ABSTRACT
X-ray micro-computed tomography (CT) is an important tool for high-resolution three-dimensional imaging. But one limitation of micro-CT is the compromise between resolution and fields of view (FOV). In this paper, we develop an x-rays dual-FOV optical coupling detection (DFOCD) system for global imaging with high-resolution region of interest (ROI). In DFOCD system, the beam splitter separates lights to form two sub-optical paths, two objectives with different FOV and magnification are used in the two sub-optical paths for dual-FOV imaging. Then a data fusion method is proposed to register and fuse dual-FOV data. Reconstructed images are obtained based on back projection filtering algorithm using fusion data. Dual-FOV data are collected simultaneously in DFOCD system, which precludes artifacts in fusion images from phantom movement or changes in two acquisitions on common micro-CT, and also saves scanning time. Simulation and experimental results show that details in ROI and global morphology of phantoms are correctly reconstructed. Bright ring artifacts of ROI caused by truncated data are corrected in reconstruction images. Therefore, global imaging with high-resolution ROI of samples can be obtained by single scan experiment using DFOCD system and data fusion method, which is expected to expand the application of micro-CT.
ABSTRACT
ObjectiveTo investigate the relationship between tumor necrosis factor (TNF) α308,TNF-β252 genotypes and serum TNF-α and TNF-β levels in patients with gastric cancer (GC).MethodsA total of 57 pathological diagnosed GC patients were collected,of which 49 cases were from Zhongnan Hospital of Wuhan University and 8 cases were from Tumor Hospital of Hubei Province.Another 18 age and sex matched healthy controls were enrolled at the same time.The TNF-α308 and TNF -β252 polymorphism was genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).The serum TNF-α and TNF-β levels of 57 GC patients and 18 healthy controls were measured by ELISA.The difference of TNF serum level in different TNF genotypes of GC and the difference between GC patients and the healthy controls was analyzed.Its relationship with clinical pathological characters was also analyzed.Results With TNF-α308 genotype,GA were 6 cases and GG were 51 cases.With TNF-β252 genotype,GG were 17 cases,GA and AA each were 20 cases.The serum TNF-α level of GC patients was significant higher than that of healthy controls (median 445 × 10-3 μg/L vs 5 × 10-3 μg/L,P＜0.05),and the serum level of each TNF-α308 andTNF-β 252 genotypes was significant higher than that of healthy controls (P＜0.05).However there was no statistical significance in TNF -β level compared with healthy controls (P＞0.05).In addition,the serum TNF-α levels of the TNF-α308G/TNF-β252G and TNF-α308G/TNF β252A haplotypes in GC patients were significant higher than those of the healthy controls (P＜0.05),and the increase like serum TNF-α level was associated with the patients'age and lymph node metastasis (P＜0.05).The TNF-β level in patients with TNF-α308A and TNF-β252G high-risk haplotypes showed a significant relation with smoking history (P＜ 0.05). Conclusions Serum TNF-α level of GC patients was significantly higher,however there was no significant association between the increase and TNF-α308 and TNF-β252 genotypes.The serum TNF-α levels of TNF-α308G/TNF-β252G and TNF-α308G/TNF-β252A haplotypes in GC patients were significant higher,and associated with the patients'age and lympb node metastasis.It was indicated that TNF haplotypes may have certain impact on the TNF expression and clinical subtypes in GC.
