基于灰色关联度分析和聚类分析的3种滇产重楼抗肝癌作用谱效关系探索

目的:研究长柱重楼、滇重楼和南重楼的HPLC指纹图谱与其抗肝癌作用的谱效关系,为明确重楼抗肝癌作用的物质基础提供实验依据。方法:采用HPLC建立3种重楼提取物的指纹图谱,流动相乙腈(A)-水(B)梯度洗脱(0～10 min,20%A; 10～20 min,20%～25%A; 20～30 min,25%～30%A; 30～40 min,30%～35%A; 40～50 min,35%～40%A; 50～60 min,40%A; 60～75 min,40%～45%A; 75～80 min,45%～60%A),流速0. 9 m L·min~(-1),检测波长203 nm;利用噻唑蓝(MTT)比色法测定3种重楼提取物对肝癌HepG2细胞的增殖抑制作用,计算半数抑制浓度(IC_(50));运用聚类分析(HCA)和灰色关联度分析(GRA)研究3种重楼指纹图谱和抗肝癌作用的关系,找出对抗肝癌作用贡献较大的成分。结果:在3种重楼的HPLC指纹图谱中,确定其中11个色谱峰为共有峰。作用时间72 h时长柱重楼、滇重楼、南重楼的IC_(50)分别为148. 33,178. 87,208. 09 mg·L~(-1),其中长柱重楼的抗肝癌活性最强。灰色关联度结果显示,滇重楼共有峰中关联度较高的为1～10号峰,长柱重楼共有峰关联度较高的为1～7号峰,南重楼共有峰中关联度较高的为1～4,6～10,N1号峰,与IC_(50)关联度均0. 7。各重楼变量的聚类分析结果显示,可与IC_(50)聚为一类的色谱峰的关联度均 0. 7。结论:建立了3种重楼的HPLC指纹图谱,重复性良好。3种重楼中的1～4,6和7号色谱峰对抗肝癌药效贡献最大。     

Evaluating the inhibitory potential of Withania somnifera on platelet aggregation and inflammation enzymes: An in vitro and in silico study

Context Withania somnifera (L.) Dunal is traditionally used for treating various ailments, but lacks scientific evaluation.

Objective This study evaluates Withania somnifera (WS) for its effect on platelet activity and inflammatory enzymes.

Materials and methods Aqueous and ethanolic (1:1) leaf extracts were subjected to in vitro indirect haemolytic activity using Naja naja venom, human platelet aggregation was quantified for lipid peroxidation using arachidonic acid (AA) as agonist and 5-lipoxygenase (5-LOX) levels were determined using standard spectrometric assays. Further, molecular docking was performed by the ligand fit method using molegro software package (Molegro ApS, Aarhus, Denmark).

Results The study found that aqueous and ethanol extracts have very negligible effect (15%) with an IC₅₀ value of 13.8?mg/mL on PLA₂ from Naja naja venom. Further, extracts of WS also had very little effect (18%) with an IC₅₀ value of 16.6?mg/mL on malondialdehyde (MDA) formation. However, a 65% inhibition of 5-LOX with an IC₅₀ value of 0.92?mg/mL was observed in 1:1 ethanol extracts. The same was evident from SAR model with the active ingredient withaferin A binding predominantly on Phe 77, Tyr 98, Arg 99, Asp 164, Leu 168, Ser 382, Arg 395, Tyr 396 and Tyr 614 with an atomic contact energy value of??128.96 compared to standard phenidone (?103.61). Thus, the current study validates the application of WS for inflammatory diseases.

Conclusion This study reveals the inhibitory potential of W. somnifera on inflammatory enzymes and platelet aggregation. Thus, WS can serve as a newer, safer and affordable medicine for inflammatory diseases.     

