Wastewater-based surveillance has been put into practice during the pandemic. Persistence of SARS-CoV-2 in faeces of infected individuals, and high volume of passengers travelling by air, make it possible to detect virus from aircraft wastewater, lending itself to the potential identification of a novel pathogen prior to clinical diagnosis. In this study, we estimated the likelihood of detecting the virus through aircraft wastewater from the probabilities of air travel, viral shedding, defecation, testing sensitivity, and sampling. We considered various hypothetical scenarios, with diverse sampling proportions of inbound flights, surveillance airports, and sources of outbreaks. Our calculations showed that the probability of detecting SARS-CoV-2 would increase exponentially against time in the early phase of the pandemic, and would be much higher if the 20 major airports in Asia, Europe, and North America cooperated to perform aircraft wastewater surveillance. We also found other contributors to early detection, including high sampling proportion of inbound flight at destination airports, small population size of the epicentre relative to the travel volume, and large volume of outbound travelers to major airports around the globe. We concluded that routine aircraft wastewater monitoring could be a feasible approach for early identification and tracking of an emerging pathogen with high faecal shedding rates, particularly when implemented through a global surveillance network of major airports.
BACKGROUND:Age-related gut microbial changes have been widely investigated over the past decade. Most of the previous age-related microbiome studies were conducted on the Western population, and the short-read sequencing (e.g., 16S V4 or V3-V4 region) was the most common microbiota profiling method. We evaluated the gut compositional differences using the long-read sequencing approach (i.e., PacBio sequencing targeting the full-length V1-V9 regions) to enable a deeper taxonomic resolution and better characterize the gut microbiome of Singaporeans from different age groups. RESULTS:A total of 83 research participants were included in this study. Although no significant differences were detected in alpha and beta diversity, our study demonstrated several bacterial taxa with abundances that were significantly different across age groups. With young individuals as the reference group, Eggerthella lenta and Bacteroides uniformis were found to be significantly altered in the middle-aged group, while Catenibacterium mitsuokai and Bacteroides plebeius were significantly altered in the elderly group. These age-related differences in the gut microbiome were associated with aberrations in several predicted functional pathways, including dysregulations of pathways related to lipopolysaccharide and tricarboxylic acid cycle in older adults. CONCLUSIONS:The utilization of long-read sequencing facilitated the identification of species- and strain-level differences across age groups, which was challenging with the partial 16S rRNA sequencing approach. Nevertheless, replication studies are warranted to confirm our findings, and if confirmed, further in vitro and in vivo studies are crucial to better understand the impact of the altered levels of age-related bacterial taxa. Additionally, the modest performance of strain-level taxonomic classification using 16S-ITS-23S gene sequences, likely due to the limited depth of currently available alignment databases, highlights the need for optimization and refinement in curating these databases for the long-read sequencing approach.
Kombucha is a fermented tea traditionally known for its health-enhancing properties owing to the bioactive compounds generated by acetic acid bacteria (AAB) and lactic acid bacteria (LAB). We compared the distribution of AAB and LAB and their functional pathways across nine commercial kombucha products in Singapore using shotgun metagenomic sequencing. A high prevalence of Komagataeibacter species including Komagataeibacter saccharivorans (82.93% in B), Komagataeibacter xylinus (93.38% in D) and Komagataeibacter rhaeticus (92.20% and 30.62% in G and I) was detected in AAB-dominant kombucha. LAB-dominant kombucha was largely represented by Bacillus coagulans (~99% in E and F) and Lactobacillus nagelii (~60% in H). Despite differences in bacterial composition, both LAB-and AAB-dominant kombucha harbour pathways involved in the biosynthesis of short-chain fatty acids (SCFAs), amino and organic acids and vitamin B12. “Fatty acid and beta-oxidation II (peroxisome)” and “fatty acid and beta-oxidation I” were detected in the LAB but not the AAB-dominant kombucha.
