Community-wide Scale Research Articles

Impact of the COVID-19 Pandemic on Cancer Diagnosis in Madrid (Spain) Based on the RTMAD Tumor Registry (2019–2021)

The coronavirus disease 2019 (COVID-19) pandemic has caused a significant disruption to cancer diagnosis, treatment and prevention worldwide that could have serious consequences in the near future. We intend to evaluate the weight of this backlog on a community-wide scale in Madrid during the period 2020-2021, and whether a stage shift towards the advanced stage has occurred. Cancer diagnoses in the Madrid tumor registry (RTMAD) from 2019-2021 were evaluated. Absolute and percentage differences in annual volume and observed-to-expected (O/E) volume ratios were calculated. Standardized incidence ratios (SIRs) and 95% confidence intervals (CIs) were calculated using the O/E ratio. The SIR for 2020-2021 compared to 2019 was 94.5% (95% CI 93.8-95.3), with unequal gender-specific cancer diagnosis recovery (88.5% for males and 102.1% for females). Most cancer types were underdiagnosed in 2020. The tendency worsened in 2021 for colorectal and prostate cancers (87.8%), but lung cancer recovered (102.1%) and breast cancer was over-diagnosed (114.4%) compared with reference pre-COVID-19 data. These changes have modified the ranking of the most frequent malignancies diagnosed in Madrid. Breast cancer has overtaken colorectal and prostate cancers, displaced to second and third position, respectively. Not only was colorectal cancer diagnosis affected more as a consequence of the COVID-19 pandemic but diagnosis of this malignancy at the advance stage also increased by 3.6% in 2020 and 4.2% in 2021 compared to the reference period of 2019. In summary, there is a large volume of undetected cancer in Madrid caused by the reduced access to care secondary to the COVID-19 pandemic, especially regarding colorectal and prostate cancer. Strategies are needed to recover the backlog of diagnoses and effectively treat these cases in the future and solve the negative impact that will be caused by the diagnostic delay. Analyzing the impact of new diagnoses suffered by each different malignancy and their recovery will help to understand how the future allocation of resources should look.

To Ring or Not to Ring: What COVID-19 Taught Us about Religious Heritage Soundscapes in the Community

Despite church bell ringing being directly influenced by purposive human action, often as a liturgical function, it creates a community soundscape with ascribed heritage values. While general heritage management processes and decisions are informed by heritage professionals with a broader range of experience, we find that church bell ringing is contrary to this process. The COVID-19 pandemic has demonstrated how a stochastic disruptive event can dramatically alter soundscapes on a community-wide scale. Here, the effective power over bell ringing often rested with the individual clergy at the local level and is subject to that individual’s personal preferences. This has serious implications to non-traditional forms of heritage, such as intangible sounds and soundscapes. In realizing the value of sound signals and soundmarks, we highlight the need to formally recognize these sounds of religious settings and consider them in heritage frameworks.

How Do Quorum-Sensing Signals Mediate Algae-Bacteria Interactions?

Quorum sensing (QS) describes a process by which bacteria can sense the local cell density of their own species, thus enabling them to coordinate gene expression and physiological processes on a community-wide scale. Small molecules called autoinducers or QS signals, which act as intraspecies signals, mediate quorum sensing. As our knowledge of QS has progressed, so too has our understanding of the structural diversity of QS signals, along with the diversity of bacteria conducting QS and the range of ecosystems in which QS takes place. It is now also clear that QS signals are more than just intraspecies signals. QS signals mediate interactions between species of prokaryotes, and between prokaryotes and eukaryotes. In recent years, our understanding of QS signals as mediators of algae–bacteria interactions has advanced such that we are beginning to develop a mechanistic understanding of their effects. This review will summarize the recent efforts to understand how different classes of QS signals contribute to the interactions between planktonic microalgae and bacteria in our oceans, primarily N-acyl-homoserine lactones, their degradation products of tetramic acids, and 2-alkyl-4-quinolones. In particular, this review will discuss the ways in which QS signals alter microalgae growth and metabolism, namely as direct effectors of photosynthesis, regulators of the cell cycle, and as modulators of other algicidal mechanisms. Furthermore, the contribution of QS signals to nutrient acquisition is discussed, and finally, how microalgae can modulate these small molecules to dampen their effects.

