Synthesis and characterization of SSM@NiO/TiO2 p-n junction catalyst for bisphenol a degradation.

Photocatalyst immobilization on support materials is essential for large-scale applications. Here, we describe growth of a p-n junction catalyst (NiO/TiO2) on a stainless-steel mesh (SSM) support using a facile hydrothermal method. The morphological superiority of the composite over previously reported NiO/TiO2 catalysts was probed using scanning and transmission electron microscopy. Flower petal-like NiO grew uniformly on SSM, which was evenly covered by TiO2 nanoparticles. Theoretical and experimental X-ray diffraction patterns were compared to analyze the development of the composite during various stages of synthesis. The photocatalytic activity of a powdered catalyst and SSM@catalyst was compared by measuring bisphenol A (BPA) degradation. SSM@NiO/TiO2 achieved the highest rate of BPA degradation, removing 96% of the BPA in 120 min. Scavenging experiments were used to investigate the charge separation and degradation mechanism. SSM@NiO/TiO2 showed excellent reusability potential, achieving and sustaining 91% BPA removal after 10 rounds of cyclic degradation. Reusability performance, composite resilience, apparent quantum yields, and figures of merit suggest that SSM@NiO/TiO2 has excellent utility for practical applications.

Evaluation of facial skin age based on biophysical properties in vivo.

OBJECTIVE: The evaluation of skin age, reflecting overall facial characteristics, has not been established. Previous studies focused on visual assessment or individual-specific feature such as wrinkles or skin color. We studied the evaluation model of skin age index (SAI) including the overall aging features including wrinkles, skin color, pigmentation, elasticity, and hydration. METHODS: Total 300 healthy women aged between 20 and 69 years included in this study. Pearson correlation analysis performed to identify the key factors among the biophysical properties with aging and developed the prediction model of SAI. Statistical regression analysis and machine learning technique applied to build the prediction model using the coefficient of determination (R2 ) and root mean square error (RMSE). Validation study of the SAI model performed on 24 women for 6 weeks application with anti-aging product. RESULTS: Prediction model of SAI consisted of skin elasticity, wrinkles, skin color (brightness, Pigmented spot, and Uv spot), and hydration, which are major features for aging. The cforest model to assess a SAI using machine learning identified the highest R2 and lowest RMSE compared to other models, such as svmRadial, gaussprRadial, blackboost, rpart, and statistical regression formula. The cforest prediction model confirmed a significant decrease of predicted SAI after 6 weeks of application of anti-aging product. CONCLUSION: We developed a prediction model to evaluate a SAI using machine learning, and led to accurate predicted age for overall clinical aging. This model can a good standard index for evaluating facial skin aging and anti-aging products.

Efficacy of ethyl ascorbyl ether-containing cosmetic cream on blue light-induced skin changes.

BACKGROUND: Office workers are consistently exposed to blue light, mainly from sunlight and digital device. Recent studies report that blue light has various harmful effects, including cellular changes via reactive oxygen species. Studies on blue light-induced skin changes have only been conducted in vitro and have not been clinically confirmed. OBJECTIVE: We provide novel methods to evaluate the effect of the product on the recovery of skin changed by blue light. METHODS: Internet surveys were conducted for workers in their 20s and 40s regarding exposure time to blue light in various environments. To study the effects of long-term exposure to blue light (456 nm) on the skin, we designed three light intensity conditions, and various skin characteristics were observed. After blue light irradiation, various skin characteristics were analyzed before and after applying ethyl ascorbyl ether (EAE)-containing cosmetic cream for 2 weeks. RESULTS: When exposed to strong blue light for approximately 16 days, the L* value, skin hydration, transparency, and elasticity decreased, and the melanin index, erythema index, a* value, and b* value increased. Furthermore, after short-term blue light irradiation (dose, 269 J/cm2 , the equivalent of blue light exposure for approximately 38 days in daily life), the L* value and elasticity decreased, and the melanin index and erythema index increased. However, when EAE cream was applied on skin for 1-2 weeks, the skin recovered. CONCLUSION: This study clinically confirms the skin changes caused by blue light and the effect of EAE in relieving such changes.

