PubMed Health⌕ Search

Biomedical subjects

H Tagami

Publications and source records attributed to H Tagami.

At least 163 records · Page 9Linked to original sources

Acrokeratosis paraneoplastica (Bazex syndrome) associated with primary cutaneous squamous cell carcinoma of the lower leg, vitiligo and alopecia areata.

We report a case of acrokeratosis paraneoplastica (AP; Bazex syndrome), characterized by typical palmoplantar hyperkeratosis and psoriasiform scaly erythema of the acral regions, associated with primary cutaneous squamous cell carcinoma (SCC) on the left lower leg. This 54-year-old Japanese man subsequently developed vitiligo, and alopecia areata of the scalp. Serial monitoring of squamous cell carcinoma antigen (SCC-Ag) demonstrated that the severity of the clinical manifestations of AP paralleled the serum concentrations of SCC-Ag. We suggest that an immune-mediated mechanism underlies the development of AP in this patient.

Alopecia Areata↗

Glucose lowers CRP* levels resulting in repression of the lac operon in cells lacking cAMP.

CRP-cAMP-dependent operons of Escherichia coli can be expressed in cells lacking functional adenylate cyclase when they carry a second-site mutation in the crp gene (crp*). It is known that the expression of these operons is repressed by glucose, but the molecular mechanism underlying this cAMP-independent catabolite repression has been a long-standing mystery. Here we address the question of how glucose inhibits the expression of beta-galactosidase in the absence of cAMP. We have isolated several mutations in the crp gene that confer a CRP* phenotype. The expression of beta-galactosidase is reduced by glucose in cells carrying these mutations. Using Western blotting and/or SDS-PAGE analysis, we demonstrate that glucose lowers the cellular concentration of CRP* through a reduction in crp* mRNA levels. The level of CRP* protein correlates with beta-galactosidase activity. When the crp promoter is replaced with the bla promoter, the inhibitory effect of glucose on crp* expression is virtually abolished. These data strongly suggest that the lowered level of CRP* caused by glucose mediates catabolite repression in cya- crp* cells and that the autoregulatory circuit of the crp gene is involved in the down-regulation of CRP* expression by glucose.

Adenylyl Cyclases↗

Ichthyosiform eruption in a patient with Dubowitz syndrome.

Dubowitz syndrome is a rare autosomal recessive disorder characterized by intrauterine and postnatal growth retardation, microcephaly, moderate mental retardation, typical craniofacial anomalies, and eczematous skin lesions. We report a case of Dubowitz syndrome associated with ichthyosiform skin changes.

Child, Preschool↗

Detection of point mutations in human tyrosinase gene by improved allele-specific amplification.

Allele-specific amplification (ASA) is a simple and non-radioactive technique for detecting known point mutations that produce genetic diseases. Although this technique is based on the specific amplification of the target allele by a polymerase chain reaction (PCR) with allele-specific primers, the specificity of the amplification may depend on various PCR conditions. To avoid non-specific amplification which leads to false-positive results in ASA, we modified both the normal and mutant allele-specific primers so that they would have one constant base mismatch, located at the penultimate 3' position. We confirmed that our modification could inhibit such unfavorable amplification by using as templates genomic DNAs of patients affected with tyrosinase-negative oculocutaneous albinism (OCA). We then analyzed new patients affected with tyrosinase-negative OCA, and based the diagnosis on both the results of a clinical examination and those of a hair bulb test using ASA with the modified allele-specific primers. The results indicated that more than 3 alleles of the tyrosinase gene with a pathological mutation existed in Japanese patients.

Albinism, Oculocutaneous↗

Prurigo nodularis consists of two distinct forms: early-onset atopic and late-onset non-atopic.

