Search for: rats
0.006 seconds
Total 51 records

    In vitro biocompatibility evaluations of hyperbranched polyglycerol hybrid nanostructure as a candidate for nanomedicine applications

    , Article Journal of Materials Science: Materials in Medicine ; Vol. 25, issue. 2 , 2014 , pp. 499-506 ; ISSN: 09574530 Zarrabi, A ; Shokrgozar, M. A ; Vossoughi, M ; Farokhi, M ; Sharif University of Technology
    In the present study, a detailed biocompatibility testing of a novel class of hybrid nanostructure based on hyperbranched polyglycerol and β-cyclodextrin is conducted. This highly water soluble nanostructure with size of less than 10 nm, polydispersity of less than 1.3, chemical tenability and highly branched architecture with the control over branching structure could be potentially used as a carrier in drug delivery systems. To this end, extensive studies in vitro and in vivo conditions have to be demonstrated. The in vitro studies include in vitro cytotoxicity tests; MTT and Neutral Red assay as an indicator of mitochondrial and lysosomal function, and blood biocompatibility tests such as... 

    Stimulus-specific adaptation decreases the coupling of spikes to LFP phase

    , Article Frontiers in Neural Circuits ; Volume 13 , 2019 ; 16625110 (ISSN) Parto Dezfouli, M ; Zarei, M ; Jahed, M ; Daliri, M. R ; Sharif University of Technology
    Frontiers Media S.A  2019
    Stimulus repetition suppresses the neural activity in different sensory areas of the brain. This mechanism of so-called stimulus-specific adaptation (SSA) has been observed in both spiking activity and local field potential (LFP) responses. However, much remains to be known about the effect of SSA on the spike–LFP relation. In this study, we approached this issue by investigating the spike-phase coupling (SPC) in control and adapting paradigms. For the control paradigm, pure tones were presented in a random unbiased sequence. In the adapting paradigm, the same stimuli were presented in a random pattern but it was biased to an adapter stimulus. In fact, the adapter occupied 80% of the... 

    Application of Bhattacharyya distance as a dissimilarity index for automated prediction of epileptic seizures in rats

    , Article 2010 International Conference on Intelligent and Advanced Systems, ICIAS 2010, 15 June 2010 through 17 June 2010 ; 2010 ; 9781424466238 (ISBN) Niknazar, M ; Vosoughi Vahdat, B ; Shamsollahi, M. B ; Sayyah, M ; Sharif University of Technology
    Seizures are defined as manifest of excessive and hypersynchronous activity of neurons in the cerebral cortex and represent a frequent malfunction of the human central nervous system. Therefore, the search for precursors and predictors of a seizure is of utmost clinical relevance and may even guide us to a deep understanding of the seizure generating mechanisms. In this study we analyzed invasive electroencephalogram (EEG) recordings in rats with experimentally induced generalized epilepsy with a nonlinear method called, dissimilarity index. In order to predict epileptic seizures automatically, Bhattacharyya distance between trajectory matrix of reference window, during an interval quite... 

    Alterations of the electroencephalogram sub-bands amplitude during focal seizures in the pilocarpine model of epilepsy

    , Article Physiology and Pharmacology ; Volume 16, Issue 1 , 2012 , Pages 11-20 ; 17350581 (ISSN) Motaghi, S ; Niknazar, M ; Sayyah, M ; babapour, V ; Vahdat, B. V ; Shamsollahi, M. B ; Sharif University of Technology
    Introduction: Temporal lobe epilepsy (TLE) is the most common and drug resistant epilepsy in adults. Due to behavioral, morphologic and electrographic similarities, pilocarpine model of epilepsy best resembles TLE. This study was aimed at determination of the changes in electroencephalogram (EEG) sub-bands amplitude during focal seizures in the pilocarpine model of epilepsy. Analysis of these changes might help detection of a pre-seizure state before an oncoming seizure. Methods: Rats were treated by scopolamine (1mg/kg, s.c) to prevent cholinergic effects. After 30 min, pilocarpine (380 mg/kg, i.p) was administered to induce status epilepticus (SE) and 2 hours after SE, diazepam (20 mg/kg,... 

