Multi-Scenario Validation and Assessment of a Particulate Matter Sensor Monitor Optimized by Machine Learning Methods.

OBJECTIVE: The aim was to evaluate and optimize the performance of sensor monitors in measuring PM2.5 and PM10 under typical emission scenarios both indoors and outdoors. METHOD: Parallel measurements and comparisons of PM2.5 and PM10 were carried out between sensor monitors and standard instruments in typical indoor (2 months) and outdoor environments (1 year) in Shanghai, respectively. The optimized validation model was determined by comparing six machining learning models, adjusting for meteorological and related factors. The intra- and inter-device variation, measurement accuracy, and stability of sensor monitors were calculated and compared before and after validation. RESULTS: Indoor particles were measured in a range of 0.8-370.7 µg/m3 and 1.9-465.2 µg/m3 for PM2.5 and PM10, respectively, while the outdoor ones were in the ranges of 1.0-211.0 µg/m3 and 0.0-493.0 µg/m3, correspondingly. Compared to machine learning models including multivariate linear model (ML), K-nearest neighbor model (KNN), support vector machine model (SVM), decision tree model (DT), and neural network model (MLP), the random forest (RF) model showed the best validation after adjusting for temperature, relative humidity (RH), PM2.5/PM10 ratios, and measurement time lengths (months) for both PM2.5 and PM10, in indoor (R2: 0.97 and 0.91, root-mean-square error (RMSE) of 1.91 µg/m3 and 4.56 µg/m3, respectively) and outdoor environments (R2: 0.90 and 0.80, RMSE of 5.61 µg/m3 and 17.54 µg/m3, respectively), respectively. CONCLUSIONS: Sensor monitors could provide reliable measurements of PM2.5 and PM10 with high accuracy and acceptable inter and intra-device consistency under typical indoor and outdoor scenarios after validation by RF model. Adjusting for both climate factors and the ratio of PM2.5/PM10 could improve the validation performance.

The impact of preoperative biliary drainage on postoperative healthcare-associated infections and clinical outcomes following pancreaticoduodenectomy: a ten-year retrospective analysis.

BACKGROUND: Pancreaticoduodenectomy (PD) is a complex procedure and easily accompanied by healthcare-associated infections (HAIs). This study aimed to assess the impact of PBD on postoperative infections and clinical outcomes in PD patients. METHODS: The retrospective cohort study were conducted in a tertiary hospital from January 2013 to December 2022. Clinical and epidemiological data were collected from HAIs surveillance system and analyzed. RESULTS: Among 2842 patients who underwent PD, 247 (8.7%) were diagnosed with HAIs, with surgical site infection being the most frequent type (n = 177, 71.7%). A total of 369 pathogenic strains were detected, with Klebsiella pneumoniae having the highest proportion, followed by Enterococcu and Escherichia coli. Although no significant association were observed generally between PBD and postoperative HAIs, subgroup analysis revealed that PBD was associated with postoperative HAIs in patients undergoing robotic PD (aRR = 2.174; 95% CI:1.011-4.674; P = 0.047). Prolonging the interval between PBD and PD could reduce postoperative HAIs in patients with cholangiocarcinoma (≥4 week: aRR = 0.292, 95% CI 0.100-0.853; P = 0.024) and robotic PD (≤2 week: aRR = 3.058, 95% CI 1.178-7.940; P = 0.022). PBD was also found to increase transfer of patients to ICU (aRR = 1.351; 95% CI 1.119-1.632; P = 0.002), extended length of stay (P < 0.001) and postoperative length of stay (P = 0.004). CONCLUSION: PBD does not exhibit a significant association with postoperative HAIs or other outcomes. However, the implementation of robotic PD, along with a suitable extension of the interval between PBD and PD, appear to confer advantages concerning patients' physiological recuperation. These observations suggest potential strategies that may contribute to enhanced patient outcomes.

Epidemiology of healthcare-associated infections and outcomes among open and robotic pancreatoduodenectomy: A retrospective study from 2013 to 2022.

