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.     

蕲蛇的鉴别研究进展＊

蕲蛇是《中国药典》收载的三种蛇类药材（含蕲蛇、乌梢蛇、金钱白花蛇）之一，具有祛风、通络、定惊止痉等功效，其药用价值和经济价值较高，市场需求量较大，为贵细药材。近年来，由于野生资源逐渐匮乏，在经济利益驱使下，蕲蛇商品普遍存在着伪品、混淆品、掺假品，这种质量不一、以次充好、以假代真的情况容易导致用药安全问题。本文通过总结蕲蛇的性状鉴别、显微鉴别、理化鉴别和分子鉴别，以期为蕲蛇等蛇类药材的真伪鉴别和质量的优劣检测提供思路，为进一步鉴别研究、制剂开发提供参考依据，确保用药质量。     

双重实时荧光PCR快速鉴别人参和西洋参＊

目的 建立一种能够快速鉴定人参和西洋参的双重实时荧光PCR方法。方法 通过对人参属及其近似种基因序列的分析比对，设计特异性的引物探针，建立双重实时荧光PCR检测方法。PCR反应体系为Premix Ex Taq （Probe qPCR） 10 μL，人参上下游引物各0.5 μL，西洋参上下游引物各0.3 μL，人参与西洋参特异性探针各0.4 μL，DNA模板2 μL，灭菌去离子水补至20 μL。反应条件为95℃预变性30 s；然后以95℃变性5 s，60℃退火延伸30 s进行40个循环。应用该方法测试了27份DNA样品，包括7份人参、6份西洋参、4份人参与西洋参混合样、10份其他人参属样品及其他常见中药材样品的DNA，以确定该方法的特异性。将人参与西洋参样品DNA混合后10倍稀释成不同浓度后进行检测，用以确定该方法的灵敏度。结果 人参及西洋参样品均在特定的荧光通道下出现典型的阳性扩增曲线，人参与西洋参混合样品均同时出现两条阳性扩增曲线，其它对照样品及空白对照均没有出现阳性扩增曲线。灵敏度检测结果显示该方法检测人参及西洋参的最低检测限均为2 pg DNA/反应。结论 本实验建立的双重实时荧光PCR方法能够同时快速、准确、灵敏地鉴别出人参和西洋参。     

毛霉目病原真菌的实验室鉴定及体外抗真菌药物敏感 性分析

摘要:目的以分子测序为参考 ,评估形态学、基质辅助激光解吸电离飞行时间质谱对毛霉目真菌的鉴定能力,分析毛霉目真菌对两性霉素B、泊沙康唑的体外药敏特点。方法收集 2018年1月-2022年2月广东省人民医院25例毛霉病住院患者标 本,进行镜检并对培养的茵落行形态学鉴定、质谱鉴定、分子测序和体外药敏试验。结果KOH 湿片法阳性率(76%)高于革兰染色法(32%),差异有统计学意义(P<0.05);形态学鉴定可将68%的菌株鉴定到属水平,3株鉴定错误,2株无法鉴定;将所 有菌株进行质谱鉴定,单用IVD和RUO数据库鉴定率分别为56%和44%,两库联合可将鉴定率提高为64%。毛霉目真菌对两性霉素B的抑制50%菌株生长的最小抑菌浓度(MIC3o)为1μg/mL,根霉属相比其他属对两性霉素B表现出较高的MIC 值,其中2株MIC>32 μg/mL,另2株MIC为8 μg/mL;根霉属对泊沙康唑的MICso为0.5 μg/mL,横梗霉属MICgo为4 μg/ mL,小克银汉霉属MICg0为2 μg/mL,有部分菌株表现出较低MIC值,同样亦有部分菌株对泊沙康唑表现出较高的MIC 值。结论 将传统镜检、培养与质谱技术和分子技术相结合,尽量将毛霉目真菌准确鉴定到种,并积极开展毛霉体外药敏试验,可为临床治疗提供参考依据。     

Utilidad de la fluorescencia cercana al infrarrojo para la identificación del bronquio segmentario en segmentectomías mínimamente invasivas

Minimally invasive anatomical sublobar resections have gained relevance in recent years mainly due to advances in imaging techniques, screening programs and the increase in second neoplasms. Accurate identification of the segmental or subsegmental bronchus is vital to guarantee optimal results in segmentectomies and subsegmentectomies. Given the complexity and the possibility of anatomical variations, several authors have published different methods to identify the target bronchus. However, these methods have certain limitations. This article describes a new rapid and effective technique, with a low risk of complications and without additional cost, for the identification of segmental bronchi in minimally invasive segmentectomies.     

