Publications by authors named "Keivan Moradi"

18 Publications

  • Page 1 of 1

Spectrum of PAH gene mutations in 1547 phenylketonuria patients from Iran: a comprehensive systematic review.

Metab Brain Dis 2021 Feb 24. Epub 2021 Feb 24.

Department of Biochemistry, School of Medicine, Kermanshah University of Medical Sciences, Parastar Street, Kermanshah, Kermanshah Province, Iran.

As one of the highest prevalence rates in the world, the prevalence of Phenylketonuria (PKU) in Iran has been estimated at 16.5 per 100,000 neonates. The objective of this study was to evaluate the spectrum and frequency of mutations of the phenylalanine hydroxylase (PAH) gene in Iranian PKU patients. A systematic review was carried out on previous studies on PAH gene mutations in Iranian PKU patients. A complete search was carried out on the on-line databases of Scopus, Web of Science, PubMed/Medline, ProQuest, Science Direct, Magiran, SID and the search engine Google Scholar. The keywords of Phenylketonuria, PKU, Phenylalanine Hydroxylase, PAH, and Iran, as well as their Persian equivalents, in all possible combinations were used. Finally, a total of 21 eligible articles with a sample size of 1547 Iranian PKU patients, published between 2003 and 2020, were included in our systematic review. A total of 129 different PAH gene mutations including, IVS10-11G > A (c.1066-11G > A) (19.23%), p.R261Q (c.782G > A) (7.63%), p.P281L (c.842C > T) (6.24%), IVS2 + 5G > C (c.168 + 5G > C) (5.75%), p.R243* (c.727C > T) (3.59%), IVS9 + 5G > A (c.969 + 5G > A) (2.84%), p.R176* (c.526C > T) (2.42%), p.Lys363Nfs*37 (c.1089delG) (2.13%), IVS11 + 1G > C (c.1199 + 1G > C) (2.07%) and p.L48S (c.143 T > C) (2.04%) were identified. The spectrum and frequency of mutations observed in Iran were closer to those observed in the Mediterranean countries. Our results are valuable in planning panel-based studies in provinces with incomplete data on PAH gene mutations. This study is a good reference for genetic counselors and physicians who advise couples in making decisions to maintain or terminate a pregnancy.
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http://dx.doi.org/10.1007/s11011-021-00698-4DOI Listing
February 2021

Quantitative detection of SRY-Box 21 () gene promoter methylation as a stool-based noninvasive biomarker for early diagnosis of colorectal cancer by MethyLight method.

Indian J Cancer 2021 Jan 6. Epub 2021 Jan 6.

Department of Clinical Biochemistry, Kermanshah University of Medical Sciences, Kermanshah, Iran.

Background: In recent years, the study of potential epigenetic biomarkers in feces has been an attractive research approach for the noninvasive diagnosis of colorectal cancer (CRC). The aim of this study was to evaluate the stool-based DNA methylation potential of SRY-Box 21 (SOX21) gene promoter as an appropriate candidate biomarker for differentiating CRC patients and healthy individuals for the first time.

Methods: The MethyLight method was performed to analyze the methylation status of SOX21 gene promoter in fecal samples from 40 patients with CRC and 40 healthy controls. In addition, the diagnostic efficiency of measuring the hypermethylated SOX21 gene in the feces to the fecal occult blood test (FOBT) was compared.

Results: The percentage of methylated reference (PMR) values in the stool of CRC patients (median 1.44) was higher than those of healthy individuals (median 0.00) (P < 0.001). A sensitivity of 72.5% and specificity of 100% were obtained for SOX21 gene promoter methylation status and 29 of the patients were considered as positive in methylation status. There was no significant association between PMR values and demographic/clinicopathological features (P > 0.05).

Conclusion: The results of the present study demonstrated that the stool-based assay of SOX21 gene promoter methylation has a relatively high sensitivity and specificity and it may serve as a noninvasive biomarker for early detection of CRC. However, more studies with a wide range of samples are required to further confirm the role of hypermethylation of SOX21 in the early CRC diagnosis.
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http://dx.doi.org/10.4103/ijc.IJC_37_19DOI Listing
January 2021

Molecular Genetic Analysis of α-Thalassemia in Hamadan Province, West Iran.

