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21.
Kotaro Hama Yuko Fujiwara Masashi Morita Fumiyoshi Yamazaki Yuko Nakashima Shiro Takei Shigeo Takashima Mitsutoshi Setou Nobuyuki Shimozawa Tsuneo Imanaka Kazuaki Yokoyama 《Lipids》2018,53(1):85-102
ABCD1 is a gene responsible for X‐linked adrenoleukodystrophy (X‐ALD), and is critical for the transport of very long‐chain fatty acids (VLCFA) into peroxisomes and subsequent β‐oxidation. VLCFA‐containing lipids accumulate in X‐ALD patients, although the effect of ABCD1‐deficiency on each lipid species in the central nervous system has not been fully characterized. In this study, each phospholipid and lysophospholipid species in Abcd1‐deficient mice brains were profiled by liquid chromatography‐mass spectrometry. Among the phospholipid and lysophospholipid species that are significantly more enriched in Abcd1‐deficient mice brains, VLCFA were present in 75, 15, 5, 4, and 1 species of phosphatidylcholine, phosphatidylethanolamine, sphingomyelin, lysophosphatidylcholine, and lysophosphatidylethanolamine, respectively. Most VLCFA were incorporated at the sn‐1 position of phosphatidylcholine and phosphatidylethanolamine. Among the phospholipid species that are significantly less enriched in Abcd1‐deficient mice brains, odd‐numbered saturated or mono‐unsaturated fatty acyl moieties are contained in all phosphatidylcholine species. In addition, a number of phosphatidylglycerol, phosphatidylinositol, and phosphatidylserine species contained highly unsaturated fatty acyl moieties. Intriguingly, 44:1 phosphatidylcholine with VLCFA was mainly distributed in the gray matter, such as the cortex, but not in the white matter in the cerebrum and cerebellum. These results show that ABCD1‐deficiency causes metabolic alternation of long‐chain fatty acids and VLCFA. Moreover, our results imply a molecular mechanism for the incorporation of saturated or monounsaturated VLCFA into the sn‐1 position of phospholipids, and also indicate that the distribution of phospholipids with VLCFA may correlate with the development of X‐ALD. 相似文献
22.
Viliame Savou Guido Grause Shogo Kumagai Yuko Saito Tomohito Kameda Toshiaki Yoshioka 《能源学会志》2019,92(4):1149-1157
Pyrolysis is a promising technique for the recovery of useful gas, tar, and solid products from biomass waste. However, the low tar yields obtained from lignocellulosic biomass are a significant drawback. To enhance tar yields, sugarcane bagasse, which is the most abundant agricultural waste in Fiji, was pretreated at ambient temperature and atmospheric pressure using various sulfuric acid (H2SO4) concentrations. Here, the ether bonds of cellulose, hemicellulose, and lignin were partially hydrolyzed. The pretreated samples were then pyrolyzed at 500 °C, and it was confirmed that H2SO4-pretreatment disrupted the bagasse cell structure, with the thermogravimetry and differential thermogravimetry results confirming that decomposition occurred at lower temperatures after pretreatment. In addition, tar yields were significantly enhanced from 5.6 wt% to 13.4 wt% for the untreated and 3 M H2SO4-pretreated samples respectively. The main components detected in this tar product were levoglucosan, andcellulose-and hemicellulose-derived products, whose proportions were increased following pretreatment. Thus, our work demonstrates that dilute acid pretreatment enhances tar production from sugarcane bagasse due to the production of shorter chain components via the partial hydrolysis of ether bonds. 相似文献
23.
A hybrid adsorption heat pump water heater has been studied for domestic use. It is a water heater with dual heat sources, and it combines the performances of adsorption heat pumps and conventional gas boilers. Moreover, functional adsorbent material‐zeolite (FAM‐Z02, Mitsubishi Chemicals) and water are a new adsorption pair for adsorption heat pumps. This article describes the operation, design, and performance analysis of one such water‐heating device. The experimental results showed that the hybrid water heater in the whole year has a stable COP even at low ambient temperature. The hybrid water heater can thus achieve high energy efficiency. 相似文献
24.
