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1.
A spectrophotometric method for inorganic phosphate determination in the presence of thiol compounds is described. Thiol compounds, which interfere with the measurement of inorganic phosphate by a modification of the method of Gomori, are removed by carboxymethylation by iodoacetate prior to the formation and reduction of phosphomolybdate complex. A linear standard curve is obtained by this method, and the method is suitable for the assay of a phosphate-releasing enzyme when the measurement must be performed in the presence of thiol compounds. 相似文献
2.
A radioimmunoassay for human pro-luteinizing hormone-releasing factor [pro-LRF(14-69)OH] 总被引:1,自引:0,他引:1
A Motoyama I Wakabayashi S Minami H Sugihara F Takahashi S Akira N Ling 《Endocrinologia japonica》1987,34(1):133-137
A radioimmunoassay (RIA) for human pro-LRF(14-69)OH was developed with an antiserum, generated in a rabbit, to [Tyr67]pro-LRF(47-67)NH2 conjugated to BSA. This antiserum bound 28-32% of [125I]pro-LRF(14-69)OH at a final dilution of 1:2500 and the binding was inhibited by pro-LRF(14-69)OH in a dose-dependent manner. The sensitivity of the RIA was 31.2-62.5 pg and the dose that inhibited 50% of the binding to the tracer was 280-320 pg. Intra- and inter-assay coefficients of variation at 50% inhibition were 8 and 12%, respectively. Neither LRF nor pro-LRF(14-37)OH was recognized by the antiserum. The dilution curve generated with human hypothalamic extract was parallel to that of pro-LRF(14-69)OH. In addition the extract yielded a major immunoreactive peak emerging in elution volumes concordant with [125I]pro-LRF(14-69)OH on Sephadex G-50 chromatography. 相似文献
3.
Interleukin-4 downregulates interleukin-6 production by human alveolar macrophages at protein and mRNA levels. 总被引:2,自引:0,他引:2
Effects of interleukin-4 (IL-4) on IL-6 production by human alveolar macrophages (AM) obtained by bronchoalveolar lavage from healthy donors was examined at the protein and gene levels. IL-6 production was quantitated by enzyme immunoassay (EIA) and bioassay using the IL-6 dependent murine hybridoma cell line MH60.BSF2. Results showed that when activated with LPS, AM released significantly more biologically active IL-6 than blood monocytes. Human rIL-4 significantly suppressed IL-6 production by AM and monocytes stimulated with LPS. Northern blot analysis revealed that IL-4 reduced the expression of IL-6 mRNA in LPS-stimulated AM and monocytes. The inhibitory effect was most pronounced when IL-4 was added with LPS or within the first 4 hr after LPS to AM or monocytes. The suppressive effect of IL-4 was completely neutralized by pretreatment with anti-IL-4 antibody. IL-4 also showed a suppressive effect on IL-6 production by macrophages generated in vitro by maturation of blood monocytes with granulocyte-macrophage colony stimulating factor (GM-CSF). These observations suggest that IL-4 may play a critical role in in situ regulation of immune responses through suppression of IL-6 production. 相似文献
4.
Microorganisms of the San Francisco Sour Dough Bread Process: I. Yeasts Responsible for the Leavening Action 总被引:6,自引:5,他引:1 下载免费PDF全文
Two hundred isolates from San Francisco sour dough French bread fermentations (40 from each of five different bakeries) were screened by fermentation tests and for their ability to grow in the presence of cycloheximide (Actidione). All of the isolates from four of the bakeries and 70% of those from the fifth were unable to utilize maltose but grew well on other sugars, even in the presence of cycloheximide. The remaining few isolates from the fifth bakery utilized maltose but not galactose and were inhibited by cycloheximide. No bakers' yeast types were found. Sixteen of the maltose-negative and five of the galactose-negative isolates were subjected to more rigorous taxonomic procedures. All of the maltose-negative isolates were identified as asporogenous strains of Saccharomyces exiguus (Torulopsis holmii) and the galactose-negative ones, as S. inusitatus. The predominance of S. exiguus, its vigor in the particular acidic environment of the sour dough, and the correlation of its numbers with the leavening function constitute strong evidence on the role of this organism in the sour dough system. 相似文献
5.
Establishment of five human myeloma cell lines 总被引:3,自引:0,他引:3
Masayoshi Namba Takemi Ohtsuki Masaharu Mori Atsushi Togawa Hideho Wada Takashi Sugihara Yoshihito Yawata Tetsuo Kimoto 《In vitro cellular & developmental biology. Plant》1989,25(8):723-729
Summary Five human myeloma cell lines, KMM-1, KMS-5, KMS-11, KMS-12- PE, and KMS-12-BM, have been established at Kawasaki Medical
School since 1980. As the KMS-12-PE and KMS-12-BM lines were obtained from the same patient, these five cell lines have been
derived from four patients with multiple myeloma. The five myeloma cell lines are stably growing at present in RPMI 1640 medium
supplemented with 10% fetal bovine serum. They can also grow in a defined culture medium without serum. That these cell lines
were, human myeloma cells was confirmed by the following findings. Ultranstructually, all five cell lines showed features
characteristic of plasma cells. KMM-1 and KMS-11 cells secreted lambda and kappa chains into the culture medium, respectively,
but the other cell lines produced no immunoglobulins. KMM-1 expressed cytoplasmic lambda antigen, KMS-5 showed cytoplasmic
delta, and KMS-11 expressed surface kappa, whereas KMS-12-PE and KMS-12-BM cells showed no surface or cytoplasmic immunoglobulins.
