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1.
Materials (Basel) ; 16(24)2023 Dec 13.
Article in English | MEDLINE | ID: mdl-38138769

ABSTRACT

A laser power bed fusion (L-PBF) manufacturing process was optimized by analyzing the surface morphology and track width w of single scan tracks (SSTs) on Fe-3.4wt.%Si. An SST was evaluated under process conditions of laser power P, scan speed V, and energy density E = P/V. The SST surface shape was mainly affected by E; desirable thin and regular tracks were obtained at E = 0.3 and 0.4 J/mm. An L-PBF process window was proposed considering the optimal w of SST, and the appropriate range of E for the alloy was identified to be 0.24 J/mm to 0.49 J/mm. w showed a strong relationship with E and V, and an analytic model was suggested. To verify the process window derived from the appropriate w of SST, cubic samples were manufactured with the estimated optimal process conditions. Most samples produced had a high density with a porosity of <1%, and the process window derived from SST w data had high reliability. This study presents a comprehensive approach to enhancing additive manufacturing for Fe-3.4Si alloy, offering valuable insights for achieving high-quality samples without the need for time-intensive procedures.

2.
Foods ; 12(19)2023 Sep 24.
Article in English | MEDLINE | ID: mdl-37835202

ABSTRACT

Marigold (Tagetes spp.) flower petals are the most vital sources of carotenoids, especially lutein esters, for the production of natural lutein to use for food, feed, and pharmaceutical industries. Several marigold cultivars are cultivated globally; however, their lutein ester composition and contents have not been widely investigated. Considering this, this study aimed to identify and quantify prominent carotenoid esters from the flower petals of ten marigold cultivars by liquid chromatography (LC)-diode-array detection (DAD)-mass spectrometry (MS). In addition, tocopherols, phytosterols, and fatty acids were analyzed by gas chromatography (GC)-flame ionization detection (FID) and GC-MS. Furthermore, the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS•+) and 2,2-diphenyl-1-picrylhydrazyl (DPPH•) radical scavenging abilities of lipophilic extracts were determined. The total carotenoid contents varied significantly (p < 0. 05, Tukey HSD) among cultivars, ranging from 25.62 (cv. Alaska)-2723.11 µg/g fresh weight (cv. Superboy Orange). Among the five major lutein-diesters, (all-E)-lutein-3-O-myristate-3'-O-palmitate and lutein dipalmitate were predominant. Among the studied cultivars, α-tocopherol was recorded, ranging from 167.91 (cv. Superboy Yellow) to 338.50 µg/g FW (cv. Taishan Orange). Among phytosterols, ß-sitosterol was the most prevalent phytosterol, ranging between 127.08 (cv. Superboy Yellow) and 191.99 µg/g FW (cv. Taishan Yellow). Palmitic acid (C16:0; 33.36-47.43%) was the most dominant among the fatty acids. In this study, the highest contents of lutein were recorded from cv. Superboy Orange; however, due to the substantially higher flower petal yield, the cv. Durango Red can produce the highest lutein yield of 94.45 kg/ha. These observations suggest that cv. Durango Red and cv. Superboy Orange are the ideal candidates for lutein fortification in foods and also for commercial lutein extraction.

