Objective To evaluate the clinical value of spectral CT mode in imaging liver by comparing the radiation dose and image quality between spectral CT and conventional multi-slice spiral CT (MSCT).Methods Thirty patients (group A) underwent three-phasic enhanced CT scans spectral CT mode in the portal phase (PP) and conventional helical mode in other phases (Discovery CT 750 HD,GE Healthcare).Another 30 patients in group B underwent conventional three-phasic enhanced CT on a 64-slice MSCT (VCT,GE Healthcare) with 120 kVp and automatic tube current modulation (ATCM) and noise index of 15.The images in PP from the two imaging modes were retrospectively compared.The contrast-noiseratio (CNR) for the veins was calculated using liver parenchyma as background.For the spectral CT mode,101 sets of monochromatic images were reconstructed from 40 to 140 keV,and the optimal energy level for obtaining the highest CNR was determined using the Gemstone Spectral Imaging (GSI)-viewer software.Image noise (at 70 keV),CNR (at the optimal keV level) for the vein and radiation dose to the patient were obtained for spectral images and statistically compared with those in group B with the conventional MSCT using t test.Results The CTDIw value in PP for spectral CT was 15.64 mGy,30％lower than the (22.44 ± 5.09) mGy for the conventional MSCT (t =29.56,P ＜ 0.01).Image noises on the liver parenchyma were 22.81 ±2.85 and 23.80 ±3.31 for the conventional MDCT and spectral CT images at 70 keV,respectively,with no significant difference (t =0.76,P ＞ 0.05).On the other hand,CNR for the vein at the optimal energy level in spectral CT was 7.17 ± 2.09,which was significantly higher than the 2.76 ± 1.34 for the conventional MSCT (t =7.21,P ＜ 0.01).Conclusion Compared with conventional standard-dose liver MSCT,spectral CT imaging provides improved CNR for vessels,comparable image noise for liver parenchyma with 30％ dose reduction.

Objective: To investigate the role of miR-19a/b in myocardial ischemia reperfusion injury (R/I) with its clinical significance. Methods: Our research included in 2 parts. Part 1: in H9c2 cells. miR-19a/b expression in H9c2 cells with 10 h hypoxia and 2 h re-oxygenation was detected by real-time PCR, miR-19a/b potential target gene was assessed by luciferase reporter activity assay. Part 2: in natural person. Control group,n=40 healthy subjects and AMI (acute myocardial infarction) group,n=40 relevant patients. Peripheral blood levels of miR-19a/b were detected as Part 1, cTnI were measured by chemiluminescence immune analysis and CK-MB were assessed by immune inhibition method. Results: Part 1: Compared with normal H9c2 cells, miR-19a/b expressions were increased 5.876 times and 2.761 times in H9c2 cells with 10 h hypoxia and 2 h re-oxygenation, bothP<0.01. With respectively transfected miR-19a/b mimic and inhibitor, miR-19a/b expression was up-regulated and down-regulated respectively. miR-19a/b and chromosome-10 deleted phosphatase, tensing homolog gene (PTEN) had the targeting effect. With up-regulated miR-19a/b expression, PTEN level was decreased and with down-regulated miR-19a/b expression, PTEN level was increased. Part 2: Compared with Control group, AMI group had elevated blood level of miR-19a/b,P<0.01. In AMI patients, miR-19a/b was increasing at 0-3 h of chest pain and reaching the peak at 6-12 h; CK-MB enzyme activity and cTnI content were elevating at 2-6 h of onset and reaching the peak at 24 h. Conclusion: miR-19a/b expression was up-regulated by myocardial ischemia reperfusion in H9c2 cells, PTEN was the potential target gene of miR-19a/b. Circulating miR-19a/b might be used as a new non-invasive biological marker for myocardial ischemia R/I diagnosis.

As a member of G protein coupled-receptors superfamily, free fatty acid receptor 1 (FFAR1), is also known as GPR40, has been shown to regulate numerous pathophysiological processes in a variety of tissues and organs. The activated FFAR1 has a variety of biological functions. For instance, it can not only regulate metabolism of fatty acids and glucose, but also play an important role in immune inflammatory response, it may be a potential drug target for the treatment of various chronic inflammatory diseases. In this review, we focus on the recent researches of FFAR1's action in the regulation of pathophysiological processes, its molecular mechanism and new agonists development. At the same time, this review will take the discovery of series FFAR1 agonists as examples, and display the applied prospects of FFAR1.

Objective To explore the construction of clinical medical engineering emergency support mode in medical rescue. Methods The deficiencies of emergency support mechanism were discussed from the aspects of support requirements, planning, personnel training, equipment and materials reserve. From the aspects of basic function mode, emergency support commanding mode, personnel allocation the framework design of the support mode was carried out with the principles of quickness, high quality, obedience and initiative. Results The mode completed medical emergency support mechanism and enhanced the efficiency of emergency medical treatment during disasters and etc. Conclusion Emergency support is of great significance for medical rescue, which has to pose emphases on military-civilian integration, research and planning.

