β-Hexosaminidase, which is generally present in the lysosome, is essential for glycoprotein metabolism in the maintenance of cell homeostasis. In mast cells (MCs), large amounts of β-hexosaminidase are present in the granules as opposed to the lysosome, and the biological role of MC β-hexosaminidase has yet to be fully elucidated. Therefore, we investigated the biological role of β-hexosaminidase in MC granules. Bone marrow-derived MCs from C57BL/6 (BL/6-BMMC) or β-hexosaminidase gene–deficient (hexb−/−-BMMC) mice were transplanted into MC-deficient (WBB6F1/J-KitW/KitW-v [W/Wv]) mice to generate MC-reconstituted models. In asthma model experiments, no differences were observed in the symptoms of BL/6, W/Wv, BL/6-BMMC–reconstituted W/Wv, or hexb−/−-BMMC–reconstituted W/Wv mice. In Staphylococcus epidermidis experimental infection model experiments, the severity of symptoms and frequency of death were markedly higher in W/Wv and hexb−/−-BMMC–reconstituted W/Wv mice than in BL/6 and BL/6-BMMC–reconstituted W/Wv mice. The growth of S. epidermidis in an in vitro study was clearly inhibited by addition of BL/6-BMMC lysate, but not by addition of hexb−/−-BMMC lysate. Moreover, suppression of bacterial proliferation was completely recovered when bacteria were incubated with hexb−/−-BMMC lysate plus β-hexosaminidase. Transmission electron microscopy indicated that the cell wall of S. epidermidis was heavily degraded following coincubation of bacteria with BL/6-BMMC lysate, but not following coincubation with hexb−/−-BMMC lysate. These findings strongly suggest that MC granule β-hexosaminidase is crucial for defense against bacterial invasion, but is not involved in the allergic response. Our results also suggest that the bactericidal mechanism of β-hexosaminidase involves degradation of bacterial cell wall peptidoglycan.

b-Carotene is a member of the carotenoid family and is a red-orange pigment abundantly present in many vegetables and fruits. As an antioxidant, it eliminates excessive reactive oxygen species generated in the body. Accordingly, it has potential to be used in the pharmaceutical, food, and cosmetic industries. b-Carotene has a very low water solubility and low bioavailability; thus, there is a need to develop techniques to overcome these issues. In this study, we aimed to enhance the water solubility of b-carotene by using hot-melt technology, a type of solid dispersions technology. When preparing b-carotene solid dispersion using this method, suitable conditions for the emulsifiers and mixing ratios were investigated using water solubility as an index. Setting the weight ratio of bcarotene:polyvinylpyrrolidone:sucrose fatty acid ester to 10%:70%:20% resulted in the poorly-water soluble b-carotene showing improved water solubility (120 lg/mL). The physicochemical properties of the optimized b-carotene solid dispersion were analyzed using field emission scanning electron microscopy, differential scanning calorimetry, and powder X-ray diffraction. The solid dispersion was found to have an amorphous structure. The improved solubility observed for b-carotene in the solid dispersions developed in this work may make these dispersions useful as additives in foods or in nutraceutical formulations. Keywords b-Carotene Á Emulsifier Á Water solubility Á Hot-melt technology Á Solid dispersion Á Amorphous Kenji Ishimoto and Shohei Miki have contributed equally to this work.

Inconsistent oxygen isotopic values between contemporary secreted septa and outer shell walls in modern Nautilus AKANE OHNO, TSUZUMI MIYAJI AND RYOJI WANI Ohno, A., Miyaji, T. & Wani, R. 2014: Inconsistent oxygen isotopic values between contemporary secreted septa and outer shell walls in modern Nautilus. Lethaia, DOI: 10.1111/let.12109.The isotopic analyses of modern Nautilus pompilius from the Philippines demonstrated that the d 18O values are not always consistent between contemporary secreted septa and outer shell walls. This discrepancy is hypothesized as being related to the osmotic emptying through the siphuncle. The local osmosis in water at depths >240 m, which enhances salt concentration in siphuncular intercellular spaces, possibly makes the more positive salinity of extrapallial fluid in the interspace between the rear of soft parts and the newly forming septum, from which the calcium carbonate of the septum is precipitated. Therefore, the d 18O values of septa become more positive than those in the outer shell walls. Actually, the d 18O values of outer shell walls fit more reasonably the actual seawater temperature at the study area, than those of septa. Furthermore, the d 18O values are not constant even in a single septum with a discrepancy equivalent to~1-4°C of the estimated water temperature. These facts suggest that the d 18O values from the outer shell walls are more appropriate to be analysed for estimating their habitats in modern nautili. This scenario is supposed to be more significant in the shells that lived in water at greater depths, so that the discrepancy of d18 O values between contemporary secreted septa and outer shell wall might be useful as a criterion to recognize the deeper habitat depth in both modern and fossil cephalopods.

Naringenin (NRG) is a plant-derived flavonoid. Due to its antioxidant, anti-inflammatory, and analgesic activities it is beneficial to human health and is often used as a functional food ingredient; however, it has poor water solubility and low in vivo bioavailability. Therefore, the efficacy of NRG can be improved by enhancing its water solubility to increase gastrointestinal absorption. Conventional methods for the formulation of NRG are very complex and use toxic organic solvents, making them impractical for the production of functional foods. The objective of this study was to develop a safe and effective NRG-based functional food material. Previously, we established a technology to prepare amorphous solid dispersions (SDs) from functional food ingredients with poor water solubility and used hot-melt extrusion technology that is comparatively simple and does not involve the use of organic solvents. In this study, we prepared NRG SD and evaluated them both physicochemically and biochemically. NRG SD had superior water solubility and gastrointestinal absorption relative to native NRG and showed higher analgesic efficacy in rats than crystalline NRG. NRG SD was administered to mice in a mixed diet for 28 days, and organ weights and hematological/clinical biochemical parameters were assessed. NRG SD did not demonstrate severe adverse effects. The results suggest that NRG SD is a safe and highly efficacious formulation that can be used as a functional food material in the future.