Memories of studying life in Emory University

<p>Gestational-age specific risks^{<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0155692#t004fn001" target="_blank">*</a>} of adverse perinatal outcomes comparing cesarean-section (130,808 infants) vs. vaginal (n = 232,812 infants) deliveries in twin pregnancies.</p

Researching peers and disaster vulnerable communities: an insider perspective

Conducting research among peers and communities that a researcher also serves may be both daunting and rewarding. Researching peers may make the researcher feel uncomfortable raising certain questions that are sensitive or that could be construed to be testing their competencies. This paper is inclined more towards showing that it is advantageous to be an insider, whose position can facilitate collection of information that could not have been accessed, or revealed to an outsider. The paper reports on fieldwork conducted in a low-income country in Sub-Sahara Africa as part of a doctoral study with communities affected by disasters and those that work with such communities. The paper demonstrates the complexities of conducting such research and provides some insights that may be useful to insiders, outsiders or “in-betweeners” embarking on fieldwork in low-income countries and among vulnerable population struggling with manifold stresses and shocks

Association of XPC Polymorphisms and Lung Cancer Risk: A Meta-Analysis

<div><p>Background</p><p>Xeroderma pigmentosum complementation group C gene (XPC) is a key member of nucleotide excision repair pathway and plays an important role in human DNA repair system. It is reported that several common polymorphisms of XPC are associated with susceptibility to lung cancer. However, the conclusion is still elusive.</p><p>Method</p><p>This meta-analysis was performed to determine the relationship between XPC polymorphisms (Lys939Gln, Ala499Val, and PAT) and lung cancer risk. Published literatures were identified by searching online databases and reference lists of relevant studies. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to estimate the association strength. Publication bias were detected by Egger’s and Begg’s test.</p><p>Result</p><p>After strict screening, we identified 14 eligible studies in this meta-analysis, including 5647 lung cancer cases and 6908 controls. By pooling all eligible studies, we found that the homozygote Gln939Gln genotype was associated with a significantly increased risk of lung cancer in Asian population (GlnGln vs LysLys, OR = 1.229, 95% CI: 1.000–1.510; GlnGln vs LysLys/LysGln, OR = 1.257, 95% CI: 1.038–1.522). As for the PAT polymorphism, in Caucasian population, we found carriers of the −/− genotype were associated significantly reduced risk of lung cancer in homozygote comparison model (−/− vs +/+, OR = 0.735, 95% CI: 0.567–0.952).</p><p>Conclusion</p><p>In this meta-analysis we found that Gln939Gln genotype was associated with significantly increased risk of lung cancer in Asian population; the PAT −/− genotype significantly reduced susceptibility to lung cancer in Caucasian population; while the XPC Ala499Val polymorphism was not associated with lung cancer risk.</p></div

Forrest plot of XPC Lys939Gln polymorphism (GlnGln vs. LysLys/LysGln) by ethnicity.

<p>Forrest plot of XPC Lys939Gln polymorphism (GlnGln vs. LysLys/LysGln) by ethnicity.</p

Forrest plot of XPC PAT polymorphism (−/− vs. +/+) by ethnicity.

<p>Forrest plot of XPC PAT polymorphism (−/− vs. +/+) by ethnicity.</p

Baseline Characteristics of Eligible Studies.

a<p>the two populations were treated as two separate studies; b: disagreement of HWE for Lys939Gln polymorphism; HB: hospital-based studies; CB: community-based studies.</p

Meta-analysis results of XPC Lys939Gln polymorphism.

<p>OR: odds ratio; CI: confidence intervals; *significant association.</p

Flow Diagram of study selection.

<p>*the two populations in Chang JS’s study were treated as 2 separate studies.</p

Meta-Analysis Results of XPC PAT Polymorphism.

<p>OR: odds ratio; CI: confidence intervals; NA: not available; *significant association.</p

Simultaneous Quantification of Antioxidant Compounds in <i>Phellinus igniarius</i> Using Ultra Performance Liquid Chromatography-Photodiode Array Detection-Electrospray Ionization Tandem Mass Spectrometry

<div><p>Natural antioxidants are widely used in the life sciences. <i>Phellinus igniarius</i> is a historically used natural antioxidant containing a variety of active compounds. Phenols, particularly Inoscavin A and Hypholomine B, are found in the high concentrations. Better quantitative methods are needed to perform quality control in order to support further research of this mushroom. An ultra-performance liquid chromatography method coupled to photodiode-array detection and an electrospray ionization tandem mass spectrometry method (UPLC-PAD-MS) was developed to simultaneously quantify Inoscavin A and Hypholomine B levels in the medicinal fungus <i>Phellinus igniarius</i>. The two compounds were quantified using UPLC-PAD and UPLC-MS. The methods were accurate (mean accuracy for spiked matrix ranged from 101.5% to 105.8%), sensitive (limit of detection ranged from 0.28 to 1.14 mg L^-1) and precise (the relative standard deviations ranged from 0.13 to 2.8%). Inoscavin A and Hypholomine B were purified using high-speed counter-current chromatography (HSCCC), structural evaluated to meet the request of standard substances. UPLC separation was performed on a reversed-phase C18 column using gradient elution with acetonitrile and 0.1% formic acid over 10 min. The developed method was successfully applied to determine Inoscavin A and Hypholomine B in twelve <i>Phellinus igniarius</i> samples of different origins and the results showed that it was suitable for the analysis of these active components in <i>Phellinus igniarius</i> samples.</p></div