Rapid phenotypic and genotypic change in a laboratory schistosome population.

Background: Genomic analysis has revealed extensive contamination among laboratory-maintained microbes including malaria parasites, Mycobacterium tuberculosis and Salmonella spp. Here, we provide direct evidence for recent contamination of a laboratory schistosome parasite population, and we investigate its genomic consequences. The Brazilian Schistosoma mansoni population SmBRE has several distinctive phenotypes, showing poor infectivity, reduced sporocysts number, low levels of cercarial shedding and low virulence in the intermediate snail host, and low worm burden and low fecundity in the vertebrate rodent host. In 2021 we observed a rapid change in SmBRE parasite phenotypes, with a ∼10x increase in cercarial production and ∼4x increase in worm burden. Methods: To determine the underlying genomic cause of these changes, we sequenced pools of SmBRE adults collected during parasite maintenance between 2015 and 2023. We also sequenced another parasite population (SmLE) maintained alongside SmBRE without phenotypic changes. Results: While SmLE allele frequencies remained stable over the eight-year period, we observed sudden changes in allele frequency across the genome in SmBRE between July 2021 and February 2023, consistent with expectations of laboratory contamination. (i) SmLE-specific alleles rose in the SmBRE population from 0 to 41-46% across the genome between September and October 2021, documenting the timing and magnitude of the contamination event. (ii) After contamination, strong selection ( s = ∼0.23) drove replacement of low fitness SmBRE with high fitness SmLE alleles. (iii) Allele frequency changed rapidly across the whole genome, except for a region on chromosome 4 where SmBRE alleles remained at high frequency. Conclusions: We were able to detect contamination in this case because SmBRE shows distinctive phenotypes. However, this would likely have been missed with phenotypically similar parasites. These results provide a cautionary tale about the importance of tracking the identity of parasite populations, but also showcase a simple approach to monitor changes within populations using molecular profiling of pooled population samples to characterize fixed single nucleotide polymorphisms. We also show that genetic drift results in continuous change even in the absence of contamination, causing parasites maintained in different labs (or sampled from the same lab at different times) to diverge.

Genomic data reveal a north-south split and introgression history of blood fluke ( Schistosoma haematobium ) populations from across Africa.

The human parasitic fluke, Schistosoma haematobium hybridizes with the livestock parasite S. bovis in the laboratory, but the extent of hybridization in nature is unclear. We analyzed 34.6 million single nucleotide variants in 162 samples from 18 African countries, revealing a sharp genetic discontinuity between northern and southern S. haematobium . We found no evidence for recent hybridization. Instead the data reveal admixture events that occurred 257-879 generations ago in northern S. haematobium populations. Fifteen introgressed S. bovis genes are approaching fixation in northern S. haematobium with four genes potentially driving adaptation. We identified 19 regions that were resistant to introgression; these were enriched on the sex chromosomes. These results (i) demonstrate strong barriers to gene flow between these species, (ii) indicate that hybridization may be less common than currently envisaged, but (iii) reveal profound genomic consequences of interspecific hybridization between schistosomes of medical and veterinary importance.

Trends and Disparities in Ambulatory Follow-Up After Cardiovascular Hospitalizations : A Retrospective Cohort Study.

