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Chronic kidney disease (CKD) pre-heart transplantation (HTx) has been proposed as a risk factor for malignancy risk post-HTx. Using multicenter registry data, our aim was to calculate the death-adjusted annual incidence of malignancy post-HTx, corroborate the association between CKD pre-HTx and malignancy risk post-HTx, and determine other risk factors for post-HTx malignancy. We used data from patients transplanted in North American HTx centers between January 2000-June 2017 and registered in the International Society for Heart and Lung Transplantation Thoracic Organ Transplant Registry. We excluded recipients with missing data on post-HTx malignancy, heterotopic heart transplant, retransplantation, multi-organ transplantation, and patients with a total artificial heart pre-HTx. Overall, 34 873 patients were included to determine the annual incidence of malignancies, 33 345 patients were included in the risk analyses. The incidence of any malignancy, solid-organ malignancy, and post-transplant lymphoproliferative disease (PTLD), adjusted for death 15 years post-HTx, was 26.6%, 10.9%, and 3.6%, respectively. Besides widely acknowledged risk factors, CKD stage ≥4 pre-HTx was associated with the development of all malignancies post-HTx (HR 1.17 compared to CKD stage 1, p=0.023), as well as solid-organ malignancies (HR 1.35, p=0.01), but not for PTLD (HR 0.73, p=0.057), and skin cancer (HR 1.06, p=0.59). Risk of malignancy post-HTx remains high. CKD stages ≥4 pre-HTx was associated with an increased risk for any malignancy and solid-organ malignancy post-HTx. Strategies to mitigate the impact of pre-HTx patient factors on the risk of post-HTx malignancy are needed. [ABSTRACT FROM AUTHOR]

During the last 20 years many investigations have been carried out with respect to in vitro culture of different organs and tissues of the potato. So far, however, the results of attempts to realize shoot organogenesis and embryogenesis have been rather unsuccesful. Preliminary experiments with the potato clone EM 52 are described, with results which demonstrate the possibility of the production of numerous adventitious shoots on explants of the rachis of a compund leaf cultivated in vitro. After a subculture of the shoots, root formation could be induced and subsequently plantlets produced. [ABSTRACT FROM AUTHOR]

Transformed root lines were obtained after infection of leaf segments and tuber discs of tetraploid potato cvs Bintje and Desirée with Agrobacterium rhizogenes. In response to shoot induction, about 10% of the root lines produced shoots through callus formation. The tests for opine suggest that all 26 shoot lines of cv Bintje (Ri-Bintje) and 13 of Desirée (Ri-Desirée) were transformed. All shoot lines were tetraploid except for one octoploid subshoot line of cv Desirée; no aneuploids were observed. With the exception of two shoot lines derived from the same root line, all other Ri-Bintje plants showed a pattern of phenotypic variation, generally observed among transformed plants. In contrast, the phenotype of Ri-Desirée plants was uniform and normal; variation was observed in tuber form and size. Phenotypic variation observed among Ri-plants appeared to be mainly root line-dependent, particularly for height of plants and tuber size and form. Variation was also observed within root and shoot lines and was more pronounced among the Ri-Bintje plants. Segregation of phenotypic characteristics was observed among transformed plants, resulting in the occurrence of phenotypes resembling the control. Chromosomal stability and the frequent reversion to normal phenotype of Ri-plants make A. rhizogenes particularly suitable as a virulence vector in the binary transformation system for the transfer of desirable genes. [ABSTRACT FROM AUTHOR]

An investigation was made on the origin and basis of somaclonal variation in potato. Plants were regenerated from protoplasts of dihaploid and tetraploid potato, and the degree of variation in phenotype and chromosome number was analyses. All the regenerants from dihaploid potato showed variation in chromosome number, while only part of these varied in plant morphology. In tetraploid potato, 60 % of the regenerants showed variation in chromosome number, all of which exhibited phenotypic changes. The data suggest that the explant source and the initial ploidy level of the genotype play an important role in influencing the degree of somaclonal variation. [ABSTRACT FROM AUTHOR]