Effect of Silica Nanoparticles Blocked with Epoxy Groups on the Crosslinking and Surface Properties of PEG Hydrogel Films.

Silica nanoparticles (G-SiNPs) blocked with 3-glycidoxypropyl trimethoxysilane (GPTS) were newly applied to hydrogel films for improving film coating properties and to distribute the epoxy groups on the film surface. The effects of the content of epoxy-functionalized G-SiNPs on the crosslinking features by photo-induced radical polymerization and the surface mechanical properties of the hydrogel films containing poly(ethylene glycol) dimethacrylate (PEGDMA) and glycidyl methacrylate (GMA) were investigated. The real-time elastic modulus of various PEG hydrogel mixtures with prepared particles was monitored using a rotational rheometer. The distribution of epoxy groups on the crosslinked film surface was directly and indirectly estimated by the elemental analysis of Si and Br. The surface mechanical properties of various hydrogel films were measured by nano-indentation and nano-scratch tests. The relationship between the rheological and surface properties of PEG-based hydrogel films suggests that the use of small amounts of G-SiNPs enhances the surface hardness and crosslinked network of the film and uniformly distributes sufficient epoxy groups on the film surface for further coating applications.

Effects of Pig Skin Collagen Supplementation on Broiler Breast Meat.

This study aimed to enhance the quality of broiler breast meat by adding pig skin collagen to feed. A total of 50 Ross 308 broilers were classified according to the following feeding regime for two weeks: basal diet (NC), basal diet+0.1% fish collagen (PC), basal diet+0.1% pig skin collagen (T1), basal diet+0.5% pig skin collagen (T2), and basal diet+1.0% pig skin collagen (T3). The moisture content was the highest in the PC group, and the protein content was the lowest in the T1 group (p<0.05). The fat content was higher in the T1 and PC groups, whereas the ash content was higher in the T3 group (p<0.05). Drip loss was the highest in the NC group and the lowest in the T2 group (p<0.05). Lightness was low in groups T2 and T3, redness was low in groups T2 and PC, and yellowness was low in groups T1, T2, and PC (p<0.05). The collagen content of the chicken breast was the highest in the T3 group, and that of the skin was the highest in the T1 group (p<0.05). The texture characteristics of springiness, cohesiveness, chewiness, and hardness were the highest in the T3 group (p<0.05). In conclusion, the supplementation of a broiler diet with pig skin collagen was found to increase the collagen content of the breast meat, indicating the improved quality of the broiler breast meat.

Age-related biophysical changes of the epidermal and dermal skin in Korean women.

INTRODUCTION: The clinical characteristics of skin were investigated to study the inter-relationship and changes in the biophysical properties of the epidermal and dermal layers associated with aging using noninvasive methods. METHODS: Our study included 100 healthy women aged between the early 20s and late 60s. Biophysical characteristics of skin such as color (brightness and spots), transparency, wrinkle on crow's feet, elasticity, hydration, sebum content, glossiness, and transepidermal water loss measured under controlled conditions. RESULTS: This study performed in a Korean population demonstrated that aging significantly affects human skin in terms of parameters such as wrinkles, skin color, elasticity, and epidermal hydration. Age-related changes in skin hydration showed varying patterns between the epidermis and dermis. Skin color showed heterogeneous characteristics between the upper and lower epidermal layers associated with aging. Skin elasticity and wrinkles were observed to show and inversely proportional relationship in the early 40s. CONCLUSIONS: We confirmed the significant influence of aging on the biophysical properties of skin and determined the distinct age-related biophysical changes in the epidermal and dermal layers of skin using noninvasive method. This study indicates the need for further research to investigate the distinctive age-related changes in characteristics of the epidermal and dermal layers of human skin.

Biophysical properties of striae rubra and striae alba in human skin: Comparison with normal skin.

