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This study aims to synthesize a magnetic resonance imaging (MRI) contrast agent that can specifically target the asialoglycoprotein receptor of liver cancer cells and evaluate its ability as a targeted MRI contrast agent. Lactobionic acid (LA) and polyethylene glycol (PEG) were used to modify superparamagnetic iron oxide nanoparticles (SPION) to obtain LA-PEG-SPION. LA-PEG-SPION was uniformly spherical under the electron microscope, with regular morphology and good dispersion. The particle size of LA-PEG-SPION was about 30 ± 4.5 nm, and its surface potential was about 31 ± 1.5 mV. LA-PEG-SPION had no toxicity or low toxicity to HepG2 cells and HeLa cells, even at 400 μg/mL. The uptake of LA-PEG-SPION by HepG2 cells was higher than that of SPION, with increased blue-stained particles. The fluorescent labeling rate of HepG2 cells reached 68.8%, which was higher than that of the control group. In vitro, MRI showed that the T2-weighted signal intensity of HepG2 cells was lower than that of the control group. Conclusively, LA-PEG-SPION nanoparticles are synthesized in a simple and efficient way. They are successfully applied to the T2-weighted contrast-enhanced MRI in liver cancer in vitro, and they have the potential to be used for in vivo research and clinical studies.

Since critical discourse analysis (CDA) was introduced to China in 1990s, it has developed into an influential and thriving field. This article reviews the development of CDA in China from 2011 to 2021, during which CDA had thrived to be a productive field in terms of the in-depth theoretical and methodological explorations and the overwhelming majority of empirical studies which considerably expanded its scope to a much wider range of discourses. It also came to involve a broader array of disciplines including corpus linguistics, cognitive linguistics, multimodality, translation studies, and eco-linguistics. It can be found that while keeping pace with the international CDA studies, Chinese scholars consistently gear CDA to China's social, political, and cultural contexts and strive to use CDA to deliberate on and solve social problems in contemporary Chinese society. This brief review endeavors to communicate with the international academia regarding the latest developments of CDA in China. [ABSTRACT FROM AUTHOR]

The periodic flooding characteristic of annular flow in a narrow rectangular duct is one of the phenomena of air and liquid flowing in reverse through rod bundle structure space of the reactor core, and the research on the characteristics of flooding behaviors, occurrence conditions, and flooding mechanism can provide data and theoretical support for the accident treatment of nuclear power plant. In this study, the periodic flooding characteristics of annular flow in a narrow rectangular duct were investigated, the high-speed photographic observation shows that each cycle of the flooding process consists of four flow regions, i.e., the onset flooding region, the full flooding region, the liquid membrane reversal region and the liquid phase downstream region. When the liquid phase flow rate is low, the annular flow flooding period increases slightly with the increase of the gas phase velocity, and when the liquid phase flow rate is high, the flooding period decreases with the increase of the gas phase velocity. The time proportion of the full flooding region gradually increases with the increase of the gas phase velocity, and the time proportion of the liquid phase downstream region gradually decreases until the annular flow reaches the complete rising pattern. In the area of low liquid phase velocity, the time of the onset flooding region increases with the increase of the gas phase velocity, while the time of the liquid membrane reversal region remains the same. In the area of high liquid phase velocity, the time of the onset flooding region and the liquid membrane reversal region decreases correspondingly. According to the experimental results, the mechanism of the periodic flooding behavior analysis was obtained. The thickness of the liquid film in annular flow increases because of the space bondage in the narrow rectangular duct, which makes the periodic flooding time increasing and the flow range of downward liquid phase increasing at the same time. The fundamental reason for the periodic flooding of annular flow in the narrow rectangular duct is the “protection” effect of the channel structure on the top layer of the liquid phase. The multiscale permutation entropy of the annular flow is disordered when the gas phase velocity is small, while the entropy of the annular flow gradually decreases with the increase of the gas phase velocity when the gas phase velocity is high, so the judgment conditions of the liquid phase declining and complete rising can be determined by the conversion point of “unordered” to “ordered” of the multiscale permutation entropy.

Background: Gene therapy has been widely concerned because of its unique therapeutic mechanism. However, due to the lack of safe and effective carries, it has not been widely used in clinical practice. Glypican 3 (GPC3) is a highly specific proteoglycan for hepatocellular carcinoma and is a potential diagnostic and therapeutic target for hepatocellular carcinoma. Herein, to monitor the effect of gene therapy and enhance the transfection efficiency of gene carriers, GPC3-modified lipid polyethyleneimine-modified superparamagnetic nanoparticle (GLPS), a type of visualized carrier for siRNA (small-interfering RNA) targeting the liver, was prepared., Methods: We performed in vitro gene silencing, cytotoxicity, and agarose gel electrophoresis to identify the optimal GLPS formulation. In vitro MRI and Prussian blue staining verified the liver-targeting function of GLPS. We also analyzed the biocompatibility of GLPS by co-culturing with rabbit red blood cells. Morphological changes were evaluated using HE staining., Results: The GLPS optimal formulation consisted of LPS and siRNA at a mass ratio of 25:1 and LPS and DSPE-PEG-GPC3 at a molar ratio of 2:3. GLPS exhibited evident liver-targeting function. In vitro , we did not observe morphological changes in red blood cells or hemolysis after co-culture. In vivo, routine blood analysis revealed no abnormalities after GLPS injection. Moreover, the tissue morphology of the kidney, spleen, and liver was normal without injury or inflammation., Conclusion: GLPS could potentially serve as an effective carrier for liver-targeted MRI monitoring and siRNA delivery., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Under the new pattern of high-quality development, the 2021 Briefing Report on Quality Control of Medical Devices in Shanghai Hospitals at All Levels will be subjected to secondary data processing, and the radar map analysis method will be used to visually evaluate the quality control effects and differences of medical devices in different types of hospitals in Shanghai. Analyze the quality level of medical device management in hospitals at all levels in Shanghai, study the key parts that affect the quality effect, and provide more theoretical basis for the effective control of medical device management quality. From the radar chart, the overall medical device level of tertiary hospitals is higher than that of secondary hospitals, and the overall coverage area is also larger. The overall quality balance of tertiary specialized hospitals needs to be improved urgently, mainly focusing on medical consumables and on-site inspection. There is a big gap in the quality control level of medical devices in other second-level hospitals, but the preparations for quality control training are more comprehensive. Hospital medical device management should pay more attention to specialized hospitals, low-level hospitals and socially run hospitals, and continuously improve the quality control system. At the same time, strengthen the standardization of medical device management and standardization of quality control, and promote the healthy and stable development of medical devices.

