Conectar
by Namhee Kim, Bo Gyeong Lee
PurposeSleep quality is a multidimensional construct encompassing the effectiveness and restorativeness of sleep. The pre-sleep arousal scale is a widely used instrument for evaluating aspects of arousal that are closely related to sleep quality. This study aimed to evaluate the psychometric properties of the Korean version of the pre-sleep arousal scale (K-PSAS).
MethodsWe performed a secondary analysis of cross-sectional data from 286 adults aged 19–70 years who used electronic cigarettes or heated tobacco products. The original PSAS was translated into Korean, with content validity assessed by experts. Construct validity was evaluated via exploratory factor analysis, and concurrent validity was assessed by correlating the K-PSAS with the Insomnia Severity Index, Pittsburgh Sleep Quality Index, and Hospital Anxiety and Depression Scale. Reliability was examined using Cronbach’s α, and split-half reliability coefficient.
ResultsBoth the item-level content validity index for all items and the scale-level content validity index average for the K-PSAS-16 were 1.0. After removing the survey item on “being mentally alert and active at bedtime” (item 13) due to low factor loading, the K-PSAS-15 demonstrated a two-factor structure, with somatic and cognitive arousal factors explaining 42.36% and 10.19% of the variance, respectively. A significant positive correlation was observed between the two factors (ρ = 0.61, p Conclusion
The K-PSAS-15, which excludes one poorly performing item from the original scale, is a reliable and valid tool for assessing pre-sleep arousal.
In Bangladesh, evidence on the long-term trajectory of adolescents' sexual and reproductive health (SRH) remains limited, largely due to the lack of longitudinal data to assess the changes over time. To address this gap, the Advancing Sexual and Reproductive Health and Rights (AdSEARCH) project of International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b) set up an adolescent cohort study aimed at documenting changes in SRH knowledge, attitudes and practices, and identifying the factors affecting these changes. This article presents the baseline sociodemographic and SRH characteristics of this cohort as a pathway for future analyses.
This cohort study included 2713 adolescents from the Baliakandi Health and Demographic Surveillance System run by icddr,b. The cohort covered three age groups from girls and boys, giving a total of five cohorts: girls aged 12, 14 and 16 years; and boys aged 14 and 16 years. A total of seven rounds of data had been collected at 4-month intervals over 2-years follow-up period.
The majority of adolescents were attending school (90%), and school dropouts were higher among boys. Around 17% of the respondents were involved in income-generating activities, which were mostly boys. Among girls, the mean age of menarche was 12.2 years. Overall, 6% of adolescents had major depressive disorder, with prevalence increasing with age. Gender differences were evident regarding knowledge about conception and contraception. Egalitarian attitudes towards social norms and gender roles were found higher among girls (52%) compared to boys (11%). The majority of adolescents reported experiencing social/verbal bullying (43%), followed by physical violence (38%) and cyberbullying (4%).
This article presents the baseline findings only. A series of papers is in the pipeline for submission to different peer-reviewed journals. The findings from this study will be used to support data-driven policy formulation for future adolescent health programmes.
Maternal respiratory syncytial virus (RSV) vaccination has been introduced to protect infants from severe respiratory infections. However, its uptake and impact on perinatal outcomes are unknown in the UK.
To evaluate uptake of RSV vaccine during pregnancy in a UK population.
This cross-sectional study was conducted at a tertiary maternity hospital in London. The participants included pregnant women who delivered between 1 September and 17 December 2024 (n=1157). For the analysis of vaccine uptake, the cohort included women eligible for vaccination who delivered beyond 28 weeks’ gestation and were at 36 weeks or less on 1 September 2024 (n=911). The main outcome measures were RSV vaccine uptake and its association with sociodemographic factors, perinatal outcomes including preterm birth (PTB), hypertensive disorders of pregnancy and stillbirth.
Of 911 eligible women, 19% (n=173) received the RSV vaccine during pregnancy. Uptake increased significantly from 4% in September to 32% in December (p
RSV vaccine uptake shows significant increases over time, with disparities in uptake by ethnicity and socioeconomic status. Further research is needed to increase vaccination rates, particularly in disadvantaged groups, and evaluate perinatal outcomes.
