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Six ionone glycosides (1–3 and 5–7), including three new ones, named capitsesqsides A−C (1–3), together with an eudesmane sesquiterpenoid glycoside (4) and three known triterpenoid saponins (8–10) were isolated from Rhododendron capitatum. The structures of these compounds were determined by extensive spectroscopic techniques (MS, UV, 1D-NMR, and 2D-NMR) and comparison with data reported in the literature. The absolute configurations were determined by comparison of the experimental and theoretically calculated ECD curves and LC-MS analyses after acid hydrolysis and derivatization. The anti-inflammatory activities of these compounds were evaluated in the LPS-induced RAW264.7 cells. Molecular docking demonstrated that 2 has a favorable affinity for NLRP3 and iNOS. [ABSTRACT FROM AUTHOR]

Al 6082 aluminum alloy has excellent corrosion resistance, strength, and formability. However, owing to the recrystallization effect of a hot working process, coarse grains form easily in this material, which reduces its strength and service life. The novel continuous casting direct rolling (CCDR) method can prevent the deterioration of this material. Thus, we used CCDR Al 6082 aluminum alloy as the research material in this study. By subjecting a CCDR Al 6082 aluminum alloy to heat treatment (T4 and T6) and cold rolling, the influence of recrystallization effect on its mechanical properties and on impact failure resistance were explored. The results demonstrated that the specimen subjected to T4 heat treatment had a higher elongation and that the specimen subjected to T6 heat treatment had a higher strength. After cold rolling, the hardness and strength of the specimens subjected to different heat treatments (coded T4R4 and T6R4) increased because of the work's hardening effect. Moreover, the elongations of both specimens decreased, but they were higher than the industrial standard (>10%). The strength of specimen T6R4 was higher (up to 400 MPa) than specimen T4R4. Moreover, relative to specimen T4R4, specimen T6R4 had greater tensile and Charpy impact failure toughness. [ABSTRACT FROM AUTHOR]

Currently, the primary commercial aluminum alloy fillers used are 4043 and 5356. However, when welded with high-strength work pieces like 6061 and 7075 aluminum alloys, the strength of weld beads significantly lags behind that of the original welded material. Both 4043 and 5356 aluminum alloys cannot be strengthened through heat treatment. The strength difference between the weld bead and base material doubles after heat treatment. In this study, an Al-Si-Cu-Mg alloy (SCM) filler modified using a heat-treatable A319 aluminum alloy was employed to investigate the post-welding microstructural and mechanical properties of specimens under room- and high-temperature conditions and after prolonged exposure in a saltwater environment (3.5 wt.% NaCl). The aim was to demonstrate that commercial aluminum alloy fillers could be substituted with a high-silicon aluminum alloy boasting excellent solidification and mechanical properties. The results revealed that, after heat treatment of the weld bead, dendrites were not eliminated, but the tensile strength increased to 310 MPa, closely matching that of commercial 6061 aluminum alloy. The strength of the weld bead remained higher than 250 MPa in high-temperature (240 °C) and saltwater environments. These findings underscore the potential application of this material. [ABSTRACT FROM AUTHOR]

This study conducts low-vacuum sulfidation to form a sulfidation layer on the serpentinite-derived magnesium iron silicate, thereby enhancing its electrochemical properties. Results show (Mg,Fe)2SiO4 calcined at 900 °C has the best crystallinity, and the cubic FeS2 is synthesized on the surface of the orthorhombic magnesium iron silicate (MFS). Two distinct charge plateaus can be distinguished during the first charge process, and the discharge capacities increased significantly. This study confirms that the surface FeS2 layer provides extra ion pathways, allowing more lithium/magnesium ions to be extracted and inserted in the serpentinite-derived magnesium iron silicate. Accordingly, the serpentinite electrode boasts straightforward exploitation with low-cost advantages and potential. [ABSTRACT FROM AUTHOR]

