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In the pyroprocessing of used nuclear fuel, it is difficult to recover U in a recyclable form from LiCl–KCl eutectic salt containing a high concentration of rare earths (REs) by co-deposition of U and RE. To derive a solution to this problem, it is necessary to develop a technology to reduce the RE concentration or separate the RE in the salt. To this end, an integrated process of chemical conversion of UCl3 into an oxide form and electro-deposition of NdCl3 in a metal form was evaluated using a simulated LiCl–KCl salt containing about 1.4 wt% of UCl3 and 4.0 wt% NdCl3 in this study. Through the integrated process, higher than 99% conversion efficiency of U was obtained and the concentration of Nd in the simulated salt was reduced to less than 1/100. It is expected that the integrated process also can be applied effectively to the recovery of U from LiCl–KCl eutectic salt containing a high concentration of RE. [ABSTRACT FROM AUTHOR]

CaCO3 powder containing C-14, which has a long half-life, is generated from the treatment process of spent activated carbons from the air cleaning system in a nuclear facility, can be decomposed into CaO and CO2 gas at a temperature above 600 °C. This CaCO3 must be fabricated into a stable waste form for final disposal at a temperature below 600 °C. In this study, tests on the solidification of CaCO3 into a waste form were conducted using a bismuth oxide glass with a low melting point. The CaCO3 was solidified into a homogeneous glass–ceramic waste form with a waste loading of 40 wt% at 460 °C without CaCO3 decomposition. This waste form had high values of density (3.15 g/cm3) and compressive strength (42.09 MPa), and it was confirmed through leaching tests (ANS 16.1, PCT) that the waste form also had a high chemical durability. [ABSTRACT FROM AUTHOR]

Activated carbon wastes from the air cleaning system in a nuclear facility contain a long half-life value of 14C (5700 years). This 14C is converted into a gaseous form of 14CO2 during a treatment process of the activated carbon wastes, and it is vented with a considerable amount of CO2 gas. This CO2 gas must be immobilized in a stable waste form with a minimized volume for final disposal. For this reason, carbonation tests of CO2 were conducted in accelerated CO2 carbonation equipment using Ca(OH)2, and fabrication tests of the CO2 carbonation products into a waste form were performed using a low melting glass in this study. Through the carbonation tests, an optimal condition was determined to achieve a high CaCO3 production rate (214 kg/m3 h). In the fabrication tests, it was confirmed that the carbonation product can be fabricated into a homogenous glass-ceramic waste form with a high density (3.1 g/cm3) at 450 °C by using a low melting glass with the Bi2O3–B2O3–ZnO–SiO2 system. [ABSTRACT FROM AUTHOR]

The SP-HyBRID process, which has a similar performance to commercial technologies for the decontamination of a nuclear reactor coolant system, can reduce the secondary waste generation significantly. However, the process has a problem of discharging decontamination wastewater every cycle. In this study, an improved SP-HyBRID process that can conduct the process cycles continuously without discharging decontamination wastewater every cycle was designed. It was confirmed that the improved process could be effectively applied to equipment for a decontaminating test of contaminated components, and the waste reduction can be close to 15% when compared with the existing SP-HyBRID process. [ABSTRACT FROM AUTHOR]

Estimation of centerline temperature of nuclear glass waste form for each waste stream is very essential in the period of storage because the centerline temperature being over its glass transition temperature results in the increase of leaching rate of radioactive nuclides due to the devitrification of glass waste form. Here, to verify the effects of waste form diameter and transuranic element content in the rare earth waste on the centerline temperature of the waste form, the surrogate rare earth glass waste generated from pyrochemical process was immobilized with SiO 2 Al 2 O 3 B 2 O 3 glass frit system, and thermal properties of the rare earth glass waste form were determined by thermomechanical analysis and thermal conductivity analysis. The estimation of centerline temperature was carried out using the experimental thermal data and steady-state conduction equation in a long and solid cylinder type waste form. It was revealed that thermal stability of waste form in case of 0.3 m diameter was not affected by the TRU content even in the case of 80% TRU recovery ratio in the electrowinning process, meaning that the waste form of 0.3 m diameter is thermally stable due to the low centerline temperature relative to its glass transition temperature of the rare earth glass waste form. [ABSTRACT FROM AUTHOR]

The pyrochemical process for the recycling of used nuclear fuels generates LiCl and LiCl–KCl waste salt during a series of processes. In particular, for the reduction of LiCl–KCl waste volume, radioactive rare earth nuclides in the LiCl–KCl waste salt are separated by a phosphorylation precipitation reaction, generating rare earth phosphate waste in a powder form. In this study, for the immobilization of rare earth phosphate wastes, rare earth calcium phosphate (RCP) glass waste forms have been fabricated using a CaO–P 2 O 5 glass system under a moderate vitrification temperature of below 1200 °C. Vitrification properties of NdPO 4 , which is a representative rare earth phosphate material have been investigated through XRD, SEM, EDX, DSC, IR, and density measurements. The RCP glass waste form fabricated from the 4CaO–6P 2 O 5 system showed an immobilization capacity of about 32 wt.% NdPO 4 waste loading. Also, chemical durabilities of RCP glass waste forms are investigated by PCT-A test. [ABSTRACT FROM AUTHOR]

Abstract: Salt separation and recovery from the salt wastes generated from a pyrochemical process is necessary to minimize the high-level waste volumes and to stabilize a final waste form. In this study, the thermal behavior of the LiCl–KCl eutectic salts containing rare earth oxychlorides or oxides was investigated during a vacuum distillation and condensation process. LiCl was more easily vaporized than the other salts (KCl and LiCl–KCl eutectic salt). Vaporization characteristics of LiCl–KCl eutectic salts were similar to that of KCl. The temperature to obtain the vaporization flux (0.1gmin−1 cm−2) was decreased by much as 150°C by a reduction of the ambient pressure from 5Torr to 0.5Torr. Condensation behavior of the salt vapors was different with the ambient pressure. Almost all of the salt vapors were condensed and were formed into salt lumps during a salt distillation at the ambient pressure of 0.5Torr and they were collected in the condensed salt storage. However, fine salt particles were formed when the salt distillation was performed at 10Torr and it is difficult for them to be recovered. Therefore, it is thought that a salt vacuum distillation and condensation should be performed to recover almost all of the vaporized salts at a pressure below 0.5Torr. [Copyright &y& Elsevier]

