Immunological Effects of Oenothein B,an Ellagitannin Dimer,on Dendritic Cells

Oenothein B is a unique macrocyclic ellagitannin dimer that has been found in various medicinal plants belonging to Onagraceae, Lythraceae, and Myrtaceae, with diverse biological activities. The immunological effects of tannins in terms of cytokine-release from macrophages and monocytes have been discussed, while the effects on other immunocompetent cells have been the subject of minimal investigation. We evaluated the immunomodulatory effects induced by tannin treatment in human dendritic cells (DCs), which play a critical role in the initial immune response, by measuring the changes in cytokine production, cell differentiation, and cell viability. Oenothein B showed significant down-regulation of the expression of cell surface molecules, CD1a and CD83, suggesting the inhibition of DC differentiation and/or maturation. The suppressive effect on DCs was associated with the induction of apoptosis without the activation of caspase-3/7, 8, and 9, and this was supported by the morphological features indicating significant nuclear condensation. Oenothein B also markedly suppressed the production of inflammatory cytokines, such as IL-1β and IL-6, in a dose-dependent manner. These data may, in part, be able to explain the traditional use of tannin-containing medicinal plants for the treatment of a variety of inflammatory diseases, including inflammatory bowel disease, celiac disease, and rheumatoid arthritis.     

Gaseous diffusion coefficients of methyl bromide and methyl iodide into air,nitrogen, and oxygen

The gaseous diffusion coefficients of methyl bromide (CH₃Br) and methyl iodide (CH₃I) into dry air, nitrogen, and oxygen have been measured in the temperature range 303–453 K and at atmospheric pressure via the Taylor dispersion method. Both for methyl bromide and methyl iodide, the diffusion coefficients do not vary in practice on substituting pure nitrogen or oxygen for dry air. The diffusion coefficients for methyl iodide are systematically smaller than those for methyl bromide by about 11%. For the methyl iodide‐oxygen system, the effect of the thermal decomposition of methyl iodide has been observed at 453 K. The present results can be reproduced well by the functional form D = AT^B, where D (cm²s^?1) is the diffusion coefficient at 101 325 Pa (1 atm) and T (K) is the absolute temperature. The constants A and B are as follows: methyl bromide‐(air, nitrogen, oxygen), A = 5.57 × 10^?6, B = 1.76; methyl iodide‐(air, nitrogen, oxygen), A = 5.26 × 10^?6, B = 1.75. © 2009 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20255     

HEAT TRANSFER IN A CONDUCTIVE-HEATING AGITATED DRYER

The heat transfers between the heating plane and the granular materials in both the “Stationary heating-plane type” and the “Moving heating-plane type” of the conductive-heating agitated dryers were discussed mainly from the view point of the scale-up of the dryer. Under the condition of complete mixing in the bed of bulk materials, the heat transfer models proposed for both the two types of dryers can predict the heat transfer coefficients in any sizes of the dryers. However, the complete mixing is not usually accomplished in the large scale of dryer. Hence, an “Incomplete mixing model” was proposed to estimate the effect of the incompleteness of mixing on the heat transfer coefficient. In this model, the incompleteness of mixing can be apparently taken into consideration only by increasing the contact time.     

Purification and characterization of a cytochrome P450 isozyme catalyzing lanosterol 14α-demethylation (P45014DM) in hamster liver

To characterize cholesterol synthesis in Syrian golden hamster, an isozyme of cytochrome P450, lanosterol 14α-demethylase (P45014DM), which catalyzes the initial step in the biosynthesis of cholesterol from lanosterol, was purified and its mode of induction by microsomal enzyme inducers was characterized. P450450DM was purified from hamster livers by chromatography using aminooctyl-Sepharose CL-4B, hydroxylapatite, DEAE-5PW, and CM-Sephrose CL-6B columns, to a specific content of 12.8 nmol/mg-protein. The purified protein displayed a single band on SDS-polyacrylamide gel electrophoresis with an apparent molecular weight of 52,000. The absorption spectra of the oxidized form of the purified protein howed a Soret peak at 417 nm in a low-spin state and a Soret peak of reduced CO-binding complex at 448 nm. In a reconstituted system, the purified protein catalyzed 14α-demethylation of 24,25-dihydrolanosterol (1.58 nmol/min/nmol-P450), although it did not show any activities toward testosterone and 7-ethoxyresorufin, marker substrates of other P450 families. Immunoblot analysis using an antibody against porcine P45014DM, which inhibited the activity of lanosterol 14α-demethylation in the hamster liver microsomes, demonstrated that the level of this isozyme protein was markedly decreased in dexamethasone-treated hamster livers. This was accompanied by a decrease in the enzyme activity. In contrast, the levels and the activity in the phenobarbital-and 3-methylcholanthrene-treated hamsters were almost equal to that in the untreated animals.     

