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1.
Entropy (Basel) ; 26(2)2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38392398

RESUMO

This research offers a solution to a highly recognized and controversial problem within the composite indicator literature: sub-indicators weighting. The research proposes a novel hybrid weighting method that maximizes the discriminating power of the composite indicator with objectively defined weights. It considers the experts' uncertainty concerning the conceptual importance of sub-indicators in the multidimensional phenomenon, setting maximum and minimum weights (constraints) in the optimization function. The hybrid weighting scheme, known as the SAW-Max-Entropy method, avoids attributing weights that are incompatible with the multidimensional phenomenon's theoretical framework. At the same time, it reduces the influence of assessment errors and judgment biases on composite indicator scores. The research results show that the SAW-Max-Entropy weighting scheme achieves greater discriminating power than weighting schemes based on the Entropy Index, Expert Opinion, and Equal Weights. The SAW-Max-Entropy method has high application potential due to the increasing use of composite indicators across diverse areas of knowledge. Additionally, the method represents a robust response to the challenge of constructing composite indicators with superior discriminating power.

2.
Res Sports Med ; : 1-12, 2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35861190

RESUMO

This study aims to investigate the fear or failure (FoF) in Brazilian runners of both sex, performance levels and age categories, as well as to verify the relationship between FoF and socioeconomic status (SES). Sample size as composed by 916. Age, sex, body height, body weight, SES, and running pace were self-reported. The Multidimensional Questionnaire of FoF was applied in an online platform. Running pace, and SES were categorized and processed through multivariate analysis and Spearman correlations, with the p-value set at 0.05. Female runners with better performance (2.13 ± 0.74) and younger (2.16 ± 0.80), as a well as male runners with worse performance (2.04 ± 0.69) and older (2.04 ± 0.89) presented the highest values of FoF. Among women, SES was negatively associated with FoF (r = -0.144; p = 0.006), while a positive association between running pace and SES was observed among men (r = 0.290; p < 0.001). Non-professional Brazilian runners presented low values of FoF.

3.
Biochem Cell Biol ; 93(6): 581-6, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26393781

RESUMO

Glycosphingolipids (GSLs) are hybrid molecules consisting of the sphingolipid ceramide linked to a mono- or oligo-saccharide. In comparison to other membrane lipids, the family of GSLs stands out because of the extensive variation in the carbohydrate headgroup. GSLs are cell surface binding partners, in cis with growth factor receptors, and in trans with bacterial toxins and viruses, and are among the host-derived membrane components of viral particles, including those of HIV. In spite of their biological relevance, GSL profiles of commonly used cell lines have been analyzed to different degrees. Here, we directly compare the GSL complements from CHO-K1, COS-7, HeLa, HEK-293, HEPG2, Jurkat, and SH-SY5Y cells using an HPLC-based method requiring modest amounts of material. Compared to previous studies, the HPLC-based analyses provided more detailed information on the complexity of the cellular GSL complement, qualitatively as well as quantitatively. In particular for cells expressing multiple GSLs, we found higher numbers of GSL species, and different levels of abundance. Our study thus extends our knowledge of biologically relevant lipids in widely used cell lines.


Assuntos
Membrana Celular/metabolismo , Glicoesfingolipídeos/metabolismo , Animais , Linhagem Celular , Linhagem Celular Tumoral , Membrana Celular/química , Células Cultivadas , Chlorocebus aethiops , Cromatografia Líquida de Alta Pressão , Cricetulus , Corantes Fluorescentes/química , Glicosídeo Hidrolases/metabolismo , Glicoesfingolipídeos/química , Hirudo medicinalis/enzimologia , Humanos , Hidrólise , Metabolômica/métodos , Camundongos , Microtecnologia/métodos , Estrutura Molecular , Ratos , Espectrometria de Fluorescência , ortoaminobenzoatos/química
4.
J Proteome Res ; 13(12): 6001-12, 2014 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-25384094

RESUMO

Protein precipitation in organic solvent is an effective strategy to deplete sodium dodecyl sulfate (SDS) ahead of MS analysis. Here we evaluate the recovery of membrane and water-soluble proteins through precipitation with chloroform/methanol/water or with acetone (80%). With each solvent system, membrane protein recovery was greater than 90%, which was generally higher than that of cytosolic proteins. With few exceptions, residual supernatant proteins detected by MS were also detected in the precipitation pellet, having higher MS signal intensity in the pellet fraction. Following precipitation, we present a novel strategy for the quantitative resolubilization of proteins in an MS-compatible solvent system. The pellet is incubated at -20 °C in 80% formic acid/water and then diluted 10-fold with water. Membrane protein recovery matches that of sonication of the pellet in 1% SDS. The resolubilized proteins are stable at room temperature, with no observed formylation as is typical of proteins suspended in formic acid at room temperature. The protocol is applied to the molecular weight determination of membrane proteins from a GELFrEE-fractionated sample of Escherichia coli proteins.


