The zebrafish (
Danio rerio
) has been proposed as a low-cost and simple alternative to the use of higher vertebrates in laboratory research on novel compounds with antinociceptive potential. In this ...study, we tested adult zebrafish (
Danio rerio
) as an alternative behavioral model of formalin-induced nociception. We evaluated the nociceptive effect of 0.1% formalin (3 or 5 μL; intramuscularly i.m.), applied into the tail or lips, on locomotor activity, using as parameter the number of times the fish crossed the lines between the quadrants of a glass Petri dish during the neurogenic stage (0–5 min) and the inflammatory stage (15–30 min). The behavioral model was validated by testing the antinociceptive effect of morphine and indomethacin (standard analgesic drugs used in the formalin test of rodents). We also tested whether the effect of morphine could be modulated by naloxone, an opioid antagonist. The effect of morphine and indomethacin on zebrafish locomotor behavior was evaluated with the open field test. The white/black test was used to rule out the anxiolytic effect of 0.1% formalin injected into the tail on adult zebrafish. Formalin (0.1%; 3 and 5 μL injected into the tail) increased significantly the nociceptive behavior of the adult zebrafish in both stages (
p
< 0.001 vs. control). Morphine and indomethacin (both 0.2 mg/mL; 20 μL; intraperitoneally i.p.) significantly inhibited nociception induced with formalin (5 μL injected i.m. into the tail) in both stages (
p
< 0.001). Naloxone blocked the antinociceptive effect of morphine. No influence on locomotion was observed. Locally administered formalin (injected into the tail) induced nociception, but not anxiety. The results suggest that the adult zebrafish behavioral model is a feasible alternative to more conventional laboratory models used in research on novel compounds with antinociceptive potential.
Introdução: O treino do bacio (TB) ou controlo de esfíncteres é uma etapa importante no desenvolvimento infantil. Existem poucos estudos e diretrizes sobre esta temática e, da pesquisa bibliográfica ...efetuada, não há dados epidemiológicos nacionais. Este estudo pretende descrever o processo do TB numa amostra de crianças portuguesas, determinando variáveis biológicas, sociais e económicas envolvidas e métodos aplicados. Metodologia: Efetuado um estudo transversal, observacional e analítico, selecionando uma amostra de conveniência na consulta de saúde infantil e juvenil de três centros de saúde. Recolhemos os dados através de um questionário aos pais de crianças entre 18 e 42 meses (M). Excluímos patologias crónicas que interfiram na aquisição de controlo de esfíncteres, gémeos ou dados insuficientes. Resultados: Foram realizados inquéritos aos pais de 83 crianças com idades compreendidas entre 18M e 42M, das quais 24 não deram início ao TB. Das 59 restantes, 31 eram rapazes e a média de idades 31M desvio-padrão (DP)=9. A idade média de início e término do TB foi 22M (DP=7) e 27M (DP=7), respetivamente (mais cedo nas raparigas). Crianças do meio rural, filhos de mães empregadas e com escolaridade ≤ 5 anos iniciaram o TB mais cedo. No total, 20 completaram o TB, após uma duração em média de 3M (mediana 2M 0-16M). O grupo que iniciou mais cedo completou com menor idade o TB (p = 0,005); contudo, a duração até aquisição de controlo de esfíncteres foi maior (p = 0,046). Os métodos aplicados mais vezes pelos cuidadores foram reforço positivo e mostrar exemplos. Conclusões: A transição para TB apresenta grande variabilidade de fatores; nesta amostra, crianças do sexo feminino, filhos de mães empregadas e com menos instrução académica, a viver em meio rural, iniciaram o TB mais cedo. Existiu uma diferença estatisticamente significativa entre iniciar o TB com menor idade e a aquisição de controlo de esfíncteres mais precoce, mas também com maior duração do TB.
