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Biomedical subjects

H Tagami

Publications and source records attributed to H Tagami.

At least 325 records · Page 18Linked to original sources
PubMed1987

Psoriasis and leukocyte chemotaxis.

Transepidermal migration of leukocytes, with resultant formation of microscopic or macroscopic sterile subcorneal pustules is a phenomenon characteristically noted in psoriasis and related sterile pustular dermatoses. It is natural to assume the presence of potent neutrophil chemotactic substances in the subcorneal portion of the lesional epidermis, because this location is the target of the in vivo leukocyte chemotaxis. In fact, crude psoriasis scale extracts show remarkably high neutrophil chemotactic and activating properties as compared with those of other non-psoriatic inflammatory dermatoses. We isolated a psoriatic leukotactic factor (PLF) having a molecular mass of around 12 kD, distinct from those common to other inflammatory changes involving the skin or those released by bacteria. Further analysis of PLF identified C5 cleavage fragments, together with other chemotactic peptides, such as those derived from monocytes. Likewise, potent low-molecular-mass chemotactic factors, including cell membrane lipid derived chemotactic factor, e.g. leukotriene B4, are also increased in psoriatic lesions, as in other nonpsoriatic inflammatory dermatoses. However, their activity to stimulate the generation of oxygen radicals in neutrophils was found to be much weaker than that of PLF. The peripheral blood leukocytes from active psoriatic patients show enhanced function in chemotaxis, phagocytosis, active oxygen production, and enzyme release; patients' sera contain substances such as anaphylatoxins that activate leukocyte function. Further research is required for clearer understanding of the series of events resulting in the leukocyte chemotaxis, as well as for the elucidation of the background immunoregulatory mechanisms.

Cell Movement↗
PubMed1987

Effects of extracellular matrices on human keratinocyte adhesion and growth and on its secretion and deposition of fibronectin in culture.

Extracellular matrices (ECMs) play an important role as components of basement membrane of normal human skin and in migrating epidermal cells in wound healing. We investigated the effects of various ECMs on human keratinocyte adhesion and growth as well as on its secretion and deposition of fibronectin (FN) in vitro using a serum-free, low-calcium culture system. Since cell adhesion is the first step of cell growth, we performed cell adhesion assay for 14 h. Human keratinocytes adhered best on FN and less well on types I/III collagen, type IV collagen, and heparan sulfate proteoglycan (HSPG) as compared with bovine serum albumin (BSA) (control) or laminin (La). Cell growth assayed for 7-8 days on the dishes coated with various extracellular matrices revealed significantly increased keratinocyte growth on FN and on types I/III collagen in comparison with that on type IV collagen, HSPG, BSA (control), or La. Morphology of keratinocytes and of their colonies on FN and types I/III collagen was strikingly different from that of the control; the colonies were not so compact as in the control, but rather loose and larger; each keratinocyte was spread out more on these substrata. These morphologic features seemed to correlate with the increased keratinocyte growth on these extracellular matrices. Both immunofluorescence study for FN with keratinocytes in 8-day culture on various extracellular matrices and enzyme-linked immunosorbent assay for FN measurement on substratum or in conditioned medium with keratinocytes in 5-day culture demonstrated that extracellular matrices modulated the secretion and deposition of FN by human keratinocytes in culture; the keratinocyte growth correlated with the amount of FN detected on substratum but not with that in medium. Based on the results of the present investigation, we think that the growth of human keratinocytes depends on the amount of FN on substratum.

Cell Adhesion↗
PubMed1987

Stimulatory effect of prostaglandin E2 on the configuration of normal human melanocytes in vitro.

Normal human epidermal melanocytes became swollen and more dendritic when they were cultured for 6 days with prostaglandin (PG) E2, but not with PGE1, although the amount of immunoreactive tyrosinase in the melanocytes did not appear to be increased markedly after these treatments. From these data we suggest that PGE2 may be one of the factors responsible for the induction of postinflammatory hyperpigmentation of the skin.

