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1.
J Vis Exp ; (206)2024 Apr 12.
Article En | MEDLINE | ID: mdl-38682942

Mitochondria serve many important functions, including cellular respiration, ATP production, controlling apoptosis, and acting as a central hub of metabolic pathways. Therefore, experimentally assessing mitochondrial functionality can provide insight into variations among different populations or disease states. Additionally, it is valuable to assess whether isolated mitochondria are healthy enough to proceed with experiments. One characteristic often used to compare mitochondrial function in different samples is the rate of oxygen consumption. Oxygen consumption and subsequent calculation of the respiratory control ratio in either intact cells or mitochondria isolated from tissue can serve all three purposes. Using mitochondria isolated from the livers of brush lizards in conjunction with a phosphorescent probe that is sensitive to the fluctuations in oxygen concentration of a solution, we measured oxygen consumption using a fluorescent plate reader. This method is not only quick and efficient but also can be conducted with a small amount of mitochondria and without the need for specialized equipment. The step-by-step protocol described here increases the accessibility of mitochondrial functional assessment to researchers.


Oxygen Consumption , Animals , Oxygen Consumption/physiology , Lizards/metabolism , Mitochondria, Liver/metabolism , Fluorescent Dyes/chemistry , Mitochondria/metabolism
2.
Biochem Mol Biol Educ ; 52(1): 58-69, 2024.
Article En | MEDLINE | ID: mdl-37815098

We present as a case study the evolution of a series of participant-centered workshops designed to meet a need in the life sciences education community-the incorporation of best practices in the assessment of student learning. Initially, the ICABL (Inclusive Community for the Assessment of Biochemistry and Molecular Biology/BMB Learning) project arose from a grass-roots effort to develop material for a national exam in biochemistry and molecular biology. ICABL has since evolved into a community of practice in which participants themselves-through extensive peer review and reflection-become integral stakeholders in the workshops. To examine this evolution, this case study begins with a pilot workshop supported by seed funding and thoughtful programmatic assessment, the results of which informed evidence-based changes that, in turn, led to an improved experience for the community. Using participant response data, the case study also reveals critical features for successful workshops, including participant-centered activities and the value of frequent peer review of participants' products. Furthermore, we outline a train-the-trainer model for creating a self-renewing community by bringing new perspectives and voices into an existing core leadership team. This case study, then, offers a blueprint for building a thriving, evolving community of practice that not only serves the needs of individual scientist-educators as they seek to enhance student learning, but also provides a pathway for elevating members to positions of leadership.


Physicians , Students , Humans , Biochemistry/education , Molecular Biology/education , Learning
4.
Physiol Biochem Zool ; 95(6): 536-543, 2022.
Article En | MEDLINE | ID: mdl-36179356

AbstractPigments such as melanin are most often associated with the surface of an organism, providing functions such as coloration and protection from UV radiation. However, the internal organs of some species also contain melanin. Internal melanin may also perform protective functions when cellular stress is experienced. We tested liver tissue of two tree lizard species that experienced introgression of their mitochondria to see whether melanin was present and whether it was at higher concentrations in the types of lizards thought to be under cellular stress. Previous work found that mitochondria from livers of hybrid tree lizards (those with introgressed mitochondrial DNA) had higher levels of ATP production at higher temperatures than both parental species and showed indications of dysfunction. Therefore, we predicted that if internal melanin functions to mediate the impact of damaging by-products of metabolism, such as excessive reactive oxygen species (ROS), melanin would be highest in livers of lizards with introgressed mitochondria. To test this, we used a melanin-specific stain on liver tissue sections and measured melanin concentration with spectrophotometry of heavy-membrane fractions from whole-liver homogenates of both parental species and their hybrids with introgressed mitochondria. Slides of liver sections treated with a melanin-specific stain revealed that hybrids contained melanin and had significantly higher levels of it than either parental species. Spectrophotometry gave the same result. This distribution of internal melanin matches the pattern expected if melanin functions as a compensatory mechanism to deal with higher ATP production and the subsequent high levels of ROS expected in these hybrid lizards. Future studies will examine this mechanistically.


