Repression of Divergent Noncoding Transcription by a Sequence-Specific Transcription Factor.

Many active eukaryotic gene promoters exhibit divergent noncoding transcription, but the mechanisms restricting expression of these transcripts are not well understood. Here, we demonstrate how a sequence-specific transcription factor represses divergent noncoding transcription at highly expressed genes in yeast. We find that depletion of the transcription factor Rap1 induces noncoding transcription in a large fraction of Rap1-regulated gene promoters. Specifically, Rap1 prevents transcription initiation at cryptic promoters near its binding sites, which is uncoupled from transcription regulation in the protein-coding direction. We further provide evidence that Rap1 acts independently of previously described chromatin-based mechanisms to repress cryptic or divergent transcription. Finally, we show that divergent transcription in the absence of Rap1 is elicited by the RSC chromatin remodeler. We propose that a sequence-specific transcription factor limits access of basal transcription machinery to regulatory elements and adjacent sequences that act as divergent cryptic promoters, thereby providing directionality toward productive transcription.

In Vivo Photoadduction of Anesthetic Ligands in Mouse Brain Markedly Extends Sedation and Hypnosis.

Photoaffinity ligands are best known as tools used to identify the specific binding sites of drugs to their molecular targets. However, photoaffinity ligands have the potential to further define critical neuroanatomic targets of drug action. In the brains of WT male mice, we demonstrate the feasibility of using photoaffinity ligands in vivo to prolong anesthesia via targeted yet spatially restricted photoadduction of azi-m-propofol (aziPm), a photoreactive analog of the general anesthetic propofol. Systemic administration of aziPm with bilateral near-ultraviolet photoadduction in the rostral pons, at the border of the parabrachial nucleus and locus coeruleus, produced a 20-fold increase in the duration of sedative and hypnotic effects compared with control mice without UV illumination. Photoadduction that missed the parabrachial-coerulean complex also failed to extend the sedative or hypnotic actions of aziPm and was indistinguishable from nonadducted controls. Paralleling the prolonged behavioral and EEG consequences of on target in vivo photoadduction, we conducted electrophysiologic recordings in rostral pontine brain slices. Using neurons within the locus coeruleus to further highlight the cellular consequences of irreversible aziPm binding, we demonstrate transient slowing of spontaneous action potentials with a brief bath application of aziPm that becomes irreversible on photoadduction. Together, these findings suggest that photochemistry-based strategies are a viable new approach for probing CNS physiology and pathophysiology.SIGNIFICANCE STATEMENT Photoaffinity ligands are drugs capable of light-induced irreversible binding, which have unexploited potential to identify the neuroanatomic sites of drug action. We systemically administer a centrally acting anesthetic photoaffinity ligand in mice, conduct localized photoillumination within the brain to covalently adduct the drug at its in vivo sites of action, and successfully enrich irreversible drug binding within a restricted 250 µm radius. When photoadduction encompassed the pontine parabrachial-coerulean complex, anesthetic sedation and hypnosis was prolonged 20-fold, thus illustrating the power of in vivo photochemistry to help unravel neuronal mechanisms of drug action.

Factors Associated with and Impact of Open Conversion in Laparoscopic and Robotic Minor Liver Resections: An International Multicenter Study of 10,541 Patients.

INTRODUCTION: Despite the increasing widespread adoption and experience in minimally invasive liver resections (MILR), open conversion occurs not uncommonly even with minor resections and as been reported to be associated with inferior outcomes. We aimed to identify risk factors for and outcomes of open conversion in patients undergoing minor hepatectomies. We also studied the impact of approach (laparoscopic or robotic) on outcomes. METHODS: This is a post-hoc analysis of 20,019 patients who underwent RLR and LLR across 50 international centers between 2004-2020. Risk factors for and perioperative outcomes of open conversion were analysed. Multivariate and propensity score-matched analysis were performed to control for confounding factors. RESULTS: Finally, 10,541 patients undergoing either laparoscopic (LLR; 89.1%) or robotic (RLR; 10.9%) minor liver resections (wedge resections, segmentectomies) were included. Multivariate analysis identified LLR, earlier period of MILR, malignant pathology, cirrhosis, portal hypertension, previous abdominal surgery, larger tumor size, and posterosuperior location as significant independent predictors of open conversion. The most common reason for conversion was technical issues (44.7%), followed by bleeding (27.2%), and oncological reasons (22.3%). After propensity score matching (PSM) of baseline characteristics, patients requiring open conversion had poorer outcomes compared with successful MILR cases as evidenced by longer operative times, more blood loss, higher requirement for perioperative transfusion, longer duration of hospitalization and higher morbidity, reoperation, and 90-day mortality rates. CONCLUSIONS: Multiple risk factors were associated with conversion of MILR even for minor hepatectomies, and open conversion was associated with significantly poorer perioperative outcomes.

