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301.
This study was conducted to investigate heavy metal contamination in agricultural soils and their transfer in a soil-potato system. A total of 59 pairs of potato and soil samples, representing different locations were collected from Hamedan, western Iran and subjected to heavy metals analysis. Average concentrations of Cd, Cu, Fe, Mn, Ni, Pb, and Zn were 1.2, 13.1, 161.4, 13.2, 3.2, 19.5, and 41.5 mg kg?1 dry weight in potato tubers, respectively. A sequence of decreasing plant transfer factors values: Cd > Pb > Cu > Zn > Ni ≥ Mn > Fe was obtained. Furthermore, the health risk index (HRI) values were within the safe limit (<1) except for Cd and Pb. HRI values for Cd and Pb were higher than 1, indicating potential health risk, especially for children. The results indicated that daily intakes of Cd and Pb in potato in the study area may present a future hazard. 相似文献
302.
Many types of researches have been carried out on sandy soils to improve the fertility through bacteria. In this regard, after measuring the activity of urease enzymes in urea bacterial sediments, calcium carbonate was applied in Sirjan soil (southeast of Iran), and the native bacteria of this soil were isolated. The strains of these microorganisms, because of the Come and aridity in the region and the severity of the environmental conditions in the area, have a greater resistance to chemical and physical factors and are compatible with the environment of this region. In this study, we tried to use two types of soil bacteria: one is Sporosaercina pasturii, many researchers have been working on this bacterium and the effects of soil improvement, and another is the native bacterium found in Sirjan soil (Acinetobacter calcoaceticus strain Nima). Thirty samples were taken in the same conditions and experiments to evaluate the use of native bacteria of Sirjan in soil remediation by direct shear testing, seismic electronic microscopy, and microscopic scanning (SEM) were performed on the samples. The treatment period for this study was 28?days. The results showed that the angle of internal friction increased for the treated A. calcoaceticus Nima (42%) and S. paturii (39%) compared to untreated samples. Also, adhesion between particles increased by 14.5 times for A. calcoaceticus Nima and 13.5 times for S. paturii. Finally, shear strength for soil treatment increased by4.6 times for A. calcoaceticus Nima and 3.9 times for S. pasturii. The use of indigenous strains in the natural environment due to the adaptation of strains to environmental conditions can increase the production of bio-cementation. It is, therefore, possible to use native bacteria for biologically improved soil as an appropriate alternative rather than traditional methods due to environmental problems. 相似文献
303.
304.
Hossein Sharifi Alimohammad Shafiee Ghader Molavi Ebrahim Razi Nousin Mousavi Mostafa Sarvizadeh Mohsen Taghizadeh 《Journal of cellular biochemistry》2019,120(10):16307-16315
Leukemia is a cancer, which is derived from leukocytes and precursors of leukocytes in the bone marrow. A large number of pivotal biological processes are linked to leukemia pathogenesis. More insights into these mechanisms can provide a better developing pharmacological platform for patients with leukemia. Among the different players in leukemia pathogenesis, exosomes have appeared as a new biological vehicle, which can transfer oncogenic signals to blood cells. Exosomes are nano-carriers, which enable transferring numerous cargos such as DNA fragments, RNAs, messenger RNAs, microRNAs, long noncoding RNA, and proteins. Targeting the contents of exosomes leads to the alteration of host cell behavior. Increasing evidence has indicated that leukemia-derived exosomes could be utilized as prognostic, diagnostic, and therapeutic biomarkers for individuals suffering from leukemia. In this regard, the importance of exosomes in terms of initiation and progression of leukemia was underlined in this study. 相似文献
305.