3.
J Ginseng Res ; 47(1): 97-105, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36644392

ABSTRACT

Background: Hyperactivated airway mucosa cells overproduce mucin and cause severe breathing complications. Here, we aimed to identify the effects of saponins derived from Panax ginseng on inflammation and mucin overproduction. Methods: NCI-H292 cells were pre-incubated with 16 saponins derived from P. ginseng, and mucin overproduction was induced by treatment with phorbol 12-myristate 13-acetate (PMA). Mucin protein MUC5AC was quantified by enzyme-linked immunosorbent assay, and mRNA levels were analyzed using quantitative polymerase chain reaction (qPCR). Moreover, we performed a transcriptome analysis of PMA-treated NCI-H292 cells in the absence or presence of Rg5, and differential gene expression was confirmed using qPCR. Phosphorylation levels of signaling molecules, and the abundance of lipid droplets, were measured by western blotting, flow cytometry, and confocal microscopy. Results: Ginsenoside Rg5 effectively reduced MUC5AC secretion and decreased MUC5AC mRNA levels. A systematic functional network analysis revealed that Rg5 upregulated cholesterol and glycerolipid metabolism, resulting in the production of lipid droplets to clear reactive oxygen species (ROS), and modulated the mitogen-activated protein kinase and nuclear factor (NF)-κB signaling pathways to regulate inflammatory responses. Rg5 induced the accumulation of lipid droplets and decreased cellular ROS levels, and N-acetyl-l-cysteine, a ROS inhibitor, reduced MUC5AC secretion via Rg5. Furthermore, Rg5 hampered the phosphorylation of extracellular signal-regulated kinase and p38 proteins, affecting the NF-κB signaling pathway and pro-inflammatory responses. Conclusion: Rg5 alleviated inflammatory responses by reducing mucin secretion and promoting lipid droplet-mediated ROS clearance. Therefore, Rg5 may have potential as a therapeutic agent to alleviate respiratory disorders caused by hyperactivation of mucosa cells.

4.
Nat Commun ; 13(1): 6292, 2022 10 22.
Article in English | MEDLINE | ID: mdl-36272973

ABSTRACT

Pancreatic ductal adenocarcinoma (PDAC) has a poor 5-year overall survival rate. Patients with PDAC display limited benefits after undergoing chemotherapy or immunotherapy modalities. Herein, we reveal that chemotherapy upregulates placental growth factor (PlGF), which directly activates cancer-associated fibroblasts (CAFs) to induce fibrosis-associated collagen deposition in PDAC. Patients with poor prognosis have high PIGF/VEGF expression and an increased number of PIGF/VEGF receptor-expressing CAFs, associated with enhanced collagen deposition. We also develop a multi-paratopic VEGF decoy receptor (Ate-Grab) by fusing the single-chain Fv of atezolizumab (anti-PD-L1) to VEGF-Grab to target PD-L1-expressing CAFs. Ate-Grab exerts anti-tumor and anti-fibrotic effects in PDAC models via the PD-L1-directed PlGF/VEGF blockade. Furthermore, Ate-Grab synergizes with gemcitabine by relieving desmoplasia. Single-cell RNA sequencing identifies that a CD141+ CAF population is reduced upon Ate-Grab and gemcitabine combination treatment. Overall, our results elucidate the mechanism underlying chemotherapy-induced fibrosis in PDAC and highlight a combinatorial therapeutic strategy for desmoplastic cancers.


Subject(s)
Antineoplastic Agents , Cancer-Associated Fibroblasts , Carcinoma, Pancreatic Ductal , Pancreatic Neoplasms , Single-Chain Antibodies , Female , Humans , Cancer-Associated Fibroblasts/metabolism , Vascular Endothelial Growth Factor A/metabolism , Placenta Growth Factor/genetics , Placenta Growth Factor/metabolism , Single-Chain Antibodies/metabolism , Pancreatic Neoplasms/pathology , Carcinoma, Pancreatic Ductal/genetics , Receptors, Vascular Endothelial Growth Factor/metabolism , Antineoplastic Agents/pharmacology , Fibrosis , Pancreatic Neoplasms
5.
Materials (Basel) ; 13(18)2020 Sep 21.
Article in English | MEDLINE | ID: mdl-32967133

ABSTRACT

This study investigated the mechanical properties of steel in flanges, with the goal of obtaining high strength and high toughness. Quenching was applied alone or in combination with tempering at one of nine combinations of three temperatures TTEM and durations tTEM. Cooling rates at various flange locations during quenching were first estimated using finite element method simulation, and the three locations were selected for mechanical testing in terms of cooling rate. Microstructures of specimens were observed at each condition. Tensile test and hardness test were performed at room temperature, and a Charpy impact test was performed at -46 °C. All specimens had a multiphase microstructure composed of matrix and secondary phases, which decomposed under the various tempering conditions. Decrease in cooling rate (CR) during quenching caused reduction in hardness and strength but did not affect low-temperature toughness significantly. After tempering, hardness and strength were reduced and low-temperature toughness was increased. Microstructures and mechanical properties under the various tempering conditions and CRs during quenching were discussed. This work was based on the properties directly obtained from flanges under industrial processes and is thus expected to be useful for practical applications.

