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51.
Dental calculus (DC) is a common deposit in periodontitis patients. We have previously shown that DC contains both microbial components and calcium phosphate crystals that induce an osteoclastogenic cytokine IL-1β via the NLRP3 inflammasome in macrophages. In this study, we examined the effects of cytokines produced by mouse macrophages stimulated with DC on osteoclastogenesis. The culture supernatants from wild-type (WT) mouse macrophages stimulated with DC accelerated osteoclastogenesis in RANKL-primed mouse bone marrow macrophages (BMMs), but inhibited osteoclastogenesis in RANKL-primed RAW-D cells. WT, but not NLRP3-deficient, mouse macrophages stimulated with DC produced IL-1β and IL-18 in a dose-dependent manner, indicating the NLRP3 inflammasome-dependent production of IL-1β and IL-18. Both WT and NLRP3-deficient mouse macrophages stimulated with DC produced IL-10, indicating the NLRP3 inflammasome-independent production of IL-10. Recombinant IL-1β accelerated osteoclastogenesis in both RANKL-primed BMMs and RAW-D cells, whereas recombinant IL-18 and IL-10 inhibited osteoclastogenesis. These results indicate that DC induces osteoclastogenic IL-1β in an NLRP3 inflammasome-dependent manner and anti-osteogenic IL-18 and IL-10 dependently and independently of the NLRP3 inflammasome, respectively. DC may promote alveolar bone resorption via IL-1β induction in periodontitis patients, but suppress resorption via IL-18 and IL-10 induction in some circumstances.  相似文献   
52.
Yellow, ripened (yellow with green tips) bananas were treated with nitrogen gas for 12, 24 and 48 h at 20 °C to study the effects of anaerobic conditions on the fruit quality, including the production of volatile compounds and activity of alcohol acetyltransferase (AAT) during the post‐harvest period. Significantly higher concentrations of acetaldehyde and ethanol were found in the treated fruit than in the untreated bananas after removal from the conditions. The 48‐h treatment showed higher levels of ethanol and acetaldehyde after storage. Immediately after releasing the fruit from the anaerobic atmosphere, the amounts of isobutyl acetate and isoamyl acetate decreased. The production of ethyl acetate increased markedly in each treatment unit 1 day after removing the fruit. Regardless of recovery from the production of isobutyl acetate and isoamyl acetate 1 day after treatment, the banana‐like aroma was denatured because of the production of high levels of ethyl acetate and ethanol. The increase in AAT was slightly lower in nitrogen‐treated fruit than untreated fruit. However, the activity in treated fruit was sufficient for ester production in bananas. The endogenous alcohol levels were increased during nitrogen gas treatment in the fruit due to the inhibition of ester production. Colour development of the bananas was greatly inhibited by the treatments, while the sugar content did not show any differences between the treated and untreated fruit. The results suggest that, even if bananas are removed from the short‐term anaerobic conditions, a loss in quality, except sweetness, easily occurs afterwards, especially the characteristic aroma of the fruit during the post‐harvest period. Copyright © 2006 Society of Chemical Industry  相似文献   
53.
Previously we reported that serum CA125 level is elevated in cases of pericardial effusion. We report three cases in which serum CA125 measurement is useful for assessing clinical status. In case 1, a 19-year-old came to our hospital for cardiac tamponade. Moderate degree of pericardial effusion and high CA125 level were observed. After the pericardectomy the serum CA125 level was normalized and pericardial effusion disappeared. Case 2, a 50-year-old man with mesothelioma and in whom serum CA125 level was elevated with pericardial effusion. After cardiac drainage his condition improved, with decreased CA125 level. However, later the CA125 level rose and recurrent localized pericardial effusion with worsening condition was observed. In case 3, in a 78-year-old woman with pericardial effusion no recurrence was observed after pericardial drainage. Her CA125 value was normal. These results indicated that measurement of CA125 value is a useful marker for assessing the clinical course of this disease.  相似文献   
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A new foam injection‐molding technology was developed to produce microcellular foams without using supercritical fluid (SCF) pump units. In this technology, physical blowing agents (PBA), such as nitrogen (N2) and carbon dioxide (CO2), do not need to be brought to their SCF state. PBAs are delivered directly from their gas cylinders into the molten polymer through an injector valve, which can be controlled by a specially designed screw configuration and operation sequence. The excess PBA is discharged from the molten polymer through a venting vessel. Alternatively, additional PBA is introduced through the venting vessel when the polymer is not saturated with PBA. The amount of gas delivered into the molten polymer is controlled by the gas dosing time of the injector valve, the secondary reducing pressure of the gas cylinder and the outlet (back) pressure of the venting vessel. Microcellular polypropylene foams were prepared using the developed foam injection‐molding technology with 2–6 MPa CO2 or 2–8 MPa N2. High expansion foams with an average cell size of less than 25 μm were prepared. The developed technology dispels arguments for the necessity to pressurize N2 or CO2 to the SCF to prepare microcellular foams. POLYM. ENG. SCI., 57:105–113, 2017. © 2016 Society of Plastics Engineers  相似文献   
56.
