Imaging performance of a LaBr3:Ce scintillation detector for photon counting x-ray computed tomography: Simulation study.

BACKGROUND: Photon counting detectors (PCDs) for x-ray computed tomography (CT) are the future of CT imaging. At present, semiconductor-based PCDs such as cadmium telluride (CdTe), cadmium zinc telluride, and silicon have been either used or investigated for clinical PCD CT. Unfortunately, all of them have the same major challenges, namely high cost and limited spectral signal-to-noise ratio (SNR). Recent studies showed that some high-quality scintillators, such as lanthanum bromide doped with cerium (LaBr3:Ce), are less expensive and almost as fast as CdTe. PURPOSE: The objective of this study is to assess the performance of a LaBr3:Ce PCD for clinical x-ray CT. METHODS: We performed Monte Carlo simulations and compared the performance of 3 mm thick LaBr3:Ce and 2 mm thick CdTe for PCD CT with x-rays at 120 kVp and 20-1000 mA. The two PCDs were operated with either a threshold-subtract (TS) counting scheme or a direct energy binning (DB) counting scheme. The performance was assessed in terms of the accuracy of registered spectra, counting capability, and count-rate-dependent spectral imaging-task performance, for conventional CT imaging, water-bone material decomposition, and K-edge imaging with tungsten as the K-edge material. The performance for these imaging-tasks was quantified by nCRLB, that is, the Cramér-Rao lower bound on the variance of basis line-integral estimation, normalized by the corresponding value of CdTe at 20 mA. RESULTS: The spectrum recorded by CdTe was distorted significantly due to charge sharing, whereas the spectra recorded by LaBr3:Ce better matched the incident spectrum. The dead time, estimated by fitting a paralyzable detector model to the count-rate curves, was 20.7, 15.0, 37.2, and 13.0 ns for CdTe with TS, CdTe with DB, LaBr3:Ce with TS, and LaBr3:Ce with DB, respectively. Conventional CT imaging showed an adverse effect of reduced geometrical efficiency due to optical reflectors in LaBr3:Ce PCD. The nCRLBs (a lower value indicates a better SNR) for CdTe with TS, CdTe with DB, LaBr3:Ce with TS, LaBr3:Ce with DB, and the ideal PCD, were 1.00 ± 0.01, 1.00 ± 0.01, 1.18 ± 0.02, 1.18 ± 0.02, and 0.79 ± 0.01, respectively, at 20 mA. The nCRLBs for water-bone material decomposition, in the same order, were 1.00 ± 0.02, 1.00 ± 0.02, 0.85 ± 0.02, 0.85 ± 0.02, and 0.24 ± 0.02, respectively, at 20 mA; and 0.98 ± 0.02, 0.98 ± 0.02, 1.09 ± 0.02, 0.83 ± 0.02, and 0.24 ± 0.02, respectively, at 1000 mA. Finally, the nCRLBs for K-edge imaging, the most demanding task among the five, were 1.00 ± 0.02, 1.00 ± 0.02, 0.55 ± 0.02, 0.55 ± 0.02, and 0.13 ± 0.02, respectively, at 20 mA; and 2.45 ± 0.02, 2.29 ± 0.02, 3.12 ± 0.02, 2.11 ± 0.02, and 0.13 ± 0.02, respectively, at 1,000 mA. CONCLUSION: The Monte Carlo simulations showed that, compared to CdTe with either TS or DB, LaBr3:Ce with DB provided more accurate spectra, comparable or better counting capability, and superior spectral imaging-task performances, that is, water-bone material decomposition and K-edge imaging. CdTe had a better performance than LaBr3:Ce for the conventional CT imaging task due to its higher geometrical efficiency. LaBr3:Ce PCD with DB scheme may be an excellent alternative option for CdTe PCD.

Creatine supplementation does not add to resistance training effects in prostate cancer patients under androgen deprivation therapy: A double-blind randomized trial.