BACKGROUND: Timely follow-up after cardiovascular hospitalization is recommended to monitor recovery, titrate medications, and coordinate care. OBJECTIVE: To describe trends and disparities in follow-up after acute myocardial infarction (AMI) and heart failure (HF) hospitalizations. DESIGN: Retrospective cohort study. SETTING: Medicare. PARTICIPANTS: Medicare fee-for-service beneficiaries hospitalized between 2010 and 2019. MEASUREMENTS: Receipt of a cardiology visit within 30 days of discharge. Multivariable logistic regression models were used to estimate changes over time overall and across 5 sociodemographic characteristics on the basis of known disparities in cardiovascular outcomes. RESULTS: The cohort included 1 678 088 AMI and 4 245 665 HF hospitalizations. Between 2010 and 2019, the rate of cardiology follow-up increased from 48.3% to 61.4% for AMI hospitalizations and from 35.2% to 48.3% for HF hospitalizations. For both conditions, follow-up rates increased for all subgroups, yet disparities worsened for Hispanic patients with AMI and patients with HF who were Asian, Black, Hispanic, Medicaid dual eligible, and residents of counties with higher levels of social deprivation. By 2019, the largest disparities were between Black and White patients (AMI, 51.9% vs. 59.8%, difference, 7.9 percentage points [pp] [95% CI, 6.8 to 9.0 pp]; HF, 39.8% vs. 48.7%, difference, 8.9 pp [CI, 8.2 to 9.7 pp]) and Medicaid dual-eligible and non-dual-eligible patients (AMI, 52.8% vs. 60.4%, difference, 7.6 pp [CI, 6.9 to 8.4 pp]; HF, 39.7% vs. 49.4%, difference, 9.6 pp [CI, 9.2 to 10.1 pp]). Differences between hospitals explained 7.3 pp [CI, 6.7 to 7.9 pp] of the variation in follow-up for AMI and 7.7 pp [CI, 7.2 to 8.1 pp]) for HF. LIMITATION: Generalizability to other payers. CONCLUSION: Equity-informed policy and health system strategies are needed to further reduce gaps in follow-up care for patients with AMI and patients with HF. PRIMARY FUNDING SOURCE: National Institute on Aging.

MalKinID: A Likelihood-Based Model for Identifying Malaria Parasite Genealogical Relationships Using Identity-by-Descent.

Pathogen genomics is a powerful tool for tracking infectious disease transmission. In malaria, identity-by-descent (IBD) is used to assess the genetic relatedness between parasites and has been used to study transmission and importation. In theory, IBD can be used to distinguish genealogical relationships to reconstruct transmission history or identify parasites for genotype-to-phenotype quantitative-trait-locus experiments. MalKinID (Malaria Kinship Identifier) is a new likelihood-based classification model designed to identify genealogical relationships among malaria parasites based on genome-wide IBD proportions and IBD segment distributions. MalKinID was calibrated to the genomic data from three laboratory-based genetic crosses (yielding 440 parent-child and 9060 full-sibling comparisons). MalKinID identified lab generated F1 progeny with >80% sensitivity and showed that 0.39 (95% CI 0.28, 0.49) of the second-generation progeny of a NF54 and NHP4026 cross were F1s and 0.56 (0.45, 0.67) were backcrosses of an F1 with the parental NF54 strain. In simulated outcrossed importations, MalKinID accurately reconstructs genealogy history with high precision and sensitivity, with F1-scores exceeding 0.84. However, when importation involves inbreeding, such as during serial co-transmission, the precision and sensitivity of MalKinID declined, with F1-scores of 0.76 (0.56, 0.92) and 0.23 (0.0, 0.4) for PC and FS and <0.05 for second-degree and third-degree relatives. Genealogical inference is most powered 1) when outcrossing is the norm or 2) when multi-sample comparisons based on a predefined pedigree are used. MalKinID lays the foundations for using IBD to track parasite transmission history and for separating progeny for quantitative-trait-locus experiments.

Management of Elevated Blood Pressure in the Hospital-Rethinking Current Practice.

This Clinical Insight proposes a new framework for managing asymptomatic blood pressure elevation in the hospital setting.

Leadership and the high reliability transformation: A qualitative study at Truman VA medical center.

The Department of Veterans Affairs (VA) has committed to becoming a High Reliability Organization (HRO). The Truman VA Medical Center (VAMC) successfully implemented and sustained foundational HRO elements over a period with several changes in facility executive leadership. We interviewed current and past leaders at Truman to understand how they retained fidelity to the HRO transformation. We conducted 16 interviews with 14 leaders involved in the HRO transformation and identified three themes related to the Truman HRO transformation: (1) Leadership visibly drove culture change through intentional communication and modeling HRO principles; (2) Leadership deferred to frontline expertise and empowered staff to make changes and to fail; (3) Hiring the right team members for the organizational culture and investing in training can support HRO principles and values. Our findings highlight key actions for leaders in the context of HROs: regularly communicate the significance of HRO, demonstrate behavior consistent with what they hope to see from staff, celebrate failure, allocate time and resources to the creation of hiring frameworks that identify employee skillsets conducive to HRO principles, and substantial and recurring investments in employee development. Importantly, successive executive leaders at Truman VAMC modeled these skills to promote and sustain the HRO transformation.

