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Biomedical subjects

T Kobayasi

Publications and source records attributed to T Kobayasi.

At least 37 records · Page 2Linked to original sources
PubMed1988

Fiberoptic bronchoscopy and bronchial mucosal biopsies in asthmatics undergoing long-term high-dose budesonide aerosol treatment.

Mucosal biopsies from the pharynx, right main stem bronchus and right lower lobe were obtained during flexible fiberoptic bronchoscopy and were examined with light microscopy (LM) and electron microscopy (EM) in 10 asthmatics after 11 months' (range 7-15 months) treatment with high doses of inhaled budesonide via the Nebuhaler, i.e. 1600 micrograms daily. Results were compared with biopsies from 10 controls suspected of having focal, malignant lung diseases. Visual inspection of the tracheobronchial tree showed no signs of atrophy, ulcerations or thrush patches, and LM and EM showed no specific signs of mucosa and connective tissue atrophy; however, epithelial desquamation was seen in the asthmatics. No complications were observed.

Adolescent↗
PubMed1988

Ultrastructure of angiokeratoma vulvae.

A case of vulvar angiokeratoma studied by electron microscopy is described. The patient, a 51-year-old woman, had noticed eruptions for the last 15 years, though without symptoms. Osmiophilic bodies with myelin-like figures were found in the vascular endothelial cells. The findings support previous opinion that vulvar angiokeratoma is a variant of scrotal angiokeratoma.

Angiokeratoma↗
PubMed1988

Treponema pallidum in leukoderma syphiliticum demonstrated by electron microscopy.

Punch biopsies from syphilitic leukoderma lesions and from unaffected skin in 3 patients with secondary syphilis were studies in the transmission electron microscope. In one of the patients the pigment disorder was not preceded by any visible syphilids, and in the biopsy from the leukodermal skin in this patient Treponemata pallidium were demonstrated around vessels and inside nerve fibres in which the myelin sheaths of the axons showed evidence of degeneration. In the other 2 patients the depigmented areas appeared while macular and papular syphilitic lesions were healing. In the biopsies from the leukodermal lesions of these 2 patients and from unaffected skin of all 3 patients, no treponemes were demonstrated. The study indicates that syphilitic leukoderma is not invariably a post-inflammatory phenomenon, but the pigmented skin lesions may themselves represent stigmata of an active syphilitic infection.

Adult↗
PubMed1987

Ultrastructure of the small intestinal mucosa in progressive systemic sclerosis (PSS).

The present study deals with ultrastructural changes of jejunal absorptive epithelium in mucosal biopsy specimens from eleven patients with progressive systemic sclerosis (PSS). Epithelial cells showed cytoplasmic condensations with cholesterol clefts and fat droplets. Intercellular spaces of the epithelium were dilated with deposits of fat droplets, while tight junctions and villi preserved their normal structures. Goblet cells and entero-endocrine cells showed no changes. In the lamina propria, fat droplets were observed as well. Vessels were strongly dilated and in 2 patients contained conglomerates of thrombocytes. Perivascular cell infiltrates consisted of lymphocytes, macrophages and mast cells, while plasma cells were scarcely seen; in 2 patients, plasma cells were abundant. Collagen fibrils, elastic fibres, and nerves showed no definite changes. The findings of epithelial cell degeneration and fat droplet deposits indicate dysfunction of jejunal absorptive epithelial cells in PSS.

Adult↗
PubMed1987

Ultrastructural changes of Treponema pallidum isolated from secondary syphilitic skin lesions.

Treponema pallidum was isolated from various types of secondary syphilitic skin lesions. From moist genital papules and from condylomata lata several treponemes were isolated whereas few were isolated from dry papules of the trunk. One third of the observed treponemes were morphologically different from treponemes isolated from human chancres. Especially the nose-piece structures of the terminal parts of the treponemes were deviating. Some nose-pieces were coated by a fuzzily outlined electron dense substance, whereas others were degenerated or nearly separated from the cytoplasmic body. Other treponemes were missing their nose-piece as avirulent saprophytic treponemes. Recent studies have indicated that the nose-pieces are essential for the tissue attachment of treponemes and the treponemal virulence. The significance of the altered nose-piece structure observed is discussed.

