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1.
ACS Nano ; 17(20): 20053-20061, 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37797269

RESUMO

Controlling and understanding reaction temperature variations in catalytic processes are crucial for assessing the performance of a catalyst material. Local temperature measurements are challenging, however. Luminescence thermometry is a promising remote-sensing tool, but it is cross-sensitive to the optical properties of a sample and other external parameters. In this work, we measure spatial variations in the local temperature on the micrometer length scale during carbon dioxide (CO2) methanation over a TiO2-supported Ni catalyst and link them to variations in catalytic performance. We extract local temperatures from the temperature-dependent emission of Y2O3:Nd3+ particles, which are mixed with the CO2 methanation catalyst. Scanning, where a near-infrared laser locally excites the emitting Nd3+ ions, produces a temperature map with a micrometer pixel size. We first designed the Y2O3:Nd3+ particles for optimal temperature precision and characterized cross-sensitivity of the measured signal to parameters other than temperature, such as light absorption by the blackened sample due to coke deposition at elevated temperatures. Introducing reaction gases causes a local temperature increase of the catalyst of on average 6-25 K, increasing with the reactor set temperature in the range of 550-640 K. Pixel-to-pixel variations in the temperature increase show a standard deviation of up to 1.5 K, which are attributed to local variations in the catalytic reaction rate. Mapping and understanding such temperature variations are crucial for the optimization of overall catalyst performance on the nano- and macroscopic scale.

2.
Expert Opin Drug Saf ; 21(5): 699-706, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35060443

RESUMO

BACKGROUND: Systematically registering ADRs in electronic health records (EHRs) likely contribute to patient safety as it enables the exchange of drug safety data. Currently, ADRs registrations by healthcare professionals (HCPs) is suboptimal. This study aimed to identify barriers and facilitators perceived by HCPs to register ADRs systematically in EHRs. RESEARCH DESIGN AND METHODS: A qualitative study with individual interviews was conducted among specialist physicians and hospital pharmacists from 10 different Dutch hospitals. A semi-structured interview guide was used to identify experienced barriers and facilitators for systematically registering ADRs. Data was analyzed following thematic analysis. Themes within barriers and facilitators were aligned with the Capability-Opportunity-Motivation-Behavior (COM-B) framework. RESULTS: In total, 16 HCPs were interviewed. Identified barriers were: lack of knowledge to recognize ADRs, time constraints, inadequate IT system, lack of support, stuck in routine, and not recognizing the importance of registering ADRs. Identified facilitators were: enhanced knowledge and awareness of ADRs, functional IT systems, expanding accountability for registration, and motivation toward registering. CONCLUSIONS: Barriers and facilitators for registering spanned all aspects of the COM-B model and occurred in individual, social and environmental domains. Addressing these aspects could improve the registration of ADRs and may contribute to patient safety.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Registros Eletrônicos de Saúde , Atenção à Saúde , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Pessoal de Saúde , Humanos , Pesquisa Qualitativa
3.
Appl Environ Microbiol ; 84(11)2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29625974

RESUMO

The Cuatro Ciénegas Basin (CCB) is located in the Chihuahuan desert in the Mexican state of Coahuila; it has been characterized as a site with high biological diversity despite its extreme oligotrophic conditions. It has the greatest number of endemic species in North America, containing abundant living microbialites (including stromatolites and microbial mats) and diverse microbial communities. With the hypothesis that this high biodiversity and the geographic structure should be reflected in the virome, the viral communities in 11 different locations of three drainage systems, Churince, La Becerra, and Pozas Rojas, and in the intestinal contents of 3 different fish species, were analyzed for both eukaryotic and prokaryotic RNA and DNA viruses using next-generation sequencing methods. Double-stranded DNA (dsDNA) virus families were the most abundant (72.5% of reads), followed by single-stranded DNA (ssDNA) viruses (2.9%) and ssRNA and dsRNA virus families (0.5%). Thirteen families had dsDNA genomes, five had ssDNA, three had dsRNA, and 16 had ssRNA. A highly diverse viral community was found, with an ample range of hosts and a strong geographical structure, with very even distributions and signals of endemicity in the phylogenetic trees from several different virus families. The majority of viruses found were bacteriophages but eukaryotic viruses were also frequent, and the large diversity of viruses related to algae were a surprise, since algae are not evident in the previously analyzed aquatic systems of this ecosystem. Animal viruses were also frequently found, showing the large diversity of aquatic animals in this oasis, where plants, protozoa, and archaea are rare.IMPORTANCE In this study, we tested whether the high biodiversity and geographic structure of CCB is reflected in its virome. CCB is an extraordinarily biodiverse oasis in the Chihuahuan desert, where a previous virome study suggested that viruses had followed the marine ancestry of the marine bacteria and, as a result of their long isolation, became endemic to the site. In this study, which includes a larger sequencing coverage and water samples from other sites within the valley, we confirmed the high virus biodiversity and uniqueness as well as the strong biogeographical diversification of the CCB. In addition, we also analyzed fish intestinal contents, finding that each fish species eats different prey and, as a result, presents different viral compositions even if they coexist in the same pond. These facts highlight the high and novel virus diversity of CCB and its "lost world" status.


