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Retigabine (RTG, Ezogabine, DC23129) is the first neuronal potassium channel opener in the treatment of epilepsy and exerts its effects through the activation of neuronal KCNQ2/3 potassium channels; in higher doses, it acts also on sodium and voltage-gated calcium channels. The aim of this study was to investigate possible age-dependent therapeutic effects of RTG on spike-and-wave discharges (SWD) in an animal model of absence epilepsy using WAG/Rij rats. In this study, 6- and 12-month-old WAG/Rij rats were used. For both age categories, three sub-groups that consisted of one control group (n=7) by the administration of 20% DMSO (control) and two study groups by the administration of 5 mg/kg (n=7) and 15 mg/kg RTG (n=7) were designed. EEG electrodes were placed onto the skull of anaesthetized animals; and baseline EEG was recorded for one hour after a recovery period from surgery. Then, the pre-determined two distinct doses of RTG and 20% DMSO were administered as a solvent via intraperitoneal injections, and EEG was recorded for 3 hours. After injection, both doses of RTG increased the total SWD number and duration of SWD in the first and second hours in 12-month-old rats. These parameters were elevated compared to 6-month-old rats. Age-dependent effects of RTG were observed in SWD activity. Pro-epileptic effects in middle-aged WAG/Rij rats were demonstrated in both RTG doses. Differences in the distribution of KCNQ2/3 channels and switch of GABAergic system from inhibitory to excitatory with age might contribute to increased SWD activity in middle-aged rats.

Aim: This study was carried out to investigate the changes in muscle contraction parameters after very heavy exercise in professional football players with Tensiomyography, which is a non-invasive method. Method: Professional licensed football players in the A team of the team they play in the Turkish Super League (n = 11), whose age is 27.27 ± 1.55 years, weight is 74.82 ± 1.83kg, and height is 178.1 ± 1.76cm. participated. Tensiomyography measurements are bilateral m. The first measurement was taken from the rectus femoris muscle before heavy exercise (MET = 11) and the second measurement after it. In the measurements made, the muscle; Contraction time (Tc), maintenance time (Ts), relaxation time (Tr), displacement (Dm), lag time (Td) and contraction velocity (Vc) were evaluated. GraphPad Prism 9.0 program was used to analyze the data. Results: In the measurements made, a statistically significant decrease was observed in Dm, Td and Vc values in the right and left extremities compared to the 1st and 2nd measurements (p

Objective: The aim of this study was to investigate changes in natural killer (NK) cell proportion, NK cell activity, and cytokine levels in children with acute lymphoblastic leukemia (ALL) during and after therapy. Materials and Methods: The study group included 33 ALL patients and the control group consisted of 11 healthy children. The ALL patients were divided into three groups, those who had completed protocol M, receiving maintenance chemotherapy, and whose chemotherapy was discontinued. NK cell cytotoxicity was evaluated at different effector to target (E:T) cell ratios and in lytic units (LU). Expression of CD56, CD3, NKp46, CD2, CD94, NKG2D, and CD16 molecules and levels of the interferon gamma (IFN-γ) and interleukin-15 (IL-15) were measured. Results: NK cell activity at an E:T ratio of 1:1 was higher in patients receiving maintenance chemotherapy compared to the other groups (p0.05). The ratio of CD16+CD56+ cells was smaller in the maintenance chemotherapy group compared to controls (p, Amaç: Bu çalışmanın amacı, akut lenfoblastik lösemili (ALL) çocuklarda tedavi sırasında ve sonrasında doğal öldürücü (NK) hücre oranı, NK hücre aktivitesi ve sitokin düzeylerindeki değişiklikleri araştırmaktır. Gereç ve Yöntem: Çalışma grubu 33 ALL hastasını ve kontrol grubu 11 sağlıklı çocuktan oluştu. ALL hastaları, M protokolünü tamamlayan, idame kemoterapisi alan ve kemoterapisi kesilen olmak üzere üç gruba ayrıldı. NK hücre sitotoksisitesi, farklı efektör-hedef (E:H) hücre oranlarında ve litik birimlerde (LU) değerlendirildi. CD56, CD3, NKp46, CD2, CD94, NKG2D ve CD16 moleküllerinin ekspresyonu ve interferon gamma (IFN-γ) ve interlökin-15 (IL-15) seviyeleri ölçüldü. Bulgular: 1:1 E:H oranında NK hücre aktivitesi idame kemoterapisi alan hastalarda diğer gruplara göre daha yüksek (p0.05). CD16+CD56+ hücrelerin oranı, kontrollere göre idame kemoterapi grubunda daha düşük (p

