Among the emerging techniques to detect the real footprint of buried ore deposits is isotope tracing. Novel and automated preparation systems such as continuous flow isotope ratio mass spectrometry, off-axis integrated cavity output spectroscopy for isotopic compositions of selected molecules, multi-collector inductively coupled-plasma mass spectrometry (ICP-MS), triple quadrupole ICP-MS, laser ablation ICP-MS, and a multitude of inline preparation systems have facilitated the use of isotopes as tracers in mineral exploration, as costs for isotope analyses have decreased and the time required for the analyses has improved. In addition, the isotope systems being used have expanded beyond the traditional light stable and Pb isotopes to include a multitude of elements that behave differently during processes that promote the mobilization of elements during both primary and secondary dispersion. Isotopes are also being used to understand barren areas that lack a critical process to form an ore deposit and to reveal precise redox mechanisms. The goal is to be able to use isotopes to reflect a definitive process that occurs in association with the deposit and not in barren systems, and then to relate these to something that is easier to measure, namely elemental concentrations. As new generations of exploration and environmental scientists are becoming more comfortable with the application of isotopes to effectively trace processes involved in geoscience, and new technologies for rapid and inexpensive analyses of isotopes are continually being developed, novel applications of isotope tracing are becoming more mainstream.

Thematic collection: This article is part of the Exploration 17 collection available at: https://www.lyellcollection.org/cc/exploration-17

After vascular injury and exposure of subendothelial matrix proteins to the intravascular space, mediators of hemostasis are triggered and allow for clot formation and restoration of vascular integrity. Platelets are the mediators of primary hemostasis, creating a platelet plug and allowing for initial cessation of bleeding. Platelet disorders, qualitative and quantitative, may result in bleeding signs and symptoms, particularly mucocutaneous bleeding such as epistaxis, bruising, petechiae, and heavy menstrual bleeding. Increasing evidence suggests that platelets have functional capabilities beyond hemostasis, but this review focuses solely on platelet hemostatic properties. Herein, normal platelet function as well as the effects of abnormal function and thrombocytopenia are reviewed.

For manufacturers of both sterile and nonsterile pharmaceuticals, there is an expectation that the manufacturing process is performed in a manner that prevents extraneous contamination so that the products are provided in a safe, integral, pure, and unadulterated form. As part of that process, cleaning and disinfection are an absolute necessity. Although cleaning and disinfection support control of microbial contamination through preventive and corrective action, specific compendia methods do not currently exist. The intent of this paper is to provide a general guidance on how to perform disinfectant efficacy validation and implementation. This includes how to make sure the concepts are understood, how to interpret facility data and utilize it to demonstrate control awareness for your facilities, and how to leverage the data to reduce redundancies in validation or verification. This paper represents the thoughts and best practices of the authoring team and their respective companies and provides an efficient way to qualify disinfectants without impacting the quality of the study. If you choose to follow the recommendations in this paper, you must ensure that the appropriate rationale is sound and the scientific data is documented. It is the belief of the authoring team that only then will this approach meet regulatory requirements.

Pyrazinamide (PZA) is a cornerstone antimicrobial drug used exclusively for the treatment of tuberculosis (TB). Due to its ability to shorten drug therapy by 3 months and reduce disease relapse rates, PZA is considered an irreplaceable component of standard first-line short-course therapy for drug-susceptible TB and second-line treatment regimens for multidrug-resistant TB. Despite over 60 years of research on PZA and its crucial role in current and future TB treatment regimens, the mode of action of this unique drug remains unclear. Defining the mode of action for PZA will open new avenues for rational design of novel therapeutic approaches for the treatment of TB. In this review, we discuss the four prevailing models for PZA action, recent developments in modulation of PZA susceptibility and resistance, and outlooks for future research and drug development.

Physician-led thoracic ultrasound (TUS) has substantially changed how respiratory disorders, and in particular pleural diseases, are managed. The use of TUS as a point-of-care test enables the respiratory physician to quickly and accurately diagnose pleural pathology and ensure safe access to the pleural space during thoracentesis or chest drain insertion. Competence in performing TUS is now an obligatory part of respiratory speciality training programmes in different parts of the world. Pleural physicians with higher levels of competence routinely use TUS during the planning and execution of more sophisticated diagnostic and therapeutic interventions, such as core needle pleural biopsies, image-guided drain insertion and medical thoracoscopy. Current research is gauging the potential of TUS in predicting the outcome of different pleural interventions and how it can aid in tailoring the optimum treatment according to different TUS-based parameters.

Despite the importance of the Bering Sea for subarctic oceanography and climate, relatively little is known of the foraminifera from the extensive Aleutian Basin. We report the occurrence of modern deep-water agglutinated foraminifera collected at seven sites cored during Integrated Ocean Drilling Program (IODP) Expedition 323 in the Bering Sea. Assemblages collected from core-top samples contained 32 genera and 50 species and are described and illustrated here for the first time. Commonly occurring species include typical deep-water Rhizammina, Reophax, Rhabdammina, Recurvoides and Nodulina. Assemblages from the northern sites also consist of accessory Cyclammina, Eggerelloides and Glaphyrammina, whilst those of the Bowers Ridge sites consist of other tubular genera and Martinottiella. Of the studied stations with the lowest dissolved oxygen concentrations, the potentially Bering Sea endemic Eggerelloides sp. 1 inhabits the northern slope, which has the highest primary productivity, and the potentially endemic Martinottiella sp. 3 inhabits Bowers Ridge, which has the lowest oxygen concentrations but relatively low annual productivity. Martinottiella sp. 3, with open pores on its test surface, has previously been reported in Pliocene to Recent material from Bowers Ridge. Despite relatively small sample sizes, ecological constraints may imply that the Bering Sea experienced high productivity and reduced oxygen at times since at least the Pliocene. We note the partially endemic nature of the agglutinated foraminiferal assemblages, which may at least in part be due to basin restriction, the geologically long time period of reduced oxygen, and high organic carbon flux. Our results indicate the importance of gathering further surface sample data from the Aleutian Basin.