Apesar da epilepsia ser uma das doenças mais antigas do mundo esta ainda não possui uma cura definitiva, dado que a sua base celular e molecular não é ainda completamente conhecida. De facto, cerca ...de 30% dos pacientes epiléticos são refratários à terapia e a maioria destes sofre de epilepsia do lobo mesial temporal (MTLE). Apenas uma parte dos doentes refratários à terapêutica medicamentosa satisfazem os critérios para a remoção cirúrgica do tecido danificado como tratamento de último recurso, ficando os restantes doentes sujeitos a uma terapia anticonvulsiva pouco eficaz. Isto realça a necessidade de pesquisar novos alvos farmacológicos capazes de controlar as convulsões e/ou o processo epileptogénico.O glutamato e o ácido -aminobutírico (GABA) são neurotransmissores-chave no sistema nervoso central (CNS). O controlo minucioso da ação destes dois neurotransmissores é crucial para a manutenção da normalidade da transmissão sináptica no cérebro, já que o descontrolo entre a neurotransmissão glutamatérgica e GABAérgica tem sido considerado uma das causas da epilepsia. Nos últimos anos, a sinalização purinérgica tem surgido como um potencial alvo terapêutico para modular os níveis sinápticos destes neurotransmissores tendo em consideração que os níveis extracelulares do trifosfato de adenosina (ATP) e do seu metabolito, a adenosina, aumentam drasticamente no cérebro durante a atividade neuronal de elevada frequência e/ou lesões cerebrais. Por exemplo, a coabitação espacial e temporal destas duas purinas (ATP e adenosina) com os dois neurotransmissores, glutamato e GABA, tem sido frequentemente reportada durante crises convulsivas.Existem evidências sugerindo que durante as convulsões, a formação exagerada de adenosina no meio extracelular pode ter um papel pró-convulsivo através da ativação do recetor excitatório A2A, em consequência do desequilíbrio dos níveis extracelulares de glutamato e de GABA. Além disso, alguns trabalhos têm mostrado que o recetor A2A é preferencialmente ativado pela adenosina proveniente do catabolismo extracelular do ATP libertado, em que a enzima ecto-5’- nucleotidase/CD73 desempenha um papel limitante. Tendo em conta resultados anteriores do nosso grupo mostrando que o recetor A2A se encontra mais expresso nos astrócitos do hipocampo de doentes com MTLE, avaliámos a expressão da enzima ecto-5’-nucleotidase/CD73 e a sua relação com os recetores A2A em amostras de hipocampo de indivíduos controlo e de doentes com MTLE usando técnicas de Western blot e de imunofluorescência acoplada à microscopia confocal, respetivamente. Os resultados obtidos mostram que a ecto-5'-nucleotidase/CD73 está mais expressa (37 vezes) nos astrócitos de hipocampo de doentes com MTLE e que a mesma colocaliza, pelo menos parcialmente, com o recetor A2A da adenosina, sugerindo que a ecto-5'-nucleotidase/CD73 está idealmente posicionada para gerar adenosina a partir do ATP, promovendo assim a ativação imediata do recetor A2A.Resultados anteriores do grupo de investigação do Laboratório de Farmacologia e Neurobiologia do ICBAS mostraram que a ativação do recetor présináptico P2X7 pelo ATP favorece a libertação de GABA e glutamato a partir de terminais nervosos isolados (sinaptossomas) de córtex cerebral de ratazana na ausência de Ca2+. Apesar destas evidências, os mecanismos moleculares subjacentes a este efeito do ATP permanecem por esclarecer.
The objective of this study was to evaluate the humoral immune response and the innate response of goats immunized with attenuated vaccine against Corynebacterium pseudotuberculosis prepared from the ...strain 1002. One hundred goats were divided into 5 groups (n=20 animals/group). Each group was vaccinated as follows: G control: saline solution; G1 - 107 CFU/mL; G2 -107 CFU/mL re-vaccinated within 21 days; G3 - 106 CFU/mL; G4 - 106 CFU/mL revaccinated within 21 days. Blood samples were collected monthly over 12 months and serology was performed through indirect ELISA. In order to verify the innate response through the dosages of acute phase proteins (ceruloplasmin and haptoglobin), samples of five animals from each group were evaluated on days 0, 7, 14, 21, 28 days for the groups G1 and G3, and on days 0, 21, 28, 56 days for the groups G2 and G4. The results showed humoral response activation with the production of immunoglobulins above the cut-off point in all groups. The results showed that strain 1002 vaccine induced the antibody production by the goats' humoral immune system and that the increase in serum concentrations of haptoglobin and ceruloplasmin may be related of the innate immune response.
