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991.
Brain cancer, also known as intracranial cancer, is one of the most invasive and fatal cancers affecting people of all ages. Despite the great advances in medical technology, improvements in transporting drugs into brain tissue have been limited by the challenge of crossing the blood-brain barrier (BBB). Fortunately, recent endeavors using gold-based nanomaterials (GBNs) have indicated the potential of these materials to cross the BBB. Therefore, GBNs might be an attractive therapeutic strategy against brain cancer. Herein, we aim to present a comprehensive summary of current understanding of the critical effects of the physicochemical properties and surface modifications of GBNs on BBB penetration for applications in brain cancer treatment. Furthermore, the most recent GBNs and their impressive performance in precise bioimaging and efficient inhibition of brain tumors are also summarized, with an emphasis on the mechanism of their effective BBB penetration. Finally, the challenges and future outlook in using GBNs for brain cancer treatment are discussed. We hope that this review will spark researchers’ interest in constructing more powerful nanoplatforms for brain disease treatment. 相似文献
992.
Zhenling Guo Sanfang Tu Siyao Yu Liufang Wu Wanying Pan Ning Chang Xuan Zhou Chaoyang Song Yuhua Li Yanjie He 《Cancer science》2021,112(4):1357-1368
In recent years, the excellent curative effect of CD19-specific chimeric antigen receptor (CAR) T-cell therapy has brought hope to patients with relapsing or refractory B-cell hematological malignancies, however relapse after CAR T-cell infusion has hindered the widespread clinical application of this immunotherapy and targeted antigen-negative relapse has caused widespread concern. Consequently, strategies for increasing targeted antigens have been created. In addition to the most widely applied target, namely CD19, researchers have further explored the possibility of other targets, such as CD20, CD22, CD33, and CD123, and have tested a series of combination antigen CAR T-cell therapies. Here, we summarize the current preclinical and clinical studies of dual-target CAR T cells. 相似文献
993.
Minh NH Minh TB Iwata H Kajiwara N Kunisue T Takahashi S Viet PH Tuyen BC Tanabe S 《Archives of environmental contamination and toxicology》2007,52(4):458-465
Surficial sediment samples were collected from Hochiminh City canals, the Sai Gon–Dong Nai River, and its estuary, one of
the most predominant industrial areas in Hochiminh City, southern Vietnam, for determination of selected persistent organic
pollutants (POPs). Contamination pattern was as follows: PCBs ≥ DDTs > HCB > CHLs > HCHs. Concentrations of PCBs and DDTs
ranged from 0.50–150 ng/g and 0.15–72 ng/g dry wt, respectively. On the other hand, concentrations of CHLs, HCHs, and HCB
were mostly <2 ng/g dry wt. Levels of the all organochlorines (OCs) in Hochiminh City canals were significantly higher than
those in the other areas, indicating the urban areas as major pollution sources to the aquatic environment. The contamination
pattern was PCBs > DDTs in the city canals but PCBs < DDTs in the downstream and the estuary, suggesting particularly high
contamination by PCBs in the city. Examination of DDTs composition and their ratios demonstrated continuous input of this
pesticide to the city canals. However, the combination of our data and those from available literature implies a decreasing
trend of PCBs and DDTs in the environment. DDTs concentrations have been reduced 50% after approximately 5 years. Composition
of CHLs in the sediment from Hochiminh City canals was comparable to those of common technical mixtures, suggesting continuous
input of CHLs to the environment. CHLs might be in use for purposes like termite control, wood preservation, and protection
of underground cables. Hazard assessment implies high toxic potential of DDTs for sediments from Hochiminh City canals and
suggests the need for better management of municipal discharges. 相似文献
994.
We examined the therapeutic efficacy of xenogenic human N'-terminal neu DNA vaccine and autologous mouse N'-terminal neu DNA vaccine on MBT-2 tumor cells in C3H mice. Intramuscular injection of xenogenic and autologous neu DNA vaccines produced comparable therapeutic efficacies. Mouse and human N'-neu DNA vaccine induced tumor infiltration of CD8(+) T cells, while the human vaccine was less effective at stimulating natural killer cells. Depletion of CD8(+) T cells abolished the therapeutic efficacy of both types of DNA vaccines. On the other hand, xenogenic neu DNA vaccine showed significantly better therapeutic efficacy than autologous DNA vaccine with gene gun immunization. Increased infiltration of CD8(+) T cells was correlated with enhanced therapeutic efficacy in the human N'-neu group of mice. Therefore, intramuscular injection can enhance the therapeutic efficacy of autologous neu DNA vaccine. 相似文献
995.
