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Biomedical subjects

M Mihara

Publications and source records attributed to M Mihara.

At least 163 records · Page 9Linked to original sources
PubMed1991

Linear focal elastosis. An ultrastructural study.

We studied an 86-year-old Japanese man with linear focal elastosis. The lesions were asymptomatic yellow striae in the lumbar region, histologically composed of massive, well-demarcated basophilic fibers that stained positively with elastic tissue stains. Electron microscopy revealed fine, reticular or granular electron-dense materials, and elastic fiber microfibril-like materials in the matrix, in addition to numerous mature and immature elastic fibers. These findings suggest that active elastogenesis was occurring in the lesions. The four cases reported so far have the three common features of age, sex, and lesion location.

Actin Cytoskeleton↗
PubMed1990

Retinal circulation times in quantitative fluorescein angiography.

We tried to obtain an overview of the quantitative state of the retinal circulation. Optical density measurements by an image analyzer were performed on video fluorescein angiograms for the determination of dyedilution curves. To ensure that curves with a sharp peak were obtained, 1 ml sodium fluorescein 10% was flushed with 20 ml physiological saline. From dilution curves of a retinal circulation times, T(x) (x = 1, 25, 50, 75, and 100) and Tm, were calculated. T(1) corresponds to the difference in the time of initial dye appearance; T(50), to the so-called half-maxim time difference; T(100), to the difference in the time to peak intensity; and Tm, to the mean circulation time. T(50) showed the best reproducibility when it was examined at 49 retinal regions of 10 healthy volunteers with a double video-fluorescein angiogram that was obtained within 1 min. Normal values (mean +/- SD) at the temporal superior region of 37 healthy volunteers were as follows: T(1) = 0.87 +/- 0.66 s, T(25) = 1.52 +/- 0.48 s, T(50) = 1.83 +/- 0.50 s, T(75) = 2.12 +/- 0.56 s, T(100) = 2.73 +/- 0.76 s, and Tm = 2.69 +/- 1.25 s. We believe that these values give a general overview of the quantitative state of normal retinal circulation.

Adolescent↗
PubMed1990

The local recurrence of pigmented Spitz nevus after removal.

A seventeen-month-old female had a pigmented nodule on her left lower leg. The excised lesion was histologically diagnosed as a Spitz nevus, composed mainly of spindle-shaped melanocytes containing large amounts of melanin pigment. When nodular regrowth was seen at the operative site, the recurrent lesion was radically excised as nodular melanoma. However the histological characteristics of the second excised specimen were essentially the same as those in the initially excised one except for the existence of the newly formed collagen fibers, which may suggest an involuting stage in the central portion of the lesion.

Diagnosis, Differential↗
PubMed1990

Immunologic abnormality in NZB/W F1 mice. Thymus-independent expansion of B cells responding to interleukin-6.

We have previously reported that B cell abnormality in NZB/W F1 mice developed independently of thymus. Here we examined further whether B cells from NZB/W F1 mice respond to interleukin-6 (IL-6), a factor for terminal differentiation of B cells. When freshly isolated splenic B cells were incubated for 5 days in the presence of human IL-6, an increased production of both IgM and IgG, including anti-DNA antibody, was evident in NZB/W F1 mice; there was no increase in BALB/c mice. A magnitude of augmentation in IgG but not IgM production by IL-6 became more apparent in older NZB/W F1 mice. The increased immunoglobulin production seen with IL-6 was neutralized by treatment with rabbit anti-recombinant human IL-6 antibody. As B cells from athymic NZB/W F1 nude mice also responded to IL-6, it was suggested that B cells in NZB/W F1 mice differentiated into the IL-6-responding state in a thymus-independent manner. This B cell abnormality may be associated with the pathogenesis of autoimmune disease in NZB/W F1 mice.

Animals↗
PubMed1990

A case of secondary cutaneous amyloidosis: epidermal keratinocytes produce amyloid in the cytoplasm.

A case of secondary localized cutaneous amyloidosis associated with a seborrheic keratosis is reported. Amyloid was observed both in the stroma and in the tumor. Light and electron microscopy revealed amyloid within the cytoplasm of the tumor cells. This intracytoplasmic amyloid was seen in basaloid cells or in the border areas between basaloid cells and squamous cells, but it was not seen in squamous cells. The amyloid was positive for anti-keratin antibody and contained disulfide bonds. It is suggested that either abnormal keratinization or the degeneration of basaloid cells produced abnormal keratin proteins that formed this amyloid.

