Search

Objective: To conduct cross-country comparisons and assess the effect of foreign birth on access to primary and preventive care in Canada and the United States.Data Sources: Secondary data from the 2002 to 2003 Joint Canada-United States Survey of Health.Study Design: Descriptive and comparative analyses were conducted, and logistic regression models were used to assess the effect of immigrant status and country of residence on access to care. Outcomes included measures of health care systems and processes, utilization, and patient perceptions.Principal Findings: In adjusted analyses, immigrants in Canada fared worse than nonimmigrants regarding having timely Pap tests; in the United States, immigrants fared worse for having a regular doctor and an annual consultation with a health professional. Immigrants in Canada had better access to care than immigrants in the United States; most of these differences were explained by differences in socioeconomic status and insurance coverage across the two countries. However, U.S. immigrants were more likely to have timely Pap tests than Canadian immigrants, even after adjusting for potential confounders.Conclusions: In both countries, foreign-born populations had worse access to care than their native-born counterparts for some indicators but not others. However, few differences in access to care were found when direct cross-country comparisons were made between immigrants in Canada versus the United States, after accounting for sociodemographic differences. [ABSTRACT FROM AUTHOR]

Background: Alterations to the gut microbiome have been linked to multiple chronic diseases. However, the drivers of such changes remain largely unknown. The oral cavity acts as a major route of exposure to exogenous factors including pathogens, and processes therein may affect the communities in the subsequent compartments of the gastrointestinal tract. Here, we perform strain-resolved, integrated meta-genomic, transcriptomic, and proteomic analyses of paired saliva and stool samples collected from 35 individuals from eight families with multiple cases of type 1 diabetes mellitus (T1DM)., Results: We identified distinct oral microbiota mostly reflecting competition between streptococcal species. More specifically, we found a decreased abundance of the commensal Streptococcus salivarius in the oral cavity of T1DM individuals, which is linked to its apparent competition with the pathobiont Streptococcus mutans. The decrease in S. salivarius in the oral cavity was also associated with its decrease in the gut as well as higher abundances in facultative anaerobes including Enterobacteria. In addition, we found evidence of gut inflammation in T1DM as reflected in the expression profiles of the Enterobacteria as well as in the human gut proteome. Finally, we were able to follow transmitted strain-variants from the oral cavity to the gut at the individual omic levels, highlighting not only the transfer, but also the activity of the transmitted taxa along the gastrointestinal tract., Conclusions: Alterations of the oral microbiome in the context of T1DM impact the microbial communities in the lower gut, in particular through the reduction of "mouth-to-gut" transfer of Streptococcus salivarius. Our results indicate that the observed oral-cavity-driven gut microbiome changes may contribute towards the inflammatory processes involved in T1DM. Through the integration of multi-omic analyses, we resolve strain-variant "mouth-to-gut" transfer in a disease context. Video Abstract., (© 2022. The Author(s).)

The development of reliable, mixed-culture biotechnological processes hinges on understanding how microbial ecosystems respond to disturbances. Here we reveal extensive phenotypic plasticity and niche complementarity in oleaginous microbial populations from a biological wastewater treatment plant. We perform meta-omics analyses (metagenomics, metatranscriptomics, metaproteomics and metabolomics) on in situ samples over 14 months at weekly intervals. Based on 1,364 de novo metagenome-assembled genomes, we uncover four distinct fundamental niche types. Throughout the time-series, we observe a major, transient shift in community structure, coinciding with substrate availability changes. Functional omics data reveals extensive variation in gene expression and substrate usage amongst community members. Ex situ bioreactor experiments confirm that responses occur within five hours of a pulse disturbance, demonstrating rapid adaptation by specific populations. Our results show that community resistance and resilience are a function of phenotypic plasticity and niche complementarity, and set the foundation for future ecological engineering efforts.

