Search PubMed⌕ Search

Biomedical subjects

Takeshi Fukuda

Publications and source records attributed to Takeshi Fukuda.

53 records · Page 3Linked to original sources
PubMed2003

The antiallergic drug oxatomide promotes human eosinophil apoptosis and suppresses IL-5-induced eosinophil survival.

BACKGROUND: Eosinophils accumulated in sites of allergic inflammation are thought to play a crucial role in the pathogenesis of allergic disorders including asthma, allergic rhinitis, and atopic dermatitis, and tissue eosinophilia is attributable to increased eosinophil survival or decreased eosinophil apoptosis. OBJECTIVE: Effects of the antiallergic, histamine H1 blocker oxatomide on viability and apoptosis of eosinophils isolated from the peripheral blood of atopic subjects were studied. METHODS: Eosinophil viability and apoptosis were evaluated by using a colorimetric assay and annexin V-labeling, caspase-3 activity, and DNA fragmentation assay. RESULTS: The viability of eosinophils increased in the presence of IL-5 (10 ng/mL), confirming that IL-5 prolongs eosinophil survival in vitro. Application of oxatomide at concentrations over 20 micromol/L for 24 hours decreased the IL-5-induced enhancement of eosinophil viability. Double staining of the cells with annexin V and propidium iodide showed that deprivation of IL-5 promoted spontaneous eosinophil apoptosis and that oxatomide facilitated apoptosis and suppressed the prolongation of eosinophil survival stimulated by IL-5. In the absence of IL-5, approximately 71% and 96% of eosinophils after 24 and 48 hours, respectively, underwent spontaneous apoptosis. IL-5 decreased the rate of eosinophil apoptosis to 38% and 52% after 24 and 48 hours, respectively. Oxatomide increased eosinophil apoptosis in a concentration-dependent manner in the presence of IL-5. Furthermore, oxatomide increased caspase-3 activity and DNA fragmentation. CONCLUSION: We demonstrated that oxatomide possesses a novel therapeutic effect of apoptosis promotion on eosinophils and prevents the antiapoptotic effects of IL-5, suggesting that oxatomide may contribute to resolution of tissue eosinophilia in allergic inflammation.

Anti-Allergic Agents↗
PubMed2003

Polarized in vivo expression of IL-11 and IL-17 between acute and chronic skin lesions.

BACKGROUND: In atopic dermatitis (AD) there is evidence of tissue fibrosis involving a number of structural changes, including papillary dermal fibrosis and epidermal hyperplasia. These changes are suggested to be the result of chronic inflammation of the skin. Several remodeling-associated cytokines, including transforming growth factor (TGF) beta1, IL-11, and IL-17, have been shown to be increased in allergic diseases, including asthma. OBJECTIVE: We investigated TGF-beta1, IL-11, and IL-17 expression in skin biopsy specimens recovered from acute and chronic skin lesions from patients with AD, as well as from uninvolved skin of patients with AD and skin from healthy volunteers. We also examined the correlation between the expression of these cytokines and the extent of total, type I, and type III collagen deposition. METHODS: We evaluated the expression of TGF-beta1, IL-11, and IL-17 by means of immunohistochemistry. Collagen deposition was assessed by means of immunohistochemistry and van Gieson staining. RESULTS: TGF-beta1 expression was markedly enhanced in both acute and particularly chronic lesions (P <.001). Although IL-11 expression was significantly increased only in chronic lesions (P <.0001), IL-17 was preferentially associated with acute lesions (P <.005). Although collagen type III deposition was not significantly different among the groups, type I collagen deposition was significantly increased in chronic AD lesions (P <.0005). There was a significant correlation between IL-11 and type I collagen deposition, as well as the number of eosinophils in skin specimens from patients with AD (r (2) = 0.527, and r (2) = 0.622, respectively; P <.0001). CONCLUSION: These results suggest that TGF-beta1, IL-11, and IL-17 are involved in the remodeling of skin lesions in patients with AD. However, IL-11 and IL-17 are preferentially expressed at different stages of the disease. Type I collagen appeared to be the major subtype involved in this repair process.

