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21.
Kunio Ii Hidehumi Ito Eiki Kominami Asao Hirano 《Virchows Archiv : an international journal of pathology》1993,423(3):185-194
The immunolocalization of cathepsins B(CB), H and L and cystatins(C) and(C) were examined in the hippocampus of cases of sporadic Alzheimer's disease (12 cases), parkinsonism-dementia complex on Guam (eight cases), senile dementia of Alzheimer type (two cases), aged subjects with marked senile change (one case) and controls (12 cases, including six normal subjects). CB was lower in most nerve cells in patients than in controls, but markedly increased at the sites of intracellular neurofibrillary tangles (NFTs) and degenerative neurites and/or dendrites in and outside senile plaques (SPs), indicating its close involvement in the metabolisms of various proteins in NFT and SPs. Abundant C and C were demonstrated in SP amyloid, suggesting that they are amyloid constituents or co-exist with amyloid. The present study indicated that CB, C and C are closely involved in abnormal protein metabolism in NFTs and SP amyloid and suggested that degeneration or denaturation of intracellular proteins, including substrates for proteases and lysosomes, from some acquired cause, results in absolute and/or relative overload for these proteolytic systems, including their inhibitors. This results in incomplete and/or abnormal proteolysis related to NFT and/or amyloid formation. 相似文献
22.
Satoshi Muraki Masahiro Yamasaki Kojiro Ishii Kunio Kikuchi Kunihiro Seki 《European journal of applied physiology》1996,72(4):330-334
The purposes of the present study were to examine the response of the skin blood flux (SBF) in the paralyzed lower limbs of persons with spinal cord injury (PSCI) and to clarify the relationship between the SBF and core temperature during prolonged arm exercise. Eight male PSCI with lesions from T6 to L5 and six male control subjects (CS) participated in this study. The subjects rested for 60 min and then performed arm-cranking exercise at 20 W for 30 min at 25 °C. The tympanic membrane temperature (T
ty) and SBF in the anterior thigh (SBFT) and in the posterior calf (SBFC) were continuously measured throughout the experiment. The SBFC did not change in either PSCI or CS during the experiment. The SBFT in four PSCI with high lesions (T6 to T12), remained unchanged during exercise. The SBFT in the other four PSCI with low lesions (T12 to L5, SBFT+) began to elevate markedly when the T t, exceeded a threshold temperature of 36.69 °C. The pattern of increase of SBFT in SBFT+ was similar to that in CS, although onset of the increase in SBFT was delayed and the peak of SBFT during exercise was significantly lower in comparison with the CS. We consider that these differences between the SBFT+ and CS were largely attributable to the lowerT
ty in the former group, which took a prolonged time to reach the threshold of 36.69 °C. 相似文献
23.
Adjuvant Activity of 6-Amino-6-Deoxy-Muramyldipeptides and Their Acylamino Derivatives on the Induction of Delayed Hypersensitivity to Azobenzenearsonate-N-Acetyl-l-Tyrosine in Guinea Pigs 下载免费PDF全文
Ichiro Azuma Hiroyuki Okumura Ikuo Saiki Yoshiro Tanio Makoto Kiso Akira Hasegawa Yuichi Yamamura 《Infection and immunity》1981,32(3):1305-1308
The 6-amino-6-deoxy-N-acetylmuramyldipeptides and their 6-acylamino derivatives were shown to be active as adjuvants on the induction of delayed-type hypersensitivity to azobenzenearsonate-N-acetyl-l-tyrosine in guinea pigs. However, 6-acylamino-6-deoxy-N-(acyl)muramyldipeptides were inactive as adjuvants. 相似文献
24.
Keishi Okamoto Kodo Kodama Katsushi Kawai Tetsuaki Wakebe Kazunobu Saiki Seiji Nagashima 《Annals of anatomy》2006,188(1):49-53
Among cases that had multiple renal arteries on one side, an inferior supernumerary renal artery was found in 24/270 cases (ca. 9%) on the right and in 19/270 cases (ca. 7%) on the left, together with the usual renal artery. We have noticed that there are correlations between their levels of origin from the aorta and their positional relation to the ureter and the inferior vena cava (IVC). An inferior supernumerary renal artery (InfRA) of lower origin passes in front of the IVC and behind the ureter. An InfRA of middle origin passes in front of both the IVC and the ureter. An InfRA of upper origin passes behind the IVC and in front of the ureter or renal pelvis. In addition there was a tendency for the lower origin type to have an ureteric branch, while the middle and upper origin types had a gonadal branch. These findings suggest that different derivations lead to the inferior supernumerary renal arteries. 相似文献
25.
