Showing 11 results for Stem
Ahmad Gharzi,
Volume 1, Issue 1 (12-2014)
Abstract
Formations of feather and hair follicles during embryonic stage are nearly similar. The aim of the present research is to study the similarities and differences between these two follicles in adult pigeons and rats. To fulfill this task, feather and hair follicles were dissected and processed for light and electron microscopy. The results demonstrated that these two follicles were similar in having dermal papilla and epidermal matrix. Moreover, the production of feather fibers and hair in them, respectively, is almost similar. However, unlike the hair follicle, the feather follicle has a distinct compartment, called the pulp at the top of the papilla. At the center of this pulp and dermal papilla a blood vessel exists, a character never observed in the hair follicle. Another difference between the two related to the thickness of the basement membrane exists at the interface between the papilla and epidermal matrix which in feather follicle is much thicker than its hair equivalent. In addition, at the base of feather follicle there is a distinct population of stem-like cells which could not be distinguished in the hair follicle. Based on the results obtained in this study, it seems that the feathers in birds and the hairs in mammals have been adapted for different biological tasks.
Ehsan Hosseini, Mostafa Asadi,
Volume 3, Issue 2 (9-2016)
Abstract
Silene ghahremaninejadii (Caryophyllaceae) is described as a new species to science in this article based on critical differences in certain characters of both vegetative and reproductive organs, compared with its closely related taxa, i.e. S. marschallii and S. ruprechtii. The new species has compact caudex, glabrous leaves and pedicles, cylindrical calyx without indumentums on its inner surface, deeply bifid petals without coronal scales and glabrousfilaments. In addition, a hypothesis about the speciation process of the species is proposed.
Narges Vasefi, Shahriyar Saeidi Mehrvarz, Alireza Naqinezhad, Mokarram Ravanbakhsh,
Volume 3, Issue 3 (12-2016)
Abstract
This paper concerns itself with the study of sand beaches of the Boujagh National Park with an area of 3477 ha. The purposes of this study include the determination of the plant species diversity and plant groups. In ad-dition, the determination of the impact of environmental and specific variables on the presence or absence of certain species and their communities is another aim that the study follows. In order to attain those purposes, 52 plots across 6 transects of the district were used. In each plot, the materials were identified and abundance-dominance of species by using Braun-Blanquet criteria were obtained and their life forms were determined according to Raunkiaer clas-sification. To determine the plant groups, a Two-way analysis of significant modified species (Modified TWINSP-AN) was utilized. Detrended Canonical Analysis (DCA) was used to determine factors affecting plant groups. The results showed that four plant groups exist in this district: Convolvulus persicus-Crepis foetida subsp. Foetida grou-p, Argusia sibirica group, Eryngium caucasicum-Juncus acutus group and Rubus sanctus group. The first and seco-nd groups consist of higher percentages of therophytes and spread in areas where the soil contains more sand. Plants in the third and fourth groups spread in areas with stabilized sand and high percentage of silt. DCA analysis results showed that soil factors (texture, OC, Na, K, N, Ca, Mg) have significant relation with plant groups were studied. Among the plant groups, the percentage of silt and sand, species richness and life forms of therophytes and geop-hytes show significant relations. Therefore it can be concluded that these factors affect on the separation and distri-bution of plant groups.
Farhad Valizadegan, Maryam Rahimi Tesyie,
Volume 5, Issue 1 (6-2018)
Abstract
The Basolateral Amygdala (BLA) has modulatory effects on working and reference memory. The aim of this study was the evaluation of effects of dopaminergic system in the BLA of rats on working and reference memory behaviors. The number of working and reference errors and time spent in the arms by rats were measured in the radial arm maze according to DSWS protocol. The animals were cannulated in the BLA bilaterally. The microinjection of low dose (0.005µg/rat) and high dose (0.5 µg/rat) of apomorphine have indicated a significant decrease in number of working memory error. But, there was not any change in the numberof reference memory error that showing the improvement of working memory. While the injection of moderate dose apomorphine (0.05 µg/rat) increased these parameters and also enhanced the spent time in working arm that presenting both memories damage. The chlorpromazine injection (2 µg/rat) decreased the number of working and reference memory errors representing the improvement of these memories. Microinjection of chlorpromazine (2 µg/rat) with different doses of apomorphine had no significant change on the both number of errors and the time spent in comparison with control groups. These findings show that BLA dopaminergic system modulates the working and reference memory through that both of (D1/D2) receptors. Also, the effect of this system in BLA is the resultant function of the both receptor families.
