A few days of bed rest or immobilization following injury, disease, or surgery can lead to considerable loss of skeletal muscle mass and strength. It has been speculated that such short, successive ...periods of muscle disuse may be largely responsible for the age-related loss of muscle mass throughout the lifespan.
To assess whether a single intramuscular injection of nandrolone decanoate prior to immobilization can attenuate the loss of muscle mass and strength in vivo in humans.
Thirty healthy (22 ± 1 years) men were subjected to 7 days of one-legged knee immobilization by means of a full leg cast with (NAD, n = 15) or without (CON, n = 15) prior intramuscular nandrolone decanoate injection (200 mg).
Before and immediately after immobilization, quadriceps muscle cross-sectional area (CSA) (by means of single-slice computed tomography (CT) scans of the upper leg) and one-legged knee extension strength (one-repetition maximum 1-RM) were assessed for both legs. Furthermore, muscle biopsies from the immobilized leg were taken before and after immobilization to assess type I and type II muscle fiber cross-sectional area.
Quadriceps muscle CSA decreased during immobilization in both CON and NAD (-6 ± 1% and -6 ± 1%, respectively; main effect of time P<0.01), with no differences between the groups (time × treatment interaction, P = 0.59). Leg muscle strength declined following immobilization (-6 ± 2% in CON and -7 ± 3% in NAD; main effect of time, P<0.05), with no differences between groups (time × treatment interaction, P = 0.55).
This is the first study to report that nandrolone decanoate administration does not preserve skeletal muscle mass and strength during a short period of leg immobilization in vivo in humans.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The majority of studies investigating associations between physical activity and mental health in adolescents have been cross-sectional in design. Potential associations between physical activity and ...mental health may be better examined longitudinally as physical activity levels tend to decrease in adolescence. Few studies have investigated these associations longitudinally in adolescents and none by measuring physical activity objectively.
A total of 158 Dutch adolescents (mean age 13.6 years, 38.6% boys, grades 7 and 9 at baseline) participated in this longitudinal study. Physical activity, depressive symptoms and self-esteem were measured at baseline and at the 1-year follow-up. Physical activity was objectively measured with an ActivPAL3™ accelerometer during one full week. Depressive symptoms were measured with the Center for Epidemiologic Studies Depression Scale (CES-D) and self-esteem was assessed with the Rosenberg Self-Esteem Scale (RSE). Results were analysed using structural equation modelling.
Physical activity levels decreased 15.3% over a 1-year period (p < .001), with significantly (p = .001) greater decreases during grade 7 (-20.7%) than during grade 9 (-5.0%). Overall, depressive symptoms decreased (-12.1%, p < .001) over a 1-year period, while self-esteem did not change significantly (+2.9%, p = .066). Higher levels of depressive symptoms at baseline predicted a greater decline in depressive symptoms (β = -.51, p < .001) and higher levels of self-esteem at baseline predicted a smaller increase in self-esteem (β = -.48, p < .001). The decline in physical activity did not appear to predict any change in depressive symptoms and self-esteem.
The decline in physical activity over a 1-year period during adolescence is not associated with a change in mental health. Further studies in adolescents aiming to investigate whether a change in physical activity is associated with a change in mental health should control for baseline levels of mental health and academic year differences.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Highlights • Mean hospital costs per NSCLC patient are €33,143 for the entire disease duration. • The estimated €33,143 per patient is similar to other international cost estimates. • These results ...can be used to inform health economic models.
The current study examined the associations between active commuting to school, cognitive performance, and academic achievement in Dutch adolescents. In addition, it was explored whether these ...associations were moderated by sex and mediated by depressive symptoms.
Students in grades 7 and 9 (N = 270; mean age 13.4 years; 53% boys) were included. Active commuting to school was measured objectively by an ActivPAL3™ accelerometer. Cognitive performance was measured by the d2 Test of attention (key components of executive functioning) and the Symbol Digit Modalities Test (information-processing speed). Academic achievement was determined by the mean of the school grades obtained in Dutch, mathematics and English. Depressive symptoms were self-reported.
