376 research outputs found
The Radon Signed Cumulative Distribution Transform and its applications in classification of Signed Images
Here we describe a new image representation technique based on the
mathematics of transport and optimal transport. The method relies on the
combination of the well-known Radon transform for images and a recent signal
representation method called the Signed Cumulative Distribution Transform. The
newly proposed method generalizes previous transport-related image
representation methods to arbitrary functions (images), and thus can be used in
more applications. We describe the new transform, and some of its mathematical
properties and demonstrate its ability to partition image classes with real and
simulated data. In comparison to existing transport transform methods, as well
as deep learning-based classification methods, the new transform more
accurately represents the information content of signed images, and thus can be
used to obtain higher classification accuracies. The implementation of the
proposed method in Python language is integrated as a part of the software
package PyTransKit, available on Github
Roles for Treg expansion and HMGB1 signaling through the TLR1-2-6 axis in determining the magnitude of the antigen-specific immune response to MVA85A
© 2013 Matsumiya et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are creditedA better understanding of the relationships between vaccine, immunogenicity and protection from disease would greatly facilitate vaccine development. Modified vaccinia virus Ankara expressing antigen 85A (MVA85A) is a novel tuberculosis vaccine candidate designed to enhance responses induced by BCG. Antigen-specific interferon-γ (IFN-γ) production is greatly enhanced by MVA85A, however the variability between healthy individuals is extensive. In this study we have sought to characterize the early changes in gene expression in humans following vaccination with MVA85A and relate these to long-term immunogenicity. Two days post-vaccination, MVA85A induces a strong interferon and inflammatory response. Separating volunteers into high and low responders on the basis of T cell responses to 85A peptides measured during the trial, an expansion of circulating CD4+ CD25+ Foxp3+ cells is seen in low but not high responders. Additionally, high levels of Toll-like Receptor (TLR) 1 on day of vaccination are associated with an increased response to antigen 85A. In a classification model, combined expression levels of TLR1, TICAM2 and CD14 on day of vaccination and CTLA4 and IL2Rα two days post-vaccination can classify high and low responders with over 80% accuracy. Furthermore, administering MVA85A in mice with anti-TLR2 antibodies may abrogate high responses, and neutralising antibodies to TLRs 1, 2 or 6 or HMGB1 decrease CXCL2 production during in vitro stimulation with MVA85A. HMGB1 is released into the supernatant following atimulation with MVA85A and we propose this signal may be the trigger activating the TLR pathway. This study suggests an important role for an endogenous ligand in innate sensing of MVA and demonstrates the importance of pattern recognition receptors and regulatory T cell responses in determining the magnitude of the antigen specific immune response to vaccination with MVA85A in humans.This work was funded by the Wellcome Trust. MM has a Wellcome Trust PhD studentship and HM is a Wellcome Trust Senior Fello
Routine gastric residual volume measurement to guide enteral feeding in mechanically ventilated infants and children : the GASTRIC feasibility study
Background
The routine measurement of gastric residual volume to guide the initiation and delivery of enteral feeding, is widespread in paediatric intensive care and neonatal units, but has little underlying evidence to support it.
Objective(s)
To answer the question: Is it feasible to conduct a trial of not measuring gastric residual volume on clinical outcomes in mechanically ventilated infants and children in the UK?
Design
A mixed methods study involving five linked work packages in two parallel arms, neonatal units and paediatric intensive care units. 1. A survey of units to establish current UK practice. 2. qualitative interviews with healthcare professionals and caregivers of children admitted to either setting. 3. A modified two-round e-Delphi survey to investigate health care professionals’ opinions on trial design issues and to obtain consensus on outcomes. 4. National databases were examined to determine the potential eligible populations. 5. Two consensus meetings, of health care professionals and parents to review the data and agreed consensus on outcomes that had not reached consensus in the e-Delphi.
Participants and setting
Parents of children with experience of ventilation and tube feeding in both neonatal units and in paediatric intensive care units, and health care professionals working in neonatal units and paediatric intensive care units.
Results
Baseline surveys showed the practice of gastric residual volume measurement was very common: 96% PICUs and 65% in neonatal units. Ninety percent of parents both from neonatal units and paediatric intensive care units supported a future trial, whilst highlighting concerns around possible delays in detecting complications. Health care professionals also indicated a trial was feasible, with 84% of staff willing to participate in a trial. Concerns expressed by junior nurses about the intervention arm of not measuring gastric residual volumes were addressed by developing a simple flowchart and education package. The trial design survey and e-Delphi study gained consensus on trial 12 PICU and 9 neonatal unit outcome measures and identified acceptable inclusion and exclusion criteria. Given the differences in physiology, disease processes, environments, staffing and outcomes of interest, two different trials are required in the two settings. Database analyses subsequently showed trials were feasible in both settings in terms of patient numbers. Of 16222 children who met the inclusion criteria in PICU 12 629 stayed > 3 days. In neonatal units, 15 375 neonates <32 weeks age. Finally, the two consensus meetings demonstrated ‘buy in’ from the wider UK neonatal communities and paediatric intensive care units and enabled us to discuss and vote on the outcomes that did not achieve consensus in the e-Delphi study.
