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Objectives: To assess retrospectively the diagnostic value of procalcitonin (PCT) in excluding suspected bloodstream infection, establish cut-off values for PCT levels, and compare PCT with other clinical markers., Methods: The predictive accuracy of different continuous parameters was estimated by univariate analysis of the area under the receiver operating characteristic curve. Optimized cut-off points for the parameters were selected according to the maximum Youden index values, which in turn were used to define positive and negative predictive values of different parameters in diagnosing bloodstream infection., Results: The PCT level yielded a statistically significant area under the receiver operating characteristic curve of 0.765, with a best cut-off value of 0.80 ng/ml (83% sensitivity; 65% specificity, Youden index, J = 0.48). Positive and negative predictive values at this cut-off value were 38% and 94%, respectively. Mann-Whitney U-test revealed significantly higher values for PCT, C-reactive protein and percentage of neutrophils, but not for white blood cell count, in patients with bloodstream infection., Conclusions: The serum PCT level can potentially be used as surrogate marker to exclude bacteraemia and to inform critical management decisions regarding antibiotic usage, in patients admitted with suspected bloodstream infection.

A label-free photoelectrochemical (PEC) immunoassay system based on the one-step synthesis of SnS2/CdS nanocomposites is successfully constructed for sensitively analyzing procalcitonin (PCT). The one-step synthesis of SnS2/CdS enables the rapid construction of an immunoassay system and avoids the waste of energy. In the constructed immunoassay system, CdS as a sensitizer for PCT analysis not only enhances the light absorption of SnS2 as a photocurrent generator but also can accelerate the separation of photosensitive electrons and holes by forming a heterostructure. Under optimum conditions, the energy-saving assay platform based on the enhancement photocurrent response of SnS2/CdS nanocomposites exhibited an excellent performance in analyzing a series of PCTs with different concentrations in a wide linear range of 0.5 pg mL−1 to 100 ng mL−1 and the detection limit was 0.17 pg mL−1. In view of the advantages of good selectivity, high sensitivity, and facile preparation procedure, the PEC immunoassay is expected to be a promising analytical platform for rapid analysis of PCT and other biomarkers in clinical medical samples. [ABSTRACT FROM AUTHOR]

The article offers information on the role of Yes-Associated Protein (YAP) on vandetanib resistance in medullary thyroid cancer, providing basis for combating MTC with YAP inhibitor and vandetanib. It discusses that Rearranged in Transformation mutations as one of the major drivers of medullary thyroid cancer.

In this paper, we report a novel multiple amplification strategy for ultrasensitive near-infrared electrochemiluminescence (ECL) immunoassay in K 2 S 2 O 8 solution. The realization of this strategy is based on the antenna effect of Eu-MOF (EuBTC) and a high efficiency catalysis of CoS 2 hollow triple shelled nanoboxes (TSNBs). The H 3 BTC ligand in the antenna effect first undergoes π-π* absorption and a singlet-singlet electronic transition. Its energy passes through the intersystem to the triplet state, next transfers from the lowest excited triplet state to the vibrational energy level of the rare earth ion, finally realizing sensitizing center ion luminescence. Moreover, ionic reaction and structural advantages endow CoS 2 TSNBs a dual signal enhancement effect. This sandwich-type ECL biosensor has a near-infrared luminescence in 800–900 nm, thus avoiding damage to the sample in the meantime. In practical diagnosis, the normal critical value of procalcitonin (PCT) (<0.5 ng/mL) is much higher than the detection limit (3.65 fg/mL) and is in the detection range (10 fg/mL-100 ng/mL), which means that the ECL biosensor has a high sensitivity in the detection of PCT and meet the requirement for diagnosis of disease completely. Therefore, the strategy provides a feasible method for efficient and stable analysis of systemic inflammatory response such as fearful bacterial infection, hepatitis B, and peritonitis. • A novel near-infrared ECL biosensor was constructed to realize non-damage detection. • The EuBTC with special antenna effect as luminophore owned stronger and steadier property. • Complex hollow triple shelled nanoboxes structure catalyst containing only one component greatly boosted ECL intensity. [ABSTRACT FROM AUTHOR]

