Search PubMed⌕ Search

Biomedical subjects

H Mizutani

Publications and source records attributed to H Mizutani.

At least 55 records · Page 3Linked to original sources
PubMed1999

Ultrastructural study on adhesions in internal derangement of the temporomandibular joint.

PURPOSE: This study examined the ultrastructural characteristics of adhesions in the upper joint compartment of temporomandibular joint (TMJ). MATERIALS AND METHODS: Tissue biopsy specimens of adhesions were obtained during arthroscopic operation on 36 joints in 22 patients with internal derangement (ID). The biopsy specimens were examined by light and transmission electron microscopy. RESULTS: Adhesions were grossly divided into two types based on arthroscopic observation: 1) a band-like type, which connected the articular fossa and TMJ disc, and 2) a pseudowall-like type, which faced the synovial fluid and was lined by articular tissue. Two types of collagen arrangement were observed at the electron microscopic level: orderly arranged collagen bundles and randomly arranged collagen bundles. Orderly arranged collagen bundles were prominent in the band-like adhesions. In pseudowall-like adhesions, mainly the randomly arranged collagen bundles were seen. However, in some dense fiber parts, orderly arranged collagen bundles also were observed. In other pseudowall-like adhesions, only orderly arranged collagen bundles were seen. Elastic fibers were abundant in some pseudowall-like adhesions with randomly arranged collagen bundles. There were no elastic fibers in the band-like adhesions, some dense fiber parts of the pseudowall-like adhesion, pseudowall-like adhesions consisting of only orderly arranged collagen bundles, and in the synovial membrane. CONCLUSION: The different arrangement of collagen fibers and presence or absence of elastic fibers were observed in the two types of adhesions. These findings served to show that extracellular components correspond to a dysfunction involving an ID of TMJ.

Adult↗
PubMed1999

Melanocyte melanin augments sparfloxacin-induced phototoxicity.

Quinolone has become one of the common causative agents of drug-induced photosensitive dermatitis, and its phototoxicity has now become a clinical issue. The mechanisms of long-lasting phototoxicity induced by sparfloxacin (SPFX) were investigated using melanotic and amelanotic melanoma cell lines. The sensitivities to SPFX and UVA irradiation up to 6 J/cm2 of both cells were not significantly different. However, the melanotic melanoma cell cultured with 1-150 microg/ml of SPFX showed significantly higher sensitivity to UVA irradiation compared with that of the amelanotic melanoma cell. By pulse culture with SPFX, the bound SPFX level of melanotic cell line was 10-20 times higher than that of the amelanotic cell line. These data strongly suggest that the melanin in melanocytes and keratinocytes accumulates the antibacterial quinolone and increases its tissue concentration in the basal epidermis and contributes to the long-lasting photo-injury and liquefaction degeneration of the basal cells in antibiotic quinolone phototoxic dermatitis.

Anti-Infective Agents↗
PubMed1999

Intradermal transfer of caspase-1 (CASP1) DNA into mouse dissects: role of CASP1 in interleukin-1beta associated skin inflammation and apoptotic cell death.

Caspase-1 (CASP1) interleukin-1beta (IL-1beta) converting enzyme (ICE) has been cloned as a specific enzyme which activates the biologically inactive pro-form of IL-1beta into biological active IL-1beta. Based on the significant homology to Ced-3, Caenorhabditis elegans apoptotic gene and, proof of apoptotic activity of ICE in rat fibroblasts, ICE was renamed as CASP1. In contrast to in vitro functions, the in vivo significance of high expression of CASP1 in skin remains to be elucidated. We transferred plasmid DNA encoding murine CASP1 with beta-actin promoter into mouse skin. The CASP1 DNA-injected skin, but not skin injected with control plasmid without CASP1, developed localized erythema with subcutaneous nodules. The nodules were associated with marked inflammatory infiltrates. The apoptotic cells detected by the TUNEL method were distributed in and around the inflammatory foci. The plasma IL-1beta level of CASP1 DNA-injected mouse was elevated compared with that of the control DNA-injected mouse. These inflammatory reactions of CASP1 DNA-injected skin were suppressed by treatment with neutralizing anti-murine IL-1beta antibodies, but the TUNEL positive apoptotic cells were still detected. This study clearly demonstrate dual roles of CASP1 in causing IL-1beta associated granulomatous skin infiltration and inducing apoptotic cell death in vivo.

