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Notes: The cornified envelope (CE) is a thin insoluble structure enveloping corneocytes, and is essential for the barrier function of the stratum corneum (SC). Our previous studies revealed that immature CEs are detected in the outermost layer of SC of barrier-impaired epidermis including the face and in various inflammatory disorders, using a non-invasive method to evaluate CE maturity. However, factors attributable for immaturity of CEs are still unclear. The aim of the present study is to clarify whether immature CEs in the SC have the potential to mature. SC samples, in which immature CEs abundantly exist, were collected from the cheek of healthy volunteers by tape-stripping, and were incubated ex vivo under the humidified air at 37 °C. Then, CE maturity was evaluated by staining with a combination of anti-involucrin and Nile red to detect involucrin antigenicity in the immature CEs and hydrophobicity in the mature CEs, respectively. Ex vivo incubation of the SC resulted in the conversion of immature CEs into mature CEs in terms of loss of involucrin antigenicity and acquisition of hydrophobicity. Application of buffer solutions of various pH onto the SC prior to incubation revealed that maturation of CEs was proceeded at range of pH 5–7, corresponding to intrinsic pH range within the SC. Chelating agents, ethylenediamine-N, N, N′, N′,-tetraacetic acid (EDTA) and ethyleneglycol bis(β-aminoethylether)-N,N,N′,N′-tetraacetic acid (EGTA), and thiol alkylating agents, N-ethylmaleimide and iodoacetamide, inhibited the maturation. Labelled cadaverine as an exogenous substrate for transglutaminase (TGase) could be incorporated into CEs during maturation. Extractable involucrin-like protein detected in the SC samples before incubation concomitantly disappeared with CE maturation, suggesting incorporation of endogenous substrates into the CEs. These results obviously demonstrate that maturation of CEs was mediated by TGase activity in the SC, and that immature CEs found in the outermost face SC have potential to mature by cross-linking of endogenous CE precursors present in the SC. Reduction of environmental humidity during ex vivo incubation of the SC resulted in marked suppression of maturation of CEs, and application of a moisturizer, glycerine, onto the SC replenished the suppression of maturation, suggesting that water content in the SC may affect the TGase reaction in the SC. Therefore, various factors, including a decrease in the water content in the SC, may account for impaired maturation of CEs in the face SC.

Notes: Abstract: IL-1 receptor antagonist (IL-1ra) is a cytokine that competitively binds the IL-1 receptor to antagonize IL-1 activity without any agonist function. Previous experiments indicated that the ratio of IL-1ra to IL-1α in the normal stratum corneum (SC) was much higher in the sunexposed face than in the sun-protected area, upper arms. It was also reported by another laboratory that IL-1ra is increased in the lesional skin of psoriatic patients. This study was designed to measure the contents of IL-1α and IL-1ra in non-lesional and pathological SC obtained from inflammatory skin diseases including psoriasis and non-psoriatic dermatoses such as atopic dermatitis. The SC materials were obtained with a noninvasive tape-stripping method. Their soluble fractions were prepared and assayed for IL-1α and IL-1ra by enzyme-linked immunosorbent assays. As a result we confirmed the previous findings that the ratio of IL-1ra to IL-1α in the normal SC was much higher in the face than in the sun-protected sites, the trunk as well as extremities. Next, we found that IL-1α contents were significantly reduced in the SC samples obtained from inflammatory skin regardless of whether their IL-1ra contents increased or unchanged. Moreover, we noted that an increased ratio of IL-1ra to IL-1α in the SC was not specific to psoriasis, but was also found in other inflammatory skin diseases including atopic dermatitis. This ratio was found to become lower after successful treatment of these skin lesions with topical glucocorticoids. We conclude from these observations that the increased ratio of IL-1ra to IL-1α in the SC is a non-specific phenomenon that can occur in any inflammatory skin diseases regardless of the inflammatory pattern, probably reflecting a skin regulation process against various kinds of inflammation.

Notes: High quality ZnSe layers have been grown by molecular beam epitaxy on dry-etched ZnSe substrates. Surface damage caused by cutting and polishing of the ZnSe substrate was removed by dry etching using BCl3 gas to 10 μm depth. The dry-etched ZnSe substrates exhibited smooth surface morphology and showed excitonic emissions stronger than that from as-polished substrates in photoluminescence (PL) measurements at 11 K. The low-temperature PL spectra obtained from homoepitaxial ZnSe layers grown on the substrates dry etched at the optimum condition showed a strong free-exciton emission at 2.804 eV and a dominant donor-bound exciton emission at 2.798 eV. Since each excitonic emission shows a single peak, the homoepitaxial layers appear to be free from strain.

Notes: Rectifying homojunction have been fabricated in polycrystalline CuInSe2 thin film. The p-n junction diode was obtained by short annealing in nitrogen atmosphere at 450 °C following the ion implantation of nitrogen with the energy and the dose of 50 keV and 1×1015 cm−2, respectively. The properties of the near surface region in the films implanted have been studied by the Raman scattering spectroscopy. The secondary ion mass spectroscopy depth profile of the nitrogens in the CuInSe2 film and the capacitive-voltage characteristics of the rectifying diode have been measured to characterize the junction properties. The photovoltaic characteristics in AM 1.0, 100 mW/cm2 are shown with the efficiency of 0.35%.

Notes: A heated film of hydrogenated amorphous silicon was doped with phosphorus and hydrogen by a 6.0-kV diffused and accelerated beam of ions from rf discharge in a magnetic field, which produced a plasma from phosphine gas containing hydrogen. This doping technique achieved a dark conductivity of 8.7×10−4 (Ω cm−1) at room temperature. The conductivity activation energy was 0.17 eV.

Notes: We describe the design and performance of compact, low-pass electrical filters, suitable for operation at cryogenic temperatures. The filters are two pole LC filters with a cutoff at ≈100 kHz, an attenuation of −24 dB/octave, and a stop band rejection of −80 dB between 5 and 20 MHz. Their function is to suppress rf voltage noise to sensitive cryogenic detectors. The low-pass filters are realized using surface mounted devices on thin PC boards which can be stacked for maximum packing density. Compact modules containing 14 and 35 filters have been developed and installed in the Infrared Telescope in Space. © 1995 American Institute of Physics.

Notes: The modulated photoconductivity technique, a convenient means of measuring the drift mobility of photocarriers, has been applied to investigate carrier transport in hydrogenated amorphous silicon. The frequency resolved spectra of drift mobility that can be obtained from the measurements were analyzed in accordance with a generalized transport model that included possible carrier interactions between localized states through tunneling transitions. Theory suggests that a tunneling-assisted thermalization of nonequilibrium carriers appreciably affects the transport process. The experimental results are reasonably accounted for by the introduced model, leading to quantitative assessments for transport mechanisms. © 2000 American Institute of Physics.