Band 40, Heft 3

Objective: The main objective of this study is to determine the methods used for dividing reference data into sub-groups and propose a new solution. Therefore, the newly proposed method is used to determine age sub-groups while calculating the reference interval of AST variable. Methods: The data of this study are composed of the registered patients who applied only once to the polyclinics at the Health Research and Application Hospital, Clinical Bio-Chemistry Laboratory of Mersin University. The main variables selected for the study are sex, age and aspartate transaminase (AST). MARS 2.0 package software was used for the statistical analysis. Harris&Boyd method was used for sex and age while the MARS method was used for the determination of age sub-groups. Results: According to the Harris&Boyd method, it was concluded that it is not necessary to create sub-groups for sex and age variables. Age sub-groups are determined with the MARS method by taking into account the correlations between AST variables and age. Age sub-groups are calculated as 5-9, 10-18 and 19+. Correlation between the age and AST variable is investigated for these sub-groups. It is obtained that the correlation is statistically not significant for the 5-9 age group (p=0.3189), significant for the 10-18 age group (p<0.001) and significant for 19 and above (p<0.001). Conclusion: The selection of transformation and outlier value elimination method and especially determination criteria for separation of sub-groups are made according to researcher’s subjective desicions in the application of many studies. Because of this reason, MARS can be used as an alternative and objective method for determining subgroups. In addition, results of MARS method being parallel with the findings of the producing company supported the usage of this method for determination of sub-groups.

Objective: Catechol-O-methyltransferase (COMT) is the key molecule in the catabolism of catecholamines like dopamine which is an important molecule in schizophrenia. Due to its function and location COMT gene is a strong candidate gene for schizophrenia. The aim of this study was to investigate the possible associations of 3 COMT single nucleotide polymorphisms (SNPs) and schizophrenia in our population. COMT enzyme activity is regulated by a widely known Val158Met polymorphism (rs4680), along with the variation of the SNPs rs737865 and rs165599. Methods: Val158Met polymorphism (rs4680), the SNPs rs737865 and rs165599 were the targets of this study. The study was performed with 96 patients (66 male and 30 female) and 100 controls (47 male and 53 female) from Malatya region on eastern part of Turkey by using TaqMan genotyping assays. Results: We couldn’t find a significant difference between the schizophrenia patients and normal controls for any of the SNPs that were studied. The genotype frequencies in both the patient and control groups satisfied the Hardy- Weinberg equilibrium. No significant gender differences were observed for the SNPs that were investigated. No significant difference was observed in the allele or genotype frequencies as well. Conclusion: COMT gene doesn’t appear to be a risk factor in this population of schizophrenia patients in Turkey.

Objective: This present investigation aimed at assessing the water quality of the Gediz River located in western Turkey. Methods: Some physicochemical parameters and nutrient concentrations of the surface water of Gediz River were determined over a period of twelve months (October to September 2012) at 5 sampling sites along the river. Results: Data on some ions namely NH 4 -N, NO 2 -N, NO 3 -N and PO-34-P were measured. The pH, temperature, electrical conductivity (EC), salinity and dissolved oxygen were also determined to assess the chemical status and pollution levels of the river. The measured data were given as mean, maximum, minimum values, respectively. In this context; the ranges for Water temperature [17.95°C±1.37ºC (30.2-4.5)], pH [7.45±0.06 (8.11-6.66)], Dissolved Oxygen [3.84±0.65 mg/L (6.25-2.43)], Electrical Conductivity (E.C) [1051.4±216.07 μS/cm (3000-296)], Salinity [0,16±0,05 ppt (0,8-0,1)], Ammonium nitrogen (NH 4 -N) [1.772±0.8228 mg/L (4.642-0.057)], Nitrite nitrogen (NO 2 -N) [0.605±0.4224 mg/L (2.312-0.050)], Nitrate nitrogen (NO3-N) [46.014±44.9878 mg/L (151.965-2.855)], Phosphate phosphorus (PO-34-P) [5.489±3.6356 mg/L (20.350-0.190)] were found to be higher than the natural background levels for surface water. Conclusion: This indicates pollution of the river water samples from the areas studied. Our findings highlighted the deterioration of water quality of the river due to anthropogenic and agriculturel activities.

