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M. Iwasa Y. Maeno H. Inoue H. Koyama R. Matoba 《International journal of legal medicine》1996,109(1):23-28
We examined whether methamphetamine (MAP) induced apoptotic cell death in vivo. Male Wistar rats were injected intraperitoneally with 25 mg MAP/Kg body weight and were sacrificed at 4, 8 and 24 h. As early as 4 h after a single dose of MAP, DNA ladder bands representing DNA fragmentation into multiples of the internucleosomal DNA length of about 180 by were observed by gel electrophoresis in thymic and splenic DNA. DNA from control rats injected with 1 ml physiological saline/Kg body weight showed no ladder band patterns. The proportion of fragmented DNA from the thymus increased in a time-dependent manner up to 8 h and faint ladder band patterns were observed at 24 h, indicating that cell death via apoptosis occurred at an early stage and then apoptotic bodies were scavenged. DNA fragmentation in the thymus and spleen induced with MAP was also confirmed by the terminal deoxynucleotidyl transferase-mediated dUTPbiotin nick end labeling (TUNEL) method in situ. In control thymus samples, stained cells were numerous in the cortex but sparse in the medulla. At the boundary area between the cortex and medulla, stained cells were seen as a layer. In the MAP-treated rats, stained cells were increased and dispersed equally in the cortex and medulla. In control spleen samples, stained cells were numerous in all areas excluding the germinal centers. Cells at the germinal centers were stained intensively in MAP-treated rat spleen. Light microscopical analyses allowed us to identify lymphocytes during the course of apoptotic cell death. Electron microscopic studies showed morphological landmarks for the process of cellular apoptosis in both organs e.g. lymphocytes with chromatin condensed into crescents at the periphery of the nuclei and apoptotic bodies. These results indicate that MAP induced cell death of the thymic and splenic lymphocytes via apoptosis. 相似文献
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Joji Ishikawa Satoshi Hoshide Seiichi Shibasaki Yoshio Matsui Tomoyuki Kabutoya Kazuo Eguchi Shizukiyo Ishikawa Thomas G Pickering Kazuyuki Shimada Kazuomi Kario 《Hypertension research》2006,29(3):153-159
Morning blood pressure is reported to be more closely related to hypertensive organ damages such as left ventricular mass index, microalbuminuria and silent cerebral infarcts, than blood pressure at other times of the day. Morning blood pressure may play an important role in the pathogenesis of hypertensive target organ damage. Increased sympathetic nerve activity is reported to be one of the mechanisms of morning hypertension; however, there are no available data that show whether strict home blood pressure control, especially in the morning period, can reduce target organ damage. The Japan Morning Surge-1 (JMS-1) study includes hypertensive outpatients with elevated morning systolic blood pressure (>or=135 mmHg) as assessed by self-measured blood pressure monitoring at home. All enrolled patients are under stable antihypertensive medication status. Exclusion criteria are arrhythmia, chronic inflammatory disease, and taking alpha-blockers or beta-blockers. The target number of patients to be enrolled in the JMS-1 study is 600, and the aim is to evaluate differences in the markers of hypertensive target organ damage, such as brain natriuretic peptide and the urinary albumin excretion/creatinine ratio. All of the patients are randomized to an experimental group or a control group, with randomization to be carried out by telephone interviews with the patients' physicians. In the experimental group, patients begin taking additional antihypertensive medication just before going to bed. This consists of doxazosin 1 mg/day, which then is increased to 2 mg/day and 4 mg/day, with a beta-blocker added after a 1-month interval until the morning systolic blood pressure is controlled to less than 135 mmHg. Patients in the control group continue the treatment they are receiving at the enrollment for 6 months. Blood pressure levels, adverse effects, and hypertensive target organ damage before and after the study are evaluated. In the JMS-1 study, we will evaluate whether strict morning blood pressure control by sympathetic nervous system blockade using an alpha-blocker, doxazosin, and with the addition of a beta-blocker if needed, can reduce hypertensive target organ damage. 相似文献
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S Ogoshi M Iwasa S Kitagawa Y Ohmori S Mizobuchi Y Iwasa T Tamiya 《JPEN. Journal of parenteral and enteral nutrition》1988,12(1):53-57
The effect of a nucleoside-nucleotide mixture on liver injury of rats induced by D-galactosamine was studied by examining changes in function and histopathology of the liver. Animals with liver damage received total parenteral nutrition with glucose and amino acids supplemented with a nucleoside-nucleotide mixture containing inosine, cytidine, GMP, uridine and thymidine, or with uridine which inhibits galactosamine injury, or with liver cell extract containing flavin adenine dinucleotide and nucleic acid derivatives. As control, animals with liver damage received total parenteral nutrition with glucose and amino acids only. The serum GOT and GPT concentrations were significantly lower in the group supplemented with nucleoside-nucleotide mixture than those in other groups. A large dose (1.2 g/kg) of uridine inhibited liver injury, but a lower dose (0.14 g/kg) did not have any effect, whereas nucleoside-nucleotide mixture containing the same amount of uridine inhibited the injury. Liver cell extract also did not improve liver function. Thus infusion of a physiological and balanced mixture of nucleosides or nucleotides may improve liver function in rats with liver injury. 相似文献
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3D kinematic analysis of the acromioclavicular joint during arm abduction using vertically open MRI.
