich mud along a lake shoreline, but also from debris accumulated in the axils of aguaje (Mauritia flexuosa L. [Palmae]) fronds and decaying citrus fruit. Despite high numbers of biting adults near putative substrates, adults of neither species emerged from other decomposing plant material, soil, phytotelmata, or artificial containers. Because both species of biting midges emerged in high numbers from all parts of platano (ubiquitous in Iquitos), it will be challenging to control them through sanitation.

Identification of repellent odorants to the body louse, Pediculus humanus corporis, in clove essential oil.

Science.gov (United States)

Iwamatsu, Takuma; Miyamoto, Daisuke; Mitsuno, Hidefumi; Yoshioka, Yoshiaki; Fujii, Takeshi; Sakurai, Takeshi; Ishikawa, Yukio; Kanzaki, Ryohei

2016-04-01

The control of body lice is an important issue for human health and welfare because lice act as vectors of disease such as typhus, relapsing fever, and trench fever. Body lice exhibit avoidance behavior to some essential oils, including clove essential oil. Therefore, odorants containing clove essential oil components may potentially be useful in the development of repellents to body lice. However, such odorants that induce avoidance behavior in body lice have not yet been identified from clove essential oil. Here, we established an analysis method to evaluate the avoidance behavior of body lice to specific odorants. The behavioral analysis of the body lice in response to clove essential oil and its constituents revealed that eugenol, a major component of clove essential oil, has strong repellent effect on body lice, whereas the other components failed to induce obvious avoidance behavior. A comparison of the repellent effects of eugenol with those of other structurally related odorants revealed possible moieties that are important for the avoidance effects to body lice. The repellent effect of eugenol to body lice was enhanced by combining it with the other major component of clove essential oil, β-caryophyllene. We conclude that a synthetic blend of eugenol and β-caryophyllene is the most effective repellent to body lice. This finding will be valuable as the potential use of eugenol as body lice repellent.

Spatial repellents on strips of camouflage netting reduce mosquito collections in a field environment

Science.gov (United States)

Barrier treatments can be effective in reducing host seeking mosquito vectors and provide an additional layer of passive defense, reducing disease risk. Devices designed to release spatial repellents or direct application of spatial repellents to artificial surfaces can serve as efficient barriers r...

Field Evaluations of Topical Arthropod Repellents in North, Central, and South America

Science.gov (United States)

2014-09-01

De La Rocque et al. 2011) and their spread into higher elevations of Africa, Latin America , and Asia (Epstein 2001). Dengue fever and...denguehemorrhagic fever have resurgeddramatically in Latin America (Zell 2004). In North America ,West Nile virus has impacted signiÞcantly the health and welfare of...VECTOR CONTROL, PEST MANAGEMENT, RESISTANCE, REPELLENTS Field Evaluations of Topical Arthropod Repellents in North, Central , and South America KENDRA

EFFECTS OF ESSENTIAL OIL FORMULATIONS ON THE ADULT INSECT TRIBOLIUM CASTANEUM (HERBST (COL., TENEBRIONIDAE

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Aleksandra Popovic

2013-06-01

Full Text Available Stored product pests such as Tribolium castaneum ( Herbst, 1979 are a major problem. Adult insects were obtained from laboratory cultures maintained in the dark in incubators at 25 1C and 70 80percent r.h., reared on wheat flour and fed with flour disks containing a known concentration of essential oil of 9 plants. The chemical components of essential oil of 3 plants, collected on the area of Montenegro, were also identified using GC-MS analysis. The results of insecticidal effect of essential oils were discussed. Also, mortality rate of adult insects was tested. In this research, the essential oils of C. glandulosa which were rich in monoterpene alcohols carvacrol and contained ketonic component showed strong insecticidal and fumigant activity against adults of T. castaneum. Less toxic effect showed essential oils of Satureja montana which had a lower carvacrol and ketonic content. On the other hand, essential oils of Teucrium polium which did not contain ketonic component did not show any activity. Therefore, it was observed that essential oils of C. glandulosa with concentration of 1.14% showed powerful toxic and repellent effect, with very high mortality rate after 24h (56,67%.

Effects of wildfire on soil water repellency in pine and eucalypt forest in central Portugal

Science.gov (United States)

Faria, Sílvia; Eufemia Varela, María.; Keizer, Jan Jacob

2010-05-01

Soil water repellency is a naturally occurring phenomenon that can be intensified by soil heating during fires. Fire-induced or -enhanced water repellency, together with the loss of plant cover, is widely regarded as a key factor in increased surface runoff and accelerated erosion in recently burnt areas. The present study is part of the EROSFIRE-II project, whose main aim is to assess and predict post-wildfire hydrological and erosion processes at multiple spatial scales, ranging from micro-plot (Pinus pinaster and Eucaliptus globulus). In addition, two similar but long unburned slopes were selected in the immediate surroundings. For a period of 10 months, starting November 2008, water repellency and moisture content of the 0-5 cm topsoil layer were measured in the field at monthly intervals. Repellency was measured using the ‘Molarity of an Ethanol Droplet' (MED) test, soil moisture content using a DECAGON EC5 sensor. The results revealed a very strong repellency (ethanol classes 6-7) at all four sites during the first sampling period in November 2008, suggesting that the immediate wildfire effects were minor for both forest types. In the subsequent 5 to 6 months, however, there was a definite tendency for higher ethanol classes at the recently burnt than the adjacent unburned sites. Especially in the case of the pine stands, this tendency was inverted during the remaining months. The above-mentioned differences between the neighboring sites reflected more pronounced temporal patters in the case of the unburned sites, where median repellency levels corresponded none to slight severity ratings from December to March (pine) or April (eucalypt). Such seasonal drops in repellency were considerably shorter at the two burnt sites (1-2 months) and also less pronounced, without median ethanol classes becoming zero as occurred at the burnt sites. The seasonal repellency patterns at the unburned sites could be explained rather well by changes in soil moisture content

Bullous reactions to bed bug bites reflect cutaneous vasculitis

Science.gov (United States)

This study evaluates bullous cutaneous reactions and sequential histopathology in an individual sensitized to bed bug bites in an effort to better understand the allergic response and histology associated with these bites. There was a progression of the inflammatory response across time ranging from...

