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S Shimao

Publications and source records attributed to S Shimao.

At least 19 recordsLinked to original sources
PubMed1992

Scanning electron microscopy of the epidermal lamina densa in normal human skin.

The lamina densa of normal human epidermis was exposed by treatment with 1 M sodium chloride and was examined by high-power scanning electron microscopy before and after trypsinization. Localization of type IV collagen in the lamina densa was also studied by transmission and scanning immunoelectron microscopy. Before trypsinization, the surface of the lamina densa consisted of microridges and microvalleys. The microridges varied in height and were connected with each other. They were arranged in a concentric fashion around the tips of the dermal microprojections. At a higher magnification, the surface of the lamina densa was composed of densely packed cobblestone-like structures approximately 7-15 nm in size, between which were interspaces 4-11 nm wide. These structures expressed type IV collagen. After trypsinization, the lamina densa was found to be composed of microfilaments approximately 10 nm thick showing beaded appearances. These microfilaments exhibited the same cobblestone-like structures as the lamina densa surface. Observation of the torn lamina densa demonstrated anchoring fibrils and oxytalan fibers that were attached to the lamina densa itself. Another kind of filament about 7 nm thick linked the anchoring fibrils and the oxytalan fibers. Beneath the lamina densa was a network of fibers about 40-50 nm thick, which was composed of collagen fibers and possibly also elaunin fibers. In conclusion, this study revealed the detailed surface ultrastructure of the epidermal lamina densa and its underlying filamentous elements.

Adult↗
PubMed1992

Angiosarcoma of the thigh with thrombosis in the femoral artery.

We report a case of angiosarcoma with some peculiar clinical features developing on the left thigh of a 63-year-old man. The early primary lesion was erythematous with necrotic areas. The initial biopsy specimen of the lesion indicated a benign angioproliferative process. However, the necrotic area enlarged rapidly, ulcerated with severe pain, and thus was widely excised. The excised specimen had a malignant histologic appearance, particularly in the fascia, and was diagnosed as angiosarcoma. Following local recurrence, the lesion was complicated by thrombosis of the femoral artery at the affected site. A similar cutaneous lesion subsequently arose on the right lower leg, and thrombosis developed in the right femoral artery. Both legs had to be amputated. There were no distant metastases.

Amputation, Surgical↗
PubMed1992

Proteus syndrome: report of the first Japanese case with special reference to differentiation from Klippel-Trenaunay-Weber syndrome.

This is the first report of a Japanese girl with Proteus syndrome. She presented with growth acceleration and precocious development of the left breast as well as macrodactyly, hemihypertrophy, a subcutaneous preaxillary mass, portwine stains, connective tissue nevi, and a depigmented macule. All these abnormalities were confined to the left side of her body. Although most of the manifestations fit those of Proteus syndrome, the presence of the portwine stains and hemihypertrophy also suggested Klippel-Trenaunay-Weber syndrome. The findings in our patient suggest that the most important characteristic distinguishing Proteus syndrome from Klippel-Trenaunay-Weber syndrome is the presence of functional abnormalities such as a growth spurt and precocious breast development. Proteus syndrome may be genetically different from the Klippel-Trenaunay-Weber syndrome.

Child, Preschool↗
PubMed1992

Centrifugal lipodystrophy of the face mimicking progressive lipodystrophy.

We report a Japanese boy with centrifugal lipodystrophy. The initial lesion developed on the forehead as an area of erythema which showed centrifugal spread and central fading to leave a residual depression. Three years later, similar erythematous lesions appeared on the cheeks, and he developed a cadaverous appearance. A central depression on the upper trunk was surrounded by an erythematous border and there was right cervical lymphadenopathy. Histological examination revealed inflammatory changes in the subcutaneous fat. Although this patient showed the characteristics of both centrifugal and progressive lipodystrophy (partial lipodystrophy), we consider that he has centrifugal lipodystrophy of the face because of the overall features of the lesions.

Facial Dermatoses↗
PubMed1992

Acquired tufted angioma showing spontaneous regression.

We report a 62-year-old woman with acquired tufted angioma. Several scattered reddish nodules were present on the neck and upper chest. During a follow-up period of 6 months, some of the lesions showed transient spontaneous regression and one disappeared completely. Electron microscopy revealed that a few tumour cells contained Weibel-Palade bodies in their cytoplasm.

Female↗
PubMed1992

Neuroradiological findings in glutaric aciduria type I: report of four Japanese patients.

