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Shows Significant Differences (shows + significant_difference)
Selected AbstractsMutagenic probes of the role of Ser209 on the cavity shaping loop of human monoamine oxidase AFEBS JOURNAL, Issue 16 2009Jin Wang The available literature implicating human monoamine oxidase A (MAO A) in apoptotic processes reports levels of MAO A protein that do not correlate with activity, suggesting that unknown mechanisms may be involved in the regulation of catalytic function. Bioinformatic analysis suggests Ser209 as a possible phosphorylation site that may be relevant to catalytic function because it is adjacent to a six-residue loop termed the ,cavity shaping loop' from structural data. To probe the functional role of this site, MAO A Ser209Ala and Ser209Glu mutants were created and investigated. In its membrane-bound form, the MAO A Ser209Glu phosphorylation mimic exhibits catalytic and inhibitor binding properties similar to those of wild-type MAO A. Solubilization in detergent solution and purification of the Ser209Glu mutant results in considerable decreases in these functional parameters. By contrast, the MAO A Ser209Ala mutant exhibits similar catalytic properties to those of wild-type enzyme when purified. Compared to purified wild-type and Ser209Ala MAO A proteins, the Ser209Glu MAO A mutant shows significant differences in covalent flavin fluorescence yield, CD spectra and thermal stability. These structural differences in the purified MAO A Ser209Glu mutant are not exhibited in quantitative structure,activity relationship patterns using a series of para -substituted benzylamine analogs similar to the wild-type enzyme. These data suggest that Ser209 in MAO A does not appear to be the putative phosphorylation site for regulation of MAO A activity and demonstrate that the membrane environment plays a significant role in stabilizing the structure of MAO A and its mutant forms. [source] Fruit size and picking scar size in some blueberry commercial cultivars and hybrid plants grown in SW SpainINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 7 2007Raquel Parra Summary Within a blueberry research program in SW Spain, five rabbiteye (Vaccinium ashei Reade) and nine southern highbush (Vaccinium corymbosum L.) commercial cultivars along with 38 hybrid plants, produced by crossing highbush and rabbiteye cultivars, were used. The differences in the fruit size and the picking scar size among the plants, and the annual differences within each plant were studied. No significant differences were found in the fruit length, width, weight and the picking scar size between the rabbiteye and the southern highbush cultivars, and neither between the cultivars and the hybrid progeny. However, significant differences were found among the cultivars and among the hybrid plants. The picking scar size correlates better with fruit width and weight than with fruit length, although correlation values are not high. Thus, outliers were observed, some of them interesting to be selected for having large fruits and narrow scars. The ratio between the picking scar and fruit width shows significant differences among subsequent years in many hybrid plants. [source] Bone Fragility and Collagen Cross-Links,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 12 2004Eleftherios P Paschalis Abstract Infrared imaging analysis of iliac crest biopsy specimens from patients with osteoporotic and multiple spontaneous fractures shows significant differences in the spatial variation of the nonreducible:reducible collagen cross-links at bone-forming trabecular surfaces compared with normal bone. Introduction: Although the role of BMC and bone mineral quality in determining fracture risk has been extensively studied, considerably less attention has been paid to the quality of collagen in fragile bone. Materials and Methods: In this study, the technique of Fourier transform infrared imaging (FTIRI) was used to determine the ratio of nonreducible:reducible cross-links, in 2- to 4-,m-thick sections, from human iliac crest biopsy specimens (N = 27) at bone-forming trabecular surfaces. The biopsy specimens were obtained from patients that had been diagnosed as high- or low-turnover osteoporosis, as well as premenopausal women <40 years of age, with normal BMD and biochemistry, who suffered multiple spontaneous fractures. The obtained values were compared with previously published analyses of trabecular bone from normal non-osteoporotic subjects (N = 14, 6 males and 8 females; age range, 51,70 years). Results and Conclusions: Collagen cross-links distribution within the first 50 ,m at forming trabecular surfaces in patients with fragile bone was markedly different compared with normal bone. [source] Life-Cycle Assessment of Biosolids Processing OptionsJOURNAL OF INDUSTRIAL ECOLOGY, Issue 2 2001Gregory M. Peters Summary Biosolids, also known as sewage sludge, are reusable organic materials separated from sewage during treatment. They can be managed in a variety of ways. Different options for biosolids handling in Sydney, Australia, are compared in this study using life-cycle assessment. Two key comparisons are made: of system scenarios (scenario 1 is local dewatering and lime amendment; scenario 2 is a centralized drying system) and of technologies (thermal drying versus lime amendment). The environmental issues addressed are energy consumption, global warming potential (GWP), and human toxicity potential (HTP). Scenario 2 would consume 24% more energy than scenario 1. This is due to the additional electricity for pumping and particularly the petrochemical methane that supplements biogas in the drier. A centralized system using the same technologies as scenario 1 has approximately the same impacts. The GWP and HTP of the different scenarios do not differ significantly. The assessment of technology choices shows significant differences. The ample supply of endogenous biogas at North Head sewage treatment plant for the drying option allows reductions, relative to the lime-amendment option, of 68% in energy consumption, 45% in GWP, and 23% in HTP. Technology choices have more significant influence on the environmental profile of biosolids processing than does the choice of system configurations. Controlling variables for environmental improvement are the selection of biogas fuel, avoidance of coalsourced electrical energy, minimization of trucking distances, and raising the solids content of biosolids products. [source] In vitro transcription of PrfA-dependent and -independent genes of Listeria