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1.
Mice were immunized with dengue type 2 virus (DEN 2) under a schedule favoring the production of IgE antibody. The antibody obtained could sensitize peritoneal resident mast cells both in vitro and in vivo so that the sensitized cells were degranulated and released histamine on challenge with the DEN 2 antigen. It was also demonstrated that the antibody was cytophilic and heat-labile. The above observations suggest that the present experimental system can be used to detect anti-DEN 2 IgE antibody in mice. 相似文献
2.
H Kobayashi A Inoue T Mikawa H Kuwayama Y Hotta T Masaki S Ebashi 《Journal of biochemistry》1992,112(6):786-791
Two proteins with myosin light chain kinase activity and electrophoretic molecular weights of 155,000 and 130,000 were each isolated from bovine stomach smooth muscle [Kuwayama, H., Suzuki, M., Koga, R., & Ebashi, S. (1988) J. Biochem. 104, 862-866]. The 155 kDa component showed a much higher superprecipitation-inducing activity than the 130 kDa component, when compared on the basis of equivalent myosin light chain kinase activity. In this study, we isolated a cDNA for the entire coding region of the 155 kDa protein. The deduced amino acid sequence revealed a high degree of similarity to those of chicken and rabbit smooth muscle myosin light chain kinases. Multiple motifs, such as three repeats of an immunoglobulin C2-like domain, a fibronectin type III domain, and unusual 20 repeats of 12 amino acids were detected in the sequence. Part of the amino-terminal sequence was similar to that of the actin- and calmodulin-binding domain of smooth muscle caldesmon. These observations suggest that the 155 kDa protein has additional functions other than its enzymatic activity. Two mRNAs of 6.0 and 2.6 kb in length in the bovine stomach smooth muscle RNAs were hybridized with cDNA probes. The 2.6-kb RNA probably encodes telokin, which is the carboxyl terminus of smooth muscle myosin light chain kinase. mRNAs with identical lengths were also detected in bovine aorta. 相似文献
3.
Analysis of DNA synthesis during meiotic prophase in Lilium 总被引:13,自引:0,他引:13
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We report here about an antigen that is expressed in the central nervous system (CNS) of Drosophila only during the embryonic and metamorphic stages. In Drosophila, axonogenesis and synaptogenesis occur twice during the development: first in the embryonic and second in the metamorphic stages. We generated monoclonal antibodies (MAbs) in order to obtain molecular probes for analyzing axonogenesis or synaptogenesis in the CNS on the assumption that good candidates for molecules responsible for such phenomena must be present in the neuropil during those stages exclusively. As a result, we found MAb 66B2 whose intense immunoreactivity in the neuropil of the CNS was observed exclusively in the embryo and pupa, and not in the larva and adult. Immunoblot analyses showed that MAb 66B2 binds specifically to a protein with an apparent molecular weight of 350 K and neutral pl in the prepupal CNS. A significant amount of the antigen was isolated in forms that were soluble without detergent. Results of immunohistochemistry with MAb 66B2 in a primary culture of embryos showed that some live cells in the ganglion-like cluster were stained, and that neuronal cell bodies and neurites emanating from there were negative. These results strongly suggest that the 66B2 antigen observed in the CNS is an extracellular matrix component secreted from nonneuronal cells. These developmental changes in the 66B2 immuno-reactivity in the CNS presumably reflect dynamic changes of an extracellular matrix in the CNS that are accompanied by axonogenesis or synaptogenesis. © 1992 John Wiley & Sons, Inc. 相似文献
6.
For the sensitive detection of free sugars and oligosaccharides, the use of their pyridylamino derivatives has now found general acceptance. To remove excess 2-aminopyridine from this derivative in a reaction mixture, gel filtration and ion-exchange chromatography were conducted. It was found in the present study that contaminated 2-aminopyridine could be selectively removed from the reaction mixture by adjusting the pH with saturated sodium bicarbonate at above 8.5 followed by extraction with benzene. By using this method, fewer purification steps and less time are required, with minimum loss of pyridylamino sugar derivatives. 相似文献
7.
