69 research outputs found
Infrared Small Targets Detection based on MRF Model
AbstractAiming at the difficulty in detecting infrared dim small target under strong background clutter, we propose a novel algorithm of infrared dim small target detection based on Markov random fields(MRF) model. We at first use adaptive morphological filter to suppress the background clutter, then introduce new potential function and energy function according to MRF theory and infrared small target image features, and build a target detection model to confirm automatically the location and size of the target. Simulation results show that the algorithm is effective
Use of Xinfeng capsule to treat abarticular pathologic changes in patients with rheumatoid arthritis
AbstractObjectiveTo observe the influence of Xinfeng-capsule (XFC) on abarticular pathologic changes (APCs) and other indices of patients with rheumatoid arthritis (RA) and explore the mechanism of action of XFC in improving such changes.MethodsThree-hundred RA patients were divided randomly into a treatment group (n=150) and control group (n=150). A normal control (NC) group (n=90) was also created. Changes in cardiac function, pulmonary function, anemia indices and platelet parameters of RA patients were measured. Curative effects of the two groups were compared, and comparison carried out with the NC group.ResultsIn 300 RA patients, late diastolic peak flow velocity (A peak) was much higher (P<0.01) and early diastolic peak flow velocity (E peak), E/A, and left ventricular fraction shortening much lower (P<0.01) than those in the NC group. Vital capacity (VC), forced vital capacity in one second, forced vital capacity (FVC), maximal voluntary ventilation (MVV), maximal expiratory flow in 50% of VC (FEF50) and FEF75 were lowered remarkably (P< 0.05 or P<0.01). Platelet count (PLT), plateletcrit (PCT) and mean platelet volume (MPV) increased markedly (P<0.05 or P<0.01), and hemoglobin (Hb) level decreased significantly (P<0.05). After XFC treatment, the A peak and PLT and PCT were much lower (P<0.05), and E/A and the number of red blood cells as well as Hb level were much higher (P< 0.05), as were FVC, MVV and FEF50 (P<0.05 or P< 0.01), in the treatment group than those in the NC group. Total score of pain and swelling in joints, uric-acid level and high-sensitivity C-reactive protein level were much lower, and superoxide dismutase level as well as the number of CD4 + CD25 + regulation T cells (Treg) and CD4 + CD25 + CD127-Treg were much higher (P<0.05 or P<0.01) in the treatment group than those in the NC group.ConclusionRA patients with pathologic changes in joints also suffer from lower cardiac and pulmonary functions and from parameters of anemia and platelet factors. XFC can improve the symptoms of RA patients, ameliorate their cardiac and pulmonary functions and reduce the parameters of anemia and platelet factors. XFC lowers the immune inflammatory reaction to improve APCs in RA patients
Correction to: HIF prolyl hydroxylase inhibition protects skeletal muscle from eccentric contraction induced injury
Following publication of the original article [1], the authors flagged that there is a discrepancy with the Availability of data and materials statement on page 12 of the article
HIF prolyl hydroxylase inhibition protects skeletal muscle from eccentric contraction-induced injury
BACKGROUND: In muscular dystrophy and old age, skeletal muscle repair is compromised leading to fibrosis and fatty tissue accumulation. Therefore, therapies that protect skeletal muscle or enhance repair would be valuable medical treatments. Hypoxia-inducible factors (HIFs) regulate gene transcription under conditions of low oxygen, and HIF target genes EPO and VEGF have been associated with muscle protection and repair. We tested the importance of HIF activation following skeletal muscle injury, in both a murine model and human volunteers, using prolyl hydroxylase inhibitors that stabilize and activate HIF.
METHODS: Using a mouse eccentric limb injury model, we characterized the protective effects of prolyl hydroxylase inhibitor, GSK1120360A. We then extended these studies to examine the impact of EPO modulation and infiltrating immune cell populations on muscle protection. Finally, we extended this study with an experimental medicine approach using eccentric arm exercise in untrained volunteers to measure the muscle-protective effects of a clinical prolyl hydroxylase inhibitor, daprodustat.
RESULTS: GSK1120360A dramatically prevented functional deficits and histological damage, while accelerating recovery after eccentric limb injury in mice. Surprisingly, this effect was independent of EPO, but required myeloid HIF1α-mediated iNOS activity. Treatment of healthy human volunteers with high-dose daprodustat reduced accumulation of circulating damage markers following eccentric arm exercise, although we did not observe any diminution of functional deficits with compound treatment.
