RESUMEN
Women need multipurpose prevention technologies (MPTs) to simultaneously prevent sexually transmitted infections (STIs), including HIV, with or without contraception. User feedback early in product development is critical for maximizing uptake and continuation. Our global online survey (April 2017-December 2018) explored women's opinions about MPT formulations in development (e.g., fast-dissolving vaginal inserts, vaginal films, intravaginal rings, injectables, implants), preferences for long-acting or "on-demand" methods, and interest in a contraceptive MPT versus products for HIV/STI prevention alone. Of the 630 women in our final analysis (mean 30 years old; range 18-49), 68% were monogamous, 79% completed secondary education, 58% had ≥ 1 child, 56% were from sub-Saharan Africa and 82% preferred a cMPT versus HIV/STI prevention alone. There were no clear preferences for any specific product or product type (long-acting, on-demand, daily). No single product will appeal everyone, however, adding contraception is likely to increase uptake of HIV/STI prevention methods for most women.
RESUMEN: Las mujeres necesitan tecnologías de prevención multipropósito (TPM) para prevenir simultáneamente las infecciones de transmisión sexual (ITS), incluido el VIH, con o sin anticoncepción. Las opiniones de los usuarios cuando un producto comienza a desarrollarse son fundamentales para maximizar la adopción y continuación de dicho producto. Nuestra encuesta global realizada en internet (abril de 2017diciembre de 2018) exploró las opiniones de las mujeres sobre diferentes fórmulas o dispositivos de TPM que se están desarrollando (ej., insertos vaginales de disolución rápida, láminas vaginales, anillos intravaginales, inyectables, implantes). En esta encuesta se indagó acerca de las preferencias en términos de período de acción (prolongado o breve) y propósito del uso (anticonceptivo, productos para la prevención del VIH/ITS, o ambos). De las 630 mujeres (media de 30 años; rango 1849) en el análisis final, el 68% eran monógamas, el 79% completaron la educación secundaria, el 58% tenían ≥ 1 hijo, el 56% eran del África subsahariana y el 82% preferían una TPM con componente anticonceptivo en vez de un producto para la prevención de VIH/ITS exclusivamente. No hubo preferencias claras por ningún producto o tipo de producto específico (de acción prolongada, de acción breve, de uso diario). Ningún producto por sí solo logró abarcar todas las preferencias; sin embargo, es probable que la inclusión de métodos anticonceptivos en una TPM aumente el uso de métodos de prevención del VIH/ITS en la mayoría de las mujeres.
Asunto(s)
Infecciones por VIH , Enfermedades de Transmisión Sexual , Adulto , Femenino , Humanos , Anticoncepción/métodos , Anticonceptivos , Dispositivos Anticonceptivos , Infecciones por VIH/prevención & control , Enfermedades de Transmisión Sexual/prevención & control , Adolescente , Adulto Joven , Persona de Mediana EdadRESUMEN
The idea that increased levels of extraversion are beneficial to well-being is widespread. Drawing on the idea that behaving discordant to one's trait level is demanding and effortful to maintain, and that repeated taxations of one's self-regulatory resources are unpleasant, we examined the relationship between cumulative counterdispositional extraversion and positive feelings. In two experience-sampling (ESM) studies, participants repeatedly rated their level of state extraversion and positive feelings. Results revealed that cumulative positive deviations from one's trait extraversion level were positively associated with positive feelings, whereas cumulative negative deviations were negatively associated with positive feelings. This confirms the idea that, also when looking at cumulative instances of extraversion-related behaviors, higher levels of extraversion go hand in hand with higher levels of positive feelings.
