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The processability of organic thermoelectric materials plays a crucial role due to their clear advantages of applicability in large-scale areas compared to traditional inorganic counterparts. A promising way to process thermoelectric materials based on conductive polymers is through in situ polymerization in an insulating polymer matrix. This work shows an interpenetrating polymeric network based on polythiophene, silver nanoparticles (Ag NPs), and poly(methyl methacrylate) (PMMA) produced by the oxidative polymerization of terthiophene by an oxidizing silver salt in a PMMA matrix. Ag NPs are in situ synthesized simultaneously as a byproduct. The reaction occurs very fast in the solid state, and after only 1 min, a homogeneous interpenetrating polymer network (IPN) film is obtained, reaching electrical conductivity values of 120 S cm–1. Ag NPs play a determining role in the conducting properties of the IPN. Moreover, the thermoelectric properties were evaluated as a function of the synthesis parameters, reaching a maximum power factor of 51 μW m–1 K–2. This study shows a promising method to enhance the processability of hybrid thermoelectric materials on the basis of conductive polymers and nanofillers.

Airway obstruction; Cryobiopsy; Paediatric bronchoscopy Obstrucción de las vías respiratorias; Criobiopsia; Broncoscopia pediátrica Obstrucció de les vies respiratòries; Criobiòpsia; Broncoscòpia pediàtrica Background and objective Cryotherapy in interventional bronchoscopy is a new treatment modality, which has recently been made available for the paediatric airway. Lack of experience and safety concerns have led to hesitant adaptation. The aim of this study was to assess indications, success rates and complications of airway cryotherapy in children. Methods Bronchoscopists from medical centre performing cryotherapy in patients between 0 and 18 years were invited to participate in a prospective study based on an online questionnaire. Patient and participant data were collected between June 2020 and June 2021. Results A total of 69 cryotherapy procedures were performed in 57 patients a for three main indications: Biopsy (30), restoration of airway patency (23) and foreign body aspiration (16). The overall success rate was 93%, the remaining 7% were performed for foreign body removal and required a switch of technique. Restoration of airway patency was successfully applied in various pathologies, including mucus plugs, bronchial casts and post traumatic stenosis. The diagnostic yield of transbronchial biopsies was 96%. No severe complications were encountered; one pneumothorax following a cryobiopsy required a chest drain for 48 h. No child was admitted to intensive care or died from a procedural complication. Conclusion In this largest paediatric case collection to date, cryotherapy was safe and carried a high success rate. Cryobiopsy compares favourably to the widely used forceps biopsy and could replace it in the future. Paediatric bronchoscopists are encouraged to add cryotherapy to their armamentarium of airway interventions. Open Access funding enabled and organized by Projekt DEAL.

Stimulating brain tissue regeneration is a major challenge after central nervous system (CNS) injury, such as those observed from trauma or cerebrovascular accidents. Full regeneration is difficult even when a neurogenesis-associated repair response may occur. Currently, there are no effective treatments to stimulate brain tissue regeneration. However, biomaterial scaffolds are showing promising results, where hydrogels are the materials of choice to develop these supportive scaffolds for cell carriers. Their combination with growth factors, such as brain-derived neurotrophic factor (BDNF), basic fibroblast growth factor (bFGF), or vascular endothelial growth factor (VEGF), together with other cell therapy strategies allows the prevention of further neuronal death and can potentially lead to the direct stimulation of neurogenesis and vascularisation at the injured site. Imaging of the injured site is particularly critical to study the reestablishment of neural cell functionality after brain tissue injury. This review outlines the latest key advances associated with different strategies aiming to promote the neuroregeneration, imaging, and functional recovery of brain tissue. Graphical abstract

Lignin in advanced energy applications: source, extraction methodolgy, structure/property relationships.