OBJECTIVES: Androgen deprivation therapy (ADT) leads to loss of lean mass (LM) and reduced strength and physical function. Resistance exercise alone can counteract these changes; however, it is unknown if the addition of creatine supplementation can further protect against these ADT-induced toxicities. We compared the effects of creatine supplementation with resistance exercise versus resistance exercise alone in patients with prostate cancer undergoing ADT on LM, muscle strength, and physical function. DESIGN: A 12-week randomized trial. METHODS: Men with prostate cancer receiving ADT (n = 30) were randomized to either resistance exercise + placebo (PLA) or resistance exercise + creatine (SUPP), with both groups undertaking supervised exercise 3 days per week. Outcomes included whole body and appendicular LM and fat mass (FM) assessed by dual-energy X-ray absorptiometry, as well as muscle strength (chest press, seated low, leg press), and physical function (timed up-and-go, chair rise, 400-m walk) assessed at baseline and following the intervention. RESULTS: Patients were aged 59-84 years with a BMI of 28.6 kg·m-2. PLA completed a mean of 30 sessions (83 %) and SUPP a mean of 33 sessions (92 %). Despite similar within-group improvements (p < 0.05) in whole-body LM (PLA +0.6 kg, SUPP +1.3 kg), appendicular LM (PLA +0.5 kg, SUPP +0.6 kg), muscle strength (PLA +8.8-49.3 kg, SUPP +9.4-40.4 kg) and physical function, there were no between group differences (p = 0.078-0.951). No adverse events were reported due to creatine supplementation or resistance exercise. CONCLUSIONS: A short-term program of resistance exercise alone results in meaningful improvements in LM, muscle strength and physical function, with no additional effects of creatine supplementation.

Binge ethanol consumption can be attenuated by systemic administration of minocycline and is associated with enhanced neuroinflammation in the central amygdala.

Alcohol use disorder (AUD) has a complicated pathophysiology. Binge ethanol intoxication may produce long-lasting changes throughout extended amygdala neurocircuitry including neuroinflammation, often leading to relapse. Therefore, understanding the role of binge drinking induced neuroinflammation on extended amygdala neurocircuitry is critically important for treatment. We sought to understand the role of neuroinflammation in a naturalized form of rodent binge ethanol drinking (Drinking in the Dark (DID)). In a 5-week DID paradigm, we demonstrate that acute intraperitoneal (IP) injection of the anti-inflammatory drug minocycline significantly reduced binge drinking repeatedly in male and female Cx3CR1-GFP and C57BL/6J mice. Importantly, IP administration transiently decreased intermittent access sucrose consumption, was not observed on the second IP injection, but did not significantly alter food or water consumption, suggesting that minocycline may produce initial acute aversive effects and may not alter long-term consumption of natural rewards. Examination of rodent behaviors post ethanol binge drinking reveals no lasting effects of minocycline treatment on locomotion or anxiety-like behavior. To assess neuroinflammation, we developed a novel analysis method using a Matlab image analysis script, which allows for non-biased skeletonization and evaluation of microglia morphology to determine a possible activation state in Cx3CR1-GFP knock-in mice after repeated DID. We observed significant morphological changes of microglia within the CeA, but no differences in the BLA. Taken together, this study demonstrates repeated binge ethanol consumption can produce significant levels of microglia morphology changes within the CeA, and that immunomodulatory therapies may be an intriguing pharmacological candidate for the treatment of AUD.

Effects of short- and long-term exercise training on cancer cells in vitro: Insights into the mechanistic associations.

Exercise is a therapeutic approach in cancer treatment, providing several benefits. Moreover, exercise is associated with a reduced risk for developing a range of cancers and for their recurrence, as well as with improving survival, even though the underlying mechanisms remain unclear. Preclinical and clinical evidence shows that the acute effects of a single exercise session can suppress the growth of various cancer cell lines in vitro. This suppression is potentially due to altered concentrations of hormones (e.g., insulin) and cytokines (e.g., tumor necrosis factor alpha and interleukin 6) after exercise. These factors, known to be involved in tumorigenesis, may explain why exercise is associated with reduced cancer incidence, recurrence, and mortality. However, the effects of short- (<8 weeks) and long-term (≥8 weeks) exercise programs on cancer cells have been reported with mixed results. Although more research is needed, it appears that interventions incorporating both exercise and diet seem to have greater inhibitory effects on cancer cell growth in both apparently healthy subjects as well as in cancer patients. Although speculative, these suppressive effects on cancer cells may be driven by changes in body weight and composition as well as by a reduction in low-grade inflammation often associated with sedentary behavior, low muscle mass, and excess fat mass in cancer patients. Taken together, such interventions could alter the systemic levels of suppressive circulating factors, leading to a less favorable environment for tumorigenesis. While regular exercise and a healthy diet may establish a more cancer-suppressive environment, each acute bout of exercise provides a further "dose" of anti-cancer medicine. Therefore, integrating regular exercise could potentially play a significant role in cancer management, highlighting the need for future investigations in this promising area of research.

