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71.
Sadaie T Sadaie A Takada M Hamano K Ohnishi J Ohta N Matsumoto K Sadaie Y 《Bioscience, biotechnology, and biochemistry》2007,71(3):791-799
Sludge production was reduced remarkably by reducing the dissolved oxygen supply to less than 1 mg/l in the conventional wastewater treatment procedure of a food-processing factory that produced 180 m(3) of wastewater of biochemical oxygen demand (BOD) of about 1,000 mg/l daily. DNA was extracted from the sludge and subjected to PCR amplification. The PCR product was cloned into a plasmid and sequenced. Estimation of the resident bacterial distribution by 16S rDNA sequences before and after improvement of the system suggested a remarkable gradual change in the major bacterial population from Anaerolinaeceae (15.6%) to Comamonadaceae (52.3%), members of denitrifying bacteria of Proteobacteria. Although we did not directly confirm the ability of denitrification of the resulting sludge, a change in the major final electron acceptors from oxygen to nitrate might explain the reduction in sludge production in a conventional activated sludge process when the oxygen supply was limitted. 相似文献
72.
Phosphorus-31 nuclear magnetic resonance (31P NMR) spectra ofintact cells of Scenedesmus mutant C-2A' and of their perchloricacid extracts are presented. Sugarphosphates, including glucose-6-phosphateand fructose-1,6-bisphosphate, orthophosphate, nucleotide di-and triphosphates, NAD(P), UDPG andin the case of intactcellsalso polyphosphates were identified. Blue light,which is known to stimulate the carbohydrate breakdown of greenalgae, leads to a transient drop in Pi, a pronounced decreasein the ATP/ADP ratio, and an increase in sugarphosphates, givingrise to the idea that the enhancement of phosphorolytic starchbreakdown is a primary response to blue light. Addition of glucoseto Scenedesmus mutant cells leads to comparable changes (besidesan additionally enhanced glucose-6-phosphate level), which thussupport the view that blue light stimulates dark-type respiration.Altogether the results demonstrate the applicability of 31PNMR spectroscopy to the study of the metabolism of green algae. (Received December 7, 1984; Accepted February 12, 1985) 相似文献
73.
Insufficiency of transformation by simian virus 40, polyomavirus, EJ-ras, or v-myc oncogenes for conversion of ethanolamine-responsive mammary cells to ethanolamine-nonresponsive cells.
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Normal mammary epithelial cells (ethanolamine responsive) require ethanolamine to enable them to grow in defined culture medium because they cannot synthesize de novo a sufficient amount of phosphatidylethanolamine. Mammary tumor cells which retain properties of the normal tissue are also likely to be ethanolamine responsive, whereas dedifferentiated, highly tumorigenic mammary tumor cells are ethanolamine nonresponsive. The nonresponsive tumor cells are able to synthesize the necessary amount of phosphatidylethanolamine to sustain growth. Therefore, the progression of malignancy seems to convert ethanolamine-responsive mammary cells to ethanolamine-nonresponsive ones. In an attempt to prove the above assumption and to understand the mechanism responsible for the conversion during the progression of malignant transformation, mammary tumor cell line 64-24, which is typically ethanolamine responsive, was transfected with simian virus 40, polyomavirus, EJ-ras, or v-myc oncogenes, and the resulting transfectants were examined for their growth response to ethanolamine. Many of the transfectants exhibited typical transformed phenotypes; however, none of the transfectants converted to ethanolamine-nonresponsive cells. Some of the SV40 and polyomavirus transformants were able to grow in the absence of ethanolamine, although they grew better in the presence of ethanolamine, unlike typical ethanolamine-nonresponsive cells. These cells could grow in the absence of ethanolamine, even though their membrane phospholipid was phosphatidylethanolamine deficient. The present study indicates that the expression of any one of the four oncogenes tested, which allows the cells to exhibit transformed phenotypes in 64-24 cells, is not sufficient for the conversion of ethanolamine-responsive cells to -nonresponsive cells. 相似文献
74.