Torii K Kimura H Li X Okada T Imura T Furusaki F Ono T Yoshida H 《Rinsho byori. The Japanese journal of clinical pathology》2005,53(3):207-212
Chronic hypoxia has been newly proposed as a common mechanism of tubulointerstitial fibrosis in the progression of various chronic inflammatory renal diseases, where PAI-1 plays an important role in the accumulation of extracellular matrix (ECM) through inhibition of plasmin-dependent ECM degradation. In the present study, we investigated the presence of PAI-1 in renal tubular cells by immunostaining renal biopsy samples. We also closely examined the effects of hypoxia and TNF-alpha on PAI-1 expression in cultured human proximal renal tubular cells (HRCs). Confluent cells growth-arrested in DMEM for 24h were exposed to hypoxia (1% O2) and/or TNF-alpha at 10 ng/ml for 24 hours. Amounts of PAI-1 protein and mRNA after stimulation were measured by ELISA and TaqMan quantitative PCR, respectively and compared to those in cells incubated under control conditions (18% O2 without TNF-alpha). HIF-1alpha was demonstrated by immunoblot analysis. In crescentic glomerulonephritis, clusters of proximal tubules were specifically stained for PAI-1. Treatment of 24 hours with hypoxia, TNF-alpha and their combination induced a 2.7-fold, a 1.8-fold, and a 4.6-fold increase in PAI-1 protein secretion, and produced a 3.6-fold, a 3.3-fold, and a 12.1-fold increase at the PAI-1 mRNA level, respectively. Immunoblot analysis revealed that hypoxia-inducible factor-1alpha (HIF-1alpha) was markedly accumulated in the nuclear fraction after 16-hours exposure of HPTECs to hypoxia but not to TNF-alpha. In conclusion, hypoxia induces PAI-1 expression via remarkable nuclear accumulation of HIF-1alpha in HRCs. TNF-alpha can enhance this hypoxia-induced PAI-1 expression. 相似文献
26.
Rat strain differences in the early stage of porcine-serum-induced hepatic fibrosis. 总被引:1,自引:0,他引:1
Yasuko Baba Koji Uetsuka Hiroyuki Nakayama Kunio Dot 《Experimental and toxicologic pathology》2004,55(5):325-330
Rat strain differences in the early development of porcine serum (PS)-induced hepatic fibrosis were histologically and immunohistochemically examined using Brown Norway (BN), Sprague Dawley (SD) and Wistar rats. They were injected i.p. with 0.5 ml sterile PS twice a week for 4 and 8 weeks. In addition, rats treated with physiological saline in the same way served as controls. At 4 weeks, hepatic fibrosis accompanying fibrous septa mainly composed of type III collagens developed in BN and SD rats but not in Wistar rats. In addition, the numbers of eosinophils, CD3-positive cells and ED-1-positive cells significantly increased in BN and SD rats, that of CD45RA-positive cells in BN rats, and that of alpha-smooth muscle actin (SMA)-positive cells in SD rats, respectively. Such differences in the number of inflammatory cells may be related with the absence of hepatic fibrosis in Wistar rats at 4 weeks. At 8 weeks, hepatic fibrosis with formation of many small-sized pseudolobules was observed in all strains at almost similar degree, and the numbers of infiltrating cells increased in all strains of rats with some exception. In addition, the main location of inflammatory cells was different, suggesting a different role of each inflammatory cell in the process of hepatic fibrosis. 相似文献
27.
Quercetin inhibits the invasion and mobility of murine melanoma B16-BL6 cells through inducing apoptosis via decreasing Bcl-2 expression 总被引:5,自引:0,他引:5
Quercetin has been known to have anti-tumor and anti-oxidation activities. In the present study, we have investigated its
in vitro anti-metastatic activity. Quercetin inhibited the invasion and mobility of murine melanoma B16-BL6 cells in a dose-dependent
manner but did not affect their adhesion to either laminin, fibronectin, or type VI collagen. Moreover, quercetin significantly
inhibited the proliferation of B16-BL6 cells only in the case of time incubation longer than 48 h. Quercetin dose-dependently
decreased the cell rates in S and G2–M phases of cell cycle. The effect of quercetin to cause a remarkable apoptosis of B16-BL6
cells was also demonstrated by flow cytometric assay as well as DNA fragmentation with a typical 180-bp ladder band in agarose
electrophoresis and a quantitative analysis. Furthermore, quercetin markedly inhibited the expression of anti-apoptotic protein
Bcl-2 but hardly influenced Bcl-XL. These results suggest that the inhibition of quercetin on invasiveness and migration of B16-BL6 cells are closely associated
with the arrest of cell cycle as well as the induction of apoptosis by decreasing the Bcl-2 expression.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
28.
