To evaluate the diagnostic performance of 2-18F-fluoro-2-deoxy-d-glucose (18F-FDG) positron-emission tomography (PET)/computed tomography (CT) in TA diagnosis and Takayasu arteritis (TA) activity ...assessment.
This retrospective study included patients with TA diagnosed according to the American College of Rheumatology (ACR) criteria and undergoing 18F-FDG PET/CT imaging from October 2010 to July 2022. TA activity was assessed through 18F-FDG PET/CT (maximum standard uptake value SUVmax, vascular SUVmax/mean standard uptake value SUVmean of liver (SUV ratio), and PET vascular activity score PETVAS) using physician global assessment (PGA) as the reference standard, and the results of these assessments were compared against the clinical activity scores (National Institutes of Health NIH and Indian Aortitis Disease Activity ITAS-A scores), acute-phase reactants (APR), and white blood cell and platelet counts.
Twenty 18F-FDG PET/CT examinations from 19 patients were included in the study, nine were performed in the active phase and 11 in the inactive phase. The involved vessels showed segmental and tubular FDG uptake in the active group. The average SUVmax, SUV ratio, and PETVAS was 6.3 ± 2.7 (range 3.4–12), 4.2 ± 1.7 (range 2.1–7.5), and 22.7 ± 11.2 (range 6–39), respectively, in the active group and 1.7 ± 0.9 (0.9–3.1), 1.1 ± 0.6 (range 0.6–2.4), and 3.5 ± 5.5 (range 0–18), respectively, in the inactive group. The sensitivity, specificity of SUVmax, SUV ratio, and PETVAS for TA activity assessment were 100%, 100%; 100%, 90.9%; and 88.9, 90.9%, respectively. After ROC curve analysis, a new SUVmax cut-off was obtained. Based on the new cut-off value, SUVmax 3.3 and SUV ratio 1.9 had a more perfect assessment performance.
18F-FDG PET/CT is an alternative imaging technique for TA.
•18F-FDG PET/CT has advantages in TAK activity assessment.•Arterial SUVmax and SUV target/background ratio are important parameters for TAK activity assessment.•18F-FDG PET/CT allows for a more accurate classification of TAK.•PET/CT can better evaluate TAK efficacy
Well-dispersed nylon/graphene nanocomposites were prepared successfully. Graphene can improve the toughness and barrier properties of nylons significantly with very low loadings. Display omitted
...•Well-dispersed nylon/graphene nanocomposites were prepared without use of solvents.•Graphene can improve the toughness and impact performance of nylons significantly.•Graphene can reduce water and oxygen permeability of nylons.
The potential of using functionalized graphene (FG) as reinforcement for producing high performance of nylons 11 and 12 nanocomposites was explored. A series of FG/nylons 11 and 12 nanocomposites fabricated by a direct melt blending with assistance of pre-mixing was assessed for their mechanical and barrier properties as a function of FG loading. The results revealed that the ultimate tensile strength, elongation at break, impact strength, toughness and permeation resistance characteristics were improved by the incorporation of a very small amount of the FG into the nylon matrices. In the nylon12, the ultimate tensile strength increased by ∼35%, elongation at break by ∼200%, fracture toughness by ∼75% and the impact failure energy by ∼85%, respectively, when only 0.6wt% FG was incorporated. In contrast, the tensile mechanical properties and fracture toughness of the nylon11 was only slightly improved by addition of FG, but a dramatic enhancement of ∼250% in impact strength was achieved by adding 1wt% FG. In addition, the graphene sheets were dramatically effective for improvements of vapor and gas barrier properties for both nylons at a very significant low loading. Especially, the nylon11 films with FG loading as low as 0.3wt% showed a superior to reduction of water vapor and oxygen permeability by ∼49% and ∼47%, respectively. In this communication, the effects of FG on these property enhancements of the nylons have been well discussed. It can be concluded that to achieve the maximally improved properties, aside from good dispersion of the filler, strong interface between the polymer and graphene sheets, flexibility of graphene in the polymer matrix could be considered to be also an important factor due to the characteristics of graphene wrinkled structure in the polymer matrix.
