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Propolis consists of a honeybee product, with a complex mix of substances that have been widely used in traditional medicine. Among several compounds present in propolis, caffeic acid phenethyl ester (CAPE), and pinocembrin emerge as two principal bioactive compounds, with benefits in a variety of body systems. In addition to its well-explored pharmacological properties, neuropharmacological activities have been poorly discussed. In an unprecedented way, the present review addresses the current finding on the promising therapeutic purposes of propolis, focusing on CAPE and pinocembrin, highlighting its use on neurological disturbance, as cerebral ischemia, neuroinflammation, convulsion, and cognitive impairment, as well as psychiatric disorders, such as anxiety and depression. In addition, we provide a critical analysis, discussion, and systematization of the molecular mechanisms which underlie these central nervous system effects. We hypothesize that the pleiotropic action of CAPE and pinocembrin, per se or associated with other substances present in propolis may result in the therapeutic activities reported. Inhibition of the pro-inflammatory cascade, antioxidant activity, and positive neurotrophic modulatory effects consist of the main molecular targets attributed to CAPE and pinocembrin in health benefits.
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Doenças do Sistema Nervoso , Própole , Animais , Abelhas , Ácidos Cafeicos/farmacologia , Flavanonas , Humanos , Doenças do Sistema Nervoso/tratamento farmacológico , Álcool Feniletílico/análogos & derivadosRESUMO
Diagnosis of pulmonary tuberculosis is usually achieved by testing sputum for presence of Mycobacterium tuberculosis by microscopy, culture or nucleic acid amplification tests. However, many individuals are unable to produce sputum, particularly early in the course of illness. Studies have reported that oral swabs, assayed by nucleic acid amplification tests, may be a suitable substitute or complement to sputum testing. To determine whether this method could be useful of case finding, in which bacillary load is often lower, we evaluated it in the setting of a mass tuberculosis screening study in prison inmates in Brazil. For this sub-study, we enrolled 128 individuals with pulmonary tuberculosis confirmed by sputum Xpert testing, and 128 controls who tested negative by sputum culture and Xpert. We collected two oral swabs by participant, prior to starting treatment. Swabs were collected from the tongue by brushing along the surface for 10 times. The sensitivity of a single oral swab was 43% (N = 55/128; 95% CI: 34-52%). Using two consecutive oral swabs the sensitivity increased to 51% (N = 66/128; 95% CI: 43-60%). The specificity was 100% (128/128). In participants with high mycobaterial load in the sputum, the combined sensitivity was 90% (N = 9/10). In the participants with medium mycobaterial load in the sputum, the combined sensitivity was 79% (N = 23/29). In the participants with low or very low mycobaterial load in the sputum, the combined sensitivity was 38% (N = 34/89). Our data suggest that oral swab sampling, assayed by Xpert, has comparable sensitivity to sputum in participants with high and medium mycobacterial load in the sputum. However, 70% (89/128) of individuals identified through our mass screening study (Carbone et al.) had detection number low or very low in their sputum. In this population, oral swab testing may not have sufficient sensitivity as currently performed. Further studies are needed to identify alternative non-sputum sampling strategies in this population.
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BACKGROUND: Paspalum notatum exhibits both sexual and apomictic cytotypes and, thus, is considered a good model for studies of apomixis because it facilitates comparative approaches. In this work, transcriptome sequencing was used to compare contrasting P. notatum cytotypes to identify differential expression patterns and candidate genes involved in the regulation of expression of this trait. RESULTS: We built a comprehensive transcriptome using leaf and inflorescence from apomictic tetraploids and sexual diploids/tetraploids and a coexpression network based on pairwise correlations between transcript expression profiles. We identified genes exclusively expressed in each cytotype and genes differentially expressed between pairs of cytotypes. Gene Ontology enrichment analyses were performed to better interpret the data. We de novo assembled 114,306 reference transcripts. In total, 536 candidate genes possibly associated with apomixis were detected through statistical analyses of the differential expression data, and several interacting genes potentially linked to the apomixis-controlling region, genes that have already been reported in the literature, and their neighbors were transcriptionally related in the coexpression network. CONCLUSIONS: Apomixis is a highly desirable trait in modern agriculture due to the maintenance of the characteristics of the mother plant in the progeny. The reference transcriptome, candidate genes and their coexpression network identified in this work represent rich resources for future grass breeding programs.
