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The control of sourgrass (Digitaria insularis (L.) Fedde) is a challenge in soybean culture, and pre-emergent herbicides appear as a management option. The objective of this work was to evaluate the control of sourgrass using pre-emergent herbicides positioned in different water regimes and amounts of straw. The experiment was carried out in a greenhouse with a completely randomized design in a 6 x 3 factorial scheme, in the first factor the water regimes were allocated and in the second the pre-emergent herbicides (diclosulam (29.4 gia ha-1); flumioxazin + imazethapyr (50 + 106 gia ha-1) and diuron + sulfentrazone (420 + 210 gia ha-1)) these factors were isolated for the amounts of corn straw + Brachiaria ruziziensis (0 and 3 t ha-1). When applied directly to the soil and on straw, diclosulam showed the lowest percentages of control in all water regimes with the first rain of 5 mm and the second of 20 mm. Diuron + sulfentrazone and flumioxazin + imazethapyr did not present significant differences in water regimes, adequately controlling the sourgrass. The effectiveness of diclosulam was influenced by drought intervals after application, diuron + sulfentrazone and flumioxazin + imazethapyr showed an efficient control of sourgrass in all treatments. O controle do capim-amargoso (Digitaria insularis (L.) Fedde) é um desafio na cultura da soja, e os herbicidas pré-emergentes surgem como opção de manejo. O objetivo desse trabalho foi avaliar o controle do capim-amargoso através de herbicidas pré-emergentes posicionados em diferentes regimes hídricos e quantidades de palha. O experimento foi realizado em casa de vegetação com delineamento experimental inteiramente casualizado em esquema fatorial 6 x 3, no primeiro fator alocou-se os regimes hídricos e no segundo os herbicidas pré-emergentes (diclosulam (29,4 g.i.a ha-1); flumioxazin + imazethapyr (50 + 106 g.i.a ha-1) e diuron + sulfentrazone (420 + 210 g.i.a ha-1)) esses fatores foram isolados para as quantidades de palha de milho + Brachiaria ruziziensis (0 e 3 t ha-1). Na aplicação diretamente no solo e sobre palha, o diclosulam apresentou as menores porcentagens de controle em todos os regimes hídricos com primeira chuva de 5 mm e segunda de 20mm. Já diuron + sulfentrazone e flumioxazin + imazethapyr não apresentaram diferenças significativas nos regimes hídricos controlando adequadamente o capim-amargoso. A eficácia do diclosulam sofreu influência dos intervalos de seca após a aplicação, diuron + sulfentrazone e flumioxazin + imazethapyr apresentaram um controle eficiente do capim-amargoso em todos os tratamentos.

The reservoirs for NDM-producing Enterobacterales are increasing, not only in hospitals, but also in the environment and in the community, challenging the therapeutic efficacy of carbapenems. We aimed to characterize an isolate of Escherichia coli harboring the blaNDM-1 gene recovered from the bloodstream of a penguin (Spheniscus magellanicus) in Southern Brazil. A total of 74 bacterial isolates recovered from arterial blood samples from dead birds were submitted to species identification and antibiotic susceptibility evaluation. One isolate presented resistance to carbapenems (E. coli 89PenNDM) and proved to harbor the blaNDM-1 gene by multiplex high-resolution melting real-time PCR (PCR-HRM). Conjugation experiments indicated that the blaNDM-1 was transmissible to E. coli J53. Whole genome sequencing (WGS) confirmed the presence of the blaNDM-1 gene in a conjugative plasmid (IncA/C2 plasmid) in both the E. coli 89PenNDM and its transconjugants. The isolate was classified as ST 156 and many other resistance genes (e.g., sul1, sul,2, strA, floR, tet(A)) were identified, all carried in the same IncA/C2 plasmid. This is the first report of blaNDM-1-producing E. coli isolated from a penguin in the Brazilian seacoast. The presence of a carbapenemase gene in wildlife animals is of concern as they may become reservoirs of multidrug-resistant bacteria and disseminate them to the environment.

The fungi are living organisms of great importance around agriculture, food industry, and the pharmaceutical industry. The usage of these microorganisms in agriculture is for the biocontrol of diseases in plants of commercial interest. Some yeasts can fight phytopathogens through secondary metabolites produced, inhibiting their development. Some species show positive results in the control of pathologies in different cultures. Yeasts have been used as biocontrol agents, and among them, a Lachancea (Kluyveromyces) thermotolerans, which is present in plants (such as grapes), soil and insects, can be adapted to different environments and, possibly perform biological control, although it is not known its mode of action. This work aimed to analyze and identify secondary metabolites used by the yeast L. thermotolerans CCMA 0763 isolated from commercial grapes in the Agricultural Microbiology Laboratory (Federal University of Lavras-MG/BR), using the analytical method of Ultra High-Efficiency Liquid Chromatography (UHPLC) (HRMS) and Tandem Mass Spectrometry (MS/MS). Four heterocyclic compounds of the Alkaloids class were identified, three (03) natural: 4-Hydroxyquinoline, Xanthine and Calistegine A3, and one (01) synthetic: Clausehainanine C. Therefore, these compounds can be tested against phytopathogenic microorganisms. Key words: Yeast, biological control, secondary metabolite, ultra high-efficiency liquid chromatography (UHPLC), mass spectrometry.

O alumínio (Al) presente nos solos ácidos reduz o potencial fisiológico de sementes e limita o crescimento plântulas de diversas espécies de interesse agronômico. Entretanto, informações quanto à toxicidade do Al em Arctium lappa L. (bardana, Asteraceae) são escassos. Objetivou-se nesse estudo avaliar o efeito do estresse por alumínio na germinação e no vigor de plântulas de A. lappa. Foram testadas cinco concentrações de sulfato de alumínio hidratado Al2(SO4)3·16H2O: 0 (controle), 5, 10, 15 e 20 mmol L-1. O teste de germinação foi feito em caixas do tipo Gerbox (sobre papel – SP) e em rolo papel – RP, utilizando papel germitest® umedecidos 2,5 vezes seu peso seco. As sementes foram mantidas em câmaras de B.O.D, sob 20-30ºC e luz branca constante. O potencial fisiológico das sementes e vigor de plântulas foi avaliado por meio dos testes de primeira contagem de germinação (4 dias), germinação (7 dias) e comprimento de plântulas. Observamos redução da germinação conforme aumento das concentração de Al em substrato SP. Os menores comprimentos da parte aérea das plântulas ocorreram com 20 mmol L-1 de Al e no substrato SP. Ocorreu inibição radicular das plântulas conforme aumento das concentração de Al nos dois substratos, especialmente no SP. O estresse por alumínio e substrato SP afetou negativamente a germinação de sementes e vigor das plântulas de A. lappa.

