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Biomedical subjects

T Tezuka

Publications and source records attributed to T Tezuka.

At least 91 records · Page 5Linked to original sources
PubMed1996

Role of staphylococcal enterotoxins in pathogenesis of atopic dermatitis: growth and expression of T cell receptor V beta of peripheral blood mononuclear cells stimulated by enterotoxins A and B.

In order to investigate the role of staphylococcal enterotoxins in the pathogenesis of dermatitis in atopic patients, the growth and expression of T cell receptor V beta in peripheral blood mononuclear cells (PBMCs) from atopic dermatitis patients induced by stimulation with staphylococcal enterotoxin A (SEA) or staphylococcal enterotoxin B (SEB) were examined. Lymphocyte stimulation tests (LST) using SEA or SEB were performed in atopic dermatitis (AD) patients (n = 10) and normal controls (n = 5). PBMCs from AD patients displayed significantly stronger responses to SEA or SEB than those from the controls. To ascertain further whether SEA acts as a superantigen in atopic dermatitis, the expression of 22 genes in the variable region of the beta chain (V beta) of T cell receptors (TcR) was examined before and after stimulation with SEA by a reverse transcriptase-polymerase chain reaction (RT-PCR). Before stimulation, only weak expression of V beta was observed, and the expression of the various V beta segments was uniform in the normal controls (n = 3). In the AD patients (n = 3), the expression of V beta was enhanced, but was not uniform in 2 out of 3 patients and the pattern of expression was characteristic in each individual. This suggests that V beta expression varies in individual AD patients and displays restricted heterogeneity, reflecting the diversity of the etiology of the disease. After culture of the SEA-stimulated cells, no difference was observed in the expression of TcR V beta segments in the 3 normal controls as compared with that prior to stimulation, but particular V beta segments were intensely expressed in 3 AD patients, displaying distinct patterns (case I: V beta 9, V beta 10, V beta 18; case 2: V beta 6.1-3; case 3: V beta 6.1-3, V beta 18). Many of these V beta segments corresponded with those known to be induced by SEA. These results suggest oligoclonal proliferation of T cells in the peripheral blood of AD patients and high responsiveness in each clone, and since the expression of V beta segment after SEA stimulation was restricted, the actions of staphylococcal enterotoxins as superantigens were suggested.

Adolescent↗
PubMed1996

Transforming growth factor-alpha induces interleukin-6 in the human keratinocyte cell line HaCaT mainly by transcriptional activation.

There is ample evidence that several cytokines, including transforming growth factor-alpha (TGF-alpha), interleukin (IL)-6, and IL-8 are upregulated in psoriasis, suggesting a pathogenic role for these cytokines. The sequence of these events, however, has not been elucidated. Recently it has been reported that TGF-alpha induces IL-6 in thymocytes through posttranscriptional regulation; therefore, we were interested in whether TGF-alpha can also induce IL-6 in human keratinocytes. Thus, we stimulated the human keratinocyte cell line HaCaT with TGF-alpha and tested supernatants for IL-6 activity. TGF-alpha resulted in a significant induction of the release of IL-6. This was also confirmed by northern blot analysis, which revealed a transient increase in IL-6 mRNA. This increase was unlikely due to enhanced mRNA stability, because we could not observe induction of IL-6 -specific transcripts by TGF-alpha in the presence of actinomycin D. To determine whether IL-6 induction by TGF-alpha is transcriptionally regulated, we transfected fragments of the IL-6 upstream region, subcloned into a plasmid just upstream of the chloramphenicol acetyl transferase coding region, into HaCaT cells. A 238-bp fragment and a 123-bp fragment, both containing nuclear factor (NF)-IL-6 and NFkappaB sites, exhibited significant induction of chloramphenicol acetyl transferase activity upon treatment with TGF-alpha. Because IL-6 transcription is known to be regulated by activation of NFkappaB and NF-IL-6, we analyzed the activation of these DNA-binding proteins by electrophoretic mobility shift assays. NF-IL-6 binding to a 32P-labeled NF-IL-6 binding sequence was enhanced 20 min after TGF-alpha stimulation and returned to basal levels within 90 min, whereas NFkappaB binding activity was enhanced after 20 min and returned to normal 60 min after stimulation. We conclude that TGF-alpha induces IL-6 in HaCaT cells and, in contrast to thymocytes, may do so by transcriptional activation, possibly through activation of NFkappaB and NF-IL-6.

