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Biomedical subjects

S Arase

Publications and source records attributed to S Arase.

At least 55 records · Page 3Linked to original sources
PubMed1995

A rudimentary system for automatic discrimination among basic skin lesions on the basis of color analysis of video images.

BACKGROUND: Detection of differences in color is necessary for an automatic diagnostic system for skin lesions. OBJECTIVE: The purpose of this study was to examine whether color analysis of an image obtained with a videomicroscope can be used as a key to distinguish basic skin lesions. METHODS: We carried out quantitative color analyses of nine kinds of natural or artificial skin lesions. After images of the lesion and adjacent normal skin were obtained, the difference in the mean quasiabsorbance (logarithm of the inverse reflectance) values between the two were examined in each color band of red, green, and blue by an image analytic method. RESULTS: We could determine a set of thresholds of quasiabsorbance values to distinguish between basic lesion colors. On the basis of these results we developed a rudimentary system that automatically offers possible diagnoses of a test site. CONCLUSION: The algorithm that we developed may be of value in an initial screening of skin lesions in an automatic diagnosis system.

Absorption↗
PubMed1995

Malignant melanoma developing in an area of palmoplantar keratoderma (Greither's disease).

We report a case of malignant melanoma arising on the hyperkeratotic sole of a patient with palmoplantar keratoderma (PPK). Hyperkeratotic lesions were also seen on the dorsa of both hands and feet and the extensor aspects of elbows and knees. The patient's PPK appeared to have been transmitted by an autosomal dominant gene. Histologically, the hyperkeratotic lesions showed acanthosis, marked hyperkeratosis without parakeratosis, and hypergranulosis. All the findings corresponded to those of Greither's disease with malignant melanoma.

Adult↗
PubMed1995

Striated muscle hamartoma of the nostril.

We observed two females, an 11-month old and a 15-year-old, each with a round, soft mass in the nostril. Histologically, numerous bundles of striated muscle fibers were seen in the masses among normal dermal components. The lesions were excised without complications. Four patients with similar lesions confirmed clinically and histologically have been reported in the literature under various diagnostic names. These masses were diagnosed as striated muscle hamartomas in view of their characteristic features: congenital round, soft masses on the midline of the head or neck with multiple, mature striated muscles observed in the mass. Since these lesions may be associated with such anomalies as amniotic band syndrome and lipoma of the brain, a complete medical examination is required of such patients.

Adolescent↗
PubMed1995

Serial cultivation of human nail matrix cells under serum-free conditions.

We have established serial cultures of human nail matrix cells (NMCs) under serum-free conditions. We cultured NMCs using two different methods depending upon the volume of nail matrix obtained. When a sufficient amount of nail matrix was obtained, they were minced and treated with 0.25% trypsin and 0.03% EDTA. The NMCs were transferred directly as a dispersed cell culture into KGM medium. Because a sufficient amount of matrix was rarely obtained, we developed a method by which NMCs were cultured primarily as implanted small matrices in Eagle's MEM (high Ca+ medium) supplemented with 15% fetal bovine serum for the first 4 to 5 days; during this time, the NMCs expanded from the matrices and formed colonies around them. NMCs then were cultured with KGM. In both methods, KGM medium supported the growth of NMCs without a biological feeder layer. These cells could be cultivated serially for at least seven passages. Half of the cells were positively stained with a monoclonal antibody against hair (hard) keratin which is expressed in nail matrix in vivo, indicating that the cells originated from the nail matrix. These methods will now permit investigations of nail matrix cells that previously were unfeasible because of the relative lack of cells and difficulties with propagation.

Animals↗
PubMed1994

Effect of minoxidil sulfate and pinacidil on single potassium channel current in cultured human outer root sheath cells and dermal papilla cells.

Minoxidil sulfate and pinacidil are K channel openers and are considered to promote hair growth. However, there have been no studies on the single channel current of isolated cells from hair follicles. Therefore, we characterized the single K channel current of outer root sheath cells and dermal papilla cells and the effect of K channel openers on K currents by patch clamp. We also carried out 86Rb efflux studies to observe macroscopic K channel currents. In physiological saline, these two cells showed two types of K channels, large and small conductance Ca(2+)-activated K channels, both intact cell-attached and excised inside-out patches. In symmetrical 150 mM K solution, unitary conductances were 246 and 70 pS, respectively. Intracellular ATP (up to 5 mM) or glibenclamide (20 nM), a specific ATP-sensitive K channel blocker, did not block these channels. Minoxidil sulfate (5 micrograms/ml) or pinacidil (10 microM) did not open these two types of K channels or increase 86Rb efflux. These results suggest that minoxidil sulfate or pinacidil did not activate K channel current in hair follicles, and that the drug effect on hair growth might be mediated by other mechanisms such as increased blood flow.

