Search Results (143)

Background/Objectives: Migraine is a complex neurological headache disorder, and transcutaneous auricular vagus nerve stimulation (taVNS) can effectively relieve headache symptoms, but its mechanism of effect is still unclear. This study aimed to explore the regulatory effects of taVNS on the locus coeruleus (LC) and the norepinephrine (NE) system in migraine mice. Methods: C57/BL6 mice were randomly assigned to four experimental groups: the control group, model group, taVNS group, and sham taVNS group. A migraine model was established by administration of nitroglycerin. Headache behaviors were assessed using the orofacial stimulation test (OST) and the mouse grimace scale (MGS). Immunofluorescence staining was conducted to evaluate the expression of NE neurons in the LC, while Western blotting was used to determine the expression levels of α-2A adrenergic receptors in the spinal trigeminal nucleus caudalis (Sp5C). Additionally, fiber-optic recording was employed to monitor the real-time dynamics of NE release in Sp5C. Results: After taVNS intervention, the drinking time of OST in the model mice was significantly prolonged(p < 0.05), and facial expression scores were reduced (p < 0.05). TaVNS increased the number of NE neurons in the LC (p < 0.05), promoted the release of NE in Sp5C (p < 0.05), and upregulated the expression of α-2A adrenergic receptors in Sp5C (p < 0.05). Conclusions: The analgesic effects of taVNS are related to the activation of the LC-NE system and the inhibition of the decrease in Sp5C in migraine mice. Full article

Background/Objectives: Aortic valve calcification is commonly evaluated using 3.0 mm true non-contrast (TNC) computed tomography (CT) images. This study evaluates the reproducibility of virtual non-contrast (VNC) reconstructions at different slice intervals using photon-counting detector CT (PCD-CT). Methods: In this retrospective study, we included 279 consecutive patients, who underwent PCD-CT for evaluation of native aortic valve between February 2023 and December 2023 with both TNC and VNC images at 3.0 and 1.5 mm slice intervals. Aortic valve calcium score (AVCS) and aortic valve calcium volume (AVCV) were compared between the two methods using paired t-tests. Agreement for continuous variables was assessed using inter-class coefficients (ICCs). Cohen’s Kappa (κ) was calculated to evaluate the agreement between different modalities in diagnosing severe AV calcification. Results: Compared to the standard, TNC images at 1.5 mm intervals showed higher AVCS (mean difference: −290 ± 418, p < 0.001), with high reproducibility between techniques (CS: ICC 0.969, [IQR 0.962, 0.975]). Compared with reference, VNC showed no significant differences in AVCS at either slice intervals, with excellent reproducibility (3.0 mm, ICC 0.970 [0.963, 0.976]; 1.5 mm, ICC 0.971 [0.964, 0.977]). Compared to TNC 3.0 mm, strong concordance was observed using other reconstruction techniques in assessing severe AV calcification (κ = 0.81 [95% CI: 0.74–0.88], 0.83 [95% CI: 0.76–0.90], and 0.83 [95% CI: 0.76–0.90] for TNC at 1.5 mm, VNC at 3.0 mm, and 1.5 mm, respectively), with low misclassification rates. Conclusions: Our study highlights high reproducibility in the evaluation of AVCS by VNC reconstruction at 3.0 and 1.5 mm intervals compared with reference offering a reliable alternative with an excellent diagnostic accuracy. Full article

Spectral detector computed tomography (SDCT) is an innovative imaging technique in veterinary medicine that utilises simultaneous data acquisition at different energy levels using two rows of detectors. This technique provides several interesting applications which improve insights into tissue composition. One implementation is the generation of virtual non-contrast (VNC) images from post-contrast spectral CT data by identifying and subtracting iodine pixels. Preliminary studies suggest that VNC images may offer diagnostic quality comparable to true unenhanced (TUE) images in healthy dogs; however, this technique has yet to be evaluated in clinical patients. This study compared the Hounsfield units (HUs) measured in VNC to those in TUE images of canine hepatic pathologies, taking into account specific types of pathologies based on their imaging characteristics. The attenuation values of the VNC and TUE series were analysed using two one-sided t-tests (TOST), and the signal-to-noise ratio (SNR) was calculated for each region of interest (ROI). A 5-point Likert scale was utilised to assess image noise, quality, and iodine subtraction in the VNC images. A total of 287 ROIs were analysed in the liver, gallbladder, paravertebral muscle, and pancreatic body of 28 dogs with histopathologically confirmed hepatic pathologies. 92.61% of the hepatic ROIs displayed a “negligible” difference of ≤10 HUs between VNC and TUE images, with significant p-values of <0.05 maintained for all ROIs within the limit of ≤10 HUs in the TOST, confirming equivalence between the two imaging modalities. The image quality assessment indicated that SDCT-derived images provided equal or superior quality compared to conventional CT. Therefore, it can be concluded that VNC images calculated from SDCT data could be an alternative to conventional TUE images for hepatic pathologies. Full article

