Effects of Continuous and Intermittent Magnetic Fields on Oxidative Parameters In vivo

Continuous and intermittent 50 Hz, 1.5 mT magnetic field with the exposure period of 4 h/day for 4 days was used to investigate its possible effect on adult guinea pigs. Tissues and plasma specimens were assessed by biochemical parameters. Malondialdehyde (MDA), glutathione (GSH), nitric oxide (NO) levels and myeloperoxidase activity (MPO) were examined in plasma, liver and brain tissues. All parameters were determined by spectrophotometer. While intermittent magnetic field was effective on plasma lipid peroxidation, continuous magnetic field was found to be effective on plasma MPO activity and NO levels. Augmentation of lipid peroxidation was also observed in liver tissue both intermittent and continuous magnetic field exposures. These results indicate that both the intermittent and continuous magnetic field exposures affect various tissues in a distinct manner because of having different tissue antioxidant status and responses.     

Genetic alterations in gastric precancerous lesions

To investigate the occurrence of 17p (p53) loss of heterozygosity (LOH) and increased 4N or aneuploidy in gastric precancerous lesions (GPL), and their association with Helicobacter pylori (H pylori) infection. A total of 78 gastric mucosal biopsy specimens, including 10 normal mucosa and 68 gastric precancerous lesions [chronic atrophic gastritis (CAG, n = 20), intestinal metaplasia (IM, n = 12), low grade dysplasia (LGD, n = 15), and high grade dysplasia (HGD, n = 21)] were studied using PCR and flow cytometry. A modified Giemsa staining technique was used to detect H pylori. The study was performed in Erzurum Numune Hospital between 2007 and 2009. 17p (p53) LOH was observed in (1/20) 5% of CAG, in (2/12) 16% of IM, in (3/15) 20% of LGD and in (11/21) 53% of HGD. There was correlation between prevalence of 17p (p53) LOH and histological type of GPL (P = 0.004). Similarly, increased 4N or aneuploidy was detected in (1/20) 5% of CAG, in (1/12) 8% of IM, in (2/15) 13% of LGD and in (9/21) 43% of HGD. The correlation was found between aneuploidy and histological type of GPL (P = 0.009). However, there was no correlation between presence of H pylori infection in histological type of GPL (P = 0.921). On the other hand, a significant association was found between increased 4N or aneuploidy and 17p (p53) LOH in all of GPL (P = 0.0001). However, there was no statistically significant association between H pylori infection and 17p (p53) LOH or increased 4N/aneuplody in GPL. 17p (p53) LOH and increased 4N or aneuploidy are closely related to the early stages of gastric carcinogenesis.     

Wide-Inhibitory Spectra Bacteriocins Produced by Lactobacillus gasseri K7

The aim of our study was to determine the genetic characterization and classification of Lb. gasseri K7 bacteriocins, comparison with bacteriocins of the Lb. gasseri LF221 strain and other related strains. Bacteriocin-encoding genes were amplified by PCR, subjected to DNA sequencing, and BLAST sequence analysis was performed to search the database for homologous peptides. Lb. gasseri K7 produces two two-peptide bacteriocins, named gassericin K7 A and gassericin K7 B. Their nucleotide sequences were deposited at GenBank, under accession numbers EF392861 for the gassericin K7 A and AY307382 for the gassericin K7 B. Analysis of gene clusters of bacteriocins in Lb. gasseri K7 strain revealed a 100 percent sequence identity with bacteriocins in LF221 strain. An active peptide of gassericin K7 B is homologous to the complementary peptide of gassericin T, and a complementary peptide of gassericin K7 B is homologous to the active peptide of gassericin T. Another surprising finding was that the sakacin T-beta peptide is partly homologous to the active peptide of gassericin K7 A, while the other sakacin T peptide (alfa) is partly homologous to the complementary peptide of gassericin K7 B. Gassericins of Lb. gasseri K7 strain were both classified as two-peptide bacteriocins. Human probiotic strains Lb. gasseri K7 and LF221 are different isolates but with identical bacteriocin genes. They produce wide-inhibitory spectra bacteriocins that are new members of two-peptide bacteriocins with some homologies to other bacteriocins in this group. Described bacteriocins offer a great potential in applications in food industry, pharmacy and biomedicine.     

Genotoxic action of fungicide Conan 5FL (hexaconazole) on mammalian cells in vivo and in vitro

The genotoxic effects of fungicide Conan 5FL (containing 50 g/L hexaconazole) in mouse bone-marrow cells and human lymphocytes have been evaluated. Three different concentrations of Conan 5FL (17.50, 35.00 and 70.00 microg/mL for human lymphocytes and 17.50, 35.00 and 70.00 mg/kg for mouse bone marrow cells) were studied. Conan 5FL induced significant increases (except 17.50 mg/kg for mouse bone marrow) in the frequency of chromosomal aberrations (CAs) in both test systems. This fungicide caused structural and numerical abnormalities in both mammalian cells. These are sister chromatid union, chromatid and chromosome breaks, fragments, dicentric and ring chromosomes, and polyploidy. Significant increase was found in induction and in minimum-maximum numbers of sister chromatid exchanges (SCEs) at all treatments compared with the negative control. Conan 5FL did not affect the replication index (RI) in human lymphocyte cultures, however, it significantly decreased the mitotic index (MI) in all treatment concentrations in both test systems. Using of Conan 5FL should be reconsidered due to its possible cytotoxic, clastogenic and mutagenic effects.     

