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71.
The steady-state level of Mg-protoporphyrin IX is not a determinant of plastid-to-nucleus signaling in Arabidopsis 总被引:2,自引:1,他引:2
Mochizuki N Tanaka R Tanaka A Masuda T Nagatani A 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(39):15184-15189
The plastid plays a vital role in various cellular activities within plant cells including photosynthesis and other metabolic pathways. It is believed that the functional status of the plastid is somehow monitored by the nucleus to optimize the expression of genes encoding plastid proteins. The currently dominant model for plastid-derived signaling (“plastid signaling”) proposes that Mg-protoporphyrin IX (MgProto) is a negative signal that represses the expression of a wide range of nuclear genes encoding plastid-localized proteins when plastid development is inhibited. In this study, we have re-evaluated this hypothesis by quantifying the steady-state levels of MgProto (as well as its neighboring intermediates protoporphyrin IX and Mg-Proto monomethyl ester [MgProtoMe]) in Arabidopsis plants with altered plastid signaling responses as monitored by expression of the Lhcb1, RBCS, HEMA1, BAM3 and CA1 genes. In addition, we have examined the correlation between gene expression and MgProto (MgProtoMe) in a range of mutants and conditions in which the steady-state levels of MgProto (MgProtoMe) have been modified. Overall we found that there was no correlation between the steady-state levels of MgProto (MgProtoMe) and Lhcb1 expression or with any of the other genes tested. Taking these results together, we propose that the current model on plastid signaling must be revised. 相似文献
72.
Matsuo K Nagano Y Sugimori K Taniguchi K Gorai K Kunisaki C Ike H Tanaka K Imada T Kamijo S Nozawa A Nakatani Y Miura Y Tanaka K Endo I Sekido H Togo S Shimada H 《Journal of gastroenterology》2005,40(3):306-311
Primary malignant peripheral nerve-sheath tumors of the common bile duct are extremely rare. To our knowledge, the published literature contains no previous case report of this disease. Here we report on a 58-year-old Japanese woman with a primary malignant peripheral nerve-sheath tumor of the common bile duct, which was completely resected. A hypoechoic mass was identified in the hepatic hilus, using ultrasonography and computed tomography. Endoscopic retrograde cholangiography revealed a smooth stricture and deviation of the common bile duct. Laparotomy exposed a firm mass around the common bile duct that had not invaded the surrounding tissues. Partial resection of the common bile duct and cholecystectomy were performed as the treatment of choice. The final histopathological diagnosis was malignant peripheral nerve-sheath tumor arising from the wall of the common bile duct. 相似文献
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75.
Keiji Suzuki Noriyuki Sakata Katsuya Hiraishi Ichiro Mori Masamitsu Takatama 《ACTA HISTOCHEMICA ET CYTOCHEMICA》2014,47(5):211-217
Hypertensive rat arteries exhibited severe medial smooth muscle cell injury and necrosis. Electron microscopic observations showed the smooth muscle cells of these arteries exhibited characteristics of focal cytoplasmic necrosis forming new cytodemarcating membrane between the healthy cytoplasm and necrotic cytoplasm. When the focal necrotic cytoplasm disappeared from the injured smooth muscle cells, it left it with a moth-eaten leaf-like appearance (moth-eaten necrosis). At an advanced stage of injury, smooth muscle cells changed to islet-like cell bodies with newly formed basement membranes around them, and further islet-like cell bodies and cell debris disappeared leaving lamellar and reticular basement membranes.In hypertensive rats injected with nitroblue tetrazolium (NBT), formazan deposits were observed in the medial cells and nitrotyrosine, a biomarker of peroxynitrite, were immunohistochemically observed in the arterial media. Nick-end positive extranuclear small granular bodies, which might have derived from focal necrotic cytoplasm and nucleus, were detected in the arterial media using DNA nick-end labeling method. Based on electron microscopical and histochemical findings, we conjectured that the focal cytoplasmic necrosis of the smooth muscle cells in the arterial media depended on injury arising from mitochondria-derived oxidants. 相似文献
76.
