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101.
水溶性量子点荧光探针用于胃癌细胞相关抗原CA242的检测 总被引:5,自引:0,他引:5
基于量子点荧光探针对胃癌细胞相关抗原CA242进行了检测。首先在水溶液中直接合成性能优良的量子点荧光纳米颗粒,并在其表面成功修饰了羊抗小鼠IgG和聚乙二醇,制得功能化的水溶性量子点荧光探针,并利用探针对胃癌细胞相关抗原CA242进行检测,进一步与传统的基于荧光染料标记的免疫荧光分析方法进行了比较。实验结果表明:该功能化的探针能够有效地识别胃癌细胞相关抗原CA242,并且在光稳定性和灵敏度方面都较传统的基于荧光染料标记的免疫荧光分析方法有明显的改善,从而为CA242的相关检测以及胃癌的诊断与愈后判断提供了新的方法。 相似文献
102.
陈伯扬 《广东微量元素科学》2008,15(3):15-18
从福建省胃癌高(长乐市)、低发区(福安市)的土壤、水体及人体血清、头发、尿液采集的材料入手,分析了砷元素与恶性肿瘤关系。结果表明,胃癌低发区土壤、饮用水和人头发砷含量反比高发区高。可见在正常情况下砷不致癌,适量砷可抑制癌症。 相似文献
103.
It is recognized that minor dietary components polyphenols have anticancer effects on digestive tract, lung, leukemia, and other cancers, while polyphenols also can covalently or noncovalently interact with major dietary components proteins such as casein, soybean proteins, whey proteins, and bovine serum albumin. Thus, whether the noncovalent interaction between the molecules of two polyphenols (quercetin and fisetin) and two proteins (bovine serum albumin and casein) has positive or negative impact on anticancer activities of the polyphenols against human gastric adenocarcinoma AGS cells was assessed in this study. The two polyphenols had obvious anticancer activities to the cells, because dose levels as low as 20–160 μmol/L caused reduced cell viability of 30.0–69.4% (quercetin) and 24.6–63.1% (fisetin) (using a cell treatment time of 24 h), or 9.9–48.6% (quercetin) and 6.4–29.9% (fisetin) (using a cell treatment time of 48 h). However, the cell treatments by the polyphenols in the presence of the two proteins mostly caused lower polyphenol activity toward the cells, compared with those treatments by the polyphenols in the absence of the proteins. Specifically, the presence of the proteins led to reduced growth inhibition in the cells, because higher cell viability of 33.2–86.7% (quercetin) and 29.1–77.7% (fisetin) at 24 h, or 14.1–66.8% (quercetin) and 7.9–59.0% (fisetin) at 48 h, were measured in these treated cells. The two coexisting proteins also yielded the polyphenol-treated cells with less mitochondrial membrane potential loss, less formation of reactive oxygen species, and decreased cell apoptosis. Thus, it is highlighted that the noncovalent interaction between dietary polyphenols and proteins resulted in weakened anticancer ability for the polyphenols to the gastric cancer cells. 相似文献
104.
