RESUMO
Fluoxetine is a selective serotonin reuptake inhibitor, commonly used for the treatment of a variety of psychopathological conditions. As such, fluoxetine may be expected to appear in clinical and forensic cases. Dermestes maculatus De Geer (Coleoptera: Dermestidae) has been recognized as a relevant component of the insect fauna associated with decomposing human and animal remains. Experiments were conducted to study the effect of fluoxetine on developing D. maculatus using two-drug administration models: a non-living animal model (pork muscle) and a living one (Sus scrofa L. pigs). We assessed the duration of immature stages and total life cycle, as well as morphological parameters (body length, cephalic width, and weight). The effect of fluoxetine was studied at an overdose concentration: In the non-living animal model the drug was mixed with macerated pork muscle (2000 mg/kg) and in the living animal model, pigs were given the drug orally (833 mg/kg). A control was used for each model. Daily observations were performed from the beginning to the end of the experiments. GC-MS was used for drug detection and quantification. There were no statistically significant differences in the duration of immature stages, life cycle, larval mortality, morphological parameters, or sex ratio, between treatment and control, regardless of the drug administration model. Given that fluoxetine had no detectable effect on the development of D. maculatus, detection of this drug in forensic situations would not compromise the accuracy of PMI estimations.
Assuntos
Besouros/efeitos dos fármacos , Besouros/crescimento & desenvolvimento , Fluoxetina/farmacologia , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Animais , Comportamento Alimentar , Entomologia Forense , Toxicologia Forense , Cromatografia Gasosa-Espectrometria de Massas , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Modelos Animais , Mudanças Depois da Morte , Pupa/efeitos dos fármacos , Pupa/crescimento & desenvolvimento , SuínosRESUMO
Dermestes maculatus DeGeer beetles feed and can leave marks on bones. This species is of medical, veterinary, and forensic importance. The aim of this work was to determine if the depressions produced on bones by these beetles could be product of pupation. We studied under controlled conditions the behavior of D. maculatus larvae maintained at 24°C ± 3°C, 52.7% average relative humidity, and a 12:12-hour light/dark cycle and fed on pig carcasses. Observations were made, and photographs were taken. The results indicated that depressions produced by D. maculatus were consequence of feeding or pupation. This is the first time that pupation chambers on bones are confirmed.
Assuntos
Osso e Ossos/patologia , Besouros/crescimento & desenvolvimento , Pupa/crescimento & desenvolvimento , Animais , Comportamento Alimentar , Entomologia Forense , Larva/crescimento & desenvolvimento , Modelos Animais , Oviposição , SuínosRESUMO
Mosquitoes (Diptera: Culicidae) are vectors of important parasites and pathogens causing death, poverty and social disability worldwide. The overuse of synthetic insecticides to control mosquito vectors lead to resistance, adverse environmental effects and high operational costs. Therefore, the development of eco-friendly control tools is an important public health challenge. In this study, two different essential oils (EO) (geranium, Geranium maculatum, and bergamot, Citrus bergamia) loaded polymeric nanoparticle (PN) were elaborated using polyethylene glycol (PEG) and chitosan (Qx) as the polymeric matrix/coating. In addition, the mosquito larvicidal acute and residual activity of the PN was evaluated on Culex pipiens pipiens. The physicochemical characterization of PN revealed that PEG-PN had sizes <255 nm and encapsulation efficiency between 68 and 77%; Qx-PN showed sizes <535 nm and encapsulation efficiency between 22 and 38%. From the toxicological test, it was observed that Qx-PN produced higher acute and residual activity than PEG-PN. Overall, this study highlights that polymer nanoparticles containing essential oil are a promising source of eco-friendly mosquito larvicidal products.
Assuntos
Controle de Mosquitos , Nanopartículas , Polímeros , Animais , Culex , Inseticidas , Larva , Óleos VoláteisRESUMO
Microemulsions (ME) are thermodynamically stable isotropic mixtures of oil, water, and surfactant; they would also be attractive as potential insecticidal products due to the high bioviability of the active ingredient, attributable to the small sizes of the oil drops. A laboratory study was conducted in order to compare the biological effect of oil in water (o/w) geranium essential oil (EO) and geraniol MEs and emulsions, against Culex pipiens pipiens mosquito larvae. The systems were based on three nonionic surfactants (Cremophor EL, Brij 35, Tween 80). The MEs showed dispersed phase diameters in the range of 8 to 14 nm and had low PDI values (<0.2). The MEs were analyzed by TEM, indicating that they had nearly spherical morphology. The microemulsified systems based on geranium EO and those of geraniol produced a notable increase of the larvicidal activity when compared with the respectably emulsions, concluding that the biological effect is related with the diameter of the dispersed phase. The smallest drops achieved the highest larvicidal activity, being the aqueous nanoformulations based on geraniol most effective than those of geranium EO. However, geranium microemulsions are preferred due to their residual toxicological profiles. The results indicate that these novel systems could be used in integrated pest management program for the C. pipiens pipiens.