Individual piglets' contribution to the development of tail biting

NARCIS (Netherlands)

Zonderland, J.J.; Kemp, B.; Bracke, M.B.M.; Hartog, den L.A.; Spoolder, H.A.M.

2011-01-01

Conflicting hypotheses exist about the contribution of individual pigs to the development of a tail-biting outbreak, but there is limited quantitative information to support or dismiss them. This study aims to quantify the development of tail-biting behaviour at pen and individual piglet level,

Management of common animal bites in the emergency centre

African Journals Online (AJOL)

Professor Engelbrecht's current fields of interest are bites, stings and poisonous plants. Correspondence to: ... Cross War Memorial Children's Hospital in. Cape Town ... infections. Wound infection with Pasteurella multocida usually occurs early (within 12 ..... Dog bite prevention: an assessment of child knowledge. J Pediatr ...

Temporal fluctuations in soil water repellency following wildfire in chaparral steeplands, southern California

Science.gov (United States)

K.R. Hubbert; V. Oriol

2005-01-01

Soil water repellency is partularly common in unburned chaparral, and its degree and duration can be influenced by seasonal weather conditions. Water repellency tends to increase in dry soils, whil eit decreases or vanishes following precipitation or extended periods of soil moisture. The 15426 ha Williams Fire provided an opportunity to investigate post-fire...

Mosquito Bites are Bad!

Centers for Disease Control (CDC) Podcasts

2016-08-11

In this podcast for kids, the Kidtastics talk about the dangers of mosquito bites and how to prevent getting them.  Created: 8/11/2016 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 8/11/2016.

Fumigant and repellent activities of essential oil extracted from Artemisia dubia and its main compounds against two stored product pests.

Science.gov (United States)

Liang, Jun-Yu; Guo, Shan-Shan; Zhang, Wen-Juan; Geng, Zhu-Feng; Deng, Zhi-Wei; Du, Shu-Shan; Zhang, Ji

2018-05-01

The major chemical constituents of the essential oil extracted from Artemisia dubia wall. ex Bess. (Family: Asteraceae) were found as terpinolene (19.02%), limonene (17.40%), 2,5-etheno[4.2.2]propella-3,7,9-triene (11.29%), isoelemicin (11.05%) and p-cymene-8-ol (5.93%). Terpinolene and limonene were separated as main components from the essential oil. The essential oil showed fumigant toxicity against Tribolium castaneum and Liposcelis bostrychophila with LC 50 values of 49.54 and 0.74 mg/L, respectively. The essential oil and isolated compounds of A. dubia showed repellency activities against both insects. Terpinolene and limonene showed the fumigant toxicity against T. castaneum. Terpinolene showed obvious fumigant toxicity against L. bostrychophila. The results indicated that the essential oil of A. dubia had potential to be developed into natural insecticides for controlling stored product pests.

Synergistic mosquito-repellent activity of Curcuma longa, Pogostemon heyneanus and Zanthoxylum limonella essential oils.

Science.gov (United States)

Das, N G; Dhiman, Sunil; Talukdar, P K; Rabha, Bipul; Goswami, Diganta; Veer, Vijay

2015-01-01

Mosquito repellents play an important role in preventing man-mosquito contact. In the present study, we evaluated the synergistic mosquito-repellent activity of Curcuma longa, Pogostemon heyneanus and Zanthoxylum limonella essential oils. The mosquito repellent efficacies of three essential oils were evaluated separately and in combination under laboratory and field conditions. N,N-Diethylphenylacetamide (DEPA) and dimethylphthalate (DMP) were used for comparison of the protection time of the mixture of essential oils. At an optimum concentration of 20%, the essential oils of C. longa, Z. limonella and P. heyneanus provided complete protection times (CPTs) of 96.2, 91.4 and 123.4 min, respectively, against Aedes albopictus mosquitoes in the laboratory. The 1:1:2 mixture of the essential oils provided 329.4 and 391.0 min of CPT in the laboratory and field trials, respectively. The percent increases in CPTs for the essential oil mixture were 30 for DMP and 55 for N,N-diethylphenylacetamide (DEPA). The synergistic repellent activity of the essential oils used in the present study might be useful for developing safer alternatives to synthetic repellents for personal protection against mosquitoes. Copyright © 2015 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

A new bite block for panoramic radiographs of anterior edentulous patients: A technical report.

Science.gov (United States)

Park, Jong-Woong; Symkhampha, Khanthaly; Huh, Kyung-Hoe; Yi, Won-Jin; Heo, Min-Suk; Lee, Sam-Sun; Choi, Soon-Chul

2015-06-01

Panoramic radiographs taken using conventional chin-support devices have often presented problems with positioning accuracy and reproducibility. The aim of this report was to propose a new bite block for panoramic radiographs of anterior edentulous patients that better addresses these two issues. A new panoramic radiography bite block similar to the bite block for dentulous patients was developed to enable proper positioning stability for edentulous patients. The new bite block was designed and implemented in light of previous studies. The height of the new bite block was 18 mm and to compensate for the horizontal edentulous space, its horizontal width was 7 mm. The panoramic radiographs using the new bite block were compared with those using the conventional chin-support device. Panoramic radiographs taken with the new bite block showed better stability and bilateral symmetry than those taken with the conventional chin-support device. Patients also showed less movement and more stable positioning during panoramic radiography with the new bite block. Conventional errors in panoramic radiographs of edentulous patients could be caused by unreliability of the chin-support device. The newly proposed bite block for panoramic radiographs of edentulous patients showed better reliability. Further study is required to evaluate the image quality and reproducibility of images with the new bite block.

Hypersensitivity to mosquito bite manifested as Skeeter syndrome

Directory of Open Access Journals (Sweden)

Rafael Pérez-Vanzzini

2015-02-01

Full Text Available The reactions to mosquito bites are immunological reactions with involvement of IgE, IgG and T cells mediated hypersensitivity. These reactions are common and range from small local reactions, large local reactions to systemic allergic reactions. Skeeter syndrome is defined as a large local induced inflammatory reaction to mosquito bite and sometimes accompanied by systemic symptoms such as fever and vomiting. Diagnosis is based on clinical history and physical examination, supported by the identification of specific IgE by skin testing. Treatment includes prevention, antihistamines and steroids in some cases. Specific immunotherapy still requires further study. This paper reports two cases of patients with hypersensitivity reactions to mosquito bites, which were evaluated in our center presenting positive skin tests.

