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101.
Takanori Kasai Minoru Sano Sadao Sakamura 《Bioscience, biotechnology, and biochemistry》2013,77(12):2449-2453
l-Ng-Methylarginine, l-Ng,Ng-dimethylarginine and ethanolamine were isolated from basic amino acids fraction of broad bean (Vicia faba L.) seed. The presence of Ng,N′g-dimethylarginine was also suggested. 相似文献
102.
Caffeine (1,3,7-trimethixanthine) is a typical purine alkaloid produced in more than 80 plant species. Its biological role is considered to strengthen plant''s defense capabilities, directly as a toxicant to biotic attackers (allelopathy) and indirectly as an activator of defense system (priming). Caffeine is actively secreted into rhizosphere through primary root, and possibly affects the structure of microbe community nearby. The fungal community in coffee plant rhizosphere is enriched with particular species, including Trichoderma family, a mycoparasite that attacks and kills phytopathogens by coiling and destroying their hyphae. In the present study, the caffeine response of 8 filamentous fungi, 4 mycoparasitic Trichoderma, and 4 prey phytopathogens, was examined. Results showed that allelopathic effect of caffeine on fungal growth and development was differential, being stronger on pathogens than on Trichoderma species. Upon confronting, the prey immediately ceased the growth, whereas the predator continued to grow, indicating active mycoparasitism to have occurred. Caffeine enhanced mycoparasitism up to 1.7-fold. Caffeine thus functions in a double-track manner against fungal pathogens: first by direct suppression of growth and development, and second by assisting their natural enemy. These observations suggest that caffeine is a powerful weapon in the arms race between plants and pathogens by fostering enemy''s enemy, and we propose the idea of "caffeine fostering" as the third role of caffeine. 相似文献
103.
Background
In mathematical epidemiology, age-structured epidemic models have usually been formulated as the boundary-value problems of the partial differential equations. On the other hand, in engineering, the backstepping method has recently been developed and widely studied by many authors.Methods
Using the backstepping method, we obtained a boundary feedback control which plays the role of the threshold criteria for the prediction of increase or decrease of newly infected population. Under an assumption that the period of infectiousness is same for all infected individuals (that is, the recovery rate is given by the Dirac delta function multiplied by a sufficiently large positive constant), the prediction method is simplified to the comparison of the numbers of reported cases at the current and previous time steps.Results
Our prediction method was applied to the reported cases per sentinel of influenza in Japan from 2006 to 2015 and its accuracy was 0.81 (404 correct predictions to the total 500 predictions). It was higher than that of the ARIMA models with different orders of the autoregressive part, differencing and moving-average process. In addition, a proposed method for the estimation of the number of reported cases, which is consistent with our prediction method, was better than that of the best-fitted ARIMA model ARIMA(1,1,0) in the sense of mean square error.Conclusions
Our prediction method based on the backstepping method can be simplified to the comparison of the numbers of reported cases of the current and previous time steps. In spite of its simplicity, it can provide a good prediction for the spread of influenza in Japan.104.
Yoshiko Onda Rimei Nishimura Aya Morimoto Hironari Sano Kazunori Utsunomiya Naoko Tajima The Diabetes Epidemiology Research International Mortality Study Group 《PloS one》2016,11(3)
Objective
To follow up Japanese patients with type 1 diabetes for a maximum of 40 years to examine when they transitioned from pediatric care to adult care and to explore whether the attending physician, i.e., pediatrician or internist, was associated with prognosis.Methods
Participants consisted of 1,299 patients who had been diagnosed as having type 1 diabetes at less than 15 years old between 1965 and 1979 identified through two nationwide surveys. Patients were classified as having received either pediatric care or adult care at the age of 15 and 30, and were compared for differences in mortality associated with the attending physician.Results
The attending physicians were confirmed for a total of 1,093 patients at the age of 15. Of these patients, 43.8% and 40.3% received pediatric care and adult care, respectively. Of the 569 patients receiving pediatric care, 74.2%, 56.6%, 53.4%, and 51.3% continued with pediatric care at 20, 30, 40, and 50 years old, respectively. The attending physicians (pediatrician or internist) at the age of 15 and 30 had no significant impact on their survival (P = 0. 892, 0.411, respectively).Conclusions
More than half of the patients who had received pediatric care at the age of 15 continued to receive pediatric care even after the age of 30, suggesting that their transition was far from smooth, while the attending physician at the age of both 15 and 30 was not a prognostic factor for mortality. Thus, the timing for transition to adult care in these patients has no relationship with mortality in Japan. 相似文献105.
