BMP3b Is a Novel Antifibrotic Molecule Regulated by Meflin in Lung Fibroblasts.

Fibroblasts play a central role in the lung fibrotic process. Our recent study identified a novel subpopulation of lung fibroblasts expressing meflin (mesenchymal stromal cell- and fibroblast-expressing Linx paralogue), antifibrotic properties of which were confirmed by murine lung fibrosis model. Meflin-expressing fibroblasts were resistant to fibrogenesis induced by TGF-ß (transforming growth factor-ß), but its underlying mechanisms remain unknown. In this study, evaluation of a silica-nanoparticle-induced lung fibrosis model confirmed the antifibrotic effect of meflin via the regulation of TGF-ß signaling. We conducted comparative gene expression profiling in lung fibroblasts, which identified growth differentiation factor 10 (Gdf10) encoding bone morphogenic protein 3b (BMP3b) as the most downregulated gene in meflin-deficient cells under the profibrotic condition with TGF-ß. We hypothesized that BMP3b can be an effector molecule playing an antifibrotic role downstream of meflin. As suggested by single-cell transcriptomic data, restricted expressions of Gdf10 (Bmp3b) in stromal cells including fibroblasts were confirmed. We examined possible antifibrotic properties of BMP3b in lung fibroblasts and demonstrated that Bmp3b-null fibroblasts were more susceptible to TGF-ß-induced fibrogenic changes. Furthermore, Bmp3b-null mice exhibited exaggerated lung fibrosis induced by silica-nanoparticles in vivo. We also demonstrated that treatment with recombinant BMP3B was effective against TGF-ß-induced fibrogenesis in fibroblasts, especially in the suppression of excessive extracellular matrix production. These lines of evidence suggested that BMP3b is a novel humoral effector molecule regulated by meflin which exerts antifibrotic properties in lung fibroblasts. Supplementation of BMP3B could be a novel therapeutic strategy for fibrotic lung diseases.

Fibroblasts positive for meflin have anti-fibrotic properties in pulmonary fibrosis.

The prognosis of elderly individuals with idiopathic pulmonary fibrosis (IPF) remains poor. Fibroblastic foci, in which aggregates of proliferating fibroblasts and myofibroblasts are involved, are the pathological hallmark lesions in IPF to represent focal areas of active fibrogenesis. Fibroblast heterogeneity in fibrotic lesions hampers the discovery of the pathogenesis of pulmonary fibrosis. Therefore, to determine the pathogenesis of IPF, identification of functional fibroblasts is warranted. The aim of this study was to determine the role of fibroblasts positive for meflin, identified as a potential marker for mesenchymal stromal cells, during the development of pulmonary fibrosis.We characterised meflin-positive cells in a single-cell atlas established by single-cell RNA sequencing (scRNA-seq)-based profiling of 243 472 cells from 32 IPF lungs and 29 normal lung samples. We determined the role of fibroblasts positive for meflin using bleomycin (BLM)-induced pulmonary fibrosis.scRNA-seq combined with in situ RNA hybridisation identified proliferating fibroblasts positive for meflin in fibroblastic foci, not dense fibrosis, of fibrotic lungs in IPF patients. A BLM-induced lung fibrosis model for meflin-deficient mice showed that fibroblasts positive for meflin had anti-fibrotic properties to prevent pulmonary fibrosis. Although transforming growth factor-ß-induced fibrogenesis and cell senescence with the senescence-associated secretory phenotype were exacerbated in fibroblasts via the repression or lack of meflin, these were inhibited in meflin-deficient fibroblasts with meflin reconstitution.These findings provide evidence to show the biological importance of meflin expression on fibroblasts and myofibroblasts in the active fibrotic region of pulmonary fibrosis.

Size and surface modification of silica nanoparticles affect the severity of lung toxicity by modulating endosomal ROS generation in macrophages.