Impact of Liver Cirrhosis, Severity of Cirrhosis, and Portal Hypertension on the Difficulty and Outcomes of Laparoscopic and Robotic Major Liver Resections for Primary Liver Malignancies.

BACKGROUND: Minimally invasive liver resections (MILR) offer potential benefits such as reduced blood loss and morbidity compared with open liver resections. Several studies have suggested that the impact of cirrhosis differs according to the extent and complexity of resection. Our aim was to investigate the impact of cirrhosis on the difficulty and outcomes of MILR, focusing on major hepatectomies. METHODS: A total of 2534 patients undergoing minimally invasive major hepatectomies (MIMH) for primary malignancies across 58 centers worldwide were retrospectively reviewed. Propensity score (PSM) and coarsened exact matching (CEM) were used to compare patients with and without cirrhosis. RESULTS: A total of 1353 patients (53%) had no cirrhosis, 1065 (42%) had Child-Pugh A and 116 (4%) had Child-Pugh B cirrhosis. Matched comparison between non-cirrhotics vs Child-Pugh A cirrhosis demonstrated comparable blood loss. However, after PSM, postoperative morbidity and length of hospitalization was significantly greater in Child-Pugh A cirrhosis, but these were not statistically significant with CEM. Comparison between Child-Pugh A and Child-Pugh B cirrhosis demonstrated the latter had significantly higher transfusion rates and longer hospitalization after PSM, but not after CEM. Comparison of patients with cirrhosis of all grades with and without portal hypertension demonstrated no significant difference in all major perioperative outcomes after PSM and CEM. CONCLUSIONS: The presence and severity of cirrhosis affected the difficulty and impacted the outcomes of MIMH, resulting in higher blood transfusion rates, increased postoperative morbidity, and longer hospitalization in patients with more advanced cirrhosis. As such, future difficulty scoring systems for MIMH should incorporate liver cirrhosis and its severity as variables.

One node among many: sevoflurane-induced hypnosis and the challenge of an integrative network-level view of anaesthetic action.

Building on their known ability to influence sleep and arousal, Li and colleagues show that modulating the activity of glutamatergic pedunculopontine tegmental neurones also alters sevoflurane-induced hypnosis. This finding adds support for the shared sleep-anaesthesia circuit hypothesis. However, the expanding recognition of many neuronal clusters capable of modulating anaesthetic hypnosis raises the question of how disparate and anatomically distant sites ultimately interact to coordinate global changes in the state of the brain. Understanding how these individual sites work in concert to disrupt cognition and behaviour is the next challenge for anaesthetic mechanisms research.

Decoding the regulatory roles of non-coding RNAs in cellular metabolism and disease.

Non-coding RNAs, including long non-coding RNAs (lncRNAs), microRNAs (miRNAs), and circular RNAs (circRNAs), are being studied extensively in a variety of fields. Their roles in metabolism have received increasing attention in recent years but are not yet clear. The regulation of glucose, fatty acid, and amino acid metabolism is an imperative physiological process that occurs in living organisms and takes part in cancer and cardiovascular diseases. Here, we summarize the important roles played by non-coding RNAs in glucose metabolism, fatty acid metabolism, and amino acid metabolism, as well as the mechanisms involved. We also summarize the therapeutic advances for non-coding RNAs in diseases such as obesity, cardiovascular disease, and some metabolic diseases. Overall, non-coding RNAs are indispensable factors in metabolism and have a significant role in the three major metabolisms, which may be exploited as therapeutic targets in the future.

Clinical Insights into Structure, Regulation, and Targeting of ABL Kinases in Human Leukemia.

