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81.
Effects of TNF on human hepatocellular carcinoma cell lines and their modification by hyperthermia 总被引:1,自引:0,他引:1
S Hasumura S Nagamori K Fujise S Homma H Sujino T Matsuura K Shimizu M Niiya H Kameda N Satomi 《Human cell》1988,1(2):238-244
Firstly, using HCC cell lines, the effects of r-h TNF were investigated. The authors had already confirmed that these cell lines were derived from human HCC. Each cell line showed a different growth curve on addition of TNF to the culture medium. JHH-4 exhibited enhancement of growth under the optimum concentration of TNF. On the other hand, growth of JHH-5 and JHH-7 was inhibited by TNF. JHH-7 were more sensitive to TNF than JHH-5, however, the direct effect of TNF on JHH-7 was not potent, as 10(4) u/ml TNF could not prevent proliferation of JHH-7. Morphological examinations were also performed. Phase-contrast microscopy showed that the JHH-4 cells were enlarged and tended to pile up after the addition of TNF to the culture medium. JHH-7 cells became detached from the culture dish due to cell death. Electron microscopy showed irregular proliferation of the rough endoplasmic reticulum of JHH-4 cells and increased number of lysosomes in JHH-7 cells. Furthermore, hyperthermia exhibited an interesting reciprocal action. Proliferation of JHH-4 was inhibited by low concentrations of TNF together with 41.4 degrees C hyperthermia in contrast to the effects of TNF alone. JHH-7 became more sensitive to TNF under hyperthermia at 41.4 degrees C. On the other hand, normal human fibroblast 'HAIN-55' were not affected by TNF at 37.0 degrees C, 41.4 degrees C or 42.5 degrees C. In this paper, the authors tried to study the effects of TNF and hyperthermia on human HCC cell lines.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
82.
A human hepatocellular carcinoma cell line, JHH-4 was established from resected liver tumor. Morphological diagnosis of the original tumor was hepatocellular carcinoma, Edmondson type III. This cell line was composed of polygonal shaped cells. Subcellular organelle were observed in cytoplasm. Furthermore, bile canaliculi adhering junction was also remained at the cell surface. The growth rate of JHH-4 cell is slow, peaks of the chromosome number was 75 and 79, and plating efficiency was 3.0%. JHH-4 cell is transplantable to nude mouse. Furthermore, this cell line functionally synthesized and secreted human albumin, AFP and other proteins in vitro. 相似文献
83.
84.
Hideaki Fujita Akiko Endo Kazunori Shimizu Eiji Nagamori 《Biotechnology and bioengineering》2010,107(5):894-901
We have compared several serum‐free media for the differentiation of C2C12 myoblasts and assessed the extent of differentiation in several ways including as to active tension generation capability. C2C12 cells were allowed to differentiate in Dulbecco's modified Eagle's medium (DMEM) containing Ham's F‐12 (F‐12), AIM‐V (AIM), 0.2% Ultroser‐G in DMEM (Ult‐G), and 0.1% Sericin in DMEM (Sericin), compared with in DMEM supplemented with 2% horse serum (HS) or 2% calf serum (CS). C2C12 differentiation was assessed as the extent of myotube formation, glucose metabolism, protein expression, sarcomere formation, and active tension generation. All serum‐free media examined were capable of inducing myotube formation and the expression of muscle‐specific proteins. All serum‐free media except for F‐12 gave the sarcomere structure. Active tension generation was observed for cells that differentiated in AIM and Ult‐G, but the active tension generated by C2C12 cells that differentiated in Ult‐G was only ~25% in the case of myotubes that formed in HS. The addition of Ult‐G to the AIM resulted in improvement of the active tension generation capability, the active tension generated being ~3.4× compared to that in HS. The approach for assessing muscle cell differentiation presented in this study will be suitable for other studies that involve the differentiation of muscle cells. Biotechnol. Bioeng. 2010;107: 894–901. © 2010 Wiley Periodicals, Inc. 相似文献
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86.
红树植物内生菌在红树共生体的物质循环、能量传递和健康维护等方面起着重要作用。为探究红树植物内生菌的多样性,进一步揭示内生菌在红树共生体的功能多样性提供菌种资源,该研究选择6种分离培养基和采用传统稀释涂布法对从广西北海滩涂上采集的桐花树组织和根际土壤样品进行分离,对获得的可培养细菌进行多样性分析,并通过体外溶栓实验筛选出具有抗血栓活性的菌株。结果表明:(1)基于16S rRNA基因序列系统进化分析,从桐花树组织和根际土壤中共获得125株细菌;分布于变形菌门(Proteobacteria)、放线菌门(Actinobacteria)和厚壁菌门(Firmicutes) 3个门27个科39个属74个种中,芽孢杆菌属为优势菌属,菌株数量占13.5%。(2)抗血栓活性实验表明,初筛获得18株具有抗血栓活性细菌,总阳性率为24.32%;将初筛有活性的菌株进行复筛和重复验证实验,进一步验证其活性,结果复筛出3株细菌B1850、B1989和B2632具有很强抗血栓活性。综上所述,广西北海滩涂上红树植物桐花树中存在丰富的可培养细菌资源,具有从中挖掘新的纤溶酶和开发溶血栓药物的潜力。 相似文献
87.