Animals↗
PubMed1999

Tocoretinate inhibited the contraction of collagen gel matrices by human dermal fibroblasts with tenascin-C expression.

Retinoids are strong tissue modifiers and have been used to treat severe acne, keloids and photo-aged skin. Tocoretinate (TR), ester bound retinoic acid and tocopherol, has been topically applied for skin ulcers and, more recently, for sclerotic skin diseases. To clarify the mechanism of tissue softening by retinoids and TR, we investigated their effects on the contraction of hydrated type-1 collagen gel matrices by human dermal fibroblasts and on tenascin-C expression. TR, 13-cis-retinoic acid/isotretinoin and all trans-retinoic acid significantly inhibited collagen gel matrices contraction at concentrations from 10(-4) to 10(-8) M without significant changes of the fibroblast growth. TR and the other two retinoids dose-dependently induced tenascin-C expression in the fibroblasts. Since tenascin-C is involved in cellular detachment and tissue remodeling, these results suggest that TR and other retinoids down-regulated the tensile tension of fibroblasts in collagen gel matrices by the induction of tenascin-C.

Cells, Cultured↗
PubMed1999

Preliminary studies on hepatic carnitine palmitoyltransferase in dairy cattle with or without fatty liver.

The hepatic mitochondrial carnitine palmitoyltransferase (CPT) activity was measured by fluorimetric assay in dairy cows with or without fatty liver. CPT activities in 13 lactating cattle and in 6 non-lactating cows were 304.4+/-86.6 micromol CoA/min per g protein and 169.3+/-84.8 micromol CoA/min per g protein, respectively. This difference was significant (p < 0.05). CPT activities in early lactation (0-110 days after calving), mid-lactation (111-220 days after calving) and late lactation (over 220 days after calving) were 278.9+/-68.0, 312.4+/-124.1 and 320+/-59.3 micromol CoA/min per g protein, respectively. There was no significant difference between the values at different stages of lactation. The CPT activity in 10 lactating cows with fatty liver unrelated to calving was 201.3+/-80.0 micromol CoA/min per g protein. CPT activity in 10 cattle with fatty liver was significantly lower than that in normal lactating cattle. Based on these findings, clinical fatty liver unrelated to calving appears to be associated with a decrease in hepatic CPT activity.

Animals↗
PubMed1999

Anti-elongation factor-1alpha autoantibody in adult atopic dermatitis patients.

Adult atopic dermatitis (AD) patients develop severe facial lesions, which sometimes distribute in sun-exposed areas similar to the rash of systemic lupus erythematosus. To declare autoimmunity in the pathogenesis of AD, we investigated serum antinuclear antibody (ANA) in 256 adult AD patients and identified its ligands. A high titer of ANA was found in 31.3% of AD patients and 75% of the ANA showed a homogenous pattern. Sixty-five percent of ANA(+) sera reacted to a 52 kDa protein (p52) in HeLa cell immunoblots. By screening the HeLa cell cDNA expression library with anti-p52 sera, a clearly positive clone was isolated. The sequence of this cDNA was identical to human elongation factor (hEF)-1alpha. The eluate of IgG bound to hEF-1alpha-glutathione S-transferase (GST) fusion protein recognized a band at 52 kDa in a HeLa cell immunoblot, and stained Hep-2 cell nuclei and cytoplasma as reported in hEF-1alpha distribution. The anti-p52 AD sera recognized the hEF-1alpha-GST fusion protein. The anti-hEF-1alpha antibody-positive AD patients were characterized by higher facial involvement and lower white blood cell counts compared with antibody-negative patients. The present results suggest the possible involvement of autoimmunity in the pathogenesis of adult AD.

Adult↗
PubMed1999

Topical tocoretinate improved hypertrophic scar, skin sclerosis in systemic sclerosis and morphea.

