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Cardiac resynchronization therapy (CRT) response is complex, and better approaches are required to predict survival and need for advanced therapies.The objective was to use machine learning to characterize multidimensional CRT response and its relationship with long-term survival.Associations of 39 baseline features (including cardiac magnetic resonance [CMR] findings and clinical parameters such as glomerular filtration rate [GFR]) with a multidimensional CRT response vector (consisting of post-CRT left ventricular end-systolic volume index [LVESVI] fractional change, post-CRT B-type natriuretic peptide, and change in peak VOAmong 200 patients (median age 67.4 years, 27.0% women) with CRT and CMR, associations with more than 1 response parameter were noted for the CMR CURE-SVD dyssynchrony parameter (associated with post-CRT brain natriuretic peptide [BNP] and LVESVI fractional change) and GFR (associated with peak VOMachine learning characterizes distinct CRT response clusters influenced by CMR features, kidney function, and other factors. These clusters have a strong and additive influence on long-term survival relative to baseline features.

BACKGROUND Since early 2016, an increasing number of states passed legislations that limit the duration and/or dosage of initial opioid prescriptions or opioids for acute pain. OBJECTIVE The objective of this study was to assess changes in the number of opioid prescriptions covered by Medicaid and received by Medicaid patients associated with state implementation of legislative limits on initial opioid prescriptions. RESEARCH DESIGN We explored the natural experiment resulting from the staggered implementation of state legislative limits. The analysis adopted a Difference-in-Differences framework and controlled for other major state policies bearing implications for prescription opioid use. The main analysis included 26 states that implemented limits from early 2016 to late 2018. A secondary analysis included all 50 states and the District of Columbia. MEASURES Population-adjusted state-quarter level counts of Schedule II and III opioid prescriptions received by Medicaid patients, based on data from the Medicaid State Drug Utilization Data and state Medicaid enrollment reports for 2013-2018. RESULTS Implementation of legislative limits on initial opioid prescriptions was associated with a 7% reduction in the number of opioid prescriptions per 100 Medicaid enrollees. Such reduction was largely attributable to a reduction in Schedule II opioid prescriptions. Secondary analysis by including all jurisdictions and sensitivity checks supported the robustness of results. CONCLUSION The recent implementation of state legislative limits on initial opioid prescriptions was associated with meaningful reductions in the volume of Schedule II opioid prescriptions received by Medicaid patients.

The cell wall is a crucial structural feature in the vast majority of bacteria and comprises a rigid, covalently closed, mesh-like network of peptidoglycan (PG) strands. While PG synthesis is important for bacterial survival under many conditions, the cell wall is also a dynamic structure, undergoing degradation and remodeling by so-called “autolysins”, enzymes that break bonds in the PG network. Cell division, for example, requires extensive PG remodeling and separation of daughter cells, which depends primarily upon the activity of amidases. However, inV. cholerae, we have found that amidase activity alone is insufficient for daughter cell separation and that the lytic transglycosylases RlpA and MltC both contribute to this process. MltC and RlpA both localize to the septum and are functionally redundant under normal laboratory conditions; however, only RlpA can support normal cell separation in low salt media. The division-specific activity of lytic transglycosylases has implications for the local structure of septal PG, suggesting that there may be glycan bridges between daughter cells that cannot be resolved by amidases. We propose that lytic transglycosylases at the septum serve as a back-up mechanism to cleave rare, stochastically produced PG strands that are crosslinked beyond the reach of the highly spatio-temporally limited activity of the amidase and to clear PG debris that may block the completion of outer-membrane invagination.

Many bacteria are resistant to killing (“tolerant”) by typically bactericidal antibiotics due to their ability to counteract drug-induced cell damage.Vibrio cholerae, the cholera agent, displays an unusually high tolerance to diverse inhibitors of cell wall synthesis. Exposure to these agents, which in other bacteria leads to lysis and death, results in a breakdown of the cell wall and subsequent sphere formation inV. cholerae. Spheres readily recover to rod-shaped cells upon antibiotic removal, but the mechanisms mediating the recovery process are not well-characterized. Here, we found that the mechanisms of recovery are dependent on environmental conditions. Interestingly, on agarose pads, spheres undergo characteristic stages during the restoration of rod shape. Drug inhibition and microscopy experiments suggest that class A Penicillin Binding Proteins (aPBPs) play a more active role than the Rod system, especially early in sphere recovery. TnSeq analyses revealed that LPS and cell wall biogenesis genes as well as the sigma E cell envelope stress response were particularly critical for recovery. LPS core and O-antigen appear to be more critical for sphere formation/integrity and viability than Lipid A modifications. Overall, our findings demonstrate that the outer membrane is a key contributor to beta lactam tolerance and suggest a role for aPBPs in cell wall biogenesis in the absence of rod-shape cues. Factors required for post-antibiotic recovery could serve as targets for antibiotic adjuvants that enhance the efficacy of antibiotics that inhibit cell wall biogenesis.