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Micro/nano-textured Si wafers manufactured using metal-assisted chemical etching (MACE) have been the focus of several studies, but the mechanism of bubble generation during the MACE process affecting textured surfaces has rarely been reported. This study investigated the bubble effect due to the different placement patterns of the Si wafer (face-up, stirred face-down, and face-down). The results indicated that the placement pattern of the Si wafer notably influences the uniformity of outward appearance. At 2 h of etching, the outward appearance uniformity of face-up etching was more homogeneous than that of stirred face-down and face-down patterns, and the Si nanowires (SiNWs) processed through face-up etching were longer (41 μm) than those subjected to stirred face-down etching (36 μm) and face-down etching (32 μm). Therefore, the placement pattern of Si wafer can affect the uniformity and properties of SiNWs because of bubbles trapped inside cavities or between SiNWs.

To investigate the efficacy of high-frequency oscillatory ventilation (HFOV) combined with pulmonary surfactant (PS) in the treatment of neonatal respiratory distress syndrome (NRDS).This study is a retrospective clinical study. Seventy-two NRDS neonates were selected as the subjects from November 2019 to November 2020, and divided into observation group (40 cases, HFOV treatment) and control group (32 cases, conventional mechanical ventilation treatment). All cases were treated with PS and comprehensive treatment. The therapeutic effect, arterial partial pressure of oxygen (PaO2), arterial partial pressure of carbon dioxide (PaCO2), Percentage of inhaled oxygen concentration (FiO2), mean arterialpressure, oxygenation index (OI), and complications were compared in the 2 groups.The total effective rate of the observation group was 90.0%, significantly higher than that of the control group. After treatment, the observation group has higher PaO2 levels and lower levels of PaCO2, mean arterial pressure, FiO2, and OI than the control group. There was no significant difference in the incidence of complications between the 2 groups.HFOV combined with PS has a significant effect on NRDS, which can improve the arterial blood gas index without increasing the incidence of complications.

The source of metal and sulphur in porphyry and related epithermal deposits is a long debated issue. The role of mantle-derived magmas in providing the metals has proved particularly problematic. Here we report new He and Ar isotope determinations from ore fluids from the Zijinshan high sulfidation-epithermal Cu-Au deposit and Wuziqilong transitional Cu deposit from the giant Zijinshan porphyry-epithermal Cu-Au-Mo-Ag ore system (from 105 to 91 Ma), to decipher the contribution of mantle-derived volatiles and heat. Hydrothermal fluids in pyrite and digenite have 3He/4He up to 5.7 Ra, among the highest measured in ancient ore-forming fluids. A linear correlation between He and Ar isotopes indicate that the ore fluids were, to a first order, a mixture between a shallow crustal fluid, with low 3He/4He, and a dominantly mantle-derived fluid with high 3He/4He. The mantle 3He/4He is close to values typical of the upper mantle indicating the initial magmas that provided the heat for hydrothermal systems did not assimilate large volumes of continental crust. The ore-forming fluids have 3He/heat ratios that are 10 to 80 times higher than that of mid-oceanic ridge hydrothermal fluids, indicating that the metal-bearing fluids acquired heat and volatiles in a convective, rather than conductive, hydrothermal regime. It appears that mantle-derived volatiles, heat and probably metals have made a major contribution to the Cu-Au-Mo-Ag mineralization in the Zijinshan orefield.

