Barriers and facilitators to participation in exercise prehabilitation before cancer surgery for older adults with frailty: a qualitative study.

BACKGROUND: Older adults with frailty are at an increased risk of adverse outcomes after surgery. Exercise before surgery (exercise prehabilitation) may reduce adverse events and improve recovery after surgery. However, adherence with exercise therapy is often low, especially in older populations. The purpose of this study was to qualitatively assess the barriers and facilitators to participating in exercise prehabilitation from the perspective of older people with frailty participating in the intervention arm of a randomized trial. METHODS: This was a research ethics approved, nested descriptive qualitative study within a randomized controlled trial of home-based exercise prehabilitation vs. standard care with older patients (≥ 60 years) having elective cancer surgery, and who were living with frailty (Clinical Frailty Scale ≥ 4). The intervention was a home-based prehabilitation program for at least 3 weeks before surgery that involved aerobic activity, strength and stretching, and nutritional advice. After completing the prehabilitation program, participants were asked to partake in a semi-structured interview informed by the Theoretical Domains Framework (TDF). Qualitative analysis was guided by the TDF. RESULTS: Fifteen qualitative interviews were completed. Facilitators included: 1) the program being manageable and suitable to older adults with frailty, 2) adequate resources to support engagement, 3) support from others, 4) a sense of control, intrinsic value, noticing progress and improving health outcomes and 5) the program was enjoyable and facilitated by previous experience. Barriers included: 1) pre-existing conditions, fatigue and baseline fitness, 2) weather, and 3) guilt and frustration when unable to exercise. A need for individualization and variety was offered as a suggestion by participants and was therefore described as both a barrier and facilitator. CONCLUSIONS: Home-based exercise prehabilitation is feasible and acceptable to older people with frailty preparing for cancer surgery. Participants identified that a home-based program was manageable, easy to follow with helpful resources, included valuable support from the research team, and they reported self-perceived health benefits and a sense of control over their health. Future studies and implementation should consider increased personalization based on health and fitness, psychosocial support and modifications to aerobic exercises in response to adverse weather conditions.

Home-based prehabilitation with exercise to improve postoperative recovery for older adults with frailty having cancer surgery: the PREHAB randomised clinical trial.

BACKGROUND: Frailty is a state of vulnerability as a result of decreased reserves. Prehabilitation may increase reserve and improve postoperative outcomes. Our objective was to determine if home-based prehabilitation improves postoperative functional recovery in older adults with frailty having cancer surgery. METHODS: This double blind randomised trial enrolled people ≥60 yr having elective cancer surgery and ≥3 weeks from enrolment to surgery as eligible. Participation in a remotely supported, home-based exercise prehabilitation program plus nutritional guidance was compared with standard care plus written advice on age-appropriate activity and nutrition. The primary outcome was 6-min walk test (6MWT) distance at the first postoperative clinic visit. Secondary outcomes included physical performance, quality of life, disability, length of stay, non-home discharge, and 30-day readmission. RESULTS: Of 543 patients assessed, 254 were eligible and 204 (80%) were randomised (102 per arm); 182 (94 intervention and 88 control) had surgery and were analysed. Mean age was 74 yr and 57% were female. Mean duration of participation was 5 weeks, mean adherence was 61% (range 0%-100%). We found no significant difference in 6MWT at follow-up (+14 m, 95% confidence interval -26-55 m, P=0.486), or for secondary outcomes. Analyses using a prespecified adherence definition of ≥80% supported improvements in 6MWT distance, complication count, and disability. CONCLUSIONS: A home-based prehabilitation program did not significantly improve postoperative recovery or other outcomes in older adults with frailty having cancer surgery. Program adherence may be a key mediator of prehabilitation efficacy. CLINICAL TRIAL REGISTRATION: NCT02934230.

Peripheral Nerve Blocks and Potentially Attributable Adverse Events in Older People with Hip Fracture: A Retrospective Population-based Cohort Study.

