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Interstitial fibrosis and tubular atrophy (IFTA) is found in approximately 25% of 1‐year biopsies posttransplant. It is known that IFTAcorrelates with decreased graft survival when histological evidence of inflammation is present. Identifying the mechanistic etiology of IFTAis important to understanding why long‐term graft survival has not changed as expected despite improved immunosuppression and dramatically reduced rates of clinical acute rejection (AR) (Services UDoHaH. http://www.ustransplant.org/annual_reports/current/509a_ki.htm). Gene expression profiles of 234 graft biopsy samples were obtained with matching clinical and outcome data. Eighty‐one IFTAbiopsies were divided into subphenotypes by degree of histological inflammation: IFTAwith AR,IFTAwith inflammation, and IFTAwithout inflammation. Samples with AR(n = 54) and normally functioning transplants (TX; n = 99) were used in comparisons. A novel analysis using gene coexpression networks revealed that all IFTAphenotypes were strongly enriched for dysregulated gene pathways and these were shared with the biopsy profiles of AR, including IFTAsamples without histological evidence of inflammation. Thus, by molecular profiling we demonstrate that most IFTAsamples have ongoing immune‐mediated injury or chronic rejection that is more sensitively detected by gene expression profiling. These molecular biopsy profiles correlated with future graft loss in IFTAsamples without inflammation. In this multicenter study featuring gene expression profiles with matching demographic and long‐term follow‐ up data, the authors demonstrate that biopsies with interstitial fibrosis and tubular atrophy without alternative explanations for pathogenesis and regardless of histological reads with or without inflammation, have significantly worse graft survival than those with biopsy‐proven normal transplant histology and differential gene expression changes that indicate ongoing cellular immune‐mediated injury that correlate with worse long‐term outcomes. See Maluf et al's editorial on page 1947.

Interstitial fibrosis and tubular atrophy (IFTA) is found in approximately 25% of 1‐year biopsies posttransplant. It is known that IFTA correlates with decreased graft survival when histological evidence of inflammation is present. Identifying the mechanistic etiology of IFTA is important to understanding why long‐term graft survival has not changed as expected despite improved immunosuppression and dramatically reduced rates of clinical acute rejection (AR) (Services UDoHaH. http://www.ustransplant.org/annual_reports/current/509a_ki.htm). Gene expression profiles of 234 graft biopsy samples were obtained with matching clinical and outcome data. Eighty‐one IFTA biopsies were divided into subphenotypes by degree of histological inflammation: IFTA with AR, IFTA with inflammation, and IFTA without inflammation. Samples with AR (n = 54) and normally functioning transplants (TX; n = 99) were used in comparisons. A novel analysis using gene coexpression networks revealed that all IFTA phenotypes were strongly enriched for dysregulated gene pathways and these were shared with the biopsy profiles of AR, including IFTA samples without histological evidence of inflammation. Thus, by molecular profiling we demonstrate that most IFTA samples have ongoing immune‐mediated injury or chronic rejection that is more sensitively detected by gene expression profiling. These molecular biopsy profiles correlated with future graft loss in IFTA samples without inflammation.

Rhodium nanoparticles were prepared by homogeneous nucleation in aqueous polymer solution and by heterogeneous nucleation on the interlayer space of layered montmorillonite and kaolinite minerals by reduction with NaBH4 in aquatic dispersion. Rhodium particles were stabilized by polymers and by the lamellae of layered silicates. The effect of the molecular mass and the concentration of polymers on the size of the particles formed was studied using neutral polyvinylpyrrolidone, cationic poly(diallyldimethylammonium chloride), and anionic poly(sodium 4-styrenesulfonate). The effect of the concentration of the rhodium precursor was also examined; reduction of rhodium ions was controlled by X-ray photoelectron spectroscopy. Interlamellar incorporation of nanoparticles was monitored by X-ray diffraction and small-angle X-ray scattering verified by transmission electron microscopy. Average particle size fell within the range of 1−3 nm, depending on the stabilization method used and the concentration of precursor rhodium ions.

Abstract: Pd nanoparticles were synthesized by reduction of palladium acetate by ethanol in systems containing tetrahydrofuran (THF) as dispersion medium and tetradodecylammonium bromide (TDABr) surfactant as stabilizer. The polar phase (ethanol) acts at the same time as reducing agent. THF/TDABr/H2O inverse microemulsions containing micelles of various sizes were also prepared, and the structure of complex liquids was studied by density measurements. Sols containing nanosize Pd0 particles were synthesized within the water droplets of this micellar system. The stabilized Pd0/surfactant system was characterized by density measurements, absorption spectroscopy, and transmission electron microscopy. The stabilizing surfactant layer adsorbed on the liquid/liquid interface and on the surface of the nanoparticles (i.e., the liquid/solid interface) significantly reduced the excess volume for the palladium nanodispersion in organic solvent.

The coordinatively unsaturated intermediates prepared by thermal decomposition of the phosphonium hydrogen cyanocobaltates were investigated by magnetic methods, IR and visible spectroscopy. Their reactions with amines and phosphines yield novel preparable species.

The derivatives of cyano complex compounds of iron, cobalt and manganese with the triphenylphosphonium-cation were prepared and investigated by IR- andMössbauer-spectroscopic methods. The thermal decomposition of the triphenylphosphonium-cyanometallates leads to intermediates which can be isolated.

Ten proteins that exhibit long-lived phosphorescence lifetimes at room temperature were examined for sensitivity to quenching by molecules that are external to the protein. The bimolecular quenching rate constant was found to decrease exponentially with the distance of the tryptophan from the protein surface. Theoretical analysis shows that this behavior is expected for an electron-exchange reaction between the buried tryptophan and quenchers in solution in the rapid diffusion limit. The results allow evaluation of the distance parameter, ρ, for electron transfer through the general protein matrix at 1.0 A, For a unimolecular donor-acceptor pair with ket = ko exp(-r/ρ), ko = 109sec-1.