Aged↗
PubMed1990

Possible role of IL-6 in pathogenesis of immune complex-mediated glomerulonephritis in NZB/W F1 mice: induction of IgG class anti-DNA autoantibody production.

This study demonstrates that interleukin-6 (IL-6) increases the autoantibody production by B cells from NZB/W F1 mice. Splenic B cells were cultured for 5 days in the presence or absence of human IL-6, and then the anti-DNA antibody and immunoglobulin contents in the culture supernatants were measured by ELISA. Adding IL-6 increased IgG anti-DNA antibody production by B cells from old mice (30 weeks), but not from young ones (17 weeks). B cells obtained from both young and old mice produced IgM anti-DNA antibody, which increased when IL-6 was added. The increased anti-DNA antibody production was suppressed by anti-recombinant human IL-6 antibody to the background level, i.e. antibody contents in the absence of IL-6. In contrast, murine IL-5 did not increase IgG anti-DNA antibody production, although it promoted the production of IgM anti-DNA antibody. Furthermore, when IL-5 was added in combination with IL-6, there was an additive increase in IgM, but not in IgG anti-DNA antibody production. Similar results were obtained in the measurement of the immunoglobulin contents. These results suggest the possible role of IL-6 in the pathogenesis of autoimmune disease in NZB/W F1 mice.

Animals↗
PubMed1990

Acantholytic pilomatricoma.

An 11-year-old girl had a slowly enlarging, painful, pink-red tumor on her scalp of 1 month's duration. The lesion was composed of several, round tumor cell nests in the dermis. Each nest was made up of peripheral basophilic cells and central shadow cells or eosinophilic materials. Occasionally the nests, having central eosinophilic degeneration, became epithelial cysts, some of which showed acantholytic changes in their cyst wall. This seems to be the first case of an acantholytic variant of pilomatricoma.

Acanthocytes↗
PubMed1990

Linear sebaceous nevus syndrome.

A boy with linear sebaceous nevus syndrome was followed up to 3 years of age, at which time he died of pneumonia. The lesions of nevus sebaceus were located in the midline and on both sides of the face, and there were partial colobomata of the right outer canthus continuous with pseudopterygium and of the left upper eyelid. At 2 months of age, the patient developed infantile spasms. At 1 year, electroencephalography revealed hypsarrhythmia, and left carotid angiography showed an arteriovenous malformation. At 2 years, the mental retardation and delayed motor development were detected.

Arteriovenous Malformations↗
PubMed1990

Simultaneous occurrence of calcification and amyloid deposit in pilomatricoma.

Amyloid deposition was encountered in 10 of 16 samples of pilomatricoma, indicating that the deposition of amyloid is nearly as common as calcification in pilomatricoma. In addition, a simultaneous occurrence of calcification and amyloid deposit in pilomatricoma was recognized in 9 of 16 samples. The calcification and the deposition of amyloid developed topographically in the same area within the shadow cell masses. Such an area was revealed as moderately basophilic, amorphous, or hyalinized by H&E staining. Electron microscopy revealed spotty calcium deposits in amyloid. No light chains of human immunoglobulin were detected in the amyloid-deposited area. Amyloid in this tumour may facilitate calcification or serve as a matrix for subsequent calcification.

Adolescent↗
PubMed1990

Microcystic adnexal carcinoma. Electron microscopic and immunohistochemical study.

We present a patient with microcystic adnexal carcinoma. The lesion was an indurated plaque on the skin of the right upper lip of a 58-year-old woman which was slowly growing during 27 years. Carcinoembryonic antigen was immunoreactive in the luminal contents of the tumor ducts and in the cytoplasm of cells surrounding ducts. S-100 protein was positive in the cytoplasm of a few cells at the lower dermis. These observations suggested that this tumor was related to sweat glands. Furthermore, electron microscopy revealed that tumor cells had features of eccrine ductal cells. These observations confirm that this tumor appeared at least capable of eccrine duct differentiation.