Planktonic foraminifera are a source of important geochemical, palaeoceanographic, and palaeontological data. However, many aspects of their ecology remain poorly understood, including whether or not gross morphology has an ecological function. Here, we measure the force needed to crush multiple planktonic foraminiferal morphotypes from modern core top and tow samples. We find significant differences in the resistance of different morphotypes to compressional force. Three species, Globorotalia tumida (biconvex, keeled), Menardella menardii (discoidal, keeled), Truncorotalia truncatulinoides (conical, keeled), require on average 59% more force (1.07 v. 0.47 N) to crush than the least resistant species (Orbulina universa and Trilobatus sacculifer) in core-top samples. Towed samples of pre-gametogenic individuals also show significant differences of the same magnitude (0.693 v. 0.53 N) between the conical (T. truncatulinoides) and globular/spherical morphologies (Globoconella inflata and O. universa). We hypothesize that the greater compressional strength of certain shapes confers a fitness advantage against predators and could contribute to the repeated, convergent evolution of keeled, conical and bi-convex forms in planktonic foraminifer lineages.

Supplementary material: Raw data for all crushing experiments, wall thickness measurements, and results for all pair-wise Kolmogorov-Smirnov Tests are available at https://doi.org/10.6084/m9.figshare.c.3725236.v1

New scanning electron microscope observations of unadulterated calcareous nannofossil assemblages on lamina surfaces of Cretaceous Tanzania Drilling Project sediments reveal high diversity in the <3 µm size-range and high abundances of small and frangible morphologies. These assemblages prompt comparison to modern assemblages, which show similar high diversity and abundance of very small and fragile taxa, although these assemblages are generally not preserved in the fossil record due to taphonomic filtering. Not only are there broad similarities between the general composition of modern assemblages and those of the Tanzanian lagerstätte, but also our discovery of several new Cretaceous taxa provides evidence for greatly extended fossil lineages of extant orders, with implications for both deep-time biodiversity divergence and survival through the end-Cretaceous mass extinction. Our findings include: new species that are the first-recorded Mesozoic representatives of the extant Syracosphaeraceae and Papposphaeraceae; potentially previously unrecorded diversity in the Mesozoic Calciosoleniaceae, another extant order, represented by extant species that have been described already; and new species and unusually high abundances of the Mesozoic Stephanolithiaceae. We also highlight the extended range of an incertae sedis Cenozoic genus, Ellipsolithus, into at least the Turonian.

Here, we describe seven new miniscule to very small Cretaceous species: Syracosphaera antiqua, S. repagula, Pocillithus macleodii, P. crucifer, Stradnerlithus wendleri, S.? haynesiae and Tortolithus foramen.

ABSTRACTIntroduction:Multimonth dispensing (MMD) of antiretroviral therapy (ART) is a differentiated model of care that can help overcome health system challenges and reduce the burden of HIV care on clients. Although 3-month dispensing has been the standard of care, interest has increased in extending refill intervals to 6 months. We explored client and provider experiences with MMD in Malawi as part of a cluster randomized trial evaluating 3- versus 6-month ART dispensing.Methods:Semi-structured in-depth interviews were conducted with 17 ART providers and 62 stable, adult clients with HIV on ART. Clients and providers were evenly divided by arm and were eligible for an interview if they had been participating in the study for 1 year (clients) or 6 months (providers). Questions focused on perceived challenges and benefits of the 3- or 6-month amount of ART dispensing. Interviews were transcribed, and data were coded and analyzed using constant comparison.Results:Both clients and providers reported that the larger medication supply had benefits. Clients reported decreased costs due to less frequent travel to the clinic and increased time for income-generating activities. Clients in the 6-month dispensing arm reported a greater sense of personal freedom and normalcy. Providers felt that the 6-month dispensing interval reduced their workload. They also expressed concerned about clients' challenges with ART storage at home, but clients reported no storage problems. Although providers mentioned the potential risk of clients sharing the larger medication supply with family or friends, clients emphasized the value of ART and reported only rare, short-term sharing, mostly with their spouses. Providers mentioned clients' lack of motivation to seek care for illnesses that might occur between refill appointments.Conclusions:The 6-month ART dispensing arm was particularly beneficial to clients for decreased costs, increased time for income generation, and a greater sense of normalcy. Providers' concerns about storage, sharing, and return visits to the facility did not emerge in client interviews. Further data are needed on the feasibility of implementing a large-scale program with 6-month dispensing.

OBJECTIVE

There is a controversy over the association between obesity and end-stage renal disease (ESRD) in people with or without type 2 diabetes; therefore, we examined the effect of BMI on the risk of ESRD according to glycemic status in the Korean population.