Objective: Dipeptidyl peptidase IV (DPP IV) is a serine amino (exo) peptidase which regulates various processes most notably plasma glucose homeostasis by cleaving incretin peptide hormones as glucagon-like peptide-1 (GLP-1) and glucose-dependent insulin releasing polypeptide (GIP). Realization of the inhibition of this enzyme in controlling diabetes is one of the strategies adopted in recent years. The present study was designed to investigate the DPP IV inhibitory effects of sixteen plant having antidiabetic property in aqueous extracts in correlation with their protein content. Methods: In vitro DPP IV inhibition was evaluated by the specific inhibitory activity of plant aqueous extracts prepared without and with heat (60°C) treatment. Results: Among the tested plants Vitis vinifera L., Artemisia dracunculus L., Prunus laurocerasus L., Rubus caesius L. and Olea europaea L. extracts showed DPP IV inhibitory activity with respect to IC50 values of 0.04-0.09 mg protein/ml. Kinetic analysis indicated that the inhibitor potency of A. dracunculus extract was stronger than the other extracts. Conclusion: The present study is the first report on screening and preliminary characterization of DPP IV inhibitory activity in aqueous extracts of selected antidiabetic medicinal food. This study could provide a new insight into DPP IV inhibitors from plants that could be useful for treatment of Type 2 diabetes.

Objective: Quinones are highly reactive compounds undergoing either one- or two-electron reductions. Enzymatic one-electron reduction generates unstable semiquinone radicals which readily undergo redox cycling over NQO1 and NQO2 enzymes, in the presence of molecular oxygen, leading to the production of highly reactive oxygen species (ROS). NQO1 is responsible form detoxification where NQO2 inhibitors are found to show potent anticancerogenic effects. The aim of this study is to investigate some natural inhibitors of the NQO2 enzyme and to identify their action mechanisms over this enzyme on different cancer cell lines. Methods: First of all the NQO2 inihibitry effects of flavonoids were investigated over enzyme kinetix and Ki values were calculated. Then the cytotoxic effects of flavonoids on different cancer cell lines such as Jurkat Clone E-6, MCF7 and HepG2 cancer cell lines were investigated via MTT test and their effects on NQO2 protein expressions via western blotting. Results: Ki values for NQO2 inhibitory effects of the studied flavonoids are respectively, Apigenin (0.25 nM) <Kaempferol (0.55 nM) <Quercetin (1.06 nM) <Luteolin (1.54 nM). The IC50 values for flavonoids in three different cell lines were as follows: for Apigenin; 140 μM, 50 μM and 50 μM, for Kaempferol; 40 μM, 100 μM and 400 μM, for Quercetin; 10 μM, 60 μM and 50 μM, and for Luteolin; 50 μM, 60 μM and 75 μM in Jurkat Clone E-6, MCF7 and HepG2 cell lines, respectively. According to the western blotting results in Jurkat cell line, Apigenin; in MCF7, Kaempferol; significantly (p<0.05) reduced the NQO2 expression whereas in HepG2 cell lines any of them did not reveal any inhibitory effects. Conclusion: As a result, the tested flavonoids were all inhibitors of NQO2 enzyme in nM levels and in Jurkat and MCF7 cell lines the cytotoxic effects of Apigenin and Kaempferol have been associated with NQO2 inhibition.

Objective: Forskolin, an activator of adenylate cyclase and rolipram a selective inhibitor of phosphodiesterase 4, stimulate lipolysis and inhibit body weight increase by increasing cyclic adenosine monophosphate (cAMP) levels. This study was aimed to investigate the effects of them on leptin, resistin and adiponectin levels in diet induced obesity in rats. Methods: Totally 50 rats were randomly divided into five groups. The Group I was fed with standard pellet diet and the other groups were fed with high-fat diet for 10 weeks. During the last two weeks of the study, group II continued to fed with high-fat diet whereas group III, group IV and group V were administered forskolin, rolipram and forskolin plus rolipram respectively by orogastric tube in addition to their high-fat diet. Then, rats were sacrificed and serum leptin, resistin and adiponectin levels were measured. Results: Although adiponectin levels of group II (p<0.001 for adiponectin, p<0.01 for leptin), group III (p<0.01), group V (p<0.05) were significantly decreased, leptin levels were significantly increased compared to that of the group I. Also, leptin levels of group IV were significantly reduced compared to those of group II (p<0.05). There were no significant differences between resistin levels of the groups. Conclusion: Our results showed that rolipram prevented any alteration in the levels of leptin and adiponectin in addition to its effect on cAMP levels. However, forskolin and rolipram showed no effect on resistin levels of the groups. The underlying mechanism of these findings is not known and needs to be more investigated.

