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1.
Sci Rep ; 14(1): 21603, 2024 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-39284901

RESUMO

This study investigates the impact of social media-related microbreaks on the resource recovery of employees. Specifically, we examined whether or not the brief, hedonic use of social media through algorithmic videos could fully replenish resources, such as vigor and fatigue, that are depleted after performing clerical tasks. We also compared this form of recovery to other established microbreak activities. We used a pre-registered, mixed-method experimental design to collect data from 308 employees. A series of mixed-method ANOVA tests complemented by quadratic linear contrast terms and post-hoc analyses were performed to test hypotheses and address research questions. The findings indicate that although social media microbreaks offer a certain degree of resource replenishment, they do not provide full recovery, particularly regarding fatigue. Social media facilitate a reasonable psychological detachment but fall short in other recovery experiences. Notably, exposure to nature yielded more beneficial results. The study contributes novel insights to a field primarily focused on the negative impacts of excessive social media use and suggests that rational and brief usage can be advantageous for employee well-being.


Assuntos
Mídias Sociais , Humanos , Masculino , Feminino , Adulto , Fadiga , Pessoa de Meia-Idade
2.
Ecotoxicol Environ Saf ; 272: 116033, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38335581

RESUMO

The baby disposable diapers were investigated as a sampling material for urine collection and validated for the evaluation of the exposure of children to xenobiotics. Phthalate metabolites detected in urine samples were chosen as proof-of-concept analytes. For the determination of phthalate metabolites in children's urine samples, high performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS) was used. Two sampling approaches were compared, namely sterile containers and baby disposable diapers. Thirty urine samples from infants and toddlers were analyzed by both methods in parallel and the results were compared. It was found that for diaper sampling, lower concentrations of the metabolites were observed, however, the general distribution for particular metabolites remains the same for both methods. For most of the metabolites high determination coefficients were obtained, namely 0.9929 for MEHHP, 0.9836 for MMP, 0.9796 for MECPP, and 0.9784 for 2-cx-MMHP. For MEOHP the determination correlation coefficient was 0.9154, while for MBP was - 0.7771 and MEHP was - 0.5228. In general, for diaper sampling an underestimation for 2-cx-MMHP and MEOHP was observed, while for MMP diaper-based approach provides overestimation. However, the proposed procedure confirms the possibility of using baby disposable diapers as a material for the collection of urine samples for biomonitoring purposes and fast screening of phthalates exposure.


Assuntos
Poluentes Ambientais , Ácidos Ftálicos , Lactente , Humanos , Espectrometria de Massas em Tandem , Coleta de Urina , Ácidos Ftálicos/urina , Exposição Ambiental/análise , Poluentes Ambientais/análise
3.
Molecules ; 27(20)2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36296639

RESUMO

Three porous matrices based on poly(lactic acid) are proposed herein for the controlled release of amikacin. The materials were fabricated by the method of spraying a surface liquid. Description is given as to the possibility of employing a modifier, such as a silica nanocarrier, for prolonging the release of amikacin, in addition to using chitosan to improve the properties of the materials, e.g., stability and sorption capacity. Depending on their actual composition, the materials exhibited varied efficacy for drug loading, as follows: 25.4 ± 2.2 µg/mg (matrices with 0.05% w/v of chitosan), 93 ± 13 µg/mg (with 0.08% w/v SiO2 amikacin modified nanoparticles), and 96 ± 34 µg/mg (matrices without functional additives). An in vitro study confirmed extended release of the drug (amikacin, over 60 days), carried out in accordance with the mathematical Kosmyer-Pepas model for all the materials tested. The matrices were also evaluated for their effectiveness in inhibiting the growth of bacteria such as Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa. Concurrent research was conducted on the transdermal absorption, morphology, elemental composition, and thermogravimetric properties of the released drug.


Assuntos
Amicacina , Quitosana , Amicacina/farmacologia , Dióxido de Silício , Porosidade , Preparações de Ação Retardada , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Pseudomonas aeruginosa , Escherichia coli
4.
Adv Med Sci ; 67(2): 269-282, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35841880