This study focuses on the additive manufacturing technique of selective laser melting (SLM) to produce Ti-6Al-4V-Zn titanium alloy. The addition of zinc at 0.3 wt.% was investigated to improve the strength and ductility of SLM Ti-6Al-4V alloys. The microstructure and mechanical properties were analyzed using different vacuum heat treatment processes, with the 800-4-FC specimen exhibiting the most favorable overall mechanical properties. Additionally, zinc serves as a stabilizing element for the β phase, enhancing the resistance to particle erosion and corrosion impedance of Ti-6Al-4V-Zn alloy. Furthermore, the incorporation of trace amounts of Zn imparts improved impact toughness and stabilized high-temperature tensile mechanical properties to SLM Ti-6Al-4V-Zn alloy. The data obtained serve as valuable references for the application of SLM-64Ti. [ABSTRACT FROM AUTHOR]

Chloride ions contained in the sealing compound currently used in the electronic packaging industry not only interact with intermetallic compounds but also have a serious impact on silver alloy wires. A 15 μm ultrafine quaternary silver-palladium-gold-platinum alloy wire was used in this study. The wire and its bonding were immersed in a 60 °C saturated sodium chloride solution (chlorination experiment), and the strength and elongation before and after chlorination were measured. Finally, the fracture surface and cross-section characteristics were observed using a scanning electron microscope and focused ion microscope. The results revealed that chloride ions invade the wire along the grain boundary, and chlorides have been generated inside the cracks to weaken the strength and elongation of the wire. In addition, chloride ions invade the interface of the wire bonding to erode the aluminum substrate after immersing it for enough long time, causing galvanic corrosion, which in turn causes the bonding joint to separate from the aluminum substrate. [ABSTRACT FROM AUTHOR]

The anti-cancer effects of selenylated plant polysaccharides are a focus of research. As a natural plant with extensive biological effects, there have been few studies related to edible purslane (Portulaca oleracea L.). Thus, in this study, soluble P. oleracea polysaccharides (PPS) were extracted from the dried P. oleracea and then selenylated chemically using the HNO3-Na2SeO3 method to obtain two selenylated products, namely, SePPS1 and SePPS2. Compared with the extracted PPS, SePPS1 and SePPS2 had much higher Se contents (840.3 and 1770.5 versus 66.0 mg/kg) while also showing lower contents in three saccharides—arabinose, fucose, and ribose—and higher contents in seven saccharides including galactose, glucose, fructose, mannose, rhamnose, galacturonic acid, and glucuronic acid, but a stable xylose content demonstrated that the performed chemical selenylation of PPS led to changes in monosaccharide composition. Moreover, SePPS1 and SePPS2 shared similar features with respect to monosaccharide composition and possessed higher bioactivity than PPS in human colon cancer HCT-116 cells. Generally, SePPS1 and SePPS2 were more active than PPS with respect to cell growth inhibition, the alteration of cell morphology, disruption of mitochondrial membrane potential, intracellular reactive oxygen species (ROS) generation, the induction of cell apoptosis, and upregulation or downregulation of five apoptosis-related genes and proteins such as Bax, Bcl-2, caspases-3/-9, and cytochrome C, that cause cell apoptosis and growth suppression via the ROS-mediated mitochondrial pathway. SePPS2 consistently showed the highest capacity to exert these observed effects on the targeted cells, suggesting that the performed chemical selenylation of PPS (in particular when higher degrees of selenylation are reached) resulted in an increase in activity in the cells. It can thus be concluded that the performed selenylation of PPS was able to incorporate inorganic Se into the final PPS products, changing their monosaccharide composition and endowing them with enhanced nutraceutical and anti-cancer effects in the colon. [ABSTRACT FROM AUTHOR]

Al–Mg–Sc–Zr alloy fabricated through selective laser melting (SLM) is an additive manufacturing alloy with promising industrial potential. In this study, as-printed specimens were subjected to either single-stage or two-stage heat treatment processes to investigate the effect of temperature from room temperature to high temperature on the specimens' tensile and fatigue properties to establish a reliable reference for aerospace applications. The tensile test results indicated that the heat treatment contributed to determine the properties of the nanoprecipitate Al3(Sc, Zr) with a strengthening phase, improving tensile strength. Moreover, the dynamics strain aging (DSA) effect vanished as temperature increased. It is noteworthy that the nanoprecipitation was distributed at the boundary of the melting pool after single-stage heat treatment with the highest tensile properties in all tests. In addition, the microstructure observed after the two-stage heat treatment indicated a melting pool interface decomposition, and the nanoprecipitation was homogeneously scattered over the Al matrix, increasing strength and further delaying fatigue crack transmission. Those features build a high-fatigue-resistance foundation. TEM analysis also confirmed the promotion of Sc thermal diffusion and an Al3(Sc, Zr) precipitation transformation mechanism under two-stage heat treatment, corresponding to aforementioned inferences. The SLM Al–Mg–Sc–Zr alloy with two-stage heat treatment brings about balance between tensile properties and fatigue resistance, providing new insight into additive manufacturing with Al alloys. [ABSTRACT FROM AUTHOR]

