Central Area Of Iran Research Articles

Enhancing geochemical background estimation using rock weathering

The chemical composition of stream sediments is heavily influenced by weathering processes occurring in upstream lithological units. Despite their importance, these processes are frequently ignored in the examination of stream sediment geochemical data when identifying mineralized zones. Instead, existing geochemical background estimation procedures rely on the area size of upstream rocks as an indicator of their contribution to elemental concentrations of sediments. To address this limitation, a stream sediment geochemical survey was conducted in a pilot area in central Iran, and the physico-mechanical properties of upstream rock types, including elastic velocities, porosity, and Schmidt hammer rebound values, were evaluated. A new weathering index, “Wij,” was developed, utilizing proxies of rock weathering to estimate the geochemical background attributed to lithology at sediment sampling sites. The regression model was constructed by combining weathering proxies (Wij) with other independent variables, including the presence or absence of rocks in catchments, area size (Xij), and the weathering-corrected contributing factor (XijWij). The results suggested the significant capability of weathering proxies in explaining the geochemical variability of major elements such as Al, K, Fe, Ca, and Na. However, the regression model using weathering-corrected contributing factors delivered better overall accuracy than other independent variables. Nevertheless, our results also identified some limitations of the application of regression model in stream sediment data analysis.

THE ARABIA – EURASIA COLLISION ZONE IN IRAN: TECTONOSTRATIGRAPHIC AND STRUCTURAL SYNTHESIS

The Arabia – Eurasia collision zone in the central part of the Alpine – Himalayan orogenic system has had a complex deformation history since the Palaeozoic. In Iran, the collision zone consists of the Alborz‐Talesh, Kopeh Dagh and Zagros foldbelts and the intervening Central Iran area. In this review paper, we summarize the structural architecture and tectonostratigraphic characteristics of these domains and attempt to correlate regional deformation events between them. The results show that six regional‐scale deformation phases can be recognized and correlated in Iran over a time interval extending from the Late Palaeozoic to the Late Cenozoic.Late Palaeozoic rifting in northern Gondwana and subsequent oceanic spreading resulted in the separation of the Central and North Iran blocks from the Arabian Platform. These blocks later converged and collided with the southern margin of Eurasia due to the subduction of the intervening PalaeoTethys lithosphere (“Cimmerian orogeny”: Late Triassic). The convergent setting resulted in the initial development of the Alborz‐Talesh foldbelt in present‐day northern Iran, while extensional basins developed in the forebulge area in Central Iran. Continuing northward subduction of NeoTethyan oceanic lithosphere at the southern Eurasia margin produced Early Cretaceous back‐arc extension and associated volcanism in Central Iran and the Alborz‐Talesh area to the north. A phase of compressional deformation in the Late Cretaceous was related to the collision of a series of microcontinents derived from Northern Gondwana, including the Ercinjan and Bitlis massifs, with the Central Iran block, and is recorded in the Alborz‐Talesh foldbelt and in Central Iran. Further back‐arc extension in the late Paleocene – Eocene was accompanied by pervasive volcanism and volcaniclastic sedimentation throughout northern and Central Iran. The final closure of NeoTethys and convergence between the Arabian and Eurasian Plates evolved through phases of early Oligocene “soft” collision and middle Miocene “hard” collision. This was accompanied by thrusting in the internal parts of the Zagros foldbelt and by folding and subordinate thrusting in the more external parts, with related development of the flexural Mesopotamian Basin in the foreland to the SW.

Proteomic Analysis and Immunoprofiling of Persian Horned Viper Venom, Pseudocerastes Persicus, from Central Part of Iran.

