Evaluating cerium (IV) oxide nanoparticles membrane behaviour and related toxicity

Cerium (IV) oxide nanoparticles (CeO2 NPs or nano-ceria) are one of the most popular NPs used in both industry and medicine. Nowadays, CeO2 NPs could be considered as one of the NPs with better prospects for future applications in medicine. CeO2 NPs have the ability to change between oxidation states Ce(IV) and Ce(III) creating oxygen vacancies in their structure. This ability, in theory, could regulate oxidative stress (OS). However, there are many contradictory reports regarding the beneficial or adverse effects CeO2 NPs produce when internalised in the body. In addition, the mechanisms through which CeO2 NPs interact once internalised in the body are not yet totally understood. This thesis analyses the interaction between CeO2 NPs and phospholipids (DOPC, DOPG, DOPE, DOPA and DOPS) using a biosensor able to mimic the cellular membrane. The working electrode of the electrochemical sensing device (ESD) consists of a mercury coated platinum electrode (Hg/Pt electrode) where phospholipids are deposited. CeO2 NPs with different size and shapes (spheres, cubes, needles and dots) are synthesised using wet-chemical and hydrothermal methods. Also, coated CeO2 NPs were synthesised using PVP, PEG, dextran and the CeO2 NPs were treated with PBS. The NPs were characterised using TEM, SAED, EDX, XRD, DLS and Z-Potential. Results show the chemical behavior of the CeO2NPs is related to a large extent to the characteristics of the NPs surface, the characteristics of their dispersion media and the size of the NPs. CeO2 NPs (spheres, cubes, needles and dots) did not show an interaction with the phospholipid membrane (DOPC) when the system was under a continuous flow of phosphate saline buffer (PBS, pH 7.4) and citric-citrate buffer (CCB, pH 4.0, 5.0, 6.0). Nevertheless, an interaction was observed when the system was under a continuous flow of CCB (pH 3.0) and GLY (3.0). It was concluded that Ce3+ on the NPs surface can bind to the phosphate group of the phospholipid polar heads when the NPs are in GLY 3.0. Results also showed that citrate on the CeO2 NPs surface hampers the interaction with the phospholipid monolayer at pHs above 3.0. Additionally, at acidic pH (pH 3.0), the CeO2 NPs (spheres and cubes) were able to cross the phospholipid monolayer and directly interact with the Hg/Pt electrode showing a semiconductor effect. Needles, which were bigger in size, did not produce a semiconductor effect under the same conditions. The semiconductor effect decreases as size increases. The interaction of the coated CeO2 NPs with DOPC was found to be dependent on the coating agent. In this way, the interaction between DOPC and the NPs was produced by the coating agent, not the NPs. Finally, CeO2 showed to be inert when interacting with DOPA, DOPG and DOPE under a continuous flow of PBS. The only exception was the dots, which produced a significant interaction with DOPA under the same conditions

Partially Oxidised Boron Nitride As A 2D Nanomaterial For Nanofiltration Applications

Access to clean water has become increasingly scarce in recent years due to various factors, such as increasing population density, urbanisation, and inequality, among others.1 The development of new, inexpensive, and reliable methods for the removal of various impurities and toxins from water is therefore vital. In recent years, the emergence of nanofiltration (NF) membranes has become an exciting prospect for water purification. NF can be described as a type of filtration which exhibits separation characteristics in between reverse osmosis and ultrafiltration, and typically has molecular weight cut-offs in the region of 200–1000 Daltons.2,3 Various nanomaterials have been implemented in NF membranes, such as metal organic frameworks (MOFs), metal oxide nanoparticles and nanotubes.4–6 NF membranes based on 2D nanomaterials such as graphene and boron nitride (BN) have attracted significant interest due to the unique properties of 2D nanomaterials, most importantly their high surface-to-volume ratio, which leads to high adsorption capacity. In particular, BN is an attractive candidate for use in NF membranes as it is mechanically strong, inexpensive, and environmentally friendly. BN-based membranes have been the subject of numerous studies, with BN shown to be very effective in the removal of several water pollutants, including various dyes, that often can be leached into wastewater, from the textile industry

Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

Correction to: Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

The original version of this article unfortunately contained a mistake

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries