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81.
82.
It is possible to determine the sequence of a dipeptide containing glutamic acid as a constituent and also to decide whether the glutamyl bond is α or γ when glutamic acid is the N-terminal component by measuring the NMR spectra of the peptide in acidic, aqueous and basic solutions. 相似文献
83.
Hiroyoshi Yamauchi Masashi Bando Tomohisa Baba Kensuke Kataoka Yoshihito Yamada Hiroshi Yamamoto Atsushi Miyamoto Soichiro Ikushima Takeshi Johkoh Fumikazu Sakai Yasuhiro Terasaki Akira Hebisawa Yoshinori Kawabata Yukihiko Sugiyama Takashi Ogura 《PloS one》2016,11(11)
Some patients with idiopathic pulmonary fibrosis (IPF) do not have honeycombing on high-resolution computed tomography (HRCT) at their initial evaluation. The clinical course and sequential changes in HRCT findings in these patients are not fully understood. We reviewed the cases of 43 patients with IPF without honeycombing on initial HRCT from institutions throughout Japan. All patients were diagnosed with IPF based on a surgical lung biopsy. Multidisciplinary discussions were held five times between 2011 and 2014, to exclude alternative etiologies. We evaluated the sequential changes in HRCT findings in 30 patients with IPF. We classified these 30 patients into three groups based on their HRCT patterns and clarified the clinical characteristics and prognosis among the groups. The patterns of all 30 patients on initial HRCT corresponded to a possible usual interstitial pneumonia (UIP) pattern which was described in the 2011 International Statement. On long-term follow-up (71.0±38.7 standard deviation [SD] months), honeycombing was seen in 16 patients (53%, the HoneyCo group); traction bronchiectasis or cysts without honeycombing was observed in 12 patients (40%, the NoHoneyCo group), and two patients showed no interval change (7%, the NoChange group) on HRCT. The mean survival periods of the HoneyCo and NoHoneyCo groups were 67.1 and 61.2 months, respectively (p = 0.76). There are some patients with IPF whose conditions chronically progress without honeycombing on HRCT. The appearance of honeycombing on HRCT during the follow-up might not be related to prognosis. 相似文献
84.
Takashi Kasai Takahiko Tokuda Takuma Ohmichi Ryotaro Ishii Harutsugu Tatebe Masanori Nakagawa Toshiki Mizuno 《PloS one》2016,11(1)
The COQ2 gene encodes an essential enzyme for biogenesis, coenzyme Q10 (CoQ10). Recessive mutations in this gene have recently been identified in families with multiple system atrophy (MSA). Moreover, specific heterozygous variants in the COQ2 gene have also been reported to confer susceptibility to sporadic MSA in Japanese cohorts. These findings have suggested the potential usefulness of CoQ10 as a blood-based biomarker for diagnosing MSA. This study measured serum levels of CoQ10 in 18 patients with MSA, 20 patients with Parkinson’s disease and 18 control participants. Although differences in total CoQ10 (i.e., total levels of serum CoQ10 and its reduced form) among the three groups were not significant, total CoQ10 level corrected by serum cholesterol was significantly lower in the MSA group than in the Control group. Our findings suggest that serum CoQ10 can be used as a biomarker in the diagnosis of MSA and to provide supportive evidence for the hypothesis that decreased levels of CoQ10 in brain tissue lead to an increased risk of MSA. 相似文献
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Stphanie Sherpa Maya Guguen Julien Renaud Michael G. B. Blum Thierry Gaude Frdric Laporte Mustafa Akiner Bulent Alten Carles Aranda Hlne Barre‐Cardi Romeo Bellini Mikel Bengoa Paulis Xiao‐Guang Chen Roger Eritja Eleonora Flacio Cipriano Foxi Intan H. Ishak Katja Kalan Shinji Kasai Fabrizio Montarsi Igor Pajovi Duan Petri Rosa Termine Nataa Turi Gonzalo M. Vazquez‐Prokopec Enkelejda Velo Goran Vignjevi Xiaohong Zhou Laurence Desprs 《Ecology and evolution》2019,9(22):12658-12675
Invasive species can encounter environments different from their source populations, which may trigger rapid adaptive changes after introduction (niche shift hypothesis). To test this hypothesis, we investigated whether postintroduction evolution is correlated with contrasting environmental conditions between the European invasive and source ranges in the Asian tiger mosquito Aedes albopictus. The comparison of environmental niches occupied in European and source population ranges revealed more than 96% overlap between invasive and source niches, supporting niche conservatism. However, we found evidence for postintroduction genetic evolution by reanalyzing a published ddRADseq genomic dataset from 90 European invasive populations using genotype–environment association (GEA) methods and generalized dissimilarity modeling (GDM). Three loci, among which a putative heat‐shock protein, exhibited significant allelic turnover along the gradient of winter precipitation that could be associated with ongoing range expansion. Wing morphometric traits weakly correlated with environmental gradients within Europe, but wing size differed between invasive and source populations located in different climatic areas. Niche similarities between source and invasive ranges might have facilitated the establishment of populations. Nonetheless, we found evidence for environmental‐induced adaptive changes after introduction. The ability to rapidly evolve observed in invasive populations (genetic shift) together with a large proportion of unfilled potential suitable areas (80%) pave the way to further spread of Ae. albopictus in Europe. 相似文献
88.
