Optimal ultrasonic treatment frequency and duration parameters were used to detect the pathogenic bacteria of orthopedic implant-associated infection by ultrasonic oscillation.

INTRUDUCTON: The most accurate method for detecting the pathogen of orthopedic implant-associated infections (OIAIs) is sonication fluid (SF). However, the frequency and duration of ultrasound significantly influence the number and activity of microorganisms. Currently, there is no consensus on the selection of these two parameters. Through this study, the choice of these two parameters is clarified. METHODS: We established five ultrasonic groups (40kHz/10min, 40kHz/5min, 40 kHz/1min, 20kHz/5min, and 10kHz/5min) based on previous literature. OIAIs models were then developed and applied to ultrasound group treatment. Subsequently, we evaluated the efficiency of bacteria removal by conducting SEM and crystal violet staining. The number of live bacteria in the SF was determined using plate colony count and live/dead bacteria staining. RESULTS: The results of crystal violet staining revealed that both the 40kHz/5min group and the 40kHz/10min group exhibited a significantly higher bacterial clearance rate compared to the other groups. However, there was no significant difference between the two groups. Additionally, the results of plate colony count and fluorescence staining of live and dead bacteria indicated that the number of live bacteria in the 40kHz/5min SF group was significantly higher than in the other groups. CONCLUSION: 40kHz/5min ultrasound is the most beneficial for the detection of pathogenic bacteria on the surface of orthopedic implants.

Combining sequence and network information to enhance protein-protein interaction prediction.

BACKGROUND: Protein-protein interactions (PPIs) are of great importance in cellular systems of organisms, since they are the basis of cellular structure and function and many essential cellular processes are related to that. Most proteins perform their functions by interacting with other proteins, so predicting PPIs accurately is crucial for understanding cell physiology. RESULTS: Recently, graph convolutional networks (GCNs) have been proposed to capture the graph structure information and generate representations for nodes in the graph. In our paper, we use GCNs to learn the position information of proteins in the PPIs networks graph, which can reflect the properties of proteins to some extent. Combining amino acid sequence information and position information makes a stronger representation for protein, which improves the accuracy of PPIs prediction. CONCLUSION: In previous research methods, most of them only used protein amino acid sequence as input information to make predictions, without considering the structural information of PPIs networks graph. We first time combine amino acid sequence information and position information to make representations for proteins. The experimental results indicate that our method has strong competitiveness compared with several sequence-based methods.

Effective norm emergence in cell systems under limited communication.

BACKGROUND: The cooperation of cells in biological systems is similar to that of agents in cooperative multi-agent systems. Research findings in multi-agent systems literature can provide valuable inspirations to biological research. The well-coordinated states in cell systems can be viewed as desirable social norms in cooperative multi-agent systems. One important research question is how a norm can rapidly emerge with limited communication resources. RESULTS: In this work, we propose a learning approach which can trade off the agents' performance of coordinating on a consistent norm and the communication cost involved. During the learning process, the agents can dynamically adjust their coordination set according to their own observations and pick out the most crucial agents to coordinate with. In this way, our method significantly reduces the coordination dependence among agents. CONCLUSION: The experiment results show that our method can efficiently facilitate the social norm emergence among agents, and also scale well to large-scale populations.

Construction of a hepatocellular carcinoma high-risk population rating scale and independent predictors' assessment.

BACKGROUND: With increasing mortality and incidence, hepatocellular carcinoma (HCC) has become a major public health problem. The early diagnosis of HCC can improve its prognosis. The aim of this study was to identify potential risk factors related to HCC development and to establish a high-risk population rating scale. METHODS: A total of 853 patients with chronic hepatitis B (CHB) were enrolled in this study, including 403 patients with HCC as the case group and others as the control group. Their demographic and clinical characteristics were compared and the independent risk factors for HCC were assessed. Then, the optimal cutoff levels of these factors were analyzed by the receiver operating characteristic (ROC) method. A high-risk population rating scale was constructed based on the factors and then evaluated in the modeling population. RESULTS: The factors that presented statistically significant differences between the two groups included age, smoking, alcohol abuse, body mass index, triglyceride, high‒density lipoprotein cholesterol, aspartate transaminase, alanine transaminase, fasting plasma glucose, creatinine and uric acid. The ROC curve showed that the cutoff score for the HCC high risk population was 5 (AUC=0.74, P<0.001) and the Hosmer‒Lemeshow analysis showed that the fitting effect of this rating scale was good (P = 0.294). CONCLUSIONS: The integration of these factors can contribute to a prognostic score for the risk of HCC development, which offered certain clinical practicability.

