108 research outputs found
Pegylated lipid nanocapsules with improved drug encapsulation and controlled release properties
Drugs with poor lipid and water solubility are some of the most challenging to formulate in nanocarriers, typically resulting in low encapsulation efficiencies and uncontrolled release profiles. PEGylated nano- capsules (PEG-NC) are known for their amenability to diverse modifications that allow the formation of domains with different physicochemical properties, an interesting feature to address a drug encapsulation problem. We explored this problem by encapsulating in PEG-NC the promising anticancer drug candidate F10320GD1, used herein as a model for compounds with such characteristics. The nanocarriers were pre- pared from Miglyol®, lecithin and PEG-sterate through a solvent displacement technique. The resulting system was a homogeneous suspension of particles with size around 200 nm. F10320GD1 encapsulation was found to be very poor (<15%) if PEG-NC were prepared using water as continuous phase; but we were able to improve this value to 85% by fixing the pH of the continuous phase to 9. Interestingly, this modification also improved the controlled release properties and the chemical stability of the formulation during storage. These differences in pharmaceutical properties together with physicochemical data sug- gest that the pH of the continuous phase used for PEG-NC preparation can modify drug allocation, from the external shell towards the inner lipid core of the nanocapsules. Finally, we tested the bioactivity of the drug-loaded PEG-NC in several tumor cell lines, and also in endothelial cells. The results indicated that drug encapsulation led to an improvement on drug cytotoxicity in tumor cells, but not in non-tumor en- dothelial cells. Altogether, the data confirms that PEG-NC show adequate delivery properties for F10320GD1, and underlines its possible utility as an anticancer therapy.The authors would like to acknowledge financial support from CENIT-NANOFAR XS53 project, FAES Farma S.A. (Spain), Xunta de Galicia (Competitive Reference Ref. GRC2014/043, FEDER Funds) and the European Commission FP7 EraNet — EuroNanoMed Program-Instituto Carlos III (Lymphotarg pro- yect, Ref. PS09/02670). MGF was a recipient of an Isidro Parga Pondal contract
EP05.02-003 Durvalumab after Chemoradiotherapy (CRT) in Unresectable Stage III NSCLC. Comparative Study of Two Cohorts in the Real-World Setting
[EN] Introduction: Durvalumab is the new standard of care for unresectable
locally advanced NSCLC, with PD-L1 _1% and who did not
have progression after CRT treatment in the European Union. Our
study compares the effectiveness and the frequency of radiation
pneumonitis in patients treated with concurrent CRT with or without
durvalumab consolidation during the same period in real clinical
practice. Methods: A single-center retrospective study. 71 treated
patients with unresectable stage III NSCLC were included between
March 2018 and December 2021, 37 with CRT followed by durvalumab
and 34 with CRT alone. Real-world progression-free survival
(rwPFS) and real-world overall survival (rwOS) were calculated since
the date of the end CRT. Propensity score matching (PSM) 1:1 was
used to account for differences in baseline characteristics. Results:
Median age was 67 years (range 46-82). 25.4% of the patients were
_75 years old. 78.9% were men and 53.5% former smokers. 54.9%
had squamous histology and 28%, 51% and 21% stage IIIA, IIIB and
IIIC disease, respectively. The most used scheme was carboplatinpaclitaxel
(43.7%), receiving induction chemotherapy in up to 54.9%
of patients. 73.2% received between 60-66 Gy doses of radiotherapy.
Median time from end of CRT to onset durvalumab was 44 days
(range 13-120) with a median of 14 infusions (range 6-27). Of the
34 patients without durvalumab treatment, the expression PD-L1
<1% (58.8%) was the most frequent cause for rejecting consolidation
therapy. After PSM analysis, patients distributions were well
balanced. With a median follow-up of 19.7 months (range 1.4-36.6);
median rw-PFS was 9.3 months (95% CI, 5-13.5) without durvalumab
and 17 months (95% CI, 11-22.9) with durvalumab (p¼0.013).
Median rw-OS was 19.3 months (95% CI, 3.8-34.8) without durvalumab
and 29.9 months (95% CI, 23.3-36.6) with durvalumab
(p¼0.241) with a rw-OS% at 6, 18 and 24 months of 90%, 62% and
49% vs 100%, 86% and 74%, respectively. The rate of radiation
pneumonitis was more frequent with durvalumab consolidation
(56.8% against 44.1%), (p¼0.346), especially within 3 months after
CRT. G3 pneumonitis was only observed in the consolidation therapy.