Freeze-dried platelets promote hepatocyte proliferation in mice 总被引:1,自引:0,他引:1
Hoshi R Murata S Matsuo R Myronovych A Hashimoto I Ikeda H Ohkohchi N 《Cryobiology》2007,55(3):255-260
In recent years, platelets are reported to promote liver, as well as bone regeneration and dermal wound healing. Platelets are required not only for thrombocytopenia treating but also for regenerative therapy. Platelets cannot be stored beyond three days, therefore, shortage of fresh platelets sometimes occurs. To preserve platelets for a long duration without degrading growth factors, a freeze-dried technique is required. We report here that platelets can be preserved by freeze-drying, using a programmed freezing method to avoid intracellular ice crystal formation. Freeze-dried platelets kept their morphological countenance and response with the agonist of thrombin was well maintained. Freeze-dried platelets stored adenine nucleotides, PDGF, and IGF-1 the same as those of fresh platelets. Freeze dried platelets also preserved their proliferative effect on hepatocytes identical to that of fresh platelets. These results of our study suggest that freeze dried platelets will obviate the storage problem of fresh platelets. 相似文献
89.
Stable integration and conditional expression of electroporated transgenes in chicken embryos 总被引:2,自引:0,他引:2
Sato Y Kasai T Nakagawa S Tanabe K Watanabe T Kawakami K Takahashi Y 《Developmental biology》2007,305(2):616-624
The in ovo electroporation in chicken embryos has widely been used as a powerful tool to study roles of genes during embryogenesis. However, the conventional electroporation technique fails to retain the expression of transgenes for more than several days because transgenes are not integrated into the genome. To overcome this shortcoming, we have developed a transposon-mediated gene transfer, a novel technique in chicken manipulations. It was previously reported that the transposon Tol2, originally found in medaka fish, facilitates an integration of a transgene into the genome when co-acting with Tol2 transposase. In this study, we co-electroporated a plasmid containing a CAGGS-EGFP cassette cloned in the Tol2 construct along with a transposase-encoding plasmid into early presomitic mesoderm or optic vesicles of chicken embryos. This resulted in persistent expression of EGFP at least until embryonic day 8 (E8) and E12 in somite-derived tissues and developing retina, respectively. The integration of the transgene was confirmed by genomic Southern blotting using chicken cultured cells. We further combined this transposon-mediated gene transfer with the tetracycline-dependent conditional expression system that we also developed recently. With this combined method, expression of a stably integrated transgene could be experimentally induced upon tetracycline administration at relatively late stages such as E6, where a variety of organogenesis are underway. Thus, the techniques proposed in this study provide a novel approach to study the mechanisms of late organogenesis, for which chickens are most suitable model animals. 相似文献
90.
Takano Y Yamauchi K Hayakawa K Hiramatsu N Kasai A Okamura M Yokouchi M Shitamura A Yao J Kitamura M 《FEBS letters》2007,581(3):421-426
Expression of nephrin, a crucial component of the glomerular slit diaphragm, is downregulated in patients with proteinuric glomerular diseases. Using conditionally immortalized reporter podocytes, we found that bystander macrophages as well as macrophage-derived cytokines IL-1beta and TNF-alpha markedly suppressed activity of the nephrin gene promoter in podocytes. The cytokine-initiated repression was reversible, observed on both basal and inducible expression, independent of Wilms' tumor suppressor WT1, and caused in part via activation of the phosphatidylinositol-3-kinase/Akt pathway. These results indicated a novel mechanism by which activated macrophages participate in the induction of proteinuria in glomerular diseases. 相似文献