Toll-like receptor (TLR)-4 mediates anti-β2GPI/β2GPI-induced tissue factor expression in THP-1 cells

Our previous study demonstrated that annexin A2 (ANX2) on cell surface could function as a mediator and stimulate tissue factor (TF) expression of monocytes by anti-β₂-glycoprotein I/β₂-glycoprotein I complex (anti-β₂GPI/β₂GPI). However, ANX2 is not a transmembrane protein and lacks the intracellular signal transduction pathway. Growing evidence suggests that Toll-like receptor 4 (TLR-4) might act as an 'adaptor' for intracellular signal transduction in anti-β₂GPI/β₂GPI-induced TF expressing cells. In the current study, we investigated the roles of TLR-4 and its related molecules, myeloid differentiation protein 2 (MD-2) and myeloid differentiation factor 88 (MyD88), in anti-β₂GPI/β₂GPI-induced TF expressing human monocytic-derived THP-1 (human acute monocytic leukaemia) cells. The relationship of TLR-4 and ANX2 in this process was also explored. Along with TF, expression of TLR-4, MD-2 and MyD88 in THP-1 cells increased significantly when treated by anti-β₂GPI (10 µg/ml)/β₂GPI (100 µg/ml) complex. The addition of paclitaxel, which competes with the MD-2 ligand, could inhibit the effects of anti-β₂GPI/β₂GPI on TLR-4, MD-2, MyD88 and TF expression. Both ANX2 and TLR-4 in THP-1 cell lysates could bind to β₂GPI that had been conjugated to a column (β₂GPI-Affi-Gel). Furthermore, TLR-4, MD-2, MyD88 and TF expression was remarkably diminished in THP-1 cells infected with ANX2-specific RNA interference (RNAi) lentivirus (LV-RNAi-ANX2), in spite of treatment with a similar concentration of anti-β₂GPI/β₂GPI complex. These results indicate that TLR-4 and its signal transduction pathway contribute to anti-β₂GPI/β₂GPI-induced TF expression in THP-1 cells, and the effects of TLR-4 with ANX2 are tightly co-operative.

Comparative serum proteomic analysis of patients with acute-on-chronic liver failure: alpha-1-acid glycoprotein maybe a candidate marker for prognosis of hepatitis B virus infection

The acute-on-chronic liver failure (AoCLF) caused by hepatitis B virus (HBV) infection remains to be a challenge in clinics with a high mortality rate in China, and it is important to identify biomarkers to foresee the prognosis of patients with HBV. The current study analysed serum proteome changes of acute-on-chronic liver failure as a result of acute exacerbation of chronic hepatitis B infection. Serum samples were collected from normal subjects (NS, n = 8), patients with chronic hepatitis B (CHB, n = 12) and patients with AoCLF (n = 12). After removal of albumin/IgG and ultramembrane centrifugation, serum proteins were separated by two-dimensional gel electrophoresis. Differentially expressed spots were identified by matrix-associated laser desorption ionization time-of-flight tandem mass spectrometry. Through the removal of albumin/IgG and ultramembrane centrifugation, the well-resolved and reproducible two-dimensional gel electrophoresis (2-DE) profiles were obtained. A total of 23 proteins were identified on 2-DE profiles by their differential expression between the three cohorts. Mass spectrometry analysis resulted in the identification of 12 proteins unambiguously. Western blot analysis confirmed the proteomics results that the α1-acid glycoprotein (α1-AGP) levels decrease significantly in plasma of patients with AoCLF, but somewhat decreased in patients with chronic HBV. Further α1-AGP levels in bulk serum samples were measured by immune turbidimetry including normal subjects group (n = 25), acute hepatitis group (n = 36), chronic hepatitis group (n = 52) and AoCLF group (n = 48), the level of α1-AGP in AoCLF groups sharply decrease than other groups. Our study shows that α1-AGP may be a potential plasma biomarker for AoCLF diagnosis because of acute exacerbation of chronic hepatitis B infection.

Temperature and density effects on the absorption maximum of solvated electrons in sub- and super-critical methanol

The optical absorption spectra of the solvated electron ([Formula: see text]) in sub- and super-critical methanol are measured by both electron pulse radiolysis and laser photolysis techniques, at temperatures in the range 220–270 °C. Over the density range studied (~0.45–0.59 g/cm3), the position of the absorption maximum ([Formula: see text]) of [Formula: see text] is found to shift only slightly to the red with decreasing density. In agreement with our previous work in water, at a fixed pressure, [Formula: see text] decreases monotonically with increasing temperature in passing through the phase transition at Tc (239.5 °C). By contrast, at a fixed density, [Formula: see text] exhibits a minimum as the solvent passes above the critical point into the supercritical state. These behaviors are discussed in terms of microscopic arguments based on the changes that occur in the methanol properties and methanol structure in the sub- and super-critical regimes. The effect of the addition of a small amount of water to the alcohol on the optical absorption energy of [Formula: see text] is also investigated.

Diurnal variations in solar ultraviolet radiation on horizontal and vertical plane

BACKGROUND

In general, measurements of solar ultraviolet (UV) radiation are related to horizontal surfaces. While the humans walking and standing outdoors expose to the natural solar UV radiation, their eyes, cheeks, extremities, trunks, or many other anatomical sites are close to vertical plane and random orient to different directions. In this study, we characterized the diurnal variations in solar UV on horizontal and vertical plane which may be helpful to obtain more relevant information on UV exposure of humans.