The giant sediment-hosted Jinding zinc-lead deposit is located in the Lanping Basin, northwestern Yunnan Province, China. The genesis of the deposit has long been debated and the sources of the ore-forming fluids and metals are controversial. This study presents rare earth element (REE) and noble gas isotope data that constrain the origins of the ore fluids and the heat source driving the hydrothermal circulation. The early-stage sulfides are enriched in light REEs and have high ∑REE values (30.8–94.8 ppm) and weakly negative Eu (δEu 0.85–0.89) and Ce anomalies (δCe 0.84–0.95), suggesting that the fluids were likely derived from dissolution of Upper Triassic marine carbonates with input of REEs from aluminosilicate rocks in the basin. In contrast, the late-stage sulfides have irregular REE patterns, generally low ∑REE values (0.24–10.8 ppm) and positive Eu (δEu 1.22–10.9) and weakly negative Ce anomalies (δCe 0.53–0.90), which suggest that the ore-forming fluids interacted with evaporite minerals. The 3 He/ 4 He (0.01–0.04 R a ) and 40 Ar/ 36 Ar values (301–340) of the ore-forming fluids indicate crustal and atmospheric origins for these noble gases. These findings are in agreement with the published fluid inclusion microthermometry data and the results of H, O, C, S, Pb and Sr isotope studies. Our data, in combination with published results, support a two-stage hydrothermal mineralization model, involving early-stage basinal brines and late-stage meteoric water that acquired metals and heat from crustal sources.

The Zijinshan high-sulfidation epithermal Cu–Au deposit is located in the Zijinshan ore field of South China, comprising porphyry–epithermal Cu–Au–Mo–Ag ore systems. The Cu ore body is more than 1000 m thick and is characterized by an assemblage of digenite–covellite–enargite–alunite. Digenite is the dominant Cu-bearing mineral, which makes this deposit unique, although the mechanisms of digenite formation remain controversial. To elucidate the genesis of digenite, this paper presents the Cu isotopic compositions of Cu-sulfides in the Zijinshan high-sulfidation Cu–Au deposit. The Cu isotopic values (65Cu relative to NIST 976) of all samples range from −2.97‰ to +0.34‰, and most values fall in a narrow range from −0.49‰ to +0.34‰, which is similar to the Cu isotopic signature of typical porphyry systems. Copper isotope ratios of each mineral decrease with increasing depth, a trend that is also typical of porphyry deposits. The variation tendency of δ65Cu values between sulfides is consistent with the sequence of mineral formation. These observations suggest that the Cu-sulfides in the Zijinshan Cu–Au deposit have a hypogene origin.

In this paper, a novel approach using HPLC-MS/MS (high performance liquid chromatography-tandem mass spectrometry) was established for the identification of Pericarpium Citri Reticulatae (PCR). The identities of the components were researched by comparing the mass spectra and retention times with those of reference compounds and mass fragments with those of the known compounds published in literature. Based on the proposed strategy, ten constituents were identified. The established HPLC-MS/MS method could identify the major constituents in PCR with high efficiency and sensitivity. The new method would be suitable for the chemical identification of main components from Pericarpium Citri Reticulatae.

The Lanping basin, Yunnan province, SW China, is located at the juncture of the Eurasian and Indian Plates in the eastern part of the Tibetan Plateau. The Lanping basin, in the Sanjiang Tethyan metallogenic province, is a significant Cu–Ag–Zn–Pb mineralized belt in China that includes the largest sandstone-hosted Zn–Pb deposit in the world, the Jinding deposit, as well as several Ag–Cu deposits (the Baiyangping and Jinman deposits). These deposits, with total reserves of over 16.0 Mt Pb + Zn, 0.6 Mt Cu, and 7,000 t Ag, are mainly hosted in Meso-Cenozoic clastic rocks and are dominantly controlled by two Cenozoic thrust systems developed in the western and eastern segments of the basin. The Baiyangping, Babaoshan, and Hetaoqing ore deposits are representative of the epithermal base metal deposits in the Lanping basin. The microthermometric data show that the ore-forming fluids for these deposits were low temperature (110–180 °C) and had bimodal distribution of salinity at moderate and mid to high salinities (approximately 2–8 wt.% and 18–26 wt.% NaCl equivalent). The C and O isotope data indicate that the ore-forming fluids were related to hot basin brines. We present new He and Ar isotope data on volatiles released from fluid inclusions contained in sulfides and in barite in these three deposits. 3He/4He ratios of the ore-forming fluids are 0.01 to 0.14 R/Ra with a mean of 0.07 Ra (where R is the 3He/4He ratio and Ra is the ratio for atmospheric helium). This mean value is intermediate to typical 3He/4He ratios for the crust (R/Ra = 0.01 to 0.05) and the ratio for air-saturated water (R/Ra = 1). The mean ratio is also significantly lower than the ratios found for mantle-derived fluids (R/Ra = 6 to 9). The 40Ar/36Ar ratios of the ore-forming fluids range from 298 to 382 with a mean of 323. This value is slightly higher than that for the air-saturated water (295.5). The 3He/4He ratios of fluids from the fluid inclusions imply that the ore-forming fluid for the Baiyangping, Babaoshan, and Hetaoqing deposits was derived from the crust and that any mantle-derived He was negligible. The content of the radiogenic Ar ranges between 0.2 to 20.4%, and the proportion of air-derived 40Ar averages 94.1%. This indicates that atmospheric Ar was important in the formation of these deposits but that some radiogenic 40Ar was derived from crustal rocks. Based on these observations coupled with other geochemical evidence, we suggest that the ore-forming fluids responsible for the formation of the Ag–Cu–Pb–Zn polymetallic ore deposits in the Baiyangping area of the Lanping basin were mainly derived from crustal fluids. The fluids may have mixed with some amount of air-saturated water, but there was no significant involvement of mantle-derived fluids.

