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111.
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Azam Sadat Hosseini Alhashemi Abdolreza R. Karbassi Bahram Hassanzadeh Kiabi Seyed Masoud Monavari Seyed Mohammad Bagher Nabavi Mohammad Sadegh Sekhavatjou 《Biological trace element research》2011,142(3):500-516
Present study investigates relationships between total and bioaccessibility of trace elements (Cd, Co, Cr, Cu, Mn, NI, Pb,
V, and Zn) concentrations in sediment and their bioaccumulation in species in Shadegan wetland in southwest of Iran. Bioavailability
factor (BAF) and translocation factor (TF) were calculated in plants and trophic transfer factor (TTF) was determined in bird
species. For this purpose, sampling of sediments, aquatic plants including Phragmites australis, Typha australis, Scripus maritimus and two bird species encircling Porphyrio porphyrio and globally threatened Marmaronetta angustirostris were carried out during winter 2009. Result of chemical analysis show that bioaccessibility concentrations of Mn (8.31 mg/kg),
V (1.33 mg/kg), and Pb (1.03 mg/kg) are higher than other metals. The uptake trend of trace elements in plant decreases as
root > stem > leaf. Accumulation levels of trace elements in different tissues of P. porphyrio and M. angustirostris are almost identical and considerable. Accumulation and toxicity of Cd in birds is more than plants. In addition, BAF of
V, Pb, and Cr indicates high accumulation by plants and great pollution rate in the area of study. In S. maritimus TF for Mn, Cu, Pb, and V are high whereas in T. australis, Cu and Pb posses the highest TF. Also Cr, Co, Mn, Ni, and Zn have higher TF from stem to leaf than root to stem in P. australis. Finally, TTFs were compared in various bird species. 相似文献
113.
Tohidi M Ghasemi A Hadaegh F Arbabi S Hosseini Isfahani F 《Biological trace element research》2011,143(2):835-843
This study aims at determining the association between markers of hepatic injury and serum, urinary, and intra-erythrocyte
magnesium concentrations and dietary magnesium intake in obese children and adolescents. In a case–control study, 42 obese
children and adolescents (8–18 years) and 42 sex- and puberty-matched controls were studied. Serum, urinary, and intra-erythrocyte
magnesium levels, indices of insulin sensitivity, and liver enzymes were measured. Dietary magnesium intake was assessed using
a food frequency questionnaire. Obese children and adolescents exhibited insulin resistance as determined by a higher fasting
insulin and the HOMA-IR (p < 0.001) and lower QUICKI indices (p = 0.001); in addition these subjects had significantly higher intra-erythrocyte magnesium (IEM) concentrations, than non-obese
ones (3.99 ± 1.05 vs. 3.35 ± 1.26 mg/dL of packed cell; p = 0.015). Among liver enzymes, only gamma-glutamyl transferase (GGT) was significantly higher in obese than in non-obese
subjects (22.7 ± 9.4 vs. 17.1 ± 7.9 U/l; p = 0.002). A positive association was found between GGT and IEM in both groups; however in multivariate analysis, in obese
subjects, only GGT (p = 0.026) and, in non-obese subjects, only age (p = 0.006) remained as significant predictors of IEM. In conclusion, increased IEM concentration was seen in insulin-resistant
obese children and adolescents; furthermore, serum GGT was associated with IEM, independently of body mass index and HOMA-IR. 相似文献
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Hassan Etesami Hossein Mirseyed Hosseini Hossein Ali Alikhani 《Physiology and Molecular Biology of Plants》2014,20(4):425-434
This study was conducted to investigate the role of 1-aminocyclopropane-1-carboxylate (ACC) deaminase in Pseudomonas fluorescens strain REN1 and its ability to reduce ethylene levels produced during stress, endophytically colonize and promote the elongation of the roots of rice seedlings under gnotobiotic conditions. We isolated 80 bacteria from inside roots of rice plants grown in the farmers’ fields in Guilan, Iran. All of the isolates were characterized for plant growth promoting (PGP) traits. In addition, the colonization assay of these isolates on rice seedlings was carried out to screen for competent endophytes. The best bacterial isolate, based on ACC deaminase production, was identified and used for further study. 16S rDNA sequence analysis revealed that the endophyte was closely related to Pseudomonas fluorescens. The results of this study showed ACC deaminase containing P. fluorescens REN1 increased in vitro root elongation and endophytically colonized the root of rice seedlings significantly, as compared to control under constant flooded conditions. The trait of low amount of indole-3-acetic acid (IAA) production (<15 μg mL−1) and the high production of ACC deaminase by bacteria may be main factors in colonizing rice seedling roots compared to other PGP traits (siderophore production and phosphate solubilization) in this study. Endophytic IAA and ACC deaminase-producing bacteria may be preferential selections by rice seedlings. Therefore, it may be suggested that the utilization of ACC as a nutrient gives the isolates advantages in more endophytic colonization and increase of root length of rice seedlings. 相似文献
117.
