Comparison of molecular interactions of Ag2 Te and CdTe quantum dots with human serum albumin by spectroscopic approaches.

Ag2 Te quantum dots (QDs) have attracted great attention in biological applications due to their superior photoluminescence qualities and good biocompatibility, but their potential biotoxicity at a molecular biology level has been rarely discussed. In order to better understand the basic behavior of Ag2 Te QDs in biological systems and compare their biotoxicity to cadmium-containing QDs, a series of spectroscopic measurements was applied to reveal the molecular interactions of Ag2 Te QDs and CdTe QDs with human serum albumin (HSA). Ag2 Te QDs and CdTe QDs statically quenched the intrinsic fluorescence of HSA by electrostatic interactions, but Ag2 Te QDs exhibited weaker quenching ability and weaker binding ability compared with CdTe QDs. Electrostatic interactions were the main binding forces and Sudlow's site I was the primary binding site during these binding interactions. Furthermore, micro-environmental and conformational variations of HSA were induced by their binding interactions with two QDs. Ag2 Te QDs caused less secondary structural and conformational change in HSA, illustrating the lower potential biotoxicity risk of Ag2 Te QDs. Our results systematically indicated the molecular binding mechanism of Ag2 Te QDs with HSA, which provided important information for possible toxicity risk of these cadmium-free QDs to human health.

Novel N-Doped Carbon Dots/ß-Cyclodextrin Nanocomposites for Enantioselective Recognition of Tryptophan Enantiomers.

Based on N-doped carbon dots/ß-cyclodextrin nanocomposites modified glassy carbon electrodes (N-CDs/ß-CD/GCE), an effective electrochemical sensor for enantioselective recognition of tryptophan (Trp) enantiomers was developed by differential pulse voltammograms (DPVs). Fluorescent N-CDs were synthesized through a hydrothermal method and characterized by spectroscopic approaches. The N-CDs/ß-CD nanocomposites were efficiently electrodeposited on the surface of GCE through C-N bond formation between N-CDs and electrode. The obtained N-CDs/ß-CD/GCE was characterized by multispectroscopic and electrochemical methods. Such N-CDs/ß-CD/GCE generated a significantly lower Ip and more negative Ep in the presence of l-Trp in DPVs, which was used for the enantioselective recognition of Trp enantiomers. The N-CDs/ß-CD nanocomposites showed different binding constants for tryptophan enantiomers, and they further selectively bonded with l-Trp to form inclusion complexes. This N-CDs/ß-CD/GCE combined advantages of N-CDs with strong C-N binding ability and ß-CD with specific recognition of Trp enantiomers to fabricate a novel sensing platform for enantioselective recognition of Trp enantiomers. This strategy provided the possibility of using a nanostructured sensor to discriminate the chiral molecules in bio-electroanalytical applications.

Electrochemiluminescence of luminol at the titanate nanotubes modified glassy carbon electrode.

A new strategy for the construction of a sensitive and stable electrochemiluminescent platform based on titanate nanotubes (TNTs) and Nafion composite modified electrode for luminol is described, TNTs contained composite modified electrodes that showed some photocatalytic activity toward luminol electrochemiluminescence emission, and thus could dramatically enhance luminol light emission. This extremely sensitive and stable platform allowed a decrease of the experiment electrochemiluminescence luminol reagent. In addition, in luminol solution at low concentrations, we compared the capabilities of a bare glassy carbon electrode with the TNT composite modified electrode for hydrogen peroxide detection. The results indicated that compared with glassy carbon electrode this platform was extraordinarily sensitive to hydrogen peroxide. Therefore, by combining with an appropriate enzymatic reaction, this platform would be a sensitive matrix for many biomolecules.

Infectious mononucleosis in children and differences in biomarker levels and other features between disease caused by Epstein-Barr virus and other pathogens: a single-center retrospective study in China.

