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In recent years, related research has mainly examined lipophilic marine toxins (LMTs) in contaminated bivalves or toxic algae, whereas the levels of LMTs in seawater remain largely unexplored. Okadaic acid (OA), yessotoxin (YTX), and pectenotoxin-2 (PTX2) are three typical LMTs produced by certain marine algae that are closely linked to diarrhetic shellfish poisoning. In this study, a new method of solid phase extraction combined with liquid chromatography - electrospray ionization ion trap tandem mass spectrometry was developed to determine the presence of OA, YTX, and PTX2 in seawater simultaneously. Satisfactory sensitivity, repeatability (RSD < 25.00%) and recovery (56.25-70.18%) of the method were achieved. Then, the method was applied to determine the amounts of the three toxins in the coastal seawater. OA and PTX2 were detected in all the seawater samples collected from eight locations along the coastline of Qingdao City, China on October 23, 2012, with concentration ranges of OA 4.24-9.64 ng L-1 and PTX2 0.42-0.74 ng L-1. Monthly concentrations of OA and PTX2 in the seawater of four locations were determined over the course of a year, with concentration ranges of OA 1.41-89.52 ng L-1 and PTX2 below detectable limit to 1.70 ng L-1. The peak values of OA and PTX2 in coastal seawater were observed in August and July, respectively. Our results suggest that follow-up research on the fate modeling and risk assessment of LMTs in coastal seawater should be implemented. [ABSTRACT FROM AUTHOR]

Tenacissoside H (TEH), which has anti-inflammatory and anti-tumor effects, is a major active ingredient extracted from the stem of Marsdenia tenacissima. However, the effect of TEH on hepatocellular carcinoma (HCC) as well as the underlying mechanisms are still indistinct. Presently, HCC cells (including Huh-7 and HepG2) were dealt with different concentrations of TEH. The proliferation and apoptosis of HCC cells were determined via Cell Counting Kit-8 (CCK8) assay and flow cytometry. In addition, Western blot was conducted to evaluate the expressions of autophagy--and apoptosis-related proteins. Tissue immunofluorescence was carried out to evaluate LC3B expression in the tumor tissues. The data showed that TEH suppressed the growth of HCC cells in a concentration-dependent manner. Besides, TEH enhanced radiosensitivity and promoted the apoptosis of HCC cells. Moreover, the mRNA and protein levels of autophagy-related genes (LC3-II/LC2-I, ATG5, Beclin-1) were significantly promoted by TEH. Mechanistically, TEH attenuated the activation of PI3K/Akt/mTOR signaling pathway. However, inhibition of PI3 K pathway abolished the anti-tumor effects of TEH in HCC cells. Collectively, this study suggested that TEH increases the radiosensitivity of HCC cells via inducing autophagy and apoptosis through downregulating PI3K/Akt/mTOR signaling pathway. [ABSTRACT FROM AUTHOR]

Objective: To investigate the efficacy of tilianin extracted from Xiangqinglan () on apoptosis of H9c2 cell after oxygen-glucose deprivation/reoxygenation (OGD/R) and the mechanism., Methods: Tilianin was obtained from Beijing Inluck Science and Technology Development Co. Ltd., with purity ≥ 98%. The OGD/R model was established in H9c2 cells. Flow cytometry detected the mitochondrial membrane potential, apoptosis rates, mitochondrial reactive oxygen species (ROS) and calcium ion concentration. Succinate dehydrogenase (SDH) activity, succinate content and levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and interleukin-1 β (IL-1β) were detected with enzyme-linked immunosorbent assay. Western blot measured protein levels., Results: Tilianin significantly reduced the apoptotic rates, ROS levels, calcium ion concentration, succinate content, and, levels of TNF-α, IL-6 and IL-1β of OGD/R cells, while significantly increased the membrane potential and SDH activity in mitochondria. Western blot analysis showed that tilianin significantly up-regulated p-Calmodulin-dependent protein kinase Ⅱ and voltage-dependent anion selective channel levels in OGD/R cells, while significantly down-regulated p-protein kinase B, Bcl-2-associated X, and dynamin-related protein 1 levels related to apoptosis in the mitochondrial pathway. Moreover, tilianin significantly up-regulated B-cell lymphoma-2 and mitochondrial protein 2 related to the inhibition of apoptosis. Furthermore, tilianin down-regulated phosphorylated-apoptosis signal-regulated kinase 1, phosphorylated-p38 and C/EBP homologous protein related to endoplasmic reticulum stress., Conclusions: Tilianin may inhibit OGD/R-induced H9c2 cell apoptosis mediated by mitochondrial pathway and endoplasmic reticulum stress, thus protecting cardiomyocytes.

Aims: To analyze the changes of CD4+ T-cell subsets following radiofrequency ablation (RFA) in lung cancer and the impact of RFA on the antitumor immunity., Subjects and Methods: Flow cytometry was employed to detect CD4+ T-cell subsets in the peripheral blood from 45 healthy controls and 45 lung cancer patients before and after RFA. The correlation between CD4+ T-cell subsets and the clinical characteristics was discussed by comparing the results between different groups., Results: Compared with the healthy controls, the lung cancer patients showed a decline in Th1 cells, but higher Th2, Th17, and Treg cells (P < 0.05). Th1 cell level and Th1/Th2 cell ratio were significantly lower for stage III/IV than Stage I/II and also lower for patients with Karnofsky Performance Status (KPS) score <60 than ≥ 60 (P < 0.05). The levels of Th2, Th17, and Treg cells were much higher for patients with Stage III/IV and KPS score <60 (P < 0.05). After 2 weeks of RFA, the level of Th1 cells and Th1/Th2 cell ratio increased, while the levels of Th2, Th17, and Treg cells declined (P < 0.05). For lesions with ablation volume ≥ 70%, the level of Th1 cells and Th1/Th2 cell ratio increased, whereas the levels of Th2, Th17, and Treg cells declined dramatically (P < 0.05)., Conclusions: The level of Th1 cells declined in lung cancer patients, especially for patients with Stage III/IV and KPS score <60. After RFA, the level of Th1 cells and Th1/Th2 increased, whereas the levels of Th2, Th17, and Treg cells declined, indicating an improvement of antitumor immunity. The changes were more prominent for lesions with ablation volume ≥ 70%.

Metal nanoparticles (MNps) tend to be influenced by environmental factors such as pH, ionic strength, and temperature, thereby leading to aggregation. Forming stable aqueous dispersions could be one way of addressing the environmental toxicity of MNps. In contrast to the electrolyte-induced aggregation of MNps, novel zwitterionic sulfabetaine polymers reported here act as stabilizers of MNps even under high salinity. Polysulfabetaines exhibited unique solubility and swelling tendencies in brine and deionized water, respectively. The polysulfabetaines derived from methacrylate (PSBMA) and methacrylamide (PSBMAm) also showed reversible salt-responsive and thermoresponsive behaviors as confirmed by cloud-point titration, transmittance, and dynamic light scattering studies. The brine soluble nature was explored for its ability to be used as a capping agents to form metal nanoparticles using formic acid as a reducing agent. Thus, silver and noble metal (gold and palladium) nanoparticles were synthesized. The nanoparticles formed were characterized by UV-vis, XRD, TEM, EDX, and DLS studies. The size of the nanoparticles remained more or less the same even after 2 months of storage in 2 M sodium chloride solution under ambient conditions and also at elevated temperatures as confirmed by light-scattering measurements. The tunable, stimuli-responsive polysulfabetaine-capped stable MNp formed under low (hyposalinity) and hypersalinity could find potential applications in a variety of areas.