Assuntos
Bacteriófagos/classificação , Biodiversidade , Vírus de DNA/classificação , Peixes/virologia , Microbiota , Vírus de RNA/classificação , Animais , Bacteriófagos/isolamento & purificação , Vírus de DNA/isolamento & purificação , DNA Bacteriano/genética , Variação Genética , Geografia , Intestinos/virologia , México , Filogenia , Vírus de RNA/isolamento & purificação , RNA Ribossômico 16S/genética , Microbiologia da Água
4.
J Biol Chem ; 292(43): 17857-17875, 2017 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-28893907

RESUMO

Myosin A (MyoA) is a Class XIV myosin implicated in gliding motility and host cell and tissue invasion by malaria parasites. MyoA is part of a membrane-associated protein complex called the glideosome, which is essential for parasite motility and includes the MyoA light chain myosin tail domain-interacting protein (MTIP) and several glideosome-associated proteins (GAPs). However, most studies of MyoA have focused on single stages of the parasite life cycle. We examined MyoA expression throughout the Plasmodium berghei life cycle in both mammalian and insect hosts. In extracellular ookinetes, sporozoites, and merozoites, MyoA was located at the parasite periphery. In the sexual stages, zygote formation and initial ookinete differentiation precede MyoA synthesis and deposition, which occurred only in the developing protuberance. In developing intracellular asexual blood stages, MyoA was synthesized in mature schizonts and was located at the periphery of segmenting merozoites, where it remained throughout maturation, merozoite egress, and host cell invasion. Besides the known GAPs in the malaria parasite, the complex included GAP40, an additional myosin light chain designated essential light chain (ELC), and several other candidate components. This ELC bound the MyoA neck region adjacent to the MTIP-binding site, and both myosin light chains co-located to the glideosome. Co-expression of MyoA with its two light chains revealed that the presence of both light chains enhances MyoA-dependent actin motility. In conclusion, we have established a system to study the interplay and function of the three glideosome components, enabling the assessment of inhibitors that target this motor complex to block host cell invasion.


Assuntos
Estágios do Ciclo de Vida/fisiologia , Proteínas de Membrana , Miosinas , Plasmodium berghei , Plasmodium falciparum , Proteínas de Protozoários , Animais , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Miosinas/genética , Miosinas/metabolismo , Plasmodium berghei/genética , Plasmodium berghei/metabolismo , Plasmodium falciparum/genética , Plasmodium falciparum/metabolismo , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo
5.
Genome Announc ; 4(6)2016 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-27834708

RESUMO

We report the complete genome sequence of the first Mexican human coronavirus (HCoV) OC43, obtained by new-generation sequencing and a metagenomic approach, isolated from a child hospitalized with pneumonia. The genome is closely related to the other OC43 genome sequences available, ranging from 99.8% to 98.2% nucleotide sequence identity.

6.
Data Brief ; 6: 908-16, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26937470

RESUMO

Retinoblastoma (Rb) is a pediatric intraocular malignancy and probably the most robust clinical model on which genetic predisposition to develop cancer has been demonstrated. Since deletions in chromosome 13 have been described in this tumor, we performed next generation sequencing to test whether recurrent losses could be detected in low coverage data. We used Illumina platform for 13 tumor tissue samples: two pools of 4 retinoblastoma cases each and one pool of 5 medulloblastoma cases (raw data can be found at http://www.ebi.ac.uk/ena/data/view/PRJEB6630). We first created an in silico reference profile generated from a human sequenced genome (GRCh37p5). From this data we calculated an integrity score to get an overview of gains and losses in all chromosomes; we next analyzed each chromosome in windows of 40 kb length, calculating for each window the log2 ratio between reads from tumor pool and in silico reference. Finally we generated panoramic maps with all the windows whether lost or gained along each chromosome associated to its cytogenetic bands to facilitate interpretation. Expression microarrays was done for the same samples and a list of over and under expressed genes is presented here. For this detection a significance analysis was done and a log2 fold change was chosen as significant (raw data can be found at http://www.ncbi.nlm.nih.gov/geo/accession number GSE11488). The complete research article can be found at Cancer Genetics journal (Garcia-Chequer et al., in press) [1]. In summary here we provide an overview with visual graphics of gains and losses chromosome by chromosome in retinoblastoma and medulloblastoma, also the integrity score analysis and a list of genes with relevant expression associated. This material can be useful to researchers that may want to explore gains and losses in other malignant tumors with this approach or compare their data with retinoblastoma.

