RESUMEN
Symmetrical protein cages have evolved to fulfil diverse roles in nature, including compartmentalization and cargo delivery1, and have inspired synthetic biologists to create novel protein assemblies via the precise manipulation of protein-protein interfaces. Despite the impressive array of protein cages produced in the laboratory, the design of inducible assemblies remains challenging2,3. Here we demonstrate an ultra-stable artificial protein cage, the assembly and disassembly of which can be controlled by metal coordination at the protein-protein interfaces. The addition of a gold (I)-triphenylphosphine compound to a cysteine-substituted, 11-mer protein ring triggers supramolecular self-assembly, which generates monodisperse cage structures with masses greater than 2 MDa. The geometry of these structures is based on the Archimedean snub cube and is, to our knowledge, unprecedented. Cryo-electron microscopy confirms that the assemblies are held together by 120 S-Aui-S staples between the protein oligomers, and exist in two chiral forms. The cage shows extreme chemical and thermal stability, yet it readily disassembles upon exposure to reducing agents. As well as gold, mercury(II) is also found to enable formation of the protein cage. This work establishes an approach for linking protein components into robust, higher-order structures, and expands the design space available for supramolecular assemblies to include previously unexplored geometries.
Asunto(s)
Oro/química , Proteínas/química , Microscopía por Crioelectrón , Cisteína/química , Mercurio/química , Modelos Moleculares , Proteínas/ultraestructuraRESUMEN
Introduction: Allergic rhinitis (AR) is the most common allergic disease in the world, and additionally, its prevalence is successively increasing. Children with AR constitute a heterogeneous group of patients differing both in the course of AR and in the frequency of asthma coexistence. It is possible to identify children with AR at risk of a more severe course of the disease by analysing the potential family, environmental and clinical factors related to the development of the disease; the findings will help identify patients with a higher risk of developing asthma in the future, and who will benefit the most from early allergen-specific immunotherapy. Aim: Evaluation of clinical relevance of cluster analysis in phenotyping AR based on an analysis of selected clinical and environmental factors. Material and methods: The study sample was 80 children (7-17 y.o.) with AR, including 28 children with associated asthma. The effects of AR symptoms on the patients daily functioning, skin prick tests (Allergopharma), allergen-specific IgE for airborne allergens (Biocheck GmbH), total cholesterol, cholesterol high-density lipoprotein (HDL), cholesterol low-density lipoprotein (LDL), triglyceride levels in the blood (ARCHITECTcSystem), FeNO and nNO concentrations (HypAir FeNO Medisoft) and results of methacholine challenge test (Lungtest 1000Ispa) were analysed. Results: Four clusters of patients with AR were extracted, differing in the incidence and severity of AR symptoms and the coincidence of asthma. Most of the children from cluster 1 (n = 24; 85.71%) and cluster 2 (n = 15; 78.95%) had persistent AR, while most of the children from cluster 3 (n = 11; 73.33%) and cluster 4 (n = 14; 77.78%) had intermittent AR. The co-occurrence of asthma was significantly higher in cluster 1 than in other clusters (p = 0.0002). Children in clusters 3 and 4 reported a lower impact of AR symptoms on daily functioning (p = 0.0153). Children in cluster 1 had significantly more often an abnormally high total cholesterol level (p = 0.033) and in cluster 4 significantly more often abnormally high triglyceride levels (p = 0.009) were observed. Patients in cluster 2 were significantly less likely to have abnormal high LDL levels (p = 0.015). Conclusions: Children with AR from the Kuyavian-Pomeranian voivodeship differing in the course of AR, the frequency of coexistence of asthma, and occurrence of lipid parameter abnormalities.
