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991.
The generally positive relationship between biodiversity of groups of directly or indirectly interacting organisms is one of the most important ecological concepts (Gaston, 2000 Nature, 405 , 220–227; Scherber C, Eisenhauer N, Weisser WW et al., 2010 Nature, 468 , 553–556). In a recent issue of Molecular Ecology, Gao C, Shi N‐N, Liu Y‐X et al. (2013: 22 , 3403–3414) reported that the richness of plants and ectomycorrhizal fungi is positively correlated both at local and at global scales. Here, we challenge these findings by re‐analysis of data and ascribe the reported results to sampling effect and poor data compilation. 相似文献
992.
Fereshteh Pourabdolhossein Sabah Mozafari Ghislaine Morvan-Dubois Javad Mirnajafi-Zadeh Alejandra Lopez-Juarez Jacqueline Pierre-Simons Barbara A. Demeneix Mohammad Javan 《PloS one》2014,9(9)
Background
Inhibitory factors have been implicated in the failure of remyelination in demyelinating diseases. Myelin associated inhibitors act through a common receptor called Nogo receptor (NgR) that plays critical inhibitory roles in CNS plasticity. Here we investigated the effects of abrogating NgR inhibition in a non-immune model of focal demyelination in adult mouse optic chiasm.Methodology/Principal Findings
A focal area of demyelination was induced in adult mouse optic chiasm by microinjection of lysolecithin. To knock down NgR levels, siRNAs against NgR were intracerebroventricularly administered via a permanent cannula over 14 days, Functional changes were monitored by electrophysiological recording of latency of visual evoked potentials (VEPs). Histological analysis was carried out 3, 7 and 14 days post demyelination lesion. To assess the effect of NgR inhibition on precursor cell repopulation, BrdU was administered to the animals prior to the demyelination induction. Inhibition of NgR significantly restored VEPs responses following optic chiasm demyelination. These findings were confirmed histologically by myelin specific staining. siNgR application resulted in a smaller lesion size compared to control. NgR inhibition significantly increased the numbers of BrdU+/Olig2+ progenitor cells in the lesioned area and in the neurogenic zone of the third ventricle. These progenitor cells (Olig2+ or GFAP+) migrated away from this area as a function of time.Conclusions/Significance
Our results show that inhibition of NgR facilitate myelin repair in the demyelinated chiasm, with enhanced recruitment of proliferating cells to the lesion site. Thus, antagonizing NgR function could have therapeutic potential for demyelinating disorders such as Multiple Sclerosis. 相似文献993.
Waheed Arshad Ihsan-ul- Haq Mohammad Tahir Waheed Kirankumar S. Mysore Bushra Mirza 《PloS one》2014,9(5)
Tomato (Solanum lycopersicum L.) is the second most important cultivated crop next to potato, worldwide. Tomato serves as an important source of antioxidants in human diet. Alternaria solani and Fusarium oxysporum cause early blight and vascular wilt of tomato, respectively, resulting in severe crop losses. The foremost objective of the present study was to generate transgenic tomato plants with rolB gene and evaluate its effect on plant morphology, nutritional contents, yield and resistance against fungal infection. Tomato cv. Rio Grande was transformed via Agrobacterium tumefaciens harbouring rolB gene of Agrobacterium rhizogenes. rolB. Biochemical analyses showed considerable improvement in nutritional quality of transgenic tomato fruits as indicated by 62% increase in lycopene content, 225% in ascorbic acid content, 58% in total phenolics and 26% in free radical scavenging activity. Furthermore, rolB gene significantly improved the defence response of leaves of transgenic plants against two pathogenic fungal strains A. solani and F. oxysporum. Contrarily, transformed plants exhibited altered morphology and reduced fruit yield. In conclusion, rolB gene from A. rhizogenes can be used to generate transgenic tomato with increased nutritional contents of fruits as well as improved foliar tolerance against fungal pathogens. 相似文献
994.
Partha Sen Avinash V. Dharmadhikari Tadeusz Majewski Mahmoud A. Mohammad Tanya V. Kalin Joanna Zabielska Xiaomeng Ren Molly Bray Hannah M. Brown Stephen Welty Sundararajah Thevananther Claire Langston Przemyslaw Szafranski Monica J. Justice Vladimir V. Kalinichenko Anna Gambin John Belmont Pawel Stankiewicz 《PloS one》2014,9(4)
995.
