Socioeconomic Disadvantage Predicts Decreased Likelihood of Maintaining a Functional Knee Arthroplasty Following Treatment for Prosthetic Joint Infection.

BACKGROUND: Prosthetic joint infection (PJI) carries major morbidity and mortality as well as a complicated and lengthy treatment course. In patients who have high degrees of socioeconomic disadvantage, this may be a particularly devastating complication. Our study sought to evaluate the impact of socioeconomic deprivation on outcomes following treatment for PJI of the knee. METHODS: We conducted a retrospective review of revision total knee arthroplasty (TKA) procedures performed for the treatment of initial PJI between 2008 and 2020 at a single tertiary care center in the United States. The Area Deprivation Index (ADI) was used to quantify socioeconomic deprivation. The primary outcome measure was presence of a functional knee joint at the time of most recent follow-up defined as TKA components or an articulating spacer. A total of 96 patients were included for analysis. The median follow-up duration was 26.5 months. RESULTS: There was no significant difference in the rate of treatment failure (P = .63). However, the proportion of patients who had a functional knee arthroplasty (in contrast to having undergone arthrodesis, amputation, or retention of a static spacer) declined significantly with increasing ADI index (81.8% for the least disadvantaged group, 58.7% for the middle group, 42.9% for the most disadvantaged group, P = .021). CONCLUSIONS: Patients who have a higher socioeconomic disadvantage as measured by ADI are less likely to maintain a functional knee arthroplasty following treatment for TKA PJI. These findings support continued efforts to improve access to care and optimize treatment plans for patients who have socioeconomic disadvantage.

Single-Source Precursors for the Controlled Aqueous Synthesis of Bismuth Oxyhalides.

Bismuth oxyhalides are a promising class of photocatalysts for harvesting solar energy. These materials are often synthesized in aqueous media with poor synthetic control resulting from the extremely fast nucleation and growth rates of the particles. These fast rates are caused by the rapid precipitation of bismuth salts with free halide ions. We have developed water-soluble precursors combining bismuth with either chlorine or bromine atoms in the same metal-organic complex. With the application of heat, halide ions are released, which then precipitate with bismuth ions as BiOX (X = Cl, Br). By controlling the halide ion formation rate, the nucleation and growth rates of BiOX materials can be tuned to provide synthetic control. The diverse potential of these precursors is demonstrated by synthesizing BiOX in three ways: aqueous colloidal synthesis, solid-state decomposition, and fabrication of films of BiOX via spray pyrolysis of the aqueous precursor solutions. These broadly applicable single-source precursors will enhance the ability to synthesize future BiOX materials with controlled morphologies.

Mechanochemical Syntheses of Ln(hfac)3(H2O)x (Ln = La-Sm, Tb): Isolation of 10-, 9-, and 8-Coordinate Ln(hfac)n Complexes.

Volatile lanthanide coordination complexes are critical to the generation of new optical and magnetic materials. One of the most common precursors for preparing volatile lanthanide complexes is the hydrate with the general formula Ln(hfac)3(H2O)x (x = 3 for La-Nd, x = 2 for Sm) (hfac = 1,1,1,5,5,5-hexafluoroacetylacetonato). We have investigated the synthesis of Ln(hfac)3(H2O)x using more environmentally sustainable mechanochemical approaches. Characterization of the products using Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, elemental analysis, and powder X-ray diffraction shows substantial differences in product distribution between methods. The mechanochemical synthesis of the hydrate complexes leads to a variety of coordination compounds including the expected hydrate product, the known retro-Claisen impurity, and hydrated protonated Hhfac ligand depending on the technique employed. Surprisingly, 10-coordinate complexes of the form Na2Ln(hfac)5·3H2O for Ln = La-Nd were also isolated from reactions using a mortar and pestle. The electrostatic bonding of lanthanide coordination complexes is a challenge for obtaining reproducible reactions and clean products. The reproducibility issues are most acute for the large, early lanthanides whereas for the mid to late lanthanides, reproducibility in terms of product distribution and yield is less of an issue because of their smaller size and greater charge to radius ratio. Ball milling increases reproducibility in terms of generating the desired Ln(hfac)3(H2O)x along with hydrated Hhfac (tetraol) and free Hhfac products. The results illustrate the dynamic behavior of lanthanide complexes in solution and the solid state as well as the structural diversity available to the early lanthanides.

