A single post-exposure oxime RS194B treatment rapidly reactivates acetylcholinesterase and reverses acute symptoms in macaques exposed to diethylphosphorothioate parathion and chlorpyrifos insecticides.

Millions of individuals globally suffer from inadvertent, occupational or self-harm exposures from organophosphate (OP) insecticides, significantly impacting human health. Similar to nerve agents, insecticides are neurotoxins that target and inhibit acetylcholinesterase (AChE) in central and peripheral synapses in the cholinergic nervous system. Post-exposure therapeutic countermeasures generally include administration of atropine with an oxime to reactivate the OP-inhibited AChE. However, animal model studies and recent clinical trials using insecticide-poisoned individuals have shown minimal clinical benefits of the currently approved oximes and their efficacy as antidotes has been debated. Currently used oximes either reactivate poorly, do not readily cross the blood-brain barrier (BBB), or are rapidly cleared from the circulation and must be repeatedly administered. Zwitterionic oximes of unbranched and simplified structure, for example RS194B, have been developed that efficiently cross the BBB resulting in reactivation of OP-inhibited AChE and dramatic reversal of severe clinical symptoms in mice and macaques exposed to OP insecticides or nerve agents. Thus, a single IM injection of RS194B has been shown to rapidly restore blood AChE and butyrylcholinesterase (BChE) activity, reverse cholinergic symptoms, and prevent death in macaques following lethal inhaled sarin and paraoxon exposure. The present macaque studies extend these findings and assess the ability of post-exposure RS194B treatment to counteract oral poisoning by highly toxic diethylphosphorothioate insecticides such as parathion and chlorpyrifos. These OPs require conversion by P450 in the liver of the inactive thions to the active toxic oxon forms, and once again demonstrated RS194B efficacy to reactivate and alleviate clinical symptoms within 60 mins of a single IM administration. Furthermore, when delivered orally, the Tmax of RS194B at 1-2 h was in the same range as those administered IM but were maintained in the circulation for longer periods greatly facilitating the use of RS194B as a non-invasive treatment, especially in isolated rural settings.

Dexamethasone and Surgical-Site Infection.

BACKGROUND: The glucocorticoid dexamethasone prevents nausea and vomiting after surgery, but there is concern that it may increase the risk of surgical-site infection. METHODS: In this pragmatic, international, noninferiority trial, we randomly assigned 8880 adult patients who were undergoing nonurgent, noncardiac surgery of at least 2 hours' duration, with a skin incision length longer than 5 cm and a postoperative overnight hospital stay, to receive 8 mg of intravenous dexamethasone or matching placebo while under anesthesia. Randomization was stratified according to diabetes status and trial center. The primary outcome was surgical-site infection within 30 days after surgery. The prespecified noninferiority margin was 2.0 percentage points. RESULTS: A total of 8725 participants were included in the modified intention-to-treat population (4372 in the dexamethasone group and 4353 in the placebo group), of whom 13.2% (576 in the dexamethasone group and 572 in the placebo group) had diabetes mellitus. Of the 8678 patients included in the primary analysis, surgical-site infection occurred in 8.1% (354 of 4350 patients) assigned to dexamethasone and in 9.1% (394 of 4328) assigned to placebo (risk difference adjusted for diabetes status, -0.9 percentage points; 95.6% confidence interval [CI], -2.1 to 0.3; P<0.001 for noninferiority). The results for superficial, deep, and organ-space surgical-site infections and in patients with diabetes were similar to those of the primary analysis. Postoperative nausea and vomiting in the first 24 hours after surgery occurred in 42.2% of patients in the dexamethasone group and in 53.9% in the placebo group (risk ratio, 0.78; 95% CI, 0.75 to 0.82). Hyperglycemic events in patients without diabetes occurred in 22 of 3787 (0.6%) in the dexamethasone group and in 6 of 3776 (0.2%) in the placebo group. CONCLUSIONS: Dexamethasone was noninferior to placebo with respect to the incidence of surgical-site infection within 30 days after nonurgent, noncardiac surgery. (Funded by the Australian National Health and Medical Research Council and others; PADDI Australian New Zealand Clinical Trials Registry number, ACTRN12614001226695.).

Long-Term Echocardiographic and Clinical Outcomes After Invasive and Non-Invasive Therapies for Sub-Massive and Massive Acute Pulmonary Embolism.

