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1.
J Med Entomol ; 61(3): 678-685, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38366896

RESUMO

Volatile pyrethroids are effective in reducing mosquito populations and repelling vectors away from hosts. However, many gaps in knowledge exist for the sublethal impacts of volatile pyrethroids on mosquitoes. To that end, transfluthrin exposures were conducted on a field strain of Aedes albopictus (Skuse) held as a laboratory colony. Dose-response analysis was conducted on both sexes at either 1-4 days old or 5-10 days old. Resultant concentration data were used to evaluate the LC20 and LC50 values in various mate pairings of treatments and controls in which either the male or female was from a selectively treated group and mated with a counterpart that was treated independently. Blood feeding proportion, delayed mortality after a 24-h recovery period, egg collection totals, and F1 larval survival were determined following transfluthrin treatment in the F0, but outcomes were not significant. In contrast, sterility was predicated on male treatment, with treated females resulting in higher overall egg viability. Treated males in the mating pair resulted in significantly lower egg viability and accelerated larval hatch in the F1. Additionally, the presence of sperm in female spermathecae was significantly diminished in test groups containing treated male mosquitoes. Male sublethal effects may be a critical determinant of a mixed population's reproductive success.


Assuntos
Aedes , Ciclopropanos , Fertilidade , Fluorbenzenos , Inseticidas , Animais , Aedes/efeitos dos fármacos , Masculino , Ciclopropanos/farmacologia , Feminino , Inseticidas/farmacologia , Fertilidade/efeitos dos fármacos , Fluorbenzenos/farmacologia , Controle de Mosquitos
2.
Stroke ; 53(10): 3004-3013, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36017704

RESUMO

BACKGROUND: Atherosclerosis is the leading cause of cardiovascular disease worldwide, including in China. Primary prevention, through lipid-lowering, could avert development of atherosclerosis. Carotid intima-media thickness (CIMT) is a well-validated measure of atherosclerosis used in intervention studies as the primary outcome and alternative end point for cardiovascular disease events. METHODS: This randomized, double-blind, placebo-controlled, multicenter, parallel-group study assessed the effects of rosuvastatin 20 mg/d compared with placebo on progression of CIMT over 104 weeks in Chinese people with subclinical atherosclerosis. The primary end point was the annualized rate of change in mean of the maximum CIMT measurements taken 7× over the study period from each of 12 carotid artery sites (near and far walls of the right and left common carotid artery, carotid bulb, and internal carotid artery). Secondary end points included CIMT changes at different artery sites and lipid-parameter changes. Safety was also assessed. RESULTS: Participants were randomized (1:1) to receive rosuvastatin (n=272) or placebo (n=271). Baseline characteristics were well balanced between groups. The change in mean of the maximum CIMT of the 12 carotid sites was 0.0038 mm/y (95% CI, -0.0023-0.0100) for the rosuvastatin group versus 0.0142 mm/y (95% CI, 0.0080-0.0204) for the placebo group, with a difference of -0.0103 mm/y (95% CI, -0.0191 to -0.0016; P=0.020). For the CIMT secondary end points, the results were generally consistent with the primary end point. There were clinically relevant improvements in lipid parameters with rosuvastatin. We observed an adverse-event profile consistent with the known safety profile of rosuvastatin. CONCLUSIONS: Rosuvastatin 20 mg/d significantly reduced the progression of CIMT over 2 years in Chinese adults with subclinical atherosclerosis and was well tolerated. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT02546323.


Assuntos
Aterosclerose , Doenças Cardiovasculares , Doenças das Artérias Carótidas , Adulto , Aterosclerose/diagnóstico por imagem , Aterosclerose/tratamento farmacológico , Doenças Cardiovasculares/tratamento farmacológico , Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/tratamento farmacológico , Espessura Intima-Media Carotídea , Progressão da Doença , Fluorbenzenos/farmacologia , Fluorbenzenos/uso terapêutico , Humanos , Lipídeos/farmacologia , Lipídeos/uso terapêutico , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Rosuvastatina Cálcica/farmacologia , Rosuvastatina Cálcica/uso terapêutico , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico
4.
ChemMedChem ; 17(3): e202100637, 2022 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-34784449

RESUMO

Arylsulfonamides are ubiquitous in a number of anticancer agents, and fluorine substitution on aromatic rings often improves drug profile. Herein, a series of novel pentafluorobenzenesulfonamide derivatives with different molecular scaffolds were readily synthesized and assessed for their antitumor activities against multiple cancer cell lines, including A549, HepG2, HuCCA-1, and MOLT-3. Dihydroimidazoline-containing analogue and its Diels-Alder cycloadducts exhibited enhanced cytotoxicity at micromolar range while the incorporation of other heterocyclic cores via nucleophilic substitution reaction resulted in diminished potency. Selected analogues were shown to induce the accumulation of cleaved forms of Casp-9, Casp-7 and PARP in cancer cells, indicating intrinsic apoptosis via a caspase-dependent process.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Fluorbenzenos/farmacologia , Sulfonamidas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Fluorbenzenos/síntese química , Fluorbenzenos/química , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , Sulfonamidas/síntese química , Sulfonamidas/química
5.
Kidney Blood Press Res ; 46(6): 702-713, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34818247