Abstract: In this study, a vacuum distillation of a mixture of LiCl–KCl eutectic salt and rare-earth oxidative precipitates was performed to separate a pure LiCl–KCl eutectic salt from the mixture. Also, a dechlorination and oxidation of the rare-earth oxychlorides was carried out to stabilize a final waste form. The mixture was distilled under a range of 710–759.5Torr of a reduced pressure at a fixed heating rate of 4°C/min and the LiCl–KCl eutectic salt was completely separated from the mixture. The required time for the salt distillation and the starting temperature for the salt vaporization were lowered with a reduction in the pressure. Dechlorination and oxidation of the rare-earth oxychlorides was completed at a temperature below 1300°C and this was dependent on the partial pressure of O2. The rare-earth oxychlorides (NdOCl/PrOCl) were transformed to oxides (Nd2O3/PrO2) during the dechlorination and oxidation process. These results will be utilized to design a concept for a process for recycling the waste salt from an electrorefining process. [Copyright &y& Elsevier]

Allergic contact dermatitis, which is mediated by activated T cells through a Type IV reaction, is usually believed to persist throughout life. There have been several reports of spontaneous loss of sensitization, e.g., loss of previous patch test reaction or loss of allergic contact dermatitis withal continuous exposure to the allergens. However, these have not been well quantified. The aim of this study was to confirm the development of desensitization or hyposensitization with the aid of objective measurements. A total of 18 patients with alopecia areata, who had received 4 months diphenylcyclopropenone (DPCP) contact immunotherapy, were patch tested and the responses were measured by laser Doppler blood flowmetry (LDF) and transepidermal water loss (TEWL). Patch tests were performed 2X, before and after 4 months of immunotherapy. To determine whether local desensitization developed, we compared change of DPCP concentrations producing mild contact dermatitis on the scalp. Our results showed that systemic and local hyposensitization occurred in human subjects by weekly applications of low concentrations of DPCP for 4 months. LDF seems to be more correlated with visual scores than TEWL measurement. [ABSTRACT FROM AUTHOR]

The aim of nuclear facility decommissioning is to make local settlements safe, sustainable and professedly acceptable. The challenges are the clean-up of the nuclear site and waste management. This means a definite promise in terms of safety and security, taking into account social and environmental accountability. There is an essential need to develop safe and efficient methods for nuclear decommissioning. Thus, chemical decontamination technology is of great significance to the decommissioning of nuclear energy facilities. In particular, chemical decontamination technology is applicable to the pipelines and internal loop. The iron-rich oxides, such as Fe3O4 or NiOFe2O3, of a nuclear power plant should have sound decontamination follow-through and should put through a very small amount of secondary waste. It is important to be able to detect and quantify hydrazine in decontamination situations with high sensitivity and selectivity. A colorimetric assay is a technique used to determine the concentration of colored compounds in a solution. However, detecting targeted species rapidly and easily, and with high sensitivity and specificity, is still challenging. Here, the catalytic reaction of oxidants in the p-dimethylaminobenzaldehyde and hydrazine reaction is elucidated. Oxidants can catalyze the reaction of hydrazine and p-dimethylaminobenzaldehyde to form an azine complex such as p-dimethylaminobenzaldazine, with high selectivity and sensitivity within 30 min at ambient temperatures. In the absence of an oxidant such as iron or hydrogen peroxide no detectable colorimetric change was observed by the reaction of p-dimethylaminobenzaldehyde and hydrazine unless an external oxidant was present in the system. In this study, we demonstrated a colorimetric method for the sensitive detection of hydrazine decomposition in the chemical decontamination process. Furthermore, the colorimetric response was easy to monitor with the unaided eye, without any sophisticated instrumentation. This method is thus suitable for on-site detection of contamination in a nuclear facility. In addition, this colorimetric method is convenient, non-invasive, free of complex equipment, and low-cost, making it possible to analyze hydrazine in industrial nuclear facilities. The proposed method was successfully applied to the determination of hydrazine decomposition in the nuclear decontamination process. [ABSTRACT FROM AUTHOR]

Gold sodium thiosulfate (GSTS) is reputed to be the most reliable gold antigen, but control studies are still required. Although Koreans have more varied sources of contact with gold, such as herbal medicines with gold coatings and indwelling gold acupuncture needles, no epidemiological studies have been performed. This study examined the frequency and sources of contact allergy to gold in South Korea by a multicenter study. Patch testing with 0.5% GSTS in pet. was conducted in 255 eczema patients and 58 control subjects. Results were observed at 21 days (D) to ensure there were no undetected late reactions in 54 observed patients and 47 controls. 8 (3.1%) of the 255 patients reacted positively to GSTS, including 1 with a late reaction. 1 of the 58 controls showed a positive reaction to GSTS on D4 with a negative reaction on D14. Clinical relevance was lacking in the patients with positive reactions. Unexpectedly, the above particular sources of gold contact gave rise to few allergic reactions in our patients. [ABSTRACT FROM AUTHOR]

A test was conducted to separate Cd from Cd/LiCl-KCl salt using a stainless steel basket with holes 0.5 mm in size. A thermal cycle test of Cd in the mesh basket was repeated 15 times to confirm the containment property. U was recovered from a bare Cd-U alloy via distillation at a low temperature of around 400-500 °C in a morphology of porous particles, showing no evidence for the bumping of the Cd-U alloy. The U recovery efficiency at a kg-scale reached 100%. [ABSTRACT FROM AUTHOR]

The article features the Korean Dermatological Association (KDA) and the Korean Society for Investigative Medicine (KSID). It states that the KDA was built by dermato-urologists after the Second World War, and presently, it consists of 1,641 active members with a 1-year term president, and a chairman of the board of directors with a 2-year term. Moreover, the KSID was established during the first general meeting and scientific congress of 150 members in March 1991.

U recovery test was performed on a Zn-U alloy to confirm the feasibility of Zn as an alternative cathode material. An evaporation test of pure Zn first confirmed that Zn started to evaporate at above 450 °C. Next, a U recovery test was performed using liquid Zn in which U was electrochemically deposited. U was successfully recovered via distillation at 800 °C, leaving a disk-shaped product. The product was mostly U, indicating that the Zn was completely removed. These results confirm the feasibility of Zn as a cathode material, which offers the advantage of a lower operation temperature compared to Cd distillation. [ABSTRACT FROM AUTHOR]

This article discusses the case of a 46 year old patient with itchy skin lesions. A 46-year-old male patient suffering with itchy skin lesions of 3 to 4 years' duration on both hands and forearms. During his work, he has occasionally washed his hands and forearms with undiluted halasol, containing 4-6% sodium hypochicrite, and betadine as antiseptics. He has also been in contact with various antibiotics. After avoidance of halasol, his skin eruption improved markedly, especially on the forearms. However, hyperkeratotic and mildly cezematous skin lesions remained one month later, probably due to his wet work.

