Assessment of air quality using AERMOD modeling: a case study in the Middle East.

Emissions of greenhouse gases from industrial facilities, such as refineries, are one of the most significant environmental problems in many countries. This study aimed to assess the present status of emission sources near a gas refinery region, and the contribution of sources to air pollution was estimated by monitoring CO for a year at a fixed station. This descriptive-analytical study was conducted between January and December 2020. A simulation of CO gas distribution and pollutant concentration prediction was carried out. The results show that the maximum concentration of CO in the 1-h period was 2260 µg/m3, which corresponds to the peak concentration in spring, and in the 8-h period, it was 573 µg/m3, which corresponds to the peak concentration in winter. The studied area's maximum pollutant concentration was also compared to national and international standards for clean air. In all four seasons, the maximum simulated CO concentrations were lower than the Iranian and EPA standards for clean air. Maximum concentrations have occurred in the southern slopes of the study area's heights, and, due to the appropriate wind speed, maximum concentrations in the northeastern mountain peaks occurred at a more considerable distance due to the high altitude of the mountains and the lack of suitable conditions for pollutant escape. Furthermore, because of the height of smokestacks and flares from the ground and the effect of wind on the release height, the concentration of pollutants at the foot of the stacks is low and decreases gradually over a certain distance. Finally, the distribution and deposition of pollutants in the pathway of the smoke were influenced by the type of topography.

Effective Connectivity Evaluation of Resting-State Brain Networks in Alzheimer's Disease, Amnestic Mild Cognitive Impairment, and Normal Aging: An Exploratory Study.

(1) Background: Alzheimer's disease (AD) is a neurodegenerative disease with a high prevalence. Despite the cognitive tests to diagnose AD, there are pitfalls in early diagnosis. Brain deposition of pathological markers of AD can affect the direction and intensity of the signaling. The study of effective connectivity allows the evaluation of intensity flow and signaling pathways in functional regions, even in the early stage, known as amnestic mild cognitive impairment (aMCI). (2) Methods: 16 aMCI, 13 AD, and 14 normal subjects were scanned using resting-state fMRI and T1-weighted protocols. After data pre-processing, the signal of the predefined nodes was extracted, and spectral dynamic causal modeling analysis (spDCM) was constructed. Afterward, the mean and standard deviation of the Jacobin matrix of each subject describing effective connectivity was calculated and compared. (3) Results: The maps of effective connectivity in the brain networks of the three groups were different, and the direction and strength of the causal effect with the progression of the disease showed substantial changes. (4) Conclusions: Impaired information flow in the resting-state networks of the aMCI and AD groups was found versus normal groups. Effective connectivity can serve as a potential marker of Alzheimer's pathophysiology, even in the early stages of the disease.

Relationship between serum nitric oxide of patients with thyroid disorders and metabolic syndrome indices and nitrate concentration of water.

This case-control study aimed to assess the effect of drinking water nitrate on serum nitric oxide concentration and the risk of metabolic syndrome (MetS) in the population in the Middle East. The study included 50 control and 50 thyroid disorder cases who were referred to two medical centers in 2021. In this study, serum nitric oxide concentration, drinking water nitrate, and metabolic syndrome components were measured in the two groups. The results showed there was a statistically significant difference between serum NO in the case and control groups (p-value < 0.001). There was a positive correlation between the concentration of nitrate in drinking water and serum nitric oxide in the case and control groups; however, this relationship was not significant statistically. A statistically significant difference was found between serum nitric oxide and systolic blood pressure in the cases (p-value < 0.05), but there was no significant difference between MetS and nitric oxide. Therefore, we concluded that the relationship between nitric oxide and nitrate in consuming water should be determined in thyroid patients. In addition to their water consumption, it is better to study the nitrate of foods, especially vegetables.

Quantitative Assessment of Resting-State Functional Connectivity MRI to Differentiate Amnestic Mild Cognitive Impairment, Late-Onset Alzheimer's Disease From Normal Subjects.

