ABSTRACT
Objective To analyze the CT and MRI characteristics of the pineal region tumors (PRTs) to improve the accuracy of diagnosis and differential diagnosis.Methods The MRI and CT findings of 28 patients with PRTs proved by operation and pathology were retrospectively analyzed.Eight of them were performed preoperative 1H-MRS and DWI examination and thier data were analyzed too.Results of these 28 patients,11 were diagnosed as having germinoma,4 teratoma,3 astrocytoma,3 meningioma,2 pinealocytoma and 1 epidermoid cyst,1 pineoblastoma,1 hamartoma and 1 dermoidcyst.The main imaging characteristics were cystic tumors in the pineal region,variational density/signal intensity with few tumors having their specified morphology,density/signal intensity and enhancement style.The germinomas and the pineoblastomas were mainly homogeneous solid masses with symmetrical density/signal.The astrocytoma was cystic-solid,mostly,with changing shapes and odds density/signal.The mature teratoma showed blending density/signal.The 1H-MRS showed typical high Cho peak and low NAA peak in the astrocytoma; no NAA peak was found in the meningeoma; high Cho peak and no Lip peak were found in the pineoblastoma; the germinoma was noted having Lip peak.Conclusion Observation on the changes of the morphologic features,density/signal intensity and enhancement style can help in the differential diagnosis of PRTs.DWI and 1H-MRS examinations can improve the accuracy of differential diagnosis to some extent,but some PRTs remain to be non-differentiable.
ABSTRACT
Objective To establish real-time PCR with SYBR Green Ⅰ for quantification the gene of survivin.Methods The components and conditions of PCR system were optimally determined by fluorescence intensity,cycle threshold(Ct),melting curve,coefficiency and slope of the standard curve.The means to eliminate the contaminating fluorescence of primer-dimers and the mode for Ct value determination were also optimized.Using the developed PCR system,we quantificated the survivin gene in 43 patients with gastric carcinoma.Results The optimized condition for PCR amplification of survivin were 2 mmol/L of MgCl_2,2.5 U/100 ?l of Taq DNA polymerase,0.2 ?mol/L of primers,and the optimized annealing temperatures for PCR were 58℃.The influence of primer dimmer can be eliminated by setting the fluorescence collecting temperature below the Tm of the specific amplicon by 2℃.The second derivative maximum mode,instead of fit point mode,was a feasible method to determine the Ct value for quantification.The sensitivity of this method was 10 copies/?l,and a good linearity was found from 10~1 to 10~4 copies/?l(r = 0.999 7).The inter-experimental coefficient of variation was 1.13%-1.91%,whereas the coefficient of variation between runs was 3.31%-4.50%.Using the optimized PCR system,we quantificated the gene of survivin,the result indicated that survivin gene was amplified in 13.9% of gastric carcinomas.Conclusions The optimal real-time PCR with SYBR Green Ⅰ,as a cost-effective and feasible DNA quantitative method,is fit for quantification of the survivin with satisfactory repeatability and high sensitivity.