Exploring Seaweed and Glycine Betaine Biostimulants for Enhanced Phenolic Content, Antioxidant Properties, and Gene Expression of Vitis vinifera cv. "Touriga Franca" Berries.

Climate change will pose a challenge for the winemaking sector worldwide, bringing progressively drier and warmer conditions and increasing the frequency and intensity of weather extremes. The short-term adaptation strategy of applying biostimulants through foliar application serves as a crucial measure in mitigating the detrimental effects of environmental stresses on grapevine yield and berry quality. The aim of this study was to evaluate the effect of foliar application of a seaweed-based biostimulant (A. nodosum-ANE) and glycine betaine (GB) on berry quality, phenolic compounds, and antioxidant activity and to elucidate their action on the secondary metabolism. A trial was installed in a commercial vineyard (cv. "Touriga Franca") in the Cima Corgo (Upper Corgo) sub-region of the Douro Demarcated Region, Portugal. A total of four foliar sprayings were performed during the growing season: at flowering, pea size, bunch closer, and veraison. There was a positive effect of GB in the berry quality traits. Both ANE and GB increased the synthesis of anthocyanins and other phenolics in berries and influenced the expression of genes related to the synthesis and transport of anthocyanins (CHS, F3H, UFGT, and GST). So, they have the potential to act as elicitors of the secondary metabolism, leading to improved grape quality, and also to set the foundation for sustainable agricultural practices in the long run.

Foliar application of nettle and Japanese knotweed extracts on Vitis vinifera: impact on phenylpropanoid biosynthesis and antioxidant activity during veraison and harvest of cv. Touriga Franca.

BACKGROUND: Plant-based extracts have been recently used as sustainable tools to improve biotic and abiotic stress tolerance and increase grape (Vitis vinifera L.) quality. However, knowledge about the effect of these extracts on secondary metabolism compounds, that are fundamental for grape and wine quality, is still scarce. In this study, a trial was installed in an experimental vineyard with the variety Touriga Franca located at University of Trás-os-Montes e Alto Douro, Baixo Corgo sub-region of the Douro Demarcated Region, Portugal in two growing seasons: 2019 and 2020. The aim was to evaluate the effect of foliar application of nettle (Urtica spp.) extract (NE) and Japanese knotweed (Reynoutria japonica) extract (JKE) on grapevines leaves and berries bioactive compounds contents and antioxidant activity, at veraison and harvest. RESULTS: The application of NE increased the total carotenoids in leaves and the total phenolics content and the antioxidant activity (ferric reducing antioxidant power, FRAP) in berries while JKE increased flavonoids content in leaves and the antioxidant activity (2,2-diphenyl-1-picrylhydrazyl, DPPH) in berries. CONCLUSION: These extracts seem to have a stimulatory effect on grapevine, enhancing bioactive compounds contents and antioxidant capacity and, consequently, the physiological performance of the plant and the quality of the berries. © 2024 Society of Chemical Industry.

Recombinant proteins of Plasmodium malariae merozoite surface protein 1 (PmMSP1): Testing immunogenicity in the BALB/c model and potential use as diagnostic tool.

