Phase 3 Trial of Sotatercept for Treatment of Pulmonary Arterial Hypertension.

BACKGROUND: Pulmonary arterial hypertension is a progressive disease involving proliferative remodeling of the pulmonary vessels. Despite therapeutic advances, the disease-associated morbidity and mortality remain high. Sotatercept is a fusion protein that traps activins and growth differentiation factors involved in pulmonary arterial hypertension. METHODS: We conducted a multicenter, double-blind, phase 3 trial in which adults with pulmonary arterial hypertension (World Health Organization [WHO] functional class II or III) who were receiving stable background therapy were randomly assigned in a 1:1 ratio to receive subcutaneous sotatercept (starting dose, 0.3 mg per kilogram of body weight; target dose, 0.7 mg per kilogram) or placebo every 3 weeks. The primary end point was the change from baseline at week 24 in the 6-minute walk distance. Nine secondary end points, tested hierarchically in the following order, were multicomponent improvement, change in pulmonary vascular resistance, change in N-terminal pro-B-type natriuretic peptide level, improvement in WHO functional class, time to death or clinical worsening, French risk score, and changes in the Pulmonary Arterial Hypertension-Symptoms and Impact (PAH-SYMPACT) Physical Impacts, Cardiopulmonary Symptoms, and Cognitive/Emotional Impacts domain scores; all were assessed at week 24 except time to death or clinical worsening, which was assessed when the last patient completed the week 24 visit. RESULTS: A total of 163 patients were assigned to receive sotatercept and 160 to receive placebo. The median change from baseline at week 24 in the 6-minute walk distance was 34.4 m (95% confidence interval [CI], 33.0 to 35.5) in the sotatercept group and 1.0 m (95% CI, -0.3 to 3.5) in the placebo group. The Hodges-Lehmann estimate of the difference between the sotatercept and placebo groups in the change from baseline at week 24 in the 6-minute walk distance was 40.8 m (95% CI, 27.5 to 54.1; P<0.001). The first eight secondary end points were significantly improved with sotatercept as compared with placebo, whereas the PAH-SYMPACT Cognitive/Emotional Impacts domain score was not. Adverse events that occurred more frequently with sotatercept than with placebo included epistaxis, dizziness, telangiectasia, increased hemoglobin levels, thrombocytopenia, and increased blood pressure. CONCLUSIONS: In patients with pulmonary arterial hypertension who were receiving stable background therapy, sotatercept resulted in a greater improvement in exercise capacity (as assessed by the 6-minute walk test) than placebo. (Funded by Acceleron Pharma, a subsidiary of MSD; STELLAR ClinicalTrials.gov number, NCT04576988.).

Investigation of factors that may affect the foveal avascular zone: An optical coherence tomography angiography study.

SIGNIFICANCE: An understanding of factors that affect the foveal avascular zone (FAZ) in healthy eyes may aid in the early identification of patients at risk of retinal pathology, thereby allowing better management and preventive measures to be implemented. PURPOSE: The size and shape of the FAZ can change due to retinal diseases associated with oxidative stress, including diabetic retinopathy, glaucoma, and macular degeneration. This study aimed to assess the relationship, if any, between factors that may affect the superficial FAZ (i.e., vessel density, vessel perfusion, overweight/obesity) and possible links with macular pigment optical density in young, healthy participants. METHODS: One hundred thirty-nine participants aged 18 to 35 years were recruited to this cross-sectional study. The superficial FAZ area, foveal vascularity, and central macular thickness (CMT) were assessed using the Cirrus 5000. Health parameters, body mass index, trunk fat %, and macular pigment were analyzed to determine possible associations with the superficial FAZ. RESULTS: Mean FAZ area was 0.23 ± 0.08 mm2. Females had a significantly larger mean FAZ area than males (p=0.002). The FAZ area was positively correlated with body mass index (Pearson's r = 0.189, p=0.026). Significant correlates of the FAZ area in the multivariate model included vessel perfusion (central), CMT, and trunk fat %, collectively explaining 65.1% of the overall variability. CONCLUSIONS: Study findings suggest that reduced vessel perfusion, thinner CMT, and higher trunk fat % are plausible predictors of a larger FAZ area in healthy Caucasian adults. Low macular pigment optical density was, however, not associated with increased FAZ size in young healthy eyes. Noninvasive optical coherence tomography angiography testing, in association with these predictors, may aid in the early detection and monitoring of retinal diseases associated with oxidative stress.

