Analysis of Programmed Cell Death-1 (PD-1) Gene Variations (re11568821 and rs41386349) in HTLV-1 Infection Using One Primer Pair and Proviral Load.

About 90% of people infected with Human T lymphotropic virus type-1 (HTLV-1) virus are asymptomatic, so it can be said that the prevalence of this virus is not completely clear. During chronic infection, the expression of programmed cell death-1 (PD-1) protein increases and causes exhausted phenotype in T cells. Considering the role of host genetics and immune responses in HTLV-1 infection, in this case-control study, included 81 asymptomatic carriers (ACs) and 162 healthy controls (HCs), rs11568821 and rs41386349 polymorphisms of PD-1 gene were evaluated by Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method which investigated by one primer pair for both polymorphisms also, proviral load (PVL) measured by quantitative real-time PCR (Q-RT-PCR). The results showed that the mutant allele of rs11568821 (A) and rs41386349 (T) polymorphisms is associated with an increase in HTLV-1 infection significantly (p = 0.019 and p = 0.000 respectively). But there was no significant relationship between PVL and polymorphisms.

Accessible high-performance double nanohole tweezers.

Nanohole optical tweezers have been used by several groups to trap and analyze proteins. In this work, we demonstrate that it is possible to create high-performance double nanohole (DNH) substrates for trapping proteins without the need for any top-down approaches (such as electron microscopy or focused-ion beam milling). Using polarization analysis, we identify DNHs as well as determine their orientation and then use them for trapping. We are also able to identify other hole configurations, such as single, trimers and other clusters. We explore changing the substrate from glass to polyvinyl chloride to enhance trapping ability, showing 7 times lower minimum trapping power, which we believe is due to reduced surface repulsion. Finally, we present tape exfoliation as a means to expose DNHs without damaging sonication or chemical methods. Overall, these approaches make high quality optical trapping using DNH structures accessible to a broad scientific community.

Association of the rs4143815 polymorphism of PDL1 gene with HTLV-1 infection and proviral load in asymptomatic blood donors in northeast Iran.

It is obvious that genetic differences, including mutations and polymorphisms, can play an important role in viral infections. In this case-control study, which included 81 human T-cell leukemia virus type 1 (HTLV-1) asymptomatic carriers (AC) and 162 healthy controls (HC), the rs4143815 polymorphism of PDL1 gene was investigated. This polymorphism is the site of miR-570 binding and it can influence immune system responses. The rs4143815 polymorphism was evaluated by allele-specific polymerase chain reaction (AS-PCR) and the proviral load levels by quantitative real-time PCR (q PCR). The results demonstrated that the C allele (P = 0.027) and the CC genotype (P = 0.031) of rs4143815 polymorphism was significantly higher in the AC group than in the HC group, also the proviral load in the AC group with the C allele (P = 0.020) was significantly higher. Thus, the rs4143815 polymorphism can play a vital role in HTLV-1 infection.

Quantification of hepatitis C virus in viremic blood donors in Iran: Need to reinforce post-donation follow up.

INTRODUCTION: Hepatitis C virus (HCV) infection is a public health problem and a major cause of chronic liver disease around the world. The main route of HCV transmission is contact with small quantities of infectious blood. Knowledge of the distribution of HCV viral load is essential to control HCV infection. This study aimed to investigate the HCV viral load distribution among Iranian blood donors. MATERIALS AND METHODS: This cross-sectional study was conducted on 160 HCV confirmed blood donors with detectable HCV RNA who referred to blood transfusion centers for post-donation counseling all over the country. HCV RNA was quantified using an in-house one-step real-time reverse transcription-polymerase chain reaction (RT-PCR) kit. Statistical analysis was performed in STATA version 13. RESULTS: The mean age of the participants was 37.66 years. Out of 160 subjects, 156 (97.5 %) were male. The median viral load of the subjects was 7.7 × 104 (range: 2.28 × 10 3-3.42 × 107 IU/mL). Out of 160 blood donors, 70 (43.75 %, 95 % CI 0.36-0.51) had a viral load ≤5 × 104 IU/mL, and 90 (56.25 %, 95 % CI: 0.49-0.64) had a viral load >5 × 104 IU/mL. DISCUSSION: The distribution of HCV viral load among viremic blood donors emphasizes on the role of post-donation follow up in identification of blood donors potentially need for HCV anti-viral therapies.