Background/Objectives: Immune checkpoint inhibitors (ICIs) are frontline treatment for advanced Merkel Cell Carcinoma (MCC), regardless of viral status. Frontline ICIs provide durable benefit to only half of patients, highlighting a need for alternative therapies. In this study, the objective is to leverage whole exome sequencing (WES) and transcriptome sequencing (WTS) to distinguish genomic alterations associated with ICI response. Investigate differential genomic alterations between virus-positive (VP) and virus-negative (VN)-MCC to identify novel therapeutic targets. Methods: A total of 95 MCC cases underwent WES and WTS. Utilizing computational pipelines applied to WES, we identified viral status and tumor mutational burden (TMB). RNA-seq data was used to characterize the immune microenvironment. Results: Of 95 MCC cases, 57 (60%) were VP-MCC and 38 (40%) were VN-MCC. Median TMB was higher in VN-MCC (27.5 vs. 1 Muts/Mb). Mutations in TP53, RB1, NOTCH1, KMTD2, KMT2C, and PIK3CA were primarily found in VN-MCC. MAPK Pathway Activity Score, NK cell infiltration, and the immune checkpoint gene CD276 in VN-MCC tumors were upregulated. No overall survival (OS) difference was identified between VP and VN-MCC, even after ICIs. Conclusions: MCC oncogenesis and treatment response transcend viral status. While mutational analysis confirms previous findings, assessment of the transcriptome and tumor microenvironment suggests alternate therapeutic targets. Full article

Background: Hemorrhagic transformation (HT) is a major complication of endovascular thrombectomy (EVT) for acute ischemic stroke (AIS). Objectives: To investigate the factors as sociated with HT in patients with successful recanalization and examine the impact of collateral status (CS) on ischemic progression and outcomes. Methods: We retrospectively analyzed patients with AIS with successful recanalization (modified treatment in cerebral infarction (mTICI) 2B-3) who underwent dual-energy CT (DECT) within 24 h and MRI within 10 days post-EVT. Patients with posterior circulation stroke, missing multiphase CT angiography (CTA) collateral scores, or missing 3-month modified ranking scale scores were excluded from the study. Results: Among the 86 patients, those with HT had a significantly lower proportion of 3-month excellent outcomes and worse imaging scores, including non-contrast CT (NCCT)-Alberta Stroke Program Early CT Score (ASPECTS), virtual non-contrast (VNC)-ASPECTS, and diffusion-weighted imaging (DWI)-ASPECTS. Patients with HT with poor CS had a significantly lower proportion of 3-month excellent outcomes, poorer post-EVT National Institutes of Health Stroke Scale (NIHSS) score, worse imaging scores, including VNC-ASPECTS, and DWI-ASPECTS. In the predictive factor analysis, post-EVT NIHSS and VNC-ASPECTS scores were significantly associated with 3-month excellent functional outcomes (modified Rankin Scale (mRS) 0-1). Conclusions: In patients with successfully recanalized AIS, HT with poor CS was associated with poorer functional outcomes and worse imaging scores, and a 24 h combined measure (post-EVT NIHSS and DECT VNC-ASPECT) show promise for early risk stratification; prospective external validation is warranted before routine use. Full article

For the unrelated parallel machine scheduling problem, an improved Spider Monkey Optimization algorithm incorporating a variable neighborhood search (VNS) mechanism (VNS-SMO) is proposed to minimize the makespan, total tardiness, and total energy consumption. The VNS-SMO incorporates six types of neighborhood searches based on the objective characteristics to strengthen the optimization performance of the algorithm. To verify the effectiveness and superiority of VNS-SMO, first, Taguchi experiments were used to determine the algorithm parameters, and then three instances of different scales were solved and compared with the traditional algorithms NSGA-II, PSO, and SMO. The experimental results indicate that VNS-SMO significantly outperforms the comparison algorithms on IGD, NR, and C-matrix metrics, fully demonstrating its comprehensive advantages in convergence, distribution, and diversity. Full article

