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1.
J Adv Nurs ; 2024 Sep 03.
Article in English | MEDLINE | ID: mdl-39227184

ABSTRACT

BACKGROUND: Early mobilisation is beneficial to support recovery among critically ill patients. The literature highlights the benefits of family engagement in early mobilisation, yet this practice remains underutilised. Effective implementation depends on understanding the key antecedents that influence family engagement in early mobilisation, specifically families' knowledge, contemplation, confidence and readiness. However, no measurement tools currently exist to assess these. Therefore, developing a psychometrically supported instrument is essential to understanding and enhancing families' factors influencing their engagement in early mobilisation. AIM: To develop and evaluate the psychometric properties of an instrument to assess families' knowledge, contemplation, confidence and readiness to engage in early mobilisation. DESIGN: A multi-site cross-sectional survey design. METHODS: Based on established psychological theory (Social Cognitive Theories and Behaviour Change Theories), an item pool was developed to assess families' knowledge, contemplation, confidence and readiness to participate in early mobilisation. To psychometrically evaluate the new tool, a multi-site cross-sectional survey was undertaken from May 2020 to June 2022 across five intensive care units in Australia. Data from 370 families of critically ill patients were used to evaluate the structural, convergent and discriminant validity as well as the reliability of the new instrument. RESULTS: Confirmatory factor analysis indicated good model fit, supporting the proposed structure. All items displayed high standardised factor loadings except one, which improved upon freeing an error covariance. Positive inter-factor correlations were moderate to strong and were substantially lower than the square root of the average variance extracted, supporting both convergent and discriminant validity, respectively. Additionally, all subscales demonstrated well to excellent reliability. CONCLUSION: The findings provide preliminary support for the multiple types of validity evidence and the reliability of the instrument. This new instrument is suitable for use in clinical and research applications to assess families' knowledge, contemplation, confidence and readiness for their engagement in early mobilisation. IMPACT: Family engagement in early mobilisation activities may have multiple benefits but it is not commonly implemented in the ICU. Factors influencing family engagement in early mobilisation are poorly understood. Influential psychological theories highlight the likely importance of knowledge, contemplation, confidence and readiness. A readily available instrument designed to assess these constructs among family members is needed to deepen research understanding and guide clinical practice. The proposed instrument is designed to measure factors influencing family engagement in early mobilisation, which may support healthcare professionals and health services to identify and tailor strategies to support family engagement in early mobilisation. REPORTING METHOD: Recommendations for reporting the results of studies of instrument and scale development and testing was followed to report this study. PATIENT OR PUBLIC CONTRIBUTION: Family members of adult critically ill patients participated in this study, and they provided the data through the survey.

2.
iScience ; 27(9): 110436, 2024 Sep 20.
Article in English | MEDLINE | ID: mdl-39262802

ABSTRACT

Abdominal and thoracic aortic aneurysms (AAAs, TAAs) remain a major cause of deaths worldwide, in part due to the lack of reliable prognostic markers or early warning signs. Sox6 has been found to regulate renin controlling blood pressure. We hypothesized that Sox6 may serve as an important regulator of the mechanisms contributing to hypertension-induced aortic aneurysms. Phenotype and laboratory-wide association scans in a clinical cohort found that SOX6 gene expression is associated with aortic aneurysm in subjects of European ancestry. Sox6 and tumor necrosis factor alpha (TNF-α) expression were upregulated in aortic tissues from patients affected by either AAA or TAA. In Sox6 knockout mice with angiotensin-II-induced AAA, we found that Sox6 plays critical role in the development and progression of AAA. Our data support a regulatory role of SOX6 in the development of hypertension-induced AAA, suggesting that Sox6 may be a therapeutic target for the treatment of aortic aneurysms.