Treatment Approaches for Opioid Use Disorder Offered in US Substance Use Treatment Facilities.

This study compares medication and psychosocial treatments for opioid use disorder, as well as treatments offered at opioid and nonopioid treatment program facilities for commonly co-occurring substance use disorders and mental disorders.

Atherosclerotic Cardiovascular Disease Risk Estimates Using the Predicting Risk of Cardiovascular Disease Events Equations.

Importance: In 2023, the American Heart Association (AHA) developed the Predicting Risk of Cardiovascular Disease Events (PREVENT) equations to estimate 10-year risk of atherosclerotic cardiovascular disease (ASCVD), as an update to the 2013 pooled cohort equations (PCEs). The PREVENT equations were derived from contemporary cohorts and removed race and added variables for kidney function and statin use. Objective: To compare national estimates of 10-year ASCVD risk using the PCEs and PREVENT equations and how these equations affect recommendations for primary prevention statin therapy. Design, Setting, and Participants: This cross-sectional study included adults aged 40 to 75 years who participated in the National Health and Nutrition Examination Survey from 2017 to March 2020. Adults were defined as eligible for primary prevention statin use based on the 2019 AHA/American College of Cardiology guideline on the primary prevention of cardiovascular disease. Data were weighted to be nationally representative and were analyzed from December 27, 2023, to January 31, 2024. Main Outcomes and Measures: The 10-year ASCVD risk and eligibility for primary prevention statin therapy based on PREVENT and PCE calculations. Results: In the weighted sample of 3785 US adults (mean [SD] age, 55.7 [9.7] years; 52.5% women) without known ASCVD, 20.7% reported current statin use. The mean estimated 10-year ASCVD risk was 8.0% (95% CI, 7.6%-8.4%) using the PCEs and 4.3% (95% CI, 4.1%-4.5%) using the PREVENT equations. Across all age, sex, and racial subgroups, compared with the PCEs, the mean estimated 10-year ASCVD risk was lower using the PREVENT equations, with the largest difference for Black adults (10.9% [95% CI, 10.1%-11.7%] vs 5.1% [95% CI 4.7%-5.4%]) and individuals aged 70 to 75 years (22.8% [95% CI, 21.6%-24.1%] vs 10.2% [95% CI, 9.6%-10.8%]). The use of the PREVENT equations instead of the PCEs could reduce the number of adults meeting criteria for primary prevention statin therapy from 45.4 million (95% CI, 40.3 million-50.4 million) to 28.3 million (95% CI, 25.2 million-31.4 million). In other words, 17.3 million (95% CI, 14.8 million-19.7 million) adults recommended statins based on the PCEs would no longer be recommended statins based on PREVENT equations, including 4.1 million (95% CI, 2.8 million-5.5 million) adults currently taking statins. Based on the PREVENT equations, 44.1% (95% CI, 38.6%-49.5%) of adults eligible for primary prevention statin therapy reported currently taking statins, equating to 15.8 million (95% CI, 13.4 million-18.2 million) individuals eligible for primary prevention statins who reported not taking statins. Conclusions and Relevance: This cross-sectional study found that use of the PREVENT equations was associated with fewer US adults being eligible for primary prevention statin therapy; however, the majority of adults eligible for receiving such therapy based on PREVENT equations did not report statin use.

A Plasmodium falciparum genetic cross reveals the contributions of pfcrt and plasmepsin II/III to piperaquine drug resistance.