RESEARCH DESIGN AND METHODS

The study monitored 9,969,848 participants who underwent a National Health Insurance Service health checkup in 2009 from baseline to the date of diagnosis of ESRD during a follow-up period of ~8.2 years. Obesity was categorized by World Health Organization recommendations for Asian populations, and glycemic status was categorized into the following five groups: normal, impaired fasting glucose (IFG), newly diagnosed diabetes, diabetes <5 years, and diabetes ≥5 years.

RESULTS

Underweight was associated with a higher risk of ESRD in all participants after adjustment for all covariates. In the groups with IFG, newly diagnosed type 2 diabetes, diabetes duration <5 years, and diabetes ≥5 years, the hazard ratio (HR) of the underweight group increased with worsening glycemic status (HR 1.431 for IFG, 2.114 for newly diagnosed diabetes, 4.351 for diabetes <5 years, and 6.397 for diabetes ≥5 years), using normal weight with normal fasting glucose as a reference. The adjusted HRs for ESRD were also the highest in the sustained underweight group regardless of the presence of type 2 diabetes (HR 1.606 for nondiabetes and 2.14 for diabetes).

CONCLUSIONS

Underweight showed more increased HR of ESRD according to glycemic status and diabetes duration in the Korean population. These associations also persisted in the group with sustained BMI during the study period.

Interactions between platelets, leukocytes and the vessel wall provide alternative pathological routes of thrombo-inflammatory leukocyte recruitment. We found that when platelets were activated by a range of agonists in whole blood, they shed platelet-derived extracellular vesicles which rapidly and preferentially bound to blood monocytes compared to other leukocytes. Platelet-derived extracellular vesicle binding to monocytes was initiated by P-selectin-dependent adhesion and was stabilised by binding of phosphatidylserine. These interactions resulted in the progressive transfer of the platelet adhesion receptor GPIbα to monocytes. GPIbα^+-monocytes tethered and rolled on immobilised von Willebrand Factor or were recruited and activated on endothelial cells treated with TGF-β1 to induce the expression of von Willebrand Factor. In both models monocyte adhesion was ablated by a function-blocking antibody against GPIbα. Monocytes could also bind platelet-derived extracellular vesicle in mouse blood in vitro and in vivo. Intratracheal instillations of diesel nanoparticles, to model chronic pulmonary inflammation, induced accumulation of GPIbα on circulating monocytes. In intravital experiments, GPIbα⁺-monocytes adhered to the microcirculation of the TGF-β1-stimulated cremaster muscle, while in the ApoE^–/– model of atherosclerosis, GPIbα⁺-monocytes adhered to the carotid arteries. In trauma patients, monocytes bore platelet markers within 1 hour of injury, the levels of which correlated with severity of trauma and resulted in monocyte clearance from the circulation. Thus, we have defined a novel thrombo-inflammatory pathway in which platelet-derived extracellular vesicles transfer a platelet adhesion receptor to monocytes, allowing their recruitment in large and small blood vessels, and which is likely to be pathogenic.

The coordinated electrical activity of β-cells within the pancreatic islet drives oscillatory insulin secretion. A recent hypothesis postulates that specially equipped "hub" or "leader" cells within the β-cell network drive islet oscillations and that electrically silencing or optically ablating these cells suppresses coordinated electrical activity (and thus insulin secretion) in the rest of the islet. In this Perspective, we discuss this hypothesis in relation to established principles of electrophysiological theory. We conclude that whereas electrical coupling between β-cells is sufficient for the propagation of excitation across the islet, there is no obvious electrophysiological mechanism that explains how hyperpolarizing a hub cell results in widespread inhibition of islet electrical activity and disruption of their coordination. Thus, intraislet diffusible factors should perhaps be considered as an alternate mechanism.

BackgroundInfection is common in older adults. Serious infection has a high mortality rate and is associated with unplanned hospital admissions. Little is known about the factors that prompt older patients to seek medical advice when they may have an infection.AimTo explore the symptoms of infection from the perspective of older adults, and when and why older patients seek healthcare advice for a possible infection.Design and settingA qualitative interview study among adults aged ≥70 years with a clinical diagnosis of infection recruited from ambulatory care units in Oxford, UK.MethodInterviews were semi-structured and based on a flexible topic guide. Participants were given the option to be interviewed with their carer. Thematic analysis was facilitated using NVivo (version 11).ResultsA total of 28 participants (22 patients and six carers) took part. Patients (aged 70–92 years) had experienced a range of different infections. Several early non-specific symptoms were described (fever, feeling unwell, lethargy, vomiting, pain, and confusion/delirium). Internally minimising symptoms was common and participants with historical experience of infection tended to be better able to interpret their symptoms. Factors influencing seeking healthcare advice included prompts from family, specific or intolerable symptoms, symptom duration, and being unable to manage with self-care. For some, not wanting to be a burden affected their desire to seek help.ConclusionTailored advice to older adults highlighting early symptoms of infection may be beneficial. Knowing whether patients have had previous experience of infection may help healthcare professionals in assessing older patients with possible infection.