3.
Article in English | MEDLINE | ID: mdl-39318176

ABSTRACT

AIMS: To identify the prevalence, trends, and outcomes of same-day discharge following elective percutaneous coronary intervention among six public hospitals in one Australian State. METHODS AND RESULTS: A retrospective observational research design was used. A total of 4387 cases were obtained from the State Cardiac Outcomes Registry and National Hospital Cost Data Collection. The two datasets were linked using identifiable data items. Patients were those who had elective percutaneous coronary intervention between December 2012 and December 2019 either discharged the same day of the procedure or the next day. Data were analysed using descriptive and inferential statistics. The overall same-day discharge prevalence was 6.5%, with a trend increasing from 0.2% in 2013 to 9.0% in 2019. The prevalence varied at the individual hospital level. Two hospitals did not perform same-day discharge during the study period. The remaining hospitals demonstrated variability in same-day discharge prevalence, with the highest from one hospital being 28.2% in 2019. Almost all same-day discharge patients experienced no complications during or following percutaneous coronary intervention within 24 hours. Compared to next-day discharge, same-day discharge reduced the length of stay by 18 hours and conferred an average of $3695 cost-savings per patient. CONCLUSIONS: There was limited implementation of same-day discharge in the six public hospitals contributing data to this study. Improvement in the same-day discharge rate could result in better hospital resource utilisation and reduce low-value care. Hence, strategies to implement and promote same-day discharge are warranted.

4.
bioRxiv ; 2024 Sep 09.
Article in English | MEDLINE | ID: mdl-39314272

ABSTRACT

Mitochondria are hubs of metabolism and signaling and play an important role in tumorigenesis, therapeutic resistance, and metastasis in many cancer types. Various laboratory models of cancer demonstrate the extraordinary dynamics of mitochondrial structure, but little is known about the role of mitochondrial structure in resistance to anticancer therapy. We previously demonstrated the importance of mitochondrial structure and oxidative phosphorylation in the survival of chemotherapy-refractory triple negative breast cancer (TNBC) cells. As TNBC is a highly aggressive breast cancer subtype with few targeted therapy options, conventional chemotherapies remain the backbone of early TNBC treatment. Unfortunately, approximately 45% of TNBC patients retain substantial residual tumor burden following chemotherapy, associated with abysmal prognoses. Using an orthotopic patient-derived xenograft mouse model of human TNBC, we compared mitochondrial structures between treatment-naïve tumors and residual tumors after conventional chemotherapeutics were administered singly or in combination. We reconstructed 1,750 mitochondria in three dimensions from serial block-face scanning electron micrographs, providing unprecedented insights into the complexity and intra-tumoral heterogeneity of mitochondria in TNBC. Following exposure to carboplatin or docetaxel given individually, residual tumor mitochondria exhibited significant increases in mitochondrial complexity index, area, volume, perimeter, width, and length relative to treatment-naïve tumor mitochondria. In contrast, residual tumors exposed to those chemotherapies given in combination exhibited diminished mitochondrial structure changes. Further, we document extensive intra-tumoral heterogeneity of mitochondrial structure, especially prior to chemotherapeutic exposure. These results highlight the potential for structure-based monitoring of chemotherapeutic responses and reveal potential molecular mechanisms that underlie chemotherapeutic resistance in TNBC.

5.
BMJ Open ; 14(9): e083462, 2024 Sep 26.
Article in English | MEDLINE | ID: mdl-39327052

ABSTRACT

OBJECTIVES: To pilot test a co-designed intervention that enhances patient participation in hospital discharge medication communication. DESIGN: Pilot randomised controlled trial. SETTING: One tertiary hospital. PARTICIPANTS: Patients who were ≥45 years of age; ≥1 chronic illness and ≥1 regularly prescribed medication that they manage at home were recruited between October 2022 and May 2023. Healthcare professionals on participating units completed surveys. INTERVENTION: The co-designed intervention included three websites: a medication search engine, a medication question builder and tools to facilitate medication management at home. Inpatient posters contained QR codes to provide access to these websites. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcomes were the feasibility of study processes and intervention acceptability. Feasibility of study processes was measured in terms of recruitment, fidelity, retention, missing data and contamination. Patients in the intervention group and healthcare professionals on the wards self-reported intervention acceptability. Secondary outcomes were medication understanding, use, self-efficacy and healthcare utilisation. RESULTS: 60 patients were recruited and randomised; half in each study group. The intervention was largely delivered as intended, and 99.7% of data collected was complete. In total, 16/59 (27.1%) patients were lost to follow-up 28 days after hospital discharge, and 3 patients in the usual care group reported that they saw the intervention poster prior to hospital discharge. 21 of 24 intervention group patients (87.5%) deemed the intervention acceptable, while half of the healthcare professionals (n=5, 50%) thought it was acceptable. CONCLUSIONS: We demonstrated that in a future definitive trial, intervention fidelity would be high with little missing data, and patients would likely find the intervention acceptable. Thus, a larger trial may be warranted, as the intervention is implementable and approved by patients. However, additional strategies to increase recruitment and retention of eligible participants are needed. Healthcare professionals may require more preparation for the intervention to enhance their perceptions of intervention acceptability. TRIAL REGISTRATION NUMBER: ACTRN12622001028796.