7.
Cancer Genet ; 209(3): 57-69, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26883451

RESUMO

Genes are frequently lost or gained in malignant tumors and the analysis of these changes can be informative about the underlying tumor biology. Retinoblastoma is a pediatric intraocular malignancy, and since deletions in chromosome 13 have been described in this tumor, we performed genome wide sequencing with the Illumina platform to test whether recurrent losses could be detected in low coverage data from DNA pools of Rb cases. An in silico reference profile for each pool was created from the human genome sequence GRCh37p5; a chromosome integrity score and a graphics 40 Kb window analysis approach, allowed us to identify with high resolution previously reported non random recurrent losses in all chromosomes of these tumors. We also found a pattern of gains and losses associated to clear and dark cytogenetic bands respectively. We further analyze a pool of medulloblastoma and found a more stable genomic profile and previously reported losses in this tumor. This approach facilitates identification of recurrent deletions from many patients that may be biological relevant for tumor development.


Assuntos
Deleção Cromossômica , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Neoplasias da Retina/genética , Retinoblastoma/genética , Feminino , Humanos , Masculino , Meduloblastoma/genética , Análise de Sequência com Séries de Oligonucleotídeos , Recidiva
8.
Amino Acids ; 48(1): 157-68, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26306845

RESUMO

The encapsulation of antitumor drugs in nanosized systems with pH-sensitive behavior is a promising approach that may enhance the success of chemotherapy in many cancers. The nanocarrier dependence on pH might trigger an efficient delivery of the encapsulated drug both in the acidic extracellular environment of tumors and, especially, in the intracellular compartments through disruption of endosomal membrane. In this context, here we reported the preparation of chitosan-based nanoparticles encapsulating methotrexate as a model drug (MTX-CS-NPs), which comprises the incorporation of an amino acid-based amphiphile with pH-responsive properties (77KS) on the ionotropic complexation process. The presence of 77KS clearly gives a pH-sensitive behavior to NPs, which allowed accelerated release of MTX with decreasing pH as well as pH-dependent membrane-lytic activity. This latter performance demonstrates the potential of these NPs to facilitate cytosolic delivery of endocytosed materials. Outstandingly, the cytotoxicity of MTX-loaded CS-NPs was higher than free drug to MCF-7 tumor cells and, to a lesser extent, to HeLa cells. Based on the overall results, MTX-CS-NPs modified with the pH-sensitive surfactant 77KS could be potentially useful as a carrier system for intracellular drug delivery and, thus, a promising targeting anticancer chemotherapeutic agent.


Assuntos
Aminoácidos/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Quitosana/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/instrumentação , Metotrexato/química , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos/métodos , Humanos , Concentração de Íons de Hidrogênio , Metotrexato/farmacologia , Nanopartículas/química
9.
J Biomed Mater Res A ; 103(1): 330-40, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24659574

RESUMO

Tissue engineering approaches for the development of a single epidermal-dermal scaffold to treat full-thickness skin defects have been limited by difficulties in the fabrication of a bilayer scaffold combining the specific properties of the epidermis and the dermis. Here we present an innovative approach to developing a scaffold that holds promise for skin tissue engineering. We utilize the spray-assisted layer-by-layer assembly technique to deposit a polyelectrolyte multilayer film composed of hyaluronic acid and poly-L-lysine (the epidermal component) on a porous hyaluronic acid scaffold (the dermal component), in a rapid and controlled manner. The multilayer film promotes cell adhesion, contributing to regeneration of the epidermal barrier functions of skin. While human keratinocytes attached and proliferated on the coated porous scaffolds, they did not invade the porous dermal component, thus leaving room for seeding of relevant fibroblast cell types in this scaffold. This scaffold therefore holds promise for co-culture of different cells, which may be useful for treatment of full-thickness skin defects as well as other tissue engineering applications.


Assuntos
Ácido Hialurônico , Pele , Engenharia Tecidual , Alicerces Teciduais , Células Cultivadas , Humanos , Microscopia de Força Atômica
10.
J Clin Microbiol ; 52(3): 803-13, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24353006

RESUMO

Recent evidence suggests that most influenza A virus gene segments can contribute to the pathogenicity of the virus. In this regard, the hemagglutinin (HA) subtype of the circulating strains has been closely surveyed, but the reassortment of internal gene segments is usually not monitored as a potential source of an increased pathogenicity. In this work, an oligonucleotide DNA microarray (PhyloFlu) designed to determine the phylogenetic origins of the eight segments of the influenza virus genome was constructed and validated. Clades were defined for each segment and also for the 16 HA and 9 neuraminidase (NA) subtypes. Viral genetic material was amplified by reverse transcription-PCR (RT-PCR) with primers specific to the conserved 5' and 3' ends of the influenza A virus genes, followed by PCR amplification with random primers and Cy3 labeling. The microarray unambiguously determined the clades for all eight influenza virus genes in 74% (28/38) of the samples. The microarray was validated with reference strains from different animal origins, as well as from human, swine, and avian viruses from field or clinical samples. In most cases, the phylogenetic clade of each segment defined its animal host of origin. The genomic fingerprint deduced by the combined information of the individual clades allowed for the determination of the time and place that strains with the same genomic pattern were previously reported. PhyloFlu is useful for characterizing and surveying the genetic diversity and variation of animal viruses circulating in different environmental niches and for obtaining a more detailed surveillance and follow up of reassortant events that can potentially modify virus pathogenicity.