Epilepsy is a major pathological condition, characterized by recurrent seizures and affecting approximately 1% of the population. Many studies have shown a relationship between epilepsy and inflammation. The adenosinergic system contributes to inflammation and epilepsy by regulating the release of neurotransmitters through its various receptors. This study investigates the effect of agonist and antagonist of adenosinergic system on seizure activity and cytokine levels in the WAG/Rij strain, a genetic animal model of absence epilepsy. The WAG/Rij rats used in our study were assigned to saline, Tween 20, adenosine, and caffeine groups. Tripolar electrodes were implanted on the skull, and EEG activities recorded for 3 h. ELISA was used to determine the NFkB, TNF-α, IL-1β, and IL-6 levels in the cortical and thalamic brain regions, as well as the TNF-α, IL-1β, and IL-6 levels in the blood samples. Administration of caffeine to rats resulted in a decreased SWD number at 30 and 60 min as determined by EEG recording after baseline (p .05), and a significant increase in NFkB and IL-6 levels in the thalamic tissue (p .05). Administration of adenosine to rats did not change seizures and cytokine levels. Our results show that an increase in thalamic IL-6 and NFkB levels may related with a decrement in absence epilepsy. This study clearly shows the contribution of adenosinergic system in absence seizure in WAG/Rij rats. These results also support the importance of the thalamus on occurrence of SWD in the thalamocortical loop.

The study was supported by Istanbul University Scientific Research Projects (Project Number: 4561)., The blood-brain barrier (BBB), which saves the brain from toxic substances, is formed by endothelial cells. It is mainly composed of tight junction (TJ) proteins existing between endothelial cells. Estrogen is an important regulatory hormone of BBB permeability. It protects the BBB before menopause, but may increase BBB permeability with aging. In addition, nitric oxide modulates BBB permeability. Alcohol impairs the integrity of the BBB with oxidants and inflammatory mediators such as iNOS. We investigated the effects of estrogen on BBB integrity in an in vitro BBB model created with ER alpha-free HUVEC (human umbilical vein endothelial-like cells) to mimics the menopausal period. In vitro BBB model is created with HUVEC/C6 (rat glioma cells) co-culture. The effect of 17 beta-estradiol on ethanol-induced BBB disruption and change/or increase of iNOS activity, which modulate BBB integrity, were evaluated. Inducibility and functionality of BBB were investigated using transendothelial electrical resistance (TEER) and the expression of proteins TJ proteins (occludin and claudin-1) and iNOS activity by immunostaining. Our results revealed that 17 beta-estradiol treatment before and after ethanol decrease expression of occludin and claudin-1 and value of TEER which are BBB disrupt indicators. In addition, ethanol and 17 beta-estradiol separately and pre-and post-ethanol 17 beta-estradiol treatment increased iNOS expression. Thus our study suggests caution in the use of 17 beta-estradiol after menopause because 17 beta-estradiol at this time may both increase the inflammatory process as well as damage the BBB. We think that beneficial effects of 17 beta-estradiol may be through ER alpha but it needs further studies., Istanbul University Scientific Research Projects [4561]

Objective: It has been suggested that the adenosinergic system and cytokines play a role in the pathogenesis of epilepsy. Although the role of the adenosinergic system in the modulation of seizure activity is well known, the mechanism of this modulation needs to be described in detail. We performed this study to determine the contribution of the proinflammatory cytokines to the generalized seizure activity during adenosine and caffeine treatment. Methods: We induced generalized tonic-clonic seizures with the administration of 60 mg/kg pentylenetetrazole (PTZ) in male Wistar Albino rats. Adenosine (500 mg/kg) or caffeine (5 mg/kg) was administered before PTZ injection. We monitored seizure activity and then determined the TNF-α, IL-1β, and IL-6 levels in the cortical and thalamic brain regions of rats by ELISA. Results: Adenosine pretreatment significantly extended seizure latency (p < 0.05), but did not affect seizure duration and entry time to stage 4 seizure. Caffeine pretreatment did not change seizure latency and seizure duration. PTZ treatment did not change brain cytokine levels significantly (p > 0.05) compared to the control group. Whereas adenosine pretreatment decreased brain TNF-α, IL-1β, and IL-6 levels significantly (p < 0.05), caffeine pretreatment reduced brain cytokine levels slightly but nonsignificantly (p > 0.05). Conclusion: Our results show that there is a clear relation between adenosinergic system and brain tissue cytokine levels. Our findings indicated that TNF-α, IL-1β, and IL-6 participate in the pathogenesis of generalized seizures, and the inhibition of TNF-α, IL-1β, and IL-6 with adenosinergic modulation may decrease seizure severity.