Resistance outside the substrate envelope: hepatitis C NS3/4A protease inhibitors

Direct acting antivirals have dramatically increased the efficacy and tolerability of hepatitis C treatment, but drug resistance has emerged with some of these inhibitors, including nonstructural protein 3/4?A protease inhibitors (PIs). Although many co-crystal structures of PIs with the NS3/4A protease have been reported, a systematic review of these crystal structures in the context of the rapidly emerging drug resistance especially for early PIs has not been performed. To provide a framework for designing better inhibitors with higher barriers to resistance, we performed a quantitative structural analysis using co-crystal structures and models of HCV NS3/4A protease in complex with natural substrates and inhibitors. By comparing substrate structural motifs and active site interactions with inhibitor recognition, we observed that the selection of drug resistance mutations correlates with how inhibitors deviate from viral substrates in molecular recognition. Based on this observation, we conclude that guiding the design process with native substrate recognition features is likely to lead to more robust small molecule inhibitors with decreased susceptibility to resistance.     

Effects of dietary protein and lipid levels on growth and feed utilization of wild‐caught striped sea bream,Lithognathus mormyrus

A feeding trial was carried out to determine the effects of dietary protein and lipid levels on the growth performance and feed utilization of wild‐caught striped sea bream (Lithognathus mormyrus). The experimental fish were collected from a local lagoon (Çardak Lagoon, Çanakkale, Turkey), transferred to the Marine Net Cage Unit and fed by hand to apparent satiation with a commercial sea bream feed (Biomar; 42% crude protein, 16% crude lipid). Approximately 4 weeks were needed to acclimate the fish to farming conditions. No pathological signs were observed and no fish losses occurred during the adaptation period. For the test trials four test diets with different levels of protein and lipid were formulated [low protein and low lipid (LP:LL), low protein and high lipid (LP:HL), high protein and low lipid (HP:LL), and high protein and high lipid (HP:HL)] and fed to L. mormyrus (mean weight 85.0 ± 4.6 g SEM) in the net cages (Ø 2 m, depth 2.5 m) for 60 days. During the experiment water temperature varied between 21.1 and 26.4°C; dissolved oxygen 8.4–9.6 mg L^?1; pH 7.2–8.6; and salinity 23.3–25.6‰. Growth performances of fish fed high protein diets were higher compared to fish fed low protein diets, irrespective of the dietary lipid level (P < 0.05). Feed conversion ratio (FCR) and protein efficiency ratio (PER) were not influenced by dietary protein or lipid levels (P > 0.05). Preliminary results indicate that striped sea bream can be easily adapted to farming conditions in net cages, and that a diet containing 50% crude protein and 15% crude lipid (HP:LL) levels with 23.0 g protein MJ^?1 gross energy of protein/energy ratio would be suitable for striped sea bream growth.     

Concentrations of some major and minor elements in larynx tissues with and without cancer

In this study, concentrations of some major and minor elements were determined in the larynx tissues with and without cancer, and results obtained were statistically compared. No meaningful differences were found between sodium, potassium, calcium and copper concentrations in cancer tissues, corresponding cancer-free adjacent tissues and in control larynx tissues. Phosphate concentrations of the cancer tissues were higher compared with cancer-free adjacent tissues and control tissues. Iron, zinc and magnesium concentrations were found increased in both cancer and corresponding cancer-free adjacent tissues relative to control values. Intra- and inter-element correlations established within and between groups indicated that relations between elements were also disordered in the cancer tissues. We suggest that the changed element status of cancerous larynx tissues may arise from increased requirements of cancer tissues for some elements such as iron, zinc, magnesium and phosphate.     

Screening of antimicrobial,antioxidant, antidiabetic activities,anatomical and morphological properties of Colchicum speciosum Steven (Colchicaceae)

Protoplasma - Colchicum speciosum Steven species is a perennial stemless plant. C. speciosum is a flowering herb native to mountainous regions of northern Turkey, the Caucasus, and northern Iran....     

Antimicrobial Activity and Mechanism of Essential Oil of Endemic Salvia hypargeia Finc. & Mey. in Turkey

In this study, the aerial parts of Salvia hypargeia were subjected to hydrodistillation and the resulting compounds were analyzed in GC–MS. Antimicrobial activity of S. hypargeia essential oil (EO) against A. baumannii, S. aureus, and C. tropicalis were determined by agar well diffusion assay and microdilution method. Antimicrobial mechanism of the EO were investigated based on change of TTC-dehydrogenase relative, leakages of intracellular protein, DNA and potassium ion (K +). The main components of the EO were β-pinene, 1,8-cineole, camphor, α-pinene, 4-terpineol, and 4-thujanol. The MICs of the EO against the microorganisms were 15.2 mg/mL for S. aureus, 17.5 mg/mL for C. tropicalis and 28.8 mg/mL for A. baumannii. The inhibition zones were 18.16 mm, 25.01 mm, and 27.01 mm for A. baumannii, S. aureus, and C. tropicalis, respectively (p < 0.05). An increase in DNA, protein and K⁺ leakage was observed when microorganisms were exposed to the EO. The TTC-DRA of the treated microorganism cells was also significantly decreased because of slowing the respiration. The present study provided an experimental basis of practical application of S. hypargeia EO as a natural agent.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12088-021-00939-1.