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1.
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.  相似文献   
2.
Tsukamurella species are obligate aerobic, gram-positive, weak acid-fast, nonmotile bacilli. They are found in various environments, such as soil, water, sludge, and petroleum reservoir wastewater, and belong to the order Actinomycetales. In 2016, there was a reclassification of species within the genus Tsukamurella, merging the species Tsukamurella tyrosinosolvens (T. tyrosinosolvens) and Tsukamurella carboxydivorans. Tsukamurella species are clinically considered to be a rare opportunistic pathogen, because most reported cases have been related to bacteremia and intravascular prosthetic devices and immunosuppression. To date, it has been isolated only from human specimens, and has always been associated with clinical disease; human infections are very rare. Reported infections have included pneumonia, brain abscesses, catheter-related bloodstream infections, ocular infections, bacteremia, and sepsis presenting with septic pulmonary emboli in patients who are immunocompromised. To date, there is no commercially available test for identification. On the other hand, sequence-based identification, including matrix-assisted laser desorption ionization time-of-flight mass spectrometry, is an alternative method for identifying clinical isolates that are either slow growers or difficult to identify through biochemical profiling. The golden standards for diagnosis and optimal management still remain to be determined. However, newer molecular biological techniques can provide accurate identification, and contribute to the appropriate selection of definitive therapy for infections caused by this organism. Combinations of several antimicrobial agents have been proposed for treatment, though the length of treatment for infections has yet to be determined, and should be individualized according to clinical response. Immunocompromised patients often experience severe cases due to infection, and life-threatening T. tyrosinosolvens events associated with dissemination and/or failure of source control have occurred. Favorable prognoses can be achieved through earlier identification of the cause of infection, as well as successful management, including appropriate antibiotic therapy together with source control. Further analyses of similar cases are required to establish the most adequate diagnostic methods and treatment regimens for infections.  相似文献   
3.
ObjectivesWe investigated whether nanopore 16S amplicon sequencing is capable of bacterial identification in patients with knee prosthetic joint infection (PJI), and we compared its efficacy with conventional culture studies.MethodsIn total, 36 patients who had clinical manifestation suspected of PJI were enrolled in this study. To begin, synovial fluids were aspirated from the affected knee using aseptic technique and tissues specimens were obtained during the surgery. Next, DNA was extracted from the synovial fluid or tissues, and 16S rDNA PCR was performed. In PCR positive cases, nanopore amplicon sequencing was then performed for up to 3 h. The results of amplicon sequencing were compared to those of conventional culture studies.ResultsOf the 36 patients enrolled, 22 were classified as true infections according to the MSIS criteria whereas 14 were considered uninfected. Among the 22 PJI cases, 19 cases were culture positive (CP-PJI) while three cases were culture negative (CN-PJI). In 14 of 19 (73.7 %) CP- PJI cases, 16S sequencing identified concordant bacteria with conventional culture studies with a significantly shorter turnaround time. In some cases, nanopore 16S sequencing was superior to culture studies in the species-level identification of pathogen and detection of polymicrobial infections. Altogether, in the majority of PJI candidate patients (32 of 36, 88.9 %), 16S sequencing achieved identical results to cultures studies with a significantly reduced turnaround time (100.9 ± 32.5 h vs. 10.8 ± 7.7 h, p < 0.001).ConclusionsNanopore 16S sequencing was found to be particularly useful for pathogen identification in knee PJI. Although the sensitivity was not superior to culture studies, the nanopore 16S sequencing was much faster, and species-level identification and detection of polymicrobial infections were superior to culture studies.  相似文献   
4.
把握状态是维护健康的关键。中医美容健康管理体系以状态辨识为核心,对皮肤、形体局部状态及整体健康状态进行辨识、干预、评价,从而对损美性疾病进行管理与维护。中医美容健康管理体系应重视三观并用及四态管理,即从宏观、中观、微观的三观层面采集皮肤、形体与整体状态的参数信息,整体审查、四诊合参,对皮肤、形体与整体所处的未病状态、欲病状态、已病状态和病后状态进行辨识和诊断,并运用相应的干预手段,对状态进行调整。同时,应规范中医美容健康管理服务的流程,着重解决中医美容健康管理体系构建中5个核心内容的关键问题,为求美者提供整体、动态、个性化的管理服务,对促进中医健康管理与中医美容的交叉与融合,维护人体的健康美具有重要意义。  相似文献   
5.