BACKGROUND: As the application of silica nanomaterials continues to expand, increasing chances of its exposure to the human body and potential harm are anticipated. Although the toxicity of silica nanomaterials is assumed to be affected by their physio-chemical properties, including size and surface functionalization, its molecular mechanisms remain unclear. We hypothesized that analysis of intracellular localization of the particles and subsequent intracellular signaling could reveal a novel determinant of inflammatory response against silica particles with different physico-chemical properties. RESULTS: We employed a murine intratracheal instillation model of amorphous silica nanoparticles (NPs) exposure to compare their in vivo toxicities in the respiratory system. Pristine silica-NPs of 50 nm diameters (50 nm-plain) induced airway-centered lung injury with marked neutrophilic infiltration. By contrast, instillation of pristine silica particles of a larger diameter (3 µm; 3 µm-plain) significantly reduced the severity of lung injury and neutrophilic infiltration, possibly through attenuated induction of neutrophil chemotactic chemokines including MIP2. Ex vivo analysis of alveolar macrophages as well as in vitro assessment using RAW264.7 cells revealed a remarkably lower cellular uptake of 3 µm-plain particles compared with 50 nm-plain, which is assumed to be the underlying mechanism of attenuated immune response. The severity of lung injury and neutrophilic infiltration was also significantly reduced after intratracheal instillation of silica NPs with an amine surface modification (50 nm-NH2) when compared with 50 nm-plain. Despite unchanged efficacy in cellular uptake, treatment with 50 nm-NH2 induced a significantly attenuated immune response in RAW264.7 cells. Assessment of intracellular redox signaling revealed increased reactive oxygen species (ROS) in endosomal compartments of RAW264.7 cells treated with 50 nm-plain when compared with vehicle-treated control. In contrast, augmentation of endosomal ROS signals in cells treated with 50 nm-NH2 was significantly lower. Moreover, selective inhibition of NADPH oxidase 2 (NOX2) was sufficient to inhibit endosomal ROS bursts and induction of chemokine expressions in cells treated with silica NPs, suggesting the central role of endosomal ROS generated by NOX2 in the regulation of the inflammatory response in macrophages that endocytosed silica NPs. CONCLUSIONS: Our murine model suggested that the pulmonary toxicity of silica NPs depended on their physico-chemical properties through distinct mechanisms. Cellular uptake of larger particles by macrophages decreased, while surface amine modification modulated endosomal ROS signaling via NOX2, both of which are assumed to be involved in mitigating immune response in macrophages and resulting lung injury.

Effects of Polypropylene Glycol at Very Low Concentrations on Rheological Properties at the Air-Water Interface and Foam Stability of Sodium Bis(2-ethylhexyl)sulfosuccinate Aqueous Solutions.

The present study investigates the effects of very low concentrations of polypropylene glycol (PPG) on the rheological properties of sodium bis(2-ethylhexyl)sulfosuccinate (AOT) aqueous solutions at the surface for the precise control of foam properties. Langmuir trough experiments and Brewster angle microscopy (BAM) of the AOT monolayer on the surfaces of PPG aqueous solutions indicated that a very low concentration of PPG increased the number of AOT molecules at the surface. Viscoelastic behaviors at the surface and surface tension isotherms in mixed aqueous solutions of AOT and PPG revealed that AOT interacted with PPG in the surface and bulk phase. A modified Ross-Miles method was performed to assess the foam stabilities of AOT aqueous solutions with and without PPG. The stabilization of foam by PPG was attributed to the rheological properties of AOT aqueous solutions at the surface.

Repressive role of stabilized hypoxia inducible factor 1α expression on transforming growth factor ß-induced extracellular matrix production in lung cancer cells.

Activation of transforming growth factor ß (TGF-ß) combined with persistent hypoxia often affects the tumor microenvironment. Disruption of cadherin/catenin complexes induced by these stimulations yields aberrant extracellular matrix (ECM) production, characteristics of epithelial-mesenchymal transition (EMT). Hypoxia-inducible factors (HIF), the hallmark of the response to hypoxia, play differential roles during development of diseases. Recent studies show that localization of cadherin/catenin complexes at the cell membrane might be tightly regulated by protein phosphatase activity. We aimed to investigate the role of stabilized HIF-1α expression by protein phosphatase activity on dissociation of the E-cadherin/ß-catenin complex and aberrant ECM expression in lung cancer cells under stimulation by TGF-ß. By using lung cancer cells treated with HIF-1α stabilizers or carrying doxycycline-dependent HIF-1α deletion or point mutants, we investigated the role of stabilized HIF-1α expression on TGF-ß-induced EMT in lung cancer cells. Furthermore, the underlying mechanisms were determined by inhibition of protein phosphatase activity. Persistent stimulation by TGF-ß and hypoxia induced EMT phenotypes in H358 cells in which stabilized HIF-1α expression was inhibited. Stabilized HIF-1α protein expression inhibited the TGF-ß-stimulated appearance of EMT phenotypes across cell types and species, independent of de novo vascular endothelial growth factor A (VEGFA) expression. Inhibition of protein phosphatase 2A activity abrogated the HIF-1α-induced repression of the TGF-ß-stimulated appearance of EMT phenotypes. This is the first study to show a direct role of stabilized HIF-1α expression on inhibition of TGF-ß-induced EMT phenotypes in lung cancer cells, in part, through protein phosphatase activity.