Microbiome is associated with a wide range of diseases. The gut microbiome is also a dynamic reflection of health status, which can be modified, thus representing great potential to exploit the mechanisms that influence human physiology. Recent years have seen a dramatic rise in gut microbiome studies, which has been enabled by the rapidly evolving high-throughput sequencing methods (i.e. 16S rRNA sequencing and shotgun sequencing). As the emerging technologies for microbiome research continue to evolve (i.e. metatranscriptomics, metabolomics, culturomics, synthetic biology), microbiome research has moved beyond phylogenetic descriptions and towards mechanistic analyses. In this review, we highlight different approaches to study the microbiome, in particular, the current limitations and future promise of these techniques. This review aims to provide clinicians with a framework for studying the microbiome, as well as to accelerate the adoption of these techniques in clinical practice.
Background Recent studies demonstrate the association of the gut microbiome in regulating interactions between the central nervous system and intestinal function. Individuals with attention-deficit hyperactivity disorder (ADHD) have been shown to have unique gut microbial signature, with depletion of beneficial commensal microbes. Fecal microbiota transplant (FMT) restores the imbalanced gut microbiome and may replete missing microbes to increase production of hormones and neurotransmitters regulating human behavior and cognition.Research design & methods Here, we present an interesting case of a 22-year-old woman treated with FMT primarily to treat recurrent Clostridioides difficile infection, which coincidentally alleviated her ADHD symptoms. We also present the pre- and post-FMT gut microbiota profiles conducted using shotgun metagenomic sequencing on the patient's fecal samples to thereby highlight potential microbial-associated mechanisms associated with the relief of ADHD symptoms.Results & conclusions Our case report provides preliminary evidence regarding the use of FMT in a patient with C. difficile and ADHD. We speculate that gut microbiome modulation, in particular the gain or loss of specific microbial species and pathways involving the metabolism of SCFAs, tryptophan and GABA, may merit further exploration as a potential therapeutic strategy for ADHD.
Background Atrial fibrillation (AF) is the most common arrythmia and is associated with costly morbidity such as stroke and heart failure. Mobile health (mHealth) has potential to help bridge the gaps of traditional healthcare models that may be poorly suited to the sporadic nature of AF. The Self-management and Educational technology support Tool for AF patients (SETAF) was designed based on the preferences and needs of AF patients but more study is required to assess the acceptance of this novel tool. Objective Explore the usability and acceptance of SETAF among AF patients in Singapore. Methods A mixed methods study was conducted with AF patients who were purposively sampled from an outpatient cardiology clinic in Singapore. After 6 weeks of using SETAF, semi-structured interviews were performed, and data were analyzed inductively following a thematic analysis approach. Results from a short 4-item survey and application usage data were also analyzed descriptively. Both qualitative and quantitative results were organized and presented following the Technology Acceptance Model (TAM) framework. Results A total of 37 patients participated in the study and 19 were interviewed. Participants perceived SETAF as useful for improving AF knowledge, self-management and access to healthcare providers and was easy to use due to the guided tutorial and user-friendly interface. They also identified the need for better personalization of content, psychosocial support features and reduction of language barriers. Application usage data revealed preference for AF related content and decreased interaction with the motivational message component of SETAF over time. Overall, most of the participants would continue using SETAF and were willing to pay for it. Conclusions AF patients in Singapore found SETAF useful and acceptable as a tool for AF management. The insights from this study not only support the potential of mHealth but may also inform the design and implementation of future mHealth tools for AF patients.