Morphology of open bite.

Science.gov (United States)

Krey, Karl-Friedrich; Dannhauer, Karl-Heinz; Hierl, Thomas

2015-05-01

The purpose of this work was to define and illustrate the skeletal morphology of open-bite patients against the background of sagittal jaw relationships on the basis of lateral cephalograms. Lateral cephalograms of 197 untreated adults were analyzed in dental imaging software (Onyx Ceph 3™; Image Instruments, Chemnitz, Germany). Four groups were formed based on vertical (Index scores) and sagittal (individualized ANB values) parameters. Ninety-nine patients were defined as the control group due to their neutral sagittal and vertical relationships. The remaining patients were found by their vertical relationships to represent open-bite cases and were divided by their sagittal relationships into three study groups: neutral (Class I, n = 34), distal (Class II, n = 26), and mesial (Class III, n = 38). A geometric morphometric approach was used to analyze the x,y-coordinates of 28 skeletal landmarks on each cephalogram. Relative size was captured based on centroid size (CS). The shape-determining factors in the groups were compared by permutation testing after Procrustes transformation, and intergroup differences were visualized in the form of thin-plate splines. While size (CS) was significantly increased in the Class III group, the other two groups were not different from the control group. After Procrustes transformation, characteristic and invariably significant (p common that the mandibular ramus is compressed, but marked differences are seen in terms of vertical development of the maxilla. This differentiated view of open-bite cases should be taken into consideration during individual etiology assessment and treatment planning.

Cause, setting and ownership analysis of dog bites in Bay County, Florida from 2009 to 2010.

Science.gov (United States)

Matthias, J; Templin, M; Jordan, M M; Stanek, D

2015-02-01

Emergency room and hospital discharge data have been used to describe the risk factors and public health impact of dog bites. These data sets are based on financial charges for severe bites and underestimates dog bite burdens within communities. This study expands both the source of information and risk factor data collected to provide demographic analysis of dog bite injury risk factors reported in Bay County, Florida in 2009-2010. Extended data for dog bites reported by various sources from January 1, 2009 to December 31, 2010 were collected by Florida Department of Health in Bay County. Data collected included bite victim's age and gender, primary reported cause of bite, setting, dog's restraint status and relationship between the victim and the dog. A total of 799 bites were reported. Most bites (55%) were reported first by healthcare practitioners, particularly bites involving childrenmanagement was the most common cause of bites (26%), followed by protective behaviour (24%). Bites of unknown cause were 2.5 times more likely in childrenrisks by age group or gender provides an opportunity to implement targeted interventions to prevent dog bites. © 2014 Blackwell Verlag GmbH.

Oleoresin Capsicum has Potential as a Rodent Repellent in Direct Sedding Longleaf Pine

Science.gov (United States)

James P. Barnett

1998-01-01

Direct seeding of southern pines has been a versatile and inexpensive alternative to planting on many reforestation sites across the South. Successful direct seeding has required that seeds be coated with thiram to repel birds, and with endrin to repel rodents. Endrin, which is extremely toxic, is no longer produced in the United States. Therefore, a substitute is...

Postural And Eye-Positional Effects On Human Biting Force: An Experimental Study

Directory of Open Access Journals (Sweden)

Altay Tabancacı

2012-06-01

Full Text Available Muscle groups affected on biting force are called temporal muscle as a major and masseter muscle as a minor. According to the human posture stability, forces of these muscles vary with the force directions. In this case, experimental investigation is strictly important such that biting force under different postural and eye- positional situations is changed. In this study, seven-male and seven-female within the age-range of 17-24 are considered corresponding to having with restorated molar tooth and without that type of tooth. With the help of specially designed biting fork, different posture- and eye-positions are investigated for experimental biting force analysis. Changes in eye-positions are not indicated significant difference for all postural positions. On one hand, it is obtained that biting force of no-filling tooth in men becomes maximum if facial muscles give full effort to biting. On the other hand, effect of facial muscles for women is not clearly noticed depending on the postural differences.

Rat-bite fever presenting with rash and septic arthritis.

Science.gov (United States)

Kanechorn Na Ayuthaya, Rajyani; Niumpradit, Nucha

2005-11-01

Rat-bite fever is an uncommon disease known for its endemicity to occur worldwide. Although most patients tend to develop mild symptoms with improvement from conventional antibiotics, it can progress with severe complications with a mortality rate as high as 13% without proper treatment. The authors report a complicated case of rat bite-fever involving a 61-year old woman who presented with fever petechial rash, and septic arthritis following a rat bite. Initially, multiple antibiotics were administered but were not effective. As a consequence, invasive procedures such as arthrotomy and joint debridement were done and prolonged antibiotic was administered until clinical resolution. Since many cases do not have a history of rat bite and may present with fever, rashes, and arthritis it is essential to distinguish it from other diseases. Here, the authors will provide details on the etiology, clinical manifestations, diagnosis, and management to aid prompt detection and treatment of the disease.

Open Fracture of the Forearm Bones due to Horse Bite

OpenAIRE

Santoshi, John Ashutosh; Leshem, Lall

2014-01-01

Introduction: Fractures have been described mainly following falling accidents in horse-related injuries. Horse bites are uncommon accidents. We present a case of open fracture of the forearm due to horse bite. Case Report: A 35-year-old male farm-worker presented to the emergency room with alleged history of horse bite to the right forearm about 2 hours prior to presentation while feeding the horse. There was deformity of the forearm with multiple puncture wounds, deep abrasions and small...

Consumer perception of salt-reduced breads: Comparison of single and two-bites evaluation.