Nurses play vital roles in healthcare systems, especially in competitive environments that must meet diverse stakeholder expectations, improve quality and foster innovation. However, these efforts are often challenged by workforce issues such as nurse turnover intention, which is a critical concern requiring effective leadership and management. Despotic leadership is harmful and may lead to negative nurse behaviours, including intentions to leave their positions.
This study explored the correlations and differences in the clinical nurse managers' despotic leadership and nurse turnover intention based on the sample characteristics as perceived by registered nurses (RNs) working in the selected hospitals in Jordan.
This study employed a quantitative cross-sectional correlational comparative design to measure the relationships and differences between the perceived despotic leadership of nurse managers and nurse turnover intention. In 2024, a paper-format survey was distributed to nurses working in various hospitals. Five governmental and private hospitals in Jordan were purposively chosen to recruit 301 nurses using non-probability convenience snowball sampling techniques. Sample size was collected using G* power, and data were collected using a highly psychometric instrument of the Toxic Leadership Behaviours of Nurse Managers Scale (The ToxBH-NM Scale) and the Turnover Intention Scale (TIS-6 Items).
The overall score for clinical nurse managers' despotic indicated a moderate level of despotic leadership among nurse managers. Among the nurses surveyed, 53 (17.60%) expressed an intention to stay in their positions, while 248 (82.30%) indicated they intended to leave those positions. There was a statistically significant weak positive correlation between the total score of perceived clinical nurse managers' despotic leadership and the total score of perceived nurse turnover intention (r = 0.215, p = 0.01). This correlation suggests a small effect size (Cohen's guidelines: small = 0.10, medium = 0.30, large = 0.50), indicating that while the relationship was statistically significant, the practical impact was at a small level. No significant differences were found in the perceived despotic leadership of nurse managers or nurse turnover intention.
The findings highlighted the critical roles of leaders, policymakers and organisations in reducing the perceived despotic leadership of nurse managers. These roles are crucial in decreasing nurses' intentions to leave their jobs.
Accurately identifying despotic management behaviours is crucial. To improve nurse retention, healthcare organisations should implement evidence-based interventions targeting job satisfaction, workload management and ongoing professional development.
This study did not include patient or public involvement in its design, conduct or reporting.
Predicting medical/surgical nurses' delivery of patient pressure injury prevention education within 24 h of hospitalisation.
A cross-sectional sub-study drawn from a larger multisite randomised controlled trial.
A consecutive sub-sample of 300 randomly assigned control group participants was recruited from 20 medical and surgical wards at two major hospitals (July 2020 to August 2023) in Queensland, Australia. Semi-structured observations and chart audit data were collected, including patient education, demographic and clinical data. Binary logistic regression identified hospital site, clinical and patient predictors contributing to pressure injury prevention education delivery by nurses.
Seventeen (5.7%) participants received pressure injury prevention education within the first 24 h of admission. Body mass index was an independent predictor, increasing the odds of nurses delivering patient education.
Few episodes of pressure injury prevention education were observed in this study. As a patient's body mass index rises, they are more likely to receive preventative education from nurses soon after admission.
Our findings underscore the need for standardised inclusive protocols and ongoing nurse training to assess and address education needs beyond single risk factors like body mass index. Further research should explore other factors influencing patient education delivery in hospitals.
This study adhered to STROBE guidelines. Dr. Brett Dyer, statistician, is part of the author team.
No patient or public contribution.
Many frontline essential working mothers returned to work outside of the home after maternity leave during the COVID-19 pandemic. The purpose of this study is to describe the changes in breastfeeding relationships.
A longitudinal descriptive qualitative design was used.
Four open-ended questions were asked to explore breastfeeding experiences at home, mothers' thoughts and feelings during direct breastfeeding, strategies to solve their breastfeeding problems, and workplace breastfeeding support. Data were collected by an online survey at 1, 3, 5 and 6 months between June 2022 and August 2023. Data were analysed using inductive content analysis from 21 mothers in the United States who were directly breastfeeding at least once a day for the first 6 months. The trustworthiness of study results involved coding by consensus, peer debriefing, and maintenance of an audit trial.