Acute Disease↗
PubMed2003

[Effects of Bakumondo-to (Mai-Men-Dong-Tang) on cough sensitivity to capsaicin in asthmatic patients with cough hypersensitivity].

UNLABELLED: Some patients with bronchial asthma have increased cough sensitivity. In such patients coughing may be an inducer of wheeze. The aim of the present study was to investigate the effect of Bakumondo-to on the cough sensitivity and respiratory tract inflammation in asthmatic patients with increased cough sensitivity. In addition influences of intensity of respiratory tract inflammation, gender, type of asthma, and disease period on the effect of Bakumondo-to on the cough sensitivity were examined. Twenty-one bronchial asthmatics whose cough thresholds to capsaicin were less than 3.9 microM were examined. METHODS: Cough thresholds to capsaicin (concentration of inhaled capsaicin solution causing 5 or more coughs) was measured before and after 2 months or more treatment with Bakumondo-to (9 g/day, TJ-29). Number of eosinophils in peripheral blood, sputum eosinophil ratio, and ECP level in the serum were also measured before and after treatment. RESULTS: Bakumondo-to significantly increased the cough threshold. Although respiratory tract inflammation was not significantly improved, number of eosinophils in peripheral blood, sputum eosinophil ratio and ECP level in the serum were remarkably decreased more than the half. And Bakumondo-to was more effective in asthmatic subjects with severe airway inflammation. Furthermore, a greater effect of it was observed in women. A greater effect was also observed in patients having a disease duration of less than 1 year. CONCLUSION: Our results suggest that Bakumondo-to may be an effective therapeutic preparation for coughing in asthmatic patients with cough hypersensitivity.

Adolescent↗
PubMed2003

Efficacy and safety of rush immunotherapy in patients with Hymenoptera allergy in Japan.

In Japan, approximately 40 persons die annually from anaphylaxis caused by Hymenoptera stings. Venom immunotherapy is considered safe and effective for the treatment of allergic systemic reactions caused by Hymenoptera stings in patients with Hymenoptera allergy. We studied the efficacy and safety of rush immunotherapy in patients who had a history of systemic reactions to Hymenoptera stings in Japan. Between 1988 and 2002, 95 patients with a history of systemic reactions to Hymenoptera stings were investigated. The stings originated from honeybees in 5 patients, yellow jackets in 28, wasps in 48, both yellow jackets and wasps in 9, and both yellow jackets and honeybees in 5. All patients had venom-specific IgE antibodies in sera (RAST score > or = 2) and received rush immunotherapy with venom extracts at our hospital. Forty-three patients had 63 field re-stings during immunotherapy. Of these patients, 41 (95.3%) with 59 field re-stings (93.7%) had no systemic reactions. Two patients (4.7%) with four field restings (6.3%) had anaphylactic shock. Although anaphylactic reactions developed in two patients (2.1%) during rush immunotherapy with honeybee venom and one patient (1.1%) during maintenance therapy wasp venom, systemic adverse reactions were mitigated by treatment with antihistamines before venom injection. Our results show that immunotherapy is safe and effective for the prevention of systemic reactions to Hymenoptera re-stings in patients with Hymenoptera allergy. We therefore recommend that patients who are allergic to Hymenoptera venom prophylactically receive immunotherapy.

Adolescent↗
PubMed2003

[The indication and practice of home oxygen therapy].

COPD(Chronic Obstructive Pulmonary Disease) is a cause of chronic respiratory failure which leads to pulmonary hypertension and cor pulmonale. Not only chronic hypoxia but also low QOL(quality of life) due to dyspnea are shown to affect survival of COPD patients. HOT(Home Oxygen Therapy) is one of the most successful home therapy in Japan after the availability of health insurance in 1985. HOT is the only therapy to prolong life expectancy of COPD patients with chronic respiratory failure. The induction of HOT needs a consideration of risk of narcosis and evaluations of oxygen desaturation during exercise and sleep as well as hypoxia at rest. Higher QOL of HOT patients might require an alteration of prescription guidelines of HOT.

Chronic Disease↗
PubMed2002

Anti-interleukin-9 antibody treatment inhibits airway inflammation and hyperreactivity in mouse asthma model.

