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1.
Front Chem ; 11: 1084046, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37065825

RESUMO

Surface-modified porous silica is a well-established composite material. To improve its embedding and application behavior, adsorption studies of various probe molecules have been performed using the technique of inverse gas chromatography (IGC). For this purpose, IGC experiments were carried out in the infinite dilution mode on macro-porous micro glass spheres before and after surface modification with (3-mercaptopropyl)trimethoxysilane. To provide information about the polar interactions between probe molecules and the silica surface, in particular, eleven polar molecules have been injected. In summary, the free surface energy for pristine silica ( γ S t o t a l = 229 mJ/m2) and for (3-mercaptopropyl)trimethoxysilane-modified silica ( γ S t o t a l = 135 mJ/m2) indicates a reduced wettability after surface modification. This is due to the reduction of the polar component of the free surface energy ( γ S S P ) from 191 mJ/m2 to 105 mJ/m2. Simultaneously, with the reduction of surface silanol groups caused by surface modification of silica and, therefore, the decrease in polar interactions, a substantial loss of Lewis acidity was observed by various IGC approaches. Experiments with all silica materials have been conducted at temperatures in the range from 90°C to 120°C to determine the thermodynamic parameters, such as adsorption enthalpy ( Δ H a d s ) and adsorption entropy ( Δ S a d s ), using the Arrhenius regression procedure evaluating the IGC data. With the help of the enthalpy-entropy compensation, two types of adsorption complexes are assumed between polar probe molecules and the silica surface because of different isokinetic temperatures. Identical adsorption complexes with an isokinetic temperature of 370°C have been assigned to alkanes and weakly interacting polar probes such as benzene, toluene, dichloromethane, and chloroform. Polar probe molecules with typical functional groups such as OH, CO, and CN, having the ability to form hydrogen bonds to the silica surface, exhibit a lower isokinetic temperature of 60°C. Quantum chemical calculations of the probe molecules on a non-hydroxylated and hydroxylated silica cluster supported the formation of hydrogen bonds in the case of a strong polar adsorption complex with a bonding distance of 1.7 nm-1.9 nm to the silica surface.

2.
J Psychiatr Res ; 138: 393-403, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33962126

RESUMO

Internet Gaming Disorder (IGD), describes the abuse of Internet games with detrimental impact to the real-life social engagement of some gamers. Indeed, evidence suggests that gamers differ on the severity and way in which they express IGD symptoms, as well as their social engagement behaviours. The present study aimed to: a) profile gamers regarding their experience of IGD symptoms and; b) examine how different IGD profiles varied on social engagement behaviours. METHODS: A sample consisting of 1032 gamers (18-72 years, Mage = 24) was assessed with the Internet Gaming Disorder Scale 9 Items Short Form (IGDS9-SF) and social engagement questions regarding their participation in employment, education, romantic relationships and living status. RESULTS: Latent class analyses (LCA) resulted in 4 distinct IGD classes. These entailed 'IGD aversive' (11.5%), 'Normative' (47.9%), 'Moderate IGD risk' (31.2%) and 'High IGD risk' (9.4%) gamers. The high IGD risk profile linked with higher unemployment, lower level of education and tended to live with divorced parents, friends and/or had transient accommodation. CONCLUSION: Findings suggest that there are different IGD profiles driven by symptom severity, whilst gamers higher on IGD risk present with lower social engagement signs. Thus, social engagement and participation should be particularly targeted by IGD immunization and treatment protocols.


Assuntos
Comportamento Aditivo , Jogos de Vídeo , Comportamento Aditivo/epidemiologia , Escolaridade , Humanos , Internet , Transtorno de Adição à Internet , Participação Social
3.
Clin Psychol Rev ; 77: 101831, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32143109