Piperaquine (PPQ) is widely used in combination with dihydroartemisinin as a first-line treatment against malaria. Multiple genetic drivers of PPQ resistance have been reported, including mutations in the Plasmodium falciparum chloroquine resistance transporter (pfcrt) and increased copies of plasmepsin II/III (pm2/3). We generated a cross between a Cambodia-derived multidrug-resistant KEL1/PLA1 lineage isolate (KH004) and a drug-susceptible Malawian parasite (Mal31). Mal31 harbors a wild-type (3D7-like) pfcrt allele and a single copy of pm2/3, while KH004 has a chloroquine-resistant (Dd2-like) pfcrt allele with an additional G367C substitution and multiple copies of pm2/3. We recovered 104 unique recombinant parasites and examined a targeted set of progeny representing all possible combinations of variants at pfcrt and pm2/3. We performed a detailed analysis of competitive fitness and a range of PPQ susceptibility phenotypes with these progenies, including PPQ survival assay, area under the dose response curve, and a limited point IC50. We find that inheritance of the KH004 pfcrt allele is required for reduced PPQ sensitivity, whereas copy number variation in pm2/3 further decreases susceptibility but does not confer resistance in the absence of additional mutations in pfcrt. A deep investigation of genotype-phenotype relationships demonstrates that progeny clones from experimental crosses can be used to understand the relative contributions of pfcrt, pm2/3, and parasite genetic background to a range of PPQ-related traits. Additionally, we find that the resistance phenotype associated with parasites inheriting the G367C substitution in pfcrt is consistent with previously validated PPQ resistance mutations in this transporter.IMPORTANCEResistance to piperaquine, used in combination with dihydroartemisinin, has emerged in Cambodia and threatens to spread to other malaria-endemic regions. Understanding the causal mutations of drug resistance and their impact on parasite fitness is critical for surveillance and intervention and can also reveal new avenues to limiting the evolution and spread of drug resistance. An experimental genetic cross is a powerful tool for pinpointing the genetic determinants of key drug resistance and fitness phenotypes and has the distinct advantage of quantifying the effects of naturally evolved genetic variation. Our study was strengthened since the full range of copies of KH004 pm2/3 was inherited among the progeny clones, allowing us to directly test the role of the pm2/3 copy number on resistance-related phenotypes in the context of a unique pfcrt allele. Our multigene model suggests an important role for both loci in the evolution of this multidrug-resistant parasite lineage.

How should we sample snail microbiomes?

Background: The microbiome is increasingly recognized to shape many aspects of its host biology and is a key determinant of health and disease. The microbiome may influence transmission of pathogens by their vectors, such as mosquitoes or aquatic snails. We previously sequenced the bacterial 16S V4 ribosomal DNA of the hemolymph (blood) of Biomphalaria spp. snails, one of the vectors of the human blood fluke schistosome. We showed that snail hemolymph harbored an abundant and diverse microbiome. This microbiome is distinct from the water environment and can discriminate snail species and populations. As hemolymph bathes snail organs, we then investigated the heterogeneity of the microbiome in these organs. Results: We dissected ten snails for each of two different species (B. alexandrina and B. glabrata) and collected their organs (ovotestis, hepatopancreas, gut, and stomach). We also ground in liquid nitrogen four whole snails of each species. We sampled the water in which the snails were living (environmental controls). Sequencing the 16S V4 rDNA revealed organ-specific microbiomes. These microbiomes harbored a lower diversity than the hemolymph microbiome, and the whole-snail microbiome. The organ microbiomes tend to cluster by physiological function. In addition, we showed that the whole-snail microbiome is more similar to hemolymph microbiome. Conclusions: These results are critical for future work on snail microbiomes and show the necessity of sampling individual organ microbiomes to provide a complete description of snail microbiomes.

Industry Payments to Physicians Endorsing Drugs and Devices on a Social Media Platform.

This study evaluates adherence to industry and professional standards among physicians endorsing drugs and devices on a social media platform.

The Management of Elevated Blood Pressure in the Acute Care Setting: A Scientific Statement From the American Heart Association.

