DNA microarray has become an essential medical genetic diagnostic tool for its high-throughput, miniaturization and automation. The design and selection of oligonucleotide probes are critical for preparing gene chips with high quality. Several sets of probe design software have been developed and are available to perform this work now. Every set of the software aims to different target sequences and shows different advantages and limitations. In this article, the research and development of these sets of software are reviewed in line with three main criteria, including specificity, sensitivity and melting temperature (Tm). In addition, based on the experimental results from literatures, these sets of software are classified according to their applications. This review will be helpful for users to choose an appropriate probe-design software. It will also reduce the costs of microarrays, improve the application efficiency of microarrays, and promote both the research and development (R&D) and commercialization of high-performance probe design software.
ObjectiveTo determine the level of CDH1 gene promoter hypermethylation in human gastric carcinoma by establishing MS-PCR method, and analyze retrospectively the possible statistical relationship between CDH1 gene promoter hypermethylation in human gastric carcinoma and HP infection, tumor differentiation, invasion, lymph nodal and distant metastasis, respectively. MethodsThe bisulfite conversion MS-PCR method was adopted to examine the level of CDH1 gene promoter hypermethylation in 40 cases of human gastric carcinoma tissue collected between January 2008 and December 2009. The statistical relationship between CDH1 gene promoter hypermethylation in human gastric carcinoma and HP infection, tumor differentiation, invasion, lymph nodal and distant metastasis were examined respectively with SPSS statistical tools. ResultsThe positive rate of CDH1 gene promoter hypermethylation in gastric carcinomas (67.5%) was higher than that in paired normal gastric mucosae (12.5%), and the difference was significant (P<0.05). In gastric carcinomas, the positive rate of CDH1 gene promoter hypermethylation in well differentiated or moderately differentiated groups (22.2%) was lower than that in poorly differentiated groups (80.6%), and the difference was significant (P<0.05). The positive rate of CDH1 gene promoter hypermethylation in HP positive groups (78.1%) was higher than that in HP negative groups (25.0%), and the difference was significant (P<0.05). ConclusionCDH1 gene promoter hypermethylation may play an important role in the process of tumor carcinogenesis in gastric carcinomas. Meanwhile, the CDH1 gene promoter hypermethylation may lead to poor differentiation in gastric carcinomas. CDH1 gene promoter hypermethylation is related to HP infection in the original gastric carcinomas, which shows that HP may get involved in the process of tumor suppressor gene methylation/inactivation and tumor development process.
ObjectiveTo investigate influence factor of long-term survival of primary colorectal signet-ring cell carcinoma. MethodThe clinical data of 37 patients with primary colorectal signet-ring cell carcinoma from January 1990 to November 2010 in this hospital were analyzed retrospectively. ResultsThe cumulative survival rates of 1-, 2-, 3and 5-year after the initial surgery were 70.3%, 51.4%, 27.0%, and 10.8% respectively. The survival time of 37 patients was 26 months. The results of univariate analysis showed that the TNM stage, T stage, preoperative intestinal obstruction or not, operation mode, and postoperative chemotherapy or not were associated with the survival time of primary colorectal signet-ring cell carcinoma (P < 0.05). The results of multivariable analysis showed that TNM stage, T stage, and preoperative intestinal obstruction or not were the independent factors for the prognosis of patients with primary colorectal signetring cell carcinoma. ConclusionsThe survival rate of patients with primary colorectal signet-ring cell carcinoma is lower. TNM stage, T stage, and preoperative intestinal obstruction or not are independent factors of it. Chemotherapy after operation could prolong survival time of patients with primary colorectal signet-ring cell carcinoma.
ObjectiveTo analyze effect of percutaneous transhepatic choledochus drainage (PTCD) for hilar cholangiocarcinoma. MethodsClinical data of 67 cases of hilar cholangiocarcinoma who treated in our hospital from Jan. 2005 to Dec. 2010 were retrospectively analyzed. ResultsOf the 67 cases, 30 cases were performed PTCD, 20 cases were performed radical surgery after PTCD, and 17 cases were performed palliative surgery after PTCD. There were 59 cases who were followed-up for 3-30 months, and the median time was 9.3 months. The median survival time of patients who underwent PTCD, radical surgery, and palliative surgery were 10.2, 21.4, and 8.9 months respectively. The survival of patients who underwent radical surgery was better than those of underwent PTCD (χ2=13.6, P=0.000 4) and palliative surgery (χ2=15.2, P=0.003 8), and survival of patients who underwent PTCD was better than patients underwent palliative surgery (χ2=5.3, P=0.040 1). ConclusionsPTCD is contribute to preoperative diagnosis and evaluation, in addition, it can reduce unnecessary surgical exploration, guarantee the safety of the radical surgery, and provide follow-up care for palliative operation channel which is favorable for local internal radiation therapy.
