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71.
To evaluate coronary hemodynamics and myocardial perfusion, left coronary digital subtraction angiography (DSA) and Tl-201 myocardial scintigraphy were performed in patients with syndrome X. The coronary circulation time (CCT) was significantly prolonged after the injection of isosorbide dinitrate and contrast medium i.c. Apical T1/2 was also prolonged on ergonovine malate provocation test. We suspected that the vascular response of the coronary peripheral artery was impaired, and microvascular spasm probably existed in patients with syndrome X. The prevalence of abnormal myocardial perfusion defect on exercise Tl-201 SPECT in syndrome X was very high, and coronary hemodynamics was significantly disturbed in the group of syndrome X with abnormal Tl-201 SPECT. Tl-201 lung/heart count ratio significantly increased in syndrome X on treadmill test. Because of this, exercise induced left ventricular dysfunction was suspected. We concluded that the main pathophysiological finding of impaired coronary circulation in syndrome X was microvascular spasm. 相似文献
72.
Tumors from 40 patients and 7 established human xenograft tumor lines were grown in three-dimensional histoculture. A Viable-Cell-Index (VCI) based on fluorescent dyes and Growth Fraction Index (GFI) based on [3H]thymidine incorporation were measured by confocal microscopy and histological autoradiography, respectively, after treatment with cytotoxic agents. Chemosensitivity in vitro with the two methods was correlated with chemosensitivity of the same set of human xenografted tumor lines grown in nude mice. The percent accuracy of in vitro to in vivo correlation with VCI (73%) was higher than GFI (63%). The number of false positives with VCI was 12.1% (4/33), and with GFI was 31.3% (10/32). The results thus indicated that in vitro histoculture with fluorescent vital-dye end-points to measure cell viability is of potential use to determine tumor chemosensitivity. 相似文献
73.
We compared the effect of seton (White pump shunt) surgery (16 eyes) with that of trabeculectomy and 5-fluorouracil (31 eyes) in treating 38 Asian patients with medically uncontrollable neovascular glaucoma. We found the probability of long-term success (intraocular pressure < or = 26 > or = 5 mm Hg) of seton surgery (53.0% at 3 years) to be similar to that obtained following trabeculectomy with adjunctive 5-fluorouracil (45.4% at 3 years). However, 3 years postoperatively, the probability of the preservation of visual acuity was significantly greater following trabeculectomy than seton surgery (67.1% vs 23.1%; P < .05). In addition, the prevalence of postoperative complications was higher with the seton procedure (P < .001). The loss of endothelial cells 6 months postoperatively was more marked with seton surgery than with trabeculectomy, whether the shunt device touched the cornea (P < .000001) or not (P < .0005). In conclusion, White's pump shunt was effective in lowering the IOP of eyes with neovascular glaucoma. However, care must be taken to prevent postoperative complications, the incidence of which exceeded those observed following trabeculectomy with adjunctive 5-fluorouracil. 相似文献
74.
Norihiro Ishida Koji Hayashi Asuka Hattori Keiichiro Yogo Toru Kimura Tatsuo Takeya 《Journal of bone and mineral research》2006,21(1):48-57
We found that a chemokine receptor gene, CCR1, acts downstream of NFAT2 in RANKL-stimulated RAW264 and bone marrow cells. The upstream regulatory region of CCR1 showed RANKL-dependent and CsA-suppressible promoter activity. Downregulation of the expression and function of CCR1 suppressed cell migration. INTRODUCTION: We previously reported that the expression of NFAT2 induced by RANKL is a key process for progression to multinucleated cells in an in vitro osteoclastogenesis system. Identifying the target genes of NFAT2 would thus be informative about the differentiation process. We focused here on chemokine and chemokine receptor genes that act downstream of NFAT2 in RAW264 cells as well as osteoclast precursors prepared from bone marrow cells. MATERIALS AND METHODS: RAW264 mouse monocyte/macrophage line cells were cultured with or without cyclosporin A (CsA) in the presence of RANKL or glutathione S-transferase (GST). Osteoclast precursors were prepared from bone marrow cells. RANKL-inducible and CsA-suppressible genes were searched for by microarray analysis, and expression was confirmed by quantitative RT-PCR. Promoter activity was measured by luciferase gene reporter assay. Short interfering (si)RNA for CCR1 was introduced in RAW264 cells. Cell migration activity was examined using a Boyden chamber assay. RESULTS AND CONCLUSIONS: We identified the chemokine receptor gene CCR1 as a gene showing significant differential expression profiles in osteoclastogenesis in the presence versus the absence of CsA, an inhibitor of NFAT. This property was unique to CCR1 among the chemokine and chemokine receptor genes examined in both RAW264 and bone marrow cells. The upstream regulatory region was isolated from CCR1, and its RANKL-dependent and CsA-suppressible promoter activity was confirmed. The functional significance of CCR1 was assessed by monitoring the migration of cells in a transwell migration assay, and this activity was abolished when either CsA- or CCR1 siRNA-treated cells were used. Moreover, treatment with a Galpha inhibitor pertussis toxin (PTX) or methiolynated-regulated on activation, normal T cells expressed and secreted (Met-RANTES), an antagonist of CCR1, suppressed multinucleated cell formation in the bone marrow cell system. Together, these results suggest that the CCR1 signaling cascade is under the control of NFAT2 and seems to enhance the migration of differentiating osteoclasts. 相似文献
75.