Shifting incidence and survival of epithelial ovarian cancer (1995-2014): A SurvMark-2 study.

The aim of the study is to provide a comprehensive assessment of incidence and survival trends of epithelial ovarian cancer (EOC) by histological subtype across seven high income countries (Australia, Canada, Denmark, Ireland, New Zealand, Norway and the United Kingdom). Data on invasive EOC diagnosed in women aged 15 to 99 years during 1995 to 2014 were obtained from 20 cancer registries. Age standardized incidence rates and average annual percentage change were calculated by subtype for all ages and age groups (15-64 and 65-99 years). Net survival (NS) was estimated by subtype, age group and 5-year period using Pohar-Perme estimator. Our findings showed marked increase in serous carcinoma incidence was observed between 1995 and 2014 among women aged 65 to 99 years with average annual increase ranging between 2.2% and 5.8%. We documented a marked decrease in the incidence of adenocarcinoma "not otherwise specified" with estimates ranging between 4.4% and 7.4% in women aged 15 to 64 years and between 2.0% and 3.7% among the older age group. Improved survival, combining all EOC subtypes, was observed for all ages combined over the 20-year study period in all countries with 5-year NS absolute percent change ranging between 5.0 in Canada and 12.6 in Denmark. Several factors such as changes in guidelines and advancement in diagnostic tools may potentially influence the observed shift in histological subtypes and temporal trends. Progress in clinical management and treatment over the past decades potentially plays a role in the observed improvements in EOC survival.

The peritoneal cancer index as a predictor of complete cytoreduction at primary and interval cytoreductive surgery in advanced ovarian cancer.

OBJECTIVE: The peritoneal cancer index quantitatively assesses cancer distribution and tumor burden in the peritoneal cavity. The aim of this study is to evaluate the association between the peritoneal cancer index and completeness of surgical cytoreduction for ovarian cancer and to identify a cut-off above which complete cytoreduction is unlikely. METHODS: This is a single-center prospective cohort observational study. A total of 100 consecutive patients who underwent ovarian cancer surgery were included. Peritoneal cancer index scores prior to and after surgery were calculated, and a cut-off value for incomplete cytoreduction was identified using a receiver operator characteristic (ROC) curve. Surgical complexity, blood loss, length of surgery, and complications were analyzed and associations with the peritoneal cancer index score were evaluated. RESULTS: The overall median peritoneal cancer index score was 9.5 (range 0-36). The median age of the patients was 61 years (range 24-85). The most common stage was III (13% stage II, 53% stage III, 34% stage IV) and the most common histologic sub-type was high-grade serous (76% high-grade serous, 8% low-grade serous, 5% clear cell, 4% serous borderline, 2% endometrioid, 2% adult granulosa cell, 2% adenocarcinoma, 1% carcinosarcoma). Complete cytoreduction was achieved in 82% of patients, with a median score of 9 (range 0-30). The remaining 18% had a median score of 28.5 (range 0-36). The best predictor of incomplete cytoreduction was the peritoneal cancer index score, with an area under the curve (AUC) of 0.928 (95% CI 0.85 to 1.00). ROC curve analysis determined a peritoneal cancer index cut-off score of 20. Major complications occurred in 15% of patients with peritoneal cancer index scores >20 and in 2.5% of patients with scores ≤20, which was statistically significant (p=0.014). CONCLUSIONS: In our study we found that a peritoneal cancer index score of ≤20 was associated with a high likelihood of complete cytoreduction. Incorporating the peritoneal cancer index into routine surgical practice and research may impact treatment plans.

Biofilm-Mediated Fragmentation and Degradation of Microcrystalline Cellulose by Cellulomonas flavigena KU (ATCC 53703).