Quantifying Regional Methane Emissions in the New Mexico Permian Basin with a Comprehensive Aerial Survey.

Limiting emissions of climate-warming methane from oil and gas (O&G) is a major opportunity for short-term climate benefits. We deploy a basin-wide airborne survey of O&G extraction and transportation activities in the New Mexico Permian Basin, spanning 35 923 km2, 26 292 active wells, and over 15 000 km of natural gas pipelines using an independently validated hyperspectral methane point source detection and quantification system. The airborne survey repeatedly visited over 90% of the active wells in the survey region throughout October 2018 to January 2020, totaling approximately 98 000 well site visits. We estimate total O&G methane emissions in this area at 194 (+72/-68, 95% CI) metric tonnes per hour (t/h), or 9.4% (+3.5%/-3.3%) of gross gas production. 50% of observed emissions come from large emission sources with persistence-averaged emission rates over 308 kg/h. The fact that a large sample size is required to characterize the heavy tail of the distribution emphasizes the importance of capturing low-probability, high-consequence events through basin-wide surveys when estimating regional O&G methane emissions.

Adverse Events Associated With Robotic-Assisted Joint Arthroplasty: An Analysis of the US Food and Drug Administration MAUDE Database.

BACKGROUND: The use of robotic assistance in arthroplasty is increasing; however, the spectrum of adverse events potentially associated with this technology is unclear. Improved understanding of the causes of adverse events in robotic-assisted arthroplasty can prevent future incidents and enhance patient outcomes. METHODS: Adverse event reports to the US Food and Drug Administration Manufacturer and User Facility Device Experience database involving robotic-assisted total hip arthroplasty (THA), total knee arthroplasty (TKA), and partial knee arthroplasty were reviewed to determine causes of malfunction and related patient impact. RESULTS: Overall, 263 adverse event reports were included. The most frequently reported adverse events were unexpected robotic arm movement for TKA (59/204, 28.9%) and retained registration checkpoint for THA (19/44, 43.2%). There were 99 reports of surgical delay with an average delay of 20 minutes (range 1-120). Thirty-one cases reported conversion to manual surgery. In total, 68 patient injuries were reported, 7 of which required surgical reintervention. Femoral notching (12/36, 33.3%) was the most common for TKA and retained registration checkpoint (19/28, 67.9%) was the most common for THA. Although rare, additional reported injuries included femoral, tibial, and acetabular fractures, MCL laceration, additional retained foreign bodies, and an electrical burn. CONCLUSION: Despite the increasing utilization of robotic-assisted arthroplasty in the United States, numerous adverse events are possible and technical difficulties experienced intraoperatively can result in prolonged surgical delays. The events reported herein seem to indicate that robotic-assisted arthroplasty is generally safe with only a few reported instances of serious complications, the nature of which seems more related to suboptimal surgical technique than technology. Based on our data, the practice of adding registration checkpoints and bone pins to the instrument count of all robotic-assisted TJA cases should be widely implemented to avoid unintended retained foreign objects.

The role of f0 shape and phrasal position in Papuan Malay and American English word identification.

The prosodic structure of under-researched languages in the Trade Malay language family is poorly understood. Although boundary marking has been uncontroversially shown as the major prosodic function in these languages, studies on the use of pitch accents to highlight important words in a phrase remain inconclusive. In addition, most knowledge of pitch accents is based on well-researched languages such as the ones from the Western-Germanic language family. This paper reports two word identification experiments comparing Papuan Malay with the pitch accent language American English, in order to investigate the extent to which the demarcating and highlighting function of prosody can be disentangled. To this end, target words were presented to native listeners of both languages and differed with respect to their position in the phrase (medial or final) and the shape of their f0 movement (original or manipulated). Reaction times for the target word identifications revealed overall faster responses for original and final words compared to manipulated and medial ones. The results add to previous findings on the facilitating effect of pitch accents and further improve our prosodic knowledge of underresearched languages.

