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1.
J Med Educ Curric Dev ; 11: 23821205241227328, 2024.
Article in English | MEDLINE | ID: mdl-38304279

ABSTRACT

Physicians must adapt their learning and expertise to the rapid evolution of healthcare. To train for the innovation-efficient demands of adaptive expertise, medical students need to acquire the skill of adaptive self-regulated learning, which includes accessing, interpreting, and synthesizing emerging basic and translational research to support patient care. In response, we developed the course Medical Student Grand Rounds (MSGR). It engages all pre-clerkship students at our institution with self-regulated learning from translational basic research literature. In this report, we describe MSGR's methodology and important outcomes. Students found, interpreted, critically assessed, and presented basic research literature about self-selected clinically relevant topics. In less than one semester and mentored by basic science researchers, they completed eight milestones: (a) search research literature databases; (b) choose a clinical topic using searching skills; (c) outline the topic's background; (d) outline a presentation based on the topic's mechanistic research literature; (e) attend translational research-oriented grand rounds by faculty; (f) learn to prepare oral presentations; (g) write an abstract; and (h) present at Grand Rounds Day, emphasizing their topic's research literature. Graded milestones and end-of-course self-assessments indicated students became proficient in interpreting research articles, preparing and delivering presentations, understanding links among basic and translational research and clinical applications, and pursuing self-regulated learning. Qualitative analysis of self-assessment surveys found most students thought they progressed toward the learning objectives: find scientific information about a research topic (56% positive responses), interpret and critically assess scientific information (64%), and prepare and deliver a scientific presentation (50%). Milestones improve time management and provide a scaffolded method for presenting focused research topics. MSGR equips students with critical thinking skills for lifelong, adaptive, self-regulated learning-a foundation for adaptive expertise. The master adaptive learner cycle of planning, learning, assessing, and adjusting is a conceptual framework for understanding students' MSGR learning experiences.

2.
Circulation ; 149(1): 7-23, 2024 01 02.
Article in English | MEDLINE | ID: mdl-37795617

ABSTRACT

BACKGROUND: We investigated the usefulness of invasive coronary function testing to diagnose the cause of angina in patients with no obstructive coronary arteries. METHODS: Outpatients referred for coronary computed tomography angiography in 3 hospitals in the United Kingdom were prospectively screened. After coronary computed tomography angiography, patients with unobstructed coronary arteries, and who consented, underwent invasive endotyping. The diagnostic assessments included coronary angiography, fractional flow reserve (patient excluded if ≤0.80), and, for those without obstructive coronary artery disease, coronary flow reserve (abnormal <2.0), index of microvascular resistance (abnormal ≥25), and intracoronary infusion of acetylcholine (0.182, 1.82, and 18.2 µg/mL; 2 mL/min for 2 minutes) to assess for microvascular and coronary spasm. Participants were randomly assigned to disclosure of the results of the coronary function tests to the invasive cardiologist (intervention group) or nondisclosure (control group, blinded). In the control group, a diagnosis of vasomotor angina was based on medical history, noninvasive tests, and coronary angiography. The primary outcome was the between-group difference in the reclassification rate of the initial diagnosis on the basis of coronary computed tomography angiography versus the final diagnosis after invasive endotyping. The Seattle Angina Questionnaire summary score and Treatment Satisfaction Questionnaire for Medication were secondary outcomes. RESULTS: Of 322 eligible patients, 250 (77.6%) underwent invasive endotyping; 19 (7.6%) had obstructive coronary disease, 127 (55.0%) had microvascular angina, 27 (11.7%) had vasospastic angina, 17 (7.4%) had both, and 60 (26.0%) had no abnormality. A total of 231 patients (mean age, 55.7 years; 64.5% women) were randomly assigned and followed up (median duration, 19.9 [12.6-26.9] months). The clinician diagnosed vasomotor angina in 51 (44.3%) patients in the intervention group and in 55 (47.4%) patients in the control group. After randomization, patients in the intervention group were 4-fold (odds ratio, 4.05 [95% CI, 2.32-7.24]; P<0.001) more likely to be diagnosed with a coronary vasomotor disorder; the frequency of this diagnosis increased to 76.5%. The frequency of normal coronary function (ie, no vasomotor disorder) was not different between the groups before randomization (51.3% versus 50.9%) but was reduced in the intervention group after randomization (23.5% versus 50.9%, P<0.001). At 6 and 12 months, the Seattle Angina Questionnaire summary score in the intervention versus control groups was 59.2±24.2 (2.3±16.2 change from baseline) versus 60.4±23.9 (4.6±16.4 change) and 63.7±23.5 (4.7±14.7 change) versus 66.0±19.3 (7.9±17.1 change), respectively, and not different between groups (global P=0.36). Compared with the control group, global treatment satisfaction was higher in the intervention group at 12 months (69.9±22.8 versus 61.7±26.9, P=0.013). CONCLUSIONS: For patients with angina and no obstructive coronary arteries, a diagnosis informed by invasive functional assessment had no effect on long-term angina burden, whereas treatment satisfaction improved. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03477890.