The determination of the myocardium’s tissue properties is important in constructing functional finite element (FE) models of the human heart. To obtain accurate properties especially for functional modeling of a heart, tissue properties have to be determined in vivo. At present, there are only few in vivo methods that can be applied to characterize the internal myocardium tissue mechanics. This work introduced and evaluated an FE inverse method to determine the myocardial tissue compressibility. Specifically, it combined an inverse FE method with the experimentally-measured left ventricular (LV) internal cavity pressure and volume versus time curves. Results indicated that the FE inverse method showed good correlation between LV repolarization and the variations in the myocardium tissue bulk modulus K (K = 1/compressibility), as well as provided an ability to describe in vivo human myocardium material behavior. The myocardium bulk modulus can be effectively used as a diagnostic tool of the heart ejection fraction. The model developed is proved to be robust and efficient. It offers a new perspective and means to the study of living-myocardium tissue properties, as it shows the variation of the bulk modulus throughout the cardiac cycle. 相似文献
306.
Elham Shakiba Ali Bazi Hamed Ghasemi Reza Eshaghi-Gorji Seyyed Alireza Mehdipour Banafsheh Nikfar Mohsen Rashidi Sepideh Mirzaei 《Journal of cellular and molecular medicine》2023,27(18):2756-2769
Considering the unfavourable response of breast cancer (BC) to treatment, we assessed the therapeutic potential hesperidin in mice bearing 4T1 BC tumours. Anti-tumour effects were assessed by measuring pathologic complete response (pCR), survival analysis, immunohistochemistry for E-cadherin, VEGF, MMP9, MMP2 and Ki-67, serum measurement of IFNγ and IL-4, and gene expression analysis of CD105, VEGFa, VEGFR2 and COX2. Survival of tumour-bearing mice was the highest in mice receiving a combination of hesperidin and doxorubicin (Dox) (80%) compared to the normal saline (43%), hesperidin 5 (54%), 10 (55.5%), 10 (60.5%) and 40 (66%) mg/kg, and 10 mg/kg Dox-treated (73%) groups (p < 0.0001 for all). Compared to the normal saline group, there was a significant elevation in IFNγ level in the animals receiving 20 (p = 0.0026) and 40 (p < 0.001) mg/kg hesperidin, 10 mg/kg Dox (p < 0.001), and combined hesperidin (20 mg/kg) and Dox (10 mg/kg) (p < 0.001). A significant reduction in the gene expression of CD 105 (p = 0.0106), VEGFa (p < 0.0001), VEGFR2 (p < 0.0001), and Cox2 (p = 0.034) and a significant higher pCR score (p = 0.006) were noticed in mice treated with 10 mg/kg Dox + 20 mg/kg hesperidin compared to those treated with 10 mg/kg Dox alone. Immunohistochemical staining showed significant reductions in Ki-67 (p < 0.001) and VEGF (p < 0.001) and a significant elevation in E-cadherin (p = 0.005) in the 10 mg/kg Dox + 20 mg/kg treatment group than in 10 mg/kg Dox alone group. Hesperidin can be considered as a potentially suitable anti-cancer agent for BC that can synergize with other chemotherapeutics. 相似文献
307.
Khalighi Sikaroudi Masoumeh Sedaghat Meghdad Shidfar Farzad Talebi Sepide Hosseini-Baharanchi Fatemeh Sadat Masoodi Mohsen Farahani Safoura Vasheghani 《Amino acids》2023,55(2):193-202
Amino Acids - The hypertonicity of internal anal sphincter resting pressure is one of the main causes of chronic anal fissure. Therefore, the aim of this study was to assess the effect of oral... 相似文献
308.
Modulation of the platelet thromboxane A2 and aortic prostacyclin synthesis by dietary selenium and vitamin E 总被引:1,自引:0,他引:1
Mohsen Meydani 《Biological trace element research》1992,33(1-3):79-86
Vitamin E and selenium (Se) interact synergistically as an important antioxidant defense mechanism. Se, an essential component
of glutathione peroxidase (GSH-Px) and vitamin E decompose fatty acid hydroperoxides and hydrogen peroxides generated by free
radical reactions. Vitamin E and GSH-Px may modulate arachidonic acid metabolism and the activity of cyclooxygenase enzymes
by affecting peroxide concentration. The balance between arterial wall prostacyclin (PGI2) production and platelet thromboxane (TX)A2 directly influences platelet activity. In order to elucidate the differential role of dietary vitamin E and Se in aortic
PGI2 and platelet TXA2 synthesis, 1-mo-old F344 rats were fed semipurified diets containing different levels of vitamin E (0, 30, 200 ppm) and Se
(0, 0.1, 0.2 ppm) for 2 mo. Thromboxane B2 (TXB2) and 6-keto-PGF1α, were measured by radioimmunoassay (RIA) after incubation of whole blood and aortic rings at 37°C for 10 and 30 min, respectively.
