Keiji Kuwata

A multiple regression equation for prediction of posthepatectomy liver failure.

This article reports a multiple regression equation for prediction of posthepatectomy liver failure. In phase I, using the correlations between 17 preoperative parameters (Xi) and the postoperative course scored (Y) of the past 36 hepatectomized patients, we proposed the following multiple regression equation: Y = -110 + 0.942 X resection rate (%) + 1.36 X ICG retention rate (%) + 1.17 X patients age + 5.94 X ICG maximal removal rate (mg/kg/min). With the equation, the calculated Y value (prediction score) of these patients revealed that prediction scores of the eight nonsurvivors with liver failure were more than 50 points while those of the 28 survivors were 50 points or less. In phase II, the relationships between early prognosis and a precalculated prediction score were prospectively found the same as that seen in phase I. These findings indicate that our formula is a useful prognostic index for prediction of posthepatectomy liver failure.

Hemangioma of the liver. Diagnosis with combined use of laparoscopy and hepatic arteriography.

A case of hepatic hemangioma is reported in which preoperative diagnosis, with the combined aid of serial selective hepatic arteriography and laparoscopy, was necessary. The patient underwent right hepatic lobectomy after extensive extrahepatic individual ligations with no severe postoperative complications. The combined use of selective hepatic arteriography and laparoscopy is emphasized as essential for the correct diagnosis of hepatic hemangioma.

Initial distribution of vibration of the OH radicals produced in the H + O3 → OH(X2Π1/2,3/2) + O2 reaction. Chemiluminescence by a crossed beam technique

Abstract The chemiluminescence in the H + O 3 → OH(X 2 Π 1/2,3/2 ) + O 2 reaction was observed using a crossed beam technique. The initial population of the OH radicals in the vibrational state v (4 ⩽ v ⩽ 9) were found to be N (9) = 1.0, N (8) = 0.95 ± 0.1, N (7) = 0.9 ± 0.2, N (6) = 0.2 ± 0.1 and N (5) = N (4) = 0.2 ± 0.2. The total cross section of the formation of OH(4 ⩽ v ⩽ 9) was estimated to be of the order of 10 −2 nm 2 . No chemiluminescence was observed in the reaction D + O 3 → OD(X 2 Π 1/2,3/2 ) + O 2 under the present experimental conditions.

Electron spin relaxation of synthetic melanin and melanin-containing human tissues as studied by electron spin echo and electron spin resonance

Electron spin lattice relaxation times (T1) and the phase memory times (Tm) were obtained for the synthetic melanin system from 3-hydroxytyrosine (dopa) by means of electron spin echo spectroscopy at 77 degrees K. Saturation behavior of the ESR spectra of melanins in melanin-containing tissue and of the synthetic melanin was also determined at the same temperature. The spin lattice relaxation time and the spectral diffusion time of the synthetic melanin are very long (4.3 ms and 101 microseconds, respectively, in the solid state), and the ESR signal saturates readily at low microwave powers. On the other hand, ESR spectra of natural melanins from the tissues chosen for this study, as well as those of synthetic melanins which contain Fe3+ of g = 4.3 and Mn2+ of g = 2, are relatively difficult to saturate compared with samples without such metal ions. These results show clearly that a large part of those two metal ions in sites responsible for the ESR spectral components with these particular g values are coordinated to melanin in melanin-containing tissue, and modify the magnetic relaxation behavior of the melanin. Accumulations of these metal ions in melanins are different from system to system, and they increase in the order: hair (black), retina and choroid (brown), malignant melanoma of eye and skin, and lentigo and nevus of skin.

CIDEP of transient radical-ion pair: Photolysis of N,N,N′,N′-tetramethyl-p-phenylenediamine in 2-propanol

Abstract Anomalously spin-polarized solvated electrons produced by photoejection from N,N,N′,N′-tetramethyl- p -phenylenediamine in 2-propanol were detected by using a time-resolved ESR technique. The emission/absorption pattern of the CIDEP spectrum was observed immediately after laser excitation; thereafter it gradually changed to enhanced absorption. These two patterns may be attributable to the appearance of the exchange interaction in a radical-ion pair and the ordinary ST 0 mixing, respectively. These data lead to the conclusion that the sign of J is positive in this system.