Immediate Versus Delayed Exercise on Health-related Quality of Life in Patients Initiating Androgen Deprivation Therapy: Results from a Year-long Randomised Trial.

BACKGROUND AND OBJECTIVE: An array of treatment-related toxicities result from androgen deprivation therapy (ADT) in patients with prostate cancer (PCa), compromising function and health-related quality of life (HRQoL). Exercise has been demonstrated to counter a number of these adverse effects including decreased HRQoL; however, when exercise should be initiated is less clear. This study aims to examine whether commencing exercise when ADT is initiated rather than later during treatment is more effective in countering adverse effects on HRQoL. METHODS: Men with PCa (48-84 yr) initiating ADT were randomised to immediate exercise (IMEX; n = 54) or delayed exercise (DEL; n = 48) for 12 mo. IMEX consisted of 6 mo of supervised resistance/aerobic/impact exercise commenced at the initiation of ADT with 6 mo of follow-up. DEL consisted of 6 mo of usual care followed by 6 mo of the same exercise programme. HRQoL was assessed using the Short Form-36 at baseline and 6 and 12 mo. Intention to treat was utilised for the analyses that included group × time repeated-measures analysis of variance using log transformed data. KEY FINDINGS AND LIMITATIONS: There were a significant group × time interaction for the physical functioning domain (p = 0.045) and physical component summary score (p = 0.005), and a significant time effect for bodily pain (p < 0.001) and vitality domains (p < 0.001), with HRQoL maintained in IMEX and declining in DEL at 6 mo. Exercise in DEL reversed declines in vitality and in the physical component summary score, with no differences at 12 mo compared with baseline. Limitations include treatment alterations during the intervention. CONCLUSIONS AND CLINICAL IMPLICATIONS: Concurrently initiating exercise and ADT in patients with PCa preserves HRQoL, whereas exercise initiated while on established ADT regimens reverses declines in some HRQoL domains. PATIENT SUMMARY: To avoid initial treatment-related adverse effects on health-related quality of life, exercise medicine should be initiated at the start of treatment.

The rat bladder umbrella cell keratin network: organization, dependence on the plectin cytolinker, and responses to bladder filling.

The keratin cytoskeleton and associated desmosomes contribute to the mechanical stability of epithelial tissues, but their organization in native bladder umbrella cells and their responses to bladder filling are poorly understood. Using whole rat bladders in conjunction with confocal microscopy, super-resolution image processing, 3D image reconstruction, and platinum replica electron microscopy, we identified a cortical cytoskeleton network in umbrella cells that was organized as a dense tile-like mesh comprised of tesserae bordered by cortical actin filaments, filled with keratin filaments, and crosslinked by plectin. Below these tesserae, keratin formed a subapical meshwork and at the cell periphery a band of keratin was linked via plectin to the junction-associated actin ring. Disruption of plectin led to focal keratin network dissolution, loss of the junction-associated keratin, and defects in cell-cell adhesion. During bladder filling, a junction-localized necklace of desmosomes expanded, and a subjacent girded layer formed linking the keratin network to desmosomes, including those at the umbrella cell-intermediate cell interface. Our studies reveal a novel tile- and mesh-like organization of the umbrella cell keratin network that is dependent on plectin, that reorganizes in response to bladder filling, and that likely serves to maintain umbrella cell continuity in the face of mechanical distension. [Media: see text] [Media: see text] [Media: see text] [Media: see text] [Media: see text] [Media: see text].

Immunization of cows with HIV envelope trimers generates broadly neutralizing antibodies to the V2-apex from the ultralong CDRH3 repertoire.