A decade of molecular preimplantation genetic diagnosis of 350 blastomeres for beta-thalassemia combined with HLA typing, aneuploidy screening and sex selection in Iran.

BACKGROUND: Preimplantation genetic diagnosis (PGD) has been developed to detect genetic disorders before pregnancy which is usually done on blastomeres biopsied from 8-cell stage embryos obtained from in vitro fertilization method (IVF). Here we report molecular PGD results for diagnosing of beta thalassemia (beta-thal) which are usually accompanied with evaluating chromosomal aneuploidies, HLA typing and sex selection. METHODS: In this study, haplotype analysis was performed using short tandem repeats (STRs) in a multiplex nested PCR and the causative mutation was detected by Sanger sequencing. RESULTS: We have performed PGDs on 350 blastomeres from 55 carrier couples; 142 blastomeres for beta-thal only, 75 for beta-thal and HLA typing, 76 for beta-thal in combination with sex selection, and 57 for beta-thal and aneuploidy screening. 150 blastomeres were transferable, 15 pregnancies were happened, and 11 babies born. We used 6 markers for beta-thal, 36 for aneuploidy screening, 32 for sex selection, and 35 for HLA typing. To our knowledge combining all these markers together and the number of STR markers are much more than any other studies which have ever done. CONCLUSIONS: PGD is a powerful diagnostic tool for carrier couples who desire to have a healthy child and wish to avoid medical abortion.

The association of polymorphisms (rs2227981 and rs10204525) of PDCD1 gene with susceptibility to human T-cell leukemia virus type 1.

Human T-cell leukemia virus type 1 (HTLV-1) is the first retrovirus as the causative agent of two serious diseases in human is known. Programmed cell death-1 (PD-1) is a regulatory protein that has an important role in immune system response and created exhaustion phenotype in T cells at chronic infections; therefore, it can impair anti-viral responses. Since the single nucleotide polymorphisms (SNP) in PD-1gene may influence infection with HTLV-1virus, so in this research, association between SNPs in exon 5 of PD-1 gene with susceptibility to HTLV-1 infection and proviral load (PVL) in Iran's population studied. In this case-control study, PD-1 rs2227981 and rs10204525 polymorphisms were evaluated in 81 HTLV-1 asymptomatic carriers (ACs) and 162 healthy individuals (control groups). These polymorphisms were genotyped by Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Moreover, PVL was detected by quantitative real-time PCR (Q-RT-PCR). The results indicated that frequency of GA and AA genotypes in rs10204525 polymorphism was higher in ACs group (82.7%) than control group (26.5%) significantly; and GA + AA genotypes were significantly associated with HTLV-1 infection (OR = 13.244, 95%CI = 6.755-25.968, p = 0.000); but CT + TT genotypes in rs2227981 polymorphism, were as a protective factor against HTLV-1 infection (OR = 0.473, 95%CI = 0.279-0.813, P = 0.009). However, there was no significant difference between these polymorphisms and HTLV-1 PVL.

Isolating and enhancing single-photon emitters for 1550 nm quantum light sources using double nanohole optical tweezers.

Single-photon sources are required for quantum technologies and can be created from individual atoms and atom-like defects. Erbium ions produce single photons at low-loss fiber optic wavelengths, but they have low emission rates, making them challenging to isolate reliably. Here, we tune the size of gold double nanoholes (DNHs) to enhance the emission of single erbium emitters, achieving 50× enhancement over rectangular apertures previously demonstrated. This produces enough enhancement to show emission from single nanocrystals at wavelengths not seen in our previous work, i.e., 400 and 1550 nm. We observe discrete levels of emission for nanocrystals with low numbers of emitters and demonstrate isolating single emitters. We describe how the trapping time is proportional to the enhancement factor for a given DNH structure, giving us an independent way to measure the enhancement. This shows a promising path to achieving single emitter sources at 1550 nm.