Background: Computed tomography (CT) is the standard of reference for diagnosis and follow-up in aortic dissection (AD). Localizing the entry and identifying false and true lumen are as important as differing post-treatment changes from contrast media extravasations. Photon-counting detector CT (PCDCT) allows for virtual monoenergetic (VME) reconstructions, which can augment contrast media effects on lower energy levels, and for virtual non-contrast (VNC) reconstructions. The aim of this study was to analyze the influence of VME reconstructions on contrast media effects in different dissection compartments as well as compare true and VNC series in AD patients. Methods: We retrospectively analyzed PCDCT datasets from 28 patients with aortic dissections, with different dissection types and different treatment statuses. Attenuation and standard deviation values of the ascending and descending aorta, as well as CT values of the false lumen, were measured. These measurements were obtained from VME images at energy levels ranging from 40 to 190 keV in 10 keV increments, as well as from non-contrast (NC) and VNC reconstructions. The signal-to-noise ratio (SNR) was calculated. Additionally, subjective values for dissection assessability and native aspects of the images were acquired for different reconstructions. Results: CT values decreased with higher energy levels in VME imaging. Ascending aorta showed higher attenuation values than descending aorta, which was higher than false lumen (e.g., at 70 keV ascending 357 [310; 419] HU, descending 346 [305; 401] HU and false lumen 298 [248; 363] HU). These differences increased on lower VME reconstructions with statistical significance for the comparisons of ascending and descending aorta with the false lumen on all energy levels. In line with this, SNR showed highest values for ascending aorta compared to descending aorta and false lumen on all energy levels. For NC comparisons, VNC and VME at 190 keV reconstructions showed higher CT values than NC reconstructions (e.g., overall data NC 48 [42; 55] HU, VNC 66 [57; 73] HU, 190 keV 97 [89; 105] HU). Subjective ratings were worse with VNC than with NC images. Conclusions: VME reconstructions on lower energy levels can be helpful in differentiating between true and false lumen in aortic dissections. Full article

N-terminal acetylation, catalyzed by N-terminal acetyltransferase (NAT) complexes, is one of the most prevalent protein modifications in eukaryotic cells, yet its role in heart development remains poorly understood. Here, we use Drosophila as an in vivo platform to investigate the functions of NAT complex components in cardiac development and congenital heart disease (CHD). Focusing on the NatA complex, we showed that cardiac-specific knockdown of each of its three subunits (Naa15-16, vnc, and san) led to developmental lethality, structural disorganization, fibrosis, and impaired cardiac function in Drosophila. Remarkably, human NAA16 completely rescued the cardiac defects in Naa15-16 silenced Drosophila, whereas a CHD-associated variant (NAA16-R70C) failed to do so, providing direct functional evidence of its pathogenicity. Together, these findings suggest the NatA complex as a critical regulator of heart development and provide functional validation linking variants in NatA complex genes to CHD. Further studies in mammalian models will be required to provide additional supporting evidence. Full article

Dissolved oxygen (DO) concentration in nutrient solution is critical for maximizing yield and optimizing quality traits of lettuce plants grown in floating systems. This study evaluated the effects of two aeration systems—a Venturi system (V) and a Venturi system combined with a nanobubble generator using electromagnetic waves (VN)—compared with a non-aerated control (C), on quali-quantitative traits of lettuce plants grown in a floating system over two consecutive harvests. Both aeration treatments significantly increased DO levels in the nutrient solution compared to C, with the VN treatment maintaining the highest value throughout the crop cycle. Although no significant differences in lettuce yield were observed, both aeration treatments enhanced the leaf concentration of P, Mn, Zn, and Cu in the second harvest, and Mg in both harvests. Moreover, the VN treatment lowered leaf nitrate concentration in both harvests compared to the other treatments. The increase in DO in the nutrient solution delayed leaf senescence, as evidenced by higher chlorophyll index and lower anthocyanin levels in the lettuce leaves harvested at the end of the trial for both aeration systems. These results suggest that aeration, particularly with nanobubbles, can be an effective and sustainable strategy to enhance the quality traits of lettuce grown in a floating system. Full article

