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91.
Yamamoto Kazuhiko; Nakajima Akira; Eimoto Hiroyuki; Tsutsumi Masahiro; Maruyama Hiroshi; Denda Ayumi; Nii Hiroaki; Mori Yukio; Konishi Yoichi 《Carcinogenesis》1989,10(9):1607-1611
The carcinogenic activity of endogenously synthesized N-nitrosobis(2-hydroxypropyl)amine(BHP) was investigated in male Wistar rats administered bis(2-hydroxypropyl)amine(BHPA) mixed in powder diet at a concentration of 1%, and sodiumnitrite (SN) dissolved in distilled water at concentrationsof 0.15 and 0.3%, for 94 weeks. Urinary excretion of BHP wasdetected in rats given 1% BHPA and 0.3% SN but not in the groupsreceiving either of these precursors alone. Nasal cavity, lung,esophagus, liver and urinary bladder tumors were found in animalstreated with combinations of 1% BHPA and 0.15 or 0.3% SN, suggestingthat the target organs of the endogenously synthesized BHP aresimilar to those affected when the carcinogen is administeredexogenously. The incidences of nasal cavity and lung tumorsreached 74 and 58% in rats given 1% BHPA and 0.3% SN, respectively.Tumors at sites other than target organs were only found atlevels similar to those previously reported for spontaneoustumors in male Wistars. The present results clearly indicatedthe tumor inducibility of a nhrosatable amine, BHA, throughan endogenous nitrosation by feeding to rats in conjunctionwith nitrite, and provide further suggestive evidence that endogenousnitrosations of environmental nitrosatable amines can be a potentialrisk factor in human cancer development. 相似文献
92.
Glyceraldehyde-3-phosphate dehydrogenase: Nuclear translocation participates in neuronal and nonneuronal cell death 下载免费PDF全文
Akira Sawa Adil A. Khan Lynda D. Hester Solomon H. Snyder 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(21):11669-11674
Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) protein levels increase in particulate fractions in association with cell death in HEK293 cells, S49 cells, primary thymocytes, PC12 cells, and primary cerebral cortical neuronal cultures. Subcellular fractionation and immunocytochemistry reveal that this increase primarily reflects nuclear translocation. Nuclear GAPDH is tightly bound, resisting extraction by DNase or salt treatment. Treating primary thymocytes, PC12 cells, and primary cortical neurons with antisense but not sense oligonucleotides to GAPDH prevents cell death. Because cell-death-associated nuclear translocation of GAPDH and antisense protection occur in multiple neuronal and nonneuronal systems, we propose that GAPDH is a general mediator of cell death and uses nuclear translocation as a signaling mechanism. 相似文献
93.
Hiromi Oono Masae Nakagawa Atsushi Miyamoto Shigeru Ishiguro Akira Nishio 《Magnesium research》2002,15(3-4):153-160
We have previously shown that interleukin (IL)-1beta and tumour necrosis factor (TNF)-alpha mRNA levels in rat alveolar macrophages are increased in by endotoxin (lipopolysaccharide; LPS)- stimulation and further enhanced by culturing with low-Mg2+ medium. We have now investigated the mechanisms of underlying this enhancement by using some specific signal transduction inhibitors. The enhanced elevation of both mRNAs levels was suppressed by pretreatment with TMB-8 (which inhibits calcium release from the endoplasmic reticulum) or dexamethasone (which inhibits nuclear factor [NF]-kappaB and activator protein [AP]-1), but not with verapamil or nifedipine (which inhibits calcium channels). The enhancment of IL-1beta, but not TNF-alpha mRNA levels, was suppressed by pretreatment with W-7 (which inhibits calmodulin), whereas the enhancement of TNF-alpha mRNA levels was suppressed by pretreatment with U73122 (which inhibits phospholipase C). Curcumin (an inhibitor of AP-1), suppressed the increases in both mRNAs induced by low-Mg2+ medium alone, but had no suppressive effect on the levels of either mRNA after LPS-stimulation in low-Mg2+ medium. Pyrrolidine dithiocarbamate (an inhibitor of NF-kappaB) prevented the elevation of TNF-alpha mRNA levels induced by low-Mg2+ medium without LPS-stimulation, but had no suppressive effect on IL-1beta mRNA levels. From these results, we conclude that the enhanced elevation of IL-1beta and TNF-alpha mRNA levels seen in LPS-stimulated alveolar macrophages in low-Mg2+ medium occurs partly via the same, and partly via different, signaling pathways. 相似文献
94.