Adult↗
PubMed1986

Treponema pallidum in macular and papular secondary syphilitic skin eruptions.

The ultrastructure of biopsies from dry macular and papular secondary syphilitic skin lesions of 10 patients were studied by electron microscopy. In all biopsies few diffusely distributed treponemes were observed. This may explain the difficulties in demonstrating treponemes by darkfield examination of tissue fluid from dry secondary syphilitic skin lesions. The outlines of treponemes were less distinct as compared to those of primary syphilis. The periplastic membranes were almost invariably absent and the cytoplasmic membranes appeared in close contact with an enclosing layer of irregularly demarcated, electron dense amorphous substance. This substance may be a manifestation of the immune reaction of the host cells to the treponemes. Degenerations were noted in both unmyelinated and myelinated nerve tissue. This accounts for the fact that skin lesions in secondary syphilis are usually without symptoms. Also in the vessel walls treponemes were demonstrated. The vascular endothelial cells were proliferating and the basement membranes were multilaminated and split.

Endothelium↗
PubMed1986

Treponema pallidum in human chancre tissue: an electron microscopic survey.

In biopsies obtained from syphilitic chancres of varying ages in 10 patients, a total of 766 ultrathin sections of Treponema pallidum were studied by electron microscopy. The course and number of axial filaments observed reveal that one bunch of 3-4 filaments without interruption entwine the whole cytoplasmic body. In 9.2% of the sections a trilaminar or a fragmentary trilaminar periplastic membrane was observed outside the cytoplasmic membrane and the axial filaments. The occurrence of the periplastic membrane decreased with advancing ages of the chancres. A protective function of the membrane is discussed. A peritreponemal fine reticular halo demonstrable in most fragments is supposed to be due to fixation induced shrinkage of treponemal hyaluronidase-influenced semifluid glycosaminoglycans. Peritreponemal reticular halos were also observed in collagen tissue. A destructive effect of the treponemes on collagen fibres could explain how the organisms penetrate through the collagen rich meninges into the central nervous system. A surface associated narrow border of electron dense amorphous substance, probably originating from the host organism, yields to tangentially cut treponemes a spiny caterpillar-like appearance.

Cell Membrane↗
PubMed1985

Filamentous aggregates of collagen. Ultrastructural evidence for collagen-fibril degradation in situ.

Filamentous aggregates of collagen are distinct structures in the pathological dermis. These aggregates are distinguishable from fibrous long-spacing collagen (in vitro and at biopsy) and the Luse body. The aggregates are produced from dermal collagen fibrils by clostridial collagenase and culture-medium extract, which supposedly contains cellular collagenase at a neutral pH, as well as by organ cultures. In vitro experiments showed that carrageenan granuloma contains fibrous long-spacing collagen and segment long-spacing collagen. The granuloma also contains the aggregates. The aggregates were found in skin biopsies from syphilitic chancres, acrosclerotic scleroderma, morphea, mycosis fungoides, myeloid leukemia, mastocytosis and malignant melanoma. These findings indicate that the aggregates are products of the in situ degradation of collagen fibrils by some collagenolytic factor. This factor may originate in fibroblast-like cells, reticulum cells, leukemia cells, mast cells and melanoma cells.

Biopsy↗
PubMed1985

Secretion of type IV collagen by keratinocytes of human adult.

Secretion of type IV collagen by keratinocytes was studied by anti-type IV collagen immunoglobulin in pure keratinocyte culture of the human adult. The cultivated keratinocytes secreted type IV collagen into the space between the cell growth and the underlying fixed film of human skin collagen type I. The secreted collagen was accumulated on the cell surface to form junction structures.

Adult↗
PubMed1985

Vascular changes in morphea.