The core construct, “Changes in Breastfeeding Relationships When Frontline Essential Working Mothers Return to Work Outside of the Home” explained mothers' experience in four domains: (1) Breastfeeding changes, (2) Changes in sleep arrangements, (3) Social support to continue breastfeeding, and (4) Physical and emotional distress of mothers and infants.
Unrestricted direct breastfeeding upon reunion through the night along with co-sleeping was the strategy mothers used to restore breastfeeding relationships with their infants and continue direct breastfeeding. Scheduled feeding and solitary sleep resulted in less direct breastfeeding, had negative consequences such as low milk supply, slow infant weight gain, and maternal distress.
Even though frontline essential working mothers persevered with the complexities of their work during the COVID-19 pandemic, findings highlight challenges mothers faced with their breastfeeding experience. Nurses need to discuss with mothers expected challenges of less frequent direct breastfeeding along with emotional tolls while being separated from their infant and strategies to develop sustainable breastfeeding relationships and continuation of direct breastfeeding.
None.
To explore the social context of violence for hospital-based and community nurses from different ethnic groups, the types of violence experienced or witnessed both in and outside the workplace, and its impact on mental and physical health.
Cross-sectional, qualitative study using semi-structured interviews.
Semi-structured interviews were conducted online with 12 hospital-based and community nurses recruited from London, England, between May and August 2021. Data were analysed using reflexive thematic analysis.
The sample comprised seven hospital nurses and five community nurses. Four themes were identified: (i) the social context in which nurses from different ethnic groups are exposed to community violence; (ii) types of workplace violence experienced or witnessed by hospital-based and community nurses from different ethnic groups; (iii) perceptions of the factors contributing to workplace violence; (iv) impacts of violence on mental and physical health outcomes. Using the social ecological framework and sociological theory of stress, these findings informed a conceptual stress process model of violence exposure for nurses.
Nurses from different ethnic groups are exposed to violence both in and outside the workplace which negatively affects their mental and physical health. Effective violence prevention requires a multi-factorial approach that addresses the social and institutional factors contributing to violence, shifting the focus from individual measures to systemic organisational changes.
The NHS workforce is currently more diverse than ever, and healthcare leaders must improve access to mental health and well-being resources for staff affected by workplace violence, particularly for those who hold multiple social identities at the intersection of ethnicity, gender and age. Prioritising this support is essential not only to safeguard against negative health outcomes but also to improve the recruitment and retention of healthcare professionals.
No patient or public contribution.
Chronic caregiving stress accelerates biological aging, reflecting disease risk and mortality; however, the underlying mechanisms are poorly understood. Epigenetic clocks, which can be estimated from levels of DNA methylation in a subset of cytosine-phosphate-guanine loci in the genome, have been proposed as a promising biological age estimator. The objectives of this scoping review are to systematically scope the literature on the effects of stress on biological ageing measured by epigenetic clocks in family caregivers of patients diagnosed with cancer.
This review will be conducted following Joanna Briggs Institute methodology based on Arksey and O’Malley’s and Levac et al’s framework and reported using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines for scoping reviews. Studies will be included if (1) the studies focus on unpaid family caregivers of patients diagnosed with cancer; (2) caregivers are adults (≥18 years of age) and (3) the study measured epigenetic clocks. The search will encompass literature and peer-reviewed literature in PubMed/MEDLINE (National Library of Medicine), Embase (Elsevier), Cochrane CENTRAL (Wiley & Sons), Web of Science: Core Collection (Clarivate Analytics), CINAHL (EBSCOhost) and PsycInfo (American Psychological Association).
Since the scoping review methodology focuses on published literature, this study does not require ethical approval. We will publish our findings in a peer-reviewed journal and plan to disseminate our work in conferences and scientific meetings.
Open Science Framework (https://doi.org/10.17605/OSF.IO/KW7RT).