Youichi Suzuki Wei-Xin Chin Qi'En Han Koji Ichiyama Ching Hua Lee Zhi Wen Eyo Hirotaka Ebina Hirotaka Takahashi Chikako Takahashi Beng Hui Tan Takayuki Hishiki Kenji Ohba Toshifumi Matsuyama Yoshio Koyanagi Yee-Joo Tan Tatsuya Sawasaki Justin Jang Hann Chu Subhash G. Vasudevan Kouichi Sano Naoki Yamamoto 《PLoS pathogens》2016,12(1)
Dengue virus (DENV) is one of the most important arthropod-borne pathogens that cause life-threatening diseases in humans. However, no vaccine or specific antiviral is available for dengue. As seen in other RNA viruses, the innate immune system plays a key role in controlling DENV infection and disease outcome. Although the interferon (IFN) response, which is central to host protective immunity, has been reported to limit DENV replication, the molecular details of how DENV infection is modulated by IFN treatment are elusive. In this study, by employing a gain-of-function screen using a type I IFN-treated cell-derived cDNA library, we identified a previously uncharacterized gene, C19orf66, as an IFN-stimulated gene (ISG) that inhibits DENV replication, which we named Repressor of yield of DENV (RyDEN). Overexpression and gene knockdown experiments revealed that expression of RyDEN confers resistance to all serotypes of DENV in human cells. RyDEN expression also limited the replication of hepatitis C virus, Kunjin virus, Chikungunya virus, herpes simplex virus type 1, and human adenovirus. Importantly, RyDEN was considered to be a crucial effector molecule in the IFN-mediated anti-DENV response. When affinity purification-mass spectrometry analysis was performed, RyDEN was revealed to form a complex with cellular mRNA-binding proteins, poly(A)-binding protein cytoplasmic 1 (PABPC1), and La motif-related protein 1 (LARP1). Interestingly, PABPC1 and LARP1 were found to be positive modulators of DENV replication. Since RyDEN influenced intracellular events on DENV replication and, suppression of protein synthesis from DENV-based reporter construct RNA was also observed in RyDEN-expressing cells, our data suggest that RyDEN is likely to interfere with the translation of DENV via interaction with viral RNA and cellular mRNA-binding proteins, resulting in the inhibition of virus replication in infected cells. 相似文献
106.
Osamu Nunobiki Daisuke Sano Kyoko Akashi Taro Higashida Toshitada Ogasawara Hikari Akise Shinji Izuma Kiyo Torii Yoshiaki Okamoto Ichiro Tanaka Masatsugu Ueda 《Human cell》2016,29(2):91-95
To investigate the clinical significance of ALDH2 genetic polymorphisms in cervical carcinogenesis. ALDH2 polymorphisms together with human papillomavirus (HPV) types were examined in a total of 195 cervical smear in exfoliated cervical cell samples using Real-Time polymerase chain reaction (PCR) System. The frequency for the AG+AA genotype was seven in the normal group (70.0 %), 16 in the LSIL group (57.1 %), and 27 in the HSIL group (90.0 %). A significant difference was found between the LSIL and HSIL groups (P = 0.0064). Patients with HSIL lesions frequently had high-risk HPV infections and concurrently belonged to the AG+AA group. ALDH2 genotype in cervical cell samples may be associated with more severe precancerous lesions of the cervix in a Japanese population. 相似文献
107.
Naohiro Yoshida Jin Endo Kenichiro Kinouchi Hiroki Kitakata Hidenori Moriyama Masaharu Kataoka Tsunehisa Yamamoto Kohsuke Shirakawa Satoshi Morimoto Akira Nishiyama Akihiro Hashiguchi Itsuro Higuchi Keiichi Fukuda Atsuhiro Ichihara Motoaki Sano 《Aging cell》2019,18(5)
To extend life expectancy and ensure healthy aging, it is crucial to prevent and minimize age‐induced skeletal muscle atrophy, also known as sarcopenia. However, the disease's molecular mechanism remains unclear. The age‐related Wnt/β‐catenin signaling pathway has been recently shown to be activated by the (pro)renin receptor ((P)RR). We report here that (P)RR expression was increased in the atrophied skeletal muscles of aged mice and humans. Therefore, we developed a gain‐of‐function model of age‐related sarcopenia via transgenic expression of (P)RR under control of the CAG promoter. Consistent with our hypothesis, (P)RR‐Tg mice died early and exhibited muscle atrophy with histological features of sarcopenia. Moreover, Wnt/β‐catenin signaling was activated and the regenerative capacity of muscle progenitor cells after cardiotoxin injury was impaired due to cell fusion failure in (P)RR‐Tg mice. In vitro forced expression of (P)RR protein in C2C12 myoblast cells suppressed myotube formation by activating Wnt/β‐catenin signaling. Administration of Dickkopf‐related protein 1, an inhibitor of Wnt/β‐catenin signaling, and anti‐(P)RR neutralizing antibody, which inhibits binding of (P)RR to the Wnt receptor, significantly improved sarcopenia in (P)RR‐Tg mice. Furthermore, the use of anti‐(P)RR neutralizing antibodies significantly improved the regenerative ability of skeletal muscle in aged mice. Finally, we show that Yes‐associated protein (YAP) signaling, which is coordinately regulated by Wnt/β‐catenin, contributed to the development of (P)RR‐induced sarcopenia. The present study demonstrates the use of (P)RR‐Tg mice as a novel sarcopenia model, and shows that (P)RR‐Wnt‐YAP signaling plays a pivotal role in the pathogenesis of this disease. 相似文献
108.
