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11.
We report the effects of intravenous infusion of CGS-19755, a potent competitive N-methyl-D-aspartate (NMDA) antagonist, on local cerebral pH (LCpH) and local CBF (LCBF) in rats with occluded left middle cerebral and common carotid arteries. LCpH and LCBF were determined simultaneously by a double-label autoradiographic technique 4 h after vascular occlusion in three groups: no treatment, carrier infused, and a group receiving CGS-19755 at 10 mg/kg bolus immediately after occlusion followed by infusion at 5 mg kg-1 h-1 for 4 h. Compared with rats receiving carrier, several cortical structures on the side of occlusions showed significantly higher CBF in rats receiving CGS-19755. This drug also corrected the pH in several left cortical structures to values significantly higher than in the rats receiving carrier. The correction in LCpH was not limited to those regions showing significant elevations in LCBF. In the nonoccluded hemisphere, CGS-19755 significantly increased the hemispheric mean blood flow from 122 +/- 17 to 221 +/- 64 ml 100 g-1 min-1 (mean +/- SD of all structures, p less than 0.01) without any changes in LCpH. Cortical but not basal ganglia infarct volume was significantly smaller in rats receiving CGS-19755 than in the carrier-treated group. These results suggest that, at least partially, the neuroprotective effect of CGS-19755 in ischemia may be related to changes in CBF and pH in addition to its antagonist effect on the NMDA receptor. 相似文献
12.
T Koike T Hirono T Takizawa Y Yamato T Souma K Yoshiya K Nakayama M Tsuchida S Eguchi 《[Zasshi] [Journal]. Nihon Kyōbu Geka Gakkai》1990,38(7):1172-1175
By the end of 1988, seventy five cases after pulmonary resection for lung cancer and one case after pulmonary resection for basal cell hyperplasia were examined with fiberoptic bronchoscopy as postoperative follow up. Endobronchial tumor was detected in 14 cases. In seven cases, endobronchial tumor was located at site far from the surgical bronchial anastomosis. These tumors were suspected as second lung cancer as long as examined by fiberoptic bronchoscopy. Histological type of all of these was squamous cell carcinoma. Re-operations were performed in five cases and two of them were early lung cancer. In 6 cases (13.6%) among 44 cases examined with fiberoptic bronchoscopy after pulmonary resection for central type squamous cell carcinoma, second lung cancer was detected. In the case of central type squamous cell carcinoma, usually the tumor appears to be of same histological type and at same location. Among those cases those who smoke heavily should be separated as high risk group. If this group is followed with fiberoptic bronchoscopy or sputum cytological examination, it is more possible to detect second lung cancer at an early stage. 相似文献
13.
Cyclosporin-A (CsA) has greatly influenced the outcome of organ transplantation and has also been effective in the treatment of many autoimmune diseases. Unfortunately, it has deleterious effects on bone remodelling, causing a high turnover bone loss, with bone resorption exceeding bone formation. Salmon calcitonin (SCtn) has been shown to inhibit bone resorption in high turnover states such as Paget's disease and postmenopausal osteoporosis. In an attempt to attenuate the high turnover bone remodelling caused by CsA alone, we studied the bone mineral effects of CsA in combination with SCtn in male Sprague-Dawley rats. Group A (n = 20) received vehicle as control, group B (n = 20) received CsA (15 mg/kg BW) by daily gavage and SCtn vehicle sc, group C (n = 20) received SCtn (1.3 IU/kg BW) daily sc and CsA vehicle, and group D (n = 20) received a combination of CsA and Ctn daily, as described above. Rats were bled weekly for determination of circulating biochemical bone parameters. Eight rats from each group were killed on day 14 (short term), and the remaining rats were killed on day 28 (long term). Tibiae were removed for bone histomorphometry after death, which revealed a reduction of trabecular bone volume and an increase in osteoclast number induced by CsA alone. These changes were significantly attenuated by the combination of CsA and SCtn to resemble the histomorphometry of the control group. The inhibition of osteoclast number by SCtn is the most plausible mechanism by which the combination therapy attenuates the high turnover bone loss induced by CsA alone. 相似文献
14.
