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Purpose: Pneumocystis jirovecii pneumonia (PJP) prophylaxis is required by provincial and national drug monographs during glioma treatment using temozolomide (TMZ) concurrently with radiation (TMZ-RT). However, real-world data suggest the potential benefits of PJP prophylaxis may not outweigh its potential harms in this population., Methods: We conducted a single-center patient survey and a national physician survey to explore the role of PJP prophylaxis amongst glioma patients undergoing TMZ-RT., Results: 23% (31/133) of physicians and 60% (44/73) of patients completed a survey. The median patient age was 42 (range 20-77); 85% (34/40) had completed adjuvant TMZ. Although only 2.4% (1/41) of patients received PJP prophylaxis, only one person (without PJP prophylaxis) was hospitalized for pneumonia. When presented with hypothetical PJP risks, 13.2% (5/38) of patients were concerned about PJP infection, while 26% (10/38) were concerned about potential side effects from prophylactic antibiotics. Most physicians (77%, 17/22) perceived the evidence for PJP prophylaxis as weak; 58% (11/19) did not routinely prescribe prophylaxis, and 73% (16/22) felt that PJP prophylaxis should be limited to patients with additional risk factors. Over 95% of physicians estimated that the incidence of PJP was < 1% in their last 5 years of practice regardless of PJP prophylaxis. For 73% (16/22) of physicians, to prescribe PJP prophylaxis, the risk of PJP infection needed to be 3-8%., Conclusion: The current recommendation to routinely prescribe PJP prophylaxis in patients receiving TMZ-RT in the absence of other risk factors warrants reconsideration., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Setting: Task sharing can fill health workforce gaps, improve access to care, and enhance health equity by redistributing health services to providers with less training. We report learnings from a demonstration project designed to assess whether lay student vaccinators can support community immunizations., Intervention: Between July 2022 and February 2023, 27 undergraduate and graduate students were recruited from the University of Toronto Emergency First Responders organization and operated 11 immunization clinics under professional supervision. Medical directives, supported with online and in-person training, enabled lay providers to administer and document vaccinations when supervised by nurses, physicians, or pharmacists. Participants were invited to complete a voluntary online survey to comment on their experience., Outcomes: Lay providers administered 293 influenza and COVID-19 vaccines without adverse events. A total of 141 participants (122 patients, 17 lay vaccinators, 1 nurse, and 1 physician) responded to our survey. More than 80% of patients strongly agreed to feeling safe and comfortable with lay providers administering vaccines under supervision, had no concerns with lay vaccinators, and would attend another lay vaccinator clinic. Content and thematic analysis of open-text responses revealed predominantly positive experiences, with themes about excellent vaccinators, organized and efficient clinics, and the importance of training, communication, and access to regulated professionals. The responding providers expressed comfort working in collaborative immunization teams., Implications: Lay student providers can deliver vaccines safely under a medical directive while potentially improving patient experiences. Rather than redeploying scarce professionals, task sharing strategies could position trained lay vaccinators to support immunizations, improve access, and foster community engagement., (© 2024. The Author(s).)

Hydrophobins are remarkable proteins due to their ability to self-assemble into amphipathic coatings that reverse surface wettability. Here, the versatility of the Class I hydrophobins EAS Δ15 and DewY in diverse nanosuspension and coating applications is demonstrated. The hydrophobins are shown to coat or emulsify a range of substrates including oil, hydrophobic drugs, and nanodiamonds and alter their solution and surface behavior. Surprisingly, while the coatings confer new properties, only a subset is found to be resistant to hot detergent treatment, a feature previously thought to be characteristic of the functional amyloid form of Class I hydrophobins. These results demonstrate that substrate surface properties can influence the molecular structures and physiochemical properties of hydrophobin and possibly other functional amyloids. Functional amyloid assembly with different substrates and conditions may be analogous to the propagation of different polymorphs of disease-associated amyloid fibrils with distinct structures, stability, and clinical phenotypes. Given that amyloid formation is not required for Class I hydrophobins to serve diverse applications, our findings open up new opportunities for their use in applications requiring a range of chemical and physical properties. In hydrophobin nanotechnological applications where high stability of assemblies is required, simultaneous structural and functional characterization should be carried out. Finally, while results in this study pertain to synthetic substrates, they raise the possibility that at least some members of the pseudo-Class I and Class III hydrophobins, reported to form assemblies with noncanonical properties, may be Class I hydrophobins adopting alternative structures in response to environmental cues.

