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Squamous cell carcinoma (SCC) of the tongue is associated with tobacco use, alcohol abuse, and human papillomavirus (HPV) infections. While clinical outcomes have recently improved for HPV‐positive patients in general, 50% of patients suffering from tongue cancer die within 5 years of being diagnosed. Flavonoids are secondary plant metabolites with a wide range of biological activities including antioxidant, anti‐inflammatory, and anticancer activities. Flavonoids have generated high interest as therapeutic agents owing to their low toxicity and their effects on a large variety of cancer cell types. In this literature review, we evaluate the actions of flavonoids on SCC of the tongue demonstrated in both in vivo and in vitro models.  相似文献   
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Aedes aegypti is among the best‐studied mosquitoes due to its critical role as a vector of human pathogens and ease of laboratory rearing. Until now, this species was thought to have originated in continental Africa, and subsequently colonized much of the world following the establishment of global trade routes. However, populations of this mosquito on the islands in the southwestern Indian Ocean (SWIO), where the species occurs with its nearest relatives referred to as the Aegypti Group, have received little study. We re‐evaluated the evolutionary history of Ae. aegypti and these relatives, using three data sets: nucleotide sequence data, 18,489 SNPs and 12 microsatellites. We found that: (a) the Aegypti Group diverged 16 MYA (95% HPD: 7–28 MYA) from its nearest African/Asian ancestor; (b) SWIO populations of Ae. aegypti are basal to continental African populations; (c) after diverging 7 MYA (95% HPD: 4–15 MYA) from its nearest formally described relative (Ae. mascarensis), Ae. aegypti moved to continental Africa less than 85,000 years ago, where it recently (<1,000 years ago) split into two recognized subspecies Ae. aegypti formosus and a human commensal, Ae. aegypti aegypti; (d) the Madagascar samples form a clade more distant from all other Ae. aegypti than the named species Ae. mascarensis, implying that Madagascar may harbour a new cryptic species; and (e) there is evidence of introgression between Ae. mascarensis and Ae. aegypti on Réunion, and between the two subspecies elsewhere in the SWIO, a likely consequence of recent introductions of domestic Ae. aegypti aegypti from Asia.  相似文献   
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It is unclear how historical adaptation versus maladaptation in a prior environment affects population evolvability in a novel habitat. Prior work showed that vesicular stomatitis virus (VSV) populations evolved at constant 37°C improved in cellular infection at both 29°C and 37°C; in contrast, those evolved under random changing temperatures between 29°C and 37°C failed to improve. Here, we tested whether prior evolution affected the rate of adaptation at the thermal‐niche edge: 40°C. After 40 virus generations in the new environment, we observed that populations historically evolved at random temperatures showed greater adaptability. Deep sequencing revealed that most of the newly evolved mutations were de novo. Also, two novel evolved mutations in the VSV glycoprotein and replicase genes tended to co‐occur in the populations previously evolved at constant 37°C, whereas this parallelism was not seen in populations with prior random temperature evolution. These results suggest that prior adaptation under constant versus random temperatures constrained the mutation landscape that could improve fitness in the novel 40°C environment, perhaps owing to differing epistatic effects of new mutations entering genetic architectures that earlier diverged. We concluded that RNA viruses maladapted to their previous environment could “leapfrog” over counterparts of higher fitness, to achieve faster adaptability in a novel environment.  相似文献   
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International Journal of Peptide Research and Therapeutics - Gardnerella vaginalis produces vaginolysin (VLY), a cholesterol-dependent cytolysin, responsible of the cellular lysis and epithelial...  相似文献   
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