Genetics. Toward a new vocabulary of human genetic variation     

Sankar P  Cho MK 《Science (New York, N.Y.)》2002,298(5597):1337-1338

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TDP-43 mutations in familial and sporadic amyotrophic lateral sclerosis   总被引：1，自引：0，他引：1  

Sreedharan J  Blair IP  Tripathi VB  Hu X  Vance C  Rogelj B  Ackerley S  Durnall JC  Williams KL  Buratti E  Baralle F  de Belleroche J  Mitchell JD  Leigh PN  Al-Chalabi A  Miller CC  Nicholson G  Shaw CE 《Science (New York, N.Y.)》2008,319(5870):1668-1672

Amyotrophic lateral sclerosis (ALS) is a fatal motor neuron disorder characterized pathologically by ubiquitinated TAR DNA binding protein (TDP-43) inclusions. The function of TDP-43 in the nervous system is uncertain, and a mechanistic role in neurodegeneration remains speculative. We identified neighboring mutations in a highly conserved region of TARDBP in sporadic and familial ALS cases. TARDBPM337V segregated with disease within one kindred and a genome-wide scan confirmed that linkage was restricted to chromosome 1p36, which contains the TARDBP locus. Mutant forms of TDP-43 fragmented in vitro more readily than wild type and, in vivo, caused neural apoptosis and developmental delay in the chick embryo. Our evidence suggests a pathophysiological link between TDP-43 and ALS.  相似文献   

Infection processes and soft wheat response to root rot and crown rot caused by Fusarium culmorum     

G. Beccari  L. Covarelli  P. Nicholson 《Plant pathology》2011,60(4):671-684

An isolate of the fungus Fusarium culmorum constitutively expressing green fluorescent protein was used to investigate the infection process and host response of primary seedling roots and stem base leaf sheaths of soft wheat cv. Genio. Disease progress was assessed macroscopically by visual symptoms, microscopically by confocal laser scanning microscopy (CLSM) and via gene expression analysis of fungal and wheat genes by real‐time quantitative RT‐PCR. In the roots, CLSM investigations revealed an initial intercellular and subsequent intracellular colonization by fungal hyphae. The fungus invaded the rhizodermal layer and cortex but was not seen to colonize the stele. The fungus consistently expressed TRI5 (24, 48 and 96 h post‐inoculation), indicating that trichothecenes were being synthesized throughout this phase of infection and colonization. The expression of the six host defence‐associated genes (Wheatwin 1‐2, PR1, Chitinase, PAL, WIR1 and LOX) increased early in infection and decreased during later stages. In the stem base, CLSM observations revealed the fungus sequentially penetrating though the first, second and third basal leaf sheaths. Expression of TRI5 was initiated early in the infection of each leaf sheath. The expression of the host defence‐associated genes varied over time and across leaf sheaths, and all were also expressed in leaf sheaths which had not yet been in contact with the fungus. Expression of LOX and WIR1 were particularly enhanced in the third leaf sheath.  相似文献   

IT—Information Technology and the Human Interface: A Review of the Environmental Effects of Different Livestock Manure Storage Systems, and a Suggested Procedure for Assigning Environmental Ratings     

R. J. Nicholson  J. Webb  A. Moore 《Biosystems Engineering》2002,81(4):363

There are concerns over a range of adverse environmental effects resulting from the storage of livestock manures on farms. The objectives of this study were to examine all the likely environmental effects of different storage methods, and to recommend which were the most desirable options.Literature reviews were undertaken to identify the likely environmental consequences of each commonly used storage method, in terms of water pollution risks, odour and ammonia emissions, greenhouse gas emissions and survival of microorganisms during storage. Planning and landscape aspects were considered and the most feasible options for abatement of ammonia emissions were identified. An ‘environmental rating’ for different storage systems was then devised, with the aim of obtaining a balance between water pollution, aerial emissions and other concerns.The environmental rating exercise favoured the more sophisticated and hence most expensive storage methods. No large differences emerged between ratings for slurry systems and solid systems when ease of adding ammonia control measures was excluded. For pigs, slurry systems appear to have a slight advantage, because of the greater ammonia emissions from the solid pig manure. The use of such a rating system could be developed further as more data become available. Whilst the method indicates the relative desirability of systems at a national scale it could be adapted to take account of local considerations or those of individual farm sites.  相似文献   

