Objective To study the effects of gantry rotation time on image quality in 64-slice spiral CT. Methods Using the same CT technique and body mode as those used for 64-slice spiral CT, delta phantom was firstly layed on the isocenter, then scanned and reconstructed with SOMATOM Sensation 64-slice spiral CT. Slice sensitivity profile(SSP) was measured from which modulation transfer function (MTF) were got by Fourier transfer. The Catphan500 phantom was layed on the table, then scanned and reconstructed with SOMATOM Sensation 64-slice spiral CT. The maximum linepair and minimum size of the targets visualized. Results The MTF curve was nearly overlapped on 0.5 s and 1.0 s gantry rotation time, the values of 5% MTF were 11.3 LP/cm and 11.9 LP/cm. Their spatial resolution and low contrast resolution were completely identical.Conclusion The image quality is no distinction on 0.5 s group and 1.0 s group of gantry rotation time. In order to shorten the scan time and eliminate the breath defect, we suggest that the 0.5 s gantry rotation time be used routinely at body spiral scan mode.

Objective To observe the expression of heat shock protein 70 (HSP70) in lung of rats after paraquat (PQ) poisoning and to investigate the therapeutic effects of ulinastatin. Method Seventy-two adult healthy SD rats were randomly(random number) divided into control group (group A, n = 24), poisoning group (group B, n =24) and ulinastatin group (group C, n =24). The rat models of acute PQ poisoning were established by intra-gastric administration of 80 mg/kg PQ to rats of group B and group C, and the rats of group C were intra-peritoneally injected with 100 000 IU/kg ulinastatin 30 minutes after poisoning. The expression of HSP70 in lung tissue was observed, and W/D and histopathological changes in lung tissue were compared 12 h,24 h,48 h and 72 hours after poisoning. The expression of HSP70 in lung tissue was assayed by using RT-PCR. All quantitative data were processed with one-way analysis of variance to compare multiple sample means. Results Compared with group A, the expression of HSP70 in the lung of rats in group B and group C increased significantly at all intervals ( P ＜ 0.05). The pathological changes in lung tissue of rats with PQ poisoning showed mainly congestion,leukocytes infiltration and local hemorrhage, and the pathological changes in lung tissue of group C were significantly lessened. Conclusions Ulinastatin may ameliorate the acute lung injury to a certain extent after PQ poisoning in rats by enhancing the expression of HSP70.

Objective:To develop an automated landmark location system applicable to the case of landmark missing.Methods:Four and eighty-one lateral cephalograms, which contained 240 males and 241 females, with an average age of (24.5±5.6) years, taken from January 2015 to January 2021 in the Department of Orthodontics, Capital Medical University School of Stomatology, and met the inclusion criteria were collected. Five postgraduate orthodontic students were the annotators to manually locate 61 possible landmarks in 481 lateral cephalograms. Two assistant professors in the department as reviewers performed calibration. Two professors as arbitrators, made final decision. Data sets were established (341 were used as training set, 40 as validation set, and 100 as test set). In this paper, an automatic landmarks identification and location model based on convolutional neural networks (CNN), CephaNET, was developed. The model was trained by feeding the original image into the feature extraction module and convolutional pose machine (CPM) module to locate landmarks with high accuracy using deep supervision. Training set was enhanced to 1 684 images by histogram equalization, cropping, and adjustment of brightness. The model was trained to compare the Gaussian heat maps output from the network with the set threshold to identify landmark missing cases. Test set of 100 lateral cephalograms was used to test the accuracy of the model. The evaluation criteria used were success detection rate of missing landmark, mean radial error (MRE) and success detection rate (SDR) in the range of 2.0, 2.5, 3.0, 3.5 and 4.0 mm.Results:The model identified and located 61 commonly used landmarks in 0.13 seconds on average. It had an average accuracy of 93.5% in identifying missing landmarks. The MRE of our testing set was (1.19±0.91) mm. SDR of 2.0, 2.5, 3.0, 3.5 and 4.0 mm were 85.4%, 90.2%, 93.5%, 95.4%, 97.0% respectively.Conclusions:The model proposed in this paper could adapt to the absence of landmark in lateral cephalograms and locate 61 commonly used landmarks with high accuracy to meet the requirements of different cephalometric analysis methods.