BACKGROUND AND AIM: Healthcare-associated infections (HAIs) after pancreaticoduodenectomy (PD) are one of the common postoperative complications. This study aims to investigate the epidemiology of postoperative HAIs in patients with open pancreaticoduodenectomy (OPD) and robotic pancreaticoduodenectomy (RPD). METHODS: This retrospective cohort study described the trend of HAIs in patients undergoing PD from January 2013 to December 2022 at a tertiary hospital. Patients were divided into OPD and RPD, and the HAIs and outcomes were compared. RESULTS: Among 2632 patients who underwent PD, 230 (8.7%, 95% confidence interval [CI] 7.7-9.9%) were diagnosed with HAIs, with a decreasing trend from 2013 to 2022 (P < 0.001 for trend). The incidence of postoperative HAIs was significantly higher in patients with OPD than RPD (9.6% vs 5.8%; P = 0.003). The incidence of HAIs for patients with OPD showed a decreasing trend (P = 0.001 for trend), and the trend for RPD was not significant (P = 0.554 for trend). Logistic regression showed that RPD was significantly associated with postoperative HAIs after adjusting for covariates (adjusted odds ratio = 0.654; 95% CI 0.443-0.965; P = 0.032), especially in the subgroup of patients without preoperative biliary drainage (adjusted odds ratio = 0.486; 95% CI 0.292-0.809; P = 0.006). Regarding clinical outcomes, RPD has a shorter length of stay and a more expensive charge than OPD (all P < 0.05). CONCLUSION: Postoperative HAIs in patients with PD showed a decreasing trend in recent years, especially in OPD. RPD was significantly associated with reduced postoperative HAIs and length of stay, although the charge is more expensive. Attention should be paid to postoperative HAIs in OPD, and it is imperative to continue reducing the costs of RPD.

Differences in Pathogenicity and Vaccine Resistance Discovered between Two Epidemic Strains of Marek's Disease Virus in China.

Despite highly effective vaccines, Marek's disease (MD) causes great economic loss to the poultry industry annually, largely due to the continuous emergence of new MD virus (MDV) strains. To explore the pathogenic characteristics of newly emerged MDV strains, we selected two strains (AH/1807 and DH/18) with clinically different pathotypes. We studied each strain's infection process and pathogenicity and observed differences in immunosuppression and vaccine resistance. Specific pathogen-free chickens, unvaccinated or vaccinated with CVI988, were challenged with AH/1807 or DH/18. Both infections induced MD damage; however, differences were observed in terms of mortality (AH/1807: 77.8%, DH/18: 50%) and tumor rates (AH/1807: 50%, DH/18: 33.3%). The immune protection indices of the vaccine also differed (AH/1807: 94.1, DH/18: 61.1). Additionally, while both strains caused interferon-ß and interferon-γ expression to decline, DH/18 infection caused stronger immunosuppression than AH/1807. This inhibition persisted even after vaccination, leading to increased replication of DH/18 that ultimately broke through vaccine immune protection. These results indicate that both strains have different characteristics, and that strains such as DH/18, which cause weaker pathogenic damage but can break through vaccine immune protection, require further attention. Our findings increase the understanding of the differences between epidemic strains and factors underlying MD vaccination failure in China.

Efficient CRISPR-Cas13d-Based Antiviral Strategy to Combat SARS-CoV-2.

The current SARS-CoV-2 pandemic forms a major global health burden. Although protective vaccines are available, concerns remain as new virus variants continue to appear. CRISPR-based gene-editing approaches offer an attractive therapeutic strategy as the CRISPR-RNA (crRNA) can be adjusted rapidly to accommodate a new viral genome sequence. This study aimed at using the RNA-targeting CRISPR-Cas13d system to attack highly conserved sequences in the viral RNA genome, thereby preparing for future zoonotic outbreaks of other coronaviruses. We designed 29 crRNAs targeting highly conserved sequences along the complete SARS-CoV-2 genome. Several crRNAs demonstrated efficient silencing of a reporter with the matching viral target sequence and efficient inhibition of a SARS-CoV-2 replicon. The crRNAs that suppress SARS-CoV-2 were also able to suppress SARS-CoV, thus demonstrating the breadth of this antiviral strategy. Strikingly, we observed that only crRNAs directed against the plus-genomic RNA demonstrated antiviral activity in the replicon assay, in contrast to those that bind the minus-genomic RNA, the replication intermediate. These results point to a major difference in the vulnerability and biology of the +RNA versus -RNA strands of the SARS-CoV-2 genome and provide important insights for the design of RNA-targeting antivirals.

Complete genome analysis reveals evolutionary history and temporal dynamics of Marek's disease virus.

Marek's disease has caused enormous losses in poultry production worldwide. However, the evolutionary process and molecular mechanisms underlying Marek's disease virus (MDV) remain largely unknown. Using complete genomic sequences spanning an unprecedented diversity of MDVs, we explored the evolutionary history and major patterns in viruses sampled from 1964 to 2018. We found that the evolution of MDV strains had obvious geographical features, with the Eurasian and North American strains having independent evolutionary paths, especially for Asian strains. The evolution of MDVs generally followed a clock-like structure with a relatively high evolutionary rate. Asian strains had evolved at a faster rate than European strains, with most genetic mutations occurring in Asian strains. Our results showed that all recombination events occurred in the UL and US subregions. We found direct evidence of a closer correlation between Eurasian strains, related to a series of reorganization events represented by the European strain ATE2539. We also discovered that the vaccine strains had recombined with the wild virulent strains. Base substitution and recombination were found to be the two main mechanisms of MDV evolution. Our study offers novel insights into the evolution of MDVs that could facilitate predicting the spread of infections, and hence their control.

