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We investigated the effects of mitochondrial damage via carbon ion irradiation on the proliferation of human non-small cell lung cancer (A549) cells by monitoring mitochondrial morphological changes, mitochondrial membrane potential transformation, release of membrane-associated proteins, and mitophagy. A549 cell proliferation and activity were monitored by CCK-8 and colony formation assays. Changes in mitochondrial morphology and mitochondrial membrane potential were detected by mitochondrial membrane-specific fluorescence staining. Expression of associated proteins was detected by western blot and real-time quantitative PCR. Annexin V-FITC and PI staining were used to detect cell apoptosis. Mitophagy was detected by immunofluorescence co-localization and western blot. The apoptosis rate of mitochondria-lacking A549 cells after carbon ion irradiation was also quantitated. Irradiation with carbon ions at dose of 4 Gy significantly depressed the proliferation capacity of A549 cells, and induced mitochondrial shrinkage and decreased mitochondrial membrane potential. Levels of mitochondrial membrane protein Bax/Bak, and intermembrane proteins Cyto-C and SMAC were elevated, with increased apoptosis and mitophagy. In cells depleted of mitochondria, carbon ion irradiation exerted no significant effect on A549 cell apoptosis. Carbon ion irradiation can inhibit A549 cell proliferation. The half maximal inhibitory exposure dose is 4 Gy. Carbon ions lose their anti-proliferative function in mitochondria-free A549 cells. In summary, carbon ion irradiation can decrease mitochondrial membrane potential and induce the release of pro-apoptotic proteins, thereby inhibiting A549 cell proliferation.

The aim of this study was to investigate the effects of ionizing radiation (IR) on ciliogenesis of human glioblastoma cells. The glioblastoma cell lines M059K and M059J were exposed to X-ray or carbon ion at different doses, and the incidence and length of primary cilia that emerged were detected by immunofluorescence. A colony formation assay was used to investigate the influence of primary cilia interference by siRNA against IFT88 (siIFT88) on the cellular sensitivity to IR. The results showed that both M059K and M059J harbor primary cilia, with the incidence in M059K and M059J cells at (41.36±4.75)% and (8.07±1.58)%, respectively. The average length of cilia in both cells exceeded 3 μm, with M059J cells having lower frequency and shorter length of primary cilia, and exhibiting a prominently higher radiosensitivity compared to M059K cells. Conversely, X-ray irradiation significantly increased the incidence of primary cilia in M059K cells, and the rate of ciliogenesis reaching approximately 60% when exposed to 10 Gy. Notably, suppression of ciliogenesis by siIFT88 remarkably elevated the radiosensitivity of M059K cells. Moreover, IR-induced ciliogenesis showed dose-dependent and time-response characteristics. In summary, IR promotes ciliogenesis by increasing both number and length of primary cilia, and the obstruction of primary ciliogenesis enhances the radiosensitivity of glioblastoma cells.

In this paper, Leray-Schauder nonlinear alternative theorem is used to study the existence of positive solutions for nth-order integral boundary value problems with p-Laplacian operator on infinite interval {(φp(x(n-1)))' (t) + a(t) f(t,x(t),x'(t)) = 0, 0 < t < + ∞, x(0) = α∫η+∞ g (τ)x(τ)dτ,x'(0) = x"(0) = ⋯ = xn-2 (0) = 0, … x(n-1) (t) = 0 where η ∈ [0, + ∞), α ∈ [0, + ∞) and f ∈ C([0, + ∞) X R X R, [0, + ∞)). [ABSTRACT FROM AUTHOR]

In this paper, the quadrature method is used to study the existence of multiple positive solutions for second-order three-point boundary value problems with one-dimensional p-Laplacian operator ... where p ∈ (1,2], 0 < η < 1 is a constant, λ ∈ (0, + ∞) is a parameter, f ∈ C¹ ([0, r), [0, r), [0, + ∞)) for some constant r > 0, f (s) > 0 in (0, r) and ... (r-s)p-1 f (s) = +∞. [ABSTRACT FROM AUTHOR]

In this paper, the sensor fault accommodation problem for the attitude control system of near space vehicle in reentry flight phase is investigated by using the generalized augmented system method. Firstly, the T-S fuzzy model is represented by the nonlinear attitude control system of near space vehicle in reentry phase. Meanwhile, the sensor fault model is introduced. Secondly, the T-S fuzzy model with sensor fault for near space vehicle is transformed into a T-S fuzzy singular system by using the generalized augmented system. A full-dimension state observer which is used to estimate the state vectors and the sensor fault vectors of the attitude control system is designed. Based on the estimated fault, the feedback control scheme is given by utilizing sensor fault compensation technique, such that the closed-loop control system can asymptotic accommodate the effect of sensor fault. Finally, simulation results are given to demonstrate the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

The article discusses the popularity in the United States of the cable news network Fox News Channel, as a manifestation of the political conservatism of American society. The network's brief history is recounted, from its founding in 1996 to its move in just over five years to surpass competitor CNN (Cable News Network) in viewer popularity, and its continuing success. The station's style is discussed, and seen as secondary to the conservative slant of its content as a reason for its rapid growth.

