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Background: The coronavirus disease 2019 (COVID-19) pandemic caused major transitions in total joint arthroplasty (TJA), notably with the increased utilization of same-day discharge (SDD) pathways. This study assessed the effect of accelerated discharge pathways following the resumption of elective cases during the COVID-19 pandemic on SDD rates, adverse events, and characteristics associated with successful SDD following total hip and total knee arthroplasty. Methods: This retrospective study split patients into cohorts: TJA prior to COVID-19 (pre-COVID, July 2019-December 2019) and TJA following the resumption of elective surgeries (post-COVID, July 2020-December 2020). Patient characteristics such as age, sex, body mass index, American Society of Anesthesiologists score, and pertinent comorbidities were analyzed, and length of stay, 30-day emergency department (ED) visit rates, readmissions, and reoperations were compared. Results: A total of 1333 patients met inclusion criteria that were divided into pre-COVID (692) and post-COVID (641) cohorts. The pre-COVID group had a median age of 69 years (interquartile range 63-76), and the post-COVID group had a median age of 68 years (interquartile range 61-75) (P = .024). SDD increased from 0.1% to 28.9% (P < .001), and length of stay decreased from 1.3 days to 0.89 days (P < .001). There was no change in 30-day ED visits, readmissions, or reoperations (P = .817, P = .470, and P = .643, respectively). There was no difference in ED visits, readmissions, or reoperations in SDD patients. The odds of SDD were associated with age (P < .001, odds ratio [OR] = 0.94), body mass index (P = .006, OR = 0.95), male sex (P < .001, OR = 1.83), and history of tobacco use (P < .001, OR = 1.87). Conclusions: At our institution, the COVID-19 pandemic accelerated the utilization of SDD pathways without increasing ED visits, readmissions, or reoperations.

Background:. The goal of this study was to assess whether adding a latissimus dorsi (LD) flap to a secondary implant-based reconstruction (IBR) improves outcomes following explantation of the primary device due to infection. Methods:. We conducted a retrospective study of patients who underwent a second IBR with or without the addition of an LD flap during 2006–2019, following explantation due to infection. Surgical outcomes were collected and compared between reconstruction types. Results:. A total of 6093 IBRs were identified during the study period. Of these, 109 underwent a second attempt at breast reconstruction with IBR alone (n = 86, 79%) or IBR/LD (n = 23, 21%) following explantation of an infected device. Rates of secondary device explantation due to a complication were similar between the two groups (26% in the IBR/LD group and 21% in the IBR group; P = 0.60). Among the patients who underwent prior radiotherapy, the IBR/LD group had lower rates of any complication (38% versus 56%; P = 0.43), infection (25% versus 44%; P = 0.39), and reconstruction failure (25% versus 44%; P = 0.39); however, differences were not statistically significant. Conclusion:. Following a failed primary breast reconstruction due to infection, it may be appropriate to offer a secondary reconstruction. For patients with a history of radiotherapy, combining an LD flap with IBR may provide benefits over IBR alone. Although not statistically different, this outcome may have clinical significance, considering the magnitude of the effect, and may result in decreased complication rates and a higher chance of reconstructive success.

Summary:. Cross facial nerve grafts (CFNGs) are one of the most ubiquitous and time-honored surgical tools used in facial reanimation. They may be used for targeting different mimetic muscles in the subacute setting as well as to innervate newly placed muscle flaps in varied facial subunits. In our experience, when used specifically for smile reanimation in two-stage strategies with either traditional “babysitting” approaches in nerve transfers or free functional muscle transfers, the second stage may present some challenges in CFNG identification as well as injury to the previously banked nerve graft. We present some technical modifications in the first-stage CFNG inset that can make the second stage easier and safer. These modifications include: (1) marking the course of the nerve graft with surgical metal clips and inserting loose circumferential sutures throughout the distal course of the nerve in the recipient area to avoid displacement; (2) transferring the nerve graft through the nasal sills rather than lips, protecting it from damage during insertion of free functional muscle transfer; and (3) routing the nerve from the lateral nose to the preauricular area over the zygomatic arch, allowing easier dissection and banking of adequate graft length to provide tension-free coaptation with the flexibility of nerve coaptation in variable positions.

Background: Studies have demonstrated magnetic resonance imaging (MRI) safety in the presence of MRI-conditional permanent pacemakers (PPM). However, since patients’ care may require serial MRIs, it is necessary to evaluate device safety and performance after multiple scans. Objectives: We evaluated safety and performance of MRI-conditional PPMs after serial MRIs over various anatomic regions performed during a multicenter, prospective, single-arm study (ProMRI). Methods: ProMRI was a multiphase observational study designed to evaluate PPM performance after MRI scans. Our study evaluated PPM function in a cohort of patients who underwent multiple 1.5-T MRI scans. Selected patients underwent separate head, chest, and lumbar spine MRIs. Pacing capture threshold (PCT), lead impedance (LI), sensing amplitude, and battery capacity were collected before and after scanning. Freedom from serious adverse device effects (SADE) through 1 month post MRI served as a primary endpoint. Changes in PPM function parameters, including threshold success rate and sensing attenuation, were analyzed for statistical significance and clinical relevance. Results: In 81 patients no adverse events or SADE occurred. Statistically significant changes in ventricular PCT (0.034 ± 0.15 V) immediately after, ventricular LI immediately after (-18.7 ± 44.2 Ω) and 1 month post phase B (-19.8 ± 44.9 Ω), and atrial sensing attenuation immediately after (-0.27 ± 0.92 mV) and 1 month post phase B (-0.22 ± 0.92 mV) were noted. However, these changes were not clinically relevant in degree. Conclusion: These results demonstrate the safety and performance of the ProMRI PPM in patients undergoing 3 serial MRIs over various anatomic regions.

