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991.
Shogo Tajima Kenji Koda 《International journal of clinical and experimental pathology》2015,8(5):5113-5120
Development of malignant peripheral nerve sheath tumors (MPNSTs) is a stepwise process that involves the alteration of many cell cycle regulators and the double inactivation of the NF1 gene. Inactivation of the TP53 gene and deletion of the CDKN2A/p16 gene are known to play an important role in the process. Herein, we present a 19-year-old man with a familial history of neurofibromatosis type 1, in whom the tumor arose from the intercostal nerve and showed 3 components: a neurofibroma, a low-grade MPNST, and a high-grade MPNST. Loss of p16 expression and homozygous deletion of the CDKN2A/p16 gene were observed in both the low-grade and the high-grade MPNST. In contrast to low-grade MPNSTs, high-grade MPNSTs generally tend to lose expression of p16 and harbor homozygous deletion of the CDKN2A/p16 gene. Loss of p16 expression and homozygous deletion of the CDKN2A/p16 gene in low-grade MPNST in our case might be related to its progression to high-grade MPNST. To the best of our knowledge, this is the first study correlating the p16 expression status and CDKN2A/p16 gene alteration in low-grade MPNSTs. 相似文献
992.
Shogo Tajima Akihiko Ohata Kenji Koda Yasuhiko Maruyama 《International journal of clinical and experimental pathology》2015,8(5):5821-5829
Activating mutations of platelet-derived growth factor receptor α (PDGFRA) are detected in a significant proportion of gastrointestinal stromal tumors (GISTs), in addition to the more frequent mutation in c-kit. GISTs with PDGFRA mutations have been found to have several characteristic morphological features, sometimes allowing to discriminate them from GISTs with c-kit mutations. Among these, epithelioid morphology in tumor cells and tumor-infiltrating mast cells are powerful predictors of PDGFRA mutations. Although myxoid stroma by itself is not so much a reliable predictor of PDGFRA mutation, myxoid stroma in conjunction with epithelioid morphology in tumor cells is a powerful predictor of mutations in this gene. GISTs showing either weak or negative immunoreactivity for c-kit and epithelioid cells with myxoid stroma are called myxoid epithelioid GISTs, which typically show PDGFRA mutation. Herein, we presented a case of a 59-year-old woman with myxoid epithelioid GIST of the stomach. A unique finding in this case was eosinophil infiltration, probably more numerous than mast cells; mast cell infiltration is known to be usually found in myxoid epithelioid GIST. The existence of a similar mechanism in eosinophil and mast cell recruitment via tumor-producing stem cell factor is speculated. Mutational analyses revealed a PDGFRA exon 18 mutation: D842_H845del, D846N. Combined deletion and substitution mutation has been reported in rare instances, but to the best of our knowledge, D846N has not been documented. 相似文献
993.
Shigeo Suzuki Kenji Hikosaka Emmanuel O. Balogun Keisuke Komatsuya Mamoru Niikura Fumie Kobayashi Kiwamu Takahashi Tohru Tanaka Motowo Nakajima Kiyoshi Kita 《Antimicrobial agents and chemotherapy》2015,59(11):6960-6967
5-Aminolevulinic acid (ALA) is a naturally occurring amino acid present in diverse organisms and a precursor of heme biosynthesis. ALA is commercially available as a component of cosmetics, dietary supplements, and pharmaceuticals for cancer diagnosis and therapy. Recent reports demonstrated that the combination of ALA and ferrous ion (Fe2+) inhibits the in vitro growth of the human malaria parasite Plasmodium falciparum. To further explore the potential application of ALA and ferrous ion as a combined antimalarial drug for treatment of human malaria, we conducted an in vivo efficacy evaluation. Female C57BL/6J mice were infected with the lethal strain of rodent malaria parasite Plasmodium yoelii 17XL and orally administered ALA plus sodium ferrous citrate (ALA/SFC) as a once-daily treatment. Parasitemia was monitored in the infected mice, and elimination of the parasites was confirmed using diagnostic PCR. Treatment of P. yoelii 17XL-infected mice with ALA/SFC provided curative efficacy in 60% of the mice treated with ALA/SFC at 600/300 mg/kg of body weight; no mice survived when treated with vehicle alone. Interestingly, the cured mice were protected from homologous rechallenge, even when reinfection was attempted more than 230 days after the initial recovery, indicating long-lasting resistance to reinfection with the same parasite. Moreover, parasite-specific antibodies against reported vaccine candidate antigens were found and persisted in the sera of the cured mice. These findings provide clear evidence that ALA/SFC is effective in an experimental animal model of malaria and may facilitate the development of a new class of antimalarial drug. 相似文献
994.
Sonographic evaluation of the medial aspect of the knee in a population‐based cohort study 下载免费PDF全文
995.
