Determinative Value of a Portion of the nifH Sequence for the Genera Nostoc and Anabaena (Cyanobacteria)

The taxonomic positions of Nostoc and Anabaena strains are currently disputed. We selected three Nostoc and Anabaena strains, using the classic criteria of morphology and life cycle. DNA sequences of a part of the nifH gene were determined from these strains and aligned with homologous sequences from 10 other Nostoc/Anabaena strains in the public databases. Phylogenetic reconstructions were carried out to test the consistency of the taxonomic placement of these strains. The phylogenetic trees do not separate these strains into distinct groups. Our results are in agreement with other molecular-based phylogenies that also fail to differentiate the Nostoc-Anabaena groups. The data suggest that the currently recognized genera Nostoc and Anabaena may in fact belong within a single, broadly defined genus. Received: 14 February 2000 / Accepted: 21 March 2000     

Virilizing adrenal cancer and bail-out nephrectomy

We report a rare case of virilizing adrenal cancer with tumorous invasion of the left renal vein in which a retroperitoneal adrenalectomy with bail-out nephrectomy was performed. A tumor thrombus infiltrated the wall of the left adrenal vein and extended into the left renal vein. Initially, a kidney sparing procedure with partial tangential excision of the involved renal vein wall was performed. After positive vein margins were confirmed with intraoperative histology, the indication for nephrectomy was made. To the authors' awareness, this is the first report of a virilizing adrenal cancer with a tumor thrombus infiltration of the renal vein and surgical tendency for kidney preservation.     

Consistency of genome-based methods in measuring Metazoan evolution

Seven distinct genome-wide divergence measures were applied pairwise to the nine sequenced animal genomes of human, mouse, rat, chicken, pufferfish, fruit fly, mosquito, and two nematode worms (Caenorhabditis briggsae and Caenorhabditis elegans). Qualitatively, all of these divergence measures are found to correlate with the estimated time since speciation; however, marked deviations are observed in a few lineages. The distinct genome divergence measures also correlate well among themselves, indicating that most of the processes shaping genomes are dominated by neutral events. The deviations from the clock-like scenario in some lineages are observed consistently by several measures, implicitly confirming their reliability.     

The effect of radiation on pedicled TRAM flap breast reconstruction: outcomes and implications

The purpose of this study was to examine the effect of postreconstruction radiation therapy on patients undergoing pedicled TRAM flap breast reconstruction. Post-TRAM radiation patients were compared with patients who received pre-TRAM radiation and a control TRAM-only group who received no radiation. Overall aesthetic appearance, evidence of symmetry, flap contracture, and hyperpigmentation were assessed by blinded reviewers. A total of 171 pedicled TRAM reconstructions were performed in 150 patients. Total flap complications were seen in 49.5 percent of the control patients, 57.1 percent of pre-TRAM radiation patients, and 50 percent of post-TRAM radiation patients but were not statistically different. The complete flap necrosis rate was 0.6 percent and the partial flap necrosis rate was 7.6 percent, again with no statistical differences among the groups. Donor-site complications occurred in approximately one third of patients in each of the groups. Deep venous thrombosis and pulmonary embolus each occurred once and only in the post-TRAM radiation group. In terms of overall aesthetic outcome, symmetry, and contracture, the control group consistently rated better than the pre-TRAM (p = 0.021, p = 0.03, p = 0.03, respectively) and the post-TRAM (p = 0.0001, p = 0.0001, and p =0.0001, respectively) radiation groups. The control group also had clinically and statistically significant less hyperpigmentation than the post-TRAM radiation group (p = 0.0002). In contrast, irradiated postreconstruction patients had scores, including aesthetic outcome, symmetry, and contracture, worse than those of irradiated prereconstruction patients. When these two groups were compared with each other, except for contracture, no statistical significance, because of a small patient sample, was found. Neither preoperative nor postoperative radiation increased the risk for flap or donor-site complications. In contrast, radiation of any type did affect aesthetic appearance, symmetry, contracture, and hyperpigmentation. The authors recommend that TRAM flap breast reconstruction be postponed in those patients known or expected to receive postmastectomy radiation.     