Base Sequence↗
PubMed1996

[Detection of chlamydial antibodies by immunoblotting technique--in comparison of three commercially available test kits and micro-IF].

We reexamined the assay conditions of immunoblotting (W-B) technique to detect antibodies (IgG and IgA) to C. trachomatis serovar L2. Partially purified Chlamydia (35% urografin) was used as the antigen. The marker bands of W-B for positive and/or negative are major outer membrane protein (MOMP) band and either one or more bands staining in 40-62 KDa area. We then compared the sensitivity and specificity of three commercially available test kits and micro-IF by using W-B as a standard. The kits compared were sero-IPALISA-IgG-IgA, IP-Azyme-IgG-IgA and HITAZYME-IgG-IgA, and micro-IF. Serum samples were collected from the outpatient departments of gynecology, urology, and internal medicine and pediatrics. The results of agreement between W-B and test kits in IgG detection were as follows: in sero-IPALISA, total agreement was 85.7%, positive agreement 83.3%, negative agreement 90.9% and in IPAzyme: 85.7%, 83.3%, 90.9%, respectively and in HITAZYME: 82.9%, 75%, 100%, respectively. These results are almost the same as micro-IF: 85.7%, 79.2%, 100%, respectively. These kits may have relatively high sensitivity and specificity in IgG antibody detection. In IgA detection, the total agreement between W-B and sero-IPALISA was 82.9%, positive agreement 100%, negative agreement 66.7%, in IPAzyme: 77.1%, 58.8%, 94.4%, respectively and in HITAZYME: 65.7%, 64.7%, 66.7%, respectively and in micro-IF: 82.9%, 70.6%, 94.9%, respectively. Although these agreements are not so high in IgA detection, the W-B technique gives fairly consistent results as well as those kits. This indicates that W-B technique with MOMP and other protein bands (40-62 KDa) as marker for positive reaction is a useful method for detection of chlamydial antibodies.

Antibodies, Bacterial↗
PubMed1996

RANTES mRNA expression in skin and colon of patients with atopic dermatitis.

The expression of RANTES mRNA in dermal and colonic tissue was examined in patients with atopic dermatitis by the reverse transcription polymerase chain reaction method. RANTES mRNA was detected in the colon in 8 of 10 patients and in 1 of 5 control patients. It was present in rashes in 9 of 10 patients and at non-eruptive sites in 5 of 7 patients. These findings suggest that RANTES is involved in eosinophil infiltration and T cell infiltration in atopic dermatitis.

Adolescent↗
PubMed1996

Corticosteroid-induced apoptosis of eosinophils in atopic dermatitis patients.

