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Biomedical subjects

Zenro Ikezawa

Publications and source records attributed to Zenro Ikezawa.

At least 19 recordsLinked to original sources

Effects of tributyltin on the development of atopic dermatitis-like eruptions in DS-Nh mice.

BACKGROUND: In the last few decades, numerous chemical compounds have been produced as a result of industrial development. At the same time, the number of atopic dermatitis (AD) patients has been increasing. It has been reported that tributyltin (TBT) compounds have effects not only on the reproductive system but also on the immune system. OBJECTIVE: To investigate whether TBT has an effect on AD, we fed a diet containing TBT to DS-Nh mice, which spontaneously developed dermatitis under conventional conditions. METHODS: DS-Nh mice fed TBT or a control diet were examined for skin changes, number of Staphylococcus aureus on the skin and serum IgE levels. To determine Th1/Th2 cytokine production by lymphocytes, lymphocytes of DS-Nh mice fed TBT and of controls were cultured with staphylococcal enterotoxin B and cytokine levels in the supernatants were measured by ELISA. We observed not only spontaneous dermatitis but also dermatitis induced by sensitization with 2,4,6-trinitrochlorobenzene (TNCB). RESULTS AND CONCLUSION: The AD-like lesions induced by TNCB sensitization were more severe in the mice fed TBT than in those fed the control diet. A greater increase in S. aureus on the skin was observed in the mice fed TBT than in the mice fed the control diet. A decrease in IFN-gamma production and an increase in IL-5 and IL-13 production were observed in the mice fed the TBT diet and treated with TNCB. These findings suggest that the increase in S. aureus and the enhancement of Th2 response induced by TBT exacerbate the AD-like lesions in mice treated with TNCB.

Animals↗

Effects of photocatalytic agent on DS-Nh mice, developing atopic dermatitis-like eruption with an increase of Staphylococcus aureus.

BACKGROUND: Staphylococcus aureus(S. aureus) is thought to play a significant role in the exacerbation of atopic dermatitis (AD). DS-Nh mice, a non-hair-bearing mouse model of AD, spontaneously develop dermatitis under conventional conditions. A remarkable increase in S. aureus is considered to strongly relate to the induction and aggravation of this dermatitis. A topical use of anatase-type titanium dioxide (TiO2) followed by UV irradiation, acting as photocatalyst, is believed to have antibacterial activity. We investigated the bactericidal effect of TiO2 with UV irradiation on DS-Nh mice to prevent the aggravation of the dermatitis. METHODS: Ten-week-old DS-Nh mice were treated with TiO2 in petrolatum on the back, followed by UVA irradiation, for 11 weeks. The severity of dermatitis was assessed by evaluating individual lesions using a 4-grade scale and expressed as the total skin score. S. aureus colonizing the mouse skin was counted after isolation and incubation with agar medium. The skin barrier dysfunction was evaluated by measuring transepidermal water loss (TEWL). RESULTS: The mice treated with TiO2 and UV irradiation showed a significant increase in total skin scores, the number of S. aureus and TEWL values, compared with non-treated mice. In contrast, these parameters were significantly lower in the mice treated with petrolatum and UV irradiation. CONCLUSIONS: A significant increase in S. aureus was recognized on the skin together with the aggravation of AD-like dermatitis in our mice model. Skin barrier dysfunction induced by TiO2 and UV irradiation seems to facilitate the increase in S. aureus.

Animals↗

A case of cutaneous T cell pseudolymphoma in a patient with Helicobacter pylori infection.

Cutaneous pseudolymphomas (CPL) are benign cutaneous lymphoproliferative infiltrations of various origin, including among others bacterial infections, viral infections and drugs . Helicobacter pylori has been frequently founded in the stomach of patients with MALT lymphoma. In January 2001, a 43-year-old man was referred to our department because of a 1-month history of itchy erythematous patches, plaques and flat tumors on his body. Histological examination revealed nodular infiltrations composed of lymphocytes, plasma cells and histiocytes with exocytosis of lymphocytes within the epidermis. Molecular analysis of rearrangement of T cell receptor and immunoglobulin heavy-chain genes did not reveal monoclonality. Based on these clinical, laboratory and histopathological data, a diagnosis of cutaneous T cell pseudolymphoma (CTPL) was made. The patient was anti-H. pylori antibody-positive, and was treated with anti-H. pylori combination with the result that all of the tumors had disappeared by January 2002. The patient has maintained complete response up to the last follow-up visit in December 2005.