Conclusions: Our results demonstrate the effectiveness of
durvalumab consolidation after CRT in real-world patients with
unresectable stage III NSCLC. Further sample and longer follow-up
are required to obtain more accurate results. Active surveillance and
appropriate management for radiation pneumonitis are needed, in
especially in candidates for consolidation treatmentS
EP05.02-002 Who Benefits More of Durvalumab after Chemoradiotherapy (CRT) in Real-World Patients with Locally Advanced Non-Small-Cell Lung Cancer (NSCLC)?
[EN] Introduction: Durvalumab received EMA approval as consolidation
therapy (CT) for unresectable stage III NSCLC with PD-L1 _1% and
who did not have progression after CRT. Our objective was to analyze
in real clinical practice the effectiveness of durvalumab and explore the
clinical factors that may be associated with the benefit from CT.
Methods: Retrospective study was made at Hospital of Leon (Spain),
including 37 patients with locally advanced NSCLC treated with durvalumab
after CRT treatment between March 2018 and october 2021
(40.5% patients were included in the durvalumab early access program).
The neutrophil-to-lymphocyte ratio (NLR) could identified after
CRT as a factor that may be benefit from durvalumab. Results: Median
age was 67 years (range 46-82 years). 40.5% of patients were _70
years old. 78.4% were male and 51.4% smokers. 54% had non-squamous
histology. PD-L1 expression was <1% in 5% and not available in
8% patients. 2.7% ROS1 rearrangements, 5.4% KRAS mutations and
not available in 43.2% patients. Stage IIIA, IIIB, IIIC disease were
24.3%, 54.1% and 21.6%, respectively. Median time from end of CRT to
onset durvalumab was 44 days (range 13-120 days). Overall median CT
duration was 214.8 days (range 69-399 days) with a median of 14
infusions (range 6-27 infusions). With a median follow up of 19.7
months (range 1.4-34.9 months); 67.6% had stopped CT: 37.8% due to
completing treatment, 16.2% disease progression, 10.8% adverse event
and 2.7% due to COVID19 infection. Median real-world progressionfree
survival (rwPFS) was 17 months (95% CI, 11-23). Median realworld
overall survival (rwOS) was 29.9 months (95% CI, 23.3-36.6). %
rwOS at 6, 18 and 24 months were 100%, 86.9% and 74.5%, respectively.
For patients with post-CRT NLR not exceeding the cohort median
value of 6, receipt of durvalumab was associated with an improvement
in rwOS (median not reached vs 25.7 months; p¼0.025). 56.8% patients
had any grade of radiation pneumonitis (median time from CRT
start: 119 days [range 36-241 days]). Of these, 19% patients developed
worsening of radiation pneumonitis with durvalumab. 54,1% developed
immune-mediated toxicity, mostly G1-2 (85.1%). Conclusions:
Our results demonstrate the effectiveness of durvalumab consolidation
in this patients population in a real-life setting. We identified low NLR
after CRT as a potentially predictive factor for the benefit of CT in
locally advanced NSCLC.S
Unveiling the role of plasticity rules in reservoir computing
Reservoir Computing (RC) is an appealing approach in Machine Learning that
combines the high computational capabilities of Recurrent Neural Networks with
a fast and easy training method. Likewise, successful implementation of
neuro-inspired plasticity rules into RC artificial networks has boosted the
performance of the original models. In this manuscript, we analyze the role
that plasticity rules play on the changes that lead to a better performance of
RC. To this end, we implement synaptic and non-synaptic plasticity rules in a
paradigmatic example of RC model: the Echo State Network. Testing on nonlinear
time series prediction tasks, we show evidence that improved performance in all
plastic models are linked to a decrease of the pair-wise correlations in the
reservoir, as well as a significant increase of individual neurons ability to
separate similar inputs in their activity space. Here we provide new insights
on this observed improvement through the study of different stages on the
plastic learning. From the perspective of the reservoir dynamics, optimal
performance is found to occur close to the so-called edge of instability. Our
results also show that it is possible to combine different forms of plasticity
(namely synaptic and non-synaptic rules) to further improve the performance on
prediction tasks, obtaining better results than those achieved with
single-plasticity models
Assessment of the enhancement of PLGA nanoparticle uptake by dendritic cells through the addition of natural receptor ligands and monoclonal antibody
Effect of the ultrastructure of chitosan nanoparticles in colloidal stability, quorum quenching and antibacterial activities
