16 research outputs found

    How to change a shrimp into an intelligent drug carrier?

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    Design of hybrid systems (structures composed of a carrier and pharmacological agent) for controlled release inside the body is a major direction in creation of new forms of drugs. These novel drug carriers should possess better accessibility and effectiveness with limited side-effects. The main purpose of this study was to construct a new form of chitosan carrier with the ability to transform from sol to gel at the physiological temperature of human body. Controlled drug release systems were formed by mixing b-sodium glycerophosphate with the solutions of chitosan glutaminate

    The malleable brain: plasticity of neural circuits and behavior: A review from students to students

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    One of the most intriguing features of the brain is its ability to be malleable, allowing it to adapt continually to changes in the environment. Specific neuronal activity patterns drive long-lasting increases or decreases in the strength of synaptic connections, referred to as long-term potentiation (LTP) and long-term depression (LTD) respectively. Such phenomena have been described in a variety of model organisms, which are used to study molecular, structural, and functional aspects of synaptic plasticity. This review originated from the first International Society for Neurochemistry (ISN) and Journal of Neurochemistry (JNC) Flagship School held in Alpbach, Austria (Sep 2016), and will use its curriculum and discussions as a framework to review some of the current knowledge in the field of synaptic plasticity. First, we describe the role of plasticity during development and the persistent changes of neural circuitry occurring when sensory input is altered during critical developmental stages. We then outline the signaling cascades resulting in the synthesis of new plasticity-related proteins, which ultimately enable sustained changes in synaptic strength. Going beyond the traditional understanding of synaptic plasticity conceptualized by LTP and LTD, we discuss system-wide modifications and recently unveiled homeostatic mechanisms, such as synaptic scaling. Finally, we describe the neural circuits and synaptic plasticity mechanisms driving associative memory and motor learning. Evidence summarized in this review provides a current view of synaptic plasticity in its various forms, offers new insights into the underlying mechanisms and behavioral relevance, and provides directions for future research in the field of synaptic plasticity.Fil: Schaefer, Natascha. University of Wuerzburg; AlemaniaFil: Rotermund, Carola. University of Tuebingen; AlemaniaFil: Blumrich, Eva Maria. Universitat Bremen; AlemaniaFil: Lourenco, Mychael V.. Universidade Federal do Rio de Janeiro; BrasilFil: Joshi, Pooja. Robert Debre Hospital; FranciaFil: Hegemann, Regina U.. University of Otago; Nueva ZelandaFil: Jamwal, Sumit. ISF College of Pharmacy; IndiaFil: Ali, Nilufar. Augusta University; Estados UnidosFil: García Romero, Ezra Michelet. Universidad Veracruzana; MéxicoFil: Sharma, Sorabh. Birla Institute of Technology and Science; IndiaFil: Ghosh, Shampa. Indian Council of Medical Research; IndiaFil: Sinha, Jitendra K.. Indian Council of Medical Research; IndiaFil: Loke, Hannah. Hudson Institute of Medical Research; AustraliaFil: Jain, Vishal. Defence Institute of Physiology and Allied Sciences; IndiaFil: Lepeta, Katarzyna. Polish Academy of Sciences; ArgentinaFil: Salamian, Ahmad. Polish Academy of Sciences; ArgentinaFil: Sharma, Mahima. Polish Academy of Sciences; ArgentinaFil: Golpich, Mojtaba. University Kebangsaan Malaysia Medical Centre; MalasiaFil: Nawrotek, Katarzyna. University Of Lodz; ArgentinaFil: Paid, Ramesh K.. Indian Institute of Chemical Biology; IndiaFil: Shahidzadeh, Sheila M.. Syracuse University; Estados UnidosFil: Piermartiri, Tetsade. Universidade Federal de Santa Catarina; BrasilFil: Amini, Elham. University Kebangsaan Malaysia Medical Centre; MalasiaFil: Pastor, Verónica. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Biología Celular y Neurociencia ; ArgentinaFil: Wilson, Yvette. University of Melbourne; AustraliaFil: Adeniyi, Philip A.. Afe Babalola University; NigeriaFil: Datusalia, Ashok K.. National Brain Research Centre; IndiaFil: Vafadari, Benham. Polish Academy of Sciences; ArgentinaFil: Saini, Vedangana. University of Nebraska; Estados UnidosFil: Suárez Pozos, Edna. Instituto Politécnico Nacional; MéxicoFil: Kushwah, Neetu. Defence Institute of Physiology and Allied Sciences; IndiaFil: Fontanet, Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Biología Celular y Neurociencia ; ArgentinaFil: Turner, Anthony J.. University of Leeds; Reino Unid

    Understanding Electrodeposition of Chitosan–Hydroxyapatite Structures for Regeneration of Tubular-Shaped Tissues and Organs

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    Tubular-shaped hydrogel structures were obtained in the process of cathodic electrodeposition from a chitosan–hydroxyapatite solution carried out in a cylindrical geometry. The impact of the initial concentration of solution components (i.e., chitosan, hydroxyapatite, and lactic acid) and process parameters (i.e., time and voltage) on the mass and structural properties of deposit was examined. Commercially available chitosan differs in average molecular weight and deacetylation degree; therefore, these parameters were also studied. The application of Fourier-transform infrared spectroscopy, scanning electron microscopy, and time-of-flight secondary ion mass spectrometry allowed obtaining fundamental information about the type of bonds and interactions created in electrodeposited structures. Biocompatible tubular implants are highly desired in the field of regeneration or replacement of tubular-shaped tissues and organs; therefore, the possibility of obtaining deposits with the desired structural properties is highly anticipated

