Reducing dust using the electrocautery pencil with suction combined with the infusion catheter in mastectomy

The dust from the vaporized tissue released during a mastectomy presents a hazard to the patients and the operating room personnel. More dust has been noted using the conventional electrocautery pencil in dissecting breast tissue than with the metal knife used in the past. It is very important to reduce the hazardous dust released during mastectomy. For this study 80 patients undergoing mastectomy for breast cancer from March to June 2001 were divided into two groups: 1) those whose dissections were performed with a combination of an electrocautery pencil and suction with an intravenous infusion catheter (40 cases) and 2) those whose dissections were performed with the conventional method in which the electrocautery pencil was handled by the surgeon and the metal suction tube was used separately by an assistant (40 cases). During mastectomy the personal air sampler was affixed to the operator's neck to collect the dust from the vaporized tissue. The concentrations of the total dust were significantly lower in the combined electrocautery-suction method (mean 5.56 +/- 3.26 microg/m3) than in the conventional method (mean 34.81 +/- 4.83 microg/m3) during mastectomy (P < 0.05). Although the operating time and blood loss were less in the combined method than in the conventional method this difference was not statistically significant (P > 0.05). The combined method of using the electrocautery pencil for dissecting breast tissue along with the intravenous infusion catheter reduced the concentrations of the total dust from the vaporized tissue plume. Furthermore this method reduces the hazards of dust to the surgeons and operating room personnel. Additionally the cost of this combined method is lower than that of the conventional method.     

Interaction of green tea polyphenol epigallocatechin-3-gallate with sunitinib: potential risk of diminished sunitinib bioavailability

Sunitinib, a novel oral multi-targeted tyrosine kinase inhibitor for patients with metastatic renal cell carcinoma (mRCC) and advanced gastrointestinal stromal tumor, has a good prospect for clinical application and is being investigated for the potential therapy of other tumors. We observed the phenomenon that drinking tea interfered with symptom control in an mRCC patient treated with sunitinib and speculated that green tea or its components might interact with sunitinib. This study was performed to investigate whether epigallocatechin-3-gallate (EGCG), the major constituent of green tea, interacted with sunitinib. The interaction between EGCG and sunitinib was examined in vitro and in vivo. ¹H nuclear magnetic resonance (¹H-NMR) spectroscopy and mass spectrometry (MS) were used to analyze the interaction between these two molecules and whether a new compound was formed. Solutions of sunitinib and EGCG were intragastrically administered to rats to investigate whether the plasma concentrations of sunitinib were affected by EGCG. In this study, we noticed that a precipitate was formed when the solutions of sunitinib and EGCG were mixed under both neutral and acidic conditions. ¹H-NMR spectra indicated an interaction between EGCG and sunitinib, but no new compound was observed by MS. Sticky semisolid contents were found in the stomachs of sunitinib and EGCG co-administrated mice. The $ {\text{AUC}}_{{0 - \infty }} $ and C _max of plasma sunitinib were markedly reduced by co-administration of EGCG to rats. Our study firstly showed that EGCG interacted with sunitinib and reduced the bioavailability of sunitinib. This finding has significant practical implications for tea-drinking habit during sunitinib administration.     

Intestinal α-glucosidase inhibitory activity and toxicological evaluation of Nymphaea stellata flowers extract

Aim of the study

Nymphaea stellata willd. flowers (NSF) are used as a traditional medicine in India and Nepal to treat diabetic disease. Different works have demonstrated that NSF extract showed antihyperglycemic effect on alloxan-induced diabetic rats. In the present work we evaluated in vitro intestinal α-glucosidase inhibition as the possible mode of action of NSF extract on suppressing postprandial hyperglycemia for curing diabetic mellitus. In addition, NSF extract was studied to assess its possible acute oral toxicity and genotoxicity.

Materials and methods

Rat intestinal crude enzyme preparation and Caco-2 monolayer were used to evaluate α-glucosidase inhibitory activity of NSF extract. The main α-glucosidase inhibitors were detected by HPLC. For acute toxicity test, NSF extract was administered at doses of 2000, 5000 and 10,000 mg/kg body to three groups of 10 ICR mice each, and then clinical symptoms including mortality, clinical sign and gross findings were observed once a day for 14 days. In Ames test, histidine-dependent auxotrophic mutants of Salmonella typhimurium (strains TA97, TA98, TA100, TA102 and TA1535) were used and incubated in the presence and absence of S9 metabolic activation using NSF extract with concentrations of 150-5000 μg/plate. The chromosome aberration test was conducted with Chinese hamster lung (CHL) cells treated with NSF extract at doses of 150-5000 μg/ml in the presence and absence of S9 metabolic activation. In the in vivo mouse micronucleus assay, 9-week-old male and female ICR mice (n = 90, 25-30 g) were administered daily by oral gavage at doses of 2.5, 5.0 and 10.0 g/kg body for 1 or 2 days. Bone marrow smears were prepared from each treatment group 24 h after last administration and then polychromatic erythrocytes (PCEs) and normochromatic erythrocytes (NCEs) were identified.