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Extraversión Psicológica , Conducta Social , Afecto , Emociones , Humanos , PersonalidadRESUMEN
Bed bugs are pests of public health importance due to their relentless biting habits that can lead to allergies, secondary infections and mental health issues. When not feeding on human blood bed bugs aggregate in refuges close to human hosts. This aggregation behaviour could be exploited to lure bed bugs into traps for surveillance, treatment efficacy monitoring and mass trapping efforts, if the responsible cues are identified. The aim of this study was to identify and quantify the bed bug aggregation pheromone. Volatile chemicals were collected from bed bug-exposed papers, which are known to induce aggregation behaviour, by air entrainment. This extract was tested for behavioural and electrophysiological activity using a still-air olfactometer and electroantennography, respectively. Coupled gas chromatography-electroantennography (GC-EAG) was used to screen the extract and the GC-EAG-active chemicals, benzaldehyde, hexanal, (E)-2-octenal, octanal, nonanal, decanal, heptanal, (R,S)-1-octen-3-ol, 3-carene, ß-phellandrene, (3E,5E)-octadien-2-one, (E)-2-nonenal, 2-decanone, dodecane, nonanoic acid, 2-(2-butoxyethoxy)ethyl acetate, (E)-2-undecanal and (S)-germacrene D, were identified by GC-mass spectrometry and quantified by GC. Synthetic blends, comprising 6, 16, and 18 compounds, at natural ratios, were then tested in the still-air olfactometer to determine behavioural activity. These aggregation chemicals can be manufactured into a lure that could be used to improve bed bug management.
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Chinches/fisiología , Olfatometría/instrumentación , Feromonas/análisis , Animales , Antenas de Artrópodos/fisiología , Chinches/química , Conducta Animal , Cromatografía de Gases , Fenómenos Electrofisiológicos , Control de Insectos , Espectrometría de Masas , Feromonas/químicaRESUMEN
Mosquitoes infected with malaria parasites have demonstrated altered behaviour that may increase the probability of parasite transmission. Here, we examine the responses of the olfactory system in Plasmodium falciparum infected Anopheles gambiae, Plasmodium berghei infected Anopheles stephensi, and P. berghei infected An. gambiae. Infected and uninfected mosquitoes showed differential responses to compounds in human odour using electroantennography coupled with gas chromatography (GC-EAG), with 16 peaks triggering responses only in malaria-infected mosquitoes (at oocyst, sporozoite or both stages). A selection of key compounds were examined with EAG, and responses showed differences in the detection thresholds of infected and uninfected mosquitoes to compounds including lactic acid, tetradecanoic acid and benzothiazole, suggesting that the changes in sensitivity may be the reason for differential attraction and biting at the oocyst and sporozoite stages. Importantly, the different cross-species comparisons showed varying sensitivities to compounds, with P. falciparum infected An. gambiae differing from P. berghei infected An. stephensi, and P. berghei infected An. gambiae more similar to the P. berghei infected An. stephensi. These differences in sensitivity may reflect long-standing evolutionary relationships between specific Plasmodium and Anopheles species combinations. This highlights the importance of examining different species interactions in depth to fully understand the impact of malaria infection on mosquito olfactory behaviour.
Asunto(s)
Anopheles/fisiología , Anopheles/parasitología , Malaria/transmisión , Animales , Anopheles/metabolismo , Benzotiazoles/metabolismo , Cromatografía de Gases , Femenino , Ácido Láctico/metabolismo , Malaria/metabolismo , Malaria/fisiopatología , Mosquitos Vectores/metabolismo , Mosquitos Vectores/parasitología , Mosquitos Vectores/fisiología , Ácido Mirístico/metabolismoRESUMEN
Insect pests can reduce wheat yield by direct feeding and transmission of plant viruses. Here we report results from laboratory and field phenotyping studies on a wide range of wheat, including landraces from the Watkins collection deriving from before the green revolution, more modern cultivars from the Gediflux collection (north-western Europe) and modern UK Elite varieties, for resistance to the bird cherry-oat aphid, Rhopalosiphum padi (Homoptera: Aphididae) and the English grain aphid, Sitobion avenae (Homoptera: Aphididae). A total of 338 lines were screened for R. padi and 340 lines for S. avenae. Field trials were also conducted on 122 Watkins lines to identify wheat bulb fly, Delia coarctata, preference on these landraces. Considerable variation was shown in insect performance among and within different wheat collections, with reduced susceptibility in a number of varieties, but phenotyping did not identify strong resistance to aphids or wheat bulb fly. Field trials showed within collection differences in aphid performance, with fewer aphids populating lines from the Watkins collection. This differs from development data in laboratory bioassays and suggests that there is a pre-alighting cue deterring aphid settlement and demonstrates differences in aphid preference and performance on older plants in the field compared with seedlings in the laboratory, highlighting the need for phenotyping for aphid resistance at different plant growth stages. No association was identified between performance of the different insect species on individual varieties, potentially suggesting different nutritional requirements or resistance mechanisms.
