Dual Role of Multiroom-Structured Sn-Doped NiO Microspheres for Ultrasensitive and Highly Selective Detection of Xylene

Sn-doped NiO multiroom spheres with unique microreactor morphology were prepared by facile ultrasonic spray pyrolysis of a solution containing tin oxalate, nickel nitrate, and dextrin and subsequent heat treatment. The multiroom structure was formed by phase segregation between the molten metal source and liquidlike dextrin and sequent decomposition of dextrin during spray pyrolysis, which played the dual roles of enhancing gas response and selectivity. The response (resistance ratio) of the Sn-doped NiO multiroom spheres to 1 ppm <i>p</i>-xylene was as high as 65.4 at 300 °C, which was 50.3 and 9.0 times higher than those of pure NiO multiroom spheres and Sn-doped NiO dense spheres, respectively. In addition, the Sn-doped NiO multiroom sensors showed a high selectivity to xylene. The unprecedented high response that enables the sensing of sub-ppm xylene was explained by the high gas accessibility of the multiroom structures and the Sn-doping-induced change in oxygen adsorption as well as the charge carrier concentration, whereas the high xylene selectivity was attributed to the decomposition/re-forming of xylene into smaller or more active species within the unique multiroom structure of Sn-doped NiO microreactors characterized by high catalytic activities. The multiroom oxide spheres can be used as a new and generalized platform to design high-performance gas sensors

7α-Hydroxycholesterol induces monocyte/macrophage cell expression of interleukin-8 via C5a receptor

<div><p>We investigated effects of 7-oxygenated cholesterol derivatives present in atherosclerotic lesions, 7α-hydroxycholesterol (7αOHChol), 7β-hydroxycholesterol (7βOHChol), and 7-ketocholesterol (7K), on IL-8 expression. Transcript levels of IL-8 and secretion of its corresponding gene product by monocytes/macrophages were enhanced by treatment with 7αOHChol and, to a lesser extent, 7K, but not by 7βOHChol. The 7-oxygenated cholesterol derivatives, however, did not change transcription of the IL-8 gene in vascular smooth muscle cells. 7αOHChol-induced IL-8 gene transcription was inhibited by cycloheximide and Akt1 downregulation, but not by OxPAPC. Expression of C5a receptor was upregulated after stimulation with 7αOHChol, but not with 7K and 7βOHChol, and a specific antagonist of C5a receptor inhibited 7αOHChol-induced IL-8 gene expression in a dose dependent manner. Pharmacological inhibitors of PI3K and MEK almost completely inhibited expression of both IL-8 and cell-surface C5a receptor induced by 7αOHChol. These results indicate that 7-oxygenated cholesterol derivatives have differential effects on monocyte/macrophage expression of IL-8 and C5a receptor and that C5a receptor is involved in 7αOHChol-induced IL-8 expression via PI3K and MEK.</p></div

Effects of inhibition of PI3K/Akt1 and MEK on 7αOHChol-induced IL-8 expression.

<p>(A) THP-1 cells were treated with 7αOHChol for 48 h in the absence or presence of LY294002 or U0126 (10 μM each). Transcript levels of IL-8 were assessed by realtime-PCR. Data are expressed as the means ± SD (n = 3 replicates for each group). *** P < 0.001 vs. control; ## P < 0.01 vs. 7αOHChol; ### P < 0.001 vs. 7αOHChol. (B) THP-1 cells were infected with lentiviruses expressing Akt1 shRNA or control lentiviruses. After selection in the presence of puromycin, expression of Akt1 transcripts was examined by RT-PCR. (C) THP-1 cells infected with lentiviruses expressing Akt1 shRNA or control lentiviruses were stimulated for 48 h with or without 7αOHChol. Transcript levels of IL-8 were assessed by realtime-PCR. Data are expressed as mean ± SD (n = 3 replicates/group). * P < 0.05; ** P < 0.01; *** P < 0.001.</p

Roles of C5a receptor in on 7αOHChol-induced IL-8 expression.

<p>(A) THP-1 cells were incubated with or without 7-oxygenated cholesterol derivatives (5 μg/ml each) for 48 h. Transcripts of C5a receptor were amplified by RT-PCR. (B) THP-1 cells were incubated with or without 7-oxygenated cholesterol derivatives for 48 h, and surface expression of C5a receptor was analyzed by flow cytometry. (C) THP-1 cells were pre-treated for 2 h with the indicated amount of W-54011 and stimulated with 7αOHChol (5 μg/ml) for 48 h. Transcript levels of IL-8 were assessed by real-time PCR. Data are expressed as mean±SD (n = 3 replicates for each group). ***P < 0.001 vs. control. ### P < 0.001 vs. 7αOHChol.</p

Effects of 7αOHChol on expression of IL-8.