CONCLUSION: The results of these experiments highlight a novel skeletal muscle protective effect of prolyl hydroxylase inhibition via HIF-mediated expression of iNOS in macrophages. Partial recapitulation of these findings in healthy volunteers suggests elements of consistent pharmacology compared to responses in mice although there are clear differences between these two systems
Etiologic Diagnosis of Lower Respiratory Tract Bacterial Infections Using Sputum Samples and Quantitative Loop-Mediated Isothermal Amplification
Etiologic diagnoses of lower respiratory tract infections (LRTI) have been relying primarily on bacterial cultures that often fail to return useful results in time. Although DNA-based assays are more sensitive than bacterial cultures in detecting pathogens, the molecular results are often inconsistent and challenged by doubts on false positives, such as those due to system- and environment-derived contaminations. Here we report a nationwide cohort study on 2986 suspected LRTI patients across P. R. China. We compared the performance of a DNA-based assay qLAMP (quantitative Loop-mediated isothermal AMPlification) with that of standard bacterial cultures in detecting a panel of eight common respiratory bacterial pathogens from sputum samples. Our qLAMP assay detects the panel of pathogens in 1047(69.28%) patients from 1533 qualified patients at the end. We found that the bacterial titer quantified based on qLAMP is a predictor of probability that the bacterium in the sample can be detected in culture assay. The relatedness of the two assays fits a logistic regression curve. We used a piecewise linear function to define breakpoints where latent pathogen abruptly change its competitive relationship with others in the panel. These breakpoints, where pathogens start to propagate abnormally, are used as cutoffs to eliminate the influence of contaminations from normal flora. With help of the cutoffs derived from statistical analysis, we are able to identify causative pathogens in 750 (48.92%) patients from qualified patients. In conclusion, qLAMP is a reliable method in quantifying bacterial titer. Despite the fact that there are always latent bacteria contaminated in sputum samples, we can identify causative pathogens based on cutoffs derived from statistical analysis of competitive relationship
Characterization of Cross-linked Alkaline Lignin/Poly (Vinyl Alcohol) Film with a Formaldehyde Cross-linker
On the basis of previous experiments, industrial alkaline lignin/poly (vinyl alcohol) (PVOH) cross-linked films, industrial alkaline lignin/poly (vinyl alcohol) blend films, and neat poly (vinyl alcohol) films were prepared by casting. The films were investigated by Fourier transform infra-red spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetry analysis (TGA), and dynamic mechanical analysis (DMA). The water contact angles for the three kinds of films were studied as well. The crosslinking reaction between alkaline lignin and PVOH was strong, which was attributed to the high hydrolysis degree of PVOH and the high reactivity of formaldehyde. Compared with the neat PVOH film, the crystallinity of the cross-linked film decreased slightly; the thermal stability of the cross-linked film was higher; DMA analysis showed that the Tg and the tanδ magnitude of the alkaline lignin/PVOH reaction film both decreased slightly. Lignin and the cross-linking reaction both improved the water resistance of films. Therefore, this research has provided a detailed analysis of the characterization of the films while exploring the potential of direct usage of industrial alkaline lignin in polymer materials
The Effect of Degradation of Soda Lignin Using Pd/SO42−/ZrO2 as a Catalyst: Improved Reactivity and Antioxidant Activity
To the value-added application of the soda lignin by improving its reactivity and antioxidant activity, a self-made Pd/SO42−/ZrO2 catalyst was used to catalyze the degradation reaction of soda lignin. The catalyst was loaded with the palladium of 1.47 wt.% while retaining the super acidity of SO42−/ZrO2. The reaction condition was determined as follows: the dioxane-water solution was selected as the reaction solution, the addition amount of the catalyst was 5 wt.% of the soda lignin, the system was heated at 100 °C for 4 h under a hydrogen pressure of 3 MPa. The reactivity of the catalyzed-soda lignin compared to the soda lignin before the reaction was significantly improved: the values of phenolic hydroxyl groups and total hydroxyl groups were increased by 35.3% and 97.1%, respectively, and the value of methoxy groups was decreased by 13%. Approximately 63.3% of the β-O-4 bonds were cleaved, which resulted in a reduction of the weight average molecular weight from 8200 g·mol−1 to 4900 g·mol−1. At the same time, the EC50 values of the catalyzed-soda lignin on DPPH (1,1-diphenyl-2-picrylhydrazyl) and ABTS+ (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonate) radicals scavenging were decreased by 20.6% and 32.6%, respectively, and the reducing power of catalyzed-soda lignin at the absorption value of 0.5 was increased by 10.5%. The Pd/SO42−/ZrO2 catalyst works by breaking the β-O-4 linkages and degrading the methoxy groups. The catalyzed-soda lignin exhibits the possibility of being used as the antioxidants, grafting precursors, adhesive additives, and raw materials for lignin/polymer composites
Antioxidant Activity of Organosolv Lignin Degraded Using SO42-/ZrO2 as Catalyst
Organosolv lignin degradation was carried out through hydrogenolysis routes with SO42-/ZrO2 as the catalyst. Structural characterization and antioxidant activity of organosolv lignin samples were investigated; the antioxidant activity of the organosolv lignin was compared with that of soda lignin. Results showed that the active functional groups contents of organosolv lignin were increased, and the antioxidant activity of organosolv lignin was improved. The total hydroxyl and phenolic hydroxyl group contents of organosolv lignin were increased by 15.81% and 26.55%, respectively, and the Mw was decreased from 5739 g/mol to 4499 g/mol. The IC50 of organosolv lignin on DPPH radicals scavenging rate, ABTS+ radicals scavenging rate, and reducing power were decreased by 18.91%, 18.08%, and 8.48%, respectively. The catalyzed organosolv lignin can be used as a natural antioxidant for functional food or in cosmetic and polymeric materials
Correlation between Solubility Parameters and Properties of Alkali Lignin/PVA Composites
Although lignin blending with thermoplastic polymers has been widely studied, the usefulness of the lignin–polymer composites is limited by the poor compatibility of the two components. In the present study, alkali lignin/PVA composite membranes were prepared by incorporating 10%, 15%, 20% and 25% alkali lignin into the composites. The thermodynamic parameters of the composites were measured using inverse gas chromatography (IGC). Composite membranes with 10%, 15%, 20%, and 25% alkali lignin had solubility parameters of 17.51, 18.70, 16.64 and 16.38 (J/cm3)0.5, respectively, indicating that the solubility parameter firstly increased, and then decreased, with increasing proportions of alkali lignin. When the alkali lignin content was 15%, the composites had the largest solubility parameters. The composite membrane with an alkali lignin content of 15% had a tensile strength of 18.86 MPa and a hydrophilic contact angle of 89°. We have shown that the solubility parameters of blends were related to mechanical and hydrophilic properties of the composites and the relationships have been verified experimentally and theoretically
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