The Jinding Zn–Pb deposit, located in the Lanping basin in Northwest Yunnan Province, is the largest Zn–Pb deposit in China, and also probably the youngest sediment-hosted super giant Zn–Pb deposit in the world. Its genesis differs from the well-known major types of sediment-hosted Zn–Pb deposits. Based on mineral paragenesis and textures, there are two stages of mineralization: stage 1 that is typically characterized by fine-grained sulfide minerals (galena, sphalerite, pyrite and marcasite) disseminated in sandstones of the Lower Cretaceous Jingxing Formation (K 1 j), and massive sulfides in limestone breccias of the Paleocene Yunlong Formation (E 1 y); and stage 2 which mainly occurs as coarse-grained galena veins crosscutting stage 1 sulfides, and minor amounts of colloform sphalerite intergrown with galena. In situ sulfur isotopic analyses of galena, sphalerite and pyrite were determined by secondary ion mass spectrometry (SIMS), and showed highly variable δ 34 S values (− 42.1‰–7.7‰) of different ore types. Stage 1 mineralization has δ 34 S values from − 42.1‰ to − 10.2‰ with the majority ranging from − 26‰ to − 14‰. Stage 2 mineralization has higher δ 34 S values (− 8.3‰–7.7‰). Combined with the geological settings and mineral paragenesis, the sulfur isotopic data presented here suggest multiple sulfur sources (biogenic sulfur + evaporites) and formation mechanisms for reduced sulfur (H 2 S). H 2 S responsible for stage 1 sulfide precipitation was associated with bacterial sulfate reduction (BSR). However, H 2 S of stage 2 was likely derived from thermochemical sulfate reduction (TSR). The most reasonable scenario for the stage 1 mineralization is a metal-bearing brine mixing with an H 2 S-rich fluid, thereby causing rapid sulfide precipitation. Till the stage 2, the ore-forming fluid shifted to the meteoric water that infiltrated and reacted with evaporitic rocks, leached metals and transported them as sulfate- or sulfite-complexes to the Jinding dome where the oxidized sulfur was reduced by organic matters to H 2 S, leading to precipitation of metal sulfides. In contrast to other sulfide deposits in the Lanping basin, biogenic sulfur might have played a key role in the mineralization process, especially during the early stage of formation of the Jinding Zn–Pb deposit.

Based on the experimental optimal designing method, the experimental plan was set up. In order to study anti-fatigue capability of the gear, the laser engraving technology was applied to process the grid type bionic micro-morphology texture on the gear teeth surface. Different anti-fatigue characteristics of the bionic samples were obtained through analyzing the fatigue tests results. The results showed that the pitting ratio of the gear specimens with the grid micro-morphology had been decreased obviously. The grid bionic surface micro-morphology on the gear had improved the anti-fatigue capability of the gear to 139%, and mechanism of anti-fatigue of the bionic gear was ascribed to “Dam Effect”, laser strengthen and changing of lubrication.