Lizards , Adenosine Triphosphate , Animals , DNA, Mitochondrial/genetics , Liver/metabolism , Lizards/genetics , Melanins , Reactive Oxygen Species/metabolism
5.
Vet Parasitol ; 304: 109699, 2022 Apr.
Article En | MEDLINE | ID: mdl-35390642

The horn fly, Haematobia irritans, is a blood-feeding parasitic fly with a global distribution that includes Europe, Africa, Asia, and the Americas. The fly has a major detrimental economic impact upon cattle production, with losses estimated at over $800 million annually in the United States and $2.5 billion in Brazil alone. Insecticide resistance in specific horn fly populations has been a problem for many years and there are several mechanisms whereby resistance develops. Little is known about the complement of metabolic enzymes encoded by the horn fly's genome that might provide the fly with detoxification or sequestration pathways to survive insecticide treatments. The cytochrome P450, glutathione S-transferase, and esterase enzyme families contain members that are capable of sequestering and/or detoxifying xenobiotic molecules such as insecticides. We sought to develop a comprehensive dataset of metabolic enzyme-encoding transcript sequences from the adult horn fly, as this is the life stage whose actions directly impose the economic costs to cattle producers. We used an Illumina paired-end read RNA-Seq approach to determine the adult horn fly transcriptomes from laboratory and field populations of horn flies with varying levels of pesticide resistance, including untreated and pyrethroid-treated newly eclosed adult flies. We followed with bioinformatic analyses to discern sequences putatively encoding cytochrome P450, esterase, and GST enzymes. We utilized read-mapping of RNA-Seq data and quantitative real-time polymerase chain reaction (qRT-PCR) to examine gene expression levels of specific P450 transcripts in several fly populations with varying degrees of pesticide resistance.


Insecticides , Muscidae , Animals , Cattle , Cytochrome P-450 Enzyme System/genetics , Esterases/genetics , Glutathione , Humans , Insecticide Resistance/genetics , Insecticides/pharmacology , Muscidae/genetics , Transcriptome , Transferases/genetics
6.
Diabet Med ; 39(5): e14715, 2022 05.
Article En | MEDLINE | ID: mdl-34637553

Commercial hybrid closed-loop systems are becoming more readily available, yet the number of DIY artificial pancreas system (DIY APS) users continues to rise. These DIY systems have not gone through the usual regulatory approvals processes, and, thus, present a number of legal difficulties for a number of actors, including clinicians, parents who build DIY APS for their children, and users themselves. These issues have so far received insufficient attention. Due to the complex constellation of actors involved in both development of DIY APSs and in its deployment, it is not currently clear who, and to what extent, different parties might (successfully) be held liable if something goes wrong. Despite this uncertainty, unless and until clearer guidance is issued by relevant bodies, or a case appears before the courts which clarifies the situation, existing legal principles apply. In this article, we examine some of these to shed light on how the law would likely be applied if harm were to result from the use of a DIY APS.


Diabetes Mellitus, Type 1 , Pancreas, Artificial , Child , Diabetes Mellitus, Type 1/drug therapy , Humans , Insulin Infusion Systems , Parents
7.
Health Expect ; 25(5): 2095-2106, 2022 10.
Article En | MEDLINE | ID: mdl-34420254

OBJECTIVE: This study aimed to develop interpretive insights concerning Infection Prevention and Control (IPC) in care homes for older people. DESIGN: This study had a meta-ethnography design. DATA SOURCES: Six bibliographic databases were searched from inception to May 2020 to identify the relevant literature. REVIEW METHODS: A meta-ethnography was performed. RESULTS: Searches yielded 652 records; 15 were included. Findings were categorized into groups: The difficulties of enacting IPC measures in the care home environment; workload as an impediment to IPC practice; the tension between IPC and quality of life for care home residents; and problems dealing with medical services located outside the facility including diagnostics, general practice and pharmacy. Infection was revealed as something seen to lie 'outside' the control of the care home, whether according to origins or control measures. This could help explain the reported variability in IPC practice. Facilitators to IPC uptake involved repetitive training and professional development, although such opportunities can be constrained by the ways in which services are organized and delivered. CONCLUSIONS: Significant challenges were revealed in implementing IPC in care homes including staffing skills, education, workloads and work routines. These challenges cannot be properly addressed without resolving the tension between the objectives of maintaining resident quality of life while enacting IPC practice. Repetitive staff training and professional development with parallel organisational improvements have prospects to enhance IPC uptake in residential and nursing homes. PATIENT OR PUBLIC CONTRIBUTION: A carer of an older person joined study team meetings and was involved in writing a lay summary of the study findings.


