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Lung cancer is the most common malignancy worldwide. This study aimed to identify miRNA biomarkers of lung adenocarcinoma and to investigate their molecular mechanisms. miRNA expression profiling of tumor tissues and adjacent normal tissues from 10 patients were detected using microarray. Differentially expressed miRNAs (DEMs) were identified, and were verified using quantitative reverse transcription-PCR. Thereafter, correlations between DEM expression and clinicopathological features were determined in 49 patients. Furthermore, Targetscan was utilized to predict target genes, among which transcription factors (TFs) were identified. The interactions among miRNAs, TFs and target genes were used to construct an miRNA-TF-target network. Totally, 11 DEMs were identified, among which two downregulated miRNAs (miR-126-3p and miR-451a) were validated. Low levels of miR-126-3p and miR-451a were associated with poor pathological stage, large tumor diameter and lymph node metastasis (P0.05). Receiver operating characteristic analysis showed that both miRNAs could predict pathological stage, tumor diameter and lymph node metastasis of lung adenocarcinoma (AUC0.65, P0.05). For miR-126-3p, 154 target genes were predicted (e.g., PLXNB2), which were enriched in 29 pathways mainly concerning apoptosis and cancer. For miR‑451a, 397 target genes were predicted, which were enriched in 5 pathways including 'PPAR signaling pathway'. Ten genes were co-regulated by miR-126-3p and miR-451a, e.g., TSC1. Furthermore, an miRNA-TF-target network was constructed, and a sub-network was identified, including 2 miRNAs, 15 targets, and 7 TFs. In conclusion, miR-126-3p and miR-451a predicted the severity of lung adenocarcinoma. However, the possible mechanisms explored by bioinformatics need to be further validated.

The present study reports the case of a 77-year-old female that was asymptomatic at presentation and was found to possess a lesion that was incidentally identified on a computed tomography (CT) scan. The CT scan revealed a non-homogeneous, hypodense, non-lobulated solid mass, ~1.2 cm in diameter, in the left upper lobe of the lung that demonstrated minimal contrast enhancement. The following CT scan was performed only two years later. This scan revealed that the non-homogeneous round mass had increased in size to ~1.7 cm in diameter, and possessed an irregular margin, in addition to being slightly lobulated with no calcification or fat. Combined positron emission tomography and CT revealed a lobulated mass that was ~1.9 cm in diameter, demonstrating an irregular margin with involvement of the mediastinal pleura. Slight uptake of 18F-fluorodeoxyglucose was also detected. The final histological diagnosis was pulmonary hamartoma.

Maleated poly(propylene carbonate) (PPC-MA)/organo-montmorillonite (OMMT) nanocomposites were first prepared via melt end-capping poly(propylene carbonate) (PPC) with maleic anhydride (MA) and melt-mixing the PPC-MA with commercial OMMT without and with hydroxyl groups in surfactants: Cloisite 20A (C20A) and Cloisite 30B (C30B), respectively. Intercalated and partially delaminated morphologies were corroborated via X-ray diffraction (XRD) and transmission electron microscopy (TEM). Dynamic mechanical analysis (DMA) revealed that PPC-MA was evidently reinforced by the partially delaminated C30B platelets. From XRD patterns of statically annealed PPC-MA/C20A and PPC-MA/C30B mixtures and Fourier transform infrared (FTIR) results of equivalent nanocomposites, partial delamination of C30B in PPC-MA was confirmed to be relevant to diffusion of PPC-MA molecular chains in C30B galleries, grafting of PPC-MA to C30B platelet surfaces and further separation of C30B platelets.