Objective: The purpose of this study is to demonstrate protective effects of walnut samples on CCl 4 - induced tissue damage in vivo. Methods: Walnut fruits were extracted and then subjected to vitamin and flavonoid analyses. The extracts obtained were injected intraperitoneally every other day to Wistar male rats given carbon tetrachloride (CCl 4 ) and the animals were decapitated at the end of the study period. The brain, kidney, and liver tissues were removed and lipid peroxidation (LPO) measurements were done in the lipid fraction generated. The fatty acids in the lipid extract were analyzed by gas chromatography after converting them into methyl esters. In addition, the amounts of glutathione, protein, and vitamins were analyzed. Results: Given the results achieved, it was found that the levels of fatty acids increased in the brain and kidney tissues after CCl 4 administration (p<0.001). In the groups given walnut extract against CCl 4 , it was found that the glutathione (GSH) level increased and malondialdehyde (MDA) level reduced in all tissues (p<0.05, p<0.01). Given lipophilic vitamin levels, it was found that α-tocopherol level increased in the brain and liver tissues in the group receiving additional walnut in comparison with the controls (p<0.05), and cholesterol level increased in the tissues, except kidney, in all groups in comparison with the control group (p<0.05, p<0.001). Conclusion: Our data indicates that walnut extract has protective effects against LPO formation in the brain, kidney and liver tissues.

Objective: Glutathione S-transferase (GST) and NAD(P)H:quinine oxidoreductase 1 (NQO1) are the enzymes important in cytoprotection and bioactivation of chemicals. This study has addressed effects of polyphenolic compounds; ellagic acid, quercetin, naringenin, resveratrol, rutin and hesperidin on rabbit liver GST and NQO1 enzyme activities. Methods: Cytosolic fractions were obtained from homogenized liver tissues of rabbit by differential centrifugation. After calculating IC 50 values of individual enzymes for phenolic compounds, both Lineweaver-Burk and Dixon plots were drawn to determine the effect of phenolics on enzyme activity. Michaelis-Menten constant (K m ), maximum velocity (V max ), and inhibition constant (K i ) were calculated from Lineweaver-Burk and Dixon plots, respectively. Results: Resveratrol was found to be the most potent inhibitor for rabbit hepatic cytosolic GST activity with 75.9±2.06 μM IC 50 value while naringenin was the least potent one with IC 50 value of 260±1.92 μM. Hesperidin and quercetin were found to be the most and least potent inhibitors for NQO1 enzyme activity with IC 50 values of 2.7±0.85 μM and 13.8±0.91 μM, respectively. Resveratrol and naringenin inhibited GST activity noncompetitively and mixed type with K i of 6.2 μM and 245 μM, respectively; while both hesperidin with 0.64 μM K i value and quercetin with 3.5 μM K i value inhibited NQO1 activity in a competitive manner. Conclusion: These results indicate that phenolic compounds may modulate Phase II enzyme, GST and NQO1. Moreover, they can influence the metabolic activation of xenobiotic and toxic compounds metabolized by this enzyme.

Objective: Our aim was to determine whether cystatin C level has a superiority to creatinine to assess kidney functions in rapid decreases of glomerular filtration rate due to acute mercury exposure in children. Eight different glomerular filtration rate calculation formulas which have been used creatinine and/or cystatin C were also compared. Methods: Serum urea, creatinine and cystatin C values of 39 mercury exposed children were measured. Glomerular filtration rates were calculated by eight different formulas. Patient group was divided into three subgroups according to mercury levels. Results: Cystatin C and mercury levels of the patients were found significantly different from control group (p<0.001). There was not a significant difference in creatinine and urea values between two groups (p=0.913, p=0.236). There was not a significant difference between patient and control groups in GFR calculations which have been used serum creatinine and height or which have been used urea additional to them (p=0.069, p=0.559, p=0.424, p=0.945, respectively), but there was a significant difference between patient and control groups in GFR calculations which have been used cystatin C only or creatinine, urea and height in addition to this (p<0.001, p<0.001, p=0.042, p<0.001, respectively). In sugroup analysis, cystatin C results and the results of three GFR calculations of four GFR calculations which were used cystatin C were found different in control group according to subgroups but there was not a difference between subgroups. Conclusion: Cystatin C level is a better indicator than creatinine to assess kidney functions in rapid decreases of glomerular filtration rate due to acute exposure of mercury. Formulas using cystatin C gave better results than formulas using creatinine and height in estimation of glomerular filtration rate.

Objective: Three plasmids from Lactobacillus paracasei 54 were isolated from healthy newborn infant fecal samples. Methods: Plasmid was extracted using an AxyPrep Plasmid Miniprep Kit and lysozyme. The extracted plasmids were sequenced using a Roche 454 Genome Sequencer FLX. Results: Three plasmids were isolated from Lactobacillus paracasei 54. These plasmids are designated pLP5401- 03, and they are 9754, 6650, and 1788 bp in size. Conclusion: Plasmids pLP5401 and pLP5402 were found to contain replication genes that are likely to function via the theta-type mechanism. Plasmid pLP5403 is predicted to replicate via the rolling-circle replication (RCR) mechanism. The RCR replication plasmid can be applied as a useful vector in the food industry