Mahboobe Mohebi Bijarpas, Teymuor Rostami Shahraji, Habiboala Samizadeh Lahiji,
Volume 5, Issue 2 (9-2018)
Abstract
To understand the Eco physiological adaptation mechanisms of Fagus orientalis Lipesk to altitude changes, the activities of Peroxidase (POD), Catalase (CAT), and Ascorbate peroxidase (APX) in leaves of Fagus orientalis in different altitudes (A1: 700 m, A2: 1200 m, A3: 1700 m above sea level) Was studied in the forests of Guilan. The sampling of leaves was collected from southern and northern parts of the crown of healthy and mature trees. The results of analysis variance showed that there was a significant difference between and within the population for the activity of catalase and peroxidase enzymes at the probability level of 0.05 and with increasing altitude, the activity of catalase and peroxidase were increased but the activity of Ascorbate peroxidase enzyme was initially increased and its level of activity decreased from the middle altitude with increasing altitude. Also, the results showed that the enzymatic activity of peroxidase and catalase in the northern leaves was more than the southern leaves that collected in crown of the trees.
Neda Tekiyeh Maroof, Nahid Aboutaleb, Maryam Naseroleslami,
Volume 7, Issue 3 (11-2020)
Abstract
Superparamagnetic iron oxide nanoparticles (SPIONs) have made extensive advances in nanotechnology. The unique properties of these particles have expanded their application in various fields, including medicine. One of these applications is non-invasive analysis for cell tracking. However, the possibility of toxicity in cells is reported by these nanoparticles. Due to the fact that cellular damage caused by iron oxide nanoparticles is concentration-dependent, the determination of the appropriate concentration of iron oxide nanoparticles is very important to prevent cell damage or cell death due to apoptosis. The aim of this study was to find a concentration of SPIONs which does not result in apoptosis. Therefore, the effects of different concentrations of iron oxide nanoparticles on cell survival were investigated, and the their effects on increased gene expression involved in apoptosis (p53) in human amniotic membrane derived mesenchymal stem cells (hAMSCs) were evaluated. First, stem cells were extracted from human amniotic membrane tissue and cultured. To demonstrate the multipotent characteristic of hAMSCs, these cells were differentiated into adipose, bone, and chondrocyte cell lines. Then, the viability of the cells treated with different concentrations of iron oxide nanoparticles (200, 150, 100, 50, 0 μg / ml) over a period of 24 and 48 hours was evaluated by MTT method. The effect of the concentrations of 0, 100,150 and 200 μg / ml of nanoparticles after 24 hours in hAMSCs was investigated for the expression of p53 gene by Real-Time PCR. hAMSCs were spindle-shaped in a two-dimensional culture. Flow cytometry examination of surface markers revealed that these cells were able to express CD 29, CD90 and CD105 but they were unable to express CD34 and CD45. The results of the multi-potency assay of hAMSCs showed that these cells were capable of being differentiated into adipocyte, bone and chondrocyte cell lines. Iron oxide nanoparticles had no significant effect on cell survival at the concentrations of 50 and 100 μg / ml in 24 hours. However, cell viability decreased significantly after the concentration of 150 μg / ml (42 ± 1.4%, p<0. 001. The results of Real-Time PCR analysis showed that the expression of p53 gene significantly increased at concentrations of 150 (2.4±0.1, P < 0. 001) and 200 μg / ml (4.1 ± 0.11, P < 0. 001). According to the results, the nanoparticles used in this study were appropriate at concentrations ≥ 100 μg / ml for cell tracking.
Saeide Hosseini, Hamid Ejtehadi, Farshid Memariani, Mohammad Bagher Erfanian Taleii Noghan,
Volume 7, Issue 3 (11-2020)
Abstract
The Hezar-Masjed Mountain range is one of the main highlands of the northeasten Iran. The vegetation of its upper elevations has been poorly studied. This study aimed to compare the plant biodiversity of different aspects of the Hezar-Masjed Summit. A total number of 139 random 1m2 plots were recorded from different aspects of the study area. In each plot, the abundance and canopy cover percent of vascular plant species were recorded. Hill’s numbers (i.e., N1, N2) along with the Camargo evenness index and total species richness with bootstrapping approach were calculated. Rarefaction method was used to compare species richness among the aspects. Also, Hill’s diversity profile for each aspect was drawn. For each aspect, rank-abundance method was used to evaluate the dominant species. Biodiversity calculations and statistical analyses were performed using R software. The east- and south- facingslopes were found to have the highest and lowest indices in richness, evenness, and diversity, respectively. Despite adequate water availability in north-facing slopes, they show lower diversity than that of the east-facing slope, probably due to the of dominance of a poisonous species (Seseli transcaucasicum). Our results shown that in the Hezar-Masjed Summit, aspects have different biodiversity which is a result of their various environmental conditions.