Rehab Mohammad Yusif Irhan Ibrahim Abu Hashim Elham Abdelmonem Mohamed Farid Abd-Elreheim Badria 《AAPS PharmSciTech》2016,17(2):328-338
Currently available anti-ulcer drugs suffer from serious side effects which limited their uses and prompted the need to search for a safe and efficient new anti-ulcer agent. Boswellia gum resin (BR) emerged as a safe, efficient, natural, and economic potential cytoprotective agent. Thus, it is of medical importance to develop gastroretentive (GR) formulations of BR to enhance its bioavailability and anti-ulcer efficacy. Early attempts involved the use of organic solvents and non-applicability to large-scale production. In this study, different tablet formulations were prepared by simple direct compression combining floating and bioadhesion mechanisms employing hydroxypropyl methylcellulose (HPMC), sodium carboxymethyl cellulose (SCMC), pectin (PC), and/or carbopol (CP) as bioadhesive polymers and sodium bicarbonate (SB) as a gas former. The prepared tablets were subjected for assessment of swelling, floating, bioadhesion, and drug release in 0.1 N HCl. The optimized GR formulation was examined for its protective effect on the gastric ulcer induced by indomethacin in albino rabbits compared with lactose tablets. The obtained results disclosed that swelling, floating, bioadhesion, and drug release of the GR tablets of BR depend mainly on the nature of the matrix and the ratio of polymer combinations. Moreover, a combination of SCMC-CP in a ratio of 2:1 (SCP21) exhibited desirable floating, bioadhesion, swelling, and extended drug release. Also, a 6-h pretreatment with SCP21 tablets decreased the severity of inflammation and number of bleeding spots among ulcer-induced rabbits in comparison to those treated with lactose tablets. 相似文献
996.
Mohammad Ali Amanda K. Debes Francisco J. Luquero Deok Ryun Kim Je Yeon Park Laura Digilio Byomkesh Manna Suman Kanungo Shanta Dutta Dipika Sur Sujit K. Bhattacharya David A. Sack 《PLoS medicine》2016,13(9)
IntroductionVaccinating a buffer of individuals around a case (ring vaccination) has the potential to target those who are at highest risk of infection, reducing the number of doses needed to control a disease. We explored the potential vaccine effectiveness (VE) of oral cholera vaccines (OCVs) for such a strategy.ConclusionsThese findings suggest that high-level protection can be achieved if individuals living close to cholera cases are living in a high coverage ring. Since this was an observational study including participants who had received two doses of vaccine (or placebo) in the clinical trial, further studies are needed to determine whether a ring vaccination strategy, in which vaccine is given quickly to those living close to a case, is feasible and effective.
Trial registration
ClinicalTrials.gov NCT00289224 相似文献997.
Ali Behrad Vakylabad Mahin Schaffie Ali Naseri Mohammad Ranjbar Zahra Manafi 《Bioprocess and biosystems engineering》2016,39(7):1081-1104
In this investigation, copper was bioleached from a low-grade chalcopyrite ore using a chloride-containing lixiviant. In this regard, firstly, the composition of the bacterial culture media was designed to control the cost in commercial application. The bacterial culture used in this process was acclimated to the presence of chloride in the lixiviant. Practically speaking, the modified culture helped the bio-heap-leaching system operate in the chloridic media. Compared to the copper recovery from the low-grade chalcopyrite by bioleaching in the absence of chloride, bioleaching in the presence of chloride resulted in improved copper recovery. The composition of the lixiviant used in this study was a modification with respect to the basal salts in 9 K medium to optimize the leaching process. When leaching the ore in columns, 76.81 % Cu (based on solid residues of bioleaching operation) was recovered by staged leaching with lixiviant containing 34.22 mM NaCl. The quantitative findings were supported by SEM/EDS observations, X-ray elemental mapping, and mineralogical analysis of the ore before and after leaching. Finally, Adaptive neuro-fuzzy inference system (ANFIS) was used to simulate the operational parameters affecting the bioleaching operation in chloride–sulfate system. 相似文献
998.
Hyperglycemia and impaired insulin signaling are considered as major factors in the retinal pathology in diabetic retinopathy (DR). Numerous reports support that these two factors damage retinal glial as well as neuronal cells early in diabetes. However, it is not known whether diabetic induced hyperglycemia causes a depression to the insulin signaling. In this study we utilized a well characterized cultured Muller cells (TR-MUL) where we found a high expression of insulin receptor molecules. TR-MUL Cells were treated with high glucose, glutamate and hydrogen peroxide, and activated with insulin. Following treatments, cell lysates were analyzed by immunoblotting experiments for insulin receptor (IRβ) and insulin receptor substrate (IRS1). In addition, cell lysates were immunoprecipitated using antibodies against insulin receptor proteins to analyze tyrosine phosphorylation and serine phosphorylation of insulin receptor proteins. Results indicate that hyperglycemia did not affect the expression of insulin receptor proteins in cultured TR-MUL cells. Although, hyperglycemia seems to inhibit the interaction between IRS1 and IRβ. Hydrogen peroxide increased the tyrosine phosphorylation of insulin receptor proteins but excess glutamate could not affect the insulin receptor proteins indicating that glutamate may not cause oxidative stress in TR-MUL cells. Hyperglycemia lowered serine phosphorylation of IRSser632 and IRSser1101 however, IRSser307 was not affected. Thus, hyperglycemia may not affect insulin signaling through tyrosine phosphorylation of insulin receptor proteins but may inhibit the interactions between insulin receptor proteins. Hyperglycemia induced phosphorylation of various serine residues of IRS1 and their influence on insulin signaling needs further investigation in TR-MUL cells. 相似文献
999.
During work on a new synopsis on the genus Bromus L. for the ‘Flora Iranica’ region, an Afghan perennial brome grass previously identified as the Caucasian B. biebersteinii Roem. & Schult., was found to be a new species. It is described here as B. salangensis sp. nov. This discovery rejected the record of B. biebersteinii for Afghanistan. 相似文献
1000.