Hirofumi CHIBA Surapon PIBOONPOCANUN Hiroaki MITSUZAWA Koji KURONUMA Robert C. MURPHY Dennis R. VOELKER 《Respirology (Carlton, Vic.)》2006,11(Z1):S2-S6
Objectives: The pulmonary surfactant system of the human lung consists of unique lipids and proteins that contribute to the biophysical and innate immune properties of the organ. Surfactant protein A (SP‐A) is an oligomeric protein consisting of 18 protomers with collagen and lectin–like domains that recognizes glycoconjugates, lipids and protein determinants on both host cells and invading microorganisms. The authors examined the interaction of SP‐A with Mycoplasma pneumoniae and the influence of the protein upon the innate immune response to the bacteria. Methodology: The authors quantified SP‐A interaction with bacteria using ELISA, and identified the major surface ligand by thin layer chromatography, HPLC and mass spectrometry. The inflammatory response of human and rat macrophages was measured by quantifying tumour necrosis factor‐α secretion using ELISA, and nitric oxide production. Results: SP‐A bound the bacteria with high affinity and enhanced the inflammatory response of human and rat macrophages to the organism and its membranes. Analysis of the interaction of SP‐A with the bacteria revealed that the major ligand was a phospholipid. The lipid ligand was purified by a combination of thin layer and HPLC, and identified by mass spectrometry. The mass spectrometry demonstrated that the SP‐A reactive lipid consisted of several disaturated molecular species of phosphatidylglycerol (PtdGro). Additional experiments were performed to determine if disaturated PtdGro was capable of interfering with the action of SP‐A as an inhibitor of bacterial lipopolysaccharide‐induced inflammatory mediator production by macrophages. The disaturated PtdGro failed to alter the anti‐inflammatory action of SP‐A but unexpectedly these same studies revealed that unsaturated PtdGro can modify the host response to lipopolysaccharide. Conclusions: These findings reveal that both the lipids and proteins of pulmonary surfactant play a role in regulating the host response to invading microorganisms. 相似文献
76.
Osamu Kikuchi Hiroyuki Murai Koji Ikezoe Masakazu Kawajiri Yasumasa Ohyagi Emiko Isogai Jun-ichi Kira 《Clinical neurology》2004,44(4-5):299-302
A 58-year-old woman suffered from stiffness, swelling, rubor and muscle pain in the extremities one month after she climbed a mountain in Kyushu, an island in southern Japan. On admission, mild proximal weakness was present in the extremities. Her range of motion in the extremities was limited due to firm skin and subcutaneous stiffness which was similar to scleroderma. She showed peripheral blood eosinophilia and hypergammaglobulinemia as well as a high erythrocyte sedimentation rate. An IgM antibody against Borrelia afzelii was positive. MRI of the skeletal muscles demonstrated enhancing fascia around the biceps brachii muscle, and a biopsy specimen revealed perivascular infiltration of mononuclear cells within the hypertrophic fascia. Eosinophilic infiltration was absent. We treated the patient with prednisolone, doxycycline and amoxicillin, which alleviated the symptoms. This is the first report to show that Borrelia afzelii was involved in eosinophilic fasciitis. 相似文献
77.