Facts and fallacies concerning mercury uptake by fish in acid stressed lakes     

Lisa A. Richman  Christopher D. Wren  Pamela M. STokes 《Water, air, and soil pollution》1988,37(3-4):465-473

Concerns about Hg contamination of fish have changed in emphasis from Hg-contaminated systems to more remote and apparently unpolluted systems. For remote lakes, a negative relationship between lake pH and Hg in fish has been demonstrated, implying an effect on Hg uptake from lake acidification. Though this relationship was discussed, and hypotheses put forward concerning the possible mechanisms 8 yr ago, the factors regulating Hg uptake by aquatic biota are still poorly understood. Several recent studies have prompted workers to observe that frequently cited concepts about processes affecting Hg accumulation and cycling are in fact over-simplifications. This review attempts to synthesize and clarify the present state of knowledge. We critically evaluate evidence for a number of controlling factors in the context of the concentrations, the chemical species and the biological uptake processes for Hg. The factors include: trophic status and organic content of water, food chain transfer and biomagnification of Hg, organism age and size effects, feeding strategies, biological and chemical methylation, concentration of cations including H⁺ and Ca²⁺ and the immediate source of Hg.  相似文献   

In vivo investigation of changes in biomarkers of oxidative stress induced by plant food rich diets     

Thompson HJ  Heimendinger J  Gillette C  Sedlacek SM  Haegele A  O'neill C  Wolfe P 《Journal of agricultural and food chemistry》2005,53(15):6126-6132

It is well established that vegetables and fruit (VF) contain antioxidant phytochemicals. Consequently, it is expected that individuals who consume diets with a high content of VF should be better protected against oxidative cellular damage than individuals who do not, but not all data support this assumption. The objective of this study was to identify possible explanations for this conundrum. The effects of two diets that differed in VF content on markers of oxidative damage were studied. Sixty-four women participated in a 14-day dietary intervention. Subjects consumed on average either 3.6 or 12.1 servings of VF per day. The primary end points assessed were 8-hydroxy-2-deoxyguanosine (8-oxo-dG) in peripheral lymphocyte DNA and 8-isoprostaglandin F-2alpha (8-iso-PGF2alpha) excreted in urine. Subjects consuming the high versus low VF diet had lower concentrations of 8-oxo-dG (p < 0.01) and of 8-iso-PGF2alpha (p < 0.01). However, the reduction in oxidative end points by high VF was not uniform. Rather, an antioxidant effect was observed primarily in individuals whose oxidative end points at baseline were above the median for the study population. Using change in plasma carotenoids (end point minus baseline measurements) as an index of phytochemical intake, the reduction in oxidative markers was inversely proportional to change in plasma carotenoids; this effect was stronger for lipid peroxidation (p < 0.01) than DNA oxidation (p < 0.05). These findings imply that increasing exogenous antioxidant exposure may primarily benefit individuals with elevated levels of oxidative stress. Null findings do not necessarily indicate that an antioxidant compound lacks in vivo activity.  相似文献   

the effect of phosphate on the transformation of ferrihydrite into crystalline products in alkaline media     

Paige  C. R.  Snodgrass  W. J.  Nicholson  Ronald V.  Scharer  J. M.  He  Q. H. 《Water, air, and soil pollution》1997,97(3-4):397-412

The presence of phosphate retards the transformation of ferrihydrite into crystalline products. Increasing phosphate from 0 to 1 mole % results in an order of magnitude decrease in the rate of transformation of ferrihydrite at pH 12. Levels of phosphate of ～1 mol % suppress the formation of goethite (α-FeO(OH)) and result in the formation of a product consisting ofη-Fe₂O₃. Higher levels of phosphate result in the ferrihydrite remaining amorphous, even after several hundred hours. Phosphate prevents formation of goethite by hindering the dissolution of ferrihydrite rather than by interfering with nucleation and growth of goethite in solution. The transformation rate of pure ferrihydrite is also strongly inhibited in the presence of dissolved phosphate. This is due to surface complexation. The transformation rate was measured at temperatures of 60 °C and 70 °C. The rate of transformation was found to be described by either (i) a solid-state reaction equation for powdered compacts or (ii) a zero-order reaction controlled by desorption. The transformation of the ferrihydrite matrix was accompanied by the loss of the phosphate trace component. X-ray diffraction indicates that no solid solution involving phosphate substitution intoη-Fe₂O₃ is formed. Transmission electron microphotographs of the original precipitates containing phosphate confirm the presence of the phosphate and demonstrate its involvement in linking together extremely small particles of ferrihydrite.  相似文献   

