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To protect the body against environmental threats, cosmetics can play important antiinflammatory and anti-aging roles. Many researchers have developed cosmetic ingredients using natural plant extracts or the active compounds of such extracts. In this study, we assessed the ability of extracts from the seeds of alfalfa (Medicago sativa L.) to affect skin cells. In a keratinocyte-derived cell line (HaCaT cells), alfalfa polysaccharide extract (APE) treatment triggered cornified envelope formation and increased the gene expression levels of filaggrin and involucrin, suggesting that APE increased epidermal cell differentiation. In addition, APE dramatically increased the mRNA and protein levels of claudin1, suggesting that it enhances tight junction formation. Finally, APE exerted antiinflammatory effects in keratinocytes by decreasing the LPSinduced production of proinflammatory cytokines. In primary normal human dermal fibroblasts (NHDF), APE increased procollagen synthesis and decreased elastase activity and metalloproteinase-1 (MMP) secretion. APE also showed superoxide dismutase (SOD)-like activity in a cell-free system, resulting in antioxidant effects. Finally, we found that the polysaccharides from alfalfa seeds used in our experiments consist mainly of galactose and mannose. Based on our findings, we conclude that APE may have potent skin-protective and skin-improving effects and could be developed as an important ingredient in cosmetics and medicines.

Simple Summary: The Najeoer Pond, which is the object of this study, was created to be utilized as a test bed for the restoration of endangered species and for carrying out ecological education on the pond ecosystem. To achieve these goals, the Najeoer Pond was created for diversity and stability purposes by first securing various water depths imitating natural lagoons and inducing the establishment of various vegetation types according to the depth. As a result of analyzing the vegetation settlement process for 12 years after its creation through vegetation cover, species composition, species diversity, and the ratio of exotic species, and comparing the results with those of natural lagoons, the Najeoer Pond has been shaped to resemble the diversity and stability of natural lagoons. The carbon absorption capacity of the littoral vegetation established around the pond was significantly higher than that of forest vegetation. In this respect, the Najeoer Pond was also deemed to have a high creation effect in terms of ecological function. Therefore, a stable pond with diversity can be created because vegetation diversity can be guaranteed as a result of securing the ecological diversity of various water depths. The Najeoer Pond was created in a rice paddy as a part of a plan to build the National Institute of Ecology. To induce the establishment of various plants, the maximum depth of the pond was 2.0 m, and diverse depths were created with a gentle slope on the pond bed. When introducing vegetation, littoral and emergent vegetation were first introduced to stabilize the space secured for the creation of the pond, whereas the introduction of other vegetation was allowed to develop naturally. In this pond, floating, emergent, wetland, and littoral plants have been established to various degrees, reflecting the water depth and water table. As a result of stand ordination, based on vegetation data obtained from the created Najeoer Pond and a natural lagoon selected as the reference site, the species' composition resembled that of the reference site. Diversity, based on vegetation type, community, and species, tended to be higher than that of the reference site. The proportion of exotic species increased due to the disturbance that occurred during the pond creation process but continued to decrease as the vegetation introduced during the creation of the pond became established. Considering these results comprehensively, the restorative treatment served to increase both the biological integrity and ecological stability of the pond and, thus, achieved the creation goal from the viewpoint of the pond structure. [ABSTRACT FROM AUTHOR]

All-trans retinoic acid (RA) is an effective anti-aging chemical substance widely used in skin-care products. RA compromises epidermal differentiation and induces keratinocyte proliferation, causing hyaluronic acid production through mechanisms that are not completely understood. Klotho protein causes the differentiation of human epidermal keratinocytes. Klotho gene expression is mediated by epidermal growth factor (EGF), which inhibits cell apoptosis in aging-related diseases. The klotho gene causes human aging syndrome, including short lifespan, skin atrophy, and osteoporosis. We investigated the relationship between RA and klotho in epidermal keratinocytes for the first time. In human epidermal keratinocytes, RA induced klotho gene expression. Treatment with both RA and recombinant klotho induced hyaluronic acid production in human epidermal keratinocytes. However, in klotho small interfering RNA (siRNA)-transfected keratinocytes, RA produced less hyaluronic acid than in the control group, indicating that RA may partially regulate hyaluronic acid production through a klotho-dependent pathway. Knockdown of klotho gene expression inactivated the EGFR-extracellular signal-regulated kinase (ERK) signaling pathway, which is involved in hyaluronic acid production. We concluded that the effect of RA on hyaluronic acid production is partly regulated through the klotho-mediated EGFR signaling pathway in human epidermal keratinocytes.