Since the discovery of nitric oxide (NO) as a neuronal messenger, its way to modulate learning and memory functions is subject of intense research. NO is an intercellular messenger in the central nervous system and is formed on demand through the conversion of L-arginine to L-citrulline via the enzyme nitric oxide synthase (NOS). Neuronal form of nitric oxide synthase may play an important role in a wide range of physiological and pathological conditions. Therefore the aim of this study was to investigate the effects of chronic 3-bromo 7-nitroindazole (3-Br 7-NI), specific neuronal nitric oxide synthase (nNOS) inhibitor, administration on spatial learning and memory performance in rats using the Morris water maze (MWM) paradigm. Male rats received either 3-Br 7-NI (20mg/kg/day) or saline via intraperitoneal injection for 5days. Daily administration of the specific neuronal nitric oxide synthase (nNOS) inhibitor, 3-Br 7-NI impaired the acquisition of the MWM task. 3-Br 7-NI also impaired the probe trial. The MWM training was associated with a significant increase in the brain-derived neurotrophic factor (BDNF) mRNA expression in the hippocampus. BDNF mRNA expression in the hippocampus did not change after 3-Br 7-NI treatment. L-arginine significantly reversed behavioural parameters, and the effect of 3-Br 7-NI was found to be NO-dependent. There were no differences in locomotor activity and blood pressure in 3-Br 7-NI treated rats. Our results may suggest that nNOS plays a key role in spatial memory formation in rats.

We aimed to evaluate the influence of current antifibrotic agents as well as the possible results obtained by combining these agents. This study included α-tocopherol, a strong antifibrotic and an efficient neuromediator of pathways used by other agents.Mitochondrial Bcl-2, Bax, cytochrome c and cytoplasmic caspase-3 expression, as well as toxic effect patterns, mitosis and cellular reactions due to α-tocopherol alone or combined with paclitaxel, mitomycin C and 5-flurouracil (5-FU), was studied in series obtained from human endothelial and primary Tenon's fibroblast cell cultures.The strongest apoptotic effect in both cell groups belonged to paclitaxel, followed by mitomycin C, and despite the overall suppressive effect of the α-tocopherol combination, mitomycin C increased its efficiency on the endothelial cells. The apoptosis/necrosis ratio was highest in α-tocopherol and lowest in paclitaxel, with α-tocopherol generally decreasing necrosis. Bax was observed at a high level with mitomycin C. Cytotoxicity was the highest with paclitaxel, and the caspase-3 reaction was markedly higher with mitomycin C in both cell types. In the α-tocopherol and 5-FU slides, mitosis and a layered formation were observed. The addition of α-tocopherol reduced the cytotoxicity of all antifibrotic agents in both cell series by decreasing the cell numbers, leading to necrosis.Alone or in combination, the use of α-tocopherol and 5-FU is safer than other agents. By suppressing the cytotoxic effects of other antifibrotic agents, α-tocopherol is a promising drug for improving the effects of antifibrotics in many aspects of medicine. In addition, it has the potential to play a role beyond its antioxidant and antifibrotic activity in ocular surgery.

We investigated the effects of inorganic mercury exposure during gestational/lactational periods on the behaviour, learning and hearing functions in a total of 32, 5-week-old and 5-month-old WAG/Rij rats (equally divided into 4 groups as 5-week and 5-month control mercury exposure groups). We evaluated the rats in terms of locomotor activity (LA), the Morris-water-maze (MWM) test and the passive avoidance (PA) test to quantify learning and memory performance; we used distortion product otoacoustic emission (DPOAE) tests to evaluate hearing ability. There were no significant differences between the 5-week-old rat groups in LA, and we detected a significant difference (p < 0.05) in the HgCl2-treated group in PA, MWM and DPOAE tests compared with the control group. The HgCl2-treated 5-week-old group exhibited worse emotional memory performance in PA, worse spatial learning and memory performances in MWM. There were no significant differences between the groups of 5-month-old rats in LA, MWM or PA. However, the DPOAE tests worsened in the mid- and high-frequency hearing thresholds. The HgCl2-treated 5-month-old group exhibited the most hearing loss of all groups. Our results convey that mercury exposure in young rats may worsen learning and memory performances as well as hearing at high-frequency levels. While there was no statistically significant difference in the behavior and learning tests in adult rats, the DPOAE test produced poorer results. Early detection of effects of mercury exposure provides medicals team with an opportunity to determinate treatment regimens and mitigate ototoxicity. DPOAE test can be used in clinical and experimental research investigating heavy metal ototoxicity., EXCLI Journal; 15:Doc391; ISSN 1611-2156