Science.gov (United States)

Antúnez, Lucía; Giménez, Ana; Alcaire, Florencia; Vidal, Leticia; Ares, Gastón

2017-10-01

Salt-reduction in processed products has been proposed as a high-impact intervention for reducing the sodium intake at population level. A major limitation for this approach is its potential negative impact on the sensory characteristics of products. The current practice in sensory and consumer science involves single sip/bite evaluations, which may not properly reflect the sensory experience that occurs during product consumption. In this context, the aim of the present work was to compare single and two bite evaluations of consumer sensory and hedonic perception of salt-reduced breads. Five studies with a total of 499 consumers were carried out, in which overall-liking scores of five salt-reduced bread samples were collected after the first and the second bite evaluation. In one of the studies consumers also answered a CATA (check-all-that-apply) question after the first and the second bite. Neither bite nor the interaction between samples and bite had a significant effect on hedonic scores. However, when hedonic scores were analysed separately for each bite, the overall liking scores from the second bite evaluation better reflected differences among samples according to their salt content in two of the five studies. The sensory characterization of the samples did not largely vary between the first and the second bite. Results suggest that consumers' perception of salt reduced bread samples did not largely vary between a single and a two bites evaluation. Further research is warranted in this regard, in particular considering more complex products. Copyright © 2017 Elsevier Ltd. All rights reserved.

Quantifying the Effect of Soil Water Repellency on Infiltration Parameters Using a Dry Sand

Science.gov (United States)

Shillito, R.; Berli, M.; Ghezzehei, T. A.; Kaminski, E.

2017-12-01

Water infiltration into less than perfectly wettable soils has usually been considered an exceptional case—in fact, it may be the rule. Infiltration into soils exhibiting some degree of water repellency has important implications in agricultural irrigation, post-fire runoff, golf course and landscape management, and spill and contaminant mitigation. Beginning from fundamental principles, we developed a physically-based model to quantify the effect of water repellency on infiltration parameters. Experimentally, we used a dry silica sand and treated it to achieve various known degrees of water repellency. The model was verified using data gathered from multiple upward infiltration (wicking) experiments using the treated sand. The model also allowed us to explore the effect of initial soil moisture conditions on infiltration into water-repellent soils, and the physical interpretation of the simple water drop penetration time test. These results provide a fundamental step in the physically-based understanding of how water infiltrates into a less than perfectly wettable porous media.

Characterization of Viral Communities of Biting Midges and Identification of Novel Thogotovirus Species and Rhabdovirus Genus

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Sarah Temmam

2016-03-01

Full Text Available More than two thirds of emerging viruses are of zoonotic origin, and among them RNA viruses represent the majority. Ceratopogonidae (genus Culicoides are well-known vectors of several viruses responsible for epizooties (bluetongue, epizootic haemorrhagic disease, etc.. They are also vectors of the only known virus infecting humans: the Oropouche virus. Female midges usually feed on a variety of hosts, leading to possible transmission of emerging viruses from animals to humans. In this context, we report here the analysis of RNA viral communities of Senegalese biting midges using next-generation sequencing techniques as a preliminary step toward the identification of potential viral biohazards. Sequencing of the RNA virome of three pools of Culicoides revealed the presence of a significant diversity of viruses infecting plants, insects and mammals. Several novel viruses were detected, including a novel Thogotovirus species, related but genetically distant from previously described tick-borne thogotoviruses. Novel rhabdoviruses were also detected, possibly constituting a novel Rhabdoviridae genus, and putatively restricted to insects. Sequences related to the major viruses transmitted by Culicoides, i.e., African horse sickness, bluetongue and epizootic haemorrhagic disease viruses were also detected. This study highlights the interest in monitoring the emergence and circulation of zoonoses and epizooties using their arthropod vectors.

Characterization of Viral Communities of Biting Midges and Identification of Novel Thogotovirus Species and Rhabdovirus Genus

Science.gov (United States)

Temmam, Sarah; Monteil-Bouchard, Sonia; Robert, Catherine; Baudoin, Jean-Pierre; Sambou, Masse; Aubadie-Ladrix, Maxence; Labas, Noémie; Raoult, Didier; Mediannikov, Oleg; Desnues, Christelle

2016-01-01

More than two thirds of emerging viruses are of zoonotic origin, and among them RNA viruses represent the majority. Ceratopogonidae (genus Culicoides) are well-known vectors of several viruses responsible for epizooties (bluetongue, epizootic haemorrhagic disease, etc.). They are also vectors of the only known virus infecting humans: the Oropouche virus. Female midges usually feed on a variety of hosts, leading to possible transmission of emerging viruses from animals to humans. In this context, we report here the analysis of RNA viral communities of Senegalese biting midges using next-generation sequencing techniques as a preliminary step toward the identification of potential viral biohazards. Sequencing of the RNA virome of three pools of Culicoides revealed the presence of a significant diversity of viruses infecting plants, insects and mammals. Several novel viruses were detected, including a novel Thogotovirus species, related but genetically distant from previously described tick-borne thogotoviruses. Novel rhabdoviruses were also detected, possibly constituting a novel Rhabdoviridae genus, and putatively restricted to insects. Sequences related to the major viruses transmitted by Culicoides, i.e., African horse sickness, bluetongue and epizootic haemorrhagic disease viruses were also detected. This study highlights the interest in monitoring the emergence and circulation of zoonoses and epizooties using their arthropod vectors. PMID:26978389

[Comparison of bite marks and teeth features using 2D and 3D methods].

Science.gov (United States)

Lorkiewicz-Muszyńska, Dorota; Glapiński, Mariusz; Zaba, Czesław; Łabecka, Marzena

2011-01-01

The nature of bite marks is complex. They are found at the scene of crime on different materials and surfaces - not only on human body and corpse, but also on food products and material objects. Human bites on skin are sometimes difficult to interpret and to analyze because of the specific character of skin--elastic and distortable--and because different areas of human body have different surfaces and curvatures. A bite mark left at the scene of crime can be a highly helpful way to lead investigators to criminals. The study was performed to establish: 1) whether bite marks exhibit variations in the accuracy of impressions on different materials, 2) whether it is possible to use the 3D method in the process of identifying an individual based on the comparison of bite marks revealed at the scene, and 3D scans of dental casts, 3) whether application of the 3D method allows for elimination of secondary photographic distortion of bite marks. The authors carried out experiments on simulated cases. Five volunteers bit various materials with different surfaces. Experimental bite marks were collected with emphasis on differentiations of materials. Subsequently, dental impressions were taken from five volunteers in order to prepare five sets of dental casts (the maxilla and mandible. The biting edges of teeth were impressed in wax to create an imprint. The samples of dental casts, corresponding wax bite impressions and bite marks from different materials were scanned with 2D and 3D scanners and photographs were taken. All of these were examined in detail and then compared using different methods (2D and 3D). 1) Bite marks exhibit variations in accuracy of impression on different materials. The most legible reproduction of bite marks was seen on cheese. 2) In comparison of bite marks, the 3D method and 3D scans of dental casts are highly accurate. 3) The 3D method helps to eliminate secondary photographic distortion of bite marks.

