3,245 research outputs found
Cytokine polymorphisms in patients with autoimmune hemolytic anemia
Autoimmune hemolytic anemia (AIHA) is due to autoantibodies with or without complement activation and involves cellular and cytokine dysregulation. Here, we investigated cytokine single-nucleotide polymorphisms (SNPs) of TNF-α, TGF-β1, IL-10, IL-6, and IFN-γ, along with their serum levels. The former were related to hematological parameters, therapy, and clinical outcome. The study included 123 consecutive patients with primary AIHA [77 warm AIHA and 46 cold agglutinin disease (CAD)], followed up for a median of 49 months. Results show that the allelic frequency of TNF-α -308 G/A polymorphisms was significantly lower in patients versus controls. Moreover, the genotypic frequency of TNF-α -308G/A and TGF-β gene codon 25 G/C genotypes was significantly lower in patients versus controls. Considering cytokine SNP genotypes associated with different gene expression levels, TNF-α high gene expression was significantly more frequent in patients, TGF-β and IL-10 high gene expression was higher in patients with more severe anemia, and TGF-β high gene expression was higher in patients with active disease. Considering treatment, TNF-α and TGF-β high gene expression was more frequent in multitreated patients and particularly in CAD. It may be speculated that this genetic predisposition to a stronger inflammatory response may result in a greater immune dysregulation and in a relapsed/refractory disease. Regarding cytokine serum levels, TNF-α and TGF-β were significantly lower, and IL-10 and IL-6 were significantly higher in patients versus controls, underlying the complex interplay between genetic background and disease features
Stakeholder Perceptions of Point-of-Care Ultrasound Implementation in Resource-Limited Settings
Nearly half of the world lacks access to diagnostic imaging. Point of care ultrasound (POCUS) is a versatile and relatively affordable imaging modality that offers promise as a means of bridging the radiology gap and improving care in low resource settings. Methods: We performed semi-structured interviews of key stakeholders at two diverse hospitals where POCUS implementation programs had recently been conducted: one in a rural private hospital in Haiti and the other in a public referral hospital in Malawi. Questions regarding the clinical utility of POCUS, as well as barriers and facilitators of its implementation, were asked of study participants. Using the Framework Method, analysis of interview transcripts was guided by the WHO ASSURED criteria for point of care diagnostics. Results: Fifteen stakeholders with diverse roles in POCUS implementation were interviewed. Interviewees from both sites considered POCUS a valuable diagnostic tool that improved clinical decisions. They perceived barriers to adequate training as one of the most important remaining barriers to POCUS implementation. Conclusions: In spite of the increasing affordability and portability of ultrasounds devices, there are still important barriers to the implementation of POCUS in resource-limited settings
Stakeholder Perceptions of Point-of-Care Ultrasound Implementation in Resource-Limited Settings
Nearly half of the world lacks access to diagnostic imaging. Point of care ultrasound (POCUS) is a versatile and relatively affordable imaging modality that offers promise as a means of bridging the radiology gap and improving care in low resource settings. Methods: We performed semi-structured interviews of key stakeholders at two diverse hospitals where POCUS implementation programs had recently been conducted: one in a rural private hospital in Haiti and the other in a public referral hospital in Malawi. Questions regarding the clinical utility of POCUS, as well as barriers and facilitators of its implementation, were asked of study participants. Using the Framework Method, analysis of interview transcripts was guided by the WHO ASSURED criteria for point of care diagnostics. Results: Fifteen stakeholders with diverse roles in POCUS implementation were interviewed. Interviewees from both sites considered POCUS a valuable diagnostic tool that improved clinical decisions. They perceived barriers to adequate training as one of the most important remaining barriers to POCUS implementation. Conclusions: In spite of the increasing affordability and portability of ultrasounds devices, there are still important barriers to the implementation of POCUS in resource-limited settings
Non-equilibrium states of a photon cavity pumped by an atomic beam
We consider a beam of two-level randomly excited atoms that pass one-by-one
through a one-mode cavity. We show that in the case of an ideal cavity, i.e. no
leaking of photons from the cavity, the pumping by the beam leads to an
unlimited increase in the photon number in the cavity. We derive an expression
for the mean photon number for all times. Taking into account leaking of the
cavity, we prove that the mean photon number in the cavity stabilizes in time.
The limiting state of the cavity in this case exists and it is independent of
the initial state. We calculate the characteristic functional of this
non-quasi-free non-equilibrium state. We also calculate the energy flux in both
the ideal and open cavity and the entropy production for the ideal cavity.Comment: Corrected energy production calculations and made some changes to
ease the readin
Potentiation of Antibiofilm Activity of Amphotericin B by Superoxide Dismutase Inhibition
This study demonstrates a role for superoxide dismutases (Sods) in governing tolerance of Candida albicans biofilms to amphotericin B (AmB). Coincubation of C. albicans biofilms with AmB and the Sod inhibitors N,N′-diethyldithiocarbamate (DDC) or ammonium tetrathiomolybdate (ATM) resulted in reduced viable biofilm cells and increased intracellular reactive oxygen species levels as compared to incubation of biofilm cells with AmB, DDC, or ATM alone. Hence, Sod inhibitors can be used to potentiate the activity of AmB against C. albicans biofilms
Mitigating Errors on Superconducting Quantum Processors through Fuzzy Clustering
Quantum utility has been severely limited in superconducting quantum hardware
until now by the modest number of qubits and the relatively high level of
control and readout errors, due to the intentional coupling with the external
environment required for manipulation and readout of the qubit states.
