Last twenty-years activity of cardiovascular tissue banking in Barcelona

The Barcelona Tissue Bank was established from the merge of two previous multi-tissue banks. Potential donors are screened by Donor Center staff and multi-tissue retrieval is performed by specialized own teams. Tissue processing and preservation is performed in clean room facilities by specialised personnel. After quality control of both donor and all tissues results, the heart valves and vascular segments are stored until medical request. The aim of this report is to present the cardiovascular tissue activity and retrospectively evaluate the outcomes of the changes performed in last 20 years. Cardiovascular tissue from 4088 donors was received, specifically 3115 hearts and 2095 vascular segments were processed and evaluated. A total of 48% of the aortic valves, 68% of the pulmonary valves and 75% of the vascular segments were suitable for transplant. The main reason for discarding tissue was macroscopic morphology followed by microbiological results, for both valves and arteries. Altogether, 4360 tissues were distributed for transplantation: 2032 (47%) vascular segments, 1545 (35%) pulmonary valves and 781 (18%) aortic valves. The most common indication for aortic valve surgery was the treatment of endocarditis, while for pulmonary valves, it was congenital malformation reconstruction. Vascular segments were mainly used for reconstruction after ischemia. During this period, a number of changes were made with the goal of enhancing tissue quality, safety and efficacy. These improvements were achieved through the use of a new antibiotic cocktail, increasing of donor age criteria and changing the microbiological control strategy.

Mancha3D Code: Multipurpose Advanced Nonideal MHD Code for High-Resolution Simulations in Astrophysics

The Mancha3D code is a versatile tool for numerical simulations of magnetohydrodynamic (MHD) processes in solar/stellar atmospheres. The code includes nonideal physics derived from plasma partial ionization, a realistic equation of state and radiative transfer, which allows performing high-quality realistic simulations of magnetoconvection, as well as idealized simulations of particular processes, such as wave propagation, instabilities or energetic events. The paper summarizes the equations and methods used in the Mancha3D (Multifluid (-purpose -physics -dimensional) Advanced Non-ideal MHD Code for High resolution simulations in Astrophysics 3D) code. It also describes its numerical stability and parallel performance and efficiency. The code is based on a finite difference discretization and a memory-saving Runge-Kutta (RK) scheme. It handles nonideal effects through super-time-stepping and Hall diffusion schemes, and takes into account thermal conduction by solving an additional hyperbolic equation for the heat flux. The code is easily configurable to perform different kinds of simulations. Several examples of the code usage are given. It is demonstrated that splitting variables into equilibrium and perturbation parts is essential for simulations of wave propagation in a static background. A perfectly matched layer (PML) boundary condition built into the code greatly facilitates a nonreflective open boundary implementation. Spatial filtering is an important numerical remedy to eliminate grid-size perturbations enhancing the code stability. Parallel performance analysis reveals that the code is strongly memory bound, which is a natural consequence of the numerical techniques used, such as split variables and PML boundary conditions. Both strong and weak scalings show adequate performance up to several thousands of processors (CPUs).

Exchangeable Self-Assembled Lanthanide Antennas for PLIM Microscopy

Lanthanides have unique photoluminescence (PL) emission properties, including very long PL lifetimes. This makes them ideal for biological imaging applications, especially using PL lifetime imaging microscopy (PLIM). PLIM is an inherently multidimensional technique with exceptional advantages for quantitative biological imaging. Unfortunately, due to the required prolonged acquisitions times, photobleaching of lanthanide PL emission currently constitutes one of the main drawbacks of PLIM. In this study, we report a small aqueous-soluble, lanthanide antenna, 8-methoxy-2-oxo-1,2,4,5-tetrahydrocyclopenta[de]quinoline-3-phosphonic acid, PAnt, specifically designed to dynamically interact with lanthanide ions, serving as exchangeable dye aimed at mitigating photobleaching in PLIM microscopy in cellulo. Thus, self-assembled lanthanide complexes that may be photobleached during image acquisition are continuously replenished by intact lanthanide antennas from a large reservoir. Remarkably, our self-assembled lanthanide complex clearly demonstrated a significant reduction of PL photobleaching when compared to well-established lanthanide cryptates, used for bioimaging. This concept of exchangeable lanthanide antennas opens new possibilities for quantitative PLIM bioimaging.

Radiotherapy for Metastatic Spinal Cord Compression with Increased Doses: Final Results of the RAMSES-01 Trial

PURPOSE/OBJECTIVE(S)

To investigate the outcomes of precision-radiotherapy (RT) with 15 × 2.633 Gy (EQD2 = 41.6 Gy for tumor cell kill, α/β = 10 Gy) or 18 × 2.333 Gy (EQD2 = 43.2 Gy) in patients with metastatic spinal cord compression (MSCC) and favorable survival prognoses (>35 points on a validated survival score). In addition, these patients were compared to a historical control group of patients with favorable prognoses treated with 10 × 3 Gy (EQD2 = 32.5 Gy).