We have fabricated two types of crosslinked chitosan-based nanoparticles (NPs), namely (1) ionically crosslinked with tripolyphosphate (TPP), designated as IC-NPs and (2) dually co-crosslinked (ionically and covalently with TPP and genipin, respectively) termed CC-NPs. The two types of NPs were physichochemically characterized by means of DLS-NIBS, synchrotron SAXS and M3-PALS (zeta potential). First, we found that covalent co-crosslinking of ionically pre-crosslinked nanoparticles yielded monodisperse CC-NPs in the size range of ∼200 nm, whereas the parental IC-NPs remained highly polydisperse. While both types of chitosan nanoparticles displayed a core-shell structure, as determined by synchrotron SAXS, only the structure of CC-NPs remained stable at long incubation times. This enhanced structural robustness of CC-NPs was likely responsible of their superior colloidal stability even in biological medium. Second, we explored the antimicrobial and quorum sensing inhibition activity of both types of nanoparticles. We found that CC-NPs had lower long-term toxicity than IC-NPs. In contrast, sub-lethal doses of IC-NPs consistently displayed higher levels of quorum quenching activity than CC-NPs. Thus, this work underscores the influence of the NP’s ultrastructure on their colloidal and biological properties. While the cellular and molecular mechanisms at play are yet to be fully elucidated, our results broaden the spectrum of use of chitosan-based nanobiomaterialsin the development of antibiotic-free approaches against Gram-negative pathogenic bacteria
Clinical trials to estimate the efficacy of preventive interventions against malaria in paediatric populations: a methodological review
BACKGROUND: Recent years have seen publication of a considerable number of clinical trials of preventive interventions against clinical malaria in children. There has been variability in the specification of end-points, case definitions, analysis methods and reporting and the relative lack of standardization complicates the ability to make comparative evaluations between trials. METHODS: To prepare for a WHO consultation on design issues in malaria vaccine trials, controlled trials of preventive interventions against malaria in children in endemic countries were identified in which clinical malaria, or death, had been one of the main end-points. Trials were included that evaluated the impact of vaccines, insecticide-treated bed nets (ITN), intermittent presumptive or preventive therapy in infants (IPTi) or, in one instance, vitamin A supplementation. Methods that had been used in these trials were summarized and compared in order to identify issues that were directly relevant to the design of malaria vaccine trials. RESULTS: 29 controlled trials of preventive malaria interventions were identified, of which eight were vaccine trials. Vaccine trials that were designed to detect an effect on clinical malaria all reported the incidence rate of first episodes of clinical malaria as their primary endpoint. Only one trial of a preventive intervention (of ITN) was identified that was designed to detect an effect on severe malaria. A group of larger trials were designed to detect an effect of impregnated bed nets or curtains on all-cause mortality as the primary end-point. Key methodological and reporting differences between trials are noted in the text. Two issues have been identified that are of some concern. Firstly, the choice of primary endpoint is not stated in the reports of a number of the trials and, secondly, the relationship between pre-specified analysis plans and trial reports is rarely made clear. CONCLUSION: This article reports an investigation into the ways in which trial design and reporting could be improved and standardized to enable comparative evaluation of the relative merits of malaria control measures, and specifically with respect to the design of malaria vaccine trials. The need for standardization of clinical trial design, conduct, analysis and reporting has been also affirmed as a priority area by the Malaria Vaccine Technology Roadmap
MELCHIORS: The Mercator Library of High Resolution Stellar Spectroscopy
Aims. Over the past decades, libraries of stellar spectra have been used in a large variety of science cases, including as sources of reference spectra for a given object or a given spectral type. Despite the existence of large libraries and the increasing number of projects of large-scale spectral surveys, there is to date only one very high-resolution spectral library offering spectra from a few hundred objects from the southern hemisphere (UVES-POP). We aim to extend the sample, offering a finer coverage of effective temperatures and surface gravity with a uniform collection of spectra obtained in the northern hemisphere.Methods. Between 2010 and 2020, we acquired several thousand echelle spectra of bright stars with the Mercator-HERMES spectrograph located in the Roque de Los Muchachos Observatory in La Palma, whose pipeline offers high-quality data reduction products. We have also developed methods to correct for the instrumental response in order to approach the true shape of the spectral continuum. Additionally, we have devised a normalisation process to provide a homogeneous normalisation of the full spectral range for most of the objects.Results. We present a new spectral library consisting of 3256 spectra covering 2043 stars. It combines high signal-to-noise and high spectral resolution over the entire range of effective temperatures and luminosity classes. The spectra are presented in four versions: raw, corrected from the instrumental response, with and without correction from the atmospheric molecular absorption, and normalised (including the telluric correction)
Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2
The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality
Robust estimation of bacterial cell count from optical density
Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data
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