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1.
Molecules ; 29(9)2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38731399

RESUMO

The antibacterial effects of a selection of volatile fatty acids (acetic, propionic, butyric, valeric, and caproic acids) relevant to anaerobic digestion were investigated at 1, 2 and 4 g/L. The antibacterial effects were characterised by the dynamics of Enterococcus faecalis NCTC 00775, Escherichia coli JCM 1649 and Klebsiella pneumoniae A17. Mesophilic anaerobic incubation to determine the minimum bactericidal concentration (MBC) and median lethal concentration of the VFAs was carried out in Luria Bertani broth at 37 °C for 48 h. Samples collected at times 0, 3, 6, 24 and 48 h were used to monitor bacterial kinetics and pH. VFAs at 4 g/L demonstrated the highest bactericidal effect (p < 0.05), while 1 g/L supported bacterial growth. The VFA cocktail was the most effective, while propionic acid was the least effective. Enterococcus faecalis NCTC 00775 was the most resistant strain with the VFAs MBC of 4 g/L, while Klebsiella pneumoniae A17 was the least resistant with the VFAs MBC of 2 g/L. Allowing a 48 h incubation period led to more log decline in the bacterial numbers compared to earlier times. The VFA cocktail, valeric, and caproic acids at 4 g/L achieved elimination of the three bacteria strains, with over 7 log10 decrease within 48 h.


Assuntos
Antibacterianos , Enterococcus faecalis , Ácidos Graxos Voláteis , Klebsiella pneumoniae , Testes de Sensibilidade Microbiana , Ácidos Graxos Voláteis/metabolismo , Ácidos Graxos Voláteis/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/crescimento & desenvolvimento , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/crescimento & desenvolvimento , Anaerobiose , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Propionatos/farmacologia , Concentração de Íons de Hidrogênio , Ácidos Pentanoicos/farmacologia
2.
Adapt Phys Activ Q ; 41(4): 555-572, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38734418

RESUMO

This study sought to understand the lived experiences of wheelchair basketball athletes from low- and middle-income countries of recent or current armed conflict and the meaning that they ascribed to their participation. Wheelchair basketball athletes (N = 108) from eight national teams participated in semistructured focus-group interviews. Study data were analyzed thematically using an interpretive descriptive approach. Three themes were developed: "I can do anything I want; not only basketball," self-concept changes through sport participation; "Now they see me as a respectable person," societal belonging through sport; and "I have motivated other disabled people," influence on nonparticipating disabled persons. The findings indicated that participation in wheelchair sports may help disabled persons see themselves as capable individuals on the court and in aspects of daily living, perhaps even peer role models for other disabled persons in their communities and countries.


Assuntos
Conflitos Armados , Basquetebol , Pessoas com Deficiência , Grupos Focais , Cadeiras de Rodas , Humanos , Masculino , Feminino , Adulto , Esportes para Pessoas com Deficiência , Autoimagem , Pesquisa Qualitativa , Pessoa de Meia-Idade , Motivação , Adulto Jovem , Atletas/psicologia
3.
Cell Biol Toxicol ; 39(5): 2311-2329, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-35877023

RESUMO

In dose-response and structure-activity studies, human hepatic HepG2 cells were exposed for 3 days to nano Cu, nano CuO or CuCl2 (ions) at doses between 0.1 and 30 ug/ml (approximately the no observable adverse effect level to a high degree of cytotoxicity). Various biochemical parameters were then evaluated to study cytotoxicity, cell growth, hepatic function, and oxidative stress. With nano Cu and nano CuO, few indications of cytotoxicity were observed between 0.1 and 3 ug/ml. In respect to dose, lactate dehydrogenase and aspartate transaminase were the most sensitive cytotoxicity parameters. The next most responsive parameters were alanine aminotransferase, glutathione reductase, glucose 6-phosphate dehydrogenase, and protein concentration. The medium responsive parameters were superoxide dismutase, gamma glutamyltranspeptidase, total bilirubin, and microalbumin. The parameters glutathione peroxidase, glutathione reductase, and protein were all altered by nano Cu and nano CuO but not by CuCl2 exposures. Our chief observations were (1) significant decreases in glucose 6-phosphate dehydrogenase and glutathione reductase was observed at doses below the doses that show high cytotoxicity, (2) even high cytotoxicity did not induce large changes in some study parameters (e.g., alkaline phosphatase, catalase, microalbumin, total bilirubin, thioredoxin reductase, and triglycerides), (3) even though many significant biochemical effects happen only at doses showing varying degrees of cytotoxicity, it was not clear that cytotoxicity alone caused all of the observed significant biochemical effects, and (4) the decreased glucose 6-phosphate dehydrogenase and glutathione reductase support the view that oxidative stress is a main toxicity pathway of CuCl2 and Cu-containing nanomaterials.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Nanoestruturas , Humanos , Cobre/toxicidade , Células Hep G2 , Glutationa Redutase/metabolismo , Glutationa Redutase/farmacologia , Estresse Oxidativo , Nanoestruturas/toxicidade , Bilirrubina/metabolismo , Bilirrubina/farmacologia , Fosfatos/farmacologia , Glucose
4.
Environ Res ; 236(Pt 1): 116725, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37487922