Alprostadil↗
PubMed1987

HLA-DR antigen expression on keratinocytes in highly inflamed parts of psoriatic lesions.

We have investigated the immunoperoxidase staining pattern in the epidermis and dermal infiltrates of highly inflamed portions of psoriatic lesions, selecting for biopsy early pinpoint lesions or margins of active plaque lesions. We found positive intercellular staining for HLA-DR antigens in localized areas of the epidermis in about half of the patients tested. In contrast, OKT6 antigen was found only on the dendritic cells in the epidermis and dermis in all cases. These findings support the hypothesis that an active cellular immune reaction involving the epidermis, possibly associated with the expression of HLA-DR antigens on keratinocytes, occurs in the highly inflamed areas of psoriatic lesions, particularly in early pinpoint lesions or at the edges of spreading plaque lesions.

Dermatitis↗
PubMed1987

Geographic tongue in two siblings.

We report two illustrative cases of geographic tongue which occurred in 6- and 4-year-old sisters whose father had fissured tongue. The elder sister had mild atopic dermatitis and nail changes, but there was no family history suggestive of psoriasis. Histologically, the geographic tongue in the elder sister showed the same features as the oral lesions in pustular psoriasis. From a review of the literature we suggest that geographic tongue may be classified into two types, one that commonly occurs in atopics and another that develops as an oral manifestation of pustular psoriasis, although both types show similar histopathological features.

Child↗
PubMed1987

Plasma anaphylatoxin concentrations in inflammatory skin diseases.

To study the possible involvement of the complement system in inflammatory skin disorders, we measured the concentrations of C3a and C4a anaphylatoxins in the peripheral blood of 148 patients with various inflammatory skin disorders and 48 healthy control subjects by radioimmunoassay. Significant increases in mean levels of both C3a and C4a anaphylatoxins were found in 59 patients with psoriasis. Remarkable increases in both C3a and C4a anaphylatoxins were also noted in some patients with leukocytoclastic vasculitis, urticarial vasculitis or unspecified toxic erythema. On the other hand, elevation of C4a alone was noted in a case of systemic lupus erythematosus. In contrast, using the mean of the normal control +/- 2 S.D., no significant anaphylatoxin elevation was found in 16 patients with pustulosis palmaris et plantaris, 7 with pityriasis rosea, 3 with erythema multiforme, and 3 with erythema nodosum or autoimmune bullous dermatoses.

Anaphylatoxins↗
PubMed1987

Lucigenin-induced chemiluminescence in human neutrophils in the process of adherence and chemotactic migration measured in a modified Boyden chamber system.

To answer the question of whether an oxidative burst in neutrophils occurs in the process of adherence and chemotactic migration, we estimated their lucigenin-induced chemiluminescence (CL) responses in a specially devised Boyden chamber that utilized a vial for CL measurement. Neutrophils placed in the upper compartment immediately after isolation induced lucigenin-dependent CL even in the absence of chemotactic factors in the lower chamber, which was completely scavenged by superoxide dismutase at a concentration of 100 micrograms/ml. This response was suggested to be caused by neutrophils in the process of adherence to a filter. When formyl peptide (FMLP) or zymosan-activated serum (ZAS) was placed in the bottom compartment, they were effective to induce CL in the neutrophils already adhered to the membrane filter. These chemotactic factors induced light emission in neutrophils maximally at the concentration of 10(-7) M for FMLP and 5% for ZAS in the reaction mixture without any more increase in CL being observed above these concentrations. This makes a sharp contrast to the findings observed in the so far used unphysiological experimental system, in which neutrophils are abruptly exposed to chemotactic factors likewise in present study. When FMLP or ZAS was directly added to the cells in a upper compartment, CL increased dose-dependently from 10(-9) to 10(-5) M for FMLP, and from 5 to 50% for ZAS.(ABSTRACT TRUNCATED AT 250 WORDS)

Acridines↗
PubMed1987

Delayed tissue necrosis due to mitomycin C.

