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71.
Identification of Transposable Element Markers for a Rust (Puccinia arachidis Speg.) Resistance Gene in Cultivated Peanut 总被引:1,自引:0,他引:1
Peanut rust (Puccinia arachidis Speg.) affects pod yield and quality up to an extent of 10–50%. Efforts have been made on transferring the rust resistance gene to cultivated peanut species through interspecific hybridization. But, in most of the cases, it failed due to linkage drag of undesirable plant and pod features. Identification of tightly linked molecular markers will help to identify the desirable recombinants more efficiently. A recombinant inbred line population comprising 164 lines was developed from a cross between a rust‐resistant parent VG 9514 and a rust susceptible parent TAG 24. Using a modified bulk segregant analysis, 243 transposable element (TE) primer pairs were screened for putative linkage with rust resistance. Of the 243, 40 TE primer pairs were found polymorphic between parents and two transposable element markers, and TE 360 and TE 498 were found associated with rust resistance gene. Based on genetic mapping, TE 360 was found linked to the rust resistance gene at 4.5 cM distance. Identification of such markers could be applied for marker‐assisted selection of rust resistance plants in peanut. 相似文献
72.
Lal Mahalle Ayse Alemdar Mihaela Mihai Nathalie Legros 《The International Journal of Life Cycle Assessment》2014,19(6):1305-1315
Purpose
Biopolymers are considered to be environmentally friendlier than petroleum-based polymers, but little is known about their environmental performance against petroleum-based products. This paper presents the results of a life cycle assessment (LCA) of two prototype biocomposite formulations produced by extrusion of wood fibre with either polylactic acid (PLA) or a blend of PLA and locally produced thermoplastic starch (TPS).Methods
The study followed the LCA methodology outlined in the two standards set out by the International Organization for Standardization (ISO): ISO 14040 and ISO 14044 of 2006. A life cycle inventory (LCI) for the biocomposite formulations was developed, and a contribution analysis was performed to identify the significant inputs. Environmental performances of the two formulations were then compared with each other and polypropylene (PP), a petroleum-based polymer. The US Environmental Protection Agency’s impact assessment method, “TRACI: The Tool for the Reduction and Assessment of Chemical and Other Environmental Impacts”, was combined with Cumulative Energy Demand (a European method) in order to characterize the inventory flows. Environmental impact categories chosen for the analysis were the following: global warming, stratospheric ozone depletion, acidification of land and water, eutrophication, smog, human health (respiratory, carcinogenic, and non-carcinogenic) effects and ecotoxicity.Results and discussion
We found that PLA is the significant input which contributes mostly to fossil fuel consumption, acidification and respiratory and smog effects. Impacts from PLA transport from the faraway source significantly added more burden to its contributions. TPS causes less environmental burden compared to PLA; the environmental performance of the biocomposite improved when a blend of PLA and TPS is used in formulating the biocomposite. The two formulations performed better than PP in all the environmental impact categories except eutrophication effects, which is important on a regional basis.Conclusions
The following conclusions were drawn from this study:- PLA is the environmentally significant input among the three raw materials.
- TPS causes less environmental burden than PLA. Environmental performance of the biocomposite improves in the life cycle energy consumption, fossil energy use, ozone depletion and non-carcinogenic impact categories when a blend of PLA and TPS is used.
- The biocomposite can outperform PP in all the impact categories except eutrophication effects if manufactured using hydroelectricity.
73.
74.
