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991.
Increased CD11b+ Gr‐1+ cell population in the placenta after infection with Toxoplasma gondii
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Kinuko Takeshima Kazuki Sato Tsukasa Nabekura Kisaburo Nagamune Hiromi Hamada Hiroyuki Yoshikawa Akira Shibuya Kazuko Shibuya 《Microbiology and immunology》2015,59(2):95-98
Toxoplasma gondii is an obligate intracellular protozoan pathogen that can cross the placenta, resulting in congenital toxoplasmosis with severe fetal brain abnormalities. The molecular mechanisms of immune responses against T. gondii infection in the placenta have largely remained unclear. An analytical method for characterizing phenotypes of immune cells in the placenta by flow cytometry was established and it was found that numbers of CD11b+ Gr‐1+ cells in the placenta increased significantly after T. gondii infection. These results suggest that innate immune responses play an important role in immunity against T. gondii infection via the feto‐maternal interface. 相似文献
992.
Kenta Maruyama Masahiro Fukasaka Satoshi Uematsu Osamu Takeuchi Takeshi Kondo Tatsuya Saitoh Mika?l M. Martino Shizuo Akira 《The Journal of biological chemistry》2015,290(15):9377-9386
5-Azacytidine-induced protein 2 (AZI2) is a TNF receptor (TNFR)-associated factor family member-associated NF-κB activator-binding kinase 1-binding protein that regulates the production of IFNs. A previous in vitro study showed that AZI2 is involved in dendritic cell differentiation. However, the roles of AZI2 in immunity and its pleiotropic functions are unknown in vivo. Here we report that AZI2 knock-out mice exhibit normal dendritic cell differentiation in vivo. However, we found that adult AZI2 knock-out mice have severe osteoporosis due to increased osteoclast longevity. We revealed that the higher longevity of AZI2-deficient osteoclasts is due to an augmented activation of proto-oncogene tyrosine-protein kinase Src (c-Src), which is a critical player in osteoclast survival. We found that AZI2 inhibits c-Src activity by regulating the activation of heat shock protein 90 (Hsp90), a chaperone involved in c-Src dephosphorylation. Furthermore, we demonstrated that AZI2 indirectly inhibits c-Src by interacting with the Hsp90 co-chaperone Cdc37. Strikingly, administration of a c-Src inhibitor markedly prevented bone loss in AZI2 knock-out mice. Together, these findings indicate that AZI2 regulates bone mass by fine-tuning osteoclast survival. 相似文献
993.
Yuichi Hirata Hao-Wei Li Kazuko Takahashi Hiroshi Ishii Megan Sykes Joji Fujisaki 《PloS one》2015,10(11)
NK cells resist engraftment of syngeneic and allogeneic bone marrow (BM) cells lacking major histocompatibility (MHC) class I molecules, suggesting a critical role for donor MHC class I molecules in preventing NK cell attack against donor hematopoietic stem and progenitor cells (HSPCs), and their derivatives. However, using high-resolution in vivo imaging, we demonstrated here that syngeneic MHC class I knockout (KO) donor HSPCs persist with the same survival frequencies as wild-type donor HSPCs. In contrast, syngeneic MHC class I KO differentiated hematopoietic cells and allogeneic MHC class I KO HSPCs were rejected in a manner that was significantly inhibited by NK cell depletion. In vivo time-lapse imaging demonstrated that mice receiving allogeneic MHC class I KO HSPCs showed a significant increase in NK cell motility and proliferation as well as frequencies of NK cell contact with and killing of HSPCs as compared to mice receiving wild-type HSPCs. The data indicate that donor MHC class I molecules are required to prevent NK cell-mediated rejection of syngeneic differentiated cells and allogeneic HSPCs, but not of syngeneic HSPCs. 相似文献
994.