Subject(s)
Coronary Artery Disease , Fractional Flow Reserve, Myocardial , Microvascular Angina , Humans , Female , Middle Aged , Male , Coronary Artery Disease/diagnostic imaging , Coronary Angiography , United Kingdom
3.
Cereb Circ Cogn Behav ; 5: 100187, 2023.
Article in English | MEDLINE | ID: mdl-37811523

ABSTRACT

Cerebral small vessel disease (SVD) is a major cause of cognitive impairment in older people. As secondary endpoints in a phase-2 randomised clinical trial, we tested the effects of single administration of a widely-used PDE5 inhibitor, tadalafil, on cognitive performance in older people with SVD. In a double-blinded, placebo-controlled, cross-over trial, participants received tadalafil (20 mg) and placebo on two visits ≥ 7 days apart (randomised to order of treatment). The Montreal Cognitive Assessment (MOCA) was administered at baseline, alongside a measure to estimate optimal intellectual ability (Test of Premorbid Function). Then, before and after treatment, a battery of neuropsychological tests was administered, assessing aspects of attention, information processing speed, working memory and executive function. Sixty-five participants were recruited and 55 completed the protocol (N = 55, age: 66.8 (8.6) years, range 52-87; 15/40 female/male). Median MOCA score was 26 (IQR: 23, 27], range 15-30). No significant treatment effects were seen in any of the neuropsychological tests. There was a trend towards improved performance on Digit Span Forward (treatment effect 0.37, C.I. 0.01, 0.72; P = 0.0521). We did not identify significant treatment effects of single-administration tadalafil on neuropsychological performance in older people with SVD. The trend observed on Digit Span Forward may help to inform future studies. Clinical trial registration: http://www.clinicaltrials.gov. Unique identifier: NCT00123456, https://eudract.ema.europa.eu. Unique identifier: 2015-001,235-20NCT00123456.

4.
Br J Cancer ; 129(9): 1490-1499, 2023 10.
Article in English | MEDLINE | ID: mdl-37684354

ABSTRACT

BACKGROUND: Axitinib is an oral vascular endothelial growth factor receptor inhibitor with anti-tumour activity in renal, thyroid, and pancreatic cancer. METHODS: Axi-STS was a pathologically-stratified, non-randomised, open-label, multi-centre, phase II trial of continuous axitinib treatment in patients ≥16 years, performance status ≤2, with pathologically-confirmed advanced/metastatic soft tissue sarcoma (STS). Patients were recruited within four tumour strata, each analysed separately: angiosarcoma, leiomyosarcoma, synovial sarcoma, or other eligible STSs. The primary outcome was progression-free survival at 12 weeks (PFS12). A Simon's two-stage design with activity defined as PFS12 rate of 40% determined a sample size of 33 patients per strata. RESULTS: Between 31-August-2010 and 29-January-2016, 145 patients were recruited: 38 angiosarcoma, 37 leiomyosarcoma, 36 synovial sarcoma, and 34 other subtypes. PFS12 rate for each stratum analysed was 42% (95% lower confidence interval (LCI); 29), 45% (95% LCI; 32), 57% (95% LCI; 42), and 33% (95% LCI; 21), respectively. There were 74 serious adverse events including two treatment-related deaths of pulmonary haemorrhage and gastrointestinal bleeding. Fatigue and hypertension were the most common grade 3 adverse events. CONCLUSIONS: Axitinib showed clinical activity in all STS strata investigated. The adverse event profile was acceptable, supporting further investigation in phase III trials. CLINICAL TRIAL REGISTRATION: ISRCTN 60791336.


Subject(s)
Hemangiosarcoma , Leiomyosarcoma , Sarcoma, Synovial , Sarcoma , Soft Tissue Neoplasms , Humans , Axitinib/adverse effects , Leiomyosarcoma/drug therapy , Sarcoma, Synovial/chemically induced , Sarcoma, Synovial/drug therapy , Hemangiosarcoma/chemically induced , Hemangiosarcoma/drug therapy , Vascular Endothelial Growth Factor A , Sarcoma/drug therapy , Soft Tissue Neoplasms/drug therapy , Soft Tissue Neoplasms/pathology , Angiogenesis Inhibitors/therapeutic use , Treatment Outcome
5.
Int J Spine Surg ; 17(4): 482-483, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37607778
6.
Int J Spine Surg ; 17(S1): S3-S10, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37364938

