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Malassezia cells stimulate cytokine production by keratinocytes, although this ability differs among Malassezia species for unknown reasons. The aim of this study was to clarify the factors determining the ability to induce cytokine production by human keratinocytes in response to Malassezia species. M. furfur NBRC 0656, M. sympodialis CBS 7222, M. dermatis JCM 11348, M. globosa CBS 7966, M. restricta CBS 7877, and three strains each of M. globosa, M. restricta, M. dermatis, M. sympodialis, and M. furfur maintained under various culture conditions were used. Normal human epidermal keratinocytes (NHEKs) (1 × 105 cells) and the Malassezia species (1 × 106 cells) were co-cultured, and IL-1α, IL-6, and IL-8 mRNA levels were determined. Moreover, the hydrophobicity and β-1,3-glucan expression at the surface of Malassezia cells were analyzed. The ability of Malassezia cells to trigger the mRNA expression of proinflammatory cytokines in NHEKs differed with the species and conditions and was dependent upon the hydrophobicity of Malassezia cells not β-1,3-glucan expression. [ABSTRACT FROM AUTHOR]

According to recent studies, stem cells are found in various tissues in our bodies. It has been reported that stem cells can reside in the skin tissues, including the epidermis, dermis, hair follicles and subcutaneous tissues. Homeostasis of the skin is maintained because these stem cells collaborate with each other to form new cells. We previously identified the CD271(p75 NTR)+ cell as a stem cell that was present in the epidermis, dermis and subcutaneous tissue, and further investigated the role of stem cells in wound healing and their association with skin disease. In this study, we investigated the localization of CD271+ cells in human skin (epidermis and dermis) and its age-related changes in stem cells using CD271+ cells. The study revealed that the number of CD271+ cells in the epidermis and dermis decreased with aging. It is possible that such an age-related decrease in stem cells causes impaired regenerative ability and is associated with various skin diseases. If the relationship between stem cells and skin aging and diseases can be elucidated by investigations such as this study, it may lead to the development of novel anti-aging technologies and medical treatments for skin diseases in the future. [ABSTRACT FROM AUTHOR]

Malassezia folliculitis [MF] is caused by the invasion of hair follicles by large numbers of Malassezia cells, but it remains unclear which Malassezia species are involved in the disease. To clarify this situation, Malassezia species isolated from lesions of MF patients were analyzed by both culture and non-culture methods. In addition, Malassezia species recovered from the non-lesion areas of the skin of MF patients and skin samples of healthy subjects were included in this study. The test population consisted of 32 MF patients and 40 healthy individuals. The lesions were obtained using a comedone extractor, while swabs were employed to obtain skin samples from non-lesion areas of the patients and healthy subjects. Malassezia DNA was analyzed using a real-time PCR technique. The detection limit of the culture method was 5 CFU/cm2 as opposes 50 cells/cm2 with non-culture procedures. The predominant species recovered from MF lesions were M. globosa and M. sympodialis by culture method analysis, and M. restricta, M. globosa, and M. sympodialis with non-culture methods. These results were in agreement with those found with samples from non-lesion skin areas of MF patients and healthy subjects. This study clarified that MF is caused by Malassezia species that are part of the cutaneous microflora and not by exogenous species. [ABSTRACT FROM AUTHOR]

Abstract: The inhibition effects of nitrogen compounds on CoMoP/Al2O3 catalysts due to doping with Li or USY-zeolite in the hydrodesulfurization (HDS) of dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) have been studied. Quinoline was selected as the model nitrogen compound. Changes in the HDS rate, conversion and selectivity were investigated. The acidity of the oxidic catalysts was studied using Fourier-transformed infrared spectroscopy (FT-IR), pyridine adsorption, and ammonia temperature-programmed desorption (NH3-TPD). The catalysts were studied in both oxidic state and sulfidic state by X-ray photoelectron spectroscopy (XPS). The HDS of DBT as a reference probe molecule is thought to proceed first through direct desulfurization pathways, then to hydrogenolysis. A significant amount of benzene was detected in the case of CoMoP/zeolite-Al2O3. The HDS of 4,6-DMDBT over CoMoP/zeolite-Al2O3 in the absence of quinoline proceeds through a very complex mechanism that involves several other reactions, such as isomerization, alkylation, and hydrocracking. This can probably be attributed to the acidic properties of zeolite. In the presence of quinoline, a strong inhibition effect was observed for all the catalysts. The inhibition effects of quinoline on CoMoP/Al2O3-Li were smaller than its effects on the other catalysts; this fact resulted in the enhancement of HDS activity. Moreover, from the XPS investigations we can conclude that CoMoP/Al2O3-Li showed a relatively higher sulfidation degree for both Mo and Co. Thus, it seems to have a relatively higher catalytic activity. [Copyright &y& Elsevier]

Describes the design consideration and performance of a K alpha-band monolithic phase shifter using nonresonant field effect transistor switches. Indication of a broad-band on/off characteristics up to 60 gigahertz; Possibility of a robust circuit design for a switched-line phase shifter; Introduction of a schematic design approach.