Evading host immunity killing is a critical step for virus survival. Inhibiting viral immune escape is crucial for the treatment of viral diseases. Serine/threonine kinase 39 (STK39) was reported to play an essential role in ion homeostasis. However, its potential role and mechanism in viral infection remain unknown. In this study, we found that viral infection promoted STK39 expression. Consequently, overexpressed STK39 inhibited the phosphorylation of interferon regulatory factor 3 (IRF3) and the production of type I interferon, which led to viral replication and immune escape. Genetic ablation or pharmacological inhibition of STK39 significantly protected mice from viral infection. Mechanistically, mass spectrometry and immunoprecipitation assays identified that STK39 interacted with PPP2R1A (a scaffold subunit of protein phosphatase 2A (PP2A)) in a kinase activity-dependent manner. This interaction inhibited DDB1 and CUL4 associated factor 1 (DCAF1)-mediated PPP2R1A degradation, maintained the stabilization and phosphatase activity of PP2A, which, in turn, suppressed the phosphorylation of IRF3, decreased the production of type I interferon, and then strengthened viral replication. Thus, our study provides a novel theoretical basis for viral immune escape, and STK39 may be a potential therapeutic target for viral infectious diseases.

Objective:To investigate the expulsion rate of GyneFix postpartum intrauterine device (PPIUD) placed immediately after cesarean section within one year and its influencing factors.Methods:A prospective cohort study was conducted. Women who volunteered to use a GyneFix PPIUD placed immediately after cesarean section (within 10 min after placenta delivery) for postpartum contraception were recruited from September 2017 to November 2020. The relevant information was collected through questionnaires before, during and 24 h after cesarean section. Outpatient follow-up was conducted at 42 d, 3 months, 6 months and 12 months after delivery to obtain information on expulsion of GyneFix PPIUD and unwanted pregnancy. Life table and Cox regression model were used to analyze the cumulative expulsion rate and related influencing factors.Results:A total of 470 subjects were recruited and 461 (98%) subjects were eligible for this study. The cumulative expulsion rate of GyneFix PPIUD within one year after cesarean section was 8.4% (95% CI: 7.0%-9.8%). Multivariate Cox regression analysis showed that women aged >35 years had significantly lower risk of PPIUD expulsion than those aged <25 years ( HR=0.16, 95% CI: 0.04-0.64). The risk of GyneFix PPIUD was not statistically significantly associated with cesarean section history and breastfeeding mode (all P>0.05). Nevertheless, this risk was statistically significant between hospitals. The Pearl index of contraceptive failure of the device was 2.37 (95% CI: 1.09-4.50) per 100 person-years. The rate of contraceptive failure was not associated with maternal age, breastfeeding mode, and history of cesarean delivery (all P>0.05). Conclusion:The one-year cumulative expulsion rate of GyneFix PPIUD placed immediately after cesarean section is 8.4%. Young mothers were at a higher risk of expulsion than their older counterparts. The device users should be counseled regarding the signs of expulsion. In case of expulsion, women should be offered reinsertion or other contraceptive methods. The training of service skills of GyneFix PPIUD should be strengthened in order to mitigate the risk of the device expulsion.

The wide use of crystalline silicon solar cells in the field of new energy is an important boost for China to achieve the environmental protection goal as soon as possible. However, the production and manufacturing processes of these cells give rise to various occupational hazards at workplace, thus posing health risks to workers. This review provided an overview of production processes of crystalline silicon solar cells, the characteristics of occupational health hazards (productive dust; physical factors, productive toxicant) and proposed occupational protection suggestions.

The wide use of crystalline silicon solar cells in the field of new energy is an important boost for China to achieve the environmental protection goal as soon as possible. However, the production and manufacturing processes of these cells give rise to various occupational hazards at workplace, thus posing health risks to workers. This review provided an overview of production processes of crystalline silicon solar cells, the characteristics of occupational health hazards (productive dust; physical factors, productive toxicant) and proposed occupational protection suggestions.

