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71.
Annals of Telecommunications - This paper presents a new consensus algorithm, Proof of Usage (PoU), for the blockchain technology. This consensus is introduced for permissioned (or private)... 相似文献
72.
Fokion Papathanasiou Samuel H Mitchell Barbara M R Harvey 《Journal of the science of food and agriculture》1999,79(1):32-36
Individual tubers from mature plants of cultivars Pentland Dell and Estima were harvested from experimental plots in two successive years and analysed for α‐solanine, α‐chaconine and total glycoalkaloid concentration (α‐solanine and α‐chaconine combined) using high‐performance liquid chromatography. Mean tuber glycoalkaloid concentration per plant was strongly affected by genotype and was much higher in plants of Pentland Dell (10.0 and 16.3 mg per 100 g fresh weight in 1994 and 1995, respectively) than Estima (4.0 and 4.3 mg per 100 g fresh weight in 1994 and 1995, respectively). The variation between plants in mean tuber glycoalkaloid concentration, expressed as coefficient of variation, was similar for the two cultivars in both years. Variation within plants was higher for cultivar Pentland Dell than Estima for both years but it was statistically significant only in 1995. Tuber position within a plant had no effect on glycoalkaloid concentrations in tubers of similar size. An inverse relationship between total glycoalkaloid concentration and tuber fresh weight of individual tubers was found for both cultivars and small tubers of Pentland Dell (20–40 g fresh weight) exceeded the safety limit of 20 mg per 100 g fresh weight. The pattern of glycoalkaloid accumulation differed between genotypes and appeared related to tuber growth. The implications of these results in terms of food safety are discussed. © 1999 Society of Chemical Industry 相似文献
73.
Se Eun Ha Brian G. Jorgensen Lai Wei Byungchang Jin Min-Seob Kim Sandra M. Poudrier Rajan Singh Allison Bartlett Hannah Zogg Sei Kim Gain Baek Masaaki Kurahashi Moon-Young Lee Yong-Sung Kim Suck-Chei Choi Kent C. Sasse Samuel J. S. Rubin Andres Gottfried-Blackmore Laren Becker Aida Habtezion Kenton M. Sanders Seungil Ro 《International journal of molecular sciences》2022,23(9)
Metalloendopeptidase ADAM-Like Decysin 1 (ADAMDEC1) is an anti-inflammatory peptidase that is almost exclusively expressed in the gastrointestinal (GI) tract. We have recently found abundant and selective expression of Adamdec1 in colonic mucosal PDGFRα+ cells. However, the cellular origin for this gene expression is controversial as it is also known to be expressed in intestinal macrophages. We found that Adamdec1 mRNAs were selectively expressed in colonic mucosal subepithelial PDGFRα+ cells. ADAMDEC1 protein was mainly released from PDGFRα+ cells and accumulated in the mucosal layer lamina propria space near the epithelial basement membrane. PDGFRα+ cells significantly overexpressed Adamdec1 mRNAs and protein in DSS-induced colitis mice. Adamdec1 was predominantly expressed in CD45− PDGFRα+ cells in DSS-induced colitis mice, with only minimal expression in CD45+ CD64+ macrophages. Additionally, overexpression of both ADAMDEC1 mRNA and protein was consistently observed in PDGFRα+ cells, but not in CD64+ macrophages found in human colonic mucosal tissue affected by Crohn’s disease. In summary, PDGFRα+ cells selectively express ADAMDEC1, which is localized to the colon mucosa layer. ADAMDEC1 expression significantly increases in DSS-induced colitis affected mice and Crohn’s disease affected human tissue, suggesting that this gene can serve as a diagnostic and/or therapeutic target for intestinal inflammation and Crohn’s disease. 相似文献
74.
