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Hyperpigmentation that manifests through melasma and solar lentigo (age spots), although mostly harmless for health, bothers many people. Controlling the rate-limiting activity of tyrosinase is most effective for suppressing excessive melanin formation and accordingly recent research has focused on the maturation of tyrosinase. Salacia, a medicinal plant, has been used to treat diabetes in India and Sri Lanka. Salacia extract reportedly contains components that inhibit the activity of α-glucosidase. Salacinol, the active ingredient in Salacia extract, has unique thiosugar sulphonium sulphate inner salt structure. Here, we observed that the salacinol component of Salacia extract possesses anti-melanogenic activity in comparison to various existing whitening agents. Although the anti-melanogenic mechanism of salacinol is presumably medicated by inhibition of tyrosinase activity, which is often found in existing whitening agents, salacinol did not inhibit tyrosinase activity in vitro. Analysis of the intracellular state of tyrosinase showed a decrease in the mature tyrosinase form due to inhibition of N-linked oligosaccharide processing. Salacinol inhibited the processing glucosidase I/II, which are involved in the initial stage of N-linked glycosylation. Owing to high activity, low cytotoxicity and high hydrophilicity, salacinol is a promising candidate compound in whitening agents aimed for external application on skin.

The cause of hyperpigmentation, such as solar lentigo and seborrheic keratosis, is the excessive accumulation of melanin pigments in the epidermal basal layer. Melanin pigments are synthesized in the melanosomes, which are specific organelles produced by melanocytes in the basal layer. Melanosomes containing melanin pigments are transported to the neighboring keratinocytes. However, the behavior of melanosomes after being transported to the keratinocytes has been poorly understood. In this study, we focused on a lysosomal protease cathepsin V (CTSV) to clarify the mechanism underlying melanosome degradation in the keratinocytes. Using immunohistochemical observation, we found that CTSV was highly expressed across the entire epidermis in normal skin; however, CTSV expression levels were lower in the basal layer than those in the stratum corneum side in the hyperpigmented region. Moreover, we found that melanosome degradation was suppressed in CTSV knockdown cells. These results indicated that CTSV is involved in melanosome degradation.

We investigated the effect of consumption of a catechin-containing drink on body fat level and its safety in healthy adults. The beverage (250 ml/bottle) contained 215.3 mg of tea catechins mostly possessing a galloyl moiety, which included (-)-epigallocatechin gallate 74.6 mg, (-)-epicatechin gallate 34.1 mg, (-)-gallocatechin gallate 77.8 mg, (-)-catechin gallate 24.5 mg. We conducted a double-blind study with three parallel groups. Healthy subjects (98 men and 97 women) aged from 20 to 65 years old with 22.5 < body mass index (BMI) ≤ 30 kg/m2 were assigned to consume 3 bottles of placebo drink (control group), 2 bottles of catechin-containing drink and 1 bottle of placebo drink (low-dose group), or 3 bottles of catechin-containing drink (high-dose group), per day at mealtimes for 12 week (daily consumption of catechins was 41.1, 444.3 or 665.9 mg respectively). Compared to the value at 0 week, consumption of two or three bottles of catechin-containing drink results in significant decrease in body weight and BMI at 8 and 12 or 4, 8 and 12 week, respectively. Body weight and BMI was significantly decreased in both catechin groups compared with the control group from 4 to 12 week. The measurements of abdominal fat areas indicated significant reduction of total fat area and visceral fat area in both catechin groups compared with the control group at 12 week. Thus our present observations suggest that consumption of a catechin-containing drink may be useful for the prevention of obesity-related disorders.

Blood cholesterol-lowering effect and safety of tea catechins were examined in a placebo-controlled double-blind study in which a beverage containing tea catechins (a 250ml beverage containing 197.4mg of catechins) was given twice a day at breakfast and dinner for 12 weeks. The subjects used were adult males and females with mild and borderline hypercholesterolemia with the range of serum total cholesterol levels 180-259mg/dl (male/ female, 38/22; age, 48±9 years; total cholesterol, 222±20mg/dl), who were not taking drugs that may affect lipid metabolism. The study was initiated with a 2-week pre-observation period followed by a 12-week intake period and a 2-week post-observation period. The results revealed that the serum total cholesterol levels in the test beverage group (initial intake level) was significantly decreased at 8 weeks (228±23mg/dl to 220±21mg/dl, p

The relation between the rheological properties and the swallowing characteristics of vegetable juices fortified with 0–30.0% carrot puree (CP) was evaluated. The apparent viscosity of vegetable juices increased with increasing CP concentrations, and a increases in yield stress were observed at and above 17.5% CP. In a sensory evaluation, texture perceived in the oral cavity varied as between vegetable juices with >17.5% CP and those with