The miscibility and the isothermal crystallization kinetics for PBT/Epoxy blends have been studied by using differential scanning calorimetry, and several kinetic analyses have been used to describe the crystallization process. The Avrami exponents n were obtained for PBT/Epoxy blends. An addition of small amount of epoxy resin (3%) leads to an increase in the number of effective nuclei, thus resulting in an increase in crystallization rate and a stronger trend of instantaneous three-dimensional growth. For isothermal crystallization, crystallization parameter analysis showed that epoxy particles could act as effective nucleating agents, accelerating the crystallization of PBT component in the PBT/Epoxy blends. The Lauritzen-Hoffman equation for DSC isothermal crystallization data revealed that PBT/Epoxy 97/3 had lower nucleation constant K, than 100/0, 93/7, and 90/10 PBT/Epoxy blends. Analysis of the crystallization data of PBT/Epoxy blends showed that crystallization occurs in regime II. The fold surface free energy, sigma(e) = 101.7-58.0 x 10(-3) J/m(2), and work of chain folding, q = 5.79-3.30 kcal/mol, were determined. The equilibrium melting point depressions of PBT/Epoxy blends were observed and the Flory-Huggins interaction parameters were obtained.

A series of novel AB3-type monomers were prepared from nontoxic natural gallic acid and amino acids. These monomers were then melt-polycondensed in the presence of MgO as a catalyst via a transesterification process at 170-190 degrees C to yield the hyperbranched poly(ester-amide)s bearing terminal acetyl groups. FTIR and NMR spectra confirmed the structures of all the monomers and polymers. The degrees of branching, estimated from 1H NMR and quantitative 13C NMR spectra, were 0.50-0.68. These hyperbranched polymers displayed moderately high molecular weights. Hydrolytic and enzymatic degradation studies were carried out in vitro at 37.5 degrees C in NaOH hydrotropic solution and in Tris-HCl buffer (pH = 8.6) containing proteinase K, respectively. The results indicate that the hyperbranched poly(ester-amide)s are degradable hydrolytically as well as enzymatically, and the rate of hydrolytic degradation increases with the pH value of the solution.

Wide-angle X-ray diffraction (WAXD) was used to investigate the crystal transition of nylon-12,12 under annealing and drawing. The triclinic α-form could be obtained by crystallizing from a melted state or by annealing the γ-form at high temperature (above 150°C). The crystal structure of the α-form annealed at 90 °C didn't change with time except for the perfection of crystals and an increase in the degree of crystallinity. The pseudo-hexagonal γ-form could be produced by crystallizing from the melted state at low temperature (90 °C) or by drawing at 90 and 160 °C. This is the first time a Brill transition has been observed under drawing conditions, instead of under the traditional conditions of continuous heating and cooling. Experimental results also confirm that drawing inducement is preferable to produce the γ-form and plays an important role in determining the crystal structure; there is a competition between drawing inducement and thermal inducement.

The crystallization kinetics of biodegradable poly(butylene succinate-co-adipate) (PBS/A) copolyester was investigated by using differential scanning calorimetry (DSC) and polarized optical microscopy (POM), respectively. The Avrami and Ozawa equations were used to analyze the isothermal and nonisothermal crystallization kinetics, respectively. By using wide-angle X-ray diffraction (WAXD), PBS/A was identified to have the same crystal structure with that of PBS. The spherulitic growth rates of PBS/A measured in isothermal conditions are very well comparable with those measured by nonisothermal procedures (cooling rates ranged from 0.5 to 15 C/min). The kinetic data were examined with the Hoffman-Lauritzen nucleation theory. The observed spherulites of PBS/A with different shapes and textures strongly depend on the crystallization temperatures.

The crystallization behavior of nylon 1212, irradiated at 60Co γ-rays (50 kGy), was studied by a rheometer, polarized optical microscopy (POM), and differential scanning calorimeter (DSC). The results showed that irradiated nylon 1212 samples exhibited abnormal crystallization behavior during the crystallization process: The Avrami exponent n was calculated and was found to be in the range from 2.06–2.41 for isothermal crystallization, and from 2.67–4.91 for nonisothermal crystallization; the spherulite morphology also changed largely by polarized optical microscopy (POM); the crystallization activation energy ΔE for isothermal and nonisothermal crystallization process of irradiated nylon 1212 are determined to be 57.4 kJ/mol and 78.65 kJ/mol, respectively, which are lower than that of nonirradiated nylon 1212. At the same time, a new method by a combination of the Avrami and Ozawa equations was successfully applied to analyze the noncrystallization process of irradiated nylon 1212. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 2326–2333, 2005