The objective of this study is to evaluate the effect of slip ratio on the wear and rolling contact fatigue (RCF) of wheel/rail materials using a rolling–sliding wear testing apparatus. The results ...indicate that two wear types are presented in terms of wear rate: type I (mild wear) and type II (severe wear). In type I wear, cracks propagate parallel to the surface. While in type II, the peeling is aggravated and spalling can be observed. With the slip ratio increasing, the wear mechanism of rollers transforms from slight oxidation wear and peeling to severe fatigue wear and spalling. Due to the mild wear and light plastic deformation in type I, the angle and depth of cracks show no obvious differences between the wheel and rail rollers. The crack depth and angle increase in type II wear owing to severe plastic deformation, while the depth is smaller on the wheel rollers. The size of flake wear debris presents an increasing trend and the main composition is Fe2O3 and metallic iron, and the content of iron diminishes with increasing oxidation.
•Two wear types are defined in terms of wear rate of wheel/rail rollers.•The slip ratio has a significant effect on the hardness and friction coefficient.•Two wear types present different subsurface damages.•The size of debris with flake structure has a downtrend with slip ratio increasing.
Tumor metastasis is responsible for most cancer patients' deaths. Understanding the mechanism of metastasis is crucial for improving the cure rate for cancer. Here, we report that Gankyrin, a ...chaperone of ubiquitin-proteasome, has an essential role in breast cancer metastasis. We find that Gankyrin is highly overexpressed in human breast cancers and the expression correlates strongly with lymph node metastasis. Knocking down Gankyrin expression in highly metastatic human breast cancer cells significantly decreases cancer cell migration and invasion. Furthermore, we demonstrate that depletion of Gankyrin inhibits intrinsic Rac1 activity and induces large focal adhesions. Overexpression of Gankyrin accelerates focal adhesion turnover and increases cell migration. Notably, reduction of Gankyrin expression in mouse mammary tumor cell significantly decreases tumor metastasis to lung in animal models. Therefore, our findings suggest that Gankyrin is crucial for breast cancer metastasis and highlight the potential of Gankyrin as a therapeutic target for tumor metastasis.
The diffuse Galactic γ-ray emission, mainly produced via interactions between cosmic rays and the interstellar medium and/or radiation field, is a very important probe of the distribution, ...propagation, and interaction of cosmic rays in the Milky Way. In this Letter, we report the measurements of diffuse γ rays from the Galactic plane between 10 TeV and 1 PeV energies, with the square kilometer array of the Large High Altitude Air Shower Observatory (LHAASO). Diffuse emissions from the inner (15°<l<125°, |b|<5°) and outer (125°<l<235°, |b|<5°) Galactic plane are detected with 29.1σ and 12.7σ significance, respectively. The outer Galactic plane diffuse emission is detected for the first time in the very- to ultra-high-energy domain (E>10 TeV). The energy spectrum in the inner Galaxy regions can be described by a power-law function with an index of -2.99±0.04, which is different from the curved spectrum as expected from hadronic interactions between locally measured cosmic rays and the line-of-sight integrated gas content. Furthermore, the measured flux is higher by a factor of ∼3 than the prediction. A similar spectrum with an index of -2.99±0.07 is found in the outer Galaxy region, and the absolute flux for 10≲E≲60 TeV is again higher than the prediction for hadronic cosmic ray interactions. The latitude distributions of the diffuse emission are consistent with the gas distribution, while the longitude distributions show clear deviation from the gas distribution. The LHAASO measurements imply that either additional emission sources exist or cosmic ray intensities have spatial variations.
