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41.
42.
Role of macrophage and smooth muscle cell apoptosis in association with oxidized low-density lipoprotein in the atherosclerotic development. 总被引:5,自引:0,他引:5
Yuri Akishima Yoshikiyo Akasaka Yukio Ishikawa Zhang Lijun Hideko Kiguchi Kinji Ito Hiroyuki Itabe Toshiharu Ishii 《Modern pathology》2005,18(3):365-373
To examine the role of the apoptosis of macrophages and smooth muscle cells in the development of atherosclerosis, human aortic tissues with intimal lesions were immunostained with antibodies against terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end labeling (TUNEL), single-stranded DNA (clone F7-26), and active caspase-3. Apoptotic cells were detected in the intima using both TUNEL and single-stranded DNA, however, the latter method was the more sensitive one for detecting apoptotic cells in the early stages of atherosclerosis. The number of apoptotic cells increased as the disease progressed. It implies that the apoptosis of intimal cells is involved in the formation of atherosclerotic lesions. In addition, quantitative analyses of the cell types undergoing apoptosis using double-immunostaining revealed that the susceptibility of macrophages and smooth muscle cells to apoptosis was greater specifically in atheroma than in the other atherosclerotic lesions, and macrophages were more susceptible to apoptosis than smooth muscle cells. The frequency and spatial distribution of oxidized low-density lipoprotein (oxLDL) (FOH1a/DLH3)-positive cells were examined by immunohistochemistry, and the results resembled those of apoptotic cells. The number of oxLDL-positive cells in the intima significantly correlated with the susceptibility of smooth muscle cells, but not with that of macrophages, to apoptosis. These results suggest that oxLDL affects the apoptosis of smooth muscle cells during the atherosclerotic development. 相似文献
43.
S Higano S Takahashi K Ishii K Matsumoto H Ikeda K Sakamoto 《AJNR. American journal of neuroradiology》1994,15(8):1435
PURPOSETo describe MR and CT features of germinoma originating in the basal ganglia and thalamus and to discuss the roles of each modality for its diagnosis.METHODSMR and CT studies of six cases of germinomas, five of which were histologically proved, were retrospectively reviewed. T1-weighted, T2-weighted, and contrast-enhanced T1-weighted conventional spin-echo images, and unenhanced and contrast-enhanced CT images were evaluated.RESULTSTypically, the tumor consisted of an irregular solid area with contrast enhancement and various-size cysts. Cystic components were found in five cases and calcification in four. Intratumoral hemorrhage was noted in one. Ipsilateral cerebral hemiatrophy and brain stem hemiatrophy were noted in three cases each. MR was superior to CT in evaluating precise tumor extension, cystic components, and intratumoral hemorrhage, although in one case, extension of the tumor was better defined on CT in its early stage. Calcification was difficult to identify by MR alone. The solid components of the tumors generally showed slightly high density on CT, which seemed to be characteristic compared with nonspecific intensity pattern on MR.CONCLUSIONThe combination of CT and MR findings allows early detection and appropriate diagnosis of the mass in the basal ganglia and/or thalamus. 相似文献
44.
A case of a 43-year-old man with coexistence of intracranial and spinal cavernous angiomas is presented. The patient had a 2-year history of severe back pain incurred by neck flexion, and he became aware of weakness of the right lower extremity and paresthesia of the left lower extremity. Neurological examinations at the time of the first admission demonstrated incomplete Brown-Séquard syndrome. Myelograph, myelo-CT and contrast enhanced CT showed an intramedullary mass at the Th3-Th5 level. The patient received laminectomy with total removal of the lesion. Pathological diagnosis was cavernous angioma. Six years later, the patient complained of subacute weakness and numbness of the left upper extremity. Head CT demonstrated a high density lesion of about 2cm in diameter in the right frontal lobe. MRI showed a mixed signal intensity lesion with a marked low-intensity rim in the same area. Total extirpation of the lesion was performed. Pathological diagnosis of the intracerebral lesion was also cavernous angioma. Intramedullary cavernous angioma is very rare. Furthermore, bifocal cavernous angiomas involving both the spinal cord and the brain are extremely rare, and, only 5 cases have been reported in the literature. To our knowledge, this is the first case diagnosed by surgical specimens of coexisting intramedullary and intracerebral lesions. 相似文献
45.
