The evolution of kink bands and kink band boundaries in a prealigned poly(styrene-bethylene propylene) lamellar diblock copolymer was investigated by applying steady shear at strains in the range of 1-10 strain units. Boundary morphologies were characterized using transmission electron microscopy. As the shear strain increases, both the kink bands and the lamellae within the kink bands rotate continuously toward the shearing direction, leading to a decrease in the tilt boundary angle and the kink band boundary angle. Simultaneously, the nature of the kink band boundary transforms. The chevron boundaries present at low strains, and thus large tilt angles, become omega boundaries as the strain increases to ∼3 strain units. At higher strains (∼5 strain units), the tilt angle further decreases, and the omega boundaries start to break, preferentially in the PS microdomains. Delamination of the PS microdomains was also observed at the highest strain amplitude (10 strain units), which was associated with the limited extent of entanglement across the PS microdomains.

Selenium (Se) is an essential element for human and animal health. Biogenic selenium nanoparticles (SeNPs) by microorganism possess unique physical and chemical properties and biological activities compared with inorganic Se and organic Se. The study was conducted to investigate the mainly biological activities of SeNPs by Lactobacillus casei ATCC 393 (L. casei 393). The results showed that L. casei 393 transformed sodium selenite to red SeNPs with the size of 50–80 nm, and accumulated them intracellularly. L. casei 393-SeNPs promoted the growth and proliferation of porcine intestinal epithelial cells (IPEC-J2), human colonic epithelial cells (NCM460), and human acute monocytic leukemia cell (THP-1)-derived macrophagocyte. L. casei 393-SeNPs significantly inhibited the growth of human liver tumor cell line-HepG2, and alleviated diquat-induced IPEC-J2 oxidative damage. Moreover, in vivo and in vitro experimental results showed that administration with L. casei 393-SeNPs protected against Enterotoxigenic Escherichia coli K88 (ETEC K88)-caused intestinal barrier dysfunction. ETEC K88 infection-associated oxidative stress (glutathione peroxidase activity, total superoxide dismutase activity, total antioxidant capacity, and malondialdehyde) was ameliorated in L. casei 393-SeNPs-treated mice. These findings suggest that L. casei 393-SeNPs with no cytotoxicity play a key role in maintaining intestinal epithelial integrity and intestinal microflora balance in response to oxidative stress and infection.

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This study aimed to investigate the pharmacology and anti-parasitic efficacy of albendazole–chitosan microspheres (ABZ-CS-MPs) for established intraperitoneal infections of Echinococcus multilocularis metacestodes in an experimental murine model. Male outbred Kunming mice infected with E. multilocularis Metacestodes were administered with three ABZ formulations, namely, ABZ-CS-MPs, Liposome–Albendazole (L-ABZ), and albendazole tablet (ABZ-T). Each of the ABZ formulations was given orally at three different doses of 37.5, 75, and 150mg/kg, three times a week for 12 weeks postinfection. After administering the drugs, we monitored the pharmacological performance and anti-parasitic efficacy of ABZ-CS-MPs compared with L-ABZ, and ABZ-T treated mice. ABZ-CS-MPs reduced the weight of tissues containing E. multilocularis metacestodes most effectively compared with the ABZ-T group and untreated controls. Metacestode grown was Highly suppressed during treatment with ABZ-CS-MPs. Significantly higher plasma levels of ABZ metabolites were measured in mice treated with ABZ-CS-MPs or L-ABZ compared with ABZ-T. In particular, enhanced ABZ-sulfoxide concentration profiles were observed in the mice given 150mg/kg of ABZ-CS-MPs, but not in the mice treated with L-ABZ. Histological examination showed that damages caused disorganization of both the germinal and laminated layers of liver hyatid cysts, demolishing their characteristic structures after treatment with ABZ-CS-MPs or L-ABZ. Over time, ABZ-CS-MPs treatment induced a shift from Th2-dominant to Th1-dominant immune response. CS-MPs As a new carrier exhibited improved absorption and increased bioavailability of ABZ in the treatment of E. multilocularis infections in mice.

We consider the dynamics of an isolated kink band within an otherwise well-aligned lamellar block copolymer (or other smectic A liquid crystal) subjected to a macroscopic shear flow. We find on geometrical grounds that normal relative motion of the tilt boundaries that delineate such a band, relative to the normal velocity of the fluid, can occur only if there is jump in the tangential component of the fluid velocity across the boundary. We show that such tangential slippage should be negligible for well-developed bands with narrow boundaries. These observations lead to a simple description of the evolution of an idealized kink band, in which the kink bandwidth remains constant after the formation of narrow tilt boundaries, and the tilt boundaries rotate as material surfaces in a shear flow. The resulting prediction for the rate of rotation of the layers within such a band is confirmed by in situ small-angle X-ray scattering (SAXS)-steady shear experiments, which measure the evolution of the distribution of lamellar orientations within kink bands in a predominantly parallel poly(styrene-co-ethylenepropylene) diblock copolymer.