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531.
Bonifati V Rizzu P van Baren MJ Schaap O Breedveld GJ Krieger E Dekker MC Squitieri F Ibanez P Joosse M van Dongen JW Vanacore N van Swieten JC Brice A Meco G van Duijn CM Oostra BA Heutink P 《Science (New York, N.Y.)》2003,299(5604):256-259
The DJ-1 gene encodes a ubiquitous, highly conserved protein. Here, we show that DJ-1 mutations are associated with PARK7, a monogenic form of human parkinsonism. The function of the DJ-1 protein remains unknown, but evidence suggests its involvement in the oxidative stress response. Our findings indicate that loss of DJ-1 function leads to neurodegeneration. Elucidating the physiological role of DJ-1 protein may promote understanding of the mechanisms of brain neuronal maintenance and pathogenesis of Parkinson's disease. 相似文献
532.
Carmen Arena Anna De Maio Flavia De Nicola Lucia Santorufo Luca Vitale Giulia Maisto 《Water, air, and soil pollution》2014,225(1):1-12
Bioretention cells, also known as raingardens, are increasingly being constructed as a means to collect, infiltrate, and treat stormwater runoff. There are concerns, however, about how stormwater management practices might function in terms of infiltration and pollutant removal as they age. Saturated hydraulic conductivity (K sat) values were obtained for eight cells in 2006 and again for three of those cells in 2010 using an infiltrometer. A strong positive correlation of mean K sat with service time was observed (slope = 10.2?±?2.4 cm/h per year, R 2 = 0.67). Results from metals analyses of bioretention media cores collected from six bioretention cells showed the expected trend of Cu and Zn enrichment at the surface while Cd was detected only in one out of 72 media samples analyzed. Sorption isotherms from batch testing of field media samples (T = 22.5 °C, pH = 7.2) were used to estimate metal sorption capacities based on representative stormwater Cd and Zn concentrations. Cu was not considered, as very little of the metal is dissolved under these conditions (22.8?±?7.1 %). The mean equilibrium sorption capacities for Cd (10.2?±?3.1 mg/kg) and Zn (294.9?±?14.9 mg/kg) far exceeded observed levels in the bioretention media such that the remaining sorption capacity was ≥83 % for Zn and ≥90 % for Cd for the cells. Overall, the results of this investigation suggest that bioretention cells can provide many years of effective infiltration (>6 years) and metals removal performance (>25 years). 相似文献
533.
Andreina Traversa Elisabetta Loffredo Concetta E. Gattullo Antonio J. Palazzo Terry L. Bashore Nicola Senesi 《Journal of Soils and Sediments》2014,14(2):432-440
Purpose
This study aimed to investigate comparatively the main chemical and physico-chemical properties of the humic acid (HA) fraction of three different composts and to evaluate the bioactive effects of these HAs on the germination and early growth of four populations of switchgrass.Materials and methods
Three compost HAs isolated from a green compost (HAGC), a mixed compost (HAMC), and a coffee compost (HACC) were characterized for some chemical and physico-chemical properties, such as ash content, elemental composition, total acidity, carboxylic and phenolic OH group contents, E4/E6 ratio, Fourier Transform infrared (FT IR), and fluorescence spectroscopies. In subsequent experiments conducted in vitro in a climatic chamber under controlled conditions, the bioactive effects of the three HAs at concentrations of 10, 50, and 200 mg?L?1 were tested on the germination and early growth of four switchgrass (Panicum virgatum L.) populations, the octaploids Shelter, Shawnee and Dacotah, and the tetraploid Alamo.Results and discussion
The ash content and the E4/E6 ratio were, respectively, much higher or slightly higher for HACC than for the other two HAs. HAMC showed the lowest C and H contents and the highest O content, whereas HAGC had the highest N content. The total acidity and phenolic OH group content followed the order: HAMC?>?HACC?>?HAGC. The fluorescence analysis of the three HAs evidenced a common fluorophore unit possibly associated to simple aromatic structures, such as phenolic-like, hydroxy-substituted benzoic and cinnamic acid derivatives. The FT IR spectra of all HA samples indicated the presence of aromatic phenolic structures. Significant beneficial effects were produced by any HA on switchgrass germination and early growth as a function of the population tested and the HA dose.Conclusions
Results of this study demonstrated that the addition of compost HAs to the germination medium of four switchgrass populations positively influenced the germination process and the growth of primary root and shoot. Significant correlations were found between HA bioactivity and some HA properties. These results suggest a possible use of compost as soil amendment in areas where switchgrass grows naturally or is cultivated. 相似文献534.