Application of 3D imaging and selfies in forensic dental identification

With increased access to smartphones, the selfie has gained immense popularity in the past decade. Selfie images could be a significant source of ante-mortem (AM) image data in cases where dental records are unavailable or considered insufficient. The application of 3D imaging and selfies has not been explored to its full potential in human dental identification. The present study aimed to evaluate the feasibility of using selfies as AM data and comparing with 3D post-mortem (PM) scans as an alternative to multiple 2D PM photographs in forensic dental identification. The study sample consisted of 18 selfies (12 matching and 6 non-matching) and 15 3D dental scans obtained from the study participants. The study sample was assessed by 6 experienced forensic odontologists (Raters) in two phases; Phase I-Visual comparison of 2D selfies to 3D scans and Phase II-2D selfies superimposed upon 3D scans. Each rater looked at 15 cases, and a total of 1620 comparisons were made by 6 raters (72 for the 12 matching cases and 1548 were for non-matching) and the opinions for each of the comparisons were analyzed. The results of the study show that use of the 3D superimposition method increased the certainty of the conclusions reached by the raters for the cases with correct matches. Furthermore, 94.2% of the 1548 non-matching comparisons were correctly excluded, compared with 77% for the 2D visual comparison method. The study demonstrated the applicability of this 3D method as a valuable tool in assisting the forensic odontologist with dental identification using selfies.     

三七片DNA条形码分子鉴定及方法学考察

目的为研究DNA条形码技术在中成药鉴定中的应用,以三七片为研究对象,对方法的适用性、专属性与精密度进行考察。方法收集15批次市售三七片样品,考察三七片DNA提取条件,并对"中药材DNA条形码分子鉴定法指导原则"中PCR扩增、序列获得、结果判定等方法适用性进行确认;收集三七、人参、西洋参,制作三七片及其掺伪品,考察方法的专属性和重现性。结果三七片取样量100 mg,56℃水浴8 h所获得DNA的质量浓度平均值为60.7 ng/μL,PCR扩增、序列获得和结果判定均可获成功;三七、人参和西洋参的ITS2序列长度均为230bp,三七与人参、三七与西洋参的序列间均存在7个稳定的SNP位点,自制三七片和掺伪三七片均可成功获得ITS2序列,不同比例三七与人参、三七与西洋参的测序峰图在SNP位点处呈现相应峰高比的SNP套峰具备专属性;重复性、中间精密度和重现性考察符合《中国药典》2015年版(通则9101)相关要求。结论 ITS2序列作为DNA条形码能够稳定、准确鉴定三七片的原料药材,具备良好的专属性和精密度,三七片DNA条形码分子鉴定法将为保障三七片临床用药安全提供新的技术手段,并对《中国药典》其他收载单方制剂的鉴定提供参考。     

HPLC-MS法鉴定广西产拳卷地钱中5种黄酮类成分

目的采用HPLC-MS鉴定广西产拳卷地钱75%乙醇提取物中黄酮类成分。方法采用色谱柱:ACQUITY UPLC HSS T3 C18(2.1 mm×100 mm,1.8μm),流动相为0.1%甲酸水(A)-乙腈(B),梯度洗脱,质谱使用电喷雾电离源(ESI)正负离子模式。结果分析得出拳卷地钱含有黄酮类成分5个,分别是Apigenin7,4’-diglucuronide、Apigenin7-glucuronide、芹菜素、木犀草素、金圣草黄素。结论该方法稳定、准确性好,可用于广西产拳卷地钱成分鉴定及质量控制。     

中医健康状态辨识模式的研究现状与展望

健康状态的辨识是把握健康的前提。当前学界已存在专家辨识模式、标准辨识模式、数字辨识模式、智能辨识模式以及微观辨识模式等。联合多种辨识方法,构建健康状态辨识体系,形成常态与动态结合、主观与客观结合、人机互参的中医健康状态个体化辨识方法是研究的趋势所在。文章对未来的研究方向进行展望,探讨了多元辨识模式、远程辨识模式、终身辨识模式、自动辨识模式的思路方法,以期促进全民健康事业,助力"健康中国"战略。     

临泉产穿心莲地上部分黄酮类化学成分研究

目的:研究临泉产穿心莲地上部分黄酮类化学成分。方法:利用硅胶、凝胶Sephadex LH-20、ODS柱色谱等方法,对临泉产穿心莲地上部分90%乙醇提取物的化学成分进行分离和纯化,运用波谱学技术对分离得到的单体化合物进行结构鉴定。结果:从穿心莲的乙醇提取物中分离并鉴定出14个黄酮类化合物,分别是双氢汉黄芩素(1)、5-羟基-6,7-二甲氧基黄酮(2)、2-羟基-3,4,6-三甲氧基查尔酮(3)、5-羟基-7,8-二甲氧基黄酮(4)、穿心莲素(5)、5-羟基-7,8,2',5'-四甲氧基黄酮(6)、5,7,8-三甲氧基二氢黄酮(7)、2'-甲氧基-5,6,7-三甲基黄芩素(8)、5,7,4'-三甲氧基黄酮(9)、高车前素(10)、7,8,2',5'-四甲氧基黄酮-5-O-β-D-吡喃葡萄糖苷(11)、穿心莲黄酮苷A(12)、穿心莲黄酮苷C(13)、穿心莲黄酮苷G(14)。结论:其中化合物1、2、3、8首次从穿心莲中分离得到。