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One of the important monitoring indicators of the air pollution is atmospheric fine particulate matter (PM2.5), which can induce lung inflammation after inhalation. Coelonin can alleviate PM2.5‐induced macrophage damage through anti‐inflammation. However, its molecular mechanism remains unclear. We hypothesized that macrophage damage may involve the release of inflammatory cytokines, activation of inflammatory pathways, and pyrosis induced by inflammasome. In this study, we evaluated the anti‐inflammation activity of coelonin in PM2.5‐induced macrophage and its mechanism of action. Nitric oxide (NO) and reactive oxygen species (ROS) production were measured by NO Assay kit and dichlorofluorescein‐diacetate (DCFH‐DA), and apoptosis were measured by Flow cytometry and TUNEL staining. The concentration of inflammatory cytokines production was measured with cytometric bead arrays and ELISA kits. The activation of NF‐κB signaling pathway and NLRP3 inflammasome were measured by immunofluorescence, quantitative reverse transcription‐polymerase chain reaction and western blot. As expected, coelonin pretreatment reduced NO production significantly as well as alleviated cell damage by decreasing ROS and apoptosis. It decreased generation of interleukin (IL)‐6 and tumor necrosis factor (TNF)‐α in PM2.5‐induced RAW264.7 and J774A.1 cells. Moreover, coelonin markedly inhibited upregulating the expression of toll‐like receptor (TLR)4 and cyclo‐oxygenase (COX)‐2, blocked activation of p‐nuclear factor‐kappa B (NF‐κB) signaling pathway, and suppressed expression of NLRP3 inflammasome, ASC, GSDMD, IL‐18 and IL‐1β. In conclusion, the results showed that coelonin could protect against PM2.5‐induced macrophage damage via suppressing TLR4/NF‐κB/COX‐2 signaling pathway and NLRP3 inflammasome activation in vitro. [ABSTRACT FROM AUTHOR]

Certain mutations in mitochondrial DNA (mtDNA) are associated with Leber's hereditary optic neuropathy (LHON). In particular, the well-known NADH dehydrogenase 4 (ND4) m.11778G>A mutation is one of the most common LHON-associated primary mutations worldwide. However, how specific mtDNA mutations, or variants, affect LHON penetrance is not fully understood. The aim of the current study was to explore the relationship between mtDNA mutations and LHON, and to provide useful information for early detection and prevention of this disease. Following the molecular characterization of a Han Chinese family with maternally inherited LHON, four out of eight matrilineal relatives demonstrated varying degrees of both visual impairment and age of onset. Through PCR amplification of mitochondrial genomes and direct Sanger sequencing analysis, a homoplasmic mitochondrial-encoded ND4 m.11778G>A mutation, alongside a set of genetic variations belonging to human mtDNA haplogroup B5b1 were identified. Among these sequence variants, alanine transfer RNA (tRNA)Ala m.5601C>T was of particular interest. This variant occurred at position 59 in the TψC loop and altered the base pairing, which led to mitochondrial RNA (mt-RNA) metabolism failure and defects in mitochondrial protein synthesis. Bioinformatics analysis suggested that the m.5601C>T variant altered tRNAAla structure. Therefore, impaired mitochondrial functions caused by the ND4 m.11778G>A mutation may be enhanced by the mt-tRNAAla m.5601C>T variant. These findings suggested that the tRNAAla m.5601C>T variant might modulate the clinical manifestation of the LHON-associated primary mutation. [ABSTRACT FROM AUTHOR]

Highly uniformed barium-strontium titanate nanotube arrays were fabricated using a porous anodic aluminum oxide template from a barium-strontium titanate sol-gel solution. Electron microscope results showed that nanotubes with uniform length and diameter were obtained. The diameters and lengths of these nanotubes were dependent on the pore diameter and the thickness of the applied anodic aluminum oxide template. High resolution transmission electron microscopy and the selected-area electron diffraction pattern investigations demonstrated the perovskite structure and the polycrystalline of the fabricated barium-strontium titanate nanotubes. The characterization of the electrical and dielectric properties had also been made. Compared to thin film material, the intrinsic leakage current density is almost the same. Besides, at 30 °C, the dielectric constant and dielectric loss of the fabricated nanotube is 80 and 0.027 at 1 MHz respectively. [ABSTRACT FROM AUTHOR]

