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WOS: 000361222600010, Poly (maleic anhydride-co-vinyl acetate) (MAVA) copolymer was synthesized by free-radical-polymerization reaction in methyl ethyl ketone (MEK) at 80 degrees C using benzoyl-peroxide (BPO) as the radical-initiator. MAVA was then modified with anti-leukemic chemotherapy-agent cytosine beta-D-arabinofuranoside hydrochloride (CF). Modification was performed at 70 degrees C in dimethylformamide (DMF) containing triethylamine (Et3N) as the catalyst. Structural characterization of the copolymer and copolymer/drug couple (MAVA/CF) was carried out by Fourier Transform Infrared (FTIR) and Nuclear Magnetic Resonance (H-1-NMR). FTIR and H-1-NMR spectra confirmed the modification reaction. UV-Spectrophotometric measurements indicated that MAVA/CF kept its molecular integrity in physiological-body-fluid, PBS, for first four days. Antiproliferative activities of MAVA/CF were also determined by BrdU-cell-proliferation-ELISA assays using C6 and HeLa cell lines (cisplatin and 5-fluorouracil used as positive control). MAVA/CF appeared to have little antiproliferative activity against C6 cell line while samples didn't have antiproliferative activity against HeLa cell line at low concentrations (, Sciences Research Projects Foundation of Cumhuriyet University [F258, F339], This work was supported by the Sciences Research Projects Foundation of Cumhuriyet University (Project No: F258 and F339).

WOS: 000315167100021, Poly[(maleic anhydride)-co-(vinyl acetate)] (MAVA) copolymer was synthesized by free radical polymerization reaction, in methyl ethyl ketone at 80 degrees C, using benzoyl peroxide as the initiator. The copolymer was then modified with a biomolecule, noradrenaline (NA). The modification reaction was performed at 70 degrees C in dimethylformamide containing triethylamine as the catalyst. The modified polymer was named MAVA/NA. Structural characterization of the copolymer and the modified product was carried out by Fourier transform infrared (FTIR) and 1H NMR and 13C NMR spectroscopy. The FTIR, 1H NMR and 13C NMR spectra confirmed that NA was successfully covalently bound to the MAVA copolymer backbone. Surface morphology was visualized by atomic force microscopy. The cumulative release of NA from MAVA/NA was determined in phosphate buffered saline solution for 7 days at 37 degrees C and compared with MAVA. Cytotoxicity of the MAVA/NA was evaluated by using a mouse fibroblast cell line (L929). Results obtained indicated that MAVA/NA had almost no toxicity and no negative effect on cell viability at 250 mu g mL1 concentration. (c) 2012 Society of Chemical Industry, Science Research Projects Foundation of Cumhuriyet University [F258], This work was supported by the Science Research Projects Foundation of Cumhuriyet University (Project F258).

WOS: 000361222900006, Poly(maleic anhydride-co-styrene) (MAST), poly(maleic anhydride-co-vinyl acetate) (MAVA), poly(maleic anhydride-co-methyl methacrylate) (MAMMA), poly(maleic anhydride-co-allyl phenyl ether) (MAAFE) and poly(maleic anhydride-alt-acrylic acid) (MAAA) copolymers were synthesized by free radical chain polymerization reaction. Modification/derivatization of the copolymers with active pharmaceutical ingredients, in amine form (-NH2), was performed by the ring opening reaction. Structural characterization of the copolymers and the conjugated products was carried out by Fourier Transform Infrared (FTIR) and Nuclear Magnetic Resonance (H-1-NMR). The FTIR and H-1-NMR spectra, confirmed that pharmaceutically active agents were covalently bonded to the MAVA copolymer in a succesfull manner. Furthermore cytotoxicity on healthy fibroblast cell lines, antiproliferative activity on cancer cell lines and antibacterial activity on bacterial strains were also investigated in-vitro for synthesized conjugates. MAVA copolymer was also selected the most suitable carrier for modification/derivaritization process by comparing its affinity to the pharmaceutically active agents.

