Publications by authors named "Masahiko Toyoda"

Recently, intensity-modulated radiation therapy (IMRT) is used worldwide, highly accurate verification of the location using image-guided radiation therapy (IGRT) has become critical. However, the use of cone-beam computed tomography (CBCT) to ascertain the location each time raises concerns about its influence on radiotherapy dosage and increased radiation exposure. The purpose of this study was to measure the absorbed dose using nine kilovoltage (kV) devices and two megavoltage (MV) devices (total 11 devices) at eight facilities, compare the absorbed dose among the devices, and assess the characteristics of the respective devices to ensure optimal clinical operation.

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Although the pharmacological profiles and clinical efficacy of antihistamines for patients with atopic dermatitis (AD), one of the representative cutaneous pruritic diseases, have been well documented, the in vivo concentrations of antihistamines in human skin have previously been studied in less detail. In this randomized trial, the suction blister technique was applied to the measurement of the concentrations of epinastine hydrochloride in the extracellular water compartment in comparison with chlorpheniramine maleate in skin from AD patients. A total of 79 patients (mean age, 28.

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Background: Procyanidins are a family of condensed tannins, which have been shown to possess hair-growing activity in both the in vitro and in vivo murine models.

Aims: We report a 12-month clinical study aimed at treating male pattern baldness by external application of 0.7% apple procyanidin oligomers.

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We examined the characteristics of melanin distribution, the possible mechanisms underlying the histological incontinence of pigment, and the significance of epidermal macrophages in photodamaged skin. We used electron microscopy to compare and quantitate melanin distribution in various types of cells and structures, to qualitatively observe associations of melanin granules with melanophages, and to examine morphological differences of epidermal macrophages in sun-exposed versus sun-protected facial skin. Melanin-containing cells (such as Langerhans' cells) and melanin-containing structures (such as colloid bodies) in photodamaged skin were more numerous than in sun-protected skin, in proportion to differences in melanocyte density and in epidermal melanin content.

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Nevus lipomatosus cutaneous superficialis (NLCS) is a rare hamartomatous skin lesion histopathologically characterized by the presence of mature fat tissue even within the upper dermis. Clinically, two types of NLCS can be distinguished; a multiple type and a solitary type. We here report a 10-month-old girl showing multiple type NLCS as a collection of a nodule and papules on her right abdomen.

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Background: It has been reported that the expression of neuropeptides (NPs), and the density and structure of peripheral nerves in atopic dermatitis (AD) are different from those in normal skin.

Objective: We investigated the role of NPs, in the development of AD with quantitative study of substance P (SP) and calcitonin gene-related peptide (CGRP) in the skin of AD-model mice.

Methods: We measured the NPs in the skin of mice (NC/Nga as AD-model mice, BALB/c and C57BL/6 as control) by enzyme-linked immunosorbentassay (ELISA).

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We have recently identified a novel protein named hornerin, the structural features of which are most similar to those of profilaggrin, an essential protein for keratinization of epidermal tissues. In this study we examined the expression of hornerin compared with that of profilaggrin in various mouse tissues. Hornerin was expressed in the upper epidermis of newborn mouse skin, as was profilaggrin.

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There is ample clinical evidence suggesting that the nervous system such as emotional stress can influence the course of acne. We examined possible participation of cutaneous neurogenic factors including neuropeptides, neuropeptide-degrading enzymes and neurotrophic factors, in association with inflammation in the pathogenesis of acne. Immunohistochemical studies revealed that substance P (SP)-immunoreactive nerve fibers were in close apposition to the sebaceous glands, and that neutral endopeptidase (NEP) was expressed in the germinative cells of the sebaceous glands in the skin from acne patients.

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Activin A has been reported to play a role in the progression of colorectal cancer. Because dietary fiber protects against colorectal cancer, we hypothesized that butyrate, a fermentation product of dietary fiber, may affect the expression of activin A in colon cancer cells. Semiquantitative RT-PCR demonstrated that the activin A gene was upregulated by sodium butyrate in the human colon cancer cell lines HT-29 and Caco-2 in a concentration- and time-dependent manner.

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Hair plucking is the most frequently used method of anagen induction within hair follicles. In this study, we found that plucking leads to the entire renewal of the follicular stem cell region of the mouse pelage follicle. Comparative histochemical analysis revealed that S100A4 protein was specifically distributed in the outer layer of the epithelial sac, which has been identified as the stem cell region of the pelage follicle, whereas the slow cycling cells that retained 5-bromo-2'-deoxyuridine label for 8 wk were located in the epithelial sac and also in the hair germ.

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S100A3, a unique protein among all members of the calcium-binding S100 family, is specifically expressed at the inner endocuticle of human hair fibers. Upon hair damage, S100A3 is released from hair fibers and possibly destabilizes the hair tissue architecture. This study describes the purification and characterization of native S100A3 isolated from human hair fibers.

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This review provides a new insight into the participation of neuropeptides, notably substance P (SP), in the pathophysiology of acne. We show morphological alterations of sebaceous glands elicited by SP and differences in expression of various neurogenic factors in association with sebaceous glands in acne-prone versus normal facial skin. In vitro studies reveal that SP promotes both the proliferation and the differentiation of sebaceous glands.

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Senescence-accelerated mice (SAM) were established as a kind of group of related inbred strains that have been used as animal models for accelerated senescence and age-associated disorders. To analyze the characteristics of skin in SAM, the present study examined its morphology at the histological and ultrastructural levels. Histologic comparison of skin from senescence-accelerated-prone (SAM P10) and -resistant (SAM R1) mice revealed that the most characteristic features of SAM P10 were remarkable increases in the number of mast cells and in the density of collagen fibers in the dermis.

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