BACKGROUND: Plasmodium malariae is the third most prevalent human malaria-causing species and has a patchy, but ample distribution in the world. Humans can host the parasite for years without presenting significant symptoms, turning its diagnosis and control into a difficult task. Here, we investigated the immunogenicity of recombinant proteins of P. malariae MSP1. METHODS: Five regions of PmMSP1 were expressed in Escherichia coli as GST-fusion proteins and immunized in BALB/c mice. The specificity, subtyping, and affinity of raised antibodies were evaluated by enzyme-linked immunosorbent assays. Cellular immune responses were analyzed by lymphoproliferation assays and cytokine levels produced by splenocytes were detected by cytometry. RESULTS: We found that N-terminal, central regions, and PmMSP119 are strongly immunogenic in mice. After three doses, the induced immune responses remained high for 70 days. While antibodies induced after immunization with N-terminal and central regions showed similar affinities to the target antigens, affinities of IgG against PmMSP119 were higher. All proteins induced similar antibody subclass patterns (predominantly IgG1, IgG2a, and IgG2b), characterizing a mixed Th1/Th2 response. Further, autologous stimulation of splenocytes from immunized mice led to the secretion of IL2 and IL4, independently of the antigen used. Importantly, IgG from P. malariae-exposed individuals reacted against PmMSP1 recombinant proteins with a high specificity. On the other hand, sera from P. vivax or P. falciparum-infected individuals did not react at all against recombinant PmMSP1 proteins. CONCLUSION: Recombinant PmMSP1 proteins are very useful diagnostic markers of P. malariae in epidemiological studies or in the differential diagnosis of malaria caused by this species. Immunization with recombinant PmMSP1 proteins resulted in a significant humoral immune response, which may turn them potential component candidates for a vaccine against P. malariae.

Tratamento da úlcera corneana experimental com membrana amniótica / Experimental corneal ulcer treated with amniotic membrane

Avaliar a evoluçäo da úlcera de córnea experimental tratada com enxerto de membrana amniótica (MA) homóloga. Métodos: Foram utilizados 18 coelhos, divididos em dois grupos experimentais: úlcera corneana (G1) e úlcera corneana tratada com enxerto de MA (G2). A ulceraçäo corneana foi induzida na córnea toda, com álcool absoluto e lâmina de bisturi. Os animais foram sacrificados em três momentos experimentais: 7 dias (M1), 15 dias (M2) e 30 dias (M3) após a induçäo da úlceraçäo. Os defeitos corneanos foram avaliados em fotodocumentaçäo por analizador de imagem Luzex-F e exames histopatológicos, comparando-se os resultados por meio de análise de variância. Resultados: O resultado do exame morfométrico mostrou desepitelizaçäo maior em G2 no M1; a opacidade corneana foi mais intensa na área central da córnea, sendo significativamente maior em G1 no M3. Os neovasos corneanos também foram mais instensos em G1. A avaliaçäo histopatológica revelou ulceraçäo epitelial em dois animais de G1 no M2 e em dois de G2 no M1; o edema estromal foi mais intenso em G1, assim como a presença de neovasos.

Laser de argônio no tratamento da triquíase e da distiquíase / Argon laser in the treatment of trichiasis and distichiasis

Objetivo: Avaliar a eficácia da fotocoagulaçäo com laser de argônio no tratamento da triquíase e distiquíase. Métodos: Estudo prospectivo de 77 pálpebras de portadores de triquíase e/ou distiquíase, tratados com fotocoagulaçäo dos folículos pilosos com '' Argon green laser '' (Nidek). Avaliou-se a idade, sexo, queixa apresentada, causa do mau posicionamento dos cílios, pálpebra acometida, tratamento efetuado (número de disparos efetuados em cada sessäo) e a evoluçäo após a aplicaçäo (cura ou reaplicaçäo). Os parâmetros utilizados foram: mira de 50 µm, 0.2 segundos de exposiçäo, potência inicial de 600mw e final de 1000mw. Os dados foram submetidos à análise estatística descritiva. Resultados: A pálpebra inferior (PI) foi mais acometida que a superior (PS) (89PI X 40PS) e a triquíase, mais comum que a distiquíase (89T X 44D). Apesar dos cílios distiquíaticos serem destruídos com menor número de aplicaçöes, a efetividade de destruiçäo de folículos pilosos foi maior na triquíase do que na distiquíase. A média dos disparos de laser na primeira aplicaçäo foi de 31 disparos, sendo que 75 por cento dos pacientes tiveram os cílios mal posicionados destruídos com 39 disparos. Com uma única sessäo de tratamemto 37.7 por cento dos pacientes se curaram e a porcentagem de cura com até cinco aplicaçöes foi de 98.7 por cento. Conclusäo: O laser de argônio é efetivo no tratamento da triquíase e da distiquíase.