Aplysina aerophoba is an emerging model marine sponge, with a well-characterized microbial community in terms of diversity and structure. However, little is known about the expressed functional capabilities of its associated microbes. Here, we present the first metaproteomics-based study of the microbiome of A. aerophoba. We found that transport and degradation of halogenated and chloroaromatic compounds are common active processes in the sponge microbiomes. Our data further reveal that the highest number of proteins were affiliated to a sponge-associated Tectomicrobium, presumably from the family Entotheonellaceae, as well as to the well-known symbiont "Candidatus Synechococcus spongiarium", suggesting a high metabolic activity of these two microorganisms in situ. Evidence for nitric oxide (NO) conversion to nitrous oxide was consistently observed for Tectomicrobia across replicates, by production of the NorQ protein. Moreover, we found a potential energy-yielding pathway through CO oxidation by putative Chloroflexi bacteria. Finally, we observed expression of enzymes that may be involved in the transformation of chitin, glycoproteins, glycolipids and glucans into smaller molecules, consistent with glycosyl hydrolases predicted from analyses of the genomes of Poribacteria sponge symbionts. Thus, this study provides crucial links between expressed proteins and specific members of the A. aerophoba microbiome.

The Gram-negative beta-proteobacterium Zoogloea sp. LCSB751 (LMG 29444) was newly isolated from foaming activated sludge of a municipal wastewater treatment plant. Here, we describe its draft genome sequence and annotation together with a general physiological and genomic analysis, as the first sequenced representative of the Zoogloea genus. Moreover, Zoogloea sp. gene expression in its environment is described using metatranscriptomic data obtained from the same treatment plant. The presented genomic and transcriptomic information demonstrate a pronounced capacity of this genus to synthesize poly-β-hydroxyalkanoate within wastewater.

Linking taxonomic identity and functional potential at the population-level is important for the study of mixed microbial communities and is greatly facilitated by the availability of microbial reference genomes. While the culture-independent recovery of population-level genomes from environmental samples using the binning of metagenomic data has expanded available reference genome catalogs, several microbial lineages remain underrepresented. Here, we present two reference-independent approaches for the identification, recovery, and refinement of hitherto undescribed population-level genomes. The first approach is aimed at genome recovery of varied taxa and involves multi-sample automated binning using CANOPY CLUSTERING complemented by visualization and human-augmented binning using VIZBIN post hoc. The second approach is particularly well-suited for the study of specific taxa and employs VIZBIN de novo. Using these approaches, we reconstructed a total of six population-level genomes of distinct and divergent representatives of the Alphaproteobacteria class, the Mollicutes class, the Clostridiales order, and the Melainabacteria class from human gastrointestinal tract-derived metagenomic data. Our results demonstrate that, while automated binning approaches provide great potential for large-scale studies of mixed microbial communities, these approaches should be complemented with informative visualizations because expert-driven inspection and refinements are critical for the recovery of high-quality population-level genomes.

Microorganisms in biological wastewater treatment plants require adaptive strategies to deal with rapidly fluctuating environmental conditions. At the population level, the filamentous bacterium Candidatus Microthrix parvicella (Ca. M. parvicella) has been found to fine-tune its gene expression for optimized substrate assimilation. Here we investigated in situ substrate assimilation by single cells of Ca. M. parvicella using nano-scale secondary-ion mass spectrometry (nanoSIMS). NanoSIMS imaging highlighted phenotypic heterogeneity among Ca. M. parvicella cells of the same filament, whereby (13)C-oleic acid and (13)C-glycerol-3-phosphate assimilation occurred in ≈21-55% of cells, despite non-assimilating cells being intact and alive. In response to alternating aerobic-anoxic regimes, (13)C-oleic acid assimilation occurred among subpopulations of Ca. M. parvicella cells (≈3-28% of cells). Furthermore, Ca. M. parvicella cells exhibited two temperature optima for (13)C-oleic acid assimilation and associated growth rates. These results suggest that phenotypic heterogeneity among Ca. M. parvicella cells allows the population to adapt rapidly to fluctuating environmental conditions facilitating its widespread occurrence in biological wastewater treatment plants.