Abstract: The Bi4Ti3O12 and Bi3.25La0.75Ti3O12 thin films were prepared on the Pt/Ti/SiO2/Si substrate using the sol–gel method. The microstructure and ferroelectric properties of these films were investigated. Both the Bi4Ti3O12 and Bi3.25La0.75Ti3O12 thin films exhibited typical bismuth-layered perovskite structure and the single perovskite phase was obtained at 550°C. The structures of Pt/Bi4Ti3O12/Pt and Pt/Bi3.25La0.75Ti3O12/Pt were fabricated. The 2Pr value of Bi3.25La0.75Ti3O12 thin films was much higher than that of Bi4Ti3O12 thin films. The Bi3.25La0.75Ti3O12 films showed fatigue-free behavior. The La doping effects on the crystal structure and ferroelectric properties of Bi4Ti3O12 films were investigated. The mechanism of improvement of ferroelectric properties was discussed. [Copyright &y& Elsevier]

Bi1.5Zn1.0Nb1.5O7/Ba0.6Sr0.4TiO3/Bi1.5Zn1.0Nb1.5O7 (BZN/BST/BZN) sandwich films were deposited by radio frequency magnetron sputtering. The relative permittivity and dielectric loss of the sandwich films were measured using planar Pt/BZN/BST/BZN/Pt/Ti/SiO2/Si capacitor structures. The sandwich films with thickness of about 280 nm exhibited relative permittivity around 206–247 and dielectric loss tangent (tan δ) less than 0.008 at 1 MHz. Films annealed at 750 °C had an ∼11% relative tunability of the permittivity at a maximum applied bias field of 0.77 MV/cm. The sandwich films are not ferroelectric at room temperature. [ABSTRACT FROM AUTHOR]

La3+ and V5+ co-doped BiFeO3 ceramics are synthesized by rapid liquid sintering technique. The modulated structure in Bi0.85La0.15Fe0.97V0.03O3 is investigated by using transmission electron microscopy (TEM). Two kinds of superstructures are observed in the samples. One is the component modulated superstructure and twin-domain, which is generated by La3+ ordered substitution for Bi3+ and frequently appears. The chemical composition of the superstructure is explored by x-ray energy dispersive spectroscopy (EDS). The model of the ordered structure is proposed. Simulation based on the model is conducted. The second is the fluorite-type δ-Bi2O3 related superstructure. The relation between the ferroelectric property and the microstructure of the sample is also discussed. [ABSTRACT FROM AUTHOR]

We have investigated the preparation and properties of Bi4Zr0.5Ti2.5O12 thin films on the LaNiO3 bottom electrode. The Bi4Zr0.5Ti2.5O12 thin films were fabricated on the LaNiO3 bottom electrode using the sol–gel method. The structure and morphology of the films were characterized using x-ray diffraction and scanning electron microscopy. The results show that the films are a perovskite phase with a dense microstructure. The 2Pr and 2Vc of the Pt/BZT/LaNiO3 capacitor are 28.2 µC cm−2 and 14.7 V respectively under the applied voltage of 25 V. After the switching of 1 × 1010 cycles, the Pr value decreases to 87% of its pre-fatigue values. The dielectric constant and the dielectric loss are about 204 and 0.024 at 1 kHz, respectively. The films show good insulating behaviour according to the test of leakage current. [ABSTRACT FROM AUTHOR]

