Ventilator associated pneumonia (VAP) is a challenging complication of critical illness.Aerosolized antibiotic is an option for the management of VAP currently,as it is reported that it could increase levels of drug in alveolar without increasing systemic toxicity.The articles that focused on the aerosolized antibiotics in the treatment of VAP and its influence factors were reviewed,and it was found that to achieve maximum drug delivery efficiency and reduce the influence of nebulization method,some factors,such as ventilation modes,tidal volume,nebulizer type,should be adjusted and monitored during the treatment.

Objective:To investigate the changes of gene or protein expression and activity of matrix metalloprotein9 (MMP9) and tissue inhibitor ofmetalloproteinasel (TIMP1) in the carotid artery (CA) of 4 wk hindlimb unweighted rat.Methods:A 4 weeks(wk) hindlimb unweighted (HU) rat model was used to simulate the effect of weightlessness on the cardiovascular system.Transmission electron microscopy was used to detect the content of ECM.Reverse transcriptase polymerase chain reaction(RT-PCR) was conducted to measure the mRNA content MMP and TIMP1.Immunohistochemistry and Western blot technique were used to measure the protein abundance.Gelatin zymography was carried out to detect the activity of MMP9.Results:Compared to the control group (CON),the area of ECM was enhanced (P＜0.05) and the content of collage fiber was increased (P＜0.05) in the CA of HU rats;moreover,HU did not affect the mRNA expression of MMP9,but significantly reduced the protein content (P＜0.05) or enzymatic activity (P＜0.05).Accordingly,the mRNA or protein expression of TIMP1 in the CA was significantly increased by HU (P＜0.05).Conclusion:Simulated weightlessness caused imbalance between MMP and TIMP1 expression,which might contribute to the ECM aggregation and stiffness of CA.

Posterior cortical atrophy (PCA) is a kind of neurodegenerative dementia. The core feature of the PCA includes progressive decline in visual processing and other posterior parietal-occipital cortex-related cognitive functions. Recently, neuroimaging features of PCA from magnetic resonance imaging/single photon emission computed tomography/ 18F-deoxyglucose positron emission tomography-computer tomography studies represent the typical characteristics of cortical atrophy, hypoperfusion, and hypometabolism in the posterior parietal-occipital cortex. The most common neuropathological changes of PCA are amyloid plaques deposition and neurofibrillary tangles in posterior cortex, while the molecular biomarkers are decreased amyloid β-protein 1-42 together with increased T-tau and/or P-tau in cerebral spinal fluid. From this point, PCA is also considered as an atypical form of Alzheimer′s disease (AD). However, individuals fulfilling the criteria for the core clinico-radiological PCA syndrome, can also fulfill the core clinical criteria for any other neurodegenerative syndrome, and represent negative AD-related pathophysiological biomarkers. Heterogeneity within the PCA syndrome and pathophysiological biomarkers prompt the PCA working group to establish a new consensus on PCA classification and diagnostic criteria, which is proposed for use in a number of different research contexts and the research of AD, atypical AD and related syndromes. This paper gives a brief introduction and interpretation of the newly proposed classification and diagnostic criteria of PCA.

In recent years,magnetic resonance imaging (MRI) has been widely used in the early diagnosis as well as long-term follow-up study of Alzheimer's disease (AD).The studies were reviewed which applied the structural MRI and arterial spin labeling MRI (ASL-MRI) in AD over the past 20 years,and found more gray matter volume loss in multiple brain structures in individuals with AD spectrum.Among them,medial temporal lobe atrophy and posterior cortical atrophy are the most diagnostic.Meanwhile,cerebral blood flow changes in various brain regions with the progression of the AD.More investigations combining the changes of gray matter volume and cerebral blood flow to explore pathophysiological mechanisms underlying cognitive decline in AD spectrum are necessary in the future.

Military flying labor hygiene is a discipline that focuses on influences of special flight environment and labor condition on human body and related prevent measures, with the core of flight fatigue. Health information and technique training can help flight surgeons to enhance professional competency and improve the prevention and recovery of military flying fatigue. The course construction of teaching system in this study included survey of demand, arrangement of content, identification of strategy, determination of evaluation, and feedback of results. Meanwhile, the textbook compilation, cultivation of teaching team and construction of laboratory were also needed. After a 4-year practice, a formal teaching system has been established and its teaching effectiveness has basically fulfilled the professional requirement for flight surgeons.