Mosquitoes meet microfluidics: High-throughput microfluidic tools for insect-parasite ecology in field conditions

Science.gov (United States)

Prakash, Manu; Mukundarajan, Haripriya

2013-11-01

A simple bite from an insect is the transmission mechanism for many deadly diseases worldwide--including malaria, yellow fever, west nile and dengue. Very little is known about how populations of numerous insect species and disease-causing parasites interact in their natural habitats due to a lack of measurement techniques. At present, vector surveillance techniques involve manual capture by using humans as live bait, which is hard to justify on ethical grounds. Individual mosquitoes are manually dissected to isolate salivary glands to detect sporozites. With typical vector infection rates being very low even in endemic areas, it is almost impossible to get an accurate picture of disease distribution, in both space and time. Here we present novel high-throughput microfluidic tools for vector surveillance, specifically mosquitoes. A two-dimensional high density array with baits provide an integrated platform for multiplex PCR for detection of both vector and parasite species. Combining techniques from engineering and field ecology, methods and tools developed here will enable high-throughput measurement of infection rates for a number of diseases in mosquito populations in field conditions. Pew Foundation.

Peatland water repellency: Importance of soil water content, moss species, and burn severity

Science.gov (United States)

Moore, P. A.; Lukenbach, M. C.; Kettridge, N.; Petrone, R. M.; Devito, K. J.; Waddington, J. M.

2017-11-01

Wildfire is the largest disturbance affecting peatlands, with northern peat reserves expected to become more vulnerable to wildfire as climate change enhances the length and severity of the fire season. Recent research suggests that high water table positions after wildfire are critical to limit atmospheric carbon losses and enable the re-establishment of keystone peatland mosses (i.e. Sphagnum). Post-fire recovery of the moss surface in Sphagnum-feathermoss peatlands, however, has been shown to be limited where moss type and burn severity interact to result in a water repellent surface. While in situ measurements of moss water repellency in peatlands have been shown to be greater for feathermoss in both a burned and unburned state in comparison to Sphagnum moss, it is difficult to separate the effect of water content from species. Consequently, we carried out a laboratory based drying experiment where we compared the water repellency of two dominant peatland moss species, Sphagnum and feathermoss, for several burn severity classes including unburned samples. The results suggest that water repellency in moss is primarily controlled by water content, where a sharp threshold exists at gravimetric water contents (GWC) lower than ∼1.4 g g-1. While GWC is shown to be a strong predictor of water repellency, the effect is enhanced by burning. Based on soil water retention curves, we suggest that it is highly unlikely that Sphagnum will exhibit strong hydrophobic conditions under field conditions.

Organic compounds in hot-water-soluble fractions from water repellent soils

Science.gov (United States)

Atanassova, Irena; Doerr, Stefan

2014-05-01

Water repellency (WR) is a soil property providing hydrophobic protection and preventing rapid microbial decomposition of organic matter entering the soil with litter or plant residues. Global warming can cause changes in WR, thus influencing water storage and plant productivity. Here we assess two different approaches for analysis of organic compounds composition in hot water extracts from accelerated solvent extraction (ASE) of water repellent soils. Extracts were lyophilized, fractionated on SiO2 (sand) and SPE cartridge, and measured by GC/MS. Dominant compounds were aromatic acids, short chain dicarboxylic acids (C4-C9), sugars, short chain fatty acids (C8-C18), and esters of stearic and palmitic acids. Polar compounds (mainly sugars) were adsorbed on applying SPE clean-up procedure, while esters were highly abundant. In addition to the removal of polar compounds, hydrophobic esters and hydrocarbons (alkanes and alkenes particle wettability and C dynamics in soils. Key words: soil water repellency, hot water soluble carbon (HWSC), GC/MS, hydrophobic compounds

Extreme skeletal open bite correction with vertical elastics.

Science.gov (United States)

Cruz-Escalante, Marco Antonio; Aliaga-Del Castillo, Aron; Soldevilla, Luciano; Janson, Guilherme; Yatabe, Marilia; Zuazola, Ricardo Voss

2017-11-01

Severe skeletal open bites may be ideally treated with a combined surgical-orthodontic approach. Alternatively, compensations may be planned to camouflage the malocclusion with orthodontics alone. This case report describes the treatment of an 18-year-old man who presented with a severe open bite involving the anterior and posterior teeth up to the first molars, increased vertical dimension, bilateral Class III molar relationship, bilateral posterior crossbite, dental midline deviation, and absence of the maxillary right canine and the mandibular left first premolar. A treatment plan including the extraction of the mandibular right first premolar and based on uprighting and vertical control of the posterior teeth, combined with extrusion of the anterior teeth using multiloop edgewise archwire mechanics and elastics was chosen. After 6 months of alignment and 2 months of multiloop edgewise archwire mechanics, the open bite was significantly reduced. After 24 months of treatment, anterior teeth extrusion, posterior teeth intrusion, and counterclockwise mandibular rotation were accomplished. Satisfactory improvement of the overbite, overjet, sagittal malocclusion, and facial appearance were achieved. The mechanics used in this clinical case demonstrated good and stable results for open-bite correction at the 2-year posttreatment follow-up.

Repellent Activity of Eight Essential Oils of Chinese Medicinal Herbs t oBlattella germanica L.

