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Earthquakes usually occur after some preliminary anomalies in the physical and chemical characteristics of environment and earth interior. Construction of the models which can explain these anomalies, prompt scientists to monitor geophysical and geochemical characteristics in the seismic areas for earthquake prediction. A review of studies has been done so far, denoted that radon gas shows more sensitivity than other geo-gas as a precursor. Based on previous researches, radon is a short-term precursor of earthquake from time point of view. There are equal experimental equations about the relation between earthquake magnitude and its effective distance on radon concentration variations. In this work, an algorithm based on Dobrovolsky equation $$ (D = 10^{0.43M} ) $$ with defining the Expectation and Investigation circles for great Tehran has been used. Radon concentration was measured with RAD7 detector in the more than 40 springs. Concentration of radon in spring, spring discharge, water temperature and the closeness of spring location to active faults, have been considered as the significant factors to select the best spring for a radon continuous monitoring site implementation. According to these factors, thirteen springs have been selected as follow: Bayjan, Mahallat-Hotel, Avaj, Aala, Larijan, Delir, Lavij, Ramsar, Semnan, Lavieh, Legahi, Kooteh-Koomeh and Sarein. [ABSTRACT FROM AUTHOR]

The top-down in situ combustion (ISC) involves the stable propagation of the combustion front from the top vertical injector to the bottom horizontal producer. Apart from laboratory studies in conventional sandstones, no application of the process in fractured carbonates has been addressed yet. The authors modified a successful combustion tube history matched model of an Iranian low-permeable heavy oil reservoir called Kuh-E-Mond to investigate the feasibility of ISC in fractured carbonate reservoirs mimicking block-scale combustion cells. Effects of fractured geometrical properties such as orientation, location, extension, density, spacing, and dispersion were considered. Results confirmed a higher outcome in the case of optimum vertical or horizontal fracture density and spacing. Vertical fractures located at the lateral sides of the cell enhanced the process in terms of ultimate oil recovery and oxygen sweep efficiency. The longer vertical fractures and higher dispersion through the reservoir improved the recoveries compared with the lower efficiency in the case of extended horizontal fractures and raised their dispersion through the reservoir. Simulation analysis confirmed that top-down ISC has higher feasibility in the case of highly networked fractures through reservoirs such as those in the Persian Gulf coast. [ABSTRACT FROM PUBLISHER]

Three species of dotillid crabs, Dotilla blanfordi Alcock, 1900, Ilyoplax frater (Kemp, 1919), and Scopimera crabicauda Alcock, 1900, which were collected in 2009 and 2010 from intertidal zones on the coasts of the province of Sistan and Baluchistan, Iran, are new records for the northern Gulf of Oman. The diagnostic characteristics of these species were examined and are reported upon in this paper. [ABSTRACT FROM AUTHOR]

Background: Although, family history of cancer is an important risk factor for upper gastrointestinal cancers development, but limited information is available on the upper gastrointestinal cancers associated with family history in Iran. The purpose of this study was to define upper gastrointestinal cancers risk associated with family history of cancer. Methods: This study was conducted as a case control study. A total number of 1,010 cases of upper gastrointestinal cancer and 1,010 healthy controls were recruited. For family history of cancer, questions were asked about any malignant tumor in first and second degree relatives. Adjusted odds ratio estimates for the association family history and upper gastrointestinal cancers risk and corresponding 95% confidence intervals were obtained. Results: A family history of any malignant tumor in relatives was associated with 1.3 fold increased risks of upper gastrointestinal cancers. A first-degree family history of esophageal and gastric cancer was significantly associated with upper gastrointestinal cancers development, with an adjusted OR of 4.7(CI 95%: 2.6-8.4). Conclusion: Our findings suggested that risk for upper gastrointestinal cancers increases among individuals with family history of cancer. Therefore, appropriate screening strategies especially in relatives of patients should be considered to prevent and control of disease. [ABSTRACT FROM AUTHOR]

