Search

Inhalation represents a significant route of cadmium (Cd) exposure, which is associated with an elevated risk of lung diseases. This research study aims to evaluate the impact of repeated low-dose cadmium inhalation on exacerbating airway inflammation induced by ovalbumin (OVA) in asthma-afflicted mice. Mice were grouped into four categories: control (Ctrl), OVA, cadmium chloride (CdCl2), and OVA + cadmium chloride (OVA + CdCl2). Mice in the OVA group displayed increased airway mucus secretion and peribronchial and airway inflammation characterized by eosinophil cell infiltration, along with elevated levels of Th2 cytokines (IL-4, IL-5, IL-13) in bronchoalveolar lavage fluids (BALFs). These parameters were further exacerbated in the OVA + CdCl2 group. Additionally, the OVA + CdCl2 group exhibited higher levels of the oxidative stress marker malondialdehyde (MDA), greater activity of glutathione peroxidase (GSH-Px), and higher phosphorylation of extracellular regulated kinase (ERK) in lung tissue. Treatment with U0126 (an ERK inhibitor) and α-tocopherol (an antioxidant) in the OVA + CdCl2 group resulted in reduced peribronchial and airway inflammation as well as decreased airway mucus secretion. These findings indicate that CdCl2 exacerbates airway inflammation in OVA-induced allergic asthma mice following airway exposure. ERK and oxidative stress are integral to this process, and the inhibition of these pathways significantly alleviates the adverse effects of CdCl2 on asthma exacerbation. [ABSTRACT FROM AUTHOR]

Background: The pattern recognition receptor Dectin-1 was initially discovered to play a pivotal role in mediating pulmonary antifungal immunity and promoting neutrophil-driven inflammation. Recent studies have revealed that Dectin-1 is overexpressed in asthma, but the specific mechanism remains elusive. Additionally, Dectin-1 has been implicated in promoting pyroptosis, a hallmark of severe asthma airway inflammation. Nevertheless, the involvement of the non-classical pyroptosis signal caspase-11/4 and its upstream regulatory mechanisms in asthma has not been completely explored. Methods: House dust mite (HDM)-induced mice was treated with Dectin-1 agonist Curdlan, Dectin-1 inhibitor Laminarin, and caspase-11 inhibitor wedelolactone separately. Subsequently, inflammatory cells in bronchoalveolar lavage fluid (BALF) were analyzed. Western blotting was performed to measure the protein expression of caspase-11 and gasdermin D (GSDMD). Cell pyroptosis and the expression of chemokine were detected in vitro. The correlation between Dectin-1 expression, pyroptosis factors and neutrophils in the induced sputum of asthma patients was analyzed. Results: Curdlan appeared to exacerbate neutrophil airway inflammation in asthmatic mice, whereas wedelolactone effectively alleviated airway inflammation aggravated by Curdlan. Moreover, Curdlan enhanced the release of caspase-11 activation fragments and N-terminal fragments of gasdermin D (GSDMD-N) stimulated by HDM both in vivo or in vitro. In mouse alveolar macrophages (MH-S cells), Curdlan/HDM stimulation resulted in vacuolar degeneration and elevated lactate dehydrogenase (LDH) release. In addition, there was an upregulation of neutrophil chemokines CXCL1, CXCL3, CXCL5 and their receptor CXCR2, which was suppressed by wedelolactone. In asthma patients, a positive correlation was observed between the expression of Dectin-1 on macrophages and caspase-4 (the human homology of caspase-11), and the proportion of neutrophils in induced sputum. Conclusion: Dectin-1 activation in asthma induced caspase-11/4 mediated macrophage pyroptosis, which subsequently stimulated the secretion of chemokines, leading to the exacerbation of airway neutrophil inflammation. [ABSTRACT FROM AUTHOR]

This letter, proposes and experimentally demonstrates a simple and efficient estimating method for high‐voltage floating field ring (FFR). Four rings in FFR are used to determine the influence of rings' distance (d) on the voltage drops of the highest voltage to the third ring (Vn+1) and the third to the second ring (Vn). Then, two voltage curves (curves for Vn+1 and Vn) based on d are drawn. For a target breakdown voltage, by iterating between the curves for Vn+1 and Vn, the number of FFRs and corresponding distances can be found. Based on this method, an 8.0 kV PN diode with 111 FFRs is designed and fabricated. The measured breakdown voltage is 7840 V, which reaches 98% of the designed value. This method provides a simple and efficient design for high‐voltage SiC devices, especially for ultra‐high voltage applications where the number of rings exceeds dozens. [ABSTRACT FROM AUTHOR]

