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81.
Yukiko Kawanabe Hisakazu Yamane Nobutaka Takahashi Teruko Nakamura 《Bioscience, biotechnology, and biochemistry》2013,77(8):2447-2450
GA3 was identified as a major GA in Neurospora crassa by gas chromatography/selected ion monitoring (GC/SIM) and its content was measured at various stages (0~96 hr after inoculation) of conidial germination and mycelial growth. The GA3 content in the fungus was 190ng/g dry weight at the initial stage and then decreased rapidly; that per liter culture decreased soon after the inoculation, and then increased to 17.6 ng 96 hr after inoculation. The GA3 concentration in the culture medium was around 10?11 m throughout the 96-hr incubation. The physiological role of endogenous GA in Neurospora crassa is also discussed. 相似文献
82.
Ki-Sung Kim Yuichiro Arima Taro Kitazawa Koichi Nishiyama Rieko Asai Yasunobu Uchijima Takahiro Sato Giovanni Levi Sachiko Kitanaka Takashi Igarashi Yukiko Kurihara Hiroki Kurihara 《Mechanisms of development》2013,130(11-12):553-566
Endothelin-1 (Edn1), originally identified as a vasoconstrictor peptide, is involved in the development of cranial/cardiac neural crest-derived tissues and organs. In craniofacial development, Edn1 binds to Endothelin type-A receptor (Ednra) to induce homeobox genes Dlx5/Dlx6 and determines the mandibular identity in the first pharyngeal arch. However, it remains unsolved whether this pathway is also critical for pharyngeal arch artery development to form thoracic arteries. Here, we show that the Edn1/Ednra signaling is involved in pharyngeal artery development by controlling the fate of neural crest cells through a Dlx5/Dlx6-independent mechanism. Edn1 and Ednra knock-out mice demonstrate abnormalities in pharyngeal arch artery patterning, which include persistent first and second pharyngeal arteries, resulting in additional branches from common carotid arteries. Neural crest cell labeling with Wnt1-Cre transgene and immunostaining for smooth muscle cell markers revealed that neural crest cells abnormally differentiate into smooth muscle cells at the first and second pharyngeal arteries of Ednra knock-out embryos. By contrast, Dlx5/Dlx6 knockout little affect the development of pharyngeal arch arteries and coronary arteries, the latter of which is also contributed by neural crest cells through an Edn-dependent mechanism. These findings indicate that the Edn1/Ednra signaling regulates neural crest differentiation to ensure the proper patterning of pharyngeal arch arteries, which is independent of the regional identification of the pharyngeal arches along the dorsoventral axis mediated by Dlx5/Dlx6. 相似文献
83.
Effects of lactoferrin and lactoperoxidase‐containing food on the oral microbiota of older individuals 下载免费PDF全文
Manabu Nakano Hiroyuki Wakabayashi Hirosuke Sugahara Toshitaka Odamaki Koji Yamauchi Fumiaki Abe Jin‐Zhong Xiao Kohji Murakami Kentaro Ishikawa Shouji Hironaka 《Microbiology and immunology》2017,61(10):416-426
84.
Ishikawa Keiko; Kamada Hiroshi; Yamaguchi Isomaro; Takahashi Nobutaka; Harada Hiroshi 《Plant & cell physiology》1988,29(3):461-466
Carrot and tobacco plants were transformed with Agrobacteriumtumefaciens harboring wild-type, aux or cyt Tiplasmids. In tobacco, these wild and mutant Ti plasmids inducedthe formation of non-morphogenic galls, galls with shoots, andgalls with roots, respectively. In carrot, however, transformationwith any of these plasmids resulted in only the formation ofamorphous tumors. Determination of IAA and cytokinin contentsshowed that in tobacco, significantly high amounts of cytokininsor IAA are present in the cells transformed with Ti plasmidspossessing cytokinin or IAA biosynthetic genes, respectively.In carrot, cytokinin contents were also high in the cells transformedwith Ti plasmids having cytokinin biosynthetic genes, whereasIAA contents of the cells were similar regardless of the plasmidsused for transformation. These results suggest that the mechanism regulating IAA metabolismmay be different in tobacco and carrot. (Received June 25, 1987; Accepted February 1, 1988) 相似文献
85.
IAA biosynthetic activity was examined in cultured carrot tissuestransformed with Agrobacterium tumefaciens harboring wild-type,aux or cyt Ti plasmids. In vitro IAAM hydrolaseactivities in tissues transformed with wild-type, and cytTi plasmids were 3.09 and 19.82 nmol/g proteins/30 min, respectively,but not detectable when aux Ti plasmids were used. Theactivity of IAA biosynthesis, determined by the incorporationof radioactivity into IAA in tissues fed with [14C]-tryptophan,was 34.13, 10.92 and 32.47 pmol/g fr wt/30 min in tissues transformedwith wild type, aux and cyt Ti plasmids, respectively.The incorporation of radioactivity into the IAAM fraction wasdetected only in the tissues transformed with wild type andcyt Ti plasmids. These results showed that the T-DNAencoded pathway of IAA biosynthesis was active in tissues transformedwith wild-type and cyth Ti plasmids, and that the activity ofIAA biosynthesis in those tissues was higher than that in tissuestransformed with the aux Ti plasmid. (Received March 16, 1988; Accepted July 31, 1988) 相似文献
86.
