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61.
Interstrain differences in bitter taste responses were examinedusing inbred strains of mice. Taste responses were recordedfrom the glossopharyngeal and chorda tympani nerves of SWR/J,LP/J, BDP/J and DBA/2J mice. There were large differences inthe magnitude of responses to sucrose octaacetate (SOA) in boththe glossopharyngeal and chorda tympaninerves of SWR/J miceas compared with the other strains of mice. SOA thresholds ofSWR/J mice were 1076 M, whereas they were 104 M in LP/J mice. On the other hand, no appreciabledifferences were observed in the responses to quinine hydrochlorideand pnenyl-thio-carbamide. The results obtained in the presentexperiments fully explain the findings in behavioral studiesshowing that only SWR/J mice avoid SOA solutions whereas otherstrains do not.
*Present address: Department of Physiology, Niigata UniversitySchool of Dentistry, Niigata 951, Japan 相似文献
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63.
Summary The amount of nitrogen gas, oxygen, hydrogen, and methane in soil samples from a submerged rice field was determined using
the modified Koyama's apparatus and gas chromatography. Soils planted to rice had significantly larger amounts of nitrogen
gas than unplanted soils. The amount of N2 in a field soil increased after transplanting and reached a maximum at tillering. The amount of N2 in unplanted submerged soils did not increase significantly during the same period.
Visiting Scientist at the Institute, Professor of Soil Science, Tokyo University.
Visiting Scientist at the Institute, Professor of Soil Science, Tokyo University. 相似文献
64.
Tomio Umemoto Savitha Subramanian Yilei Ding Leela Goodspeed Shari Wang Chang Yeop Han Antonio Sta. Teresa Jinkyu Kim Kevin D. O'Brien Alan Chait 《Journal of lipid research》2012,53(11):2380-2389
Adipose tissue inflammation is associated with insulin resistance and increased cardiovascular disease risk in obesity. We previously showed that addition of cholesterol to a diet rich in saturated fat and refined carbohydrate significantly worsens dyslipidemia, insulin resistance, adipose tissue macrophage accumulation, systemic inflammation, and atherosclerosis in LDL receptor-deficient (Ldlr−/−) mice. To test whether inhibition of intestinal cholesterol absorption would improve metabolic abnormalities and adipose tissue inflammation in obesity, we administered ezetimibe, a dietary and endogenous cholesterol absorption inhibitor, to Ldlr−/− mice fed chow or high-fat, high-sucrose (HFHS) diets without or with 0.15% cholesterol (HFHS+C). Ezetimibe blunted weight gain and markedly reduced plasma lipids in the HFHS+C group. Ezetimibe had no effect on glucose homeostasis or visceral adipose tissue macrophage gene expression in the HFHS+C fed mice, although circulating inflammatory markers serum amyloid A (SSA) and serum amyloid P (SSP) levels decreased. Nevertheless, ezetimibe treatment led to a striking (>85%) reduction in atherosclerotic lesion area with reduced lesion lipid and macrophage content in the HFHS+C group. Thus, in the presence of dietary cholesterol, ezetimibe did not improve adipose tissue inflammation in obese Ldlr−/− mice, but it led to a major reduction in atherosclerotic lesions associated with improved plasma lipids and lipoproteins. 相似文献
65.
Paola Sebastiani Monty Montano Annibale Puca Nadia Solovieff Toshio Kojima Meng C. Wang Efthymia Melista Micah Meltzer Sylvia E. J. Fischer Stacy Andersen Stephen H. Hartley Amanda Sedgewick Yasumichi Arai Aviv Bergman Nir Barzilai Dellara F. Terry Alberto Riva Chiara Viviani Anselmi Alberto Malovini Aya Kitamoto Motoji Sawabe Tomio Arai Yasuyuki Gondo Martin H. Steinberg Nobuyoshi Hirose Gil Atzmon Gary Ruvkun Clinton T. Baldwin Thomas T. Perls 《PloS one》2009,4(12)
Background
The strong familiality of living to extreme ages suggests that human longevity is genetically regulated. The majority of genes found thus far to be associated with longevity primarily function in lipoprotein metabolism and insulin/IGF-1 signaling. There are likely many more genetic modifiers of human longevity that remain to be discovered.Methodology/Principal Findings
Here, we first show that 18 single nucleotide polymorphisms (SNPs) in the RNA editing genes ADARB1 and ADARB2 are associated with extreme old age in a U.S. based study of centenarians, the New England Centenarian Study. We describe replications of these findings in three independently conducted centenarian studies with different genetic backgrounds (Italian, Ashkenazi Jewish and Japanese) that collectively support an association of ADARB1 and ADARB2 with longevity. Some SNPs in ADARB2 replicate consistently in the four populations and suggest a strong effect that is independent of the different genetic backgrounds and environments. To evaluate the functional association of these genes with lifespan, we demonstrate that inactivation of their orthologues adr-1 and adr-2 in C. elegans reduces median survival by 50%. We further demonstrate that inactivation of the argonaute gene, rde-1, a critical regulator of RNA interference, completely restores lifespan to normal levels in the context of adr-1 and adr-2 loss of function.Conclusions/Significance
Our results suggest that RNA editors may be an important regulator of aging in humans and that, when evaluated in C. elegans, this pathway may interact with the RNA interference machinery to regulate lifespan. 相似文献66.
