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Volume 0, Issue 0 (8-2024)
Abstract

Nowadays, the seismic performance-based design of structures has been widely noticed by the engineering community. So, different methods for performance-based design have been presented by different researchers. This attitude has been included in the design code and regulations for seismic design of new buildings and retrofit of existing buildings. The FEMA P-58 performance-based design method presented by the Pacific Earthquake Engineering Research (PEER) can quantify the consequences related to the seismic response of buildings. Therefore, using this method, the seismic performance of buildings can be directly evaluated. In addition, this performance-based design method can define simpler criteria such as repair cost, repair time, and casualties for seismic evaluation and decision-making process. The method is based on considering different sources of uncertainty in earthquake input and its intensity, structural response, associated damage, and repair cost, using the concepts of conditional probability and total probability theorem. In this method, the building is designed in such a way that it meets the expected and predetermined performance level in a specific level of seismic excitation. Since the performance levels of the building are determined based on the amount of damage caused to structural and non-structural members, one of the practical and effective ways to evaluate performance is to estimate the building repair cost. In the approach presented in FEMA P-58, the repair cost is defined in a probabilistic approach, as the cost needed to restore the damaged parts to their original state in the form of expected annual loss. In this research, first, three 4-, 12-, and 20-story office buildings with the lateral force resisting system of reinforced concrete special moment frames were selected in a high seismic risk area. Then, the nonlinear model of structures was provided in OpenSEES software. In order to reduce the computational cost and analysis time, the single-bay Substitute Frame model was used to simplify the multi-bay reinforced concrete moment frames. All four structures were subjected to Incremental Dynamic Analysis (IDA) for 30 earthquake records. A probabilistic relationship between the spectral acceleration of the earthquake and the main damage parameter (i.e. the inter-story drift), as well as the collapse fragility curve, was obtained. Then, the repair cost including the cost of repairing structural members as well as beams and columns, the cost of repairing non-structural members as well as partition and curtain walls, and the cost of replacing collapsed structures was calculated as expected annual loss. The results show that the repair costs at the Design-Based Earthquake (DBE) for 4-, 12-, and 20-story buildings are 3%, 2.5%, and 10% of the building replacement cost and at Maximum Credible Earthquake (MCE) are 22%, 23%, and 38% of the building replacement cost, respectively. In addition, in short buildings, most of the cost is caused by repairing structural and non-structural members, and in tall buildings, most of the cost is caused by replacing collapsed or severely damaged structures. Considering two nonstructural elements (i.e. partition and curtain walls) in repair cost, the analysis results show that the cost of repairing structural elements is more than the cost of repairing non-structural elements.

Volume 1, Issue 1 (12-2010)
Abstract

Multiple sclerosis (MS) is commonest demyelinating disease among young adults. It demonstrates neurological dysfunctions in females more than males. Gonadal hormones have essential roles in maturation and differentiation of neurons and glial cells in both genders. The role of some gonadal female hormones such as progesterone has been well characterized on demyelination and remyelination in animal models. The role of androgens on neural system development and myelin maturation were identified. We previously observed that castration decreases the brain resistance against demyelinating insults and also reduces the subsequent repair. As the optic nerves and chiasm demyelination shows the hallmark characteristic in MS, inducing demyelination in optic apparatus, we have tried to find whether the effects of elimination of male gonadal hormones using gonadectomy could show the same, more or less changes in patterns of demyelination and repair comparing demyelinated females? Thus, to evaluate these alternations castrated male and female rats were compared by using visual evoked potentials and histological assessments on 2,7,14, and 28 days post lysolecithine (LPC) injection. Interestingly, we observed demyelination was started 2 day post lesion (dpl), reached to a maximum level at 7 and 14 dpl and then it partially but significantly reversed on 28 dpl. Demyelination and subsequent repair processes in both gonadectomized and female groups were shown almost the same patterns temporarily and in quality. Elimination of gonadal androgens could cause the male animals to undergone the same shape of de/remyelination compared female ones. In conclusion, differences between male and female demyelination and remyelination are substantially depending on male gonadal androgens. This work could be useful for understanding of the effects of sex hormones on demyelinating diseases and could offer fundamental information for repairing therapies in Multiple Sclerosis.