Calcium↗
PubMed1994

p53 gene mutations in human skin cancers and precancerous lesions: comparison with immunohistochemical analysis.

Mutations of exons 3 through 9 of the p53 gene in skin lesions were screened in 23 cases of squamous cell carcinoma (SCC), 25 cases of basal cell carcinoma (BCC), two cases of Bowen's disease, 10 cases of solar keratosis, and five cases of keratoacanthoma by polymerase chain reaction--single strand conformation polymorphism analysis. Mutations of the p53 gene were detected in seven of 23 SCCs (30%), three of 25 BCCs (12%), and none in all cases of Bowen's disease, solar keratosis, or keratoacanthoma. Of 23 cases of SCC, mutations were detected in four of 15 SCCs (27%) that originated in the sunlight-exposed skin region, in two of three SCCs (67%) that originated in the scar tissue, and in one of three SCCs (33%) that originated in radiation dermatitis. Mutations of C-->T transition predominated in SCC and BCC that originated in the sunlight-exposed skin region. Mutations of C-->A or CC-->AT observed in tumors that originated in the predisposed conditions, presumably unrelated to UV light, are different from those found in UV light-related SCC or BCC. Twelve cases of SCC were comparatively analyzed with the immunohistochemical staining with anti-p53 antibody. Two of four cases with positive staining had missense mutations, and three of eight cases with negative staining had nonsense mutations. Based on these findings, immunohistochemical results do not necessarily mean the presence or absence of p53 gene mutations in skin tumors, and sequence analysis is essential for determining whether the gene is mutated.

Aged↗
PubMed1994

The degrees of UVB-induced erythema and pigmentation correlate linearly and are reduced in a parallel manner by topical anti-inflammatory agents.

To examine whether it is possible to evaluate the degree of ultraviolet B (UVB)-induced inflammation by measuring the degree of hyperpigmentation, we investigated the relationship between UVB-induced erythema and the subsequent pigmentation quantitatively. At 24 h and 7 d after irradiation with erythemogenic doses of UVB to the backs of 16 Japanese subjects, the degree of induced erythema (delta erythema index) and that of pigmentation (delta melanin index) were examined by an image analytic method using a videomicroscope interfaced with a computer. The relationship between two indices was linear in each subject, and the correlation coefficient was 0.83 when evaluated using whole data. The slope of the regression line for the delta melanin index against delta erythema index tended to become steeper as non-irradiated skin color became darker (r = 0.63), suggesting that more efficient melanogenesis takes place after the same level of inflammation in the subject with darker skin. Both erythema and hyperpigmentation were suppressed significantly and in a parallel manner by corticosteroids and indomethacin applied topically immediately after UVB irradiation. These results imply that the post-inflammatory hyperpigmentation correlates closely with the severity of the prior inflammation and that chemical mediators released in the inflammatory process have considerable influence on the melanogenesis. We conclude that the measurement of UVB-induced hyperpigmentation can be utilized for the assessment of topical anti-inflammatory agents, unless these have direct actions on the tyrosinase activity of melanocytes.

Administration, Topical↗
PubMed1994

Quantification of erythema and pigmentation using a videomicroscope and a computer.

We report a method for quantitative analysis of erythema and pigmentation using a videomicroscope interfaced with a computer. The analysis was carried out by examining the brightness intensity of every picture element, composed of an image picked up from each band of red, green, and blue, and by deriving the quasi-absorbance value (absorbance index) from the mean brightness for each band. In assessments of UV-induced erythema and tanning, excellent linear correlations were found between the results obtained with our system and those with a narrow-band reflectance spectrometer. Moreover, the absorbance indices of haemoglobin and melanin solutions showed linear relationships with their concentrations in in vitro examination. As the monitored picture becomes out of focus if incorrect pressure is exerted on the skin, and as regions of interest can be chosen from a magnified image, this system offers excellent interobserver reproducibility, and is suitable for the evaluation of erythema or pigmented lesions which are too small or irregular to quantify by conventional methods such as colorimetry.

Adrenal Cortex Hormones↗
PubMed1994

Experimental approaches for the reconstitution of hair in vitro.