RESUMO

OBJECTIVE: Kidney renal clear cell carcinoma (KIRC) is a common cancer with high morbidity and mortality in renal cancer. Thus, the transcriptome data of KIRC patients in The Cancer Genome Atlas (TCGA) database were analyzed and drug candidates for the treatment of KIRC were explored through the connectivity map (CMap) database. METHODS: The transcriptome data of KIRC patients were downloaded from TCGA database, and KIRC-associated hub genes were screened out through differential analysis and protein-protein interaction (PPI) network analysis. Afterward, the CMap database was used to select drug candidates for KIRC treatment, and the drug-targeted genes were obtained through the STITCH database. A PPI network was constructed by combining drug-targeted genes with hub genes that affected the pathogenesis of KIRC to obtain final hub genes. Finally, combining hub genes and KIRC-associated hub genes, the pathways affected by drugs were explored by pathway enrichment analysis. RESULTS: A total of 2,312 differentially expressed genes were found in patients, which were concentrated in immune cell activity, cytokine, and chemokine secretion pathways. Drug screening disclosed 5 drug candidates for KIRC treatment: fedratinib, Ly344864, geldanamycin, AS-605240, and luminespib. Based on drug-targeted genes and KIRC-associated hub genes, 16 hub genes were screened out. Pathway enrichment analysis revealed that drugs mainly affected pathways such as neuroactive ligand pathways, cell adhesion, and chemokines. CONCLUSION: The above results indicated that fedratinib, LY 344864, geldanamycin, AS-605240, and luminespib could be used as candidates for KIRC therapy. The findings from this study will make contributions to the treatment of KIRC in the future.


Assuntos
Antineoplásicos/farmacologia , Carcinoma de Células Renais/tratamento farmacológico , Descoberta de Drogas , Neoplasias Renais/tratamento farmacológico , Benzoquinonas/farmacologia , Carbazóis/farmacologia , Carcinoma de Células Renais/genética , Ensaios de Seleção de Medicamentos Antitumorais , Fluorbenzenos/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Renais/genética , Lactamas Macrocíclicas/farmacologia , Pirrolidinas/farmacologia , Sulfonamidas/farmacologia , Transcriptoma/efeitos dos fármacos
6.
Pak J Pharm Sci ; 34(3(Supplementary)): 1089-1096, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34602437

RESUMO

Depression, a common mental disorder, is one of the major contributors to the overall global burden with more than 264 million individuals affected worldwide. Monoamine oxidase inhibitors (MAOIs) have well-known efficacy for treating depression and other related disorders. Herein we report the implementation of extensive in-silico calculations to predict the mono-amine inhibitory potential of an in-house library of piperazine-based compounds. In this connection, a multistep virtual screening protocol based on pharmacophore modeling, molecular docking and Quantitative Structure-Activity Relationship (QSAR) was carried out by MOE. Further, to assess its ability to cross the blood brain barrier, ADME properties of the compounds were predicted. Compounds predicted the highest enzyme inhibition by QSAR was synthesized for experimental validation. Both the synthesized compounds (I15 and I21) presented good strength against Monoamine Oxidase in in vitro enzyme inhibitory activity.


Assuntos
Antidepressivos/farmacologia , Fluorbenzenos/farmacologia , Simulação de Acoplamento Molecular , Inibidores da Monoaminoxidase/farmacologia , Piperazinas/farmacologia , Relação Quantitativa Estrutura-Atividade , Barreira Hematoencefálica/metabolismo , Simulação por Computador , Transtorno Depressivo/tratamento farmacológico , Avaliação Pré-Clínica de Medicamentos , Técnicas In Vitro
7.
Cell Rep ; 36(11): 109714, 2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34525364

RESUMO

Lysergic acid diethylamide (LSD) produces hallucinations, which are perceptions uncoupled from the external environment. How LSD alters neuronal activities in vivo that underlie abnormal perceptions is unknown. Here, we show that when rats run along a familiar track, hippocampal place cells under LSD reduce their firing rates, their directionality, and their interaction with visual cortical neurons. However, both hippocampal and visual cortical neurons temporarily increase firing rates during head-twitching, a behavioral signature of a hallucination-like state in rodents. When rats are immobile on the track, LSD enhances cortical firing synchrony in a state similar to the wakefulness-to-sleep transition, during which the hippocampal-cortical interaction remains dampened while hippocampal awake reactivation is maintained. Our results suggest that LSD suppresses hippocampal-cortical interactions during active behavior and during immobility, leading to internal hippocampal representations that are degraded and isolated from external sensory input. These effects may contribute to LSD-produced abnormal perceptions.