Purpose: Selective internal radiation therapy (SIRT) is administered to treat tumors of the liver and is generally well tolerated. Although widely adopted for its therapeutic benefits, SIRT is rarely combined with external beam radiation therapy (EBRT) owing to the complexity of the dosimetry resulting from the combination of treatments with distinct radiobiological effects. The purpose of this study was to establish a dosimetric framework for combining SIRT and EBRT using clinical experience derived from representative patients with hepatocellular carcinoma (HCC) who received both therapies. Methods and Materials: Treatments from 10 patients with HCC given EBRT either before or after SIRT were analyzed. The dosimetry framework used here considered differences in the radiobiological effects and fractionation schemes of SIRT versus EBRT, making use of the concepts of biological effective dose (BED) and equivalent dose (EQD). Absorbed dose from SIRT was calculated, converted to BED, and summed with BED from EBRT dose plans. Two of these patients were used in a virtual planning exercise to investigate the feasibility of combining stereotactic body radiation therapy and SIRT. Results: The combination of EBRT and SIRT in 10 patients with HCC showed no major toxicity. No Child-Pugh scores went above 8 and albumin-bilirubin scores from only 1 patient worsened to grade 3 (> -1.39) from treatment through 3-months follow-up. A framework with radiobiological modeling was developed to manage the combined treatments in terms of their sum BED. The exploratory SIRT plus SABR inverse dose plans for 2 patients, incorporating radiobiologically informed 90Y SIRT dosimetry, achieved dose distributions comparable to SBRT alone. Conclusions: Treatment with both EBRT and SIRT can be given safely to patients with HCC. The BED and EQD concepts should be used in combined dosimetry to account for the differing radiobiological effects of EBRT and SIRT. Inverse dose planning of EBRT after SIRT could provide improved dose distributions and flexibility to the clinical workflow. Further research into combination therapy is needed through prospective trials.

Intravenous therapy is a common practice among many specialties. Intravenous therapy extravasation is a potential complication to such therapy. Hospitals without a dedicated wound care team trained in these interventions will often default to plastic surgical consultation, making an understanding of available interventions essential to the initial evaluation and management of these injuries. The goal of this article was to provide plastic surgeons and health care providers with a general overview of the acute management of intravenous infiltration and extravasation injuries. Though the decision for surgical versus nonsurgical management is often a clear one for plastic surgeons, local interventions, and therapies are often indicated and under-utilized in the immediate postinfiltration period. Thorough knowledge of these interventions should be a basic requirement in the armamentarium of plastic surgery consultants.

Abstract: The synovial folds of the cervical spine are regarded as a potential source of neck pain and headache, especially following whiplash injury. Damage to the synovial folds following motor vehicle trauma has been well documented in post-mortem studies. However, methods of identifying injury to the synovial folds in the survivors of motor vehicle trauma have proven elusive to date. Recently, it has been made possible to image the synovial folds in vivo using magnetic resonance imaging. This now makes it feasible to investigate the potential involvement of synovial folds in the generation of neck pain and headache and its relief using spinal manipulation. This paper reviews critically the morphology of the synovial folds of the cervical spine that underpins the hypotheses proposed to explain their functional and clinical significance and a new system of naming and classifying the synovial folds is presented. Although there is some evidence to support the contribution of the synovial folds to neck pain, several theories have little or no support and require investigation and further evaluation. These findings have implications for understanding the anatomical basis of neck pain and headache and the rationale for the use of spinal manipulation in their management. [ABSTRACT FROM AUTHOR]

Purpose: Long COVID brain fog is often disabling. Yet, no empirically-supported treatments exist. This study's objectives were to evaluate feasibility and efficacy, provisionally, of a new rehabilitation approach, Constraint-Induced Cognitive Therapy (CICT), for post-COVID-19 cognitive sequelae., Design: Sixteen community-residents ≥ 3-months post-COVID-19 infection with mild cognitive impairment and dysfunction in instrumental activities of daily living (IADL) were enrolled. Participants were randomized to Immediate-CICT or treatment-as-usual (TAU) with crossover to CICT. CICT combined behavior change techniques modified from Constraint-Induced Movement Therapy with Speed of Processing Training, a computerized cognitive-training program. CICT was deemed feasible if (a) ≥80% of participants completed treatment, (b) the same found treatment highly satisfying and at most moderately difficult, and (c) <2 study-related, serious adverse-events occurred. The primary outcome was IADL performance in daily life (Canadian Occupational Performance Measure). Employment status and brain fog (Mental Clutter Scale) were also assessed., Results: Fourteen completed Immediate-CICT ( n =7) or TAU ( n =7); two withdrew from TAU before their second testing session. Completers were [ M (S D )]: 10 (7) months post-COVID; 51 (13) years old; 10 females, 4 males; 1 African American, 13 European American. All the feasibility benchmarks were met. Immediate-CICT, relative to TAU, produced very large improvements in IADL performance ( M =3.7 points, p<.001, d =2.6) and brain fog ( M =-4 points, p<.001, d =-2.9). Four of five non-retired Immediate-CICT participants returned-to-work post-treatment; no TAU participants did, p =.048., Conclusions: CICT has promise for reducing brain fog, improving IADL, and promoting returning-to-work in adults with Long COVID. Findings warrant a large-scale RCT with an active-comparison group.