6.
J Nanosci Nanotechnol ; 16(5): 4320-7, 2016 May.
Article in English | MEDLINE | ID: mdl-27483752

ABSTRACT

RGO/Resol carbon composites were prepared from a mixture of reduced GO and a low-molecular-weight phenolic resin (Resol) solution. The effects of the calcination temperature, amount of Resol added and KOH treatment on the electrochemical performance of the RGO/Resol composites were investigated. The physical and electrochemical properties of the composite materials were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Brunauer, Emmett and Teller (BET) surface areas measurements, and cyclic voltammetry (CV). The relationships between their physical properties and their electrochemical performance were examined for use as super-capacitors (SCs). The RGO/Resol composite calcined at 400 degrees C after the KOH loading showed dramatically improved electrochemical properties, showing a high BET surface and capacitance of 2190 m2/g and 220 F/g, respectively. The RGO/Resol composites calcined after the KOH treatment showed much better capacitor performance than those treated only thermally at the same temperature without KOH impregnation. The fabrication of high surface electrodes was essential for improving the SCs properties.

7.
AJR Am J Roentgenol ; 191(3): 710-5, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18716097

ABSTRACT

OBJECTIVE: This study was designed to investigate whether the use of MR diskography would result in improved reader confidence over the use of CT diskography alone for evaluating foraminal impingement causing lumbar radiculopathy. SUBJECTS AND METHODS: Sixteen disk levels in 14 consecutive patients with suspected foraminal impingement causing lumbar radiculopathy were prospectively included in the study. A mixture of diluted gadodiamide and iodinated contrast material was injected at each disk level. After diskography, a CT scan (CT diskography) and T1-weighted fat-suppressed MR image (MR diskography) were obtained. Two spine radiologists and an orthopedic spine surgeon independently scored CT diskography and MR diskography for foraminal evaluation on a 3-point scale: 1, low confidence; 2, moderate confidence; and 3, high confidence. Each reader also assessed whether MR diskography showed an additional benefit over CT diskography with regard to the depiction of foraminal abnormalities only. Another radiologist reviewed conventional MR images focused on disk height and morphology. RESULTS: The reviewers' confidence scores for MR diskography were superior to those for CT diskography (reader 1, p = 0.00008; reader 2, p = 0.0008; reader 3, p = 0.0015) (p < 0.05). MR diskography was considered beneficial in 13 of 16 disk levels (reader 1), 14 of 16 (reader 2), and 14 of 16 (reader 3). MR diskography increased the confidence scores for the detection of foraminal impingement, especially in cases of severe disk degeneration, but did not show additional benefits in cases of an extensive vacuum in the disk or large disk extrusion. CONCLUSION: Simultaneous MR diskography and CT diskography with a mixture of gadodiamide and iodinated contrast material may be beneficial for evaluating foraminal impingement causing lumbar radiculopathy.


Subject(s)
Gadolinium DTPA , Intervertebral Disc Displacement/diagnosis , Intervertebral Disc/diagnostic imaging , Intervertebral Disc/pathology , Iohexol , Magnetic Resonance Imaging/methods , Nerve Compression Syndromes/diagnosis , Tomography, X-Ray Computed/methods , Adult , Aged , Cefazolin/administration & dosage , Contrast Media , Drug Combinations , Female , Gadolinium DTPA/administration & dosage , Humans , Image Enhancement/methods , Iohexol/administration & dosage , Lumbar Vertebrae/diagnostic imaging , Lumbar Vertebrae/pathology , Male , Middle Aged , Sensitivity and Specificity , Spinal Nerve Roots/diagnostic imaging , Spinal Nerve Roots/pathology
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