Literature on peer-based community physical activity programmes for mental health service users: a scoping review

ABSTRACT Physical activity is a key determinant of mental health; community programmes aim to increase health and well-being on a community wide scale with emphasis on social interaction. Regular physical activity participation in community settings yields additional social benefits, such as peer support. This scoping review aimed to explore existing literature that has included peer support as a component of community-based physical activity programmes for MHSU. Published literature was examined using electronic databases (SportDiscus, Web of Science, MEDLINE, and PsycINFO), reference lists, and hand searching of journals. Thirteen eligible articles included; adults aged 18 and over, a peer support component, physical activity and/or sport, participants with mental health diagnoses and were community-based. Research published between 2007 and 2019, peer-reviewed and written in English was included. Nine studies found a significant increase in perceived social support, seven studies reported increased mental wellbeing and five studies reported increased physical activity levels. Effectiveness of reviewed programmes were categorised as; overall improvements in physical activity levels, improvements to mental health, exercise related psychosocial benefits, knowledge relating to self-care, and improved social connections. Community-based physical activity programmes produced psychosocial benefits and positive behaviour change for MHSU, warranting greater focus towards implementing effective peer support into community programmes.

Spatio-temporal dynamics of seedling communities are determined by seed input and habitat filtering in a subtropical montane forest

Spatial and temporal variation in species abundances and distributions of the seedling community, which plays a pivotal role in maintaining species diversity, can help predict future changes in forest communities. We monitored the dynamics of 12,830 seedlings within 405 1-m2 seedling plots in the Badagongshan (BDGS) 25-ha forest dynamic plot over a 6-year period (2012–2017). We presented changes in the relative abundance for 15 dominant seedling species during the last six years, assessed temporal changes in species richness, species turnover, seedling density, species reordering (mean rank shift of the relative abundance; MRS) and community similarity within three topographically defined habitats (ridge, slope and valley), and explored the mechanisms underlying dynamics of seedling communities. Furthermore, we explored differences in species’ ecological indicator values (EIVs) and functional groups for species gained and lost during the study period. Across three habitat types, there were enormous reordering of the 15 dominant seedling species; a few mast-seedling events were clearly identified. Both species richness and seedling density continually declined over the entire census year, except for an increase of species richness during 2012–2013. Species turnover fluctuated temporally in three habitat types; overall, species emigration rate was higher than species immigration rate in three habitats. Valleys with lower soil C:N ratio, light availability and VDCN (vertical distance above the channel network), but higher soil pH and TWI (topographic wetness index), had lower species richness and stem density, and higher species turnover and species reordering than slopes and ridges. At the community-wide scale, significant directional changes in species composition occurred on ridges and slopes. Newly colonizing species were typically more shade- tolerant, water- and temperature- demanding shrub species and grown on soil with low pH but high fertility. In the BDGS plot, species richness and seedling density fluctuated in the first two years and then decreased over time, which reflects that both habitat filtering and seed input regulated temporal dynamics of species composition, but the relative importance varied among studied years. In this subtropical forest, species composition showed obvious directional changes. Shrub species increased more than species of other strata in ridge and slope areas. It is worth noting that an increased dominance of species that are more water-demanding could increase the risk of mortality under global climate change (e.g. drought).

Quantifying e-bike applicability by comparing travel time and physical energy expenditure: A case study of Japanese cities

BackgroundE-bikes are a growing market around the world and public policies regarding their usage are varied among cities. There is a need to inform policy decisions about integrating e-bikes into urban transportation systems. While previous studies on bicycle convenience focused on the cycling environment itself, assessment of a new transport mode, like e-bikes, requires insights into their potential and limitations when introduced into the existing urban transportation system. MethodsE-bike applicability is defined as the change of convenience due to their introduction and the service area is adopted as a measure of convenience for a transportation mode. Indices for e-bike applicability are proposed by comparing the service area of e-bikes to public transit and to conventional bicycles considering travel time and physical energy expenditure as two measures. The methods are applied to four Japanese cities to assess applicability on two scales, namely a community-wide scale and a city-wide scale. ResultsOn the community-wide scale, e-bikes are applicable to areas with steep road gradients, areas with geographical obstacles requiring detours, and areas lacking public transportation. E-bike applicable communities with high likely e-bike demand are selected. On the city-wide scale, e-bikes are applicable to short distance trips in cities with well-developed transit systems, with applicable travel time and physical energy expenditure range of 65 min and 1.25 MET-h round trip, respectively. E-bikes are a promising alternative means of transport in local cities; they also have limitation in terms of physical energy expenditure compared to transit. ConclusionsThe indices can be valuable tools providing urban planners with knowledge about e-bikes on a community-wide scale and a city-wide scale.

