The therapeutic potential of indole hybrids, dimers, and trimers against drug-resistant ESKAPE pathogens.

Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter (ESKAPE) species as causative agents are characterized by increased levels of resistance toward multiple classes of first-line as well as last-resort antibiotics and represent serious global health concerns, creating a critical need for the development of novel antibacterials with therapeutic potential against drug-resistant ESKAPE species. Indole derivatives with structural and mechanistic diversity demonstrated broad-spectrum antibacterial activity against various clinically important pathogens including drug-resistant ESKAPE. Moreover, several indole-based agents that are exemplified by creatmycin have already been used in clinics or under clinical trials for the treatment of bacterial infections, demonstrating that indole derivatives hold great promise for the development of novel antibacterials. This review is an endeavor to highlight the current scenario of indole hybrids, dimers, and trimers with therapeutic potential against drug-resistant ESKAPE pathogens, covering articles published from 2020 to the present, to open new avenues for the exploration of novel antidrug-resistant ESKAPE candidates.

The efficacy and safety of vedolizumab in the treatment of 81 cases of active ulcerative colitis: a single center retrospective study / 中华消化杂志

Objective:To evaluate the efficacy and safety of vedolizumab (VDZ) in the treatment of active ulcerative colitis (UC).Methods:From November 1, 2020 to October 30, 2022, at the Department of Gastroenterology, the Sixth Affiliated Hospital of Sun Yat-sen University, 81 UC patients who received VDZ treatment and completed a 14-week follow-up were retrospectively selected. The clinical data of patients, including age, disease duration, disease activity of UC were collected. The VDZ efficacy evaluation included primary and secondary efficacy indicators. The primary efficacy indicator was the clinical remission rate after 14 weeks of VDZ treatment, and the secondary efficacy indicators included the clinical response rate, steroids-free remission rate, endoscopic remission rate after 14 weeks of treatment as well as the clinical response rate, clinical remission rate, steroids-free remission rate, secondary loss of response rate after 52 weeks of treatment. The adverse reactions during the treatment were recored. Taking clinical remission after 14 weeks of treatment as the dependent variable, univariate analysis was performed to identify the risk factors affecting clinical remission of VDZ. Binary logistic regression analysis was used for multivariate analysis to determine the independent risk factors of VDZ-included clinical remission. Chi-square test and Wilcoxon signed-rank test were used for statistical analysis.Results:Among the 81 UC patients, the age was 40.0 years old (29.0 years old, 53.5 years old) and the disease duration was 42.5 months (22.5 months, 94.7 months). The proportion of patients with mild active UC was 21.0% (17/81), the proportion of patients with moderate active UC was 64.2% (52/81), and the proportion of patients with severe active UC was 14.8% (12/81). After 14 weeks of treatment, the total Mayo score decreased from baseline level of 7.0 (6.0, 9.0) to 1.0 (0.0, 3.0), and the difference was statistically significant ( Z=-6.87, P<0.001). The clinical response rate was 84.0% (68/81) and the clinical remission rate was 69.1% (56/81) after 14 weeks of treatment. Of the 17 patients treated with combination of corticosteroid therapy, 10 achieved steroid-free remission, and the endoscopic remission rate was 34.8% (23/66). Of the 43 patients followed up to 52 weeks, the total Mayo score of UC patients decreased from baseline level of 7.0 (6.0, 9.0) to 0.0 (0.0, 1.0) after 52 weeks of treatment, and the difference was statistically significant ( Z=-3.25, P<0.001). The clinical response rate was 69.8% (30/43), and the clinical remission rate was 65.1% (28/43). Of the 13 patients treated with combination of corticosteroid therapy, 10 patients achieved steroid-free remission. The secondary loss of response rate was 15.2%(5/33) .The result of the univariate analysis showed that previous use of glucocorticoids was a risk factor of clinical remission after 14 weeks of VDZ treatment ( χ2=5.88, P=0.015). The result of multivariate logistic regression analysis showed that previous use of glucocorticoids was an independent risk factor of clinical remission after 14 weeks of VDZ treatment ( OR=3.429, 95% confidence interval 1.235 to 9.517, P=0.014). During the follow-up period, 12.3% (10/81) of patients developed Clostridium difficile infections, except for 1 case stopped VDZ treatment because the clinical response was not reached, remaining 9 cases continued VDZ treatment after received anti- Clostridium difficile treatment. Conclusion:VDZ has good clinical efficacy and safety in the treatment of Chinese UC patients, and patients with no history of glucocorticoid use may be more likely to achieve clinical remission after 14 weeks of treatment.