It was found that the method of sulfidation of cobalt oxide strongly affects the catalytic activities and selectivities of the resultant cobalt sulfide catalyst, as well as the calcination temperature of the cobalt oxide. When cobalt oxide was sulfided at 673 K by a temperature-programmed sulfiding method (a heating rate of 6 K min −1 ), catalytic activities for the hydrogenation of butadiene and the isomerization of 1-butene were considerably enhanced compared with those for cobalt sulfide prepared by isothermal sulfidation at 673 K. Results of temperature-programmed sulfiding (TPS), temperature-programmed reduction (TPR), and X-ray diffraction (XRD) suggest that the catalysts showing high catalytic activities after sulfidation are partially sulfided at 673 K and consist of the unsulfided cobalt core phases (COO or metallic Co). The sulfidation property of precursor cobalt oxides has been studied using TPS, simulating the sulfidation process of the cobalt sulfide catalysts. Two distinctly different kinds of sulfidation process are estimated by TPS measurements of the cobalt oxides. The calcination temperature of the precursor cobalt oxides strongly affects the sulfidation paths. They are differentiated in terms of the presence of a metallic Co intermediate. The relationship of the mechanism of sulfidation of the cobalt oxides to the generation of highly active sites is discussed.

Coronary artery spasm has an important function in the etiology of variant angina and other acute coronary syndromes. Abnormal activation of Rho-family GTPases has been observed in cardiovascular disorders, but the function of genetic variability in Rho-family GTPases remains to be evaluated in cardiovascular disorders. We examined the genetic variability of Rho-family GTPases and their regulators in coronary artery spasm. We performed a comprehensive candidate gene analysis of 67 single nucleotide polymorphisms with amino-acid substitution in Rho-family GTPases and their regulators in 103 unrelated Japanese patients with acetylcholine-induced coronary artery spasm and 102 control Japanese subjects without acetylcholine-induced coronary artery spasm. We noted an association of the single nucleotide polymorphism of ARHGAP9 (rs11544238, Ala370Ser) with coronary artery spasm (odds ratio =2.67). We found that ARHGAP9 inactivated Rac as RacGAP and that the mRNA level of ARHGAP9 was strongly detected in hematopoietic cells. ARHGAP9 negatively regulated cell migration. The Ala370Ser polymorphism counteracted ARHGAP9-reduced cell migration, spreading and adhesion. The Ala370Ser polymorphism in the ARHGAP9 gene is associated with coronary artery spasm. These data suggest that the polymorphism of ARHGAP9 has a critical function in the infiltration of hematopoietic cells into the endothelium and inflammation leading to endothelial dysfunction.

The effects of the starting cobalt salt were investigated on the cobalt—alumina interaction modes and cobalt dispersion in CoO/Al 2 O 3 , catalysts. The catalysts were characterized in oxidic, sulfided, and uncalcined states using temperature-programmed reduction, X-ray photoelectron spectroscopy, X-ray diffraction, and nitric oxide adsorption techniques. It was found that the cobalt—alumina interaction modes depend strongly on the starting salt. It was demonstrated that CoO/Al 2 O 3 catalysts prepared from cobalt acetate show higher cobalt dispersion and higher catalytic activity for thiophene hydrodesulfurization than the catalysts prepared from conventional cobalt nitrate. The proportion of Co 3+ species on CoO/Al 2 O 3 is significantly decreased when cobalt acetate is used instead of cobalt nitrate. On the basis of XPS characterization of uncalcined catalysts and a comparative study on CoO/Al 2 O 3 catalysts prepared from other cobalt precursors, it is proposed that with CoO/Al 2 O 3 , prepared from cobalt nitrate, the oxidation of Co 2+ to Co 3+ during calcination by coexisting NO − 3 anions on uncalcined precursors results in a high Co 3+ proportion and, consequently, poorly dispersed cobalt species.

The present study was aimed to evaluate the speech behaviors of normal young adults under DAF condition with an audiofilter.The feedback speech was distorted with a lowpass and a high-pass filter. The subjects were 21 young adults, 18 males and 13 females. Each subject read 100-word passages under DAF (delay time 200 msec) with all-pass filtering, low-pass filtering above 1, 200, 1, 700 and 2, 400Hz, and high-pass filtering below 1, 200, 1, 700 and 2, 400Hz. The feedback level was 65dB above each hearing threshold, and the sound was delivered to both ears. The speech behaviors were analysed with reference to reading time ratio and articulatory error, comparing with those under normal auditory feedback (NAF).The results were as follows:1. The speech behaviors were mostly disturbed under all-pass filtering.2. The speech behaviors under low-pass filtering were more disturbed than those under highpass filtering.3. There were little differences among speech behaviors under three conditions of filtering; 1, 200, 1, 700 and 2, 400Hz for low-pass and high-pass respectively.4. In general, the DAF effects on the male were greater than the female.5. It was concluded that the low frequency range of speech sound was mostly responsible for DAF effect.