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581.
Y. Akkhawattanangkul P. Maiti Y. Xue D. Aryal W. C. Wetsel D. Hamilton S. C. Fowler M. P. McDonald 《Genes, Brain & Behavior》2017,16(5):522-536
Parkinson's disease is a debilitating neurodegenerative condition for which there is no cure. Converging evidence implicates gangliosides in the pathogenesis of several neurodegenerative diseases, suggesting a potential new class of therapeutic targets. We have shown that interventions that simultaneously increase the neuroprotective GM1 ganglioside and decrease the pro‐apoptotic GD3 ganglioside – such as inhibition of GD3 synthase (GD3S) or administration of sialidase – are neuroprotective in vitro and in a number of preclinical models. In this study, we investigated the effects of GD3S deletion on parkinsonism induced by 1‐methyl‐4phenyl‐1,2,3,6‐tetrahydropyridine (MPTP). MPTP was administered to GD3S?/? mice or controls using a subchronic regimen consisting of three series of low‐dose injections (11 mg/kg/day × 5 days each, 3 weeks apart), and motor function was assessed after each. The typical battery of tests used to assess parkinsonism failed to detect deficits in MPTP‐treated mice. More sensitive measures – such as the force‐plate actimeter and treadmill gait parameters – detected subtle effects of MPTP, some of which were absent in mice lacking GD3S. In wild‐type mice, MPTP destroyed 53% of the tyrosine‐hydroxylase (TH)‐positive neurons in the substantia nigra pars compacta (SNc) and reduced striatal dopamine 60.7%. In contrast, lesion size was only 22.5% in GD3S?/? mice and striatal dopamine was reduced by 37.2%. Stereological counts of Nissl‐positive SNc neurons that did not express TH suggest that neuroprotection was complete but TH expression was suppressed in some cells. These results show that inhibition of GD3S has neuroprotective properties in the MPTP model and may warrant further investigation as a therapeutic target. 相似文献
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583.
The present investigation was carried out on oviductal activity during the annual ovarian cycle of the Indian tree pie (Dendrocitta vagabunda). The oviductal activity was evaluated by weight, length, histology (gross and quantitative) and peroxidase, acid phosphatase, alkaline phosphatase, sialic acid, glycogen, RNA and protein concentrations of different regions of the oviduct. All these values w ere low during the nonbreeding phase (August to January), increased during the progressive phase (February to March), became maximum during breeding (April to May) and decreased in the regression phase (June to July). The functional change of the oviduct is suggested to be due to fluctuation of ovarian steroid activity in this avian species. 相似文献
584.
Sonakshi Maiti J. Jayaramudu Kunal Das Siva Mohan Reddy Rotimi Sadiku Suprakas Sinha Ray Dagang Liu 《Carbohydrate polymers》2013
Three different precursor materials – 1. China cotton, 2. South African cotton, 3. Waste tissue papers were used to produce nano-cellulose by acid hydrolysis route. No chemical pretreatment has been done for the production of nano-cellulose from these precursors. Prepared nano-cellulose and their corresponding precursor materials were characterized by transmission electron microscopy (TEM), particle size analysis, X-ray diffraction (XRD) study, thermo gravimetric analysis (TGA), differential scanning calorimetric (DSC) analysis and Fourier transformed infra red (FTIR) spectroscopy. A comparative study of the characteristics was done with the properties of raw materials and with that of nano-cellulose. Shape and size of the nano cellulose generally depends on nature of the precursor and hydrolysis condition. Morphology study of nano-cellulose from different sources revealed range of length from 50 to 200 nm and diameter from 10 to 90 nm. Higher thermal stability and crystallinity of nano-cellulose were observed compared to that of precursor from TGA/DSC study. 相似文献
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The sclerotia of Sclerotium rolfsii Sacc. survived in natural soil for 225 days under controlled moisture at 50% water holding capacity (WHC) after which there was a progressive reduction in the population of viable sclerotia. At 390 days only 48% were recovered. Sclerotia survived well at moisture contents upto 75% WHC but at 100% the population declined rapidly and none were recovered after 60 days. The contents of the sclerotia were found to lyse without germination leaving hollow rinds. Such lysis was found to be favoured between 25 and 40°C. At and below 20°C no such lysis was recovered and more than 80% sclerotia were recovered even after 60 days. 相似文献
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589.
Overproduction of an alkali- and thermo-stable xylanase in tobacco chloroplasts and efficient recovery of the enzyme 总被引:5,自引:0,他引:5
Leelavathi Sadhu Gupta Naveen Maiti Shankar Ghosh Amit Siva Reddy Vanga 《Molecular breeding : new strategies in plant improvement》2003,11(1):59-67
Overproduction of cellulolytic enzymes through conventional nucleartransformation approaches posed a major challenge as they can potentiallydegrade the cell wall components and thereby affect transgenic plant growth anddevelopment. In this study, we have tested the possibility to over produce analkali-thermostable xylanase gene from Bacillus sp. StrainNG-27 in tobacco plants through chloroplast expression. Our results showed thatthe xylanase expression can reach up to 6% of the total soluble protein, avaluecomparable to high level expression reported for several non-cellulolyticproteins in tobacco chloroplasts. The chloroplast-expressed xylanase retainedits activity even when the leaves were dried under sun or at 42°C, offering flexibility in the agricultural system intransport and storage. The recombinant enzyme was purified to homogeneity usingsingle step chromatography with more than 85% recovery. Most importantly,transgenic plants were indistinguishable from the control untransformed plantsin their morphology, growth and in seed setting. These results open up newavenues for large scale production of several other industrially usefulcellulolytic enzymes through chloroplast expression. 相似文献
590.
Best linear unbiased prediction is well known for its wide rangeof applications including small area estimation. While the theoryis well established for mixed linear models and under normalityof the error and mixing distributions, the literature is sparsefor nonlinear mixed models under nonnormality of the error distributionor of the mixing distributions. We develop a resampling-basedunified approach for predicting mixed effects under a generalizedmixed model set-up. Second-order-accurate nonnegative estimatorsof mean squared prediction errors are also developed. Giventhe parametric model, the proposed methodology automaticallyproduces estimators of the small area parameters and their meansquared prediction errors, without requiring explicit analyticalexpressions for the mean squared prediction errors. 相似文献