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71.
Acetylcholine (ACh), the classical neurotransmitter, also affects a variety of nonexcitable cells, such as endothelia, microglia, astrocytes and lymphocytes in both the nervous system and secondary lymphoid organs. Most of these cells are very distant from cholinergic synapses. The action of ACh on these distant cells is unlikely to occur through diffusion, given that ACh is very short-lived in the presence of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), two extremely efficient ACh-degrading enzymes abundantly present in extracellular fluids. In this study, we show compelling evidence for presence of a high concentration and activity of the ACh-synthesizing enzyme, choline-acetyltransferase (ChAT) in human cerebrospinal fluid (CSF) and plasma. We show that ChAT levels are physiologically balanced to the levels of its counteracting enzymes, AChE and BuChE in the human plasma and CSF. Equilibrium analyses show that soluble ChAT maintains a steady-state ACh level in the presence of physiological levels of fully active ACh-degrading enzymes. We show that ChAT is secreted by cultured human-brain astrocytes, and that activated spleen lymphocytes release ChAT itself rather than ACh. We further report differential CSF levels of ChAT in relation to Alzheimer’s disease risk genotypes, as well as in patients with multiple sclerosis, a chronic neuroinflammatory disease, compared to controls. Interestingly, soluble CSF ChAT levels show strong correlation with soluble complement factor levels, supporting a role in inflammatory regulation. This study provides a plausible explanation for the long-distance action of ACh through continuous renewal of ACh in extracellular fluids by the soluble ChAT and thereby maintenance of steady-state equilibrium between hydrolysis and synthesis of this ubiquitous cholinergic signal substance in the brain and peripheral compartments. These findings may have important implications for the role of cholinergic signaling in states of inflammation in general and in neurodegenerative disease, such as Alzheimer’s disease and multiple sclerosis in particular.  相似文献   
72.
Drought is the major constraint to chickpea productivity worldwide. Utilizing early flowering genotypes and larger seed size have been suggested as strategies for breeding in drought zones. Therefore, this study aimed to identify potential markers linked to days-to-flowering, 100-seed weight, and plant height in a chickpea intraspecific F2:3 population derived from the cross ILC3279 × ICCV2. A closely linked marker (TA117) on linkage group LG3 was identified for the days-to-flowering trait, explaining 33% of the variation. In relation to plant height, a quantitative trait loci (QTL) was located in LG3, close to the Ts5 marker, that explained 29% of phenotypic variation. A QTL for 100-seed weight located in LG4, close to TA176, explained 51% of variation. The identification of a locus linked both to high 100-seed weight and days-to-flowering may account for the correlation observed between these traits in this and other breeding attempts.  相似文献   
73.
Extant felids show a high degree of inter-sexual dimorphism, meaning significant size differences between males and females. Such a differentiation may have various ecological, behavioural and evolutionary implications, at both species and subspecies levels. We have investigated the sexual size differences in one of the most dimorphic felids, i.e. the Leopard (Panthera pardus), based on 63 craniometric and 55 morphometric samples from Iran which belong to the subspecies Persian Leopard (P. p. saxicolor). In order to explore patterns of sexual dimorphism, multivariate statistical analysis on 24 skull variables as well as univariate approaches for two body measurements were applied. We found significant inter-sexual differences in skull size whereas it was not meaningful after removing the effect of size to address skull shape. Moreover, inter-sexual differentiation was also remarkable when comparing morphometric body measurements in adults, showing that the males possess a larger head mass and longer body, but sub-adults did not show any remarkable differentiation between sexes. A combination of craniometric and morphological features is proposed for sex differentiation in Leopards.  相似文献   
74.
Morphological traits and three molecular markers techniques: start codon targeted (SCoT), inter-simple sequence repeat (ISSR) and directly amplified minisatellite DNA (DAMD) markers were compared for fingerprinting of 40 landraces chickpea genotypes collected from different geographical locations of north-west of Iran. Variance analysis of ten measured morphological traits showed significant differences existed between genotypes. Cluster analysis based on morphological traits, divided genotypes in three distinct clusters. Average polymorphism information content (PIC) for ISSR, DAMD and SCoT markers was 0.216, 0.232 and 0.232, respectively, and this revealed that SCoT markers were more informative, followed by ISSRs marker, than other markers for the assessment of diversity amongst genotypes. Cluster analysis for three different molecular types revealed that genotypes taken for the analysis can be divided in three and four distinct clusters. Accessions from same geographical regions mostly showed more genetic similarities than those from origins far isolated apart. These results suggest that efficiency of SCOT, DAMD and ISSR markers was relatively the same in fingerprinting of genotypes but SCOT and DAMD analysis are more effective in fingerprinting of chickpea genotypes. To our knowledge, this is the first detailed report of a comparison of performance among two targeted DNA region molecular markers (SCoT and DAMD) and the ISSR technique on a set of samples of chickpea. Overall, our results indicate that SCOT, ISSR and DAMD fingerprinting could be used to detect polymorphism for genotypes of chickpea.  相似文献   
75.