RESUMO

The objectives of this study were to assess the role of soil organic matter on retaining plastic additives, Di(2-ethylhexyl) phthalate (DEHP), Bisphenol A (BPA) and Benzophenone (BP), to postulate the retention mechanisms and mobility in soil. Batch experiments were conducted for red yellow podzolic soil (OM) and soil subjected to high temperature oxidation at 600 °C for 2 h to remove total organic matter (OMR). Pristine soil, which contains organic matter abbreviated as OM (soil with organic matter) whereas total organic matter removed soil is abbreviated as OMR (organic matter removed soil). The pH edge and kinetic experiments were conducted with 20 g/L soil suspension spiked with 10 mg/L of each additive, whereas 1-20 mg/L concentration range was used in isotherm experiments and analyzed using high performance liquid chromatography. DEHP demonstrated the highest retention, 331 and 615.16 mg/kg in OM and OMR soils respectively, at pH 6.6. However, BPA and BP showed highest retentions of 132 and 128 mg/kg, respectively around pH 4.3 in pristine soil. DEHP interaction with soil OM indicated weak physical bonding whereas chemisorption to OMR soil. In the case of BPA, physisorption governed its interaction with both soil organic matter and mineral fraction. Nevertheless, BP demonstrated chemical interactions with OM and minerals. Desorption of DEHP was close to 100% however, BPA and BP were <15%. Overall, DEHP and BPA could be easily released into soil water and possibly be available for plant uptake while, BP is immobilized in soil.


Assuntos
Dietilexilftalato , Ácidos Ftálicos , Poluentes do Solo , Dietilexilftalato/análise , Solo/química , Poluentes do Solo/análise , Benzofenonas/análise
5.
Nucleic Acids Res ; 49(16): 9117-9131, 2021 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-34417596

RESUMO

Unequivocal functional assessment of candidate genomic regulatory regions, such as transcriptional response elements, requires genetic alteration at their native chromosomal loci. Targeted DNA cleavage by Cas9 or other programmable nucleases enables analysis at virtually any genomic region, and diverse alleles generated by editing can be defined by deep sequencing for functional analysis. Interpretation of disrupted response elements, however, presents a special challenge, as these regions typically comprise clustered DNA binding motifs for multiple transcriptional regulatory factors (TFs); DNA sequence differences, natural or engineered, that affect binding by one TF can confer loss or gain of binding sites for other TFs. To address these and other analytical complexities, we created three computational tools that together integrate, in a single experiment, allele definition and TF binding motif evaluation for up to 9216 clones isolated, sequenced and propagated from Cas9-treated cell populations. We demonstrate 1) the capacity to functionally assess edited TF binding sites to query response element function, and 2) the efficacy and utility of these tools, by analyzing cell populations targeted by Cas9 for disruption of example glucocorticoid receptor (GR) binding motifs near FKBP5, a GR-regulated gene in the human adenocarcinoma cell line A549.