AIM: Acute pulmonary embolism (PE) is a significant cause of mortality in the hospital setting. The objective of this study was to outline the long-term outcomes after surgical and non-surgical management for patients with massive and submassive PE. METHODS: Population cohort observational study evaluating all patients who presented to three tertiary hospitals in the state of Western Australia with access to cardiothoracic services over 5 years (2013-2018). Reviewed notes of all patients as well as radiology, linked mortality data and all available echocardiography studies at the primary hospital. RESULTS: In total, 245 patients were identified, of which 41 received surgical management and 204 non-surgical management; demographic data was similar. Clinically, the surgical group had higher rates of shock requiring vasopressors, severe bradycardia, or cardiopulmonary resuscitation prior to intervention. The 28-day mortality was not statistically significantly different between the surgical embolectomy group (2/41 [4.2%]) and the non-surgical group (17/201 [8.3%]) (p=0.382). There was no difference in 12-month mortality, including when this was adjusted for vasopressors, right ventricular (RV) strain, troponin, and brain natriuretic peptide. In the massive PE sub-group, 28-day mortality was not significantly different: 2/29 (6.9%) surgical group vs 7/34 (20.2%) non-surgical group (p=0.064). Higher rates of severe RV impairment and dilatation were present in the surgical group. All patients with available echocardiography studies at outpatient follow-up returned to normal or mild RV impairment. CONCLUSION: Patients who presented with massive or submassive PE had similar outcomes whether treated with surgical or non-surgical management. Surgical embolectomy is a safe option in a cardiothoracic centre setting.

Acoustic Shadowing to Facilitate Ultrasound Guided Arterial Cannulation: A Systematic Review and Meta-analysis of Randomized Controlled Trials.

Aim and background: Ultrasound-guided arterial catheterization is a frequently performed procedure. Additional techniques such as acoustic shadowing-assisted ultrasound may be useful in improving success rate. This systematic review aimed to assess the efficacy of acoustic shadowing assisted ultrasound for arterial catheterization. Materials and methods: PubMed, Medline, EMBASE, Cochrane Library, EMCARE, and MedNar were searched in January 2024. Randomized controlled trials comparing the first attempt success rate of arterial catheterization using acoustic shadowing ultrasound vs unassisted ultrasound were included. Data were pooled for risk ratios (RRs) using the random-effects model. Subgroup analysis was conducted based on a single or double acoustic line. Sensitivity analysis was undertaken after excluding pediatric data. The certainty of evidence (COE) was assessed using the GRADE framework. Results: Six randomized controlled trials (n = 777) were included. A meta-analysis found the first attempt success rate is significantly higher in the acoustic ultrasound group (n = 6, RR: 0.47, 95% CI: 0.34-0.66, p ≤ 0.00001). Hematoma formation was significantly less in the acoustic ultrasound group (n = 6, RR: 0.52, 95% CI: 0.34-0.80, p = 0.003). First attempt success was significantly higher in the single acoustic line ultrasound (USG) group compared to the unassisted ultrasound group (n = 3, RR: 0.41, 95% CI: 0.28-0.59, p ≤ 0.00001). Sensitivity analysis after excluding pediatric data was similar to the primary analysis (n = 5, RR: 0.50, 95% CI: 0.33-0.70, p ≤ 0.00001). Certainty of evidence was "Moderate" for the first attempt cannulation. Conclusions: Acoustic shadowing-assisted ultrasound improved first-attempt arterial catheterization success rate and was associated with reduced hematoma formation. How to cite this article: Mishra L, Rath C, Wibrow B, Anstey M, Ho K. Acoustic Shadowing to Facilitate Ultrasound Guided Arterial Cannulation: A Systematic Review and Meta-analysis of Randomized Controlled Trials. Indian J Crit Care Med 2024;28(7):677-685.

Dexamethasone and persistent wound pain: a prespecified analysis of the randomised Perioperative Administration of Dexamethasone and Infection (PADDI) trial.

BACKGROUND: Dexamethasone is commonly administered intraoperatively to prevent postoperative nausea and vomiting and is believed to have analgesic properties. It is unknown whether it has an impact on chronic wound pain. METHODS: In this prespecified embedded superiority substudy of the randomised PADDI trial, patients undergoing non-urgent noncardiac surgery received dexamethasone 8 mg or placebo intravenously after induction of anaesthesia, and were followed up for 6 months postoperatively. The primary outcome was the incidence of pain in the surgical wound at 6 months. Secondary outcomes included acute postoperative pain and correlates of chronic postsurgical pain. RESULTS: We included 8478 participants in the modified intention-to-treat population (4258 in the dexamethasone group and 4220 in the matched placebo group). The primary outcome occurred in 491 subjects (11.5%) in the dexamethasone arm and 404 (9.6%) subjects in the placebo arm (relative risk 1.2, 95% confidence interval 1.06-1.41, P=0.003). Maximum pain scores at rest and on movement in the first 3 postoperative days were lower in the dexamethasone group compared with the control group {median 5 (inter-quartile range [IQR] 3.0-8.0) vs 6 (IQR 3.0-8.0) and median 7 (IQR 5.0-9.0) vs 8 (IQR 6.0-9.0), P<0.001 for both}. Severity of postoperative pain was not predictive of chronic postsurgical pain. The severity of chronic postsurgical pain and the frequency of neuropathic features did not differ between treatment groups. CONCLUSION: Administration of dexamethasone 8 mg i.v. was associated with an increase in the risk of pain in the surgical wound 6 months after surgery. CLINICAL TRIAL REGISTRATION: ACTRN12614001226695.

