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141.
Saito A Ueda K Imamura M Miura N Atsumi S Tabunoki H Sato R 《Developmental and comparative immunology》2004,28(1):1-7
An antibacterial peptide from the hemolymph of a coleopteran insect, Acalolepta luxuriosa, in the superfamily Cerambyocidea was characterized. The mature antibacterial peptide had 27 amino acid residues with a theoretical molecular weight of 3099.29 and it showed antibacterial activity against Escherichia coli and Micrococcus luteus. The deduced amino acid sequence of the peptide showed that it had a cysteine-stabilized alphabeta motif with a C...CXXXC...C...CXC consensus sequence, like insect defensins. However, the results of a multiple sequence alignment and phylogenetic analysis with CLUSTAL X indicated that this peptide is a novel peptide with a cysteine-stabilized alphabeta motif that is distant from insect defensins. 相似文献
142.
It is difficult to match annual vaccines against the exact influenza strain that is spreading in any given flu season. Owing to the emergence of drug-resistant viral strains, new approaches for treating influenza are needed. Euglena gracilis (hereinafter Euglena), microalga, used as functional foods and supplements, have been shown to alleviate symptoms of influenza virus infection in mice. However, the mechanism underlying the inhibitory action of microalgae against the influenza virus is unknown. Here, we aimed to study the antiviral activity of Euglena extract against the influenza virus and the underlying action mechanism using Madin–Darby canine kidney (MDCK) cells. Euglena extract strongly inhibited infection by all influenza virus strains examined, including those resistant to the anti-influenza drugs oseltamivir and amantadine. A time-of-addition assay revealed that Euglena extract did not affect the cycle of virus replication, and cell pretreatment or prolonged treatment of infected cells reduced the virus titer. Thus, Euglena extract may activate the host cell defense mechanisms, rather than directly acting on the influenza virus. Moreover, various minerals, mainly zinc, in Euglena extract were found to be involved in the antiviral activity of the extract. In conclusion, Euglena extract could be a potent agent for preventing and treating influenza. 相似文献
143.
Shin Yajima Ayaka Satoh Naosumi Sekiya Sachiko Yamazaki Hisashi Uemura Hiroe Tanaka Mitsuhiro Yamamura Taichi Sakaguchi 《Clinical Case Reports》2021,9(12)
In patients with a narrow sinotubular junction, small sinus of Valsalva, or extensibility loss in the aortic root, aortic valve replacement (AVR) with a standard valve is challenging due to limited surgical field. Detailed preoperative measurements of the aortic root render performing AVR using the Perceval valve easy. 相似文献
144.
Ayaka J. Iwata Anna S. Wertz Spandana Alluri Michael C. Singer 《American journal of otolaryngology》2019,40(6):102292
ObjectiveTo assess the capacity of different techniques to reduce non-operative times during parathyroid surgery. The impact of monitored anesthesia care (MAC) instead of general anesthesia, and the pre-operative placement of a second peripheral intravenous catheter (PIV) were analyzed.MethodsA retrospective case series at an academic medical center was performed to study patients undergoing parathyroidectomy by a single surgeon between November 2013 and October 2016. Three operating room (OR) time measurements were compared: pre-incision time, post-closure time, and total OR time.ResultsSurgeries performed under MAC (n = 21) had statistically shorter pre-incision (33.2 min vs. 39.7 min, p < .001), post-closure (10.1 min vs. 16.2 min, p = .002), and total operative times (113.0 min vs. 151.5 min, p < .001) compared to those in which general anesthesia (n = 169) was used. Of the 169 patients who underwent general anesthesia, 25 had a second PIV placed preoperatively and 144 had only a single PIV. All 3 time periods were statistically shorter in patients who had a second PIV versus those who had only a single PIV (pre-incision 32.2 min vs. 41.0 min, p < .001; post-closure 12.2 min vs. 16.9 min, p < .001; total 117.9 min vs. 157.4 min, p < .001).ConclusionsIn patients undergoing parathyroid surgery in which ioPTH levels will be used, the placement of a second PIV in the pre-operative holding area and performance of surgery under MAC can significantly shorten non-operative and total OR time. 相似文献
145.