The effect of diazepam on inbred mutant E1 mice, which develop convulsive seizures after repeated sessions of being tossed up, was examined. Acute administration of diazepam (32 mg/kg, i.p.) completely inhibited the convulsions. At that time, the dopamine level was increased in the cortex and hippocampus, and the norepinephrine level in the cerebellum was decreased. 5-Hydroxytryptamine levels were not changed. As for amino acids, the glutamine level increased and the levels of GABA, glutamic acid, aspartic acid, alanine and other amino acids were not changed. 相似文献
46.
K Sawada H Yamamoto K Matsumoto H Yago S Suehiro C Tahara H Ishii M Kazama T Abe 《Thrombosis research》1992,65(2):199-209
Changes in the plasma thrombomodulin (TM) level were examined in endotoxin-infused rabbits. The plasma TM level in normal rabbits was 143.8 +/- 8.4 ng/ml (n = 67) and the molecular weight of the major TM was about 55 kd. Endotoxin (lipopolysaccharide, LPS, E. Coli B8:0127) was intravenously infused. LPS infusion increased the plasma TM level dose-dependently between 0.2 mg/kg and 5 mg/kg. When 5 mg/kg LPS was infused, the plasma TM level started to increase immediately and was 2.3 times higher than the control value within 1 hr. The molecular weight of the major TM was about 75 kd. This rapid increase in TM occurred before the decrease in fibrinogen content and the prolongation of prothrombin time. To examine the effect of circulating leukocytes on the TM increase in endotoxin-infused rabbits, 5 mg/kg LPS was infused into rabbits with leukocytopenia induced by X-ray irradiation. The maximum plasma level of TM was significantly lower than in the untreated rabbits given LPS. These data suggest that the increase in plasma TM is caused by LPS-stimulated leukocyte's prior to hemostaseological changes. It is well known that endothelial cells can be injured by stimulated leukocytes, so this increase in plasma TM probably reflects the deterioration of endothelial cells. This deterioration decreases the ability of endothelial cells to inhibit thrombosis, which would, in turn, contribute to the development of disseminated intravascular coagulation in endotoxin-infused rabbits. 相似文献
47.
Yoshikiyo Akasaka MD PhD ; Kinji Ito PhD ; Kazuko Fujita PhD ; Kazuo Komiyama DDS ; Ichiro Ono MD PhD ; Yukio Ishikawa MD PhD ; Yuri Akishima MD PhD ; Hiroko Sato MD PhD ; Toshiharu Ishii MD PhD 《Wound repair and regeneration》2005,13(4):373-382
To characterize apoptosis in keloids and the mechanisms responsible for this process, the expression of activated caspase-9 and -3 in fibroblasts obtained from keloids was analyzed. Immunohistochemistry revealed that the number of fibroblasts positive for terminal deoxynucleotide transferase-mediated dUTP nick-end labeling (TUNEL) or activated caspase-9 or -3 was low but was significantly higher in keloid tissues than in normal scar tissues. Significant relationships between the number of caspase-positive fibroblasts and TUNEL-positive fibroblasts suggested that the activation of caspase-9 and -3 induces apoptosis in a subpopulation of keloid fibroblasts. All keloid fibroblast cell lines established in this study showed activation of caspase-9 and -3 after serum deprivation for 3 or 4 hours, as shown using Western blotting. Furthermore, serum deprivation-induced apoptosis in a keloid fibroblast line was blocked by a caspase-9 inhibitor (acetyl-Leu-Glu-His-Asp-al), indicating that activation of caspase-9 was necessary for the process of apoptosis in keloid fibroblasts. Although serum deprivation did not significantly change the level of apoptosis protease activating factor-1 in any of the lines, cytochrome c release was detected in cytosolic fractions of the lines after serum deprivation for 3 or 4 hours. These results strongly suggest that keloid fibroblasts are predisposed to apoptosis and cytochrome c release and that caspase-9 activation may underlie regulation of apoptosis in keloid fibroblasts in vivo. 相似文献
48.
