New chromosome counts in the genus Centaurea (Asteraceae) from Turkey

Twenty‐two chromosome counts are reported in 16 species, four subspecies and two varieties of the genus Centaurea. These are mostly Turkish local endemics of section Cheirolepis, a complicated group from the Eastern clade of the Jacea group. Twenty‐one reports are new. Prevalence of the basic chromosome number x = 9 among the eastern sections of the Jacea group is confirmed. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159 , 280–286.     

Carbonic anhydrase inhibitors. Inhibition of human erythrocyte isozymes I and II with a series of antioxidant phenols

The inhibition of two human cytosolic carbonic anhydrase (hCA, EC 4.2.1.1) isozymes I and II, with a series of phenol derivatives was investigated by using the esterase assay, with 4-nitrophenyl acetate as substrate. 2,6-Dimethylphenol, 2,6-diisopropylphenol (propofol), 2,6-di-t-butylphenol, butylated hydroxytoluene, butylated hydroxyanisole, vanillin, guaiacol, di(2,6-dimethylphenol), di(2,6-diisopropylphenol), di(2,6-di-t-butylphenol), and acetazolamide showed K_I values in the range of 37.5–274.5 μM for hCA I and of 0.29–113.5 μM against hCA II, respectively. All these phenols were non-competitive inhibitors with 4-nitrophenylacetate as substrate. Some antioxidant phenol derivatives investigated here showed effective hCA II inhibitory effects, in the same range as the clinically used sulfonamide acetazolamide, and might be used as leads for generating enzyme inhibitors possibly targeting other CA isoforms which have not been yet assayed for their interactions with such agents.     

Oxidative Stress in Helicobacter pylori Infection: Does Supplementation with Vitamins C and E Increase the Eradication Rate?

Aim: This study aims to assess the antioxidant property of vitamins E and C in Helicobacter pylori infection, and to determine if adding them to standard triple therapy plus bismuth subcitrate increases the H. pylori eradication rate. Methods: This study included 160 patients infected with H. pylori, who were randomized into one of two groups. Patients in group A (n = 80) received lansoprazole (30 mg, b.i.d.), amoxicillin (1000 mg, b.i.d.), clarithromycin (500 mg, b.i.d.), and bismuth subcitrate (300 mg, q.i.d.) for 14 days, while patients in group B (n = 80) received vitamin C (500 mg, b.i.d.) and vitamin E (200 IU, b.i.d.) for 30 days, in addition to lansoprazole (30 mg, b.i.d.), amoxicillin (1000 mg, b.i.d.), clarithromycin (500 mg, b.i.d.), and bismuth subcitrate (300 mg, q.i.d.) for 14 days. Total antioxidant capacity (TAC) was evaluated with a Randox kit. Success rate was calculated using both intention‐to‐treat (ITT) and per‐protocol (PP) analyses. Results: One hundred and sixty patients were analyzed using ITT analysis. One hundred and fifty‐three patients completed the study. In group A, H. pylori eradication was achieved in 48 (60%) of the 80 patients included in the ITT analysis, and in 48 (64%) of the 75 patients included in the PP analysis. In group B, H. pylori eradication was achieved in 73 (91.25%) of the 80 included in the ITT analysis and in 73 (93.5%) of the 78 patients included in the PP analysis. The eradication rate was significantly higher in group B than in group A (p < .005). TAC was at the lower limit of normal in both groups and the difference between them was not statistically significant (p > .05). Conclusion: In group B, H. pylori eradication rate was 91.25%, which is higher than the ideal 80% eradication rate. The results of the present study show that adding the prescribed doses of vitamins E and C to antimicrobial therapy is effective in eradicating H. pylori infection.     

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.     

A genetic system to assess in vivo the functions of histones and histone modifications in higher eukaryotes

Despite the fundamental role of canonical histones in nucleosome structure, there is no experimental system for higher eukaryotes in which basic questions about histone function can be directly addressed. We developed a new genetic tool for Drosophila melanogaster in which the canonical histone complement can be replaced with multiple copies of experimentally modified histone transgenes. This new histone‐replacement system provides a well‐defined and direct cellular assay system for histone function with which to critically test models in chromatin biology dealing with chromatin assembly, variant histone functions and the biological significance of distinct histone modifications in a multicellular organism.     

Screening of Biological Activities of a Series of Chalcone Derivatives against Human Pathogenic Microorganisms

In an effort to develop new antimicrobial agents, a series of chalcone derivatives, 3 – 60 , were prepared by Claisen–Schmidt condensation of appropriate acetophenones and 2‐furyl methyl ketones with appropriate aromatic aldehydes, furfural, and thiophene‐2‐carbaldehyde in an aqueous solution of NaOH and EtOH at room temperature. The synthesized compounds were characterized by means of their IR‐ and NMR‐spectral data, and elemental analysis. All compounds were tested for their antibacterial and antifungal activities by the disc diffusion method. For the most active compounds, also minimum inhibitory concentrations (MICs) were determined.     