An ultra-high-performance liquid chromatography tandem mass spectrometry method for oxidative stress biomarker analysis in wastewater

Reported herein is the development of an analytical method for the detection of four oxidative stress biomarkers in wastewater using ultra-high-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS) and solid phase extraction (SPE). The following four biomarkers of oxidative stress and lipid peroxidation have been investigated: hydroxynonenal–mercapturic acid (HNE-MA), 8-iso-prostglandin F2beta (8-iso-PGF2β), 8-nitroguanine (8-NO2Gua) and 8-hydroxy-2-deoxyguanosine (8-OHdG). The method showed very good performance: accuracy (> 87%), precision (> 90%), method quantification limits (1.3–3.0 ng L−1) and biomarker stability in wastewater in the case of HNE-MA, 8-OHdG and 8-iso-PGF2β. In contrast, 8-NO2Gua was found to be less stable in wastewater, which affected its method performance: accuracy (> 63%), precision (> 91%) and method quantification limits (85.3 ng L−1). Application of the developed method resulted in, for the first time, HNE-MA being successfully observed and quantified within wastewater over a study period of a week (displayed average daily loads per capita of 48.9 ± 4.1 mg/1000/people/day). 8-iso-PGF2β was detected with good intensity but could not be quantified due to co-elution with other isomers. 8-OHdG was detected, albeit at < MQL. This study demonstrates the potential for expanding on the possible endogenous biomarkers of health used in urban water fingerprinting to aid in measuring health in near-real time on a community-wide scale.

Translating Comparative Effectiveness Research Into Practice: Effects of Interventions on Lifestyle, Medication Adherence, and Self-care for Type 2 Diabetes, Hypertension, and Obesity Among Black, Hispanic, and Asian Residents of Chicago and Houston, 2010 to 2013.

In the United States, racial/ethnic minorities account for disproportionate disease and death from type 2 diabetes, hypertension, and obesity; however, interventions with measured efficacy in comparative effectiveness research are often not adopted or used widely in those communities. To assess implementation and effects of comparative effectiveness research-proven interventions translated for minority communities. Mixed-method assessment with pretest-posttest single-group evaluation design. US Department of Health and Human Services, Office of Minority Health, research contractor, and advisory board; health centers, including a federally qualified community health center in Chicago, Illinois; and public housing facilities for seniors in Houston, Texas. A total of 97 black, Hispanic, and Asian participants with any combination of health care provider-diagnosed type 2 diabetes, hypertension, or obesity. Virtual training institutes where intervention staff learned cultural competency methods of adapting effective interventions. Health educators delivered the Health Empowerment Lifestyle Program (HELP) in Chicago; community pharmacists delivered the MyRx Medication Adherence Program in Houston. Participation rates, satisfaction with interventions during January to April 2013, and pre- to postintervention changes in knowledge, diet, and clinical outcomes were analyzed through July 2013. In Chicago, 38 patients experienced statistically significant reductions in hemoglobin A1c and systolic blood pressure, increased knowledge of hypertension management, and improved dietary behaviors. In Houston, 38 subsidized housing residents had statistically nonsignificant improvements in knowledge of self-management and adherence to medication for diabetes and hypertension but high levels of participation in pharmacist home visits and group education classes. Adaptation, adoption, and implementation of HELP and MyRx demonstrated important postintervention changes among racial/ethnic participants in Chicago and Houston. The communities faced similar implementation challenges across settings, targets of change, and cities. Available resources were insufficient to sustain benefits with measurable impact on racial/ethnic disparities beyond the study period. Results suggest the need for implementation studies of longer duration, greater power, and salience to policies and programs that can sustain longterm interventions on a community-wide scale.

Regional synchrony in full-scale activated sludge bioreactors due to deterministic microbial community assembly.

