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The complex nature of spinal cord injuries has provided much inspiration for the design of novel biomaterials and scaffolds which are capable of stimulating neural tissue repair strategies. Recently, conductive polymers have gained much attention for improving the nerve regeneration. In our previous study, a three-dimensional (3D) structure with reliable performance was achieved for electrospun scaffolds. The main purpose in the current study is formation of electrical excitable 3D scaffolds by appending polyaniline (PANI) to biocompatible polymers. In this paper, an attempt was made to develop conductive nanofibrous scaffolds, which can simultaneously present both electrical and topographical cues to cells. By using a proper 3D structure, two kinds of conductive scaffolds are compared with a non-conductive scaffold. The 3D nanofibrous core-sheath scaffolds, which are conductive, were prepared with nanorough sheath and aligned core. Two different sheath polymers, including poly(lactic-co-glycolic acid) PLGA and PLGA/PANI, with identical PCL/PANI cores were fabricated. Nanofibers of PCL and PLGA blends with PANI have fiber diameters of 234±60.8 nm and 770±166.6 nm, and conductivity of 3.17×10-5 S/cm and 4.29×10-5 S/cm, respectively. The cell proliferation evaluation of nerve cells on these two conductive scaffolds and previous non-conductive scaffolds (PLGA) indicate that the first conductive scaffold (PCL/ PANI-PLGA) could be more effective for nerve tissue regeneration. Locomotor scores of grafted animals by developed scaffolds showed significant performance of non-conductive 3D scaffolds. Moreover, the animal studies indicated the ability of two new types of conductive scaffolds as spinal cord regeneration candidates.  相似文献   
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Separation of X and Y chromosome-bearing sperm is an appropriate method for the selection of desired sex of offspring to increase the profit in livestock industries. The purpose of this study was the production of a monoclonal antibody against recombinant bovine sex-determining region Y protein for separation Y sperm. The hybridoma cells from splenocytes of immunized female's balb/C mice and Sp2/0 cells were made. The binding affinity of our monoclonal antibody (mAbSRY2) was compared with mouse monoclonal SRY-15. The Western blot method indicated that mAbSRY2 successfully detected the rbSRY protein. The specificity and sensitivity of mAbSRY2 is comparable to SRY-15 commercially ones. The SRY gene in 100% of bull semen contains the Y chromosome that had the strongest binding affinity to mAbSRY2 was synthesized. In other words, the binding affinity of semen contains the X sperms near the negative control. In general, this immunological method can help to separate X from Y sperms. However, the mAbSRY2 is bind to Y-bearing sexed sperm, but in the future; the sexed sperms need to apply in farms.  相似文献   
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BACKGROUND: The amygdala is a forebrain region, which is known as a modulator of pain sensation. The amygdala, particularly the central nucleus, has high concentrations of enkephalins relative to dynorphins and has high concentrations of opioid receptors. We here studied the role of central nuclei of amygdala in morphine antinociception. METHODS: In this study, we used 130 male Wistar rats (200-250 g). Bilateral two guide cannula were inserted into central nuclei of amygdala. The drugs were administrated via intra central-amygdala and intraperitoneal. The antinociceptive effect was measured by formalin test. RESULTS: Bilateral microinjections of morphine (50 and 100 microg/rat) into the central nuclei of amygdala elicited powerful suppression of nociceptive behaviors in both phases of formalin test. The intraperitoneal administration of naloxone (1 and 2 mg/kg) decreased significantly the antinociception induced by the intra-amygdaloid injection of morphine. Our data also showed that microinjection of naloxone (50 and 100 microg/rat) into the central nuclei of amygdala could reduce the analgesic effects of systemic morphine (7 mg/kg). On the other hand, bilateral neurotoxic lesions of the central nuclei of amygdala attenuated the antinociception induced by subcutaneous or intra-amygdaloid injection of morphine. CONCLUSION: These findings suggest that morphine analgesia in the formalin test depends on ascending connections to the forebrain, probably the amygdala.  相似文献   
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Conflicts among forest visitors have direct effects on the quality of a recreational experience. As the number of visitors to forests close to residential areas increases, as well as the number of different activities, so does the potential for perceived conflicts. According to the literature, expanding knowledge of conflict characteristics and their causes is important for recreation planners and managers who aim to reduce conflicts.In the present study, different forest user groups were identified and categorised according to their pursued activities, and for each group, causes of conflict were identified. Furthermore, a choice experiment was constructed to estimate the distance visitors are willing to travel to encounter few visitors as opposed to many visitors, and thereby potentially experience fewer conflicts. Comparing the marginal willingness to travel (WTT) of different user groups suggests that some groups have a WTT further than the average to reach a forest with ‘Few’ visitors. The average WTT to reach a forest area with ‘Few’ visitors. ‘Mountain bikers,’ ‘Peace and nature lovers’ and ‘Horse riders’ are willing to travel 4 km more than the average per visit to reach a less crowded forest. At the other end of the scale, we find that people who are doing physical exercise are willing to travel 2 km less than the average to reach a less crowded forest.  相似文献   
