University of Ljubljana

About: University of Ljubljana is a education organization based out in Ljubljana, Slovenia. It is known for research contribution in the topics: Population & Liquid crystal. The organization has 17210 authors who have published 47013 publications receiving 1082684 citations. The organization is also known as: Univerza v Ljubljani.

Experimental constraints on the spin and parity of the Z(4430)

Abstract: We report the results of several studies of the Λc+π+π-X final state in continuum e+e- annihilation data collected by the Belle detector. An analysis of angular distributions in Λc(2880)+→Σc(2455)0, ++π+,- decays strongly favors a Λc(2880)+ spin assignment of 52 over 32 or 12. We find evidence for Λc(2880)+→Σc(2520)0,++π+,- decay and measure the ratio of Λc(2880)+ partial widths Γ(Σc(2520)π)/Γ(Σc(2455)π)=0.225±0. 062±0.025. This value favors the Λc(2880)+ spin-parity assignment of 52+ over 52-. We also report the first observation of Λc(2940) +→Σc(2455)0,++π+,- decay and measure Λc(2880)+ and Λc(2940)+ mass and width parameters. These studies are based on a 553fb-1 data sample collected at or near the Υ(4S) resonance at the KEKB collider. © 2007 The American Physical Society.

Electrochemotherapy with Cisplatin: Clinical Experience in Malignant Melanoma Patients

Abstract: Electrochemotherapy consists of chemotherapy followed by local application of electric pulses to the tumor to increase drug delivery into the cells. The aim of this Phase II clinical study was to evaluate the antitumor effectiveness of electrochemotherapy using intratumoral cisplatin administration on cutaneous tumor nodules in malignant melanoma patients. In 10 patients, 133 tumor nodules of different sizes were treated: (a) 82 tumor nodules were treated with electrochemotherapy; (b) 27 tumor nodules were treated with cisplatin; (c) 2 tumor nodules were treated with electric pulses; and (d) 22 tumor nodules were untreated. Four weeks after therapy, 78% objective responses were obtained in the electrochemotherapy group, and 38% objective responses were obtained in the cisplatin group. Exposure of tumor nodules to electric pulses without cisplatin treatment had no effect on tumor growth. Electrochemotherapy was well tolerated by all patients, and a good cosmetic effect was obtained, with only minimal scarring and a slight depigmentation of the skin. At 124 weeks of follow-up, a 77% control rate of the tumor nodules treated by electrochemotherapy was observed, compared to 19% for those that were treated with cisplatin only (P < 0.0001). Our results clearly demonstrate that electrochemotherapy with cisplatin is a highly effective approach for treatment of cutaneous malignant melanoma nodules. The advantages of this therapy include its simplicity, the short duration of treatment sessions, low cisplatin doses, and insignificant side effects, as well as the fact that it can be done on an outpatient basis.

Thaumarchaeal Ammonia Oxidation in an Acidic Forest Peat Soil Is Not Influenced by Ammonium Amendment

Abstract: Both bacteria and thaumarchaea contribute to ammonia oxidation, the first step in nitrification. The abundance of putative ammonia oxidizers is estimated by quantification of the functional gene amoA, which encodes ammonia monooxygenase subunit A. In soil, thaumarchaeal amoA genes often outnumber the equivalent bacterial genes. Ecophysiological studies indicate that thaumarchaeal ammonia oxidizers may have a selective advantage at low ammonia concentrations, with potential adaptation to soils in which mineralization is the major source of ammonia. To test this hypothesis, thaumarchaeal and bacterial ammonia oxidizers were investigated during nitrification in microcosms containing an organic, acidic forest peat soil (pH 4.1) with a low ammonium concentration but high potential for ammonia release during mineralization. Net nitrification rates were high but were not influenced by addition of ammonium. Bacterial amoA genes could not be detected, presumably because of low abundance of bacterial ammonia oxidizers. Phylogenetic analysis of thaumarchaeal 16S rRNA gene sequences indicated that dominant populations belonged to group 1.1c, 1.3, and "deep peat" lineages, while known amo-containing lineages (groups 1.1a and 1.1b) comprised only a small proportion of the total community. Growth of thaumarchaeal ammonia oxidizers was indicated by increased abundance of amoA genes during nitrification but was unaffected by addition of ammonium. Similarly, denaturing gradient gel electrophoresis analysis of amoA gene transcripts demonstrated small temporal changes in thaumarchaeal ammonia oxidizer communities but no effect of ammonium amendment. Thaumarchaea therefore appeared to dominate ammonia oxidation in this soil and oxidized ammonia arising from mineralization of organic matter rather than added inorganic nitrogen.

Epigenetic regulation of microRNAs in cancer: An integrated review of literature

Abstract: MicroRNAs (miRNAs) belong to the heterogeneous class of non-coding RNAs (ncRNAs) that regulate the translation and degradation of target mRNAs, and control approximately 30% of human genes. MiRNA genes might be silenced in human tumors (oncomiRs) by aberrant hypermethylation of CpG islands that encompass or lie adjacent to miRNA genes and/or by histone modifications. We performed literature search for research articles describing epigenetically regulated miRNAs in cancer and identified 45 studies that were published between 2006 and 7/2010. The data from those papers are fragmented and methodologically heterogeneous and our work represents first systematic review towards to integration of diverse sets of information. We reviewed the methods used for detection of miRNA epigenetic regulation, which comprise bisulfite genomic sequencing PCR (BSP), bisulfite pyrosequencing, methylation specific PCR (MSP), combined bisulfite restriction analysis (COBRA), methylation sensitive single nucleotide primer extension (Ms-SNuPE), MassARRAY technique and some modifications of those methods. This integrative study revealed 122 miRNAs that were reported to be epigenetically regulated in 23 cancer types. Compared to protein coding genes, human oncomiRs showed an order of magnitude higher methylation frequency (11.6%; 122/1048 known miRNAs). Nearly half, (45%; 55/122) epigenetically regulated miRNAs were associated with different cancer types, but other 55% (67/122) miRNAs were present in only one cancer type and therefore representing cancer-specific biomarker potential. The data integration revealed miRNA epigenomic hot spots on the chromosomes 1q, 7q, 11q, 14q and 19q. CpG island analysis of corresponding miRNA precursors (pre-miRNAs) revealed that 20% (26/133) of epigenetically regulated miRNAs had a CpG island within the range of 5kb upstream, among them 14% (19/133) of miRNAs resided within the CpG island. Our integrative survey and analyses revealed candidate cancer-specific miRNA epigenetic signatures which provide the basis for new therapeutic strategies in cancer by targeting the epigenetic regulation of miRNAs.

Combining reconstructive and discriminative subspace methods for robust classification and regression by subsampling

Abstract: Linear subspace methods that provide sufficient reconstruction of the data, such as PCA, offer an efficient way of dealing with missing pixels, outliers, and occlusions that often appear in the visual data. Discriminative methods, such as LDA, which, on the other hand, are better suited for classification tasks, are highly sensitive to corrupted data. We present a theoretical framework for achieving the best of both types of methods: an approach that combines the discrimination power of discriminative methods with the reconstruction property of reconstructive methods which enables one to work on subsets of pixels in images to efficiently detect and reject the outliers. The proposed approach is therefore capable of robust classification with a high-breakdown point. We also show that subspace methods, such as CCA, which are used for solving regression tasks, can be treated in a similar manner. The theoretical results are demonstrated on several computer vision tasks showing that the proposed approach significantly outperforms the standard discriminative methods in the case of missing pixels and images containing occlusions and outliers.