Volume 1, Issue 1 (4-2014)
Abstract

Background: Differentiation ofmesenchymal stem cells (MSCs) to hepatocyte-like cells could be associated with development of liver function factors. The impact of differentiation-dependent changes on DNA integrity is not well understood. In this study, hepatocytes and their progenitor stem cells were treated with aflatoxin B1 (AFB1) and amplification of selected genes linked to DNA damage was examined. Methods: MSCs and CD34+ cells isolated from umbilical cord blood (UCB) were treated with AFB1 (0, 2.5, 10 and 20 µM) in selective media supporting the hepatocyte differentiation. After 24 htreatment the DNA damage (Comet assay) and amplification rates ofP53 and β-globin genes were measured using real time polymerase chain reaction (QPCR). Results:The results show that AFB1 treatments resulted in a concentration- dependent increase in the DNA damage and suppression of the specific gene amplification. The extent of DNA damage was significantly greater in hepatocytes differentiated from MSCs when compared to those obtained from CD34+ cells. The effects of AFB1 on the rate of selected gene amplification in QPCR showed that the lesions (expressed as lesions/10 kb) in P53 and β-globin genes was significantly greater in hepatocytes derived from MSCs as compared to the cells derived from CD34+ cells. Conclusions: These data together with the results of cytochrome P450 (CYP3A4) expression in the cells suggest that the non-differentiated stem cells are probably less vulnerable to genotoxic agents as compared to hepatocytes differentiated from them.

Volume 1, Issue 1 (3-2023)
Abstract

Low Intensity Magnetic Separators (LIMS) are widely used in research and industry. The design of this separator is based on drum rotation inside a tank media, so that a permanent magnets placing inside the drum as an angle form, produces a magnetic field. In this study, the behavior of magnetic and none-magnetic particles of a pulp, flowing through a magnetic field in the wet LIMS, was simulated and validated by experimental results. The magnetic field variables were calculated in an FEM based simulator (COMSOL Multiphysics); while particles’ tracking was done applying CFD numerical method, enhanced by discrete phase model (DPM). The difference between the results of the simulation and the magnetic separation experimental test (recovery of magnetic particles in the concentrate product) was 16.4%. In order to quantify the results of the simulation, magnetic separation simulation was performed by changing two variables affecting the magnetic separation process (variables of particle size of the input pulp feed particles and solid percentage of input pulp) and corresponding experiments. Comparison of laboratory and simulation results showed that the trend of simulation results is consistent with laboratory results of the weight recovery (in both variables under study), so that the maximum simulation error is related to the size of 125 microns (16.5 %) and the lowest simulation error was in 180 microns (11.4 %). Also, the lowest simulation error in the weight recovery prediction was related to the pulp feed solid percentage of 15% (equivalent to 14%) and the highest simulation error was in 30% pulp feed solid percentage (16.9 %). This proposes that FEM-DPM-CFD coupling model, can be applied for simulation, optimization, design and construct 

Volume 1, Issue 2 (7-2014)
Abstract

Background: In recent years we have successfully adopted an in vitro hepatogenic differentiation of mesenchymal stem cells (MSCs). In this protocol the biologically active hepatocyte-like cells were differentiated from the stem cells isolated from either bone marrow or umbilical cord blood (UCB) samples. The aim of the present study was to compare the efficiency of the hepatogenic differentiation of MSCs isolated from UCB and MSCs. Methods: Differentiation process of MSCs was carried out in a selective medium supporting hepatogenic differentiation for 3 weeks. Then using specific markers we have examined the hepatocyte formation following hepatogenic differentiation of the stem cells. Hepatogenic markers namely albumin, α-fetoprotein (AFP) and cytochrome P450 3A4 (CYP3A4) were monitored at different time intervals during differentiation. Results: Transdifferentiation of the UCB and bone marrow MSCs was also characterized by measuring albumin, AFP and CYP3A4 at mRNA levels using reverse transcription polymerase chain reaction (RT-PCR). AFP was expressed in the undifferentiated UCB-MSCs and increased on day 21 of differentiation. However, AFP was not detected in the undifferentiated bone marrow MSCs. But, AFP expression started during the first week of differentiation. Albumin expression was detected in hepatocytes from UCB as well as bone marrow. The expression of albumin and its secretion from hepatocyte prepared from bone marrow appeared earlier compared to the cells derived from UCB. Metabolic function of the hepatocytes evaluated by secretion of albumin in the culture media was also similar in the cells isolated from both the sources. Conclusions: The differentiation potential of MSCs derived from human UCB and bone marrow under in vitro condition is comparable. However, it appears that there is time-dependent difference in the onset of expression of liver specific markers particularly albumin synthesis in hepatocytes derived from different stem cells.