We aimed to explore the role of SIRT1 in apoptosis in human kidney proximal tubule epithelial (HK-2) cells, and to determine whether resveratrol (RSV, a SIRT1 activator) could ameliorate apoptosis in rats with streptozotocin-induced diabetes mellitus (DM) and/or in high glucose (HG, 30mM) - stimulated HK-2 cells. Rats were distributed randomly into three groups: 1) control group, 2) DM group, and 3) DM with RSV group (DM+RSV; rats treated with 30mg/kg/d of RSV for 16 weeks). The physical, biochemical, and morphological parameters were then examined. Additionally, the deacetylase activity of SIRT1, and the expression levels of SIRT1 and of representative apoptosis markers, such as p53, acetylated p53, cleaved caspase-3, caspase-9, and cleaved PARP, were measured. HK-2 cells were stimulated by HG for different lengths of time to study the effect of HG on apoptosis. HK-2 cells were treated with or without RSV (25μM) to investigate if RSV has a protective effect on HG-induced apoptosis. A gene-specific small interfering RNA against SIRT1 was used to study the role of SIRT1 in apoptosis. More apoptosis was found in the DM rats than in the control rats. Similarly, the expression levels of cleaved caspase-3, cleaved PARP, and acetylated p53 were significantly higher, and the level of SIRT1 was significantly lower, in the HK-2 cells that were cultured under HG conditions than those in the HK-2 cells that were cultured under low glucose (5.5mM) conditions. Notably, treatment with RSV lessened the HG-induced changes in the levels of apoptosis indicators, and this inhibition of HG-induced apoptosis in HK-2 cells by RSV treatment was abolished by SIRT1 silencing. Our study showed that hyperglycemia contributes to apoptosis in rat kidney and HK-2 cells. SIRT1 activation by RSV can reduce urinary albumin excretion and proximal tubule epithelial apoptosis both in vitro and in vivo. Based on our study, SIRT1/p53 axis played an important role in the hyperglycemia induced apoptosis. These findings indicated that the increased expression of SIRT1, mediated by RSV, is a possible mechanism by which RSV prevents renal tubular injury in diabetic nephropathy (DN). So RSV has great clinical significance and could provide the basis for the new way to effective treatment to contain the morbidity and mortality associated with DN.

With development of solar technology, high absorbance is no longer a hard problem in solar heat utilization. Many solar absorbing coating can easily get absorbance over 90%, but the coating materials and their manufacturing processes may harm seriously to human and environment. A typical plateau butterfly-- Lycaenidae was studied with bionic method in this work. It has considerable solar absorbing capacity for the physical microstructure in its wing scales but not chemicals. The 3D microstructure of the wing scales was measured and analyzed with SEM (Scanning Electronic Microscope) and TEM (Transition Electronic Microscope). The solar absorbing mechanism of the ridge and bottom microstructure was analyzed respectively based on geometrical optics and photon crystal theories. This study may promote solar heat utilization through a bionic structural material way.

Let X,{wj}j=1m,{pj}j=1m(2⩽m

The Xihuashan tungsten deposit in the central Nanling region, South China, is an important vein-type ore deposit hosted in Cambrian strata and Mesozoic granitic intrusions. Wolframite and molybdenite are the principal ore minerals. The gangue minerals are mainly quartz and muscovite. Wolframite and molybdenite are products of the first stage hydrothermal activity, whereas muscovite formed dominantly at the second stage. Molybdenite Re–Os and muscovite 40Ar/39Ar dating have been carried out to investigate the age of mineralization. Re–Os isotopic dating for molybdenite associated with wolframite yield a precise, well-constrained isochron age of 157.8 ± 0.9 Ma (MSWD = 1.5). Ar–Ar isotopic analyses of muscovite yield a plateau age of 152.8 ± 1.6 Ma, in agreement with an inverse isochron age of 152.8 ± 1.6 Ma, which is ~ 5 mys younger than the Re–Os age. The molybdenite Re–Os age is interpreted as the age of tungsten mineralization. This age coincides well with the zircon U–Pb age of the host granitic intrusion reported previously. The ~ 5 mys difference between molybdenite Re–Os and muscovite 40Ar/39Ar ages probably represents the duration of hydrothermal activity. The results show that the Xihuashan tungsten deposit is one of many important tungsten–tin deposits formed during 150 to 160 Ma associated with large-scale lithospheric extension in South China.