Sakai K Mori M Fujii A Iwami Y Chukeatirote E Shirai Y 《Journal of Bioscience and Bioengineering》2004,98(1):48-56
Reproducible amounts of lactic acid accumulate in minced kitchen refuse under open conditions with intermittent pH neutralization [Sakai et al., Food Sci. Technol. Res., 6, 140 (2000)]. Here, we showed that such pH-controlled open fermentation of kitchen refuse reproducibly resulted a selective proliferation of a major lactic acid bacterial (LAB) species. In one experiment, the predominant microorganisms isolated during the early phase (6 h) were Gammaproteobacteria. In contrast, those that predominated during the late phase (48 h) were always Lactobacillus plantarum in three independent experiments. To further quantify the microbial community within open lactic acid fermentation, we performed fluorescent in situ hybridization (FISH) analysis targeting 16S (23S) rRNA. We designed two new group-specific DNA probes: LAC722(L) was active for most LAB including the genera Lactobacillus, Pediococcus, Leuconostoc and Weisella, whereas Lplan477 was specific for L. plantarum and its related species. We then optimized sample preparation using lysozyme and hybridization conditions including temperature, as well as the formamide concentration and the salt concentration in the washing buffer. We succeeded in quantification of microorganisms in semi-solid, complex biological materials such as minced kitchen refuse by taking color microphotographs in modified RGB balance on pre-coated slides. FISH analysis of the fermentation of kitchen refuse indicated that control of the pH swing leads to domination by the LAB population in minced kitchen refuse under open conditions. We also confirmed that L. plantarum, which generates lactic acid in high quantities but with low optical activity, became the dominant microorganism in kitchen refuse during the late phase of open fermentation. 相似文献
25.
Keiichi Miyamoto Ayaka Kawasaki Yuko Nagata Masanori Uraya Hisayoshi Kojima Takanori Ito Takashi Horiuchi Nagisa Asakawa Shinsuke Nomura 《Materials science & engineering. C, Materials for biological applications》2011,31(2):158-165
Immunoglobulin A1 (IgA1) concentration in the plasma of patients with IgA nephropathy (IgAN) as the cause of renal failure is higher than that in the plasma of normal controls. IgA1 with abnormal sugars is considered to deposit in the glomerular mesangium, aggravating nephritis in IgAN. Jacalin is a lectin that recognizes sugars on IgA1. However, its selective-recognition for normal-type (ST type, NeuAc-α(2,3)-Gal-β(1,3)-GalNAc) and abnormal-type (T type, Gal-β(1,3)-GalNAc; Tn type, GalNAc; STn type, NeuAc-α(2,6)-GalNAc) sugars α-O-linked to serine/threonine in IgA1 is weak. Therefore, jacalin cannot be used for recognizing specific sugar types on IgA1. We attempted to develop a new recognition method for specific sugar types on IgA1 by utilizing the multirecognition capability of jacalin. Its binding abilities were regulated by heat denaturation with suitable template sugar (galactose or N-acetylgalactosamine). Further, we successfully prepared denatured-jacalin derivatives, which recognized ST-/T-type sugars on IgA1, by sugar-immobilized affinity chromatography. Enzyme-linked immunosorbent assay of denatured-jacalin derivatives, showed the ratios of abnormal sugars on IgA1 in the plasma of IgAN patients and normal controls to be approximately 60% and 20%, respectively. The results proved that profiling of sugar types in IgAN can successfully be performed by solely using jacalin derivatives. 相似文献
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28.
