Study on the reusability of fluorescent nuclear track detectors using optical bleaching

Fluorescent nuclear track detectors (FNTDs) based on Al${_2}$O${_3}$:C,Mg crystals are luminescent detectors that can be used for dosimetry and detection of charged particles and neutrons. These detectors can be utilised for imaging applications where a reasonably high track density, approximately of the order of 1 $\times$ $10^4$ tracks in an area of 100 $\times$ 100 $\mu$m$^2$, is required. To investigate the reusability of FNTDs for imaging applications, we present an approach to perform optical bleaching under the required track density conditions. The reusability was assessed through seven irradiation-bleaching cycles. For the irradiation, the studied FNTD was exposed to alpha-particles from an $^{241}$Am radioactive source. The optical bleaching was performed by means of ultraviolet laser light with a wavelength of 355 nm. Three dedicated regions on a single FNTD with different accumulated track densities and bleaching conditions were investigated. After every irradiation-bleaching cycle, signal-to-noise ratio was calculated to evaluate FNTD performance. It is concluded that FNTDs can be reused at least seven times for applications where accumulation of a high track density is required

Resting Energy Expenditure in Older Inpatients: A Comparison of Prediction Equations and Measurements

Determining energy requirements are an important component of nutritional support for patients with malnutrition; however, the validity of prediction equations for resting energy expenditure (REE) is disputed in older hospitalized patients. We aimed to assess the validity of these equations in older hospitalized patients in Japan. This was a single-center, cross-sectional study of 100 patients aged ≥70 years, hospitalized between January 2020 and December 2021. REE was measured using an indirect calorimeter and was compared to the predicted values calculated from five REE prediction equations. The mean (95% confidence interval) measured REE was 968.1 (931.0, 1005.3) kcal/day, and the mean predicted REE was higher for the FAO/WHO/UNU (1014.3 [987.1, 1041.6] kcal/day, p = 0.164) and Schofield (1066.0 [1045.8, 1086.2] kcal/day, p < 0.001) equations and lower for the Harris-Benedict (898.6 [873.1, 924.1] kcal/day, p = 0.011), Ganpule (830.1 [790.3, 869.9] kcal/day, p < 0.001), and body weight (kg) × 20 (857.7 [821.9, 893.5] kcal/day, p < 0.001) equations. In the age group analysis, none of the predicted values were within a 10% error for more than 80% of patients aged 70–89 years and ≥90 years. The five REE prediction equations did not provide accurate estimates. Validated REE prediction equations need to be developed for older hospitalized patients

Impact of sleep disordered breathing on performance in judo players

ObjectivePrevious studies have suggested that young sports players may suffer from sleep disordered breathing (SDB). It was hypothesised that SDB in heavy-class judo players was far more prevalent than expected and that it could reduce judo performance, which could be improved by appropriate therapies. To address this, the present study estimated the percentage of heavy-class judo players with SDB and investigated the effect of SDB treatment on judo performance.MethodsWe enrolled 19 young judo players from a university judo team with body weight >100 kg and/or body mass index >30 kg/m2. Both excessive daytime sleepiness (EDS) and respiratory disturbance index (RDI) were evaluated using the Epworth Sleepiness Scale (ESS) and an overnight type 3 sleep monitor.ResultsThe percentages of young heavyweight-class judo players with EDS (ESS ≥11) and those with SDB (RDI ≥5) were both 63%, which was unexpectedly high for the age class. Seven of the participants underwent continuous positive airway pressure therapy, which improved both RDI and ESS scores (p<0.05 for each) and subsequently the sleep quality and judo performance of the participants.ConclusionsOur study indicates that young judo players might silently suffer from SDB, leading to poorer judo performance and to future cardiovascular diseases. Clinicians should be aware of the possible presence of SDB in young sports players and consider the application of diagnostic and therapeutic remedies

An assessment of the effects of ectopic gp91phox expression in XCGD iPSC-derived neutrophils

For the treatment of monogenetic hematological disorders, restoration of transgene expression in affected cell populations is generally considered to have beneficial effects. However, X-linked chronic granulomatous disease (XCGD) is unique since the appearance of functional neutrophils in the peripheral blood following hematopoietic stem cell gene therapy is transient only. One contributing factor could be the occurrence of detrimental effects secondary to ectopic gp91phox expression in neutrophils, which has not been formally demonstrated previously. This study uses iPSCs to model XCGD, which allows the process of differentiation to be studied intensely in vitro. Alpharetroviral vectors carrying a ubiquitous promoter were used to drive the âectopicâ expression of codon optimized gp91phox cDNA. In the mature fraction of neutrophils differentiated from transduced XCGD-iPSCs, cellular recovery in terms of gp91phox expression and reactive oxygen species production was abruptly lost before cells had fully differentiated. Most critically, ectopic gp91phox expression could be identified clearly in the developing fraction of the transduced groups, which appeared to correspond with reduced cell viability. It is possible that this impedes further differentiation of developing neutrophils. Therefore, affording cellular protection from the detrimental effects of ectopic gp91phox expression may improve XCGD clinical outcomes

4-Phenylbutyrate ameliorates apoptotic neural cell death in Down syndrome by reducing protein aggregates

Abstract Individuals with Down syndrome (DS) commonly show unique pathological phenotypes throughout their life span. Besides the specific effects of dosage-sensitive genes on chromosome 21, recent studies have demonstrated that the gain of a chromosome exerts an adverse impact on cell physiology, regardless of the karyotype. Although dysregulated transcription and perturbed protein homeostasis are observed in common in human fibroblasts with trisomy 21, 18, and 13, whether and how this aneuploidy-associated stress acts on other cell lineages and affects the pathophysiology are unknown. Here, we investigated cellular stress responses in human trisomy 21 and 13 neurons differentiated from patient-derived induced pluripotent stem cells. Neurons of both trisomies showed increased vulnerability to apoptotic cell death, accompanied by dysregulated protein homeostasis and upregulation of the endoplasmic reticulum stress pathway. In addition, misfolded protein aggregates, comprising various types of neurodegenerative disease-related proteins, were abnormally accumulated in trisomic neurons. Intriguingly, treatment with sodium 4-phenylbutyrate, a chemical chaperone, successfully decreased the formation of protein aggregates and prevented the progression of cell apoptosis in trisomic neurons. These results suggest that aneuploidy-associated stress might be a therapeutic target for the neurodegenerative phenotypes in DS