Biomedical subjects

T Atsumi

Publications and source records attributed to T Atsumi.

At least 145 records · Page 8Linked to original sources

PubMed1995

Protective activity of hamamelitannin on cell damage of murine skin fibroblasts induced by UVB irradiation.

The protective activities of hamamelitannin (2',5-di-O-galloyl-hamamelose) in Hamamelis virginiana L. and its related compound, gallic acid, on damaged murine skin fibroblasts induced by UVB irradiation were investigated. In order to exclude the UV absorbing effect of the compounds, the protection study was performed such that the fibroblasts were pretreated with hamamelitannin or gallic acid for 24 h before UVB irradiation. At 200 microM concentration, hamamelitannin gave the higher survival of 72.6 +/- 0.4% in comparison with that of gallic acid (35.5 +/- 1.0%), while UVB absorbers such as 2-ethylhexyl p-methoxycinnamate and hexylbenzoate did not show such protection. The scavenging activities of hamamelitannin and gallic acid against active oxygens such as superoxide anion radicals, hydroxyl radicals and singlet oxygens were evaluated using electron spin resonance (ESR-spin trapping method). Hamamelitannin and gallic acid showed potent scavenging activities against all active oxygens tested. Furthermore, the association of hamamelitannin to fibroblasts was examined by comparing it with that of gallic acid, and the following results were obtained: (1) hamamelitannin reduces the reaction rate of liposome entrapped-nitroblue tetrazolium (NBT) with external superoxide anions, and (2) several glycosides associate with fibroblasts. From these results, it was concluded that hamamelitannin protects murine fibroblasts against external active oxygens by associating with the cell surface through its sugar moiety.

Animals↗

PubMed1995

Development of systemic lupus erythematosus after chemotherapy and radiotherapy for malignant thymoma.

Autoimmune conditions such as systemic lupus erythematosus (SLE) are sometimes associated with thymoma. Recently we drew attention to the development of SLE some months or even years following surgical thymectomy or thymomectomy. We now describe the first patient who developed SLE after chemotherapy and radiotherapy alone for malignant thymoma. A 38-yr-old female presented with an anterior mediastinal mass, which was found to be a malignant thymoma. Chemotherapy and radiotherapy were performed with complete resolution of the tumour. She remained stable for 4 yr, but then developed polyarthritis, lymphopenia, high titre anti-dsDNA antibody and antinuclear antibody. The diagnosis of SLE was established 44 months after malignant thymoma was treated. We believe that cases as this highlight the relationship between the thymus and the development of SLE.

Adult↗

PubMed1995

Isolation of the polar and lateral flagellum-defective mutants in Vibrio alginolyticus and identification of their flagellar driving energy sources.

Vibrio alginolyticus has two types of flagella (polar and lateral) in one cell. We isolated mutants with only a polar flagellum (Pof+ Laf-) or only lateral flagella (Pof- Laf+). Using these mutants, we demonstrated that the energy sources of the lateral and polar flagellar motors in V. alginolyticus are H+ and Na+ motive forces, respectively, as in the related species V. parahaemolyticus.

Carbonyl Cyanide m-Chlorophenyl Hydrazone↗

PubMed1995

A case of Crow-Fukase syndrome with elevated soluble interleukin-6 receptor in cerebrospinal fluid. Response to double-filtration plasmapheresis and corticosteroids.

We report the case of a 33-year-old Japanese male who presented with thrombocytosis, lower limb edema, severe polyneuropathy with elevated cerebrospinal fluid (CSF) protein level and serum IgA lambda monoclonal component, fulfilling the manifestations of Crow-Fukase syndrome. A high level of soluble interleukin-6 receptor in the CSF was also found, which fluctuated in parallel with the clinical course. Initial treatment with double-filtration plasmapheresis (DFPP) reduced the serum IgA paraprotein level with improvement of the sensory component of the polyneuropathy and decrease of soluble interleukin-6 receptor in the CSF. The remaining clinical features waned off after steroid treatment. The possible role of interleukin-6 in the pathogenesis of the Crow-Fukase syndrome and the utility of DFPP treatment are discussed.

Adult↗

PubMed1995

Severe hepatic involvement without inflammatory changes in systemic lupus erythematosus: report of two cases and review of the literature.