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Zhi Long Liu

2011-01-01

Full Text Available Eight e ssential oil s of Chinese medicinal herbs ( Angelica sinensis , Curuma aeruginosa , Cyperus rotundus , Eucalyptus robusta , Illicium verum , Lindera aggregate , Ocimum basilicum , and Zanthoxylum bungeanum w ere obtained by hydrodistillation and the essential oil of Eucalyptus robusta leaves was analyzed by gas chromatography-mass spectrometry (GC-MS. A total of 22 components of the essential oil of E. robusta were identified. The principal compounds in E . robusta essential oil were α- p inene (28.74% and 1,8- c ineole (27.18%, spathulenol (6.63%, globulol (6.53% and ρ - m enth-1-en-8-ol (5.20%. The 8 essential oil s and two main components, α -pinene and 1, 8-cineole of the essential oil of E. robusta were evaluated repellency against nymphs of the German cockroaches . Strong repellency (Class V was obtained for Cyperus rotundus and Eucalyptus robusta essential oils and α- p inene and 1, 8- c ineole . However, Illicium verum essential oil possessed weak (Class I repellency. At a concentration of 5 ppm, all the 8 essential oils and the two compounds showed repellent activity after one hour exposure. At 1 ppm concentration, essential oil of Cyperus rotundus showed strong repellency and Class IV repellency was obtained for essential oil of E. robusta and the two compounds after one hour exposure. However, essential oils of I . verum and Lindera aggregata showed strong attractiveness to the German cockroaches at a concentration of 1 ppm .

Arthropod-Borne Diseases: The Camper's Uninvited Guests.

Science.gov (United States)

Juckett, Gregory

2015-08-01

Arthropod-borne diseases are a major problem whenever outdoor activities bring arthropods and people into contact. The arthropods discussed here include arachnids (ticks) and insects. Most arthropod bites and stings are minor, with the notable exception being bee-sting anaphylaxis. Ticks cause the most disease transmission. Key hard tick vectors include black-legged (Ixodes), dog (Dermacentor), and lone star (Amblyomma) ticks, which transmit Lyme and various rickettsial diseases. Insect repellents, permethrin sprays, and proper tick inspection reduce this risk significantly. Lyme disease and the milder southern-tick-associated rash illness (STARI) are characterized by the erythema migrans rash followed, in the case of Lyme disease, by early, disseminated, and late systemic symptoms. Treatment is with doxycycline or ceftriaxone. Indefinite treatment of "chronic Lyme disease" based on subjective symptoms is not beneficial. Rickettsial diseases include ehrlichiosis, anaplasmosis, and Rocky Mountain spotted fever, which are characterized by fever, headache, and possible rash and should be empirically treated with doxycycline while awaiting laboratory confirmation. Tularemia is a bacterial disease (Francisella) spread by ticks and rabbits and characterized by fever and adenopathy. Treatment is with gentamicin or streptomycin. Babesiosis is a protozoal disease, mimicking malaria, that causes a self-limited flu-like disease in healthy hosts but can be life threatening with immune compromise. Treatment is with atovaquone and azithromycin. Other tick-related conditions include viral diseases (Powassan, Colorado tick fever, heartland virus), tick-borne relapsing fever (Borrelia), and tick paralysis (toxin). Mosquitoes, lice, fleas, and mites are notable for their annoying bites but are increasingly significant disease vectors even in the United States.

Bug bites and stings: When to see a dermatologist

Medline Plus

Full Text Available ... correct dose. For bites that itch , apply an ice pack or an over-the-counter anti-itch cream, such as hydrocortisone. Another option is to take an over-the-counter oral antihistamine. To reduce swelling , apply an ice pack to the bite. If you experience any ...

Experimental Investigation of 2D thermal signature and 3D X-Ray Computed Tomography in contrasting Wettable and Water-Repellent Beads

Science.gov (United States)

Alsih, Abdulkareem; Flavel, Richard; McGrath, Gavan

2017-04-01

This study presents experimental results investigating spatial patterns of infiltration and evaporation in heterogeneous water repellent media. Infrared camera measurements and 3D X-ray computed tomography imaging was performed across wet-dry cycles on glass beads with engineered patches of water repellence. The imaging revealed spatial variability in infiltration and the redistribution of water in the media resulting in differences in relative evaporation rates during drying. It appears that the spatial organization of the heterogeneity play a role in the breakdown of water repellence at the interface of the two media. This suggests a potential mechanism for self-organization of repellency spatial patterns in field soils. At the interface between wettable and water repellent beads a lateral drying front propagates towards the wettable beads from the repellent beads. During this drying the relative surface temperatures change from a relatively cooler repellent media surface to a relatively cooler wettable media surface indicating the changes in evaporative water loss between the beads of varying water repellence. The lateral drying front was confirmed using thermography in a small-scale model of glass beads with chemically induced repellence and then subjected to 3D X-ray imaging. Pore-scale imaging identified the hydrology at the interface of the two media and at the drying front giving insights into the physics of water flow in water repellent soil.

Feeding biomechanics and theoretical calculations of bite force in bull sharks (Carcharhinus leucas) during ontogeny.

Science.gov (United States)

Habegger, Maria L; Motta, Philip J; Huber, Daniel R; Dean, Mason N

2012-12-01

Evaluations of bite force, either measured directly or calculated theoretically, have been used to investigate the maximum feeding performance of a wide variety of vertebrates. However, bite force studies of fishes have focused primarily on small species due to the intractable nature of large apex predators. More massive muscles can generate higher forces and many of these fishes attain immense sizes; it is unclear how much of their biting performance is driven purely by dramatic ontogenetic increases in body size versus size-specific selection for enhanced feeding performance. In this study, we investigated biting performance and feeding biomechanics of immature and mature individuals from an ontogenetic series of an apex predator, the bull shark, Carcharhinus leucas (73-285cm total length). Theoretical bite force ranged from 36 to 2128N at the most anterior bite point, and 170 to 5914N at the most posterior bite point over the ontogenetic series. Scaling patterns differed among the two age groups investigated; immature bull shark bite force scaled with positive allometry, whereas adult bite force scaled isometrically. When the bite force of C. leucas was compared to those of 12 other cartilaginous fishes, bull sharks presented the highest mass-specific bite force, greater than that of the white shark or the great hammerhead shark. A phylogenetic independent contrast analysis of anatomical and dietary variables as determinants of bite force in these 13 species indicated that the evolution of large adult bite forces in cartilaginous fishes is linked predominantly to the evolution of large body size. Multiple regressions based on mass-specific standardized contrasts suggest that the evolution of high bite forces in Chondrichthyes is further correlated with hypertrophication of the jaw adductors, increased leverage for anterior biting, and widening of the head. Lastly, we discuss the ecological significance of positive allometry in bite force as a possible