Green roofs provide various ecosystem services, including habitats for diverse organisms in urban areas where natural space is very scarce. This study aims to evaluate the restoration effects of green roofs created by applying an ecological restoration method to reinforce habitat function. The reference ecosystem selected for the ecological restoration of a roof was a Korean red pine stand established on Mt. Bulam, considering the soil depth, light, moisture conditions, etc., compared with the roof's environmental conditions. Ecological restoration was carried out by planting two-year-old pine seedlings and scattering surface soil collected from the pine stands. The pine trees showed geometrical growth in height and diameter and a high water-use efficiency. The ecological restoration of the green roofs demonstrated an ecological function for improving the urban climate through the mitigation of the urban heat island effect and high productivity, showing different functions depending on the greening method. The composition and diversity of vegetation and insects at the ecological restoration site were similar to those at the reference site, whereas the landscape architecture sites, which were created using the landscape architecture method, were different from the reference site. These results confirm that applying the ecological restoration method for rooftop greening resulted in better biological habitat function than applying existing landscape architecture methods. [ABSTRACT FROM AUTHOR]

The Korean Demilitarized Zone (DMZ) is an area where human disturbance has been strictly restrained for about seven decades since 1953. As a result, compared with rural and urban areas in Korea with similar ecological conditions, the landscape structure of the Korean DMZ today shows a big difference in that it has a riparian forest and lacks any of the artificial landscape elements, such as agricultural and residential areas. The vegetation maps made in the 1950s and those made in recent years of a model site that extends throughout the DMZ, the Civilian Control Zone (CCZ), and adjacent rural areas show that successional changes in the DMZ and CCZ areas are remarkable, while changes in the rural areas are not clear. Rice fields have been replaced by riparian forests, whereas young forests in areas previously subjected to excessive use and pine forests have been replaced by broad-leaved forests. Among the three landscape elements that changed, it was found that riparian zones, where natural disturbance is usually frequent, could mitigate the impacts of human disturbance and restore the original features of nature sooner than any other elements. The results of analyses on landscape change that focused on rice fields before the Korean War also showed similar results: most of these fields had turned into riparian vegetation. Stand ordination of riparian vegetation investigated in the CCZ, rural areas, and urban areas showed clear differences in species composition and diversity among regions. In this study, we confirmed the passive restoration of the Korean DMZ and CCZ through natural regeneration processes as a result of restricted human disturbance over a period of about seven decades. [ABSTRACT FROM AUTHOR]

All-trans retinoic acid (ATRA) influences cellular proliferation and differentiation but its mechanisms of action are not understood in keratinocytes. To investigate the potential mechanisms of action of ATRA in keratinocytes, microarray analysis of ATRA-treated normal human epidermal keratinocytes (NHEKs) was performed. Based on microarray data, we focused on insulin-like growth factor binding protein-6 (IGFBP-6), which is known to inhibit cellular senescence but has not been previously investigated in the context of ATRA-induced signaling in NHEKs. We verified that ATRA significantly increased IGFBP-6 gene and protein expression in NHEKs. Next, the effects of ATRA and IGFBP-6 on cell proliferation and senescence in H2O2-treated NHEKs were examined. IGFBP-6 was knocked-down using siRNA or overexpressed using pCMV-IGFBP-6. Cellular proliferation was observed using the bromodeoxyuridine (BrdU) incorporation assay. Cellular senescence was determined by monitoring SA-β-Gal staining and p21 expression. When IGFBP-6 was knocked down, cellular proliferation was inhibited, and the cellular senescence markers were increased. IGFBP-6 overexpression or ATRA treatment of H2O2-treated NHEKs rescued these effects. Taken together, our results suggest that ATRA prevents premature senescence-related skin damage at least in part by increasing IGFBP-6 expression, as shown herein in reactive oxygen species (ROS)-stimulated NHEKs.

Sorbus commixta is a tree of the Rosaceae family growing in Asia that has long been used to treat asthma and neuralgia. In a previous report, the chemical isolated from the bark of S. commixta was shown to suppress the production of nitric oxide (NO) and preinflammation by downregulating the NF-кB pathway in lipopolysaccharide (LPS)-induced RAW 264.7 cells. Vitiligo is an acquired immune disease, usually characterized by white spots on the skin; however, its exact cause has not been identified. This study assessed the effects of an ethanol extract of S. commixta twigs (STE) on melanocyte activation, as well as its antiinflammatory and antioxidant properties. STE significantly increased the proliferation and melanin content of B16 melanocytes. Because of the importance of tumor necrosis factor (TNF)-α in inflammatory diseases, including the stimulation of vitiligo, the antiinflammatory effects of STE were tested in TNF-α-stimulated dermal fibroblasts and keratinocytes. STE reduced the levels of expression of IL-6, IL-8 and TNF-α mRNA and proteins. To assess the underlying molecular mechanism, the effects of STE on the mitogen-activated protein kinase (MAPK) signaling process were analyzed in dermal fibroblasts. Results show that STE inactivated extracellular signal-regulated kinase (ERK). In addition, STE exhibited antioxidative properties in assays of DPPH radical scavenging activity. Taken together, these findings suggest that STE has potential therapeutic activity in vitiligo.

