27 research outputs found

    PROCJENA ČVRSTOĆE I PETROFIZIČKIH SVOJSTAVA ANHIDRITNE KROVINE NA TEMELJU PROMJENJIVIH OPTEREĆENJA I RAČUNALNE TOMOGRAFIJE

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    Underground gas storage (UGS) in depleted reservoirs affects caprock properties. The resemblance of Qom anhydrite outcrop with cutting obtained from a 2629 m depth was confirmed using X-ray diffraction (XRD) results and scanning electron microscope (SEM) tests. The anhydrite specimens unconfined compressive strength (UCS) changed under static cyclic loading conditions, and also petrophysical properties, such as porosity and permeability altered under 10, 20, and 30 cycles of loading. The magnitude of loading ranged from 30 to 43% of intact anhydrite UCS. The loading rate used for cyclic loading tests was 0.004 mm/s. The samples’ UCS decreased between 3.5 to 23.9% under cyclic loading conditions. The study of specimens computed tomography (CT) imaging with porosity and permeability indicated the growth of cracks, the cracks did not initiate in all lengths of specimens, hence the incremental increase in porosity did not increase the permeability of specimens. Even being under cyclic loads, the permeability of specimens stayed lower than 10-15 m2 (0.001 mD) but the trend of pressure versus time for measuring permeability shows a higher drop in pressure due to changes in permeability. The study indicated that the CT imaging results are in good accordance with petrophysical findings.Podzemno skladište plina smješteno u iscrpljenim ležištima utječe i na svojstva krovine. Sličnost između anhidrita Qom uzorkovanoga na površinskome izdanku te iz krhotina dobivenih s 2629 m dubine opisana je na temelju rezultata difrakcije x-zraka i skeniranja elektroničkim mikroskopom. Maksimalna jednoosna tlačna čvrstoća uzorka anhidrita mijenja se u uvjetima statičkih, promjenjivih, cikličkih opterećenja, pri čemu dolazi i do promjene petrofizičkih svojstava poput šupljikavosti i propusnosti, npr. tijekom 10, 20 i 30 ciklusa. Magnituda opterećenja bila je u rasponu od 30 do 43% maksimalne tlačne čvrstoće anhidrita, dok je intenzitet opterećenja kod cikličkih testova iznosio 0,004 mm/s. Kod ispitivanih uzoraka zamijećeno je smanjenje maksimalne tlačne čvrstoće u rasponu od 3,5 do 23,9% pri različitim uvjetima promjena opterećenja. Proučavanjem šupljikavosti i propusnosti uzoraka i snimki računalne tomografije vidljiv je porast broja pukotina u uzorku, pri čemu je uočeno da do stvaranja pukotina nije došlo uzduž cijeloga uzorka, kao što niti porastom šupljikavosti nije došlo do rasta propusnosti. Iako su uzorci bili izloženi cikličkim opterećenjima, propusnost uzoraka ostala je manja od 10-15 m2 (0,001 mD). Proučavanjem promjene tlaka u vremenu uočen je veći pad tlaka zbog promjene propusnosti uzorka. Rezultati istraživanja upućuju na dobro podudaranje podataka dobivenih snimkama računalne tomografije i rezultata petrofizičkih ispitivanja

    Study of three common mitochondrial mutations in Arab patients with nonsyndromic hearing loss in Khuzestan province, I.R.Iran