Correct dosing of Prothrombinex-VF in normalising elevated international normalised ratio in critically ill patients: a prospective cohort pilot study.

BACKGROUND: Prothrombinex-VF is being increasingly used as an off-label therapy to correct non-warfarin-related elevations in international normalised ratio (INR) in the critically ill. Currently there are no dosing guidelines for such use. AIMS: To validate a prediction equation, embedded in a smartphone application (app), to guide dosing of Prothrombinex-VF in critically ill patients. METHODS: A prospective pilot cohort study of critically ill adult patients with elevated INRs who were treated with Prothrombinex-VF. The main outcome measured was INR following Prothrombinex-VF administration. RESULTS: Of the 31 patients included, five (16%) were taking warfarin prior to admission and 14 (45%) had chronic liver disease. There was a significant decrease in INR after Prothrombinex-VF treatment (P < 0.001) and a significant correlation between the app's predicted INRs and the measured INRs (r = 0.63 and P < 0.001). The app's predicted INRs were less accurate for patients with chronic liver disease than for those without. Overall, the app's recommendations achieved an INR either similar to (29.6%) or better than (55.6%) what would have been achieved had the warfarin reversal guidelines been applied to dose the Prothrombinex-VF. CONCLUSION: The app appeared to be reasonably accurate at predicting normalisation of elevated INRs after administration of Prothrombinex-VF, especially among patients without liver disease. Its dosing recommendations were similar to or possibly better than preexisting warfarin reversal guidelines in over 85% of the situations analysed, if we assume a higher dose of Prothrombinex-VF would achieve a greater reduction in INR than a lower dose.

The association between intraoperative cardiopulmonary bypass power and complications after cardiac surgery.

BACKGROUND: Low cardiac power (product of flow and pressure) has been shown to be associated with mortality in patients with cardiogenic shock after acute myocardial infarction, but has not been studied in cardiac surgical patients. This study's hypothesis was that cardiac power during cardiopulmonary bypass for cardiac surgery would have a greater association with adverse events than either flow or MAP (mean arterial pressure) alone. METHODS: We undertook a retrospective observational study using patient data from February 2015 to March 2022 undergoing cardiac surgery at Fiona Stanley Hospital in Perth Australia. Excluded were patient age less than 18 years old, patients undergoing thoracic transplantation, ventricular assist devices, off pump cardiac surgery and aortic surgery. The primary outcome was a composite outcome of 30-days mortality, stroke or new-onset renal insufficiency. RESULTS: Overall, 1984 cardiac surgeries were included in the analysis. Neither duration nor area below thresholds tested for power, MAP or flow was associated with the primary composite outcome. However, we found that an area below MAP thresholds 35-50 mmHg was associated with new renal insufficiency (adjusted odds ratio 1.17 [95% CI 1.02 to 1.35] for patients spending 10 min at 10 mmHg below 50 mmHg MAP compared to those who did not). CONCLUSIONS: This study suggests that MAP during cardiopulmonary bypass, but not power or flow, was an independent risk factor for adverse renal outcomes for cardiac surgical patients.

Covalent inhibition of hAChE by organophosphates causes homodimer dissociation through long-range allosteric effects.