The generation of broadly neutralizing antibodies (bnAbs) to conserved epitopes on HIV Envelope (Env) is one of the cornerstones of HIV vaccine research. The animal models commonly used for HIV do not reliably produce a potent broadly neutralizing serum antibody response, with the exception of cows. Cows have previously produced a CD4 binding site response by homologous prime and boosting with a native-like Env trimer. In small animal models, other engineered immunogens were shown to focus antibody responses to the bnAb V2-apex region of Env. Here, we immunized two groups of cows (n = 4) with two regimens of V2-apex focusing Env immunogens to investigate whether antibody responses could be generated to the V2-apex on Env. Group 1 was immunized with chimpanzee simian immunodeficiency virus (SIV)-Env trimer that shares its V2-apex with HIV, followed by immunization with C108, a V2-apex focusing immunogen, and finally boosted with a cross-clade native-like trimer cocktail. Group 2 was immunized with HIV C108 Env trimer followed by the same HIV trimer cocktail as Group 1. Longitudinal serum analysis showed that one cow in each group developed serum neutralizing antibody responses to the V2-apex. Eight and 11 bnAbs were isolated from Group 1 and Group 2 cows, respectively, and showed moderate breadth and potency. Potent and broad responses in this study developed much later than previous cow immunizations that elicited CD4bs bnAbs responses and required several different immunogens. All isolated bnAbs were derived from the ultralong CDRH3 repertoire. The finding that cow antibodies can target more than one broadly neutralizing epitope on the HIV surface reveals the generality of elongated structures for the recognition of highly glycosylated proteins. The exclusive isolation of ultralong CDRH3 bnAbs, despite only comprising a small percent of the cow repertoire, suggests these antibodies outcompete the long and short CDRH3 antibodies during the bnAb response.

Modulation of antigen delivery and lymph node activation in non-human primates by saponin adjuvant SMNP.

Saponin-based vaccine adjuvants are potent in preclinical animal models and humans, but their mechanisms of action remain poorly understood. Here, using a stabilized HIV envelope trimer immunogen, we carried out studies in non-human primates (NHPs) comparing the most common clinical adjuvant alum with Saponin/MPLA Nanoparticles (SMNP), a novel ISCOMs-like adjuvant. SMNP elicited substantially stronger humoral immune responses than alum, including 7-fold higher peak antigen-specific germinal center B cell responses, 18-fold higher autologous neutralizing antibody titers, and higher levels of antigen-specific plasma and memory B cells. PET-CT imaging in live NHPs showed that, unlike alum, SMNP promoted rapid antigen accumulation in both proximal and distal lymph nodes (LNs). SMNP also induced strong type I interferon transcriptional signatures, expansion of innate immune cells, and increased antigen presenting cell activation in LNs. These findings indicate that SMNP promotes multiple facets of the early immune response relevant for enhanced immunity to vaccination.

Unacylated Ghrelin Protects Against Age-Related Loss of Muscle Mass and Contractile Dysfunction in Skeletal Muscle.

Sarcopenia, the progressive loss of muscle mass and function, universally affects older adults and is closely associated with frailty and reduced quality of life. Despite the inevitable consequences of sarcopenia and its relevance to healthspan, no pharmacological therapies are currently available. Ghrelin is a gut-released hormone that increases appetite and body weight through acylation. Acylated ghrelin activates its receptor, growth hormone secretagogue receptor 1a (GHSR1a), in the brain by binding to it. Studies have demonstrated that acyl and unacylated ghrelin (UnAG) both have protective effects against acute pathological conditions independent of receptor activation. Here, we investigated the long-term effects of UnAG in age-associated muscle atrophy and contractile dysfunction in mice. Four-month-old and 18-month-old mice were subjected to either UnAG or control treatment for 10 months. UnAG did not affect food consumption or body weight. Gastrocnemius and quadriceps muscle weights were reduced by 20%-30% with age, which was partially protected against by UnAG. Specific force, force per cross-sectional area, measured in isolated extensor digitorum longus muscle was diminished by 30% in old mice; however, UnAG prevented the loss of specific force. UnAG also protected from decreases in mitochondrial respiration and increases in hydrogen peroxide generation of skeletal muscle of old mice. Results of bulk mRNA-seq analysis and our contractile function data show that UnAG reversed neuromuscular junction impairment that occurs with age. Collectively, our data revealed the direct role of UnAG in mitigating sarcopenia in mice, independent of food consumption or body weight, implicating UnAG treatment as a potential therapy against sarcopenia.

Hepatic Proteomic Changes Associated with Liver Injury Caused by Alcohol Consumption in Fpr2-/- Mice.