RESUMO

PURPOSE: Even in the 21st century, chronic wounds still pose a major challenge due to potentially inappropriate treatment options, so the latest wound dressings are hybrid systems that enable clinical management, such as a hybrid of hydrogels, antibiotics and polymers. These wound dressings are mainly used for chronic and complex wounds, which can easily be infected by bacteria. MATERIALS AND METHODS: Six Composite Porous Matrices (CPMs) based on polyurethane (PUR) in alliance with polylactide (PLAs) and poly(vinyl alcohol) (PVA) were prepared and analyzed using optical microscopy. Three different types of hydrogels and their Ciprofloxacin (Cipro) modified variants' ratios were prepared and analyzed using FTIR, SEM and EDX techniques. Six Hybrid Cipro-Releasing Hydrogel Wound Dressings (H-CRWDs) were also prepared and underwent short-term degradation, Cipro release, microbiology and cell viability measurements. RESULTS: Average porosity of CPMs was in the range of 69-81%. The pore size of the obtained CPMs was optimal for skin regeneration. Short-term degradation studies revealed degradability in physiological conditions regardless of sample type. A meaningful release was also observed even in short time (21.76 â€‹± â€‹0.64 â€‹µg/mL after 15 â€‹min). Microbiological tests showed visible inhibition zones. Cell viability tests proved that the obtained H-CRWDs were biocompatible (over 85% of cells). CONCLUSIONS: A promising hybrid wound dressing was labeled. Simple and cost-effective methods were used to obtain microbiologically active and biocompatible dressings. The results were of importance for the design and development of acceptable solutions in the management of chronic wounds of high potential for infection.


Assuntos
Ciprofloxacina , Poliuretanos , Ciprofloxacina/farmacologia , Poliuretanos/farmacologia , Álcool de Polivinil/farmacologia , Cicatrização , Bandagens , Hidrogéis/farmacologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Polímeros/farmacologia
5.
Materials (Basel) ; 14(20)2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34683646

RESUMO

This paper addresses the potential application of flexible thermoplastic polyurethane (TPU) and poly(lactic acid) (PLA) compositions as a material for the production of antibacterial wound dressings using the Fused Filament Fabrication (FFF) 3D printing method. On the market, there are medical-grade polyurethane filaments available, but few of them have properties required for the fabrication of wound dressings, such as flexibility and antibacterial effects. Thus, research aimed at the production, characterization and modification of filaments based on different TPU/PLA compositions was conducted. The combination of mechanical (tensile, hardness), structural (FTIR), microscopic (optical and SEM), degradation (2 M HCl, 5 M NaOH, and 0.1 M CoCl2 in 20% H2O2) and printability analysis allowed us to select the most promising composition for further antibacterial modification (COMP-7,5PLA). The thermal stability of the chosen antibiotic-amikacin-was tested using processing temperature and HPLC. Two routes were used for the antibacterial modification of the selected filament-post-processing modification (AMI-1) and modification during processing (AMI-2). The antibacterial activity and amikacin release profiles were studied. The postprocessing modification method turned out to be superior and suitable for wound dressing fabrication due to its proven antimicrobial activity against E. coli, P. fluorescens, S. aureus and S. epidermidis bacteria.

7.
Mol Pharm ; 18(8): 2986-2996, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34196555

RESUMO

The aim of this study was to fabricate novel microparticles (MPs) for efficient and long-term delivery of amikacin (AMI). The emulsification method proposed for encapsulating AMI employed low-molecular-weight poly(lactic acid) (PLA) and poly(lactic acid-co-polyethylene glycol) (PLA-PEG), both supplemented with poly(vinyl alcohol) (PVA). The diameters of the particles obtained were determined as less than 30 µm. Based on an in-vitro release study, it was proven that the MPs (both PLA/PVA- and PLA-PEG/PVA-based) demonstrated long-term AMI release (2 months), the kinetics of which adhered to the Korsmeyer-Peppas model. The loading efficiencies of AMI in the study were determined at the followings levels: 36.5 ± 1.5 µg/mg for the PLA-based MPs and 106 ± 32 µg/mg for the PLA-PEG-based MPs. These values were relatively high and draw parallels with studies published on the encapsulation of aminoglycosides. The MPs provided antimicrobial action against the Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae bacterial strains. The materials were also comprehensively characterized by the following methods: differential scanning calorimetry; gel permeation chromatography; scanning electron microscopy; Fourier transform infrared spectroscopy-attenuated total reflectance; energy-dispersive X-ray fluorescence; and Brunauer-Emmett-Teller surface area analysis. The findings of this study contribute toward discerning new means for conducting targeted therapy with polar, broad spectrum antibiotics.


