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51.
Yasunori Utsunomiya Toshiyuki Imasawa Aya Abe Keita Hirano Tetsuya Kawamura Ryuji Nagasawa Tetsuya Mitarai Naoki Maruyama Osamu Sakai 《Clinical and experimental nephrology》1997,1(2):83-91
Background The purpose of this study was to examine the effects of bacterial suporantigens, which can derange the immune response and
contribute to the renal lesions of immunoglobulin A (lgA) nephropathy.
Methods Twenty-five micrograms of a bacterial superantigen, staphylococcal enterotoxin B (SEB), was injected into IgA nephropathy-prone
ddY mice intrathymically when they reached 6 weeks of age. Evaluation included measurement of albumin excretion in urine,
immunoglobulin concentration, and lymphokine production in vitro, as well as analysis of T-cell receptor expression in splenic
T-cell subsets and examination of renal histology by light and fluorescence microscopy.
Results At 40 weeks of age, the serum level of IgA in these mice was substantially increased and the number of Vβ8+ CD4+splenic T-cells was significantly decreased compared with measurements in untreated controls. Both control and SEB-treated
mice excreted less than 30 μg/mL of urinary albumin. In mice given SEB, the amount of interleukin 2 (IL-2) and tumor necrosis
factor-α (T helper 1 [Th1]-type cytokines) produced by the in vitro-stimulated lymphocytes significantly decreased. whereas
that of interleukin 4 (IL-4) and interleukin 6 (IL-6) (Th2-type cytokines) markedly increased compared with measurements in
control mice. At 40 weeks of age, mice given SEB showed marked glomerular hypercellularity and enhanced glomerular C3 deposition
by renal histology, compared with control mice.
Conclusion These results suggest that bacterial superantigen SEB may modify glomerular lesions through activating Th2 cells, while inducing
deletion of Th1 cells in this experimental model. 相似文献
52.
Giovanni Manfredi Tuan Vu Eduardo Bonilla Eric A. Schon Salvatore DiMauro Enrica Arnaudo Lee Zhang Lewis P. Rowland Michio Hirano 《Annals of neurology》1997,42(2):180-188
We identified large-scale heteroplasmic mitochondrial DNA (mtDNA) rearrangements in a 50–year-old woman with an adult-onset progressive myopathy. The predominant mtDNA abnormality was a 21.2–kb duplicated molecule. In addition, a small population of the corresponding partially deleted 4.6–kb molecule was detected. Skeletal muscle histology revealed fibers that were negative for cytochrome c oxidase (COX) activity and had reduced mtDNA-encoded COX subunits. By single-fiber polymerase chain reaction analysis, COX-negative fibers contained a low number of wild-type or duplicated mtDNA molecules (ie, nondeleted). In situ hybridization demonstrated that the abnormal fibers contained increased amounts of mtDNA compared with normal fibers and that most of the genomes were deleted. We concluded that deleted mtDNA molecules were primarily responsible for the phenotype in this patient. 相似文献
53.
Tsuneo Takebayashi Hiroyuki Obata Yasuhiko Minaki Masatoshi Sekine Kenshi Imoto Kazutoshi Yokogushi Toshihiko Yamashita 《Journal of orthopaedic science》2006,11(3):259-263
Background Cat cry syndrome is an autosomal disease accompanying abnormal deletion of chromosome 5 and occurs in only 1 of 50,000 neonates.
Scoliosis has been reported as a skeletal complication in cat cry syndrome. The characteristics and causes of scoliosis in
this rare syndrome are unknown. The purpose of this study was to present the characteristics of scoliosis in cat cry syndrome
and to speculate on its causative mechanisms.
Methods We report on 11 cases (5 boys and 6 girls) of cat cry syndrome. Detailed investigations of scoliosis, as well as physical
and imaging examinations, were performed to characterize scoliosis and its causes. Average age at initial diagnosis of scoliosis
was 4.3 years, and average age at final examination was 11.8 years.
Results The incidence of scoliosis was as high as 73% (8/11). Most cases show a single right thoracic curve. Of the 8 patients with
scoliosis, 3 patients who had increased muscular tone showed marked progression of scoliosis with growth.