BackgroundIn the context of a variable condition such as asthma, patient recognition of deteriorating control and knowing what prompt action to take is crucial. Yet, implementation of recommended self-management strategies remains poor.AimTo explore how patients with asthma and parents/carers of children with asthma develop and establish recommended self-management strategies for living with asthma, and how clinicians can best support the process.Design and settingA qualitative study in UK primary care.MethodPatients with asthma and parents/carers of children with asthma from 10 general practices were purposively sampled (using age, sex, and duration of asthma) to participate in focus groups or interviews between May 2016 and August 2016. Participants’ experiences of health care, management of asthma, and views on supported self-management were explored. Interviews and focus group sessions were audio-recorded and transcribed verbatim. Iterative thematic analysis was conducted, guided by the research questions and drawing on habit theory in discussion with a multidisciplinary research team.ResultsA total of 49 participants (45 patients; 4 parents/carers) took part in 32 interviews and five focus groups. Of these, 11 reported using an action plan. Patients learnt how to self-manage over time, building knowledge from personal experience and other sources, such as the internet. Some regular actions, for example, taking medication, became habitual. Dealing with new or unexpected scenarios required reflective abilities, which may be supported by a tailored action plan.ConclusionPatients reported learning intuitively how to self-manage. Some regular actions became habitual; dealing with the unexpected required more reflective cognitive skills. In order to support implementation of optimal asthma self- management, clinicians should consider both these aspects of self-management and support, and educate patients proactively.

PURPOSE

The prognosis of older patients with dizziness in primary care is unknown. Our objective was to determine the prognosis and survival of patients with different subtypes and causes of dizziness.

METHODS

In a primary care prospective cohort study, 417 older adults with dizziness (mean age 79 years) received a full diagnostic workup in 2006-2008. A panel of physicians classified the subtype and primary cause of dizziness. Main outcome measures were mortality and dizziness-related impairment assessed at 10-year follow-up.

RESULTS

At 10-year follow-up 169 patients (40.5%) had died. Presyncope was the most common dizziness subtype (69.1%), followed by vertigo (41.0%), disequilibrium (39.8%), and other dizziness (1.7%). The most common primary causes of dizziness were cardiovascular disease (56.8%) and peripheral vestibular disease (14.4%). Multivariable adjusted Cox models showed a lower mortality rate for patients with the subtype vertigo compared with other subtypes (hazard ratio [HR] = 0.62; 95% CI, 0.40-0.96), and for peripheral vestibular disease vs cardiovascular disease as primary cause of dizziness (HR = 0.46; 95% CI, 0.25-0.84). After 10 years, 47.7% of patients who filled out the follow-up measurement experienced substantial dizziness-related impairment. No significant difference in substantial impairment was seen between different subtypes and primary causes of dizziness.

CONCLUSIONS

The 10-year mortality rate was lower for the dizziness subtype vertigo compared with other subtypes. Patients with dizziness primarily caused by peripheral vestibular disease had a lower mortality rate than patients with cardiovascular disease. Substantial dizziness-related impairment in older patients with dizziness 10 years later is high, and indicates that current treatment strategies by family physicians may be suboptimal.

Metabolic disorders are highly prevalent in kidney transplant candidates and recipients and can adversely affect post-transplant graft outcomes. Management of diabetes, hyperparathyroidism, and obesity presents distinct opportunities to optimize patients both before and after transplant as well as the ability to track objective data over time to assess a patient’s ability to partner effectively with the health care team and adhere to complex treatment regimens. Optimization of these particular disorders can most dramatically decrease the risk of surgical and cardiovascular complications post-transplant. Approximately 60% of nondiabetic patients experience hyperglycemia in the immediate post-transplant phase. Multiple risk factors have been identified related to development of new onset diabetes after transplant, and it is estimated that upward of 7%–30% of patients will develop new onset diabetes within the first year post-transplant. There are a number of medications studied in the kidney transplant population for diabetes management, and recent data and the risks and benefits of each regimen should be optimized. Secondary hyperparathyroidism occurs in most patients with CKD and can persist after kidney transplant in up to 66% of patients, despite an initial decrease in parathyroid hormone levels. Parathyroidectomy and medical management are the options for treatment of secondary hyperparathyroidism, but there is no randomized, controlled trial providing clear recommendations for optimal management, and patient-specific factors should be considered. Obesity is the most common metabolic disorder affecting the transplant population in both the pre- and post-transplant phases of care. Not only does obesity have associations and interactions with comorbid illnesses, such as diabetes, dyslipidemia, and cardiovascular disease, all of which increase morbidity and mortality post-transplant, but it also is intimately inter-related with access to transplantation for patients with kidney failure. We review these metabolic disorders and their management, including data in patients with kidney transplants.

Background and objectives

Walking while talking is a dual cognitive-motor task that predicts frailty, falls, and cognitive decline in the general elderly population. Adults with CKD have gait abnormalities during usual walking. It is unknown whether they have greater gait abnormalities and cognitive-motor interference during walking while talking.

Design, setting, participants, & measurements

Community-dwelling, nondisabled adults (n=330) ≥65 years of age underwent quantitative gait analysis, including walking while talking. Differences in walking-while-talking performance by CKD status were evaluated, and relative changes between walking-while-talking and walking alone performance were computed to quantify cognitive-motor interference (dual-task cost). Associations were tested using multivariable linear spline regression models, and independent gait domains were derived using factor analysis. CKD was defined as an eGFR<60 ml/min per 1.73 m².