Assuntos
Amicacina/administração & dosagem , Antibacterianos/administração & dosagem , Portadores de Fármacos/química , Composição de Medicamentos/métodos , Lactatos/química , Poliésteres/química , Polietilenoglicóis/química , Amicacina/química , Antibacterianos/química , Cápsulas , Liberação Controlada de Fármacos , Escherichia coli/efeitos dos fármacos , Klebsiella pneumoniae/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Peso Molecular , Tamanho da Partícula , Álcool de Polivinil/química , Pseudomonas aeruginosa/efeitos dos fármacos , Solubilidade , Staphylococcus aureus/efeitos dos fármacos
8.
Molecules ; 23(11)2018 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-30423814

RESUMO

Lignocellulosic biomass is an abundant and renewable resource that potentially contains large amounts of energy. It is an interesting alternative for fossil fuels, allowing the production of biofuels and other organic compounds. In this paper, a review devoted to the processing of lignocellulosic materials as substrates for fermentation processes is presented. The review focuses on physical, chemical, physicochemical, enzymatic, and microbiologic methods of biomass pretreatment. In addition to the evaluation of the mentioned methods, the aim of the paper is to understand the possibilities of the biomass pretreatment and their influence on the efficiency of biofuels and organic compounds production. The effects of different pretreatment methods on the lignocellulosic biomass structure are described along with a discussion of the benefits and drawbacks of each method, including the potential generation of inhibitory compounds for enzymatic hydrolysis, the effect on cellulose digestibility, the generation of compounds that are toxic for the environment, and energy and economic demand. The results of the investigations imply that only the stepwise pretreatment procedure may ensure effective fermentation of the lignocellulosic biomass. Pretreatment step is still a challenge for obtaining cost-effective and competitive technology for large-scale conversion of lignocellulosic biomass into fermentable sugars with low inhibitory concentration.


Assuntos
Fermentação , Lignina/química , Biocombustíveis , Biomassa , Hidrogênio , Hidrólise , Temperatura
9.
J AOAC Int ; 100(4): 922-934, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28623655

RESUMO

This paper concerns the possibility of using TLC coupled with a flame ionization detector (FID) and micro-TLC (µTLC) as precursors for microfluidized devices of analytical techniques to identify and determine the presence and content of the petroleum/vegetable oil base in the lubricating oils applied in cutting devices (chainsaws). This research is related to the problem of ensuring, in compliance with the requirements of environmental protection, a sufficient level of biodegradability of lubricating oils emitted to the environment during operation of equipment lubricated with these oils. Such oils include those mainly used in cutting devices and emitted in the form of a mist into the environment during the operation of those devices. When oil components are eco-toxic, contamination of the environment occurs. New methodologies for the identification and determination of the petroleum oil base, which is very difficult to biodegrade, as well as the easily biodegradable ingredients of vegetable origin in the lubricating oils, are presented. The described procedures indicate in an indisputable way whether the oil contains the oil base originating from crude oil and whether it contains adequate enriching additives. The procedures also allow the assessment of the content of particular groups of constituents (µTLC) or the determination of the group composition (TLC-FID).


Assuntos
Cromatografia/métodos , Ionização de Chama , Lubrificantes/análise , Óleos/análise , Petróleo/análise
10.
J Thromb Thrombolysis ; 40(2): 240-7, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25490871

RESUMO

Assessment of thromboembolic risk is crucial for proper management of atrial fibrillation (AF) patients. Currently used risk score base only on scarce clinical data and do not take into consideration parameters including echocardiographic findings. The aim of this study was to evaluate if left atrium (LA) enlargement is associated with higher thromboembolic risk assessed by CHADS2 and CHA2DS2-VASc scores in a cohort of unselected non-valvular AF patients. Data from 582 AF hospitalizations occurring between November 2012 and January 2014 were analyzed. All patients underwent a standard transthoracic echocardiography and had their thromboembolic risk assessed in both CHADS2 and CHA2DS2-VASc scores. In 494 enrolled patients (48.5 % male; mean age 73.4 ± 11.5 years) AF was classified as paroxysmal in 233 (47.3 %), as persistent in 109 (22.1 %), and as permanent in 151 (30.6 %) patients. LA was enlarged in 426 (86.2 %) patients. Enlargement was classified as mild in 99 (20.0 %) patients, as moderate in 130 (26.3 %) patients, and as severe in 196 (39.7 %) patients. Patients with enlarged LA had higher mean CHADS2 score (2.0 ± 1.5 vs. 2.6 ± 1.3; p = 0.0005) and CHA2DS2-VASc (3.8 ± 2.0 vs. 4.4 ± 1.8; p = 0.02) score than patients with normal LA. The both mean scores rose along with rising LA diameter. LA enlargement is highly prevalent in AF patients. Higher thromboembolic risk assessed by both CHADS2 and CHA2DS2-VASc scores is associated with presence of LA enlargement. Echocardiographically assessed LA size may be an additional parameter useful in thromboembolic risk stratification of AF patients.


Assuntos
Fibrilação Atrial/complicações , Fibrilação Atrial/fisiopatologia , Eletrocardiografia , Tromboembolia/etiologia , Tromboembolia/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Átrios do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
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