Conclusions Muscular hypertonia may play a key role in the progression of scoliosis in cat cry syndrome. 相似文献
54.
Hidehito Matsuoka Wataru Nishio Toshihiko Sakamoto Hiroaki Harada Noriaki Tsubota 《European journal of cardio-thoracic surgery》2004,26(3):480-482
OBJECTIVE: To predict accurate morbidity after lung resection using treadmill exercise test. METHODS: A total of 130 patients (108 men and 22 women, with mean age 67.1+/-11.4 years (range, 34-78 years)) of 1129 patients underwent standard lobectomy were performed both treadmill exercise test and spirometry preoperatively. We measured maximum oxygen uptake/body weight (VO2max/BW) and change in arterial blood oxygen pressure from rest to symptom-limited maximum loading (delta aPaO2) and calculated exercise-induced hypoxemia (delta PaO2/delta VO2/BW), and retrospectively compared these parameters for patients with and without complications. RESULTS: There were five patients with severe postoperative complications, including three requiring use of a respirator, two with home oxygen therapy. %Vital capacity, VC (%, 80.2+/-13.2 vs. 92.5+/-20.9, P=0.026), delta PaO2 (Torr, -29.3+/-4.3 vs. -13.2+/-10.8, P=0.0004), VO2max/BW (ml/min/kg, 16.5+/-2.9 vs. 20.6+/-5.1, P=0.018) and delta PaO2/delta VO2/BW (Torr/ml/min/kg, -1.98+/-0.26 vs. -0.57+/-0.47) were significantly associated with worse outcome. All the five patients with complications had delta PaO2/delta VO2/BW<-1.7. CONCLUSIONS: Treadmill exercise testing is a good method for assessment of cardiopulmonary reserve. Limited resection must be performed if delta PaO2/delta VO2/BW is under -1.7. 相似文献
55.
Dr. Ichiro Shimoyama Yoshio Nakajima Toshihiko Ito Tadahiko Shibata 《Brain topography》1997,9(4):271-274
Summary We recorded visual evoked potentials (VEPs) elicited with high or low imaginable Chinese characters (HIC or LIC), representing concrete objects or absolute concepts, respectively. A closed circle (CC) acts as control stimulus. These were displayed (at 1.6° visual angle) for 35 ms on a TV monitor. Twenty-one channel VEPs (band-pas filter: 0.05–60 Hz), using balanced non-cephalic electrodes, were recorded from –100 to 924 ms for 11 right-handed male volunteers. The VEPs were analyzed by multivariate analysis of variance (MANOVA) and comparison of topographies at four remarkable peaks (P110, N160, P230 and N320). MANOVA showed significant differences (p< 0.001) for both conditions of channel and stimuli (HIC, LIC or CC). P100 for the CC-VEPs, N160 for the HIC-and LIC-VEPs, P230 for the CC-VEPs, and N320 for the HIC-VEPs were remarkable in the posterior scalp regions. Topographies at P100 and N160 showed no difference between the HIC-and LIC-stimuli. However, those at N320 showed difference between the HIC-and LIC-stimuli over the occipital and posterior temporal areas. Those results suggest that the responses at P100 and N160 might segregate Chinese characters from non Chinese characters. N320 suggested certain processes in imagery on recognizing Chinese characters over the occipital and posterior temporal areas.We are grateful to Dr. Yoshiji Kojima of Hamamatsu University for helpful comments. 相似文献
56.
Papillo-Choledochectomy in the Operative Management of Mucosal Neoplasms of the Periampullary Region
Kogoro Kasahara Ken Saito Yasuo Kondo Toshihiko Yasuda Yoshikazu Yasuda Masatoshi Nakada Hideo Nagai Kyotaro Kanazawa 《HPB surgery》1993,6(3):211-217
Two patients with mucosal cancer of the periampullary region were treated with papillocholedochectomy,
which entails removal of the papilla of Vater and the whole length of the common bile duct. The neoplasm is dissected out through the plane between the duodenal circular and longitudinal muscles, deep to the sphincter of Oddi and the fibromuscular layer of the bile duct. Pathological examination showed that cancer was confined to the mucosal layer without stromal invasion, and that the operation achieved radical cure. For mucosal cancer, papillo-choledochectomy is
an alternative to pancreatoduodenectomy, provided that repeated frozen-section studies confirm the
completeness of excision. 相似文献
57.
