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1.
Insectes Soc ; 70(2): 259-263, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37273892

RESUMO

The little fire ant (LFA), Wasmannia auropunctata, is a serious invasive pest first reported on Hawaii Island in 1999, and has since spread and established itself across the island. LFA is considered one of the worst 100 invasive species and has significant ecological, agricultural, and public health impacts in invaded areas, which include much of the tropical New World. Although localized eradication efforts have proven successful, they are intensive and difficult to implement. Furthermore, LFA's high invasive-ability resists these control efforts in areas where the species is established and can re-infest treated areas. This research set out to determine whether LFA queens have a suppressant effect on new queen production in nests, as a first step in identifying a potential queen pheromone for LFA. A queen pheromone could offer a means to shutdown LFA reproductive capability, potentially by suppressing the production of new queens or inducing the execution of queens or queen-destined larvae. When queenless experimental nests and polygyne experimental nests were compared, six out of eight queenless nests successfully reared both new alate queens (2.25 queens/nest) and drones (3.63 drones/nest) to adulthood, whereas only three of eight polygyne nests reared sexual larvae that failed to develop to adulthood or even the pupal stage. These results suggest that dealate mature LFA queens suppress the production of new alate queens in LFA nests, and is the first evidence that LFA may utilize a queen pheromone.

2.
Virus Genes ; 59(2): 276-289, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36729322

RESUMO

Despite being one of the most destructive invasive species of ants, only two natural enemies are known currently for Wasmannia auropunctata, commonly known as the electric ant or little fire ant. Because viruses can be effective biological control agents against many insect pests, including ants, a metagenomics/next-generation sequencing approach was used to facilitate discovery of virus sequences from the transcriptomes of W. auropunctata. Five new and complete positive sense, single-stranded RNA virus genomes, and one new negative sense, single-stranded RNA virus genome were identified, sequenced, and characterized from W. auropunctata collected in Argentina by this approach, including a dicistrovirus (Electric ant dicistrovirus), two polycipiviruses (Electric ant polycipivirus 1; Electric ant polycipivirus 2), a solinvivirus (Electric ant solinvivirus), a divergent genome with similarity to an unclassified group in the Picornavirales (Electric ant virus 1), and a rhabdovirus (Electric ant rhabdovirus). An additional virus genome was detected that is likely Solenopsis invicta virus 10 (MH727527). The virus genome sequences were absent from the transcriptomes of W. auropunctata collected in the USA (Hawaii and Florida). Additional limited field surveys corroborated the absence of these viruses in regions where the electric ant is invasive (the USA and Australia). The replicative genome strand of four of the viruses (Electric ant polycipivirus 2, Electric ant solinvivirus, Electric ant virus 1, and Solenopsis invicta virus 10 (in the electric ant) was detected in Argentinean-collected W. auropunctata indicating that the ant is a host for these viruses. These are the first virus discoveries to be made from W. auropunctata.


Assuntos
Formigas , Vírus de RNA , Animais , Vírus de RNA/genética , Genoma Viral/genética , Metagenômica , RNA
3.
J Chem Ecol ; 45(4): 339-347, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30854612

RESUMO

We report the identification of p-mentha-1,3-dien-8-ol, an unstable monoterpene alcohol, as a male-produced aggregation-sex pheromone component of the cerambycid beetle Paranoplium gracile (Leconte) (subfamily Cerambycinae, tribe Oemini), a species endemic to California. Headspace volatiles from live males contained a blend of nine cyclic terpenoids that were not detected in analogous samples from females. Volatiles produced by male Eudistenia costipennis Fall, also in the tribe Oemini, contained the same suite of nine compounds. Four compounds, dehydro-p-cymene, p-mentha-1,3-dien-8-ol, p,α,α-trimethylbenzyl alcohol, and an unidentified compound were found to elicit responses from antennae of P. gracile females in coupled gas chromatography-electroantennogram detection (GC-EAD) assays, whereas only p-mentha-1,3-dien-8-ol elicited responses from antennae of males. In field assays, p-mentha-1,3-dien-8-ol stabilized with the antioxidant butylated hydroxytoluene (BHT) attracted P. gracile of both sexes, indicating it functions as an aggregation-sex pheromone, as with other pheromones identified from its subfamily, the Cerambycinae. Adding four of the other compounds found in headspace samples to the dienol lure had no effect on attraction. Because of the instability of p-mentha-1,3-dien-8-ol, it seems likely that at least some of the compounds seen in the extracts of volatiles from both species are artefacts, rather than being components of the pheromone.