Analysis of risk factors and development of a nomogram-based prediction model for defective bony non-union.

Objective: To explore risk factors for defective non-union of bone and develop a nomogram-based prediction model for such an outcome. Methods: This retrospective study analysed the case data of patients with defective bony non-unions who were treated at the authors' hospital between January 2010 and December 2020. Patients were divided into the union and non-union groups according to their Radiographic Union Score for Tibia scores 1 year after surgery. Univariate analysis was performed to assess factors related to demographic characteristics, laboratory investigations, surgery, and trauma in both groups. Subsequently, statistically significant factors were included in the multivariate logistic regression analysis to identify independent risk factors. A nomogram-based prediction model was established using statistically significant variables in the multivariate analysis. The accuracy and stability of the model were evaluated using receiver operating characteristic (ROC) and calibration curves. The clinical applicability of the nomogram model was evaluated using decision curve analysis. Results: In total, 204 patients (171 male, 33 female; mean [±SD] age, 39.75 ± 13.00 years) were included. The mean body mass index was 22.95 ± 3.64 kg/m2. Among the included patients, 29 were smokers, 18 were alcohol drinkers, and 21 had a previous comorbid systemic disease (PCSD). Univariate analysis revealed that age, occupation, PCSD, smoking, drinking, interleukin-6, C-reactive protein (CRP), procalcitonin, alkaline phosphatase, glucose, and uric acid levels; blood calcium ion concentration; and bone defect size (BDS) were correlated with defective bone union (all P < 0.05). Multivariate logistic regression analysis revealed that PCSD, smoking, interleukin-6, CRP, and glucose levels; and BDS were associated with defective bone union (all P < 0.05), and the variables in the multivariate analysis were included in the nomogram-based prediction model. The value of the area under the ROC curve for the predictive model for bone defects was 0.95. Conclusion: PCSD, smoking, interleukin-6, CRP, and glucose levels; and BDS were independent risk factors for defective bony non-union, and the incidence of such non-union was predicted using the nomogram. These findings are important for clinical interventions and decision-making.

Preliminary investigation of hepatitis E virus detection by a recombinase polymerase amplification assay combined with a lateral flow strip.

Hepatitis E virus (HEV) is a zoonotic pathogen that is a significant public health problem. Detecting HEV relies mainly on conventional PCR, which is time-consuming and requires sophisticated instruments and trained staff. We aimed to establish a reverse-transcription (RT)-recombinase polymerase amplification (RPA) assay (RT-RPA) combined with a lateral flow strip (LFS; RT-RPA-LFS) to rapidly detect HEV RNA in human and rabbit samples. With the optimal reaction conditions (37°C for 30 min), our assay detected as few as 1.0 × 102 copies/mL of HEV and showed no cross-reactivity with other hepatitis viruses. We tested 28 human samples (4 fecal and 24 serum samples) and 360 rabbit samples (180 fecal and 180 serum samples) with our RT-RPA-LFS assay and compared our assay to an RT-qPCR method. There was no significant difference (p > 0.05) in the test results between the 2 assays. Our RT-RPA-LFS assay detected both HEV3 and HEV4 genotypes. Our rapid, sensitive, and specific RT-RPA-LFS assay for the detection of HEV may provide a useful detection tool for limited-resource areas.

Establishment and Characterization of the First Chinese National Standard for Nucleic Acid Amplification Technology Assays for Hepatitis E Virus Nucleic Acid Detection.

The detection of hepatitis E virus (HEV) RNA is the gold standard for HEV infection diagnosis. In order to address the quality control requirements for HEV RNA detection kits within China, we aimed to establish the first Chinese national standard for HEV RNA detection through a collaborative study. The candidate standard was quantified using digital PCR (dPCR). A total of five laboratories were invited to determine the estimated mean value of this national standard relative to the World Health Organization International Standard (WHO IS). Additionally, four commercial kits were used to assess the applicability of the candidate standard. The stability was determined by freeze-thaw cycles and storage at 37 °C, 25 °C and 4 °C. The estimated mean value of this national standard relative to the WHO IS was 5.67 log10 IU/mL. Two out of the four commercial kits can detect as low as the estimated limit of detection (LOD). The degradation rates of samples in the stability study ranged from 4% to 19%. In conclusion, we have established the first Chinese national standard for HEV nucleic acid detection against WHO IS, which can be employed to evaluate the quality of HEV RNA detection kits.

Non-small cell lung cancers (NSCLCs) oncolysis using coxsackievirus B5 and synergistic DNA-damage response inhibitors.