Assuntos
Hipocampo/efeitos dos fármacos , Dietilamida do Ácido Lisérgico/farmacologia , Córtex Visual/efeitos dos fármacos , Animais , Comportamento Animal/efeitos dos fármacos , Região CA1 Hipocampal/fisiologia , Eletromiografia , Fluorbenzenos/farmacologia , Hipocampo/fisiologia , Masculino , Neurônios/fisiologia , Piperidinas/farmacologia , Ratos , Ratos Long-Evans , Sono/fisiologia , Córtex Visual/patologia , Córtex Visual/fisiologia , Vigília/fisiologia
8.
Behav Brain Res ; 415: 113521, 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34391796

RESUMO

Methamphetamine withdrawal can induce intense cravings leading to relapse. Contexts/cues paired with chronic methamphetamine use develop incentive motivational properties, promoting future drug-seeking and taking behavior. Research has shown that, in adult male rats, the selective 5-HT2A receptor antagonist M100907 attenuates the acquisition of methamphetamine-induced conditioned place preference (CPP), a measure that examines conditioned associations between the rewarding properties of drugs and contexts. However, these findings have not been extended to adult female rats. The present study investigated the effects of M100907 on the acquisition of methamphetamine-CPP in adult female rats. During conditioning, rats were administered M100907 (0, 0.025, 0.25 mg/kg, i.p.) 15 min before methamphetamine (1 mg/kg, i.p.) and then placed into their initially non-preferred chamber for 30 min, or administered saline and placed into their initially preferred chamber for 30 min. Conditioning sessions were separated by four hours. Following four days of conditioning, the effects of M100907 on the acquisition of methamphetamine-CPP were assessed during a 15 min drug-free test trial. Pretreatment with M100907 dose-dependently attenuated the acquisition of methamphetamine-induced CPP. Blocking 5-HT2A receptors with a low dose of the selective antagonist M100907 attenuated the rewarding effects of methamphetamine in adult female rats. These data provide further evidence that the 5-HT2A receptor subtype is involved in the behavioral effects of methamphetamine.


Assuntos
Comportamento Animal/efeitos dos fármacos , Estimulantes do Sistema Nervoso Central/farmacologia , Condicionamento Clássico/efeitos dos fármacos , Metanfetamina/farmacologia , Antagonistas do Receptor 5-HT2 de Serotonina/farmacologia , Animais , Estimulantes do Sistema Nervoso Central/administração & dosagem , Feminino , Fluorbenzenos/farmacologia , Masculino , Metanfetamina/administração & dosagem , Piperidinas/farmacologia , Ratos , Ratos Long-Evans , Antagonistas do Receptor 5-HT2 de Serotonina/administração & dosagem
9.
PLoS Negl Trop Dis ; 15(7): e0009546, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34237076

RESUMO

BACKGROUND: Volatile pyrethroid insecticides, such as transfluthrin, have received increasing attention for their potent repellent activities in recent years for controlling human disease vectors. It has been long understood that pyrethroids kill insects by promoting activation and inhibiting inactivation of voltage-gated sodium channels. However, the mechanism of pyrethroid repellency remains poorly understood and controversial. METHODOLOGY/PRINCIPAL FINDINGS: Here, we show that transfluthrin repels Aedes aegypti in a hand-in-cage assay at nonlethal concentrations as low as 1 ppm. Contrary to a previous report, transfluthrin does not elicit any electroantennogram (EAG) responses, indicating that it does not activate olfactory receptor neurons (ORNs). The 1S-cis isomer of transfluthrin, which does not activate sodium channels, does not elicit repellency. Mutations in the sodium channel gene that reduce the potency of transfluthrin on sodium channels decrease transfluthrin repellency but do not affect repellency by DEET. Furthermore, transfluthrin enhances DEET repellency. CONCLUSIONS/SIGNIFICANCE: These results provide a surprising example that sodium channel activation alone is sufficient to potently repel mosquitoes. Our findings of sodium channel activation as the principal mechanism of transfluthrin repellency and potentiation of DEET repellency have broad implications in future development of a new generation of dual-target repellent formulations to more effectively repel a variety of human disease vectors.


Assuntos
Aedes/efeitos dos fármacos , Ciclopropanos/farmacologia , Fluorbenzenos/farmacologia , Proteínas de Insetos/metabolismo , Repelentes de Insetos/farmacologia , Canais de Sódio/metabolismo , Aedes/genética , Aedes/metabolismo , Animais , Ciclopropanos/química , Fluorbenzenos/química , Proteínas de Insetos/genética , Repelentes de Insetos/química , Isomerismo , Canais de Sódio/genética
10.
J Neurosci ; 41(34): 7246-7258, 2021 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-34261701