As espécies do gênero Pseudoplatystoma e seus híbridos vêm se consolidando no mercado aquícola brasileiro, devido ao alto valor comercial e a sua boa aceitação no mercado, basicamente em função de uma carne com sabor pouco acentuado, textura firme, coloração clara, baixo teor de gordura e ausência de espinhas intramusculares. Entretanto, a falta de informações relacionadas aos aspectos da sua nutricão dificulta a confecção de dietas comerciais adequadas. A literatura apresenta valores de digestibilidade de nutrientes e energia para uma pequena gama de ingredientes e a exigência protéica e energética com valores variando em uma amplitude ainda muito alta. Entretanto, como esta revisão aponta, há a necessidade de mais estudos acerca da sua nutrição e alimentação. A medida que os estudos avançam e o conhecimento cresce, a fabricação de rações comerciais a partir de dados espécie específicos pode proporcinar um aumento da produtividade da criação, bem como um maior rendimento financeiro para o pisciultor.

The inner-envelope K+ EFFLUX ANTIPORTERS (KEA) 1 and 2 are critical for chloroplast development, ion homeostasis, and photosynthesis. However, the mechanisms by which changes in ion flux across the envelope affect organelle biogenesis remained elusive. Chloroplast development requires intricate coordination between the nuclear genome and the plastome. Many mutants compromised in plastid gene expression (PGE) display a virescent phenotype, that is delayed greening. The phenotypic appearance of Arabidopsis thaliana kea1 kea2 double mutants fulfills this criterion, yet a link to PGE has not been explored. Here, we show that a simultaneous loss of KEA1 and KEA2 results in maturation defects of the plastid ribosomal RNAs. This may be caused by secondary structure changes of rRNA transcripts and concomitant reduced binding of RNA-processing proteins, which we documented in the presence of skewed ion homeostasis in kea1 kea2. Consequently, protein synthesis and steady-state levels of plastome-encoded proteins remain low in mutants. Disturbance in PGE and other signs of plastid malfunction activate GENOMES UNCOUPLED 1-dependent retrograde signaling in kea1 kea2, resulting in a dramatic downregulation of GOLDEN2-LIKE transcription factors to halt expression of photosynthesis-associated nuclear-encoded genes (PhANGs). PhANG suppression delays the development of fully photosynthesizing kea1 kea2 chloroplasts, probably to avoid progressing photo-oxidative damage. Overall, our results reveal that KEA1/KEA2 function impacts plastid development via effects on RNA-metabolism and PGE.

Intersex has been reported regularly in wild populations of gonochoristic fish. The authors investigated the possible feminization of seahorses in a population of Hippocampus reidi in Brazil, as well as report a case of a brood pouch reduction after reproductive stimuli. The female seahorses of this population showed two kinds of morphological anomalies. The proportion of the animals affected in the study population was consistent and was uncorrelated with the sex ratio. The study indicates the changes in the sexual profile of the individual.

O objetivo do presente trabalho foi avaliar a criação da tilápia do Nilo (Oreochromis niloticus), jundiá (Rhamdia quelen) e curimba (Prochilodus lineatus) em sistema de policultivo em tanque de PVC dentro de estufa plástica. Foi realizado no Laboratório de Tecnologia em Aquicultura (LATAq) Universidade Federal do Paraná Campus Avançado de Jandaia do Sul (UFPR), durante um período de 152 dias entre os meses de dezembro e maio. Foram utilizados 182 peixes, sendo 64 tilápias de 50±5g, 116 jundiás de 15±3g e 02 curimbas de 290±20g em um tanque 27m³. Foram utilizadas rações comerciais extrusadas com 28% proteína bruta. Os parâmetros da água: temperatura, oxigênio dissolvido, pH e nitrogênio amoniacal, foram mensurados durante todo período experimental. Ao final do período foi avaliado o desempenho zootécnico: peso final; ganho de peso; ganho de peso diário; conversão alimentar aparente; rendimento de carcaça; rendimento de filé; sobrevivência e morfometria de comprimento total e comprimento padrão. Ao final do período experimental a produção total de peixes foi de 46,14Kg (1,43kg/m3 ou 14.830 kg/ha) com uma conversão alimentar aparente de 1,66, com a água apresentando uma temperatura média de xxoC durante o período. Portanto, conclui-se que a produção e produtividade deste tipo de sistema apresentam valores interessantes do ponto de vista produtivo levando-se em consideração o tempo de criação e a temperatura média da água, visto que, não são distintos do que se atinge em criação comercial, assim, oferecendo um bom potencial para a sua utilização.

Habitat selection in certain species may vary according to context and environmental conditions. Sexual differences regarding habitat use have been reported for several species, such as mammals, birds and fish, and have been explained by protection and food resource contexts. This issue is not well studied in seahorses, but it may provide useful data for the management of threatened species. The Longsnout Seahorse has recently been considered near threatened, but many gaps regarding its habitat use are still noted. Seahorses display a particular breeding characteristic, in which males carry the embryos inside a breeding pouch, therefore leading to supposed careful selection of breeding habitats, avoiding predation risks and choosing habitats with high prey availability. In this context, this study aimed to verify differences in habitat selection between male and female Longsnout Seahorse Hippocampus reidi specimens along the coast of the state of Rio de Janeiro. This study took place at 11 sites along the Rio de Janeiro coastline, in southeastern Brazil. Random belt transects (20x5m) were assessed, searching for seahorses and their holdfasts. Random quadrats (50x50cm) divided into 100 cells/each were placed along the transects and benthic cover was counted, in order to establish substrate availability. Results suggested that males select fewer substrate types than females, but no statistical difference was detected. Both male and female H. reidi specimens select mostly Sargassum vulgare as a frequent habitat. The strong association of H. reidi to these seaweed beds suggests vulnerability concerning the degradation of this habitat.

Seahorses are commonly used in the aquarium trade and in seahorse-watching ecotourism in Brazil. Their manipulation and transportation may lead to significant stress, compromising their health. Ass...