Seasonal community structure and regionally synchronous population dynamics have been observed in natural microbial ecosystems, but have not been well documented in wastewater treatment bioreactors. Few studies of community dynamics in full-scale activated sludge systems facing similar meteorological conditions have been done to compare the importance of deterministic and neutral community assembly mechanisms. We subjected weekly activated sludge samples from six regional full-scale bioreactors at four wastewater treatment plants obtained over 1 year to Illumina sequencing of 16S ribosomal RNA genes, resulting in a library of over 17 million sequences. All samples derived from reactors treating primarily municipal wastewater. Despite variation in operational characteristics and location, communities displayed temporal synchrony at the individual operational taxonomic unit (OTU), broad phylogenetic affiliation and community-wide scale. Bioreactor communities were dominated by 134 abundant and highly regionally synchronized OTU populations that accounted for over 50% of the total reads. Non-core OTUs displayed abundance-dependent population synchrony. Alpha diversity varied by reactor, but showed a highly reproducible and synchronous seasonal fluctuation. Community similarity was dominated by seasonal changes, but individual reactors maintained minor stable differences after 1 year. Finally, the impacts of mass migration driven by direct biomass transfers between reactors was investigated, but had no significant effect on community similarity or diversity in the sink community. Our results show that population dynamics in activated sludge bioreactors are consistent with niche-driven assembly guided by seasonal temperature fluctuations.

A crucial role for spatial distribution in bacterial quorum sensing

Quorum sensing (QS) is a process that enables bacteria to communicate using secreted signaling molecules, and then makes a population of bacteria to regulate gene expression collectively and control behavior on a community-wide scale. Theoretical studies of efficiency sensing have suggested that both mass-transfer performance in the local environment and the spatial distribution of cells are key factors affecting QS. Here, an experimental model based on hydrogel microcapsules with a three-dimensional structure was established to investigate the influence of the spatial distribution of cells on bacterial QS. Vibrio harveyi cells formed different spatial distributions in the microcapsules, i.e., they formed cell aggregates with different structures and sizes. The cell aggregates displayed stronger QS than did unaggregated cells even when equal numbers of cells were present. Large aggregates (LA) of cells, with a size of approximately 25 μm, restricted many more autoinducers (AIs) than did small aggregates (SA), with a size of approximately 10 μm, thus demonstrating that aggregate size significantly affects QS. These findings provide a powerful demonstration of the fact that the spatial distribution of cells plays a crucial role in bacterial QS.

Creativity in an Online Community as a Response to the Chaos of a Breast Cancer Diagnosis

Creativity in an Online Community as a Response to the Chaos of a Breast Cancer Diagnosis

Modelling the performance of isoniazid preventive therapy for reducing tuberculosis in HIV endemic settings: the effects of network structure

Individuals living with HIV experience a much higher risk of progression from latent M. tuberculosis infection to active tuberculosis (TB) disease relative to individuals with intact immune systems. A several-month daily course of a single drug during latent infection (i.e. isoniazid preventive therapy (IPT)) has proved in clinical trials to substantially reduce an HIV-infected individual's risk of TB disease. As a result of these findings and ongoing studies, the World Health Organization has produced strong guidelines for implementing IPT on a community-wide scale for individuals with HIV at risk of TB disease. To date, there has been limited use of IPT at a community-wide level. In this paper, we present a new co-network model for HIV and TB co-epidemics to address questions about how the population-level impact of community-wide IPT may differ from the individual-level impact of IPT offered to selected individuals. In particular, we examine how the effect of clustering of contacts within high-TB incidence communities may affect the rates of re-infection with TB and how this clustering modifies the expected population-level effects of IPT. We find that populations with clustering of respiratory contacts experience aggregation of TB cases and high numbers of re-infection events. While, encouragingly, the overall population-level effects of community-wide IPT appear to be sustained regardless of network structure, we find that in populations where these contacts are highly clustered, there is dramatic heterogeneity in the impact of IPT: in some sub-regions of these populations, TB is nearly eliminated, while in others, repeated re-infection almost completely undermines the effect of IPT. Our findings imply that as IPT programmes are brought to scale, we should expect local heterogeneity of effectiveness as a result of the complex patterns of disease transmission within communities.

MzServer: Web-based Programmatic Access for Mass Spectrometry Data Analysis

Continued progress toward systematic generation of large-scale and comprehensive proteomics data in the context of biomedical research will create project-level data sets of unprecedented size and ultimately overwhelm current practices for results validation that are based on distribution of native or surrogate mass spectrometry files. Moreover, the majority of proteomics studies leverage discovery-mode MS/MS analyses, rendering associated data-reduction efforts incomplete at best, and essentially ensuring future demand for re-analysis of data as new biological and technical information become available. Based on these observations, we propose to move beyond the sharing of interpreted spectra, or even the distribution of data at the individual file or project level, to a system much like that used in high-energy physics and astronomy, whereby raw data are made programmatically accessible at the site of acquisition. Toward this end we have developed a web-based server (mzServer), which exposes our common API (mzAPI) through very intuitive (RESTful) uniform resource locators (URL) and provides remote data access and analysis capabilities to the research community. Our prototype mzServer provides a model for lab-based and community-wide data access and analysis.

