A bromine-catalysis-synthesized poly(3,4-ethylenedioxythiophene)/graphitic carbon nitride electrochemical sensor for heavy metal ion determination

In this paper, poly(3,4-ethylenedioxythiophene)/graphitic carbon nitride (PEDOT/g-C₃N₄) composites were prepared by the bromine catalysed polymerization (BCP) method with varying weight ratios of monomer to g-C₃N₄. For comparison, solid-state polymerization (SSP) and metal oxidative polymerization (MOP) methods were also used for the synthesis of PEDOT/g-C₃N₄ composites. Electrochemical determination of heavy metal ions (Cd²⁺ and Pb²⁺) was carried out by differential pulse voltammetry (DPV) on composite-modified glass carbon electrodes (GCEs), which were prepared by different methods. The obtained composites were analysed by Fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible absorption spectroscopy (UV-vis), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results showed that the bromine catalysed polymerization (BCP) method is an effective way to prepare the PEDOT/g-C₃N₄ composite, and the combination of PEDOT with g-C₃N₄ can improve the electrochemical activity of electrode materials. And, the composite from the BCP method modified electrode (PEDOT/10 wt% g-C₃N₄/GCE) exhibited the widest linear responses for Cd²⁺ and Pb²⁺, ranging from 0.06–12 μM and 0.04–11.6 μM with detection limits (S/N = 3) of 0.0014 μM and 0.00421 μM, respectively.

The PEDOT/g-C₃N₄ composite prepared by a Br₂-catalyzed polymerization method exhibited the widest linear electrochemical responses for Cd²⁺ and Pb²⁺.     

兴趣在大学生学习中的作用与培养

在大学教学和学习中,学习兴趣是引导学生追求知识的最关键非智力因素之一,兴趣在目前的教育教学中受到越来越多的重视。本文主要论述了兴趣在大学生学习生活中的作用、个人应如何对待自身的兴趣以及作为教育工作者该如何引导和培养学生的学习兴趣,从而改善学习效果。     

PSA-NCAM is up-regulated during optic nerve regeneration in lizard but not in goldfish

The addition of polysialic acid (PSA) to neural cell adhesion molecule (NCAM) facilitates axon growth. Here we use Western blots and immunohistochemistry to examine expression of PSA-NCAM during optic nerve regeneration. In lizard, retinal ganglion cell axons become transiently PSA-NCAM positive. By contrast, goldfish RGC axons are PSA-NCAM negative both in normal animals and throughout regeneration with the exception of a PSA-NCAM-positive fascicle arising from newly generated RGCs. Transient sialylation of NCAM in lizard may assist regeneration in the nonpermissive reptilian visual pathway and facilitate the reestablishment of a crude topographic map; down-regulation in the long term may contribute to the breakdown in topography. The lack of sialylation in goldfish presumably reflects the permissive nature of the substrate allowing axon regeneration and the successful reestablishment of a topographic map.     

骨髓基质细胞的体外培养和分化诱导

目的 :建立一种简单可靠的骨髓基质细胞 (BMSc)向成骨细胞转化的体外培养方法 ,探讨骨髓基质细胞向成骨细胞转化的机理。 方法:将兔 BMSc悬液进行体外培养 ,进行形态学观察和组织学检测。 结果:传代培养细胞的碱性磷酸酶 (AL P)阳性率达 80 %以上 ,表现为成骨细胞形态并形成钙结节。结论:地塞米松、β-甘油磷酸钠和维生素 C可促进 BMSc分化为成骨细胞 ,BMSc的分化和增殖是两个对立的状态。     

髂腹股沟带蒂真皮下血管网皮瓣的解剖及临床应用

目的:观察带血管蒂的髂腹股沟真皮下血管网皮瓣的解剖及临床疗效。方法 :经股动脉灌注红色乳胶于 10例 2 0侧尸体标本内 ,对髂腹股沟真皮下血管网皮瓣血供进行解剖及观察 ,修复手腕部及前臂部软组织缺损2 4例。 结果:髂腹股沟真皮下血管网皮瓣的血供来自旋髂浅动脉 ,并在髂前上棘外 (2± 0 .4 ) cm处出浅筋膜进入真皮下 ,供应最大面积为 9cm× 2 0 cm ,全部存活且功能及色泽较好。结论 :带血管蒂的髂腹股沟真皮下血管网皮瓣是修复手部软组织缺损的理想供区     

β-环糊精包结祖卡木颗粒中挥发油实验研究

目的优选出β-环糊精(β-CD)包结祖卡木颗粒中挥发油的最佳工艺。方法以挥发油利用率为指标,采用饱和水溶液法和L9(34)正交设计表安排实验,对3个因素进行考察。结果挥发油和β-CD(mL/g)的比例为0.7∶4、包合温度为20℃、包合时间为30min时挥发油的包合率最佳。结论该方法操作简便,挥发油利用率高,有利于拓宽孜然油的应用。     