Hemoglobin 2020 Sep 6;44(5):319-324. Epub 2020 Sep 6.

Department of Biochemistry, School of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Kermanshah Province, Iran.

Identifying couples who are carriers of thalassemia-causing mutations, followed by prenatal diagnosis (PND), is undoubtedly an effective way to prevent the birth of children with the disease. Our aim in this study was to report for the first time the spectrum of α-globin gene mutations in the population living in Hamadan Province, West Iran. Multiplex gap-polymerase chain reaction (gap-PCR), amplification refractory mutation system (ARMS)-PCR, and direct DNA sequencing of and genes were used to identify the α-thalassemia (α-thal)-causing mutations in a cohort of 389 individuals including 328 α-thal carriers and 61 normal subjects. A total of 17 different mutations and 25 different genotypes were detected. The -α (rightward) deletion (NG_000006.1: g.34164_37967del3804) was the most frequent mutation, accounting for more than half of all mutations (61.04%). This study revealed that there is a variety of α-thal mutations and α-thal genotypes in Hamadan Province, West Iran. This observation is probably due to the complexity of the Hamadan Province population that is composed of Persians (Fars), Turks, Kurds, and Lurs/Laks. In conclusion, our results demonstrated the spectrum of mutations in α-globin genes in Iran and increased our understanding of their distribution in this country.
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http://dx.doi.org/10.1080/03630269.2020.1800487DOI Listing
September 2020

Distribution of Gene Mutations in the Kurdish Population of Ilam Province, West Iran.

Hemoglobin 2020 Jul 1;44(4):244-248. Epub 2020 Sep 1.

Department of Biochemistry, School of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran.

β-Thalassemia (β-thal) is one of the most common diseases in Iran. Here, we report the spectrum of gene mutations in 176 Kurdish β-thal carriers from the northern part of Ilam Province, Iran. The amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) technique was used to identify common β-globin gene mutations observed in Iran. Samples negative on ARMS-PCR were analyzed by direct sequencing of the β-globin gene. In total, 12 different mutations were identified on the β-globin gene. The mutations of IVS-II-1 (G>A) (: c.315+1G>A), codons 8/9 (+G) (: c.27_28insG), codons 36/37 (-T) (: c.112delT) and IVS-I-110 (G>A) (: c.93-21G>A), were the most prevalent mutations in our samples, with frequencies of 59.09, 10.80, 7.95 and 7.39%, respectively. In general, the mutation spectrum of the β-globin gene in the northern part of Ilam Province is most similar to that in other western provinces of Iran. On the other hand, due to the high prevalence of carriers and β-thal major (β-TM) patients in this province, our results can be helpful in identifying carriers as well as at-risk fetuses through the prenatal diagnosis program.
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http://dx.doi.org/10.1080/03630269.2020.1797772DOI Listing
July 2020

The Spectrum of α-Thalassemia Mutations in Kurdistan Province, West Iran.

Hemoglobin 2020 May 26;44(3):156-161. Epub 2020 Jun 26.

Medical Genetics Laboratory, Kermanshah University of Medical Sciences, Kermanshah, Iran.

In order to identify the α-thalassemia (α-thal) mutation spectrum in Kurdistan Province, West Iran, a total of 217 individuals, including 154 α-thal carriers and 63 normal subjects were investigated in this study. Molecular analysis of α1- and α2-globin genes using multiplex gap-polymerase chain reaction (gap-PCR), amplification refractory mutation system (ARMS)-PCR or direct DNA sequencing, showed 11 different α-globin variants. The -α (rightward) deletion (NG_000006.1: g.34164_37967del3804) (70.32%), polyadenylation signal (polyA2) site (AATAA>AATAA) (αα) (: c.*92A>G) (7.74%), -α (leftward) deletion (6.45%) and codon 59 (or Hb Adana) (G>A) (αα) (: c.179G>A) (4.52%) were the most frequent mutations in the present study. In conclusion, the spectrum of α-thal mutations in Kurdistan Province is closest to that in western provinces of Iran (Kurdish and Laki populations). In addition, it was revealed that the codon 59 mutation is common in the Kurdish population. On the other hand, despite the same ethnic background of Kurds in Iran and Iraq, the - - double gene deletion and polyA2 point mutation have different distributions in these two populations. Therefore, further studies are needed to identify the cause of these differences.
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http://dx.doi.org/10.1080/03630269.2020.1768863DOI Listing
May 2020

Severe α-Thalassemia Due to Compound Heterozygosity for Hb Adana (α59 Gly>Asp) (: c.179G > A) and Codon 127 (A > T) (: c.382A > T) in an Iranian Family.