MATERIALS/METHODS

In a multi-center phase 2 study (RAMSES-01), patients with MSCC and favorable survival prognoses receiving 15 × 2.633 Gy or 18 × 2.333 Gy of precision-RT alone (no upfront surgery) were mainly evaluated for local progression-free survival (LPFS), defined as no deterioration of motor function during RT and no in-field recurrence of MSCC following RT, at 12 months (primary endpoint). Secondary endpoints included improvement of motor and sensory functions, post-RT ambulatory status, relief of pain and distress, toxicity, and survival (OS). The maximum relative doses allowed to the spinal cord were 101.5 % of the prescribed dose for 18 × 2.333 Gy and 101.2% for 15 × 2.633 Gy, respectively (both representing an EQD2 of 46.6 Gy for myelopathy, α/β = 2 Gy). In addition, the RAMSES-cohort was compared to a historical control group (N = 266) irradiated with 10 × 3 Gy (propensity score adjusted Cox regression).

RESULTS

In the RAMSES-cohort, 50 (of 62 planned) patients were evaluable for LPFS and included in the analyses. Since OS was worse than expected, a new survival score was developed, which was more precise in predicting OS than a previous tool. As a consequence, the RAMSES-trial, which was based on the previous score, was terminated. In the 50 patients included so far, 12-month rates of LPFS and OS were 97.6% and 69.9%, respectively. Improvement of motor function occurred in 28 patients (56.0%), and 47 patients (94.0%) were ambulatory following RT. Within 3 months following RT, 12 of 21 patients (57.2%) with pre-RT sensory deficits improved, 38 of 45 patients (84.4%) with pre-RT pain experienced at least partial relief, and 39 of 50 patients (78.0%) reported relief of distress. Ten of 50 patients (20.0%) experienced grade 2 toxicities (mainly esophagitis/dysphagia) and another two patients (4.0%) grade 3 toxicities (1 diarrhea, 1 esophagitis). After propensity score adjustment, the RAMSES-cohort showed significantly better LPFS than the control group (hazard ratio = 0.125, 95% confidence interval = 0.016 - 0.962, p = 0.046) and a strong trend regarding improvement of motor function (hazard ratio = 1.943, 95% confidence interval = 0.981 - 3.850, p = 0.057). Post-RT ambulatory rates (p = 0.56) and OS rates (p = 0.62) were not significantly different.

CONCLUSION

Precision-RT with 15 × 2.633 Gy or 18 × 2.333 Gy was sufficiently well tolerated and resulted in significantly better long-term LPFS than 10 × 3 Gy in patients with MSCC and favorable survival prognoses. Thus, the dose-fractionation regimens of the RAMSES-01 trial appear preferable for these patients.

Exceptional Electron-Rich Heteroaromatic Pentacycle for Ultralow Band Gap Conjugated Polymers and Photothermal Therapy

Stable redox-active conjugated molecules with exceptional electron-donating abilities are key components for the design and synthesis of ultralow band gap conjugated polymers. While hallmark electron-rich examples such as pentacene derivatives have been thoroughly explored, their poor air stability has hampered their broad incorporation into conjugated polymers for practical applications. Herein, we describe the synthesis of the electron-rich, fused pentacyclic pyrazino[2,3-b:5,6-b']diindolizine (PDIz) motif and detail its optical and redox behavior. The PDIz ring system exhibits a lower oxidation potential and a reduced optical band gap than the isoelectronic pentacene while retaining greater air stability in both solution and the solid state. The enhanced stability and electron density, together with readily installed solubilizing groups and polymerization handles, allow for the use of the PDIz motif in the synthesis of a series of conjugated polymers with band gaps as small as 0.71 eV. The tunable absorbance throughout the biologically relevant near-infrared I and II regions enables the use of these PDIz-based polymers as efficient photothermal therapeutic reagents for laser ablation of cancer cells.