Assuntos
Álcoois/metabolismo , Besouros/metabolismo , Monoterpenos/metabolismo , Atrativos Sexuais/metabolismo , Álcoois/química , Animais , Antenas de Artrópodes/metabolismo , Cromatografia Gasosa/métodos , Besouros/classificação , Feminino , Masculino , Especificidade da Espécie
4.
J Chem Ecol ; 45(3): 217-226, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30706280

RESUMO

Many species of longhorn beetles (Coleoptera: Cerambycidae) utilize male-produced aggregation-sex pheromones that attract both sexes. However, the reasons why and the details of how this type of pheromone is used by cerambycids and other coleopteran species that utilize analogous male-produced pheromones remain unclear. Thus, our goals were to test the hypotheses that 1) cerambycids respond to pheromones in a dose-dependent (= release rate-dependent) manner and 2) pheromone emission is density-dependent. If true, these characteristics of pheromone use could suggest that cerambycids utilize an optimal density strategy to limit competition for scarce and ephemeral hosts, i.e., the stressed or dying trees that typically constitute their larval hosts. Attraction of beetles to a range of release rates of two common pheromone components - 2-methylbutanol and 3-hydroxyhexan-2-one - was tested in field trials. Responses, as measured by the number of beetles caught in pheromone-baited traps, increased with release rates for five endemic species, even at the highest rates tested (~1450 µg/h for 2-methylbutanol and ~720 µg/h for 3-hydroxyhexan-2-one). The effect of density of conspecific males on per capita pheromone production was tested by collecting the volatiles produced by individuals, pairs, or groups of three or four male Phymatodes grandis Casey. Frequency of pheromone production was significantly different among the treatment densities, and emission rates of the pheromone (R)-2-methylbutanol decreased with increasing density. These results are discussed in the context of a possible optimal density strategy used by cerambycids, and more broadly, in relation to the use of male-produced aggregation-sex pheromones by other coleopterans. In addition, we report the identification of the pheromones of four of our five test species, specifically, Phymatodes obliquus Casey, Brothylus conspersus LeConte, Brothylus gemmulatus LeConte, and Xylotrechus albonotatus Casey.


Assuntos
Besouros/fisiologia , Atrativos Sexuais/metabolismo , Animais , Besouros/classificação , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Hexanonas/metabolismo , Masculino , Pentanóis/metabolismo , Especificidade da Espécie , Compostos Orgânicos Voláteis/metabolismo
5.
Environ Entomol ; 47(5): 1300-1305, 2018 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-29986003

RESUMO

In field trials testing attraction of cerambycid beetles to a blend of known pheromone components plus host plant volatiles, several species in the subfamily Spondylidinae were attracted to baited traps, suggesting that one or more components of the blend might constitute their pheromones. Here, we describe laboratory and field experiments aimed at identifying the actual pheromone components produced by these species. Analysis of headspace odors collected from male Tetropium abietis (Fall) (Coleoptera: Cerambycidae) contained (S)-fuscumol as a single component, whereas Asemum nitidum (LeConte) (Coleoptera: Cerambycidae) males produced both (S)-fuscumol and geranylacetone, and Asemum caseyi (Linsley) (Coleoptera: Cerambycidae) produced only geranylacetone. In field trials testing fuscumol, fuscumol acetate, and geranylacetone as individual components or in blends, in combination with host plant volatiles, A. nitidum were attracted to blends of fuscumol and geranylacetone, T. abietis were attracted to fuscumol alone, and A. caseyi were attracted to geranylacetone alone. Fuscumol acetate did not appear to be either attractive or inhibitory. These results, along with previous catches of spondylidine species in traps baited with fuscumol, provide evidence that fuscumol and geranylacetone are likely to be relatively common pheromone structures for species in the subfamily Spondylidinae.


Assuntos
Besouros , Feromônios , Terpenos , Animais , Feminino , Masculino
6.
J Econ Entomol ; 111(4): 1644-1649, 2018 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-29668952

RESUMO

Methyl eugenol (ME) is a powerful semiochemical attractant to males of the oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), and is the keystone of detection, control, and eradication programs against this polyphagous and highly invasive tephritid pest. Despite its status as a model lure against B. dorsalis, variation among individuals in their attraction is known, independent of the generally increasing attraction with age and decreases with previous exposure. Here we report that adult male B. dorsalis that fed on Terminalia catappa L. (Myrtales: Combretaceae) (tropical almond) fruit as larvae have a significantly lower behavioral response to ME compared with wild males from Psidium guajava L. (Myrtales: Myrtaceae) or colony-reared males raised on artificial larval diet. F1 males from the tropical almond stock reared on artificial larval diet did not show reduced attraction to ME, suggesting that the lowered response of parental males (sires) results from the host fruit itself, perhaps its relatively high amount of ME. Experiments with ME added to artificial diet lend some support to this interpretation. In addition to the results above, we report on quantities of ME in three different host fruits (T. catappa, P. guajava, and Carica papaya L. (Brassicales: Caricaceae)) of B. dorsalis. This study indicates the need for further research on the effect of host fruit on adult response to lures in economically important tephritids.