Hemoglobin 2020 Mar 5;44(2):139-142. Epub 2020 Jun 5.

Department of Biochemistry, School of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran.

We describe a novel compound heterozygous genotype which consists of two point mutations named Hb Adana (: c.179G>A) and codon 127 (: c.382A>T) in a Kurdish family with two girls affected with severe α-thalassemia (α-thal). Both patients (the proband and her sister) had a history of splenectomy during childhood. Although the proband had no blood transfusion history, her affected sister has had two blood transfusions so far. In conclusion, diagnosing and reporting new genotypes on the α-globin genes will improve our knowledge about complicated genotype-phenotype correlations in α-thal disorder.
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http://dx.doi.org/10.1080/03630269.2020.1766485DOI Listing
March 2020

High potential of gene promoter methylation as an epigenetic biomarker for early detection of colorectal cancer.

Indian J Cancer 2020 Apr-Jun;57(2):166-171

Department of Animal Biology, Faculty of Natural Science, University of Tabriz, Tabriz, Iran.

Background: Despite the advances in screening during the past decades, colorectal cancer (CRC) still is a leading cause of cancer deaths worldwide. Therefore, the development of new diagnostic methods is necessary.

Aim: The aim of this study was to compare methylation changes of SRY-Box 21 (SOX21) gene promoter in tumor tissues and their normal adjacent mucosa in patients with CRC and to examine the relationship between the methylation levels and demographic/clinicopathological factors.

Materials And Methods: A total of 41 CRC patients participated in the present study. After the extraction of DNA and bisulfite treatment of the samples, the methylation levels were determined by using the MethyLight method.

Statistical Analysis: Two-sided Mann-Whitney U test was used to compare the median level of methylation in tumor tissues and their adjacent normal mucosa.

Results: The methylation rates in tumor tissue samples were significantly higher compared to their adjacent normal mucosa (P < 0.0001). No association between demographic/clinicopathological factors and methylation status observed in tumor tissues. A receiver operating characteristics curve was constructed and tissue samples exhibited a sensitivity of 80.5% and specificity of 97.6% for SOX21 promoter methylation.

Conclusion: The results of this study indicated the high potential of SOX21 gene promoter methylation as a candidate noninvasive diagnostic biomarker in stool and plasma of colorectal cancer patients. However, further studies with larger sample sizes are required to evaluate the specific role of SOX21 methylation as a biomarker for early detection of CRC.
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http://dx.doi.org/10.4103/ijc.IJC_542_18DOI Listing
November 2020

α-Thalassemia Mutations in Ilam Province, West Iran.

Hemoglobin 2020 Feb 19:1-6. Epub 2020 Feb 19.

Department of Biochemistry, School of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran.

Despite several studies performed in different provinces of Iran to identify the spectrum of α-globin gene mutations, no such study has so far been carried out in Ilam Province. A total of 274 individuals, including 201 α-thalassemia (α-thal) carriers and 73 normal subjects, originating from the northern counties of Ilam Province, participated in this study. Analysis of α-globin defects was performed using multiplex gap-polymerase chain reaction (gap-PCR), amplification refractory mutation system (ARMS)-PCR and direct sequencing, which revealed a total of 11 different mutations and 22 different genotypes. The -α (rightward) (NG_000006.1: g.34164_37967del3804), αα (: c.95 + 2_95 + 6delTGAGG), and -α (leftward) deletions were the most prevalent mutations identified in our study, with frequencies of 66.23, 10.09 and 8.33%, respectively. In conclusion, the present study showed that the α-thal mutation spectrum in Ilam Province, at least in the northern part of the province, is different from that in other geographical regions of Iran. These results increase our knowledge about the spectrum and distribution of α-globin gene mutations in Iran.
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http://dx.doi.org/10.1080/03630269.2019.1694033DOI Listing
February 2020

The status of gene-VNTR alleles and mini-haplotypes associations with gene mutations in Iranian Kurdish PKU patients.