BACKGROUND: Prurigo nodularis (PN) is a characteristic chronic dermatosis of unknown etiology showing severely pruritic nodules mainly on the extremities. Atopic diathesis has been implicated as a contributing factor. OBJECTIVE: Our purpose was to analyze the role of environmental allergens from living organisms in the pathogenesis of PN, to report hypersensitivity against various environmental allergens and to relate this to atopic history in 31 PN patients. METHODS: Positive and negative controls were studied including 52 patients with atopic dermatitis (AD) and 22 healthy controls. RAST, prick tests and scarification patch tests were performed on the patients and specimens from lesions of 8 patients were stained with anti-eosinophil cationic protein (ECP) antibody. RESULTS: The 31 PN patients were divided into two groups, those with a past or present history of AD (PN + AD patients) and those without (PN-only patients). Twenty patients (65%) had PN + AD (median age at onset 19 years) and 11 (35%) had PN only (median age at onset 48 years). Analyses of serum IgE levels. RAST scores, prick test and scarification patch test results revealed that the PN + AD patients showed hypersensitive reactions to the environmental allergens in a pattern almost identical to that noted in AD without PN. In contrast, most of those with PN only did not show any hypersensitivity reactions to the environmental allergens. Histologically, many activated eosinophils, identified by monoclonal antibody to ECP, were observed only in the dermis of the PN+AD patients, in contrast to few eosinophils in the lesion of PN-only patients. CONCLUSIONS: These results indicate that there are two forms of PN: an atopic and a non-atopic one. The PN+AD group is closely associated with AD, being accompanied by cutaneous hypersensitivity to various environmental allergens (a pattern similar to that displayed by AD patients) and has a younger age of onset, whereas the PN-only group, which showed a much older age of onset, does not show any such hypersensitive reactions against these allergens.

Adolescent↗

Differential effects of selective beta 1-agonist stimulation on epi- and endocardial oxygen tension in anesthetized dogs.

We investigated the effects of selective beta 1 adrenoceptor stimulation on oxygen tension (pO2) in the myocardium of anesthetized dogs. A beta 1-selective full agonist, T-0509 (0.01-0.05 microgram/kg, i.v.), caused positive inotropic and chronotropic effects, and increased left circumflex blood flow, although it did not change arterial blood pressure. These effects were inhibited by bisoprolol (10 micrograms/kg), but not by ICI 118551 (30 micrograms/kg). Under control conditions, subepicardial pO2 (pO2 epi) and subendocardial pO2 (pO2endo) were approximately 33 and 27 mmHg, respectively. T-0509 (0.05 microgram/kg) decreased pO2epi in all cases, with a mean decrease of 2.6 +/- 0.5 mmHg, and this was significantly inhibited by bisoprolol. T-0509 caused an increase (7 out of 10 dogs) or a slight decrease (3 out of 10) in the pO2endo; the mean increment was 2.0 +/- 1.3 mmHg (n = 10). Isoproterenol (0.01-0.05 microgram/kg, i.v.) exerted positive inotropic and chronotropic effects that were sensitive to bisoprolol, and a hypotensive effect that was sensitive to ICI 118551. Isoproterenol caused an increase in blood flow that was sensitive to ICI 118551. Isoproterenol (0.05 microgram/kg) decreased pO2epi in all cases, with a mean decrease of 2.7 +/- 0.5 mmHg, which was significantly inhibited by bisoprolol. Isoproterenol caused an increase (5 out of 10) or a slight decrease (5 out of 10) in the pO2endo; the mean increment was 1.1 +/- 1.2 mmHg (n = 10).(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenergic beta-1 Receptor Agonists↗

Proinflammatory properties of molluscum bodies.

Molluscum contagiosum, a condition characterized by benign viral tumours, occasionally becomes inflamed and regresses spontaneously, an event probably initiated by a host cell-mediated immune rejection against the lesion, but it inevitably involves the disruption of the epidermal tissue to expose the molluscum bodies to the tissue fluids of the dermis. It has been suggested that the molluscum bodies induce inflammation by a mechanism similar to that involved in ruptured epidermal cysts or in acne. Despite the occasional development of inflammation in molluscum contagiosum, the proinflammatory properties of molluscum bodies have never been studied in vitro. Thus, in the present study we sought to determine whether molluscum bodies exert a proinflammatory effect by inducing neutrophil chemotaxis. When exposed to fresh serum in vitro, water-insoluble components of molluscum bodies activated the alternative complement pathway to produce chemotactic C5a/C5a des Arg. We also found that an aqueous extract of molluscum bodies exerted potent chemotactic activity for neutrophils. Remarkably high amounts of the immunoreactive proinflammatory cytokines IL-8 and GRO alpha were present in the extract even when compared with psoriatic scale extracts. Gel filtration HPLC of the extract demonstrated the presence of neutrophil chemotactic activity over a wide range of molecular mass. These data suggest that disruption of the epidermal wall of molluscum bodies induces acute inflammatory changes by activation of the alternative complement pathway on exposure to the tissue fluids, and that the molluscum bodies themselves release proinflammatory cytokines and other neutrophil chemotactic factors on decomposition.

