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Biomedical subjects

H Okochi

Publications and source records attributed to H Okochi.

At least 19 recordsLinked to original sources
PubMed2006

Serum levels of BAFF are increased in bullous pemphigoid but not in pemphigus vulgaris.

BACKGROUND: BAFF [B-cell activating factor belonging to the tumour necrosis factor (TNF) family] is a member of the TNF superfamily that regulates B-lymphocyte proliferation and survival. It has been demonstrated that increased levels of soluble BAFF are associated with systemic autoimmunity in patients with systemic lupus erythematosus, rheumatoid arthritis and Sjögren's syndrome, and in animal models of spontaneous autoimmune diseases. However, the significance of circulating BAFF in autoimmune bullous diseases is unknown. OBJECTIVES: To examine whether BAFF levels are elevated in the autoimmune blistering diseases pemphigus vulgaris (PV) and bullous pemphigoid (BP). METHODS: We examined sera obtained from 21 patients with PV, 39 patients with BP and 22 healthy donors. We performed enzyme-linked immunosorbent assays for soluble BAFF and each disease-specific antibody: antidesmoglein-3 antibody for PV and anti-BP180 antibody for BP. RESULTS: Significant elevations of serum BAFF levels were found in the patients with BP, but not with PV. There was apparently no significant association between the serum BAFF levels and titres of anti-BP180 antibodies in the patients with BP. However, serum BAFF levels tended to be more elevated in patients with a shorter disease duration. There was a tendency that BAFF levels increased before the anti-BP180 antibody levels increased at the onset of BP and quickly decreased in response to treatment. CONCLUSIONS: BAFF may be a useful marker for early activation of an autoimmune diathesis and may play a critical role in triggering activation of self-antigen-driven autoreactive B cells in BP.

Adult↗
PubMed2005

Long-term culture of adult murine epidermal keratinocytes.

BACKGROUND: Long-term cultures of epidermal cells from mouse skin have been notoriously difficult to establish. OBJECTIVES: To develop a modified serum-free medium and technique for long-term culture of adult mouse epidermal keratinocytes. METHODS: Epidermal cells from trypsin-treated adult mouse dorsal and ventral skin were grown on type I collagen-coated dishes without feeder layers in a serum-free medium supplemented with only 10 ng mL(-1) epidermal growth factor (EGF) and 10(-10) mol L(-1) cholera toxin (CT). RESULTS: After removing coexisting fibroblasts several times, we were able to obtain almost pure basal epidermal keratinocytes. Our technique supports sustained multiplication of mouse basal keratinocytes for more than 100 population doublings, and they retained the capacity to undergo terminal differentiation when given the appropriate stimulus. The epithelial nature of these cultivated cells was demonstrated both by phase-contrast microscopy and by immunostaining with antikeratin antibodies. EGF and CT, which have been reported to accelerate the cellular growth rate, were essential for successful long-term cultivation during multiple passages. CONCLUSIONS: Our technique is very simple. It provides a useful and suitable model for investigations of growth, differentiation and skin remodelling in vitro.

Animals↗
PubMed2003

An in vitro interethnic comparison of monoamine oxidase activities between Japanese and Caucasian livers using rizatriptan, a serotonin receptor 1B/1D agonist, as a model drug.

AIMS: Monoamine oxidase (MAO) is located in human liver, and catalyses the oxidative deamination step of many xenobiotics. However, whether there exists an interethnic difference in MAO activities has, to our knowledge, not been clarified. We aimed to assess the MAO type A (MAO-A) involvement in the metabolic pathway of rizatriptan (RIZ), an antimigraine 5-hydroxytryptamine (5-HT)1B/1D agonist, and the interethnic difference in MAO activities between Caucasians and Japanese using RIZ as a model drug in in vitro experiments. METHODS: Oxidative deaminase activities were determined with the subcellular fractions of Japanese livers and the microsomal fraction of Caucasian livers using RIZ, 5-HT (MAO-A substrate) and 2-phenylethylamine (PEA) (MAO-B substrate) as substrates. RESULTS: The oxidative deaminase activities of RIZ vs. 5-HT were highly (r = 0.87 and 0.96, P < 0.001) correlated with each other in both the microsomal and mitochondrial fractions of Japanese livers. Subsequent results were obtained from in vitro experiments using liver microsomes based upon these findings. The oxidative deaminase activities of RIZ were inhibited completely by the nanomolar-order concentration of clorgyline and Ro 41-1049 (MAO-A selective inhibitors), but not by that of Ro 16-6491 (MAO-B selective inhibitor). The majority of the mean Michaelis-Menten values for three substrates toward MAO obtained from six Japanese and six Caucasian liver microsomes reached no significant differences between the two ethnic groups. The mean microsomal oxidative deaminase activities assessed in 18 Japanese and 20 Caucasian livers using the three substrates also showed no significant differences between the two ethnic groups. CONCLUSIONS: RIZ is mainly metabolized by MAO-A and the in vitro oxidative deaminase activities mediated via MAO-A and -B do not appear to differ between Japanese and Caucasians.