Electron Spin Resonance of a γ‐Irradiated Single Crystal of a Hydrogen Peroxide—Urea Addition Compound at 77°K

The γ‐irradiated single crystal of an addition compound H2O2·CO(NH2)2 at 77°K exhibited ESR spectra which were attributed to an O2− ion radical and an HO2· free radical. The measurements were made at 9.21 and 22.4 kMc/sec for various orientations of the crystal in the magnetic field. For most orientations, the spectra of O2− and HO2· were singlet and doublet, respectively. An isotropic component of the doublet was approximately 11 G. The g values were found to be anisotropic with the principal values: g1=2.0886, g2=2.0084, and g3=2.0009 for O2−; while g1=2.0495, g2=2.0081, and g3=2.0018 for HO2·. There seems to be no report about O2− trapped in a molecular crystal so far, and the results were compared with O2− in ionic crystal.

Formation of an intense pulsed beam of CH3Cl in the ‖111≳ state using a 2‐m electrostatic hexapole field

An intense pulsed beam of CH3Cl in the ‖111≳ state without velocity selection was focused using a 2‐m electrostatic hexapole field. The beam intensity was estimated to be ∼1×1013 molecules pulse−1, which is much greater than the similar beams in the earlier study of Gandhi et al. by at least two orders of magnitude. The beam had a 3‐ms pulse width and was focused with an angular divergence of 0.7 mrad. The improvements in beam intensity and in the divergence of the beam can be mainly ascribable to the efficient pumping of the hexapole field through the cylindrical electrodes, which enables us to employ the helium seeding to have the fast stream velocity, the narrow distribution of velocity, and the aerodynamic effects. Those factors altogether made the velocity selection of the beam unnecessary.

Orientation-dependent CF3 emission observed in the Ar(3P) + CF3H → CF*3 (1E′, 2A″2) + H + Ar reaction

Abstract The orientation-dependent CF 3 emission in the visible region observed in the Ar( 3 P) + CF 3 H reaction was investigated. The Legendre polynomial and Engel-Levine function expansions were applied to obtain an orientational opacity function, in which the lowest six terms of the Legendre series were found to be important to reproduce the observed orientational dependence. In both cases, these opacity functions reveal three reactive sites. The most favorable one is the attack of the Ar( 3 P) atom at the CF 3 group in the collinear approach and the second one correlates with the direct approach to the F atom. The least favorable site is centered at around 140° in the region of H atom attack. There is a cone of small reactivity in the collinear direction at the H-end attack. Although the exchange interaction cannot completely explain the relative reactivity at each reaction site, the shape of the opacity function was attributed to the exchange interaction between the 6a 1 molecular orbital of CF 3 H and the 3p empty core orbital of Ar( 3 P).

Electron spin resonance of monomer and dimer cations of 1,4-, 1,5- and 1,8-dimethylnaphthalenes

The electron spin resonance spectra of the cations generated by the oxidation of 1,4-, 1,5- and 1,8-dimethylnaphthalenes have been observed. The 1,4 monomer cation changed to the dimer cation on lowering the temperature. The values of the hyperfine splitting constants in the 1,4 dimer cation differ considerably from one-half the values of those in the monomer. To account for the difference, two sandwich-type structures were assumed and Huckel molecular orbital calculations, which include the parameters to represent the feature of the dimer molecule, were carried out. Self-consistent field molecular orbital calculations have also been performed on the 1,4 dimer cation.

Orientation dependence of chemiluminescence spectra of CF3 formed in the reaction of oriented CF3H with Ar(3P)

Chemiluminescence of the CF*3 radical formed in the reaction of Ar(3P) with the oriented CF3H was taken at five different wavelengths in the range from 500 to 700 nm for two reactant orientations with a reference orientation. A remarkable alignment dependence of the emission spectra was observed. Analysis of the wavelength dependence of the CF3 chemiluminescence revealed the existence of three reactive sites due to two reaction mechanisms. One is preferable at the side-on orientation and the second is both at the CF3 end and H end orientations.