In agriculture, the control of fungal infections is essential to improve crop quality and productivity. This study describes the preparation and fungicidal activity evaluation of 12 glycerol ...derivatives bearing 1,2,3-triazole fragments. The derivatives were prepared from glycerol in four steps. The key step corresponded to the Cu(I)-catalyzed alkyne–azide cycloaddition (CuAAC) click reaction between the azide 4-(azidomethyl)-2,2-dimethyl-1,3-dioxolane (3) and different terminal alkynes (57–91% yield). The compounds were characterized by infrared spectroscopy, nuclear magnetic resonance (1H and 13C), and high-resolution mass spectrometry. The in vitro assessment of the compounds on Asperisporium caricae, that is, the etiological agent of papaya black spot, at 750 mg L–1 showed that the glycerol derivatives significantly inhibited conidial germination with different degrees of efficacy. The most active compound 4-(3-chlorophenyl)-1-((2,2-dimethyl-1,3-dioxolan-4-yl) methyl)-1H-1,2,3-triazole (4c) presented a 91.92% inhibition. In vivo assays revealed that 4c reduced the final severity (70.7%) and area under the disease severity progress curve of black spots on papaya fruits 10 days after inoculation. The glycerol-bearing 1,2,3-triazole derivatives also present agrochemical-likeness properties. Our in silico study using molecular docking calculations show that all triazole derivatives bind favorably to the sterol 14α-demethylase (CYP51) active site at the same region of the substrate lanosterol (LAN) and fungicide propiconazole (PRO). Thus, the mechanism of action of the compounds 4a–4l may be the same as the fungicide PRO, blocking the entrance/approximation of the LAN into the CYP51 active site by steric effects. The reported results point to the fact that the glycerol derivatives may represent a scaffold to be explored for the development of new chemical agents to control papaya black spot.
The Mediterranean diet, rich in olive oil, is beneficial, reducing the risk of cardiovascular diseases and cancer. Olive oil is mostly composed of the monounsaturated fatty acid omega-9. We showed ...omega-9 protects septic mice modulating lipid metabolism. Sepsis is initiated by the host response to infection with organ damage, increased plasma free fatty acids, high levels of cortisol, massive cytokine production, leukocyte activation, and endothelial dysfunction. We aimed to analyze the effect of omega-9 supplementation on corticosteroid unbalance, inflammation, bacterial elimination, and peroxisome proliferator-activated receptor (PPAR) gamma expression, an omega-9 receptor and inflammatory modulator. We treated mice for 14 days with omega-9 and induced sepsis by cecal ligation and puncture (CLP). We measured systemic corticosterone levels, cytokine production, leukocyte and bacterial counts in the peritoneum, and the expression of PPAR gamma in both liver and adipose tissues during experimental sepsis. We further studied omega-9 effects on leukocyte rolling in mouse cremaster muscle-inflamed postcapillary venules and in the cerebral microcirculation of septic mice. Here, we demonstrate that omega-9 treatment is associated with increased levels of the anti-inflammatory cytokine IL-10 and decreased levels of the proinflammatory cytokines TNF-α and IL-1β in peritoneal lavage fluid of mice with sepsis. Omega-9 treatment also decreased systemic corticosterone levels. Neutrophil migration from circulation to the peritoneal cavity and leukocyte rolling on the endothelium were decreased by omega-9 treatment. Omega-9 also decreased bacterial load in the peritoneal lavage and restored liver and adipose tissue PPAR gamma expression in septic animals. Our data suggest a beneficial anti-inflammatory role of omega-9 in sepsis, mitigating leukocyte rolling and leukocyte influx, balancing cytokine production, and controlling bacterial growth possibly through a PPAR gamma expression-dependent mechanism. The significant reduction of inflammation detected after omega-9 enteral injection can further contribute to the already known beneficial properties facilitated by unsaturated fatty acid-enriched diets.
This study was to evaluate the biological activity of the extract of Botryosphaeria fabicerciana isolated from leaves of Morus nigra. The volatile compounds from the crude extract were analysed by ...GC-MS which demonstrate that mellein and β-orcinaldehyde were are the major compounds. The best minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the extract was observed against Gram-positive bacteria, with a MIC of 15.6 μg/mL towards B. cereus and MIC of 62.5 μg/mL towards S. aureus and B. subtilis. MBC values of 31.25 μg/mL, 62.5 μg/mL, and 250 μg/mL were observed towards B. cereus, B. subtilis, and S. aureus, respectively. The cytotoxicity analyses showed CC50 of 115 μg/mL. The crude extract showed antioxidant activity by the DPPH, ABTS, and FRAP assays. Therefore, the extract of the endophytic fungus presented biotechnological potential as an antibacterial and antioxidant agent.
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