The investigation and analysis of eye lens dose to interventional radiology workers in China from 2019 to 2021 / 中华放射医学与防护杂志

Objective:To investigate and analyze the eye lens dose to interventional radiology workers in China from 2019 to 2021.Methods:The monitoring data on eye lens dose to interventional radiology workers from 31 province-level units during 2019-2021 were collected through the National Radiological Health Information Platform. The eye lens dose evaluation indicator was Hp(3), with each monitoring period of no more than 3 months. Kusall-Wallis H test was used for the comparison of multiple groups and pairwise. Results:A total of 6 643 interventional radiology workers were investigated from 2019 to 2021. The average annual eye lens dose was 1.03 mSv, with the median of 0.17 mSv and the maximum of 94.88 mSv. The annual eye lens dose to 59 workers exceeded 20 mSv. It was also found that the annual eye lens dose to the doctors in 2019 and 2020 was slightly higher than that to nurses (rank mean difference=118.29, 129.71, P<0.01), and the lens dose to interventional radiology workers who performed cardiac interventions in 2019 was higher than that to workers who performed peripheral vascular interventions (rank mean difference=46.52, P<0.05). Conclusions:The lens dose to interventional radiology workers is lower than the limits given in Chinese national standard currently in effect, but exceed the latest internationally recommended limit for a few ones. In order to protect the occupational health of interventional radiology workers, the monitoring of lens dose should be strengthened.

The necessity and countermeasures of strengthening radiation dose management in diagnostic radiology / 中华放射医学与防护杂志

In recent years, the diagnostic radiology, especially CT scanning, has a rapidly increased frequency in our country, becoming the largest artificial radiation source to the average individual doses to the population. In clinical diagnosis and treatment activities, the examined patients and individuals may undergo multiple procedures and multiple frequencies of medical imaging in a short period of time and receive high cumulative radiation doses even exceeding 50 or 100 mSv in a single day, posing a potential risk to their health. Therefore, it is necessary to carry out statistical analysis and management of diagnostic radiation dose information to minimize the probability of excessive dose and associated radiation risk. In this paper, the international cognition of radiation risks in diagnostic radiology, diagnostic equipment and medical imaging frequency, radiation dose and its management status are described. Four countermeasures for radiation dose management are put forward to provide reference for further improving radiation protection in clinical practice.

Analysis of individual dose monitoring results for radiation workers in Shandong province from 2016 to 2020 / 中华放射医学与防护杂志

Objective:To summarize the levels of individual dose to radiation workers in Shandong province from 2016 to 2020, and to analyze the trends in their change in order to provide scientific basis for radiation workers′ health management.Methods:The experimental detection and quality control were carried out in compliance with the national standards Specifications for individual monitoring of occupational external exposure (GBZ 128-2019) and the Testing criteria of personnel dosimetry performance for external exposure (GBZ 207-2016). The result of the personal dose monitoring of occupational external exposure of all radiation workers monitored by the Centers for Disease Control and Prevention in 16 cities of Shandong province were retrospectively analyzed by using SPSS 23.0 software.Results:The total number of monitored workers were 25 523 with an average annual individual effective dose of 0.28 mSv. There were statistically significant differences among radiation workers in different years ( H= 2 815.91, P<0. 001). The average annual individual effective dose showed an upward trend followed by a downward trend. The average annual effective dose of 0.55 mSv for nuclear medicine radiation workers in medical applications was the highest, with statistically significant differences among different occupational radiation workers ( H=310.37, P<0.001). The average annual effective dose of 0.37 mSv for radioactivity logging workers in industrial applications was the highest, with statistically significant differences among different occupational radiation workers ( H=448.07, P<0. 001). The average annual effective dose to radiation workers in medical applications was higher than in industrial applications ( Z = -14.93, P<0.001). Conclusions:The average annual effective dose to nuclear medicine radiation workers in medical applications and logging radiation workers in industrial applications are relatively high. There would be a push to furthe improve workplace protection measures and strengthen the management and supervision of radiological workers.

