Unveiling Cellular Identities and Gene Expression Pathways in Overlapping Myocarditis and Myositis.

Immune checkpoint therapies can drive antitumor responses and benefit patients but can also induce life-threatening immune-related adverse events such as myocarditis and myositis. These immune-related adverse events are rare but carry substantial morbidity and mortality. In this issue, Siddiqui and colleagues use single-cell RNA and T-cell receptor sequencing to identify novel cellular subsets and propose various mechanisms that could contribute to the pathogenesis of immune checkpoint inhibitor-associated myocarditis and myositis. These new insights should help move the field toward the development of improved treatment and prevention options, ultimately improving patient outcomes. See related article by Siddiqui et al., p. 964 (1).

Ethical and societal aspects of radiological protection for offspring and next generations.

PURPOSE: Over the last decade or so, ethical and societal aspects of radiological protection have received increasing attention. This is also reflected in the publications of the International Commission on Radiological Protection (ICRP). The current paper aims at identifying relevant ethical and societal topics which should receive attention in the context of radiological protection for offspring and next generations. MATERIALS AND METHODS: We present a non-comprehensive review of the subject, based on presentation made at an ICRP workshop in Budapest in 2022. We first discuss the ethical values promoted by ICRP, and the application of these values in cases of (potential) pre-conceptual and prenatal radiation exposures. We then consider experience gained after the Fukushima accident indicating particular societal concerns about the health effects of such exposures. RESULTS AND CONCLUSIONS: Beneficence/non-maleficence, prudence, justice and dignity, the "core values" of the system of radiological protection have special roles to play when heritable and/or in utero effects are to be considered. Prudence, in particular, must be taken account of in view of the fact that solid scientific data in humans are largely lacking in this area, and it is necessary to rely on insights from animal experiments as well as theoretical considerations. As regards societal considerations, the perception of risk among (potentially) affected populations needs to be taken seriously. Accountability, transparency, and inclusivity, the "procedural values" promoted by ICRP for the practical implementation of the system of radiological protection play a central role in overcoming skepticism and creating trust. Stakeholder involvement should emphasize cooperation and dialogue, which allows for the joint evaluation of an exposure situation by experts and affected people.

Evaluating the genetic consequences of population subdivision as it unfolds and how to best mitigate them: A rare story about koalas.

The genetic consequences of the subdivision of populations are regarded as significant to long-term evolution, and research has shown that the scale and speed at which this is now occurring is critically reducing the adaptive potential of most species which inhabit human-impacted landscapes. Here, we provide a rare and, to our knowledge, the first analysis of this process while it is happening and demonstrate a method of evaluating the effect of mitigation measures such as fauna crossings. We did this by using an extensive genetic data set collected from a koala population which was intensely monitored during the construction of linear transport infrastructure which resulted in the subdivision of their population. First, we found that both allelic richness and effective population size decreased through the process of population subdivision. Second, we predicted the extent to which genetic drift could impact genetic diversity over time and showed that after only 10 generations the resulting two subdivided populations could experience between 12% and 69% loss in genetic diversity. Lastly, using forward simulations we estimated that a minimum of eight koalas would need to disperse from each side of the subdivision per generation to maintain genetic connectivity close to zero but that 16 koalas would ensure that both genetic connectivity and diversity remained unchanged. These results have important consequences for the genetic management of species in human-impacted landscapes by showing which genetic metrics are best to identify immediate loss in genetic diversity and how to evaluate the effectiveness of any mitigation measures.

The injury patterns, management and outcomes of retroperitoneal haemorrhage caused by lumbar arterial bleeding at a Level-1 Trauma Centre: A 10-year retrospective review.

