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101.
Takimoto Atsushi; Kaihara Sumiko; Shinozaki Masateru; Miura Junkichi 《Plant & cell physiology》1991,32(2):283-289
A flower-inducing substance (FIS) is produced by incubationof the pellet of centrifuged ho-mogenates of Lemna paucicostata441 (P441) with commercial enzyme preparations such as catalase,cellulase, lipase and proteinase K. The active component inthese preparations was identified as tyrosine. The tyrosinemetabolites, dopa, dopamine, norepinephrine (NE) and epinephrine,were also effective for the production of FIS, and NE the mosteffective. Addition of only 1 µg NE to the pellet obtainedfrom 100 mg fresh weight of P441 produced FIS without incubation.NE added to the pellet heated after resuspension also producedFIS but that added to the pellet resuspended in boiling waterimmediately after separation did not. A heat-stable substance(s)produced by a heat-unstable reaction in the pellet may reactwith NE to produce FIS or interact with NE to induce flowering.About 400 ng per g fresh weight of NE was detected in the waterextract of P441 plants, but only about 0.5 ng in the hot-acidicwater extract of the plants, which suggests that most of theNE was produced after homogenization. (Received October 17, 1990; Accepted December 28, 1990) 相似文献
102.
The effects of various peptides on the isolated pulmonary artery 总被引:2,自引:0,他引:2
Helical strips of pulmonary arteries from rabbits were tested for their responses to the following peptides: neuropeptide Y (NPY), vasoactive intestinal polypeptide (VIP), substance P (SP), cholecystokinin-octapeptide (CCK), somatostatin (SS), bombesin, neurotensin and gastrin. SP, in the absence of active base-tension, and NPY both induced concentration-dependent contractions, while VIP and SP, in the presence of active base-tone, and CCK induced relaxation. The pD2 (-log ED50) was in the order of NPY greater than SP and SP greater than CCK greater than VIP. SS, bombesin, NT and gastrin had no effect. These findings suggest peptidergic involvement in the vessels. 相似文献
103.
A balanced reciprocal translocation, 46,XY, t(2;12), was detected in a male infant who had the characteristic features of Sotos syndrome. His father's karyotype was normal, but his mother and an older brother had the same chromosomal abnormality without a history or clinical features of Sotos syndrome. 相似文献
104.
The effect of cell synchronization on the efficiency of stable gene transfer by electroporation 总被引:3,自引:0,他引:3
We synchronized thymidine kinase deficient mouse Ltk-cells by two different methods, hydroxyurea double-block treatment or aphidicolin single-block treatment and transformed them with the cloned herpes simplex virus thymidine kinase gene at various time intervals by the electroporation technique. Marked enhancement of stable transformation efficiency was observed at the time corresponding to the peak of G2/M phase. These results suggest that the G2/M phase is the most efficient period for stable gene transfer by electroporation. 相似文献
105.
Kwang-Deuk An Yousuke Degawa Eriko Fujihara Takashi Mikawa Moriya Ohkuma Gen Okada 《Fungal biology》2012,116(11):1134-1145
Molecular phylogenies inferred from the nuclear small subunit rRNA gene (nuSSU), nuclear large subunit rRNA gene D1/D2 region (nuLSU), and ITS-5.8S rRNA gene (ITS) indicated that five cultures of the lichenized hyphomycete Dictyocatenulata alba isolated from Japan form a monophyletic clade with high bootstrap support, and a close relationship to the Ostropomycetidae (Lecanoromycetes, Pezizomycotina, Ascomycota). Insertion sequences were found in the nuSSU of all isolates [e.g., nine insertions in the strain JCM 5358 (Japan Collection of Microorganisms)], some of which were group I introns. Five new insertion positions were found among the D. alba isolates. Using BLAST, none of the insertion sequences of D. alba were closely related to those of fungi or other organisms deposited in public DNA databases. Insertion positions were similar in some isolates, and two positions were common to all isolates. Although all phylogenetic analyses based on nuSSU, nuLSU, and ITS revealed the monophyly of D. alba, the isolates were divided into two (in the nuSSU tree) or three (in the nuLSU and ITS trees) groups. Based on the phylogenetic analyses and the intron–exon structures, the five isolates identified as D. alba belong to three cryptic species and therefore D. alba should be considered a species complex. The very slow-growing, tough agar colonies of the isolates, the occurrence of the species on both slightly lichenized and nonlichenized surfaces of trees, or pebbles (rarely on soil), suggest that the members of the D. alba complex may be lichenized. The photobiont was not clearly identified in this study. 相似文献
106.
Yoshida T Suga M Arima K Muranaka Y Tanaka T Eguchi S Lin C Yoshida S Ishikawa M Higuchi Y Seo T Ueoka Y Tomotake M Kaneda Y Darby D Maruff P Iyo M Kasai K Higuchi T Sumiyoshi T Ohmori T Takahashi K Hashimoto K 《PloS one》2011,6(5):e20469
Background
The CogState Schizophrenia Battery (CSB), a computerized cognitive battery, covers all the same cognitive domains as the Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) Consensus Cognitive Battery but is briefer to conduct. The aim of the present study was to evaluate the criterion and construct validity of the Japanese language version of the CSB (CSB-J) in Japanese patients with schizophrenia.Methodology/Principal Findings
Forty Japanese patients with schizophrenia and 40 Japanese healthy controls with matching age, gender, and premorbid intelligence quotient were enrolled. The CSB-J and the Brief Assessment of Cognition in Schizophrenia, Japanese-language version (BACS-J) were performed once. The structure of the CSB-J was also evaluated by a factor analysis. Similar to the BACS-J, the CSB-J was sensitive to cognitive impairment in Japanese patients with schizophrenia. Furthermore, there was a significant positive correlation between the CSB-J composite score and the BACS-J composite score. A factor analysis showed a three-factor model consisting of memory, speed, and social cognition factors.Conclusions/Significance
This study suggests that the CSB-J is a useful and rapid automatically administered computerized battery for assessing broad cognitive domains in Japanese patients with schizophrenia. 相似文献107.