Objective:To investigate the molecular characteristics of obacunone, and to screen and identify potential targets of obacunone against sepsis.Methods:The pharmacological parameters and molecular characteristics of obacunone were analyzed with the aid of the Traditional Chinese Medicine Systems Pharmacology Database Analysis Platform (TCMSP). The potential targets of obacunone against sepsis were screened using SwissTargetPrediction and Drug Repositioning and Adverse Drug Reaction Chemical-Protein Interactome (DRAR-CPI) software, with a Z'-score < -0.5. The anti-sepsis targets of obacunone were selected by Online Mendelian Inheritance in Man (OMIM), Comparative Toxicogenomics Database (CTD) and Therapeutic Target Database (TTD). The anti-sepsis potential target was identified by molecular docking software.Results:The oral bioavailability of obacunone was 81.58% and the drug-likeness was 0.57 indicating that obacunone showed good drug formation. A total of 242 potential targets were screened through SwissTargetPrediction and DRAR-CPI software, 13 targets were directly related to sepsis. Cathepsin G (CTSG), caspase-1 (CASP1), S100 calcium binding protein A9 (S100A9), protein C (inactivator of coagulation factors Ⅴa and Ⅷa, PROC), mitogen-activated protein kinase 1 (MAPK1), glucose-6-phosphate dehydrogenase (G6PD), interleukin-10 (IL-10), migration inhibitory factor (MIF), complement C5a receptor 1 (C5AR1), caspase-3 (CASP3), CXC chemokine receptor 2 (CXCR2), thrombin receptor (F2R), nicotinamide phosphoribosyltransferase (NAMPT) were identified as the potential targets for anti-sepsis of obacunone by molecular docking software, the free binding energies were -32.55, 1.26, -30.00, 300.08, -31.88, -30.29, -21.38, -30.79, 16 777.84, -21.80, 6 443.36, -20.38, -23.47 kJ/mol, respectively.Conclusions:Obacunone can inhibit blood coagulation and improve inflammatory response by regulating PROC and F2R. It regulates MIF, S100A9, G6PD and IL-10 to play a role in immune response. It regulates CTSG, CASP1, MAPK1, C5AR1 and CASP3 to protect sepsis-damaged organs. By regulating CXCR2, it can reduce the excessive migration of neutrophils to the site of inflammation, alleviate tissue damage. By regulating NAMPT, it improves cellular energy status, reduces oxidative stress, and protects cells from damage.

An expression vector pET-28a-mGM-CSF-X10-βhCGCTP37 plasmid containing the βhCG and mGM-CSF gene was designed and constructed. The fusion protein was induced by lactose and purified by ammonium sulfate precipitation and DEAE-cellulose anion exchange column. Then dendritic cells(DC)in C57BL/6J mice were extracted and sensitized by the fusion protein to obtain DC vaccine. The DC vaccine was inoculated to C57BL of / 6J mice with prostate cancer RM-1. The results indicated that the anti-tumor effects of DC group and DC combined with paclitaxel(DP)group were superior to that of paclitaxel(Pac)group(P< 0. 01), and the anti-tumor effect of DP group was better than that of DC group. Thus, the constructed DC vaccine can inhibit the growth of prostate cancer, and have synergistic anti-tumor when used with paclitaxel.

