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971.
Naomi Omi Taro Maruyama Yutaka Suzuki Ikuko Ezawa 《Journal of bone and mineral metabolism》1998,16(4):250-258
A long-term investigation of bone metabolism was conducted in a newly developed strain, the OLETF (Otsuka Long-Evans Tokushima
fatty strain) rat, which spontaneously develops non-insulin-dependent diabetes (NIDDM). The OLETF rats used in this study
developed hyperglycemia before the age of 24 weeks and overt diabetes before 40 weeks. The bone mineral density (BMD) of the
lumbar spine peaked at the age of 24 weeks in the OLETF rats, and declined rapidly after 40 weeks. In addition, the BMD of
the tibial proximal metaphysis and diaphysis and the bone strength of the femoral diaphysis peaked at 40 weeks, then declined
rapidly. In contrast, the BMD and the bone strength of the LETO (Long-Evans Tokushima Otsuka) rats, used as a control, peaked
at 24 weeks, and did not change thereafter. The serum vitamin D metabolites [25-hydroxy vitamin D (25-OHD), 24,25-dihydroxyvitamin
D (24,25(OH)2D), and 1,25-dihydroxy vitamin D (1,25(OH)2D)] levels for the OLETF rats declined with age, and were significantly lower than those of the control LETO rats. The level
of serum bone-specific alkaline phosphatase (Alp) activity and serum tartrate-resistant acid phosphatase (Tr-Acp) activity
in the OLETF rats increased remarkably with age from 24 weeks, and there were significant differences in the 56- and the 69-week
values between the OLETF rats and the age-matched control LETO rats. These results suggested that this strain can serve as
a useful model for NIDDM with osteopenia.
Received: Dec. 12, 1997/Accepted: April 14, 1998 相似文献
972.
Hirohisa Ishimaru Koichi Ishikawa Yoshihide Ohe Akira Takahashi Yuji Maruyama 《Brain research》1996,709(2):155
The distribution patterns of cystatin C and apolipoprotein E (apo E) were studied immunocytochemically in the gerbil hippocampus before and after 5 min ischemia. In the controls, cystatin C was distributed mainly in astrocytes. In addition, a large number of dots positive for cystatin C were observed around the outlines of neuronal perikarya in the CA1 subfields. One day after ischemia, cystatin C-positive stainings outlining neuronal cell bodies disappeared. On the fourth day, intense stainings for cystatin C appeared in atrophied pyramidal neurons and these stainings in neurons disappeared by the 14th day. A remarkable increase in the number of cystatin C-positive astrocytes occurred on the fourth day and thereafter these spread over the whole of the CA1 subfield. Apo E was also distributed in astrocytes in the control specimens. From the fourth day, extra- and/or intracellular distribution of apo E-immunoreactivities was noted in the stratum pyramidale. Apo E-positive astrocytes disappeared transiently on the fourth day and then reappeared and increased remarkably by the 14th day. These findings indicate that cystatin C and apo E are involved in the degeneration process of brain neuronal cells. 相似文献
973.
M Nishimura H Takahashi K Maruyama K Ohtsuka A Nanbu K Hara M Yoshimura 《American journal of kidney diseases》1998,31(5):809-817
To investigate the possible involvement of endogenous nitric oxide (NO) in acute hypotension during maintenance hemodialysis, we measured the plasma concentration of the nitrate anion NO3-, a stable metabolite of NO, in 19 patients undergoing hemodialysis. We analyzed heart rate variability to estimate the relationship between autonomic nervous activity and NO production, low-frequency/high-frequency components (L/H) as a parameter of cardiac sympathetic activity, and high-frequency power as a parameter of cardiac vagal activity. Six patients developed severe hypotension (a change in mean blood pressure during dialysis > or = 20 mm Hg), four patients developed mild hypotension (a change in mean blood pressure < or = 19 mm Hg and > or = 1 mm Hg), and nine patients did not develop hypotension. The plasma levels of NO3- before dialysis were markedly elevated in the severely hypotensive group compared with the patients who showed no hypotension (566+/-122 micromol/L v 133+/-38 micromol/L; P < 0.01), and this difference disappeared midhemodialysis and after hemodialysis. The plasma concentration of NO3- before dialysis was significantly associated with both the change in mean blood pressure during dialysis (r= -0.735; P = 0.003) and the mean blood pressure after dialysis (r = -0.675; P = 0.0015). The L/H ratio was inhibited before or after dialysis in the severely hypotensive group compared with the nonhypotensive group, and hypotension during dialysis was correlated with the inhibited L/H ratio before (r = 0.784; P = 0.001) or after (r = 0.822; P = 0.001) dialysis. Plasma NO3- concentrations were correlated with the L/H ratio before (r = -0.553; P = .014) or after (r = -0.546; P = 0.015) dialysis. These results suggest that inhibited sympathetic activity is one of the causes of acute hypotension during dialysis, and the enhanced production of NO is involved in this inhibition of the sympathetic activity in patients having a hypotensive episode during dialysis. The plasma concentration of NO3- before dialysis may be a predictor of the risk of hypotension during dialysis in patients with end-stage renal disease. 相似文献
974.