Inorganic arsenic (iAs) has been a human health concern and is associated with intestinal malignancies. However, the molecular mechanisms of the iAs‐induced oncogenic process in intestine epithelial cells remain elusive, partly because of the known hormesis effect of arsenic. Here, we established that six‐month exposure to iAs at a concentration similar to those found in contaminated drinking water could promote malignant characteristics, including enhanced proliferation and migration, resistance to apoptosis, and mesenchymal‐like transition in Caco‐2 cells. Transcriptome analysis and mechanism study revealed that key genes and pathways involved in cell adhesion, inflammation and oncogenic regulation were altered during chronic iAs exposure. Specifically, we uncovered that down‐regulation of HTRA1 was essential for the iAs‐induced acquisition of the cancer hallmarks. Further, we evidenced that the loss of HTRA1 during iAs‐exposure could be restored by HDAC6 inhibition. Caco‐2 cells with chronic exposure to iAs exhibited enhanced sensitivity to WT‐161, a specific inhibitor of HDAC6, when used alone than in combination with a chemotherapeutic agent. These findings provide valuable information for understanding the mechanisms of arsenic‐induced carcinogenesis and facilitating the health management of populations in arsenic‐polluted areas. This study explored the molecular mechanism associated with long‐term inorganic arsenic exposure in the colon epithelial Caco‐2 cell model. Our findings revealed that the down‐regulation of HTRA1 was essential for the malignant progression induced by chronic arsenic exposure, which could be restored by HDAC6 inhibition. These findings provide valuable information for understanding the key regulators of arsenic‐induced carcinogenesis. [ABSTRACT FROM AUTHOR]

In this work, the Polyurethane/MoS2 composites (PUM) filled with different amount of modified molybdenum disulfide (MoS2) were prepared by solution-blending-casting method. The thermal reversible Diels–Alder (DA) bonds enabled the polymer system recyclable ability. The modified MoS2 were obtained by tannic acid (TA) assistant ultra-sonication exfoliation method were used to improve the gas barrier performance of materials. Compared with the pure PU, about twofold decrease in oxygen gas permeability of PUM composites (from 6719 to 3927 cm3/m2˙d˙Pa) were obtained with 1 wt% MoS2. More important, the samples showed excellent gas barrier and mechanical properties before and after being hygrothermal aged for 100 h. The PUM composites had good gas barrier and recyclability and had great potential application prospects in packing materials. [ABSTRACT FROM AUTHOR]

DNA origami has been widely used to construct nanophotonic structures due to its unparallel capability in assembling photonic nanomaterials with nanometer precision. Nevertheless, the majority of fabricated fluorescence‐based nanophotonic systems so far operate in the ultraviolet‐visible (UV‐Vis) region, which are accompanied by limitations of shallow penetration and potential light damage. Herein, we constructed a reconfigurable nanophotonic heterostructure by integrating an upconversion nanoparticle (UCNP) and a gold nanorod (AuNR) on a DNA origami switch (DOS) template. With the unique anti‐Stokes luminescence of UCNP whose excitation wavelength is mostly located in the near‐infrared (NIR) region, the obtained reconfigurable nanophotonic system can be excited by 980 laser light and generates visible light emission. In our nanophotonic system, the DNA origami template serves as a switch to reversibly tune the optical properties of UCNP. The construction of this nanophotonic heterostructure expands the toolbox of DNA origami‐based nanophotonic systems that may hold great potential in optical biosensing and imaging. [ABSTRACT FROM AUTHOR]

Batteries dominate the market of electrochemical energy‐storage (EES) devices but suffer from low solid‐state ion‐diffusion kinetics. Herein, a facile strategy is presented to fabricate 2D Fe3O4 nanosheets with 3D hierarchically porous carbon (HPC) frameworks for high‐rate lithium‐ion batteries (LIBs) and sodium‐ion batteries (NIBs). These materials are achieved via a simple in situ ion–exchange process followed by a traditional carbonization–activation treatment, which is inspired by the ion intake and anchoring mechanisms of natural seaweeds. The resulting Fe3O4/HPC nanohybrids running at a high rate of 5 A g−1 can deliver high capacities of 418 and 144 mA h g−1 as the anodes of LIBs and NIBs, over 7.3 and 4.3 times those of their counterparts without porous structures. The Fe3O4/HPC also exhibits stable cycle life (≈114% and 93% retention after 1000 cycles at a high current density of 5 A g−1 for LIBs and NIBs, respectively), surpassing the most Fe3O4‐based batteries ever reported. This is attributed to the well‐controlled size of Fe3O4 nanosheets with the robust and interconnected 3D HPC frameworks that facilitate charge transport. Herein, a new strategy is provided to assemble 2D metal oxides onto a unique 3D architecture, generating electrodes for high‐performance EES devices. [ABSTRACT FROM AUTHOR]