Subject(s)
Feasibility Studies , Patient Discharge , Patient Participation , Humans , Pilot Projects , Male , Female , Middle Aged , Aged , Communication
6.
Adv Physiol Educ ; 48(4): 808-817, 2024 Dec 01.
Article in English | MEDLINE | ID: mdl-39236104

ABSTRACT

Physiology is an important field for students to gain a better understanding of biological mechanisms. Yet, many students often find it difficult to learn from lectures, resulting in poor retention. Here, we utilize a learning workshop model to teach students at different levels ranging from middle school to undergraduate. We specifically designed a workshop to teach students about mitochondria-endoplasmic reticulum contact (MERC) sites. The workshop was implemented for middle school students in a laboratory setting that incorporated a pretest to gauge prior knowledge, instructional time, hands-on activities, interactive learning from experts, and a posttest. We observed that the students remained engaged during the session of interactive methods, teamed with their peers to complete tasks, and delighted in the experience. Implications for the design of future physiological workshops are further offered.NEW & NOTEWORTHY This manuscript offers a design for a workshop that utilizes blended learning to engage middle school, high school, and undergraduate students while teaching them about mitochondria-endoplasmic reticulum contact sites.


Subject(s)
Endoplasmic Reticulum , Mitochondria , Physiology , Humans , Mitochondria/physiology , Mitochondria/metabolism , Endoplasmic Reticulum/physiology , Physiology/education , Adolescent , Problem-Based Learning/methods , Students , Female , Male , Comprehension , Learning/physiology , Mitochondria Associated Membranes
7.
Thromb Haemost ; 2024 Sep 19.
Article in English | MEDLINE | ID: mdl-39299270

ABSTRACT

Background About 7% of patients with cancer-associated venous thromboembolism (CAT) develop a recurrence during anticoagulant treatment. Identification of high-risk patients may help guide treatment decisions. Aim To identify clinical predictors and develop a prediction model for on-treatment recurrent CAT. Methods For this individual patient data (IPD) meta-analysis, we used data from four randomized controlled trials evaluating low-molecular-weight heparin (LMWH) or direct oral anticoagulants (DOACs) for CAT (Hokusai VTE Cancer, SELECT-D, CLOT, and CATCH). The primary outcome was adjudicated on-treatment recurrent CAT during 6-month follow-up. A clinical prediction model was developed using multivariable logistic regression analysis with backward selection. This model was validated using internal-external cross validation. Performance was assessed by the c-statistic and a calibration plot. Results After excluding patients using vitamin K antagonists, the combined dataset comprised 2,245 patients with cancer and acute CAT who were treated with edoxaban (23%), rivaroxaban (9%), dalteparin (47%), or tinzaparin (20%). Recurrent on-treatment CAT during 6-month follow-up occurred in 150 (6.7%) patients. Predictors included in the final model were age (restricted cubic spline), breast cancer (OR 0.42; 95%-CI 0.20-0.87), metastatic disease (OR 1.44; 95%-CI 1.01-2.05), treatment with DOAC (OR 0.66; 95%-CI 0.44-0.98), and deep vein thrombosis only as index event (OR 1.72; 95%-CI 1.31-2.27). The c-statistic of the model was 0.63 (95%-CI 0.54-0.72) after internal-external cross validation. Calibration varied across studies. Conclusions The prediction model for recurrent CAT included five clinical predictors and has only modest discrimination. Prediction of recurrent CAT at the initiation of anticoagulation remains challenging.