Adult↗

Multiple chemical sensitivities following intolerance to azo dye in sweets in a 5-year-old girl.

BACKGROUND: Cases of multiple chemical sensitivities (MCS) have been reported predominantly in adult patients, but pediatric cases have rarely been reported. METHODS: We present a 5-year-old girl who suffered from recurrent reactions accompanied by urticaria, angioedema, headaches, dyspnea, loss of consciousness, and abdominal pain that were not eradicated, but were instead exacerbated, by various treatments with antihistamines and intravenous corticosteroids. Her diet diary revealed that symptoms occurred after ingestion of colorful sweets such as candies and jellybeans. Open challenge tests with food additives and nonsteroidal anti-inflammatory drugs (NSAIDs) were performed after elimination of these items. Skin prick tests using additives and NSAIDs, which were dissolved in saline, and prick- prick tests using candies and jellybeans, were carried out. RESULTS: Open challenge tests with Tartrazine, aspirin and acetaminophen were positive, whereas skin prick tests using additives and NSAIDs and prick-prick tests using candies and jellybeans were all negative. Consequently, intolerance to azo dyes and NSAIDs such as aspirin was diagnosed. However, she appeared to react to multiple chemical odors such as those of cigarette smoke, disinfectant, detergent, cleaning compounds, perfume, and hairdressing, all while avoiding additives and NSAIDs. On the basis of her history and the neuro-ophthalmological abnormalities, a diagnosis of severe MCS was made and she was prescribed multiple vitamins and glutathione. CONCLUSIONS: The present results suggest that in pediatric MCS, food and drug additives containing azo dyes might play important roles as elicitors.

Azo Compounds↗

[Oral allergy syndrome due to cashew nuts in the patient without pollinosis].

A 26-year-old woman felt tingling on her tongue and itching both in the throat and on the face immediately after she put a cashew nut on her tongue. She had a history of atopic dermatitis and bronchial asthma, but not of pollinosis. CAP-FEIA and skin prick test (SPT) were positive for cashew nuts. The results showed negative for peanuts and other tree nuts than cashew nuts. Consequently, she was diagnosed with oral allergy syndrome due to cashew nuts. In addition, the result of skin prick test with cashew nuts normalized one year after she began avoiding cashew nuts, indicating that cashew nuts allergy would be due to sensitization by itself rather than to cross-reactivity between cashew nuts and pollens in this case.

Adult↗

[Immedeate and delayed-type reactivity to fungi and effects of antifungal drugs on atopic dermatitis].

OBJECTIVE: To investigate immediate and delayed-type reactivity for fungi in atopic dermatitis (AD) patients and the effect of antifungal therapy. METHODS: We examined immediate and delayed-type reactivity in AD patients for Candida albicans and Malassezia furfur by skin prick test (SPT), and estimated the effect of amphotericin B (AMPH) and itraconazole (ITCZ). RESULTS: Twenty eight of 40 patients showed positive immediate-type reaction and 10 of 27 patients did delayed-type reaction for Candida albicans. As for Malassezia furfur, positive immediate-type reaction was shown in 30 of 40 patients and positive delayed-type reaction did in 4 of 27 patients. The RAST score of specific IgE to Candida albicans was low in the patients with positive delayed-type skin reaction for Candida albicans, while the score was high in the patients with the negative delayed-type skin reaction. Both of AMPH and ITCZ were effective to the patients with positive immediate-type reaction for Candida albicans in SPT. The skin reaction for Malassezia furfur was stronger in the patients treated with ITCZ effectively than in the patients treated not effectively. In addition, ITCZ was effective in all patients except one, who showed positive reaction for Malassezia furfur accompanied with negative reaction for Candida albicans in SPT. CONCLUSION: Fungal allergy is one of the aggravation factors of AD, and SPT is useful to evaluate fungal allergy and to choose effective antifungal therapy.