Yu Sawada Tetsuya Honda Sho Hanakawa Satoshi Nakamizo Teruasa Murata Yuri Ueharaguchi-Tanada Sachiko Ono Wataru Amano Saeko Nakajima Gyohei Egawa Hideaki Tanizaki Atsushi Otsuka Akihiko Kitoh Teruki Dainichi Narihito Ogawa Yuichi Kobayashi Takehiko Yokomizo Makoto Arita Motonobu Nakamura Yoshiki Miyachi Kenji Kabashima 《The Journal of experimental medicine》2015,212(11):1921-1930
Resolvin E1 (RvE1) is a lipid mediator derived from ω3 polyunsaturated fatty acids that exerts potent antiinflammatory roles in several murine models. The antiinflammatory mechanism of RvE1 in acquired immune responses has been attributed to attenuation of cytokine production by dendritic cells (DCs). In this study, we newly investigated the effect of RvE1 on DC motility using two-photon microscopy in a contact hypersensitivity (CHS) model and found that RvE1 impaired DC motility in the skin. In addition, RvE1 attenuated T cell priming in the draining lymph nodes and effector T cell activation in the skin, which led to the reduced skin inflammation in CHS. In contrast, leukotriene B4 (LTB4) induced actin filament reorganization in DCs and increased DC motility by activating Cdc42 and Rac1 via BLT1, which was abrogated by RvE1. Collectively, our results suggest that RvE1 attenuates cutaneous acquired immune responses by inhibiting cutaneous DC motility, possibly through LTB4-BLT1 signaling blockade.Following the well-known epidemiological study conducted in Northwest Greenland in the 1970s (Dyerberg et al., 1978), several clinical assessments have indicated that a diet rich in ω3 polyunsaturated fatty acids (PUFAs) has beneficial effects in various inflammatory diseases, including asthma, psoriasis, inflammatory bowel diseases, and rheumatoid arthritis (Horrobin, 1987). Although it remains unclear how ω3 PUFAs exert such antiinflammatory effects, recent studies have identified several derivatives of ω3 PUFAs that possess strong antiinflammatory effects (Serhan et al., 2008; Tull et al., 2009). Resolvin E1 (RvE1) is one such antiinflammatory lipid mediator.RvE1 is known to exert its actions through two receptors, BLT1 and ChemR23 (Arita et al., 2007). RvE1 binds to BLT1, a G protein–coupled receptor for leukotriene B4 (LTB4), and inhibits BLT1 signals (Arita et al., 2007). In addition, RvE1 exhibits an agonistic activity toward ChemR23 (Arita et al., 2007), a G protein–coupled receptor for chemerin. The antiinflammatory effects of RvE1 have been demonstrated in acute innate immune inflammation, such as peritonitis (Arita et al., 2007) and colitis (Arita et al., 2005b). In these models, RvE1 exerted its antiinflammatory effects by inhibiting neutrophil infiltration into the inflammatory foci through a blockade of LTB4-BLT1 signaling in neutrophils (Haas-Stapleton et al., 2007). In contrast, few studies have been conducted on the effect of RvE1 on acquired immune responses, in which DCs and T cells play major roles in the development. In these studies, the attenuated cytokine production, such as IL-12 and IL-23, from DCs is considered as the major mechanism by which RvE1 exerts the antiinflammatory effects (Arita et al., 2005a; Haworth et al., 2008). However, the effect of RvE1 on DC motility has not been investigated in the context of acquired immunity.In the peripheral tissues such as the skin, DCs migrate in an amoeboid movement that requires actin polymerization via activation of the Rho family of small GTPases, such as Cdc42, Rac, and Rho A (Lämmermann and Germain, 2014). In acquired immunity such as contact hypersensitivity (CHS), upon uptake of foreign antigens, DCs migrate to the draining LNs (dLNs) via lymphatic vessels to establish sensitization by inducing the antigen-specific T cell differentiation (Honda et al., 2013). In elicitation, DC migration to form DC–T cell clustering is required for efficient antigen presentation in situ (Natsuaki et al., 2014). Thus, active DC motility is an essential factor for acquired immunity.In this study, we investigated the effects and underlying mechanisms of RvE1 on DC motility using a CHS model, which is a prototype of delayed-type hypersensitivity in the skin mediated by IFN-γ (Mori et al., 2008; Honda et al., 2013). RvE1 inhibited cutaneous DC migration into the dLNs and suppressed antigen-specific T cell induction in the sensitization phase. In addition, live imaging analysis revealed that RvE1 inhibited cutaneous DC motility and cluster formation in the skin, which subsequently attenuated activation of effector T cells in the skin in the elicitation phase of CHS. Intriguingly, LTB4 induced actin filament reorganization in DCs and increased DC motility by activating Cdc42 and Rac1 via BLT1, which was abrogated by RvE1. These results suggest that RvE1 exerts its antiinflammatory effects in cutaneous acquired immunity by inhibiting DC motility, possibly through an LTB4-BLT1 signaling blockade. 相似文献
996.