Numerous species of venomous snakes of medical importance exist in Iran. Pseudocerastes persicus (P. persicus), one of the medically important snakes, also called the Persian horned viper, has a geographical spread that extends to the east, southwest, and central areas of Iran and is endemic across the wider region. As a result, this species is responsible for many snakebite occurrences. Venom from P. persicus found in the central province of Semnan contains phospholipase A2 and L-amino acid oxidase activities, and high toxic potency. The venom was fractionated by reverse-phase high-performance liquid chromatography (HPLC) and analyzed by Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), Western blotting and two-dimensional electrophoresis. Using liquid chromatography with tandem mass spectrometry (LC-MS/MS), a range of components were identified, consistent with the biochemical and toxicological properties of the venom. Proteins identified from 2D electrophoresis and shotgun methods included metallo- and serine proteases, phospholipases, oxidases, and Kunitz trypsin inhibitors, along with many other components at lower qualitative abundance. This study provides a more detailed understanding of the protein profile of Iranian P. persicus venom, which can be effective in the production of an effective antidote against it. The analysis of the resulting data shows that there is a wide range of proteins in the venom of the Persian horned viper. This information can provide a better understanding of how venom is neutralized by polyclonal antivenom. Considering the wide presence of this snake and its related species in Iran and surrounding countries, knowing the venom protein profile of this family can be of great support to antivenom producers such as Razi Vaccine & Serum Research Institute in the preparation of regional antivenoms.

Observed changes in the contribution of extreme precipitation over the Zagros Mountains, Iran

Due to global warming, precipitation regimes are expected to change, and heavy events are expected to occur more frequently. This study investigates the relative share of heavy daily precipitation events to total precipitation for past and current climates. In this regard, daily precipitation data with a spatial resolution of 0.25° × 0.25° from the APHRODITE and CHIRPS databases are used. We used two nonparametric tests, the Mann–Kendall test and Sen’s slope estimator, to identify the trend. The results showed that the frequency of daily heavy precipitation has been increasing in most regions of Iran. The relative share of heavy daily precipitation events to total precipitation has increased over the southwest and central areas of Iran from a case of the past to the current climate. The rise in the share of heavy precipitation of the total precipitation has led to a decrease in the frequency of rainy days (wet days) and an increase in the intensity and concentration of precipitation in Iran. The amount of increase in the share of heavy rainfall to the total precipitation is more prominent in the middle parts of the Zagros Mountains. These conditions lead to heavy floods in the southwestern plains of Iran.

Effect of Micro-Topography and Edaphic Factors on the Asafoetida Volatile Oil Components

Asafoetida volatile oil components (AVOCs) are directly affected by microenvironmental changes. Here, this research aimed to investigate the AVOCs through gradients of micro-topography and edaphic factors in an arid area in central Iran (northern hemisphere) during two consecutive years. Soil and topography data were sampled simultaneously with oleo-gum-resin sampling using 20 plots placed in the area. Data were submitted to a PCA analysis. The AVOCs were significantly affected by both micro-topography and soil properties (P < 0.01). The components of carbonothioic dihydrazide and 1,3,6-0ctatriene, 3,7-dimethyl showed the most negative and positive relationship with the micro-elevation from 0 to 60 cm (R2 = 0.39, 0.44, respectively). Some components showed severe changes depending on the geographical direction, where the highest (42.2%) and lowest (25.1%) values of carbonothioic dihydrazide were obtained under the geographical direction of south and north, respectively. Also, nitrogen, phosphorus, organic matter and silt with R2 = 0.72, 0.52, 0.84 and 0.63, respectively, were positively correlated with some AVOCs, i.e., thiopropionamide and naphthalene, 1,2,3,5,6,8a-hexahy….

Trends of colorectal cancer in a central area of Iran during 2009-2014. An application of joinpoint regression.

