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Background: Bladder cancer is a common malignant disease in developed countries. Early detection of malignancy is important using urine cytology. The 5-aminolevulinic acid (ALA)-based photodynamic diagnosis (ALA-PDD) has not been routinely applied in urine cytology analysis yet, although it has been well accepted for tumor lesion marking in cystoscopy., Methods: A total of eight volunteers were enrolled in this study. The cells of sediment suspension from bladder washing fluid and random urine were stained by ALA-induced protoporphyrin IX (ALA-PpIX) and the fluorescent intensity of ALA-PpIX was analyzed by ImageJ., Results: The cutoff value of fluorescent intensity was 90.260 per pixel. The proposed protocol provided an objective fluorescent intensity for evaluation. Sensitivity was 0.931 and specificity was 1.000., Conclusions: The staining procedure applied was ALA-PpIX for suspicious cells in the cellular suspension from bladder wash fluid and random urine. ImageJ was applied to the objective measurement for the fluorescent intensity of the stained cells. The cutoff value for the positive result was 90.260 per pixel. Therefore, the protocol proposed in this study provides a potential means to enhance accuracy for urine cytology analysis., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier B.V.)

Urinary sediment is used to evaluate patients with possible urinary tract diseases. Currently, numerous protocols are applied to detect dysmorphic red blood cells (RBCs) and renal tubular epithelial cells (RTECs) in urinary sediment. However, distinct protocols are used by nephrologists and medical technologists for specimen concentration and observation, which leads to major discrepancies in the differential counts of formed elements such as dysmorphic RBCs and RTECs and might interfere with an accurate clinical diagnosis. To resolve these problems, we first tested a modified urinalysis protocol with an increased relative centrifuge force and concentration factor in 20 biopsy-confirmed glomerulonephritis patients with haematuria. We successfully improved the recovery ratio of dysmorphic RBCs in clinical specimens from 34.7% to 42.0% (P < 0.001). Furthermore, we confirmed the correlation between counts by the modified urinary protocol and Sysmex UF-1000i urinary flow cytometer (r ≥ 0.898, P < 0.001). A total of 28 types of isomorphic and dysmorphic RBCs were detected using a bright field microscope, with results comparable to those using a standard phase contrast microscope. Finally, we applied Sternheimer stain to enhance the contrast of RTECs in the urinary sediments. We concluded that this modified urinalysis protocol significantly enhanced the quality of urinalysis.

Aims: Myostatin is a negative regulator of skeletal muscle mass and may also modulate energy metabolism secondarily. We aim to investigate the relationship between serum myostatin and the metabolic variables in diabetic (DM) and non-diabetic subjects., Materials and Methods: A cross-sectional study recruiting 246 consecutive DM patients and 82 age- and gender-matched non-diabetic individuals at a medical center was conducted. The variables of anthropometry and blood chemistry were obtained. Serum myostatin level was measured with enzyme immunoassay., Results: DM group had lower serum myostatin compared with non-diabetics (7.82 versus 9.28 ng/ml, p<0.01). Sixty-two percent of the recruited individuals had metabolic syndrome (MetS). The patients with MetS had significantly lower serum myostatin than those without (7.39 versus 9.49 ng/ml, p<0.001). The serum myostatin level decreased with increasing numbers of the MetS components (p for trend<0.001). The patients with higher body mass index, larger abdominal girth, lower high-density lipoprotein cholesterol (HDL-C), and higher triglycerides had lower serum myostatin than those without. The serum myostatin level was independently negatively related to larger abdominal girth, higher triglycerides, and lower HDL-C after adjustment. The odds ratios for MetS, central obesity, low HDL-C, high triglycerides, and DM were 0.85, 0.88, 0.89, 0.85, and 0.92, respectively, when serum myostatin increased per 1 ng/mL, in the binary logistic regression models., Conclusions: Lower serum myostatin independently associated with MetS, central obesity, low HDL-C, and high triglycerides after adjustment. Higher serum myostatin is associated with favorable metabolic profiles.