RESUMO

Previously, studies using human neuroimaging and excitotoxic lesions in non-human primate have demonstrated an important role of ventrolateral prefrontal cortex (vlPFC) in higher order cognitive functions such as cognitive flexibility and the planning of behavioral sequences. In the present experiments, we tested effects on performance of temporary inactivation (using GABA receptor agonists) and dopamine (DA) D2 and 5-HT2A-receptor (R) blockade of vlPFC via local intracerebral infusions in the marmoset. We trained common marmosets to perform spatial self-ordered sequencing tasks in which one cohort of animals performed two and three response sequences on a continuously varying spatial array of response options on a touch-sensitive screen. Inactivation of vlPFC produced a marked disruption of accuracy of sequencing which also exhibited significant error perseveration. There were somewhat contrasting effects of D2 and 5-HT2A-R blockade, with the former producing error perseveration on incorrect trials, though not significantly impairing accuracy overall, and the latter significantly impairing accuracy but not error perseveration. A second cohort of marmosets were directly compared on performance of fixed versus variable spatial arrays. Inactivation of vlPFC again impaired self-ordered sequencing, but only with varying, and not fixed spatial arrays, the latter leading to the consistent use of fewer, preferred sequences. These findings add to evidence that vlPFC is implicated in goal-directed behavior that requires higher-order response heuristics that can be applied flexibly over different (variable), as compared with fixed stimulus exemplars. They also show that dopaminergic and serotonergic chemomodulation has distinctive effects on such performance.SIGNIFICANCE STATEMENT This investigation employing local intracerebral infusions to inactivate the lateral prefrontal cortex (PFC) of the New World marmoset reveals the important role of this region in self-ordered response sequencing in variable but not fixed spatial arrays. These novel findings emphasize the higher order functions of this region, contributing to cognitive flexibility and planning of goal directed behavior. The investigation also reports for the first time somewhat contrasting neuromodulatory deficits produced by infusions of dopamine (DA) D2 and 5-HT2A receptor (R) antagonists into the same region, of possible significance for understanding cognitive deficits produced by anti-psychotic drugs.


Assuntos
Dopamina/fisiologia , Córtex Pré-Frontal/fisiologia , Desempenho Psicomotor/fisiologia , Serotonina/fisiologia , Ácido gama-Aminobutírico/fisiologia , Animais , Antipsicóticos/efeitos adversos , Baclofeno/farmacologia , Callithrix , Transtornos Cognitivos/induzido quimicamente , Antagonistas dos Receptores de Dopamina D2/farmacologia , Fluorbenzenos/farmacologia , Agonistas GABAérgicos/farmacologia , Objetivos , Memória de Curto Prazo/fisiologia , Muscimol/farmacologia , Piperidinas/farmacologia , Córtex Pré-Frontal/efeitos dos fármacos , Desempenho Psicomotor/efeitos dos fármacos , Antagonistas do Receptor 5-HT2 de Serotonina/farmacologia , Comportamento Espacial , Sulpirida/farmacologia
11.
Int J Neuropsychopharmacol ; 24(9): 749-757, 2021 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-34228806

RESUMO

BACKGROUND: Though drugs binding to serotonergic 5-HT2A receptors have long been claimed to influence human anxiety, it remains unclear if this receptor subtype is best described as anxiety promoting or anxiety dampening. Whereas conditioned fear expressed as freezing in rats is modified by application of 5-HT2A-acting drugs locally into different brain regions, reports on the effect of systemic administration of 5-HT2A receptor agonists and 5-HT2A antagonists or inverse agonists on this behavior remain sparse. METHODS: We assessed the possible impact of systemic administration of 5-HT2A receptor agonists, 5-HT2A receptor inverse agonists, and a selective serotonin reuptake inhibitor (SSRI)-per se or in combination-on the freezing displayed by male rats when re-exposed to a conditioning chamber in which they received foot shocks 7 days earlier. RESULTS: The 5-HT2A receptor agonists psilocybin and 25CN-NBOH induced a reduction in conditioned fear that was countered by pretreatment with 5-HT2A receptor inverse agonist MDL 100907. While both MDL 100907 and another 5-HT2A receptor inverse agonist, pimavanserin, failed to impact freezing per se, both compounds unmasked a robust fear-reducing effect of an SSRI, escitalopram, which by itself exerted no such effect. CONCLUSIONS: The results indicate that 5-HT2A receptor activation is not a prerequisite for normal conditioned freezing in rats but that this receptor subtype, when selectively over-activated prior to expression, exerts a marked fear-reducing influence. However, in the presence of an SSRI, the 5-HT2A receptor, on the contrary, appears to counter an anti-freezing effect of the enhanced extracellular serotonin levels following reuptake inhibition.


Assuntos
Comportamento Animal/efeitos dos fármacos , Condicionamento Clássico/efeitos dos fármacos , Medo/efeitos dos fármacos , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Agonistas do Receptor 5-HT2 de Serotonina/farmacologia , Antagonistas do Receptor 5-HT2 de Serotonina/farmacologia , Animais , Compostos Bicíclicos com Pontes/farmacologia , Fluorbenzenos/farmacologia , Ligantes , Masculino , Metilaminas/farmacologia , Piperidinas/farmacologia , Psilocibina/farmacologia , Ratos , Ratos Sprague-Dawley , Ureia/análogos & derivados , Ureia/farmacologia
12.
Parasit Vectors ; 14(1): 265, 2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34016149