Chronic myeloid leukemia is a multistep, multi-lineage myeloproliferative disease that originates from a translocation event between chromosome 9 and chromosome 22 within the hematopoietic stem cell compartment. The resultant fusion protein BCR::ABL1 is a constitutively active tyrosine kinase that can phosphorylate multiple downstream signaling molecules to promote cellular survival and inhibit apoptosis. Currently, tyrosine kinase inhibitors (TKIs), which impair ABL1 kinase activity by preventing ATP entry, are widely used as a successful therapeutic in CML treatment. However, disease relapses and the emergence of resistant clones have become a critical issue for CML therapeutics. Two main reasons behind the persisting obstacles to treatment are the acquired mutations in the ABL1 kinase domain and the presence of quiescent CML leukemia stem cells (LSCs) in the bone marrow, both of which can confer resistance to TKI therapy. In this article, we systemically review the structural and molecular properties of the critical domains of BCR::ABL1 and how understanding the essential role of BCR::ABL1 kinase activity has provided a solid foundation for the successful development of molecularly targeted therapy in CML. Comparison of responses and resistance to multiple BCR::ABL1 TKIs in clinical studies and current combination treatment strategies are also extensively discussed in this article.

Risk Factors and Outcomes of Open Conversion During Minimally Invasive Major Hepatectomies: An International Multicenter Study on 3880 Procedures Comparing the Laparoscopic and Robotic Approaches.

INTRODUCTION: Despite the advances in minimally invasive (MI) liver surgery, most major hepatectomies (MHs) continue to be performed by open surgery. This study aimed to evaluate the risk factors and outcomes of open conversion during MI MH, including the impact of the type of approach (laparoscopic vs. robotic) on the occurrence and outcomes of conversions. METHODS: Data on 3880 MI conventional and technical (right anterior and posterior sectionectomies) MHs were retrospectively collected. Risk factors and perioperative outcomes of open conversion were analyzed. Multivariate analysis, propensity score matching, and inverse probability treatment weighting analysis were performed to control for confounding factors. RESULTS: Overall, 3211 laparoscopic MHs (LMHs) and 669 robotic MHs (RMHs) were included, of which 399 (10.28%) had an open conversion. Multivariate analyses demonstrated that male sex, laparoscopic approach, cirrhosis, previous abdominal surgery, concomitant other surgery, American Society of Anesthesiologists (ASA) score 3/4, larger tumor size, conventional MH, and Institut Mutualiste Montsouris classification III procedures were associated with an increased risk of conversion. After matching, patients requiring open conversion had poorer outcomes compared with non-converted cases, as evidenced by the increased operation time, blood transfusion rate, blood loss, hospital stay, postoperative morbidity/major morbidity and 30/90-day mortality. Although RMH showed a decreased risk of conversion compared with LMH, converted RMH showed increased blood loss, blood transfusion rate, postoperative major morbidity and 30/90-day mortality compared with converted LMH. CONCLUSIONS: Multiple risk factors are associated with conversion. Converted cases, especially those due to intraoperative bleeding, have unfavorable outcomes. Robotic assistance seemed to increase the feasibility of the MI approach, but converted robotic procedures showed inferior outcomes compared with converted laparoscopic procedures.

Severity of in vivo corticospinal tract degeneration is associated with survival in amyotrophic lateral sclerosis: a longitudinal, multicohort study.

BACKGROUND AND PURPOSE: This study sought to evaluate the relationship of progressive corticospinal tract (CST) degeneration with survival in patients with amyotrophic lateral sclerosis (ALS). METHODS: Forty-one ALS patients and 42 healthy controls were prospectively recruited from the Canadian ALS Neuroimaging Consortium. Magnetic resonance imaging scanning and clinical evaluations were performed on participants at three serial visits with 4-month intervals. Texture analysis was performed on T1-weighted magnetic resonance imaging scans and the texture feature 'autocorrelation' was quantified. Whole-brain group-level comparisons were performed between patient subgroups. Linear mixed models were used to evaluate longitudinal progression. Region-of-interest and 3D voxel-wise Cox proportional-hazards regression models were constructed for survival prediction. For all survival analyses, a second independent cohort was used for model validation. RESULTS: Autocorrelation of the bilateral CST was increased at baseline and progressively increased over time at a faster rate in ALS short survivors. Cox proportional-hazards regression analyses revealed autocorrelation of the CST as a significant predictor of survival at 5 years follow-up (hazard ratio 1.28, p = 0.005). Similarly, voxel-wise whole-brain survival analyses revealed that increased autocorrelation of the CST was associated with shorter survival. ALS patients stratified by median autocorrelation in the CST had significantly different survival times using the Kaplan-Meier curve and log-rank tests (χ2  = 7.402, p = 0.007). CONCLUSIONS: Severity of cerebral degeneration is associated with survival in ALS. CST degeneration progresses faster in subgroups of patients with shorter survival. Neuroimaging holds promise as a tool to improve patient management and facilitation of clinical trials.