Assuntos
Alelos , Genômica/métodos , Elementos de Resposta , Análise de Sequência de DNA/métodos , Células A549 , Edição de Genes , Humanos , Motivos de Nucleotídeos , Software , Proteínas de Ligação a Tacrolimo/genética , Fatores de Transcrição/metabolismo
6.
Matern Child Health J ; 25(3): 471-478, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33196924

RESUMO

INTRODUCTION: Moderate to vigorous physical activity (MVPA) is associated with positive physical and psychological health outcomes, yet youth with visual impairments tend to not to engage in sufficient MVPA. The purposes of this study were to (a) examine how familial factors were associated with MVPA among youth with visual impairments, their siblings, and parents and (b) examine the daily MVPA correlation among these family members. METHODS: Twenty-two familial triads, including one child with a visual impairment, participated in this study. Accelerometers were used to measure MVPA and individual and familial factors were reported via questionnaire. RESULTS: Of the individual and familial factors measured, only family member role significantly predicted MVPA (ß = .43, p < .01), as parents accumulated significantly more activity than their children (f2 = .22). The MVPA of children with visual impairments and their siblings were positively correlated (r = .39), while small negative relationships were found between MVPA of parents and children with and without visual impairments (r = - .16; r = - .33, respectively). DISCUSSION: In contrast with earlier findings, parents in the current study were significantly more active than their children with or without visual impairments. Potential reasons for this difference included the homogeneity of the sample, including a relatively high mean income level and parent education, which may have alleviated some typically reported barriers to parental MVPA. Future inquiries in this area should examine individual- and family-level factors concurrently to better understand their impact on MVPA within the familial triad.


Assuntos
Exercício Físico , Irmãos , Acelerometria , Adolescente , Criança , Humanos , Pais , Inquéritos e Questionários , Transtornos da Visão
7.
Adapt Phys Activ Q ; 38(2): 286-306, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33631720

RESUMO

The purpose of this inquiry was to examine the relationship between barriers to physical activity, expectancy-value variables, and physical activity engagement among adults with visual impairments. Using a descriptive correlational approach, a sample of 214 adults with visual impairments (Mage = 43.14, SD = 13.67) completed questionnaires pertaining to barriers to physical activity, expectancy-value beliefs about physical activity, and physical activity engagement. Data were analyzed via correlation and hierarchical regression. The final regression model explained 20.30% of variance in physical activity (p < .001). Intrinsic value (ß = 0.26, p = .01) and expectancy beliefs (ß = 0.33, p < .001) each emerged as significant predictors of physical activity engagement, which suggests that expectancy-value theory may have some utility for investigating the physical activity engagement of individuals with visual impairments. However, the lack of significant contribution of other variables such as attainment and utility values, as well as barriers factors, underscores the need for additional research in this area.


Assuntos
Exercício Físico , Motivação , Adulto , Humanos , Inquéritos e Questionários , Transtornos da Visão
8.
J Microsc ; 275(3): 159-171, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31292960

