Single-strain behavior predicts responses to environmental pH and osmolality in the gut microbiota.

Changes to gut environmental factors such as pH and osmolality due to disease or drugs correlate with major shifts in microbiome composition; however, we currently cannot predict which species can tolerate such changes or how the community will be affected. Here, we assessed the growth of 92 representative human gut bacterial strains spanning 28 families across multiple pH values and osmolalities in vitro. The ability to grow in extreme pH or osmolality conditions correlated with the availability of known stress response genes in many cases, but not all, indicating that novel pathways may participate in protecting against acid or osmotic stresses. Machine learning analysis uncovered genes or subsystems that are predictive of differential tolerance in either acid or osmotic stress. For osmotic stress, we corroborated the increased abundance of these genes in vivo during osmotic perturbation. The growth of specific taxa in limiting conditions in isolation in vitro correlated with survival in complex communities in vitro and in an in vivo mouse model of diet-induced intestinal acidification. Our data show that in vitro stress tolerance results are generalizable and that physical parameters may supersede interspecies interactions in determining the relative abundance of community members. This study provides insight into the ability of the microbiota to respond to common perturbations that may be encountered in the gut and provides a list of genes that correlate with increased ability to survive in these conditions. IMPORTANCE To achieve greater predictability in microbiota studies, it is crucial to consider physical environmental factors such as pH and particle concentration, as they play a pivotal role in influencing bacterial function and survival. For example, pH is significantly altered in various diseases, including cancers, inflammatory bowel disease, as well in the case of over-the-counter drug use. Additionally, conditions like malabsorption can affect particle concentration. In our study, we investigate how changes in environmental pH and osmolality can serve as predictive indicators of bacterial growth and abundance. Our research provides a comprehensive resource for anticipating shifts in microbial composition and gene abundance during complex perturbations. Moreover, our findings underscore the significance of the physical environment as a major driver of bacterial composition. Finally, this work emphasizes the necessity of incorporating physical measurements into animal and clinical studies to better understand the factors influencing shifts in microbiota abundance.

Microbial endocrinology: the mechanisms by which the microbiota influences host sex steroids.

Recent progress in microbial endocrinology has propelled this field from initially providing correlational links to defining the mechanisms by which microbes influence systemic sex hormones. Importantly, the interaction between the gut-resident bacteria and host-secreted hormones has been shown to be critical for host development as well as hormone-mediated disease progression. This review investigates how microbes affect active sex hormone levels, with a focus on gut-associated bacteria hormonal modifications and the resulting host physiological status. Specifically, we focus on the ability of the microbiota to reactivate estrogens and deactivate androgens and thereby influence systemic levels of host hormones in a clinically significant manner.

The public health role of caseloading midwives in advancing health equity in childbearing women and babies living in socially deprived areas in England: The Mi-CARE Study protocol.

This article outlines the protocol for a qualitative Constructivist Grounded Theory study, examining the public health role of caseloading midwives working in a continuity model of care in areas of urban social deprivation. The study is currently being conducted in a city in the south of England during the COVID-19 pandemic. Focusing specifically on the Social Determinants of Health impacting women and babies in this context and from the perspectives of women themselves, the study is developing a theoretical framework examining the actions caseloading midwives take in response to these determinants and how these actions contribute to advancing equity and equality for women and babies at increased risk of adverse perinatal outcomes. Examining and integrating the experiences of women and midwives from a Constructivist Grounded Theory perspective, the study findings will inform current NHS maternity policy and contribute to our understanding about the social processes and mechanisms underpinning the known benefits of midwifery continuity of care models in different contexts.

Web-based internet searches for digital health products in the United Kingdom before and during the COVID-19 pandemic: a time-series analysis using app libraries from the Organisation for the Review of Care and Health Applications (ORCHA).

OBJECTIVES: To explore if consumer interest in digital health products (DHPs), changed following the COVID-19 pandemic and the lockdown measures that ensued. DESIGN: Retrospective time-series analysis of web-based internet searches for DHPs in the UK, split over two periods, pre-COVID-19 lockdown (January 2019-23 March 2020) and post-COVID-19 lockdown (24 March 2020-31 December 2020). SETTING: The UK. PARTICIPANTS: Members of the UK general population using health-app libraries provided by the Organisation for the Review of Care and Health Applications. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome was volume of searches for DHPs. Secondary outcomes considered search volumes for 25 different therapeutic areas. Outcomes were assessed for significance using a two-stage Poisson test. RESULTS: There were 126 640 searches for DHPs over the study period. Searches for DHPs increased by 343% from 2446 per month prior to COVID-19 lockdown measures being introduced to 8996 per month in the period following the first COVID-19 lockdown in the UK. In total, 23/25 (92%) of condition areas experienced a significant increase in searches for DHPs, with the greatest increases occurring in the first 2 months following lockdown. Musculoskeletal conditions (2.036%), allergy (1.253%) and healthy living DHPs (1.051%) experienced the greatest increases in searches compared with pre-lockdown. Increased search volumes for DHPs were sustained in the 9 months following the introduction of lockdown measures, with 21/25 (84%) of condition areas experiencing monthly search volumes at least 50% greater than pre-lockdown levels. CONCLUSIONS: The COVID-19 pandemic has profoundly disrupted the routine delivery of healthcare, making face-to-face interaction difficult, and contributing to unmet clinical needs. This study has demonstrated significant increases in internet searches for DHPs by members of the UK population since COVID-19, signifying an increased interest in this potential therapeutic medium. Future research should clarify whether this increased interest has resulted in increased acceptance and utilisation of these technologies also.