8.
Disaster Med Public Health Prep ; 18: e136, 2024 Sep 18.
Article in English | MEDLINE | ID: mdl-39291333

ABSTRACT

OBJECTIVE: The aim of this review is to identify, evaluate, and graphically display gaps in the literature related to scarce health resource allocation in humanitarian aid settings. METHODS: A systematic search strategy was utilized in MEDLINE (via Ovid), Scopus, EMBASE, CINAHL Complete, and ProQuest Central. Articles were reviewed by 2 reviewers with a third reviewer remedying any screening conflicts. Articles meeting inclusion criteria underwent data extraction to facilitate evaluation of the scope, nature, and quality of experience-based evidence for health resource allocation in humanitarian settings. Finally, articles were mapped on a matrix to display evidence graphically. RESULTS: The search strategy identified 6093 individual sources, leaving 4000 for screening after removal of duplicates. Following full-text screening, 12 sources were included. Mapping extracted data according to surge capacity domains demonstrated that all 4 domains were reflected most of all the staff domain. Much of the identified data was presented without adhering to a clear structure or nomenclature. Finally, the mapping suggested potential incompleteness of surge capacity constructs in humanitarian response settings. CONCLUSIONS: Through this review, we identified a gap in evidence available to address challenges associated with scarce resource allocation in humanitarian settings. In addition to presenting the distribution of existing literature, the review demonstrated the relevance of surge capacity and resource allocation principles underpinning the developed framework.


Subject(s)
Altruism , Resource Allocation , Humans , Resource Allocation/methods , Resource Allocation/standards , Relief Work/statistics & numerical data , Evidence Gaps
9.
Aust Crit Care ; 2024 Aug 05.
Article in English | MEDLINE | ID: mdl-39107155

ABSTRACT

BACKGROUND: Early mobilisation interventions play a role in preventing intensive care unit-acquired weakness in critically ill patients and may contribute to improved recovery. Patient-and-family-centred care includes collaborative partnerships between healthcare professionals and families and is a potential strategy to promote early mobilisation in critical care; however, we currently do not know family member preferences for partnering and involvement in early mobilisation interventions. OBJECTIVES: The objective of this study was to explore family member perspectives on the acceptability and feasibility of partnering with healthcare professionals in early mobilisation interventions for adult critically ill patients. METHODS: A descriptive qualitative design. Semistructured interviews were conducted with family members of adult critically ill patients admitted to an intensive care unit. Data were collected through individual audio-recorded interviews. Interview data were analysed using the six phases of thematic analysis described by Braun and Clark. This study is reported following the Consolidated Criteria for Reporting Qualitative Research guidelines. RESULTS: Most family members of critically ill patients found the idea of partnering with healthcare professionals in early mobilisation interventions acceptable and feasible, although none had ever considered a partnership before. Participants thought their involvement in early mobilisation would have a positive impact on both the patient's and their own wellbeing. Themes uncovered showed that understanding family-member readiness and their need to feel welcome and included in the unfamiliar critical care environment are required before family member and healthcare professional partnerships in early mobilisation interventions can be enacted. CONCLUSIONS: Family members found partnering with healthcare professionals in early mobilisation interventions acceptable and feasible to enact, but implementation is influenced by their readiness and sense of belonging.

10.
J Cell Physiol ; 2024 Aug 13.
Article in English | MEDLINE | ID: mdl-39138923

ABSTRACT

The physical characteristics of brown adipose tissue (BAT) are defined by the presence of multilocular lipid droplets (LDs) within the brown adipocytes and a high abundance of iron-containing mitochondria, which give it its characteristic color. Normal mitochondrial function is, in part, regulated by organelle-to-organelle contacts. For example, the contact sites that mediate mitochondria-LD interactions are thought to have various physiological roles, such as the synthesis and metabolism of lipids. Aging is associated with mitochondrial dysfunction, and previous studies show that there are changes in mitochondrial structure and the proteins that modulate organelle contact sites. However, how mitochondria-LD interactions change with aging has yet to be fully clarified. Therefore, we sought to define age-related changes in LD morphology and mitochondria-lipid interactions in BAT. We examined the three-dimensional morphology of mitochondria and LDs in young (3-month) and aged (2-year) murine BAT using serial block face-scanning electron microscopy and the Amira program for segmentation, analysis, and quantification. Our analyses showed reductions in LD volume, area, and perimeter in aged samples in comparison to young samples. Additionally, we observed changes in LD appearance and type in aged samples compared to young samples. Notably, we found differences in mitochondrial interactions with LDs, which could implicate that these contacts may be important for energetics in aging. Upon further investigation, we also found changes in mitochondrial and cristae structure for the mitochondria interacting with LDs. Overall, these data define the nature of LD morphology and organelle-organelle contacts during aging and provide insight into LD contact site changes that interconnect biogerontology with mitochondrial function, metabolism, and bioactivity in aged BAT.

