A multicenter clinical study was conducted to evaluate the performance characteristics of the Abbott RealTime CT/NG assay, a multiplex real-time PCR assay, for simultaneous detection of Chlamydia ...trachomatis and Neisseria gonorrhoeae. The specimens were collected from a total of 3,832 male and female subjects at 16 geographically diverse sites. Specimens included male and female urine samples, male urethral swabs, female endocervical swabs, and self-collected and clinician-collected vaginal swabs. Specimens were tested with the automated Abbott RealTime CT/NG assay, Aptima Combo 2 assay (Gen-Probe), ProbeTec ET CT/GC assay (Becton Dickinson), and culture for N. gonorrhoeae. The Aptima Combo 2 assay, the ProbeTec assay, and the N. gonorrhoeae culture were used as the reference assays. For each subject, a patient infected status (PIS) was determined based on the combined results from the reference assays. The overall prevalence in female subjects was 8.9% for C. trachomatis and 3.8% for N. gonorrhoeae. The overall male prevalence was 18.2% for C. trachomatis and 16.7% for N. gonorrhoeae. The overall sensitivity and specificity of the Abbott RealTime CT/NG assay were 92.4% and 99.2% for C. trachomatis and 96.9% and 99.7% for N. gonorrhoeae, respectively. In comparison, the sensitivity and specificity, respectively, for the Aptima Combo 2 assay were 94.5% and 99.0% for C. trachomatis and 96.1% and 99.5% for N. gonorrhoeae, and those for the ProbeTec ET assay were 90.3% and 99.5% for C. trachomatis and 92.0% and 97.3% for N. gonorrhoeae in this study. The Abbott RealTime CT/NG assay offers C. trachomatis and N. gonorrhoeae dual detection with high sensitivity and specificity. The automated assay provides a useful alternative nucleic acid amplification assay for clinical laboratories and clinicians.
Two lines of evidence indicate that there exists a reciprocal inhibitory relationship between opposed brain networks. First, most attention-demanding cognitive tasks activate a stereotypical set of ...brain areas, known as the task-positive network and simultaneously deactivate a different set of brain regions, commonly referred to as the task negative or default mode network. Second, functional connectivity analyses show that these same opposed networks are anti-correlated in the resting state. We hypothesize that these reciprocally inhibitory effects reflect two incompatible cognitive modes, each of which may be directed towards understanding the external world. Thus, engaging one mode activates one set of regions and suppresses activity in the other. We test this hypothesis by identifying two types of problem-solving task which, on the basis of prior work, have been consistently associated with the task positive and task negative regions: tasks requiring social cognition, i.e., reasoning about the mental states of other persons, and tasks requiring physical cognition, i.e., reasoning about the causal/mechanical properties of inanimate objects. Social and mechanical reasoning tasks were presented to neurologically normal participants during fMRI. Each task type was presented using both text and video clips. Regardless of presentation modality, we observed clear evidence of reciprocal suppression: social tasks deactivated regions associated with mechanical reasoning and mechanical tasks deactivated regions associated with social reasoning. These findings are not explained by self-referential processes, task engagement, mental simulation, mental time travel or external vs. internal attention, all factors previously hypothesized to explain default mode network activity. Analyses of resting state data revealed a close match between the regions our tasks identified as reciprocally inhibitory and regions of maximal anti-correlation in the resting state. These results indicate the reciprocal inhibition is not attributable to constraints inherent in the tasks, but is neural in origin. Hence, there is a physiological constraint on our ability to simultaneously engage two distinct cognitive modes. Further work is needed to more precisely characterize these opposing cognitive domains.
► Physical reasoning tasks activate the TPN and deactivate the DMN. ► Social reasoning tasks deactivate the TPN and activate the DMN. ► Activated/deactivated regions match areas of maximal anti-correlation. ► Findings are not explained by task engagement, or internal vs. external attention. ► TPN versus DMN dichotomy reflects opposing cognitive modes.
