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21.
Interleukin 1-like factors can accumulate 5-hydroxytryptamine in the liver of mice and can induce hypoglycaemia 总被引:3,自引:0,他引:3
After the injection into mice of culture medium of P388D1 cells, a murine macrophage cell line, 5-hydroxytryptamine accumulated in the liver and blood glucose declined. The factors capable of inducing these responses were purified by gel filtration and chromatofocusing. With these procedures, the activity to induce the increase in 5-hydroxytryptamine in the liver accompanied the activity to induce hypoglycaemia. Moreover, through the purification, the factors were found in the fraction of interleukin 1, a lymphocyte-activating factor. These results suggest that the factors capable of inducing the increase in 5-hydroxytryptamine and hypoglycaemia are likely to be interleukin 1 molecules or molecules closely related to interleukin 1. The present and previous findings together with those in the literature support the idea that the increase in 5-hydroxytryptamine in the liver might be a cause of hypoglycaemia. These findings may provide new and important information about the roles of macrophages in inflammation or in immune responses. 相似文献
22.
Protease induced by ultraviolet rays (UV) has been extensively investigated in human cells. Plasminogen activator-like protease (PA) activity was induced soon after UV irradiation in peripheral lymphocytes derived from healthy donors. In contrast, UV-irradiated lymphocytes derived from Cockayne syndrome (CS) cases did not show marked protease inducibility. Epstein-Barr (EB) virus-transformed CS lymphoblastoid cells were also characterized by insusceptibility to UV-induction of PA. However, when CS-derived cells were treated with a human interferon (HuIFN) preparation prior to irradiation, induction of PA activity was detected, irrespective of the kind of HuIFN (alpha or gamma). The results indicate the possibility of abnormal PA metabolism in CS-derived cells. 相似文献
23.
-Octopamine was characterized as substrate for monoamine oxidase (MAO) in rat brain and liver mitochondria. The m and max values of the brain enzyme were 735 μM and 32.5 nmoles/mg protein/30 min, and those of the liver enzyme 351 μM and 125 nmoles/mg protein/30 min, respectively. The inhibition experiments with clorgyline and deprenyl showed that -octopamine was a common substrate for type A and type B MAO, though a major part of the activity was due to type A enzyme. 相似文献
24.
S Hoshino M Suzuki T Kakegawa K Imai M Wakita Y Kobayashi Y Yamada 《Comparative biochemistry and physiology. A, Comparative physiology》1988,90(2):355-359
1. Circulating concentrations of iodothyronines, luteinizing hormone(LH), estradiol(E2), progesterone and corticosterone were measured in hens before, during, and after a forced molt induced by fasting. 2. Corticosterone increased at the onset of molt, peaked at the maximal molt and returned to pre- and post-molt levels. LH, E2 and progesterone declined during the molt, and the decline was coincident with the cessation of egg production. 3. Thyroxine(T4), triiodothyronine (T3) and reverse triiodothyronine(rT3) increased during the molt. The increases of T4 and T3 were not abolished even if the forced molt was conducted in mild weather. 相似文献
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27.
Knowledge on transport and deposition of fine particulate organic matter (FPOM) from reservoir dams is increasingly required
for habitat management and restoration of dam tailwater ecosystems. Variations in the transport distance of FPOM, however,
have never been studied well, particularly in relation to channel morphology, due to channel size restrictions of artificial
tracers such as corn pollen when applied to larger river channels. This study aims to show the relations between FPOM retention
efficiency and channel morphology in dam tailwaters using lentic plankters as tracers. We estimated the mean transport distance,
S
p, by calculating downstream reduction ratios of lentic tracer plankters and calculated the deposition velocity, v
dep. Suspended FPOM samples were collected in tailwaters of two river channels below reservoir dams and two artificial canals
below Lake Biwa in the Yodo River system. The longest S
p (19.2 km) and the shortest one (2.2 km) were recorded in the deep canal and shallow canal, respectively, showing a positive
correlation with channel hydraulic radius. The values of v
dep were 4.7–6.4 times higher in river channels than in artificial canals. These results indicate that increasing complexity
of bed morphology can minimize S
p, whereas bed degradation and armored bed materials may lead to increased S
p. Advantages of lentic plankters as tracers for estimating distance ranges of reservoir dam impact on river ecosystems are
also discussed. 相似文献
28.
Viable cells of Saccharomyces cerevisiae 4484-24D-1 mutant strain were treated with an Arthrobacter sp. beta-1,3-glucanase, Zymolyase-60,000, in the presence of a serine protease inhibitor, phenylmethylsulfonyl fluoride. Fractionation of the solubilized materials with Cetavlon (cetyltrimethylammonium bromide) yielded a purified mannan-protein complex, which had a molecular weight of ca. 150,000, approximately three times higher than that of the mannan isolated from the same cells by the hot-water extraction method at 135 C. The amino acid composition of the mannan-protein complex was found to be very similar to that of the mannan-protein complexes of S. cerevisiae X2180-1A wild and S. cerevisiae X2180-1A-5 mutant strains, indicating the presence of large amounts of serine and threonine. It was unexpected that the antibody-precipitating activity of this complex against the homologous anti-whole cell serum was about twice as great as that of the mannan isolated by hot-water extraction. Treatment of this complex with 100 mM NaOH, hot water at 135 C, and pronase, respectively, gave degradation products having the same molecular weight and antibody-precipitating activity as those of the hot-water extracted mannan, allowing the assumption that the protein moiety participated in a large part of this activity. 相似文献
29.
T Ogawa M Hyodo S Ihara M Takekoshi K Minato K Suzuki 《Cell structure and function》1987,12(6):567-574
High-frequency transfection of mouse FM3A cells, grown in suspension, with plasmid pSV2neo DNA was achieved by incubation of the cells with DNA plus polybrene for 6 h followed by an osmotic shock with a hypertonic NaCl solution. When incubated for 20 min at 34 degrees C, FM3A cells showed resistance to the osmolarity change from 0.1 to 9.0% NaCl in the medium. Within this concentration range, 5-7% gave the highest efficiency of transfection. Both linear and circular forms of plasmid DNA produced transformants with equal efficiency. This method was simple, reproducible, and carrier DNA was not required. The efficiency was about 100 times higher than that of the method with DNA-calcium phosphate precipitates. Transformed cells were stable and different numbers of plasmid DNA copies were detected. 相似文献
30.