Molecular Hydrogen Enhances Proliferation of Cancer Cells That Exhibit Potent Mitochondrial Unfolded Protein Response

Molecular hydrogen ameliorates pathological states in a variety of human diseases, animal models, and cell models, but the effects of hydrogen on cancer have been rarely reported. In addition, the molecular mechanisms underlying the effects of hydrogen remain mostly unelucidated. We found that hydrogen enhances proliferation of four out of seven human cancer cell lines (the responders). The proliferation-promoting effects were not correlated with basal levels of cellular reactive oxygen species. Expression profiling of the seven cells showed that the responders have higher gene expression of mitochondrial electron transport chain (ETC) molecules than the non-responders. In addition, the responders have higher mitochondrial mass, higher mitochondrial superoxide, higher mitochondrial membrane potential, and higher mitochondrial spare respiratory capacity than the non-responders. In the responders, hydrogen provoked mitochondrial unfolded protein response (mtUPR). Suppression of cell proliferation by rotenone, an inhibitor of mitochondrial ETC complex I, was rescued by hydrogen in the responders. Hydrogen triggers mtUPR and induces cell proliferation in cancer cells that have high basal and spare mitochondrial ETC activities.     

Equilibrium of one-pot polymerization of polyimide

One-pot polymerization of polyimide from 3,3′,4,4′-biphenyl tetracarboxylic dianhydride (BPDA) and 4,4′-oxydianiline (ODA) was examined. The equilibrium in the polyimide with water was examined in detail in p-chlorophenol solution during the polymerization. The equilibrium constant was expressed by log K = 1.50 + 1433 (1/T). The polymerization reaction is exothermic. The molecular weight increased with decrease of temperature. © 1996 John Wiley & Sons, Inc.     

Effect of chitosan feeding on intestinal bile acid metabolism in rats

The effect of chitosan feeding (for 21 days) on intestinal bile acids was studied in male rats. Serum cholesterol levels in rats fed a commercial diet low in cholesterol were decreased by chitosan supplementation. Chitosan inhibited the transformation of cholesterol to coprostanol without causing a qualitative change in fecal excretion of these neutral sterols. Increased fiber consumption did not increase fecal excretion of bile acids, but caused a marked change in fecal bile acid composition. Litcholic acid increased sigificantly, deoxycholic acid increased to a leasser extent, whereas hyodeoxycholic acid and the 6β-isomer and 5-epimeric 3α-hydroxy-6-keto-cholanoic acid(s) decreased. The pH in the cecum and colon became elevated by chitosan feeding which affected the conversion of primary bile acids to secondary bile acids in the large intestine. In the cecum, chitosan feeding increased the concentration of α-,β-, and ω-muricholic acids, and lithocholic acid. However, the levels of hyodeoxycholic acid and its 6β-isomer, of monohydroxy-monoketo-cholanoic acids, and of 3α, 6ξ, 7ξ-trihydroxy-cholanoic acid decreased. The data suggest that chitosan feeding affects the metabolism of intestinal bile acids in rats.     

Stabilization effect of Co for Mo phase in CoMoAl2O3 hydrodesulfurization catalysts studied with X-Ray photoelectron spectroscopy

The promotional effects of Co in $\text{CoMo}\text{Al}{}_2\text{O}{}_3$ hydrodesulfurization (HDS) catalysts were studied by means of X-ray photoelectron spectroscopy. The higher MoO₃-content $\text{Mo}\text{Al}{}_2\text{O}{}_3$ catalysts (10 and 20 wt% MoO₃) contain mobile Mo, which migrates from the pores to the outermost surface layers of the catalysts and segregates to form less active crystalline MoS₂ during the HDS reaction, while in the case of $\text{Mo}\text{Al}{}_2\text{O}{}_3$ (5 wt% MoO₃) catalyst: no migration of Mo was observed. It is revealed that the Co in $\text{CoMo}\text{Al}{}_2\text{O}{}_3$ catalyst inhibits the migration and segregation of Mo and that it keeps Mo effective for the HDS reaction, since no surface enrichment of Mo was observed. It is concluded that stabilization of the Mo monomolecular layer is the main role of Co. The active species of Mo is suggested to have the composition of S/Mo(IV) = 1 on the basis of the sulfur contents of the catalysts under the mild HDS reaction conditions.     

Ozonization of amides

Ozonization of various amides was carried out as a model reaction for the degradation of polyamides with ozone. N-alkylamides and N,N-dialkylamides were found to be reactive compared with those amides which have no alkyl group on the nitrogen atom, and it was suggested that ozone attacks preferentially N-methylene or N-methyl group of amides in the first step of ozonization.     

Observation of single-walled carbon nanotubes by photoemission microscopy

Single-walled carbon nanotube networks grown on SiO₂ pillars were studied by means of scanning photoemission microscopy. The individual nanotubes or nanotube bundles growing from the pillar tops were observed in C 1s images. Band bending near catalytic Fe/nanotube contacts in an end-bonded configuration was studied by measuring C 1s spectra along the tube axes. Within our experimental resolution, no band bending was observed. This implies that the depletion width is less than the spatial resolution of the scanning photoemission microscope (90 nm) or that the amount of the band bending is less than 0.1 eV.     

Improvement of Selectivity for Partial Hydrogenation of Benzene by Rare Earth Nitride Upon NH3 Treatment

For the liquid-phase partial hydrogenation of benzene at 483 K, the selectivity toward cyclohexene was greatly improved upon treating rare earth nitride with ammonia. For YbN obtained by thermal decomposition of Yb(NH₂)₂ at 1173 K, the selectivity of the NH₃-treated YbN was 75%, in contrast to nil for the untreated YbN.     

Encapsulation-release property of amphiphilic hyperbranched d-glucan as a unimolecular reverse micelle

The synthesis of a novel unimolecular reverse micelle, the hyperbranched d-glucan carbamate (3), was accomplished through the carbamation reaction of the hyperbranched d-glucan (1) with the N-carbonyl l-leucine ethyl ester (2) in pyridine at 100 °C. Polymer 3 was soluble in a large variety of organic solvents, such as methanol, acetone, chloroform, and ethyl acetate, and insoluble in water, which remarkably differed from the solubility of 1. The degree of carbamate substitution (DS) for 3 was controlled by the feed rate of 2, and the DS values were in the range of 46.0-93.7%. Polymer 3 possessed the encapsulation ability for water-soluble molecules, such as rose bengal, thymol blue, and alizarin yellow in chloroform, and the encapsulation ability depended on the hydrophilicity of 3 and the molecular size of the dye. The rose bengal (RB) encapsulated polymer (RB/3) showed a slow release from the RB/3 system into water at neutral pH, while the release rate was significantly accelerated by the hydrolysis of the hydrophobic polymer shell under basic conditions.