Carcinoembryonic Antigen↗
PubMed1990

Protective effect of the novel anti-ischemic agent 2-(4-(p-fluorobenzoyl)-piperidin-1-yl)-2'-acetonaphthone hydrochloride against ischemia-induced impairment of the passive avoidance response in gerbils.

E2001 (2-(4-(p-fluorobenzoyl)-piperidin-1-yl)-2'-acetonaphthone hydrochloride, CAS 107025-80-9) is a novel anti-ischemic agent, which is reported to protect against delayed neuronal death in the CA1 subfield of the hippocampus. The effect of E2001 on ischemia-induced impairment of the passive avoidance response in gerbils was studied. The passive avoidance response was not disturbed by transient cerebral ischemia of 3 min duration, but was impaired by 5-min ischemia. E2001 at oral doses of 3 and 10 mg/kg significantly improved the impaired passive avoidance response induced by 5-min cerebral ischemia. It is speculated that the improvement by E2001 may be partly due to the inhibition of extracellular glutamate accumulation, and the suppression of lipid peroxides formation during cerebral ischemia.

Animals↗
PubMed1989

Cutaneous focal mucinosis.

A 39-year-old man had typical cutaneous focal mucinosis on the left forearm. The fibroblasts in the myxomatous lesion had many cytoplasmic vesicles, and on electron microscopy, these were compatible with condensing vacuoles or secretory granules. The fibroblasts in this case were considered to be mucoblasts involved in the over-production of the ground substance, that was mainly composed of hyaluronic acid.

Adult↗
PubMed1989

Chondroid syringoma associated with hidrocystoma-like changes. Possible differentiation into eccrine gland. A histologic, immunohistochemical and electron microscopic study.

A case of chondroid syringoma associated with hidrocystoma-like changes was investigated by histology, immunohistochemistry and electron microscopy. Chondroid syringoma was histologically compatible with apocrine mixed tumor, and hidrocystoma-like changes did not fulfill diagnostic criteria of either eccrine hidrocystoma or apocrine hidrocystoma. However, epithelial cellular elements composing both chondroid syringoma and hidrocystoma-like changes suggested, immunohistochemically and electron microscopically, differentiation into eccrine gland. The lesions of both had an apparent transition of ductal structures of chondroid syringoma into hidrocystoma-like changes. Therefore, chondroid syringoma and hidrocystoma-like changes in this case may be organized as a peculiar type of cutaneous appendage tumor differentiating toward eccrine gland.

Adenoma, Sweat Gland↗
PubMed1989

The biological response modifier OK-432 (a streptococcal preparation) inhibits the development of autoimmune kidney disease in NZB/W F1 hybrid mice: possible involvement of tumor necrosis factor.

OK-432 (a streptococcal preparation) has been widely used for cancer immunotherapy in Japan. It is a potent immunostimulator, activating macrophages and T lymphocytes, and increasing the production of TNF and several other cytokines in both humans and animals. In the present study, we evaluated the prophylactic effect of OK-432 on the development of autoimmune kidney disease in NZB/W F1 (BWF1) mice. The mice were given 0.5 or 2.0 KE ('klinische Einheit'; clinical unit) of OK-432 intraperitoneally every week from 21 weeks of age to the time of death. The control group received the same volume of saline (vehicle). OK-432 delayed the development of proteinuria and prolonged the survival of these mice dose dependently. At 49 weeks, 33.3% of control mice were alive, whereas 55.6% in the 0.5-KE- and 75% in the 2.0-KE-treated mice were alive. In the control group, the serum cholesterol level increased due to the development of glomerulonephritis. In contrast, mice treated with OK-432 had significantly lower levels of serum cholesterol. The serum levels of anti-DNA and anti-TNP antibodies were not affected by OK-432 administration. OK-432 induced the production of tumor necrosis factor (TNF)-alpha in the peritoneal fluid in the BWF1 mice. These results indicate that the effect of OK-432 in preventing the development of autoimmune disease in the mice may result from the stimulation of the endogenous TNF-alpha production.

Animals↗
PubMed1989

Effect of several kinds of drugs on the development of autoimmunity in MRL/Mp-lpr/lpr mice; lack of correlation between the suppression of autoantibody production and prevention of autoimmune disease.