We examined the mechanism by which steroid administration significantly decreases the high eosinophil cell count in peripheral blood in patients with atopic dermatitis (AD). Eosinophils were isolated from the peripheral blood of patients with moderate or severe adult AD, and cultured. After steroid was added to the culture medium, we examined the changes in eosinophils, i.e., 1) the survival rates, 2) morphological changes and 3) fragmentation of DNA with respect to 2 factors, the steroid concentration and culture time. The steroid or interleukin-5 (IL-5) were added to eosinophils from patients with AD and those from non-AD patients with eosinophilia to compare serial changes in the survival rate. In eosinophils from patients with AD, the survival rate significantly decreased time-dependently and steroid concentration-dependently. Steroid administration significantly inhibited the survival rate of eosinophils from patients with AD compared to the survival rates of monocytes and neutrophils. The nuclei of eosinophils were serially reduced, and disappeared 72 hours after steroid administration. Simultaneously, cell size decreased, although the cell membrane remained intact. Granules developed in the cell membrane. In the steroid-treated group, apoptotic cells appeared earlier than in the untreated group. The number of cells showing apoptosis was increased steroid concentration-dependently. The number of DNA ladders was increased time-dependently and steroid concentration-dependently. In eosinophils derived from patients with AD and those derived from non-AD patients with eosinophilia, treatment with recombinant human (rh) IL-5 prolonged the life-span of cells. However, there were differences in the survival rates. In the presence of rhIL-5, the eosinophils from non-AD patients survived 1.4 times longer than those from AD patients at 24 hours (P < 0.05). In the presence of steroid, the eosinophils from non-AD patients survived twice as long as those from AD patients at 24 hours (P < 0.01). These findings suggest that apoptosis induced by steroids decreases the eosinophil count in vivo in patients with AD. There may be a difference in the incidence of steroid-induced apoptosis between eosinophil cells from patients with AD and those from patients with eosinophilia due to other underlying diseases.

Adolescent↗
PubMed1996

Elevated plasma RANTES levels in patients with atopic dermatitis.

Eosinophils and T cells are involved in the pathologic process of atopic dermatitis. To further understand the role of these cells, and the possible involvement of RANTES, in the pathogenesis of atopic dermatitis, we measured the plasma level of RANTES using the sandwich ELISA. The mean plasma level of RANTES in 11 patients with atopic dermatitis was significantly higher than that of 15 normal control subjects. RANTES levels were higher in patients with severe form of atopic dermatitis than that of patients with mild disease. These findings suggest that RANTES may play a role in the recruitment and activation of eosinophils and T cells in atopic dermatitis.

Adolescent↗
PubMed1996

Mechanisms of glucocorticoid resistance in human leukemic cells: implication of abnormal 90 and 70 kDa heat shock proteins.

The unliganded glucocorticoid receptor is a multi-oligomer complex consisting of a ligand-binding protein with which two 90 kDa heat shock proteins (hsp90s) are associated. Upon binding of glucocorticoid to the receptor, the ligand-binding protein, which dissociated from hsp90s, enters the nucleus, binds to a specific site in DNA, and thus transmits signal(s). The 70 kDa heat shock protein (hsp70) also works as a molecular chaperone when the ligand-binding protein enters the nucleus. Regarding the mechanisms of glucocorticoid resistance, a decreased expression of glucocorticoid receptor and a mutant protein with low ligand binding affinity have been reported. In the present study, to address other mechanisms of glucocorticoid resistance, we examined the expression of hsp90 and hsp70 in addition to the number of glucocorticoid-binding sites and their affinity using glucocorticoid-sensitive and -resistant human leukemic cell lines. We showed that two of nine resistant cell lines with normal glucocorticoid-binding proteins express aberrant hsp90 and extremely low hsp70, while another seven resistant cell lines had decreased binding sites with normal hsps. These results suggest that there are at least two independent mechanisms of glucocorticoid resistance in human leukemic cell lines: the decreased ligand-binding sites and the abnormal hsps expression.

Antineoplastic Agents, Hormonal↗
PubMed1996

Serum levels of anti-Staphylococcus aureus-specific IgE in patients with atopic dermatitis.

We investigated the role of Staphylococcus aureus-specific IgE in patients with atopic dermatitis (AD). The titer of serum S. aureus-specific IgE was measured using the RAST method in 67 patients with AD and correlated with serum LDH, eosinophil count and total IgE. The titer of S. aureus-specific IgE was elevated in 41 patients but was not detected in 26 patients. The mean serum level of total IgE was higher in the positive group than in the negative group, but the eosinophil count and LDH levels were not different between the two groups. S. aureus was detected and cultured from the skin of 33/41 (80%) patients in the positive group, but only from the skin of 5/26 (19%) patients of the negative group. Our results suggest that S. aureus-specific antibody is present in patients with moderate-to-severe atopic dermatitis and may be involved in the pathogenesis of AD.