直丝弓矫治器和Begg矫治器治疗安氏Ⅱ类1分类错[牙合]畸形疗效比较

目的:对比不同矫治器对错[牙合]畸形患者面高度及前后牙咬合关系的影响。方法:选取于笔者医院接受矫治的83例错[牙合]畸形患者,根据患者矫治器类型分为直丝弓组和Begg组,分别为42例和41例。比较并分析两组患者治疗前后牙咬合关系、硬组织、磨牙及面高度的变化情况。结果:矫治后,两组患者OJ-PPV、OB-PP、LMA-MPV、LMA-MPV均降低,Begg矫治组OJ-PPV水平显著高于直丝弓矫治组,OB-PP、LMA-MPV、LMA-MPV水平显著低于直丝弓矫治组,差异均具有统计学意义(P<0.05);两组患者LAFH、LAFH/TAFH、PFH/TAFH水平均升高,其中Begg矫治组患者LAFH水平显著低于直丝弓矫治组,差异均具有统计学意义(P<0.05);两组患者LMA-MP、LMC-MP水平均升高,差异具有统计学意义(P<0.05);矫治前后,两组患者SNA、SNA、ANB水平均无统计学差异(P>0.05)。结论:两种矫治器对错[牙合]畸形患者硬组织变化均无明显影响,其中Begg矫治对患者前后牙咬合关系改善作用更强,直丝弓对患者面高度的改善能力更强。     

Niven and Scott (2003): Sixteen years of hindsight

This paper revisits a 2003 publication in Nursing Philosophy: The need for accurate perception and informed judgement in determining the appropriate use of the nursing resource: hearing the patient's voice. The author suggests that the basic ideas and focus of this 16‐year‐old paper are still topical and relevant in considerations of nursing care. However, it is also suggested that greater attention to the importance of the nurse–patient relationship in considerations of resource allocation, and potential rationing of nursing care, would have strengthened the original paper.     

基于“通肾络、益脾肾”治法研究足细胞凋亡及自噬

[目的]基于中医"通肾络、益脾肾"治法,探讨通络益肾方对体外高糖培养的小鼠肾小球足细胞自噬和凋亡蛋白SIRT1、BNIP3、P62、Bax表达的调控影响。[方法]成熟无特定病原体(SPF)级SD雄性大鼠40只,随机分为正常组、中药高、中、低剂量组各10只。按照人与大鼠体表面积折算方法计算出大鼠所需中药灌胃浓度:高剂量浓度4.76 g/mL、中剂量浓度2.38 g/mL、低剂量浓度1.19 g/m L,灌胃10 d取含药血清备用。足细胞分6组,正常组5.6 mmol/L葡萄糖+10%正常大鼠血清、高糖组30mmol/L葡萄糖+10%正常大鼠血清、通络益肾方含药血清高、中、低干预组30 mmol/L葡萄糖+10%高、中、低剂量大鼠血清、高渗组甘露醇24.5 mmol/L+10%正常大鼠血清。细胞培养48 h后收集,Hoechst33342荧光染色,观察各组足细胞凋亡状况及形态变化;流式细胞仪检测足细胞凋亡率;Western Blot检测细胞内自噬标志蛋白SIRT1、P62及促凋亡蛋白BNIP3、Bax表达水平。[结果]流式细胞仪检测结果显示通络益肾方中、低剂量组可降低高糖诱导的足细胞凋亡率(P0.01或P0.05),高剂量组不能改善凋亡情况(P0.05);Hoechst33342荧光染色观察结果也证实通络益肾方中、低剂量组可降低高糖诱导的足细胞凋亡率;蛋白印迹结果显示,与高糖组相比,通络益肾方中、低剂量组自噬标志蛋白SIRT1表达升高,自噬标志蛋白P62及促凋亡蛋白BNIP3、Bax蛋白表达下降(P0.05或P0.01),高剂量组SIRT1、BNIP3、P62、Bax蛋白表达未见明显改变(P0.05)。[结论]中剂量、低剂量通络益肾方能够启动细胞自噬减少高糖刺激下体外培养足细胞凋亡,降低细胞凋亡率及凋亡蛋白的表达。     

Derivation of internal dose-based thresholds of toxicological concern for occupational inhalation exposure to systemically acting organic chemicals