Background: A gastric cancer (GC) diagnosis relies on histopathology. Endoscopy rates are increasing. Helicobacter pylori infection is a major GC risk factor. In an effort to elucidate abundant blood biomarkers, and potentially reduce the number of diagnostic surgical interventions, we investigated sera and biopsies from a cohort of 219 H. pylori positive and negative patients diagnosed with GC, gastritis, and ulcers. This allowed the comparative investigation of the different gastroduodenal diseases, and the exclusion of protein changes resulting from bacterial infection or inflammation of the gastric mucosa when searching for GC-dependent proteins. Methods: High-definition mass spectrometry-based expression analysis of tryptically digested proteins was performed, followed by multivariate statistical and network analyses for the different disease groups, with respect to H. pylori infection status. Significantly regulated proteins differing more than two-fold between groups were shortlisted, and their role in gastritis and GC discussed. Results: We present data of comparative protein analyses of biopsies and sera from patients suffering from mild to advanced gastritis, ulcers, and early to advanced GC, in conjunction with a wealth of metadata, clinical information, histopathological evaluation, and H. pylori infection status. We used samples from pre-malignant stages to extract prospective serum markers for early-stage GC, and present a 29-protein marker panel containing, amongst others, integrin β-6 and glutathione peroxidase. Furthermore, ten serum markers specific for advanced GC, independent of H. pylori infection, are provided. They include CRP, protein S100A9, and kallistatin. The majority of these proteins were previously discussed in the context of cancer or GC. In addition, we detected hypoalbuminemia and increased fibrinogen serum levels in gastritis. Conclusion: Two protein panels were suggested for the development of multiplex tests for GC serum diagnostics. For most of the elements contained in these panels, individual commercial tests are available. Thus, we envision the design of multi-protein assays, incorporating several to all of the panel members, in order to gain a level of specificity that cannot be achieved by testing a single protein alone. As their development and validation will take time, gastritis diagnosis based on the fibrinogen to albumin serum ratio may be a quick way forward. Its determination at the primary/secondary care level for early diagnosis could significantly reduce the number of referrals to endoscopy. Preventive measures are in high demand. The protein marker panels presented in this work will contribute to improved GC diagnostics, once they have been transferred from a research result to a practical tool. 相似文献
105.
Yixin Liu Yuheng Zhao Yue Zhuo Yuwen Li Jiaxin Meng Yilin Wang Houhua Li 《Molecules (Basel, Switzerland)》2022,27(13)
Red Malus ‘Royalty’ fruits are rich in anthocyanins. This study aimed to obtain the optimal parameters for the extraction and separation of anthocyanins from Malus ‘Royalty’ fruits and to evaluate the inhibitory effect of the enriched anthocyanin fraction on gastric cancer cells. Ultrasonic-assisted extraction was used for the extraction of the anthocyanins of Malus ‘Royalty’ fruit, and the extraction results showed that the optimum parameters were an extraction temperature of 20 °C, a solid–liquid ratio of 1:6 (g/mL), ethanol and formic acid contents of 70% and 0.4%, respectively, an extraction time of 40 min, and an ultrasonic power of 300 W. The optimum extraction parameters to achieve the highest anthocyanin yield by a single-factor experiment coupled with response surface methodology were identified. The separation results showed that the AB-8 macroporous resin was a better purifying material, with 60% ethanol as an adsorbent, and the adsorption–desorption equilibrium times were 6 h and 1 h, respectively. Cyanidin-3-galactoside was the main body composition separation of anthocyanins by a high-performance liquid chromatography-diode array detector. The antitumor activity results showed that the anthocyanins of Malus ‘Royalty’ fruits have a significant inhibitory effect on the gastric cancer cell line BGC-803. The in vitro cell viability test of CCK-8 showed that the inhibitory effect on tumor cells was more significant with the increased anthocyanin concentration, with a half maximal inhibitory concentration (IC50) value of 105.5 μg/mL. The cell morphology was observed by an inverted microscope, and it was found that the backbone of BGC-803 treated with a high concentration of anthocyanins was disintegrated and the nucleoplasm was concentrated. The mechanism of apoptosis was analyzed by Western blotting, and the results showed that with increasing anthocyanin concentration in the medium, the expression levels of the proapoptotic proteins Bax and Bak increased, and the expression levels of the antiapoptotic proteins Bcl-2 and Bcl-xL decreased, which coordinated the regulation of cell apoptosis. This research suggests that the enriched anthocyanin fraction from Malus ‘Royalty’ fruits have potential antitumor and adjuvant therapeutic effects on gastric cancer. 相似文献
106.