Venoarterial Extracorporeal Membrane Oxygenation in Massive Pulmonary Embolism-Related Cardiac Arrest: A Systematic Review.

OBJECTIVE: Management of patients experiencing massive pulmonary embolism-related cardiac arrest is controversial. Venoarterial extracorporeal membranous oxygenation has emerged as a potential therapeutic option for these patients. We performed a systematic review assessing survival and predictors of mortality in patients with massive PE-related cardiac arrest with venoarterial extracorporeal membranous oxygenation use. DATA SOURCES: A literature search was started on February 16, 2020, and completed on March 16, 2020, using PubMed, Embase, Cochrane Central, Cinahl, and Web of Science. STUDY SELECTION: We included all available literature that reported survival to discharge in patients managed with venoarterial extracorporeal membranous oxygenation for massive PE-related cardiac arrest. DATA EXTRACTION: We extracted patient characteristics, treatment details, and outcomes. DATA SYNTHESIS: About 301 patients were included in our systemic review from 77 selected articles (total screened, n = 1,115). About 183 out of 301 patients (61%) survived to discharge. Patients (n = 51) who received systemic thrombolysis prior to cannulation had similar survival compared with patients who did not (67% vs 61%, respectively; p = 0.48). There was no significant difference in risk of death if PE was the primary reason for admission or not (odds ratio, 1.62; p = 0.35) and if extracorporeal membranous oxygenation cannulation occurred in the emergency department versus other hospital locations (odds ratio, 2.52; p = 0.16). About 53 of 60 patients (88%) were neurologically intact at discharge or follow-up. Multivariate analysis demonstrated three-fold increase in the risk of death for patients greater than 65 years old (adjusted odds ratio, 3.08; p = 0.03) and six-fold increase if cannulation occurred during cardiopulmonary resuscitation (adjusted odds ratio, 5.67; p = 0.03). CONCLUSIONS: Venoarterial extracorporeal membranous oxygenation has an emerging role in the management of massive PE-related cardiac arrest with 61% survival. Systemic thrombolysis preceding venoarterial extracorporeal membranous oxygenation did not confer a statistically significant increase in risk of death, yet age greater than 65 and cannulation during cardiopulmonary resuscitation were associated with a three- and six-fold risks of death, respectively.

Organohalide Precursors for the Continuous Production of Photocatalytic Bismuth Oxyhalide Nanoplates.

Metal heteroanionic materials, such as oxyhalides, are promising photocatalysts in which band positions can be engineered for visible-light absorption by changing the halide identity. Advancing the synthesis of these materials, bismuth oxyhalides of the form BiOX (X = Cl, Br) have been prepared using rapid and scalable ultrasonic spray synthesis (USS). Central to this advance was the identification of small organohalide molecules as halide sources. When these precursors are spatially and temporally confined in the aerosol phase with molten salt fluxes, powders composed of single-crystalline BiOX nanoplates can be produced continuously. A mechanism highlighting the in situ generation of halide ions is proposed. These materials can be used as photocatalysts and provide proof-of-concept toward USS as a route to more complex bismuth oxyhalide materials.

Uncoupling High Light Responses from Singlet Oxygen Retrograde Signaling and Spatial-Temporal Systemic Acquired Acclimation.