Results

NSF extract showed potent rat intestinal α-glucosidase inhibitory activity for maltose hydrolysis with ED₅₀ value of 0.1 mg/ml. In Caco-2 monolayer, α-glucosidase activity for the maltose hydrolysis was down-regulated by NSF extract at a concentration of 0.05 mg/well level, showing 74% inhibition compared to the saline treated control. NSF was rich in phenol contents and the main α-glucosidase inhibitor, 1,2,3,4,6-penta-O-galloyl-β-d-glucose, was identified together with two phenolic compounds of gallic acid and corilagin. In acute toxicity test, NSF extract did not produce any toxic signs or deaths and the LD₅₀ value of this extract could be greater than 10,000 mg/kg body weight. These results of genotoxicity assessment showed that NSF extract did not cause genotoxic effects in Ames test, in the in vitro chromosomal aberration assay and in the in vivo micronucleus assay.

Conclusion

The current study shows that the extract from Nymphaea stellata flowers exhibits significant intestinal α-glucosidase inhibitory activity, without showing any acute toxicity or genotoxicity, which may be useful in suppressing postprandial hyperglycemia in diabetics. The results presented here suggest that the use of NSF in folk medicine as a natural antidiabetic treatment could be safe as well as beneficial.     

Current methods and research progress in nanomaterials risk assessment

Nanomaterials have unique physicochemical properties compared with those bulk materials of the same composition. Possible undesirable results of these capabilities are harmful interactions with biological systems and the environment, with the potential to generate toxicity. A number of studies on the effects of Nanomaterials in vitro and in vivo systems have been published. However, while the number of nanomaterials types and applications continues to increase, studies to characterize their effects after exposure and to address their potential toxicity are few in comparison, there is still a need for further studies that conclusively establish their safety/toxicity. The establishment of principles and test procedures to ensure safe manufacture and use of nanomaterials in the marketplace is urgently required and achievable. The major goal of this review is to summarize 1) analytical techniques applied for characterization of nanomaterials, 2) current analytical methods to assess nanomaterials toxicity in vitro and in vivo; 3) research progress of polymeric nanomaterials toxicity; 4) outlook.     

Expression of macrophage inflammatory protein-1α and monocyte chemoattractant protein-1 in glioma-infiltrating microglia: involvement of ATP and P2X₇ receptor

Chemokines can be produced by gliomas, which mediate the infiltration of microglia, a characteristic feature of glioma‐associated neuropathogenesis. ATP that is released at a high level from glioma has been reported to play a regulatory role in chemokine production in cultured glioma cells. The objective of this study was to define the potential role of extracellular ATP in the regulation of macrophage inflammatory protein‐1α (MIP‐1α) and monocyte chemoattractant protein‐1(MCP‐1) expression in glioma‐associated microglia/macrophages. The results showed that Iba1⁺ and ED1⁺ microglia existed in the tumor at 3 and 7 day after injection of C6 glioma cells into the rat cerebral cortex (dpi). ED1⁺ microglia/macrophages or Iba1⁺ microglia in the glioma were also colocalized to MIP‐1α‐ and MCP‐1‐expressing cells. In vitro study indicated that treatment with ATP and BzATP (an agonist for ATP ionotropic receptor P2X₇R) caused an increase in the intracellular levels of microglial MIP‐1α and MCP‐1. By using an extracellular Ca²⁺ chelator (EGTA) and P2X₇R antagonists, oxidized ATP (oxATP) and brilliant blue G (BBG), we demonstrated that BzATP‐induced production of MIP‐1α and MCP‐1 levels was due to P2X₇R activation and Ca²⁺‐dependent regulation. Coadministration of C6 glioma cells and oxATP into the rat cerebral cortex resulted in a reduction of MIP‐1α‐ and MCP‐1‐expressing microglia/macrophages. We suggest, based on the results from in vivo and in vitro studies, that a massive amount of ATP molecules released in the glioma tumor site may act as the regulator with P2X₇R signaling that increases MIP‐1α and MCP‐1 expression in tumor‐infiltrating microglia/macrophages. © 2010 Wiley‐Liss, Inc.     

