Immunization with lytic polysaccharide monooxygenase CbpD induces protective immunity against Pseudomonas aeruginosa pneumonia.

Pseudomonas aeruginosa (PA) CbpD belongs to the lytic polysaccharide monooxygenases (LPMOs), a family of enzymes that cleave chitin or related polysaccharides. Here, we demonstrate a virulence role of CbpD in PA pneumonia linked to impairment of host complement function and opsonophagocytic clearance. Following intratracheal challenge, a PA ΔCbpD mutant was more easily cleared and produced less mortality than the wild-type parent strain. The x-ray crystal structure of the CbpD LPMO domain was solved to subatomic resolution (0.75Å) and its two additional domains modeled by small-angle X-ray scattering and Alphafold2 machine-learning algorithms, allowing structure-based immune epitope mapping. Immunization of naive mice with recombinant CbpD generated high IgG antibody titers that promoted human neutrophil opsonophagocytic killing, neutralized enzymatic activity, and protected against lethal PA pneumonia and sepsis. IgG antibodies generated against full-length CbpD or its noncatalytic M2+CBM73 domains were opsonic and protective, even in previously PA-exposed mice, while antibodies targeting the AA10 domain were not. Preexisting antibodies in PA-colonized cystic fibrosis patients primarily target the CbpD AA10 catalytic domain. Further exploration of LPMO family proteins, present across many clinically important and antibiotic-resistant human pathogens, may yield novel and effective vaccine antigens.

Early Evidence of Chronic Obstructive Pulmonary Disease Obscured by Race-Specific Prediction Equations.

Rationale: The identification of early chronic obstructive pulmonary disease (COPD) is essential to appropriately counsel patients regarding smoking cessation, provide symptomatic treatment, and eventually develop disease-modifying treatments. Disease severity in COPD is defined using race-specific spirometry equations. These may disadvantage non-White individuals in diagnosis and care. Objectives: Determine the impact of race-specific equations on African American (AA) versus non-Hispanic White individuals. Methods: Cross-sectional analyses of the COPDGene (Genetic Epidemiology of Chronic Obstructive Pulmonary Disease) cohort were conducted, comparing non-Hispanic White (n = 6,766) and AA (n = 3,366) participants for COPD manifestations. Measurements and Main Results: Spirometric classifications using race-specific, multiethnic, and "race-reversed" prediction equations (NHANES [National Health and Nutrition Examination Survey] and Global Lung Function Initiative "Other" and "Global") were compared, as were respiratory symptoms, 6-minute-walk distance, computed tomography imaging, respiratory exacerbations, and St. George's Respiratory Questionnaire. Application of different prediction equations to the cohort resulted in different classifications by stage, with NHANES and Global Lung Function Initiative race-specific equations being minimally different, but race-reversed equations moving AA participants to more severe stages and especially between the Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage 0 and preserved ratio impaired spirometry groups. Classification using the established NHANES race-specific equations demonstrated that for each of GOLD stages 1-4, AA participants were younger, had fewer pack-years and more current smoking, but had more exacerbations, shorter 6-minute-walk distance, greater dyspnea, and worse BODE (body mass index, airway obstruction, dyspnea, and exercise capacity) scores and St. George's Respiratory Questionnaire scores. Differences were greatest in GOLD stages 1 and 2. Race-reversed equations reclassified 774 AA participants (43%) from GOLD stage 0 to preserved ratio impaired spirometry. Conclusions: Race-specific equations underestimated disease severity among AA participants. These effects were particularly evident in early disease and may result in late detection of COPD.

Bone Marrow Transplantation Rescues Monocyte Recruitment Defect and Improves Cystic Fibrosis in Mice.