Differential scanning calorimetry was used to investigate the isothermal crystallization, subsequent melting behavior, and nonisothermal crystallization of syndiotactic 1,2-polybutadiene (st-1,2-PB) produced with an iron-based catalyst system. The isothermal crystallization of two fractions was analyzed according to the Avrami equation. The morphology of the crystallite was observed with polarized optical microscopy. Double melting peaks were observed for the samples isothermally crystallized at 125-155 °C. The low-temperature melting peak, which appeared approximately 5 °C above the crystallization temperature, was attributed to the melting of imperfect crystals formed by the less stereoregular fraction. The high-temperature melting peak was associated with the melting of perfect crystals formed by the stereoregular fraction. With the Hoffman-Weeks approach, the value of the equilibrium melting temperature was derived. During the nonisothermal crystallization, the Ozawa method was limited in obtaining the kinetic parameters of st-1,2-PB. A new method that combined the Ozawa method and the Avrami method was employed to analyze the nonisothermal crystallization of st-1,2-PB. The activation energies of crystallization under nonisothermal conditions were calculated.

The isothermal and nonisothermal crystallization kinetics of partially melted nylon-1212 was investigated with differential scanning calorimetry. Because of partial melting, the pre-existing crystals changed the crystallization mechanism and had a strong effect on the crystallization process. The Avrami exponent and interfacial free energy of the chain-folded surface of partially melted nylon-1212 were higher than those of completely melted nylon-1212. The work of chain folding was determined to be 5.9 kcal/mol. The activation energy of the isothermal crystallization process was determined to be 399.1 kJ/mol, far higher than that of complete melting. The crystallization rate coefficient and Jeziorny analysis indicated that the ability of nonisothermal crystallization for partially melted nylon-1212 was enhanced. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 3222–3230, 2005

The isothermal and non-isothermal melt-crystallization kinetics of nylon 1212 were investigated by differential scanning calorimetry. Primary and secondary crystallization behaviors were analysed based on different approaches. The results obtained suggested that primary crystallization under isothermal conditions involves three-dimensional spherulite growth initiated by athermal nucleation, while under non-isothermal conditions, the mechanism of primary crystallization is more complex. Secondary crystallization displays a lower-dimensional crystal growth, both in the isothermal and non-isothermal processes. The crystallite morphology of nylon 1212, isothermally crystallized at various temperatures, was observed by polarized optical microscopy. The activation energies of crystallization under isothermal and non-isothermal conditions were also calculated based on different approaches.

The isothermal and non-isothermal crystallization processes of nylon 1212 were investigated by polarized optical microscopy. The crystal growth rates of nylon 1212 measured in isothermal conditions at temperatures ranged from 182 to 132 degreesC are well comparable with those measured by non-isothermal procedures (cooling rates ranged from 0.5 to 11 degreesC/min). The kinetic data were examined with the Hoffman-Lauritzen nucleation theory on the basis of the obtained values of the thermodynamic parameters of nylon 1212. The classical regime I --> II and regime II --> III transitions occur at the temperatures of 179 and 159 degreesC, respectively. The crystal growth parameters were calculated with (100) plane assumed to be the growth plane. The regime I --> II --> III transition is accompanied by a morphological transition from elliptical-shaped structure to banded spherulite and then non-banded spherulite. The development of morphology during isothermal and non-isothermal processes shows a good agreement.

In this paper, the structures and properties of the neutral and doped blends of poly(3-dodecylthiophene) (P3DDT) with low-density polyethylene (LDPE) were investigated. Wide-angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC), Fourier transform infrared spectra (FTIR), and scanning electron microscopy (SEM) were used to characterize the structures and morphologies of the blends, and conductivity was also measured. It was found that separate crystallizations occur between P3DDT and LDPE. When the amount of P3DDT is small in the blend, it has the effect of a nucleation reagent and has some influence on the crystal structure. After doping, the interaction force between the molecular chains increases, and leads to a more compact packing and a more uniform dispersion in morphology. Through blending, the thermal stability of pure component could be greatly improved, especially when the P3DDT content is 5 wt %. The conductivity measurements indicate that the conductivity increases with the increase of the P3DDT composition and doping time.

