Analysis of Renal Cell Carcinoma as a First Step for Developing Mass Spectrometry-Based Diagnostics

Immediate diagnosis of human specimen is an essential prerequisites in medical routines. This study aimed to establish a novel cancer diagnostics system based on probe electrospray ionization-mass spectrometry (PESI-MS) combined with statistical data processing. PESI-MS uses a very fine acupuncture needle as a probe for sampling as well as for ionization. To demonstrate the applicability of PESI-MS for cancer diagnosis, we analyzed nine cases of clear cell renal cell carcinoma (ccRCC) by PESI-MS and processed the data by principal components analysis (PCA). Our system successfully delineated the differences in lipid composition between non-cancerous and cancerous regions. In this case, triacylglycerol (TAG) was reproducibly detected in the cancerous tissue of nine different individuals, the result being consistent with well-known profiles of ccRCC. Moreover, this system enabled us to detect the boundaries of cancerous regions based on the expression of TAG. These results strongly suggest that PESI-MS will be applicable to cancer diagnosis, especially when the number of data is augmented.     

Protonic conducting properties of sol-gel derived organic/inorganic nanocomposite membranes doped with acidic functional molecules

High temperature protonic conducting polymer membranes provide new technological applications in electrochemical devices including electrochromic displays, chemical sensors, fuel cells and others. Organic/inorganic nanocomposite membranes consisting of SiO₂/PEO (polyethylene oxides) hybrids are a remarkable family of isotropic, flexible, amorphous polymer materials, which have been synthesized through sol-gel processes. The hybrid membrane doped with acidic moieties such as monododecylphosphate or phosphotungstic acid shows good protonic conductivities at high temperatures above 100°C. The protonic conducting membrane was found to be thermally stable at high temperatures because of the inorganic SiO₂ framework in the nanocomposite matrix.     

Measurement of X-rays from muon to alpha sticking and fusion neutrons in solid/liquid D-T mixtures of high tritium concentration

We measured the yields of K-series X-rays from (αμ)⁺ ion formed by muon to alpha sticking as well as the yields and the disappearance rates of fusion neutrons in ³He-free solid and liquid D-T mixtures. The effective sticking probability ω_s obtained by neutron measurement is much smaller than any theoretical values so far published, while the discrepancy in αμ X-ray yield seems less significant. This revised version was published online in August 2006 with corrections to the Cover Date.     

Mixing of triply degenerated molecular orbitals in C602− and C603−

Mixing of triply degenerated lowest unoccupied molecular orbitals (LUMO; t_1u) and the next LUMO (NLUMO; t_1g) of a neutral C₆₀ molecule was estimated when it becomes dianionic (C₆₀²⁻) and trianionic (C₆₀³⁻) species. The electronic structure of the basic C₆₀ was obtained by a semiempirical (INDO type) Hartree-Fock scheme and the mixing of the t_1u and t_1g MOs by the conventional configuration interaction (CI) method assuming I_h structural symmetry of a C₆₀ for the sake of simplicity. The most favorable electronic states of C₆₀²⁻ and C₆₀³⁻ are predicted to be triplet and doublet, respectively. Furthermore, in C₆₀²⁻, the energy difference of this triplet state and the first excited singlet state is very close, which agrees well with the experimental observation. © 1997 John Wiley & Sons, Inc.     

Permselectivity between two anions in anion exchange membranes crosslinked with various diamines in electrodialysis

A membranous copolymer crosslinked with divinylbenzene reacted with N,N,N′,N′-tetra-methylethylenediamine, N,N,N′,N′-tetramethyl-1,3-propanediamine, and N,N,N′,N′-tetramethyl-1,6-hexanediamine to prepare highly crosslinked anion exchange membranes. More than 80% of both tertiary amino groups of the diamines reacted with chloromethyl groups of the membrane to form crosslinkage. After formation of the high crosslinkage of the membrane was confirmed with dialysis of a neutral molecule, electrochemical properties of the obtained membranes (mainly, relative transport number between two anions in electrodialysis) were evaluated: nitrate ions to chloride ions, sulfate ions to chloride ions, fluoride ions to chloride ions, and bromide ions to chloride ions. Though larger anions, in general, were difficult to permeate through the membranes due to high crosslinkage, the number of methylene groups of the diamines (which means the increase in hydrophobicity of anion exchange groups) also affected the relative transport number between two anions. The lower the hydration of anions, the higher the relative transport number of the anions through the membranes with the hydrophobic anion exchange groups. © 1996 John Wiley & Sons, Inc.     

Improved recovery of trace amounts of gold (III), palladium (II) and platinum (IV) from large amounts of associated base metals using anion-exchange resins

The adsorption and desorption behaviors of gold (III), palladium (II) and platinum (IV) were surveyed in column chromatographic systems consisting of one of the conventional anion-exchange resins of large ion-exchange capacity and dilute thiourea solutions. The noble metals were strongly adsorbed on the anion-exchange resins from dilute hydrochloric acid, while most base metals did not show any marked adsorbability. These facts made it possible to separate the noble metals from a large quantity of base metals such as Ag (I), Al (III), Co (II), Cu (II), ¶Fe (III), Mn (II), Ni (II), Pb (II), and Zn (II). Although it used to be very difficult to desorb the noble metals from the resins used, the difficulty was easily overcome by use of dilute thiourea solutions as an eluant. In the present study, as little as 1.00 μg of the respective noble metals was quantitatively separated and recovered from as much as ca. 10 mg of a number of metals on a small column by elution with a small amount of dilute thiourea solution. The present systems should be applicable to the separation, concentration and recovery of traces of the noble metals from a number of base metals coexisting in a more extended range of amounts and ratios.     

Synthesis and applications of porous spg (shirasu porous glass) microspheres

Fairly uniform porous microspheres of poly(styrene) (PS) and poly(methyl methacrylate) (PMMA) were synthesized using a particular microporous glass membrane (SPG). Average diameters of these spheres are from 2.5 to 38 μm with the coefficient of variation (CV) around 10%. A maximum specific surface area of 370 m² /g was achieved. Uniform dispersion of MMA droplets was successfully prepared only when the swelling process reported by Higuchi and Misra was adopted. Two potential applications, one as a packing material for column chromatography, and the other as a carrier of enzyme immobilization, were demonstrated.