Assuntos
Temperatura Baixa , Formiatos/química , Espectrometria de Massas/métodos , Proteínas de Membrana/análise , Acetona/química , Membrana Celular/metabolismo , Clorofórmio/química , Cromatografia Líquida/métodos , Citosol/metabolismo , Eletroforese em Gel de Poliacrilamida , Proteínas de Escherichia coli/análise , Proteínas de Escherichia coli/química , Precipitação Fracionada/métodos , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Metanol/química , Peso Molecular , Proteoma/análise , Proteoma/química , Proteoma/metabolismo , Proteômica/métodos , Reprodutibilidade dos Testes , Solubilidade , Água/química
5.
Br J Sports Med ; 47(18): 1155-60, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24047570

RESUMO

BACKGROUND: Studies failing to show a negative effect of rapid weight loss (RWL) on performance have been conducted in athletes who have been cycling weight for years. It has been suggested that chronic weight cycling could lead combat athletes to become resistant to the stresses associated with weight loss. To investigate the effects of RWL up to 5% of body mass on high-intensity intermittent performance in weight cyclers (WC) and non-weight cyclers (non-WC). METHODS: Eighteen male combat athletes (WC: n=10; non-WC: n=8) reduced up to 5% of their body mass in 5 days. Body composition, high-intensity performance and plasma lactate were assessed preweight loss and postweight loss. Athletes had 4 h to re-feed and rehydrate following the weigh-in. Food intake was recorded during the weight loss and the recovery periods. RESULTS: Athletes significantly decreased body mass, lean body mass (most likely due to fluid loss) and fat mass following weight loss. No significant changes in performance were found from preweight loss to postweight loss in both groups. Plasma lactate was significantly elevated after exercise in both groups, but no differences were found between groups and in response to RWL. For all these variables no differences were observed between groups. Athletes from both groups ingested high amounts of energy and carbohydrates during the recovery period after the weigh-in. CONCLUSIONS: Chronic weight cycling does not protect athletes from the negative impact of RWL on performance. The time to recover after weigh-in and the patterns of food and fluid ingestion during this period is likely to play the major role in restoring performance to baseline levels.


Assuntos
Adaptação Fisiológica/fisiologia , Desempenho Atlético/fisiologia , Artes Marciais/fisiologia , Redução de Peso/fisiologia , Luta Romana/fisiologia , Adulto , Composição Corporal/fisiologia , Índice de Massa Corporal , Ingestão de Energia/fisiologia , Exercício Físico/fisiologia , Tolerância ao Exercício/fisiologia , Humanos , Ácido Láctico/sangue , Masculino , Adulto Jovem
6.
Front Psychol ; 14: 1134797, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37809282

RESUMO

Purpose: Our purpose was to investigate the interplay between runners and their environment using a network approach. Methods: This cross-sectional study sampled Brazilian runners of both sexes, from the five macro-regions of the country. An electronic questionnaire was used to obtain information regarding age, sex, training volume, socio-economic level, place of residence, and running pace. Environmental indicators (public illumination, pavement, sidewalk, and green areas) were collected from available public information. Descriptive statistics were presented in mean (SD), and frequency (%). A network analysis was performed to evaluate the association between individual and environmental characteristics. Statistical analyses were performed in the JASP, considering p < 0.05. Results: At North and Mid-West regions, public illumination presents the highest values for the expected influence (1.74 and 1.56), while in Northeast and Southeast, sidewalks present the highest values (2.13; 0.91). For betweenness centrality, in North, Northeast, and Mid-West regions, residency in the capital of a state presented a hub. In contrast, pavement, and training volume present higher values in the South and Southeast. Network topologies are different. Conclusion: Public illumination (North and Mid-West) and sidewalk (Northeast, Southeast) were the most important variables for runners. Continental size countries need specific approaches to improve physical activity levels and health outcomes that consider the cultural, historical, and environmental background.