Acetylcholinesterase (EC 3.1.1.7), a key acetylcholine-hydrolyzing enzyme in cholinergic neurotransmission, is present in a variety of states in situ, including monomers, C-terminally disulfide-linked homodimers, homotetramers, and up to three tetramers covalently attached to structural subunits. Could oligomerization that ensures high local concentrations of catalytic sites necessary for efficient neurotransmission be affected by environmental factors? Using small-angle X-ray scattering (SAXS) and cryo-EM, we demonstrate that homodimerization of recombinant monomeric human acetylcholinesterase (hAChE) in solution occurs through a C-terminal four-helix bundle at micromolar concentrations. We show that diethylphosphorylation of the active serine in the catalytic gorge or isopropylmethylphosphonylation by the RP enantiomer of sarin promotes a 10-fold increase in homodimer dissociation. We also demonstrate the dissociation of organophosphate (OP)-conjugated dimers is reversed by structurally diverse oximes 2PAM, HI6, or RS194B, as demonstrated by SAXS of diethylphosphoryl-hAChE. However, binding of oximes to the native ligand-free hAChE, binding of high-affinity reversible ligands, or formation of an SP-sarin-hAChE conjugate had no effect on homodimerization. Dissociation monitored by time-resolved SAXS occurs in milliseconds, consistent with rates of hAChE covalent inhibition. OP-induced dissociation was not observed in the SAXS profiles of the double-mutant Y337A/F338A, where the active center gorge volume is larger than in wildtype hAChE. These observations suggest a key role of the tightly packed acyl pocket in allosterically triggered OP-induced dimer dissociation, with the potential for local reduction of acetylcholine-hydrolytic power in situ. Computational models predict allosteric correlated motions extending from the acyl pocket toward the four-helix bundle dimerization interface 25 Å away.

A Multicenter Trial of Vena Cava Filters in Severely Injured Patients.

BACKGROUND: Whether early placement of an inferior vena cava filter reduces the risk of pulmonary embolism or death in severely injured patients who have a contraindication to prophylactic anticoagulation is not known. METHODS: In this multicenter, randomized, controlled trial, we assigned 240 severely injured patients (Injury Severity Score >15 [scores range from 0 to 75, with higher scores indicating more severe injury]) who had a contraindication to anticoagulant agents to have a vena cava filter placed within the first 72 hours after admission for the injury or to have no filter placed. The primary end point was a composite of symptomatic pulmonary embolism or death from any cause at 90 days after enrollment; a secondary end point was symptomatic pulmonary embolism between day 8 and day 90 in the subgroup of patients who survived at least 7 days and did not receive prophylactic anticoagulation within 7 days after injury. All patients underwent ultrasonography of the legs at 2 weeks; patients also underwent mandatory computed tomographic pulmonary angiography when prespecified criteria were met. RESULTS: The median age of the patients was 39 years, and the median Injury Severity Score was 27. Early placement of a vena cava filter did not result in a significantly lower incidence of symptomatic pulmonary embolism or death than no placement of a filter (13.9% in the vena cava filter group and 14.4% in the control group; hazard ratio, 0.99; 95% confidence interval [CI], 0.51 to 1.94; P = 0.98). Among the 46 patients in the vena cava filter group and the 34 patients in the control group who did not receive prophylactic anticoagulation within 7 days after injury, pulmonary embolism developed in none of those in the vena cava filter group and in 5 (14.7%) in the control group, including 1 patient who died (relative risk of pulmonary embolism, 0; 95% CI, 0.00 to 0.55). An entrapped thrombus was found in the filter in 6 patients. CONCLUSIONS: Early prophylactic placement of a vena cava filter after major trauma did not result in a lower incidence of symptomatic pulmonary embolism or death at 90 days than no placement of a filter. (Funded by the Medical Research Foundation of Royal Perth Hospital and others; Australian New Zealand Clinical Trials Registry number, ACTRN12614000963628.).

Dexamethasone and clinically significant postoperative nausea and vomiting: a prespecified substudy of the randomised perioperative administration of dexamethasone and infection (PADDI) trial.

BACKGROUND: Clinically significant postoperative nausea and vomiting (PONV) is a patient-reported outcome which reflects patient experience. Although dexamethasone prevents PONV, it is unknown what impact it has on this experience. METHODS: In this prespecified embedded superiority substudy of the randomised Perioperative Administration of Dexamethasone and Infection (PADDI) trial, patients undergoing non-urgent noncardiac surgery received dexamethasone 8 mg or placebo intravenously after induction of anaesthesia, and completed a validated PONV questionnaire. The primary outcome was the incidence of clinically significant PONV on day 1 or day 2 postoperatively. Secondary outcomes included the incidence of clinically significant PONV and severe PONV on days 1 and 2 considered separately. RESULTS: A total of 1466 participants were included, with 733 patients allocated to the dexamethasone arm and 733 to matched placebo. The primary outcome occurred in 52 patients (7.1%) in the dexamethasone arm and 66 (9%) patients in the placebo arm (relative risk [RR]=0.79; 95% confidence interval [CI], 0.56-1.11; P=0.18). Severe PONV occurred on day 2 in 27 patients (3.9%) in the dexamethasone arm and 47 patients (6.7%) in the placebo arm (RR=0.58; 95% CI, 0.37-0.92; P=0.02; number needed-to-treat (NNT)=36.7; 95% CI, 20-202). In the entire cohort of 8880 PADDI patients, lower nausea scores, less frequent administration of antiemetics, and fewer vomiting events were recorded by patients in the dexamethasone arm up to day 2 after surgery. CONCLUSIONS: Administration of dexamethasone 8 mg i.v. did not influence clinically significant PONV. Dexamethasone administration did, however, decrease the incidence and severity of PONV, and was associated with less frequent administration of antiemetic agents. CLINICAL TRIAL REGISTRATION: ACTRN12614001226695.