Cystic fibrosis (CF) is an inherited life-threatening disease accompanied by repeated lung infections and multiorgan inflammation that affects tens of thousands of people worldwide. The causative gene, cystic fibrosis transmembrane conductance regulator (CFTR), is mutated in CF patients. CFTR functions in epithelial cells have traditionally been thought to cause the disease symptoms. Recent work has shown an additional defect: monocytes from CF patients show a deficiency in integrin activation and adhesion. Because monocytes play critical roles in controlling infections, defective monocyte function may contribute to CF progression. In this study, we demonstrate that monocytes from CFTRΔF508 mice (CF mice) show defective adhesion under flow. Transplanting CF mice with wild-type (WT) bone marrow after sublethal irradiation replaced most (60-80%) CF monocytes with WT monocytes, significantly improved survival, and reduced inflammation. WT/CF mixed bone marrow chimeras directly demonstrated defective CF monocyte recruitment to the bronchoalveolar lavage and the intestinal lamina propria in vivo. WT mice reconstituted with CF bone marrow also show lethality, suggesting that the CF defect in monocytes is not only necessary but also sufficient to cause disease. We also show that monocyte-specific knockout of CFTR retards weight gains and exacerbates dextran sulfate sodium-induced colitis. Our findings show that providing WT monocytes by bone marrow transfer rescues mortality in CF mice, suggesting that similar approaches may mitigate disease in CF patients.

Use of the Spirometric "Fixed-Ratio" Underdiagnoses COPD in African-Americans in a Longitudinal Cohort Study.

BACKGROUND: COPD diagnosis is tightly linked to the fixed-ratio spirometry criteria of FEV1/FVC < 0.7. African-Americans are less often diagnosed with COPD. OBJECTIVE: Compare COPD diagnosis by fixed-ratio with findings and outcomes by race. DESIGN: Genetic Epidemiology of COPD (COPDGene) (2007-present), cross-sectional comparing non-Hispanic white (NHW) and African-American (AA) participants for COPD diagnosis, manifestations, and outcomes. SETTING: Multicenter, longitudinal US cohort study. PARTICIPANTS: Current or former smokers with ≥ 10-pack-year smoking history enrolled at 21 clinical centers including over-sampling of participants with known COPD and AA. Exclusions were pre-existing non-COPD lung disease, except for a history of asthma. MEASUREMENTS: Subject diagnosis by conventional criteria. Mortality, imaging, respiratory symptoms, function, and socioeconomic characteristics, including area deprivation index (ADI). Matched analysis (age, sex, and smoking status) of AA vs. NHW within participants without diagnosed COPD (GOLD 0; FEV1 ≥ 80% predicted and FEV1/FVC ≥ 0.7). RESULTS: Using the fixed ratio, 70% of AA (n = 3366) were classified as non-COPD, versus 49% of NHW (n = 6766). AA smokers were younger (55 vs. 62 years), more often current smoking (80% vs. 39%), with fewer pack-years but similar 12-year mortality. Density distribution plots for FEV1 and FVC raw spirometry values showed disproportionate reductions in FVC relative to FEV1 in AA that systematically led to higher ratios. The matched analysis demonstrated GOLD 0 AA had greater symptoms, worse DLCO, spirometry, BODE scores (1.03 vs 0.54, p < 0.0001), and greater deprivation than NHW. LIMITATIONS: Lack of an alternative diagnostic metric for comparison. CONCLUSIONS: The fixed-ratio spirometric criteria for COPD underdiagnosed potential COPD in AA participants when compared to broader diagnostic criteria. Disproportionate reductions in FVC relative to FEV1 leading to higher FEV1/FVC were identified in these participants and associated with deprivation. Broader diagnostic criteria for COPD are needed to identify the disease across all populations.

Impacts of innovation in dental care delivery and payment in Medicaid managed care for children and adolescents.

BACKGROUND: We evaluated a 14-county quality improvement program of care delivery and payment of a dental care organization for child and adolescent managed care Medicaid beneficiaries after 2 years of implementation. METHODS: Counties were randomly assigned to either the intervention (PREDICT) or control group. Using Medicaid administrative data, difference-in-difference regression models were used to estimate PREDICT intervention effects (formally, "average marginal effects") on dental care utilization and costs to Medicaid, controlling for patient and county characteristics. RESULTS: Average marginal effects of PREDICT on expected use and expected cost of services per patient (child or adolescent) per quarter were small and insignificant for most service categories. There were statistically significant effects of PREDICT (p < .05), though still small, for certain types of service: (1) Expected number of diagnostic services per patient-quarter increased by .009 units; (2) Expected number of sealants per patient-quarter increased by .003 units, and expected cost by $0.06; (3) Total expected cost per patient-quarter for all services increased by $0.64. These consistent positive effects of PREDICT on diagnostic and certain preventive services (i.e., sealants) were not accompanied by increases in more costly service types (i.e., restorations) or extractions. CONCLUSION: The major hypothesis that primary dental care (selected preventive services and diagnostic services in general) would increase significantly over time in PREDICT counties relative to controls was supported. There were small but statistically significant, increases in differential use of diagnostic services and sealants. Total cost per beneficiary rose modestly, but restorative and dental costs did not. The findings suggest favorable developments within PREDICT counties in enhanced preventive and diagnostic procedures, while holding the line on expensive restorative and extraction procedures.

