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81.
Mian Abdur Rahman Arif Alvina Gul Kazi Awais Rasheed Abdul Aziz Napar Abid Riaz 《Archives Of Phytopathology And Plant Protection》2013,46(12):1479-1487
Stripe or yellow rust caused by Puccinia striiformis f. sp. tritici is a threat to many of the existing cultivars of Pakistan. Many attempts are being made to evolve new varieties resistant to stripe rust to reduce the losses caused by this disease. For this purpose, novel genes are needed to incorporate into the existing cultivars. These genes are found in the wild progenitors of wheat that are D-genome donors to wheat. As a result of extensive research, wheat synthetic hexaploids have been developed. These synthetics have resistances against biotic as well as abiotic stresses including the yellow rust. A group of such synthetics has been identified which seems resistant to this destructive disease. This group was tested under field conditions to identify resistance against stripe rust. The same population was analysed at molecular level to explore the genetic diversity for rust resistance. Genetic diversity among 34 selected synthetic hexaploid wheats was studied by random amplified polymorphic DNA (RAPD) analysis. A set of 12 RAPD primers was applied, and the level of polymorphism was found to be 46.67%. The coefficients in the range of 71–100% were detected by genetic similarity matrix based on Nei and Li's index. These coefficients were used for constructing a dendrogram using unweighted pair group of arithmetic means. Synthetic hexaploid line 34 was found to exhibit maximum genetic distances among the 34 selected lines. The same accession also showed excellent phenotypic characters with above average grain weight. These synthetic hexaploids carrying genetic potential for stripe rust resistance and morphological traits should be useful for improvement of existing wheat cultivars. 相似文献
82.
83.
Khan S Kazi TG Baig JA Afridi HI Kolachi NF 《Biological trace element research》2011,144(1-3):205-216
A new method is reported for the separation of aluminum ions (Al(3+)) from interfering cations in pharmaceutical and biological samples through solid-phase extraction (SPE) using 2-methyl-8-hydroxyquinoline (8-hydroxyquinaldine) on activated silica. While separated Al(3+) was preconcentrated by cloud point extraction (CPE) using 3,5,7,2'-4'-pentahydroxyflavone (morin) as complexing reagent, the resulting complex was entrapped in nonionic surfactant (Triton X-114) as prior step to its determination by spectrofluorimetry (SPF). The validity of separation/preconcentration of Al(3+) was checked by certified reference material of human hair and standard addition method. The chemical variables affecting the analytical performance of the separation/preconcentration methods were studied and optimized. The enrichment factor and detection limit of Al(3+) for the preconcentration of 10?ml of dialysate solution and acid-digested samples of scalp hair samples were found to be 25 and 0.34?μg/L, respectively. The relative standard deviation for six replicates of standard containing 20?μg/L of Al(3+) was <10%. In all DS, the concentration of Al was >10?μg/L. The level of Al in scalp hair samples of kidney failure patients was higher than healthy controls. 相似文献
84.
85.
Wadhwa SK Kazi TG Chandio AA Afridi HI Kolachi NF Khan S Kandhro GA Nasreen S Shah AQ Baig JA 《Biological trace element research》2011,144(1-3):86-96
The investigated data shows that arsenic (As) in drinking water is associated with increased mortality from different types of cancers including liver cancer. In this study, blood and scalp hair samples of male liver cancer patients and healthy referents belonging to As exposed areas of Sindh Pakistan were analyzed for As contents. The As levels in drinking water of understudy area showed that sections of this population was exposed to 3-15-folds higher concentrations of As than permissible limit. For comparative purposes, blood and scalp hair samples of matched cancerous patient as referent patients belonging to big city (Hyderabad) who have used municipal treated water with low As levels <10?μg/L were also collected. The results of this study showed that the average As concentration was higher in the blood and scalp hair of exposed and non-exposed referent cancer patients as compared to referents (p?001). The exposed cancerous patients have twofolds higher As level in both biological samples as related to non-exposed case matched cancerous male subjects. 相似文献
86.
Hassan Imran Afridi Tasneem Gul Kazi Naveed Kazi Ghulam Abbas Kandhro Jameel Ahmed Baig Mohammad Khan Jamali Mohammad Balal Arain Abdul Qadir Shah 《Biological trace element research》2011,139(3):368-268
The pathogenesis of some cardiovascular diseases (CVDs) has been altered with changes in the balance of certain trace and
toxic elements. The aim of the present study was to assess the role of zinc (Zn) and cadmium (Cd) in smoker and nonsmoker
male CVD patients (n = 457) of two age groups (31–45) and (46–60). The both elements were determined in biological samples (scalp hair, blood,
and urine) of CVD patients and healthy referents for comparison purpose. The concentrations of Zn and Cd were measured by
atomic absorption spectrophotometer prior to microwave-assisted acid digestion. It was observed that the mean values of Cd
were significantly higher in the biological samples of smokers CVD as compared to nonsmoker CVD patients, while the level
of Zn was lower in both smoker and nonsmoker patients. The concentrations of Zn in whole blood and scalp hair samples were
lower in CVD patients as compared to referents (p > 0.001). Results showed significant changes of levels of Cd and Zn in blood and scalp hair samples of CVD patients when
compared with healthy referents, while reverse in the case of urine samples. It was observed that low Zn levels were associated
with both smoker and nonsmoker CVD patients, while increased cadmium accumulation was observed in smoker patients as compared
to nonsmoker patients (p > 0.025). 相似文献
87.