BACKGROUND: Peripheral nerve blocks are being used with increasing frequency for management of hip fracture-related pain. Despite converging evidence that nerve blocks may be beneficial, safety data are lacking. This study hypothesized that peripheral nerve block receipt would not be associated with adverse events potentially attributable to nerve blocks, as well as overall patient safety incidents while in hospital. METHODS: This was a preregistered, retrospective population-based cohort study using linked administrative data. This study identified all hip fracture admissions in people 50 yr of age or older and identified all nerve blocks (although we were unable to ascertain the specific anatomic location or type of block), potentially attributable adverse events (composite of seizures, fall-related injuries, cardiac arrest, nerve injury), and any patient safety events using validated codes. The study also estimated the unadjusted and adjusted association of nerve blocks with adverse events; adjusted absolute risk differences were also calculated. RESULTS: In total, 91,563 hip fracture patients from 2009 to 2017 were identified; 15,631 (17.1%) received a nerve block, and 5,321 (5.8%; 95% CI, 5.7 to 6.0%) patients experienced a potentially nerve block-attributable adverse event: 866 (5.5%) in patients with a block and 4,455 (5.9%) without a block. Before and after adjustment, nerve blocks were not associated with potentially attributable adverse events (adjusted odds ratio, 1.05; 95% CI, 0.97 to 1.15; and adjusted risk difference, 0.3%, 95% CI, -0.1 to 0.8). CONCLUSIONS: The data suggest that nerve blocks in hip fracture patients are not associated with higher rates of potentially nerve block-attributable adverse events, although these findings may be influenced by limitations in routinely collected administrative data.

The Canadian Medical Student Ultrasound Curriculum: A Statement From the Canadian Ultrasound Consensus for Undergraduate Medical Education Group.

OBJECTIVES: This study sought to establish by expert review a consensus-based, focused ultrasound curriculum, consisting of a foundational set of focused ultrasound skills that all Canadian medical students would be expected to attain at the end of the medical school program. METHODS: An expert panel of 21 point-of-care ultrasound and educational leaders representing 15 of 17 (88%) Canadian medical schools was formed and participated in a modified Delphi consensus method. Experts anonymously rated 195 curricular elements on their appropriateness to include in a medical school curriculum using a 5-point Likert scale. The group defined consensus as 70% or more experts agreeing to include or exclude an element. We determined a priori that no more than 3 rounds of voting would be performed. RESULTS: Of the 195 curricular elements considered in the first round of voting, the group reached consensus to include 78 and exclude 24. In the second round, consensus was reached to include 4 and exclude 63 elements. In our final round, with 1 additional item added to the survey, the group reached consensus to include an additional 3 and exclude 8 elements. A total of 85 curricular elements reached consensus to be included, with 95 to be excluded. Sixteen elements did not reach consensus to be included or excluded. CONCLUSIONS: By expert opinion-based consensus, the Canadian Ultrasound Consensus for Undergraduate Medical Education Group recommends that 85 curricular elements be considered for inclusion for teaching in the Canadian medical school focused ultrasound curricula.

Patient function and caregiver burden after ambulatory surgery: a cohort study of patients older than 65.

PURPOSE: The primary objective of this prospective cohort study was to assess the impact of ambulatory surgery on patient function one week and one month following surgery among surgical patients ≥ 65 yr of age. Secondary objectives were to determine whether changes in patient function were correlated with increased burden of care in the patient's primary caregiver and with patient assessments of postoperative pain and quality of life. METHODS: Following Research Ethics Board approval, patients aged ≥ 65 yr undergoing elective ambulatory surgery and their caregivers were recruited. Patients completed the système de mesure de l'autonomie fonctionnelle (SMAF) and the Brief Pain Inventory. Primary caregivers completed the Zarit Burden Interview (ZBI). All measurements were obtained preoperatively and on postoperative days (POD) 7 and 30. RESULTS: Patient function decreased on POD 7 and had not returned to baseline on POD 30 (mean change in SMAF 6.9; 95% confidence interval (CI) 5.3 to 8.4 on POD 7 and mean change in SMAF 2.6; 95% CI 1.3 to 4.0 on POD 30). Interval changes in caregiver burden were not significant (mean change in ZBI -0.4; 95% CI -1.8 to 0.96 on POD 7 and mean change in ZBI -0.6; 95% CI -2.1 to 0.8 on POD 30). Decreased patient function was associated with increased caregiver burden at all time points (P < 0.001). Decreased caregiver function at baseline was also associated with higher ZBI (linear association 0.71; P = 0.02). CONCLUSIONS: Patients exhibited reduced function seven days following ambulatory surgery. Patient function largely recovered by POD 30. Caregiver burden was variable and influenced by both patient and caregiver function. This trial was registered with Clinical Trials.gov (NCT01382251).