Plasmonic Sensing Studies of a Gas-Phase Cystic Fibrosis Marker in Moisture Laden Air.

A plasmonic sensing platform was developed as a noninvasive method to monitor gas-phase biomarkers related to cystic fibrosis (CF). The nanohole array (NHA) sensing platform is based on localized surface plasmon resonance (LSPR) and offers a rapid data acquisition capability. Among the numerous gas-phase biomarkers that can be used to assess the lung health of CF patients, acetaldehyde was selected for this investigation. Previous research with diverse types of sensing platforms, with materials ranging from metal oxides to 2-D materials, detected gas-phase acetaldehyde with the lowest detection limit at the µmol/mol (parts-per-million (ppm)) level. In contrast, this work presents a plasmonic sensing platform that can approach the nmol/mol (parts-per-billion (ppb)) level, which covers the required concentration range needed to monitor the status of lung infection and find pulmonary exacerbations. During the experimental measurements made by a spectrometer and by a smartphone, the sensing examination was initially performed in a dry air background and then with high relative humidity (RH) as an interferent, which is relevant to exhaled breath. At a room temperature of 23.1 °C, the lowest detection limit for the investigated plasmonic sensing platform under dry air and 72% RH conditions are 250 nmol/mol (ppb) and 1000 nmol/mol (ppb), respectively.

Multi-Omics Study of Keystone Species in a Cystic Fibrosis Microbiome.

Ecological networking and in vitro studies predict that anaerobic, mucus-degrading bacteria are keystone species in cystic fibrosis (CF) microbiomes. The metabolic byproducts from these bacteria facilitate the colonization and growth of CF pathogens like Pseudomonas aeruginosa. Here, a multi-omics study informed the control of putative anaerobic keystone species during a transition in antibiotic therapy of a CF patient. A quantitative metagenomics approach combining sequence data with epifluorescence microscopy showed that during periods of rapid lung function loss, the patient's lung microbiome was dominated by the anaerobic, mucus-degrading bacteria belonging to Streptococcus, Veillonella, and Prevotella genera. Untargeted metabolomics and community cultures identified high rates of fermentation in these sputa, with the accumulation of lactic acid, citric acid, and acetic acid. P. aeruginosa utilized these fermentation products for growth, as indicated by quantitative transcriptomics data. Transcription levels of P. aeruginosa genes for the utilization of fermentation products were proportional to the abundance of anaerobic bacteria. Clindamycin therapy targeting Gram-positive anaerobes rapidly suppressed anaerobic bacteria and the accumulation of fermentation products. Clindamycin also lowered the abundance and transcription of P. aeruginosa, even though this patient's strain was resistant to this antibiotic. The treatment stabilized the patient's lung function and improved respiratory health for two months, lengthening by a factor of four the between-hospitalization time for this patient. Killing anaerobes indirectly limited the growth of P. aeruginosa by disrupting the cross-feeding of fermentation products. This case study supports the hypothesis that facultative anaerobes operated as keystone species in this CF microbiome. Personalized multi-omics may become a viable approach for routine clinical diagnostics in the future, providing critical information to inform treatment decisions.

Mixed-Methods Evaluation of the Washington State Practice Transformation Support Hub.