The development of wearable technology has promoted the research of new power supply sources to feed wearable devices without the need of batteries. Wearable thermoelectric generators (wTEGs) can generate energy using the thermal gradient between the human body and the ambient temperature. The most comfortable way to adapt wTEGs to the human body is by using textiles, which are flexible and breathable. In this work, we have developed a method to coat textiles with conductive polymers by electrodeposition on fabrics previously coated with multi-walled carbon nanotubes (MWCNT). The results show that the fabrics coated with polyaniline: sulfuric acid (PANI:H2SO4) present a very low thermal stability, and the variation of the electrical conductivity under wearable stress is not suitable for their use in smart textiles. However, the fabrics coated with poly (3,4-ethylenedioxythiophene: perchlorate) (PEDOT:ClO4) and polypyrrole: perchlorate (PPy:ClO4) show a good thermal stability, positive evolution of the electrical conductivity as a function of the twist angle, bending cycles, and bending radius, demostrating their potential use in practical wearable applications to coat fabrics by electrochemical deposition.

Electrically conductive bio-scaffolds are being explored in the field of tissue engineering (TE) as a solution to address the clinical need of electroactive tissues, finding applications in nervous, cardiac, and spinal cord injury repair. In this work, we synthesise polypyrrole nanoparticles (PPy NP) via the mini-emulsion method with further combination with a gelatin/hyaluronic acid (HA) hydrogel to create electro-conductive Gel:HA:PPy-NP TE scaffolds. The electro-conductive Gel:HA:PPy-NP scaffolds possess excellent mechanical properties at 1.08 ± 0.26 MPa, closely matching to reported spinal cord mechanical performance. Scaffolds were designed with controlled porosity of 526.2 ± 74.6-403.9 ± 57.4 µm, and conductivities of 4.3×10− 6±1.1×10− 6 S.cm− 1 were reached. Rheological studies show that prior to lyophilisation, the Gel:HA:PPy-NP hydrogels display a shear-thinning behaviour. These gels were subsequently 3D printed into predefined 2 layer lattice geometries and displayed excellent post-printing shape fidelity. In-vitro studies show that the Gel:HA:PPy-NP scaffolds are cytocompatible with mesenchymal stem cells and neuronal stem cells and display encouraging cell attachment and proliferation profiles. Based on these results, the incorporation of PPy NPs into Gel:HA biomaterial scaffolds enhances the conductive capabilities of the material, while showcasing biocompatible behaviour with cell cultures. Hence, Gel:HA:PPy-NPs scaffolds are a promising TE option for the stimulating of nervous tissue injury regeneration.

Curcumin is a known naturally occurring anti-inflammatory agent derived from turmeric, and it is commonly used as a herbal food supplement. Here, in order to overcome the inherent hydrophobicity of curcumin (Cur), polylactic acid (PLA) nanoparticles (NPs) were synthesised using a solvent evaporation, and an oil-in-water emulsion method used to encapsulate curcumin. Polymeric NPs also offer the ability to control rate of drug release. The newly synthesised NPs were analysed using a scanning electron microscope (SEM), where results show the NPs range from 50 to 250 nm. NPs containing graded amounts of curcumin (0 %, 0.5 %, and 2 %) were added to cultures of NIH3T3 fibroblast cells for cytotoxicity evaluation using the Alamar Blue assay. Then, the curcumin NPs were incorporated into an alginate/gelatin solution, prior to crosslinking using a calcium chloride solution (200 nM). These hydrogels were then characterised with respect to their chemical, mechanical and rheological properties. Following hydrogel optimization, hydrogels loaded with NP containing 2 % curcumin were selected as a candidate as a bioink for three-dimensional (3D) printing. The biological assessment for these bioinks/hydrogels were conducted using THP-1 cells, a human monocytic cell line. Cell viability and immunomodulation were evaluated using lactate dehydrogenase (LHD) and a tumour necrosis factor alpha (TNF-α) enzyme-linked immunosorbent (ELISA) assay, respectively. Results show that the hydrogels were cytocompatible and supressed the production of TNF-α. These bioactive hydrogels are printable, supress immune cell activation and inflammation showing immense potential for the fabrication of tissue engineering constructs.