Background: Cancer is associated with increased venous thromboembolism in children. Risk factors for venous thromboembolism in this cohort include using central venous catheters, mass effect from underlying malignancy, chemotherapy, and surgery. Anticoagulation management in this cohort is challenging, given recurrent episodes of thrombocytopenia, the need for invasive procedures, and coagulopathy. A quality improvement (QI) initiative was developed to improve hematology consultation services and provide documentation of an individualized anticoagulation care plan for this high-risk cohort., Methods: Through the use of QI methods, interviews of stakeholders, expert consensus, and review of baseline data, a multidisciplinary team was organized, and key drivers relevant to improving access to hematology consultations and documentation of individualized anticoagulation care plans were identified. We used a Plan-Do-Study-Act model to improve hematology consultations and documentation of anticoagulation care plan (process measure). Outcome measures were bleeding and thrombosis recurrence/progression., Results: Seventeen patients with oncologic and venous thromboembolism diagnoses were included as baseline data. Slightly over half of these patients [53% (n = 9)] had a hematology consultation, and 7 (43.8%) had documentation of an anticoagulation care plan. After implementing QI methods, all 34 patients (100%) received hematology consultations and documentation of an anticoagulation care plan, and this measure was sustained for 1 year. Bleeding and thrombosis rates were similar in the baseline and post-QI cohorts., Conclusions: QI interventions proved effective in sustaining access to hematology consultations and providing anticoagulation care plans for patients with concomitant improved anticoagulation plan documentation for patients., Competing Interests: The authors have no financial interest to declare in relation to the content of this article., (Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.)

Our goal was to survey people with epilepsy (PWE) about their interest in and factors that may influence willingness and ability to participate in an exercise randomized controlled trial (RCT). A brief survey was administered to 100 PWE asking if they would take part in a hypothetical 6-week exercise intervention RCT. Follow-up questions queried reasons for and against participation and why participation would be difficult. Sixty-nine percent of respondents indicated willingness to participate. The top reason for participation was "to improve overall health with exercise" (n = 49). The top reason for why participation would be difficult was they "do not have a reliable source of transportation" (n = 27). The top reason for not participating was "not interested in research participation" (n = 19). Preliminary results were used to budget for transportation in a prospective RCT (NCT04959019). Of the first 27 PWE enrolled (63 % female; 44 % African American/Black), six (50 % female; 50 % African American/Black) have used the transportation service. The majority of PWE surveyed were interested in participating in an exercise RCT, but some indicated barriers. Accommodating transportation in an ongoing RCT has facilitated recruitment of PWE who would otherwise not be able to participate. Barriers to participation should be accounted for when designing studies., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: JPS is the Editor-in-Chief of Epilepsy & Behavior Reports, associate editor of Journal of Epileptology, editorial board member for Epilepsy & Behavior, Journal of Medical Science, and Folia Medica Copernicana, and receives royalties from Elsevier; receives funding from NIH, NSF, DoD, Shor Foundation for Epilepsy Research, UCB Biosciences, NeuroPace Inc., SAGE Therapeutics Inc., Serina Therapeutics Inc., LivaNova Inc., Greenwich Biosciences Inc., Biogen Inc., Eisai Inc., State of AL; is on consulting /advisory boards for PureTech Health, Biopharmaceutical Research Company, LivaNova Inc., UCB Pharma, AdCel Pharma, iFovea Inc.; has served on the Alabama State Medical Cannabis Study Commission (nominated by Gov. Ivey); serves on the Alabama Medical Cannabis Commission (2021–2025; nominated by Dr. Scott Harris, State Health Officer). JBA is associate editor of Epilepsy & Behavior Reports; receives funding from NIH, McKnight Brain Institute, DoD, LivaNova Inc.; has served as a consultant for LivaNova, Inc.; has received honoraria from Cleveland Clinic and University of Auckland and travel funds from the International League Against Epilepsy; serves on a Data Safety Monitoring Board (University of Alabama at Birmingham/University of Colorado Anschutz Medical Campus); serves on the American Epilepsy Society Scientific Program Committee. The rest of the authors have no disclosures to declare., (© 2023 The Authors. Published by Elsevier Inc.)

This study provides insights into the electronic structure of an atomically precise Fe/Co 6 Se 8 cluster and the extent of redox cooperativity between the Fe active site and the noninnocent Co 6 Se 8 support. Chemical oxidation studies enable the isolation of two types of oxidized Fe/Co 6 Se 8 clusters, in which the nature of the counterion (I - or OTf - ) significantly impacts the structural interactions between Fe and the Co 6 Se 8 unit. Experimental characterization by single crystal X-ray diffraction, 57 Fe Mössbauer spectroscopy, and 31 P{ 1 H} NMR spectroscopy is complemented by computational analysis. In aggregate, the study reveals that upon oxidation, the charge is shared between the Fe edge site and the Co 6 Se 8 core.

