Metabolomics Reveal Nanoplastic-Induced Mitochondrial Damage in Human Liver and Lung Cells.

Plastic debris in the global biosphere is an increasing concern, and nanoplastic (NPs) toxicity in humans is far from being understood. Studies have indicated that NPs can affect mitochondria, but the underlying mechanisms remain unclear. The liver and lungs have important metabolic functions and are vulnerable to NP exposure. In this study, we investigated the effects of 80 nm NPs on mitochondrial functions and metabolic pathways in normal human hepatic (L02) cells and lung (BEAS-2B) cells. NP exposure did not induce mass cell death; however, transmission electron microscopy analysis showed that the NPs could enter the cells and cause mitochondrial damage, as evidenced by overproduction of mitochondrial reactive oxygen species, alterations in the mitochondrial membrane potential, and suppression of mitochondrial respiration. These alterations were observed at NP concentrations as low as 0.0125 mg/mL, which might be comparable to the environmental levels. Nontarget metabolomics confirmed that the most significantly impacted processes were mitochondrial-related. The metabolic function of L02 cells was more vulnerable to NP exposure than that of BEAS-2B cells, especially at low NP concentrations. This study identifies NP-induced mitochondrial dysfunction and metabolic toxicity pathways in target human cells, providing insight into the possibility of adverse outcomes in human health.

Wuchuyuamide V, a new amide alkaloid from the fruits of Tetradium trichotomum.

Tetradium trichotomum Lour., is a plant species endemic to tropical South East Asia with particular medicinal importance. However, very little analysis in this plant has been studied up to now from a phytochemical viewpoint. One new amide alkaloid (wuchuyuamide V, 1), as well as two known amide alkaloids-wuchuyuamide III (2), and wuchuyuamide I (3) were obtained from the fruits of T. trichotomum for the first time. The structures of wuchuyuamide V (1) and wuchuyuamide III (2) were unambiguously elucidated by 1D and 2D-NMR spectra, mass spectrometry, and single-crystal X-ray diffraction.

Cathodic electrochemiluminescence at C/CxO(1-x) electrodes for the fabrication of label-free biosensors.

Cathodic electrochemiluminescence (ECL) is firstly observed at a carbon oxide covered glassy carbon (C/C(x)O(1-x)) electrode as a large cathodic pulse polarization is applied. This insulating carbon oxide (C(x)O(1-x)) film is constructed on a glassy carbon (GC) substrate by electrochemical oxidization in basic media. The film properties, such as the composition of carbon and oxygen, and the thickness as well, can be controlled by the potential and the duration in the oxidizing process. X-Ray photoelectron spectroscopy (XPS) studies show that carbonyl and carboxyl dominate at the oxidized surface, to which antibodies can be covalently bound. The specific immunoreaction between antigen (Ag) and antibody (Ab) resulted in a decrease in the ECL intensity, thus creating an interesting basis for the development of a label-free cathodic ECL immunosensor. As an example, human IgG (hIgG) was sensitively determined in the concentration range of 0.01-100 ng mL(-1), and the detection limit was ca. 1.0 pg mL (-1) (S/N = 3). In addition, the content of hIgG in human serum has been assayed by the developed immunosensor and a commercially available immune turbidimetry method, respectively, and consistent results were obtained. The prepared immunosensor provides a promising approach for the clinical determination of IgG levels in human serum, because it is simple, rapid, highly sensitive, specific, and without the need of tedious labeling operations.

Three new quinazolines from Evodia rutaecarpa and their biological activity.