Med J Islam Repub Iran 2019 26;33:88. Epub 2019 Aug 26.

Infectious Disease Research Center, Kermanshah University of Medical Sciences, Kermanshah, Iran.

The analysis of haplotypes/mini-haplotypes in the gene has been used as an informative tool in several genetic anthropology studies. Considering the notion that Iranian population is one of the most heterogeneous i the world, this study was conducted to evaluate the association of VNTR-STR mini-haplotypes with the gene mutations in PKU patients in Kermanshah province. A total of 24 unrelated Kurdish PKU patients with the known gene causing mutations and 72 healthy controls were selected. The DNA fragments containing VNTR and STR systems were amplified by polymerase chain reaction (PCR). For VNTR system, PCR products were separated using electrophoresis on 2.5% agarose gel. For STR system, the samples were analyzed using DNA sequencing analysis version 5.2 software. Overall, 5 -VNTR-alleles, including VNTR3, 7, 8, 9, 12, and 3 -STR-alleles, including STR238, 242, and 250, were detected in this study. VNTR3 and 8 alleles had the most frequency among healthy controls. Also, 6 different mini-haplotype alleles were found to be associated with PKU chromosomes. The 2 most prevalent mutations in Kermanshah province, IVS2+5G>C and IVS9+5G>A, were strongly linked to mini-haplotypes 9/242 and 8/238, respectively. The distributions and frequencies of VNTR alleles in Kurdish population have the most similarity to alleles previously described in European Caucasian families. Moreover, since the most common mutations in Kermanshah PKU chromosomes are rare and this was the first study on mini-haplotypes VNTR/STR among Iranian Kurdish PKU patients, given that this study was the first of its kind, it was not possible to compare its results with that of other studies on Iranian and non-Iranian populations.
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http://dx.doi.org/10.34171/mjiri.33.88DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6825400PMC
August 2019

A comprehensive knowledge base of synaptic electrophysiology in the rodent hippocampal formation.

Hippocampus 2020 04 31;30(4):314-331. Epub 2019 Aug 31.

Neuroscience Program, Krasnow Institute for Advanced Study, George Mason University, Fairfax, Virginia.

The cellular and synaptic architecture of the rodent hippocampus has been described in thousands of peer-reviewed publications. However, no human- or machine-readable public catalog of synaptic electrophysiology data exists for this or any other neural system. Harnessing state-of-the-art information technology, we have developed a cloud-based toolset for identifying empirical evidence from the scientific literature pertaining to synaptic electrophysiology, for extracting the experimental data of interest, and for linking each entry to relevant text or figure excerpts. Mining more than 1,200 published journal articles, we have identified eight different signal modalities quantified by 90 different methods to measure synaptic amplitude, kinetics, and plasticity in hippocampal neurons. We have designed a data structure that both reflects the differences and maintains the existing relations among experimental modalities. Moreover, we mapped every annotated experiment to identified potential connections, that is, specific pairs of presynaptic and postsynaptic neuron types. To this aim, we leveraged Hippocampome.org, an open-access knowledge base of morphologically, electrophysiologically, and molecularly characterized neuron types in the rodent hippocampal formation. Specifically, we have implemented a computational pipeline to systematically translate neuron type properties into formal queries in order to find all compatible potential connections. With this system, we have collected nearly 40,000 synaptic data entities covering 88% of the 3,120 potential connections in Hippocampome.org. Correcting membrane potentials with respect to liquid junction potentials significantly reduced the difference between theoretical and experimental reversal potentials, thereby enabling the accurate conversion of all synaptic amplitudes to conductance. This data set allows for large-scale hypothesis testing of the general rules governing synaptic signals. To illustrate these applications, we confirmed several expected correlations between synaptic measurements and their covariates while suggesting previously unreported ones. We release all data open-source at Hippocampome.org in order to further research across disciplines.
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http://dx.doi.org/10.1002/hipo.23148DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7875289PMC
April 2020

The Spectrum of α-Thalassemia Mutations in the Lak Population of Iran.

Hemoglobin 2019 Mar;43(2):107-111

d Department of Biochemistry, School of Medicine , Kermanshah University of Medical Sciences , Kermanshah , Iran.

