Gold-silver alloy hollow nanoshells-based lateral flow immunoassay for colorimetric, photothermal, and SERS tri-mode detection of SARS-CoV-2 neutralizing antibody.

Although many approaches have been developed for the quick assessment of SARS-CoV-2 infection, few of them are devoted to the detection of the neutralizing antibody, which is essential for assessing the effectiveness of vaccines. Herein, we developed a tri-mode lateral flow immunoassay (LFIA) platform based on gold-silver alloy hollow nanoshells (Au-Ag HNSs) for the sensitive and accurate quantification of neutralizing antibodies. By tuning the shell-to-core ratio, the surface plasmon resonance (SPR) absorption band of the Au-Ag HNSs is located within the near infrared (NIR) region, endowing them with an excellent photothermal effect under the irradiation of optical maser at 808 nm. Further, the Raman reporter molecule 4-mercaptobenzoic acid (MBA) was immobilized on the gold-silver alloy nanoshell to obtain an enhanced SERS signal. Thus, these Au-Ag HNSs could provide colorimetric, photothermal and SERS signals, with which, tri-mode strips for SARS-CoV-2 neutralizing antibody detection were constructed by competitive immunoassay. Since these three kinds of signals could complement one another, a more accurate detection was achieved. The tri-mode LFIA achieved a quantitative detection with detection limit of 20 ng/mL. Moreover, it also successfully detected the serum samples from 98 vaccinated volunteers with 79 positive results, exhibiting great application value in neutralizing antibody detection.

The impact of gingivitis reduction on lung function: a randomized trial under intensified oral hygiene.

BACKGROUND: Periodontal disease and lung function impairment were found to be associated with low-grade systemic or local inflammation, and it might be that gingival/periodontal inflammation triggers lung function due to systemic inflammation or the transfer of oral bacteria or its components to the lung. A recent observational study in non-smoking subjects showed that lung volumes and flow rates were significantly reduced by 71-185 ml for severe gingivitis regardless of the adjustment for potential confounders. The result did not show any confounding by smoking, and the association between gingivitis and lower lung function was not modified by systemic inflammation. The designed interventional trial primarily aims to test the hypothesis that gingivitis reduction by optimized daily oral hygiene, professional tooth cleaning and antibacterial chlorhexidine (CHX)-containing mouth rinse improves lung function in terms of forced vital capacity (FVC) by at least 2%. The secondary objective will test the hypothesis that gingivitis reduction improves forced expiratory volume in 1 s (FEV1) and forced expiratory flow at 25-75% of the pulmonary volume (FEF25-75) by at least 2%. Furthermore, the influence of the oral microbiome will be taken into account. METHODS: The study has to include 120 non-smoking subjects aged between 18 and 30 years with biofilm-induced gingivitis. The chosen "waiting control group design" will compare the immediate intervention group with the delayed intervention group, which serves as a control group. Dental and gingival status, lung function and oral microbiome will be recorded. The intensified preventive intervention-professional tooth cleaning, one-stage full-mouth disinfection with CHX and safeguarding an optimal daily oral hygiene by each subject-cannot be blinded, but the outcome measurement in terms of lung function tests is blind. DISCUSSION: This proposed multidisciplinary study has several strengths. Only one previous intervention study with patients with severe periodontitis (mostly smokers) has been performed. It is novel to include non-smoking subjects with mild and potentially reversible oral inflammation. Furthermore, this research is innovative, because it includes evidence-based interventions for gingivitis reduction, standardized measures of the outcome on lung function and oral microbiome and combines expertise from dentistry, lung physiology, oral microbiology and epidemiology/statistical modelling. TRIAL REGISTRATION: German Clinical Trial Register DRKS00028176. Registered on February 2022.

Colorimetric and Raman dual-mode lateral flow immunoassay detection of SARS-CoV-2 N protein antibody based on Ag nanoparticles with ultrathin Au shell assembled onto Fe3O4 nanoparticles.