The objective of this research is to evaluate the impact of soil management and localized irrigation techniques on water use efficiency in the cultivation of cauliflower. The treatments consisted of 4 different types of soil management: Direct seeding using crotalaria and brachiaria cover crops, a treatment used both in conjunction, and another that employed a conventional system. Two different irrigation techniques were used: Surface and subsurface. The experimental design was completely random in a factorial arrangement (4x2) with four repetitions. Each experimental unit was composed of 20 cauliflower plants, with a density of 1.8 m between rows and 0.5 m between plants. The experiment was carried out in two stages; the first stage consisted of the establishment of the cover crops and the second stage of the planting of cauliflower cv. Avenger in the different treatments. The cover species were cut at ground level 108 days after they had been sown. The cauliflower seedlings were grown in a protected environment and transplanted after 21 days. Irrigation was managed through the use of tensiometry. Water use efficiency was the variable that was analyzed; the Tukey Test at 5% level of probability was applied to the data that was obtained. A combined use of crotalaria/brachiaria cover crops with subsurface drip irrigation is recommended; this was the combination that most efficiently saved water. Key words: Brassica oleracea cv. botrytis, Crotalaria ochroleuca, Brachiaria ruziziensis, soil management, irrigation.

O imazapic por apresentar longo efeito residual no solo pode ocasionar intoxicação visual em culturas sensíveis semeadas em rotação, além de representar riscos ecotoxicológicos em ambientes aquáticos. Diante disso, a fitorremediação é uma proposta inovadora como método alternativo para a remoção de poluentes orgânicos, sendo o sucesso da técnica dependente da seleção criteriosa de plantas com características favoráveis. O objetivo do estudo foi de identificar espécies de plantas tolerantes ao imazapic para potencial uso em programas de fitorremediação. Foram conduzidos oito experimentos em casa de vegetação climatizada com as espécies, Panicum maximum, Crotalaria juncea, Stylosanthes spp., Cajanus cajan, Dolichos lablab, Pennisetum glaucum, Mucuna aterrima, Raphanus sativus e cinco doses de imazapic (0; 58,33; 87,5; 175 e 350 g ha-1). Os tratamentos foram delineados em blocos ao acaso com quatro repetições. Aos 30 e 60 dias após a emergência das plantas foram avaliados os sintomas de intoxicação visual, altura e a massa seca das plantas, determinada ao término do experimento. As espécies M. aterrima, C. cajan e D. lablab não apresentaram sintomas visuais de fitointoxicação. M. aterrima foi a que promoveu maior produção de massa seca quando cultivada como testemunha e a exposição ao imazapic pouco afetou essa característica. Nas espécies tolerantes, a redução da altura e massa seca exigiu doses maiores, embora os resultados não tenham sido significativos para D. lablab e C. cajan. Entre essas espécies, M. aterrima se destacou pela alta produção de biomassa, sendo promissora na fitorremediação de sítios com resíduos do imazapic.

* New plant functions in the exchange of greenhouse gases between ecosystems and atmosphere have recently been discovered. We tested whether photosynthetic activity has an effect on N2O emission rates from incubated plant–soil systems. * Two laboratory experiments were performed. One to unravel possible effect of photosynthetic activity on the net N2O ecosystem exchange for two species (beech and ash saplings). The other to account for possible effects from rhizosphere and aboveground plant parts separately (ash sapling only). * Total N2O emissions from both plant and plant–soil systems were significantly lower under light than in darkness (31%–65%). The photosynthetic effect only applied to the aboveground plant parts. * Underlying processes have now to be unraveled to improve our understanding of ecosystem functioning. This will improve modeling and budgeting of greenhouse gas exchanges between ecosystems and the atmosphere.

Summary The mTERF gene family encodes for nucleic acid binding proteins that are predicted to regulate organellar gene expression in eukaryotes. Despite the implication of this gene family in plant development and response to abiotic stresses, a precise molecular function was assigned to only a handful number of its c. 30 members in plants.Using a reverse genetics approach in Arabidopsis thaliana and combining molecular and biochemical techniques, we revealed new functions for the chloroplast mTERF protein, MDA1.We demonstrated that MDA1 associates in vivo with components of the plastid‐encoded RNA polymerase and transcriptional active chromosome complexes. MDA1 protein binds in vivo and in vitro with specificity to 27‐bp DNA sequences near the 5′‐end of psbE and ndhA chloroplast genes to stimulate their transcription, and additionally promotes the stabilization of the 5′‐ends of processed psbE and ndhA messenger (m)RNAs. Finally, we provided evidence that MDA1 function in gene transcription likely coordinates RNA folding and the action of chloroplast RNA‐binding proteins on mRNA stabilization.Our results provide examples for the unexpected implication of DNA binding proteins and gene transcription in the regulation of mRNA stability in chloroplasts, blurring the boundaries between DNA and RNA metabolism in this organelle.

Lower limb malalignment in the frontal plane is one of the major causes of developing knee osteoarthritis. Growing children can be treated by temporary hemiepiphysiodesis when diagnosed with lower limb malalignment.Is there a difference between medial or lateral knee contact force (KCF) before (PRE) and after (POST) hemiepiphysiodesis in patients with valgus malalignment and compared to a typically developed control group (TD)? Does a linear relationship exist between the static radiographic mechanical axis angle and dynamic medial/lateral KCF?In this prospective study, an OpenSim full body model with an adapted knee joint was used to calculate KCFs in the stance phase of 16 children with diagnosed genu valgum and 16 age- and sex-matched TDs. SPM was applied to compare KCFs before and after guided growth and to test a linear relationship between the mechanical axis angle and KCFs.After the intervention, POST revealed a significantly increased medial KCF (p 0.001, 4-97 % of stance) and decreased lateral KCF (p 0.001, 6-98 %) compared to PRE. Comparing POST with TD, short phases with a significant difference were found (medial: p = 0.039, 84-88 %; lateral: p = 0.019, 3-11 %). The static mechanical axis angle showed a longer phase of a significant relation to KCFs for POST compared to PRE.This study showed that temporary hemiepiphysiodesis in patients with valgus malalignment reduces the loading in the lateral compartment of the knee and thus the risk of developing osteoarthritis in this compartment. The determination of dynamic KCFs can be clinically relevant for the treatment of lower limb malalignment, especially for decision making before surgery, when compensatory mechanisms may play an important role. Additionally, the static radiographic mechanical axis angle does not necessarily represent the dynamic loading of the lateral knee compartment.