Hippocampal volume is a marker of brain health and is reduced with aging and neurological disease. Exercise may be effective at increasing and preserving hippocampal volume, potentially serving as a ...treatment for conditions associated with hippocampal atrophy (e.g., dementia). This meta‐analysis aimed to identify whether exercise training has a positive effect on hippocampal volume and how population characteristics and exercise parameters moderate this effect. Studies met the following criteria: (a) controlled trials; (b) interventions of physical exercise; (c) included at least one time‐point of hippocampal volume data before the intervention and one after; (d) assessed hippocampal volume using either manual or automated segmentation algorithms. Animal studies, voxel‐based morphometry analyses, and multi‐modal interventions (e.g., cognitive training or meditation) were excluded. The primary analysis in n = 23 interventions from 22 published studies revealed a significant positive effect of exercise on total hippocampal volume. The overall effect was significant in older samples (65 years of age or older) and in interventions that lasted over 24 weeks and had less than 150 min per week of exercise. These findings suggest that moderate amounts of exercise for interventions greater than 6 months have a positive effect on hippocampal volume including in older populations vulnerable to hippocampal atrophy.
Experiences from Nordic countries and Canada have shown that the retrieval of the stem volume and mean tree height of a tree or at stand level from laser scanner data performs as well as, or better ...than, photogrammetric methods, and better than other remote sensing methods. This paper reviews the methods of small-footprint airborne laser scanning for extracting forest inventory data, mainly in the boreal forest zone. The methods are divided into the following categories: extraction of terrain and canopy height model; feature extraction approaches (canopy height distribution and individual-tree-based techniques, techniques based on the synergetic use of aerial images and lidar, and other new approaches); tree species classification and forest growth using laser scanner; and the use of intensity and waveform data in forest information extraction. Despite this, the focus is on methods, some review of quality obtained, especially in the boreal forest area, is included. Several recommendations for future research are given to foster the methodology development.
Background. Kidney retransplants carry increased immunologic risk. One possible contributor to this risk may be re-exposure to human leukocyte antigens (HLA) common to a previous donor but foreign to ...the recipient. Conflicting publications have assessed this risk, so to examine our experience 259 kidney retransplants were analyzed. Methods. A retrospective cohort of retransplant patients from 1973 to 2005 with minimum 12 months follow up was examined. Using multivariable modeling, important confounders were controlled for identifying factors significantly affecting graft survival. Results. Re-exposure to HLA class I (HLA-A or B) antigens, peak panel reactive antibodies and donor source were the most important determinants of allograft survival, despite a negative conventional or anti-human globulin-augmented T cell crossmatch. We failed to demonstrate that recipient re-exposure to HLA class II (HLA-DR) or positive B cell crossmatch were associated with adverse outcomes. Sample size and molecular versus serologic methods may have influenced the former, while inability to determine antibody specificities may have influenced the latter. Controlling for other variables, the adjusted risk of graft loss associated with re-exposure to HLA class I increased by 71% (P=0.006) and occurred early, consistent with recall of memory cytotoxic T lymphocyte or antibody responses. Conclusions. Kidney recipients re-exposed to mismatched HLA class I antigens appear to be at heightened risk of early graft loss. Such patients may benefit from pretransplant identification of donor specific antibodies using solid phase methods and heightened vigilance for acute rejection. Future studies may indicate whether more intensive immunosuppression for these patients is warranted.
This study investigates the potential impacts of future climate and socio-economic change on the flow and nitrogen fluxes of the Ganga river system. This is the first basin scale water quality study ...for the Ganga considering climate change at 25 km resolution together with socio-economic scenarios. The revised dynamic, process-based INCA model was used to simulate hydrology and water quality within the complex multi-branched river basins. All climate realizations utilized in the study predict increases in temperature and rainfall by the 2050s with significant increase by the 2090s. These changes generate associated increases in monsoon flows and increased availability of water for groundwater recharge and irrigation, but also more frequent flooding. Decreased concentrations of nitrate and ammonia are expected due to increased dilution. Different future socio-economic scenarios were found to have a significant impact on water quality at the downstream end of the Ganga. A less sustainable future resulted in a deterioration of water quality due to the pressures from higher population growth, land use change, increased sewage treatment discharges, enhanced atmospheric nitrogen deposition, and water abstraction. However, water quality was found to improve under a more sustainable strategy as envisaged in the Ganga clean-up plan.