Incremental cost of venous thromboembolism in trauma patients with contraindications to prophylactic anticoagulation: a prospective economic study.

Venous thromboembolism (VTE) is common in patients after major trauma. Attributable cost of VTE and whether this is related to the severity of injury have not been thoroughly investigated. We aimed to define the hospitalization costs of VTE and assess whether the costs were related to the severity of injury in this prospective economic study. Cost data of each patient enrolled in the da Vinci trial were drawn from hospital finance departments and standardized to 2020 Australian dollars (A$); and Injury Severity Score and Trauma Embolic Scoring System were used to quantify the severity of injury. Of the 223 patients who had complete financial cost data available until day-90 follow-up, 37 (16.6%) developed VTE, including upper limb (n = 3) and lower limb deep vein thrombosis (n = 25), pulmonary embolism (n = 7) and clots entrapped in a vena cava filter. The median total radiology (A$4307) as well as the hospitalization costs (A$138,526) of those who had VTE were significantly higher than those without VTE (A$1210; p < 0.001 and A$105,842; p = 0.023, respectively). The incremental hospitalization cost attributable to VTE was most apparent among those who had sustained extremely severe injuries, and estimated to be between A$43,292 (95% confidence interval [CI] 12,624-73,961, p = 0.006) and 41,680 (95%CI 7766-75,594, p = 0.016) after adjusted for Trauma Embolic Scoring System and Injury Severity Scores, respectively. VTE was common after major trauma and incurred a substantial incremental financial cost to the healthcare system, especially among those who had extremely severe injuries.

Early diagnosis of acute kidney injury subsequent to severe hypotension and fluid resuscitation in anaesthetized dogs.

OBJECTIVES: To document changes in urinary biomarker concentration and conventional diagnostic tests of acute kidney injury (AKI) following hypotension and fluid resuscitation in anaesthetized dogs. STUDY DESIGN: Experimental, repeated measures, prospective study. ANIMALS: A group of six male adult Greyhound dogs. METHODS: Following general anaesthesia, severe hypotension was induced by phlebotomy, maintaining mean arterial blood pressure (MAP) < 40 mmHg for 60 minutes, followed by resuscitation with intravenous gelatine solution to maintain MAP > 60 mmHg for 3 hours. Following euthanasia, renal tissue was examined by light microscopy (LM) and transmission electron microscopy (TEM). Urinary and serum concentrations of neutrophil gelatinase-associated lipocalin (NGAL), cystatin C (CysC), and gamma-glutamyl transpeptidase (GGT), serum creatinine and urine output were measured at baseline and hourly until euthanasia. Data are presented as mean and 95% confidence interval and analysed using repeated measures analysis of variance with Dunnett's adjustment, p < 0.05. RESULTS: Structural damage to proximal renal tubular cells was evident on LM and TEM. Urinary biomarker concentrations were significantly elevated from baseline, peaking 2 hours after haemorrhage at 19.8 (15.1-25.9) ng mL-1 NGAL (p = 0.002), 2.54 (1.64-3.43) mg mL-1 CysC (p = 0.009) and 2043 (790-5458) U L-1 GGT (p < 0.001). Serum creatinine remained within a breed-specific reference interval in all dogs. Urinary protein-creatinine ratio (UPC) was significantly elevated in all dogs from 1 hour following haemorrhage. CONCLUSIONS AND CLINICAL RELEVANCE: Urinary NGAL, CysC and GGT concentrations, and UPC were consistently elevated within 1 hour of severe hypotension, suggesting that proximal renal tubules are damaged in the earliest stage of ischaemia-reperfusion AKI. Measurement of urinary biomarkers may allow early diagnosis of AKI in anaesthetized dogs. Urinary GGT concentration and UPC are particularly useful as they can be measured on standard biochemistry analysers.

Management of Class III Malocclusion and Maxillary Transverse Deficiency with Microimplant-Assisted Rapid Palatal Expansion (MARPE): A Case Report.