BACKGROUND: Atrial fibrillation (AF) is one of the most common types of arrhythmia in humans. Recently, many studies have investigated the relationship between human atrial fibrillation and the single nucleotide polymorphism (SNP) of rs1805127 (A>G) in KCNE1 gene, but the results were still inconsistent and inconclusive. METHOD: Electronic databases and bibliographies of retrieved studies were searched. We performed a meta-analysis of ten case-control studies, including 2099 cases and 2252 controls, to evaluate the association of rs1805127 polymorphism (A>G) with the risk of AF. Random-effects model was used when the heterogeneity was obvious; otherwise, fixed-effects model was applied. Meta-regression was performed to examine potential source of heterogeneity. Egger's test and Begg's test were used to detect publication biases. RESULTS: The results showed a significantly increased risk of AF in homozygote comparison (GG vs. AA:OR = 1.899, 95%CI: 1.568, 2.300; Pheterogeneity = 0.217), heterozygote comparison (GA vs. AA:OR = 1.436, 95% CI:1.190, 1.732; Pheterogeneity = 0.739), dominant model(GA /GG vs. AA: OR = 1.624, 95%CI: 1.361, 1.938; Pheterogeneity = 0.778) and recessive model (GG vs. GA/AA: OR = 1.394, 95%CI:1.152, 1.686; Pheterogeneity = 0.03). Meta-regression revealed that the sample size and the types of AF were the source of the heterogeneity. CONCLUSION: The rs1805127 polymorphism (A>G) of KCNE1 is associated with an increased risk of AF, which suggests the rs1805217 polymorphism of KCNE1 gene may play an important role in the pathogenesis of AF.

Curcumin, a natural and crystalline compound isolated from the plant Curcuma longa with low toxicity in normal cells, has been shown to protect against carcinogenesis and prevent tumor development. However, little is known about antimetastasis effects and mechanism of curcumin in lung cancer. Rac1 is an important small Rho GTPases family protein and has been widely implicated in cytoskeleton rearrangements and cancer cell migration, invasion and metastasis. In this study, we examined the influence of curcumin on in vitro invasiveness of human lung cancer cells and the expressions of Rac1. The results indicate that curcumin at 10 μM slightly reduced the proliferation of 801D lung cancer cells but showed an obvious inhibitory effect on epidermal growth factor or transforming growth factor β1-induced lung cancer cell migration and invasion. Meanwhile, we demonstrated that the suppression of invasiveness correlated with inhibition of Rac1/PAK1 signaling pathways and matrix metalloproteinase (MMP) 2 and 9 protein expression by combining curcumin treatment with the methods of Rac1 gene silence and overexpression in lung cancer cells. Laser confocal microscope also showed that Rac1-regulated actin cytoskeleton rearrangement may be involved in anti-invasion effect of curcumin on lung cancer cell. At last, through xenograft experiments, we confirmed the connection between Rac1 and the growth and metastasis inhibitory effect of curcumin in vivo. In summary, these data demonstrated that low-toxic levels of curcumin could efficiently inhibit migration and invasion of lung cancer cells through inhibition of Rac1/PAK1 signaling pathway and MMP-2 and MMP-9 expression, which provided a novel insight into the molecular mechanism of curcumin against lung cancer.

To investigate the association between transporter associated with antigen processing 1 (TAP1) rs1057141 and rs1135216 gene polymorphisms and predisposition to allergic rhinitis (AR) in Xinjiang Han people.A case control study was conducted. The region of the TAP1 * rs1057141 and rs1135216 was studied in 150 Xinjiang Han people with allergic rhinitis and 150 normal controls by using SNaPshot system, and these data were compared with other ethics groups in the world according to the NCBI gene bank.The genotypes distribution of the group were in the Hardy-Weinberg equilibrium(P0.05). The frequencies of three genotypes(G/G, G/A, A/A) of TAP1 * rs1057141 were 4.00%, 30.00%, 66.00% in controls and 2.70%, 33.30%, 64.00% in AR groups , which showed no difference (P0.05). The frequencies of three genotypes (G/G,G/A,A/A) of TAP1 * rs1135216 were 2.0%, 28.7%, 69.3% in controls and 1.30%, 27.30%, 71.40% in AR groups, which showed no difference either (P0.05). According to the NCBI database, there was difference between Xinjiang Han people and other ethnics in the world.Lacking association was found between the mutation of TAP1 * rs1057141, rs1135216 gene G allele and allergic rhinitis in the Xinjiang Han people. Maybe TAP1 * rs1057141, rs1135216 were not susceptibility genes to AR. And apparent differences existed in TAP1 gene polymorphisms between Xinjiang Han people and other ethnic groups in the world.

