Data_Sheet_1_Simultaneous Colorimetric Detection of a Variety of Salmonella spp. in Food and Environmental Samples by Optical Biosensing Using Oligonucleotide-Gold Nanoparticles.docx

Optical biosensors for rapid detection of significant foodborne pathogens are steadily gaining popularity due to its simplicity and sensitivity. While nanomaterials such as gold nanoparticles (AuNPs) are commonly used as signal amplifiers for optical biosensors, AuNPs can also be utilized as a robust biosensing platform. Many reported optical biosensors were designed for individual pathogen detection in a single assay and have high detection limit (DL). Salmonella spp. is one of the major causative agents of foodborne sickness, hospitalization and deaths. Unfortunately, there are around 2,000 serotypes of Salmonella worldwide, and rapid and simultaneous detection of multiple strains in a single assay is lacking. In this study, a comprehensive and highly sensitive simultaneous colorimetric detection of nineteen (19) environmental and outbreak Salmonella spp. strains was achieved by a novel optical biosensing platform using oligonucleotide-functionalized AuNPs. A pair of newly designed single stranded oligonucleotides (30-mer) was displayed onto the surface of AuNPs (13 nm) as detection probes to hybridize with a conserved genomic region (192-bases) of ttrRSBCA found on a broad range of Salmonella spp. strains. The sandwich hybridization (30 min, 55°C) resulted in a structural formation of highly stable oligonucleotide/AuNPs-DNA complexes which remained undisturbed even after subjecting to an increased salt concentration (2 M, final), thus allowing a direct discrimination via color change of target (red color) from non-target (purplish-blue color) reaction mixtures by direct observation using the naked eye. In food matrices (blueberries and chicken meat), nineteen different Salmonella spp. strains were concentrated using immunomagnetic separation and then simultaneously detected in a 96-well microplate by oligonucleotide-functionalized AuNPs after DNA preparation. Successful oligonucleotide/AuNPs-DNA hybridization was confirmed by gel electrophoresis while AuNPs aggregation in non-target and control reaction mixtures was verified by both spectrophotometric analysis and TEM images. Results showed that the optical AuNP biosensing platform can simultaneously screen nineteen (19) viable Salmonella spp. strains tested with 100% specificity and a superior detection limit of <10 CFU/mL or g for both pure culture and complex matrices setups. The highly sensitive colorimetric detection system can significantly improve the screening and detection of viable Salmonella spp. strains present in complex food and environmental matrices, therefore reducing the risks of contamination and incidence of foodborne diseases.</p

The relationship between serum iron and interleukin-6 levels in all subjects.

<p>(Dependent variable: serum iron concentration).</p><p>*<i>P</i><0.05 and **<i>P</i><0.001, general linear model. AMI, acute myocardial infarction; IL-6, interleukin 6; SE, standardized error. The intercept is the predicted value of serum iron concentration in AMI group. The predicted value is 71.872 µg/dl. The serum iron concentration in the control group was, on average, 35.494 µg/dl higher than that in the AMI group. For every one unit increase in IL-6 concentration, there was a decrease of 0.625 units in serum iron concentration.</p

Univariate correlation between serum iron concentration and patient characteristics after acute myocardial infarction.

<p>*<i>P</i><0.05, Spearman’s rho correlation.6 M, six months; TIMI, thrombolysis in myocardial infarction; EF 6 M, left ventricular ejection fraction at 6–month follow-up.</p

Characteristics of patients grouped by change in left ventricular ejection fraction 6 months after percutaneous coronary interventions for acute myocardial infarction.

<p>*<i>P</i><0.05, Mann–Whitney U test.</p><p>6 M, six months; BMI, body mass index; CPK, creatine- phosphor-kinase; CKMB, creatine phosphokinase-MB; HbA1C, glycohemoglobin; HDL-C, high density lipoprotein cholesterol; LDL-C, low density lipoprotein cholesterol; hsCRP, high sensitivity C reactive protein; IL-6, interleukin 6; WMSI, wall motion score index; TIMI, thrombolysis in myocardial infarction; LVMI, left ventricular mass index; LVEF, left ventricular ejection fraction; E/A ratio, the ratio of the peak velocities of early (E wave) and late (A wave) diastolic filling; DT, the deceleration time of the E wave; EDV, left ventricular end diastolic volume; ESV, left ventricular end systolic volume; Hb, hemoglobin; RDW, red blood cell distribution width; LAD, left anterior descending artery; RCA, right coronary artery; LCX, left circumflex artery; D2B, door to balloon; PCI, percutaneous coronary interventions; TIMI, thrombolysis in myocardial infarction.</p

The relationships between serum iron concentration and TIMI risk scores after primary angioplasty for AMI.

<p>The AMI patients were divided into four subgroups according to TIMI risk score for STEMI: Group 1 (TIMI risk score 1, n = 8); Group 2 (TIMI risk score 2, n = 15); Group 3 (TIMI risk score 3, n = 19); and Group 4 (TIMI risk score ≥4, n = 13). Trend analysis with Jonckheere-Terpstra test found that serum iron concentration significantly decreased as TIMI risk score rose (<i>P</i> = 0.002).</p

Lower serum iron concentration is associated with higher inflammatory markers and TIMI risk score after acute myocardial infarction.

<p>*<i>P</i><0.05, Mann–Whitney U test. TIMI, thrombolysis in myocardial infarction; IL-6, interleukin 6.</p

The relationship between serum iron concentration and IL-6 levels in all enrolled subjects.

<p>The result indicated that the serum iron concentration was negatively correlated with circulating IL-6 concentration in all study subjects. The linear relationship was well described by Serum iron = 95.994−1.246 (IL-6), R² = 0.133 and <i>P</i><0.001.</p

Trend analysis showed serum iron concentration was inversely proportional to IL-6 concentration in STEMI patients.

<p>AMI patients were divided into three subgroups according to circulating IL-6 concentration tertile: group 1, IL-6 concentration ≤10.48 pg/ml (n = 19); group 2, IL-6 concentration between 10.49–19.67 pg/ml (n = 20); group 3, IL-6 concentration ≥19.68 pg/ml (n = 16). Trend analysis showed serum iron concentration was inversely proportional to IL-6 concentration. (Jonckheere-Terpstra test, <i>P</i> = 0.043).</p

Multiple linear regression analysis of variables associated with ejection fraction 6 months after primary angioplasty for acute myocardial infarction.

<p>(Dependent variable: ejection fraction at 6 months).</p><p><i>R²</i> = 0.620.</p><p>*<i>P</i><0.05 and **<i>P</i><0.001.</p><p>CPK MB, creatine phosphokinase-MB; IL-6, interleukin 6; WMSI, wall motion score index; IRA, infarct related artery; LAD, left anterior descending artery; RCA, right coronary artery; LCX, left circumflex artery.</p

Additional file 7 of Stimulants associated with reduced risk of hospitalization for motor vehicle accident injury in patients with obstructive sleep apnea-a nationwide cohort study

Additional file 7: Table S6. Factors of traffic injury by using Cox regression among OSA patients in different treatments