儿童早期预警评分在识别危重患儿病情中的价值

目的 探讨儿童早期预警评分（PEWS）识别危重患儿病情的价值。方法 选取2016年1~12月由中南大学湘雅医院普通病区转入PICU或急诊收入PICU的患儿120例为PICU组,该院该期间入住普通病房的120例患儿作为对照组。对PICU组的120例患儿根据病种的不同分为呼吸/循环系统疾病亚组（55例）和神经/其他系统疾病亚组（65例）。记录患儿入院时的PEWS评分,采用受试者工作特征（ROC）曲线分析PEWS评分对病情评估的价值。结果 PICU组PEWS评分显著高于对照组（P < 0.05）。呼吸/循环系统疾病亚组的PEWS评分显著高于神经/其他系统疾病亚组（P < 0.05）。以患儿是否收住PICU为预测指标时,PEWS评分的最佳截断值为3.5分,灵敏度为85%,特异度为95%,ROC曲线下面积为0.951（95% CI：0.923~0.980）。其中神经/其他系统疾病亚组的患儿ROC曲线下面积为0.768,呼吸/循环系统疾病亚组的患儿ROC曲线下面积为0.968。PEWS评分 > 6分、4~6分及 ≤ 3分患儿的病死率分别为40%、21%、0,组间比较差异有统计学意义（P < 0.001）。结论 PEWS对识别危重症患儿病情严重程度有重要价值,且不同病种对PEWS评分的敏感性有差异;PEWS评分对患儿的预后有预测价值。     

乳源β-酪啡肽7对大鼠葡萄糖吸收的影响及其作用机制

目的: 探讨乳源活性肽β - 酪啡肽- 7 ( β -Casomorphin-7, β-CM7)应用于食品时对葡萄糖吸收的影响及其作用机制.方法: 选用健康成年SD大鼠, 分为对照组(0mol/L β-CM7), L低剂量组、M中剂量组、H高剂量组(终浓度分别为7.5×10-7, 7.5×10-6, 7.5×10-5 mol/L). 利用翻转离体小肠囊模型进行实验: (1)葡萄糖氧化酶法测定翻转后小肠内液葡萄糖含量;(2)比色法测定小肠黏膜Na+-K+-ATP酶活力;(3)荧光定量PCR法分析小肠黏膜组织中钠葡萄糖共转运载体(SGLT-1)和葡萄糖协助扩散转运载体(GLUT-2)mRNA的表达.结果: 在离体环境下β-CM7在7.5×10-7-7.5×10-5 mol/L浓度下对葡萄糖的吸收均有一定的抑制作用(1.09 mol/L, 1.24 mol/L, 1.12 mol/Lvs 1.74 mol/L, P = 0.01, 0.04, 0.02), 能够降低Na+-K+-ATP酶活力(85.73, 112.06, 109.68 vs114.93, P = 0.004, 0.73, 0.54);荧光定量PCR结果发现: 与对照组相比, β-CM7能够显著降低SGLT-1及GLUT-2 mRNA水平(0.46, 0.58, 0.77vs 1.11, P = 0.20, 0.05, 0.02;0.50, 0.66, 0.85 vs1.14, P = 0.30, 0.14, 0.03).结论: β-CM7可以通过降低Na+-K+-ATP酶活力及下调SGLT-1、GLUT-2 mRNA水平, 减少大鼠小肠对葡萄糖的吸收.     

二磷酸氯喹对K562细胞增殖与凋亡的影响

本研究探讨二磷酸氯喹对K562细胞增殖与凋亡的影响及其可能的作用机制。用细胞增殖试验（MTT法）检测不同浓度二磷酸氯喹对K562细胞的增殖抑制作用；应用细胞形态学检查、流式细胞术、DNA琼脂糖凝胶电泳观察和检测细胞凋亡；以罗丹明123（Rhodamine 123）为细胞染色剂，采用流式细胞术检测不同浓度二磷酸氯喹处理后K562细胞线粒体膜电位（△Ψm）的变化。结果表明：用不同浓度二磷酸氯喹（1.5625、3．125、6．25、12．5、25、50、100μmol／L）分别作用于K562细胞24、48和72小时后，细胞生长活力明显降低，具有剂量依赖性；典型的细胞形态学改变、亚G1峰的测出、梯形条带的显现共同证实了二磷酸氯喹能诱导K562白血病细胞凋亡；Rhodamine 123染色显示二磷酸氯喹处理的K562细胞线粒体膜电位强度下降。结论：二磷酸氯喹对K562细胞有生长抑制、诱导凋亡作用，其作用可能与细胞线粒体膜电位（△Ψm）下降有关。     

Pharmacophore modelling and virtual screening for identification of new Aurora-A kinase inhibitors

Aurora-A has been identified as one of the most attractive targets for cancer therapy and a considerable number of Aurora-A inhibitors have been reported recently. In order to clarify the essential structure-activity relationship for the known Aurora-A inhibitors as well as identify new lead compounds against Aurora-A, 3D pharmacophore models were developed based on the known inhibitors. The best hypothesis, Hypo1, was used to screen molecular structural databases, including Specs and China Natural Products Database for potential lead compounds. The hit compounds were subsequently subjected to filtering by Lipinski's rules and docking study to refine the retrieved hits and as a result to reduce the rate of false positive. Finally, 39 compounds were purchased for further in vitro assay against several human tumour cell lines including A549, MCF-7, HepG2 and PC-3, in which Aurora-A is overexpressed. Two compounds show very low micromolar inhibition potency against some of these tumour cells. And they have been selected for further investigation.