The mutagenic and antimutagenic effects of Ecballium elaterium fruit juice in human peripheral lymphocytes

The aim of this study was to investigate the mutagenic and antimutagenic effects of Ecballium elaterium (EE) fruit juice, which has an anti-inflammatory effect, using in vitro human peripheral lymphocytes. To investigate the mutagenic effects of the EE fruit juice, human peripheral lymphocytes were treated with three doses (18, 36, and 72 μl/l) of fruit juice alone for 24 and 48 h. For investigating the antimutagenic effects of the EE fruit juice, the human lymphocytes were also treated with the mixture of the fruit juice and 0.25 μg/ml MMC. The EE fruit juice induced the percentage of total CA when used alone (especially the percentage of structural CA than the percentage of the numerical CA) and synergically induced the percentage of total CA when used as a mixture with MMC. The EE fruit juice did not affect the SCE frequency for 24 and 48 h treatment time. In contrast, EE and MMC as a mixture sinergically induced the SCE frequency at the highest concentration for 48 h treatment time only. EE alone did not decrease the RI while it decreased the MI in a dose-dependent manner. EE and MMC as a mixture have a higher cytotoxic effect than the cytotoxic effects of EE alone. As a result, it can be concluded that EE had no antimutagenic effect while EE had a mutagenic and a cytotoxic effect in human peripheral lymphocytes. This article was submitted by the authors in English.     

Complete mitochondrial genomes of Chionomys roberti and Chionomys nivalis (Mammalia: Rodentia) from Turkey: Insight into their phylogenetic position within Arvicolinae

Organisms Diversity & Evolution - The complete mitochondrial DNA (mitogenome) sequences of Chionomys nivalis and C. roberti were first presented as reference mitogenomes by the current study...     

Genetic and environmental influences on one-trial conditioned context aversion in mice

Anticipatory nausea (AN) is caused by an association between contextual cues and the experience of nausea (the side effects of chemotherapy or radiation treatment) and it develops predominantly in female patients undergoing chemotherapy. Preclinical studies in rodents show that the administration of an illness-inducing agent in the presence of novel contextual cues can cause conditioned context aversion (CCA) and this has been proposed to model AN. The literature also suggests that brief pre-exposure to a novel context prior to shock delivery is critical in the development of contextual fear conditioning in rodents (a phenomenon known as Immediate Shock Deficit), but this has not been assessed in CCA. The aim of present study was to develop a CCA paradigm to assess this in outbred (CD1) and inbred (C57BL/6J) mice and evaluate potential sex differences. The results revealed that a single conditioning trial in which a distinctive context was paired with LiCl-induced illness was sufficient to elicit a conditioned response in both female and male CD1 outbred mice, but not in C57BL/6J inbred mice. In addition, CCA was facilitated when animals had prior experience with the context. Finally, outbred female mice showed longer and more robust retention of CCA than male mice, which parallels clinical findings. The results indicate the importance of using CD1 outbred mice as an animal model of AN as well as examining sex differences in the CCA paradigm. Similar findings in humans encourage the future use of this novel CCA preclinical mouse model.     

Cold-induced genetic instability in micropropagated Pistacia lentiscus L. plantlets

Genetic stability of plants during in vitro propagation and conservation is one of the important aspects of plant biotechnology. In the present study, micropropagated P. lentiscus L. shoot cultures, which are cultivated for the mastic resin, have been cold stored up to 12 months at 4 °C in the dark for different durations (2, 4, 6, 8, 10 and 12 months) and genetic alterations in cold storage conditions were evaluated. Growth parameters such as proliferation rate, shoot numbers per explant, shoot lengths and shoot forming capacity were also calculated. Since the highest proliferation rate (100 %) was obtained in 6?month-stored shoot cultures without any severe influence of cold stress on proliferation ability, amplified fragment length polymorphism (AFLP) and inter-retrotransposon amplified polymorphism (IRAP) marker systems were used to determine genetic stability in the plantlets after this storage period. Totally, 702 scorable bands were produced by 10 AFLP primer pairs. Genetic similarity value of the non-stored (control) plant and cold-stored clones ranged from 0.66 to 0.84 with a mean of 0.74. In the case of IRAP, 159 bands were produced by 8 IRAP primers. Genetic similarity value of the non-stored plant and cold-stored clones varied from 0.65 to 0.83 and the average genetic similarity value was determined as 0.72. The genetic similarity indices revealed that genetic variability was similar in both techniques. Our results showed that tissue culture and especially cold storage of P. lentiscus L. may result transposons activation, thus could cause genetic instability.