Vascular changes in morphea were studied in skin biopsies from 14 patients. Small vessels with pericytes present the changes in three different patterns. The first was the endothelial cells in a stimulated condition and thickened vascular wall with infiltrating macrophages and mast cells. The second was characterized by thick basal lamina of pericytes and the third by activated pericytes with infiltrating lymphocytes and plasma cells. Otherwise, all patterns showed altered endothelial cells and infiltrating macrophages and mast cells similar to the first pattern. The first pattern was mostly found in uninvolved skin. The second and the third were found in the inflammatory and sclerotic areas. It seems, therefore, that activated pericytes are the most essential changes in vessels of morphea. Probably, muscular vessels are simply involved in the fibrotic process.

Adolescent↗
PubMed1985

The ultrastructure of treponema pallidum isolated from human chancres. Morphologic variations from Nichols' strain.

The ultrastructure of treponema pallidum obtained directly from human chancres by biopsy was studied by electron microscopy. The treponemes were enveloped by a trilaminar cytoplasmic membrane and a trilaminar periplastic membrane. The central part of the periplastic membrane corresponds to the protective mucoid layer. In undamaged organisms bunches of axial filaments were seen to entwine the whole cytoplasmic body without any disruption or overlapping. The number of axial filaments varied between three and four. Identical nose pieces were demonstrable in both ends of the treponemes. Axial filaments and nose pieces seem to differ from those of Nichols' strain.

Chancre↗
PubMed1985

Pityriasis rosea eruption in secondary syphilis: an isomorphic phenomenon?

A 41-year-old man was referred because of a slightly pruritic eruption, and a classic case of pityriasis rosea was diagnosed on the first examination. Results of routine tests for syphilis were strongly positive, and on repeated examination the eruption had grown further. Skin biopsy specimens showed plasma cells and Treponema pallidum. All symptoms disappeared following antisyphilitic treatment. The possibility of an isomorphic response is discussed.

Adult↗
PubMed1984

Dermal changes in Ehlers-Danlos syndrome.

Skin biopsies from thirteen patients suffering from Ehlers-Danlos syndrome, including 6 of the mitis type, 4 of the benign hypermobile type, one of the X-linked type, one of the ocular type and one of the periodontitis type, were studied by electron microscopy after routine preparation. Collagen fibrils showed a distorted arrangement of bent, curled or twisted fibrils and thread-like material. Similar changes may be seen in the skin of other hereditary disorders of connective tissue. However, abnormal collagen fibrils in normal skin suggests one of eight types of Ehlers-Danlos syndrome. Clinical variants cannot be differentiated on the basis of ultrastructural findings. Elastic fibres were normal without degenerative changes. Perineurium was lacking in dermal nerves of most patients. Fibroblast-like cells showed no cystic cisterna of endoplasmic reticula.

Adult↗
PubMed1984

Significance of the equilibrium constant between serum ascorbate radical and ascorbic acids in man.

The spin concentration of ascorbate radical in human serum was examined and the existence of the stable equilibrium between the spin concentration of serum ascorbate radical and concentrations of ascorbic acids in healthy subjects was found. The value of the equilibrium constant was independent of age and sex. The administration of ascorbic acid caused the convergence of these values which were scattered within certain ranges in healthy volunteers. The values of the equilibrium constant increased in many patients with various diseases and returned to normal level with improvement of symptoms. These indicate that the equilibrium constant can be used as a clinical index to reflect metabolic state involving ascorbic acid as the radical scavenger.

Ascorbic Acid↗
PubMed1984

Pseudo-Kaposi sarcoma of the feet: an electron microscopic investigation.

A case of pseudo-Kaposi sarcoma of the feet (acroangiodermatitis) is reported. The patient showed clinical and light-microscopic signs closely resembling Kaposi's sarcoma, but by electron microscopy of skin biopsies definite signs of degeneration of vascular walls and infiltrating cells were demonstrated. Electron microscopy should be applied when conventional histology is inconclusive or fits poorly to the anamnestic information and/or clinical appearance of the lesions.

Acrodermatitis↗