Comparison of student examiner to faculty examiner scoring and feedback in an OSCE.

OBJECTIVES: to help reduce pressure on faculty staff, medical students have been used as raters in objective structured clinical examinations (OSCEs). There are few studies regarding their ability to complete checklists and global rating scales, and a paucity of data on their ability to provide feedback to junior colleagues. The objectives of this study were: (i) to compare expert faculty examiner (FE) and student-examiner (SE) assessment of students' (candidates') performances on a formative OSCE; (ii) to assess SE feedback provided to candidates, and (iii) to seek opinion regarding acceptability from all participants. METHODS: year 2 medical students (candidates, n = 66) participated in a nine-station formative OSCE. Year 4 students (n = 27) acted as SEs and teaching doctors (n = 27) served as FEs. In each station, SEs and FEs independently scored the candidates using checklists and global rating scales. The SEs provided feedback to candidates after each encounter. The FEs evaluated SEs on the feedback provided using a standardised rating scale (1 = strongly disagree, 5 = strongly agree) for several categories, according to whether the feedback was: balanced; specific; accurate; appropriate; professional, and similar to feedback the FE would have provided. All participants completed questionnaires exploring perceptions and acceptability. RESULTS: there was a high correlation on the checklist items between raters on each station, ranging from 0.56 to 0.86. Correlations on the global rating for each station ranged from 0.23 to 0.78. Faculty examiners rated SE feedback highly, with mean scores ranging from 4.02 to 4.44 for all categories. There was a high degree of acceptability on the part of candidates and examiners. CONCLUSIONS: student-examiners appear to be a viable alternative to FEs in a formative OSCE in terms of their ability to both complete checklists and provide feedback.

Comparison of Clerkship Directors' Expectations of Physical Examination Skills with Point-of-care Ultrasound Skills Using the RIME Framework.

Background: The expectations of point-of-care ultrasound (PoCUS) in undergraduate clerkship at the University of Ottawa has not been described. We compared clerkship directors' expectations of physical examination skills with PoCUS skills, before and after completing the clerkship rotation. Methods: A pilot-tested, expert developed, bilingual on-line survey consisting of 15 questions was sent to all clerkship directors (23) in December 2019. The survey included questions regarding the expectations of medical students with respect to physical examination and PoCUS using the RIME Framework: none, reporter, interpreter, manager, educator. Results: The response rate was 60.9% (14/23). With regards to physical exam skills, 82.8% of directors had no expectations or expected students to be reporters when starting clerkship. At graduation, 77.5% of directors expected students to be interpreters, managers, or educators. For PoCUS, 100.0% of directors had no expectations or expected students to be reporters when starting clerkship. At clerkship completion, 33.0% of directors felt that students should be interpreters or managers for PoCUS skills. Conclusions: Clerkship directors have low expectations of PoCUS skills for entering and graduating clerks when compared with their physical examination skills despite formal pre-clerkship PoCUS objectives. Enhanced communication and targeted education of directors could improve the PoCUS curriculum.

DNA hypomethylation and human diseases.

Changes in human DNA methylation patterns are an important feature of cancer development and progression and a potential role in other conditions such as atherosclerosis and autoimmune diseases (e.g., multiple sclerosis and lupus) is being recognised. The cancer genome is frequently characterised by hypermethylation of specific genes concurrently with an overall decrease in the level of 5 methyl cytosine. This hypomethylation of the genome largely affects the intergenic and intronic regions of the DNA, particularly repeat sequences and transposable elements, and is believed to result in chromosomal instability and increased mutation events. This review examines our understanding of the patterns of cancer-associated hypomethylation, and how recent advances in understanding of chromatin biology may help elucidate the mechanisms underlying repeat sequence demethylation. It also considers how global demethylation of repeat sequences including transposable elements and the site-specific hypomethylation of certain genes might contribute to the deleterious effects that ultimately result in the initiation and progression of cancer and other diseases. The use of hypomethylation of interspersed repeat sequences and genes as potential biomarkers in the early detection of tumors and their prognostic use in monitoring disease progression are also examined.