Chemotaxis, Leukocyte↗

Immunoelectron microscopic localization of fibronectin in cultured human keratinocytes.

We investigated the ultrastructural localization of fibronectin (FN) in cultured human keratinocytes using an improved method of peroxidase-immunoelectron microscopy. This method enabled us to visualize the precise localization of FN within the cells while preserving the morphology. FN was localized in the protein synthetic and secretory organelles, including the rough-surfaced endoplasmic reticulum, Golgi complex, multivesicular bodies and perinuclear space. It was also detected in the extracellular space, on small regions of the villous projections of cell membranes at the site of secretion and at cell-substratum contact sites. These findings confirm that human keratinocytes synthesize, secrete and deposit FN in the pericellular matrix.

Cells, Cultured↗

Long-term follow-up study of changes in lipid peroxide levels and the activity of superoxide dismutase, catalase and glutathione peroxidase in mouse skin after acute and chronic UV irradiation.

Lipid peroxide levels, the activities of superoxide dismutase (SOD), catalase and glutathione peroxidase (GSH-Px), and the development of tanning in the skin of C57 BL/6 mice were assessed for long periods, from very early to late stages, after acute or chronic UVB irradiation. Acute UVB irradiation produced an increase in lipid peroxide levels that peaked 18 h after irradiation, after which the levels declined to a minimum 2-3 days after irradiation and then gradually rose to baseline. Chronic irradiation caused the lipid peroxide level to fall to a minimum at 0.5-1.0 weeks, after which it gradually returned to baseline by the third week. SOD and GSH-Px activities decreased sharply after acute irradiation, reaching a minimum 18 h after irradiation. Following chronic irradiation, these enzyme levels peaked after 0.5 weeks, and thereafter declined gradually to the original levels 3 weeks after irradiation. In contrast, catalase activity did not change significantly. Tanning began to increase at 1.5 weeks after irradiation, with an accelerated rate of increase from the third week.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Primary cutaneous B-cell lymphomas in Japan. A report of three cases and a comparison of Japanese and white patients.

BACKGROUND: In contrast to cutaneous T-cell lymphoma, primary cutaneous B-cell lymphomas (pCBCL) are rare in Japan. Thus there have been no reports in the English literature that analyze Japanese pCBCL cases in detail. OBJECTIVE: We describe three additional Japanese cases of pCBCL and review the Japanese literature to compare their clinical features and prognoses with those in cases that involve white persons. METHODS: In our three cases, we performed immunohistochemical and flow cytometric analyses to determine the phenotypes of tumor cells. Genotypic analysis was also conducted by Southern blotting. In addition, we reviewed 43 cases of pCBCL reported in Japan. RESULTS: In our three cases of pCBCL, the lack of systemic involvement indicated that they were primary cutaneous tumors. One of our cases, which had a poor prognosis, lacked both HLA-DR and CD44 phenotypes, which are usually observed in the diffuse large-cell type of pCBCL. We found three major differences between the reported Japanese cases including ours and the cases that involved white persons: (1) histologically, the diffuse type was presented in 79% of lesions of less than 12 months' duration in the Japanese cases but in only 9% of lesions in white persons; (2) chemotherapy was more frequently selected in the Japanese cases (51%), whereas radiotherapy was used more frequently in white cases (71%); and (3) the death rate from pCBCL was much higher in Japanese (16%) than in white (2%) persons. CONCLUSION: pCBCL in Japanese persons seems to be different from that in white persons in frequency, in histoarchitectural growth pattern, and in prognosis.

Aged↗