7.
Artigo em Inglês | MEDLINE | ID: mdl-36767880

RESUMO

BACKGROUND: Studies with rural children are limited, and results are divergent regarding the information on movement behaviours. PURPOSE: to (i) describe the physical activity and sedentary behaviour in children; (ii) synthetize the year and place of publication, methodological quality, and instruments used to measure physical activity and sedentary behaviour; and (iii) to analyse the relationship between physical activity, sedentary behaviour, and health outcomes in these children. METHODS: We use the databases PubMed, Web of Science, SPORTDiscus, Scopus, Virtual Health Library, and SciELO, considering papers published until October 2021. A total of 12,196 studies were identified, and after the exclusion of duplicate, title and abstract screening, and the full-text assessment, a total of 68 were included in the study. RESULTS: A cross-sectional design was dominant among the studies, with sample sizes ranging from 23 to 44,631 children of both sexes. One-third of the studies were conducted in North America and Europe, and most of them used device-based measurements. Inequalities were observed regarding sex, age, economic level, race, and physical activity domains within and between the places of residence. Sociodemographic characteristics were also related to health outcomes for children living in rural and urban areas. CONCLUSION: It is necessary to increase the evidence on movement behaviours among children living in the countries of South America and Oceania, as well as to increase the level of evidence on the role of school for physical activity in children in rural areas, given the inconsistent findings.


Assuntos
Exercício Físico , Comportamento Sedentário , Masculino , Feminino , Humanos , Criança , Estudos Transversais , População Rural , Avaliação de Resultados em Cuidados de Saúde
8.
Front Psychol ; 14: 1135471, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37492448

RESUMO

Purpose: Our purpose was to verify the existence of birthplace and relative age effect (RAE), as well as the association between birthplace effect and RAE among Brazilian athletes competing in the Olympic Games. Methods: Data included information about Brazilian Summer Olympic athletes from 1920 to 2021. To investigate RAE, athletes' birthdate was distributed into birth quartiles (Q1: Jan-Mar; Q2: Apr-Jun; Q3: Jul-Sep; Q4: Oct-Dec), while birthplace effect was assessed considering the state and the region (Southeast; Northeast; South; North; and Midwest) of birth. The Chi-square test (χ2) was used to verify differences between the birthplace effect and RAE. Results: The sample consisted of 388 Brazilian athletes of both sexes, distributed in 38 sports modalities from 23 Brazilian states (Southeast = 66.5%; South = 14.4%; Northeast = 12.1%; North = 1.5%; Midwest = 5.4%). For both sexes, most of the athletes were from the São Paulo state (37.4%), followed by Rio de Janeiro (18.3%), both from the Southeast region. For birthdate distribution according to birthplace, it was observed that the North region presented the highest frequency of athletes born in Q1 (50%), followed by the Northeast and Southeast regions. No significant differences were found for the birthplace effect (χ2 = 5.69, value of p = 0.128) and RAE between sexes (χ2 = 0.530, value of p = 0.912), nor was shown an association between the birthplace effect and RAE. Conclusion: Most Brazilian Olympic athletes are from the Southeast region, but no RAE was established regarding their birthplace. Results from the present study can guide sports public policies in Brazilian regions, especially in the Midwest, North, and Northeast regions, which are underrepresented in Brazilian high-performance sports.

9.
Sports Med Open ; 9(1): 17, 2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36821018

RESUMO

BACKGROUND: Running participation/performance is a complex system. Understanding the variables associated with these behaviors may help to increase population physical activity and improve performance. This study aimed to investigate social and training variables important for running performance using a network approach. METHODS: This cross-sectional study sampled 1151 non-professional Brazilian runners of both sexes (women, 38.2%; men, 61.7%). A questionnaire was available for eligible participants using an online platform, and information regarding training (volume and running pace) and social variables (participation in a running event, participation in a running group, influence on running, runners in the family, and childhood sport) related to runners' performance was obtained. The Chi-square test and network model were estimated by sex. RESULTS: Training characteristics tend to be clustered. For both sexes, the training volume node presented the highest expected influence in the network (1.69 for women and 2.16 for men). Centrality indicators of social variables show that sports childhood participation and the presence of runners in the family were the most important nodes of network connection for women and men, respectively. CONCLUSION: Based on these findings, it was concluded that sports participation during childhood and the practice of running by other family members were important factors to connect variables in the network. These findings have practical applications for health policymakers, highlighting the need to develop educational programs to increase sports participation during childhood and within families.

10.
Sports Med Health Sci ; 5(4): 277-282, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38314049

RESUMO

This study aimed to investigate the trends of finishers in the São Silvestre race in Brazil, taking into account sex, age, and performance levels. A total of 31 â€‹775 runners (women, n â€‹= â€‹13 â€‹847; men, n â€‹= â€‹17 â€‹928), aged (45.2 â€‹± â€‹16.8) years, finishers in the São Silvestre race between 2007 and 2021, were considered in the present analysis. Data (event year, date of birth, sex, and race times) were downloaded from the official race website. The man-Whitney U test, Spearman correlation, and robust regression model were computed. Participation increased over time for both sexes. Regarding age groups, "31-40 years" (women) and "> 60 years" (men) were those with the highest number of finishers. We found a decrease in performance across the years (ߠ​= â€‹2.45; p â€‹< â€‹0.005), as well as significant differences in race times for both sexes (U â€‹= â€‹42.844; p â€‹< â€‹0.001), with men presenting better performances than women. Over time, it was observed an increase in the performance gap between the sexes, but in general, the performance decreased (ߠ​= â€‹1.76; p â€‹< â€‹0.001). Stakeholders should consider improving the strategies to improve women and young people's participation in running events.