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    زمینه و هدف : ناشنوایی یکی از شایع ترین اختلالات حسی –عصبی است که در هر 1000 تولد زنده رخ می دهد. بیشتر ناشنوایی ها منشا ژنتیکی داشته و حدود 2-0 موارد ناشنوایی مربوط به جهش در ژن های میتوکندریایی است. این مطالعه با هدف بررسی فراوانی سه جهش میتوکندریایی A1555G ، A3243G و A7445G در ناشنوایان غیر سندرمیک استان خوزستان انجام شده است. روش بررسی: در این مطالعه توصیفی 62 دانش آموز ناشنوای غیر سندرومیک با الگوی اتوزومی مغلوب عرب استان خوزستان به روش آسان انتخاب شدند. DNA با روش استاندارد فنل کلروفرم استخراج و جهش های احتمالی در سه ژن میتوکندریایی شامل A1555G ، G3243A و A7445G با روش چند شکلی طول قطعه محدود ( PCR-RFLP ) غربالگری شد. در نهایت جهش های احتمالی به روش توالی یابی مستقیم مورد بررسی و تائید قرار گرفتند. یافته ها: در این مطالعه هیچ یک از جهش های A1555G ، A3243G و A7445G یافت نشد، با این حال دو جهش G3316A و A7445C در دو بیمار مورد مطالعه یافت شد. نتیجه گیری: این مطالعه نشان می دهد که جهش های میتوکندریایی G3316A و A7445C مسئول تعداد کمی از ناشنوایی های قبل از زبان باز کردن در جمعیت استان خوزستان می باشند و جهش های A1555G ، A3243G و A7445G در ایجاد ناشنوایی در این جمعیت نقشی نداشته اند. مطالعه ی حاضر خواهد توانست مشاوران ژنتیک در استان خوزستان را در برنامه مشاوره ژنتیک ناشنوایی خانواده ی بیماران ناشنوا یاری کند

    Genetic Linkage Analysis of 15 DFNB Loci in a Group of Iranian Families with Autosomal Recessive Hearing Loss

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    Background: Hearing loss (HL) is the most frequent sensory birth defect in humans. Autosomal recessive non-syndromic HL (ARNSHL) is the most common type of hereditary HL. It is extremely heterogeneous and over 70 loci (known as DFNB) have been identified. This study was launched to determine the relative contribution of more frequent loci in a cohort of ARNSHL families. Methods: Thirty-seven Iranian families including 36 ARNSHL families and 1 family with Pendred syndrome each with >= 4 affected individuals, from seven provinces of Iran, were ascertained. DFNB1 contribution was initially studied by DNA sequencing of GJB2 and linkage analysis using the relative STR markers. The excluded families were then subjected to homozygosity mapping for fifteen ARNSHL loci. Results: Sixteen families were found to be linked to seven different known loci, including DFNB I (6 families), DFNB4 (3 families +1 family with Pendred syndrome), DFNB63 (2 families), DFNB2 (1 family), DFNB7/11 (1 family), DFNB9 (1 family) and DFNB21 (1 family). DNA sequencing of the corresponding genes is in progress to identify the pathogenic mutations. Conclusion: The genetic causes were clarified in 43.2% of the studied families, giving an overview of the causes of ARNSHL in Iran. DFNB4 is ranked second after DFNB1 in the studied cohort. More genetic and epigenetic investigations will have to be done to reveal the causes in the remaining families

    Common Aeroallergens in Patients with Asthma and Allergic Rhinitis Living in Southwestern Part of Iran: Based on Skin Prick Test Reactivity

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    Aeroallergens continue to have a key role in the pathogenesis of asthma and allergic diseases and have recently received increased attention in medical research throughout the world. The prevalence of aeroallergens vary in different regions, depending on the type of climate. The aim of the present study was to determine prevalence of the sensitivity to aeroallergens among patients with asthma and allergic rhinitis (AR), based on skin prick test (SPT) reactivity in the province of Bushehr, Iran. In this cross-sectional study, 743 patients were enrolled. The participants had asthma and AR and reacted to at least one allergen with SPT. Skin prick test with standard extracts including house dust mites (HDMs), animal dander, molds and pollens were performed on patients according to the herbal geography of the area. The male to female ratio and mean age of the patients were 1.03 and 27.6± 15.4 year, respectively. Out of 567 patients with AR, the common aeroallergens were HDMs (88.5%), molds (82.9%), animal dander (79.5%), weeds (77.6%), trees (75.5%) and grass pollen (71.5%). Moreover, among 176 patients with asthma, the prevalence of aeroallergens were HDMs (90.5 %), molds (80.7%), animal dander (77.5%), weeds (73.3%), trees (73.3%) and grass pollen (67.9%). The sensitivity to animal dander, Chenopodium album and Russian thistle pollens were significantly associated with the severity of AR. Moreover, sensitivity to animal dander such as cat and feather of birds, cockroach, Bermuda grass and Chenopodium album pollens were significantly associated with the severity of asthma. The results of this study revealed that HDM was the most common sensitizing aeroallergen in patients with asthma and AR. Molds and animal dander as indoor allergens were also common aeroallergens. We suggest that the hot weather and ambient humidity in the region may be the main cause of the change in the pattern of SPT reactivity

