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21.
Mostafa Abedi-Tizaki 《Archives Of Phytopathology And Plant Protection》2013,46(8):676-687
In order to determine the crown and root agents and their mycotoxins produced in different growth stages of wheat including seedling, tillering and heading, sampling was done in north of Iran, during 2011–2012. From 160 isolates of Fusarium, eight species were obtained including F. graminearum, F. culmorum, F. equiseti, F. nygamai, F. semitectum, F. solani, F. acuminatum and F. oxysporum. Sampling at different growth stages showed that F. graminearum was the predominant causal agent of crown and root at the heading stage, whereas other species of Fusarium were mostly observed at the seedling and tillering stages. Moreover, identification of pathogenic species was confirmed using species-specific primers pairs. In F. graminearum isolates, presence of Tri13 gene, responsible for nivalenol (NIV) and deoxynivalenol (DON) mycotoxins biosynthesis, was detected using specific PCR primers. Finally, the ability of trichothecene production of five F. graminearum isolates was confirmed with high-performance liquid chromatography. 相似文献
22.
Thirty-eight genera and 81 species of fungi were isolated and identified from 120 samples of 24 kinds of spices collected from different places at Assiut Governorate, Egypt. Predominant genera wereAspergillus (25 species) andPenicillium (7 species) of whichA. flavus, A. niger, A. ochraceus, A. fumigatus, A. flavus var.columnaris, A. terreus, P. chrysogenum andP. corylophilum were the most commonly occurring. 相似文献
23.
Ansari-Lari M Saadat M Hadi N 《Biochemical and biophysical research communications》2003,312(2):299-302
Workers in the petroleum distribution trades experience relatively low-level exposures to gasoline vapors whose consequences have not been fully elucidated. The purpose of this study was to investigate changes in the hematological parameters among filling station workers who were occupationally exposed to gasoline. The target group for the study consisted of 41 workers from eight filling stations of Shiraz (south of Iran). The control group consisted of 27 healthy subjects matched for age and sex from general population. The complete blood count analysis was done in one laboratory. Using PCR-based method, the genotypes of glutathione S-transferase T1 (GSTT1) and M1 (GSTM1) were determined. Workers were divided into three exposure groups according to employment history: duration less than 1 year, 1-5 years, and more than 5 years. Comparison was performed using Kruskal-Wallis test. In the individuals with the presence of both GSTT1 and GSTM1 functional alleles, comparison between four exposure groups revealed no significant difference for studied hematological variables. There were statistically significant differences between study groups, with only one functional allele, either GSTT1 or GSTM1, for relative number of lymphocytes (chi(2)=9.147, df=3, P=0.027) and neutrophils (chi(2)=9.951, df=3, and P=0.019), and absolute number of lymphocytes (chi(2)=9.135, df=3, and P=0.028), and RBC (chi(2)=10.586, df=3, and P=0.014). These findings could indicate the possible protective effect of concurrent presence of GSTM1 and GSTT1 enzymes on the hematopoietic system of filling station workers. 相似文献
24.
Saad AA O'Connor PJ Mostafa MH Metwalli NE Cooper DP Povey AC Margison GP 《The International journal of biological markers》2005,20(1):69-72
Previous studies suggest that bladder cancer risk may vary with GST genotype but these results are inconsistent. The aim of this study was to explore whether GSTM1, GSTT1 and GSTP polymorphisms were associated with increased bladder cancer risk in an Egyptian population. GSTM1, GSTT1 and GSTP1 genotype frequencies were determined in bladder cancer cases (n=72) and healthy controls with no history of malignancies (n=82) using PCR-based techniques. The GSTT1*2 genotype was particularly associated with increased risk (OR 2.71, 95%CI 1.27-5.73) and the GSTM1*2 genotype to a lesser extent (OR 1.63, 95%CI 0.85-3.10). 18.1% of cases but only 7.3% of controls were GSTP1*B*B homozygotes (OR 2.38, 95%CI 0.83-6.87). The presence of two or more a priori at-risk genotypes was associated with increased bladder cancer risk (OR 2.42; 95%CI 1.47-3.97). These results suggest that polymorphisms in the GST genes are associated with increased risk of bladder cancer among Egyptians. 相似文献
25.
Abu Hena Mostafa Kamal Ki-Hyun Kim Kwang-Hyun Shin Hyung-Seok Seo Hisashi Tsujimoto Hwa-Young Heo Jong-Soon Choi Chul-Soo Park Sun-Hee Woo 《Journal of Plant Biology》2009,52(6):533-542
Glutenin is a major determinant of baking performance and viscoelasticity, which are responsible for high-quality bread with
a light porous crumb structure of a well-leavened loaf. We analyzed the diversity of glutenin genes from six wheat cultivars
(Korean cvs. Keumgang and Jinpum, Chinese cvs. China-108 and Yeonnon-78, and Japanese cvs. Norin-61 and Kantou-107). Glutenins
contain two types of isoforms such as high molecular weight glutenin subunit (HMW-GS) and low molecular weight glutenin subunit
(LMW-GS). Glutenin fractions were extracted from wheat endosperm using Osborne solubility method. A total of 217 protein spots
were separated on two-dimensional gel electrophoresis with isoelectric focusing (wide range of pH 3–10). The proteins spots
were subjected to tryptic digestion and identified by matrix assisted laser desorption/ionization–time of flight mass spectrometry.
