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Author(s):  
João Martins ◽  
Adilson Marques ◽  
Élvio Rúbio Gouveia ◽  
Francisco Carvalho ◽  
Hugo Sarmento ◽  
...  

The present study sought to examine the associations between participation in physical education (PE) classes and a range of health-related behaviours among adolescents. Secondary analysis of self-reported data from the Global Student Health Survey, collected between 2010 and 2017 from 222,121 adolescents (N = 117,914 girls; 49.0%; aged 13–17 years) from 67 countries and five world regions, was carried out. Participation in PE classes (0, 1–2, ≥3 days/week) was the independent variable. Physical activity (PA); sedentary behaviour (SB); active travel to school; fruit, vegetables, and alcohol consumption; and smoking; as well as adopting ≥5 of these healthy behaviours; were the dependent variables. Complex samples logistic regressions were performed to explore the associations between participation in PE classes and health-related behaviours. The results revealed that 18.2% of adolescents did not take part in PE classes. A total of 56.7% and 25.1% of adolescents reported participating in PE classes on 1–2 and ≥3 days/week, respectively. Only 26.8% of adolescents adopted ≥5 healthy behaviours. Participation in PE classes was positively associated with PA, active travel, fruit consumption, and vegetable consumption (only for ≥3 days/week), but was negatively associated with meeting SB recommendations, and with not smoking (only for girls and ≥3 days/week). Overall, PE participation was positively associated with adopting ≥5 healthy behaviours, with favourable results found for those who attended more PE classes. The findings revealed a positive association between participation in PE classes and a range of health-related behaviours among adolescents. This suggests that, worldwide, quality PE should be delivered at least 3 days per week up to daily to promote healthy lifestyles among adolescents.


Chemosensors ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 23
Author(s):  
Yupu Zhang ◽  
Xinfeng Du ◽  
Xiaojiang Xie

Fluorescent nanoprobes containing ionophores and solvatochromic dyes (SDs) were previously reported as an alternative to chromoionophore-based nano-optodes. However, the small-molecular SDs are prone to leakage and sequestration in complex samples. Here, we chemically attached the SDs to the surface of organosilica nanospheres through copper-catalyzed Click chemistry to prevent dye leakage. The nano-optodes remained well responsive to K+ even after exposure to a large amount of cation-exchange resin, which acted as a sink of the SDs. The potassium nanoprobes exhibited a dynamic range between 1 μM to 10 mM and a good selectivity thanks to valinomycin. Preliminary sensing device based on a nylon filter paper and agarose hydrogel was demonstrated. The results indicate that the covalent anchoring of SDs on nanospheres is promising for developing ionophore-based nanoprobes.


2022 ◽  
Vol 20 (1) ◽  
Author(s):  
Jiaqi Hu ◽  
Lu Ding ◽  
Jing Chen ◽  
Jinhua Fu ◽  
Kang Zhu ◽  
...  

AbstractHerein, we reported a new dynamic light scattering (DLS) immunosensing technology for the rapid and sensitive detection of glycoprotein N-terminal pro-brain natriuretic peptide (NT-proBNP). In this design, the boronate affinity recognition based on the interaction of boronic acid ligands and cis-diols was introduced to amplify the nanoparticle aggregation to enable highly sensitive DLS transduction, thereby lowering the limit of detection (LOD) of the methodology. After covalently coupling with antibodies, magnetic nanoparticles (MNPs) were employed as the nanoprobes to selectively capture trace amount of NT-proBNP from complex samples and facilitate DLS signal transduction. Meanwhile, silica nanoparticles modified with phenylboronic acid (SiO2@PBA) were designed as the crosslinking agent to bridge the aggregation of MNPs in the presence of target NT-proBNP. Owing to the multivalent and fast affinity recognition between NT-proBNP containing cis-diols and SiO2@PBA, the developed DLS immunosensor exhibited charming advantages over traditional immunoassays, including ultrahigh sensitivity with an LOD of 7.4 fg mL−1, fast response time (< 20 min), and small sample consumption (1 μL). The DLS immunosensor was further characterized with good selectivity, accuracy, precision, reproducibility, and practicability. Collectively, this work demonstrated the promising application of the designed boronate affinity amplified-DLS immunosensor for field or point-of-care testing of cis-diol-containing molecules. Graphical Abstract


2021 ◽  
Vol 23 (1) ◽  
pp. 381
Author(s):  
Andrea C. Büchler ◽  
Vladimir Lazarevic ◽  
Nadia Gaïa ◽  
Myriam Girard ◽  
Friedrich Eckstein ◽  
...  