Serological antibody tests are useful complements of nuclei acid detection for SARS-CoV-2 diagnosis, which can significantly improve diagnostic accuracy. However, antibody detection in serum or plasma remains challenging to do with high sensitivity. In this study, Ag nanoparticles with ultra-thin Au shells embedded with 4-mercaptobenzoic acid (MBA) (AgMBA@Au) were manufactured and then assembled onto Fe3O4 surface by electrostatic interaction to construct the Fe3O4-AgMBA@Au nanoparticles (NPs) with magnetic-Raman-colorimetric properties. Based on the composite nanoparticles, a colorimetric and Raman dual-mode lateral flow immunoassay (LFIA) for ultrasensitive identification of SARS-CoV-2 nucleocapsid (N) protein antibody was constructed. The magnetic nanoparticles (Fe3O4 NPs) were acted as the core and coated a layer of AgMBA@Au particles on the surface by electrostatic interaction to prepare Fe3O4-AgMBA@Au NPs, which can amplify the SERS signal due to multiple AgMBA@Au particles concentrated on a single magnetic nanoparticle. Moreover, the Fe3O4-AgMBA@Au NPs facilitated pre-purifying sample using magnetic separation, and complex matrix interference would be greatly decreased in the detection. The Fe3O4-AgMBA@Au NPs modified with N protein recognized and bound with N protein antibodies, which were trapped on the T-line, forming color band for observing detection. Under optimal conditions, the N protein antibodies could be qualitatively detected in colorimetric mode with the visual limit of 10-8 mg/mL and quantitatively detected by SERS signals between 10-6 and 10-10 mg /mL with 0.08 pg/mL detection limit. The coefficients variations (CV) of intra-assay was 8.0%, whereas of inter-assay was 11.7%, confirming of good reproducibility. Finally, this approach was able to discriminate between positive, negative, and weakly positive samples when detecting 107 clinical serum samples. The process enables highly sensitive quantitative assays that are valuable for evaluating disease processes and guiding treatment. Colorimetric and Raman dual-mode LFIA detection of SARS-CoV-2 N protein antibody based on Fe3O4-AgMBA@Au nanoparticles.

An achromatic colorimetric nanosensor for sensitive multiple pathogen detection by coupling plasmonic nanoparticles with magnetic separation.

Rapid screening of multiple pathogens will greatly improve the efficiency of pandemic prevention and control. Colorimetric methods exhibit the advantages of convenience, portability, low cost, time efficiency, and free of sophisticated instruments, yet usually have difficulties in simultaneous detection and suffer from monotonous color changes with low visual resolution and sensitivity. Hence, coupled three kinds of plasmonic nanoparticles (NPs) with magnetic separation, we developed an achromatic colorimetric nanosensor with highly enhanced visual resolution for simultaneous detection of SARS-CoV-2, Staphylococcus aureus, and Salmonella typhimurium. The achromatic nanosensor was composed of SARS-CoV-2-targeting red gold NPs, S. aureus-targeting yellow silver NPs and S. typhimurium-targeting blue silver triangle NPs mixed as black color. In the detection, three corresponding magnetic probes were added into the above mixture. In the presence of a target pathogen, it would be recognized and combined with corresponding colored reporters and magnetic probes to form sandwich complexes, which were removed by magnetic separation, and the sensor changed from black to a chromatic color (the color of the reporters remained in supernatant). Consequently, different target pathogen induced different color. For example, SARS-CoV-2, S. aureus, and S. typhimurium respectively produced green, purple, and orange. While coexistence of S. aureus and S. typhimurium produced red, and coexistence of S. aureus and SARS-CoV-2 produced blue, etc. Therefore, by observing the color change or measuring the absorption spectra, multiple pathogen detection was achieved conveniently. Compared with most colorimetric sensors, this achromatic nanosensor involved rich color change, thus significantly enhancing visual resolution and inspection sensitivity. Therefore, this sensor opened a promising avenue for efficient monitoring and early warning of food safety and quality.

When type II diabetes mellitus meets COVID-19-Identification of the shared gene signatures and biological mechanism between the two diseases.

