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Öğe Chitosan film containing fucoidan as a wound dressing for dermal burn healing: Preparation and in Vitro/In vivo evaluation(SPRINGER, 2007) Sezer, Ali Demir; Hatipoğlu, Fatih; Cevher, Erdal; Oğurtan, Zeki; Baş, Ahmet Levent; Akbuğa, JulideThe aim of this study was to develop chitosan film containing fucoidan and to investigate its suitability for the treatment of dermal burns on rabbits. Porous films, thickness between 29.7 and 269.0 mu m, were obtained by the solvent dropping method. Water vapor permeability (3.3-16.6/0.1 g), the swelling (0.67-1.77 g/g), tensile strength (7.1-45.8 N), and bioadhesion (0.076-1.771 mJ/cm(2)) of the films were determined. The thinnest films were obtained with the lowest chitosan concentration (P < .05). The water absorption capacity of the films sharply increased with the freeze-drying technique. The film having the thickness of 29.7 mu m showed the highest amount of moisture permeability (16.6 g/0.1 g). Higher chitosan concentration significantly increased tensile strength of the films (P < .05). Using higher concentration of lactic acid made films more elastic and applicable, and these films were selected for in vivo studies. Seven adult male New Zealand white rabbits were used for the evaluation of the films on superficial dermal burns. Biopsy samples were taken at 7, 14, and 21 days after wounding, and each wound site was examined macroscopically and histopathologically. After 7 days treatment, fibroplasia and scar were observed on wounds treated with fucoidan-chitosan film. The best regenerated dermal papillary formation, best reepithelization, and the fastest closure of wounds were found in the fucoidan-chitosan film treatment group after 14 days compared with other treatment and control groups. It can be concluded that fucoidan-chitosan films might be a potential treatment system for dermal burns and that changing formulation variables can modulate the characterizations of the films.Öğe Cytologic-enzymologic diagnosis of experimental pneumonia induced by klebsiella pneumoniae serotype II in rats and its treatment with free and liposomal enrofloxacin(KAFKAS UNIV, VETERINER FAKULTESI DERGISI, 2013) Baş, Ahmet Levent; Üney, Kamil; Hadimli, Hasan Hüseyin; Sezer, Ali Demir; Hatipoğlu, Fatih; Maden, Mehmet; Akbuğa, JulideEnrofloxacin (ENR) rapidly localizes in eukaryotic cells in vitro but does not remain for prolonged periods, thereby reducing the ENR efficacy of defense against intracellular pathogens. Delivery of ENR in a liposome-encapsulated form may enhance its intracellular residence time. In this study, experimental pneumonia was induced in healthy and dexamethasone-treated rats using Klebsiella pneumoniae serotype II. Free and liposome-encapsulated ENR were injected intravenously into the infected animals at a dose of 7.5 mg/kg/day for 5 days. Samples of tissue, plasma and bronchoalveolar lavage (BAL) fluid were obtained at 1, 2, 3 and 4 days and 1, 2, 3 and 4 weeks after the first antibiotic treatment. All of the samples were evaluated cytologically, enzymologically, microbiologically and pathologically. It was determined that cytologic and enzymologic diagnoses of BAL fluid are not meaningful for evaluating the treatment of the experimental pneumonia in rats. However, it was established that the use of ENR in liposomal form at a dose of 7.5 mg/kg for 5 days is more effective than the free form both in the treatment of K. pneumoniae infections and in the prevention of recurrent infections. Liposome-encapsulated antimicrobial agents should provide another choice for antimicrobial therapy in the future, but further investigation must be completed before clinical use.Öğe Encapsulation of enrofloxacin in liposomes I: Preparation and in vitro characterization of LUV(INFORMA HEALTHCARE, 2004) Sezer, Ali Demir; Baş, Ahmet Levent; Akbuğa, JulideLiposomes are effectively used in the treatment of microbial infections. Higher cellular uptake has been reported when antibiotics are encapsulated in liposomes. In this study, enrofloxacin (ENF) was encapsulated in large unilamellar vesicles (LUVs) and the effects of formulation variables on the liposome characteristics were investigated. Liposomes were prepared using dry lipid film method. A number of variables such as molar ratios of phospholipid (DPPC; DL-alpha-phosphatidylcholine dipalmitoyl), cholesterol, ENF and amount of alpha-tocopherol and the volumes of internal (chloroform) and external phases [phosphate buffered saline PBS (pH 7.4)] were studied. In vitro characterization of the liposomes including the encapsulation capacity, size and drug release properties were carried out. Using of this method, spherical LUV liposomes with high drug content could be produced. Particle size of liposomes changed between 3.12 and 4.95 mum. The molar ratios of DPPC, cholesterol and ENF affected the size of the liposome (p < 0.05). The drug encapsulation capacities were high and changed between 37.1% and 79.5%. The highest ENF encapsulation was obtained with the highest cholesterol content. An increase in the drug encapsulation capacity of the liposome was found with increasing molar ratios of DPPC, cholesterol and ENF (p < 0.05). Furthermore, the release of ENF from the liposomes decreased as the molar ratios of DPPC, cholesterol and ENF increased (p < 0.05). In conclusion, a convenient colloidal carrier for the controlled release of ENF can be prepared by changing the formulation parameters of LUVs.