Background: Monocytes are involved in tumor growth and metastasis, but the distribution of monocyte phenotypes and their role in the development of malignant pleural effusion (MPE) remains unknown. Methods: A total of 94 MPE patients (76 diagnosed with adenocarcinoma lung cancer and 18 with squamous cell lung cancer) and 102 volunteers for health examination in Xiangya Hospital from December 2016 to December 2019 were included in the study. Results: The distribution of monocyte subtypes identified by the expression of CD14 and CD16 were analyzed by flow cytometry. The proportion of CD14++CD16+ intermediate monocytes were significantly increased in pleural effusion of MPE patients. The complement system components were assayed by immunohistochemistry and ELISA, and higher expression of the classical and alternative pathways were detected in malignant pleural tissue. Transwell assay further revealed that C5a enhanced the infiltration of intermediate monocytes into the pleural cavity by promoting CCL2 production in pleural mesothelial cells (PMCs). In addition, C5a promoted the secretion of IL‐1β by intermediate monocytes. Furthermore, C5a activated in intermediate monocytes and IL‐1β released after C5a stimulation by monocytes promoted the proliferation, migration, adhesion, and epithelial‐to‐mesenchymal transition (EMT) of tumor cells, and attenuated tumor cell apoptosis. Conclusions: C5a, activated by the classical and alternative pathways of the complement system, not only mediated the infiltration of intermediate monocytes by enhancing CCL2 production in PMCs but also induced IL‐1β release from the recruited monocytes in MPE. The consequence of C5a activation and the subsequent IL‐1β overexpression in intermediate monocytes contributed to MPE progression. [ABSTRACT FROM AUTHOR]

DNA origami enables the manipulation of objects at nanoscale, and demonstrates unprecedented versatility for fabricating both static and dynamic nanostructures. In this work, we introduce a new strategy for transferring modular reconfigurable DNA nanostructures from two‐dimensional to three‐dimensional. A 2D DNA sheet could be modularized into connected parts (e.g. two, three, and four parts in this work), which can be independently transformed between two conformations with a few DNA "trigger" strands. More interestingly, the transformation of the connected 2D modules can lead to the controlled, resettable structural conversion of a 2D sheet to a 3D architecture, due to the constraints induced by the connections between the 2D modules. This new approach can provide an efficient mean for constructing programmable, higher‐order, and complex DNA objects, as well as sophisticated dynamic substrates for various applications. [ABSTRACT FROM AUTHOR]

This study was to test the hypothesis that root canal pretreated with photodynamic therapy (PDT) would promote stem cells from the apical papilla (SCAP) adhesion, proliferation and differentiation without affecting smear layer removal and microhardness of root canal. Standardized root canals were randomized into four groups (n = 30/group): (1) sodium hypochlorite(NaOCl) group, (2) NaOCl + ethylene diaminetetraacetic acid (EDTA) group, (3) NaOCl + PDT group, (4) NaOCl + EDTA + PDT group. After treatments, smear layer removal and microhardness of root canal were evaluated. SCAP with hydroxyapatite‐based scaffolds were seeded into root canals for 7 days. SCAP adhesion was observed by scanning electron microscope (SEM), and viable cells were calculated by CellTiter‐Glo Luminescent kit. Platelet‐derived growth factor (PDGF) and vascular endothelial growth factor (VEGF) expression of SCAP were evaluated by Quantitative Reverse Transcriptase‐Polymerase Chain Reaction. There was no significant difference in the smear layer removal and microhardness of root dentin between the groups with and without PDT treatment (P > 0.05). SCAP with elongated cytoplasmic processes and cell–cell contact were observed on the dentin surfaces treated with PDT. Elevated cell viability, PDGF and VEGF expression were found in root canal treated with PDT (P < 0.05). Under the experimental conditions, PDT could provide positive microenvironment for SCAP growth. [ABSTRACT FROM AUTHOR]

DNA‐modified lanthanide‐doped upconversion nanoparticles (DNA‐UCNPs) that combine the functions of DNA and the optical features of UCNPs have shown great promise in a wide range of fields. However, challenges remain in precisely tethering and orienting the DNA strands on the UCNP surface. Herein, we systematically investigate the sequence dependence of DNAs in their interactions with UCNPs, and reveal that poly‐cytosine (poly‐C) has high affinity for the UCNP surface. A general approach to synthesize monodispersed DNA‐UCNP conjugates is developed using poly‐C‐containing diblock DNA strands. The poly‐C segment of the DNA strand binds to the surfaces of UCNPs and the second segment is oriented perpendicularly on the UCNP surface, making the DNA‐UCNPs highly stable and monodispersed in aqueous solution. The dense layer of DNA on the UCNP surface enables the programmable assembly of UCNPs with other DNA‐functionalized nanoparticles or DNA origamis through hybridization, resulting in the formation of well‐organized complex structures. [ABSTRACT FROM AUTHOR]