Over the past 3 decades, a substantial body of high-quality evidence has guided the diagnosis and management of elevated blood pressure (BP) in the outpatient setting. In contrast, there is a lack of comparable evidence for guiding the management of elevated BP in the acute care setting, resulting in significant practice variation. Throughout this scientific statement, we use the terms acute care and inpatient to refer to care received in the emergency department and after admission to the hospital. Elevated inpatient BP is common and can manifest either as asymptomatic or with signs of new or worsening target-organ damage, a condition referred to as hypertensive emergency. Hypertensive emergency involves acute target-organ damage and should be treated swiftly, usually with intravenous antihypertensive medications, in a closely monitored setting. However, the risk-benefit ratio of initiating or intensifying antihypertensive medications for asymptomatic elevated inpatient BP is less clear. Despite this ambiguity, clinicians prescribe oral or intravenous antihypertensive medications in approximately one-third of cases of asymptomatic elevated inpatient BP. Recent observational studies have suggested potential harms associated with treating asymptomatic elevated inpatient BP, which brings current practice into question. Despite the ubiquity of elevated inpatient BPs, few position papers, guidelines, or consensus statements have focused on improving BP management in the acute care setting. Therefore, this scientific statement aims to synthesize the available evidence, provide suggestions for best practice based on the available evidence, identify evidence-based gaps in managing elevated inpatient BP (asymptomatic and hypertensive emergency), and highlight areas requiring further research.

Contribution of parasite and host genotype to immunopathology of schistosome infections.

BACKGROUND: The role of pathogen genotype in determining disease severity and immunopathology has been studied intensively in microbial pathogens including bacteria, fungi, protozoa and viruses but is poorly understood in parasitic helminths. The medically important blood fluke Schistosoma mansoni is an excellent model system to study the impact of helminth genetic variation on immunopathology. Our laboratory has demonstrated that laboratory schistosome populations differ in sporocyst growth and cercarial production in the intermediate snail host and worm establishment and fecundity in the vertebrate host. Here, we (i) investigate the hypothesis that schistosome genotype plays a significant role in immunopathology and related parasite life history traits in the vertebrate mouse host and (ii) quantify the relative impact of parasite and host genetics on infection outcomes. METHODS: We infected BALB/c and C57BL/6 mice with four different laboratory schistosome populations from Africa and the Americas. We quantified disease progression in the vertebrate host by measuring body weight and complete blood count (CBC) with differential over a 12-week infection period. On sacrifice, we assessed parasitological (egg and worm counts, fecundity), immunopathological (organ measurements and histopathology) and immunological (CBC with differential and cytokine profiles) characteristics to determine the impact of parasite and host genetics. RESULTS: We found significant variation between parasite populations in worm numbers, fecundity, liver and intestine egg counts, liver and spleen weight, and fibrotic area but not in granuloma size. Variation in organ weight was explained by egg burden and intrinsic parasite factors independent of egg burden. We found significant variation between infected mouse lines in cytokine levels (IFN-γ, TNF-α), eosinophils, lymphocytes and monocyte counts. CONCLUSIONS: This study showed that both parasite and host genotype impact the outcome of infection. While host genotype explains most of the variation in immunological traits, parasite genotype explains most of the variation in parasitological traits, and both host and parasite genotypes impact immunopathology outcomes.

Management of Inpatient Elevated Blood Pressures : A Systematic Review of Clinical Practice Guidelines.