Volume 1, Issue 2 (9-2020)
Abstract

Nowadays, countries are required to develop the architectural plans by using vernacular and climatic architectures so that they can provide comfort to residents in addition to protect them from adverse climate factors such as wind, cold, and extreme heat. Vernacular architecture in both Nepal and Iran is seen as a precious model of climate adaptive design. The cold and mountainous climate of these two countries has created special conditions for residents. The purpose of current paper is to record the climatic design patterns of the two countries and to compare them in order to present new approaches derived from the vernacular architecture. From this point of view, this article provides a great help to researchers and designers in this field. Moreover, the present research is derived from library, documentary and statistical sources in an analytical and research method and finally, the conclusion is comparative to the promotional approach and to the practical goals. The results were obtained after collecting, recording, and adjusting the climate design patterns of the two countries. Finally, Nepal's vernacular architectural solutions, which were in line with vernacular and climatic architecture, were presented to guide the vernacular architecture of Iran for the benefit of residents. It is hoped that by using these solutions, we can take a step forward in protecting the environment and saving energy.

Volume 1, Issue 2 (7-2023)
Abstract

In this paper, results of the study on heavy metals solubility behavior of Ni-Cd filter cakes in Iranian Zinc Mine Development Company (IZMDC) plants are investigated. The effects of pH, temperature, liquid/solid ratio and contact time on the release of heavy metals (Zn, Cd, Ni and Pb) into water media was examined. Also, “Extraction procedure tests” approved by EPA were applied to the residues. Moreover, statistical data analysis was performed and the most important parameters for dissolution of Zn, Cd, Ni and Pb were found to be the pH and L/S.. The concentration of Cd and Pb in the extracts obtained from filter cakes by applying EPA extraction procedures at pH 5 are over 1.0 and 5.0 mg/L, which are toxicity limits, respectively. The concentrations of other metals in the solution are above the limits given by various quality standards for surface water.

 

Volume 1, Issue 3 (10-2014)
Abstract

Background: Age-related differences in the ethoxyresorufin O-deethylase (EROD) activity of CYP1A1 and its inducibility in rats may determine the toxic potential of acetaminophen.  This study was carried out to compare the effects of acetaminophen (APAP) and β-naphthoflavone (βNF) on CYP1A1 activity in young and adult rats. Methods: For this purpose, young and adult rats (n = four / group) were treated with different doses of APAP. Likewise groups of young and adult rats were treated with a single dose of β-naphthoflavone (βNF, 67 mg / kg b.w). EROD was measured in microsomal fraction using resorufin as the substrate. Results:The results showed that a single i. p. injection of APAP (25 mg / kg B.W.) failed to alter liver microsomal EROD in young and adults. Whereas, in adults treated with 250 and 450 mg APAP / kg B.W, liver CYP1A1 was elevated to about 45 and 60% respectively. The rate of CYP1A1 induction in young rats with single dose of APAP (450 mg/kg B.W) was approximately 32%. Induction in CYP1A1 was noticed 4 h after APAP injection and returned to normal levels in 24 h. The inducibility of CYP1A1 in rats treated with a toxic dose of APAP was comparable to the data obtained from animals treated βNF, 67 mg / kg b.w. Conclusion: These results together with our previous reports indicate a similar pattern of changes in CYP1A1 in both the age-groups treated with toxic doses of APAP may suggest that the inducible CYP1A1 can equally contribute to protection against liver damage in young and adult rats.

Volume 1, Issue 4 (12-2013)
Abstract

This paper presents the analysis of the onset and withdrawal dates and the duration of summer monsoon over Nepal for last 63 years (1951-2013). The trend analysis revealed that both the onset and withdrawal of summer monsoon are delayed in recent years. The statistical analysis using cumulative deviation and Worsley likelihood tests showed a step jump in mean withdrawal date after the year 1997. The mean withdrawal date after 1997 is later than the normal withdrawal date by 10 days. Although, the trend for onset is statistically insignificant, the trend for withdrawal is significant at 5% level. Stationarity tests for the period of 1951-1996 and 1997-2013 also revealed that both the onset and withdrawal series are non-stationary. A step change in withdrawal date with delayed trend on both onset and withdrawal coupled with longer duration suggests a temporal shift in the monsoon pattern over Nepal after 1997. The temporal shift in the monsoon is consistent with published findings on the effect of global climate change on the dynamics of the South Asian summer monsoon precipitation. The shifting pattern of the summer monsoon exerts a strong stress on agriculture, water resources, ecosystems, human health and the overall economy of the country.