PURPOSE: Practice transformation initiatives have the potential to promote collaborations between public health, primary care, and behavioral health, but limited empirical evidence is available on how these programs affect participating clinical practices. OBJECTIVE: To report the findings from a mixed-methods program evaluation of the Washington Practice Transformation Support Hub (Hub), a publicly funded, multicomponent practice transformation initiative in Washington State. DESIGN: We used quantitative and qualitative methods to evaluate the impact of Hub activities on participating primary care and behavioral health practices. Pre- and posttest survey data were combined with administrative program data to understand the effect of program components. Qualitative interviews contextualized findings. SETTING: Urban and rural primary care and behavioral health practices in Washington State. PARTICIPANTS: One hundred seventy-five practices that were recruited to receive Hub coaching and facilitation from 8 coaches; of these, 13 practices and all coaches participated in key informant interviews. INTERVENTION: Practice coaching and facilitation supported by an online resource portal, from January 2017 through January 2019. MAIN OUTCOME MEASURES: Self-reported progress in specific activities in 3 practice-level domains: bidirectional integration of physical and behavioral health care (care integration); alignment with community-based services for whole-person care (clinical-community linkages); and value-based payment. RESULTS: Participation in Hub activities was associated with improvements in care integration and clinical-community linkages but not with progress toward value-based payment. Qualitative results indicated that practice progress was influenced by communication with practices, the culture of the practice, resource constraints (particularly in rural areas), and perceptions about sustainability. CONCLUSIONS: This statewide practice transformation initiative was successful in strengthening primary care and behavioral health integration and clinical-community linkages among participating practices but not value-based payment. Future practice transformation efforts may benefit from addressing barriers posed by communication, limited application of value-based payment, culture change, competing priorities, and resource limitations, particularly for rural communities.

Smartphone-Based pH Sensor for Home Monitoring of Pulmonary Exacerbations in Cystic Fibrosis.

Currently, Cystic Fibrosis (CF) patients lack the ability to track their lung health at home, relying instead on doctor checkups leading to delayed treatment and lung damage. By leveraging the ubiquity of the smartphone to lower costs and increase portability, a smartphone-based peripheral pH measurement device was designed to attach directly to the headphone port to harvest power and communicate with a smartphone application. This platform was tested using prepared pH buffers and sputum samples from CF patients. The system matches within ~0.03 pH of a benchtop pH meter while fully powering itself and communicating with a Samsung Galaxy S3 smartphone paired with either a glass or Iridium Oxide (IrOx) electrode. The IrOx electrodes were found to have 25% higher sensitivity than the glass probes at the expense of larger drift and matrix sensitivity that can be addressed with proper calibration. The smartphone-based platform has been demonstrated as a portable replacement for laboratory pH meters, and supports both highly robust glass probes and the sensitive and miniature IrOx electrodes with calibration. This tool can enable more frequent pH sputum tracking for CF patients to help detect the onset of pulmonary exacerbation to provide timely and appropriate treatment before serious damage occurs.

Provider perceptions of the electronic health record incentive programs: a survey of eligible professionals who have and have not attested to meaningful use.

BACKGROUND: The HITECH Act of 2009 enabled the Centers for Medicare & Medicaid Services (CMS) to provide financial incentives to health care providers who demonstrate "meaningful use" (MU) of their electronic health records (EHRs). Despite stakeholder involvement in the rule-making phase, formal input about the MU program from a cross section of providers has not been reported since incentive payments began. OBJECTIVE: To examine the perspectives and experiences of a random sample of health care professionals eligible for financial incentives (eligible professionals or EPs) for demonstrating meaningful use of their EHRs. It was hypothesized that EPs actively participating in the MU program would generally view the purported benefits of MU more positively than EPs not yet participating in the incentive program. DESIGN: Survey data were collected by mail from a random sample of EPs in Washington State and Idaho. Two follow-up mailings were made to non-respondents. PARTICIPANTS: The sample included EPs who had registered for incentive payments or attested to MU (MU-Active) and EPs not yet participating in the incentive program (MU-Inactive). MAIN MEASURES: The survey assessed perceptions of general realities and influences of MU on health care; views on the influence of MU on clinics; and personal views about MU. EP opinions were assessed with close- and open-ended items. KEY RESULTS: Close-ended responses indicated that MU-Active providers were generally more positive about the program than MU-Inactive providers. However, the majority of respondents in both groups felt that MU would not reduce care disparities or improve the accuracy of patient information. The additional workload on EPs and their staff was viewed as too great a burden on productivity relative to the level of reimbursement for achieving MU goals. The majority of open-ended responses in each group reinforced the general perception that the MU program diverted attention from treating patients by imposing greater reporting requirements. CONCLUSIONS: Survey results indicate the need by CMS to step up engagement with EPs in future planning for the MU program, while also providing support for achieving MU standards.

