Exp Parasitol
May 2022
Studies on the effects of azadirachtin treatment, ecdysone supplementation and ecdysone therapy on both the ultrastructural organization of the rectum in 5th-instar nymph of Rhodnius prolixus and the ex vivo attachment behavior of Trypanosoma cruzi under these experimental conditions were carried out. Control insects had a typical and significant organization of the rectum cuticle consisted of four main layers (procuticle, inner epicuticle, outer epicuticle, and wax layer) during the entire period of the experiment. Both azadirachtin treatment and ecdysone supplementation avoid the development of both outer epicuticle and wax layer.
View Article and Find Full Text PDFSlow pyrolysis is a process for the thermochemical conversion of biomasses into bio-oils that may contain a rich chemical composition with biotechnological potential. Bio-oil produced from crambe fruits was investigated as to their acaricidal effect. Slow pyrolysis of crambe fruits was performed in a batch reactor at 400°C and chemical composition was analyzed by gas chromatography-mass spectrometry (GC-MS).
View Article and Find Full Text PDFBovine mastitis is an infectious disease that affects the mammary gland of dairy cattle with considerable economic losses. Staphylococcus aureus is the main microorganism involved in this highly contagious process, and the treatment is only using antibiotics. Currently, the search for new treatment and/or compounds is still in need due to microbial resistance.
View Article and Find Full Text PDFThe cattle tick Rhipicephalus microplus is a significant problem for livestock, causing losses of billions of dollars per year. This work aimed to determine the chemical composition of essential oils obtained from Laurus nobilis and Copaifera officinalis and evaluate activity against engorged R. microplus females.
View Article and Find Full Text PDFMRSA infection and colonization have been reported in both companion and food-chain animals, highlighting MRSA as an important veterinary and zoonotic pathogen. Another mec allele, the mecC gene, also confers beta-lactam resistance in Staphylococcus aureus and shows 69% nucleotide identity to mecA. The main aim of this study was to investigate the genotypic and clonal profile of methicillin-resistant S.
View Article and Find Full Text PDFBackground: The frequency of primary and revision total knee and hip replacements (pTKRs, rTKRs, pTHRs, and rTHRs, respectively) is increasing in the United States due to demographic changes. This study evaluated the impact of preoperative patient and clinical factors on the risk of surgical site infection (SSI) within the 90-day period after primary and revision total joint replacements (TJR).
Methods: A retrospective observational cohort study was designed using the IBM MarketScan and Medicare databases, 2009-2015.
As a part of our continuing search for insect and arthropod development regulators from Brazilian restinga vegetation of the Rio de Janeiro State, crude extracts, purified fractions and essential oils were submitted to screening tests seeking for biological activities on the development of the insects Rhodnius prolixus, Dysdercus peruvianus, Oncopeltus fasciatus and Rhipicephalus (Boophilus) microplus. Up to now, 102 secondary metabolites have been detected in the fractions, among them monoterpenes, sesquiterpenes and two triterpenes which were obtained from the species, Eugenia sulcata, Pilocarpus spicatus, Manilkara subsericea, Myrciaria floribunda and Zanthoxylum caribaeum. These secondary plant metabolites are considered of interest for the use of studies related to arthropod endocrinology, vector-parasite interaction system, and population control of vector insect and agricultural pest.
View Article and Find Full Text PDFTick infestation in cattle reflects the main cause of economic loss to cattle producers. This is due to several reasons but mainly to their ability to feed on blood and generate a huge amount of eggs. Lipid transport in arthropods is achieved by highly specialized hemolymphatic lipoproteins, which resemble those described in vertebrate blood.
View Article and Find Full Text PDFInsect trypanosomatids are inhabitants of the insect digestive tract. These parasites can be either monoxenous or dixenous. Plant trypanosomatids are known as insect trypanosomatids once they and are transmitted by phytophagous insects.
View Article and Find Full Text PDFZanthoxylum caribaeum Lamarck (Rutaceae) is plant species with a variety of medical applications, including insecticidal activity. This study determined the bioacaricidal activity of the essential oil from Z. caribaeum leaves against engorged Rhipicephalus (Boophilus) microplus (Canestrini, 1887) females using the adult immersion test.
View Article and Find Full Text PDFThe cattle tick, Rhipicephalus (Boophilus) microplus, has caused serious harm to livestock raising in Brazil, considering the costs of controlling it, loss of revenue due to smaller production of milk and meat, and damage to leather, in addition to transmitting diseases. The use of medicinal plants is considered an alternative to the recurring resistance to chemicals. Due to the need for efficient alternatives with less environmental impact, this study aimed to develop contact formulations with essential oils from the Java citronella (Cymbopogon winterianus) and clove (Syzygium aromaticum) plants and to assess in vitro the effects in different stages of the tick cycle.
View Article and Find Full Text PDFBackground And Purpose: Transient receptor potential vanilloid subtype 3 (TRPV3) is implicated in nociception and certain skin conditions. As such, it is an attractive target for pharmaceutical research. Understanding of endogenous TRPV3 function and pharmacology remains elusive as selective compounds and native preparations utilizing higher throughput methodologies are lacking.
View Article and Find Full Text PDFBackground: Rhodnius prolixus is a blood-sucking bug vector of Trypanosoma cruzi and T. rangeli. T.