Mir-Jamal Hosseini Fatemeh Shaki Mahmoud Ghazi-Khansari Jalal Pourahmad 《Cell biochemistry and biophysics》2014,70(1):367-381
Oxidative damage has been implicated in disorders associated with abnormal copper metabolism and also Cu2+ overloading states. Besides, mitochondria are one of the most important targets for Cu2+, an essential redox transition metal, induced hepatotoxicity. In this study, we aimed to investigate the mitochondrial toxicity mechanisms on isolated rat liver mitochondria. Rat liver mitochondria in both in vivo and in vitro experiments were obtained by differential ultracentrifugation and the isolated liver mitochondria were then incubated with different concentrations of Cu2+. Our results showed that Cu2+ induced a concentration and time-dependent rise in mitochondrial ROS formation, lipid peroxidation, and mitochondrial membrane potential collapse before mitochondrial swelling ensued. Increased disturbance in oxidative phosphorylation was also shown by decreased ATP concentration and decreased ATP/ADP ratio in Cu2+-treated isolated mitochondria. In addition, collapse of mitochondrial membrane potential (MMP), mitochondrial swelling, and release of cytochrome c following of Cu2+ treatment were well inhibited by pretreatment of mitochondria with CsA and BHT. Our results showed that Cu2+ could interact with respiratory complexes (I, II, and IV). This suggests that Cu2+-induced liver toxicity is the result of metal’s disruptive effect on liver hepatocyte mitochondrial respiratory chain that is the obvious cause of Cu2+-induced ROS formation, lipid peroxidation, mitochondrial membrane potential decline, and cytochrome c expulsion which start cell death signaling. 相似文献
118.
Motahare-Sadat Hosseini Ali Asghar Katbab 《Reports of Biochemistry & Molecular Biology》2014,3(1):20-28
Background:
One area of nanoscience deals with nanoscopic interactions between nanostructured materials and biological systems. To elucidate the effects of the substrate surface morphology and viscoelasticity on cell proliferation, fractal analysis was performed on endothelial cells cultured on nanocomposite samples based on silicone rubber (SR) and various concentrations of organomodified nanoclay (OC).Methods:
The nanoclay/SR ratio was tailored to enhance cell behavior via changes in sample substrate surface roughness and viscoelasticity.Results:
Surface roughness of the cured SR filled with negatively-charged nanosilicate layers had a greater effect than elasticity on cell growth. The surface roughness of SR nanocomposite samples increased with increasing the OC content, leading to enhanced cell growth and extracellular matrix (ECM) remodeling. This was consistent with the decrease in SR segmental motions and damping factor as the primary viscoelastic parameters by the nanosilicate layers with increasing clay concentrations.Conclusions:
The inclusion of clay nanolayers affected the growth and behavior of endothelial cells on microtextured SR.Key Words: Silicone rubber, Nanoclay, Elastic Modulus, Roughness, Cell proliferation 相似文献119.
H. Raeisi M. Daliri A. Hosseini E. Kamrani G. H. Moradinasab M. Aghajanpour M. Moein M. Naderi 《Zeitschrift fur angewandte Ichthyologie》2014,30(5):1071-1072
Length–weight relationships (LWRs) for four little‐known fish species collected in the northern Persian Gulf (south of Iran) are presented, namely, Leiognathus lineolatus, Grammoplites suppositus, Eupleurogrammus muticus and Acanthocepola abbreviate. Thus far, these are the first LWRs for these species in the international scientific literature. 相似文献
120.