Assuntos
Impressões Digitais de DNA/métodos , Genoma Viral , Técnicas de Genotipagem/métodos , Vírus da Influenza A/classificação , Influenza Humana/virologia , Análise em Microsséries/métodos , Infecções por Paramyxoviridae/veterinária , Animais , Análise por Conglomerados , Humanos , Vírus da Influenza A/genética , Vírus da Influenza A/isolamento & purificação , Infecções por Paramyxoviridae/virologia , Filogenia , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Virologia/métodos
11.
Biomaterials ; 34(38): 9763-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24074838

RESUMO

We report a photoactive surface coating which produces cytotoxic reactive oxygen species (ROS) upon irradiation with near infrared (NIR) light. The coating is assembled layer-by-layer, and consists of cross-linked hyaluronic acid (HA) and poly-l-lysine (PLL) modified with the photoactive molecule pheophorbide a. Pheophorbide a loading can be fine-tuned by varying the number of bilayers, yielding stable materials with the capacity to generate repeated and/or prolonged light-triggered ROS release. Light irradiation of the photoactive surface coatings provides a versatile platform for the spatiotemporal control of events at the material-tissue interface, such as bacterial colonization, platelet adhesion, and mammalian cell attachment.


Assuntos
Ácido Hialurônico/química , Luz , Polilisina/química , Escherichia coli/metabolismo , Humanos , Fotoquímica , Plasma Rico em Plaquetas/efeitos da radiação , Espécies Reativas de Oxigênio/química , Espécies Reativas de Oxigênio/metabolismo , Staphylococcus aureus/metabolismo
12.
J Pediatr (Rio J) ; 86(5): 400-4, 2010.
Artigo em Inglês, Português | MEDLINE | ID: mdl-20865211

RESUMO

OBJECTIVES: To examine the prevalence of under and overreporting of energy intake in adolescents and their associated factors. METHODS: Cross-sectional study with 96 postpubertal adolescents (47 normal-weight and 49 obese), mean age of 16.6±1.3 years. Weight and height were measured, and body mass index was calculated. Body composition was assessed by dual energy X-ray absorptiometry. Dietary intake was evaluated by a 3-day dietary record. Biochemical assessment was performed (serum total cholesterol, LDL-cholesterol, HDL-cholesterol, plasma glucose, and insulin). Underreporters reported energy intake < 1.35 x basal metabolic rate (BMR), whereas overreporters reported energy intake > 2.4 x BMR. RESULTS: Energy intake misreporting (under or overreporting) was identified in 65.6% of adolescents (64.6 and 1% of under and overreporting, respectively). Obese adolescents were 5.0 times more likely to underreport energy intake (95%CI 2.0-12.7) than normal-weight participants. Underreporters showed higher rates of insufficient intake of carbohydrate (19.3 vs. 12.1%, p = 0.046) and lipids (11.3 vs. 0%, p < 0.001) than plausible reporters. Cholesterol intake was also lower in underreporters (p = 0.017). There were no significant differences in body composition and biochemical parameters in relation to misreporting. CONCLUSIONS: The results obtained demonstrated a high percentage of misreporting of energy intake among adolescents, especially among obese subjects, which suggests that energy-adjusted nutrient intake values should be employed in diet-disease risk analysis in order to contribute to a reduction in errors associated with misreporting.


Assuntos
Metabolismo Basal , Ingestão de Energia , Estado Nutricional , Autorrevelação , Adolescente , Composição Corporal , Peso Corporal/fisiologia , Brasil , Distribuição de Qui-Quadrado , Estudos Transversais , Registros de Dieta , Inquéritos sobre Dietas , Comportamento Alimentar , Feminino , Humanos , Masculino , Obesidade/etiologia , Prevalência , Fatores de Risco , Estatísticas não Paramétricas
13.
J. pediatr. (Rio J.) ; 85(6): 503-508, nov.-dez. 2009. tab, ilus
Artigo em Português | LILACS | ID: lil-536180