We examined neuroradiological computerized tomography (CT) findings and the clinical course of four Japanese children with glutaric aciduria type I (GA1) whose enzyme activity of glutaryl-CoA dehydrogenase was undetectable. Brain CT in all cases examined showed low density white matter, fluid collection in bilateral frontotemporal regions (particularly surrounding the Sylvian fissures), enlargement of the lateral ventricles and slight atrophy of the basal ganglia. Although these findings seemed to be characteristic for GA1, they were unlikely to be more extended, at least over 2 years after infancy. The low density white matter was observed more evidently in the neonatal or early infantile periods than in later periods. The degree of enlargement of fissures in bilateral frontotemporal regions about the Sylvian fissures appeared to correlate with the severity of symptoms such as dystonia or choreoathetosis. Magnetic resonance images (MRI) in one case showed bilateral linear-shaped low intensity in areas of the external capsules and putamen on a T1-weighted image. These CT and MRI findings, as well as clinical symptoms such as choreoathetosis or dystonia, may suggest that metabolic abnormalities in GA1, such as glutaconate, are toxic to the extrapyramidal tract system in the central nervous system, and that the clinical symptoms of the patients are attributable to atrophy of basal ganglia. Brain CT may be useful in diagnosis and evaluation of the clinical course of GA1 patients.

Brain↗
PubMed1992

Cutaneous nerves in cafe au lait spots with white halos in infants with neurofibromatosis. An electron microscopic study.

BACKGROUND AND DESIGN: Although two cardinal skin manifestations of neurofibromatosis are cutaneous neurofibromas and cafe au lait spots, the pathogenesis of cafe au lait spots are very poorly known compared with that of cutaneous neurofibromas. Thus, the cafe au lait spots in two Japanese infants were clinically, histologically, and electron-microscopically investigated. OBSERVATIONS: Some of the cafe au lait spots in the mongolian spots were surrounded by white halos. Histologically, in the cafe au lait spots, the epidermal basal cells had abundant melanin pigment, but macromelanosomes were not seen throughout the epidermis. In the white halo, the epidermal basal cells had a small amount of melanin pigment. Electron microscopically, the cafe au lait spots and their white halos had many subepidermal and intraepidermal nerves that belonged to free nerve endings. All the cutaneous nerves were mature. Some of the intraepidermal nerves had partially or completely naked axons that contacted tightly with the cytomembranes of the basal keratinocytes. Some of the axons in the subepidermal nerves showed degenerative changes only in the white halos. No ultrastructural pathologic changes were observed in the melanocytes, the epidermal keratinocytes, or melanosomes in those cells in the cafe au lait spots and their white halos; also, dermal melanocytes were absent in the both areas. CONCLUSIONS: The increase of the cutaneous nerves and the absence of dermal melanocytes in the cafe au lait spots and their white halos may be considered as characteristic histologic cutaneous findings in infants with neurofibromatosis. However, no evidence indicates that the cutaneous nerves may participate closely in the pathogenesis of the white halos.

Humans↗
PubMed1991

Papillomavirus-infected keratinous cyst on the sole. A histologic, immunohistochemical, and electron microscopic study.

A 17-year-old boy had a keratinous cyst on the sole. The keratinous cyst and its overlying epidermis had solitarily scattered keratinocytes, which contained a peculiar intracytoplasmic inclusion body above the lower spinous layer. Immunohistochemistry and electron microscopy revealed that the nuclei of these cells had virions of papillomavirus. These virions appeared above the spinous layer. The inclusion bodies were highly eosinophilic masses in the viable layer, and slightly basophilic, fine granules in the cornified layer. Their number at any time was usually one. Their histologic and ultrastructural features and their N-(7-dimethylamino-4-methylcoumarinyl)-maleimide staining property were different from those of keratohyalin and from those of amyloid or hyaline body. Also the keratinous cyst was associated with colloid bodies, showing the lamellated figure in the subepithelial area.

Adolescent↗
PubMed1991

Biphasic amyloidosis arising from friction melanosis.

A 40-year-old woman who had used nylon towels in the bath for about 10 years noticed hyperpigmentation on the prominent regions over the bones of the trunk and extremities. She also developed lichenoid papules with itching on her back. Histologically, both the pigmented and the papular lesions had amyloid deposits beneath the epidermis. In this case it is presumed that the papular lesions with amyloid (lichen amyloidosus) developed initially from friction melanosis which became macular pigmented lesion (macular amyloidosis). The etiologic factor of these sequential pathologic changes is considered to be repeated scrubbing with nylon towels.

Adult↗
PubMed1991

Persistent facial ulcerations with a unique clinical appearance: possible trigeminal trophic syndrome.

We reported a 53-year-old woman with a persistent facial ulcer which moved gradually from the right marginal portion of the nasal root to the right lateral canthus along the margin of the right lower eyelid. The ulcer healed spontaneously. A similar ulcer developed at the entrance of the right anterior naris. The clinical findings were suggestive of squamous cell carcinoma, deep mycosis, mycobacterial infection, or a related condition. However, no definitive diagnosis could be made from the clinicopathological findings or the laboratory examinations, including bacterial, mycobacterial, and fungal cultures. The characteristic location of the lesion, and course of the disease, however, suggested the diagnosis of trigeminal trophic syndrome.

Chronic Disease↗
PubMed1991

Lichen nitidus: a histologic and electron microscopic study.