BACKGROUND: According to current studies, more than 20% of all patients diagnosed with COVID-19 globally have diabetes. Further, the mortality rate of these patients is 7.3%. Compared with non-diabetic COVID-19 patients, diabetic COVID-19 patients have higher rates of mortality and severe infection, suggesting that diabetes is associated with the severity of COVID-19 infection. This study aimed to analyse the relationship and susceptibility factors between COVID-19 and T2DM. METHODS: Using bioinformatics methods, potential targets for COVID-19 and T2DM were screened from GeneCards database. Potential targets of COVID-19 and T2DM were mapped to each other to identify overlapping targets, and a PPI network was constructed to extract the core target. The clusterProfiler package in R was used to analyse the function and pathway that core target involved. GO enrichment and KEGG pathway analysis were used to elucidate the correlation between COVID-19 and T2DM. RESULTS: A total of 277 potential pathogenic targets of COVID-19 were found, 282 potential targets were found for T2DM. Mapping of the potential COVID-19 and T2DM targets revealed 53 overlapping targets, with TNF as the core target. IL-17 signalling pathway was the most significant KEGG pathway involving TNF. CONCLUSIONS: The inflammatory cytokine, TNF, was identified as a core target between COVID-19 and T2DM, which induces inflammatory response mainly through the IL-17 signalling pathway, leading to aggravation of infection and increased difficulty in blood glucose control. This study provides a reference for further exploring the potential correlation and endogenous mechanisms between two seemingly independent and unrelated diseases-T2DM and COVID-19.

When green enters a room: A scoping review of epidemiological studies on indoor plants and mental health.

BACKGROUND: Increasing numbers of epidemiological studies are investigating the association between outdoor greenery and various health outcomes. However, in the case of indoor plants, although experimental studies seem relatively abundant, epidemiological studies remain scarce, and research considering the mental health effects is even more limited. Thus, we aim to identify and summarise the relevant epidemiological studies on indoor plant exposure and mental health via this scoping review, thereby presenting the current state of knowledge and research niches. METHODS: PubMed and PsycINFO were systematically searched for epidemiological studies on indoor plant exposure and mental health, including mental and behavioural disorders, quality of life, and cognitive function. The publication period was from the inception of these two databases to 22nd June 2022. We extracted information on exposure to indoor plants and mental health-related outcomes from the relevant studies. RESULTS: The systematic search yielded 1186 unique results. Six studies met the inclusion criteria and were finally included in this scoping review. All included studies were Europe-based cross-sectional studies on mental and behavioural disorders. One study was conducted in 2015 and investigated the office environment, whereas the other five were conducted during the COVID-19 pandemic and focused on the home environment. Despite considerable heterogeneity in outcome assessments and indoor plant exposure metrics, all six studies generally reported beneficial associations between having indoor plants and mental health, such as reducing stress, depressive symptoms, and negative emotions. CONCLUSIONS: Epidemiological evidence on exposure to indoor plants and mental health is currently limited. In general, favourable effects of indoor plants are supported, although most relevant studies were conducted in the context of COVID-19. Before conducting more studies to explore the associations, data collection methods must be refined with more elaborate designs that allow for the measurement of more comprehensive metrics of indoor plants. REGISTRATION: Open Science Framework, osf.io/5xr6b.

An Intelligent Athlete Signal Processing Methodology for Balance Control Ability Assessment with Multi-Headed Self-Attention Mechanism

In different kinds of sports, the balance control ability plays an important role for every athlete. Therefore, coaches and athletes need accurate and efficient assessments of the balance control ability to improve the athletes’ training performance scientifically. With the fast growth of sport technology and training devices, intelligent and automatic assessment methods have been in high demand in the past years. This paper proposes a deep-learning-based method for a balance control ability assessment involving an analysis of the time-series signals from the athletes. The proposed method directly processes the raw data and provides the assessment results, with an end-to-end structure. This straight-forward structure facilitates its practical application. A deep learning model is employed to explore the target features with a multi-headed self-attention mechanism, which is a new approach to sports assessments. In the experiments, the real athletes’ balance control ability assessment data are utilized for the validation of the proposed method. Through comparisons with different existing methods, the accuracy rate of the proposed method is shown to be more than 95% for all four tasks, which is higher than the other compared methods for tasks containing more than one athlete of each level. The results show that the proposed method works effectively and efficiently in real scenarios for athlete balance control ability evaluations. However, reducing the proposed method’s calculation costs is an important task for future studies.

