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Carbon-based acid catalysts functionalized with mesoporous aluminosilicate patches in coexistence with benzyl sulphonic moieties
No full textLignocellulosic biomass is a promising renewable resource for the production of numerous key commodity chemicals, including 5-hydroxymethylfurfural (5-HMF), that can be sourced from its cellulose component via a three-step reaction promoted by both Brønsted and Lewis acid sites [1]. Given the highly oxygenated nature of biomass, carbon-based catalysts are one of the best possible systems for favouring this transformation, thanks to their superior mechanical and chemical resistance in this specific media, along with controlled and tuneable textural and surface features. In the present work, bifunctional carbon-based acid catalysts were successfully synthesized by co-locating mesoporous aluminosilicate patches [2-3] and benzyl sulfonic moieties [4] on the substrate’s surface (activated carbon powder (AC), fraction < 50μm), conferring both Brønsted and Lewis acidity to the same solid. These bifunctional catalysts and their monofunctional equivalents (sulfonated carbon and aluminosilicate patched carbons) were then fully characterized and compared in terms of catalytic activity. SEM/EDX, TEM, and XPS analyses were carried out to investigate the achieved composition and morphology, whereas nitrogen physisorption and Boehm titration were performed to study the attained textural features and acidity, respectively. Finally, the catalytic performance of all the synthesized systems was investigated for the upgrading of cellobiose to 5-HMF. A proximity effect was found when the two acidic sites were combined onto the same substrate, facilitating the overall conversion of the sugars involved in comparison to the designed mixtures of monofunctional solids tested. A maximal yield of 37% of 5-HMF was attained after 23 h with catalyst AC–aluminosilicate/SO3H in a THF:mQ water system at 423 K. No significant traces of side products were observed after 23 hours, indicating the satisfactory selectivity of the catalyst for the targeted sugars
[Comparison of gemcitabine production costs in individualized and standardized doses].
No full textCancer chemotherapy doses are often adapted to patients' body surface area and produced individually. Alternatively, dose-banding promotes batch production of clinically defined fixed doses, for which a standard deviation of±5% determines a band incorporating individual doses calculated on the basis of body surface area. The aim is to compare the costs of individualized and batch production of gemcitabine in a centralized chemotherapy reconstitution unit. The study was carried out using a cost-minimization analysis. The first step was to identify the percentage of gemcitabine preparations eligible for standardization over a one-year period, and to define the standardized doses of clinical interest, taking into account a standard deviation of±5%. The second step was to compare the direct and indirect costs of individualized production with those of mass production. The percentage of standardizable preparations was evaluated at 69.8%, with standardized doses of 1500mg±5%, 1600mg±5%, 1800mg±5%, 2000mg±5% and 2200mg±5%. Comparison of production costs for a total of 324 bags over one year showed that dose-banding reduced costs by 7%. The cost difference between individualized production and batch production of standardized doses of gemcitabine bags is in favor of dose-banding. The analysis could be extended to other anticancer molecules
Efficacy of tazemetostat in combination with R-CHOP in elderly patients newly diagnosed with diffuse large B cell lymphoma: results of the EpiRCHOP phase II study of the LYSA.
No full textIn the phase I Epi-RCHOP study (NCT02889523), we reported that R-CHOP-tazemetostat was well tolerated with the recommended phase II dose, consistent with monotherapy. Phase II included newly diagnosed diffuse large B cell lymphoma patients aged 60-80 years who received six cycles of rituximab-CHOP (R-CHOP) with continuous tazemetostat (800 mg BID), plus two cycles of tazemetostat and rituximab (cycles 7 and 8), from July 31, 2020 to July 18, 2022. Primary endpoint was positron emission tomography complete metabolic response (CMR). Sample size was calculated with H0 of 70% and H1 assumption of 80%. The trial enrolled 122 patients: median age 70 (60-80), 90.2% with stage III-IV, and 73.8% with International Prognostic Index 3-5. Overall, 100 patients (82%) received eight cycles, while 22 had premature treatment discontinuation (PTD), including 12 during the first two cycles. Reasons for PTD were consent withdrawal (N = 10), adverse events (N = 6), death (N = 2), protocol deviation (N = 2), progressive disease (N = 1), and physician decision (N = 1). The median percentage of relative dose intensity of tazemetostat and R-CHOP exceeded 90%, but required a protocol amendment and reduction in vincristine dosage at 1 mg full dose. At the end of treatment or PTD, 92/122 patients (75.4%) achieved CMR, eight (6.6%) partial metabolic response, five (4.1%) progressive disease, two (1.6%) died (septic shock), and 15 (12.3%) were not evaluated. Sensitivity analysis, excluding ten non-evaluated patients who withdrew consent, showed CMR in 82.1%. After a median follow-up of 18.5 months (IQR: 15.4-21), estimated progression-free and overall survival at 18 months were 77.7% (95% CI: 67.5-85.1%) and 88.8% (95% CI: 79.9-93.9%), respectively. R-CHOP plus tazemetostat is feasible with a promising CMR in elderly DLBCL patients. Complementary biomarker studies are needed for a more personalized approach. This study was sponsored under a grant from Ipsen
Primary mediastinal B-cell lymphoma (PMBCL): The LYSA pragmatic guidelines.