Objective To investigate the usefulness of three-dimensional reconstruction in the preoperative evaluation of the texture of pituitary tumors. Methods Seventy patients with pituitary tumors admitted to our hospital between January 2015 and July 2018 were enrolled in the study. All patients underwent enhanced MRI scanning before surgery. They were classified into the soft group, medium group, and tough group according to the tumor texture. The patient's clinical data, MRI images, and surgery conditions were collected.The Mimics software was used to reconstruct the three-dimensional models of pituitary adenomas. The volume and surface area of different tumor signal groups were calculated and analyzed. In addition, the relationships between tumor size, tumor resection, and postoperative complications were analyzed. Results The three-dimensionally reconstructed model of the pituitary adenoma had a clear outline and was consistent with the tumor area in the MRI images. The calculated average threshold accurately segmented the images. Grouped by the classification of texture, the differences of the proportions of each part were statistically significant (P ＜ 0.01). According to the ordinal polytomous logistics regression analysis, the proportion of the volume of the higher part positively correlated with the tumor texture (P ＜0.05), and the ratio of the surface area of the medium part to the overall surface area positively correlated with the tumor texture (P ＜ 0.05).Conclusion The use of Mimics software for 3 D reconstruction of preoperative MRI images can accurately predict the tumor texture in pituitary tumors and can provide a basis for the choice of surgical methods.

Aim To investigate the effect of miR-199a-5p on the proliferation and migration of human glioma cells. Methods U251 cells were selected as experimental subjects to construct a U251 cell line overexpressing miR-199a-5p. The experiment was divided into; control group (U251 cells without transfection, Control), negative control group (transfected with empty vector plasmid U251 cells, NC) and experimental group (transfected with miR-199a-5p mature mimics, mimics). Real-time fluorescent quantitative PCR was used to detect the expression of miR-199a-5p in each group; CCK-8 was used to detect the proliferation of cells transfected with miR-199a-5p; the cell scratch test and Transwell migration test were used to detect the migration of U251 in each group; Western blot was applied to detect DDR1 expression; a U251 cell line overexpressing DDR1 was constructed to detect the effect of overexpression of DDR1 on the proliferation and migration of U251 cells transfected with miR-199a-5p. Results The level of miR-199a-5p in mimics group was significantly higher than that in control group (P < 0.01), the cell viability was reduced (P < 0.01), and the proliferation ability was weakened (P <0. 01). The expression of DDR1 in miR-199a-5p group cells was significantly reduced (P < 0. 01). Compared with mimincs group, the pcDNA3. 1-DDR1 transfected group could up-regulate DDR1 (P < 0. 01), increase cell viability, and promote cell proliferation (P < 0. 05 or P < 0. 01). Conclusions miR-199a-5p can down-regulate the expression of DDR1 and inhibit the proliferation and migration of human glioma cells.

Radiotherapy is a treatment for cancer with undesired by-effects. In order to develop a new radiation protective agent that could reduce the by-effects, we tried to express and purify human cryptochrome 1 (hCRY1). The coding sequence of hCRY1 was inserted into prokaryotic expression plasmid pET28a(+), and this protein was purified from Escherichia coli BL21(DE3) after IPTG induction, ultrasonication, inclusion body dissolution, gradient dialysis, nickel column purification and ultrafiltration. The yield of hCRY1 in 1 L E. coli culture (LB medium) was about 10-15 mg. The radiation protective efficiency of hCRY1 was monitored by detecting X-ray-induced H2A.X foci in HaCaT cells. The results of immunofluorescence show that hCRY1 significantly reduces X-ray stimulated DNA damage response. The apoptosis of HaCaT cell was also detected, and the repression of H2A.X foci formation was not due to hCRY1's cytotoxity. All these data suggest a potential application of recombinant hCRY1 as a protective agent for radiotherapy.
Cryptochromes ; biosynthesis ; Escherichia coli ; Humans ; Plasmids ; Radiation-Protective Agents ; Recombinant Proteins ; biosynthesis

In recent years, bio-metal organic frameworks (Bio-MOFs) synthesized with biocompatible ligands have been widely investigated as a potential drug delivery carrier due to their large specific surface area and porosity, rich host-guest intermolecular interactions, and good biocompatibility.In this review, we summarized the design methods of Bio-MOFs including structural and toxic factors, as well as a variety of drug loading methods including click chemistry, with particular focus on recent research advances in Bio-MOFs for pulmonary drug delivery systems, improving pharmaceutical properties of drugs, sustained and controlled drug release, stimulation response and targeted drug delivery systems.Finally, we summarized the bottlenecks that constrain the development of Bio-MOFs in clinical studies of actual pharmaceutical formulations and their future directions for approved formulations, aiming to provide some theoretical reference for promoting the application of Bio-MOFs in drug delivery systems.