Background: Infectious mononucleosis (IM) is a common viral infection that typically presents with fever, pharyngitis and cervical lymphadenopathy. Our aim was to identify the different pathogens causing IM in children admitted to our hospital and to analyze the differences in features of infection with different organisms. Methods: We retrospectively analyzed the data of children aged 0-17 years admitted to Wuhan Children's Hospital during 2013-2022 with IM. We compared symptoms, physical findings, blood counts, and serum biomarkers between patients with IM due to Epstein-Barr virus (EBV) and IM due to other pathogens. Results: Among 1480 enrolled children, 1253 (84.66%) had EBV infection, 806 (54.46%) had M. pneumoniae infection, 796 (53.78%) had cytomegalovirus infection, 159 (10.74%) had parvovirus infection, 38 (2.57%) had influenza virus infection, and 25 (1.69%) had adenovirus infection. Receiver operating characteristic curves were used to determine the area under the curve for alanine transaminase (ALT), aspartate transaminase (AST), Alkaline phosphatase (ALP), total bilirubin (TBil), indirect bilirubin (IBil) levels to assess liver damage, and for creatine kinase (CK), CK-MB, and lactate dehydrogenase (LDH) levels to assess myocardial damage. The optimal cutoff values of these biomarkers were then determined. In multivariate analysis, elevated ALT, AST, ALP, TBil, and IBil were independently associated with liver damage, and age <3 years, CK, CK-MB, and LDH with myocardial damage. Conclusion: Evaluation of biomarkers and pathogen detection may help physicians to take preventive actions to avoid serious complications in children with infectious mononucleosis.

Genome-wide association studies-derived susceptibility loci in type 2 diabetes: confirmation in a Chinese population.

PURPOSE: Several novel genetic variants for type 2 diabetes mellitus (T2DM) have been identified through genome-wide association studies (GWAS). A case-controll study was performed to investigate the association of five new European or South Asian GWAS-derived susceptibility loci with T2DM in a Chinese population. METHODS: Five single nucleotide polymorphisms (SNPs) were genotyped: rs3923113 near GRB14, rs16861329 in ST6GAL1, rs1802295 in VPS26A, rs7178572 in HMG20A, and rs231362 near KCNQ1, by high-resolution melting (HRM) of small amplicons. The association between T2DM and related quantitative traits in a total of 900 Chinese individuals, including 498 type 2 diabetic patients and 402 ethnically matched control subjects, were examined. RESULTS: After adjusting for age and gender, rs1802295 (OR 5.724, P=0.03) and rs231362 (OR=5.683, P=0.016) were found to be associated with T2DM. Triglyceride levels were higher in TT and CT carriers for rs16861329 (1.05 (0.8-1.34) mmol/l) than in CC carriers (0.91 (0.73-1.23) mmol/l) with P=0.008 and that high-density lipoprotein cholesterol (HDL-C) was lower in TT and CT carriers (1.17 (1.02-1.33) mmol/l) than in CC carriers (1.21 (1.05-1.41) mmol/l), with P=0.034. For rs3923113, the HDL-C levels were lower in the GG carriers (1.08 (0.90-1.18) mmol/l) than in the GT+TT carriers (1.21 (1.04-1.38) mmol/l), with P=0.018. Ours is the first report of this association. CONCLUSION: rs231362-KCNQ1 and rs1802295-VPS26A are associated with T2DM in the Chinese population. The remaining three SNPs are associated with other aspects of lipid metabolism.

Manifestations of blood coagulation and its relation to clinical outcomes in severe COVID-19 patients: Retrospective analysis.