Excited-State Intramolecular Proton Transfer in 2-(2'-Hydroxyphenyl)pyrimidines: Synthesis, Optical Properties, and Theoretical Studies

The development of fluorescence materials with switched on/off emission has attracted great attention owing to the potential application of these materials in chemical sensing. In this work, the photophysical properties of a series of original 2-(2'-hydroxyphenyl)pyrimidines were thoroughly studied. The compounds were prepared by following well-established and straightforward methodologies and showed very little or null photoluminescence both in solution and in the solid state. This absence of emission can be explained by a fast proton transfer from the OH group to the nitrogen atoms of the pyrimidine ring to yield an excited tautomer that deactivates through a nonradiative pathway. The key role of the OH group in the emission quenching was demonstrated by the preparation of 2'-unsubstituted derivatives, all of which exhibited violet or blue luminescence. Single crystals of some compounds suitable for an X-ray diffraction analysis could be obtained, which permitted us to investigate inter- and intramolecular interactions and molecular packing structures. The protonation of the pyrimidine ring by an addition of trifluoroacetic acid inhibited the excited-state intramolecular proton transfer (ESIPT) process, causing a reversible switch on fluorescence response detectable by the naked eye. This acidochromic behavior allows 2-(2'-hydroxyphenyl)pyrimidines to be used as solid-state acid-base vapor sensors and anticounterfeiting agents. Extensive density functional theory and its time-dependent counterpart calculations at the M06-2X/6-31+G** level of theory were performed to rationalize all the experimental results and understand the impact of protonation on the different optical transitions.

Changes of CD3+CD56+ γδ T cell number and apoptosis during hospital admission are related to mortality in septic patients

Immunoparalysis and apoptosis of T cells are serious problems for the evolution of septic patients. We aimed to relate changes in the number of αβ and γδ T cells during hospital stay to the poor evolution of sepsis. In this prospective study, we recruited a total of 92 septic patients from the Emergency and Intensive Care Departments of two Hospitals, according to the latest criteria for the definition and management of sepsis. According to the severity of the septic process, there was a progressive decrease in T cells, being much more intense in γδ T cells. This decrease recovered in surviving patients, but CD3+CD56+ γδ T cells continued to decreased during hospital stay in non-surviving patients. Apoptosis increased in sepsis. Cell death of CD3+CD56+ γδ T cells progressively increased according to the severity of sepsis, especially in non-surviving patients.

Reversal of a Fluorescent Fluoride Chemosensor from Turn-Off to Turn-On Based on Aggregation Induced Emission Properties

Here we present a new approach for the development of fluoride chemosensors taking advantage of aggregation induced emission (AIE) properties. Although AIE-based chemosensors have been described, they rely primarily on the analyte causing aggregation and hence fluorescence. We propose a new concept in the use of AIE for the development of fluorescent sensors. Our hypothesis is based on the fact that a turn-off chemosensor in solution can be transformed into turn-on in the solid state if the properties of ACQ and AIE are properly combined between the fluorescent molecules involved. To demonstrate this hypothesis, we have selected a fluorescent chemosensor for the fluoride anion with a conjugated structure of bis(styryl)pyrimidine that, while showing turn-off behavior in solution, becomes turn-on when it is brought to the solid state. We have also combined it with the advantages of a detection system based on the microfluidic paper-based analytical devices (μPAD). The system is fully characterized spectroscopically both in solution and in the solid state, and quantum mechanical calculations were performed to explain how the sensor works. The prepared device presents a high sensitivity, with no interference and with an LoD and LoQ that allow determination of fluoride concentrations in water 2 orders of magnitude below the maximum allowed by WHO.

Dynamic Excimer (DYNEX) Imaging of Lipid Droplets

Unraveling cellular physiological processes via luminescent probes that target specific cellular microenvironments is quite challenging due to the uneven distribution of probes. Herein, we designed a new dynamic excimer (DYNEX) imaging method that involves the sensitive detection of nanosecond-scale dynamic molecular contacts of a fluorescent acridone derivative and reveals the cell microenvironment polarity. Using our method, we specifically tracked cell lipid droplets in fibroblast colon carcinoma cells. These organelles play a central role in metabolic pathways, acting as energy reservoirs in regulatory processes. DYNEX imaging provides the inner polarity of cell lipid droplets, which can be related to lipid contents and metabolic dysfunctions. This new methodology will inspire development of novel multidimensional fluorescent sensors that are able to provide target-specific and orthogonal information at the nanosecond scale.

Evaluation of adverse outcomes in patients with Troponinemia without significant coronary artery disease; a proposal application of the ACTION-ICU Score

Purpose

Elevated troponin in absence of significant coronary artery disease is a frequent situation that is associated with increased mortality. Criteria to estimate complications in these patients are not defined. The aim of this study was to evaluate the predictive capacity of the ACTION-ICU score, a scale designed to predict likelihood of complication requiring ICU care for patients with NSTEMI, to define risk of complications in patients with elevated troponin without significant coronary artery disease.

Methods

A retrospective study of patients with elevated troponin and no significant coronary artery disease were selected to apply the ACTION-ICU Score to predict likelihood of complications. Complications were defined as cardiac arrest development, shock, high-grade atrioventricular block, respiratory failure, stroke, or death during the index hospitalization. ROC Curves were created to determine the predictive power.

