超声造影在腹部实脏器外伤诊断及治疗中的价值

超声造影(CEUS)技术的发展和应用显著提高了超声在腹部实脏器外伤的诊断水平,其在腹部实脏器外伤治疗方法筛选及治疗中发挥着重要的作用。根据腹部实脏器外伤治疗的现状,综述CEUS在腹部实脏器外伤的诊断、治疗方法的筛选及治疗中的价值。

Hypermethylated SFRP2 gene in fecal DNA is a high potential biomarker for colorectal cancer noninvasive screening

AIM: To investigate the feasibility of detecting hypermethylated secreted frizzled-related protein 2 (SFRP2) gene in fecal DNA as a non-invasive screening tool for colorectal cancer (CRC). METHODS: Fluorescence-based real-time PCR assay (MethyLight) was performed to analyze SFRP2 gene promoter methylation status in a blinded fashion in tumor tissues and in stool samples taken from 69 CRC patients preoperatively and at the 9th postoperative day,34 patients with adenoma ≥ 1 cm,26 with hyperplastic polyp,and 30 endoscopically normal subjects. Simultaneously the relationship between hypermethylation of SFRP2 gene and clinicopathological features was analyzed. RESULTS: SFRP2 gene was hypermethylated in 91.3% (63/69) CRC,79.4% (27/34) and 53.8% (14/26) adenoma and hyperplastic polyp tissues,and in 87.0% (60/69),61.8% (21/34) and 42.3% (11/26) of corresponding fecal samples,respectively. In contrast,no methylated SFRP2 gene was detected in mucosal tissues of normal controls,while two cases of matched fecal samples from normal controls were detected with hypermethylated SFRP2. A significant decrease (P < 0.001) in the rate of hypermethylated SFRP2 gene was detected in the postoperative (8.7%,6/69) fecal samples as compared with the preoperative fecal samples (87%,60/69) of CRC patients. Moreover,no significant associations were observed between SFRP2 hypermethylation and clinicopathological features including sex,age,tumor stage,site,lymph node status and histological grade,etc. CONCLUSION: Hypermethylation of SFRP2 gene in fecal DNA is a novel molecular biomarker of CRC and carries a high potential for the remote detection of CRC and premalignant lesions as noninvasive screening method.

Pancreatic ductal adenocarcinoma screening:New perspectives

Pancreatic ductal adenocarcinoma accounts for more than 90% of all pancreatic cancers and its incidence has increased significantly worldwide.Patients with pancreatic ductal adenocarcinoma have a poor outcome and more than 95% of the people affected die from the disease within 12 mo after diagnosis.Surgery is the first-line treatment in the case of resectable neoplasm,but only 20% of patients are candidates for this approach.One of the reasons there are few candidates for surgery is that,during the early phases of the disease,the symptoms are poor or non-specific.Early diagnosis is of crucial importance to improve patient outcome;therefore,we are looking for a good screening test.The screening test must identify the disease in an early stage in order to be effective;having said this,a need exists to introduce the concept of "early" ductal adenocarcinoma.It has been reported that at least five additional years after the occurrence of the initiating mutation are required for the acquisition of metastatic ability of pancreatic adenocarcinoma and patients die an average of two years thereafter.We have reviewed the most recent literature in order to evaluate the present and future perspectives of screening programs of this deadly disease.

Strategies for Antiviral Screening Targeting Early Steps of Virus Infection

Viral infection begins with the entry of the virus into the host target cell and initiates replication. For this reason, the virus entry machinery is an excellent target for antiviral therapeutics. In general, a virus life cycle includes several major steps: cell-surface attachment, entry, replication, assembly, and egress, while some viruses involve another stage called latency. The early steps of the virus life cycle include virus attachment, receptor binding, and entry. These steps involve the initial interactions between a virus and the host cell and thus are major determinants of the tropism of the virus infection, the nature of the virus replication, and the diseases resulting from the infection. Owing to the pathological importance of these early steps in the progress of viral infectious diseases, the development of inhibitors against these steps has been the focus of the pharmaceutical industry. In this review, Herpes Simplex Virus (HSV), Hepatitis C Virus (HCV), and Human Enterovirus 71 (EV71) were used as representatives of enveloped DNA, enveloped RNA, and non-enveloped viruses, respectively. The current mechanistic understanding of their attachment and entry, and the strategies for antagonist screenings are summarized herein.

Application of phage display technology in targeted therapy of breast cancer

Phage display is a technology of gene expression and screening, it is widely used in the fields of defining antigen epitopes, signal transduction, genetic treatment, parasites research and tumor targeted therapy. Breast cancer is the most common cancer in women, we can obtain peptides specially associated with breast cancer by using phage display technology, and this method has great potential in early diagnosis of breast cancer and development new targeted drugs.

无义突变型荧光素酶稳定表达细胞株的建立

目的:建立稳定表达含无义突变位点荧光素酶的细胞株,用以筛选新的无义突变通读剂。方法:酶切质粒p GL4-WT和p GL4-MUT,得到野生型和无义突变荧光素酶编码c DNA,分别插入到慢病毒载体p LVX-IRES-Neo多克隆位点。酶切及PCR鉴定后,将重组载体包装成慢病毒颗粒,感染HEK 293细胞,单克隆细胞抗性筛选获得稳定细胞株,提取总RNA,经逆转录PCR方法验证荧光素酶m RNA表达。最后用已知阳性无义突变通读剂G 418处理细胞,Western blot方法检测处理前后荧光素酶蛋白表达水平,同时分析荧光素酶活性。结果:经酶切获得2.7 kb长野生型和无义突变荧光素酶编码c DNA,与p LVX-IRES-Neo连接获得重组慢病毒载体p LVX-WT、p LVX-MUT,EcoRⅠ单酶切、NheⅠ与BamHⅠ双酶切结果证明序列正确插入,PCR也扩增出目的片段;稳定感染慢病毒的HEK293WT和HEK293MUT细胞经逆转录PCR方法成功检测到荧光素酶m RNA表达;阳性通读剂G 418处理细胞后发现,HEK293WT细胞在处理前后均表达荧光素酶蛋白,荧光素酶活性也基本相同,而HEK293MUT细胞在处理前不表达荧光素酶蛋白,无荧光素酶活性,处理后恢复了部分荧光素酶蛋白表达,其荧光素酶活性相当于HEK293WT细胞的20%。结论:成功建立了稳定表达无义突变荧光素酶的细胞株,可用于筛选新的无义突变通读剂。