RESUMO

BACKGROUND: The human landing catch (HLC) measures human exposure to mosquito bites and evaluates the efficacy of vector control tools. However, it may expose volunteers to potentially infected mosquitoes. The mosquito electrocuting trap (MET) and BG-Sentinel traps (BGS) represent alternative, exposure-free methods for sampling host-seeking mosquitoes. This study investigates whether these methods can be effectively used as alternatives to HLC for measuring the efficacy of transfluthrin emanator against Aedes aegypti. METHODS: The protective efficacy (PE) of freestanding passive transfluthrin emanators (FTPEs), measured by HLC, MET and BGS, was compared in no-choice and choice tests. The collection methods were conducted 2 m from an experimental hut with FTPEs positioned at 3 m on either side of them. For the choice experiment, a competitor HLC was included 10 m from the first collection point. One hundred laboratory-reared Ae. aegypti mosquitoes were released and collected for 3 consecutive h. RESULTS: In the no-choice test, each method measured similar PE: HLC: 66% (95% confidence interval [CI]: 50-82), MET: 55% (95% CI: 48-63) and BGS: 64% (95% CI: 54-73). The proportion of mosquitoes recaptured was consistent between methods (20-24%) in treatment and varied (47-71%) in the control. However, in choice tests, the PE measured by each method varied: HLC: 37% (95% CI: 25-50%), MET: 76% (95% CI: 61-92) and BGS trap: 0% (95% CI: 0-100). Recaptured mosquitoes were no longer consistent between methods in treatment (2-26%) and remained variable in the control (7-42%). FTPE provided 50% PE to the second HLC 10 m away. In the control, the MET and the BGS were less efficacious in collecting mosquitoes in the presence of a second HLC. CONCLUSIONS: Measuring the PE in isolation was fairly consistent for HLC, MET and BGS. Because HLC is not advisable, it is reasonable to use either MET or BGS as a proxy for HLC for testing volatile pyrethroid (VP) in areas of active arbovirus-endemic areas. The presence of a human host in close proximity invalidated the PE estimates from BGS and METs. Findings also indicated that transfluthrin can protect multiple people in the peridomestic area and that at short range mosquitoes select humans over the BGS.


Assuntos
Aedes/efeitos dos fármacos , Aedes/fisiologia , Ciclopropanos/farmacologia , Fluorbenzenos/farmacologia , Controle de Mosquitos/métodos , Substâncias Protetoras/farmacologia , Adulto , Animais , Comportamento Alimentar , Feminino , Humanos , Masculino , Controle de Mosquitos/instrumentação
13.
J Econ Entomol ; 114(2): 928-936, 2021 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-33503251

RESUMO

Field development for optimizing the use patterns of spatial repellents are an ongoing research need. To investigate volatile pyrethroids in blends containing multiple active ingredients, metofluthrin was formulated into a vegetation spray for application to foliage and mosquito harborage. Metofluthrin was compared by itself and in combination with Sector (permethrin), Hyperion (sumithrin), Onslaught Fast Cap (s-fenvalerate, prallethrin), and against a benchmark for comparison, OneGuard (λ-cyhalothrin, prallethrin, pyriproxyfen). Field sites with established Aedes albopictus (Skuse) (Diptera: Culicidae) populations were allocated as control and treatment and surveilled with both adult traps and oviposition cups before and after treatment. Adult mosquito reductions were consistently higher over 4 wk in the combination treatments and were comparable to OneGuard. In contrast, efficacy provided by metofluthrin alone or the standalone existing product (Sector, Hyperion, Onslaught) by were consistently less effective than OneGuard and the comparative blends. Additionally, poorly melanized and collapsing eggs were identified from mosquito adults collected at treated field sites. A 20-50% significant decrease in nonviable mosquito eggs, a 50% or more reduction in total eggs and an 80% or more reduction in adult mosquitoes collected at the local field sites was demonstrated across all metofluthrin-containing treatments. Metofluthrin applications both supplemented the adulticidal control of the selected pyrethroid-containing products and provided significant reduction in egg laying frequency and viability during monitoring of areas adjacent to the treated vegetation. Metofluthrin, and possibly other volatile ingredients, appears to have complex interactions for mosquito control in the field and could be unique as a supporting ingredient to other insecticides.


Assuntos
Aedes , Inseticidas , Animais , Ciclopropanos/farmacologia , Feminino , Fluorbenzenos/farmacologia , Controle de Mosquitos
14.
PLoS Negl Trop Dis ; 15(1): e0009036, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33497375

RESUMO

BACKGROUND: In the absence of vaccines or drugs, insecticides are the mainstay of Aedes-borne disease control. Their utility is challenged by the slow deployment of resources, poor community compliance and inadequate household coverage. Novel application methods are required. METHODOLOGY AND PRINCIPAL FINDINGS: A 10% w/w metofluthrin "emanator" that passively disseminates insecticide from an impregnated net was evaluated in a randomized trial of 200 houses in Mexico. The devices were introduced at a rate of 1 per room and replaced at 3-week intervals. During each of 7 consecutive deployment cycles, indoor resting mosquitoes were sampled using aspirator collections. Assessments of mosquito landing behaviours were made in a subset of houses. Pre-treatment, there were no differences in Aedes aegypti indices between houses recruited to the control and treatment arms. Immediately after metofluthrin deployment, the entomological indices between the trial arms diverged. Averaged across the trial, there were significant reductions in Abundance Rate Ratios for total Ae. aegypti, female abundance and females that contained blood meals (2.5, 2.4 and 2.3-times fewer mosquitoes respectively; P<0.001). Average efficacy was 60.2% for total adults, 58.3% for females, and 57.2% for blood-fed females. The emanators also reduced mosquito landings by 90% from 12.5 to 1.2 per 10-minute sampling period (P<0.05). Homozygous forms of the pyrethroid resistant kdr alleles V410L, V1016L and F1534C were common in the target mosquito population; found in 39%, 24% and 95% of mosquitoes collected during the trial. CONCLUSIONS/SIGNIFICANCE: This is the first randomized control trial to evaluate the entomological impact of any volatile pyrethroid on urban Ae. aegypti. It demonstrates that volatile pyrethroids can have a sustained impact on Ae. aegypti population densities and human-vector contact indoors. These effects occur despite the presence of pyrethroid-resistant alleles in the target population. Formulations like these may have considerable utility for public health vector control responses.