This study investigated the anticorrosive properties of nitride coatings (V,Zr,Nb)N, VN and (Zr,V)N with a thickness of approximately 3 μm, deposited on a substrate of AISI 321 steel. Experiments were conducted in 3.0 and 0.9% aqueous NaCl solutions. The results indicate that the use of (V,Zr,Nb)N, VN and (Zr,V)N coatings to protect AISI 321 steel in corrosive environments (e.g., chloride-containing solutions) allowed corrosion currents to be reduced by 10–20 times (from 7.0 to 0.29 μA/cm²) for a sample with a (Zr,V)N coating in a 3.0% aqueous NaCl solution, and by 2 times (from 0.36 to 0.18 μA/cm²) for a sample with a (V,Zr,Nb)N coating in a 0.9% aqueous NaCl solution. Based on the distribution of elements on the surface of the samples after holding for 168 h in a 3.0% aqueous NaCl solution at 25 °C, it can be qualitatively concluded that the oxidation intensity of the (Zr,V)N coating was the lowest under this condition, and that the VN coating exhibited the highest oxidation intensity among the considered coatings. Analysis of the structure of the (Zr,V)N coating after holding in a 3.0% aqueous NaCl solution for 168 h at 25 °C shows the presence of nanometre-sized chips, while the analysis of the distribution of elements does not record the presence of anything other than the elements comprising the coating. Based on the distribution of elements on the surface of the VN coating, it can be assumed that the destruction of this coating mainly occurs due to peeling off from the substrate; however, corrosion processes also occur in the VN coating itself. Analysis of the distribution of elements in the surface layers of the (V,Zr,Nb)N coating did not show noticeable signs of oxidation. The destruction of this coating occurs due to fragments peeling off from the substrate, while oxidation processes and substrate corrosion do not have a significant effect on the process of (V,Zr,Nb)N coating destruction. Full article

Lennox–Gastaut syndrome (LGS) is a severe form of childhood-onset epilepsy, often associated with pharmacoresistance. As complete seizure control is usually not achievable with the use of drug therapy, non-pharmacological treatment may be offered to intractable patients. In this review, we are going to present literature reports on various non-pharmacological treatments, including surgical and dietary methods. Surgical interventions, such as resective surgery, corpus callosotomy (CC), or neuromodulation therapies such as vagus nerve stimulation (VNS), deep brain stimulation (DBS), and responsive neurostimulation (RNS), can be offered to pharmacoresistant patients. If the epileptogenic area can be detected, resective surgery is a treatment of choice. On the contrary, if non-invasive and invasive diagnostic methods fail to detect epileptogenic lesions, CC and VNS are considered palliative surgical methods. While both CC and VNS are considered effective in seizure reduction, CC is still more popular than VNS, although VNS seems to be related to better tolerability. Although all neuromodulation therapies require multidirectional optimization, DBS appears to be particularly promising for LGS. The classic ketogenic diet (cKD) is considered an effective and well-tolerated method in LGS treatment. The modified Atkins diet (MAD) and the low glycemic index treatment (LGIT) could be used as valuable alternatives due to their lower restrictiveness and better tolerability. Moreover, combinations of several treatment methods could significantly improve LGS patients’ seizure outcomes. Full article

Rebar is a critical material in concrete constructions like high-rise buildings and seismic-resistant structures. To enhance its properties, microalloying with nitrogen is employed, but traditional methods using micro alloy additives such as vanadium (FeV), niobium (FeNb), titanium (FeTi), and vanadium nitride (VN) face issues of high costs, reduced purity, and difficulty in controlling molten steel composition. This article presents a novel approach of injecting top-blown O₂–N₂ mixed gas to increase nitrogen content efficiently. Experiments simulated HRB400 steel samples, varying N₂ ratios (10%, 20%, 30%, 40%), temperatures (1500 °C, 1550 °C, 1600 °C), and blowing times (1, 2, 3 min). Results show that optimized parameters enable nitrogen content adjustment from 50 to 104 ppm, with nitrogen utilization improved to 5.4%. This method utilizes inexpensive N₂ gas, reduces impurities, and provides precise control, offering a cost-effective and sustainable solution for high-performance steel production by replacing costly alloys and meeting nitrogen requirements. Full article