MRL/Mp-lpr/lpr (MRL/l) mice spontaneously develop autoimmune kidney disease which resembles human systemic lupus erythematosus (SLE). Employing this strain of mouse, we examined the effect of several immunosuppressants and a newly synthetized anti-nephritic agent, 4-chloro-3',6'-dimethyl-2,2'-iminodibenzoic acid (TO-115) on both the development of immunological abnormalities and the clinical symptoms of autoimmune kidney disease. This study aimed to determine how much the magnitude of autoantibody suppression related to the degree of prevention of autoimmune nephritis. Immunological abnormalities were assessed by measuring the serum levels of anti-deoxyribonucleic acid and anti-trinitrophenyl antibodies, rheumatoid factor (RF), and immune complex (IC). The status of autoimmune kidney disease was monitored by means of the appearance of proteinuria and survival time and the measurement of serum levels of blood urea nitrogen (BUN) and cholesterol. Immunosuppressants such as cyclophosphamide (CY), 6-mercaptopurine (6 MP) and sodium aurothiomalate (SAT) remarkably suppressed the development of immunological abnormalities in a dose dependent manner. Interestingly, however, only CY showed the suppressive effect on the development of autoimmune kidney disease with prolongation of survival time and the excretion of proteinuria. In contrast, 6-MP and SAT did not inhibit the development of autoimmune kidney disease. On the other hand, TO-115 did not suppress the development of immunological abnormalities, but it restrained the symptoms of autoimmune kidney disease. Taken together, the suppression of autoantibody production does not always lead to prevention of the development of autoimmune kidney disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

Anti-ischemic effect of the novel anti-ischemic agent 2-(4-(p-fluorobenzoyl)-piperidin-1-yl)-2'-acetonaphthone hydrochloride and possible mechanism of its action.

The protective effect of E-2001 (2-(4-(p-fluorobenzoyl)-piperidin-1-yl)-2'-acetonaphthone hydrochloride) was examined in various ischemic models, and the mechanisms of its action were investigated in vitro and in vivo. 1. Pretreatment with E-2001 ameliorated the degeneration of pyramidal neurons in the hippocampal CA1 sector following transient ischemia in Mongolian gerbils. 2. E-2001 improved stroke symptoms induced by permanent unilateral carotid artery ligation in gerbils. 3. E-2001 prolonged the survival time following permanent bilateral carotid artery ligation in gerbils and mice. E-2001 also prolonged the survival time following intravenous injection of KCN into mice. 4. E-2001 suppressed the high potassium-evoked release of glutamate from rat hippocampal slices. Furthermore, E-2001 prevented the excessive accumulation of extracellular glutamate induced by a brief ischemia in gerbils. 5. E-2001 exerted calcium antagonistic action, i.e., a relaxing effect on high potassium-induced contraction of rat aorta. 6. E-2001 exerted inhibitory action on the lipoperoxide production in vitro and in vivo, and exhibited a radical scavenging effect against O- and N-radicals. These results suggest that E-2001 might be effective as a novel anti-ischemic agent.

Animals↗
PubMed1989

Autoimmune kidney disease in MRL/Mp-lpr/lpr mice inhibited by OK-432, a streptococcal preparation.

Autoimmune MRL/Mp-lpr/lpr (MRL/l) mice were treated with the immunostimulating anti-cancer drug OK-432 (a streptococcal preparation), a potent inducer of tumour necrosis factor. Treatment was initiated at 8 weeks of age, before the onset of the autoimmune disease. OK-432 prevented the development of immune complex-mediated glomerulonephritis in a dose-dependent manner, and prolonged the life in this strain of mice. At 36 weeks of age, the incidence of proteinuria was 90% in the controls, 60% in the 0.5-KE(1 KE = 0.1 mg) treatment group, and 33% in the 2.0-KE group. The 50% survival time was 23 weeks for the controls; 32 weeks for the 0.5-KE group; and greater than 36 weeks for the 2.0-KE group. Immune complex deposition in glomeruli was significantly reduced in the treated groups. The IgM class of serum autoantibody levels was significantly increased by OK-432 treatment but the IgG class was almost unchanged. Furthermore, lymphadenopathy and splenomegaly were not suppressed. The results indicate that OK-432 may be useful in the treatment of autoimmune disease in humans.

Animals↗