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981.
Tadatsu M Ito S Muguruma N Kusaka Y Inayama K Bando T Tadatsu Y Okamoto K Ii K Nagao Y Sano S Taue H 《Bioorganic & medicinal chemistry》2003,11(15):3289-3294
PURPOSE: We have developed infrared fluorescent labeling agents and infrared-ray fluorescence endoscopes to establish a novel diagnostic technique. Since the fluorescence intensity of the initial labeled antibody (ICG-sulfo-OSu-labeled antibody) was not sufficient for practical use, we synthesized indocyanine green acylthiazolidinethione (ICG-ATT), which was expected to label various target molecules having amino groups efficiently. MATERIALS AND METHODS: To confirm imaging of infrared fluorescence intensity of ICG-ATT- and ICG-sulfo-OSu-labeled anti-MUC1 antibodies, cotton thread was soaked in various concentrations of the antibody solution in 0.1M PBS, and observed under the epi-illumination infrared fluorescence microscope. Localization and the intensity of infrared fluorescence and DAB coloring was compared in paraffin sections of human gastric mucosa. RESULTS: In the study of cotton threads, both labeled antibodies showed relatively clear infrared fluorescence, and significant difference was not observed between the two antibodies. ICG-ATT-labeled anti-MUC1 antibody produced stronger staining than that by ICG-sulfo-OSu-labeled antibody. Localization pattern of infrared fluorescent staining was in good agreement with that by the conventional method with oxidized DAB staining. CONCLUSION: ICG-ATT is useful as a fluorescent-labeling agent for diagnosis of microcancers by infrared fluorescence endoscopes. 相似文献
982.
Nagamoto Kaneko You Katsuyama Kazuo Kawamura Shigeki Fujiwara 《Development, growth & differentiation》2010,52(5):457-468
The protochordate ascidian Polyandrocarpa misakiensis has a striking ability to regenerate. When the posterior half of the adult body is amputated, the anterior half completely loses the esophagus, stomach and intestine. These organs are reconstituted in a week. Histological observation revealed that the regeneration involves transdifferentiation of the atrial epithelium near the cut surface. The morphological features of the gut primordium were similar to those observed in the developing bud of this species. Inhibitors of the synthesis of retinoic acid (RA) suppressed the formation of the gut. 13‐cis RA rescued the regenerates from the inhibitor‐induced hypoplasia. These results suggest that RA is required for the regeneration of the gut. A gene encoding the RA receptor (Pm‐RAR) and its target gene, TRAMP, were expressed in and around the regenerating gut. Pm‐RAR‐specific and TRAMP‐specific double‐stranded RNA molecules inhibited the regeneration of the gut, indicating that the RA signal is mediated at least in part by Pm‐RAR and TRAMP. These results suggested that RA triggers the transdifferentiation of the atrial epithelium into the gut in regenerating animals, as it does during asexual reproduction. 相似文献
983.
Shigeki Wakamori Yoshio Yoshida Yoshio Ishii 《Bioscience, biotechnology, and biochemistry》2013,77(10):1367-1376
Several dithiocarbamates were synthesized and their herbicidal activities to radish and barnyardgrass were examined. Some benzyl N, N-dialkyldithiocarbamates such as N-methyl-N-ethyl-, N-methyl-N-n-propyl-, N, N-diethyl- and N, N-diisopropyl-dithiocarbamates showed high activity to these plants, but N-monoalkyl-, N, N-diaryl- and N, N-diaralkyl-dithio- carbamates were not so active. Some substituted benzyl N, N-dialkyldithiocarbamates such as 4-dimethylaminobenzyl N-methyl-N-ethyldithiocarbamate and 4-methoxybenzyl N, N-diethyldithiocarbamate showed high activity to broad-leaved plants. Substituted benzyl N, N-dialkyldithiocarbamates except 4-cyanobenzyl N, N-diisopropyldithiocarbamate, however, were less active to graminaceous plants. 相似文献
984.
985.
Effects of RNA interference (RNAi) targeted against circadian clock genes on two distinct types of photoperiodic responses – ovarian development and lipid accumulation – were investigated in a bean bug Riptortus pedestris, to explore which physiological process in the photoperiodic response involved the circadian clock. Ovarian development and lipid accumulation are known to be regulated by distinct output pathways. Control insects showed clear photoperiodic responses; i.e. induction of ovarian development and suppression of lipid accumulation under long-day conditions, whereas opposite characteristics under short-day conditions. We found that RNAi directed against period, a negative element of the circadian clock, produced a long-day effect for both the ovarian development and lipid accumulation, while RNAi directed against Clock, a positive element of the circadian clock, produced a short-day effect for both, irrespective of photoperiod. These results indicate that the circadian clock comprised of these genes regulates a process governing both distinct photoperiodic responses. 相似文献
986.