Results

1221 patients were screened, of them 181 presented elevated troponin without significant coronary artery disease; age median 65 year (IQR 56–75 years), female 48,1%. Of 181 patients, 73.5% were admitted to ICU based on physician criteria. Only 13.3% of patients presented a complication. A score greater than 5 was present in 33.7% of the patients, of which 5,5% presented a complication. ROC to predict complications was 0,75 (95% CI: 0,65–0,86). Best cut off point was >6 points, sensitivity 70.83%, specificity 72.08%, LR+ 2.54, LR− 0.4.

Conclusions

In patients with elevated troponin and no significant coronary artery disease, the ACTION-ICU Score was a predictive scale for the development of complications with adequate accuracy. The best cut-off point for this classification in patients with elevated troponin in absence of significant coronary artery disease was >6.

Funding Acknowledgement

Type of funding sources: None. ROC Curve of ACTION-ICU score >6 points

Histological and molecular characterization of human aortic stenosis: a matter of sex

Introduction

Aortic stenosis (AS) is the most common heart valve disease and it is strongly prevalent with elderly. AS is a progressive, degenerative disease associated with fibrosis and calcification of the valve leaflets. Surgical valve replacement is the only treatment available. Molecular, cellular and interstitial events activate multifactorial and complex cues with a significant contribution by valve interstitial cells (VICs). Despite male sex is a risk factor for developing AS, there is scant information on sex-specific differences in aortic valve (AV) biology or pathology.

Purpose

The aim of our study was to analyse sex-specific differences in aortic valves from AS patients.

Methods

185 patients with severe AS undergoing surgical valve replacement were recruited. 149 AVs (66 women; 83 men) were used for ex vivo analyses. Human VICs were isolated from 36 AVs (12 women; 24 men) for in vitro experiments. AVs structure were evaluated by haematoxylin-eosin, Movat, Alizarin Red, Congo red and Alcian blue/Sirius Red staining and immunohistochemistry. Western blot, ELISA and zymography were used for molecular biology studies.

Results

AVs from men presented increased inflammatory infiltrates (CD68 and CD45 positive cells) as compared to women. Complementarily, AVs from men exhibited higher levels of the inflammatory molecules interleukin (IL)-6 and IL-1b and RANTES. In line with these results, oxidative stress markers (eNOS, myeloperoxidase, malondialdehyde and nitrotyrosine) were upregulated in male AVs. Concerning, fibrosis, increased levels of collagen type I, fibronectin and syndecan-1 were found in AVs from men. Extracellular matrix (ECM) remodelling was characterized by reduced metalloproteinase-1 expression and increased tissue inhibitor of metalloproteinase-2 expression in male AVs. Importantly, calcification and osteogenic markers (bone morphogenetic protein-9, periostin, osteocalcin and Sox-9) was greatly enhanced in men AVs as compared to women. These findings were confirmed in isolated VICs. At baseline, male VICs presented higher myofibroblast-like phenotype than female VICs. In line with our ex vivo results, male VICs exhibited increased inflammatory, oxidative stress, fibrotic and osteogenic differentiation markers.

Conclusions

Our results suggest that the mechanisms driving the AV pathogenesis could be different in men and women patients with the same AS severity. Male AVs and isolated VICs presented more inflammation, oxidative stress, fibrosis and ECM remodelling including extensive calcification as compared to female. A better knowledge of the pathophysiological pathways in AVs and VICs will allow developing sex-specific options for AS treatment.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Instituto de Salud Carlos III

P–787 Impact of delaying ART to promote weight loss: a large multicentre study accounting for the combined effect of female/male age and body mass index (BMI)

Study question

Is postponing the start of ART (to promote a reduction in female BMI) beneficial for cumulative live birth rates (CLBR) when accounting for the female/male ageing this delay will cause?

Summary answer

Postponing ART treatment in one year to promote female weight loss could be detrimental in women of advanced maternal age (AMA, >35 years-old).

What is known already

Overweight/obese couples are frequently encouraged to lose weight prior to infertility treatment to enhance ART outcomes. However, a meaningful weight loss is often difficult to achieve for these couples, frequently taking at least one year to accomplish. Given that both female and male ageing are also important for ART success, we were interested in understanding the combined impact on CLBR of BMI reduction and ageing following a one-year delay.

Study design, size, duration

A retrospective study including patients performing their first ART cycle using autologous gametes between 2013–2018 in one of 39 participating ART centres. Only GnRH antagonist cycles were included (n = 14260). CLBR was the primary outcome. Secondary outcomes included time-to-pregnancy, birthweight and gestational age.