Application of measurement of pedicle parameters before L1 percutaneous vertebroplasty / 中国基层医药

Objective:The included angle of the outermost edge of the pedicle and the front edge of the central line of T12, L1, and L12 in the axial projection was compared before surgery (the incidence angle of the pedicle was set as α). A horizontal line passing through point C was made to cross the inner edge of the pedicle in the axial projection and the intersection point was designated as point D. The distance between point C and point D was compared among T12, L1, and L2. The advantages and feasibility of the measurement of these parameters for guiding puncture and bone cement injection in L1 percutaneous vertebroplasty were investigated.Methods:The clinical data of 91 patients with L1 osteoporotic vertebral compression fracture who underwent percutaneous vertebroplasty in The First People's Hospital of Chu Zhou from January 2018 to November 2021 were retrospectively analyzed. Axial α and CD of the L1 vertebral body and its adjacent vertebral bodies were measured. The amount of bone cement injected during the surgery, bone cement leakage rate, and pre- and post-surgery Visual Analogue Scale score were determined.Results:The α and CD of L1 in the axial projection were (20.43 ± 1.61)° and (5.37 ± 1.08) mm, respectively. Bone cement leakage rates of unilateral and bilateral approaches of L1 vertebral body were 35% and 12%, respectively, and there was a significant difference between the two approaches ( χ2 = 6.08, P < 0.05). There was no significant difference in the amount of bone cement injected during the surgery between unilateral and bilateral approaches of L1 ( P > 0.05). There was no significant difference in pre- and post-surgery Visual Analogue Scale scores between unilateral and bilateral approaches of L1 ( P > 0.05). Conclusion:The α and CD of L1 in the axial projection are smaller than those of other adjacent vertebral bodies, which is of great significance for selecting a puncture path and reducing bone cement leakage.

Factors influencing the levels of occupational exposure in medical radiation workers in China, 2021 / 中国辐射卫生

Objective To analyze the factors influencing the levels of occupational exposure in medical radiation workers in China, and to provide a scientific basis for determining the key points of radiation protection in the medical sector. Methods The individual monitoring data on occupational external exposure in medical radiation workers in 2021 were collected from the “National Individual Dose Registry”. The Chi-squared test and logistic regression were used to analyze the factors influencing the levels of occupational exposure in medical radiation workers. Results The Chi-squared test showed that gender, occupational category, medical institution category, region, number of radiation workers per thousand population, and regional per capita GDP were significantly associated with occupational exposure in medical radiation workers exceeding the annual effective dose of 5 mSv and an annual effective dose limit of 20 mSv (χ2 = 21.456−262.329, 7.601−78.650, P < 0.05). The logistic regression analysis further showed that gender, occupational category, region, and number of radiation workers per thousand population were factors influencing the occupational exposure in medical radiation workers exceeding the annual effective dose of 5 mSv (χ2 = 14.621−170.857, P < 0.05); gender, occupational category, region, and regional per capita GDP were factors influencing the occupational exposure in medical radiation workers exceeding the annual effective dose of 20 mSv (χ2 = 5.401−48.709, P < 0.05). Conclusion Male radiation workers in interventional radiology and in central China have high risks of exceeding annual effective doses of 5 and 20 mSv. Moreover, high number of radiation workers per thousand population and regional per capita GDP are associated with low risks. Medical institutions should maintain a sufficient number of radiation workers and strengthen training on radiation protection knowledge for male and interventional radiology workers to enhance their radiation protection awareness. Investigation of the factors contributing to the high occupational exposure in central China should be intensified, and targeted effective measures should be conducted to reduce the occupational exposure in medical radiation workers.