Petroleum pitches, coal-extract solutions and hydrogenated coal-extract solutions are co-carbonized with anthracene at 673 K. Chloroform-soluble fractions of the system are monitored by 1H n.m.r. for formation of 9.10 dihydroanthracene (DHA). A hydrogenated coal-extract solution is also co-carbonized at 673 K with anthracene together with thianthrene and sulphur. Ashland A240 petroleum pitch and anthracene are co-carbonized with hydrogenated anthracene oil and resultant 1H n.m.r. spectra are analysed for DHA. The pitches and coal-extract solutions are carbonized to 823 K and the optical textures of resultant cokes are assessed by optical microscopy. The purpose of the study is to assess if pitches which form cokes with larger optical textures or have greater abilities to modify the carbonization behaviour of coals also have the ability to act as ‘hydrogen shuttles’ in the carbonization system. Results would indicate that such pitches produce the largest amounts of DHA. It is proposed that the most efficient of the modifying pitches operate by extending the zone of temperature of maximum fluidity and by increasing the value of maximum fluidity by removal by proton transfer of radicals which if left in the carbonizing system would interact to form cokes of smaller optical texture.  相似文献   
57.
Catalytic activity and selectivity for hydrogenation of linoleic acid (cis-9,cis-12 18:2) were studied on Pt, Pd, Ru, and Ir supported on Al2O3. Stearic acid (18:0) and 10 different octadecenoic isomers (18:1) in the products could be separated completely by using a new capillary column coated by isocyanopropyl trisilphenylene siloxane for gas-liquid chromatography. The monoenoic acid isomers and dienoic acid isomers in the products on the various catalysts showed different distributions. The catalysts exhibited nearly equal selectivity for stearic acid formation. The 12-position double bond in linoleic acid has higher reactivity than the 9-position double bond in catalytic hydrogenation on platinum-group metal catalysts. In addition to hydrogenation products of linoleic acid, geometrical and positional dienoic acid isomers (trans-9,trans-12; trans-8,cis-12; cis-9,trans-13; trans-9,cis-13; cis-9,trans-12 18:2), due to isomerization of linoleic acid during hydrogenation, were contained in the reaction products. Ru/Al2O3 exhibited the highest activity for isomerization of linoleic acid with the noble metal catalysts. Conjugated octadecadienoic acid isomers have been observed in products of the reaction on Pt/Al2O3, Ru/Al2O3, and Ir/Al2O3. Catalytic activities of noble metals for positional and geometric isomerization of linoleic acid during hydrogenation decreased in the sequence of Ru ≥ Pt > Ir » Pd.  相似文献   
58.
The Sc3+ ion migration in the scandium tungstate solid was qualitatively demonstrated. For clarifying the exact migrant quantitatively, modified Tubandt electrolysis was performed for the Sc2(WO4)3 solid. As a result of the strict compensation, that is, vaporization and adherence compensations, a weight increase at the cathodic side and a weight decrease at the anodic side were reproducibly observed after the electrolysis. In addition, the Sc concentration at the cathodic side was increased and a corresponding decrease at the anodic side was observed. Therefore, the Sc3+ ion conduction in the Sc2(WO4)3 solid was quantitatively demonstrated.  相似文献   
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60.
A two‐phase duplex stainless steel was used as a model material in order to investigate the development of flow patterns when processing using high‐pressure torsion (HPT). The results show that double‐swirls are visible on the disc surfaces when processing with controlled amounts of anvil misalignment but not when the anvils are in an essentially perfect alignment. There are also shear vortices visible on the disc surfaces when processing with controlled amounts of misalignment but not when using perfect alignment. These results demonstrate the need for exercising significant care when processing discs by HPT. Prior to introducing torsional straining, it is important to ensure that the upper and lower anvils are in good alignment to within ≈25 µm.  相似文献   
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