Expression of bone-related proteins in vascular calcification and its serum correlations with coronary artery calcification score.

Since vascular calcification is considered a process regulated similar to that of bone tissue mineralization, we investigated the participation of bone formation proteins. We analyzed the correlation of serum circulating bone markers, osteoprotegerin (OPG) and receptor activator of nuclear factor ĸB ligand (RANKL) in chronic kidney disease (CKD) patients, to coronary artery calcification score. We also considered the effect of inorganic phosphate on pro- and anti-calcifying tissue factors. We confirmed that circulating OPG is an independent calcium score predictor with its high serum concentration favoring high coronary artery calcification. In tissue samples of non-diseased human renal arteries, the expression of OPG and receptor activator of nuclear factor ĸB (RANK) was positive, while expression of RANKL was absent. In atherosclerotic specimens and arteries with medial calcification, the most upregulated was expression of bone morphogenetic proteins, BMP-2 and BMP-7, as well as expression of RANK and RANKL. In the diseased arteries, OPG expression was present only in areas where bone structures were formed. In atherosclerotic and medial calcification arteries, loss of alpha-smooth muscle actin (α-SMA) expression was observed. These data suggest a possible regulatory role of the examined proteins, especially OPG and RANKL, in vascular calcification, as well as their possible clinical significance as circulating predictors of vascular calcification.

Genetic diversity and structure of Slovenian native germplasm of plum species (P. domestica L., P. cerasifera Ehrh. and P. spinosa L.).

Slovenia has particular climatic, soil, geographic and historical conditions that lead to long tradition of plum cultivation and use. In this work, a set of 11 SSR and three universal cpDNA markers, as well as flow cytometry, were used to (1) evaluate the genetic diversity of 124 accessions of the three Prunus species (P. domestica L., P. cerasifera Ehrh., and P. spinosa L.), (2) investigate the possible involvement of P. cerasifera and P. spinosa species in P. domestica origin, (3) study the genetic relationships and variability among the most typical P. domestica accessions present in Slovenia. Ten haplotypes of cpDNA were identified and clustered into three groups according to the Neighbor-Joining analysis (NJ). All 11 SSR primer pairs were polymorphic, revealing 116 unique genotypes. A total of 328 alleles were detected with an average value of 29.82 alleles per locus, showing relatively high diversity. Bayesian analysis of genetic structure was used to identify two ancestral populations in the analyses of all three species as well as in a separate set consisting of P. domestica material only. Principal Coordinate Analysis (PCoA) showed that accessions clustered largely in agreement with Bayesian analysis. Neighbor-Joining analysis grouped 71 P. domestica accessions into three clusters with many subgroups that exhibited complex arrangement. Most accessions clustered in agreement with traditional pomological groups, such as common prunes, mirabelle plums and greengages. In this study, the analyses revealed within P. domestica pool valuable local landraces, such as traditional prunes or bluish plums, which seem to be highly interesting from a genetic point of view. Moreover, complementary approaches allowed us to distinguish between the three species and to gain insights into the origin of plum. The results will be instrumental in understanding the diversity of Slovenian plum germplasm, improving the conservation process, recovering local genotypes and enriching existing collections of plant genetic resources.

Hybrid performance in taro (Colocasia esculenta) in relation to genetic dissimilarity of parents.

Taro (Colocasia esculenta) breeding, as other root crop breeding, is based on the production and evaluation of large numbers of hybrids. The selection of parents is based on their phenotypic value in the absence of information concerning general combining ability (GCA), specific combining ability (SCA), or genetic distances between varieties. By combining data from heritability trials and from genetic diversity studies conducted with AFLP and SSR markers, we aimed at studying the relationship between hybrid vigour and genetic dissimilarity between parents. The traits studied included number of suckers, corm weight, corm dimensions, and dry matter content. Correlation coefficients between hybrid gain and dissimilarity values were calculated. The prediction of hybrid performance based on the mid-parent value was compared to the prediction based on a modified expression that takes into account the genetic relationships between parents. Correlations were all but one positive but not statistically significant for all traits, with the exception of the number of suckers, when using SSR markers for dissimilarity calculations. Accordingly, the genetic dissimilarities in the prediction of hybrid performances did not increase the correlation between predicted and observed hybrid vigour values. However, large differences were observed among the residual means from the regression between predicted and observed values when using AFLP or SSR markers, mainly due to the much higher polymorphism revealed by the latter. Models need to be further adapted to the type of molecular marker used, since their ability to reveal different rates of polymorphism will have a direct incidence on the calculation of genetic dissimilarities between genotypes. Nevertheless, since SSR markers are more polymorphic and more informative than AFLP markers, they should be preferentially used for these studies. Low genetic dissimilarity of parents yielded weak heterosis effects and future studies need to be conducted by using a broader genetic base. This is the first study assessing the relationship of hybrid vigour with the genetic distances between parents, conducted on a tropical root crop.

Vascular complications after 725 kidney transplantations during 3 decades.

Among 725 renal transplantations, the most common vascular complication was arterial stenosis, which was observed in 23 patients (3.17%). The majority of 20 (6.49%) arterial stenoses appeared in our initial experiences when we routinely used end-to-end renal graft to internal iliac artery anastomoses. A significant reduction in this incidence (0.72%) was achieved by introducing end-to-side anastomoses of the renal graft artery to the external or common iliac arteries. Intractable hypertension or impaired renal function in 14 patients (60.87%) with arterial stenosis demanded treatment. Patch angioplasty was more successful than other methods. The limited possibilities of conservative treatment of arterial hypertension at that time were the main reason for this frequent surgical repair. Among other vascular complications, the most serious were 12 episodes of arterial bleeding in 10 patients. Five kidneys were lost because of ruptured arterial anastomoses. In 6 patients, the common or external iliac artery was ligated as to achieve hemostasis with acute arterial insufficiency of the lower extremity in 4 patients. One patient required leg amputation, whereas 2 underwent extra-anatomic bypass procedures and 1 died because of hepatic failure. The majority of vascular complications occurred in the initial period of our transplantation practice. However, in spite of progress in diagnostic and treatment options, vascular complications may cause considerable clinical problems.

Flail chest stabilization with palacos prosthesis.

The approach and management of patients with post-traumatic flail chest continue to be a controversial issue. A method of surgical stabilization of flail chest using palacos, a cement-like material is described. A ready-made prosthesis is placed on the external side of the ribs vertically bridging the flailed chest segment, and fixed to the first upper and first lower intact rib as well as to the mobile segments of the affected ribs. Surgical fixation was carried out in 56 patients. The results proved the method to be a simple and effective procedure.