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Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Paspalum/genética , Folhas de Planta/genética , Transcriptoma , Biologia Computacional/métodos , DNA de Plantas , Sequenciamento de Nucleotídeos em Larga Escala , Anotação de Sequência Molecular , Proteínas de Plantas/genética , Reprodutibilidade dos TestesRESUMO
The goal of this research was to generate networks of co-expressed genes to explore the genomic responses of Rhizophora mangle L. populations to contrasting environments and to use gene network analysis to investigate their capacity for adaptation in the face of historical and future perturbations and climatic changes. RNA sequencing data were generated for R. mangle samples collected under field conditions from contrasting climate zones in the equatorial and subtropical regions of Brazil. A gene co-expression network was constructed using Pearson's correlation coefficient, showing correlations among 78,364 transcriptionally coordinated genes. Each region exhibited two distinct network profiles; genes correlated with the oxidative stress response showed higher relative expression levels in subtropical samples than in equatorial samples, whereas genes correlated with the hyperosmotic salinity response, heat response and UV response had higher expression levels in the equatorial samples than in the subtropical samples. In total, 992 clusters had enriched ontology terms, which suggests that R. mangle is under higher stress in the equatorial region than in the subtropical region. Increased heat may thus pose a substantial risk to species diversity at the center of its distribution range in the Americas. This study, which was performed using trees in natural field conditions, allowed us to associate the specific responses of genes previously described in controlled environments with their responses to the local habitat where the species occurs. The study reveals the effects of contrasting environments on gene expression in R. mangle, shedding light on the different abiotic variables that may contribute to the genetic divergence previously described for the species through the use of simple sequence repeats (SSRs). These effects may result from two fundamental processes in evolution, namely, phenotypic plasticity and natural selection.
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Rubber tree (Hevea brasiliensis) cultivation is the main source of natural rubber worldwide and has been extended to areas with suboptimal climates and lengthy drought periods; this transition affects growth and latex production. High-density genetic maps with reliable markers support precise mapping of quantitative trait loci (QTL), which can help reveal the complex genome of the species, provide tools to enhance molecular breeding, and shorten the breeding cycle. In this study, QTL mapping of the stem diameter, tree height, and number of whorls was performed for a full-sibling population derived from a GT1 and RRIM701 cross. A total of 225 simple sequence repeats (SSRs) and 186 single-nucleotide polymorphism (SNP) markers were used to construct a base map with 18 linkage groups and to anchor 671 SNPs from genotyping by sequencing (GBS) to produce a very dense linkage map with small intervals between loci. The final map was composed of 1,079 markers, spanned 3,779.7 cM with an average marker density of 3.5 cM, and showed collinearity between markers from previous studies. Significant variation in phenotypic characteristics was found over a 59-month evaluation period with a total of 38 QTLs being identified through a composite interval mapping method. Linkage group 4 showed the greatest number of QTLs (7), with phenotypic explained values varying from 7.67 to 14.07%. Additionally, we estimated segregation patterns, dominance, and additive effects for each QTL. A total of 53 significant effects for stem diameter were observed, and these effects were mostly related to additivity in the GT1 clone. Associating accurate genome assemblies and genetic maps represents a promising strategy for identifying the genetic basis of phenotypic traits in rubber trees. Then, further research can benefit from the QTLs identified herein, providing a better understanding of the key determinant genes associated with growth of Hevea brasiliensis under limiting water conditions.
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Among rubber tree species, which belong to the Hevea genus of the Euphorbiaceae family, Hevea brasiliensis (Willd. ex Adr.de Juss.) Muell. Arg. is the main commercial source of natural rubber production worldwide. Knowledge of the population structure and linkage disequilibrium (LD) of this species is essential for the efficient organization and exploitation of genetic resources. Here, we obtained single-nucleotide polymorphisms (SNPs) using a genotyping-by-sequencing (GBS) approach and then employed the SNPs for the following objectives: (i) to identify the positions of SNPs on a genetic map of a segregating mapping population, (ii) to evaluate the population structure of a germplasm collection, and (iii) to detect patterns of LD decay among chromosomes for future genetic association studies in rubber tree. A total of 626 genotypes, including both germplasm accessions (368) and individuals from a genetic mapping population (254), were genotyped. A total of 77,660 and 21,283 SNPs were detected by GBS in the germplasm and mapping populations, respectively. The mapping population, which was previously mapped, was constructed with 1,062 markers, among which only 576 SNPs came from GBS, reducing the average interval between two adjacent markers to 4.4 cM. SNPs from GBS genotyping were used for the analysis of genetic structure and LD estimation in the germplasm accessions. Two groups, which largely corresponded to the cultivated and wild populations, were detected using STRUCTURE and via principal coordinate analysis. LD analysis, also using the mapped SNPs, revealed that non-random associations varied along chromosomes, with regions of high LD interspersed with regions of low LD. Considering the length of the genetic map (4,693 cM) and the mean LD (0.49 for cultivated and 0.02 for wild populations), a large number of evenly spaced SNPs would be needed to perform genome-wide association studies in rubber tree, and the wilder the genotypes used, the more difficult the mapping saturation.
