Non-invasive screening for Alzheimer's disease by sensing salivary sugar using Drosophila cells expressing gustatory receptor (Gr5a) immobilized on an extended gate ion-sensitive field-effect transistor (EG-ISFET) biosensor
Lau H.-C.,Kyungpook National University |
Lee I.-K.,Kwangwoon University |
Ko P.-W.,Daegu Medical Center |
Lee H.-W.,Kyungpook National University |
And 3 more authors.
PLoS ONE | Year: 2015
Body fluids are often used as specimens for medical diagnosis. With the advent of advanced analytical techniques in biotechnology, the diagnostic potential of saliva has been the focus of many studies. We recently reported the presence of excess salivary sugars, in patients with Alzheimer's disease (AD). In the present study, we developed a highly sensitive, cell-based biosensor to detect trehalose levels in patient saliva. The developed biosensor relies on the overexpression of sugar sensitive gustatory receptors (Gr5a) in Drosophila cells to detect the salivary trehalose. The cell-based biosensor was built on the foundation of an improved extended gate ion-sensitive field-effect transistor (EG-ISFET). Using an EGISFET, instead of a traditional ion-sensitive field-effect transistor (ISFET), resulted in an increase in the sensitivity and reliability of detection. The biosensor was designed with the gate terminals segregated from the conventional ISFET device. This design allows the construction of an independent reference and sensing region for simultaneous and accurate measurements of samples from controls and patients respectively. To investigate the efficacy of the cell-based biosensor for AD screening, we collected 20 saliva samples from each of the following groups: participants diagnosed with AD, participants diagnosed with Parkinson's disease (PD), and a control group composed of healthy individuals. We then studied the response generated from the interaction of the salivary trehalose of the saliva samples and the Gr5a in the immobilized cells on an EG-ISFET sensor. The cell-based biosensor significantly distinguished salivary sugar, trehalose of the AD group from the PD and control groups. Based on these findings, we propose that salivary trehalose, might be a potential biomarker for AD and could be detected using our cell-based EG-ISFET biosensor. The cell-based EG-ISFET biosensor provides a sensitive and direct approach for salivary sugar detection and may be used in the future as a screening method for AD Copyright: © 2015 Lau et al.
Choi J.H.,Gyeongsang National University |
Park S.W.,Sungkyunkwan University |
Chung H.Y.,Kyungpook National University |
Choi K.Y.,Kyungpook National University |
And 8 more authors.
Dermatologic Surgery | Year: 2010
The authors have indicated no significant interest with commercial supporters. © 2010 by the American Society for Dermatologic Surgery, Inc.
Hong N.S.,Kyungpook National University |
Kim J.-G.,Gachon University |
Lee Y.-M.,Kyungpook National University |
Kim H.-W.,Daegu Medical Center |
And 4 more authors.
BMC Endocrine Disorders | Year: 2014
Background: Despite the consistent relationship between serum γ-glutamyltransferase (GGT) and type 2 diabetes (T2D), one unsolved issue is the role of serum GGT in the well-known association between obesity and T2D. This study was performed to investigate whether the association between body mass index (BMI) and impaired fasting glucose (IFG) differed depending on serum GGT levels within the normal range.Methods: Study subjects were 2,424 men and 3,652 women aged ≥ 40, participating in the Fifth Korean National Health and Nutrition Examination Survey. Serum GGT levels within the normal range were classified into gender-specific tertiles.Results: Among men and women belonging to the lowest tertile of serum GGT, BMI showed statistically non-significant weak associations with the risk of IFG. However, among persons in the highest tertile of serum GGT, the risk of IFG was 3 - 4 times higher among persons with BMI ≥ 25 kg/m2 than those with BMI < 23 kg/m2 (Pinteraction = 0.032 in men and 0.059 in women).Conclusions: The well-known strong association between BMI and IFG was observed mainly among persons with elevation of serum GGT to certain physiological levels, suggesting a critical role of serum GGT in the pathogenesis of IFG. This finding has an important clinical implication because serum GGT can be used to detect high-risk obese persons. © 2014 Hong et al.; licensee BioMed Central Ltd.
Ha E.Y.,Keimyung University |
Bang J.-H.,Keimyung University |
Son J.N.,Keimyung University |
Cho H.-C.,Daegu Medical Center |
Mun K.-C.,Keimyung University
Molecular Medicine Reports | Year: 2010
Carbamylation is a post-translational modification, the pathophysiological consequences of which remain poorly understood. MicroRNAs (miRNAs) are endogenous non-coding small ribonucleic acids that have emerged as one of the central players in gene expression regulation. This study was designed to determine the effect of carbamylated albumin (cAlb) on the expression of miRNAs. Albumin was carbamylated, and the extent of carbamylation was monitored using trinitrobenzenesulphonic acid. Albumin or cAlb were added to rat mesangial cells (RMCs), and RNA was extracted. miRNA microarray analysis was performed. The expression of microRNA-146a (miR-146a) and microRNA-146b (miR-146b) was analyzed by real-time RT-PCR. Of 365 miRNAs analyzed, the expression of miR-146a/b was found to be markedly induced by cAlb (miR-146a, 12.75-fold increase; miR-146b, 5.88-fold increase). Real-time RT-PCR analysis confirmed the increased levels of miR-146a/b by cAlb (p<0.05). It was also found that expression levels of miR-146a/b were increased in renal cell carcinoma tumor tissues compared to corresponding non-tumor tissues (p<0.05). Our data suggest that cAlb stimulates miR-146a/b in RMCs, the levels of which are increased in renal cell carcinoma. Further studies on the function of cAlb may provide new insights into the pathophysiology of renal cell carcinoma.
Synergistic interaction between polycyclic aromatic hydrocarbons and environmental tobacco smoke on the risk of obesity in children and adolescents: The U.S. National Health and Nutrition Examination Survey 2003-2008
Kim H.-W.,Daegu Medical Center |
Kam S.,Kyungpook National University |
Lee D.-H.,Kyungpook National University
Environmental Research | Year: 2014
Background: Polycyclic aromatic hydrocarbons (PAHs) may be obesogens. However, the role of PAHs independent of environmental tobacco smoke (ETS) is unclear, and the interaction between PAHs and ETS remains unknown. Methods: We performed cross-sectional analyses of urinary concentrations of PAH metabolites, body mass index (BMI), and waist circumference (WC) in 1985 people aged 6-18 years using data from the 2003-2008 U.S. National Health and Nutrition Examination Survey. ETS exposure level was measured as serum cotinine level. Results: PAH metabolites were positively associated with BMI and WC in both the ETS-unexposed and ETS-exposed groups. The adjusted odds ratios for general obesity defined by age- and sex-specific BMI≥95th percentile across the quartiles of total PAH metabolites were 1, 4.51, 2.57, and 8.09 (Ptrend=0.003) in the ETS-unexposed group and 1, 2.02, 1.83, and 3.86 (Ptrend<0.001) in the ETS-exposed group. However, the association of PAH metabolites with obesity became stronger as serum cotinine levels increased (Pinteraction<0.05). Among those with high ETS exposure, the adjusted odds ratios for general obesity across quartiles of total PAH metabolites were 1, 2.89, 5.26, and 16.29 (Ptrend<0.001). Compared to the low PAH-exposure group without exposure to ETS, the high ETS- and high PAH-exposure group had 33.85- and 17.64-fold greater risks of general and central obesity, respectively. Conclusion: Environmental exposure to PAHs may be associated with childhood obesity irrespective of ETS. In particular, simultaneous exposure to PAHs and ETS may substantially increase the risk of obesity. © 2014 Elsevier Inc.