We report about a patient having received intravenous mitomycin C without evidence of tissue injury until three months following its extravasation. After drinking alcoholic beverages 3 months later he developed a severe ulcer at the site of the previous extravasation. There are only a few reports about such extravasation ulcers occurring a long time after the injection.

Humans↗
PubMed1987

Monoclonal antibody AHS-7 defines a specific basement membrane antigen localized to the hemidesmosome zone.

MoAb AHS-7 labels the basement membrane of the skin. In this report, we have determined the precise localization and molecular nature of the antigen(s). After epidermal-dermal separation by suction blistering, the antigen(s) were detected on the epidermal side. Immunoelectron microscopy revealed the reaction product observed as a discontinuous line along the plasma membrane of the basal keratinocytes, which corresponded to the distribution of the hemidesmosomes. We extracted the proteins from the normal human epidermis separated from the dermis by suction blistering. After being separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the proteins were electrophoretically transferred to nitrocellulose sheets, and the antigen(s) were identified by immunoperoxidase staining with MoAb AHS-7. We detected 4 protein bands of molecular weights of 82 kd, 104 kd, 120-135 kd, and 140-160 kd when unreduced, in contrast to only two bands of 41 kd and 52 kd when reduced. These data suggest that the antigen(s) recognized by MoAb AHS-7 defines a unique antigen, different from bullous pemphigoid antigen on the hemidesmosome zone.

Antibodies, Monoclonal↗
PubMed1987

Analysis of increased urinary acid glycosaminoglycans in a patient with relapsing polychondritis.

We analysed the composition of glycosaminoglycans (GAGs) found in an increased amount in the urine from a patient with relapsing polychondritis (RP) by means of electrophoresis, since to our knowledge no analytical studies on the composition of GAGs in the urine from the patients with RP have been performed. Unexpectedly, the major GAGs detected in increased amount in the urine were found to be dermatan sulfate (DS) and hyaluronic acid (HA), the excretion of which correlated with the activity of the disease. Both DS and HA are the major components not of the cartilage but of the skin. Therefore, our findings suggest that the increased GAGs in RP are derived from skin or other tissues containing these GAGs rather than from the cartilage, unless there is an extensive cartilage destruction.

Electrophoresis, Cellulose Acetate↗
PubMed1987

Antihypertensive effects of nisoldipine and reference drugs in certain types of hypertensive rats.

The hypotensive effects of nisoldipine (Bay K 5552), compared with those of nifedipine, nicardipine and hydralazine, in normotensive rats (NR), spontaneously hypertensive rats (SHR), DOCA-NaCl hypertensive rats (DNR) and renal hypertensive rats (RHR), were studied. The changes in plasma renin activity (PRA) after treatment with nisoldipine and these reference drugs were also studied. The results of this study revealed that: 1. Nisoldipine caused more potent antihypertensive effects in SHR, DNR and RHR than in NR. 2. The antihypertensive effects of nisoldipine in SHR were almost equipotent to those of nifedipine, nicardipine and hydralazine. However, in NR, DNR and RHR, the effects of nisoldipine were weaker than those of the reference drugs. 3. The positive chronotropic effects of nisoldipine were less remarkable than those elicited by nifedipine, nicardipine and hydralazine in all types of hypertensive rats, except SHR. 4. As did nifedipine and nicardipine, nisoldipine caused an increase of the plasma renin activity in NR and SHR, though its potency was weaker than those of nifedipine and nicardipine.

Animals↗
PubMed1986

Immunohistologic analysis of the phenomenon of spontaneous regression of numerous flat warts.