Hepatic diseases in systemic lupus erythematosus (SLE) are not rare, but liver biopsies of those cases are usually reported as chronic hepatitis or steroid-induced steatosis. We describe two unusual patients with active SLE who displayed liver dysfunction without inflammatory changes or associated with drug administration. A liver biopsy in case 1 showed massive hepatic cell damage resulting in acute hepatic failure. In case 2, the liver specimen revealed diffuse fatty degeneration without symptoms specific to liver dysfunction. No inflammatory cell infiltrate was observed in the liver tissue of either patient. After steroid pulse therapy (case 1) and the administration of 60 mg/day of prednisolone (case 2), liver function improved in parallel with the stabilization of the other manifestations of SLE. No other causes for liver damage except for SLE were observed in either case. Therefore it is supposed that the liver impairments in these cases were one manifestation of SLE.

Adult↗

PubMed1995

Active-oxygen scavenging activity of plant extracts.

To find antioxidative compounds present in plants, 65 types of plant extract were tested using the neotetrazolium method for evidence of superoxide anion-scavenging effects and 7 plant extracts were selected for further investigation. The activity of active-oxygen scavengers such as superoxide anion radicals, hydroxyl radicals, singlet oxygens and lipid peroxides in the 7 plant extracts (Aeseclus hippocastanum L., Hamamelis virginiana L. Polygonum cuspidatum Sieb., Quercus robur L., Rosemarinous officinalis L., Salvia officinalis L. and Sanguisorba officinalis L.) was examined in detail by both ESR spin-trapping and malondialdehyde generation. Furthermore, the active-oxygen scavenging activity of these plant extracts was evaluated using a murine dermal fibroblast culture system. Both Aeseclus hippocastanum L. and Hamamelis virginia L. were found to have strong active-oxygen scavenging activity of and protective activity against cell damage induced by active oxygen. Both Aeseclus hippocastanum L. and Hamamelis virginiana L. are proposed as potent plant extracts with potential application as anti-aging or anti-wrinkle material for the skin.

Animals↗

PubMed1995

Protective activity of hamamelitannin on cell damage induced by superoxide anion radicals in murine dermal fibroblasts.

Previously we demonstrated that hamamelitannin (2',5-di-O-galloyl hamamelose) in Hamamelis virginiana L. exhibits potent superoxide-anion scavenging activity. We then examined the physiological and pharmacological activities of hamamelitannin as well as its functional homologues, gallic acid and syringic acid. The following results were obtained: (1) Hamamelitannin has a higher protective activity against cell damages induced by superoxide anions than gallic acid which is the functional moiety of hamamelitannin. The protective activity of hamamelitannin on murine fibroblast-damage induced by superoxide anions was found at a minimum concentration of 50 microM, while the corresponding figure for gallic acid was 100 microM. (2) Pre-treatment of fibroblasts with hamamelitannin enhances cell survival. (3) The superoxide-anion scavenging activity of the compound in terms of its IC50 value (50% inhibition concentration of superoxide anion radicals generated) was evaluated by ESR spin-trapping. Both hamamelitannin (IC50 = 1.31 +/- 0.06 microM) and gallic acid (IC50 = 1.01 +/- 0.03 microM) exhibited high superoxide-anion scavenging activity followed by syringic acid (IC50 = 13.90 +/- 2.38 microM). (4) When hamamelitannin was treated with superoxide anions generated by a KO2-crown ether system, HPLC analysis showed the disappearance of hamamelitannin and the concomitant formation of hamamelitannin-derived radicals (g = 2.005, delta H1 = 2.16 G, delta H2 = 4.69 G) was detected by ESR spectrometry.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1995

[The association of the disease activity of rheumatoid factor positive vasculitis and the level of rheumatoid factor].

Rheumatoid factor (RF), an autoantibody against the Fc portion of denatured IgG, has long been recognized as an important biologic marker not only for rheumatoid arthritis but also for other auto-immune diseases. In this study, we measured the level of serum RF in four patients with RF positive systemic vasculitis using laser nephelometry. Three patients were diagnosed as polyarteritis nodosa and the other patient was diagnosed as systemic vasculitis without the finding of typical necrotizing vasculitis from biopsies. In the result, we found that the level of RF paralleled the disease activity in these cases. When active phase of the disease, the level of RF showed very high, and after the treatment combined with plasmapheresis, corticosteroid and immunosuppressive agent, the level of RF decreased in accordance with CRP, ESR and clinical features. These suggested that RF was the disease specific marker for RF positive vasculitis and beneficial informations for proper diagnosis and better treatment could be provided by measurement of the level of RF in patients with RF positive systemic vasculitis.

