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The synthesis and characterisation of a series of new actinide(IV) complexes supported by the mixed-donor amido-amino-siloxo framework [RN(Li)SiMe2N(R)SiMe2OLi] ([RNNO]Li2; R = 2,4,6-Me3Ph, 2,6- iPr2Ph) are presented. The reaction of 1 equiv. of [RNNO]Li2 with ThCl4 ·2DME (DME = 1,2-dimethoxyethane) in DME generated {Li · nDME}{[RNNO]2Th2Cl5} ( 1: R = 2,4,6-Me3Ph, n = 2; 2: R = 2,6- iPr2Ph, n = 3) in high yield, and the addition of [ [ABSTRACT FROM AUTHOR]

This article describes a case of an infected total hip arthroplasty following a dental procedure. A 59-year-old man underwent total hip arthroplasty for osteoarthritis and had a routine recovery. Approximately 9 months postoperatively, he underwent a dental cleaning without antibiotic prophylaxis. One month later, he reported gradually worsening right hip pain and a purulent discharge. After several unsuccessful interventions, the patient was referred to the authors' facility. The patient's history, draining sinus tract, and radiographic changes were considered diagnostic of a late chronic infection, and the patient underwent 2-stage revision. Intraoperatively, the sinus tract extended directly to the acetabular component. This article describes a case of an infected total hip arthroplasty following a dental procedure. A 59-year-old man underwent total hip arthroplasty for osteoarthritis and had a routine recovery. Approximately 9 months postoperatively, he underwent a dental cleaning without antibiotic prophylaxis. One month later, he reported gradually worsening right hip pain and a purulent discharge. After several unsuccessful interventions, the patient was referred to the authors' facility. The patient's history, draining sinus tract, and radiographic changes were considered diagnostic of a late chronic infection, and the patient underwent 2-stage revision. Intraoperatively, the sinus tract extended directly to the acetabular component. Actinomyces spp were isolated from 3 of 7 intraoperative anaerobic cultures, and the patient received penicillin G for 8 weeks. Two weeks after discontinuing antibiotics, with no clinical manifestation of recurrent infection and a negative hip aspiration, a new hip prosthesis was implanted. The patient was prescribed penicillin for 12 months postoperatively. Harris Hip Score was 100 at 52-month follow-up. The American Dental Association and the American Academy of Orthopaedic Surgeons issued consensus guidelines for chemoprophylaxis in orthopedic patients undergoing dental procedures in 1997 and 2003. Although the American Academy of Orthopaedic Surgeons issued a revised guideline in 2009 recommending more robust antibiotic prophylaxis, significant controversy exists because at least one professional organization representing dentists has repudiated the 2009 American Academy of Orthopaedic Surgeons guideline. The authors describe the implications from their experience and similar cases in the literature with regard to such guidelines. [ABSTRACT FROM AUTHOR]

The Armed Forces Health Surveillance Center's Division of Global Emerging Infections Surveillance and Response System (AFHSC-GEIS) supports and oversees surveillance for emerging infectious diseases, including respiratory diseases, of importance to the U.S. Department of Defense (DoD). AFHSC-GEIS accomplishes this mission by providing funding and oversight to a global network of partners for respiratory disease surveillance. This report details the system's surveillance activities during 2009, with a focus on efforts in responding to the novel H1N1 Influenza A (A/H1N1) pandemic and contributions to global public health. Active surveillance networks established by AFHSC-GEIS partners resulted in the initial detection of novel A/H1N1 influenza in the U.S. and several other countries, and viruses isolated from these activities were used as seed strains for the 2009 pandemic influenza vaccine. Partners also provided diagnostic laboratory training and capacity building to host nations to assist with the novel A/H1N1 pandemic global response, adapted a Food and Drug Administration-approved assay for use on a ruggedized polymerase chain reaction platform for diagnosing novel A/H1N1 in remote settings, and provided estimates of seasonal vaccine effectiveness against novel A/H1N1 illness. Regular reporting of the system's worldwide surveillance findings to the global public health community enabled leaders to make informed decisions on disease mitigation measures and controls for the 2009 A/H1N1 influenza pandemic. AFHSC-GEIS's support of a global network contributes to DoD's force health protection, while supporting global public health. [ABSTRACT FROM AUTHOR]