Early vs late drain removal after pancreatic resection-a systematic review and meta-analysis.

BACKGROUND: Reducing clinically relevant post-operative pancreatic fistula (CR-POPF) incidence after pancreatic resections has been a topic of great academic interest. Optimizing post-operative drain management is a potential strategy in reducing this major complication. METHODS: Studies involving pancreatic resections, including both pancreaticoduodenectomy (PD) and distal pancreatic resections (DP), with intra-operative drain placement were screened. Early drain removal was defined as removal before or on the 3rd post-operative day (POD) while late drain removal was defined as after the 3rd POD. The primary outcome was CR-POPF, International Study Group of Pancreatic Surgery (ISGPS) Grade B and above. Secondary outcomes were all complications, severe complications, post-operative haemorrhage, intra-abdominal infections, delayed gastric emptying, reoperation, length of stay, readmission, and mortality. RESULTS: Nine studies met the inclusion criteria and were included for analysis. The studies had a total of 8574 patients, comprising 1946 in the early removal group and 6628 in the late removal group. Early drain removal was associated with a significantly lower risk of CR-POPF (OR: 0.24, p < 0.01). Significant reduction in risk of post-operative haemorrhage (OR: 0.55, p < 0.01), intra-abdominal infection (OR: 0.35, p < 0.01), re-admission (OR: 0.63, p < 0.01), re-operation (OR: 0.70, p = 0.03), presence of any complications (OR: 0.46, p < 0.01), and reduced length of stay (SMD: -0.75, p < 0.01) in the early removal group was also observed. CONCLUSION: Early drain removal is associated with significant reductions in incidence of CR-POPF and other post-operative complications. Further prospective randomised trials in this area are recommended to validate these findings.

The miR-185/PAK6 axis predicts therapy response and regulates survival of drug-resistant leukemic stem cells in CML.

Overcoming drug resistance and targeting cancer stem cells remain challenges for curative cancer treatment. To investigate the role of microRNAs (miRNAs) in regulating drug resistance and leukemic stem cell (LSC) fate, we performed global transcriptome profiling in treatment-naive chronic myeloid leukemia (CML) stem/progenitor cells and identified that miR-185 levels anticipate their response to ABL tyrosine kinase inhibitors (TKIs). miR-185 functions as a tumor suppressor: its restored expression impaired survival of drug-resistant cells, sensitized them to TKIs in vitro, and markedly eliminated long-term repopulating LSCs and infiltrating blast cells, conferring a survival advantage in preclinical xenotransplantation models. Integrative analysis with mRNA profiles uncovered PAK6 as a crucial target of miR-185, and pharmacological inhibition of PAK6 perturbed the RAS/MAPK pathway and mitochondrial activity, sensitizing therapy-resistant cells to TKIs. Thus, miR-185 presents as a potential predictive biomarker, and dual targeting of miR-185-mediated PAK6 activity and BCR-ABL1 may provide a valuable strategy for overcoming drug resistance in patients.

What gets resident physicians stressed and how would they prefer to be supported? A best-worst scaling study.

