Malaria parasite clag3 genes determine channel-mediated nutrient uptake by infected red blood cells.

Development of malaria parasites within vertebrate erythrocytes requires nutrient uptake at the host cell membrane. The plasmodial surface anion channel (PSAC) mediates this transport and is an antimalarial target, but its molecular basis is unknown. We report a parasite gene family responsible for PSAC activity. We used high-throughput screening for nutrient uptake inhibitors to identify a compound highly specific for channels from the Dd2 line of the human pathogen P. falciparum. Inheritance of this compound's affinity in a Dd2 × HB3 genetic cross maps to a single parasite locus on chromosome 3. DNA transfection and in vitro selections indicate that PSAC-inhibitor interactions are encoded by two clag3 genes previously assumed to function in cytoadherence. These genes are conserved in plasmodia, exhibit expression switching, and encode an integral protein on the host membrane, as predicted by functional studies. This protein increases host cell permeability to diverse solutes.

NK cell-induced damage to P.falciparum-infected erythrocytes requires ligand-specific recognition and releases parasitophorous vacuoles that are phagocytosed by monocytes in the presence of immune IgG.

Natural killer (NK) cells lyse virus-infected cells and transformed cells through polarized delivery of lytic effector molecules into target cells. We have shown that NK cells lyse Plasmodium falciparum-infected red blood cells (iRBC) via antibody-dependent cellular cytotoxicity (ADCC). A high frequency of adaptive NK cells, with elevated intrinsic ADCC activity, in people chronically exposed to malaria transmission is associated with reduced parasitemia and resistance to disease. How NK cells bind to iRBC and the outcome of iRBC lysis by NK cells has not been investigated. We applied gene ablation in inducible erythrocyte precursors and antibody-blocking experiments with iRBC to demonstrate a central role of CD58 and ICAM-4 as ligands for adhesion by NK cells via CD2 and integrin αMß2, respectively. Adhesion was dependent on opsonization of iRBC by IgG. Live imaging and quantitative flow cytometry of NK-mediated ADCC toward iRBC revealed that damage to the iRBC plasma membrane preceded damage to P. falciparum within parasitophorous vacuoles (PV). PV were identified and tracked with a P.falciparum strain that expresses the PV membrane-associated protein EXP2 tagged with GFP. After NK-mediated ADCC, PV were either found inside iRBC ghosts or released intact and devoid of RBC plasma membrane. Electron microscopy images of ADCC cultures revealed tight NK-iRBC synapses and free vesicles similar in size to GFP+ PV isolated from iRBC lysates by cell sorting. The titer of IgG in plasma of malaria-exposed individuals that bound PV was two orders of magnitude higher than IgG that bound iRBC. This immune IgG stimulated efficient phagocytosis of PV by primary monocytes. The selective NK-mediated damage to iRBC, resulting in release of PV, and subsequent phagocytosis of PV by monocytes may combine for efficient killing and removal of intra-erythrocytic P.falciparum parasite. This mechanism may mitigate the inflammation and malaria symptoms during blood-stage P. falciparum infection.

A robust fluorescence-based assay for human erythrocyte Ca++ efflux suitable for high-throughput inhibitor screens.

Intracellular calcium is maintained at very low concentrations through the action of PMCA Ca++ extrusion pumps. Although much of our knowledge about these Ca++ extrusion pumps derives from studies with human erythrocytes, kinetic studies of Ca++ transport for these cells are limited to radioisotope flux measurements. Here, we developed a robust, microplate-based assay for erythrocyte Ca++ efflux using extracellular fluorescent Ca++ indicators. We optimized Ca++ loading with the A23187 ionophore, established conditions for removal of the ionophore, and adjusted fluorescent dye sensitivity by addition of extracellular EGTA to allow continuous tracking of Ca++ efflux. Efflux kinetics were accelerated by glucose and inhibited in a dose-dependent manner by the nonspecific inhibitor vanadate, revealing that Ca++ pump activity can be tracked in a 384-well microplate format. These studies enable radioisotope-free kinetic measurements of the Ca++ pump and should facilitate screens for specific inhibitors of this essential transport activity.