RESUMEN
Artificial protein cages have great potential in a number of areas including cargo capture and delivery and as artificial vaccines. Here, we investigate an artificial protein cage whose assembly is triggered by gold nanoparticles. Using biochemical and biophysical methods we were able to determine both the mechanical properties and the gross compositional features of the cage which, combined with mathematical models and biophysical data, allowed the structure of the cage to be predicted. The accuracy of the overall geometrical prediction was confirmed by the cryo-EM structure determined to sub-5 Å resolution. This showed the cage to be nonregular but similar to a dodecahedron, being constructed from 12 11-membered rings. Surprisingly, the structure revealed that the cage also contained a single, small gold nanoparticle at each 3-fold axis meaning that each cage acts as a synthetic framework for regular arrangement of 20 gold nanoparticles in a three-dimensional lattice.
Asunto(s)
Nanopartículas del Metal , Nanopartículas , Oro/química , Nanopartículas del Metal/química , Proteínas/químicaRESUMEN
Introduction: A possible mechanism in the pathogenesis of allergic rhinitis (AR) is hypercholesterolemia, which may shift the balance between Th1- and Th2-dependent immune responses towards the latter. Aim: To assess the prevalence of lipid metabolism abnormalities in children with AR and their influence on the clinical course of AR. Material and methods: The study sample comprised 80 children (7-17 y.o.) with AR, including 28 with associated asthma, and 40 healthy children. Total blood cholesterol, HDL, LDL and triglyceride levels were evaluated (ARCHITECTcSystem). Skin prick tests (Allergopharma) for airborne allergens and a methacholine challenge test (Lungtest 1000, Ispa) were performed. Allergen-specific IgE for airborne allergens (Biocheck GmbH), FeNO and nNO concentrations (HypAir FeNO Medisoft) were measured. Results: Children with AR were significantly more likely to have normal HDL levels than the control group (n = 70; 87.5% vs. n = 27; 67.50%; p = 0.03). No significant differences were observed between these two groups regarding total cholesterol, LDL or triglyceride levels (p > 0.05). Abnormally high total cholesterol levels were associated with a higher risk of sensitisation to D. pteronyssinus (n = 18; 72%, p = 0.023). Children with normal levels of total cholesterol and normal triglyceride values were less likely to be sensitized to dog dander (n = 43; 78.18%, p = 0.049) (n = 42; 72.41%, p = 0.042). No significant correlations were observed between lipid parameters and the clinical course of AR, FeNO concentrations, nNO concentrations and bronchial hyperreactivity in children with AR (p > 0.05). Conclusions: Children with AR are as likely to demonstrate dyslipidaemia as the general population. However, the presence of lipid abnormalities in this group may increase the likelihood of sensitization to perennial allergens.
RESUMEN
Pectobacterium parmentieri is a pectinolytic plant pathogenic bacterium causing high economic losses of cultivated plants. The highly devastating potential of this phytopathogen results from the efficient production of plant cell wall-degrading enzymes, i.e., pectinases, cellulases and proteases, in addition to the impact of accessory virulence factors such as motility, siderophores, biofilm and lipopolysaccharide (LPS). LPS belongs to pathogen-associated molecular patterns (PAMPs) and plays an important role in plant colonization and interaction with the defense systems of the host. Therefore, we decided to investigate the heterogeneity of O-polysaccharides (OPS) of LPS of different strains of P. parmentieri, in search of an association between the selected genomic and phenotypic features of the strains that share an identical structure of the OPS molecule. In the current study, OPS were isolated from the LPS of two P. parmentieri strains obtained either in Finland in the 1980s (SCC3193) or in Poland in 2013 (IFB5432). The purified polysaccharides were analyzed by utilizing 1D and 2D NMR spectroscopy (1H, DQF-COSY, TOCSY, ROESY, HSQC, HSQC-TOCSY and HMBC) in addition to chemical methods. Sugar and methylation analyses of native polysaccharides, absolute configuration assignment of constituent monosaccharides and NMR spectroscopy data revealed that these two P. parmentieri strains isolated in different countries possess the same structure of OPS with a very rare residue of 5,7-diamino-3,5,7,9-tetradeoxy-l-glycero-l-manno-non-2-ulosonic acid (pseudaminic acid) substituted in the position C-8: â3)-ß-d-Galf-(1â3)-α-d-Galp-(1â8)-ß-Pse4Ac5Ac7Ac-(2â6)-α-d-Glcp-(1â6)-ß-d-Glcp-(1â. The previous study indicated that three other P. parmentieri strains, namely IFB5427, IFB5408 and IFB5443, exhibit a different OPS molecule than SCC3193 and IFB5432. The conducted biodiversity-oriented assays revealed that the P. parmentieri IFB5427 and IFB5408 strains possessing the same OPS structure yielded the highest genome-wide similarity, according to average nucleotide identity analyses, in addition to the greatest ability to macerate chicory tissue among the studied P. parmentieri strains. The current research demonstrated a novel OPS structure, characteristic of at least two P. parmentieri strains (SCC3193 and IFB5432), and discussed the observed heterogenicity in the OPS of P. parmentieri in a broad genomic and phenotype-related context.