IntroductionColorectal cancer (CRC) has become a major public health concern. We analysed current CRC statistics in Arak, including the estimated number of new cases among males and females, age standardized rates (ASRs), and trends for cases diagnosed in the period 2009–2014.Material and methodsIn this study, reported cases of CRC from 2009 through 2014 for Arak residents were obtained from the Arak cancer registry database. We used the direct method to calculate annual ASRs. Joinpoint regression was performed on the ASRs for the whole study period, and we calculated the annual percentage changes (APC).Results533 new CRC cases were included. The annual ASRs of CRC per 100,000 population during 2009–2014 were 13.58 (95% CI: 11.9–15.42), 16.52 (95% CI: 14.62–18.60), 15.00 (95% CI: 13.72–16.35) for females, males, and both genders, respectively. Females had an increasing trend in ASRs (APC: 10.25% and CI 95%: –0.79 to 22.53), and a slightly increasing trend was observed among males (APC = 5.03% and CI 95%: –6.14 to 17.53).ConclusionsThe increasing trend was higher among females than males. These findings raise considerable concern related to a crucial growing public health problem in Arak. They were higher than the averages of ASRs in all of Iran. Furthermore, any increase in the ASRs of CRC may be due to the promotion and improvement in the quality of the cancer registry over time. It is recommended that the quality of the cancer registry is promoted more than the former.

Seasonal trend and source identification of polycyclic aromatic hydrocarbons associated with fine particulate matters (PM2.5) in Isfahan City, Iran, using diagnostic ratio and PMF model.

Particulate matters (PMs) and their associated chemical compounds such as polycyclic aromatic hydrocarbons (PAHs) are important factors to evaluate air pollution and its health impacts particularly in developing countries. Source identification of these compounds can be used for air quality management. The aim of this study was to identify the sources of PM2.5-bound PAHs in Isfahan city, a metropolitan and industrialized area in central Iran. The PM2.5 samples were collected at 50 sites during 1year. Source identification and apportionment of particle-bound PAHs were carried out using diagnostic ratios (DRs) of PAHs and positive matrix factorization (PMF) model. The results showed that the concentrations of PM2.5 ranged from 8 to 291μg/m3 with an average of 60.2 ± 53.9μg/m3, whereas the sum of concentrations of the 19 PAH compounds (ƩPAHs) ranged from 0.3 to 61.4ng/m3 with an average of 4.65 ± 8.54ng/m3. The PAH compounds showed their highest and lowest concentrations occurred in cold and warm seasons, respectively. The mean concentration of benzo[a]pyrene (1.357ngm-3) in December-January, when inversion occured, was higher than the Iranian national standard value showing the risk of exposure to PM2.5-bound PAHs. Applying DRs suggested that the sources of the PAHs were mainly from fuel combustion. The main sources identified by the PMF model were gasoline combustion (23.8 to 33.1%) followed by diesel combustion (20.6 to 24.8%), natural gas combustion (9.5 to 28.4%), evaporative-uncombusted (9.5 to 23.0%), industrial activities (8.4 to 13.5%), and unknown sources (2.8 to 15.7%). It is concluded that transportation, industrial activities, and combustion of natural gas (both in residential-commercial and industrial sectors) as the main sources of PAHs in PM2.5 should be managed in the metropolitan area, particularly in cold seasons.

Heavy metals and related properties in farming soils adjacent to a future copper mine, interpretation using GIS, and statistical methods

Exploitation of mines can lead to the entrance of heavy metals into the environment. There is a possibility of water, soil, and plant pollution in Darreh Zereshk area in the near future. To assess the soil contamination and determine the origin of selected heavy metals, enrichment factor (EF) and geoaccumulation index (Igeo) accompanied with principle factor analysis (PCA) and map of spatial distribution of the elements were conducted. A total of 30 agricultural soil samples and 12 background soil samples were collected from Darreh Zereshk area in central Iran which is going to be one of the richest copper mines in Iran and the Middle East. Total and soluble concentration of heavy metals (Cu, Pb, Zn, Mn, As, Fe, Ni, and Cr) and some physico-chemical properties of soils were determined. The results showed that contamination of the agricultural soils is more severe for Pb, Cu, and Zn and less severe for As. The origin of Ni and Cr did not seem to be anthropogenic. The average concentration of Cu, Pb, Zn, Mn, As, Fe, Ni, and Cr in agricultural soils of the area were 36.87 mg/kg, 190.78 mg/kg, 170.33 mg/kg, 367.41 mg/kg, 69.42 mg/kg, 15494.1 mg/kg, 29.25 mg/kg, and 25.01 mg/kg, respectively. Since the Fe and Mn with geogenic origin were located in the same component with Cu, Zn, Pb, and As; it can be inferred that the source of these elements is controlled by both parent material of soil and anthropic activity.