The present study was undertaken to elucidate the effect on platelet aggregation of the prothrombin-converting reaction on platelets with or without activated protein C (APC). A reaction mixture of washed platelets from human individuals, Factor Xa and prothrombin markedly induced platelet aggregation; maximum aggregation rates, 31.3–92.5%, and times to reach to maximum aggregation, 11.6 to 20.1 min. This aggregation was inhibited by the addition of APC with 50% inhibition concentration (IC50) value of 14.4 U/ml. APC also inhibited thrombin generation in the reaction mixture in a dose-dependent manner with IC50 value of 0.96 U/ml. However, APC did not inhibit the thrombin (0.1 CU/ml)-induced platelet aggregation at concentrations of up to 30 U/ml. These findings suggest that APC has no direct inhibitory effect on platelet aggregation and that APC inhibits platelet aggregation through inhibition of thrombin generation. 相似文献
78.
Bunta Kato Koji Yamada Masahiro Horiuchi Toshikazu Hirayama Yasuhiro Hasegawa 《Clinical neurology》2007,47(9):577-580
A 79-year-old woman with a 4-year history of Parkinson's disease was admitted due to unique dyspneic attacks with cyanosis while eating. Dyspneic attacks with cyanosis occurred mainly during actions such as taking meals or rehabilitation. Due to increased tonus of the orbicularis oris muscle, she was unable to open her mouth and breathe out, and finally experienced hypoxemia as revealed by pulse oxymetry. Dystonic hypertonus was relieved by touching the mandible with the fingers, and she was able to open her mouth again. These symptom was compatible with the sensory trick. Based on these findings, we considered that dyspneic attacks were produced by focal oromandibular dystonia. Polysomnography also showed central sleep apnea. We report herein a rare case of Parkinson's disease presenting with respiratory insufficiency caused by focal dystonia and central sleep apnea. 相似文献
79.
80.
Pharmacologic preconditioning effects: Prostaglandin E1 induces heat-shock proteins immediately after ischemia/reperfusion of the mouse liver 总被引:1,自引:0,他引:1
Ken-ichi Matsuo M.D. Shinji Togo M.D. Ph.D. Hitoshi Sekido M.D. Ph.D. Tomoyuki Morita M.D. Ph.D. Masako Kamiyama Ph.D. Daisuke Morioka M.D. Ph.D. Toru Kubota M.D. Ph.D. Yasuhiko Miura M.D. Ph.D. Kuniya Tanaka M.D. Ph.D. Takashi Ishikawa M.D. Ph.D. Yasushi Ichikawa M.D. Ph.D. Itaru Endo M.D. Ph.D. Hitoshi Goto M.D. Ph.D. Hiroyuki Nitanda M.D. Ph.D. Yasushi Okazaki M.D. Ph.D. Yoshihide Hayashizaki M.D. Ph.D. Hiroshi Shimada M.D. Ph.D. 《Journal of gastrointestinal surgery》2005,9(6):758-768
Prostaglandin E1 (PGE1) has several potential therapeutic effects, including cytoprotection, vasodilation, and inhibition of platelet aggregation. This study investigates the protective action of PGE1 against hepatic ischemia/reperfusion injury in vivo using a complementary DNA microarray. PGE1 or saline was continuously administered intravenously to mice in which the left lobe of the liver was made ischemic for 30 minutes and then reperfused. Livers were harvested 0, 10, and 30 minutes postreperfusion. Messenger RNA was extracted, and the samples were labeled with two different fluorescent dyes and hybridized to the RIKEN set of 18,816 full-length enriched mouse complementary DNA microarrays. Serum alanine aminotransferase and aspartate aminotransferase levels at 180 minutes postreperfusion were significantly lower in the PGE1-treated group than in the saline-treated group. The cDNA microarray analysis revealed that the genes encoding heat-shock protein (HSP) 70, glucose-regulated protein 78, HSP86, and glutathione S-transferase were upregulated at the end of the ischemic period (0 minutes postreperfusion) in the PGE1 group. Our results suggested that PGE1 induces HSPs immediately after ischemia reperfusion. HSPs might therefore play an important role in the protective effects of PGE1 against ischemia/reperfusion injury of the liver. 相似文献