Here, we investigate the stereoelectronic requirements of a family of Fe/Co 6 Se 8 molecular clusters to achieve a Goldilocks regime of substrate affinity for the catalytic coupling of tosyl azide and tert -butyl isocyanide. The reactivity of a catalytically competent iron-nitrenoid intermediate, observed in situ , is explored toward nitrene transfer and hydrogen-atom abstraction. The dual role of isocyanide, which, on the one hand, prevents catalyst degradation but, in large amounts, slows down reactivity, is exposed. The impact of distal changes (the number of neighboring active sites and the identity of supporting ligands) on the substrate affinity, electronic properties, and catalytic activity is investigated. Overall, the study reveals that the dynamic, push-pull interactions between the substrate ( t BuNC), active site (Fe), and support (Co 6 Se 8 ) create a regime where increased substrate activation occurs with facile dissociation.

This study provides atomistic insights into the interface between a single-site catalyst and a transition metal chalcogenide support and reveals that peak catalytic activity occurs when edge/support redox cooperativity is maximized. A molecular platform MCo 6 Se 8 (PEt 3 ) 4 (L) 2 ( 1 -M, M = Cr, Mn, Fe, Co, Cu, and Zn) was designed in which the active site (M)/support (Co 6 Se 8 ) interactions are interrogated by systematically probing the electronic and structural changes that occur as the identity of the metal varies. All 3d transition metal 1 -M clusters display remarkable catalytic activity for coupling tosyl azide and tert -butyl isocyanide, with Mn and Co derivatives showing the fastest turnover in the series. Structural, electronic, and magnetic characterization of the clusters was performed using single crystal X-ray diffraction, 1 H and 31 P nuclear magnetic resonance spectroscopy, electronic absorption spectroscopy, cyclic voltammetry, and computational methods. Distinct metal/support redox regimes can be accessed in 1 -M based on the energy of the edge metal's frontier orbitals with respect to those of the cluster support. As the degree of electronic interaction between the edge and the support increases, a cooperative regime is reached wherein the support can deliver electrons to the catalytic site, increasing the reactivity of key metal-nitrenoid intermediates.

This study uncovers the interconnected reactivity of the three catalytically active sites of an atomically precise nanocluster Cr 3 (py) 3 Co 6 Se 8 L 6 ( 1 (py) 3 , L = Ph 2 PNTol - , Ph = phenyl, Tol = 4-tolyl). Catalytic and stoichiometric studies into tosyl azide activation and carbodiimide formation enabled the isolation and crystallographic characterization of key catalytically competent metal-imido intermediates, including the tris(imido) cluster 1 (NTs) 3 , the catalytic resting state 1 (NTs) 3 (CN t Bu) 3 , and the site-differentiated mono(imido) cluster 1 (NTs)(CN t Bu) 2 . In the stoichiometric regime, nitrene transfer proceeds via a stepwise mechanism, with the three active sites engaging sequentially to produce carbodiimide. Moreover, the chemical state of neighboring active sites was found to regulate the affinity for substrates of an individual Cr-imido edge site, as revealed by comparative structural analysis and CN t Bu binding studies.

We demonstrate that allosteric effects and redox state changes can be harnessed to create a switch that selectively and reversibly regulates the coordination chemistry of a single site on the surface of a molecular cluster. This redox-switchable allostery is employed as a guiding force to assemble the molecular clusters Zn 3 Co 6 Se 8 L' 6 (L' = Ph 2 PN(H)Tol, Ph = phenyl, Tol = 4-tolyl) into materials of predetermined dimensionality (1- or 2-D) and to encode them with emissive properties. This work paves the path to program the assembly and function of inorganic clusters into stimuli-responsive, atomically precise materials., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

A new strategy is reported to tailor the electronic properties of a superatomic metal chalcogenide cluster by redox matching the cluster core with surface tin(IV) sites. Two ternary clusters (SnR 2 ) 3 Co 6 Se 8 L 6 (R = Me, n Bu) are synthesized by salt metathesis from the hexalithiated salt [Li 2 (py) 2 ] 3 Co 6 Se 8 L 6 and R 2 SnCl 2 . Cyclic and differential-pulse voltammetry studies reveal that the tristannylated clusters feature two new, near-degenerate, electronic states within the highest occupied molecular orbital-lowest unoccupied molecular orbital gap of the Co 6 Se 8 core, which are attributed to the reduction of a surface tin site. Single-crystal X-ray diffraction analysis reveals that no Sn···Se coordination is present in the solid state. The single-crystal X-ray structure of the hexalithiated salt starting material is reported for the tetrahydrofuran (THF) adduct variant [Li 2 (THF) 2 ] 6 Co 6 Se 8 L 6 .

Atomically defined interfaces that maximize the density of active sites and harness the electronic metal-support interaction are desirable to facilitate challenging multielectron transformations, but their synthesis remains a considerable challenge. We report the rational synthesis of the atomically defined metal chalcogenide nanopropeller Fe 3 Co 6 Se 8 L 6 (L = Ph 2 PNTol) featuring three Fe edge sites, and its ensuing catalytic activity for carbodiimide formation. The complex interaction between the Fe edges and Co 6 Se 8 support, including the interplay between oxidation state, substrate coordination, and metal-support interaction, is probed in detail using chemical and electrochemical methods, extensive single crystal X-ray diffraction, and electronic absorption and Mössbauer spectroscopy.