A new combined framework for sustainable development using the DPSIR approach and numerical modeling

Relying on the conceptual DPSIR framework and MODFLOW analysis, this study used a mixed approach to produce groundwater resource management solutions for the Najafabad area in central Iran. According to DPSIR results, agricultural activities put the highest pressure on groundwater resources in this region. The results showed the effectiveness of reducing water withdrawal over 30 years in maintaining the aquifer in a state of equilibrium. The best scenario consisted of cutting down extraction by 10% over the said period. Output maps of the water table rise at the Najafabad aquifer clearly showed that the groundwater management scenario involving a 10% reduction of water withdrawal was the most effective solution, as it would raise the water level by 6.7 m. Regarding other scenarios, reducing cultivated area by 20% was found to raise the water table by 5.03 m on average, while cutting down water withdrawal by 5% increased the water table by 3.6 m, and a 10% reduction of the cultivated area resulted in a 1.85 m rise. The combined model proposed here can be used for similar aquifers and can aid decision-makers and managers.

Toxoplasma gondii in Milk of Human and Goat from the Desert Area in Central Iran.

Background:Toxoplasma gondii, an obligate intracellular protozoan, causes toxoplasmosis. The aim of this study was molecular detection of T. gondii in breast and goat milk samples by the molecular method in the central Iran.Methods:Totally, 300 human' and 200 goats' milk samples were collected randomly from different regions of central Iran in 2018. DNA extraction was performed by the salting-out method. Molecular detection of the parasite was done by nested-PCR using the specific primer pairs. Statistical analysis was performed by SPSS 23 using descriptive and Chi-square tests.Results:Out of 300 human milk samples, 1 sample (0.3%) was infected with T. gondii. Out of 200 samples of goat milk, 11 samples (5.5%) showed infection with T. gondii. The frequency of infection in goat's milk samples was 4.36% in the south and west, 1.9% in northern regions, and 2% in eastern regions of the province. The statistical analysis showed no significant difference between toxoplasmosis and different geographical regions in the province.Conclusion:Because of the popularity of the goat milk and the transfection probability with the milk to humans, it is recommended to boil milk prior to use. Furthermore, case contamination of T. gondii in the human milk sample showed one of the important paths for infection transmission, which requires further studies.

Knowledge, Attitudes, and Practices Toward Coronavirus Disease 2019 in the Central Area of Iran: A Population-Based Study.

Background: The spread of the coronavirus disease 2019 (COVID-19) pandemic has imposed high threats on global health, life and work style, and social and economic development. The current study aimed to extract knowledge, attitudes, and practices related to COVID-19 among the general population in the central area of Iran.Method: A cross-sectional study was conducted in Arak City between April and May 2020. Stratified random sampling was applied to select the study participants. Phone interview was applied to collect the data. Data were collected using a questionnaire that was constructed and validated in this study. The questionnaire included demographic variables and items about knowledge, attitudes, and practices toward COVID-19. Descriptive and inferential analyses were conducted in STATA software.Results: In total, 544 participants completed the questionnaire; 76% of the participants accounted COVID-19 as a high threat 1 month from the onset of COVID-19. From the maximum attainable scores of 1, 6, and 6, for COVID-19-related knowledge, attitudes, and practices, means of 0.77 (0.13), 4.97 (0.63), and 5.35 (0.70) were obtained, respectively. Females had a higher practice score (5.4 ± 0.6). The participants with a family history of heart and respiratory diseases had significantly higher attitude and practice scores. SMS from the Ministry of Health had a significant impact on knowledge, attitude, and practice scores (p < 0.05).Conclusion: Higher attention should be given to increase the knowledge, attitudes, and practices of men and the housewife group. COVID-19 preventive messaging from the Ministry of Health was among the most influential methods of increasing knowledge that attracted public attention.