Results

CKD was present in 134 (41%) participants. Participants with CKD had slower gait speed along with various gait cycle abnormalities during walking while talking: among those with CKD, every 10-ml/min per 1.73 m² lower eGFR was associated with 3.3-cm/s (95% confidence interval, 0.4 to 6.1) slower gait speed, 1.8-cm (95% confidence interval, 0.6 to 3.0) shorter step length, 1.1% (95% confidence interval, 0.6 to 1.7) less time in the swing phase, and 1.4% (95% confidence interval, 0.5 to 2.3) greater time in double support after multivariable adjustment. When comparing walking while talking with walking alone, every 10-ml/min per 1.73 m² lower eGFR was associated with 1.8% (95% confidence interval, 0.5 to 3.2) greater decrease in time in the swing phase and 0.9% (95% confidence interval, 0.2 to 1.5) greater increase in time in the stance phase. Factor analysis identified three walking-while-talking domains and three dual-task cost domains: eGFR was associated specifically with the rhythm domain for both walking-while-talking and dual-task cost. Every 10-ml/min per 1.73 m² lower eGFR was associated with a poorer performance of 0.2 SD (95% confidence interval, 0.1 to 0.3) for walking while talking and 0.2 SD (95% confidence interval, 0.03 to 0.3) for dual-task cost.

Conclusions

During walking while talking, CKD is associated with gait abnormalities, possibly due to increased cognitive-motor interference.

Background:

The negative effect of adverse childhood experiences (ACEs) on physical and mental health has led to calls for routine screening for ACEs in primary care settings. We aimed to examine the association between maternal ACEs and children’s behaviour problems (externalizing and internalizing) at age 5 in the context of other known predictors.

Methods:

We analyzed data from mother-and-child dyads participating in the All Our Families cohort in Calgary, Canada, between 2011 and 2017. Data were collected for factors related to the individual child (sex, age, temperament and behaviour), the mother (adverse childhood experiences, mental health, personality and parenting) and sociodemographic characteristics (family income, ethnicity and family structure) when the children were 3 and 5 years of age. We used logistic regression models to estimate crude and adjusted associations between maternal ACEs and children’s externalizing (hyperactivity and aggression) and internalizing (anxiety, depression and somatization) behaviours.

Results:

Data were available for 1688 mother-and-child dyads. In the crude models, the presence of 4 or more maternal ACEs was associated with children’s externalizing and internalizing behaviours at age 5. However, these associations were attenuated with adjustment. Persistent maternal mental health symptoms were associated with both externalizing and internalizing behaviours at age 5 (adjusted odds ratio [OR] 4.20, 95% confidence interval [CI] 2.50–7.05, and adjusted OR 2.52, 95% CI 1.66–3.81, respectively). High levels of ineffective parenting behaviours were also associated with both externalizing and internalizing behaviours at age 5 (adjusted OR 6.27, 95% CI 4.30–9.14, and adjusted OR 1.43, 95% CI 1.03–1.99, respectively).

Interpretation:

The association between maternal ACEs and children’s behaviour at age 5 was weakened in the presence of other maternal and family-level factors. Assessments of maternal mental health and parenting behaviours may be better targets for identifying children at risk of behavioural problems.

Background:

Previous studies examining potential sex and gender bias in the Canadian Resident Matching Service (CaRMS) match have had conflicting results. We examined the results of the CaRMS match over the period 2013–2019 to determine the potential association between applicants’ gender and the outcome of matching to their first-choice discipline.

Methods:

In this cross-sectional analysis, we determined the risk of matching to one’s first-choice discipline in CaRMS by applicant gender and year, for all Canadian medical students who participated in the first iteration of the R-1 match for the years 2013 to 2019. We analyzed data in 3 categories of disciplines according to CaRMS classifications: family medicine, nonsurgical disciplines and surgical disciplines. We excluded disciplines with fewer than 10 applicants.

Results:

Match results were available for 20 033 participants, of whom 11 078 (55.3%) were female. Overall, female applicants were significantly more likely to match to their first-choice discipline (relative risk [RR] 1.03, 95% confidence interval [CI] 1.02–1.04). After adjustment for match year and stratification by discipline categories, we found that female applicants were more likely to match to family medicine as their first choice (RR 1.04, 95% CI 1.03–1.05) and less likely to match to a first-choice surgical discipline (RR 0.95, 95% CI 0.91–1.00) than their male peers. There was no significant difference between the genders in matching to one’s first-choice nonsurgical discipline (RR 1.01, 95% CI 0.99–1.03).

Interpretation:

These results suggest an association between an applicant’s gender and the probability of matching to one’s first-choice discipline. The possibility of gender bias in the application process for residency programs should be further evaluated and monitored.

Background:

The number of medical undergraduate and postgraduate students completing palliative care clinical rotations in Canadian medical schools is currently unknown. The aim of this study was to assess the proportion of Canadian medical trainees completing clinical rotations in palliative care and to determine whether changes took place between 2008 and 2018.

Methods:

In this descriptive study, all Canadian medical schools (n = 17) were invited to provide data at the undergraduate and postgraduate levels (2007/08–2015/16 and 2007/08–2017/18, respectively). Information collected included the number, type and length of palliative care clinical rotations offered and the total number of medical trainees or residents enrolled at each school.

