Evaluation of the pulmonary toxicity of PSNPs using a Transwell-based normal human bronchial epithelial cell culture system.

To reduce the nanoplastics (NPs) toxicity assessment error, we established a Transwell-based bronchial epithelial cell exposure system to assess the pulmonary toxicity of polystyrene NPs (PSNPs). Transwell exposure system was more sensitive than submerged culture for toxicity detection of PSNPs. PSNPs adhered to the BEAS-2B cell surface, were ingested by the cell, and accumulated in the cytoplasm. PSNPs induced oxidative stress and inhibited cell growth through apoptosis and autophagy. A noncytotoxic dose of PSNPs (1 ng/cm2) increased the expression levels of inflammatory factors (ROCK-1, NF-κB, NLRP3, ICAM-1, etc) in BEAS-2B cells, whereas a cytotoxic dose (1000 ng/cm2) induced apoptosis and autophagy, which might inhibit the activation of ROCK-1 and contribute to reducing inflammation. In addition, the noncytotoxic dose increased the expression levels of zonula occludens-2 (ZO-2) and α1-antitrypsin (α-AT) proteins in BEAS-2B cells. Therefore, in response to PSNP exposure, a compensatory increase in the activities of inflammatory factors, ZO-2, and α-AT may be triggered at low doses as a mechanism to preserve the survival of BEAS-2B cells. In contrast, exposure to a high dose of PSNPs elicits a noncompensatory response in BEAS-2B cells. Overall, these findings suggest that PSNPs may be harmful to human pulmonary health even at an ultralow concentration.

Synchronized and asynchronous modulation of seismicity by hydrological loading: A case study in Taiwan.

Delineation of physical factors that contribute to earthquake triggering is a challenging issue in seismology. We analyze hydrological modulation of seismicity in Taiwan using groundwater level data and GNSS time series. In western Taiwan, the seismicity rate reaches peak levels in February to April and drops to its lowest values in July to September, exhibiting a direct correlation with annual water unloading. The elastic hydrological load cycle may be the primary driving mechanism for the observed synchronized modulation of earthquakes, as also evidenced by deep earthquakes in eastern Taiwan. However, shallow earthquakes in eastern Taiwan (<18 km) are anticorrelated with water unloading, which is not well explained by either hydrological loading, fluid transport, or pore pressure changes and suggests other time-dependent processes. The moderate correlation between stacked monthly trends of large historic earthquakes and present-day seismicity implies a modestly higher seismic hazard during the time of low annual hydrological loading.

Synthesis and evaluation of a new fluorescent transglycosylase substrate: lipid II-based molecule possessing a dansyl-C20 polyprenyl moiety.

The preparation of a novel fluorescent lipid II-based substrate for transglycosylases (TGases) is described. This substrate has characteristic structural features including a shorter lipid chain, a fluorophore tag at the end of the lipid chain rather than on the peptide chain, and no labeling with a radioactive atom. This fluorescent substrate is readily utilized in TGase activity assays to characterize TGases and also to evaluate the activities of TGase inhibitors.

The hepatoprotective effects of Limonium sinense against carbon tetrachloride and beta-D-galactosamine intoxication in rats.

In the present study, the hepatoprotective action of Limonium sinense (Plumbaginaceae) was evident after carbon tetrachloride (CCl(4)) and beta-D-galactosamine (D-GalN), respectively, challenge in rats. The plant materials were divided into two parts: (1) the roots extracted with water (WRE) and (2) the leaves extracted with methanol and fractionated with chloroform (CLE). Both WRE and CLE were extremely flavonoid-enriched extracts. In an CCl(4)-induced acute liver damage study, pretreatment with WRE at 300 mg/kg i.p. and CLE at 100 mg/kg i.p. significantly reduced the amino-transaminases levels of SGOT (p < 0.01) and SGPT (p < 0.01) previously increased by CCl(4) intoxication. In D-GalN-induced acute liver damage study, administration of WRE (300 and 500 mg/kg) or CLE (100 mg/kg) p.o. also significantly reduced the SGOT (p < 0.01) and SGPT (p < 0.01) levels previously increased by D-GalN intoxication. Furthermore, the serum triglyceride level was increased after pretreatment with WRE or CLE previously reduced by D-GalN intoxication. All of the liver function profiles were confirmed to have improvement of liver lesion in histopathological observation. In an acute toxicity test on ICR mice, the LD(50) of WRE was 777.6 mg/kg i.p. An in vitro study showed that CLE possessed a more potent cytotoxicity to human hepatocellular carcinoma cells (Hep3B) (EC(50) = 43.1 micro g/mL) than the other organic fractions, which were fractionated from methanol extracts of the leaves of L. sinense. The present results conclude that L. sinense possesses a hepatoprotective efficacy, and is relatively safe in rats.

Anti-inflammatory and hepatoprotective activity of peh-hue-juwa-chi-cao in male rats.

Peh-hue-juwa-chi-cao (PHJCC) is a common commercial name for the herbal extract of either Hedyotis diffusa (HD), H. corymbosa (HC), or Mollugo pentaphylla (MP). The present study was carried out to investigate the anti-inflammatory and hepatoprotective effects of these three extracts in rats. The results indicated that extracts of HC, HD and MP possess anti-inflammatory activity, and that MP has the greatest inhibition against carrageenan-induced paw edema. In the hepatoprotective study, results indicated that the three plant extracts significantly reduced the acute elevation of serum glutamate oxalate transaminase (sGOT) and serum glutamate pyruvate transaminase (sGPT) concentration, and alleviated the degree of liver damage 24 hours after the intraperitoneal administration of hepatotoxins.