Adolescent↗
PubMed1995

Detection of varicella-zoster virus DNA in maternal breast milk from a mother with herpes zoster.

BACKGROUND: We previously reported that varicella-zoster virus (VZV) DNA was detected by polymerase chain reaction (PCR) from maternal breast milk of a post-partum mother with chickenpox. OBJECTIVES: We tried to decide the route of VZV contamination to maternal milk. CASE REPORT: A 22-year-old woman developed herpes zoster on her right Th3-4 dermatome. RESULTS AND CONCLUSIONS: VZV DNA was detected by PCR from peripheral blood and the maternal milk of the right breast, but not from the maternal milk of the left breast. These results suggest that VZV in maternal milk may not derive from VZV-infected mononuclear cells in peripheral blood, but from the VZV-infected epitheliums of the lacteal gland.

Journal Article↗
PubMed1995

Exanthem subitum (roseola infantum) with vesicular lesions.

We report a 7-month-old boy who developed vesicular lesions during the course of exanthem subitum. Human herpesvirus-6 (HHV-6) DNA was detected both in the skin lesions and in the throat, by polymerase chain reaction. IgG and IgM antibodies against HHV-6 were 1:10 and < 1:10, respectively on the tenth day of the illness, and > 1:640 and 1:10 on the twenty-second day, respectively. These results suggest that this was primary HHV-6 infection.

Antibodies, Viral↗
PubMed1995

Expression of granulocyte colony-stimulating factor receptor on CD10-positive human B-cell precursors.

We examined the expression of CD10 and G-CSF receptor (G-CSFR) on the lymphoid population of mononuclear cells obtained from bone marrow (BM) using two-colour analysis. In the BM of children with ALL in remission, the CD10+ population was significantly increased (20.6 +/- 5.1% compared with that of controls (2.5 +/- 0.5%). More than half (61.3 +/- 2.9%) of the CD10+ cells co-expressed G-CSFR, but not CD13. These results indicate G-CSFR+ B-cell precursors are markedly increased in BM of ALL in remission, suggesting the probable involvement of G-CSF in the human early B-cell ontogeny.

Adolescent↗
PubMed1995

[Bacteriological, pharmacokinetic and clinical studies of SY5555 dry syrup in the pediatric field].