Misuzu Maruyama Shunji Miyauchi Hisashi Ohtsuka Yoshiharu Miki 《The Journal of dermatology》1995,22(3):218-222
An 89-year-old woman presented a rapidly growing red nodule of 5 years' duration on her left eyelid. Histologically, the entire dermis was occupied by multiple lobules of atypical tumor cell nests surrounded by inflammatory cells and fibrous stroma. The tumor cell nests were connected with the overlying epidermis and extended into the subcutaneous fat and muscles. There were no tendencies towards squamous or glandular differentiation of the tumor cells. Immunohistochemistry showed the tumor cells to be positive for keratin/cytokeratin and epithelial membrane antigen, but negative for neuron specific enolase and vasoactive intestinal polypeptide. S-100 protein-positive Langerhans cells were also found within the tumor nests. There was no apparent evidence of a primary lesion elsewhere. 相似文献
975.
W. Maruyama D. Nakahara P. Dostert A. Takahashi M. Naoi 《Journal of neural transmission (Vienna, Austria : 1996)》1993,94(2):91-102
Summary Naturally occurring isoquinolines affected the monoamine metabolism in the rat striatum, as proved by in vivo microdialysis technique. By analysis of monoamines and their metabolites in the dialysate, dopamine-derived 6,7-dihydroxy-1,2,3,4-tetrahydroisoquinolines were found to inhibit monoamine oxidase and catechol-O-methyltransferase activity. 1-Methyl- and 2-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline were found to inhibit activity of type A monoamine oxidase most markedly. To compare the structure-activity relationship, corresponding isoquinolines without a catechol structure were also examined. The inhibition by catechol isoquinolines was more manifest than those without a catechol structure. Among latter isoquinolines, N-methyl-isoquinolinium ion was the most potent inhibitor of monoamine oxidase. In addition, catechol isoquinolines increased monoamine levels in the brain. The number and the site of the methyl group are essentially required for the inhibition of monoamine oxidase and a catechol structure for that of catechol-O-methyl-transferase. These results are discussed in relation to possible involvement of these isoquinolines to the clinical features of some neuro-psychiatric diseases, such as alcoholism or in L-DOPA therapy. 相似文献
976.
Yuji Maruyama Shigeo Yamauchi Hajime Imura Shunichiro Sakamoto Masami Ochi Kazuo Shimizu 《Annals of thoracic and cardiovascular surgery》2008,14(2):129-132
We report a case of nonocclusive mesenteric ischemia (NOMI), which developed after grafting for a descending thoracic aortic aneurysm in a hemodialysis patient. On postoperative day 5, acute increases in serum enzyme levels developed. Emergency angiography revealed severe vasoconstriction in the superior mesenteric artery (SMA) and other splanchnic arteries. Therefore an infusion of papaverine hydrochloride was started into the SMA. Although serum enzyme levels decreased, metabolic acidosis occurred the next day. An emergency laparotomy revealed segmental diffuse necrotic small intestine and colon. Despite a resection of the small intestine and sigmoid colon, the patient died of septic shock several days later. NOMI is uncommon, but it is a catastrophic event that can occur after cardiovascular surgery. If intestinal gangrene is suspected, prompt mesenteric angiography and vasodilator therapy followed by exploratory laparotomy should be performed without delay. 相似文献
977.
978.
979.
980.
Study of the use of the microwave magnetic field for the rapid inactivation of brain enzymes 总被引:2,自引:0,他引:2
A new model of a microwave device was developed with a power of 10 kW at 2450 MHz. In order to accomplish even distribution of heating with minimum trauma and with a maximum certainty about enzyme inactivation, a modified magnetic field distribution was utilized rather than the conventional electric field. An integrated tuning system was used to increase efficiency and distribution of microwave energy absorption. This increased the ability of the instrument to properly inactivate the enzymes in the brain of both mice and large rats. In general, the time of irradiation for the rat was 600 to 900 msec and for the mice, 100 to 330 msec. The animal chambers used were designed so as not to impair breathing or too severely restrict movement. The effects of these improvements on microwave irradiation were confirmed by 1) observation of brain appearance, 2) effects on succinic dehydrogenase and cholinesterase activity, 3) measurement of regional temperatures in the animal's brain, 4) thermograms of the brain, 5) electron microscopic examination of brain tissue and 6) measurement of endogenous acetylcholine and catecholamines. 相似文献