RESUMEN
The potential for developing botanically derived natural products as novel feed-through repellents for disrupting settlement of the salmon louse, Lepeophtheirus salmonis (Caligidae) upon farmed Atlantic salmon, Salmo salar, was investigated using an established laboratory vertical Y-tube behavioural bioassay for assessing copepodid behaviour. Responses to artificial sea water conditioned with the odour of salmon, or to the known salmon-derived kairomone component, α-isophorone, in admixture with selected botanical materials previously known to interfere with invertebrate arthropod host location were recorded. Materials included oils extracted from garlic, Allium sativum (Amaryllidaceae), rosemary, Rosmarinus officinalis (Lamiaceae), lavender, Lavandula angustifolia (Lamiaceae), and bog myrtle, Myrica gale (Myricaceae), and individual components (diallyl sulphide and diallyl disulphide from garlic; allyl, propyl, butyl, 4-pentenyl and 2-phenylethyl isothiocyanate from plants in the Brassica genus). Removal of attraction to salmon-conditioned water (SCW) or α-isophorone was observed when listed materials were presented at extremely low parts per trillion (ppt), that is picograms per litre or 10-12 level. Significant masking of attraction to SCW was observed at a level of 10 ppt for diallyl disulphide and diallyl sulphide, and allyl isothiocyanate and butyl isothiocyanate. The potential of very low concentrations of masking compounds to disrupt Le. salmonis copepodid settlement on a host fish has been demonstrated in vitro.
Asunto(s)
Copépodos/efectos de los fármacos , Infestaciones Ectoparasitarias/veterinaria , Enfermedades de los Peces/tratamiento farmacológico , Conducta de Búsqueda de Hospedador/efectos de los fármacos , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Salmo salar , Animales , Antiparasitarios/farmacología , Antiparasitarios/uso terapéutico , Copépodos/fisiología , Ciclohexanonas/farmacología , Ciclohexanonas/uso terapéutico , Infestaciones Ectoparasitarias/tratamiento farmacológico , Infestaciones Ectoparasitarias/parasitología , Enfermedades de los Peces/parasitología , Isotiocianatos/farmacología , Isotiocianatos/uso terapéutico , Magnoliopsida/química , Feromonas/farmacología , Feromonas/uso terapéuticoRESUMEN
OBJECTIVE To assess the effects of topically applied 2% dorzolamide hydrochloride-0.5% timolol maleate ophthalmic solution (DHTM) on incidence and severity of postoperative ocular hypertension (POH; ie, intraocular pressure [IOP] > 25 mm Hg) in dogs undergoing cataract extraction by phacoemulsification. DESIGN Randomized, masked, controlled study. ANIMALS 103 dogs (180 eyes). PROCEDURES Pertinent history, signalment, and ophthalmic examination findings were recorded. Dogs received 1 drop of DHTM or sham treatment solution (sterile, buffered, isotonic eye drops) in both eyes 14 hours and 2 hours before anesthetic induction and at the time of corneal incision closure (ie, end of surgery); IOPs were assessed by rebound tonometry 2, 4, 6, and 8 hours after surgery and between 7:30 and 8:00 am on the following day. Dogs with IOPs of 26 to 45 mm Hg received 1 drop of 0.005% latanoprost solution topically; the surgeon's treatment of choice was used for dogs with IOPs > 45 mm Hg. Incidence of POH and postoperative IOPs were compared between treatment groups. RESULTS DHTM treatment resulted in significantly lower incidence of POH than did sham treatment at the level of the dog (18/53 [34%] vs 31/50 [62%]) and the eye (24/94 [26%] vs 42/86 [48%]). Mean IOP did not differ between groups at the time of POH detection. The DHTM-treated eyes that developed POH were significantly more likely to have a 1-hour follow-up IOP < 25 mm Hg after latanoprost administration than were sham-treated eyes (19/25 [76%] vs 18/35 [51%]; OR, 3.87). CONCLUSIONS AND CLINICAL RELEVANCE Multidose perioperative administration of DHTM in dogs undergoing phacoemulsification reduced the incidence of POH and improved responsiveness of POH to latanoprost treatment.