Conclusions and future work
Two separate UK trials (one in neonatal units and one in paediatric intensive care units) are feasible to conduct, but they cannot be combined due to differences in outcome measures and treatment protocols, reflecting the distinctness of the two specialties
T-SPOT.TB responses during treatment of pulmonary tuberculosis
<p>Abstract</p> <p>Background</p> <p>Immune responses to <it>Mycobacterium tuberculosis </it>antigens could serve as surrogate markers of treatment response.</p> <p>Methods</p> <p>Using the T-SPOT.<it>TB </it>assay and frozen peripheral blood mononuclear cells, we enumerated ESAT-6- and CFP-10-specific IFN-γ-producing T cells over time in pulmonary TB patients receiving directly observed treatment. T cell responses (measured as "spot forming cells" or "SFCs") were assessed prior to treatment and at 16 and 24 weeks of treatment.</p> <p>Results</p> <p>58 patients were evaluated, of whom 57 were HIV seronegative. Mean (SD) ESAT-6, CFP-10, and summed RD1 specific SFCs declined from 42.7 (72.7), 41.2 (66.4), and 83.8 (105.7) at baseline to 23.3 (39.4, p = 0.01), 23.2 (29.4, p = 0.18), and 46.5 (59.5, p = 0.02) at completion of 24 weeks of treatment, respectively. Only 10% of individuals with a baseline reactive test reverted to negative at treatment week 24. For the group that was culture positive at completion of 8 weeks of treatment compared to the culture negative group, the incidence rate ratio (IRR) of ESAT-6, CFP-10, and summed RD1 specific SFC counts were, respectively, 2.23 (p = 0.048), 1.51 (p = 0.20), and 1.83 (p = 0.047). Patients with cavitary disease had mean ESAT-6 specific SFC counts that were higher than those without cavitary disease (IRR 2.08, p = 0.034).</p> <p>Conclusion</p> <p>IFN-γ-producing RD1-specific T cells, as measured in the T-SPOT.<it>TB </it>assay, may be directly related to bacterial load in patients undergoing treatment for pulmonary TB. However, high inter-subject variability in quantitative results coupled with failure of reversion to negative of qualitative results in most subjects at treatment completion may limit the utility of this assay as a surrogate marker for treatment efficacy.</p
Chromosome Bin Map of Expressed Sequence Tags in Homoeologous Group 1 of Hexaploid Wheat and Homoeology With Rice and Arabidopsis
A total of 944 expressed sequence tags (ESTs) generated 2212 EST loci mapped to homoeologous group 1 chromosomes in hexaploid wheat (Triticum aestivum L.). EST deletion maps and the consensus map of group 1 chromosomes were constructed to show EST distribution. EST loci were unevenly distributed among chromosomes 1A, 1B, and 1D with 660, 826, and 726, respectively. The number of EST loci was greater on the long arms than on the short arms for all three chromosomes. The distribution of ESTs along chromosome arms was nonrandom with EST clusters occurring in the distal regions of short arms and middle regions of long arms. Duplications of group 1 ESTs in other homoeologous groups occurred at a rate of 35.5%. Seventy-five percent of wheat chromosome 1 ESTs had significant matches with rice sequences (E ≤ e(−10)), where large regions of conservation occurred between wheat consensus chromosome 1 and rice chromosome 5 and between the proximal portion of the long arm of wheat consensus chromosome 1 and rice chromosome 10. Only 9.5% of group 1 ESTs showed significant matches to Arabidopsis genome sequences. The results presented are useful for gene mapping and evolutionary and comparative genomics of grasses
SELECTIVITY OF INSECTICIDES USED IN PEACH FARMING TO LARVAE OF Chrysoperla externa (NEUROPTERA: CHRYSOPIDAE) IN SEMI-FIELD CONDITIONS
The impact of circulating preeclampsia-associated extracellular vesicles on the migratory activity and phenotype of THP-1 monocytic cells
Intercellular communication via extracellular vesicles (EVs) and their target cells, especially immune cells, results in functional and phenotype changes that consequently may play a significant role in various physiological states and the pathogenesis of immune-mediated disorders. Monocytes are the most prominent environment-sensing immune cells in circulation, skilled to shape their microenvironments via cytokine secretion and further differentiation. Both the circulating monocyte subset distribution and the blood plasma EV pattern are characteristic for preeclampsia, a pregnancy induced immune-mediated hypertensive disorder. We hypothesized that preeclampsia-associated EVs (PE-EVs) induced functional and phenotypic alterations of monocytes. First, we proved EV binding and uptake by THP-1 cells. Cellular origin and protein cargo of circulating PE-EVs were characterized by flow cytometry and mass spectrometry. An altered phagocytosis-associated molecular pattern was found on 12.5 K fraction of PE-EVs: an elevated CD47 "don't eat me" signal (p < 0.01) and decreased exofacial phosphatidylserine "eat-me" signal (p < 0.001) were found along with decreased uptake of these PE-EVs (p < 0.05). The 12.5 K fraction of PE-EVs induced significantly lower chemotaxis (p < 0.01) and cell motility but accelerated cell adhesion of THP-1 cells (p < 0.05). The 12.5 K fraction of PE-EVs induced altered monocyte functions suggest that circulating EVs may have a role in the pathogenesis of preeclampsia