(TCAs), exhibit antibacterial activities. Hence, this systematic review explores the impact of antidepressants on gut microbiota and potential strategies to alleviate antidepressant-associated dysbiosis. Methods This systematic review was conducted based on the PRISMA guidelines. Predefined MeSH terms ‘antidepressants AND gut microbiome’; ‘antidepressants AND antimicrobial activity’ were used in three databases (Pubmed, Embase, ProQuest; from database inception to June 2021). Studies reporting on the gut microbiota variation and antidepressants action were included. Studies without antidepressants and/or gut microbiome data were excluded, including conference proceedings, reviews, systematic reviews, meta-analyses, and commentaries. Results According to the study’s inclusion criteria, twelve studies out of 300 articles were selected for the qualitative analysis. In the in-vivo studies, animals administrated with SSRIs had a decreased abundance of Firmicutes, Alphaproteobacteria, Bacteroides, Ruminococcus, Adlercreutzia, Turicibacter, and alpha diversity but an increase in Prevotella, Parabacteroides, Butyricimonas, and Alistipes. Besides, antidepressants were shown to exhibit significant in vitro antimicrobial activity against Akkermansia muciniphila, Bifidobacterium animalis, and Bacteroides fragilis, suggesting that the chronic use of antidepressants potentially causes adverse effects due to their antimicrobial effects and dysbiosis (IDDF2021-ABS-0164 Figure 1. Illustration of gut microbiota dysbiosis in response to antidepressants). Probiotics, prebiotics and fecal microbiota transplantation are shown to be promising strategies to ameliorate antidepressant-associated dysbiosis. Conclusions Understanding the interaction between antidepressants and gut microbiota, including dysbiosis as a consequence of treatment and potential side effects, is vital for the future development of better and personalized treatment. Supplementing the gut microbiome with prebiotics/probiotics could be an adjuvant treatment to improve the clinical efficacy of the current antidepressant therapies. IDDF2021-ABS-0165 PSYCHOLOGICAL WELL-BEING AND SLEEP QUALITY AMONG HEALTHY STOOL DONORS IN SINGAPORE: A CROSSSECTIONAL STUDY
Background: Recent scientific developments have suggested Fecal Microbiota Transplantation (FMT) as a promising treatment modality for diseases as diverse as Inflammatory Bowel Disease and autism. Recent studies have also highlighted the importance of the gut microbiome (GM) in many common diseases such as diabetes. Nonetheless, the level of public knowledge and perceptions of the GM and FMT remain unclear. This study aims to identify the degrees of knowledge, awareness and perception in Singaporean adults regarding human GM and FMT, which would allow the implementation of education programmes that effectively inform target groups. Methods: A 19-question online survey was administered to 1,831 Singaporean adults from the Singapore Population Health Studies Online Panel, a population-based cohort consisting of Chinese, Malay and Indian participants. The questionnaire provided information about FMT and GM, and surveyed participants’ knowledge and perceptions of both topics. Results: Only 32.6% of participants have ever heard of GM before. However, 92.7% have consumed probiotic drinks, of which almost half consumed for gut health. Nearly 84.8% have not heard of FMT before, but 72.0% would consider undergoing FMT to treat CDI. Approximately 58.1% chose colonoscopy over the nasal passage as the preferred mode of FMT. Preference for oral medication (57.2%) and being uncomfortable with the concept of FMT (54.1%) were the main reasons behind refusing FMT. About 52.1% were much more inclined to accept FMT if orally administered in capsule-form. Willingness to receive FMT depended on recommendation from healthcare providers (77.1%) and clinical studies (59.7%). Conclusions: Awareness regarding GM and FMT were relatively low despite high engagement amongst participants in behaviours that improve gut health. Strategies to raise awareness may focus on the benefits of GM to cater to an increasingly health-conscious society. Barriers to accepting FMT may be overcome by making validated sources of information readily available for the public.