Adult↗

[Enhancement of nonsteroidal, anti-inflammatory drugs and preventive effect of antihistamines and disodium cromoglycate on wheat allergy].

BACKGROUND: Aspirin has been known to be an enhancer to wheat allergy, including wheat-dependent, exercise-induced anaphylaxis. OBJECTIVE: To investigate whether nonsteroidal, anti-inflammatory drugs (NSAIDs) other than aspirin would enhance allergic reactions after wheat ingestion and whether antihistamines and disodium cromoglycate would prevent these reactions. METHODS: Seven cases, whose reactions after wheat ingestion were enhanced by aspirin on challenge tests, were enrolled. Skin prick tests (SPT) and CAP-RAST were undergone for wheat and gluten. We used challenge tests of wheat after pretreatment of NSAIDs and preventive drugs. RESULTS: Four cases were diagnosed with wheat allergy, 3 cases had wheat-dependent, salicylic acid-induced anaphylaxis. SPT and CAP-RAST were positive for wheat and gluten in 5 of 7 cases and 4 of 7 cases, respectively. Dicrofenac enhanced the allergic reactions after wheat ingestion in 1 of 2 cases, whereas etodolac failed to enhance the symptoms in all 5 cases performed. Furthermore, disodium cromoglycate could not completely prevent the allergic reaction in all 4 cases and even enhanced the reaction in 1 case of them. To see an inhibitory effect of antihistamines on the symptoms, fexofenadine (in 2, 1 and 1 case, respectively), olopatadine, and chlorpheniramine were administrated before the challenge test, and as a result these drugs were found to have inhibitory effects on the allergic reaction. CONCLUSION: In this study, it was suggested that etodolac might be a relatively safe anti-inflammatory drug on wheat allergy and antihistamines could prevent allergic reactions more than DSCG in patients with wheat allergy.

Adult↗

[Trial of isolation of sick house syndrome and unclassified multiple chemical sensitivities--Definition of sick house syndrome, and symptoms].

PURPOSE: This study was designed to clarify the definition of sick house syndrome (SHS). METHODS: SHS was defined based on the disease related to habitation as follows. 1. The cause of the onset of a disease relates to house. 2. Symptoms appear within house. 3. Symptoms will be less serious or disappear if patient away from house. 4. If patient goes into house, symptoms will appear repeatedly. When it corresponded to all above, it was defined to SHS, and it classified as MCS (multiple chemical sensitivities) without above conditions. Even if SHS is isolated from similar disease completely, characteristic symptoms of MCS are hard to be detected because MCS are combination of two or more diseases. Based on this working hypothesis, the logistic regression by setting MCS as reference was performed so that characteristic symptoms of SHS show odds ratios with exceeding one. RESULTS: The odds ratios with more than two of characteristic symptoms in SHS were "nausea or vomiting" "Troublesome in everything" and the causative substances to which symptoms get worse was "The smell of a perfume and cosmetics". Characteristic symptoms of an allergy disease were detected by comparison with the allergic conjunctivitis, allergic rhinitis, and bronchial asthma, respectively. CONCLUSION: These results showed that the classification method was appropriate. This definition is not fundamentally differed from the definition of the sick-building syndrome of WHO.

Air Pollution, Indoor↗

Extramammary Paget's disease: analysis of growth signal pathway from the human epidermal growth factor receptor 2 protein.