Prevalence of clinical venous thromboembolism in the USA: Current trends and future projections

The U.S.-wide prevalence of venous thromboembolism (VTE) is unclear, with reported VTE incidence estimates varying widely. This retrospective analysis of healthcare claims data from patients in the Thomson Reuters national MarketScan(®) Commercial and Medicare databases (January 2002-December 2006) estimates the U.S. prevalence of VTE, and assesses associated temporal trends. Of 12.7 million study-eligible patients, 200,007 had VTE. The overall prevalence of VTE (cases per 100,000) increased by 33.1% during the study period: from 317 in 2002 to 422 in 2006. VTE was more prevalent in women than men throughout the study. The annual prevalence of VTE increased with age: 1,382 in patients ≥65 years versus 231 in patients <65 (2006 data). The number of U.S. adults with VTE is projected to more than double from 0.95 million in 2006 to 1.82 million in 2050. These data confirm that VTE remains a major healthcare burden in the US, particularly among the elderly, and highlight a continuing increase in prevalence of the disease. Greater efforts are required to improve awareness of VTE and improve standards of VTE prevention in healthcare organizations.

The sin of untrustworthy financial behaviour: the American experience, 1985-2010

It is the position of this paper that recent financial crises have been amplified, if not created, by the sin of professional financial untrustworthiness. Trust is the bedrock of financial behaviour and without trust, financial markets fail as efficient resource allocators. Sin is identified as ethical failure on a communitywide scale. Between 1985 and 2010, the USA has experienced five major financial crises that have explicitly cost the taxpayer more than all wars since Vietnam. This paper identifies the emphasis on transactions fees as the operational vehicle behind these crises and discusses a few potential remedies.

Understanding critical infrastructure failure: examining the experience of Biloxi and Gulfport, Mississippi after Hurricane Katrina

This article examines disaster recovery and resilience issues following a major hurricane. Two coastal communities were chosen for study following Hurricane Katrina in order to explore the issues in measuring and evaluating recovery and resilience. The communities were Biloxi and Gulfport, Mississippi. A mix of data sources was employed to determine effects on critical infrastructure on a community-wide scale. The data sources included key informant interviews, Geographic Information System (GIS) data and secondary data such as newspaper reports, city financial statements and similar documents. The key findings indicate a methodological problem with the formulation of recovery and resilience curves as discussed in other literature. While information regarding a particular community can be mapped, its characteristics are unique and difficult to generalise to other communities. While this issue is not necessarily new to the area of hazards research, it adds weight to the argument that more should be done to collect postevent data that can be analysed in a cross-comparative way with other communities. Recommendations include the establishment of a 'data archivist' position that would be collocated in an Emergency Operations Center (EOC), and the development of standardised measurement sets that all disaster-affected communities would gather post event. Finally, specific recommendations for further research are offered.

Societal interactions in ovarian cancer metastasis: a quorum-sensing hypothesis

The biochemical and biological mechanisms metastatic cancer cells use to function as communities and thwart internal and external growth control mechanisms remain undefined. In this work, we present the hypothesis that cancer cells may use a Quorum-Sensing mechanism to regulate multicellular functions and control steps in metastatic colonization. Quorum sensing is a bacterial cell-cell communication process used to track increasing cell-population density and, in response to changes in cell number, coordinate gene expression and behavior on a community-wide scale. Important parallels between the behavior of societies of bacterial cells and societies of malignant cancer cells exist in the bacterial literature. Of relevance to metastasis is the finding that pathogenic bacteria use quorum sensing to determine when their population numbers are high enough to collectively form biofilms in or on host organisms. Biofilms are complex, heterogeneous communities of bacterial cells encased within an extracellular matrix attached to a solid surface. Biofilms exacerbate disease and are refractory to a battery of therapies. We suggest that the quorum-sensing-controlled bacterial biofilm formation process closely parallels the steps in metastatic colonization. Cells migrate toward/on target surfaces (organ-specific homing), show cell-cell and cell-matrix interactions (tumor cell-stromal cell crosstalk), remain subclinical until they can mount an effective attack (dormancy), form complex structures with channels for nutrient flow (vascularized lesions), and contain resistant cells which can cause disease recurrence (persistors). Using ovarian cancer as an example, we present data supporting the connection between metastatic colonization and quorum sensing and discuss the implications for understanding and controlling metastasis formation.

