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91.
Makino A Iinuma M Fukumitsu H Soumiya H Furukawa Y Furukawa S 《Biomedical research (Tokyo, Japan)》2010,31(6):379-386
We presently found that medium-chain fatty acids (MCFAs) with 8-12 carbons and their esters facilitated activation (phosphorylation) of mitogen-activated protein kinases (MAPK)/extracellular signal-regulated kinases (ERK) 1/2 of cultured embryonic cortical/hippocampal neurons. In particular, trans-2-decenoic acid ethyl ester (DAEE) had the most potent activity. Additionally, DAEE activated phosphatidylinositol 3-kinase and cAMP-response element binding protein (CREB), suggesting that DAEE generates similar intracellular signal as neurotrophins. Therefore, details of the signal elicited by DAEE were examined in comparison with those of a neurotrophin, brain-derived neurotrophic factor (BDNF). We found that 1) DAEE phosphorylated MAPK/ERK1/2 via MEK activation without the involvement of tyrosine kinases of neurotrophin Trk receptors; 2) DAEE activated CREB predominantly through MAPK/ERK1/2 activation, not through other pathways such as cAMP/protein kinase A; and 3) DAEE increased the expression of RNAs of BDNF and neurotrophin-3 and the protein content of synapse-specific proteins such as synaptophysin, synapsin-1, and syntaxin. Based on these observations we propose that DAEE and some other derivatives of MCFAs having neurotrophin-like neurotrophic activities may become therapeutic tools for certain neurological or psychiatric disorders. 相似文献
92.
Miyoshi H Sato K Niino D Arakawa F Kimura Y Kiyasu J Takeuchi M Yoshida M Okada Y Nakamura Y Sugita Y Ohshima K 《American journal of clinical pathology》2012,137(6):879-889
We examined clinicopathologic findings in 17 cases of peripheral T-cell lymphoma, follicular variant (f-PTCL), and compared these findings with angioimmunoblastic T-cell lymphoma (AITL) to determine whether they were identical to the spectrum of changes seen in AITL and how each of the findings in f-PTCL were related to the characteristics of AITL. Almost all f-PTCL cases showed pathologic characteristics of AITL and immunohistochemical positivities in lymphoma cells for CD4, CD10, Bcl-6, PD-1, and CXCL13. Except for pathologic characteristics, clinicopathologic findings in f-PTCL had few significant differences from AITL. The positive rate for Bcl-6 expression in neoplastic cells was significantly associated with the frequency of polymorphic infiltrates, vascular proliferation, B-immunoblasts, clear cells, Epstein-Barr virus-positive lymphocytes, hepatosplenomegaly, and skin rash. Our study confirmed the continuity between f-PTCL and AITL. Moreover, Bcl-6 expression in f-PTCL was statistically associated with the characteristics of AITL. 相似文献
93.
94.
Nomura Y Sugita Y Yoshida S Karube K Shimizu K Aoki R Hirose S Kikuchi M Ohshima K 《Pathology international》2008,58(2):98-103
The aim of the present study was to estimate the relationship between apoptosis and cell proliferation in histiocytic necrotizing lymphadenitis (HNL). Fifteen patients with HNL were retrospectively analyzed. The patients were divided into three groups according to the proportion of the necrotic area as follows: necrosis (+), necrotic area <25%; necrosis (++), necrotic area 25–50%; and necrosis (+++), necrotic area >50%. Immunohistochemical double staining was performed for CD3 plus caspase-3 and for Ki-67 plus caspase-3 and positive cells were counted in two areas: one without and one with obvious apoptotic features. Most caspase-3-positive cells were also stained for CD3 (area exhibiting obvious apoptotic features: average, 92.3%). Furthermore, various proportions of both Ki-67- and caspase-3-positive cells were detected in all the groups (range, 5–70%). In the area with obvious apoptotic changes, the average percentage of both Ki-67- and caspase-3-positive cells (38.6%) was higher than that in the area without obvious apoptotic features (16.3%). A proportion of cells in HNL undergo proliferation and apoptosis simultaneously, such as neoplastic cells, thereby exhibiting rapid cell cycles. 相似文献
95.
Y Furukawa-Hibi A Nitta H Fukumitsu H Somiya K Toriumi S Furukawa T Nabeshima K Yamada 《Neuroscience letters》2012,522(2):79-84
Rapidly adapting mechanically activated channels (RA) are expressed on somatosensory neurons and thought to play a role in mechanical transduction. Because mechanical sensations can be significantly affected by temperatures, we examined thermal sensitivity of RA currents in cultured dorsal root ganglion (DRG) neurons to see if RA channel activity is highly temperature-dependent. RA currents were evoked from DRG neurons by membrane displacements and recorded by the whole-cell patch-clamp recording technique. We found that RA currents were significantly enhanced by warming temperatures from 22 to 32 °C and reduced by cooling temperatures from 24 to 14 °C. RA channel activation exhibited steep temperature-dependence with a large temperature coefficient (Q10>5) and a high activation energy (Ea>30 kcal/mol). We further showed that RA channel activation by mechanical stimulation led to membrane depolarization, which could result in action potential firing at 22 °C or 32 °C but not at 14 °C. Taken together, our results provide the measurements of thermal dynamics and activation energy of RA channels, and suggest that a high energy barrier is present for RA channels to open. These findings are in agreement with temperature sensitivity of mechanical sensations in mammals. 相似文献
96.