Prevalence of Hepatitis B Virus Infection Among Voluntary Blood Donors from the Northeastern Region of Iran: Genotyping, Viral Load Characterization and Drug Resistance Prediction.

BACKGROUND: Blood donor selection, along with laboratory screening of the HBV, plays a pivotal role in providing safe blood products. This study was aimed to evaluate the prevalence, genotype, and drug resistance prediction of HBV among Iranian blood donors. METHODS: This cross-sectional study was conducted on 47,506 blood donors referring to Golestan Blood Center from March 21, 2018, to March 20, 2019. Siemens Enzyngnost HBsAg6, INNO-LiPA Genotyping kits, and Nest-PCR were used for HBV screening, genotyping, and amplification of the polymerase gene, respectively. An online tool at hbv.geno2pheno.org and real-time PCR method were also utilized for drug resistance prediction and viral load measurement respectively. RESULTS: It was found that from among 47,506 donors, 47 (0.09%) were confirmed to be HBV positive subjects. About 0.94% of first-time blood donors (46 out of 4, 872) and 0.008% of repeated blood donors (1 out of 12,125) were found to be positive for HBV. First-time blood donors were also 8.6 times more likely to have a hepatitis B virus infection (odds ratio: 9.6; 95% confidence interval, 6.2 - 14.7). Seven donors had genotype D as predominant and one case had a mixed infection with genotypes A and D. Furthermore, the most predicted mutation in the polymerase gene was m204V, causing resistance to telbivudine and lamivudine. CONCLUSIONS: The results showed that the risk of HBV transmission is higher among first-time blood donors. Therefore, it is recommended that predonation laboratory screening in first-time blood donors be conducted to improve the safety of the donated blood in the studied region.

Correlation of serum microRNA-122 level with the levels of Alanine aminotransferase and HBV-DNA in Chronic HBV-infected patients.

Background: The microRNA-122 (miR-122) is a liver-specific microRNA that can be used as a potential molecular marker for predicting liver injury. There is a positive correlation between miR-122 level in serum and hepatitis B virus (HBV) replication in patients infected with this virus. The present study was conducted to study the clinical importance and expression of miR-122 in asymptomatic and symptomatic patients with HBV infection in comparison to the healthy group. Methods: This study was performed on 60 samples to examine the presence of HBsAg and total HBc antibody (IgM-IgG) using an enzyme-linked immunosorbent assay. HBV-DNA extraction and real time polymerase chain reaction (PCR) assay were performed on all samples via the Real ART HBV LC PCR kit on a LightCycler instrument. RNA was extracted from the serum of all participants. Next, miRNA expression was assessed using quantitative real time reverse-transcription PCR. Also, ALT levels were measured as a surrogate parameter for liver injury using Pars Azmoon Biochemical assay Kit on Hitachi autoanalyzer. The Levene, Kruskal Wallis, Mann-Whitney and Spearman's correlation tests were used for assessing the differences between the studied groups. Results: Based on the obtained results, miR-122 expression in patients with HBV without clinical symptoms was 1.6 times, while in patients with clinical symptoms was 2.7 times more than the control group (p=0.001). A significant increase was observed in the ALT enzyme of symptomatic patients (p=0.001). HBV DNA in the people with clinical symptoms was higher than 105 copies/mL and in the asymptomatic group was less than 103 copies/mL, suggesting a statistically significant increase in a group with clinical symptoms (p=0.001). Finally, it was found that the miR-122 serum concentration correlated with HBV DNA and serum ALT (p=0.001). Conclusion: Based on the obtained results, measuring the miR-122 levels can serve as a biomarker and an indicator of hepatitis B replication, especially in cases where ALT levels are unchanged; however, more research and more samples are needed.

Maple syrup urine disease mutation spectrum in a cohort of 40 consanguineous patients and insilico analysis of novel mutations.