BACKGROUND: Striae distensae are common dermal lesions that progress through two different stages: the striae rubra, which appears to be erythematous, and striae alba, which is characterized by a hypopigmented feature. The clinical characteristics between striae distensae stages and normal skin remain unknown. OBJECTIVES: We aimed to investigate the clinical characteristics according to stages of striae distensae in terms of their biophysical properties, using objective noninvasive measurements in comparison with adjacent normal skin. METHODS: Sixty-one healthy female subjects with striae distensae were included as follows: 30 with striae rubra and 31 with striae alba on the abdomen and thighs. Hydration of the epidermis and dermis, skin color brightness, and Erythema index were measured. Skin elasticity, roughness, and dermal echo-density of the skin with striae distensae and adjacent normal skin were also measured. RESULTS: Hydration of the epidermis and dermis showed no significant difference between the skin with striae distensae and normal skin. Brightness of skin with striae alba and normal skin was significantly higher than that of skin with striae rubra. Erythema index of skin with striae rubra was significantly higher than that of skin with striae alba and normal skin. Skin with striae rubra and striae alba had a rougher surface than normal skin. Elasticity and dermal echo-density were significantly lower in striae distensae skin. CONCLUSIONS: Striae rubra and striae alba had similar biophysical properties in terms of skin hydration, elasticity, roughness, and dermal density. Moreover, striae distensae have less elasticity, more roughness, and lower dermal density than normal skin.

Structural basis for the inhibition of human lysozyme by PliC from Brucella abortus.

Lysozymes are the first line of defense for a diverse range of organisms that catalyze the degradation of bacterial peptidoglycan. Gram-negative bacteria produce proteinaceous lysozyme inhibitors to protect themselves from the action of lysozymes. To date, MliC or PliC (membrane-bound or periplasmic inhibitor of c-type lysozyme, respectively) has been found in various Gram-negative bacteria. Here, we report the crystal structures of Brucella abortus PliC and its complex with human c-type lysozyme. The complex structure demonstrates that the invariant loop of MliC/PliC plays a crucial role in the inhibition of lysozyme via its insertion into the active site cleft of the lysozyme, as previously observed in the complex structure of Pseudomonas aeruginosa MliC and chicken c-type lysozyme. We identified a new binding interface between a loop adjacent to the active site of human lysozyme and a loop carrying Glu112 of B. abortus PliC, the structure of which was disordered in P. aeruginosa MliC. Because MliC/PliC family members have been implicated as putative colonization or virulence factors, the structures and mechanism of action of MliC/PliC will be relevant to the control of bacterial growth in animal hosts.

Structure of the periplasmic copper-binding protein CueP from Salmonella enterica serovar Typhimurium.

CueP was initially identified as a copper-resistance gene in Salmonella enterica serovar Typhimurium, which has evolved to survive in the phagosomes of macrophages. Recently, CueP was determined to be a periplasmic copper-binding protein and has been implicated in the transfer of copper ions to SodCII in the periplasm. In this study, the crystal structure of CueP has been determined, revealing a V-shaped dimeric structure. The conserved cysteine and histidine residues are clustered on the surface of one side of the C-terminal domain, suggesting that this cysteine- and histidine-rich region is related to the function of CueP. LC-MS/MS analysis established the presence of a disulfide bond between Cys96 and Cys176 under aerobic conditions. Subsequent biophysical analyses showed that the CueP protein binds copper and zinc, and the mutation of Cys104 to serine (C104S) dramatically reduced the binding affinity for copper and zinc, suggesting that the cysteine- and histidine-rich cluster is responsible for copper binding. This study provides a structural basis for the participation of CueP in the resistance of the intracellular pathogen Salmonella to copper.

Differential Localization of Pain-Related and Pain-Unrelated Neural Responses for Acupuncture at BL60 Using BOLD fMRI.

The objective of this study was to differentiate between pain-related and pain-unrelated neural responses of acupuncture at BL60 to investigate the specific effects of acupuncture. A total of 19 healthy volunteers were evaluated. fMRI was performed with sham or verum acupuncture stimulation at the left BL60 before and after local anesthesia. To investigate the relative BOLD signal effect for each session, a one-sample t-test was performed for individual contrast maps, and a paired t-test to investigate the differences between the pre- and post-anesthetic signal effects. Regarding verum acupuncture, areas that were more activated before local anesthesia included the superior, middle, and medial frontal gyri, inferior parietal lobule, superior temporal gyrus, thalamus, middle temporal gyrus, cingulate gyrus, culmen, and cerebellar tonsil. The postcentral gyrus was more deactivated before local anesthesia. After local anesthesia, the middle occipital gyrus, inferior temporal gyrus, postcentral gyrus, precuneus, superior parietal lobule, and declive were deactivated. Pre-anesthetic verum acupuncture at BL60 activated areas of vision and pain transmission. Post-anesthetic verum acupuncture deactivated brain areas of visual function, which is considered to be a pain-unrelated acupuncture response. It indicates that specific effects of acupoint BL60 are to control vision sense as used in the clinical setting.

