ABO antigen expression in graft tissue: is titration against donor erythrocytes relevant?

ABO-incompatible living donor renal transplantation has become an accepted treatment for end-stage renal disease. Two main factors appear to be important when crossing the ABO barrier, the donor organ A/B antigen expression and the amount of recipient anti-A/B antibody. Antigen expression depends on the ABO blood group and subgroup and may vary in different tissues and cells.

Successful ABO-incompatible liver transplantation using A2 donors.

Introduction: The longer waiting time for a liver graft among patients with blood group O makes it necessary to expand the donor pool for these patients. We herein have reported our experience with ABO-incompatible liver transplantation using A(2) donors to blood group O recipients.

Patients And Methods: Between 1996 to 2005, 10 adult blood group O recipients received 10 A(2) cadaveric grafts.

Adult ABO-incompatible liver transplantation, using A and B donors.

Background: The longer waiting time for a liver graft in patients with blood group O makes it necessary to expand the donor pool for these patients. This applies in both urgent situations and for elective patients. We report on our experience with ABO-incompatible liver transplantation using A2 and B non-secretor donors here.

Ischemic preconditioning can overcome the effect of moderate to severe cold ischemia on concordant mouse xeno-heart transplants.

Purpose: Concordant mouse xeno-heart transplants are relatively sensitive to ischemia-reperfusion injury. We investigated the effect of an ischemic preconditioning (IPC) protocol on the functional and biochemical outcome of mouse xenohearts transplanted to the Lewis rat.

Material And Methods: NMRI mice (30 to 40 g) were anesthetized, intubated, and mechanically ventilated.

Singlet oxygen energy illumination during moderate cold ischemia prolongs the survival of concordant hamster xeno-heart transplants.

Introduction: Singlet oxygen energy (SOE) is a potent inhibitor of reactive oxygen species (ROS) in vitro and in vivo in certain dose ranges and can improve the levels of high-energy phosphates (HEP) in concordant hamster xeno-heart transplants. Some data indicate that a certain degree of cold ischemia (CI) might be beneficial to xenotransplants. We investigated if SOE illumination of hamster xeno-hearts during moderate cold ischemia (CI) improved graft survival.

Characterization of a chiral stationary phase by HR/MAS NMR spectroscopy and investigation of enantioselective interaction with chiral ligates by transferred NOE.

The surface chemistry of a chiral stationary phase (CSP) with a (tert-butyl carbamoyl) quinine selector immobilized on thiol-modified silica has been characterized by (1)H HR/MAS NMR and (29)Si CP/MAS NMR spectroscopy. The mostly well-resolved (1)H signals could be assigned to stem from the surface-bound selector and the latter suggested a bi- and trifunctional silane linkage. Suspended-state NMR spectroscopy thus proved a well-characterized surface chemistry as proposed.

Comparisons of the interactions between two analytes and two structurally similar chiral stationary phases using high-performance liquid chromatography, suspended-state high-resolution magic angle spinning nuclear magnetic resonance and solid-state nuclear magnetic resonance spectroscopy.

A study of the retention behaviour of the enantiomers (R)- and (S)-1,1'-binaphthyl-2,2'-diol as well as (+) and t-)-O,O'-dibenzoyl-tartaric acid was performed using the two chiral stationary phases (CSPs) Kromasil-DMB and Kromasil-TBB. Detailed information about the interactions between the analytes and the two CSPs was obtained from suspended-state HR/MAS transferred NOESY NMR experiments as well as suspended-state HR/MAS 1H NMR titration experiments. Good correlation between the suspended-state HR/MAS NMR experiments and the corresponding HPLC experiments was obtained.

Determination of enantiomer separation factors by nuclear magnetic resonance spectroscopy and by chiral liquid chromatography.

The equilibrium constants K+ and K- for formation of the diastereomeric complexes of the two enantiomers of O,O'-dibenzoyltartaric acid (DBTA) with the chiral selector N,N'-diallyltartardiamide bis-(4-tert.-butylbenzoate) (TBB) have been determined by 1H-NMR. The experiments were performed at different temperatures in CDCl3 or in cyclohexane-d12/2-propanol-d8 mixtures.

Solvent-dependent enantioselective interaction of some bis-allylamide chiral selectors studied by NMR.

A series of chiral selectors, all of them bis-allylamides of C(2)-symmetric dicarboxylic acids, were studied by NMR in different solvents in an attempt to affect the equilibria between free selector and the diastereomeric complexes formed by its interaction with the (+)- and (-)-forms of O,O'-dibenzoyltartaric acid (DBTA). The results show that by changing the polarity of the solvent the equilibria are displaced, as observed from changing chemical shift differences. Phase-sensitive (1)H[(1)H]-NOESY experiments revealed different interactions between the chiral selector and the analyte enantiomers.

A new chiral selector based on trans-acenaphthen-1,2-dicarboxylic acid.

The chiral selectors (R,R)- and (S,S)-trans-acenaphthen-1,2-dicarboxylic acid bis-allylamide have been synthesized and characterized. The route to the selectors involved synthesis of the trans-dicarboxylic acid via sodiation and carbonation of acenaphthylene, followed by reaction of the bis-acid chloride with allylamine. The racemic bis-allylamide derivative was resolved into its enantiomers by preparative liquid chromatography.