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Abstract Background So far, high-density lipoprotein cholesterol (HDL-C) levels and mortality were shown to have a U-shaped relationship. Additionally, high HDL-C levels increase the risk of developing a variety of diseases. However, a paucity of data exists regarding the characteristics of people with high HDL-C levels. The aim of this study was to assess the demographics and characteristics of patients with high HDL-C levels and compare their features with normal and low HDL-C groups. Methods As a cross-sectional, matched case–control study, a total of 510 patients with type 2 diabetes (T2D) were enrolled in the study and categorized into three matched groups according to their HDL-C concentrations. The studied groups were matched by their age and gender. Restricted cubic spline (RCS) curves were designed to evaluate the relationship between height, blood pressure, triglyceride, and vitamin D concentrations with the probability of having high HDL-C levels. Furthermore, violin plots were conducted to illustrate the distribution of continuous variables within each group. Results This study showed that having high HDL-C (more than 70 mg/dL) compared to having low HDL-C (less than 40 mg/dL in men and 50 mg/dL in women) was significantly associated with height (OR 0.918, 95% CI 0.866–0.974), systolic blood pressure (SBP) (0.941, 0.910–0.972), vitamin D (0.970, 0.941–0.999), and triglyceride (0.992, 0.987–0.998) serum concentrations. Further analysis investigated that having high HDL-C levels compared to desired HDL-C levels (40 ≤ HDL-C levels

Abstract Background Coronavirus disease 2019 (COVID-19) has various sequelae, one of which might be hypertension. We aimed to evaluate COVID-19’s impact on blood pressure (BP) in non-hospitalized patients at one-year follow-up. Method A total of 7,950 consecutive COVID-19 patients regularly visiting our cardiology clinic were retrospectively screened. Patients’ electronic medical records including demographics, comorbidities, vital signs, treatments, and outcomes, were reviewed by two physicians. Individuals with at least one BP measurement in the three months preceding COVID-19 and one measurement in 12 months or more following recovery were included. BP levels before and after COVID-19 were compared using the paired t-test. Results 5,355 confirmed COVID-19 patients (mean age 55.51 ± 15.38 years) were included. Hypertension (56.9%) and diabetes mellitus (34%) were the predominant comorbidities, and 44.3% had prior major adverse cardiovascular events. Both systolic (126.90 ± 20.91 vs. 139.99 ± 23.94 mmHg, P

Abstract Surface modification of titanium and its alloys has been seriously considered by researchers to improve their biological behaviors, in the past few decades. In present research, hydroxyapatite (HA) based composite coatings with different concentrations of 0, 2, 4, and 6 wt% of silver (Ag) nanoparticles were electrophoretically deposited (EPD) on anodized and non-anodized Ti6Al4V, using a direct current at a voltage of 30 V for 10 min at room temperature. The specimens were then characterized by means of X-ray diffraction (XRD) analysis, Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS). The cell adhesion images and cell viability results showed that HA-Ag composite coatings significantly promoted the biocompatibility of samples compared with the non-anodized and anodized Ti6Al4V. The viabilities of Mg-63 cells on HA-4%Ag coating and bi-layer coating (HA-4%Ag on anodized specimen) were approximately 91% and they were considered as the best coatings in term of biocompatibility. On the other hand, the antibacterial assessments demonstrated that HA-6%Ag coating had the best antibacterial performance compared with other samples. Furthermore, Tafel polarization curves indicated that corrosion resistance of the bi-layer coating was higher than those of the other specimens. The polarization resistance of this coating was about 7 times more than that of theTi6Al4V alloy. Graphical Abstract

The aberrant subclavian artery is an uncommon congenital anomaly in the aortic arch, which may have a variety of presentations, including dysphagia, dyspnea, and chest pain, depending on the anatomical site of the aberrant vessel. Treatment is individualized, and surgical management is only considered in symptomatic patients. Dysphagia is one of the most important symptoms for which clinicians should consider surgery. Here, we present an interesting case of a 49-year-old woman who first came with the presentation of acute coronary syndrome and underwent coronary angiography, which showed no sign of significant lesions but revealed a probable abnormal left subclavian artery and right aortic arch. The patient refused further evaluation at that time; however, she came back after three years with progressive chest pain and dysphagia as a new complaint. After a step-by-step work-up for the patient's dysphagia, including barium swallow and upper endoscopy, chest CT angiography was performed that demonstrated a left aberrant subclavian artery as the potential cause of her complaints. After the diagnosis became clear, surgical ligation of the aberrant left subclavian artery and release of the vascular ring around the esophagus were done for the patient, as well as anastomosis of the left carotid artery to the left subclavian artery by saphenous vein graft interposition.