State Investment and Empowerment of Local Communities, An Approach to Sustainable Rural Development (Experience of Kashan Rural Area in Central Iran)

Empowerment approach is considered as one of the efficient approaches in rural development activities in Iran through the rural planning system within the framework of five-year programs with government investment in order to achieve sustainable rural development. In this study, it was investigated the role of government investments in empowering villagers, How its effectiveness in the rural area of Kashan was studied. Descriptive-analytical research method and sample population were selected using three-dimensional matrix method of government investment, village location and rural population of 12 villages and 316 rural households. To explain the relationships between independent and dependent variables, Pearson correlation in appropriate statistical environments and for modeling effects, the structural equation model (SEM) in AMOS software was used. Findings indicate a strong, positive and direct relationship between the two variables of investment and rural empowerment (P = 0.000). As the amount of investment increases, the empowerment of the villagers increases. The structural equation model showed that government investment with a factor load of 0.072 has an effect on rural empowerment (RMSEA = 0.036). Following these results in achieving sustainable rural development, the empowerment approach should be considered as a goal and not as a tool. In the experience of government investment in the rural area of Kashan in Central Iran, the investment process was relatively effective and in the future the investment process and implementation of rural projects in general and in arid and semi-arid areas in particular, empowerment and institutionalization approach in Villages are essential.

Evaluating Impacts of Irrigation and Drought on River, Groundwater and a Terminal Wetland in the Zayanderud Basin, Iran

The Zayanderud Basin is an important agricultural area in central Iran. In the Basin, irrigation consumes more than 90 percent of the water used, which threatens both the downstream historical city of Isfahan and the Gavkhuni Wetland reserve—the final recipient of the river water. To analyze impacts of land use changes and the occurrence of metrological and hydrological drought, we used groundwater data from 30 wells, the standardized precipitation index (SPI) and the streamflow drought index (SDI). Changes in the wetland were analyzed using normalized difference water index (NDWI) values and water mass depletion in the Basin was also assessed with gravity recovery and climate experiment (GRACE)-derived data. The results show that in 45 out of studied 50 years, the climate can be considered as normal in respect to mean precipitation amount, but hydrological droughts exist in more than half of the recorded years. The hydrological drought occurrence increased after the 1970s when large irrigation schemes were introduced. In recent decades, the flow rate reached zero in the downstream part of the Zayanderud River. NDWI values confirmed the severe drying of the Gavkhuni Wetland on several occasions, when compared to in situ data. The water mass depletion rate in the Basin is estimated to be 30 (±5) mm annually; groundwater exploitation has reached an average of 365 Mm3 annually, with a constant annual drop of 1 to 2.5 meters in the groundwater level annually. The results demonstrate the connection between groundwater and surface water resources management and highlight that groundwater depletion and the repeated occurrence of the Zayanderud River hydrological drought are directly related to human activities. The results can be used to assess sustainability of water management in the Basin.

Dramatic changes in multiple sclerosis prevalence in Iran: A descriptive study in ten regions of Iran

Background and Objectives: The prevalence of multiple sclerosis (MS) differs between different regions of Iran. This study aimed to investigate changes in prevalence and incidence rates of MS in ten ethnic and cultural zones of Iran set by the Ministry of Health and Medical Education. Materials and Methods: Information on MS incidence and prevalence was obtained from the national registry of MS during the study period 2006–2013. Demographic data were acquired from the Statistical Centre of Iran. Results: A rising trend of MS prevalence was observed in Iran, and overall, the prevalence of MS increased by 3.67% per year. The highest prevalence rates of MS, and the most dramatic increase in MS prevalence, occurred in the central areas of Iran. However, during the 7-year period, the prevalence gradually increased also in southern and western areas. Conclusion: The prevalence and incidence of MS have been rapidly increasing in all regions of Iran, especially from central to western and southern regions.

