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Y Urano

Publications and source records attributed to Y Urano.

At least 55 records · Page 3Linked to original sources
PubMed1997

Mutations of the INK4a locus in squamous cell carcinomas of human skin.

The INK4a locus encodes two different, cell cycle-regulating proteins, p16INK4a and p19ARF. In this study, we screened mutations in all coding regions of the INK4a locus (exons 1 beta, 1 alpha, 2, and 3) in 21 squamous cell carcinomas (SCCs) of human skin by polymerase chain reaction-single strand conformation polymorphism analysis. Mutations were detected in 3 SCCs in exon 2, which is common to both p16INK4a and p19ARF. These included an in-frame deletion of 21 base pairs from codon 84 to 90, a frameshift mutation of CCC-->TC at codon 75, and a nonsense mutation of CGA-->TGA at codon 80 of the p16INK4a gene. These results suggest that inactivation of the INK4a locus has some relevance to the carcinogenesis in at least some of SCCs of human skin. This is the first demonstration of aberrations in the INK4a locus in SCCs of human skin.

Carcinoma, Squamous Cell↗
PubMed1997

p53 gene mutation analysis in porokeratosis and porokeratosis-associated squamous cell carcinoma.

In this and previous studies, we have shown p53 overexpression immunohistochemically in 14 of 17 porokeratotic specimens obtained from 14 lesions of nine cases, and in all six specimens of squamous cell carcinoma (SCC) arising on porokeratotic lesions of two cases. We screened mutations in exons 5 to 10 of the p53 gene in all these specimens by polymerase chain reaction-single strand conformation polymorphism analysis. Mutations of the p53 gene were detected in two of the six SCCs but not in any of the 17 porokeratotic specimens. These two mutations were C to T transitions at codons 146 and 175 in exon 5, which were a nonsense mutation at a dipyrimidine site and a missense mutation at a CG site, respectively. To our knowledge, neither of these mutations has been identified in skin cancers before. Our observations indicate that mutations of the p53 gene are not the major molecular etiology for porokeratosis, but are related to its skin carcinogenesis, and that p53 overexpression in porokeratosis is not due to p53 gene mutations.

Adult↗
PubMed1997

A case of dermatomyositis complicated by thrombotic thrombocytopenic purpura.

A 60-year-old man with dermatomyositis was admitted to our hospital because of dyspnea and hypertension. He had high fever and convulsive seizures after admission. Laboratory examinations showed hemolytic anemia, thrombocytopenia, and renal failure. A clinical diagnosis of thrombotic thrombocytopenic purpura (TTP) was made. He failed to respond to plasma exchange therapy, pulse therapy with methylprednisolone, high-dose gamma-globulin therapy, and antiplatelet therapies with ticlopidine, dipyridamole and a prostacyclin analog of beraprost sodium. He died on his 17th day in hospital. Autopsy examination revealed widespread microthrombi in his kidneys, lungs, spleen, and intestine. Only seven cases of dermatomyositis or polymyositis complicated by TTP have been cited in the literature. TTP was fatal in 6 of these 7 cases. Early diagnosis and prompt treatment may improve the outcome of TTP patients with dermatomyositis. Dermatologists should keep in mind that TTP occasionally arises as a serious complication of dermatomyositis.

Anti-Inflammatory Agents↗
PubMed1997

Cytotoxicity of some oxysterols on human vascular smooth muscle cells was mediated by apoptosis.

A decrease in smooth muscle cells is observed in advanced atherosclerotic lesion. To understand this mechanism, we selected oxysterols as candidates for toxic lipid, and examined their cytotoxicity on human cultured vascular smooth muscle cells, together with the manner of cell death. In the presence of 7-ketocholesterol or 7 beta-hydroxycholesterol (50 mumol/L), the percentage of detached cells increased significantly with dose dependency, and an increase in detached cell number and DNA nick detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling study (TUNEL) preceded an increase in lactate dehydrogenase released into the medium. DNA extracted from smooth muscle cells incubated with 7-ketocholesterol or 7 beta-hydroxycholesterol showed a laddering pattern on agarose electrophoresis. In the presence of 7-ketocholesterol or 7 beta-hydroxycholesterol, fragmented DNA quantified by the quantitative sandwich enzyme immunoassay was significantly increased. From these results, it is proposed that 7-ketocholesterol and 7 beta-hydroxycholesterol are toxic to smooth muscle cells, and that this cytotoxicity is mediated by apoptosis.

Apoptosis↗
PubMed1997

A case of episodic angioedema associated with eosinophilia.

BACKGROUND: Gleich et al. first described 4 cases of episodic angioedema associated with eosinophilia as a distinct entity in 1984. Since then, several cases of this disorder have been reported in the United States, Europe and Japan. OBSERVATIONS: We report a case of a 22-year-old pregnant Japanese woman with this disorder. She had no fever and her general condition was good except the angioedema which was limited to her limbs. During an acute episode, her white blood cell count increased to 29,500/mm3 with 50% eosinophils, following an elevated serum interleukin-5 (IL-5) level. Spontaneous resolution occurred in 1 month after the onset. In a 5 month follow-up, no evidence of cardiac or other visceral organ involvement was found, and no recurrence occurred. CONCLUSIONS: Our case, combined with those reported in the literature, suggests that Japanese cases of episodic angioedema associated with eosinophilia differ from Caucasian cases in clinical symptoms and some other points.