More than 90% of the tungsten resources of China are in the Nanling region of South China, and the Yaogangxian vein deposit is the largest tungsten deposit in this region. The tungsten deposits have ages of 150–160 Ma, and are spatially, temporally and genetically related to granites which were previously believed to be produced by crustal anatexis. This paper provides He and Ar isotope data of fluid inclusions in pyrite and arsenopyrite from the Yaogangxian W veins. 3He/4He ratios range from 0.41 to 3.03 Ra (where Ra is the 3He/4He ratio of air = 1.39 × 10−6), and 40Ar/36Ar ratios from 328 to 1,191. Moreover, there are excellent correlations between He and Ar isotopic compositions. The results suggest that the ore-forming fluids are a mixture between a crustal fluid containing atmospheric Ar and crustal 4He and a fluid containing mantle components. It is likely that the former is a low temperature meteoric fluid, and the later is a fluid exsolved from the W-associated granitic magma, which formed by crustal melting induced by intrusion of a mantle-derived magma.

Clubroot disease caused by Plasmodiophora brassicae is one of the most damaging diseases within the Brassicaceae family. To find landmarks for specific clubroot development stages, expression of several P. brassicae genes was analyzed during the infection process in a universally susceptible Brassica rapa line (cv. Granaat, ECD 05). The results revealed that the genes Pb -YPT, Pb -Brip9 and Pb -PSA were regulated during infection of P. Brassicae, Pb -Brip9 and Pb -PSA were expressed in early stages of infection. This study provides evidence that semi-quantitative RT-PCR could be used for discriminating developmental stages of P. brassicae in B. rapa . Stage-specific gene expression of P. brassicae should be studied in B. rapa roots due to longer disease development in comparison to Arabidopsis thaliana.

Planetary gear train (PGT) with herringbone gears is one of typical transmission styles used in marine power transmission. How to effectively design a PGT with lighter structures and lower vibration and noise is a fatal task for heavily loaded marine gearing. An analysis system which was developed in the past decades is introduced in this paper to simulate the performance of planetary herringbone gear trains. The effects of main crucial parameters on the static and dynamic characteristics of planetary herringbone gear trains are studied by using the analysis system. The results are discussed and show that the presented system is effective and can be used in design of planetary herringbone gear trains.

The common definition of vibration influence chart is proposed in this study. A 46 degree-of-freedom time-varying dynamic model with coupled translation-rotation effect is developed to simulate the vibration of an encased differential planetary gear system using lumped mass method. With the dynamic load and the acceleration on gears and bearings as references, the dynamic responses in different load cases are investigated to search the change law of concerned parameters. The parameters considered include mesh stiffness, structure stiffness, gear mass and moment of inertia. The good and poor regions for vibration are evidently presented in figures, which is convenient to conduct the parameters design of planetary gear systems.

The Shizhuyuan ore deposit in southern Hunan Province is a world-class W–Sn–Bi–Mo occurrence hosted by Devonian limestone in the thermal aureole of the Qianlishan granite. Mineralization coincided with intrusion of the granite pluton during Mesozoic crustal extension in South China. We present new He and Ar isotope data for volatiles released from pyrite in the Shizhuyuan deposit. Concentrations of 40Ar range from 0.21 to 2.38 × 10−6 cm3 STP 40Ar/g, and 4He concentrations range from 0.8 to 65.1 × 10−6 cm3 STP 4He/g. 3He/4He ratios vary from 0.06 to 1.66 Ra (where Ra is the 3He/4He ratio of air = 1.39 × 10−6) and 40Ar/36Ar ratios range from 293 to 1072. The isotopic compositions of He and Ar indicate that the ore-forming fluids were mantle-derived, modified by air-saturated crustal fluids. Shallow-level boiling increased 3He concentrations, whereas crustal contamination decreased 3He/4He ratios in the magmatic fluids. The occurrence of mantle-derived components in the magmatic fluid indicates that the asso...

