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1.  Post Neurosurgical Meningitis due to Colistin Heteroresistant Acinetobacter baumannii 
Recently Acinetobacter baumannii isolates have emerged as a problematic infectious agent that causes meningitis in neurosurgical patients. Colistin has been used successfully for the treatment of A. baumannii meningitis but colistin resistant isolates have been reported worldwide.
Case Presentation:
Two isolates of A. baumannii were cultured during a five-day period from cerebrospinal fluid (CSF) samples of a 20-year-old man with a gunshot trauma in the abdomen, which had exited from his back. Antimicrobial susceptibility tests of isolates were performed. Multiplex PCR was performed for detection of blaOXA-23-like, blaOXA-24-like and blaOXA-58-like genes. Metallo-β-lactamase genes such as: blaVIM, blaIMP, blaSPM and blaNDM were sought by singleplex PCR. In order to evaluate the genetic relationship, two isolates were examined by the repetitive extragenic palindromic-polymerase chain reaction (REP_PCR) method.
E-test results showed that the isolates were sensitive to colistin and tigecycline with minimum inhibitory concentration of (MIC) 0.25 µg/mL and 1.5 µg/mL, respectively. Secondly the isolates were resistant to colistin with MIC > 256 µg/mL but remained sensitive to tigecycline with MIC 1.5 µg/mL. On the basis of the multiplex PCR, both of the isolates were positive for blaOXA-23-like. Other investigated genes such as blaOXA-24-like, blaOXA-58-like, blaVIM, blaIMP, blaSPM and blaNDM were negative. REP-PCR results showed that two isolates were derived from a single strain and both were the same. The results of our study revealed that the firs isolate of A. baumannii was colistin heteroresistant and was changed to completely resistant during therapy. Diagnosis and treatment of A. baumannii meningitis is very important and to avoid treatment failure we suggest that all A. baumannii isolates obtained from CSF should be evaluated properly for colistin heteroresistance.
PMCID: PMC4295316  PMID: 25632326
Acinetobacter baumannii; Meningitis; Colistin; Neurosurgery
2.  Lack of Association between ESR1 and CYP1A1 Gene Polymorphisms and Susceptibility to Uterine Leiomyoma in Female Patients of Iranian Descent  
Cell Journal (Yakhteh)  2014;16(2):225-230.
Uterine leiomyoma (UL) is the most common benign smooth muscle cell tumor with as yet unknown etiology and pathogenesis. This study was carried out to investigate the association of ESR1-351 A>G, ESR1 -397 T>C and CYP1A1 (Ile462Val) polymorphisms with UL in female patients of Iranian origin. In this case-control study, 276 patients with UL and 156 healthy women were recruited. The genetic polymorphisms ESR1-351 A>G, ESR1-397 T>C and CYP1A1 (Ile462Val) were genotyped by polymerase chain reaction- restriction fragment length polymorphism (PCR-RFLP). No significant difference were found in frequencies of both genotypes and alleles of ESR1-351 A>G, ESR1-397 T>C and CYP1A1 (Ile462Val) polymorphisms between the two groups (p>0.05). Our findings indicated that these ESR1 and CYP1A1 polymorphisms were not associated with the development of UL in the cases reported here.
PMCID: PMC4072073  PMID: 24567938
ESR1; CYP1A1; Uterine Leiomyoma; Polymorphism
3.  The Study of SLC26A4 Gene Causing Autosomal Recessive Hearing Loss by Linkage Analysis in a Cohort of Iranian Populations 
Sensorineural non-syndromic hearing loss is the most common disorder which affects 1 in 500 newborns. Hearing loss is an extremely heterogeneous defect with more than 100 loci identified to date. According to the studies, mutations in GJB2 are estimated to be involved in 50- 80% of autosomal recessive non-syndromic hearing loss cases, but contribution of other loci in this disorder is yet ambiguous. With regard to studies, DFNB4 locus (SLC26A4) can be classified as the second cause of hearing loss. So, this study aimed to determine the contribution of this locus in hearing loss as well as the frequency of SLC26A4 gene mutations in a population in the west of Iran. In this descriptive laboratory study, we included 30 families from the west of Iran with no mutation in GJB2 gene. Linkage analysis was performed by DFNB4 (SLC26A4) molecular markers (STR). The families with hearing loss linked to this locus were further analyzed for mutation detection. SLC26A4 gene exons were amplified and analyzed using direct DNA sequencing. In studied families, 2 families displayed linkage to DFNB4 locus. Identified mutations include mutation in exon 5 (c.416 G>T) and in splicing site of exon 7 (IVS-2 A>G or c.919-2 A>G).