Recent advances in chronic toxoplasmosis understanding became the focus of discussion about behavioral abnormalities, which could be explained by cyst location and neuronal impairment in specific brain areas. Perineuronal nets (PNNs) are specialized extracellular matrices that surround the neuronal body and proximal dendrites and play key roles in neuronal circuitry maintenance and stabilization. Its impairment can lead to abnormal synaptic functioning with behavioral repercussions. In this context, we analyzed the impact of Toxoplasma gondii infection on neuronal integrity in the Corpus striatum of chronically infected mice. C57BL/6 and Balb/c female mice were infected with T. gondii ME49 cysts. Brain sections were submitted to immunohistochemistry with Wisteria floribunda agglutinin (WFA) for PNN labeling followed by quantification of tissue cyst and labeled neuronal cells 30 days after infection. Our results revealed that C57BL/6 exhibited a significant decrease in PNN-positive (WFA+) labeled neurons and an expressively higher number of tissue cysts than Balb/c mice. It was also possible to observe that the number of T. gondii tissue cysts and the number of WFA+ neurons were inversely correlated for C57BL/6-infected mice. However, no correlation was observed for Balb/c mice. These data suggest how the impact of parasite dissemination in the brain and host characteristics can influence neuronal integrity impairment during infection by decreasing WFA+ neurons. This might be a plausible pathway in which the presence of T. gondii contributes to behavioral changes in the infected host.

A 37-year-old butcher developed respiratory symptoms during sausage and chicken production in a large company. In addition to various spices, the enzyme transglutaminase was a possible cause. The lung function test showed mild partial reversible airway obstruction and severe bronchial hyperresponsiveness. The IgE test showed sensitizations to various spice mixtures, coriander (0.74 kU/L), and to the ImmunoCAP-bound transglutaminase preparation from the workplace (7.12 kU/L). The skin prick tests with this transglutaminase were also positive. In the immunoblot of this preparation, a 40-kD protein reacted with the patient’s IgE and was identified as transglutaminase from Streptomyces mobaraensis by inhibition experiments. This is the first case of a butcher with an allergy to transglutaminase. After moving to a small enterprise without enzyme use, his symptoms improved. Sensitization and the course of the symptoms indicate a dominant role of transglutaminase in the patient’s allergic asthma.

O objetivo do presente trabalho foi avaliar o sistema alternado de producao da tilapia do Nilo e jundia quanto a qualidade e rendimento dos seus produtos finais. Os peixes foram produzidos em um sistema alternado de criacao, com as tilapias sendo engordadas durante os meses quentes e os jundias nos frios. Os peixes foram avaliados inteiros, file, residuo da filetagem e farinha deste residuo, quanto aos valores de materia seca, cinzas, proteina bruta e extrato etereo. Tambem foram avaliados quanto ao rendimento de carcaca com cabeca, rendimento de tronco limpo, rendimento de file e gordura visceral. Os parâmetros de avaliados foram submetidos a analise de variância e comparados pelo teste de Tukey. O jundia apresentou um rendimento de file e de tronco superior ao da tilapia do Nilo, da mesma forma um conteudo de gordura no file. Entretanto, a producao de farinha de residuo de file foi semelhante entre as duas especies, porem diferiram quanto a sua composicao. O sistema de producao da tilapia do Nilo e do jundia, de maneira alternada, nao proporcionou nenhuma evidencia de impacto na qualidade e rendimento dos produtos finais, sejam eles de alto valor agregado ou subprodutos. Desta forma, a utilizacao do jundia, como especie em crescimento no periodo frio, possibilita agregar ganhos ao produtor, melhorando a sustentabilidade desta cadeia no Sul do Brasil.

O presente trabalho objetivou determinar os melhores horarios e frequencias de alimentacao para alevinos de pacama ( Lophiosilurus alexandri ) com base no desempenho, sobrevivencia e parâmetros de carcaca. Foram utilizados 160 alevinos de pacama, com peso vivo medio de 2,7 ± 0,01g, distribuidos em um delineamento inteiramente casualizado, com quatro tratamentos e cinco repeticoes, num periodo de 30 dias. Os tratamentos constituiram-se da variacao da frequencia de arracoamento, com uma alimentacao matutina, uma alimentacao vespertina, duas alimentacoes diarias e tres alimentacoes diarias. Os parâmetros de peso final, ganho de peso, ganho de peso diario, sobrevivencia, comprimento total, altura, comprimento da cabeca, rendimento de carcaca e rendimento de carcaca sem cabeca dos alevinos nao apresentaram diferenca significativa (P>0,05) entre os tratamentos. A biomassa dos tanques foi maior (P

In this study we characterized the genetic environment of blaCTX-M and blaCMY-2 genes carried by 46 Escherichia coli isolates obtained from 20 chicken carcasses produced by five different brands in...

Microbially contaminated metal-working fluid (MWF) can cause respiratory symptoms in exposed workers in the form of exogenous allergic alveolitis/hypersensitivity pneumonitis (HP). The diagnosis of HP is based, among others, on the identification of the culprit and the detection of corresponding specific IgG antibodies (sIgG) in the patient’s serum. Commercial antigen tools for the detection of these HP triggers are rarely available; therefore, antigens from contaminated MWF workplace samples were isolated exemplarily for diagnosis of a suspected HP case. Various MWF-specific bacteria were identified in the workplace samples, including Pseudomonas oleovorans, Pseudomonas alcaliphila, Pseudomonas spec., Paenibacillus glucanolyticus, and Corynebacterium amycolatum. The sIgG antigen binding, detected by ImmunoCAP system against MWF antigens from workplace samples and against the identified bacterial antigens, was much stronger in the patient serum compared to selected reference sera. The highest sIgG concentrations in the patient’s serum could be determined against Pseudomonas antigens. Inhibition tests showed cross-reactions of MWF and Pseudomonas antigens, whereby the Pseudomonas antigens cross-reacted less with each other. For in-vitro diagnosis in case of suspected HP caused by contaminated MWF, workplace-related antigens are now available.

Background β2-adrenergic receptor (β2-AR) stimulation activates the G protein/cAMP pathway, which is opposed by the GRK2/β-arrestin 2 pathway. The latter is undesirable in the treatment of respiratory diseases. Hypothesis/Purpose EA 575® is capable of mediating a biased β2-adrenergic signaling pathway. Methods The impact of the ivy leaves dry extract EA 575® on β2-adrenergic signaling was tested in a dynamic mass redistribution assay in HEK wild-type and in HEK β-arrestin knock-out cells. cAMP formation and recruitment of β-arrestin 2 were investigated using GloSensor™ and PathHunter® assays, respectively. NFκB transcriptional activity was determined in both HEK wild-type as well as HEK β-arrestin knock-out cells. Results EA 575® inhibits the recruitment of β-arrestin 2 and thereby enhances G protein/cAMP signaling under β2-stimulating conditions, as evidenced by a corresponding increase in cAMP formation. While β2-AR-mediated inhibition of NFκB transcriptional activity is β-arrestin-dependent, EA 575® leads to significant inhibition of NFκB transcriptional activity in β-arrestin knock-out cells and thus via a β-arrestin-independent signaling pathway. Conclusion EA 575® is the first active phytopharmaceutical ingredient for which biased β2-adrenergic activation has been described. This shift towards G protein/cAMP signaling provides the molecular basis for the clinically proven efficacy of EA 575® in the treatment of lower respiratory tract diseases. In this light, EA 575® could potentially reduce β-arrestin-mediated adverse effects in new combinatorial therapeutic approaches.