Assuntos
Tephritidae , Terminalia , Animais , Eugenol/análogos & derivados , Controle de Insetos , Larva , Masculino
7.
J Chem Ecol ; 44(4): 327-338, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29479642

RESUMO

To date, all known or suspected pheromones of click beetles (Coleoptera: Elateridae) have been identified solely from species native to Europe and Asia; reports of identifications from North American species dating from the 1970s have since proven to be incorrect. While conducting bioassays of pheromones of a longhorned beetle (Coleoptera: Cerambycidae), we serendipitously discovered that males of Cardiophorus tenebrosus L. and Cardiophorus edwardsi Horn were specifically attracted to the cerambycid pheromone fuscumol acetate, (E)-6,10-dimethylundeca-5,9-dien-2-yl acetate, suggesting that this compound might also be a sex pheromone for the two Cardiophorus species. Further field bioassays and electrophysiological assays with the enantiomers of fuscumol acetate determined that males were specifically attracted by the (R)-enantiomer. However, subsequent analyses of extracts of volatiles from female C. tenebrosus and C. edwardsi showed that the females actually produced a different compound, which was identified as (3R,6E)-3,7,11-trimethyl-6,10-dodecadienoic acid methyl ester (methyl (3R,6E)-2,3-dihydrofarnesoate). In field trials, both the racemate and the (R)-enantiomer of the pheromone attracted similar numbers of male beetles, suggesting that the (S)-enantiomer was not interfering with responses to the insect-produced (R)-enantiomer. This report constitutes the first conclusive identification of sex pheromones for any North American click beetle species. Possible reasons for the strong and specific attraction of males to fuscumol acetate, which is markedly different in structure to the actual pheromone, are discussed.


Assuntos
Besouros/fisiologia , Atrativos Sexuais/química , Animais , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Cromatografia Gasosa , Ácidos Graxos Insaturados/química , Ácidos Graxos Insaturados/isolamento & purificação , Ácidos Graxos Insaturados/farmacologia , Feminino , Masculino , América do Norte , Feromônios/química , Feromônios/isolamento & purificação , Feromônios/farmacologia , Atrativos Sexuais/farmacologia , Microextração em Fase Sólida , Estereoisomerismo , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/isolamento & purificação
8.
PLoS One ; 11(9): e0162197, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27583519

RESUMO

Mountain pine beetle (Dendroctonus ponderosae) has killed millions of hectares of pine forests in western North America. Beetle success is dependent upon a community of symbiotic fungi comprised of Grosmannia clavigera, Ophiostoma montium, and Leptographium longiclavatum. Factors regulating the dynamics of this community during pine infection are largely unknown. However, fungal volatile organic compounds (FVOCs) help shape fungal interactions in model and agricultural systems and thus may be important drivers of interactions among bark beetle-associated fungi. We investigated whether FVOCs can mediate interspecific interactions among mountain pine beetle's fungal symbionts by affecting fungal growth and reproduction. Headspace volatiles were collected and identified to determine species-specific volatile profiles. Interspecific effects of volatiles on fungal growth and conidia production were assessed by pairing physically-separated fungal cultures grown either on a carbon-poor or -rich substrate, inside a shared-headspace environment. Fungal VOC profiles differed by species and influenced the growth and/or conidia production of the other species. Further, our results showed that FVOCs can be used as carbon sources for fungi developing on carbon-poor substrates. This is the first report demonstrating that FVOCs can drive interactions among bark beetle fungal symbionts, and thus are important factors in beetle attack success.