Objective:To investigate the expulsion rate of GyneFix postpartum intrauterine device (PPIUD) placed immediately after cesarean section within one year and its influencing factors.Methods:A prospective cohort study was conducted. Women who volunteered to use a GyneFix PPIUD placed immediately after cesarean section (within 10 min after placenta delivery) for postpartum contraception were recruited from September 2017 to November 2020. The relevant information was collected through questionnaires before, during and 24 h after cesarean section. Outpatient follow-up was conducted at 42 d, 3 months, 6 months and 12 months after delivery to obtain information on expulsion of GyneFix PPIUD and unwanted pregnancy. Life table and Cox regression model were used to analyze the cumulative expulsion rate and related influencing factors.Results:A total of 470 subjects were recruited and 461 (98%) subjects were eligible for this study. The cumulative expulsion rate of GyneFix PPIUD within one year after cesarean section was 8.4% (95% CI: 7.0%-9.8%). Multivariate Cox regression analysis showed that women aged >35 years had significantly lower risk of PPIUD expulsion than those aged <25 years ( HR=0.16, 95% CI: 0.04-0.64). The risk of GyneFix PPIUD was not statistically significantly associated with cesarean section history and breastfeeding mode (all P>0.05). Nevertheless, this risk was statistically significant between hospitals. The Pearl index of contraceptive failure of the device was 2.37 (95% CI: 1.09-4.50) per 100 person-years. The rate of contraceptive failure was not associated with maternal age, breastfeeding mode, and history of cesarean delivery (all P>0.05). Conclusion:The one-year cumulative expulsion rate of GyneFix PPIUD placed immediately after cesarean section is 8.4%. Young mothers were at a higher risk of expulsion than their older counterparts. The device users should be counseled regarding the signs of expulsion. In case of expulsion, women should be offered reinsertion or other contraceptive methods. The training of service skills of GyneFix PPIUD should be strengthened in order to mitigate the risk of the device expulsion.

Computer-aided diagnosis (CAD) systems play a very important role in modern medical diagnosis and treatment systems, but their performance is limited by training samples. However, the training samples are affected by factors such as imaging cost, labeling cost and involving patient privacy, resulting in insufficient diversity of training images and difficulty in data obtaining. Therefore, how to efficiently and cost-effectively augment existing medical image datasets has become a research hotspot. In this paper, the research progress on medical image dataset expansion methods is reviewed based on relevant literatures at home and abroad. First, the expansion methods based on geometric transformation and generative adversarial networks are compared and analyzed, and then improvement of the augmentation methods based on generative adversarial networks are emphasized. Finally, some urgent problems in the field of medical image dataset expansion are discussed and the future development trend is prospected.
Humans ; Diagnosis, Computer-Assisted ; Diagnostic Imaging ; Datasets as Topic

Objective:To study the distribution and antibiotics resistance of the main pathogens of neonatal purulent meningitis in different regions of China.Methods:A retrospective descriptive clinical epidemiological study was conducted in children with neonatal purulent meningitis which admitted to 18 tertiary hospitals in different regions of China between January 2015 to December 2019. The test results of blood and cerebrospinal fluid, and drug sensitivity test results of the main pathogens were collected. The distributions of pathogenic bacteria in children with neonatal purulent meningitis in preterm and term infants, early and late onset infants, in Zhejiang Province and other regions outside Zhejiang Province, and in Wenzhou region and other regions of Zhejiang Province were analyzed. The chi-square test was used for statistical analysis.Results:A total of 210 neonatal purulent meningitis cases were collected. The common pathogens were Escherichia coli ( E. coli)(41.4%(87/210)) and Streptococcus agalactiae ( S. agalactiae)(27.1%(57/210)). The proportion of Gram-negative bacteria in preterm infants (77.6%(45/58)) with neonatal purulent meningitis was higher than that in term infants (47.4%(72/152)), and the difference was statistically significant ( χ2=15.54, P=0.001). There were no significant differences in the constituent ratios of E. coli (36.5%(31/85) vs 44.8%(56/125)) and S. agalactiae (24.7%(21/85) vs 28.8%(36/125)) between early onset and late onset cases (both P>0.05). The most common pathogen was E. coli in different regions, with 46.7%(64/137) in Zhejiang Province and 31.5%(23/73) in other regions outside Zhejiang Province. In Zhejiang Province, S. agalactiae was detected in 49 out of 137 cases (35.8%), which was significantly higher than other regions outside Zhejiang Province (11.0%(8/73)). The proportions of Klebsiella pneumoniae, and coagulase-negative Staphylococcus in other regions outside Zhejiang Province (17.8%(13/73) and 16.4%(12/73)) were both higher than those in Zhejiang Province (2.9%(4/137) and 5.1%(7/137)). The differences were all statistically significant ( χ2=14.82, 12.26 and 7.43, respectively, all P<0.05). The proportion of Gram-positive bacteria in Wenzhou City (60.8%(31/51)) was higher than that in other regions in Zhejiang Province (38.4%(33/86)), and the difference was statistically significant ( χ2=6.46, P=0.011). E. coli was sensitive to meropenem (0/45), and 74.4%(32/43) of them were resistant to ampicillin. E. coli had different degrees of resistance to other common cephalosporins, among which, cefotaxime had the highest resistance rate of 41.8%(23/55), followed by ceftriaxone (32.4%(23/71)). S. agalactiae was sensitive to penicillin, vancomycin and linezolid. Conclusions:The composition ratios of pathogenic bacteria of neonatal purulent meningitis are different in different regions of China. The most common pathogen is E. coli, which is sensitive to meropenem, while it has different degrees of resistance to other common cephalosporins, especially to cefotaxime.