The four models proposed for exploring the foetal origins of adult disease (FOAD) hypothesis use the product term between
size at birth and current size to determine the relative importance of pre- and post-natal growth on disease in later life.
This is a common approach for testing the interaction between an exposure (in this instance size at birth) and an effect modifier
(in this instance current size)—incorporating the product term obtained by multiplying the exposure and effect modifier variables
within a statistical regression model. This study examines the mathematical basis for this approach and uses computer simulations
to demonstrate two potential statistical flaws that might generate misleading findings. The first of these is that the expected
value of the partial regression coefficient for the product term (between exposure and effect modifier) will be zero when
the outcome, exposure and effect modifier are all continuously distributed and follow a multivariate normal distribution.
This is because testing the product interaction term amounts to testing for multivariate normality among the three variables,
irrespective of the pair-wise correlations amongst them. The second flaw is that it is possible to generate a statistically
significant interaction between exposure and effect modifier, even when none exists, simply by categorising either or both
of these variables. These flaws pose a serious challenge to the four models approach proposed for exploring the FOAD hypothesis.
The interaction between exposure and effect modifier variables should be interpreted with caution both here and elsewhere
in epidemiological analyses. 相似文献
996.
Khaing Zar Thin Xuefang Liu Xiaobo Feng Sudheesh Raveendran Jian Cheng Tu 《Pathology, research and practice》2018,214(6):801-805
Objectives
Long noncoding RNAs (lncRNA) are a type of noncoding RNA that comprise of longer than 200 nucleotides sequences. They can regulate chromosome structure, gene expression and play an essential role in the pathophysiology of human diseases, especially in tumorigenesis and progression. Nowadays, they are being targeted as potential biomarkers for various cancer types. And many research studies have proven that lncRNAs might bring a new era to cancer diagnosis and support treatment management. The purpose of this review was to inspect the molecular mechanism and clinical significance of long non-coding RNA- differentiation antagonizing nonprotein coding RNA(DANCR) in various types of human cancers.Materials and methods
In this review, we summarize and figure out recent research studies concerning the expression and biological mechanisms of lncRNA-DANCR in tumour development. The related studies were obtained through a systematic search of PubMed, Embase and Cochrane Library.Results
Long non-coding RNAs-DANCR is a valuable cancer-related lncRNA that its dysregulated expression was found in a variety of malignancies, including hepatocellular carcinoma, breast cancer, glioma, colorectal cancer, gastric cancer, and lung cancer. The aberrant expressions of DANCR have been shown to contribute to proliferation, migration and invasion of cancer cells.Conclusions
Long non-coding RNAs-DANCR likely serves as a useful disease biomarker or therapeutic cancer target. 相似文献997.
早产儿用面罩给氧后抗氧化水平的变化 总被引:1,自引:0,他引:1
目的:了解早产患儿氧化应激反应能力,以指导临床合理用氧。方法:60例早产儿分为3组,AB2组均给氧治疗,C组不用氧。治疗前后监测3组血浆中谷胱甘肽(GSH)和丙二醛(MDA)值。结果:AB2组组血浆GSH含量均低于C组,给氧时间越长,氧浓度越高,GSH含量越低;AB2组MDA均高于C组,且随着氧浓度和给氧时间的增加而增高。结论:早产患儿对高氧暴露的反应能力低下,长时间高浓度的氧疗可使其抗氧化能力降低,即使在面罩给氧化和抗氧化的动态平衡也有改变,如产生的自由基超过机体的清除能力,机体将受到相应损害,故建立临床上应注意合理用氧。 相似文献
998.
人工心脏起搏器置人术是治疗多种严重心律失常的有效方法之一,随着电子工艺技术的不断发展,更多用途的生理性起搏器置入比例逐年增加。作为一种创伤性治疗,其并发症也十分常见,严重的并发症往往影响病人的预后,但一些非心脏并发症容易被人们忽视,如果这些并发症处理不当,亦会危及病人生命。因此,采取合理的护理模式对人工心脏起搏器置入术后病人进行严密观察,可早期预防、发现并发症,提高临床治愈率。 相似文献
999.
