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991.
992.
Transaortic stent grafting is an alternative method for treating distal arch aneurysms. Total arch grafts are too bulky to be inserted into a sheath catheter during usual stent grafting methods. An assembling method that uses a chain stitch enables the deployment of any type of stent graft into the distal aorta without the need for a sheath catheter. We describe how to safely assemble and use a branched arch stent graft. We consider this method to be beneficial in selected cases involving extensive distal arch aneurysms or in patients with highly calcified aortas. 相似文献
993.
Hiroaki Kondo Hiroeki Sahara Akihiro Miyazaki Yuki Nabeta Yoshihiko Hirohashi Takayuki Kanaseki Akira Yamaguchi Naoyuki Yamada Kazuo Hirayama Manabu Suzuki Junji Hamuro Toshihiko Torigoe Nobuaki Takahashi Gen-iku Kohama Hideyuki Ikeda Noriyuki Sato 《Cancer science》2002,93(8):917-924
A large number of human tumor antigens recognized by CD8+ cytotoxic T lymphocytes (CTL) have been identified. Some of them have been employed in clinical trials and have achieved some objective responses. However, little is known about those that are recognized by CD4+ T cells, except for a very few that were identified from melanomas. Previously, we reported that an oral squamous cell carcinoma (SCC) cell line, OSC–20, was effectively lysed by HLA-DRB1·08032 (HLA-DRS)-restricted autologous CD4+ T cell line, TcOSC–20. In this study, we performed two steps of chromatographic purification of the tumor cell lysate in combination with mass spectrometry. We found one reverse-phase high-performance liquid chromatography (RP-HPLC) fraction that was effectively recognized by the T cells. We analyzed the fraction by nano-liquid chromatography/electrospray ionization ion trap mass spectrometry (LC/MS/MS) and found six representative ions. We could determine the primary amino acid sequence of each of the six ions. Three of them contained a potential HLA-DR8 binding motif, and TcOSC–20 showed a rather strong cytotoxic response to one of the synthetic pep tides, namely, amino acid residues 321–336 of human a-enolase. Thus, several gene products of squamous cancer cells are endogenously processed and may be presented on HLA class II molecules, so that they could constitute target molecules for autologous CD4+ T cells. 相似文献
994.
Death by a dopaminergic neurotoxin, 1-methyl-4-phenylpyridinium ion (MPP) and protection by EGF in GH3 cells 总被引:1,自引:0,他引:1
In this study we investigated the uptake and effect of a dopaminergic neurotoxin, 1-methyl-4-phenylpyridinium ion (MPP+) on a clonal strain, GH3 cells, established from rat anterior pituitary. Although the level was very low compared with that in PC12 cells, a clonal rat pheochromocytoma cell line, there was a detectable amount of tyrosine hydroxylase protein in GH3 cells. The levels of monoamines including dopamine in GH3 cells were also very low compared with those in PC12 cells.
was incorporated to GH3 cells in a concentration-dependent manner and the uptake was inhibited by nomifensine, an inhibitor of dopamine transporter. Addition of 200 μM MPP+ stimulated the leakage of lactate dehydrogenase (LDH) after a lag of 24 h. Pretreatment with 50 ng/ml of epidermal growth factor (EGF), but not nerve growth factor (NGF) or brain-derived neurotrophic factor (BDNF), protected against MPP+-induced cell death. These findings show that: (1) MPP+ uptake to GH3 cells was via an effective dopamine transport system and causes delayed cell death, and (2) EGF protects against MPP+-induced cell death. A possible role for GH3 cells as dopaminergic neurons is discussed. 相似文献
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995.
Kikawada M Watanabe D Kimura A Hanyu H Serizawa H Iwamoto T 《Internal medicine (Tokyo, Japan)》2005,44(12):1312-1315
Primary Sj?gren's syndrome is an autoimmune disease characterized by lymphocytic infiltration of the salivary glands and lacrimal glands. The histological features of chronic inflammation in primary Sj?gren's syndrome may be associated with B cell hyper-reactivity. This syndrome also has various manifestations associated with other exocrine glands and nonglandular tissues. The hematological abnormalities usually seen in Sj?gren's syndrome are lymphopenia, leucopenia, and thrombocytopenia. Although the direct Coomb's test is often positive, the occurrence of autoimmune hemolytic anemia (AIHA) is rare. Here, we report an elderly patient with primary Sj?gren's syndrome who developed AIHA during the clinical course. 相似文献
996.