This investigation aims to study the effect of laser cladding parameters on the microstructure of Stellite 6 on the X19CrMoNbVN11-1 stainless-steel substrate. First, Stellite 6 powder was coated on the X19CrMoNbVN11-1 substrate using the laser cladding method. The effect of laser cladding parameters (i.e., laser power, scanning speed, and powder feed rate) was studied on the microstructure of deposits. The secondary dendritic arm spacing was assessed, and the structural defects were studied (e.g., lack of bonding, porosity, and crack). The results revealed that the microstructure has changed from coating/substrate interface to coating surface, from plate-cellular to columnar and equiaxed dendrites. Also, an increase in the laser power increased the cellular structure in the coating/substrate interface and equiaxed dendrites in the coating surface. The cooling rate (G × R) increased by increasing the scanning and powder injection rates. The microstructure of the Stellite 6 was composed of cobalt solid-solution γFCC.

The aim is to Investigate the effect of social responsibility performance on the relationship between tax planning and company value. Tax planning ability is an important influencing factor in determining the value of companies from the point of view of social responsibility. The Data belonging to 88 companies between the years 2016 and 2021 were selected from between the companies admitted to the Tehran Stock Exchange and social responsibility as a moderating variable, the independent variable of tax planning and the dependent variable of company value were used, which were investigated in separate regression models. The test of the first and second hypotheses shows that tax planning has a positive and significant relationship with company value, and the relationship between social responsibility and the relationship between tax planning and company value is positive and significant. The results show that with the improvement of tax planning, the value of companies improves and tax planning increases the value of the company. Increasing the social responsibility of the company increases the positive impact of tax planning and the value of the company. Research that examines the relationship between social responsibility, tax planning, and company value at the same time has not been done. By conducting this research, useful supplementary information has been provided for the field of investment, judgment decision-making, and taxation

TiB2+TiB coatings were formed on Ti–6Al–4V through a molten-salt diffusional process at temperatures of 850 °C and 900 °C for 16 h. The thickness of the TiB layer increased by about two times at the higher process temperature, while the thickness of the TiB2 layer remained constant. Tribocorrosion rate of Ti–6Al–4V and the coated samples was evaluated in a reciprocating sliding under a normal load of 15 N in a phosphate buffer saline (PBS) solution for 3600–36000 cycles against an alumina ball. The results showed that the tribocorrosion rate of the borided samples decreased up to 56 times compared with Ti–6Al–4V after 36000 cycles. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) studies showed the presence of oxide-rich patches on the wear surface of Ti–6Al–4V with a thickness of up to 1 μm. TEM and atomic force microscopy (AFM) images also revealed the presence of a tribofilm with a thickness of up to 200 nm on the surface of the boride coating. In addition, X-ray photoelectron spectroscopy (XPS) analysis confirmed the tribofilm formed on the wear surface of coated samples contained B2O3/H3BO3 compound, resulting in a more stable fluctuation in coefficient of friction and open circuit potential during sliding. The SEM images of the alumina wear surface showed cracks and titanium transfer layers in contact with the borided layers and Ti–6Al–4V, respectively.

The purpose of this study was the evaluate use of bio-fertilizers to adjustment water shortage stress and improved smooth vetch (Vicia dasycarpa L.) yield under water deficit stress conditions. Thus, A 2-year experiment were performed in an agrisilviculture system of plum orchard in 2016 and 2017. In this study, the single, double and triple combined of Arbuscular mycorrhizal fungi- Rhizophagus intraradices (AMF), Azotobacter chroococcum (Az) and Thiobacillus spp. (Th) on smooth vetch plants were evaluated under rain-fed and supplemental irrigation. The results indicated that irrigated plants had more Fe and Zn nutrients than rain-fed plants. Combined use of AMF + A. chroococcum more improved the forage dry matter digestibility (DMD), total digestible nutrient (TDN), net energy for lactation (NEL), dry matter intake (DMI) and relative feed value (RFV) than plants with single inoculation. In irrigated plants, double and triple combination of AMF with A. chroococcum and/or Thiobacillus spp. improved chlorophyll-a, chlorophyll-b, total chlorophyll, RWC, TSS, AsA, and GSH while lowering proline and MDA. Rain-fed condition reduced grain yield. In conclusion, synthesis non-enzymatic antioxidant because of the combined use of bio-fertilizers (AMF, Az and Th) can reduce ROS damage and improve water deficit resistance and yield in smooth vetch rain-fed plants.

