Identification of volatile organic compounds in muscle tissues of different species based on Headspace-Gas-Chromatography Ion-Mobility spectrometry

Species identification of unknown biological samples is crucial for forensic applications, especially in cases of explosion, disaster accidents, and body mutilation after murdering, as well as poaching, illegal trade in endangered animals, and meat food fraud. In this study, we identified 60 volatile organic compounds (VOCs) in fresh skeletal muscle tissues of seven different animal species (cattle, sheep, pigs, rabbits, rats, chickens and carp) and a human dead body by headspace-gas-chromatography ion-mobility spectrometry (HS-GC-IMS), and compared their differences by retention time, drift time and molecular weight. The results showed that these VOCs formed different gallery plot fingerprints in the skeletal muscle tissues of the human dead body and seven animal species. Principal component analysis (PCA) showed significantly different fingerprints between these species, and these fingerprints maintained good stability between the species and within the same species. Some VOCs have high species specificity, while VOCs of human fresh muscle tissues from different individual sources have little difference, demonstrating that all tested muscle tissue samples could be distinguished based on different VOCs. HS-GC-IMS has proved to be a rapid, high-throughput, highly sensitive and specific species identification method, which can be used for forensic species identification in criminal cases and disaster accidents, as well as detection in the field of food safety, such as meat fraud and adulteration.     

Biogenic silver,gold and copper nanoparticles - A sustainable green chemistry approach for cancer therapy

The advent of nanotechnology has revolutionized the way clinicians are treating cancers. Treatment for cancer includes surgery, radiotherapy, hormonal therapy, chemotherapy, and now nano therapy, which could be a possible alternative. This new treatment regime can be beneficial since it shows minimum side effects as compared to other treatment methods. Metallic nanoparticles synthesized through green chemistry by using biological entities minimizes the side effects and enhances the properties of the metal against cancer cells. These green nanoparticles are widely used in research and have shown promising cytotoxic activity against various cancer cell lines. Mechanistically, these nanoparticles can enter the cancer cell and cause cell death by the activation of various molecular pathways such as apoptosis, necrosis and autophagy. This review focuses on the metal nanoparticles (silver, gold and copper) synthesized by the green chemistry approach that have been utilized to study the cancer cell death and we are also discussing the underlying molecular pathways.     

经典名方物质基准研制的关键技术分析

中药经典名方开发已成为当下中医药界研究的热点之一,而其中经典名方物质基准的成功研制对于整个中药经典名方的申报极为关键。经典名方物质基准既是检测经典名方制剂质量的基准,同时又需反映整方的物质基础。中药成分众多而复杂,单成分的、化药式的研发与质量控制模式难以适用于整体药用的中药制剂的开发,亟需开辟一条中药专属的研发模式。以目前已有的现代科学技术,笔者建议将中药的遗传多态性、提取动力学、指纹图谱总量统计矩(相似度)法、超分子"印迹模板"等结合应用于经典名方物质基准的研制,探讨中药经典名方物质基准的质量控制技术,以期全面、准确地阐明药材-饮片-物质基准的成分群量值的传递规律,为推进中药经典名方的研制进程提供参考。     

翻转课堂教学法在天然药物化学实验中的应用

目的利用翻转课堂教学法改进传统的天然药物化学实验课教学模式,提高该课程的教学效果。方法从实验教学的课程设计与开发,课前自主学习、课中内化及课后评估和讨论等环节进行了一系列的探讨与改革。结果翻转课堂教学模式为解决学生长期以来在天然药物化学实验课中缺乏主动参与性、探索性等问题提供一剂良方。结论在天然药物化学实验课教学中引入翻转课堂教学模式的初步探索为天然药物化学实验课的改革提供了依据和思路。     

《医用有机化学》课程中进行德育渗透

教学与德育有机融会贯通,是当前教育领域的共识。医学本科生秉承"以德载医"的精神,肩负"治病救人"的重任,因此德育教育在整个医学教学中占有重要的地位。《医用有机化学》教材中含有丰富的德育内容,高校教师传授专业知识的同时,在教学过程中巧妙的穿插辩证唯物主义、爱国主义和社会责任感的思政教育,可以帮助学生们树立正确的世界观和人生观。文章以医用有机化学课程为例,主要从教师的自身道德素养、德育在教学过程中的具体实践和德育实施过程中需要注意的问题三方面进行阐述,充分将新时代新理念融入大纲、教案和课堂中,化"知识"为"智慧",变"文化"为"品格",充分发挥医用有机化学课程的德育功能。     

