Low-level red plus near infrared lights combination induces expressions of collagen and elastin in human skin in vitro.

OBJECTIVE: Light therapy has attracted medical interests as a safe, alternative treatment for photo-ageing and photo-damaged skin. Recent research suggested the therapeutic activity of red and infrared (IR) lights may be effective at much lower energy levels than those used clinically. This study was to evaluate the efficacy of low-level red plus near IR light emitting diode (LED) combination on collagen and elastin and ATP production. METHODS: Human dermal fibroblasts or skin tissues were irradiated daily by red (640 nm) plus near IR (830 nm) LED lights combination at 0.5 mW/cm2 for 10 minutes (0.3 J/cm2 ). qPCR, ELISAs or histology were used to determine the gene and protein expressions. Fluorescent measurement was used to assess crosslinks of collagen and elastic fibres. ATP production was evaluated by ATP assay. RESULTS: Treatment of human fibroblast cell cultures with low-level red plus near IR lights combination was found to significantly increase LOXL1, ELN and COL1A1 and COL3A1 gene expressions as well as the synthesis of the procollagen type I and elastin proteins. Treating human skin explants with low-level red plus near IR lights combination similarly induced significant increases in the same gene expressions, type III collagen and elastic fibre formation and crosslinks. ATP production was increased in human dermal fibroblasts after red plus near IR lights combination treatment. CONCLUSION: Low-level red plus near IR lights combination stimulated the production of collagen and elastin production associated with anti-ageing benefits. These findings suggest that low-level red plus near IR LED light combination may provide an effective treatment opportunity for people with photo-aged skin.

OBJECTIF: La luminothérapie a suscité des intérêts médicaux en tant que traitement alternatif sûr pour la photo-vieillissement et la peau endommagée. Des recherches récentes ont suggéré que L'activité thérapeutique des feux rouges et infrarouges (IR) pourrait être efficace à des niveaux d'énergie beaucoup plus faibles que ceux utilisés en clinique. Cette étude avait pour but d'évaluer l'efficacité de la combinaison de diodes électroluminescentes (DEL) rouges de faible intensité et de diodes électroluminescentes (IR) sur la production de collagène, d'élastine et d'ATP. MÉTHODES: Les fibroblastes dermiques humains ou les tissus cutanés ont été irradiés quotidiennement par une combinaison de feux rouges (640nm) et de feux à DEL proches de l'IR (830nm) à 0,5mW/cm2 pendant 10minutes (0,3J/cm2). qPCR, ELISA ou histologie ont été utilisés pour déterminer les expressions géniques et protéiques. Des mesures fluorescentes ont été utilisées pour évaluer les liens croisés du collagène et des fibres élastiques. La production d'ATP a été évaluée au moyen d'un essai ATP. RÉSULTATS: Le traitement de cultures de cellules de fibroblastes humaines avec une combinaison rouge de faible intensité et proche des lumières IR a permis d'augmenter significativement les expressions des gènes LOXL1, ELN et COL1A1 et COL3A1, ainsi que la synthèse des protéines de procollagène de type I et d'élastine. Le traitement des explants de peau humaine avec une combinaison rouge de bas niveau et proche des lumières IR a également induit des augmentations significatives dans les mêmes expressions géniques, la formation de collagène de type III et de fibres élastiques et les liaisons croisées. La production d'ATP a augmenté dans les fibroblastes dermiques humains après le traitement combiné rouge et proche des feux IR. CONCLUSION: L'association du rouge de bas niveau et des lumières infrarouges a stimulé la production de collagène et d'élastine associée aux bienfaits de l'antivieillissement. Ces résultats suggèrent que la combinaison de faible intensité de rouge plus proche de la lumière IR LED peut fournir une opportunité de traitement efficace pour les personnes ayant la peau photo-âgée.

Greater efficacy of SPF 100+ sunscreen compared with SPF 50+ in sunburn prevention during 5 consecutive days of sunlight exposure: A randomized, double-blind clinical trial.