Nursing Homes , Quality of Life , Humans , Aged , Qualitative Research , Delivery of Health Care , Anthropology, Cultural
8.
Med Law Int ; 21(1): 42-68, 2021 Mar.
Article En | MEDLINE | ID: mdl-33958837

In response to slow progress regarding technological innovations to manage type 1 diabetes, some patients have created unregulated do-it-yourself artificial pancreas systems (DIY APS). Yet both in the United Kingdom (UK) and internationally, there is an almost complete lack of specific guidance - legal, regulatory, or ethical - for clinicians caring for DIY APS users. Uncertainty regarding their professional obligations has led to them being cautious about discussing DIY APS with patients, let alone recommending or prescribing them. In this article, we argue that this approach threatens to undermine trust and transparency. Analysing the professional guidance from the UK regulator - the General Medical Council - we demonstrate that nothing within it ought to be interpreted as precluding clinicians from initiating discussions about DIY APS. Moreover, in some circumstances, it may require that clinicians do so. We also argue that the guidance does not preclude clinicians from prescribing such unapproved medical devices.

9.
Article En | MEDLINE | ID: mdl-33884071

The COVID-19 pandemic has challenged undergraduate instructors and students in an unprecedented manner. Each has needed to find creative ways to continue the engaged teaching and learning process in an environment defined by physical separation and emotional anxiety and uncertainty. As a potential tool to meet this challenge, we developed a set of curricular materials that combined our respective life science teaching interests with the real-time scientific problem of the COVID-19 pandemic in progress. Discrete modules were designed that are engaging to students, implement active learning-based coursework in a variety of institutional and learning settings, and can be used either in person or remotely. The resulting interdisciplinary curriculum, dubbed "COVID-360," enables instructors to select from a menu of curricular options that best fit their course content, desired activities, and mode of class delivery. Here we describe how we devised the COVID-360 curriculum and how it represents our efforts to creatively and effectively respond to the instructional needs of diverse students in the face of an ongoing instructional crisis.

10.
CBE Life Sci Educ ; 20(2): es6, 2021 06.
Article En | MEDLINE | ID: mdl-33900121

With support from the American Society for Biochemistry and Molecular Biology (ASBMB), a community of biochemistry and molecular biology (BMB) scientist-educators has developed and administered an assessment instrument designed to evaluate student competence across four core concept and skill areas fundamental to BMB. The four areas encompass energy and metabolism; information storage and transfer; macromolecular structure, function, and assembly; and skills including analytical and quantitative reasoning. First offered in 2014, the exam has now been administered to nearly 4000 students in ASBMB-accredited programs at more than 70 colleges and universities. Here, we describe the development and continued maturation of the exam program, including the organic role of faculty volunteers as drivers and stewards of all facets: content and format selection, question development, and scoring.


Biochemistry , Students , Biochemistry/education , Certification , Humans , Molecular Biology/education , Universities
11.
Med Law Rev ; 28(4): 675-695, 2020 Dec 17.
Article En | MEDLINE | ID: mdl-33083836

Discharges from hospital are internationally recognised as a dangerous time in the care pathway of a patient, posing a risk to both their physical wellbeing and dignity. This article examines the effectiveness of risk-based regulation as a tool to address patient safety incidents linked to the hospital discharge process within the English National Health Service. It examines how the risk of this process is identified, conceptualised, and prioritised amongst the relevant statutory regulators, and argues that the risk is neither uniformly recognised by the statutory regulators within the English NHS, nor sufficiently addressed. Professional regulators in particular appear to have a poor awareness of the risk and their role in addressing it. Until these issues are resolved, patients leaving hospitals will continue to be exposed to patient safety incidents which should be avoidable.