Using poetry to elicit internal medicine residents' perspectives on wellness.

PURPOSE: To elicit internal medicine residents' perspectives on wellness through poetry writing, examining (1) response rates, (2) the tone/sentiment of their submissions and (3) the primary thematic content. STUDY DESIGN: In academic year 2019-2020, a random sample of 88 residents from four internal medicine residency programmes was invited to participate in a year-long study of wellness. In December 2019, an open-ended prompt asked residents to write a poem reflecting on their well-being. Responses were inductively coded using content analysis techniques. RESULTS: The response rate for the poetry prompt was 94%. The tone of the entries was most often neutral or contradictory (42%), followed by negative (33%) and positive (25%). There were three main themes: (1) Mindsets: most residents simply wanted to make it through their programme; (2) wellness influencers: the main wellness supporters were external to the programme such as vacationing and exercise; within hospitals, friendships with colleagues and boosted wellness and (3) scheduling/repetition: difficult schedules drained energy as did the monotony of administrative tasks. CONCLUSIONS: Poetry appears to be an innovative and effective vehicle to elicit residents' perspectives without compromising response rate. Poetry survey techniques allow medical trainees to provide powerful messaging to leadership. Most of what is known about trainee wellness is derived from quantitative surveys. This study showed medicine trainees' willingness to engage in poetry and add richness and personal detail to highlight key drivers of wellness. Such information provides context and brings attention in a compelling manner to an important topic.

An Invariant Protein That Colocalizes With VAR2CSA on Plasmodium falciparum-Infected Red Cells Binds to Chondroitin Sulfate A.

BACKGROUND: Plasmodium falciparum-infected red blood cells (iRBCs) bind and sequester in deep vascular beds, causing malaria-related disease and death. In pregnant women, VAR2CSA binds to chondroitin sulfate A (CSA) and mediates placental sequestration, making it the major placental malaria (PM) vaccine target. METHODS: In this study, we characterize an invariant protein associated with PM called P falciparum chondroitin sulfate A ligand (PfCSA-L). RESULTS: Recombinant PfCSA-L binds both placental CSA and VAR2CSA with nanomolar affinity, and it is coexpressed on the iRBC surface with VAR2CSA. Unlike VAR2CSA, which is anchored by a transmembrane domain, PfCSA-L is peripherally associated with the outer surface of knobs through high-affinity protein-protein interactions with VAR2CSA. This suggests that iRBC sequestration involves complexes of invariant and variant surface proteins, allowing parasites to maintain both diversity and function at the iRBC surface. CONCLUSIONS: The PfCSA-L is a promising target for intervention because it is well conserved, exposed on infected cells, and expressed and localized with VAR2CSA.

Optimized Pyridazinone Nutrient Channel Inhibitors Are Potent and Specific Antimalarial Leads.

Human and animal malaria parasites increase their host erythrocyte permeability to a broad range of solutes as mediated by parasite-associated ion channels. Molecular and pharmacological studies have implicated an essential role in parasite nutrient acquisition, but inhibitors suitable for development of antimalarial drugs are missing. Here, we generated a potent and specific drug lead using Plasmodium falciparum, a virulent human pathogen, and derivatives of MBX-2366, a nanomolar affinity pyridazinone inhibitor from a high-throughput screen. As this screening hit lacks the bioavailability and stability needed for in vivo efficacy, we synthesized 315 derivatives to optimize drug-like properties, establish target specificity, and retain potent activity against the parasite-induced permeability. Using a robust, iterative pipeline, we generated MBX-4055, a derivative active against divergent human parasite strains. MBX-4055 has improved oral absorption with acceptable in vivo tolerability and pharmacokinetics. It also has no activity against a battery of 35 human channels and receptors and is refractory to acquired resistance during extended in vitro selection. Single-molecule and single-cell patch-clamp indicate direct action on the plasmodial surface anion channel, a channel linked to parasite-encoded RhopH proteins. These studies identify pyridazinones as novel and tractable antimalarial scaffolds with a defined mechanism of action. SIGNIFICANCE STATEMENT: Because antimalarial drugs are prone to evolving resistance in the virulent human P. falciparum pathogen, new therapies are needed. This study has now developed a novel drug-like series of pyridazinones that target an unexploited parasite anion channel on the host cell surface, display excellent in vitro and in vivo ADME properties, are refractory to acquired resistance, and demonstrate a well defined mechanism of action.