Asunto(s)
Lipopolisacáridos/genética , Pectobacterium/genética , Plantas/microbiología , Finlandia , Genoma/genética , Genómica/métodos , Fenotipo , Filogenia , Enfermedades de las Plantas/microbiología , Polonia , Factores de Virulencia/genéticaRESUMEN
Drug repurposing in the context of neuroimmunological (NI) investigations is still in its primary stages. Drug repurposing is an important method that bypasses lengthy drug discovery procedures and focuses on discovering new usages for known medications. Neuroimmunological diseases, such as Alzheimer's, Parkinson's, multiple sclerosis, and depression, include various pathologies that result from the interaction between the central nervous system and the immune system. However, the repurposing of NI medications is hindered by the vast amount of information that needs mining. We previously presented Adera1.0, which was capable of text mining PubMed for answering query-based questions. However, Adera1.0 was not able to automatically identify chemical compounds within relevant sentences. To challenge the need for repurposing known medications for neuroimmunological diseases, we built a deep neural network named Adera2.0 to perform drug repurposing. The workflow uses three deep learning networks. The first network is an encoder and its main task is to embed text into matrices. The second network uses a mean squared error (MSE) loss function to predict answers in the form of embedded matrices. The third network, which constitutes the main novelty in our updated workflow, also uses a MSE loss function. Its main usage is to extract compound names from relevant sentences resulting from the previous network. To optimize the network function, we compared eight different designs. We found that a deep neural network consisting of an RNN neural network and a leaky ReLU could achieve 0.0001 loss and 67% sensitivity. Additionally, we validated Adera2.0's ability to predict NI drug usage against the DRUG Repurposing Hub database. These results establish the ability of Adera2.0 to repurpose drug candidates that can shorten the development of the drug cycle. The workflow could be download online.
Asunto(s)
Reposicionamiento de Medicamentos , Redes Neurales de la Computación , Minería de Datos , Descubrimiento de Drogas , Reposicionamiento de Medicamentos/métodos , Flujo de TrabajoRESUMEN
OBJECTIVE: To analyze the characteristics of injuries sustained by young figure skaters who were evaluated at regional pediatric sports medicine clinics. DESIGN: Retrospective chart review (2003-2017). SETTING: Sports medicine clinics at a tertiary-level pediatric medical center. PATIENTS: Two hundred ninety-four figure skaters (271 female and 23 male). Age rage: 9 to 19 years. Mean age: 14.2 ± 2.3 years. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Mechanism of injury (acute vs overuse), injured body areas, diagnoses for most commonly injured body areas, and distribution of bone stress injuries. RESULTS: Eight hundred sixty-four figure skating-related injuries were identified. Approximately 68.9% were overuse and 31.1% were acute. In female figure skaters, the most frequently injured body areas were foot/ankle (29.6%), knee (19.3%), and back (15.8%). In male figure skaters, they were foot/ankle (25.4%), hip (16.4%), and knee (14.9%). Most common diagnoses at these body areas were tendinopathy (foot/ankle), extensor mechanism (knee), and posterior column bone stress injuries (back). All injuries to anterior knee structures, excluding bone contusions, were categorized as extensor mechanism injuries. About 11.8% of all injuries were bone stress reactions/fractures with the majority occurring at the back (42.2%), foot/ankle (32.4%), and lower leg (15.7%). CONCLUSION: Most injuries sustained by figure skaters were overuse and occurred most commonly at the foot/ankle (29.6%), knee (19.3%), and back (15.8%). Approximately 1 in 10 injuries were bone stress reactions/fractures, and nearly 1 in every 3 skaters who presented with back pain was diagnosed with a posterior column bone stress injury. Health care providers who take care of young figure skaters need to maintain a high index of suspicion for overuse injuries, especially bone stress reactions/fractures.
