Evaluation of chalcones as inhibitors of glutathione S‐transferase

Glutathione S‐transferases (GSTs) are the superfamily of multifunctional detoxification isoenzymes and play an important role in cellular signaling. In the present study, potential inhibition effects of chalcones were tested against human GST. For this purpose, GST was purified from human erythrocytes with 5.381 EU?mg^?1 specific activity and 51.95% yield using a GSH–agarose affinity chromatographic method. The effects of chalcones on in vitro GST activity were tested at various concentrations. K_i constants of chalcones were found in the range of 7.76–41.93 μM. According to the results, 4‐fluorochalcone showed a better inhibitory effect compared with the other compounds. The inhibition mechanisms of 2'‐hydroxy‐4‐methoxychalcone and 4‐methoxychalcone were noncompetitive, whereas the inhibition mechanisms of 4'‐ hydroxychalcone, 4‐ fluorochalcone, and 4,4'‐ diflurochalcone were competitive.     

Trace Metal Levels in Rainbow Trout (Oncorhynchus mykiss) Cultured in Net Cages in a Reservoir and Evaluation of Human Health Risks from Consumption

Although fish consumption has positive health effects, metals accumulated in fish can cause human health risks. In this study, the levels of ten metals in rainbow trout (Oncorhynchus mykiss) farmed in the Keban Dam Reservoir, which has the biggest rainbow trout production capacity in Turkey, were determined and compared with the maximum permissible levels (MPLs). Also, human health risks associated with rainbow trout consumption were assessed. The metal concentrations in rainbow trout were found below the MPLs. The estimated daily intake of each metal was much lower than the respective tolerable daily intake. The target hazard quotient (THQ) for individual metal and total THQ for combined metals did not exceed 1, indicating no health risk for consumers. The cancer risk (CR) value for inorganic arsenic was within the acceptable lifetime risk range of 10⁻⁶ and 10⁻⁴. For carcinogenic and non-carcinogenic effects, the maximum allowable fish consumption rates were high enough to ensure the human health. According to these results, the consumption of rainbow trout farmed in the Keban Dam Reservoir does not pose a risk on human health.

     

Effects of eCG and FSH on ovarian response, recovery rate and number and quality of oocytes obtained by ovum pick-up in Holstein cows

The goal of the present study was to compare the ovarian response, oocyte yields per animal, and the morphological quality of oocytes collected by ultrasound guided follicular aspiration from Holstein cows treated either with FSH or eCG. Twenty four normal cyclic, German Holstein cows were randomly divided into two groups. Fourteen cows received 3000 IU eCG on day-4 prior to ovum pick-up (OPU) (day 0), 2 days later (day-2), 625 microg cloprostenol was administered. On day-1 GnRH was administered i.m. and 24h later OPU (day 0) was performed. In ten cows a total dose of 500 IU follicle stimulating hormone (Pluset) was administered intramuscularly in a constant dosage for 4 days with intervals of 12h, starting on day-5. Luteolysis was induced by application of 625 microg cloprostenol on day-2. On day-1 (24h after the last FSH treatment) GnRH was administered i.m. and 24h later OPU (day 0) was performed. Ovarian follicles were visualized on the ultrasound monitor, counted and recorded. All visible antral follicles were punctured. Recovered oocytes were graded morphologically based on the cumulus investment. Average follicle number in ovaries was higher in FSH group than eCG group (p<0.05). Oocyte yields per animal did not differ between FSH and eCG groups. The proportion of grade A oocytes was higher in the FSH group in the than eCG group (p<0.05). Likewise, rate of grade C oocytes in FSH group were lower than eCG group (p<0.05). In conclusion, these results suggest that ovarian response, follicle number in ovaries and oocyte quality are affected by the type of gonadotropin and FSH is better alternative than eCG for OPU treatment.     

A hybrid risk-based approach for maritime applications: The case of ballast tank maintenance

Risk assessment is vital for cost-effective ship management in maritime industry since numerous maritime activities pose potential hazards according to the human causalities. Therefore, safety practitioners attempt to offer proactive approaches to mitigate risk as much as possible. In this context, this article presents a hybrid risk-based approach for maritime industry by adopting Fuzzy Analytic Hierarchy Process (FAHP) with fuzzy VIKOR (FVIKOR) methods under Fine-Kinney approach. To illustrate the hybrid risk-based approach, ballast tank maintenance process is handled since there are various hazards causing fatalities, severe injuries, and illness during ballast tank maintenance procedure than any other type of shipboard work. An extensive risk analysis is performed to enhance environment safety and operational reliability in maritime industry. Besides its theoretical contribution, the outcomes of the paper contribute to improve overall safety level of ship by considering potential hazards in risk management.     