Glucosinolate distribution in aerial parts of Degenia velebitica

The glucosinolates present in the leaf, stem, and seed extracts of Degenia velebitica (Degen) Hayek were characterized and quantified according to the ISO 9167-1 method, which is based on the HPLC analysis of desulfoglucosinolates. The stems contained glucoalyssin (3a) as the major compound as well as glucoberteroin (1a) and glucoaubrietin (4a). The leaves contained three glucosinolates, the major one being 3a, followed by glucobrassicanapin (2a) and 1a. Glucoberteroin (1a) was the major glucosinolate in the seeds, along with the two minor glucosinolates 3a and glucoerucin (5a). The content of 1a in the whole, non-defatted seeds amounted to 4% (w/w). The compound was characterized as its desulfo counterpart by spectroscopic techniques.     

Evidence for Distinct Functions of MRE11 in Arabidopsis Meiosis

The evolutionary conserved Mre11/Rad50/Nbs1 complex functions as one of the guardians of genome integrity in eukaryotes; it is required for the double-strand break repair, meiosis, DNA checkpoint, and telomere maintenance. To better understand the role of the MRE11 gene in Arabidopsis, we performed comparative analysis of several mre11 alleles with respect to genome stability and meiosis. The mre11-4 and mre11-2 alleles presumably produce truncated MRE11 proteins composed of the first 499 and 529 amino acids, respectively. Although the putative MRE11 truncated proteins differ only by 30 amino acids, the mutants exhibited strikingly different phenotypes in regards to growth morphology, genome stability and meiosis. While the mre11-2 mutants are fully fertile and undergo normal meiosis, the mre11-4 plants are sterile due to aberrant repair of meiotic DNA breaks. Structural homology analysis suggests that the T-DNA insertion in the mre11-4 allele probably disrupted the putative RAD50 interaction and/or homodimerization domain, which is assumed to be preserved in mre11-2 allele. Intriguingly, introgression of the atm-2 mutant plant into the mre11-2 background renders the double mutant infertile, a phenotype not observed in either parent line. This data indicate that MRE11 partially compensates for ATM deficiency in meiosis of Arabidopsis.     

Multiple origins of European populations of the giant liver fluke Fascioloides magna (Trematoda: Fasciolidae), a liver parasite of ruminants

The giant liver fluke, Fascioloides magna, a liver parasite of free-living and domestic ruminants of Europe and North America, was analysed in order to determine the origin of European populations and to reveal the biogeography of this originally North American parasite on the European continent. The variable fragments of the mitochondrial cytochrome c oxidase subunit I (cox1; 384bp) and nicotinamide dehydrogenase subunit I (nad1; 405bp) were used. Phylogenetic trees and haplotype networks were constructed and the level of genetic structuring was evaluated using population genetic tools. In F. magna individuals originating from all European foci of infection (Italy, Czech Republic and Danube floodplain forests involving the territories of Slovakia, Hungary and Croatia) and from four of five major North American enzootic areas, 16 cox1 and 18 nad1 haplotypes were determined. The concatenated sequence set produced 22 distinct haplotypes. The European fluke populations were less diverse than those from North America in that they contained proportionately fewer haplotypes (eight), while a more substantial level of genetic diversity and a greater number of haplotypes (15) were recorded in North America. Only one haplotype was shared between the European (Italy) and North American (USA/Oregon and Canada/Alberta) flukes, supporting a western North American origin of the Italian F. magna population. Haplotypes found in Italy were distinct from those determined in the remaining European localities which indicates that introduction of F. magna to the European continent occurred more than once. In the Czech focus of infection, a south-eastern USA origin was revealed. Identical haplotypes, common to parasites from the Czech Republic and from an expanding focus in Danube floodplain forests, implies that the introduction of F. magna to the Danube region came from an already established Czech focus of infection.