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31.
Zhang  Yanjun  Wang  Jing  Yang  Lulu  Niu  Jiaxin  Huang  Ruoqi  Yuan  Fang  Liang  Qiong 《International journal of legal medicine》2022,136(5):1261-1271

Papaver somniferum L. (opium poppy) is the original plant of heroin, which is a major narcotic drug, and this plant has brought great harm to human health. However, the ban on opium poppy cultivation and trafficking is facing great challenges because of abnormal profits. Therefore, rapid and accurate identification is important to address the abovementioned problems. In this study, eleven simple sequence repeats (SSR) markers and two single nucleotide polymorphism (SNP) markers were mined to distinguish opium poppy from other six Papaver species. These molecular markers were further verified through a large number of plant materials of these seven Papaver species. An excellent multiplex polymerase chain reaction (PCR) system that simultaneously amplifies the three of eleven SSR markers was developed, which effectively improves the efficiency and speed of identification. The present research is of great implication for identifying and investigating the illegal cultivation and trafficking of opium poppy.

  相似文献   
32.
BackgroundMuscle‐invasive bladder cancer (MIBC) is a heterogeneous disease with varying clinical courses and responses to treatment. To improve the prognosis of patients, it is necessary to understand such heterogeneity.MethodsWe used single‐sample gene set enrichment analysis to classify 35 MIBC cases into immunity‐high and immunity‐low groups. Bioinformatics analyses were conducted to compare the differences between these groups. Eventually, single‐cell mass cytometry (CyTOF) was used to compare the characteristics of the immune microenvironment between the patients in the two groups.ResultsCompared with patients in the immunity‐low group, patients in the immunity‐high group had a higher number of tumor‐infiltrating immune cells and greater enrichment of gene sets associated with antitumor immune activity. Furthermore, positive immune response‐related pathways were more enriched in the immunity‐high group. We identified 26 immune cell subsets, including cytotoxic T cells (Tcs), helper T cells (Ths), regulatory T cells (Tregs), B cells, macrophages, natural killer (NK) cells, and dendritic cells (DCs) using CyTOF. Furthermore, there was a higher proportion of CD45+ lymphocytes and enrichment of one Tc subset in the immunity‐high group. Additionally, M2 macrophages were highly enriched in the immunity‐low group. Finally, there was higher expression of PD‐1 and Tim‐3 on Tregs as well as a higher proportion of PD‐1+ Tregs in the immunity‐low group than in the immunity‐high group.ConclusionIn summary, the immune microenvironments of the immunity‐high and immunity‐low groups of patients with MIBC are heterogeneous. Specifically, immune suppression was observed in the immune microenvironment of the patients in the immunity‐low group.  相似文献   
33.
Neuroimaging studies using a variety of techniques have demonstrated abnormal patterns of spontaneous brain activity in patients with essential tremor (ET). However, the findings are variable and inconsistent, hindering understanding of underlying neuropathology. We conducted a meta‐analysis of whole‐brain resting‐state functional neuroimaging studies in ET compared to healthy controls (HC), using anisotropic effect‐size seed‐based d mapping, to identify the most consistent brain activity alterations and their relation to clinical features. After systematic literature search, we included 13 studies reporting 14 comparisons, describing 286 ET patients and 254 HC. Subgroup analyses were conducted considering medication status, head tremor status, and methodological factors. Brain activity in ET is altered not only in the cerebellum and cerebral motor cortex, but also in nonmotor cortical regions including prefrontal cortex and insula. Most of the results remained unchanged in subgroup analyses of patients with head tremor, medication‐naive patients, studies with statistical threshold correction, and the large subgroup of studies using functional magnetic resonance imaging. These findings not only show consistent and robust abnormalities in specific brain regions but also provide new information on the biology of patient heterogeneity, and thus help to elucidate the pathophysiology of ET.  相似文献   
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35.
Anti-agglomerants (AAs), both natural and commercial, are currently being considered for gas hydrate risk management of petroleum pipelines in offshore operations. However, the molecular mechanisms of the interaction between the AAs and gas hydrate surfaces and the prevention of hydrate agglomeration remain critical and complex questions that need to be addressed to advance this technology. Here, we use molecular dynamics (MD) simulations to investigate the effect of model surfactant molecules (polynuclear aromatic carboxylic acids) on the agglomeration behaviour of gas hydrate particles and disruption of the capillary liquid bridge between hydrate particles. The results show that the anti-agglomeration pathway can be divided into two processes: the spontaneous adsorption effect of surfactant molecules onto the hydrate surface and the weakening effect of the intensity of the liquid bridge between attracted hydrate particles. The MD simulation results also indicate that the anti-agglomeration effectiveness of surfactants is determined by the intrinsic nature of their molecular functional groups. Additionally, we find that surfactant molecules can affect hydrate growth, which decreases hydrate particle size and correspondingly lower the risk of hydrate agglomeration. This study provides molecular-level insights into the anti-agglomeration mechanism of surfactant molecules, which can aid in the ultimate application of natural or commercial AAs with optimal anti-agglomeration properties.