Participants/materials, setting, methods

Patients were subdivided according to female BMI (Kg/m2) in either underweight (<18.5), normal-weight (18.5–24.9), overweight (BMI 25.0–29.9 kg/m2) and obese (≥30 kg/m2). Meaningful and extreme weight loss were defined as a reduction from obesity to either overweight or normal-weight, respectively. We performed multivariable regression analysis to account for potential confounding.

Main results and the role of chance

Overweight (36.8%) and obese (33.0%) women had significantly lower CLBR when compared to the underweight (42.6%) and normal-weight (41.4%). When assessing the confounder-adjusted net-effect of male/female age and BMI, the predicted benefit of promoting a meaningful BMI reduction was lower than the estimated hindrance due to male/female ageing as soon as women reached AMA (n = 8365, 58.6%). This absence of benefit was especially important in women >38 years-old, in which even extreme weight-loss did not compensate for the age-related reduction in CLBR caused by the one-year delay. Moreover, male weight-loss failed to provide any additional benefit when accounted for in the regression models. Finally, obesity was also associated with a modest but statistically significant one-month delay in time-to-pregnancy and a 96.1 g (95% confidence interval: 39.9–152.4) increase in birth weight. The diagram of predicted outcomes presented in this study may serve as a useful tool to counsel patients before treatment, namely when recommending treatment postponement to promote short-term (i.e. 3–6 months) or long-term (i.e. 1 year) weight loss.

Limitations, reasons for caution

Caution is recommended when extrapolating these results into everyday practice owing to the retrospective nature of the study and the fact that only GnRH antagonist cycles were included.

Wider implications of the findings: Patients are frequently confronted with the dilemma to either postpone treatment (and promote weight loss) or start treatment immediately (to avoid further ageing). Our results seem to show that women in AMA may have hindered CLBR if recommended to delay treatment even if the desired weight loss is ultimately achieved.

Trial registration number

Not applicable

Wastewater effluents cause microbial community shifts and change trophic status

Widespread wastewater pollution is one of the greatest challenges threatening the sustainable management of rivers globally. Understanding microbial responses to gradients in environmental stressors, such as wastewater pollution, is crucial to identify thresholds of community change and to develop management strategies that protect ecosystem integrity. This study used multiple lines of empirical evidence, including a novel combination of microbial ecotoxicology methods in the laboratory and field to link pressure-stressor-response relationships. Specifically, community-based whole effluent toxicity (WET) testing and environmental genomics were integrated to determine real-world community interactions, shifts and functional change in response to wastewater pollution. Here we show that wastewater effluents above moderate (>10%) concentrations caused consistent significant shifts in bacterial community structure and function. These thresholds of community shifts were also linked to changes in the trophic state of receiving waters in terms of nutrient concentrations. Differences in the community responses along the effluent concentration gradient were primarily driven by two globally relevant bacterial indicator taxa, namely Malikia spp. (Burkholderiales) and hgcI_clade (Frankiales). Species replacement occurred above moderate effluent concentrations with abundances of Malikia spp. increasing, while abundances of hgcI_clade decreased. The responses of Malikia spp. and hgcI_clade matched gene patterns associated with globally important nitrogen cycling pathways, such as denitrification and nitrogen fixation, which linked the core individual taxa to putative function and ecosystem processes, rarely achieved in previous studies. This study has identified potential indicators of change in trophic status and the functional consequences of wastewater pollution. These findings have immediate implications for both the management of environmental stressors and protection of aquatic ecosystems.

Reactive astrogliosis in the dentate gyrus of mice exposed to active volcanic environments

Air pollution has been associated with neuroinflammatory processes and is considered a risk factor for the development of neurodegenerative diseases. Volcanic environments are considered a natural source of air pollution. However, the effects of natural source air pollution on the central nervous system (CNS) have not been reported, despite the fact that up to 10% of the world's population lives near a historically active volcano. In order to assess the response of the CNS to such exposure, our study was conducted in the island of Sao Miguel (Azores, Portugal) in two different areas: Furnas, which is volcanically active one, and compared to Rabo de Peixe, a reference site without manifestations of active volcanism using Mus musculus as a bioindicator species. To evaluate the state of the astroglial population in the dentate gyrus in both samples, the number of astrocytes was determined using immunofluorescence methods (anti-GFAP and anti-GS). In addition, the astrocytic branches in that hippocampal area were examined. Our results showed an increase in GFAP+ astrocytes and a reduction in GS+ astrocytes in Furnas-exposed mice compared to animals from Rabo de Peixe. In addition, astrocytes in the dentate gyrus of chronically exposed animals exhibited longer branches compared to those residing at the reference site. Thus, reactive astrogliosis and astrocyte dysfunction are found in mice living in an active volcanic environment.

