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Malek Zarei Masoumeh Sabetkasaei Taraneh Moini Zanjani 《Iranian Biomedical Journal》2014,18(2):94-100
Background: P2X4 receptor (P2X4R), a purinoceptor expressed in activated spinal microglia, plays a key role in the pathogenesis of neuropathic pain. Spinal nerve injury induces up-regulation of P2X4R on activated microglia in the spinal cord, and blockade of this receptor can reduce neuropathic pain. The present study was undertaken to determine whether paroxetine, an inhibitor of P2X4R, could attenuate allodynia and hyperalgesia in chronic constriction injury (CCI) model of neuropathic pain when used preemptively or after the sciatic nerve injury. Methods: Male Wistar rats (150-200 g, n = 6) were divided into 3 different groups: 1- CCI vehicle-treated group, 2- Sham group, and 3- CCI paroxetine-treated group. Paroxetine (10 mg/kg, i.p.) was administered 1 h before surgery and continued daily until day 14. In other part of the study, paroxetine (10 mg/kg, i.p.) was administered at day 7 post injury and continued daily until day 14. von Frey filaments for mechanical allodynia and analgesia meter for thermal hyperalgesia were used to assay pain behavior. Results: In a preventive paradigm, paroxetine significantly attenuated both mechanical allodynia and thermal hyperalgesia (P<0.001). A significant decrease in pain behavior was seen with paroxetine on existing allodynia (P<0.001) and hyperalgesia (P<0.01) when initiated at day 7 post injury. Conclusion: It seems that paroxetine can attenuate pain behavior when administered before and also after sciatic nerve injury in CCI model of neuropathic pain. Key Words: Paroxetine, P2X4 receptor (P2X4R), Allodynia, Hyperalgesia 相似文献
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Background: Infectious by Pseudomonas aeruginosa has spread worldwide and metallo-beta-lactamases (MBL) are being reported with increasing frequency. The aim of this study was to investigate the antibiotic susceptibility and distribution of blaVIM and blaIMP genes in P. aeruginosa isolates from Zanjan Province of Iran. Methods: A total of 70 P.
aeruginosa isolates were identified from patients admitted at intensive care units. The antimicrobial susceptibility was tested by disk diffusion (Kirby-Bauer) method and for production of MBL using double-disk synergy test (DDST). After DNA extraction, the presence of blaVIM and blaIMP genes and class 1 integron were detected by PCR. RESULTS: Most of the isolates were resistant to meropenem, cefotaxime and imipenem (IPM). Also, 44/70 (62.85%) IPM resistant isolates were confirmed by DDST. Of the 44 clinical isolates, 41 (93%) isolates showed MIC≥4 µg/ml for IPM. Based on the DDST results, 36 (87.8%) were confirmed to be MBL producers. PCR amplification showed that 23/41 (56%) carried blaVIM and 10/41 (24.3%) possessed blaIMP gene. Also, 31/44 (70.5%) isolates contained class 1 integron gene. Conclusion: Our results highlight that the genes for Verona integron-encoded metallo-β-lactamase, IPM β-lactamases and class 1 integrons were predominantly present among the IPM-resistant P. aeruginosa tested in our province and also the frequency of blaVIM type is higher than blaIMP. This is the first report of P. aeruginosa strains producing blaIMP with high frequency from Zanjan province of Iran. Key Words: Pseudomonas aeruginosa, Beta-lactamases, PCR 相似文献
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Forests are among the most important carbon sinks on earth. However, their complex structure and vast areas preclude accurate estimation of forest carbon stocks. Data sets from forest monitoring using advanced satellite imagery are now used in international policy agreements. Data sets enable tracking of emissions of CO2 into the atmosphere caused by deforestation and other types of land-use changes. The aim of this study is to determine the capability of SPOT-HRG Satellite data to estimate aboveground carbon stock in a district of Darabkola research and training forest, Iran. Preprocessing to eliminate or reduce geometric error and atmospheric error were performed on the images. Using cluster sampling, 165 sample plots were taken. Of 165 plots, 81 were in natural habitats, and 84 were in forest plantations. Following the collection of ground data, biomass and carbon stocks were quantified for the sample plots on a per hectare basis. Nonparametric regression models such as support vector regression were used for modeling purposes with different kernels including linear, sigmoid, polynomial, and radial basis function. The results showed that a third-degree polynomial was the best model for the entire studied areas having an root mean square error, bias and accuracy, respectively, of 38.41, 5.31, and 62.2; 42.77, 16.58, and 57.3% for the best polynomial for natural forest; and 44.71, 2.31, and 64.3% for afforestation. Overall, these results indicate that SPOT-HRG satellite data and support vector machines are useful for estimating aboveground carbon stock. 相似文献
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In order to determine the chelating effect of activated charcoal, a total of 150 beluga (270 g) were fed for 60 days with a diet containing 0 (control), 5, 10, 15 and 20 g activated charcoal per kg. Afterwards, the fish were subjected to challenging with 1 mg/L of each of heavy metals including lead, cadmium and copper during seven days. As results, the highest percentage of body weight gain, specific growth rate, condition factor, protein efficiency ratio and the lowest feed conversion ratio before and after challenging with heavy metals were obtained in 15 g treatment with significant differences comparing to other treatment (p < .05). In all treatments, considerable differences were observed between two experimental stages of all parameters except condition factor and feed conversion ratio (p < .05). No mortalities were observed during the experiment. Before challenging with