Volume 1, Issue 4 (12-2021)
Abstract

How to recognize the separate substances given by Avicenna and Thomas Aquinas? Including metaphysical issues is the issue of the separate substances and how to recognize the separate substances. The complexity of the discussion of recognizing separate substances is that philosophers offer different and sometimes conflicting opinions when considering and reflecting on them. Among the medieval thinkers are Avicenna and Thomas Aquinas, each of them, by mentioning several reasons, expresses two opposing views regarding the recognition of the separate substances; As in some cases, they consider it possible for the human soul to know separate substances, and in some cases, they do not consider the human soul to be able to know. However, the views of the two thinkers are hesitant and inconsistent, but by analyzing their views and following the presentation of a dual division for cognition, that is, cognition of truth and true cognition, the apparent conflict can be resolved and finally, declare that according to both thinkers, the human soul can know the truth of the separate substances, with the difference that according to Avicenna, knowing the truth depends on the impartiality of the external active intellect, while according to Aquinas, knowing the truth requires the help of the inner active intellect.  On the other hand, both thinkers agree that the human soul can’t know the true essence of the separate substances; rather, true knowledge belongs to the separate substances and God. Finally, true knowledge separate substances cannot be achieved by acquiring knowledge.

Eisa Ebrahimi Dorche, Javad Motamedi Tehrani, Seyed Amir Hossein Goli Goli, Paria Akbari, Ali Nezameslami,
Volume 2, Issue 3 (12-2013)
Abstract

The effect of Artemia urmiana nauplii enriched with flaxseed oil on growth performance, survival and fatty acid composition of severum, Cichlasoma severum, larvae (0.3 mg initial weight) was investigated through a completely randomized block design with two treatments, viz., (1) larvae fed with plain nauplii, (2) larvae fed with nauplii enriched with flaxseed oil, in three replications. Results of the first biometry (day18th), showed a significantly higher survival rate in treatment 1 (81.87±0.29%) than treatment 2 (68.83±1.62%) (P<0.05), but there were no significant differences in the specific growth rates, the average weight and length gains between treatments (P>0.05). At the end of the second period of the experiment (day36th), significant differences in growth performance and survival rate was recorded between treatment 1 (97.82 ± 1.09%) and treatment 2 (91.16± 1.34%) (P>0.05).  The larvae was also found to convert n-3fatty acids to EPA and DHA.

Volume 2, Issue 4 (10-2016)
Abstract

Background: Hepatitis B infection is a major public health problem worldwide. Given that immune response towards the vaccine is not perfect, we aimed to evaluate circumstances of immune response in vaccinated students.
Materials and Methods: In this study, 219 medical students of Ardabil University of Medical Sciences were recruited, who had been administered vaccine series for the first time, and booster doses after one and six months completely. The serum samples were extracted from whole blood of the participants. The concentration of Hepatitis B surface antigen (HBsAg) and anti-HBs antibody (HBsAb) was measured using a commercial ELISA kit.
Results: It was observed that 201 cases (91.8%) out of 219 cases had positive anti-HBs antibody response, and 18 subjects (8.2%) were nonresponsive cases. Level of HBsAb was significantly different between males and females as well as alcoholics and non-alcoholics. None of the cases was identified as positive for HBsAg.
Conclusion: Considering the results of the present and previous studies in other countries, it can be claimed that the mass vaccination has been effective, especially in medical students.

Volume 2, Issue 5 (3-2009)
Abstract

The narratological approach in studying the fictional narrations structure provides an organized ground and a systematic pattern for analyzing the main elements of the narrative text, i.e. story and text. In the present research, the Do Donya (Two Worlds) is analyzed in a narratological approach and the first hypothesis of the research about the possibility of applying the structural of narratology for the modern fictional narration of Do Donya is tested. The reason for choosing the Do Donya fiction in the matters of deep structure, time, place and focusing is the conflicts and discrepancies which exist between death and life. The results indicate that the narratological approach with its componenets (including story level elements, such as time elements consisting of order, continuation and frequency; place elements consisting of fiction place and text place; characterization covering direct and indirect characterizations (action, speech, visual figure, environment and names deductions); focalization (internal and external); aspects of focalization conceptive, psychological and ideological)); narrating (the narrative levels (metafictional and subfictional), the narrative layers (internal and external)); representation of speech and thought (narration, crucibles (scenario, merely briefed scenario, indirect repetition of content, free indirect speech)) can present a structural analysis of all aspects of the narration of Do Donya story.