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Extracción de Catarata/veterinaria , Enfermedades de los Perros/etiología , Hipertensión Ocular/veterinaria , Complicaciones Posoperatorias/veterinaria , Sulfonamidas/farmacología , Tiofenos/farmacología , Timolol/farmacología , Animales , Antihipertensivos/administración & dosificación , Antihipertensivos/farmacología , Extracción de Catarata/efectos adversos , Enfermedades de los Perros/prevención & control , Perros , Combinación de Medicamentos , Hipertensión Ocular/prevención & control , Atención Perioperativa , Complicaciones Posoperatorias/prevención & control , Sulfonamidas/administración & dosificación , Tiofenos/administración & dosificación , Timolol/administración & dosificaciónRESUMEN
Previous studies have shown that the boll weevil, Anthonomus grandis, is attracted to constitutive and conspecific herbivore-induced cotton volatiles, preferring the blend emitted by cotton at the reproductive over the vegetative stage. Moreover, this preference was paralleled by the release of the acyclic homoterpenes (tetranorterpenes) (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT) and (E,E)-4,8,12-trimethyltrideca-1,3,7,11-tetraene (TMTT) in Delta Opal cotton being higher at the vegetative than at the reproductive stage. Here, we evaluated whether this difference in release of acyclic homoterpenes also occurred in other cotton varieties, and if boll weevils could recognize these compounds as indicators of a specific cotton phenological stage. Results showed that cotton genotypes CNPA TB-90, BRS-293 and Delta Opal all produced higher levels of DMNT and TMTT at the vegetative stage than at the reproductive stage and that these homoterpenes allowed for principal component analysis separation of volatiles produced by the two phenological stages. Electroantennograms confirmed boll weevil antennal responses to DMNT and TMTT. Behavioral assays, using Y-tube olfactometers, showed that adding synthetic homoterpenes to reproductive cotton volatiles (mimicking cotton at the vegetative stage in terms of homoterpene levels) resulted in reduced attraction to boll weevils compared to that to unmodified reproductive cotton. Weevils showed no preference when given a choice between plants at the vegetative stage and the vegetative stage-mimicked plant. Altogether, the results show that DMNT and TMTT are used by boll weevils to distinguish between cotton phenological stages.
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Conducta Animal/efectos de los fármacos , Terpenos/química , Terpenos/farmacología , Gorgojos/efectos de los fármacos , Animales , Bioensayo , Femenino , Genotipo , Gossypium/genética , Gossypium/metabolismo , Masculino , Terpenos/metabolismoRESUMEN
The rice C-glycosyltransferase (OsCGT) is one of only a small number of characterised plant C-glycosyltransferases (CGT) known. The enzyme C-glucosylates a 2-hydroxyflavanone substrate with UDP-glucose as the sugar donor to produce C-glucosyl-2-hydroxyflavanones. We tested substrate specificity of the enzyme, using synthetic 2-hydroxyflavanones, and showed it has the potential to generate known natural CGFs that have been isolated from rice and also other plants. In addition, we synthesised novel, unnatural 2-hydroxyflavanone substrates to test the B-ring chemical space of substrate accepted by the OsCGT and demonstrated the OsCGT capacity as a synthetic reagent to generate significant quantities of known and novel CGFs. Many B-ring analogues are tolerated within a confined steric limit. Finally the OsCGT was used to generate novel mono-C-glucosyl-2-hydroxyflavanones as putative biosynthetic intermediates to examine the potential of Desmodium incanum biosynthetic CGTs to produce novel di-C-glycosylflavones, compounds implicated in the allelopathic biological activity of Desmodium against parasitic weeds from the Striga genus.