Yasunori Cho Satoru Suzuki Masakazu Yokoi Muneaki Shimada Saburo Kuwabara Akira Murayama 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2004,52(10):476-479
Lymphoblastic lymphoma, an aggressive mediastinal mass, is recognized as serious threat to the patient in developing cardiac
tamponade or airway obstruction. Surgical procedure is often required to relieve clinical emergency and to establish prompt
pathological diagnosis. However, in such a patient, acute respiratory occlusion in the spine position can be a life-threatening
complication during general anesthesia. We describe a 17-year-old man whose cardiac tamponade was treated by pericardial-pleural
window through a left anterior thoracotomy in the lateral position. The patient recovered from hemodynamic compromise without
showing respiratory occlusion during general anesthesia and remained in the lateral position until extubation. Pathological
diagnosis was precursor T-lymphoblastic lymphoma. There were no complications attributable to the operative procedure. Further
chemotherapy reduced the mediastinal mass in size after two weeks when the patient developed sepsis and died. Lateral position
prevents respiratory occlusion during surgical procedure under general anesthesia in the patient of huge anterior mediastinal
tumor with airway obstruction. 相似文献
95.
Shintaro Nemoto Kiyomitsu Yasuhara Katsutoshi Nakamura Yutaka Miyoshi Akira Sakai 《Annals of thoracic and cardiovascular surgery》2004,10(1):19-22
Carnitine is an essential cofactor for fatty acid (FA) metabolism, the predominant source of ATP in the normal aerobic heart. During myocardial ischemia, FA metabolism is impaired and tissue carnitine levels are depleted. Since the heart cannot synthesize carnitine, plasma carnitine could play an important role in maintaining myocardial carnitine levels during reperfusion. The purpose of this study was to determine the incidence of abnormal plasma carnitine concentrations in open heart surgery. Blood samples were obtained from eleven patients before, immediately after, and two hours after cardiopulmonary bypass (CPB). Total and free carnitine levels were significantly reduced immediately after CPB (p<0.01) and remained depressed until two hours after CPB (p<0.01 vs. pre CPB), while acyl carnitine levels were unchanged over the course of this study. These depressed free carnitine levels might affect cardiac metabolism in the heart after open heart surgery. Carnitine supplement might be a useful adjunct in the therapy after open heart surgery. 相似文献
96.
Masashi Kato Shinji Sato Misako Suzuki Hiroko Oka Yuko Kaneko Hidekata Yasuoka Takaki Nojima Akira Suwa Michito Hirakata Yasuo Ikeda 《Nihon Rinshō Men'eki Gakkai kaishi》2004,27(5):345-349
A 52 year-old woman noticed general fatigue, polyarthralgia, and muscle weakness of lower extremities in October 2001. In December, she felt difficulty in walking due to muscle weakness. In January 2002, she admitted another hospital because of dyspnea on exertion and edema of lower extremities. Laboratory test revealed leukocytopenia, the elevation of creatine kinase and positive anti-U1-RNP antibodies. Her chest computed tomography (CT) showed severe interstitial pneumonia. Cardiac echogram revealed that she had pericardial effusion and pulmonary hypertension. Then she was transferred to Keio University Hospital and she was diagnosed as having mixed connective tissue disease (MCTD) manifestating myositis, interstitial pneumonia, pulmonary hypertension and pericarditis. Prednisolone (PSL) 60mg daily following to methylprednisolone (mPSL) pulse therapy was begun and her symptoms were gradually improved. In middle of February, she complained of high fever over 39.0 degrees C. Bacterial culture tests were negative and laboratory data indicated pancytopenia and a high level of serum ferritin. Bone marrow aspiration revealed hemophagocytosis in bone marrow specimens and she was diagnosed as having hemophagocytic syndrome associated with MCTD. mPSL pulse therapy was not effective and intermittent cyclophosphamide pulse therapy (IV-CY) was performed resulting in improvement of the symptoms. This case suggested the effectiveness of IV-CY therapy in patients with corticosteroid-resistant HPS associated with connective tissue diseases. 相似文献
97.