Medical image segmentation based on deep learning has become a powerful tool in the field of medical image processing. Due to the special nature of medical images, image segmentation algorithms based on deep learning face problems such as sample imbalance, edge blur, false positive, false negative, etc. In view of these problems, researchers mostly improve the network structure, but rarely improve from the unstructured aspect. The loss function is an important part of the segmentation method based on deep learning. The improvement of the loss function can improve the segmentation effect of the network from the root, and the loss function is independent of the network structure, which can be used in various network models and segmentation tasks in plug and play. Starting from the difficulties in medical image segmentation, this paper first introduces the loss function and improvement strategies to solve the problems of sample imbalance, edge blur, false positive and false negative. Then the difficulties encountered in the improvement of the current loss function are analyzed. Finally, the future research directions are prospected. This paper provides a reference for the reasonable selection, improvement or innovation of loss function, and guides the direction for the follow-up research of loss function.
Algorithms ; Image Processing, Computer-Assisted

Hepatitis B virus core protein can self-assemble into icosahedral symmetrical viral-like particles (VLPs) in vitro, and display exogenous sequences repeatedly and densely on the surface. VLPs also have strong immunogenicity and biological activity. When the nanoparticles enter the body, they quickly induce specific humoral and cellular immune responses to exogenous antigens. In this study, we designed an HBc-VLPs that can be coupled with antigens at specific sites, and developed a set of efficient methods to prepare HBc-VLPs. Through site-specific mutation technology, the 80th amino acid of peptide was changed from Ala to Cys, a specific cross-linking site was inserted into the main immunodominant region of HBc-VLPs, and the prokaryotic expression vector pET28a(+)-hbc was constructed. After expression and purification, high purity HBc(A80C) monomer protein was assembled into HBc-VLPs nanoparticles in Phosphate Buffer. The results of particle size analysis show that the average particle size of nanoparticles was 29.8 nm. Transmission electron microscopy (TEM) showed that HBc-VLPs formed spherical particles with a particle size of about 30 nm, and its morphology was similar to that of natural HBV particles. The influenza virus antigen M2e peptide as model antigen was connected to Cys residue of HBc-VLPs by Sulfo-SMCC, an amino sulfhydryl bifunctional cross-linking agent, and M2e-HBc-VLPs model vaccine was prepared. The integrity of HBc-VLPs structure and the correct cross-linking of M2e were verified by cell fluorescence tracing. Animal immune experiments showed that the vaccine can effectively stimulate the production of antigen-specific IgG antibody in mice, which verified the effectiveness of the vaccine carrier HBc-VLPs. This study lays a foundation for the research of HBc-VLPs as vaccine vector, and help to promote the development of HBc-VLPs vaccine and the application of HBc-VLPs in other fields.
Animals ; Hepatitis B Core Antigens ; genetics ; immunology ; Immunity, Cellular ; immunology ; Immunoglobulin G ; blood ; Mice ; Mice, Inbred BALB C ; Vaccines, Virus-Like Particle ; genetics ; immunology

Objective? To analyze the mediating and modulating effects of self-efficacy between health literacy and quality of life in patients with esophagus cancer receiving chemotherapy. Methods? Totally 105 patients receiving chemotherapy for esophagus cancer in Heping Hospital Affiliated to Changzhi Medical University from January 2015 to December 2017 were selected by convenient sampling and investigated with General Self Efficacy Scale (GSES), Health Literacy Management Scale (HeLMS) and Spitzer Quality of Life Index (SQLI). Pearson correlation analysis was used to analyze the correlation between the patients' self-efficacy, health literacy and quality of life, and regression analysis was used to mediating and modulating effects between the variables. Results? The average self-efficacy score, health literacy score and quality of life score of the 105 patients were (2.38±0.47), (86.65±12.29) and (4.94±0.55), respectively. Pearson correlation analysis showed that self-efficacy was positively correlated with health literacy and quality of life (r=0.517, 0.462; P＜0.05). Self-efficacy showed mediating effects between health literacy and quality of life in the patients with esophagus cancer, which accounted for 34.82% in the total effect. Regression analysis showed that the regression coefficient of the interacting "health literacy×self-efficacy" was statistically significant (β'=0.015,t=2.718;P＜ 0.01), whose mediating effect was significant (ΔR2=0.018, P＜ 0.01). Conclusions? Self-efficacy has mediating and modulating effects between health literacy and quality of life in patients receiving chemotherapy for esophagus cancer.