Since 1959 with the proposal of Double Agar Layer (DAL) method for phage detection and quantification, many sophisticated methods have emerged meanwhile. However, many of them are either too ...complex/expensive or insensitive to replace routine utilization of DAL method in clinical, environmental and industrial environments. For that purpose, we have explored an alternative method for the detection and quantification of bacteriophages that fulfills the criteria of being rapid, simple and inexpensive. In this paper we have developed a method based on the analysis of optical density kinetics in bacterial cultures exposed to phage-containing samples. Although the decrease in optical density caused by cell lysis was one of the first observable consequences of the effect of viral infection in bacterial cultures, the potential of the method for the assessment of phage abundance has never been fully exploited. In this work we carry out a detailed study of optical density kinetics in phage-infected bacterial cultures, as a function of both, phage abundance and initial concentration of the host organisms. In total, 90 different combinations of bacteria/phage concentrations have been used. The data obtained provide valuable information about sensitivity ranges, duration of the assay, percentages of inhibition and type of lysing behavior for each phage concentration. The method described can detect, as few as 10 phage particles per assay volume after a phage incubation period of 3.5h. The duration of the assay can be shortened to 45min at the expense of losing sensitivity and increasing the limit of detection to 108 pfu/ml. Despite using non-sophisticated technology, the method described has shown sensitivity and response time comparable to other high-end methods. The simplicity of the technology and of the analytical steps involved, make the system susceptible of miniaturization and automation for high-throughput applications which can be implemented in routine analysis in many environments.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Background
Mepolizumab and omalizumab are treatments for distinct but overlapping severe asthma phenotypes.
Objective
To assess if patients eligible for both biologics but not optimally controlled ...with omalizumab experience improved asthma control when switched directly to mepolizumab.
Methods
OSMO was a multicenter, open‐label, single‐arm, 32‐week trial in patients with ≥2 asthma exacerbations in the year prior to enrollment, despite receiving high‐dose inhaled corticosteroids and other controller(s), plus omalizumab (≥4 months). At baseline, patients with blood eosinophil counts ≥150 cells/µL (or ≥300 cells/µL in the prior year) and an Asthma Control Questionnaire (ACQ)‐5 score ≥1.5 discontinued omalizumab and immediately commenced mepolizumab 100 mg subcutaneously every 4 weeks. Endpoints included change from baseline in ACQ‐5 score (primary), St George's Respiratory Questionnaire (SGRQ) score and the proportions of ACQ‐5 and SGRQ responders, all at Week 32, and the annualized exacerbation rate over the study period.
Results
At Week 32 (intent‐to‐treat population n = 145), the least squares (LS) mean changes (standard error SE) in ACQ‐5 and SGRQ total scores were −1.45 (0.107) and −19.0 (1.64) points; with 77% and 79% of patients achieving the minimum clinically important differences (ACQ‐5: ≥0.5 points; SGRQ: ≥4 points), respectively. The annualized rate of clinically significant exacerbations was 1.18 events/year, a 64% reduction from 3.26 events/year during the previous year. Safety and immunogenicity profiles were consistent with previous trials.
Conclusion
After directly switching from omalizumab to mepolizumab, patients with uncontrolled severe eosinophilic asthma experienced clinically significant improvements in asthma control, health status, and exacerbation rate, with no tolerability issues reported.