Monte Carlo simulation and analysis of eye lens dose of the first operator in interventional therapy / 中国辐射卫生

Objective To establish a model for estimating the eye lens dose of the first operator in interventional therapy based on the Monte Carlo simulation, and to provide a scientific basis for the rapid and accurate evaluation of the eye lens dose for radiation workers in interventional therapy. Methods Based on the MIRD phantom and eye model for adult Chinese males, the MCNPX program was used to establish the physical model to calculate the spatial distribution of radiation field and eye lens dose for the first operator. A GR200 Type A LiF (Mg, Cu, P) thermoluminescence dosimeter was used for experimental measurement to verify the simulation results. Results Monte Carlo simulation and experimental measurements showed that the spatial distribution of radiation field was symmetrical. Compared with the measured doses, the errors of the simulated eye lens dose of the first operator were between −8.3% and 7.3%. The dose of the left eye lens was higher than that of the right eye. Conclusion The Monte Carlo model constructed in this study initially realizes the simulation of eye lens dose of the first operator in interventional therapy. In the future, the model will be further optimized based on irradiation parameters such as exposure time, tube voltage, tube current, and projection direction used in clinic practice, so as to more accurately evaluate the eye lens dose of interventional therapy staff.

Monte Carlo design and preliminary test of X-ray protective rubber / 中国辐射卫生

@#<b>Objective</b> To complete the Monte Carlo design and preliminary test of X-ray protective rubber. <b>Methods</b> According to the characteristics of X-ray energy spectrum for interventional therapy, the shielding effects of lead rubber, tungsten and bismuth composite rubber, and gadolinium and bismuth composite rubber samples were calculated by Monte Carlo simulation. The variation law of lead equivalent of lead-free rubber and lead rubber with X-ray peak tube voltage was obtained through actual measurement. <b>Results</b> Within the peak tube voltage range of 60-110 kV, lead-free rubber effectively replaced lead rubber. <b>Conclusion</b> The shielding and attenuation effect of the existing lead-free protective rubber on low-energy stray X-rays is better than that of lead rubber. Considering the inherent defects of lead rubber, flexible X-ray protective materials with thermoplastic elastomer as filler will have broad development prospects.

Influence of reactive oxygen species responsive self-assembled nanomicelle loaded with pyroptosis inhibitor on full-thickness skin defects in diabetic rats / 中华烧伤杂志