Objective:To explore the scheme of accurate pelvic osteotomy parameters and to analyze the feasibility and efficacy of 3D printing navigation plate in developmental dysplasia of the hip surgery.Methods:From January 2015 to December 2017, a total of 18 children with DDH underwent computer-assisted Salter pelvic osteotomy (computer-assisted osteotomy group) and 25 children with DDH who underwent conventional Salter pelvic osteotomy (conventional osteotomy group) were selected for retrospective analysis. There were 11 males and 32 females with an average age of 3.2±2.5 (range 1-11) years. According to International Hip Dysplasia Institute (IHDI) classification, there were 20 cases of type 1, 9 of type 2, 12 of type 3 and 2 of type 4. All patients were unilateral dislocation, including 18 cases on the left and 25 on the right. All children underwent pelvic CT examination before operation. Further, the proximal femur was surgically corrected during the operation. According to the acetabular rotation angle (ATA) and bony acetabular index (BAI), the computer-assisted osteotomy group simulated the operation with Mimics software made 3D printing navigation plate through which an accurate osteotomy scheme was developed. The two groups were compared in operative duration, intraoperative blood loss, Japanese Orthopaedic Association (JOA) hip joint score. Acetabular index (AI), central edge (CE) angle, and acetabulum head index (AHI) were compared between the two groups by using postoperative X-ray. The acetabular tilt angle (ATA) changes before and after operation in the computer-assisted osteotomy group were compared through 3D CT.Results:The follow-up duration was 2.3±0.2 (2.0 to 2.5) years in the computer-assisted osteotomy group and 2.8±0.15 (2.5 to 3.0) years in the conventional osteotomy group. The operative duration in the computer-assisted osteotomy group was 127±20.6 min, which was significantly longer ( t=4.657, P<0.001) than that in the conventional osteotomy group (103±13.2 min). Intraoperative bleeding was 157±17.5 ml in the computer-assisted osteotomy group and 151±15.3 ml in the conventional osteotomy group without significant difference between the two groups ( t=1.195, P=0.239). At 2 years after surgery, the JOA score of the hip joint in the computer-assisted osteotomy group (86.7±8.5 points) was like that (84.8±10.0 points) in the conventional osteotomy group ( t=0.628, P=0.533). At the last follow-up, the CE angle in the computer-assisted osteotomy group (36.8°±5.2°) was significantly larger than that (31.8°±4.4°) in the conventional osteotomy group ( t=3.414, P<0.001). There was statistically significant difference in term of AHI between the computer-assisted osteotomy group (85.8%±6.6%) and the conventional osteotomy group (80.4%±8.3%, t=2.284, P=0.028). AI was 23.5°±5.5° in the computer-assisted osteotomy group and 25.2°±4.2° in the conventional osteotomy group without significant difference ( t=-1.150, P=0.257). The ATA of the affected side was 12.3°±1.4° in the computer-assisted osteotomy group which was similar ( t=0.614, P=0.547) to that of the healthy side (11.8°±2.8°). Conclusion:Based on specific anatomical parameters, computer-assisted preoperative planning can not only directly simulate the process of osteotomy, but also produce individualized 3D printed guide plates. Compared with conventional Salter pelvic osteotomy, computer-assisted osteotomy can achieve accurate radiographic correction of the hip joint in children with DDH, resulting in a better matching relationship between the femoral head and acetabulum.

Objective To introduce the method of dual immunofluorescence labeling of human dentin matrix without demineralization of the whole dentin fragments, and to analyze the distribution of type-Ⅰ collagen fibrils and chondroitin sulfate in human dentin.Methods Forty 30 μm-thick middle coronal dentin sections were obtained from 8 freshly extracted human third molars and etched with 37％ phosphoric acid(PA) gel for 15 s.After preconditioning with or without tosyl-phenylalanyl chloromethyl ketone(TPCK) treated trypsin digestion, sections were subjected to dual immunofluorescent labeling and scanned by confocal laser scanning microscopy to identify the type-Ⅰ collagen fibrils and chondroitin sulfate.Results Chondroitin sulfate was localized in the lumens of the dentin tubules and peritubular dentin, while the type-Ⅰ collagen fibrils were localized in intertubular dentin and peritubular dentin.After preconditioning with TPCK treated trypsin digestion, the red fluorescence was decreased or disappeared.Conclusions The dual immunofluorescence labeling methodology can be used to study the human dentin matrix without demineralization of the whole dentin fragments.Chondroitin sulfate was localized in the lumens of the dentin tubules and peritubular dentin, while the type-Ⅰ collagen fibrils were localized in intertubular dentin and peritubular dentin.