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61.
Elizabeth?J?Rahn Tommaso?Iannitti Renee?R?Donahue Bradley?K?TaylorEmail author 《Biology of sex differences》2014,5(1):4
Background
Multiple sclerosis (MS), a demyelinating disease of the central nervous system, is one of the most prevalent neurological disorders in the industrialized world. This disease afflicts more than two million people worldwide, over two thirds of which are women. MS is typically diagnosed between the ages of 20–40 and can produce debilitating neurological impairments including muscle spasticity, muscle paralysis, and chronic pain. Despite the large sex disparity in MS prevalence, clinical and basic research investigations of how sex and estrous cycle impact development, duration, and severity of neurological impairments and pain symptoms are limited. To help address these questions, we evaluated behavioral signs of sensory and motor functions in one of the most widely characterized animal models of MS, the experimental autoimmune encephalomyelitis (EAE) model.Methods
C57BL/6 male and female mice received flank injection of complete Freund’s adjuvant (CFA) or CFA plus myelin oligodendrocyte glycoprotein 35-55 (MOG35-55) to induce EAE. Experiment 1 evaluated sex differences of EAE-induced neurological motor deficits and neuropathic pain-like behavior over 3 weeks, while experiment 2 evaluated the effect of estrous phase in female mice on the same behavioral measures for 3 months. EAE-induced neurological motor deficits including gait analysis and forelimb grip strength were assessed. Neuropathic pain-like behaviors evaluated included sensitivity to mechanical, cold, and heat stimulations. Estrous cycle was determined daily via vaginal lavage.Results
MOG35-55-induced EAE produced neurological impairments (i.e., motor dysfunction) including mild paralysis and decreases in grip strength in both females and males. MOG35-55 produced behavioral signs of neuropathic pain—mechanical and cold hypersensitivity—in females, but not males. MOG35-55 did not change cutaneous heat sensitivity in either sex. Administration of CFA or CFA?+?MOG35-55 prolonged the time spent in diestrus for 2 weeks, after which normal cycling returned. MOG35-55 produced fewer neurological motor deficits when mice were in proestrus relative to non-proestrus phases.Conclusions
We conclude that female mice are superior to males for the study of neuropathic pain-like behaviors associated with MOG35-55-induced EAE. Further, proestrus may be protective against EAE-induced neurological deficits, thus necessitating further investigation into the impact that estrous cycle exerts on MS symptoms.62.
Dispersal failure contributes to plant losses in NW Europe 总被引:1,自引:0,他引:1
Wim A. Ozinga Christine Römermann Renée M. Bekker reas Prinzing Wil L. M. Tamis Joop H. J. Schaminée Stephan M. Hennekens Ken Thompson Peter Poschlod Michael Kleyer Jan P. Bakker Jan M. van Groenendael 《Ecology letters》2009,12(1):66-74
The ongoing decline of many plant species in Northwest Europe indicates that traditional conservation measures to improve the habitat quality, although useful, are not enough to halt diversity losses. Using recent databases, we show for the first time that differences between species in adaptations to various dispersal vectors, in combination with changes in the availability of these vectors, contribute significantly to explaining losses in plant diversity in Northwest Europe in the 20th century. Species with water- or fur-assisted dispersal are over-represented among declining species, while others (wind- or bird-assisted dispersal) are under-represented. Our analysis indicates that the 'colonization deficit' due to a degraded dispersal infrastructure is no less important in explaining plant diversity losses than the more commonly accepted effect of eutrophication and associated niche-based processes. Our findings call for measures that aim to restore the dispersal infrastructure across entire regions and that go beyond current conservation practices. 相似文献
63.
64.
Georg Fertig Hans Peter Rahn Axel Angermann Martina Klöppinger Herbert Georg Miltenburger 《Cytotechnology》1993,11(1):67-75
We have investigated large scale production processes (up to 2 liters) of recombinant proteins using the baculovirus expression system in order to optimize the product yields. Experiments using cell lines ofSpodoptera frugiperda (Sf9) andMamestra brassicae (IZD-Mb0503) were performed to show the different production capacities of the cell lines. The influence of the infection at different cell densities is described. Beyond that, TC100-, IPL41- and serum-free IPL41-medium were compared to demonstrate their different capabilities of supporting cell growth and protein expression. Additionally, the inhibitory effect of FCS on the protease activity of kallikrein, which is produced in its zymogenic form, is discussed. Improved production parameters are described, which enabled us to produce up to 8000 units of activated pro-kallikrein within 14 days using perfusion cultivation.Abbreviations AcNPV
autographa californica nuclear polyhedrosis virus
- MOI
multiplicity of infection 相似文献
65.
66.
67.