Öğe Evaluation of fucoidan-chitosan hydrogels on superficial dermal burn healing in rabbit: An in vivo study(ELSEVIER SCIENCE BV, 2005) Sezer, Ali Demir; Hatipoğlu, Fatih; Oğurtan, Zeki; Baş, Ahmet Levent; Akbuğa, Julide[Abstract not Available]Öğe In vitro evaluation of enrofloxacin-loaded MLV Liposomes(INFORMA HEALTHCARE, 2007) Sezer, Ali Demir; Akbuğa, Julide; Baş, Ahmet LeventFluoroquinolones are broad-spectrum antimicrobial agents that seem to reach their intracellular target site ( DNA gyrase) in Escherichia coli by means of an uptake process through the outer and inner membranes. Delivery of quinolones with liposomes has many advantages than the free form of the drug. Liposomes may represent an excellent device for improving the selective transport of antibiotics in these respects. In this study, enrofloxacin-loaded multilamellar vesicles (MLVs) were prepared and the effects of formulation variables on the liposome characteristics were investigated. Liposomes were prepared by using the dry lipid film method. A number of variables, such as phospholipid (DL-alpha-phosphatidylcholine dipalmitoyl), cholesterol, enrofloxacin (ENF), stearylamine, and dicetyl phosphate molar ratios and alpha-tocopherol amounts, were studied. The liposome size, encapsulation capacity, drug release, stability, and electrophoretic mobility of ENF-loaded liposomes were determined. Using this method, spherical MLVs with high drug content could be produced. Particle size of liposomes changed between 1.63 and 3.31 mu m and liposome size was affected by all formulation variables ( p < 0.05) except molar ratio of ENF. MLVs can be used as a carrier system for the controlled release of ENF. The highest encapsulation of ENF amount can be obtained using positively charged SA in the formulation and changing the formulation parameters can vary drug release patterns.Öğe New nanosphere system for treatment of full-thickness burn on rabbit(BLACKWELL PUBLISHING, 2006) Sezer, Ali Demir; Hatipoğlu, Fatih; Oğurtan, Zeki; Baş, Ahmet Levent; Cevher, Erdal; Akbuğa, Julide[Abstract not Available]Öğe Preparation of Fucoidan-Chitosan Hydrogel and Its Application as Burn Healing Accelerator on Rabbits(PHARMACEUTICAL SOC JAPAN, 2008) Sezer, Ali Demir; Cevher, Erdal; Hatipoğlu, Fatih; Oğurtan, Zeki; Baş, Ahmet Levent; Akbuğa, JulideTreatment of dermal wounds with macromolecular agents such as natural polymers is one of the research areas of the biomaterial science. Fucoidan is a sulphated polysaccharide which is commonly obtained from seaweeds. The great number of studies on the different pharmacological properties of fucoidan is present, but there is limited information about using of fucoidan in the treatment of dermal burns. The aim of this study was to prepare fucoidan-chitosan hydrogels and to investigate their treatment efficiency on dermal burns. Hydrogels were prepared by swelling the polymers in acidic solution and their swelling, mechanical (hardness, cohesiveness and adhesiveness) and bioadhesive properties were investigated. The viscosity and water absorption capacity of formulations increased with increase in the polymer concentration. In contrast to the cohesiveness results, the adhesiveness of hydrogels increased with the polymer concentration. The bioadhesion was changed between 0.012-0.142 mJ.cm(-2) and enhanced with addition of fucoidan into gel formulations. It was formed dermal burns on seven adult male New Zealand white rabbits and the optimum gel formulation applied on the wounds. Control and treatment group biopsy samples were taken on days 7, 14 and 21 and each burn wound site was evaluated histopathollogically. No edema was seen in tested groups except control after 3 d treatment. After 7 of treatment, fibroplasia and scar were fixed on wounds treated with fucoidan-chitosan gel and fucoidan solution. The best regeneration on dermal papillary formation and the fastest closure of the wounds were observed in fucoidan-chitosan hydrogels after 14 d treatment.Öğe The use of fucosphere in the treatment of dermal burns in rabbits(ELSEVIER SCIENCE BV, 2008) Sezer, Ali Demir; Cevher, Erdal; Hatipoğlu, Fatih; Oğurtan, Zeki; Baş, Ahmet Levent; Akbuğa, JulideThe aim of this study was to prepare a new microsphere (fucosphere) system based on polyion complexation of fucoidan with chitosan, and to evaluate its treatment efficiency on dermal burns. The physicochemical properties such as mean particle. size and distribution, zeta potential and bioadhesive properties of the microspheres were investigated. The formulation which had the high surface charge, narrow size distribution and the highest bioadhesive property was selected and applied on seven male New Zealand white rabbits with dermal burns. Biopsy samples were taken on day 7, 14 and 21. Each burn site was evaluated macroscopically and histopathologically and the findings were compared with controls of fucoidan solution and chitosan microspheres. The microspheres between the size ranges of 367 and 1017 nm were obtained. The work of bioadhesion of microspheres, with the surface charges +6.1 to +26.3 mV, changed between 0.081 and 0.191 mJ cm(-2). Macroscopically and histopathological observations indicated that the fastest healing of the burns was obtained in group treated with fucosphere after 21 days of treatment (P < 0.05). Rete peg formation values and nuclear organize regions (NORs) were higher with treated facospheres than the other groups on day 14. In conclusion, in vitro and in vivo evaluation of fucospheres indicated that the new microsphere system shortened the treatment period of burns and provided fast and effective healing by improving regeneration and re-epithelization. Hence fucosphere may find application in the treatment of dermal burns. (C) 2007 Elsevier B.V. All rights reserved.