Distinct ROS signaling pathways initiated by singlet oxygen ((1)O2) or superoxide and hydrogen peroxide have been attributed to either cell death or acclimation, respectively. Recent studies have revealed that more complex antagonistic and synergistic relationships exist within and between these pathways. As specific chloroplastic ROS signals are difficult to study, rapid systemic signaling experiments using localized high light (HL) stress or ROS treatments were used in this study to uncouple signals required for direct HL and ROS perception and distal systemic acquired acclimation (SAA). A qPCR approach was chosen to determine local perception and distal signal reception. Analysis of a thylakoidal ascorbate peroxidase mutant (tapx), the (1)O2-retrograde signaling double mutant (ex1/ex2), and an apoplastic signaling double mutant (rbohD/F) revealed that tAPX and EXECUTER 1 are required for both HL and systemic acclimation stress perception. Apoplastic membrane-localized RBOHs were required for systemic spread of the signal but not for local signal induction in directly stressed tissues. Endogenous ROS treatments revealed a very strong systemic response induced by a localized 1 h induction of (1)O2 using the conditional flu mutant. A qPCR time course of (1)O2 induced systemic marker genes in directly and indirectly connected leaves revealed a direct vascular connection component of both immediate and longer term SAA signaling responses. These results reveal the importance of an EXECUTER-dependent (1)O2 retrograde signal for both local and long distance RBOH-dependent acclimation signaling that is distinct from other HL signaling pathways, and that direct vascular connections have a role in spatial-temporal SAA induction.

Investigation of Cost and Energy Optimization of Drinking Water Distribution Systems.

Holistic management of water and energy resources through energy and water quality management systems (EWQMSs) have traditionally aimed at energy cost reduction with limited or no emphasis on energy efficiency or greenhouse gas minimization. This study expanded the existing EWQMS framework and determined the impact of different management strategies for energy cost and energy consumption (e.g., carbon footprint) reduction on system performance at two drinking water utilities in California (United States). The results showed that optimizing for cost led to cost reductions of 4% (Utility B, summer) to 48% (Utility A, winter). The energy optimization strategy was successfully able to find the lowest energy use operation and achieved energy usage reductions of 3% (Utility B, summer) to 10% (Utility A, winter). The findings of this study revealed that there may be a trade-off between cost optimization (dollars) and energy use (kilowatt-hours), particularly in the summer, when optimizing the system for the reduction of energy use to a minimum incurred cost increases of 64% and 184% compared with the cost optimization scenario. Water age simulations through hydraulic modeling did not reveal any adverse effects on the water quality in the distribution system or in tanks from pump schedule optimization targeting either cost or energy minimization.

Observational studies generate misleading results about the health effects of air pollution: Evidence from chronic air pollution and COVID-19 outcomes.

Several observational studies from locations around the globe have documented a positive correlation between air pollution and the severity of COVID-19 disease. Observational studies cannot identify the causal link between air quality and the severity of COVID-19 outcomes, and these studies face three key identification challenges: 1) air pollution is not randomly distributed across geographies; 2) air-quality monitoring networks are sparse spatially; and 3) defensive behaviors to mediate exposure to air pollution and COVID-19 are not equally available to all, leading to large measurement error bias when using rate-based COVID-19 outcome measures (e.g., incidence rate or mortality rate). Using a quasi-experimental design, we explore whether traffic-related air pollutants cause people with COVID-19 to suffer more extreme health outcomes in New York City (NYC). When we address the previously overlooked challenges to identification, we do not detect causal impacts of increased chronic concentrations of traffic-related air pollutants on COVID-19 death or hospitalization counts in NYC census tracts.

Comparing DNA isolation and sequencing strategies for 16S rRNA gene amplicon analysis in biofilm containing environments.