Kazuo Imai Norihito Tarumoto Kiyoko Amo Makoto Takahashi Naoya Sakamoto Atsushi Kosaka Yasuyuki Kato Kei Mikita Jun Sakai Takashi Murakami Yutaka Suzuki Shigefumi Maesaki Takuya Maeda 《Parasitology international》2018,67(1):34-37
Cutaneous leishmaniasis (CL) is gaining attention as a public health problem. We present two cases of CL imported from Syria and Venezuela in Japan. We diagnosed them as CL non-invasively by the direct boil loop-mediated isothermal amplification method and an innovative sequencing method using the MinION? sequencer. This report demonstrates that our procedure could be useful for the diagnosis of CL in both clinical and epidemiological settings. 相似文献
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Overexpression of an Arabidopsis thaliana galactinol synthase gene improves drought tolerance in transgenic rice and increased grain yield in the field 下载免费PDF全文
Michael Gomez Selvaraj Takuma Ishizaki Milton Valencia Satoshi Ogawa Beata Dedicova Takuya Ogata Kyouko Yoshiwara Kyonoshin Maruyama Miyako Kusano Kazuki Saito Fuminori Takahashi Kazuo Shinozaki Kazuo Nakashima Manabu Ishitani 《Plant biotechnology journal》2017,15(11):1465-1477
Drought stress has often caused significant decreases in crop production which could be associated with global warming. Enhancing drought tolerance without a grain yield penalty has been a great challenge in crop improvement. Here, we report the Arabidopsis thaliana galactinol synthase 2 gene (AtGolS2) was able to confer drought tolerance and increase grain yield in two different rice (Oryza sativa) genotypes under dry field conditions. The developed transgenic lines expressing AtGolS2 under the control of the constitutive maize ubiquitin promoter (Ubi:AtGolS2) also had higher levels of galactinol than the non‐transgenic control. The increased grain yield of the transgenic rice under drought conditions was related to a higher number of panicles, grain fertility and biomass. Extensive confined field trials using Ubi:AtGolS2 transgenic lines in Curinga, tropical japonica and NERICA4, interspecific hybrid across two different seasons and environments revealed the verified lines have the proven field drought tolerance of the Ubi:AtGolS2 transgenic rice. The amended drought tolerance was associated with higher relative water content of leaves, higher photosynthesis activity, lesser reduction in plant growth and faster recovering ability. Collectively, our results provide strong evidence that AtGolS2 is a useful biotechnological tool to reduce grain yield losses in rice beyond genetic differences under field drought stress. 相似文献
10.
Koichi Shibasaki Masatoshi Kimura Ryuichi Ikarashi Akira Yamaguchi Takuya Watanabe 《Metabolomics : Official journal of the Metabolomic Society》2012,8(3):484-491
To date, few studies have examined uric acid in saliva or dental calculus. The purpose of this study is to examine the uric acid concentration in saliva and serum. Saliva and blood samples were collected from 244 participants. We divided them into four groups: untreated or treated group in normal or abnormal serum uric acid concentration groups. Within the untreated group, Pearson??s correlation coefficient was used to examine the correlation between salivary and serum uric acid concentrations. We compared uric acid concentrations between saliva and serum, or between untreated and treated groups using the paired or unpaired student??s t-test. In the untreated group, uric acid concentrations in saliva and serum were significantly and positively correlated (r?=?0.503, P?<?0.01). Within the untreated group, those with abnormal serum uric acid concentrations had significantly higher uric acid concentrations in serum and saliva compared to those with normal serum uric acid concentrations (P?<?0.01). Within the untreated group, uric acid concentrations in serum were significantly higher than that in saliva (P?<?0.01). Uric acid concentrations in saliva of the treated group were significantly higher than that of the untreated group (P?<?0.01). Within the treated group, uric acid concentrations in saliva were significantly higher than that of serum, particularly in users of benzbromarone (P?<?0.01). Uric acid concentrations in saliva were lower than that in serum among non-users of benzbromarone. In contrast, uric acid concentrations in saliva of patients taking benzbromarone were higher than that in serum. We surmise that URAT1 may influence uric acid excretion in the salivary gland. 相似文献