Mass spectral similarity for untargeted metabolomics data analysis of complex mixtures.

While in nucleotide sequencing, the analysis of DNA from complex mixtures of organisms is common, this is not yet true for mass spectrometric data analysis of complex mixtures. The comparative analyses of mass spectrometry data of microbial communities at the molecular level is difficult to perform, especially in the context of a host. The challenge does not lie in generating the mass spectrometry data, rather much of the difficulty falls in the realm of how to derive relevant information from this data. The informatics based techniques to visualize and organize datasets are well established for metagenome sequencing; however, due to the scarcity of informatics strategies in mass spectrometry, it is currently difficult to cross correlate two very different mass spectrometry data sets from microbial communities and their hosts. We highlight that molecular networking can be used as an organizational tool of tandem mass spectrometry data, automated database search for rapid identification of metabolites, and as a workflow to manage and compare mass spectrometry data from complex mixtures of organisms. To demonstrate this platform, we show data analysis from hard corals and a human lung associated with cystic fibrosis.

The upper respiratory tract as a microbial source for pulmonary infections in cystic fibrosis. Parallels from island biogeography.

A continuously mixed series of microbial communities inhabits various points of the respiratory tract, with community composition determined by distance from colonization sources, colonization rates, and extinction rates. Ecology and evolution theory developed in the context of biogeography is relevant to clinical microbiology and could reframe the interpretation of recent studies comparing communities from lung explant samples, sputum samples, and oropharyngeal swabs. We propose an island biogeography model of the microbial communities inhabiting different niches in human airways. Island biogeography as applied to communities separated by time and space is a useful parallel for exploring microbial colonization of healthy and diseased lungs, with the potential to inform our understanding of microbial community dynamics and the relevance of microbes detected in different sample types. In this perspective, we focus on the intermixed microbial communities inhabiting different regions of the airways of patients with cystic fibrosis.

Clinical insights from metagenomic analysis of sputum samples from patients with cystic fibrosis.

As DNA sequencing becomes faster and cheaper, genomics-based approaches are being explored for their use in personalized diagnoses and treatments. Here, we provide a proof of principle for disease monitoring using personal metagenomic sequencing and traditional clinical microbiology by focusing on three adults with cystic fibrosis (CF). The CF lung is a dynamic environment that hosts a complex ecosystem composed of bacteria, viruses, and fungi that can vary in space and time. Not surprisingly, the microbiome data from the induced sputum samples we collected revealed a significant amount of species diversity not seen in routine clinical laboratory cultures. The relative abundances of several species changed as clinical treatment was altered, enabling the identification of the climax and attack communities that were proposed in an earlier work. All patient microbiomes encoded a diversity of mechanisms to resist antibiotics, consistent with the characteristics of multidrug-resistant microbial communities that are commonly observed in CF patients. The metabolic potentials of these communities differed by the health status and recovery route of each patient. Thus, this pilot study provides an example of how metagenomic data might be used with clinical assessments for the development of treatments tailored to individual patients.

Measuring primary care organizational capacity for diabetes care coordination: the Diabetes Care Coordination Readiness Assessment.

BACKGROUND: Not all primary care clinics are prepared to implement care coordination services for chronic conditions, such as diabetes. Understanding true capacity to coordinate care is an important first-step toward establishing effective and efficient care coordination. Yet, we could identify no diabetes-specific instruments to systematically assess readiness and/or status of primary care clinics to engage in diabetes care coordination. OBJECTIVE: This report describes the development and initial validation of the Diabetes Care Coordination Readiness Assessment (DCCRA), which is intended to measure primary care clinic readiness to coordinate care for adult patients with diabetes. DESIGN: The instrument was developed through iterative item generation within a framework of five domains of care coordination: Organizational Capacity, Care Coordination, Clinical Management, Quality Improvement, and Technical Infrastructure. PARTICIPANTS: Validation data was collected on 39 primary care clinics. MAIN MEASURES: Content validity, inter-rater reliability, internal consistency, and construct validity of the 49-item instrument were assessed. KEY RESULTS: Inter-rater agreement indices per item ranged from 0.50 to 1.0. Cronbach's alpha of the entire instrument was 0.964, and for the five domain scales ranged from 0.688 to 0.961. Clinics with existing care coordinators were rated as more ready to support care coordination than clinics without care coordinators for the entire DCCRA and for each domain, supporting construct validity. CONCLUSIONS: As providers increasingly attempt to adopt patient-centered approaches, introduction of the DCCRA is timely and appropriate for assisting clinics with identifying gaps in provision of care coordination services. The DCCRA's strengths include promising psychometric properties. A valid measure of diabetes care coordination readiness should be useful in diabetes program evaluation, assistance with quality improvement initiatives, and measurement of patient-centered care in research.