Roadside units are crucial elements of intelligent transportation systems that provide vehicle–vehicle and vehicle–equipment information communication. Due to the high cost of installation, the deployment of roadside units is the most critical. Aim of this study is developing a model to optimize of roadside units placement to achieve maximum coverage. A multi–objective mathematical model presented, based on the three main parameters. These parameters are traffic volume, incident rate and adjacency to important centers, which determine for alternative points. The maximum coverage problem is NP–hard. Consequently, conventional mathematical methods are not accurate for large scale problem. A meta–heuristic method based on the greedy algorithm was developed which conciders marking points as definitive–select or non–selectable. Result of the model were evaluated through testing of three scenarios, 200, 500 and 1000 meters coverage in District 5 of Tehran by using MATLAB and the best one, 1000 meters was chosen with 71% coverage. Observations showed the effect of various parameters such as equipment coverage radius, number of equipment and budget on the results of distribution. This algorithm makes it possible to solve the problem on a large scale by using the geolocation of the candidate points.

Abstract Background Besides the lungs, coronavirus disease 2019 (COVID-19) can affect the cardiovascular, digestive, urinary, hepatic, and central nervous systems. Other than its short-term effects, COVID-19 may also cause long-term complications. In this study, we assessed long-term COVID-19 cardiovascular symptoms among patients in a cardiovascular clinic. Method A retrospective cohort was conducted between October 2020 to May 2021 on patients at an outpatient cardiovascular clinic in Shiraz, Iran. Patients with a history of COVID-19 at least one year before their referral were included. Baseline information was extracted from the clinic’s database. Data were collected regarding symptoms like dyspnea, chest pain, fatigue, and palpitations after a year of COVID-19. We also noted any major adverse cardiac events (MACE). Results Most common symptoms after a year of COVID-19 were exertional dyspnea (51.2%), dyspnea at rest (41.6%), fatigue (39%), and chest pain (27.1%). The symptoms were more prevalent in hospitalized patients than in non-hospitalized patients. The prevalence of MACE was about 6.1% during the 12-month follow-up, with this rate being higher in those with a history of hospitalization or comorbid diseases. Conclusion The prevalence of cardiovascular symptoms was fairly high in patients at our clinic a year after COVID-19, and the most common symptom was dyspnea. Hospitalized patients had more MACE. (Clinicaltrial.gov number: NCT05715879)(04/02/2023).

PurposeTo compare local ganglion cell-inner plexiform layer (GCIPL) thickness measurements between 2 OCT devices and to explore factors that may influence the difference in measurements.DesignCross-sectional study.ParticipantsSixty-nine glaucoma eyes (63 patients) with evidence of central damage or mean deviation (MD) of -6.0 dB or worse on a 24-2 visual field (VF).MethodsCirrus and Spectralis OCT macular volume scans were exported, data from the central 20° of both OCT devices were centered and aligned, and 50 × 50 arrays of 0.4° × 0.4° superpixels were created. We estimated nonparametric (Spearman's) correlations and used Bland-Altman plots to compare GCIPL thickness measurements between the two OCTs at the superpixel level. Factors that may have influenced the differences between thickness measurements between the two devices were explored with linear mixed models.Main outcome measuresPooled and individual-eye Spearman's correlation and agreement between thickness measurements from the two devices.ResultsThe median 24-2 VF MD was -6.8 dB (interquartile range [IQR], -4.9 to -12.3 dB). The overall pooled Spearman's correlation between the two devices for all superpixels and eyes was 0.97 (P < 0.001). The median within-eye correlation coefficient was 0.72 (IQR, 0.59-0.79). Bland-Altman plots demonstrated a systematic bias in most individual eyes, with Spectralis GCIPL measurements becoming larger than Cirrus measurements with increasing superpixel thickness. The average superpixel thickness and distance to the fovea influenced the thickness difference between the two devices in multivariate models (P < 0.001).ConclusionsLocal macular thickness measurements from the Spectralis and Cirrus devices are highly correlated, but not interchangeable. Differences in thickness measurements between the two devices are influenced by the location of superpixels and their thickness.

