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1.
Insects ; 13(2)2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35206754

RESUMO

Interactive movements of bees facilitate the division and organization of collective tasks, notably when they need to face internal or external environmental challenges. Here, we present a Bayesian and computational approach to track the movement of several honey bee, Apis mellifera, workers at colony level. We applied algorithms that combined tracking and Kernel Density Estimation (KDE), allowing measurements of entropy and Probability Distribution Function (PDF) of the motion of tracked organisms. We placed approximately 200 recently emerged and labeled bees inside an experimental colony, which consists of a mated queen, approximately 1000 bees, and a naturally occurring beehive background. Before release, labeled bees were fed for one hour with uncontaminated diets or diets containing a commercial mixture of synthetic fungicides (thiophanate-methyl and chlorothalonil). The colonies were filmed (12 min) at the 1st hour, 5th and 10th days after the bees' release. Our results revealed that the algorithm tracked the labeled bees with great accuracy. Pesticide-contaminated colonies showed anticipated collective activities in peripheral hive areas, far from the brood area, and exhibited reduced swarm entropy and energy values when compared to uncontaminated colonies. Collectively, our approach opens novel possibilities to quantify and predict potential alterations mediated by pollutants (e.g., pesticides) at the bee colony-level.

2.
J Econ Entomol ; 114(4): 1480-1488, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34260688

RESUMO

In blueberry crops, there are multiple pest species, and some of those can be suppressed by natural enemies including parasitoid wasps and predators. Parasitoid wasps occur within the environment often tracking pest species for food resources to complete their lifecycle. These small wasps are also sensitive to agricultural environments including agrichemicals, habitat availability, and climate. We investigated how the structure of parasitoid communities varied between organic and conventional blueberry systems, and how the communities of these parasitoids varied within field spatial scales (forested border vs edge vs interior). With the lower intensity of agricultural interventions occurring in organic systems and forested borders, we predicted more stable parasitoid numbers that would be insulated from predicted climate variability. In our study, parasitoids were observed in low abundance in each cropping system, with community structure dependent on both management practice and field position. Unmanaged blueberry fields and forested field borders contained more parasitoid families, and in conventional systems, we saw fewer families present in the field interior as compared to field borders. In this first study to characterize Southern parasitoid communities in blueberry production systems, we observed over 50 genera of parasitoids, with a few dominant families (Braconidae and Ichneumonidae) that would contribute to biological control in blueberry systems. Overall, we captured few parasitoids, which indicates a potential vulnerability in biological control, and the need for further research using other sampling techniques to better understand these parasitoid communities.


Assuntos
Mirtilos Azuis (Planta) , Vespas , Agricultura , Animais , Ecossistema , Sudeste dos Estados Unidos
3.
Sci Total Environ ; 779: 146432, 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-33744575

RESUMO

Stingless bees such as Partamona helleri Friese play important roles in pollination of native plants and agricultural crops in the Neotropics. Global concerns about declining bee populations due to agrochemical pollutants have, however, been biased towards the honey bee, Apis mellifera Linnaeus. Here, we analysed the unintended effects of commercial formulations of a neonicotinoid insecticide, imidacloprid, and a fungicide mixture of thiophanate-methyl and chlorothalonil on color preference, respiration rates and group locomotory activities of both P. helleri and A. mellifera. Our results revealed that P. helleri foragers that were not exposed to pesticides changed their color preference during the course of a year. By contrast, we found that pesticide exposure altered the color preference of stingless bees in a concentration-dependent manner. In addition, imidacloprid decreased the overall locomotion of both bee species, whereas the fungicide mixture increased locomotion of only stingless bees. The fungicide mixture also reduced respiration rates of forager bees of both species. Forager bees of both species altered their color preference, but not their locomotory and respiration rates, when exposed to commercial formulations of each fungicidal mixture component (i.e., chlorothalonil and thiophanate-methyl). Our findings emphasize the importance of P. helleri as a model for Neotropical wild pollinator species in pesticide risk assessments, and also the critical importance of including groups of agrochemicals that are often considered to have minimal impact on pollinators, such as fungicides.