We present the case of a 72-year-old female patient with acute contained rupture of a biological composite graft, 21 months after replacement of the aortic valve and the ascending aorta due to an aortic dissection. Auramine-rhodamine staining of intraoperative biopsies showed acid-fast bacilli, but classical culture and molecular methods failed to identify any organism. Metagenomic analysis indicated infection with Mycobacterium chelonae, which was confirmed by target-specific qPCR. The complexity of the sample required a customized bioinformatics pipeline, including cleaning steps to remove sequences of human, bovine ad pig origin. Our study underlines the importance of multiple testing to increase the likelihood of pathogen identification in highly complex samples.


2021 ◽  
Vol 3 ◽  
Author(s):  
Wanqin Dai ◽  
Junzhe Zhang ◽  
Yun Wang ◽  
Chunlei Jiao ◽  
Zhuda Song ◽  
...  

Quantifying the distribution of nanomaterials in complex samples is of great significance to the toxicological research of nanomaterials as well as their clinical applications. Radiotracer technology is a powerful tool for biological and environmental tracing of nanomaterials because it has the advantages of high sensitivity and high reliability, and can be matched with some spatially resolved technologies for non-invasive, real-time detection. However, the radiolabeling operation of nanomaterials is relatively complicated, and fundamental studies on how to optimize the experimental procedures for the best radiolabeling of nanomaterials are still needed. This minireview looks back into the methods of radiolabeling of nanomaterials in previous work, and highlights the superiority of the “last-step” labeling strategy. At the same time, the problems existing in the stability test of radiolabeling and the suggestions for further improvement are also addressed.


Chemosensors ◽  
2021 ◽  
Vol 9 (12) ◽  
pp. 356
Author(s):  
Lorena Di Zazzo ◽  
Gabriele Magna ◽  
Martina Lucentini ◽  
Manuela Stefanelli ◽  
Roberto Paolesse ◽  
...  

The correlation between breath volatilome and health is prompting a growing interest in the development of sensors optimized for breath analysis. On the other hand, the outbreak of COVID-19 evidenced that breath is a vehicle of infection; thus, the introduction of low-cost and disposable devices is becoming urgent for a clinical implementation of breath analysis. In this paper, a proof of concept about the functionalization of face masks is provided. Porphyrin-based sensors are among the most performant devices for breath analysis, but since porphyrins are scarcely conductive, they make use of costly and bulky mass or optical transducers. To overcome this drawback, we introduce here a hybrid material made of conducting polymer and porphyrins. The resulting material can be easily deposited on the internal surface of standard FFP face masks producing resistive sensors that retain the chemical sensitivity of porphyrins implementing their combinatorial selectivity for the identification of volatile compounds and the classification of complex samples. The sensitivity of sensors has been tested with respect to a set of seven volatile compounds representative of diverse chemical families. Sensors react to all compounds but with a different sensitivity pattern. Functionalized face masks have been tested in a proof-of-concept test aimed at identifying changes of breath due to the ingestion of beverages (coffee and wine) and solid food (banana- and mint-flavored candies). Results indicate that sensors can detect volatile compounds against the background of normal breath VOCs, suggesting the possibility to embed sensors in face masks for extensive breath analysis


2021 ◽  
Author(s):  
Danka Dragojlović

The aim of this research was to develop reliable, easy-to-perform and cheap method for measuring protein oxidation in complex samples such as aquaculture feed within various protein sources. For that purpose modified 2,4-dinitrophenylhydrazyne (DNPH)-based method for quantification of protein carbonyls was employed, while the method modification was consisted of using different solutions for the extraction, time of protein extraction and concentration of trichloracetic acid (TCA) for protein precipitation. It was found that extraction during night, higher TCA concentration  and the use of  0.5 M KCl extraction solution resulted in the highest protein amount measured by Lowry method and 280 nm protein estimation. On the other hand, the lowest protein yield was obtained by using distillated water for the extraction. Furthermore, the lowest amount of protein carbonyls was in the case when extraction was performed with distilled water (DW), while the highest content of protein carbonyls were reached with 0.15 M KCl and 0.5 M KCl extraction solutions. It was observed that the amount of carbonyls compounds were increasing during storage under accelerated conditions, and in comparison to the original (unmodified) method, the modified method for measuring protein oxidation resulted in the higher amount of carbonyls during the all points of storage.