The selenylated polysaccharides chemically belong to the organic Se-conjugated macromolecules and have recently been attracting more and more attention due to their potential to promote body health or prevent cancers. Longan (Dimocarpus longan L.), as a subtropical fruit, contains soluble and non-digestible polysaccharides that are regarded with health care functions in the body. In this study, the longan polysaccharides (LP) were obtained via enzyme-assisted water extraction, and then chemically selenylated using a reaction system composed of HNO3–Na2SeO3 to yield two selenylated products, namely, SeLP1 and SeLP2, with Se contents of 1.46 and 4.79 g/kg, respectively. The anti-cancer effects of the three polysaccharide samples (LP, SeLP1, and SeLP2) were thus investigated using the human colon cancer HT-29 cells as the cell model. The results showed that SeLP1 and SeLP2 were more able than LP to inhibit cell growth, alter cell morphology, cause mitochondrial membrane potential loss, increase intracellular reactive oxygen and [Ca2+]i levels, and induce apoptosis via regulating the eight apoptosis-related genes and proteins including Bax, caspases-3/-8/-9, CHOP, cytochrome c, DR5, and Bcl-2. It was thereby proven that the selenylated polysaccharides could induce cell apoptosis via activating the death receptor, mitochondrial-dependent, and ER stress pathways. Collectively, both SeLP1 and SeLP2 showed higher activities than LP in HT-29 cells, while SeLP2 was consistently more active than SeLP1 in exerting these assessed anti-cancer effects on the cells. In conclusion, this chemical selenylation covalently introduced Se into the polysaccharide molecules and caused an enhancement in their anti-cancer functions in the cells, while higher selenylation extent was beneficial to the activity enhancement of the selenylated products. [ABSTRACT FROM AUTHOR]

As of August 2021, there have been over 200 million confirmed case of coronavirus disease 2019 caused by severe acute respiratory syndrome coronavirus and more than 4 million COVID-19-related deaths globally. Although real-time polymerase chain reaction is considered to be the primary method of detection for SARS-CoV-2 infection, the use of serological assays for detecting COVID-19 antibodies has been shown to be effective in aiding with diagnosis, particularly in patients who have recovered from the disease and those in later stages of infection. Since it has a high detection rate and few limitations compared to conventional enzyme-linked immunosorbent assay protocols, we used a lateral flow immunoassay as our diagnostic tool of choice. Since lateral flow immunoassay results interpreted by the naked eye may lead to erroneous diagnoses, we developed an innovative, portable device with the capacity to capture a high-resolution reflectance spectrum as a means of promoting diagnostic accuracy. We combined this spectrum-based device with commercial lateral flow immunoassays to detect the neutralizing antibody in serum samples collected from 30 COVID-19-infected patients (26 mild cases and four severe cases). The results of our approach, lateral flow immunoassays coupled with a spectrum-based reader, demonstrated a 0.989 area under the ROC curve, 100% sensitivity, 95.7% positive predictive value, 87.5% specificity, and 100% negative predictive value. As a result, our approach exhibited great value for neutralizing antibody detection. In addition to the above tests, we also tested plasma samples from 16 AstraZeneca-vaccinated (ChAdOx1nCoV-19) patients and compared our approach and enzyme-linked immunosorbent assay results to see whether our approach could be applied to vaccinated patients. The results showed a high correlation between these two approaches, indicating that the lateral flow immunoassay coupled with a spectrum-based reader is a feasible approach for diagnosing the presence of a neutralizing antibody in both COVID-19-infected and vaccinated patients. [ABSTRACT FROM AUTHOR]