Alkylation of d- or l-phenylalanine or valine alkyl esters was carried out using methyl or phenyl Grignard reagents. Subsequent condensation with salicylaldehyde, 3,5-di-tert-butylsalicylaldehyde, or 5-fluorosalicylaldehyde formed tridentate, X2L type, Schiff base ligands. Chiral shift NMR confirmed retention of stereochemistry during synthesis. X-ray crystal structures of four of the ligands show either inter- or intramolecular hydrogen bonding interactions. The ligands coordinate to the titanium reagents Ti(NMe2)4 or TiCl(NMe2)3 by protonolysis and displacement of two equivalents of HNMe2. The crystal structure of one example of Ti(X2L)Cl(NMe2) was determined and the complex has a distorted square pyramidal geometry with an axial NMe2 ligand. The bis-dimethylamide complexes are active catalysts for the ring closing hydroamination of di- and trisubstituted aminoallenes. The reaction of hepta-4,5-dienylamine at 135 °C with 5 mol% catalyst gives a mixture of 6-ethyl-2,3,4,5-tetrahydropyridine (40-72%) and both Z- and E-2-propenyl-pyrrolidine (25-52%). The ring closing reaction of 6-methyl-hepta-4,5-dienylamine at 135 °C with 5 mol% catalyst gives exclusively 2-(2-methyl-propenyl)-pyrrolidine. The pyrrolidine products are obtained with enantiomeric excesses up to 17%.

We have recently reported that activation of Brd4 is associated with the presence of autophagy in NPMc+ and MLL AML cells. In order to determine the mechanisms underlying this relationship, we have examined the role of Brd4 in regulating the expression of several genes that are central to the process of autophagy. We found that Brd4 binds to the promoters of ATG 3, 7 and CEBPβ, and expression of these genes is markedly reduced by inhibitors of Brd4, as well as by Brd4-shRNA and depletion of CEBPβ. Inhibitors of Brd4 also dramatically suppress the transcription of Keap1, thereby increasing the expression of anti-oxidant genes through the Nrf2 pathway and reducing the cytotoxicity induced by Brd4 inhibitors. Elimination of ATG3 or KEAP1 expression using CRISPR-cas9 mediated genomic editing markedly reduced autophagy. We conclude that Brd4 plays a significant role in autophagy activation through the direct transcriptional regulation of genes essential for it, as well as through the Keap1-Nrf2 axis in NPMc+ and MLL-fusion AML cells., Competing Interests: CONFLICTS OF INTEREST The authors declare no conflicts of interest.

Check-in/Check-out (CICO) is an intervention designed to improve behavioral outcomes for students identified as at-risk for school failure. Core principles of the intervention include clearly defined behavioral expectations and rules, precorrections for meeting behavioral expectations, high rates of feedback and reinforcement for demonstration of desired behavior, use of data to monitor outcomes, and a system for school-to- home communication. The purpose of this investigation was to use the 2014 Council for Exceptional Children's quality indicators and standards for establishing evidence-based practices in special education to review the existing research for CICO. Implications regarding the use of different sets of quality indicators to evaluate extant research are provided, and recommendations for future research are discussed.

The mechanisms underlying activation of the BET pathway in AML cells remain poorly understood. We have discovered that autophagy is activated in acute leukemia cells expressing mutant nucleophosmin 1 (NPMc+) or MLL-fusion proteins. Autophagy activation results in the degradation of NPM1 and HEXIM1, two negative regulators of BET pathway activation. Inhibition of autophagy with pharmacologic inhibitors or through knocking down autophagy-related gene 5 (Atg5) expression increases the expression of both NPM1 and HEXIM1. The Brd4 inhibitors JQ1 and I-BET-151 also inhibit autophagy and increase NPM1 and HEXIM1 expression. We conclude that the degradation of NPM1 and HEXIM1 through autophagy in certain AML subsets contributes to the activation of the BET pathway in these cells.

Purpose: The ErbB3-binding protein 1 (Ebp1) has been implicated in diverse cancers as having either oncogenic or tumor suppressor activities. The present study was undertaken to determine the effects of Ebp1 expression in AML cells and to determine the mechanisms by which Ebp1 promotes cell proliferation in these cells., Experimental Design: The expression of Ebp1 was studied in mononuclear cells obtained from the peripheral blood of 54 patients with AML by Western blot analysis. The effects of Ebp1 expression on proliferating cell nuclear antigen (PCNA) expression and cell proliferation was measured using Western blot analysis, immunoprecipitation, in vitro ubiquitination, and colony-forming assays. The role of Ebp1 in promoting rRNA synthesis and cell proliferation was evaluated by measuring the level of pre-rRNA and the recruitment of Pol I to rDNA., Results: Ebp1 is highly expressed in acute myelogenous leukemia (AML) cells and regulates the level of ribosomal RNA (rRNA) synthesis by binding to RNA Polymerase I (Pol I) and enhancing the formation of the Pol I initiation complex. Ebp1 also increases the stability of PCNA protein by preventing its interaction with Mdm2, for which it is a substrate., Conclusions: These results demonstrate an important role of Ebp1 in promoting cell proliferation in AML cells through the regulation of both rRNA synthesis and PCNA expression. Clin Cancer Res; 22(13); 3320-7. ©2016 AACR., (©2016 American Association for Cancer Research.)