Pulmonary sclerosing hemangioma (PSH) is a relatively rare benign neoplasm, often asymptomatic and presenting as a solitary pulmonary nodule on radiological imaging studies. In the present case report, we examined a case of PSH in a young adult female, and reviewed the literature pertaining to PSH with an emphasis on (18)F-fluorodeoxyglucose positron emission tomography/computed tomography ((18)FDG PET/CT) and pathology. Immunohistochemical staining was also performed to confirm the diagnosis of sclerosing hemangioma. The results revealed that the tumor cells were immunopositive for epithelial membrane antigen, thyroid transcription factor-1 and vimentin and cytoskeleton 7. The patient recovered and was discharged. Thus, (18)FDG PET/CT may be used in the diagnosis of a solitary benign pulmonary nodule.

In this paper, a novel three-dimensional (3D) microelectrode integrated with micro and nano architectures has been developed to enhance the property of amperometric microsensor. By silicon bulk micromachining technology, a 3D micrometer-scale pyramidal micropool array (PMA) has been fabricated on working electrode surface. The PMA redistributes electric field strength over working electrode surface. The disequilibrium of electric field makes more porous metallic nanoparticles (NPs) clusters with large effective surface electrodeposited at micropool fringe, where the electric field is stronger. The proposed PMA can be applied for many metallic NPs to improve the microelectrode surface modification. Plantium nanoparticles (PtNPs) have been modified on PMA in this work. The results demonstrate that, the effective surface of PtNPs/PMA microelectrode is enlarged by about 40-fold than that of the planar microelectrode (PME). Compared with PtNPs-modified PME, PtNPs/PMA microelectrode has higher response current and 6-fold sensitivity for hydrogen peroxide (H 2 O 2 ).

To investigate the expression feature of Cx43 protein in non-small cell lung cancer and its clinical significance.Paraffin embedded tissues from 65 patients with primary non-small cell lung cancer and 20 adjacent non-cancerous lung tissues were investigated for expression of Cx43 protein by immunohistochemistry (ABC method). The relationship between Cx43 protein expression and clinicopathological characteristics of lung cancer was analyzed.Cx43 protein was positively expressed in 24 out of 65 lung cancer tissues (36.92%), and in all 20 adjacent non-cancerous lung tissues. There was a significant difference in Cx43 expression between stage I-II and stage III-IV groups ( P0.05), as well as between moderate-well and poor differentiation groups ( P0.01). Primary lung cancer tissues with lymph node metastasis showed lower expression of Cx43 than those without lymph node metastasis ( P0.01). The positive rate of Cx43 expression was not related to histological classification ( P0.05).Cx43 expression might play a role in the genesis, development and metastasis of lung cancer. It may be used to judge the biological behavior of lung cancer.

Several studies have shown that curcumin can induce apoptosis and inhibit growth in human A549 lung adenocarcinoma cells. However, the mechanism is not completely understood yet. The present study was designed to investigate the effects of curcumin on A549 cells to better understand its apoptosis and apoptosis-related factors in vitro. The apoptosis induction, intracellular reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) were examined by confocal fluorescence microscope and flow cytometry. The MAPK protein expression was examined by Western blot analysis. After treatment with curcumin, apoptosis were observed. Curcumin-induced apoptosis was accompanied by an increase of intracellular ROS level and a loss of MMP. In addition, induction of apoptosis was also accompanied by sustained phosphorylation and activation of JNK, p38 and ERK. However, pretreatment with MAPK inhibitors had no effect upon curcumin-induced apoptosis. GSH and NAC, an anti-oxidant agent, blocked the curcumin-induced ROS production, MMP loss and rescued cells from curcumin-induced apoptosis. Our results indicated that curcumin induced apoptosis in A549 cells through a reactive oxygen species-dependent mitochondrial signaling pathway and independent of MAPK signaling pathway.

