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排序方式: 共有3050条查询结果,搜索用时 15 毫秒
1.
《Saudi Pharmaceutical Journal》2022,30(11):1572-1588
Non-alcoholic fatty liver disease (NAFLD) is one of the most common complications of a metabolic syndrome caused by excessive accumulation of fat in the liver. Orthosiphon stamineus also known as Orthosiphon aristatus is a medicinal plant with possible potential beneficial effects on various metabolic disorders. This study aims to investigate the in vitro inhibitory effects of O. stamineus on hepatic fat accumulation and to further use the computational systems pharmacology approach to identify the pharmacokinetic properties of the bioactive compounds of O. stamineus and to predict their molecular mechanisms against NAFLD. Methods: The effects of an ethanolic extract of O. stamineus leaves on cytotoxicity, fat accumulation and antioxidant activity were assessed using HepG2 cells. The bioactive compounds of O. stamineus were identified using LC/MS and two bioinformatics databases, namely the Traditional Chinese Medicine Integrated Database (TCMID) and the Bioinformatics Analysis Tool for the Molecular Mechanism of Traditional Chinese Medicine (BATMAN-TCM). Pathway enrichment analysis was performed on the predicted targets of the bioactive compounds to provide a systematic overview of the molecular mechanism of action, while molecular docking was used to validate the predicted targets. Results: A total of 27 bioactive compounds corresponding to 50 potential NAFLD-related targets were identified. O. stamineus exerts its anti-NAFLD effects by modulating a variety of cellular processes, including oxidative stress, mitochondrial β-oxidation, inflammatory signalling pathways, insulin signalling, and fatty acid homeostasis pathways. O. stamineus is significantly targeting many oxidative stress regulators, including JNK, mammalian target of rapamycin (mTOR), NFKB1, PPAR, and AKT1. Molecular docking analysis confirmed the expected high affinity for the potential targets, while the in vitro assay indicates the ability of O. stamineus to inhibit hepatic fat accumulation. Conclusion: Using the computational systems pharmacology approach, the potentially beneficial effect of O. stamineus in NAFLD was indicated through the combination of multiple compounds, multiple targets, and multicellular components.  相似文献   
2.
《Vaccine》2022,40(27):3721-3726
We initiated a randomized, placebo-controlled, phase 1/2 trial to evaluate the safety and immunogenicity of the S-268019-b recombinant protein vaccine, scheduled as 2 intramuscular injections given 21 days apart, in 60 randomized healthy Japanese adults. We evaluated 2 regimens of the S-910823 antigen (5 μg [n = 24] and 10 μg [n = 24]) with an oil-in-water emulsion formulation and compared against placebo (n = 12). Reactogenicity was mild in most participants. No serious adverse events were noted. For both regimens, vaccination resulted in robust IgG and neutralizing antibody production at days 36 and 50 and predominant T-helper 1-mediated immune reaction, as evident through antigen-specific polyfunctional CD4+ T-cell responses with IFN-γ, IL-2, and IL-4 production on spike protein peptides stimulation. Based on the interim analysis, the S-268019-b vaccine is safe, produces neutralizing antibodies titer comparable with that in convalescent serum from COVID-19-recovered patients. However, further evaluation of the vaccine in a large clinical trial is warranted.  相似文献   
3.
Controlling cellular alignment is critical in engineering intestines with desired structure and function. Although previous studies have examined the directional alignment of cells on the surface (x–y plane) of parallel fibers, quantitative analysis of the cellular alignment inside implanted scaffolds with oriented fibers has not been reported. This study examined the cellular alignment in the x–z and y–z planes of scaffolds made with two layers of orthogonally oriented fibers. The cellular orientation inside implanted scaffolds was evaluated with immunofluorescence. Quantitative analysis of coherency between cell orientation and fiber direction confirmed that cells aligned along the fibers not only on the surface (x–y plane) but also inside the scaffolds (x–z & y–z planes). Our study demonstrated that two layers of orthogonally aligned scaffolds can generate the histological organization of cells similar to that of intestinal circular and longitudinal smooth muscle.  相似文献   
4.
《Vaccine》2020,38(1):20-28
During the last few decades, maternal immunization as a strategy to protect young infants from infectious diseases has been increasingly recommended, yet some issues have emerged. Studies have shown that for several vaccines, such as live attenuated, toxoid and conjugated vaccines, high maternal antibody titers inhibit the infant’s humoral immune response after infant vaccination. However, it is not clear whether this decreased antibody titer has any clinical impact on the infant’s protection, as the cellular immune responses are often equally important in providing disease protection and may therefore compensate for diminished antibody levels. Reports describing the effect of maternal antibodies on the cellular immune response after infant vaccination are scarce, probably because such studies are expensive, labor intensive and utilize poorly standardized laboratory techniques. Therefore, this review aims to shed light on what is currently known about the cellular immune responses after infant vaccination in the presence of high (maternal) antibody titers both in animal and human studies. Overall, the findings suggest that maternally derived antibodies do not interfere with the cellular immune responses after infant vaccination. However, more research in humans is clearly needed, as most data originate from animal studies.  相似文献   
5.