RESUMO

The inclusion of gaming disorder (GD) as an official diagnosis in the ICD-11 was a significant milestone for the field. However, the optimal measurement approaches for GD are currently unclear. This comprehensive systematic review aimed to identify and evaluate all available English-language GD tools and their corresponding evidence. A search of PsychINFO, PsychArticles, ScienceDirect, Scopus, Web of Science, and Google Scholar identified 32 tools employed in 320 studies (N = 462,249 participants). The evaluation framework examined tools in relation to: (1) conceptual and practical considerations; (2) alignment with DSM-5 and ICD-11 criteria; (3) type and quantity of studies and samples; and (4) psychometric properties. The evaluation showed that GD instrumentation has proliferated, with 2.5 tools, on average, published annually since 2013. Coverage of DSM-5 and ICD-11 criteria was inconsistent, especially for the criterion of continued use despite harm. Tools converge on the importance of screening for impaired control over gaming and functional impairment. Overall, no single tool was found to be clearly superior, but the AICA-Sgaming, GAS-7, IGDT-10, IGDS9-SF, and Lemmens IGD-9 scales had greater evidential support for their psychometric properties. The GD field would benefit from a standard international tool to identify gaming-related harms across the spectrum of maladaptive gaming behaviors.


Assuntos
Comportamento Aditivo/diagnóstico , Escalas de Graduação Psiquiátrica , Psicometria , Jogos de Vídeo , Humanos , Escalas de Graduação Psiquiátrica/normas , Psicometria/normas
4.
Dev Med Child Neurol ; 60(7): 636, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29676047
6.
Vet Parasitol ; 212(3-4): 105-10, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26315128

RESUMO

Bovine venereal trichomonosis caused by the flagellate Tritrichomonas foetus is a notifiable disease in Australia. While, T. foetus is pathogenic in both cattle and cats, it has long been established that the same T. foetus colonises the stomach, caecum and nasal cavity of pigs without apparent clinical significance. Multi-locus genotyping grouped the non-pathogenic porcine T. foetus with the pathogenic 'bovine genotype', rather than with the 'feline genotype' T. foetus. Bovine trichomonosis is now uncommon due to wide-spread use of artificial insemination, however, whether T. foetus remains prevalent in pigs where bovine trichomonosis has been eradicated remains unknown. We surveyed faecal samples from pigs farmed in close proximity with T. foetus-negative cattle. The Modified Diamond's Medium assay used were 77.4% (24/31) positive for trichomonads and 64.50% (20/31) were T. foetus-positive based on real-time PCR and conventional PCR. An axenic reference strain of T. foetus, designated PIG30/1 was established. In addition, a novel trichomonad ITS rDNA, PIG12, closely related to sequences from Trichomitus spp is reported. Multi-locus genotyping at nine loci matched PIG30/1 to the 'bovine genotype' T. foetus. In conclusion, cross-species transmission of T. foetus between pigs and cows from environmental exposure of T. foetus-contaminated pig faeces is unlikely. Domestic T. foetus-positive pigs possess a negligible risk of a successful T. foetus transmission event to cattle.


Assuntos
Doenças dos Bovinos/parasitologia , Fezes/parasitologia , Genótipo , Infecções Protozoárias em Animais/parasitologia , Doenças dos Suínos/parasitologia , Tritrichomonas foetus/genética , Animais , Bovinos , Tipagem de Sequências Multilocus , Suínos , Tritrichomonas foetus/isolamento & purificação
7.
Vet Parasitol ; 212(3-4): 111-7, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26315127

RESUMO

Tritrichomonas foetus was described as a commensal of the stomach, caecum and nasal cavity of pigs before it was recognised as the cause of reproductive tract disease of cattle. T. foetus also causes chronic large bowel diarrhoea in domestic cats. Multi-locus genotyping and comparative transcriptome analysis has previously revealed that T. foetus isolated from cat and cattle hosts are genetically distinct, referred to as the 'feline genotype' and 'bovine genotype', respectively. Conversely, multi-locus genotyping has grouped porcine T. foetus with the 'bovine genotype'. To compare the extent of the similarity between porcine T. foetus and cattle 'bovine genotype' isolates, RNA-sequencing (RNA-seq) was used to produce the first cell-wide transcriptome library of porcine T. foetus PIG30/1. Comparative transcriptome analysis of the PIG30/1 with the published bovine (BP-4) and feline (G10/1) transcriptomes revealed that the porcine T. foetus shares a 4.7 fold greater number of orthologous genes with the bovine T. foetus than with the feline T. foetus. Comparing transcription of the virulence factors, cysteine proteases (CP) between the three isolates, the porcine T. foetus was found to preferentially transcribe CP8 like the 'bovine genotype' T. foetus, compared to thehigh transcription of CP7 seen for 'feline genotype' T. foetus. At the cell-wide transcriptome level, the porcine T. foetus isolate (PIG30/1) groups closer with the 'bovine genotype' T. foetus rather than the 'feline genotype' T. foetus.