Martin Fussenegger reas F. Kahrs Dirk Facius Thomas F. Meyer 《Molecular microbiology》1996,19(6):1357-1372
We characterized a novel mutant phenotype (t etrap ac , tpc) of Neisseria gonorrhoeae (Ngo) associated with a distinctive rough-colony morphology and bacterial growth in clusters of four. This phenotype, suggesting a defect in cell division, was isolated from a mutant library of Ngo MS11 generated with the phoA minitransposon TnMax4. The tpc mutant shows a 30% reduction in the overall murein hydrolase activity using Escherichia coli murein as substrate. Tetrapacs can be resolved by co-cultivation with wild-type Ngo, indicating that Tpc is a diffusible protein. Interestingly, Tpc is absolutely required for the natural transformation competence of piliated Ngo. Mutants in tpc grow normally, but show a ~ 10-fold reduction in their ability to invade human epithelial cells. The tpc sequence reveals an open reading frame of ~1 kb encoding a protein (Tpc) of 37kDa. The primary gene product exhibits an N-terminal leader sequence typical of lipoproteins, but palmitoylation of Tpc could not be demonstrated. The ribosomal binding site of tpc is immediately downstream of the translational stop codon of the folC gene coding for an enzyme involved in folic acid biosynthesis and one-carbon metabolism. The tpc gene is probably co-transcribed from the folC promoter and a promoter located within the folC gene. The latter promoter sequence shares significant homology with E. coli gearbox consensus promoters. All three mutant phenotypes, i.e. the cell separation defect, the transformation deficiency and the defect in cell invasion can be restored by complementation of the mutant with an intact tpc gene. To some extent the tcp phenotype is reminiscent of iap in Listeria, lytA in Streptococcus pneumoniae and lyt in Bacillus subtilis, all of which are considered to represent murein hydrolase defects. 相似文献
68.
Hartmut Weiler-Güttler Michaela Sommerfeldt Anastasia Papandrikopoulou Uwe Mischek Dorothea Bonitz reas Frey Matthias Grupe Joachim Scheerer Hans G. Gassen 《Journal of neurochemistry》1990,54(2):444-450
In an approach toward the identification of hitherto unknown proteins involved in the function of the blood-brain barrier, we constructed a pig brain microvessel-derived cDNA library that is enriched in blood-brain barrier specific sequences by means of subtractive cloning. Sequence analysis of selected clones revealed that one of the cDNAs encoded porcine apolipoprotein (apo) A-1. The identity of apo A-1 mRNA was further confirmed by in vitro translation of RNA from brain microvascular endothelial cells and subsequent immunoprecipitation with an antibody against human apo A-1. We further investigated the expression of apo A-1 mRNA in several tissues and in endothelial cells of the pig. It is shown that cultured brain microvascular endothelial cells provide an in vitro model to study the expression and function of apo A-1 in the microvasculature of the brain. 相似文献
69.
Bruno M. Moerschbacher Ulrike Noll Carlos A. Ocampo Berenike E. Flott Uwe Gotthardt reas Wüslefeld Hans-Joachim Reisener 《Physiologia plantarum》1990,78(4):609-615
Seven-day-old seedlings of the near-isogenic wheat ( Triticum aestivum L.) lines Prelude and Prelude-Sr5, susceptible and resistant to wheat stem rust, respectively, were inoculated with uredospores of the oat crown rust fungus Puccinia coronata Cda. f. sp. avenae Fraser & Led. Fluorescence microscopy revealed that the majority of colonies developed intercellular infection structures including haustorial mother cells and haustoria after penetration of wheat mesophyll cells. All penetrated cells became necrotic, and exhibited bright yellow autofluorescence. This autofluorescence was not extractable with alkali, and fluorescent cells stained positively with phloroglucinol/HCI, suggesting that hypersensitive cell death was correlated with cellular lignification. Accordingly, the lignin biosynthetic enzymes phenylalanine ammonia-lyase (EC4.3.1.5). 4-coumarate:CoA ligase (EC6.2.1.12), cinnamyl-alcohol dehydrogenase (EC1.1.1.149), and peroxidases (EC1.11.1.7) increased in activity during the expression of resistance. The induced pattern of peroxidase iso/ymes closely resembled that observed for highly incompatible wheat/wheat stem rust interactions. Furthermore, an elieitor was extracted from oat crown rust germlings. which induces lignification when injected into the intercellular space of wheat leaves. This elieitor appears to be functionally similar to that isolated from wheat stem rust germlings. The results suggest that the non-host resistance of wheat to the xenopara-site oat crown rust closely resembles the race/cullivar-speeific resistant mechanism of highly resistant wheat varieties to wheat stem rust. 相似文献
70.
Jürg Schmid reas Schaller Urs Leibinger Werner Boll Nikolaus Amrhein 《The Plant journal : for cell and molecular biology》1992,2(3):375-383
Full-length cDNA clones encoding shikimate kinase (EC 2.7.1.71), an enzyme of the central section of the shikimate pathway, have been isolated from tomato (Lycopersicon esculentum L., cv. UC82b). The open reading frame has the capacity to encode a peptide of 300 amino acids. The in-vitro synthesized peptide catalysed the phosphorylation of shikimate thus confirming the identity of the isolated cDNA clones. The N-terminal portion of the deduced amino acid sequence resembles known chloroplast-specific transit peptides. The existence of such a transit peptide was proven by the uptake of the in-vitro synthesized peptide as well as its processing by isolated chloroplasts. Multiple sites of polyadenylation were observed in shikimate kinase mRNAs. The results of Northern and Southern blot analyses are consistent with the existence of only one shikimate kinase gene per haploid genome in tomato. These results are discussed with respect to the dual pathway hypothesis of the shikimate pathway in higher plants. 相似文献