Cells of epithelial origin generally require ethanolamine (Etn) to grow in defined culture medium. When such cells are grown without Etn, the membrane phospholipid composition changes drastically, becoming phosphatidylethanolamine (PE)-deficient due to a reduced de novo rate of PE synthesis, and growth stops. We have hypothesized that the cessation of growth occurs because this membrane phospholipid environment is no longer suitable for membrane-associated functions. Phospholipid has long been known to play a role in the transduction of some signals across membranes. In addition to the well-known phosphatidylinositol cycles, hydrolysis of phosphatidylcholine (PC) and PE has recently been shown to play a central role in signal transduction. Using an Etn-requiring rat mammary cell line 64-24, we have studied the metabolism of PC and PE in response to the phorbol ester phorbol 12,13-dibutyrate (PDBu) under conditions where cells have either normal or PE-deficient membrane phospholipid. In cells having normal membrane phospholipid, the synthesis of PC was stimulated by PDBu (approximately fourfold), as was the degradation of PC and PE (by twofold and fourfold, respectively). Product analysis suggested that PDBu stimulated hydrolysis of PC by both phospholipases C and D (PLC and PLD), and of PE by PLD. However, in PE-deficient cells, neither lipid synthesis or degradation were significantly stimulated by PDBu. Analysis of the CDP-choline pathway of PC synthesis indicated that the regulatory enzyme, CTP:phosphorylcholine cytidylyltransferase, was stimulated about twofold by PDBu in cells having normal membrane, but not in PE-deficient cells. These results indicate that the membrane phospholipid environment profoundly affects phospholipid metabolism, which no doubt influences cell growth and regulation. 相似文献
75.
Bone marrow analysis of the myelodysplastic syndromes: histological and immunohistochemical features related to the evolution of overt leukemia 总被引:3,自引:0,他引:3
Masanobu Kitagawa Ryuichi Kamiyama Tamiko Takemura Tsutomu Kasuga 《Virchows Archiv. B, Cell pathology including molecular pathology》1989,57(1):47-53
Bone marrow trephines from 31 patients with an initial diagnosis of myelodysplastic syndromes (MDS) were examined and analyzed histologically and immunohistochemically. In those cases terminating in overt leukemia (6/31, 19%), the number of bone marrow mast cells was significantly reduced, compared with those which did not evolve to overt leukemia. The bone marrow lymphoid cells that may participate in immunosurveillance against the proliferation of blast cells were also significantly reduced in cases terminating in overt leukemia. However, S-100 protein-positive cells, which include histiocytes and suppressor T-cells, were increased in cases terminating in overt leukemia. The results indicated that examination of the bone marrow to determine the proportions of mast cells and lymphoid cells which may be involved in host defense systems may be useful in predicting the evolution to overt leukemia in MDS. In the present series, patients with a hypocellular marrow (5/31, 16%) did not progress to overt leukemia and had a significantly lower bone marrow reticulin content, a significantly lower megakaryocyte count, a relatively higher mast cell count and a significantly higher lymphoid cell count than those with a normocellular or hypercellular marrow. These findings may reflect the initial features of MDS or, possibly, that hypocellular MDS is an independent entity with a low potential for blastic proliferation. 相似文献
76.
Focal disturbed laminar architecture in cerebellar vermis was observed in 25 out of 100 (25%) males, and 25 out of 100 (25%) females of BrlHan: WIST@Jcl rats. The cortical molecular and granular layers were haphazardly distributed around the primary and/or secondary fissures. The stellate and basket cells positively stained with parvalbumin immunohistochemistry were observed exclusively in the separated molecular layer. Purkinje cells were found at the boundary between the molecular and the granular layers. Glial fibrillary acid protein (GFAP) immunohistochemistry revealed disarranged fibers of the Bergman glial cells. Based on the incidence of this spontaneous cerebellar lesion, it was presumed to be related to certain genetic factors of this rat strain. 相似文献
77.