Patient Discharge/legislation & jurisprudence , Patient Discharge/standards , Patient Safety/legislation & jurisprudence , Patient Safety/standards , Risk Management/legislation & jurisprudence , Risk Management/standards , England , Humans , National Health Programs
13.
J Cardiovasc Dev Dis ; 7(1)2019 Dec 18.
Article En | MEDLINE | ID: mdl-31861331

Studies in mice show a brief neonatal period of cardiac regeneration with minimal scar formation, but less is known about reparative mechanisms in large mammals. A transient cardiac injury approach (ischemia/reperfusion, IR) was used in weaned postnatal day (P)30 pigs to assess regenerative repair in young large mammals at a stage when cardiomyocyte (CM) mitotic activity is still detected. Female and male P30 pigs were subjected to cardiac ischemia (1 h) by occlusion of the left anterior descending artery followed by reperfusion, or to a sham operation. Following IR, myocardial damage occurred, with cardiac ejection fraction significantly decreased 2 h post-ischemia. No improvement or worsening of cardiac function to the 4 week study end-point was observed. Histology demonstrated CM cell cycling, detectable by phospho-histone H3 staining, at 2 months of age in multinucleated CMs in both sham-operated and IR pigs. Inflammation and regional scar formation in the epicardial region proximal to injury were observed 4 weeks post-IR. Thus, pigs subjected to cardiac IR at P30 show myocardial damage with a prolonged decrease in cardiac function, formation of a regional scar, and increased inflammation, but do not regenerate myocardium even in the presence of CM mitotic activity.

14.
BMJ Open ; 9(6): e024982, 2019 06 19.
Article En | MEDLINE | ID: mdl-31221867

OBJECTIVES: This review aimed to identify mechanisms underlying participation in falls prevention interventions, in older adults with cognitive impairment. In particular we studied the role of motivation. DESIGN: A realist review of the literature. DATA SOURCES: EMBASE, MEDLINE, CINAHL, the Cochrane Library, PsycINFO and PEDRO. ELIGIBILITY CRITERIA: Publications reporting exercise-based interventions for people with cognitive impairment, including dementia, living in the community. DATA EXTRACTION AND SYNTHESIS: A 'rough programme theory' (a preliminary model of how an intervention works) was developed, tested against findings from the published literature and refined. Data were collected according to elements of the programme theory and not isolated to outcomes. Motivation emerged as a key element, and was prioritised for further study. RESULTS: An individual will access mechanisms to support participation when they think that exercise will be beneficial to them. Supportive mechanisms include having a 'gate-keeper', such as a carer or therapist, who shares responsibility for the perception of exercise as beneficial. Lack of access to support decreases adherence and participation in exercise. Motivational mechanisms were particularly relevant for older adults with mild-to-moderate dementia, where the exercise intervention was multicomponent, in a preferred setting, at the correct intensity and level of progression, correctly supported and considered, and flexibly delivered. CONCLUSION: Motivation is a key element enabling participation in exercise-based interventions for people with cognitive impairment. Many of the mechanisms identified in this review have parallels in motivational theory. Clinically relevant recommendations were derived and will be used to further develop and test a motivationally considered exercise-based falls intervention for people with mild dementia. PROSPERO REGISTRATION NUMBER: CRD42015030169.


Accidental Falls/prevention & control , Cognitive Dysfunction/complications , Exercise , Motivation , Aged , Humans
16.
BMJ Open ; 9(2): e024185, 2019 02 22.
Article En | MEDLINE | ID: mdl-30798309