Aggregation-Induced Emission Properties in Fully π-Conjugated Polymers, Dendrimers, and Oligomers

Aggregation-Induced Emission (AIE) in organic molecules has recently attracted the attention of the scientific community because of their potential applications in different fields. Compared to small molecules, little attention has been paid to polymers and oligomers that exhibit AIE, despite having excellent properties such as high emission efficiency in aggregate and solid states, signal amplification effect, good processability and the availability of multiple functionalization sites. In addition to these features, if the molecular structure is fully conjugated, intramolecular electronic interactions between the composing chromophores may appear, thus giving rise to a wealth of new photophysical properties. In this review, we focus on selected fully conjugated oligomers, dendrimers and polymers, and briefly summarize their synthetic routes, fluorescence properties and potential applications. An exhaustive comparison between spectroscopic results in solution and aggregates or in solid state has been collected in almost all examples, and an opinion on the future direction of the field is briefly stated.

Design and Synthesis of Annulated Benzothiadiazoles via Dithiolate Formation for Ambipolar Organic Semiconductors

Substituted 2,1,3-benzothiadiazole (BTD) is a widely used electron acceptor unit for functional organic semiconductors. Difluorination or annulation on the 5,6-position of the benzene ring is among the most adapted chemical modifications to tune the electronic properties, though each sees its own limitations in regulating the frontier orbital levels. Herein, a hitherto unreported 5,6-annulated BTD acceptor, denoted as ssBTD, is designed and synthesized by incorporating an electron-withdrawing 2-(1,3-dithiol-2-ylidene)malononitrile moiety via aromatic nucleophilic substitution of the 5,6-difluoroBTD (ffBTD) precursor. Unlike the other reported BTD annulation strategies, this modification leads to the simultaneous decrease in both frontier orbital energies, a welcoming feature for photovoltaic applications. Incorporation of ssBTD into conjugated polymers results in materials boasting broad light absorption, dramatic solvatochromic and thermochromic responses (>100 nm shift and a band gap difference of ∼0.28 eV), and improved crystallinity in the solid state. Such physical properties are in accordance with the combined electron-withdrawing effect and significantly increased polarity associated with the ssBTD unit, as revealed by detailed theoretical studies. Furthermore, the thiolated ssBTD imbues the polymer with ambipolar charge transport property, in contrast to the ffBTD-based polymer, which transports holes only. While the low mobilities (10^-4 to 10^-5 cm² V^-1 s^-1) could be further optimized, detailed studies validate that the thioannulated BTD is a versatile electron-accepting unit for the design of functional stimuli-responsive optoelectronic materials.

Shedding Light on the Origin of Solid-State Luminescence Enhancement in Butterfly Molecules

Different molecular strategies have been carefully evaluated to produce solid-state luminescence enhancement (SLE) in compounds that show dark states in solution. A set of α-phenylstyrylarene derivatives with a butterfly shape have been designed and synthesised, for the first time, with the aim of improving the solid-state fluorescence emission of their parent styrylarene compounds. Although these butterfly molecules are not fluorescent in solution, one of them (1,2,4,5-tetra(α-phenylstyryl)benzene) exhibits a fluorescence quantum yield as high as 68 % in a drop-cast sample and 31 % in its crystalline form. In contrast, 1,3,5-tris(α-phenylstyryl)benzene and 4,6-bis(α-phenylstyryl)pyrimidine do not show SLE. A range of fluorescence spectroscopy experiments and DFT calculations were carried out to unravel the origin of different photophysical behaviour of these compounds in the solid state. The results indicate that a rational strategy to control the SLE effect in luminogens depends on a delicate balance between molecular properties and inter-/intramolecular interactions in the solid state.

Comparative in silico design and validation of GPS™ CoVID-19 dtec-RT-qPCR test

AIMS

Providing a ready-to-use reverse transcriptase qPCR (RT-qPCR) method fully validated to detect the SARS-CoV-2 with a higher exclusivity than this shown by early published RT-qPCR designs.

METHODS AND RESULTS

The specificity of the GPS™ CoVID-19 dtec-RT-qPCR test by analysis of sequence alignments was approached and compared with other RT-qPCR designs. The GPS™ CoVID-19 dtec-RT-qPCR test was validated following criteria of UNE/EN ISO 17025:2005 and ISO/IEC 15189:2012. Diagnostic validation was achieved by two independent reference laboratories, the Instituto de Salud Carlos III, (Madrid, Spain), the Public Health England (Colindale, London, UK), and received the label CE-IVD. The GPS design showed the highest exclusivity and passed all parameters of validation with strict acceptance criteria. Results from reference laboratories 100% correlated with these obtained by using reference methods and showed 100% of diagnostic sensitivity and specificity.

CONCLUSIONS

The CE-IVD GPS™ CoVID-19 dtec-RT-qPCR test, available worldwide with full analytical and diagnostic validation, is the more exclusive for SARS-CoV-2 by far.