The pyrochemical process, which uses a dry method to recycle used nuclear fuel generates waste LiCl-KCl salt containing radioactive lanthanide elements. To reuse LiCl-KCl salt, the lanthanide elements are separated through a precipitation method promoted by oxygen sparging and the separated fission product of lanthanide oxide should be fabricated into durable wasteforms sustainable for several 1,000 years to store in a final geological repository. Herein, we report the fabrication of a borosilicate glass based wasteform with a glass matrix of SiO-AlO-BO having a high waste loading of 50 wt% lanthanide oxide. Th physical properties of four kinds of wasteforms having a different lanthanide oxide waste composition were evaluated. To investigate the long-term physical stability of each sample having 50 wt% lanthanide oxide waste loading, time-temperature-transformation (TTT) test was conducted at 500 and 700 °C for 60 and 180 h, and the physical properties were evaluated after each TTT test. [ABSTRACT FROM AUTHOR]

The separation characteristics of surrogate rare-earth fission products in a eutectic (LiCl–KCl) molten salt were investigated. This system is based on the eutectic salt used for the pyroprocessing treatment of used nuclear fuel (UNF). The investigation was performed using an integrated rare-earth separation apparatus comprising a precipitation reactor, a solid detachment device, and a layer separation device. To separate rare-earth fission products, a phosphate precipitation method using both Li3PO4 and K3PO4 as a precipitant was performed. The use of an equivalent phosphate precipitant composed of 0.408 molar ratio-K3PO4 and 0.592 molar ratio-Li3PO4 can preserve the original eutectic ratio, LiCl-0.592 molar ratio (or 45.2wt%), as well as provide a high separation efficiency of over 99.5% under conditions of 550°C and Ar sparging when using La, Nd, Ce, and Pr chlorides. The mixture of La, Nd, Ce, and Pr phosphate had a typical monoclinic (or monazite) structure, which has been proposed as a reliable host matrix for the permanent disposal of a high-level waste form. To maximize the reusability of purified eutectic waste salt after rare-earth separation, the successive rare-earth separation process, which uses both phosphate precipitation and an oxygen sparging method, were introduced and tested with eight rare-earth (Y, La, Ce, Pr, Nd, Sm, Eu and Gd) chlorides. In the successive rare-earth separation process, the phosphate reaction was terminated within 1h at 550°C, and a 4–8h oxygen sparging time were required to obtain over a 99% separation efficiency at 700–750°C. The mixture of rare-earth precipitates separated by the successive rare-earth separation process was found to be phosphate, oxychloride, and oxide. Through the successive rare-earth separation process, the eutectic ratio of purified salt maintained its original value, and impurity content including the residual precipitant of purified salt can be minimized. [ABSTRACT FROM AUTHOR]

Abstract: Background: Chemicals with a molecular weight <500 and adequate lipid solubility can penetrate the intact human skin. As many lipid ingredients in moisturizers have molecular weights <500, the lipid ingredients may penetrate into the skin and affect skin responses to UV; however, little is known about this phenomenon. Objective: To evaluate the effects of major lipid ingredients in moisturizers on skin responses to UV in tape-stripped human skin in vivo. Methods: We evaluated the effects of three major lipid ingredients in moisturizers (cholesterol, linoleic acid, and a synthetic ceramide, N-oleoyl-phytosphingosine) on skin responses to UV in the tape-stripped skin of healthy volunteers. After 2 days of lipid-application, the areas were irradiated with UV, and skin samples were obtained 24h after irradiation. Histologic features and the expression of the markers of collagen metabolism and inflammatory mediators were evaluated. Results: Compared to vehicle, topical cholesterol significantly decreased the degree of dermal inflammatory infiltrates and exocytosis, and also decreased the expression of MMP-1, IL-6, and IL-1ß mRNA. In contrast, topical linoleic acid increased the induction of apoptotic cells, and the expression of MMP-1 and IL-6 mRNA. N-oleoyl-phytosphingosine increased the expression of MMP-1 and IL-6 mRNA, while decreasing the expression of COX-2 mRNA. Conclusions: Topical cholesterol can protect the barrier-disrupted skin against UV-induced damage, while linoleic acid or N-oleoyl-phytosphingosine alone has the potential to aggravate the damage. [Copyright &y& Elsevier]

Molten salt oxidation (MSO) is one of the promising alternative destruction technologies for chlorinated organics, because it is capable of trapping chlorine during organic destruction. This study investigated the characteristics of a two-stage MSO reactor system for the destruction of CCl4 and C6H5Cl. Investigated parameters were the MSO reactor temperature (from 1023K to 1223K) and the excess oxidizing air feed rate (50% and 100%). The destruction of chlorinated solvents is substantial in the Li2CO3–Na2CO3 eutectic molten salt, irrespective of the tested condition. However, further oxidation of CO, which is found to be the major destruction product, is not substantial due to the limited temperature and gas residence time in the MSO reactor. Increases in the reactor temperature as well as those in the oxidizing air feed rate consistently lead to decreased emissions of carbon monoxide. No significant influence of the MSO reactor operating condition on the chlorine capturing efficiency was found. Over 99.95% and 99.997% of the chlorine was captured in the hot MSO reactors during the C6H5Cl and CCl4 destructions, respectively. This result suggests a relatively low potential of the MSO system in the recombination of chlorinated organics, when compared to a conventional incineration system. [Copyright &y& Elsevier]