Asian People↗
PubMed2002

Does Hermansky-Pudlak syndrome predispose to systemic lupus erythematosus?

We report a Japanese patient with Hermansky-Pudlak syndrome (HPS) who developed systemic lupus erythematosus (SLE). This is the second case report of HPS complicated with SLE. A 1-bp duplication of adenine at codon 441 was found in the HPS gene, namely HPS1, which caused a frameshift. This case serves as evidence indicating that a patient with HPS can be predisposed to SLE.

Adult↗
PubMed2002

Analysis of the expression of cutaneous lymphocyte-associated antigen on the peripheral blood and cutaneous lymphocytes of alopecia areata patients.

Alopecia areata has been reported to be accompanied by abnormal autoimmune dysfunction. We examined the expression of cutaneous lymphocyte-associated antigen (CLA), which is a skin-specific lymphocyte homing receptor, in the peripheral blood lymphocytes and skin of patients with alopecia areata. In the patients' peripheral blood, the percentage of CLA-positive CD4+ or CD8+ lymphocytes, was significantly higher than that of normal controls. The patients with severe or progressive alopecia areata showed a much higher CLA-positivity compared to patients recovering from the disease. A chronological study showed that the percentage of CLA-positive peripheral blood lymphocytes, CD4 + or CD8 + lymphocytes decreased in parallel with the patients' good clinical course. The CLA-positivity in peripheral blood lymphocytes, CD4+ or CD8+ lymphocytes of patients with alopecia areata who did not respond to oral corticosteroid therapy remained higher than in those who responded well to the treatment. In the affected scalp skin, many infiltrating lymphocytes around the hair follicles, which were CD4+ or CD8+ lymphocytes, expressed CLA. These findings suggest that the CLA-positivity correlates with clinical activity and that CLA-positive CD4+ or CD8+ lymphocytes may play an important role in alopecia areata.

Adolescent↗
PubMed2001

Comparison of the kinetic disposition of and serum gastrin change by lansoprazole versus rabeprazole during an 8-day dosing scheme in relation to CYP2C19 polymorphism.

BACKGROUND: Little is known about differences in the disposition kinetics and pharmacological effects on gastrin levels between lansoprazole and rabeprazole given in a repeated dosing scheme with respect to the polymorphic CYP2C19. AIM: To provide preliminary information that should be considered when prescribing proton-pump inhibitors (PPIs) for the treatment of acid-related diseases with reference to the CYP2C/9 genotypic status. METHODS: Helicobacter pylori-negative healthy volunteers were divided into the following three groups (n = 5 each) on the basis of genotyping for CYP2C19: homozygous (hmEMs) and heterozygous extensive metabolizers (htEMs), and poor metabolizers (PMs). All received once-daily 30-mg doses of lansoprazole or 10-mg doses of rabeprazole during an 8-day course in a crossover manner. RESULTS: The relative values for the area under the serum concentration-time curve (AUC) of lansoprazole and rabeprazole in the hmEMs, htEMs, and PMs after the final doses were 1:1.7:3.9 and 1:1.7:3.8, respectively. The relative AUCs of gastrin in the hmEMs, htEMs, and PMs were 1.6:2.6:3.1 for lansoprazole and 1.6:2.6:2.9 for rabeprazole, respectively. CONCLUSION: The disposition kinetic behavior of the two PPIs is co-segregated with CYP2C19. The magnitude of CYP2C19-dependent drug availability in the systemic circulation and resulting gastrin response appears to be fairly similar between the two drugs within the same CYP2C19 genotypic groups after a multiple-dosing regimen.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2001

Effects of CYP2C19 genotypic differences in the metabolism of omeprazole and rabeprazole on intragastric pH.