目的:了解循环张应力对小鼠颅底蝶枕软骨联合细胞(SOSCs)增殖及低氧诱导因子-1α表达的影响。方法:采集1 d龄小鼠的SOSCs进行体外培养,对第三代细胞加载牵张形变率分别为3%、6%、9%,频率为1 Hz,持续时间为1 h的循环张应力;用流式细胞术测算细胞增殖指数,用蛋白免疫印迹技术分析Hif-1α的表达水平。用按相同条件培养但不加力的细胞作为对照。结果:各实验组细胞的增殖指数和Hif-1α相对表达量都高于对照组(P<0.05);其中,6%牵张形变率组的细胞增殖指数和Hif-1α相对表达量较对照组增加最多。结论:适宜强度的循环张应力对体外培养小鼠SOSCs的增殖和Hif-1α表达具有促进作用。  相似文献   
6.
Breast cancer is the most common malignancy in women worldwide, with a relatively high proportion of patients experiencing resistance to standard treatments. Cellular immunotherapy (CI), which is based on the extraction, modification, and re-infusion of the patient’s immune cells, is showing promising results in these patients. Among CI possible approaches, adoptive cell therapy (ACT) and dendritic cell (DC) vaccination are the most comprehensively explored in both primary/translational research studies and clinical trials. ACT may include the use of tumor-infiltrating lymphocytes (TILs), T cell receptor (TCR)-, or chimeric antigen receptor (CAR)-engineered T-cells. There are indications suggesting that a biomarker-based approach might be beneficial in effectively selecting breast cancer patients for CI. Here, we sought to provide the current knowledge of CI in breast cancer, focusing on candidate biomarkers, ongoing clinical trials, limitations, and immediate future perspectives.  相似文献   
7.
This paper presents theoretical results on the convergence and attractivity of memristor-based cellular neural networks (MCNNs) with time delays. Based on a realistic memristor model, an MCNN is modeled using a differential inclusion. The essential boundedness of its global solutions is proven. The state of MCNNs is further proven to be convergent to a critical-point set located in saturated region of the activation function, when the initial state locates in a saturated region. It is shown that the state convergence time period is finite and can be quantitatively estimated using given parameters. Furthermore, the positive invariance and attractivity of state in non-saturated regions are also proven. The simulation results of several numerical examples are provided to substantiate the results.  相似文献   
8.
探讨E-钙粘附素(E-Cd)对人胃癌侵袭性的作用。方法:应用酶联免疫吸附方法测定29例胃癌患者血清可溶性E-Cd浓度。结果:胃癌组明显高于对照组(P<0.01),浸润组或有淋巴结转移组明显高于膨胀组或无淋巴结转移组(P<0.01~0.05),切除瘤体后上述各组的血清E-Cd浓度均明显下降(P<0.01~0.05)。结论:血清可溶性E-Cd浓度可能与人胃癌的生长方式和淋巴结转移密切相关。  相似文献   
9.
目的:观察青海高原地区幽门螺杆菌(Hp)相关性胃癌前病变患者血清Th1/Th2细胞因子(IL-1β、IL-2、IL-4、IL-6、IL-8、TNF)水平变化,以探讨其在发病中的可能免疫致病机制。方法:应用放免法(RIA)测定25例慢性萎缩性胃炎(CAG)、17例肠化生(IM)、15例异型增生(Dys)患者血清IL-1β、IL-2、IL-4、IL-6、IL-8、TNF的含量。比较Hp感染与非感染胃癌前病变患者之间;Hp感染CAG炎症活动与非活动患者之间;Hp感染CAG、IM、Dys患者之间血清6种细胞因子含量的差别。结果:Hp感染与非感染胃癌前病变患者之间6种细胞因子含量均无显著性差别(P>0.05);Hp感染CAG炎症活动者血清IL-4含量显著低于非活动者(P<0.05);IM和Dys者均非常显著低于CAG(P<0.01),IL-2在Dys组显著高于CAG(P<0.05)。结论:本地区Hp相关性胃癌前病变中存在血清Th1/Th2失衡,表现为随着胃癌前病变的逐级加重,T淋巴细胞高表达IL-2伴随IL-4低表达现象。  相似文献   
10.
铜绿假单胞菌全细胞脂肪酸气相色谱分析及应用   总被引:5,自引:0,他引:5  
本研究用计算机控制,可程序升温的毛细管柱气相色谱(GC)仪分析48株铜绿假单胞菌标准株和临床株、部分常见假单胞菌、肠杆菌的细胞脂肪酸。结果表明:月桂烯酸(C12:1),月桂酸(C12:0)、十三碳烯酸(C13:1)、十三碳酸(C13:0)、肉豆劳动脑酸(C14:1)、十七碳稀酸(C17:1)、十七碳酸(C17:0)、硬脂酸(C18:0)和花生四烯酸(C20:4)是铜绿包菌有鉴别意义的脂肪酸,组成与  相似文献   
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