Purpose: This study was performed to determine whether the investigational proteasome inhibitor ixazomib demonstrated selective antineoplastic activity against acute myelogenous leukemia cells expressing a mutated nucleophosmin-1 gene and to gain a better understanding of its mechanisms of action., Experimental Design: The cytotoxic effects of ixazomib treatment were analyzed in human acute myelogenous leukemia (AML) cell lines and primary AML samples expressing wild-type or mutated NPM1 (NPMc(+)). The potential roles of oxidative stress in mediating cytotoxic activity were determined using flow cytometry, enzyme-based assays, and Western blots., Results: Apoptosis induced by ixazomib was abrogated by knockdown of NPM1/NPMc(+)expression using an inducible shRNA construct and enhanced by NPMc(+)overexpression. Cytotoxicity was associated with superoxide generation and was reduced by the addition of the antioxidant N-acetylcysteine. AML cells expressing NPMc(+)had significantly reduced levels of intracellular glutathione and NADPH associated with reduced antioxidant responses to drug treatment. Treatment of 3 patients with relapsed NPMc(+)AML resulted in an antileukemic effect in 1 patient as demonstrated by a marked reduction of leukemic blasts in the peripheral blood. Efficacy was associated with superoxide generation, reduced glutathione levels, and reduced mRNA and protein expression of antioxidant effectors in responding cells., Conclusions: In this study, a direct association was observed between NPMc(+)expression in AML, reduced antioxidant responses, and enhanced sensitivity to an oral proteasome inhibitor that induces oxidative stress. These data suggest that intracellular determinants of antioxidant responses may be good predictors of therapeutic response to ixazomib., (©2015 American Association for Cancer Research.)

Problem: There is a recognized need to translate scientific discoveries to patient-oriented clinical research (POCR). Several obstacles interfere with the successful recruitment and retention of physicians for POCR careers., Approach: The American Society of Hematology developed a yearlong educational and mentoring experience, the Clinical Research Training Institute (CRTI), for early-career physician-scientists from multiple institutions throughout the United States and Canada pursuing POCR careers. Several academic outcome measures of the 140 participants in the first seven years (2003-2010) of CRTI were evaluated by reviewing former trainee participants' curriculum vitae and survey responses., Outcomes: Ethnic, racial, and gender diversity of CRTI trainees was reflective of the proportions represented across U.S. hematology/oncology fellowship programs. Eighty-six percent (109/126) of trainees reported success establishing a POCR study; nearly half (62/126) had primarily research-focused jobs. Former CRTI trainees received at least 262 external grant awards and published 1,035 peer-reviewed manuscripts, 173 chapters, and 115 review articles., Next Steps: Because mentorship is key to developing a successful career, the CRTI program is being modified to enhance longitudinal mentorship by CRTI faculty mentors and mentors at trainees' home institutions, as well as to encourage the establishment of collaborations and the potential for research project success. Efforts to make the CRTI experience available to more phy sicians, include more CRTI graduates as faculty, and increase participation by hematologists from backgrounds under represented in medicine are under way.

Telomere shortening is common in bone marrow failure syndromes such as dyskeratosis congenita (DC), aplastic anemia (AA) and myelodysplastic syndromes (MDS). However, improved knowledge of the lineage-specific consequences of telomere erosion and restoration of telomere length in hematopoietic progenitors is required to advance therapeutic approaches. We have employed a reversible murine model of telomerase deficiency to compare the dependence of erythroid and myeloid lineage differentiation on telomerase activity. Fifth generation Tert-/- (G5 Tert-/-) mice with shortened telomeres have significant anemia, decreased erythroblasts and reduced hematopoietic stem cell (HSC) populations associated with neutrophilia and increased myelopoiesis. Intracellular multiparameter analysis by mass cytometry showed significantly reduced cell proliferation and increased sensitivity to activation of DNA damage checkpoints in erythroid progenitors and in erythroid-biased CD150hi HSC, but not in myeloid progenitors. Strikingly, Cre-inducible reactivation of telomerase activity restored hematopoietic stem and progenitor cell (HSPC) proliferation, normalized the DNA damage response, and improved red cell production and hemoglobin levels. These data establish a direct link between the loss of TERT activity, telomere shortening and defective erythropoiesis and suggest that novel strategies to restore telomerase function may have an important role in the treatment of the resulting anemia.

The ability of a cell to undergo malignant transformation is both associated with and dependent on a concomitant increase in protein synthesis due to increased cell division rates and biosynthetic activities. Protein synthesis, in turn, depends upon the synthesis of ribosomes and thus ultimately on the transcription of ribosomal RNA by RNA polymerase I that occurs in the nucleolus. Enlargement of nucleoli has long been considered a hallmark of the malignant cell, but it is only recently that the rate of synthesis of rRNA in the nucleolus has been recognized as both a critical regulator of cellular proliferation and a potential target for therapeutic intervention. As might be expected, the factors regulating rRNA synthesis are both numerous and complex. It is the objective of this review to highlight recent advances in understanding how rRNA synthesis is perturbed in transformed mammalian cells and to consider the impact of these findings on the development of new approaches to the treatment of malignancies. In-depth analysis of the process of rRNA transcription itself may be found in several recently published reviews (Drygin et al., 2010, Annu Rev Pharmacol Toxicol 50:131-156; Bywater et al., 2013,Cancer Cell 22: 51-65; Hein et al., 2013,Trends Mol Med 19:643-654)., (© 2014 Wiley Periodicals, Inc.)