INTRODUCTION: Physician burnout has severe consequences on clinician well-being. Residents face numerous work-stressors that can contribute to burnout; however, given specialty variation in work-stress, it is difficult to identify systemic stressors and implement effective burnout interventions on an institutional level. Assessing resident preferences by specialty for common wellness interventions could also contribute to improved efficacy. METHODS: This cross-sectional study used best-worst scaling (BWS), a type of discrete choice modelling, to explore how 267 residents across nine specialties (anaesthesiology, emergency medicine, internal medicine, neurology, obstetrics and gynaecology, pathology, psychiatry, radiology and surgery) prioritised 16 work-stressors and 4 wellness interventions at a large academic medical centre during the COVID-19 pandemic (December 2020). RESULTS: Top-ranked stressors were work-life integration and electronic health record documentation. Therapy (63%, selected as 'would realistically consider intervention') and coaching (58%) were the most preferred wellness supports in comparison to group-based peer support (20%) and individual peer support (22%). Pathology, psychiatry and OBGYN specialties were most willing to consider all intervention options, with emergency medicine and internal medicine specialties least willing to consider intervention options. CONCLUSION: BWS can identify relative differences in surveyed stressors, allowing for the generation of specialty-specific stressor rankings and preferences for specific wellness interventions that can be used to drive institution-wide changes to improve clinician wellness. BWS surveys are a potential methodology for clinician wellness programmes to gather specific information on preferences to determine best practices for resident wellness.

Optimizing photoswitchable MEK.

Optogenetic approaches are transforming quantitative studies of cell-signaling systems. A recently developed photoswitchable mitogen-activated protein kinase kinase 1 (MEK1) enzyme (psMEK) short-circuits the highly conserved Extracellular Signal-Regulated Kinase (ERK)-signaling cascade at the most proximal step of effector kinase activation. However, since this optogenetic tool relies on phosphorylation-mimicking substitutions in the activation loop of MEK, its catalytic activity is predicted to be substantially lower than that of wild-type MEK that has been phosphorylated at these residues. Here, we present evidence that psMEK indeed has suboptimal functionality in vivo and propose a strategy to circumvent this limitation by harnessing gain-of-function, destabilizing mutations in MEK. Specifically, we demonstrate that combining phosphomimetic mutations with additional mutations in MEK, chosen for their activating potential, restores maximal kinase activity in vitro. We establish that this modification can be tuned by the choice of the destabilizing mutation and does not interfere with reversible activation of psMEK in vivo in both Drosophila and zebrafish. To illustrate the types of perturbations enabled by optimized psMEK, we use it to deliver pulses of ERK activation during zebrafish embryogenesis, revealing rheostat-like responses of an ERK-dependent morphogenetic event.

Detection of 14 High-Risk Human Papillomaviruses Using Digital LAMP Assays on a Self-Digitization Chip.

Cervical cancer is the fourth-leading cause of cancer deaths among women worldwide and most cases occur in developing countries. Detection of high-risk (HR) HPV, the etiologic agent of cervical cancer, is a primary screening method for cervical cancer. However, the current gold standard for HPV detection, real-time PCR, is expensive, time-consuming, and instrumentation-intensive. A rapid, low-cost HPV detection method is needed for cervical cancer screening in low-resource settings. We previously developed a digital loop-mediated isothermal amplification (dLAMP) assay for rapid, quantitative detection of nucleic acids without the need for thermocycling. This assay employs a microfluidic self-digitization chip to automatically digitize a sample into an array of nanoliter wells in a simple assay format. Here we evaluate the dLAMP assay and self-digitization chip for detection of the commonly tested 14 high-risk HPVs in clinical samples. The dLAMP platform provided reliable genotyping and quantitative detection of the 14 high-risk HPVs with high sensitivity, demonstrating its potential for simple, rapid, and low-cost diagnosis of HPV infection.

Resistance to state transitions in responsiveness is differentially modulated by different volatile anaesthetics in male mice.