目的:将彩色多普勒超声检查对肉芽肿性乳腺炎、乳腺癌的鉴别诊断价值进行分析。方法:对本院2018年3月~2019年3月收治的60例肉芽肿性乳腺炎患者与60例乳腺癌患者的彩色多普勒超声诊断进行回顾性分析,并将其超声表现进行对比与研究。结果:在60例肉芽肿性乳腺炎患者的超声结果中发现,52例患者为单发性肉芽肿性乳腺炎,38例患者病灶部位位于左侧乳腺,14例患者病灶部位位于右侧乳腺,8例患者为多发性肉芽肿性乳腺炎。乳腺腺体实性肿块37例,呈假肾征,且腺体可见稍强回声,60例乳腺癌患者超声表现均为实性肿块,且边缘不规则,腺体内部可见不均质低回声,边缘可见形态不规则,厚度不均晕环,肉芽肿性乳腺炎患者的病灶肿块范围明显大于乳腺癌患者(P<0.05)。肉芽肿性乳腺炎以及乳腺癌患者的超声声像图比较,差别较大(P<0.05)。结论:肉芽肿性乳腺炎与乳腺癌的彩色多普勒超声表现不同,可作为对肉芽肿性乳腺炎与乳腺癌鉴别诊断的首选检查方式。  相似文献   
6.
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。  相似文献   
7.
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。  相似文献   
8.
目的 了解新疆维吾尔自治区哈密市蚊虫种类及病毒携带情况,并鉴定该市尖音库蚊所属亚种。方法 分别于2019、2020年7月中旬,在新疆维吾尔自治区哈密市伊州区、伊吾县、巴里坤县采用诱蚊灯法捕捉蚊虫,鉴定所捕获蚊虫种属及尖音库蚊种属。采用逆转录PCR技术检测捕获蚊虫携带黄病毒属、甲病毒属、布尼亚病毒属、流行性乙型脑炎病毒、辽宁病毒、Tahyna病毒、蜱传脑炎病毒及西尼罗病毒情况。结果 在哈密市伊州区、伊吾县、巴里坤县共捕获蚊虫1 496只,分属于3属3种。尖音库蚊为优势蚊种,占所捕获蚊虫总数的65.91%(986只);其次为里海伊蚊,占30.55%(457只);阿拉斯加脉毛蚊最少,仅占3.54%(53只)。所捕获尖音库蚊经雄蚊尾器鉴定为尖音库蚊指名亚种。经逆转录PCR法检测,所捕获蚊虫黄病毒属、甲病毒属、布尼亚病毒属、流行性乙型脑炎病毒、辽宁病毒、Tahyna病毒、蜱传脑炎及西尼罗病毒均为阴性。结论 2019—2020年哈密市存在尖音库蚊、里海伊蚊、阿拉斯加脉毛蚊3种蚊虫,以尖音库蚊为优势蚊种;所捕获尖音库蚊均为指名亚种,未发现蚊类携带相关虫媒病毒。  相似文献   
9.
【目的】对市售54批次蜂蜜中的微生物污染情况进行调查分析。【方法】依据食品安全国家标准对蜂蜜中菌落总数、霉菌计数和嗜渗酵母计数进行检测和判定,通过形态学、基质辅助激光解吸电离飞行时间质谱、大亚基单元核糖体RNA基因序列对不合格样品中的细菌和真菌进行鉴定和分析。【结果】共3批次蜂蜜微生物超标,其中菌落总数超标1批次,检出包括芽孢杆菌属(Bacillus sp.)、类芽孢杆菌属(Paenibacillus sp.)和短芽孢杆菌属(Brevibacillus sp.)中的多种细菌;霉菌计数超标2批次,样品来源于同一生产企业,均检出曲霉(Aspergillus sp.)且微生物序列同源性高度一致,可能来自同一污染源。【结论】蜂蜜微生物污染种类多,蜂蜜生产企业应加强蜂蜜生产过程的微生物控制,避免重复污染。  相似文献   
10.
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