Lab-on-a-chip in vitro compartmentalization technologies for protein studies.

In vitro compartmentalization (IVC) is a powerful tool for studying protein-protein reactions, due to its high capacity and the versatility of droplet technologies. IVC bridges the gap between chemistry and biology as it enables the incorporation of unnatural amino acids with modifications into biological systems, through protein transcription and translation reactions, in a cell-like microdrop environment. The quest for the ultimate chip for protein studies using IVC is the drive for the development of various microfluidic droplet technologies to enable these unusual biochemical reactions to occur. These techniques have been shown to generate precise microdrops with a controlled size. Various chemical and physical phenomena have been utilized for on-chip manipulation to allow the droplets to be generated, fused, and split. Coupled with detection techniques, droplets can be sorted and selected. These capabilities allow directed protein evolution to be carried out on a microchip. With further technological development of the detection module, factors such as addressable storage, transport and interfacing technologies, could be integrated and thus provide platforms for protein studies with high efficiency and accuracy that conventional laboratories cannot achieve.

Therapeutic advances in rheumatology with the use of recombinant proteins.

Antibody engineering and protein design have led to the creation of a new era of targeted anti-inflammatory therapies in rheumatology. Recombinant DNA technologies have enabled the selection and humanization of specific antibody fragments in order to develop therapeutic reagents of any specificity that can be 'armed' to deliver effective anti-inflammatory 'payloads'. Antibodies and antibody-like proteins provide the opportunity to block key soluble mediators of inflammation in their milieu, or alternatively to block intracellular inflammation-triggering pathways by binding to an upstream cell-surface receptor. These designer proteins can be tuned for desired pharmacokinetic and pharmacodynamic effects, and represent tools for specific therapeutic intervention by delivering precisely the required immunosuppressive effect. The extent of desired and undesired effects of a particular biologic therapy, however, can be broader than initially predicted and require careful evaluation during clinical trials. This Review highlights advances in recombinant technologies for the development of novel biologic therapies in rheumatology.

PREHAB study: a protocol for a prospective randomised clinical trial of exercise therapy for people living with frailty having cancer surgery.

INTRODUCTION: Exercise prehabilitation may improve outcomes after surgery. Frailty is a key predictor of adverse postoperative outcomes in older people; the multidimensional nature of frailty makes this a population who may derive substantial benefit from exercise prehabilitation. The objective of this trial is to test the efficacy of exercise prehabilitation to improve postoperative functional outcomes for people living with frailty having cancer surgery with curative intent. METHODS AND ANALYSIS: We will conduct a single-centre, parallel-arm randomised controlled trial of home-based exercise prehabilitation versus standard care among consenting patients >60 years having elective cancer surgery (intra-abdominal and intrathoracic) and who are frail (Clinical Frailty Scale >4). The intervention consists of > 3 weeks of exercise prehabilitation (strength, aerobic and stretching). The primary outcome is the 6 min walk test at the first postoperative clinic visit. Secondary outcomes include the short physical performance battery, health-related quality of life, disability-free survival, complications and health resource utilisation. The primary outcome will be analysed by intention to treat using analysis of covariance. Outcomes up to 1 year after surgery will be ascertained through linkage to administrative data. ETHICS AND DISSEMINATION: Ethical approval has been granted by our ethics review board (Protocol Approval #2016009-01H). Results will be disseminated through presentation at scientific conferences, through peer-reviewed publication, stakeholder organisations and engagement of social and traditional media. TRIAL REGISTRATION NUMBER: NCT02934230; Pre-results.

In vitro display technologies reveal novel biopharmaceutics.

Display technologies are fundamental to the isolation of specific high-affinity binding proteins for diagnostic and therapeutic applications in cancer, neurodegenerative, and infectious diseases as well as autoimmune and inflammatory disorders. Applications extend into the broad field of antibody (Ab) engineering, synthetic enzymes, proteomics, and cell-free protein synthesis. Recently, in vitro display technologies have come to prominence due to the isolation of high-affinity human antibodies by phage display, the development of novel scaffolds for ribosome display, and the discovery of novel protein-protein interactions. In vitro display represents an emerging and innovative technology for the rapid isolation and evolution of high-affinity peptides and proteins. So far, only one clinical drug candidate produced by in vitro display technology has been approved by the FDA for use in humans, but several are in clinical or preclinical testing. This review highlights recent advances in various engineered biopharmaceutical products isolated by in vitro display with a focus on the commercial developments.