Bacteriological, pharmacokinetic and clinical studies on SY5555 dry syrup (powder which is dissolved before use), a new penem antibiotic for oral use, were performed. The following results were obtained. 1. Antibacterial activities. MICs of SY5555, clavulanic acid/amoxicillin (CVA/AMPC), cefotiam (CTM), cefpodoxime (CPDX), cefaclor (CCL) and cefdinir (CFDN) were determined against clinically isolated Staphylococcus aureus, coagulase negative staphylococci, Streptococcus pneumoniae, Streptococcus pyogenes, Haemophilus influenzae, Moraxella catarrhalis, Escherichia coli and Enterobacter cloacae at a dose of 10(6) CFU/ml. MICs of SY5555 against S. aureus, CNS, S. pneumoniae, S. pyogenes, H. influenzae, M. catarrhalis, E. coli and E. cloacae were 0.2, 0.2, 0.2, < or = 0.025, 0.78, 0.2, 0.78 and 3.13 micrograms/ml, respectively, showing excellent antibacterial effects on these pathogens. Although the effects of SY 5555 against H. influenzae and E. coli were slightly inferior to those of CPDX and CFDN, the drug showed the most excellent antibacterial effect on other strains as compared with the control drugs. 2. Absorption and excretion In this study, plasma concentrations and urinary recovery rates were examined after administration of SY5555 at doses of 5 and 10 mg/kg (potency) after meals. With both 5 and 10 mg/kg doses, peak plasma concentrations were reached 1 hour after administration, at 0.25-2.61 micrograms/ml (mean 1.47 micrograms/ml) and 1.08-2.17 micrograms/ml (mean 1.74 micrograms/ml), respectively. The plasma levels rapidly decreased to 0.06-0.19 micrograms/ml (0.12 micrograms/ml) and 0.0503-0.0637 micrograms/ml) after 6 hours. The half-lives 1.12 hours in the 5 mg/kg group and 1.0 hour in the 10 mg/kg group. The urinary recovery rates were determined in the first 8 hours after administration in the 5 mg/kg and 6 hours in the 10 mg/kg group, and the values were as low as 1.05-12.3% and 1.6-4.33%, respectively. 3. Clinical results The clinical responses were examined in a total of 73 cases including 4 acute pneumonia, 13 acute bronchitis, 11 tonsillitis, 3 pharyngitis, 12 scarlet fever, 2 pertussis, 6 urinary tract infection, 6 otitis media, 7 lymphadenitis, 2 staphylococcal scalded skin syndrome, 2 phlegmon, 4 impetigo and 1 purulent parotitis. The treatment was effective or better in 66 of 70 cases with an efficacy rate of 94.3% (3 undeterminable cases were excluded). Bacteriological effects were examined during the clinical course for detected or suspected pathogens found before administration of SY5555. The effects were determined in 50 cases including 7 cases of polymicrobacterial infections, 57 strains in total. Eight strains, however, persisted, hence the overall eradication rate was 86.0%.(ABSTRACT TRUNCATED AT 400 WORDS)

Absorption↗
PubMed1994

Inhibition of growth and cysteine proteinase activity of Staphylococcus aureus V8 by phosphorylated cystatin alpha in skin cornified envelope.

The activity of a cysteine proteinase purified from Staphylococcus aureus V8 (SAV8) was inhibited by phosphorylated cystatin alpha (P-cystatin alpha) and by purified cornified envelope protein of newborn rat, a conjugated form of P-cystatin alpha. Immunohistochemical analysis demonstrated a marked decrease in P-cystatin alpha content in cornified envelope treated with sphingosine. The inhibition of papain activity by proteins from sphingosine-treated skin was much weaker than that exerted by proteins from the untreated skin. The suppression of SAV8 colony formation inoculated on the sphingosine-treated skin was examined. Colony formation on the sphingosine-treated skin was enhanced compared to that on normal skin. These findings suggest that P-cystatin alpha in the cornified envelope may have a bacteriostatic barrier function against bacterial infection, such as that with SAV8.

Animals↗
PubMed1994

Identification and structural determination of the KDN-containing N-linked glycan chains consisting of bi- and triantennary complex-type units of KDN-glycoprotein previously isolated from rainbow trout vitelline envelopes.

KDN-gp, which is the unique glycoprotein of the rainbow trout egg envelope, was shown to have a small amount of N-linked oligosaccharide units in addition to a large number of O-linked glycan units. Structural analysis based on chemical analysis in combination with 400 MHz 1H NMR spectroscopy revealed the presence of fully KDNosylated bi- and triantennary complex-type oligosaccharide chains, mostly fucosylated at the innermost GlcNAc residue and bisected by the GlcNAc residue linked beta 1-->4 to the beta-Man residue. The structures thus determined represent the first demonstration of N-linked glycan unit containing the KDN residues in the KDN-containing glycoproteins (see Chart 1). The KDN-gp of the rainbow trout egg envelope is a molecule that is present in the second layer of the vitelline envelope but is exposed to the outer surface around the micropyle through which sperm can get in at fertilization. Like human hematopoietic cell surface glycoproteins such as glycophorin A and leukosialin, KDN-gp, which is now characterized to contain N-linked complex-type glycan chains as minor components, is heavily O-glycosylated with alpha 2-->8-linked oligo/polyKDN-containing glycan units attached O-glycosidically to Ser/Thr residues. Although little is known about the functional roles of these glycan chains, KDN-gp appears to form a model for further study on the function of cell surface receptor for sperm in fertilization.

