Ferroptosis Mediated Inflammation Promotes Pulmonary Hypertension.

BACKGROUND: Mitochondrial dysfunction, characterized by impaired lipid metabolism and heightened reactive oxygen species generation, results in lipid peroxidation and ferroptosis. Ferroptosis is an inflammatory mode of cell death that promotes complement activation and macrophage recruitment. In pulmonary arterial hypertension (PAH), pulmonary arterial endothelial cells exhibit cellular phenotypes that promote ferroptosis. Moreover, there is ectopic complement deposition and inflammatory macrophage accumulation in the pulmonary vasculature. However, the effects of ferroptosis inhibition on these pathogenic mechanisms and the cellular landscape of the pulmonary vasculature are incompletely defined. METHODS: Multiomics and physiological analyses evaluated how ferroptosis inhibition-modulated preclinical PAH. The impact of adeno-associated virus 1-mediated expression of the proferroptotic protein ACSL (acyl-CoA synthetase long-chain family member) 4 on PAH was determined, and a genetic association study in humans further probed the relationship between ferroptosis and pulmonary hypertension. RESULTS: Ferrostatin-1, a small-molecule ferroptosis inhibitor, mitigated PAH severity in monocrotaline rats. RNA-sequencing and proteomics analyses demonstrated that ferroptosis was associated with PAH severity. RNA-sequencing, proteomics, and confocal microscopy revealed that complement activation and proinflammatory cytokines/chemokines were suppressed by ferrostatin-1. In addition, ferrostatin-1 combatted changes in endothelial, smooth muscle, and interstitial macrophage abundance and gene activation patterns as revealed by deconvolution RNA-sequencing. Ferroptotic pulmonary arterial endothelial cell damage-associated molecular patterns restructured the transcriptomic signature and mitochondrial morphology, promoted the proliferation of pulmonary artery smooth muscle cells, and created a proinflammatory phenotype in monocytes in vitro. Adeno-associated virus 1-Acsl4 induced an inflammatory PAH phenotype in rats. Finally, single-nucleotide polymorphisms in 6 ferroptosis genes identified a potential link between ferroptosis and pulmonary hypertension severity in the Vanderbilt BioVU repository. CONCLUSIONS: Ferroptosis promotes PAH through metabolic and inflammatory mechanisms in the pulmonary vasculature.

Murine allogeneic CAR T cells integrated before or early after posttransplant cyclophosphamide exert antitumor effects.

Relapse limits the therapeutic efficacy both of chimeric antigen receptor (CAR) T cells and allogeneic hematopoietic cell transplantation (allo-HCT). Patients may undergo these therapies sequentially to prevent or treat relapsed malignancy. However, direct integration of the 2 therapies has been avoided over concerns for potential induction of graft-versus-host disease (GVHD) by allogeneic CAR T cells. We have shown in murine T-cell-replete MHC-haploidentical allo-HCT that suppressive mechanisms induced immediately after posttransplant cyclophosphamide (PTCy), given on days +3/+4, prevent GVHD induction by alloreactive T cells infused as early as day +5. Therefore, we hypothesized that allogeneic CAR T cells given in a similarly integrated manner in our murine MHC-haploidentical allo-HCT model may safely exert antitumor effects. Indeed, allogeneic anti-CD19 CAR T cells given early after (day +5) PTCy or even prior to (day 0) PTCy cleared leukemia without exacerbating the cytokine release syndrome occurring from the MHC-haploidentical allo-HCT or interfering with PTCy-mediated GVHD prevention. Meanwhile, CAR T-cell treatment on day +9 or day +14 was safe but less effective, suggesting a limited therapeutic window. CAR T cells infused before PTCy were not eliminated, but surviving CAR T cells continued to proliferate highly and expand despite PTCy. In comparison with infusion on day +5, CAR T-cell infusion on day 0 demonstrated superior clinical efficacy associated with earlier CAR T-cell expansion, higher phenotypic CAR T-cell activation, less CD4+CD25+Foxp3+ CAR T-cell recovery, and transcriptional changes suggesting increased activation of CD4+ CAR T cells and more cytotoxic CD8+ CAR T cells. This study provides mechanistic insight into PTCy's impact on graft-versus-tumor immunity and describes novel approaches to integrate CAR T cells and allo-HCT that may compensate for deficiencies of each individual approach.