Paget's disease is a skin cancer characterized by characteristic (Paget) cells scattered in the epidermis. Although its prognosis is generally favorable with surgical resection, the clinical outcome turns unfavorable in cases with recurrence and metastasis. Therefore, establishment of effective therapeutic regimens is required for advanced Paget's disease. The human epidermal growth factor receptor 2 (HER2) protein, a transmembrane growth factor receptor, is frequently overexpressed in malignancies, causing activation of the phosphatidylinositol 3 kinase (PI3K) and extracellular signal-regulated kinase (ERK) signal pathways. Recently, HER2-targeting molecular therapy using trastuzumab (Herceptin; Genentech, Inc, South San Francisco, Calif) was revealed to be effective in advanced breast cancers overexpressing HER2 protein. Here, we analyzed the correlation between activation of the HER2 signal pathways and clinicopathologic parameters of 36 extramammary Paget's disease samples from 34 Japanese patients, using immunohistochemical analyses for HER2, phosphorylated HER2, phosphorylated AKT, and phosphorylated ERK proteins. We found overexpression of the HER2 protein in 19.4% (7) of the lesions, 3 of which showed HER2 amplification by chromogenic in situ hybridization. Phosphorylated HER2 protein was detected in 12 lesions (33.3%), including 2 of the 7 HER2-overexpressing lesions. Phosphorylated AKT was detected in approximately 75.0% (27/36) and phosphorylated ERK in 38.9% (14/36). Both HER2 and AKT were simultaneously phosphorylated in 9 cases (25.0%) and HER2 and ERK in 9 cases (25.0%), but all 3 molecules were phosphorylated in only 1 sample. Phosphorylated ERK correlated with the maximum diameter of the tumors (P < .025), but other immunohistochemical parameters failed to show any correlation with clinicopathologic features. These results suggest the contribution of the HER2 signaling pathway to the pathogenesis and progression of some cases of extramammary Paget's disease, for which clinical use of molecular target therapy against the HER2 pathway is warranted.

Aged↗

Association of the IL12RB1 promoter polymorphisms with increased risk of atopic dermatitis and other allergic phenotypes.

Atopic dermatitis (AD) is frequently associated with eosinophilia, highly elevated immunoglobulin E (IgE) levels and increased levels of T-helper 2-type (Th2) cytokines in skin lesions due to infiltrating T cells. Interleukin-12 (IL-12), in combination with interferon-gamma (IFN-gamma), inhibits IgE synthesis and Th2 cell function. As the IFN-gamma-inducing cytokines IL-12 and IL-23 utilize IL-12Rbeta1 as part of their receptors, it is possible that polymorphic variants of the IL-12Rbeta1 (IL12RB1) gene might determine an individual's susceptibility to AD. Here, we carried out a systemic search for genetic variants of the human IL12RB1 in Japanese subjects and identified 48 genetic variants. In a case-control association study, we found that promoter polymorphisms -111A/T and -2C/T were significantly associated with an increased risk of AD under a recessive model. The -111T-allele frequency in the independent population of child asthmatics was also much higher than that in the control group. In addition, the -111T/T genotype was progressively more common in AD with high total serum IgE levels in an IgE-level-dependent manner. Deletion analysis of the IL12RB1 promoter suggested that the -265 to -104 region that contained the -111A/T polymorphic site harbored an important regulatory element. Furthermore, we showed that the -111A/T substitution appeared to cause decreased gene transcriptional activity such that cells from -111A/A individuals exhibited higher IL12RB1 mRNA levels than those from -111T allele carriers. Our results suggested that in individuals with the -111T/T genotype, reduced IL-12Rbeta1 expression may lead to increased Th2 cytokine production in the skin and contribute to the development of AD and other subsequent allergic diseases.

Adolescent↗

Functional SNPs in the distal promoter of the ST2 gene are associated with atopic dermatitis.

Atopic dermatitis (AD) is a common inflammatory skin disease associated with the local infiltration of T helper type 2 (Th2) cells. The ST2 gene encodes both membrane-bound ST2L and soluble ST2 (sST2) proteins by alternative splicing. The orphan receptor ST2L is functionally indispensable for Th2 cells. We found a significant genetic association between AD and the -26999G/A single nucleotide polymorphism (SNP) (chi2-test, raw P-value=0.000007, odds ratio 1.86) in the distal promoter region of the ST2 gene (chromosome 2q12) in a study of 452 AD patients and 636 healthy controls. The -26999A allele common among AD patients positively regulates the transcriptional activity of the ST2 gene. In addition, having at least one -26999A allele correlated with high sST2 concentrations and high total IgE levels in the sera from AD patients. Thus, the -26999A allele is correlated with an increased risk for AD. We also found that the -26999G/A SNP predominantly affected the transcriptional activity of hematopoietic cells. Immunohistochemical staining of a skin biopsy specimen from an AD patient in the acute stage showed ST2 staining in the keratinocytes as well as in the infiltrating cells in the dermal layer. Our data show that functional SNPs in the ST2 distal promoter region regulate ST2 expression which induces preferential activation of the Th2 response. Our findings will contribute to the evaluation of one of the genetic risk factors for AD.

