Global trends in the research and development of medical/pharmaceutical wastewater treatment over the half-century.

The COVID-19 pandemic has severely impacted public health and the worldwide economy. The overstretched operation of health systems around the world is accompanied by potential and ongoing environmental threats. At present, comprehensive scientific assessments of research on temporal changes in medical/pharmaceutical wastewater (MPWW), as well as estimations of researcher networks and scientific productivity are lacking. Therefore, we conducted a thorough literature study, using bibliometrics to reproduce research on medical wastewater over nearly half a century. Our primary goal is systematically to map the evolution of keyword clusters over time, and to obtain the structure and credibility of clusters. Our secondary objective was to measure research network performance (country, institution, and author) using CiteSpace and VOSviewer. We extracted 2306 papers published between 1981 and 2022. The co-cited reference network identified 16 clusters with well-structured networks (Q = 0.7716, S = 0.896). The main trends were as follows: 1) Early MPWW research prioritized sources of wastewater, and this cluster was considered to be the mainstream research frontier and direction, representing an important source and priority research area. 2) Mid-term research focused on characteristic contaminants and detection technologies. Particularly during 2000-2010, a period of rapid developments in global medical systems, pharmaceutical compounds (PhCs) in MPWW were recognized as a major threat to human health and the environment. 3) Recent research has focused on novel degradation technologies for PhC-containing MPWW, with high scores for research on biological methods. Wastewater-based epidemiology has emerged as being consistent with or predictive of the number of confirmed COVID-19 cases. Therefore, the application of MPWW in COVID-19 tracing will be of great interest to environmentalists. These results could guide the future direction of funding agencies and research groups.

MHC class I links with severe pathogenicity in C57BL/6N mice infected with SARS-CoV-2/BMA8.

BACKGROUND: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes non-symptomatic infection, mild influenza-like symptoms to pneumonia, severe acute respiratory distress syndrome, and even death, reflecting different clinical symptoms of viral infection. However, the mechanism of its pathogenicity remains unclear. Host-specific traits have a breakthrough significance for studying the pathogenicity of SARS-CoV-2. We previously reported SARS-CoV-2/BMA8, a mouse-adapted strain, was lethal to aged BALB/c mice but not to aged C57BL/6N mice. Here, we further investigate the differences in pathogenicity of BMA8 strain against wild-type aged C57BL/6N and BALB/c mice. METHODS: Whole blood and tissues were collected from mice before and after BMA8 strain infection. Viral replication and infectivity were assessed by detection of viral RNA copies and viral titers; the degree of inflammation in mice was tested by whole blood cell count, ELISA and RT-qPCR assays; the pathogenicity of SARS-CoV-2/BMA8 in mice was measured by Histopathology and Immunohistochemistry; and the immune level of mice was evaluated by flow cytometry to detect the number of CD8+ T cells. RESULTS: Our results suggest that SARS-CoV-2/BMA8 strain caused lower pathogenicity and inflammation level in C57BL/6N mice than in BALB/c mice. Interestingly, BALB/c mice whose MHC class I haplotype is H-2Kd showed more severe pathogenicity after infection with BMA8 strain, while blockade of H-2Kb in C57BL/6N mice was also able to cause this phenomenon. Furthermore, H-2Kb inhibition increased the expression of cytokines/chemokines and accelerated the decrease of CD8+ T cells caused by SARS-CoV-2/BMA8 infection. CONCLUSIONS: Taken together, our work shows that host MHC molecules play a crucial role in the pathogenicity differences of SARS-CoV-2/BMA8 infection. This provides a more profound insight into the pathogenesis of SARS-CoV-2, and contributes enlightenment and guidance for controlling the virus spread.

Super Dominant Pathobiontic Bacteria in the Nasopharyngeal Microbiota Cause Secondary Bacterial Infection in COVID-19 Patients.