• It was the first application of GaON in PEC immunosensors. • An effectively cascade-like energy band edge level was obtained, which can effectively amplified PEC response. • The BiVO 4 /GaON/CdS label-free PEC immunosensor was successfully developed for determination of procalcitonin. In this paper, GaON with excellent photoelectrochemical (PEC) performance was adopted in PEC immunosensor for the first time. Based on CdS sensitized BiVO 4 /GaON composite material, a label-free PEC immunosensor was successfully developed for determination of procalcitonin (PCT). Firstly, BiVO 4 nanoarray was prepared by electrodeposition. Then GaON was added to form the BiVO 4 /GaON composite material, due to the greatly increasing charge transfer efficiency, the PEC signal increased by about 3 times. At last, CdS grew in situ on BiVO 4 /GaON composite that further expanded the light absorption range and improved the light utilization, and the PEC signal further increased again. This PEC immunosensor has a good linear relationship of 0.1 pg mL−1 - 50 ng mL−1 and the detection limitation of 0.03 pg mL−1 is calculated. Importantly, the BiVO 4 /GaON/CdS immunosensor platform showed good specificity and stability, and serum sample analysis have been performed with satisfactory results. [ABSTRACT FROM AUTHOR]

• This split-type sensor separates the two processes of antigen-antibody specific recognition and photoelectric conversion. • THCH as extra electron donor is released through the controlled-release strategy. • CdS sensitized Bi 2 Sn 2 O 7 forms a heterojunction as the matrix to provide basic PEC response effectively. • The biosensor for sensitive detection PCT exhibited the detection limit of 0.17 pg/mL. A split-type photoelectrochemical (PEC) sensor for procalcitonin (PCT) detection was successfully prepared. This split-type sensor adopted controlled-release strategy, which separated the two processes of antigen-antibody specific recognition and photoelectric conversion, so that the two processes can be performed independently. In addition, CdS sensitized Bi 2 Sn 2 O 7 is combined for the first time to form a heterojunction as the matrix to provide the basic PEC response, which could effectively absorb visible-light, and reduced electron-hole pair recombination, ensured the stability of the sensor. Distinctly important, the skillfully process was performed in a 96-well plate where the specific reaction was completed proceeded between antigen and antibody. For improving sensitivity of the sensor, acetylcholinesterase (ACHE) connected to SiO 2 nanospheres (SiO 2 NSs) modified by second antibody (Ab 2 -ACHE@SiO 2 NSs) was designed, the thiocholine (THCH) can be released when acetylthiocholine iodide (ATCH) exists, and the THCH as an electron donor could enhance PEC response. The proposed PEC immunoassay with high-performance photosensitive materials, and the smart electron donor released strategy have a wide detection liner range from 0.0005 to 100 ng/mL with a low detection limit of 0.17 pg/mL, also provide great clinical diagnostic potential for other target proteins. [ABSTRACT FROM AUTHOR]

• The signal indicator and matrix, Fe 3 S 4 -Pd, displayed excellent electrocatalytic activity for H 2 O 2 redox reaction. • Magnetic glassy carbon electrode was used to firmly immobilized the magnetic Fe 3 S 4 -Pd to achieve satisfied stability. • PBG nanomaterial played a role as the electron blocking label that realized a sensitive variation of current signal. • The signal-off sensing platform was successfully constructed, with a low detection limit of 130 fg/mL. Herein, a sandwich-type electrochemical (EC) immunosensor is proposed based on a special signal-off mode for the sensitive detection of procalcitonin (PCT) by utilizing Fe 3 S 4 loaded with Pd nanoparticles (Fe 3 S 4 -Pd) as a signal indicator and matrix and functionalized pineal mesoporous bioactive glass (PBG) as the label for signal amplification. Fe 3 S 4 -Pd not only shows excellent electrocatalytic activity for the H 2 O 2 redox reaction but is also firmly immobilized on a magnetic glassy carbon electrode due to its excellent magnetic properties; because of the above features, this immunosensor exhibits excellent sensitivity and stability, respectively. Glutaraldehyde is used as a cross-linking agent to bond the secondary antibodies (Ab 2) with PBG. It is worth mentioning that the electron transfer rate between the electrolyte and electrode is decreased significantly by PBG-Ab 2 ; thus, a sensitive variation in the current signal is observed, and a further improvement in the sensitivity of the immunosensor is realized. More importantly, the proposed signal-off sensing system has a wide linear detection range of 500 fg/mL to 50 ng/mL for PCT and a low detection limit of 130 fg/mL, which promotes it as a promising detection method for the sensitive detection of other biomarkers. [ABSTRACT FROM AUTHOR]