Adult↗

PubMed1995

Peroxyl radical scavenging activities of hamamelitannin in chemical and biological systems.

The antioxidative activities of hamamelitannin (2',5-di-O-galloyl-hamamelose), gallic acid and dl-alpha-tocopherol against lipid peroxyl radicals were evaluated in chemical and biological systems. The peroxyl radical scavenging activity was evaluated by electron spin resonance (ESR) method in which both spin-trapping and direct reaction methods were used. In the spin-trapping method, as evaluated by 50% inhibition concentration (IC50) of peroxyl radicals generated in a t-butylhydroperoxide-methemoglobin system, hamamelitannin (IC50 = 95.3 +/- 2.7 microM) showed the highest activity, followed by gallic acid (IC50 = 152.8 +/- 14.6 microM) and dl-alpha-tocopherol (IC50 = 221.5 +/- 4.6 microM) as a positive control. When estimating by the direct method, IC50 values of hamamelitannin, gallic acid and dl-alpha-tocopherol were 93.5 +/- 2.1 microM, 141.6 +/- 2.0 microM and 1590.0 +/- 330.0 microM, respectively. On peroxidation of lipid bilayers induced by 2,2'-azobis-(2-amidinopropane) dihydrochloride (AAPH) in terms of inhibition period (tinh), hamamelitannin showed the longest tinh time (1107.0 +/- 38.18 sec), followed by those of dl-alpha-tocopherol (877.5 +/- 31.8 sec) and gallic acid (771.0 +/- 4.2 sec). The kinetic chain length, defined as the propagation numbers of a lipid peroxyl radical, and calculated from the ratio (Rp/Ri) of the rate of lipid peroxidation to that of inhibition by dl-alpha-tocopherol, hamamelitannin and gallic acid were 27.23, 7.86 and 7.09, respectively. The effects of hamamelitannin, gallic acid and dl-alpha-tocopherol were evaluated on murine fibroblasts exposed to t-butylhydroperoxide (BHP) in terms of the cell survivals. In the protection, hamamelitannin induced the highest survival of 27.6 +/- 0.6% at 50 microM, while both gallic acid and dl-alpha-tocopherol were less active at the same concentrations. On the basis of the results, hamamelitannin was concluded to have a high protective activity on cell damage induced by peroxides.

Animals↗

PubMed1995

[A case of bilateral upper medial medullary infarction].

A clinical case of bilateral upper medial medullary infarction was reported. A 61-year-old woman was admitted to our hospital because of numbness of trunk and bilateral upper and lower limbs, aphonia and left-hemiparesis, which progressed to quadriplegia. Facial movements were intact. Her tongue was not fully protruded and deviated to the right side. Impairment of the position sense was noted in bilateral lower limbs. Respiratory failure was not observed. A brain MRI revealed a high-intensity area on T2-weighted imaging in the upper medulla oblongata. The lesion involved the medial medulla oblongata bilaterally. No lesions were present in the other brain parenchyma. According to the literature, respiratory failure was present in almost all patients with bilateral medial medullary infarction. The findings of our patient suggest that respiratory failure is not induced by the bilateral medial medullary infarction limited to the upper medulla oblongata.

Cerebral Infarction↗

PubMed1994

Involvement of high-affinity binding site for EGF receptor in formation of rounding in A-431 epidermoid carcinoma cells.