Assuntos
Agroquímicos , Inseticidas , Agroquímicos/toxicidade , Animais , Abelhas , Inseticidas/toxicidade , Locomoção , Polinização , Taxa Respiratória
4.
Sci Total Environ ; 718: 137328, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32325622

RESUMO

The plant-based biopesticides have been proposed as insect pest control tools that seem to be safer for the environment and human health when compared to synthetic conventional molecules. However, such assumptions are generally made without considering the absence of detrimental effects on sublethally-exposed non-target organisms or showing the physiological basis of the selective action of such botanical products. Thus, by using in silico-based and in vivo toxicological approaches, the present investigation aimed to disentangle the ecotoxicological selectivity of clove, Syzygium aromaticum, essential oil against the aphid Rhopalosiphum maidis and the non-target ladybeetle, Coleomegilla maculata. We also investigated whether the sublethal exposure to clove essential oil would affect the locomotory and predatory abilities of C. maculata. We found that the clove essential oil concentration estimated to kill 95% (LC95: 0.17 µL/cm2) of the aphids was lethal to <18% of C. maculata. Indeed, our in silico results reinforced such differential susceptibility, as it predicted that eugenol and ß-caryophyllene (i.e., the clove essential oil major components) bound to three potential molecular targets (i.e., transient receptor potential (TRP) channels, octopamine, and gamma-aminobutyric acid (GABA) receptors) of the aphids but only to the octopamine receptors of the ladybeetles. Additionally, the ladybeetles that were exposure to the clove essential oil exhibited unaffected abilities to locomote and to prey upon R. maidis aphids when compared to unexposed ladybeetles. Thus, by displaying lower toxicity against the ladybeetles, the clove essential oil represents a safer alternative tool to be integrated into programs aiming to manage aphid infestations.


Assuntos
Afídeos , Animais , Óleo de Cravo , Controle de Insetos , Óleos Voláteis , Syzygium
5.
J Econ Entomol ; 112(6): 3002-3006, 2019 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-31289814

RESUMO

Biological invasions are a global threat to agricultural crops worldwide. In the Neotropical region, the spotted-wing Drosophila [Drosophila suzukii (Matsumura)] has rapidly expanded its geographical range spreading throughout South America in recent years. Besides climatic factors, the remarkable success of its establishment and subsequent distribution in this region is closely dependent on the diversity and availability of host plants. We evaluated the host potential (e.g., as food and oviposition sources) of fruits of jabuticaba [Plinia cauliflora (Mart.) Kausel (Myrtales: Myrtaceae)], Barbados cherry (Malpighia emarginata DC) (Malpighiales: Malpighiaceae), bonnet pepper (Capsicum chinense Jacq.) (Solanales : Solanaceae), and coffee (Coffea arabica L.) (Gentianales : Rubiaceae) and their effects on the biological and physiological traits of D. suzukii. For the fruit types where fly emergence occurred, we assessed the biological and physiological performance of the flies and compared these parameters with those recorded for flies reared on strawberries (Fragaria × ananassa Duchesne) (Rosales : Rosaceae) and an artificial diet. Our results revealed that oviposition into fruits and completion of the life cycle occurred on Barbados cherries only. Furthermore, field surveys revealed a higher emergence rate of D. suzukii on undamaged ripe Barbados cherries than damaged ones. Moreover, flies developing on Barbados cherries and an artificial diet presented earlier emergence, shorter developmental time, lower number of adults per female, and a female-biased sex ratio compared to flies developing on strawberries. Overall, our findings demonstrated suitability of Barbados cherry as a host for D. suzukii, which renders management of D. suzukii in Neotropical region an even more challenging task.


Assuntos
Fragaria , Malpighiaceae , Animais , Barbados , Drosophila , Feminino , América do Sul
6.
Environ Pollut ; 255(Pt 1): 113153, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31520906

RESUMO

Plant essential oils are regarded as interesting alternative tools to be integrated into the management of pest insects. However, as they generally consist of mixtures of numerous molecules, the physiological basis for their action is unresolved. Here, we evaluated the effects of essential oil of the Neotropical plant Siparuna guianensis Aubl., commonly known as Negramina, against an important pest insect: the green peach aphid Myzus persicae (Sulzer), and also in two non-target natural enemies: the ladybeetle predators Coleomegilla maculata (DeGeer) and Eriopis connexa (Germar). In addition, we conducted a computational docking analysis for predicting the physical interactions between the two Negramina essential oil major constituents: ß-myrcene and 2-undocanone, and the transient receptor potential (TRP) channels as potential binding receptors in the aphid and ladybeetles. As the most important results, Negramina essential oil caused mortality in M. persicae aphids with an LC95 = 1.08 mg/cm2, and also significantly repelled the aphids at concentrations as low as 0.14 mg/cm2. Our computational docking analysis reinforced such selectivity actions as the Negramina essential oil major compounds (i.e., ß-myrcene and 2-undocanone) bound to the TRP channels of M. persicae but not to ladybeetle-related TRP channels. Interestingly, the exposure to the Negramina essential oil did not affect the predatory abilities of C. maculata but increased the abilities of E. connexa to prey upon M. persicae. Collectively, our findings provided a physiological basis for the insecticidal and selectivity potential of Negramina essential oil, reinforcing its potential as a tool to be used in integrated pest control programs.