SIGNIFICANCE AND IMPACT OF THE STUDY

Considering the CoVID-19 pandemic status, the exclusivity of RT-qPCR tests is crucial to avoid false positives due to related coronaviruses. This work provides of a highly specific and validated RT-qPCR method for detection of SARS-CoV-2, which represents a case of efficient transfer of technology successfully used since the pandemic was declared.

Nature (Hole or Electron) of Charge-Transfer Ability of Substituted Cyclopyrenylene Hoop-Shaped Compounds

We theoretically investigate here by means of DFT methods how the selective substitution in cyclic organic nanorings composed of pyrene units may promote semiconducting properties, analyzing the energy needed for a hole- or electron-transfer accommodation as a function of the substitution pattern and the system size (i.e., number of pyrene units). We choose to study both [3]Cyclo-2,7-pyrenylene ([3]CPY) and [4]Cyclo-2,7-pyrenylene ([4]CPY) compounds, the latter already synthesized, with substituents other than hydrogen acting in ipso and ortho positions, as well as the effect of the per-substitution. As substituents, we selected a set of electroactive halogen atoms (F, Cl, and Br) and groups (CN) to disclose structure-property relationships allowing thus to anticipate the use of these systems as organic molecular semiconductors.

Reversible Interlayer Sliding and Conductivity Changes in Adaptive Tetrathiafulvalene-Based Covalent Organic Frameworks

Ordered interlayer stacking is intrinsic in two-dimensional covalent organic frameworks (2D COFs) and has strong implications on COF's optoelectronic properties. Reversible interlayer sliding, corresponding to shearing of 2D layers along their basal plane, is an appealing dynamic control of both structures and properties, yet it remains unexplored in the 2D COF field. Herein, we demonstrate that the reversible interlayer sliding can be realized in an imine-linked tetrathiafulvalene (TTF)-based COF TTF-DMTA. The solvent treatment induces crystalline phase changes between the proposed staircase-like sql net structure and a slightly slipped eclipsed sql net structure. The solvation-induced crystallinity changes correlate well with reversible spectroscopic and electrical conductivity changes as demonstrated in oriented COF thin films. In contrast, no reversible switching is observed in a related TTF-TA COF, which differs from TTF-DMTA in terms of the absence of methoxy groups on the phenylene linkers. This work represents the first 2D COF example of which eclipsed and staircase-like aggregated states are interchangeably accessed via interlayer sliding, an uncharted structural feature that may enable applications such as chemiresistive sensors.

A highly substituted pyrazinophane generated from a quinoidal system via a cascade reaction

The generation of a highly-substituted [2.2](2,5)pyrazinophane via a cascade reaction is presented. The pyrazinophane product is formed via the dimerization of a member of the para-azaquinodimethane (p-AQM) family of conjugated quinoidal compounds-reactivity that sheds light on the nature of stability in p-AQMs. Additionally, the electronic and structural nature of this highly-strained ring system are characterized.

Understanding the Driving Mechanisms of Enhanced Luminescence Emission of Oligo(styryl)benzenes and Tri(styryl)-s-triazine

This work is focused on unraveling the mechanisms responsible for the aggregation-induced enhanced emission and solid-state luminescence enhancement effects observed in star-shaped molecules based on 1,3,5-tris(styryl)benzene and tri(styryl)-s-triazine cores. To achieve this, the photophysical properties of this set of molecules were analyzed in three states: free molecules, molecular aggregates in solution, and the solid state. Different spectroscopy and microscopy experiments and DFT calculations were conducted to scrutinize the causative mechanisms of the luminescence enhancement phenomenon observed in some experimental conditions. Enhanced luminescence emission was interpreted in the context of short- and long-range excitonic coupling mechanisms and the restriction of intramolecular vibrations. Additionally, we found that the formation of π-stacking aggregates could block E/Z photoisomerization through torsional motions between phenylene rings in the excited state, and hence, enhancing the luminescence of the system.

Analysis of mismatch repair (MMR) proteins expression in a series of malignant pleural mesothelioma (MPM) patients

BACKGROUND

Promising results have been reported with immune checkpoint inhibitors (ICI) in a small proportion of MPM patients. MMR deficiency (dMMR) has been well described in several malignancies and was approved as a biomarker for anti-PD-1 inhibitors. Next generation sequencing (NGS) data demonstrated that 2% of MPM harbor microsatellite instability. The aim of this study is to characterize MMR by immunohistochemistry (IHC) in a series of MPM including a subset of patients treated with immunotherapy.