The introduction of a bacterial aminoglycoside phosphotransferase gene (neo gene) into A-431 cells was found to result in disappearance of high-affinity binding sites of the epidermal growth factor receptor (EGFR), probably by affecting the phosphorylation level of the receptors. Using A-431 cells and their neo gene-transfectants, we studied the relation between "rounding" and the high-affinity sites for EGF; and we also examined the role of protein kinase C (PKC) and A (PKA) in the EGF-induced cell rounding. Pretreatment of A-431 and their transfectant cells with 12-O-tetradecanoylphorbol 13-acetate (TPA; 100 ng/ml), an activator of PKC, for 30 min inhibited both the EGF-induced cell rounding and expression of high-affinity binding sites for EGF. However, both of these responses were recovered when cells were pretreated with TPA for 20 h, which treatment is known to result in depletion of PKC by a process called "down regulation". A similar recovery was also observed when cells were pretreated with forskolin (100 microM), an activator of PKA, for 30 min. Both cell rounding and EGFR high-affinity binding sites disappeared by activation of PKC, and reappeared by activation of PKA. These results suggest that the rounding of A-431 cells by EGF was induced via the high-affinity binding sites of EGFR.

Binding Sites↗

PubMed1994

[Histological and radiobiological study on adult cases with ataxia telangiectasia].

Ataxia telangiectasia (AT) is a hereditary disease that involves both the immune and nervous system; its pathogenesis is believed to be due to disturbances in DNA repair system. Because children are usually affected, reports concerning adult patients are rare. In the present study, we performed comprehensive clinical, histological, and radiobiological examinations on two adult female siblings, currently 23 and 19 years old. The initial symptom was an ataxic gait, which began in the elder sister at the age of 20 and the younger sister at the age of 18. Both had mild telangiectasia in the bulbar conjunctiva and auricula. The neurological manifestations of both were gaze nystagmus, cerebellar ataxia, hyporeflexia, and vibratory sensation disturbance. Only the elder sister showed stocking type sensory disturbance. The MRI of both patients revealed cerebellar atrophy, especially in vermis. After either X-ray irradiation or bleomycin treatment, fibroblast survival curve showed a marked, dose-dependent declined in both patients compared with normal controls. Similar patterns were observed in both patients. After bleomycin treatment, no differences in the survival ratio of cultured fibroblasts could be found between these adult patients and those observed in younger children with classic AT. Biopsied sural nerves showed a decrease in the number of large myelinated fibers, with a few myelinated axons having relatively thin myelin. There were severe atrophic changes, with regenerative myelinated fibers in the elder sister. In conclusion, both adult patients with delayed onset AT displayed similar bleomycin hypersensitivity in fibroblasts as would be expected in children with AT. Radiobiological examinations and sural nerve biopsy suggest that both disturbed cellular regeneration and atrophic process may play a role in the neural involvement in this disease.

Adult↗

PubMed1994

[A case of isolated vagus nerve palsy with herpes zoster].

A case of isolated vagus nerve palsy with herpes zoster was reported. A 31-year-old woman was admitted to our hospital with six days' history of difficulty of swallowing of fluid and hoarseness with a painful vesicle on the right ear. Neurological examination revealed poor elevation of soft palate on the right side, but the pharyngeal reflex was preserved. Herpetic vesicles were present on the right concha, within posterior wall of the external auditory meatus. No facial palsy, loss of hearing and mucosal lesions in the mouth or pharynx were present. This is the first case of isolated vagus nerve palsy due to varicella-zoster infection, showing the distribution of the auricular branch of the vagus (Arnold's nerve) in the ear.

Adult↗

PubMed1993

[Plasma lipoprotein(a) levels in patients with hyperthyroidism].

Recently lipoprotein(a) [Lp(a)], which is an atherogenic giant lipoprotein, has been proved to be a major independent risk factor in cardiovascular and cerebrovascular diseases. Therefore, it is important to study the clinical role of the reduction of plasma Lp(a) in atherosclerosis prevention. In this study we examined the role of plasma Lp(a) levels in patients with hyperthyroidism (HT) in which is commonly observed low levels of total and LDL cholesterol. Plasma Lp(a) levels in 6 men and 17 women aged 17 to 67 (mean 36) years with HT ranged from 0.1 to 17.8 (mean +/- SE; 5.3 +/- 1.0) mg/dl. Those of 36 healthy men and 69 healthy women aged 15 to 73 (mean 41) years ranged from 0.2 to 30.2 (10.7 +/- 0.7)mg/dl, and those of 9 men and 26 women aged 17 to 68 (mean 41) years with HT during treatment more than 6 months ranged from 3.6 to 45.7 (11.1 +/- 1.6)mg/dl. The mean values for Lp(a) in HT were significantly lower than those of the healthy subjects (p < 0.001) or HT during treatment (p < 0.025). Those low levels of Lp(a) in patients with HT were normalized after the appropriate treatment (8.9 +/- 1.4 mg/dl, p < 0.05). A significant correlation was noted between the changes of plasma Lp(a) and LDL cholesterol levels in HT before and after treatment (r = 0.62, p < 0.05). In conclusion, we found that plasma Lp(a) was lowered in patients with HT, and those lowered levels were normalized after treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1993