Hisashi Masugata Shoichi Senda Fuminori Goda Yumiko Yoshihara Kay Yoshikawa Norihiro Fujita Hiroyuki Daikuhara Hiroyuki Nakamura Teruhisa Taoka Masakazu Kohno 《Hypertension research》2006,29(11):897-903
The purpose of the present study was to elucidate the cardiac structure and function in patients who have metabolic syndrome but no history of cardiovascular disease by analyzing echocardiographic findings. Echocardiographic examination was performed to screen for cardiovascular disease in 135 patients who were in their sixties. Patients were divided into metabolic syndrome (n=65, age: 65+/-2.7 years) and non-metabolic syndrome (n=70, age: 66+/-2.5 years) groups based on the criteria for metabolic syndrome proposed by the Japanese Society of Hypertension and seven other societies in 2005. The left ventricular (LV) wall thickness and dimension were measured by M-mode echocardiography. The relative wall thickness, LV mass index, and LV ejection fraction (LVEF) were calculated. LV diastolic function was assessed by the peak velocity of early rapid filling (E velocity) and the peak velocity of atrial filling (A velocity), and the ratio of E to A (E/A) was assessed by the transmitral flow. The Tei index, which reflects both LV diastolic and systolic function, was also calculated. There were no differences in relative wall thickness, LV mass index, or LVEF between the two groups. However, both the EIA and Tei index were significantly different between the metabolic syndrome (0.66+/-0.14 and 0.36+/-0.07, respectively) and non-metabolic syndrome (0.88+/-0.25 and 0.29+/-0.09) groups (p<0.001). These results indicate that patients with metabolic syndrome can have cardiac diastolic dysfunction even if they have neither LV hypertrophy nor systolic dysfunction. 相似文献
98.
Tatsuo Shirota Mie Tashiro Kohsuke Ohno Akira Yamaguchi 《Journal of oral and maxillofacial surgery》2003,61(4):471-480
PURPOSE: This study investigated the effect of parathyroid hormone (1-34) [PTH(1-34)] on bone reactions after tibial placement of titanium screw implants into ovariectomized rats. MATERIALS AND METHODS: Twelve-week-old female Wistar rats were divided into 3 groups of 24. The first group (Sham group) was sham-operated; the second group (OVX group) was ovariectomized only; and the third group (PTH group) was subcutaneously administered 30 microg/kg PTH in the dorsal region 3 days per week starting the fourth week after ovariectomy until the end of the experiment. Titanium screw implants were placed in the proximal metaphysis of the tibia of all 3 groups at 168 days after surgery. The animals were killed 7, 14, 28, and 56 days after implantation. Undecalcified sections were prepared and evaluated by light microscopy. Histomorphometric measurements were obtained using a computer-based image analyzer to quantify the unit bone mass around the implant and the rate of implant-bone contact. RESULTS: When PTH administration was started 21 days after ovariectomy, the volume density of bone around implants in the PTH group was almost the same as that of the Sham group throughout the entire observation period. This finding suggests that not only can intermittent human PTH(1-34) administration prevent resorption of newly generated trabeculae around an implant but also it can aid in the recovery of bone volume lost due to ovariectomy. CONCLUSION: When dental implants are applied to jaw bone showing trabecular bone loss, it may be possible to increase bone density around an implant by intermittent human PTH(1-34) administration and thereby improve clinical results. 相似文献
99.
Hirofumi Fukushima Emiko Katou Kouji Nagayama Akira Shirachi Michio Sata 《Nihon Shokakibyo Gakkai zasshi》2006,103(6):661-666
A 80-year old man was referred to our hospital because of an elevation of serum amylase level. Diffuse enlargement of the pancreas was detected by abdominal computed tomography, and also diffuse narrowing of the main pancreatic duct was revealed using endoscopic retrograde cholangiopancreatography. The serum level of IgG was elevated to 3450mg/dl. Besides, on the 10th hospital day, petechia developed and the platelet level decreased to 1.5 x 10(4)/microl. The platelet-associated IgG, antiplatelet antibody and antinuclear antibody in serum were positive. The levels of serum complements were low. From all these findings the patient was diagnosed as autoimmune pancreatitis complicated with immune thrombocytopenia. The treatment with prednisolone was started, which was effective on each disease. The medication was suspended a year ago, and so far there is no data suggesting the recurrence of autoimmune pancreatitis or immune thrombocytopenia. 相似文献
100.
J R Roelandt G R Sutherland K Yoshida J Yoshikawa 《Journal of the American College of Cardiology》1988,12(3):807-811
Three patients with a left ventricular pseudoaneurysm are presented. Doppler color flow imaging helped to establish the diagnosis and was able to show additional blood flow abnormalities. The guided continuous wave Doppler interrogation of the shunting blood flow through the communication between the pseudoaneurysm and the left ventricle allowed the identification of a specific diagnostic flow pattern. Doppler color flow imaging offers advantages in patients with equivocal two-dimensional echocardiographic findings for elucidating confusing clinical findings and demonstrating additional and unsuspected flow abnormalities. 相似文献