ABSTRACT

The pace of US Food and Drug Administration-approved medical devices that incorporate artificial intelligence (AI) or machine learning as part of the device is accelerating. As of September 2021, 350 such devices have been approved for commercial sale in the United States. As much as AI has become ubiquitous in our lives-keeping our cars between the lines on the highway, converting speech to text on the fly, recommending movies, books, or restaurants, and so much more, AI also appears destined to become a routine aspect in daily spine surgery. Neural network types of AI programs have achieved extraordinary pattern recognition and predictive abilities-far surpassing human capabilities-and thus appears well suited to back pain and spine surgery diagnostic and treatment pattern recognition and prediction tasks. These AI programs are also data hungry. As luck would have it, surgery generates an estimated 80 MB per patient per day collected in a variety of datasets. When aggregated, this represents a 200+ billion patient record data ocean of diagnostic and treatment patterns. Such Big Data, when combined with a new generation of convolutional neural network (CNN) AI, set the stage for a cognitive revolution in spine surgery. However, there are important issues and concerns. Spine surgery is a mission-critical task. Because AI programs lack explainability and are absolutely reliant on correlative, not causative, data relationships, the emerging role of AI and Big Data in spine surgery will likely come first in productivity tools and later in narrowly defined spine surgery tasks. The purpose of this article is to review the emergence of AI in spine surgery applications and examine spine surgery heuristics and "expert" decision models within the context of AI and Big Data.

7.
Ann Glob Health ; 89(1): 32, 2023.
Article in English | MEDLINE | ID: mdl-37252336

ABSTRACT

Background: Place-based international electives that build global health competencies have existed for decades. However, these electives require travel and are infeasible for many trainees around the world, particularly those with insufficient financial resources, logistical complexities, or visa limitations. The emergence of virtual approaches to global health electives, catalyzed by the travel pause related to the COVID-19 pandemic, necessitates the exploration of learner impacts, participant diversity, and curricular frameworks. Child Family Health International (CFHI), a non-profit global health education organization that partners with universities to expand immersive educational offerings, launched a virtual global health elective in 2021. The elective drew on faculty from Bolivia, Ecuador, Ghana, Mexico, the Philippines, Uganda, and the United States. Objective: This study aimed to describe a newly developed virtual global health elective curriculum and evaluate the demographics of and impacts on trainee participants. Methods: Eighty-two trainees who were enrolled in the virtual global health elective from January to May 2021 completed both 1) pre- and post-elective self-assessments of domains of competency mapped to the elective curriculum and 2) free text responses to standardized questions. Data were analyzed through descriptive statistical analysis, paired t-testing, and qualitative thematic analysis. Findings: The virtual global health elective had 40% of its participants hail from countries other than the United States. Self-reported competency in global health broadly, planetary health, low resource clinical reasoning, and overall composite competency significantly increased. Qualitative analysis revealed learner development in health systems, social determinants of health, critical thinking, planetary health, cultural humility, and professional practice. Conclusion: Virtual global health electives effectively develop key competencies in global health. This virtual elective had a 40-fold increase in the proportion of trainees from outside the United States, compared to pre-pandemic place-based electives. The virtual platform facilitates accessibility for learners from a variety of health professions and a wide range of geographic and socioeconomic environments. Further research is needed to confirm and expand on self-reported data, and to pursue approaches to greater diversity, equity, and inclusion in virtual frameworks.


Subject(s)
COVID-19 , Pandemics , Child , United States , Humans , Global Health , COVID-19/epidemiology , Data Collection , Curriculum , Catalysis
9.
J Plast Reconstr Aesthet Surg ; 87: 479-490, 2023 12.
Article in English | MEDLINE | ID: mdl-36890078

ABSTRACT

BACKGROUND: The COVID pandemic brought the need for more realistic remote consultations into focus. 2D Telemedicine solutions fail to replicate the fluency or authenticity of in-person consultations. This research reports on an international collaboration on the participatory development and first validated clinical use of a novel, real-time 360-degree 3D Telemedicine system worldwide. The development of the system - leveraging Microsoft's Holoportation™ communication technology - commenced at the Canniesburn Plastic Surgery Unit, Glasgow, in March 2020. METHODS: The research followed the VR CORE guidelines on the development of digital health trials, placing patients at the heart of the development process. This consisted of three separate studies - a clinician feedback study (23 clinicians, Nov-Dec 2020), a patient feedback study (26 patients, Jul-Oct 2021), and a cohort study focusing on safety and reliability (40 patients, Oct 2021-Mar 2022). "Lose, Keep, and Change" feedback prompts were used to engage patients in the development process and guide incremental improvements. RESULTS: Participatory testing demonstrated improved patient metrics with 3D in comparison to 2D Telemedicine, including validated measures of satisfaction (p<0.0001), realism or 'presence' (Single Item Presence scale, p<0.0001), and quality (Telehealth Usability Questionnaire, p = 0.0002). The safety and clinical concordance (95%) of 3D Telemedicine with a face-to-face consultation were equivalent or exceeded estimates for 2D Telemedicine. CONCLUSIONS: One of the ultimate goals of telemedicine is for the quality of remote consultations to get closer to the experience of face-to-face consultations. These data provide the first evidence that Holoportation™ communication technology brings 3D Telemedicine closer to this goal than a 2D equivalent.