Background
Current guidelines recommend the use of Escherichia coli (EC) or thermotolerant (“fecal”) coliforms (FC) as indicators of fecal contamination in drinking water. Despite their broad use as measures of water quality, there remains limited evidence for an association between EC or FC and diarrheal illness: a previous review found no evidence for a link between diarrhea and these indicators in household drinking water.Objectives
We conducted a systematic review and meta-analysis to update the results of the previous review with newly available evidence, to explore differences between EC and FC indicators, and to assess the quality of available evidence.Methods
We searched major databases using broad terms for household water quality and diarrhea. We extracted study characteristics and relative risks (RR) from relevant studies. We pooled RRs using random effects models with inverse variance weighting, and used standard methods to evaluate heterogeneity and publication bias.Results
We identified 20 relevant studies; 14 studies provided extractable results for meta-analysis. When combining all studies, we found no association between EC or FC and diarrhea (RR 1.26 [95% CI: 0.98, 1.63]). When analyzing EC and FC separately, we found evidence for an association between diarrhea and EC (RR: 1.54 [95% CI: 1.37, 1.74]) but not FC (RR: 1.07 [95% CI: 0.79, 1.45]). Across all studies, we identified several elements of study design and reporting (e.g., timing of outcome and exposure measurement, accounting for correlated outcomes) that could be improved upon in future studies that evaluate the association between drinking water contamination and health.Conclusions
Our findings, based on a review of the published literature, suggest that these two coliform groups have different associations with diarrhea in household drinking water. Our results support the use of EC as a fecal indicator in household drinking water. 相似文献75.
Hande Ozgen Waldemar Schrimpf Jelle Hendrix Jenny C. de Jonge Don C. Lamb Dick Hoekstra Nicoletta Kahya Wia Baron 《PloS one》2014,9(7)
In the central nervous system, lipid-protein interactions are pivotal for myelin maintenance, as these interactions regulate protein transport to the myelin membrane as well as the molecular organization within the sheath. To improve our understanding of the fundamental properties of myelin, we focused here on the lateral membrane organization and dynamics of peripheral membrane protein 18.5-kDa myelin basic protein (MBP) and transmembrane protein proteolipid protein (PLP) as a function of the typical myelin lipids galactosylceramide (GalC), and sulfatide, and exogenous factors such as the extracellular matrix proteins laminin-2 and fibronectin, employing an oligodendrocyte cell line, selectively expressing the desired galactolipids. The dynamics of MBP were monitored by z-scan point fluorescence correlation spectroscopy (FCS) and raster image correlation spectroscopy (RICS), while PLP dynamics in living cells were investigated by circular scanning FCS. The data revealed that on an inert substrate the diffusion rate of 18.5-kDa MBP increased in GalC-expressing cells, while the diffusion coefficient of PLP was decreased in sulfatide-containing cells. Similarly, when cells were grown on myelination-promoting laminin-2, the lateral diffusion coefficient of PLP was decreased in sulfatide-containing cells. In contrast, PLP''s diffusion rate increased substantially when these cells were grown on myelination-inhibiting fibronectin. Additional biochemical analyses revealed that the observed differences in lateral diffusion coefficients of both proteins can be explained by differences in their biophysical, i.e., galactolipid environment, specifically with regard to their association with lipid rafts. Given the persistence of pathological fibronectin aggregates in multiple sclerosis lesions, this fundamental insight into the nature and dynamics of lipid-protein interactions will be instrumental in developing myelin regenerative strategies. 相似文献
76.
Blanca Arango-Gonzalez Dragana Trifunovi? Ayse Sahaboglu Katharina Kranz Stylianos Michalakis Pietro Farinelli Susanne Koch Fred Koch Sandra Cottet Ulrike Janssen-Bienhold Karin Dedek Martin Biel Eberhart Zrenner Thomas Euler Per Ekstr?m Marius Ueffing Fran?ois Paquet-Durand 《PloS one》2014,9(11)
Cell death in neurodegenerative diseases is often thought to be governed by apoptosis; however, an increasing body of evidence suggests the involvement of alternative cell death mechanisms in neuronal degeneration. We studied retinal neurodegeneration using 10 different animal models, covering all major groups of hereditary human blindness (rd1, rd2, rd10, Cngb1 KO, Rho KO, S334ter, P23H, Cnga3 KO, cpfl1, Rpe65 KO), by investigating metabolic processes relevant for different forms of cell death. We show that apoptosis plays only a minor role in the inherited forms of retinal neurodegeneration studied, where instead, a non-apoptotic degenerative mechanism common to all mutants is of major importance. Hallmark features of this pathway are activation of histone deacetylase, poly-ADP-ribose-polymerase, and calpain, as well as accumulation of cyclic guanosine monophosphate and poly-ADP-ribose. Our work thus demonstrates the prevalence of alternative cell death mechanisms in inherited retinal degeneration and provides a rational basis for the design of mutation-independent treatments. 相似文献
77.