METHODS

The UV exposure on vertical and horizontal plane were measured using Solar-UV Sensors in Shenyang (41°51″N, 123°27″E) and Sanya (18°19'N, 109°42'E), PR China.

RESULTS

As the well known, the diurnal variations in solar UV on horizontal plane in a sunny day exhibited unimodal distributions, reached a single UV peak exposure at around solar noon. However, the diurnal variations on vertical plane presented bimodal distributions, with two peaks in summer in Shenyang and Sanya, and a unimodal distribution in winter in Shenyang. In spring and autumn in Shenyang, the UV exposure around noon were slightly flat with no significant peaks but relative high. When the Solar Elevation Angle (SEA) is about 40°, the vertical plane may potentially receiving maximal unweighted total solar UV radiation exposures.

CONCLUSION

The results potentially showed that the protection of some vertical and near-vertical anatomical sites of human body from high UV exposure should not only focused on the periods of before and after noon especially in high SEA places.

Allergy and risk of glioma: a meta-analysis

We evaluated the association between allergic conditions and the risk of glioma in case-control and cohort studies published so far on this issue. A total of 12 studies (10 case-control and 2 cohort studies) were included in the analysis, involving 61 090 participants, of whom 6408 had glioma. When compared with non-allergic conditions, the pooled odds ratio (OR) with any allergic conditions for glioma was 0.60 (95% CI: 0.52-0.69, P<0.001), suggesting a significant negative association (protective effect) between allergy and glioma. Subgroup analysis showed that the ORs were 0.70 (95% CI: 0.62-0.79, P<0.001), 0.69 (95% CI: 0.62-0.78, P<0.001), and 0.78 (95% CI: 0.70-0.87, P<0.001) for asthma, eczema, and hay fever, respectively. The significant association remained even after excluding the bias of proxy reporting (OR=0.61; 95% CI: 0.50-0.75, P<0.001). We conclude that allergic conditions may significantly reduce the risk of glioma.

Differential profiles of gene expression in grouper Epinephelus coioides, infected with Singapore grouper iridovirus, revealed by suppression subtractive hybridization and DNA microarray

Suppression subtractive hybridization (SSH) was used to generate a subtracted cDNA library enriched with gene transcripts differentially expressed in the spleen of orange-spotted grouper Epinephelus coioides after 5 days of infection with Singapore grouper iridovirus (SGIV). In the forward and reverse-subtracted libraries, 260 and 153 non-redundant expressed sequence tags (EST), respectively, were identified. These annotated genes responding to SGIV infection were grouped into eight gene categories related to immunity, cell structure, transcription-translation, cell signalling, metabolism, mitochondrial proteins, ribosomal proteins and unknown or hypothetical proteins. A DNA microarray containing all the differentially expressed genes was constructed, and the gene expression patterns in different tissues were investigated in virus-infected E. coioides. Of these genes, four associated with the infection processes were identified and further investigated by quantitative real-time PCR. These results provide new insights into the molecular basis of host-pathogen interactions in E. coioides, and will help the development of control strategies against SGIV infection.

Protein phosphatase 2A has an essential role in the activation of gamma-irradiation-induced G2/M checkpoint response

G2/M checkpoint activation after DNA damage results in G2/M cell cycle arrest that allows time for DNA repair before the entry of cells into mitosis. Activation of G2/M checkpoint involves a series of signaling events, which include activation of ataxia telangiectecia-mutated and Rad3-related (ATR) and Chk1 kinases and inhibition of Cdc2/Cyclin B activity. Studies presented in this report show that serine (Ser)/threonine (Thr) protein phosphatase 2A (PP2A) has an important role in G2/M checkpoint activation in response to gamma-irradiation (IR) exposure. Using PP2A inhibitors, as well as siRNA targeting various forms of Ser/Thr protein phosphatases, results presented in this report show that specific PP2A inhibition abrogates IR-induced activation of ATR and Chk1 kinases, as well as phosphorylation of Cdc2-Tyr15, and attenuates IR-induced G2/M arrest. These results suggest an important regulation of PP2A on IR-induced G2/M checkpoint signaling response.

Electrochemical Instrumentation of a Hip Simulator: A New Tool for Assessing the Role of Corrosion in Metal-On-Metal Hip Joints

Polyethylene wear debris induced osteolysis has triggered investigations to find alternative material combinations to the well-established metal-on-polyethylene hip implants. Owing to some early successful clinical cases, metal-on-metal (MoM) hip replacements have been attracting more and more interest. There is, however, considerable concern about the propensity of MoM hip replacements to release metal ions and fine, nanometre-scale metallic wear debris. The long-term effect from released metal ions and wear particles is still not clear.

To date, all the work on hip simulators focused on assessing mass losses damage has been referred to as ‘wear’. However, it is known in the field of tribocorrosion that mechanical removal of the passive layer on Co—Cr alloys can significantly enhance corrosion activity. In total joint replacements, it is possible that corrosion plays a significant role. However, no one has ever tried to extract, on a hip simulator, what proportion of the damage is due to mechanical processes and the corrosion processes. This paper describes the first instrumentation of an integrated hip joint simulator to provide in-situ electrochemical measurements in real time. The open circuit potential results are reported to assess the corrosion regime in the absence and presence of movement at the bearing surfaces. The importance of these measurements is that the real damage mechanisms can be assessed as a function of the operating cycle.