Selection of human anti-CD28 scFvs from a T-NHL related scFv library using ribosome display.

Engineered antibodies have become an invaluable source of biopharmaceuticals against a wide range of diseases. About 200 antibody-based biologicals have been tested in clinical trials. Single chain variable fragments of antibodies (scFvs) provide binding specificity and offer an increased ease of in vitro display selection. Here, we present the generation of a human scFv library from peripheral blood lymphocyte RNA of a patient with relapsed T-cell non-Hodgkin lymphoma (T-NHL) who experienced a rare case of "spontaneous" remission. Antibodies against human T-cell antigen CD28, a co-stimulatory protein that influences the immune response by amplification of the transcriptional effects of T-cell receptors, might have contributed to the patient's remission. The scFv library was panned against CD28 using ribosome display and further subjected to affinity maturation. Isolated scFv were assessed for binding specificity and affinity and may provide the basis for the development of novel immunotherapeutic strategies. This work demonstrates the selection of a fully human antibody fragment from a patient-derived gene pool by in vitro ribosome display technology.

Driving and Dementia: Workshop Module on Communicating Cessation to Drive.

BACKGROUND: For persons with dementia (PWD), driving becomes very dangerous. Physicians in Canada are legally responsible to report unfit drivers and then must disclose that decision to their patients. That difficult discussion is fraught with challenges: physicians want to maintain a healthy relationship; patients often lack insight into their cognitive loss and have very strong emotional reactions to the loss of their driving privileges. All of which may stifle the exchange of accurate information. The goal of this project was to develop a multimedia module that would provide strategies and support for health professionals having these difficult conversations. METHODS: Literature search was conducted of Embase and OVID MedLine on available driving and dementia tools, and on websites of online tools for communication strategies on driving cessation. A workshop module was developed with background material, communication strategies, links to resources and two videos demonstrating the "bad" then the "good" ways of managing this emotionally charged discussion. RESULTS: When the module was tested with internal medicine trainees, results demonstrated that confidence increased significantly (p < .001), and comfort and willingness in discussing the subject improved. CONCLUSION: This project demonstrated the positive impact of the module on improving health professionals' attitude and readiness to communicate driving cessation to PWD.

Novel proteins in emulsions using in vitro compartmentalization.

IVC (in vitro compartmentalization) provides a complete cell-free approach for the production of novel targeted proteins. IVC uses aqueous droplets, which contain DNA and components for protein production, within water-in-oil emulsions. Recent advances in the composition and formation, as well as the detection, sorting and recovery, of the droplets enable the evolution of the encoded protein. Furthermore, IVC technology permits the step-wise addition of reagents into the droplets, making them suitable for high-throughput applications - where synthetic enzymes with substrate specificity are selected for catalytic activity, binding and regulation. In the broad field of in vitro display, developments such as the incorporation of unnatural amino acids and the production of cell toxic proteins expand the diverse spectrum of future applications for IVC.

A new generation of protein display scaffolds for molecular recognition.

Engineered antibodies and their fragments are invaluable tools for a vast range of biotechnological and pharmaceutical applications. However, they are facing increasing competition from a new generation of protein display scaffolds, specifically selected for binding virtually any target. Some of them have already entered clinical trials. Most of these nonimmunoglobulin proteins are involved in natural binding events and have amazingly diverse origins, frameworks, and functions, including even intrinsic enzyme activity. In many respects, they are superior over antibody-derived affinity molecules and offer an ever-extending arsenal of tools for, e.g., affinity purification, protein microarray technology, bioimaging, enzyme inhibition, and potential drug delivery. As excellent supporting frameworks for the presentation of polypeptide libraries, they can be subjected to powerful in vitro or in vivo selection and evolution strategies, enabling the isolation of high-affinity binding reagents. This article reviews the generation of these novel binding reagents, describing validated and advanced alternative scaffolds as well as the most recent nonimmunoglobulin libraries. Characteristics of these protein scaffolds in terms of structural stability, tolerance to multiple substitutions, ease of expression, and subsequent applications as specific targeting molecules are discussed. Furthermore, this review shows the close linkage between these novel protein tools and the constantly developing display, selection, and evolution strategies using phage display, ribosome display, mRNA display, cell surface display, or IVC (in vitro compartmentalization). Here, we predict the important role of these novel binding reagents as a toolkit for biotechnological and biomedical applications.

