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71.
Cartilage-derived factor (CDF) : II. Somatomedin-like action on cultured chondrocytes 总被引:2,自引:0,他引:2
Yukio Kato Yoshio Nomura Mitsuko Tsuji Hiroaki Ohmae Masahiko Kinoshita Shinji Hamamoto Fujio Suzuki 《Experimental cell research》1981,132(2):339-347
Previously, we showed that fetal bovine cartilage contains a polypeptide that stimulates the incorporation of [35S]sulfate into proteoglycans synthesized by rat and rabbit costal chondrocytes in culture. In this paper, we report that the cartilage-derived factor (CDF) increases not only [35S]sulfate incorporation but also [3H]thymidine incorporation into rabbit chondrocytes in monolayer culture. The dose-response curve of CDF stimulation of DNA synthesis was similar in profile to that of CDF stimulation of proteoglycan synthesis. In addition, CDF markedly enhanced [3H]uridine incorporation into rabbit chondrocytes and significantly enhanced [3H]serine incorporation into total protein. These findings indicate that fetal bovine cartilage contains a factor that shows somatomedin-like activity in monolayer cultures of rabbit chondrocytes. 相似文献
72.
Yuji Inada Yukio Tazawa Attula Attygalle Yuji Saito 《Biochemical and biophysical research communications》1980,96(4):1586-1591
Four enzymes in urea cycle and inorganic pyrophosphatase were immobilized simultaneously into a matrix of fibrin fiber formed from fibrinogen by the concerted action of thrombin and blood coagulation Factor XIII. The immobilized multienzyme system not only had an ability to carry out urea cycle continuously at least over several hours, but also had a greatly improved efficiency over the corresponding soluble system. 相似文献
73.
In in vitro tests, amines were screened for the inhibition of polar filament extrusion by spores ofPlistophora anguillarum, a microsporidian parasite of the eel. Primary amines having C8
− C18 alkyl chains were effective, irrespective of the anions bound. Secondary amines having a branched C8 chain and tertiary amines having C14−C18 chains were also effective. Asymmetry in side chains seemed to be required for inhibitory action. Quaternary ammonium salts
having C12−C16 alkyl chains and some germicides or disinfectants such as cetyl pyridinium chloride and benzethonium chloride were also effective.
Diamines and amides were ineffective regardless of the length of their alkyl chins. In in vivo tests, eel larvae-fed for 4
days with a commercial feed supplemented with 5×108 cells of spores and 4g of laurylamine aspartate/100 g feed, and thereafter with the usual commercial feed for 26 days—were
not infected. 相似文献
74.
Minoru Okuma Yukio Yamori Kiyoe Ohta Haruto Uchino 《Prostaglandins & other lipid mediators》1979,17(1):1-7
Activities of aortae to produce prostaglandin (PG) I2-like substance in stroke-prone spontaneously hypertensive rats (SHRSP), stroke-resistant SHR (SHRSR) and normotensive control rats from the Wistar-Kyoto (WK) colony were compared. PGI2-like substance was produced by the incubation of the aortic ring in pH 9.0 borate-buffered saline and the amount produced was estimated by comparison of its anti-aggregatory activity with that produced by known amounts of the sodium salt of synthetic PGI2. Before the development of stroke, amounts of this substance generated in SHRSP and SHRSR were significantly higher than those in WK rats (p<0.01 and p<0.02, respectively). Remarkably reduced capacity to generate PGI2-like substance was observed in some SHRSP after the development of stroke. 相似文献
75.
Enzymes of purine catabolism in soybean plants 总被引:2,自引:0,他引:2
Remarkable formation and utilization of allantoin is observedin soybean (Glycine max variety A62-1). To study this, variousenzymes involved in purine catabolism (i.e., xanthine oxidase,uricase and allantoinase) were measured in different regionsof soybean plants during development. Uricase, which catalyzesthe direct formation of allantoin from uric acid, was studiedin detail. The activities of these three enzymes were highest in the rootnodules, indicating that the nodules are the major site of allantoinmetabolism. Radicles only showed appreciable activity about80 hr after the seeds were planted. Allantoinase activity wasdetected in all regions tested, showing that allantoin translocatedfrom the nodules can be metabolized in the roots, stem and leaves.In the nodules, xanthine oxidase was localized in the nuclearfraction, while uricase was mainly restricted to the mitochondrialfraction and allantoinase to the soluble fraction. Uricase was partially purified from the nodules and radicles,respectively. The pH optimum of enzyme from the nodules was9.5, whereas that of enzyme from the radicles was 7.0. The enzymefrom the nodules did not require a cofactor, while that fromthe radicles showed an absolute requirement for a cofactor,which was a low molecular substance easily separable from theapoprotein. Thus, the uricase in nodules differs in chemicalproperties from that in the host plant. The results are discussedin relation to change in the allantoin level in soybean tissues. (Received November 1, 1974; ) 相似文献
76.