With the continuous in-depth study of the interaction mechanism between viruses and hosts, the virus has become a promising tool in cancer treatment. In fact, many oncolytic viruses with selectivity and effectiveness have been used in cancer therapy. Human enterovirus is one of the most convenient sources to generate oncolytic viruses, however, the high seroprevalence of some enteroviruses limits its application which urges to exploit more oncolytic enteroviruses. In this study, coxsackievirus B5/Faulkner (CV-B5/F) was screened for its potential oncolytic effect against non-small cell lung cancers (NSCLCs) through inducing apoptosis and autophagy. For refractory NSCLCs, DNA-dependent protein kinase (DNA-PK) or ataxia telangiectasia mutated protein (ATM) inhibitors can synergize with CV-B5/F to promote refractory cell death. Here, we showed that viral infection triggered endoplasmic reticulum (ER) stress-related pro-apoptosis and autophagy signals, whereas repair for double-stranded DNA breaks (DSBs) contributed to cell survival which can be antagonized by inhibitor-induced cell death, manifesting exacerbated DSBs, apoptosis, and autophagy. Mechanistically, PERK pathway was activated by the combination of CV-B5/F and inhibitor, and the irreversible ER stress-induced exacerbated cell death. Furthermore, the degradation of activated STING by ERphagy promoted viral replication. Meanwhile, no treatment-related deaths due to CV-B5/F and/or inhibitors occurred. Conclusively, our study identifies an oncolytic CV-B5/F and the synergistic effects of inhibitors of DNA-PK or ATM, which is a potential therapy for NSCLCs.

Prognostic Factors and Clinical Characteristics of Chronic Hepatitis B with or without Nucleos(t)ide Analogues Therapy: A Retrospective Study.

OBJECTIVE: We compared the prognostic factors and clinical characteristics of chronic hepatitis B (CHB) patients who received nucleos(t)ide analogues (NAs) therapy to those who did not. METHOD: A total of 315 CHB patients were enrolled in this study and were divided into NA (n=144) and non-NA (n=171) groups based on their therapy. RESULTS: The risk of hepatocellular carcinoma (HCC) development and mortality in the NA group were significantly lower than those in the non-NA group. Smoking, alcohol abuse, AFP, γ-GTP, and HBV DNA levels were significantly correlated with hepatocarcinogenesis. Alcohol abuse, AFP, γ-GTP, HBV DNA levels and NA treatment were associated with mortality in these patients. CONCLUSIONS: NA therapy reduced the risk of HCC and mortality in CHB patients. Smoking, alcohol abuse, AFP >20 ng/mL, HBV DNA >20,000 IU/mL, and elevated γ-GTP serum concentration were significantly related to poor outcomes.

Investigation of genotype diversity of 7,804 norovirus sequences in humans and animals of China.

Norovirus is a prominent enteric virus responsible for severe acute gastroenteritis disease burden worldwide. In our current study, we analyzed 7,804 norovirus sequences of human and animals in China which were detected from 1980 to 2020 from GenBank. The GenBank database was searched up to May 2021 with the following search terms: "norovirus" or "norwalk virus" and "China." The 7,804 norovirus sequences were collected and evaluated by phylogenetic analysis using MEGA X software package. The online typing tool (https://www.rivm.nl/mpf/typingtool/norovirus/) was used to confirm the genotypes. There were 36 norovirus genotypes prevailing in China. GII.4 was the most prevalent genotype, and GII.2, GII.3 and GII.17 also emerged during different time periods. Most sequences were detected in East China (41.72%, 3,256/7,804), but different norovirus genotypes were distributed widely across the country. A variety of norovirus genotypes, including GI, GII, GIII, GIV, GV, GVI, GVII and GX, were reported in different animals. Furthermore, a GI.3 sequence detected from animal had high identity with norovirus detected in human from the same region, indicating the potential norovirus zoonotic transmission in China. In conclusion, these results indicated that norovirus sequences with considerable genetic diversity distributed widely in China, with potential reverse zoonotic transmission from human to animals.

A 3D bioprinted nano-laponite hydrogel construct promotes osteogenesis by activating PI3K/AKT signaling pathway.