Results:

All 17 Canadian medical schools responded to the request for information. At the undergraduate level, palliative care clinical rotations were not offered in 2 schools, mandatory in 2 and optional in 13. Three schools that offered optional rotations were unable to provide complete data and were therefore excluded from further analyses. In 2015/16, only 29.7% of undergraduate medical students completed palliative care clinical rotations, yet this was a significant improvement compared to 2011/12 (13.6%, p = 0.02). At the postgraduate level, on average, 57.9% of family medicine trainees completed such rotations between 2007/08 and 2016/17. During the same period, palliative care clinical rotations were completed by trainees in specialty or subspecialty programs in anesthesiology (34.2%), geriatric medicine (64.4%), internal medicine (30.9%), neurology (28.2%) and psychiatry (64.5%).

Interpretation:

Between 2008 and 2018, a large proportion of Canadian medical trainees graduated without the benefit of a clinical rotation in palliative care. Without dedicated clinical exposure to palliative care, many physicians will enter practice without vital palliative care competencies.

The aim of this study was to assess the association of high-sensitivity cardiac troponin (hs-cTnT) and other cardiac, kidney, hyperglycemia, and inflammatory biomarkers with peripheral neuropathy (PN) in a community-based population.We conducted a cross-sectional analysis of 3056 black and white participants in the Atherosclerosis Risk in Communities (ARIC) study who underwent standardized monofilament PN testing and had measures of cardiac function (hs-cTnT, N-terminal pro–B-type natriuretic peptide [NT-proBNP], and growth differentiation factor 15 [GDF15]), kidney function (serum creatinine, cystatin C, β-2 microglobulin, urine albumin-to-creatinine ratio), hyperglycemia (fasting glucose, hemoglobin A_1c [Hb A_1c], fructosamine, glycated albumin, 1,5-anhydroglucitol), and inflammation (C-reactive protein) assessed at visit 6 (2016–2017; age 71–94 years). We used logistic regression to assess the associations of these biomarkers (modeled in diabetes-specific tertiles) with PN in older adults with and without diabetes after adjusting for traditional risk factors.In total, 33.5% of participants had PN (37.3% with diabetes and 31.9% without diabetes). There was an independent association of hs-cTnT with PN regardless of diabetes status (diabetes T3 vs. T1: odds ratio [OR], 2.15 [95% CI, 1.44–3.22]; no diabetes: OR, 2.31 [95%CI, 1.76–3.03]; P = 0.72 for interaction). Among participants without diabetes, there were also significant associations of NT-proBNP (OR, 1.40 [95% CI, 1.08–1.81]) and urine albumin-to-creatinine ratio (OR, 1.55 [95% CI, 1.22–1.97]) with PN. Associations of hyperglycemia biomarkers including Hb A_1c (OR, 1.76 [95% CI, 1.22–2.54]), fructosamine (OR, 1.71 [95% CI, 1.19–2.46]), and glycated albumin (OR, 1.45 [95% CI, 1.03–2.03]) with PN were significant only among participants with diabetes.Overall, hs-cTnT appears to be a global marker of end organ damage, including PN. Laboratory biomarkers may be able to help us identify those individuals with PN.

Hyponatremiahyposmolarreset osmostatsyndrome of inappropriate antidiuresiselderly

Lai et al. report the case of an elderly gentleman who presented with resolving neurologic findings from a transient ischemic attack and who was found to have hyponatremia with a serum sodium concentration of 123 mmol/L. Hypoosmolality was confirmed, and a diluting defect identified with a urine osmolality that ranged between 167 and 285 mOsm/kg. As the urine osmolality rose to > 400 mOsm/kg with water deprivation, a diagnosis of syndrome of inappropriate antidiuresis (SIAD) from reset osmostat was entertained.

Hyponatremia, the most common electrolyte disorder, is present in 2%–4% of ambulatory patients and up to 22% of geriatric inpatients (1). Clinicians classify hyponatremia into three main categories: hypovolemic (decreased intravascular volume from salt and water loss with inadequate replacement), euvolemic (normal intravascular volume, but increased water dilutes sodium), and hypervolemic (total body water is increased, usually causing edema, while intravascular volume is often decreased). Less frequent causes are pseudohyponatremia (due to decreased water in a fixed volume of plasma, usually due to increased lipids or protein) and water shifting due to increased osmolality (most commonly due to glucose). While the most extreme examples of hypovolemic and hypervolemic states can be determined by physical examination, in many cases the patient is euvolemic clinically.

Sleep and breathing disorders are highly prevalent, representing a growing subspecialty of respiratory medicine. The term sleep disordered breathing (SDB) encompasses a range of conditions characterised by abnormal breathing during sleep, from chronic or habitual snoring, to frank obstructive sleep apnoea (OSA) or, in some cases, central sleep apnoea (CSA) and hypoventilation syndromes. OSA is the commonest form of SDB, leading to many potential consequences and adverse clinical outcomes, including excessive daytime sleepiness, impaired daytime function, metabolic dysfunction, and an increased risk of cardiovascular disease and mortality [1]. The estimated reported prevalence of moderate-to-severe SDB (≥15 events·h^–1) was 23.4% in women and 49.7% in men, and the prevalence of symptomatic OSA was 9% and 13%, respectively [2]. However, in some populations, the prevalence of OSA is substantially higher, such as in patients been evaluated for bariatric surgery (estimated range 70–80%), in patients who have had a transient ischaemic attack or stroke (estimated range 60–70%) and in patients with cardiometabolic disease [3–6]. Limited data have been reported on CSA and non-obstructive sleep-related hypoventilation, which have received considerable interest in the sleep field within the past 10 years. Even if their prevalence was noted to be quite low relative to the prevalence of OSA [7], they are quite common in specific subpopulations [8–10].

Burkholderia cepacia (formerly Pseudomonas cepacia) was once thought to be a single bacterial species but has expanded to the Burkholderia cepacia complex (Bcc), comprising 24 closely related opportunistic pathogenic species. These bacteria have a widespread environmental distribution, an extraordinary metabolic versatility, a complex genome with three chromosomes, and a high capacity for rapid mutation and adaptation. Additionally, they present an inherent resistance to antibiotics and antiseptics, as well as the abilities to survive under nutrient-limited conditions and to metabolize the organic matter present in oligotrophic aquatic environments, even using certain antimicrobials as carbon sources. These traits constitute the reason that Bcc bacteria are considered feared contaminants of aqueous pharmaceutical and personal care products and the frequent reason behind nonsterile product recalls. Contamination with Bcc has caused numerous nosocomial outbreaks in health care facilities, presenting a health threat, particularly for patients with cystic fibrosis and chronic granulomatous disease and for immunocompromised individuals. This review addresses the role of Bcc bacteria as a potential public health problem, the mechanisms behind their success as contaminants of pharmaceutical products, particularly in the presence of biocides, the difficulties encountered in their detection, and the preventive measures applied during manufacturing processes to control contamination with these objectionable microorganisms. A summary of Bcc-related outbreaks in different clinical settings, due to contamination of diverse types of pharmaceutical products, is provided.

Chronic obstructive pulmonary disease (COPD) is an inflammatory lung condition, causing progressive decline in lung function leading to premature death. Acute exacerbations in COPD patients are predominantly associated with respiratory viruses. Ribavirin is a generic broad-spectrum antiviral agent that could be used for treatment of viral respiratory infections in COPD. Using the Particle Replication In Nonwetting Templates (PRINT) technology, which produces dry-powder particles of uniform shape and size, two new inhaled formulations of ribavirin (ribavirin-PRINT-CFI and ribavirin-PRINT-IP) were developed for efficient delivery to the lung and to minimize bystander exposure. Ribavirin-PRINT-CFI was well tolerated in healthy participants after single dosing and ribavirin-PRINT-IP was well tolerated in healthy and COPD participants after single and repeat dosing. Ribavirin-PRINT-CFI was replaced with ribavirin-PRINT-IP since the latter formulation was found to have improved physicochemical properties and it had a higher ratio of active drug to excipient per unit dose. Ribavirin concentrations were measured in lung epithelial lining fluid in both healthy and COPD participants and achieved target concentrations. Both formulations were rapidly absorbed with approximately dose proportional pharmacokinetics in plasma. Exposure to bystanders was negligible based on both the plasma and airborne ribavirin concentrations with the ribavirin-PRINT-IP formulation. Thus, ribavirin-PRINT-IP allowed for an efficient and convenient delivery of ribavirin to the lungs while minimizing systemic exposure. Further clinical investigations would be required to demonstrate ribavirin-PRINT-IP antiviral characteristics and impact on COPD viral-induced exacerbations. (The clinical trials discussed in this study have been registered at ClinicalTrials.gov under identifiers NCT03243760 and NCT03235726.)

Staphylococcus aureus biofilms are a significant problem in health care settings, partly due to the presence of a nondividing, antibiotic-tolerant subpopulation. Here we evaluated treatment of S. aureus UAMS-1 biofilms with HT61, a quinoline derivative shown to be effective against nondividing Staphylococcus spp. HT61 was effective at reducing biofilm viability and was associated with increased expression of cell wall stress and division proteins, confirming its potential as a treatment for S. aureus biofilm infections.

Cefiderocol inhibited 97.5% of 478 Gram-negative isolates from cancer patients at ≤4 mg/liter. It had potent activity against extended-spectrum β-lactamase-positive Enterobacteriaceae, carbapenem-resistant Enterobacteriaceae (CRE), and nonfermenting Gram-negative bacilli, including Pseudomonas aeruginosa, Stenotrophomonas maltophilia, and Acinetobacter species isolates. Amikacin, ceftazidime-avibactam, and meropenem had appreciable activity against non-CRE Enterobacteriaceae. No comparators were active against multidrug-resistant P. aeruginosa isolates. Only trimethoprim-sulfamethoxazole had appreciable activity against S. maltophilia isolates. Overall, cefiderocol was associated with the lowest level of resistance.

In the past few decades, enterovirus A71 (EVA71) has caused devastating outbreaks in the Asia-Pacific region, resulting in serious sequelae in infected young children. No preventive or therapeutic interventions are currently available for curing EVA71 infection, highlighting a great unmet medical need for this disease. Here, we showed that one novel single-domain antibody (sdAb), F1, isolated from an immunized llama, could alleviate EVA71 infection both in vitro and in vivo. We also confirmed that the sdAb clone F1 recognizes EVA71 through a novel conformational epitope comprising the highly conserved region of VP3 capsid protein by using competitive-binding and overlapping-peptide enzyme-linked immunosorbent assays (ELISAs). Because of the virion’s icosahedral structure, we reasoned that adjacent epitopes must be clustered within molecular ranges that may be simultaneously bound by an engineered antibody with multiple valency. Therefore, two single-domain binding modules (F1) were fused to generate an sdAb-in-tandem design so that the capture of viral antigens could be further increased by valency effects. We showed that the tetravalent construct F1xF1-hFc, containing two sdAb-in-tandem on a fragment crystallizable (Fc) scaffold, exhibits more potent neutralization activity against EVA71 than does the bivalent sdAb F1-hFc by at least 5.8-fold. We also demonstrated that, using a human scavenger receptor class B member 2 (hSCARB2) transgenic mouse model, a half dose of the F1xF1-hFc provided better protection against EVA71 infection than did the F1-hFc. Thus, our study furnishes important insights into multivalent sdAb engineering against viral infection and provides a novel strategic deployment approach for preparedness of emerging infectious diseases such as EVA71.