Coronavirus disease 2019 (COVID-19) is a respiratory infectious disease responsible for many infections worldwide. Differences in respiratory microbiota may correlate with disease severity. Samples were collected from 20 severe and 51 mild COVID-19 patients. High-throughput sequencing of the 16S rRNA gene was used to analyze the bacterial community composition of the upper and lower respiratory tracts. The indices of diversity were analyzed. When one genus accounted for >50% of reads from a sample, it was defined as a super dominant pathobiontic bacterial genus (SDPG). In the upper respiratory tract, uniformity indices were significantly higher in the mild group than in the severe group (P < 0.001). In the lower respiratory tract, uniformity indices, richness indices, and the abundance-based coverage estimator were significantly higher in the mild group than in the severe group (P < 0.001). In patients with severe COVID-19, SDPGs were detected in 40.7% of upper and 63.2% of lower respiratory tract samples. In patients with mild COVID-19, only 10.8% of upper and 8.5% of lower respiratory tract samples yielded SDPGs. SDPGs were present in both upper and lower tracts in seven patients (35.0%), among which six (30.0%) patients possessed the same SDPG in the upper and lower tracts. However, no patients with mild infections had an SDPG in both tracts. Staphylococcus, Corynebacterium, and Acinetobacter were the main SDPGs. The number of SDPGs identified differed significantly between patients with mild and severe COVID-19 (P < 0.001). SDPGs in nasopharyngeal microbiota cause secondary bacterial infection in COVID-19 patients and aggravate pneumonia. IMPORTANCE The nasopharyngeal microbiota is composed of a variety of not only the true commensal bacterial species but also the two-face pathobionts, which are one a harmless commensal bacterial species and the other a highly invasive and deadly pathogen. In a previous study, we found that the diversity of nasopharyngeal microbiota was lost in severe influenza patients. We named the genus that accounted for over 50% of microbiota abundance as super dominant pathobiontic genus, which could invade to cause severe pneumonia, leading to high fatality. Similar phenomena were found here for SARS-CoV-2 infection. The diversity of nasopharyngeal microbiota was lost in severe COVID-19 infection patients. SDPGs in nasopharyngeal microbiota were frequently detected in severe COVID-19 patients. Therefore, the SDPGs in nasopharynx microbiota might invade into low respiratory and be responsible for secondary bacterial pneumonia in patients with SARS-CoV-2 infection.

Establishment of a rapid diagnosis assay for SARS-CoV-2 infection based on MALDI-TOF MS

Objective: To establish a rapid, high-throughput detection assay of serum peptidome profiling for the diagnosis of SARS-CoV-2 infection based on matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS).

Characterization of Two Heterogeneous Lethal Mouse-Adapted SARS-CoV-2 Variants Recapitulating Representative Aspects of Human COVID-19

New emerging severe acute respiratory syndrome 2 (SARS-CoV-2) has caused a worldwide pandemic. Several animal models of coronavirus disease 2019 (COVID-19) have been developed and applied to antiviral research. In this study, two lethal mouse-adapted SARS-CoV-2 variants (BMA8 and C57MA14) with different virulence were generated from different hosts, which are characterized by high viral replication titers in the upper and lower respiratory tract, pulmonary pathology, cytokine storm, cellular tropism, lymphopenia, and neutrophilia. Two variants exhibit host genetics-related and age-dependent morbidity and mortality in mice, exquisitely reflecting the clinical manifestation of asymptomatic, moderate, and severe COVID-19 patients. Notably, both variants equally weaken the neutralization capacity of the serum derived from COVID-19 convalescent, but the C57MA14 variant showed a much higher virulence than the BMA8 variant in vitro. Q489H substitution in the receptor-binding domain (RBD) of BMA8 and C57MA14 variants results in the receptors of SARS-CoV-2 switching from human angiotensin-converting enzyme 2 (hACE2) to murine angiotensin-converting enzyme 2 (mACE2). Additionally, A22D and A36V mutation in E protein were first reported in our study, which potentially contributed to the virulence difference between the two variants. Of note, the protective efficacy of the novel bacterium-like particle (BLP) vaccine candidate was validated using the BMA8- or C57MA14-infected aged mouse model. The BMA8 variant- and C57MA14 variant-infected models provide a relatively inexpensive and accessible evaluation platform for assessing the efficacy of vaccines and novel therapeutic approaches. This will promote further research in the transmissibility and pathogenicity mechanisms of SARS-CoV-2.