Nine iron(II) ethylene glycol sulphate complexes were prepared. Their compositions were determined by standard analytical methods. They were characterized by means of temperature-dependent magnetic susceptibility and Mössbauer spectroscopic measurements. On the basis of the patterns of their thermal decompositions, the complexes could be classified into three groups.

Measurements of the Doppler effect of the annihilation ?-line and of the positron lifetime were carried out in three series of solid coordination complexes; the Mössbauer spectra of the iron-containing samples were also recorded. The lack of correlation between the Móssbauer and positron annihilation parameters suggests that electrons of the ligands rather than those of the central atoms dominate in positron annihilation processes.

The irreversible effects of pressure (1-2000 atm) upon the enzymatic activity and structure of the Ca2+-ATPase of sarcoplasmic reticulum were investigated. Sarcoplasmic reticulum vesicles suspended in a medium of 0.1 M KCl, 10 mM imidazole, pH 7.0, 5 mM MgCl2, and 0.5 mM EGTA irreversibly lose their Ca2+ transport and Ca2+-stimulated ATPase activities on exposure to pressures of 800-2000 atmospheres. The pressure-induced inactivation of Ca2+-ATPase is accompanied by inhibition of the formation of phosphorylated enzyme intermediate, an increase in the passive Ca2+ permeability of the membrane, and structural changes in the Ca2+-ATPase as shown by disruption of Ca2+-ATPase membrane crystals, increased susceptibility to tryptic digestion, unmasking of SH groups, and loss of the conformational responses to Ca2+ and vanadate. The sensitivity to pressure is influenced by enzyme conformation. Ca2+ or vanadate + EGTA protect the Ca2+-ATPase against pressure-induced inactivation, implying a greater stability of the enzyme in the E1 and E2 states than in the conformational equilibrium that prevails at low [Ca2+] in the absence of vanadate. Protection against pressure inactivation was also observed in the presence of sucrose, glycerol, ethylene glycol and 1 M KCl, suggesting that water density modifying groups significantly affect the stability of Ca2+-ATPase under pressure.

Ten proteins that span a wide range of phosphorescence lifetimes were examined for sensitivity to quenching by four agents of disparate chemical nature. The results show that quenching efficiency is relatively independent of the quencher and is highly correlated with depth of burial of the phosphorescent tryptophan. The bimolecular quenching rate constants (kq) measured for the different proteins, spanning 5 orders of magnitude in kq, are found to decrease exponentially with the distance (r) of the tryptophan in angstroms from the protein surface--i.e., kq = Aexp(-r/rho), where A contains a geometrical factor dependent on tryptophan burial and surface geometry [corrected]. Theoretical analysis shows that this behavior can be expected for an electron-exchange reaction between the buried tryptophans and quenchers in solution in the rapid diffusion limit. Therefore, the results obtained provide evidence for an exponential dependence of electron-transfer rate on distance in a protein environment and evaluate the distance parameter, rho, for electron transfer through the general protein matrix at 1.0 A. For a unimolecular donor-acceptor pair with ket = koexp(-r/rho), ko approximately 10(9) sec-1.

Trypsin cleaves the Ca2+-ATPase of sarcoplasmic reticulum into two major fragments (A and B), followed by subsequent cleavage into smaller peptides. Although the ATP-dependent Ca2+ transport is still observed after cleavage of the ATPase into the A and B fragments, the Ca2+ transport energized by acetyl phosphate is strongly inhibited. Covalent labeling of the Ca2+-ATPase by fluorescein 5'-isothiocyanate inhibited both the ATP and acetyl phosphate-dependent Ca2+ transport. Vanadate protected the A and B fragments from further hydrolysis and preserved the ability of the cleaved Ca2+-ATPase to form crystals and to show the characteristic conformational changes in response to Ca2+ and EGTA that are observed with the intact enzyme. The protective effect of vanadate may be useful for the isolation of the A and B fragments in functional form.

The derivatives of cyano complex compounds of iron, cobalt and nickel with bifunctional phosphonium-cations were prepared and investigated. In the case of iron and cobalt the phosphonium—hydrogen derivatives can be produced too beside those of the phosphonium-complexes. The thermal decomposition of the compounds was examined by the derivatographic method. The ?CN and ?NO stretching frequencies of the complexes were compared with the similar frequencies in those of the alkaline cyano complexes and their corresponding free acids. The thermal decomposition of phosphonium—hydrogen—cyanometallates leads to coordinatively unsaturated intermediates which can be prepared.

Nanocrystalline multilayer thin film coatings, composed of nanometer-scale thick CrN, TiAlN and MoS2 tri-layer systems, were prepared by reactive co-sputtering processes. The self-lubricated multilayer coating structures were deposited by one-fold oscillating movement of substrates in front of the sputter sources. Three independently operated direct current (dc) excited unbalanced magnetrons (UM) with rectangular cathodes of TiAl alloy (50/50%), pure chromium and MoS2 were used as sputter sources. The reactive sputtering process was performed in a mixture of Ar-N2 atmosphere. Hardened high-speed-steel (HSS) and thin oxide covered Si (100) wafers were used as substrates for tribological- and microstructure investigations, respectively. According to results of the chemical composition evaluated by Auger-electron spectroscopy (AES) and microstructure investigation by cross sectional transmission electron microscopy (XTEM), the CrN, TiAlN and the MoS2 phases form practically continuous layers with large gradient transition of composition. The as-deposited CrN/ (Al,Ti)N/MoS2 coatings have shown good friction behaviour, tested at room temperature in dry sliding condition with a ball-on-disk tribometer.