PURPOSE: Haemorrhagic shock remains a leading preventable cause of death amongst trauma patients. Failure to identify retroperitoneal haemorrhage (RPH) can lead to irreversible haemorrhagic shock. The arteries of the middle retroperitoneal region (i.e., the 1st to 4th lumbar arteries) are complicit in haemorrhage into the retroperitoneal space. However, predictive injury patterns and subsequent management implications of haemorrhage secondary to bleeding of these arteries is lacking. MATERIALS AND METHODS: We performed a retrospective cohort study of patients diagnosed with retroperitoneal haemorrhage who presented to our Level-1 Trauma Centre (2009-2019). We described the associated injuries, management and outcomes relating to haemorrhage of lumbar arteries (L1-4) from this cohort to assess risk and management priorities in non-cavitary haemorrhage compared to RPH due to other causes. RESULTS: Haemorrhage of the lumbar arteries (LA) is associated with a higher proportion of lumbar transverse process (TP) fractures. Bleeding from branches of these vessels is associated with lower systolic blood pressure, increased incidence of massive transfusion, higher shock index, and a higher Injury Severity Score (ISS). A higher proportion of patients in the LA group underwent angioembolisation when compared to other causes of RPH. CONCLUSION: This study highlights the injury patterns, particularly TP fractures, in the prediction, early detection and management of haemorrhage from the lumbar arteries (L1-4). Compared to other causes of RPH, bleeding of the LA responds to early, aggressive haemorrhage control through angioembolisation. These injuries are likely best treated in Level-1 or Level-2 trauma facilities that are equipped with angioembolisation facilities or hybrid theatres to facilitate early identification and management of thoracolumbar bleeds.

Feasibility study of computational occupational dosimetry: evaluating a proof-of-concept in an endovascular and interventional cardiology setting.

Individual monitoring of radiation workers is essential to ensure compliance with legal dose limits and to ensure that doses are As Low As Reasonably Achievable. However, large uncertainties still exist in personal dosimetry and there are issues with compliance and incorrect wearing of dosimeters. The objective of the PODIUM (Personal Online Dosimetry Using Computational Methods) project was to improve personal dosimetry by an innovative approach: the development of an online dosimetry application based on computer simulations without the use of physical dosimeters. Occupational doses were calculated based on the use of camera tracking devices, flexible individualised phantoms and data from the radiation source. When combined with fast Monte Carlo simulation codes, the aim was to perform personal dosimetry in real-time. A key component of the PODIUM project was to assess and validate the methodology in interventional radiology workplaces where improvements in dosimetry are needed. This paper describes the feasibility of implementing the PODIUM approach in a clinical setting. Validation was carried out using dosimeters worn by Vascular Surgeons and Interventional Cardiologists during patient procedures at a hospital in Ireland. Our preliminary results from this feasibility study show acceptable differences of the order of 40% between calculated and measured staff doses, in terms of the personal dose equivalent quantity Hp(10), however there is a greater deviation for more complex cases and improvements are needed. The challenges of using the system in busy interventional rooms have informed the future needs and applicability of PODIUM. The availability of an online personal dosimetry application has the potential to overcome problems that arise from the use of current dosimeters. In addition, it should increase awareness of radiation protection among staff. Some limitations remain and a second phase of development would be required to bring the PODIUM method into operation in a hospital setting. However, an early prototype system has been tested in a clinical setting and the results from this two-year proof-of-concept PODIUM project are very promising for future development.

Personal dosimetry for positron emitters, and occupational exposures from clinical use of gallium-68.

The current status and issues regarding positron dosimetry in nuclear medicine are summarized. The suitability of the United Kingdom Health Security Agency extremity and eye beta-gamma personal thermoluminescence dosemeters are then considered. Monte Carlo modelling is performed to determine their responses and derive sets of calibration factors, along withHp(0.07) andHp(3) conversion coefficients, for carbon-11, nitrogen-13, oxygen-15, fluorine-18 and gallium-68 sources, which are commonly used in positron emission tomography (PET) computed tomography; data for these isotopes is assumed extrapolatable to other positron sources. It is found that the dosemeters are adequate for assessing exposures to PET radionuclides, even if their routine calibrations to caesium-137 were maintained. An idealized set of measurements representing gallium-68 exposure scenarios is then described, including reproducible mock-ups of individuals manipulating vials and syringes. Finally, a short case-study is presented that explores occupational doses during routine clinical use of gallium-68. The extremity dosemeter results demonstrated significant variations dependent upon the exposure conditions, with some seen to be comparatively large; whole-body and eye dose rates per activity were found to be lower. The importance of routine dose monitoring of workers is emphasized, with the need for a longer-termed follow-up study demonstrated.

Genetic analysis of multiple primary melanomas arising within the boundaries of congenital nevi depigmentosa.