Performance of QuantiFERON-TB Gold In-Tube (QFTGIT) for the diagnosis of Mycobacterium tuberculosis (Mtb) infection in Afar Pastoralists, Ethiopia
<p>Abstract</p> <p>Background</p> <p>Currently, T-cell based gamma interferon (IFNγ) release assays (IGRAs) are acknowledged as the best methods available for the screening of latent tuberculosis infection (LTBI) and also as aid for the diagnosis of active tuberculosis (TB). To our information, the performance of these diagnostic tests has not been evaluated in Ethiopia. Therefore, the intent of this study was to evaluate the performance of QuantiFERON-TB Gold In-Tube (QFTGIT) in patients clinically suspected of active pulmonary TB (PTB) as well as in healthy subjects prior to its utilization for the epidemiological study of active TB and LTBI in Afar pastoralists.</p> <p>Methods</p> <p>The sensitivity of QFTGIT was evaluated in 140 subjects who were clinically suspected of PTB using the cut-off value recommended by the manufacturer (≥ 0.35 IU/ml) and disease-specific cut-off value. Sputum culture result was used as a gold standard. The specificity of the test was evaluated both in patients and in 55 tuberculin skin test (TST) negative healthy subjects.</p> <p>Results</p> <p>Out of the 140 study participants, 37 (26.4%) were positive for active PTB by culture. Out of the 37 subjects who had positive results by culture, 6 individuals were HIV-seropositive. Out of the 103 subjects who were negative by culture, 6 subjects had indeterminate results and 21 were HIV-seropositive. The performance of the test was assessed using data from 107 (31 culture positive and 76 culture negative) individuals who were clinically suspected of PTB and HIV-seronegatives. Using the manufacturer recommended cut-off value, the sensitivity of the test was 64.5% (20/31), while its specificity was 36.8% (28/76). The sensitivity of the test was increased to 77.4%, while the specificity was reduced to 23.7% using a cut-off value ≥ 0.1 IU/ml of IFNγ as disease-specific cut-off value. In TST negative healthy subjects, the specificity of the test was 58.2%.</p> <p>Conclusion</p> <p>Our findings revealed a low sensitivity of QFTGIT in the diagnosis of <it>Mycobacterium tuberculosis (Mtb) </it>infection in the present study area using the cut-off value recommended by the manufacturer. Nevertheless, the sensitivity increased from 64.5% to 77.4% by lowering the cut-off value recommended by the manufacturer to ≥ 0.1 IU/ml of IFNγ level. Hence, it is of practical importance to evaluate the performance of QFTGIT in population under different settings prior to its application either for the diagnosis of active TB or LTBI.</p
Fungal diversity associated to the olive moth, prays oleae Bernard : a survey for potential entomopathogenic fungi
Olive production is one of the main agricultural activities in Portugal. In the region of Trás-os-Montes this crop has been considerably affected by Prays oleae. In order to evaluate the diversity of fungi on P. oleae population of Trás-os-Montes olive orchards, larvae and pupae of the three annual generations (phyllophagous, antophagous and carpophagous) were collected and evaluated for fungal growth on their surface. From the 3828 larvae and pupae, a high percentage of individuals exhibited growth of a fungal agent (40.6%), particularly those from the phyllophagous generation. From all the moth generations, a total of 43 species from 24 genera were identified, but the diversity and abundance of fungal species differed between the three generations. Higher diversity was found in the carpophagous generation, followed by the antophagous and phyllophagous generations. The presence of fungi displaying entomopathogenic features was highest in the phyllophagous larvae and pupae, being B. bassiana the most abundant taxa. The first report of B. bassiana presence on P. oleae could open new strategies for the biocontrol of this major pest in olive groves, since the use of an already adapted species increases the guarantee of success of a biocontrol approach. The identification of antagonistic fungi able to control agents that cause major olive diseases, such as Verticillium dahliae, will benefit future biological control approaches for limiting this increasingly spreading pathogen.This work was supported by Science and Technology Foundation (Fundação para a Ciência e Tecnologia – FCT) project PTDC/AGR-AAM/102600/2008 “Entomopathogenic fungi associated to olive pests: isolation, characterization and selection for biological control”. The first author is grateful to the Science and Technology Foundation for the PhD grant SFRH/BD/44265/2008
Spectral characteristics of scintillations producing ionospheric irregularities in the Indian region
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