In order to optimize the performances of the thermoacoustic refrigerator working with the high sound pressure level, the nonlinear acoustic characteristics of the thermoacoustic stack in the resonant pipe are studied. The acoustic fluid impedance of the stack made of copper mesh and set up in a resonant pipe is measured in the acoustic fields with different intensities. It is found that when the sound pressure level in the pipe increases to a critical value, the resistance of the stack increases nonlinearly with the sound pressure, while the reactance of the stack keeps constant. Based on the experimental results, a theory model is set up to describe the acoustic characteristics of the stack, according to the rigid frame theory and Forchheimmer equation. Furthermore, the influences of the sound pressure level, operating frequency, volume porosity, and length of the stack on the nonlinear impedance of the stack are evaluated. [ABSTRACT FROM AUTHOR]

The tubular acoustic metamaterial with the double negativity based on the membranes and side holes periodically distributed along a pipe is studied with the Bloch theory. The results are verified by the full-wave simulation method and are used to explain the related experimental phenomena: the low-frequency forbidden band starting from the zero Hertz and the relations between the cutoff frequencies of the forbidden and pass bands in the single negativity metamaterials and the double negativity metamaterial composed of them. Based on the Bloch theory, the structural parameters of the membranes and side holes in the metamaterial are optimized to achieve the maximum pass band with the negative phase velocity (PBNV) since the PBNV is determined by the coactions of the membranes and side holes. Furthermore, the structures of the metamaterials are improved in order to broaden the PBNV further and achieve the balanced condition simultaneously. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: Macrocycle has attracted the attention of many researchers in the field of medicinal chemistry due to its unique advantages and good prospects, but the difficulties in drug design and synthesis of macrocycle limit its applications. In this study, a series of macrocyclic derivatives designed from anaplastic lymphoma kinase (ALK) inhibitor lorlatinib were synthesized as Janus kinase 2 (JAK2) selective inhibitors. Among them, 17f had the best inhibitory activity (IC50 = 0.177 μmol·L–1) and selectivity for JAK2 over JAK1 and JAK3, which indicated that design of the macrocyclic derivatives might be a feasible strategy for the discovery of novel selective JAK2 inhibitors. [ABSTRACT FROM AUTHOR]

Various antimicrobial modalities have been proposed to treat peri‐implantitis but resulted in limited outcomes. The aim of this in vitro study was to evaluate the disinfection efficacy of combined application of chlorhexidine digluconate (CHX) and antimicrobial photodynamic therapy (aPDT) of titanium surfaces previously contaminated with Porphyromonas gingivalis biofilm. P. gingivalis biofilms were grown on 32 polished and 32 sandblasted large‐grit acid‐etched (SLA) titanium surfaces. Titanium disks were allocated into four groups as follows: (1) immersed in phosphate‐buffered saline (PBS), (2) immersed in 0.2% CHX, (3) application of aPDT and (4) immersed in 0.2% CHX and subsequent aPDT. Residual bacteria were determined by microbial culture analysis and by scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) imaging. Combination protocol (CHX+ aPDT) was the most effective in eradicating P. gingivalis (P < 0.05) on both polished and SLA surfaces. There was no significant difference in the number of remaining P. gingivalis between polished titanium disks and the SLA ones in four groups (P > 0.05). Under the limitation of this study, combined technique of preceding application of CHX and subsequent aPDT was shown to be an efficient method in reducing P. gingivalis numbers in both polished and SLA titanium surfaces. [ABSTRACT FROM AUTHOR]