Crystallite Size Increase of Silver Nanoparticles by Ligand Exchange and Subsequent Washing Process with Antisolvent.

Desorption performance of ligands from silver nanoparticles extremely affects a sintering process of nanoinks for their writing fine pattern. In this study, we investigated desorption behaviors of ligands on the surface of silver nanoparticle through ligand exchange and subsequent washing process with antisolvent. Ligand exchange reactions from oleic acid to tri-n-octylphosphine oxide (TOPO), octanoic acid (OA), and 1-dodecanethiol (DDT) were carried out on the surface of silver nanoparticle. After the washing process with methanol as an antisolvent, their crystallite sizes and the amounts of ligands existing on the particle surface were evaluated by powder X-ray diffraction and thermogravimetric analysis, respectively. In the case of ligand exchange with TOPO, the crystallite size dramatically increased and the amount of ligands existing on the particle surface significantly decreased. This result shows that TOPO is easy to desorb from the silver surface in the washing process with methanol, which resulted in the efficient coalescence of silver. In contrast, the coalescence of silver nanoparticles capped with OA and DDT was less efficient. Moreover, the effect of the antisolvent in the washing process on the coalescence of silver was demonstrated in detail.

BK virus-associated viruria and viremia in a patient with lymphangioleiomyomatosis after lung re-transplantation: A case report and review of the literature on BK virus infection post-lung transplantation.

The BK virus (BKV) is a member of the polyomaviridae family of DNA viruses. BKV reactivates under a highly immunosuppressed state and causes renal dysfunction. In renal transplant patients, BKV infection leads to tubular impairment and loss of transplanted kidney grafts. However, few studies have reported on the relationship between BKV and lung transplantation. Adjustment of the dosage of immunosuppressants is needed in some cases, but the treatment method has not been established. Here, we report a case of BKV-associated viruria and viremia in a patient with lymphangioleiomyomatosis (LAM) after lung re-transplantation. A 44-year-old female refractory LAM patient who had undergone lung re-transplantation 3 months earlier was diagnosed with BKV-associated viruria and viremia. Urine cytology indicated decoy cells and the urine and serum polymerase chain reaction test was positive for BKV. As scheduled after re-transplantation surgery, immunosuppressive drugs were progressively reduced. This patient was considered to have experienced spontaneous BKV-associated viremia and viruria. Review of the literature suggested that 17%-42% of BKV-associated viruria cases have been reported after lung transplantation, but cases of BKV-associated nephropathy are rarely reported. Based on the present case, doctors involved in lung transplantation should monitor patients for BKV infection. Decoy cell monitoring by urine cytology is a useful screening method in the follow-up observation after lung transplantation. Early-stage interventions may prevent BKV-associated nephropathy even in patients who have developed BKV viremia, and sirolimus can be administered to patients with histories of BKV infection if they are carefully monitored.

Effect of Protective Agents on Silver Nanoparticle Preparation by Vacuum Evaporation on Running Hydrocarbon Solution.

In order to simply compare the performance of protective agents in the preparation of metal nanoparticles, a systematic investigation based on the same synthetic conditions is necessary. We successfully achieved this objective using improved vacuum evaporation on running oil substrate (VEROS) method. The efficient synthesis of nanoparticles with the improved VEROS method enabled us to characterize them by various analytical methods. In this study, five types of protective agents with different functional groups were employed to clarify their effect on the preparation of silver nanoparticles. They are sorbitan monooleate, oleylamine, oleic acid, oleyl alcohol, and methyl oleate. Particles synthesized by the improved VEROS method were evaluated by transmission electron microscope (TEM) and UV-vis spectrophotometer. These results indicate that sorbitan monooleate and oleic acid effectively protect the aggregation between particles. It is also evident from the evaluation of powdered nanoparticles isolated from the trap solution by thermogravimetric analysis (TGA) that these protective agents adsorb on the surface of the particles. On the other hand, the aggregates of silver nanoparticles were formed in the cases using oleic alcohol and methyl oleate. Silver nanoparticles were obtained in the case of oleylamine but the material efficiency of silver was extremely low. As a result, our systematic investigation using the improved VEROS method disclosed suitable protective agents in the preparation of silver nanoparticles with the physical method.