Eliciting Contraband through Archaeology: Illicit Trade in Eighteenth-Century St. Augustine

The study of contraband (illicit trade) should offer a uniquely appropriate focus for the multi-evidentiary strengths of historical archaeology, in that it demands the articulation of largely undocumented economic activity (reflected materially in archaeological remains) with legal mandates and formal regulations about commerce. Problematic issues in realizing this are presented by the recognition of contraband goods and activities in the archaeological record and by the difficulties in articulating archaeologically derived periodicity with text-based periodicity of contraband in a given community. With those concerns in mind, the analysis of excavated data from six 18th-century households of St. Augustine is described here with extensive historical documentation of contraband activity in Spanish Florida and the Spanish Americas in general to explore the notion that historical archaeological integration of data about contraband can reveal useful information not knowable from either source alone. Results suggest that at a community-wide scale of analysis, the archaeological data essentially reify and add detail to the already existing documentary accounts of contraband trade. A household scale of analysis and comparison reveals how people with specific economic, occupational, religious, ethnic, and social identities engaged in contraband as a strategy in ways that were not previously known. This helps define the contours of economic possibility and creates a more nuanced understanding of the structure, opportunity, and dynamics of economic choice and agency within a community.

Introduction: Spirituality and Catastrophe

In this issue, the focus of the Southern MediccilJownaV s Spirituality/Medicine Interface Project is on what physicians need to know about spirituality and mass catastrophe. As used here, spirituality involves religious beliefs, practices, and traditions, but also more broadly includes a search for the sacred,' ultimate truth, or ultimate reality. Spirituality is closely related to but distinct from concepts such as meaning and purpose in life, connectedness to others, and sense of peacefijlness to which spiritual strivings may eventually lead but arc not part of the definition itself.' Mass catastrophes include natural disasters (eg, hurricanes) and acts of human terrorism (eg, bombings) that affect entire communities; these contrast with personal catastrophes (eg, murder, infidelity, torture, disfigurement). Catastrophe as discussed here will be limited to disaster on a communitywide scale. The purpose of these articles is to prepare physicians to address the unique emotional, social, and spiritual needs of survivors and of their families, of rescue workers, and of the treating physicians themselves. Besides generally preparing physicians to meet the medical and psychological needs of survivors, this issue will help to increase awareness of the spiritual needs of these potential patients, to learn how to sensitively identify those needs, and to detemiine when and whom to refer. The role that religion and spirituality play in helping survivors cope with the trauma of disasters is ofren quite significant. The ultimate result, we hope, will be a nation that is more resilient during times of catastrophe.

Phosphorylation and Processing of the Quorum-Sensing Molecule Autoinducer-2 in Enteric Bacteria

Quorum sensing is a process of chemical communication that bacteria use to assess cell population density and synchronize behavior on a community-wide scale. Communication is mediated by signal molecules called autoinducers. The LuxS autoinducer synthase produces 4,5-dihydroxy-2,3-pentanedione (DPD), the precursor to a set of interconverting molecules that are generically called autoinducer-2 (AI-2). In enteric bacteria, AI-2 production induces the assembly of a transport apparatus (called the LuxS regulated (Lsr) transporter) that internalizes endogenously produced AI-2 as well as AI-2 produced by other bacterial species. AI-2 internalization is proposed to be a mechanism enteric bacteria employ to interfere with the signaling capabilities of neighboring species of bacteria. We have previously shown that Salmonella enterica serovar Typhimurium binds a specific cyclic derivative of DPD. Here we show that following internalization, the kinase LsrK phosphorylates carbon-5 of the open form of DPD. Phosphorylated DPD (P-DPD) binds specifically to the repressor of the lsr operon, LsrR, consistent with P-DPD being the inducer of the lsr operon. Subsequently, LsrG catalyzes the cleavage of P-DPD producing 2-phosphoglycolic acid. This series of chemical events is proposed to enable enteric bacteria to respond to the presence of competitor bacteria by sequestering and destroying AI-2, thereby eliminating the competitors' intercellular communication capabilities.