35,948 research outputs found
International forum. an investigation of iron status in blood donors
No abstract availabl
A Novel Real-Time Non-invasive Hemoglobin Level Detection Using Video Images from Smartphone Camera
Hemoglobin level detection is necessary for evaluating health condition in the human. In the laboratory setting, it is detected by shining light through a small volume of blood and using a colorimetric electronic particle counting algorithm. This invasive process requires time, blood specimens, laboratory equipment, and facilities. There are also many studies on non-invasive hemoglobin level detection. Existing solutions are expensive and require buying additional devices. In this paper, we present a smartphone-based non-invasive hemoglobin detection method. It uses the video images collected from the fingertip of a person. We hypothesized that there is a significant relation between the fingertip mini-video images and the hemoglobin level by laboratory gold standard. We also discussed other non-invasive methods and compared with our model. Finally, we described our findings and discussed future works
Systematic review: the diagnosis and staging of non-alcoholic fatty liver disease and non-alcoholic steatohepatitis.
Background: Non-alcoholic fatty liver disease (NAFLD) has become the most prevalent cause of liver disease in Western countries. The development of non-alcoholic steatohepatitis (NASH) and fibrosis identifies an at-risk group with increased risk of cardiovascular and liver-related deaths. The identification and management of this at-risk group remains a clinical challenge. \ud
\ud
Aim: To perform a systematic review of the established and emerging strategies for the diagnosis and staging of NAFLD. \ud
\ud
Methods: Relevant research and review articles were identified by searching PubMed, MEDLINE and EMBASE. \ud
Results: There has been a substantial development of non-invasive risk scores, biomarker panels and radiological modalities to identify at-risk patients with NAFLD without recourse to liver biopsy on a routine basis. These modalities and algorithms have improved significantly in their diagnosis and staging of fibrosis and NASH in patients with NAFLD, and will likely impact on the number of patients undergoing liver biopsy. \ud
\ud
Conclusions: Staging for NAFLD can now be performed by a combination of radiological and laboratory techniques, greatly reducing the requirement for invasive liver biopsy
Towards Picogram Detection of Superparamagnetic Iron-Oxide Particles Using a Gradiometric Receive Coil
Superparamagnetic iron-oxide nanoparticles can be used in a variety of
medical applications like vascular or targeted imaging. Magnetic particle
imaging (MPI) is a promising tomographic imaging technique that allows
visualizing the 3D nanoparticle distribution concentration in a non-invasive
manner. The two main strengths of MPI are high temporal resolution and high
sensitivity. While the first has been proven in the assessment of dynamic
processes like cardiac imaging, it is unknown how far the detection limit of
MPI can be lowered. Within this work, we will present a highly sensitive
gradiometric receive-coil unit combined with a noise-matching network tailored
for the measurement of mice. The setup is capable of detecting 5 ng of iron in
vitro at 2.14 sec acquisition time. In terms of iron concentration we are able
to detect 156 {\mu}g/L marking the lowest value that has been reported for an
MPI scanner so far. In vivo MPI mouse images of a 512 ng bolus at 21.5 ms
acquisition time allow for capturing the flow of an intravenously injected
tracer through the heart of a mouse. Since it has been rather difficult to
compare detection limits across MPI publications we propose guidelines
improving the comparability of future MPI studies.Comment: 15 Pages, 7 Figures, V2: Changed the initials of Author Kannan M
Krishnan, added two citations, corrected typo
MRI Tracking of Macrophages Labeled with Glucan Particles Entrapping a Water Insoluble Paramagnetic Gd-Based Agent.
PURPOSE: This study is aimed at demonstrating the in vivo potential of Gd(III)-loaded glucan particles (Gd-GPs) as magnetic resonance imaging (MRI)-positive agents for labeling and tracking phagocytic cells.
PROCEDURE: GPs were obtained from Saccharomyces cerevisae and loaded with the water-insoluble complex Gd-DOTAMA(C18)2. The uptake kinetics of Gd-GPs by murine macrophages was studied in vitro and the internalization mechanism was assessed by competition assays. The in vivo performance of Gd-GPs was tested at 7.05 T on a mouse model of acute liver inflammation.
RESULTS: The minimum number of Gd-GPs-labeled J774.A1 macrophages detected in vitro by MRI was ca. 300 cells/μl of agar, which is the lowest number ever reported for cells labeled with a positive T1 agent. Intravenous injection of macrophages labeled with Gd-GPs in a mouse model of liver inflammation enabled the MRI visualization of the cellular infiltration in the diseased area.