CTP synthases (CTPS) comprise a protein family of the five members CTPS1-CTPS5 in Arabidopsis, all located in the cytosol. Specifically, downregulation of CTPS2 by amiRNA technology results in plants with defects in chlorophyll accumulation and photosynthetic performance early in development. CTP and its deoxy form dCTP are present at low levels in developing seedlings. Thus, under conditions of fast proliferation, the synthesis of CTP (dCTP) can become a limiting factor for RNA and DNA synthesis. The higher sensitivity of ami-CTPS2 lines toward the DNA-Gyrase inhibitor ciprofloxacin, together with reduced plastid DNA copy number and 16S and 23S chloroplast ribosomal RNA support this view. High expression and proposed beneficial biochemical features render CTPS2 the most important isoform for early seedling development. In addition, CTPS2 was identified as an essential enzyme in embryo development before, as knock-out mutants were embryo lethal. In line with this, ami-CTPS2 lines also exhibited reduced seed numbers per plant.

Thesine oculis(SIX) family of transcription factors are key regulators of developmental processes during embryogenesis. Members of this family control gene expression to promote self-renewal of progenitor cell populations and govern mechanisms of cell differentiation. When the function ofSIXgenes becomes disrupted, distinct congenital defects develops both in animal models and humans. In addition to the embryonic setting, members of the SIX family have been found to be critical regulators of tumorigenesis, promoting cell proliferation, epithelial-to-mesenchymal transition, and metastasis. Research in both the fields of developmental biology and cancer research have provided an extensive understanding of SIX family transcription factor functions. Here we review recent progress in elucidating the role ofSIXfamily genes in congenital disease as well as in the promotion of cancer. Common themes arise when comparing SIX transcription factor function during embryonic and cancer development. We highlight the complementary nature of these two fields and how knowledge in one area can open new aspects of experimentation in the other.

Texture softening of pickled cucumbers does not meet consumers’ quality expectations and leads to economic losses. The factor(s) triggering this phenomenon is still unknown. We investigated the importance of plant viruses such as Cucumber green mottle mosaic tobamovirus (CGMMV) and Zucchini yellow mosaic potyvirus (ZYMV) in the context of softening of pickles. Cucumber plants (Cucumis sativus) were infected by mechanical inoculation, grown under greenhouse conditions and tested positive for the viral infection by ELISA. The severity of virus infection was reflected in yield and symptom expression. Histological and morphological alterations were observed. All fruits were pasteurized, separately stored in jars and subjected to texture measurements after four, six and 12 months. CGMMV-infections were asymptomatic or caused mild symptoms on leaves and fruit, and texture quality was comparable to control. At the same time, fruits of ZYMV-infected plants showed severe symptoms like deformations and discoloration, as well as a reduction in firmness and crunchiness after pasteurization. In addition, histological alterations were detected in such fruits, possibly causing textural changes. We conclude that plant viruses could have a considerable influence on the firmness and crunchiness of pickled cucumbers after pasteurization. It is possible that the severity of symptom expression has an influence on texture properties. European Agricultural Fund for Rural Development

Modifications in nucleic acids are present in all three domains of life. More than 170 distinct chemical modifications have been reported in cellular RNAs to date. Collectively termed as epitranscriptome, these RNA modifications are often dynamic and involve distinct regulatory proteins that install, remove, and interpret these marks in a site-specific manner. Covalent nucleotide modifications-such as methylations at diverse positions in the bases, polyuridylation, and pseudouridylation and many others impact various events in the lifecycle of an RNA such as folding, localization, processing, stability, ribosome assembly, and translational processes and are thus crucial regulators of the RNA metabolism. In plants, the nuclear/cytoplasmic epitranscriptome plays important roles in a wide range of biological processes, such as organ development, viral infection, and physiological means. Notably, recent transcriptome-wide analyses have also revealed novel dynamic modifications not only in plant nuclear/cytoplasmic RNAs related to photosynthesis but especially in chloroplast mRNAs, suggesting important and hitherto undefined regulatory steps in plastid functions and gene expression. Here we report on the latest findings of known plastid RNA modifications and highlight their relevance for the post-transcriptional regulation of chloroplast gene expression and their role in controlling plant development, stress reactions, and acclimation processes.

This is the first detection and genomic analysis of an OXA-181-carbapenemase-producing E. coli in Brazil, from a traveler returning from Sub-Saharan Africa. The ST167 isolate carries blaOXA-181 inserted in an IncX3 plasmid. This report illustrates the potential role of travelers as silent vectors for dissemination of high-risk resistant clones.

Klebsiella pneumoniae is an important human pathogen, able to accumulate and disseminate a variety of antimicrobial resistance genes. Resistance to colistin, one of the last therapeutic options for multi-drug-resistant bacteria, has been reported increasingly. Colistin-resistant K. pneumoniae (ColRKp) emerged in two hospitals in Rio de Janeiro state, Brazil in 2016. The aim of this study was to investigate if these ColRKp isolates were clonally related when compared between hospitals, to identify the molecular mechanisms of colistin resistance, and to describe other antimicrobial resistance genes carried by isolates. Twenty-three isolates were successively recovered, and the whole-genome sequence was analysed for 10, each of a different pulsed-field gel electrophoresis (PFGE) type. Although some PFGE clusters were found, none of them included isolates from both hospitals. Half of the isolates were assigned to CC258, three to ST152 and two to ST15. One isolate was pandrug resistant, one was extensively drug resistant, and the others were multi-drug resistant. Colistin resistance was related to mutations in mgrB, pmrB, phoQ and crrB. Eleven new mutations were found in these genes, including two nucleotide deletions in mgrB. All isolates were carbapenem resistant, and seven were associated with carbapenemase carriage (blaKPC-2 in six isolates and blaOXA-370 in one isolate). All isolates had a blaCTX-M, and two had a 16S ribosomal RNA methyltransferase encoding gene (armA and rmtB). ColRKp were composed of epidemic clones, but cross-dissemination between hospitals was not detected. Colistin resistance emerged with several novel mutations amid highly resistant strains, further restricting the number of drugs available and leading to pandrug resistance.