Objective:To evaluate the effect of short-term very low-calorie restriction(VLCR) on glycemic control in overweight/obese patients with type 2 diabetes, and to explore mechanisms through identifying markers of gut microbiota.Methods:This trial was conducted in 14 adult overweight/obese patients with type 2 diabetes. They received VLCR for 9 days in the hospital(calorie intake 300-600 kcal/d). Before and after VLCR, body weight(BW), waist circumference(WC), blood pressure(BP), and heart rate(HR) were measured, and body mass index(BMI) was calculated according to their height and weight. Fasting blood glucose(FBG), 2 h postprandial blood glucose(2hPBG), fasting insulin(FINS), triglycerides(TG), total cholesterol(TC), high-density lipoprotein-cholesterol(HDL-C), and low-density lipoprotein-cholesterol(LDL-C) were determined, and yielded the homeostasis model assessment for insulin resistance(HOMA-IR). Additional lab tests such as liver and kidney function and electrolytes were performed. The estimated glomerular filtration rate(eGFR) was calculated to evaluate renal function. All data were analyzed using the SPSS Sample Power software. Feces samples were collected before and after VLCR. Fecal samples were tested for microbial diversity using 16S rDNA technology. Professional software was used to analyze the differences of gut microbiota in feces before and after VLCR.Results:After 9 days of VLCR, BW, BMI, WC, BP, HR, FBG, 2hPBG, FINS, HOMA-IR, alkaline phosphatase, TG, and blood urea nitrogen of 14 overweight/obese patients with type 2 diabetes were significantly reduced( P<0.05). No effect was seen on serum alanine aminotransferase, aspartate amino transferase, gamma glutamyl transferase, TC, HDL-C, LDL-C, creatinine, eGFR, uric acid, albumin, calcium, and phosphorus( P>0.05). The gut microbiota diversity did not differ before and after VLCR. The abundance of Bacteroidetes increased significantly, and the Firmicutes/Bacteroidetes ratio decreased from 11.79 to 4.20. Between groups analysis showed the abundance of Parabacteroides distasonis increased significantly after VLCR. Conclusion:VLCR can improve body weight and glucose and lipid metabolism in overweight/obese patients with type 2 diabetes, with no serious adverse events. Parabacteroides distasonis may be a marker of VLCR.

Objective: To investigate the efficacy and safety of the new investigational drug pegylated interferon α-2b (Peg-IFN-α-2b) (Y shape, 40 kD) injection (180 µg/week) combined with ribavirin in the treatment of patients with genotype 1/6 chronic hepatitis C (CHC), with standard-dose Peg-IFN-α-2a combined with ribavirin as a positive control. Methods: A multicenter, randomized, open-label, and positive-controlled phase III clinical trial was performed. Eligible patients with genotype 1/6 CHC were screened out and randomly divided into Peg-IFN-α-2b(Y shape, 40kD) group and Peg-IFN-α-2a group at a ratio of 2:1. The patients in both groups were given oral ribavirin for 48 weeks in addition and then followed up for 24 weeks after drug withdrawal. Abbott Real Time HCV Genotype II was used to determine HCV genotype, and Cobas TaqMan quantitative real-time PCR was used to measure HCV RNA level at 0, 4, 12, 24, 48, and 72 weeks. Adverse events were recorded in detail. The primary efficacy endpoint was sustained virological response (SVR), and a non-inferiority test was also performed. Results: A total of 561 patients with genotype 1/6 CHC were enrolled, among whom 529 received treatment; 90.9% of these patients had genotype 1 CHC. The data of the full analysis set showed that SVR rate was 69.80% (95% CI 65.00%-74.60%) in the trial group and 74.16% (95% CI 67.73%-80.59%) in the control group (P = 0.297 0). The data of the per protocol set (PPS) showed that SVR rate was 80.63% (95% CI 76.04%-85.23%) in the trial group and 81.33% (95% CI 75.10%-87.57%) in the control group (P = 0.849 8), and the 95% CI of rate difference conformed to the non-inferiority standard. The analysis of the PPS population showed that of all subjects, 47.9% achieved rapid virologic response, with a positive predictive value of 93.8%. The incidence rate of adverse events was 96.30% in the trial group and 94.94% in the control group, and the incidence rate of serious adverse events was 5.13% in the trail group and 5.06% in the control group. Conclusion In the regimen of Peg-IFN-α combined with ribavirin for the treatment of genotype 1/6 CHC, the new investigational drug Peg-IFN-α-2b(Y shape, 40 kD) has comparable clinical effect and safety to the control drug Peg-IFN-α-2a.