Volume 2, Issue 8 (12-2009)
Abstract

Eyn-ol Ghozat Hamedani is one of the prominent scholars and theosophists in the field of literary theory with lots of in-depth studies in this area. In his four excellent works, he has introduced fresh and unique ideas regarding the criticism and interpretation of the literary texts, among which one can point out: the relationship between expression and meaning; words’ connective and separative forms with respect to the meaning and content; the relation between poem and prose, and the mentality and the viewpoint of the reader; the impromptu writing especially in three stags including childhood, the state of wisdom, and the state of being in love. This study intends to analyze Eyn-ol Ghozat Hamedani’s works based on the frameworks proposed by him.

Volume 3, Issue 1 (8-2011)
Abstract

Education and Training were of great importance in Iran since ancient times. It was further developed along with Islam uprising. Education centers were also flourished at the same time. The process of the religious sciences schools initiated in Saljuqid era formally when the Nezamies were established. They continued their survival more or less until Qajar era, So that we find most of mosque-schools in Tehran as the time capital of the country that is why we believe that the study of such buildings from the view points of the architecture and the related decorations is a must. The greatest and the most important mosque-schools of the Qajar era in Tehran is the old Sepahsalar. It has experienced the least changes in more recent times; so it is an original sample of the mosque-schools. In this paper we attempt to study and consider the architecture and decorations characteristics of this building. Therefore, we evaluate its history, general map, spatial and functional elements and decorative methods applied in this mosque-school through a descriptive-analytical approach.

Volume 3, Issue 2 (11-2012)
Abstract

The stability of enzymes with no reduction in their catalytic activity still remains a critical issue in industrial applications. Naturally occurring osmolytes are commonly used as protein stabilizer. Apart from increasing the stability and catalytic activity, these osmolytes do not change the structure of enzyme. There are a few general schemes about the stabilization mechanism of these osmolytes but the details of their mechanism have not been found so far. In this study, we investigated the simultaneous effects of sorbitol and trehalose on the activity and structural stability of Pseudomonas cepacia lipase (PCL) using UV–visible, fluorescence and circular dichroism (CD) spectroscopy. In order to trace the refractive index and dielectric constant alterations upon the addition of osmolytes, microenvironment of the enzyme (PCL) was studied by means of SPR technique.The results revealed that osmolytes increased catalytic activity and intrinsic fluorescence intensity of PCL. In the presence of both osmolytes the activity of enzyme is greater than when each of the osmolytes is used individally. Far-UV CD spectra indicated that the secondary structural content of protein has been some what increased upon interacting with these osmolytes.The results of SPR technique indicated none of the above osmolytes could change the dielectric constant of medium considerably. This study revealed the synergy of two osmolytes toward increasing the activity and stability of enzyme.

Volume 3, Issue 3 (12-2019)
Abstract

In this study, the three phase mixed matrix membranes comprising Pebax®1657, PEG-200 and MIL-53(AL) nanoparticles were evaluated for CO2 gas separation. The effect of various PEG-200 and MIL-53(AL) concentration within the pebax polymeric matrix on the structure, gas permeability, and selectivity of the membranes was investigated. To study the cross-sectional morphology, crystallinity and thermal properties of the synthesized membranes, scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were utilized, respectively. Fourier transform infrared (FT-IR), was also carried out to identify the formation of the chemical bonds in the membrane. SEM images demonstrated a uniform cross-section and admissible dispersion of nanoparticles. The results of the thermal analyses indicated an increase in crystallinity and Tg in presence of MIL-53 particles. Permeation of pure gases (i.e., CO2, CH4) through the prepared neat Pebax®1657, the blended Pebax/PEG-200 and the Pebax/PEG-200/MIL-53(AL) mixed matrix membrane was measured at the pressure of 2–10 bar and temperature of 30 °C. The results showed that at the pressure 10 bar, the CO2 gas permeation from 133.36 barrer in pure membrane increased to 311.7 barrer (134%) in a membrane containing 10%wt MIL-53.
 