将2017年1月至2018年12月于西宁市第二人民医院行新辅助治疗的72例胃癌患者纳入研究,同时给予患者超声造影(contrast-enhanced ultrasonography,CEUS)检查及磁共振成像(magnetic resonance imaging, MRI)增强扫描,比较并分析二者对治疗后分期及肿瘤周围侵犯情况的检查结果,以探究CEUS在评估胃癌新辅助治疗后分期及侵犯情况方面与MRI的一致性。研究结果显示,MRI和CEUS评估胃癌T分期的诊断一致率为91.67%,具有较高一致性;CEUS和MRI评估病灶的左右径、纵轴直径和前后径具有较好的一致性,且两者无明显差异;CEUS与MRI评估其侵袭横结肠及其系膜、肝/脾、十二指肠/胰腺的诊断,具有较高的一致性。本研究证实,CEUS与MRI在评估胃癌T分期、病灶大小及周围组织侵犯情况时结果基本一致。 相似文献
107.
108.
Elena Olaret Jana Ghitman Horia Iovu Andrada Serafim Izabela‐Cristina Stancu 《先进技术聚合物》2020,31(4):645-653
Although widely used as implantable materials due to their mechanical properties, metal devices show several disadvantages, such as the lack of cellular binding sites, antibacterial properties, or lubricant properties. To this end, the development of engineered surfaces through protein coatings has been largely investigated. Due to their natural origin and complex structure which allows the formation of hydrogels, mucins have been proposed and investigated as effective coatings for metallic implants. The present study evaluates the ability of porcine gastric mucin (PGM) to form stable coatings on a model metal surface, using three buffers with different pH values, ranging from acid to alkaline, as dispersion media. Considering its large number of hydroxyl groups and its ability to form hydrogen bonds with the protein, tannic acid (TA) was used as cross‐linker. In addition to coatings' thickness and elasticity assessed through Quartz Crystal Microbalance with Dissipation monitoring (QCM‐D), the study also evaluates the interactions between PGM and TA at various pH values of the dispersion media through DLS. The corroborated results show that the neutral pH allows the best interactions between PGM and TA leading to the formation of a stable, less elastic coating when compared with that obtained using as dispersion media the other two investigated buffers. Moreover, the hydrophilicity and mechanical properties of the dried coatings were assessed through contact angle measurements and nanoindentation, respectively. 相似文献
109.
Masahiro ASAKA Katsuhiro MABE 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2014,90(7):251-258
In Japan, efforts have been directed toward improving the detection of early gastric cancer by double contrast radiography and endoscopy, since early cancer has a good prognosis, resulting in Japan having the world’s best diagnostic system for early gastric cancer. The 5-year survival rate of gastric cancer patients in Japan is much higher than in Western countries by the development of endoscopic treatment for early gastric cancer. In February 2013, Japanese national health insurance cover for H. pylori eradication therapy was expanded to patients with H. pylori-associated gastritis, a type of chronic gastritis. H. pylori-associated gastritis causes gastric and duodenal ulcers and gastric polyps, therefore, providing treatment for this gastritis is likely to substantially decrease the prevalence of both gastric and duodenal ulcer and gastric cancer. Patients with gastritis are tested for H. pylori infection and those who are positive receive eradication therapy followed by periodic endoscopic surveillance. If such an approach is pursued further in Japan, gastric cancer deaths will show a dramatic decline after 10–20 years. 相似文献
110.
Miki K 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2011,87(7):405-414
The current status of screening for gastric cancer-risk (gastritis A, B, C, D) method using combined assay for serum anti-Helicobacter pylori (Hp) IgG antibody and serum pepsinogen (PG) levels, "ABC method", was reviewed and the latest results of our ongoing trial are reported. It was performed using the following strategy: Subjects were classified into 1 of 4 risk groups based on the results of the two serologic tests, anti-Hp IgG antibody titers and the PG I and II levels: Group A [Hp(-)PG(-)], infection-free subjects; Group B [Hp(+)PG(-)], chronic atrophic gastritis (CAG) free or mild; Group C [Hp(+)PG(+)], CAG; Group D [Hp(-)PG(+)]), severe CAG with extensive intestinal metaplasia. Continuous endoscopic follow-up examinations are required to detect early stages of gastric cancer. Asymptomatic Group A, which accounts for 50-80% of all the subjects may be excluded from the secondary endoscopic examination, from the viewpoint of efficiency. Hp-infected subjects should be administered eradication treatment aimed at the prevention of gastric cancer. 相似文献