Maple syrup urine disease is the primary aminoacidopathy affecting branched-chain amino acid (BCAA) metabolism. The disease is mainly caused by the deficiency of an enzyme named branched-chained α-keto acid dehydrogenase (BCKD), which consist of four subunits (E1α, E1ß, E2, and E3), and encoded by BCKDHA, BCKDHB, DBT, and DLD gene respectively. BCKD is the main enzyme in the catabolism pathway of BCAAs. Hight rate of autosomal recessive disorders is expected from consanguineous populations like Iran. In this study, we selected two sets of STR markers linked to the four genes, that mutation in which can result in MSUD disease. The patients who had a homozygous haplotype for selected markers of the genes were sequenced. In current survey, we summarized our recent molecular genetic findings to illustrate the mutation spectrum of MSUD in our country. Ten novel mutations including c.484 A > G, c.834_836dup CAC, c.357del T, and c. (343 + 1_344-1) _ (742 + 1_743-1)del in BCKDHB, c.355-356 ins 7 nt ACAAGGA, and c.703del T in BCKDHA, and c.363delCT/c.1238 T > C, c. (433 + 1_434-1) _ (939 + 1_940-1)del, c.1174 A > C, and c.85_86ins AACG have been found in DBT gene. Additionally, structural models of MSUD mutations have been performed to predict the pathogenicity of the newly identified variants.

Characterization and haplotype study of 6 novel STR markers related to the KCNQ1 gene in heterogeneous cardiovascular disorders in the Iranian population

Background/aim: The KCNQ1 gene has a significant role in long QT syndrome, Jervell and Lange-Nielsen syndrome, familial atrial fibrillation, and short QT syndrome. Analyzing such heterogeneous disorders, six novel short tandem repeat (STR) markers around the KCNQ1 gene were found and evaluated in a healthy population, and other statistical traits of the markers were detected. Materials and methods: Using Tandem Repeats Finder (TRF) and Sequence-Based Estimation of Repeat Variability (SERV) software, STR markers were detected with valid tetra- and pentanucleotide repeats. The markers were investigated for a total of 60 unrelated Iranian healthy individuals and analyzed using GenAlEx 6.502 and Cervus 3.0.7. Results: A total of 77 haplotypes was detected, of which 25 haplotypes were unique and the others occurred at least two times. The number of haplotypes per locus ranged from 7 to 18 with the highest frequency of 69.2%, and the observed heterozygosity was calculated as 0.589. The power of discrimination ranged from 0.70 to 0.96. Five of the markers meet Hardy­Weinberg equilibrium. Conclusion: A novel panel of STR markers was described with high allele heterozygosity and segregation in every locus, which may lead to faster and more credible recognition of the disease-inducing KCNQ1 gene and allow it to be used for human identity testing and prenatal diagnosis.

Role of platelet-derived microparticles in transfer of the chemokine receptor CXCR4 to CXCR4-negative cells.

Background: Membrane-derived microparticles (PMPs) are produced from platelets during activation, storage, and apoptosis. PMP can transfer some adhesion molecules such as CXCR4 to CXCR4-negative cells. In this study, the ability of PMPs to deliver CXCR4 molecule to CXCR4-null targets (Daudi, K562 and U937 cell line) was evaluated and the different concentrations of PMPs were examined to transfer CXCR4. Methods: In this experimental study, PMPs were prepared using serial centrifugations. After confirmation of PMP with flow cytometry, PMP concentration was evaluated using the Bradford method. CXCR4-negative cell lines (1×105 cells/ml) were cultured in RPMI1640 with 10% FBS and 1% antibiotic. PMPs in 7 different concentrations were added to cell culture plates and incubated for 1 hour at 37ºc and 5% CO2. The presence of CXCR4 on cells was analyzed by flowcytometry. Results: In this study, characterization of PMPs and cell lines were done by flow cytometry. Then, the PMPs' ability to transfer CXCR4 to null cells (Daudi, K562 and U937 cell lines) was evaluated in 7 concentrations (10, 20, 50,125, 250, 500, 1000 µg/mL); incubation lasted for 1 hour. The best result of transferring CXCR4 by PMP was done in the concentration of 250µg/mL. Conclusion: PMPs in different concentrations can transfer CXCR4 to target cells. Also, the increase of PMPs concentration up to 250µg/mL can increase the CXCR4 presence on null cells.