Cisplatin-based chemotherapy is the standard treatment for bladder urothelial carcinoma (UC). Most patients experience chemoresistance, the primary cause of treatment failure, which leads to disease relapse. The underlying mechanism of chemoresistance involves reduced apoptosis. In this study, we investigated the antitumor effect of the deubiquitylating enzyme inhibitor PR-619 in cisplatin-resistant bladder UC. Deubiquitinase (ubiquitin-specific protease 14 (USP14) and USP21) immunohistochemical staining demonstrated that deubiquitination is related to chemoresistance in patients with metastatic UC and may be a target for overcoming chemoresistance. Cytotoxicity and apoptosis were assessed using fluorescence-activated flow cytometry and a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium assay, and PR-619 was found to enhance the cytotoxic and apoptotic effects of cisplatin in cisplatin-resistant T24/R cells. Mitigated cisplatin chemoresistance was associated with the concurrent suppression of c-Myc expression in T24/R cells. Moreover, the expression of c-Myc was upregulated in human bladder UC specimens from patients with chemoresistance. Experiments in a xenograft nude mouse model confirmed that PR-619 enhanced the antitumor effects of cisplatin. These results are promising for the development of therapeutic strategies to prevent UC chemoresistance through the combined use of chemotherapeutic agents/deubiquitination inhibitors (PR-619) by targeting the c-Myc pathway. [ABSTRACT FROM AUTHOR]

The coronavirus disease 2019 (COVID-19) pandemic with high infectivity and mortality has caused severe social and economic impacts worldwide. Growing reports of COVID-19 patients with multi-organ damage indicated that severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) may also disturb the cardiovascular system. Herein, we used human induced pluripotent stem cell (iPSC)-derived cardiomyocytes (iCMs) as the in vitro platform to examine the consequence of SARS-CoV2 infection on iCMs. Differentiated iCMs expressed the primary SARS-CoV2 receptor angiotensin-converting enzyme-II (ACE2) and the transmembrane protease serine type 2 (TMPRSS2) receptor suggesting the susceptibility of iCMs to SARS-CoV2. Following the infection of iCMs with SARS-CoV2, the viral nucleocapsid (N) protein was detected in the host cells, demonstrating the successful infection. Bioinformatics analysis revealed that the SARS-CoV2 infection upregulates several inflammation-related genes, including the proinflammatory cytokine tumor necrosis factor-α (TNF-α). The pretreatment of iCMs with TNF-α for 24 h, significantly increased the expression of ACE2 and TMPRSS2, SASR-CoV2 entry receptors. The TNF-α pretreatment enhanced the entry of GFP-expressing SARS-CoV2 pseudovirus into iCMs, and the neutralization of TNF-α ameliorated the TNF-α-enhanced viral entry. Collectively, SARS-CoV2 elevated TNF-α expression, which in turn enhanced the SARS-CoV2 viral entry. Our findings suggest that, TNF-α may participate in the cytokine storm and aggravate the myocardial damage in COVID-19 patients. [ABSTRACT FROM AUTHOR]

Currently, the primary commercial aluminum alloy fillers used are 4043 and 5356. However, when welded with high-strength work pieces like 6061 and 7075 aluminum alloys, the strength of weld beads significantly lags behind that of the original welded material. Both 4043 and 5356 aluminum alloys cannot be strengthened through heat treatment. The strength difference between the weld bead and base material doubles after heat treatment. In this study, an Al-Si-Cu-Mg alloy (SCM) filler modified using a heat-treatable A319 aluminum alloy was employed to investigate the post-welding microstructural and mechanical properties of specimens under room- and high-temperature conditions and after prolonged exposure in a saltwater environment (3.5 wt.% NaCl). The aim was to demonstrate that commercial aluminum alloy fillers could be substituted with a high-silicon aluminum alloy boasting excellent solidification and mechanical properties. The results revealed that, after heat treatment of the weld bead, dendrites were not eliminated, but the tensile strength increased to 310 MPa, closely matching that of commercial 6061 aluminum alloy. The strength of the weld bead remained higher than 250 MPa in high-temperature (240 °C) and saltwater environments. These findings underscore the potential application of this material.