Sevgi Durna Dastan

Investigation of acetylcholinesterase and mammalian DNA topoisomerases, carbonic anhydrase inhibition profiles, and cytotoxic activity of novel bis(α-aminoalkyl)phosphinic acid derivatives against human breast cancer

The aim of this study was to evaluate biologically active novel molecules having potentials to be drugs by their antitumor properties and by activities of apoptotic caspase and topoisomerase. Following syntheses of novel eight bis(α‐aminoalkyl)phosphinic acid derivatives (4a–h) as a result of array of reactions, compounds were evaluated by cytotoxic effects in vitro on human breast cancer (MCF‐7) and normal endothelial (HUVEC) cell lines. All phosphinic acid derivatives were effective for cytotoxicity on both MCF‐7 and HUVEC lines, while 4c, 4e, and 4f compounds were found significantly more effective. For the evaluation of antitumor properties of compounds in a highly sensitive method, their effects on inhibiting topoisomerases I and II were investigated. Also, some of the bis(α‐aminoalkyl)phosphinic acid derivatives (4a, 4e–h) showed nice inhibitory action against acetylcholinesterase and human carbonic anhydrase isoforms I and II.

Synthesis of some novel pyridine compounds containing bis-1,2,4-triazole/thiosemicarbazide moiety and investigation of their antioxidant properties, carbonic anhydrase, and acetylcholinesterase enzymes inhibition profiles

Some novel derivatives of thiosemicarbazide and 1,2,4‐triazole‐3‐thiol were synthesized and evaluated for their biological activities. The title compounds were prepared starting from readily available pyridine‐2,5‐dicarboxylic acid. The reaction carboxylic acid with absolute ethanol afforded the corresponding dimethyl pyridine‐2,5‐dicarboxylate (1). The reaction of dimethyl‐2,5‐pyridinedicarboxylate (1) with hydrazine hydrate good yielded pyridine‐2,5‐dicarbohydrazide (2). Refluxing compound 2 with alkyl/aryl isothiocyanate derivatives for 3–8 h afforded 1,4‐disubstituted thiosemicarbazides (3a–e). Base‐catalyzed intra‐molecular dehydrative cyclization of these intermediates furnished the 4,5‐disubstituted bis‐mercaptotriazoles (4a–e) in good yield (85%–95%). Among the target compounds, 2,2′‐(pyridine‐2,5‐diyldicarbonyl)bis[N‐(p‐methoxyphenyl)hydrazinecarbothioamide] (3c) showed very high activity with value of 72.93% against 1,1‐diphenyl‐2‐picrylhydrazyl free radical at the concentration of 25 μg/mL. The inhibitory effects of the target compounds against acetylcholinesterase (AChE), hCA I, and II were studied. AChE, cytosolic hCA I and II isoforms were potently inhibited by synthesized these derivatives with Kis in the range of 3.07 ± 0.76–87.26 ± 29.25 nM against AChE, in the range of 1.47 ± 0.37–10.06 ± 2.96 nM against hCA I, and in the range of 3.55 ± 0.57–7.66 ± 2.06 nM against hCA II, respectively.

Inhibitory effects of some drugs on carbonic anhydrase enzyme purified from Kangal Akkaraman sheep in Sivas, Turkey

In this study, carbonic anhydrase (CA) enzyme was purified and characterized from blood samples of Kangal Akkaraman sheep and inhibitory properties on certain antibiotics were examined. CA purification was composed of preparation of the hemolysate and conducting the Sepharose‐4B‐tyrosine‐sulfanilamide affinity gel chromatography in having specific activity of 11626 EU mg−1, yield of 14.40%, and 242.76‐fold purification. Sodium dodecyl sulfate‐polyacrylamide gel electrophoresis was performed to assess the enzyme purity and a single band was observed. Some antibiotics were exhibited in vitro inhibition on the CA activity. IC50 values of these inhibitors were calculated by plotting activity percentage. IC50 values of certain drugs (dexamethasone; caffeine; metamizole sodium; tetramisol; ceftiofur HCl; ivermectin; tavilin 50; penokain G; neosym; and sulfamezathine) were found as 0.38, 8.24, 285.53, 114.77, 5.33, 2.76, 27.58, 213.50, 208.28, and 36.60 μM, respectively. Ki values of different drugs on Kangal Akkaraman sheep blood CA activity were found in the range of 0.21 ± 0.038–266.64 ± 37.11 μM.

The effects of wireless electromagnetic fields on the activities of carbonic anhydrase and acetylcholinesterase enzymes in various tissues of rats

The purpose of our study is to assist in understanding the effects of wireless electromagnetic waves on carbonic anhydrase (CA) and acetylcholinesterase (AChE) enzymes activities in the different tissues of the rats. For this purpose, two different groups each of which contains eight rats (n = 8) were formed as being control group and wireless electromagnetic wave‐administered group. The rats were necropsied after 60 min from the injection of chemicals into the rats intraperitoneally. The different tissues of the rats were extracted. CA and AChE enzymes activities were measured for each tissue. All the experimental results were provided in mean ± S.D. Statistical significance was identified to be P < 0.05. It was observed that there were significant changes of enzyme activities in wireless‐administered group in salivary gland, stomach, colon, liver, and striated muscle tissues.

Synthesis and in vitro antioxidant evaluation of new bis(α-aminoalkyl)phosphinic acid derivatives

GRAPHICAL ABSTRACT ABSTRACT Diamines were added to arylaldehydes in ethanol, which resulted in corresponding diimines. Novel bis-1-aminophosphinic acid compounds were synthesized through the interaction of diimines and hypophosphorous acid. The new compounds were characterized by elemental analyses, FT-IR and 1H, 13C and 31P NMR techniques. The in vitro antioxidant activity of the newly synthesized compounds were measured and found to exhibit significantly higher antioxidant activity than the standard.

Evaluation of the antioxidant effects of melatonin on the larynx mucosa of rats exposed to environmental tobacco smoke.

This studys aim was to investigate the effect of melatonin in terms of mitigating the effects of smoking on the laryngeal mucosa of rats exposed to environmental tobacco smoke.

The effectiveness of platelet-rich plasma in an anosmia-induced mice model: PRP Treatment in Anosmic Mice

In this study, we aimed to functionally and morphologically demonstrate the effectiveness of platelet‐rich plasma (PRP) on anosmia in a mouse model of anosmia.