BACKGROUND: Beach vacations are high-risk settings for overexposure to ultraviolet radiation. OBJECTIVE: To compare the sunburn protective efficacy of SPF 50+ and SPF 100+ sunscreens under actual use at the beach. METHODS: A prospective, randomized, double-blind, single-center, split-body/face study of 55 healthy individuals. Each participant applied both sunscreens to randomized sides of the face/body for up to 5 consecutive days. Blinded clinical evaluation of erythema by a single grader and objective instrumental assessments, colorimetry, and diffuse reflectance spectroscopy were performed the morning after each sun exposure. RESULTS: After 5 days, 31 (56%) participants had more sunburn on the SPF 50+ side compared to 4 (7%) on the SPF 100+ side. Overall, mean erythema intensity showed statistically significantly less erythema on the SPF 100+ side compared with the SPF 50+ side. The first observation of sunburn exclusively on the SPF 50+ side occurred after 1 day of sun exposure, whereas that for SPF 100+ occurred after 3 days of sun exposure. LIMITATIONS: Only initial sunscreen application was monitored, only 1 participant with skin phototype I was recruited, and participants were recruited from a local beach area. CONCLUSION: SPF 100+ was significantly more effective in protecting against ultraviolet radiation-induced erythema and sunburn than SPF 50+ in actual use in a beach vacation setting.

A novel rat robot controlled by electrical stimulation of the nigrostriatal pathway.

OBJECTIVE: Artificial manipulation of animal movement could offer interesting advantages and potential applications using the animal's inherited superior sensation and mobility. Although several behavior control models have been introduced, they generally epitomize virtual reward-based training models. In this model, rats are trained multiple times so they can recall the relationship between cues and rewards. It is well known that activation of one side of the nigrostriatal pathway (NSP) in the rat induces immediate turning toward the contralateral side. However, this NSP stimulation-induced directional movement has not been used for the purpose of animal-robot navigation. In this study, the authors aimed to electrically stimulate the NSP of conscious rats to build a command-prompt rat robot. METHODS: Repetitive NSP stimulation at 1-second intervals was applied via implanted electrodes to induce immediate contraversive turning movements in 7 rats in open field tests in the absence of any sensory cues or rewards. The rats were manipulated to navigate from the start arm to a target zone in either the left or right arm of a T-maze. A leftward trial was followed by a rightward trial, and each rat completed a total of 10 trials. In the control group, 7 rats were tested in the same way without NSP stimulation. The time taken to navigate the maze was compared between experimental and control groups. RESULTS: All rats in the experimental group successfully reached the target area for all 70 trials in a short period of time with a short interstimulus interval (< 0.7 seconds), but only 41% of rats in the control group reached the target area and required a longer period of time to do so. The experimental group made correct directional turning movements at the intersection zone of the T-maze, taking significantly less time than the control group. No significant difference in navigation duration for the forward movements on the start and goal arms was observed between the two groups. However, the experimental group showed quick and accurate movement at the intersection zone, which made the difference in the success rate and elapsed time of tasks. CONCLUSIONS: The results of this study clearly indicate that a rat-robot model based on NSP stimulation can be a practical alternative to previously reported models controlled by virtual sensory cues and rewards.

Evaluation of Seasonal Changes in Facial Skin With and Without Acne.

The objective of this study was to compare facial skin of adolescent males with (acne) and without acne (non-acne) over the course of 1 year. At study entry, presence of acne was determined by clinical image analysis (acne n=7, non-acne n=10). Monthly evaluations of skin condition were made using standard and fluorescent imaging, fluorescence spectroscopic analysis, sebum analysis, skin high frequency conductivity (moisture content), transepidermal water loss (TEWL), and sampling of skin bacteria (aerobic and anaerobic). Data were evaluated seasonally. Over the course of the study, subjects in the acne and non-acne groups had no significant increase in their clinical acne score. Sebum production was significantly greater in subjects with acne than in those without for each season examined (P<0.019) and was lowest in the winter and highest in the fall. TEWL was higher in those with acne than without acne across all seasons (P=0.001). Skin moisture in both groups was increased during summer and fall compared with winter (P≤0.016 for both seasons). Subjects with acne had a higher recovery of both aerobic and anaerobic bacteria compared with subjects without acne (P≤0.015). Analysis of cheek skin in the nasal area revealed significantly higher fluorescence (500-800 nm) in image-based and spectroscopic analysis from subjects with acne, suggesting the greater presence of the bacterial metabolite porphyrin in those with acne. In these cohorts of adolescent males, significant differences in sebum production, skin barrier function, moisture content, and microbial load (anaerobic and aerobic) were noted between those with and without acne. Evidence for seasonality was observed, with lower lipid production and reduced barrier function during the winter. More studies to quantify differences in skin lipid components and bacterial species among these cohorts are planned.