RESUMO

OBJETIVO: Avaliar a densidade mineral óssea (DMO) e relacioná-la com a ingestão alimentar e composição corporal de adolescentes modelos de passarela. MÉTODOS: Estudo transversal avaliando 33 modelos e 33 não modelos de 15 a 18 anos pareadas por idade e índice de massa corporal (IMC). A densidade mineral óssea da coluna (L1-L4) foi avaliada por meio da técnica da absorciometria de feixe duplo de energia (Lunar® DPX Alpha), e a composição corporal, pela técnica de pletismografia. A ingestão alimentar foi avaliada por meio do registro alimentar de 3 dias. RESULTADOS: A média de idade das adolescentes foi de 16,75±1,04 anos, sendo que 24 por cento apresentaram IMC abaixo dos valores ideais para a idade. Não houve diferença de DMO entre modelos (1,108±0,080 g/cm2) e não modelos (1,096±0,102 g/cm2) (p > 0,05), sendo identificada uma porcentagem de 6 por cento de baixa DMO para a idade. Observou-se que a média de ingestão de energia foi menor entre as modelos em comparação às adolescentes não modelos (1.480,93±582,95 versus 1.973,00±557,63 kcal) (p > 0,05) e que a maioria das adolescentes de ambos os grupos apresentou consumo inadequado de micronutrientes, ressaltando-se a baixa ingestão de cálcio. Verificou-se correlação significativa da DMO apenas com a massa magra (kg) (modelos r = 0,362 e não modelos r = 0,618; p < 0,05). CONCLUSÃO: Apesar de não ter sido encontrada associação entre a DMO, o IMC e a ingestão de nutrientes importantes no processo de mineralização óssea, as inadequações na ingestão alimentar podem influenciar negativamente a aquisição de massa óssea, que se encontra potencializada neste estágio de vida.


OBJECTIVE: To evaluate the bone mineral density (BMD) and to relate it to the food intake and body composition of adolescent runway models. METHODS: Cross-sectional study evaluating 33 models and 33 non-models aged from 15 to 18 years, paired by age and body mass index (BMI). BMD of spine (L1-L4) was evaluated using the dual-energy X-ray absorptiometry technique (Lunar® DPX Alpha), and body composition was assessed by means of plethysmography. Food intake was evaluated by a 3-day-food record. RESULTS: The subjects mean age was 16.75±1.04 years, and 24 percent had BMI below ideal value for their age. BMD values (g/cm2) were similar between models (1.108±0.080) and non-models (1.096±0.102) (p > 0.05), and 6 percent of the participants had low BMD for age. We found that the mean energy intake was lower among models as compared to non-models (1,480.93±582.95 vs. 1,973.00±557.63 kcal) (p < 0.05) and that most of the adolescents in both groups presented an inadequate consumption of micronutrients, with emphasis to the low calcium intakes. There was only significant correlation between BMD and lean body mass (kg) (r = 0.362 for models and r = 0.618 for non-models) (p < 0.05). CONCLUSION: Although no association was found between BMD, BMI, and intake of nutrients which are important for the bone mineralization process, inadequacies of food intake have an adverse influence on the acquisition of bone mass, which is more effective at this stage of life.


Assuntos
Adolescente , Feminino , Humanos , Composição Corporal/fisiologia , Densidade Óssea/fisiologia , Ingestão de Alimentos/fisiologia , Ocupações/estatística & dados numéricos , Índice de Massa Corporal , Estudos Transversais
14.
J Pediatr (Rio J) ; 85(6): 503-8, 2009.
Artigo em Inglês, Português | MEDLINE | ID: mdl-19904480

RESUMO

OBJECTIVE: To evaluate the bone mineral density (BMD) and to relate it to the food intake and body composition of adolescent runway models. METHODS: Cross-sectional study evaluating 33 models and 33 non-models aged from 15 to 18 years, paired by age and body mass index (BMI). BMD of spine (L1-L4) was evaluated using the dual-energy X-ray absorptiometry technique (Lunar DPX Alpha), and body composition was assessed by means of plethysmography. Food intake was evaluated by a 3-day-food record. RESULTS: The subjects' mean age was 16.75+/-1.04 years, and 24% had BMI below ideal value for their age. BMD values (g/cm2) were similar between models (1.108+/-0.080) and non-models (1.096+/-0.102) (p > 0.05), and 6% of the participants had low BMD for age. We found that the mean energy intake was lower among models as compared to non-models (1,480.93+/-582.95 vs. 1,973.00+/-557.63 kcal) (p < 0.05) and that most of the adolescents in both groups presented an inadequate consumption of micronutrients, with emphasis to the low calcium intakes. There was only significant correlation between BMD and lean body mass (kg) (r = 0.362 for models and r = 0.618 for non-models) (p < 0.05). CONCLUSION: Although no association was found between BMD, BMI, and intake of nutrients which are important for the bone mineralization process, inadequacies of food intake have an adverse influence on the acquisition of bone mass, which is more effective at this stage of life.


Assuntos
Composição Corporal/fisiologia , Densidade Óssea/fisiologia , Ingestão de Alimentos/fisiologia , Ocupações/estatística & dados numéricos , Adolescente , Índice de Massa Corporal , Estudos Transversais , Feminino , Humanos
15.
Arq Bras Endocrinol Metabol ; 52(6): 1001-8, 2008 Aug.
Artigo em Português | MEDLINE | ID: mdl-18820811

RESUMO

OBJECTIVE: To verify the effects of weight loss on bone mass of obese adolescents submitted to a nutritional intervention based on a hypocaloric diet and nutritional advice over a nine-month-period. METHODS: Anthropometry, body composition, BMD and dietary intake were evaluated. RESULTS: Fifty-five adolescents, 78.2% females, within an average age of 16.6 (1.4) years old participated in the study. Sixteen participants who completed the study did not lose weight. The group that adhered to the nutritional intervention had a mean weight loss of 6.2 (4.6)% baseline. There was a significant increase in total BMD and bone mineral content (BMC) in those adolescents who did not lose weight, while increased BMC and bone area were verified in participants who lost weight, mainly when associated with body composition alterations while changing weight. CONCLUSION: The increment in bone mineral density, even throughout weight loss, has showed no negative effect on bone mass and has also emphasized the importance of nutritional improvement in total bone mass during adolescence.


