Chi-square analysis of the reduction of ATP levels in L-02 hepatocytes by hexavalent chromium

Abstract

This study explored the reduction of adenosine triphosphate (ATP) levels in L-02 hepatocytes by hexavalent chromium (Cr(VI)) using chi-square analysis. Cells were treated with 2, 4, 8, 16, or 32 µM Cr(VI) for 12, 24, or 36 h. Methyl thiazolyl tetrazolium (MTT) experiments and measurements of intracellular ATP levels were performed by spectrophotometry or bioluminescence assays following Cr(VI) treatment. The chi-square test was used to determine the difference between cell survival rate and ATP levels. For the chi-square analysis, the results of the MTT or ATP experiments were transformed into a relative ratio with respect to the control (%). The relative ATP levels increased at 12 h, decreased at 24 h, and increased slightly again at 36 h following 4, 8, 16, 32 µM Cr(VI) treatment, corresponding to a “V-shaped” curve. Furthermore, the results of the chi-square analysis demonstrated a significant difference of the ATP level in the 32-µM Cr(VI) group (P < 0.05). The results suggest that the chi-square test can be applied to analyze the interference effects of Cr(VI) on ATP levels in L-02 hepatocytes. The decreased ATP levels at 24 h indicated disruption of mitochondrial energy metabolism and the slight increase of ATP levels at 36 h indicated partial recovery of mitochondrial function or activated glycolysis in L-02 hepatocytes.

Micropore‐Rich Carbon‐Confined Pt as the Phosphoric Acid Poisoning‐Resistant Electrocatalyst for Oxygen Reduction Reaction

“…[15,16] Meanwhile, Pt/MPC was synthesized as a contrast sample by depositing Pt-based NPs on the external surface of MPC derived from ZIF-8 through the ethylene glycol method. [17] The details could be found in the Experimental Section. Moreover, the synthesis of Pt@MPC was optimized by adjusting the dosage of Pt and polyvinylpyrrolidone (PVP).…”

“…Synthesis of Pt/MPC: 5.56 g of 2-methylimidazole and 2.97 g of Zn(NO 3 )•6H 2 O were dispersed in 120 mL of methanol and vigorously stirred for 24 h. Then, the sample was separated by centrifuging at 5000 rpm, washed and cleaned three times with methanol, followed by vacuum drying to obtain ZIF-8. MPC was obtained by heat treatment of ZIF-8 under N 2 atmosphere at 1000 °C for 2 h. According to the literature, [17] the H 2 PtCl 6 •6H 2 O was reduced to Pt NPs using the glycol method; then the Pt NPs were deposited on the MPC surface to obtain Pt/MPC.…”