Numerous in vitro and in vivo studies in both animals and patients with asthma have shown that interleukin (IL)-9 is an important inflammatory mediator in asthma. To examine the effects of IL-9 antagonism on airway inflammation, ovalbumin-sensitized BALB/c mice were intravenously given anti-IL-9 antibody or an isotype-matched control antibody 30 minutes before challenge with aerosolized ovalbumin. Airway response to methacholine was measured, and samples of bronchoalveolar lavage fluid (BALF) were obtained 24 hours after the last antigen challenge. Lung tissue was harvested and examined histopathologically. After ovalbumin challenge, there were significant increases in airway hyperreactivity, the numbers of inflammatory cells in lung, and IL-4, IL-5, and IL-13 production in BALF. Treatment with anti-IL-9 antibody significantly prevented airway hyperreactivity in response to methacholine inhalation. Blockade of IL-9 reduced the numbers of eosinophils (0.3 +/- 0.1 x 10(5) and 23.6 +/- 0.5 x 10(5)/ml, anti-IL-9 antibody/control immunoglobulin G) and lymphocytes (0.2 +/- 0.2 x 10(5) and 0.8 +/- 0.1 x 10(5)/ml) in BALF. Anti-IL-9 antibody treatment also reduced the concentrations of IL-4 (from 70.6 +/- 4.6 to 30.8 +/- 5.2 pg/ml), IL-5 (from 106.4 +/- 12 to 54.4 +/- 6.6 pg/ml), and IL-13 (from 44.2 +/- 7.6 to 30.1 +/- 5.5 pg/ml) in BALF. Macrophage-derived cytokine expression in the airways was also decreased by IL-9 blockade. Taken together, our findings emphasize the importance of IL-9 in the pathogenesis of asthma and suggest that blockade of IL-9 may be a new therapeutic strategy for bronchial asthma.

Animals↗
PubMed2002

A putative silencer element in the IL-5 gene recognized by Bcl6.

The Bcl6 gene is ubiquitously expressed in adult murine tissues and its product functions as a sequence-specific transcriptional repressor. Bcl6-deficient mice displayed eosinophilic inflammation caused by overproduction of Th2 cytokines. The regulatory mechanism of those cytokine productions by Bcl6 is controversial. When CD4(+) T cells from Bcl6-deficient and lck-Bcl6-transgenic mice were stimulated with anti-CD3 Abs, production of IL-5 among Th2 type cytokines was preferentially affected by the amount of Bcl6 in the T cells. We found a putative Bcl6-binding sequence (IL5BS) on the 3' untranslated region in the murine and human IL-5 genes, and specific binding of Bcl6 protein to the sequence was confirmed by gel retardation assay and chromatin immunoprecipitation assay. The binding activity of endogenous Bcl6 was transiently diminished in Th2 but not in Th1 clones after anti-CD3 stimulation. The exogenous Bcl6 repressed expression of the reporter gene with the IL5BS in K562 cells and the repressor activity was lost by a point mutation of the IL5BS. Furthermore, the IL5BS was required for Bcl6 to repress expression of the IL-5 cDNA. Thus, the IL5BS may act as a silencer element for Bcl6 to repress expression of the IL-5 gene.

3T3 Cells↗
PubMed2002

Activation of TGF-beta/Smad2 signaling is associated with airway remodeling in asthma.

BACKGROUND: Transforming growth factor beta (TGF-beta) has been suggested to play an important role in the development of airway remodeling in asthma; this suggestion is based on evidence that expression levels of TGF-beta are correlated with unique parameters of airway remodeling, such as thickness of basement membrane. However, the relevant studies were inconclusive because they were unable to demonstrate active signaling mediated by the cytokine in the airways of asthmatic individuals. OBJECTIVE: We sought to determine whether TGF-beta signaling was active in the airways of asthmatic subjects and, if so, whether it was correlated with clinicopathologic features associated with the development of airway remodeling in asthma. METHODS: We examined the phosphorylation status of Smad2 in bronchial biopsy samples obtained from 40 asthmatic subjects as a marker of active TGF-beta signaling, and we studied its correlation with basement membrane thickness. RESULTS: Expression levels of phosphorylated Smad2 in bronchial biopsy specimens from asthmatic subjects were higher than those in specimens from normal subjects, and they were correlated with basement membrane thickness in asthma. CONCLUSION: The findings provide evidence that TGF-beta signaling was active in asthmatic airways and that the activity was associated with the development of airway remodeling in asthma.