This study investigated the effect of organic fertilizers on vegetative growth and the physiological and antioxidant activity characteristics of thyme plants grown under stress. A factorial experiment was conducted according to randomized complete block design with 12 combinations and 3 replications in the 2018 growing season. The experiment factors were the implementation of organic fertilizers at 4 levels (vermicompost, manure compost, animal manure, and control) and irrigation regime at 3 levels (Irr1, Irr2, and Irr3, respectively, irrigation after 60, 90, and 120 mm evaporation from A pan). The results showed that With delayed irrigation, the chlorophyll a and b contents, total chlorophyll, and carotenoid decreased, while the application of low water stress enhanced the amount of oil and the oil yield with the respective highest values of 2.61% and 3.68 g/m under mild stress conditions. Nonetheless, higher values for the aforementioned properties were noted with the application of vermicompost. Water deficit decreased nutrient uptake (K, P, and N) and relative water content, biological yield, and seed yield of thyme, indicating that thyme was sensitive to drought, and organic fertilizers application improved nutrient uptake (K, P, and N) and relative water content, biological yield and seed yield of the plant within irrigation levels. The activities of catalase, superoxide dismutase and ascorbate peroxidase were reduced under organic fertilizers such as vermicompost and manure compost as compared with control under drought stress. The plants of thyme showed a good response to organic fertilizers under water deficit circumstances, with vermicompost being the most effective.

Abstract Long noncoding RNAs are characterized as noncoding transcripts longer than 200 nucleotides in response to a variety of functions within the cells. They are involved in almost all cellular mechanisms so as epigenetics. Given that epigenetics is an important phenomenon, which participates in the biology of complex diseases, many valuable studies have been performed to demonstrate the control status of lncRNAs and epigenetics. DNA methylation and histone modifications as epigenetic mechanisms can regulate the expression of lncRNAs by affecting their coding genes. Reciprocally, the three-dimensional structure of lncRNAs could mechanistically control the activity of epigenetic-related enzymes. Dysregulation in the mutual interaction between epigenetics and lncRNAs is one of the hallmarks of cancer. These mechanisms are either directly or indirectly involved in various cancer properties such as proliferation, apoptosis, invasion, and metastasis. For instance, lncRNA HOTAIR plays a role in regulating the expression of many genes by interacting with epigenetic factors such as DNA methyltransferases and EZH2, and thus plays a role in the initiation and progression of various cancers. Conversely, the expression of this lncRNA is also controlled by epigenetic factors. Therefore, focusing on this reciprocated interaction can apply to cancer management and the identification of prognostic, diagnostic, and druggable targets. In the current review, we discuss the reciprocal relationship between lncRNAs and epigenetic mechanisms to promote or prevent cancer progression and find new potent biomarkers and targets for cancer diagnosis and therapy.

Surface melting and alloying of Copper-Nickel (Cupronickel) alloy by preplacing aluminum powder and using tungsten inert gas process (TIG) in shielded atmosphere of argon gas were investigated. Surface melting resulted in the formation of a fairly porous dendritic microstructure. Surface alloying with aluminum resulted in the formation of Al 2Cu and Al 4Cu 9 intermetallic compounds along with Cu-rich matrix and unstable martensitic structure. Surface melting reduced the hardness from 140 HV 0.1 (substrate) to 70 HV 0.1, mainly due to the loss of cold work effect of the initial substrate. On the other hand, surface alloyed zone showed a hardness of 300 HV 0.1, mainly due to the formation of intermetallic compound. Tafel polarization results indicated improvement in corrosion resistance of cupronickel alloy after surface melting and alloying.

Background: High-risk sexual activities are a major social concern. Thus, the present study was conducted with the aim to assess the awareness of male medical students regarding high-risk sexual behaviors. Methods: This cross-sectional study was performed on 86 male students who had been studying at Shahid Beheshti University in 2018-19. We used a researcher-made checklist. The demographic information of students and their knowledge of sexually transmitted diseases‎ (STDs), STD treatments and prevention methods, and human papillomavirus (HPV) were assessed. They were also asked about their Gardasil and Hepatitis B vaccination stage. The collected data were analyzed in SPSS software. Results: We found that 58.1% of students were sexually active. Moreover, 37.25% of them reported receiving sex education from their parents or at schools. Although 93% of students knew at least one contraceptive device, 20.9% of them had experienced high-risk sexual relationships, which is significantly high. However, none of the students had acquired an STD. In addition, 89.0% and 75.0% of students had knowledge of STDs and their prevention ‎methods, respectively. 68.19% of students had knowledge about HPV. Students were well informed about vaccines against STDs; however, only 18.6% of them were vaccinated. Conclusion: Overall, students were well informed. A considerable number of them had experienced high-risk sexual activities. It seems that our high rates are due to the fact that we only assessed medical students. We recommend that authorities in the education system reconsider their attitude toward this issue and include sex education in the medical education curriculum ‎in order to prevent these infections.