Patient Safety Outcomes under Flexible and Standard Resident Duty-Hour Rules.

BACKGROUND: Concern persists that extended shifts in medical residency programs may adversely affect patient safety. METHODS: We conducted a cluster-randomized noninferiority trial in 63 internal-medicine residency programs during the 2015-2016 academic year. Programs underwent randomization to a group with standard duty hours, as adopted by the Accreditation Council for Graduate Medical Education (ACGME) in July 2011, or to a group with more flexible duty-hour rules that did not specify limits on shift length or mandatory time off between shifts. The primary outcome for each program was the change in unadjusted 30-day mortality from the pretrial year to the trial year, as ascertained from Medicare claims. We hypothesized that the change in 30-day mortality in the flexible programs would not be worse than the change in the standard programs (difference-in-difference analysis) by more than 1 percentage point (noninferiority margin). Secondary outcomes were changes in five other patient safety measures and risk-adjusted outcomes for all measures. RESULTS: The change in 30-day mortality (primary outcome) among the patients in the flexible programs (12.5% in the trial year vs. 12.6% in the pretrial year) was noninferior to that in the standard programs (12.2% in the trial year vs. 12.7% in the pretrial year). The test for noninferiority was significant (P = 0.03), with an estimate of the upper limit of the one-sided 95% confidence interval (0.93%) for a between-group difference in the change in mortality that was less than the prespecified noninferiority margin of 1 percentage point. Differences in changes between the flexible programs and the standard programs in the unadjusted rate of readmission at 7 days, patient safety indicators, and Medicare payments were also below 1 percentage point; the noninferiority criterion was not met for 30-day readmissions or prolonged length of hospital stay. Risk-adjusted measures generally showed similar findings. CONCLUSIONS: Allowing program directors flexibility in adjusting duty-hour schedules for trainees did not adversely affect 30-day mortality or several other measured outcomes of patient safety. (Funded by the National Heart, Lung, and Blood Institute and Accreditation Council for Graduate Medical Education; iCOMPARE ClinicalTrials.gov number, NCT02274818.).

Sleep and Alertness in a Duty-Hour Flexibility Trial in Internal Medicine.

BACKGROUND: A purpose of duty-hour regulations is to reduce sleep deprivation in medical trainees, but their effects on sleep, sleepiness, and alertness are largely unknown. METHODS: We randomly assigned 63 internal-medicine residency programs in the United States to follow either standard 2011 duty-hour policies or flexible policies that maintained an 80-hour workweek without limits on shift length or mandatory time off between shifts. Sleep duration and morning sleepiness and alertness were compared between the two groups by means of a noninferiority design, with outcome measures including sleep duration measured with actigraphy, the Karolinska Sleepiness Scale (with scores ranging from 1 [extremely alert] to 9 [extremely sleepy, fighting sleep]), and a brief computerized Psychomotor Vigilance Test (PVT-B), with long response times (lapses) indicating reduced alertness. RESULTS: Data were obtained over a period of 14 days for 205 interns at six flexible programs and 193 interns at six standard programs. The average sleep time per 24 hours was 6.85 hours (95% confidence interval [CI], 6.61 to 7.10) among those in flexible programs and 7.03 hours (95% CI, 6.78 to 7.27) among those in standard programs. Sleep duration in flexible programs was noninferior to that in standard programs (between-group difference, -0.17 hours per 24 hours; one-sided lower limit of the 95% confidence interval, -0.45 hours; noninferiority margin, -0.5 hours; P = 0.02 for noninferiority), as was the score on the Karolinska Sleepiness Scale (between-group difference, 0.12 points; one-sided upper limit of the 95% confidence interval, 0.31 points; noninferiority margin, 1 point; P<0.001). Noninferiority was not established for alertness according to the PVT-B (between-group difference, -0.3 lapses; one-sided upper limit of the 95% confidence interval, 1.6 lapses; noninferiority margin, 1 lapse; P = 0.10). CONCLUSIONS: This noninferiority trial showed no more chronic sleep loss or sleepiness across trial days among interns in flexible programs than among those in standard programs. Noninferiority of the flexible group for alertness was not established. (Funded by the National Heart, Lung, and Blood Institute and American Council for Graduate Medical Education; ClinicalTrials.gov number, NCT02274818.).