RESUMO

The surface of articular cartilage plays a crucial role in attenuating and transmitting mechanical loads in synovial joints to facilitate painless locomotion. Disruption to the surface of articular cartilage causes changes to its frictional properties instigating the deterioration of the tissue. In this study, we physically peeled the most superficial layer, a transparent membrane of 20.0 ± 4.7 µm thick, from the central loading region of femoral condyles of sheep. The ultrastructure of this layer without interference from the underlying cartilage was independently investigated using confocal, second harmonic generation and atomic force microscopy. We found that the most superficial layer contains chondrocytes, densely packed collagen, coarse elastic fibres and a fine elastic network. The elastic fibres are most prevalent at the surface of the layer, where collagen and chondrocyte densities are lowest. At the interface of this most superficial layer with the underlying bulk cartilage, a dense fibrillar network exists, formed mainly by collagen fibrils and elastin microfibrils. By contrast, the interface of the underlying cartilage with the most superficial layer contains collagen fibrils, fine microfibrils and microfibrils distinctively laced on one side. The findings of this study will play an important role in understanding the mechanical function and wear resistance of articular cartilage, and in developing more promising tissue engineering techniques to treat cartilage defects and osteoarthritis. LAY DESCRIPTION: The chronic pain and dysfuction in synovial joints caused by osteoarthritis can have a debilitating impact on daily activities for sufferers. Osteoarthritis is characterised by the deterioration of the articular cartilage. Despite intensive research, the wear mechanism of articular cartilage and the progression of osteoarthritis remain unclear in the literature. Articular cartilage is a resilient tissue that provides a low friction surface to facilitate painless locomotion. The surface of articular cartilage plays a crucial role in attenuating and transmitting mechanical loads. Disruption at the surface of articular cartilage causes changes to its frictional properties, instigating the deterioration of the tissue. Despite this, the definition of the most superficial layer of articular cartilage, as well as its composition and microstructure, have endured a long history of debate, clouding our understanding of the early progression of osteoarthritis. In order to investigate the surface of articular cartilage independently from the underlying cartilage, we physically peeled a transparent membrane of 20.0 ± 4.7 µm thickness, the most superficial layer, from the central loading region of the femoral condyles of sheep. Using confocal, second harmonic generation and atomic force microscopy, we found that the most superficial layer contains cartilage cells (chondrocytes), densely packed collagen, coarse elastic fibres and a fine elastic network. The coarse elastic fibres are most prevalent at the surface of the layer where collagen and chondrocyte densities are lowest. Furthermore, we investigated the surfaces at the interface of the most superficial layer with the underlying articular cartilage. At the interface of this most superficial layer with the underlying bulk cartilage, a dense fibrillar network exists, formed mainly by collagen fibrils and elastin microfibrils. In contrast, the interface of the underlying cartilage with the most superficial layer contains collagen fibrils, fine microfibrils and microfibrils distinctively laced on one side. The findings of this study have confirmed that there is a most superficial layer that is able to be removed using a tangential force. Through the application of advanced imaging technologies, we have shown that this most superficial layer is cellular and have detailed its composition and ultrastructure. Due to the close association between the form and function of tissues, the findings of this study will play an important role in understanding the mechanical function and wear mechanism of articular cartilage. This may lead to the development of more promising tissue engineering techniques to treat cartilage defects and osteoarthritis.


Assuntos
Cartilagem Articular/ultraestrutura , Processamento de Imagem Assistida por Computador/métodos , Microscopia de Força Atômica/métodos , Microscopia Confocal/métodos , Animais , Cartilagem Articular/anatomia & histologia , Condrócitos/ultraestrutura , Colágeno/ultraestrutura , Elastina/ultraestrutura , Microfibrilas/ultraestrutura , Ovinos
9.
Cell Biol Toxicol ; 35(2): 129-145, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30368635

RESUMO

The potential mammalian hepatotoxicity of nanomaterials was explored in dose-response and structure-activity studies in human hepatic HepG2 cells exposed to between 10 and 1000 µg/ml of five different CeO2, three SiO2, and one TiO2-based particles for 3 days. Various biochemical parameters were then evaluated to study cytotoxicity, cell growth, hepatic function, and oxidative stress. Few indications of cytotoxicity were observed between 10 and 30 µg/ml. In the 100 to 300 µg/ml exposure range, a moderate degree of cytotoxicity was often observed. At 1000 µg/ml exposures, all but TiO2 showed a high degree of cytotoxicity. Cytotoxicity per se did not seem to fully explain the observed patterns of biochemical parameters. Four nanomaterials (all three SiO2) decreased glucose 6-phosphate dehydrogenase activity with some significant decreases observed at 30 µg/ml. In the range of 100 to 1000 µg/ml, the activities of glutathione reductase (by all three SiO2) and glutathione peroxidase were decreased by some nanomaterials. Decreased glutathione concentration was also found after exposure to four nanomaterials (all three nano SiO2 particles). In this study, the more responsive and informative assays were glucose 6-phosphate dehydrogenase, glutathione reductase, superoxide dismutase, lactate dehydrogenase, and aspartate transaminase. In this study, there were six factors that contribute to oxidative stress observed in nanomaterials exposed to hepatocytes (decreased glutathione content, reduced glucose 6-phosphate dehydrogenase, glutathione reductase, glutathione peroxidase, superoxide dismutase, and increased catalase activities). With respect to structure-activity, nanomaterials of SiO2 were more effective than CeO2 in reducing glutathione content, glucose 6-phosphate dehydrogenase, glutathione reductase, and superoxide dismutase activities.