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Hevea brasiliensis is a native species of the Amazon Basin of South America and the primary source of natural rubber worldwide. Due to the occurrence of South American Leaf Blight disease in this area, rubber plantations have been extended to suboptimal regions. Rubber tree breeding is time-consuming and expensive, but molecular markers can serve as a tool for early evaluation, thus reducing time and costs. In this work, we constructed six different cDNA libraries with the aim of developing gene-targeted molecular markers for the rubber tree. A total of 8,263 reads were assembled, generating 5,025 unigenes that were analyzed; 912 expressed sequence tags (ESTs) represented new transcripts, and two sequences were highly up-regulated by cold stress. These unigenes were scanned for microsatellite (SSR) regions and single nucleotide polymorphisms (SNPs). In total, 169 novel EST-SSR markers were developed; 138 loci were polymorphic in the rubber tree, and 98 % presented transferability to six other Hevea species. Locus duplication was observed in H. brasiliensis and other species. Additionally, 43 SNP markers in 13 sequences that showed similarity to proteins involved in stress response, latex biosynthesis and developmental processes were characterized. cDNA libraries are a rich source of SSR and SNP markers and enable the identification of new transcripts. The new markers developed here will be a valuable resource for linkage mapping, QTL identification and other studies in the rubber tree and can also be used to evaluate the genetic variability of other Hevea species, which are valuable assets in rubber tree breeding.
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BACKGROUND: Obesity in infancy and adolescence has acquired epidemic dimensions worldwide and is considered a risk factor for a number of disorders that can manifest at an early age, such as Metabolic Syndrome (MS). In this study, we evaluated overweight, obese, and extremely obese adolescents for the presence of MS, and studied the prevalence of single factors of the syndrome in this population. METHODS: A total of 321 adolescents (174 females and 147 males) aged 10 to 16 years, attending the Adolescent Outpatient Clinic of Botucatu School of Medicine, Brazil, between April 2009 and April 2011 were enrolled in this study. Adolescents underwent anthropometric evaluation (weight, height, and abdominal circumference) and Body Mass Index (BMI) was estimated according to age and gender, following Disease Control and Prevention Centers recommendations (CDC, 2000). Blood pressure was measured and individuals with BMI ≥ 85th percentile were submitted to laboratory evaluation for Total Cholesterol, HDL and LDL Cholesterol, Triglycerides, Fasting Insulinemia, and Fasting Glycemia to identify MS factors, according to the criteria suggested by the International Diabetes Federation. Insulin resistance was calculated by HOMA-IR, Quicki, and Fasting Glycemia/Fasting Insulinemia (FGI). RESULTS AND DISCUSSION: Of the 321 adolescents, 95 (29.6%) were overweight, 129 (40.2%) were obese, and 97 (30.2%) were extremely obese. Around 18% were diagnosed with MS. The most prevalent risk factors were abdominal circumference ≥90th percentile (55%), HDL < 40 mg/dL (35.5%), High Pressure ≥130/85 mm/Hg (21%), Triglycerides ≥150 mg/dL (18.5%), and Fasting Glycemia ≥100 mg/dL (2%). Insulin resistance was observed in 65% of the adolescents. CONCLUSION: An increased prevalence of overweight and obesity, together with cardiometabolic risk factors such as dyslipidemia and abnormal blood pressure, were observed in adolescents, contributing to the onset of metabolic syndrome at younger ages. Risk factors for MS were more prevalent in females.