The effects of a diet supplemented with 5% marine fish oil, 5% refined palm oil, 5% soybean oil, and a combination of the three on reproductive parameters of females Rhamdia quelen was investigated. Spawning was artificially induced to evaluate rates of fertilization, hatching and larvae normality. Fatty acid profiles of the diets, ovaries and oocytes were determined. A higher spawning rate (%) was observed for diets containing fish oil (78.65 ± 3.60) and palm oil (77.15 ± 3.97), followed by oil mix (65.46 ± 4.57). The diet containing soybean oil was associated with significantly lower fertilization (60.14 ± 5.66; P 0.05) were observed for all tested diets, whit 289.77 ± 23.90 (palm oil) until 323.31 ± 38.45 oocytes g -1 body weight (fish oil). The treatments were not shown to influence oocyte size, larval size or rate of larva deformity. Oocyte fatty acid composition was like that of gonads. Docosahexaenoic (DHA; C22:6 n-3) fatty acid was preferentially deposited in ovaries and oocytes. Ratios of n3/n6, DHA/EPA, EPA/ARA, did not affect the reproductive performance of females. Therefore, regarding female reproductive performance, the vegetable lipid sources tested are suitable for being used in R. quelen diet, and palm oil, in particular, is considered an excellent alternative to fish oil.

Objective: Alcoholic liver disease (ALD) is among the leading causes of death from liver disease. Among the factors involved in its pathogenesis are inflammation and increased intestinal permeabili...

Microalgae are major antioxidant producers and feed containing these substances is known to be beneficial. Microalgae cultivation is an alternative way to produce biodiesel and, after oil extraction, residual algal biomass (RAB) is obtained. The RAB was tested as an ingredient in fish feed production and its safety evaluation is important to prevent risks to fish health. This study aim was to evaluate, through biochemical and genetic biomarkers, the safety of RAB in catfish, Rhamdia quelen, feed. Acutodesmus obliquus microalgae RAB, cultivated in Chu medium, was used in feed formulation. A standard feed without RAB (0%) was produced, and three other feeds were enriched with RAB in 1, 2, and 3% proportion. Each feed kind was given to a 15 R. quelen fingerling group for 60 days. The evaluated biochemical biomarkers were superoxide dismutase (SOD) and catalase (CAT) activities, lipid peroxidation (LPO) in the liver, and acetilcolinesterase (AChE) activity in the brain and muscles. The genetic biomarkers analyzed were halo assay in erythrocytes, comet assay in erythrocytes, liver and brain, and piscine micronucleus. The SOD activity was increased in the 3% group; CAT activity and LPO levels were not different among the groups. In the comet assay, a significant decrease in DNA damage in erythrocytes (2 and 3%) and liver tissue (3%) was observed. In the brain, DNA damage was not observed. These results corroborate that as the RAB amount increased, the organisms showed a potential antioxidant effect, as the 3% RAB feed had the best results.

Given the role of oxidative stress in ulcerative colitis (UC) etiology, and the amount of lutein (a carotenoid with antioxidant properties) in the dry hydroalcoholic extract of Tagetes erecta flowers (DHETE), this study investigated the intestinal anti-inflammatory properties of DHETE in an animal model of UC. The amount of lutein in the extract was determined by 1H-nuclear magnetic resonance spectroscopy, and total phenols, radical scavenger capability, cytotoxicity, and effects on reactive oxygen species and nitric oxide production were evaluated in vitro. Experimental UC was established by adding 5% dextran sulfate sodium (DSS) to drinking water, with the effects of DHETE (30-300 mg/kg, once a day for 7 days) on the morphological (colon length and weight), clinical (disease activity index and body weight loss), microscopic (histological score and mucin levels), and biochemical parameters analyzed. The lutein concentration found in DHETE was 8.2%, and DHETE scavenged 2,2-diphenyl-1-picrylhydrazyl radicals at 1000 μg/mL The exposure of intestinal epithelial cells to DHETE did not change its viability but reduced reactive oxygen species and nitric oxide production after lipopolysaccharide stimulation. In vivo, DHETE (300 mg/kg) attenuated weight loss, disease activity index, colon shortening, and histopathological changes promoted by DSS intake. Moreover, DHETE increased mucin colonic staining. The treatment with DHETE decreased myeloperoxidase activity as well as tumor necrosis factor and interleukin-6 levels. The extract also increased reduced glutathione levels and catalase activity and normalized superoxide dismutase and glutathione-S-transferase activities. In conclusion, DHETE reduced colitis severity by attenuating inflammatory cytokine secretion and improved the endogenous antioxidant defense in DSS-induced UC in mice.

The plastoglobular protein PG18 plays an important role in thylakoid formation and its loss has a significant impact on photosynthesis. This emphasizes the general importance of plastoglobules in chloroplast biogenesis., Plastoglobules are lipoprotein particles that are found in different types of plastids. They contain a very specific and specialized set of lipids and proteins. Plastoglobules are highly dynamic in size and shape, and are therefore thought to participate in adaptation processes during either abiotic or biotic stresses or transitions between developmental stages. They are suggested to function in thylakoid biogenesis, isoprenoid metabolism, and chlorophyll degradation. While several plastoglobular proteins contain identifiable domains, others provide no structural clues to their function. In this study, we investigate the role of plastoglobular protein 18 (PG18), which is conserved from cyanobacteria to higher plants. Analysis of a PG18 loss-of-function mutant in Arabidopsis thaliana demonstrated that PG18 plays an important role in thylakoid formation; the loss of PG18 results in impaired accumulation, assembly, and function of thylakoid membrane complexes. Interestingly, the mutant accumulated less chlorophyll and carotenoids, whereas xanthophyll cycle pigments were increased. Accumulation of photosynthetic complexes is similarly affected in both a Synechocystis and an Arabidopsis PG18 mutant. However, the ultrastructure of cyanobacterial thylakoids is not compromised by the lack of PG18, probably due to its less complex architecture.