To identify patients with highly elevated serum CA-125 levels and analyze their clinical characteristics.Patients with non-malignant gynecologic disease (NMGDs, n = 41), in whom serum CA-125 levels were over 1,000 IU/ml were retrospectively enrolled in the study. Seventy-one patients with epithelial ovarian cancer (EOC), in whom, serum CA-125 levels were over 1,000 IU/ml were included as the comparison group. Clinical parameters were compared between the two groups.In NMGDs group, 43.90% of the patients had endometriosis. The median of serum CA-125 level in NMGDs was much lower than that of EOC subjects (P0.001). Compared to EOC group, the patients in NMGDs group were much younger (P0.001) and had fewer histories of pelvic masses (P0.001) but had more clinical complaints such as acute abdominal symptoms (P0.001) and/or abnormal vaginal bleeding (P = 0.022). Clinical progresses of these two groups were correlated with changes of serum CA-125 levels by follow-up for up to 386 days.High levels of serum CA-125 were found not only in the EOC, but also in some NMGDs, especially in the reproductive patients with complaints of acute abdomen symptoms or abnormal vaginal bleeding.

The butterfly Apatura ilia is a species in the Northeast of China. There are billions of tiny scales on its wings, which overlap like roof tiles and completely cover the membrane, appearing as dust to people naked eye. The scales produce brilliant structural colour through their multilayer microstructure. In this paper, the microstructure and geometrical dimension of the scales were observed using a Scanning Electron Microscope (SEM). The cross section micro-configuration of the purple scales was achieved using a Transmission Electron Microscope (TEM). The reflectivity of the wing was measured by a spectrometer. The 3D multilayer microstructure of the ridges was optimized to 1D photonic crystal structure. The spectrometer experimental graph is in accord with the 1D photonic crystal simulation curves basically. In the end, the phenomenon of the purple structural colour was explained through the Snell equation.

There are billions of tiny scales on the butterfly wings, which array regularly as the tiles on the roof. Such tilts can form various colors of the wing and afford the species many abilities to survive and propagate. Morphological experiments on the wing scales of six butterfly species living in northeast of China were conducted. By the optics microscope, the form, geometry dimension and array of the scales were observed generally. By using scanning electron microscope (SEM), the 2D scanning and measurement were carried out and the surface micro configurations of scales were observed. The dimension and microstructure characteristics of the cross section of single scale were achieved through transmission electron microscope (TEM). Finally, by using 3D software, three 3D models were described and the 3D visual effect was achieved. This work can put forward a basic method for the future study on the morphology of biological microstructure.

In this paper, topology optimization of gearbox to reduce the radiated noise is studied based on the analysis of modal acoustic contribution and panel acoustic contribution. Firstly, the bearing dynamic loads are obtained by solving the dynamic equations of gear system. Secondly, the vibration of gearbox is calculated using FEM and the radiated noise is simulated using BEM by taking these bearing dynamic loads as excitations. Thirdly, the panel having larger contribution to the sound pressure level (SPL) at a specific field point is found by panel acoustic contribution analysis (PACA), and this panel is taken as design domain. The mode order with larger contribution is determined by modal acoustic contribution analysis (MACA), and making corresponding natural frequency becomes far away from excited frequency is taken as a constraint. Finally, the topology optimization of gearbox is completed using SIMP method, and the ribs are arranged according to the optimization results. The results show that the equivalent sound pressure level at objective field point can be reduced obviously by using this method.Copyright © 2015 by ASME