The crystal structure of an anti-CEA scFv diabody assembled from T84.66 scFvs in V(L)-to-V(H) orientation: implications for diabody flexibility.

Diabodies (scFv dimers) are small, bivalent antibody mimetics of approximately 55kDa in size that possess rapid in vivo targeting pharmacokinetics compared to the intact parent antibody, and may prove highly suitable for imaging and therapeutic applications. Here, we describe T84.66Di, the first diabody crystal structure in which the scFvs comprise V domains linked in the V(L)-to-V(H) orientation. The structure was determined by X-ray diffraction analysis to 2.6 A resolution. The T84.66Di scFv was constructed from the anti-carcinoembryonic antigen (anti-CEA) antibody T84.66 variable domains connected by an eight residue peptide linker to provide flexibility between Fv modules and promote dimer formation with bivalent affinity to the cell-surface target, CEA. Therefore, it was surprising to observe a close association of some Fv module complementarity-determining regions in the T84.66 diabody crystal, especially compared to other diabody structures all of which are linked in the opposite V(H)-to-V(L) orientation. The differences between the arrangement of Fv modules in the T84.66Di V(L)-to-V(H) linked diabody structure compared to the crystal structure of L5MK16 and other proposed V(H)-to-V(L) linked diabodies has been investigated and their potential for flexibility discussed. The comparison between V(H)-to-V(L) and V(L)-to-V(H) linked diabodies revealed in this study represents a limited repertoire of possible diabody Fv orientations, but one that reveals the potential flexibility of these molecules. This analysis therefore provides some signposts that may impact on future molecular designs for these therapeutic molecules with respect to diabody flexibility and avidity.

Noncovalent scFv multimers of tumor-targeting anti-Lewis(y) hu3S193 humanized antibody.

Single-chain variable fragments (scFvs) of anti-Lewis(y) hu3S193 humanized antibody were constructed by joining the V(H) and V(L) domains with either +2 residues, +1 residue, or by directly linking the domains. In addition two constructs were synthesized in which one or two C-terminal residues of the V(H) domain were removed (-1 residue, -2 residue) and then joined directly to the V(L) domain. An scFv construct in the reverse orientation with the V(L) joined directly to the V(H) domain was also synthesized. Upon transformation into Escherichia coli all scFv constructs expressed active protein. Binding activity, multimeric status, and multivalent properties were assessed by flow cytometry, size exclusion chromatography, and biosensor analysis. The results for hu3S193 scFvs are consistent with the paradigm that scFvs with a linker of +3 residues or more associate to form a non-covalent dimer, and those with a shorter linker or directly linked associate predominantly to form a non-covalent trimer and tetramer that are in equilibrium. While the association of V domains to form either a dimer or trimer/tetramer is governed by the length of the linker, the stability of the trimer/tetramer in the equilibrium mixture is dependent on the affinity of the interaction of the individual V domains to associate to form the larger Fv module.

Large-scale bacterial fermentation and isolation of scFv multimers using a heat-inducible bacterial expression vector.

This protocol describes optimised large-scale bacterial fermentation conditions for recombinant single-chain Fv molecule (scFv) monomers and multimers (diabodies and triabodies). The heat-inducible bacterial secretion vector, pPOW3, utilising the temperature-regulated tandem lambda promoters is particularly suited to the large-scale fermentation of single-chain antibodies, providing low-cost recombinant protein synthesis. The protein expressed by this vector is secreted into the periplasm where it is found as both the soluble and insoluble protein that is associated with the cell membranes. A protein fractionation method for the rapid extraction and affinity purification of the soluble protein fraction and the urea solubilization and refolding of the insoluble protein fraction expressed from single-chain antibody (Ab) fragment gene constructs is described. This method is simple to perform and utilises inexpensive reagents to provide cost-effective protein synthesis.