Among various tumors induced by human papilloma virus (HPV), flat warts are unique in that they show a systemic regression phenomenon after sudden occurrence of inflammation in all the tumors, leaving permanent immunity to flat warts in the host. When studied immunohistochemically, the presence of HPV antigen using papilloma virus genus-specific antiserum in 31 cases of regressing flat warts was not found; whereas it was demonstrated in the nuclei of upper epidermal cells of ordinary flat warts in 12 of 19 cases (63%). T-cell phenotype assessment in nine regressing flat warts using monoclonal antibodies showed that helper/inducer subsets constituted a major peritumoral dermal infiltrate with a moderate number of intermingling OKT6+ cells. In contrast, the tumoral epidermis was invaded by almost equal number of suppressor/cytotoxic T-cells and helper/inducer T-cells, where at least some keratinocytes also expressed HLA-DR antigen in addition to Langerhans cells. Most T-cells expressed HLA-DR antigen, a marker of activation, but only a small number of them were Tac antigen+, i.e., bearing interleukin 2 receptors. Leu 7+ natural killer cells were seldom found in the infiltrate. These data provide evidence that T-cell-mediated immune attack against tumor cells and not against intranuclear HPV antigen, induces the systemic spontaneous regression of numerous flat warts in humans.

Antigens, Viral↗
PubMed1986

Plane warts under spontaneous regression. Immunopathologic study on cellular constituents leading to the inflammatory reaction.

Immunohistologically, cellular infiltrates in regressing plane warts were mainly composed of lymphocytes and mononuclear phagocytes. There were many infiltrating T lymphocytes. Immunoelectron microscopic observation demonstrated that both helper/inducer and suppressor/cytotoxic phenotypes of T lymphocytes infiltrated in the lesions. OKT6-positive cells were observed in the dermis as well as in the epidermis. Moreover, as noted in allergic contact dermatitis, the apposition of T lymphocytes to Langerhans' cell-like cells could be seen. Lymphocytes and a small number of mononuclear phagocytes were found adjacent to damaged keratinocytes in the epidermis, the picture of which has been described as satellite cell necrosis, a hallmark of cytotoxic reaction by aggressors. These findings suggest that specific cell-mediated immunity against virus-infected keratinocytes takes place in the process of regressing plane warts.

Adolescent↗
PubMed1986

Changes in expression of Ia, Thy-1, and Ly-5 antigens in epidermal cells during delayed contact sensitivity reactions in mice: flow cytometric analysis.

Ia antigen-bearing (Ia+) Langerhans cells have attained an important position as immunocompetent cells in the epidermis. Recently there have been successive reports on other new possible candidates for immunocompetent cells in the epidermis, i.e., Ia+ keratinocytes and dendritic Thy-1 antigen-bearing (Thy-1+) epidermal cells which also express Ly-5 antigen and asialo-GM1. Based on our previous findings that in allergic contact sensitivity reactions, keratinocytes express Ia antigen 3-9 days postchallenge, in this report, we have attempted to define more clearly the dynamic changes of Ia+ keratinocytes and dendritic Thy-1+ epidermal cells by enumeration of the precise percentages of Ia+, Thy-1+, and Ly-5 antigen-bearing (Ly-5+) cells in epidermal cells at various times of the challenge phase in allergic contact sensitivity reactions by use of a fluorescence-activated cell sorter. By 24 h postchallenge, the percentages of Ia+, Thy-1+, and Ly-5+ cells showed hardly any change. There were approximately 2% Ia+ cells, 50% Thy-1+ cells which consist of 2 populations (i.e., 45% weakly Thy-1 antigen-positive cells and 4% strongly Thy-1 antigen-positive cells), and 3.5% Ly-5+ cells. From 48 h postchallenge, however, the percentage of Ia+ cells and that of Thy-1+ cells began to increase and reached a plateau, with approximately 20% Ia+ cells and 70% Thy-1+ cells, respectively, at 120 h postchallenge. The change of the percentages of Ly-5+ cells appears to correspond to that of strongly Thy-1 antigen-positive cells. Only at 48 h postchallenge, Ly-5+ cells and strongly Thy-1 antigen-positive cells showed a small increase in number, comprising approximately 10% of the epidermal cells. These data suggest that among Thy-1+ epidermal cells, strongly Thy-1 antigen-positive cells correspond to dendritic Thy-1+ epidermal cells, and in contact sensitivity reactions in mice, dendritic Thy-1+ epidermal cells show only a minor dynamic change in contrast to Ia+ cells, in which more than 15% of keratinocytes express Ia antigen from 48 h postchallenge.

Animals↗