Assuntos
Culex , Geranium/química , Inseticidas , Controle de Mosquitos , Óleos Voláteis , Terpenos , Monoterpenos Acíclicos , Animais , Culex/crescimento & desenvolvimento , Emulsões , Larva , Dose Letal Mediana , Tamanho da Partícula , Polietilenoglicóis , Polissorbatos , Tensoativos , ÁguaRESUMO
La araña Latrodectus mirabilis (Holmberg, 1876) se encuentra comúnmente en cultivos de cereales del centro de Argentina. Se estudió la composición de la dieta a campo y la tasa de captura sobre hormigas cortadoras negras a laboratorio. Este estudio documenta el primer registro de la dieta de L. mirabilis en cultivos de trigo y avena del centro de Argentina. Se identificaron 1004 ítem presa colectados de las telas de L. mirabilis en las últimas etapas fenológicas de ambos cultivos. La composición de presas fue variable, pero las arañas se alimentaron principalmente de hormigas (Formicidae, Hymenoptera), las cuales representaban más del 86% del total de las presas capturadas. A su vez, en las experiencias de tasa de captura, registramos una alta tasa de captura de hormigas al inicio de las mismas, capturando la mitad de las hormigas en las primeras cuatro horas. En resumen, reportamos una dieta polífaga en esta especie de araña en los cultivos de trigo y avena. El ítem presa más importante fueron las hormigas, resultados similares a los encontrados en otras especies del género Latrodectus.
The spider Latrodectus mirabilis (Holmberg, 1876) is commonly found in cereals crops of central Argentina. We studied its diet composition at the field and capture rate on leaf-cutting ants based on laboratory experiments. This study comprises the first approach that documents the diet of L. mirabilis in wheat and oat fields of central Argentina. We identified 1,004 prey items collected from its webs during the last phenological stages of both cereal crops. The prey composition was variable but the spiders prey mainly on ants (Formicidae, Hymenoptera), who represented more than 86% of the total. Meanwhile, in the capture rate experiences we registered a high proportion of ants captured by spiders at the beginning of experiences, capturing the half of the ants from total in the first four hours. Summarizing, we reported a polyphagous diet of this spider species in wheat and oat fields. Ants were the most important prey item of this spider, as found in other Latrodectus spiders around the world.
Assuntos
Animais , Aranhas/fisiologia , Aranhas/metabolismo , Cadeia Alimentar , Dieta/métodosRESUMO
La araña Latrodectus mirabilis (Holmberg, 1876) se encuentra comúnmente en cultivos de cereales del centro de Argentina. Se estudió la composición de la dieta a campo y la tasa de captura sobre hormigas cortadoras negras a laboratorio. Este estudio documenta el primer registro de la dieta de L. mirabilis en cultivos de trigo y avena del centro de Argentina. Se identificaron 1004 ítem presa colectados de las telas de L. mirabilis en las últimas etapas fenológicas de ambos cultivos. La composición de presas fue variable, pero las arañas se alimentaron principalmente de hormigas (Formicidae, Hymenoptera), las cuales representaban más del 86% del total de las presas capturadas. A su vez, en las experiencias de tasa de captura, registramos una alta tasa de captura de hormigas al inicio de las mismas, capturando la mitad de las hormigas en las primeras cuatro horas. En resumen, reportamos una dieta polífaga en esta especie de araña en los cultivos de trigo y avena. El ítem presa más importante fueron las hormigas, resultados similares a los encontrados en otras especies del género Latrodectus.(AU)
The spider Latrodectus mirabilis (Holmberg, 1876) is commonly found in cereals crops of central Argentina. We studied its diet composition at the field and capture rate on leaf-cutting ants based on laboratory experiments. This study comprises the first approach that documents the diet of L. mirabilis in wheat and oat fields of central Argentina. We identified 1,004 prey items collected from its webs during the last phenological stages of both cereal crops. The prey composition was variable but the spiders prey mainly on ants (Formicidae, Hymenoptera), who represented more than 86% of the total. Meanwhile, in the capture rate experiences we registered a high proportion of ants captured by spiders at the beginning of experiences, capturing the half of the ants from total in the first four hours. Summarizing, we reported a polyphagous diet of this spider species in wheat and oat fields. Ants were the most important prey item of this spider, as found in other Latrodectus spiders around the world.(AU)
Assuntos
Animais , Aranhas/metabolismo , Aranhas/fisiologia , Dieta/métodos , Cadeia AlimentarRESUMO
The essential oils from leaves of Schinus molle var. areira, Aloysia citriodora, Origanum vulgare and Thymus vulgaris have showed potential as phytoinsecticides against the green stink bug, Nezara viridula. In this work were evaluated their toxicological and behavioral effects on the parasitoid Trissolcus basalis, a biological control agent of this pest insect. Essential oils were obtained via hydrodestillation from fresh leaves. Insecticide activity in T. basalis females was evaluated in direct contact and fumigation bioassays. Behavioral effects were evaluated in olfactometer bioassays. To evaluate the residual toxicity, females of the parasitoids were exposed to oil residues; in these insects, the sublethal effects were evaluated (potential parasitism and survivorship of immature stages). The essential oils from O. vulgare and T. vulgaris proved to be highly selective when used as fumigant and did not change parasitoid behavior. After one week, the residues of these oils were harmless and did not show sublethal effects against T. basalis. According with these results, essential oils have potential applications for the integrated management of N. viridula.