Abstract: Eicosapentaenoic acid (EPA) is an omega-3 (ω-3) polyunsaturated fatty acid (PUFA), which has anti-inflammatory and anti-cancer properties. Some reports have demonstrated that EPA inhibits NF-κB activation induced by tumor necrosis factor (TNF)-α or lipopolysaccharide (LPS) in various cells. However, its detailed mode of action is unclear. In this report, we investigated whether EPA inhibits the expression of TNF-α-induced matrix metalloproteinases (MMP)-9 in human immortalized keratinocytes (HaCaT). TNF-α induced MMP-9 expression by NF-κB-dependent pathway. Pretreatment of EPA inhibited TNF-α-induced MMP-9 expression and p65 phosphorylation. However, EPA could not affect IκB-α phosphorylation, nuclear translocation of p65, and DNA binding activity of NF-κB. EPA inhibited TNF-α-induced p65 phosphorylation through p38 and Akt inhibition and this inhibition was IKKα-dependent event. Taken together, we demonstrate that EPA inhibits TNF-α-induced MMP-9 expression through inhibition of p38 and Akt activation. [Copyright &y& Elsevier]

The characteristics of molten salt oxidation (MSO) reactors for the destruction of chlorobenzene (C6H5Cl) and trichloroethylene (C2HCl3) were investigated. The influences of temperature, oxidizing air rate and gas residence time on the organic destruction reactions were investigated by both experimental and modeling studies. Various oxidation by-products such as C6H6, C6H5Cl, CCl4, C2H5CH3, CH2, C2H2, C2H4, CO and HCl were produced in the primary MSO reactor but these were substantially destroyed or collected in the secondary MSO reactor. The results of model predictions by using the CHEMKIN III program were generally in agreement with the experimental investigations. Both results suggested that an increase in the stoichiometric air rate from 50% to 150% does not increase the reaction rates significantly. However, it was found that a little increase in the temperature can considerably reduce the emission of carbon monoxide, which was found to be the only incomplete reaction product. [Copyright &y& Elsevier]

To determine whether the potency of botulinum toxin A (BTA) decreases after being reconstituted with normal saline and stored in refrigerator, we injected one side of the extensor digitorum brevis muscle with 2.5 units of botulinum toxin A that had been immediately reconstituted with saline, and the contralateral side with identical material that had been reconstituted and stored in a refrigerator for preselected periods (1, 2, and 4 weeks) in 32 healthy volunteers. Mean compound muscle action potential amplitudes expressed as a percentage of the baseline amplitude were more reduced in sides injected with immediately reconstituted BTA than in sides injected with BTA stored for 1 week or more ( P < 0.05). No bacterial growth was observed in any stored BTA samples. Storage of reconstituted BTA at low temperatures may affect the potency of the toxin. Therefore, the use of BTA after refrigerated storage is not recommended. © 2006 Movement Disorder Society [ABSTRACT FROM AUTHOR]

Abstract: The effects of the gas velocity (0.05–0.22m/s) and temperature (870–970°C) on the gas holdup and the gas phase axial dispersion coefficient have been studied in a molten salt oxidation reactor (0.076m i.d.×0.653m H., air-molten sodium carbonate salt two-phase system). The gas phase holdup and the amount of the axial gas phase dispersion coefficient were experimentally evaluated by means of the pressure drop measurement and residence time distribution (RTD) experiments using inert tracer gas (CO), respectively. Results indicated that the gas holdup increases with an increasing temperature, but the increasing rate of the gas holdup decreases with an increasing gas velocity. The gas phase axial dispersion coefficients show an asymptotic value with an increasing gas velocity due to the plug-flow like behavior at a higher gas velocity. Temperature has positive effects on the gas phase axial dispersion. To detect the regime characteristics, a spectral method based on the differential pressure fluctuation has been applied, which enables us to obtain the flow characteristics in the MSO reactor. [Copyright &y& Elsevier]

Abstract: Long term and repeated exposure of ultraviolet (UV) light, a harmful environmental stress, on the skin often induces chronic skin diseases such as skin cancer as well as photoaging (premature skin aging), and the mechanisms of these skin damages are closely associated with up-regulation of matrix metalloproteinases (MMPs) activities. Here we investigated the effect of tiarellic acid on the expressions of MMP-1 and type 1 procollagen in ultraviolet irradiation of cultured human skin fibroblasts. Tiarellic acid reduced the expression of MMP-1 and induced the expression of type 1- procollagen at the protein levels in a dose-dependent manner by ultraviolet irradiation. Taken together, our results suggest that tiarellic acid plays an important role in the reduction of MMP-1 and induction of type 1- procollagen by ultraviolet irradiation. [Copyright &y& Elsevier]

Molten salt oxidation is one of the promising alternatives to incineration for chlorinated organics without the emission of chlorinated organic pollutants. This study investigated the behavior of three hazardous metals (Cd, Pb, and Cr) and four radioactive metal surrogates (Cs, Ce, Gd, and Sm) in the molten Na2CO3 oxidation reactor during the destruction of PVC plastics. In the tested temperature ranges (1143–1223 K) and NaCl content (0–10%), the impact of temperature on the retention of cadmium and lead in the molten salt reactor was very small, but that of the NaCl content for their retention was relatively higher. The influence of NaCl accumulation was, however, proven to be practically negligible due to the low-temperature operating characteristics of the molten salt oxidation system. Neither temperature increase nor chlorine accumulation in the MSO reactor reduced the retention of Cr, Ce, Gd, and Sm. Over 99.98% of these metals remained in the reactor. The influence of the temperature on the cesium behavior is relatively large for a chlorine addition, however, over 99.7% of cesium remained in the reactor throughout the entire test. The experimental metal entrainment rate and the entrained metal particle size distribution agree well with the theoretical equilibrium metal distributions. [ABSTRACT FROM AUTHOR]

Skin aging may be divided into photoaging and intrinsic aging. The purpose of this study was to investigate the effects of 12-O-tetradecanoyl-phorbol-13-acetate and sodium lauryl sulfate on the production and expression of cytokines and proto-oncogenes in photoaged and intrinsically aged skin, compared with young skin. Keratinocytes were taken from newborns, young adults in their twenties, and from the forearm and thigh of volunteers in their fifties and seventies. Interleukin-1α and -6, and interleukin-1 receptor antagonist, c-fos and c-myc were measured after cultured keratinocytes had been treated with 12-O-tetradecanoyl-phorbol-13-acetate and sodium lauryl sulfate. There has been no report concerning the dependence of cytokine production by sodium lauryl sulfate upon photoaging and intrinsic aging. This study also involves the first investigation of the effects of aging on c-myc expression by 12-O-tetradecanoyl-phorbol-13-acetate treatment. Cytokine production decreased markedly with age. These results suggest the progressive decline of cellular function with age. The ratio of cytokine production in the irritant-treated group compared with that in the control group showed a different pattern in photoaging and intrinsic aging. With the significant difference between photoaging and intrinsic aging, T/C ratio decreased in interleukin-1α and interleukin-1 receptor antagonist upon aging, whereas it increased in interleukin-6. S/C ratio was uniquely elevated on photoaged skin in the 50 y age group. It is suggested that photoaged skin shows an exaggerated reaction to surfactant. Compared with the control, c-fos expression in 12-O-tetradecanoyl-phorbol-13-acetate-treated keratinocytes decreased with age in the thigh, but increased in the photoaged skin of forearm. The increased c-fos expression in 12-O-tetradecanoyl-phorbol-13-acetate-treated keratinocytes could be relevant for the predisposition of photoaged keratinocytes to malignant transformation. [ABSTRACT FROM AUTHOR]