Assuntos
Cério/toxicidade , Fígado/efeitos dos fármacos , Nanoestruturas/toxicidade , Dióxido de Silício/toxicidade , Titânio/toxicidade , Proliferação de Células/efeitos dos fármacos , Citotoxinas/toxicidade , Células Hep G2 , Humanos , Fígado/enzimologia , Testes de Função Hepática , Estresse Oxidativo , Testes de Toxicidade/métodos
10.
Sleep Breath ; 23(1): 65-75, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29691799

RESUMO

PURPOSE: Obstructive sleep apnea (OSA) is the most commonly seen clinical sleep disorder. STOP-Bang, a widely used screening tool, yields a composite score based on eight dichotomized items including male gender. This study was designed to validate STOP-Bang among clinically referred patients and tested alternative scoring designs on tool performance, with a focus on gender differences in OSA. METHOD: STOP-Bang was administered to 403 female and 532 male subjects, followed by comprehensive sleep evaluation that included measurement of apnea-hypopnea indexes. Gender differences in STOP-Bang scores, OSA diagnosis, and severities were explored, and gender-specific alternative score cutoffs evaluated. Optimal operating points (OOP) were tested for female body mass index (BMI) and male neck circumference to inform STOP-Bang threshold refinement. Receiver operating characteristic curves were used to compare conventional and modified STOP-Bang. RESULTS: STOP-Bang performance by gender showed extremely low specificity in males at the recommended cutoff of ≥3. Better utility was presented at a cutoff of 4 or 5 among clinically referred patients irrespective of gender differences. Screening performance was improved by modifying BMI and/or neck circumference thresholds using gender-triaged OOP estimation. Three gender-based model revisions outperformed conventional STOP-Bang. CONCLUSION: Our study suggests that gender-specific consideration needs to be incorporated into the application of STOP-Bang in a clinically referred patient population with a higher risk of OSA. Alternative scoring systems may improve predictive performance of STOP-Bang.


Assuntos
Programas de Rastreamento/normas , Índice de Gravidade de Doença , Apneia Obstrutiva do Sono/diagnóstico , Adulto , Idoso , Índice de Massa Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polissonografia , Fatores Sexuais , Inquéritos e Questionários/normas
11.
J Environ Manage ; 251: 109512, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31563052

RESUMO

The Chinese Government is working to establish an effective framework in managing soil contamination. Heavy metal contamination is key to the discussion about soil quality, health and remediation in China. Soil heavy metal contamination in China is briefly reviewed and the concepts of background values and standards discussed. The importance of contaminated land and its management for China food security and urbanization are discussed. Priorities for China's next steps in developing an effective research and management regime are presented. We propose that critically important to the science-based risk assessment of contaminants in soils is the incorporation of speciation and bioavailability into the measurement and evaluation criteria. Consideration of soil biology/ecological endpoints will be necessary to protect ecosystem health. National and regional/local scenarios of land use type/usage will address residential/urban re-use of industrial land as well as varying agricultural scenarios.


Assuntos
Metais Pesados , Poluentes do Solo , China , Ecossistema , Monitoramento Ambiental , Solo
12.
Anal Chem ; 90(19): 11703-11709, 2018 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-30134659

RESUMO

The fate and behavior of polycyclic aromatic hydrocarbons (PAHs) in soil are of interest in the risk assessment of contaminated land and are usually based on determinations of fractions extracted from soil. For decades, either single- or sequential-solvent extractions have been used to determine PAH extractability in soils; however, there is a lack of certainty as to which fractions are being extracted by these techniques. This study is the first report of differences and similarities in the extractability of benzo[ a]pyrene (B[ a]P) in four contrasting soils (sandy loam, loamy sand, clayey loam, and sandy) when determined using both single-solvent (dichloromethane/acetone (DCM/Ace) mixture) and sequential-solvent (butanol followed by DCM/Ace) extraction. Residues after extraction were subjected to methanolic saponification (MeKOH). Butanol (BuOH) extractability and total extractability of B[ a]P following sequential-solvent extraction decreased significantly ( p < 0.05) with time after addition of B[ a]P. The decrease in BuOH extractability was particularly marked in the organic-matter-rich clayey-loam soil, which also had the largest (>40%) amounts of nonextractable residues. The cumulative amounts of B[ a]P extracted in each soil by single- and sequential-solvent extractions were similar ( p > 0.05) at each aging period, which indicated access to similar B[ a]P fractions in soil by both solvent extractions. The similarities in the amounts of B[ a]P nonextractable residues recovered by MeKOH from pre-extracted soils, through either of the extraction methods, confirms that the total extractable B[ a]P fractions from both methods are similar.