Assuntos
Aedes/efeitos dos fármacos , Ciclopropanos/farmacologia , Fluorbenzenos/farmacologia , Inseticidas/farmacologia , Controle de Mosquitos/métodos , Mosquitos Vetores/efeitos dos fármacos , Aedes/genética , Animais , Comportamento Animal , Dengue/transmissão , Entomologia , Características da Família , Feminino , Humanos , Resistência a Inseticidas/efeitos dos fármacos , Resistência a Inseticidas/genética , México , Mosquitos Vetores/genética , Prevalência , Piretrinas/farmacologia , Projetos de Pesquisa
15.
Parasit Vectors ; 14(1): 64, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33472661

RESUMO

BACKGROUND: Semi-field experiments with human landing catch (HLC) measure as the outcome are an important step in the development of novel vector control interventions against outdoor transmission of malaria since they provide good estimates of personal protection. However, it is often infeasible to determine whether the reduction in HLC counts is due to mosquito mortality or repellency, especially considering that spatial repellents based on volatile pyrethroids might induce both. Due to the vastly different impact of repellency and mortality on transmission, the community-level impact of spatial repellents can not be estimated from such semi-field experiments. METHODS: We present a new stochastic model that is able to estimate for any product inhibiting outdoor biting, its repelling effect versus its killing and disarming (preventing host-seeking until the next night) effects, based only on time-stratified HLC data from controlled semi-field experiments. For parameter inference, a Bayesian hierarchical model is used to account for nightly variation of semi-field experimental conditions. We estimate the impact of the products on the vectorial capacity of the given Anopheles species using an existing mathematical model. With this methodology, we analysed data from recent semi-field studies in Kenya and Tanzania on the impact of transfluthrin-treated eave ribbons, the odour-baited Suna trap and their combination (push-pull system) on HLC of Anopheles arabiensis in the peridomestic area. RESULTS: Complementing previous analyses of personal protection, we found that the transfluthrin-treated eave ribbons act mainly by killing or disarming mosquitoes. Depending on the actual ratio of disarming versus killing, the vectorial capacity of An. arabiensis is reduced by 41 to 96% at 70% coverage with the transfluthrin-treated eave ribbons and by 38 to 82% at the same coverage with the push-pull system, under the assumption of a similar impact on biting indoors compared to outdoors. CONCLUSIONS: The results of this analysis of semi-field data suggest that transfluthrin-treated eave ribbons are a promising tool against malaria transmission by An. arabiensis in the peridomestic area, since they provide both personal and community protection. Our modelling framework can estimate the community-level impact of any tool intervening during the mosquito host-seeking state using data from only semi-field experiments with time-stratified HLC.


Assuntos
Malária/prevenção & controle , Controle de Mosquitos/normas , Mosquitos Vetores/parasitologia , Animais , Anopheles/efeitos dos fármacos , Teorema de Bayes , Ciclopropanos/farmacologia , Feminino , Fluorbenzenos/farmacologia , Humanos , Mordeduras e Picadas de Insetos/prevenção & controle , Repelentes de Insetos , Malária/transmissão , Modelos Teóricos , Controle de Mosquitos/métodos , Odorantes
16.
Parasit Vectors ; 14(1): 42, 2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33430963

RESUMO

BACKGROUND: Novel malaria vector control approaches aim to combine tools for maximum protection. This study aimed to evaluate novel and re-evaluate existing putative repellent 'push' and attractive 'pull' components for manipulating the odour orientation of malaria vectors in the peri-domestic space. METHODS: Anopheles arabiensis outdoor human landing catches and trap comparisons were implemented in large semi-field systems to (i) test the efficacy of Citriodiol® or transfluthrin-treated fabric strips positioned in house eave gaps as push components for preventing bites; (ii) understand the efficacy of MB5-baited Suna-traps in attracting vectors in the presence of a human being; (iii) assess 2-butanone as a CO2 replacement for trapping; (iv) determine the protection provided by a full push-pull set up. The air concentrations of the chemical constituents of the push-pull set-up were quantified. RESULTS: Microencapsulated Citriodiol® eave strips did not provide outdoor protection against host-seeking An. arabiensis. Transfluthrin-treated strips reduced the odds of a mosquito landing on the human volunteer (OR 0.17; 95% CI 0.12-0.23). This impact was lower (OR 0.59; 95% CI 0.52-0.66) during the push-pull experiment, which was associated with low nighttime temperatures likely affecting the transfluthrin vaporisation. The MB5-baited Suna trap supplemented with CO2 attracted only a third of the released mosquitoes in the absence of a human being; however, with a human volunteer in the same system, the trap caught < 1% of all released mosquitoes. The volunteer consistently attracted over two-thirds of all mosquitoes released. This was the case in the absence ('pull' only) and in the presence of a spatial repellent ('push-pull'), indicating that in its current configuration the tested 'pull' does not provide a valuable addition to a spatial repellent. The chemical 2-butanone was ineffective in replacing CO2. Transfluthrin was detectable in the air space but with a strong linear reduction in concentrations over 5 m from release. The MB5 constituent chemicals were only irregularly detected, potentially suggesting insufficient release and concentration in the air for attraction. CONCLUSION: This step-by-step evaluation of the selected 'push' and 'pull' components led to a better understanding of their ability to affect host-seeking behaviours of the malaria vector An. arabiensis in the peri-domestic space and helps to gauge the impact such tools would have when used in the field for monitoring or control.