A lesion of lichen nitidus in a 53-year-old man was examined by histology and electron microscopy. The histology showed typical features. The electron microscopy revealed primary changes in hydropic degeneration of basal cells which possibly indicated severe edema between the basal keratinocytes and in the subepidermal area. The basal keratinocytes themselves were not particularly altered, except for clustered micro-vacuolar structures in a small portion of the peripheral cytoplasm. In one of the eight blocks observed, the cytoplasmic process of a mast cell was found between the basal keratinocytes, indicating that mast cells may possibly infiltrate the epidermis in lichen nitidus. Scattered mast cells in the dermis were also noted. Thus primary pathologic changes of lichen nitidus may be induced by severe edema, which was accompanied by inflammatory cells including mast cells, in the region of the dermal-epidermal junction.

Atrophy↗
PubMed1991

Linear focal elastosis. An ultrastructural study.

We studied an 86-year-old Japanese man with linear focal elastosis. The lesions were asymptomatic yellow striae in the lumbar region, histologically composed of massive, well-demarcated basophilic fibers that stained positively with elastic tissue stains. Electron microscopy revealed fine, reticular or granular electron-dense materials, and elastic fiber microfibril-like materials in the matrix, in addition to numerous mature and immature elastic fibers. These findings suggest that active elastogenesis was occurring in the lesions. The four cases reported so far have the three common features of age, sex, and lesion location.

Actin Cytoskeleton↗
PubMed1990

The local recurrence of pigmented Spitz nevus after removal.

A seventeen-month-old female had a pigmented nodule on her left lower leg. The excised lesion was histologically diagnosed as a Spitz nevus, composed mainly of spindle-shaped melanocytes containing large amounts of melanin pigment. When nodular regrowth was seen at the operative site, the recurrent lesion was radically excised as nodular melanoma. However the histological characteristics of the second excised specimen were essentially the same as those in the initially excised one except for the existence of the newly formed collagen fibers, which may suggest an involuting stage in the central portion of the lesion.

Diagnosis, Differential↗
PubMed1990

Organic acid and acylcarnitine profiles of glutaric aciduria type I.

Urinary organic acid and acylcarnitine profiles from a 2-month-old boy were studied by gas chromatography-mass spectrometry and fast atom bombardment mass spectrometry. The patient excreted large amounts of glutaric acid and significant amounts of 3-hydroxyglutaric acid, glutaconic acid and glutarylcarnitine, and his serum glutaric acid level was markedly elevated. Thus he was chemically diagnosed as having glutaric aciduria type I (GAI). In addition to the above metabolites previously described in GAI, significantly increased excretion of 2-ketoglutaric acid, succinic acid, adipic acid, adipylcarnitine, suberic acid and azelaic acid was found. 2-Ketoadipic acid methylsuccinic acid and ethylmalonic acid were also detectable, suberylcarnitine was not increased, and dehydroadipylcarnitine was decreased in his urine. These results suggest that excess glutaryl-CoA causes the competitive inhibition of the dehydrogenation of adipyl-CoA to dehydroadipyl-CoA and results in an increase of adipic acid and adipylcarnitine and a decrease of dehydroadipylcarnitine. It is also suggested that oxidative decarboxylation of 2-ketoglutaric acid to succinyl-CoA is inhibited by high levels of glutaryl-CoA, and that the dehydrogenation of succinic acid to fumaric acid is inhibited owing to the increased glutaric acid derived from excess glutaryl-CoA. These results indicate that gas chromatography-mass spectrometry is the most appropriate and accurate method for the differential chemical diagnosis of GAI and glutaric aciduria type II.

Acylation↗
PubMed1990

A case of secondary cutaneous amyloidosis: epidermal keratinocytes produce amyloid in the cytoplasm.

A case of secondary localized cutaneous amyloidosis associated with a seborrheic keratosis is reported. Amyloid was observed both in the stroma and in the tumor. Light and electron microscopy revealed amyloid within the cytoplasm of the tumor cells. This intracytoplasmic amyloid was seen in basaloid cells or in the border areas between basaloid cells and squamous cells, but it was not seen in squamous cells. The amyloid was positive for anti-keratin antibody and contained disulfide bonds. It is suggested that either abnormal keratinization or the degeneration of basaloid cells produced abnormal keratin proteins that formed this amyloid.

Aged↗
PubMed1990

Acantholytic pilomatricoma.

An 11-year-old girl had a slowly enlarging, painful, pink-red tumor on her scalp of 1 month's duration. The lesion was composed of several, round tumor cell nests in the dermis. Each nest was made up of peripheral basophilic cells and central shadow cells or eosinophilic materials. Occasionally the nests, having central eosinophilic degeneration, became epithelial cysts, some of which showed acantholytic changes in their cyst wall. This seems to be the first case of an acantholytic variant of pilomatricoma.

Acanthocytes↗