WOS: 000343720300010, Water-soluble maleic anhydride-containing poly[maleic anhydride-alt-acrylic acid] (poly(MA-alt-AA) or MAAA) copolymer was synthesized by freer-adical chain polymerization reaction, in 1,4-dioxane in the presence of benzoyl peroxide, 0.1 %, as the radical initiator at 70 degrees C under a nitrogen atmosphere. The purified copolymer was then modified with an anti-external fungal and anti-cancer active agent, acriflavine (AF). The modification reaction was performed 48 h at 70 degrees C in dimethylformamide organic media, using triethylamine (TEA or Et3N) as the catalyst. The modified or conjugated copolymer/drug couple was named as MAAA/AF. Detailed structural characterization of the copolymer (MAAA) and modified product (MAAA/AF) was carried out by Fourier Transform Infrared (FTIR) and Nuclear Magnetic Resonance (H-1-NMR and C-13-NMR). The obtained FTIR, H-1-NMR, and C-13-NMR spectra confirmed that AF was successfully bound to the MAAA copolymer backbone by ring-opening reaction. Antimicrobial susceptibility of the MAAA, AF, and MAAA/AF was evaluated by Kirby Bauer Disc Diffusion method on Mueller-Hinton Agar using Enterecoccus faecium, Enterohaemorrhagic Escherichia coli (EHEC), Staphylococcus aureus and Listeria monocytogenes. Results obtained indicated that MAAA/AF had antibacterial activity on EHEC and S. aureus at 50, 40, and 30 mu g. A mechanism for MAAA and AF was then also suggested for the conjugation reaction., Sciences Research Projects Foundation of Cumhuriyet University [F258], This work was supported by Sciences Research Projects Foundation of Cumhuriyet University (Project No: F258). Structural characterizations were carried out at Hacettepe University, Ankara, Turkey.

WOS: 000317637800008, PubMed ID: 22475454, Background and purpose: For conformal radiotherapy, it is feasible to achieve high accuracy in contouring the outline of the target volume in treatment planning process. In contouring process, target volume is occasionally defined by means of either surgical clips or skin marker during patient anatomical data acquisition. Treatment planning systems are predicting invalid radiation dose distributions by using surgical clips and skin marker within the patient. Purpose of this study is the production of new skin marker which affects less dose distributions of electron beam. Materials and methods: The influences of lead and commercial markers on dose calculations in a 3D treatment planning systems were investigated in terms of electron beam energy and dose profile depth. Dose deviation with commercial marker was observed to smaller than lead marker. However this dose deviation was still at big value. In order to reduce of this value, barium sulfate suspension and ultrasound gel were mixed with different volumetric ratio. With the purpose of acception the most suitable marker for radiation therapy, obtained new suspensions were investigated in terms of visibility and dose deviation. Results: B:G/1:10 marker was determined to cause optimum visibility and the lowest dose deviation on dose calculations in terms of electron beam energy and dose profile depth. Conclusions: Appropriate marker, mixture of substances such as barium sulfate suspension and ultrasound gel can be produced. This marker is both ease of usage and practical and economical. Each clinic can prepare marker which is peculiar to suspension with different concentration of substance for specific visibility. But, it should be taken into account resultant dose deviation to beam calculation depending on barium sulfate concentration. (C) 2012 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

WOS: 000319496400007, PubMed ID: 23713427, Poly(maleic anhydride-co-styrene) (MAST) was synthesized by a free-radical polymerization reaction. A bioactive molecule, procainamide hydrochloride (PH), was then conjugated to MAST. The conjugation product was named as MAST/PH. Structural characterization of MAST and MAST/PH was carried out by Fourier Transform Infrared and Nuclear Magnetic Resonance spectroscopy. Their molecular weights were determined by size-exclusion chromatography. A mechanism was then suggested for the conjugation reaction. The results of the cytotoxicity assay, employing a mouse fibroblast cell line (L929), indicated that MAST/PH had no cytotoxicity at concentrations 62gmL(1) (p>0.05). Antiproliferative activities of MAST/PH and PH were determined by the BrdU cell proliferation ELISA assay, using C6 and HeLa cell lines. In the experiment, two anticancer chemotherapy drugs, cisplatin and 5-fluorouracil, were included as positive control. Antiproliferative activity results demonstrated that MAST/PH yielded the highest suppression profile (approximately 42%) at 20g/ml, while free PH exerted the same activity at 100g/ml. Interestingly, both MAST/PH and PH suppressed the proliferation of only one of the cell lines, C6 cells. Both cisplatin and 5-fluorouracil yielded approximately 60% antiproliferative activity on C6 cells at 20 and 100g/ml concentrations. Antiangiogenic capacity of both MAST and MAST/PH was also investigated by using the chicken chorioallantoic membrane assay. Results obtained indicated that while MAST/PH could be included into the category of good antiangiogenic substances, the activity score of MAST was within the weak category., Sciences Research Projects Foundation of Cumhuriyet University [F258], This work was supported by Sciences Research Projects Foundation of Cumhuriyet University (Project No: F258). The structural characterizations were carried out at Technology Research and Developing Centre, Erciyes University, Kayseri, Turkey.

