Prioritizing research challenges and funding for allergy and asthma and the need for translational research—The European Strategic Forum on Allergic Diseases

The European Academy of Allergy and Clinical Immunology (EAACI) organized the first European Strategic Forum on Allergic Diseases and Asthma. The main aim was to bring together all relevant stakeholders and decision‐makers in the field of allergy, asthma and clinical Immunology around an open debate on contemporary challenges and potential solutions for the next decade. The Strategic Forum was an upscaling of the EAACI White Paper aiming to integrate the Academy's output with the perspective offered by EAACI's partners. This collaboration is fundamental for adapting and integrating allergy and asthma care into the context of real‐world problems. The Strategic Forum on Allergic Diseases brought together all partners who have the drive and the influence to make positive change: national and international societies, patients’ organizations, regulatory bodies and industry representatives. An open debate with a special focus on drug development and biomedical engineering, big data and information technology and allergic diseases and asthma in the context of environmental health concluded that connecting science with the transformation of care and a joint agreement between all partners on priorities and needs are essential to ensure a better management of allergic diseases and asthma in the advent of precision medicine together with global access to innovative and affordable diagnostics and therapeutics.     

Enhanced conversion of sterols to steroid synthons by augmenting the peptidoglycan synthesis gene pbpB in Mycobacterium neoaurum

Some species of mycobacteria have been modified to transform sterols to valuable steroid synthons. The unique cell wall of mycobacteria has been recognized as an important organelle to absorb sterols. Some cell wall inhibitors (e.g., vancomycin and glycine) have been validated to enhance sterol conversion by interfering with transpeptidation in peptidoglycan biosynthesis. Therefore, two transpeptidase genes, pbpA and pbpB, were selected to rationally modify the cell wall to simulate the enhancement effect of vancomycin and glycine on sterol conversion in a 22‐hydroxy‐23,24‐bisnorchol‐4‐ene‐3‐one (4‐HBC) producing strain (WIII). Unexpectedly, the pbpA or pbpB gene augmentation was conducive to the utilization of sterols. The pbpB augmentation strain WIII‐pbpB was further investigated for its better performance. Compared to WIII, the morphology of WIII‐pbpB was markedly changed from oval to spindle, indicating alterations of the cell wall. Biochemical analysis indicated that the altered cell wall properties of WIII‐pbpB might contribute to the positive effect on sterol utilization. The productivity of 4‐HBC was enhanced by 28% in the WIII‐pbpB strain compared to that of WIII. These results demonstrated that the modification of peptidoglycan synthesis can improve the conversion of sterols to steroid synthons in mycobacteria.     

A unique telomere DNA expansion phenotype in human retinal rod photoreceptors associated with aging and disease

We have identified a discrete, focal telomere DNA expansion phenotype in the photoreceptor cell layer of normal, non‐neoplastic human retinas. This phenotype is similar to that observed in a subset of human cancers, including a large fraction of tumors of the central nervous system, which maintain their telomeres via the non‐telomerase‐mediated alternative lengthening of telomeres (ALT) mechanism. We observed that these large, ultra‐bright telomere DNA foci are restricted to the rod photoreceptors and are not observed in other cell types. Additionally, focus‐positive rod cells are dispersed homogeneously throughout the posterior retinal photoreceptor cell layer and appear to be human‐specific. We examined 108 normal human retinas obtained at autopsy from a wide range of ages. These large, ultra‐bright telomere DNA foci were not observed in infants before 6 months of age; however, the prevalence of focus‐positive rod cells dramatically increased throughout life. To investigate associations between this phenotype and retinal pathology, we assessed adult glaucoma (N = 29) and diabetic retinopathy (N = 38) cases. Focus‐positive rod cells were prominent in these diseases. When compared to the normal group, after adjusting for age, logistic regression modeling revealed significantly increased odds of falling in the high category of focus‐positive rod cells for glaucoma and diabetic retinopathy. In summary, we have identified a dramatic telomere alteration associated with aging and diseases affecting the retina.     