Background: Clinical and epidemiological variation was seen between the colon cancer (CC) and rectum cancer (RC). So, there is not so much data available about the epidemiological and clinicopathological differences and prognostic factors regarding to CC and CR in Iran, we aimed to perform this study. Methods: All cases of CC and RC referred to oncology and gastroenterology wards of Taleghani General Hospital, Teheran, Iran between 2002 and 2008 were retrospectively reviewed. The research group were reviewed all medical records in the study period for collecting the required data. All patients under study were followed up until end day of 2008 (closed day) from their diagnosis. Results: There are 856 cases of CC and 427 cases of RC. Mean survival time of CC cases was relatively higher than RC cases (P <0.05). Regarding to the age at diagnosis, about 42% of CC and 42.6% of RC patients was diagnosed less than 50 years of age. Positive family history of any cancer was relatively higher in CC (40.0%) patients than RC (31.0%) patients (P<0.05). significant difference was seen between CC and RC regarding to depth of tumor invasion, pathologic stage and type of first treatment. RC patient were diagnosed in more advanced pathologic stages. Regarding to histology type of tumor 75.0% of CC cases and 79.4% of RC cases was adenocarcinoma. Abdominal pain (74.4%) and blood per rectum (89.7%) were the most prevalent symptoms mentioned by patients for CC and RC, respectively. Distant metastasis, lymph node metastasis, lower BMI and poor grading of tumor was related to increased risk of death due to CC. Regarding to RC, only pathologic stage was determine as prognostic factor. Conclusion: Results of this study emphasis that RC has a poorer prognosis comparing to CC. Up to 42 percent of patients with CC and RC are lower than 50 years of age. Patterns of CC versus RC indicate major variations in demographic and clinicopathologic characteristics that suggest possible differences in etiology and pathogenesis. So we suggest that for the analysis of cancer data, CC and RC should be investigated as separate cancers and not to be as colorectal cancer. Abdominal pain and blood per rectum should be emphasis for detection of CC and RC, respectively. [ABSTRACT FROM AUTHOR]

BACKGROUND: In around 10 to 15% of all colorectal cancer (CRC) cases, a positive family history of colorectal cancer is observed. Although increased risk of colorectal cancer in individuals with a family history of the disease has been observed consistently in the past studies, limited information is available on colorectal cancer associated with family history in Iran. AIMS: The purpose of this study is to define the risk of colorectal cancer associated with a family history of cancer. SETTING AND DESIGN: The present study was designed as an unmatched case control study. The cases were 393 patients with histologically confirmed colorectal carcinomas and there were 393 controls, randomly selected from among the healthy participants in a health survey. METHODS: The family history was extracted from a standard history form completed by the patient or from the record created by a health care provider. STATISTICAL ANALYSIS: Mantel-Heanszel Odds Ratio was computed for removing the confounding effect of age and sex. RESULTS: A positive family history of cancer was reported by 36.4 and 24.4% among the cases and controls, respectively. Colorectal cancer risk increased two-fold in subjects who reported having first degree relatives with cancer. The adjusted odds ratio was 4.76, indicating that having a positive family history of colorectal cancer among relatives increased one's risk of colorectal cancer about 4.5-fold. CONCLUSION: According to our findings, a family history of cancer increased the risk of CRC. Due to this fact that there is no current colorectal cancer screening program in Iran, it is recommended that first degree relatives of patients with colorectal cancer should be considered as a priority group for screening programs. [ABSTRACT FROM AUTHOR]

In order to understand the bioaccumulation of mercury in fish in the Iranian coastal waters of the Caspian Sea and the Persian Gulf, different fish species were sampled from both regions in January 2002. Mullet fishes were sampled from the Caspian Sea and six other species from the Persian Gulf: Largetooth flounder, Spotfin flathead, Japanese threadfin bream, Greater lizardfish, Elongate sole and Giant seacatfish. In the Persian Gulf, total Hg concentrations in fish ranged from 0.0123 to 0.0867 mg kg−1 w.w. (0.0614 to 0.433 mg kg−1 d.w.). Methylmercury accounts for 64–100% of the total mercury. Highest mercury concentrations were observed in the predatory fish: Giant seacatfish, Threadfin bream and the larger Greater lizardfish caught near Mogham Port. In these species the methylmercury fraction is always higher than 90%. A low methylmercury fraction was only observed in the smallest specimen of flounder and Elongate sole. In the Caspian Sea Hg concentrations in Mullet ranged from 0.0102 to 0.108 mg kg−1 w.w. The observed concentrations are comparable to those found in other areas of the Persian Gulf as well as in other marine environments and are much lower then the WHO guideline of 0.5 mg kg−1 w.w. [ABSTRACT FROM AUTHOR]