Fukaya S Shinoda C Yabe T Kanamaru Y 《Bioscience, biotechnology, and biochemistry》2010,74(10):2127-2129
Monoclonal antibody 1CF11 has been suggested to specifically recognize a certain carbohydrate epitope shared by glycoproteins in human external secretions. We examined the effect of cleaving the polypeptide backbone and removing N-linked oligosaccharides on the reactivity with 1CF11 of human milk lactoferrin (hLf) to elucidate the structural features of the 1CF11 epitope. We reveal by treating hLF with trypsin and/or N-glycosidase that both the N-glycan-relevant and N-glycan-irrelevant structural elements were involved in the recognition of hLf by 1CF11. 相似文献
67.
Tachi K Takami M Zhao B Mochizuki A Yamada A Miyamoto Y Inoue T Baba K Kamijo R 《Cell and tissue research》2010,342(2):213-220
1α,25-dihydroxyvitamin D3 [1,25(OH)2D3] induces osteoclast formation via induction of receptor activator of NF-κB ligand (RANKL, also called TNF-related activation-induced cytokine: TRANCE) in osteoblasts. In cocultures of mouse bone marrow cells and osteoblasts, 1,25(OH)2D3 induced osteoclast formation in a dose-dependent manner, with maximum osteoclast formation observed at concentrations greater than 10?9 M of 1,25(OH)2D3. In the presence of bone morphogenetic protein 2 (BMP-2), the maximum formation of osteoclasts was seen with lower concentrations of 1,25(OH)2D3 (greater than 10?11 M), suggesting that BMP-2 enhances osteoclast formation induced by 1,25(OH)2D3. In addition, the expressions of RANKL mRNA and proteins were induced by 1,25(OH)2D3 in osteoblasts, and further upregulated by BMP-2. In mouse bone marrow cell cultures without 1,25(OH)2D3, BMP-2 did not enhance osteoclast differentiation induced by recombinant RANKL and macrophage colony-stimulating factor (M-CSF), indicating that BMP-2 does not target osteoclast precursors. Furthermore, BMP-2 up-regulated the expression level of vitamin D receptor (VDR) in osteoblasts. These results suggest that BMP-2 regulates mouse osteoclast differentiation via upregulation of RANKL in osteoblasts induced by 1,25(OH)2D3. 相似文献
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70.
Yaoya S Kanho H Mikami Y Itani T Umehara K Kuroyanagi M 《Bioscience, biotechnology, and biochemistry》2004,68(9):1837-1841
Hairy root cultures of Pharbitis nil treated with CuSO4 and methyl jasmonate (MeJA) produced umbelliferone (1) and scopoletin (2) in the culture medium, and skimmin (3), a beta-D-glucopyranoside of 1, was isolated from the hairy roots. While 1 in the medium increased and reached a maximal level 16 h after the treatment with CuSO4, the amount of 3 in the hairy roots decreased, reaching a minimal level after 8 h, before recovering to a level higher than the basal level after 24 h and then continuously increasing. These observations suggest that 1 was released by the hydrolysis of 3. Umbelliferone (1) inhibited hairy root growth, while skimmin (3) did not. This result suggests that, after the release of 1 as a phytoalexin, the hairy roots glycosylated 1 for the detoxification and re-use of 3 as a source of phytoalexin. 相似文献