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Nuclear structure and decay data pertaining to all nuclides with mass number A=92 (As, Se, Br, Kr, Rb, Sr, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd) have been compiled and evaluated, and incorporated into the ENSDF data file. A l l l i t e r a t u r e a v a i l a b l e b y 1 5 S e p t e m b e r 2 0 1 2 h a s b e e n c o n s i d e r e d . T h i s e v a l u a t i o n s u p e r s e d e s t h e p r e v i o u s p u b l i c a t i o n f o r t h i s m a s s c h a i n ( C o r a l M . B a g l i n , N u c l e a r D a t a S h e e t s 9 1 , 4 2 3 ( 2 0 0 0 ) ( N o v e m b e r 2 0 0 0 c u t o f f date)), and subsequent unpublished reevaluations by C.M. Baglin for 9 2 Kr (January 2004 literature cut-off) and 92 Sr (August 2003 literature cut-off).Acknowledgments: The evaluator thanks the reviewer of this manuscript for constructive comments. The evaluator

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The effect of solute paramagnetic ions on the longitudinal magnetic relaxation rate 1/T1 of solvent water protons depends on magnetic field strength and on the chemical environment of the ions. The variation of 1/T1 with field has been measured for solutions of Gd3+ and Mn2+ ions in three grossly different environments near physiological pH: the hydrated aquoion; chelated by EDTA (ethylenediaminetetraacetic acid) and DTPA (diethylenetriaminepentaacetic acid); and bound to the protein concanavalin A. It is demonstrated that over the field range at which NMR imaging is currently being done, the chemical environment can alter 1/T1 of solvent protons by more than an order of magnitude. The relevance of these results to the potential utility of these ions as agents for enhancement of contrast in NMR images is discussed.

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Mn(III), Fe(III), and Gd(III) complexes of tetrakis(4-sulfonatophenyl)porphyrin (TPPS) and several other porphyrins were evaluated as potential MRI contrast agents. Based on consideration of relaxivity and stability properties in solution, MnTPPS was found to be the compound of choice. At pH 7 the Gd and Mn complexes significantly enhanced the water proton relaxation rate, while the relaxivity of FeTPPS exhibited a significant loss of relaxivity above pH 6 due to oxy-dimer formation. Although GdTPPS exhibited the highest relaxivity in solution, this property was rapidly lost due to dissociation of the metal ion. By contrast MnTPPS remained stable in human plasma after incubation for 9 days. Upon intravenous injection into athymic mice bearing subcutaneous human colon carcinoma xenografts, MnTPPS provided enhanced relaxation of the tissue water in several excised mouse tissues, notably kidney, liver, and tumor. The results at a fixed field (0.25 T) and relaxation dispersion studies showed decreases in water relaxation rates with time for kidney and liver, but an increase for the tumor, with a maximum near 4 days at the highest dose used.

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