INTRODUCTION: Characteristics of blood coagulation and its relation to clinical outcomes in COVID-19 patients are still rarely reported. We aimed to investigate the blood coagulation function and its influences on clinical outcomes of patients with syndrome coronavirus 2 (SARS-CoV-2) infection. METHODS: A total of 71 severe patients with confirmed SARS-CoV-2 infection who were treated in Wuhan First Hospital from February 12 to March 20, 2020, were enrolled. The blood coagulation data in these patients and in 61 healthy controls were collected. The patients with COVID-19 were divided into two groups: the aggravated group and the nonaggravated group, respectively, basing on whether the patients' conditions turned to critically ill or not after admission. RESULTS: Compared with healthy controls, patients with COVID-19 had significant performances with coagulation dysfunction, including dramatically elevated values of FIB, PT, APTT, INR, FDP, and D-Dimers but markedly reduced AT value (P < .05). Importantly, more noteworthy coagulation disorders similar to the differences between patients and controls were found in the aggravated patients with conditions deterioration after admission than those in the nonaggravated patients without conditions deterioration (P < .05). Moreover, the aggravated patients possessed a longer hospital stay and a higher mortality compared with the nonaggravated patients (P < .001). The coagulation parameters of COVID-19 patients were widely and closely related to the indexes of liver function and inflammation (P < .05), indicating the coagulation dysfunction of these patients may be caused by liver injury and inflammatory storm. CONCLUSION: Severe patients with SARS-CoV-2 infection often possess coagulation dysfunction on admission. A certain correlation exists in coagulation disorder and adverse clinical outcome among severe COVID-19 patients.

Study on the molecular interaction of graphene quantum dots with human serum albumin: combined spectroscopic and electrochemical approaches.

Graphene quantum dots (GQDs) have attracted great attention in biological and biomedical applications due to their super properties, but their potential toxicity investigations are rarely involved. Since few studies have addressed whether GQDs could bind and alter the structure and function of human serum albumin (HSA), the molecular interaction between GQDs and HSA was systematically characterized by the combination of multispectroscopic and electrochemical approaches. GQDs could quench the intrinsic fluorescence of HSA via static mode. The competitive binding fluorescence assay revealed that the binding site of GQDs was site I of HSA. Some thermodynamic parameters suggested that GQDs interacted with HSA mainly through van der Waals interactions and hydrogen bonding interactions, and protonation might also participate in the process. As further revealed by FT-IR spectroscopy and circular dichroism technique, GQDs could cause the global and local conformational change of HSA, which illustrated the potential toxicity of GQDs that resulted in the structural damage of HSA. Electrochemical techniques demonstrated the complex formation between GQDs and HSA. Our results offered insights into the binding mechanism of GQDs with HSA and provided important information for possible toxicity risk of GQDs to human health.

FADS gene polymorphisms confer the risk of coronary artery disease in a Chinese Han population through the altered desaturase activities: based on high-resolution melting analysis.

OBJECTIVE: We explored the desaturase activities and the correlation of fatty acid desaturases (FADS) gene single nucleotide polymorphisms (SNPs) with plasma fatty acid in coronary artery disease (CAD) patients in a Chinese Han population. METHODS: Plasma fatty acids were measured by gas chromatography in CAD patients (n = 505) and a control group (n = 510). Five SNPs in the FADS gene were genotyped with high-resolution melting (HRM) methods. RESULTS: After adjustment, D6D activity, assessed as arachidonic acid (AA, C20:4n-6)/linoleic acid (LA, C18:2n-6), was higher in CAD patients (p<0.001). D9D activity, which was estimated as the ratio of palmitoleic acid (C16:1)/palmitic acid (C16:0) or oleic acid (C18:1n-9) to stearic acid (C18:0), was also increased (p<0.001). The genotype distributions of rs174537 G>T and rs174460 C>T were different between the two groups. The rs174537 T allele was associated with a lower risk of CAD [OR 0.743, 95% CI (0.624, 0.884), p = 0.001]. Carriers of the rs174460 C allele were associated with a higher risk of CAD [OR 1.357, 95% CI (1.106, 1.665), p = 0.003]. CONCLUSIONS: We firstly report that the rs174460 C allele is associated with a higher risk of CAD, and confirm that the rs174537 T allele is associated with a lower risk of CAD. Our results indicate that FADS gene polymorphisms are likely to influence plasma fatty acid concentrations and desaturase activities.