Development of nano-laponite as bioinks based on cell-loaded hydrogels has recently attracted significant attention for promoting bone defect repairs and regeneration. However, the underlying mechanisms of the positive function of laponite in hydrogel was not fully explored. In this study, the effect of 3D bioprinted nano-laponite hydrogel construct on bone regeneration and the potential mechanism was explored in vitro and in vivo. In vitro analyses showed that the 3D construct protected encapsulated cells from shear stresses during bioprinting, promoted cell growth and cell spreading, and BMSCs at a density of 107/mL exhibited an optimal osteogenesis potential. Osteogenic differentiation and ectopic bone formation of BMSCs encapsulated inside the 3D construct were explored by determination of calcium deposition and x-ray, micro-CT analysis, respectively. RNA sequencing revealed that activation of PI3K/AKT signaling pathway of BMSCs inside the laponite hydrogel significantly upregulated expression of osteogenic related proteins. Expression of osteogenic proteins was significantly downregulated when the PI3K/AKT pathway was inhibited. The 3D bioprinted nano-laponite hydrogel construct exhibited a superior ability for bone regeneration in rat bones with defects compared with groups without laponite as shown by micro-CT and histological examination, while the osteogenesis activity was weakened by applications of a PI3K inhibitor. In summary, the 3D bioprinted nano-laponite hydrogel construct promoted bone osteogenesis by promoting cell proliferation, differentiation through activation of the PI3K/AKT signaling pathway.

Monitored deformation data during the construction of an urban subway.

The dataset is related to the ground surface and structure deformation during the construction of Chongqing subway line 9 in four months. The tunnel was constructed using drilling and blasting method as well as the tunnel boring machine (TBM). A systematic monitoring system was set in the site and it included monitoring points for ground subsidence, building settlement, vault deformation and the tunnel horizontal deformation. The deformation data in this article was measured using surveying in the site and it can be reused to validate numerical simulation results and guide the similar engineering project in the nearby area.

A neonatal mouse model of central nervous system infections caused by Coxsackievirus B5.

As one of the key members of the coxsackievirus B group, coxsackievirus B5 (CV-B5) can cause many central nervous system diseases, such as viral encephalitis, aseptic meningitis, and acute flaccid paralysis. Notably, epidemiological data indicate that outbreaks of CV-B5-associated central nervous system (CNS) diseases have been reported worldwide throughout history. In this study, which was conducted to promote CV-B5 vaccine and anti-virus drug research, a 3-day-old BALB/c mouse model was established using a CV-B5 clinical isolate (CV-B5/JS417) as the challenge strain. Mice challenged with CV-B5/JS417 exhibited a series of neural clinical symptoms and death with necrosis of neuronal cells in the cerebral cortex and the entire spinal cord, hindlimb muscles, and cardiomyocytes. The viral load of each tissue at various post-challenge time points suggested that CV-B5 replicated in the small intestine and was subsequently transmitted to various organs via viremia; the virus potentially entered the brain through the spinal axons, causing neuronal cell necrosis. In addition, this mouse model was used to evaluate the protective effect of a CV-B5 vaccine. The results indicated that both the inactivated CV-B5 vaccine and anti-CVB5 serum significantly protected mice from a lethal infection of CV-B5/JS417 by producing neutralizing antibodies. In summary, the first CV-B5 neonatal mouse model has been established and can sustain CNS infections in a manner similar to that observed in humans. This model will be a useful tool for studies on pathogenesis, vaccines, and anti-viral drug evaluations.

Seroepidemiology of coxsackievirus B5 in infants and children in Jiangsu province, China.

Coxsackievirus B5 (CV-B5) is associated with various human diseases such as viral encephalitis, aseptic meningitis, paralysis, herpangina, and hand, foot and mouth disease (HFMD). However, there is currently no effective vaccine against CV-B5.The seroepidemiologic characteristics of CV-B5 remained unknown. A cohort study was carried out in 176 participants aged 6-35 months from January 2012 to January 2014. The serum samples were collected and tested for CV-B5 neutralizing antibodies (NtAbs) four times during these two years. The confirmed enterovirus cases were recorded through the surveillance system, and their throat or rectal swabs were collected for pathogen detection. According to the changes of CV-B5 NtAbs, two CV-B5 epidemics were detected among these participants during the two-year follow-up. Sixty-seven cases out of all participants had seroconversion in CV-B5 NtAbs. During the first epidemic from March 2012 to September 2012, CV-B5 seropositivity rate increased significantly (6.8%, 12/176 vs. 21.6%, 38/176, P = 0.000). The seroconversion rate and geometric mean fold-increase (GMFI) were 18.2% (32/176) and 55.7, respectively; During the second epidemic from September 2012 to January 2014, CV-B5 seropositivity rate also increased (21.6%, 38/176 vs. 38.6%, 68/176, P = 0.000), and the seroconversion rate and GMFI were 19.9% (35/176) and 46.5, respectively. Only one case had CV-B5 associated HFMD during the two-year follow-up, and CV-B5 from the throat swab isolate was GI.D3 subtype, which belonged to the major pandemic strain in mainland China. CV-B5 infection was common in infants and children in Jiangsu province, China. Therefore, it's necessary to strengthen the surveillance on CV-B5 and to understand the epidemic characteristics of CV-B5 infection.