FFLUX is a next-generation, machine-learnt force field built on three cornerstones: quantum chemical topology, Gaussian process regression, and (high-rank) multipolar electrostatics. It is capable of performing molecular dynamics with near-quantum accuracy at a lower computational cost than standard ab initio molecular dynamics. Previous work with FFLUX was concerned with water and formamide. In this study, we go one step further and challenge FFLUX to model urea, a larger and more flexible system. In result, we have trained urea models at the B3LYP/aug-cc-pVTZ level of theory, with a mean absolute error of 0.4 kJ mol -1 and a maximum prediction error below 7.0 kJ mol -1 . To test their performance in molecular dynamics simulations, two sets of FFLUX geometry optimizations were carried out: 5 dimers corresponding to energy minima and 75 random dimers. The 5 dimers were recovered with a root-mean-square deviation below 0.1 Å with respect to their ab initio references. Out of the 75 random dimers, 68% converged to the qualitatively same dimer as those obtained at the ab initio level. Furthermore, we have ranked the 5 FFLUX-optimized dimers in the order of their relative FFLUX single-point energies and compared them with the ab initio method. The energy ranking fully agreed but for one crossover between two successive minima. Finally, we have demonstrated the importance of geometry-dependent ( i . e ., flexible) multipole moments, showing that the lack of multipole moment flexibility can lead to average errors in the total intermolecular electrostatic energy of more than 2 orders of magnitude.

FFLUX is a quantum chemical topology-based multipolar force field that uses Gaussian process regression machine learning models to predict atomic energies and multipole moments on the fly for fast and accurate molecular dynamics simulations. These models have previously been trained on monomers, meaning that many-body effects, for example, intermolecular charge transfer, are missed in simulations. Moreover, dispersion and repulsion have been modeled using Lennard-Jones potentials, necessitating careful parametrization. In this work, we take an important step toward addressing these shortcomings and show that models trained on clusters, in this case, a dimer, can be used in FFLUX simulations by preparing and benchmarking a formamide dimer model. To mitigate the computational costs associated with training higher-dimensional models, we rely on the transfer of hyperparameters from a smaller source model to a larger target model, enabling an order of magnitude faster training than with a direct learning approach. The dimer model allows for simulations that account for two-body effects, including intermolecular polarization and charge penetration, and that do not require nonbonded potentials. We show that addressing these limitations allows for simulations that are closer to quantum mechanics than previously possible with the monomeric models.

The repulsive part of the Buckingham potential, with parameters A and B , can be used to model deformation energies and steric energies. Both are calculated using the interacting quantum atom energy decomposition scheme where the latter is obtained from the former by a charge-transfer-based energy correction. These energies relate to short-range interactions, specifically the deformation of electron density and steric hindrance, respectively, when topological atoms approach each other. In this work, we calculate and fit the energies of carbonyl carbon, carbonyl oxygen, and, where possible, amine nitrogen atoms to the repulsive part of the Buckingham potential for 26 molecules. We find that while the steric energies of all atom pairs studied display exponential behavior with respect to distance, some deformation energy data do not. The obtained parameters are shown to be transferable by calculating root-mean-square errors of fitted potentials with respect to energy data of the same atom in, as far as possible, all other molecules from our data set. We observed that 36% and 10% of these errors were smaller than 4 kJ mol -1 for steric and deformation energy, respectively. Thus, we find that steric energy parameters are more transferable than deformation energy parameters. Finally, we speculate about the physical meaning of the A and B parameters and the implications of the strong exponential and exponential-linear piecewise relationships that we observe between them.