Alzheimer's disease is imposing a growing social and economic burden worldwide, and effective therapies are urgently required. One possible approach to modulation of the disease outcome is to use small molecules to limit the conversion of monomeric amyloid (Aβ42) to cytotoxic amyloid oligomers and fibrils. We have synthesized modulators of amyloid assembly that are unlike others studied to date: these compounds act primarily by sequestering the Aβ42 monomer. We provide kinetic and nuclear magnetic resonance data showing that these perphenazine conjugates divert the Aβ42 monomer into amorphous aggregates that are not cytotoxic. Rapid monomer sequestration by the compounds reduces fibril assembly, even in the presence of pre-formed fibrillar seeds. The compounds are therefore also able to disrupt monomer-dependent secondary nucleation, the autocatalytic process that generates the majority of toxic oligomers. The inhibitors have a modular design that is easily varied, aiding future exploration and use of these tools to probe the impact of distinct Aβ42 species populated during amyloid assembly.

Direct catalytic decomposition of methane (CDM) has been studied as a possible emission-free hydrogen production route for over 100 years. However, the high cost of catalyst regeneration limits its practical applications. Here, we demonstrate that the solid by-product from CDM using Fe ore catalysts comprising carbon nano onions encapsulated with magnetic Fe cores (Fe@C) can serve as efficient and recyclable Fenton catalysts for pollutant degradation. Fe@C/H 2 O 2 has better performance than FeSO 4 /H 2 O 2 at similar Fe concentrations and can be used to decompose various pollutants. Mechanistic studies reveal that graphitic carbon layers and encapsulated Fe 0 contribute to their high catalytic activity. Further, Fe@C can be easily recovered from an aqueous solution and reused due to the encapsulated magnetic Fe particles. Over three reused cycles, Fe@C/H 2 O 2 only yields 1/8 of Fe sludges compared to FeSO 4 /H 2 O 2 , significantly reducing Fe sludge treatment costs. Overall, Fe@C demonstrates excellent application potentials in water and wastewater treatment, making H 2 production via CDM economically more viable., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Objective: To evaluate the effects of denosumab on erosion healing at 2-4 metacarpophalangeal (MCP) head as determined by high-resolution peripheral quantitative CT (HR-pQCT) in patients with rheumatoid arthritis (RA) with stable disease., Methods: This was a randomised, placebo-controlled, double-blind study. Patients with RA with disease activity score 28 joints (DAS28) ≤5.1 were randomised (1:1) to subcutaneous denosumab 60 mg or placebo once every 6 months for 24 months. The primary outcome was erosion healing at MCP 2-4 on HR-pQCT at 12 months. The effects of denosumab on erosion and joint space parameters on HR-pQCT and radiographs, disease activity and health assessment questionnaire-disability index (HAQ-DI) were also examined., Results: At 24 months, HR-pQCT images were analysed in 98 patients. One-third of the patients achieved sustained low disease activity throughout the study. At 12 months, changes in erosion parameters on HR-pQCT were similar between the two groups. At 24 months, new erosions (19% vs 9%, p=0.009) and erosion progression (18% vs 8%, p=0.019) were more common in the placebo group than the denosumab group. Erosion healing was seen in a significantly higher proportion of patients in the denosumab group (20% vs 6%, p=0.045) at 24 months. No significant changes in joint space parameters on HR-pQCT, van der Heijde-Sharp erosion score, DAS28 and HAQ-DI were observed in the two groups at 12 and 24 months., Conclusion: Although no differences in erosion parameters were observed at 12 months, denosumab was more efficacious than placebo in erosion repair on HR-pQCT after 24 months., Trial Registration Number: NCT03239080., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

The fungal hydrophobins are small proteins that are able to self-assemble spontaneously into amphipathic monolayers at hydrophobic:hydrophilic interfaces. These protein monolayers can reverse the wettability of a surface, making them suitable for increasing the biocompatibility of many hydrophobic nanomaterials. One subgroup of this family, the class I hydrophobins, forms monolayers that are composed of extremely robust amyloid-like fibrils, called rodlets. Here, we describe the protocols for the production and purification of recombinant hydrophobins and oxidative refolding to a biologically active, soluble, monomeric form. We describe methods to trigger the self-assembly into the fibrillar rodlet state and techniques to characterize the physicochemical properties of the polymeric forms.