    A unified approach for detection of induced epileptic seizures in rats using ECoG signals

    , Article Epilepsy and Behavior ; Volume 27, Issue 2 , 2013 , Pages 355-364 ; 15255050 (ISSN) Niknazar, M ; Mousavi, S. R ; Motaghi, S ; Dehghani, A ; Vosoughi Vahdat, B ; Shamsollahi, M. B ; Sayyah, M ; Noorbakhsh, S. M ; Sharif University of Technology
    Objective: Epileptic seizure detection is a key step for epilepsy assessment. In this work, using the pentylenetetrazole (PTZ) model, seizures were induced in rats, and ECoG signals in interictal, preictal, ictal, and postictal periods were recorded. The recorded ECoG signals were then analyzed to detect epileptic seizures in the epileptic rats. Methods: Two different approaches were considered in this work: thresholding and classification. In the thresholding approach, a feature is calculated in consecutive windows, and the resulted index is tracked over time and compared with a threshold. The moment the index crosses the threshold is considered as the moment of seizure onset. In the... 

    Long-term investigation on the phase stability, magnetic behavior, toxicity, and MRI characteristics of superparamagnetic Fe/Fe-oxide core/shell nanoparticles

    , Article International Journal of Pharmaceutics ; Volume 439, Issue 1-2 , 2012 , Pages 28-40 ; 03785173 (ISSN) Masoudi, A ; Madaah Hosseini, H. R ; Seyed Reyhani, S. M ; Shokrgozar, M. A ; Oghabian, M. A ; Ahmadi, R ; Sharif University of Technology
    To efficiently enhance the contrast obtaining from magnetic resonance imaging (MRI), pharmaceutical grade colloidal dispersions of PEG coated iron-based nanoparticles were prepared and compared to conventional pure iron oxide contrast agent. In this study, we synthesized ∼14 nm iron nanoparticles via NaBH4 reduction of iron(III) chloride in an aqueous medium. The resulting nanoparticles were further oxidized by two different methods via (CH3)3NO oxygen transferring agent and exposure to oxygen flow. XRD and electron microscopy analyses confirmed the formation of a second layer on the surface of α-Fe core. As magnetic measurements and Mössbauer spectra of 4-months post prepared nanoparticles... 

    The effect of poly(ethylene glycol) coating on colloidal stability of superparamagnetic iron oxide nanoparticles as potential MRI contrast agent

    , Article International Journal of Pharmaceutics ; Volume 433, Issue 1-2 , 2012 , Pages 129-141 ; 03785173 (ISSN) Masoudi, A ; Madaah Hosseini, H. R ; Shokrgozar, M. A ; Ahmadi, R ; Oghabian, M. A ; Sharif University of Technology
    Superparamganetic iron oxide-based contrast agents in magnetic resonance imaging (MRI) have offered new possibility for early detection of lymph nodes and their metastases. According to important role of nanoparticle size in biodistribution, magnetite nanoparticles coated with different polyethylene glycol (PEG) concentrations up to 10/1 PEG/iron oxide weight ratio in an ex situ manner. To predict the PEG-coated nanoparticle behavior in biological media, such as blood stream or tissue, colloidal stability evaluation was performed to estimate the coating endurance in different conditions. Accordingly, optical absorbance measurements were conducted in solutions with different values of pH and... 

    Completely 3dimensional Simulation of Urine Concentrating Mechanism in Rat Outer Medulla

    , M.Sc. Thesis Sharif University of Technology Sohrabi, Salman (Author) ; Saidi, Mohammad Said (Supervisor) ; Firoozabadi, Bahar (Co-Advisor)
    The urine formation and excretion system has long been of interest for mathematicians and physiologists to elucidate the obscurities within the process happen in renal tissue. In this study, a novel and absolutely three-dimensional approach is utilized for modeling urine concentrating mechanism in rat renal outer medulla which is essentially focused on demonstrating the significance of tubule's architecture revealed in anatomic studies and physiological literature. Since nephrons and vasculatures work interdependently through a highly structured arrangement in outer medulla which is dominated by vascular bundles, a highly detailed functional unit is proposed and also it is strongly justified... 