Postoperative bronchial stump fistula responding well to occlusion with metallic coils and fibrin glue via a tracheostomy: a case report. 总被引:3,自引:0,他引:3
Junzo Shimizu Masaya Takizawa Tsuyoshi Yachi Yoshihiko Arano Yasumitsu Hirano Ryuichi Waseda Shiro Takahashi Yoshio Tsunezuka 《Annals of thoracic and cardiovascular surgery》2005,11(2):104-108
An 80-year-old man underwent middle and lower lobectomy of the right lung to treat squamous cell carcinoma (SCC) (4 cm in diameter) originating from the right B4 bronchus. On the 4th postoperative day, a massive air leak from the thoracic drain was noted. At that time, a diagnosis of bronchial stump fistula was made on the basis of the bronchoscopic findings. Continuous thoracic drainage, aspiration of sputum via a tracheostomy and intravenous administration of antibiotics were performed immediately after the diagnosis. However, the patient's condition was complicated by aspiration pneumonia. On the 11th postoperative day, bronchoscopic procedure to close the bronchial fistula was performed via the tracheostomy. During this procedure, metallic coils were first inserted into the fistula to serve as the core for occlusion. Then, instead of directly infusing fibrin glue, several small beans-sized pieces of Surgicell cotton (Johnson & Johnson Co., Cincinnati, OH) soaked in fluid A (concentrated fibrinogen) and the same number of Surgicell cotton pieces soaked in fluid B (thrombin) were alternately inserted into the fistula, to allow closure of the bronchial fistula. After this procedure, the embolus created remained in place without being expectorated, and the aspiration pneumonia entered remission, allowing the patient to be discharged from the hospital on the 24th postoperative day. At preset, 14 months after surgery, the patient is in good condition. This technique allows simple and reliable closure of a fistula if a tracheostomy is available. It should be selected as a therapy of first choice when dealing with patients with a postoperative bronchial stump fistula in poor general condition. Patients undergoing right pneumonectomy or middle and lower lobectomy of the right lung should be considered as belonging to a high risk group for bronchial fistula and as requiring preventable measures (e.g., covering the stump with an intercostal muscle flap). 相似文献
15.
Abe S Takizawa H Sugawara I Kudoh S 《American journal of respiratory cell and molecular biology》2000,22(3):296-303
We devised a new in vitro cell exposure system to freshly generated diesel exhaust (DE), different from conventional in vitro culture systems, to examine the effects of DE on human epithelial cells. Using this system, we investigated the effects of DE on cytokine gene expressions in BET-1A human bronchial epithelial cells. DE significantly decreased [(3)H]thymidine incorporation into BET-1A cells. DE had a significant stimulatory effect on interleukin (IL)-8 release to a marked degree. IL-8 and transforming growth factor (TGF)-beta1 messenger RNA (mRNA) expression were induced by DE in a time-dependent manner. The gas obtained by filtration of DE alone did not show a sustained increase in IL-8 protein levels and showed no induction of IL-8 mRNA, suggesting that DE particles (DEPs) play an important role in the induction of IL-8 at both mRNA and protein levels. Antioxidants, pyrrolidine dithiocarbamate, and N-acetyl-L-cysteine significantly inhibited IL-8 mRNA and protein levels by BET-1A cells. These results indicate that freshly generated DEPs may be important in the induction of cytokines such as IL-8 and TGF-beta1 relevant to allergic airway inflammation. 相似文献
16.
Yanagisawa M Nakashima K Ochiai W Takizawa T Setoguchi T Uemura A Takizawa M Nobuhisa I Taga T 《Neuroscience research》2005,53(2):176-182
Mammalian cells that have been committed to a certain cell lineage cannot be directed to other lineages. However, some astrocytes in the mammalian brains have been reported to represent plasticity to redirect to other cell lineages. We found that mouse hippocampal astrocytes cultured in aggregate forms of "astrosphere", redirected to MAP2-positive immature neurons. In astrospheres, basic HLH factors positively regulating neuronal differentiation were up-regulated and Id3 inhibiting basic HLH factors was down-regulated. Ectopic Id3 induction repressed redirection of astrocytes to a neuronal lineage, suggesting that astrosphere formation induced plasticity of astrocytes by changing the gene expression patterns. 相似文献
17.