Background The gut microbiome plays an instrumental role in cardiovascular, metabolic and gastrointestinal health (Valdes et al. 2018). In Traditional Chinese Medicine (TCM), one’s health status can be described by nine body constitutions (BCs) which are broadly classified as ‘Neutral’, indicating optimal health, or ‘Unbalanced’, indicating suboptimal health. Similar to the gut microbiome, BCs are strongly influenced by lifestyle and diet. We evaluated the gut microbial composition of Neutral, Qi-Deficiency (QD), Phlegm-dampness (PD) and Damp Heat (DH) subjects. The latter three are unbalanced BCs, with QD associated with heart disease (Zhu et al. 2017), PD with obesity and metabolic syndrome (Wang et al. 2013), and DH with gastrointestinal disease (Liang et al. 2020). Methods Stool samples were collected from 211 healthy subjects and gut microbial composition was profiled using 16S rRNA amplicon sequencing of the V3-V4 regions. BCs were determined using the Constitution in Chinese Medicine Questionnaire (Wang, 2005). Alpha diversity of QD, PD and DH was inferred and compared against that of Neutral using the Kruskal-Wallis test. Differentially abundant bacterial phyla, family and species were identified by calculating Log2FoldChange of taxa in the unbalanced BCs compared to Neutral. Results There were 135 Neutral, 59 QD, 24 PD and 12 DH subjects. 16 participants exhibited two or more unbalanced BCs. PD exhibited significantly lower alpha diversity (Shannon, Simpson) than Neutral (p<0.05). Fusobacteria (phylum) was elevated in PD (p<0.01). At the species level, Streptococcus gallolyticus was significantly higher in all three unbalanced BCs relative to Neutral. Fusobacterium mortiferum and Sutterella wadsworthensis were higher in PD than Neutral. Faecalitalea spp. was higher in DH than Neutral (IDDF2021-ABS-0140 Figure 1. Log2FoldChange of differentially abundant bacteria in QD, PD and DH as compared to Neutral). Conclusions Varying TCM BCs exhibit unique microbiota signatures. Participants with unbalanced BCs are associated with greater dysbiosis compared to participants with Neutral BC. The lower alpha diversity in PD is consistent with that in obese and metabolic syndrome patients (Stanislawski et al. 2019; Oh et al. 2021). Streptococcus gallolyticus, a species associated with gastrointestinal malignancy (Chand et al. 2016), was significantly higher in all three unbalanced BCs and thus may serve as a potential biomarker for identifying patients with unbalanced BCs.
Background The impact of non-dietary lifestyle factors on the gut microbiota, such as physical activity, has not been frequently reported. Recent studies have suggested that exercise can increase the number of beneficial microbial species which enhance short-chain fatty acid synthesis and carbohydrate metabolism. Therefore, we investigated the relationship between physical activity and gut microbiome composition within a cohort of multi-ethnic healthy Singaporeans. Methods 257 individuals completed the Global Physical Activity Questionnaire (GPAQ) (Armstrong et al. 2006) and Food Frequency Questionnaire (FFQ) (Whitton et al. 2017), to obtain quantitative measures of their physical activity, nutrition and dietary habits, respectively. They also provided paired stool samples, which underwent 16S rRNA V3-4 amplicon sequencing. Community and individual microbial features associated with physical activity were assessed using microbial ecology measures such as α-diversity and principal coordinate analysis (PCA), as well as, multivariate sparse Partial Least Squares analyses, whilst confounding for nutritional and dietary habits. Results Using the GPAQ, 57% of the individuals were deemed to have an active lifestyle. Active individuals have increased microbial α-diversity, although not statistically significant. Unsupervised PCA analysis identified a subset of active individuals with distinct microbiome signatures, whereby these individuals, compared to those with sedentary lifestyles, have increased abundances of Prevotella spp., which is in keeping with their increased fibre intake. Sedentary lifestyle individuals were found to have increased abundance of Lachnoclostridium spp., whereby phylogenetic similar microbial features (such as Roseburia and Subdoligranulum spp.) were significantly correlated with more frequent eating out at hawker stalls and fast-food establishments (IDDF2021-ABS-0169 Figure 1. Correlation between gut microbiome with (a) nutrient intake; and (b) food habit). Studying the metabolic potential of the microbiome, active individuals had increased abundances of gene content related to energy production, whereby sedentary individuals had increased abundances of gene content related to degradation of aromatic compounds. Conclusions Our study reaffirms that increased physical activity is associated with increased microbial diversity and beneficial microbial features. However, the differences in gut microbiota associated with physical activity may be due to differences in dietary intake and practices, rather than the exercise itself. Further studies investigating the link of gut microbiome and physical activity should control and standardize the dietary intake of participants.