11.
12.
bioRxiv ; 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38979162

ABSTRACT

The liver, the largest internal organ and a metabolic hub, undergoes significant declines due to aging, affecting mitochondrial function and increasing the risk of systemic liver diseases. How the mitochondrial three-dimensional (3D) structure changes in the liver across aging, and the biological mechanisms regulating such changes confers remain unclear. In this study, we employed Serial Block Face-Scanning Electron Microscopy (SBF-SEM) to achieve high-resolution 3D reconstructions of murine liver mitochondria to observe diverse phenotypes and structural alterations that occur with age, marked by a reduction in size and complexity. We also show concomitant metabolomic and lipidomic changes in aged samples. Aged human samples reflected altered disease risk. To find potential regulators of this change, we examined the Mitochondrial Contact Site and Cristae Organizing System (MICOS) complex, which plays a crucial role in maintaining mitochondrial architecture. We observe that the MICOS complex is lost during aging, but not Sam50. Sam50 is a component of the sorting and assembly machinery (SAM) complex that acts in tandem with the MICOS complex to modulate cristae morphology. In murine models subjected to a high-fat diet, there is a marked depletion of the mitochondrial protein SAM50. This reduction in Sam50 expression may heighten the susceptibility to liver disease, as our human biobank studies corroborate that Sam50 plays a genetically regulated role in the predisposition to multiple liver diseases. We further show that changes in mitochondrial calcium dysregulation and oxidative stress accompany the disruption of the MICOS complex. Together, we establish that a decrease in mitochondrial complexity and dysregulated metabolism occur with murine liver aging. While these changes are partially be regulated by age-related loss of the MICOS complex, the confluence of a murine high-fat diet can also cause loss of Sam50, which contributes to liver diseases. In summary, our study reveals potential regulators that affect age-related changes in mitochondrial structure and metabolism, which can be targeted in future therapeutic techniques.

14.
bioRxiv ; 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38915603

ABSTRACT

BACKGROUND: Salt sensitivity of blood pressure (SSBP) is an independent risk factor for cardiovascular morbidity and mortality, yet the etiology is poorly understood. We previously found that serum/glucocorticoid-regulated kinase 1 (SGK1) and epoxyeicosatrienoic acids (EETs) regulate epithelial sodium channel (ENaC)-dependent sodium entry into monocyte-derived antigen-presenting cells (APCs) and activation of NADPH oxidase, leading to the formation of isolevuglandins (IsoLGs) in SSBP. Whereas aldosterone via the mineralocorticoid receptor (MR) activates SGK1 leading to hypertension, our past findings indicate that levels of plasma aldosterone do not correlate with SSBP, and there is little to no MR expression in APCs. Thus, we hypothesized that cortisol acting via the glucocorticoid receptor (GR), not the MR in APCs mediates SGK1 actions to induce SSBP. METHODS: We performed cellular indexing of transcriptomes and epitopes by sequencing (CITE-Seq) analysis on peripheral blood mononuclear cells of humans rigorously phenotyped for SSBP using an inpatient salt loading/depletion protocol to determine expression of MR, GR, and SGK1 in immune cells. In additional experiments, we performed bulk transcriptomic analysis on isolated human monocytes following in vitro treatment with high salt from a separate cohort. We then measured urine and plasma cortisol, cortisone, renin, and aldosterone. Subsequently, we measured the association of these hormones with changes in systolic, diastolic, mean arterial pressure and pulse pressure as well as immune cell activation via IsoLG formation. RESULTS: We found that myeloid APCs predominantly express the GR and SGK1 with no expression of the MR. Expression of the GR in APCs increased after salt loading and decreased with salt depletion in salt-sensitive but not salt-resistant people and was associated with increased expression of SGK1. Moreover, we found that plasma and urine cortisol/cortisone but not aldosterone/renin correlated with SSBP and APCs activation via IsoLGs. We also found that cortisol negatively correlates with EETs. CONCLUSION: Our findings suggest that renal cortisol signaling via the GR but not the MR in APCs contributes to SSBP via cortisol. Urine and plasma cortisol may provide an important currently unavailable feasible diagnostic tool for SSBP. Moreover, cortisol-GR-SGK1-ENaC signaling pathway may provide treatment options for SSBP.