Association of HCV genotype with viral load among Iranian blood donors: a penalized logistic regression.

Background: Hepatitis C virus (HCV) is a blood born virus and the leading cause of advanced hepatitis disease. HCV genotype 3a is predominant among Iranian blood donors. The aim of this study was to evaluate the relationship between HCV genotype and HCV viral load. Methods: In this analytical cross-sectional study 106 anti-HCV positive and HCV RNA positive blood donors referred to Iranian blood centers across the county were entered. HCV viral loads were determined by an in-house one step Taq Man Real-Time RT-PCR assay. Penalized logistic regression was performed for data analysis. STATA software version 13 was used for statistical analysis. Results: The mean age was 37.94 ± 9.04 years ranged from 19 to 58 years. Male gender included 104 (98.1%) of subjects. 31, 10 and 65 subjects were infected with genotypes1a, 1b, and 3a, respectively. The mean viral load was 1.44 × 106 ± 4.5× 105 IU/ml. HCV viral load was not significantly different among subjects infected with HCV genotypes 1, 1.49 × 10 6 ± 4.57 × 10 6 IU/ml compare to genotype 3, 1.40 × 10 6 ± 5.58 4.58 × 106 IU/ml (p=0.93). Conclusion: Although not significant, the frequency of subjects with high viral load (> 800,000 IU/ml) was higher in subjects infected with genotype 3 than those of genotype 1. No associations were found between demographic characteristics and HCV genotype. Although the study was unable to find any association between HCV genotype and HCV viral load/ HCV viral load group, it highlighted the role of high viral load in the high circulation of HCV genotype 3a among Iranian blood donors.

Phylogenetic analysis of HTLV-1 in Iranian blood donors, HIV-1 positive patients and patients with beta thalassemia.

Human T-cell lymphoma virus (HTLV) has been associated with various disease types. Since the discovery of the virus in 1980, seven subtypes of the virus have been identified. HTLV is widespread and endemic in some regions, such as Japan, Africa, South America, and northeast Iran. This study aimed to identify HTLV-1 genotype and also to analyze the nucleotide sequence of the LTR region in three groups, including blood donors, HIV-1+ patients, and ß-thalassemia patients. In this cross-sectional study, 2200 samples were collected from blood donors in Tehran (2000 samples), HIV-1+ patients (100 samples) and ß-thalassemia patients (100 samples). All samples were screened for anti-HTLV-I&II antibodies by ELISA. Then, genomic DNA was extracted from repeatedly positive samples, and nested PCR was performed for both the TAX and LTR regions. Purified PCR products were sequenced and analyzed, and finally, a phylogenetic tree was constructed using Mega7 software. The prevalence of the anti-HTLV-I&II antibody among blood donors and HIV-1+ patients was 1.7% (34/2000) and 12% (12/100), respectively. The PCR results confirmed that 0.05% (1/2000) of blood donors, 5% (5/100) of HIV-1+ patients, and 8% (8/100) of ß-thalassemia patients were HTLV-I positive. All sequences were matched to HTLV-1 subtype a, subgroup A. Our phylogenetic analysis revealed that all sequenced samples belong to the endemic clusters of Iran. HTLV-1 genotypes in all samples were similar in three groups and were derived from the strains, which had been previously reported from Iran (AF00300/Mashhad and KT190712.1/Sabzevar).

The first successful application of preimplantation genetic diagnosis for hearing loss in Iran.