Complex nutrient channel phenotypes despite Mendelian inheritance in a Plasmodium falciparum genetic cross.

Malaria parasites activate a broad-selectivity ion channel on their host erythrocyte membrane to obtain essential nutrients from the bloodstream. This conserved channel, known as the plasmodial surface anion channel (PSAC), has been linked to parasite clag3 genes in P. falciparum, but epigenetic switching between the two copies of this gene hinders clear understanding of how the encoded protein determines PSAC activity. Here, we used linkage analysis in a P. falciparum cross where one parent carries a single clag3 gene to overcome the effects of switching and confirm a primary role of the clag3 product with high confidence. Despite Mendelian inheritance, CLAG3 conditional knockdown revealed remarkably preserved nutrient and solute uptake. Even more surprisingly, transport remained sensitive to a CLAG3 isoform-specific inhibitor despite quantitative knockdown, indicating that low doses of the CLAG3 transgene are sufficient to confer block. We then produced a complete CLAG3 knockout line and found it exhibits an incomplete loss of transport activity, in contrast to rhoph2 and rhoph3, two PSAC-associated genes that cannot be disrupted because nutrient uptake is abolished in their absence. Although the CLAG3 knockout did not incur a fitness cost under standard nutrient-rich culture conditions, this parasite could not be propagated in a modified medium that more closely resembles human plasma. These studies implicate oligomerization of CLAG paralogs encoded by various chromosomes in channel formation. They also reveal that CLAG3 is dispensable under standard in vitro conditions but required for propagation under physiological conditions.

Models of Intermediate Care Organization and Staffing at an Academic Medical Center: Considerations of an Inpatient Planning Committee.

Rationale: Geographic co-localization of patients and provider teams (geography) may improve care efficiency and quality. Patients requiring intermediate care present a unique challenge to the geographic model. Objective: Identify the best organizational and staffing model for intermediate care at our academic medical center. Methods: A modified nominal group technique was employed to assess the benefits and limitations of an existing model of intermediate care, identify and review potential alternative models, and choose a new model. Results: In addition to the institution's current model, the benefits and limitations of six alternative organizational and staffing models were characterized. The anticipated impact of each model on nurse: provider communication, maintenance of nursing competencies, nurse satisfaction, efficient utilization of technical and human resources, triage of patients to the unit, care continuity, and the impact on trainee education are described. After considering these features, stakeholders ranked a closed provider staffing model on a unit dedicated to intermediate care highest of the six alternative models. Important outcomes to monitor following transition to a closed staffing model included patient outcomes, nursing job satisfaction and retention, provider and trainee experience, unexpected patient transfers to higher or lower levels of care, and administrative costs. Conclusions: After considering six alternative staffing models for intermediate care, stakeholders ranked a closed provider staffing model highest. Further qualitative and quantitative comparisons to determine optimal models of intermediate care are needed.

An International Delphi Consensus on Diagnostic Criteria for Buerger's Disease.