Identifying Pelagic Habitat Hotspots of Neon Flying Squid in the Temperate Waters of the Central North Pacific 总被引:1,自引:0,他引:1
Irene D. Alabia Sei-Ichi Saitoh Robinson Mugo Hiromichi Igarashi Yoichi Ishikawa Norihisa Usui Masafumi Kamachi Toshiyuki Awaji Masaki Seito 《PloS one》2015,10(11)
We identified the pelagic habitat hotspots of the neon flying squid (Ommastrephes bartramii) in the central North Pacific from May to July and characterized the spatial patterns of squid aggregations in relation to oceanographic features such as mesoscale oceanic eddies and the Transition Zone Chlorophyll-a Front (TZCF). The data used for the habitat model construction and analyses were squid fishery information, remotely-sensed and numerical model-derived environmental data from May to July 1999–2010. Squid habitat hotspots were deduced from the monthly Maximum Entropy (MaxEnt) models and were identified as regions of persistent high suitable habitat across the 12-year period. The distribution of predicted squid habitat hotspots in central North Pacific revealed interesting spatial and temporal patterns likely linked with the presence and dynamics of oceanographic features in squid’s putative foraging grounds from late spring to summer. From May to June, the inferred patches of squid habitat hotspots developed within the Kuroshio-Oyashio transition zone (KOTZ; 37–40°N) and further expanded north towards the subarctic frontal zone (SAFZ; 40–44°N) in July. The squid habitat hotspots within the KOTZ and areas west of the dateline (160°W-180°) were likely influenced and associated with the highly dynamic and transient oceanic eddies and could possibly account for lower squid suitable habitat persistence obtained from these regions. However, predicted squid habitat hotspots located in regions east of the dateline (180°-160°W) from June to July, showed predominantly higher squid habitat persistence presumably due to their proximity to the mean position of the seasonally-shifting TZCF and consequent utilization of the highly productive waters of the SAFZ. 相似文献
995.
Atsushi Musha Hirofumi Shimada Katsuyuki Shirai Jun-ichi Saitoh Satoshi Yokoo Kazuaki Chikamatsu Tatsuya Ohno Takashi Nakano 《PloS one》2015,10(10)
Purpose
To evaluate the dose-response relationship for development of acute radiation mucositis (ARM) using an oral mucosal dose surface model (OMDS-model) in carbon ion radiotherapy (C-ion RT) for head and neck tumors.Methods
Thirty-nine patients receiving C-ion RT for head and neck cancer were evaluated for ARM (once per week for 6 weeks) according to the Common Terminology Criteria for Adverse Events (CTCAE), version 4.0, and the Radiation Therapy Oncology Group (RTOG) scoring systems. The irradiation schedule typically used was 64 Gy [relative biological effectiveness (RBE)] in 16 fractions for 4 weeks. Maximum point doses in the palate and tongue were compared with ARM in each patient.Results
The location of the ARM coincided with the high-dose area in the OMDS-model. There was a clear dose-response relationship between maximum point dose and ARM grade assessed using the RTOG criteria but not the CTCAE. The threshold doses for grade 2–3 ARM in the palate and tongue were 43.0 Gy(RBE) and 54.3 Gy(RBE), respectively.Conclusions
The OMDS-model was useful for predicting the location and severity of ARM. Maximum point doses in the model correlated well with grade 2–3 ARM. 相似文献996.
Kazuko Omodaka Takaaki Horii Seri Takahashi Tsutomu Kikawa Akiko Matsumoto Yukihiro Shiga Kazuichi Maruyama Tetsuya Yuasa Masahiro Akiba Toru Nakazawa 《PloS one》2015,10(4)
Purpose
Although the lamina cribrosa (LC) is the primary site of axonal damage in glaucoma, adequate methods to image and measure it are currently lacking. Here, we describe a noninvasive, in vivo method of evaluating the LC, based on swept-source optical coherence tomography (SS-OCT), and determine this method’s ability to quantify LC thickness.Methods
This study comprised 54 eyes, including normal (n = 18), preperimetric glaucoma (PPG; n = 18), and normal tension glaucoma (NTG; n = 18) eyes. We used SS-OCT to obtain 3 x 3 mm cube scans of an area centered on the optic disc, and then synchronized reconstructed B- and en-face images from this data. We identified the LC in these B-scan images by marking the visible borders of the LC pores. We marked points on the anterior and posterior borders of the LC in 12 B-scan images in order to create a skeleton model of the LC. Finally, we used B-spline interpolation to form a 3D model of the LC, including only reliably measured scan areas. We calculated the average LC thickness (avgLCT) in this model and used Spearman''s rank correlation coefficient to compare it with circumpapillary retinal nerve fiber layer thickness (cpRNFLT).Results
We found that the correlation coefficient of avgLCT and cpRNFLT was 0.64 (p < 0.01). The coefficient of variation for avgLCT was 5.1%. AvgLCT differed significantly in the groups (normal: 282.6 ± 20.6 μm, PPG: 261.4 ± 15.8 μm, NTG: 232.6 ± 33.3 μm). The normal, PPG and NTG groups did not significantly differ in age, sex, refractive error or intraocular pressure (IOP), although the normal and NTG groups differed significantly in cpRNFLT and Humphrey field analyzer measurements of mean deviation.Conclusion
Thus, our results indicate that the parameters of our newly developed method of measuring LC thickness with SS-OCT may provide useful and important data for glaucoma diagnosis and research. 相似文献997.