Background: How socio-demographic characteristics and comorbidities affect bacterial community-acquired pneumonia (CAP) prognosis during/after hospitalization is important in disease management., Objectives: To identify predictors of medical intensive care unit (MICU) admission, length of hospital stay (LOS), in-hospital mortality, and bacterial CAP readmission in patients hospitalized with bacterial CAP., Methods: ICD-9/10 codes were used to query electronic medical records to identify a cohort of patients hospitalized for bacterial CAP at a tertiary hospital in Southeastern US between 01/01/2013-12/31/2019. Adjusted accelerated failure time and modified Poisson regression models were used to examine predictors of MICU admission, LOS, in-hospital mortality, and 1-year readmission., Results: There were 1956 adults hospitalized with bacterial CAP. Median (interquartile range) LOS was 11 days (6-23), and there were 26 % (513) MICU admission, 14 % (266) in-hospital mortality, and 6 % (117) 1-year readmission with recurrent CAP. MICU admission was associated with heart failure (RR 1.38; 95 % CI 1.17-1.62) and obesity (RR 1.26; 95 % CI 1.04-1.52). Longer LOS was associated with heart failure (adjusted time ratio[TR] 1.27;95 %CI 1.12-1.43), stroke (TR 1.90;95 %CI 1.54,2.35), type 2 diabetes (TR 1.20;95 %CI 1.07-1.36), obesity (TR 1.50;95 %CI 1.31-1.72), Black race (TR 1.17;95 %CI 1.04-1.31), and males (TR 1.24;95 %CI 1.10-1.39). In-hospital mortality was associated with stroke (RR 1.45;95 %CI 1.03-2.04) and age ≥65 years (RR 1.34;95 %CI 1.06-1.68). 1-year readmission was associated with COPD (RR 1.55;95 %CI 1.05-2.27) and underweight BMI (RR 1.74;95 %CI 1.04-2.90)., Conclusions: Comorbidities and socio-demographic characteristics have varying impacts on bacterial CAP in-hospital prognosis and readmission. More studies are warranted to confirm these findings to develop comprehensive care plans and inform public health interventions., Competing Interests: Declaration of competing interest No conflicts exist for AJI, MLB, HWW, RLG, SS, and RAL., (Published by Elsevier Inc.)

Background: Acute kidney injury (AKI) is associated with increased complications after total hip arthroplasty (THA) and total knee arthroplasty (TKA). The purpose of this study was to determine the risk factors for AKI after THA and TKA and evaluate if preoperative use of antihypertensive drugs is a risk factor for AKI., Methods: A retrospective review of 7406 primary TKAs and THAs (4532 hips and 2874 knees) from 2013 to 2019 was performed. The following preoperative variables were obtained from medical records: medications, chemistry 7 panel, Elixhauser comorbidities, and demographic factors. AKI was defined as an increase in serum creatinine by 26.4 μmol·L-1. Multivariate analysis was performed to identify the risk factors., Results: The overall incidence of postoperative AKI was 6.2% (n = 459). Risk factors for postoperative AKI were found to be: chronic kidney disease (odds ratio [OR] = 7.09; 95% confidence interval [CI]: 4.8-9.4), diabetes (OR: 5.03; 95% CI: 2.8-6.06), ≥3 antihypertensive drugs (OR: 4.2; 95% CI: 2.1-6.2), preoperative use of an angiotensin receptor blockers or angiotensin-converting enzyme inhibitors (OR: 3.8; 95% CI: 2.2-5.9), perioperative vancomycin (OR: 2.7; 95% CI: 1.8-4.6), and body mass index >40 kg/m 2 (OR: 1.9; 95% CI: 1.3-3.06)., Conclusions: We have identified several modifiable risk factors for AKI that can be optimized prior to an elective THA or TKA. The use of certain antihypertensive agents namely angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and multidrug antihypertensive regimens were found to significantly increase the risk of AKI. Therefore, perioperative management of patients undergoing joint replacement should include medical comanagement with a focus on careful management of antihypertensives., (© 2024 The Authors.)