Triple oxygen isotope variations in magnetite from iron-oxide deposits, central Iran, record magmatic fluid interaction with evaporite and carbonate host rocks

Abstract Oxygen isotope ratios in magnetite can be used to study the origin of iron-oxide ore deposits. In previous studies, only 18O/16O ratios of magnetite were determined. Here, we report triple O isotope data (17O/16O and 18O/16O ratios) of magnetite from the iron-oxide–apatite (IOA) deposits of the Yazd and Sirjan areas in central Iran. In contrast to previous interpretations of magnetite from similar deposits, the triple O isotope data show that only a few of the magnetite samples potentially record isotopic equilibrium with magma or with pristine magmatic water (H2O). Instead, the data can be explained if magnetite had exchanged O isotopes with fluids that had a mass-independently fractionated O isotope composition (i.e., MIF-O), and with fluids that had exchanged O isotopes with marine sedimentary carbonate rocks. The MIF-O signature of the fluids was likely obtained by isotope exchange with evaporite rocks of early Cambrian age that are associated with the IOA deposits in central Iran. In order to explain the triple O isotope composition of the magnetite samples in conjunction with available iron isotope data for magnetite from the deposits, we propose that magnetite formed from magmatic fluids that had interacted with evaporite and carbonate rocks at high temperatures and at variable water/rock ratios; e.g., magmatic fluids that had been released into the country rocks of a magma reservoir. Additionally, the magnetite could have formed from magmatic fluids that had exchanged O isotopes with SO2 and CO2 that, in turn, had been derived by the magmatic assimilation and/or metamorphic breakdown of evaporite and carbonate rocks.

Carboniferous bryozoans from the Kalmard area, central Iran

Four bryozoan species are described from the Siliciclastic Imagh Formation of the Carboniferous (Pennsylvanian) succession at the Imagh section, Posht-e-Badam Block, Kalmard area in central Iran. Three species are new: two trepostomes Dyscritella multiporata sp. nov., Dyscritella kalmardensis sp. nov., and a rhabdomesine cryptostome Rhombopora aryani sp. nov. The species Nikiforovella ambigua Xia and Liu (Rhabdomesina, Cryptostomata) was previously recorded from the Pennsylvanian of China. The generic composition is cosmopolitan for the Carboniferous. The studied bryozoan assemblage indicates middle-to-deep shelf environment.

Bovine cysticercosis in feedlot cattle in central region of Iran.

The cestode, Taenia saginata is a zoonotic tapeworm that it's larval stage which known as Cysticercus bovis cause cyst formation in cattle's organs such as heart, lung, liver, tongue, esophagus and diaphragm muscle, despite the infected cattle may show no clinical signs. Antemortem diagnosis of bovine cysticercosis can be made by antigen detecting ELISA. In a feedlot near city of Arak, beef cattle had different degrees of lethargy, dullness, unthriftiness and were reluctant to move. In postmortem examination of cattle, samples were collected from heart tissue and stained by H&E method for light microscopic examination. 10ml of blood samples were taken from jugular veins of 90 cattle that were going to be sent to slaughterhouse. Serums obtained from blood samples were investigated for presence of C. bovis antigen by ELISA assay. Soils and dusts from farm yard, pen's floor, feed store and both toilets of workers and employer were sampled and evaluated for presence of parasite eggs by floating method. Cysticercus bovis antigen were identified in serums of 18 cattle; and also, samples from workers toilet was contaminated by eggs of T. saginata. This study showed that serologic methods in conjunction with meat inspection can be used for diagnosis of bovine cysticercosis. The aim of this study is to identify infected cattle with C. bovis by serologic methods before slaughter and determine microscopic characteristics of lesions on postmortem examination in central area of Iran.