Makoto Endoh Satoshi Shiono Yoshikane Yamauchi Mingyon Mun Norihiko Ikeda Hiroshi Hashimoto Hirotoshi Horio Hisao Asamura Ichiro Yoshino Haruhisa Matsuguma Jun Nakajima Takahiko Oyama Yasushi Shintani Mitsuo Nakayama Noriyuki Matsutani Masafumi Kawamura 《Journal of thoracic disease》2020,12(11):6552
BackgroundPulmonary metastasectomy (PM) for breast cancer-derived pulmonary metastasis is controversial. This study aimed to assess the prognostic factors and implication of PM for metastatic breast cancer using a multi-institutional database.MethodsClinical data of 253 females with pulmonary metastasis of breast cancer who underwent PM between 1982 and 2017 were analyzed retrospectively.ResultsThe median patient age was 56 years. The median follow-up period was 5.4 years, and the median disease-free interval (DFI) was 4.8 years. The 5- and 10-year survival rates after PM were 64.9% and 50.4%, respectively, and the median overall survival was 10.1 years. Univariate analysis revealed that the period of PM before 2000, a DFI <36 months, lobectomy/pneumonectomy, large tumor size, and lymph node metastasis were predictive of a worse overall survival. In the multivariate analysis, a DFI <36 months, large tumor size, and lymph node metastasis remained significantly related to overall survival. The 5- and 10-year cancer-specific survival rates after PM were 66.9% and 54.7%, respectively, and the median cancer-specific survival was 13.1 years. Univariate analyses revealed that the period of PM before 2000, DFI <36 months, lobectomy/pneumonectomy, large tumor size, lymph node metastasis, and incomplete resection were predictive of a worse cancer-specific survival. Multivariate analysis confirmed that a DFI <36 months, large tumor size and incomplete resection were significantly related to cancer-specific survival.ConclusionsAs PM has limited efficacy in breast cancer, it should be considered an optional treatment for pulmonary metastasis of breast cancer. 相似文献
997.
Yoshinobu Kariya Midori Oyama Mikio Ohtsuka Nobuyuki Kikuchi Yasuhiro Hashimoto Toshiyuki Yamamoto 《Fukushima journal of medical science》2020,66(3):119
α6β4 integrin plays pivotal roles in cancer progression in several types of cancers. Our previous study using N-glycan-manipulated cell lines demonstrated that defects in N-glycans or decreased β1,6GlcNAc-branched N-glycans on β4 integrin suppress β4 integrin-mediated cancer cell adhesion, migration, invasion, and tumorigenesis. Furthermore, immunohistochemical analysis has shown that colocalization of β1,6GlcNAc-branched N-glycans with β4 integrin was observed in cutaneous squamous cell carcinoma (SCC) tissue. However, until now there has been no direct evidence that β1,6GlcNAc-branched N-glycans are upregulated on β4 integrin in cutaneous SCC. In the present study, we performed an ELISA analysis of β1,6GlcNAc-branched N-glycans on β4 integrins as well as β4 integrins in cell lysates from human normal skin and cutaneous SCC tissues. The SCC samples showed a 4.9- to 7.4-fold increase in the ratio of β1,6GlcNAc-branched N-glycans to β4 integrin compared with normal skin samples. These findings suggest that the addition of β1,6GlcNAc-branched N-glycans onto β4 integrin was markedly elevated in cutaneous SCC tissue compared to normal skin tissue. The value of β1,6GlcNAc-branched N-glycans on β4 integrin may be useful as a diagnostic marker associated with cutaneous SCC tumor progression. 相似文献
998.
999.
1000.
Soo Ryang Kim Fukuo Kondo Yumi Otono Susumu Imoto Kenji Ando Makoto Hirakawa Katsumi Fukuda Madoka Sasaki Soo Ki Kim Takamitsu Komaki Shinobu Tsuchida Sawako Kobayashi Toshiyuki Matsuoka Masatoshi Kudo 《Hepatology research》2014,44(5):584-590
We describe a case of serum amyloid A (SAA) and C‐reactive protein (CRP) positive nodule detected by immunohistochemical analysis in a 37‐year‐old woman with alcohol‐related cirrhosis. Imaging studies at first admission pointed to hepatocellular carcinoma (HCC), a dysplastic nodule, an inflammatory pseudotumor or focal nodular hyperplasia (FNH). Ultrasonography‐guided biopsy in Segment 2 showed minimal atypical changes, except for a slight increase in cell density and micronodular cirrhosis in the non‐nodular portion. gadolinium‐ethoxybenzyl‐diethylenetriamine pentaacetic acid‐enhanced magnetic resonance imaging carried out after a year and a half revealed hypervascularity in the arterial phase and isointensity in the hepatobiliary phase. Three years thereafter, however, the imaging displayed a change from isointensity to a defect in the hepatobiliary phase, and the nodule demonstrated minimal histological atypia. Immunohistochemical staining of the nodule was positive for SAA, CRP, liver fatty acid‐binding protein and glutamine synthetase, but negative for β‐catenin, heat shock protein 70 and Glypican 3. Organic anion transporter (OATP)8 staining was weaker in the nodule than in the non‐nodular portion of the alcohol‐related micronodular cirrhosis. The nodule was diagnosed as an SAA and CRP positive nodule, and HCC was ruled out. Despite the change from isointensity to a defect in the hepatobiliary phase, no evidence of HCC was found in the biopsy specimen. The change may be explained more by the weak OATP8 staining compared with that of alcohol‐related liver cirrhosis than by malignant transformation into HCC. 相似文献