Imidazoanthraquinone Derivative as a Surface Passivator for Enhanced and Stable Perovskite Solar Cells.

Hybrid organic-inorganic perovskites have been investigated for their potential to serve in next-generation perovskite solar cells (PSCs). While PSC technology is approaching commercialization, thermal and moisture stabilities remain a concern. Here, we describe the assembly of PSCs using an imidazoanthraquinone derivative (AQ) as a small organic additive to enhance the device performance and stability. Unlike polymer additives, AQ is easy to synthesize and is more economical. AQ was synthesized because it has both carbonyl and imidazole functional groups. The presence of C=O and N-H groups results in coordination interaction with Pb2+ and I- of the perovskite. Addition of the AQ molecule to methylammonium lead iodide leads to the formation of a superior crystalline perovskite film with fewer defects and enhanced stability under humid conditions. The use of optimized perovskite films enhanced device power conversion efficiency (PCE = 17.21%) compared to pristine perovskite (PCE = 13.88%). Unencapsulated optimized devices retained 90% of the initial power conversion efficiency for 30 days at a relative humidity of nearly 35%. The optimized films also exhibited superior thermal stability to that of pristine perovskite films.

Non-invasive assessment of tryptophan fluorescence and confocal microscopy provide information on skin barrier repair dynamics beyond TEWL.

The stratum corneum (SC) serves a primary function of skin barrier and understanding the kinetics of SC formation may provide great insight for skin diagnosis and evaluation of therapies. Besides trans-epidermal water loss (TEWL), few methods have been characterized to assess skin barrier non-invasively in vivo, particularly for dynamic measurements on the same specimen over time. The objective of this study was to characterize alternative non-invasive methods to evaluate the dynamic processes involved in the recovery of normal human SC after total removal. TEWL, tryptophan fluorescence and reflectance confocal microscopy (RCM) were used to determine skin barrier function, cell turnover and epidermal morphology over a period of 10 days after total removal of the SC by tape stripping. The results show a biphasic recovery of TEWL over time, which contrasted with a linear increase of 2.3 µm/day in SC thickness. Tryptophan assessment of cell turnover also demonstrated a biphasic pattern attaining a maximum three to four times the levels of the control site 3 days after injury that slowly returned to baseline and displayed great correlation (R(2)  > 0.95) to viable epidermis thickness that also achieved a maximum about 3 days after injury with an approximate increase of 55%. When plotting the change of TEWL versus SC thickness, a single exponential function is observed [Δ-TEWL = 55 exp (-0.157×)] which contrasts with other proposed models. These methods were able to present rates for SC recovery processes beyond skin barrier (TEWL) that may provide new insights on kinetics of barrier formation for evaluation of skin conditions and treatments.

Photo-Charging of Li(Ni0.65Co0.15Mn0.20)O2 Lithium-Ion Battery Using Silicon Solar Cells.