Cyclic adenosine monophosphate production and contractile response induced by beta-adrenoceptor subtypes in rabbit urinary bladder smooth muscle 总被引:1,自引:0,他引:1
T Morita S Dohkita S Kondo T Nishimoto S Hirano S Tsuchida 《Urologia internationalis》1990,45(1):10-15
The spontaneous contractile force of muscle strips isolated from male rabbit urinary bladder dome [detrusor) and base (trigonal muscle) was dose dependently inhibited by isoproterenol, a non-specific beta-adrenoceptor agonist. The relaxant response to 10(-6) M isoproterenol in the detrusor muscle was completely blocked by butoxamine (10(-4) M), a selective beta-2-antagonist, and by propranolol (10(-6) M), a non-specific beta-antagonist, but not by metoprolol (10(-6) to 10(-4) M), a selective beta-1-antagonist. Relaxation of trigonal muscle induced by 10(-6) M isoproterenol was inhibited 30% by metoprolol (10(-5) M), 70% by butoxamine (10(-4)M), and 100% by propranolol (10(-6) M). Terbutaline, a selective beta-2-adrenoceptor agonist, also caused dose dependently a relaxant response in detrusor and trigonal muscle. The maximum relaxant responses to isoproterenol and terbutaline were significantly greater in detrusor than in trigonal muscle. Dobutamine, a relatively specific beta-1-adrenoceptor agonist, caused a small but significant relaxant response in trigonal, but no change in detrusor muscle. In trigonal muscle the relaxant response to dobutamine was less than that to terbutaline. Cyclic adenosine monophosphate accumulation in detrusor did not significantly increase after administration of dobutamine, but significantly increased after administration of terbutaline. On the other hand, not only terbutaline, but also dobutamine, markedly increased cyclic adenosine monophosphate accumulation in trigonal muscle.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
58.
We investigated the effects of ultraviolet B (UVB) irradiation on the formation of ester forms of riboflavin and of high-molecular-weight (HMW) protein aggregates and on lenticular riboflavin-binding capacity (LRBC). Esterification of riboflavin decreased as the duration of UV irradiation increased, suggesting the irradiation-induced denaturation of the apoenzyme of synthetases of ester forms of riboflavin. UVB irradiation of lens homogenate supplemented with riboflavin increased LRBC and the formation of HMW protein aggregates, while gamma-crystallin was decreased. These results are consistent with those of our earlier studies in which we obtained data suggesting that, upon exposure of rat lens homogenate to fluorescent light, photosensitized riboflavin may bring about cross-linking of lens protein. Our data demonstrate that the photosensitivity of lenticular riboflavin is increased by longer periods of UV irradiation. 相似文献
59.
Summary In an autopsied case of a 37-year-old man with acquired immune deficiency syndrome (AIDS), multinucleated giant cell encephalopathy was noted in close proximity to multiple nodules of primary lymphoma of the brain. Some multinucleated giant cells and macrophages contained HTLV-III-like viral particles. Nuclear bridges, thin strands connecting individual nuclei with one another, were observed with both light and electron microscopes within some of the multinucleated giant cells. There were also thin tapering nuclear processes, which were probably part of nuclear bridges. The possibility that the nuclear bridges and processes represent amitotic nuclear division is discussed. 相似文献
60.
The metabolism of cadmium oxide (CdO, insoluble form) and cadmium chloride (CdCl2, soluble form) instilled intratracheally into the rat lung was investigated. CdO might be solubilized rapidly in the lung and consequently pulmonary clearance rate of CdO was not so different from that of CdCl2. At a dose of 5 micrograms Cd/rat about 20% of the dose was translocated to the liver within 12 h, whereas gradual and consistent accumulation of Cd was observed in the kidney up to 7 days. Both pulmonary clearance and translocation of Cd to the liver were accelerated with the dose of instilled CdO, however, Cd accumulated in the kidney was proportional to the dose. Lung weight was increased by the instillation of CdO. Lung essential elements such as S, P, Mg, Zn and Mn were not affected in the inflammatory-reparative proliferative process, but Cu content of unit lung weight was slightly decreased. 相似文献