This study describes the ultrastructural characteristics of the middle cerebral artery and its related neural elements in the squirrel monkey and baboon. The cytoarchitecture of the M-1 segment as well as that of the smaller extracerebral and intracerebral vessels is comparable in both animals.Smooth muscle elements are occasionally found within the intimai lining. The nerve bundles associated with vessels contain fewer myelinated fibers as the vessel diameter decreases. The cytological relationship between the neural structures and the smooth muscle cells are discussed. 相似文献
77.
From the root bark of Hovenia dulcis Thunb. and H. tommentella (Makino) Nakai (Rhamnaceae), three peptide alkaloids, frangulanine, hovenins-A and -B have been isolated. Hovenin-A has been shown to be des-N-methylfrangulanine (II). 相似文献
78.
Takayuki Murata Satoshi Komoto Satoko Iwahori Jun Sasaki Hironori Nishitsuji Terumitsu Hasebe Kiyotaka Hoshinaga Yukio Yuzawa 《Microbiology and immunology》2021,65(1):10-16
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is causing the global coronavirus disease 2019 (COVID-19) pandemic. Because complete elimination of SARS-CoV-2 appears difficult, decreasing the risk of transmission is important. Treatment with 0.1 and 0.05 ppm ozone gas for 10 and 20 hr, respectively, decreased SARS-CoV-2 infectivity by about 95%. The magnitude of the effect was dependent on humidity. Treatment with 1 and 2 mg/L ozone water for 10 s reduced SARS-CoV-2 infectivity by about 2 and 3 logs, respectively. Our results suggest that low-dose ozone, in the form of gas and water, is effective against SARS-CoV-2. 相似文献
79.
Taiki Hanzawa Kyohei Shibasaki Takahiro Numata Yukio Kawamura Thierry Gaude Abidur Rahman 《The Plant cell》2013,25(9):3424-3433
High-temperature-mediated adaptation in plant architecture is linked to the increased synthesis of the phytohormone auxin, which alters cellular auxin homeostasis. The auxin gradient, modulated by cellular auxin homeostasis, plays an important role in regulating the developmental fate of plant organs. Although the signaling mechanism that integrates auxin and high temperature is relatively well understood, the cellular auxin homeostasis mechanism under high temperature is largely unknown. Using the Arabidopsis thaliana root as a model, we demonstrate that under high temperature, roots counterbalance the elevated level of intracellular auxin by promoting shootward auxin efflux in a PIN-FORMED2 (PIN2)-dependent manner. Further analyses revealed that high temperature selectively promotes the retrieval of PIN2 from late endosomes and sorts them to the plasma membrane through an endosomal trafficking pathway dependent on SORTING NEXIN1. Our results demonstrate that recycling endosomal pathway plays an important role in facilitating plants adaptation to increased temperature. 相似文献
80.
Yukio Kitade Masaharu Wakana Shin-ichi Terai Takayuki Tsuboi Masayuki Nakanishi Chizuko Yatome 《Nucleosides, nucleotides & nucleic acids》2013,32(12):2323-2333
Abstract 2-Bromoadenosine-substituted analogues of 2–5A, p5′A2′p-5′A2′p5′(br2A), p5′(br2A)2′p5′A2′p5′A, and p5′(br2A)2′p5′(br2A)2′p-S′(br2A), were prepared via a modification of a lead ion-catalyzed ligation reaction and were subsequently converted into the corresponding 5′-triphosphates. Both binding and activation of human recombinant RNase L by various 2-bromoadenosine-substituted 2–5A analogues were examined. Among the 2-bromoadenosine-substituted 2–5A analogues, the analogue with 2-bromoadenosine residing in the 2′-terminal position, p5′A2′p5′A2′p-5′(br2A), showed the strongest binding affinity and was as effective as 2–5A itself as an activator of RNase L. The CD spectrum of p5′A2′p-5′A2′p5′(br2A) was superimposable on that of p5′A2′p5′A2′p5′A, indicative of an anti orientation about the base-glycoside bonds as in naturally occurring 2–5A. 相似文献