In this research, we investigated the profile and bioactivities of quinazoline alkaloids, a class of natural products boasting multiple bioactivities, from the unripe fruit of Evodia rutaecarpa (Juss.) Benth. Three new quinazoline alkaloids, evodiamide A (1), evodiamide B (2), and evodiamide C (3), as well as eight known quinazolines, were isolated from the MeOH extract of E. rutaecarpa. The new compounds are rare quinazolinedione derivatives with linked heterocyclic nuclei. Among these quinazolines, rhetsinine (8) showed potential as a pesticide and exhibited excellent inhibition against Xanthomonas oryzae pv. oryzae, Xanthomonas oryzae pv. oryzicola, and Xanthomonas campestris pv. campestris, with respective EC50 values of 3.13, 14.32, and 32.72 nmol.

Pro variant of TP53 Arg72Pro contributes to gastric cancer risk in Asians: evidence from a meta-analysis.

BACKGROUND: Previous studies investigating the association between TP53 Arg72Pro polymorphism and gastric cancer (GC) risk in Asian population have reported controversial results. Thus, a meta-analysis was performed. METHODS: A comprehensive literature search was conducted and 17 case-control studies were finally included, involving a total of 5,990 GC cases and 6,812 controls. Subgroup analyses were performed by the sample size. RESULTS: Meta-analysis of all 17 studies showed variant genotypes of TP53 Arg72Pro to be associated with an elevated GC risk in three genetic comparison models (OR(Pro vs. Arg)=1.13, 95%CI 1.03-1.25, P(OR)=0.01; OR(Homozygote comparison model)=1.33, 95%CI 1.07-1.64, P(OR)=0.009; OR(Dominant genetic model)=1.13, 95%CI 1.05-1.22, P(OR)=0.002). Besides, a more obvious association was observed after the heterogeneity was decreased (all P values less than 0.001). This association was further identified by both subgroup and sensitivity analyses. CONCLUSIONS: This meta-analysis suggests the Pro variant of TP53 Arg72Pro contributes to gastric cancer risk in Asians.

Hot electron induced cathodic electrochemiluminescence at AuSb alloy electrode for fabricating immunosensor with self-assembled monolayers.

Thin antimony oxide covered AuSb alloy electrode was firstly found to be an excellent cold cathode for generating hot electrons during cathodic pulse polarization. Owing to the injection of hot electrons and the subsequent generation of hydrated electrons, fluorescein iso-thiocyanate (FITC) that cannot be excited in common ECL was cathodically excited at the alloy electrode. Self-assembled thiol monolayers were formed on the electrode surface due to the presence of Au in the alloy, to which strepavidin was covalently bound, and then biotinylated antibody was immobilized through the strepavidin-biotin interaction. As a simple model, an immunosensor for the detection of human IgG (hIgG) using FITC as labeling agent was fabricated. ECL signals were responsive to the amount of hIgG bounded to the immunosensor. The ECL intensity was linearly changed with the logarithm of hIgG concentration in the range of 1.0-1000 ng mL(-1), and the detection limit was ca. 0.3 ng mL(-1) (S/N=3). The proposed immunosensor showed a broad linear range (three magnitudes), good reproducibility and stability, which is promising in detecting FITC-based labels in various types of bioaffinity assays.

Catalytic electrogenerated chemiluminescence and nitrate reduction at CdS nanotubes modified glassy carbon electrode.

Electrochemical and electrogenerated chemiluminescence (ECL) properties of a glassy carbon electrode modified with CdS nanotubes (CdS-GCE) are investigated in neutral media. The cyclic voltammogram (CV) shows two cathodic peaks (P(C1) and P(C2)) at -0.76 and -0.97 V and an anodic peak (P(A)) at -0.8 V, while two ECL peaks around -0.76 V are observed. Similar mechanisms of both ECLs are supposed and possibly related to the capture of an electron at a surface trap, that is, the surface sulfide vacancy (V(S)(2+)) of CdS nanotubes and its electrocatalytic reduction to H(2)O(2) generated from the dissolved oxygen. P(C2) and P(A) are ascribed to the two-electron redox at V(S)(2+). Moreover, electrocatalysis to nitrate reduction is also found at P(C2), with a good linear relationship between nitrate concentration and electrocatalytic peak current in CV.