Schematic of anti-agglomeration effect of surfactants promoting gas hydrate particle dispersion.  相似文献   
36.
目的:评价64排螺旋CT冠状动脉成像(CTA)对冠状动脉解剖形态的显示能力及其临床应用。材料与方法:利用Philips Brilliance 64螺旋CT,通过工作站专用冠状动脉分析软件对冠状动脉进行三维重建,观察、测量冠状动脉的分支、位置、形态和变异。结果:成功行冠状动脉CTA的患者共358例,其中右侧优势型276例,左侧优势型39例,均衡型37例,共发现变异6例,其中1例两侧冠状动脉共同开口于左冠窦;1例左冠状动脉开口于肺动脉,4例副冠状动脉。358例中共发现76处心肌桥。结论:64排螺旋CT能较好显示冠状动脉的解剖形态,可以作为无创性冠状动脉成像的首选检查,同时对临床及插管法冠状动脉造影检查有一定的指导作用。  相似文献   
37.
A series of novel quinoxaline derivatives were synthesized and evaluated for their antiproliferative activity in three human cancer cell lines. Compound 12 exhibited the most potent antiproliferative activity with IC50 in the range of 0.19–0.51 μM. The compound inhibited tubulin polymerization and disrupted the microtubule network, leading to G2/M phase arrest. Furthermore, compound 12 induced ROS production and malfunction of mitochondrial membrane potential. Compound 12 led to cancer cells apoptosis in a dose‐dependent manner. Western blot analysis showed that compound 12 induced up‐regulation of p21 and affected the expression of cell cycle‐related proteins. The binding mode was also probed by molecular docking.  相似文献   
38.
The objective of the present study was to systematically investigate the influence of molecular weight (MW) and concentration of carboxymethyl chitosan (CMC), which served as non-collagenous protein (NCP) surrogates, on biomimetic mineralization of type I collagen. Supersaturated CMC-stabilized amorphous calcium-phosphate (CMC-ACP) dispersions containing different MWs (20 kDa, 60 kDa, 150 kDa) and concentrations (25, 50, 100, 200, 400 μg ml−1) of CMC were prepared. After mineralization in the aforementioned dispersions for 7 days, the pattern and extent of biomimetic mineralization of collagen scaffolds were investigated. Our study showed that increasing CMC concentration resulted in increasing stability and decreasing particle size of CMC-ACP dispersions. Images from scanning and transmission electron microscopy revealed that intrafibrillar mineralization of collagen was obtained with 20k-200, 60k-100, 60k-200 and 150k-200 CMC-ACP dispersions, with hydroxyapatite (HAp) formation confirmed by Fourier transform infrared spectroscopy and X-ray diffraction measurements, whereas HAp formed extrafibrillar clusters in other collagen scaffolds. Thermogravimetric analysis showed that the combined effect of MW and concentration of CMC contributed to different extents of biomimetic mineralization, and was correlated with the stability and particle size of CMC-ACP dispersions, and the size-exclusion characteristics of type I collagen. The results of this work support the effective function of CMC as NCP analogs, and provide parameters of MWs and concentrations of CMC for applications in hard tissue engineering as well as insights into intersections of mechanisms in biomimetic mineralization.

The study systematically investigated the influence of molecular weight and concentration of CMC on CMC-ACP nanoparticles and biomimetic mineralization.  相似文献   
39.
Constructing an ideal bone tissue engineering scaffold has been one of the research hotspots in the biomedical field. Silk fibroin (SF), nano-hydroxyapatite (nHAp) and graphene oxide (GO) are excellent biomaterials, and have been studied and explored extensively. To better mimic natural bone, we fabricated a SF/nHAp/GO hybrid scaffold with an oriented channel-like structure by using directional temperature field freezing technology. A comparative analysis was carried out for the SF, SF/nHAp, unoriented SF/nHAp/GO and oriented SF/nHAp/GO scaffolds. The physical and chemical properties were studied by scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy and universal mechanical testing. The data showed that the oriented channel-like SF/nHAp/GO porous scaffold expressed high interconnectivity, suitable pore diameter and porosity and anisotropic mechanical properties. Cytocompatibility tests indicated that the oriented channel-like SF/nHAp/GO porous scaffold was more favorable for stimulating bone marrow mesenchymal stem cells (BMSCs) adhesion and proliferation. Additionally, human umbilical vein endothelial cells (HUVECs) grew unimpeded along the channel, indicating it had advantages for vascularization. For further testing in vitro, osteogenic induction was carried out on BMSCs inoculated on the above scaffolds, and then alkaline phosphatase (ALP) activity was tested and cell mineralization was observed. The results indicated that the oriented channel-like SF/nHAp/GO porous scaffold was more conducive to osteogenic differentiation of BMSCs. Hence, the material may prove to be a promising scaffold for bone tissue engineering.

A novel SF/nHAp/GO hybrid scaffold with oriented channel-like structure in bone tissue engineering.  相似文献   
40.
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