A branched methacrylated poly(caprolactone-co-lactic acid) and methacrylated poly(tetramethylene ether glycol) (PTMG-IEM) resins were synthesized. 1H-NMR spectroscopy, attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) spectroscopy, and gel permeation chromatography confirmed the chemical structures of copolymers. The photoinitiated polymerization of formulation composed of various amounts of methacrylated poly(caprolactone-co-lactic acid), PTMG-IEM, poly(ethylene glycol) diacrylate, water, and photoinitiator were performed. The curing reactions were followed by photo-DSC (Differential scanning calorimetry). Gel fraction was calculated from the insoluble part and found as ≥93%. Swelling and contact angles were measured, and all increased with the increasing amount of PTMG-IEM in network formulations. In vitro degradation studies were performed at 37 °C in phosphate-buffered saline (pH 7.4). Collagen-modified polymers were also prepared and introduced as a bioactive moiety to modify the polymer to enhance cell affinity. To compare the cell adhesion affinity to the polymer with and without collagen, cell growth experiments were performed. The results showed that collagen improves the cell adhesion onto the polymer surface. With the increasing amount of collagen, cell viability increases 86% (ECV304, p

The aim of this study was to develop biodegradable, photo-polymerizable in situ gel-forming systems prepared from a fumaric acid monoethyl ester (FAME) modified poly(lactide-co-glycolide) (PLGA) copolymer. By reacting lactide and glycolide in the presence of stannous octoate as a catalyst and 2-ethyl, 2-hydroxymethyl 1,3-propanediol as an initiator, hydroxyl terminated branched PLGA was synthesized. Afterwards, at room temperature hydroxyl terminated branched PLGA was reacted with fumaric acid monoethyl ester (FAME). N,N'-dicyclohexylcarbodiimide and triethylamine were used as a coupling agent and catalyst, respectively. The gel percentage, equilibrium mass swelling, degradation profile and polymerization kinetics of the hydrogels were investigated. All of the results were influenced by the amount of FAME modified PLGA co-polymer. Biocompatibility of the hydrogels was examined by using MTT cytotoxicity assay. According to the results, hydrogels are biocompatible and cell viability percentage depends on the amount of PLGA co-polymer. While the amount was 15% in hydrogel composition, cell viability was 100%, but after increasing the PLGA co-polymer amount to 30% the viability reduced to 78%. (C) Koninklijke Brill NV, Leiden, 2011

Abstract 4326 Intensive treatment of acute lymphoblastic leukemia in children has brought an increase of total remissions but also an increase of various complications resulting from toxicity of the treatment itself. One of the side effects of the use of cytostatics is their suppressive effect on the immune system. As an important element of the immune system, NK (Natural Killer) cells have critical roles in many different functions such as infection control, cancer surveillance, fetal implantation and cytokine production that will be affected by the immune suppresion. Dysfunctions of the NK cells by treatment are both of quantitative and qualitative nature. Our aim with this study is to analyze qualitative and quantitative chemotherapy induced changes on NK cells in children with acute lymphoblastic leukemia. Thirty three children aged between 2 and 19 years were included in the patient group. Their immunphenotypes, risk groups, prophylactic cranial radiation status and clinical characteristics were recorded. According to ALL BFM 2000 protocol, patients were classified into three groups: group 1 (patients who finished protocol M), group 2 (patients still on maintenance chemotherapy) and group 3 (patients who finished treatment). Control group (group 4) consisted of eleven healthy children aged between 2 and 13 years. NK cytotoxicity test, flow cytometric analysis of NK subgroups, cytokine analysis were performed in blood samples taken with informed consent from parents of both patients and controls. Clinical characteristics of the patients were evaluated with these results. Analysis was performed with “one way ANOVA” statistical test using SPSS 14.0. In 1:1 E:T ratio, group 2's NK cytotoxicity was significantly higher than any other group (p NK cells and subgroups in quantity seem to have decreased by the maintenance chemotherapy but not their functions. Group 2's (patients on maintenance therapy) higher NK cytotoxicity value may be due to low dose radiation's augmentation effect on NK cell functions as group 2 mostly consists of patients treated with prophylactic cranial radiation. A better understanding of NK cells changed by chemotherapy and radiotherapy will give us the opportunity of developing treatment that enhance their functions and so will contribute to the life quality of children with acute lymphoblastic leukemia (This project is sponsored by Istanbul University Research Fund, project number: T-889/02062006). Disclosures: Aksu Uzunhan: Istanbul University Istanbul Medical Faculty: Employment; Istanbul University Research Fund: Research Funding.