Abstract: Ba0.6Sr0.4TiO3 (BST) thin films doped by K (0, 5, 10 and 12.5mol%) (BSTK) were deposited by radio frequency (RF) magnetron sputtering on Pt/Ti/SiO2/Si substrates. Atomic force microscopy and X-ray diffraction analysis were used to investigate the structure and morphology of the BST thin films. The dielectric measurements were conducted on metal–insulator–metal capacitors at the frequencies from 1kHz to 1MHz. It was found that the K concentration in BST thin films has a strong influence on the material properties including surface morphology, dielectric, and tunable properties. The surface root-mean-square roughness of the BSTK films decreased when 5mol% K was doped and increased with increasing content of K hereafter. The dielectric constant, dielectric loss and tunability increased when K was doped in the BSTK thin films. The (Ba0.6Sr0.4)95%K5%TiO3 thin film exhibited the highest tunability of dielectric constant of about 62.3% and a figure of merit of 26.1 at a maximum applied bias field at 1MHz. [Copyright &y& Elsevier]

One of the important monitoring indicators of the air pollution is atmospheric fine particulate matter (PM 2.5 ), which can induce lung inflammation after inhalation. Coelonin can alleviate PM 2.5 -induced macrophage damage through anti-inflammation. However, its molecular mechanism remains unclear. We hypothesized that macrophage damage may involve the release of inflammatory cytokines, activation of inflammatory pathways, and pyrosis induced by inflammasome. In this study, we evaluated the anti-inflammation activity of coelonin in PM 2.5 -induced macrophage and its mechanism of action. Nitric oxide (NO) and reactive oxygen species (ROS) production were measured by NO Assay kit and dichlorofluorescein-diacetate (DCFH-DA), and apoptosis were measured by Flow cytometry and TUNEL staining. The concentration of inflammatory cytokines production was measured with cytometric bead arrays and ELISA kits. The activation of NF-κB signaling pathway and NLRP3 inflammasome were measured by immunofluorescence, quantitative reverse transcription-polymerase chain reaction and western blot. As expected, coelonin pretreatment reduced NO production significantly as well as alleviated cell damage by decreasing ROS and apoptosis. It decreased generation of interleukin (IL)-6 and tumor necrosis factor (TNF)-α in PM 2.5 -induced RAW264.7 and J774A.1 cells. Moreover, coelonin markedly inhibited upregulating the expression of toll-like receptor (TLR)4 and cyclo-oxygenase (COX)-2, blocked activation of p-nuclear factor-kappa B (NF-κB) signaling pathway, and suppressed expression of NLRP3 inflammasome, ASC, GSDMD, IL-18 and IL-1β. In conclusion, the results showed that coelonin could protect against PM 2.5 -induced macrophage damage via suppressing TLR4/NF-κB/COX-2 signaling pathway and NLRP3 inflammasome activation in vitro., (© 2023 Wiley Periodicals LLC.)

Certain mutations in mitochondrial DNA (mtDNA) are associated with Leber's hereditary optic neuropathy (LHON). In particular, the well‑known NADH dehydrogenase 4 (ND4) m.11778G>A mutation is one of the most common LHON‑associated primary mutations worldwide. However, how specific mtDNA mutations, or variants, affect LHON penetrance is not fully understood. The aim of the current study was to explore the relationship between mtDNA mutations and LHON, and to provide useful information for early detection and prevention of this disease. Following the molecular characterization of a Han Chinese family with maternally inherited LHON, four out of eight matrilineal relatives demonstrated varying degrees of both visual impairment and age of onset. Through PCR amplification of mitochondrial genomes and direct Sanger sequencing analysis, a homoplasmic mitochondrial‑encoded ND4 m.11778G>A mutation, alongside a set of genetic variations belonging to human mtDNA haplogroup B5b1 were identified. Among these sequence variants, alanine transfer RNA (tRNA)Ala m.5601C>T was of particular interest. This variant occurred at position 59 in the TψC loop and altered the base pairing, which led to mitochondrial RNA (mt‑RNA) metabolism failure and defects in mitochondrial protein synthesis. Bioinformatics analysis suggested that the m.5601C>T variant altered tRNAAla structure. Therefore, impaired mitochondrial functions caused by the ND4 m.11778G>A mutation may be enhanced by the mt‑tRNAAla m.5601C>T variant. These findings suggested that the tRNAAla m.5601C>T variant might modulate the clinical manifestation of the LHON‑associated primary mutation.

