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A key behavior observed during morphogenesis, wound healing, and cancer invasion is that of collective and coordinated cellular motion. Hence, understanding the different aspects of such coordinated migration is fundamental for describing and treating cancer and other pathological defects. In general, individual cells exert forces on their environment in order to move, and collective motion is coordinated by cell–cell adhesion‐based forces. However, this notion ignores other mechanisms that encourage cellular movement, such as pressure differences. Here, using model tumors, it is found that increased pressure drove coordinated cellular motion independent of cell–cell adhesion by triggering cell swelling in a soft extracellular matrix (ECM). In the resulting phenotype, a rapid burst‐like stream of cervical cancer cells emerged from 3D aggregates embedded in soft collagen matrices (0.5 mg mL−1). This fluid‐like pushing mechanism, recorded within 8 h after embedding, shows high cell velocities and super‐diffusive motion. Because the swelling in this model system critically depends on integrin‐mediated cell–ECM adhesions and cellular contractility, the swelling is likely triggered by unsustained mechanotransduction, providing new evidence that pressure‐driven effects must be considered to more completely understand the mechanical forces involved in cell and tissue movement as well as invasion. [ABSTRACT FROM AUTHOR]

Abstract: The potential of 13 foodborne bacteria to attach and survival on strawberries and the antimicrobial activities of Hibiscus sabdariffa calyx extracts and chemical sanitizers against foodborne bacteria on strawberries were investigated. Strawberries were inoculated with thirteen foodborne bacteria: Listeria monocytogenes, Shigella flexneri, Staphylococcus aureus, Salmonella Typhimurium, S. Typhi, S. Montevideo, Vibrio cholerae O1, and six pathotypes of Escherichia coli: O157:H7, Non‐O157:H7‐Shiga toxin‐producing, enteropathogenic, enterotoxigenic, enteroinvasive, and enteroaggregative. The antibacterial effects of four roselle calyx extracts (in water, methanol, acetone, and ethyl acetate), sodium hypochlorite, colloidal silver, and acetic acid against all pathogenic bacteria were evaluated on contaminated strawberries. All foodborne bacteria attached and survived on strawberries at least 15 days. Acetonic and methanolic roselle calyx extracts caused a greater reduction in the concentration (until 3.8‐log10 reduction in some cases) of all foodborne bacteria than the sodium hypochlorite, colloidal silver and acetic acid on contaminated strawberries. Practical applications: The strawberry is an important crop in United States, Spain, and Mexico. However, fresh strawberries have been associated with foodborne disease caused by E. coli O157:H7 and Salmonella. There is little information about the attachment and survival of foodborne bacteria on strawberries. A number of studies have shown that chemical agents used to eliminate pathogenic bacteria on fruits have a limited antimicrobial effect. Roselle calyx extracts are reported to have an antimicrobial effect. This study provides information about the attachment and survival of different foodborne bacteria on strawberries and information on the significant impact of dry roselle calyx extracts may be potentially useful in disinfection procedures of strawberries. [ABSTRACT FROM AUTHOR]