In the advanced manufacturing technology, how to integrate CAD/CAE software has become a very important research issue. After analyzing the function framework of collaborative design and simulation platform, the management model of collaborative design and simulation platform for numerical engineering is proposed in this paper. Moreover, workflow management technology, collaborative running management, collaborative development model database, database management, and Win32 API message interception technology are studied in detail. An object-oriented software integration method is presented. The method is divided into three lays: interface integration, data integration, and operation integration. A C/S structural prototyping system is developed by using C# and XML under .NET development environment. The system can support customizing engineering design and simulation task, which integrates various design and simulation tools, including some self-developed application tools.

This work investigates the influences of manufacturing errors on the vibration of a helical gear pair under different load conditions. A combined finite element and analytical contact model is built to efficiently predict the mesh stiffness and loaded transmission error for gears with arbitrary tooth surface deviations. The proposed equivalent meshing error and mesh stiffness are both introduced as exciting forces to transform the time variant dynamic equations into time-invariant ones. It is found that the actual mesh stiffness will be altered and larger dynamic factors will be brought under light load conditions due to the manufacturing errors.

Idiopathic pulmonary fibrosis (IPF) is a fatal lung disease characterized by expansion of the fibroblast and myofibroblast population and extracellular matrix deposition. Although the pathogenic mechanisms of IPF remain to be fully elucidated, there is emerging evidence that fibroblasts and myofibroblasts may be derived partially from alveolar epithelial cells by epithelial‑mesenchymal transition (EMT). In the present study, A549 cells were treated with different concentrations of Wnt1 and the results indicated that the mRNA and protein expression levels of vimentin, α‑smooth muscle actin (α‑SMA) and collagen Ⅰ gradully increased and those of E‑cadherin gradully decreased in a concentration‑dependent manner. Furthermore, the A549 cells were transfected with β‑catenin plasmid cells, revealing phenotypic changes in the cells from a pebble to a fusiform shape. The mRNA and protein expression levels of of vimentin, α‑SMA and collagen Ⅰ increased significantly, whereas those of E‑cadherin decreased significantly. The present study examined the roles of alveolar epithelial cell injury and profibrogenic cytokine release in EMT and their association with the Wnt/β‑catenin signaling pathway in a mouse model of bleomycin‑induced pulmonary fibrosis. Bronchoalveolar fluid was obtained 7 days after treatment with bleomycin and the A549 cells were incubated for 48 h. An increase in the expression levels of the mesenchymal markers, α‑SMA, vimentin and collagen Ⅰ, and a concomitant decrease in the expression of the epithelial marker, E‑cadherin were observed. This corresponded with an increased expression of β‑catenin. When the A549 cells were infected with a lentivirus expressing β‑catenin shRNA, no significant increase was observed in the expression of the mesenchymal cell markers and the expression of E‑cadherin did not decrease. These findings demonstrated that activation of the Wnt signaling pathway was capable of inducing an EMT program in the lung epithelial cells through β‑catenin and that injured alveolar epithelium activated the Wnt/β‑catenin signaling pathway, thereby inducing the expansion of the fibroblast/myofibroblast population through EMT. These results suggested that β‑catenin was involved in the formation of lung fibrosis and may provide a theoretical basis for the treatment of IPF.

Idiopathic pulmonary fibrosis (IPF) is a fibrotic lung disease associated with a high rate of mortality, characterised by an accumulation of fibroblasts/myofibroblasts in the fibroblastic foci (FF) and by an excessive deposition of extracellular matrix (ECM) in the lung parenchyma. The pathogenesis of this fatal disorder remains unclear. Previous evidence suggests that myofibroblasts are key effectors of the deposition of ECM. In the present study, human embryonic pulmonary fibroblast (HEPF) cells were incubated with different concentrations of Wnt1. The present study revealed that cell proliferation improved following stimulation using different concentrations of Wnt1 in a concentration-dependent manner. When the concentration exceeded 20 µg/l, cell proliferation was significant (P