11.
Animals (Basel) ; 13(19)2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37835638

RESUMO

An analog of a bovine-appeasing substance (BAS) was previously demonstrated to have calming effects, and it could be an alternative to alleviate the stress caused by weaning. Thus, the objective of this study was to evaluate the effects of BAS administration at weaning on growth, stress, behavior, and response to vaccination of Nellore calves. Eighty-six Nellore calves (40 females and 46 males) were abruptly weaned and randomly assigned into 1 of 2 treatments: (1) saline solution (0.9% NaCl; n = 43) and (2) BAS (Secure Catte, IRSEA Group, Quartier Salignan, France; n = 43). The solutions were topically applied (5 mL/calf) to the nuchal skin area of each animal. On d 0, before treatment application, calves were vaccinated against infectious bovine rhinotracheitis (IBR), parainfluenza-3 (PI3) virus, and bovine viral diarrhea virus types 1 and 2 (BVDV-1 and 2). Calves from each treatment were kept in different pastures for 15 d (time of BAS action) and then moved to a single pasture. Body weight (BW), blood samples, and temperament in the chute (entry score, chute score, and exit score) were collected on d 0, 3, 8, 15, 51, and 100, and behavior on pasture on d 1, 2, 4, 5, 6, 7, and 9. Calves assigned to BAS vs. Saline treatment tended to have greater BW on d 15 (p = 0.10), tended to have lower entry scores on d 8 and 51 (p = 0.10), and chute scores on d 8 (p = 0.07), and had lower exit scores on d 8 (p = 0.02). Calves assigned to BAS vs. Saline treatment also had greater time grazing on d 7 and 9 (p < 0.01), eating concentrate on d 2, 5, and 6 (p = 0.05), walking on d 1, 2, 5, and 9 (p < 0.01), standing and ruminating on d 2, 7 and 9 (p < 0.01), and playing on d 2, 4, 6, 7, and 9 (p < 0.01). Furthermore, they had lower time lying on 1 and 2 (p < 0.01), standing on d 5 and 9 (p < 0.01), and vocalizing on d 1 and 2 (p < 0.01). Calves assigned to BAS vs. Saline treatment had greater serum titter concentrations of PI3 t on d 15 and 51 (p = 0.05) and BVDV-1 on d 51 (p = 0.02). However, they had lower serum concentrations of cortisol on d 3 (p = 0.03). BAS administration did not affect (p ≥ 0.12) the serum titer concentration of IBR and BVDV-2 titers or the plasma concentration of haptoglobin and ceruloplasmin. The BAS administration improved BW, reduced temperament and serum cortisol concentration, and improved behavior and response to vaccination.

12.
Rapid Commun Mass Spectrom ; 26(5): 523-31, 2012 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-22302492

RESUMO

RATIONALE: Fluorinated surfactants are being explored as mass spectrometry (MS)-friendly alternatives to sodium dodecyl sulfate (SDS) for proteome analysis. Previous work demonstrates perfluorooctanoic acid (PFOA) to be compatible with electrospray ionization (ESI)-MS. The high volatility of PFOA provides an intrinsic approach to potentially eliminate the surfactant during ESI, or alternatively through solvent evaporation prior to MS. The ammonium salt of PFOA, ammonium perfluorooctanoate (APFO), is likely favored for proteome experiments; the MS and liquid chromatography (LC)/MS tolerance of APFO has not been established for proteome applications. METHODS: Standard proteins and peptides, as well as a yeast proteome mixture, were individually spiked with surfactants (APFO, PFOA, SDS), and subjected to direct infusion ESI-MS, LC/MS/MS and LC/UV. The level of fluorinated surfactant remaining after solvent evaporation under varying conditions (time, pH, salt and protein content) was quantified and compared to the threshold tolerance level of the surfactant in an MS experiment (determined herein). RESULTS: Whereas PFOA is found ineffective at assisting protein solubilization, APFO is as effective as SDS for resolubilization of acetone-precipitated yeast proteins (~100% recovery). Unfortunately, the LC and MS threshold tolerance of APFO is only minimally greater than SDS (~2-fold higher concentration to cause 50% suppression). Nonetheless, the benefits of APFO in a proteome experiment are realized following a one-step evaporation protocol for removal of the surfactant in acidified solvent. CONCLUSIONS: APFO is considered a favoured alternative to SDS for proteome solubilization. Strictly speaking, APFO is not an 'MS-friendly' surfactant for proteome characterization; the detergent not only suppresses ESI signals at high concentration, but also perturbs reversed phase separation. However, the simplicity of APFO removal ahead of LC/MS justifies its use over the conventional SDS.