Embryonic blood vessel formation is initially mediated through the sequential differentiation, migration, and assembly of endothelial cells (ECs). While many molecular signals that promote vascular development have been identified, little is known about suppressors of this process. In higher vertebrates, including birds and mammals, the vascular network forms throughout the embryonic disk with the exception of a region along the midline. We have previously shown that the notochord is responsible for the generation and maintenance of the avascular midline and that BMP antagonists expressed by this embryonic tissue, including Noggin and Chordin, can mimic this inhibitory role. Here we report that the notochord suppresses the generation of ECs from the mesoderm both in vivo and in vitro. We also report that the notochord diminishes the ability of mature ECs to organize into a primitive plexus. Furthermore, Noggin mimics notochord-based inhibition by preventing mesodermal EC generation and mature EC network formation. These findings suggest that the mesoderm surrounding the midline is competent to give rise to ECs and to form blood vessels, but that notochord derived-BMP antagonists suppress EC differentiation and maturation processes leading to inhibition of midline vessel formation. 相似文献
108.
M Mikawa H Kato M Okumura M Narazaki Y Kanazawa N Miwa H Shinohara 《Bioconjugate chemistry》2001,12(4):510-514
Water-soluble gadolinium (Gd) endohedral metallofullerenes have been synthesized as polyhydroxyl forms (Gd@C(82)(OH)(n)(), Gd-fullerenols) and their paramagnetic properties were evaluated by in vivo as well as in vitro for the novel magnetic resonance imaging (MRI) contrast agents for next generation. The in vitro water proton relaxivity, R(1) (the effect on 1/T(1)), of Gd-fullerenols is significantly higher (20-folds) than that of the commercial MRI contrast agent, Magnevist (gadolinium-diethylenetriaminepentaacetic acid, Gd-DTPA) at 1.0 T close to the common field of clinical MRI. This unusually high proton relaxivity of Gd-fullerenols leads to the highest signal enhancement at extremely lower Gd concentration in MRI studies. The strong signal was confirmed in vivo MRI at lung, liver, spleen, and kidney of CDF1 mice after i.v. administration of Gd-fullerenols at a dose of 5 micromol Gd/kg, which was 1/20 of the typical clinical dose (100 micromol Gd/kg) of Gd-DTPA. 相似文献
109.
T Kanahara M Hirokawa M Shimizu K Terayama E Nakamura Y Hino Y Mikawa T Manabe 《Acta cytologica》1999,43(3):425-428
BACKGROUND: Solitary fibrous tumor is a rare spindle cell tumor and has been forced at a variety of sites. To the best of our knowledge, only two cases of solitary fibrous tumor arising in the spinal cord have been reported; no cytologic findings were documented. CASE: A 62-year-old male presented with a spinal cord tumor. A scrape smear of the resected tumor revealed naked, spindle-shaped nuclei. Some nuclei were twisted or had long spindles. In the background, abundant, thin and thick collagen fibers were present. Immunohistochemically, the spindle cells were positive for CD34 and negative for S-100 protein and alpha-smooth muscle actin. Histologic diagnosis of the tumor was benign solitary fibrous tumor. CONCLUSION: Our case indicates that solitary fibrous tumor can occur in the spinal cord and should be differentiated from other benign spindle cell tumors, such as meningioma and schwannoma. The key cytologic features of solitary fibrous tumor may be the presence of abundant thin and thick collagen fibers in scrape specimens. 相似文献
110.
Kunihiro Azuma Tomoko Koumura Ryo Iwamoto Masaki Matsuoka Ryo Terauchi Shu Yasuda Tomoyasu Shiraya Sumiko Watanabe Makoto Aihara Hirotaka Imai Takashi Ueta 《The Journal of biological chemistry》2022,298(4)
Glutathione peroxidase 4 (GPx4) is known for its unique function in the direct detoxification of lipid peroxides in the cell membrane and as a key regulator of ferroptosis, a form of lipid peroxidation–induced nonapoptotic cell death. However, the cytosolic isoform of GPx4 is considered to play a major role in inhibiting ferroptosis in somatic cells, whereas the roles of the mitochondrial isoform of GPx4 (mGPx4) in cell survival are not yet clear. In the present study, we found that mGPx4 KO mice exhibit a cone–rod dystrophy-like phenotype in which loss of cone photoreceptors precedes loss of rod photoreceptors. Specifically, in mGPx4 KO mice, cone photoreceptors disappeared prior to their maturation, whereas rod photoreceptors persisted through maturation but gradually degenerated afterward. Mechanistically, we demonstrated that vitamin E supplementation significantly ameliorated photoreceptor loss in these mice. Furthermore, LC–MS showed a significant increase in peroxidized phosphatidylethanolamine esterified with docosahexaenoic acid in the retina of mGPx4 KO mice. We also observed shrunken and uniformly condensed nuclei as well as caspase-3 activation in mGPx4 KO photoreceptors, suggesting that apoptosis was prevalent. Taken together, our findings indicate that mGPx4 is essential for the maturation of cone photoreceptors but not for the maturation of rod photoreceptors, although it is still critical for the survival of rod photoreceptors after maturation. In conclusion, we reveal novel functions of mGPx4 in supporting development and survival of photoreceptors in vivo. 相似文献