Emerging lessons from regional and state innovation in value-based payment reform: balancing collaboration and disruptive innovation.

CONTEXT: In recent decades, practitioners and policymakers have turned to value-based payment initiatives to help contain spending on health care and to improve the quality of care. The Robert Wood Johnson Foundation funded 7 grantees across the country to design and implement value-based, multistakeholder payment reform projects in 6 states and 3 regions of the United States. METHODS: As the external evaluator of these projects, we reviewed documents, conducted Internet searches, interviewed key stakeholders, cross-validated factual and narrative interpretation, and performed qualitative analyses to derive cross-site themes and implications for policy and practice. FINDINGS: The nature of payment reform and its momentum closely reflects the environmental context of each project. Federal legislation such as the Patient Protection and Affordable Care Act and federal and state support for the development of the patient-centered medical home and accountable care organizations encourage value-based payment innovation, as do local market conditions for payers and providers that combine a history of collaboration with independent innovation and experimentation by individual organizations. Multistakeholder coalitions offer a useful facilitating structure for galvanizing payment reform. But to achieve the objectives of reduced cost and improved quality, multistakeholder payment innovation must overcome such barriers as incompatible information systems, the technical difficulties and transaction costs of altering existing billing and payment systems, competing stakeholder priorities, insufficient scale to bear population health risk, providers' limited experience with risk-bearing payment models, and the failure to align care delivery models with the form of payment. CONCLUSIONS: From the evidence adduced in this article, multistakeholder, value-based payment reform requires a trusted, widely respected "honest broker" that can convene and maintain the ongoing commitment of health plans, providers, and purchasers. Change management is complex and challenging, and coalition governance requires flexibility and stable leadership, as market conditions and stakeholder engagement and priorities shift over time. Another significant facilitator of value-based payment reform is outside investment that enables increased investment in human resources, information infrastructure, and care management by provider organizations and their collaborators. Supportive community and social service networks that enhance population health management also are important enablers of value-based payment reform. External pressure from public and private payers is fueling a "burning bridge" between the past of fee-for-service payment models and the future of payments based on value. Robust competition in local health plan and provider markets, coupled with an appropriate mix of multistakeholder governance, pressure from organized purchasers, and regulatory oversight, has the potential to spur value-based payment innovation that combines elements of "reformed" fee-for-service with bundled payments and global payments.

A GMR enzymatic assay for quantifying nuclease and peptidase activity.

Hydrolytic enzymes play crucial roles in cellular processes, and dysregulation of their activities is implicated in various physiological and pathological conditions. These enzymes cleave substrates such as peptide bonds, phosphodiester bonds, glycosidic bonds, and other esters. Detecting aberrant hydrolase activity is vital for understanding disease mechanisms and developing targeted therapeutic interventions. This study introduces a novel approach to measuring hydrolase activity using giant magnetoresistive (GMR) spin valve sensors. These sensors change resistance in response to magnetic fields, and here, they are functionalized with specific substrates for hydrolases conjugated to magnetic nanoparticles (MNPs). When a hydrolase cleaves its substrate, the tethered magnetic nanoparticle detaches, causing a measurable shift in the sensor's resistance. This design translates hydrolase activity into a real-time, activity-dependent signal. The assay is simple, rapid, and requires no washing steps, making it ideal for point-of-care settings. Unlike fluorescent methods, it avoids issues like autofluorescence and photobleaching, broadening its applicability to diverse biofluids. Furthermore, the sensor array contains 80 individually addressable sensors, allowing for the simultaneous measurement of multiple hydrolases in a single reaction. The versatility of this method is demonstrated with substrates for nucleases, Bcu I and DNase I, and the peptidase, human neutrophil elastase. To demonstrate a clinical application, we show that neutrophil elastase in sputum from cystic fibrosis patients hydrolyze the peptide-GMR substrate, and the cleavage rate strongly correlates with a traditional fluorogenic substrate. This innovative assay addresses challenges associated with traditional enzyme measurement techniques, providing a promising tool for real-time quantification of hydrolase activities in diverse biological contexts.