Human epidermal growth factor receptor 2 (HER2) overexpression is not only closely associated with the tumor growth, but is also related to tumor invasion. We here aimed to investigate the mechanism ...of HER2 mediation in the pathogenesis of gastric cancer. The human gastric cancer cell lines SGC-7901, MKN-45, AGS, the immortalized cell line GES-1 derived from normal gastric mucosa. Cell transfection and selection of stable cell lines and the gene and protein levels of HER2 and Matrix metalloproteinase-9 (MMP-9) were examined to determine the molecular relationship between them in the pathogenesis of gastric cancer. The human gastric cancer cell lines SGC-7901, MKN-45, AGS, the immortalized cell line GES-1 derived from normal gastric mucosa. Cell transfection and selection of stable cell lines and the gene and protein levels of HER2 and MMP-9 were examined to determine the molecular relationship between them in the pathogenesis of gastric cancer. We demonstrated that vector-based shRNA significantly knocked down the expression of HER2 and considerably inhibited both the migration and invasion of gastric cancer cells. HER2 knockdown resulted in the downregulation of the expression of MMP-9, whereas HER2 overexpression improved the transcription of MMP-9 through the activation of an MMP-9 promoter. The promoter region of MMP-9 between -2500 and -2000 bp was found to be crucial for the upregulation of HER2-mediated transcription. Furthermore, a truncated promoter (-70 to +63) did not display any transcriptional activity. Cell invasion activity was almost completely inhibited when MMP-9 was knocked down. Conversely, the overexpression of MMP-9 partly rescued the invasion ability of cell strains with knockdown HER2. These findings help further understanding of the molecular mechanisms through which HER2 promotes malignancy, and suggest that targeting both HER2 and MMP-9 may be required to effectively block HER2 signaling in gastric cancer therapy.
Using a low background data sample of 9.7×10^{5} J/ψ→γη^{'}, η^{'}→γπ^{+}π^{-} events, which are 2 orders of magnitude larger than those from the previous experiments, recorded with the BESIII ...detector at BEPCII, the decay dynamics of η^{'}→γπ^{+}π^{-} are studied with both model-dependent and model-independent approaches. The contributions of ω and the ρ(770)-ω interference are observed for the first time in the decays η^{'}→γπ^{+}π^{-} in both approaches. Additionally, a contribution from the box anomaly or the ρ(1450) resonance is required in the model-dependent approach, while the process specific part of the decay amplitude is determined in the model-independent approach.
Before ovulation in mammals, a cascade of events resembling an inflammatory and/or tissue remodeling process is triggered by luteinizing hormone (LH) in the ovarian follicle. Many LH effects, ...however, are thought to be indirect because of the restricted expression of its receptor. Here, we demonstrate that LH stimulation induces the transient and sequential expression of the epidermal growth factor (EGF) family members amphiregulin, epiregulin, and beta-cellulin. Incubation of follicles with these growth factors recapitulates the morphological and biochemical events triggered by LH, including cumulus expansion and oocyte maturation. Thus, these EGF-related growth factors are paracrine mediators that propagate the LH signal throughout the follicle.