Four patients with systemic scleroderma (SSc), 4 patients with morphea, and 4 patients with hypertrophic scar were treated with topical tocoretinate for 6 months to 3 years and studied clinically and histopathologically. Clinically, all of the lesions responded to this therapy. The stiffness of the skin lesions, glossy appearance of the lesions, and telangiectasia improved. Histopathologically, the proliferated collagen fibers decreased in thickness, and the inter-fiber spaces increased. Immunoreactive tenascin-C expressed in the proliferated deep dermal fibers of the SSc and hypertrophic scar lesions was markedly decreased compared with the level before the topical tocoretinate therapy. Topical tocoretinate has been used for the treatment of ulcers; it is also a potent treatment for sclerotic skin diseases.

Administration, Topical↗
PubMed1999

Overproduction of Th2-specific chemokines in NC/Nga mice exhibiting atopic dermatitis-like lesions.

We have examined the expression of chemokines and their receptors in the atopic dermatitis-like (AD-like) lesions of NC/Nga mice. Such lesions develop when the mice are kept in conventional conditions, but not when they are kept isolated from specific pathogens. The thymus- and activation-regulated chemokine TARC is unexpectedly highly expressed in the basal epidermis of 14-week-old mice with lesions, whereas it is not expressed in the skin without lesions. Production of TARC by keratinocytes was confirmed by culturing murine keratinocytic cell line cells (PAM212) with TNF-alpha, IFN-gamma, or IL-1beta. Expression of another Th2 chemokine, macrophage-derived chemokine (MDC), was observed in the skin from mice kept in both conventional and pathogen-free conditions, but expression of MDC was increased severalfold in the skin with lesions. The cellular origin of MDC was identified to be dermal dendritic cells. Infiltration of the skin by IL-4-producing T cells and mast cells, and the increase of CCR4 mRNA in the skin, coincided with the development of AD lesions. These observations indicate that TARC and MDC actively participate in the pathogenesis of AD-like lesions in NC/Nga mice and that these Th2 chemokines could be novel targets for intervention therapy of AD in humans.

Adrenal Cortex Hormones↗
PubMed1999

Trichofolliculoma of the upper lip: report of a case.

A trichofolliculoma occurring in the mid-philtrum of the upper lip of a 17-year-old boy is reported. It presented as an asymptomatic, 10 mm deep sinus and histology showed keratin-filled cysts or sinuses lined by stratified squamous epithelium.

Adolescent↗
PubMed1999

[Predicted versus actual postoperative refractive error after simultaneous vitrectomy and cataract surgery].

PURPOSE: We compared the spread between predicted and postoperative actual refractive errors after simultaneous vitrectomy, phacoemulsification, aspiration, and acryl lens insertion and after cataract surgery alone. METHODS: Cataract surgery and vitrectomy (combined surgery group) were performed in 185 eyes, and cataract surgery only (cataract surgery group) in 63 eyes. Vitrectomy was needed for diabetic retinopathy in 104 eyes, macular hole in 26 eyes, rhegmatogenous retinal detachment in 25 eyes, and other conditions in 30 eyes. RESULTS: The spread between predicted and actual refractive errors were +0.19 +/- 1.24 D (mean +/- standard deviation) in the combined surgery group and +0.91 +/- 1.40 D in the cataract surgery group. Gas tamponade in the combined surgery group increased the myopic change more than anything else. CONCLUSION: Actual refractive errors in the combined surgery group were found to shift to myopia more than in the cataract surgery group. Gas tamponade was considered to press the intraocular lens forward in the combined surgery group.

Adult↗
PubMed1999

[Endocrine chemotherapy (high-dose toremifene + 5'-DFUR) found markedly effective for 2 cases of metastatic breast cancer].