Minimal clinically important difference for improvement in asthma control questionnaire‐5 and St. George's Respiratory Questionnaire total scores was achieved by 77% and 79% of patients, respectively. Annualized rate of clinically significant exacerbations was reduced from 3.26 to 1.18 events/year. Safety and immunogenicity profiles of mepolizumab were consistent with previous placebo‐controlled trials in severe eosinophilic asthma.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The surface plasmon resonance (SPR) technique is a well-established method for the measurement of molecules binding to surfaces and the quantification of binding constants between surface-immobilized ...proteins and proteins in solution. In this paper we describe an extension of the methodology to study bacteriophage-bacterium interactions. A two-channel microfluidic SPR sensor device was used to detect the presence of somatic coliphages, a group of bacteriophages that have been proposed as fecal pollution indicators in water, using their host, Escherichia coli WG5, as a target for their selective detection. The bacterium, E. coli WG5, was immobilized on gold sensor chips using avidin-biotin and bacteriophages extracted from wastewater added. The initial binding of the bacteriophage was observed at high concentrations, and a separate, time-delayed cell lysis event also was observed, which was sensitive to bacteriophage at low concentrations. As few as 1 PFU/ml of bacteriophage injected into the chamber could be detected after a phage incubation period of 120 min, which equates to an approximate limit of detection of around 10² PFU/ml. The bacteriophage-bacterium interaction appeared to cause a structural change in the surface-bound bacteria, possibly due to collapse of the cell, which was observed as an increase in mass density on the sensor chip. These results suggest that this methodology could be employed for future biosensor technologies and for quantification of the bacteriophage concentration.
In the development of colorimetric biosensors, the use of electrochromic mediators has been accepted and widely used during decades. The main drawback of these types of enzymatic substrates is the ...difficult recovery of the initial redox state of the molecule, which can be done electrochemically or by antioxidants addition, complicating the initially simple structure of the biosensor. those strategies are rarely followed Actually, being the disposable biosensor configuration the most extended for this detection mechanisms. Alternatively, we propose the first reported use of a diacid dithienylethene 1,2‐bis(5‐carboxy‐2‐methylthien‐3‐yl)cyclopentene (DTE) photoelectrochromic compound as a substrate of the horseradish peroxidase (HRP). The photoisomerization between the open (DTEo) and closed (DTEc) forms of the molecule and the respective shift in the redox potential allowed the light‐induced enzymatic detection of glucose in the glucose oxidase (GOx)–HRP cascade system. This fast and easy control over the enzymatic substrate availability by light pulses permits a gradually consumption and the light‐regeneration of the biosensor for a number of cycles. We consider the presented results transcendent in the development of reusable and light‐controlled photonic biosensing systems.
Switch and detect: A new biosensor based on a diacid dithienylethene (DTE) dye was found, which due to its light‐driven photoisomerization allowed the enzymatic detection of glucose in the glucose oxidase (GOx)–horseradish (HRP) cascade system.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The application of molecular switches for the fabrication of multistimuli-responsive chromic materials and devices still remains a challenge because of the restrictions imposed by the supporting ...solid matrices where these compounds must be incorporated: they often critically affect the chromic response as well as limit the type and nature of external stimuli that can be applied. In this work, we propose the use of ionogels to overcome these constraints, as they provide a soft, fluidic, transparent, thermally stable, and ionic-conductive environment where molecular switches preserve their solution-like properties and can be exposed to a number of different stimuli. By exploiting this strategy, we herein pioneer the preparation of nitrospiropyran-based materials using a single solid platform that exhibit optimal photo-, halo-, thermo-, and electrochromic switching behaviors.
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IJS, KILJ, NUK, PNG, UL, UM
Paralelamente a las representaciones de los medios de comunicación, los memes se han constituido en un instrumento poderoso de los usuarios en internet para transmitir opiniones y expresar emociones ...sobre la guerra. Esto ha dado lugar a un fenómeno comunicativo impensado: hablar sobre este hecho con humor, a pesar de los miles de muertos y millones de desplazados. Dado su carácter persuasivo y difusión exponencial, los memes aportan a la creación de la opinión pública y la realidad social. Por esa razón, este estudio pretende descifrar y describir los significados que predominan en los memes más populares sobre este acontecimiento e identificar su intención emocional o cognitiva, la retórica y el estilo del humor que emplean, su finalidad y, en el caso de los memes considerados perjudiciales o dañinos, sus objetivos y público al que apunta el daño. A partir de un análisis retórico y de contenido aplicado a los 10 memes más populares en Twitter se encontró que estos tienen una alta carga moral: señalan los errores de otros. Las críticas están dirigidas a América Latina, a Putin, a los medios de comunicación occidentales y la Organización del Tratado del Atlántico Norte (OTAN). La emoción y la intención predominantes son el miedo y la crítica social. El carácter intertextual de los memes implica tres grados de dependencia semántica. Estos resultados dan cuenta de que detrás de su humor aparentemente inofensivo se permean ideologías, perspectivas y críticas sociales que encuentran apoyo en la red.