Here, we present a rare case of a patient who developed multiple primary melanomas within the boundaries of two nevi depigmentosa. The melanomas were excised, and as a preventive measure, the remainder of the nevi depigmentosa were removed. We performed whole-exome sequencing on excised tissue from the nevus depigmentosus, adjacent normal skin, and saliva to explain this intriguing phenomenon. We also performed a GeneTrails Comprehensive Solid Tumor Panel analysis on one of the melanoma tissues. Genetic analysis revealed germline MC1R V92M and TYR R402Q polymorphisms and a MET E168D germline mutation that may have increased the risk of melanoma development. This genetic predisposition, combined with a patient-reported history of substantial sun exposure and sunburns, which were more severe within the boundaries of the nevi depigmentosa due to the lack of photoprotective melanin, produced numerous somatic mutations in the melanocytes of the nevi depigmentosa. Fitting with this paradigm for melanoma development in chronically sun-damaged skin, the patient's melanomas harbored somatic mutations in CDKN2A (splice site), NF1, and ATRX and had a tumor mutation burden in the 90-95th percentile for melanoma.

Non-invasive prediction of the mouse tibia mechanical properties from microCT images: comparison between different finite element models.

New treatments for bone diseases require testing in animal models before clinical translation, and the mouse tibia is among the most common models. In vivo micro-Computed Tomography (microCT)-based micro-Finite Element (microFE) models can be used for predicting the bone strength non-invasively, after proper validation against experimental data. Different modelling techniques can be used to estimate the bone properties, and the accuracy associated with each is unclear. The aim of this study was to evaluate the ability of different microCT-based microFE models to predict the mechanical properties of the mouse tibia under compressive load. Twenty tibiae were microCT scanned at 10.4 µm voxel size and subsequently compressed at 0.03 mm/s until failure. Stiffness and failure load were measured from the load-displacement curves. Different microFE models were generated from each microCT image, with hexahedral or tetrahedral mesh, and homogeneous or heterogeneous material properties. Prediction accuracy was comparable among models. The best correlations between experimental and predicted mechanical properties, as well as lower errors, were obtained for hexahedral models with homogeneous material properties. Experimental stiffness and predicted stiffness were reasonably well correlated (R2 = 0.53-0.65, average error of 13-17%). A lower correlation was found for failure load (R2 = 0.21-0.48, average error of 9-15%). Experimental and predicted mechanical properties normalized by the total bone mass were strongly correlated (R2 = 0.75-0.80 for stiffness, R2 = 0.55-0.81 for failure load). In conclusion, hexahedral models with homogeneous material properties based on in vivo microCT images were shown to best predict the mechanical properties of the mouse tibia.

Optimization of the failure criterion in micro-Finite Element models of the mouse tibia for the non-invasive prediction of its failure load in preclinical applications.

New treatments against osteoporosis require testing in animal models and the mouse tibia is among the most common studied anatomical sites. In vivo micro-Computed Tomography (microCT) based micro-Finite Element (microFE) models can be used for predicting the bone strength non-invasively, after proper validation against experiments. The aim of this study was to evaluate the ability of different microCT-based bone parameters and microFE models to predict tibial structural mechanical properties in compression. Twenty tibiae were scanned at 10.4 µm voxel size and subsequently tested in uniaxial compression at 0.03 mm/s until failure. Stiffness and failure load were measured from the load-displacement curves. Standard morphometric parameters were measured from the microCT images. The spatial distribution of bone mineral content (BMC) was evaluated by dividing the tibia into 40 regions. MicroFE models were generated by converting each microCT image into a voxel-based mesh with homogeneous isotropic material properties. Failure load was estimated by using different failure criteria, and the optimized parameters were selected by minimising the errors with respect to experimental measurements. Experimental and predicted stiffness were moderately correlated (R2 = 0.65, error = 14% ± 8%). Normalized failure load was best predicted by microFE models (R2 = 0.81, error = 9% ± 6%). Failure load was not correlated to the morphometric parameters and weakly correlated with some geometrical parameters (R2 < 0.37). In conclusion, microFE models can improve the current estimation of the mouse tibia structural properties and in this study an optimal failure criterion has been defined. Since it is a non-invasive method, this approach can be applied longitudinally for evaluating temporal changes in the bone strength.

The mortality rate from self-harm in Iran.