Minority carrier controlled PEC solar cells, using n-Si electrodes modified with LB layers of ultrafine Pt particles

The open-circuit photovoltages (V_OC^S) of photoelectrochemical (PEC) solar cells, equipped with n-Si electrodes modified with ultrafine platinum (Pt) particles, have been investigated as functions of the Pt-particle density and the post-heat-treatment temperature. Langmuir-Blodgett layers of Pt-colloid particles stabilized by polyvinylpyrrolidone (PVP) are used to control the Pt-particle density on the n-Si electrodes. The ideality factor (n) and the dark saturation current density (j₀) are determined from plots of logarithm of the short-circuit photocurrent density versus V_OC. The n is unity for all the electrodes, independent of both the Pt density and the heat-treatment temperature, indicating that an ideal n-Si/solution junction is formed. The j₀ decreases and, hence, the V_OC increases as the Pt density decreases and also as the post-heat-treatment temperature is decreased. The decrease of j₀ is caused by the decrease in the majority carrier dark current density (j_0n). In cases where the Pt-modified n-Si electrodes are heat-treated at a low temperature of 150°C or not heat-treated, V_OC is in the range of 0.61 to 0.63 V, independent of the Pt density, indicating that minority carrier controlled solar cells are obtained.     

Heat transfer in an indirect-heat agitated dryerWärmeübertragung in indirekt beheizten Trommeltrocknern

The heat transfer coefficients between the heating plane and the granular material under agitation in a small indirect-heat agitated dryer with both moving and stationary heating planes were measured in order to obtain data for its design and to analyse the heat transfer mechanism. Based on the ‘particle heat transfer model’ suggested by Schlünder and partly revised by Mollekopf and Martin, heat transfer models for both types of heating planes were proposed to correlate the observed heat transfer coefficients. Comparison between the experimental and calculated heat transfer coefficients showed no serious deviation in either case. Using these models, it is possible to estimate the heat transfer coefficient between the heating plane and the granular material in this type of dryer.     

Synthesis of polyphosphazene random copolymers bearing alkoxyethoxy and trifluoroethoxy functional groups

The anionically initiated copolymerization of (CH₃OCH₂CH₂O)(CF₃CH₂O)₂ P=N-Si(CH₃)₃, (CH₃OCH₂CH₂OCH₂CH₂O)(CF₃CH₂O)₂ P=N-Si(CH₃)₃, (CH₃OCH₂CH₂O)₂ (CF₃CH₂O) P=N-Si(CH₃)₃, and (CH₃OCH₂CH₂OCH₂CH₂O)₂ (CF₃CH₂O) P=N-Si(CH₃)₃ with (CF₃CH₂O)₃ P=N-Si(CH₃)₃ is reported. These materials were characterized by³¹P and¹H NMR, SEC, and DSC.In situ ³¹P NMR studies indicate that monomers are simultaneously consumed, SEC traces show that these random copolymers exhibit monomodal distributions, and there is a gradient in solubilities as well as thermal and mechanical properties which is dependent upon the repeating unit ratios.     

The hysteresis phenomenon in flame lift-off on a bluff-body burner under airflow dominant conditions

We investigated the behavior of the lifted flame on a bluff-body burner under the airflow dominant condition by the higher annular airflow velocity and the lower central fuel jet one and found the appearance of the hysteresis phenomenon in lift-off height of the flame that depends on the history of the fuel jet velocity. The hysteresis behavior is entirely different from the case of the fuel flow dominant condition by the higher central fuel jet velocity and lower annular airflow one. The observation by shadowgraph revealed that the occurrence of the phenomenon has a relation to the interaction between the fuel jet and the recirculation airflow region on the burner.     

STRUCTURE FORMATION OF COATED FILMS WITH DISPERSED PIGMENTS DURING DRYING

ABSTRACT

In the drying of coated films with dispersed pigments, such as floppy disks, the structure of the film is formed during the drying process and depends on the drying condition. It is important to understand the structure formation during drying for the design of the dryer and die better quality of the product. We measured die drying characteristics of the film and determined the structure of dried film experimentally. A qualitative model for the structure formation during drying of the coated film is suggested.