15.
Eur Heart J ; 45(34): 3152-3160, 2024 Sep 07.
Article in English | MEDLINE | ID: mdl-38848106

ABSTRACT

BACKGROUND AND AIMS: A cardiovascular disease polygenic risk score (CVD-PRS) can stratify individuals into different categories of cardiovascular risk, but whether the addition of a CVD-PRS to clinical risk scores improves the identification of individuals at increased risk in a real-world clinical setting is unknown. METHODS: The Genetics and the Vascular Health Check Study (GENVASC) was embedded within the UK National Health Service Health Check (NHSHC) programme which invites individuals between 40-74 years of age without known CVD to attend an assessment in a UK general practice where CVD risk factors are measured and a CVD risk score (QRISK2) is calculated. Between 2012-2020, 44,141 individuals (55.7% females, 15.8% non-white) who attended an NHSHC in 147 participating practices across two counties in England were recruited and followed. When 195 individuals (cases) had suffered a major CVD event (CVD death, myocardial infarction or acute coronary syndrome, coronary revascularisation, stroke), 396 propensity-matched controls with a similar risk profile were identified, and a nested case-control genetic study undertaken to see if the addition of a CVD-PRS to QRISK2 in the form of an integrated risk tool (IRT) combined with QRISK2 would have identified more individuals at the time of their NHSHC as at high risk (QRISK2 10-year CVD risk of ≥10%), compared with QRISK2 alone. RESULTS: The distribution of the standardised CVD-PRS was significantly different in cases compared with controls (cases mean score .32; controls, -.18, P = 8.28×10-9). QRISK2 identified 61.5% (95% confidence interval [CI]: 54.3%-68.4%) of individuals who subsequently developed a major CVD event as being at high risk at their NHSHC, while the combination of QRISK2 and IRT identified 68.7% (95% CI: 61.7%-75.2%), a relative increase of 11.7% (P = 1×10-4). The odds ratio (OR) of being up-classified was 2.41 (95% CI: 1.03-5.64, P = .031) for cases compared with controls. In individuals aged 40-54 years, QRISK2 identified 26.0% (95% CI: 16.5%-37.6%) of those who developed a major CVD event, while the combination of QRISK2 and IRT identified 38.4% (95% CI: 27.2%-50.5%), indicating a stronger relative increase of 47.7% in the younger age group (P = .001). The combination of QRISK2 and IRT increased the proportion of additional cases identified similarly in women as in men, and in non-white ethnicities compared with white ethnicity. The findings were similar when the CVD-PRS was added to the atherosclerotic cardiovascular disease pooled cohort equations (ASCVD-PCE) or SCORE2 clinical scores. CONCLUSIONS: In a clinical setting, the addition of genetic information to clinical risk assessment significantly improved the identification of individuals who went on to have a major CVD event as being at high risk, especially among younger individuals. The findings provide important real-world evidence of the potential value of implementing a CVD-PRS into health systems.


Subject(s)
Cardiovascular Diseases , Humans , Middle Aged , Female , Male , Cardiovascular Diseases/genetics , Cardiovascular Diseases/epidemiology , Risk Assessment/methods , Aged , Adult , Case-Control Studies , Risk Factors , Heart Disease Risk Factors , Multifactorial Inheritance/genetics , Genetic Risk Score
16.
bioRxiv ; 2024 May 21.
Article in English | MEDLINE | ID: mdl-38826465