13.
Anal Chem ; 90(21): 13104-13111, 2018 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-30269489

RESUMO

The fate, impacts, and significance of polycyclic aromatic hydrocarbon (PAH) nonextractable residues (NERs) in soils remain largely unexplored in risk-based contaminated land management. In this study, seven different methanolic and nonmethanolic alkaline treatments, and the conventional methanolic saponification, were used to extract benzo[ a]pyrene (B[ a]P) NERs that had been aged for 180 d from four contrasting soils. Up to 16% and 55% of the amount of B[ a]P spiked (50 mg/kg) into soils was nonextractable after 2 d and 180 of aging, respectively, indicating rapid and progressive B[ a]P sequestration in soils over time. The recovery of B[ a]P from soils after 180 d of aging was increased by up to 48% by the seven different alkaline extractions, although the extraction efficiencies of the different alkaline treatments did not differ significantly ( p > 0.05). Approximately 40% of B[ a]P NERs in the sandy-clay-loam organic matter-rich soil was recovered by the exhaustive alkaline extractions after 180 d of aging, compared to only 10% using conventional methanolic saponification. However, the amounts of B[ a]P NERs recovered depend on soil properties and the amounts of NERs in soils. A significant correlation ( R2 = 0.69, p < 0.001) was also observed between the amounts of B[ a]P recovered by each of the seven alkaline extractions in the contrasting soils and corresponding NERs at 180 d of aging, indicating a potential association warranting further investigations. Extraction techniques that estimate the amounts of PAH NERs recoverable in soil can help give a better understanding of the fate of NERs in soil.

14.
Annu Rev Genet ; 44: 113-39, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20690856

RESUMO

Homologous recombination (HR) is required for accurate chromosome segregation during the first meiotic division and constitutes a key repair and tolerance pathway for complex DNA damage, including DNA double-strand breaks, interstrand crosslinks, and DNA gaps. In addition, recombination and replication are inextricably linked, as recombination recovers stalled and broken replication forks, enabling the evolution of larger genomes/replicons. Defects in recombination lead to genomic instability and elevated cancer predisposition, demonstrating a clear cellular need for recombination. However, recombination can also lead to genome rearrangements. Unrestrained recombination causes undesired endpoints (translocation, deletion, inversion) and the accumulation of toxic recombination intermediates. Evidently, HR must be carefully regulated to match specific cellular needs. Here, we review the factors and mechanistic stages of recombination that are subject to regulation and suggest that recombination achieves flexibility and robustness by proceeding through metastable, reversible intermediates.


Assuntos
Reparo do DNA , Recombinação Genética , Animais , Humanos , Leveduras/metabolismo
15.
Analyst ; 143(3): 768-776, 2018 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-29327006

RESUMO

Exposure to environmental insults generally occurs at low levels, making it challenging to measure bacterial responses to such interactions. Additionally, microbial behaviour and phenotype varies in differing bacterial types or growth phases, likely giving rise to growth- or species-specific responses to environmental stimuli. The present study applied a spectrochemical tool, infrared (IR) spectral interrogation coupled with multivariate analysis, to investigate the growth- and species-specific responses of two bacterial strains, Gram-negative Pseudomonas fluorescens and Gram-positive Mycobacterium vanbaalenii, to low concentrations of tetracycline, nanoparticulate silver (AgNP) or mixtures thereof. Results indicate the tendency for tetracycline-induced biospectral alterations to occur in outer-cellular components, e.g., phospholipids or proteins, while AgNPs-induced changes are mainly associated with proteins (∼964 cm-1, ∼1485 cm-1, ∼1550 cm-1, ∼1650 cm-1). The primary altered targets are correlated with bacterial membranes or outer-cellular components. Furthermore, significant lipid changes at 1705-1750 cm-1 were only present in P. fluorescens cells compared to M. vanbaalenii, owing to differences in cell wall structure between Gram-positive and -negative bacteria. This study also found distinct biospectral alterations in non-log phase compared to log phase, confirming bacterial growth-dependent responses to environmental exposures. It implies that previous studies on log phase only may underestimate the impacts from exposures of interest in situ, where bacteria stay in different growth stages. Our work proves the feasibility of biospectroscopy in determining bacterial responses to low-level environmental exposures in a fast and efficient manner, revealing sufficient biochemical information continuously through growth phases. As a nondestructive approach, biospectroscopy may provide deeper insights into the actual and in situ interactions between microbes and environmental stimuli, regardless of the exposure level, growth phase, or bacterial types.