CONCLUSIONS: Gd-GPs represent a promising platform for tracking macrophages by MRI as a T1 alternative to the golden standard T2-based iron oxide particles
Aerospace Medicine and Biology: A continuing bibliography (supplement 229)
This bibliography lists 109 reports, articles, and other documents introduced into the NASA scientific and technical information system in January 1982
Toxicity of lunar dust
The formation, composition and physical properties of lunar dust are
incompletely characterised with regard to human health. While the physical and
chemical determinants of dust toxicity for materials such as asbestos, quartz,
volcanic ashes and urban particulate matter have been the focus of substantial
research efforts, lunar dust properties, and therefore lunar dust toxicity may
differ substantially. In this contribution, past and ongoing work on dust
toxicity is reviewed, and major knowledge gaps that prevent an accurate
assessment of lunar dust toxicity are identified. Finally, a range of studies
using ground-based, low-gravity, and in situ measurements is recommended to
address the identified knowledge gaps. Because none of the curated lunar
samples exist in a pristine state that preserves the surface reactive chemical
aspects thought to be present on the lunar surface, studies using this material
carry with them considerable uncertainty in terms of fidelity. As a
consequence, in situ data on lunar dust properties will be required to provide
ground truth for ground-based studies quantifying the toxicity of dust exposure
and the associated health risks during future manned lunar missions.Comment: 62 pages, 9 figures, 2 tables, accepted for publication in Planetary
and Space Scienc
Proteomic variation and diversity in clinical Streptococcus pneumoniae isolates from invasive and non-invasive sites
Mustapha Bittaye is a PhD student funded by the Medical Research Council Unit, The Gambia. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewedPublisher PD
Studies on the release of neutrophil extracellular traps and IFN-γ as part of the innate immune response to Aspergillus fumigatus and on the fungal stress response via the hybrid sensor kinase TcsC
Aspergillus fumigatus is a saprophytic mold that naturally inhabits the soil. Asexual reproduction yields hardy conidia that circulate in the air and are inhaled daily by humans. The fungus seems not to have evolved distinct mechanisms of pathogenicity, but is capable of responding to many stressful environmental cues present in its naturally harsh niche. The robust conidia present no problem to a fully functioning immune system, but if the innate immune system is compromised, the conidia can become activated and differentiate within the lung tissue to form invasive and disseminating hyphae. The resulting disease is called aspergillosis and is difficult to detect and to treat. To date, scientists have yet to find the factor(s) missing during immunosuppression that allow a healthy patient to easily dispose of A. fumigatus. We explored two possibilities: the production of neutrophil extracellular traps (NETs) and the release of IFN-γ by natural killer (NK) cells. We report here that NETs alone cannot kill the fungus, but do inhibit polar growth. Elongation of hyphal tips is abrogated due to zinc starvation, likely a consequence of the zinc-chelating, NETs-associated protein calprotectin. NK cells alone are also incapable of fungicidal activity, but their release of IFN-γ upon contact with A. fumigatus abrogates hyphal growth by a yet unknown mechanism. In vitro studies of the innate immune response, though helpful, are far from representative of the in vivo response. Neither NETs nor IFN-γ alone can manage Aspergillus infection, but in combination, these and other immune assaults certainly can. The difficulty lies in identifying the precise combination of immune cells and cytokine milieu that in a healthy individual prevent infection.
Additionally, we explored mechanisms by which the fungus responds to stress, namely the HOG MAPK pathway, historically involved in osmotic stress response. In filamentous fungi, certain stress signals are sensed by a cytoplasmic hybrid histidine kinase sensor and then passed through the HOG system via phosphorylation. We identified the putative hybrid sensor kinase in A. fumigatus, and generated a corresponding knockout mutant. The ΔtcsC mutant was indeed sensitive to osmotic stress, and resistant to the phenolpyrrole fungicide fludioxonil. In the wild type the addition of either osmotic stress or fludioxonil resulted in SakA phosphorylation and translocation to the nucleus. SakA, the Hog1 homolog in A. fumigatus, is located at the end of the HOG pathway, confirming the role of TcsC as the cytoplasmic sensor upstream of SakA. In hypoxia, on farnesol, and in high concentrations of divalent cations the ΔtcsC mutant exhibited a striking “fluffy” phenotype characterized by the production of tremendous aerial hyphae and little or no differentiation, i.e., no conidiation. Though the ΔtcsC mutant showed no change in virulence compared to wild type, components of the TcsC signalling pathway remain promising targets for antifungal agents
- …