Trem2 Agonist Reprograms Foamy Macrophages to Promote Atherosclerotic Plaque Stability-Brief Report.

BACKGROUND: Trem2 (triggering receptor on myeloid cells 2), a surface lipid receptor, is expressed on foamy macrophages within atherosclerotic lesions and regulates cell survival, proliferation, and anti-inflammatory responses. Studies examining the role of Trem2 in atherosclerosis have shown that deletion of Trem2 leads to impaired foamy macrophage lipid uptake, proliferation, survival, and cholesterol efflux. Thus, we tested the hypothesis that administration of a Trem2 agonist antibody (AL002a) to atherogenic mice would enhance macrophage survival and decrease necrotic core formation to improve plaque stability. METHODS: To model a therapeutic intervention approach, atherosclerosis-prone mice (Ldlr [low-density lipoprotein receptor]-/-) were fed a high-fat diet for 8 weeks, then transitioned to treatment with AL002a or isotype control for an additional 8 weeks while continuing on a high-fat diet. RESULTS: AL002a-treated mice had increased lesion size in both the aortic root and whole mount aorta, which correlated with an expansion of plaque macrophage area. This expansion was due to increased macrophage survival and proliferation in plaques. Importantly, plaques from AL002a-treated mice showed improved features of plaque stability, including smaller necrotic cores, increased fibrous caps, and greater collagen deposition. Single-cell RNA sequencing of whole aorta suspensions from isotype- and AL002a-treated atherosclerotic mice revealed that Trem2 agonism dramatically altered foamy macrophage transcriptome. This included upregulation of oxidative phosphorylation and increased expression of collagen genes. In vitro studies validated that Trem2 agonism with AL002a promoted foamy macrophage oxidized low-density lipoprotein uptake, survival, and cholesterol efflux. CONCLUSIONS: Trem2 agonism expands atherosclerotic plaque macrophages by promoting cell survival and proliferation but improves features of plaque stability by rewiring foamy macrophage function to enhance cholesterol efflux and collagen deposition.

Predicting cognitive scores from wearable-based digital physiological features using machine learning: data from a clinical trial in mild cognitive impairment.

BACKGROUND: Continuous assessment and remote monitoring of cognitive function in individuals with mild cognitive impairment (MCI) enables tracking therapeutic effects and modifying treatment to achieve better clinical outcomes. While standardized neuropsychological tests are inconvenient for this purpose, wearable sensor technology collecting physiological and behavioral data looks promising to provide proxy measures of cognitive function. The objective of this study was to evaluate the predictive ability of digital physiological features, based on sensor data from wrist-worn wearables, in determining neuropsychological test scores in individuals with MCI. METHODS: We used the dataset collected from a 10-week single-arm clinical trial in older adults (50-70 years old) diagnosed with amnestic MCI (N = 30) who received a digitally delivered multidomain therapeutic intervention. Cognitive performance was assessed before and after the intervention using the Neuropsychological Test Battery (NTB) from which composite scores were calculated (executive function, processing speed, immediate memory, delayed memory and global cognition). The Empatica E4, a wrist-wearable medical-grade device, was used to collect physiological data including blood volume pulse, electrodermal activity, and skin temperature. We processed sensors' data and extracted a range of physiological features. We used interpolated NTB scores for 10-day intervals to test predictability of scores over short periods and to leverage the maximum of wearable data available. In addition, we used individually centered data which represents deviations from personal baselines. Supervised machine learning was used to train models predicting NTB scores from digital physiological features and demographics. Performance was evaluated using "leave-one-subject-out" and "leave-one-interval-out" cross-validation. RESULTS: The final sample included 96 aggregated data intervals from 17 individuals. In total, 106 digital physiological features were extracted. We found that physiological features, especially measures of heart rate variability, correlated most strongly to the executive function compared to other cognitive composites. The model predicted the actual executive function scores with correlation r = 0.69 and intra-individual changes in executive function scores with r = 0.61. CONCLUSIONS: Our findings demonstrated that wearable-based physiological measures, primarily HRV, have potential to be used for the continuous assessments of cognitive function in individuals with MCI.

Selective Liquid-Liquid Extraction of Thorium(IV) from Rare-Earth Element Mixtures.