Background Singapore and Malaysia are neighbouring countries with similar ethnic make-up: Chinese, Indian, and Malays. However, Singapore is a high-income economy while Malaysia is a middle-income economy. Such a difference has resulted in some levels of dichotomy in diet and lifestyles. In this study, we sought to investigate the gut-ethnic variation across the two neighbouring countries with varying levels of economic development. Methods A total of 439 relatively healthy Malaysian (n=190) and Singaporean (n=249) adults (>18) were included, comprising Chinese (n=240), Indian (n=74), Malay (n=40), and the indigenous Jakun community (n=85). The sequences were processed with DADA2 and annotated using the SILVA database. Results Country of origin explained the most variation in the gut microbiota (PERMANOVA, Pseudo-F=80.798, R2=0.156, p=0.001; IDDF2021-ABS-0150 Figure 1. Ordination). Importantly, ethnicity was still significantly associated with the gut microbiota even after adjusting for the country, age and sex (PERMANOVA, Pseudo-F=4.206, R2=0.019, p=0.001). Several taxa were found to be differentially abundant across ethnicity (ANCOM-BC, q<0.05). Notably, Ligilactobacillus, a lactic acid bacteria, was elevated among Indians (IDDF2021-ABS-0150 Figure 2. Ancom.ci) and reduced among Malay (IDDF2021-ABS-0150 Figure 3. Ancom.cm) relative to Chinese, suggesting that differences in the dietary pattern were responsible for the observed gut variation. Jakun exhibited the most differentially abundant gut microbiota (IDDF2021-ABS-0150 Figure 4. Ancom), with an elevated abundance of 18, 6, 5, and 1 genera, families, order, and class, respectively. The higher diversity of the Jakun was likely a reflection of their more traditional way of life, which has been associated with better gut diversity and health, compared to the Chinese, Indian and Malay of both countries, in particular, the higher abundance of Methanobacteria in Jakun has been inversely associated with irritable bowel syndrome. Conclusions Gut-ethnic differences persist across geographical regions, which was likely due to similar lifestyle and cultural practices by individuals sharing similar ancestry. These signals provide potential biomarkers on the role of the gut microbiota in the aetiology of the unequal disease burdens affecting the different ethnic groups in this multicultural region.
There is growing interest globally in using real-world data (RWD) and real-world evidence (RWE) for health technology assessment (HTA). Optimal collection, analysis, and use of RWD/RWE to inform HTA requires a conceptual framework to standardize processes and ensure consistency. However, such framework is currently lacking in Asia, a region that is likely to benefit from RWD/RWE for at least two reasons. First, there is often limited Asian representation in clinical trials unless specifically conducted in Asian populations, and RWD may help to fill the evidence gap. Second, in a few Asian health systems, reimbursement decisions are not made at market entry; thus, allowing RWD/RWE to be collected to give more certainty about the effectiveness of technologies in the local setting and inform their appropriate use. Furthermore, an alignment of RWD/RWE policies across Asia would equip decision makers with context-relevant evidence, and improve timely patient access to new technologies. Using data collected from eleven health systems in Asia, this paper provides a review of the current landscape of RWD/RWE in Asia to inform HTA and explores a way forward to align policies within the region. This paper concludes with a proposal to establish an international collaboration among academics and HTA agencies in the region: the REAL World Data In ASia for HEalth Technology Assessment in Reimbursement (REALISE) working group, which seeks to develop a non-binding guidance document on the use of RWD/RWE to inform HTA for decision making in Asia.