OBJECTIVES: Rehabilitation interventions for older adults are complex as they involve a number of interacting components, have multiple outcomes of interest and are influenced by a number of contextual factors. The importance of rigorous intervention development prior to formal evaluation has been acknowledged and a number of frameworks have been developed. This review explored which frameworks have been used to guide the development of rehabilitation interventions for older adults. DESIGN: Systematic scoping review. SETTING: Studies were not limited for inclusion based on setting. PARTICIPANTS: Studies were included that featured older adults (>65 years of age). INTERVENTIONS: Studies were included that reported the development of a rehabilitation intervention. PRIMARY AND SECONDARY OUTCOME MEASURES: Data were extracted on study population, setting, type of intervention developed and frameworks used. The primary outcome of interest was the type of intervention development framework. RESULTS: Thirty-five studies were included. There was a range of underlying medical conditions including mild cognitive impairment and dementia (n=5), cardiac (n=4), stroke (n=3), falls (n=3), hip fracture (n=2), diabetes (n=2), breast cancer (n=1), Parkinson's disease (n=1), depression (n=1), chronic health problems (n=1), osteoarthritis (n=1), leg ulcer (n=1), neck pain (n=1) and foot problems (n=1). The intervention types being developed included multicomponent, support based, cognitive, physical activities, nursing led, falls prevention and occupational therapy led. Twelve studies (34%) did not report using a framework. Five frameworks were reported with the Medical Research Council (MRC) framework for developing and evaluating complex interventions being the most frequently cited (77%, n=17). CONCLUSION: At present, the MRC framework is the most popular for developing rehabilitation interventions for older adults. Many studies do not report using a framework. Further, specific guidance to assist this complex field of rehabilitation research is required.


Rehabilitation/methods , Age Factors , Aged , Humans
18.
Physiol Biochem Zool ; 91(5): 1068-1081, 2018.
Article En | MEDLINE | ID: mdl-30179526

Mitochondria play a key role in the ecology and evolution of species through their influence on aerobic metabolism. Mitochondrial DNA (mtDNA) and nuclear genomes must interact for optimal functioning of oxidative phosphorylation to produce ATP, and breakdown of coadaptation components from each may have important evolutionary consequences for hybridization. Introgression of mitochondria in natural populations through hybridization with unidirectional backcrossing allows the testing of coadaptation of mitochondria to different nuclear backgrounds. We compared the function of mitochondria isolated from two species of Urosaurus lizards and hybrid populations. Due to past introgression, hybrids contain the nuclear genome of the "hot-adapted" species (U. graciosus) but the mtDNA of the less heat-tolerant species (U. ornatus). It was found that the function of the parental forms of mitochondria had significantly diverged with the hot-adapted species. There was significant genotype × genotype × environment interactions for mitochondrial membrane potential and genotype × genotype interactions for ATP production. Membrane potential decreased less at a higher temperature, while ATP production was higher at both temperatures in introgressed mitochondria. Oxygen consumption was lower in U. graciosus than in U. ornatus parental-type mitochondria, indicating a likely response to living in hotter environments. Respiratory control ratio values, which provide an indication of the functional quality of isolated mitochondria, were lower in introgressed mitochondria than in parental U. ornatus types, indicating a negative impact on biological function in introgressed mitochondria.


Biological Coevolution , Lizards/genetics , Lizards/physiology , Mitochondria/physiology , Animals , Body Temperature , Genome , Hot Temperature , Mitochondria/genetics
19.
Am J Physiol Heart Circ Physiol ; 315(4): H826-H837, 2018 10 01.
Article En | MEDLINE | ID: mdl-29979626