Adult↗
PubMed2002

Expression of Smad7 in bronchial epithelial cells is inversely correlated to basement membrane thickness and airway hyperresponsiveness in patients with asthma.

BACKGROUND: Smad7 is an intracellular antagonist of transforming growth factor beta (TGF-beta) signaling, which could determine the intensity or duration of the TGF-beta signal. Because TGF-beta has been implicated in the development of airway remodeling in asthma on the basis of its strong capacity to induce extracellular matrix production, it is possible that Smad7 also plays some roles in the regulation of the process. OBJECTIVE: We sought to determine the relationships between Smad7 expression in bronchial biopsy samples from asthmatic subjects and clinicopathologic features. METHODS: Bronchial biopsy specimens were obtained from 40 asthmatic subjects and 6 healthy control subjects. Expression levels of Smad7 on a histologic section were estimated by immunohistochemical staining. In addition, the roles of Smad7 in TGF-beta-mediated transcriptional responses were studied by in vitro studies. RESULTS: Smad7 immunoreactivity was detected mainly in bronchial epithelial cells in control and asthmatic subjects. Interestingly, asthmatic subjects exhibited less Smad7 immunoreactivity in bronchial epithelial cells than normal subjects. Expression levels of Smad7 in bronchial epithelial cells were inversely correlated with basement membrane thickness and airway hyperresponsiveness in asthmatic subjects. In addition, abrogation of endogenous Smad7 expression through use of an antisense oligonucleotide enhanced transcriptional responses to TGF-beta, whereas overexpression of Smad7 inhibited TGF-beta-induced plasminogen activator inhibitor 1production in a human bronchial epithelial cell line, BEAS2B cells. CONCLUSION: These findings suggest that Smad7 is a key molecule that defines the susceptibility of bronchial epithelial cells to TGF-beta action and that regulation of Smad7 expression in bronchial epithelial cells might be related to the development of airway remodeling and airway hyperresponsiveness in asthma.

Adult↗
PubMed2002

Interaction of endogenous compounds in human and rat urine with P-glycoprotein.

The effect of hydrophobic extracts of human and rat urine on in-vitro P-glycoprotein (P-gp) function was examined, in terms of intra-, inter-individual variations, and physiological states. Six urine samples out of 7, obtained from one male subject on different days, suppressed P-gp function with different potencies. Similarly, 11 samples out of 15 different individuals (8 males and 7 females) inhibited P-gp function. Among them, urine from one female, obtained 1 month after delivery, showed a potent inhibitory effect. Another urine from a pregnant female, obtained 1 week before delivery, showed further potent inhibition on P-gp function. In addition, urine from normal rats strongly inhibited P-gp function at much lower concentrations than human urine, and the inhibitory potencies varied in diseased states; control (without urine extract)=experimental acute renal failure<experimental acute hepatic failure<normal rat urine. When human urine extract was separated by a two-dimensional thin-layer chromatography, several spot fractions inhibited P-gp function, and equilin was identified in one fraction as an endogenous P-gp inhibitor. In conclusion, it was demonstrated that urine contains many endogenous P-gp inhibitors, and their inhibitory potencies on P-gp function vary with intra- and inter-individual variations, and under different physiological states.

Journal Article↗
PubMed2002

[Tailor-made medicine for bronchial asthma].

Asthma is a complex genetic disorder with variable phenotype, largely attributed to the interactions on environment and multiple genes. Numerous asthma and atopy loci have been reported in studies demonstrating associations and/or linkage levels, and bronchial hyperresponsiveness to alleles of microsatellite markers and single nucleotide polymorphisms with in specific genes. Progress in the field of pharmacogenetics has revealed that the phenotypically different responses of patient to drugs are genetically determined by the polymorphisms in the genes encoding the drug target, such as 5-lipoxigenase and beta 2-adrenergic receptor. The information about polymorphisms, is accumulated, tailor-made medicine will be applicable to medical care of individual asthmatics.