HMW-GS (43 isoforms) and LMW-GS (seven isoforms) are directly responsible for producing high-quality bread and noodles. Likewise,
all the seed storage proteins are digested to provide nutrients for the embryo during seed germination and seedling growth.
We identified the diverse glutenin subunits in wheat cultivars and compared the gluten isoforms among different wheat cultivars
according to quality. This work gives an insight on the quality improvement in wheat crop. 相似文献
26.
Mahdavinia M Bishehsari F Verginelli F Cumashi A Lattanzio R Sotoudeh M Ansari R Semeraro D Hormazdi M Fakheri H Rakhshani N De Lellis L Curia MC Cama A Piantelli M Malekzadeh R Iacobelli S Mariani-Costantini R 《Journal of cellular physiology》2008,216(2):543-550
CRC-associated P53 mutations have not been studied extensively in non-Western countries at relatively low CRC risk. We examined, for the first time, 196 paraffin-embedded CRC cases from Northern Iran for mutations in P53 exons 5-8 using PCR-direct sequencing. P53 status and mutation site/type were correlated with nuclear protein accumulation, clinicopathologic variables and data on K-ras mutations and high-level microsatellite instability (MSI-H). We detected 96 P53 mutations in 87 (44.4%) cases and protein accumulation in 84 cases (42.8%). P53 mutations correlated directly with stage and inversely with MSI-H. Distal CRCs were more frequently mutated at major CpG hotspot codons [248 (8/66, 12.1%), 175 (7/66, 10.6%), and 245 (7/66, 10.6%)], while in proximal tumors codon 213, emerged as most frequently mutated (5/28, 17.9% vs. 3/66, 4.5%, P = 0.048). Transitions at CpGs, the most common mutation type, were more frequent in non-mucinous (25% vs. 10.4% in mucinous, P = 0.032), and distal CRC (27% vs. 12.5% in proximal, P = 0.02), and correlated with K-ras transversions. Transitions at non-CpGs, second most common P53 mutation, were more frequent in proximal tumors (15.6% vs. 4.7% in distal, P = 0.01), and correlated with K-ras transitions and MSI-H. Overall frequency and types of mutations and correlations with P53 accumulation, stage and MSI-H were as reported for non-Iranian patients. However P53 mutation site/type and correlations between P53 and K-ras mutation types differed between proximal and distal CRC. The codon 213 P53 mutation that recurred in proximal CRC was previously reported as frequent in esophageal cancer from Northern Iran. 相似文献
27.
Meamar AR Guyot K Certad G Dei-Cas E Mohraz M Mohebali M Mohammad K Mehbod AA Rezaie S Rezaian M 《Applied and environmental microbiology》2007,73(3):1033-1035
Isolates of Cryptosporidium spp. from human and animal hosts in Iran were characterized on the basis of both the 18S rRNA gene and the Laxer locus. Three Cryptosporidium species, C. hominis, C. parvum, and C. meleagridis, were recognized, and zoonotically transmitted C. parvum was the predominant species found in humans. 相似文献
28.
29.
Zahra Rahmani Chang‐Jun Kim Mostafa Ghafouri Moghaddam Ehsan Rakhshani 《Entomological Research》2019,49(9):409-415
Occurrence of the family Ismaridae Thomson is recorded for the first time from Iran, represented by a single species, Ismarus rugulosus Förster, 1850. A series of diagnostic characters and morphometric ratios for this species is presented, as well as a distribution map throughout the Holarctic region. 相似文献
30.
The genes involved in DNA repair system play a crucial role in the protection against mutations. It has been hypothesized
that functional deficiencies in highly conserved DNA repair processes resulting from polymorphic variation may increase genetic
susceptibility to breast cancer (BC). The aim of the present study was to evaluate the association of genetic polymorphisms
in 2 DNA repair genes, XPD (Asp312Asn) and XRCC1 (A399G), with BC susceptibility. We further investigated the potential combined
effect of these DNA repair variants on BC risk. Both XPD (xeroderma pigmentosum group D) and XRCC1 (X-ray repair cross-complementing
group 1) polymorphisms were characterized in 100 BC Egyptian females and 100 healthy women who had no history of any malignancy
by amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) method and PCR with confronting two-pair
primers (PCR-CTPP), using DNA from peripheral blood in a case control study. Our results revealed that the frequencies of
AA genotype of XPD codon 312 polymorphism were significantly higher in the BC patients than in the normal individuals (P ≤ 0.003), and did not observe any association between the XRCC1 Arg399Gln polymorphism and risk of developing BC. Also, no
association between both XPD Asp312Asn and XRCC1 A399G polymorphisms and the clinical characteristics of disease. Finally,
the combination of AA(XPD) + AG(XRCC1) were significantly associated with BC risk. Our results suggested that, XPD gene is
an important candidate gene for susceptibility to BC. Also, gene–gene interaction between XPD(AA) + XRCC1(AG) polymorphism
may be associated with increased risk of BC in Egyptian women. 相似文献