Neuropeptide Y (NPY) and gonadotrophin-releasing hormone receptor (GnRHR) are two candidate genes with a wide variety of physiological functions in growth and especially in reproduction processes. We examined the association of one SNP from each of these genes with growth- and egg production-related traits in Mazandaran native chickens. Two hundred and six individuals were genotyped by PCR-RFLP. Marker-trait association analyses were performed using both breeding value and phenotypic information. The data came from 18 successive generations of selection at a Mazandaran native chicken breeding station in Iran. Data were analyzed with a univariate animal model in an ASREML procedure to estimate breeding values of the birds for these traits. Two alleles were found for both genes, A and a alleles for GnRHR, with frequencies of 0.614 and 0.386, B and b alleles for NPY, with frequencies of 0.780 and 0.221, respectively. The additive genetic effects of the GnRHR gene on egg number and egg mass were significant. Also, body weight at sexual maturity was significantly influenced by the NPY gene. We conclude that GnRHR and NPY genes are associated with egg production and growth traits, respectively.

Introduction: Esophageal cancer is the 6th most common cause of cancer death in the world. During the past two decades some changes have occurred in histologic type and primary tumor location in some parts of the world but there is a little information about histopathological aspect of disease in Iran. The purpose of the present study was to clarify the features of histopathological of esophageal cancer in Iran., Methods: This study designed as a cross sectional study. Data analysis was performed with descriptive and univariate methods. Information required for this study extracted from cancer registry forms. The cases were all patients who received a histopathological diagnosis of EC that were referred to this center from January 2003 to October 2008., Results: A total of 264 EC cases were recruited in the study the lower third of the esophagus was the most frequent site of origin of these tumors. Squamus cell carcinoma was commonest histologic type of tumor. In 15.2% of cases tumor was metastasis to other organs. In 46.6% were in advanced stage at diagnosis., Discussion: Based on result of present study, esophageal cancer in our country more presented in Squamus cell carcinoma histology type, in advanced stage. Since Squamus cell carcinoma have a poorer prognosis and given that these patients have vague symptomatology for approximately several months, therefore, early diagnosis and treatment led to better prognosis.

Type 1 diabetes mellitus (T1DM) is one of the T-cell mediated autoimmune diseases and vitamin D suppresses activation of T-cell and has immunomodulatory effects. In this study the association between four vitamin D receptor (VDR) gene polymorphisms, at positions FokI, BsmI, ApaI and TaqI, and susceptibility to T1DM was investigated. We assessed 87 Iranian patients with T1DM and one hundred healthy controls with no history of diabetes or other autoimmune diseases. Our results demonstrated that genotypes frequency of the TaqI VDR polymorphism differed significantly between T1DM patients and controls, TT genotype and T allele was more frequent in healthy controls compared with TIDM patients (P = 0.003; OR = 0.51, 95% CI = 0.31-0.84). Therefore, allele t is the risk-allele for developing TIDM in this study. No significant association was observed between others VDR SNPs and disease susceptibility. In conclusion, our case-control study indicated that the VDR TaqI polymorphism is associated with TIDM in Iranian population.

Introduction: Gastric cancer is one of the major causes of cancer related death in the world. A number of risk factors are now known to be related to the development of the disease. Previous reports indicated that a family history is a serious risk, but there is a little information about this in Iran. The aim of this study was to explore the relation between family history of cancer in first and second degree relatives and the risk of GC in Iran., Methods: The present study was designed as unmatched case control study. Cases were 746 patients with histologically confirmed GC and the 746 controls were randomly selected among the healthy participants in a health survey. Family history was extracted from a standard history form completed by the patient or from records created by a health care provider. Mantel-Heanszel odds ratios were computed for removing the confounding effect of age and sex., Results: Overall, 9.7% of cases versus 5.6% of controls reported a family history of GC. Risk increased over twofold for this group. There was no significant association among family history of other cancers and GC (P>0.05)., Conclusion: In conclusion, this study showed that family history of GC, especially in first-degree relatives, increases the risk of development of the disease. Further studies are needed to better understand the roles of genetic and environmental factors and their interaction in gastric cancer development in the Iranian community.

