Analysis of the Wnt/B-catenin/TCF4 pathway using SAGE,genome-wide microarray and promoter analysis: Identification of BRI3 and HSF2 as novel targets

The Wnt signaling pathway is involved in many differentiation events during embryonic development and can lead to tumor formation after aberrant activation of its components. β-catenin, a cytoplasmic component, plays a major role in the transduction of canonical Wnt signaling. The aim of this study was to identify novel genes that are regulated by active β-catenin/TCF signaling in hepatocellular carcinoma-derived Huh7 cells with high (transfected) and low β-catenin/TCF activities. High TCF activity Huh7 cells led to earlier and larger tumor formation when xenografted into nude mice. SAGE (Serial Analysis of Gene Expression), genome-wide microarray and in silico promoter analysis were performed in parallel, to compare gene expression between low and high β-catenin/TCF activity clones, and also those that had been rescued from the xenograft tumors. SAGE and genome-wide microarray data were compared and contrasted. BRI3 and HSF2 were identified as novel targets of Wnt/β-catenin signaling after combined analysis and confirming experiments including qRT-PCR, ChIP, luciferase assay and lithium treatment.     

An alternative approach to the traditional mixotrophic cultures of Haematococcus pluvialis Flotow (Chlorophyceae)

In traditional mixotrophic cultures of microalgae, all the inorganic nutrients and organic carbon sources are supplied in the medium before inoculation. In this study, however, an alternative approach was adopted in Haematococcus pluvialis Flotow, a microalga capable of growing mixotrophically on sodium acetate (Na-Ac). First, the cells were grown under 75 micromol photons m-2 s-1 phototrophically without Na-Ac until the stationary phase and then exposed to five different light regimes by the addition of Na-Ac, e.g., dark, 20, 40, 75 and 150 micromol photons m-2 s-1. Dry weight (DW), pigments and especially cell number in alternative mixotrophy (AM) were higher than traditional mixotrophy (TM). Cell number in AM almost doubled up from 21.7 to 42.9 x 104 cells mL-1 during 5 day exposure to Na-Ac, whereas the increase was only 1.2-fold in TM. Maximum cell density was reached in 75 micromol photons m-2 s-1 among the light intensities tested. We propose that Na-Ac in TM of H. pluvialis can not be utilized as efficient as in AM. With this respect, AM is of several advantages against TM such as a much higher cell density in a batch culture period and minimized risk of contamination due to the shorter exposure of cells to organic carbon sources. In consequence, this method may be used for other strains of the species, and even for the other microalgal species able to grow mixotrophically.     

Supramolecular cobalt(II)-pyridine-2,5-dicarboxylate complexes with isonicotinamide, 2-amino-3-methylpyridine and 2-amino-6-methylpyridine: Syntheses, crystal structures, spectroscopic, thermal and antimicrobial activity studies

The mer-[Co(pydca)(H₂O)₃(ina)]·H₂O (1), (2a3mpyH)₂[Co(pydca)₂(H₂O)₂]·2H₂O (2) and (2a6mpyH)₂[Co(pydca)₂(H₂O)₂]·2H₂O (3) complexes (H₂pydca: pyridine-2,5-dicarboxylic acid, ina: isonicotinamide, 2a3mpy = 2-amino-3-methylpyridine and 2a6mpy = 2-amino-6-methylpyridine) were synthesised and characterised by elemental analysis, magnetic and spectroscopic measurements (UV-Vis and IR spectra) and single crystal X-ray diffraction technique. The thermal behaviour of the complexes was also studied by simultaneous thermal analysis techniques (TG, DTG and DTA). In complex 1, Co(II) ion was coordinated by one bidentate pydca, one isonicotinamide and three aqua ligands to generate a CoN₂O₄ distorted octahedral geometry. Complexes 2 and 3 crystallise in the triclinic system and space group and the structures consist of one complex anion [Co(pydca)₂(H₂O)₂]²⁻, two protonated aminomethylpyridinium cations, ampyH⁺ and two crystal water molecules. In the anions, the Co(II) ions have a distorted octahedral configuration and are coordinated by two bidentate pydca and two trans-aqua ligands. The pydca ligand is coordinated to the Co(II) by both the heterocyclic N atom and the adjacent carboxylate group O atom, creating a chelate ring, while protonated ampy ions behave as counter ion.     