Assuntos
Afídeos/efeitos dos fármacos , Besouros/efeitos dos fármacos , Repelentes de Insetos/farmacologia , Laurales/química , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Monoterpenos Acíclicos/análise , Animais , Óleos Voláteis/química , Óleos de Plantas/química
7.
J Bras Nefrol ; 35(1): 69-72, 2013.
Artigo em Português | MEDLINE | ID: mdl-23598755

RESUMO

INTRODUCTION: In recent years, a role for aldosterone in pathophysiology of metabolic syndrome and hypertension in this syndrome has been suggested. However, the treatment with antagonists of mineralocorticoid receptor in these individuals has not properly addressed. OBJECTIVE: To evaluate the effects of mineralocorticoid receptor blockade on blood pressure, inflammatory, metabolic and renal parameters in non-diabetic hypertensive individuals with the metabolic syndrome. METHODS: Twenty nine patients with metabolic syndrome were enrolled in a prospective protocol that consisted of 2 periods: baseline (2 weeks) in which demographic data were obtained and antihypertensive medicines were withdrawn, and treatment period when the individuals were treated with spironolactone 25-50 mg once-a-day, for 16 weeks. In both periods, inflammatory, metabolic and renal parameters were assessed and the 24-hour ambulatory blood pressure monitorization was performed. RESULTS: After spironolactone treatment, 24 hour systolic and diastolic blood pressure decreased from 143.5 ± 15.17 mmHg to 133.2 ± 17.34 mmHg (p = 0.025) and from 85.2 ± 11.10 mmHg to 79.3 ± 11.78 mmHg (p = 0.026), respectively. HDL-cholesterol increased from 44.0 ± 8.67 mg/dl to 49.0 ± 6.75mg/dl (p = 0.000) and C-reactive protein decreased significantly from 6.3 ± 7.54 mg/l to 4.6 ± 6.3 mg/l (p = 0.009). Fasting plasma glucose, insulin, HOMA-IR and triglycerides did not change significantly after mineralocorticoid receptor blockade. Estimated glomerular filtration rate did not change whereas the logarithm of albuminuria decreased significantly from 2.5 ± 0.92 to 2.0 ± 0.9 (p = 0.028). CONCLUSION: In hypertensive subjects with MS the administration of spironolactone in monotherapy was effective for hypertension control, decreased urinary albumin excretion and increased HDL-cholester ol plasma.


Assuntos
Albuminúria/fisiopatologia , Pressão Sanguínea/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Síndrome Metabólica/fisiopatologia , Antagonistas de Receptores de Mineralocorticoides/farmacologia , Antagonistas de Receptores de Mineralocorticoides/uso terapêutico , Obesidade/fisiopatologia , Espironolactona/farmacologia , Adolescente , Adulto , Albuminúria/complicações , Feminino , Humanos , Hipertensão/complicações , Masculino , Síndrome Metabólica/complicações , Pessoa de Meia-Idade , Obesidade/complicações , Estudos Prospectivos , Adulto Jovem
8.
Biosci. j. (Online) ; 33(2): 364-370, mar./apr. 2017. tab
Artigo em Inglês | LILACS | ID: biblio-966183

RESUMO

Thresholds for Somatic Cell Counts (SCC) and Total Bacterial Counts (TBC) in refrigerated raw milk have been stricter in Brazil since July 2014. We evaluated whether the composition of 11,051 milk samples delivered to processing plants in Paraná state, Brazil, by cooperative dairy farms, complies with government requirements and established changes. Milk quality was evaluated from June to August 2014, from dairy farms in three states. Data were obtained by infrared spectroscopy and flow cytometry. SCC was highest in June (p<0.05), when the highest number of samples and mean values was observed that did not comply with legal standards. No samples obtained in July complied with the requirements. The city in Mato Grosso do Sul state was the only one that met the legal requirements throughout the period studied. TBC did not vary (p>0.05) in the trimester, and none of the cities presented values below the maximum TBC allowed. Protein, fat and non-fat solids obtained complied with legal requirements. Total solids and lactose varied among the months (p<0.05), with highest values for total solids in June and for lactose in August. Milk samples did not comply with minimal requirements for SCC and TBC, and were not adjusted to more rigid quality standards.