Gizem A. Kaya Ayse N. Co?kun Vuslat Y?lmaz Piraye Oflazer Ye?im Gülsen-Parman Fikret Aysal Rian Disci Haner Direskeneli Alexander Marx Feza Deymeer Güher Saruhan-Direskeneli 《PloS one》2014,9(8)
A functional single nucleotide polymorphism (SNP) of the PTPN22 gene encoding a protein tyrosine phosphatase has been associated with autoimmune disorders including myasthenia gravis (MG). As the PTPN22 R620W polymorphism has a wide variation of allele frequencies among different populations, this polymorphism was investigated in MG in Turkey. An emphasis is put on MG subgroups according to autoantibody (Abs) production and presence of thymoma. DNA samples from 416 patients with clinically diagnosed generalized MG (231 with Abs to acetylcholine receptor, AChR-MG), 53 with Abs to muscle-specific kinase (MuSK-MG), 55 patients with no detectable Abs (SN-MG), 77 patients with thymoma (TAMG) and 293 healthy controls (HC) were genotyped for the SNP (PTPN22 R620W, C1858T, rs2476601). The PTPN22 T allele was increased in AChR-MG patients (odds ratio [OR]: 2.5, 95%CI: 1.2–5.1). The association was stronger in late disease-onset AChR (LOMG, OR: 3.1, 95%CI: 1.2–8.2). MuSK-MG, SN-MG and TAMG groups did not carry the variant allele more frequently than the HC. In contrast to findings in other autoimmune diseases, the distribution of the PTPN22 polymorphism in this population provides a susceptibility marker for AChR-MG. The strongest association is detected in patients with LOMG. 相似文献
78.
Rafig Gurbanov Nihal S. Ozek Sinem Tunçer Feride Severcan Ayse G. Gozen 《Journal of biophotonics》2018,11(5)
In this study, the molecular profile changes leading to the adaptation of bacteria to survive and grow at inhibitory silver concentration were explored. The profile obtained through infrared (IR)‐based measurements indicated extensive changes in all biomolecular components, which were supported by chemometric techniques. The changes in biomolecular profile were prominent, including nucleic acids. The changes in nucleic acid region (1350‐950 cm?1) were encountered as a clue for conformational change in DNA. Further analysis of DNA by IR spectroscopy revealed changes in the backbone and sugar conformations. Moreover, Enzyme‐Linked Immunosorbent Assay‐based measurements of DNA methylation levels were performed to see if epigenetic mechanisms are in operation during bacterial adaptation to this environmental challenge. The results indicated a notable demethylation in Escherichia coli and methylation in Staphylococcus aureus likely to be associated with their elaborate adaptation process to sustain survival and growth. 相似文献
79.
Lingdong Li Yanan Jin Hao Zhou Hande Wang 《Bioorganic & medicinal chemistry letters》2018,28(23-24):3665-3669
Two novel zwitterionic N-chlorohydantoin biocides, containing an N-chlorohydantoin unit and a sulfobetaine unit or a carboxybetaine unit, were chemically synthesized and characterized. Using the quaternary ammonium N-chlorohydantoin as control, the antibacterial activity of synthetic zwitterionic N-chlorohydantoins was challenged and the antibacterial data showed that carboxybetaine N-chlorohydantoin exhibited distinctively higher biocidal efficacy than QA counterpart, while sulfobetaine N-chlorohydantoin displayed slightly inferior antimicrobial efficacy. Our results may inspire further exploration of more zwitterionic N-chlorohydantoin analogs for antibacterial application. 相似文献
80.
Genome‐wide identification,expression profiling,and target gene analysis of microRNAs in the Onion thrips,Thrips tabaci Lindeman (Thysanoptera: Thripidae), vectors of tospoviruses (Bunyaviridae) 下载免费PDF全文