Detection of Cartilage Oligomeric Matrix Protein Using a Quartz Crystal Microbalance

Current methods for diagnosing early stage osteoarthritis (OA) based on the magnetic resonance imaging and enzyme-linked immunosorbent assay methods are specific, but require specialized laboratory facilities and highly trained personal to obtain a definitive result. In this work, a user friendly and non-invasive quartz crystal microbalance (QCM) immunosensor method has been developed to detect Cartilage Oligomeric Matrix Protein (COMP) for early stage OA diagnosis. This QCM immunosensor was fabricated to immobilize COMP antibodies utilizing the self-assembled monolayer technique. The surface properties of the immunosensor were characterized by its FTIR and electrochemical impedance spectra (EIS). The feasibility study was based on urine samples obtained from 41 volunteers. Experiments were carried out in a flow system and the reproducibility of the electrodes was evaluated by the impedance measured by EIS. Its potential dynamically monitored the immunoreaction processes and could increase the efficiency and sensitivity of COMP detection in laboratory-cultured preparations and clinical samples. The frequency responses of the QCM immunosensor changed from 6 kHz when testing 50 ng/mL COMP concentration. The linear regression equation of frequency shift and COMP concentration was determined as: y = 0.0872 x + 1.2138 (R2 = 0.9957). The COMP in urine was also determined by both QCM and EIS for comparison. A highly sensitive, user friendly and cost effective analytical method for the early stage OA diagnosis has thus been successfully developed

Camphoratins A−J, Potent Cytotoxic and Anti-inflammatory Triterpenoids from the Fruiting Body of Taiwanofungus camphoratus

Ten new triterpenoids, camphoratins A–J (1–10), along with 12 known compounds were isolated from the fruiting body of Taiwanofungus camphoratus. Their structures were established by spectroscopic analysis and chemical methods. Compound 10 is the first example of a naturally occurring ergosteroid with an unusual cis-C/D ring junction. Compounds 2–6 and 11 showed moderate to potent cytotoxicity with EC50 values ranging from 0.3 to 3 μM against KB and KB-VIN human cancer cell lines. Compounds 6, 10, 11, 14–16, 18, and 21 exhibited anti-inflammatory NO-production inhibition activity with IC50 values of less than 5 μM, which was more potent than the nonspecific NOS inhibitor Nω-nitro-L-arginine methyl ester (L-NAME)

Five New Iridoids from Roots of Salvia digitaloides

Five new iridoids, salvialosides A–E (compounds 1–5), together with fifty known compounds were isolated from the roots of Salvia digitaloides. The structures of the new compounds were completely elucidated using a combination of 2D NMR techniques (COSY, NOESY, HMQC and HMBC) and HR-ESI-MS analyses. The known compounds were identified by comparison of their spectroscopic and physical data with those reported in the literature

Peptide-based antifouling aptasensor for cardiac troponin I detection by surface plasmon resonance applied in medium sized Myocardial Infarction

Highly selective and sensitive detection of cardiac troponin I (cTnI) is a powerful complement to clinical diagnosis of acute myocardial infarction (AMI). In this study, a strategy for cTnI detection was developed by constructing a universal biosensing interface composed of zwitterionic peptides and aptamers. The peptides were self-assembled onto gold chips, and some of them were biotinylated. The cTnI-specific binding aptamers were immobilized through the streptavidin-biotin system. Surface plasmon resonance (SPR) measurements revealed the preparation process. The developed aptasensor presents a linear detection with cTnI ranging from 20 ng/ml to 600 ng/ml and a detection limit of 20 ng/ml. The high immobilization of the aptamer enhances the sensitivity of the aptasensor and the calculated KD was 6.75 nM. Due to the outstanding antifouling property of the zwitterionic peptide, the developed aptasensor possesses a high resistance towards protein fouling. Moreover, the aptasensor has excellent selectivity and specificity towards cTnI in complex media. Hence, the proposed peptide-based aptasensor shows great potential for practical application in medium sized Myocardial Infarction (MI)

CAUSAL MODELING OF WEB-ADVERTISING EFFECTS BY IMPROVING SEM BASED ON DEMATEL TECHNIQUE

Causal analysis greatly affects the efficiency of decision-making. Scholars usually adopt structural equation modeling (SEM) to establish a causal model recently. However, statistical data allow researchers to modify the model frequently to arrive at good model fitness, and SEM is often misapplied when the data are merely fitted to an SEM and the theory is then extended from the analytical result based on presumed hypotheses. This paper proposed SEM modified by DEMATEL technique, taking causal model of Web-advertising effects for example. Having revealed that the new model is the one that conforms to actual data and is better than initial model, the results confirm that the DEMATEL technique can be an efficient, complementary, and confident approach for reprioritization of the amended modes in a SEM model. In addition, the most important factor affecting the Web-advertising effects may be found via the modified model, which benefits the manager for making strategic marketing plans. </jats:p