    Stimulus Signal Improvement in Order to Alleviate the Symptoms of Parkinson's Disease in Rat

    , M.Sc. Thesis Sharif University of Technology Gholipour, Saman (Author) ; Vosughi Vahdat, Bijan (Supervisor)
    Parkinson's disease is a degenerative disorder of the central nervous system. The motor symptoms of Parkinson's disease result from the death of dopamine-generating cells in the substantia nigra. The cause of this cell death is unknown. Early in the course of the disease, the most obvious symptoms are movement-related. Some of the symptoms are: shaking, rigidity, slowness of movement and difficulty with walking and gait. Modern treatments are effective at managing the early motor symptoms of the disease, mainly through the use of levodopa and dopamine agonists. As the disease progresses these drugs eventually become ineffective and produce a complication called dyskinesia, marked by... 

    Simulation of Urine Concentrating Mechanism in Rat Kidney Inner Medulla

    , M.Sc. Thesis Sharif University of Technology Sanatkhani, Soroush (Author) ; Saeedi, Mohammad Saeed (Supervisor)
    Physicians use charts that are prepared by experiments on animals or humans to prescribe drug dosage for patients. This method requires much more time by the Ministry of Health to approve new drugs to be used in health-care centers. Furthermore،we have no sight on how a specific drug is going to be diffuse in our body. In order to predict the distribution of a drug or any minerals in the kidney we need to model it. The first step would be modeling the important species that influence the urine concentrating mechanism. Due to the complications in modeling that mechanism especially in the inner medulla zone، we hadn’t solid information regarding that area. It is about half a century that... 

    Accelerated full-thickness wound healing via sustained bFGF delivery based on a PVA/chitosan/gelatin hydrogel incorporating PCL microspheres

    , Article International Journal of Pharmaceutics ; Volume 537, Issue 1-2 , 2018 , Pages 278-289 ; 03785173 (ISSN) Shamloo, A ; Sarmadi, M ; Aghababaie, Z ; Vossoughi, M ; Sharif University of Technology
    Elsevier B.V  2018
    Herein, a hybrid hydrogel/microsphere system is introduced for accelerated wound healing by sustained release of basic fibroblast growth factor (bFGF). The hydrogel is composed of a mixture of PVA, gelatin and chitosan. The double-emulsion-solvent-evaporation method was utilized to obtain microspheres composed of PCL, as the organic phase, and PVA, as the aqueous phase. Subsequently, various in-vitro and in-vivo assays were performed to characterize the system. BSA was used to optimize the release mechanism, and encapsulation efficiency in microspheres, where a combination of 3% (w/v) PCL and 1% (w/v) PVA was found to be the optimum microsphere sample. Incorporation of microspheres within... 

    Rhythmic air-puff into nasal cavity modulates activity across multiple brain areas: A non-invasive brain stimulation method to reduce ventilator-induced memory impairment

    , Article Respiratory Physiology and Neurobiology ; Volume 287 , 2021 ; 15699048 (ISSN) Ghazvineh, S ; Salimi, M ; Nazari, M ; Garousi, M ; Tabasi, F ; Dehdar, K ; Salimi, A ; Jamaati, H ; Mirnajafi Zadeh, J ; Arabzadeh, E ; Raoufy, M. R ; Sharif University of Technology
    Elsevier B.V  2021
    Mechanical ventilation (MV) can result in long-term brain impairments that are resistant to treatment. The mechanisms underlying MV-induced brain function impairment remain unclear. Since nasal airflow modulates brain activity, here we evaluated whether reinstating airflow during MV could influence the memory performance of rats after recovery. Rats were allocated into two study groups: one group received rhythmic air-puff into the nasal cavity during MV and a control group that underwent ventilation without air-puff. During MV, air-puffs induced time-locked event potentials in OB, mPFC and vHPC and significantly increased the oscillatory activity at the air-puff frequency. Furthermore, in... 