PMCID: PMC4170491  PMID: 25317404
SLC26A4; hearing loss; linkage analysis; Iran
4.  The Role of Epigenetics in the Induction of Fetal Hemoglobin: A Combination Therapy Approach 
β-thalassemia considers worldwide public health disorders. Novel fetal hemoglobin inducer agents such as thalidomide and sodium butyrate have been attended for ameliorating clinical complications of such disorders.
Material and Methods
We used thalidomide and sodium butyrate for increasing the level of fetal hemoglobin in erythroid progenitors. Briefly, after isolation of CD133+ stem cells from umbilical cord blood and differentiation into erythroid lineage, erythroid progenitors were treated with thalidomide and sodium butyraye as single and combination. H3K4 histone methylation was evaluated following fetal hemoglobin induction using chromatin immuno percipitation (ChIP) technique.
The results of this study showed that the effect of thalidomide on increasing of H3K4 methylation was highest compared to sodium butyrate and combination of both agents (p < 0.05).
Consequently, our study of the epigenetic modification of the γ-globin suggests that histone H3K4 dimethylation are significant for the regulation of developmental stage-specific expression of the γ-globin genes.
PMCID: PMC3913159  PMID: 24505546
Thalidomide; Sodium butyrate; γ-globin; β-thalassemia
5.  Compound Heterozygosity for Two Novel SLC26A4 Mutations in a Large Iranian Pedigree with Pendred Syndrome 
The aim of this study was to detect the genetic cause of deafness in a large Iranian family. Due to the importance of SLC26A4 in causing hearing loss, information about the gene mutations can be beneficial in molecular detection and management of deaf patients.
We investigated the genetic etiology in a large consanguineous family with 9 deaf patients from Fars province of Iran with no GJB2 mutations. Initially, linkage analysis was performed by four DFNB4 short tandem repeat markers. The result showed linkage to DFNB4 locus. Following that, DNA sequencing of all 21 exons, their adjacent intronic sequences and the promoter of SLC26A4 was carried out for mutation detection.
Two novel mutations (c.863-864insT and c.881-882delAC) were identified in exon 7 of the gene, in both homozygous and compound heterozygous state in patients.
Our results supported the importance of the SLC26A4 mutations in the etiology of hearing loss among the Iranian patients and therefore its mutation screening should be considered after GJB2 in the molecular diagnostics of hearing loss, especially when enlarged vestibular aqueduct or goiter is detected.
PMCID: PMC3863667  PMID: 24353858
Novel mutation; Compound heterozygosity; SLC26A4; Pendred syndrome; Hearing loss; Linkage analysis; Iran
6.  UGT1A1 Gene Mutation due to Crigler-Najjar Syndrome in Iranian Patients: Identification of a Novel Mutation 
BioMed Research International  2013;2013:342371.
Crigler-Najjar syndrome (CNS) type I and type II are inherited as autosomal recessive conditions that are caused by mutations in the UGT1A1 gene. We present the analysis of UGT1A1 gene in 12 individuals from three different families. This analysis allowed us to identify one novel mutation, which was not previously described. In this study, three families with clinically diagnosed CNS referred from Khuzestan province, southwest Iran, were screened. After signing the informed consent, peripheral blood samples from the patients and their parents were collected in EDTA-containing tube followed by DNA extraction using a routine phenol-chloroform method. All five coding exons and the flanking intronic regions of the bilirubin-UGT were amplified by polymerase chain reaction (PCR) followed by DNA sequencing by Sanger method. From the first family, a 9-month-old boy was homozygous for a deletion mutation of two adjacent nucleotides including one adenosine (A) and one glutamine (G) between nucleotides 238 and 239 in exon 1 (c.238_240 del AG). In the second family, there were two affected individuals, an 11-year-old girl and a fetus, found to be homozygous for the same mutation. The third family showed a mutation at nucleotide 479 in exon 1 (Val160Glu) that has been reported previously. Molecular analysis can significantly help confirm the diagnosis of CNS, without any need for the liver biopsy, and may help the therapeutic management by ruling out more harmful causes of hyperbilirubinemia.