Parkinson-like symptoms as a manifestation of systemic lupus erythematosus.

A 42-year-old Japanese woman with systemic lupus erythematosus (SLE) developed Parkinsonian-like movements. Steroid pulse therapy was most effective and additional anti-Parkinsonian drugs were not required. Although psychosis, seizures and meningitis are common central nervous system (CNS) manifestations in SLE patients, Parkinsonian-like symptoms are extremely rare. The putative genesis and treatment of CNS lupus are discussed.

Adult↗

PubMed1993

Immunochemical detection of advanced glycation end products in renal cortex from STZ-induced diabetic rat.

To reassess the accumulation of advanced glycation end products in diabetic renal cortex, we used a newly developed enzyme-linked immunosorbent assay to measure AGEs in renal cortex from STZ-induced diabetic and age-matched control rats. Kidneys and aortas were obtained from rats after 5 and 20 wk of STZ injection. At 5 wk of diabetes, the mean AGE content in collagenase-digested materials of renal cortex was > 16-fold higher in diabetic animals compared with controls (1044.4 +/- 151.8 vs. 64.3 +/- 5.7 arbitrary units, P < 0.01). At 20 wk of diabetes, it was > 45-fold higher in diabetic compared with control animals (3841.0 +/- 1077.3 vs. 83.8 +/- 12.8 AUs, P < 0.01). These increases were surprisingly large compared with the < 1.5-fold increase in the fluorescence levels both after 5 and 20 wk of diabetes. In control animals, neither the AGE content nor the fluorescence level increased during this period. Moreover, at 20 wk of diabetes, the AGE content was 39-fold higher in renal cortex compared with aorta. This study provided the first immunochemical evidence that collagenase-digested materials of renal cortex, as well as aorta, contained AGE products and that these products were present in much higher levels in diabetic animals than in control animals. With duration of diabetes, the AGE contents increased significantly both in renal cortex and aorta. The excessive accumulation of AGEs was most apparent in the diabetic kidney.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1993

Evaluation of superoxide scavenging activities of hamamelis extract and hamamelitannin.

Hamamelitannin, which is a component of bark extract of hamamelis (Hamamelis virginior L.), was found to be a potent scavenger of superoxide anion radicals. Superoxide anion scavenging activity of the compound was evaluated by ESR-spin trap method using DMPO (5,5'-dimethyl-1-pyrroline-N-oxide) as a spin trapping agent. The IC50 value (the concentration producing 50% inhibition of superoxide anion radicals) of hamamelitannin was found to be 1.38 +/- 0.06 microM much lower than that of ascorbic acid (23.31 +/- 2.23 microM). Supporting the superoxide scavenging activity of hamamelitannin, the compound showed both suppressive ability against depolymelization of hyaluronic acid and protective ability against cytotoxicity induced by superoxide anion radicals. Hamamelitannin increased the survival rate of fibroblast to 85.5 +/- 3.3%, compared with that of control (27.2 +/- 4.3%).

Ascorbic Acid↗

PubMed1993

[Benign isolated angiitis of the central nervous system predominantly involving veins].

We reported a 58-year-old woman with isolated angiitis of the central nervous system. The patient had suffered from recurrent injection in the left conjunctiva and edema in the left eyelid for three months. Head CT and MRI disclosed a left temporal mass. Carotid angiogram showed left carotid-cavernous fistula, but other vessels were in all normal shape. At biopsy, lymphocyte infiltrations and thickening in entire vessel walls, especially of veins, were found. There was no giant cell or granuloma. The left temporal mass seemed to be caused by venous infarction. Her symptoms disappeared in two weeks after admission without any medication.

Arteriovenous Fistula↗