Alcohol-associated liver disease (ALD) is a prevalent medical problem with limited effective treatment strategies. Although many biological processes contributing to ALD have been elucidated, a complete understanding of the underlying mechanisms is still lacking. The current study employed a proteomic approach to identify hepatic changes resulting from ethanol (EtOH) consumption and the genetic ablation of the formyl peptide receptor 2 (FPR2), a G-protein coupled receptor known to regulate multiple signaling pathways and biological processes, in a mouse model of ALD. Since previous research from our team demonstrated a notable reduction in hepatic FPR2 protein levels in patients with alcohol-associated hepatitis (AH), the proteomic changes in the livers of Fpr2-/- EtOH mice were compared to those observed in patients with AH in order to identify common hepatic proteomic alterations. Several pathways linked to exacerbated ALD in Fpr2-/- EtOH mice, as well as hepatic protein changes resembling those found in patients suffering from AH, were identified. These alterations included decreased levels of coagulation factors F2 and F9, as well as reduced hepatic levels of glutamate-cysteine ligase catalytic subunit (GCLC) and total glutathione in Fpr2-/- EtOH compared to WT EtOH mice. In conclusion, the data suggest that FPR2 may play a regulatory role in hepatic blood coagulation and the antioxidant system, both in a pre-clinical model of ALD and in human AH, however further experiments are required to validate these findings.

Effects of a 6-month dual-task, power-based exercise program on cognitive function, neurological and inflammatory markers in older adults: secondary analysis of a cluster randomised controlled trial.

Functional power-based exercise training can improve physical performance in older adults and cognitive training can improve measures of cognition, but their combined effects on cognition and related risk factors (neurological and inflammatory markers) remains uncertain. This 6-month cluster randomised controlled trial evaluated the effectiveness of dual-task functional power training (DT-FPT) on cognition and circulating neurological and inflammatory markers in older adults at increased falls risk, and whether intervention responses varied by apolipoprotein-E (ApoE) and brain derived neurotrophic factor (BDNF) polymorphisms. Three hundred residents aged ≥ 65 years at increased falls risk residing in 22 independent-living retirement communities, were randomised by village, to DT-FPT (n = 156, 11 villages) involving a multi-component power-based training program performed simultaneously with cognitive and/or motor tasks (45-60 min, 2/week), or a usual care control (CON) group (n = 144, 11 villages). Cognition (computerized CogState battery), inflammatory cytokines, BDNF, insulin-like growth factor-1, vascular endothelial growth factor, amyloid ß (1-40) and (1-42) were assessed at baseline and 6-months. Overall, 233 (78%) participants completed the intervention and adherence averaged 50.1%. DT-FPT led to a net 0.18-0.20 SD benefit versus CON in psychomotor ability/attention and reaction time/attention (both P < 0.05). There were no significant intervention effects on circulating markers, except for a net 10.5% benefit in amyloid ß (1-40) in DT-FPT versus CON (P < 0.05). Responses were not influenced by APOE or BDNF genotype. In conclusion, DT-FPT in older adults at increased falls risk can provide some cognitive benefits, but these were not related to corresponding changes in inflammatory or neurological markers or influenced by genotype. Australian New Zealand Clinical Trials Registry (ACTRN12613001161718). http://www.anzctr.org.au/ This project was funded by a grant from the National Health and Medical Research Council (NHMRC) Project (APP1046267).

Passive infusion of an S2-Stem broadly neutralizing antibody protects against SARS-CoV-2 infection and lower airway inflammation in rhesus macaques.

The continued evolution of SARS-CoV-2 variants capable of subverting vaccine and infection-induced immunity suggests the advantage of a broadly protective vaccine against betacoronaviruses (ß-CoVs). Recent studies have isolated monoclonal antibodies (mAbs) from SARS-CoV-2 recovered-vaccinated donors capable of neutralizing many variants of SARS-CoV-2 and other ß-CoVs. Many of these mAbs target the conserved S2 stem region of the SARS-CoV-2 spike protein, rather the receptor binding domain contained within S1 primarily targeted by current SARS-CoV-2 vaccines. One of these S2-directed mAbs, CC40.8, has demonstrated protective efficacy in small animal models against SARS-CoV-2 challenge. As the next step in the pre-clinical testing of S2-directed antibodies as a strategy to protect from SARS-CoV-2 infection, we evaluated the in vivo efficacy of CC40.8 in a clinically relevant non-human primate model by conducting passive antibody transfer to rhesus macaques (RM) followed by SARS-CoV-2 challenge. CC40.8 mAb was intravenously infused at 10mg/kg, 1mg/kg, or 0.1 mg/kg into groups (n=6) of RM, alongside one group that received a control antibody (PGT121). Viral loads in the lower airway were significantly reduced in animals receiving higher doses of CC40.8. We observed a significant reduction in inflammatory cytokines and macrophages within the lower airway of animals infused with 10mg/kg and 1mg/kg doses of CC40.8. Viral genome sequencing demonstrated a lack of escape mutations in the CC40.8 epitope. Collectively, these data demonstrate the protective efficiency of broadly neutralizing S2-targeting antibodies against SARS-CoV-2 infection within the lower airway while providing critical preclinical work necessary for the development of pan-ß-CoV vaccines.