Abstract Mg-based biomaterials are commonly used as biodegradable orthopedic implants (e.g., bone regeneration applications). However, achieving high biocompatibility and corrosion resistance has remained a challenge to be tackled. In this work, to investigate various fabricated coatings (with and without pre- anodizing), five categories of samples are considered: (a) bare Mg alloy (Mg), (b) Anodized Mg alloy (Mg-A), (c) CS-coated Mg alloy (Mg-C), (d) CS-coated anodized Mg alloy (Mg-AC), and (e) CS-CNT-coated anodized Mg alloy (Mg-ACC). These samples were characterized by using Field Emission Scanning Electron Microscopes (FE-SEM), Energy Dispersive Spectroscopy (EDS), Fourier Transform Infrared Spectroscopy (FT-IR), and Raman Spectroscopy. The adhesion within the coated samples was compared. Then, the effects of the coatings were evaluated by comparing wettability, corrosion behavior, and biocompatibility for bare and coated samples. The adhesion test showed that the coatings exhibited higher adhesion for Mg-AC and Mg-ACC compared to Mg-C. Desired wettability was achieved as the contact angles of coated samples were in the range of 55°– 65°. Electrochemical impedance and polarization as well as immersion tests showed higher corrosion resistance for coated samples. The composite coated sample showed improved cell adhesion since the osteoblast cells covered almost the entire surface of the sample. Moreover, osteoblast cell viability for the sample was around 40% higher than that of the bare sample. Graphical abstract

The purpose of this study was to Survey of the success key factors application in the implementation of knowledge management in Water and Power Organization of Khuzestan.This research is applied in terms of purpose and a quantitative by using a descriptive survey method. The data collection tool is a questionnaire whose reliability was calculated by Cronbach's alpha test of 0.87. In the present study, one-sample test, Kolmogorov-Smirnov test has been used. The data of this study were analyzed using SPSS software version 26. The results indicate that the mean of organizational structure (2.89) in knowledge management implemented in the Khuzestan Water and Power Organization is lower than average. Regarding the status of organizational culture (3.20) in knowledge management implemented in Khuzestan Water and power Organization, the results showed that the mean acquisition is higher than average. The results show that the mean status of information technology (3.23) in knowledge management implemented in Khuzestan Water and power Organization is higher than average While the results indicate that the mean status of human resources (2.75) in knowledge management implemented in the Khuzestan Water and power Organization is lower than average. Finally, the results indicate that the leadership status (3.75) in the knowledge management implemented in the Khuzestan Water and power Organization is higher than average. Among the success key factors for the implemented knowledge management; The organizational structure and human resources are not at the desired level and it is necessary to provide the ground for improving the status of these factors by planning in this regard.

This research has focused on isolating and identifying different thermoacidophilic bacteria from a Sarcheshmeh low-grade copper ore and evaluating their ability of copper bioleaching from the mineral tailing. After the isolation of the bacteria, molecular identification was carried out based on the 16S rRNA gene sequences and drawing the phylogenetic tree. Then, the effect of the pH, pulp density, and composition of the media on the copper bioleaching was determined using the identified bacteria. The isolated strain (Strain SCM1) belonged to Delftia acidovorans with a 95.73% of identity. The optimal condition for the copper bioleaching was reported in a medium consisting of sulfur (10 g/L), glucose (10 g/L), yeast extract (2 g/L), and mineral tailing (5% wt/vol) at the pH of 2.00 at 50°C. Under this condition, the highest amount of copper (83%) was bioleached. It proves that the lately isolated strain can be effectively employed in the copper bioleaching process.

In this work, dry tribological behaviors of commercial pure (Cp) titanium and diffusion coated titanium were studied and compared. Wear tests were performed by a pin on disk tribometer using 52100 steel pins, under various loads of 10, 20, and 40 N. Worn surfaces were examined by scanning electron microscope, equipped with EDS analyzer. The wear rates of the coated materials were lower than those of the Cp titanium. This is mainly attributed to the higher hardness of the NiTi layer (about 280 HV) which is 1.5 times higher than that of the untreated titanium (about 180 HV). In addition, the SEM analysis of the worn surfaces revealed that the formation of tribological layer on the surface of the diffusion treated material effectively lowered the wear rate. The results also demonstrated a lower coefficient of friction in the treated specimens compared to those of the Cp materials.