One of the major challenges in processing rare-earth element (REE) materials arises from the large amounts of radioactive thorium (Th) that are often found within REE minerals, encouraging enhanced metal separation procedures. We report here a study aimed at developing improved systems for REE processing with the goal of efficient extraction of Th(IV) from acidic solution. A tripodal ligand, TRPN-CMPO-Ph, was prepared that utilizes carbamoylmethylphosphine oxide (CMPO) chelators tethered to a tris(3-aminopropyl)amine (TRPN) capping scaffold. The ligand and its metal complexes were characterized by using elemental analysis, NMR, Fourier transform infrared spectroscopy, mass spectrometry, and luminescence spectroscopy. Using a liquid-liquid metal extraction protocol, TRPN-CMPO-Ph selectively extracts Th(IV) at an efficiency of 79% from a mixture of Th(IV), UO22+, and all rare-earth metal cations (except promethium) dissolved in nitric acid into an organic solvent. Th(IV) extraction selectivity is maintained upon extraction from a mixture that approximates a typical monazite leach solution containing several relevant lanthanide ions, including two ions at higher concentration relative to Th(IV). Comparative studies with a tris(2-aminoethyl)amine (TREN)-capped derivative are presented and support the need for a larger TRPN capping scaffold in achieving Th(IV) extraction selectivity.

Resuscitation on the field of play: a best-practice guideline from Resuscitation Council UK.

Sudden cardiac arrest (SCA) is the leading cause of sudden death in athletes during high-level, organised sport. Patient-related and event-related factors provide an opportunity for rapid intervention and the potential for high survival rates. The aim of this consensus was to develop a best-practice guideline for dedicated field-of-play medical teams responding to SCA during an organised sporting event. A task-and-finish group from Resuscitation Council UK identified a stakeholder group of relevant experts and cardiac arrest survivors in March and April 2022. Together, they developed a best-practice guideline using the best available evidence. A public consultation period further refined the guideline before it was finalised in December 2023. Any sudden collapse, without rapid recovery during sporting activity, should be considered an SCA until proven otherwise. Field-of-play medical teams should be empowered to access the collapsed athlete as soon as possible and perform initial essential interventions in situ. This includes a suggested minimum of three cycles of cardiopulmonary resuscitation and defibrillation in persistent shockable rhythms while other aspects of advanced life support are initiated. There should be careful organisation and practice of the medical response, including plans to transport athletes to dedicated facilities for definitive medical care. This best-practice guideline complements, rather than supersedes, existing resuscitation guidelines. It provides a clear approach to how to best treat an athlete with SCA and how to organise the medical response so treatments are delivered effectively and optimise outcomes.

FFAR4 regulates cardiac oxylipin balance to promote inflammation resolution in HFpEF secondary to metabolic syndrome.

Heart failure with preserved ejection fraction (HFpEF) is a complex clinical syndrome, but a predominant subset of HFpEF patients has metabolic syndrome (MetS). Mechanistically, systemic, nonresolving inflammation associated with MetS might drive HFpEF remodeling. Free fatty acid receptor 4 (Ffar4) is a GPCR for long-chain fatty acids that attenuates metabolic dysfunction and resolves inflammation. Therefore, we hypothesized that Ffar4 would attenuate remodeling in HFpEF secondary to MetS (HFpEF-MetS). To test this hypothesis, mice with systemic deletion of Ffar4 (Ffar4KO) were fed a high-fat/high-sucrose diet with L-NAME in their water to induce HFpEF-MetS. In male Ffar4KO mice, this HFpEF-MetS diet induced similar metabolic deficits but worsened diastolic function and microvascular rarefaction relative to WT mice. Conversely, in female Ffar4KO mice, the diet produced greater obesity but no worsened ventricular remodeling relative to WT mice. In Ffar4KO males, MetS altered the balance of inflammatory oxylipins systemically in HDL and in the heart, decreasing the eicosapentaenoic acid-derived, proresolving oxylipin 18-hydroxyeicosapentaenoic acid (18-HEPE), while increasing the arachidonic acid-derived, proinflammatory oxylipin 12-hydroxyeicosatetraenoic acid (12-HETE). This increased 12-HETE/18-HEPE ratio reflected a more proinflammatory state both systemically and in the heart in male Ffar4KO mice and was associated with increased macrophage numbers in the heart, which in turn correlated with worsened ventricular remodeling. In summary, our data suggest that Ffar4 controls the proinflammatory/proresolving oxylipin balance systemically and in the heart to resolve inflammation and attenuate HFpEF remodeling.