BACKGROUND: Buerger's disease (BD) remains a debilitating condition. Despite multiple published diagnostic criteria for BD, none is universally accepted as a gold standard. METHODS: We conducted a 2-round modified Delphi consensus study to establish a consensus on the diagnostic. The questionnaire included statements from several commonly used diagnostic criteria for BD. Qualitative and quantitative analysis methods were performed. An agreement level of 70% was applied. RESULTS: Twenty nine experts from 18 countries participated in this study. Overall, 75 statements were circulated in Round 1. Of these, 28% of statements were accepted. Following comments, 21 statements were recirculated in Round 2 and 90% were accepted. Although more than 90% of the experts did not agree that the diagnosis of BD can be based only on clinical manifestation, none of the nonclinical manifestations of BD were agreed as a part of the diagnostic criteria. There was an agreement that a history of tobacco consumption in any form, not necessarily confined to the current use, should be a part of the diagnostic criteria of BD. The history of thrombophlebitis migrans, even if not present at presentation, was accepted as a clue for BD diagnosis. It was also agreed that discoloration of the toes or fingers could be included in the diagnostic criteria of BD. Experts agreed that histology results could differentiate BD from atherosclerosis obliterans and other types of vasculitis. The presence of corkscrew collaterals on imaging and burning pain reached the agreement at the first round but not at the second. There was no consensus regarding age cut-off, the requirement of normal lipid profile, and normal blood glucose for BD diagnosis. CONCLUSIONS: The present study demonstrated discrepancies in the various published diagnostic criteria for BD and their selective utilization in routine clinical practice worldwide. We propose that all published diagnostic criteria for BD be re-evaluated for harmonization and universal use.

Evaluation of house staff candidates for program fit: a cohort-based controlled study.

BACKGROUND: Medical school academic achievements do not necessarily predict house staff job performance. This study explores a selection mechanism that improves house staff-program fit that enhances the Accreditation Council for Graduate Medical Education Milestones performance ratings. OBJECTIVE: Traditionally, house staff were selected primarily on medical school academic performance. To improve residency performance outcomes, the Program designed a theory-driven selection tool to assess house staff candidates on their personal values and goals fit with Program values and goals. It was hypothesized cohort performance ratings will improve because of the intervention. METHODS: Prospective quasi-experimental cohort design with data from two house staff cohorts at a university-based categorical Internal Medicine Residency Program. The intervention cohort, comprising 45 house staff from 2016 to 2017, was selected using a Behaviorally Anchored Rating Scales (BARS) tool for program fit. The control cohort, comprising 44 house staff from the prior year, was selected using medical school academic achievement scores. House staff performance was evaluated using ACGME Milestones indicators. The mean scores for each category were compared between the intervention and control cohorts using Student's t-tests with Bonferroni correction and Cohen's d for effect size. RESULTS: The cohorts were no different in academic performance scores at time of Program entry. The intervention cohort outperformed the control cohort on all 6 dimensions of Milestones by end-PGY1 and 3 of 6 dimensions by mid-PGY3. CONCLUSION: Selecting house staff based on compatibility with Residency Program values and objectives may yield higher job performance because trainees benefit more from a better fit with the training program.

Efficacy and safety of CARTIGROW® in patients with articular cartilage defects of the knee joint: a four year prospective studys.