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Salinity is considered as the main factor limiting the yield of crops in arid and semi-arid regions. There are still many uncertainties about the nanotechnology and its potential applications, as well as doubts about its efficacy and safety in the long term. The aim of this study was to examine the alleviative effects of ZnO NPs (nanoparticles) (0, 20 and 80 mgL?1) on toxicity damage caused by NaCl (0, 50 and 100 mM) at physiological and molecular parameters in Rapeseed. Rapeseed plants were treated at the rosette stage by different levels of salinity and ZnO NPs based on a completely randomized design (CRD) with three replications. At the physiological level, salinity stress significantly increased root ion leakage and decreased relative water content (RWC), stomata density and Hill reaction while application of ZnO NPs improved Hill reaction, and reduced ion leakage. At the molecular level, salinity stress significantly reduced the expression of ARP, MYC and SKRD2 genes compared to non-stressed plants while MPK4 gene expression increased under a high level of NaCl imposition. Foliar spraying of ZnO NPs considerably decreased the expression of MYC, MPK4, and SKRD2 genes and increased the expression of the ARP gene. It can be concluded that ZnO NPs had the ability to reduce the toxicity created under salinity stress at the optimal concentration (20 mgL?1) in rapeseed and could play an important role in increasing the resistance of rapeseed plants to salinity stress.  相似文献   
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This study aimed to evaluate the effects of dietary supplemental methionine (Met) source and betaine (Bet) replacement for Met on performance and activity of mitochondrial respiratory chain enzymes (MRCEs) in normal and heat‐stressed broiler chickens. Total of 1,200‐day‐old Ross 308 chicks were allocated to two houses, each consisted of 12 treatments, five replicates of 10 birds each with 2 × 2×3 × 2 (temperature × Met source × Met level × Bet, respectively) split‐plot factorial arrangement. Met level in the basal diets was 70% requirements (Req) that was increased to the requirement or 130% by supplemental dl ‐ or l ‐Met. Bet was or was not substituted at the rate of 30% supplemental dl ‐ or l ‐Met. Feed conversion ratio (FCR) in chicks fed 70% l ‐Met was lower than those fed 70% dl ‐Met diet during 1–10 days (p = 0.04). Broilers fed diets containing requirement or 130% Met, regardless of its source, showed higher weight gain (WG) than those received 70% Met diet during 11–42 days (p < 0.001). Feed intake (FI) of broilers fed 130% Met diet was decreased compared to other two groups during 11–42 days (p < 0.05). One hundred thirty percent Met requirement diet resulted in lower FCR comparing to other two groups during 11–42 days (p < 0.001). Heat‐stressed birds grew less than those under normal condition (p < 0.05). Broilers fed Req Met diet under normal temperature exhibited higher activities of complexes (Cox) I and III (p < 0.05). Cox I activity in heat‐stressed birds fed Bet + diet was similar to those fed Bet‐diet under normal temperature (p = 0.046). It is concluded that performance and the activities of Cox I and III were increased as the level of Met increased. Bet replacement for 30% supplemental Met resulted in similar consequences comparing to non‐Bet replacement diets on performance, but increased the activity of Cox III. l ‐Met was effective than dl ‐Met at the cellular level. High ambient temperature depressed performance and MRCE activity.  相似文献   
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Background: Pseudomonas aeruginosa is one of the opportunistic pathogens causing frequent hospital-acquired life-threatening infections in mechanically ventilated patients. The most significant virulence factor of P. aeruginosa is T3SS. PcrV is an important structural protein of the T3SS. Methods:In the current investigation, a recombinant scFv mAb against the PcrV protein was expressed in EnBase® (fed-batch) cultivation mode. The pETiteTM N-His SUMO Kan vector, including anti-PcrV scFv gene, was transformed into Escherichia coli (BL21) cells. The expression and solubility of anti-PcrV scFv protein were investigated at two different temperatures (25 °C and 30 °C) and at different induction times (4, 6, 8, 12, and 24 hours). Results:Increased efficiency was achieved by EnBase® compared to LB broth; owing to the slow release of glucose, the maximum level of solubility and total protein expression was observed in EnBase® cultivation system at 30 °C and 24 h post induction. Furthermore, IC50 for anti-PcrV scFv protein was determined to be approximately 7 μg/mL. Conclusion:Anti-PcrV scFv produced in this study showed promising in vitro results, protecting RBC from lysis by P. aeruginosa (exoU+). Key Words: Fed Batch, recombinant protein, Pseudomonas aeruginosa, scFv  相似文献   
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Conversion of forest land to farmland in the Hyrcanian forest of northern Iran increases the nutrient input, especially the phosphorus(P) nutrient, thus impacting the water quality. Modeling the effect of forest loss on surface water quality provides valuable information for forest management. This study predicts the future impacts of forest loss between 2010 and 2040 on P loading in the Tajan River watershed at the sub-watershed level. To understand drivers of the land cover, we used Land Change Modeler(LCM) combining with the Soil Water Assessment Tool(SWAT) model to simulate the impacts of land use change on P loading. We characterized priority management areas for locating comprehensive and cost-effective management practices at the sub-watershed level. Results show that agricultural expansion has led to an intense deforestation. During the future period 2010–2040, forest area is expected to decrease by 34,739 hm~2. And the areas of pasture and agriculture are expected to increase by 7668 and 27,071 hm~2, respectively. In most sub-watersheds, P pollution will be intensified with the increase in deforestation by the year 2040. And the P concentration is expected to increase from 0.08 to 2.30 mg/L in all of sub-watersheds by the year 2040. It should be noted that the phosphorous concentration exceeds the American Public Health Association′s water quality standard of 0.2 mg/L for P in drinking water in both current and future scenarios in the Tajan River watershed. Only 30% of sub-watersheds will comply with the water quality standards by the year 2040. The finding of the present study highlights the importance of conserving forest area to maintain a stable water quality.  相似文献   
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