Incretin-based drugs, including glucagon-like peptide-1 (GLP-1) receptor agonists (RAs) and dual glucose-dependent insulinotropic polypeptide (GIP)/GLP-1 RAs, are increasingly used in the management of type 2 diabetes mellitus and obesity. While these agents have shown cardiovascular benefits, their effects on both cardiovascular outcomes and cardiac structure and function remain uncertain—particularly in patients with and without a history of heart failure (HF).
We will conduct a systematic review and search major medical databases (Cochrane Central Register of Controlled Trials (CENTRAL), Medical Literature Analysis and Retrieval System Online (MEDLINE), Excerpta Medica Database (EMBASE), Latin American and Caribbean Health Sciences Literature (LILACS), Science Citation Index Expanded (SCI-EXPANDED) and Conference Proceedings Citation Index-Science (CPCI-S)), as well as clinical trial registries from their inception and onwards to identify relevant randomised trials. The literature search is scheduled for July 2025. Two review authors will independently extract data and assess risk of bias. We will include randomised controlled trials assessing the effects of cagrilintide/semaglutide, liraglutide, semaglutide and tirzepatide in patients with and without a history of HF. The primary outcome will be cardiovascular mortality. Secondary outcomes will include HF hospitalisation, myocardial infarction, stroke, heart rate, systolic blood pressure, N-terminal pro B-type natriuretic peptide, left ventricular ejection fraction, left ventricular end-diastolic volume and left ventricular end-systolic volume. Data will be synthesised by aggregate data meta-analyses and trial sequential analysis. Risk of bias will be assessed with the Cochrane Risk of Bias tool, version 2, and the certainty of the evidence will be assessed by Grading of Recommendations, Assessment, Development and Evaluations (GRADE).
As this study is a systematic review based on secondary analysis of published data, ethical approval is not required. Findings will be published in international peer-reviewed scientific journals.
CRD420251003374.
Mycobacteroides abscessus (MABS) is within the non-tuberculous mycobacteria family. It inhabits soil and water, exhibits multi-antibiotic resistance and causes opportunistic lung infections, which may progress to symptomatic MABS-pulmonary disease (MABS-PD) associated with substantial morbidity, increased healthcare utilisation, impaired quality of life and increased mortality. Treatment regimens for MABS-PD are highly variable, not evidence-based and involve complex, expensive drug combinations administered for prolonged periods (>12 months) with frequent adverse effects and treatment failure. There is an urgent need for safe, efficacious and cost-effective MABS-PD therapy. Here, we describe the Master Protocol for the Finding the Optimal Regimen for Mycobacteroides abscessus Treatment (FORMaT) trial. FORMaT aims to determine the most effective and best tolerated treatment for MABS-PD as defined by MABS clearance from respiratory samples with good treatment tolerance.
FORMaT is an international multicentre, adaptive platform trial evaluating treatment combinations for MABS-PD. Participants are randomised multiple times during the trial, with assessment of the primary outcome of clearance of MABS infection with good treatment tolerance. Initially, therapies recommended in international consensus guidelines are being tested. Data obtained will eliminate therapies lacking efficacy or causing unacceptable toxicity. Novel treatments can then be added and tested against previously determined optimal approaches, leading in an iterative fashion to improved microbiological clearance and health outcomes. In parallel, an Observational cohort and several integrated and discovery studies are embedded in FORMaT to identify biomarkers of MABS-PD and MABS clearance, clinical and radiographic treatment response, drug pharmacokinetics and Mycobacteroides genomics and resistome.
The FORMaT Master Protocol and related documents are approved by regulatory authorities in each participating jurisdiction and/or site. Results will be published in peer-reviewed journals and presented at scientific meetings. De-identified, aggregated data will be shared on an approved online platform.
NCT04310930, ANZCTR12618001831279, 2020-000050-10,
(1) Analyse in depth an exemplar safety-critical task required of newly qualified doctors (prescribing insulin) and (2) Provide transferable insights into how undergraduate education could better educate medical students to meet the demands of practice when they become postgraduate trainees.
Document analysis of doctors’ reported experiences of insulin prescribing, an everyday task that has an emergent logic of practice and harms not just patients but (psychologically) new doctors. Application of third-generation (social emergence) complexity theory to explore why practice can be ‘mutually unsafe’.