Two cases of metastatic breast cancer are reported in which endocrine chemotherapy with Toremifene + 5'-DFUR proved markedly effective. Case 1: A 69-year-old female. After CAF therapy as a adjuvant chemotherapy, Tamoxifen and Tegafur had been administered. At the 5th postoperative year, multiple metastases to lung and a rise in the tumor marker were found. Since the patient was not desirous of intensive chemotherapy, administration of Toremifene 120 mg/day and 5'-DFUR 800 mg/day was initiated. The patient showed PR 9 months after and achieved CR 14 months later. Case 2: A 48-year-old female. CAF therapy for a total of 6 cycles was performed as adjuvant chemotherapy. The patient was administered Tamoxifen and followed. On bone scintigrams 3.5 years after surgery, an abnormal accumulation appeared in the left sternoclavicular joint, and an infiltrative tumor mass was formed in the skin of that region. Administration of Toremifene + 5'-DFUR was initiated. After 6 months, the infiltrative mass disappeared. These findings are suggestive of the effectiveness of this combined chemotherapy.

Aged↗
PubMed1999

[Primary lung cancer (adenocarcinoma) associated with cardiac sarcoidosis].

A 56-year-old woman who had been given oral prednisolone for iridocyclitis by an ophthalmologist received a diagnosis of pulmonary sarcoidosis on the basis of transbronchial lung biopsy findings, and began receiving therapy at our hospital on an outpatient basis. Chest X-ray films disclosed hilar lymphadenopathy in both lungs. In addition, Holter electrocardiograms detected ventricular premature beat (Lown 4B) and echocardiograms detected reduced left ventricular wall motion with dilatation of the left ventricular chamber. Cardiac sarcoidosis developed in the patient. She was admitted to our hospital because of shortness of breath on exertion. Chest X-ray films on admission disclosed a large nodular heterogeneous mass in the right upper lobe. Histologically, transbronchial lung biopsy specimens of the mass disclosed an adenocarcinoma. Although lung cancer and sarcoidosis are common, their coexistence in the same patient is not. Furthermore, the coexistence of lung cancer with cardiac sarcoidosis, as in this case, is very rare.

Adenocarcinoma↗
PubMed1999

[Two cases of Kimura's disease associated with bronchial asthma].

We encountered two rare cases of Kimura's disease associated with bronchial asthma presenting eosinophilia and hyperimmunoglobulinemia E. Patient 1 was a 26-year-old man who had been admitted to our hospital with recurrent increase in left parotid mass in May 1997. He had previously undergone surgery for local excision at another hospital in September 1987; the excised specimens were re-evaluated and the diagnosis of Kimura's disease was confirmed. Because the patient was suffering from an acute asthma attack on admission, prednisolone (PSL) 30 mg/day was administered orally. PSL reduced the parotid mass and improved control of the asthma. Patient 2 was an 18 year-old man who had been given a diagnosis of Kimura's disease on the basis of histologic findings from a biopsy specimen of a subcutaneous tumor in the left cheek in 1988. Following the diagnosis, the patient was treated with methotrexate for the first several months, and then with loxioprofen for 9 years, but the size of the mass remained unchanged. Bronchial asthma developed in this patient in 1995 and had been treated with theophylline. However, because this therapy caused a deterioration of asthma control, the patient was admitted to our hospital in October 1997 for the treatment of bronchial asthma. Inhaled corticosteroids (beclometasone 0.8 mg/day) in addition to theophylline alleviated the patient's asthma symptoms and yielded improved lung function. Because few cases of Kimura's disease associated with bronchial asthma have been reported, patients with eosinophilia and hyperimmunoglobulinemia E were not necessarily considered at high risk for the onset of bronchial asthma.

Adolescent↗
PubMed1998

Amyloid arthropathy of the hip joint: MR demonstration of presumed amyloid lesions in 152 patients with long-term hemodialysis.