No full textPrimary mediastinal B-cell lymphoma (PMBCL) is a distinct subtype of large B-cell lymphoma with unique clinical, histopathological, and molecular characteristics. Despite its aggressive nature, PMBCL has a high cure rate when managed appropriately. Advances in the understanding of PMBCL biological characteristics, coupled with improvements in diagnostic tools and therapeutic approaches, have significantly improved patient outcomes in recent years. In this article, we present a set of pragmatic guidelines developed by the Lymphoma Study Association (LYSA) for the management of PMBCL. These guidelines address key aspects of diagnosis, staging, response evaluation, and treatment, integrating the latest evidence from clinical trials, expert consensus, and real-world practice. The aim of the guidelines is to provide clinicians with a clear, practical framework to optimize care for patients with PMBCL, ensuring that the best available evidence is translated into clinical practice
Can Personalized Transcranial Alternating Current Stimulation (tACS) Modulate Pain Perception and Pain-related Oscillations?
No full textOngoing neural oscillatory activity was suggested to play a crucial role in the experience of pain. This study aims to determine whether there is a causal link between neural oscillations and pain perception, and whether transcranial alternating current stimulation (tACS) can modulate it. We employed tACS to modulate ongoing oscillatory activities measured using scalp electroencephalography (EEG), and investigated how this affects pain perception. To induce pain, we used sustained periodic 0.2 Hz thermonociceptive stimuli. tACS targeted M1, contralateral to the side of the thermonociceptive stimulation. The frequency of stimulation was set to the individual peak alpha frequency (PAF). A sham stimulation was used as a control condition. Data was acquired from 38 healthy volunteers. Statistical tests were performed using linear mixed models using “time” (pre vs post) and “condition” (active vs sham) as factors. In the “post” phase, we observed a significant reduction in heat pain thresholds (HPTs) and an increase in both intensity and pain perception compared to the “pre” phase, regardless of condition (p<0.01). The HPT reduction was greater for the sham condition compared to the active condition, although not significantly. Furthermore, both local and global average PAF values decreased significantly (p<0.01) in the two conditions, with a slightly greater reduction in the sham condition. The reduction of HPTs, along with the increases in the intensity of perception and pain over time, suggest that participants may have become sensitized to the thermonociceptive stimulation. Although the current study does not show a significant effect of tACS on perception, the small but consistent trend of lower pain perception and smaller PAF changes in the active condition compared to sham may be interpreted as a reduced sensitization following tACS, highlighting the potential for further exploration of tACS effects on pain with enhanced designs and strategies
Transcriptomic responses of alveolar macrophages under PSLT particle overload : influence of species and particle characteristics
No full textChronic inhalation of poorly soluble low toxicity (PSLT) particles like titanium dioxide (e.g. P25) or carbon black (e.g. Printex 90) at high doses leading to lung overload, can induce chronic inflammation and lung cancer in rats. However, the relevance of these findings to humans and other PSLT particles remains debated. To address this, we examined gene expression profiles of rat and human alveolar macrophages exposed in vitro to P25 and Printex 90 particle overload. While rat cells were more responsive, both species showed a unique transcriptomic profile in response to P25 and Printex 90. An additional profile was identified in human cells exposed to Printex 90. We also examined rat macrophage responses to P25 and pigment grades TiO2 particles. Particles with higher specific surface areas (P25) had increased reactivity to overload. Our findings highlight the roles of species differences and physicochemical particle characteristics in modulating the responses to PSLT particle overload.(BIFA - Sciences biomédicales et pharmaceutiques) -- UCL, 202
Geriatric assessment in Belgian nursing homes: qualitative insights