Assuntos
Carbono/química , Besouros/fisiologia , Fungos/fisiologia , Simbiose , Compostos Orgânicos Voláteis/química , Animais , Besouros/microbiologia
9.
J Chem Ecol ; 42(3): 215-29, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26980612

RESUMO

Host plant volatiles have been shown to strongly synergize the attraction of some longhorn beetle species (Coleoptera: Cerambycidae) to their pheromones. This synergism is well documented among species that infest conifers, but less so for angiosperm-infesting species. To explore the extent of this phenomenon in the Cerambycidae, we first tested the responses of a cerambycid community to a generic pheromone blend in the presence or absence of chipped material from host plants as a source of host volatiles. In the second phase, blends of oak and conifer volatiles were reconstructed, and tested at low, medium, and high release rates with the pheromone blend. For conifer-infesting species in the subfamilies Spondylidinae and Lamiinae, conifer volatiles released at the high rate synergized attraction of some species to the pheromone blend. When comparing high-release rate conifer blend with high-release rate α-pinene as a single component, species responses varied, with Asemum nitidum LeConte being most attracted to pheromones plus α-pinene, whereas Neospondylis upiformis (Mannerheim) were most attracted to pheromones plus conifer blend and ethanol. For oak-infesting species in the subfamily Cerambycinae, with the exception of Phymatodes grandis Casey, which were most attracted to pheromones plus ethanol, neither synthetic oak blend nor ethanol increased attraction to pheromones. The results indicate that the responses to combinations of pheromones with host plant volatiles varied from synergistic to antagonistic, depending on beetle species. Release rates of host plant volatiles also were important, with some high release rates being antagonistic for oak-infesting species, but acting synergistically for conifer-infesting species.


Assuntos
Comportamento Animal , Besouros/fisiologia , Feromônios/metabolismo , Plantas/metabolismo , Volatilização , Animais , Bioensaio , Cromatografia Gasosa
10.
Sante ; 8(6): 411-6, 1998.
Artigo em Francês | MEDLINE | ID: mdl-10064913

RESUMO

We studied colonial medical practices and health policies in West Africa, which has faced endemics and epidemics that have affected entire societies. We found that attempts to centralize the organization of colonial medicine, which began in the late 19th Century, were limited until the end of World War I. Research and control programs expanded after 1920, concentrating on epidemics, but largely ignoring many major health problems, such as measles, whooping cough and malnutrition, the importance of which were not recognized until after World War II. This appraisal of colonial medicine highlights the difficulties of introducing modern medicine and its ideas into African societies. There have been various social reactions, resulting in the current duality in which traditional and modern medicine coexist.


Assuntos
Colonialismo/história , História do Século XIX , História do Século XX , África Ocidental , França , Política de Saúde/história , Medicina Tradicional/história
11.
Sante ; 8(6): 411-6, 1998 Nov.
Artigo em Francês | MEDLINE | ID: mdl-9917563

RESUMO

We studied colonial medical practices and health policies in West Africa, which has faced endemics and epidemics that have affected entire societies. We found that attempts to centralize the organization of colonial medicine, which began in the late 19th Century, were limited until the end of World War I. Research and control programs expanded after 1920, concentrating on epidemics, but largely ignoring many major health problems, such as measles, whooping cough and malnutrition, the importance of which were not recognized until after World War II. This appraisal of colonial medicine highlights the difficulties of introducing modern medicine and its ideas into African societies. There have been various social reactions, resulting in the current duality in which traditional and modern medicine coexist.

12.
Soc Sci Med ; 42(3): 325-38, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8658228

RESUMO

Patient records from the Thiaroye mental hospital in Senegal were analyzed to see if the patterns of persons accompanying patients to the hospital could help portray the community's response to mental illness. A systematic sample of 935 records of initial our-patient visits were examined. Patterns of patient companionship were found to strongly correlate with specific patient sociodemographic and clinical characteristics. Interpretation of these findings helped to clarify both prevailing attitudes toward the mentally ill and the social response and management of mental illness. This article presents the study setting, methods, patient sociodemographic and clinical characteristics, and characteristics of patient companions. The second article in this series examines the statistical associations of companion number, gender and kinship relationship with patient sociodemographic and clinical characteristics.


Assuntos
Atitude/etnologia , Cultura , Transtornos Mentais/etnologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Etnopsicologia , Feminino , Humanos , Relações Interpessoais , Masculino , Transtornos Mentais/psicologia , Pessoa de Meia-Idade , Senegal/epidemiologia
13.
Soc Sci Med ; 42(3): 339-52, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8658229

RESUMO

Patient records from the Thiaroye Psychiatric Hospital in Senegal were studied to see if analysis of patterns of persons accompanying patients to the hospital could help to portray the community's response to mental illness. A systematic sample of 935 records of initial out-patients visits were examined. Patterns of patient companionship were found to strongly correlate with specific patient sociodemographic and clinical characteristics. Interpretation of these findings helped to clarify both prevailing attitudes toward the mentally ill and the social response and management of mental illness. The first article in this series presented the study setting, methods, sociodemographic and clinical characteristics of the patients, and characteristics of patient companions. The current article examines the statistical associations of companion number, gender and kinship relationship with patient sociodemographic and clinical characteristics.