1-Alkyl-2-acetylglycerophosphocholine Esterase↗
PubMedDate not supplied

Surface display of organophosphorus hydrolase on Saccharomyces cerevisiae.

The gene encoding organophosphorus hydrolase (OPH) from Flavobacterium species was expressed on the cell surface of Saccharomyces cerevisiae MT8-1 using a glycosylphosphatidylinositol (GPI) anchor linked to the C-terminal region of OPH. Immunofluorescence microscopy confirmed the localization of OPH on the cell surface, and fluorescence intensity measurement of cells revealed that 1.4 x 10(4) molecules of OPH per cell were displayed. Seventy percent of OPH whole-cell activity was detected on the cell surface by protease accessibility assay. The activity of OPH was highly dependent on cell growth conditions. The maximum activity was obtained when cells were grown in a synthetic dextrose medium lacking tryptophan (SD-W) buffered by 2-[4-(2-hydroxyethyl)-1-piperazinyl]ethanesulfonic acid (HEPES, 200 mM, pH 7.0) at 20 degrees C, and cobalt chloride was added at 0.1 mM. S. cerevisiae MT8-1 displaying OPH which exhibited a higher activity than Escherichia coli displaying OPH using the ice nucleation protein (INP) anchor. The use of S. cerevisiae MT8-1, which has a "generally regarded as safe (GRAS)" status, as a host for the easy expression of the OPH gene provides a new biocatalyst useful for simultaneous detoxification and detection of organophosphorus pesticides.

Aryldialkylphosphatase↗
PubMedDate not supplied

Construction of a cultivation system of a yeast single cell in a cell chip microchamber.

A novel single cell screening system was constructed using a yeast cell chip in combination with the yeast cell surface engineering [NanoBiotechnology 2005, 1, 105-111]. Enzymes or functional proteins displayed on a yeast cell surface can be used as a protein cluster. To achieve high-throughput screening of protein libraries on the cell surface, a catalytic reaction by a single cell-surface-engineered yeast cell was successfully carried out in the microchamber on the yeast cell chip. After screening, to replicate a target cell for use in measuring of activity, DNA sequencing, and preservation, a novel single cell cultivation system in the yeast cell chip was constructed. To avoid damage of the rapid dry up of medium in the microchamber array, the yeast cell chip was modified with a protection sheet, so that the modified chip was like a micro-culture tank constructed on the yeast cell chip microchamber. As a result, single yeast cell cultivation in the yeast cell chip microchamber was observed, and the modified yeast cell chip was evaluated to be good for a single cell selection. The improvement showed that the single cell screening system coupled with the single cell cultivation using the modified yeast cell chip may be superior to that by a cell sorter for the isolation of a target cell and its practical use.

Cell Count↗
PubMedDate not supplied

Enhancement of cellulase activity by clones selected from the combinatorial library of the cellulose-binding domain by cell surface engineering.

To improve the cellulolytic activity of a yeast strain displaying endoglucanase IotaIota (EG II) from Trichoderma reesei, a combinatorial library of the cellulose-binding domain (CBD) of EG II was constructed by using cell surface engineering. When EG II degrades celluloses, CBD binds to cellulose, and its catalytic domain cleaves the glycosidic bonds of cellulose. CBD had a flat face, composed of five amino acids for binding. It was supposed that the three hydrophobic amino acid residues of the five amino acid residues were essential for binding to cellulose. Therefore, by improving the two remaining amino acid residues, construction of mutants with a combinatorial library of the two amino acids in CBD was carried out and binding ability and hydrolysis activity were measured. In the first screening by halo assay using the Congo Red staining method, about 200 of the 2000 colonies formed clear halos, and then five colonies with the clearest halos were finally selected. In the second screening, the binding ability of the five mutants to phosphoric acid-swollen Avicel was measured. In addition, the measurement of hydrolysis activity toward carboxymethylcellulose (CMC) using the screened mutants was carried out. As a result, the mutated EG II exhibiting higher binding ability (1.5-fold) had higher hydrolysis activity (1.3-fold) compared to the parent EG II-displaying yeast cell, demonstrating that CBD has confirmatively some effect on the cellulase activity through its binding ability of the enzyme to cellulose.

Binding Sites↗