Objective: To investigate the influence of reactive oxygen species (ROS) responsive self-assembled nanomicelle loaded with pyroptosis inhibitor on full-thickness skin defects in diabetic rats. Methods: Experimental research methods were employed. A nucleotide-binding oligomerization domain (NOD) 1/2 inhibitor (NOD-IN-1) was encapsulated with nanomicelle polyethylene glycol-block-polypropylene sulfide (PEG-b-PPS), and the resulting product was called PEPS@NOD-IN-1. The morphology and hydration particle size of PEG-b-PPS and PEPS@NOD-IN-1 were observed by transmission electron microscope and particle size analyzer, respectively, and the encapsulation rate and drug loading rate of PEPS@NOD-IN-1 to NOD-IN-1 and the cumulative release rate of NOD-IN-1 by PEPS@NOD-IN-1 in phosphate buffer solution (PBS) alone and hydrogen peroxide-containing PBS within 40 h were measured and calculated by microplate reader, and the sample number was 3. Twenty-four male Sprague-Dawley rats aged 6-7 weeks were injected with streptozotocin to induce type 1 diabetes mellitus. Six full-thickness skin defect wounds were made on the back of each rat. The injured rats were divided into PBS group, NOD-IN-1 group, PEG-b-PPS group, and PEPS@NOD-IN-1 group with corresponding treatment according to the random number table, with 6 rats in each group. The wound healing was observed on post injury day (PID) 3, 7, and 12, and the wound healing rate was calculated. The ROS levels in wound tissue were detected by immunofluorescence method on PID 3. On PID 7, the granulation tissue thickness in wound was assessed by hematoxylin-eosin staining, the mRNA expressions of NOD1 and NOD2 were detected by real-time fluorescence quantitative reverse transcription polymerase chain reaction, and the protein expressions of NOD1, NOD2, and GSDMD-N terminals were detected by Western blotting. Six wounds from different rats in each group were taken for detection of the above indicators. Wound tissue (3 samples per group) was taken from rats in PBS group and PEPS@NOD-IN-1 group on PID 7, and transcriptome sequencing was performed using high-throughput sequencing technology platform. Differentially expressed genes (DEGs) significantly down-regulated in PEPS@NOD-IN-1 group as compared with PBS group were screened, and the enrichment analysis of Kyoto Encyclopedia of Genes and Genomes (KEGG) was performed. The DEG heatmap of the NOD-like receptor pathway, a pyroptosis-related pathway, was made. Protein-protein interaction (PPI) analysis of DEGs in heatmap was performed through the STRING database to screen key genes of PEPS@NOD-IN-1 regulating the NOD-like receptor pathway. Data were statistically analyzed with analysis of variance for repeated measurement, one-way analysis of variance, and Tukey test. Results: PEG-b-PPS and PEPS@NOD-IN-1 were in spherical structures of uniform size, with hydration particle sizes of (134.2±3.3) and (143.1±2.3) nm, respectively. The encapsulation rate of PEPS@NOD-IN-1 to NOD-IN-1 was (60±5)%, and the drug loading rate was (15±3)%. The release of NOD-IN-1 from PEPS@NOD-IN-1 in PBS alone was slow, and the cumulative release rate at 40 h was only (12.4±2.3)%. The release of NOD-IN-1 from PEPS@NOD-IN-1 in hydrogen peroxide-containing PBS within 10 h was very rapid, and the cumulative release rate at 10 h reached (90.1±3.6)%. On PID 3 and 7, the wounds of rats in the four groups were gradually healed, and the healing in PEPS@NOD-IN-1 group was better than that in the other three groups. On PID 12, the wound scab area in PBS group was large, the wound epithelialization in NOD-IN-1 group and PEG-b-PPS group was obvious, and the wound in PEPS@NOD-IN-1 group was close to complete epithelialization. Compared with those in PBS group, NOD-IN-1 group, and PEG-b-PPS group, the wound healing rates on PID 7 and 12 in PEPS@NOD-IN-1 group were significantly increased (P<0.05), the level of ROS in wound tissue on PID 3 was significantly decreased (P<0.05), the thickness of granulation tissue in wound on PID 7 was significantly thickened (P<0.05), and the mRNA expressions of NOD1 and NOD2 and the protein expressions of NOD1, NOD2, and GSDMD-N terminals in wound tissue on PID 7 were significantly decreased (P<0.05). KEGG pathway analysis showed that DEGs significantly down-regulated in PEPS@NOD-IN-1 group as compared with PBS group were significantly enriched in NOD-like receptors, hypoxia-inducible factors, mitogen-activated protein kinases, and tumor necrosis factor (TNF) pathways. In the DEG heatmap of NOD-like receptor pathway, the genes regulating pyroptosis mainly involved NOD1, NOD2, NOD-like receptor thermoprotein domain-related protein 3, Jun, signal transduction and transcriptional activator 1 (STAT1), TNF-α-induced protein 3. The PPI results showed that NOD1, NOD2, and STAT1 were the key genes of PEPS@NOD-IN-1 regulating the NOD-like receptor pathway. Conclusions: PEPS@NOD-IN-1 can down-regulate the level of local ROS in wounds and the expression of NOD1, NOD2, and GSDMD-N terminals, the key regulators of pyroptosis, thereby promoting the repair of full-thickness skin defect wounds in diabetic rats. PEPS@NOD-IN-1 can also significantly down-regulate the pyroptosis, inflammation, and hypoxia-related pathways of wounds, and regulate NOD-like receptor pathways by down-regulating key genes NOD1, NOD2, and STAT1.

Dose-response relationship between age and Streptococcus pneumoniae vaccination coverage in kindergarten children / 中国当代儿科杂志