[Display omitted] • We investigated a systematic design and remediation of real U-contaminated soil. • Self-disposal of the treated soil was possible, based on the less than 1.0 Bq·g−1. • Treatment of U-contaminated soil was a practical, judging from economic analysis. This study investigated, from practical and engineering perspectives, a systematic design and its ability to remediate real U-contaminated soil, with the aim of assessing the performance of a zero liquid discharge system for treating wastewater from a soil-washing process. Specifically, we carried out a purification process for U-contaminated soil and its wastewater; the proposed method consisted of U(VI) precipitation, solid–liquid separation with a filter-press, and distillation of the filtrate on the basis of U(VI) concentration. Experimental results indicated complete separation of uranium from the contaminated soil. Self-disposal of the treated soil was possible because it contained uranium at a concentration less than 1.0 Bq·g−1, which the International Atomic Energy Agency has suggested as the clearance level for radionuclides. In terms of the zero liquid discharge system, the distillation process enabled not only water reuse of the filtrate after solid–liquid separation but also self-disposal of high-purity Na 2 SO 4 in the residues of the distilled filtrate. According to a comparison of the economic analysis between direct disposal and the application of a remediation process to treat U-contaminated soil, the proposed comprehensive zero liquid discharge system for the treatment of U-contaminated soil is a practical and feasible option. We anticipate that the valuable experimental results and implications in this study will play a significant role in both academia and industry given the demonstration of design and applicability of the proposed zero liquid discharge system to treat wastewater generated from real U-contaminated soil. [ABSTRACT FROM AUTHOR]

We report a method for preparing uranium trichloride, UCl3, by reacting ZnCl2 with U in a molten LiCl-KCl eutectic salt at 500 °C. Cyclic voltammetry indicated the formation of UCl3 as the reaction proceeded. After 30 h, the reaction was terminated and the final product was confirmed to contain 13.2 wt% UCl3-LiCl-KCl salt by the ICP-OES method. [ABSTRACT FROM AUTHOR]

We report the feasibility of Zn as a liquid cathode in pyroprocessing for the recovery of U. U-Zn alloy formation was observed using electrochemical techniques in a molten LiCl-KCl eutectic containing UCl and ZnCl at 500 °C. Cyclic voltammetry showed two cathodic peaks, confirming the formation of two U-Zn alloys. The Gibbs energy of each U-Zn alloy was estimated by OCV measurement. Potentiostatic electrolysis was employed to confirm the deposition of U on Zn-coated W electrode; the resulting alloys, UZn and UZn, were characterized by X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

Introduction Among non-ablative devices for wrinkle reduction and skin laxity, long pulsed 1064 nm Nd: YAG laser ( LPND) has considerable effectiveness. It can penetrate to deep dermis due to its longer wavelength. This study assesses the efficacy and safety of LPND applying new parameters for skin rejuvenation in Korean subjects. Methods A prospective randomized split-faced study was done ( n = 20). Half of the face was treated with three passes of LPND at a spot size of 12 mm, 20-24 J/cm2 fluence, 12 ms width, and frequency of 2 Hz, for three sessions, every four weeks. Outcomes were measured by wrinkle evaluation of blinded investigators, subjects' self-assessment, objective measurements of elasticity, and skin biopsy. Results Four weeks after the final treatment sessions, the average wrinkle grades of the treated side were reduced by 45.1%. Skin elasticity was significantly increased. The increment of collagen and elastic fiber in papillary dermis was confirmed histologically. No adverse reaction was reported. Pain on the treated side was mild without needing anesthesia. Discussion The authors studied new parameters for LPND for improvement of wrinkles and skin laxity with fewer treatment sessions without serious complications. Histologic findings corresponded to clinical improvement. Conclusion New parameters of LPND can achieve wrinkle improvement with few side effects. [ABSTRACT FROM AUTHOR]

The article discusses a microarray analysis of skin samples obtained from subjects with sensitive or non-sensitive skin. Topics discussed include findings suggesting that adiponectin (ADIPOQ) is one of the downregulated genes in sensitive skin, a small interfering RNA-mediated knockdown of the ADIPOQ gene in vitro conducted to examine the role of ADIPOQ in the pathogenesis of sensitive skin and the need for further genetic studies to address whether reduced ADIPOQ production is inherited.

Summary Background Sensitive skin represents hyperactive sensory symptoms showing exaggerated reactions in response to internal stimulants or external irritants. Although sensitive skin is a very common condition affecting an estimated 50% of the population, its pathophysiology remains largely elusive, particularly with regard to its metabolic aspects. Objective The objective of our study was to investigate the pathogenesis of sensitive skin. Methods We recruited healthy participants with ‘sensitive’ or ‘non-sensitive’ skin based on standardized questionnaires and 10% lactic acid stinging test, and obtained skin samples for microarray analysis and subsequent experiments. Results Microarray transcriptome profiling revealed that genes involved in muscle contraction, carbohydrate and lipid metabolism, and ion transport and balance were significantly decreased in sensitive skin. These altered genes could account for the abnormal muscle contraction, decreased ATP amount in sensitive skin. In addition, pain-related transcripts such as TRPV1, ASIC3 and CGRP were significantly up-regulated in sensitive skin, compared with non-sensitive skin. Conclusions Our findings suggest that sensitive skin is closely associated with the dysfunction of muscle contraction and metabolic homeostasis. [ABSTRACT FROM AUTHOR]