Clinical Outcomes of Non-Stent-Based Interventions for Symptomatic Below-the-Knee Peripheral Artery Disease in the Excellence in Peripheral Artery Disease (XLPAD) Registry.

For endovascular treatment of below-the-knee (BTK) peripheral artery disease (PAD), independently adjudicated real-world outcomes comparing non-stent-based balloon angioplasty (percutaneous transluminal angioplasty) and adjunctive treatments with or without a concomitant ipsilateral femoropopliteal (FP) artery intervention are scarce. A total of 1,060 patients from the multicenter XLPAD registry who underwent non-stent-based BTK PAD intervention between 2006 and 2021 were included. The primary outcome was the 1-year incidence of major adverse limb events (MALEs), a composite of all-cause death, any amputation, or clinically driven repeat revascularization. A total of 566 patients underwent BTK and 494 BTK + FP interventions; 72% were men, with a mean age of 68.4 ± 10.9 years. Diabetes mellitus was more prevalent in the BTK-only group (76.5% vs 69%, p = 0.006). Mean Rutherford class was 4.2 ± 1.18; chronic limb-threatening ischemia was more frequent in the BTK group (55.3% vs 49%, p = 0.040). Moderate to severe calcification was more frequent in the BTK + FP group (21.2% vs 27.1%, p = 0.024), as was lesion length (110.6 ± 77.3 vs 135.4 ± 86.3 mm, p <0.001). Nearly 81% of lesions were treated with percutaneous transluminal angioplasty. Drug-coated balloon (1.6% vs 14%, p <0.001) and atherectomy (38% vs 58.5%, p <0.001) use was more frequent in the BTK + FP group. The rate of procedural success was higher in the BTK + FP group (86% vs 91%, p = 0.009), with amputation being the most common complication at 3.3% within 30 days after the procedure. The rates of 1-year MALE (21.2% vs 22.3%, p = 0.675) and mortality (4.6% vs 3.4%, p = 0.3) were similar between the BTK and BTK + FP groups. Nonstent treatment for BTK PAD with concomitant FP intervention leads to high procedural success and similar rates of 1-year MALE compared with isolated BTK intervention. Condensed Abstract: The vast majority of below-the-knee (BTK) peripheral artery disease (PAD) interventions are performed with balloon angioplasty. Presence of inflow femoropopliteal PAD in patients who undergo BTK interventions can affect the outcome of the procedure. This report explores immediate procedural success and major adverse limb events at 1 year after balloon angioplasty treatment for isolated BTK PAD and in patients who underwent an additional femoropopliteal PAD intervention.

Phosphodiesterase-4 Inhibitors Increase Pigment Cell Proliferation and Melanization in Cultured Melanocytes and within a 3-Dimensional Skin Equivalent Model.

Vitiligo is a common chronic autoimmune disease characterized by white macules and patches of the skin, having a negative impact on patients' life and without any definitive cure at present. Identification of new compounds to reverse depigmentation is therefore a pressing need for this disease. The pharmacologic compounds phosphodiesterase-4 inhibitors (PDE4is) are small molecules with immunomodulatory properties used for treatment of inflammatory dermatoses. PDE4is have shown repigmentation effects in patients with vitiligo, in some case reports. We characterized the proliferative and melanogenic potential of 2 known PDE4is-crisaborole and roflumilast-and of a more recently designed compound, PF-07038124. We used 2 in vitro model systems-the primary human melanocyte culture and a 3-dimensional cocultured skin model (MelanoDerm)-with an exploratory testing platform composed of complementary assays (spectrophotometry, melanin and proliferation assays, immunostaining, Fontana-Masson staining, RT-qPCR, western blot, and whole-transcriptome RNA sequencing). We identified that treatment with PDE4is was associated with increased melanocyte proliferation and melanization in both in vitro models and with increase in the melanogenic genes and proteins expression in cultured melanocytes. These effects were found to be enhanced by addition of α-melanocyte-stimulating hormone. Our findings support the further evaluation of PDE4is with or without α-melanocyte-stimulating hormone agonists in vitiligo trials.

Identification of glycosyltransferases mediating 2-O-arabinopyranosyl and 2-O-galactosyl substitutions of glucuronosyl side chains of xylan.