Subject(s)
COVID-19 , Remote Consultation , Telemedicine , Humans , Cohort Studies , Reproducibility of Results , COVID-19/epidemiology
10.
Circulation ; 147(5): 364-374, 2023 01 31.
Article in English | MEDLINE | ID: mdl-36705028

ABSTRACT

BACKGROUND: Acute myocardial injury in hospitalized patients with coronavirus disease 2019 (COVID-19) has a poor prognosis. Its associations and pathogenesis are unclear. Our aim was to assess the presence, nature, and extent of myocardial damage in hospitalized patients with troponin elevation. METHODS: Across 25 hospitals in the United Kingdom, 342 patients with COVID-19 and an elevated troponin level (COVID+/troponin+) were enrolled between June 2020 and March 2021 and had a magnetic resonance imaging scan within 28 days of discharge. Two prospective control groups were recruited, comprising 64 patients with COVID-19 and normal troponin levels (COVID+/troponin-) and 113 patients without COVID-19 or elevated troponin level matched by age and cardiovascular comorbidities (COVID-/comorbidity+). Regression modeling was performed to identify predictors of major adverse cardiovascular events at 12 months. RESULTS: Of the 519 included patients, 356 (69%) were men, with a median (interquartile range) age of 61.0 years (53.8, 68.8). The frequency of any heart abnormality, defined as left or right ventricular impairment, scar, or pericardial disease, was 2-fold greater in cases (61% [207/342]) compared with controls (36% [COVID+/troponin-] versus 31% [COVID-/comorbidity+]; P<0.001 for both). More cases than controls had ventricular impairment (17.2% versus 3.1% and 7.1%) or scar (42% versus 7% and 23%; P<0.001 for both). The myocardial injury pattern was different, with cases more likely than controls to have infarction (13% versus 2% and 7%; P<0.01) or microinfarction (9% versus 0% and 1%; P<0.001), but there was no difference in nonischemic scar (13% versus 5% and 14%; P=0.10). Using the Lake Louise magnetic resonance imaging criteria, the prevalence of probable recent myocarditis was 6.7% (23/342) in cases compared with 1.7% (2/113) in controls without COVID-19 (P=0.045). During follow-up, 4 patients died and 34 experienced a subsequent major adverse cardiovascular event (10.2%), which was similar to controls (6.1%; P=0.70). Myocardial scar, but not previous COVID-19 infection or troponin, was an independent predictor of major adverse cardiovascular events (odds ratio, 2.25 [95% CI, 1.12-4.57]; P=0.02). CONCLUSIONS: Compared with contemporary controls, patients with COVID-19 and elevated cardiac troponin level have more ventricular impairment and myocardial scar in early convalescence. However, the proportion with myocarditis was low and scar pathogenesis was diverse, including a newly described pattern of microinfarction. REGISTRATION: URL: https://www.isrctn.com; Unique identifier: 58667920.


Subject(s)
COVID-19 , Heart Injuries , Myocarditis , Female , Humans , Male , Middle Aged , Cicatrix , COVID-19/complications , COVID-19/epidemiology , Hospitalization , Prospective Studies , Risk Factors , Troponin , Aged
11.
Lancet ; 400(10361): 1417-1425, 2022 10 22.
Article in English | MEDLINE | ID: mdl-36240838