REPELLENT AND OVIPOSITION DETERRENT ACTIVITIES OFTHE ESSENTIAL OIL FROM MIKANIA MICRANTHA AND ITS COMPOUNDS ON PLUTELLA XYLOSTELLA

Institute of Scientific and Technical Information of China (English)

Mao-xinZhang; BingLing; Shao-yingChen; Guang-wenLiang; Xiong-feiPang

2004-01-01

Repellent and oviposition deterrent activities of the essential oil from Mikania micrantha and five volatile compounds including limonene, a-terpinene, linalool, B-caryophylene and verbenone on the diamondback moth (DBM), Plutella xylostella, was investigated in door and in net-house. The results showed that the essential oil of the M. micrantha had significant repellant effect (at flow 100-180 mL/min) and oviposition deterrent activity at dose 1020 uL/seedling for the DBM. In five volatile compounds, a-terpinene, limonene and linalool had significant effect on repellent and oviposition deterrent of the DBM moths, but verbenone and B-caryophylene, no significantly effect was observed in repellent and oviposition deterrent.

The epidemiology of bite and scratch injuries by vertebrate animals in Switzerland

International Nuclear Information System (INIS)

Matter, Hans C.

1998-01-01

Pet and wildlife populations are a potential source of various public health problems, and injuries and complications due to animal bites and scratches are the most obvious. As no population based data on the frequency of animal bites were available at a national level in Switzerland, a study was conducted by the Swiss Sentinel Surveillance Network. The objectives of this study were to estimate the incidence of medical consultations due to bite and scratch injuries in humans caused by vertebrate animals, to identify possible risk factors, and to assess bite management habits in primary health care. An annual bite and scratch incidence rate of 325 per 100,000 population was estimated. Consultations peaked during the summer months and geographical differences in the reported incidence were observed. Dogs accounted for more than 60% and cats for about 25% of all cases reported. Animal bites and scratches were frequent in persons under 20 years of age. In most ages, the incidence was higher among women than among men, but not in children under the age of ten years. The incidence of cat bites was especially high in adult women. Bites to the head and neck were most frequent in infants and young children and accounted for approximately one third of the reported cases in this age group. Patients sought medical care principally for primary wound care (52.0%) and for vaccination advice (29.6%). Rabies postexposure prophylaxis was initiated in 1.1% of patients. Wound infection was reported in 10.9% of cases, with cat bites/scratches being more often infected than injuries due to dogs. Hospitalization was reported in 0.3% of patients. Data from the emergency department of two district hospitals showed that head and neck injuries were more frequent in out-patients and a higher proportion of persons presented with wound infections (14.1%). The hospitalization rate for emergency department visits was 4.7%. Animal bites and scratches are common events in Switzerland. They

'Natural background' soil water repellency in conifer forests of the north-western USA: Its prediction and relationship to wildfire occurrence

Science.gov (United States)

Doerr, S.H.; Woods, S.W.; Martin, D.A.; Casimiro, M.

2009-01-01

Soils under a wide range of vegetation types exhibit water repellency following the passage of a fire. This is viewed by many as one of the main causes for accelerated post-fire runoff and soil erosion and it has often been assumed that strong soil water repellency present after wildfire is fire-induced. However, high levels of repellency have also been reported under vegetation types not affected by fire, and the question arises to what degree the water repellency observed at burnt sites actually results from fire. This study aimed at determining 'natural background' water repellency in common coniferous forest types in the north-western USA. Mature or semi-mature coniferous forest sites (n = 81), which showed no evidence of recent fires and had at least some needle cast cover, were sampled across six states. After careful removal of litter and duff at each site, soil water repellency was examined in situ at the mineral soil surface using the Water Drop Penetration Time (WDPT) method for three sub-sites, followed by collecting near-surface mineral soil layer samples (0-3 cm depth). Following air-drying, samples were further analyzed for repellency using WDPT and contact angle (??sl) measurements. Amongst other variables examined were dominant tree type, ground vegetation, litter and duff layer depth, slope angle and aspect, elevation, geology, and soil texture, organic carbon content and pH. 'Natural background' water repellency (WDPT > 5 s) was detected in situ and on air-dry samples at 75% of all sites examined irrespective of dominant tree species (Pinus ponderosa, Pinus contorta, Picea engelmanii and Pseudotsuga menziesii). These findings demonstrate that the soil water repellency commonly observed in these forest types following burning is not necessarily the result of recent fire but can instead be a natural characteristic. The notion of a low background water repellency being typical for long-unburnt conifer forest soils of the north-western USA is

Interactive relationship between the mechanical properties of food and the human response during the first bite.

Science.gov (United States)

Dan, Haruka; Kohyama, Kaoru

2007-05-01

Biting is an action that results from interplay between food properties and the masticatory system. The mechanical factors of food that cause biting adaptation and the recursive effects of modified biting on the mechanical phenomena of food are largely unknown. We examined the complex interaction between the bite system and the mechanical properties. Nine subjects were each given a cheese sample and instructed to bite it once with their molar teeth. An intra-oral bite force-time profile was measured using a tactile pressure-measurement system with a sheet sensor inserted between the molars. Time, force, and impulse for the first peak were specified as intra-oral parameters of the sample fracture. Mechanical properties of the samples were also examined using a universal testing machine at various test speeds. Besides fracture parameters, initial slope was also determined as a mechanical property possibly sensed shortly after bite onset. The bite profile was then examined based on the mechanical parameters. Sample-specific bite velocities were identified as characteristic responses of a human bite. A negative correlation was found between bite velocity and initial slope of the sample, suggesting that the initial slope is the mechanical factor that modifies the consequent bite velocity. The sample-specific bite velocity had recursive effects on the following fracture event, such that a slow velocity induced a low bite force and high impulse for the intra-oral fracture event. We demonstrated that examination of the physiological and mechanical factors during the first bite can provide valuable information about the food-oral interaction.