Introduction: Cambodia's health equity fund (HEF) is the country's most significant social security scheme, covering the poorest one-fifth of the national population. During the last two decades, the HEF system was scaled up from an initial two health districts to national coverage of public health facilities. This is the first national study to examine the impact of the HEF on the utilisation of public health facilities., Methods: We first investigated the level of national HEF population coverage and health service use made by HEF eligible members using an administrative HEF operational dataset. Second, through multilevel interrupted time series analysis of routine monthly utilisation statistics during 2006-2013, we evaluated the impact of the HEF on hospital and health centre utilisation., Results: The proportion of HEF beneficiaries using hospital services in a given year (4.6%) appeared to exceed rates in the general population (3.3%). The introduction of the HEF was associated with: a significant level change in the monthly number of consultations at HCs followed by a gradual slope increase in time trend and a significant level change in the monthly number of deliveries. Overall, this was equivalent to a 15.6% net increase in number of consultations and 5.3% in deliveries in the first year. At RHs: a significant level change in the number of RH inpatient cases, followed by a sustained slope increase; a significant slope increase in the number of outpatient consultations and in the overall number of newborn deliveries. Overall, this was equivalent to a 47.9% net increase in inpatient cases, 24.1% in outpatient cases and 31.4% in deliveries in the first year., Conclusion: The implementation of the HEF scheme was associated with increased utilisation of primary and secondary care services by the poor., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Knowledge of the costs of health services improves health facility management and aids in health financing for universal health coverage. Because of resource requirements that are often not present in low- and middle-income countries, costing exercises are rare and infrequent. Here we report findings from the initial phase of establishing a routine costing system for health services implemented in three provinces in Cambodia., Methods: Data was collected for the 2016 financial year from 20 health centres (including four with beds) and five hospitals (three district hospitals and two provincial hospitals). The costs to the providers for health centres were calculated using step-down allocations for selected costing units, including preventive and curative services, delivery, and patient contact, while for hospitals this was complemented with bed-day and inpatient day per department. Costs were compared by type of facility and between provinces., Results: All required information was not readily available at health facilities and had to be recovered from various sources. Costs per outpatient consultation at health centres varied between provinces (from US$2.33 to US$4.89), as well as within provinces. Generally, costs were inversely correlated with the quantity of service output. Costs per contact were higher at health centres with beds than health centres without beds (US$4.59, compared to US$3.00). Conversely, costs for delivery were lower in health centres with beds (US$128.7, compared to US$413.7), mainly because of low performing health centres without beds. Costs per inpatient-day varied from US$27.61 to US$55.87 and were most expensive at the lowest level hospital., Conclusions: Establishing a routine health service costing system appears feasible if recording and accounting procedures are improved. Information on service costs by health facility level can provide useful information to optimise the use of available financial and human resources.

Background: Clinical trials management can be studied using project management theory. The CYCLE pilot randomized controlled trial (RCT) was conducted to determine the feasibility of a future rehabilitation trial of early in-bed cycling in the intensive care unit (ICU). In-bed cycling is a novel intervention, not typically available in ICUs. Implementation of this intervention requires personnel with specialized clinical expertise caring for critically ill patients and use of the in-bed cycle. Our objective was to describe the implementation and conduct of our pilot RCT using a project management approach., Methods: We retrospectively reviewed activities, timelines, and personnel involved in the trial. We organized activities into four project management phases: initiation, planning, execution, and monitoring and controlling. Data sources included Methods Centre documents used for trial coordination and conduct, and the trial data set. We report descriptive statistics as counts and proportions and also medians and quartiles, and we summarize the lessons learned., Results: Seven ICUs in Canada participated in the trial. Time from research ethics board and contracts submission to first enrolment was a median (first quartile, third quartile) of 185 (146, 209) and 162 (114, 181) days, respectively. We trained 128 personnel on the CYCLE pilot RCT protocol, and 80 (63%) completed trial-related activities. Four sites required additional training after start-up due to staff turnover and leaves of absence. Over 15 months, we screened 864 patients: 256 were eligible and 66 were enrolled. Despite an 85% consent rate, 74% (190/256) of eligible patients were not randomized, largely (80% [152/190]) due to physiotherapist availability. Thirteen percent of recruitment weeks were lost due to physiotherapist staffing shortages. We highlight five key lessons learned: (1) prepare and anticipate site needs; (2) communicate regularly; (3) proactively analyse and act on process measure data; (4) develop contingency plans; (5) express appreciation to participating sites., Conclusions: Our analysis highlights the scope of relevant activities, rigorous training and monitoring, number and types of required personnel, and time required to conduct a multicentre ICU rehabilitation intervention trial. Our lessons learned can help others interested in implementing complex intervention trials, such as rehabilitation., Trial Registration: ClinicalTrials.gov, NCT02377830 . Registered prospectively on 4 March 2015.