Exercise hypoxaemia as a predictor of pulmonary hypertension in COPD patients without severe resting hypoxaemia.

BACKGROUND AND OBJECTIVE: Pulmonary hypertension (PH) in COPD is associated with morbidity and mortality. Previous studies showed a relationship between resting hypoxaemia and PH, but little is known about the relationship between exercise hypoxaemia and PH in COPD without resting hypoxaemia. METHODS: A retrospective observational study of COPD patients without resting hypoxaemia was conducted to evaluate the relationships between exercise hypoxaemia and pulmonary haemodynamics. Clinical characteristics, pulmonary function, blood gas analysis, 6-min walk distance (6MWD) and oxygen saturation of peripheral artery (SpO2 ) at the end of the 6-min walk test (6MWT) were reviewed. Correlation analysis and stepwise regression analysis were performed to identify the predictor of mean pulmonary artery pressure (mPAP). RESULTS: Eighty-four consecutive patients with a mean predicted forced expiratory volume in 1 s (FEV1 ) of 47 ± 21% were evaluated. In univariate analysis, mPAP had negative correlations with age (r = -0.27, P < 0.05), arterial partial pressure of oxygen (PaO2 , r = -0.24, P < 0.05), % predicted forced vital capacity (FVC, r = -0.28, P < 0.05), % predicted FEV1 (r = -0.40, P < 0.001), FEV1 /FVC ratio (r = -0.33, P < 0.005), % predicted diffusion capacity for carbon monoxide (DLCO , r = -0.40, P < 0.001), 6MWD (r = -0.40, P < 0.001) and SpO2 at the end of the 6MWT (r = -0.74, P < 0.001). In stepwise regression analysis, SpO2 at the end of the 6MWT and 6MWD remained as independent predictors of mPAP (R2 = 0.60). In receiver operating characteristic (ROC) analysis, SpO2 at the end of the 6MWT presented an area under the curve of 0.896 for the prediction of PH, with a sensitivity of 0.86 and specificity of 0.84 for the cut-off point of 81%. CONCLUSION: In addition to 6MWD, exercise hypoxaemia indicates PH in patients with COPD without resting hypoxaemia.

High-Mobility 6,13-Bis(triisopropylsilylethynyl) Pentacene Transistors Using Solution-Processed Polysilsesquioxane Gate Dielectric Layers.

Polysilsesquioxane (PSQ) is a low-temperature curable polymer that is compatible with low-cost plastic substrates. We cured PSQ gate dielectric layers by irradiation with ultraviolet light at ~60 °C, and used them for 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS-pentacene) thin film transistors (TFTs). The fabricated TFTs have shown the maximum and average hole mobility of 1.3 and 0.78 ± 0.3 cm2V-1s-1, which are comparable to those of the previously reported transistors using single-crystalline TIPS-pentacene micro-ribbons for their active layers and thermally oxidized SiO2 for their gate dielectric layers. Itis therefore demonstrated that PSQ is a promising polymer gate dielectric material for low-cost organic TFTs.

Investigation of Ultraviolet Light Curable Polysilsesquioxane Gate Dielectric Layers for Pentacene Thin Film Transistors.

Polysilsesquioxane (PSQ) comprising 3-methacryloxypropyl groups was investigated as an ultraviolet (UV)-light curable gate dielectric-material for pentacene thin film transistors (TFTs). The surface of UV-light cured PSQ films was smoother than that of thermally cured ones, and the pentacene layers deposited on the UV-Iight cured PSQ films consisted of larger grains. However, carrier mobility of the TFTs using the UV-light cured PSQ films was lower than that of the TFTs using the thermally cured ones. It was shown that the cross-linker molecules, which were only added to the UV-light cured PSQ films, worked as a major mobility-limiting factor for the TFTs.