A system of care comprising all five Northern Irish (UK) Health and Social Care Trusts, which together provide healthcare to a population of nearly two million people.
68 postgraduate year 1 and year 2 trainees (PGY1/2s), mainly PGY1s.
Thick description of new doctors’ contexts of action, reasons for acting and specific actions. We present this as a narrative compiling all 68 stories, 13 detailed exemplar stories and a diagram summarising how multiple factors interacted to make practice complex.
Situations that required PGY1/2s to act had interacting layers of complexity: (1) disease trajectories; (2) social dynamics between stakeholders and (3) contextual influences on stakeholders’ interactions. Out-of-hours working and unsuitable wards intensified troublesome contextual influences. All three individually complex layers ‘crystallised’ briefly to create ‘moments of action’. At best, PGY1/2s responded proactively, ‘stretched time’ and checked the results of their actions. At worst, PGY1/2s ‘played safe’ in unsafe ways (eg, took no action), acted on unsafe advice or defaulted to actions protecting them from criticism. Informal, pervasive rules emerged from, and perpetuated, unsafe practice.
New doctors’ work includes acting on indeterminate, emergent situations whose complexity defies rules that are determinate enough to be taught off the job. If new doctors are to perform capably in moments of action, medical students need ample, supervised, situated experience of what it is like to take responsibility in such moments.
by Changseok Lee, Liam Redden, Vivian Eng, Brennan Eadie
PurposeTo investigate the luminance capacity and achievable threshold levels of commercially employed virtual reality (VR) devices for visual field testing.
MethodsThis two-part study included (1) a literature review of VR headsets used for perimetry with luminance data extracted from technical specifications in publications and manufacturers; and (2) empirical evaluation of three most employed VR headsets in the literature using a custom virtual testing environment.
ResultsThree most employed VR devices for visual field testing were Pico Neo, Oculus Quest, and HTC Vive. The maximum reported luminance was 250 cd/m2 for the HTC Vive Pro. Information on luminance measurement was not consistently available, reporting only handheld luminance meters. Empirical measurements show that handheld luminance meters significantly overestimate luminance compared to standard spectroradiometers. Measured luminance varies significantly across aperture size and decreases for peripheral stimuli up to 30 degrees peripherally. Assuming conventional background of 10 cd/m2, the best performance with lowest possible thresholding was with HTC Vive at 16dB, corresponding to luminance of 80 cd/m2 centrally. Oculus Quest 2 and Pico Neo 3 had minimum threshold of 20dB.
ConclusionCommercially available VR devices do not meet luminance requirements or threshold sensitivities for visual field testing. Current VR technology is not designed—nor has the capacity—to threshold at mid-to-low dB ranges, which limits accuracy in diagnosing and monitoring defects seen in glaucoma. Translational Relevance: This study highlights the technical limitations of current commercially available VR devices for visual field testing and significant variables in evaluating luminance performance in these devices.
Despite low sensitivity and implementation challenges, the tuberculin skin test (TST) remains the standard-of-care tuberculosis (TB) infection test in Mexico. Interferon gamma release assays (IGRA) may overcome TST-related challenges. Within the confines of the local programmatic setting, this cross-sectional study evaluated the prevalence of TB infection (TBI) and concordance of TST and IGRA in three high-risk populations in Mexicali, Baja California, Mexico.
Household contacts (HHC) of individuals with TB, people who use drugs (PWUD), people deprived of liberty (PDL) and prison employees underwent evaluation for TBI using TST and QIAreach, a novel IGRA. Prevalence of infection, concordance of test results and reactivity trends of time-to-results (TTR) by TST-induration size were assessed.
In total, 214 of 411 (52.07%) people who had TST and 269 of 460 (58.48%) people who had IGRA tested positive for TBI. Frequency of infection varied across risk groups (HHC 29 (29.6%); PWUD 67 (70.53%); PDL 111 (56.06%) and prison employees 7 (35.0%), p20 mm, p=0.05).