This study reports an integrated device in which a lithium-ion battery (LIB) and Si solar cells are interconnected. The LIB is fabricated using the Li(Ni0.65Co0.15Mn0.20)O2 (NCM622) cathode and the Li4Ti5O12 (LTO) anode. The surface and shape morphologies of the NCM and LTO powders were investigated by field emission scanning electron microscopy (FE-SEM). In addition, the structural properties were thoroughly examined by X-ray diffraction (XRD). Further, their electrochemical characterization was carried out on a potentiostat. The specific discharge capacity of the NCM cathode (half-cell) was 188.09 mAh/g at 0.1 C current density. In further experiments, the NCM-LTO full-cell has also shown an excellent specific capacity of 160 mAh/g at a high current density of 1 C. Additionally, the capacity retention was outstanding, with 99.63% at 1 C after 50 cycles. Moreover, to meet the charging voltage requirements of the NCM-LTO full-cell, six Si solar cells were connected in series. The open-circuit voltage (VOC) and the short-circuit photocurrent density (JSC) for the Si solar cells were 3.37 V and 5.42 mA/cm2. The calculated fill factor (FF) and efficiency for the Si solar cells were 0.796 and 14.54%, respectively. Lastly, the integrated device has delivered a very high-power conversion-storage efficiency of 7.95%.

Synthesis of Superionic Conductive Li1+x+yAlxSiyTi2-xP3-yO12 Solid Electrolytes.

Commercial lithium-ion batteries using liquid electrolytes are still a safety hazard due to their poor chemical stability and other severe problems, such as electrolyte leakage and low thermal stability. To mitigate these critical issues, solid electrolytes are introduced. However, solid electrolytes have low ionic conductivity and inferior power density. This study reports the optimization of the synthesis of sodium superionic conductor-type Li1.5Al0.3Si0.2Ti1.7P2.8O12 (LASTP) solid electrolyte. The as-prepared powder was calcined at 650 °C, 700 °C, 750 °C, and 800 °C to optimize the synthesis conditions and yield high-quality LASTP powders. Later, LASTP was sintered at 950 °C, 1000 °C, 1050 °C, and 1100 °C to study the dependence of the relative density and ionic conductivity on the sintering temperature. Morphological changes were analyzed using field-emission scanning electron microscopy (FE-SEM), and structural changes were characterized using X-ray diffraction (XRD). Further, the ionic conductivity was measured using electrochemical impedance spectroscopy (EIS). Sintering at 1050 °C resulted in a high relative density and the highest ionic conductivity (9.455 × 10-4 S cm-1). These findings corroborate with the activation energies that are calculated using the Arrhenius plot. Therefore, the as-synthesized superionic LASTP solid electrolytes can be used to design high-performance and safe all-solid-state batteries.

Structural properties of lithium thio-germanate thin film electrolytes grown by radio frequency sputtering.

In this study, lithium thio-germanate thin film electrolytes have been successfully prepared by radio frequency (RF) magnetron sputtering deposition in Ar gas atmospheres. The targets for RF sputtering were prepared by milling and pressing appropriate amounts of the melt-quenched starting materials in the nLi(2)S + GeS(2) (n = 1, 2, and 3) binary system. Approximately 1 µm thin films were grown on Ni coated Si (Ni/Si) substrates and pressed CsI pellets using 50 W power and 25 mtorr (∼3.3 Pa) Ar gas pressures to prepare samples for Raman and Infrared (IR) spectroscopy, respectively. To improve the adhesion between the silicon substrate and the thin film electrolyte, a sputtered Ni layer (∼120 nm) was used. The surface morphologies and thickness of the thin films were determined by field emission scanning electron microscopy (FE-SEM). The structural properties of the starting materials, target materials, and the grown thin films were examined by X-ray diffraction (XRD), Raman, and IR spectroscopy.

Development of a Self-Charging Lithium-Ion Battery Using Perovskite Solar Cells.

This study demonstrates the use of perovskite solar cells for fabrication of self-charging lithium-ion batteries (LIBs). A LiFePO4 (LFP) cathode and Li4Ti5O12 (LTO) anode were used to fabricate a LIB. The surface morphologies of the LiFePO4 and Li4Ti5O12 powders were examined using field emission scanning electron microscopy. The structural properties of the two powders were investigated using X-ray diffraction. The electrochemical properties of the LiFePO4-Li and Li4Ti5O12-Li half cells and of the full cell were investigated. The LiFePO4-Li4Ti5O12 full cell showed an excellent Coulombic efficiency of 99.3% after 100 cycles. CH3NH3PBI3 (MAPbI3) perovskite solar cells (PSCs) were fabricated using a spin coating technique. A single PSC showed a power conversion efficiency of 12.95%. In order to develop a self-charging system for LIBs, four single PSCs connected in series were used as an LFP-LTO battery. The integrated PSC system showed a power conversion efficiency of 12.44%. The PSC-LIB coupled device showed excellent overall self-charging conversion and a storage efficiency of 9.25%.