In order to understand the difference of contents of coelonin,batatasin Ⅲ and 3'-O-methylbatatasin Ⅲ in 60 different sources of Bletilla striata planted under the same conditions. UPLC method was used and the analysis was performed on a Waters ACQUITY UPLC BEH C18 column( 2. 1 mm×100 mm,1. 7 μm),eluted with acetonitril-0. 1% formic acid solution by gradient. The flow rate was 0. 208 m L·min-1,the detection wavelength was 270 nm,the column temperature was 35 ℃ and the injection volume was 4μL. Under the above chromatographic conditions,the three components can be separated well with good linearity in the range of 0. 156-5. 000 mg·L-1. The average contents of coelonin,batatasin Ⅲ and 3'-O-methylbatatasin Ⅲ were( 0. 116 ± 0. 071) %,( 0. 386 ±0. 185) % and( 0. 086±0. 034) %,respectively. After planting for two years under the same conditions,there was no significant difference in chemical composition among different sources and varieties,but the contents of the three components had some regional differences,which indicated that the western region was higher than the eastern region,while the contents of coelonin and batatasin Ⅲ in B.sinensis were slightly higher than those in B. striata. The chromatographic method above is simple,stable and reproducible,and can be used for quantitative analysis of three components. The content analysis of different sources of B. striata can provide reference for future B. striata breeding and quality control.

Objective: To investigate the anti-pulmonary fibrosis effect and the possible molecular mechanism of the Bletilla striata polysaccharide., Methods: Polysaccharide was prepared by water reflux extraction plus ethanol precipitation method, and following deproteinization process by Sevage method. Rat silicosis model was established by invasive intratracheal instillation method. The effect and molecular mechanism of the polysaccharide was evaluated by lung indexes, lung pathological change, serum levels of SOD,MDA,NF-κB,IL-1β,PDGF,TGF-β1,TNF-α,HYP were detected, and the contents of CD3~+,CD4~+,CD8~+T lymph cells and CD4~+/ CD8~+ratio were detected by flow cytometry., Results: Both low( 100 mg / kg) and high( 400 mg / kg) dosage polysaccharide treatment could remarkably elevate the serum SOD level and reduce the MDA,NO level, and effectively reverse the CD4~+/ CD8~+ratio comparing with the model group( P < 0. 01). Except the TNF-α level was significantly lower in the high dosage treatment group, there was no other effect in inflammatory cytokines and HYP content in serum. HE pathological section confirmed that the Bletilla striata polysaccharide treatment group can not effectively prevent lung fibrosis., Conclusion: The Bletilla striata polysaccharide has remarkable regulation effect on antioxidation system and immune system, but can not effectively prevent lung fibrosis, more effort should be made to study the active antipulmonary fibrosis components of Bletilla striata.

Objective: To investigate the chemical constituents isolated from the fibrous roots of Bletilla striata, and to research their antibacterial activities., Methods: The native products were isolated and purified by silica gel, Sephadex LH-20 column chromatography and preparative HPLC. Their structures were elucidated on the basis of various spectroscopic analysis, and their antibacterial activities were tested by microbroth dilution method in a 96-well microtiter plate., Results: Seven compounds were isolated from the ethanol extract of the fibrous roots of Bletilla striata, and identified as p-hydroxybenzaldehyde( 1),2,7-dihydroxy-4-methoxy-9,10-dihydrophenanthrene( 2),4,5-dihydroxy-2-methoxy-9,10-dihydrohenanthrpene( 3),2-dihydroxy-4,7-dimethoxyphenan-threne( 4), militarine( 5), dactylorhin A( 6) and gastrodin( 7). Among them, compounds 2 ~ 4 showed moderate antibacterial activities against several Gram-positive bacterial strains( MIC 8 ~ 128 μg / m L),such as Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis and Bacillus subtilis., Conclusion: The fibrous roots and tubers of Bletilla striata contain similar compounds, including glucosyloxybenzyl 2-isobutylmalates,and phenanthrene compounds, which showed antimicrobial activities against Gram-positive bacterial strains. And compounds 3,4 are isolated from Bletilla genus for the first time.