All risk groups had a high frequency of TBI, necessitating locally tailored guidelines for screening, treatment and management of TBI to optimise care for vulnerable populations.
Emicizumab is the first bispecific antibody approved for prophylaxis in people with haemophilia A with or without factor VIII inhibitors. Aggregate distributional cost-effectiveness analysis assesses health equity impacts by evaluating how health effects and costs from funding an intervention are distributed among population subgroups. The objective was to evaluate how funding emicizumab for people with severe haemophilia A (PwSHA) impacts population health and health disparities in the USA.
Population-level model of PwSHA from the perspective of the US healthcare system, using published sources and considering a lifetime time horizon.
Emicizumab versus other haemophilia A prophylaxis treatments.
Quality-adjusted life-years (QALYs) gained and change in Atkinson index of inequality in quality-adjusted life expectancy.
When an estimated 6512 PwSHA in the USA were treated with emicizumab, the US healthcare system would save US$160 billion over those individuals’ lifetimes. If these cost savings fund additional healthcare interventions in the overall population, funding emicizumab would improve overall US population health (1 068 903 QALYs gained, using a threshold of US$150 000/QALY) and reduce existing overall US inequities (–0.01% on the Atkinson index).
In all scenarios tested for sensitivity, increased emicizumab and prophylaxis utilisation led to further reductions in health disparities and greater increases in population health. Results were robust to deterministic variations in the allocation of cost savings due to emicizumab use.
Funding emicizumab treatments for PwSHA improves overall population health and reduces overall health inequities in the USA. Cost savings from the use of emicizumab free up important resources that can be leveraged to support other healthcare interventions, but decisions on how these funds are used have large consequences for equity.
This study uses nationally representative survey data from the USA to estimate the relationship between a history of heart attack or stroke with the prevalence of mental health symptoms.
Cross-sectional.
Data from the 2019 and the 2018 National Health Interview Survey (NHIS) sample adult interview.
30 872 adults from the 2019 NHIS and 24 593 adults from the 2018 NHIS were analysed separately; a history of heart attack or stroke was determined based on participants’ recollection of previous communications with health professionals.
Poisson log-linear regressions with robust SEs were employed to estimate the relative prevalence of mental health symptoms associated with a history of heart attack or stroke. Mental health outcomes included moderate-to-severe depression symptoms according to the Patient Health Questionnaire, moderate-to-severe anxiety symptoms according to the General Anxiety Disorder scale and serious psychological distress according to the Kessler Psychological Distress scale.
The prevalence of moderate-to-severe symptoms of depression, anxiety and serious psychological distress was more than two times as high among individuals with a history of heart attack or stroke compared with those without such a history. After adjusting for potentially confounding socio-demographic and health variables, survivors of heart attack were 33% and 40% more likely and survivors of stroke were 59% and 52% more likely to experience depression and anxiety symptoms, compared with adults without these conditions. Additionally, survivors of stroke were 76% more likely to have serious psychological distress than those without a stroke history.
Findings from this study highlight the increased mental health problems experienced by heart attack or stroke survivors relative to adults without these conditions. They underscore the importance of addressing mental health concerns among adults who have experienced a heart attack or stroke.
To canvas the contemporary contextual forces within the Australian residential aged care sector and argue for new research and innovation. There is a pressing need to provide systematised, high-quality and person-centred care to our ageing populations, especially for those who rely on residential care. This paper advances a warrant for establishing a new systematic framework for assessment and management that serves as a foundation for effective person-centred care delivery.
Position paper.
This paper promulgates the current dialogue among key stakeholders of quality residential aged care in Australia, including clinicians, regulatory agencies, researchers and consumers. A desktop review gathered relevant literature spanning research, standards and guidelines regarding current and future challenges in aged care in Australia.
This position paper explores the issues of improving the quality and safety of residential aged care in Australia, including the lingering impact of COVID-19 and incoming reforms. It calls for nurse-led research and innovation to deliver tools to address these challenges.
The paper proposes an appropriate holistic, evidence-based nursing framework to optimise the quality and safety of residential aged care in Australia.