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Flavonas/metabolismo , Glicósidos/metabolismo , Glicosiltransferasas/metabolismo , Oryza , Raíces de Plantas/metabolismo , Flavonas/química , Glicósidos/química , Estructura Molecular , Oryza/química , Oryza/enzimología , Oryza/genéticaRESUMEN
Molecular imaging provides considerable insight into biological processes for greater understanding of health and disease. Numerous advances in medical physics, chemistry and biology have driven the growth of this field in the past two decades. With exquisite sensitivity, depth of detection and potential for theranostics, radioactive imaging approaches have played a major role in the emergence of molecular imaging. At the same time, developments in materials science, characterization and synthesis have led to explosive progress in the nanoparticle (NP) sciences. NPs are generally defined as particles with a diameter in the nanometre size range. Unique physical, chemical and biological properties arise at this scale, stimulating interest for applications as diverse as energy production and storage, chemical catalysis and electronics. In biomedicine, NPs have generated perhaps the greatest attention. These materials directly interface with life at the subcellular scale of nucleic acids, membranes and proteins. In this review, we will detail the advances made in combining radioactive imaging and NPs. First, we provide an overview of the NP platforms and their properties. This is followed by a look at methods for radiolabelling NPs with gamma-emitting radionuclides for use in single photon emission CT and planar scintigraphy. Next, utilization of positron-emitting radionuclides for positron emission tomography is considered. Finally, recent advances for multimodal nuclear imaging with NPs and efforts for clinical translation and ongoing trials are discussed.
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Imagen Molecular/métodos , Nanopartículas , Radioquímica/métodos , Radioisótopos , Humanos , Tomografía de Emisión de Positrones , Tomografía Computarizada de Emisión de Fotón ÚnicoRESUMEN
Plants from the genus Desmodium, in particular D. uncinatum, are used on sub-Saharan small-holder farms as intercrops to inhibit parasitism of cereal crops by Striga hermonthica and Striga asiatica via an allelopathic mechanism. The search for Desmodium species which are adapted to more arid conditions, and which show resilience to increased drought stress, previously identified D. intortum, D. incanum and D. ramosissimum as potential drought tolerant intercrops. Their potential as intercrops was assessed for resource poor areas of rain-fed cereal production where drought conditions can persist through normal meteorological activity, or where drought may have increasing impact through climate change. The chemical composition of the root exudates were characterised and the whole exudate biological activity was shown to be active in pot experiments for inhibition of Striga parasitism on maize. Furthermore, rain fed plot experiments showed the drought tolerant Desmodium intercrops to be effective for Striga inhibition. This work demonstrates the allelopathic nature of the new drought tolerant intercrops through activity of root exudates and the major compounds seen in the exudates are characterised as being C-glycosylflavonoid. In young plants, the exudates show large qualitative differences but as the plants mature, there is a high degree of convergence of the C-glycosylflavonoid exudate chemical profile amongst active Desmodium intercrops that confers biological activity. This defines the material for examining the mechanism for Striga inhibition.