Arthrofibrosis is a multifactorial process that results in decreased knee range of motion (ROM). Manipulation under anesthesia (MUA) is commonly regarded as the preferred initial treatment of arthrofibrosis following total knee arthroplasty (TKA). There have been no well-controlled studies demonstrating that MUA effectively increases ROM in patients who develop arthrofibrosis after TKA when compared with routine care. The purpose of this study was to determine whether MUA had any advantage over routine care in the treatment of patients who developed arthrofibrosis following TKA. The authors identified patients who underwent primary TKA at the authors' institution between 2010 and 2014 and had flexion ≤ 100 degrees at early follow-up. Knees were grouped based on how the arthrofibrosis was treated: those who underwent MUA and those who received routine care. Knee flexion was captured preoperatively (prior to TKA), at early follow-up (prior to MUA or routine care), and at 1-year follow up. Flexion change from early follow-up to 1 year was calculated. The average flexion at 1-year follow-up was not significantly different between the two groups (106.1 ± 11.7 degrees in the routine care group versus 106.3 ± 12.8 degrees in the MUA group). The MUA group had a greater proportion of patients with flexion gains > 20 degrees at final follow-up when compared with patients who underwent routine care (56% vs. 8%, p < 0.0001). This study demonstrates that patients with decreased ROM at early follow-up after primary TKA can expect greater ROM increase at 1-year follow-up if they undergo MUA compared with patients who undergo routine care. (Journal of Surgical Orthopaedic Advances 33(1):033-036, 2024).

Purpose: This study aimed to investigate the complications of primary total hip arthroplasty based on immediate postoperative X-rays. The overall quality and cost of X-rays were assessed., Methods: The institutional database was queried to identify all patients who underwent total hip arthroplasty in a single institution between January 1, 2018, and December 31, 2018. Immediate postoperative X-rays were reviewed to identify the complications such as periprosthetic fractures, dislocation, and fixation failure. The quality and cost of X-ray were assessed. The complications were categorized as "known" and "unknown" according to the intraoperative fluoroscopic results., Results: A total of 518 total hip arthroplasties were included in this study. Based on intraoperative fluoroscopy, periprosthetic fractures were found in 10 (2%) THAs. Compared to the X-rays taken immediately after surgery, 9 periprosthetic fractures (recorded as "known") were found and 1 was not (recorded as "unknown"). There was no significant difference between intraoperative fluoroscopy and X-rays (P > 0.05). Of the 518 X-rays, 225 (43%) were of suboptimal quality. The cost of a single portable pelvic X-ray was $647., Conclusion: In total hip arthroplasty, X-rays taken immediately after surgery rarely reveal unknown complications. The X-rays are often of suboptimal quality, have minimal clinical utility, and are less cost-effective., (© 2022. The Author(s).)

Background: The number of total knee arthroplasties (TKA) performed in the United States is projected to rise significantly, with a proportionate increase in the revision burden. Understanding the mechanism of failure in primary TKA is important as etiologies continue to evolve and reasons for revision change. The purpose of this study was to determine the reason for revision TKA at our institution among early and late failures and assess if the etiology has changed over a 10-year time-period., Methods: We identified 258 revision TKAs performed at our institution between 2005 and 2014. Reasons for revision TKA were categorized according to diagnosis. We also conducted subgroup analysis for TKA revisions performed within two years of the primary TKA (early failures) and those performed after two years (late failures). Revision TKAs were also grouped by year of primary TKA (before and after 2000) and time period in which the revision TKA was performed (2005-2009 and 2010-2014)., Results: The most common reason for revision TKA was infection (29.3%), followed by aseptic loosening (19.7%), which together accounted for half of all revisions. Other indications for revision were instability (11.6%), osteolysis (10.4%), arthrofibrosis (8.1%), polyethylene (PE) wear (7.7%), malalignment/malposition (5.4%), patellar complication (3.1%), periprosthetic fracture (2.3%), pain (1.5%), and extensor mechanism deficiency (0.8%). Nearly half of early failures (47%) were due to infection. Osteolysis and PE wear made of a significantly higher proportion of revisions of TKAs performed prior to 2000 compared to index TKAs performed after 2000., Conclusion: At our institution, infection was the most common reason for revision TKA. Infection had a higher rate of early revisions. Proportion of TKAs revised for osteolysis and PE wear was higher for TKAs performed prior to 2000. Proportion of revision TKA for infection and instability were higher with TKAs performed after 2000., (© 2022. The Author(s).)