View Article and Find Full Text PDFBr J Pharmacol
February 2013
Background And Purpose: Evidence suggests that phosphorylation of TRPV1 is an important component underlying its aberrant activation in pathological pain states. To date, the detailed pharmacology of diverse TRPV1 receptor agonists and antagonists has yet to be reported for native TRPV1 under phosphorylating conditions. Our goal was to optimize a relatively high-throughput methodology to allow pharmacological characterization of the native TRPV1 receptor using a spinal cord neuropeptide release assay under naive and phosphorylating states.
View Article and Find Full Text PDFLeishmania amazonensis lacks a de novo mechanism for cholesterol synthesis and therefore must scavenge this lipid from the host environment. In this study we show that the L. amazonensis takes up and metabolizes human LDL(1) particles in both a time and dose-dependent manner.
View Article and Find Full Text PDFLeishmaniasis is a tropical disease caused by protozoan parasites of the genus Leishmania which affects 12 million people worldwide. The discovery of drugs for the treatment of leishmaniasis is a pressing concern in global health programs. The aim of this study aim was to evaluate the leishmanicidal effect of piperine and its derivatives/analogues on Leishmania amazonensis.
View Article and Find Full Text PDFWe investigated the effects of platelet-activating factor (PAF) on the interaction of Trypanosoma cruzi with Rhodnius prolixus. The parasites (epimastigotes) were treated with PAF and/or WEB 2086 (PAF antagonist) for 1 h prior to the interaction experiments. PAF stimulated both in vivo and ex vivo interactions between T.
View Article and Find Full Text PDFTransbound Emerg Dis
April 2010
The current study evaluates the protein and lipid profile of haemolymph of Rhipicephalus (Boophilus) microplus engorged females infected by Metarhizium anisopliae, Beauveria bassiana or Fusarium oxysporum. Ticks were immersed or inoculated with conidial suspension. Haemolymph was collected from the dorsal surface of engorged females.
View Article and Find Full Text PDFSazetidine-A has been recently proposed to be a "silent desensitizer" of alpha4beta2 nicotinic acetylcholine receptors (nAChRs), implying that it desensitizes alpha4beta2 nAChRs without first activating them. This unusual pharmacological property of sazetidine-A makes it, potentially, an excellent research tool to distinguish between the role of activation and desensitization of alpha4beta2 nAChRs in mediating the central nervous system effects of nicotine itself, as well as those of new nicotinic drugs. We were surprised to find that sazetidine-A potently and efficaciously stimulated nAChR-mediated dopamine release from rat striatal slices, which is mediated by alpha4beta2(*) and alpha6beta2(*) subtypes of nAChR.
View Article and Find Full Text PDFLipid transport in arthropods is achieved by highly specialized lipoproteins, which resemble those described in vertebrate blood. Here we describe purification and characterization of the lipid-apolipoprotein complex, lipophorin (Lp), from adults and larvae of the cowpea weevil Callosobruchus maculatus. We also describe the Lp-mediated lipid transfer to developing oocytes.
View Article and Find Full Text PDFA chimera comprising the N-terminal region of the human alpha7 nicotinic acetylcholine receptor, fused to the transmembrane/C-terminal domains of the mouse serotonin 5-HT3 receptor, was constructed. Injection of the chimera cDNA into Xenopus oocytes, or transient transfection in human embryonic kidney (HEK-293) cells, resulted in the expression of functional channels that were sensitive to nicotinic acetylcholine, but not serotonin receptor ligands. In both systems, the responses obtained from chimeric receptors inactivated more slowly than those recorded following activation of wild-type alpha7 receptors.
View Article and Find Full Text PDFDuring its life cycle Trypanosoma rangeli crosses the hemolymph of its invertebrate host. In the present study, we demonstrate for the first time the uptake of lipophorin (Lp), the main lipid-transporting particle of insect hemolymph. We observed that living T.
View Article and Find Full Text PDFWe have characterized the serum lipoprotein profile and localized the serum paraoxonase activity of pacu, Piaractus mesopotamicus, a tropical fish species. The total lipoprotein profile of pacu serum obtained after KBr density ultracentrifugation shows the predominance of HDL (1.1267 g/mL).
View Article and Find Full Text PDFObjective: Measures of cholinergic transmitter activity were investigated in patients with autism because of reported neuropathological abnormalities in cholinergic nuclei in the basal forebrain.
Method: Levels of cholinergic enzyme and receptor activity were measured in the frontal and parietal cerebral cortex of deceased autistic adults, similarly aged normal adults without mental retardation, and nonautistic mentally retarded adults. The immunoreactivity levels of brain-derived neurotrophic factor and nerve growth factor were measured in the basal forebrain.
The molecular identity of a gene which encodes the pore-forming subunit (alpha1G) of a member of the family of low-voltage-activated, T-type, voltage-dependent calcium channels has been described recently. Although northern mRNA analyses have shown alpha1G to be expressed predominantly in the brain, the detailed cellular distribution of this protein in the central nervous system (CNS) has not yet been reported. The current study describes the preparation of a subunit specific alpha1G riboprobe and antiserum which have been used in parallel in situ mRNA hybridization and immunohistochemical studies to localize alpha1G in the mature rat brain.
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