A single-molecule force-spectroscopic study on stabilization of G-quadruplex DNA by a telomerase inhibitor.

Single-molecule force spectroscopy was carried out using AFM force measurements for the purpose of direct observation of the stabilization of G-quadruplex DNA by a telomerase inhibitor, which is 5,10,15,20-tetrakis(N-methylpyridinium-4-yl)porphyrin tetrakis(p-toluenesulfonate) (TMPyP). In AFM force measurements, we used an AFM tip and an Au substrate modified chemically with terminal-biotinylated telomere DNA and streptavidin, respectively. The telomere DNA was fully stretched by the AFM tip based on the bridge formation between the AFM tip and the Au substrate through the streptavidin-biotin interaction. The force-extension curves, which reflected the stretching of a single DNA molecule, were distinguished from all of the curves, judging from the rupture force and the contour length. The selected curves were analyzed using a worm-like chain model, and one of the fitting parameters, persistence length (lp), was used as an index for the stabilization of the G-quadruplex structure. Consequently, the lp value was significantly increased by the addition of TMPyP under the experimental conditions where the G-quadruplex structure could be formed. On the other hand, the value was hardly changed by the addition of TMPyP under the conditions except the above. Furthermore, the methodology developed and demonstrated in this work was applied to evaluate the stabilization of G-quadruplex DNA by other telomerase inhibitors such as ethidium bromide and p-xylene-bis(N-pyridinium bromide).

Polydopamine-Coated Solid Silica Nanoparticles Encapsulating IR-783 Dyes: Synthesis and NIR Fluorescent Cell Imaging.

We report a simple and efficient synthetic method for polydopamine (PDA)-coated solid silica nanoparticles (s-SiO2@PDA NPs) encapsulating anionic near-infrared (NIR) fluorescent dyes through physical adsorption. Despite the use of anionic NIR fluorescent dyes indocyanine green (ICG) and 2-[2-[2-chloro-3-[2-[1,3-dihydro-3,3-dimethyl-1-(4-sulfobutyl)-2H-indol-2-ylidene]-ethylidene]-1-cyclohexen-1-yl]-ethenyl]-3,3-dimethyl-1-(4-sulfobutyl)-3H-indolium (IR-783), they were successfully immobilized on anionic s-SiO2@PDA NP surfaces under acidic aqueous conditions. After embedding in the s-SiO2@PDA NPs, the fluorescence of ICG was almost quenched, while a diminished IR-783 fluorescence remained observable. The fluorescence intensity of IR-783 embedded in s-SiO2@PDA NPs remained almost constant over 2 weeks in a pseudobiological solution, with a slight reduction due to dye degradation and dye leakage from the s-SiO2@PDA NPs. Finally, the s-SiO2@PDA NPs encapsulating IR-783 were successfully used for NIR fluorescent imaging of African green monkey kidney cells.

Ultra-high-sensitive extraction-photometric determination of sodium ion using flow injection analysis with a chromogenic calix[4]arene derivative and a laser interferometric photothermal detector.

A novel flow injection analysis (FIA) system for ultra-high-sensitive determination of Na(+), which involves laser interferometric photothermal equipment as the detector, was designed using a proton-dissociable chromogenic calix[4]arene derivative with a dinitrophenol moiety as the extraction-photometric reagent. The chromogenic calix[4]arene derivative showed an excellent extractability toward Na(+), which reflected the cation-complexing property of the tetraethyl ester derivative of calix[4]arene. As the calibration graph of the Na(+) concentration could be successfully obtained at the nanomolar level by this method, the proposed FIA system was found to be promising for highly sensitive determination of Na(+) in very dilute samples such as supply water and cooling water in power plants.

Room-temperature coalescence of Pd nanoparticles with sacrificial templates and sintering agents, and their catalytic activities in the Suzuki coupling reaction.