OBJECTIVES@#To investigate the potential relationship between age and Streptococcus pneumoniae vaccination coverage in kindergarten children, and to provide a basis for guiding vaccination and developing new protein vaccines.@*METHODS@#The stratified cluster random sampling method was used to select 1 830 healthy children from six kindergartens in Shunde District, Foshan City, China, and nasopharyngeal swabs were collected for the isolation and identification of Streptococcus pneumoniae. The logistic regression model based on restricted cubic spline was used to analyze the dose-response relationship between age and Streptococcus pneumoniae vaccination coverage.@*RESULTS@#The rate of nasal Streptococcus pneumoniae carriage was 22.46% (411/1 830) among the kindergarten children, with the predominant serotypes of 6B, 19F, 15A, 23A, 34, and 23F. The coverage rates of 10-valent pneumococcal conjugate vaccine (PCV10) and 13-valent pneumococcal conjugate vaccine (PCV13) were 53.0% and 57.9%, respectively, and there was a significant non-linear dose-response relationship between age and the coverage rates of PCV10 and PCV13 (P<0.05), with a higher coverage rate of PCV10 (88.0%) and PCV13 (91.1%) in the children aged 2 years. There was a significant non-linear dose-response relationship between age and the coverage rates of pilus islet 1 (PI-1) and pilus islet 2 (PI-2) (P<0.05), with a lower vaccination coverage rate for PI-1 (37.7%) and PI-2 (16.1%). The coverage rates of PI-1 (13.0%-58.5%) and PI-2 (6.0%-29.4%) were lower in all age groups. The virulence genes lytA (99.5%) and ply (99.0%) associated with candidate protein vaccines showed higher vaccination coverage rates.@*CONCLUSIONS@#There is a significant non-linear dose-response relationship between the age of kindergarten children and the coverage rates of PCV10 and PCV13 serotypes, and kindergarten children aged 2 years have a relatively high coverage rate of PCV. The high prevalence of the virulence genes lytA and ply shows that they are expected to become candidate virulence factors for the development of a new generation of recombinant protein vaccines.

Implementation and revision of the Measures for the Management of Radiation Workers’ Occupational Health / 中国辐射卫生

Since the implementation of the Measures for the Management of Radiation Workers’ Occupational Health in November 2007, it has played an extremely important role in protecting the occupational health of radiation workers. There are more than 700 000 radiation workers in about 100 000 workplaces with potential radiation exposure, as well as a large number of miners exposed to high levels of radon. As the radiation health monitoring project suggests, measures of occupational health management such as personal dose monitoring and occupational health examination of radiation workers have been widely implemented and achieved good results in the protection of radiation workers. However, the risks of chromosomal aberration and specific turbidity of the eye lens of radiation workers have increased in high-risk positions such as interventional radiology, nuclear medicine, and industrial flaw detection. The control of high radon exposure in miners needs to be strengthened. It is necessary to adapt to the new situation in view of new challenges and actively promote the revision of the Measures for the Management of Radiation Workers’ Occupational Health, so as to further improve the occupational health management of radiation workers in China.

Development and validation of a noninvasive prediction model for identifying eosinophilic asthma.

BACKGROUND: Identification of eosinophilic asthma (EA) using sputum analysis is important for disease monitoring and individualized treatment. But it is laborious and technically demanding. We aimed to develop and validate an effective model to predict EA with multidimensional assessment (MDA). METHODS: The asthma patients who underwent a successful sputum induction cytological analysis were consecutively recruited from March 2014 to January 2021. The variables assessed by MDA were screened by least absolute shrinkage and selection operator (LASSO) and logistic regression to develop a nomogram and an online web calculator. Validation was performed internally by a bootstrap sampling method and externally in the validation cohort. Diagnostic accuracy of the model in different asthma subgroups were also investigated. RESULTS: In total of 304 patients in the training cohort and 95 patients in the validation cohort were enrolled. Five variables were identified in the EA prediction model: gender, nasal polyp, blood eosinophils, blood basophils and FeNO. The C-index of the model was 0.86 (95% CI: 0.81-0.90) in the training cohort and 0.84 (95% CI: 0.72-0.89) in the validation cohort. The calibration curve showed good agreement between the prediction and actual observation. The decision curve analysis (DCA) also demonstrated that the EA prediction model was clinically beneficial. An online publicly available web calculator was constructed (https://asthmaresearcherlimin.shinyapps.io/DynNomapp/). CONCLUSION: We developed and validated a multivariable model based on MDA to help the diagnosis of EA, which has good diagnostic performance and clinical practicability. This practical tool may be a useful alternative for predicting EA in the clinic.