N Sugita K Yamamoto T Kobayashi W Van Der Pol T Horigome H Yoshie J G Van De Winkel K Hara 《Clinical and experimental immunology》1999,117(2):350-354
The immunoglobulin receptor Fc gamma RIIIa (CD16) is distributed on natural killer (NK) cells, macrophages, and gamma delta T cells, and is polymorphic. Fc gamma RIIIa-158V has a higher affinity for both monomeric and immune complexed IgG1, IgG3, and IgG4 than IIIa-158F. We determined Fc gamma RIIIa-158V/F genotypes of Japanese patients with adult periodontitis. A significant over-representation of Fc gamma RIIIa-158F was found in patients with recurrence, compared with patients without recurrence, making Fc gamma RIIIA a candidate gene for recurrence risk of adult periodontitis. 相似文献
97.
Niino D Ohsaki K Arakawa F Watanabe J Kimura Y Kiyasu J Takeuchi M Miyoshi H Yoshida M Sugita Y Ohshima K Okamura T 《Pathology international》2011,61(6):363-368
This report concerns a unique case of a composite lymphoma composed of T-lymphoblastic leukemia/lymphoma (T-LBL) and diffuse large B-cell lymphoma (DLBCL) in a 72-year-old woman with generalized lymphadenopathy, splenomegaly and ascites. Laboratory findings showed increased lactate dehydrogenase and soluble interleukin-2 receptor. The biopsy specimen showed replacement of the normal architecture of the lymph nodes by a tumor containing a dual cell population composed of large lymphocytes and medium-sized lymphocytes. Sheets of large lymphocytes often were punctuated by clusters of medium-sized lymphocytes. Flow cytometry and immunohistochemical analysis showed a composite lymphoma with both T-LBL and DLBCL. The T-LBL expressed CD1a, CD3, CD4, CD8, and terminal deoxynucleotidyl transferase. The DLBCL expressed CD19 and CD20, CD23, bcl-2, bcl-6, MUM1 and immunoglobulin κ light chain. Polymerase chain reaction detected a monoclonal pattern of T-cell receptor γ and immunoglobulin heavy chain rearrangements in the same specimen. She received eight cycles of R-CHOP (rituximab+cyclophosphamide, doxorubicin, vincristine, prednisone) therapy and achieved complete remission. She has shown no signs of recurrence 20 months after the diagnosis. We describe here a very unusual and, to the best of our knowledge, an as yet never reported case of a primary composite lymphoma of T-LBL and DLBCL. 相似文献
98.
99.
Isolation of Trichosporon asahii from environmental materials. 总被引:5,自引:0,他引:5
Trichosporon asahii is the most clinically important pathogenic yeast in the genus Trichosporon, as this species causes both deep-seated infection and summer-type hypersensitivity pneumonitis. We isolated 29 T. asahii colonies from environmental samples using the polymerase chain reaction (PCR) and dichloran rose bengal chloramphenicol (DRBC) medium. Our results suggest that T. asahii is common in nature. 相似文献
100.
Yuko Nomura Masanori Takeuchi Shiro Yoshida Yasuo Sugita Daisuke Niino Yoshizo Kimura Kei Shimizu Ryosuke Aoki Nobuko Suefuji Shinichi Hirose Masahiro Kikuchi Koichi Ohshima 《Pathology international》2009,59(9):631-635
Macrophage polarization is divided into M1 and M2 type based on membrane receptors, cytokines, and chemokines. M1 expresses CD80, interleukin (IL)-6, IL-12, and chemokine receptor (CCR)7, while M2 expresses CD163, IL10, and chemokine ligand (CCL)22. The aim of the present study was to identify the properties of infiltrating tissue macrophages in histiocytic necrotizing lymphadenitis (HNL). Twenty patients with HNL were studied, and immunohistochemistry for CD68 (KP1), CD163, CCL22, CCR7, and CD123 was done, along with myeloperoxidase (MPO). To evaluate the phenotypes of tissue macrophages in HNL, the number of cells stained positively for CD163, CCL22, CCR7, CD123 and MPO concurrently with CD68 was counted, and the ratio was calculated for each antibody to CD68+ cells. There was a high rate of co-expression for CD163 (median, 78%) or CCL22 (80%) and a low rate for CCR7 (5%) in CD68+ cells. It is therefore conceivable that infiltration by M2 macrophages is dominant in HNL. Furthermore, some CD68+ tissue macrophages in HNL co-express MPO or CD123 (range, 5–80%; median, 23% and 40%, respectively). It is suggested that these characteristic tissue macrophages may be associated with the pathogenesis of HNL and that M2 macrophages may infiltrate to repair the lymphoid tissue injured by cytotoxic T cells in HNL. 相似文献