Practical applications in the Noisy Intermediate Scale Quantum (NISQ) era rely
on Quantum Error Mitigation (QEM) techniques, which are able to improve the
accuracy of the expectation values of quantum observables by implementing
classical post-processing analysis from an ensemble of repeated noisy quantum
circuit runs. In this work, we focus on a recent QEM technique that uses Fuzzy
C-Means (FCM) clustering to specifically identify measurement error patterns.
For the first time, we report a proof-of-principle validation of the technique
on a 2-qubit register, obtained as a subset of a real NISQ 5-qubit
superconducting quantum processor based on transmon qubits. We demonstrate that
the FCM-based QEM technique allows for reasonable improvement of the
expectation values of single- and two-qubit gates based quantum circuits,
without necessarily invoking state-of-the-art coherence, gate, and readout
fidelities
Oxidative stress, metabolic and histopathological alterations in mussels exposed to remediated seawater by GO-PEI after contamination with mercury
The modern technology brought new engineering materials (e.g. nanostructured materials) with advantageous characteristics such as a high capacity to decontaminate water from pollutants (for example metal(loid)s). Among those innovative materials the synthesis of nanostructured materials (NSMs) based on graphene as graphene oxide (GO) functionalized with polyethyleneimine (GO-PEI) had a great success due to their metal removal capacity from water. However, research dedicated to environmental risks related to the application of these materials is still non-existent. To evaluate the impacts of such potential stressors, benthic species can be a good model as they are affected by several environmental constraints. Particularly, the mussel Mytilus galloprovincialis has been identified by several authors as a bioindicator that responds quickly to environmental disturbances, with a wide spatial distribution and economic relevance. Thus, the present study aimed to evaluate the impacts caused in M. galloprovincialis by seawater previously contaminated by Hg and decontaminated using GO-PEI. For this, histopathological and biochemical alterations were examined. This study demonstrated that mussels exposed to the contaminant (Hg), the decontaminant (GO-PEI) and the combination of both (Hg + GO-PEI) presented an increment of histopathological, oxidative stress and metabolic alterations if compared to organisms under remediated seawater and control conditions The present findings highlight the possibility to remediate seawater with nanoparticles for environmental safety purposes.publishe
Human coronary microvascular contractile dysfunction associates with viable synthetic smooth muscle cells
Aims
Coronary microvascular smooth muscle cells (SMCs) respond to luminal pressure by developing myogenic tone (MT), a process integral to the regulation of microvascular perfusion. The cellular mechanisms underlying poor myogenic reactivity in patients with heart valve disease are unknown and form the focus of this study.
Methods and results
Intramyocardial coronary micro-arteries (IMCAs) isolated from human and pig right atrial (RA) appendage and left ventricular (LV) biopsies were studied using pressure myography combined with confocal microscopy. All RA- and LV-IMCAs from organ donors and pigs developed circa 25% MT. In contrast, 44% of human RA-IMCAs from 88 patients with heart valve disease had poor (<10%) MT yet retained cell viability and an ability to raise cytoplasmic Ca2+ in response to vasoconstrictor agents. Comparing across human heart chambers and species, we found that based on patient medical history and six tests, the strongest predictor of poor MT in IMCAs was increased expression of the synthetic marker caldesmon relative to the contractile marker SM-myosin heavy chain. In addition, high resolution imaging revealed a distinct layer of longitudinally aligned SMCs between ECs and radial SMCs, and we show poor MT was associated with disruptions in these cellular alignments.
Conclusion
These data demonstrate the first use of atrial and ventricular biopsies from patients and pigs to reveal that impaired coronary MT reflects a switch of viable SMCs towards a synthetic phenotype, rather than a loss of SMC viability. These arteries represent a model for further studies of coronary microvascular contractile dysfunction
Neutron irradiation of RPCs for the CMS experiment
All the CMS muon stations will be equipped with Resistive Plate Chambers (RPCs). They will be exposed to high neutron background environment during the LHC running. In order to verify the safe operation of these detectors, an irradiation test has been carried out with two RPCs at high neutron flux (about ), integrating values of dose and fluence equivalent to 10 LHC-years. Before and after the irradiation, the performance of the detectors was studied with cosmic muons, showing no relevant aging effects. Moreover, no indication of damage or chemical changes were observed on the electrode surfaces
The RPC system for the CMS experiment at the LHC
The CMS detector at the LHC has a redundant muon system. Two independent muon systems are used in the L1 trigger. One of them is based on wire chambers, the other on RPC detectors. Properly combining the answers of the two systems results in a highly efficient L1 trigger with high flexibility from the point of view of rate control. Simulation results show, however, that the RPC system suffers from false triggers caused by coincidence of spurious hits. System improvements, which could avoid oiling the chambers, are possible. RPCs have also proved to be very useful for muon track reconstruction
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