Asunto(s)
Traumatismos en Atletas , Trastornos de Traumas Acumulados , Fracturas por Estrés , Patinación , Adolescente , Traumatismos en Atletas/epidemiología , Niño , Trastornos de Traumas Acumulados/epidemiología , Femenino , Humanos , Masculino , Estudios Retrospectivos , Patinación/lesiones , Medicina Deportiva , Adulto JovenRESUMEN
The effectiveness of opioids in the treatment of neuropathic pain is limited. It was demonstrated that magnesium ions (Mg2+), physiological antagonists of N-methyl-D-aspartate receptor (NMDAR), increase opioid analgesia in chronic pain. Our study aimed to determine the molecular mechanism of this action. Early data indicate the cross-regulation of µ opioid receptor (MOR) and NMDAR in pain control. Morphine acting on MOR stimulates protein kinase C (PKC), while induction of NMDAR recruits protein kinase A (PKA), leading to a disruption of the MOR-NMDAR complex and promoting functional changes in receptors. The mechanical Randall-Selitto test was used to assess the effect of chronic Mg2+ and morphine cotreatment on streptozotocin-induced hyperalgesia in Wistar rats. The level of phosphorylated NMDAR NR1 subunit (pNR1) and phosphorylated MOR (pMOR) in the periaqueductal gray matter was determined with the Western blot method. The activity of PKA and PKC was examined by standard enzyme immunoassays. The experiments showed a reduction in hyperalgesia after coadministration of morphine (5 mg/kg intraperitoneally) and Mg2+ (40 mg/kg intraperitoneally). Mg2+ administered alone significantly decreased the level of pNR1, pMOR, and activity of both tested kinases. The results suggest that blocking NMDAR signaling by Mg2+ restores the MOR-NMDAR complex and thus enables morphine analgesia in neuropathic rats.
Asunto(s)
Analgésicos Opioides/uso terapéutico , Magnesio/uso terapéutico , Morfina/uso terapéutico , Neuralgia/tratamiento farmacológico , Animales , Masculino , Neuralgia/metabolismo , Fosforilación/efectos de los fármacos , Proteína Quinasa C/metabolismo , Ratas Wistar , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Receptores de N-Metil-D-Aspartato/metabolismo , Receptores Opioides mu/metabolismoRESUMEN
Inhibition in task switching is inferred from [Formula: see text] task repetition costs: slower response times and poorer accuracy for ABA task switching sequences compared to CBA sequences, thought to reflect the persisting inhibition of task A across an ABA sequence. Much work has examined the locus of this inhibition effect, with evidence that inhibition targets response selection processes. Consistent with this, fits of the diffusion model to [Formula: see text] task repetition cost data have shown that the cost is reflected by lower estimates of drift rate, suggesting that inhibition impairs information processing efficiency during response selection. However, we have shown that the [Formula: see text] task repetition cost is confounded with episodic retrieval effects which masquerade as inhibitory costs. The purpose of the current study was to conduct a comprehensive analysis of diffusion model fits to new data within a paradigm that controls for episodic interference. Across four experiments (total [Formula: see text]), we find evidence that the reduction of drift rate for [Formula: see text] task repetition costs is only evident under conditions of episodic interference, and the cost is absent when this interference is controlled for. In addition, we also find evidence that episodic retrieval influences task preparation processes and response caution. These findings provide important constraints for theories of task switching that suggest inhibition selectively targets response selection processes.