BACKGROUND: Alzheimer disease (AD) is a neurological disorder with brain network dysfunction. Investigation of the brain network functional connectivity (FC) alterations using resting-state functional MRI (rs-fMRI) can provide valuable information about the brain network pattern in early AD diagnosis. PURPOSE: To quantitatively assess FC patterns of resting-state brain networks and graph theory metrics (GTMs) to identify potential features for differentiation of amnestic mild cognitive impairment (aMCI) and late-onset AD from normal. STUDY TYPE: Prospective. SUBJECTS: A total of 14 normal, 16 aMCI, and 13 late-onset AD. FIELD STRENGTH/SEQUENCE: A 3.0 T; rs-fMRI: single-shot 2D-EPI and T1-weighted structure: MPRAGE. ASSESSMENT: By applying bivariate correlation coefficient and Fisher transformation on the time series of predefined ROIs' pairs, correlation coefficient matrixes and ROI-to-ROI connectivity (RRC) were extracted. By thresholding the RRC matrix (with a threshold of 0.15), a graph adjacency matrix was created to compute GTMs. STATISTICAL TESTS: Region of interest (ROI)-based analysis: parametric multivariable statistical analysis (PMSA) with a false discovery rate using (FDR)-corrected P < 0.05 cluster-level threshold together with posthoc uncorrected P < 0.05 connection-level threshold. Graph-theory analysis (GTA): P-FDR-corrected < 0.05. One-way ANOVA and Chi-square tests were used to compare clinical characteristics. RESULTS: PMSA differentiated AD from normal, with a significant decrease in FC of default mode, salience, dorsal attention, frontoparietal, language, visual, and cerebellar networks. Furthermore, significant increase in overall FC of visual and language networks was observed in aMCI compared to normal. GTA revealed a significant decrease in global-efficiency (28.05 < 45), local-efficiency (22.98 < 24.05), and betweenness-centrality (14.60 < 17.39) for AD against normal. Moreover, a significant increase in local-efficiency (33.46 > 24.05) and clustering-coefficient (25 > 20.18) were found in aMCI compared to normal. DATA CONCLUSION: This study demonstrated resting-state FC potential as an indicator to differentiate AD, aMCI, and normal. GTA revealed brain integration and breakdown by providing concise and comprehensible statistics. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY: Stage 2.

Brain Cortical Activation during Imagining of the Wrist Movement Using Functional Near-Infrared Spectroscopy (fNIRS).

BACKGROUND: fNIRS is a useful tool designed to record the changes in the density of blood's oxygenated hemoglobin (oxyHb) and deoxygenated hemoglobin (deoxyHb) molecules during brain activity. This method has made it possible to evaluate the hemodynamic changes of the brain during neuronal activity in a completely non-aggressive manner. OBJECTIVE: The present study has been designed to investigate and evaluate the brain cortex activities during imagining of the execution of wrist motor tasks by comparing fMRI and fNIRS imaging methods. MATERIAL AND METHODS: This novel observational Optical Imaging study aims to investigate the brain motor cortex activity during imagining of the right wrist motor tasks in vertical and horizontal directions. To perform the study, ten healthy young right-handed volunteers were asked to think about right-hand movements in different directions according to the designed movement patterns. The required data were collected in two wavelengths, including 845 and 763 nanometers using a 48 channeled fNIRS machine. RESULTS: Analysis of the obtained data showed the brain activity patterns during imagining of the execution of a movement are formed in various points of the motor cortex in terms of location. Moreover, depending on the direction of the movement, activity plans have distinguishable patterns. The results showed contralateral M1 was mainly activated during imagining of the motor cortex (p<0.05). CONCLUSION: The results of our study showed that in brain imaging, it is possible to distinguish between patterns of activities during wrist motion in different directions using the recorded signals obtained through near-infrared Spectroscopy. The findings of this study can be useful in further studies related to movement control and BCI.

Clinical and Laboratory Characteristics of a Large Iranian Kindred Afflicted with Von Hippel Lindau Disease.