Animals↗
PubMed1994

Linkage between phosphorylated cystatin alpha and filaggrin by epidermal transglutaminase as a model of cornified envelope and inhibition of cathepsin L activity by cornified envelope and the conjugated cystatin alpha.

Lysine-rich phosphorylated cystatin alpha (P-cystatin alpha) from newborn rat epidermis is a good substrate for epidermal transglutaminase (TGase) and also one of the component proteins of cornified envelope in the stratum corneum. Since the filaggrin linker segment peptide was efficiently conjugated with P-cystatin alpha and was mediated by epidermal TGase in the presence of Ca2+ ions, filaggrin is a candidate for the glutamine-rich linkage protein to conjugate with lysine-rich P-cystatin alpha. A conjugated protein was found by epidermal TGase in the activated condition with Ca2+ ions and dithiothreitol. In contrast, the conjugated protein was not formed under chelated conditions with EDTA. The conjugated protein reacted positively with anti-P-cystatin alpha polyclonal antibody (PoAb). The conjugated protein and purified cornified envelope showed an inhibitory effect against papain and cathepsin L, but cathepsin B and H were not inhibited by these P-cystatin alpha conjugates. Although the component protein, P-cystatin alpha itself, inhibited cathepsin H strongly, these conjugated proteins inhibited specifically the cathepsin L family. The amino acid composition of cornified envelope protein and the conjugated protein of P-cystatin alpha and filaggrin linker segment peptide was not completely the same. The conjugated protein of P-cystatin alpha and filaggrin linker segment peptide showed the same inhibitory properties against cysteine proteinases as the cornified envelope. These findings suggest that the linkage protein between P-cystatin alpha and filaggrin linker segment peptide may be considered a model of cornified envelope, although skin cornified envelope may be conjugated with some additional proteins.

Amino Acid Sequence↗
PubMed1994

A novel monoclonal antibody to the outer root sheath cells.

A novel monoclonal antibody to hair keratins (TYHF-1) which recognized a doublet of 43/44-kDa hair keratins in the immunoblot analysis was developed. TYHF-1 strongly reacted with the outer root sheath cells at the region of prekeratinization, the keratogeneous zone and the lower part of the isthmus portion in the indirect immunofluorescent examination. The cells of the inner root sheath and cuticle in the upper bulbar portion were also stained with this antibody. In addition, the tongue and nail matrix were also reacted with TYHF-1. However, TYHF-1 reacted with no epidermal keratins either in the indirect immunofluorescent examination or by immunoblot analysis using plantar epidermis. In addition, the cells of the eccrine and apocrine sweat glands, the epithelia of the buccal mucosa, larynx, tonsil, oesophagus, liver, intestine, gallbladder and urinary bladder demonstrated no positive reaction.

Animals↗
PubMed1994

Rapid purification of yeast cytoplasmic fumarate reductase by affinity chromatography on blue sepharose CL-6B.

The rapid and effective purification of soluble fumarate reductase from baker's yeast achieved by Blue Sepharose CL-6B chromatography. Cibacron Blue F3GA, the chromophore of Blue Sepharose, inhibited the activity of fumarate reductase. The enzyme bound to the column was selectively eluted by flavin adenine dinucleotide (FAD), flavin mononucleotide (FMN) or riboflavin. The purified enzyme was essentially homogeneous as indicated by polyacrylamide gel electrophoresis under nondenaturing conditions and under denaturing conditions in sodium dodecylsulfate. By this procedure, the enzyme could be rapidly purified with high yield from yeast cells.

Chromatography, Affinity↗