Hiroo Nakashima Kentaro Oniki Miki Nishimura Naoki Ogusu Masatsugu Shimomasuda Tatsumasa Ono Kazuki Matsuda Norio Yasui-Furukori Kazuko Nakagawa Takateru Ishitsu Junji Saruwatari 《PloS one》2015,10(10)
Valproic acid (VPA) is one of the most widely prescribed antiepileptic drugs for the treatment of epileptic seizures. Although it is well known that the doses of VPA and its plasma concentrations are highly correlated, the plasma concentrations do not correlate well with the therapeutic effects of the VPA. In this study, we developed a population-based pharmacokinetic (PK)-pharmacodynamic (PD) model to determine the optimal concentration of VPA according to the clinical characteristics of each patient. This retrospective study included 77 VPA-treated Japanese patients with epilepsy. A nonlinear mixed-effects model best represented the relationship between the trough concentrations of VPA at steady-state and an over 50% reduction in seizure frequency. The model was fitted using a logistic regression model, in which the logit function of the probability was a linear function of the predicted trough concentration of VPA. The model showed that the age, seizure locus, the sodium channel neuronal type I alpha subunit rs3812718 polymorphism and co-administration of carbamazepine, clonazepam, phenytoin or topiramate were associated with an over 50% reduction in the seizure frequency. We plotted the receiver operating characteristic (ROC) curve for the logit(Pr) value of the model and the presence or absence of a more than 50% reduction in seizure frequency, and the areas under the curves with the 95% confidence interval from the ROC curve were 0.823 with 0.793–0.853. A logit(Pr) value of 0.1 was considered the optimal cut-off point (sensitivity = 71.8% and specificity = 80.4%), and we calculated the optimal trough concentration of VPA for each patient. Such parameters may be useful to determine the recommended therapeutic concentration of VPA for each patient, and the procedure may contribute to the further development of personalized pharmacological therapy for epilepsy. 相似文献
998.
Katayama K Shimazaki K Tazaki H Hasa Y Miyoshi M Koshino H Furuki T Nabeta K 《Bioscience, biotechnology, and biochemistry》2007,71(11):2751-2758
New clerodane-type diterpenes, designated as parvitexins A (1)-E (5), were isolated from the in vitro-cultured liverwort, Scapania parvitexta. These compounds were determined to be monoacetylated clerodane-type diterpenes based on spectroscopic evidence. 相似文献
999.
Makiko Yamashita Yoshinori Katakura Yoshihiro Aiba Shin-ei Matsumoto Kazuko Morihara Kiichiro Teruya Akira Ichikawa Sanetaka Shirahata 《Cytotechnology》2007,55(2-3):71-77
Previously, we have established an in vitro immunization method to induce antigen-specific antibody-producing B cells. In
the present study, we have attempted to clarify the mechanisms that regulate antibody production by in vitro immunized peripheral
blood mononuclear cells (PBMC). Freshly isolated PBMC did not induce antibody production following in vitro immunization,
but expressed the interleukin (IL)-10 gene. On the other hand, PBMC pretreated with l-leucyl-l-leucine methyl ester (LLME) induced antibody production, but did not express the IL-10 gene. IL-10 induced functional impairment
of CD4+ Th cells and CD11c+ DC, resulting in the suppression of antibody production by in vitro immunized PBMC. 相似文献