Machupo Virus with Mutations in the Transmembrane Domain and Glycosylation Sites of the Glycoprotein Is Attenuated and Immunogenic in Animal Models of Bolivian Hemorrhagic Fever.

Several highly pathogenic mammarenaviruses cause severe hemorrhagic and neurologic disease in humans for which vaccines and antivirals are limited or unavailable. New World (NW) mammarenavirus Machupo virus (MACV) infection causes Bolivian hemorrhagic fever in humans. We previously reported that the disruption of specific N-linked glycan sites on the glycoprotein (GPC) partially attenuates MACV in an interferon alpha/beta and gamma (IFN-α/ß and -γ) receptor knockout (R-/-) mouse model. However, some capability to induce neurological pathology still remained. The highly pathogenic Junin virus (JUNV) is another NW arenavirus closely related to MACV. An F427I substitution in the GPC transmembrane domain (TMD) rendered JUNV attenuated in a lethal mouse model after intracranial inoculation. In this study, we rationally designed and rescued a MACV containing mutations at two glycosylation sites and the corresponding F438I substitution in the GPC TMD. The MACV mutant is fully attenuated in IFN-α/ß and -γ R-/- mice and outbred guinea pigs. Furthermore, inoculation with this mutant MACV completely protected guinea pigs from wild-type MACV lethal challenge. Last, we found the GPC TMD F438I substitution greatly impaired MACV growth in neuronal cell lines of mouse and human origins. Our results highlight the critical roles of the glycans and the TMD on the GPC in arenavirus virulence, which provide insight into the rational design of potential vaccine candidates for highly pathogenic arenaviruses. IMPORTANCE For arenaviruses, the only vaccine available is the live attenuated Candid#1 vaccine, a JUNV vaccine approved in Argentina. We and others have found that the glycans on GPC and the F427 residue in the GPC TMD are important for virulence of JUNV. Nevertheless, mutating either of them is not sufficient for full and stable attenuation of JUNV. Using reverse genetics, we disrupted specific glycosylation sites on MACV GPC and also introduced the corresponding F438I substitution in the GPC TMD. This MACV mutant is fully attenuated in two animal models and protects animals from lethal infection. Thus, our studies highlight the feasibility of rational attenuation of highly pathogenic arenaviruses for vaccine development. Another important finding from this study is that the F438I substitution in GPC TMD could substantially affect MACV replication in neurons. Future studies are warranted to elucidate the underlying mechanism and the implication of this mutation in arenavirus neural tropism.

Glycoprotein N-linked glycans play a critical role in arenavirus pathogenicity.

Several arenaviruses cause hemorrhagic fevers in humans with high case fatality rates. A vaccine named Candid#1 is available only against Junin virus (JUNV) in Argentina. Specific N-linked glycans on the arenavirus surface glycoprotein (GP) mask important epitopes and help the virus evade antibody responses. However the role of GPC glycans in arenavirus pathogenicity is largely unclear. In a lethal animal model of hemorrhagic fever-causing Machupo virus (MACV) infection, we found that a chimeric MACV with the ectodomain of GPC from Candid#1 vaccine was partially attenuated. Interestingly, mutations resulting in acquisition of N-linked glycans at GPC N83 and N166 frequently occurred in late stages of the infection. These glycosylation sites are conserved in the GPC of wild-type MACV, indicating that this is a phenotypic reversion for the chimeric MACV to gain those glycans crucial for infection in vivo. Further studies indicated that the GPC mutant viruses with additional glycans became more resistant to neutralizing antibodies and more virulent in animals. On the other hand, disruption of these glycosylation sites on wild-type MACV GPC rendered the virus substantially attenuated in vivo and also more susceptible to antibody neutralization, while loss of these glycans did not affect virus growth in cultured cells. We also found that MACV lacking specific GPC glycans elicited higher levels of neutralizing antibodies against wild-type MACV. Our findings revealed the critical role of specific glycans on GPC in arenavirus pathogenicity and have important implications for rational design of vaccines against this group of hemorrhagic fever-causing viruses.

Compilation of 10 Years of MIRU-VNTR Data: Canadian National Tuberculosis Laboratory's Experience.

