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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   
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目的探讨孤儿核受体NURR1表达上调对前列腺癌细胞基因表达谱的影响。 方法构建NURR1过表达载体,通过慢病毒感染方式上调前列腺癌LNCaP细胞中NURR1的表达水平。通过免疫细胞化学染色检测NURR1蛋白的表达,通过基因表达谱芯片分析NURR1过表达组和对照组LNCaP细胞的mRNA、lncRNA表达水平的变化。通过KEEG和GO分析探讨NURR1过表达对相关信号通路和功能的影响。 结果NURR1基因在LNCaP细胞过表达,与对照组比较共有515个基因发生差异表达,其中上调的mRNA238个,下调的mRNA195个;上调的lncRNA54个,下调的lncRNA28个。差异表达的mRNA和lncRNA主要在于细胞分子功能的改变,其中视网膜结合功能、铁离子结合能力、神经轴突调控以及氧化还原过程、细胞外区域的细胞学组成改变最为显著。细胞因子与细胞因子受体的相互作用以及调节干细胞多能性的有关信号通路都发生显著性改变。 结论NURR1基因的上调表达对前列腺癌细胞mRNA以及lncRNA表达谱显著改变,可能与其促进前列腺癌进展的功能有关。  相似文献   
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Molecular markers can serve as diagnostic tools to support pathological analysis in thyroid neoplasms. However, because the same markers can be observed in some benign thyroid lesions, additional approaches are necessary to differentiate thyroid tumor subtypes, prevent overtreatment and tailor specific clinical management. This applies particularly to the recently described variant of thyroid cancer referred to as noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP). This variant has an estimated prevalence of 4.4% to 9.1% of all papillary thyroid carcinomas worldwide. We studied 60 thyroid lesions: 20 classical papillary thyroid carcinoma (CPTC), 20 follicular variant of PTC (FVPTC) and 20 NIFTP. We examined morphological and molecular features to identify parameters that can differentiate NIFTP from the other PTC subtypes. When blindly investigating the nuclear architecture of thyroid neoplasms, we observed that NIFTP has significantly longer telomeres than CPTC and FVPTC. Super-resolved 3D-structured illumination microscopy demonstrated that NIFTP is heterogeneous and that its nuclei contain more densely packed DNA and smaller interchromatin spaces than CPTC and FVPTC, a pattern that resembles normal thyroid tissue. These data are consistent with the observed indolent biological behavior and favorable prognosis associated with NIFTP, which lacks BRAFV600E mutations. Of note, next-generation thyroid oncopanel sequencing was unable to distinguish the thyroid cancer histotypes in our study cohort. In summary, our data suggest that 3D nuclear architecture can be a powerful analytical tool to diagnose and guide clinical management of NIFTP.  相似文献   
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AimsTrans fatty acids (TFAs) are unsaturated lipids either of industrial origin or naturally occurring in ruminant meat and milk. TFAs generated through food processing (industrial) is the main source in our diet and studies provide converging evidence on their negative effect on cardiovascular health. Since April 2021, the European Commission has put into effect a regulation for TFAs providing maximum 2% of total fat in all industrially produced foods. In light of this development, we review the evidence regarding the health attributes of different types of TFAs, their dietary sources and current intakes, and we describe the history of TFA-related legislative actions in an attempt to anticipate the efficiency of new measures.Data synthesisThe PubMed database was searched including original research (observational and intervention studies), systematic reviews and meta-analyses. Scientific reports of competent authorities and organizations have also been screened.ConclusionsTrans-fat elimination provides a fine example of how evidence has led to the application of horizontal regulatory measures regarding legal food ingredients in order to protect consumers’ health. In EU Member States, TFAs currently provide on average less than 1% of energy (1%E) and intakes marginally exceed recommendations primarily among young adults. Large dietary surveys however provide evidence for additional, less-well known sources of TFAs in the diet. Raising public awareness of “hidden” trans-fat found naturally in foods such as cheese, as well as of the trans-fat generated through traditional cooking practices is needed, if the goal to eliminate trans-fat from the diet is to be met.  相似文献   
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Background and objectivesInterstitial lung diseases (ILDs) are a varied group of disorders that have been clubbed together due to some common attributes. The data is abundant from the developed world. However, the developing countries have gradually amassed the knowledge of these disorders and epidemiological data is still missing. We aimed to profile the ILD patients at our center.MethodsAll ILD patients above the age of 14 years were included in the study. A detailed history, examination, exercise capacity assessment, pulmonary function test and relevant serological investigations were done. Tissue was obtained wherever possible. Diagnosis was made after discussion from concerned specialists.ResultsAmong the total 884 subjects recruited, 54% were females with a mean age of 53 years. Most were residents of rural areas. Reticulations and traction bronchiectasis was seen in most subjects. Hypersensitivity pneumonitis was present in 35.9% and connective-tissue disease related ILD (CTD-ILD) in 30.9%.ConclusionMost common ILDs at our center are hypersensitivity pneumonitis and CTD-ILD. Reticulations and traction bronchiectasis are the most common findings on HRCT thorax.  相似文献   
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BackgroundChildhood obesity places a major burden on global public health. We aimed to identify and characterize potential factors, both individually and jointly, in association with overweight and obesity in Chinese preschool-aged children.MethodsWe cross-sectionally recruited 9501 preschool-aged children from 30 kindergartens in Beijing and Tangshan. Overweight and obesity are defined according to the World Health Organization (WHO), International Obesity Task Force (IOTF), and China criteria.ResultsAfter multivariable adjustment, eating speed, sleep duration, birthweight, and paternal body mass index (BMI) were consistently and significantly associated with childhood overweight and obesity under three growth criteria at a significance level of 5%. Additional fast food intake frequency, maternal BMI, gestational weight gain (GWG) and maternal pre-pregnancy BMI were significant factors for overweight (WHO criteria) and obesity (both IOTF and China criteria). Importantly, there were significant interactions between parental obesity and eating speed for childhood obesity. Finally, for practical reasons, risk nomogram models were constructed for childhood overweight and obesity based on significant factors under each criterion, with good prediction accuracy.ConclusionOur findings indicated a synergistic association of lifestyle, fetal and neonatal, and family-related factors with the risk of experiencing overweight and obesity among preschool-aged children.  相似文献   
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Fever and cough are the most common clinical symptoms of coronavirus disease 2019 (COVID-19), but complications (such as pneumonia, respiratory distress syndrome, and multiorgan failure) can occur in people with additional comorbidities. COVID-19 may be a new cause of liver disease, as liver profile disturbance is one of the most common findings among patients. The molecular mechanism underlying this phenomenon, however, is still unknown. In this paper, we review the most current research on the patterns of change in liver profile among patients with COVID-19, the possible explanation for these findings, and the relation to pre-existing liver disease in these patients.  相似文献   
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