Kenji Okuda Tamiko Kaneko Tadashi Yamakawa Shunichi Tanaka Takashi Shigematsu Akihiro Yamamoto Kenji Hamajima Kiichiro Nakajima Susumu Kawamoto Praphan Phanuphak 《Journal of molecular recognition : JMR》1993,6(3):101-109
We synthesized one V3 peptide each from HTLV-IIIB, Thai A and Thai B, conjugating then to the T cell epitope of the env region, and we also synthesized a p17 protein peptide of the gag region (HGP-30). These peptide were then coupled to 8-lysine copolymers using N-succinimidyl maleimido carboxylate (Mr = ca 60 000). We designated this the branched lysine oligopeptide method. The large peptide complexes constructed from these four macromolecular peptide were used with aluminium hydroxide or complete Freund's adjuvant to immunize mice and rabbits four times. ELISA assay with aluminium hydroxide or complete Freund's adjuvant to immunize mice and rabbits four times. ELISA assay showed high titres of anti-peptide antibodies to each V3loop peptide and the HGP-30 peptide. Strong inhibition of CD4+ dependent cell fusion was obtained with these antisera when IIIb, Thai A and Thai B strains of human immunodeficiency virus (HIV) were used. Strong anti-fusion inhibition was also observed with two other HIV strains. In addition, an increase of the anti-HIV effect was observed when we used sera obtained by multicomponent vaccine immunization. The same kind of inhibition was also observed in p24 assay systems using these immunized antisera. Activation of IL-2 production in lymphocytes was observed in p24 assay systems using these immunized antisera. Activation of IL-2 production in lymphocytes was observed in mice immunized with this vaccine. These results suggest that immunization with macromolecular peptide complexes can result in strong immunogenicity towards HIV-1. 相似文献
78.
Nakajima T Yasuda T Takeshita H Mori S Mogi K Kaneko Y Nakazato E Kishi K 《Biochimica et biophysica acta》2002,1570(3):160-164
Four murine monoclonal anti-human deoxyribonuclease II (DNase II) antibodies were obtained from BALB/c mice immunized with human DNase II purified from human liver. Both single radial enzyme diffusion (SRED) and DNA-cast polyacrylamide gel electrophoresis (DNA-cast PAGE) were very useful for obtaining the DNase II-specific antibodies. All of the antibodies showed specific inhibition of human DNase II enzyme activity and specific immunostaining of the 32-kDa enzyme band, which is one of the three non-identical subunits of human DNase II molecule separated by sodium dodecyl sulfate (SDS)-PAGE followed by blotting on a transfer membrane. A formyl-cellulofine resin conjugated with each antibody specifically adsorbed and efficiently desorbed the active DNase II enzyme. Insertion of the immunoaffinity step in our purification procedure made the purification of human DNase II easier, faster and more effective than the conventional procedure. 相似文献
79.
Iwasaki T Murata M Ohshima S Miyake T Kudo S Inoue Y Narita M Yoshimura T Akiba S Tango T Yoshimoto Y Shimizu Y Sobue T Kusumi S Yamagishi C Matsudaira H 《Radiation research》2003,159(2):228-238
IA cohort study of nuclear industry workers was initiated in 1990 to determine the possible health effects of low-level radiation. A total of 5,527 deaths were ascertained among 176,000 male workers who had been retrospectively and/or prospectively followed for an average of 7.9 years during the observation period 1986-1997. Statistical analyses were made mainly on the prospective follow-up outcome of 120,000 workers followed for an average of 4.5 years. The standardized mortality ratio (and its 95% confidence interval) was 0.94 (0.90, 0.97) for 2,934 cases of all causes combined and 0.86 (0.82, 0.91) for 1,305 cases of non-malignant diseases combined, which suggested a healthy worker effect. For 1,191 cases of all cancers combined, it was 0.98 (0.93, 1.04), indicating no difference in mortality from that of the general population. In tests for trend of death rate with increasing radiation dose, no significant correlation was found for all cancers combined. For site-specific cancers, most cancers including leukemia showed no positive correlation with dose, except for cancers of the esophagus, stomach and rectum and multiple myeloma. External causes showed a significant correlation with dose. A separate questionnaire study indicated that these positive findings could be ascribed in part to lifestyle characteristics of the workers. For leukemia only, we attempted to estimate the excess relative risk per unit dose of radiation, which, with reservations because of its wide confidence interval, was within the range of variation of the risks reported in other radiation epidemiological studies. This population must be studied for a longer time and with a consideration of the possible effects of confounding factors. 相似文献
80.
Yasunari Miyazaki Koji Unoura Tomoya Tateishi Takumi Akashi Tamiko Takemura Makoto Tomita Naohiko Inase Yasuyuki Yoshizawa 《Respiratory research》2013,14(1):57