A third-generation glucose biosensor has been developed utilising glucose oxidase (GOx) immobilised on mesoporous carbon nanostructures. These nanostructures were produced from a 50% alcell lignin and 50% polylactic acid (PLA) precursor blend. Methylene diphenyl diisocyanate (MDI) has been incorporated to offset fusion during the thermal stabilisation phase. The PLA is sacrificial at higher carbonisation temperatures and this allows the controlled formation of a high 50% relative volume of mesopores (2–4 nm) within larger pores. The result is a hierarchical structure, ideal for GOx immobilisation, with an increased external area that allows for a high surface coverage of 3.0 × 10−10 mol cm−2 and fast direct electron transfer (DET) of 1.3 s−1 between the mesoporous carbon and the active redox groups of GOx. The immobilised enzyme exhibits strong, selective activity on glucose, with or without oxygen, attributed to its high affinity to the electrode, with a Michaelis–Menten constant Km of 0.600 mM. At optimum conditions, the biosensor exhibits a linear response between 0.15 and 2.7 mM, with a high sensitivity of 50 μA mM−1 cm−2 and a limit of detection (LoD) of 89 μmol L−1 for a signal to noise ratio of 3.

Cellulose, an abundant natural polymer, has promising potential to be used for energy storage systems because of its excellent mechanical, structural, and physical characteristics. This review discusses the structural features of cellulose and describes its potential application as an electrode, separator, and binder, in various types of high-performing batteries. Various surface and structural characteristics of cellulose (e.g., fiber size, surface functional groups, the hierarchy of pores, and porosity levels) that contribute to its electrochemical performance are discussed. Cellulose structure/property/processing/function relationships are further focused and elucidated in terms of the latest developments in the emerging field of sustainable materials in Li-Ion, Na-Ion, and Li–S batteries.

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Abstract In the design of injectable antimicrobial dextran-alginate hydrogels, the impact of dextran oxidation and its subsequent changes in molecular weight and the incorporation of glycol chitosan on (i) gel mechanical strength and (ii) the inhibitory profile of an encapsulated bacteriocin, nisin A, are explored. As the degree of oxidation increases, the weight average molecular mass of the dextran decreases, resulting in a reduction in elastic modulus of the gels made. Upon encapsulation of the bacteriocin nisin into the gels, varying the dextran mass/oxidation level allowed the antimicrobial activity against S. aureus to be controlled. Gels made with a higher molecular weight (less oxidised) dextran show a higher initial degree of inhibition while those made with a lower molecular weight (more oxidised) dextran exhibit a more sustained inhibition. Incorporating glycol chitosan into gels composed of dextran with higher masses significantly increased their storage modulus and the gels’ initial degree of inhibition. Graphical abstract

Sustainable materials are attracting a lot of attention since they will be critical in the creation of the next generation of products and devices. In this study, hydrogels were effectively synthesized utilizing lignin, a non-valorised biopolymer from the paper industry. This study proposes a method based on utilizing lignin to create highly swollen hydrogels using poly(ethylene) glycol diglycidyl ether (PEGDGE) as a crosslinking agent. The influence of different crosslinker ratios on the structural and chemical properties of the resultant hydrogels was investigated. Pore size was observed to be lowered when the amount of crosslinker was increased. The inclusion of additional hydrophilic groups in the hydrogel network decreased the swelling capacity of the hydrogels as the crosslinking density increases. These precursor materials were carbonised and electrochemically tested for application as electrodes for supercapacitors with capacitance characterized as a function of crosslinker ratio.