Invasive species cause ecological and economic impacts on invaded ecosystems, although the presence of native species hampers the propagation of invasive species due to biotic resistance. We tested the effects of grazing by the native channeled applesnail (Pomacea canaliculata (Lamarck, 1828)) over the invasive macrophyte Hydrilla verticillata (L. f.) Royle (water thyme) and the native macrophyte Egeria najas Planch to evaluate the potential of herbivory as a mechanism to resist invasion. Both macrophyte species were offered, individually and combined, as food resources to the snail to evaluate its feeding preference. The macrophyte energy content and stiffness were also measured. The results indicate a higher H. verticillata biomass consumption by P. canaliculata when this macrophyte was available both individually and combined with E. najas, suggesting that H. verticillata is more palatable to the snail, despite this macrophyte being stiffer than the native one. Therefore, P. canaliculata may offer resistance to H. verticillata invasion. The feeding preference and high rates of herbivory by this snail on H. verticillata likely are associated with the higher energy content of the invasive, compared with the native, macrophyte. Experiments combining different food availabilities and snail densities are necessary to evaluate the biological control capacity of P. canaliculata under different scenarios.

Small and low-cost family aquaculture tilapia (Oreochromis niloticus) production with regional commercial targets is currently common practice in continental production systems of many parts of the world. In the state of Rio de Janeiro, Brazil, fish are reared in natural ponds, with limited technology, using available water resources. Nutrition relies on pelleted feed, and production costs are minimized by adding untreated manure and other organic fertilizers directly into the water. The aim of this study was to describe antimicrobial resistance in gram-negative bacteria isolated from fish produced under these conditions in four watersheds of that state. Gram-negative aerobic bacteria isolated from fish bowel and gill samples were identified, and resistance phenotypes determined. Fecal and sediment samples were analysed for residual evidence of tetracycline, the most commonly used therapeutic drug in animal husbandry, and for the presence of tetracycline resistance genetic determinants. Gram-negative bacteria belonging to different genera were the majority of culturable bacteria obtained from these samples. Results revealed a high number of tetracycline, and to a lesser extent, chloramphenicol resistant P. shigelloides strains, by far the predominant isolated bacterial species. Tetracycline residues were detected in both, sediment and fish fecal samples, from all farms. Tetracycline resistance genetic determinants tet(A), tet(C), tet(D), tet(M) and tet(O) were detected in sediment and fecal samples, and tet(A), tet(D) and tet(B) were detected in P. shigelloides isolates. Chloramphenicol resistant P. shigelloides isolates carried the floR, catI and catII genetic determinants. These data suggest the putative role of P. shigelloides as a reservoir for antimicrobial resistance genes in traditional continental aquaculture reflecting the selective pressure imposed by a combination of varied and uncontrolled rearing practices.

Photosystem II (PSII) is a supramolecular complex containing over 30 protein subunits and a large set of cofactors, including various pigments and quinones as well as Mn, Ca, Cl, and Fe ions. Eukaryotic PSII complexes contain many subunits not found in their bacterial counterparts, including the proteins PsbP (PSII), PsbQ, PsbS, and PsbW, as well as the highly homologous, low-molecular-mass subunits PsbTn1 and PsbTn2 whose function is currently unknown. To determine the function of PsbTn1 and PsbTn2, we generated single and double psbTn1 and psbTn2 knockout mutants in Arabidopsis (Arabidopsis thaliana). Cross linking and reciprocal coimmunoprecipitation experiments revealed that PsbTn is a lumenal PSII protein situated next to the cytochrome b559 subunit PsbE. The removal of the PsbTn proteins decreased the oxygen evolution rate and PSII core phosphorylation level but increased the susceptibility of PSII to photoinhibition and the production of reactive oxygen species. The assembly and stability of PSII were unaffected, indicating that the deficiencies of the psbTn1 psbTn2 double mutants are due to structural changes. Double mutants exhibited a higher rate of nonphotochemical quenching of excited states than the wild type and single mutants, as well as slower state transition kinetics and a lower quantum yield of PSII when grown in the field. Based on these results, we propose that the main function of the PsbTn proteins is to enable PSII to acclimate to light shifts or intense illumination.

Individual responses, particularly based on personality, can have important consequences for individual fitness, based upon success in exploring new habitats, feeding on novel foods, and aggressiveness in competitive interactions. We conducted laboratory experiments to analyze individual responses to different artificial conditions that could suit specific male and female personalities in the endangered seahorse, Hippocampus reidi. Our experiments with H. reidi evaluated individual responses to a new habitat, novel objects, level of inactivity and social interactions. We demonstrate that approximately half of the seahorses have a bold personality, readily inspecting new habitats and objects and sporadically presenting social approaches. The remaining shy individuals had high levels of inactivity and did not check novelties in their habitats. Although we expected that males would have shyer personalities when compared with females, due to their ecological role in the provision of parental care, we found no statistical difference between the sexes in terms of these aspects of personality. The similar frequency of both types of personality in males and females suggests that these features may be balanced and evolutionarily stable in the sampled population.

The exposure to selective serotonin reuptake inhibitors (SSRIs) during development results in behavioural impairment in adulthood in humans and animal models. Indeed, serotonergic overexpression in early life leads to structural and functional changes in brain circuits that control cognition and emotion. However, the effects of developmental exposure to these substances on the behaviour of adolescent rats are conflicting and remain poorly characterised. We performed a behavioural screening to investigate the effects of postnatal exposure to fluoxetine on memory and behaviours related to anxiety, anhedonia, and depression, as well we evaluate the parvalbumin expression in hippocampus of juvenile (~PND45) female and male rats. Fluoxetine (daily 20 mg/kg s.c. injections from PND7-PND21)- or vehicle-treated adolescent rats went through several behavioural tasks (from PND 38 to PND52) and were subject to transcardial perfusion and brain removal for immunohistochemical analysis (PND53). We found that postnatal exposure to fluoxetine increased anxiety- and depression-like behaviours in the open field and sucrose preference and forced swimming tests, respectively. In addition, this treatment induced working memory and short-term (but not long-term) recognition memory impairments, and reduced parvalbumin-positive interneurons in the hippocampus. In addition, the results revealed developmental sex-dependent effects of fluoxetine postnatal treatment on adolescent rats' behaviour. These outcomes indicate that affective disorders and mnemonic alterations caused by SSRIs perinatal exposure can be present at adolescence.