Assuntos
Síndrome Metabólica/epidemiologia , Obesidade/epidemiologia , Sobrepeso/epidemiologia , Adolescente , Glicemia/análise , Pressão Sanguínea , Composição Corporal , Índice de Massa Corporal , Peso Corporal , Brasil/epidemiologia , Criança , Colesterol/sangue , Jejum , Feminino , Humanos , Resistência à Insulina , Masculino , Síndrome Metabólica/etiologia , Avaliação Nutricional , Obesidade/complicações , Sobrepeso/complicações , Prevalência , Fatores de Risco , Triglicerídeos/sangueRESUMO
OBJECTIVE: To evaluate the behavior of biomarkers of bone formation and resorption in healthy male Brazilian adolescents according to their biological maturation. METHODS: Eighty-seven volunteers were divided into age groups according to bone age (BA): 10-12 years (n = 25), 13-15 years (n = 36), and 16-18 years (n = 26). Weight (kg), height (m), body mass index (kg/m(2)), calcium intake from 3 days assessed by 24-h food recall (mg/day), pubertal event evaluation by Tanner criteria, and serum biomarker levels (osteocalcin [OC] [ng/mL], bone alkaline phosphatase [BAP] [U/L], and serum carboxyterminal telopeptide [S-CTx] [ng/mL]) were recorded and correlated to bone mineral density (BMD) (g/cm(2)) measured by dual energy X-ray absorptiometry of the lumbar spine, proximal femur, and whole body. RESULTS: Biomarkers showed similar behaviors, presenting higher median values in the 13-15 year group (BAP = 154.71 U/L, OC = 43.0 ng/mL, S-CTx = 2.09 ng/mL; p < 0.01) and when adolescents were in the pubertal stage G4. Median biomarker values decreased with advancing BA and sexual maturation. Biomarker values showed parallelism with peak height velocity, and, interestingly, bone formation biomarkers indicated significant negative correlation with BMD in the different evaluated locations, i.e., higher BMD values correlated with lower bone biomarker values. CONCLUSIONS: This is the first study of healthy Brazilian adolescents with rigid and careful inclusion and exclusion criteria to assess the correlation of bone markers and BMD with biological maturation indicators. Our results can help understand bone turnover and monitor bone metabolism.
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Fosfatase Alcalina/sangue , Densidade Óssea/fisiologia , Osso e Ossos/metabolismo , Colágeno Tipo I/sangue , Osteocalcina/sangue , Peptídeos/sangue , Maturidade Sexual/fisiologia , Adolescente , Biomarcadores/sangue , Índice de Massa Corporal , Reabsorção Óssea/sangue , Brasil , Estudos Transversais , Humanos , Masculino , Osteogênese/fisiologia , Estatísticas não ParamétricasRESUMO
OBJETIVO: Avaliar o comportamento de biomarcadores de formação e reabsorção óssea em adolescentes brasileiros em função da sua maturação biológica. MÉTODOS: Oitenta e sete voluntários foram divididos em grupos segundo a idade óssea (IO): 10-12 anos (n = 25), 13-15 anos (n = 36) e 16-18 anos (n = 26). Foram analisados peso (kg), estatura (m), índice de massa corporal (kg/m2), ingestão de cálcio de 3 dias (mg/dia), avaliação dos eventos pubertários pelos critérios de Tanner, níveis dos biomarcadores [osteocalcina (OC) (ng/mL), fosfatase alcalina óssea (FAO) (U/L), telopeptídeo carboxiterminal sérico (S-CTx) (ng/mL)] e sua correlação com a densidade mineral óssea (DMO) (g/cm2) por atenuação de raios X de dupla energia da coluna lombar, do fêmur proximal e de corpo total. RESULTADOS: Os biomarcadores mostraram comportamento semelhante, apresentando medianas elevadas dos 13 aos 15 anos (FAO = 154,71 U/L, OC = 43,0 ng/mL, S-CTx = 2,09 ng/mL; p < 0,01) e no estágio puberal G4. As medianas decresceram com o avançar da IO e da maturação sexual. Os níveis dos biomarcadores mostraram paralelismo com pico de velocidade em estatura, e, curiosamente, os biomarcadores de formação indicaram correlação negativa com a DMO, isto é, valores de DMO elevados se correlacionaram com valores baixos dos biomarcadores. CONCLUSÕES: Este é o primeiro estudo em adolescentes brasileiros com critérios de inclusão e exclusão rígidos e cuidadosos a avaliar a correlação entre marcadores ósseos e DMO frente a indicadores da maturação biológica. Os resultados ajudam a compreender o turnover ósseo e o monitoramento do metabolismo ósseo.