Mammalian mitochondrial DNA (mtDNA) replication has long been considered to occur by asymmetric synthesis of the two strands, starting at the multiple origins of the strand-displacement loop (D-loop). We report the discovery of a major replication origin at position 57 in the D-loop of several human cell lines (HeLa, A549, and 143B.TK-) and immortalized lymphocytes. The nascent chains starting at this origin, in contrast to those initiated at the previously described origins, do not terminate prematurely at the 3' end of the D-loop but proceed well beyond this control point, behaving as "true" replicating strands. This origin is mainly responsible for mtDNA maintenance under steady-state conditions, whereas mtDNA synthesis from the formerly identified D-loop origins may be more important for recovery after mtDNA depletion and for accelerating mtDNA replication in response to physiological demands. 相似文献
535.
P?John?D?LambsheadEmail author Caroline?J?Brown Timothy?J?Ferrero Lawrence?E?Hawkins Craig?R?Smith Nicola?J?Mitchell 《BMC ecology》2003,3(1):1
Background
The possibility for commercial mining of deep-sea manganese nodules is currently under exploration in the abyssal Clarion-Clipperton Fracture Zone. Nematodes have potential for biomonitoring of the impact of commercial activity but the natural biodiversity is unknown. We investigate the feasibility of nematodes as biomonitoring organisms and give information about their natural biodiversity.Results
The taxonomic composition (at family to genus level) of the nematode fauna in the abyssal Pacific is similar, but not identical to, the North Atlantic. Given the immature state of marine nematode taxonomy, it is not possible to comment on the commonality or otherwise of species between oceans. The between basin differences do not appear to be directly linked to current ecological factors. The abyssal Pacific region (including the Fracture Zone) could be divided into two biodiversity subregions that conform to variations in the linked factors of flux to the benthos and of sedimentary characteristics. Richer biodiversity is associated with areas of known phytodetritus input and higher organic-carbon flux. Despite high reported sample diversity, estimated regional diversity is less than 400 species.Conclusion
The estimated regional diversity of the CCFZ is a tractable figure for biomonitoring of commercial activities in this region using marine nematodes, despite the immature taxonomy (i.e. most marine species have not been described) of the group. However, nematode ecology is in dire need of further study.536.
Ruhl S Casson N Kaiser C Thoma R Pospischil A Greub G Borel N 《Veterinary microbiology》2009,135(1-2):169-174
Bovine abortion of unknown infectious aetiology still remains a major economic problem. In this study, we focused on a new possible abortigenic agent called Parachlamydia acanthamoebae. Retrospective samples (n=235) taken from late-term abortions in cattle were investigated by real-time diagnostic PCR for Chlamydiaceae and Parachlamydia spp., respectively. Histological sections of cases positive by real-time PCR for any Chlamydia-related agent were further examined by immunohistochemistry using specific antibodies. Chlamydophila abortus was detected only in three cases (1.3%) by real-time PCR and ArrayTube Microarray playing a less important role in bovine abortion compared to the situation in small ruminants in Switzerland. By real-time PCR as many as 43 of 235 (18.3%) cases turned out to be positive for Parachlamydia. The presence of Parachlamydia within placental lesions was confirmed in 35 cases (81.4%) by immunohistochemistry. The main histopathological feature in parachlamydial abortion was purulent to necrotizing placentitis (25/43). Parachlamydia should be considered as a new abortigenic agent in Swiss cattle. Since Parachlamydia may be involved in lower respiratory tract infections in humans, bovine abortion material should be handled with care given the possible zoonotic risk. 相似文献
537.