When plucked follicles were cultured together with isolated dermal papillae in a collagen gel matrix, outer root sheath cells (ORSCs) grew more rapidly and actively than without the papillae. Cultured dermal papilla cells also activated the colony growth of ORSCs in vitro. These results may suggest the existence of some papilla-derived factor(s) activating the growth of ORSCs. In cultures of excised whole follicles whose dermal papilla had been removed, epithelial cells of bulb matrix origin grew out from the bulbous portion, and formed spikes. When a dermal papilla was implanted close to the follicle, the spikes elongated toward the papilla, and finally reached and surrounded it. This finding suggests that dermal papillae may produce some factor(s) attracting epithelial cells of hair bulb origin. In cultures of excised whole follicles, when the dermal papilla remained originally positioned in contact with the hair bulb matrix, the hair and follicle elongated for more than 1 week. But when the dermal papilla was detached from the bulb matrix, the matrix cells proliferated into the gel and formed a hair-follicle-like structure (folliculoid). In cultures of excised whole follicles whose papilla-matrix junction had been damaged by dispase, elongation of the hair and follicle was almost completely suppressed. Thus, the attachment of the dermal papilla to the bulb matrix appears to be necessary for normal hair and follicle growth.

Cell Division↗
PubMed1993

Arachidonate 12-lipoxygenase of platelet-type in human epidermal cells.

A homogenate of epidermal cells isolated from human skin converted arachidonic acid to 12S-hydroxy-5, 8,10,14-eicosatetraenoic acid and 15-hydroxy-5, 8,11,13-eicosatetraenoic acid as the main lipoxygenase products. The production of these hydroxy acids was not stimulated by the addition of 1 mM NADPH required for cytochrome P-450 reaction, but inhibited by 65-75% with 40 microM nordihydroguaiaretic acid, a nonspecific lipoxygenase inhibitor. In addition to these lipoxygenase products, the epidermal cell homogenate converted arachidonic acid to prostaglandin E2 together with minor amounts of prostaglandins D2 and F2a and 12-hydroxy-5,8,10-heptadecatrienoic acid. Thromboxane B2 was not detected. This finding rules out the possible contamination of platelet 12-lipoxygenase in the epidermal cells. After subcellular fractionation of the epidermal cell homogenate, the 12-lipoxygenase activity was found in the 164,000 x g supernatant, the 164,000 x g pellet, and the 10,000 x g pellet. The cytosolic enzyme and the enzymes solubilized from the two pellets produced 12S-hydroperoxy-5,8,10,14-eicosatetraenoic acid as the primary product in contrast to cytochrome P-450 which produces primarily hydroxy acids. The 12-lipoxygenase in the 164,000 x g supernatant and the solubilized enzymes from the 164,000 x g pellet and 10,000 x g pellet were precipitable by antibodies raised against human platelet 12-lipoxygenase, but not by antibodies against porcine leukocyte 12-lipoxygenase. The immunoprecipitated 12-lipoxygenase from each fraction was almost inactive with linoleic acid as substrate, characteristic of 12-lipoxygenase of platelet-type. Furthermore, 12-lipoxygenase mRNA in the epidermal cells could be reverse-transcribed and amplified by polymerase chain reaction with the primers specific for human platelet 12-lipoxygenase cDNA, but not with those for porcine leukocyte 12-lipoxygenase cDNA. Thus, the 12-lipoxygenase of human epidermal cells is similar to human platelet 12-lipoxygenase in terms of immunogenicity, catalytic property, and primary structure, and distinct from leukocyte 12-lipoxygenase.

12-Hydroxy-5,8,10,14-eicosatetraenoic Acid↗
PubMed1993

Dispersed cell culture of human sweat duct cells under serum-free conditions.

Human eccrine gland duct cells were successfully cultured using a serum-free medium, K-GM medium. Eccrine sweat ducts were isolated from dispase treated skin specimens from palms or soles. After treatment of the isolated ducts with trypsin and EDTA, dispersed cells were cultured in K-GM medium. In primary cultures, small colonies were seen 3 to 4 days after inoculation. Then the cells rapidly proliferated and formed large colonies with a paving stone-like cell arrangement. During the culture, small dome shaped areas were sometimes formed in the centers of colonies. Cultures multiplied for a maximum of 7 passages. The plating efficiencies of the 1st to 6th passage cells were about 20% to 30%. Immunocytochemically, cultured cells were positively stained with anti-carcinoembryonic antigens, K8.37 and K8.13, but not with anti-S100 protein, anti-HLA-DR, 34 beta B4, or PKK3. An electron micrograph of the cultured cells showed a multilayer of flattened cells linked by desmosomes. These results indicate that the cultured cells possessed the staining properties compatible with those of the ductal portion of eccrine sweat glands. No contamination by other mesenchymal cells, such as fibroblasts, was seen during the culture.

Antigens↗
PubMed1993

Light microscopic autoradiographical analysis of [125I]epidermal growth factor binding in basal cell epithelioma and squamous cell carcinoma of the skin.