Several studies have shown that curcumin can induce apoptosis and inhibit growth in human A549 lung adenocarcinoma cells. However, the mechanism is not completely understood yet. In the present study, we investigated the in vitro effect of curcumin on cell viability, apoptosis and disorganization of the actin cytoskeleton in A549 cells. Our results showed that curcumin significantly inhibited the viability of A549 cells in a dose- and time-dependent manner by induced apoptosis. The apoptotic process was associated with a disorganization of the architecture of actin microfilaments and a decrease in the levels of F-actin. DMSO-treated control cells exhibited a well-defined F-actin network that was mainly organized into stress fibers. The actin fibers in cells treated with curcumin or the positive control drug cytochalasin B were disorganized, disassembled, or disrupted, however, the disorganization of actin fibers and apoptosis could be prevented by phalloidin, an F-actin stabilizing compound. Thus, these results demonstrated that actin filament disorganization might play a central role in the curcumin-induced apoptosis of A549 cells.

A combination of extrinsic hematopoietic growth regulators, such as stem cell factor (SCF), interleukin (IL)-3 and IL-6, can induce division of quiescent hematopoietic stem cells (HSCs), but it usually impairs HSCs' self-renewal ability. However, intrinsic negative cell cycle regulators, such as p18INK4C (p18), p27Kip1 (p27) and MAD1, can regulate the self-renewal of HSCs. It is unknown whether the removal of some extrinsic regulators and the knockdown of intrinsic negative cell cycle regulators via RNA interference (RNAi) induce ex vivo expansion of the HSCs. To address this question, a lentiviral vector-based RNAi tool was developed to produce two copies of small RNA that target multiple genes to knockdown the intrinsic negative cell cycle regulators p18, p27 and MAD1. Colony-forming cells, long-term culture-initiating cells (LTC-IC) and engraftment assays were used to evaluate the effects of extrinsic and intrinsic regulators. Results showed that the medium with only SCF, but without IL-3 and IL-6, could maintain the sca-1+c-kit+ bone marrow cells with high LTC-IC frequency and low cell division. However, when the sca-1+c-kit+ bone marrow cells were cultured in a medium with only SCF and simultaneously knocked down the expression of p18, p27 and MAD1 via the lentiviral vector-based RNAi, the cells exhibited both high LTC-IC frequency and high cell division, though engraftment failed. Thus, the simultaneous knockdown of p18, p27 and MAD1 with a medium of only SCF can induce LTC-IC expansion despite the loss of engraftment ability.

In this paper, melt blends of poly(propylene carbonate) (PPC) with poly(butylene succinate) (PBS) were characterized by dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC), tensile testing, wide-angle X-ray diffraction (WAXD), polarized optical microscopy and thermogravimetric analysis (TGA). The results indicated that the glass transition temperature of PPC in the 90/10 PPC/PBS blend was decreased by about 11 K comparing with that of pure PPC. The presence of 10% PBS was partially miscible with PPC. The 90/10 PPC/PBS blend had better impact and tensile strength than those of the other PPC/PBS blends. The glass transition temperature of PPC in the 80/20, 70/30, and 60/40 PPC/PBS blends was improved by about 4.9 K, 4.2 K, and 13 K comparing with that of pure PPC, respectively; which indicated the immiscibility between PPC and PBS. The DSC results indicated that the crystallization of PBS became more difficult when the PPC content increased. The matrix of PPC hindered the crystallization process of PBS. While the content of PBS was above 20%, significant crystallization-induced phase separation was observed by polarized optical microscopy. It was found from the WAXD analysis that the crystal structure of PBS did not change, and the degree of crystallinity increased with increasing PBS content in the PPC/PBS blends.