In vitro and in vivo detection of lactate with nanohybrid-functionalized Pt microelectrode facilitating assessment of tumor development.

Accelerated glucose uptake and "aerobic glycolysis" of tumor cells generates a high-level lactate in extracellular space and within tumor tissue, which is thought to be a hallmark of tumor and closely correlated with tumor development. Here, we report the development of an enzyme-free electrochemical sensing platform based on a Pt-microneedle electrode functionalized with Au nanoparticles (Au-NPs) decorated polydopamine nanospheres (PDA-NSs), and explore its practical application in in vitro and in vivo detection of lactate in different biological samples. Our results demonstrate that in virtue of the nanostructured merits and high electrocatalytic activity, the resultant nanohybrid-microelectrode exhibits good sensitivity and selectivity to the nonenzymatic electrochemical detection of lactate, with a detection limit of 50 µM, a liner range of 0.375-12 mM, and a sensitivity of 11.25 mA mM-1 cm-2, as well as a good anti-interference ability to other active small molecules. The platform quantifies lactate in complex bio-fluids, including cancerous and non-cancerous cell culture media, as well as serum samples, with detecting time 7.5-fold faster than does a clinically-used approach. Moreover, owing to miniaturized size and satisfactory electrochemical performance, the sensor achieves in vivo recording of lactate-related characteristic voltammetric signals within a living tumor, which are positively correlated with tumor burden and growth. Therefore, the platform cannot only be employed for cancer metabolic investigation, but also potentially for clinical assessment of tumor progression, and even clinical diagnosis of other lactate metabolism disorders.

Performance verification of a new domestic chemiluminescence detection system.

BACKGROUND: Procalcitonin (PCT) is an acute phase response protein, which can be used as an indicator for early diagnosis of infection. At present, the main detection methods for PCT are electrochemiluminescence and enzyme-linked immunofluorescence. We aimed to explore the accuracy of PCT determination in a domestic chemiluminescence detection system and its correlation with other systems. METHODS: Clinical specimens were collected, and the precision, linearity, biological reference interval, contamination rate, Clinical reportable scope, and methodological comparison of the determination of PCT in a Chinese chemiluminescence detection system were evaluated and preliminarily verified by referring to Clinical and Laboratory Standards Institute (CLSI) documents or industry standards. RESULTS: The results of precision verification showed that the coefficient of variation (CV) values of the variation coefficient of precision in the samples of low and high values were 2.07% and 0.83% respectively, while the CV values of the total variation coefficient of precision were 3.05% and 1.81% respectively; these findings all met the experimental requirements. The results of linear verification test showed that the linear range was 0.006-96.96 ng/mL, and the linear relationship was well within the detection range (R2 =0.9891). The biological reference interval and the carrying contamination rate were also verified. The clinical reportable range was 0.02-369.585 ng/mL. The results showed that the correlation coefficient between the Mindray CL900I and the Roche E602 was 0.9986, and that between the Mindray CL900I and the Snibe 2000 was 0.983. Meanwhile, when the PCT was higher than 0.1 ng/mL, the correlation coefficient was 100%. CONCLUSIONS: The domestic chemiluminescence detection system has a good performance in the determination of calcitonin, as indicated by the measures of precision, linearity, biological reference interval, carrying contamination rate, and Clinical reportable scope, and can thus be used for clinical specimen detection. The results of methodological comparison showed that the correlation coefficient between the Mindray CL900I and Roche E602 was 0.9986, while the correlation coefficient between the Mindray CL900I and the Snibe 2000 was 0.983. The test results were consistent with the experimental requirements.

Elevated Serum Matrix Metalloproteinase-9, Interleukin-6, Hypersensitive C-Reactive Protein, and Homocysteine Levels in Patients with Epilepsy.

Neuroinflammation contributes to the occurrence and development of epilepsy. However, several inflammatory factors that are important for facilitating the diagnosis to reduce or prevent seizures need to be further studied. This study is aimed to explore serum levels of matrix metalloproteinase-9 (MMP-9), interleukin-6 (IL-6), hypersensitive C-reactive protein (hs-CRP), and homocysteine (HCY) in epilepsy patients and the relationship of them with epilepsy. Epilepsy patients (n = 101) in the Second Xiangya Hospital from January 2017 to August 2018 were allocated to the epilepsy groups, which were divided into idiopathic epilepsy group (n = 43) and symptomatic epilepsy group (n = 58) according to the pathogeny. Healthy individuals (n = 50) were allocated to the control group. The concentrations of serum MMP-9, IL-6, hs-CRP, and HCY in all samples were detected by enzyme-linked immunosorbent assay, chemiluminescence method, latex-enhanced immunoturbidimetry, and enzyme circulation method. The levels of serum MMP-9, IL-6, hs-CRP, and HCY in epilepsy patients were higher than those in the control group (P < 0.05, P < 0.01, P < 0.01, and P < 0.01, respectively). The levels of serum MMP-9, IL-6, hs-CRP, and HCY in the symptomatic epilepsy group were higher than those in the control group (P < 0.01 or P < 0.05, respectively). The levels of serum MMP-9, IL-6, and hs-CRP in idiopathic epilepsy patients were higher than those in the control group (P < 0.01 or P < 0.05, respectively). The serum HCY level in the idiopathic epilepsy group was lower than that in the symptomatic epilepsy group (P < 0.01). MMP-9, IL-6, hs-CRP, and HCY may be recommended as the state biomarker to distinguish etiology of epilepsy. We hope our study could provide help in some ways for clinical diagnosis and treatment.

Changes of Serum IL-6, IL-17, and Complements in Systemic Lupus Erythematosus Patients.

Cytokines activation and low complement levels are common in systemic lupus erythematosus (SLE) patients. This study is aimed to explore the relationship and clinical significance of cytokines and complements with SLE activity. Serum samples of 140 SLE patients and 36 age- and gender-matched healthy controls (HC) were collected. Serum interleukin (IL)-6, IL-17, high-sensitivity C-reactive proteins (hsCRP), and complements (C3, C4) were measured in all samples. These patients were divided into 3 subgroups based on clinical disease activity with SLE Disease Activity Index 2000 (SLEDAI-2K): stationary status subgroup, mild activity subgroup, and moderate/severe activity subgroup. The serum IL-6, IL-17, and hsCRP levels in SLE patients (4.72 ± 0.28 pg/mL, 23.34 ± 1.32 pg/mL, and 4.78 ± 0.34 mg/mL) were significantly higher than those in the HC group (1.51 ± 0.05 pg/mL, 18.28 ± 1.93 pg/mL, and 1.32 ± 0.29 mg/mL), whereas C3 and C4 levels in SLE patients (0.80 ± 0.28 and 0.21 ± 0.08 g/L) were significantly lower than those in the HC group (1.49 ± 0.08 and 0.36 ± 0.02 g/L). A positive correlation was noted between the SLEDAI-2K scores and serum IL-6, IL-17, and hsCRP levels. These results support the proinflammatory cytokines and complements in the pathogenesis of SLE. The serum IL-6, IL-17, and hsCRP levels were correlated with the disease activity.