No full textBackground Nursing home residents (NHR) have complex health needs due to their multimorbidity and frailty, challenging interorganisational collaboration, particularly between nursing homes (NH) and hospitals. Coronavirus disease pandemic highlighted the need to strengthen the expertise of NHs care teams. Geriatric mobile teams (GMT) exist in several countries and aim to provide interdisciplinary advice to reinforce the primary care expertise. To develop GMTs in Belgium, we chose a participatory and systemic approach. The aim focuses on identifying areas of partnership between hospitals and NHs based on the geriatric needs of residents, from the perspective of the stakeholders involved in their care. Additionally, it examines the essential requirements for fostering collaboration among these stakeholders. Method Qualitative study using semi-structured interviews of 20 healthcare professionals working in a Belgian academic hospital or within its affiliated NH network. Themes were extracted using thematic analysis, employing simultaneously an inductive approach for the partnership areas and a deductive approach constructed around Karam‘s framework of interorganizational and interprofessional collaboration. Results Participants highlighted the increasing complexity of NHRs’ healthcare needs and the crucial role of geriatric expertise in managing behavioural and psychological symptoms of dementia, assessing complex medical situations, and advance care planning. While all supported enhanced collaboration, key challenges included formalizing processes and facilitating care integration between providers. Balancing high-level care with the risk of overmedicalization also remains a critical issue. These findings are reflected in three main themes: empowering nursing homes with geriatric expertise; The high importance of integration and formalisation; and balancing tension between a place of residence and high skilled care. Conclusion This study provides a comprehensive overview of expected collaboration areas and practical strategies to manage constraints. By using a qualitative approach, we integrated the perspectives of all key stakeholders, ensuring that proposed initiatives align with actual needs. Strengthening collaboration between NHs and geriatric services requires formalized frameworks and co-designed protocols with frontline caregivers. Such an initiative has the potential to dismantle compartmentalized care pathways for NHRs
Natural pozzolan as a novel heterogeneous catalyst for the synthesis of alkylaminophenols
No full textThe development of sustainable catalysts from natural materials, such as pozzolan, represents a promising strategy in green chemistry. The pozzolan studied was subjected to multi-technique characterization (XRD, FTIR, BET, and SEM) to establish its structural and textural properties. The results obtained highlight the effectiveness of this material as a catalyst for the Petasis reaction, allowing the synthesis of a diversity of alkylaminophenols with yields reaching 93%. The reaction was successfully carried out on a gram scale, confirming the potential of pozzolan as a heterogeneous catalyst. This catalyst, which is recyclable and inexpensive, represents an attractive alternative for large-scale applications while respecting the environment
Les journaux des apprentissages : vers des pratiques langagières écrites et orales plus égalitaires
No full textRadiation Degradation and Mitigation of an Ultrathin SOI SPAD Using a Perimeter Gate
No full textThis work investigates the robustness of an ultrathin backside-illuminated (BSI) silicon-on-insulator (SOI) single-photon avalanche diode (SPAD) against gamma-ray irradiation for space applications. Experimental results demonstrate a breakdown voltage shift in the studied SPAD from 10.17 to 9.95 V after a total ionizing dose (TID) of 132 krad(Si). An increase in dark count rate (DCR) from 1490 to 2700 cps/ μ m2 at 1 V excess bias is shown at this dose. TCAD simulations explain the role of the oxide-trapped charges, induced by irradiation in the insulating layer surrounding the active region, on the SPAD performance. These trapped charges shift the peak electric field, leading to premature breakdown while the extension of the active area affected by impact ionization increases the DCR. Further simulations show that implementing a perimeter-gated structure and reducing oxide thickness can effectively mitigate these effects by leveraging capacitive effects, preventing a breakdown voltage shift. The perimeter gate (PG) lowers the simulated DCR after irradiation from 2700 to 1365 cps/ μ m2, thereby enhancing the radiation resilience of ultrathin SOI SPADs beyond a TID of 132 krad(Si)