Structural and biochemical mechanism for increased infectivity and immune evasion of Omicron BA.1 and BA.2 variants and their mouse origins

The Omicron BA.2 variant has become a dominant infective strain worldwide. Receptor binding studies reveal that the Omicron BA.2 spike trimer have 11-fold and 2-fold higher potency to human ACE2 than the spike trimer from the wildtype (WT) and Omicron BA.1 strains. The structure of the BA.2 spike trimer complexed with human ACE2 reveals that all three receptor-binding domains (RBDs) in the spike trimer are in open conformation, ready for ACE2 binding, thus providing a basis for the increased infectivity of the BA.2 strain. JMB2002, a therapeutic antibody that was shown to have efficient inhibition of Omicron BA.1, also shows potent neutralization activities against Omicron BA.2. In addition, both BA.1 and BA.2 spike trimers are able to bind to mouse ACE2 with high potency. In contrast, the WT spike trimer binds well to cat ACE2 but not to mouse ACE2. The structures of both BA.1 and BA.2 spike trimer bound to mouse ACE2 reveal the basis for their high affinity interactions. Together, these results suggest a possible evolution pathway for Omicron BA.1 and BA.2 variants from human-cat-mouse-human circle, which could have important implications in establishing an effective strategy in combating viral infection.

Molecular mechanism of Ganoderma against gastric cancer based on network pharmacology and experimental test / 中国中药杂志

This study aims to explore the molecular mechanism of Ganoderma against gastric cancer based on network pharmacology, molecular docking, and cell experiment. The active components and targets of Ganoderma were retrieved from Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP), and gastric cancer-related targets from GeneCards and Online Mendelian Inheritance in Man(OMIM). The protein-protein interaction(PPI) network of the common targets was constructed with STRING, followed by Gene Ontology(GO) term enrichment and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment analysis of the common genes based on Bioconductor and R language. The medicinal-disease-component-target network and medicinal-disease-component-target-pathway network were established by Cytoscape. Molecular docking was performed between β-sitosterol(the key component in Ganoderma) and the top 15 targets in the PPI network. Cell experiment was performed to verify the findings. A total of 14 active components and 28 targets of Ganoderma were retrieved, and the medicinal and the disease shared 25 targets, including caspase-3(CASP3), caspase-8(CASP8), caspase-9(CASP9), and B-cell lymphoma-2(BCL2). The common targets involved 72 signaling pathways and apoptosis and p53 signaling pathway may play a crucial role in the effect of Ganoderma against gastric cancer. β-sitosterol had strong binding activity to the top 15 targets in the PPI network. The in vitro cell experiment demonstrated that β-sitosterol inhibited gastric cancer AGS cell proliferation by inducing cell apoptosis and cell cycle arrest in the S phase, which might be related to the regulation of the p53 pathway. This study shows the multi-component, multi-target, and multi-pathway characteristics of Ganoderma against gastric cancer, which lays a scientific basis for further research on the molecular mechanism.

Preliminary study on dicentric chromosome identification algorithm based on artificial intelligence technology / 中华放射医学与防护杂志

Objective:To explore artificial intelligence technology and propose an algorithm for automatic identification of dicentric chromosomes to realize fast and high-throughput biodosimetry. In order to solve the time-consuming and laborious problem of manual analysis of dicentric chromosomes.Methods:Combining artificial intelligence technology and image processing technology, based on MATLAB software, algorithms like image preprocessing, threshold segmentation algorithm, binarization processing, area identification algorithm, convolutional neural network algorithm and double centripetal recognition algorithm were applied. A fuzzy membership function was defined to describe the degree of each chromosome belonging to a dicentric chromosome, and the discrimination threshold was set to realize the automatic identification of dicentric chromosomes.Results:Through the test on 1 471 chromosome images, compared with manual recognition, the detection rate of dicentric chromosomes cells of this algorithm reached 70.7%.Conclusions:This algorithm method carries out a preliminary study on the automatic identification of dicentric chromosomes with good result.