INTRODUCTION: Research shows autologous chondrocyte implantation (ACI) is a promising treatment for articular cartilage lesions. In this study, we assessed mid-term efficacy and safety of gel-based ACI or autologous adult live cultured chondrocytes (CARTIGROW®) implantation in patients with cartilage defects of the knee joint. METHODS: In this prospective, open-label study, patients (19-38 years) with focal, international cartilage repair society grade III or IV articular cartilage defects of the knee joint were enroled at four centres across India from April 2015 to September 2015. Punch biopsy was conducted to harvest cartilage, from which chondrocytes were isolated and cultured, and the characterised chondrocytes were implanted into the cartilage defect. Key efficacy outcomes were assessed by quantitative changes in international knee documentation committee (IKDC), visual analogue scale (VAS) scores, and qualitative changes in magnetic resonance imaging at six months and four years from baseline. RESULTS: Of the14 patients enroled in the study, all patients completed the six month follow-up and 11 completed the four year follow-up. The IKDC score improved significantly from 32.84 ± 9.25 at baseline to 67.49 ± 13.03 at six months (mean difference [MD] 34.66 ± 13.00, p < 0.0001) and to 60.18 ± 10.33 at four years (MD 28.21 ± 15.14, p = 0.0001). The VAS score reduced from 72.00 ± 14.40 at baseline to 16.64 ± 17.03 at six months (MD 55.36 ± 24.50, p < 0.0001) and further to 12.72 ± 9.05 at four years (MD 62.09 ± 10.66, p < 0.0001). All patients showed improvement on MRI of the knee joint. No adverse events were reported. CONCLUSION: Autologous adult live cultured chondrocytes (CARTIGROW®) implantation showed good mid-term efficacy in patients with cartilage defects of the knee joint with no side-effects.

Education Outcomes in a Duty-Hour Flexibility Trial in Internal Medicine.

BACKGROUND: Concern persists that inflexible duty-hour rules in medical residency programs may adversely affect the training of physicians. METHODS: We randomly assigned 63 internal medicine residency programs in the United States to be governed by standard duty-hour policies of the 2011 Accreditation Council for Graduate Medical Education (ACGME) or by more flexible policies that did not specify limits on shift length or mandatory time off between shifts. Measures of educational experience included observations of the activities of interns (first-year residents), surveys of trainees (both interns and residents) and faculty, and intern examination scores. RESULTS: There were no significant between-group differences in the mean percentages of time that interns spent in direct patient care and education nor in trainees' perceptions of an appropriate balance between clinical demands and education (primary outcome for trainee satisfaction with education; response rate, 91%) or in the assessments by program directors and faculty of whether trainees' workload exceeded their capacity (primary outcome for faculty satisfaction with education; response rate, 90%). Another survey of interns (response rate, 49%) revealed that those in flexible programs were more likely to report dissatisfaction with multiple aspects of training, including educational quality (odds ratio, 1.67; 95% confidence interval [CI], 1.02 to 2.73) and overall well-being (odds ratio, 2.47; 95% CI, 1.67 to 3.65). In contrast, directors of flexible programs were less likely to report dissatisfaction with multiple educational processes, including time for bedside teaching (response rate, 98%; odds ratio, 0.13; 95% CI, 0.03 to 0.49). Average scores (percent correct answers) on in-training examinations were 68.9% in flexible programs and 69.4% in standard programs; the difference did not meet the noninferiority margin of 2 percentage points (difference, -0.43; 95% CI, -2.38 to 1.52; P=0.06 for noninferiority). od Institute and the ACGME; iCOMPARE ClinicalTrials.gov number, NCT02274818 .). CONCLUSIONS: There was no significant difference in the proportion of time that medical interns spent on direct patient care and education between programs with standard duty-hour policies and programs with more flexible policies. Interns in flexible programs were less satisfied with their educational experience than were their peers in standard programs, but program directors were more satisfied. (Funded by the National Heart, Lung, and Blo

Improved Plasmodium falciparum dilution cloning through efficient quantification of parasite numbers and c-SNARF detection.

BACKGROUND: Molecular and genetic studies of blood-stage Plasmodium falciparum parasites require limiting dilution cloning and prolonged cultivation in microplates. The entire process is laborious and subject to errors due to inaccurate dilutions at the onset and failed detection of parasite growth in individual microplate wells. METHODS: To precisely control the number of parasites dispensed into each microplate well, parasitaemia and total cell counts were determined by flow cytometry using parasite cultures stained with ethidium bromide or SYBR Green I. Microplates were seeded with 0.2 or 0.3 infected cells/well and cultivated with fresh erythrocytes. The c-SNARF fluorescent pH indicator was then used to reliably detect parasite growth. RESULTS: Flow cytometry required less time than the traditional approach of estimating parasitaemia and cell numbers by microscopic examination. The resulting dilutions matched predictions from Poisson distribution calculations and yielded clonal lines. Addition of c-SNARF to media permitted rapid detection of parasite growth in microplate wells with high confidence. CONCLUSION: The combined use of flow cytometry for precise dilution and the c-SNARF method for detection of growth improves limiting dilution cloning of P. falciparum. This simple approach saves time, is scalable, and maximizes identification of desired parasite clones. It will facilitate DNA transfection studies and isolation of parasite clones from ex vivo blood samples.

