Background-Cell replacement therapy with stem cells able to differentiate into cardiomyocytes has been discussed as a method for remodeling damaged myocardium. A physiological or pathophysiological situation in which this phenomenon might be relevant is not known. We studied the origin of cardiomyocytes in myocardial biopsies of male patients that had undergone sex-mismatched cardiac transplantation to determine whether cells containing a Y chromosome (and therefore being of recipient origin) are able to differentiate into cardiomyocytes. Methods and Results-Myocardial biopsies (nϭ21) were obtained from the right ventricles of male patients (nϭ13) who had undergone sex-mismatched heart transplantation. Tissue from 1 nontransplanted male and myocardial biopsies from sex-matched heart-transplanted patients served as controls. Cells from donor and recipient origins were identified by fluorescence in situ hybridization with the use of specific probes for X and Y chromosomes on paraffin sections of the biopsies. Cell types were identified by using immunostaining procedures on the same tissue sections. Cardiomyocytes of recipient origin were detected in 8 of 13 male recipients of female hearts. They were connected by gap junctions with adjacent myocytes. Of the cardiomyocyte nuclei, 0.16Ϯ0.04% (meanϮSEM, median 0.09%) contained the Y-chromosomal marker. There was no detectable correlation with the extent or number of rejection episodes, time of transplantation, or medical treatment regimen. Conclusions-These results show that regeneration by cells of noncardiac origin (differentiated into cardiomyocytes and physiologically linked to neighboring myocytes) can be detected even in small myocardial biopsies. This may lead to new diagnostic and therapeutic strategies in the treatment of myocardial infarction, inflammatory heart disease, and/or heart failure.

Sour cherry (Prunus cerasus L.) cultivars native to Hungary and some of them grown worldwide, display great phenotypic variability. Eleven sour cherry cultivars were analysed for their main quality attributes including fruit weight, soluble solid content, acidity, pH, specific sugars (glucose and fructose), antioxidant capacity as well as total polyphenolic (TPC), total anthocyanin (TMAC) and vitamin C contents. Results showed wide variation in both fruit quality and antioxidant parameters of Hungarian sour cherries. The anthocyanin contents varied from 11.3 to 93.5 mg ⁄ 100 g. An amarelle-type cultivar, 'Pipacs 1' showed the highest antioxidant capacity (21.85 mmol AA L )1 ), TPC (49.04 mg GA L )1 ) and vitamin C (8.98 mg ⁄ 100 g) content. Key enzymes in anthocyanin biosynthesis were expressed in both yellow-coloured flesh and red skin of 'Pipacs 1' fruits at all ripening stages. The detected diversity presents a choice that can satisfy different consumer preferences, and meet specific nutritional requirements.

A total of 13 killer toxin producing strains belonging to the genera Saccharomyces, Candida and Pichia were tested against each other and against a sensitive yeast strain. Based on the activity of the toxins 4 different toxins of Saccharomyces cerevisiae, 2 different toxins of Pichia and one toxin of Candida were recognized. The culture filtrate of Pichia and Candida showed a much smaller activity than the strains of Saccharomyces. Extracellular killer toxins of 3 types of Saccharomyces were concentrated and partially purified. The pH optimum and the isoelectric point were determined. The killer toxins of S. cerevisiae strain NCYC 738, strain 399 and strain 28 were glycoproteins and had a molecular weight of Mr = 16,000. The amino acid composition of the toxin type K2 of S. cerevisiae strain 399 was determined and compared with the composition of two other toxins.