ABSTRACT

BACKGROUND: Studies have suggested that evening dosing with antihypertensive therapy might have better outcomes than morning dosing. The Treatment in Morning versus Evening (TIME) study aimed to investigate whether evening dosing of usual antihypertensive medication improves major cardiovascular outcomes compared with morning dosing in patients with hypertension. METHODS: The TIME study is a prospective, pragmatic, decentralised, parallel-group study in the UK, that recruited adults (aged ≥18 years) with hypertension and taking at least one antihypertensive medication. Eligible participants were randomly assigned (1:1), without restriction, stratification, or minimisation, to take all of their usual antihypertensive medications in either the morning (0600-1000 h) or in the evening (2000-0000 h). Participants were followed up for the composite primary endpoint of vascular death or hospitalisation for non-fatal myocardial infarction or non-fatal stroke. Endpoints were identified by participant report or record linkage to National Health Service datasets and were adjudicated by a committee masked to treatment allocation. The primary endpoint was assessed as the time to first occurrence of an event in the intention-to-treat population (ie, all participants randomly assigned to a treatment group). Safety was assessed in all participants who submitted at least one follow-up questionnaire. The study is registered with EudraCT (2011-001968-21) and ISRCTN (18157641), and is now complete. FINDINGS: Between Dec 17, 2011, and June 5, 2018, 24 610 individuals were screened and 21 104 were randomly assigned to evening (n=10 503) or morning (n=10 601) dosing groups. Mean age at study entry was 65·1 years (SD 9·3); 12 136 (57·5%) participants were men; 8968 (42·5%) were women; 19 101 (90·5%) were White; 98 (0·5%) were Black, African, Caribbean, or Black British (ethnicity was not reported by 1637 [7·8%] participants); and 2725 (13·0%) had a previous cardiovascular disease. By the end of study follow-up (March 31, 2021), median follow-up was 5·2 years (IQR 4·9-5·7), and 529 (5·0%) of 10 503 participants assigned to evening treatment and 318 (3·0%) of 10 601 assigned to morning treatment had withdrawn from all follow-up. A primary endpoint event occurred in 362 (3·4%) participants assigned to evening treatment (0·69 events [95% CI 0·62-0·76] per 100 patient-years) and 390 (3·7%) assigned to morning treatment (0·72 events [95% CI 0·65-0·79] per 100 patient-years; unadjusted hazard ratio 0·95 [95% CI 0·83-1·10]; p=0·53). No safety concerns were identified. INTERPRETATION: Evening dosing of usual antihypertensive medication was not different from morning dosing in terms of major cardiovascular outcomes. Patients can be advised that they can take their regular antihypertensive medications at a convenient time that minimises any undesirable effects. FUNDING: British Heart Foundation.


Subject(s)
Hypertension , Myocardial Infarction , Adult , Male , Humans , Female , Adolescent , Aged , Antihypertensive Agents/therapeutic use , Prospective Studies , State Medicine , Time and Motion Studies , Treatment Outcome , Hypertension/chemically induced , Myocardial Infarction/drug therapy , United Kingdom/epidemiology
12.
Cells ; 11(16)2022 08 17.
Article in English | MEDLINE | ID: mdl-36010633

ABSTRACT

Diet is a critical environmental factor affecting breast cancer risk, and recent evidence shows that dietary exposures during early development can affect lifetime mammary cancer susceptibility. To elucidate the underlying mechanisms, we used our established crossover feeding mouse model, where exposure to a high-fat and high-sugar (HFHS) diet during defined developmental windows determines mammary tumor incidence and latency in carcinogen-treated mice. Mammary tumor incidence is significantly increased in mice receiving a HFHS post-weaning diet (high-tumor mice, HT) compared to those receiving a HFHS diet during gestation (low-tumor mice, LT). The current study revealed that the mammary stem cell (MaSC) population was significantly increased in mammary glands from HT compared to LT mice. Igf1 expression was increased in mammary stromal cells from HT mice, where it promoted MaSC self-renewal. The increased Igf1 expression was induced by DNA hypomethylation of the Igf1 Pr1 promoter, mediated by a decrease in Dnmt3b levels. Mammary tissues from HT mice also had reduced levels of Igfbp5, leading to increased bioavailability of tissue Igf1. This study provides novel insights into how early dietary exposures program mammary cancer risk, demonstrating that effective dietary intervention can reduce mammary cancer incidence.


Subject(s)
Dietary Exposure , Mammary Neoplasms, Animal , Animals , Carcinogens , Diet , Mammary Neoplasms, Animal/metabolism , Mice , Stem Cells/metabolism
13.
ESC Heart Fail ; 9(4): 2207-2214, 2022 08.
Article in English | MEDLINE | ID: mdl-35619238