Arthroscopic Bankart Repair With and Without Curettage of the Glenoid Edge: A Prospective, Randomized, Controlled Study.

PURPOSE: To determine whether curettage of the cartilage on the glenoid edge in arthroscopic Bankart repair reduces the postoperative recurrence rate compared with noncuretted glenoid. METHODS: Between January 2010 and December 2013, 134 patients underwent arthroscopy and stabilization for recurrent anterior dislocation of shoulder; 42 patients were excluded. Alternate glenoid edge was curetted in 92 patients undergoing arthroscopic Bankart repair. Twelve patients were lost to follow-up. The remaining 80 patients were divided into 2 groups of 40 patients each, curettage and noncurettage. In both groups, the Bankart lesion was repaired using ≥3 bioanchors loaded with nonabsorbable braided sutures. Postoperative rehabilitation was the same for the 2 groups. We recorded recurrence of instability, pain, and Constant and Rowe shoulder scores. Statistical analysis of data was performed using unpaired t test (significance level P < .05). RESULTS: The 2 groups were comparable in terms of age, number of dislocations, and bone loss. The average follow-up was 7 years and 9 months (range 6 to 10 years). Of the total 40 patients in the curettage group, 6 (15%) had recurrence of dislocation and none had subluxations, whereas in the noncurettage group, 13 (32.5%) had recurrence of dislocation and 3 (7.5%) had subluxations. The difference in postoperative recurrence of instability was statistically significant (P = .012). The average (standard deviation) Rowe score was 83.75 (23.28) in the curettage group and 70.13 (31.29) in the noncurettage group (P = .030). CONCLUSIONS: During arthroscopic Bankart repair, curettage of the cartilage on the anterior glenoid edge reduces the incidence of postoperative recurrence of instability. LEVEL OF EVIDENCE: II, therapeutic; prospective, randomized, controlled study.

Does This Patient Need Blood Cultures? A Scoping Review of Indications for Blood Cultures in Adult Nonneutropenic Inpatients.

Guidance regarding indications for initial or follow-up blood cultures is limited. We conducted a scoping review of articles published between January 2004 and June 2019 that reported the yield of blood cultures and/or their impact in the clinical management of fever and common infectious syndromes in nonneutropenic adult inpatients. A total of 2893 articles were screened; 50 were included. Based on the reported incidence of bacteremia, syndromes were categorized into low, moderate, and high pretest probability of bacteremia. Routine blood cultures are recommended in syndromes with a high likelihood of bacteremia (eg, endovascular infections) and those with moderate likelihood when cultures from the primary source of infection are unavailable or when prompt initiation of antibiotics is needed prior to obtaining primary source cultures. In syndromes where blood cultures are low-yield, blood cultures can be considered for patients at risk of adverse events if a bacteremia is missed (eg, patient with pacemaker and severe purulent cellulitis). If a patient has adequate source control and risk factors or concern for endovascular infection are not present, most streptococci or Enterobacterales bacteremias do not require routine follow-up blood cultures.

A Diagnostic Stewardship Intervention To Improve Blood Culture Use among Adult Nonneutropenic Inpatients: the DISTRIBUTE Study.