BACKGROUND: Self-harm-related death is one of the most unfortunate, tragic, and regrettable types of death owing to injuries with a variety of socio-economic and cultural causes. The study aimed to determine the trend in the mortality of self-harm by sex and age at national and provincial levels in Iran over a period of 26 years. METHODS: The Iran Death Registration System (DRS), cemetery databanks in Tehran and Esfahan, and the national population and housing censuses of Iran were used for this study. Using a growth model, the population was estimated in the age groups. Incompleteness, misalignment, and misclassification in the DRS were all considered and addressed accordingly. We used a spatio-temporal and Gaussian process regression model to estimate mortality rates in children and adults. RESULTS: Over the study period, 67,670 deaths were estimated owing to self-harm across the country. The overall age-standardized mortality rate decreased from 4.32 per 100,000 (95% unit interface (UI): 3.25-5.75) to 2.78 (2.15-3.59) per 100,000 between 1990 and 2015, a reduction of approximately 35.65%. The M/F ratio was 2.03:1 with an annual percent change of -2.38% and -1.37% for women and men, respectively. The annual self-harm mortality rate was higher among individuals aged 15-24 years, as well as it was more in men during the study period. CONCLUSION: Mortality from self-harm has declined over the study period in Iran. Higher rates in men and in population aged 15-24 years, with considerable variation by province, were the distinguishing features of self-harm. Iran needs to improve monitoring through a comprehensive multisectoral strategy; and most importantly, provide timely, effective and low-cost preventive interventions.

Predicting Drug Resistance Using Deep Mutational Scanning.

Drug resistance is a major healthcare challenge, resulting in a continuous need to develop new inhibitors. The development of these inhibitors requires an understanding of the mechanisms of resistance for a critical mass of occurrences. Recent genome editing technologies based on high-throughput DNA synthesis and sequencing may help to predict mutations resulting in resistance by testing large mutagenesis libraries. Here we describe the rationale of this approach, with examples and relevance to drug development and resistance in malaria.

Determinants for Efficient Editing with Cas9-Mediated Recombineering in Escherichia coli.

In E. coli, editing efficiency with Cas9-mediated recombineering varies across targets due to differences in the level of Cas9:gRNA-mediated DNA double-strand break (DSB)-induced cell death. We found that editing efficiency with the same gRNA and repair template can also change with target position, cas9 promoter strength, and growth conditions. Incomplete editing, off-target activity, nontargeted mutations, and failure to cleave target DNA even if Cas9 is bound also compromise editing efficiency. These effects on editing efficiency were gRNA-specific. We propose that differences in the efficiency of Cas9:gRNA-mediated DNA DSBs, as well as possible differences in binding of Cas9:gRNA complexes to their target sites, account for the observed variations in editing efficiency between gRNAs. We show that editing behavior using the same gRNA can be modified by mutating the gRNA spacer, which changes the DNA DSB activity. Finally, we discuss how variable editing with different gRNAs could limit high-throughput applications and provide strategies to overcome these limitations.

CRISPR/Cas9 recombineering-mediated deep mutational scanning of essential genes in Escherichia coli.

Deep mutational scanning can provide significant insights into the function of essential genes in bacteria. Here, we developed a high-throughput method for mutating essential genes of Escherichia coli in their native genetic context. We used Cas9-mediated recombineering to introduce a library of mutations, created by error-prone PCR, within a gene fragment on the genome using a single gRNA pre-validated for high efficiency. Tracking mutation frequency through deep sequencing revealed biases in the position and the number of the introduced mutations. We overcame these biases by increasing the homology arm length and blocking mismatch repair to achieve a mutation efficiency of 85% for non-essential genes and 55% for essential genes. These experiments also improved our understanding of poorly characterized recombineering process using dsDNA donors with single nucleotide changes. Finally, we applied our technology to target rpoB, the beta subunit of RNA polymerase, to study resistance against rifampicin. In a single experiment, we validate multiple biochemical and clinical observations made in the previous decades and provide insights into resistance compensation with the study of double mutants.

A checklist for trauma quality improvement meetings: A process improvement study.