Alleles↗

A novel method to control the balance of skin microflora. Part 1. Attack on biofilm of Staphylococcus aureus without antibiotics.

BACKGROUND: Staphylococcus aureus (SA) is usually present in atopic dry skin, and not only in regions seriously affected by atopic dermatitis. SA discharges various toxins and enzymes that injure the skin, and forms a biofilm from fibrin fiber and glycocalyx; the biofilm is important for adhesion of SA to the skin and for resistance to anti-microbial agents. Even highly effective moisturizers do not work perfectly on atopic dry skin. Staphylococcus epidermidis (SE) is a major constituent of skin microflora on healthy human skin, and provides protection against the growth of pathogenic bacteria. OBJECTIVES: Since treatment with anti-microbials may lead to re-growth of SA, which grows faster than other Staphylococci and often shows antibiotic resistance, we searched for novel approaches to control the skin-microfloral balance without using conventional anti-microbials. METHOD: Biofilm formation by SA in vitro was observed in detail using scanning electron microscopy. Approximately 500 substances were screened for a selective effect on SA growth and SA biofilm. RESULTS: We found that xylitol inhibited the formation of glycocalyx, and farnesol dissolved fibrin fibers. Farnesol suppressed the growth of only SA, and did not affect that of SE. Xylitol and farnesol synergistically inhibited biofilm formation by SA. CONCLUSION: Xylitol and farnesol have potential for controlling the skin-microfloral balance because of their selective effects and inhibition of biofilm formation. They might provide a useful and safe method to care for skin colonized by SA, without using antibiotics.

Administration, Cutaneous↗

Effects of TNCB sensitization in DS-Nh mice, serving as a model of atopic dermatitis, in comparison with NC/Nga mice.

BACKGROUND: It has been predicted that a type-1 and type-2 helper T cell (Th1/Th2) imbalance exists in atopic dermatitis (AD). In DS-Nh mice, an AD mouse model, Staphylococcus aureus increases on the skin surface. OBJECTIVE: To investigate whether the Th1-dominant response has an influence on the development of AD, we induced chronic allergic hypersensitivity with 2,4,6-trinitrochlorobenzene (TNCB ) in two AD mouse models: NC/Nga mice and DS-Nh mice. Th1 and Th2 cytokine production of splenocytes was assessed under stimulation with staphylococcal enterotoxin B (SEB) which induces a Th1 response in DS-Nh mice with or without TNCB sensitization. METHODS: We examined clinical skin changes, transepidermal water loss (TEWL), the number of S. aureus on the skin and the serum IgE levels in these mice treated repeatedly with TNCB under conventional conditions (free of fur mites). The splenocytes of DS-Nh mice were cultured with SEB and the cytokine levels in the supernatants were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: Significant skin changes were observed on the skin even where TNCB was not applied in both mice treated with TNCB. Increases in S. aureus on the skin and serum IgE levels were detected in DS-Nh mice, but not in NC/Nga mice. In DS-Nh mice, IFN-gamma and IL-13 production of splenocytes increased in the mice treated with TNCB. CONCLUSION: These results suggest that there might be a different mechanism of dermatitis induction between NC/Nga and DS-Nh mice. Th1 responses might play an important role in the development of dermatitis and increase in serum IgE levels in DS-Nh mice through an increase in IL-13 production.

Animals↗

Differential gene expression profile between cord blood progenitor-derived and adult progenitor-derived human mast cells.