Morihisa Hirota Tadahiro Takada Nobuya Kitamura Tetsuhide Ito Koichi Hirata Masahiro Yoshida Toshihiko Mayumi Keisho Kataoka Kazunori Takeda Miho Sekimoto Masahiko Hirota Yasutoshi Kimura Keita Wada Hodaka Amano Toshifumi Gabata Shinju Arata Masamichi Yokoe Seiki Kiriyama 《Journal of hepato-biliary-pancreatic sciences》2010,17(1):45-52
Patients who have been diagnosed as having acute pancreatitis should be, on principle, hospitalized. Crucial fundamental management is required soon after a diagnosis of acute pancreatitis has been made and includes monitoring of the conscious state, the respiratory and cardiovascular system, the urinary output, adequate fluid replacement and pain control. Along with such management, etiologic diagnosis and severity assessment should be conducted. Patients with a diagnosis of severe acute pancreatitis should be transferred to a medical facility where intensive respiratory and cardiovascular management as well as interventional treatment, blood purification therapy and nutritional support are available. The disease condition in acute pancreatitis changes every moment and even symptoms that are mild at the time of diagnosis may become severe later. Therefore, severity assessment should be conducted repeatedly at least within 48 h following diagnosis. An adequate dose of fluid replacement is essential to stabilize cardiovascular dynamics and the dose should be adjusted while assessing circulatory dynamics constantly. A large dose of fluid replacement is usually required in patients with severe acute pancreatitis. Prophylactic antibiotic administration is recommended to prevent infectious complications in patients with severe acute pancreatitis. Although the efficacy of intravenous administration of protease inhibitors is still a matter of controversy, there is a consensus in Japan that a large dose of a synthetic protease inhibitor should be given to patients with severe acute pancreatitis in order to prevent organ failure and other complications. Enteral feeding is superior to parenteral nutrition when it comes to the nutritional support of patients with severe acute pancreatitis. The JPN Guidelines recommend, as optional continuous regional arterial infusion and blood purification therapy. 相似文献
997.
Serotonin 5‐HT1B receptor‐mediated calcium influx‐independent presynaptic inhibition of GABA release onto rat basal forebrain cholinergic neurons 下载免费PDF全文
Modulatory roles of serotonin (5‐HT) in GABAergic transmission onto basal forebrain cholinergic neurons were investigated, using whole‐cell patch‐clamp technique in the rat brain slices. GABAA receptor‐mediated inhibitory postsynaptic currents (IPSCs) were evoked by focal stimulation. Bath application of 5‐HT (0.1–300 μm ) reversibly suppressed the amplitude of evoked IPSCs in a concentration‐dependent manner. Application of a 5‐HT1B receptor agonist, CP93129, also suppressed the evoked IPSCs, whereas a 5‐HT1A receptor agonist, 8‐OH‐DPAT had little effect on the evoked IPSCs amplitude. In the presence of NAS‐181, a 5‐HT1B receptor antagonist, 5‐HT‐induced suppression of evoked IPSCs was antagonised, whereas NAN‐190, a 5‐HT1A receptor antagonist did not antagonise the 5‐HT‐induced suppression of evoked IPSCs. Bath application of 5‐HT reduced the frequency of spontaneous miniature IPSCs without changing their amplitude distribution. The effect of 5‐HT on miniature IPSCs remained unchanged when extracellular Ca2+ was replaced by Mg2+. The paired‐pulse ratio was increased by CP93129. In the presence of ω‐CgTX, the N‐type Ca2+ channel blocker, ω‐Aga‐TK, the P/Q‐type Ca2+ channel blocker, or SNX‐482, the R‐type Ca2+ channel blocker, 5‐HT could still inhibit the evoked IPSCs. 4‐AP, a K+ channel blocker, enhanced the evoked IPSCs, and CP93129 had no longer inhibitory effect in the presence of 4‐AP. CP93129 increased the number of action potentials elicited by depolarising current pulses. These results suggest that activation of presynaptic 5‐HT1B receptors on the terminals of GABAergic afferents to basal forebrain cholinergic neurons inhibits GABA release in Ca2+ influx‐independent manner by modulation of K+ channels, leading to enhancement of neuronal activities. 相似文献
998.