α-Thalassemia (α-thal) is one of the most common genetic disorders worldwide. The aim of this study was to investigate for the first time the α-thal mutation spectrum in the Lak population living in Lorestan Province, Iran. One hundred and seventy-six α-thal carriers participated in the study. Multiplex gap-polymerase chain reaction (gap-PCR), amplification refractory mutation system (ARMS)-PCR and direct sequencing were used for the detection of different mutations on the α-globin ( and ) genes. A total of 11 different mutations was identified. The -α (rightward; NG_000006.1: g.34164_37967del3804) deletion was observed most frequently (56.35%), followed by αα (: c.95+2_95+6delTGAGG), αα (: c.*92A>G) and - - (NG_000006.1: g.24664_41064del16401), with frequencies of 15.47, 9.39, and 6.08%, respectively. These four mutations accounted for more than 87.0% of the total mutated alleles. Moreover, 19 different genotypes were identified. The types and distribution pattern of the mutations identified in this study, in comparison with other studies conducted in Iran, was most similar to the Kurdish population of Kermanshah Province, Iran. Due to the lack of information on α-thal in Lorestan Province, it was not possible to compare the mutation spectrum in the Lur and Lak populations. In conclusion, our results may help in setting up a strategy for an α-thal screening program and genetic counseling in the Lak people.
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http://dx.doi.org/10.1080/03630269.2019.1614049DOI Listing
March 2019

The Spectrum of β-Thalassemia Mutations in Hamadan Province, West Iran.

Hemoglobin 2019 Jan 16;43(1):18-22. Epub 2019 May 16.

d Medical Genetics Laboratory , Kermanshah University of Medical Sciences , Kermanshah , Iran.

β-Thalassemia (β-thal) is one of the most common hemoglobinopathies worldwide and is caused by mutations on the β-globin () gene. The aim of the present study was to determine the mutation spectrum of the β-globin gene in β-thal carriers who were originally from Hamadan Province, Western Iran. Two hundred and eighty-two β-thal carriers participated in the study. Amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) and direct sequencing were used for detection of different mutations. A total of 25 different mutations, including 21 β-thal mutations and four other hemoglobin (Hb) variants, in 280 β-thal carriers (99.3%) were detected in the present study. Three types of mutations including IVS-II-1 (G>A) (: c.315+1G>A) (26.24%), codons 8/9 (+G) (: c.27_28insG) (14.54%) and codons 36/37 (-T) (: c.112delT) (12.76%) accounted for more than 50.0% of the identified mutations. Moreover, IVS-I-110 (G>A) (: c.93-21G>A), codon 44 (-C) (: c.135delC) and IVS-I (25 bp deletion) (: c.93-21_del), had frequencies of 7.09, 7.09 and 5.67%, respectively. Allele frequencies of the remaining 19 mutations were less than 5.0%. This study is the first comprehensive study on a large sample size in Hamadan Province, Iran. In conclusion, the present study significantly increased the spectrum of gene mutations in Hamadan Province compared with previous studies. Therefore, these results can be helpful in identifying β-thal carriers and at-risk fetuses through prenatal diagnosis (PND).
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http://dx.doi.org/10.1080/03630269.2019.1584114DOI Listing
January 2019

Spectrum of Phenylalanine Hydroxylase Gene Mutations in Hamadan and Lorestan Provinces of Iran and Their Associations with Variable Number of Tandem Repeat Alleles.

Iran J Med Sci 2018 May;43(3):318-323

Medical genetics laboratory, Kermanshah University of Medical Sciences, Kermanshah, Iran.

Phenylketonuria (PKU) is one of the most common known inherited metabolic diseases. The present study aimed to investigate the status of molecular defects in phenylalanine hydroxylase () gene in western Iranian PKU patients (predominantly from Kermanshah, Hamadan, and Lorestan provinces) during 2014-2016. Additionally, the results were compared with similar studies in Iran. Nucleotide sequence analysis of all 13 exons and their flanking intronic regions of the gene was performed in 18 western Iranian PKU patients. Moreover, a variable number of tandem repeat (VNTR) located in the gene was studied. The results revealed a mutational spectrum encompassing 11 distinct mutations distributed along the gene sequence on 34 of the 36 mutant alleles (diagnostic efficiency of 94.4%). Also, four VNTR alleles (with repeats of 3, 7, 8 and 9) were detected. The three most frequent mutations were IVS9+5G>A, IVS7-5T>C, and p.P281L with the frequency of 27.8%, 11%, and 11%, respectively. The results showed that there is not only a consanguineous relation, but also a difference in characters of mutations between Kermanshah and the other two parts of western Iran (Hamadan and Lorestan). Also, it seems that the spectrum of mutations in western Iran is relatively distinct from other parts of the country, suggesting that this region might be a special gene distribution region. Moreover, our findings can be useful in the identification of genotype to phenotype relationship in patients, and provide future abilities for confirmatory diagnostic testing, prognosis, and predict the severity of PKU patients.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5993902PMC
May 2018