ELISA and ELISPOT methods are utilized for interferon-gamma (IFN-γ) release assays (IGRAs) to detect the IFN-γ secreted by T lymphocytes. However, the multi-step protocols of the assays are still performed with laboratory instruments and operated by well-trained people. Here, we report a membrane-based microfluidic device integrated with a surface plasmon resonance (SPR) sensor to realize an easy-to-use and cost effective multi-step quantitative analysis. To conduct the SPR measurements, we utilized a membrane-based SPR sensing device in which a rayon membrane was located 300 μm under the absorbent pad. The basic equation covering this type of transport is based on Darcy's law. Furthermore, the concentration of streptavidin delivered from a sucrose-treated glass pad placed alongside the rayon membrane was controlled in a narrow range (0.81 μM ± 6%). Finally, the unbound molecules were removed by a washing buffer that was pre-packed in the reservoir of the chip. Using a bi-functional, hairpin-shaped aptamer as the sensing probe, we specifically detected the IFN-γ and amplified the signal by binding the streptavidin. A high correlation coefficient (R(2) = 0.995) was obtained, in the range from 0.01 to 100 nM. A detection limit of 10 pM was achieved within 30 min. Thus, the SPR assay protocols for IFN-γ detection could be performed using this simple device without an additional pumping system.

Objective: To evaluate a novel surface plasmon resonance (SPR) system for the direct measurement of tumor marker carbohydrate antigen 15-3 (CA15-3) in human saliva., Design and Methods: We measured the presence of the tumor marker carbohydrate antigen 15-3 (CA15-3) in human saliva using 2 different surface plasmon resonance (SPR) systems. To compare the sensitivity of an SPR biosensor based on thin-film Au/ZnO and the Biacore SPR system, we prepared CA15-3 samples in saliva and analyzed intensity responses to the samples at various concentrations of CA15-3., Results: The linear detection range of CA15-3 in human saliva with the SPR system based on thin-film Au/ZnO was 2.5-20 U/mL (the cut-off point in cancer patients is around 4 U/mL). The linear range with the Biacore SPR system was 40-300 U/mL., Conclusions: These results show that thin-film Au/ZnO-based SPR systems have higher sensitivity and can be used for measuring the levels of CA15-3 in human saliva without concentrating the samples., (Copyright © 2012 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.)

We report the development of a surface plasmon resonance sensor based on the silver ion (Ag(+))-induced conformational change of a cytosine-rich, single-stranded DNA for the detection of Ag(+) and cysteine (Cys) in aqueous solutions. In the free state, single-stranded oligonucleotides fold into double-helical structures through the addition of Ag(+) to cytosine–cytosine (C–C) mismatches. However, in the presence of Cys, which competitively binds to Ag(+), the formation of the C–Ag(+)–C assembly is inhibited, resulting in free-state, single-stranded oligonucleotides. To enhance sensitivity, the DNA intercalator, daunorubicin, was employed to achieve signal enhancement. The detection limit for Ag(+) was 10 nM with a measurement range of 50–2,000 nM, and the detection limit for Cys was 50 nM with a measurement range of 50–2,000 nM. This simple assay was also used to individually determine the spiked Ag(+) concentration in water samples and Cys concentrations in biological fluid samples.

We report that gold/zinc oxide (Au/ZnO) nanocomposite films were effectively employed to enhance the performance of surface plasmon resonance (SPR) for the detection of tumor markers. Carbohydrate antigen 15.3 (CA15-3), a tumor marker for breast cancer, was chosen as a model analyte. We analyzed intensity response to the samples at various concentrations (0.0125 U/mL to 160 U/mL) in pleural fluid to evaluate the detection capability of the SPR biosensor based on Au/ZnO thin films. The linear range extended from 1 to 40 U/mL with a correlation coefficient of R(2) = 0.991 and a limit of detection reaching 0.025 U/mL at a signal-to-noise ratio of 3:1. Compared with the degree of the shift in SPR intensity induced by the specific binding event between antibody and antigen, the change of intensity on the Au/ZnO layers was increased by at least 2 fold over that on the gold/chromium (Au/Cr) layers. In addition, we determined that the Au/ZnO layers allowed for a detection limit 4 times lower than the Au/Cr layers, which are in widespread use as the sensing interfaces in current SPR-based detectors. In conclusion, the use of Au/ZnO films greatly enhanced the SPR signal yield for this bimolecular interaction and showed high sensitivity.