Regarding reaction with a monoclonal plasma cell antibody (PCA-1), four of the five lines were positive, the exception being
KMS-5. Another monoclonal antibody (CD38), which also recognizes plasma cells, reponded to KMM-1, KMS-12-PE, and KSM-12-BM.
KMS-5 cells expressed acute lymphoblastic leukemia antigens (CALLA). These data suggest that such lines as KMM-1, KMS-11,
KMS-12-PE, and KMS-12-BM represent later stages of B-cell differentiation, and that KMS-5 represents a relatively early stage
of B-cell differentiation. All the cell lines lacked Epstein-Barr virus nuclear antigen, showed abnormal karyotypes of human
origin, and differed from each other in the isozyme patterns examined. Only KMS-5 was tumorigenic when transplanted subcutaneously
into nude mice. 相似文献
6.
7.
Structures and properties of seven isoforms of the NMDA receptor generated by alternative splicing. 总被引:19,自引:0,他引:19
H Sugihara K Moriyoshi T Ishii M Masu S Nakanishi 《Biochemical and biophysical research communications》1992,185(3):826-832
We here report the existence of 6 additional isoforms of the NMDA receptor generated via alternative splicing by molecular analysis of cDNA clones isolated from a rat forebrain cDNA library. These isoforms possess the structures with an insertion at the extracellular amino-terminal region or deletions at two different extracellular carboxyl-terminal regions, or those formed by combinations of the above insertion and deletions. One of the deletions results in the generation of a new carboxyl-terminal sequence. All these isoforms possess the ability to induce electrophysiological responses to NMDA and respond to various antagonists selective to the NMDA receptor in the Xenopus oocyte expression system. In addition, a truncated form of the NMDA receptor also exists that contains only the extreme amino-terminal sequence of this protein molecule. These data indicate that the NMDA receptor consists of heterogeneous molecules that differ in the extracellular sequence of the amino- and carboxyl-terminal regions. 相似文献
8.
In the present study, anti-metastatic effect of Z-100 on the spontaneous pulmonary metastases of Lewis lung carcinoma (3LL)
was examined in an attempt to regulate suppressor T cells. When Z-100 (10 mg/kg) was daily injected i.p. after 3LL inoculation,
survival rate of these mice was increased significantly (p<0.05). In addition, the number of pulmonary metastatic colonies of 3LL in Z-100-treated mice were significantly decreased
by 38% at 21 days, as compared with that of control mice (p<0.05). Along with the decrease of pulmonary metastases, suppressor cell activity was also gradually reduced in these mice,
as compared with that of control mice. When splenic suppressor cells (5×107 cells) from 3LL-bearing mice were adoptively transferred into normal mice (recipients) just before inoculation of 3LL, the
development of pulmonary metastases in recipients was significantly accelerated. However, splenocytes from 3LL-bearing mice
treated with Z-100 did not affect the development of pulmonary metastasis. The potential to accelerate the metastasis of splenic
mononuclear cells from 3LL-bearing mice was decreased significantly by the treatment with anti-Thy 1.2 monoclonal antibody
(mAb), anti-Lyt 2.2 mAb or anti-CD11b mAb followed by complement. IL-4 activity in the sera of 3LL-bearing mice was detected
15 days after tumor inoculation (13 pg/ml) and gradually increased (18 pg/ml) 20 days after tumor inoculation. However, when
Z-100 (10 mg/kg) was daily injected i.p., IL-4 activity in sera was decreased significantly, and the IL-4 activity was not
detected in these mice on day 20. These results suggest that Z-100 could inhibit the pulmonary metastases in 3LL-bearing mice
through the inhibition of suppressor T cell activity and a possible candidate of its effector molecule, IL-4. 相似文献
9.
Lucas P. Medeiros Stefano Allesina Vasilis Dakos George Sugihara Serguei Saavedra 《Ecology letters》2023,26(1):170-183
Managing ecological communities requires fast detection of species that are sensitive to perturbations. Yet, the focus on recovery to equilibrium has prevented us from assessing species responses to perturbations when abundances fluctuate over time. Here, we introduce two data-driven approaches (expected sensitivity and eigenvector rankings) based on the time-varying Jacobian matrix to rank species over time according to their sensitivity to perturbations on abundances. Using several population dynamics models, we demonstrate that we can infer these rankings from time-series data to predict the order of species sensitivities. We find that the most sensitive species are not always the ones with the most rapidly changing or lowest abundance, which are typical criteria used to monitor populations. Finally, using two empirical time series, we show that sensitive species tend to be harder to forecast. Our results suggest that incorporating information on species interactions can improve how we manage communities out of equilibrium. 相似文献
10.
Two soluble glycoproteins containing hydroxyproline were extractedfrom cultured tobacco cells (cell line XD-6S) and purified byion-exchange and gel-filtration chromatography. On DEAR-cellulosecolumn chromatography in the final step of the purification,one was eluted at 90 mM NaCl and the other at 120 mM as singlepeak. Both purified glycoproteins were also sedimented as singlepeak with an ultracentrifugation. The S20,w values were 6.1for the former and 7.0 for the latter. These glycoproteins were composed of 94% polysaccharide and6% protein in the former, and 87% polysaccharide and 13% proteinin the latter. The sugar moiety consisted of galactose, arabinose,rhamnose, and uronic acid in both. Hydroxyproline accountedfor 12% in the former and 20% in the latter amino acid composition.A high content of alanine in both (14 and 15%) was one of thedistinctive characteristics of these soluble glycoproteins. These intracellular soluble hydroxyproline-containing glycoproteinswere not labelled within 30 min of incubation with 3H-proline,although the radioactivity was rapidly incorporated (within15 min) into the intracellular macromolecules. (Received February 21, 1978; ) 相似文献