Yukiko Matsuo Tsutomu Ishihara Ken-ichi Miyamoto Naomi Yamashita 《Cellular immunology》2009,260(1):33-38
Although inhaled steroids are the treatment of first choice to control asthma, administration of systemic steroids is required for treatment of asthmatic exacerbation and intractable asthma. To improve efficacy and reduce side effects, we examine the effects of betamethasone disodium phosphate (BP) encapsulated in biocompatible, biodegradable blended nanoparticles (stealth nanosteroids) on a murine model of asthma. These stealth nanosteroids were found to accumulate at the site of airway inflammation and exhibit anti-inflammatory activity. Significant decreases in BALF eosinophil number were maintained for 7 days with a single injection of nanosteroids containing 40 μg BP. Airway responsiveness was also attenuated by the injection of stealth nanosteroids. A single injection of 40 μg of free BP and 8 μg of free BP once daily for 5 days did not show any significant effects. We conclude that stealth nanosteroids achieve prolonged and higher benefits at the site of airway inflammation compared to free steroids. 相似文献
87.
Tomoya Matsunobu Kiyoyuki Torigoe Masaki Ishikawa Ashok B. Kulkarni Yoshihiko Yamada 《Developmental biology》2009,332(2):325-338
TGF-β has been implicated in the proliferation and differentiation of chondrocytes and osteoblasts. However, the in vivo function of TGF-β in skeletal development is unclear. In this study, we investigated the role of TGF-β signaling in growth plate development by creating mice with a conditional knockout of the TGF-β type I receptor ALK5 (ALK5CKO) in skeletal progenitor cells using Dermo1-Cre mice. ALK5CKO mice had short and wide long bones, reduced bone collars, and trabecular bones. In ALK5CKO growth plates, chondrocytes proliferated and differentiated, but ectopic cartilaginous tissues protruded into the perichondrium. In normal growth plates, ALK5 protein was strongly expressed in perichondrial progenitor cells for osteoblasts, and in a thin chondrocyte layer located adjacent to the perichondrium in the peripheral cartilage. ALK5CKO growth plates had an abnormally thin perichondrial cell layer and reduced proliferation and differentiation of osteoblasts. These defects in the perichondrium likely caused the short bones and ectopic cartilaginous protrusions. Using tamoxifen-inducible Cre-ER™-mediated ALK5-deficient primary calvarial cell cultures, we found that TGF-β signaling promoted osteoprogenitor proliferation, early differentiation, and commitment to the osteoblastic lineage through the selective MAPKs and Smad2/3 pathways. These results demonstrate the important roles of TGF-β signaling in perichondrium formation and differentiation, as well as in growth plate integrity during skeletal development. 相似文献
88.
Matsuki N Ichiba S Ishikawa T Nagano O Takeda M Ujike Y Yamaguchi T 《European biophysics journal : EBJ》2012,41(6):571-578
Microbubbles have been used in a variety of fields and have unique properties, for example shrinking collapse, long lifetime, efficient gas solubility, a negatively charged surface, and the ability to produce free radicals. In medicine, microbubbles have been used mainly as diagnostic aids to scan various organs of the body, and they have recently been investigated for use in drug and gene delivery. However, there have been no reports of blood oxygenation by use of oxygen microbubble fluids without shell reagents. In this study, we demonstrated that nano or microbubbles can achieve oxygen supersaturation of fluids, and may be sufficiently small and safe for infusion into blood vessels. Although Po(2) increases in fluids resulting from use of microbubbles were inhibited by polar solvents, normal saline solution (NSS) was little affected. Thus, NSS is suitable for production of oxygen-rich fluid. In addition, oxygen microbubble NSS effectively improved hypoxic conditions in blood. Thus, use of oxygen microbubble (nanobubble) fluids is a potentially effective novel method for oxygenation of hypoxic tissues, for infection control, and for anticancer treatment. 相似文献
89.
Summary All aphids harbor symbiotrophic prokaryotes (primary symbionts) in a specialized-abdominal cell, the bacteriocyte. Chaperonin 60 (Cpn60, symbionin) and chaperonin 10 (Cpn10), which are high and low molecular weight heatshock proteins, were sought in tissues of more than 60 aphid species. The endosymbionts were compared immunologically and histologically. It was demonstrated that (1) there are two types of aphids in terms of the endosymbiotic system: some with only primary symbionts and others with, in addition, secondary symbionts; (2) the primary symbionts of various aphids are quite similar in morphology whereas the secondary symbionts vary; and (3) irrespective of the aphid species, Cpn60 is abundant in both the primary and secondary symbionts, while Cpn10 is abundant in the secondary symbionts but present in small amounts in the primary ones. Based on these results, we suggest that the primary symbionts have been derived from a prokaryote that was acquired by the common ancestor of aphids whereas the secondary symbionts have been acquired by various aphids independently after divergence of the aphid species. In addition, we point out the possibility that the prokaryotes under intracellular conditions have been subject to some common evolutionary pressures, and as a result, have come to resemble cell organelles. 相似文献
90.