ABSTRACT

The physical characteristics of brown adipose tissue (BAT) are defined by the presence of multilocular lipid droplets (LD) within the brown adipocytes and a high abundance of iron-containing mitochondria, which give it its characteristic color. Normal mitochondrial function is, in part, regulated by organelle-to-organelle contacts. Particularly, the contact sites that mediate mitochondria-LD interactions are thought to have various physiological roles, such as the synthesis and metabolism of lipids. Aging is associated with mitochondrial dysfunction, and previous studies show that there are changes in mitochondrial structure and proteins that modulate organelle contact sites. However, how mitochondria-LD interactions change with aging has yet to be fully clarified. Therefore, we sought to define age-related changes in LD morphology and mitochondria-lipid interactions in BAT. We examined the three-dimensional morphology of mitochondria and LDs in young (3-month) and aged (2-year) murine BAT using serial block face-scanning electron microscopy and the Amira program for segmentation, analysis, and quantification. Analysis showed reductions in LD volume, area, and perimeter in aged samples compared to young samples. Additionally, we observed changes in LD appearance and type in aged samples compared to young samples. Notably, we found differences in mitochondrial interactions with LDs, which could implicate that these contacts may be important for energetics in aging. Upon further investigation, we also found changes in mitochondrial and cristae structure for mitochondria interacting with LD lipids. Overall, these data define the nature of LD morphology and organelle-organelle contacts during aging and provide insight into LD contact site changes that interconnect biogerontology and mitochondrial functionality, metabolism, and bioactivity in aged BAT.

17.
bioRxiv ; 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38915644

ABSTRACT

The kidney filters nutrient waste and bodily fluids from the bloodstream, in addition to secondary functions of metabolism and hormone secretion, requiring an astonishing amount of energy to maintain its functions. In kidney cells, mitochondria produce adenosine triphosphate (ATP) and help maintain kidney function. Due to aging, the efficiency of kidney functions begins to decrease. Dysfunction in mitochondria and cristae, the inner folds of mitochondria, is a hallmark of aging. Therefore, age-related kidney function decline could be due to changes in mitochondrial ultrastructure, increased reactive oxygen species (ROS), and subsequent alterations in metabolism and lipid composition. We sought to understand if there is altered mitochondrial ultrastructure, as marked by 3D morphological changes, across time in tubular kidney cells. Serial block facing-scanning electron microscope (SBF-SEM) and manual segmentation using the Amira software were used to visualize murine kidney samples during the aging process at 3 months (young) and 2 years (old). We found that 2-year mitochondria are more fragmented, compared to the 3-month, with many uniquely shaped mitochondria observed across aging, concomitant with shifts in ROS, metabolomics, and lipid homeostasis. Furthermore, we show that the mitochondrial contact site and cristae organizing system (MICOS) complex is impaired in the kidney due to aging. Disruption of the MICOS complex shows altered mitochondrial calcium uptake and calcium retention capacity, as well as generation of oxidative stress. We found significant, detrimental structural changes to aged kidney tubule mitochondria suggesting a potential mechanism underlying why kidney diseases occur more readily with age. We hypothesize that disruption in the MICOS complex further exacerbates mitochondrial dysfunction, creating a vicious cycle of mitochondrial degradation and oxidative stress, thus impacting kidney health.

18.
STAR Protoc ; 5(2): 102997, 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38748884

ABSTRACT

It is well-understood that the science, technology, engineering, and mathematics (STEM) fields have unique challenges that discourage recruiting and retaining underrepresented minorities. Research programs aimed at undergraduates have arisen as a critical mechanism for fostering innovation and addressing the challenges faced by underrepresented minorities. Here, we review various undergraduate research programs designed to provide exposure to undergraduates, with a focus on underrepresented minorities in STEM disciplines. We provide insight into selected programs' objectives, key features, potential limitations, and outcomes. We also offer recommendations for future improvements of each research program, particularly in the context of mentorship. These programs range from broad-reaching initiatives (e.g., Leadership Alliance) to more specific programs targeting underrepresented students. By offering a nuanced understanding of each program's structure, we seek to provide a brief overview of the landscape of diversity-focused STEM initiatives and a guide on how to run a research program effectively.