Mechanism and Factors Influencing Formation and Stability of Chitosan/Lignosulfonate Nanoparticles

A set of new nanoparticles are synthesized in this work at room temperature by combining two oppositely charged non‐toxic biopolymer polyelectrolytes in the form of chitosan and lignosulfonate. The effects of intensity of mixing, solid content, and reactant ratio on nanoparticle size and composition are investigated using turbidity measurements, dynamic light scattering data, zeta potential values, surface tension data, and electron microscopy. The data support nanoparticle structures with a dense hydrophobic core surrounded by a positively charged hydrophilic shell. The chitosan and lignosulfonate domains are held in these nanoparticles primarily by the electrostatic force while hydrogen bonding plays a minor role. The particle size increases with an increase of the total solid content, while the ratio of the two reactants determines the number of particles.     

Preparation of Light‐Responsive Aliphatic Polycarbonate via Versatile Polycondensation for Controlled Degradation

Starting from (2,2,5‐trimethyl‐1,3‐dioxan‐5‐yl)methanamine with light‐responsive 4,5‐dimethoxy‐2‐nitrobenzyl protecting groups, a variety of light‐responsive copolycarbonates (LrPCs) are synthesized by a general two‐step polycondensation using lithium acetylacetonate (LiAcac) as catalyst. UV/Vis, ¹H nuclear magnetic resonance (NMR), and size exclusion chromatography (SEC) confirm the rapid decomposition of these polymers in response to irradiation with UV light. Stable and monodisperse nanoparticles with hydrodynamic diameters of 100 nm, formulated from 25% LrPC and 75% poly(lactic‐co‐glycolic acid) (PLGA), undergo rapid disruption upon triggering with UV light, while standard PLGA nanoparticles remain stable. Moreover, differing from the ring‐opening polymerization (ROP) of trimethylene carbonate‐based monomers, direct polycondensation of 1,3‐propanediol‐based monomers with pendent functional groups and other diols will enable the introduction of various properties into the polycarbonate backbone, and expand the family of biodegradable synthetic polymers for potential biomedical applications.     

Aligned Tubular Conjugated Microporous Polymer Films for the Aggregation‐Induced Emission‐Based Sensing of Explosives

This work shows the sensing performance of conjugated microporous polymer (CMP) tubes. Aligned tubular CMP films (CMP‐AT) are synthesized by a template method. The Sonogashira coupling of tetra(4‐ethynyl)phenylethylene with 1,4‐diiodobenzene in the cylindrical pores of anodic aluminum oxide (AAO) plates and the etching of templates result in the CMP‐AT films. Due to the tetraphenylethylene moieties in the materials, the CMP‐AT films show aggregation‐induced emission (AIE). Based on emission‐quenching behavior, the sensing performance of CMP‐AT films toward model explosives, nitrotoluenes, is studied. The CMP‐AT films having longer CMP tubes with thinner wall thickness show better sensing performance with the Stern–Volmer constant (K_sv) values up to 92 400 M^?1 toward 2,4‐dinitrotoluene. The reduced diffusion pathway of substrates by the thin wall of the CMP tubes is critical for the AIE quenching‐based sensing of nitrotoluenes. These observations indicate that the functionality of CMP materials can be further enhanced by their morphological engineering. Due to the chemical stability of CMP materials, the CMP‐AT‐5 film can be recycled at least five times, maintaining the original sensing performance and tubular morphology.     

Chain Features and Their Influence on the Thermal Stability of Poly(propylene‐co‐1‐nonene) Copolymers

The thermal stability of several isotactic polypropylenes and propylene‐co‐1‐nonene copolymers is assessed under nitrogen by means of thermogravimetric analysis (TGA). The samples involve wide ranges of molecular weight, isotactic average length, and 1‐nonene content, in order to perform a comprehensive analysis of the effect that chain features exert on the apparent activation energy (E_a), in the initial stages of the molten state degradation. The degradation process correlates with chain mobility and, accordingly, with chain features that are linked to. Thus, microstructure and chain size are found to play a key role. In fact, isotactic average length of propylene sequences and molecular weight are driving factors in the E_a required for main chain thermal scission.