According to the World Health Organization vector-borne diseases account for more than 17% of all infectious diseases, causing more than 700,000 deaths annually. Vectors are organisms that are able to transmit infectious pathogens between humans, or from animals to humans. Many of these vectors are hematophagous insects, which ingest the pathogen from an infected host during a blood meal, and later transmit it into a new host.
View Article and Find Full Text PDFPlant and herbal essential oils (EOs) offer a wide range of pharmacological actions that include anticancer effects. Here, we evaluated the cytotoxic activity of EO from (chemotype linalool), (chemotype dihydrocarvone, LaDEO), (L.) (CnEO), , × , × , L.
View Article and Find Full Text PDFEntomopathogenic fungi such as are extensively used for the control of insect pests worldwide. They infect mostly by adhesion to the insect surface and penetration through the cuticle. However, some insects, such as the red flour beetle (Herbst), have evolved resistance by embedding their cuticle with antifungal compounds.
View Article and Find Full Text PDFThe Triatoma sordida subcomplex traditionally included four triatomine species, T. sordida, Triatoma garciabesi, Triatoma guasayana, and Triatoma patagonica, distributed in the Southern Cone of South America. These species have a large intraspecific variability together with an overall similarity, making difficult to establish their taxonomic status.
View Article and Find Full Text PDFPest Manag Sci
November 2021
Background: The redbanded stink bug Piezodorus guildinii (Heteroptera: Pentatomidae) is one of the most important species affecting soybean crops in southern South America. Capillary gas chromatography coupled to mass spectrometry was used to characterize the epicuticular hydrocarbon profiles of field-collected insects, and to identify differences in their composition between fifth-instar nymphs and adults, males and females, and between bugs collected in insecticide-treated and insecticide-free soybean crops.
Results: Straight chain saturated n-C27 and n-C29, and monomethyl and dimethyl chains of C31 and C33 were the most abundant compounds.
Malaria incidence has halved since the year 2000, with 80% of the reduction attributable to the use of insecticides. However, insecticide resistance is now widespread, is rapidly increasing in spectrum and intensity across Africa, and may be contributing to the increase of malaria incidence in 2018. The role of detoxification enzymes and target site mutations has been documented in the major malaria vector Anopheles gambiae; however, the emergence of striking resistant phenotypes suggests the occurrence of additional mechanisms.
View Article and Find Full Text PDFSeveral filamentous fungi are able to concomitantly assimilate both aliphatic and polycyclic aromatic hydrocarbons that are the biogenic by-products of some industrial processes. Cytochrome P450 monooxygenases catalyze the first oxidation reaction for both types of substrate. Among the cytochrome P450 (CYP) genes, the family CYP52 is implicated in the first hydroxylation step in alkane-assimilation processes, while genes belonging to the family CYP53 have been linked with oxidation of aromatic hydrocarbons.
View Article and Find Full Text PDFBackground: Current Chagas disease vector control strategies, based on chemical insecticide spraying, are growingly threatened by the emergence of pyrethroid-resistant Triatoma infestans populations in the Gran Chaco region of South America.
Methodology And Findings: We have already shown that the entomopathogenic fungus Beauveria bassiana has the ability to breach the insect cuticle and is effective both against pyrethroid-susceptible and pyrethroid-resistant T. infestans, in laboratory as well as field assays.
The effects of the essential oil of mandarin peel (Corrientes, Argentina) and limonene (its major component) were studied on two human tumour cell lines growth (lung adenocarcinoma A549 and hepatocarcinoma HepG2). The essential oil was obtained by cold press and its composition was investigated by gas chromatography (GC) and GC/mass spectrometry (MS) analysis. The antiproliferative effect was studied using an MTT assay.
View Article and Find Full Text PDFEthnopharmacological Relevance: Ulomoides dermestoides (Fairmaire, 1893) is a cosmopolitan tenebrionid beetle reared by Argentine people who consume them alive as an alternative medicine in the treatment of different illnesses such as asthma, Parkinson's, diabetes, arthritis, HIV and specially cancer.
Aim Of The Study: To evaluate the cytotoxicity and DNA damage of the major volatile components released by Ulomoides dermestoides on human lung carcinoma epithelial cell line A549.
Materials And Methods: The defence compounds of Ulomoides dermestoides were extracted with dichloromethane and analyzed and quantified by capillary gas chromatography.
Triatoma dimidiata Latreille is a major vector of Chagas disease with an extensive geographic distribution from Central Mexico, through Central America, to northern South America. As a result of its variability in phenetic and genetic characters, disagreement concerning its taxonomic status has been raised. In this study, the cuticular hydrocarbon pattern of T.
View Article and Find Full Text PDFComp Biochem Physiol B Biochem Mol Biol
December 2009
Many species of tenebrionids produce and secrete a defensive volatile blend containing mainly benzoquinones and alkenes. In this study we characterized the volatile organic compounds (VOC) of the beetle Ulomoides dermestoides (Coleoptera: Tenebrionidae). Solid phase microextraction (SPME) coupled to capillary gas chromatography-mass spectrometry (CGC-MS) analysis was used to identify methyl-1,4-benzoquinone (MBQ), ethyl-1,4-benzoquinone (EBQ), 1-tridecene (C(13:1)), and 1-pentadecene (C(15:1)), representing more than 90% of the volatile blend.
View Article and Find Full Text PDFBackground: Triatoma infestans-mediated transmission of Tripanosoma cruzi, the causative agent of Chagas disease, remains as a major health issue in southern South America. Key factors of T. infestans prevalence in specific areas of the geographic Gran Chaco region-which extends through northern Argentina, Bolivia, and Paraguay-are both recurrent reinfestations after insecticide spraying and emerging pyrethroid-resistance over the past ten years.
View Article and Find Full Text PDFBackground: The triatomine bugs are vectors of the protozoan parasite Trypanosoma cruzi, the causative agent of Chagas disease. Aggregation behavior plays an important role in their survival by facilitating the location of refuges and cohesion of aggregates, helping to keep them safely assembled into shelters during daylight time, when they are vulnerable to predators. There are evidences that aggregation is mediated by thigmotaxis, by volatile cues from their faeces, and by hexane-extractable contact chemoreceptive signals from their cuticle surface.
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