Cellulomonas flavigena KU (ATCC 53703) produces an extracellular matrix involved in the degradation of microcrystalline cellulose. This extracellular material is primarily composed of the gel-forming, ß-1,3-glucan known as curdlan and associated, cellulose-degrading enzymes. In this study, the effects of various forms of nutrient limitation on cellulose attachment, cellular aggregation, curdlan production, and biofilm formation were investigated throughout a 7-day incubation period by using phase-contrast microscopy. Compared to cultures grown in non-limiting media, nitrogen-limitation promoted early attachment of C. flavigena KU cells to the cellulose surface, and cellulose attachment was congruent with cellular aggregation and curdlan production. Over the course of the experiment, microcolonies of attached cells grew into curdlan-producing biofilms on the cellulose. By contrast, bacterial cells grown on cellulose in non-limiting media remained unattached and unaggregated throughout most of the incubation period. By 7 days of incubation, bacterial aggregation was ninefold greater in N-limited cultures compared to nutritionally complete cultures. In a similar way, phosphorus- and vitamin-limitation (i.e., yeast extract-limitation) also resulted in early cellulose attachment and biofilm formation. Furthermore, nutrient limitation promoted more rapid and efficient fragmentation and degradation of cellulose, with cellulose fragments in low-N media averaging half the size of those in high-N media after 7 days. Two modes of cellulose degradation are proposed for C. flavigena KU, a "planktonic mode" and a "biofilm mode". Similar observations have been reported for other curdlan-producing cellulomonads, and these differing cellulose degradation strategies may ultimately prove to reflect sequential stages of a multifaceted biofilm cycle important in the bioconversion of this abundant and renewable natural resource.

Exploring the link between cancer policies and cancer survival: a comparison of International Cancer Benchmarking Partnership countries.

Cancer policy differences might help to explain international variation in cancer survival, but empirical evidence is scarce. We reviewed cancer policies in 20 International Cancer Benchmarking Partnership jurisdictions in seven countries and did exploratory analyses linking an index of cancer policy consistency over time, with monitoring and implementation mechanisms, to survival from seven cancers in a subset of ten jurisdictions from 1995 to 2014. All ten jurisdictions had structures in place to oversee or deliver cancer control policies and had published at least one major cancer plan. Few cancer plans had explicit budgets for implementation or mandated external evaluation. Cancer policy consistency was positively correlated with improvements in survival over time for six of the seven cancer sites. Jurisdictions that scored the highest on policy consistency had large improvements in survival for most sites. Our analysis provides an important first step to systematically capture and evaluate what are inherently complex policy processes. The findings can help guide policy makers seeking approaches and frameworks to improve cancer services and, ultimately, cancer outcomes.

Neural correlates of multisensory enhancement in audiovisual narrative speech perception: A fMRI investigation.

This fMRI study investigated the effect of seeing articulatory movements of a speaker while listening to a naturalistic narrative stimulus. It had the goal to identify regions of the language network showing multisensory enhancement under synchronous audiovisual conditions. We expected this enhancement to emerge in regions known to underlie the integration of auditory and visual information such as the posterior superior temporal gyrus as well as parts of the broader language network, including the semantic system. To this end we presented 53 participants with a continuous narration of a story in auditory alone, visual alone, and both synchronous and asynchronous audiovisual speech conditions while recording brain activity using BOLD fMRI. We found multisensory enhancement in an extensive network of regions underlying multisensory integration and parts of the semantic network as well as extralinguistic regions not usually associated with multisensory integration, namely the primary visual cortex and the bilateral amygdala. Analysis also revealed involvement of thalamic brain regions along the visual and auditory pathways more commonly associated with early sensory processing. We conclude that under natural listening conditions, multisensory enhancement not only involves sites of multisensory integration but many regions of the wider semantic network and includes regions associated with extralinguistic sensory, perceptual and cognitive processing.

Diagnostic routes and time intervals for ovarian cancer in nine international jurisdictions; findings from the International Cancer Benchmarking Partnership (ICBP).

BACKGROUND: International Cancer Benchmarking Partnership Module 4 reports the first international comparison of ovarian cancer (OC) diagnosis routes and intervals (symptom onset to treatment start), which may inform previously reported variations in survival and stage. METHODS: Data were collated from 1110 newly diagnosed OC patients aged >40 surveyed between 2013 and 2015 across five countries (51-272 per jurisdiction), their primary-care physicians (PCPs) and cancer treatment specialists, supplement by treatment records or clinical databases. Diagnosis routes and time interval differences using quantile regression with reference to Denmark (largest survey response) were calculated. RESULTS: There were no significant jurisdictional differences in the proportion diagnosed with symptoms on the Goff Symptom Index (53%; P = 0.179) or National Institute for Health and Care Excellence NG12 guidelines (62%; P = 0.946). Though the main diagnosis route consistently involved primary-care presentation (63-86%; P = 0.068), onward urgent referral rates varied significantly (29-79%; P < 0.001). In most jurisdictions, diagnostic intervals were generally shorter and other intervals, in particular, treatment longer compared to Denmark. CONCLUSION: This study highlights key intervals in the diagnostic pathway where improvements could be made. It provides the opportunity to consider the systems and approaches across different jurisdictions that might allow for more timely ovarian cancer diagnosis and treatment.