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Exudados y Transudados/química , Feromonas/química , Raíces de Plantas/química , Striga/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Productos Agrícolas , Sequías , Fabaceae/química , Flavonoides/análisis , Flavonoides/química , Flavonoides/aislamiento & purificación , Espectrometría de Masas/métodos , Feromonas/aislamiento & purificación , Feromonas/farmacologíaRESUMEN
The Mediterranean fruit fly (or medfly), Ceratitis capitata (Wiedemann; Diptera: Tephritidae), is a serious pest of agriculture worldwide, displaying a very wide larval host range with more than 250 different species of fruit and vegetables. Olfaction plays a key role in the invasive potential of this species. Unfortunately, the pheromone communication system of the medfly is complex and still not well established. In this study, we report the isolation of chemicals emitted by sexually mature individuals during the "calling" period and the electrophysiological responses that these compounds elicit on the antennae of male and female flies. Fifteen compounds with electrophysiological activity were isolated and identified in male emissions by gas chromatography coupled to electroantennography (GC-EAG). Within the group of 15 identified compounds, 11 elicited a response in antennae of both sexes, whilst 4 elicited a response only in female antennae. The binding affinity of these compounds, plus 4 additional compounds known to be behaviourally active from other studies, was measured using C. capitata OBP, CcapOBP83a-2. This OBP has a high homology to Drosophila melanogaster OBPs OS-E and OS-F, which are associated with trichoid sensilla and co-expressed with the well-studied Drosophila pheromone binding protein LUSH. The results provide evidence of involvement of CcapOBP83a-2 in the medfly's odorant perception and its wider specificity for (E,E)-α-farnesene, one of the five major compounds in medfly male pheromone emission. This represents the first step in the clarification of the C. capitata and pheromone reception pathway, and a starting point for further studies aimed towards the creation of new powerful attractants or repellents applicable in the actual control strategies.
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Ceratitis capitata/fisiología , Feromonas/fisiología , Receptores Odorantes/fisiología , Secuencia de Aminoácidos , Animales , Antenas de Artrópodos , Ceratitis capitata/metabolismo , Fenómenos Electrofisiológicos , Femenino , Masculino , Feromonas/aislamiento & purificación , Filogenia , Factores Sexuales , Olfato/fisiologíaRESUMEN
Hydroxamic acids (HAs) are plant secondary metabolites produced by certain cereals, which have been found to be toxic to pest aphids in artificial diet assays. Previous studies have shown that tetraploid and hexaploid wheat varieties, the leaf tissues of which contained higher levels of these compounds than used in artificial diets, did not reduce aphid settling or fecundity. This current study reports findings on a high HA producing B genome accession of the diploid ancestor of wheat, Aegilops speltoides. We found that this accession does have a negative impact on aphid host selection and substantially reduces nymph production. Whole leaf tissue assays showed very high levels of HAs, well in excess of the toxic level determined in the artificial diet assays. Extraction of the apoplast fluid (AF) from this accession showed that the HA level is much lower than that of the whole tissue, but is still close to the artificial diet toxic level. Furthermore the HA level in the AF increases in response to aphid feeding. These observations could explain why hexaploid wheat remains susceptible to aphids, despite having whole leaf tissue HA levels in excess of the toxic levels determined in artificial diets.
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Áfidos/fisiología , Herbivoria , Ácidos Hidroxámicos/metabolismo , Triticum/metabolismo , Animales , Antibiosis , Diploidia , Fertilidad , Hojas de la Planta/metabolismo , Poliploidía , Triticum/genéticaRESUMEN
This work presents the first identification of putative odorant-binding proteins (OBPs) from a member of the Pentatomidae, i.e. the brown stink bug Euschistus heros (Fabricius), an important pest of soybean in Brazil. Antennae from both sexes of E. heros adults (12 days old and unmated) were used to construct a cDNA library, from which two transcripts encoding putative E. heros OBPs (EherOBPs) were identified. The expression levels of EherOBP1 and EherOBP2 were found to be higher in male antennae than in female and there was difference in expression in legs, wings, and abdomens of the two sexes. The histolocalization of EherOBP1 and EherOBP2 transcripts in antennae also showed a sexual dimorphism in the chemoreception system, with different expression sites in the antennal segments between males and females, occurring predominantly at the base of the sensillum. The implications of these findings for stink bug chemoreception are discussed.