Background: Mixed microbial communities underpin important biotechnological processes such as biological wastewater treatment (BWWT). A detailed knowledge of community structure and function relationships is essential for ultimately driving these systems towards desired outcomes, e.g., the enrichment in organisms capable of accumulating valuable resources during BWWT., Methods: A comparative integrated omic analysis including metagenomics, metatranscriptomics and metaproteomics was carried out to elucidate functional differences between seasonally distinct oleaginous mixed microbial communities (OMMCs) sampled from an anoxic BWWT tank. A computational framework for the reconstruction of community-wide metabolic networks from multi-omic data was developed. These provide an overview of the functional capabilities by incorporating gene copy, transcript and protein abundances. To identify functional genes, which have a disproportionately important role in community function, we define a high relative gene expression and a high betweenness centrality relative to node degree as gene-centric and network topological features, respectively., Results: Genes exhibiting high expression relative to gene copy abundance include genes involved in glycerolipid metabolism, particularly triacylglycerol lipase, encoded by known lipid accumulating populations, e.g., Candidatus Microthrix parvicella . Genes with a high relative gene expression and topologically important positions in the network include genes involved in nitrogen metabolism and fatty acid biosynthesis, encoded by Nitrosomonas spp. and Rhodococcus spp. Such genes may be regarded as 'keystone genes' as they are likely to be encoded by keystone species., Conclusion: The linking of key functionalities to community members through integrated omics opens up exciting possibilities for devising prediction and control strategies for microbial communities in the future., Competing Interests: The authors declare no conflict of interest.

Microbial communities are complex and dynamic systems that are primarily structured according to their members' ecological niches. To investigate how niche breadth (generalist versus specialist lifestyle strategies) relates to ecological success, we develop and apply an integrative workflow for the multi-omic analysis of oleaginous mixed microbial communities from a biological wastewater treatment plant. Time- and space-resolved coupled metabolomic and taxonomic analyses demonstrate that the community-wide lipid accumulation phenotype is associated with the dominance of the generalist bacterium Candidatus Microthrix spp. By integrating population-level genomic reconstructions (reflecting fundamental niches) with transcriptomic and proteomic data (realised niches), we identify finely tuned gene expression governing resource usage by Candidatus Microthrix parvicella over time. Moreover, our results indicate that the fluctuating environmental conditions constrain the accumulation of genetic variation in Candidatus Microthrix parvicella likely due to fitness trade-offs. Based on our observations, niche breadth has to be considered as an important factor for understanding the evolutionary processes governing (microbial) population sizes and structures in situ.

High-throughput sequencing of ribosomal RNA gene (rDNA) amplicons has opened up the door to large-scale comparative studies of microbial community structures. The short reads currently produced by massively parallel sequencing technologies make the choice of sequencing region crucial for accurate phylogenetic assignments. While for 16S rDNA, relevant regions have been well described, no truly systematic design of 18S rDNA primers aimed at resolving eukaryotic diversity has yet been reported. Here we used 31,862 18S rDNA sequences to design a set of broad-taxonomic range degenerate PCR primers. We simulated the phylogenetic information that each candidate primer pair would retrieve using paired- or single-end reads of various lengths, representing different sequencing technologies. Primer pairs targeting the V4 region performed best, allowing discrimination with paired-end reads as short as 150 bp (with 75% accuracy at genus level). The conditions for PCR amplification were optimised for one of these primer pairs and this was used to amplify 18S rDNA sequences from isolates as well as from a range of environmental samples which were then Illumina sequenced and analysed, revealing good concordance between expected and observed results. In summary, the reported primer sets will allow minimally biased assessment of eukaryotic diversity in different microbial ecosystems.

Objective: The aim of this study was to translate and adapt the Primary Care Assessment Tool to assess the perceptions of the quality of primary care among patients in China and to examine the psychometric properties of the adapted Primary Care Assessment Tool Chinese version (PCAT-C)., Design: A cross-sectional survey to assess the validity and reliability of PCAT-C using standard psychometric techniques., Setting: Outpatient departments of five state-level and provincial-level hospitals and four municipal-level hospitals as well as nine community health centers in Changsha, China., Participants: A total of 2532 patients visiting primary care providers., Results: The PCAT-C was acceptable to patients, as evidenced by low proportions of missing data and a full range of possible scores for all items. Two items were eliminated following principal component analysis and reliability testing. The principal component analysis extracted eight multiple-item scales and one single-item scale. Multiple-item scales had reasonable internal consistency and high item-scale correlations., Conclusions: This study represents the first attempt to construct an instrument for assessing patient reports on the quality of primary care, which is applicable to the Chinese context. Psychometric assessments indicated that the PCAT-C is a useful instrument for assessing the core attributes of primary care in China.