An International Consensus on Actions to Improve Lung Cancer Survival: A Modified Delphi Method Among Clinical Experts in the International Cancer Benchmarking Partnership.

BACKGROUND: Research from the International Cancer Benchmarking Partnership (ICBP) demonstrates that international variation in lung cancer survival persists, particularly within early stage disease. There is a lack of international consensus on the critical contributing components to variation in lung cancer outcomes and the steps needed to optimise lung cancer services. These are needed to improve the quality of options for and equitable access to treatment, and ultimately improve survival. METHODS: Semi-structured interviews were conducted with 9 key informants from ICBP countries. An international clinical network representing 6 ICBP countries (Australia, Canada, Denmark, England, Ireland, New Zealand, Northern Ireland, Scotland & Wales) was established to share local clinical insights and examples of best practice. Using a modified Delphi consensus model, network members suggested and rated recommendations to optimise the management of lung cancer. Calls to Action were developed via Delphi voting as the most crucial recommendations, with Good Practice Points included to support their implementation. RESULTS: Five Calls to Action and thirteen Good Practice Points applicable to high income, comparable countries were developed and achieved 100% consensus. Calls to Action include (1) Implement cost-effective, clinically efficacious, and equitable lung cancer screening initiatives; (2) Ensure diagnosis of lung cancer within 30 days of referral; (3) Develop Thoracic Centres of Excellence; (4) Undertake an international audit of lung cancer care; and (5) Recognise improvements in lung cancer care and outcomes as a priority in cancer policy. CONCLUSION: The recommendations presented are the voice of an expert international lung cancer clinical network, and signpost key considerations for policymakers in countries within the ICBP but also in other comparable high-income countries. These define a roadmap to help align and focus efforts in improving outcomes and management of lung cancer patients globally.

Discovery of pyridyl urea sulfonamide inhibitors of NaV1.7.

NaV1.7 is an actively pursued, genetically validated, target for pain. Recently reported quinolinone sulfonamide inhibitors displayed promising selectivity profiles as well as efficacy in preclinical pain models; however, concerns about off-target liabilities associated with this series resulted in an effort to reduce the lipophilicity of these compounds. Successful prosecution of this strategy was challenging due to the opposing requirement for lipophilic inhibitors for NaV1.7 potency and in vivo clearance (CL). Deconstruction of the heterocyclic core of the quinolinone series and utilization of an intramolecular hydrogen bond to mimic the requisite pharmacophore enabled the introduction of polarity without adversely impacting CL. Ultimately, this strategy led to the identification of compound 29, which demonstrated favorable ADME and was efficacious in pre-clinical models of pain.

Revisiting the Pig IGHC Gene Locus in Different Breeds Uncovers Nine Distinct IGHG Genes.

IgG subclass diversification is common in placental mammals. It has been well documented in humans and mice that different IgG subclasses, with diversified functions, synergistically regulate humoral immunity. However, our knowledge on the genomic and functional diversification of IgG subclasses in the pig, a mammalian species with high agricultural and biomedical importance, is incomplete. Using bacterial artificial chromosome sequencing and newly assembled genomes generated by the PacBio sequencing approach, we characterized and mapped the IgH C region gene locus in three indigenous Chinese breeds (Erhualian, Xiang, and Luchuan) and compared them to that of Duroc. Our data revealed that IGHG genes in Chinese pigs differ from the Duroc, whereas the IGHM, IGHD, IGHA, and IGHE genes were all single copy and highly conserved in the pig breeds examined. Most striking were differences in numbers of IGHG genes: there are seven genes in Erhualian pigs, six in the Duroc, but only five in Xiang pigs. Phylogenetic analysis suggested that all reported porcine IGHG genes could be classified into nine subclasses: IGHG1, IGHG2a, IGHG2b, IGHG2c, IGHG3, IGHG4, IGHG5a, IGHG5b, and IGHG5c. Using sequence information, we developed a mouse mAb specific for IgG3. This study offers a starting point to investigate the structure-function relationship of IgG subclasses in pigs.