Development of a pseudovirus based assay for measuring neutralizing antibodies against coxsackievirus B5.

Coxsackievirus B5 (CV-B5), an important Coxsackie B virus from genus Enteroviruse within the family Picornaviridae, has also been isolated from Hand, Foot, and Mouth Disease (HFMD) patients, and often associated with neurological manifestations. In this study, we found out that Coxsackievirus B3 (CV-B3) replicon RNA could be encapsidated with CV-B5 capsid to assemble infectious CV-B5 pseudovirus. We then utilized this single round infection system of CV-B5 to develop a neutralizing antibody quantification assay. This pseudovirus neutralization assay showed superiority in biosafety, sensibility, quantitativity, efficiency and high throughput, and would facilitate the epidemiological studies and vaccine development of CV-B5.

Dynamics of 8G12 competitive antibody in "prime-boost" vaccination of Hepatitis E vaccine.

Hepatitis E virus still poses a great threat to public health worldwide. To date, Hecolin® is the only licensed HEV vaccine in China. Total anti-HEV antibody has been used to reflect vaccine induced immune response in clinical trials for the lack of robust HEV neutralizing antibody detection methods. In this study, we applied a broad neutralizing mouse monoclonal antibody 8G12 to develop a competitive ELSIA assay and quantified 8G12 competitive antibody (8G12-like antibody) in serum samples. The presence of 8G12-like antibody was detected both from participants from HEV vaccine clinical trial and mice immunized with HEV vaccine. Furthermore, 8G12-like antibody was found to have a similar dynamic pattern as anti-HEV antibody during "prime-boost" vaccination, and the proportion of 8G12-like antibody in anti-HEV antibody increased along boost vaccination. Together with previously reported finding that 8G12 could block the most binding of HEV vaccine induced serum antibody to vaccine antigen, we proposed that 8G12-like antibody might be a promising surrogate for vaccine induced HEV neutralizing antibody and had potential to be used as a convenient indicator for HEV vaccine potency evaluation.

Hepatitis E virus: Current epidemiology and vaccine.

Hepatitis E virus infections have been continuously reported in Indian subcontinent, Africa, southeast and central Asia, posing great health threats to the public, especially to pregnant women. Hecolin® is the only licensed HEV vaccine developed by Xiamen Innovax Biotech Co., Ltd. Extensive characterizations on antigenicity, physicochemical properties, efficacy in clinical trials, and manufacturing capability have made Hecolin® a promising vaccine for HEV control. However, there are many obstacles in large scale application of Hecolin®. Efforts are needed to further evaluate safety and efficacy in HEV risk populations, and to complement HEV standards for quality control. Passing World Health Organization prequalification and licensing outside China are priorities as these are also hindering Hecolin® promotion. Multilateral cooperation among Chinese vaccine manufacturers, Chinese National Regulatory Authorization (NRA) and WHO will expedite the entrance of Hecolin® into international market, so that Hecolin® could play its due role in global hepatitis E control.

A rapid and quantitative assay for measuring neutralizing antibodies of Coxsackievirus B3.

Coxsackievirus B3 (CVB3) infection has been found to account for an increasing proportion cases of hand, foot and mouth disease (HFMD) in recent epidemiology studies. CVB3 is a single stranded, non-enveloped RNA virus and the infection can cause prominent health threat to pre-school children. Here, by taking approaches of reverse genetics, we established a single-round infection system for CVB3. The pseudovirus was produced by sequential transfection of CVB3 capsid expresser plasmid and CVB3 replicon RNA bearing firefly luciferase as a reporter. The CVB3 pseudovirus system was used for quantifying neutralizing antibody (NtAb) levels of 720 human serum samples and showed superior specificity and sensitivity comparing traditional cytopathic effect (CPE) assay. Furthermore, we compared the seroprevalence of CVB3 NtAbs in pre-school children and healthy adults, and found that only 11.94% of pre-school children were NtAbs positive which suggested that most children were naive to CVB3 infection; while there is much higher positive rate in adults (60%) indicating that most adults have experienced CVB3 infection during childhood. This rapid and quantitative assay greatly facilitates evaluating the level of NtAbs against CVB3 in populations and will help to advance CVB3 vaccine development.