Microimplant-assisted rapid palatal expansion (MARPE) has been demonstrated successfully in maxillary expansion in late adolescence and adulthood. The maxillary advancement accompanied by expansion is frequently anticipated, which is beneficial for the treatment of class III malocclusion. Airway volume increase can also be noted in some cases from the measurement of cone beam computerized tomography (CBCT) after expansion. The objective of this case report is to demonstrate the feasibility of applying MARPE on late adolescence patients with maxillary transverse deficiency and to present the changes in transverse and anteroposterior dimensions as well as the volume increase in velopharyngeal airway after MARPE. A 15-year-old female presented class III skeletal pattern. She had maxillary transverse deficiency with moderate crowding and posterior/anterior crossbites. Maxillary Skeletal Expander (MSE; Biomaterials Korea Inc.) type-2 was used as a MARPE device in this case. After four weeks of maxillary expansion, a significant amount of expansion was achieved and the anterior crossbite was spontaneously corrected. Fixed appliance treatment was commenced four weeks after MARPE with 0.022-slot preadjusted brackets (MBT prescription). Temporary anchorage devices (TADs) were placed over the mandibular buccal shelves for posterior teeth distalization and crowding relief. After 25 months of treatment, the facial profile was improved with maxillary advancement (SNA: 83° to 83.5°) and mandibular backward rotation (SNB: 83° to 82°; SN-MP: 34.5° to 35°). In this case, MARPE not only engenders significant transverse correction but also aids in anteroposterior change. The treatment effects of maxillary advancement and mandibular backward rotation can lead to a more esthetic profile in skeletal class III cases.

Ligand design for human acetylcholinesterase and nicotinic acetylcholine receptors, extending beyond the conventional and canonical.

We detail here distinctive departures from lead classical cholinesterase re-activators, the pyridinium aldoximes, to achieve rapid CNS penetration and reactivation of AChE in the CNS (brain and spinal cord). Such reactivation is consistent with these non-canonical re-activators enhancing survival parameters in both mice and macaques following exposure to organophosphates. Thus, the ideal cholinesterase re-activator should show minimal toxicity, limited inhibitory activity in the absence of an organophosphate, and rapid CNS penetration, in addition to its nucleophilic potential at the target, the conjugated AChE active center. These are structural properties directed to reactivity profiles at the conjugated AChE active center, reinforced by the pharmacokinetic and tissue disposition properties of the re-activator leads. In the case of nicotinic acetylcholine receptor (nAChR) agonists and antagonists, with the many existing receptor subtypes in mammals, we prioritize subtype selectivity in their design. In contrast to nicotine and its analogues that react with panoply of AChR subtypes, the substituted di-2-picolyl amine pyrimidines possess distinctive ionization characteristics reflecting in selectivity for the orthosteric site at the α7 subtypes of receptor. Here, entry to the CNS should be prioritized for the therapeutic objectives of the nicotinic agent influencing aberrant CNS activity in development or in the sequence of CNS ageing (longevity) in mammals, along with general peripheral activities controlling inflammation.

The Chromatin Remodelers PKL and PIE1 Act in an Epigenetic Pathway That Determines H3K27me3 Homeostasis in Arabidopsis.

Selective, tissue-specific gene expression is facilitated by the epigenetic modification H3K27me3 (trimethylation of lysine 27 on histone H3) in plants and animals. Much remains to be learned about how H3K27me3-enriched chromatin states are constructed and maintained. Here, we identify a genetic interaction in Arabidopsis thaliana between the chromodomain helicase DNA binding chromatin remodeler PICKLE (PKL), which promotes H3K27me3 enrichment, and the SWR1-family remodeler PHOTOPERIOD INDEPENDENT EARLY FLOWERING1 (PIE1), which incorporates the histone variant H2A.Z. Chromatin immunoprecipitation-sequencing and RNA-sequencing reveal that PKL, PIE1, and the H3K27 methyltransferase CURLY LEAF act in a common gene expression pathway and are required for H3K27me3 levels genome-wide. Additionally, H3K27me3-enriched genes are largely a subset of H2A.Z-enriched genes, further supporting the functional linkage between these marks. We also found that recombinant PKL acts as a prenucleosome maturation factor, indicating that it promotes retention of H3K27me3. These data support the existence of an epigenetic pathway in which PIE1 promotes H2A.Z, which in turn promotes H3K27me3 deposition. After deposition, PKL promotes retention of H3K27me3 after DNA replication and/or transcription. Our analyses thus reveal roles for H2A.Z and ATP-dependent remodelers in construction and maintenance of H3K27me3-enriched chromatin in plants.

Cost-effectiveness of early placement of vena cava filters to prevent symptomatic pulmonary embolism in patients with contraindications to prophylactic anticoagulant.