We characterized 29 bla_CTX-M-27-harboring plasmids of Escherichia coli sequence type 131 (ST131) sublineage C1/H30R isolates from healthy individuals and long-term-care facility (LTCF) residents. Most (27/29) plasmids were of the FIA, FIB, and FII multireplicon type with the same plasmid multilocus sequence typing (pMLST). Several plasmids (7/23) from LTCF residents harbored only bla_CTX-M-27 as the resistance gene; however, their fundamental structures were very similar to those of previously isolated bla_CTX-M-27/F1:A2:B20 plasmids, suggesting their prevalence as a newly arising public health concern.

HER2-targeted therapies are approved only for HER2-positive breast and gastric cancers. We assessed the safety/tolerability and activity of the novel HER2-targeted antibody–drug conjugate trastuzumab deruxtecan (T-DXd) in 60 patients with pretreated, HER2-expressing (IHC ≥ 1+), non-breast/non-gastric or HER2-mutant solid tumors from a phase I trial (NCT02564900). Most common (>50%) treatment-emergent adverse events (TEAE) were nausea, decreased appetite, and vomiting. Two drug-related TEAEs were associated with fatal outcomes. The confirmed objective response rate (ORR) was 28.3% (17/60). Median progression-free survival (PFS) was 7.2 [95% confidence interval (CI), 4.8–11.1] months. In HER2-mutant non–small cell lung cancer (NSCLC), ORR was 72.7% (8/11), and median PFS was 11.3 (95% CI, 8.1–14.3) months. Confirmed responses were observed in six tumor types, including HER2-expressing NSCLC, colorectal cancer, salivary gland cancer, biliary tract cancer, endometrial cancer, and HER2-mutant NSCLC and breast cancer. Results suggest T-DXd holds promise for HER2-expressing/mutant solid tumors.

Significance:

T-DXd demonstrated promising activity in a heterogeneous patient population with heavily pretreated HER2-expressing or HER2-mutant solid tumors, especially HER2-mutant NSCLC. The safety profile was generally acceptable. Interstitial lung disease can be severe and requires prompt monitoring and intervention. Further research of T-DXd is warranted to address these unmet medical needs.

See related commentary by Rolfo and Russo, p. 643.

This article is highlighted in the In This Issue feature, p. 627

Since 2018, the FDA has required that U.S. clinical trial results be reported to clinicaltrials.gov within a year of trial completion, but this mandate is often ignored. A recent study found that less than half of U.S. trials submitted results to the site by the deadline. Industry-led trials were the most likely to be reported on time.

In a draft guidance, the FDA urges researchers to take steps to increase enrollment of adults age 65 and older in clinical trials of investigational of cancer drugs. Noting that a drug's risk–benefit profile can vary significantly across age groups, the FDA recommends including older adults in early-phase studies and modifying trial designs and recruitment strategies to make it easier for them to participate.

Inflammasomes assemble in the cytosol of myeloid and epithelial cells on sensing of cellular stress and pathogen-associated molecular patterns and serve as scaffolds for recruitment and activation of inflammatory caspases. Inflammasomes play beneficial roles in host and immune responses against diverse pathogens but may also promote inflammatory tissue damage if uncontrolled. Gasdermin D (GSDMD) is a recently identified substrate of murine caspase-1 and caspase-11, and human caspases-1, -4, and -5 that mediates a regulated lytic cell death mode termed pyroptosis. Recent studies have identified pyroptosis as a critical inflammasome effector mechanism that controls inflammasome-dependent cytokine secretion and contributes to antimicrobial defense and inflammasome-mediated autoinflammatory diseases. Here, we review recent developments on inflammasome-associated effector functions with an emphasis on the emerging roles of gasdermin pores and pyroptosis.

To date, more than 200 monogenic, often devastating, skin diseases have been described. Because of unmet medical needs, development of long-lasting and curative therapies has been consistently attempted, with the aim of correcting the underlying molecular defect. In this review, we will specifically address the few combined cell and gene therapy strategies that made it to the clinics. Based on these studies, what can be envisioned for the future is a patient-oriented strategy, built on the specific features of the individual in need. Most likely, a combination of different strategies, approaches, and advanced therapies will be required to reach the finish line at the end of the long and winding road hampering the achievement of definitive treatments for genodermatoses.

Although they are usually not considered to be diabetes complications, musculoskeletal disorders (MSKDs) are common in individuals with type 1 or type 2 diabetes and can strongly interfere with daily diabetes care, especially in people using diabetes technologies. The authors of this retrospective study in a population of 140 patients with type 1 diabetes report the distribution of subtypes of MSKDs and speculate about the mechanisms involved. The authors emphasize the need for multidisciplinary care involving not only the diabetes care team but also orthopedic surgeons. This report should lead to large, prospective studies to increase knowledge about these under-studied complications.