In order to better understand the mechanisms governing the display of mast cell characteristics in human mast cells (MCs), such as cord blood (CB)-derived cultured mast cells, peripheral blood (PB)-derived cultured MCs, and differentiated adult-lung cultured MCs, we examined the transcriptomes of these three types MCs using oligonucleotide microarray (GeneChip) and hierarchical clustering analysis. The expression profile of CB-derived MCs substantially differed from those of PB- and lung-derived MCs. In CB-derived MCs, we identified 132 up-regulated transcripts, such as MARCKS, KRT1, TIMP2, SERPINA1, and TLR2, and 428 down-regulated transcripts, such as LTBP3, CDC42BPA, DDO, DICER1, and FCER1A. Moreover, using RT-PCR and FACS analysis, we confirmed the expression of TLR2, which plays an important role in innate immunity, in CB-derived MCs but not in PB-derived MCs. In addition, it was observed that CB-derived MCs uniquely release histamine and CCL1, which are produced by human MCs but not by human monocytes, in response to peptidoglycan (PGN), although it had been controversy issue whether CB-derived MCs could, in fact, induce degranulation in response to PGN. These results indicated that in innate immunity MCs derived from neonatal hemopoietic cells might have unique functions compared to their adult counterparts because of different gene profiles.

Adult↗

Drug-induced hypersensitivity syndrome due to cyanamide associated with multiple reactivation of human herpesviruses.

Drug-induced hypersensitivity syndrome (DIHS), characterized by serious adverse systemic reactions in addition to skin rash, has unknown pathogenesis. Its association with human herpesvirus (HHV), mainly HHV-6, has been reported recently. A 46-year-old Japanese man is described in whom a generalized eruption developed about 1 month after taking cyanamide, a drug for alcoholism. This was associated with the following manifestations: high fever, lymphadenopathy, facial edema, marked leukocytosis with eosinophilia and atypical lymphocytes, lymphocytopenia, liver and renal dysfunction, and low IgG level. He was treated with 8 mg betamethasone daily and his condition improved, but he needed low-dose corticosteroid for almost 1 year because of several episodes of recurrence. HHV-6, HHV-7, herpes simplex virus (HSV), and cytomegalovirus (CMV) specific IgG titers showed more than a four-fold rise sequentially. Significant numbers of copies of HHV-6 and HHV-7 DNA were detected in the peripheral white blood cells by real-time polymerase chain reaction (PCR). HHV-6 and CMV DNA were detected in the serum by nested PCR. A patch test for cyanamide was positive. The diagnosis of DIHS due to cyanamide, which has never been reported as a causal drug of DIHS, accompanied by reactivation of not only HHV-6, but also HHV-7, CMV, and HSV, was made. Disturbance of the immune system was suggested by the persistent low level of IgG, and consecutive viral reactivation may have participated in the prolonged course in this case.

Agammaglobulinemia↗

Cyclophosphamide decreases the number, percentage and the function of CD25+ CD4+ regulatory T cells, which suppress induction of contact hypersensitivity.

BACKGROUND: It is well known that cyclophosphamide (Cy) treatment before sensitization paradoxically enhances rather than suppresses contact hypersensitivity (CH) reactions. In fact, Cy-treated mice developed a significant (p < 0.05) increase of the CH reactions to 2,4,6-trinitro-1-chrolobenzene (TNCB) in comparison with untreated mice. OBJECTIVE: In order to examine whether the target cells of Cy in the immuno-augmentative effect are CD25(+) CD4(+) regulatory T cells or not, we investigated effect of Cy treatment on CD25(+) CD4(+) T cells. METHOD: We examined Cy-treated CD25(+) CD4(+) T cells by flow cytometer and by inhibition assay on proliferation of CD25(-) CD4(+) T cells. RESULTS: Cy treatment remarkably reduced the number and percentage of CD25(+) CD4(+) T cells in the spleen and lymph nodes 3 and 5 days later. Moreover, CD25(+) CD4(+) T cells taken from the Cy-treated mice 3 days later showed the lower suppressive activity on proliferation of CD25(-) CD4(+) T cells, as compared to that from the untreated mice. Furthermore, transfer of CD25(+) CD4(+) T cells from untreated mice resulted in a significant decrease (p < 0.05) of the CH reactions enhanced by Cy treatment. CONCLUSION: These results indicate that enhancement of the CH reactions to TNCB by Cy treatment is attributed to the decrease in the number, percentage and the function of CD25(+) CD4(+) regulatory T cells.

Animals↗