Assuntos
Atitude/etnologia , Cultura , Transtornos Mentais/etnologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Família , Feminino , Humanos , Relações Interpessoais , Masculino , Pessoa de Meia-Idade , Senegal/epidemiologia
15.
Afr J Med Med Sci ; 11(3): 95-103, 1982 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6307031

RESUMO

A study was carried out in a rural area of Senegal to ascertain the pattern of mental disorders among patients presenting at primary health facilities. Among 545 children aged 5-15 years, attending health centres and posts, 17% were found to be suffering from some form of emotional problem, behaviour disturbance or neuro-psychiatric disorders. Using a 10-item screening questionnaire, it was shown that the symptoms "never plays with others' and "speech disturbance' were the strongest predictors of mental disorder among children. Among 933 adults, it was found that 16% reported more than seven symptoms commonly associated with psychiatric illness on a 24-item self-reporting questionnaire. The order in adults does not allow a precise estimate of morbidity to be made. Health workers diagnosed 9% of the patients as suffering from a mental health problem, usually in association with a physical problem. It was found that psychotic and suicidal symptoms (e.g. hallucinations, delusions) were more likely to be recognized by health workers as diagnostic of mental disorder, whereas psychophysiological symptoms (e.g. anorexia, insomnia, headache) and psychological symptoms (e.g. anxiety, depression) were less frequently recognized. The study supports the view that psychological symptoms and mental disorders occur relatively frequently among adults and children attending primary health facilities. Data allowing insight into the diagnostic sensitivity of primary health workers can provide a rational basis for planning training programmes in mental health.


Assuntos
Transtornos Mentais/diagnóstico , Adolescente , Adulto , Criança , Humanos , Transtornos Mentais/epidemiologia , Atenção Primária à Saúde , Transtornos Psicofisiológicos/diagnóstico , Transtornos Psicofisiológicos/epidemiologia , Transtornos Psicóticos/diagnóstico , Transtornos Psicóticos/epidemiologia , População Rural , Senegal , Inquéritos e Questionários
18.
Acta Neurol Belg ; 79(2): 73-91, 1979.
Artigo em Francês | MEDLINE | ID: mdl-484202

RESUMO

The authors analyze 99 well-described cases of bismuth encephalopathy and suggest a clinical syndrome according to three stages of the disease (before, during and after the acute period) and three clinical domains (psychiatry, neurology and neuropsychology). A particular attention concerns the presence of sequellar clinical signs (mnesic functions), sometimes observed one year after interruption of bismuth ingestion.


Assuntos
Bismuto , Doenças do Sistema Nervoso/induzido quimicamente , Fatores Etários , Bismuto/efeitos adversos , Feminino , Humanos , Masculino , Memória/efeitos dos fármacos , Pessoa de Meia-Idade , Transtornos dos Movimentos/induzido quimicamente , Psicoses Induzidas por Substâncias , Fatores Sexuais
19.
Acta Neurol Belg ; 78(4): 193-206, 1978.
Artigo em Francês | MEDLINE | ID: mdl-685660

RESUMO

A case of bilateral agraphia produced by a left parietal glioma is described in a 49 year-old right-handed woman. Hypothesis of a pure agraphia, etiology and non-frontal localisation of tumor are discussed. This agraphia is associated to a right astereognosia; neither functional nor behavioral relationships are found between these two defects, and it appears that their are probably associated according to the parietal locus of lesions.


Assuntos
Agrafia/etiologia , Neoplasias Encefálicas/complicações , Glioma/complicações , Lobo Parietal , Estereognose , Feminino , Lateralidade Funcional , Humanos , Matemática , Pessoa de Meia-Idade , Transtornos da Percepção/etiologia
20.
Acta Neurol Belg ; 77(5): 257-75, 1977.
Artigo em Francês | MEDLINE | ID: mdl-930559

RESUMO

The authors examine the function of calculation in 26 patients presenting lateral local cortical lesions. They analyse the symptomatology of acalculia in relation to the location and lateral position of the lesion, and define the influence of concomitant constructive apraxia or aphasia before proposing a method for the classification of calculating disorders.


Assuntos
Encefalopatias/diagnóstico , Matemática , Resolução de Problemas , Afasia/diagnóstico , Apraxias/diagnóstico , Encefalopatias/psicologia , Síndrome de Gerstmann/diagnóstico , Humanos , Testes Psicológicos
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