monocytogenesMOLECULAR MICROBIOLOGY, Issue 1 2001M. Lalic-Mülthaler In vitro transcription starting from the promoters of the Listeria monocytogenes genes hly, plcA, actA, mpl, prfA and iap has been studied. Whereas transcription from Phly, PplcA and PactA is strictly PrfA-dependent, that from Piap, PprfA1/2 and, unexpectedly, also from Pmpl is independent. Initiation of in vitro transcription at all tested promoters except PprfA requires high concentrations of ATP but not GTP. The nucleotides required in higher concentrations for efficient in vitro transcription are always included in the first three nucleotides of the corresponding transcript. RNA polymerase prepared from L. monocytogenes cultured either in rich culture medium (RNAPBHI), exposed to heat shock conditions (RNAP48) or conditioned in minimal essential medium (RNAPMEM) shows significant differences in the transcription efficiencies when transcription is initiated at these promoters. Transcription starting from the PrfA-dependent promoters PactA and Phly is enhanced with RNAP48 and RNAPMEM (in relation to Piap,mediated transcription), while transcription from the other promoters is reduced when compared with RNAPBHI. These data suggest that in vivo transcription of the genes actA and hly may not function optimally with RNA polymerase loaded with the vegetative sigma factor 43, but may require a modified RNA polymerase, possibly loaded with an alternative sigma factor. [source] Foliomena Fauna (Brachiopoda) from the Upper Ordovician of SardiniaPALAEONTOLOGY, Issue 2 2002E. Villas The late Ordovician brachiopod assemblage from Sardinia is one of the youngest members of the deep-water Foliomena fauna and is characterized by the following core taxa: Christiania, Cyclospira, Dedzetina and Foliomena. The fauna also contains Epitomyonia, Leangella, Glyptorthis and Skenidioides, which are more typical of shallower-water environments during the late Ordovician but occupied deeper-water niches during the Silurian following the termination of the Foliomena fauna. The suprafamilial placement of the family Chrustenoporidae is discussed and the new species Dedzetina serpaglii and Leangella (Leangella) fecunda are established. In common with many mid-Ashgill Foliomena faunas the Sardinian assemblage shows significant differences from other faunal developments of this type, reflecting its geographical position and shallower water conditions than those of the classic early Ashgill Foliomena faunas. The brachiopods occur with abundant trilobites belonging to a variant of the cyclopygid fauna. The faunas developed on part of a complex of microcontinents derived from peri-Gondwana during the Ordovician. [source] PRNP haplotype distribution in Moroccan goatsANIMAL GENETICS, Issue 4 2009C. Serrano Summary Susceptibility/resistance to scrapie in sheep and goats is influenced by host prion protein gene (PRNP) genotype. In this study, we report the analysis of prion protein gene polymorphisms in 137 goats of two Moroccan populations: D'man and Chaouni. We found seven previously described amino acid polymorphisms at codons 37, 127, 137, 142, 154, 222 and 240, as well as three known silent mutations. In addition, we identified three new allelic variants: 101R and 139S in D'man goats and 145D in D'man and Chaouni individuals. The high frequency of the resistant allele 154H could offer genetic protection against the disease to the analysed animals. A total of 12 haplotypes and 28 genotypes were found, the distribution of which shows significant differences between both groups. Moreover, haplotype frequencies were compared with bibliographic data showing that the haplotype distribution of PRNP in Moroccan populations is genetically similar to Southern Italian and Greek goats. [source] A high-resolution structure of ligand-free human glutamate carboxypeptidase IIACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 3 2007Cyril Barinka Human glutamate carboxypeptidase II (GCPII; EC 3.4.17.21) is an established marker for prostate-cancer diagnosis as well as a candidate therapeutic target for the treatment of diverse pathologies that involve glutamatergic transmission. Structural data on GCPII are thus valuable for the design and optimization of GCPII-specific inhibitors and diagnostic probes. The currently available structure of ligand-free GCPII was refined to a resolution of 3.5,Å. This work reports the structure of the protein refined to 1.65,Å resolution, with crystallographic values of R = 0.207 and Rfree = 0.228. The new structure extends the resolution appreciably and the new model based on this data shows significant differences when compared with the previously published model. [source] Effects of Tea Plantations on Stream Invertebrates in a Global Biodiversity Hotspot in AfricaBIOTROPICA, Issue 4 2009Olly van Biervliet ABSTRACT Tropical stream ecosystems in montane forest watersheds are important centers of endemism and diversity and provide essential ecosystem services. These habitats are subject to a variety of stressors, including the conversion of adjacent terrestrial habitats from forest to agriculture, but the impacts of these anthropogenic effects are largely unknown because of the paucity of studies in these systems. In montane habitats in the wet tropics, large-scale cultivation of tea is common and can represent an important source of income at local and national scales. However, little is known about how tea cultivation impacts adjacent stream ecosystems. In this study, we examine stream macroinvertebrate assemblages in a biodiversity hotspot the East Usambara Mountains, Tanzania. Specifically, we compare diversity of macroinvertebrate assemblages found on cobbles in stream riffles in watersheds dominated by forest with those surrounded by tea cultivation. We found that streams surrounded by tea were characterized by significantly lower dissolved oxygen and had lower total estimated species richness and number of families. Furthermore, the richness of invertebrate taxa known to be sensitive to anthropogenic disturbance were substantially reduced in tea streams and general assemblage-level analysis shows significant differences in the composition of macroinvertebrate assemblages between tea and forested streams. Our results suggest that tea cultivation may reduce stream habitat quality and biodiversity in the East Usambaras. Further research is needed to evaluate the effects of tea cultivation on streams over longer times scales and to address methods for minimizing negative effects of agriculture on montane stream communities. [source] | ||||||||||||||||