    Mutation screening of GJB2 and GJB6 and genetic linkage study of three prevalent DFNB loci in Iranian families with autosomal recessive non-syndromic hearing loss

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    Background and aim: The incidence of prelingual hearing loss (HL) is about 1 in 1000 neonates of which, more than 60% of cases are inherited. Non-syndromic HL (NSHL) is extremely heterogeneous: more than 100 loci have been identified. The most common form of NSHL is the autosomal recessive form (ARNSHL). Here, we have investigated CX26 (GJB2) and CX30 (GJB6) gene mutation and linkage analysis of 3 known loci in Iranian families. Methods: A cohort of 36 big ARNSHL pedigrees from 7 provinces of Iran was investigated. All of the families were examined for the presence of GJB2 and GJB6 (del D13S1830 and del D13S1854) mutations using direct sequencing and multiplex PCR, respectively. The negative mutations pedigrees for the above- mentioned mutations, were then tested for the linkage to the 3 known loci, including DFNB3(MYO7A), DFNB4(SLC26A4) and DFNB7/11(TMC1), using STR markers and conventional PCR and PAGE. Results: Six families had GJB2 mutations. No GJB6 mutation was found. Totally, 3 families showed linkage to DFNB4 and 1 family was linked to DFNB7/11. Conclusion: DFNB1 (GJB2) and DFNB4 are the main causes of ARNSHL in our study samples and GJB6 mutations are apparently absent in the Iranian populatio

    Screening of three common mtDNA mutations among subjects with autosomal recessive non-syndromic hearing loss in Sistan va Baluchestan province, Iran

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    Background: Non-syndromic hearing loss may be induced by mutations in both nuclear and mitochondrial genes. Mutations in mtDNA are present in less than 1% of the children with pre-lingual deafness but are more prevalent later. Most of the molecular defects responsible for mitochondrial disorder, associated with hearing loss may be induced by mutations in the 12SrRNA and tRNA genes. This aim of this study was to investigate the frequency of three common mtDNA mutations including A1555G, A3243G and A7445G in a cohort of autosomal recessive non-syndromic hearing loss (ARNSHL) subjects in Sistan va Baluchestan province. Material and Methods: In this descriptive- experimental based study, a total of 110. ARNSHL subjects from Sistan va Baluchestan province were investigated for three common mtDNA mutations using PCR-RFLP procedure. The possible mutations were confirmed by direct sequencing. Results: None of the A1555G and A7445G mutations were detected in this study. However, we found one sample to carry A3243G mutation (0.9%). Moreover abolishing a MTTL1 restriction site close to A3243G mutation revealed a G3316A allelic variant in 0.9% of patients studied. Conclusion: This study showed that mtDNA mutations are responsible for less than 1% of pre-lingual ARNSHL associated subjects. The present study will improve the genetic counseling of hearing impaired patients in Sistan va Baluchestan province, Iran

    Dusty Air Pollution is Associated with an Increased Risk of Allergic Diseases in Southwestern Part of Iran

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    Concerns have been raised about the adverse impact of dusty air pollution (DAP) on human health. The aim of this study was to find the association between dusty air pollution based on air quality index (AQI) and the risk of allergic diseases in southwestern provinces of Iran, with assessing cytokine profiles and lymphocyte immunophenotypes. In this case control study 148 individuals participated. The sampling was done in hazardous condition (AQI >300) as the case and clean air (AQI <50) as the control. We measured cytokine production by using ELISA method and phenotypes of T-lymphocytes (CD4+ and CD8+), CD19+ B-lymphocytes, CD25+, CD4+ CD25+ cells by FACSort flow cytometer. The mean serum level of IL-4 (33.4±2.9 vs 0.85± 0.65 pg/dl) and IL-13 (15.1±4.4 vs. 0.12±0.7 pg/dl) in the subjects exposed to ambient DAP was increased significantly compared to the individuals in the clean air condition. Also, CD19+ B-lymphocytes (12.6± 4.9 vs 8.9±3.2%) and CD4+ CD25+ cell count (13.6± 4.6 vs 7.7± 3.8%) in peripheral blood were increased significantly in subjects exposed to ambient DAP compared with the controls. The result of our study suggested that ambient DAP affected immune system in a way that might lead to allergic diseases in the population