Mycophenolic acid (MPA) is the active metabolite of mycophenolate mofetil, an effective immunosuppressive drug. Both MPA and mycophenolate mofetil are highly specific inhibitors of guanine nucleotide synthesis and of T-cell activation. However, the mechanism by which guanine nucleotide depletion suppresses T-cell activation is unknown. Depletion of GTP inhibits ribosomal RNA synthesis in T cells by inhibiting transcription initiation factor I (TIF-IA), a GTP-binding protein that recruits RNA polymerase I to the ribosomal DNA promoter. TIF-IA-GTP binds the ErbB3-binding protein 1, and together they enhance the transcription of proliferating cell nuclear antigen (PCNA). GTP binding by TIF-IA and ErbB3-binding protein 1 phosphorylation by protein kinase C δ are both required for optimal PCNA expression. The protein kinase C inhibitor sotrastaurin markedly potentiates the inhibition of ribosomal RNA synthesis, PCNA expression, and T-cell activation induced by MPA, suggesting that the combination of the two agents are more highly effective than either alone in inducing immunosuppression., (© 2015 by The American Society of Hematology.)

Objectives: Survival disparities in acute myeloid leukemia (AML) among blacks and Hispanics have been described but not studied extensively in adults. Although younger age and cytogenetic profiles of t(8;21) and acute promyelocytic leukemia (APL) subtypes of AML are associated with improved survival, these factors have not been investigated by race. The purpose is to evaluate whether the observed survival differences for blacks and Hispanics with AML are attributable to older age at diagnosis or lower rates of favorable cytogenetic profiles at diagnosis. The hypothesis is that survival disparities for blacks and Hispanics with AML will be explained by older age at diagnosis and lower rates of favorable cytogenetics., Methods: Patients with AML were identified in the Surveillance Epidemiology and End Results database (1999 to 2008). Kaplan-Meier (KM) survival curves predicted survival by race/ethnicity, stratified by age. Cox proportional hazard models estimated mortality by race with adjustment for age, sex, year of diagnosis, t(8;21), and APL subtypes., Results: A total of 25,692 patients were included. Blacks and Hispanics were diagnosed at younger ages (younger than 61 y), and had higher rates of t(8;21) and APL compared with non-Hispanic whites (NHWs). The overall KM curve shows that NHWs had a worse survival compared with other races/ethnicities. However, when KM curves were stratified by age, blacks and Hispanics had worse survival in younger age categories (younger than 61 y). In multivariable models, black race was associated with an increased risk of death compared with NHWs (HR, 1.10; 95% CI, 1.04-1.16). Adjustment for t(8;21) and APL subtypes did not attenuate the disparity., Conclusions: Despite younger age and higher prevalence of favorable cytogenetics at diagnosis, blacks and Hispanics have an increased mortality from AML compared with other racial/ethnic groups. Future studies should investigate other factors that may influence outcomes among minority populations.

A new sonochemical process for the top-down production of silicon nanoparticles (<1 nm) with surface functional groups is described. The procedure involves a combination of acoustic cavitation erosion of a single-crystalline silicon surface coupled with simultaneous reaction with a reactive organic compound such as 1-hexyne. The sonochemical formation of the photoluminescent silicon nanoparticles by reactive cavitation erosion can be easily up-scaled.

We describe a novel two-step method, starting from bulk silicon wafers, to construct DNA conjugated silicon nanoparticles (SiNPs). This method first utilizes reactive high-energy ball milling (RHEBM) to obtain alkene grafted SiNPs. The alkene moieties are subsequently reacted with commercially available thiol-functionalized DNA via thiol-ene click chemistry to produce SiNP DNA conjugates wherein the DNA is attached through a covalent thioether bond. Further, to show the utility of this synthetic strategy, we illustrate how these SiNP ODN conjugates can detect cancer-associated miR-21 via a fluorescence ON strategy. Given that an array of biological molecules can be prepared with thiol termini and that SiNPs are biocompatible and biodegradable, we envision that this synthetic protocol will find utility in salient SiNP systems for potential therapeutic and diagnostic applications.

Accurate understanding of analyte boiling points (BP) is of critical importance in gas chromatographic (GC) separation and crude oil refinery operation in petrochemical industries. This study reported the first combined use of GC separation and partial-least-square (PLS1) multivariate regression analysis of petrochemical structural activity relationship (SAR) for accurate BP determination of two commercially available (D3710 and MA VHP) calibration gas mix samples. The results of the BP determination using PLS1 multivariate regression were further compared with the results of traditional simulated distillation method of BP determination. The developed PLS1 regression was able to correctly predict analytes BP in D3710 and MA VHP calibration gas mix samples, with a root-mean-square-%-relative-error (RMS%RE) of 6.4%, and 10.8% respectively. In contrast, the overall RMS%RE of 32.9% and 40.4%, respectively obtained for BP determination in D3710 and MA VHP using a traditional simulated distillation method were approximately four times larger than the corresponding RMS%RE of BP prediction using MRA, demonstrating the better predictive ability of MRA. The reported method is rapid, robust, and promising, and can be potentially used routinely for fast analysis, pattern recognition, and analyte BP determination in petrochemical industries., (Copyright © 2014 Elsevier B.V. All rights reserved.)