Assuntos
Antibacterianos/farmacologia , Nanopartículas Metálicas , Mycobacterium/efeitos dos fármacos , Pseudomonas fluorescens/efeitos dos fármacos , Prata/farmacologia , Tetraciclina/farmacologia , Exposição Ambiental , Espectroscopia de Infravermelho com Transformada de Fourier
16.
Environ Sci Technol ; 52(21): 12295-12305, 2018 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-30351040

RESUMO

The environmental and health risks associated with "nonextractable" residues (NERs) of polycyclic aromatic hydrocarbons in soils and their potential for remobilization remain largely unexplored. In this novel study, sequential solvent extractions were employed to interrogate time-dependent remobilization of benzo[a]pyrene (B[a]P) NERs and associated kinetics after re-equilibration (REQ) periods lasting 30 d in four artificially spiked soils aged for up to 200 days. Following sequential extractions of the re-equilibrated soils, remobilization of B[a]P NERs was observed and further confirmed by decreases in the absolute amounts of B[a]P recovered following methanolic saponification after REQ. Remobilization may occur through slow intercompartmental partitioning of more sequestered into less sequestered B[a]P fractions in soils. The amounts of B[a]P remobilized in soils decreased throughout aging following first-order kinetics, and the rates of decrease were slow but 2 to 4 times faster than those of extractable B[a]P before re-equilibration. Sandy-clay-loam soils with large amounts of hard organic carbon exhibited less NER remobilization compared to sandy soils. The amounts of remobilized B[a]P decreased significantly ( p < 0.05) with aging. Specifically, butanol-remobilized B[a]P in soils spiked at 10 mg/kg and 50 mg/kg B[a]P ranged from 0.15 to 0.39 mg/kg and 0.67 to 2.30 mg/kg, respectively, after 200 d of aging.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Poluentes do Solo , Benzo(a)pireno , Solo , Microbiologia do Solo
17.
Am J Emerg Med ; 36(7): 1202-1208, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29291988

RESUMO

BACKGROUND: A multidisciplinary team at a major academic medical center established an Acutely Decompensated Heart Failure Clinical Pathway (ADHFCP) program to reduce inpatient readmission rates among patients with heart failure which, among several interventions, included an immediate consultation from a cardiologist familiar with an ADHFCP patient when the patient presented at the Emergency Department (ED). This study analyzed how that program impacted utilization of services in the ED and its subsequent effect on rates of admission from the ED and on disposition times. METHODS: ADHFCP inpatient visits were retrospectively risk stratified and matched with non-program inpatient visits to create a control group. A Cox survival model analyzed the ADHFCP's impact on patients' likelihood to visit the ED. Multivariable ANOVA evaluated the impact of the program on the patients' likelihood of being admitted when presenting at the ED. The ADHFCP's impact on bed-to-disposition time in the ED was evaluated by Wilcoxon's rank-sum test, as were doses of diuretics administered in the ED. RESULTS: The survival analysis showed no impact of the ADHFCP on patients' likelihood of visiting the ED, but ADHFCP patients presenting to the ED were 13.1 (95% CI: 3.6-22.6) percentage points less likely to be admitted. There was no difference in bed-to-disposition times, but ADHFCP patients received diuretics more frequently and at higher doses. CONCLUSIONS: Improved communication between cardiologists and ED physicians through the establishment of an explicit pathway to coordinate the care of heart failure patients may decrease that population's likelihood of admission without increasing ED disposition times.