INTRODUCTION: Vena cava filters have been used as a primary means to prevent symptomatic pulmonary embolism (PE) in trauma patients who cannot be anticoagulated after severe injury, but the economic implications for this practice remain unclear. METHODS: Using a healthcare system perspective to analyze the a priori primary outcome of the da Vinci trial, we report the cost-effectiveness of using vena cava filters as a primary means to prevent PE in patients who have contraindications to prophylactic anticoagulation after major trauma. RESULTS: Of the 240 patients enrolled, complete, prospectively collected, hospital cost data during the entire hospital stay - including costs for the filter, medical/nursing/allied health staff, medical supplies, pathology tests, and radiological imaging - were available in 223 patients (93%). Patients allocated to the filter group (n = 114) were associated with a reduced risk of PE (0.9%) compared to those in the control group (n = 109, 5.5%; p = 0.048); and the filter's benefit was more pronounced among those who could not be anticoagulated within 7 days (filter: 0% vs control: 16%, Bonferroni-corrected p = 0.02). Overall, the cost needed to prevent one PE was high (AUD $379,760), but among those who could not be anticoagulated within 7 days, the costs to prevent one PE (AUD $36,156; ~ USD $26,032) and gain one quality-adjusted life-year (AUD $30,903; ~ USD $22,250) were substantially lower. CONCLUSION: The cost of using a vena cava filter to prevent PE for those who have contraindications to prophylactic anticoagulation within 3 days of injury is prohibitive, unless such contraindications remain for longer than 7 days. (Australian New Zealand Clinical Trials Registry no.: ACTRN12614000963628).

Intensive care doctors and nurses personal preferences for Intensive Care, as compared to the general population: a discrete choice experiment.

BACKGROUND: To test the hypothesis that Intensive Care Unit (ICU) doctors and nurses differ in their personal preferences for treatment from the general population, and whether doctors and nurses make different choices when thinking about themselves, as compared to when they are treating a patient. METHODS: Cross sectional, observational study conducted in 13 ICUs in Australia in 2017 using a discrete choice experiment survey. Respondents completed a series of choice sets, based on hypothetical situations which varied in the severity or likelihood of: death, cognitive impairment, need for prolonged treatment, need for assistance with care or requiring residential care. RESULTS: A total of 980 ICU staff (233 doctors and 747 nurses) participated in the study. ICU staff place the highest value on avoiding ending up in a dependent state. The ICU staff were more likely to choose to discontinue therapy when the prognosis was worse, compared with the general population. There was consensus between ICU staff personal views and the treatment pathway likely to be followed in 69% of the choices considered by nurses and 70% of those faced by doctors. In 27% (1614/5945 responses) of the nurses and 23% of the doctors (435/1870 responses), they felt that aggressive treatment would be continued for the hypothetical patient but they would not want that for themselves. CONCLUSION: The likelihood of returning to independence (or not requiring care assistance) was reported as the most important factor for ICU staff (and the general population) in deciding whether to receive ongoing treatments. Goals of care discussions should focus on this, over likelihood of survival.

A simplified (modified) Duke Activity Status Index (M-DASI) to characterise functional capacity: a secondary analysis of the Measurement of Exercise Tolerance before Surgery (METS) study.

BACKGROUND: Accurate assessment of functional capacity, a predictor of postoperative morbidity and mortality, is essential to improving surgical planning and outcomes. We assessed if all 12 items of the Duke Activity Status Index (DASI) were equally important in reflecting exercise capacity. METHODS: In this secondary cross-sectional analysis of the international, multicentre Measurement of Exercise Tolerance before Surgery (METS) study, we assessed cardiopulmonary exercise testing and DASI data from 1455 participants. Multivariable regression analyses were used to revise the DASI model in predicting an anaerobic threshold (AT) >11 ml kg-1 min-1 and peak oxygen consumption (VO2 peak) >16 ml kg-1 min-1, cut-points that represent a reduced risk of postoperative complications. RESULTS: Five questions were identified to have dominance in predicting AT>11 ml kg-1 min-1 and VO2 peak>16 ml.kg-1min-1. These items were included in the M-DASI-5Q and retained utility in predicting AT>11 ml.kg-1.min-1 (area under the receiver-operating-characteristic [AUROC]-AT: M-DASI-5Q=0.67 vs original 12-question DASI=0.66) and VO2 peak (AUROC-VO2 peak: M-DASI-5Q 0.73 vs original 12-question DASI 0.71). Conversely, in a sensitivity analysis we removed one potentially sensitive question related to the ability to have sexual relations, and the ability of the remaining four questions (M-DASI-4Q) to predict an adequate functional threshold remained no worse than the original 12-question DASI model. Adding a dynamic component to the M-DASI-4Q by assessing the chronotropic response to exercise improved its ability to discriminate between those with VO2 peak>16 ml.kg-1.min-1 and VO2 peak<16 ml.kg-1.min-1. CONCLUSIONS: The M-DASI provides a simple screening tool for further preoperative evaluation, including with cardiopulmonary exercise testing, to guide perioperative management.