In order to improve the transfection efficiency of gene vectors and monitor the effect of gene therapy, this study prepared a drug delivery vector with dual functions. The thiourea reaction was used to synthesize polyethyleneimine (PEI, MW: 1.8 kDa) with superparamagnetic iron oxide nanoparticles (SPION) (PEI1800-SPION), and the lipid polycationic gene vector PEI1800-SPION loaded cationic liposome (LP-PEI1800-SPION) was further prepared by ethanol injection method. Agarose gel electrophoresis experiment, cytotoxicity experiment, and In-vitro gene silencing experiment were used to evaluate the vector and screen the optimal prescription of LP-PEI1800-SPION/siRNA. When the weight ratio of LP-PEI1800-SPION to siRNA is 20, the transfection efficiency of the nanoparticles was the highest, and the silencing efficiency of the target protein was the largest. The cytotoxicity of LP-PEI1800-SPION was low; when the concentration was in the range of 1-50 μg/mL, the survival rate of the four types of cells was above 80%. Prussian blue staining experiments and In-vitro MRI imaging experiments showed that cells had significant uptake and imaging capabilities for LP-PEI1800-SPION. In conclusion, the visualized polycationic lipid siRNA delivery vehicle (LP-PEI1800-SPION) was successfully prepared in this experiment, which provides a research basis for further theranostics of liver cancer.

The artificial intelligence based on medical aid diagnosis has been in full swing in these years. How to better and more safely utilize this new technology to improve the diagnostic efficiency and quality of doctors poses new challenges for our hospital management. This paper aims to explore relevant management problems and corresponding solutions from seven aspects:data security, system integration, technical parameters, risks, workflows and diagnosis results by introducing a new intelligent image screening system. After these management problems have been better solved, we found that the intelligent image screening system can improve the diagnostic efficiency and quality of doctors.

Objective: To investigate superiorities of a special needle-over-cannula adopting different location methods for continuous femoral nerve block (CFNB) for geriatric lower extremity joint arthroplasty., Methods: 60 elderly patients intending to receive scheduled knee or hip replacement surgery were recruited and divided into 3 groups randomly. Group 1 (n=20) adopted fascial pop for continuous femoral nerve block and postoperative analgesia with indwelling cannula. Group 2 (n=20) adopted location guided by B ultrasound, and Group 3 (n=20) adopted fascial pop combined with B ultrasound., Results: There was significant difference in the performing time of cannula indwelling on average between each two groups (P<0.01). There was no significant difference among three groups about visual analogue scale (VAS) score, Ramsay sedation score (RSS), incidence of nausea and vomit, or patient's satisfaction at 6, 12, 24 and 48 h. Infection at the puncture site, toxic reaction of local anesthetics and respiratory depression were absent during the cannula indwelling. All the patients did not receive any other analgesic, and the indwelling time of external cannula was 45.3 hours on average. There was only one patient in group 2 who felt mild pains in front of the thigh after removing the indwelling cannula. No stolidity or other abnormal symptom was found among the remaining patients., Conclusions: Shorter indwelling cannula time and higher success rate of single attempt placement suggest that fascial pop combined ultrasound guidance is worth for clinical recommendation.

Objective: To explore the protective effects and mechanism of ethanol extract of Inonotus obliquus (EEIO) injection on asthmatic mice., Method: OVA was injected intraperitoneally and inhaled to produce the asthmatic model. Thirty two mice were randomly divided into four groups: control group, asthma group and I. obliquus groups of high and low dose. The concentrations of IL-4, IL-5, IL-13 and IFN-gamma in BALF, the phosphor-p38 MAPK in lung tissues were respectively measured by ELISA and Western blotting. The number of inflammatory cells in BALF and histopathology changes were observed., Result: In asthmatic group, the number of inflammatory cells and the concentrations of IL-4, IL-5, IL-13 in BALF and phospho-p38 MAPK in lung tissue were higher, while IFN-gamma were lower than those in normal control mice (P < 0.05). In I. obliquus group, the number of inflammatory cells, the concentrations of IL-4, IL-5, IL-13 in BALF and phosphor-p38 MAPK in lung tissue were lower, but were higher than those in normal control mice (P < 0.05), and histropathology damage was alleviated significantly. There was no significant difference observed among the efficacies in the I. obliquus groups of high and low dose., Conclusion: p38 MAPK may play a role in pathological process of asthma. I. obliquus effectively treats asthma by inhibiting the expression of phosphor-p38 MAPK, correcting the unbalance of IFN-gamma/IL-4 and decreasing the number of inflammatory cells.