Objective To analyze the value of conventional T2WI combining with breath-hold Cartesian VIBE sequence, and compared with Blade combining with breath-free radial VIBE sequences in pre-operative T staging of potentiallly resectable esophageal carcinoma. Methods Sixty-five cases of esophageal carcinoma were concluded prospectively. All patients had received pathological examination of gastroscope biopsy before MRI. Patients received MR examination, including T2WI, breath-hold VIBE, Blade, and breath-free radial VIBE sequences. Two radiologists with more than five years experiences in the diagnosis of chest, performed T staging in MRIby referring to the the 7th edition of UICC-AJCC TNM classification. The results of MRI T staging and the postoperative pathological T staging were analyzed byχ2 test. Results Sixty-five patients were included. Diagnostic coincidence rates of the preoperative T staging by using conventional T2WI combining with breath-hold Cartesian VIBE sequences and Blade combining with breath-free radial VIBE sequences were 51%(33/65) and 88%(57/65) ,with 32 and 8 cases overstaging or understaging respectively, and the statistical differences were significant(χ2=20.80, P<0.05). The former diagnostic accuracy of esophageal carcinoma in situ, muscularis violation and esophageal fiber membrane were 42%(8/19), 54%(14/26), 55%(11/20), and the latter were 89%(17/19), 88%(23/26), and 85%(17/20). Conclusions Diagnostic coincidence rate of the preoperative T staging by using Blade combining with breath-free radial VIBE sequences is much higher than conventional T2WI combining with breath-hold Cartesian VIBE sequences. Blade combining with breath-free radial VIBE sequences could be used as non-invasive imaging method in preoperative T staging of potentially resectable esophageal carcinoma.

Carbapenem-resistant Klebsiella pneumoniae (CRKP) leads to high mortality of infected patients. How to deal with CRKP is an urgent problem in clinical practice, and it is imperative to carry out researchon carbapenem resistance mechanism of CRKP. The two-component systems (TCSs) areassociated with the development of drug resistance in a variety of bacteria, and TCSs were expected to be important therapeutic targets for CRKP. Therefore, this article reviewed the mechanisms of TCSs in the regulation of CRKP from the following several aspects: common mechanisms of carbapenem resistance of CRKP, research progress in drug resistance of TCSs, relationships between Klebsiella pneumoniae and TCSs, and so on. It may provide some research ideas for future research and the references for clinical diagnosis and treatment.