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Heterópteros/química , Receptores Odorantes/análisis , Animales , Brasil , Femenino , Masculino , Receptores Odorantes/metabolismo , Glycine maxRESUMEN
"Push-Pull" is an inexpensive and eminently practical strategy designed for developing countries in order to exploit sound principles of chemical ecology for agricultural pest management. This strategy is specifically suitable for small holder farmers. Their experience can easily be integrated into existing farming practices in their immediate environment. "Push-pull" within one and a half decades became widely established and meanwhile is greatly beneficial to practitioners in East Africa, mainly Kenya. The classical push-pull approach used for applied plant-insect management was pioneered by Khan and Pickett (2000) and subsequent papers of Pickett (2003) and Khan et al. (2006, 2008). Relevant plant species explored so far were maize or sorghum intercropped with other East African plants (Desmodium spp. resp. Melinis minutiflora) possessing natural chemicals repellent resp. attractive for stem borer moths Chilo partellus (Lepidoptera), whereby Desmodium spp. was grown inside the maize rows while M. minutiflora surrounded it. Both simultaneous actions combined resulted in a significant decrease of stem borers in the area to be protected. A benefit to cost ratio of 2.5 was realized. Within a period of 15 years the number of subscribing farmers substantially increased from a few dozen to more than 80,000 in 2014. Two experiments along the paths of chemical ecology were undertaken between Sept 2012 and Feb 2013: One was designed to investigate if the legume D. intortum known to produce repellent volatiles against stem borer moths induces defence in Zea mays varieties. We looked at two open-pollinated farmers' varieties and two commercial hybrid varieties suspecting the farmers' varieties to be responsive rather than the hybrids. However, no defence induction was detected in this study so far. This could be explained by an insufficient production of defence inducing volatiles in leaves of D. intortum whereas flowers might produce a sufficient response. More detailed study is needed. A second approach made use of species-specific insect monitoring traps baited with highly specific female sex pheromones for attracting and monitoring destructive insect pests. The female sex pheromone (8-methyl-decane-2-ol propanoate) of Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae) (Western Corn Rootworm) is readily available as bait in the "Metcalf sticky cup trap" for trapping males, an extraordinarily sensitive technique for monitoring the presence or absence of male beetles in a given area. Li et al. (2006) had argued for the likelihood of easy immigration of this cosmopolitan maize pest into East Africa. Our results, however, so far indicate the absence of a local population in the area of Mbita, while not excluding its presence at Nairobi or Mombasa. Both investigations contribute to different aspects of Kenyan economic development and may be seen as two independent but complementary contributions towards livelihood improvement of small holder farmers in Kenya.
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Agricultura/métodos , Control de Insectos/métodos , Control Biológico de Vectores/métodos , Enfermedades de las Plantas/prevención & control , Zea mays/crecimiento & desarrollo , Animales , Escarabajos/efectos de los fármacos , Escarabajos/fisiología , Fabaceae/química , Fabaceae/metabolismo , Femenino , Kenia , Masculino , Mariposas Nocturnas/efectos de los fármacos , Mariposas Nocturnas/fisiología , Feromonas/farmacología , Enfermedades de las Plantas/parasitología , Compuestos Orgánicos Volátiles/metabolismo , Compuestos Orgánicos Volátiles/farmacología , Zea mays/parasitologíaRESUMEN
We describe an opportunistic, disseminated infection in a German shepherd dog associated with two fungal organisms not previously reported to cause disease. Lecythophora canina, a new species here described, was isolated from an osteolytic bone lesion. A fine needle aspirate of the lesion demonstrated septate hyphae. Plectospharella cucumerina (anamorph Plectosporium tabacinum) was isolated from a urine sample. Clinical manifestations were blindness, altered mentation, and osteomyelitis. Treatment with itraconazole and terbinafine for greater than one year resulted in stable clinical disease.
