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Background: Hyaluronan (HA) has a unique hydration capacity that contributes to firmness and bounciness of the skin. Epidermal HA declines with skin aging, which may lead to clinical signs of aging including skin wrinkles and loss of hydration and elasticity. Recently, we developed a new cosmetic agent 1‐ethyl‐β‐N‐acetylglucosaminide (β‐NAG2), which enhances HA production in cultured human keratinocytes. The aim of this study was to explore antiaging potential of β‐NAG2 in reconstructed human epidermal models and human clinical trial. Materials and methods: The amount of HA in β‐NAG2‐treated epidermal models by topical application was analyzed by enzyme‐linked immunosorbent assay (ELISA)‐like assay. A randomized, double‐blind and placebo‐controlled study was conducted in Japanese females (n = 33) by topically treating each side of the face with a lotion formulated with β‐NAG2 or placebo for 8 weeks. Results: Topically applied β‐NAG2 dose dependently increased HA production in epidermal models. Treatment with β‐NAG2‐formulated lotion significantly improved skin hydration and elasticity and reduced skin wrinkling in crow's foot areas when compared to the placebo formulation. Conclusion: Topically applied β‐NAG2 promoted epidermal HA production in vitro and showed antiwrinkle activity in vivo accompanying the improvement in skin hydration and elasticity. Our study provides a novel strategy for antiwrinkle care through β‐NAG2‐induced epidermal HA production. [ABSTRACT FROM AUTHOR]

Auditory and vestibular functions in vertebrates depend on the transduction of sound vibration or head acceleration into electrical responses in inner ear hair cells. Mechanoelectrical transduction occurs at the tip of stereocilia, which are polarized to form an orientational arrangement that determines directional sensitivity. It remains to be clarified when and how premature hair cells acquire their specialized structure and function in living animals. The developmental origin of inner ear hair cells has been studied in vivo in zebrafish embryos. Tether cells, a small number of ciliated cells associated with an "ear stone" (or otolith) in the embryonic zebrafish inner ear, are believed to be precocious hair cells. However, whether or not tether cells acquire hair bundles and mechanosensitivity remains unknown. In the present study, we investigated the morphological and functional development of tether cells. Immunohistochemical examination revealed that stereocilia appeared on the tether cell apex in a polarized arrangement at 22 h postfertilization (hpf). Labeling with FM1-43, a marker of functional mechanotransduction channels, and the in vivo electrophysiological recording of mechanotransducer responses in the developing inner ear demonstrated that tether cells acquired direction-selective mechanosensitivity at 23 hpf. These results revealed that tether cells begin to function as hair cells within an hour after the appearance of a polarized array of stereociliary bundles. Thus, the ciliary cells morphologically and functionally differentiate into the first sensory hair cells in the inner ear of the zebrafish. [ABSTRACT FROM AUTHOR]

Auditory perception in vertebrates depends on transduction of sound into neural signals in the inner ear hair cells (HCs) and on transmission of these signals to the brain through auditory (VIIIth) nerve afferents. To investigate the developmental acquisition of auditory inputs by the CNS, we have electrophysiologically and morphologically examined the process of acquisition of auditory responsiveness by zebrafish macular HCs and the Mauthner cells (M-cells) in vivo. The M-cells are a paired large reticulospinal neurons in the hindbrain; they receive direct inputs from the VIIIth nerve afferents and initiate an acoustic startle response. Whole-cell recordings from the M-cells showed that sound-evoked postsynaptic currents were first observed around 40 h postfertilization (hpf); during subsequent development, onset latency decreased and amplitude increased. The appearance and development of microphonic potentials in the inner ear coincided with those of the acoustic responses of the M-cell, whereas the functional auditory circuits from the macular HCs to the M-cell were already formed at 27 hpf. These results suggest that the functional maturation of inner ear after formation of the auditory pathway is a critical process in the acquisition of auditory inputs by CNS neurons. [ABSTRACT FROM AUTHOR]

A case of progressive systemic sclerosis associated with colonic involvement is described. Barium-enema examination revealed segmental involvement. Colonoscopic examination of the whole range of the involved colon revealed wide-mouthed diverticula with interspersed rigid areas and numerous ulcerations. These colonoscopic findings appeared to be distinct from those associated with tuberculosis and Crohn's disease. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the extent of inflammation and atrophy in the stomach of Helicobacter pylori-positive and -negative patients with chronic gastritis. Methods: Endoscopy with biopsies from the lesser curvatures of the antrum, angulus, middle body, and the greater curvature of the middle body of the stomach was performed in 59 patients with histologically confirmed chronic gastritis. The extent of atrophic gastritis was assessed endoscopically as well as histologically. H. pylori status was assessed by histology as well as enzyme-linked immunosorbent assay. The histological severity of chronic and acute inflammation, glandular atrophy, and intestinal metaplasia was assessed according to the Sydney system. Results: In H. pylori-positive patients, H. pylori was evenly distributed throughout the stomach when the extent of atrophic gastritis was limited to the antrum and the lesser curvature of the body, but disappeared from the antrum of patients with more extensive atrophic gastritis. The severity of acute and chronic inflammation at the greater curvature of the body increased with the extension of atrophic gastritis, in H. pylori-negative patients, the severity of chronic inflammation at the greater curvature of the body was significantly higher in patients with extensive atrophic gastritis than in those with a lesser extent of atrophic gastritis. Conclusion: At the greater curvature of the body, the development of atrophy is closely associated with the increase in the severity of inflammation, which is more marked in H. pylori-positive patients. [ABSTRACT FROM AUTHOR]