Yue He Shushi Peng Yongwen Liu Xiangyi Li Kai Wang Philippe Ciais M. Altaf Arain Yuanyuan Fang Joshua B. Fisher Daniel Goll Daniel Hayes Deborah N. Huntzinger Akihiko Ito Atul K. Jain Ivan A. Janssens Jiafu Mao Campioli Matteo Anna M. Michalak Changhui Peng Josep Peuelas Benjamin Poulter Dahe Qin Daniel M. Ricciuto Kevin Schaefer Christopher R. Schwalm Xiaoying Shi Hanqin Tian Sara Vicca Yaxing Wei Ning Zeng Qiuan Zhu 《Global Change Biology》2020,26(3):1474-1484
Plants use only a fraction of their photosynthetically derived carbon for biomass production (BP). The biomass production efficiency (BPE), defined as the ratio of BP to photosynthesis, and its variation across and within vegetation types is poorly understood, which hinders our capacity to accurately estimate carbon turnover times and carbon sinks. Here, we present a new global estimation of BPE obtained by combining field measurements from 113 sites with 14 carbon cycle models. Our best estimate of global BPE is 0.41 ± 0.05, excluding cropland. The largest BPE is found in boreal forests (0.48 ± 0.06) and the lowest in tropical forests (0.40 ± 0.04). Carbon cycle models overestimate BPE, although models with carbon–nitrogen interactions tend to be more realistic. Using observation‐based estimates of global photosynthesis, we quantify the global BP of non‐cropland ecosystems of 41 ± 6 Pg C/year. This flux is less than net primary production as it does not contain carbon allocated to symbionts, used for exudates or volatile carbon compound emissions to the atmosphere. Our study reveals a positive bias of 24 ± 11% in the model‐estimated BP (10 of 14 models). When correcting models for this bias while leaving modeled carbon turnover times unchanged, we found that the global ecosystem carbon storage change during the last century is decreased by 67% (or 58 Pg C). 相似文献
88.
Y. Kawamura H. Matsuo T. Chiba S. Nagamori A. Nakayama H. Inoue 《Nucleosides, nucleotides & nucleic acids》2013,32(12):1105-1111
Renal hypouricemia (MIM 220150) is an inherited disorder characterized by low serum uric acid levels and has severe complications such as exercise-induced acute renal failure and urolithiasis. We have previously reported that URAT1/SLC22A12 encodes a renal urate-anion exchanger and that its mutations cause renal hypouricemia type 1 (RHUC1). With the large health-examination database of the Japan Maritime Self-Defense Force, we found two missense mutations (R198C and R380W) of GLUT9/SLC2A9 in hypouricemia patients. R198C and R380W occur in highly conserved amino acid motifs in the “sugar transport proteins signatures” that are observed in GLUT family transporters. The corresponding mutations in GLUT1 (R153C and R333W) are known to cause GLUT1 deficiency syndrome because arginine residues in this motif are reportedly important as the determinants of the membrane topology of human GLUT1. Therefore, on the basis of membrane topology, the same may be true of GLUT9. GLUT9 mutants showed markedly reduced urate transport in oocyte expression studies, which would be the result of the loss of positive charges in those conserved amino acid motifs. Together with previous reports on GLUT9 localization, our findings suggest that these GLUT9 mutations cause renal hypouricemia type 2 (RHUC2) by their decreased urate reabsorption on both sides of the renal proximal tubule cells. However, a previously reported GLUT9 mutation, P412R, was unlikely to be pathogenic. These findings also enable us to propose a physiological model of the renal urate reabsorption via GLUT9 and URAT1 and can lead to a promising therapeutic target for gout and related cardiovascular diseases. 相似文献
89.
Eiji Nagamori Kazunori Shimizu Hideaki Fujita Kenro Tokuhiro Nobuhiro Ishida Haruo Takahashi 《Bioprocess and biosystems engineering》2013,36(9):1261-1265
In the present study, to elucidate mechanisms of growth suppression in YIBO-pdc1/5Δ, we performed carbon metabolic flux analysis under micro-aerobic conditions. Our results indicate that growth suppression of YIBO-pdc1/5Δ is caused by decreased flux to the pentose phosphate pathway, which supplies ribose-5-phosphate, a precursor for histidine synthesis in Sacchar omyces cerevisiae. In addition, significant accumulation of pyruvate was observed in the continuous culture. 相似文献
90.
Dominant regions and drivers of the variability of the global land carbon sink across timescales 下载免费PDF全文
Xuanze Zhang Ying‐Ping Wang Shushi Peng Peter J. Rayner Philippe Ciais Jeremy D. Silver Shilong Piao Zaichun Zhu Xingjie Lu Xiaogu Zheng 《Global Change Biology》2018,24(9):3954-3968
Net biome productivity (NBP) dominates the observed large variation of atmospheric CO2 annual increase over the last five decades. However, the dominant regions controlling inter‐annual to multi‐decadal variability of global NBP are still controversial (semi‐arid regions vs. temperate or tropical forests). By developing a theory for partitioning the variance of NBP into the contributions of net primary production (NPP) and heterotrophic respiration (Rh) at different timescales, and using both observation‐based atmospheric CO2 inversion product and the outputs of 10 process‐based terrestrial ecosystem models forced by 110‐year observational climate, we tried to reconcile the controversy by showing that semi‐arid lands dominate the variability of global NBP at inter‐annual (<10 years) and tropical forests dominate at multi‐decadal scales (>30 years). Results further indicate that global NBP variability is dominated by the NPP component at inter‐annual timescales, and is progressively controlled by Rh with increasing timescale. Multi‐decadal NBP variations of tropical rainforests are modulated by the Pacific Decadal Oscillation (PDO) through its significant influences on both temperature and precipitation. This study calls for long‐term observations for the decadal or longer fluctuations in carbon fluxes to gain insights on the future evolution of global NBP, particularly in the tropical forests that dominate the decadal variability of land carbon uptake and are more effective for climate mitigation. 相似文献