Objective:To investigate the accuracy of free-breathing CT in evaluating the volume and shape of epicardial adipose tissue (EAT), and further explore the characteristics of EAT volume and activity in patients with atrial fibrillation using 18F-FDG PET/CT " one-stop" imaging. Methods:(1) Retrospective analysis was performed on 20 patients (16 males, 4 females, age: 33-86 (61.1±14.2) years) who underwent 18F-FDG PET/CT imaging and without obvious diseases affecting the images of the heart and surrounding lungs between March 2020 and May 2020 in Beijing Chaoyang Hospital. Free-breathing CT and breath-hold high resolution CT (HRCT) images were reviewed. Spearman rank correlation analysis, Bland-Altman consistency analysis and intraclass correlation coefficient (ICC) were used to evaluate the correlation and consistency of the EAT volume and shape, as well as the repeatability of the two operators′ measurements. (2) Prospective analysis was conducted to compare the differences in EAT volume and 18F-FDG uptake values between 20 patients (6 males, 14 females, age: 52-76 (66.0±6.4) years) with atrial fibrillation and 10 healthy controls (3 males, 7 females, age: 59-69 (66.0±3.6) years) collected between August 2017 and August 2018 in Beijing Chaoyang Hospital. Mann-Whitney U test was used to compare the differences in EAT volume and 18F-FDG SUV max between patients with atrial fibrillation and healthy controls. EAT volume measurement was conducted by the combination of Mimics Research 21.0 software and manual analysis. The shape of EAT was automatically calculated by the same software to obtain the maximum length of the projection of the three-dimensional (3D) model on the reference axes ( x, y, z). SUV max of EAT was manually measured. Results:The measurements of EAT volume had good repeatability (intra-operator ICC=0.999; inter-operator ICC=0.997). There was a good correlation and a good consistency between EAT volumes measured by free-breathing CT and breath-hold HRCT (96.6 (79.9, 136.4) vs 96.2 (80.9, 135.8) ml; rs=0.929, P<0.001); data of 19 cases were within 95% limits of agreement (95% LoA). The maximum projection length of EAT 3D model on the reference coordinate axis also showed good correlation and consistency ( x axis: rs=0.869, P<0.001, data of 19 cases were within 95% LoA; y axis: rs=0.854, P<0.001, data of 18 cases were within 95% LoA; z axis: rs=0.586, P=0.007, data of 20 cases were within 95% LoA). EAT volume of atrial fibrillation group was higher than those of healthy control group (137.2 (113.9, 202.9) vs 94.4 (76.6, 134.4) ml; z=-2.11, P=0.035) and SUV max of EAT in the atrial fibrillation group was higher than that in healthy control group (1.2 (1.1, 1.5) vs 1.1 (1.0, 1.2); z=-2.14, P=0.035). Conclusions:Free-breathing CT and breath-hold HRCT have good correlation, consistency and repeatability in measurement of EAT volume and shape. 18F-FDG PET/CT can be a " one-stop" imaging strategy for the evaluation of EAT volume and activity.

Objective:To evaluate the standardized residency training of obstetrics and gynaecology in Shengjing Hospital of China Medical University with Milestones evaluation system of obstetrics and gynecology, and to evaluate the feedback effect of the system.Methods:An improved Milestones evaluation form was developed to evaluate the self-evaluation and clinical tutor's scores, collect the results and make a statistical analysis of the 1-3 years standardized training residents of the Shengjing Hospital of China Medical University in September 2019. GraphPad Prism 8 software was used for data collection and statistical analysis, and Box-Plots software was used for drawing analysist. Descriptive statistics method was used for the general situation of the research objects. After the students' self-evaluation and tutor's scores passed the normal distribution and variance homogeneity test, paired t test was performed, and the scores of residents from different sources were analyzed by variance analysis. Results:A total of 164 residents of obstetrics and gynaecology were evaluated, and there were significant differences between self-evaluation and teacher's evaluation in medical knowledge, learning ability and system work ( P<0.05). The competency scores of the first year residents ranged from 3.003 to 4.556, and at the end of the course they increased to 4.921 to 5.974, showing statistically significant differences in each item compared with the first year ( P<0.001). After three years of training, residents from different sources showed significant improvement ( P<0.001). Conclusion:The Milestones evaluation system of the obstetrics and gynecology can be used for the training assessment and feedback of the residents in obstetrics and gynecology specialty. The self-assessment of residents helps to understand the level of self-assessment, and the teacher's evaluation helps to correct the bias generated by self-assessment. The systematic and staged Milestones evaluation system can instruct the clinical tutors to instruct the residents in accordance with their aptitude, and give feedback on the training effect of the residency training base.

Objective To analyze the incidence of and risk factors for white matter hyperintensity(WMH)in pilots.Methods A retrospective case-control study was performed.The subjects were 1,415 pilots ages 19 to 58 who had undergone cranial MRI examination in a hospital between September 2020 and August 2023.They were divided into two groups:the WMH group and the control group(without WMH).Univariate and multivariate logistic regression analysis were used to identify the risk factors for WMH.Results There were 219 cases in the WMH group and 1,196 cases in the control group.The total incidence of WMH was approximately 15.48％,with mild,moderate and severe cases of WMH accounting for 70.78％,24.20％,and 0.47％,respectively.Regression analysis results showed that age(OR=1.625,95％CI:1.099-2.404)and flight time(OR=1.282,95％CI:1.033-1.592)were risk factors for WMH in pilots.Conclusion The incidence of WMH in pilots was approximately 15.48％.Most of WMH were mild according to Fazekas grading.Age increase and long flight time are risk factors for WMH in pilots.