BACKGROUND: Management of elevated blood pressure (BP) during hospitalization varies widely, with many hospitalized adults experiencing BPs higher than those recommended for the outpatient setting. PURPOSE: To systematically identify guidelines on elevated BP management in the hospital. DATA SOURCES: MEDLINE, Guidelines International Network, and specialty society websites from 1 January 2010 to 29 January 2024. STUDY SELECTION: Clinical practice guidelines pertaining to BP management for the adult and older adult populations in ambulatory, emergency department, and inpatient settings. DATA EXTRACTION: Two authors independently screened articles, assessed quality, and extracted data. Disagreements were resolved via consensus. Recommendations on treatment targets, preferred antihypertensive classes, and follow-up were collected for ambulatory and inpatient settings. DATA SYNTHESIS: Fourteen clinical practice guidelines met inclusion criteria (11 were assessed as high-quality per the AGREE II [Appraisal of Guidelines for Research & Evaluation II] instrument), 11 provided broad BP management recommendations, and 1 each was specific to the emergency department setting, older adults, and hypertensive crises. No guidelines provided goals for inpatient BP or recommendations for managing asymptomatic moderately elevated BP in the hospital. Six guidelines defined hypertensive urgency as BP above 180/120 mm Hg, with hypertensive emergencies requiring the addition of target organ damage. Hypertensive emergency recommendations consistently included use of intravenous antihypertensives in intensive care settings. Recommendations for managing hypertensive urgencies were inconsistent, from expert consensus, and focused on the emergency department. Outpatient treatment with oral medications and follow-up in days to weeks were most often advised. In contrast, outpatient BP goals were clearly defined, varying between 130/80 and 140/90 mm Hg. LIMITATION: Exclusion of non-English-language guidelines and guidelines specific to subpopulations. CONCLUSION: Despite general consensus on outpatient BP management, guidance on inpatient management of elevated BP without symptoms is lacking, which may contribute to variable practice patterns. PRIMARY FUNDING SOURCE: National Institute on Aging. (PROSPERO: CRD42023449250).

Intravascular Microaxial Left Ventricular Assist Device Manufacturer Payments to Cardiologists and Use of Devices.

This study examines whether payments from a left ventricular assist device manufacturer to cardiologists performing percutaneous coronary intervention were associated with any use of the devices.

Medicare Transitional Care Management Program and Changes in Timely Postdischarge Follow-Up.

Importance: In 2013, Medicare implemented payments for transitional care management (TCM) services, which provide increased reimbursement to clinicians providing ambulatory care to patients after discharge from medical facilities to the community. Objective: To determine whether the introduction of TCM payments was associated with an increase in timely postdischarge follow-up. Design, Setting, and Participants: This cross-sectional interrupted time-series study assessed quarterly postdischarge visit rates before (2010-2012) and after (2013-2019) TCM implementation 100% sample of Medicare fee-for-service beneficiaries discharged to the community after a hospital or skilled nursing facility stay. Data analyses were performed February 1 to December 15, 2023. Exposure: Implementation of payments for TCM. Main Outcomes and Measures: Timely postdischarge primary care follow-up, defined as receipt of a primary care ambulatory visit within 14 days of discharge. Secondary outcomes included receipt of a TCM visit and specialty care follow-up. Results: The study sample comprised 79 125 965 eligible discharges. Of these, 55.4% were female; 1.5% were Asian, 12.1% Black, 5.6% Hispanic, and 79.0% were White individuals; and 79.6% were beneficiaries aged 65 years and older. Timely primary care follow-up increased from 31.5% in 2010 to 38.8% in 2019 (absolute increase 7.3%), whereas specialist follow-up increased from 27.6% to 30.8% (absolute increase 3.2%). By 2019, 11.3% of eligible patients received TCM services. Interrupted time-series analyses demonstrated an increased slope of timely primary care follow-up after the introduction of TCM services (pre-TCM slope, 0.12% per quarter vs post-TCM slope, 0.29% per quarter; difference, 0.13%; 95% CI, 0.02% to 0.22%). Receipt of timely follow-up increased for all demographic groups; however, Black, Hispanic, and Medicaid dual-eligible patients and patients residing in urban areas and counties with high-level social deprivation were less likely to receive follow-up during the study period. These disparities widened for Black patients (difference-in-differences in pre-TCM vs post-TCM slope, -0.14%; 95% CI, -0.25% to -0.2%) and patients who were Medicaid dual-eligible (difference-in-differences pre-TCM vs post-TCM slope, -0.21%; 95% CI, -0.35% to -0.07%). Conclusions: These findings indicate that Medicare's introduction of payments for TCM services was associated with a persistent increase in the rate of timely postdischarge primary care but did not narrow demographic or socioeconomic disparities. Most beneficiaries did not receive timely primary care follow-up.