Melatonin is a hormone related to circadian rhythms and has potential clinical applications. Our objectives were to verify the effect of melatonin on the liver of zebrafish exposed to fructose and evaluate the expression of appetite-related genes (leptin, ghrelin, and melanocortin receptor 4 [MC4R]). Animals were divided into three groups: control (CG

Made available in DSpace on 2022-04-29T08:30:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-07-01 BACKGROUND: Croton oil (CO) is used by dermatologists and plastic surgeons in deep chemical peels. It is mixed with phenol, water, and a soap in Baker-Gordon's or Hetter's formulas. There is controversy as to whether CO or phenol is the active agent in the dermal effect of deep chemical peels. OBJECTIVE: To better clarify the role of CO in deep peels, by identification of active compounds in commercially available CO in the United States and biological effects in vivo. MATERIALS AND METHODS: Liquid chromatography-tandem mass spectrometry on CO and a domestic pig model experiment using 3 different formulas: G1: 5% Septisol (SEP), G2: 1.6% croton oil in 35% phenol with 5% SEP, and G3: 35% phenol with 5% SEP. RESULTS: Liquid chromatography-tandem mass spectrometry indicated the presence of phorbol esters. G1 was null overall. Extent of the coagulative necrosis: G2 > G3. Vascular ectasia: G2 > G3. Inflammation pattern: intense neutrophilic inflammatory band in G2 versus mild, sparse, perivascular mononuclear cell infiltrate in G3. Neocollagenesis: pronounced in G2, negligible in G3. CONCLUSION: Coagulative necrosis of the epidermis, superficial fibroblasts, and vasculature can be attributed to the action of phenol. Phorbol esters on CO could be responsible for the dense deep acute inflammation and the distinctive neocollagenesis. Departments of Pharmaceutical Sciences Medicine Dentistry Laboratory of Research of SEBISA State University of Ponta Grossa Laboratory Fenn of Massachusetts Spectrometry Federal University of Paraná Department of Dermatology Warren Alpert Medical School of Brown University Department of Dermatology and Radiotherapy Sao Paulo State University (UNESP) Department of Dermatology and Radiotherapy Sao Paulo State University (UNESP)

The pore structure of soil is known to be dynamic at time scales ranging from seconds (e.g. compaction) to seasons (e.g. root growth, macro-faunal activity) and even decades to centuries (e.g. changes in organic matter content). Nevertheless, soil physical and hydraulic functions are generally treated as static properties in most soil-crop models. Some models account for seasonal variations in soil properties (e.g. bulk density) due to tillage loosening and post-tillage consolidation or soil sealing. However, no model can account for longer-term changes in soil structure due to biological agents and processes. The development of such a model remains a challenge due to the enormous complexity of the interactions in the soil-plant system. Here, we present a new concept for modelling soil structure evolution impacted by biological processes such as root growth and earthworm activity. In this preliminary test of the model, we compare simulations against field observations made at the Soil Structure Observatory (SSO) in Zürich, Switzerland, that was designed to provide information on soil structure recovery following a severe compaction event. In this simple application, we modelled changes in the pore size distribution in a bare soil treatment resulting from soil ingestion and egestion by earthworms and the loosening of compacted soil by casting at the soil surface. Following calibration, the model was able to reproduce the observed temporal development of total porosity, soil bulk density and pore size distribution during a four-year period following severe traffic compaction. The modelling approach presented here appears promising and could help support the development of cost-efficient strategies for sustainable soil management and the restoration of degraded soils.

Klebsiella pneumoniae causes a diversity of infections in both healthcare and community settings. This pathogen is showing an increased ability to accumulate antimicrobial resistance and virulence genes, making it a public health concern. Here we describe the whole-genome sequence characteristics of an ST15 colistin-resistant K. pneumoniae isolate obtained from a blood culture of a 79-year-old female patient admitted to a university hospital in Brazil. Kp14U04 was resistant to most clinically useful antimicrobial agents, remaining susceptible only to aminoglycosides and fosfomycin. The colistin resistance in this isolate was due to a ~1.3 kb deletion containing four genes, namely mgrB, yebO, yobH and the transcriptional regulator kdgR. The study isolate presented a variety of antimicrobial resistance genes, including the carbapenemase-encoding gene bla KPC-2, the extended-spectrum beta-lactamase (ESBL)-encoding gene bla SHV-28 and the beta-lactamase-encoding gene bla OXA-1. Additionally, Kp14U04 harboured a multiple stress resistance protein, efflux systems and regulators, heavy metal resistance and virulence genes, plasmids, prophage-related sequences and genomic islands. These features revealed the high potential of this isolate to resist antimicrobial therapy, survive in adverse environments, cause infections and overcome host defence mechanisms.

The mitochondrial transcription termination factor proteins are nuclear-encoded nucleic acid binders defined by degenerate tandem helical-repeats of ~30 amino acids. They are found in metazoans and plants where they localize to mitochondria or chloroplasts. In higher plants, the mTERF family comprises ~30 members and several of these have been linked to plant development and response to abiotic stress. However, knowledge of the molecular basis underlying these physiological effects is scarce. We show that the Arabidopsis mTERF9 protein promotes the accumulation of the 16S and 23S rRNAs in chloroplasts, and interacts predominantly with the 16S rRNA in vivo and in vitro. Furthermore, mTERF9 is found in large complexes containing ribosomes and polysomes in chloroplasts. The comprehensive analysis of mTERF9 in vivo protein interactome identified many subunits of the 70S ribosome whose assembly is compromised in the null mterf9 mutant, putative ribosome biogenesis factors and CPN60 chaperonins. Protein interaction assays in yeast revealed that mTERF9 directly interact with these proteins. Our data demonstrate that mTERF9 integrates protein-protein and protein-RNA interactions to promote chloroplast ribosomal assembly and translation. Besides extending our knowledge of mTERF functional repertoire in plants, these findings provide an important insight into the chloroplast ribosome biogenesis.

Predator–prey interactions are complex relationships between both participants. Although many food items are available in the environment for a frog, it can choose to feed on one item instead of another, depending on several aspects of the prey, such as size, availability, abundance, mobility, and palatability. In this study we compared the frequency of each food item we observed in stomachs of the frog Chiasmocleis leucosticta with the availability of leaf litter arthropods we collected at the same place and time that of the frogs through Ivlev's electivity index. We verified that the electivity for ants and mites as food items in the diet of the population from Reserva Florestal de Morro Grande is an actual preference. Chiasmocleis leucosticta seems to elect smaller sized genera, such as Solenopsis and Pheidole, and avoid bigger and more aggressive ants, such as Pachycondyla, Camponotus, and Odontomachus. Also, we suggest that for C. leucosticta or even for other Microhylidae there is reason to believe that alkaloids are obtained as part of the diet; related studies on the biochemistry of this family, genus, and species are encouraged.