New Insight into the Fluorescence Quenching of Nitrogen-Containing Carbonaceous Quantum Dots—From Surface Chemistry to Biomedical Applications

Carbon-based quantum dots are widely suggested as fluorescent carriers of drugs, genes or other bioactive molecules. In this work, we thoroughly examine the easy-to-obtain, biocompatible, nitrogen-containing carbonaceous quantum dots (N-CQDs) with stable fluorescent properties that are resistant to wide-range pH changes. Moreover, we explain the mechanism of fluorescence quenching at extreme pH conditions. Our in vitro results indicate that N-CQDs penetrate the cell membrane; however, fluorescence intensity measured inside the cells was lower than expected from carbonaceous dots extracellular concentration decrease. We studied the mechanism of quenching and identified reduced form of β-nicotinamide adenine dinucleotide (NADH) as one of the intracellular quenchers. We proved it experimentally that the elucidated redox process triggers the efficient reduction of amide functionalities to non-fluorescent amines on carbonaceous dots surface. We determined the 5 nm–wide reactive redox zone around the N-CQD surface. The better understanding of fluorescence quenching will help to accurately quantify and dose the internalized carbonaceous quantum dots for biomedical applications.     

HSG、Ki67组织表达与宫颈癌新辅助化疗治疗效果的相关分析

目的探讨细胞增殖抑制基因(HSG)、增殖细胞核抗原(Ki67)组织表达与宫颈癌新辅助化疗治疗效果的相关性。方法选取2017年1月至2019年7月广东省第二人民医院收治的180例经临床确诊的宫颈癌患者作为研究对象,采用随机数字表法分为观察组和对照组,每组90例。对照组采用传统手术治疗和放疗;观察组实施收治治疗、放疗及新辅助化疗。统计比较两组治疗前后HSG、Ki67水平变化、临床疗效及不良反应发生率情况。结果观察组术后3周及术后6周HSG阳性表达率高于对照组,而Ki67阳性表达率低于对照组(P<0.05)。观察组疾病控制率(DCR)高于对照组(P<0.05)。结论宫颈患部HSG表达率与宫颈癌患者的康复情况呈正相关,而Ki67表达水平与宫颈癌患者DCR呈负相关。评估HSG及Ki67指标变化对宫颈癌新辅助化疗结果的评价具有重要的指导价值。     

Piperazine derivatives with central pharmacological activity used as therapeutic tools

Medicinal chemistry is a science applied to the search and discovery of new therapeutic agents for the treatment of various diseases. Therefore, promising structures have been identified; one of these structures is the piperazine moiety, a cyclic molecule containing two nitrogen atoms in positions 1 and 4 as well as four carbon atoms. Many piperazine derivatives have central pharmacological activity that mainly involves the activation of the monoamine pathway. Thus, piperazine derivatives have been the subject of research for many central therapeutic applications, including antipsychotic, antidepressant and anxiolytic applications. Benzylpiperazine is the prototype of piperazine derivatives; this substance is the main component of recreational drugs, partly due to its stimulant and euphoric effects. This paper describes some piperazine derivatives used therapeutically as antipsychotic (clozapine), antidepressant (vortioxetine) and anxiolytic (buspirone) drugs.     

BOPPPS教学模式在医科院校医用化学教学中的应用与思考

医用化学是医学院校一门重要的基础必修课程,内容多为知识理解型,这导致了学生兴趣薄弱,学习效果欠佳。因此,需要通过改革传统"灌输式"课堂授课方式,让学生真正参与到教学活动中。BOPPPS教学模式分为导言、学习目标、前测、参与式学习、后测和总结六个环节。突出"以学生为中心"的教学理念,遵循教学活动的客观规律。在医用化学课程的教学过程中引入BOPPPS教学,能够有效提高学生的课堂参与度,增强学生的学习动力,培养学生独立思考、自主学习的能力。