Segmented thermoplastic polyurethanes (PU) were synthetized using a polycarbonatediol macrodiol as a flexible or soft segment with a molar mass of 2000 g/mol, and different diisocyanate molecules and 1,4-butanediol as a rigid or hard segment. The diisocyanate molecules employed are 3,3′-Dimethyl-4,4′-biphenyl diisocyanate (TODI), 4,4′-diphenylmethane diisocyanate (MDI), 4,4′-Methylenebis(phenyl isocyanate) 1-isocyanato-4-[(4-phenylisocyanate)methyl]benzene and 1-isocyanate-4-[(2-phenylisocyanate) methyl]benzene (ratio 1:1) (MDIi), isophorone diisocyanate (IPDI), and hexamethylene diisocyanate (HDI). The polyurethanes obtained reveal a wide variation of microphase separation degree that is correlated with mechanical properties. Different techniques, such as DSC, DMA, and FTIR, have been used to determine flexible–rigid segment phase behavior. Mechanical properties, such as tensile properties, Shore D hardness, and “compression set”, have been determined. This work reveals that the structure of the hard segment is crucial to determine the degree of phase miscibility which affects the resulting mechanical properties, such as tensile properties, hardness, and “compression set”.

COVID-19; Lung ultrasound (LUS); Pulmonary sequelae COVID-19; Ecografía pulmonar (LUS); Secuelas pulmonares COVID-19; Ecografia pulmonar (LUS); Seqüeles pulmonars Background: Interstitial lung sequelae are increasingly being reported in survivors of COVID-19 pneumonia. An early detection of these lesions may help prevent the development of irreversible lung fibrosis. Lung ultrasound (LUS) has shown high diagnostic accuracy in interstitial lung disease (ILD) and could likely be used as a first-line test for post-COVID-19 lung sequelae. Methods: Single-center observational prospective study. Follow-up assessments of consecutive patients hospitalized for COVID-19 pneumonia were conducted 2–5 months after the hospitalization. All patients underwent pulmonary function tests (PFTs), high-resolution computed tomography (HRCT), and LUS. Radiological alterations in HRCT were quantified using the Warrick score. The LUS score was obtained by evaluating the presence of pathological B-lines in 12 thoracic areas (range, 0–12). The correlation between the LUS and Warrick scores was analyzed. Results: Three hundred and fifty-two patients who recovered from COVID-19 pneumonia were recruited between July and September 2020. At follow-up, dyspnea was the most frequent symptom (69.3%). FVC and DLCO alterations were present in 79 (22.4%) and 234 (66.5%) patients, respectively. HRCT showed relevant interstitial lung sequelae (RILS) in 154 (43.8%) patients (Warrick score ≥ 7). The LUS score was strongly correlated with the HRCT Warrick score (r = 0.77) and showed a moderate inverse correlation with DLCO (r = −0.55). The ROC curve analysis revealed that a LUS score ≥ 3 indicated an excellent ability to discriminate patients with RILS (sensitivity, 94.2%; specificity, 81.8%; negative predictive value, 94.7%). Conclusions: LUS could be implemented as a first-line procedure in the evaluation of Post-COVID-19 interstitial lung sequelae. A normal LUS examination rules out the presence of these sequelae in COVID-19 survivors, avoiding the need for additional diagnostic tests such as HRCT.

BackgroundTransbronchial lung cryobiopsy is an emerging technique for diagnosing pulmonary rejection. However, no prospective studies of this procedure for critically ill lung transplant recipients who require mechanical ventilation in the intensive care unit (ICU) have been performed.MethodsFrom March 2017 to January 2020, we performed a prospective, randomised, comparative study to assess the diagnostic yield, histological quality and safety of transbronchial lung biopsy using biopsy forceps, a 1.9-mm cryoprobe or a 2.4-mm cryoprobe.Results89 out of 129 consecutive transbronchial biopsy procedures (forceps group, 28 procedures; 1.9-mm cryoprobe group, 31 procedures; 2.4-mm cryoprobe group, 30 procedures) were randomised. Compared with lung samples from the forceps and 1.9-mm cryoprobe groups, lung samples from the 2.4-mm cryoprobe group allowed the most definitive diagnoses (pConclusionsTransbronchial lung biopsy using a 2.4-mm cryoprobe allows the safe collection of lung tissue samples from critically ill lung transplant recipients who require mechanical ventilation in the ICU and has good diagnostic performance.