This study investigates the potential impacts of future climate and socio-economic change on the flow and nitrogen fluxes of the Ganga river system.
Canada's managed boreal forest, 54% of the nation's total boreal forest area, stores 28 Pg carbon (C) in biomass, dead organic matter, and soil pools. The net C balance is dominated by the difference ...of two large continuous fluxes: C uptake (net primary production) and release during decomposition (heterotrophic respiration). Additional releases of C can be high in years, or in areas, that experience large anthropogenic or natural disturbances. From 1990 to 2008, Canada's managed boreal forest has acted as C sink of 28 Tg C year−1, removing CO2from the atmosphere to replace the 17 Tg of C annually harvested and store an additional 11 Tg of C year−1in ecosystem C pools. A large fraction (57%) of the C harvested since 1990 remains stored in wood products and solid waste disposal sites in Canada and abroad, replacing C emitted from the decay or burning of wood harvested prior to 1990 and contributing to net increases in product and landfill C pools. Wood product use has reduced emissions in other sectors by substituting for emission-intensive products (concrete, steel). The C balance of the unmanaged boreal forest is currently unknown. The future C balance of the Canadian boreal forest will affect the global atmospheric C budget and influence the mitigation efforts required to attain atmosphericCO2stabilization targets. The single biggest threat toCstocks is human-caused climate change. LargeCstocks have accumulated in the boreal because decomposition is limited by cold temperatures and often anoxic environments. Increases in temperatures and disturbance rates could result in a large net C source during the remainder of this century and beyond. Uncertainties about the impacts of global change remain high, but we emphasize the asymmetry of risk: sustained large-scale increases in productivity are unlikely to be of sufficient magnitude to offset higher emissions from increased disturbances and heterotrophic respiration. Reducing the uncertainties of the current and future C balance of Canada's 270 Mha of boreal forest requires addressing gaps in monitoring, observation, and quantification of forest C dynamics, with particular attention to 125 Mha of unmanaged boreal forest with extensive areas of deep organic soils, peatlands, and permafrost containing large quantities of C that are vulnerable to global warming.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Exosomes are 60-100-nm membrane vesicles that are secreted into the extracellular milieu as a consequence of multivesicular body fusion with the plasma membrane. Here we determined the protein and ...lipid compositions of highly purified human B cell-derived exosomes. Mass spectrometric analysis indicated the abundant presence of major histocompatibility complex (MHC) class I and class II, heat shock cognate 70, heat shock protein 90, integrin alpha 4, CD45, moesin, tubulin (alpha and beta), actin, G(i)alpha(2), and a multitude of other proteins. An alpha 4-integrin may direct B cell-derived exosomes to follicular dendritic cells, which were described previously as potential target cells. Clathrin, heat shock cognate 70, and heat shock protein 90 may be involved in protein sorting at multivesicular bodies. Exosomes were also enriched in cholesterol, sphingomyelin, and ganglioside GM3, lipids that are typically enriched in detergent-resistant membranes. Most exosome-associated proteins, including MHC class II and tetraspanins, were insoluble in 3-(3-cholamidopropyl)dimethylammonio-1-propanesulfonic acid (CHAPS)-containing buffers. Multivesicular body-linked MHC class II was also resistant to CHAPS whereas plasma membrane-associated MHC class II was solubilized readily. Together, these data suggest that recruitment of membrane proteins from the limiting membranes into the internal vesicles of multivesicular bodies may involve their incorporation into tetraspanin-containing detergent-resistant membrane domains.
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