A review of the medicinal uses,phytochemistry and pharmacology of the genus Sapium

Ethnopharmacological relevance

Several species from the genus Sapium possess a broad range of medicinal properties and they have been used as traditional medicines by indigenous groups in several regions such as Malaysia, Africa, Southern China and Bolivia. Most of the species reported to possess therapeutic effects which are used for the treatment of skin-related diseases such as eczema and dermatitis, but they may also be used for overstrain, lumbago, constipation and hernia. Species of this genus are also used to treat wounds and snake bites. In addition, the saps/latex of Sapium glandulosum, Sapium indicum and Sapium sebiferum have/has toxic effects and are used as bird and fish poisons. This review discusses the current knowledge of the medicinal uses, phytochemistry, biological activities and toxicities of species from the genus Sapium to reveal their therapeutic potentials and gaps offering opportunities for future research.

Materials and methods

This review is based on a literature study of scientific journals and books from libraries and electronic sources, such as ScienceDirect, PubMed and ACS.

Results

As many as 65 compounds are included in this review. They belong to different classes of compounds including flavonoids, terpenoids and several other types of compounds, such as alkaloids, phenolic acids and amides. The pharmacological studies revealed that various types of preparations, extracts and single compounds of species from this genus exhibited a broad spectrum of biological activities including antioxidant, antimicrobial, anti-inflammatory and cytotoxic activities. However, Sapium glandulosum, Sapium indicum and Sapium sebiferum were reported to possess toxic effects and Sapium sebiferum was found to contain phorbol esters acting as a tumor-promoting agent.

Conclusion

The genus Sapium consists of 23 accepted (high confidence) species. However, only very few of species have been phytochemically and pharmacologically studied. There is great potential to discover new chemical constituents from this genus because only a few species have been phytochemically investigated thus far. Only 27 compounds of 65 identified compounds have been studied for their biological activities. Several extracts and single compounds from this genus were reported to exhibit interesting biological activities such as antimicrobial, antioxidant and cytotoxic effects. Furthermore, the toxicity studies of some phorbol esters suggested that the compounds acted as potential tumor-promoting agents by stimulating protein kinase C. This is an interesting fact in which a plant with medicinal properties also possesses toxic effects as well. Therefore, more clinical studies on the toxicity of the extracts of the plants and the compounds isolated from this genus are also crucial to ensure their safety and to assess their eligibility for use as sources for modern medicines.     

野山杏果肉的保肝作用及其对高脂血症小鼠血脂的影响

探讨野山杏果肉(FWA)的保肝作用和对高脂血症小鼠血脂的影响.方法选用♂昆明种小鼠,随机分为正常对照组、高脂模型组、血脂康阳性对照组以及FWA高、中、低剂量组,ig脂肪乳剂4周,建立小鼠高脂血症模型,同时ig0.1 g·kg-1·d-1血脂康和FWA(0.2、0.3、0.4g·kg-1·d-1).4周后,所有小鼠空腹过...     

Correlation analysis of riboflavin,RFT2 and Helicobater pylori in gastric carcinoma

Objective: To investigate the relationship between tissue riboflavin level and riboflavin transporter 2 (RFT2) protein expression, and the relationship between Helicobacter pylori (H.pylori) infection and the plasma riboflavin level in gastric carcinoma (GC). Methods: Enzyme-linked immunosorbent assay (ELISA) was used to detect tissue riboflavin level in patients with GC. Western blotting was applied to analyze the expression of RFT2 protein in 60 tissue samples from gastric carcinoma together with their normal tissues. The Warthin-starry method, rapid urease test and ¹⁴C-UBT were administered to detect the infection of H.pylori. High performance liquid chromatography (H.PYLORILC) was performed to detect plasma riboflavin level in the GC. Results: A significant decrease in the tissue riboflavin level was detected in GC samples compared to those in the normal mucous membrane (17.02±3.91 vs. 21.0±4.73; P = 0.043), and a significant decrease in the RFT2 protein was found in GC samples compared to those in the normal mucous membrane (0.92±0.39 vs. 1.23±0.51; P = 0.042). A positive correlation of tissue riboflavin level with defective expression of RFT2 protein was observed in GC patients (χ² = 1.969; P = 0.039). Plasma riboflavin level in gastric cancer without H.pylori infection group (1.6674 ng/mL ±0.37009 ng/mL) was higher than H.pylori infection group (1.2207 ng/mL ±0.17727 ng/mL, P = 0.043). Conclusion: The results indicate that RFT2 plays an important role in gastric carcinogenesis by modulating riboflavin absorption. H.pylori infection affects plasma riboflavin level and the prognosis of patients with gastric cancer.