目的:观察常见的运动性疲劳症状指标血红蛋白和免疫功能的变化,分析健脾生血、补肾中药组方对划船运动员运动性疲劳症状的影响。方法:纳入2004-03-04/2004-03-24山东省水上运动学校的男运动员20名,皮艇8名,赛艇12名,年龄17~22岁,采用数字表法随机分为实验组和对照组,各10名。在冬训期间运动量和强度在中到大的20d时间中进行实验。实验组内服课题组根据健脾生血、补肾的治则研制的中药(A药)。药物由人参、黄芪、熟地、阿胶等13味中药组成,制成口服液和胶囊两种剂型,分别在早餐前0.5h和晚餐后2h服用,每次服用口服液20mL(10mL中相当于含生药90g),胶囊9小粒(每粒胶囊0.38g,其中生药含量0.37g,生药量共3.33g)。对照组服用目前国内运动队最常使用的提高血红蛋白中药(B药),由口服液和胶囊铁剂组成,早餐前0.5h服用口服液20mL,晚餐后2h服用胶囊铁剂920mg。两组均连续服药20d。给药全部采取单盲方式。分别在服药前、服药后10d和服药20d,清晨空腹取肘静脉血,作血红蛋白、白细胞、血细胞比容、免疫球蛋白G、免疫球蛋白M测定和运动训练完成量的自我评定和教练员的评定。结果:实验观察期间,因伤病原因,有4名受试者中途退出脱落,未进入结果分析。最后进入结果分析为16名,实验组9名,对照组7名。①实验组服药后10,20d血红蛋白均有升高趋势,但无论是组间,还是组内统计学比较,差异均无显著性意义(P>0.05);白细胞和血细胞比容两组整个实验期间无大的变化。②两组服药后免疫球蛋白G和免疫球蛋白M的变化不明显,仅在实验后20d实验组免疫球蛋白M高于对照组(P<0.05)。③实验组自我评定分有升高趋势,对照组有下降趋势;两组教练员评定分均有升高趋势,但是,除了实验组10d时教练员评定与训练前比较差异有显著性意义外(P<0.05),组间和组内比较差异均无显著性意义(P>0.05)。结论:两组在大运动量、大强度训练后血红蛋白、免疫球蛋白G和免疫球蛋白M均无明显下降的情况发生,维持了原有的水平,中药处方对运动性血红蛋白和免疫功能下降有良好的作用。 相似文献
1000.
Sheng Tu Fudong Hu Wei Cai Liyan Xiao Linlin Zhang Hong Zheng Qiong Jiang Lianglong Chen 《The international journal of cardiovascular imaging》2017,33(5):731-737
There are no previous studies showing how to visualize polymeric bioresorbable scaffolds (BRSs) by micro-computed tomography (mCT). There are no previous studies showing how to visualize polymeric bioresorbable scaffolds (BRSs) by micro-computed tomography (mCT). This study aimed to explore the feasibility of detecting polymeric BRS with 3-dimensional reconstruction of BRS images by contrast-enhanced mCT and to determine the optimal imaging settings. BRSs, made of poly-l-lactic acid (PLLA), were implanted in coronary bifurcation models. Five treatments were conducted to examine an optimal condition for imaging BRSs: Baseline treatment, samples were filled with normal saline and scanned with mCT immediately; Treatment-1, -2, -3 and -4, samples were filled with contrast medium and scanned with mCT immediately and 1, 2 and 3 h thereafter, corresponding to soaking time of contrast medium of 0, 1, 2 and 3 h. Compared to Baseline, mCT scanning completely discriminate the scaffold struts from the vascular lumen immediately after filling the samples with contrast agent but not from the vascular wall until the contrast agent soaking time was more than 2 h (Treatment-3 and -4). By setting 10–15 HU as a cut-point of CT values, the scaffold strut detectable rate at Baseline and Teatment-1, -2, -3 and -4 were 1.23?±?0.31%, 1.65?±?0.26%, 58.14?±?12.84%, 97.97?±?1.43% and 98.90?±?0.38%, respectively (Treatment-3 vs. Treatment-2, p?<?0.01); meanwhile, the success rate of 3D BRS reconstruction with high quality images at Baseline and Teatment-1, -2, -3 and -4 were 1.23%, 1.65%, 58.14%, 97.97% and 98.90%, respectively (Treatment-3 vs. Treatment-2, p?<?0.01). In conclusions, reconstruction of 3D BRS images is technically feasible by contrast-enhanced mCT and soaking time of contrast agent for more than 2 h is necessary for complete separation of scaffold struts from the surrounding structures in the phantom samples. 相似文献