Psychological rejection of the transplanted organ and graft dysfunction in kidney transplant patients

Melinda Látos,1 György Lázár,1 Zoltán Horváth,1 Victoria Wittmann,1 Edit Szederkényi,1 Zoltán Hódi,1 Pál Szenohradszky,1 Márta Csabai2 1Department of Surgery, Faculty of Medicine, 2Psychology Institute, University of Szeged, Szeged, Hungary Abstract: Interdisciplinary studies suggest that the mental representations of the transplanted organ may have a significant effect on the healing process. The objective of this study was to examine the representations of the transplanted organ and their relationship with emotional and mood factors, illness perceptions, and the functioning of the transplanted organ. One hundred and sixty-four kidney transplant patients were assessed using the Spielberger Anxiety Inventory, the Beck’s Depression Scale, the Posttraumatic Growth Inventory, the Brief Illness Perception Questionnaire, and the Transplanted Organ Questionnaire. Medical parameters were collected from the routine clinical blood tests (serum creatinine and estimated glomerular filtration rate levels) and biopsy results. Our most outstanding results suggest that kidney-transplanted patients’ illness representations are associated with health outcomes. The Transplanted Organ Questionnaire “psychological rejection” subscale was connected with higher serum creatinine and estimated glomerular filtration rate levels. Logistic regression analysis showed that psychological rejection subscale, Brief Illness Perception Questionnaire, and Posttraumatic Growth Questionnaire total scores were associated with graft rejection. These results may serve as a basis for the development of complex treatment interventions, which could help patients to cope with the bio-psycho-social challenges of integrating the new organ as part of their body and self. Keywords: anxiety, depression, illness representations, posttraumatic growth, psychological rejection, renal transplantatio

The yeast dynein Dyn2-Pac11 complex is a dynein dimerization/processivity factor: structural and single-molecule characterization

Cytoplasmic dynein is the major microtubule minus end–directed motor. Although studies have probed the mechanism of the C-terminal motor domain, if and how dynein's N-terminal tail and the accessory chains it binds regulate motor activity remain to be determined. Here, we investigate the structure and function of the Saccharomyces cerevisiae dynein light (Dyn2) and intermediate (Pac11) chains in dynein heavy chain (Dyn1) movement. We present the crystal structure of a Dyn2-Pac11 complex, showing Dyn2-mediated Pac11 dimerization. To determine the molecular effects of Dyn2 and Pac11 on Dyn1 function, we generated dyn2Δ and dyn2Δpac11Δ strains and analyzed Dyn1 single-molecule motor activity. We find that the Dyn2-Pac11 complex promotes Dyn1 homodimerization and potentiates processivity. The absence of Dyn2 and Pac11 yields motors with decreased velocity, dramatically reduced processivity, increased monomerization, aggregation, and immobility as determined by single-molecule measurements. Deleting dyn2 significantly reduces Pac11-Dyn1 complex formation, yielding Dyn1 motors with activity similar to Dyn1 from the dyn2Δpac11Δ strain. Of interest, motor phenotypes resulting from Dyn2-Pac11 complex depletion bear similarity to a point mutation in the mammalian dynein N-terminal tail (Loa), highlighting this region as a conserved, regulatory motor element