We prepared a supramolecular hydrogel composed of decanoic acid and arginine (C10/Arg gel) and evaluated its application to a transdermal formulation. C10/Arg gel adjusted to pH 7 with 1 M NaOH aq or 1 M HCl aq provided a translucent hydrogel with a lamellar liquid crystal structure in the concentration region of decanoic acid ≥12% and arginine ≤9%. Rheological measurements showed that C10/Arg gel is a viscoelastic material with both solid and liquid properties, with elasticity being dominant over viscosity in the low shear stress region.
View Article and Find Full Text PDFPatch tests are often used in safety evaluations to identify the substance causing skin irritation, but the same substance can sometimes give positive or negative results depending on the test conditions. Here, we investigated differences in the skin penetration of two test compounds under different application conditions. We studied the effects of the anionic surfactant sodium dodecyl sulfate (SDS) and the nonionic surfactant polysorbate 80 (PS) on skin penetration of the preservatives methylisothiazolinone (MT) and methylchloroisothiazolinone (MCT), which are used in cosmetics such as shampoos.
View Article and Find Full Text PDFGiant cell arteritis (GCA) is a chronic vasculitis that primarily affects the elderly, and can cause visual impairment, requiring prompt diagnosis and treatment. The global impact of the coronavirus disease 2019 (COVID-19) pandemic has been substantial. Although vaccination programs have been a key defense strategy, concerns have arisen regarding post-vaccination immune-mediated disorders and related risks.
View Article and Find Full Text PDFWe investigated the effect of the rheological properties and composition of lecithin reverse wormlike micelles (LRWs) on the skin permeation of a model of a hydrophilic drug to determine whether LRWs support uniform hydrophilic drug/oil-based formulations and good drug penetrate into skin. Here, we prepared LRWs with D (-)-ribose (RI) or glycerol (GL) as polar compounds, liquid paraffin (LP) or isopropyl myristate (IPM) as oils, and 6-carboxyfluorescein (CF) as a model for a hydrophilic drug, and evaluated the rheological properties and skin penetration characteristics of the preparations. The LRWs showed moderate viscosity at 25 °C, a typical storage temperature, but decreasing viscosity at 32 °C, the surface temperature of human skin, suggesting that the LRWs would penetrate the microstructure of skin (e.
View Article and Find Full Text PDFSignificance: Skin capillaries are non-invasively observable; their structure and blood flow can reflect tissue and systemic conditions. Quantitative analysis of video-capillaroscopy images yields novel diagnostic methods. Because the capillary structure is heterogeneous, analyzing more capillaries can increase the evaluation reliability.
View Article and Find Full Text PDFAnalysis of pollution of the ocean plastics is presently being extensively carried out but special attention should be direct to matters. It is widely believed that plastic dose not decompose in the ocean. Certain contaminants, bisphenol-A (BPA) that serves the material for polycarbonate (PC) and epoxy resin (EPX) both of which may possibly be elute or degrade from commercial products, have often been detected in rivers, lakes and oceans.
View Article and Find Full Text PDFThe aim of this study is to validate an in vitro skin irritation test (SIT) using three-dimensional reconstructed human epidermal (RhE) skin equivalents prepared by layer-by-layer (LbL) method (LbL-3D Skin) in a series of interlaboratory studies. The goal of these validation studies is to evaluate the ability of this in vitro test to reliably discriminate skin irritant from nonirritant chemicals, as defined by OECD and UN GHS. This me-too validation study is to assess the within- and between-laboratory reproducibility, as well as the predictive capacity, of the LbL-3D Skin SIT in accordance with performance standards for OECD TG 439.
View Article and Find Full Text PDFAtopic dermatitis (AD) is a chronic inflammatory skin disease. Prevention of exacerbation of AD is a crucial issue for all physicians. However, exacerbation of AD often is seen during reduction of AD treatment, even with appropriate follow-up by tapered topical corticosteroids and daily topical moisturizers, indicating the need for good indicators of AD remission.
View Article and Find Full Text PDFLecithin reverse wormlike micelles (LRWs) have been studied recently for dermal application dosage use but the effects of the physicochemical properties of oils on the formation and rheological properties of LRWs have not been investigated. We studied the effect of oil on the formation of LRWs using 5 types of liquid paraffin (LP) with kinematic viscosities ranging from 4.00 to 88.