Subject(s)
Mathematics , Minority Groups , Science , Students , Technology , Humans , Minority Groups/education , Technology/education , Science/education , Mathematics/education , Research/education , Universities , Engineering/education
19.
Breast Cancer Res ; 26(1): 85, 2024 May 28.
Article in English | MEDLINE | ID: mdl-38807211

ABSTRACT

BACKGROUND: Abbreviated breast MRI (FAST MRI) is being introduced into clinical practice to screen women with mammographically dense breasts or with a personal history of breast cancer. This study aimed to optimise diagnostic accuracy through the adaptation of interpretation-training. METHODS: A FAST MRI interpretation-training programme (short presentations and guided hands-on workstation teaching) was adapted to provide additional training during the assessment task (interpretation of an enriched dataset of 125 FAST MRI scans) by giving readers feedback about the true outcome of each scan immediately after each scan was interpreted (formative assessment). Reader interaction with the FAST MRI scans used developed software (RiViewer) that recorded reader opinions and reading times for each scan. The training programme was additionally adapted for remote e-learning delivery. STUDY DESIGN: Prospective, blinded interpretation of an enriched dataset by multiple readers. RESULTS: 43 mammogram readers completed the training, 22 who interpreted breast MRI in their clinical role (Group 1) and 21 who did not (Group 2). Overall sensitivity was 83% (95%CI 81-84%; 1994/2408), specificity 94% (95%CI 93-94%; 7806/8338), readers' agreement with the true outcome kappa = 0.75 (95%CI 0.74-0.77) and diagnostic odds ratio = 70.67 (95%CI 61.59-81.09). Group 1 readers showed similar sensitivity (84%) to Group 2 (82% p = 0.14), but slightly higher specificity (94% v. 93%, p = 0.001). Concordance with the ground truth increased significantly with the number of FAST MRI scans read through the formative assessment task (p = 0.002) but by differing amounts depending on whether or not a reader had previously attended FAST MRI training (interaction p = 0.02). Concordance with the ground truth was significantly associated with reading batch size (p = 0.02), tending to worsen when more than 50 scans were read per batch. Group 1 took a median of 56 seconds (range 8-47,466) to interpret each FAST MRI scan compared with 78 (14-22,830, p < 0.0001) for Group 2. CONCLUSIONS: Provision of immediate feedback to mammogram readers during the assessment test set reading task increased specificity for FAST MRI interpretation and achieved high diagnostic accuracy. Optimal reading-batch size for FAST MRI was 50 reads per batch. Trial registration (25/09/2019): ISRCTN16624917.


Subject(s)
Breast Neoplasms , Learning Curve , Magnetic Resonance Imaging , Mammography , Humans , Female , Breast Neoplasms/diagnostic imaging , Breast Neoplasms/diagnosis , Magnetic Resonance Imaging/methods , Mammography/methods , Middle Aged , Early Detection of Cancer/methods , Prospective Studies , Aged , Sensitivity and Specificity , Image Interpretation, Computer-Assisted/methods , Breast/diagnostic imaging , Breast/pathology
20.
bioRxiv ; 2024 May 15.
Article in English | MEDLINE | ID: mdl-38798364

ABSTRACT

Alzheimer's Disease (AD) is a global health issue, affecting over 6 million in the United States, with that number expected to increase as the aging population grows. As a neurodegenerative disorder that affects memory and cognitive functions, it is well established that AD is associated with cardiovascular risk factors beyond only cerebral decline. However, the study of cerebrovascular techniques for AD is still evolving. Here, we provide reproducible methods to measure impedance-based pulse wave velocity (PWV), a marker of arterial stiffness, in the systemic vascular (aortic PWV) and in the cerebral vascular (cerebral PWV) systems. Using aortic impedance and this relatively novel technique of cerebral impedance to comprehensively describe the systemic vascular and the cerebral vascular systems, we examined the sex-dependent differences in 5x transgenic mice (5XFAD) with AD under normal and high-fat diet, and in wild-type mice under a normal diet. Additionally, we validated our method for measuring cerebrovascular impedance in a model of induced stress in 5XFAD. Together, our results show that sex and diet differences in wildtype and 5XFAD mice account for very minimal differences in cerebral impedance. Interestingly, 5XFAD, and not wildtype, male mice on a chow diet show higher cerebral impedance, suggesting pathological differences. Opposingly, when we subjected 5XFAD mice to stress, we found that females showed elevated cerebral impedance. Using this validated method of measuring impedance-based aortic and cerebral PWV, future research may explore the effects of modifying factors including age, chronic diet, and acute stress, which may mediate cardiovascular risk in AD.

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