The diagnostic value of on-site cytopathological evaluation and cell block preparation in fine-needle aspiration cytology of liver masses

OBJECTIVE: The aims of this study were to evaluate the typing accuracy of conventional smear (CS), cell block (CB) preparations and combined use of both procedures (CS + CB) for the diagnosis of hepatic malignancies and to determine whether immediate on-site cytopathological evaluation improves the diagnostic yield of liver fine-needle aspiration cytology (FNAC). METHODS: Ultrasound-guided FNABs were performed on 323 consecutive cases with liver masses between December 2002 and December 2004. Histologically and/or clinically correlated 167 cases were included in the study. Preliminary FNAB results, results of CS, CB, and combined use of CS and CB were compared regarding diagnostic sensitivity, specificity, and accuracy for the diagnosis of malignancy. Subtyping accuracies of different methods were also compared. RESULTS: The sensitivity of on-site cytopathological examination and CS were both 92.8%. The sensitivity of CS + CB was slightly better than that of CB (93.5% versus 84.8%). Specificity of all procedures was achieved 100%. Diagnostic accuracy of on-site cytopathological evaluation, CS, CB, and CS + CB were 93.9%, 93.9%, 87.2%, and 94.5%, respectively. A specific subtype diagnosis of malignant tumours could be rendered accurately on the basis of preliminary diagnosis in 71%, CS in 75.4%, CB in 78.3% and combined approach in 92% of cases. In terms of typing accuracy, 87.5% of HCCs, 93.2% of adenocarcinomas, 92.3% of neuroendocrine carcinomas, 100% of lymphomas and 100% of other malignant tumours were correctly subclassified in the final cytopathological diagnosis. The agreement between preliminary diagnosis and final cytopathological diagnosis was 77.2%. CONCLUSION: With use of on-site cytopathological evaluation and combined use of CS and CB, the diagnostic accuracy of liver tumours approaches 100% and also significantly improve diagnostic and subtyping accuracy of liver malignancies.     

Genetic diversity of Vicia faba L. and Pisum sativum L. nodulating rhizobia in the central Black Sea region of Turkey

In this study, we obtained a total of 60 rhizobial isolates from root nodules of Vicia faba L. (n = 30) and Pisum sativum L. (n = 30) grown in the Central Black Sea region of Turkey. The 16S rDNA PCR-RFLP analysis with enzymes CfoI, HinfI, NdeII and MspI revealed a single pattern. Moreover, nucleotide sequence phylogenies based on both the 16S rDNA and recA suggested that these isolates belonged to Rhizobium leguminosarum. Phylogenetic analysis showed that some of our V. faba L.-originated isolates were closely related, indicating molecular evidence for the selection of some special R. leguminosarum bv. viciae isolates by V. faba L., as suggested in previous studies. Network analysis based on recA sequences revealed a common evolutionary history for Turkish, European, North and South American, and Jordanian R. leguminosarum bv. viciae isolates. We isolated four haplotypes using nodA and nifH nucleotide sequence data, i.e. four types of sym plasmids. Two of these types were common to rhizobial isolates from both V. faba L. and P. sativum L., indicating that nodulation factors may not be the mechanism for selection of the special R. leguminosarum bv. viciae populations by V. faba L.     

Taxonomic differentiation of Cupressus sempervirens and C. atlantica based on morphometric evidence

We investigated the interspecific morphological relationships of two related Mediterranean Cupressus taxa and the possible geographic differentiation of Eastern Mediterranean C. sempervirens using morphometric analysis. A total of 446 individuals, representing eight C. atlantica (Morocco) and 10 C. sempervirens (Greece, Turkey and Lebanon) populations were examined. The 17 morphological characters of cone, seed and shoot with leaves were measured and analysed statistically. Significant morphological differences between C. atlantica and C. sempervirens were detected for the majority of analysed characters. For C. sempervirens, significant differences were also detected and these were related to its three regions of origin, the Greek Islands, Taurus Mts and Lebanon Mts. Multivariate analyses did not indicate a clear geographic pattern of differentiation in C. sempervirens populations. A relatively low level of phenotypic differentiation was detected between populations originating from the Greek Islands and Taurus Mts. We also observed a moderate multivariate differentiation between the Lebanese and remaining C. sempervirens populations. Phenotypic differentiation detected in the Asian part of the C. sempervirens range reflects patterns of differentiation similar to those described for other taxa occurring in the Taurus and Lebanon Mts.