ObjectiveTo compare the biomechanical properties between the proximal femoral locking plate and Gamma3 for fixing stable intertrochanteric fracture so as to provide a theoretical basis for selecting internal fixation in the clinical application. MethodsFive pairs of antiseptic femur specimens were selected. Specimens of each pair of matching were randomly divided into groups A and B (n=5). All specimens were made the intertrochanteric fracture of 31A1.1 type according to AO/Association for the Study of Internal Fixation (AO/ASIF) classification. Fracture was fixed with Gamma3 in group A and with proximal femoral locking plate in group B. The axial compression, destruction, and torsion tests were carried out on the mechanical testing machine. ResultsAxial compression test:The load-displacement curve of groups A and B was basically a straight line; axial stiffness of groups A and B was (621.00±36.48) N/mm and (542.55±46.94) N/mm respectively, showing significant difference (t=3.648, P=0.036). Destruction test:The maximum yield load of groups A and B was (4 394.82±450.37) N and (2 987.54±112.14) N respectively, showing significant difference (t=5.433, P=0.032). After loading maximum yield load, femoral fracture occurred again, and internal fixation and bone interface loosening were observed in group A; bending and breaking of proximal locking screw for internal fixation were found in group B, but loosening of internal fixation and bone interface was more obvious in group A than in group B. Torsion test:The torque of specimens in 2 groups increased with the increase of torsion angle (P < 0.05), the torque corresponding to the torsion angle in group B was larger than that in group A, but the difference was not significant (P > 0.05). The torsional stiffness of groups A and B was (1.78±0.16) N·mm/deg and (2.01±0.08) N·mm/deg respectively, showing no significant difference (t=-3.833, P=0.162). ConclusionProximal femoral locking plate and Gamma3 in the treatment of stable intertrochanteric fracture have good biomechanical properties, which can meet the requirements of minimal invasion, strong internal fixation, and early activity.
ObjectiveTo systematically review the efficacy of repetitive transcranial magnetic stimulation (rTMS) on patients with mild cognitive impairment (MCI). MethodsWe searched databases including PubMed, The Cochrane Library (Issue 10, 2015), EMbase, PsycINF, EBSCO, CBM, CNKI, WanFang Data and VIP from inception to October 2015 to collect randomized controlled trials (RCTs) about rTMS for patients with MCI. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies. Then, meta-analysis was performed by using RevMan 5.3 software. ResultsA total of 5 RCTs involving 180 MCI patients were included. The results of meta-analysis showed that, compared with the control group, rTMS treatment could significantly improve the overall cognitive abilities of MCI patients (SMD=2.53, 95% CI 0.91 to 4.16, P=0.002), as well as the single-domain cognitive performances, including tests for episodic memory (MD=0.98, 95% CI 0.24 to 1.72, P=0.01) and verbal fluency (MD=2.08, 95% CI 0.46 to 3.69, P=0.01). rTMS was a well-tolerated therapy, with slightly more adverse events observed than the control group (RD=0.09, 95% CI 0.00 to 0.18, P=0.04), but cases were mainly transient headache, dizziness and scalp pain. ConclusionrTMS may benefit the cognitive abilities of MCI patients. Nevertheless, due to the limited quantity and quality of included studies, large-scale, multicenter, and high quality RCTs are required to verify the conclusion.
Magnetoelastic (ME) sensors, characterized by wireless, passive, low cost and high sensitivity, have widespread applications in various fields. However, its defects of large volume, high power consumption, poor portability and inconveniency for use limit the application prospects of the ME sensors. To solve this problem, the present paper shows a portable, low-power, resonance-type ME sensor detecting system based on STM32. The experimental results indicated that this detecting system allowed the ME sensor to complete the measurement of resonant frequency in different medium and different concentration, with a frequency resolution of less than 1 Hz, and the resonant frequency ratio of ME sensors in different sizes 0.933 8, closing the theoretical value of 0.942 3. Moreover, compared with the traditional impedance analyzer combined detecting system and the existing integrated detecting system, the present system has a power consumption of 0.68 W in operation and of only 2.20 mW in the dormancy mode. Therefore, the system can not only replace the original impedance analyzer combined detecting system, but also significantly improve the power control of the existing integrated detecting system, exhibiting the advantages of higher integration, portable measurement, and fine suitability for long-term monitoring.