Assuntos
Caprilatos/química , Fluorocarbonos/química , Proteoma/análise , Proteômica/métodos , Tensoativos/química , Espectrometria de Massas em Tandem/métodos , Compostos Orgânicos Voláteis/química , Peptídeos/análise , Proteínas/análise , Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/análise , Solubilidade , Espectrometria de Massas por Ionização por Electrospray/métodos
13.
Vet Parasitol Reg Stud Reports ; 34: 100769, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36041804

RESUMO

The infestation of Rhipicephalus microplus (Acari: Ixodidae) (Canestrini, 1887) represents a significant health problem for cattle. Up until today, no consistent control has been recommended for the free-living larval stage of R. microplus. The objective of the present study was to determine the larvicidal effect of an Allium sativum (garlic) aqueous extract against R. microplus using the larval package test, LPT. Tick larvae were obtained from adult female ticks from naturally infected animals, and 200 larvae were exposed to each A. sativum extract concentration (5, 7, 10, 16, 25, and 50%). All garlic groups received the extract in three different volumes (2, 5, and 7 ml) to determine the levels of humidity that would affect the free-living stage. Larvae from the control group were treated with distilled water and the positive control used cypermethrin in a 5-ml volume. Live and dead larvae were determined after 24 h of exposure. There was a significant statistical difference (P = 0.041) at 5% between 2 and 5 ml and between 7 and 10% of the extract using 2 ml (P = 0.034). There was a significant larvicidal activity of 100% mortality for the 16, 25, and 50% concentrations for all volumes. We observed a clear concentration-dependent effect for the extracts with a correlation coefficient of R2 > 0.92. The lethal concentration of 50% (LC50) was 13.6, 9.8, and 7.6% for the 2, 5, and 7 ml. The present A. sativum solutions may be considered a viable biofriendly alternative to reduce the number of the free-living larval stage of R. microplus on pasture and the consequent reduction of cattle infestation due to its high larval mortality.


Assuntos
Acaricidas , Alho , Rhipicephalus , Acaricidas/farmacologia , Animais , Bovinos , Feminino , Larva , Extratos Vegetais/farmacologia
14.
Aging Dis ; 13(5): 1413-1420, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36186143

RESUMO

Aging is a biological process, which is usually associated with health-related problems, which are related to some behaviours, such as those related to movement and eating habits. So, the purpose of the present study was to identify the clustering of behavioural and eating habits related to non-communicable disease in Brazilian elderly, and to estimate the association of these profiles with overweight/obesity, hypertension, and diabetes. This is a cross-sectional based-population study, which sample comes from the VIGITEL 2019 survey. The sample comprised 23,327 subjects (16,295 women), mean age of 71 years. Sociodemographic and anthropometric data (i.e., age, sex, body weight, and body height), health-related information (i.e., eating habits, physical activity and sedentary behaviour, and alcohol consumption), health status and morbidity (diabetes and hypertension) were self-reported. Latent Classes Analysis, and binary logistic regression were performed, considering p<0.05. Results showed that two different classes were identified. Those called as "TV viewer, but no unhealthy diet" presented more chances to have hypertension (OR: 1.213; 95%CI: 1.064-1.382) and diabetes (OR: 1.365; 95%CI: 1.157-1.610), when compared to their peers called as "healthy diet and active". Age, educational level, and sex were associated with hypertension and diabetes. In conclusion, a better health clustered-behaviour was associated with better disease outcomes in Brazilian elderly population.

15.
J Proteome Res ; 9(6): 2863-70, 2010 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-20377267

RESUMO

SDS has recognized benefits for protein sample preparation, including solubilization and imparting molecular weight separation (e.g., SDS-PAGE). Here, we compare two proteome workflows which incorporate SDS for protein separation, namely, SDS-PAGE coupled to LC/MS (GeLC MS), along with a solution separation platform, GELFrEE, for intact proteome prefractionation and identification. Despite the clear importance of SDS in these and other proteome analysis workflows, the affect of SDS on an LC/MS proteome experiment has not been quantified. We first examined the influence of SDS on both a bottom-up as well as a top-down (intact protein) MS workflow. Surprisingly, at levels up to 0.01% SDS in the injected sample, reliable MS characterization is obtained. We subsequently explored organic precipitation protocols (chloroform/methanol/water and acetone) as a means of lowering SDS, and present a simple modified acetone precipitation protocol which consistently enables MS proteome characterizations from samples initially containing 2% SDS. With this effective strategy for SDS reduction, the GELFrEE MS workflow for bottom-up proteome analysis was characterized relative to GeLC MS. Remarkable agreement in the number and type of identified proteins was obtained from these two separation platforms, validating the use of SDS in solution-phase proteome analysis.