Tahereh Sadat Mirahmadi, Farhad Valizadegan, Maryam Rahimi,
Volume 9, Issue 1 (3-2022)
Abstract
Hippocampus is a key structure in anxiety processing and memory storage. The purpose of this study was to investigate the interaction between GABAergic systems in CA1 area of hippocampus with morphinergic system in modulating of these behaviors. In this study, male wistar rats were cannulated with stereotaxic surgery in CA1 site. After a recovery period, morphine (µ opioid receptor agonist) was injected intraperitoneal, muscimol and bicuculline (GABAA receptor agonist and antagonist) were injected into the CA1. Parameters such as percentage of Open arms time (%OAT) and entries (%OAE) were calculated by means of an EPM apparatus. One-way ANOVA analysis showed that intraperitoneal administration of morphine increased %OAT and %OAE, indicating the anxiolytic effect of morphine. Based on paired sample T-test, the rate of memory formation improved. Pre-test intra-CA1 infusion of muscimol and bicuculline induced anxiolytic-like and anxiogenic-like behaviors, respectively; meanwhile, both drugs improved memory. Systemic injections of an effective dose of morphine combined with triple doses of muscimol showed a synergistic effect on memory formation and anxiety reduction. Simultaneous injection of morphine and bicuculline altered the negative effects of the latter on anxiety and increased the memory formation. This finding showed that GABAergic and opioidergic systems have similar effects on memory and anxiety in CA1 area.
Laleh Mavaddatiyan, Mahmood Talkhabi,
Volume 11, Issue 3 (12-2024)
Abstract
Ferroptosis, as a type of newly recognized iron-dependent programmed cell death, is closely related to aging. The aim of this study is to investigate the role of ferroptosis in the aging of mesenchymal stem cells (MSCs). GSE97311 dataset (containing expression data of fetal and adult MSCs) was analyzed and differentially expressed genes (DEGs) were extracted. Then, among them, ferroptosis-related differentially expressed genes (FRDEGs) were determined. In the next step, biological functions, protein-protein interactions, hub genes, upstream regulators, and inflammatory factors related to FRDEGs were analyzed using different bioinformatics methods. According to the analysis, 34 genes were identified as FRDEGs. Analysis of biological functions showed that these genes are mostly involved in oxidoreductase activities, fatty acid synthesis and response to iron ion. Also, the analyzes related to the signaling pathways also showed that these genes are mostly involved in the pathways related to types of cancers as well as fatty acid biosynthesis. According to the analysis, miR-26b-5p was identified as the most important miRNA and LINC00205 and GAS5 as the most important lncRNAs. Hub genes including HMOX1, EZH2, NEDD4L, PTGS2, CDKN2A, ATF3, NOX4, TXNIP, SNCA and MAPK3 were identified as the main genes of ferroptosis related to aging of MSCs.
Dr Behnaz Bakhshandeh, Alireza Shafizadeh Esfandabadi, Negin Kiaei, Mohammad Hosien Karimi,
Volume 12, Issue 1 (3-2025)
Abstract
Stem cells have received serious attention from the medical industry based on their unique abilities and characteristics for precise and personalized medical approaches. To optimize and modify the behavioral characteristics of these cells for various clinical and research applications, it is usually necessary to create phenotypic changes resulting from permanent or transient genetic manipulations in these cells. Previously radiation and chemical reagents were used for random mutation induction in their genome but today, with the development of targeted modification tools like nucleases, it is possible to change only the desired gene and trait both inside the genome and episomally. Favorable gene transferring is accomplished with the help of different biological, chemical, or physical mediators and procedures. This literature review addressed the importance and necessity of stem cell manipulations, stem cell genetic modification procedures and advantages and disadvantages of each method, as well as available solutions to improve the efficiency and security of mentioned methods for clinical approaches.
Dr. Maneezheh Pakravan, Mrs. Azam Javanbakht,
Volume 12, Issue 1 (3-2025)
Abstract
: Alcea species are valuable medicinal plants used in traditional medicine for a long time. The similarity between species and the diversity of traits have led scientists to use various biosystematics methods to identify species. In this study, the anatomical characteristics of the stem in 18 species of Alcea from Iran were examined. Hand sections in similar positions of the stem were studied and double staining with methyl green and carmine stain, and microscopic images were obtained. The most important traits analyzed in this study were the number of layers of collenchyma cells in the cortex, the thickness and number of layers of sclerenchyma fibers of the phloem, the number of vascular bundles, the ray parenchyma, the thickness of phloem and xylem vessels, and the structure of the pith. Then, cluster analysis using the Ward method was performed with SPSS software based on eight quantitative traits. The results showed that some of the stem's anatomical features, which are observed in closely related species, can only be useful for species identification but are not particularly helpful in grouping the species