Vitamin E deficiency reduced plasma vitamin E to 5–17% of control-fed rats, and supplementation increased it to 53% of the
control-fed rats. Se supplementation in vitamin E-supplemented animals increased plasma GSH-Px by 17%, compared to vitamin
E-deficient rats. Se and vitamin E supplementation did not have a similar effect on TXB2 and PGI2 synthesis. Se deficiency did not alter platelet TXB2 synthesis, but significantly decreased aortic PGI2 synthesis. It was necessary to supplement with both antioxidants in order to increase, PGI2 synthesis. Se and vitamin E deficient groups had a higher TXB2/PGI2 ratio (0.17±0.08) compared to Se- and vitamin E-supplemented groups (0.03±0.01). These results confirm previous reports in
humans and animals and are in accordance with epidemiological data indicating an inverse relationship between plasma Se and
platelet aggregation. Thus, further suggesting that vitamin E and Se may have a specific role in controlling TXA2 and PGI2 synthesis. 相似文献
309.
Fifteen echocardiographic recordings in nine patients with bacterial endocarditis revealed vegetations in six cases. The vegetations appeared as uneven, irregular thickening of a valve, a mass of shaggy, dense echoes attached to a leaflet or cusp, or a mass of irregular dense echoes in the cavity or outflow tract of the left ventricle. Such findings were seen only on the echocardiograms of very sick patients with severe valvular lesions. Three patients had flail mitral valves. Echocardiography was not helpful in differentiating between active and healed lesions. Problems in the identification and differential diagnosis of vegetations shown on echocardiograms are discussed. 相似文献
310.
Sharifzadeh M Tavasoli M Naghdi N Ghanbari A Amini M Roghani A 《Journal of neurochemistry》2005,95(4):1078-1090
Recently, we demonstrated that intrahippocampal infusion of the cyclo-oxygenase (COX)-2-specific inhibitor celecoxib impaired spatial memory retention in the Morris water maze. In the present work, we investigated the effects of nicotine, infused in the rat dorsal hippocampus several minutes after infusion of celecoxib, on memory retention in the Morris water maze. Rats were trained for 3 days; each day included two blocks, and each block contained four trials. Test trials were conducted 48 h after surgery. As expected, bilateral intrahippocampal infusion of celecoxib (19 microg/side; 0.1 m) increased escape latency and travel distance in rats, indicating significant impairment of spatial memory retention. We also examined the effects of bilateral infusion of nicotine (0.5, 1.0 and 2.0 microg/side) on memory retention. Infusion of 1 microg nicotine significantly decreased escape latency and travel distance but not swimming speed, compared with controls, suggesting memory retention enhancement by nicotine at this concentration. In separate experiments, bilateral infusion of nicotine, infused 5 min after 0.1 m (19 microg/side) celecoxib infusion, was associated with escape latency, travel distance and swimming speed profiles very similar to those in control animals. Brain tissue sections from several of these animals were subjected to immunohistochemical staining analysis with anti-COX-2 antibodies. Quantification analysis by optical density measurements showed that the celecoxib infusion reduced the immunoreactivity of COX-2-containing neurons in the CA1 area of the hippocampus compared with controls, although this reduction was not significant. However, infusion of a combination of celecoxib and nicotine significantly increased this immunoreactivity compared with levels in control and celecoxib-infused groups. These results suggest that nicotine prevented or reversed the adverse effects of celecoxib on spatial memory retention and protected or restored the immunostaining pattern of COX-2 neurons in the rat dorsal hippocampus. 相似文献