Weighing the Evidence in Peters' Rule: Does Neuronal Morphology Predict Connectivity?

Trends Neurosci 2017 02 29;40(2):63-71. Epub 2016 Dec 29.

Kransnow Institute for Advanced Study, George Mason University, Fairfax, VA 22030, USA. Electronic address:

Although the importance of network connectivity is increasingly recognized, identifying synapses remains challenging relative to the routine characterization of neuronal morphology. Thus, researchers frequently employ axon-dendrite colocations as proxies of potential connections. This putative equivalence, commonly referred to as Peters' rule, has been recently studied at multiple levels and scales, fueling passionate debates regarding its validity. Our critical literature review identifies three conceptually distinct but often confused applications: inferring neuron type circuitry, predicting synaptic contacts among individual cells, and estimating synapse numbers within neuron pairs. Paradoxically, at the originally proposed cell-type level, Peters' rule remains largely untested. Leveraging Hippocampome.org, we validate and refine the relationship between axonal-dendritic colocations and synaptic circuits, clarifying the interpretation of existing and forthcoming data.
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http://dx.doi.org/10.1016/j.tins.2016.11.007DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5285450PMC
February 2017

Is "capacitive coupling" purely excitatory in the cardiac tissue?

Front Physiol 2014 25;5:77. Epub 2014 Mar 25.

Department of Cardiac Electrophysiology, Cardiac Electrophysiology Research Center, Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences Tehran, Iran.

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http://dx.doi.org/10.3389/fphys.2014.00077DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3971186PMC
April 2014

Bifurcation analysis of "synchronization fluctuation": a diagnostic measure of brain epileptic states.

Front Comput Neurosci 2014 6;8:11. Epub 2014 Feb 6.

Cybernetics and Modeling of Biological Systems Laboratory, Biomedical Engineering Faculty, Amirkabir University of Technology Tehran, Iran.

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http://dx.doi.org/10.3389/fncom.2014.00011DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3915881PMC
February 2014

Does "crisis-induced intermittency" explain bipolar disorder dynamics?

Front Comput Neurosci 2013 23;7:116. Epub 2013 Aug 23.

Biomedical Engineering Faculty, Amirkabir University of Technology Tehran, Iran.

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http://dx.doi.org/10.3389/fncom.2013.00116DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3750208PMC
August 2013

A fast model of voltage-dependent NMDA receptors.

J Comput Neurosci 2013 Jun 7;34(3):521-31. Epub 2012 Dec 7.

Neuroscience Research Center, Baqyatallah (a.s.) Medical Sciences University, Tehran, Iran.

NMDA receptors are among the crucial elements of central nervous system models. Recent studies show that both conductance and kinetics of these receptors are changing voltage-dependently in some parts of the brain. Therefore, several models have been introduced to simulate their current. However, on the one hand, kinetic models-which are able to simulate these voltage-dependent phenomena-are computationally expensive for modeling of large neural networks. On the other hand, classic exponential models, which are computationally less expensive, are not able to simulate the voltage-dependency of these receptors, accurately. In this study, we have modified these classic models to endow them with the voltage-dependent conductance and time constants. Temperature sensitivity and desensitization of these receptors are also taken into account. We show that, it is possible to simulate the most important physiological aspects of NMDA receptor's behavior using only three to four differential equations, which is significantly smaller than the previous kinetic models. Consequently, it seems that our model is both fast and physiologically plausible and therefore is a suitable candidate for the modeling of large neural networks.
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http://dx.doi.org/10.1007/s10827-012-0434-4DOI Listing
June 2013