Chemical signaling and insect attraction is a conserved trait in yeasts

Orchestrated chemical signaling of single cells sounds to be a linchpin of emerging organization and multicellular life form. The social amoeba Dictiostelium discoiudium is a well-studied model organism to explore overall pictures of grouped behavior in developmental biology. The chemical waves secreted by aggregating Dictiostelium is a superb example of pattern formation. The waves are either circular or spiral in shape, according to the incremental population density of a self-aggregating community of individuals. Here, we revisit the spatiotemporal patterns that appear in an excitable medium due to synchronization of randomly firing individuals, but with a more parsimonies attitude. According to our model, a fraction of these individuals is refusal to amplify external stimulants. Our simulations indicate that the cells enhance the system's asymmetry and as a result, nucleate early sustainable spiral territory zones, provided that their relative population does not exceed a tolerable threshold.

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Eficiência da Armadilha “R. Bianco” para Captura do Percevejo Leptoglossus zonatus Dallas (Hemiptera: Coreidae), na Cultura do Milho

EntomoBrasilis ◽

10.12741/ebrasilis.v9i2.531 ◽

2016 ◽

Vol 9 (2) ◽

pp. 84-88 ◽

Cited By ~ 1

Author(s):

Marliton Rocha Barreto ◽

Ledonir Geovani Da Silva

Keyword(s):

Attraction Effect ◽

Monitoring And Control ◽

The Third ◽

Important Pest ◽

Volume Production ◽

Insect Attraction ◽

And Control

Resumo. O milho é o cereal com maior índice de consumo, tanto industrializado como in natura, atualmente. É o grão com maior volume de produção, sendo o Brasil o terceiro maior produtor, dessa maneira, faz-se necessário uma atenção especial voltada ao monitoramento e controle de certos invasores que comprometem sua produtividade. Dentre as pragas que podem afetar essa produtividade destacamos os percevejos (Hemiptera: Heteroptera), mais especificamente o percevejo-do-milho (Leptoglossus zonatus Dallas), que tem se mostrado uma importante praga para a cultura do milho. O presente trabalho teve por objetivo avaliar a eficiência de armadilhas caseiras do tipo “R. Bianco” na captura desse percevejo. Os experimentos foram conduzidos no Sitio Nossa Senhora Aparecida, localizado no município de Sinop, MT. As armadilhas foram divididas em 10 abertas e 10 fechadas e avaliadas com e sem isca por 20 dias. O delineamento utilizado foi o inteiramente casualizado (DIC) em esquema fatorial 2x2x2 com oito tratamentos e cinco repetições. As armadilhas sem iscas demonstraram maior eficiência, apresentando média superior na captura do percevejo em relação às armadilhas com isca. As armadilhas fechadas, em comparação com as abertas, demonstraram maior eficácia na retenção do inseto. O efeito da borda foi pouco representativo nesse experimento. Portanto, a presença da isca não influenciou na atração do inseto e os tratamentos submetidos ao teste sem isca apresentaram maiores quantidades e maior eficiência na captura de insetos. Levando a crer o efeito de atração do sal pelo percevejo e a localização de cada armadilha pouco influenciou na captura dos insetos.Trap Efficiency “R. Bianco” for Capture the insect Leptoglossus zonatus Dallas (Hemiptera: Coreidae) in Maize CropAbstract. Maize is the cereal with the highest consumption in both industrialized as fresh nowadays. It is the grain with higher volume production, Brazil is the third largest producer, need special attention focused on the monitoring and control of invaders who risk their productivity. Among the pests that can affect the productivity highlight the insects (Hemiptera: Heteroptera), more specifically the bedbugs corn (Leptoglossus zonatus Dallas), which has been an important pest for corn crops. Thus, this study aimed to evaluate the effectiveness of homemade traps R. Bianco in control of this insect. The experiments were conducted in Sitio Nossa Senhora Aparecida, in the municipality of Sinop, MT. Traps were divided into 10 open and 10 closed which were evaluated with and without baits by 20 days. The design was completely randomized (DIC) in a 2x2x2 factorial with eight treatments and five repetitions. Traps without baits showed greater efficiency, with an average higher in catching the bugs regarding the traps with bait. The trap closed as compared with the open, demonstrated greater efficacy in retaining the insect. The effect of edge was little representative in this experiment. Therefore, the presence of bait did not influence the insect attraction and treatments submitted to the bait without test showed higher quantities and more efficient insect capture. Leading us to believe the attraction effect of salt by bedbug and the location of each trap had little influence in the capture of insects.

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Prophylactic Activation of Shh Signaling Attenuates TBI-Induced Seizures in Zebrafish by Modulating Glutamate Excitotoxicity through Eaat2a

Biomedicines ◽

10.3390/biomedicines10010032 ◽

2021 ◽

Vol 10 (1) ◽

pp. 32

Author(s):

James Hentig ◽

Leah J. Campbell ◽

Kaylee Cloghessy ◽

Mijoon Lee ◽

William Boggess ◽

...

Keyword(s):

Sonic Hedgehog ◽

Cognitive Deficits ◽

The United States ◽

Glutamate Excitotoxicity ◽

Ionotropic Glutamate Receptors ◽

Chemical Signaling ◽

Shh Signaling ◽

Central Nervous System Damage ◽

Weight Drop ◽

Post Traumatic

Approximately 2 million individuals experience a traumatic brain injury (TBI) every year in the United States. Secondary injury begins within minutes after TBI, with alterations in cellular function and chemical signaling that contribute to excitotoxicity. Post-traumatic seizures (PTS) are experienced in an increasing number of TBI individuals that also display resistance to traditional anti-seizure medications (ASMs). Sonic hedgehog (Shh) is a signaling pathway that is upregulated following central nervous system damage in zebrafish and aids injury-induced regeneration. Using a modified Marmarou weight drop on adult zebrafish, we examined PTS following TBI and Shh modulation. We found that inhibiting Shh signaling by cyclopamine significantly increased PTS in TBI fish, prolonged the timeframe PTS was observed, and decreased survival across all TBI severities. Shh-inhibited TBI fish failed to respond to traditional ASMs, but were attenuated when treated with CNQX, which blocks ionotropic glutamate receptors. We found that the Smoothened agonist, purmorphamine, increased Eaat2a expression in undamaged brains compared to untreated controls, and purmorphamine treatment reduced glutamate excitotoxicity following TBI. Similarly, purmorphamine reduced PTS, edema, and cognitive deficits in TBI fish, while these pathologies were increased and/or prolonged in cyclopamine-treated TBI fish. However, the increased severity of TBI phenotypes with cyclopamine was reduced by cotreating fish with ceftriaxone, which induces Eaat2a expression. Collectively, these data suggest that Shh signaling induces Eaat2a expression and plays a role in regulating TBI-induced glutamate excitotoxicity and TBI sequelae.

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