Radiative transport in the delta-P1 approximation for semi-infinite turbid media.

We have developed an analytic solution for spatially resolved diffuse reflectance within the deltaP1 approximation to the radiative transport equation for a semi-infinite homogeneous turbid medium. We evaluate the performance of this solution by comparing its predictions with those provided by Monte Carlo simulations and the standard diffusion approximation. We demonstrate that the delta-P1 approximation provides accurate estimates for spatially resolved diffuse reflectance in both low and high scattering media. We also develop a multi-stage nonlinear optimization algorithm in which the radiative transport estimates provided by the delta-P1 approximation are used to recover the optical absorption (microa), reduced scattering (micros'), and single-scattering asymmetry coefficients (g1) of liquid and solid phantoms from experimental measurements of spatially resolved diffuse reflectance. Specifically, the delta-P1 approximation can be used to recover microa, micros', and g1 with errors within +/- 22%, +/- 18%, and +/- 17%, respectively, for both intralipid-based and siloxane-based tissue phantoms. These phantoms span the optical property range 4 < (micros' /microa) < 117. Using these same measurements, application of the standard diffusion approximation resulted in the recovery of microa and micros' with errors o f +/- 29% and +/- 25%, respectively. Collectively, these results demonstrate that the delta-P1 approximation provides accurate radiative transport estimates that can be used to determine accurately the optical properties of biological tissues, particularly in spectral regions where tissue may display moderate/low ratios of reduced scattering to absorption (micros'/microa).

Cross detection for odor of metabolic waste between breast and colorectal cancer using canine olfaction.

Although several studies have been performed to detect cancer using canine olfaction, none have investigated whether canine olfaction trained to the specific odor of one cancer is able to detect odor related to other unfamiliar cancers. To resolve this issue, we employed breast and colorectal cancer in vitro, and investigated whether trained dogs to odor related to metabolic waste from breast cancer are able to detect it from colorectal cancer, and vice versa. The culture liquid samples used in the cultivation of cancerous cells (4T1 and CT26) were employed as an experimental group. Two different breeds of dogs were trained for the different cancer odor each other. The dogs were then tested using a double-blind method and cross-test to determine whether they could correctly detect the experimental group, which contains the specific odor for metabolic waste of familiar or unfamiliar cancer. For two cancers, both dogs regardless of whether training or non-training showed that accuracy was over 90%, and sensitivity and specificity were over 0.9, respectively. Through these results, it was verified that the superior olfactory ability of dogs can discriminate odor for metabolic waste of cancer cells from it of benign cells, and that the specific odor for metabolic waste of breast cancer has not significant differences to it of colorectal cancer. That is, it testifies that metabolic waste between breast and colorectal cancer have the common specific odor in vitro. Accordingly, a trained dogs for detecting odor for metabolic waste of breast cancer can perceive it of colorectal cancer, and vice versa. In order to the future work, we will plan in vivo experiment for the two cancers and suggest research as to what kind of cancers have the common specific odor. Furthermore, the relationship between breast and colorectal cancer should be investigated using other research methods.

Perturbation and differential Monte Carlo methods for measurement of optical properties in a layered epithelial tissue model.

The use of perturbation and differential Monte Carlo (pMC/dMC) methods in conjunction with nonlinear optimization algorithms were proposed recently as a means to solve inverse photon migration problems in regionwise heterogeneous turbid media. We demonstrate the application of pMC/dMC methods for the recovery of optical properties in a two-layer extended epithelial tissue model from experimental measurements of spatially resolved diffuse reflectance. The results demonstrate that pMC/dMC methods provide a rapid and accurate approach to solve two-region inverse photon migration problems in the transport regime, that is, on spatial scales smaller than a transport mean free path and in media where optical scattering need not dominate absorption. The pMC/dMC approach is found to be effective over a broad range of absorption (50 to 400%) and scattering (70 to 130%) perturbations. The recovery of optical properties from spatially resolved diffuse reflectance measurements is examined for different sets of source-detector separation. These results provide some guidance for the design of compact fiber-based probes to determine and isolate optical properties from both epithelial and stromal layers of superficial tissues.