BACKGROUND: Von Hippel Lindau (VHL) disease is a hereditary disorder characterized by the development of benign or malignant tumors in the brain, spinal cord, eyes, adrenal medulla, kidney, pancreas, and many other organs. Advances in molecular diagnosis have led to the identification of the affected members of families at earlier stages. We present the clinical, laboratory, and genetic characteristics of five generations of a large Iranian kindred with VHL. METHODS: The proband, a 52-year-old Iranian man, was recognized with VHL. All family members underwent clinical, laboratory, imaging, and genetic evaluation. Medical files and histopathology reports of patients who had been operated on before were also reviewed. Diagnosis of the disease was based on clinical findings, positive family history of VHL, and development of a central nervous system or retinal hemangioblastoma or pheochromocytoma. RESULTS: Based on diagnostic criteria, our initial evaluations revealed that 10 members of the family had already been affected by the disease. Among them, nine had pheochromocytoma, and one had retinal hemangioblastoma. There was no case of kidney tumors among the kindred. CONCLUSIONS: Study results show the high penetrance of the disease and focus on the large burden imposed by the disease on the health and quality of life of patients afflicted with the disease, emphasizing the importance of surveillance from early childhood for detection and management of the disease as early as possible.

Evaluation of contrast agent dose and diffusion coefficient measurement on vessel size index estimation.

OBJECTIVES: The goal of this study is to examine the effect of contrast agent (CA) dose and diffusion coefficient on the estimation of vessel size index (VSI). MATERIALS AND METHODS: Three groups of four participants were enrolled in this study and two different experiments were performed. Different dose of CA, namely 0.1 mmol/kg and 0.05 mmol/kg were assessed in two groups of normal subjects. Diffusion coefficient effect was assessed in the third group with high-grade glioma. Imaging included gradient echo and spin-echo DSC and DTI on a 3-T MR Scanner. RESULTS: VSI estimation using half of standard dose of CA showed higher values compared to the application of standard, with a ratio of 2 for the WM and 1.5 for the GM. VSI estimates for tumor tissues (22 µm) were considerably higher compared to contra-lateral Normal-Appearing WM (NAWM, 4 µm, P < 0.01) and Normal-Appearing GM (NAGM, 8 µm, P < 0.04). DISCUSSION: Application of standard dose for CA injection and also taking into account the effect of diffusion coefficient can lead to a better correlation of VSI with previous theoretically predicted values and improvement of individual diagnostics in tumor evaluations.

Evaluation of iron deposition in brain basal ganglia of patients with Parkinson's disease using quantitative susceptibility mapping.

AIM OF THE STUDY: Parkinson's disease is associated with iron deposition in the brain. The QSM (quantitative susceptibility mapping) is more sensitive than T2-weighted imaging, T2* and R2. Few studies have been used QSM to evaluate the iron in the basal ganglia of patients with Parkinson's disease. Our aim was to evaluate the iron deposition in the basal ganglia using QSM and determination of diagnostic value of this method and evaluation of the association between disease stage with QSM and age with QSM in all nuclei, separately. MATERIALS AND METHODS: Thirty patients were tested using Hoehn and Yahr test in three different stages. Fifteen healthy subjects were considered as control group. MRI sequences were performed using SIEMENS 3 T scanner.The Signal Processing in NMR software was used to process and analyze the images. The QSM in every of the basal ganglia was measured separately. RESULTS: There was a significant difference for QSM in the Subtania Nigera, Red Nucleus, Thalamic Nucleus and Globus Pallidus nucleus between two groups. The relationship between disease stage with QSM was significant in Subtania Nigera, Red Nucleus, and Globus Pallidus nucleus. The QSM values had a significant association with disease stage in all nuclei. The results showed that QSM has a higher accuracy in Subtania Nigera, Globus Pallidus, Red Nucleus and Thalamic Nucleus, respectively. CONCLUSIONS: Using QSM in Red Nucleus, Subtania Nigera, and Globus Pallidus nuclei can help diagnosis and staging the patients with Parkinson's disease. In future, studies with emphasis on the disease stage can be helpful in evaluation the different parts of these three nuclei.

Geographical inequality in cataract surgery among Iranians between 2006 and 2011.