Wataru Sahara Kazuomi Sugamoto Masakazu Murai Hiroyuki Tanaka Hideki Yoshikawa 《Journal of orthopaedic research》2006,24(9):1823-1831
Many researchers have evaluated the motions of the shoulder girdle, especially scapular and humeral motion. However, few reports exist that describe motions of the acromioclavicular joint. The purpose of the present study was to analyze the 3D kinematics of the acromioclavicular joint during arm abduction using 3D MR images obtained by a vertically open MRI. Fourteen shoulders of seven volunteers were examined in seven static positions from 0 degrees to the maximum abduction in a seated position. 3D surface models of the clavicle and scapula were created, and the movements of the acromioclavicular joint from 0 degrees to each position were calculated using the volume-based registration technique. From these calculations, the translations were evaluated and the rotational motions were analyzed using the concept of the screw axis. In the anteroposterior direction, the clavicle translated most posteriorly (-1.9 +/- 1.3 mm) at 90 degrees of abduction and most anteriorly (1.6 +/- 2.7 mm) at maximum abduction. In the superoinferior direction, the clavicle translated slightly superiorly (0.9 +/- 1.9 mm). When analyzing relative motion of the scapula with respect to the clavicle, the scapula generally rotated about a specific screw axis passing through the insertions of both the acromioclavicular and the coracoclavicular ligaments on the coracoid process. The average rotation was 34.9 +/- 8.4 degrees. 相似文献
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Iwasa MA Kariwa H Cui BZ Lokugamage K Lokugamage N Hagiya T Mizutani T Takashima I 《Archives of virology》2004,149(5):929-941
Summary. To elucidate the mode of transmission of Puumala-related hantavirus in a population of gray red-backed voles, Clethrionomys rufocanus bedfordiae, in Hokkaido, Japan, we analyzed the kin structure and dispersal patterns of individual voles using microsatellite and mitochondrial DNA markers. Siblings or dam/offsprings was identified within the population based on the relatedness calculation with the microsatellite data. The pairwise relatedness values obtained could reveal kinship among all vole individuals within the population. Based on the assessment of kinship, we did not find a positive relationship between hantavirus transmission and close kinship. Males infected with the hantavirus carried a relatively uncommon mitochondrial haplotype. However, these infected males shared low relatedness values and were not considered closely related, i.e., they were not siblings or parent/offspring. These observations imply that hantavirus transmission in the vole population may not be related to close kinship but by random horizontal infection. 相似文献
9.
Improved rubella hemagglutination inhibtion test: inactivation of non-immunoglobulin hemagglutination inhibitors by phospholipase C. 下载免费PDF全文
A method using phospholipase C (PL-C) for removing nonspecific inhibitors (NSI) of rubella virus hemagglutinin is described. PL-C was found to hydrolyze NSI without altering the hemagglutination inhibition (HI) activity of the specific antibody and could be used to remove NSI in the rubella HI test by using formalinized erythrocytes, which resisted the enzymatic action; fresh erythrocytes were lysed by PL-C. The HI test using PL-C treated sera gave true measurements of actual rubella antibody content, and HI titers of PL-C treated sera were identical or equivalent (+/-1 dilution) to those of sera treated with dextran sulfate and CaCl2 (DS-C). Thus, the PL-C method gave results as reproducible and reliable as the DS-C method and was more convenient. 相似文献
10.
Nakabo S Torii Y Itota T Ishikawa K Miyazaki K Suzuki K Yoshiyama M 《Biomaterials》2002,23(16):3503-3508
We previously demonstrated that fluoride release from resins could be regulated by the polysiloxane coating of the fluoride additives. The present study investigated the effects of regulated fluoride release from resin on enamel demineralization in vitro. Bovine enamel cavities were restored with bis-GMA/TEGDMA resins containing 50 wt% NaF powders treated with or without gamma-methacryloxypropyltrimethoxysilane. Specimens were immersed in distilled water that was changed daily to measure the amount of fluoride released over 40 days, and thereafter subjected to pH-cycling. Microradiographic observations were performed to determine total mineral loss (AZ) and lesion depth (Ld) on the enamel. In addition, fluorine distribution was analyzed using EPMA. The resin containing untreated NaF exhibited high-rate and short-term fluoride release, whereas the resin containing treated NaF released low concentrations of fluoride over a longer period. The former showed high fluorine uptake in the adjacent enamel. In contrast, the latter showed high fluorine uptake not only in the adjacent enamel, but also in a wider area of enamel surface. The latter also showed lower AZ and Ld values in the surrounding enamel, indicating a high inhibitory effect on caries formation. Therefore, it is suggested that regulated fluoride release from the resin based on polysiloxane coating is effective in preventing caries formation. 相似文献