Adult↗
PubMed1996

Culture of cells derived from the human sebaceous gland under serum-free conditions without a biological feeder layer or specific matrices.

We succeeded in serially culturing cells derived from human sebaceous gland (sebocytes) under serum-free conditions. Sebaceous glands were isolated from dispase-treated facial skin specimens and cultured using two different methods, explant culture and dispersed cell culture, in KGM. In both types of culture the sebocytes proliferated rapidly without a biological feeder layer or specific matrices. It was possible to cultivate the cells serially for at least three passages (explant culture) and six passages (dispersed cell culture), and to store the cells in liquid nitrogen with good recovery. Analytical thin-layer chromatography revealed that the cells synthesized a large amount of sebum-specific lipids, squalene and wax esters in vitro. Both testosterone and 5 alpha-dihydrotestosterone significantly stimulated the proliferation of the sebocytes. The methods presented here may permit a large series of studies on the function of sebaceous glands or cells derived from sebaceous glands.

Cell Culture Techniques↗
PubMed1996

Immunohistochemical detection of p53 tumor suppressor protein in porokeratosis.

We examined 9 Japanese cases of porokeratosis (4 of the plaque type, 2 of disseminated superficial actinic porokeratosis, 2 of disseminated superficial porokeratosis, and one of giant porokeratosis) for the expression of p53 tumor suppressor protein immunohistochemically, using two anti-p53 antibodies, CM1 and DO1. The same results were obtained with both antibodies. The epidermis central to the cornoid lamellae was positive in 8 of 9 specimens. On the other hand, the peripheral epidermis was positive in 2 of the 9 cases. The epidermis beneath the cornoid lamellae was positive in 3 of the 9 cases. The frequency of p53 positivity was significantly higher in the epidermis central to cornoid lamellae over that beneath or peripheral to them (Fisher's exact probability test, p < 0.05). The majority of squamous cell carcinoma cells arising on giant porokeratosis stained with CM1 and DO1. These data may suggest that the abnormal p53 expression has some relevance to the skin carcinogenesis of porokeratosis.

Adult↗
PubMed1996

[Bucillamin induced lung injury in rheumatoid arthritis].

Thirteen cases with rheumatoid arthritis who experienced lung injury during the treatment with bucillamine (Bc), about whom the questionnaires were answered by the physicians and whose X-ray films could be rechecked, were studied. Nine cases out of the 13 showed patchy mottled infiltrates in the bilateral center sparing the periphery, and the other 4 showed diffuse infiltrates. In these 9, serum gamma-globulin level decreased when lung injury appeared. The gamma-globulin level before the start of Bc administration, the level when lung injury appeared, the gamma-globulin decrease, and its ratio to the level before Bc were 1790 +/- 661 mg/dl, 1297 +/- 666 mg/dl, 459 +/- 320 mg/dl and 29.1 +/- 18.0%, respectively. In 5 out of the 9, gamma-globulin level reincreased when they recovered from the injury: 2 out of the 5 showed the reincrease even after steroid therapy. The data were obtained only from 2 out of the 4 with diffuse pattern in X-ray, and the decrease and the decrease ratio were 200 mg/dl (5.8%) in 1, and 49 mg/dl (3.6%) in the other. The characteristics of Bc-induced lung injury might be mottled infiltrates in the center appearing concurrently with serum immunoglobulin decrease.

Aged↗
PubMed1995

Frequent p53 accumulation in the chronically sun-exposed epidermis and clonal expansion of p53 mutant cells in the epidermis adjacent to basal cell carcinoma.

p53 expression was studied immunohistochemically to identify a precursor lesion of basal cell carcinoma (BCC) in the epidermis adjacent to BCC. With two different anti-p53 antibodies of CM1 and DO7, p53 expression was frequently detected in the epidermis adjacent to BCCs arising on the face and in the normal epidermis with usual sun exposure. In the epidermis adjacent to BCC, stained cells were occasionally clustered in a small area, but no cluster was found in the normal epidermis with usual sun exposure. The expression was less frequent in the normal epidermis with rare sun exposure. Ten cases of normal skin with usual sun exposure, showing CM1 staining in the epidermis, were screened for p53 gene mutations with polymerase chain reaction-single-strand conformation polymorphism analysis using DNAs obtained from the epidermis. No mutation was detected in exons 2 to 10 of the p53 gene in these 10 cases. The epidermis flanking three BCCs that was stained with CM1, on the other hand, carried a missense mutation of C to G transversion at a dipyrimidine site of codon 249. This alteration replaced arginine with threonine. The mutation of codon 249 was not detected in the three BCCs. Our results first suggest that ultraviolet light irradiating the skin in a daily life induces p53 accumulation in the epidermis and secondly that the frequent clonal expansion of p53 mutant cells occurs in the epidermis adjacent to BCCs. This clonal expansion of mutant p53 may provide a molecular basis for high risk of developing subsequent new skin cancers in patients with BCC.

Adolescent↗
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

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

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↗