    The olfactory bulb modulates entorhinal cortex oscillations during spatial working memory

    , Article Journal of Physiological Sciences ; Volume 71, Issue 1 , 2021 ; 18806546 (ISSN) Salimi, M ; Tabasi, F ; Nazari, M ; Ghazvineh, S ; Salimi, A ; Jamaati, H ; Raoufy, M. R ; Sharif University of Technology
    BioMed Central Ltd  2021
    Cognitive functions such as working memory require integrated activity among different brain regions. Notably, entorhinal cortex (EC) activity is associated with the successful working memory task. Olfactory bulb (OB) oscillations are known as rhythms that modulate rhythmic activity in widespread brain regions during cognitive tasks. Since the OB is structurally connected to the EC, we hypothesized that OB could modulate EC activity during working memory performance. Herein, we explored OB–EC functional connectivity during spatial working memory performance by simultaneous recording local field potentials when rats performed a Y-maze task. Our results showed that the coherence of delta,... 

    Comparing the effects of endurance and resistance trainings on gene expression involved in protein synthesis and degradation signaling pathways of Wistar rat soleus muscle

    , Article Tehran University Medical Journal ; Volume 77, Issue 11 , 2020 , Pages 668-677 Gholipour, M ; Seifabad, M ; Asad, M. R ; Sharif University of Technology
    Tehran University of Medical Sciences  2020
    Background: Skeletal muscle mass, which is regulated by a balance between muscle protein synthesis and degradation, is an important factor for movement to meet everyday needs, especially in pathological conditions and aging. The purpose of the present investigation was to compare the alterations of the gene expression involved in muscle protein synthesis and degradation signaling pathways induced by two exercise training protocols. Methods: Eight weeks old Wistar rats have been assigned to the present experimental study, which was conducted from August 2018 to October 2018 at the animal laboratory of Tehran University. They were randomly divided into two resistance and endurance training... 

    Fabrication and evaluation of chitosan/gelatin/PVA hydrogel incorporating honey for wound healing applications: An in vitro, in vivo study

    , Article International Journal of Pharmaceutics ; Volume 592 , 2021 ; 03785173 (ISSN) Shamloo, A ; Aghababaie, Z ; Afjoul, H ; Jami, M ; Bidgoli, M. R ; Vossoughi, M ; Ramazani, A ; Kamyabhesari, K ; Sharif University of Technology
    Elsevier B.V  2021
    In this study, physically cross-linked hydrogels were developed by freezing-thawing method while different concentrations of honey were included into the hydrogels for accelerated wound healing. The hydrogel was composed of chitosan, polyvinyl alcohol (PVA), and gelatin with the ratio of 2:1:1 (v/v), respectively. Further, the effect of honey concentrations on antibacterial properties, and cell behavior was investigated. In vivo studies, including wound healing mechanism using rat model and histological analysis of section tissue samples were performed. The results illustrated that the incorporation of honey in hydrogels increased the ultimate strain of hydrogels approximately two times,... 

    Temporary skin grafts based on hybrid graphene oxide-natural biopolymer nanofibers as effective wound healing substitutes: pre-clinical and pathological studies in animal models

    , Article Journal of Materials Science: Materials in Medicine ; Volume 28, Issue 5 , 2017 , 73 ; 09574530 (ISSN) Mahmoudi, N ; Eslahi, N ; Mehdipour, A ; Mohammadi, M ; Akbari, M ; Samadikuchaksaraei, A ; Simchi, A ; Sharif University of Technology
    Springer New York LLC  2017
    Abstract: In recent years, temporary skin grafts (TSG) based on natural biopolymers modified with carbon nanostructures have received considerable attention for wound healing. Developments are required to improve physico-mechanical properties of these materials to match to natural skins. Additionally, in-deep pre-clinical examinations are necessary to ensure biological performance and toxicity effect in vivo. In the present work, we show superior acute-wound healing effect of graphene oxide nanosheets embedded in ultrafine biopolymer fibers (60 nm) on adult male rats. Nano-fibrous chitosan-based skin grafts crosslinked by Genepin with physico-mechanical properties close to natural skins were... 

