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141.
Recombinant human interleukin 1 (rhIL-1)alpha and rhIL-1 beta were examined for their effects on DNA synthesis, cell growth and alkaline phosphatase activity of the mouse osteoblastic cell line MC3T3-E1. The relative activity of rhIL-1 alpha and rhIL-1 beta was compared in terms of the units which induced half-maximal [3H]thymidine uptake into mouse thymocyte cultures exposed to IL-1. Both rhIL-1 alpha and rhIL-1 beta significantly inhibited DNA synthesis and division of the cells in a concentration- and cultivation time-dependent fashion. In contrast, rhIL-1 alpha and rhIL-1 beta markedly increased alkaline phosphatase activity, which is a marker of osteoblastic differentiation. This activity in cells treated with rhIL-1 alpha and rhIL-1 beta increased about 2.0- and 1.7-fold, respectively, compared with that of control cultures. Inhibition of the DNA synthesis and stimulation of alkaline phosphatase activity by both types of rhIL-1 were completely neutralized by treatment with their respective polyclonal antisera. Also, inhibition of DNA synthesis was unaffected by the addition of cyclooxygenase and lipoxygenase inhibitors, and stimulation of alkaline phosphatase activity was unaffected by the addition of indomethacin. These results indicate that both rhIL-1 alpha and rhIL-1 beta have qualitatively similar biological effects on osteoblastic cells. They also suggest that IL-1 is an important modulator of the growth and differentiation of osteoblasts.  相似文献   
142.
A [2Fe-2S] ferredoxin was found in Pseudomonas ovalis which was grown in a medium supplemented with glucose and ammonium sulfate. The molecular weight of the 2Fe ferredoxin was estimated to be 13,000. It contained 2.2 gramatoms of non-heme iron and 2.3 gramatoms of acid-labile sulfur per mole protein. The absorption and circular dichroism spectra were characteristic of those of [2Fe-2S] type ferredoxins, especially adrenodoxin and putidaredoxin. The electron paramagnetic resonance spectrum of the reduced protein showed an axial symmetry (g = 2.020, g = 1.939). The amino acid composition was determined.  相似文献   
143.
Carbon metabolism in photosynthesizing and respiring cells of Botryococcus braunii was radically changed by the presence of 1 mM NH4Cl in the medium, when the so-called resting state previously had been subjected to a nitrogen-deficient medium. Ammonia addition to the algae photosynthesizing with 14C-labelled HCO 3 - almost completely inhibited the synthesis of 14C-labelled botryococcenes and other hexane-extractable compounds, and also inhibited the formation of insoluble compounds; however, it resulted in a large increase in the synthesis of alanine, glutamine, other amino acids, and especially of 5-aminolevulinic acid. Total CO2 fixation decreased about 60% and O2 evolution decreased more than 50%.CO2 fixation in the dark with ammonia present led to labelled products derived from phosphoenolpyruvate carboxylation, such as glutamine, glutamate, and malate. Respiratory uptake of O2 increased by about 70%.The inhibition of terpenoid synthesis and increased synthesis of C5 amino acids by Botryococcus upon ammonia addition indicates 1) a diversion of acetyl coenzyme A from synthetic pathways leading to terpenoids and 2) increased operation of pathways leading to the synthesis of amino acids, especially 5-aminolevulinic acid, a precursor to chlorophyll biosynthesis.This work was supported in part by the Office of Energy Research, Office of Basic Energy Sciences, Biological Energy Research Division of the U.S. Department of Energy under Contract No. DE-AC03-76SF00098, in part by a grant from SOHIO, and, in part, by a grant from the Japan-U.S. Cooperative Science Program (The Japan Society for the Promotion of Science, National Science Foundation, Division of International Programs)  相似文献   
144.
A case of malignant Müllerian mixed tumor of the uterus, exhibiting a histology of heterologous osteosarcomatous differentiation, is presented. Special emphasis is placed on the characteristic immunohistochemical reactivity of the tumor tissue in comparison with that of normal uterine tissue in the proliferative phase. Keratin, cytokeratin, epithelial membrane antigen (EMA), carcinoembryonic antigen (CEA), and human chorionic gonadotropin (HCG) were found only in the carcinomatous element. However, neuron specific enolase (NSE), S-100 protein (S 100) and vimentin were identified in almost all tumor tissue elements. Desmin and actin were not stained in any elements. Myoglobin was only detected weakly in the squamous carcinomatous element. Undifferentiated cell element, composed of small, round, spindle, or polygonal cells showed positive reactions to NSE and S 100, but not to any other antibodies. As compared to the reactivities of the normal proliferative endometrium, the glandular epithelial cells were positive with NSE, S 100, vimentin and CEA, but the stromal cells were only positive with vimentin. Such a multitudinous and concomitant expression of antigenicity to the different tumor elements indicates a close relationship to its mesodermal Müllerian origin, and NSE, S 100 and vimentin might be most adequate indicators of these types of tumors.  相似文献   
145.
We have produced rabbit antibodies against synthetic peptides corresponding to the mid-region (amino acid residues 172-202, C peptide) and to the unique segment near the transmembrane region (amino acid residues 341-370, P peptide) in the extracellular component of the human thyrotropin (TSH) receptor and evaluated their biological activities. Both anti-C peptide antibodies raised in two rabbits showed strong thyroid stimulating activities (TSAb) (4127% and 2548%). Anti-P peptide antibodies raised in two rabbits were also strongly positive for TSAb activities (359% and 3468%). However, none of these antibodies had TSH-binding inhibitor immunoglobulin (TBII) activities. These results suggest that the domains responsible for TSAb are likely to span the entire extracellular component of the TSH receptor.  相似文献   
146.