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CEKLJ, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, UL, UM, UPUK
Occupational exposure is an important, global cause of respiratory disease. Unlike many other non-communicable lung diseases, the proximal causes of many occupational lung diseases are well ...understood and they should be amenable to control with use of established and effective approaches. Therefore, the risks arising from exposure to silica and asbestos are well known, as are the means of their prevention. Although the incidence of occupational lung disease has decreased in many countries, in parts of the world undergoing rapid economic transition and population growth-often with large informal and unregulated workforces-occupational exposures continue to impose a heavy burden of disease. The incidence of interstitial and malignant lung diseases remains unacceptably high because control measures are not implemented or exposures arise in novel ways. With the advent of innovative technologies, new threats are continually introduced to the workplace (eg, indium compounds and vicinal diketones). In developed countries, work-related asthma is the commonest occupational lung disease of short latency. Although generic control measures to reduce the risk of developing or exacerbating asthma are well recognised, there is still uncertainty, for example, with regards to the management of workers who develop asthma but remain in the same job. In this Review, we provide recommendations for research, surveillance, and other action for reducing the burden of occupational lung diseases.
The detection of living organisms at very low concentrations is necessary for the early diagnosis of bacterial infections, but it is still challenging as there is a need for signal amplification. ...Cell culture, nucleic acid amplification, or nanostructure-based signal enhancement are the most common amplification methods, relying on long, tedious, complex, or expensive procedures. Here, we present a cyanotype-based photochemical amplification reaction enabling the detection of low bacterial concentrations up to a single-cell level. Photocatalysis is induced with visible light and requires bacterial metabolism of iron-based compounds to produce Prussian Blue. Bacterial activity is thus detected through the formation of an observable blue precipitate within 3 h of the reaction, which corresponds to the concentration of living organisms. The short time-to-result and simplicity of the reaction are expected to strongly impact the clinical diagnosis of infectious diseases.
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IJS, KILJ, NUK, PNG, UL, UM
Current diagnosis of chronic hypersensitivity pneumonitis (cHP) involves considering a combination of clinical, radiological, and pathological information in multidisciplinary team discussions. ...However, this approach is highly variable with poor agreement between centers.
We aimed to identify diagnostic criteria for cHP that reach consensus among international experts.
A 3-round modified Delphi survey was conducted between April and August 2017. Forty-five experts in interstitial lung disease from 14 countries participated in the online survey. Diagnostic items included in round 1 were generated using expert interviews and literature review. During rounds 1 and 2, experts rated the importance of each diagnostic item on a 5-point Likert scale. The a priori threshold of consensus was ≥ 75% of experts rating a diagnostic item as very important or important. In the third round, experts graded the items that met consensus as important and provided their level of diagnostic confidence for a series of clinical scenarios.
Consensus was achieved on 18 of the 40 diagnostic items. Among these, experts gave the highest level of importance to the identification of a causative antigen, time relation between exposure and disease, mosaic attenuation on chest imaging, and poorly formed non-necrotizing granulomas on pathology. In clinical scenarios, the diagnostic confidence of experts in cHP was heightened by the presence of these diagnostic items.
This consensus-based approach for the diagnosis of cHP represents a first step towards the development of international guidelines for the diagnosis of cHP.
Severe asthma affects an estimated 5–10% of the total asthma patient population 1. Various demographic factors, such as sex, age, obesity and age of onset, have been associated with asthma disease ...severity 2, 3, and the efficacy of asthma treatments has previously been found to vary depending on patient demographics 4, 5.
Dupilumab treatment
versus
placebo improved exacerbation rate and lung function outcomes in patients with uncontrolled moderate-to-severe asthma and high type 2 biomarkers at baseline, regardless of baseline characteristics in the phase 3 QUEST study
https://bit.ly/3yR7MlD
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