METHODS

Tumors of 159 MPM p diagnosed between 2002 and 2017 were reviewed. Formalin-fixed, paraffin-embedded tissue was stained for MLH1, MSH2, MSH6 and PMS2 and tumors were classified as dMMR (MMR protein expression negative) and MMR intact (all MMR proteins positively expressed). We retrospectively collected clinical outcomes under standard chemotherapy and experimental immunotherapy in the entire cohort.

RESULTS

MMR protein expression was analyzed in 158 samples with enough tissue and was positive in all of the cases. Twenty two patients received ICI with anti-CTLA4 or anti-PD-1 blockade in clinical trials, 58% had a response or stable disease for more than 6 m, with median progression-free survival (PFS) of 5.7 m (2.1-26.1 m). The median overall survival (mOS) in all population was 15 months (m) (13.5-18.8 m). In a multivariable model factors associated to improved mOS were PS 0, neutrophil-lymphocyte ratio (NLR) < 5 and epithelioid histology (p < 0.001).

CONCLUSIONS

In our series we were unable to identify any MPM patient with dMMR by IHC. Further studies are needed to elucidate potential predictive biomarkers of ICI benefit in MPM.

Synthesis and photophysical studies of an indigo derivative: N-octyl-7,7′-diazaindigo

In this paper, we explore the synthesis, characterization, and photophysical properties of a novel indigo derivative, N-octyl-7,7′-diazaindigo, being the first time that diazaindigos have been studied as photophysically-active chemical entities. Reduction of the neutral “keto-form” to the so-called “leuco-form” changes the global spectroscopic and photophysical behaviors. Both species have been investigated by different photophysical studies, such as analysis of absorption and emission spectra, fluorescence quantum yields (Φ_F) and lifetimes. Finally, to appraise in depth the deactivation of the excited state of the keto form, femtosecond transient absorption (TA) experiments and Density Functional Theory (DFT) and Time Dependent (TD)-DFT calculations were performed. In an organic aprotic solvent (N,N-dimethylformamide), TA experiments showed a fast deactivation channel (τ₁ = 2.9 ps), which was ascribed to solvent reorganization, and a longer decay component (τ₂ = 86 ps) associated with an internal conversion (IC) process to the ground-state, in opposition to the excited state proton transfer (ESPT) mechanism that takes place in the indigo molecules but in protic solvents. A comparative study was also carried out on the parent molecule, 7,7′-diazaindigo, corroborating the previous conclusions obtained for the alkyl derivative. In agreement with experimental observations, DFT and TD-DFT calculations revealed that the deactivation of the S₁ state of the keto form takes place through an internal conversion process.

We report the synthesis, characterization, photophysical properties, and theoretical calculations of a novel indigo derivative, N-octyl-7,7′-diazaindigo.

Immunotherapeutic maintenance treatment with toll-like receptor 9 agonist lefitolimod in patients with extensive-stage small-cell lung cancer: results from the exploratory, controlled, randomized, international phase II IMPULSE study

Background

The immune surveillance reactivator lefitolimod (MGN1703), a DNA-based TLR9 agonist, might foster innate and adaptive immune response and thus improve immune-mediated control of residual cancer disease. The IMPULSE phase II study evaluated the efficacy and safety of lefitolimod as maintenance treatment in extensive-stage small-cell lung cancer (ES-SCLC) after objective response to first-line chemotherapy, an indication with a high unmet medical need and stagnant treatment improvement in the last decades.

Patients and methods

103 patients with ES-SCLC and objective tumor response (as per RECIST 1.1) following four cycles of platinum-based first-line induction therapy were randomized to receive either lefitolimod maintenance therapy or local standard of care at a ratio of 3 : 2 until progression or unacceptable toxicity.

Results

From 103 patients enrolled, 62 were randomized to lefitolimod, 41 to the control arm. Patient demographics and response patterns to first-line therapy were balanced. Lefitolimod exhibited a favorable safety profile and pharmacodynamic assessment confirmed the mode-of-action showing a clear activation of monocytes and production of interferon-gamma-induced protein 10 (IP-10). While in the intent-to-treat (ITT) population no relevant effect of lefitolimod on progression-free and overall survival (OS) could be observed, two predefined patient subgroups indicated promising results, favoring lefitolimod with respect to OS: in patients with a low frequency of activated CD86⁺ B cells (hazard ratio, HR 0.53, 95% CI: 0.26–1.08; n = 38 of 88 analyzed) and in patients with reported chronic obstructive pulmonary disease (COPD) (HR 0.48, 95% CI: 0.20–1.17, n = 25 of 103).

Conclusions

The IMPULSE study showed no relevant effect of lefitolimod on the main efficacy end point OS in the ITT, but (1) the expected pharmacodynamic response to lefitolimod, (2) positive OS efficacy signals in two predefined subgroups and (3) a favorable safety profile. These data support further exploration of lefitolimod in SCLC.