The rodlet structure present on the Aspergillus fumigatus conidial surface hides conidia from immune recognition. In spite of the essential biological role of the rodlets, the molecular basis for their self-assembly and disaggregation is not known. Analysis of the soluble forms of conidia-extracted and recombinant RodA by NMR spectroscopy has indicated the importance of disulfide bonds and identified two dynamic regions as likely candidates for conformational change and intermolecular interactions during conversion of RodA into the amyloid rodlet structure. Point mutations introduced into the RODA sequence confirmed that (1) mutation of a single cysteine was sufficient to block rodlet formation on the conidial surface and (2) both presumed amyloidogenic regions were needed for proper rodlet assembly. Mutations in the two putative amyloidogenic regions retarded and disturbed, but did not completely inhibit, the formation of the rodlets in vitro and on the conidial surface. Even in a disturbed form, the presence of rodlets on the surface of the conidia was sufficient to immunosilence the conidium. However, in contrast to the parental conidia, long exposure of mutant conidia lacking disulfide bridges within RodA or expressing RodA carrying the double (I115S/I146G) mutation activated dendritic cells with the subsequent secretion of proinflammatory cytokines. The immune reactivity of the RodA mutant conidia was not due to a modification in the RodA structure, but to the exposure of different pathogen-associated molecular patterns on the surface as a result of the modification of the rodlet surface layer. The full degradation of the rodlet layer, which occurs during early germination, is due to a complex array of cell wall bound proteases. As reported earlier, this loss of the rodlet layer lead to a strong anti- fumigatus host immune response in mouse lungs., (© 2019 The Authors.)

Introduction: Acute rehabilitation in critically ill patients can improve post-intensive care unit (post-ICU) physical function. In-bed cycling early in a patient's ICU stay is a promising intervention. The objective of this study was to determine the feasibility of recruitment, intervention delivery and retention in a multi centre randomised clinical trial (RCT) of early in-bed cycling with mechanically ventilated (MV) patients., Methods: We conducted a pilot RCT conducted in seven Canadian medical-surgical ICUs. We enrolled adults who could ambulate independently before ICU admission, within the first 4 days of invasive MV and first 7 days of ICU admission. Following informed consent, patients underwent concealed randomisation to either 30 min/day of in-bed cycling and routine physiotherapy (Cycling) or routine physiotherapy alone (Routine) for 5 days/week, until ICU discharge. Our feasibility outcome targets included: accrual of 1-2 patients/month/site; >80% cycling protocol delivery; >80% outcomes measured and >80% blinded outcome measures at hospital discharge. We report ascertainment rates for our primary outcome for the main trial (Physical Function ICU Test-scored (PFIT-s) at hospital discharge)., Results: Between 3/2015 and 6/2016, we randomised 66 patients (36 Cycling, 30 Routine). Our consent rate was 84.6 % (66/78). Patient accrual was (mean (SD)) 1.1 (0.3) patients/month/site. Cycling occurred in 79.3% (146/184) of eligible sessions, with a median (IQR) session duration of 30.5 (30.0, 30.7) min. We recorded 43 (97.7%) PFIT-s scores at hospital discharge and 37 (86.0%) of these assessments were blinded., Discussion: Our pilot RCT suggests that a future multicentre RCT of early in-bed cycling for MV patients in the ICU is feasible., Trial Registration Number: NCT02377830., Competing Interests: Competing interests: Restorative Therapies (Baltimore, MD) provided 2 RT-300 supine cycle ergometers for Toronto General Hospital and London Health Sciences sites for this research.

In recent years, much attention has focused on incorporating biological and bio-inspired nanomaterials into various applications that range from functionalising surfaces and enhancing biomolecule binding properties, to coating drugs for improved bioavailability and delivery. Hydrophobin proteins, which can spontaneously assemble into amphipathic layers at hydrophobic:hydrophilic interfaces, are exciting candidates for use as nanomaterials. These unique proteins, which are only expressed by filamentous fungi, have been the focus of increasing interest from the biotechnology industry, as evidenced by the sharply growing number of hydrophobin-associated publications and patents. Here, we explore the contribution of different hydrophobins to supporting fungal growth and development. We describe the key structural elements of hydrophobins and the molecular characteristics that underlie self-assembly of these proteins at interfaces. We outline the multiple roles that hydrophobins can play in supporting aerial growth of filamentous structures, facilitating spore dispersal and preventing an immune response in the infected host. The growing understanding of the hydrophobin protein structure and self-assembly process highlights the potential for hydrophobin proteins to be engineered for use in a variety of novel applications that require biocompatible coatings.

