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Although vaccines and antiviral drugs are available, influenza viruses continue to pose a significant threat to vulnerable populations globally. With the emergence of drug-resistant strains, there is a growing need for novel antiviral therapeutic approaches. We found that 18-hydroxyferruginol (1) and 18-oxoferruginol (2) isolated from Torreya nucifera exhibited strong anti-influenza activity, with 50% inhibitory concentration values of 13.6 and 18.3 μM against H1N1, 12.8 and 10.8 μM against H9N2, and 29.2 μM (only compound 2) against H3N2 in the post-treatment assay, respectively. During the viral replication stages, the two compounds demonstrated stronger inhibition of viral RNA and protein in the late stages (12–18 h) than in the early stages (3–6 h). Moreover, both compounds inhibited PI3K-Akt signaling, which participates in viral replication during the later stages of infection. The ERK signaling pathway is also related to viral replication and was substantially inhibited by the two compounds. In particular, the inhibition of PI3K-Akt signaling by these compounds inhibited viral replication by sabotaging influenza ribonucleoprotein nucleus-to-cytoplasm export. These data indicate that compounds 1 and 2 could potentially reduce viral RNA and viral protein levels by inhibiting the PI3K-Akt signaling pathway. Our results suggest that abietane diterpenoids isolated from T. nucifera may be potent antiviral candidates for new influenza therapies.

Rotavirus is the main causative agent of viral gastroenteritis among young animals worldwide. Currently, no clinically approved or effective antiviral drugs are available to combat rotavirus infections. Herein, we evaluated the anti-rotaviral activities of extracts and bavachin isolated from Psoralea corylifolia L. (Fabaceae) (P. corylifolia) against the bovine rotavirus G8P[7] and porcine rotavirus G5P[7] in vitro. Two assay strategies were performed: (1) a virucidal assay to reduce viral infectivity by virus neutralization and (2) a post-treatment assay to assess viral replication suppression. The results from the virucidal assay showed that the extracts and bavachin did not exert anti-rotaviral activities. In the follow-up analysis after treatment, bavachin exhibited robust antiviral efficacy, with 50% effective concentration (EC50) values of 10.6 μM (selectivity index [SI] = 2.38) against bovine rotavirus G8P[7] and 13.0 μM (SI = 1.94) against porcine rotavirus G5P[7]. Bavachin strongly suppressed viral RNA synthesis in the early (6 h) and late stages (18 h) after rotaviral infection. These findings strongly suggest that bavachin may have hindered the virions by effectively inhibiting the early stages of the virus replication cycle after rotaviral infection. Furthermore, confocal imaging showed that bavachin suppressed viral protein synthesis, notably that of the rotaviral protein (VP6). These results suggest that bavachin has strong antiviral activity against rotaviruses, inhibits viral replication, and is a candidate natural therapeutic drug targeting rotaviral infection. The utilization of bavachin isolated from P. corylifolia may contribute to decreased mortality rates, lower medication expenses, and enhanced economic viability in domestic farms.

Epigallocatechin 3-O-gallate (EGCG) is a predominant component in green tea with various health benefits. The 67 kDa laminin receptor (67LR) is a nonintegrin cell surface receptor that is overexpressed in various types of cancer; 67LR was identified a cell surface EGCG target that plays a pivotal role in tumor growth, metastasis, and resistance to chemotherapy. However, the plasma concentration of EGCG is limited, and its molecular mechanisms remain unelucidated in colon cancer. In this study, we found that the phosphodiesterase 5 (PDE5) inhibitor, vardenafil (VDN), potentiates EGCG-induced apoptotic cell death in colon cancer cells. The combination of EGCG and VDN induced apoptosis via activation of the endothelial nitric oxide synthase/cyclic guanosine monophosphate/protein kinase Cδ signaling pathway. In conclusion, the PDE5 inhibitor, VDN, may reduce the intracellular PDE5 enzyme activity that potentiates EGCG-induced apoptotic cell death in Caco-2 cells. These results suggest that PDE5 inhibitors can be used to elevate cGMP levels to induce 67LR-mediated, cancer-specific cell death. Therefore, EGCG may be employed as a therapeutic candidate for colon cancer.

Constructivism proposes that learners construct concepts based on prior knowledge and experiences. Numerous factors may lead to inadequate or improper concept construction, leading to misconceptions. This study provides a foundation for discussing literary misconceptions using discussions with 47 pre-service literature teachers on the origins of diverse misconceptions regarding the narrator and focalizer. The participants identified the narrator and focalizer in two fictional narratives and elucidated each concept. Thus, the causes and aspects of the misconceptions were identified. Misconceptions about the narrator and focalizer were found to involve four factors: over-contextualization of everyday experiences, misunderstanding of terms, transfer of misconceptions in textbooks, and miscategorization of prior knowledge. The transfer of misconceptions and miscategorization had the largest impact. Moreover, the aspects of misconceptions differed for each cause. Over-contextualization led to equating the narrator with the focalizer, and the transfer of misconceptions led to equating the narrator with the author. Miscategorization resulted in miscategorizing the narrator and focalizer as subordinate concepts of speech representation and point of view. Misunderstanding of terms interacted with other causes, leading to equating the narrator with the focalizer, as well as misclassifying them as speech representation. Based on these results, methods to overcome literary misconceptions at the curriculum, class, and teacher education levels were suggested.

Although vaccines have been developed for rotavirus infections, there is currently no effective therapeutic treatment. Therefore, this study aimed to evaluate the efficacy of 18-hydroxyferruginol (1) and 18-oxoferruginol (2) isolated from Torreya nucifera (T. nucifera) against bovine G8P[7] and porcine G5P[7] rotaviruses using two different assay strategies: 1) reduction of viral infectivity by neutralizing the virus (virucidal assay) and 2) inhibition of viral replication after infection (post-treatment assay). In the post-treatment assay, compounds 1 and 2 exhibited strong anti-rotavirus activity, with 50% effective concentration values of 24.7 μM (selectivity index; SI= 2.52) and 23.2 μM (SI= 1.75) against bovine G8P[7], 21.1 μM (SI= 2.95) and 22.6 μM (SI= 1.80) against porcine G5P[7], respectively. During viral replication, the two compounds demonstrated stronger inhibition of viral RNA synthesis in the late stages (18 h) than in the early stages (6 h). Compounds 1 and 2 also inhibited the synthesis of viral proteins such as VP6, as determined by immunofluorescence assay. Thus, it appears that compounds 1 and 2 isolated from T. nucifera possess strong antiviral activity against rotaviruses, inhibit viral replication, and may be developed into potential plant-derived therapeutic candidates against rotavirus infection. [ABSTRACT FROM AUTHOR]