Tuberculosis is a significant cause of morbidity worldwide and is a priority at the provincial and federal levels in Canada. It is known that tuberculosis transmission networks are complex and span many years as well as different jurisdictions and countries. MIRU-VNTR is a universal tuberculosis genotyping method that utilizes a 24-loci pattern and it has shown promise in identifying inter and intrajurisdictional clusters within Canada. MIRU-VNTR data collected over 10 years from the National Reference Centre for Mycobacteriology (NRCM) were analyzed in this study. Some clusters were unique to a single province/territory, while others spanned multiple provinces and/or territories in Canada. The use of a universal laboratory test can enhance contact tracing, provide geographical information on circulating genotypes, and hence, aid in tuberculosis investigation by public health. The housing of all data on one platform, technical ease of the method, easy exchange of data between jurisdictions, and strong collaboration with laboratories and surveillance units at the provincial and federal levels have the potential to identify possible outbreaks in real time.

Metabolic regulation of macrophage proliferation and function in atherosclerosis.

PURPOSE OF REVIEW: Macrophage accumulation within atherosclerotic plaque is a primary driver of disease progression. However, recent advances in both phenotypic and functional heterogeneity of these cells have allowed for improved insight into potential regulation of macrophage function within lesions. In this review, we will discuss recent insights on macrophage heterogeneity, lipid processing, metabolism, and proliferation in atherosclerosis. Furthermore, we will identify outstanding questions in the field that are pertinent to future studies. RECENT FINDINGS: With the recent development of single-cell RNA sequencing, several studies have highlighted the diverse macrophage populations within plaques, including pro-inflammatory, anti-inflammatory, lipid loaded and tissue resident macrophages. Furthermore, new data has suggested that differential activation of metabolic pathways, including glycolysis and fatty acid oxidation, may play a key role in determining function. Recent works have highlighted that different populations retain varying capacity to undergo proliferation; regulating the proliferation pathway may be highly effective in reducing plaque in advanced lesions. SUMMARY: Macrophage populations within atherosclerosis are highly heterogeneous; differences in cytokine production, lipid handling, metabolism, and proliferation are seen between subpopulations. Understanding the basic cellular mechanisms that drive this heterogeneity will allow for the development of highly specific disease modulating agents to combat atherosclerosis.

Molecular Epidemiology of Mycobacterium tuberculosis To Describe the Transmission Dynamics Among Inuit Residing in Iqaluit Nunavut Using Whole-Genome Sequencing.

BACKGROUND: In the last decade, tuberculosis (TB) incidence among Inuit in the Canadian Arctic has been rising. Our aim was to better understand the transmission dynamics of TB in this remote region of Canada using whole-genome sequencing. METHODS: Isolates from patients who had culture-positive pulmonary TB in Iqaluit, Nunavut, between 2009 and 2015 underwent whole-genome sequencing (WGS). The number of transmission events between cases within clusters was calculated using a threshold of a ≤3 single nucleotide polymorphism (SNP) difference between isolates and then combined with detailed epidemiological data using a reproducible novel algorithm. Social network analysis of epidemiological data was used to support the WGS data analysis. RESULTS: During the study period, 140 Mycobacterium tuberculosis isolates from 135 cases were sequenced. Four clusters were identified, all from Euro-American lineage. One cluster represented 62% of all cases that were sequenced over the entire study period. In this cluster, 2 large chains of transmission were associated with 3 superspreading events in a homeless shelter. One of the superspreading events was linked to a nonsanctioned gambling house that resulted in further transmission. Shelter to nonshelter transmission was also confirmed. An algorithm developed for the determination of transmission events demonstrated very good reproducibility (κ score .98, 95% confidence interval, .97-1.0). CONCLUSIONS: Our study suggests that socioeconomic factors, namely residing in a homeless shelter and spending time in a gambling house, combined with the superspreading event effect may have been significant factors explaining the rise in cases in this predominantly Inuit Arctic community.

Feasibility, acceptability, and efficacy of online supportive care for individuals living with and beyond lung cancer: a systematic review.