Mariko Oishi Katsuya Yamazaki Fuminobu Okuguchi Hidekatsu Sugimoto Azuma Kanatsuka Atsunori Kashiwagi Japan Diabetes Clinical Data Management Study Group 《Journal of diabetes investigation.》2014,5(5):581-587
Aims/Introduction
Six kinds of oral antidiabetic drugs (OADs), including the new dipeptidyl peptidase 4 (DPP‐4) inhibitors, are available. The present study aimed to define trends within the prescribing patterns of OADs, as well as changes in glycemic control in Japan over a 10‐year period from 2002 to 2011.Materials and Methods
We carried out a cross‐sectional study using data of type 2 diabetes mellitus patients from 24 clinics for 2002, 2005, 2008 and 2011. OAD use was analyzed combined with clinical data.Results
Sulfonylureas (SUs) were the most commonly used OAD, but their use for monotherapy markedly decreased over the study period. Biguanides (BGs) were the second most commonly used OAD, and their prescribing rate increased both for mono‐ and combination therapy. DPP‐4 inhibitors (DPP‐4I), released in 2009, were the third most commonly prescribed OAD in 2011 both for mono‐ and combination therapy. Among combination therapies, two OADs were mostly prescribed, but the use of three OADs and four OADs in 2011 was two‐ and 14.8‐fold those in 2002. These trends were accompanied by an improvement in average glycated hemoglobin from 7.5 ± 1.2% in 2002 to 7.1 ± 0.9% in 2011.Conclusions
The OAD prescribing trend has moved away from monotherapy with SUs and toward combination therapies to achieve better glycemic control. Increased use of BGs and DPP‐4I was predominant in 2011. These trends were accompanied by an improvement of the glycated hemoglobin level. 相似文献77.
Pillai SK Abdel-Mohsen M Guatelli J Skasko M Monto A Fujimoto K Yukl S Greene WC Kovari H Rauch A Fellay J Battegay M Hirschel B Witteck A Bernasconi E Ledergerber B Günthard HF Wong JK;Swiss HIV Cohort Study 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(8):3035-3040
78.
Lee SY Miyai K Han HS Hwang DY Seong MK Chung H Jung BH Devaraj B McGuire KL Carethers JM 《Digestive diseases and sciences》2012,57(1):72-78
Background and Objectives
Colorectal tumors are often observed with tumor infiltrating lymphocytes, presumably as a host-immune response, and patterns may segregate by types of genomic instability. Microsatellite unstable (MSI) colorectal cancers contain a pronounced lymphocyte reaction that can pathologically identify these tumors. Colorectal tumors with elevated microsatellite alterations at selected tetranucleotide repeats (EMAST) have not been examined for lymphocyte patterns. 相似文献79.
Ayasa Matsuda Keiko Hara Miho Miyajima Eisuke Matsushima Katsuya Ohta Masato Matsuura 《Clinical neurophysiology》2013,124(6):1115-1121
Objective: The aim of the present study was to examine patterns of neural activity in response to variations in scale notes and alterations from a scale note to a non-scale note.Methods: Event-related potentials (ERPs) were recorded in response to scale and non-scale violin notes using an odd-ball mismatch negativity (MMN) paradigm. Standard stimuli were set to the scale note A4 (440 Hz). Deviant stimuli included two scale notes (scale-B, B4 = 494 Hz; scale-C, C5 = 523 Hz) and a non-scale note halfway between them (non-scale, B4 + 42¢ = 506 Hz).Results: MMN amplitude elicited by the non-scale was significantly larger than that elicited by the scale-B and scale-C, which did not differ significantly from one another.Conclusion: The current results suggest that the human brain may possess pre-attentive mechanisms for extracting relational aspects among sounds of the musical scale.Significance: The results indicate that non-scale notes may be processed in a different way even in the pre-attentive stage than scale notes. 相似文献
80.
Maki Nishimura Junko Kohara Jun Hiasa Yoshikage Muroi Naoaki Yokoyama Katsuya Kida Xuenan Xuan Hidefumi Furuoka Yoshifumi Nishikawa 《Clinical and Vaccine Immunology : CVI》2013,20(2):309-312
Histopathology and quantitative PCR (qPCR) were used to determine the tissue distribution of Neospora caninum in calves at 80 days postinfection. Our findings revealed that the most appropriate brain areas for researching N. caninum pathogenesis were the amygdala and hippocampus for qPCR and the corpus striatum and diencephalon for histopathology. 相似文献