Incidence, Etiology, and Environmental Risk Factors of Community-Acquired Pneumonia Requiring Hospitalization in China: A 3-Year, Prospective, Age-Stratified, Multicenter Case-Control Study.

Background: Community-acquired pneumonia (CAP) is a leading infectious cause of hospitalization and death worldwide. Knowledge about the incidence and etiology of CAP in China is fragmented. Methods: A multicenter study performed at 4 hospitals in 4 regions in China and clinical samples from CAP patients were collected and used for pathogen identification from July 2016 to June 2019. Results: A total of 1674 patients were enrolled and the average annual incidence of hospitalized CAP was 18.7 (95% confidence interval, 18.5-19.0) cases per 10000 people. The most common viral and bacterial agents found in patients were respiratory syncytial virus (19.2%) and Streptococcus pneumoniae (9.3%). The coinfections percentage was 13.8%. Pathogen distribution displayed variations within age groups as well as seasonal and regional differences. The severe acute respiratory syndrome coronavirus 2 was not detected. Respiratory virus detection was significantly positively correlated with air pollutants (including particulate matter ≤2.5 µm, particulate matter ≤10 µm, nitrogen dioxide, and sulfur dioxide) and significantly negatively correlated with ambient temperature and ozone content; bacteria detection was opposite. Conclusions: The hospitalized CAP incidence in China was higher than previously known. CAP etiology showed that differences in age, seasons, regions, and respiratory viruses were detected at a higher rate than bacterial infection overall. Air pollutants and temperature have an influence on the detection of pathogens.

A Novel Strategy for the Detection of SARS-CoV-2 Variants Based on Multiplex PCR-Mass Spectrometry Minisequencing Technology.

The objective of this study was to construct a novel strategy for the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants using multiplex PCR-mass spectrometry minisequencing technique (mPCR-MS minisequencing). Using the nucleic acid sequence of a SARS-CoV-2 nonvariant and a synthetic SARS-CoV-2 variant-carrying plasmid, a matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) method based on the single-base mass probe extension of multiplex PCR amplification products was established to detect 9 mutation types in 7 mutated sites (HV6970del, N501Y, K417N, P681H, D614G, E484K, L452R, E484Q, and P681R) in the receptor-binding domain of the spike protein of SARS-CoV-2 variants. Twenty-one respiratory tract pathogens (9 bacteria and 12 respiratory viruses) and nucleic acid samples from non-COVID-19 patients were selected for specific validation. Twenty samples from COVID-19 patients were used to verify the accuracy of this method. The 9 mutation types could be detected simultaneously by triple PCR amplification coupled with MALDI-TOF MS. SARS-CoV-2 and six variants, B.1.1.7 (Alpha), B.1.351 (Beta), B.1.429 (Epsilon), B.1.526 (Iota), P.1 (Gamma) and B.1.617.2 (Delta), could be identified. The detection limit for all 9 sites was 1.5 × 103 copies. The specificity of this method was 100%, and the accuracy of real-time PCR cycle threshold (CT) values less than 27 among positive samples was 100%. This method is open and extensible, and can be used in a high-throughput manner, easily allowing the addition of new mutation sites as needed to identify and track new SARS-CoV-2 variants as they emerge. mPCR-MS minisequencing provides a new detection option with practical application value for SARS-CoV-2 and its variant infection. IMPORTANCE The emergence of SARS-CoV-2 variants is the key factor in the second wave of the COVID-19 pandemic. An all-in-one SARS-CoV-2 variant identification method based on a multiplex PCR-mass spectrometry minisequencing system was developed in this study. Six SARS-CoV-2 variants (Alpha, Beta, Epsilon, Iota, Gamma, and Delta) can be identified simultaneously. This method can not only achieve the multisite simultaneous detection that cannot be realized by PCR coupled with first-generation sequencing technology and quantitative PCR (qPCR) technology but also avoid the shortcomings of time-consuming, high-cost, and high technical requirements of whole-genome sequencing technology. As a simple screening assay for monitoring the emergence and spread of SARS-CoV-2 and variants, mPCR-MS minisequencing is expected to play an important role in the detection and monitoring of SARS-CoV-2 infection as a supplementary technology.

