Acute and chronic toxic effects of bisphenol a on Chlorella pyrenoidosa and Scenedesmus obliquus

The acute and chronic toxic effects of Bisphenol A (BPA) on Chlorella pyrenoidosa (C. pyrenoidosa) and Scenedesmus obliquus (S. obliquus) were not well understood. The indoor experiments were carried out to observe and analyze the BPA‐induced changes. Results of the observations showed that in acute tests BPA could significantly inhibit the growth of both algae, whereas chronic exposure hardly displayed similar trend. Superoxide dismutase (SOD) and Catalase (CAT) activities of both algae were promoted in all the treatments. Chlorophyll a synthesis of the two algae exhibited similar inhibitory trend in short‐term treatments, and in chronic tests C. pyrenoidosa hardly resulted in visible influence, whereas in contrast, dose‐dependent inhibitory effects of S. obliquus could be clearly observed. The experimental results indicated that the growth and Chlorophyll a syntheses of S.obliquus were more sensitive in response to BPA than that of C. pyrenoidosa, whereas for SOD andCAT activities, C. pyrenoidosa was more susceptible. This research provides a basic understanding of BPA toxicity to aquatic organisms. © 2012 Wiley Periodicals, Inc. Environ Toxicol 29: 714–722, 2014.     

Three new diphenylpropanes from Celastrus hindsii

Three new diphenylpropanes, Hindsiipropane A–C (1–3), together with one known arylpropyl quinone Griffithane D (4), were isolated from Celastrus hindsii. Their structures were established by 1D and 2D nuclear magnetic resonance spectroscopic analysis, and mass spectroscopy. Compound 4 was firstly obtained in this genus. All the isolated compounds were evaluated in vitro for cytotoxicity against four human tumor cell lines (A549, HCT116, MDA-MB-231, BEL7404) by the MTT assay.     

缬沙坦的合成工艺研究

目的研究缬沙坦的新合成方法。方法以N-(三苯基甲基)-5-(4'-溴甲基联苯-2-基)四氮唑为原料,经Kornblum氧化、还原胺化、酰化、去保护基制得N-[2'-(1H-四氮唑)-5-基]-[(1,1'-联苯-4-基)-甲基]-N-戊酰-L-缬氨酸甲酯,后经水解、酸化得缬沙坦。结果与结论目标化合物的结构经1H-NMR谱确证,总收率为37.6%。新方法避免了消旋化,为合成缬沙坦提供了新的思路。     

鼻咽癌中环氧化酶-2的实验研究

目的 研究环氧化酶-2在鼻咽癌中的表达,探讨其与鼻咽癌的增生、浸润及转移的关系。方法 在26例鼻咽癌及相应癌旁组织和10例正常鼻咽部黏膜组织中,应用逆转录-聚合酶链反应（RT-PCR）方法检测环氧化酶-2 mRNA的表达。结果 在鼻咽癌组织中环氧化酶-2 mRNA高表达,在正常鼻咽部黏膜环氧化酶-2 mRNA中低表达,差异具有统计学意义（P〈0.01）。结论 环氧化酶-2与鼻咽癌的生长、浸润及转移有密切关系。     

Three-channel capillary NF membrane with PAMAM-MWCNT-embedded inner polyamide skin layer for heavy metals removal

Nanofiltration (NF) membranes with simultaneous high rejection of divalent cations and anions and high water permeation were designed and fabricated via interfacial polymerization (IP) on three-channel capillary ultrafiltration (UF) membranes. MWCNTs-COOH were modified with poly(amidoamine) (PAMAM) and the as-synthesized MWCNTs-PAMAM were embedded into the inner polyamide skin-layer of the NF membranes by incorporating them into a piperazine (PIP) aqueous solution, followed by IP with trimesoyl chloride (TMC). The rigid MWCNTs and the dendrimer PAMAM molecules endow the as-fabricated NF membranes with high porosity and good hydrophilicity. Additionally, the –NH₂ groups of PAMAM introduce some positive sites into the polyamide layer. The as-prepared NF membranes with incorporated MWCNTs-PAMAM exhibit a pure water flux of 48.7 L m⁻² h⁻¹ and 92.6% and 88.5% rejection for Na₂SO₄ and MgCl₂, respectively, at 4 bar. Moreover, the NF membranes display high rejection for sulfates and metal cations, including heavy metal ions. The practicability of the membranes for mine-wastewater treatment was tested, and the membranes showed above 80% rejection of heavy metals and solution flux of about 30 L m⁻² h⁻¹. In addition, their separation performance and stability were satisfactory during the long-term run. The high rejection of the membranes for metal cations is ascribed to the positive sites offered by MWCNTs-PAMAM and the narrow membrane pores since both electrostatic repulsion and size exclusion play a role during membrane filtration. The good separation performance of the membranes for multivalent anions and heavy metal cations illustrates their potential for applications in heavy metal wastewater treatment.

MWCNTs-PAMAM were incorporated into the polyamide layer of NF membranes and the prepared membranes showed good permeation and rejection performances.     

Dimethyl Cardamonin Exhibits Anti-inflammatory Effects via Interfering with the PI3K-PDK1-PKCα Signaling Pathway

Consumption of herbal tea [flower buds of Cleistocalyx operculatus (Roxb.) Merr. et Perry (Myrtaceae)] is associated with health beneficial effects against multiple diseases including diabetes, asthma, and inflammatory bowel disease. Emerging evidences have reported that High mobility group box 1 (HMGB1) is considered as a key “late” proinflammatory factor by its unique secretion pattern in aforementioned diseases. Dimethyl cardamonin (2′,4′-dihydroxy-6′-methoxy-3′,5′-dimethylchalcone, DMC) is a major ingredient of C. operculatus flower buds. In this study, the anti-inflammatory effects of DMC and its underlying molecular mechanisms were investigated on lipopolysaccharide (LPS)-induced macrophages. DMC notably suppressed the mRNA expressions of TNF-α, IL-1β, IL-6, and HMGB1, and also markedly decreased their productions in a time- and dose-dependent manner. Intriguingly, DMC could notably reduce LPS-stimulated HMGB1 secretion and its nucleo-cytoplasmic translocation. Furthermore, DMC dose-dependently inhibited the activation of phosphatidylinositol 3-kinase (PI3K), phosphoinositide-dependent kinase 1 (PDK1), and protein kinase C alpha (PKCα). All these data demonstrated that DMC had anti-inflammatory effects through reducing both early (TNF-α, IL-1β, and IL-6) and late (HMGB1) cytokines expressions via interfering with the PI3K-PDK1-PKCα signaling pathway.     

Triazole-Linked Glycolipids Enhance the Susceptibility of MRSA to β-Lactam Antibiotics

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