Objective To investigate the effect of CDKN2A/p16 INK4a , a cyclin-dependent kinase inhibitor, on cell morphology and cytoskeleton in MCF7 breast cancer cells by tetracycline operon (Tet-on) inducible gene expression system. Methods MCF7 cells, genetically null for p16 INK4a expression, were sequentially infected with two viruses of Tet-on systems to make MCF7-pTet-on-p16 INK4a cells, which were induced to express p16NK4a by doxycycline (Dox) treatment. Cell growth was evaluated by cell counting. To observe the effect of p16 INK4a on cell adhesion and cytoskeleton, intercellular adhesion and intracellular F-actin were examined by fluorescent staining with anti-E-cadherin antibody and phalloidin, respectively. Changes in cell morphology were analyzed by ImageJ software after microscopic imaging. Results Cell line expressing p16 INK4a upon Dox induction was successfully made in MCF7 breast cancer cells. The inducible expression of p16 INK4a inhibited cell proliferation while significantly increasing cell size as marked by prolonged contour lines. Furthermore, intracellular F-actin were enriched at the cortical peripheries of p16 INK4a -expressing cells, which was different from those in control MCF7 cells where F-actin were enriched in cytoplasmic regions. Conclusion p16 INK4a expression in MCF7 breast cancer cells leads to increased cell size, weakened intercellular adhesion and cortical re-distribution of cytoskeletal F-actin.

We cloned genes of four sentrin-specific protease (SENP), three small ubiquitin-like modifiers (SUMO), enhanced cyan fluorescent protein (ECFP) and yellow fluorescent protein (EYFP) by two-step PCR. Then we constructed expression vector B28 for SENP and B13 for ECFP-SUMO-EYFP. The recombinant plasmids were transformed into Escherichia coli BL21 and expression was induced by isopropyl beta-D-thiogalactoside, then recombinant proteins were purified by Ni-NTA agarose column ion-exchange chromatography. The proteins were analyzed with SDS-PAGE and identified with Western blotting. Except that SENP3 catalytic domain (SENP3C) truncated in the C termini and SENP5C expressed in inclusion body, others were expressed as soluble proteins. SDS-PAGE analysis showed that the relative molecular mass of these fusion proteins were consistent with theoretical ones, and the specificity of the fusion proteins were confirmed with Western blotting. The fusion proteins of SENP and ECFP-SUMO-EYFP can be successfully expressed in prokaryotic expression system. It lays the foundation for the fluorescence resonance energy transfer analysis.

Monoclonal antibodies (McAbs) against human liver DnaJ-like protein (HLJ1) was produced by using lymphocyte-hybridoma technique and then one method for the detection of HLJ1 antigen was established. Two hybridoma cell lines which stably secreted monoclonal antibodies against HLJ1 were generated and named for A4C7 and C4C8. Subtypes of the two McAbs were both IgG1, and the antibodies showed high titer and good specificity. Using the prepared monoclonal antibody, human embryonic liver tissues were examined by immunohistochemistry. The results indicated that HLJ1 located in the cytoplasm of the human embryonic liver cell. A double antibodies sandwich ELISA was established by using C4C8 and HRP labeled A4C7. This assay had good specificity, and the lowest detection limit was 7.5 ng/mL and the linear range was 7.5-750 ng/mL. In conclusion, an immunohistochemistry method and a sensitive sandwich ELISA were established for the detection of HLJ1 protein.

The finding of endothelium derived relaxing factor (EDRF) and the illumination of its chemical identity, bio-synthesis and physiological functions promoted greatly the research on vascular disease. The EDRF was verified as NO or R-O-NO by many experimental results, and several pathological processes such as hypertension, atherosclerosis and heart failure were considered to be associated with abnormalities of endothellium-dependent vascular relaxation and decrease of basal EDRF and/or storage EDRF. As the provider of EDRF, Nitryl vascular relaxation substance could remedy EDRF and might play an important role in clinical therapy and prevention of human vascular disease.