BACKGROUND: Recent studies point to a fundamental distinction between population-based and individual-based anaesthetic pharmacology. At the population level, anaesthetic potency is defined as the relationship between drug concentration and the likelihood of response to a stimulus. At the individual level, even when the anaesthetic concentration is held constant, fluctuations between the responsive and unresponsive states are observed. Notably, these spontaneous fluctuations exhibit resistance to state transitions Rst. Therefore, the response probability in each individual depends not just upon the drug concentration, but also upon responses to previous stimuli. Here, we hypothesise that Rst is distinct from drug potency and is differentially modulated by different anaesthetics. METHODS: Adult (14-24 weeks old) C57BL/6J male mice (n=60) were subjected to repeated righting reflex (RR) assays at equipotent steady-state concentrations of isoflurane (0.6 vol%), sevoflurane (1.0 vol%), and halothane (0.4 vol%). RESULTS: Fluctuations in RR were observed for all tested anaesthetics. Analysis of these fluctuations revealed that Rst was differentially modulated by different anaesthetics (F[2, 56.01]=49.59; P<0.0001). Fluctuations in RR were modelled using a stochastic dynamical system. This analysis confirmed that the amount of noise that drives behavioural state transitions depends on the anaesthetic agent (F[2, 42.86]=16.72; P<0.0001). CONCLUSIONS: Whilst equipotent doses of distinct anaesthetics produce comparable population response probabilities, they engage dramatically different dynamics in each individual animal. This manifests as a differential aggregate propensity to exhibit state transitions. Thus, resistance to state transitions is a fundamentally distinct, novel measure of individualised anaesthetic pharmacology.

A Guide to Understanding "State-of-the-Art" Basic Research Techniques in Anesthesiology.

Perioperative medicine is changing from a "protocol-based" approach to a progressively personalized care model. New molecular techniques and comprehensive perioperative medical records allow for detection of patient-specific phenotypes that may better explain, or even predict, a patient's response to perioperative stress and anesthetic care. Basic science technology has significantly evolved in recent years with the advent of powerful approaches that have translational relevance. It is incumbent on us as a primarily clinical specialty to have an in-depth understanding of rapidly evolving underlying basic science techniques to incorporate such approaches into our own research, critically interpret the literature, and improve future anesthesia patient care. This review focuses on 3 important and most likely practice-changing basic science techniques: next-generation sequencing (NGS), clustered regularly interspaced short palindromic repeat (CRISPR) modulations, and inducible pluripotent stem cells (iPSCs). Each technique will be described, potential advantages and limitations discussed, open questions and challenges addressed, and future developments outlined. We hope to provide insight for practicing physicians when confronted with basic science articles and encourage investigators to apply "state-of-the-art" technology to their future experiments.

Frequency and Outcomes of Elevated Perioperative Lactate Levels in Adult Congenital Heart Disease Patients Undergoing Cardiac Surgery.

OBJECTIVES: To assess whether lactate levels are associated with clinical outcomes in adult congenital heart disease patients who undergo cardiac surgery. DESIGN: Retrospective study. SETTING: Single quaternary academic referral center. PARTICIPANTS: Adult congenital heart disease patients (≥18 y old) with congenital heart disease undergoing cardiac surgery with cardiopulmonary bypass. INTERVENTIONS: Participants were classified into 3 groups according to their peak arterial lactate level within the first 48 hours of surgery. MEASUREMENTS AND MAIN RESULTS: In-hospital 30-day mortality, hospital and intensive care unit length of stay, duration of mechanical ventilation after surgery, acute kidney injury defined by Acute Kidney Injury Network criteria, and intensive care unit and hospital readmission within 30 days of surgery were examined. There was no significant difference among different lactate level groups in acute kidney injury, hospital length of stay, intensive care unit length of stay, hours of mechanical ventilation, need for redo surgery, or rates of hospital or intensive care unit readmission. In multivariable analysis, which included cardiopulmonary bypass time, redo surgery, nonelective case, and the adult congenital heart disease complexity score, lactate levels were not a significant predictor of either acute kidney injury or hospital length of stay. CONCLUSIONS: The appeal of using lactate levels to risk stratify-patients or to develop a model to predict mortality and morbidity has potential merit, but currently there is insufficient evidence to use lactate levels as a predictor of outcomes in adult patients with congenital heart disease undergoing cardiac surgery.

A mechanistic investigation of thrombotic microangiopathy associated with IV abuse of Opana ER.

