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Remote limb conditioning (RLC), performed by intermittent interruption of blood flow to a limb, triggers endogenous tolerance mechanisms and improves stroke outcomes. The underlying mechanism for the protective effect involves a shift of circulating monocytes to a Ly6CHigh proinflammatory subset in normal metabolic conditions. The current study investigates the effect of RLC on stroke outcomes in subjects with obesity, a vascular comorbidity. Compared to lean mice, obese stroke mice displayed significantly higher circulating monocytes (monocytosis), increased CD45High monocytes/macrophages infiltration to the injured brain, worse acute outcomes, and delayed recovery. Unlike lean mice, obese mice with RLC at 2 hours post-stroke failed to shift circulating monocytes to pro-inflammatory status and nullified RLC-induced functional benefit. The absence of the monocyte shift was also observed in splenocytes incubated with RLC serum from obese mice, while the shift was observed in the cultures with RLC serum from lean mice. These results showed that the alteration of monocytosis and subsets underlies negating RLC benefits in obese mice and suggest careful considerations of comorbidities at the time of RLC application for stroke therapy. [ABSTRACT FROM AUTHOR]

This study analyzed the effects of hygrothermal conditions on the single-lap shear strength of a carbon fiber/poly-ether-ketone-ketone (CF/PEKK) thermoplastic composite material fabricated by induction welding. Specimens were exposed to an 85 °C/85% environment using a temperature and humidity chamber to identify the effect of moisture on single-lap shear strength, while their moisture saturation was assessed through weight measurement. Single-lap shear strength tests were performed on the dried and saturated specimens at 25 °C and 100 °C to 180 °C at 20 °C intervals. At 160 °C, the strength of the CF/PEKK thermoplastic composites rapidly declined to 76% (dried specimens) and 78% (moist specimens). The fracture surfaces and failure modes were analyzed using scanning electron microscopy images, which confirmed an increase in the degraded areas and naked fibers at higher testing temperatures. In addition, it was found that exposure to a moist environment changes the failure mode from fiber bundles and fiber/matrix failure to naked fiber and matrix failure owing to the reduction in interfacial adhesion properties. The findings confirmed that hygrothermal conditions directly affect the degradation of the CF/PEKK thermoplastic composites and that a rapid reduction in the single-lap shear strength occurs above Tg. [ABSTRACT FROM AUTHOR]