ABSTRACT

AIMS: Synchronized diaphragmatic stimulation (SDS) modulates intrathoracic and intra-abdominal pressures with favourable effects on cardiac function for patients with a reduced left ventricular ejection fraction (LVEF) and heart failure (HFrEF). VisONE-HF is a first-in-patient, observational study assessing the feasibility and 1 year effects of a novel, minimally invasive SDS device. METHODS AND RESULTS: The SDS system comprises a pulse generator and two laparoscopically delivered, bipolar, active-fixation leads on the inferior diaphragmatic surface. Fifteen symptomatic men with HFrEF and ischaemic heart disease receiving guideline-recommended therapy were enrolled (age 60 [56, 67] years, New York Heart Association class II [53%] /III [47%], LVEF 27 [23, 33] %, QRSd 117 [100, 125] ms, & N terminal pro brain natriuretic peptide [NT-proBNP] 1779 [911, 2,072] pg/mL). Implant success was 100%. Patients were evaluated at 3, 6, and 12 months for device-related or lead-related complications, quality of life (SF-36 QOL), 6 min hall walk distance (6MHWd), and by echocardiography. No implant procedure or SDS-related adverse event occurred, and patients were unaware of diaphragmatic stimulation. By 12 months, left ventricular end-systolic volume decreased (136 [123, 170] mL to 98 [89, 106] mL; P = 0.05), 6MHWd increased (315 [300, 330] m to 340 [315, 368] m; P = 0.004), and SF-36 QOL improved (physical scale 0 [0, 0] to 25 [0, 50], P = 0.006; emotional scale 0 [0, 33] to 33 [33, 67], P = 0.001). Although neither reached statistical significance, LVEF decreased (28 [23, 40]% vs. 34 [29, 38]%; P = ns) and NT-proBNP was lower (1784 [920, 2540] pg/mL vs. 1492 [879, 2028] pg/mL; P = ns). CONCLUSIONS: These data demonstrate the feasibility of laparoscopic implantation and delivery of SDS without raising safety concerns. These encouraging findings should be investigated further in adequately powered randomized trials.


Subject(s)
Heart Failure , Myocardial Ischemia , Humans , Male , Middle Aged , Myocardial Ischemia/complications , Quality of Life , Stroke Volume , Ventricular Function, Left
14.
Stem Cells ; 40(3): 273-289, 2022 03 31.
Article in English | MEDLINE | ID: mdl-35356986

ABSTRACT

Insulin-like growth factor I (IGF-1) has been implicated in breast cancer due to its mitogenic and anti-apoptotic effects. Despite substantial research on the role of IGF-1 in tumor progression, the relationship of IGF-1 to tissue stem cells, particularly in mammary tissue, and the resulting tumor susceptibility has not been elucidated. Previous studies with the BK5.IGF-1 transgenic (Tg) mouse model reveals that IGF-1 does not act as a classical, post-carcinogen tumor promoter in the mammary gland. Pre-pubertal Tg mammary glands display increased numbers and enlarged sizes of terminal end buds, a niche for mammary stem cells (MaSCs). Here we show that MaSCs from both wild-type (WT) and Tg mice expressed IGF-1R and that overexpression of Tg IGF-1 increased numbers of MaSCs by undergoing symmetric division, resulting in an expansion of the MaSC and luminal progenitor (LP) compartments in pre-pubertal female mice. This expansion was maintained post-pubertally and validated by mammosphere assays in vitro and transplantation assays in vivo. The addition of recombinant IGF-1 promoted, and IGF-1R downstream inhibitors decreased mammosphere formation. Single-cell transcriptomic profiles generated from 2 related platforms reveal that IGF-1 stimulated quiescent MaSCs to enter the cell cycle and increased their expression of genes involved in proliferation, plasticity, tumorigenesis, invasion, and metastasis. This study identifies a novel, pro-tumorigenic mechanism, where IGF-1 increases the number of transformation-susceptible carcinogen targets during the early stages of mammary tissue development, and "primes" their gene expression profiles for transformation.


Subject(s)
Insulin-Like Growth Factor I , Mammary Glands, Animal , Animals , Cell Proliferation , Female , Humans , Insulin-Like Growth Factor I/metabolism , Mice , Mice, Transgenic , Stem Cells/metabolism
15.
Alzheimers Dement ; 18(12): 2393-2402, 2022 12.
Article in English | MEDLINE | ID: mdl-35135037

ABSTRACT

INTRODUCTION: There are few randomized clinical trials in vascular cognitive impairment (VCI). This trial tested the hypothesis that the PDE5 inhibitor tadalafil, a widely used vasodilator, increases cerebral blood flow (CBF) in older people with symptomatic small vessel disease, the main cause of VCI. METHODS: In a double-blind, placebo-controlled, cross-over trial, participants received tadalafil (20 mg) and placebo on two visits ≥7 days apart (randomized to order of treatment). The primary endpoint, change in subcortical CBF, was measured by arterial spin labelling. RESULTS: Tadalafil increased CBF non-significantly in all subcortical areas (N = 55, age: 66.8 (8.6) years) with greatest treatment effect within white matter hyperintensities (+9.8%, P = .0960). There were incidental treatment effects on systolic and diastolic blood pressure (-7.8, -4.9 mmHg; P < .001). No serious adverse events were observed. DISCUSSION: This trial did not identify a significant treatment effect of single-administration tadalafil on subcortical CBF. To detect treatment effects may require different dosing regimens.