BACKGROUND: Cataract surgery is a highly cost-effective intervention for sight restoration but inequalities exist in its use which health care systems should aim to reduce. AIMS: This study aimed to measure the level of inequality in cataract surgery use and the changes in inequality between 2006 and 2011 in the Islamic Republic of Iran. METHODS: A number of metrics, including ranges and indexes based on Lorenz curves (Gini, concentration and dissimilarity indexes), were used to measure the inequality in cataract surgery use among Iranians in 2006 and 2011. Cataract surgical numbers and socioeconomic data were obtained from a province-based survey and the national census database. RESULTS: Significant inter-provincial and inter-regional differences were found in cataract surgical proportions. South Khorasan province had the lowest cataract surgical rate in 2006 and 2011, while Tehran province had the highest rate in both years. Inequality in the distribution of cataract surgery services decreased between 2006 and 2011: the Gini, concentration and dissimilarity indexes decreased by 0.028, 0.03 and 0.037, respectively. However, cataract surgery delivery remained in favour of the better-off provinces. CONCLUSIONS: To reduce this inequality, policy-makers should improve financial and physical access to cataract surgery, especially in the relatively deprived provinces, and tackle physician-induced demand.

Economic Inequality in Presenting Vision in Shahroud, Iran: Two Decomposition Methods.

BACKGROUND: Visual acuity, like many other health-related problems, does not have an equal distribution in terms of socio-economic factors. We conducted this study to estimate and decompose economic inequality in presenting visual acuity using two methods and to compare their results in a population aged 40-64 years in Shahroud, Iran. METHODS: The data of 5188 participants in the first phase of the Shahroud Cohort Eye Study, performed in 2009, were used for this study. Our outcome variable was presenting vision acuity (PVA) that was measured using LogMAR (logarithm of the minimum angle of resolution). The living standard variable used for estimation of inequality was the economic status and was constructed by principal component analysis on home assets. Inequality indices were concentration index and the gap between low and high economic groups. We decomposed these indices by the concentration index and BlinderOaxaca decomposition approaches respectively and compared the results. RESULTS: The concentration index of PVA was -0.245 (95% CI: -0.278, -0.212). The PVA gap between groups with a high and low economic status was 0.0705 and was in favor of the high economic group. Education, economic status, and age were the most important contributors of inequality in both concentration index and Blinder-Oaxaca decomposition. Percent contribution of these three factors in the concentration index and Blinder-Oaxaca decomposition was 41.1% vs. 43.4%, 25.4% vs. 19.1% and 15.2% vs. 16.2%, respectively. Other factors including gender, marital status, employment status and diabetes had minor contributions. CONCLUSION: This study showed that individuals with poorer visual acuity were more concentrated among people with a lower economic status. The main contributors of this inequality were similar in concentration index and Blinder-Oaxaca decomposition. So, it can be concluded that setting appropriate interventions to promote the literacy and income level in people with low economic status, formulating policies to address economic problems in the elderly, and paying more attention to their vision problems can help to alleviate economic inequality in visual acuity.

The PERSIAN Cohort: Providing the Evidence Needed for Healthcare Reform.

In the past, communicable diseases caused the highest mortality in Iran. Improvements in socioeconomic status and living standards including access to safe drinking water, along with the inception of Health Houses in the 1980s, have changed disease patterns, decreasing the spread of and deaths from infectious and communicable diseases. The incidence and prevalence of non-communicable diseases (NCD), however, have now increased in Iran, accounting for nearly 80% of deaths and disabilities. Without interventions, NCD are predicted to impose a substantial human and economic burden in the next 2 decades. However, Iran's health system is not equipped with the necessary policies to combat this growth and must refocus and reform. Therefore, in the year 2013, the Ministry of Health and Medical Education funded a well-designed nationwide cohort study-Prospective Epidemiological Research Studies in IrAN (PERSIAN)-in order to assess the burden of NCD and investigate the risk factors associated with them in the different ethnicities and geographical areas of Iran. The PERSIAN Cohort, which aims to include 200000 participants, has 4 components: Adult (main), Birth, Youth and Elderly, which are being carried out in 22 different regions of Iran. Having an enormous dataset along with a biobank of blood, urine, hair and nail samples, the PERSIAN Cohort will serve as an important infrastructure for future implementation research and will provide the evidence needed for new healthcare policies in order to better control, manage and prevent NCD.