Molecules ◽  
2021 ◽  
Vol 26 (24) ◽  
pp. 7416
Author(s):  
Ankhbayar Lkhagva ◽  
Hwan-Ching Tai

Metabolomics profiling using liquid chromatography-mass spectrometry (LC-MS) has become an important tool in biomedical research. However, resolving enantiomers still represents a significant challenge in the metabolomics study of complex samples. Here, we introduced N,N-dimethyl-l-cysteine (dimethylcysteine, DiCys), a chiral thiol, for the o-phthalaldehyde (OPA) derivatization of enantiomeric amine metabolites. We took interest in DiCys because of its potential for multiplex isotope-tagged quantification. Here, we characterized the usefulness of DiCys in reversed-phase LC-MS analyses of chiral metabolites, compared against five commonly used chiral thiols: N-acetyl-l-cysteine (NAC); N-acetyl-d-penicillamine (NAP); isobutyryl-l-cysteine (IBLC); N-(tert-butoxycarbonyl)-l-cysteine methyl ester (NBC); and N-(tert-butylthiocarbamoyl)-l-cysteine ethyl ester (BTCC). DiCys and IBLC showed the best overall performance in terms of chiral separation, fluorescence intensity, and ionization efficiency. For chiral separation of amino acids, DiCys/OPA also outperformed Marfey’s reagents: 1-fluoro-2-4-dinitrophenyl-5-l-valine amide (FDVA) and 1-fluoro-2-4-dinitrophenyl-5-l-alanine amide (FDAA). As proof of principle, we compared DiCys and IBLC for detecting chiral metabolites in aqueous extracts of rice. By LC–MS analyses, both methods detected twenty proteinogenic l-amino acids and seven d-amino acids (Ala, Arg, Lys, Phe, Ser, Tyr, and Val), but DiCys showed better analyte separation. We conclude that DiCys/OPA is an excellent amine-derivatization method for enantiomeric metabolite detection in LC-MS analyses.


Separations ◽  
2021 ◽  
Vol 8 (12) ◽  
pp. 232
Author(s):  
Petra Pojmanová ◽  
Nikola Ladislavová ◽  
Štěpán Urban

Every human body is a source of a unique scent, which can be used for medical or forensic purposes. Human skin scent is a complex mixture of more or less volatile compounds with different chemical and physical properties, which often differ significantly in their concentrations. The most efficient technique for separating such complex samples is comprehensive two-dimensional gas chromatography (GC × GC). This work aimed to find the optimal arrangement of a two-dimensional chromatographic system and define a suitable chromatographic method for non-targeted analysis of human scent samples. Four different chromatographic columns (non-polar Rxi-5MS and TG-5HT, medium polar Rxi-17Sil MS and Rtx-200MS) and their different configurations were tested. The best system was the 30 m primary column Rtx-200MS (with the 2 m pre-column Rtx-200MS) and the 1 m secondary column TG-5HT in a reverse configuration. This system achieved the highest theoretical and conditional peak capacities, optimal resolution, and the lowest number of coelutions.


2021 ◽  
Vol 37 (12) ◽  
pp. 1092-1100
Author(s):  
Wilfrid Boireau ◽  
Céline Elie-Caille

Extracellular vesicles (EVs) originate from eukaryotic and prokaryotic cells and play a crucial role in intercellular communications. They are found in the environment of cells and tissues, and contribute to the complexity of different biological media, in particular biofluids. Due to their high diversity of cell origin, size range, concentration and composition, EVs offer some of the most important challenges in (pre-)analytical fields. To tackle these challenges, many works deal with the development and implementation of a wide variety of approaches, technologies and methodologies to enrich, isolate, quantify and characterize EVs and their subsets. Nevertheless, other components such as lipoproteins or viruses in complex samples, can interfere with EVs qualification, and make difficult, even today, to standardize biochemical and physical approaches for this purpose. The present chapter presents EVs and the mostly used technics for their isolation and characterization. Performances of methods in terms of resolution, discrimination, throughput and also ability to be or not applied in clinics, are also discussed.


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