Assuntos
Composição Corporal/fisiologia , Densidade Óssea/fisiologia , Dieta Redutora , Apoio Nutricional , Obesidade/dietoterapia , Redução de Peso/fisiologia , Adolescente , Antropometria , Osso e Ossos/patologia , Métodos Epidemiológicos , Feminino , Humanos , Masculino
16.
Arq. bras. endocrinol. metab ; 52(6): 1001-1008, ago. 2008. graf, tab
Artigo em Português | LILACS | ID: lil-492931

RESUMO

OBJETIVO: Verificar os efeitos da perda de peso na densidade mineral óssea (DMO) de adolescentes obesos submetidos a intervenção com base em dieta hipocalórica e orientações durante nove meses. MÉTODOS: Realizaram-se avaliações da antropometria, da composição corporal, da DMO e do consumo alimentar. RESULTADOS: Participaram do estudo 55 adolescentes, 78,2 por cento meninas, com média de 16,6 (1,4) anos. Destes, 44,4 por cento não apresentaram redução do peso. O grupo que respondeu à intervenção apresentou média de perda de peso de 6,2 por cento (4,6) do peso inicial. Houve aumento significativo da DMO e conteúdo mineral ósseo (CMO) entre os adolescentes não-respondedores e aumento do CMO e área óssea entre os respondedores, associados, principalmente, com as alterações da composição corporal com o ganho ou a perda de peso. CONCLUSÃO: O aumento da massa óssea mesmo com a perda de peso demonstrou que o emagrecimento não ter efeito negativo do emagrecimento e denota provável contribuição da melhora dos hábitos alimentares na aquisição óssea de adolescentes.


OBJECTIVE: To verify the effects of weight loss on bone mass of obese adolescents submitted to a nutritional intervention based on a hypocaloric diet and nutritional advice over a nine-month-period. METHODS: Anthropometry, body composition, BMD and dietary intake were evaluated. RESULTS: Fifty-five adolescents, 78.2 percent females, within an average age of 16.6 (1.4) years old participated in the study. Sixteen participants who completed the study did not lose weight. The group that adhered to the nutritional intervention had a mean weight loss of 6.2 (4.6) percent baseline. There was a significant increase in total BMD and bone mineral content (BMC) in those adolescents who did not lose weight, while increased BMC and bone area were verified in participants who lost weight, mainly when associated with body composition alterations while changing weight. CONCLUSION: The increment in bone mineral density, even throughout weight loss, has showed no negative effect on bone mass and has also emphasized the importance of nutritional improvement in total bone mass during adolescence.


Assuntos
Adolescente , Feminino , Humanos , Masculino , Composição Corporal/fisiologia , Densidade Óssea/fisiologia , Dieta Redutora , Apoio Nutricional , Obesidade/dietoterapia , Redução de Peso/fisiologia , Antropometria , Osso e Ossos/patologia , Métodos Epidemiológicos
17.
J Pediatr (Rio J) ; 84(3): 258-63, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18535732

RESUMO

OBJECTIVE: To investigate whether levels of autoantibodies to oxidized LDL (anti-oxLDL) in the plasma of adolescents correlates with their anthropometric measurements and lipid profiles. METHODS: The study enrolled 150 adolescents aged between 10 and 15 years, recruited from the obesity clinic at Universidade Federal de São Paulo (SP) and from public schools in Piracicaba, SP, Brazil. Anthropometric measurements such as body mass index and waist and arm circumferences were used to classify the adolescents as having healthy weight, overweight or obesity. Colorimetric enzymatic methods were used for biochemical lipid profile analysis and ELISA was used to determine anti-oxLDL autoantibody levels. RESULTS: Analysis of anthropometric variables indicated that the obese group's profile was abnormal compared to the healthy weight and overweight groups (p < 0.01), indicating cardiovascular risk. Analysis of the lipid profiles demonstrated statistically significant differences in concentrations of total cholesterol (p = 0.011), HDL-cholesterol (p = 0.001) and LDL-cholesterol (p < 0.042) between the healthy weight group and the obese group. Analysis of plasma anti-oxLDL autoantibodies demonstrated that the overweight (p = 0.012) and obese groups (p < 0.001) had higher values than the healthy weight group. There were also correlations between anti-oxLDL autoantibody levels and anthropometric variables. CONCLUSIONS: In adolescents the presence of anti-oxLDL autoantibodies and metabolic changes to the lipid profile vary in proportion with anthropometric parameters, which makes anti-oxLDL concentration a potential biochemical indicator of risk of metabolic syndrome.