Liver enzyme abnormalities during concurrent use of herbal and conventional medicines in Korea: a retrospective study.

Concurrent use of herbal medicine (HM) and conventional medicine (CM) is increasing. However, little is known about the prevalence of drug-induced liver injury (DILI) related to this concurrent use. In order to investigate changes in liver enzymes during concurrent use of HM and CM and to assess the prevalence of DILI related to their concurrent use, we screened for liver injury among inpatients at our institution who were administered both HM and CM for at least 14 days while hospitalized between 2006 and 2010. We used the Council for International Organization of Medical Science (CIOMS) laboratory criteria to define liver injury. Of the 892 patients included in the study, 34 (3.81%) had liver injury on admission and 21 (2.35%) had liver injury at discharge. Of the 48 cases that fulfilled the CIOMS laboratory criteria for liver injury, 34 had preexisting liver injury. The remaining 14 were analyzed, and five were concluded to have DILI, resulting in a prevalence of 5/892 (0.56%, with a 95% confidence interval of 0.07-1.05%). Overall, clinical symptoms of liver injury were mild. We thus contend that concurrent use of HM and CM is relatively safe.

Functional implications of an intermeshing cogwheel-like interaction between TolC and MacA in the action of macrolide-specific efflux pump MacAB-TolC.

Macrolide-specific efflux pump MacAB-TolC has been identified in diverse gram-negative bacteria including Escherichia coli. The inner membrane transporter MacB requires the outer membrane factor TolC and the periplasmic adaptor protein MacA to form a functional tripartite complex. In this study, we used a chimeric protein containing the tip region of the TolC α-barrel to investigate the role of the TolC α-barrel tip region with regard to its interaction with MacA. The chimeric protein formed a stable complex with MacA, and the complex formation was abolished by substitution at the functionally essential residues located at the MacA α-helical tip region. Electron microscopic study delineated that this complex was made by tip-to-tip interaction between the tip regions of the α-barrels of TolC and MacA, which correlated well with the TolC and MacA complex calculated by molecular dynamics. Taken together, our results demonstrate that the MacA hexamer interacts with TolC in a tip-to-tip manner, and implies the manner by which MacA induces opening of the TolC channel.

Immunohistochemical study on the expression of calcium binding proteins (calbindin-D28k, calretinin, and parvalbumin) in the cerebellum of the nNOS knock-out(-/-) mice.

Nitric Oxide (NO) actively participates in the regulation of neuronal intracellular Ca(2+) levels by modulating the activity of various channels and receptors. To test the possibility that modulation of Ca(2+) buffer protein expression level by NO participates in this regulatory effect, we examined expression of calbindin-D28k, calretinin, and parvalbumin in the cerebellum of neuronal NO synthase knock-out (nNOS((-/-))) mice using immunohistochemistry. We observed that in the cerebellar cortex of the nNOS((-/-)) mice, expression of calbindin-D28k and parvalbumin were significantly increased while expression of calretinin was significantly decreased. These results suggest another mechanism by which NO can participate in the regulation of Ca(2+) homeostasis.

Region-specific changes in the immunoreactivity of vasoactive intestinal peptide and pituitary adenylate cyclase-activating polypeptide receptors (VPAC2, and PAC1 receptor) in the aged rat brains.