This study did not include patient or public involvement in its design, conduct, or reporting.
by Natalia Surzenko, Ashley Dominique, Taleen Hanania, Melville Osborne, Bassem F. El-Khodor
Polyamines (PAs), including spermidine, spermine and their precursor, putrescine, are ubiquitous molecules that are vital for a variety of physiological processes. Recently, PAs gained research attention because of their roles in promoting longevity and preventing age-related diseases. Circulating and tissue levels of PAs appear to decline with age, while higher intake of PAs in humans is correlated with better health during aging. Many foods, including plants and offal (organ meats), are good sources of dietary PAs, but are consumed much less in regions with prevailing Western diets. Elevating the circulating levels of PAs through dietary supplementation with PA-rich plant extracts or foods, on the other hand, has proven to be challenging, most likely due to their low bioavailability. In this study, we evaluated the effectiveness of nutritional supplements derived from bovine glandular tissues and/or plant material in elevating blood and tissue levels of spermidine, spermine and putrescine in adult rats. We detected appreciable amounts of PAs in the following materials: 1) spermidine-rich supplement (SRS), containing wheat germ, 2) a cytosolic fraction extract of bovine thymus gland (Thymus Cytosolic Fraction – TCF) and 3) a nuclear fraction extract of bovine thymus gland (Thymus Nuclear Fraction – TNF). We showed that all three PA-containing supplements also contain liposomes, with TNF displaying the largest amounts of liposomal PAs, as well as RNAs, among the tested supplements. We demonstrated that oral administration of SRS, TCF and TNF induce rapid changes in blood PA concentrations. Finally, we showed that TNF supplement is superior to SRS and TCF in elevating the levels of spermidine in the blood, liver and heart following a 28-day supplementation period. Considering the importance of PAs in prevention of age-related disease, supplementation with TNF could be a plausible approach towards the maintenance of proper cellular PA homeostasis during aging.by Dong Min Jung, Yong Jae Kwon, Yong Wan Cho, Jong Geol Baek, Dong Jae Jang, Yongdo Yun, Seok-Ho Lee, Gahee Son, Hyunjong Yoo, Min Cheol Han, Jin Sung Kim
Volumetric modulated arc therapy (VMAT) for lung cancer involves complex multileaf collimator (MLC) motion, which increases sensitivity to interplay effects with tumour motion. Current dynamic conformal arc methods address this issue but may limit the achievable dose distribution optimisation compared with standard VMAT. This study examined the clinical utility of a VMAT technique with monitor unit limits (VMATliMU) to mimic conformal arc delivery and reduce interplay effects while maintaining plan quality. VMATliMU was implemented by applying monitor unit limitations during VMAT reoptimisation to minimise MLC encroachment into target volumes. Using mesh-type reference computational phantom CT images, treatment plans were generated for a simulated stage I lung cancer case prescribed to 45 Gy in three fractions. VMATliMU, conventional VMAT, VMAT with leaf speed limitations, dynamic conformal arc therapy, and constant dynamic conformal arc therapy were compared. Plans were optimised for multiple isodose line prescriptions (50%, 60%, 70%, 80%, and 90%) to investigate the impact of dose distribution. Evaluation parameters included MLC positional accuracy using area difference ratios, dosimetric indices, gradient metrics, and organ-at-risk doses. VMATliMU prevented MLC encroachment into the internal target volume across 60%–90% isodose lines, showing superior MLC accuracy compared with other methods. At the challenging 50% isodose line, VMATliMU had 4.5 times less intrusion than VMAT with leaf speed limits. VMAT plans had better dosimetric indices than dynamic conformal arc plans. VMATliMU reduced monitor units by 5.1%–19.2% across prescriptions. All plans met the clinical dose constraints, with the aortic arch below tolerance and acceptable lung doses. VMATliMU combines VMAT’s dosimetric benefits with the dynamic conformal arcs’s simplicity, minimising MLC encroachment while maintaining plan quality. Reduced monitor units lower low-dose exposure, treatment time, and interplay effects. VMATliMU is usable in existing planners with monitor unit limits, offering a practical solution for lung stereotactic body radiation therapy.
FreshRSS 