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Ascomicetos/clasificación , Ascomicetos/aislamiento & purificación , Coinfección/veterinaria , Enfermedades de los Perros/microbiología , Micosis/veterinaria , Animales , Ascomicetos/genética , Biopsia con Aguja Fina , Huesos/diagnóstico por imagen , Coinfección/microbiología , ADN de Hongos/química , ADN de Hongos/genética , ADN Espaciador Ribosómico/química , ADN Espaciador Ribosómico/genética , Perros , Microscopía , Datos de Secuencia Molecular , Micosis/microbiología , Infecciones Oportunistas/microbiología , Infecciones Oportunistas/veterinaria , Osteomielitis/microbiología , Osteomielitis/veterinaria , Radiografía , Análisis de Secuencia de ADN , Orina/microbiologíaRESUMEN
The common bed bug, Cimex lectularius, feeds on the blood of mammal and bird hosts, and is a pest of global importance. Semiochemicals are chemicals involved in animal communication that may affect behaviour and/or physiology. Attractive semiochemicals that play a role in mediating bed bug behaviour could be exploited for the development of a highly effective novel monitoring device. Tracking software was used to record the response of bed bugs to volatiles from paper previously exposed to conspecific bugs in a still-air olfactometer illuminated by infrared lights, through a variety of activity variables. The effect of time of day as an extrinsic factor, and sex, stage, mating status and nutritional status as physiological factors on the response of bed bugs to the volatiles was examined. Bed bugs of both sexes and all stages responded to the volatiles from bed bug-exposed papers, showing significant attraction and orientation towards the volatile source whether they were starved or engorged. Confirmation that the physiological factors examined do not affect the response of bed bugs to the volatiles from bed bug-exposed papers provides evidence that these bed bug-derived volatiles contain aggregation cues, as semiochemicals that promote aggregation should by definition be detected by both sexes and all life stages. A device baited with such semiochemicals could play a major role in limiting the impact of the current bed bug resurgence by enabling timely detection of infestations, along with quantitative evaluation of control and effective surveillance of the geographical distribution of the pest species.
Asunto(s)
Chinches/fisiología , Feromonas/metabolismo , Comunicación Animal , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Diseño de Equipo , Humanos , Masculino , Odorantes/análisis , Conducta Sexual Animal , Olfato , VolatilizaciónRESUMEN
The boll weevil, Anthonomus grandis, has been monitored through deployment of traps baited with aggregation pheromone components. However, field studies have shown that the number of insects caught in these traps is significantly reduced during cotton squaring, suggesting that volatiles produced by plants at this phenological stage may be involved in attraction. Here, we evaluated the chemical profile of volatile organic compounds (VOCs) emitted by undamaged or damaged cotton plants at different phenological stages, under different infestation conditions, and determined the attractiveness of these VOCs to adults of A. grandis. In addition, we investigated whether or not VOCs released by cotton plants enhanced the attractiveness of the aggregation pheromone emitted by male boll weevils. Behavioral responses of A. grandis to VOCs from conspecific-damaged, heterospecific-damaged (Spodoptera frugiperda and Euschistus heros) and undamaged cotton plants, at different phenological stages, were assessed in Y-tube olfactometers. The results showed that volatiles emitted from reproductive cotton plants damaged by conspecifics were attractive to adults boll weevils, whereas volatiles induced by heterospecific herbivores were not as attractive. Additionally, addition of boll weevil-induced volatiles from reproductive cotton plants to aggregation pheromone gave increased attraction, relative to the pheromone alone. The VOC profiles of undamaged and mechanically damaged cotton plants, in both phenological stages, were not different. Chemical analysis showed that cotton plants produced qualitatively similar volatile profiles regardless of damage type, but the quantities produced differed according to the plant's phenological stage and the herbivore species. Notably, vegetative cotton plants released higher amounts of VOCs compared to reproductive plants. At both stages, the highest rate of VOC release was observed in A. grandis-damaged plants. Results show that A. grandis uses conspecific herbivore-induced volatiles in host location, and that homoterpene compounds, such as (E)-4,8-dimethylnona-1,3,7-triene and (E,E)-4,8,12-trimethyltrideca-1,3,7,11-tetraene and the monoterpene (E)-ocimene, may be involved in preference for host plants at the reproductive stage.