Patient outcomes following interval and delayed cytoreductive surgery in advanced ovarian cancer: protocol for a multicenter, international, cohort study (Global Gynaecological Oncology Surgical Outcomes Collaborative).

BACKGROUND: The Global Gynecological Oncology Surgical Outcomes Collaborative (GO SOAR) has developed a network of gynecological oncology surgeons, surgical departments, and other interested parties that have the long-term ability to collaborate on outcome studies. Presented is the protocol for the GO SOAR2 study. PRIMARY OBJECTIVES: To compare survival following interval and delayed cytoreductive surgery, between delayed cytoreductive surgery and no surgery (chemotherapy alone); and international variations in access to cytoreductive surgery for women with stage III-IV epithelial ovarian cancer. STUDY HYPOTHESES: There is no difference in survival following interval and delayed cytoreductive surgery; there is poorer survival with no surgery compared with delayed cytoreductive surgery; and there are international disparities in prevalent practice and access to cytoreductive surgery in women with stage III-IV epithelial ovarian cancer. TRIAL DESIGN: International, multicenter, mixed-methods cohort study. Participating centers, will review medical charts/electronic records of patients who had been consecutively diagnosed with stage III-IV ovarian cancer between January 1, 2006 and December 31, 2021. Qualitative interviews will be conducted to identify factors determining international variations in prevalent practice and access to cytoreductive surgery. MAJOR INCLUSION/EXCLUSION CRITERIA: Inclusion criteria include women with stage III-IV epithelial ovarian cancer, undergoing interval (after 3-4 cycles of chemotherapy) or delayed (≥5 cycles of chemotherapy) cytoreductive surgeries or no cytoreductive surgery (≥5 cycles of chemotherapy alone). PRIMARY ENDPOINTS: Overall survival (defined from date of diagnosis to date of death); progression-free survival (defined from date of diagnosis to date of first recurrence); facilitator/barriers to prevalent practice and access to cytoreductive surgery. SAMPLE SIZE: In order to determine whether there is a difference in survival following interval and delayed cytoreductive surgery and no surgery, data will be abstracted from 1000 patients. ESTIMATED DATES FOR COMPLETING ACCRUAL AND PRESENTING RESULTS: It is estimated that recruitment will be completed by 2023, and results published by 2024. TRIAL REGISTRATION: NCT05523804.

Considerations for multimodal prehabilitation in women with gynaecological cancers: a scoping review using realist principles.

BACKGROUND: There is increasing recognition that prehabilitation is important as a means of preparing patients physically and psychologically for cancer treatment. However, little is understood about the role and optimal nature of prehabilitation for gynaecological cancer patients, who usually face extensive and life-changing surgery in addition to other treatments that impact significantly on physiological and psychosexual wellbeing. REVIEW QUESTION: This scoping review was conducted to collate the research evidence on multimodal prehabilitation in gynaecological cancers and the related barriers and facilitators to engagement and delivery that should be considered when designing a prehabilitation intervention for this group of women. METHODS: Seven medical databases and four grey literature repositories were searched from database inception to September 2021. All articles, reporting on multimodal prehabilitation in gynaecological cancers were included in the final review, whether qualitative, quantitative or mixed-methods. Qualitative studies on unimodal interventions were also included, as these were thought to be more likely to include information about barriers and facilitators which could also be relevant to multimodal interventions. A realist framework of context, mechanism and outcome was used to assist interpretation of findings. RESULTS: In total, 24 studies were included in the final review. The studies included the following tumour groups: ovarian only (n = 12), endometrial only (n = 1), mixed ovarian, endometrial, vulvar (n = 5) and non-specific gynaecological tumours (n = 6). There was considerable variation across studies in terms of screening for prehabilitation, delivery of prehabilitation and outcome measures. Key mechanisms and contexts influencing engagement with prehabilitation can be summarised as: (1) The role of healthcare professionals and organisations (2) Patients' perceptions of acceptability (3) Factors influencing patient motivation (4) Prehabilitation as a priority (5) Access to prehabilitation. IMPLICATIONS FOR PRACTICE: A standardised and well evidenced prehabilitation programme for women with gynaecological cancer does not yet exist. Healthcare organisations and researchers should take into account the enablers and barriers to effective engagement by healthcare professionals and by patients, when designing and evaluating prehabilitation for gynaecological cancer patients.

R. L. Pritchard's classic mutual impedance contribution.

The Reflections series takes a look back on historical articles from The Journal of the Acoustical Society of America that have had a significant impact on the science and practice of acoustics.