Bacillus sp. JER02 is a bacterial strain that can be grown in a medium containing organic solvents and produce a protease enzyme. JER02 protease was purified with a yield of 31.9% of total protein and 328.83-fold purification. K m and Vmax of this protease were established as 0.826 µM and 7.18 µmol/min, respectively. JER02 protease stability was stimulated about 80% by cyclohexane. It exhibited optimum temperature activity at 70°C. Furthermore, this enzyme was active in a wide range of pH (4-12) and showed maximum activity at pH 9.0. The nonionic detergents Tween-20 and Triton X-100 improved the protease activity by 30 and 20%, respectively. In addition, this enzyme was shown to be very stable in the presence of strong anionic surfactants and oxidizing agents, since it retained 77%, 93%, and 98% of its initial activity, after 1 hr of incubation at room temperature with sodium dodecyl sulfate (SDS), sodium perborate (1%, v/v) and H2O2 (1%, v/v), respectively. Overall, the unique properties of the Bacillus sp. JER02 protease suggested that this thermo- and detergent-stable, solvent-tolerant protease has great potential for industrial applications.  相似文献   
76.
Biological control agents can be used as a complementary control measure that can be combined with resistant host plants to control pests. In this study, the effects of different canola cultivars (Karaj-1, Karaj-2, Karaj-3, Licord, Okapi, Opera, RGS003, Sarigol, Talaye and Zarfam) on the performance and life table parameters of the cabbage aphid, Brevicoryne brassicae, and its parasitoid, Diaeretiella rapae, were determined under laboratory conditions. Total fecundity of the cabbage aphid differed with cultivar, with the highest value (59.41 nymphs per female) of this parameter observed on Opera and the lowest (1.67) observed on RGS003. The highest and lowest intrinsic rates of increase (r) of the cabbage aphid were observed on Opera (0.331 day?1) and RGS003 (? 0.242 day?1) cultivars, respectively, suggesting these to be the most susceptible and most resistant cultivars to this pest. However, because the aphid did not settle and feed well on RGS003, it was not possible to determine demographic parameters for its parasitoid. Consequently, the Okapi cultivar, which was the most resistant cultivar to the cabbage aphid after RGS003, was used in this study to assess the parasitoid wasp. The parasitoid’s intrinsic rate of increase (r) varied from 0.426 day?1 on the susceptible cultivar (Opera) to 0.341 day?1 on the resistant canola cultivar Okapi. Aphid performance decreased 93% on the resistant canola cultivar, while parasitoid performance decreased only 20% on the resistant cultivar compared to more susceptible cultivar.  相似文献   
77.
The study was designed to investigate the effects of frozen storage on the proximate composition and chemical indices of pike (Esox lucius) stored for a period of six months at ?20°C. During storage the moisture, protein and fatty acid contents decreased and the ash, total volatile basic nitrogen (TVB‐N) and peroxide value (PV) content increased significantly (P < 0.05). In the fresh samples the moisture, total protein and total lipid contents were 77.61%, 19.21%, and 2.3% respectively. At the end of the storage time the above‐mentioned parameters were measured as 75.98%, 16.95%, 0.9%, respectively. TVB‐N and PV contents changed from 1.30%, 6.27, 0.18 in fresh samples to 2.21%, 15.12 mg/100 g and 1.73 meq o2 kg?1 after six months frozen storage, respectively. Thirty fatty acids were found in pike fillets, with a higher percentage in fresh fish of polyunsaturated fatty acids (51.14%), saturated fatty acids (22.94%) and mono unsaturated fatty acids (22.61%). The PUFAs decreased to 31.67% at the end of the storage time. Although some changes in quality and nutritional value were observed in the pike fillets during frozen storage, the changes were within the acceptable range.  相似文献   
78.
Nasirinezhad  F.  Hosseini  M.  Karami  Z.  Janzadeh  A.  Yousefifard  M. 《Neurophysiology》2019,51(5):322-331
Neurophysiology - We investigated the effectiveness of intrathecal introduction of GABAA and GABAB receptor agonists in reversing pain modalities in a central model of neuropathic pain. In adult...  相似文献   
79.
Molecular Biology Reports - Brucellosis is a major zoonosis all over the world. MicroRNAs are significant gene expression regulators and could be involved during the infections and also genetic...  相似文献   
80.
Five‐week‐old silver barb, Barbodes gonionotus, fry (initial length = 10 mm) were subjected to different salinities of 0, 3, 6 or 9 ppt for 17 days, to then assess their survival and growth. Whole body histological sections were stained with Periodic‐acid Schiff (PAS). Groups of 15 fish were triplicated in each treatment with an ambient temperature (26–28°C). Results showed that growth and condition factor significantly decreased and increased (p < .05), respectively, with the increased salinities after 17 days. While survival was similar (p > .05), between 0 and 6 ppt (at 98% and 87%, respectively), the decrease was significant at 9 ppt (22%). In addition, the fry at 9 ppt had fewer gill mucous cells as well as reduced PAS positive staining intensity within the liver and intestine. This suggests energy was becoming exhausted, leading to mortalities and lower growth. Silver barb early fry were relatively sensitive to elevated salinity, which was likely due to their young age, but short‐term exposure to 3–6 ppt can be used to decrease potential freshwater diseases in the early nursery culture.  相似文献   
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