Cystic fibrosis therapy: a community ecology perspective.

Current therapy for cystic fibrosis (CF) focuses on minimizing the microbial community and the host's immune response through the aggressive use of airway clearance techniques, broad-spectrum antibiotics, and treatments that break down the pervasive endobronchial biofilm. Antibiotic selection is typically based on the susceptibility of individual microbial strains to specific antibiotics in vitro. Often this approach cannot accurately predict medical outcomes because of factors both technical and biological. Recent culture-independent assessments of the airway microbial and viral communities demonstrated that the CF airway infection is considerably more complex and dynamic than previously appreciated. Understanding the ecological and evolutionary pressures that shape these communities is critically important for the optimal use of current therapies (in both the choice of therapy and timing of administration) and the development of newer strategies. The climax-attack model (CAM) presented here, grounded in basic ecological principles, postulates the existence of two major functional communities. The attack community consists of transient viral and microbial populations that induce strong innate immune responses. The resultant intense immune response creates microenvironments that facilitate the establishment of a climax community that is slower-growing and inherently resistant to antibiotic therapy. Newer methodologies, including sequence-based metagenomic analysis, can track not only the taxonomic composition but also the metabolic capabilities of these changing viral and microbial communities over time. Collecting this information for CF airways will enable the mathematical modeling of microbial community dynamics during disease progression. The resultant understanding of airway communities and their effects on lung physiology will facilitate the optimization of CF therapies.

Toward implementation of quorum sensing autoinducers as biomarkers for infectious disease states.

The opportunistic bacterial pathogen Pseudomonas aeruginosa causes chronic lung infections in cystic fibrosis (CF) patients. Importantly, virulence factor expression and biofilm formation in P. aeruginosa is coordinated by quorum sensing (QS) and one of the key QS signaling molecules is 3-oxo-C12-HSL. Remarkably, a tetramic acid, (C12-TA), with antibacterial properties is formed spontaneously from 3-oxo-C12-HSL under physiological conditions. Seeking to better understand this relationship, we sought to investigate whether 3-oxo-C12-HSL and C12-TA may be contributing factors to the overall pathogenicity of P. aeruginosa in CF individuals and if their detection and quantitation in sputum samples might be used as an indicator to assess disease states and monitor therapy success in CF patients. To this end, 3-oxo-C12-HSL and C12-TA concentrations were initially analyzed in P. aeruginosa flow cell biofilms using liquid chromatography coupled with mass spectrometry (LC-MS). A liquid chromatography tandem mass spectrometry (LC-MS/MS)-based method was then developed and validated for their detection and quantification in the sputa of CF patients. To the best of our knowledge, this is the first report to show the presence of both the quorum sensing molecule (3-oxo-C12-HSL) and its rearranged product (C12-TA) in human clinical samples such as sputum. A total of 47 sputum samples from 20 CF and 2 non-CF individuals were analyzed. 3-Oxo-C12-HSL was detected and quantified in 45 samples with concentrations ranging from 20 to >1000 nM; C12-TA was found in 14 samples (13-900 nM). On the basis of our findings, quorum sensing autoinducers merit further investigation as biomarkers for infectious disease states.

ß-adrenergic sweat secretion as a diagnostic test for cystic fibrosis.