Enantioselective Synthesis of (-)-10-Hydroxyacutuminine.

An enantioselective synthesis of (-)-10-hydroxyacutuminine is reported. Central to our strategy is a photochemical [2+2] cycloaddition that forges two of the quaternary stereocenters present in the acutumine alkaloids. A subsequent retro-aldol/Dieckmann sequence furnishes the spirocyclic cyclopentenone. Efforts to chlorinate the acutumine scaffold at C10 under heterolytic or radical deoxychlorination conditions led to the synthesis of an unexpected cyclopropane-containing pentacycle.

Population-based cancer staging for oesophageal, gastric, and pancreatic cancer 2012-2014: International Cancer Benchmarking Partnership SurvMark-2.

Cancer stage at diagnosis is important information for management and treatment of individual patients as well as in epidemiological studies to evaluate effectiveness of health care system in managing cancer patients. Population-based studies to examine international disparities on cancer survival by stage, however, has been challenging due to the lack of international standardization on recording stage information and variation in stage completeness across regions and countries. The International Cancer Benchmarking Partnership (ICBP) previously assessed the availability and comparability of staging information for colorectal, lung, female breast and ovarian cancers. Stage conversion algorithms were developed to aggregate and map all stage information into a single staging system to allow international comparison by stage at diagnosis. In this article, we developed stage conversion algorithms for three additional cancers, namely oesophageal, gastric and pancreatic cancers. We examined all stage information available, evaluated stage completeness, applied each stage conversion algorithm, and assessed the magnitude of misclassification using data from six Canadian cancer registries (Alberta, Manitoba, Newfoundland, Nova Scotia, Prince Edward Island and Saskatchewan). In addition, we discussed five recommendations for registries to improve international cancer survival comparison by stage: (a) improve collection and completeness of staging data; (b) promote a comparable definition for stage at diagnosis; (c) promote the use of a common stage classification system; (d) record versions of staging classifications and (e) use multiple data sources for valid staging data.

Extracellular vesicles impose quiescence on residual hematopoietic stem cells in the leukemic niche.

Progressive remodeling of the bone marrow microenvironment is recognized as an integral aspect of leukemogenesis. Expanding acute myeloid leukemia (AML) clones not only alter stroma composition, but also actively constrain hematopoiesis, representing a significant source of patient morbidity and mortality. Recent studies revealed the surprising resistance of long-term hematopoietic stem cells (LT-HSC) to elimination from the leukemic niche. Here, we examine the fate and function of residual LT-HSC in the BM of murine xenografts with emphasis on the role of AML-derived extracellular vesicles (EV). AML-EV rapidly enter HSC, and their trafficking elicits protein synthesis suppression and LT-HSC quiescence. Mechanistically, AML-EV transfer a panel of miRNA, including miR-1246, that target the mTOR subunit Raptor, causing ribosomal protein S6 hypo-phosphorylation, which in turn impairs protein synthesis in LT-HSC. While HSC functionally recover from quiescence upon transplantation to an AML-naive environment, they maintain relative gains in repopulation capacity. These phenotypic changes are accompanied by DNA double-strand breaks and evidence of a sustained DNA-damage response. In sum, AML-EV contribute to niche-dependent, reversible quiescence and elicit persisting DNA damage in LT-HSC.

Assessment of intramyocardial hemorrhage with dark-blood T2*-weighted cardiovascular magnetic resonance.