Background Previous studies suggest that transbronchial lung biopsy using a cryoprobe is superior to transbronchial lung biopsy using forceps for evaluating lung grafts, although the technique can be associated an increase in complications. Because cryoprobe experience is limited, assessment of a greater number of cases is warranted. This prospective study evaluates the diagnostic yield, complications, and risk factors associated with the cryoprobe technique. Methods From April 2013 to April 2016, 321 consecutive cryoprobe transbronchial biopsies were indicated in single or bilateral lung transplant patients with acute or chronic clinical lung injury or in asymptomatic patients before hospital discharge after lung transplantation. Results With a mean of 4.32 lung parenchyma specimens per procedure, adequate alveolar lung parenchyma was obtained in 96.6% (84.27 ± 44.14 mm2) of cases. Obtaining at least 4 samples increased the histological diagnostic certainty (P Conclusions Obtaining 4 or more cryobiopsy samples is valuable and safe for lung allograft monitoring. Being a recipient of a unilateral lung transplant or having arterial hypertension during bronchoscopy seem to be risk factors associated with increased bleeding.

Introduction: Comorbidities in patients with bronchiectasis are common and have a significant impact on clinical outcomes, contributing to lower quality of life, lung function, and exacerbation frequency. At least 13 comorbidities have been associated with a higher risk of mortality in bronchiectasis patients. Nonetheless, the kind of relationship between bronchiectasis and comorbidities is heterogeneous and poorly understood.Areas covered: different biological mechanisms leading to bronchiectasis could have a role in the development of the associated comorbidities. Some comorbidities could have a causal relationship with bronchiectasis, possibly through a variable degree of systemic inflammation, such as in rheumatic disorders and bowel inflammatory diseases. Other comorbidities, such as COPD or asthma, could be associated through airway inflammation and there is an uncertain cause-effect relationship. Finally, shared risk factors could link different comorbidities to bronchiectasis such as in the case of cardiovascular diseases, where the known link between chronic systemic inflammation and pulmonary infection could play a significant role.Expert opinion: Although different tools have been developed to assess the role of comorbidities in bronchiectasis , we believe that the implementation of current strategies to manage them is absolutely necessary and could significantly improve long-term prognosis in patients with bronchiectasis.

Background: Non-small cell lung cancer (NSCLC) is usually diagnosed at stages IIIB-IV, with a median overall survival that does not exceed two years. In contrast, patients diagnosed at early and locally advanced stages (I-IIIA) can undergo surgery and have a significantly better prognosis. Imaging technologies often detect lung nodules of unknown significance that pose a diagnostic challenge. In a proof-of-concept study, based on a 76-patient cohort, we developed a preliminary mRNA expression signature in plasma that discriminated healthy individuals from early-stage NSCLC patients with AUC=0.98. Here, we aimed to expand the training cohort, to refine the diagnostic signature and to prospectively validate the final signature in the clinical setting. Methods: Two hundred and thirty individuals with pulmonary nodules suspicious of lung cancer have been enrolled in the training cohort. All of them underwent bronchoscopy, fine needle aspiration, percutaneous or surgical biopsy to confirm the diagnosis. Circulating-free RNA (cfRNA) has been isolated from plasma using an automatic extraction method (Qiasymphony, Qiagen). Purified cfRNA has been quantified using Qubit®, retrotranscribed and pre-amplified with 14 cycles using the Low RNA Input Amplification kit (NanoString Technologies). Gene expression analysis has been performed on the nCounter platform using the PanCancer IO360࣪ panel (NanoString Technologies), which can detect 770 transcripts related to tumor biology, micro-environment and the immune system. Results: One hundred twenty-six patients have been analyzed so far; plasma samples have been successfully analyzed by nCounter in all cases. Ongoing analysis reveal differential patterns of gene expression in early-stage NSCLC patients versus non-cancer individuals. Using a bioinformatics recursive feature elimination algorithm, we have selected a diagnostic signature with an area under the ROC curve of 0.89. The signature scores derived from the algorithm are significantly different between the non-cancer and NSCLC cases. Final results of the training and validation cohort will be presented at the meeting Conclusions: Plasma RNA expression signatures can be a useful tool to guide clinical decision in patients with pulmonary nodules suspicious of malignancy, orienting towards surgery or observation. Citation Format: Ana María Giménez Capitán, Pablo Rubisntein, Andrés Aguilar-Hernández, María González-cao, Irene Moya, Santiago Viteri, Carlos Cabrera, Santiago Ramón y Cajal, Karina Loor, Mario Culebras, Irene Sansano, Federico Rubisntein, Joselyn Valarezo, Clara Mayo-de las-Casas, Carlos Pedraz, Joseph Beechem, Sarah Warren, Rafael Rosell, Miguel Ángel Molina-Vila. Prospective validation of a mRNA signature in plasma for the diagnosis of early stage lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1424.