BACKGROUND: Each year approximately five million people die from injuries. In countries where systems of trauma care have been introduced, death and disability have decreased. A major component of developed trauma systems is a trauma quality improvement (TQI) program and trauma quality improvement meeting (TQIM). Effective TQIMs improve trauma care by identifying and fixing problems. But globally, TQIMs are absent or unstructured in most hospitals providing trauma care. The aim of this study was to implement and evaluate a checklist for a structured TQIM. METHODS: This project was conducted as a prospective before-and-after study in four major trauma centres in India. The intervention was the introduction of a structured TQIM using a checklist, introduced with a workshop. This workshop was based on the World Health Organization (WHO) TQI Programs short course and resources, plus the developed TQIM checklist. Pre- and post-intervention data collection occurred at all meetings in which cases of trauma death were discussed. The primary outcome was TQIM Checklist compliance, defined by the discussion of, and agreement upon each of the following: preventability of death, identification of opportunities to improve care and corrective actions and a plan for closing the loop. RESULTS: There were 34 meetings in each phase, with 99 cases brought to the pre-intervention phase and 125 cases brought to the post-intervention phase. There was an increase in the proportion of cases brought to the meeting for which preventability of death was discussed (from 94% to 100%, p = 0.007) and agreed (from 7 to 19%, OR 3.7; 95% CI:1.4-9.4, p = 0.004) and for which a plan for closing the loop was discussed (from 2% to 18%, OR 10.9; 95% CI:2.5-47.6, p < 0.001) and agreed (from 2% to 18%, OR 10.9; 95% CI:2.5-47.6, p < 0.001). CONCLUSION: This study developed, implemented and evaluated a TQIM Checklist for improving TQIM processes. The introduction of a TQIM Checklist, with training, into four Indian trauma centres, led to more structured TQIMs, including increased discussion and agreement on preventability of death and plans for loop closure. A TQIM Checklist should be considered for all centres managing trauma patients.

Trend of fatal poisoning at national and provincial levels in Iran from 1990 to 2015.

OBJECTIVES: Comprehensive and up-to-date data on fatal injury trends are critical to identify challenges and plan priority setting. This study provides a comprehensive assessment of poisoning mortality trends across Iran. STUDY DESIGN: The data were gathered from various resources, including death registration systems, cemetery databases of Tehran and Esfahan, the Demographic and Health Survey of 2000, and three rounds of national population and housing censuses. METHODS: After addressing incompleteness for child and adult death data separately and using a spatio-temporal model and Gaussian process regression, the level and trend of child and adult mortality were estimated. For estimating cause-specific mortality, the cause fraction was calculated and applied to the level and trend of death. RESULTS: From 1990 to 2015, 40,586 deaths due to poisoning were estimated across the country. The poisoning-related age-standardized death rate per 100,000 was estimated to have changed from 3.08 (95% uncertainty interval [UI]: 2.32-4.11) in 1990 to 0.96 (95% UI: 0.73-1.25) in 2015, and the male/female ratio was 1.35 during 25 years of study with an annual percentage change of -5.4% and -4.0% for women and men, respectively. The annual mortality rate was higher among children younger than 5 years and the elderly population (≥70 years) in the study period. CONCLUSIONS: This study showed that mortality from poisoning declined in Iran over the period from 1990 to 2015 and varied by province. Understanding the reasons for the differences of poisoning mortality by province will help in developing and implementing measures to reduce this burden in Iran.

Genomic Deoxyxylulose Phosphate Reductoisomerase (DXR) Mutations Conferring Resistance to the Antimalarial Drug Fosmidomycin in E. coli.

Sequence to activity mapping technologies are rapidly developing, enabling the generation and isolation of mutations conferring novel phenotypes. Here we used the CRISPR enabled trackable genome engineering (CREATE) technology to investigate the inhibition of the essential ispC gene in its native genomic context in Escherichia coli. We created a full saturation library of 33 sites proximal to the ligand binding pocket and challenged this library with the antimalarial drug fosmidomycin, which targets the ispC gene product, DXR. This selection is especially challenging since it is relatively weak in E. coli, with multiple naturally occurring pathways for resistance. We identified several previously unreported mutations that confer fosmidomycin resistance, in highly conserved sites that also exist in pathogens including the malaria-inducing Plasmodium falciparum. This approach may have implications for the isolation of resistance-conferring mutations and may affect the design of future generations of fosmidomycin-based drugs.

Internet use among young people with and without mental health difficulties.