BACKGROUND:Atrial fibrillation (AF) is the most common heart rhythm disorder and poses a growing disease burden worldwide because of an aging population. A multidisciplinary approach with an emphasis on patient education and self-management has been demonstrated to improve outcomes for AF through the engagement of patients in their own care. Although electronic tools (e-tools) such as apps have been proposed to provide patient education and facilitate self-management, there have been few studies to guide the development of these tools for patients with AF.OBJECTIVE:This study aims to explore the perceptions of patients and health care providers (HCPs) and their attitudes toward the use of e-tools for the self-management of AF. It also seeks to elicit the factors that contribute to these attitudes.METHODS:Semistructured qualitative interviews with HCPs and patients were conducted to understand the interpretations and expectations of an e-tool that would be used for the self-management of AF. Interview data were analyzed using an exploratory thematic analysis approach to uncover emergent themes and infer ideas of preferred features in a device. A modified technology acceptance model was developed as a framework to help interpret these findings. Data from the HCPs and patients were compared and contrasted.RESULTS:Both patients and HCPs thought that an e-tool would be useful in the self-management of AF. Although both groups favored educational content and monitoring of blood pressure, patients expressed more passivity toward self-care and an ambivalence toward the use of technology to monitor their medical condition. This appears to be related to factors such as a patient's age, social support, and their attitudes toward technology. Instead, they favored using the app to contact their HCPs.CONCLUSIONS:This study provides insights into significant differences in the attitudes of patients and HCPs toward the use of e-tools for self-care against their priorities. Understanding patients' motivations and their needs are key to ensuring higher acceptance of such tools.
This paper explores the characteristics of health technology assessment (HTA) systems and practices in Asia. Representatives from nine countries were surveyed to understand each step of the HTA pathway. The analysis finds that although there are similarities in the processes of HTA and its application to inform decision making, there is variation in the number of topics assessed and the stakeholders involved in each step of the process. There is limited availability of resources and technical capacity and countries adopt different means to overcome these challenges by accepting industry submissions or adapting findings from other regions. Inclusion of stakeholders in the process of selecting topics, generating evidence, and making funding recommendations is critical to ensure relevance of HTA to country priorities. Lessons from this analysis may be instructive to other countries implementing HTA processes and inform future research on the feasibility of implementing a harmonized HTA system in the region.
Cell surface antigens are important targets for monoclonal antibodies, but they are often difficult to work with due to their association with the cell membrane. Phage display is a versatile technique that can be applied to generate binders against difficult targets. Here we used antibody phage display to isolate a binder for a rare and specialized cell, the human corneal endothelial cell. The human corneal endothelium is a medically important cell layer; defects in this layer account for about half of all corneal transplants. Despite its importance, no specific antigens have been found to mark this cell type. By panning a phage library directly on human corneal endothelial cells, we isolated an antibody that bound to these cells and not the other types of corneal cells. Subsequently, we identified the antibody's putative target to be CD166 by immunoprecipitation and mass spectrometry. This approach can be used to isolate antibodies against other poorly-characterized cell types, such as stem cells or cancer cells, without any prior knowledge of their discriminating markers.
IgA nephropathy (IgAN) is one of the most common primary glomerulonephritis. Previously identified genome-wide association study (GWAS) loci explain only a fraction of disease risk. To identify novel susceptibility loci in Han Chinese, we conduct a four-stage GWAS comprising 8,313 cases and 19,680 controls. Here, we show novel associations at ST6GAL1 on 3q27.3 (rs7634389, odds ratio (OR)=1.13, P=7.27 × 10(-10)), ACCS on 11p11.2 (rs2074038, OR=1.14, P=3.93 × 10(-9)) and ODF1-KLF10 on 8q22.3 (rs2033562, OR=1.13, P=1.41 × 10(-9)), validate a recently reported association at ITGAX-ITGAM on 16p11.2 (rs7190997, OR=1.22, P=2.26 × 10(-19)), and identify three independent signals within the DEFA locus (rs2738058, P=1.15 × 10(-19); rs12716641, P=9.53 × 10(-9); rs9314614, P=4.25 × 10(-9), multivariate association). The risk variants on 3q27.3 and 11p11.2 show strong association with mRNA expression levels in blood cells while allele frequencies of the risk variants within ST6GAL1, ACCS and DEFA correlate with geographical variation in IgAN prevalence. Our findings expand our understanding on IgAN genetic susceptibility and provide novel biological insights into molecular mechanisms underlying IgAN.
Nat. Genet. 47, 387–392 (2015); published online 23 February 2015; corrected online 9 March 2015; corrected after print 27 April 2015 In the version of this article initially published, the name of author Afsaneh Naderi Beni was misspelled. The error has been corrected in the HTML and PDF versions of the article.