Ikuko Nakajima Akiko Ito Shigeki Moriya Toshihiro Saito Takaya Moriguchi Toshiya Yamamoto 《In vitro cellular & developmental biology. Plant》2012,48(4):396-402
An efficient method for the generation of adventitious shoots from the cotyledons of Japanese pear and related species was developed. Cotyledons from seeds of the Japanese pear ??Okusankichi?? and the Asian pea pear ??Hokushimamenashi?? were used to determine the optimum concentrations of phytohormones in the medium. The rates of generation of adventitious shoots and the numbers of adventitious shoots per explant were highest when the media contained 5???M 1-naphthaleneacetic acid combined with 10 or 25???M 6-benzylaminopurine. These growth regulators were used to generate adventitious shoots from the cotyledons of 33 cultivars of Japanese, Chinese, Asian pea, and European pears. A high number of adventitious shoots per explant (1.3?C2.3) and high rates of regeneration of adventitious shoots (60?C76?%) were obtained from the cotyledons of Japanese pears ??Imamuraaki?? and ??Agenosho Shinanashi.?? Although pollination was not controlled, cotyledons from mother trees of old Japanese cultivars and Chinese pears tended to be more regenerable than those from other pear species. Since the rooting ability of the adventitious shoots was very low, micro-grafting was applied to obtain regenerated potted plants from adventitious shoots. Grafted regenerated plants were recovered at a rate of more than 60?%, regardless of cultivar. To our knowledge, this is the first report to evaluate shoot regeneration from cotyledons of major Pyrus species. 相似文献
987.
Hiromitsu Ito Shinji Tanaka Yoshimitsu Akiyama Shu Shimada Rama Adikrisna Satoshi Matsumura Arihiro Aihara Yusuke Mitsunori Daisuke Ban Takanori Ochiai Atsushi Kudo Shigeki Arii Shoji Yamaoka Minoru Tanabe 《PloS one》2016,11(1)
Patients with pancreatic cancer typically develop tumor invasion and metastasis in the early stage. These malignant behaviors might be originated from cancer stem cells (CSCs), but the responsible target is less known about invisible CSCs especially for invasion and metastasis. We previously examined the proteasome activity of CSCs and constructed a real-time visualization system for human pancreatic CSCs. In the present study, we found that CSCs were highly metastatic and dominantly localized at the invading tumor margins in a liver metastasis model. Microarray and siRNA screening assays showed that doublecortin-like kinase 1 (DCLK1) was predominantly expressed with histone modification in pancreatic CSCs with invasive and metastatic potential. Overexpression of DCLK1 led to amoeboid morphology, which promotes the migration of pancreatic cancer cells. Knockdown of DCLK1 profoundly suppressed in vivo liver metastasis of pancreatic CSCs. Clinically, DCLK1 was overexpressed in the metastatic tumors in patients with pancreatic cancer. Our studies revealed that DCLK1 is essential for the invasive and metastatic properties of CSCs and may be a promising epigenetic and therapeutic target in human pancreatic cancer. 相似文献
988.
989.
K. Moriguchi N. Higuchi Y. Murakami F. Yoshimura H. Nakamura N. Ohno 《Biotechnic & histochemistry》2003,78(2):129-133
We used a rapid freezing and freeze-substitution technique without glutaraldehyde and OsO4 fixation for the electron microscopic immunocytochemical demonstration of the surface structure of Bacteroides forsythus, an anaerobic Gram-negative periodontopathogen. Cells were applied to pieces of filter paper and freeze-substituted by plunge-freezing in liquid propane, substituted in methanol containing 0.5% uranyl acetate, and infiltrated with LR White resin. The membrane ultrastructure of B. forsythus was preserved well, and the labeling density of the freeze-submitted cells was compared to a conventional processing method. Our results show the usefulness of the freeze-substitution method for immunohistochemical studies of B. forsythus. 相似文献
990.
Shinri Horoiwa Taiyo Yokoi Satoru Masumoto Saki Minami Chiharu Ishizuka Hidetoshi Kishikawa Shunsuke Ozaki Shigeki Kitsuda Yoshiaki Nakagawa Hisashi Miyagawa 《Bioorganic & medicinal chemistry》2019,27(6):1065-1075
The ecdysone receptor (EcR) is an insect nuclear receptor that is activated by the molting hormone, 20-hydroxyecdysone. Because synthetic EcR ligands disrupt the normal growth of insects, they are attractive candidates for new insecticides. In this study, the Molecular Mechanics/Poisson–Boltzmann Surface Area (MM/PBSA) method was used to predict the binding activity of EcR ligands. Validity analyses using 40 known EcR ligands showed that the binding activity was satisfactorily predicted when the ligand conformational free energy term was introduced. Subsequently, this MM/PBSA method was applied to structure-based hierarchical virtual screening, and 12 candidate compounds were selected from a database of 3.8 million compounds. Five of these compounds were active in a cell-based competitive binding assay. The most potent compound is a simple proline derivative with low micromolar binding activity, representing a valuable lead compound for further structural optimization. 相似文献