Biofilm-related infections and contamination of biomaterials are major problems in the clinic. These contaminations are frequently caused by Staphylococcus aureus and are a pressing issue for implantable devices, catheters, contact lenses, prostheses, and wound dressings. Strategies to decrease contamination and biofilm related infections are vital for the success of implantable biomaterials. In this context, hyaluronic acid (HA), a naturally derived carbohydrate polymer, known to be biocompatible, degradable, and immunomodulatory, has shown some antimicrobial activity effects. Due to its poor structural stability, crosslinking strategies, and the incorporation of reinforcing fibres in HA gels is required to produce tailored gels for varying applications. Whilst carbon-based reinforcing materials, such as carbon nanofibers (CNF), present some intrinsic antimicrobial activity related to their high surface area, herein, a crosslinking strategy to enhance the mechanical properties and regulate the rate of degradation of HA is presented. We utilise bis-(β-isocyanatoethyl) disulphide (BIED) as the crosslinker with the gel reinforced using 0.25 wt% CNF. The effects of CNF and BIED on the structural, mechanical, thermal, and swelling behaviour are examined. These new HA derivatives exhibit excellent mechanical properties and are capable of withstanding physiological stresses in vivo. Antimicrobial activity of the HA derivatives were tested against Staphylococcus aureus and the results reveal antibacterial effect. These carbohydrate based materials have potential application on surfaces within clinical settings where staphylococcal contamination is currently an issue.

[EN] Energy harvesting through residual heat is considered one of the most promising ways to power wearable devices. In this work, thermoelectric textiles were prepared by coating the fabrics, first with multiple-wall carbon nanotubes (MWCNTs) by using the layer-by-layer technique and second with poly(3,4-ethylenedioxythiophene) (PEDOT) deposited by electrochemical polymerization. Sodium deoxycholate and poly(diallyldimethylammonium chloride) were used as stabilizers to prepare the aqueous dispersions of MWCNTs. The electrochemical deposition of PEDOT on the MWCNT-coated fabric was carried out in a three-electrode electrochemical cell. The polymerization of PEDOT on the fabric increased the electrical conductivity by ten orders of magnitude (through the plane), establishing an excellent path for electric transport across the fabrics. In addition, the fibers showed a Seebeck coefficient of 14.3 ¿V K¿1, which is characteristic of highly doped PEDOT. As a proof of concept, several thermoelectric modules were made with different elements based on the coated acrylic and cotton fabrics. The best generator made of 30 thermoelectric elements using acrylic fabrics exhibited an output power of 0.9 ¿W with a temperature difference of 31 K., This research was supported by the General Direction of Scientific and Technical Research of the Spanish Government through a grant of the Program Consolider Ingenio (grant no. CSD2010-0044) and grant MAT2015-63955-R. J.F.S.-C. and I.B.-A. acknowledge the financial support by the Spanish Ministry of Education, Culture and Sport through the FPU Training Program. Finally, R.M.-E. thanks the financial support of the Spanish Ministry of Science and Innovation through a Ramon y Cajal grant (grant no. RYC-2013-13451).