Bacteria are primarily responsible for biological water treatment processes in constructed wetland systems. Gravel in constructed wetlands serves as an essential substrate onto which complex bacterial biofilms may successfully grow and evolve. To fully understand the bacterial community in these systems it is crucial to properly isolate biofilms and process DNA from such substrates. This study looked at how best to isolate bacterial biofilms from gravel substrates in terms of bacterial richness. It considered factors including the duration of agitation during extraction, extraction temperature, and enzyme usage. Further, the 16S taxonomy data subsequently produced from Illumina MiSeq reads (using the SILVA 132 ribosomal RNA (rRNA) database on the DADA2 pipeline) were compared with the 16S data produced from Oxford Nanopore Technologies (ONT) MinION reads (using the NCBI 16S database on the EPI2ME pipeline). Finally, performance was tested by comparing the taxonomy data generated from the Illumina MiSeq and ONT MinION reads using the same (SILVA 132) database. We found no significant differences in the effective number of species observed when using different bacterial biofilm detachment techniques. However, enzyme treatment enhanced the total concentration of DNA. In terms of wetland community profiles, relative abundance differences within each sample type were clearer at the genus level. For genus-level taxonomic classification, MinION sequencing with the EPI2ME pipeline (NCBI database) produced bacterial abundance information that was poorly correlated with that from the Illumina MiSeq and DADA2 pipelines (SILVA132 database). When using the same database for each sequencing technology (SILVA132), the correlation between relative abundances at genus-level improved from negligible to moderate. This study provides detailed information of value to researchers working on constructed wetlands regarding efficient biofilm detachment techniques for DNA isolation and 16 s metabarcoding platforms for sequencing and data analysis.

Critical Care Management of Severe Asthma Exacerbations.

Severe asthma exacerbations, including near-fatal asthma (NFA), have high morbidity and mortality. Mechanical ventilation of patients with severe asthma is difficult due to the complex pathophysiology resulting from severe bronchospasm and dynamic hyperinflation. Life-threatening complications of traditional ventilation strategies in asthma exacerbations include the development of systemic hypotension from hyperinflation, air trapping, and pneumothoraces. Optimizing pharmacologic techniques and ventilation strategies is crucial to treat the underlying bronchospasm. Despite optimal pharmacologic management and mechanical ventilation, the mortality rate of patients with severe asthma in intensive care units is 8%, suggesting a need for advanced non-pharmacologic therapies, including extracorporeal life support (ECLS). This review focuses on the pathophysiology of acute asthma exacerbations, ventilation management including non-invasive ventilation (NIV) and invasive mechanical ventilation (IMV), the pharmacologic management of acute asthma, and ECLS. This review also explores additional advanced non-pharmacologic techniques and monitoring tools for the safe and effective management of critically ill adult asthmatic patients.

Single-institution experience of extracorporeal membrane oxygenation for near-fatal asthma.

Near-fatal asthma (NFA) is the most severe presentation of asthma. It is characterized by hypoxemic and hypercapnic respiratory failure requiring ventilatory assistance, including non-invasive ventilation and mechanical ventilation. However, NFA has a high mortality rate despite conventional therapy. Extracorporeal membrane oxygenation (ECMO) is a treatment modality that is increasingly being utilized as rescue therapy in patients with NFA that is refractory to mechanical ventilation. Prior analyses of the international Extracorporeal Life Support Organization (ELSO) registry data showed a survival rate of over 83% in patients placed on venovenous (VV) ECMO for NFA, but with notable rate of hemorrhagic complications. We report seven cases of adults with NFA requiring ECMO support at our large quaternary care institution between the years 2019 and 2022. All seven patients presented with respiratory failure in the setting of asthma exacerbation that progressed despite standard pharmacotherapy and mechanical ventilation. All patients survived to hospital discharge after ECMO support without hemorrhagic complications, highlighting the effectiveness and safety of ECMO when appropriately used in this population.

The Reverse Fragility Index: Interpreting the Current Literature on Long-Term Survivorship of Computer-Navigated Versus Conventional TKA: A Systematic Review and Cross-Sectional Study of Randomized Controlled Trials.