Assuntos
Eletroforese em Gel de Poliacrilamida/métodos , Espectrometria de Massas/métodos , Proteínas/isolamento & purificação , Proteômica/métodos , Dodecilsulfato de Sódio/química , Precipitação Química , Cromatografia Líquida , Peso Molecular , Proteínas/análise , Proteínas/química , Proteoma/análise , Proteoma/química , Reprodutibilidade dos Testes
16.
J Mech Behav Biomed Mater ; 104: 103637, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32174395

RESUMO

OBJECTIVES: To compare the effects of replacing reinforcing barium glass particles by DCPD (dicalcium phosphate dihydrate), as opposed to simply reducing glass filler content, on composite flexural properties and degree of conversion (DC). On a second set of experiments, composites with different "DCPD: glass" ratios were exposed to prolonged water immersion to verify if the presence of DCPD particles increased hydrolytic degradation. METHODS: Two series of composites were prepared: 1) composites with total inorganic content of 50 vol% and "DCPD: glass" ratios ranging from zero (glass only) to 1.0 (DCPD only), in 0.25 increments, and 2) composites containing only silanized glass (from zero to 50 vol%). Disk-shaped specimens were fractured under biaxial flexural loading after 24 h in water. Another set of specimens of composites with different "DCPD: glass" ratios was stored in water for 24 h, 30, 60, 90 and 120 days and tested in flexure. DC was determined using FTIR spectroscopy. Data were analyzed using Kruskal-Wallis/Dunn test (flexural properties) or ANOVA/Tukey test (DC, alpha: 0.05). RESULTS: For glass-only composites, reducing inorganic content caused a linear decrease in strength. The presence of DCPD did not affect composite strength up until a "DCPD: glass" ratio of 0.5. On the other hand, materials with 0.75 and 1.0 DCPD showed significantly lower strength than the glass-only composite with 12.5 vol% filler and the unfilled resin, respectively (p < 0.001). Except for the 0.25 DCPD composite, the presence of DCPD did not contribute to increase flexural modulus. After water storage, composites containing DCPD showed higher percent reductions in properties than the control, but only in a few cases the effect was statistically significant (strength: 0.5 DCPD, modulus: 0.25 and 1.0 DCPD). DC was only marginally affected by DCPD fraction. SIGNIFICANCE: For composites with "DCPD: glass" of 0.25 and 0.5, reductions in strength were related to the lower glass content, and not due to the presence of DCPD. Flexural modulus was primarily defined by glass content. Overall, composites containing DCPD particles presented higher reductions in properties after water storage, but it remained within limits reported for commercial materials.


Assuntos
Cálcio , Resistência à Flexão , Resinas Compostas , Vidro , Teste de Materiais , Fosfatos , Maleabilidade , Propriedades de Superfície , Água
17.
Mater Sci Eng C Mater Biol Appl ; 116: 111178, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32806326

RESUMO

OBJECTIVES: To synthesize and characterize brushite particles in the presence of acidic monomers (acrylic acid/AA, citric acid/CA, and methacryloyloxyethyl phosphate/MOEP) and evaluate the effect of these particles on degree of conversion (DC), flexural strength/modulus (FS/FM) and ion release of experimental composites. METHODS: Particles were synthesized by co-precipitation with monomers added to the phosphate precursor solution and characterized for monomer content, size and morphology. Composites containing 20 vol% brushite and 40 vol% reinforcing glass were tested for DC, FS and FM (after 24 h and 60 d in water), and 60-day ion release. Data were subjected to ANOVA/Tukey tests (DC) or Kruskal-Wallis/Dunn tests (FS and FM, alpha: 5%). RESULTS: The presence of acidic monomers affected particle morphology. Monomer content on the particles was low (0.1-1.4% by mass). Composites presented similar DC. For FS/24 h, only the composite containing DCPD_AA was statistically similar to the composite containing 60 vol% of reinforcing glass (without brushite, "control"). After 60 days, all brushite-containing materials showed similar FS, statistically lower than the control composite (p<0.01). Composites containing DCPD_AA, DCPD_MOEP or DCPD_U ("unmodified") showed statistically similar FM/24 h, higher than the control composite. After prolonged immersion, all composites were similar to the control composite, except DCPD_AA. Cumulative ion release ranged from 21 ppm to 28 ppm (calcium) and 9 ppm to 17 ppm (phosphate). Statistically significant reductions in ion release between 15 and 60 days were detected only for the composite containing DCPD_MOEP. SIGNIFICANCE: Acidic monomers added to the synthesis affected brushite particle morphology. After 60-day storage in water, composite strength was similar among all brushite-containing composites. Ion release was sustained for 60 days and it was not affected by particle morphology.