The aim of this study was to determine the spectrum of MR findings of presumed amyloid arthropathy of the hip joints in patients on long-term hemodialysis. We prospectively performed T1- and T2-weighted spin-echo imaging on 152 consecutive patients on hemodialysis. The duration of hemodialysis ranged from 5 months to 24 years, 2 months (mean: 8 years, 8 months). The frequency, location, and signal intensity of bone lesions were assessed. In 12 cases with contrast-enhanced MR examination, enhancement pattern of bone lesions, synovial lesions, and intra-articular lesions were characterized. Bone lesions presumed to be amyloid deposits were identified in 60 patients (39%). Magnetic resonance imaging revealed that amyloid lesions were more extensive than anticipated by plain radiographs. All bone lesions showed decreased signal intensity on T1-weighted images. On T2-weighted images, bone lesions showed increased signal intensity in 32 patients (54%), decreased signal intensity in 11 patients (18%), and both increased and decreased signal intensity in 17 patients (28%). Following intravenous injection of gadolinium-based contrast, all bone lesions showed moderate enhancement. Synovial thickening could not be identified on T1- and T2-weighted images. However, contrast-enhanced images showed thickened synovial membrane, which could be differentiated from joint fluid. Intra-articular nodules showed decreased or intermediate signal intensity on T1-weighted images and decreased signal intensity on T2-weighted images; the intra-articular nodules were contiguous with subchondral bone lesions. Magnetic resonance imaging is useful for evaluating the distribution and extent of amyloidosis of the hip joints in patients undergoing long-term hemodialysis.

Adult↗
PubMed1998

Sparfloxacin-induced photosensitivity and the occurrence of a lichenoid tissue reaction after prolonged exposure.

BACKGROUND: A new antibacterial quinolone, sparfloxacin (SPFX), frequently causes photosensitive dermatitis and sometimes induces a treatment-resistant lichenoid tissue reaction (LTR). OBJECTIVE: We attempted to determine the factors that induce LTR in SPFX-induced photodermatitis. METHODS: Thirteen patients with SPFX photosensitive dermatitis were studied clinically and histopathologically. RESULTS: Six of the 13 patients had acute dermatitis with epidermal spongiosis and focal epidermal HLA-DR and intercellular adhesion molecule-1 (ICAM-1) expression with CD4+ cell infiltration. The other seven displayed LTR with basal cell liquefaction degeneration and diffuse epidermal HLA-DR and ICAM-1 expression associated with CD8+ cells. The seven patients with LTR were exposed to UV and SPFX for more than 2 weeks after the appearance of their initial eruption, whereas the six patients with acute dermatitis were treated within 2 weeks. The acute dermatitis lesions cleared significantly within 2 weeks, but the LTR lesions persisted for more than 6 weeks. CONCLUSION: Patients with quinolone-induced photosensitivity should be treated within 2 weeks of onset to prevent LTR.

Adult↗
PubMed1998

Endogenous neutralizing anti-IL-1 alpha autoantibodies in inflammatory skin diseases: possible natural inhibitor for over expressed epidermal IL-1.

Interleukin 1alpha (IL-1alpha) is thought to play a central role in inflammatory reactions of the skin. Its excessive production and discharge by keratinocytes has been implicated in psoriasis, bullous diseases and other skin diseases. In addition to the type 2 IL-1 receptor and the IL-1 receptor antagonist, anti-IL-1 antibody in human serum has been proposed as a potential means to down regulate systemic responses attributable to IL-1. However, the relationship of these antibodies to disease and particularly to disease pathogenesis is still unclear. To understand this relationship, we characterized the anti-IL-1 autoantibody in sera from various skin diseases. IL-1alpha and IL-1beta radioimmunoassay, and immuno-blotting study showed the existence of IL-1alpha autoantibody but not autoantibodies to IL-1beta or pro-IL-1beta. High titer of anti-IL-1alpha autoantibodies were detected in the sera from inflammatory skin diseases with epidermal injury, including psoriasis, palmoplantar pustulosis, pustular psoriasis, pemphigus and lichen planus. In contrast, few samples from non-epidermodestructive bullous pemphigoid, atopic dermatitis and healthy normal controls had autoantibodies. The titer of anti-IL-1alpha autoantibodies showed some relation to the clinical course of psoriasis and pemphigus. Anti-IL-1 autoantibody neutralized rhIL-1alpha in D10.G4 assay and inhibited receptor binding of FITC-rhIL-1alpha. Taken together present data, the keratinocyte derived IL-1alpha could be a source of autoantigen that provokes production of endogenous anti-IL-1alpha autoantibody, which may regulate IL-1alpha mediated cutaneous inflammation.

Adult↗