Effects of strong bite force on the facial vertical dimension of pembarong performers

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C. Christina

2017-06-01

Full Text Available Background: A pembarong performer is a reog dancer who bites on a piece of wood inserted into his/her mouth in order to support a 60 kg Barongan or Dadak Merak mask. The teeth supporting this large and heavy mask are directly affected, as the strong bite force exerted during a dance could affect their vertical and sagital facial dimensions. Purpose: This study aimed to examine the influence of the bite force of pembarong performers due to their vertical and sagital facial dimensions. Methods: The study reported here involved fifteen pembarong performers and thirteen individuals with normal occlusion (with specific criteria. The bite force of these subjects was measured with a dental prescale sensor during its centric occlusion. A cephalometric variation measurement was subsequently performed on all subjects with its effects on their vertical and sagital facial dimensions being measured. Results: The bite force value of the pembarong performers was 394.3816 ± 7.68787 Newtons, while the normal occlusion was 371.7784 ± 4.77791 Newtons. There was no correlation between the bite force and the facial sagital dimension of these subjects. However, a significant correlation did exist between bite force and lower facial height/total facial height (LFH/TFH ratio (p = 0.013. Conversely, no significant correlation between bite force and posterior facial height/total facial height (PFH/TFH ratio (p = 0.785 was detected. There was an inverse correlation between bite force and LFH/TFH ratio (r = -.464. Conclusion: Bite force is directly related to the decrease in LFH/TFH ratio. Occlusal pressure exerted by the posterior teeth on the alveolar bone may increase bone density at the endosteal surface of cortical bone.

Epidemiological Study of Animal Bite in Students in Hashtrood Town: 2006- 2010

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Javad Babaie

2015-08-01

Full Text Available Background and objectives : Rabies is an acute and fatal infectious disease that is very important due to high economic losses to livestock and the amounts of expenditures that are paid for purchasing serum and vaccine. The main way of disease transmitting is bites by rabid animals. Animal bite is an important threat for human health. The main aim of this research was epidemiological study of animal bite in the students of Hashtrood town. Material and Methods : In this cross-sectional study, animal bitten students’ data were collected trough the records of Hashtrood health centers registry lists between 2006-2009. The census data collecting method was used and the data were analyzed with statistical software SPSS15. Results : The incidence of animal bites in the past 5 years was 9.07 per 1,000 students. From 439 animal bitten students, 80.9% were male and 19.1% were female. According to the results, 88.4% were rural and 11.2% were urban residents. Dogs bite was the cause of 87.92%. In 86.5% of the cases, the bite was superficial and in 8.4% of the cases, bites were deeper. Among them, 16.6% received anti rabies serum, 16.2% received vaccine. This study showed that 4.8% had a previous history of bite. Of total, 78.8% made a visit to health centers in the first 24 hours, 11.4% within 25 to 48 hours, and 3.6% within 49 to 72 hours after bites. There was no human death report from rabies. Results showed that 95.2% were given incomplete vaccination and 4.1% had received five complete vaccines. Conclusion : Regarding the high prevalence of animal bites among students, educating students about the importance of rabies, students’ behavior with dogs and immediate visit to health centers after exposure to dogs should be taken serious. Restraining dogs by training dog owners and legal means should be attempted.

Facial dog bite injuries in children: A case report

Directory of Open Access Journals (Sweden)

Alessandro Leite Cavalcanti

Full Text Available Introduction: Dog bites are common and can affect victims of different ages, from children to the elderly. Injuries are usually located in different body regions, including head and face. The treatment of choice for injuries is the suture of the lesion, accompanied by antibiotic therapy and tetanus and anti-rabies vaccination. Presentation of case: An 11-year-old male black patient was admitted to the Surgery and Maxillo-Facial Traumatology Service, on an urgent basis, victim of domestic animal aggression (dog biting. The child had multiple and extensive lesions on the face, trauma with laceration with loss of substance, involving the left genic region, lower and upper lip, and lower gingival-labial sulcus. Discussion: Smaller children are especially vulnerable to injuries in the craniofacial region due their low stature, propensity to crawl/play on the ground and exploratory behavior. The primary treatment of bites is by means of direct suture, grafting or local flaps, depending on the type of wound and the surgeon's decision, regardless of time elapsed from the attack. Conclusion: This case shows a case of a child patient victim of animal bite, with lesions limited to the region of the face. The patient was followed up for a month and showed good wound healing without any complications. Keywords: Wounds and injuries, Bites and stings, Maxillofacial injuries, Dogs

Critical homoclinic orbits lead to snap-back repellers

International Nuclear Information System (INIS)

Gardini, Laura; Sushko, Iryna; Avrutin, Viktor; Schanz, Michael

2011-01-01

Highlights: → We consider critical homoclinic orbits in continuous and discontinuous maps. → Unbounded homoclinic orbits in maps on unbounded domains are considered as well. → We show that a snapback-repeller (SBR) with a non-critical homoclinic orbit implies chaos. → We show also that a SBR with a critical homoclinic orbit may or may not imply chaos. - Abstract: When nondegenerate homoclinic orbits to an expanding fixed point of a map f:X→X,X subset or equal R n , exist, the point is called a snap-back repeller. It is known that the relevance of a snap-back repeller (in its original definition) is due to the fact that it implies the existence of an invariant set on which the map is chaotic. However, when does the first homoclinic orbit appear? When can other homoclinic explosions, i.e., appearance of infinitely many new homoclinic orbits, occur? As noticed by many authors, these problems are still open. In this work we characterize these bifurcations, for any kind of map, smooth or piecewise smooth, continuous or discontinuous, defined in a bounded or unbounded closed set. We define a noncritical homoclinic orbit and a homoclinic orbit of an expanding fixed point is structurally stable iff it is noncritical. That is, only critical homoclinic orbits are responsible for the homoclinic explosions. The possible kinds of critical homoclinic orbits will be also investigated, as well as their dynamic role.

Initial water repellency affected organic matter depletion rates of manure amended soils in Sri Lanka

Directory of Open Access Journals (Sweden)

Leelamanie D.A.L.

2014-12-01