Nobuyuki Kabasawa Eisuke Shiozawa So Murai Mayumi Homma Yuka Uesugi Tomoharu Matsui Ayaka Nakata Shotaro Shimada Yohei Sasaki Yuta Baba Megumi Watanuki Nana Arai Shun Fujiwara Yukiko Kawaguchi Hiroyuki Tsukamoto Yui Uto Kouji Yanagisawa Norimichi Hattori Hirotaka Sakai Hiroshi Harada Tsuyoshi Nakamaki Masafumi Takimoto Toshiko Yamochi-Onizuka 《Journal of Clinical and Experimental Hematopathology》2021,61(3):120
Post-transplant lymphoproliferative disorder (PTLD) and other iatrogenic immunodeficiency-associated lymphoproliferative disorders (OIIA-LPD) are iatrogenic lymphoproliferative disorders (LPD) that develop in association with immunosuppressive treatment in the setting of organ transplantation and autoimmune disease, respectively. Each has a spectrum of pathologies ranging from lymphoid hyperplasia to lymphoma. To clarify the characteristics of the diffuse large B-cell lymphoma (DLBCL) subtype in a cohort of 25 patients with PTLD or OIIA-LPD from our institute, we selected 13 with a histological subtype of DLBCL, including 2 cases of PTLD and 11 of OIIA-LPD. The median patient age at diagnosis was 70 years, with a female predominance. Both PTLD cases developed after kidney transplant. Of the patients with OIIA-LPD, 10 had rheumatoid arthritis, 1 had mixed connective tissue disease, and 8 were treated using methotrexate. Both of the PTLD patients and 6 of the OIIA-LPD patients had extranodal manifestations. All patients except for one were classified as having the non-germinal center B-cell (non-GCB) subtype according to the Hans algorithm. Tissue samples from 8 patients were positive for CD30 and 8 were positive for Epstein–Barr virus (EBV)-encoded small RNA. Seven patients had MYC-positive tissue samples, but none had MYC translocation. Our study suggests that extranodal manifestations and the non-GCB subtype are common, that EBV is associated with the DLBCL subtype of PTLD and OIIA-LPD, and that anti-CD30 therapy is applicable. In addition, our patients with the DLBCL subtype of PTLD and OIIA-LPD exhibited MYC overexpression without MYC translocation, suggesting an alternative mechanism of MYC upregulation. 相似文献
146.
147.
Takahiro Aoki Mariko Takami Tomozumi Takatani Kiwamu Motoyoshi Ayana Ishii Ayaka Hara Takahide Toyoda Reona Okada Moeko Hino Ryo Koyama‐Nasu Masahiro Kiuchi Kiyoshi Hirahara Motoko Y. Kimura Toshinori Nakayama Naoki Shimojo Shinichiro Motohashi 《Cancer science》2020,111(7):2223-2233
Invariant natural killer T (iNKT) cells are innate‐like CD1d‐restricted T cells that express the invariant T cell receptor (TCR) composed of Vα24 and Vβ11 in humans. iNKT cells specifically recognize glycolipid antigens such as α‐galactosylceramide (αGalCer) presented by CD1d. iNKT cells show direct cytotoxicity toward CD1d‐positive tumor cells, especially when CD1d presents glycolipid antigens. However, iNKT cell recognition of CD1d‐negative tumor cells is unknown, and direct cytotoxicity of iNKT cells toward CD1d‐negative tumor cells remains controversial. Here, we demonstrate that activated iNKT cells recognize leukemia cells in a CD1d‐independent manner, however still in a TCR‐mediated way. iNKT cells degranulated and released Th1 cytokines toward CD1d‐negative leukemia cells (K562, HL‐60, REH) as well as αGalCer‐loaded CD1d‐positive Jurkat cells. The CD1d‐independent cytotoxicity was enhanced by natural killer cell‐activating receptors such as NKG2D, 2B4, DNAM‐1, LFA‐1 and CD2, but iNKT cells did not depend on these receptors for the recognition of CD1d‐negative leukemia cells. In contrast, TCR was essential for CD1d‐independent recognition and cytotoxicity. iNKT cells degranulated toward patient‐derived leukemia cells independently of CD1d expression. iNKT cells targeted myeloid malignancies more than acute lymphoblastic leukemia. These findings reveal a novel anti–tumor mechanism of iNKT cells in targeting CD1d‐negative tumor cells and indicate the potential of iNKT cells for clinical application to treat leukemia independently of CD1d. 相似文献
148.
149.
Generation of neural crest-derived peripheral neurons and floor plate cells from mouse and primate embryonic stem cells 总被引:18,自引:0,他引:18 下载免费PDF全文
Mizuseki K Sakamoto T Watanabe K Muguruma K Ikeya M Nishiyama A Arakawa A Suemori H Nakatsuji N Kawasaki H Murakami F Sasai Y 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(10):5828-5833
To understand the range of competence of embryonic stem (ES) cell-derived neural precursors, we have examined in vitro differentiation of mouse and primate ES cells into the dorsal- (neural crest) and ventralmost (floor plate) cells of the neural axis. Stromal cell-derived inducing activity (SDIA; accumulated on PA6 stromal cells) induces cocultured ES cells to differentiate into rostral CNS tissues containing both ventral and dorsal cells. Although early exposure of SDIA-treated ES cells to bone morphogenetic protein (BMP)4 suppresses neural differentiation and promotes epidermogenesis, late BMP4 exposure after the fourth day of coculture causes differentiation of neural crest cells and dorsalmost CNS cells, with autonomic system and sensory lineages induced preferentially by high and low BMP4 concentrations, respectively. In contrast, Sonic hedgehog (Shh) suppresses differentiation of neural crest lineages and promotes that of ventral CNS tissues such as motor neurons. Notably, high concentrations of Shh efficiently promote differentiation of HNF3beta(+) floor plate cells with axonal guidance activities. Thus, SDIA-treated ES cells generate naive precursors that have the competence of differentiating into the "full" dorsal-ventral range of neuroectodermal derivatives in response to patterning signals. 相似文献
150.