    Serum-based metabolic alterations in patients with papillary thyroid carcinoma unveiled by non-targeted 1H-NMR metabolomics approach

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    Objective(s): As the most prevalent endocrine system malignancy, papillary thyroid carcinoma had a very fast rising incidence in recent years for unknown reasons besides the fact that the current methods in thyroid cancer diagnosis still hold some limitations. Therefore, the aim of this study was to improve the potential molecular markers for diagnosis of benign and malignant thyroid nodules to prevent unnecessary surgeries for benign tumors. Materials and Methods: In this study, 1H-NMR metabolomics platform was used to seek the discriminating serum metabolites in malignant papillary thyroid carcinoma (PTC) compared to benign multinodular goiter (MNG) and healthy subjects and also to better understand the disease mechanisms using bioinformatics analysis. Multivariate statistical analysis showed that PTC and MNG samples could be successfully discriminated in PCA and OPLS-DA score plots. Results: Significant metabolites that differentiated malignant and benign thyroid lesions included citrate, acetylcarnitine, glutamine, homoserine, glutathione, kynurenine, nicotinic acid, hippurate, tyrosine, tryptophan, β-alanine, and xanthine. The significant metabolites in the PTC group compared to healthy subjects also included scyllo- and myo-inositol, tryptophan, propionate, lactate, homocysteine, 3-methyl glutaric acid, asparagine, aspartate, choline, and acetamide. The metabolite sets enrichment analysis demonstrated that aspartate metabolism and urea cycle were the most important pathways in papillary thyroid cancer progression. Conclusion: The study results demonstrated that serum metabolic fingerprinting could serve as a viable method for differentiating various thyroid lesions and for proposing novel potential markers for thyroid cancers. Obviously, further studies are needed for the validation of the results

    Prevalence and Risk Factors of Asthma and Allergic Diseases in Primary Schoolchildren Living in Bushehr, Iran: Phase I, III ISAAC Protocol

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    Asthma and allergic diseases present a major health burden. Information on the prevalence of these diseases indicates that these diseases are increasing in various parts of the world. It was hoped that this study would be helpful to health system policy-makers in planning allergy prevention programs in the region. The prevalence of asthma and allergic diseases and relation between the various risk factors involved were assessed among schoolchildren in the city of Bushehr, Iran. The ISAAC Phase I and III questionnaires were completed by parents of 1280 children aged 6-7 years and self-completed by 1115 students aged 13-14 years. The prevalence of atopic eczema, allergic rhinitis and asthma among 6-7 year-old students were 12.1%, 11.8% and 6.7%, respectively. While, the prevalence of these diseases among 13-14 year-old students were found to be 19%, 30% and 7.6%, respectively. There was an association between asthma and allergic rhinitis as well as eczema (p<0.05). Consumption of fast food as a risk factor was significantly associated with asthma (p=0.03). The prevalence of asthma and allergic diseases was high among schoolchildren in the city of Bushehr, Iran. Also an association was observed between the fast food consumption and asthma. Keywords: Allergic rhinitis; Asthma, Atopic eczema; Children; ISAAC; Prevalenc

    DFNB59 Gene Mutation Screening Using PCR-SSCP/HA Technique in Non-syndromic Genetic Hearing Loss in Bushehr Province

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    Background: Hearing impairment (HI) is the most prevalent Neurosensory disorder which is heterogenous and can also occur due to environmental causes. The majority of hearing deficiencies are of genetic origin affecting about 60% of the HI cases. A novel gene DFNB59 encodes pejvakin has been recently shown to cause deafness. This study aims to determine the frequency of DFNB59 gene mutations in coding region the gene in Bushehr province. Methods: In this descriptive experimental study, we investigated the presence of DFNB59
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