Subject(s)
Cognitive Dysfunction , Humans , Aged , Tadalafil/therapeutic use , Cognitive Dysfunction/drug therapy , Double-Blind Method
16.
Eur J Prev Cardiol ; 28(16): 1795-1806, 2022 Jan 11.
Article in English | MEDLINE | ID: mdl-35022686

ABSTRACT

BACKGROUND: In contrast with the setting of acute myocardial infarction, there are limited data regarding the impact of diabetes mellitus on clinical outcomes in contemporary cohorts of patients with chronic coronary syndromes. We aimed to investigate the prevalence and prognostic impact of diabetes according to geographical regions and ethnicity. METHODS AND RESULTS: CLARIFY is an observational registry of patients with chronic coronary syndromes, enrolled across 45 countries in Europe, Asia, America, Middle East, Australia, and Africa in 2009-2010, and followed up yearly for 5 years. Chronic coronary syndromes were defined by ≥1 of the following criteria: prior myocardial infarction, evidence of coronary stenosis >50%, proven symptomatic myocardial ischaemia, or prior revascularization procedure.Among 32 694 patients, 9502 (29%) had diabetes, with a regional prevalence ranging from below 20% in Northern Europe to ∼60% in the Gulf countries. In a multivariable-adjusted Cox proportional hazards model, diabetes was associated with increased risks for the primary outcome (cardiovascular death, myocardial infarction, or stroke) with an adjusted hazard ratio of 1.28 (95% confidence interval 1.18, 1.39) and for all secondary outcomes (all-cause and cardiovascular mortality, myocardial infarction, stroke, heart failure, and coronary revascularization). Differences on outcomes according to geography and ethnicity were modest. CONCLUSION: In patients with chronic coronary syndromes, diabetes is independently associated with mortality and cardiovascular events, including heart failure, which is not accounted by demographics, prior medical history, left ventricular ejection fraction, or use of secondary prevention medication. This is observed across multiple geographic regions and ethnicities, despite marked disparities in the prevalence of diabetes. CLINICALTRIALS IDENTIFIER: ISRCTN43070564.


Subject(s)
Coronary Artery Disease , Diabetes Mellitus , Coronary Artery Disease/epidemiology , Diabetes Mellitus/diagnosis , Diabetes Mellitus/epidemiology , Ethnicity , Humans , Prevalence , Risk Factors , Stroke Volume , Syndrome , Treatment Outcome , Ventricular Function, Left
17.
Acad Med ; 97(5): 684-688, 2022 05 01.
Article in English | MEDLINE | ID: mdl-34789666

ABSTRACT

PROBLEM: Understanding and communicating medical advances driven by basic research, and acquiring foundational skills in critically appraising and communicating translational basic research literature that affects patient care, are challenging for medical students to develop. APPROACH: The authors developed a mandatory course from 2012 to 2018 at Texas A&M University College of Medicine to address this problem. Medical Student Grand Rounds (MSGR) trains first-year students to find, critically assess, and present primary research literature about self-selected medically relevant topics. With basic science faculty mentoring, students completed milestones culminating in oral presentations. Students learned to search literature databases and then choose a clinical subject using these skills. They outlined the clinical subject area background and a mechanistic research topic into a clinical problem based on deeper evaluation of primary research literature. "Mechanistic" was defined in this context as providing experimental evidence that explained the "how" and "why" underlying clinical manifestations of a disease. Students received evaluations and feedback from mentors about discerning the quality of information and synthesizing information on their topics. Finally, students prepared and gave oral presentations, emphasizing the primary literature on their topics. OUTCOMES: In the early stages of the course development, students had difficulty critically assessing and evaluating research literature. Mentored training by research-oriented faculty, however, dramatically improved student perceptions of the MSGR experience. Mentoring helped students develop skills to synthesize ideas from basic research literature. According to grades and self-evaluations, students increased proficiency in finding and interpreting research articles, preparing and delivering presentations, and understanding links among basic and translational research and clinical applications. NEXT STEPS: The authors plan to survey fourth-year students who have completed MSGR about their perceptions of the course in the context of clinical experiences in medical school to guide future refinements.