Rafiq K Sherajee SJ Fan YY Fujisawa Y Takahashi Y Matsuura J Hase N Urata H Nakano D Hitomi H Nishiyama A 《The Chinese journal of physiology》2011,54(1):30-35
A growing body of evidence suggests the potential role of chymase in organ injury in diabetes. We investigated blood glucose levels and survival in transgenic mice carrying the human chymase gene (Tg). Intraperitoneal injections of streptozotocin (STZ) (200, 100, 75 and 50 mg/kg in total, i.p.) were given to uninephrectomized Tg mice and wild-type C57BL/6 (BL) mice. Before STZ injection, the Tg mice had significantly lower body weights and slightly higher systolic blood pressure as compared with the BL mice. STZ-treated Tg mice showed significantly higher postprandial blood glucose levels as compared with the STZ-treated BL mice. The survival prevalence of STZ-treated Tg mice was zero, whereas BL mice showed a value of 40% until 42 days. STZ (100, 75 or 50 mg/kg, i.p.)-treated Tg mice also showed a similar pattern as compared with the STZ-treated BL mice. These data suggest that human chymase contributes to blood glucose levels and mortality during the progression of diabetes. 相似文献
88.
Guiying Cui Kazi S. Rahman Daniel T. Infield Christopher Kuang Chengyu Z. Prince Nael A. McCarty 《The Journal of general physiology》2014,144(2):159-179
The cystic fibrosis (CF) transmembrane conductance regulator (CFTR) bears six extracellular loops (ECL1–6); ECL1 is the site of several mutations associated with CF. Mutation R117H has been reported to reduce current amplitude, whereas D110H, E116K, and R117C/L/P may impair channel stability. We hypothesized that these amino acids might not be directly involved in ion conduction and permeation but may contribute to stabilizing the outer vestibule architecture in CFTR. We used cRNA injected oocytes combined with electrophysiological techniques to test this hypothesis. Mutants bearing cysteine at these sites were not functionally modified by extracellular MTS reagents and were blocked by GlyH-101 similarly to WT-CFTR. These results suggest that these three residues do not contribute directly to permeation in CFTR. In contrast, mutants D110R-, E116R-, and R117A-CFTR exhibited instability of the open state and significantly shortened burst duration compared with WT-CFTR and failed to be locked into the open state by AMP-PNP (adenosine 5′-(β,γ-imido) triphosphate); charge-retaining mutants showed mainly the full open state with comparably longer open burst duration. These interactions suggest that these ECL1 residues might be involved in maintaining the outer pore architecture of CFTR. A CFTR homology model suggested that E116 interacts with R104 in both the closed and open states, D110 interacts with K892 in the fully closed state, and R117 interacts with E1126 in the open state. These interactions were confirmed experimentally. The results suggest that D110, E116, and R117 may contribute to stabilizing the architecture of the outer pore of CFTR by interactions with other charged residues. 相似文献
89.
The present study on carp Catla catla is the first attempt to search for a relationship between the concentrations of melatonin, oxidative status, and oocyte dynamics in the ovary of any fish. We measured the levels of melatonin, different antioxidative agents, and the marker of intracellular stress along with the profiles of different developmental stages of oocyte in the ovary of adult carp during four distinct phases in an annual reproductive cycle. Ovarian melatonin titers displayed significant seasonal variations with a peak during spawning and nadir during post-spawning, and thereby underlined its proximity to the course of ovarian development. A significant positive correlation was found between the ovarian levels of melatonin and the activity of superoxide dismutase (SOD), catalase (CAT), and glutathione transferase (GST), although each of them showed a negative correlation with the level of malondialdehyde (MDA)—a faithful indicator of intracellular stress. However, ovarian melatonin titers did not exhibit any correlation with the levels of reduced glutathione (GSH) and the activity of glutathione peroxidase (GPx). Collectively, our findings suggest that melatonin measured in carp ovary may be associated with an enhanced activity/level of selective antioxidative agents for reduction in oxidative stress to augment ovarian functions during the spawning. 相似文献
90.
Anthony J. Davis Linfeng Chi Sairei So Kyung-Jong Lee Eiichiro Mori Kazi Fattah Jun Yang David J. Chen 《Nucleic acids research》2014,42(18):11487-11501
Non-homologous end-joining (NHEJ) and homologous recombination (HR) are the two prominent pathways responsible for the repair of DNA double-strand breaks (DSBs). NHEJ is not restricted to a cell-cycle stage, whereas HR is active primarily in the S/G2 phases suggesting there are cell cycle-specific mechanisms that play a role in the choice between NHEJ and HR. Here we show NHEJ is attenuated in S phase via modulation of the autophosphorylation status of the NHEJ factor DNA-PKcs at serine 2056 by the pro-HR factor BRCA1. BRCA1 interacts with DNA-PKcs in a cell cycle-regulated manner and this interaction is mediated by the tandem BRCT domain of BRCA1, but surprisingly in a phospho-independent manner. BRCA1 attenuates DNA-PKcs autophosphorylation via directly blocking the ability of DNA-PKcs to autophosphorylate. Subsequently, blocking autophosphorylation of DNA-PKcs at the serine 2056 phosphorylation cluster promotes HR-required DNA end processing and loading of HR factors to DSBs and is a possible mechanism by which BRCA1 promotes HR. 相似文献