    A comparative study of wound dressings loaded with silver sulfadiazine and silver nanoparticles: In vitro and in vivo evaluation

    , Article International Journal of Pharmaceutics ; Volume 564 , 2019 , Pages 350-358 ; 03785173 (ISSN) Mohseni, M ; Shamloo, A ; Aghababaie, Z ; Afjoul, H ; Abdi, S ; Moravvej, H ; Vossoughi, M ; Sharif University of Technology
    Elsevier B.V  2019
    In the current study, two series of antimicrobial dressings conjugated with silver sulfadiazine (SSD) and silver nanoparticles (AgNPs) were developed and evaluated for chronic wound healing. Highly porous polycaprolactone (PCL)/polyvinyl alcohol (PVA) nanofibers were loaded with different concentrations of SSD or AgNPs and compared comprehensively in vitro and in vivo. SSD and AgNPs indicated a strong and equal antimicrobial activity against S. aureus. However, SSD had more toxicity against fibroblast cells over one week in vitro culture. An in vivo model of wound healing on male Wistar rats was developed with a full thickness wound. All the wound dressings indicated enough flexibility and... 

    Mathematical Modeling of 188Re-PSMA in Rats and its Human Absorbed dose Estimation

    , M.Sc. Thesis Sharif University of Technology Hadisi, Maliheh (Author) ; Vosoughi, Naser (Supervisor) ; Yousefnia, Hassan (Supervisor) ; Bahrami Samani, Ali (Co-Supervisor)
    Prostate cancer is the second most common cancer in men and the fourth leading cause of death in the world. In this study, the 188Re-HYNIC-PSMA radiolabeled compound was produced as a compound for use in the treatment of prostate cancer and its metastases under optimal labeling conditions and its radiochemical purity was obtained above 98% using RTLC and HPLC chromatographic methods. This compound is stable at room temperature and in human blood serum for at least 48 hours after preparation. The biological distribution of this compound was investigated in each rat tissue and the amount of injected activity per unit mass of each tissue (%ID/g) was determined. The bio-distribution of 188... 

    Application of a dissimilarity index of EEG and its sub-bands on prediction of induced epileptic seizures from rat's EEG signals

    , Article IRBM ; Volume 33, Issue 5-6 , December , 2012 , Pages 298-307 ; 19590318 (ISSN) Niknazar, M ; Mousavi, S. R ; Shamsollahi, M. B ; Vosoughi Vahdat, B ; Sayyah, M ; Motaghi, S ; Dehghani, A ; Noorbakhsh, S. M ; Sharif University of Technology
    Objective: Epileptic seizures are defined as manifest of excessive and hyper-synchronous activity of neurons in the cerebral cortex that cause frequent malfunction of the human central nervous system. Therefore, finding precursors and predictors of epileptic seizure is of utmost clinical relevance to reduce the epileptic seizure induced nervous system malfunction consequences. Researchers for this purpose may even guide us to a deep understanding of the seizure generating mechanisms. The goal of this paper is to predict epileptic seizures in epileptic rats. Methods: Seizures were induced in rats using pentylenetetrazole (PTZ) model. EEG signals in interictal, preictal, ictal and postictal... 

    Effect of mozart music on hippocampal content of BDNF in postnatal rats

    , Article Basic and Clinical Neuroscience ; Volume 2, Issue 3 , 2011 , Pages 21-26 ; 2008126X (ISSN) Marzban, M ; Shahbazi, A ; Tondar, M ; Soleimani, M ; Bakhshayesh, M ; Moshkforoush, A ; Sadati, M ; Zendehrood, S. A ; Joghataei, M. T ; Sharif University of Technology
    Introduction: It has shown that listening to Mozart music can potentiate spatial tasks in human; and reduce seizure attacks in epileptic patients. A few studies have reported the effects of prenatal plus postpartum exposure of mice to the Mozart music on brain-drived neurotrophic factor (BDNF) in the hippocampus. Here we investigated the effect of postpartum exposure to The Mozart music on BDNF concentration in the hippocampus of rat. Methods: Thirty male one day old newborn Wistar rats divided randomly in two equal experimental and control groups. Experimental group exposed to slow rhythm Mozart music (Mozart Sonata for two pianos KV 448, 6 hour per day; sound pressure levels, between 80...