Asunto(s)
Atención/fisiología , Cognición/fisiología , Función Ejecutiva/fisiología , Inhibición Psicológica , Memoria Episódica , Desempeño Psicomotor/fisiología , Tiempo de Reacción/fisiología , Adulto , Femenino , Humanos , Masculino , Modelos Estadísticos , Análisis y Desempeño de Tareas , Reino Unido , Adulto JovenRESUMEN
Methanotrophic bacteria are able to use methane (CH4) as a sole carbon and energy source. Photochemical oxidation of methane takes place in the stratosphere, whereas in the troposphere, this process is carried out by methanotrophic bacteria. On the one hand, it is known that the efficiency of biological CH4 oxidation is dependent on the mode of land use but, on the other hand, the knowledge of this impact on methanotrophic activity (MTA) is still limited. Thus, the aim of the study was to determine the CH4 oxidation ability of methanotrophic bacteria inhabiting selected arable and no-tillage soils from the Lublin region (Albic Luvisol, Brunic Arenosol, Haplic Chernozem, Calcaric Cambisol) and to identify bacteria involved in this process. MTA was determined based on incubation of soils in air with addition of methane at the concentrations of 0.002, 0.5, 1, 5, and 10%. The experiment was conducted in a temperature range of 10-30 °C. Methanotrophs in soils were identified by next-generation sequencing (NGS). MTA was confirmed in all investigated soils (in the entire range of the tested methane concentrations and temperatures, except for the arable Albic Luvisol). Importantly, the MTA values in the no-tillage soil were nearly two-fold higher than in the cultivated soils. Statistical analysis indicated a significant influence of land use, type of soil, temperature, and especially methane concentration (p < 0.05) on MTA. Metagenomic analysis confirmed the presence of methanotrophs from the genus Methylocystis (Alphaproteobacteria) in the studied soils (except for the arable Albic Luvisol). Our results also proved the ability of methanotrophic bacteria to oxidize methane although they constituted only up to 0.1% of the total bacterial community.
Asunto(s)
Bacterias/aislamiento & purificación , Bacterias/metabolismo , Metano/metabolismo , Microbiología del Suelo , Procesos Autotróficos , Bacterias/clasificación , Bacterias/genética , ADN Bacteriano/genética , Metano/química , Oxidación-Reducción , Filogenia , Polonia , ARN Ribosómico 16S/genética , Suelo/químicaRESUMEN
Nitric oxide is produced by enzymes called nitric oxide synthases. It fulfills many important functions in the human body, but produced in excess amount has a proinflammatory activity. Fractional exhaled nitric oxide measurements are used in the diagnosis and monitoring of eosinophilic inflammation in the lower airways, but should not be used as an independent parameter to make a diagnosis of asthma or for the monitoring of asthma treatment. Evaluation of fractional exhaled nitric oxide concentrations is also used to determine the pathogenesis of symptoms in patients with rhinitis. In addition, they are helpful in detecting and monitoring eosinophilic inflammation in the lower respiratory tract that coexists with inflammation in the upper airways. Fractional exhaled nitric oxide concentrations may be abnormal (lowered or elevated) in other chronic diseases, such as cystic fibrosis, primary ciliary dyskinesia and inflammatory bowel diseases. Many factors, e.g. atopy, genetic polymorphisms of NOS, and the lipid profile affect the fractional exhaled nitric oxide measurement. Nasal nitric oxide measurement is useful in assessing the prevalence and severity of eosinophilic inflammation in the upper respiratory tract.