PURPOSE: To examine the evidence of the feasibility, acceptability, and potential efficacy of online supportive care interventions for people living with and beyond lung cancer (LWBLC). METHODS: Studies were identified through searches of Medline, EMBASE, PsychINFO, and CINAHL databases using a structured search strategy. The inclusion criteria (1) examined the feasibility, acceptability, and/or efficacy of an online intervention aiming to provide supportive care for people living with and beyond lung cancer; (2) delivered an intervention in a single arm or RCT study pre/post design; (3) if a mixed sample, presented independent lung cancer data. RESULTS: Eight studies were included; two randomised controlled trials (RCTs). Included studies reported on the following outcomes: feasibility and acceptability of an online, supportive care intervention, and/or changes in quality of life, emotional functioning, physical functioning, and/or symptom distress. CONCLUSION: Preliminary evidence suggests that online supportive care among individuals LWBLC is feasible and acceptable, although there is little high-level evidence. Most were small pilot and feasibility studies, suggesting that online supportive care in this group is in its infancy. The integration of online supportive care into the cancer pathway may improve quality of life, physical and emotional functioning, and reduce symptom distress. Online modalities of supportive care can increase reach and accessibility of supportive care platforms, which could provide tailored support. People LWBLC display high symptom burden and unmet supportive care needs. More research is needed to address the dearth of literature in online supportive care for people LWBLC.

Clinical Efficacy of Brown Seaweeds Ascophyllum nodosum and Fucus vesiculosus in the Prevention or Delay Progression of the Metabolic Syndrome: A Review of Clinical Trials.

Metabolic syndrome (MetS) is a global public health problem affecting nearly 25.9% of the world population characterised by a cluster of disorders dominated by abdominal obesity, high blood pressure, high fasting plasma glucose, hypertriacylglycerolaemia and low HDL-cholesterol. In recent years, marine organisms, especially seaweeds, have been highlighted as potential natural sources of bioactive compounds and useful metabolites, with many biological and physiological activities to be used in functional foods or in human nutraceuticals for the management of MetS and related disorders. Of the three groups of seaweeds, brown seaweeds are known to contain more bioactive components than either red and green seaweeds. Among the different brown seaweed species, Ascophyllum nodosum and Fucus vesiculosus have the highest antioxidant values and highest total phenolic content. However, the evidence base relies mainly on cell line and small animal models, with few studies to date involving humans. This review intends to provide an overview of the potential of brown seaweed extracts Ascophyllum nodosum and Fucus vesiculosus for the management and prevention of MetS and related conditions, based on the available evidence obtained from clinical trials.

Optimized Timing of Post-Transplantation Cyclophosphamide in MHC-Haploidentical Murine Hematopoietic Cell Transplantation.

Post-transplantation cyclophosphamide (PTCy) reduces the risks of severe acute and chronic graft-versus-host disease (GVHD) after allogeneic hematopoietic cell transplantation (HCT). Yet, the standard clinical dose and timing of PTCy were partly extrapolated from MHC-matched skin allografting models and were partly empirical. Here we investigated the impact of differential dosing and timing of PTCy on its efficacy in preventing GVHD in a murine MHC-haploidentical HCT model. Administration of PTCy on days +3/+4 was superior to administration on days +1/+2, +5/+6, or +7/+8, whereas low-dose (10 mg/kg/day) PTCy on days +1/+2 actually led to accelerated death. Although the optimal timing of PTCy dosing was day +2 or +3 in the skin allografting models, in our MHC-haploidentical HCT model, PTCy on days +2/+3 was inferior to PTCy on days +3/+4 at lower doses. PTCy administered on days +3/+4, +4/+5, or +3/+5 were similarly efficacious. Single-day versus 2-day dosing schedules demonstrated that PTCy is maximally effective when given on day +4. Flow cytometric analysis showed that optimal PTCy dosing schedules both decreased alloreactive CD4+CD25-Foxp3- T cell proliferation at day +7 and allowed preferential CD4+CD25+Foxp3+ T cell reconstitution at day +21, suggesting that this combination may be a potential predictive biomarker of successful GVHD prevention by PTCy. These results show that the dose, timing, and cumulative exposure of PTCy all are critical for its efficacy in preventing GVHD. We are currently investigating the clinical relevance of these findings in a protocol seeking to optimize PTCy dose and timing and test these T cell endpoints as candidate biomarkers of successful GVHD prevention by PTCy.

Whole genome sequencing to study the phylogenetic structure of serotype a Haemophilus influenzae recovered from patients in Canada.