Objective: To describe current clinical quality among the nation's community health centers and to examine health center characteristics associated with performance excellence., Data Sources: National data from the 2009 Uniform Data System., Data Collection/extraction Methods: Health centers reviewed patient records and reported aggregate data to the Uniform Data System., Study Design: Six measures were examined: first-trimester prenatal care, childhood immunization completion, Pap tests, low birth weight, controlled hypertension, and controlled diabetes. The top 25 percent performing centers were compared with lower performing (bottom 75 percent) centers on these measures. Logistic regressions were utilized to assess the impact of patient, provider, and institutional characteristics on health center performance., Principal Findings: Clinical care and outcomes among health centers were generally comparable to national averages. For instance, 67 percent of pregnant patients received timely prenatal care (national = 68 percent), 69 percent of children achieved immunization completion (national = 67 percent), and 63 percent of hypertensive patients had blood pressure under control (national = 48 percent). Depending on the measure, centers with more uninsured patients were less likely to do well, while centers with more physicians and enabling service providers were more likely to do well., Conclusions: Health centers provide quality care at rates comparable to national averages. Performance may be improved by increasing insurance coverage among patients and increasing the ratios of physicians and enabling service providers to patients., (© Health Research and Educational Trust.)

Objectives: We examined primary care and public health activities among federally funded health centers, to better understand their successes, the barriers encountered, and the lessons learned., Methods: We used qualitative and quantitative methods to collect data from 9 health centers, stratified by administrative division, urban-rural location, and race/ethnicity of patients served. Descriptive data on patient and institutional characteristics came from the Uniform Data System, which collects data from all health centers annually. We administered questionnaires and conducted phone interviews with key informants., Results: Health centers performed well on primary care coordination and community orientation scales and reported conducting many essential public health activities. We identified specific needs for integrating primary care and public health: (1) more funding for collaborations and for addressing the social determinants of health, (2) strong leadership to champion collaborations, (3) trust building among partners, with shared missions and clear expectations of responsibilities, and (4) alignment and standardization of data collection, analysis, and exchange., Conclusions: Lessons learned from health centers should inform strategies to better integrate public health with primary care.

Objectives: Based on a recent patient survey from Taiwan, where there is universal health insurance coverage and unrestricted physician choice, this study examined the relationship between physician specialty and the quality of primary medical care experiences., Methods: We assessed ambulatory patients' experiences with medical care using the Primary Care Assessment Tool, representing 7 primary care domains: first contact (ie, accessibility and utilization); longitudinality (ie, ongoing care); coordination (ie, referrals and information systems); comprehensiveness (ie, services available and provided); family centeredness; community orientation; and cultural competence., Results: Having a primary care physician was significantly associated with patients reporting higher quality of primary care experiences. Specifically, relative to specialty care physicians, primary care physicians enhanced accessibility, achieved better community orientation and cultural competence, and provided more comprehensive services., Conclusions: In an area with universal health insurance and unrestricted physician choice, ambulatory patients of primary care physicians rated their medical care experiences as superior to those of patients of specialists. In addition to providing health insurance coverage, promoting primary care should be included as a health policy to improve patients' quality of ambulatory medical care experiences.

Objectives: In 2001, the Health Center Growth Initiative was launched to increase access to primary health-care services through the expansion of the health center program. We examined the impact this initiative had on the number and types of patients seen by health centers, as well as the health center characteristics significantly associated with service expansions., Methods: We conducted secondary and time-trend analyses of the Uniform Data System, an annual dataset submitted to the Bureau of Primary Health Care by all federally qualified health centers. We performed trend and multivariable analyses to examine the impact of the initiative on health center performance., Results: Health centers that received both new access points and expanded medical capacity funding saw the most rapid growth in patients. These centers experienced a 58% increase in total number of patients and a 60% increase in total number of encounters, compared with 10% and 8%, respectively, for centers receiving no funding at all., Conclusions: were unchanged even after controlling for other health center characteristics., Conclusions: Public funding is critical to sustaining and expanding health center services to the nation's vulnerable populations.