Vanadium nitride (VN) ceramic layers were deposited on 304L stainless steel specimens by direct current (DC) magnetron sputtering in an Ar/N₂ gas mixture at substrate temperatures of 250 °C, 300 °C, and 350 °C. The obtained films were evaluated by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). The results showed the existence of VN and V₂N phases in the as-deposited coatings. It was found that the surface roughness parameter (Ra = 10 nm) decreased with increasing substrate temperatures up to 350 °C. The highest hardness (10.6 GPa) was achieved in the layer produced at 300 °C. The low values of plastic and elastic deformation, as well as a low friction coefficient (0.38), led to an enhancement in the coatings’ tribological properties. The film’s thickness increased with increasing temperature due to the presence of nucleation centers in the films. The highest thickness (557 nm) was achieved in the layer deposited at 350 °C. The electrochemical tests exhibited reliable protection against corrosion in strongly aggressive electrolytes. It has been proven that the temperature significantly affects the ceramic coatings’ structural, morphological, tribological, and corrosion properties. Full article

Invar alloy is widely used for manufacturing precision instruments owing to its exceptionally low thermal expansion property. Nevertheless, conventional invar alloys usually lack the sufficient strength required for engineering applications, so there is an urgent need for innovative approaches to enhance the strength. In this study, the possibility of elevating the strength and preserving the low coefficient of thermal expansion (CTE) of invar alloy is investigated by combining deformation strengthening with the V (C, N) precipitation strengthening mechanism. The increase in dislocation density resulting from deformation treatment promotes the V (C, N) precipitation. This leads to a significant enhancement in the strength of alloys after cold-rolling aging compared to direct aged counterparts, while preserving the low CTE. After a cold-rolling deformation with a 40% reduction and subsequent aging at 650 °C for 3 h, the V-N invar alloy exhibits a tensile strength of 907 MPa and an elongation of 6.9%, demonstrating the optimal mechanical properties. In addition, the CTE value maintains a low value of 1.31 × 10⁻⁶/°C within the temperature range of 20 to 100 °C. These findings are vital for developing high-strength, low-CTE invar alloys. Full article

Background/Objectives: Virtual non-contrast (VNC) images derived from dual-energy CTA (DE-CTA) could potentially replace true non-contrast (TNC) scans while reducing radiation exposure. This study evaluated the image quality of VNC compared to TNC for assessing native arteries and bypass grafts in patients with peripheral arterial disease (PAD). Methods: We retrospectively analyzed 175 patients (111 men, 64 women, mean age: 69.3 ± 9.5 years) with PAD who underwent lower extremity DE-CTA. Mean attenuation and image noise values of TNC and VNC images were measured in native arteries and bypass grafts at six arterial levels, from the aorta to the popliteal arteries, using circular regions of interest (ROI). Signal-to-noise ratios (SNRs) and contrast-to-noise ratios (CNRs) were calculated. Three independent radiologists evaluated the subjective image quality of VNC images compared to baseline TNC scans for overall quality (4-point Likert scale), and for residual contrast medium (CM), calcium subtractions, and bypass graft visualization (3-point Likert scales). Radiation dose parameters (DLP, CTDIvol) were recorded to estimate effective dose values (ED) and the potential radiation dose reduction. Differences between TNC and VNC measurements and radiation dose parameters were compared using a paired t-test. Interobserver agreement was assessed with Gwet’s AC2. Results: VNC attenuation and noise values were significantly lower across all native arterial levels (p < 0.05, mean difference: 4.7 HU–10.8 HU) and generally lower at all bypass regions (mean difference: 2.2 HU–13.8 HU). Mean image quality scores were 3.03 (overall quality), 2.99 (residual contrast), 2.04 (subtracted calcifications), and 3.0 (graft visualization). Inter-reader agreement was excellent for each assessment (AC2 ≥ 0.81). The estimated radiation dose reduction was 36.8% (p < 0.0001). Conclusions: VNC reconstructions demonstrated comparable image quality to TNC in a PAD assessment and offer substantial radiation dose reduction, supporting their potential as a promising alternative in clinical practice. Further prospective studies and optimization of reconstruction algorithms remain essential to confirm diagnostic accuracy and address remaining technical limitations. Full article