Assuntos
Autoanticorpos/sangue , Lipídeos/sangue , Lipoproteínas LDL/imunologia , Estado Nutricional , Obesidade/sangue , Adolescente , Biomarcadores/sangue , Constituição Corporal , Estudos de Coortes , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Lipoproteínas LDL/sangue , Masculino , Síndrome Metabólica/etiologia , Obesidade/imunologia , Fatores de Risco
18.
J. pediatr. (Rio J.) ; 84(3): 258-263, May-June. 2008. graf, tab
Artigo em Inglês, Português | LILACS | ID: lil-485284

RESUMO

OBJETIVO: Avaliar se o conteúdo de auto-anticorpos anti-LDL oxidada (anti-LDLox) no plasma de adolescentes correlaciona-se com suas medidas antropométricas e com o perfil lipídico. MÉTODOS: O estudo incluiu 150 adolescentes com idade entre 10 e 15 anos, recrutados do ambulatório de obesidade da Universidade Federal de São Paulo (SP) e de escolas públicas de Piracicaba (SP). Foram avaliadas medidas antropométricas, como índice de massa corporal, circunferência de cintura e do braço, classificando os adolescentes em eutrófico, sobrepeso e obeso. Para as análises bioquímicas, foi realizado o perfil lipídico através de métodos enzimáticos colorimétricos, e para detecção do conteúdo de auto-anticorpos anti-LDLox, utilizou-se o método de ELISA. RESULTADOS: Segundo análises das variáveis antropométricas, o grupo obeso apresentou perfil alterado em relação aos grupos eutrófico e sobrepeso (p < 0,01), indicando risco cardiovascular. Quando o perfil lipídico foi avaliado, observaram-se diferenças estatisticamente significativas para as concentrações de colesterol total (p = 0,011), HDL-colesterol (p = 0,001) e LDL-colesterol (p < 0,042) nos grupos eutrófico e obeso. Para as análises de auto-anticorpos anti-LDLox plasmática, os grupos sobrepeso (p = 0,012) e obeso (p < 0,001) apresentaram valores superiores ao grupo eutrófico. Também houve correlações entre os auto-anticorpos anti-LDLox e variáveis antropométricas. CONCLUSÃO: A presença de auto-anticorpos anti-LDLox em adolescentes e as alterações metabólicas no perfil lipídico variaram de modo proporcional com parâmetros antropométricos, o que torna o conteúdo de anti-LDLox um potencial indicador bioquímico de risco para síndrome metabólica.


OBJECTIVE: To investigate whether levels of autoantibodies to oxidized LDL (anti-oxLDL) in the plasma of adolescents correlates with their anthropometric measurements and lipid profiles. METHODS: The study enrolled 150 adolescents aged between 10 and 15 years, recruited from the obesity clinic at Universidade Federal de São Paulo (SP) and from public schools in Piracicaba, SP, Brazil. Anthropometric measurements such as body mass index and waist and arm circumferences were used to classify the adolescents as having healthy weight, overweight or obesity. Colorimetric enzymatic methods were used for biochemical lipid profile analysis and ELISA was used to determine anti-oxLDL autoantibody levels. RESULTS: Analysis of anthropometric variables indicated that the obese group's profile was abnormal compared to the healthy weight and overweight groups (p < 0.01), indicating cardiovascular risk. Analysis of the lipid profiles demonstrated statistically significant differences in concentrations of total cholesterol (p = 0.011), HDL-cholesterol (p = 0.001) and LDL-cholesterol (p < 0.042) between the healthy weight group and the obese group. Analysis of plasma anti-oxLDL autoantibodies demonstrated that the overweight (p = 0.012) and obese groups (p < 0.001) had higher values than the healthy weight group. There were also correlations between anti-oxLDL autoantibody levels and anthropometric variables. CONCLUSIONS: In adolescents the presence of anti-oxLDL autoantibodies and metabolic changes to the lipid profile vary in proportion with anthropometric parameters, which makes anti-oxLDL concentration a potential biochemical indicator of risk of metabolic syndrome.


Assuntos
Adolescente , Feminino , Humanos , Masculino , Autoanticorpos/sangue , Lipídeos/sangue , Lipoproteínas LDL/imunologia , Estado Nutricional , Obesidade/sangue , Constituição Corporal , Biomarcadores/sangue , Estudos de Coortes , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Lipoproteínas LDL/sangue , Síndrome Metabólica/etiologia , Obesidade/imunologia , Fatores de Risco
19.
Eur J Gastroenterol Hepatol ; 18(12): 1241-5, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17099371