Volume 3, Issue 4 (3-2020)
Abstract

Research subject: In recent years, there are so many attractions in the field of effective detection and discrimination of volatile organic compounds (VOCs). Detection of VOCs compounds, are very important in many applications and industries such as air pollution control, air quality control, food packaging, food quality control, disease diagnostic, agriculture etc. The sensitivity and selectivity of the prepared sensors to detect of VOCs needs to improve.   
 Research approach: A conductive polymer composite sensitive layer based on poly (lactic acid) as polymer matrix and multiwall carbon nanotubes as conductive filler was prepared to detect of volatile organic compounds (VOCs). For this purpose the porous sensitive layer was prepared by non-solvent induced phase separation (NIPS) method. In this structure, chloroform (low boiling point temperature) was used as the solvent and ethanol (high boiling point temperature) was used as a non-solvent. The sensitive layer was used to detect of toluene, methanol, and chloroform. The structure and morphology of synthesized layer was investigated by means of scanning electron microscopy (SEM) and BET test.
Main results: The investigation indicated that the phase separation method induced the open cell morphology into the conductive composite. The BET results showed that the specific surface area of composite increased to 22.3 m2/gr. The experimental results showed that the response properties of porous layers was improved dramatically in comparison with dense layers. It was related to the increase of specific surface area of polymer composite and therefore the increase of diffusion coefficient of analyte molecules into the polymer matrix. Finally the sensitivity and selectivity of porous sensitive layers was investigated based on Flory-Huggins interaction parameter.
 

Volume 3, Issue 4 (3-2020)
Abstract

Research subject: Selectivity and permeability are the major parameters of polymeric membranes in gas separation process. Hence, nowadays in order to improve aforementioned parameters, modification and enhancement issues for such membrane have been highly noticed.
Research approach: In this study, in order to improve the performance of polymeric membranes, the two-component blend membranes containing Pebax®1657 and PVA were synthesized for CO2 separation. The effect of different PVA concentrations within the Pebax matrix on structure, morphology and gas separation properties of resultant membranes was investigated. The chemical bonds, crystallinity and cross-sectional morphology studied through, Fourier transform infrared (FTIR), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM), and were utilized.
Main results: The results of the thermal analysis indicated an increase in crystallinity and also glass transition temperature in presence of 5 – 15 wt.% PVA, while the membrane crystallinity decreased by increasing the PVA content up to 20 wt.%. FESEM images demonstrated a uniform cross-section without any cracks and defects for neat Pebax membrane but by adding PVA to Pebax matrix, appeared cracks and cave structures on the cross- section of blend membranes. The CO2/CH4 separation performance of membranes was measured using a constant volume set up at 30°C and feed pressure of 2, 6 and 10 bar. The obtained results revealed that the CO2 permeability in blend membranes improved as the PVA content increased within the membrane. The best obtained CO2 permeability was 204.64 Barrer which gained by Pebax/PVA (20wt.%) at feed pressure of 10 bar. Moreover, the highest selectivity of CO2/N2 for blend membrane with 15 wt.% of PVA was about 100.21 at 10 bar and 30°C.
 

Volume 4, Issue 1 (10-2013)
Abstract

Most patients with liver diseases are in the waiting list of liver implantation for a long period of time because of the lack of enough donors. Liver differentiation potential of Mesenchymal Stem Cells (MSCs) is a new perspective in curing these patients. Tissue engineering improves hepatocyte differentiation by coating the culture surfaces with Glycosaminoglycans (GAGs) such as Heparan Sulfate (HS). Cell detachment and death during hepatogenic differentiation hamper the efficiency of cell therapy. This study aims to establish a matrix. mimicking the liver extracellular matrix, which supports the attachment and proliferation potential of MSCs, as well. Collagen was physically coated on polystyrene plates. Collagen-GAG matrix was constructed by covalently immoblizing the HS molecules on collagen by EDC. Cell attachment and proliferation were evaluated by direct cell-counting and MTT methods. GAG presence on collagen was verified by Safranin O staining. Comparisons showed that the highest attachment belonged to collagen, collagen-HS and polystyrene, respectively. Collagen matrix showed also the highest cell proliferation. Collagen-GAG provided more suitable matrix for cell proliferation compared to polystyrene. The results further showed that biomimicked collagen-GAG matrix supports superior attachment and viability for MSCs compared to polystyrene.



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