Abstract: Background: β-Catenin, the transducer of Wnt signaling, is critical for the development and growth of hair follicles. In the absence of Wnt signals, cytoplasmic β-catenin is phosphorylated by glycogen synthase kinase (GSK)-3 and then degraded. Therefore, inhibition of GSK-3 may enhance hair growth via β-catenin stabilization. Valproic acid is an anticonvulsant and a mood-stabilizing drug that has been used for decades. Recently, valproic acid was reported to inhibit GSK-3β in neuronal cells, but its effect on human hair follicles remains unknown. Objectives: To determine the effect of VPA on human hair growth. Methods: We investigated the effect of VPA on cultured human dermal papilla cells and outer root sheath cells and on an in vitro culture of human hair follicles, which were obtained from scalp skin samples of healthy volunteers. Anagen induction by valproic acid was evaluated using C57BL/6 mice model. Results: Valproic acid not only enhanced the viability of human dermal papilla cells and outer root sheath cells but also promoted elongation of the hair shaft and reduced catagen transition of human hair follicles in organ culture model. Valproic acid treatment of human dermal papilla cells led to increased β-catenin levels and nuclear accumulation and inhibition of GSK-3β by phosphorylation. In addition, valproic acid treatment accelerated the induction of anagen hair in 7-week-old female C57BL/6 mice. Conclusions: Valproic acid enhanced human hair growth by increasing β-catenin and therefore may serve as an alternative therapeutic option for alopecia. [Copyright &y& Elsevier]

Abstract: The pyroprocessing which uses a dry method to recycle spent oxide fuel generates a waste LiCl salt containing radioactive elements. To reuse LiCl salt, the radioactive impurities has to be separated by the purification process such as layer-melt crystallization. To enhance impurity separation efficiency, it is important to understand the inclusion mechanism of impurities within the LiCl crystal. Herein, we report the inclusion properties of impurities in LiCl crystals. First of all, the substitution enthalpies of Cs+, Sr2+, and Ba2+ impurities with 0–6at% in LiCl crystal were evaluated via first-principles calculations. Also, the molten LiCl containing 1mol of Cs+, Sr2+, and Ba2+ impurities was crystallized through the experimental layer-melt crystallization method. These substitution enthalpy and experiment clarify that a high substitution enthalpy should result in the high separation efficiency for an impurity. Furthermore, we find that the electron density map gives a clue to the mechanism for inclusion of impurities into LiCl crystal. [Copyright &y& Elsevier]

Abstract: Background: Glycosaminoglycans (GAGs) have various structural and physiological regulatory functions in skin, including tissue water maintenance, due to their high water-holding capacity. Objective: To investigate changes of GAGs during intrinsic aging and photoaging of human skin and their correlations with water content. Methods: Samples of sun-protected buttock and sun-exposed forearm skin were obtained from young male (21–30years, n =8) and female (20–33years, n =8) subjects, as well as old male (70–78years, n =8) and female (70–80years, n =8) subjects, and their epidermal and dermal contents of hyaluronic acid (HA), total sulfated GAG (tsGAG), total uronic acid (tUA), and tissue water were measured. HA content was determined by enzyme-linked immunosorbent assay using HA-binding protein, tsGAG by the sulfated GAG assay kit using 1,9-dimethylmethylene blue, tUA by carbazole reaction, and tissue water by subtraction of tissue dry weight from wet weight. Results: In the buttock, HA was higher in dermis than in epidermis, while tsGAG and tUA were higher in epidermis. In intrinsically aged buttock, epidermal HA and dermal tsGAG and tUA decreased. However, when analyzed for each gender, epidermal tsGAG, tUA, and tissue water decreased only in females. Forearm/buttock ratios of each molecule were compared for determination of photoaging-dependent changes. Forearm/buttock ratios of HA, tsGAG, tUA, and tissue water increased in aged dermis, but showed no change in aged epidermis. When analyzed for each gender, ratios of epidermal HA and tissue water increased only in aged females, while ratios of epidermal tsGAG, tUA, and tissue water decreased only in aged males. Correlations of water content with HA, tsGAG, and tUA were found in epidermis, but not with tsGAG in dermis. Conclusion: These intrinsic aging- and photoaging-dependent GAG changes and their correlations with water content provide new insights into the pathophysiology of dry skin in the elderly. [Copyright &y& Elsevier]

Abstract: Background: Thrombospondin-1 (TSP-1) is a matricellular glycoprotein and recognized as an inhibitor of angiogenesis and an activator of transforming growth factor-β (TGF-β). Although TSP-1 expression has been shown to be regulated by various stimuli including UV in some types of cell, more work need to be done to understand the regulation of TSP-1 expression and its functional significances in many other types of cell. Objective: In this study, we investigated the effect of UV on TSP-1 expression in human skin dermis and dermal fibroblasts and the role of TSP-1 on the type I procollagen expression after UV exposure. Methods: Human buttock skin and human dermal fibroblasts were irradiated with UV. The mRNA and the protein levels of TSP-1 or type I procollagen were measured by real-time polymerase chain reaction and Western blotting, respectively. Results: We found that UV irradiation increased TSP-1 expression at the mRNA and protein levels in human skin dermis and dermal fibroblasts. UV-induced TSP-1 expression was greatly suppressed by inhibition of the PI3K, Akt, or mTOR pathways. The inhibition of TSP-1 activity by a blocking peptide or suppression of TSP-1 expression by specific TSP-1 small interfering RNA augmented the UV-induced decrease of type I procollagen expression. Conclusion: Our results suggest that UV-induced TSP-1 plays an important role on alleviating and/or recovering the type I procollagen expression downregulated by UV in human dermal fibroblasts. [Copyright &y& Elsevier]

The article discusses the study that determined roles played by activin A receptor type 1C (ACVR1C) and its ligand in relation to sensitive skin. Findings discussed include significant decrease in ACVR1C messenger ribonucleic acid (mRNA) and protein in sensitive skin in comparison to non-sensitive skin, strong expression of ACVR1C in non-sensitive skin, particularly in muscle tissues, and excessive calcium influx reduced by ligand Nodal in ACVR1C-knockdown cells exposed to calcium ionophore.