Patrik Palacka Anna Gvozdjkov Zuzana Rausov Jarmila Kucharsk Jn Slopovský Jana Obertov Daniel Furka Samuel Furka Keshav K. Singh Zuzana Sumbalov 《International journal of molecular sciences》2022,23(1)
Mitochondrial bioenergetics reprogramming is an essential response of cells to stress. Platelets, an accessible source of mitochondria, have a crucial role in cancer development; however, the platelet mitochondrial function has not been studied in urothelial carcinoma (UC) patients. A total of 15 patients with UC and 15 healthy controls were included in the study. Parameters of platelet mitochondrial respiration were evaluated using the high-resolution respirometry method, and the selected antioxidant levels were determined by HPLC. In addition, oxidative stress was evaluated by the thiobarbituric acid reactive substances (TBARS) concentration in plasma. We demonstrated deficient platelet mitochondrial respiratory chain functions, oxidative phosphorylation (OXPHOS), and electron transfer (ET) capacity with complex I (CI)-linked substrates, and reduced the endogenous platelet coenzyme Q10 (CoQ10) concentration in UC patients. The activity of citrate synthase was decreased in UC patients vs. controls (p = 0.0191). γ-tocopherol, α-tocopherol in platelets, and β-carotene in plasma were significantly lower in UC patients (p = 0.0019; p = 0.02; p = 0.0387, respectively), whereas the plasma concentration of TBARS was increased (p = 0.0022) vs. controls. The changes in platelet mitochondrial bioenergetics are consistent with cell metabolism reprogramming in UC patients. We suppose that increased oxidative stress, decreased OXPHOS, and a reduced platelet endogenous CoQ10 level can contribute to the reprogramming of platelet mitochondrial OXPHOS toward the activation of glycolysis. The impaired mitochondrial function can contribute to increased oxidative stress by triggering the reverse electron transport from the CoQ10 cycle (Q-junction) to CI. 相似文献
75.
Samuel J.A. Guieu Anna Maria Manotti Lanfredi Chiara Massera Laura Durn Pachn Patrick Gamez Jan Reedijk 《Catalysis Today》2004,96(4):259-264
Poly(2,6-dimethyl-1,4-phenylene ether) (PPE), which is widely used in high-performance engineering plastics, is obtained by the copper-catalyzed oxidative coupling of 2,6-dimethylphenol. The oxidative polymerizations have been carried out in acetonitrile with structurally related [copper-(N,O-containing ligand)] complexes as the catalyst precursor compounds, which appeared to be of great interest for a better understanding of the factors influencing the catalytic activities. Steric effects (influence of a methyl group close to the metal center; ligands 4–7) or electronic effects (imino versus amino group; ligands 4, 5, 8 and 6, 7, 9, respectively) on the polymerization rates have been demonstrated. The use of mono- or dinucleating ligands has strengthened the proposed mechanism of the reaction involving dinuclear active species. 相似文献
76.
Enterotoxigenic <Emphasis Type="Italic">Escherichia coli</Emphasis> strains bind bovine milk gangliosides in a ceramide-dependent process 总被引:2,自引:0,他引:2
Diarrhea caused by enterotoxigenic Escherichia coli (ETEC) is the main infectious disease of newborn calves. The first step of infection involves bacterial attachment to the
intestinal mucosa. This adhesion is mediated by fimbriae that recognize some glycoconjugates on the host cell surface, in
particular, several gangliosides. Because milk also contains gangliosides, these have been suggested to serve as ligands for
bacterial fimbriae and thus prevent the bacterial attachment to mucosa. The most relevant ETEC strains in calves, including
those with K99 and F41 fimbriae, were assayed to determine whether they are able to bind gangliosides isolated from several
stages of bovine lactation. Both GM3 and GD3, the main gangliosides of milk, were recognized by ETEC strains, although the
different fimbriae showed diverse levels of affinity. Unexpectedly, the adhesion to colostral gangliosides was considerably
weaker than that to gangliosides from the other stages of lactation. Because the carbohydrate moiety did not change and because
differences in the percentages of unsaturated FA and sphingosine between colostrum and other stages were observed, we conclude
that the differences in adhesion could be due to a different composition of the ganglioside caramide. 相似文献
77.
Depolymerization of the biopolymer chitosan by an autoclaving process at 121°C and 15 psi was investigated using various treatments. Acetic acid was found to be the most effective solvent in decreasing chitosan viscosity among the six organic acids tested. The rate of viscosity decrease increased with increasing chitosan concentration. The viscosity of 1% chitosan in 1% acetic acid decreased rapidly to 91% of the initial viscosity following the initial 15 min of autoclaving. This decreased gradually to 93% and 94% in 30 and 60 min, respectively, without being adversely affected by the chitosan solution volume. The degree of deacetylation was comparable before and after autoclaving for 60 min. Chitosan at three molecular weights (Mr = 1597, 1110, and 789 kDa) decreased in molecular weight by 46%–51% in the 15‐min treatment, 55%–60% in the 30‐min treatment, and 60%–62% in the 60‐min treatment. The addition of 0.1%–1.0% (v/v) concentrations of hydrogen peroxide to the chitosan solution autoclaved for 15 min decreased viscosity by 94%–98% and molecular weight by 69%–83%. This process is a simple, timesaving, homogeneous depolymerization procedure, and it is possible to prepare partially hydrolyzed chitosan with specified molecular weights by regulating the time of treatment. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1890–1894, 2003 相似文献
78.