BACKGROUND: Omeprazole is mainly metabolized in the liver by CYP2C19, a genetically determined enzyme, whereas rabeprazole is mainly reduced non-enzymatically and partially metabolized by CYP2C19. The therapeutic effects of rabeprazole are therefore assumed to be less affected by an individual's CYP2C19 status. AIM: To investigate the acid inhibitory effects and plasma levels of omeprazole and rabeprazole with reference to different CYP2C19 genotypes. METHODS: Fifteen healthy volunteers took a daily dose of 20 mg of omeprazole or rabeprazole for 8 days. On post-dose days 1 and 8, 24-h profiles of intragastric pH were recorded and plasma concentrations of omeprazole, rabeprazole and their metabolites were determined. RESULTS: After single and repeated doses of omeprazole, the intragastric pH values and plasma concentrations of omeprazole and its metabolites were significantly dependent on the CYP2C19 genotype. Significant differences in the same kinetic and dynamic parameters were also observed after single doses of rabeprazole. Although the plasma levels of rabeprazole differed among the different CYP2C19 genotype groups after repeated doses, no significant differences in intragastric pH values were observed. CONCLUSIONS: The acid inhibitory effects of omeprazole and rabeprazole are significantly dependent on the CYP2C19 genotype status, as well as on their intrinsic pharmacokinetic and pharmacodynamic characteristics and dosing schemes.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2000

Preparation and evaluation of w/o/w type emulsions containing vancomycin.

The objective of this contribution is to summarize the preparation and application of water-in-oil-in-water type multiple emulsions (w/o/w emulsions) entrapping vancomycin (VCM). Formulations of the emulsions (the composition of an oily phase or the type and concentrations of surfactants) and emulsification methods (a stirring method and a membrane method) or conditions (rotation rates, pore sizes of membrane or operation pressures) were evaluated in order to prepare stable w/o/w emulsions. The pharmaceutical properties of the w/o/w emulsions - particle sizes, viscosity, phase separation and drug entrapment efficiency were measured and evaluated. We prepared stable w/o/w emulsions with a particle size of about 3 micrometer and an entrapment efficiency of VCM of about 70%. When this emulsion was administered intravenously to rats, plasma concentrations of VCM were prolonged compared to the VCM solution alone. The results of this study show the potential of the w/o/w emulsions for several clinical applications as one of the drug delivery systems.

Animals↗
PubMed2000

Elevated levels of eotaxin and interleukin-5 in blister fluid of bullous pemphigoid: correlation with tissue eosinophilia.

BACKGROUND: Bullous pemphigoid (BP) often provokes blood and tissue eosinophilia, which suggests that some chemoattractants modulate the eosinophil infiltration in BP. Eotaxin, a CC chemokine, strongly attracts eosinophils, and interleukin (IL)-5 induces eosinophil differentiation, proliferation and colony formation in vitro. OBJECTIVES: To examine the correlation between levels of eotaxin and IL-5 and the number of lesional eosinophils, and the expression of eotaxin in BP lesions. PATIENTS/METHODS: In this study we measured eotaxin and IL-5 levels in blister fluid of BP by enzyme-linked immunosorbent assay. We also examined the expression of eotaxin in BP lesions by immunohistochemistry. RESULTS: Both eotaxin and IL-5 were detected at high levels in BP blister fluid. Blister fluid eotaxin, but not IL-5 levels, correlated significantly with the number of dermal infiltrating eosinophils. By immunohistochemistry, eotaxin was strongly expressed in epidermal keratinocytes around BP blisters. CONCLUSIONS: These findings suggest that eotaxin and IL-5 are strongly associated with the tissue eosinophilia of BP. Therapies which aim to inhibit production of eotaxin and IL-5 may improve the inflammation and blister formation in BP.

Adult↗
PubMed1999

Expression of tetraspans transmembrane family in the epithelium of the gastrointestinal tract.

Tetraspans transmembrane family (TSTF) members, also known as tetraspanin superfamily, have various effects on cell proliferation, motility, and adhesion not only in hematopoietic cells, but also in other type of cells. However, little is known about their expression in the human gastrointestinal (GI) tract. The authors characterized immunohistologically the localization of six members of TSTF (CD9, CD37, CD53, CD63, CD81, and CD82) in the normal epithelium from esophagus to colon. CD9 and CD82 molecules were strongly expressed in all epithelial surface membranes, from esophagus to colon, and their staining pattern was quite similar. Expression of CD37 was not detectable throughout the GI tract. Expression of CD53 was barely detectable. Expression of CD63 was clearly detected distal to the stomach, including the duodenum, small intestine, and colon. On the contrary, expression of CD81 was detected only in the esophagus--confined to a few layers from the basal layer. From these data it seems likely that the expression of TSTF molecules might be regulated differentially depending on the site of the GI tract.