RATIONALE: ß-Adrenergically induced sweat secretion offers an expedient method to assess native cystic fibrosis transmembrane conductance regulator (CFTR) secretory function in vivo. OBJECTIVES: To evaluate the sensitivity, specificity, and reliability of a test based on the activity and secretory function of CFTR in the sweat gland. METHODS: Primary and validation trials with prospectively ascertained healthy control subjects, obligate heterozygotes, and patients with a CFTR-related disorder and CF (pancreatic sufficient and insufficient). MEASUREMENTS AND MAIN RESULTS: Diagnostic accuracy and reliability of ß-adrenergic sweat secretory rates using an evaporimeter was assessed and compared with sweat chloride concentrations. The cholinergically stimulated mean sweat rate did not differ among groups. The mean maximal ß-adrenergically stimulated sweat rate in heterozygotes was about half the rate of healthy control subjects, and completely absent in pancreatic-insufficient patients with CF and pancreatic-sufficient patients with CF (P < 0.0001). Subjects with a CFTR-related disorder showed reduced or absent ß-adrenergic sweat secretion. The ß-adrenergic secretory response demonstrated high diagnostic accuracy (area under a characteristic receiver-operator curve = 0.99; 95% confidence interval, 0.97-1.00) and reliability (intraclass correlation, 0.90; 95% confidence interval, 0.81-0.95). The diagnostic cutoff level for CF, derived from the primary trial, correctly identified all control subjects, heterozygotes, and patients with CF in the validation cohort, whereas concurrent sweat chloride measurements misclassified one heterozygote and five subjects with CF. The cholinergic and ß-adrenergic sweat secretion rates were lower in women compared with men (P < 0.001). CONCLUSIONS: ß-Adrenergic sweat secretion rate determined by evaporimetry is an accurate and reliable technique to assess different levels of CFTR function and to identify patients with CF.

Effects of individual physician-level and practice-level financial incentives on hypertension care: a randomized trial.

IMPORTANCE: Pay for performance is intended to align incentives to promote high-quality care, but results have been contradictory. OBJECTIVE: To test the effect of explicit financial incentives to reward guideline-recommended hypertension care. DESIGN, SETTING, AND PARTICIPANTS: Cluster randomized trial of 12 Veterans Affairs outpatient clinics with 5 performance periods and a 12-month washout that enrolled 83 primary care physicians and 42 nonphysician personnel (eg, nurses, pharmacists). INTERVENTIONS: Physician-level (individual) incentives, practice-level incentives, both, or none. Intervention participants received up to 5 payments every 4 months; all participants could access feedback reports. MAIN OUTCOMES AND MEASURES: Among a random sample, number of patients achieving guideline-recommended blood pressure thresholds or receiving an appropriate response to uncontrolled blood pressure, number of patients prescribed guideline-recommended medications, and number who developed hypotension. RESULTS: Mean (SD) total payments over the study were $4270 ($459), $2672 ($153), and $1648 ($248) for the combined, individual, and practice-level interventions, respectively. The unadjusted baseline and final percentages and the adjusted absolute change over the study in patients meeting the combined blood pressure/appropriate response measure were 75% to 84% and 8.84% (95% CI, 4.20% to 11.80%) for the individual group, 80% to 85% and 3.70% (95% CI, 0.24% to 7.68%) for the practice-level group, 79% to 88% and 5.54% (95% CI, 1.92% to 9.52%) for the combined group, and 86% to 86% and 0.47% (95% CI, -3.12% to 4.04%) for the control group. The adjusted absolute estimated difference in the change between the proportion of patients with blood pressure control/appropriate response for individual incentive and control groups was 8.36% (95% CI, 2.40% to 13.00%; P=.005). The other incentive groups did not show a significant change compared with controls for this outcome. For medications, the unadjusted baseline and final percentages and the adjusted absolute change were 61% to 73% and 9.07% (95% CI, 4.52% to 13.44%), 56% to 65% and 4.98% (95% CI, 0.64% to 10.08%), 65% to 80% and 7.26% (95% CI, 2.92% to 12.48%), and 63% to 72% and 4.35% (95% CI, -0.28% to 9.28%), respectively. These changes in the use of guideline-recommended medications were not significant in any of the incentive groups compared with controls, nor was the incidence of hypotension. The effect of the incentive was not sustained after a washout. CONCLUSIONS AND RELEVANCE: Individual financial incentives, but not practice-level or combined incentives, resulted in greater blood pressure control or appropriate response to uncontrolled blood pressure; none of the incentives resulted in greater use of guideline-recommended medications or increased incidence of hypotension compared with controls. Further research is needed on the factors that contributed to these findings. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00302718.