Assuntos
Comportamento Animal/efeitos dos fármacos , Repelentes de Insetos/normas , Malária/prevenção & controle , Controle de Mosquitos/métodos , Controle de Mosquitos/normas , Mosquitos Vetores/efeitos dos fármacos , Agricultura , Animais , Anopheles/efeitos dos fármacos , Anopheles/parasitologia , Ciclopropanos/farmacologia , Feminino , Fluorbenzenos/farmacologia , Habitação , Humanos , Mordeduras e Picadas de Insetos/prevenção & controle , Repelentes de Insetos/análise , Malária/transmissão , Mosquitos Vetores/parasitologia , Extratos Vegetais/farmacologia , Têxteis/análise
17.
J Med Entomol ; 58(2): 756-766, 2021 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-33078838

RESUMO

Exophilic vectors are an important contributor to residual malaria transmission. Wearable spatial repellents (SR) can potentially provide personal protection in early evening hours before people retire indoors. An SR prototype for passive delivery of transfluthrin (TFT) for protecting humans against nocturnal mosquitoes in Kanchanaburi, western Thailand, is evaluated. A plastic polyethylene terephthalate (PET) sheet (676 cm2) treated with 55-mg TFT (TFT-PET), attached to the back of short-sleeve vest worn by human collector, was evaluated under semifield and outdoor conditions. Field-caught, nonblood-fed female Anopheles minimus s.l. were released in a 40 m length, semifield screened enclosure. Two collectors positioned at opposite ends conducted 12-h human-landing collections (HLC). The outdoor experiment was conducted between treatments among four collectors at four equidistant positions who performed HLC. Both trials were conducted for 30 consecutive nights. TFT-PET provided 67% greater protection (P < 0.001) for 12 h compared with unprotected control, a threefold reduction in the attack. In outdoor trials, TFT-PET provided only 16% protection against An. harrisoni Harbach & Manguin (Diptera: Culicidae) compared with unprotected collector (P = 0.0213). The TFT-PET vest reduced nonanophelines landing by 1.4-fold compared with the PET control with a 29% protective efficacy. These findings suggest that TFT-PET had diminished protective efficacy in an open field environment. Nonetheless, the concept of a wearable TFT emanatory device has the potential for protecting against outdoor biting mosquitoes. Further development of portable SR tools is required, active ingredient selection and dose optimization, and more suitable device design and materials for advancing product feasibility.


Assuntos
Anopheles/efeitos dos fármacos , Ciclopropanos/farmacologia , Fluorbenzenos/farmacologia , Repelentes de Insetos/farmacologia , Animais , Culicidae/efeitos dos fármacos , Humanos , Mordeduras e Picadas de Insetos , Malária/prevenção & controle , Malária/transmissão , Controle de Mosquitos , Mosquitos Vetores/efeitos dos fármacos , Tailândia
18.
Addict Biol ; 26(3): e12926, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32458577

RESUMO

The relative value of and motivation for abused drugs often increases with drug experience and differs based on drug availability. Here, we determined how different intake patterns of fentanyl, a µ-opioid agonist, alter economic demand for fentanyl and how 5-HT2A receptor stimulation affects economic demand for fentanyl. We used a within-session demand threshold procedure to characterize changes in economic demand for fentanyl before and after intermittent or continuous access schedules. We subsequently tested the acute effects of 5-HT2A receptor stimulation with psychedelic 2,5-dimethoxy-4-iodoamphetamine (DOI) on economic demand for fentanyl. Extended fentanyl experience with both intermittent and continuous schedules increased fentanyl consumption at low cost (Q0 ), increased total fentanyl consumption, and decreased demand elasticity (α), indicating both schedules elevated motivation to self-administer fentanyl. Overall, the two schedules produced similar alterations in economic demand for fentanyl, although low-cost consumption (Q0 ) increased more in the continuous access group. Systemic injections of DOI (0.0-0.4 mg/kg, i.p.) dose-dependently produced economic demand changes in the opposite direction produced by fentanyl experience. DOI decreased motivation (increased "α"), decreased Q0 , and decreased total fentanyl consumption. The selective 5-HT2A antagonist, M100907 (0.3 mg/kg, i.p.), blocked the effects of DOI, indicating that DOI is acting through 5-HT2A receptors to alter economic demand for fentanyl. In an economic food demand experiment, DOI (0.4 mg/kg) also increased demand elasticity and reduced food consumption. These results demonstrate that both intermittent and continuous fentanyl experience raise the economic demand for fentanyl, and acute 5-HT2A receptor activation reduces economic demand for fentanyl and food.