IL-8 as an important chemoattractant for neutrophils in ulcerative colitis and Crohn's disease. 总被引:7,自引:2,他引:7 下载免费PDF全文
K Mitsuyama A Toyonaga E Sasaki K Watanabe H Tateishi T Nishiyama T Saiki H Ikeda O Tsuruta K Tanikawa 《Clinical and experimental immunology》1994,96(3):432-436
IL-8 is generating increasing interest as a powerful neutrophil chemoattractant and activator. To elucidate the mechanisms of neutrophil infiltration in inflammatory bowel disease, we examined 33 patients with ulcerative colitis (UC), 18 with Crohn's disease (CD), eight with some other type of colitis, and 18 normal control subjects for measurement of IL-8 in homogenates of colonic biopsy specimens. The affected colonic mucosa was found to contain significantly more IL-8 in patients with active inflammatory bowel disease than in patients with inactive disease (UC, P < 0.001; CD, P < 0.001), in patients with other types of colitis (UC, P < 0.05; CD, P < 0.01), or in normal control subjects (UC, P < 0.001; CD, P < 0.001). Colonic IL-8 levels correlated significantly with the macroscopic grade of local inflammation, especially in patients with UC (P < 0.001). Colonic IL-8 levels also correlated well with the neutrophil numbers in mucosal tissue (UC, r = 0.950, P < 0.001; CD, r = 0.940, P < 0.001), and with colonic IL-1 beta (r = 0.911, P < 0.001) and tumour necrosis factor-alpha (TNF-alpha) levels (r = 0.604, P < 0.001) in patients with these two conditions. These data suggest a potential role for IL-8 and its regulatory cytokines IL-1 and TNF-alpha in mediating neutrophil infiltration of the gut wall in inflammatory bowel disease. 相似文献
29.
Satoshi Muraki Masahiro Yamasaki Yoshito Ehara Kunio Kikuchi Kunihiro Seki 《European journal of applied physiology》1996,74(5):481-483
The purpose of the present study was to examine the effect of maximal arm exercise on the skin blood circulation of the paralyzed
lower limbs in persons with spinal cord injury (PSCI). Eight male PSCI with complete lesions located between T3 and L1 performed
graded maximal arm-cranking exercise (MACE) to exhaustion. The skin blood flux at the thigh (SBFT) and that at the calf (SBFC)
were monitored using laser-Doppler flowmeter at rest and for 15 s immediately after the MACE. The subject's mean peak oxygen
uptake and peak heart rate was 1.41 ± 0.22 l · min–1 and 171.6 ± 19.2 beats · min–1, respectively. No PSCI showed any increase in either SBFT or SBFC after the MACE, when compared with the values at rest.
These results suggest that the blood circulation of the skin in the paralyzed lower limbs in PSCI is unaffected by the MACE.
Accepted: 12 September 1996 相似文献
30.
Clonal differences in response to T cell replacing factor (TRF) for IgM secretion and TRF receptors in a human B lymphoblast cell line 总被引:6,自引:0,他引:6
A number of human B lymphoblast cell lines were tested to find a suitable model for induction of immunoglobulin-secreting cells (ISC) by T cell replacing factor (TRF). Partially purified TRF was size fractionated from the conditioned medium of irradiated (1000 rds) human spleen cells stimulated with pokeweed mitogen. IgM line SKW 6 showed high levels of TRF-stimulated immunoglobulin secretion and was chosen for cloning experiments. Clone 11 had a very low level of ISC with or without TRF (less than 0.1% ISC). Clone 4 had low background numbers of ISC (0.2%) and showed the highest degree of stimulation by TRF (to 6% IFC). High secreting clone 8-2 (6%) was not stimulated significantly by TRF. These clones had the same HLA-DR antigens, and their levels of ISC and sensitivity to TRF were relatively stable over three months of observation. The TRF preparation also had strong helper activity for normal peripheral blood B cell differentiation. TRF activity for both normal B cells and clone 4 cell line was absorbed by all 3 clones, but not by a pre-B line. This suggests that the effector molecules for normal B cell and cell line differentiation were the same. The three typical clones corresponding to nonresponding, responding, and high rate-secreting B cells provide basic models for analyzing B cell receptors for TRF and the biochemical effects of TRF during B cell differ entiation. 相似文献