Subject(s)
Education, Medical, Undergraduate , Students, Medical , Humans , Mentors , Schools, Medical , Translational Research, Biomedical
18.
Kidney Int ; 99(6): 1478-1486, 2021 06.
Article in English | MEDLINE | ID: mdl-34023029

ABSTRACT

Cardiovascular disease is the leading cause of death for patients receiving hemodialysis. Since exercise mitigates many risk factors which drive cardiovascular disease for these patients, we assessed effects of a program of intra-dialytic cycling on left ventricular mass and other prognostically relevant measures of cardiovascular disease as evaluated by cardiac MRI (the CYCLE-HD trial). This was a prospective, open-label, single-blinded cluster-randomized controlled trial powered to detect a 15g difference in left ventricular mass measured between patients undergoing a six-month program of intra-dialytic cycling (exercise group) and patients continuing usual care (control group). Pre-specified secondary outcomes included measures of myocardial fibrosis, aortic stiffness, physical functioning, quality of life and ventricular arrhythmias. Outcomes were analyzed as intention-to-treat according to a pre-specified statistical analysis plan. Initially, 130 individuals were recruited and completed baseline assessments (65 each group). Ultimately, 101 patients completed the trial protocol (50 control group and 51 exercise group). The six-month program of intra-dialytic cycling resulted in a significant reduction in left ventricular mass between groups (-11.1g; 95% confidence interval -15.79, -6.43), which remained significant on sensitivity analysis (missing data imputed) (-9.92g; 14.68, -5.16). There were significant reductions in both native T1 mapping and aortic pulse wave velocity between groups favoring the intervention. There was no increase in either ventricular ectopic beats or complex ventricular arrhythmias as a result of exercise with no significant effect on physical function or quality of life. Thus, a six-month program of intradialytic cycling reduces left ventricular mass and is safe, deliverable and well tolerated.


Subject(s)
Pulse Wave Analysis , Quality of Life , Exercise Therapy , Humans , Prospective Studies , Renal Dialysis/adverse effects
19.
Int J Cardiovasc Imaging ; 37(4): 1405-1414, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33258084

ABSTRACT

Patients with end-stage kidney disease (ESKD) are often sedentary and decreased functional capacity associates with mortality. The relationship between cardiovascular disease (CVD) and physical function has not been fully explored. Understanding the relationships between prognostically relevant measures of CVD and physical function may offer insight into how exercise interventions might target specific elements of CVD. 130 patients on haemodialysis (mean age 57 ± 15 years, 73% male, dialysis vintage 1.3 years (0.5, 3.4), recruited to the CYCLE-HD trial (ISRCTN11299707), underwent cardiovascular phenotyping with cardiac MRI (left ventricular (LV) structure and function, pulse wave velocity (PWV) and native T1 mapping) and cardiac biomarker assessment. Participants completed the incremental shuttle walk test (ISWT) and sit-to-stand 60 (STS60) as field-tests of physical function. Linear regression models identified CV determinants of physical function measures, adjusted for age, gender, BMI, diabetes, ethnicity and systolic blood pressure. Troponin I, PWV and global native T1 were univariate determinants of ISWT and STS60 performance. NT pro-BNP was a univariate determinant of ISWT performance. In multivariate models, NT pro-BNP and global native T1 were independent determinants of ISWT and STS60 performance. LV ejection fraction was an independent determinant of ISWT distance. However, age and diabetes had the strongest relationships with physical function. In conclusion, NT pro-BNP, global native T1 and LV ejection fraction were independent CV determinants of physical function. However, age and diabetes had the greatest independent influence. Targeting diabetic care may ameliorate deconditioning in these patients and a multimorbidity approach should be considered when developing exercise interventions.


Subject(s)
Cardiovascular Deconditioning , Cardiovascular Diseases/diagnosis , Exercise Tolerance , Functional Status , Health Status Indicators , Kidney Failure, Chronic/therapy , Renal Dialysis , Adult , Age Factors , Aged , Biomarkers/blood , Cardiovascular Diseases/physiopathology , Cardiovascular Diseases/therapy , Diabetes Mellitus/diagnosis , Diabetes Mellitus/physiopathology , Female , Humans , Kidney Failure, Chronic/diagnosis , Kidney Failure, Chronic/physiopathology , Magnetic Resonance Imaging, Cine , Male , Middle Aged , Multimorbidity , Natriuretic Peptide, Brain/blood , Peptide Fragments/blood , Predictive Value of Tests , Prognosis , Pulse Wave Analysis , Randomized Controlled Trials as Topic , Risk Assessment , Risk Factors , Stroke Volume , Troponin I/blood , Vascular Stiffness , Ventricular Function, Left , Walk Test
20.
Clin Transl Radiat Oncol ; 25: 61-66, 2020 Nov.
Article in English | MEDLINE | ID: mdl-33072895

ABSTRACT

Lung cancer is the leading cause of cancer mortality worldwide and most patients are unsuitable for 'gold standard' treatment, which is concurrent chemoradiotherapy. CONCORDE is a platform study seeking to establish the toxicity profiles of multiple novel radiosensitisers targeting DNA repair proteins in patients treated with sequential chemoradiotherapy. Time-to-event continual reassessment will facilitate efficient dose-finding.

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