RESUMO

BACKGROUND: Despite the increasing prevalence of nonalcoholic fatty liver disease, its pathogenesis and clinical significance remain poorly defined and there is no ideal treatment. OBJECTIVE: The aim of this study was to assess the short-term (12-week) multidisciplinary therapy on visceral adiposity and nonalcoholic fatty liver disease control. METHODS: We evaluated and compared the distribution of visceral adiposity and nonalcoholic fatty liver disease, by ultrasonography, in 73 post-puberty obese participants (17.01+/-1.6 years old; body mass index 36.54+/-2.86 kg/m), submitted to a multidisciplinary treatment without medications, at the beginning and after 12 weeks of intervention. Descriptive and one-way analysis of variance, and paired t-test were performed. RESULTS: The results indicated that after intervention the adolescents had a significant reduction in visceral adiposity (4.05+/-1.55 to 3.37+/-1.44) and nonalcoholic fatty liver disease prevalence (from 52 to 29% on the right side and from 48 to 29% on the left side). It is a positive result because nonalcoholic fatty liver disease can progress to cirrhosis, even in children and adolescents. CONCLUSIONS: The short-term treatment suggests a profound impact on the control of obesity-related co-morbidities in young people.


Assuntos
Fígado Gorduroso/etiologia , Obesidade/complicações , Obesidade/terapia , Adiposidade , Adolescente , Adulto , Antropometria , Glicemia/metabolismo , Índice de Massa Corporal , Terapia Combinada , Dieta Redutora , Ingestão de Alimentos , Exercício Físico , Fígado Gorduroso/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Insulina/sangue , Estilo de Vida , Lipídeos/sangue , Masculino , Obesidade/diagnóstico por imagem , Obesidade/fisiopatologia , Índice de Gravidade de Doença , Resultado do Tratamento , Ultrassonografia
20.
Rev. bras. med. esporte ; 12(5): 263-267, set.-out. 2006. tab
Artigo em Português | LILACS | ID: lil-453759

RESUMO

O objetivo do presente estudo foi avaliar as alterações promovidas, por intervenção multidisciplinar, nas concentrações plasmáticas de grelina e leptina, adiposidade visceral e prevalência de esteatose hepática não alcoólica (NAFLD), em adolescentes obesos. Foram avaliados 28 adolescentes obesos, 16 meninas (IMC 34,58 ± 3,86kg/m²) e 12 meninos (IMC 37,08 ± 3,17kg/m²), com idade entre 15 e 19 anos, quanto à concentração de leptina, grelina, insulina, assim como a adiposidade visceral e o diagnóstico de NAFLD pelo método de ultra-sonografia. Os resultados demonstraram redução significante na concentração circulante de grelina e leptina e na adiposidade visceral (p < 0,01). Houve ainda redução percentual na prevalência de NAFLD, sendo este um resultado relevante, visto que esta doença pode progredir para cirrose, tanto em crianças quanto em adolescentes obesos. Este tipo de tratamento demonstrou ser eficiente na melhora do perfil metabólico e hormonal, contribuindo para o controle da obesidade e suas co-morbidades em adolescentes obesos.


The aim of this study was to assess the changes promoted by a multidisciplinary therapy in ghrelin and leptin concentrations, visceral adiposity and non-alcoholic fat liver disease-NAFLD, in obese adolescents. A total of 28 obese adolescents, 16 girls (BMI 34.58 ± 3,86 wt/ht²) and 12 boys (BMI 37.08 ± 3.17 wt/ht²), aged between 15 and 19 years old, was evaluated to leptin, ghrelin and insulin concentrations, visceral adiposity and NAFLD through ultrasonography. The results showed a significant decrease in ghrelin, leptin concentrations and visceral adiposity (p < 0.01). Moreover, a decrease in the NAFLD prevalence was observed. It is an important result, since this disease can progress to cirrhosis, not only in children but also in obese adolescents. This kind of treatment can be efficient to improve metabolic and hormonal profile, as well as, to control obesity and related co-morbidities in obese adolescents.


El objetivo del presente trabajo ha sido evaluar las alteraciones promovidas por la intervención multidisciplinar, en las concentra- ciones plasmáticas de grelina y leptina, adiposidad visceral y prevalencia de esteatosis hepática no alcohólica - NAFLD, en adolescentes obesos. 28 adolescentes obesos, 16 chicas (IMC 34,58 ± 3,86 kg/m²) y 12 chicos (IMC 37,08 ± 3,17 kg/m²), con edades entre 15 y 19 años, fueron evaluados respecto a la concentración de leptina, grelina, insulina, así como a la adiposidad visceral y el diagnóstico de NAFLD por el método de ultrasonografía. Los resultados demostraron una reducción significante en la concentra- ción circulante de grelina y leptina y en la adiposidad visceral (p < 0,01). Hubo aún una reducción porcentual en la prevalencia de NAFLD, siendo este un resultado relevante, ya que esta enfermedad puede progresar hasta la cirrosis, tanto en niños como en adolescentes obesos. Este tipo de tratamiento demostró ser eficiente en la mejora del perfil metabólico y hormonal, contribuyendo para el control de la obesidad y su comorbilidad en adolescentes obesos.

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