Design,Evaluation and Application of a Continuously Stirred Tank Reactor System for Use in Nitric Acid Air Pollutant Studies     

Padgett  Pamela E.  Bytnerowicz  Andrzej  Dawson  Philip J.  Riechers  George H.  Fitz  Dennis R. 《Water, air, and soil pollution》2004,151(1-4):35-51

Nitric acid (HNO₃) vapor is a significant component of air pollution. Dry deposition of HNO₃ is thought to be a major contributor to terrestrial loading of anthropogenically-derived nitrogen (N), but many questions remain regarding the physico-chemical process of deposition and the biological responses to accumulation of dry-deposited HNO₃ on surfaces. To examine these processes experimentally, a continuously stirred tank reactor (CSTR) fumigation system has been constructed. This system enables simultaneous fumigation at several concentrations in working volumes 1.3 m dia by 1.3 m ht, allowing for simultaneous fumigation of many experimental units. Evaluation of the system indicates that it is appropriate for long-term exposures of several months duration and capable of mimicking patterns of diurnal atmospheric HNO₃ concentrations representative of areas with different levels of pollution.  相似文献   

Attenuation of Borrelia anserina by serial passage in liquid medium     

J F Levine  M J Dykstra  W L Nicholson  R L Walker  G Massey  H J Barnes 《Research in veterinary science》1990,48(1):64-69

Borrelia anserina (Sakharoff) was successfully grown in a liquid medium (Barbour-Stoenner-Kelly) for 39 passages. By the 12th serial passage in medium, infectivity of B anserina for chicks was lost. Electron microscopy did not reveal structural differences between non-infective and infective cultured organisms. Changes in the protein profiles were found by electrophoresis as the organisms were passed in culture.  相似文献   

Pest and disease control on intensive apple trees by overhead mobile spraying     

Barry K. Cooke  Pamela J. Herrington  Kenneth G. Jones  Norman G. Morgan 《Pest management science》1975,6(6):571-579

In 3 year field experiments on pest and disease control by mobile overhead spraying of intensive Cox's Orange Pippin apple trees, overhead booms applying 1125 litres/ha and overhead mist-blowing equipment applying 562 litres/ha, each spraying two complete rows from one alley in half the normal time, were compared with conventional automatic mast spraying at 2250 litres/ha and with conventional mist-blowing at 562 litres/ha. The overhead boom application of demeton-S-methyl (0.0036% a.i.) with azinphos-methyl (0.0165% a.i.) or of fenitrothion (0.031% a.i.) at the green cluster stage gave control of the applegrass aphid, Rhopalosiphum insertum, virtually equal to that obtained by conventional application of the same insecticides. Similarly, the overhead mist applications of conventional quantities of insecticides gave equal control, but not when applying one-quarter of the normal amount of insecticides. The conventional methods generally gave better control of apple sucker, Psylla mali. In 1971, when the incidence of apple scab, Venturia inaequalis, was only moderate, the overhead boom method gave equal control to conventional spraying with both dodine/captan (0.03% a.i. and 0.094% a.i.) and benomyl (0.025% a.i.) programmes: in 1972 and 1973, when the scab incidence was heavier, the overhead boom spraying was again equal to the conventional method with the benomyl programme but was less effective with the dodine/captan programme. The overhead mist applications gave control only when the scab incidence was light. Repeated applications of dinocap emulsion (0.025% a.i.), included in the fungicide programme in 1971, gave as good control of the active stages of fruit tree red spider mite, Panonychus ulmi, when applied by the overhead methods as by conventional spraying, but application of the benomyl programme gave poor control. Mobile overhead spraying of small intensive apple trees is a promising method but needs further development before becoming fully acceptable.  相似文献