BACKGROUND: Despite the most recent American Academy of Orthopaedic Surgeons clinical practice guideline making a "strong" recommendation against the use of intraoperative navigation in total knee arthroplasty (TKA), its use is increasing. We utilized the concept of the reverse fragility index (RFI) to assess the strength of neutrality of the randomized controlled trials (RCTs) comparing the long-term survivorship of computer-navigated and conventional TKA. METHODS: A systematic review was performed including all RCTs through August 3, 2021, comparing the long-term outcomes of computer-navigated and conventional TKA. Randomized trials with mean follow-up of >8 years and survivorship with revision as the end point were included. The RFI quantifies the strength of a study's neutrality by calculating the minimum number of events necessary to flip the result from nonsignificant to significant. The RFI at a threshold of p < 0.05 was calculated for each study reporting nonsignificant results. The reverse fragility quotient (RFQ) was calculated by dividing the RFI by the study sample size. RESULTS: Ten clinical trials with 2,518 patients and 38 all-cause revisions were analyzed. All 10 studies reported nonsignificant results. The median RFI at the p < 0.05 threshold was 4, meaning that a median of 4 events would be needed to change the results from nonsignificant to significant. The median RFQ was 0.029, indicating that the nonsignificance of the results was contingent on only 2.9 events per 100 participants. The median loss to follow-up was 27 patients. In all studies, the number of patients lost to follow-up was greater than the RFI. CONCLUSIONS: The equipoise in long-term survivorship between computer-navigated and conventional TKA rests on fragile studies, as their statistical nonsignificance could be reversed by changing the outcome status of only a handful of patients--a number that was always smaller than the number lost to follow-up. Routine reporting of the RFI in trials with nonsignificant findings may provide readers with a measure of confidence in the neutrality of the results. LEVEL OF EVIDENCE: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Minimally Invasive Diaphragm Plication for Acquired Unilateral Diaphragm Paralysis: A Systematic Review.

Objective: Diaphragm paralysis is a relatively uncommon entity that can be both congenital and acquired in nature. While commonly asymptomatic, it can also cause a significant decrease in pulmonary function and reserve, particularly in patients with underlying pulmonary diseases. Our aim was to summarize the current literature regarding the minimally invasive techniques used in the surgical correction of acquired diaphragm paralysis via traditional and robotic minimally invasive approaches. Methods: We conducted a systematic review of available literature using the Cochrane methodology and reported findings according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) standards. Results: A total of 6,561 citations were identified through initial database and reference searches, of which 90 articles met the inclusion criteria for review. After further assessment, 33 appropriate full-text studies were selected for the review. Of the selected publications, the majority represented case reports and single-center retrospective studies with level of evidence 4. Only 1 level 2b study (individual cohort study) was identified, comparing minimally invasive and open approaches. Conclusions: Each of the minimally invasive approaches has its unique benefits and disadvantages, which are summarized and delineated in this article. Ultimately, no preferred method of diaphragm plication for diaphragm paralysis can be recommended at this time based on clinical data. The choice of procedure and surgical approach continues to be selected based on the surgeon's experience and preference.

Crystal structures of three ß-halolactic acids: hydrogen bonding resulting in differing Z'.

The crystal structures of three ß-halolactic acids have been determined, namely, ß-chlorolactic acid (systematic name: 3-chloro-2-hydroxypropanoic acid, C3H5ClO3) (I), ß-bromolactic acid (systematic name: 3-bromo-2-hydroxypropanoic acid, C3H5BrO3) (II), and ß-iodolactic acid (systematic name: 2-hydroxy-3-iodopropanoic acid, C3H5IO3) (III). The number of molecules in the asymmetric unit of each crystal structure (Z') was found to be two for I and II, and one for III, making I and II isostructural and III unique. The difference between the molecules in the asymmetric units of I and II is due to the direction of the hydrogen bond of the alcohol group to a neighboring molecule. Molecular packing shows that each structure has alternating layers of intermolecular hydrogen bonding and halogen-halogen interactions. Hirshfeld surfaces and two-dimensional fingerprint plots were analyzed to further explore the intermolecular interactions of these structures. In I and II, energy minimization is achieved by lowering of the symmetry to adopt two independent molecular conformations in the asymmetric unit.