Polymorphism of IL-12 gene (rs568408G/A) and susceptibility to chronic hepatitis B virus infection in the central area of Iran

Hepatitis B virus (HBV)-related chronicity infection, which is determined by inflammation, is the main etiological factor for this disease. Cytokines are a group of endogenous proteins which have a key role in regulating the inflammatory responses and defeating infectious diseases. IL-12 plays a main role in the clearance of infections especially by viruses such as HBV. Single nucleotide polymorphisms and genetic history have an important role about the level and function of cytokines. The aim of the present study was to investigate the association of IL-12A single nucleotide polymorphism (rs568408 G/A) with chronic HBV infection. In a case–control study, genomic DNA of 148 chronic HBV-infected patients and 80 healthy controls was extracted by salting out method and single nucleotide polymorphism (rs568408 G/A) was genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The frequency of rs568408 G/A gene for GG, GA, AA genotypes was 70.94, 23.6 and 5.7% in chronic patients and 46.25, 42.5 and 11.25% in control group, respectively. After genotyping and statistical analysis, significant difference was seen between the patients with chronic HBV and healthy controls (P = 0.001). Our findings indicated that IL-12A rs568408 can possibly be a risk factor for chronic HBV infection among Iranian population in Yazd province.

Trend of Gastric Cancer Incidence in an Area Located in the Center of Iran: 2009-2014.

There are remarkable differences between the incidence and mortality of gastric cancer in different places of the world. This study, for the first time, estimated the information around the incidence rates and trends of gastric cancer in the central area of Iran, Arak metropolitan. In this study, all cases with gastric cancer in Arak from 2009 to 2014 were included. Direct standardized method was applied to estimate age-standardized incidence rates (ASIRs) by a STATA package, with efficient interval estimation that might be preferable in the case of rare diseases, including cancer data. The obtained standard errors were used to calculate annual percent changes (APCs) by the Joinpoint analysis. Annual ASIRs of gastric cancer were 23.92 (95% CI 21.62, 26.37) and 9.60 (95% CI 8.20, 11.18) for male and female, respectively. In male, APC of ASIRs was - 5.00% (95% CI - 9.32, - 0.47). In contrast, among female, it was - 2.69% (95% CI - 31.56, 38.34) that was statistically insignificant. The ASIRs have significantly decreased trends in males, but not in females. The preventive strategies should be a focus on the declining of the risk factors and the quick early diagnosis of gastric cancer.

Reference Intervals for Thyroid Hormones During the First Trimester of Gestation: A Report from an Area with a Sufficient Iodine Level.

The physiological changes during pregnancy modulate the endocrine system. Therefore, both the American and the European thyroid associations recommend the use of local trimester-specific reference intervals. The purpose of this study was to establish the first trimester reference intervals for thyroid function tests in the central area of Iran. We examined 436 pregnant women in their first trimester of pregnancy, and 444 non-pregnant women in a cross sectional study. Serum levels of thyroid stimulating hormone (TSH), free thyroxin (FT4), free triiodothyronine (FT3), thyroid peroxidase antibody, urinary iodine concentration (UIC), and thyroid volume were measured for all subjects. The first trimester-specific reference intervals (2.5th-97.5th percentile) were determined for 185 pregnant women and 256 non-pregnant women with negative TPOAb, adequate iodine level (UIC≥150 μg/l in pregnant and UIC≥100 μg/l in non-pregnant women), and normal thyroid examination. We calculated multiples of the median (MoM) for TFTs to normalize the obtained data. The first trimester-specific reference intervals of serum TSH, FT4, and FT3 for pregnant women were 0.20-4.60 mIU/l, 9.0-18.02 pmol/l, and 3.40-5.64 pmol/l, respectively, while the corresponding figures for non-pregnant women were 0.59-5.60 mIU/l, 9.52-19.30 pmol/l, and 3.70-5.55 pmol/l, respectively. The first and 99th percentile MoM of TSH in pregnant women in their first-trimester was 0.06-4.62. The local normal reference ranges for the first trimester of pregnancy in central region of Iran were different from the ranges suggested by the ATA.