Background: Microbial etiology for community-acquired pneumonia (CAP) is evolving with pathogens known for high CAP mortality e.g., Pseudomonas species. Chronic obstructive pulmonary disease (COPD) patients are at risk for hospitalization for CAP. Understanding regional patterns and risk factors for multidrug-resistant (MDR) Pseudomonas acquisition has implications for antimicrobial stewardship., Objectives: To evaluate the regional epidemiology of MDR Pseudomonas CAP and its association with COPD., Methods: We queried the electronic medical records of the University of Alabama at Birmingham Healthcare System to identify patients hospitalized for CAP with Pseudomonas positive respiratory samples between 01/01/2013-12/31/2019. Log binomial regression models were used to examine associations between COPD diagnosis and risk of Pseudomonas/MDR Pseudomonas CAP., Results: Cohort consisted of 913 culture positive CAP cases aged 59-year (IQR:48-68), 61% (560) male, 60% (547) white, 65% (580) current/past smokers, and 42% (384) COPD. Prevalence of Pseudomonas CAP in culture positive CAP was 18% (167), MDR Pseudomonas CAP in Pseudomonas CAP was 22% (36), and yearly incidence of MDR Pseudomonas CAP was stable (p = 0.169). COPD was associated with Pseudomonas CAP (RR 1.39; 95% CI 1.01, 1.91; p = 0.041) but not with MDR Pseudomonas CAP (0.71; 95% CI 0.35, 1.45; p = 0.349). Stroke (RR 2.64; 95% CI 1.51, 4.61; p = 0.0006) and use of supplemental oxygen (RR 2.31; 95% CI 1.30, 4.12; p = 0.005) were associated with MDR Pseudomonas CAP., Conclusion: Incidence of MDR Pseudomonas CAP was stable over time. COPD was associated with Pseudomonas CAP but not with MDR Pseudomonas CAP. Larger cohort studies are needed to confirm findings., (© 2022. The Author(s).)

Although the vast majority of arthroplasty surgeons allow patients to return to participation in golf following total knee arthroplasty (TKA) and total hip arthroplasty (THA), there is relatively little published data regarding how TKA or THA affects a patient's golfing ability. The purpose of this study was to determine how golfers' handicaps change following TKA and THA. We mailed a questionnaire to patients who had underwent primary TKA or THA at our institution and asked whether they played golf and for their golf handicap information network (GHIN) number. We then obtained handicap data for each patient that provided a GHIN number. Handicap increased 0.9 strokes 1 year following THA; however, this difference was not statistically significant (p = 0.20). Handicap increased 0.3 strokes 1 year following TKA; however, this difference was not statistically significant (p = 0.29). Our study demonstrates that despite improved implants, surgical techniques, and rehabilitation protocols that golf handicap does not change significantly following lower extremity total joint arthroplasty (TJA). (Journal of Surgical Orthopaedic Advances 29(4):216-218, 2020).

Significant debate persists about posterior cruciate-retaining (CR) versus posterior cruciate-substituting (PS) implant design for total knee arthroplasty (TKA). This study sought to test the hypothesis that CR TKA will facilitate improved early functional outcomes in gait compared with PS TKA. Patients were randomized to either the CR or PS implant. Various patient-reported and surgeon-reported outcomes as well as gait analyses were obtained pre- and postoperatively. Patients undergoing PS TKA had higher University of California, Los Angeles activity scores at 12 months. No significant difference in spatiotemporal, kinematic, or kinetic parameters between groups was detected, but there was a trend toward quadriceps overuse gait pattern in the CR group. Patients undergoing TKA with a PS implant were more willing to engage in regular higher level physical activity. The CR implant may be a risk factor for quadriceps overuse gait pattern, while the PS implant may be protective against quadriceps overuse. (Journal of Surgical Orthopaedic Advances 28(3):215-223, 2019).

The CH 2 Cl 2 /MeOH (1:1) extract of the aerial parts of Tephrosia subtriflora afforded a new flavanonol, named subtriflavanonol (1), along with the known flavanone spinoflavanone B, and the known flavanonols MS-II (2) and mundulinol. The structures were elucidated by the use of NMR spectroscopy and mass spectrometry. The absolute configuration of the flavanonols was determined based on quantum chemical ECD calculations. In the antiplasmodial assay, compound 2 showed the highest activity against chloroquine-sensitive Plasmodium falciparum reference clones (D6 and 3D7), artemisinin-sensitive isolate (F32-TEM) as well as field isolate (KSM 009) with IC 50 values 1.4-4.6 μM without significant cytotoxicity against Vero and HEp2 cell lines (IC 50  > 100 μM). The new compound (1) showed weak antiplasmodial activity, IC 50 12.5-24.2 μM, but also showed selective anticancer activity against HEp2 cell line (CC 50 16.9 μM).