This study was performed to ascertain whether a standardized extract from Echinacea angustifolia (Polinacea™) affects proliferation and interferon gamma (IFN-γ) secretion in bovine peripheral blood mononuclear cells (PBMC).PBMC from six Holstein heifers were incubated with 0, 6.3, 20, 60, or 180 μg/ml of the tested compound. Proliferation was stimulated by concanavalin A (ConA) or pokeweed-mitogen (PWM). Secretion of IFN-γ was stimulated by ConA.All concentrations of Polinacea™ exerted a mitogenic effect. With respect to control PBMC (0 μg/ml), the lowest and highest increase of proliferation were observed with Polinacea™ at 6.3 (2-fold increase) or 180 (10-fold increase) μg/ml, respectively. Polinacea™ at 180 μg/ml reduced ConA-driven proliferation, whereas at 20 and 60 μg/ml improved proliferation of PWM-stimulated PBMC. IFN-γ secretion was not affected. In conclusion, Polinacea™ modulates bovine PBMC proliferation, and deserves to be tested in vivo to define conditions that may benefit from its utilization. 相似文献
538.
539.
Daniele Zaccaria Nicola Lamaddalena Christopher M. U. Neale Gary P. Merkley Nicola Palmisano Giuseppe Passarella 《Irrigation Science》2013,31(3):209-224
This study describes a model named HydroGEN that was conceived for simulating hydrographs of daily volumes and hourly flow rates during peak-demand periods in pressurized irrigation delivery networks with on-demand operation. The model is based on a methodology consisting of deterministic and stochastic components and is composed of a set of input parameters to reproduce the crop irrigation management practices followed by farmers and of computational procedures enabling to simulate the soil water balance and the irrigation events for all cropped fields supplied by each delivery hydrant in a distribution network. The input data include values of weather, crop, and soil parameters, as well as information on irrigation practices followed by local farmers. The resulting model outputs are generated flow hydrographs during the peak-demand period, which allow the subsequent analysis of performance achievable under different delivery scenarios. The model can be applied either for system design or re-design, as well as for analysis of operation and evaluation of performance achievements of on-demand pressurized irrigation delivery networks. Results from application of HydroGEN to a real pressurized irrigation system at different scales are presented in a companion paper (Part II: model applications). 相似文献
540.
The northwest of Scotland is a stronghold for two of the UK’s rarest bumblebee species, Bombus distinguendus and Bombus muscorum. The predominant form of agricultural land management in this region is crofting, a system specific to Scotland in which small agricultural units (crofts) operate rotational cropping and grazing regimes. Crofting is considered to be beneficial to a wide range of flora and fauna. However, currently there is a lack of quantitative evidence to support this view with regard to bumblebee populations. In this study we assessed the effect of land management on the abundance of foraging bumblebees and the availability of bumblebee forage plants across crofts in northwest Scotland. The results of our study show that current crofting practices do not support high densities of foraging bumblebees. Traditional crofting practice was to move livestock to uplands in the summer, but this has been largely abandoned. Summer sheep grazing of lowland pasture had a strong negative impact on bumblebee abundance and forage plant availability throughout the survey period. The use of specific ‘bird and bee’ conservation seed mixes appears to improve forage availability within the crofted landscape, although the number of bees observed remained low. Of the forage plants available, the three most frequently visited species were from the Fabaceae. We therefore conclude that the creation of agri-environment schemes which promote the use of Fabaceae-rich seed mixes and encourage the removal of sheep grazing on lowland areas throughout the summer are essential in order to conserve bumblebee populations within crofted areas. 相似文献