Assuntos
Anfetaminas/farmacologia , Fentanila/farmacologia , Fluorbenzenos/farmacologia , Piperidinas/farmacologia , Agonistas do Receptor 5-HT2 de Serotonina/farmacologia , Animais , Relação Dose-Resposta a Droga , Interações Medicamentosas , Masculino , Ratos , Ratos Sprague-Dawley , Esquema de Reforço , Autoadministração
19.
Mol Pharmacol ; 99(2): 114-124, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33268552

RESUMO

The large-conductance calcium-activated potassium channel (BKCa channel) is expressed on various tissues and is involved in smooth muscle relaxation. The channel is highly expressed on urinary bladder smooth muscle cells and regulates the repolarization phase of the spontaneous action potentials that control muscle contraction. To discover novel chemical activators of the BKCa channel, we screened a chemical library containing 8364 chemical compounds using a cell-based fluorescence assay. A chemical compound containing an isoxazolyl benzene skeleton (compound 1) was identified as a potent activator of the BKCa channel and was structurally optimized through a structure-activity relationship study to obtain 4-(4-(4-chlorophenyl)-3-(trifluoromethyl)isoxazol-5-yl)benzene-1,3-diol (CTIBD). When CTIBD was applied to the treated extracellular side of the channel, the conductance-voltage relationship of the channel shifted toward a negative value, and the maximum conductance increased in a concentration-dependent manner. CTIBD altered the gating kinetics of the channel by dramatically slowing channel closing without effecting channel opening. The effects of CTIBD on bladder muscle relaxation and micturition function were tested in rat tissue and in vivo. CTIBD concentration-dependently reduced acetylcholine-induced contraction of urinary bladder smooth muscle strips. In an acetic acid-induced overactive bladder (OAB) model, intraperitoneal injection of 20 mg/kg CTIBD effectively restored frequent voiding contraction and lowered voiding volume without affecting other bladder function parameters. Thus, our results indicate that CTIBD and its derivatives are novel chemical activators of the bladder BKCa channel and potential candidates for OAB therapeutics. SIGNIFICANCE STATEMENT: The novel BKCa channel activator CTIBD was identified and characterized in this study. CTIBD directly activates the BKCa channel and relaxes urinary bladder smooth muscle of rat, so CTIBD can be a potential candidate for overactive bladder therapeutics.


Assuntos
Fluorbenzenos/farmacologia , Canais de Potássio Ativados por Cálcio de Condutância Alta/metabolismo , Músculo Liso/fisiologia , Bibliotecas de Moléculas Pequenas/farmacologia , Bexiga Urinária/fisiologia , Animais , Avaliação Pré-Clínica de Medicamentos , Feminino , Fluorbenzenos/química , Masculino , Estrutura Molecular , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Músculo Liso/metabolismo , Ratos , Relação Estrutura-Atividade , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/metabolismo , Micção/efeitos dos fármacos , Xenopus laevis
20.
Behav Brain Res ; 401: 113093, 2021 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-33359368

RESUMO

Psychedelic drugs acting as 5-hydroxyptryptamine 2A receptor (5-HT2AR) agonists have shown promise as viable treatments of psychiatric disorders, including obsessive-compulsive disorder. The marble burying test is a test of compulsive-like behavior in mice, and psychedelics acting as 5-HT2AR agonists can reduce digging in this test. We assessed the 5-HT2R contribution to the mechanisms of two 5-HT2A agonists on digging behavior in female NMRI mice, using citalopram as a reference compound. While the 5-HT2AR antagonist M100907 blocked the effect of DOI and the 5-HT2CR antagonist SB242084 blocked the effect of citalopram, neither antagonist blocked the effect of psilocybin. This study confirms 5-HT2AR agonism as a mechanism for reduced compulsive-like digging in the MB test and suggests that 5-HT2A and 5-HT2CRs can work in parallel on this type of behavior. Our results with psilocybin suggest that a 5-HT2R-independent mechanism also contributes to the effect of psilocybin on repetitive digging behavior.


Assuntos
Comportamento Compulsivo/tratamento farmacológico , Psilocibina/farmacologia , Receptor 5-HT2A de Serotonina/efeitos dos fármacos , Receptor 5-HT2C de Serotonina/efeitos dos fármacos , Agonistas do Receptor 5-HT2 de Serotonina/farmacologia , Antagonistas da Serotonina/farmacologia , Aminopiridinas/farmacologia , Anfetaminas/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Citalopram/farmacologia , Modelos Animais de Doenças , Feminino , Fluorbenzenos/farmacologia , Indóis/farmacologia , Camundongos , Piperidinas/farmacologia , Psilocibina/administração & dosagem , Agonistas do Receptor 5-HT2 de Serotonina/administração & dosagem , Antagonistas da Serotonina/administração & dosagem , Inibidores Seletivos de Recaptação de Serotonina/farmacologia
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