Yang Gao Junya Iihama Daiki Hamana Ryo Iwasaki Sawao Honda Toru Asaka Munni Kumari Tomokatsu Hayakawa Samuel Bernard Philippe Thomas Yuji Iwamoto 《International Journal of Applied Ceramic Technology》2023,20(2):768-779
A series of β-SiAlON:Eu2+ phosphors were synthesized from single-source precursors, perhydropolysilazane chemically modified with Al(OCH(CH3)2)3, AlCl3, and EuCl2. The single-source precursors were converted to β-SiAlON:Eu2+ phosphors by pyrolysis under flowing N2 or NH3 at 1000°C, followed by heat treatment at 1800°C under an N2 gas pressure at 980 kPa. By varying the molar ratio of the chemical modifiers, β-SiAlON:Eu2+ with the compositions close to the theoretical ones expressed as Si6−zAlzOz−2yN8−z+2y:yEu2+ were synthesized, where the z values and Eu2+ contents were controlled in the ranges of .44–.78 and .35–1.48 mol%, respectively. The polymer-derived β-SiAlON:Eu2+ phosphors exhibited green emission under excitation at 460 nm attributed to the 4f7–4f6(7f3)5d1 transition of dopant Eu2+. High-angle annular dark-field-scanning transmission microscopy analysis confirmed that the doped-Eu2+ existed interstitially within the channels along the c axis of host β-SiAlON. Compared with the conventional powder metallurgy route, the polymer-derived ceramic route in this study offers some advantages in the grain growth of host β-SiAlON and photoluminescence properties in terms of green emission intensity under excitation at 460 nm, and the highest intensity was achieved for the polymer-derived β-SiAlON:Eu2+ with z = .64 and .37 mol% Eu2+. 相似文献
79.
Skim and whole milk powders were manufactured at lab scale by spray freeze drying (SFD), using liquid nitrogen as the cryogen. The polydispersity of droplet/particle sizes was limited using an encapsulator nozzle to atomize the feed. Particle morphology was examined using a scanning electron microscope. Samples were compared with equivalent spray-dried powders in tests of wettability and dissolution in water. The spray freeze-dried powders were found to be highly porous, with a uniform structure of pores throughout the entire particles. When tested in water, SFD skim milk powders wetted roughly three times as fast as industrially spray-dried agglomerated skim milk powders and were observed to dissolve rapidly by breaking down into smaller particles. 相似文献
80.
Mohammad G. Mohammad Masoud Hassanpour Vicky W. W. Tsai Hui Li Marc J. Ruitenberg David R. Booth Jordi Serrats Prue H. Hart Geoffrey P. Symonds Paul E. Sawchenko Samuel N. Breit David A. Brown 《International journal of molecular sciences》2013,14(1):547-562
Multiple sclerosis (MS) is a devastating neurological disease that predominantly affects young adults resulting in severe personal and economic impact. The majority of therapies for this disease were developed in, or are beneficial in experimental autoimmune encephalomyelitis (EAE), the animal model of MS. While known to target adaptive anti-CNS immune responses, they also target, the innate immune arm. This mini-review focuses on the role of dendritic cells (DCs), the professional antigen presenting cells of the innate immune system. The evidence for a role for DCs in the appropriate regulation of anti-CNS autoimmune responses and their role in MS disease susceptibility and possible therapeutic utility are discussed. Additionally, the current controversy regarding the evidence for the presence of functional DCs in the normal CNS is reviewed. Furthermore, the role of CNS DCs and potential routes of their intercourse between the CNS and cervical lymph nodes are considered. Finally, the future role that this nexus between the CNS and the cervical lymph nodes might play in site directed molecular and cellular therapy for MS is outlined. 相似文献