Hearing impairment (HI) caused by mutations in the connexin-26 gene (GJB2) accounts for the majority of cases with inherited, nonsyndromic sensorineural hearing loss. Due to the illegality of the abortion of deaf fetuses in Islamic countries, preimplantation genetic diagnosis (PGD) is a possible solution for afflicted families to have a healthy offspring. This study describes the first use of PGD for GJB2 associated non-syndromic deafness in Iran. GJB2 donor splicing site IVS1+1G>A mutation analysis was performed using Sanger sequencing for a total of 71 Iranian families with at least 1 deaf child diagnosed with non-syndromic deafness. In Vitro Fertilization (IVF) was performed, followed by PGD for a cousin couple with a 50% chance of having an affected child. Bi-allelic pathogenic mutations were found in a total of 12 families (~17 %); of which a couple was a PGD volunteer. The deaf woman in this family was homozygous and her husband was a carrier of the IVS1+1G>A gene mutation. Among 8 biopsied embryos, two healthy embryos were implanted which resulted in a single pregnancy and subsequent birth of a healthy baby boy. This is the first report of a successful application of PGD for hearing loss in Iran. Having a baby with a severe hearing impairment often imposes families with long-term disease burden and heavy therapy costs. Today PGD has provided an opportunity for high-risk individuals to avoid the birth of a deaf child.

Overexpression of miR-183/-96/-182 triggers neuronal cell fate in Human Retinal Pigment Epithelial (hRPE) cells in culture.

miR-183 cluster, composed of miR-183/-96/-182 genes, is highly expressed in the adult retina, particularly in photoreceptors. It involves in development, maturation and normal function of neuroretina. Ectopic overexpression of miR-183/-96/-182 genes was performed to assess reprogramming of hRPE cells. They were amplified from genomic DNA and cloned independently or in tandem configuration into pAAV.MCS vector. hRPE cells were then transfected with the recombinant constructs. Real-Time PCR was performed to measure the expression levels of miR-183/-96/-182 and that of several retina-specific neuronal genes such as OTX2, NRL, PDC and DCT. The transfected cells also were immunocytochemically examined for retina-specific neuronal markers, including Rhodopsin, red opsin, CRX, Thy1, CD73, recoverin and PKCα, to determine the cellular fate of the transfected hRPE cells. Data showed that upon miR-183/-96/-182 overexpression in hRPE cultures, the expression of neuronal genes including OTX2, NRL, PDC and DCT was also upregulated. Moreover, miR-183 cluster-treated hRPE cells were immunoreactive for neuronal markers such as Rhodopsin, red opsin, CRX and Thy1. Both transcriptional and translational upregulation of neuronal genes in miR-183 cluster-treated hRPE cells suggests that in vitro overexpression of miR-183 cluster could trigger reprogramming of hRPE cells to retinal neuron fate.

A rare form of limb girdle muscular dystrophy (type 2E) seen in an Iranian family detected by autozygosity mapping.

Sarcoglycanopathies (SGPs) constitute a subgroup of autosomal recessive limb girdle muscular dystrophies (LGMDs) which are caused by mutations in sarcoglycan (SGs) genes. SG proteins form a core complex consisting of α, ß, γ and δ sarcoglycans which are encoded by SGCA, SGCB, SGCG and SGCD genes, respectively. Genetic defect, in any of these SG proteins, results in instability of the whole complex. This effect can be helpful in interpreting muscle biopsy results. Autozygosity mapping is a gene mapping approach which can be applied in large consanguineous families for tracking the defective gene in most autosomal recessive disorders. In the present study, we used autozygosity mapping, to find the gene responsible for muscular dystrophy. Proband was a 10-year-old boy referred to our center for ruling out DMD (Duchenne muscular dystrophy). According to the pedigree and clinical reports, we assessed him for SGPs. Haplotyping, using the four short tandem repeat (STR) markers for each of the SG genes, showed that the phenotype may segregate with SGCB gene; and observing two crossing overs which occurred within the gene suggested that the mutation might be in the first two exons of SGCB gene. Mutation analysis showed a 26 bp duplication (10 bp before the initiation codon till 13 bp after the ATG start codon). This will cause a frameshift in protein synthesis.