Porous metal structures are very useful for heterogeneous catalysts in organic syntheses. This study reports a novel method to fabricate porous Pd structures by room-temperature (RT) coalescence of Pd nanoparticles (Pd NPs). First, oleylamine-capped Pd NPs were synthesized, and then Pd NP pastes were fabricated by mixing with tri-n-octylphosphine oxide as a sacrificial template. Finally, the Pd NP paste was dipped into methanol containing a sintering agent. When KOH was used as the sintering agent, porous Pd structures could be successfully obtained at RT. The catalytic activities of porous Pd structures were investigated in the Suzuki coupling reaction and they increased with the increase of the KOH concentration in the sintering process. These results indicate that pre-activation of porous Pd structures by KOH increased the catalytic activities.

Synthesis of Silica Nanoparticles with Physical Encapsulation of Near-Infrared Fluorescent Dyes and Their Tannic Acid Coating.

This study reports a novel method for the synthesis of silica nanoparticles (NPs) encapsulating near-infrared (NIR) fluorescent dyes through physical adsorption. Although a NIR cationic fluorescent dye, oxazine 725 (OXA), has no chemical bonding moiety toward silica NPs such as the triethoxysilyl group, the dyes were successfully incorporated into silica NPs without denaturation under the mild reaction conditions. Next, tannic acid (TA) molecules were coated in the presence of Fe3+ on the particle surface for the functionalization of silica NPs encapsulating OXA (OXA@SiO2 NPs). The TA coating on the surface of OXA@SiO2 NPs was confirmed by transmission electron microscopy and X-ray photoelectron spectroscopy. The TA coating significantly contributed to the resistance improvement against photobleaching and leakage of the dyes in the NPs. Furthermore, the obtained TA-coated silica NPs encapsulating OXAs (OXA@SiO2@TA NPs) were used for the fluorescence imaging of African green monkey kidney (COS-7) cells, and it was shown that the fluorescence originated from OXA@SiO2@TA NPs was clearly observed in the COS-7 cells.

Morphological changes in vesicles and release of an encapsulated compound triggered by a photoresponsive Malachite Green leuconitrile derivative.

Photoinduced morphological changes in phosphatidylcholine vesicles are triggered by a Malachite Green leuconitrile derivative dissolved in the lipidic membrane, and are observed at Malachite Green derivative/lipid ratios <5 mol %. This Malachite Green derivative is a photoresponsive compound that undergoes ionization to afford a positive charge on the molecule by UV irradiation. The Malachite Green derivative exhibits amphiphilicity when ionized photochemically, whereas it behaves as a lipophilic compound under dark conditions. Cryo-transmission electron microscopy was used to determine vesicle morphology. The effects of the Malachite Green derivative on vesicles were studied by dynamic light scattering and fluorescence resonance energy transfer. Irradiation of vesicles containing the Malachite Green derivative induces nonspherical vesicle morphology, fusion of vesicles, and membrane solubilization, depending on conditions. Furthermore, irradiation of the Malachite Green derivative induces the release of a vesicle-encapsulated compound.

High-flow nasal cannula therapy for acute respiratory failure in patients with interstitial pneumonia: a retrospective observational study.

High-flow nasal cannula (HFNC) oxygen is a therapy that has demonstrated survival benefits in acute respiratory failure (ARF). However, the role of HFNC in ARF due to interstitial pneumonia (IP) is unknown. The aim of this study was to compare the effects of HFNC therapy and non-invasive positive pressure ventilation (NPPV) in ARF due to IP. This retrospective observational study included 32 patients with ARF due to IP who were treated with HFNC (n = 13) or NPPV (n = 19). The clinical characteristics, intubation rate and 30-day mortality were analyzed and compared between the HFNC group and the NPPV group. Predictors of 30-day mortality were evaluated using a logistic regression model. HFNC group showed higher mean arterial blood pressure (median 92 mmHg; HFNC group vs 74 mmHg; NPPV group) and lower APACHEII score (median 22; HFNC group vs 27; NPPV group) than NPPV group. There was no significant difference in the intubation rate at day 30 between the HFNC group and the NPPV group (8% vs 37%: p = 0.069); the mortality rate at 30 days was 23% and 63%, respectively. HFNC therapy was a significant determinant of 30-day mortality in univariate analysis, and was confirmed to be an independent significant determinant of 30-day mortality in multivariate analysis (odds ratio, 0.148; 95% confidence interval, 0.025-0.880; p = 0.036). Our findings suggest that HFNC therapy can be a possible option for respiratory management in ARF due to IP. The results observed here warrant further investigation of HFNC therapy in randomized control trials.