Adult↗
PubMed1998

Fibromyxoma of the skin.

A patient presented with a solitary large subcutaneous tumor homogeneously composed of loose fibroblasts interspersed with abundant mucinous material. The literature was reviewed, and the origin, pathogenesis and clinical course of this rare neoplasm were briefly discussed.

Adjuvants, Immunologic↗
PubMed1998

Ulcerative porokeratosis.

A 54-year-old man presented with multiple annular plaques since infancy. During the intake of nifedipine and nitroglycerin over a period of 6 years, reddish, eruptive and ulcerative changes were seen in the pre-existing skin lesions on the penis, scrotum and legs. In addition to a typical cornoid lamella, histological examination revealed a band-like infiltration beneath the epidermis, liquefaction degeneration of the basal cell layer and subsequent coagulative necrosis of the keratinocytes. We review similar ulcerative types of porokeratosis in the literature and discuss the significance of our unusual case.

Histocytochemistry↗
PubMed1998

Atrophic dermatofibrosarcoma protuberans: a case report and review of the literature.

Dermatofibrosarcoma protuberans is not a difficult tumor to recognize because of its characteristic clinical appearance, although some unusual variants have been reported. We describe the atrophic variant of dermatofibrosarcoma protuberans in a 21-year-old female. The lesion was a smooth-surfaced, oval depression on the left subclavicular area, with a violaceous plaque at the center. The suspected clinical diagnosis did not include fibrous tumors, although histological examination showed the typical picture of dermatofibrosarcoma protuberans. Positive CD34 staining was also helpful in the diagnosis. We review 14 cases of the atrophic variant of dermatofibrosarcoma protuberans in the literature. Dermatologists should be aware of this uncommon but characteristic appearance of atrophic dermatofibrosarcoma protuberans.

Adolescent↗
PubMed1997

Dysregulated expression of transforming growth factor beta and its type-I and type-II receptors in basal-cell carcinoma.

In mammals, transforming growth factor-beta (TGF-beta) is found in 3 highly homologous isoforms that exert their effects via heteromeric complexes of type-I and type-II receptors (TbetaR-I and TbetaR-II). TGF-beta regulates the growth and metabolism of various cell types, including keratinocytes. We have investigated the immunohistological localization of TGF-beta1, TGF-beta2, TbetaR-I and TbetaR-II in normal human skin, basal-cell carcinoma (BCC), Bowen's disease, seborrheic keratosis, eccrine poroma and eccrine spiradenoma using frozen tissue specimens. In normal human skin, the immunoreactive TGF-beta2, but not TGF-beta1, was detected predominantly in the epidermis, follicles and sebaceous glands. The epidermal expression of TbetaR-I and TbetaR-II was very weak in the majority of normal skins. In BCC, TGF-beta2 expression was markedly reduced or completely negative. In addition, TbetaR-I- and TbetaR-II-positive stromal cells were accumulated in the fibrotic stroma in some BCCs. These stromal cells were partly but moderately positive for TGF-beta1. Decreased expression of TGF-beta2 was likely to be associated with the differentiation state of BCC cells, since TGF-beta2 expression was clearly observed in the squamoid foci of BCC. In addition, no expression of TGF-beta2 was detected in the eccrine secretory portion or in eccrine spiradenoma, but it was detected in the upper eccrine ducts and in eccrine poroma.

Acrospiroma↗
PubMed1997

[Seasonal changes of laboratory data in patients with Japanese cedar pollinosis].

Japanese cedar pollen (JCP) causes a significant seasonal allergic rhinitis in Japan during the early spring. Blood samples were collected monthly from October 1993 through October 1994 from 11 patients with Japanese cedar pollinosis. The patients were segregated into two categories based on specific IgE (RAST): single positive RAST to JCP only and multiple positive RAST to JCP, house dust (H1) and mite (D1). These two populations differed in levels of total serum IgE, numbers of eosinophils, basophils and neutrophils in peripheral blood and clinical symptoms. Seasonal increase of JCP-specific IgE was observed after pollen season in both groups. In the single positive group, but not in the multiple positive group, seasonal increase of the number of eosinophils in peripheral blood was observed with post seasonal fall and the level of total serum IgE was increased in the same manner as that of the JCP specific IgE. Although it was not significant, there was a broad seasonal increase of serum nitrate anion, a metabolite of nitric oxide.

Adult↗