Emerging natural recombinant Marek's disease virus between vaccine and virulence strains and their pathogenicity.

Marek's disease virus (MDV), an oncogenic virus belonging to the subfamily Alphaherpesvirinae, causes Marek's disease (MD). Vaccines can control MD but cannot block the viral infection; they are considered imperfect vaccines, which carry the risk of recombination. In this study, six natural recombinant MDV strains were isolated from infected chickens in commercial flocks in China. We sequenced and analysed the genetic characteristics of the isolates (HC/0803, CH/10, SY/1219, DH/1307, DH/1504 and Hrb/1504). We found that the six strains resulted from recombination between the vaccine CVI988/Rispens (CVI988) strain skeleton and the virulence strain's partial unique short region. Additionally, a pathogenicity study was performed on recombinant strains (HC/0803 and DH/1307) and reference strains (CVI988 and LHC2) to evaluate their virulence. LHC2 induced 84.6% mortality in infected chickens; however, no mortality was recorded in chickens inoculated with HC/0803, DH/1307 or CVI988. However, HC/0803 and DH/1307 induced a notable spleen enlargement, and mild thymus and bursa atrophy at 11-17 days post-challenge (dpc). The viral genome load in the HC/0803- and DH/1307-challenged chickens peaked at approximately 107 viral copies per million host cells at 17 dpc and was similar to that in LHC2-challenged chickens, but significantly higher than that of CVI988-challenged chickens. In summary, HC/0803 and DH/1307 displayed mild virulence with temporal damage to the immune organs of chicken and a higher reproduction capability than the vaccine strain CVI988. Our study provides direct evidence of the emergence of recombinant MDV strains between vaccine and virulence strains in nature. The emergence of natural recombinant strains suggests that live vaccines can act as genetic donors for genomic recombination, and recombination may be a safety concern when administering live vaccines. These findings demonstrate that recombination promotes genetic diversity and increases the complexity of disease diagnosis, prevention and control.

The Psychological Effect of Forming WeChat Groups Between Medical Staff and Patients With COVID-19.

Background: This study was conducted in order to explore the effect of psychological intervention based on the use of WeChat with coronavirus disease 2019 (COVID-19) patients. Methods: A total of 65 patients with COVID-19, from two wards, were divided into an experimental group and a control group with the ward as the basic unit. Communication concerning routine treatment and nursing was established between the medical staff and patients in the experimental group via WeChat groups. Within 48 h of admission, at 7 days, and on discharge, all 65 patients completed two self-evaluation questionnaires: the Positive and Negative Affect Schedule (PANAS) and the Hospital Anxiety and Depression Scale (HADS). Hospital stay statistics and a satisfaction survey on discharge were also collated for both groups of patients. Results: The PANAS scores of the experimental group were 26.61 ± 7.99 points on admission, 20.81 ± 5.48 points at 7 days, and 19.58 ± 6.61 points on discharge (P < 0.05). The scores of HADS in the experimental group were 27.74 ± 9.35 points on admission, 12.19 ± 1.92 points at 7 days, and 11.71 ± 3.64 points on discharge (P < 0.05). The differences in the PANS and HADS scores between the experimental and control groups at 7 days and on discharge were statistically significant. The discharge satisfaction ratings of the two groups of patients were 99.87 ± 0.34 and 98.68 ± 1.09 points, the difference being statistically significant (t = 5.827, P < 0.05). Conclusion: Establishing WeChat groups between medical staff and patients with COVID-19 and building a bridge for better communication improved patients' positive mentality and their compliance with doctors, shortened their hospital stay, and promoted their recovery.

Chemodynamic Therapy Combined with Multifunctional Nanomaterials and Their Applications in Tumor Treatment.

During the past few decades, radiotherapy and chemotherapy have been the standard approaches for tumor treatments. However, the potential toxic effect and side effects of both radiotherapy and chemotherapy on the human body still cannot be neglected. Given this, the Fenton reaction has become one of the most effective treatment strategies to combat tumor cells. This review aims to summarize the recent advances comprehensively and systematically in chemodynamic therapy (CDT) via the Fenton reaction. In addition, a host of the advanced nano-multifunctional materials and engineering bacteria used in the Fenton reaction were also summarized. This paper would be helpful to provide guidance and lay firm foundations for future tumor treatment.

Natural co-infection with two virulent wild strains of Marek's disease virus in a commercial layer flock.