Artemisia ordosica is one of the main shrubby perennials belonging to Artemisia species of Asteraceae and could be used in folk Chinese/Mongolian medicine to treat symptoms of various inflammatory ...ailments. The present study was conducted to investigate the protective effects of dietary Artemisia ordosica polysaccharide (AOP) against lipopolysaccharide (LPS) induced oxidative stress in broilers via Nrf2/Keap1 and TLR4/NF-κB pathway. A total of 192 1-day-old Arbor Acres male broilers were randomly allotted to four treatments with 6 replicates (n = 8): (1) CON group, non-challenged broilers fed basal diet; (2) LPS group, LPS-challenged broilers fed basal diet; (3) AOP group, non-challenged broilers fed basal diet supplemented with 750 mg/kg AOP; (4) LPS+AOP group, LPS-challenged broilers fed basal diet supplemented with 750 mg/kg AOP. The trial included starter phase (d 1–14), stress period Ⅰ (d 15–21), convalescence Ⅰ (d 22–28), stress period Ⅱ (d 29–35) and convalescence Ⅱ (d 36–42). During stress period Ⅰ (on d 15, 17, 19 and 21) and stress period Ⅱ (on d 29, 31, 33 and 35), broilers were injected intra-abdominally either with LPS solution or with an equal amount of sterile saline. The results showed that dietary AOP supplementation alleviated LPS-induced reduction in antioxidant enzyme activity and excessive production of ROS, 8-OHdG and PC in serum of broilers challenged with LPS. Moreover, dietary AOP supplementation alleviated the decrease of T-AOC and activities of SOD, CAT and GPx in liver of broilers challenged with LPS by increasing expression of Nrf2, and inhibiting over-expression of Keap1 both at gene and protein level. Additionally, dietary AOP supplementation decreased the over-production of IL-1β and IL-6 in liver of broilers challenged by LPS through decreasing mRNA expression of TLR4, MyD88, NF-κB P65, IL-1β and IL-6, and alleviating the increase of protein expression of TLR4, IKKβ, NF-κB P65, IL-1β, IL-6, and the decrease of protein expression of IkBα. In conclusion, dietary AOP supplementation could alleviate LPS-induced oxidative stress through Nrf2/Keap1 and TLR4/NF-κB pathway.
•Dietary AOP alleviated LPS-induced liver injure.•Dietary AOP relieved LPS-induced oxidative stress by activating Nrf2/keap1 pathway.•Dietary AOP relieved LPS-induced oxidative stress by suppressing TLR4/NF-κB pathway.
We report observations of stimulated electromagnetic emission (SEE) induced by high power high frequency (HF) radio waves near the third electron gyroharmonic (3fce ${f}_{\mathrm{ce}}$) at European ...Incoherent Scatter Radar (EISCAT). It is discovered that stimulated Brillouin scattering (SBS) spectrum behaves similarly as spectral ion lines of the incoherent scatter radar (ISR) for HF pumping frequency above 3fce ${f}_{\mathrm{ce}}$. The SBS spectral width shows correlation with electron to ion temperature ratio Te/Ti. A new inversion method is proposed by incorporating the SBS spectral width within an artificial neural network approach to achieve electron temperature inversion for ionospheric turbulent plasmas. This work provides a potential new technique to diagnose parameters in the modified ionosphere when the ISR is not available.
Plain Language Summary
Nonlinear interaction of high‐power electromagnetic waves and magnetized plasmas produces a plethora of fundamental phenomena. Stimulated electromagnetic emissions (SEEs) arises from nonlinear interaction and induces plasma turbulence observable by incoherent scatter radars (ISR). It is important to compare SEE and ISR spectral lines for understanding nonlinear physics in the resonance regime. The SEE‐based methods may provide complimentary diagnostic tools to the traditional ISR theory. In addition, the SEE‐based inversion theory and method is still lacking due to nonlinear wave‐wave and wave‐particle interaction. The physical correlation between SEEs and ISR spectra will provide benefit for better inversion techniques. This work reports experimental observation and parameter inversion of stimulated Brillouin scatter (SBS) at EISCAT (European Incoherent Scatter Radar). We successfully discover similarity between the ISR ion lines and SBS near the third electron gyroharmonic by high power radio waves at EISCAT. A new diagnostic technique based on SEEs have been developed using physical model and an artificial neural network approach. The inversion of SEEs overcomes the non‐Maxwellian limitations on ISR measurements. These observations demonstrate a physical intrinsic correlation between ISR ion and SBS lines, which provides possibilities for developing new inversion techniques based on SBS in comparison with well‐known ISR theory.
Key Points
Discovery of similarity between high frequency‐induced stimulated Brillouin scattering (SBS) and incoherent scatter radar spectrum
Intelligent stimulated electromagnetic emission inversion architecture proposed by incorporating physical insights within an artificial neural network approach
Novel ionospheric electron temperature inversion based on SBS and downshifted maximum spectral lines
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