The transcription initiation factor I (TIF-IA) is an important regulator of the synthesis of ribosomal RNA (rRNA) through its facilitation of the recruitment of RNA polymerase I (Pol I) to the ribosomal DNA promoter. Activation of the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) pathway, which occurs commonly in acute myelogenous leukemia, enhances rRNA synthesis through TIF-IA stabilization and phosphorylation. We have discovered that TIF-IA coexists with a splicing isoform, TIF-90, which is expressed preferentially in the nucleolus and at higher levels in proliferating and transformed hematopoietic cells. TIF-90 interacts directly with Pol I to increase rRNA synthesis as a consequence of Akt activation. Furthermore, TIF-90 binds preferentially to a 90-kDa cleavage product of the actin binding protein filamin A (FLNA) that inhibits rRNA synthesis. Increased expression of TIF-90 overcomes the inhibitory effect of this cleavage product and stimulates rRNA synthesis. Because activated Akt also reduces FLNA cleavage, these results indicate that activated Akt and TIF-90 function in parallel to increase rRNA synthesis and, as a consequence, cell proliferation in leukemic cells. These results provide evidence that the direct targeting of Akt would be an effective therapy in acute leukemias in which Akt is activated., (© 2014 by The American Society of Hematology.)

Transcription initiation factor I (TIF-IA) plays an essential role in regulating ribosomal RNA (rRNA) synthesis by tethering RNA polymerase I (Pol I) to the rDNA promoter. We have found that activated Akt enhances rRNA synthesis through the phosphorylation of casein kinase IIα (CK2α) on a threonine residue near its N terminus. CK2 in turn phosphorylates TIF-IA, thereby increasing rDNA transcription. Activated Akt also stabilizes TIF-IA, induces its translocation to the nucleolus, and enhances its interaction with Pol I. Treatment with AZD8055, an inhibitor of both Akt and mammalian target of rapamycin phosphorylation, but not with rapamycin, disrupts Akt-mediated TIF-IA stability, translocation, and activity. These data support a model in which activated Akt enhances rRNA synthesis both by preventing TIF-IA degradation and phosphorylating CK2α, which in turn phosphorylates TIF-IA. This model provides an explanation for the ability of activated Akt to promote cell proliferation and, potentially, transformation.

Mutations in exon 12 of the nucleophosmin (NPM1) gene (NPMc+ (NPM1 COOH terminal mutations)) define a distinct subset of acute myelogenous leukemias (AMLs), in which the NPMc+ protein localizes aberrantly to the leukemic cell cytoplasm. We have found that introduction of the most common NPMc+ variant into K562 and 32D cells sensitizes these cells to apoptosis induced by drugs such as bortezomib and arsenic trioxide (ATO) that induce reactive oxygen species (ROS) formation, and that cytotoxicity is prevented in the presence of N-acetyl-L-cysteine (NAC), an ROS scavenger. The substitution of tryptophan 288 (W288) by cysteine occurs in the great majority of NPM1c+ mutations. Mutagenesis of cysteine 288 to alanine re-localizes NPMc+ from the cytoplasm to the nucleolus and attenuates the sensitivity of cells expressing this mutation to bortezomib and ATO. Primary AML cells expressing NPMc+ are also significantly more sensitive than other AML cells to apoptosis induced by both drugs at pharmacologically achievable doses. We conclude that the presence of a cysteine moiety at position 288 results in the cytoplasmic localization of NPM1c+ and the increased sensitivity to bortezomib and ATO. These data suggest that bortezomib and ATO may have increased therapeutic efficacy in NPM1c+ leukemias.

Although it is frequently hypothesized that surface (like surface charge) and physical characteristics (like particle size) play important roles in cellular interactions of nanoparticles (NPs), a systematic study probing this issue is missing. Hence, a comparative cytotoxicity study, quantifying nine different cellular endpoints, was performed with a broad series of monodisperse, well characterized silicon (Si) and germanium (Ge) NPs with various surface functionalizations. Human colonic adenocarcinoma Caco-2 and rat alveolar macrophage NR8383 cells were used to clarify the toxicity of this series of NPs. The surface coatings on the NPs appeared to dominate the cytotoxicity: the cationic NPs exhibited cytotoxicity, whereas the carboxylic acid-terminated and hydrophilic PEG- or dextran-terminated NPs did not. Within the cationic Si NPs, smaller Si NPs were more toxic than bigger ones. Manganese-doped (1% Mn) Si NPs did not show any added toxicity, which favors their further development for bioimaging. Iron-doped (1% Fe) Si NPs showed some added toxicity, which may be due to the leaching of Fe(3+) ions from the core. A silica coating seemed to impart toxicity, in line with the reported toxicity of silica. Intracellular mitochondria seem to be the target for the toxic NPs since a dose-, surface charge- and size-dependent imbalance of the mitochondrial membrane potential was observed. Such an imbalance led to a series of other cellular events for cationic NPs, like decreased mitochondrial membrane potential (ΔΨm) and ATP production, induction of ROS generation, increased cytoplasmic Ca(2+) content, production of TNF-α and enhanced caspase-3 activity. Taken together, the results explain the toxicity of Si NPs/Ge NPs largely by their surface characteristics, provide insight into the mode of action underlying the observed cytotoxicity, and give directions on synthesizing biocompatible Si and Ge NPs, as this is crucial for bioimaging and other applications in for example the field of medicine.