Assuntos
Procedimentos Clínicos , Insuficiência Cardíaca/terapia , Idoso , Estudos de Casos e Controles , Comunicação , Intervalo Livre de Doença , Serviço Hospitalar de Emergência/estatística & dados numéricos , Utilização de Instalações e Serviços , Feminino , Nível de Saúde , Insuficiência Cardíaca/mortalidade , Hospitalização/estatística & dados numéricos , Humanos , Relações Interprofissionais , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
18.
Ecotoxicol Environ Saf ; 147: 594-601, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28923724

RESUMO

When aromatic hydrocarbons are present in contaminated soils, they often occur in mixtures. The impact of four different (3-ring) nitrogen-containing polycyclic aromatic hydrocarbons (N-PAHs) on 12/14C-phenanthrene and 12/14C-benzo[a]pyrene (B[a]P) mineralisation in soil was investigated over a 90 d incubation period. The results revealed that both 12/14C-phenanthrene and 12/14C-benzo[a]pyrene showed no significant mineralisation in soils amended with 10mgkg -1 and 100mgkg -1 N-PAHs (p>0.05). However, increases in lag-phases and decreases in the rates and extents of mineralisation were observed, over time. Among the N-PAHs, benzo[h]quinoline impacted 14C-phenanthrene mineralisation with extended and diauxic lag phases. Furthermore,12/14C-B[a]P and 14C-benzo[a]pyrene-nitrogen-containing polycyclic aromatic hydrocarbons (14C-B[a]P-N-PAHs) amended soils showed extensive lag phases (> 21 d); with some 14C-B[a]P-N-PAH mineralisation recording <1% in both concentrations (10mgkg -1 and 100mgkg -1), over time. This study suggests that the presence of N-PAHs in contaminated soil may impact the microbial degradation of polycyclic aromatic hydrocarbons (PAHs) and the impact was most likely the result of limited success in achieving absolute biodegradation of some PAHs in soil.


Assuntos
Benzo(a)pireno/análise , Nitrogênio/análise , Fenantrenos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Microbiologia do Solo , Poluentes do Solo/análise , Solo/química , Benzo(a)pireno/metabolismo , Biodegradação Ambiental , Monitoramento Ambiental , Fenantrenos/metabolismo , Reino Unido
19.
Adapt Phys Activ Q ; : 1-19, 2018 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-30562474

RESUMO

The theory of planned behavior is a psychological framework designed to examine the relationship between beliefs and volitional behaviors such as physical activity engagement. The purpose of this article was to evaluate the published empirical literature on the use of the theory of planned behavior in the context of physical activity beliefs and behaviors of individuals with disabilities. Electronic-database searches were conducted to identify relevant articles published between 1990 and 2018, yielding 11 articles that met all criteria for inclusion. Data such as population, measures, research design, and results were extracted from qualifying studies. Article quality was addressed using modified versions of the National Institutes of Health's Quality Assessment Tools. In keeping with the theory of planned behavior model, major findings indicate that intention to be physically active has the strongest relationship with physical activity behavior, while the predictive usefulness of belief factors was mixed, among individuals with disabilities.

20.
Adapt Phys Activ Q ; 35(2): 196-213, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29529866

RESUMO

The purpose of this study was to adopt an explicitly intersectional approach to examine the embodied perspectives of males with visual impairments about physical education. An interpretative phenomenological analysis research approach was used, and six adults (18-33 years) who identified as males with visual impairments acted as participants. The primary sources of data were semistructured, audiotaped, telephone interviews and reflective field notes. Thematic development utilized a four-step interpretative phenomenological analysis-guided analytical process. Based on the data analysis, the following three interrelated themes emerged: (a) "I didn't feel very integrated": Noninclusionary experiences based on blindness; (b) "Oh great, where's my cane now?": Bullying, blindness, and maleness; and (c) "Okay, just do what you can": Competitive culture glass ceiling. The themes highlight several issues that have been faced by males with visual impairments, which should be considered by physical education and adapted physical education personnel to enhance the quality of education for this population.


Assuntos
Atitude , Masculinidade , Educação Física e Treinamento , Transtornos da Visão/psicologia , Adolescente , Adulto , Humanos , Entrevistas como Assunto , Masculino , Pesquisa Qualitativa , Adulto Jovem
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