Silicon nitride (Si3N4) whiskers were synthesized from SiO2-N2-Na3AlF6 system. Whiskers, which were synthesized when the molar ratio of SiO2 to Na3AlF6 (SiO2/Na3AlF6) ranged from 2 to 8, were prismatic with a stable diameter ranging from 0.1 to 0.5 m. Therefore, the whiskers were considered to have grown by a VS mechanism. The effect of the addition of iron oxide (Fe2O3 : SiO2 = 1.5–7.5 : 100) was examined when SiO2/Na3AlF6 was 3, at which the maximum amount of whiskers was obtained. Since some of the whiskers, synthesized when the weight of Fe2O3 to that of SiO2 ranged from 3.0 to 6.25 (Fe2O3 : SiO2 = 3.0–6.25 : 100), have droplets on their tips, they were assumed to have grown by VS and VLS mechanisms. The composition of the droplets were found to be Al-Si by elemental analysis by EDAX. Since droplets composed of Al-Si have never been reported, we performed a detailed analysis of the droplets in this study. 相似文献
29.
T Iwanaga R Kishikawa T Ikeda T Hirose H Tsurutani S Yoshida 《Canadian Metallurgical Quarterly》1998,73(10):579-584
Pulmonary mycobacteriosis is usually caused by Mycobacterium tuberculosis, Mycobacterium avium complex, or Mycobacterium kansasii. There are, however, other slow-growing mycobacteria which can cause pulmonary infection. Mycobacterium szulgai, first reported in 1972, is a scotochromogenic species which can affect human lungs, although human-to-human spread of infection is thought to be unlikely. We have recently treated three cases of middle-aged to elderly persons (45-87 year-old), two of them had underlying diseases (one with intrapulmonary and the other with extrapulmonary). All patients had constitutional symptoms (cough, sputum, dyspnea), and chest roentgenograms demonstrated either cavitation with scattered nodules or peripheral infiltrates predominantly in upper lobes, resembling pulmonary tuberculosis. In two cases, M. szulgai was identified by using DNA-DNA hybridization method. The in vitro susceptibility of M. szulgai to antimycobacterial drugs was better than that of M. avium complex, and it was resistant only to paraaminosalicylate, cycloserine, and partially to isoniazid. Pulmonary disease of three patients were successfully treated with a combination of multiple antimycobacterial agents including rifampin, ethambutol, isoniazid, or streptomycin. 相似文献
30.
RT Matheson DR Miller MJ Lacombe YN Han S Iwanaga H Kato KD wuepper 《Canadian Metallurgical Quarterly》1976,58(6):1395-1406
Flaujeac trait is the functional deficiency of a plasma protein of the intrinsic coagulation, kinin-forming, and plasma fibrinolytic pathways. The Flaujeac factor in man has been isolated and tentatively identified as a kininogen of high molecular weight (HMW). Highly purified bovine HMW-kininogen, but not bovine low molecular weight kininogen, repaired Flaujeac factor deficiency. The two subspecies of this molecule, HMW-kininogen a and HMW-kininogen b, also corrected Flaujeac factor deficiency. When bovine HMW-kininogen was incubated with bovine plasma kallikrein, kinin-free HMW-kininogen, bradykinin, and a glycopeptide fragment (peptide 1-2; 12,584 daltons) were rapidly released. None of these fragmentation products corrected Flaujeac factor deficiency alone or in mixtures. The function of HMW-kininogen appeared to depend upon the structural integrity of the native molecule. When injected in concentrations of 2 pmol-8 nmol/0.1 ml, peptide 1-2 caused increased vascular permeability in rabbits, rats, or guinea pigs. The enhanced permeability was maximal within 1-2 min and terminated in 5-10 min, differing from that of bradykinin or histamine. Injected together in equimolar amounts, peptide 1-2 and bradykinin produced a synergistic permeability response which was immediate in onset as well as prolonged in duration. Peptide 1-2 is a rapidly acting, highly basic glyco-peptide which mediates increased vascular permeability in a complementary and synergistic manner with bradykinin. 相似文献