Decrease in processing speed due to increased resistance and capacitance delay is a major obstacle for the down-scaling of electronics.sup.1-3. Minimizing the dimensions of interconnects (metal wires that connect different electronic components on a chip) is crucial for the miniaturization of devices. Interconnects are isolated from each other by non-conducting (dielectric) layers. So far, research has mostly focused on decreasing the resistance of scaled interconnects because integration of dielectrics using low-temperature deposition processes compatible with complementary metal-oxide-semiconductors is technically challenging. Interconnect isolation materials must have low relative dielectric constants ([kappa] values), serve as diffusion barriers against the migration of metal into semiconductors, and be thermally, chemically and mechanically stable. Specifically, the International Roadmap for Devices and Systems recommends.sup.4 the development of dielectrics with [kappa] values of less than 2 by 2028. Existing low-[kappa] materials (such as silicon oxide derivatives, organic compounds and aerogels) have [kappa] values greater than 2 and poor thermo-mechanical properties.sup.5. Here we report three-nanometre-thick amorphous boron nitride films with ultralow [kappa] values of 1.78 and 1.16 (close to that of air, [kappa] = 1) at operation frequencies of 100 kilohertz and 1 megahertz, respectively. The films are mechanically and electrically robust, with a breakdown strength of 7.3 megavolts per centimetre, which exceeds requirements. Cross-sectional imaging reveals that amorphous boron nitride prevents the diffusion of cobalt atoms into silicon under very harsh conditions, in contrast to reference barriers. Our results demonstrate that amorphous boron nitride has excellent low-[kappa] dielectric characteristics for high-performance electronics. Thin films of amorphous boron nitride are mechanically and electrically robust, prevent diffusion of metal atoms into semiconductors and have ultralow dielectric constants that exceed current recommendations for high-performance electronics., Author(s): Seokmo Hong [sup.1] , Chang-Seok Lee [sup.2] , Min-Hyun Lee [sup.2] , Yeongdong Lee [sup.3] [sup.4] , Kyung Yeol Ma [sup.4] [sup.5] , Gwangwoo Kim [sup.1] , Seong In [...]

The difference in the leaf unfolding date of Mongolian oak obtained through MODIS image analysis between the urban center and the outskirts of Seoul was found to be seven days. The difference in the flowering date of cherry obtained through field observations was also found to be seven days between the urban center and the outskirts. The frequency of the abnormal shoot of Korean red pine differed by 71% between the urban center and the outskirts, and the length growth differed by 8.6 cm. There was a statistically significant correlation between the leaf unfolding date of Mongolian oak, the flowering date of the cherry, and the spatial difference in the frequency and length of the abnormal shoot of the Korean red pine. The temperature difference between the urban center and the outskirts of Seoul based on the mean temperature over the past 30 years was about 5 °C. The spatial difference in plant phenology showed a statistically significant negative relationship with the spatial difference in temperature. On the other hand, the spatial difference in temperature showed a statistically significant positive relationship with the spatial difference in the urbanization rate. These results are interpreted as the result of excessive land use during urbanization causing the heat island phenomenon, and the resulting temperature difference is reflected in the phenology of plants. These results are evidence that urbanization, which uses excessive land and energy, has a very significant impact on climate change. In addition, it is also evidence that sustainable land use could be an important means to achieve climate change adaptation and further solve climate change problems. [ABSTRACT FROM AUTHOR]

Seasonal changes can affect the physiological condition of the skin and cause various cutaneous disorders. The skin barrier function tends to worsen during winter when humidity is lower compared to other seasons. To determine the influence of relative humidity (RH) on the function of the skin barrier, we performed biological and histological assays using skin equivalents that were cultured under reduced humidity in an environmental humidity chamber. We found that reduced humidity led to decreased epidermal thickness and disruption of the skin barrier. Reduced humidity induced the decrease of filaggrin, loricrin and damage to tight junction. In addition, dipeptidyl peptidase-4 (DPP4), which has roles in the immunological process, was upregulated in a skin-equivalent model under reduced humidity. These results suggest that reduced humidity affects the skin barrier function and regulates the secretion of DPP4 in a skin-equivalent model.

Green tea from Camellia sinensis, a popular beverage worldwide, is also considered a herbal medicine. The bioactive compounds of green tea include polyphenols, polysaccharides, amino acids, and vitamins. Tea polyphenols are composed of various catechins such as epigallocatechin-3-gallate (EGCG), whereas polysaccharides include complex pectic substances and glycoproteins. Unfractionated C. sinensis leaf extracts show various pharmacological effects that are attributable to catechins, which include antimelanogenic properties. Most studies have focused on the biological function of catechins in green tea, and the effects of C. sinensis leaf extracts lacking catechins (CSLE-LC) have received little research attention. We examined the skin-whitening properties of the fraction lacking catechins. The melanin content in melan-a cells was significantly reduced, as has been shown for unfractionated C. sinensis extracts and catechins. We also elucidated the molecular mechanism underlying the antimelanogenic effects of CSLE-LC on skin melanocytes. Our results show that CSLE-LC acts through inhibition of MiTF and subsequent activation of extracellular-signal regulated kinase (ERK) to reduce tyrosinase protein levels. We confirmed the whitening ability of CSLE-LC using a human skin equivalent. Our findings provide the first evidence that CSLE-LC could exert efficient antimelanogenesis activity, and suggest that polysaccharides as well as catechins contribute to the whitening efficacy of C. sinensis leaf extracts.