In this research, CoFeNi thick films were prepared through the electrodeposition process from a natural pH bath containing the complex agent of sodium citrate. By increasing applied current density, there is a transition from BCC (Fe) phase to BCC (Fe) + FCC (Co) phases and then to FCC (Co) phase. The XRD pattern showed a nanocrystalline structure for the CoFeNi thick films which was further confirmed by the TEM images. The magnetic properties of the synthesized magnetic films exhibit a noticeable decrease in the coercivity by decreasing the crystallite size which is consistent with the “D6” law. The resistivity of the CoFeNi thick films increased by decreasing the grain size which is due to the scattering of the charge carriers. The increase in the applied current density results in the gradual substitution of the iron atoms in CoFeNi films by nickel atoms leading to a reduction in saturation magnetization.

Abstract Background and Objective: Disposal of fishery wastes is one of the environmental challenges. Converting wastes into valuable products is an economical solution to solve this environmental problem. One of the wastes of fishery products is shrimp shell waste, which contains large quantities of chitin. Chitin and its derivative, chitosan, include several uses in various industries, especially the food industry. The aim of the present study was to extract chitin from shrimp shell wastes using co-fermentation with mixed microbial cultures. Chitosan production by deacetylation of chitin using various concentrations of NaOH was another aim of this study. Material and Methods: Batch fermentation was carried out to extract chitin from the shrimp shell using mixed cultures of two microorganisms, Lactiplantibacillus plantarum PTCC 1745 and Bacillus subtilis PTCC 1720. The Logistic model was used to assess the microbial growth rate. To prepare chitosan from chitin, deacetylation was carried out using NaOH solution. Morphological structures of the chitin and chitosan were studied using scanning electron microscopy. Functional groups of the synthesized chitin and chitosan were assessed using Fourier transform infrared spectroscopy. Results and Conclusion: High levels of demineralization and deproteinization were achieved using co-fermentation with the mixed microbial populations at 60 g.l-1 of glucose concentration. Chitin was produced with high purity and the protein and ash contents included 1.43 and 1.26%, respectively. Data predicted by the Logistic model were fairly matched the experimental data. A maximum cell growth rate of 0.065 (h-1) was achieved at 60 g.l-1 of initial glucose concentration at 35 °C. The optimal value of deacetylation (88.2%) was achieved using 50% NaOH solution at 100 °C. The results showed that the use of mixed culture of acid-producing and proteolytic microorganisms is highly effective for extracting chitin from shrimp shell waste. Conflict of interest: The authors declare no conflict of interest.

Abstract Background Gene silence via methylation of the CpG islands is cancer's most common epigenetic modification. Given the highly significant role of NIS in thyroid cancer (TC) differentiation, this cross-sectional study aimed to investigate the DNA methylation pattern in seven CpG islands (CpG1-7 including +846, +918, +929, +947, +953, +955, and +963, respectively) of the NIS promoter in patients diagnosed with papillary (PTC), follicular (FTC), and multinodular goiter (MNG). Additionally, a systematic review of the literature was conducted to compare our results with studies concerning methylation of the NIS gene promoter. Methods Thyroid specimens from 64 patients met the eligibility criteria, consisting of 28 PTC, 9 FTC, and 27 benign MNG cases. The mRNA of NIS was tested by qRT-PCR. The bisulfite sequencing PCR (BSP) technique was performed to evaluate the promoter methylation pattern of the NIS gene. Sequencing results were received in chromatograph, FASTA, SEQ, and pdf formats and were analyzed using Chromas. The methylation percentage at each position and for each sample was calculated by mC/(mC+C) formula for all examined CpGs; following that, the methylation percentage was also calculated at each CpG site. Besides, a literature search was conducted without restricting publication dates. Nine studies met the eligibility criteria after removing duplicates, unrelated articles, and reviews. Results NIS mRNA levels decreased in tumoral tissues of PTC (P = 0.04) and FTC (P = 0.03) patients compared to their matched non-tumoral ones. The methylation of NIS promoter was not common in PTC samples, but it was frequent in FTC (P