Xylan is one of the major hemicelluloses in plant cell walls and its xylosyl backbone is often decorated at O-2 with glucuronic acid (GlcA) and/or methylglucuronic acid (MeGlcA) residues. The GlcA/MeGlcA side chains may be further substituted with 2-O-arabinopyranose (Arap) or 2-O-galactopyranose (Gal) residues in some plant species, but the enzymes responsible for these substitutions remain unknown. During our endeavor to investigate the enzymatic activities of Arabidopsis MUR3-clade members of the GT47 glycosyltransferase family, we found that one of them was able to transfer Arap from UDP-Arap onto O-2 of GlcA side chains of xylan, and thus it was named xylan 2-O-arabinopyranosyltransferase 1 (AtXAPT1). The function of AtXAPT1 was verified in planta by its T-DNA knockout mutation showing a loss of the Arap substitution on xylan GlcA side chains. Further biochemical characterization of XAPT close homologs from other plant species demonstrated that while the poplar ones had the same catalytic activity as AtXAPT1, those from Eucalyptus, lemon-scented gum, sea apple, 'Ohi'a lehua, duckweed and purple yam were capable of catalyzing both 2-O-Arap and 2-O-Gal substitutions of xylan GlcA side chains albeit with differential activities. Sequential reactions with XAPTs and glucuronoxylan methyltransferase 3 (GXM3) showed that XAPTs acted poorly on MeGlcA side chains, whereas GXM3 could efficiently methylate arabinosylated or galactosylated GlcA side chains of xylan. Furthermore, molecular docking and site-directed mutagenesis analyses of Eucalyptus XAPT1 revealed critical roles of several amino acid residues at the putative active site in its activity. Together, these findings establish that XAPTs residing in the MUR3 clade of family GT47 are responsible for 2-O-arabinopyranosylation and 2-O-galactosylation of GlcA side chains of xylan.

Visualisation of in vivo protein synthesis during mycobacterial infection through [68Ga]Ga-DOTA-puromycin µPET/MRI.

Radiolabelled puromycin analogues will allow the quantification of protein synthesis through nuclear medicine-based imaging. A particularly useful application could be the non-invasive longitudinal visualisation of mycobacterial activity through direct quantification of puromycin binding. This study assesses the value of [68Ga]Ga-DOTA-puromycin in the visualisation of mycobacteria through positron emission tomography combined with magnetic resonance imaging (µPET/MRI). The radiopharmaceutical was produced by previously published and validated methods. [68Ga]Ga-DOTA-Puromycin imaging was performed on severe immunodeficient mice infected with Bacille Calmette-Guérin-derived M. Bovis (BCG). Acute and chronic infection stages were examined by µPET/MRI. A follow-up group of animals acted as controls (animals bearing S. aureus-derived infection and sterile inflammation) to assess tracer selectivity. [68Ga]Ga-DOTA-puromycin-µPET/MRI images revealed the acute, widespread infection within the right upper shoulder and armpit. Also, [68Ga]Ga-DOTA-puromycin signal sensitivity measured after a 12-week period was lower than that of [18F]FDG-PET in the same animals. A suitable correlation between normalised uptake values (NUV) and gold standard histopathological analysis confirms accurate tracer accumulation in viable bacteria. The radiopharmaceutical showed infection selectivity over inflammation but accumulated in both M. Bovis and S. Aureus, lacking pathogen specificity. Overall, [68Ga]Ga-DOTA-puromycin exhibits potential as a tool for non-invasive protein synthesis visualization, albeit without pathogen selectivity.

Assessing Sarcopenia in Advanced-Stage Ovarian Cancer Patients Undergoing Neoadjuvant Chemotherapy: A Case Series.