Abstract: Although many studies have been performed to elucidate the molecular consequences of ultraviolet irradiation, little is known about the effect of natural products. Ultraviolet irradiation is widely considered to be an environmental stress. Here we investigated the effect of erythrodiol-3-acetate on the expressions of MMP-1,2 in cultured human skin fibroblasts. Erythrodiol-3-acetate was isolated from the stems of Styrax japonica (Styracaceae). Erythrodiol-3-acetate reduced the expression of MMP-1 but not MMP-2, at the mRNA and protein levels in a dose-dependent manner by ultraviolet irradiation. Taken together, our results suggest that erythrodiol-3-acetate an important role in the reduction of MMP-1 induction by ultraviolet irradiation. [Copyright &y& Elsevier]

Background: Minoxidil has been widely used to treat androgenetic alopecia, but little is known about its pharmacological activity or about the identity of its target cells in hair follicles. We hypothesized that minoxidil has direct effects on the proliferation and apoptosis of dermal papilla cells (DPCs) of human hair follicle. Objective: To elucidate the mechanism of topical minoxidil action in terms of stimulating hair growth. Methods: We evaluated cell proliferations in cultured DPCs by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and measured the expressions of extracellular signal-regulated kinase (ERK), Akt, Bcl-2, and Bax by Western blot. We also measured elongation of hair follicles in organ culture. Results: Minoxidil significantly increased the proliferation of DPCs. The levels of ERK phosphorylation and of phosphorylated Akt increased significantly 1 h post-treatment; percentage increase of ERK phosphorylation was 287% at 0.1 μM and 351% at 1.0 μM of minoxidil, and that of Akt phosphorylation was 168% at 0.1 μM and 257% at 1.0 μM of minoxidil. 1.0 μM of minoxidil increased Bcl-2 expression over 150%, while 1.0 μM of minoxidil decreased Bax expression by more than 50%. Moreover, a significant elongation of individual hair follicles in organ culture was observed after adding minoxidil. Conclusion: Minoxidil promotes the survival of human DPCs by activating both ERK and Akt and by preventing cell death by increasing the ratio of Bcl-2/Bax. We suggest that minoxidil stimulates the growth of human hairs by prolonging anagen through these proliferative and anti-apoptotic effects on DPCs. [Copyright &y& Elsevier]

Epidermal Langerhans cells are potent antigen-presenting cells in the epidermis. The establishment of a cryopreservation method for human Langerhans cells would greatly contribute to our ability to successfully conduct various experiments dealing with Langerhans cells. Since Langerhans cells are known to be sensitive to cold injury, there have been no reports concerning the cryopreservation of Langerhans cells. We have investigated the effect of cryopreservation on the function and phenotype of human Langerhans cells. Langerhans cells from human foreskins were isolated with the immunomagnetic microbead method using monoclonal antibodies for CD1a. Langerhans cells were cryopreserved in the presence of dimethylsulfoxide (DMSO) 10% and fetal calf serum 90%. Cryopreserved Langerhans cells were phenotypically assessed by flowcytometry using monoclonal antibodies to HLA-DR and CD1a. The ultrastructures of the Langerhans cells were compared using electron microscopy. An autologous T cell stimulation test was performed to compare the functions of cryopreserved Langerhans cells and fresh Langerhans cells. The viability of the cryopreserved Langerhans cells was able to be maintained at more than 90%. Cryopreserved Langerhans cells expressed high levels of HLA-DR and CD1a antigens and stimulated autologous T cells to an extent almost identical to that obtained from fresh Langerhans cells. These findings indicate that the cryopreservation of human Langerhans cells could lead to a breakthrough in various experiments dealing with human Langerhans cells. [Copyright &y& Elsevier]

Sphingolipid metabolites regulate many aspects of cell growth and differentiation. However, the effects of sphingolipids on the growth and melanogenesis of human melanocytes are not known. In the present study, we investigated the effects of sphingolipid metabolites and the possible signalling pathways involved in human melanocytes. Our data show that C2-ceramide inhibits cell growth in a dose-dependent manner, whereas sphingosine-1-phosphate (SPP) has no effect. Moreover, we observed that the melanin content of the cells was significantly decreased by C2-ceramide. The pigmentation-inhibiting effect of C2-ceramide at 1–10 μM was stronger than that of kojic acid, tested at 1–100 μM. The tyrosinase activity of cell extracts was reduced by C2-ceramide treatment. However, in the cell-free system, C2-ceramide could not suppress tyrosinase, whereas kojic acid directly inhibited tyrosinase. These results suggest that C2-ceramide decreases the pigmentation of melanocytes indirectly regulating tyrosinase. Furthermore, we found that C2-ceramide decreased the protein expression of microphthalmia-associated transcription factor (MITF), which is required for tyrosinase expression. To identify the signalling pathway of ceramide, we studied the ability of C2-ceramide to influence extracellular signal-regulated protein kinase (ERK) and Akt/protein kinase B (PKB) activation. C2-ceramide induced a delayed activation of ERK (>1 h) and a much later activation of Akt/PKB (>3 h) in human melanocytes. In addition, the specific inhibition of the ERK and the Akt signalling pathways by PD98059 and LY294002, respectively, increased melanin synthesis. Thus, it seems that sustained ERK and Akt activation may lead to the suppression of cell growth and melanogenesis. [Copyright &y& Elsevier]

Human macrophage metalloelastase is a member of the matrix metalloproteinase family and is involved in degradation of elastin. We investigated the ultraviolet modulation of human macrophage metalloelastase in human skin in vivo . Ultraviolet induced human macrophage metalloelastase mRNA maximally (11.9-fold) within 16 h post-ultraviolet in human skin. This induction of human macrophage metalloelastase by ultraviolet was inhibited by pretreatment with the antioxidant N-acetyl cystein (20%) and vitamin E (5%) by an average of 54% and 47%, respectively, in human skin in vivo . Ultraviolet (30 mJ per cm2 ) and phorbol ester (12-O-tetradecanoyl-phorbol-13-acetate, 50 nM) treatment increased expression of human macrophage metalloelastase mRNA and protein in the cultured human dermal fibroblasts, but not in the keratinocytes. Chronically sun-exposed human skin expressed significant amounts of human macrophage metalloelastase protein, which colocalized with the material of solar elastosis, whereas there was little expression in sun-protected skin of the same individuals. This study demonstrates that ultraviolet irradiation increases human macrophage metalloelastase expression in human skin in vivo , possibly in macrophages and fibroblasts, and ultraviolet-induced expression of human macrophage metalloelastase can be inhibited by antioxidant (N-acetyl cystein and vitamin E) pretreatment. Association of human macrophage metalloelastase with elastotic material suggests that it may play an important role in the development of solar elastosis, the hallmark of sun-induced damage in human skin in vivo . [ABSTRACT FROM AUTHOR]