Aims and Background: Mucinous adenocarcinoma (MA) colorectal cancer accounts for 10 to 15% of colorectal carcinoma. It is generally thought that patients with MA present at a more advanced stage of disease and have a poorer prognosis than those with other types of carcinoma. The purpose of the present study was to clarify the clinicopathological characteristics of mucinous colorectal carcinoma in the Iranian population., Methods: Between January 2002 and March 2008, Of the 1283 colorectal cancer patients, 110 patients were considered to have mucinous tumors according to pathology report. Patients evaluated on the basis of sex, age, location of tumor, stage, differentiation of tumor and family history of cancer. Kaplan-Meier curves and log-rank tests were used for survival analysis., Results: The median age of these patients at diagnosis was 50.07 years. More than 50% of patients were younger than aged 50 years. 34.5% of patients had a family history of colorectal cancer in their first-degree relatives. Most tumors were presented in right colon. 54.3% of MA patients had advanced stage lesions. The Kaplan-Meier method indicated that, the 1, 3 and 5 year survival rates are 92.6, 80.1 and 41.3 percent, respectively. Survival of the patients was related to disease stage (P = 0.023)., Conclusion: Our suggests that genetic factors may be play an important role in the development of this disease in our country and screening programs, especially genetic screening programs, should be considered as a main measure for prevention and control of colorectal cancer in Iran.

Background: Colorectal cancer (CRC) is one of the most malignant cancers, but prognosis varies in different parts of the world. Knowing the prognostic factors of the cancer is clinically important for prognosis and treatment application objectives. However, evaluation of these factors overall does not provide thorough understanding of the cancer. Therefore, this study aimed to evaluate prognostic factors of colon and rectal cancers site-specifically, via a competing risks survival analysis with colon and rectum as competing causes of death., Methods: A total of 1,219 patients with CRC diagnosis according to the pathology reports of our cancer registry, from 1 January 2002 to 1 October 2007, were entered into the study. Demographic and clinicopathological factors with regard to survival of patients were analyzed using univariate and multivariate competing risks survival analysis, utilizing STATA statistical software., Results: The results of univariate analysis showed that gender, body mass index (BMI), alcohol history, inflammatory bowel disease (IBD), tumor size, tumor grade and pathologic stage were significantly associated with colon cancer and BMI, personal history of cancer, pathologic stage and the kind of first treatment used were significantly related to rectal cancer. In the multivariate analysis, BMI, IBD, tumor grade and pathologic stage of the cancer were significant prognostic factors for colon cancer and BMI and the kind of first treatment used were significant prognostic factors of rectal cancer. Also 1, 2, 3, 4 and 5 year and overall adjusted survival of patients with rectal cancer was better than those of colon cancer., Conclusion: Based on our findings, CRC is not a single entity and its sub-sites should be evaluated separately to reveal hidden associations which may not be revealed under general modeling.

In this study, trophic state indicators, total phosphate, algal chlorophyll and Secchi disk transparency and zooplankton community of Lake Choghakhor was studied monthly between May 2003 and April 2004. This lake is a shallow ecologically and economically important water body in eastern part of Iran. Crop farming and recreational activities are examples of the human impact around and within the lake, leading to a loading of DIN (Dissolved Inorganic Nitrogen) and TP (Total Phosphate) into the lake. Now submerged plants especially Myriophyllum spicatum has covered almost the entire lake and dense macrophyte beds (Polygonom amphibium), located on the East Southern end of the lake appear to act as a sink for these nutrients. Lake Choghakhor appeared to be in a macrophyte dominated clear water state with low TP (annual mean: 24 +/- 15 microg L(-1)) and chlorophyll a (annual mean: 3 +/- 1.28 microg L(-1)) concentrations and very high Secchi depth. The grazing pressure of dominant pelagic filtering zooplankton Daphnia longespina did not seem to be significant in determining the low phytoplankton crop expressed as chlorophyll a. We expect that sequestering of nutrients by submerged plants and associated epiphytes are the dominant stabilizing mechanisms suppressing the phytoplankton crop of Lake Choghakhor.

The composition of essential oil extracted from Valeriana officinalis L. roots growing wild in Iran was studied by hydrodistillation and supercritical CO2 extraction. Forty-seven components representing 89.3% and 35 constituents varying from 86.1% to 95.1% of the oil obtained by hydrodistillation and supercritical CO2 were identified, respectively. The major components in the extracted oil from supercritical CO2 were isovaleric acid (18.7-41.8%), valerenic acid (8.2-11.8%), acetoxyvaleranone (5.6-9.6%), (Z)-valernyl acetate (4.5-6.5%), bornyl acetate (2.3-7.7%) and valerenol (3.7-5.2%), whereas by hydrodistillation were bornyl acetate (11.6%), valerenic acid (8.0%), (Z)-valernyl acetate (7.9%) and acetoxyvaleranone (7.6%). The analysis of the extracts was performed by capillary GC and GC/MS.