Marek's disease (MD) is a highly contagious lymphoproliferative poultry disease caused by the oncogenic herpesvirus, Marek's disease virus (MDV). MDV strains have shown a continued evolution of virulence leading to immune failure, and MD cases continue to occur. Co-infection of virulent MDV strains is an important factor leading to viral evolution and host immune failure. This study conducted a laboratory diagnosis and analysis of a MDV infected flock. Testing showed that all samples were MDV positive. PCR detection identified a variable 132-base pair repeat (132-bpr) sequence copy number. This indicated that two virulent strains of MDV were co-infecting the flock. Therefore, we performed homology, sequence alignment, and phylogenetic tree analysis of MDV variant genes including meq, pp38, and RLORF4. Two MDV strains had co-infected the flock; one was the 132bpr two-copy characteristic strain (AH2C) and the other was a 132bpr three-copy characteristic strain (AH3C). Specific mutations in AH3C were found, suggesting that it is a new variant strain. Furthermore, the viral load of the two strains in vivo indicated that both strains had high and similar replication ability. There was no significant difference in the proportion of positive samples of the two strains causing disease. In the whole flock, neither strain displayed an obvious advantage. However, there was a dominant strain in individual chickens, with the exception of one sample. This study reported the co-infection regularity of two virulent MDV strains in the same flock, and even in the same chicken in field conditions. In the context of overall epidemiology, this study is a useful reference.

A high frequency of Gallid herpesvirus-2 co-infection with Reticuloendotheliosis virusis associated with high tumor rates in Chinese chicken farms.

The prevalence of Marek's disease (MD) caused by Gallid herpesvirus-2 (GaHV-2) has been increasing in chickens in China despite universal vaccination. Among the possible reasons for this trend, of Reticuloendotheliosis virus (REV) contamination in vaccines could lead to co-infection and reduce the vaccine efficacy. Here, we report the epidemiological findings of our continuous surveillance of MD, and an examination of the effects of REV and/or GaHV-2 co-infection. A total of 1230 samples were collected between 2011 and 2015 from 305 flocks covering many of the chicken-raising regions of China. Among these, 606 samples were determined to be GaHV-2-positive, 13.0% of which were found to be co-infected with REV from 18.8% of the flocks. One GaHV-2 strain (HS/1412), a REV strain (HS/1412R), and a GaHV-2 and REV-co-infected strain (HS/1412 GR) were isolated from different chickens of a GaHV-2 and REV co-infected flock. Pathogenicity tests showed that HS/1412 and HS/1412 GR caused disease in all chickens and that HS/1412R induced morbidity in 84.6% of the infected chickens. HS/1412 GR induced 100% mortality and 76.9% tumor formation, which were significantly higher frequencies than those observed with strain HS/1412 (38.5% and 15.4%, respectively) and HS/1412R (0% and 0%). These results indicate that co-infection with GaHV-2 and REV might explain the persistent, sporadic outbreaks of neoplastic disease in some commercial flocks, resulting in a significant economic burden to the poultry industry of China.

Differential expression of type I interferon mRNA and protein levels induced by virulent Marek's disease virus infection in chickens.

Marek's disease virus (MDV), an α-herpesvirus targeting avian species, causes fatal Marek's disease (MD) in chickens. The host interferon (IFN) responses play a key role in resisting viral infection. However, host IFN responses following MDV infection in the chicken central immune organs (thymus and bursa of Fabricius), which contain numerous MDV target cells, is poorly understood. In this study, we performed animal experiments in specific pathogen-free chickens infected with two virulent MDV strains (BS/15 and Md5) or without infection as negative controls. Specifically, the type I IFN (IFN-α and IFN-ß) transcriptional and proteomic expression levels at 7, 10, 14, 17, and 21 days post infection (dpi) were detected and analyzed. Our results indicated that the mRNA and protein expression levels of IFN-α and IFN-ß in the thymus and bursa of Fabricius were mainly downregulated in cytolytic infection (such as 10 dpi) and reactivation (such as 17 dpi) stages, but not the latent (such as 14 dpi) stage of MDV infection, which was determined by comprehensively analyzing the MDV viral load and immune organ damage caused by MDV infection. These data suggest that MDV could inhibit the expression of host type I IFNs, which may be involved in the MDV-induced host immunosuppression and contribute to the immune escape of MDV from host immunity. Furthermore, we found that the downregulated expression of the host type I IFNs induced by BS/15 and Md5 infection was significantly different, which we speculated may be related to the diverse virulence and pathogenicity of MDV strains. In conclusion, our study demonstrated that MDV mostly inhibited the expression of type I IFNs in infected hosts, which may be associated to its pathogenesis.