Levels of epidermal growth factor (EGF) receptor expression were investigated in five basal cell epitheliomas (BCEs) and 10 primary lesions from squamous cell carcinoma (SCC) of the skin, using light microscopic autoradiography with [125I]EGF. All of the BCEs were clinically the pigmented type and histologically the solid type. All of them showed an EGF binding level similar to that of the basal and suprabasal layers of the normal epidermis. The SCCs included one case of Bowen's disease (SCC in situ), five of the well differentiated type, three of the moderately differentiated type and one of the poorly differentiated type. Eight of the 10 SCCs showed an EGF binding level similar to that of the normal epidermal basal and suprabasal cell layers. One of the two remaining SCCs, a moderately differentiated type, showed highly increased EGF binding. The other one, a poorly differentiated type, showed very little EGF binding in a large region consisting of poorly differentiated cells, although a small area composed of more differentiated, nest-forming cells had an EGF binding level similar to that of the basal and suprabasal cells. Metastasis was found in three of these 10 SCCs after surgery. Two of the three SCCs with metastasis showed increased or decreased EGF binding levels in primary lesions as described above; in contrast, primary lesions of the seven SCCs without metastasis had EGF binding levels similar to those of the normal epidermal basal and suprabasal cells. Abnormally increased or decreased EGF binding level in SCC of the skin may be indicative of a poor prognosis, although it is necessary to examine more SCCs to confirm this assumption.

Aged↗
PubMed1992

Immunohistological analysis of P53 expression in human skin tumors.

The p53 expression in various skin tumors was immunohistologically evaluated using two mouse monoclonal anti-p53 antibodies, PAb421 and PAb1801. The p53 expression was not detected in the normal epidermal cells. Nuclear staining suggested that the p53 expression was observed in 10 of 26 squamous cell carcinomas (SCCs) from 24 patients, in one undifferentiated carcinoma, one proliferating trichilemmal cyst, one malignant proliferating trichilemmal tumor and in one metastatic carcinoma of breast cancer. None off four cases of Bowen's disease (SCC in situ) showed nuclear staining. In the SCCs, five of 20 primary lesions, three of four recurrent lesions and both of two metastatic lesions had positive nuclei. There was one case of SCC in which a primary lesion was negative but a recurrent lesion was positive. Thus, p53 expression was more frequently observed in SCCs at more clinically advanced stages. This may suggest that p53 has some relevance to progression of SCC. Nuclear staining was not detected in any of the following cases: two cases of seborrheic keratosis, one eccrine poroma, one keratoacanthoma, 11 basal cell epitheliomas, two mammary Paget's disease, three genital Paget's disease, one sebaceous carcinoma, four malignant melanomas, six lymphomas, two leukemia cutis and two angiosarcomas.

Antibodies, Monoclonal↗
PubMed1991

The effect of 1,25-dihydroxyvitamin D3 on the growth and differentiation of cultured human outer root sheath cells from normal subjects and patients with vitamin D-dependent rickets type II with alopecia.

We examined the effect of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) on the growth and differentiation of cultured human hair outer root sheath cells (ORSC) from normal subjects and patients with vitamin D-dependent rickets type II (DDR-II) with alopecia. 1,25(OH)2D3 dose-dependently suppressed the plating efficiency, clonal growth, and DNA synthesis of normal ORSC. It enhanced the cornified envelope formation and caused morphological changes in the cells. All results indicated the existence of specific receptors for 1,25(OH)2D3 in the ORSC, and suggest that 1,25(OH)2D3 is a potent inhibitor of proliferation of ORSC as well as a stimulator of terminal differentiation. However, the cells from DDR-II patients with alopecia did not respond to 1,25(OH)2D3, suggesting a lack of the specific receptors in the cells. The differences in the cellular response to the hormone between the normal ORSC and those from the patients were apparent and easily distinguishable, therefore this experiment may be a rapid and simple diagnostic test for DDR-II patients with alopecia. Large number of hairs were difficult to obtain from patients with alopecia, and we developed a new culture method to accomplish these studies from a few plucked hair follicles. Our system may be useful in the culture of ORSC from limited number of follicles, and could be utilized to analyse the cellular characteristics of ORSC in patients with hair diseases.

Alopecia↗
PubMed1991

Culture of human outer root sheath cells from plucked hair follicles in serum-free conditions.

We succeeded in culturing human outer root sheath cells (ORSC) in serum-free conditions without a biological feeder layer. The combination of collagen type IV substrate and modified MCDB 153 medium supplemented with bovine pituitary gland extract (K-GM medium) could support the growth of ORSC. These cells can be serially cultivated for at least 4 passages and stored in liquid nitrogen with good recovery. Thus, a large series of experiments using ORSC may be run simultaneously.

Cell Division↗