Limites de contagem de células somáticas (CCS) e contagem bacteriana total (CBT) em leite cru refrigerado estão mais estritos no Brasil desde Julho de 2014. Foram avaliadas 11051 amostras de leite entregues para beneficiamento no Estado do Paraná, Brasil, por produtores de leite e cooperados e verificou-se se estas atendiam aos requisitos governamentais e às mudanças estabelecidas. A qualidade do leite foi avaliada de Junho a Agosto de 2014 em fazendas leiteiras de três estados. Os dados foram obtidos por espectroscopia em infravermelho e citometria de fluxo. CCS foi superior em Junho (p<0,05), quando foi observado maior número de amostras e valores médios que não estavam de acordo com os padrões legais. A cidade do Estado de Mato Grosso do Sul foi a única que cumpriu com os limites legais requeridos ao longo do período. CBT não apresentou variação (p>0,05) ao longo do trimestre, e nenhuma das cidades apresentou valores dentro do limite estabelecido para CBT. Proteína, gordura e sólidos não gordurosos estavam de acordo com os limites requeridos. Sólidos totais e lactose variaram ao longo dos meses (p<0,05), com valores elevados para sólidos totais em Junho e para lactose em Agosto. Amostras de leite não estavam de acordo com os requisitos mínimos de CCS e CBT, e não estão ajustadas aos padrões de qualidade mais rígidos.


Assuntos
Controle de Qualidade , Contagem de Células , Indústria de Laticínios , Carga Bacteriana , Composição de Alimentos
9.
Artigo em Português | LILACS | ID: lil-712284

RESUMO

O recurso à internet para obtenção de informações sobre saúde tem provocado avaliações geralmente favoráveis por parte de pacientes e médicos nas indagações a respeito. No entanto, com maior atenção, percebe-se que nem todos os profissionais ratificam essas avaliações ou comungam do otimismo dispensado a essa variável. O objetivo deste estudo foi alinhar seus desdobramentos na relação médico-paciente, buscando um contraponto entre o caráter facilitador e o caráter de desafios inerentes a essa inclusão, abordando, inclusive, seus riscos potenciais à adesão ao tratamento. Sobre a expansão desse recurso, acessível tanto aos médicos quanto ao público leigo, foram lançadas perguntas básicas: quem recorre aos portais de saúde, quando e por que o faz, e quais os desdobramentos desse recurso sobre o médico e sobre seu vínculo com o paciente? Pacientes e médicos se beneficiam do uso da internet. Os primeiros, adquirindo segurança e capacidade de participação no tratamento; os últimos, obtendo atualização e informação facilmente disponíveis. No entanto, alheios a qualquer regulamentação ou validação do que veiculam, os portais sobre saúde trazem também os riscos da informação enganosa, ou de seu mau uso, uma vez que, na falta de uma base teórica e de experiência prática, nem sempre é possível ao paciente lidar positivamente com os dados obtidos. Assim, sua atitude participativa pode vir a se transformar em confrontação e/ou autossuficiência, colocando em risco a relação médico-paciente e, consequentemente, a adesão ao tratamento...


The use of the internet to obtain health information has led to generally favorable reviews by patients and doctors in inquiries about it. However, when paying closer attention one is led to realize that not all professionals ratify these reviews or share the optimism with which this variable is addressed. This article aimed to align its ramifications in the patient-physician relationship, seeking a counterpoint between the facilitating and challenging aspects inherent to this inclusion, focusing, as well, the potential risks to adherence to treatment. Regarding the expansion of the use of internet as a source of health information accessible to both physicians and lay people, basic questions were launched: who consults health websites, why and when does he/she do it, and what are the repercussions of this action on the physician and also on his/her relationship with the patient? Patients and physicians benefit from the use of the internet. The former acquires safety and ability to participate in treatment; the latter gets easily available updated knowledge. However, disregarding regulations or validation about what they convey, health websites also bring the risks of misleading information, or of its misuse, since when there is lack of a theoretical basis and practical experience, not always can the patient deal positively with the obtained data. Thus, patient's participatory attitude may turn into confrontation and/or self-reliance, putting patient-physician relationship and, consequently, adherence to treatment at risk...


Assuntos
Avaliação em Saúde , Internet , Relações Médico-Paciente , Autocuidado
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