Field monitoring the seasonal variation in Albatrellus ellisii mycelium abundance with a species-specific genetic marker.

The conservation of rare fungal sites occurring on actively managed forest lands requires efficient site monitoring methods. In this study species-specific primers for the putatively mycorrhizal Albatrellus ellisii (Russulales) were developed so that DNA extracted from soil samples at known sites of this fungus could be tested for the presence of A. ellisii mycelium with PCR. This method was used to measure seasonal changes in the levels of A. ellisii mycelium at three study sites while the utility of this monitoring method was assessed. We found that A. ellisii maintained a constant level of soil occupancy over three seasons, except at one site where mycelium abundance increased in the fall. No reduction in abundance was seen in the summer, although all three sites experienced significant summer drought. We found species-specific genetic marker detection to be an effective and practical method for monitoring the mycelial distribution of a target fungus in soil. The ability to obtain this data from rare fungal sites advances our capability to conserve these fungi, particularly within the managed forest landscape.

Mapping the biosynthetic pathway of a hybrid polyketide-nonribosomal peptide in a metazoan.

Polyketide synthase (PKS) and nonribosomal peptide synthetase (NRPS) hybrid systems typically use complex protein-protein interactions to facilitate direct transfer of intermediates between these multimodular megaenzymes. In the canal-associated neurons (CANs) of Caenorhabditis elegans, PKS-1 and NRPS-1 produce the nemamides, the only known hybrid polyketide-nonribosomal peptides biosynthesized by animals, through a poorly understood mechanism. Here, we use genome editing and mass spectrometry to map the roles of individual PKS-1 and NRPS-1 enzymatic domains in nemamide biosynthesis. Furthermore, we show that nemamide biosynthesis requires at least five additional enzymes expressed in the CANs that are encoded by genes distributed across the worm genome. We identify the roles of these enzymes and discover a mechanism for trafficking intermediates between a PKS and an NRPS. Specifically, the enzyme PKAL-1 activates an advanced polyketide intermediate as an adenylate and directly loads it onto a carrier protein in NRPS-1. This trafficking mechanism provides a means by which a PKS-NRPS system can expand its biosynthetic potential and is likely important for the regulation of nemamide biosynthesis.

Differences in Hospital Costs among Octogenarians and Nonagenarians Following Primary Total Joint Arthroplasty.

The proportion of patients over the age of 90 years continues to grow, and the anticipated demand for total joint arthroplasty (TJA) in this population is expected to rise concomitantly. As the country shifts to alternative reimbursement models, data regarding hospital expenses is needed for accurate risk-adjusted stratification. The aim of this study was to compare total in-hospital costs following primary TJA in octogenarians and nonagenarians, and to determine the primary drivers of cost. This was a retrospective analysis from a single institution in the U.S. We used time-drive activity-based costing (TDABC) to capture granular total hospital costs for each patient. 889 TJA's were included in the study, with 841 octogenarians and 48 nonagenarians. Nonagenarians were more likely to undergo total hip arthroplasty (THA) (70.8% vs. 42.4%; p < 0.0001), had higher ASA classification (2.6 vs. 2.4; p = 0.049), and were more often privately insured (35.4% vs. 27.8%; p = 0.0001) as compared to octogenarians. Nonagenarians were more often discharged to skilled nursing facilities (56.2% vs. 37.5%; p = 0.0011), experienced longer operating room (OR) time (142 vs. 133; p = 0.0201) and length of stay (3.7 vs. 3.1; p = 0.0003), and had higher implant and total in-hospital costs (p < 0.0001 and 0.0001). Multivariate linear regression showed implant cost (0.700; p < 0.0001), length of stay (0.546; p < 0.0001), and OR time (0.288; p < 0.0001) to be the strongest associations with overall costs. Primary TJA for nonagenarians was more expensive than octogenarians. Targeting implant costs, length of stay, and OR time can reduce costs for nonagenarians in order to provide cost-effective value-based care.