Prevalence of antibody to Hepatitis B core antigen and Hepatitis B virus DNA in HBsAg negative healthy blood donors.

BACKGROUND: Hepatitis B virus is one of the most important blood born viruses. Although the sensitivity of screening tests has been considerably increased, transmission may still occur due to window period or occult hepatitis B infections (OBIs). This study was aimed at evaluating the prevalence of the anti-HBc and identifying the HBV DNA in HBsAg negative blood donors. METHODS: The Blood samples from 2031 HBsAg-negative blood donors were divided into three aliquots and tested for anti-HBc, anti-HBs and HBV DNA. Serologic screening including anti-HBc and anti-HBs was performed. As a confirmatory test, all positive results for anti-HBc were retested with another kit. Two positive results were considered for anti-HBc positivity. All HBsAg negative selected donations were tested by PCR assay on pooled specimens (five samples per pool), plasma samples found to be HBsAg negative but anti-HBc positive were selected for a single-unit specimen Real-Time assay. RESULTS: The study population had a mean age of 33.25 ± 10.09 years were mainly composed of males (94.8 %). The seroprevalance rate was 4.9 % for Anti-HBc and 31.9 % for HBsAb. The majority (58.6 %) of Anti-HBc positive cases were regular blood donors with 42-49 years being the largest age group (41.4 %). Neither individual NAT nor pooled NAT test detected any HBV DNA. CONCLUSION: However, Screening of anti-HBc Ab is proposed as a method to identify previous contact with HBV, but there is controversy in literature data regarding the cost-benefit of exclusion of positive anti-HBc Ab in blood donors. Our data does not suggest HBc-Ab test as a screening tool in the study setting.

New procedure to design low radar cross section near perfect isotropic and homogeneous triangular carpet cloaks.

A new design procedure for near perfect triangular carpet cloaks, fabricated based on only isotropic homogeneous materials, is proposed. This procedure enables us to fabricate a cloak with simple metamaterials or even without employing metamaterials. The proposed procedure together with an invasive weed optimization algorithm is used to design carpet cloaks based on quasi-isotropic metamaterial structures, Teflon and AN-73. According to the simulation results, the proposed cloaks have good invisibility properties against radar, especially monostatic radar. The procedure is a new method to derive isotropic and homogeneous parameters from transformation optics formulas so we do not need to use complicated structures to fabricate the carpet cloaks.

Association of miR-146a rs2910164 and miR-149 rs2292832 Variants with Susceptibility to Type 2 Diabetes.

BACKGROUND: The deregulation of miRNAs has been implicated in the pathogenesis of type 2 diabetes (T2D). Single nucleotide polymorphisms (SNPs) located within the miRNA sequence could alter miRNA maturation and expression or change the binding affinity of miRNAs to their target mRNAs. In the present study we aimed to elucidate the possible association between the miR-146a rs2910164 and miR-149 rs2292832 variants with the susceptibility to T2D and its related metabolic traits in an Iranian population. METHODS: The study population consisted of 183 type 2 diabetic and 192 non-diabetic subjects. The genotyping of the variants was performed by a PCR-RFLP method. RESULTS: The frequency of the CC genotype of the miR-146a rs2910164 variant was significantly higher in diabetic patients than in controls (15.85% vs. 7.81%, p = 0.043). The results of binary logistic regression suggested that this genotype was significantly associated with T2D (OR of 2.43 (95% CI 1.17 - 5.02, p = 0.016). Moreover, subjects carrying the CC genotype had significantly higher values for diastolic blood pressure, triglycerides, total cholesterol, fasting blood glucose and HbAlc levels compared to individuals having the GG and GC genotypes. Our bioinformatic analyses also showed that the miR-146a sequence is conserved across primate taxa and substituting G to C causes the structural instability of pre-miR-146a by changing the minimum free energy. For the rs2292832 variant, no statistically significant difference was detected for allele or genotype frequencies between T2D and control groups. CONCLUSIONS: Our findings suggest that miR-146a rs2910164 polymorphism might be associated with T2D and its cardiovascular risk factors in an Iranian population.