Yoshikazu Furusawa Shinji Yamada Shunsuke Itai Takuro Nakamura Miyuki Yanaka Masato Sano Hiroyuki Harada Masato Fukui Mika K. Kaneko Yukinari Kato 《Biochemistry and Biophysics Reports》2019
Monoclonal antibodies (mAbs) against human, mouse, rat, rabbit, dog, cat, and bovine podoplanin (PDPN), a lymphatic endothelial cell marker, have been established in our previous studies. However, mAbs against horse PDPN (horPDPN), which are useful for immunohistochemical analysis, remain to be developed. In the present study, mice were immunized with horPDPN-overexpressing Chinese hamster ovary (CHO)-K1 cells (CHO/horPDPN), and hybridomas producing mAbs against horPDPN were screened using flow cytometry. One of the mAbs, PMab-219 (IgG2a, kappa), specifically detected CHO/horPDPN cells via flow cytometry and recognized horPDPN protein using Western blotting. Furthermore, PMab-219 strongly stained CHO/horPDPN via immunohistochemistry. These findings suggest that PMab-219 is useful for investigating the function of horPDPN. 相似文献
109.
Yukinari Kato Yoshikazu Furusawa Shinji Yamada Shunsuke Itai Junko Takei Masato Sano Mika K. Kaneko 《Biochemistry and Biophysics Reports》2019
Podoplanin (PDPN) is known as a lymphatic endothelial cell marker. Monoclonal antibodies (mAbs) against human, mouse, rat, rabbit, dog, cat, bovine, pig, and horse PDPN have been established in our previous studies. However, mAbs against alpaca PDPN (aPDPN), required for immunohistochemical analysis, remain to be developed. In the present study, we employed the Cell-Based Immunization and Screening (CBIS) method for producing anti-aPDPN mAbs. We immunized mice with aPDPN-overexpressing Chinese hamster ovary (CHO)-K1 cells (CHO/aPDPN), and hybridomas producing mAbs against aPDPN were screened using flow cytometry. One of the mAbs, PMab-225 (IgG2b, kappa), specifically detected CHO/aPDPN cells via flow cytometry and recognized the aPDPN protein on Western blotting. Further, PMab-225 strongly stained lung type I alveolar cells, colon lymphatic endothelial cells, and kidney podocytes via immunohistochemistry. These findings demonstrate that PMab-225 antibody is useful to investigate the function of aPDPN via different techniques. 相似文献
110.
Yoshikazu Furusawa Shinji Yamada Shunsuke Itai Takuro Nakamura Junko Takei Masato Sano Hiroyuki Harada Masato Fukui Mika K. Kaneko Yukinari Kato 《Biochemistry and Biophysics Reports》2019
Monoclonal antibodies (mAbs) against not only human, mouse, and rat but also rabbit, dog, cat, bovine, pig, and horse podoplanins (PDPNs) have been established in our previous studies. PDPN is used as a lymphatic endothelial cell marker in pathological diagnoses. However, mAbs against Tasmanian devil PDPN (tasPDPN), which are useful for immunohistochemical analysis, remain to be developed. Herein, mice were immunized with tasPDPN-overexpressing Chinese hamster ovary (CHO)-K1 (CHO/tasPDPN) cells, and hybridomas producing mAbs against tasPDPN were screened using flow cytometry. One of the mAbs, PMab-233 (IgG1, kappa), specifically detected CHO/tasPDPN cells by flow cytometry and recognized tasPDPN protein by western blotting. Furthermore, PMab-233 strongly detected CHO/tasPDPN cells by immunohistochemistry. These findings suggest that PMab-233 may be useful as a lymphatic endothelial cell marker of the Tasmanian devil. 相似文献