Nemoto T Kanai T Yanagita T Satoh S Maruta T Yoshikawa N Kobayashi H Wada A 《European journal of pharmacology》2008,586(1-3):82-89
In cultured bovine adrenal chromaffin cells, where Akt1 is the predominant isoform over Akt2 and Akt3, chronic (> or =12 h) treatment with 1-20 mM LiCl, an inhibitor of glycogen synthase kinase-3, decreased Akt1 level by approximately 52% (EC50=3.7 mM; t1/2=l2 h); it was associated with LiCl-induced increased levels of Ser9-phosphorylated glycogen synthase kinase-3beta (approximately 37%) and beta-catenin (approximately 59%), two hallmarks of glycogen synthase kinase-3beta inhibition. The same LiCl treatment did not change phosphoinositide 3-kinase, phosphoinositide-dependent kinase 1, and extracellular signal-regulated kinase-1/2 levels. Treatment with SB216763 [3-(2,4-dichlorophenyl)-4-(1-methyl-1H-indol-3-yl)-1H-pyrrole-2,5-dione], a selective inhibitor of glycogen synthase kinase-3, lowered Akt1 level by approximately 67% (EC50=2 microM; t1/2=l2 h), when SB216763 caused concentration- and time-dependent increase of beta-catenin level by approximately 76%. LiCl- or SB216763-induced Akt1 decrease, as well as increases of Ser9-phosphorylated glycogen synthase kinase-3beta and beta-catenin were restored to the control levels of nontreated cells after the washout of LiCl (20 mM for 24 h)- or SB216763 (30 microM for 24 h)-treated cells. LiCl-induced Akt1 reduction was not prevented by beta-lactone, lactacystin (two inhibitors of proteasome), calpastatin (an inhibitor of calpain), or leupeptin (an inhibitor of lysosome). LiCl decreased Akt1 mRNA level by 20% at 6 h, with no effect on Akt1 mRNA stability. These results suggest that glycogen synthase kinase-3beta inhibition caused down-regulation of Akt1 mRNA and Akt1 protein levels; conversely, constitutive activity of glycogen synthase kinase-3beta maintains steady-state level of Akt1 in quiescent adrenal chromaffin cells. 相似文献
999.
Akihiro Nakarna Seiichi Hirota Toshihiko Okazaki Kouichi Nagano Sunao Kawano Masatsugu Hori Yukihiko Kitamura 《Pathology international》1998,48(11):843-849
Interstitial cells of Cajal (ICC) are believed to lnitlate the basic contractile activity of the gastrointestlnal tract. Interstitial cells of Cajal express c-kit receptor tyroslne kinase and are deficient in Ws/Ws mutant rats with a small deletion of the c-kit gene . As Ws/Ws rats show remarkable bile reflux to the stomach, the contraction pressure of the pylorus was compared between Ws/Ws and control +/+ rats. The contraction pressure of the pylorus was measured using a mlcrotransducer, which was Inserted through a pln-hole in the anterlor wall of the stomach under anesthesla. The magnitude of bile reflux was estimated by measurlng the content of bile acids In the stomach. The c-kit messenger RNA-expressing cells were detected by in sltu hybrldlzatlon. Frequency and the maxlmum pressure of the contractlon were comparable between Ws/Ws and +/+ rats, but the duration of the contractlon was significantly shorter In Ws/Ws rats than In +/+ rats. The number of c-kit messenger RNA-expresslng ICC in the pylorus of Ws/Ws rats was 1.7% that of +/+ rats. The bile reflux observed in Ws/Ws rats was attributed to the decrease in the duration of the pyloric contraction, which appeared to result from the deficlency of c-kit messenger RNA-expressing ICC. 相似文献
1000.
Yasuo Inoue Ichio Aoki Yuki Mori Yuko Kawai Toshihiko Ebisu Yasuhiko Osaka Takashi Houri Katsuyoshi Mineura Toshihiro Higuchi Chuzo Tanaka 《NMR in biomedicine》2010,23(3):304-312
Immediate and certain determination of the treatable area is important for choosing risky treatments such as thrombolysis for brain ischemia, especially in the super‐acute phase. Although it has been suggested that the mismatch between regions displaying ‘large abnormal perfusion’ and ‘small abnormal diffusion’ indicates a treatable area on an MRI, it has also been reported that the mismatch region is an imperfect approximation of the treatable region named the ‘penumbra’. Manganese accumulation reflecting calcium influx into cells was reported previously in a middle cerebral artery occlusion (MCAO) model using activity‐induced manganese‐enhanced (AIM) MRI. However, in the super‐acute phase, there have been no reports about mismatches between areas showing changes to the apparent diffusion coefficient (ADC) and regions that are enhanced in AIM MRI. It is expected that the AIM signal can be enhanced immediately after cerebral ischemia in the necrotic core region due to calcium influx. In this study, a remote embolic rat model, created using titanium‐oxide macrospheres, was used to observe necrotic neural responses in the super‐acute phase after ischemia. In addition, images were evaluated by comparison between ADC, AIM MRI, and histology. The signal enhancement in AIM MRI was detected at 2 min after the cerebral infarction using a remote embolic method. The enhanced area on the AIM MRI was significantly smaller than that on the ADC map. The tissue degeneration highlighted by histological analysis corresponded more closely to the enhanced area on the AIM MRI than that on the ADC map. Thus, the manganese‐enhanced region in brain ischemia might indicate ‘necrotic’ irreversible tissue that underwent calcium influx. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献