Heterogeneous vascular patterns in renal cell carcinomas.

The present study proposes a classification of renal cancer tumor blood vessels according to their morphology and maturation grade. We identified four vascular patterns: reticular, diffuse, fasciculated and trabecular. The reticular pattern was present in 63% of cases, being characterized by the predominance of mature CD34+/SMAct+ tumor vessels, highly interconnected. For this pattern, 74% of cases had vascular invasion, and a significant correlation was observed between tumor grade and immature state of tumor vessels (p = 0.022). The diffuse pattern was observed in 23% of cases and was characterized by non-interconnected vessels predominantly of mature CD34+/SMAct+ type and vascular invasion in 64% of cases. Only 8% of cases, had a fasciculate model of vessels distribution, all of them being of mature type, located in the connective axis of papillary renal tumors. For this pattern vascular invasion was found in 50% of cases. In 6% of cases a trabecular pattern was observed and the lowest rate of vascular invasion was registered. We defined here four distinct vascular patterns in renal cell carcinomas showing a strong impact on vascular invasion. A complete morphological and molecular characterization of tumor vessels would be beneficial in elucidating the mechanisms that underlie the ineffectiveness of antiangiogenic/antitumor therapies.

Rovibrational Analysis of the nu(6) Bands of Four Symmetric Isotopomers of FClO(3).

High-resolution (ca. 5 x 10(-3) cm(-1)) infrared spectra of monoisotopic samples of F(35)Cl(16)O(3), F(37)Cl(16)O(3), F(35)Cl(18)O(3), and F(37)Cl(18)O(3) have been recorded in the region of the nu(6) fundamental band. This band is centered at 405.6055, 405.5097, 390.5406, and 390.4984 cm(-1), respectively. About 1000 nonzero-weighted transitions were fitted for each isotopomer with an isolated band model, obtaining a s.d. on the residuals close to the experimental precision. Three different reductions of the Hamiltonian have been tested and found almost equally good, although FClO(3) is a nearly spherical top molecule. Each includes the l(2, 2) interaction and either a d(t) DeltaK = +/-3 interaction term (reduction Q) an epsilon(t) DeltaK = +/-3 interaction term (reduction QD), or an l(2, -1) interaction (reduction D). Good agreement between the theoretical predictions for these reductions and the experimental data is observed. Copyright 1999 Academic Press.

The Interacting v6 = 2 Levels of D3Si35Cl: A Tool to Determine Ground State Constants from High-Resolution Spectra in the 440-590 and 900-1100 cm-1 Regions.

High-resolution FTIR spectra of monoisotopic D3Si35Cl have been recorded in the regions 440-590 cm-1 (nu3/nu6) and 900-1100 cm-1 (2nu6/nu3 + nu6/2nu3). A detailed rovibrational study was done for the 2nu06, 2nu-/+26, and 2nu3 overtone bands and for the 2nu+/-26-nu+/-16, 2nu06-nu-/+16, and (nu3 + nu+/-16)-nu+/-16 hot bands. For the first time the interactions occurring between the v6 = 2, v3 = v6 = 1, and v3 = 2 levels of any trideuterated silyl halide have been analyzed. The (nu3 + nu+/-16)-nu+/-16 hot band served to obtain accurate energies of the v3 = v6 = 1 level, the nu3 + nu6 combination band not being detectable on our spectra. The first experimental determination of A0 and D0K for this molecule was undertaken by a well-established method, using the nu6, 2nu+/-26-nu+/-16, and 2nu-/+26 bands. Ground state energy differences DeltaK(J) = E0(J, K) - E0(J, K - 3) were calculated for K values from 2 to 16. By a least-squares fit of 163 such differences, the A0 and D0K values thus obtained were (in cm-1): A0 = 1.4278230(8) and D0K = 5.3916(31) x 10(-6). Copyright 1999 Academic Press.

High-Resolution Study of the First Stretching Overtones of H3Si79Br.

The Fourier transform infrared spectrum of monoisotopic H3Si79Br (resolution 7.7 x 10(-3) cm-1) was studied from 4200 to 4520 cm-1, in the region of the first overtones of the Si-H stretching vibration. The investigation of the spectrum revealed the presence of two band systems, the first consisting of one parallel (nu0 = 4340.2002 cm-1) and one perpendicular (nu0 = 4342.1432 cm-1) strong component, and the second of one parallel (nu0 = 4405.789 cm-1) and one perpendicular (nu0 = 4416.233 cm-1) weak component. The rovibrational analysis shows strong local perturbations for both strong and weak systems. Seven hundred eighty-one nonzero-weighted transitions belonging to the strong system [the (200) manifold in the local mode picture] were fitted to a simple model involving a perpendicular component interacting by a weak Coriolis resonance with a parallel component. The most severely perturbed transitions (whose ||obs-calc || values exceeded 3 x 10(-3) cm-1) were given zero weights. The standard deviations of the fit were 1.0 x 10(-3) and 0.69 x 10(-3) cm-1 for the parallel and the perpendicular components, respectively. The weak band system, severely perturbed by many "dark" perturbers, was fitted to a model involving one parallel and one perpendicular band, connected by a Coriolis-type resonance. The K" . DeltaK = +10 to +18 subbands of the perpendicular component, which showed very high observed - calculated values ( approximately 0.5 cm-1), were excluded from this calculation. The standard deviations of the fit were 11 x 10(-3) and 13 x 10(-3) cm-1 for the parallel and the perpendicular components, respectively. Copyright 1998 Academic Press.