heavy metals, 15 g treatment showed the lowest activities of AST and ALT enzymes, and uric acid, protein, albumin and cholesterol amounts. The minimum amounts of creatinine and glucose were recorded in the control and 20 g treatments respectively. The highest levels of these parameters, except for creatinine and uric acid, were measured in the control group. After challenging with heavy metals, the lowest levels of AST and ALT enzyme activities, uric acid, creatinine, and glucose, and the highest amounts of protein, albumin and cholesterol belonged to 15 g, whereas the results in the control group were almost opposite. In all treatments, significant differences were observed between two experimental stages of all parameters except AST, uric acid, glucose and cholesterol (p < .05). In the pre‐challenge stage, the maximum amount of carcass protein was observed in 15 g while the differences in lipid content were not significant (p > .05). Moreover, the highest contents of moisture and ash were measured in the control group and 20 g respectively. After the challenge, the highest values of protein and lipid were quantified in 15 g, while the maximum values of ash and moisture were observed in 20 g and control group respectively. Also, significant differences were observed just in ash and moisture amounts in both stages (p < .05). Accumulations of cadmium, copper and lead were maximal in the control group in both stages, and their amount were decreased in sample with 15 g of activated charcoal until they reached to their lowest value in sample with 20 g of activated charcoal. The only different parameter between two treatments was copper amount. Also, significant differences were observed in all treatments in both stages (p < .05). Although activated charcoal at 20 g/kg diet yielded the best results in metal chelation, it is recommended to add 15 g/kg of activated charcoal to the diet of beluga because of other parameters. 相似文献
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Masoumeh Chahartaghi Reinhard Langel Liliane Ruess 《Soil biology & biochemistry》2005,37(9):1718-1725
In soil a high number of species co-exist without extensive niche differentiation, which was assigned as ‘the enigma of soil animal species diversity’. In particular, the detritivores are regarded as food generalists. We have investigated nitrogen stable isotope ratios (15N/14N) of a major decomposer group, the Collembola, to evaluate trophic relationship and determine feeding guilds. Additionally, the δ15N values of potential food sources such as mosses, lichens and other plant derived material (bark, nuts, leaves) were analysed. The natural variation in nitrogen isotopes was assessed in 20 Collembola taxa from three deciduous forest stands. The δ15N signature formed a continuum from phycophages/herbivores to primary and secondary decomposers, reflecting a gradual shift from more detrital to more microbial diets. The δ15N gradient spanned over 9 δ units, which implies a wide range in food sources used. Assuming a shift in 15N of about 3 ‰ per trophic level, the results indicate a range of three trophic levels. These variations in 15N/14N ratios suggest that trophic niches of Collembola species differ and this likely contributes to Collembola species diversity. 相似文献
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Seyyedeh Masoumeh Hasheminia Jalal Jalali Sendi Khalil Talebi JahromiSaeid Moharramipour 《Pesticide biochemistry and physiology》2011,99(3):244-249
The biological effects of two important medicinal plants, Artemisia annua L. and Achillea millefolium (L.) (viz, mortality, growth, and feeding indices as well as enzyme and non-enzymatic activities) were studied on small white Pieris rapae L a deleterious pest of cruciferous plants under controlled conditions (16:8 h L:D at 25 ± 1 °C and 65 ± 5% RH). The LC50 and LC25 values were 9.387% and 3.645% for A. annua L. and 4.19% and 1.69% for A. millefolium (L.), respectively. At the lowest concentration (0.625%), the deterrency was 29.826% and 44.185% for A. annua L. and A. millefolium (L.), respectively. Feeding indices were variously affected with changes in a number of parameters and an increase in larval and pupal duration. The activity level of alkaline phosphatase increased sharply while alanin and aspartate aminotransferases showed a sharp decrease. For non-enzymatic compounds, the amount of glucose and uric acid increased, but total protein and cholesterol decreased. These results indicate that these two medicinal plants might possess potential secondary metabolites that may be useful for controlling potential insect pests. 相似文献
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Distribution and Contamination of Heavy Metal in the Coastal Sediments of Port Klang, Selangor, Malaysia 总被引：1，自引：0，他引：1
Seyedeh Belin Tavakoly Sany Aishah Salleh Majid Rezayi Naghmeh Saadati Leila Narimany Ghazaleh Monazami Tehrani 《Water, air, and soil pollution》2013,224(4):1-18
The coastal sediments of Port Klang in Malaysia were monitored from November 2009 to October 2010 to evaluate the spatial distribution of heavy metals As, Cu, Cd, Cr, Ni, Pb, Zn, Pb, Mn, Al and Fe. Sediment samples were collected from 21 stations, covering three subsidiary ports, namely West Port, North Port and South Port, at three-month intervals. The geo-accumulation index and the enrichment factor were estimated to assess contamination status based on background values. Additionally, the sediment quality guide was applied to evaluate the adverse biological effects of heavy metals. These results show that the concentrations of some metals, such as As, Cd and Pb were comparatively higher than the background values. This is considered a critical environmental issue for this region. Furthermore, the toxicity estimation indicates that living organisms have a high risk of As exposure. Spatial distribution maps of heavy metals would aid in the identification of pollution sources and vulnerable sites. 相似文献