Abstract Background S. aureus biofilm plays a predominant role in the establishment and development of peri-implantitis. It is suggested to combine different modalities as peri-implantitis treatment. The aim of this study was to evaluate the disinfection efficacy of combined application of antiseptics with PDT on Staphylococcus aureus (S. aureus) biofilm formed on titanium(Ti) disks with different surface roughness. Methods S. aureus biofilm was incubated on polished and sandblasted large-grit acid-etched (SLA) Ti surfaces for 48 h. 72 contaminated Ti disks (36 polished, 36 SLA) were randomly divided into 6 different groups as follows: (a) PBS, (b) 0.2% chlorhexidine digluconate (CHX), (c) 3% hydrogen peroxide (H 2 O 2), (d) PDT, (e) 0.2% CHX + PDT, and (f) 3% H 2 O 2 +PDT. Colony forming unit (CFU) was measured to determine antimicrobial effects. Biofilm structure was assessed using scanning electron microscopy (SEM) and confocal laser scanning microscope (CLSM). Results All disinfection methods significantly reduced bacteria amounts compared to control group on both polished and SLA Ti surfaces (P < 0.001). PDT demonstrated stronger decontamination ability in eliminating S. aureus from Ti surfaces than CHX and H 2 O 2 did (P < 0.05). The combined CHX or H 2 O 2 with PDT treatment were more effective in bacterial disinfection than a single administration of these treatments (P < 0.001). Conclusion The combination of CHX or H 2 O 2 administration with PDT was more effective in eradicating S. aureus on both polished and SLA Ti disks in comparison with either treatment alone, suggesting that combined usage of antiseptics with PDT could be a more efficient method for the treatment of peri-implantitis. [ABSTRACT FROM AUTHOR]

Background: To determine the prevalence of stress urinary incontinence (SUI) and associated factors in women with premature ovarian insufficiency (POI). Materials and Methods: The study included 149 patients with POI and 303 control women without POI. Age, body mass index (BMI), gestational history, time since onset of POI, and status of hormone therapy (HT) for POI were recorded. Results: There was no statistical difference in the mean age, BMI, and parity between the two groups. The prevalence of SUI in the POI group tended to be higher than that in the control group (20.9%, 30/149 vs. 16.2%, 49/303), although not significantly (p = 0.297). About 41.6% (62/149) of patients with POI received HT. Patients with POI and SUI were older (p = 0.018) and had higher BMI (p = 0.007) than women with POI without SUI (p = 0.007). Compared to nulliparas, primiparas were more likely to have SUI (p = 0.046). However, SUI developed irrespective of time since onset of oligomenorrhea/amenorrhea or HT use. Furthermore, regression analysis showed that the prevalence of SUI was higher in women 30–39 years of age (odds ratio [OR] = 3.27, p = 0.002) and older than 40 years (OR = 7.78, p = 0.001). Primiparas (OR = 2.89, p = 0.001) and vaginal delivery (OR = 2.58, p = 0.023) were associated with SUI. Conclusions: The prevalence of SUI was fairly high among patients with POI, and age, parity, and vaginal delivery were the main risk factors. However, duration of POI and HT use had no effect on SUI. Increasing awareness of the importance of urinary system health in this population will improve the quality of life for these women. [ABSTRACT FROM AUTHOR]

Studies have proved that large nonlinearities, fast responses, and broadband spectra are pre-requisites for designing materials with good optical limiting performance. Carbon nanotubes (CNTs) have shown promising optical limiting effects with the best performance at 532 nm. However CNTs can only be dissolved in limited types of solvents, such as chloroform, dichlorobenzene, and toluene, making their general processability an actual challenge. On the other hand, photon upconversion nanoparticles (UCNPs) have strong absorption in the near infrared (NIR) region, e.g., 980 nm. Thus, in situ synthesis of nanocomposites containing UCNPs and oxidized CNTs via coordination interactions would provide both solubility in water and good optical limiting behavior in the NIR region. Experimental results have indicated that the optical limiting performance of nanocomposites is better than that of either CNTs or UCNPs, which is reasonable due to synergistic effects. Luminescence decay studies of UCNPs have suggested that Förster resonance energy transfer is responsible for the good optical limiting performance under 980 nm laser illumination. [ABSTRACT FROM AUTHOR]

ABSTRACT A two-step direct melt copolymerization process of l-lactic acid ( L-LA)/glycolic acid (GA) was developed: poly( l-lactic acid) (PLLA) and poly(glycolic acid) (PGA) with different molecular weight was first synthesized respectively by binary catalyst (tin chloride/ p-toluenesulfonic or tin chloride); and then poly( l-lactic- co-glycolic acid) (b-PLGA) was produced by melt polymerization of the as-prepared PLLA and PGA, wherein the composition and chain structure of b-PLGA copolymers could be controlled by the molecular weight of PLLA. The chain structure and thermal properties of copolymers were studied by Wide-angle X-ray diffraction, nuclear magnetic resonance, differential scanning calorimetry, and thermogravimetric analysis. In comparison with the random PLGA (r-PLGA) synthesized by one-step direct melt polymerization, the average l-lactic blocks length ( LLA) in b-PLGA was longer while the average glycolic blocks length ( LGA) in b-PLGA was shorter which further resulted in the improved crystallinity and thermostability. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41566. [ABSTRACT FROM AUTHOR]