Asunto(s)
Asma/diagnóstico , Óxido Nítrico/análisis , Rinitis Alérgica/diagnóstico , Adolescente , Pruebas Respiratorias , Niño , Preescolar , Femenino , Humanos , MasculinoRESUMEN
BACKGROUND: Routine imaging follow-up after endovascular treatment of abdominal aortic aneurysms (EVAR) is mainly aimed at detection of endoleaks. The aim of the study was to assess changes in the size of the abdominal aortic aneurysm sack using CT angiography (CTA) after successful treatment using endovascular stent graft implantation. MATERIAL/METHODS: A retrospective analysis of CTA results included 102 patients aged 54-88, who had no postoperative complications. Patients underwent CTA before EVAR and after the treatment (mean time between studies, 7.6 months). The largest cross-sectional area of the aneurysm sac was measured using a curved multiplanar reconstruction. A change of the aneurysm cross-sectional over 10% was considered significant. RESULTS: The average cross-sectional area decreased after EVAR by 3% and this change was not statistically significant. Regression of the cross-sectional area was observed in 18.6% of patients, progression was in 23.5%, and no change was seen in 57.8%. Cross-sectional areas before and after EVAR were significantly correlated (r=0.75, p<0.0001). There was no correlation between the cross-sectional area change after EVAR and patients' age or the time between the treatment and the follow-up CTA. Cross-sectional area before the treatment predicted changes in the aneurysm size after EVAR (p=0.0045). CONCLUSIONS: Remodeling of abdominal aortic aneurysms after EVAR is not uniform. The change of aneurysm size depends on the initial aneurysm size but not on the time from EVAR. The size of the aneurysm after EVAR should not be considered as a measure of the treatment efficacy.
RESUMEN
Microbial degradation is a major determinant of the fate of pollutants in the environment. para-Nitrophenol (PNP) is an EPA-listed priority pollutant with a wide environmental distribution, but little is known about the microorganisms that degrade it in the environment. We studied the diversity of active PNP-degrading bacterial populations in river water using a novel functional marker approach coupled with [(13)C6]PNP stable isotope probing (SIP). Culturing together with culture-independent terminal restriction fragment length polymorphism analysis of 16S rRNA gene amplicons identified Pseudomonas syringae to be the major driver of PNP degradation in river water microcosms. This was confirmed by SIP-pyrosequencing of amplified 16S rRNA. Similarly, functional gene analysis showed that degradation followed the Gram-negative bacterial pathway and involved pnpA from Pseudomonas spp. However, analysis of maleylacetate reductase (encoded by mar), an enzyme common to late stages of both Gram-negative and Gram-positive bacterial PNP degradation pathways, identified a diverse assemblage of bacteria associated with PNP degradation, suggesting that mar has limited use as a specific marker of PNP biodegradation. Both the pnpA and mar genes were detected in a PNP-degrading isolate, P. syringae AKHD2, which was isolated from river water. Our results suggest that PNP-degrading cultures of Pseudomonas spp. are representative of environmental PNP-degrading populations.
Asunto(s)
Nitrofenoles/metabolismo , Pseudomonas/aislamiento & purificación , Pseudomonas/metabolismo , Ríos/microbiología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Biodegradación Ambiental , Isótopos de Carbono/análisis , Isótopos de Carbono/metabolismo , Datos de Secuencia Molecular , Filogenia , Pseudomonas/clasificación , Pseudomonas/genética , ARN Ribosómico 16S/genéticaRESUMEN
Complex mixtures of DNA encoded small molecules may be readily interrogated via high-throughput sequencing. These DNA encoded libraries (DELs) are commonly used to discover molecules that interact with pharmaceutically relevant proteins. The chemical diversity displayed by the library is key to successful discovery of potent, novel, and drug-like chemical matter. The small molecule moieties of DELs are generally synthesized though a multistep process, and each chemical step is accomplished while it is simultaneously attached to an encoding DNA oligomer. Hence, library chemical diversity is often limited to DNA compatible synthetic reactions. Herein, protocols for 24 reactions are provided that have been optimized for high-throughput production of DELs. These protocols detail the multistep synthesis of benzimidazoles, imidazolidinones, quinazolinones, isoindolinones, thiazoles, and imidazopyridines. Additionally, protocols are provided for a diverse range of useful chemical reactions including BOC deprotection (under pH neutral conditions), carbamylation, and Sonogashira coupling. Last, step-by-step protocols for synthesizing functionalized DELs from trichloronitropyrimidine and trichloropyrimidine scaffolds are detailed.