OBJECTIVES: Research regarding adolescent internet use and mental health is sparse. However, awareness of a young person's internet use is becoming increasingly recognised as an important element of clinical assessment and intervention, and requires the development of an evidence base. The aim of the present study was to better understand the internet use of young people experiencing mental health difficulties and to contrast it with those who currently report no concerns. METHOD: In total, 299 young people aged 12-19 years, across a continuum of mental health difficulties, completed an online survey measuring internet use and related experiences. Young people were assigned to four groups: (a) attending inpatient services; (b) attending outpatient services; (c) a community group with mental health concerns and no clinical support; and (d) a regular community group. RESULTS: Those in the inpatient and outpatient groups visited more potentially harmful websites. Young people attending inpatient and outpatient services showed aspects of both more risky and less risky use. The community group reporting no mental health difficulties showed least risky use. The group experiencing difficulties but not receiving support showed consistently high risky use, suggesting this is a particularly vulnerable group. CONCLUSIONS: Despite methodological limitations, findings suggest that those with mental health difficulties may experience more of the risks and fewer of the benefits offered by the internet. Though further research is needed to clarify these findings, clinicians should consider routine assessment of Internet use when planning interventions for young people experiencing mental health difficulties.

Experimental evaluation of new chitin-chitosan graft for duraplasty.

Natural materials such as collagen and alginate have promising applications as dural graft substitutes. These materials are able to restore the dural defect and create optimal conditions for the development of connective tissue at the site of injury. A promising material for biomedical applications is chitosan-a linear polysaccharide obtained by the deacetylation of chitin. It has been found to be nontoxic, biodegradable, biofunctional and biocompatible in addition to having antimicrobial characteristics. In this study we designed new chitin-chitosan substitutes for dura mater closure and evaluated their effectiveness and safety. Chitosan films were produced from 3 % of chitosan (molar mass-200, 500 or 700 kDa, deacetylation rate 80-90%) with addition of 20% of chitin. Antimicrobial effictively and cell viability were analysed for the different molar masses of chitosan. The film containing chitosan of molar mass 200 kDa, had the best antimicrobial and biological activity and was successfully used for experimental duraplasty in an in vivo model. In conclusion the chitin-chitosan membrane designed here met the requirements for a dura matter graft exhibiting the ability to support cell growth, inhibit microbial growth and biodegradade at an appropriate rate. Therefore this is a promising material for clinical duroplasty.

Management of haemodynamically stable patients with penetrating abdominal stab injuries: review of practice at an Australian major trauma centre.

INTRODUCTION: The management of haemodynamically stable patients who present following a penetrating abdominal injury (PAI) remains variable between mandatory surgical exploration and more selective non-operative approaches. The primary aim of this study was to assess compliance with an algorithm guiding selective non-operative management of haemodynamically stable patients with PAI. The secondary aim was to examine the association between compliance and unnecessary laparotomies. METHODS: This was a retrospective cohort study involving all patients with PAI that presented to a major trauma centre from January 2007 to December 2011. Data were extracted from the trauma registry and patients' electronic medical records. RESULTS: There were 189 patients included in the study, of which 79 (41.8 %) patients complied with the algorithm. The laparotomy rate in the setting of algorithm compliance was significantly lower than algorithm non-compliance (12.7 vs. 68.2 %; p < 0.01) as were unnecessary laparotomy rates (0 vs. 33.3 %; p = 0.03). CONCLUSION: Among haemodynamically stable patients presenting with PAI, compliance with an algorithm guiding selective non-operative management was low, but associated with lower laparotomy and lower unnecessary laparotomy rates. Improved compliance with algorithms directed towards selective non-operative management of PAI should be encouraged with stringent vigilance towards patient safety.

Innovations in the Use of Interactive Technology to Support Weight Management.

New and emerging mobile technologies are providing unprecedented possibilities for understanding and intervening on obesity-related behaviors in real time. However, the mobile health (mHealth) field has yet to catch up with the fast-paced development of technology. Current mHealth efforts in weight management still tend to focus mainly on short message systems (SMS) interventions, rather than taking advantage of real-time sensing to develop just-in-time adaptive interventions (JITAIs). This paper will give an overview of the current technology landscape for sensing and intervening on three behaviors that are central to weight management: diet, physical activity, and sleep. Then five studies that really dig into the possibilities that these new technologies afford will be showcased. We conclude with a discussion of hurdles that mHealth obesity research has yet to overcome and a future-facing discussion.