Incidence of Antithrombin Deficiency and Anti-Cardiolipin Antibodies After Severe Traumatic Brain Injury: A Prospective Cohort Study.

BACKGROUND: Animal studies suggested that cerebral mitochondrial cardiolipin phospholipids were released after severe traumatic brain injury (TBI), contributing to the pathogenesis of thromboembolism. OBJECTIVES: To determine the incidence of anti-cardiolipin antibodies after severe TBI and whether this was related to the severity of TBI and development of venous thromboembolism. METHODS: Serial anti-cardiolipin antibodies, antithrombin levels, viscoelastic testing, and coagulation parameters were measured on admission, day-1, and between day-5 and day-7 in patients with severe TBI requiring intracranial pressure monitoring. RESULTS: Of the 40 patients included (85% male and median age 42 years), 7 (18%) had a raised Ig-G or Ig-M anti-cardiolipin antibody titer after TBI. Antithrombin levels were below the normal level-especially on day-0 and day-1-in 15 patients (38%), and 14 patients (38%) developed an increase in maximum clot firmness on the viscoelastic test in conjunction with elevations in fibrinogen concentration and platelet count. Four patients (10%) developed deep vein thrombosis, and 10 patients (25%) died, both of which were not significantly related to the presence of anti-cardiolipin antibodies (P = 0.619 and P = 0.638, respectively). CONCLUSIONS: A reduction in antithrombin level and development of anti-cardiolipin antibodies were not rare immediately after severe TBI; these abnormalities were followed by an increase in in vitro clot strength due to elevations in fibrinogen concentration and platelet count. The quantitative relationships between the development of anti-cardiolipin antibodies and severity of TBI or clinical thromboembolic events deserve further investigation.

Perioperative ADministration of Dexamethasone And blood Glucose concentrations in patients undergoing elective non-cardiac surgery - the randomised controlled PADDAG trial.

BACKGROUND: The hyperglycaemic effect of dexamethasone in diabetic and nondiabetic patients in the peri-operative period is unknown. OBJECTIVE: To assess the effect of a single dose of intra-operative dexamethasone on peri-operative blood glucose. DESIGN: Multicentre, stratified, randomised trial. SETTING: University hospitals in Australia and Hong Kong. PATIENTS: A total of 302 adults scheduled for elective, noncardiac and nonobstetric surgical procedures under general anaesthesia, stratified by diabetes mellitus status, were randomised to receive placebo, 4 or 8 mg dexamethasone administered intravenously after induction of anaesthesia. MAIN OUTCOME MEASURES: Maximum blood glucose within 24 h of surgery, and the interaction between glycated haemoglobin (HbA1c) and dexamethasone were the primary and secondary outcomes. RESULTS: The median [IQR] baseline blood glucose in the nondiabetes stratum in the placebo (n=81), 4 mg (n=81) and 8 mg dexamethasone (n=77) trial arms were respectively 5.3 [4.6 to 5.8], 5.0 [4.7 to 5.4] and 5.0 [4.2 to 5.9] mmol l-1. In the diabetes stratum these values were 6.6 [6.0 to 8.3]; (n=22), 6.1 [5.5 to 10.4]; (n=22) and 6.7 [5.6 to 8.3]; (n=19) mmol l-1. The median [IQR] maximum peri-operative blood glucose values in the nondiabetes stratum were 6.0 [5.3 to 6.8], 6.3 [5.5 to 7.3] and 6.3 [5.8 to 7.4] mmol l-1 in the control, dexamethasone 4 mg and dexamethasone 8 mg arms, respectively. In the diabetes stratum these values were 10.3 [8.1 to 12.4], 12.6 [10.3 to 18.3] and 13.6 [11.2 to 20.1] mmol l-1. There was a significant interaction between pre-operative HbA1c value and 8 mg dexamethasone: every 1% increment in HbA1c produced a 4.0 mmol l-1 elevation in maximal peri-operative glucose concentration. CONCLUSION: Dexamethasone 4 mg or 8 mg did not induce greater hyperglycaemia compared with placebo for nondiabetic and well controlled diabetic patients. Maximal peri-operative blood glucose concentrations in patients with diabetes were related to baseline HbA1c values in a concentration-dependent fashion after 8 mg of dexamethasone. TRIAL REGISTRATION: Australia and New Zealand Clinical Trials Registry (ACTRN12614001145695): URL: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=367272.