Expression of novel cytosolic malate dehydrogenases (cMDH) in Lupinus angustifolius nodules during phosphorus starvation

During P deficiency, the increased activity of malate dehydrogenase (MDH, EC 1.1.1.37) can lead to malate accumulation. Cytosolic- and nodule-enhanced MDH (cMDH and neMDH, respectively) are known isoforms, which contribute to MDH activity in root nodules. The aim of this study was to investigate the role of the cMDH isoforms in nodule malate supply under P deficiency. Nodulated lupins (Lupinus angustifolius var. Tanjil) were hydroponically grown at adequate P (+P) or low P (−P). Total P concentration in nodules decreased under P deficiency, which coincided with an increase in total MDH activity. A consequence of higher MDH activity was the enhanced accumulation of malate derived from dark CO₂ fixation via PEPC and not from pyruvate. Although no measurable neMDH presence could be detected via PCR, gene-specific primers detected two 1 kb amplicons of cMDH, designated LangMDH1 (corresponding to +P, HQ690186) and LangMDH2 (corresponding to −P, HQ690187), respectively. Sequencing analyses of these cMDH amplicons showed them to be 96% identical on an amino acid level. There was a high degree of diversification between proteins detected in this study and other known MDH proteins, particularly those from other leguminous plants. Enhanced malate synthesis in P-deficient nodules was achieved via increased anaplerotic CO₂ fixation and subsequent higher MDH activities. Novel isoforms of cytosolic MDH may be involved, as shown by gene expression of specific genes under P deficiency.     

Frequency of MEFV gene mutations in Hatay province,Mediterranean region of Turkey and report of a novel missense mutation (I247V)

In the present study, 1000 patients with clinical suspicion of FMF were retrospectively reviewed to determine the spectrum of MEFV gene mutations by using DNA sequence analysis between September, 2008 and April, 2012. Sixteen different mutations and 55 different genotypes were detected in 618 of 1000 patients. Among 16 different mutations, R202Q (21.35%) was the most frequently observed mutation; followed by E148Q (8.85%), M694V (7.95%), M680I (2.40%), V726A (1.85%), M694I (0.95%), A744S (0.80%), R761H (0.55%), P283L (0.35%), K695R (0.20%), E230K (0.15%), L110P (0.10%), I247V (0.05%), G196W (0.05%) and G304R (0.05%). In the present study, a novel missense mutation (I247V) and a silent variant (G150G) were identified in the MEFV gene. On the other hand, P238L, G632A and G304R mutations are the first cases reported from Turkey. Our results indicated that MEFV mutations are highly heterogeneous in our study population as in other regions of Turkey and mutation screening techniques such as PCR-RFLP, amplification refractory mutation system or reverse hybridization do not adequately detect uncommon or novel mutations. Therefore, it was proven that sequence analysis of the MEFV gene could be useful for detection of rare or unknown mutations.     

Synthesis and carbonic anhydrase I,II, IV and XII inhibitory properties of N-protected amino acid – sulfonamide conjugates

N-protected amino acids (Gly, Ala and Phe protected with Boc and Z groups) were reacted with sulfonamide derivatives, leading to the corresponding N-protected amino acid–sulfonamide conjugates. The carbonic anhydrase (CA, EC 4.2.1.1) inhibitory activity of the new compounds was assessed against four human (h) isoforms, hCA I, hCA II, hCA IV and hCA XII. Among them, hCA II, IV and XII are antiglaucoma drug targets, being involved in aqueous humor secretion within the eye. Low nanomolar inhibition was measured against all four isoforms with the 20 reported sulfonamides, but no selective inhibitory profiles, except for some CA XII-selective derivatives, were observed. hCA I, II and XII were generally better inhibited by sulfonamides incorporating longer scaffolds and Gly/Ala, whereas the best hCA IV inhibitors were homosulfanilamide derivatives, incorporating Phe moieties. The amino acid–sulfonamide conjugates show good water solubility and effective hCA II, IV and XII inhibition, and may be considered as interesting candidates for antiglaucoma studies.     

The inhibitory effects of phenolic Mannich bases on carbonic anhydrase I and II isoenzymes

Phenolic mono Mannich bases [2-[4-hydroxy-3-(aminomethyl)benzylidene]-2,3-dihydro-1H-inden-1-one (8–15)] and bis Mannich bases [2-[4-hydroxy-3,5-bis(aminomethyl)benzylidene]-2, 3-dihydro-1H-inden-1-one (2–7)] were synthesized starting from 2-(4-hydroxybenzylidene)-2, 3-dihydro-inden-1-one (1). This study was designed in order to investigate the carbonic anhydrase (CA, EC 4.2.1.1) inhibitory properties of a library of compounds incorporating the phenol functional group. All prepared compounds showed a low inhibition percentages on both human (h) isoforms hCA I and hCA II compared to the reference sulfonamide acetazolamide. Mannich bases 2–15 had lower inhibition percentages than the compound 1 on hCA I and hCA II, except compound 14, which is a Mannich base derivative of dipropylamine, which had a similar inhibitory power as compound 1 on hCA II. All compounds synthesized 1–15 were 1.3–1.9 times more effective on hCA II comparing with the effectivenes of the compounds on hCA I.     

Actin--an inhibitor of eukaryotic elongation factor activities

An inhibitor of diphtheria toxin- and endogenous transferase-dependent ADP-ribosylation of eukaryotic elongation factor 2 (eEF2) has been found in the cytoplasmic fraction from rat liver. We provide evidence that this cytoplasmic inhibitor corresponds to actin, which gives rise also to inhibition of polyphenylalanine (polyPhe) synthesis. Both globular monomeric (G-actin) and filamentous (F-actin) forms of actin appear to be inhibitory on the action of elongation factors 1 and 2 (eEF1 and eEF2) in polyPhe synthesis with the inhibitory effect of G-actin proving to be stronger. Some component(s) in the postribosomal supernatant (S-130) fraction and also DNase I prevent actin-promoted inhibition of polyPhe synthesis.