Interventions to optimize blood culture (BCx) practices in adult inpatients are limited. We conducted a before-after study evaluating the impact of a diagnostic stewardship program that aimed to optimize BCx use in a medical intensive care unit (MICU) and five medicine units at a large academic center. The program included implementation of an evidence-based algorithm detailing indications for BCx use and education and feedback to providers about BCx rates and indication inappropriateness. Neutropenic patients were excluded. BCx rates from contemporary control units were obtained for comparison. The primary outcome was the change in BCxs ordered with the intervention. Secondary outcomes included proportion of inappropriate BCx, solitary BCx, and positive BCx. Balancing metrics included compliance with the Centers for Medicare and Medicaid Services (CMS) SEP-1 BCx component, 30-day readmission, and all-cause in-hospital and 30-day mortality. After the intervention, BCx rates decreased from 27.7 to 22.8 BCx/100 patient-days (PDs) in the MICU (P = 0.001) and from 10.9 to 7.7 BCx/100 PD for the 5 medicine units combined (P < 0.001). BCx rates in the control units did not decrease significantly (surgical intensive care unit [ICU], P = 0.06; surgical units, P = 0.15). The proportion of inappropriate BCxs did not significantly change with the intervention (30% in the MICU and 50% in medicine units). BCx positivity increased in the MICU (from 8% to 11%, P < 0.001). Solitary BCxs decreased by 21% in the medicine units (P < 0.001). Balancing metrics were similar before and after the intervention. BCx use can be optimized with clinician education and practice guidance without affecting sepsis quality metrics or mortality.

Does Increased Schedule Flexibility Lead to Change? A National Survey of Program Directors on 2017 Work Hours Requirements.

BACKGROUND: The learning and working environment for resident physicians shifted dramatically over the past two decades, with increased focus on work hours, resident wellness, and patient safety. Following two multi-center randomized trials comparing 16-h work limits for PGY-1 trainees to more flexible rules, the ACGME implemented new flexible work hours standards in 2017. OBJECTIVE: We sought to determine program directors' (PDs) support for the work hour changes and programmatic response. DESIGN: In 2017, US Internal Medicine PDs were surveyed about their degree of support for extension of PGY-1 work hour limits, whether they adopted the new maximum continuous work hours permitted, and reasons for their decisions. KEY RESULTS: The response rate was 70% (266/379). Fifty-seven percent of PDs (n = 151) somewhat/strongly support the new work hour rules for PGY-1 residents, while only 25% of programs (N = 66) introduced work periods greater than 16-h on any rotation. Higher rates of adopting change were seen in PDs who strongly/somewhat supported the change (56/151 [37%], P < 0.001), had tenure of 6+ years (33/93 [35%], P = 0.005), were of non-general internal medicine subspecialty (30/80 [38%], P = 0.003), at university-based programs (35/101 [35%], P = 0.009), and with increasing number of approved positions (< 38, 10/63 [16%]; 38-58, 13/69 [19%]; 59-100, 15/64 [23%]; > 100, 28/68 [41%], P = 0.005). Areas with the greatest influence for PDs not extending work hours were the 16-h rule working well (56%) and risk to PGY1 well-being (47%). CONCLUSIONS: Although the majority of PDs support the ACGME 2017 work hours rules, only 25% of programs made immediate changes to extend hours. These data reveal that complex, often competing, forces influence PDs' decisions to change trainee schedules.

An upstream open reading frame (uORF) signals for cellular localization of the virulence factor implicated in pregnancy associated malaria.

Plasmodium falciparum, the causative agent of the deadliest form of human malaria, alternates expression of variable antigens, encoded by members of a multi-copy gene family named var. In var2csa, the var gene implicated in pregnancy-associated malaria, translational repression is regulated by a unique upstream open reading frame (uORF) found only in its 5' UTR. Here, we report that this translated uORF significantly alters both transcription and posttranslational protein trafficking. The parasite can alter a protein's destination without any modifications to the protein itself, but instead by an element within the 5' UTR of the transcript. This uORF-dependent localization was confirmed by single molecule STORM imaging, followed by fusion of the uORF to a reporter gene which changes its cellular localization from cytoplasmic to ER-associated. These data point towards a novel regulatory role of uORF in protein trafficking, with important implications for the pathology of pregnancy-associated malaria.