Active commuting to school constituted 28% of the total amount of time spent moving per week. Active commuting to school was not significantly associated with cognitive performance and academic achievement, overall. However, active commuting to school was positively associated with performance on the d2 Test of attention in girls (β = .17, p = .037), but not in boys (β = -.03, p = .660). The associations were not mediated by depressive symptoms.
The associations between active commuting to school and cognitive performance and academic achievement are weak and might be moderated by sex, while the greatest benefits on cognition due to active commuting to school might be with regard to executive functioning. Future studies might make use of experimental designs, because causal relations between active commuting to school and cognitive performance or academic achievement would provide important implications for both education and public health.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
University students sit too much, which is detrimental to their physical and mental health. Academic schedules, including scheduled education time and self-study time, may influence their physical ...activity behaviors.
To investigate (1) the association between scheduled education time and students' physical activity levels during weekdays; (2) the association between self-study time and students' physical activity levels during the weekdays and weekends.
126 (68 Maastricht University (UM); 58 KU Leuven (KUL)) first-year undergraduate students in biomedical sciences (mean ±
age: 19.3 ± 1.0, BMI: 22.0 ± 3.0, 17% men, 83% women) completed a demographics questionnaire and reported their academic activities with a 7-day logbook. Furthermore, their physical activity behavior was measured with the activPAL monitor for 7 days. Linear mixed models were used to examine the associations between university (UM versus KUL), academic activities (scheduled education time and self-study time), and students' activity levels.
During weekdays, each hour of scheduled education time per day was significantly associated with a 1.3 min decrease of moderate to vigorous physical activity (MVPA) per day. Scheduled education time was not significantly associated with the sedentary time, light-intensity physical activity (LPA), and active sedentary behavior ratio. Each hour of self-study per day was significantly associated with 8 min more of sedentary time per day, 6 min less LPA per day, and 1.3 min less MVPA per day. Self-study time was not significantly associated with active sedentary behavior ratio. During the weekend, each hour of self-study time per day was associated with an additional 17.8 min of sedentary time per day and a reduction of 15.2 min of LPA per day. Self-study time was not significantly associated with the time spent doing MVPA and active sedentary behavior ratio.
It could be more effective to change students' physical activity behaviors during self-study than during scheduled education time. Therefore, offering a study environment that reduces sedentary behavior and promotes light-intensity physical activity, is crucial.
Disease recurrence is the main cause of mortality after resection of pancreatic ductal adenocarcinoma (PDAC). In 20-30% of resected patients, isolated local PDAC recurrence occurs. Retrospective ...studies have suggested that stereotactic body radiation therapy (SBRT) might lead to improved local control in these patients, potentially having a beneficial effect on both survival and quality of life. The "nationwide randomized controlled trial on additional treatment for isolated local pancreatic cancer recurrence using stereotactic body radiation therapy" (ARCADE) will investigate the value of SBRT in addition to standard of care in patients with isolated local PDAC recurrence compared to standard of care alone, regarding both survival and quality of life outcomes.
The ARCADE trial is nested within a prospective cohort (Dutch Pancreatic Cancer Project; PACAP) according to the 'Trials within Cohorts' design. All PACAP participants with isolated local PDAC recurrence after primary resection who provided informed consent for being randomized in future studies are eligible. Patients will be randomized for local therapy (5 fractions of 8 Gy SBRT) in addition to standard of care or standard of care alone. In total, 174 patients will be included. The main study endpoint is survival after recurrence. The most important secondary endpoint is quality of life.
It is hypothesized that additional SBRT, compared to standard of care alone, improves survival and quality of life in patients with isolated local recurrence after PDAC resection.
ClinicalTrials.gov registration NCT04881487 . Registered on May 11, 2021.
To evaluate prostate intrafraction motion using MRI during the full course of online adaptive MR-Linac radiotherapy (RT) fractions, in preparation of MR-guided extremely hypofractionated RT.