Low-income urban whites in the United States have largely gone unexamined in health disparities research. In this study, we explored cancer prevention behaviors in this population. We compared data on whites with low socioeconomic status (SES) from the 2003 Exploring Health Disparities in Integrated Communities Study in Southwest Baltimore, Maryland (EHDIC-SWB) with nationally representative data for low SES white respondents from the 2003 National Health Interview Survey (NHIS). Rates for health behaviors and health indicators for whites from the EHDIC-SWB study as compared to NHIS prevalence estimates were as follows: current cigarette smoking, 59% (31% nationally); current regular drinking, 5% (5% nationally); overweight, 26% (32% nationally); obesity, 30% (22% nationally); mammography in the past 2 years, 50% (57% nationally); Pap smear in the past 2 years, 64% (68% nationally); screening for colon cancer in the past 2 years, 41% (30% nationally); and fair or poor self-reported health, 37% (22% nationally). Several cancer prevention behaviors and health indicators for white EHDIC-SWB respondents were far from the Healthy People 2010 objectives. This study provides rare estimates of cancer-related health and health care measures in an understudied population in the United States. Findings illustrate the need for further examination of health behaviors in low SES white urban populations who may share health risks with their poor minority urban counterparts.

Synthetic peptides based on amino-acid residues 27-38 of human serum amyloid P component represent a novel type of heparin binders as they do not contain clusters of basic amino acids or other known features associated with protein or peptide heparin binding. Here, we characterize the binding using capillary electrophoresis (CE), surface plasmon resonance (SPR), and isothermal titration calorimetry (ITC). By CE, heparin-binding activity was readily apparent for both a regular peptide and a slightly N-terminally modified form, while a sequence-scrambled peptide had no measurable binding. Dissociation constants in the 1-15 microm range were estimated, but only a minor part of the binding isotherm was covered by the experiments. SPR measurements using immobilized peptides verified heparin binding, the range of the binding constants, and the reduced binding of the sequence-scrambled peptide. Structurally defined heparin oligosaccharides were used to establish that while the tetrasaccharide is too small to exhibit strong binding, little difference in binding strength is observed between hexa- and tetradeca-saccharides. These experiments also confirmed the almost complete lack of activity of the sequence-scrambled peptide. The amino-acid sequence-dependent binding and the importance of a disulfide bond in the peptide were verified by ITC, but the experimental conditions had to be modified because of peptide precipitation and ITC yielded significantly weaker binding constants than the other methods. While the precise function of the peptide in the intact protein remains unclear, the results confirm the specificity of the glycosaminoglycan interaction with regard to peptide sequence by applying two additional biophysical techniques and showing that the N-terminal part of the peptide may be modified without changing the heparin binding capabilities.

The prosthetic heme group in the CYP4A family of cytochrome P450 enzymes is covalently attached to an I-helix glutamic acid residue. This glutamic acid is conserved in the CYP4 family but is absent in other P450 families. As shown here, the glutamic acid is linked, presumably via an ester bond, to a hydroxyl group on the heme 5-methyl group. Mutation of the glutamic acid to an alanine in CYP4A1, CYP4A3, and CYP4A11 suppresses covalent heme binding. In wild-type CYP4A3 68% of the heme is covalently bound to the heterologously expressed protein, but in the CYP4A3/E318D mutant, 47% of the heme is unchanged, 47% is present as noncovalently bound 5-hydroxymethylheme, and only 6% is covalently bound to the protein. In the CYP4A3/E318Q mutant, the majority of the heme is unaltered, and <2% is covalently linked. The proportion of covalently bound heme in the recombinant CYP4A proteins increases with time under turnover conditions. The catalytic activity is sensitive in some, but not all, CYP4A enzymes to the extent of covalent heme binding. Mutations of Glu(318) in CYP4A3 decrease the apparent k(cat) values for lauric acid hydroxylation. The key conclusions are that (a) covalent heme binding occurs via an ester bond to the heme 5-methyl group, (b) covalent binding of the heme is mediated by an autocatalytic process, and (c) fatty acid oxidation is sensitive in some CYP4A enzymes to the presence or absence of the heme covalent link.