This study examined the phylogenetic structure of serotype a Haemophilus influenzae (Hia) isolates recovered from patients in Canada. Hia isolates from 490 separate patients and an American Type Culture Collection (ATCC) strain were analyzed by multilocus sequence typing (MLST), with 18 different sequence types (STs) identified. Most (85.7%) Hia patient isolates were typed as ST-23 and another 12.7% belonged to 14 different STs with 6, 5, or 4 MLST gene loci related to ST-23 (ST-23 complex). Core genome single-nucleotide variation phylogeny (SNVPhyl) on whole genome sequence (WGS) data of 121 Hia patient isolates representing all identified STs and the ATCC strain revealed 2 phylogenetic populations, with all the ST-23 complex isolates within 1 population. The other phylogenetic population contained only the ATCC strain and 3 patient isolates. Concatenated hitABC sequences retrieved from WGS data and analyzed by MEGA (Molecular Evolutionary Genetic Analysis) alignment confirmed the phylogeny obtained by SNVPhyl. The sodC gene was found only in isolates in the minor phylogenetic population. The 2 phylogenetic populations of the Canadian Hia isolates are similar to the 2 clonal divisions described for serotype b H. influenzae. Combining MLST, core SNVPhyl, and hitABC gene sequence alignment showed that most (99.4%) Canadian Hia patient isolates belonged to 1 major phylogenetic population.

Interassociation consensus recommendations for pitch-side emergency care and personal protective equipment for elite sport during the COVID-19 pandemic.

The COVID-19 pandemic has necessitated many novel responses in healthcare including sport and exercise medicine. The cessation of elite sport almost globally has had significant economic implications and resulted in pressure to resume sport in very controlled conditions. This includes protecting pitch-side medical staff and players from infection. The ongoing prevalence of SARS-CoV-2 and the desire to resume professional sport required urgent best practice guidelines to be developed so that sport could be resumed as safely as possible. This set of best practice recommendations assembles early evidence for managing SARS-CoV-2 and integrates expert opinion to provide a uniform and pragmatic approach to enhance on-field and pitch-side safety for the clinician and player. The nature of SARS-CoV-2 transmission creates new hazards during resuscitation and emergency care and procedures. Recommendations for the use and type of personal protective equipment during on-field or pitch-side emergency medical care is provided based on the clinical scenario and projected risk of viral transmission.

Two Beta-Phosphorylamide Compounds as Ligands for Sm3+, Eu3+, and Tb3+: X-ray Crystallography and Luminescence Properties.

This paper describes the synthesis of two beta-phosphorylamide ligands and their coordination chemistry with the Ln ions Tb3+, Eu3+, and Sm3+. Both the ligands and Ln complexes were characterized by IR, NMR, MS, and X-ray crystallography. The luminescence properties of the Tb3+ and Eu3+ complexes were also characterized, including the acquisition of lifetime decay curves. In the solid state, the Tb3+ and Sm3+ ligand complexes were found to have a 2:2 stoichiometry when analyzed by X-ray diffraction. In these structures, the Ln ion was bound by both oxygen atoms of each beta-phosphorylamide moiety of the ligands. The Tb3+ and Eu3+ complexes were modestly emissive as solutions in acetonitrile, with lifetime values that fell within typical ranges.

An Open-Source Plate Reader.

Microplate readers are foundational instruments in experimental biology and bioengineering that enable multiplexed spectrophotometric measurements. To enhance their accessibility, we here report the design, construction, validation, and benchmarking of an open-source microplate reader. The system features full-spectrum absorbance and fluorescence emission detection, in situ optogenetic stimulation, and stand-alone touch screen programming of automated assay protocols. The total system costs less than $3500, a fraction of the cost of commercial plate readers, and can detect the fluorescence of common dyes at concentrations as low as ∼10 nM. Functional capabilities were demonstrated in the context of synthetic biology, optogenetics, and photosensory biology: by steady-state measurements of ligand-induced reporter gene expression in a model of bacterial quorum sensing and by flavin photocycling kinetic measurements of a LOV (light-oxygen-voltage) domain photoreceptor used for optogenetic transcriptional activation. Fully detailed guides for assembling the device and automating it using the custom Python-based API (Application Program Interface) are provided. This work contributes a key technology to the growing community-wide infrastructure of open-source biology-focused hardware, whose creation is facilitated by rapid prototyping capabilities and low-cost electronics, optoelectronics, and microcomputers.