Five low ...and intermediate risk prostate cancer patients were treated with 20 × 3.1 Gy fractions on a 1.5T MR-Linac. Each fraction, initial MRI (Pre) scans were obtained at the start of every treatment session. Pre-treatment planning MRI contours were propagated and adapted to this Pre scan after which plan re-optimization was started in the treatment planning system followed by dose delivery. 3D Cine-MR imaging was started simultaneously with beam-on and acquired over the full beam-on period. Prostate intrafraction motion in this cine-MR was determined with a previously validated soft-tissue contrast based tracking algorithm. In addition, absolute accuracy of the method was determined using a 4D phantom.
Prostate motion was completely automatically determined over the full on-couch period (approx. 45 min) with no identified mis-registrations. The translation 95% confidence intervals are within clinically applied margins of 5 mm, and plan adaption for intrafraction motion was required in only 4 out of 100 fractions.
This is the first study to investigate prostate intrafraction motions during entire MR-guided RT sessions on an MR-Linac. We have shown that high quality 3D cine-MR imaging and prostate tracking during RT is feasible with beam-on. The clinically applied margins of 5 mm have proven to be sufficient for these treatments and may potentially be further reduced using intrafraction plan adaptation guided by cine-MR imaging.
The triage theory posits that modest micronutrient deficiencies may induce reallocation of nutrients to processes necessary for immediate survival at the expense of long-term health. Neglected ...processes could in time contribute to the onset of age-related diseases, in which oxidative stress is believed to be a major factor. Vitamin B
(B12) appears to possess antioxidant properties. This review aims to summarise the potential antioxidant mechanisms of B12 and investigate B12 status in relation to oxidative stress markers. A systematic query-based search of PubMed was performed to identify eligible publications. The potential antioxidant properties of B12 include: (1) direct scavenging of reactive oxygen species (ROS), particularly superoxide; (2) indirect stimulation of ROS scavenging by preservation of glutathione; (3) modulation of cytokine and growth factor production to offer protection from immune response-induced oxidative stress; (4) reduction of homocysteine-induced oxidative stress; and (5) reduction of oxidative stress caused by advanced glycation end products. Some evidence appears to suggest that lower B12 status is related to increased pro-oxidant and decreased antioxidant status, both overall and for subclinically deficient individuals compared to those with normal B12 status. However, there is a lack of randomised controlled trials and prospective studies focusing specifically on the relation between B12 and oxidative stress in humans, resulting in a low strength of evidence. Further work is warranted.
Fe–N-heterocyclic carbene (NHC) complexes attract increasing attention as photosensitisers and photoredox catalysts. Such applications generally rely on sufficiently long excited state lifetimes and ...efficient bimolecular quenching, which leads to there being few examples of successful usage of Fe–NHC complexes to date. Here, we have employed Fe(iii)(btz)33+ (btz = (3,3′-dimethyl-1,1′-bis(p-tolyl)-4,4′-bis(1,2,3-triazol-5-ylidene))) in the addition of alkyl halides to alkenes and alkynes via visible light-mediated atom transfer radical addition (ATRA). Unlike other Fe–NHC complexes, Fe(iii/ii)(btz)33+/2+ benefits from sizable charge transfer excited state lifetimes ≥0.1 ns in both oxidation states, and the Fe(iii) 2LMCT and Fe(ii) 3MLCT states are strong oxidants and reductants, respectively. The combined reactivity of both excited states enables efficient one-electron reduction of the alkyl halide substrate under green light irradiation. The two-photon mechanism proceeds via reductive quenching of the Fe(iii) 2LMCT state by a sacrificial electron donor and subsequent excitation of the Fe(ii) product to its highly reducing 3MLCT state. This route is shown to be more efficient than the alternative, where oxidative quenching of the less reducing Fe(iii) 2LMCT state by the alkyl halide drives the reaction, in the absence of a sacrificial electron donor.
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