Ag Nanoparticles with Ultrathin Au Shell-Based Lateral Flow Immunoassay for Colorimetric and SERS Dual-Mode Detection of SARS-CoV-2 IgG.

Immunoglobulin detection is essential for diagnosing progression of SARS-CoV-2 infection, for which SARS-CoV-2 IgG is one of the most important indexes. In this paper, Ag nanoparticles with ultrathin Au shells (∼2 nm) embedded with 4-mercaptobenzoic acid (MBA) (AgMBA@Au) were manufactured via a ligand-assisted epitaxial growth method and integrated into lateral flow immunoassay (LFIA) for colorimetric and SERS dual-mode detection of SARS-CoV-2 IgG. AgMBA@Au possessed not only the surface chemistry advantages of Au but also the superior optical characteristics of Ag. Moreover, the nanogap between the Ag core and the Au shell also greatly enhanced the Raman signal. After being modified with anti-human antibodies, AgMBA@Au recognized and combined with SARS-CoV-2 IgG, which was captured by the SARS-CoV-2 spike protein on the T line. Qualitative analysis was achieved by visually observing the color of the T line, and quantitative analysis was conducted by measuring the SERS signal with a sensitivity four orders of magnitude higher (detection limit: 0.22 pg/mL). The intra-assay and inter-assay variation coefficients were 7.7 and 10.3%, respectively, and other proteins at concentrations of 10 to 20 times higher than those of SARS-CoV-2 IgG could hardly produce distinguishable signals, confirming good reproducibility and specificity. Finally, this method was used to detect 107 clinical serum samples. The results agreed well with those obtained from enzyme-linked immunosorbent assay kits and were significantly better than those of the colloidal gold test strips. Therefore, this dual-mode LFIA has great potential in clinical practical applications and can be used to screen and trace the early immune response of SARS-CoV-2.

[SARS-CoV-2 Infections during Travel by Train and Bus: A Systematic Review of Epidemiological Studies]. / SARS-CoV-2 Infektionen während Reisen mit Bahn und Bus. Ein systematisches Review epidemiologischer Studien.

AIM: The aim of this review is to identify epidemiological studies on the risk of infection with SARS-CoV-2 during travel by train and bus and to critically evaluate them also with regard to extrapolating the findings to the German situation. METHODS: Systematic review based on searching two electronic databases (PubMed, Web of Science) according to the principle of Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) for epidemiological studies on SARS-CoV-2 or COVID-19 and travel by train or bus. RESULTS: Searches of the two electronic databases yielded 746 publications. Of these, 55 met the selection criteria and were included in the full-text search. Finally, 5 original publications were used to answer the question about SARS-CoV-2 infections related to long-distance travel by train and 4 related to bus travel. The studies were very heterogeneous and referred almost exclusively to long-distance travel in China. They consistently showed a risk of infection when infected persons travelled in the same train, car or bus without mouth-to-nose (MNB) coverage. The risk was not limited to those sitting in close proximity to an infected fellow traveler. Despite all the differences between travel by train and bus in China and Germany, there is no fundamental doubt that the reported results from China can also be extrapolated to Germany in qualitative terms. However, it must be taken into account that the results of the three key publications predominantly included the period before the lockdown in China without the strict use of MNB. Thus, the question remains whether the results would be similar under current conditions with MNB and more virulent viral mutations. No single study was found related to infection when using public transportation. CONCLUSIONS: There are several lines of evidence that travel by train is associated with a significantly lower risk of infection compared with the risk of infection in the home environment. Due to a lack of observational data, one will need to model the risk of infection for long-distance travel by bus and use of local public transport based on air exchange in the passenger compartment, travel duration, distance from other passengers, and ultimately passenger density.