Asunto(s)
ADN/química , Descubrimiento de Drogas/métodos , Bibliotecas de Moléculas Pequeñas/síntesis química , HumanosRESUMEN
Society's reliance upon chemicals over the last few decades has led to their increased production, application and release into the environment. Determination of chemical persistence is crucial for risk assessment and management of chemicals. Current established OECD biodegradation guidelines enable testing of chemicals under laboratory conditions but with an incomplete consideration of factors that can impact on chemical persistence in the environment. The suite of OECD biodegradation tests do not characterise microbial inoculum and often provide little insight into pathways of degradation. The present review considers limitations with the current OECD biodegradation tests and highlights novel scientific approaches to chemical fate studies. We demonstrate how the incorporation of molecular microbial ecology methods (i.e., 'omics') may improve the underlying mechanistic understanding of biodegradation processes, and enable better extrapolation of data from laboratory based test systems to the relevant environment, which would potentially improve chemical risk assessment and decision making. We outline future challenges for relevant stakeholders to modernise OECD biodegradation tests and put the 'bio' back into biodegradation.
Asunto(s)
Biodegradación Ambiental , Bacterias/metabolismo , Genómica , Metabolómica , Organización para la Cooperación y el Desarrollo Económico , Proteómica , Medición de Riesgo , Eliminación de Residuos LíquidosRESUMEN
BACKGROUND: T-cell targeted peptide epitope tolerogens from grass pollen allergens may be useful in treating seasonal allergic rhinitis, but there is urgent need for optimisation of approaches from improved understanding of mechanism. OBJECTIVE: We sought to identify human leukocyte antigen (HLA)-DR1-restricted epitopes from the Timothy grass pollen allergen, Phleum pratense, and characterise T-cell immune regulation following intranasal administration of a single, immunodominant epitope. METHODS: T-cell epitopes within P pratense were identified using HLA-DR1 transgenic mice and tetramer-guided epitope mapping (TGEM) in HLA-DR1-positive individuals with grass allergy. An immunodominant epitope was tested in HLA-DR1 transgenics for impact on responses to whole Phl p5 b or peptide. Microarrays and quantitative PCR were used to characterise T-cell immunity. RESULTS: Peptide 26 (p26) was identified in HLA-DR1 transgenic mice and by TGEM analysis of HLA-DR1-positive individuals with grass allergy. p26 shows promiscuous binding to a wide range of HLA class II alleles, making it of relevance across immunogenetically diverse patients. The epitope is conserved in rye and velvet grass, making it applicable across a spectrum of grass pollen allergy. Intranasal pretreatment of mice with p26 results in significantly reduced T-cell responses. Transcriptomic array analysis in mice showed T-cell regulation in the intranasal treatment group associated with increased expression of members of the Cbl-b and Itch E3 ubiquitin ligase pathway. CONCLUSIONS: We defined an immunodominant P pratense epitope, p26, with broad binding across multiple HLA class II alleles. Intranasal treatment of mice with p26 results in T-cell regulation to whole allergen, involving the Cbl-b and Itch regulatory pathway.
Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/fisiología , Alérgenos/inmunología , Linfocitos T CD4-Positivos/inmunología , Antígeno HLA-DR1/inmunología , Epítopos Inmunodominantes/inmunología , Proteínas de Plantas/inmunología , Polen/inmunología , Proteínas Proto-Oncogénicas c-cbl/fisiología , Rinitis Alérgica Estacional/inmunología , Ubiquitina-Proteína Ligasas/fisiología , Adulto , Animales , Femenino , Humanos , Inmunidad Celular , Masculino , Ratones , Ratones Transgénicos , Análisis por Micromatrices , Persona de Mediana Edad , Phleum/inmunología , Reacción en Cadena en Tiempo Real de la Polimerasa , Reino Unido , Adulto JovenRESUMEN
The aim of the presented work was to functionalize a blend based on polyhydroxyalkanoate (PHA): poly(hydroxybutyrate (PHB) with poly(lactic acid) (PLA) and a mixture of three selected herb extracts, namely, Hypericum L., Urtica L. and Chelidonium L., (E), zinc oxide (ZnO) and a combined system (EZnO), produced via extrusion. Before processing with bioresin, the natural modifiers were characterized using thermal analysis, FTIR and antimicrobial tests. The results revealed interactions between the extracts and the filler, leading to higher thermal stability in EZnO than when using E alone. Moreover, the mixture of extracts exhibited antimicrobial properties toward both Gram-negative (S. aureus) as well as Gram-positive bacteria (E. coli). Modified regranulates were transformed into films by cast extrusion. The influence of the additives on thermal (DSC, TGA and OIT), mechanical, barrier (WVTR and OTR), morphological (FTIR) and optical properties was investigated. The EZnO additive had the highest impact on the mechanical, barrier (OTR and WVTR) and optical properties of the bioresin. The microbial test results revealed that PHA-EZnO exhibited higher activity than PHA-ZnO and PHA-E and also reduced the number of S. aureus, E. coli and C. albicans cells. The findings confirmed the synergistic effect between the additive components. Modified polyester films did not eliminate the phi6 bacteriophage particles completely, but they did decrease their number, confirming moderate antiviral effectiveness.
RESUMEN
A novel photopolymerizable (meth)acrylate oligomer syrup modified with ferulic acid (FA) was verified as an antimicrobial coating binder against a biofilm of Staphylococcus epidermidis. A solution-free UV-LED-initiated photopolymerization process of aliphatic (meth)acrylates and styrene was performed to prepare the oligomer syrup. The influence of ferulic acid on the UV crosslinking process of the varnish coatings (kinetic studies using photo-DSC) as well as their chemical structure (FTIR) and mechanical (adhesion, hardness), optical (gloss, DOI parameter), and antibacterial properties against S. epidermidis were investigated. The photo-DSC results revealed that FA has a positive effect on reducing the early occurrence of slowing processes and has a favorable effect on the monomer conversion increment. It turned out, unexpectedly, that the more FA in the coating, the greater its adhesion to a glass substrate and hardness. The coating containing 0.9 wt. part of FA exhibited excellent antimicrobial properties against S. epidermidis, i.e., the bacterial number after 24 h was only 1.98 log CFU/mL. All the coatings showed relatively high hardness, gloss (>80 G.U.), and DOI parameter values (30-50 a.u.).
RESUMEN
A new type of UV-curable pressure-sensitive adhesive containing Si atoms (Si-PSAs) was prepared by a solution-free UV-initiated telomerization process of n-butyl acrylate, acrylic acid, methyl methacrylate, and 4-acrylooxybenzophenone using triethylsilane (TES) as a telogen and an acylphosphine oxide (APO) as a radical photoinitiator. Selected commercial adhesion promoters were tested as additives in the formulation of adhesive compositions, i.e., (i) an organic copolymer with polar groups (carboxyl and hydroxyl); (ii) a hydroxymetal-organic compound; and (iii) a quaternary ammonium salt and (iv) a chlorinated polyolefin. No fillers, crosslinking agents, or photoinitiators were used in the adhesive compositions. NMR techniques confirmed the incorporation of silicon atoms into the polyacrylate structure. The influence of adhesion promoters on the kinetics of the UV-crosslinking process of Si-PSAs was investigated by a photo-DSC technique. The obtained Si-PSAs were characterized by adhesion (to steel, glass, PMMA, and PE), tack, and cohesion at 20 °C. Finally, the wetting angle of Si-PSAs with water was checked and their thermal stability was proved (TGA). Unexpectedly, the quaternary ammonium salt had the most favorable effect on improving the thermal stability of Si-PSAs (302 °C) and adhesion to glass and PMMA. In contrast, Si-PSAs containing the hydroxymetal-organic compound showed excellent adhesion to steel.