Seventeen specimens of orbital fatty tissue taken from cases of dysthyroid ophthalmopathy at the time of operation were observed by light and electron microscopy, and also by immunohistochemical staining. The pathological changes observed were infiltration of the chronic inflammatory cells, deposit of fibrin, sclerosis of vascular wall, occlusion of the vascular lumen, and accumulation of hydrophilic mucopolysaccharide. Immunoglobulin G was detected in fat cells and lymphocytes, and some of the infiltrating lymphocytes were determined to be T cells, by immunohistochemistry. These findings suggested that the pathology of the dysthyroid ophthalmopathy was closely related to the chronic inflammation induced by the immune reaction. The exophthalmos was considered to occur due to edema secondary to chronic inflammation and accumulation of the mucopolysaccharides. 相似文献
49.
Chien-Huang Lin Feng-Nien Ko Hisahi Ishii Tsutomu Ishikawa Ih-Sheng Chen Che-Ming Teng H.-P. Kuo 《Naunyn-Schmiedeberg's archives of pharmacology》1997,355(2):210-216
We investigated the effects of a novel platelet-activating factor (PAF) receptor antagonist, CIS-19 [cis-2-(3, 4-dimethoxyphenyl)-6-isopropoxy-7-methoxy-1-(N-methylformamido)-1,
2, 3, 4-tetrahydronaphthalene], on PAF-, histamine-, substance P- and antigen-induced bronchoconstriction and microvascular
leakage, as well as PAF- and antigen-induced bronchial hyperreactivity to methacholine in urethane-anesthetized guinea-pigs.
Administration of CIS-19 (0.5–5 mg/kg, i.v.) inhibited the increase in lung resistance induced by PAF (30 ng/kg, i.v.) in
a dose-dependent manner, but failed to inhibit the increase induced by histamine (30 μg/kg, i.v.) or substance P (6.5 μg/kg,
i.v.). CIS-19 (5 mg/kg, i.v.) did not inhibit the increase in lung resistance induced by ovalbumin (2 mg/kg, i.v.) in actively
sensitized guinea-pigs. PAF (30 ng/kg, i.v.)-induced microvascular leakage, measured by the extravasation of Evans blue dye,
was dose-dependently inhibited by CIS-19 (0.5–5 mg/kg, i.v.) in the trachea, main bronchi and intrapulmonary airways, but
it did not affect histamine (30 μg/kg, i.v.)- or substance P (6.5 μg/kg, i.v.)-induced microvascular leakage at all airway
levels. CIS-19 (2.5 and 5 mg/kg) did not affect ovalbumin (2 mg/kg, i.v.)-induced microvascular leakage in all airway levels
in actively sensitized guinea-pigs. CIS-19 (2.5 and 5 mg/kg, i.v.) significantly inhibited PAF-induced enhancement of the
bronchial response to methacholine, but had no effect on ovalbumin (0.05 mg/kg, i.v.)-induced bronchial hyperreactivity in
actively sensitized guinea-pigs. It is concluded that CIS-19 is a potent PAF receptor antagonist which inhibits PAF- but not
antigen-induced bronchoconstriction, microvascular leakage and bronchial hyperreactivity. These results suggest that PAF plays
little or no role in early airway responses following antigen challenge.
Received: 29 April 1996 / Accepted: 10 October 1996 相似文献
50.
H Kishimoto O Takazu S Ohno T Yamaguchi H Fujita H Kuwahara T Ishii M Matsushita S Yokoi M Iio 《Psychiatry research》1987,22(1):81-88
The authors used positron emission tomography (PET) and 11C-labeled glucose to study 15 unmedicated patients with affective disorders and 7 control subjects. Diagnoses of affective disorders were based on DSM-III criteria, and symptomatology was evaluated by the Hamilton Rating Scale for Depression. Blood counts of 11C in both unipolar and bipolar patients did not differ from those in controls after oral administration of 11C-glucose. By contrast, brain counts of 11C in unipolar depressed patients were significantly lower, whereas those in bipolar manic patients were significantly higher, than in normal controls. 相似文献