Pituitary adenylate cyclase-activating peptide (PACAP) and vasoactive intestinal peptide (VIP) have been implicated in a large array of physiological and patho-physiological processes through their receptors (VPAC(1), VPAC(2), and PAC(1) receptor) in the central nervous system. Previously, we demonstrated age-related decreases in VPAC(1) receptor expression in the rat brain providing a possible basis of several age-induced functional changes in the aged brain. In the current study, we also examined age-related changes in PAC(1) and VPAC(2) receptors in aged rat brains using an immunohistochemical approach. We found that PAC1 immunoreactivity was significantly increased in the hippocampal formation, hypothalamus, thalamus, midbrain septal nuclei, and white matter of aged rats compared with young control rats although its distribution pattern was not altered. In contrast, both distribution pattern and immunoreactivity of VPAC(2) receptor remained unchanged in aged rat brains. These results suggest that the PACAP/VIP receptors exhibit specific expressional changes in the aged brain and that these specific changes could underlie age-associated memory and cognitive functional declines as well as several other age-induced functional changes in the brain. However, the exact regulatory mechanism and its functional significance require further elucidation.

Oncogenic Ras-mediated downregulation of Clast1/LR8 is involved in Ras-mediated neoplastic transformation and tumorigenesis in NIH3T3 cells.

Oncogenic Ras proteins transform cells by way of multiple downstream signaling pathways that promote the genesis of human cancers. However, the exact cellular mechanisms by which downstream targets are regulated are not fully understood. Here, we show that oncogenic Ras reduced Clast1/LR8 transcript levels in mouse NIH3T3 fibroblasts and human WI38 fibroblasts. Clast1/LR8 transcript was undetectable in H460, A549, and H1299 cells showing high Ras activity, but was relatively abundant in DMS53 cells displaying low Ras activity. We also showed that K-Ras siRNA restored Clast1/LR8 expression in H460 and A549 cells, and that inhibitors of DNA methylation and histone deacetylation reversed oncogenic H-Ras-mediated suppression of Clast1/LR8 transcription. Additionally, ectopic expression of Clast1/LR8 inhibited serum-stimulated phosphorylation of ERK1/2 and Akt in H-RasV12-transformed NIH3T3 cells. We further showed that the expression of Clast1/LR8 interfered with oncogenic Ras-induced NIH3T3 cell transformation and invasion. Finally, our results showed that Clast1/LR8 inhibited Ras-induced proliferation of, and tumor formation by, oncogenic H-RasV12-transformed NIH3T3 cells in vivo. This study identifies the downregulation of Clast1/LR8 as a potentially important mechanism by which oncogenic Ras-mediated neoplastic transformation occurs.

Crystal structure and functional insight of HP0420-homolog from Helicobacter felis.

Helicobacter pylori infect more than half of the world's population and are considered a cause of peptic ulcer disease and gastric cancer. Recently, hypothetical gene HP0421 was identified in H. pylori as a cholesterol alpha-glucosyltransferase, which is required to synthesize cholesteryl glucosides, essential cell wall components of the bacteria. In the same gene-cluster, HP0420 was co-identified, whose function remains unknown. Here we report the crystal structure of HP0420-homolog of H. felis (HF0420) to gain insight into the function of HP0420. The crystal structure, combined with size-exclusion chromatography, reveals that HF0420 adopts a homodimeric hot-dog fold. The crystal structure suggests that HF0420 has enzymatic activity that involves a conserved histidine residue at the end of the central alpha-helix. Subsequent biochemical studies provide clues to the function of HP0420 and HF0420.

Periplasmic domain of CusA in an Escherichia coli Cu+/Ag+ transporter has metal binding sites.

The resistance nodulation division (RND)-type efflux systems are utilized in Gram-negative bacteria to export a variety of substrates. The CusCFBA system is the Cu(+) and Ag(+) efflux system in Escherichia coli, conferring resistance to lethal concentrations of Cu(+) and Ag(+). The periplasmic component, CusB, which is essential for the assembly of the protein complex, has Cu(+) or Ag(+) binding sites. The twelve-span membrane protein CusA is a homotrimeric transporter, and has a relatively large periplasmic domain. Here, we constructed the periplasmic domain of CusA by joining two DNA segments and then successfully expressed and purified the protein. Isothermal titration calorimetry experiments revealed Ag(+) binding sites with Kds of 10(-6)-10(-5) M. Our findings suggest that the metal binding in the periplasmic domain of CusA might play an important role in the function of the efflux pump.