Wildlife-borne microorganisms and strategies to prevent and control emerging infectious diseases

China is one of the countries with the richest wildlife population. The large variety of widely distributed species act as natural or susceptible hosts for numerous infectious diseases. It is estimated that there are more than 1.2 million unknown virus species in China, and there might be 10,000–30,000 unknown bacteria in wild mammals on the Qinghai-Tibet Plateau alone. There are no less than 600,000 species of animal-borne parasites and approximately 2 million species of fungi worldwide. With rapid economic growth and globalization, humans and wildlife interact more frequently, which enhances the probability of wildlife-borne pathogens infecting humans. The occurrence of animal-borne infectious diseases will become the “new normal” we have to face in the future. Therefore, research should be carried out on wildlife-borne microorganisms and the prevention and control of emerging infectious diseases to establish an analytical framework and an evaluation technology system for risk assessment and early warning of potential animal-borne emerging infectious diseases. This will not only improve our understanding of wildlife-borne microbial communities but also enable in-depth analysis, discovery, early warning, and even prediction of major animal-borne emerging infectious diseases that might occur in the future. Furthermore, this research will reduce response times, minimize the social and economic impact and losses, enable interventions related to the emergence or spread of the disease as early as possible, and comprehensively improve our management of infectious disease outbreaks.

Progress in research in diagnosis of SARS-CoV-2 infection based on proteomics technique

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has swept the world in 2020, resulting in unprecedented pandemic of coronavirus disease 2019 (COVID-19). The number of infected persons and deaths increase every day at a frightening speed, threatening the health and life of people in the world and causing heavy burden to the global public health system. So far, nucleic acid detection is the main diagnostic method and gold standard for COVID-19. Meanwhile, other techniques and methods are also in developing for the diagnosis of SARS-CoV-2 infection. Proteomics technique is one of them. Proteomics technique has been widely used in the research of disease-related mechanism, development of diagnostic methods and pathogen identification. Up to now, there are mainly two applications of proteomics in the diagnosis of SARS-CoV-2 infection. First, proteomics based on virus particles has great potential in early diagnosis. Second, proteomics based on body fluids can be used not only for early diagnosis, but also for good monitoring the progress of infection, predicting the trend of disease, and evaluating the prognoses. In this paper, the research and application of proteomics technique in the diagnosis of SARS-CoV-2 infection in the world are summarized and prospected.

Predictive analysis and countermeasures in response to COVID-19 epidemic in 2020-2021

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a natural emerging virus, with rapid virus replication, wide cell tropism, and strong survival ability. Its epidemic characteristics are similar to those of influenza virus. Asymptomatic infections are widespread in a covert way, and the virus has adapted to human population, making it difficult to control the transmission. The global epidemic in 2020/2021 may further deteriorate before the SARS-CoV-2 vaccines are widely applied and show protective effectiveness, and China will still face the risk of continuous overseas multi-channel import and local outbreaks or recurrence of the epidemic. Therefore, it is necessary to carry out further surveillance about the prevalence and infection of SARS-CoV-2 in the population and the corresponding environment of the high-risk areas in China, and establish a national super mobile SARS-CoV-2 detection network laboratory for performing ultra-large-scale testing tasks;implement differentiated vaccination strategies and closely follow up and monitor the effectiveness and efficiency of vaccination;and continue to strengthen effective public health measures such as wearing masks, washing hands frequently, keeping social distances, opening windows frequently, and reducing gatherings. The coronavirus disease 2019 (COVID-19) epidemic warns us once again that the continuous emergence of new infectious diseases caused by unknown pathogens of wild animal origin has become the new normal status. It is necessary to systematically carry out unknown microbial discovery and reverse pathogenic etiology research in a prospective manner, and actively defend against emerging infectious diseases in the future.