<p>(A) THP-1 cells were incubated with 7αOHChol (5 μg/ml) for the indicated time periods. The levels of IL-8 transcripts were assessed by real-time PCR. Data are expressed as the means ± SD (n = 3 replicates for each group). * P < 0.05 vs. 0 h; *** P < 0.001 vs. 0 h. (B) THP-1 cells were incubated in the presence of the indicated amounts of 7αOHChol for 48 h. The levels of IL-8 transcripts were assessed by real-time PCR. Data are expressed as the means ± SD (n = 3 replicates for each group). *** P < 0.001 vs. 0 μg/ml. (C) THP-1 cells were treated for 48 h with 7αOHChol (5 μg/ml) and 27OHChol (2.5 μg/ml). The levels of IL-8 transcripts were assessed by realtime-PCR. Data are expressed as the means ± SD (n = 3 replicates for each group). *** P < 0.001 vs. control. (D) THP-1 cells were incubated for 48 h with or without 7αOHChol (5 μg/ml) in the absence or presence of CHX (1 μg/ml). Transcripts of IL-8 were amplified by RT-PCR (upper panel), and the levels of IL-8 transcripts were determined by real-time PCR (lower panel). Data are expressed as the means ± SD (n = 3 replicates for each group). *** P < 0.001 vs. control; ### P < 0.001 vs. 7αOHChol.</p

Effects of 7-oxygenated cholesterol derivatives on expression of the IL-8 gene.

<p>(A) THP-1 cells and human aortic smooth muscle cells (HAoSMCs) were incubated with or without the indicated 7-oxygenated cholesterol derivatives (5 μg/ml each) for 48 h. Transcripts of IL-8 were amplified by RT-PCR. (B) THP-1 cells serum-starved for 24 h in RPMI 1640 containing 0.1% BSA (endotoxin free) were incubated with or without 7-oxygenated cholesterol derivatives for 48 h, and the levels of IL-8 transcripts were assessed by real-time PCR. The y-axis values represent fold increases of IL-8 mRNA levels normalized to GAPDH levels relative to those of THP-1 cells incubated carrier of oxygenated cholesterol derivatives (control). Data are expressed as the means ± SD (n = 3 replicates for each group). **P < 0.01 vs. control; ***P < 0.001 vs. control. (C) Conditioned media were harvested after treatment of THP-1 cells (2 x10⁵ cells/ml) with or without 7-oxygenated cholesterol derivatives (5 μg/ml each) for 48 h. The amount of CXCL8 secreted into the media was measured by ELISA. Data are expressed as the means ± SD (n = 3 replicates for each group). *P < 0.05 vs. control; *** P < 0.001 vs. control.</p

Effects of inhibitors of PI3K and MEK on expression of C5a receptor.

<p>THP-1 cells were treated with 7αOHChol for 48 h in the absence or presence of LY294002 or U0126 (10 μM each). The surface expression of C5a receptor was determined by flow cytometry.</p

Optimized detection of insertions/deletions (INDELs) in whole-exome sequencing data

<div><p>Insertion and deletion (INDEL) mutations, the most common type of structural variance, are associated with several human diseases. The detection of INDELs through next-generation sequencing (NGS) is becoming more common due to the decrease in costs, the increase in efficiency, and sensitivity improvements demonstrated by the various sequencing platforms and analytical tools. However, there are still many errors associated with INDEL variant calling, and distinguishing INDELs from errors in NGS remains challenging. To evaluate INDEL calling from whole-exome sequencing (WES) data, we performed Sanger sequencing for all INDELs called from the several calling algorithm. We compared the performance of the four algorithms (<i>i</i>.<i>e</i>. GATK, SAMtools, Dindel, and Freebayes) for INDEL detection from the same sample. We examined the sensitivity and PPV of GATK (90.2 and 89.5%, respectively), SAMtools (75.3 and 94.4%, respectively), Dindel (90.1 and 88.6%, respectively), and Freebayes (80.1 and 94.4%, respectively). GATK had the highest sensitivity. Furthermore, we identified INDELs with high PPV (4 algorithms intersection: 98.7%, 3 algorithms intersection: 97.6%, and GATK and SAMtools intersection INDELs: 97.6%). We presented two key sources of difficulties in accurate INDEL detection: 1) the presence of repeat, and 2) heterozygous INDELs. Herein we could suggest the accessible algorithms that selectively reduce error rates and thereby facilitate INDEL detection. Our study may also serve as a basis for understanding the accuracy and completeness of INDEL detection.</p></div

Comparison of INDEL-calling algorithms.

<p>Comparison of INDEL-calling algorithms.</p

Sources of INDEL detection error from WES.

<p>(A) Number of validated INDELs in the following INDEL size. (B) Percentages of homozygous, heterozygous, repeat, and non-repeat in the validated and not validated set. (C) PPVs of error sources, 1) heterozygous, 2) repeat INDELs in all and GATK & SAMtools intersecting call set.</p