Assuntos
Fosfatos de Cálcio , Resinas Compostas , Materiais Dentários , Resistência à Flexão , Teste de Materiais , Metacrilatos , Maleabilidade
18.
J Biomed Mater Res B Appl Biomater ; 107(3): 708-715, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30091514

RESUMO

This study describes the synthesis of dicalcium phosphate dihydrate (DCPD) particles in the presence of different ethylene glycol dimethacrylates (EGDMA, ethylene glycol/EG units: 1, 2, 3 or 4) at two monomer-to-ammonium phosphate molar ratios (1:1 and 2:1), as a strategy to develop CaP-monomer particles with improved interaction with resin matrices. Particles displaying high surface areas and organic contents were added to a photocurable BisGMA-TEGDMA resin and the resulting materials were tested for degree of conversion (DC), biaxial flexural strength (BFS), flexural modulus, and ion release. Data were subjected to one-way ANOVA or Kruskal-Wallis/Dunn test (alpha: 0.05). Functionalization with EGDMA derivatives was dependent upon the length of the spacer group and monomer concentration in the synthesis. No differences in DC were observed among materials (p > 0.05). A 39% increase in BFS was obtained with the use of particles with the highest functionalization level compared to non-functionalized particles (p < 0.001). The use of functionalized DCPD reduced flexural modulus in comparison to non-functionalized particles (p < 0.001). Calcium release was similar among materials and remained constant during the experiment, while phosphate release was higher at 7 days in comparison to the remaining weeks (p < 0.001). In conclusion, diethylene glycol dimethacrylate resulted in the highest functionalization levels and the highest BFS among DCPD-containing materials. Ion release was not affected by functionalization. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2018. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 708-715, 2019.


Assuntos
Fosfatos de Cálcio/química , Materiais Dentários/química , Teste de Materiais , Metacrilatos/química
19.
Rev Rene (Online) ; 25: e93082, 2024. tab, graf
Artigo em Português | LILACS-Express | LILACS, BDENF - enfermagem (Brasil) | ID: biblio-1565003

RESUMO

RESUMO Objetivo descrever a percepção dos coordenadores de saúde e educação quanto à operacionalização, potencialidades e fragilidades do Programa Estratégico de Fortificação da Alimentação Infantil com Micronutrientes em Pó. Métodos pesquisa qualitativa, abrangendo nove municípios que aderiram ao programa. A coleta de dados foi realizada por meio de um questionário semiestruturado com base no manual operacional do programa. Os depoimentos foram analisados à luz da análise de conteúdo. Resultados participaram 11 coordenadores. Os dados apontaram divergências quanto ao armazenamento inadequado dos sachês e ao intervalo entre os ciclos. Foram encontradas dificuldades na comunicação, envolvimento das equipes e rotatividade de profissionais. Conclusão evidenciou-se que ações direcionadas à alimentação infantil fortalecem os atributos da atenção primária à saúde e repercutem de forma positiva na identificação de grupos vulneráveis, para que se possa buscar a promoção de sua saúde e a prevenção de doenças. Contribuições para a prática: os resultados deste estudo podem contribuir no aperfeiçoamento da intersetorialidade e na problematização das dificuldades associadas, levando à ampliação do acesso às unidades básicas e estimulando as ações de promoção da alimentação adequada e saudável, bem como à organização da atenção nutricional.


ABSTRACT Objective to describe the perception of health and education coordinators regarding the operationalization, strengths, and weaknesses of a Strategic Program for the Fortification of Infant Foods with Micronutrient Powders. Methods qualitative search in nine municipalities that joined the program. Data collection was carried out using a semistructured questionnaire based on the operational manual of the program. Statements were analyzed considering content analysis. Results 11 coordinators participated. Data found suggests differences regarding inadequate storage of sachets and the interval between cycles. There were difficulties regarding communication, team involvement, and professional turnover. Conclusion actions associated with children diets are in accordance with primary health care attributes, having a positive impact on the identification of vulnerable groups, so we can seek health promotion and disease prevention. Contributions to practice: the results of this study can contribute to improve intersectoral work and raise questions about the difficulties associated with it, leading to an increased access to basic units and encouraging actions to promote adequate and healthy diets, in addition to organizing nutritional care.