Visible Light Induces Melanogenesis in Human Skin through a Photoadaptive Response.

Visible light (400-700 nm) lies outside of the spectral range of what photobiologists define as deleterious radiation and as a result few studies have studied the effects of visible light range of wavelengths on skin. This oversight is important considering that during outdoors activities skin is exposed to the full solar spectrum, including visible light, and to multiple exposures at different times and doses. Although the contribution of the UV component of sunlight to skin damage has been established, few studies have examined the effects of non-UV solar radiation on skin physiology in terms of inflammation, and limited information is available regarding the role of visible light on pigmentation. The purpose of this study was to determine the effect of visible light on the pro-pigmentation pathways and melanin formation in skin. Exposure to visible light in ex-vivo and clinical studies demonstrated an induction of pigmentation in skin by visible light. Results showed that a single exposure to visible light induced very little pigmentation whereas multiple exposures with visible light resulted in darker and sustained pigmentation. These findings have potential implications on the management of photo-aggravated pigmentary disorders, the proper use of sunscreens, and the treatment of depigmented lesions.

Skin responses to micro scale field size of solar-simulated radiation--preliminary evaluation by reflectance confocal microscopy in vivo.

Erythema and pigment responses of human skin following an acute exposure to ultraviolet radiation (UVR) are frequently used to determine the photosensitivity of the skin. In this study we investigated the responses of the skin to a micro-scale area of UVR exposure (MiR) and compared the responses to a macro-scale area of exposure (MaR). Ten human volunteers were tested with solar-simulated radiation on their upper arm or back using a beam size of 8 mm and 0.2 mm in diameter. The fluence required to produce a minimally perceptible erythema (MED) using the MiR was found to be higher than that for the MaR. The erythema response extended beyond the exposed area and this became pronounced when the beam size was microscopic. Reflectance confocal microscopy in vivo revealed that MiR induced cellular alterations within a confined area of smaller dimensions than the area of exposure. Pigment responses were confined within the areas of cellular damage. The erythema expression of exposed skin recovered faster for the sites receiving MiR even when the applied fluence was higher than the MED for the MaR. Through the use of MiR we were able to visualize spatially dissimilar skin responses of erythema and pigmentation suggesting different cellular mechanisms.

Simultaneous assessment of pulsating and total blood in inflammatory skin lesions using functional diffuse reflectance spectroscopy in the visible range.

We present a simple and cost-effective optical technique for the simultaneous assessment of pulsating and total blood noninvasively in an inflammatory skin lesion. Acquisitions of diffuse reflectance spectra in the visible range at 6 Hz are used to trace the oscillating components of reflectance. Measurements on erythematous lesions from a UV insult show slow changing signal at about 0.1 Hz and heart-driven regular oscillations at about 1 Hz simultaneously. The results demonstrate the potential of the technique in monitoring both pulsating and steady components of the blood in inflammatory lesions of the skin.

Interpreting diffuse reflectance for in vivo skin reactions in terms of chromophores.

The measurement and quantification of skin reactions to insults involves certain assumptions about the relation between intensity of color appearance of the skin and the concentration of endogenous chromophores. The underlying assumption is that the Beer-Lambert law is obeyed, i.e., that a linear relation exists between the absorbance and the concentration of each chromophore and that the total absorbance is the linear superposition of the contributions of each chromophore. In this paper the authors compiled the results from a number of interventions on human skin that result in changes in its appearance and small deviations from the homeostatic state, where the results may be accounted for by a single or multiple chromophores. The validity of the assumptions is found to hold for a limited range of responses. The biological constraints need to be considered in certain cases because as we move away from the homeostatic state, complex biological processes are induced.