Two decomposition algorithms of dual-energy cone beam CT and their dependence on the phantom sizes / 中华放射医学与防护杂志

Objective:To analyze the effects of two decomposition algorithms of dual-energy cone beam CT (DECBCT) (direct decomposition and iterative decomposition) on the image quality and material decomposition accuracy of different sizes of phantoms.Methods:Different sizes of imaging parts of patients were simulated using the combination of CatPhan604 phantoms and customized annuluses. CBCT with high energy of 140 kVp and low energy of 100 kVp were acquired using the Varian Edge CBCT system. Then the material decomposition of DECBCT images was performed using the two algorithms. The electron density (ED) and contrast-to-noise ratio (CNR) of each material in the CTP682 module were calculated. They were used to assess the decomposition accuracy and image quality of the two algorithms.Results:Based on the values in the Catphan604 manual, both algorithms have high ED accuracy. Only the ED accuracy of four materials of the smallest sized phantom showed statistical difference ( z = -4.21, 4.30, 2.87, 5.45, P < 0.05), but the average relative error was less than 1%. The CNR of the iterative decomposition algorithm was significantly higher than that of the direct decomposition, increasing by 51.8%-703.47%. The increase in the phantom size significantly reduced the accuracy of ED, and the increased amplitude of the relative error was up to a maximum of 2.52%. The large phantom size also reduced the image quality of iterative decomposition, and the decreased amplitude of CNR was up to a maximum of 39.71. Conclusions:Compared with the direct decomposition, the iterative decomposition algorithm can significantly reduce the image noise and improve the contrast without losing the accuracy of electron density in the DECBCT construction of different sizes of phantoms.

An EHG-based Preterm Delivery Prediction Algorithm via Convolution Neural Network / 中国医疗器械杂志

Premature delivery is one of the direct factors that affect the early development and safety of infants. Its direct clinical manifestation is the change of uterine contraction intensity and frequency. Uterine Electrohysterography(EHG) signal collected from the abdomen of pregnant women can accurately and effectively reflect the uterine contraction, which has higher clinical application value than invasive monitoring technology such as intrauterine pressure catheter. Therefore, the research of fetal preterm birth recognition algorithm based on EHG is particularly important for perinatal fetal monitoring. We proposed a convolution neural network(CNN) based on EHG fetal preterm birth recognition algorithm, and a deep CNN model was constructed by combining the Gramian angular difference field(GADF) with the transfer learning technology. The structure of the model was optimized using the clinical measured term-preterm EHG database. The classification accuracy of 94.38% and F1 value of 97.11% were achieved. The experimental results showed that the model constructed in this paper has a certain auxiliary diagnostic value for clinical prediction of premature delivery.

Current situation and analysis of radiological diagnosis and treatment resources in Inner Mongolia Autonomous Region, China, 2019 / 中国辐射卫生

Objective To comprehensively obtain the present situation of medical radiation protection resources by investigating the basic information of all medical institutions in Inner Mongolia Autonomous Region, China from 2017 to 2019. Methods An investigation was conducted on the basic information of medical institutions according to the unified plan of medical radiation protection monitoring project issued in Inner Mongolia Autonomous Region, involving all radiodiagnostic medical institutions throughout the region. Results By the end of 2019, there were 1195 radiological diagnosis and treatment institutions, 7285 radiation workers, 2705 sets of radiological diagnostic equipment, 36 medical accelerators, and 22 sets of nuclear medicine equipment in the whole region. Conclusion The radiological diagnosis and treatment resources in Inner Mongolia Autonomous Region are developing rapidly. However, the problems of insufficient per capita resources and uneven development among the cities are becoming increasingly prominent.

Optimal recognition algorithm for solid nuclear track images based on morphology and machine learning / 中国辐射卫生

Objective To propose a computer recognition algorithm for solid nuclear track images based on the machine learning method, and to realize the automatic, fast and accurate recognition of nuclear tracks and improve the efficiency of solid track image analysis. Methods Firstly, 143 images containing tracks were scanned by morphological method to determine the location of suspected tracks, and 1250 material images were captured. 50% of the material were selected as the training set and 30% as the validation set for training the machine learning model. Another 20% of the material were selected as the test set for testing the model recognition result. The algorithm code was written and trained based on the MATLAB software. Results The established solid track recognition algorithm had a strong recognition capability, and the recognition accuracy of the test set could reach 84.8%. The machine learning model program constructed by the algorithm could evolve continuously with the input of training data, further improving the accuracy. Conclusion Based on image morphology and machine learning, the track recognition algorithm was investigated, by which the automatic recognition of solid tracks was better realized. In the future, we will increase the data input of the model, optimize the algorithm, and improve the recognition accuracy, in order to provide a more accurate and efficient method for automatic image track recognition.