Modulation of replication of simian virus 40 by oncogene proteins.

Modulation of replication of simian virus 40 by oncogene proteins

Analysis of Polycyclic Aromatic Hydrocarbons in Ambient Aerosols by Using One-Dimensional and Comprehensive Two-Dimensional Gas Chromatography Combined with Mass Spectrometric Method: A Comparative Study

Advanced separation technology paired with mass spectrometry is an ideal method for the analysis of atmospheric samples having complex chemical compositions. Due to the huge variety of both natural and anthropogenic sources of organic compounds, simultaneous quantification and identification of organic compounds in aerosol samples represents a demanding analytical challenge. In this regard, comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (GC×GC-TOFMS) has become an effective analytical method. However, verification and validation approaches to quantify these analytes have not been critically evaluated. We compared the performance of gas chromatography with quadrupole mass spectrometry (GC-qMS) and GC×GC-TOFMS for quantitative analysis of eighteen target polycyclic aromatic hydrocarbons (PAHs). The quantitative obtained results such as limits of detection (LODs), limits of quantification (LOQs), and recoveries of target PAHs were approximately equivalent based on both analytical methods. Furthermore, a larger number of analytes were consistently identified from the aerosol samples by GC×GC-TOFMS compared to GC-qMS. Our findings suggest that GC×GC-TOFMS would be widely applicable to the atmospheric and related sciences with simultaneous target and nontarget analysis in a single run

Trace Level Determination of Saccharides in Pristine Marine Aerosols by Gas Chromatography—Tandem Mass Spectrometry

The quantification and identification of saccharides in pristine marine aerosols can provide useful information for determining the contributions of anthropogenic and natural sources of the aerosol. However, individual saccharide compounds in pristine marine aerosols that exist in trace amounts are difficult to analyze due to their low concentrations. Thus, in this study, we applied gas chromatography–tandem mass spectrometry (GC-MS/MS) in multiple reaction monitoring (MRM) mode to analyze the particulate matter with an aerodynamic diameter equal or less than 2.5 μm (PM2.5) samples, and the results were compared with those of conventional GC-MS. To investigate the chemical properties of pristine marine aerosols, 12 PM2.5 samples were collected while aboard Araon, an ice-breaking research vessel (IBRV), as it sailed from Incheon, South Korea to Antarctica. The method detection limits of GC-MS/MS for 10 saccharides were 2–22-fold lower than those of GC-MS. Consequently, the advantages of GC-MS/MS include (1) more distinct peak separations, enabling the accurate identification of the target saccharides and (2) the quantification of all individual saccharide compounds with concentrations outside the quantifiable range of GC-MS. Accordingly, the time resolution for sampling saccharides in pristine marine aerosols can be improved with GC-MS/MS

Activation of T cell response to allogeneic DCs stimulated with dLOS.

<p>BMDCs from C57BL/6 mice were stimulated with dLOS (•) or MPL (○) at various concentrations for 24 h and co-cultured for 5 days with naïve CD4-positive T cells isolated from BALB/c mice. Culture supernatants were harvested and analyzed for IFN-γ, IL-5, and IL-17 produced by activated T cells. Data are expressed as mean ± SD of values obtained from triplicate reactions and represent two similar experiments.</p

Increased expression of cell surface co-stimulatory molecules and cytokines in mouse BMDCs.

<p>(A) Mouse BMDCs were cultured for 24 h in the presence of LPS, MPL, or dLOS, and expression of CD40, CD80, or CD86 on CD11c-positive populations was assessed by flow cytometry (□). Unstimulated splenocytes are shown for comparison (▪). (B) Mean fluorescence intensity (MFI) for each molecule is shown as histograms. (C) Culture supernatants were assessed for TNF-α, IL-6, and IL-12 levels by sandwich ELISA. Values are the mean ± SD of triplicate cultures. ^** and ^***, <i>P</i><0.01 and <i>P</i><0.001 as compared with MPL-treated cells, respectively. Data represent two independent experiments with similar results.</p

TLR4-dependence of dLOS activity on mouse BMDC maturation.

<p>BMDCs isolated from <i>TLR4^+/+</i> and <i>TLR4^−/−</i> BALB/c mice were stimulated for 24 h with LPS, MPL, dLOS, or medium alone. Expression of CD40, CD80, or CD86 on CD11c- positive populations was assessed by flow cytometry. CpG oligonucleotide (10 µg/ml) was used as a positive control.</p

Serum cytokine profiles.

<p>BALB/c mice (<i>n</i> = 3) were given an intramuscular injection with LPS (1 µg), MPL (1 or 5 µg), or dLOS (1 or 5 µg) alone or in combination with alum at a ratio of 1∶50. Control and alum groups were given saline and 250 µg alum, respectively. Blood was collected 1 h or 4 h after the injection and individual serum samples were assessed for cytokine levels using multiplex cytokine assays. Data are expressed as mean ± SD of values obtained from three mice. Statistical significance between experimental groups; ^*, <i>P</i><0.05; ^**, <i>P</i><0.01; ^***, <i>P</i><0.001. Statistical difference between LPS- and MPL-treated groups is not shown in the figure.</p