Drug Literacy in Iran: the Experience of Using "The Single Item Health Literacy Screening (SILS) Tool".

Drug and health literacy is a key determinant of health outcomes. There are several tools to assess drug and health literacy. The objective of this article is to determine drug literacy level and its relationships with other factors using a single item screening tool. A cross-sectional survey was conducted among 1104 people in Qazvin province, Iran. Based on the proportional-to-size method, participants over 15 years old with ability to read were recruited randomly from 6 counties in Qazvin province and were interviewed directly. To determine drug literacy relationship with other variables, Chi-Square and t-test were used. Also, logistic regression model was used to adjust the relationship between drug literacy and other relevant variables. Response rate in clusters was 100%. Findings showed that inadequate drug literacy in Qazvin province is 30.3% and it was in association with (1) age (p = .000), (2) marital status (p = .000), (3) educational attainment (p = .000), (4) home county (p = .000), (5) residing area (p = .000), (6) type of basic health insurance (p = .000), (7) complementary health insurance status (p = .000), and (8) family socioeconomic status (p = .000). After adjusting for these variables using logistic regression model, the association between (1), (3), (4), (5) and (8) with drug literacy level was confirmed. The analysis also showed that this method can also be used in other health care settings in Iran for drug and health literacy rapid assessment.

Microbial keratitis after INTACS implantation with loose suture.

PURPOSE: To report a case of rapidly progressive infectious keratitis after INTACS implantation for keratoconus. METHODS: A 32-year-old man presented with pain and decreased vision in the right eye of 2 days' duration. Right eye visual acuity was 20/800. He had undergone bilateral INTACS implantation 40 days prior for treatment of keratoconus. RESULTS: Slit-lamp examination revealed corneal ulceration and loose suture. The corneal ulcer progressed despite aggressive therapy, and the patient underwent penetrating keratoplasty 48 hours after admission. The culture from corneal scraping and corneal button was positive for Staphylococcus aureus. CONCLUSIONS: Infectious keratitis is a rare but devastating complication of INTACS implantation for treatment of keratoconus. Meticulous wound closure is necessary to reduce the risk of infection, especially in eyes with irregular corneal contour and variable corneal thickness.

Microkeratome-assisted posterior lamellar keratoplasty in pseudophakic and aphakic corneal edema.

PURPOSE: To evaluate the outcome of microkeratome-assisted posterior lamellar keratoplasty for replacing diseased endothelium in pseudophakic and aphakic corneal edema. METHODS: Microkeratome-assisted posterior lamellar keratoplasty was performed on 10 eyes with pseudophakic or aphakic corneal edema. A nasal hinged 130- to 250-microm-thick flap was created with an automated microkeratome. The underlying 7.0-mm trephined button of deep stroma and endothelium was substituted with the same size donor button prepared by removing a same-sized flap and trephination of the remaining donor bed. The donor lenticule was fixated without sutures in position; the retracted flap was repositioned and sutured to the peripheral recipient tissue. The viscoelastic content of the anterior chamber was replaced by air to hold the graft in position. RESULTS: All surgeries were uneventful except for one case of donor button posterior dislocation forming a secondary anterior chamber, which was corrected through donor button exchange 1 month postoperatively. All uncomplicated cases had stable refraction and corneal topography as early as 1 month after surgery, which was maintained in follow-up examinations. In two eyes, corneal astigmatism > 5.00 diopters was recorded. One case of prolonged re-epithelialization and two cases of epithelial interface ingrowth occurred. CONCLUSIONS: Microkeratome-assisted posterior lamellar keratoplasty is an alternative to conventional penetrating keratoplasty for patients with diseased corneal endothelium, significantly reducing the time of visual rehabilitation. Determination of the relative advantages of this technique over penetrating keratoplasty and other recent alternative endothelial graft procedures relies on controlled prospective studies.