Assuntos
Doenças dos Bovinos/parasitologia , Infecções Protozoárias em Animais/parasitologia , RNA de Protozoário/genética , Doenças dos Suínos/parasitologia , Tritrichomonas foetus/genética , Animais , Bovinos , Cisteína Proteases/genética , Cisteína Proteases/metabolismo , Regulação Enzimológica da Expressão Gênica/fisiologia , Suínos
8.
Am J Respir Crit Care Med ; 192(3): 295-306, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26020495

RESUMO

RATIONALE: Little is known about the role of physical activity in the course of chronic obstructive pulmonary disease (COPD). OBJECTIVES: To assess changes in physical activity in COPD in relation to severity stages and changes in other disease components, and to evaluate the longitudinal association between sustained physical inactivity and disease progression. METHODS: In this prospective cohort study, we measured physical activity (multisensory armband), airflow obstruction (FEV1), health status (St. George's Respiratory Questionnaire), exercise capacity (6-min-walk distance [6MWD]), muscle mass (fat-free mass [FFM]), and systemic inflammation (fibrinogen and high-sensitivity C-reactive protein) over a 3-year period in 137 patients with COPD and 26 with chronic bronchitis (normal spirometry). MEASUREMENTS AND MAIN RESULTS: Independent of baseline disease severity, steps per day, total daily energy expenditure, and (daily) physical activity level (PAL) decreased by 393, 76 kcal, and 0.04 per year, respectively. The decline in PAL was significantly associated with a decline in FEV1 and an increase in St. George's Respiratory Questionnaire total score. Changes in 6MWD, FFM, and inflammatory markers were not associated with changes in PAL. Independent of FEV1, sustained physical inactivity (i.e., PAL(T0andT1) < 1.40) was related to a greater decline in 6MWD and FFM compared with that in patients with some level of activity (i.e., PAL(T0and/orT1) ≥ 1.40; difference, 17 m/yr and 0.87 kg/yr, respectively). CONCLUSIONS: Over time, physical activity substantially decreases across all severity stages of COPD, and this decline is paralleled by a worsening of lung function and health status. Sustained physical inactivity is associated with a progression of exercise intolerance and muscle depletion.


Assuntos
Exercício Físico , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Análise de Variância , Bronquite Crônica/fisiopatologia , Estudos de Coortes , Progressão da Doença , Metabolismo Energético , Feminino , Volume Expiratório Forçado , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/fisiopatologia , Estudos Prospectivos , Índice de Gravidade de Doença , Inquéritos e Questionários
9.
Am J Physiol Lung Cell Mol Physiol ; 306(6): L552-65, 2014 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-24487392

RESUMO

Reprogramming somatic cells to induced pluripotent stem cells (iPSCs) eliminates many epigenetic modifications that characterize differentiated cells. In this study, we tested whether functional differences between chronic obstructive pulmonary disease (COPD) and non-COPD fibroblasts could be reduced utilizing this approach. Primary fibroblasts from non-COPD and COPD patients were reprogrammed to iPSCs. Reprogrammed iPSCs were positive for oct3/4, nanog, and sox2, formed embryoid bodies in vitro, and induced teratomas in nonobese diabetic/severe combined immunodeficient mice. Reprogrammed iPSCs were then differentiated into fibroblasts (non-COPD-i and COPD-i) and were assessed either functionally by chemotaxis and gel contraction or for gene expression by microarrays and compared with their corresponding primary fibroblasts. Primary COPD fibroblasts contracted three-dimensional collagen gels and migrated toward fibronectin less robustly than non-COPD fibroblasts. In contrast, redifferentiated fibroblasts from iPSCs derived from the non-COPD and COPD fibroblasts were similar in response in both functional assays. Microarray analysis identified 1,881 genes that were differentially expressed between primary COPD and non-COPD fibroblasts, with 605 genes differing by more than twofold. After redifferentiation, 112 genes were differentially expressed between COPD-i and non-COPD-i with only three genes by more than twofold. Similar findings were observed with microRNA (miRNA) expression: 56 miRNAs were differentially expressed between non-COPD and COPD primary cells; after redifferentiation, only 3 miRNAs were differentially expressed between non-COPD-i and COPD-i fibroblasts. Interestingly, of the 605 genes that were differentially expressed between COPD and non-COPD fibroblasts, 293 genes were changed toward control after redifferentiation. In conclusion, functional and epigenetic alterations of COPD fibroblasts can be reprogrammed through formation of iPSCs.