Since 2012, a number of case reports have described the occurrence of thrombotic microangiopathy (TMA) following IV abuse of extended-release oxymorphone hydrochloride (Opana ER), an oral opioid for long-term treatment of chronic pain. Here, we present unique clinical features of 3 patients and investigate IV exposure to the tablet's inert ingredients as a possible causal mechanism. Guinea pigs were used as an animal model to understand the hematopathologic and nephrotoxic potential of the inert ingredient mixture (termed here as PEO+) which primarily contains high-molecular-weight polyethylene oxide (HMW PEO). Microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney injury were found in a group of 3 patients following recent injection of adulterated extended-release oxymorphone tablets. Varying degrees of cardiac involvement and retinal ischemia occurred, with TMA evident on kidney biopsy. A TMA-like state also developed in guinea pigs IV administered PEO+. Acute tubular and glomerular renal injury was accompanied by nonheme iron deposition and hypoxia-inducible factor-1α upregulation in the renal cortex. Similar outcomes were observed following dosing with HMW PEO alone. IV exposure to the inert ingredients in reformulated extended-release oxymorphone can elicit TMA. Although prescription opioid abuse shows geographic variation, all physicians should be highly inquisitive of IV drug abuse when presented with cases of TMA.

23.4% Hypertonic Saline and Intracranial Pressure in Severe Traumatic Brain Injury Among Children: A 10-Year Retrospective Analysis.

OBJECTIVE: To explore the effect of 23.4% hypertonic saline for management of elevated intracranial pressure in children admitted to our institution for severe traumatic brain injury. DESIGN: Single-center, retrospective medical chart analysis. SETTING: A PICU at a level 1 pediatric trauma center in the United States. PATIENTS: Children admitted for severe traumatic brain injury from 2006 to 2016 who received 23.4% hypertonic saline and whose intracranial pressures were measured within 5 hours of receiving 23.4% hypertonic saline. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Over the 10-year period, 1,587 children were admitted for traumatic brain injury, 155 of whom were deemed severe per this study's criteria. Forty of these children received at least one dose of hypertonic saline, but 14 were excluded for insufficient intracranial pressure data. Among the remaining 26 children, one hundred one 23.4% hypertonic saline boluses were used in the analysis. Use of 23.4% hypertonic saline was associated with a decrease in intracranial pressure of approximately 7 mm Hg at both within 1 hour after the bolus (p < 0.01) and 4 hours after the bolus (p < 0.01) when compared with the intracranial pressure measured within 1 hour before the hypertonic saline bolus. These effects remained significant after adjusting for Functional Status Scale score and CT Marshall scores. There was no statistically significant association between adjunctive therapies, such as antiepileptics and analgesics, and changes in intracranial pressure. There was no laboratory evidence of hyperkalemia or renal injury after use of 23.4% hypertonic saline. Across all hospitalizations, 65% of the study population demonstrated an abnormally elevated creatinine at least once, but only three episodes of acute kidney injury occurred in total, all before hypertonic saline administration. Eight of the 26 children in this analysis died during their hospitalization. The Functional Status Scale scores ranged from 6 to 26 with a mean of 12.2 and SD of 5.7. CONCLUSIONS: Use of 23.4% hypertonic saline with children admitted for severe traumatic brain injury is associated with a statistically significant decrease in intracranial pressure within 1 hour of use.

Identification and characterization of RNA aptamers: A long aptamer blocks the AMPA receptor and a short aptamer blocks both AMPA and kainate receptors.

AMPA and kainate receptors, along with NMDA receptors, represent different subtypes of glutamate ion channels. AMPA and kainate receptors share a high degree of sequence and structural similarities, and excessive activity of these receptors has been implicated in neurological diseases such as epilepsy. Therefore, blocking detrimental activity of both receptor types could be therapeutically beneficial. Here, we report the use of an in vitro evolution approach involving systematic evolution of ligands by exponential enrichment with a single AMPA receptor target (i.e. GluA1/2R) to isolate RNA aptamers that can potentially inhibit both AMPA and kainate receptors. A full-length or 101-nucleotide (nt) aptamer selectively inhibited GluA1/2R with a KI of ∼5 µm, along with GluA1 and GluA2 AMPA receptor subunits. Of note, its shorter version (55 nt) inhibited both AMPA and kainate receptors. In particular, this shorter aptamer blocked equally potently the activity of both the GluK1 and GluK2 kainate receptors. Using homologous binding and whole-cell recording assays, we found that an RNA aptamer most likely binds to the receptor's regulatory site and inhibits it noncompetitively. Our results suggest the potential of using a single receptor target to develop RNA aptamers with dual activity for effectively blocking both AMPA and kainate receptors.