Age represents a major risk factor for multiple organ failure, including cardiac dysfunction, in patients with sepsis. AMP-activated protein kinase (AMPK) is a crucial regulator of energy homeostasis that controls mitochondrial biogenesis by activation of peroxisome proliferator-activated receptor-γ coactivator-1α and disposal of defective organelles by autophagy. We investigated whether AMPK dysregulation contributes to age-dependent cardiac injury in young (2-3 mo) and mature adult (11-13 mo) male mice subjected to sepsis by cecal ligation and puncture and whether AMPK activation by 5-amino-4-imidazole carboxamide riboside affords cardioprotective effects. Plasma proinflammatory cytokines and myokine follistatin were similarly elevated in vehicle-treated young and mature adult mice at 18 h after sepsis. However, despite equivalent troponin I and T levels compared with similarly treated young mice, vehicle-treated mature adult mice exhibited more severe cardiac damage by light and electron microscopy analyses with more marked intercellular edema, inflammatory cell infiltration, and mitochondrial derangement. Echocardiography revealed that vehicle-treated young mice exhibited left ventricular dysfunction after sepsis, whereas mature adult mice exhibited a reduction in stroke volume without apparent changes in load-dependent indexes of cardiac function. At molecular analysis, phosphorylation of the catalytic subunits AMPK-α1/α2 was associated with nuclear translocation of peroxisome proliferator-activated receptor-γ coactivator-1α in vehicle-treated young but not mature adult mice. Treatment with 5-amino-4-imidazole carboxamide riboside ameliorated cardiac architecture derangement in mice of both ages. These cardioprotective effects were associated with attenuation of the systemic inflammatory response and amelioration of cardiac dysfunction in young mice only, not in mature adult animals. NEW & NOTEWORTHY Our data suggest that sepsis-induced cardiac dysfunction manifests with age-dependent characteristics, which are associated with a distinct regulation of AMP-activated protein kinase-dependent metabolic pathways. Consistent with this age-related deterioration, pharmacological activation of AMP-activated protein kinase may afford cardioprotective effects allowing a partial recovery of cardiac function in young but not mature age.


AMP-Activated Protein Kinases/metabolism , Aminoimidazole Carboxamide/analogs & derivatives , Enzyme Activators/pharmacology , Myocardium/enzymology , Ribonucleotides/pharmacology , Sepsis/drug therapy , Ventricular Dysfunction, Left/prevention & control , Ventricular Function, Left/drug effects , Age Factors , Aminoimidazole Carboxamide/pharmacology , Animals , Cytokines/blood , Disease Models, Animal , Enzyme Activation , Follistatin/blood , Inflammation Mediators/blood , Male , Mice, Inbred C57BL , Myocardium/ultrastructure , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha/metabolism , Phosphorylation , Sepsis/enzymology , Sepsis/microbiology , Sepsis/physiopathology , Signal Transduction/drug effects , Troponin/blood , Ventricular Dysfunction, Left/enzymology , Ventricular Dysfunction, Left/microbiology , Ventricular Dysfunction, Left/physiopathology
20.
Clin Rehabil ; 32(7): 855-864, 2018 Jul.
Article En | MEDLINE | ID: mdl-29436253

This series of articles for rehabilitation in practice aims to cover a knowledge element of the rehabilitation medicine curriculum. Nevertheless, they are intended to be of interest to a multidisciplinary audience. The competency addressed in this article is an understanding of how to develop an intervention for people with mild cognitive impairment and dementia to promote their independence, stability, and physical activity. INTRODUCTION: Older adults with dementia are at a high risk of falls. Standard interventions have not been shown to be effective in this patient population potentially due to poor consideration of dementia-specific risk factors. An intervention is required that addresses the particular needs of older people with dementia in a community setting. METHODS: We followed guidelines for the development of an intervention, which recommend a structured approach considering theory, evidence and practical issues. The process used 15 information sources. Data from literature reviews, clinician workshops, expert opinion meetings, patient-relative interviews, focus groups with people with dementia and clinicians, a cross-sectional survey of risk factors, a pre-post intervention study and case studies were included. Data were synthesized using triangulation to produce an intervention suitable for feasibility testing. Practical consideration of how an intervention could be delivered and implemented were considered from the outset. RESULTS: Elements of the intervention included individually tailored, dementia-appropriate, balance, strength and dual-task exercises, functional training, and activities aimed at improving environmental access, delivered using a motivational approach to support adherence and long-term continuation of activity. We focussed on promoting safe activity rather than risk or prevention of falls. CONCLUSION: We used a systematic process to develop a dementia-specific intervention to promote activity and independence while reducing falls risk in older adults with mild dementia.


Cognitive Dysfunction/rehabilitation , Dementia/rehabilitation , Occupational Therapy , Physical Therapy Modalities , Accidental Falls/prevention & control , Aged , Humans , Muscle Strength/physiology , Postural Balance/physiology , Program Development , United Kingdom
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