Quantitative Analysis of Mycobacterial and Propionibacterial DNA in Lymph Nodes of Japanese and European Patients with Sarcoidosis 总被引:10,自引:0,他引:10 下载免费PDF全文
Yoshinobu Eishi Moritaka Suga Ikuo Ishige Daisuke Kobayashi Tetsuo Yamada Tamiko Takemura Touichiro Takizawa Morio Koike Shoji Kudoh Ulrich Costabel Josune Guzman Gianfranco Rizzato Marcello Gambacorta Ronald du Bois Andrew G. Nicholson Om P. Sharma Masayuki Ando 《Journal of clinical microbiology》2002,40(1):198-204
The cause(s) of sarcoidosis is unknown. Mycobacterium spp. are suspected in Europe and Propionibacterium spp. are suspected in Japan. The present international collaboration evaluated the possible etiological links between sarcoidosis and the suspected bacterial species. Formalin-fixed and paraffin-embedded sections of biopsy samples of lymph nodes, one from each of 108 patients with sarcoidosis and 65 patients with tuberculosis, together with 86 control samples, were collected from two institutes in Japan and three institutes in Italy, Germany, and England. Genomes of Propionibacterium acnes, Propionibacterium granulosum, Mycobacterium tuberculosis, Mycobacterium avium subsp. paratuberculosis, and Escherichia coli (as the control) were counted by quantitative real-time PCR. Either P. acnes or P. granulosum was found in all but two of the sarcoid samples. M. avium subsp. paratuberculosis was found in no sarcoid sample. M. tuberculosis was found in 0 to 9% of the sarcoid samples but in 65 to 100% of the tuberculosis samples. In sarcoid lymph nodes, the total numbers of genomes of P. acnes or P. granulosum were far more than those of M. tuberculosis. P. acnes or P. granulosum was found in 0 to 60% of the tuberculosis and control samples, but the total numbers of genomes of P. acnes or P. granulosum in such samples were less than those in sarcoid samples. Propionibacterium spp. are more likely than Mycobacteria spp. to be involved in the etiology of sarcoidosis, not only in Japanese but also in European patients with sarcoidosis. 相似文献
18.
N-methyl-D-aspartate receptor antagonist reduces nitrotyrosine formation in caudate-putamen in rat focal cerebral ischemia-reperfusion 总被引:2,自引:0,他引:2
Hirabayashi H Takizawa S Fukuyama N Nakazawa H Shinohara Y 《Neuroscience letters》2001,299(1-2):159-161
The aim of this study is to determine experimentally whether N-methyl-D-aspartate (NMDA) receptor is involved in nitrotyrosine formation in rat brain subjected to focal ischemia-reperfusion, by using the NMDA receptor antagonist MK-801. Halothane-anesthetized and artificially ventilated rats were given MK-801 (5 mg/kg, i.p.) or vehicle prior to 2 h of focal cerebral ischemia followed by 0.5 h of reperfusion. The brain was then removed and divided into four sections, cortical ischemic core, peri-ischemic cortex, lateral caudate-putamen and non-ischemic cortex. Tissue nitrotyrosine was measured by means of hydrolysis/HPLC. MK-801 significantly attenuated nitrotyrosine formation in the lateral caudate-putamen. We conclude that nitrotyrosine formation required activation of NMDA receptors, at least in part. 相似文献
19.
Polyketones with carbonyl groups in the polymer backbone (ethylene-carbon monoxide copolymer) have been converted into a novel polyoxime by means of C-nitrosation of the methylene groups and oximation of the carbonyl groups. The polyoxime is considered to be composed largely of 1,2-bis(hydroxyimino)trimethylene units. From the polyoxime and divalent Fe-, Co-, or Ni-salts, polymeric metal chelate complexes were prepared which are capable of combining reversibly with molecular oxygen and, especially the Fe-complex, also with carbon monoxide. 相似文献
20.