Assuntos
Produtos Agrícolas/parasitologia , Hemípteros/parasitologia , Himenópteros/efeitos dos fármacos , Inseticidas/toxicidade , Óleos Voláteis/toxicidade , Óleos de Plantas/toxicidade , Animais , Ovos/parasitologia , Feminino , Inseticidas/isolamento & purificação , Óleos Voláteis/isolamento & purificação , Origanum/química , Controle Biológico de Vetores , Óleos de Plantas/isolamento & purificação , Thymus (Planta)/químicaRESUMO
The human head louse, Pediculus humanus capitis De Geer (Anoplura: Pediculidae), is a worldwide public health concern. This human obligate ectoparasite usually infests school age children. The aim of this work was to investigate the prevalence of head lice in kindergarten children from Bahia Blanca. In addition, the influence of risk factors for pediculosis infestation, such as gender, hair characteristics, and socioeconomic class, was studied in relation to the prevalence of this ectoparasite. From a total of 220 pupils examined (125 girls and 95 boys), 94 showed pediculosis. The overall prevalence of head lice infestation was 42.7 %. Pediculosis was more frequent in girls (53.6 %) than in boys (28.4 %) and in medium, long, and very long hairs. No differences were found between socioeconomic classes. This indicated that head lice are relatively common in kindergarten children from Bahía Blanca.
Assuntos
Infestações por Piolhos/epidemiologia , Infestações por Piolhos/parasitologia , Pediculus , Animais , Argentina/epidemiologia , Criança , Feminino , Cabelo , Humanos , Masculino , Prevalência , Caracteres SexuaisRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Schinus molle var. areira L. (Anacardiaceae) is employed in herbal medicine for many conditions, including respiratory, urinary and menstrual disorders, and as a digestive stimulant, diuretic, astringent and antidepressant. It is also known for its topical use as wound healer, antiseptic, for skin disorders and as repellent and insecticide. In the present work, the acute dermal exposure to ethanolic and hexanic extracts from leaves of Schinus molle var. areira was studied in rats. MATERIALS AND METHODS: A single dose of 2000 mg/kg of body weight of ethanolic and hexanic extracts from leaves was applied on the shaved skin of male and female rats. After 24h of exposure, the patch was removed and any sign of irritation was recorded. Behavioral and functional parameters in a functional observational battery and motor activity in an open field were assessed after the exposure to the extracts. Then, after 14 days of observation, animals were retested. Finally, histopathological studies were conducted on several organs. RESULTS: Slight signs of erythema and edema were observed in the skin site of exposure, but they disappeared after 48 h. The exposure to the hexanic extract produced an increase in parameters of activity, rearing and arousal assessed in the functional observational battery, which reversed after 14 days. On the other hand, the ethanolic extract caused an increase in locomotor activity, reflected in a higher number of rearings performed in the open field in the evaluation carried out on Day 14. No histopathological alterations were detected in the analyzed organs. CONCLUSIONS: The results show that the acute dermal exposure of the ethanolic and hexanic extracts from leaves of Schinus molle var. areira only causes a slight and reversible skin irritation, and a mild stimulatory effect in rats. All these indicate that the topical use of these extracts would be safe.
Assuntos
Anacardiaceae , Etanol/química , Hexanos/química , Extratos Vegetais/farmacologia , Pele/efeitos dos fármacos , Solventes/química , Administração Cutânea , Anacardiaceae/química , Animais , Comportamento Animal/efeitos dos fármacos , Edema/induzido quimicamente , Eritema/induzido quimicamente , Feminino , Masculino , Atividade Motora/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade , Folhas de Planta , Plantas Medicinais , Ratos , Ratos Wistar , Pele/patologia , Fatores de TempoRESUMO
Essential oils extracted from leaves and fruits of Schinus areira (Anacardiaceae) were tested for their repellent, toxic and feeding deterrent properties against Tribolium castaneum (Coleoptera: Tenebrionidae) larvae and adults. A topical application assay was employed for the contact toxicity study and filter paper impregnation for the fumigant assay. A treated diet was also used to evaluate the repellent activity and a flour disk bioassay for the feeding deterrent action and nutritional index alteration. The essential oil of the leaves contained mainly monoterpenoids, with alpha-phellandrene, 3-carene and camphene predominant, whereas that from the fruits contained mainly alpha-phellandrene, 3-carene and beta-myrcene. The leaf essential oil showed repellent effects, whereas that from the fruit was an attractant. Both oils produced mortality against larvae in topical and fumigant bioassays, but fumigant toxicity was not found against adults. Moreover, both essential oils produced some alterations in nutritional index. These results show that the essential oils from S. areira could be applicable to the management of populations of Tribolium castaneum.