PMCID: PMC3826477  PMID: 24286076
7.  Identification of Xq22.1-23 as a region linked with hereditary recurrent spontaneous abortion in a family 
Background: Recurrent spontaneous abortion (RSA) is one of the most common health complications with a strong genetic component. Several genetic disorders were identified as etiological factors of hereditary X linked RSA. However, more genetic factors remain to be identified.
Objective: In this study we performed linkage analysis on a large X linked RSA pedigree to find a novel susceptibility locus for RSA.
Materials and Methods: A linkage scan using 11 microsatellites was performed in 27 members of a large pedigree of hereditary X-linked RSA. Two point parametric Linkage was performed using Superlink v 1.6 program.
Results: Evidence of linkage was observed to markers at Xq23, DXS7133 and at Xq22.1 DXS101, with LOD score of 3.12 and 1.60, respectively.
Conclusion: Identified locus in this study may carry a responsible gene in RSA. Narrowing down of this region may leads to identification of this gene.
This article extracted from M.Sc. thesis. (Sahar Shekouhi)
PMCID: PMC3941371  PMID: 24639804
X-linked; Recurrentspontaneousabortion; Linkage
8.  Molecular diagnostics for congenital hearing loss including 15 deafness genes using a next generation sequencing platform 
BMC Medical Genomics  2012;5:17.
Hereditary hearing loss (HL) can originate from mutations in one of many genes involved in the complex process of hearing. Identification of the genetic defects in patients is currently labor intensive and expensive. While screening with Sanger sequencing for GJB2 mutations is common, this is not the case for the other known deafness genes (> 60). Next generation sequencing technology (NGS) has the potential to be much more cost efficient. Published methods mainly use hybridization based target enrichment procedures that are time saving and efficient, but lead to loss in sensitivity. In this study we used a semi-automated PCR amplification and NGS in order to combine high sensitivity, speed and cost efficiency.
In this proof of concept study, we screened 15 autosomal recessive deafness genes in 5 patients with congenital genetic deafness. 646 specific primer pairs for all exons and most of the UTR of the 15 selected genes were designed using primerXL. Using patient specific identifiers, all amplicons were pooled and analyzed using the Roche 454 NGS technology. Three of these patients are members of families in which a region of interest has previously been characterized by linkage studies. In these, we were able to identify two new mutations in CDH23 and OTOF. For another patient, the etiology of deafness was unclear, and no causal mutation was found. In a fifth patient, included as a positive control, we could confirm a known mutation in TMC1.
We have developed an assay that holds great promise as a tool for screening patients with familial autosomal recessive nonsyndromal hearing loss (ARNSHL). For the first time, an efficient, reliable and cost effective genetic test, based on PCR enrichment, for newborns with undiagnosed deafness is available.
PMCID: PMC3443074  PMID: 22607986
Deafness; Next generation sequencing; PCR based enrichment; Genetic diagnostics
9.  Association of the TCF7L2 rs12255372 (G/T) variant with type 2 diabetes mellitus in an Iranian population 
Genetics and Molecular Biology  2012;35(2):413-417.
In various populations worldwide, common variants of the TCF7L2 (Transcription factor 7-like 2) gene are associated with the risk of type 2 diabetes mellitus (T2DM). The aim was to investigate the association between rs12255372 (G/T) polymorphism in the TCF7L2 gene and T2DM in an Iranian population. 236 unrelated patients with T2DM, and 255 normoglycemic controls without diabetes were studied. The PCR-RFLP method was used for genotyping rs12255372 (G/T) polymorphism, and the SPSS version 18.0 for Windows for statistical analysis. The minor T allele of TCF7L2 rs12255372 was found to significantly increase the risk of T2DM, with an allelic odds ratio (OR) of 1.458 (95% CI 1.108–1.918, p = 0.007). A significant difference in TT genotype was observed between T2DM patients and normoglycemic controls (OR 2.038, 95% CI 1.147–3.623; p = 0.014). On assuming dominant and recessive models, ORs of 1.52 [95% CI (1.05–2.21) p = 0.026)] and 1.74 [95% CI (1.01–3.00) p = 0.043] were obtained, respectively, thereby implying that the co-dominant model would best fit the susceptible gene effect. This study further confirms the TCF7L2 gene as enhancing susceptibility to the development of T2DM.
PMCID: PMC3389527  PMID: 22888288
TCF7L2 gene; rs12255372 variant; type 2 diabetes mellitus (T2DM); single nucleotide polymorphism (SNP)

Results 1-9 (9)