Introduction: Stiffness and loss of motion following total knee arthroplasty (TKA) is a complex and multifactorial complication that may require manipulation under anesthesia (MUA). However, patient and surgical factors that potentially influence the development of knee stiffness following TKA are not fully understood. The purpose of this study was to identify patient and surgical factors that may influence range of motion loss following TKA by assessing a cohort of patients that underwent MUA and comparing them to a matched cohort of patients without complications., Materials and Methods: The joints registry was searched for patients who underwent MUA following primary TKA between 2004 and 2013. Demographic and surgical information was obtained from the electronic medical record including range of motion (ROM), comorbidities and timing of MUA. Patients who underwent MUA were then double-matched by baseline (prior to primary TKA) knee ROM to patients who underwent primary TKA with normal postoperative range of motion recovery during the same time period., Results: Fifty-two patients (fifty-six knees) (66% female, mean BMI 32.4 kg/m2) underwent MUA after TKA during the study period. MUA was performed a mean of 13.6 weeks after primary TKA. Study patients were double-matched by baseline flexion (mean 107º±2º) to 111 patients (112 knees) with a similar mean baseline flexion (104º±2º, p=0.138). Patients requiring MUA were younger (mean age 56 vs. 64 years, p<0.001), had more comorbidities (5 vs. 3, p<0.001), and a higher number of previous knee surgeries (56% vs. 21%, p<0.001) compared with controls. The risk for requiring MUA following primary TKA was significantly higher (2.4, p<0.001) in patients with previous knee surgery (arthroscopy for meniscal pathology, ACL reconstruction, osteotomies). Tourniquet time, length of stay, number of physical therapy sessions, blood loss >50 mL, and any complication during the hospital stay were not found to be associated with an increased risk of requiring MUA., Conclusion: Younger patients with more comorbidities and a history of previous knee surgery were found to have significantly higher risk for developing stiffness and loss of motion requiring MUA after primary TKA in the current study. Patients with this risk profile need to be counseled regarding the risk for postoperative knee stiffness and range of motion loss possibly requiring MUA after primary TKA.

In its 15th year, the Global Emerging Infections Surveillance and Response System (GEIS) continued to make significant contributions to global public health and emerging infectious disease surveillance worldwide. As a division of the US Department of Defense's Armed Forces Health Surveillance Center since 2008, GEIS coordinated a network of surveillance and response activities through collaborations with 33 partners in 76 countries. The GEIS was involved in 73 outbreak responses in fiscal year 2011. Significant laboratory capacity-building initiatives were undertaken with 53 foreign health, agriculture and/or defense ministries, as well as with other US government entities and international institutions, including support for numerous national influenza centers. Equally important, a variety of epidemiologic training endeavors reached over 4,500 individuals in 96 countries. Collectively, these activities enhanced the ability of partner countries and the US military to make decisions about biological threats and design programs to protect global public health as well as global health security.

Capacity-building initiatives related to public health are defined as developing laboratory infrastructure, strengthening host-country disease surveillance initiatives, transferring technical expertise and training personnel. These initiatives represented a major piece of the Armed Forces Health Surveillance Center, Division of Global Emerging Infections Surveillance and Response System (AFHSC-GEIS) contributions to worldwide emerging infectious disease (EID) surveillance and response. Capacity-building initiatives were undertaken with over 80 local and regional Ministries of Health, Agriculture and Defense, as well as other government entities and institutions worldwide. The efforts supported at least 52 national influenza centers and other country-specific influenza, regional and U.S.-based EID reference laboratories (44 civilian, eight military) in 46 countries worldwide. Equally important, reference testing, laboratory infrastructure and equipment support was provided to over 500 field sites in 74 countries worldwide from October 2008 to September 2009. These activities allowed countries to better meet the milestones of implementation of the 2005 International Health Regulations and complemented many initiatives undertaken by other U.S. government agencies, such as the U.S. Department of Health and Human Services, the U.S. Agency for International Development and the U.S. Department of State.