Over the course of several million years, the eukaryotic gut symbionts of lower termites have become adapted to a cellulolytic environment. Up to now it has been believed that they produce nutriments using their own cellulolytic enzymes for the benefit of their termite host. However, we have now isolated two endoglucanases with similar apparent molecular masses of approximately 36 kDa from the not yet culturable symbiotic Archaezoa living in the hindgut of the most primitive Australian termite, Mastotermes darwiniensis. The N-terminal sequences of these cellulases exhibited significant homology to cellulases of termite origin, which belong to glycosyl hydrolase family 9. The corresponding genes were detected not in the mRNA pool of the flagellates but in the salivary glands of M. darwiniensis. This showed that cellulases isolated from the flagellate cells originated from the termite host. By use of a PCR-based approach, DNAs encoding cellulases belonging to glycosyl hydrolase family 45 were obtained from micromanipulated nuclei of the flagellates Koruga bonita and Deltotrichonympha nana. These results indicated that the intestinal flagellates of M. darwiniensis take up the termite's cellulases from gut contents. K. bonita and D. nana possess at least their own endoglucanase genes, which are still expressed, but without significant enzyme activity in the nutritive vacuole. These findings give the impression that the gut Archaezoa are heading toward a secondary loss of their own endoglucanases and that they use exclusively termite cellulases.Cellulose is the major polysaccharide component of plant cell walls and the most abundant renewable energy source on earth. In the biological conversion of cellulose to glucose, at least three distinct types of glycolytic enzymes are involved. Endoglucanases (endo-1,4-␤-glucanase, EC 3.2.1.4) randomly hydrolyze 1,4-␤ bonds of the cellulose chains. Cellobiohydrolases (exo-1,4-␤-glucanase, EC 3.2.1.91) cleave cellobiosyl units from nonreducing ends of the cellullose chains. ␤-Glucosidases (EC 3.2.1.21) cleave glucosyl units from nonreducing ends of cello-oligosaccharides. The diverse spectra of cellulases are classified into 12 of the 57 glycosyl hydrolase families based on amino acid sequence similarities (5).Termites are among the most important lignocellulose-digesting insects and possess a great variety of symbiotic microorganisms in their hindguts, including Bacteria, Archaea and Eukarya, i.e., protozoa and yeasts (7). In the digestive tracts of lower termites, cellulose seems to be synergistically degraded by flagellates, bacteria, and yeasts (3, 7, 15) as well as by the termiteЈs own cellulases (14, 17). Cellulases of termite origin belong to glycosyl hydrolase family 9 (GHF9). Flagellated protozoa belonging to the Archaezoa are unique symbionts in the phylogenetically lower termites. They are cellulolytic and produce acetate from cellulose for the benefit of their hosts (10). The termite Mastotermes darwiniensis is the only species of the most primitive termite family, M...

Two apricot genotypes, 'Gönci magyarkajszi' and 'Preventa' were assayed at three ripening stages for fl esh color indices (L*, a*, b*, C* and H o), contents of total phenolics and vitamin C, and both water-and lipid-soluble antioxidant capacities (ferric reducing antioxidant power; 2,2'-diphenyl-1-picrylhydrazyl scavenging activity; total radical scavenging activity; and Photochem lipid-soluble antioxidant capacity) to compare their dynamics in the accumulation of antioxidant compounds and capacities through ripening. The increase in a*, b* and C* and decrease in H o during ripening represented a color shift from green to yellow and orange due to carotenoid accumulation. Parallel to carotenoid accumulation, contents of total phenolics and vitamin C and antioxidant capacity increased signifi cantly (p ≤ 0.05) from unripe to fully ripe fruits. More phenolics and vitamin C accumulated in fully ripe fruits of 'Preventa' than 'Gönci magyarkajszi'. The accumulation patterns of these compounds were different: while the vitamin C contents in unripe fruit of 'Preventa' and 'Gönci magyarkajszi' were identical (approx. 6 mg/100 g fresh weight), unripe 'Preventa' contained even more phenolics (approx. 12 mmolGA/l) than fully ripe 'Gönci magyarkajszi' (8 mmolGA/l). Our results confi rm that fully ripe 'Preventa' fruits are characterized by outstanding functional properties due to the increased accumulation of vitamin C and phenolics throughout the ripening process.