BACKGROUND: Intramyocardial hemorrhage (IMH) within myocardial infarction (MI) is associated with major adverse cardiovascular events. Bright-blood T2*-based cardiovascular magnetic resonance (CMR) has emerged as the reference standard for non-invasive IMH detection. Despite this, the dark-blood T2*-based CMR is becoming interchangeably used with bright-blood T2*-weighted CMR in both clinical and preclinical settings for IMH detection. To date however, the relative merits of dark-blood T2*-weighted with respect to bright-blood T2*-weighted CMR for IMH characterization has not been studied. We investigated the diagnostic capacity of dark-blood T2*-weighted CMR against bright-blood T2*-weighted CMR for IMH characterization in clinical and preclinical settings. MATERIALS AND METHODS: Hemorrhagic MI patients (n = 20) and canines (n = 11) were imaged in the acute and chronic phases at 1.5 and 3 T with dark- and bright-blood T2*-weighted CMR. Imaging characteristics (Relative signal-to-noise (SNR), Relative contrast-to-noise (CNR), IMH Extent) and diagnostic performance (sensitivity, specificity, accuracy, area-under-the-curve, and inter-observer variability) of dark-blood T2*-weighted CMR for IMH characterization were assessed relative to bright-blood T2*-weighted CMR. RESULTS: At both clinical and preclinical settings, compared to bright-blood T2*-weighted CMR, dark-blood T2*-weighted images had significantly lower SNR, CNR and reduced IMH extent (all p < 0.05). Dark-blood T2*-weighted CMR also demonstrated weaker sensitivity, specificity, accuracy, and inter-observer variability compared to bright-blood T2*-weighted CMR (all p < 0.05). These observations were consistent across infarct age and imaging field strengths. CONCLUSION: While IMH can be visible on dark-blood T2*-weighted CMR, the overall conspicuity of IMH is significantly reduced compared to that observed in bright-blood T2*-weighted images, across infarct age in clinical and preclinical settings at 1.5 and 3 T. Hence, bright-blood T2*-weighted CMR would be preferable for clinical use since dark-blood T2*-weighted CMR carries the potential to misclassify hemorrhagic MIs as non-hemorrhagic MIs.

Neurophysiological correlates of dual tasking in people with Parkinson's disease and freezing of gait.

Freezing of gait in people with Parkinson's disease (PwP) is associated with executive dysfunction and motor preparation deficits. We have recently shown that electrophysiological markers of motor preparation, rather than decision-making, differentiate PwP with freezing of gait (FOG +) and without (FOG -) while sitting. To examine the effect of locomotion on these results, we measured behavioural and electrophysiological responses in PwP with and without FOG during a target response time task while sitting (single-task) and stepping-in-place (dual-task). Behavioural and electroencephalographic data were acquired from 18 PwP (eight FOG +) and seven young controls performing the task while sitting and stepping-in-place. FOG + had slower response times while stepping compared with sitting. However, response times were significantly faster while stepping compared with sitting for controls. Electrophysiological responses showed no difference in decision-making potentials (centroparietal positivity) between groups or conditions but there were differences in neurophysiological markers of response inhibition (N2) and motor preparation (lateralized readiness potential, LRP) in FOG + while performing a dual-task. This suggests that the addition of a second complex motor task (stepping-in-place) impacts automatic allocation of resources in FOG +, resulting in delayed response times. The impact of locomotion on the generation of the N2 and LRP potentials, particularly in freezers, indirectly implies that these functions compete with locomotion for resources. In the setting of multiple complex tasks or cognitive impairment, severe motor dysfunction may result, leading to freezing of gait.

A comparative analysis: international variation in PET-CT service provision in oncology-an International Cancer Benchmarking Partnership study.

OBJECTIVE: To explore differences in position emission tomography-computed tomography (PET-CT) service provision internationally to further understand the impact variation may have upon cancer services. To identify areas of further exploration for researchers and policymakers to optimize PET-CT services and improve the quality of cancer services. DESIGN: Comparative analysis using data based on pre-defined PET-CT service metrics from PET-CT stakeholders across seven countries. This was further informed via document analysis of clinical indication guidance and expert consensus through round-table discussions of relevant PET-CT stakeholders. Descriptive comparative analyses were produced on use, capacity and indication guidance for PET-CT services between jurisdictions. SETTING: PET-CT services across 21 jurisdictions in seven countries (Australia, Denmark, Canada, Ireland, New Zealand, Norway and the UK). PARTICIPANTS: None. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): None. RESULTS: PET-CT service provision has grown over the period 2006-2017, but scale of increase in capacity and demand is variable. Clinical indication guidance varied across countries, particularly for small-cell lung cancer staging and the specific acknowledgement of gastric cancer within oesophagogastric cancers. There is limited and inconsistent data capture, coding, accessibility and availability of PET-CT activity across countries studied. CONCLUSIONS: Variation in PET-CT scanner quantity, acquisition over time and guidance upon use exists internationally. There is a lack of routinely captured and accessible PET-CT data across the International Cancer Benchmarking Partnership countries due to inconsistent data definitions, data linkage issues, uncertain coverage of data and lack of specific coding. This is a barrier in improving the quality of PET-CT services globally. There needs to be greater, richer data capture of diagnostic and staging tools to facilitate learning of best practice and optimize cancer services.