Assuntos
Reprogramação Celular/genética , Fibroblastos/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Doença Pulmonar Obstrutiva Crônica/metabolismo , Idoso , Animais , Diferenciação Celular , Movimento Celular , Células Cultivadas , Colágeno/metabolismo , Feminino , Fibroblastos/citologia , Fibronectinas/metabolismo , Proteínas de Homeodomínio/metabolismo , Humanos , Masculino , Mesoderma , Camundongos , Camundongos Endogâmicos NOD , MicroRNAs/biossíntese , MicroRNAs/genética , Pessoa de Meia-Idade , Proteína Homeobox Nanog , Fator 3 de Transcrição de Octâmero/metabolismo , RNA Mensageiro/genética , Fatores de Transcrição SOXB1/metabolismo , Teratoma
10.
Proc Natl Acad Sci U S A ; 106(23): 9465-70, 2009 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-19458249

RESUMO

To examine the role of the visual thalamus in perception, we recorded neural activity in the lateral geniculate nucleus (LGN) and pulvinar of 2 macaque monkeys during a visual illusion that induced the intermittent perceptual suppression of a bright luminance patch. Neural responses were sorted on the basis of the trial-to-trial visibility of the stimulus, as reported by the animals. We found that neurons in the dorsal and ventral pulvinar, but not the LGN, showed changes in spiking rate according to stimulus visibility. Passive viewing control sessions showed such modulation to be independent of the monkeys' active report. Perceptual suppression was also accompanied by a marked drop in low-frequency power (9-30 Hz) of the local field potential (LFP) throughout the visual thalamus, but this modulation was not observed during passive viewing. Our findings demonstrate that visual responses of pulvinar neurons reflect the perceptual awareness of a stimulus, while those of LGN neurons do not.


Assuntos
Macaca mulatta/fisiologia , Pulvinar/fisiologia , Percepção Visual , Animais , Atenção , Mapeamento Encefálico , Neurônios/fisiologia , Pulvinar/citologia
11.
Am J Respir Crit Care Med ; 178(3): 248-60, 2008 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-18467512

RESUMO

RATIONALE: Fibroblasts are believed to be the major cells responsible for the production and maintenance of extracellular matrix. Alterations in fibroblast functional capacity, therefore, could play a role in the pathogenesis of pulmonary emphysema, which is characterized by inadequate maintenance of tissue structure. OBJECTIVES: To evaluate the hypothesis that deficient fibroblast repair characterizes cells obtained from individuals with chronic obstructive pulmonary disease (COPD) compared with control subjects. METHODS: Fibroblasts were cultured from lung tissue obtained from individuals undergoing thoracotomy and were characterized in vitro. MEASUREMENTS AND MAIN RESULTS: Fibroblasts from individuals with COPD, defined by reduced FEV(1), manifested reduced chemotaxis toward fibronectin and reduced contraction of three-dimensional collagen gels, two bioassays associated with fibroblast repair function. At least two mechanisms appear to account for these differences. Prostaglandin E (PGE), a known inhibitor of fibroblast repair functions, was produced in increased amount by fibroblasts from subjects with COPD, which also expressed increased amounts of the receptors EP2 and EP4, both of which signal through cyclic AMP. Incubation of fibroblasts with indomethacin or with the PKA inhibitor KT-5720 partially restored COPD subject fibroblast function. In addition, fibroblasts from subjects with COPD produced more transforming growth factor (TGF)-beta1, but manifested reduced response to TGF-beta1. The functional alterations in fibroblasts correlated with both lung function assessed by FEV(1) and, for the data available, with severity of emphysema assessed by Dl(CO). CONCLUSIONS: Fibroblasts from individuals with COPD have reduced capability to sustain tissue repair, which suggests that this may be one mechanism that contributes to the development of emphysema.


Assuntos
Quimiotaxia/fisiologia , Matriz Extracelular/metabolismo , Fibroblastos/metabolismo , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Idoso , Estudos de Casos e Controles , Células Cultivadas , Dinoprostona/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fator de Crescimento Transformador beta1/metabolismo
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