View Article and Find Full Text PDFChem Pharm Bull (Tokyo)
December 2021
Our aim was to determine the surface free energy (SFE) of semi-solid dosage forms (SSDFs) by establishing a reproducible method for measuring the contact angle of liquids to SSDFs. Four SSDFs were used: petrolatum, an oil/water (O/W) and a water/oil (W/O) cream, and an alcohol-based gel. The SSDFs were evenly spread on a glass slide, and the change in contact angle over time was measured by dropping water, glycerol, diiodomethane and n-hexadecane as the test liquids.
View Article and Find Full Text PDFFront Genet
September 2021
Neuroendocrine carcinoma (NEC) of the esophagogastric junction (EGJ) is a rare disease with no established treatments. Herein, we describe a case of recurrent squamous cell carcinoma (SCC) after achieving complete response to chemotherapy against NEC of the EGJ. A 67-year-old man was referred to our hospital because of epigastric discomfort.
View Article and Find Full Text PDFHydrophobically modified hydroxypropyl methylcellulose (HM-HPMC), a polymer in which a small amount of HPMC is stearoxyl substituted, was used as an emulsifier of emulsion-type lotion. A high-pressure homogenizer (microfluidizer) was used. The viscosity of the 1% HM-HPMC aqueous gel decreased after passing through the microfluidizer from 5.
View Article and Find Full Text PDFHydrophobically-modified hydroxypropylmethylcellulose (HM-HPMC) is a thickener with a long hydrophobic alkyl side chain. In this study, we investigated the gelation ability and rheological properties of a liposome/HM-HPMC mixed solution. The liposome suspension and the HM-HPMC aqueous solution each had low viscosities, but the viscosity increased rapidly when they were mixed.
View Article and Find Full Text PDFIn this study, we propose a new technique for evaluating wetting and adhesion of lotions to skin using surface tension measurements, contact angle measurements and calculations based on the Owens-Wendt-Rabel-Kaelble (OWRK) method. Three prescription lotions (Napageln Lotion 3%, Sumilu Lotion 3% and Felbinac Lotion 3% 「Rakool」) and two over-the-counter lotions (Feitas Lotion and Salomethyl FB Lotion α) were used. Based on the dispersive and polar components of the surface free energy of Yucatan micro pig (YMP) skin, isograms of contact angle (wetting envelope) and adhesion work of the YMP skin surface were constructed.
View Article and Find Full Text PDFPhotodermatol Photoimmunol Photomed
July 2019
Surface free energy (SFE) is an important factor for evaluation of wettability or adhesion. Thus, the SFE of a Yucatan micropig (YMP) skin and a hairless mouse (HM) skin, which are commonly used in skin permeation studies instead of human skin, were compared with the human skin. Contact angles of water and 1-bromo naphthalene to skin were measured and the SFE was calculated using the Owens-Wendt equation.
View Article and Find Full Text PDFThe emulsion prepared with β-cyclodextrin as an emulsifier (βCDE) is considered to be a Pickering emulsion. We examined the characteristics of βCDEs using captopril (CP) as a model drug, and studied the in vitro skin permeation of CP from βCDEs through hairless mouse skin. The stability of βCDE was increased with increasing βCD concentration and conversely decreased with increasing CP concentration.
View Article and Find Full Text PDFRegulation of gene expression requires selective incorporation of histone H3 variant H3.3 into chromatin. Histone H3.
View Article and Find Full Text PDFNon-allelic histone variants are considered as epigenetic factors that regulate genomic DNA functions in eukaryotic chromosomes. In this study, we identified three new human histone H3 variants (named H3.6, H3.
View Article and Find Full Text PDFHistone H3.Y is conserved among primates. We previously reported that exogenously produced H3.
View Article and Find Full Text PDFH2A.Z is incorporated into nucleosomes located around transcription start sites and functions as an epigenetic regulator for the transcription of certain genes. During transcriptional regulation, the heterotypic H2A.
View Article and Find Full Text PDFWe evaluated testosterone-containing lecithin reverse wormlike micelles (reverse worms) composed of a polar substance/lecithin/isopropyl myristate for transdermal application. Water, D-ribose, or tetraglycerol were used as the polar substance and were key ingredients for forming the reverse worms. Using the reverse worms, 1 wt% of testosterone could be stably solubilized.
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