UV light is absorbed in the epidermis and induces sunburn cell formation. It has been reported that HSP70 increases the UVB resistance of cell lines by in vitro experiments using various cell lines. In this study, hsp70.1−/− KO mouse was used in order to study the role of HSP70 after UVB irradiation. Western blotting showed a decreased level of HSP70 in hsp70.1−/− KO mouse compared with wild type FVB mouse. Six h after UVB irradiation, there were no significant histologic differences between the hsp70.1−/− KO mouse and the wild type FVB mouse. A similar degree of nuclear swelling was observed. However, there were significant differences at 12 and 24 h after UVB irradiation. After 12 h, a few apoptotic cells were observed in the wild type mouse, but a large number of cells were apoptotic in the hsp70.1−/− KO mouse. After 24 h, the epidermis of the wild type FVB mouse was relatively intact, but almost the entire epidermis was necrotic in the hsp70.1−/− KO mouse. These results showed that epidermal injury of hsp70.1−/− KO mouse was much more severe than that of wild type mouse although initial changes are similar in both species of mice. These results suggest that susceptibility of hsp70.1−/− KO mouse to UVB irradiation may originate from a defect in the repair mechanism. This HSP deficient model may be useful in studies of the effects of tissue injury that relate to the impaired tissue repair mechanisms. [Copyright &y& Elsevier]

Scrubbing off the stratum corneum with a rough towel after soaking in warm water is a bathing custom unique to Korea. However, Korean dermatologists have advised against this practice due to the potential harm that it may cause, though there is little data to support this advice. This study aimed to evaluate the changes in biophysical characteristics after such mechanical injury of stratum corneum, as reflected by water-holding capacity, stratum corneum barrier function, and stratum corneum turnover time (SCTT). 10 Korean female volunteers (aged 19–34 years) were enrolled in this study to investigate the acute effects and 32 volunteers (aged 19–49 years) the chronic effects. After soaking in warm water (36 °C) for 5 min, the flexor surfaces of the forearms were scrubbed with a rough towel. The volunteers' forearms were divided into 4 compartments, and each compartment was scrubbed 0, 5, 10, and 15×, respectively. After a single injury of the stratum corneum, there was an initial decrease in water-holding capacity until 6 h. Thereafter, it increased until day (D) 3, when it began to descend to the normal range. The transepidermal water loss (TEWL) values also peaked at D2 and declined thereafter. However, there were no changes in either water-holding capacity or skin barrier function, and only the SCTT was significantly shortened, after chronic injury of the stratum corneum. [ABSTRACT FROM AUTHOR]

This is a comprehensive study of the changes in major antioxidant enzymes and antioxidant molecules during intrinsic aging and photoaging processes in the epidermis and dermis of human skin in vivo . We show that the activities of superoxide dismutase and glutathione peroxidase are not changed during these processes in human skin in vivo . Interestingly, the activity of catalase was significantly increased in the epidermis of photoaged (163%) and naturally aged (118%) skin (n = 9), but it was significantly lower in the dermis of photoaged (67% of the young skin level) and naturally aged (55%) skin compared with young (n = 7) skin. The activity of glutathione reductase was significantly higher (121%) in naturally aged epidermis. The concentration of α-tocopherol was significantly lower in the epidermis of photoaged (56% of young skin level) and aged (61%) skin, but this was not found to be the case in the dermis. Ascorbic acid levels were lower in both epidermis (69% and 61%) and dermis (63% and 70%) of photoaged and naturally aged skin, respectively. Gluta thione concentrations were also lower. Uric acid did not show any significant changes. Our results suggest that the components of the antioxidant defense system in human skin are probably regulated in a complex manner during the intrinsic aging and photoaging processes. [ABSTRACT FROM AUTHOR]

To the best of our knowledge, no study has been conducted to date to directly compare the collagen metabolism of photoaged and naturally aged human skin. In this study, we compared collagen synthesis, matrix metalloproteinase-1 levels, and gelatinase activity of sun-exposed and sun-protected skin of both young and old subjects. Using northern blot analysis, immunohistochemical stain, and Western blot analysis, we demonstrated that the levels of procollagen type I mRNA and protein in photoaged and naturally aged human skin in vivo are significantly lower than those of young skin. Furthermore, we demonstrated, by northern blot analysis, that the procollagen α1(I) mRNA expression of photoaged skin is much greater than that of sun-protected skin in the same individual. In situ hybridization and immunohistochemical stain were used to show that the expression of type I procollagen mRNA and protein in the fibroblasts of photoaged skin is greater than for naturally aged skin. In addition, it was found, by Western blot analysis using protein extracted from the dermal tissues, that the level of procollagen type I protein in photoaged skin is lower than that of naturally aged skin. The level of matrix metalloproteinase-1 protein and the activity of matrix metalloproteinase-2 were higher in the dermis of photoaged skin than in naturally aged skin. Our results suggest that the natural aging process decreases collagen synthesis and increases the expression of matrix metalloproteinases, whereas photoaging results in an increase of collagen synthesis and greater matrix metalloproteinase expression in human skin in vivo . Thus, the balance between collagen synthesis and degradation leading to collagen deficiency is different in photoaged and naturally aged skin. [ABSTRACT FROM AUTHOR]

Photoaged skin contains elastotic materials in the upper reticular dermis. This phenomenon is commonly known as solar elastosis. Little is known about the mechanisms leading to the accumulation of elastotic materials in photoaged skin, however. In this study, it was demonstrated that ultraviolet irradiation induced tropoelastin mRNA expression in the keratinocytes of human skin in vivo and also in cultured human keratinocytes by in situ hybridization and reverse transcriptase polymerase chain reaction. It was also shown by northern blot analysis (n = 5) that there were increased tropoelastin mRNA levels in the forearm (sun-exposed) skin of elderly persons, compared with upper-inner arm (sun-protected) skin of the same individuals. As demonstrated by in situ hybridization compared to sun-protected skin (upper-inner arm) (n = 5), tropoelastin mRNA expression in photoaged skin was higher in keratinocytes as well as in fibroblasts. Therefore, our results suggest that keratinocytes are another source of tropoelastin production after acute and chronic ultraviolet irradiation in human skin in vivo. [ABSTRACT FROM AUTHOR]