WOS: 000314064600009, PubMed ID: 23052789, Acanthamoeba keratitis (AK) is a potentially devastating and sight-threatening infection of the cornea caused by the ubiquitous free-living amoebae, Acanthamoeba species. Its eradication is difficult because the amoebas encyst, making it highly resistant to anti-amoebic drugs. Acriflavine neutral (ACF) has been used for treatment of microbial infections for humans and fishes. The aim of our study was to evaluate the time-dependent cytotoxicities of ACF against Acanthamoeba spp. Trophozoites and cysts of three different strains (strain PAT06 Acanthamoeba castellanii, strain 2HH Acanthamoeba hatchetti, and strain 11DS A. hatchetti) of Acanthamoeba spp. were tested. All strains had been isolated from patients suffering from a severe AK. The effects of the ACF with the concentrations ranging from 15 to 500 mg mL(-1) on the cytotoxicity of Acanthamoeba strains were examined. ACF showed a time- and dose-dependent amebicidal action on the trophozoites and cysts. Pat06 (A. castellanii) was the most resistant, while strain 11DS (A. hatchetti) was the most sensitive. As a result, ACF could be concluded as a new agent for the treatment of Acanthamoeba infections. On the other hand, it still needs to be further evaluated by in vivo test systems to confirm the efficiency of its biological effect.

WOS: 000312708100007, PubMed ID: 22937886, Aim. The aim of this study was to investigate the effect of radiation doses very close to the human dose for oral cancers on mechanical, chemical and physical properties for poly methyl-methacrylate (PMMA). Methods. PMMA samples were divided into four different groups: no irradiated group, 25-Gy irradiated group, 50-Gy irradiated group and 75-Gy irradiated group. Each group contained nine samples. After 24 h, a three-point loading test was applied to each PMMA groups. The transverse strength and the elastic modulus were calculated using the test results. The results were analyzed statistically by using one-way analysis of variance. The structural characterizations of the PMMA samples were carried out by a Fourier Transform Infrared (FTIR) spectrophotometer to evaluate the chemical structure differences. Results. The transverse strength values of 25-Gy, 50-Gy and 75-Gy radiation groups were significantly higher than that of the no radiation group (p < 0.05). There was no significant difference among the elastic modulus values of the study groups (p > 0.05). The FTIR findings demonstrated that the irradiation process did not change the chemical structure of the PMMA polymeric materials. Conclusion. The therapeutic radiation doses increase the mechanical properties of the PMMA; however, the chemical and structural properties have no effect. When the findings of this study are taken into account, it can be said that patients can wear dentures during the radiotherapy.

WOS: 000294772400076, Maleic anhydride copolymer was modified with another biologically active agent, noradrenaline (NA), using both chemical and enzymatic methods. The modification and synthesized products were named as follows: chemical modification, MASTNAc; enzymatic modification, MASTNAe; enzymatically synthesized MASTNA from individual monomers, MASTNAem. Chemical and enzymatic reactions were performed at 70 degrees C and 38 degrees C, respectively. In the chemical reactions azobisisobutyronitrile was used as the initiator. In the enzymatic reactions, an extracellular extract, including an enzyme with peroxidase-like activity, was used. All the reactions were performed in an organic medium, methyl ethyl ketone. Structural characterization of the copolymer and modified copolymer were carried out by Fourier transform infrared (FTIR) and nuclear magnetic resonance ((1)H NMR). FTIR and (1)H NMR spectra confirmed that NA was successfully covalently bound onto the MAST copolymer backbone by both chemical and enzymatic methods. Surface morphology of the samples was studied by scanning electron microscopy. Results obtained indicated that chemical and enzymatic addition of NA to MAST backbone yielded products having quite similar physical and chemical properties. On the other hand, MASTNA-modified copolymer synthesized by individual monomers appeared to be different in its chemical structure. Furthermore, enzymatic modification and synthesis appeared to provide a good alternative method because it required much milder conditions such as low temperature, and better product qualities: higher solubility in water, higher yield and purity. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 122: 2821-2828, 2011

WOS: 000318710600009, Three maleic anhydride copolymers were synthesized by free-radical copolymerization. The synthesized products were named as follows: maleic anhydride-styrene (MAST); maleic anhydride-vinyl acetate (MAVA), and maleic anhydride-methyl methacrylate (MAMMA). Initiators used in the reactions were azobisisobutyronitrile (AIBN, 70 A degrees C, benzene) for MAST and benzoyl-peroxide [BPO, 80 A degrees C, methyl ethyl ketone (MEK)] for MAVA and MAMMA. Structural characterizations were carried out by Fourier transform infrared (FTIR) and nuclear magnetic resonance [H-1 NMR, C-13 NMR, and C-13-APT (attached-proton test)] spectrometry. Surface morphology was studied by scanning electron microscopy (SEM). Solubility of the copolymers was examined in water and in twelve different organic solvents. Cytotoxicity of the copolymers and the solvents was evaluated by using a mouse fibroblast cell line (L929), copolymers had almost no toxicity. Of the twelve organic solvents, acetone, MEK, and tetrahydrofuran (THF) produced the least toxicity. MEK was found to be the best solvent and used for the solvation of the copolymers., Sciences Research Projets Foundation of Cumhuriyet University [F258], This study was supported by Sciences Research Projets Foundation of Cumhuriyet University (Project No.: F258).