This study aimed at deriving occupational thresholds of toxicological concern for inhalation exposure to systemically-acting organic chemicals using predicted internal doses. The latter were also used to evaluate the quantitative relationship between occupational exposure limit and internal dose. Three internal dose measures were identified for investigation: (i) the daily area under the venous blood concentration vs. time curve, (ii) the daily rate of the amount of parent chemical metabolized, and (iii) the maximum venous blood concentration at the end of an 8-hr work shift. A dataset of 276 organic chemicals with 8-hr threshold limit values-time-weighted average was compiled along with their molecular structure and Cramer classes (Class I: low toxicity, Class II: intermediate toxicity, Class III: suggestive of significant toxicity). Using a human physiologically-based pharmacokinetic model, the three identified dose metrics were predicted for an 8-hr occupational inhalation exposure to the threshold limit value for each chemical. Distributional analyses of the predicted dose metrics were performed to identify the percentile values corresponding to the occupational thresholds of toxicological concern. Also, simple linear regression analyses were performed to evaluate the relationship between the 8-hr threshold limit value and each of the predicted dose metrics, respectively. No threshold of toxicological concern could be derived for class II due to few chemicals. Based on the daily rate of the amount of parent chemical metabolized, the proposed internal dose-based occupational thresholds of toxicological concern were 5.61?×?10^?2 and 9?×?10^?4 mmol/d at the 10th percentile level for classes I and III, respectively, while they were 4.55?×?10^?1 and 8.5?×?10^?3 mmol/d at the 25th percentile level. Even though high and significant correlations were observed between the 8-hr threshold limit values and the predicted dose metrics, the one with the rate of the amount of chemical metabolized was remarkable regardless of the Cramer class (r² = 0.81; n = 276). The proposed internal dose-based occupational thresholds of toxicological concern are potentially useful for screening-level assessments as well as prioritization within an integrated occupational risk assessment framework.     

Chalcone hybrids and their antimalarial activity

Malaria, one of the most striking, re-emerging infectious diseases caused by the genus Plasmodium, places a huge burden on global healthcare systems. A major challenge in the control and eradication of malaria is the continuous emergence of increasingly widespread drug-resistant malaria, creating an urgent need to develop novel antimalarial agents. Chalcone derivatives are ubiquitous in nature and have become indispensable units in medicinal chemistry applications due to their diverse biological profiles. Many chalcone derivatives demonstrate potential in vitro and in vivo antimalarial activity, so chalcone could be a useful template for the development of novel antimalarial agents. This review covers the recent development of chalcone hybrids as antimalarial agents. The critical aspects of the design and structure–activity relationship of these compounds are also discussed.     

Understanding the Influence of Nanocarrier-Mediated Brain Delivery on Therapeutic Performance Through Pharmacokinetic-Pharmacodynamic Modeling

This study aimed at evaluating how encapsulation in a regular nanocarrier (NC) (providing extended circulation time) or in a brain-targeting NC (providing prolonged circulation time and increased brain uptake) may influence the therapeutic index compared with the unformulated drug and to explore the key parameters affecting therapeutic performance using a model-based approach. Pharmacokinetic (PK) models were built with chosen PK parameters. For a scenario where central effect depends on area under the unbound brain concentration curve and peripheral toxicity relates to peak unbound plasma concentration, dose-effect and drug-side effect curves were constructed, and the therapeutic index was evaluated. Regular NC improved the therapeutic index compared with the unformulated drug due to reduced peripheral toxicity, while brain-targeting NC enhanced the therapeutic index by lowering peripheral toxicity and increasing central effect. Decreasing drug release rate or systemic clearance of NC with drug still encapsulated could increase the therapeutic index. Also, a drug with shorter half-life would therapeutically benefit more from a NC encapsulation. This work provides insights into how a NC for brain delivery should be optimized to maximize the therapeutic performance and is helpful to predict if and to what extent a drug with certain PK properties would obtain therapeutic benefit from nanoencapsulation.