OBJECTIVES: In ovarian and other cancers, low muscle mass and density are associated with poorer clinical outcomes. However, screening for cancer-related sarcopenia (typically defined as low muscle mass) is not routinely conducted. The European Working Group on Sarcopenia in Older People (EWGSOP) recommends an algorithm for sarcopenia screening and diagnosis in clinical settings, with sarcopenia based on muscle strength and mass, and severity on physical performance. We explored the application of the EWGSOP2 algorithm to assess sarcopenia in six ovarian cancer patients receiving neoadjuvant chemotherapy. METHODS: We assessed sarcopenia risk with the SARC-F screening questionnaire (at risk ≥4 points), muscle strength with a handgrip strength test (cut point <16 kg) and five times sit-to-stand test (cut point >15 s), muscle mass by skeletal muscle index (SMI in cm2/m2 from a single computed tomography [CT] image; cut point <38.5 cm2/m2), and physical performance with a 4-m gait speed test (cut point ≤0.8 m/s). RESULTS: Of six participants, none were identified as "at risk" for sarcopenia based on SARC-F scores. Two participants were severely sarcopenic based on EWGSOP2 criteria (had low muscle strength, mass, and physical performance), and five participants were sarcopenic based on muscle mass only. DISCUSSION: Ovarian cancer patients with low muscle mass during neoadjuvant chemotherapy may not be identified as sarcopenic based on the EWGSOP2 diagnostic algorithm. While lacking a universally accepted definition for cancer-related sarcopenia and cancer-specific recommendations for the screening, diagnosis, and treatment of sarcopenia, ovarian cancer clinicians should focus on the diagnosis and treatment of low muscle mass and density.

Unleashing anti-tumour immunity: dietary restriction and exercise interventions adjunct to chemotherapy for cancer patients.

Conventional chemotherapies can stimulate the immune system by increasing tumour antigenicity (e.g., neoantigen exposure to immune cells) and altering adjuvanticity in the tumour (e.g., danger associated molecular patterns and cytokines). These molecules promote the recruitment, activation, and maturation of dendritic cells, which in turn, prime and activate cytotoxic T cells against tumour cells. However, several factors can decrease the immunostimulatory efficacy of chemotherapeutic agents. These include reduced tumour cell antigenicity and adjuvanticity and compromised immune function at a local and systemic level. Findings from preclinical studies show that dietary restriction and exercise promote systemic changes that may help to restore immune system function through several mechanisms, including an enhanced infiltration and function of antitumoral immune cells and a decrease in immunosuppressive cells, leading to a reduction in tumour volume. In addition, dietary restriction and exercise training in mice have been shown to enhance the efficacy of chemotherapy. In human studies there is also emerging evidence that dietary restriction and exercise can impact the immune system towards a more antitumoral profile. In this review, we discuss the immunostimulatory effects of dietary restriction (caloric restriction and fasting) and exercise training in preclinical cancer models, and potential synergies with chemotherapy. We then review clinical studies assessing the effects of these interventions on immune-related endpoints and tumour responses. Finally, we propose that combining dietary restriction with exercise could be a promising strategy to increase chemotherapy efficacy.

Early therapeutic drug monitoring helps to identify inflammatory bowel disease patients with a high risk to fail thiopurine treatment.

AIMS: Conventional thiopurines (azathioprine and mercaptopurine) remain standard therapy to maintain steroid sparing remission in inflammatory bowel disease (IBD), but are regularly discontinued due to adverse drug reactions (ADRs). Measurement of the metabolites 6-thioguanine nucleotides (6-TGN), 6-methylmercaptopurine ribonucleotides (6-MMPR) and the 6-MMPR/6-TGN ratio, may predict the development of these ADRs. Our aim was to evaluate whether early thiopurine metabolite measurements were associated with clinical outcomes. METHODS: A post-hoc analysis was conducted of a multicentre, prospective, observational study on thiopurine-induced hepatotoxicity. IBD patients who initiated thiopurine therapy were included and thiopurine metabolite concentrations were assessed after 7 days (±1) (T1). Patients were monitored for 12 weeks to document the occurrence of ADRs, early treatment discontinuation and effectiveness. RESULTS: In total, 181 patients were evaluated. At T1, 6-MMPR concentrations and 6-TGN/6-MMPR ratios were independently related to treatment discontinuation within 12 weeks after correction for sex, age and body mass index (BMI) (P = .034 and .002, respectively). The largest effects were observed for 6-MMPR ≥3000 pmol/8 × 108 RBC and 6-TGN/6-MMPR ratio ≥17. Furthermore, 6-MMPR concentrations and 6-TGN/6-MMPR ratios at T1 were independently related to skewed metabolism at steady state (Week 8, 6-MMPR/-6TGN ratio ≥11 and ≥20) (both P < .001). The occurrence of ADRs and effectiveness were not independently related to T1 thiopurine metabolite concentrations. CONCLUSIONS: Thiopurine metabolite concentrations at T1 were related to early treatment discontinuation and skewed metabolism at steady state, but not to effectiveness, helping to identify patients with a high risk of thiopurine treatment failure.