Hydrophobins are amphiphilic proteins secreted by filamentous fungi in a soluble form, which can self-assemble at hydrophilic/hydrophobic or water/air interfaces to form amphiphilic layers that have multiple biological roles. We have investigated the conformational changes that occur upon self-assembly of six hydrophobins that form functional amyloid fibrils with a rodlet morphology. These hydrophobins are present in the cell wall of spores from different fungal species. From available structures and NMR chemical shifts, we established the secondary structures of the monomeric forms of these proteins and monitored their conformational changes upon amyloid rodlet formation or thermal transitions using synchrotron radiation circular dichroism and Fourier-transform infrared spectroscopy (FT-IR). Thermal transitions were followed by synchrotron radiation circular dichroism in quartz cells that allowed for microbubbles and hence water/air interfaces to form and showed irreversible conformations that differed from the rodlet state for most of the proteins. In contrast, thermal transitions on hermetic calcium fluoride cells showed reversible conformational changes. Heating hydrophobin solutions with a water/air interface on a silicon crystal surface in FT-IR experiments resulted in a gain in β-sheet content typical of amyloid fibrils for all except one protein. Rodlet formation was further confirmed by electron microscopy. FT-IR spectra of pre-formed hydrophobin rodlet preparations also showed a gain in β-sheet characteristic of the amyloid cross-β structure. Our results indicate that hydrophobins are capable of significant conformational plasticity and the nature of the assemblies formed by these surface-active proteins is highly dependent on the interface at which self-assembly takes place., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

A panel of iridium(iii) porphyrin complexes containing axial N-heterocyclic carbene (NHC) ligand(s) were synthesized and characterized. X-ray crystal structures of the bis-NHC complexes [Ir III (ttp)(IMe) 2 ] + ( 2a ), [Ir III (oep)(BIMe) 2 ] + ( 2d ), [Ir III (oep)(I i Pr) 2 ] + ( 2e ) and [Ir III (F 20 tpp)(IMe) 2 ] + ( 2f ) display ruffled porphyrin rings with mesocarbon displacements of 0.483-0.594 Å and long Ir-C NHC bonds of 2.100-2.152 Å. Variable-temperature 1 H NMR analysis of 2a reveals that the macrocycle porphyrin ring inversion takes place in solution with an activation barrier of 40 ± 1 kJ mol -1 . The UV-vis absorption spectra of Ir III (por)-NHC complexes display split Soret bands. TD-DFT calculations and resonance Raman experiments show that the higher-energy Soret band is derived from the 1 MLCT dπ(Ir) → π*(por) transition. The near-infrared phosphorescence of Ir III (por)-NHC complexes from the porphyrin-based 3 (π, π*) state features broad emission bands at 701-754 nm with low emission quantum yields and short lifetimes ( Φ em < 0.01; τ < 4 μs). [Ir III (por)(IMe) 2 ] + complexes (por = ttp and oep) are efficient photosensitizers for 1 O 2 generation ( Φ so = 0.64 and 0.88) and are catalytically active in the light-induced aerobic oxidation of secondary amines and arylboronic acid. The bis-NHC complexes exhibit potent dark cytotoxicity towards a panel of cancer cells with IC 50 values at submicromolar levels. The cytotoxicity of these complexes could be further enhanced upon light irradiation with IC 50 values as low as nanomolar levels in association with the light-induced generation of reactive oxygen species (ROS). Bioimaging of [Ir III (oep)(IMe) 2 ] + ( 2c ) treated cells indicates that this Ir complex mainly targets the endoplasmic reticulum. [Ir III (oep)(IMe) 2 ] + catalyzes the photoinduced generation of singlet oxygen and triggers protein oxidation, cell cycle arrest, apoptosis and the inhibition of angiogenesis. It also causes pronounced photoinduced inhibition of tumor growth in a mouse model of human cancer.

We investigated how lateral erosion control, measured by novel photogrammetry techniques, is modified by the presence of Spartina spp. vegetation, sediment grain size, and the nutrient status of salt marshes across 230 km of the Italian Northern Adriatic coastline. Spartina spp. vegetation reduced erosion across our study sites. The effect was more pronounced in sandy soils, where erosion was reduced by 80% compared to 17% in silty soils. Erosion resistance was also enhanced by Spartina spp. root biomass. In the absence of vegetation, erosion resistance was enhanced by silt content, with mean erosion 72% lower in silty vs. sandy soils. We found no relevant relationships with nutrient status, likely due to overall high nutrient concentrations and low C:N ratios across all sites. Our results contribute to quantifying coastal protection ecosystem services provided by salt marshes in both sandy and silty sediments., (Copyright © 2017 Elsevier Ltd. All rights reserved.)