Case Report: Identification of SARS-CoV-2 in Cerebrospinal Fluid by Ultrahigh-Depth Sequencing in a Patient With Coronavirus Disease 2019 and Neurological Dysfunction.

We reported that the complete genome sequence of SARS-Coronavirus-2 (SARS-CoV-2) was obtained from a cerebrospinal fluid (CSF) sample by ultrahigh-depth sequencing. Fourteen days after onset, seizures, maxillofacial convulsions, intractable hiccups and a significant increase in intracranial pressure developed in an adult coronavirus disease 2019 patient. The complete genome sequence of SARS-CoV-2 obtained from the cerebrospinal fluid indicates that SARS-CoV-2 can invade the central nervous system. In future, along with nervous system assessment, the pathogen genome detection and other indicators are needed for studying possible nervous system infection of SARS-CoV-2.

Network pharmacological analysis and mechanism prediction of Xingnaojing Injection in treatment of neurological damage caused by SARS-CoV-2

Objective: To explore the active compounds, targets and signaling pathways of Xingnaojing Injection (XNJI) for the treatment of neurological damage caused by SARS-CoV-2, so as to explore its mechanism. Methods: Using TCMSP, BATMAN, Swiss Target Prediction, and other databases, the chemical compounds and targets of XNJI were retrieved. Cytoscape software was used to construct XNJI efficacy network of "drug-compounds-targets" for coronavirus and neuroprotection, and the action mechanism was predicted by Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment. Then core compounds were verified by molecular docking with 3CL Mpro, ACE2, and 2019-nCoV RBD/ACE2-B0AT1 complex. Results: A total of 105 active compounds of XNJI, 928 drug targets, 741 targets of coronavirus, 611 targets of neuroprotection, 83 drug-disease common targets, 12 core compounds, and seven key targets were obtained. The function enrichment analysis of GO yielded 204 entries, KEGG pathway enrichment screened 120 signaling pathways, which included Hepatitis B, pathways in cancer, TNF, HIF-1, and VEGF signaling pathway, and so on. The results of molecular docking showed that core compounds of XNJI had a good bonding activity with 3CL Mpro, ACE2 and complex. The chlorogenin and kaempferol had the lowest binding energy with three proteins and might play an important role in treatment. Conclusion: The core compounds in XNJI including chlorogenin, kaempferol, 5-hydroxy- 6,7,3',4',5'-pentamethoxyflavone, 3-methylkempferol, morin, gardenin, quercetin, artemisetin, genistein, dryobalanone, curcumin, and elemicin, which might interfere with various signaling pathways by acting on key targets like PARP1, PTGS2, MMP9, CDK2, ADORA2A, ALOX5, GSK3B, and regulate the inflammatory response, apoptosis, oxidative stress, angiogenesis, and other processes to improve the neurological damage caused by SARS-CoV-2, and inhibit virus replication and prevent infection of the host cell by binding with 3CL Mpro, ACE2 and complex, which suggest that XNJI may have a positive therapeutic effect on the neurological damage caused by SARS-CoV-2.

Human monoclonal antibodies block the binding of SARS-CoV-2 spike protein to angiotensin converting enzyme 2 receptor (preprint)

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a global pandemic of novel corona virus disease (COVID-19). To date, no prophylactic vaccines or approved therapeutic agents are available for preventing and treating this highly transmittable disease. Here we report two monoclonal antibodies (mAbs) cloned from memory B cells of patients recently recovered from COVID-19, and both mAbs specifically bind to the spike (S) protein of SARS-CoV-2, block the binding of receptor binding domain (RBD) of SARS-CoV-2 to human angiotensin converting enzyme 2 (hACE2), and effectively neutralize S protein-pseudotyped virus infection. These human mAbs hold the promise for the prevention and treatment of the ongoing pandemic of COVID-19.