Abstract 4770 Hematopoietic stem cells which can self-renew, are very important for regeneration of hematopoietic system. Because, in chemotherapy applications, malign cells are killed but on the other hand normal cells are also damaged. It is known that corticosteroids, which is essential drug for all chemotherapy protocols, efficiently induce apoptosis not only in malign cells also in normal hematopoietic cells. But, there are no comprehensive studies about the apoptotic effects of glucocorticoids on pure CD34+ hematopoietic cell population. In several studies, it has been showed that hematopoietic cytokines can prevent apoptosis caused by chemotherapy and decrease toxic effects of this drugs. In this study, for the first time, we investigated apoptotic effects of corticosteroids on CD34+ hematopoietic stem cell population collected from human peripheral blood buffy coats by using immunomagnetic positive selection method and protective effects of hematopoietic cytokines. Buffy coats were obtained from standard blood collection bags of voluntary blood donors. Two control groups are composed that is not including cytokines in serum free medium (SFC) and induced with cytokine coctail that including interleukin 3, thrombopoietin, stem cell factor and flt3/flk2 ligand (CC). Test groups are dexamethasone group (D), prednisolone group (P) and groups induced with cytokines before drug application (CD, CP). High concentrations of dexamethasone (10-3 M) and prednisolone (10-3 M) were used in vitro in concordance with clinical treatment doses. To determine apoptotic mechanisms, immunohistochemical staining was carried out by using monoclonal antibodies against fas, caspase 3, sitocrom c, bax and bcl2. Then cells were counting and determining degree of peroxidase reactions were quantified using H-score. For statistical analysis paired t-test and one sample t-test were used. As a result, both dexamethasone and prednisolon induce apoptosis in pure CD34+ cells. When compared with control groups, corticosteroids caused significant increase for apoptotic fas, caspase 3, sitocrom c and bax (p Disclosures: Cetin: Istanbul University Research Fund: Employment, Research Funding. Kuruca:Istanbul University Research Fund: Research Funding.

1H-Indole-2,3-dione (isatin) is an endogenous compound identified in many organisms, possesses a wide range of biological activities. Biological properties of isatin include a range of actions in brain and offer protection against certain types of infections. This molecule has a versatile moiety that displays diverse biological activities, including anticancer activity. The discovery of numerous biologically active 3-substituted 2-indolinones led in the past decade to extensive synthesis of related compounds and as a result, anticancer agents were developed. In particular, among the 5-substituted analogs tested in the growth inhibitions against several human cancer cell lines, 5-halide, methoxy and trifluoromethoxy groups containing 3-substituted 2-indolinones show high antiproliferative effects. For this purpose, we first synthesized twelve 5-fluoro-1H-indole-2,3-dione-3-thiosemicarbazones that antituberculosis activities were shown previously by our teamwork and we researched anticancer drug potential in this study. The cytotoxic effects of twelve thiosemicarbazone derivatives were investigated by MTT assay in chronic myeloid leukemia cell lines (K562, HL60), B-lymphoma cell lines (P3HR1) and in vincristine resistant forms. The IC50 values (IC50 is a concentration that kills 50% of cells) were calculated from dose-response curve according to cytotoxicity index. The effectiveness of thiosemicarbazone derivatives were evaluated by comparing IC50 values in leukemic cell lines. All of the compounds were found cytotoxic in B-lymphoma cell lines (P3HR1, P3HR1Vin) in range 0.95–2.41 μM. However, the allyl derivative of thiosemicarbazones has cytotoxic activity in all the cancer cell lines (K562, K562Vin, HL-60, P3HR1, P3HR1Vin) that were tested. As a result, 5-fluoro-1H-indole-2,3-dione-3-thiosemicarbazones derivates might have chemotherapeutic drug potential in B-lymphoma patients. The allyl derivative of thiosemicarbazones has benefit both B-lymphoma and chronic myeloid leukemia patients in a large spectrum.