    Fabrication and Characterization of Polycaprolactone/Chitosan—Hydroxyapatite Hybrid Implants for Peripheral Nerve Regeneration

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    Major efforts for the advancement of tubular-shaped implant fabrication focused recently on the development of 3D printing methods that can enable the fabrication of complete devices in a single printing process. However, the main limitation of these solutions is the use of non-biocompatible polymers. Therefore, a new technology for obtaining hybrid implants that employ polymer extrusion and electrophoretic deposition is applied. The fabricated structures are made of two layers: polycaprolactone skeleton and chitosan–hydroxyapatite electrodeposit. Both of them can be functionalized by incorporation of mechanical or biological cues that favor ingrowth, guidance, and correct targeting of axons. The electrodeposition process is conducted at different voltages in order to determine the influence of this process on the structural, chemical, and mechanical properties of implants. In addition, changes in mechanical properties of implants during their incubation in phosphate-buffered solution (pH 7.4) at 37 °C up to 28 days are examined. The presented technology, being low-cost and relatively simple, shall find a broad scope of applications in customized nerve tissue engineering

    Fabrication and Characterization of Polycaprolactone/Chitosan—Hydroxyapatite Hybrid Implants for Peripheral Nerve Regeneration

    No full text
    Major efforts for the advancement of tubular-shaped implant fabrication focused recently on the development of 3D printing methods that can enable the fabrication of complete devices in a single printing process. However, the main limitation of these solutions is the use of non-biocompatible polymers. Therefore, a new technology for obtaining hybrid implants that employ polymer extrusion and electrophoretic deposition is applied. The fabricated structures are made of two layers: polycaprolactone skeleton and chitosan–hydroxyapatite electrodeposit. Both of them can be functionalized by incorporation of mechanical or biological cues that favor ingrowth, guidance, and correct targeting of axons. The electrodeposition process is conducted at different voltages in order to determine the influence of this process on the structural, chemical, and mechanical properties of implants. In addition, changes in mechanical properties of implants during their incubation in phosphate-buffered solution (pH 7.4) at 37 °C up to 28 days are examined. The presented technology, being low-cost and relatively simple, shall find a broad scope of applications in customized nerve tissue engineering

    Investigation of Parameters Influencing Tubular-Shaped Chitosan-Hydroxyapatite Layer Electrodeposition

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    Tubular-shaped layer electrodeposition from chitosan-hydroxyapatite colloidal solutions has found application in the field of regeneration or replacement of cylindrical tissues and organs, especially peripheral nerve tissue regeneration. Nevertheless, the quantitative and qualitative characterisation of this phenomenon has not been described. In this work, the colloidal systems are subjected to the action of an electric current initiated at different voltages. Parameters of the electrodeposition process (i.e., total charge exchanged, gas volume, and deposit thickness) are monitored over time. Deposit structures are investigated by scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR). The value of voltage influences structural characteristics but not thickness of deposit for the process lasting at least 20 min. The calculated number of exchanged electrons for studied conditions suggests that the mechanism of deposit formation is governed not only by water electrolysis but also interactions between formed hydroxide ions and calcium ions coordinated by chitosan chains

    Structural characteristics of thermosensitive chitosan glutaminate hydrogels

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    Hydrogels that possess the ability of gelling in response to changes in the local environment, such as pH or temperature, have been examined extensively recently. In this paper the properties of thermosensitive chitosan hydrogels prepared with the use of chitosan glutaminate and -glycerophosphate are presented. The sol/gel transition point was determined based on the rheological properties. The structure of gels was observed under the Scanning Electron Microscopy (SEM) and was investigated by thermogravimetric (TG) and differential themogravimetric (DTG) analy¬sis and infrared (IR) spectroscopy. The crystallinity of gel structure was determined by X-ray Diffraction analysis (XRD)

    Structural characteristics of thermosensitive chitosan glutaminate hydrogels

    No full text
    Hydrogels that possess the ability of gelling in response to changes in the local environment, such as pH or temperature, have been examined extensively recently. In this paper the properties of thermosensitive chitosan hydrogels prepared with the use of chitosan glutaminate and -glycerophosphate are presented. The sol/gel transition point was determined based on the rheological properties. The structure of gels was observed under the Scanning Electron Microscopy (SEM) and was investigated by thermogravimetric (TG) and differential themogravimetric (DTG) analy¬sis and infrared (IR) spectroscopy. The crystallinity of gel structure was determined by X-ray Diffraction analysis (XRD)

    Cytotoxicity of chitosan based thermo-sensitive hydrogels intended for nervous tissue engineering

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    The damage to the central nervous system is one of the most difficult cases of trauma to treat. Over the last few years, increasing attention has been focused on the development of strategies based on biomaterials for regeneration and repair of the spinal cord injury. In particular, materials in the form of hydrogels based on chitosan are being actively investigated due to their intrinsic properties that are favorable in spinal cord tissue regeneration. The purpose of this study was to develop a thermo-gelling chitosan solution that will be prepared with the use of acids that naturally occur in the human nervous tissue. For this purpose, two types of chitosan gels were prepared based on chitosan glutamate and chitosan lactate. In order to reduce toxic action of the system obtained gels were conditioned in distilled water with pH 5.00. The changes in the structures of systems obtained were determined with the use of FTIR method. Biocompatibility was primarily evaluated through cytotoxicity testing by MTT assay with respect to mouse fibroblast cells
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