20.
Artigo em Português | LILACS | ID: biblio-1528262

RESUMO

Este estudo analisou a relação entre indicadores de risco à saúde e as componentes do somatótipo consoante os níveis de atividade física em crianças. Trata-se de uma pesquisa epidemiológica de base escolar, composta por 168 crianças (6 a 11 anos) de ambos os sexos. Informações demográficas foram obtidas. Avaliações antropométricas (estatura; massa corporal; pregas de adiposidade subcutânea; perímetros do braço contraído, cintura, quadril e panturrilha), pressão arterial sistólica e diastólica, e atividade física (ativo; inativo) foram mensuradas. O somatótipo, razão cintura-quadril e razão cintura-estatura foram calculados. Análise de comparação, correlação e regressão linear múltipla foram realizadas, considerando intervalo de confiança de 95%. Meninos apresentaram maior número de passos, razão cintura-quadril e cintura-estatura. Crianças ativas eram mais velhas, possuíam maior perímetro de cintura, quadril e pressão arterial sistólica. No grupo fisicamente ativo, o sexo esteve associado diretamente ao perímetro de cintura e razão cintura-estatura, enquanto a idade associou-se com a perímetro de quadril e pressão arterial diastólica. Nas crianças inativas, todas as variáveis preditoras (exceto para a variável sexo em relação ao perímetro de quadril) mostraram-se significativas para o perímetro da cintura e quadril, explicando, conjuntamente, ~83% e 85% da expressão destas variáveis, respectivamente. A relação entre indicadores de risco à saúde e as componentes do somatótipo foi maior em crianças inativas. Independentemente do nível de atividade física, a endomorfia mostrou relação significativa com os componentes de saúde, com maior efeito no grupo inativo, tendo em vista a associação com a composição corporal dos sujeitos.


Este estudio analizó la relación entre indicadores de riesgo para la salud y los componentes del somatótipo según los niveles de actividad física en niños. Se trata de una investigación epidemiológica, compuesta por 168 niños (6 a 11 años) de ambos sexos. Fueron mensuradas: evaluaciones antropométricas (estatura; masa corporal; pliegues de adiposidad subcutánea; perímetros del brazo contraído, cintura, cuadril y pantorrilla), presión arterial sistólica y diastólica, y actividad física (activo/inactivo); el somatótipo, a través del cálculo de: razón cintura-cuadril y razón cintura-estatura. Se realizó el análisis de comparación, correlación y regresión lineal múltiple, considerando intervalo de confianza del 95%. Los niños presentaron mayor número de pasos, razón cintura-cuadril y cintura-estatura. Los niños activos eran mayores, tenían mayor perímetro de cintura, cuadril y presión arterial sistólica. En el grupo físicamente activo, el sexo estuvo asociado directamente al perímetro de cintura y razón cintura-estatura, mientras que la edad se asoció con el perímetro de cuadril y presión arterial diastólica. En los niños inactivos, todas las variables predictoras (excepto para la variable sexo con relación al perímetro de cuadril) se mostraron significativas para el perímetro de la cintura y cuadril, explicando, conjuntamente, ~83% y 85% de la expresión de estas variables, respectivamente. La relación entre indicadores de riesgo para la salud y los componentes del somatotipo fue mayor en niños inactivos. Independientemente del nivel de actividad física, la endomorfia mostró una relación significativa con los componentes de salud, con mayor efecto en el grupo inactivo, con vistas a la asociación con la composición corporal de los sujetos.


This study analysed the relationship between health risk indicators and somatotype components according to physical activity levels in children. This epidemiological and school-based research comprised 168 children of both sexes (56% boys), aged between 6 to 11 years. Demographic information (sex, age) was obtained. Anthropometric information (body height; body mass; contracted arm, waist, hip, and calf circumferences), body composition (subcutaneous adiposity and somatotype), systolic and diastolic blood pressure, and physical activity level (active; inactive) were measured. The waist-hip ratio and waist-to-height ratio were computed. Comparison, correlation, and multiple linear regression analysis were performed, considering 95% of the confidence interval. Boys presented higher values for physical activity, waist-hip, and waist-to-height ratio. Active children were older, had a larger waist and hip circumference, and higher systolic blood pressure. Among the active group, sex was associated with waist circumference and waist-to-height ratio, while age was associated with hip circumference and diastolic blood pressure. Among inactive children, all predictors (except for sex for hip circumference) were significantly associated with waist and hip circumferences, explaining ≅83% and 85% of the expression of these variables, respectively. The relationship between health risk indicators and somatotype components was higher among inactive children. Regardless of the physical activity level, the endomorphic component shows a significant relationship with health components, with a higher effect among the inactive group, considering the body composition association.


Assuntos
Humanos , Masculino , Feminino , Criança , Somatotipos , Exercício Físico , Fatores de Risco Cardiometabólico , Composição Corporal , Antropometria , Medição de Risco , Pressão Arterial
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