WOS: 000400971300013, Drug carrier, poly(maleic anhydride-co-vinyl acetate) (MAVA or poly[MA-co-VA]) copolymer, was traditionally synthesized by free radical chain polymerization reaction, in methyl ethyl ketone (MEK) organic media at 80 A degrees C, using benzoyl peroxide (BPO) as the radicalic initiator. The purified copolymer was then modified with a chemotherapeutic agent, doxorubicin hydrochloride (DOX) at 75 A degrees C for 72 h, using N-(3-dimethyl-aminopropyl)-N'-ethylcarbodiimide hydrochloride (EDAC) as the carboxylic acid-activating agent. Structural characterization of the MAVA and the modified MAVA/DOX conjugate was carried out by Fourier transform infrared (FTIR) and nuclear magnetic resonance (H-1-NMR and C-13-NMR). Their molecular weights were determined by size-exclusion chromatography (SEC). The spectroscopic and SEC results confirmed that conjugated/modification reaction was successfully carried out. UV spectrophotometric measurements indicated that MAVA/DOX preserved its molecular stability in physiological body fluid, PBS (physiological pH 7.40 at 37 A degrees C). Antiproliferative activities of MAVA/DOX were determined by BrdU cell proliferation ELISA assay using C6 (Rat Brain tumor cells) and HeLa (human uterus carcinoma) cell lines in vitro by comparing with free DOX agent (reference compound). Although MAVA showed low antiproliferative activity, both MAVA/DOX and DOX exhibited greater activity against HeLa and C6. Lactate dehydrogenase (LDH) leakage assay was performed for MAVA/DOX and DOX, which detected a non-toxic effect against C6 even at the highest dose (100 mu g/mL). IC50 and IC75 values were also determined using ED50 plus v1.0. Molecular modeling at M06-L/6-31 + G(d,p)//AM1 level showed that the electron density in MAVA/DOX is more localized resulting a higher polarization and thereby a higher dipole moment which shed light on the solubility of MAVA/DOX conjugate., Sciences Research Projects Foundation of Cumhuriyet University [F258, F339], This work was supported by Sciences Research Projects Foundation of Cumhuriyet University (Project No: F258 and F339). Structural characterizations were carried out at Technology Research and Developing Centre, Erciyes University, Kayseri, Turkey. Average molecular weight distribution of MAVA and MAVA/DOX was analyzed by Size-Exclusion Chromatography (SEC) Measurements at Yildiz Technical University.

WOS: 000232291100013, Background: The biliary secretion of antibiotics decreases proportionately to an increase in intrabiliary pressure. The aim of this study was to evaluate the effect of bile duct obstruction on biliary secretion of meropenem. Material and Methods: 110 Wistar albino rats were used in this study. There were 11 groups each including 10 rats. In groups A1, B1, C1, D1, E1 and F, the common bile ducts were ligated for 7 days. In the control groups (A2, B2, C2, D2 and E2), sham surgery was performed. A single dose of 14 mg/kg of meropenem was infused intravenously for 10 min. The serum concentration of meropenem was measured 30 min later in groups A1 and A2, 1 h later in groups B1 and B2, 2 h later in groups C1 and C2, 4 h later in groups D1 and D2 and 6 h later in groups E1 and E2. In group F, the intrabiliary pressure was measured in situ on day 7 for confirmation. Results: The biliary / serum level ratio of meropenem in the obstructed rats within 30 min, 1, 2, 4 and 6 h of infusion was 163, 113, 67, 36 and 28%, respectively. The biliary/serum level ratio of meropenem in the control rats within 30 min, 1, 2, 4 and 6 h of infusion were 302, 149, 123, 127 and 126%, respectively. Conclusion: Compared to the control rats, the biliary levels of meropenem was reduced in the obstructed rats compared to control rats. However, the measured levels were greater than the minimum inhibitory concentration (MIC). After conduction of clinical studies, meropenem may be an ideal agent in the treatment of acute cholecystitis and cholangitis caused by obstruction of the biliary tract.