A 260-kDa structural cell wall protein was purified from sodium dodecyl sulfate-treated cell walls of Saccharomyces cerevisiae by incubation with Rarobacter faecitabidus protease I, which is a yeast-lytic enzyme. Amino acid sequence analysis revealed that this protein is the product of the SED1 gene. SED1 was formerly identified as a multicopy suppressor of erd2, which encodes a protein involved in retrieval of luminal endoplasmic reticulum proteins from the secretory pathway. Sed1p is very rich in threonine and serine and, like other structural cell wall proteins, contains a putative signal sequence for the addition of a glycosylphosphatidylinositol anchor. However, the fact that Sed1p, unlike other cell wall proteins, has six cysteines and seven putative N-glycosylation sites suggests that Sed1p belongs to a new family of cell wall proteins. Epitope-tagged Sed1p was detected in a β-1,3-glucanase extract of cell walls by immunoblot analysis, suggesting that Sed1p is a glucanase-extractable cell wall protein. The expression of Sed1p mRNA increased in the stationary phase and was accompanied by an increase in the Sed1p content of cell walls. Disruption of SED1 had no effect on exponentially growing cells but made stationary-phase cells sensitive to Zymolyase. These results indicate that Sed1p is a major structural cell wall protein in stationary-phase cells and is required for lytic enzyme resistance.  相似文献   
147.
Non-thyroid mammalian cells, CHO-K1 cells, stably expressing human thyrotropin receptor (CHO-TSH-R cells) were used for the assay of thyroid stimulating antibody (TSAb) activities of IgGs from 24 patients with Graves' disease and we compared them with the values obtained in porcine thyroid cells. A significant positive correlation was observed between the results given by CHO-TSH-R cells (hTSAb) and porcine thyrocytes (pTSAb) (r = 0.94, p less than 0.001). However, we found that hTSAb values of IgGs from 5 patients were extremely different from their hTSAb values. Four out of these 5 IgGs showed strong pTSAb activity but exhibited a weak or negative hTSAb activity. Conversely, one out of 5 autoantibodies was very strong for hTSAb but its pTSAb was low. These heterogeneous responses of recombinant hTSH-R to Graves' IgGs suggest that there exist different types of TSAb and also that the epitope(s) for TSAb may be different from case to case.  相似文献   
148.
A papain-catalyzed reaction involving the covalent attachment of L-leucine ra-dodecyl ester [Agric. Biol. Chem., 44, 1979 (1980)] was applied to gelatin and succinylated fish protein concentrate. Proteinaceous surfactants formed were found suitable for emulsification of soybean oil. The emulsions prepared with these surfactants were characterized by having a variety of functional properties in terms of hardness, adhesiveness, viscosity and viscoelasticity. Any particular property could be reproduced by intentionally setting the proper conditions for emulsification; for example, the use of a high surfactant concentration resulted in gel formation. The functions of the proteinaceous surfactants were different in many respects from those of Tween-60 and a type of sucrose fatty acid ester used as controls. Several data were added explaining such differences. The feasibility of preparing a mayonnaise-like concentrated emulsion by use of the proteinaceous surfactants is discussed.  相似文献   
149.
Imidafenacin (KRP-197/ONO-8025, IM), 4-(2-methyl-1H-imidazol-1-yl)-2,2-diphenylbutanamide, is a new antimuscarinic agent currently under application for the indication of treatment of overactive bladder in Japan. We developed and validated the sensitive and selective bioanalytical methods for the extremely low levels of IM and its metabolite, M-2 (Method 1), M-4 (Method 2) and M-9 (Method 3) in human plasma using liquid chromatography-tandem mass spectrometry (LC-MS/MS). In each method, plasma sample was extracted by solid phase extraction, separated on a semi-micro high performance liquid chromatography column and detected by tandem mass spectrometer with an atmospheric pressure chemical ionization or ionspray interface. Selected reaction monitoring mode was used for quantification. Each method was found to have acceptable accuracy, precision, stability, selectivity and linearity over the concentration range of 10-500 pg/mL for IM and M-2, 10-1000 pg/mL for M-4 and 50-5000 pg/mL for M-9. Using these analytical methods, concentration profiles of IM and its metabolites in human plasma were successfully determined even in the low pg/mL levels after oral administration of IM at the therapeutic dosage of 0.1 mg.  相似文献   
150.
The changes in the expression of sigma factor genes during dehydration in terrestrial Nostoc HK-01 and aquatic Anabaena PCC 7120 were determined. The expression of the sigJ gene in terrestrial Nostoc HK-01, which is homologous to sigJ (alr0277) in aquatic Anabaena PCC 7120, was significantly induced in the mid-stage of dehydration. We constructed a higher-expressing transformant of the sigJ gene (HE0277) in Anabaena PCC 7120, and the transformant acquired desiccation tolerance. The results of Anabaena oligonucleotide microarray experiments showed that a comparatively large number of genes relating to polysaccharide biosynthesis were upregulated in the HE0277 cells. The extracellular polysaccharide released into the culture medium of the HE0277 cells was as much as 3.2-fold more than that released by the control cells. This strongly suggests that the group 3 sigma factor gene sigJ is fundamental and conducive to desiccation tolerance in these cyanobacteria.  相似文献   
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