OBJECTIVETo evaluate the application of low-dose CT enterography with adaptive iterative dose reduction(AIDR) technique in diagnosing Crohn's disease.

METHODSRetrospective analysis was performed on 26 patients diagnosed as Crohn's disease by the multidisciplinary team in our hospital. Low-dose CT enterography with 640-slice MDCT was performed on these 26 patients using adaptive iterative dose reduction(AIDR) technique. Characteristics of Crohn's disease in CT enterography images were independently analyzed by two radiologists who were experienced in Crohn's disease with calculating the total radiation dosage.

RESULTSThe radiation dosage of 26 patients ranged from 5.58 to 12.90 [mean (9.00±2.00)] mSv, which was lower than conventional scan (around 15 mSv) known from the literatures. According to the images of CT enterography of 26 cases, bowel wall thickening with abnormal enhancement and lymphadenectasis were found in 25 cases with total 109 segmental bowel wall thickening. Among 25 thickening cases, enterostenosis was found in 16 cases, stratification enhancement in 12 cases and comb sign in 14 cases. Besides, it was found that 8 cases with hyperdense fat on the mesenteric side, 7 cases with intestinal fistula, 6 cases with abdominal cavity abscess, and 3 cases with anal fistula.

CONCLUSIONCT enterography of Crohn's disease with adaptive iterative dose reduction technique is an effective method to evaluate Crohn's disease without compromising image quality with reduced radiation dosage.

Crohn Disease ; diagnostic imaging ; Humans ; Intestinal Fistula ; Radiation Dosage ; Rectal Fistula ; Retrospective Studies ; Tomography, X-Ray Computed ; methods

Objective To investigate the clinical and pathological features of patients with esophageal neuroendocrine carcinoma (ENEC).Methods From January 2011 to November 2018,107 patients with pathologically confirmed ENEC were enrolled at the First Affiliated Hospital of Zhengzhou University.The clinical manifestation,tumor location,tumor size,clinical pathological classification and immunohistochemical markers were analyzed.Statistical description was used for measurement data analysis,and chi-square test was performed for classification data analysis.Results Among 107 patients with ENEC,feeling obstruction during eating was the most common initial symptom,accounting for 63.6％ (68/107);followed by chest and back pain,accounting for 13.1％ (14/107).About 60.7％ (65/107) patients were diagnosed by biopsy under endoscopy and 39.3％ (42/107) patients were confirmed by pathological diagnosis after surgery.The proportion of tumor located in the upper thoracic esophagus and middle and lower thoracic segments was 13.1％ (14/107),45.8％ (49/107) and 41.1％ (44/107),respectively.The length of tumor was 0.7 cm to 9.0 cm,and the median was 2.5 cm.Among them,57.0％ (61/107) were less than 2.5 cm and 43.0％ (46/107) were over 2.5 cm.Among 107 patients,50 (46.7％) patients were ulcerative type,32 (29.9％) patients were medullary type,16 (15.0％) patients were mushroom type and nine (8.4％) patients were protrude type.Among 107 patients,96 (89.7％) patients were pure neuroendocrine carcinoma (P-NEC;including 95 small cell types,one large cell type);11 (10.3％) patients were mixed neuroendocrine carcinoma (M-NEC;including nine small cell carcinoma mixed with squamous cell carcinoma,two small cell carcinoma mixed with adenocarcinoma).The positive rates of synaptophysin,CD56 and chromogranin A were 99.0％ (104/105),98.0％ (100/102) and 31.5％ (17/54),respectively.Ki-67 proliferation index of 47.7％ tumors (51/107) was between 90％ and 100％.P-NEC with the maximum diameter over 2.5 cm accounting for 42.1％ (45/107),and M-NEC accounting for 0.9％ (1/107).The maximum diameter of P-NEC group was larger than that of M-NEC group,and the difference was statistically significant (x2 =4.311,P =0.038).Conclusions ENEC is a kind of highly aggressive malignant tumor with nonspecific manifestations.The diagnosis mainly depends on histopathology and immunohistochemistry.

Objective: To study the effect of LncRNA CRNDE on radiosensitivity of colorectal cells and underlying mechanism. Methods: Colorectal cancer HT-29 cells were transfected with CRNDE shRNA and the interference efficiency was determined by Real time PCR. HT-29 cells transfected with CRNDE shRNA or co-transfected with CRNDE shRNA and miR-384 inhibitor were irradiated at 8 Gy dose, then cell proliferation and apoptosis were detected by MTT and flow cytometry assay, respectively, and cell radiosensitivity was evaluated by cloning assay. It was predicted by a bioinformatics software that CRNDE and miR-384 have complementary binding sites, and this was identified by a luciferase reporting system. Results: CRNDE shRNA reduced the expression of CRNDE in HT-29 cells(1.00±0.08 vs. 0.42±0.06, t=10.051, P<0.05). Both CRNDE shRNA and radiation inhibited the proliferation and induced apoptosis of HT-29 cells, and their combination treatment had synergistic effect in apoptosis induction [Apoptosis rates: (2.27±0.13)%, (23.58±2.35)%, (26.91±2.81)%, (36.84±3.24)%, F=24.660, P<0.05; A values: 0.45±0.06, 0.30±0.02, 0.28±0.03, 0.20±0.02, F=106.207, P<0.05]. Transfection of CRNDE shRNA increased the radiosensitivity of HT-29 cells with a radiosensitization ratio of 1.374. CRNDE negatively regulated the expression of its target miR-384. The miR-384 inhibitor antagonized the effect of CRNDE shRNA on proliferation inhibition and apoptosis promotion of radiation-treated colorectal cancer cells. Conclusions Down-regulation of LncRNA expression enhances the radiosensitivity of colorectal cancer cells by regulating miR-384 expression.