OBJECTIVE: To evaluate the behavior of biomarkers of bone formation and resorption in healthy male Brazilian adolescents according to their biological maturation. METHODS: Eighty-seven volunteers were divided into age groups according to bone age (BA): 10-12 years (n = 25), 13-15 years (n = 36), and 16-18 years (n = 26). Weight (kg), height (m), body mass index (kg/m2), calcium intake from 3 days assessed by 24-h food recall (mg/day), pubertal event evaluation by Tanner criteria, and serum biomarker levels (osteocalcin [OC] [ng/mL], bone alkaline phosphatase [BAP] [U/L], and serum carboxyterminal telopeptide [S-CTx] [ng/mL]) were recorded and correlated to bone mineral density (BMD) (g/cm2) measured by dual energy X-ray absorptiometry of the lumbar spine, proximal femur, and whole body. RESULTS: Biomarkers showed similar behaviors, presenting higher median values in the 13-15 year group (BAP = 154.71 U/L, OC = 43.0 ng/mL, S-CTx = 2.09 ng/mL; p < 0.01) and when adolescents were in the pubertal stage G4. Median biomarker values decreased with advancing BA and sexual maturation. Biomarker values showed parallelism with peak height velocity, and, interestingly, bone formation biomarkers indicated significant negative correlation with BMD in the different evaluated locations, i.e., higher BMD values correlated with lower bone biomarker values. CONCLUSIONS: This is the first study of healthy Brazilian adolescents with rigid and careful inclusion and exclusion criteria to assess the correlation of bone markers and BMD with biological maturation indicators. Our results can help understand bone turnover and monitor bone metabolism.
Assuntos
Adolescente , Humanos , Masculino , Fosfatase Alcalina/sangue , Densidade Óssea/fisiologia , Osso e Ossos/metabolismo , Colágeno Tipo I/sangue , Osteocalcina/sangue , Peptídeos/sangue , Maturidade Sexual/fisiologia , Índice de Massa Corporal , Brasil , Biomarcadores/sangue , Reabsorção Óssea/sangue , Estudos Transversais , Osteogênese/fisiologia , Estatísticas não ParamétricasRESUMO
Bone turnover is affected by exercise throughout the lifespan, especially during childhood and adolescence. The objective of this study was to investigate the impact of different sports on total and regional bone mineral density in male Brazilian adolescent athletes. Forty-six adolescents aged 10-18 years participated in the study: 12 swimmers, 10 tennis players, 10 soccer players, and 14 sedentary individuals. The athletes had engaged in physical activities for more than 10 h per week in the previous 6 months. Bone mineral density of the lumbar spine (L1-L4), left proximal femur region, and whole body was evaluated by dual-energy X-ray absorptiometry. Results showed higher mean values in the proximal femur region of tennis and soccer players (1.02 ± 0.18; 0.96 ± 0.16, respectively) than swimmers and controls (0.91 ± 0.14 and 0.87 ± 0.06, respectively) (P < 0.05). In relation to the impact of sporting activities based on bone age determination, we observed significant differences in bone mineral density at all evaluated sites at the end of puberty (16-18 years) compared with 10-12 years, with increases of 78% in the lumbar spine, 47% in the proximal femur, and 38% in the whole body.
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Atletas , Densidade Óssea , Exercício Físico/fisiologia , Futebol/fisiologia , Natação/fisiologia , Tênis/fisiologia , Absorciometria de Fóton , Adolescente , Brasil , Criança , Fêmur/diagnóstico por imagem , Fêmur/fisiologia , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/fisiologia , Masculino , Puberdade , Comportamento SedentárioRESUMO
Mating-type genes control the entry into the sexual cycle, mating identity and sexual development in fungi. The mat A-2 and mat A-3 genes, present in the mat A idiomorph of the filamentous fungus Neurospora crassa, are required for post-fertilization functions but are not essential for mating identity. Their putative roles as transcription factors are based on the similarity of mat A-2 with the Podospora anserina SMR1 gene and an HMG motif present in the mat A-3 gene. In this work the yeast two-hybrid system was used to identify transcriptional activity and protein-protein interaction of N. crassamat A-2 and mat A-3 genes. We observed that the mat A-3 protein alone is capable of weakly activating transcription of yeast reporter genes; it also binds with low specificity to the GAL1 promoter sequence, possibly due to its HMG domain. Our results also indicate that mat A-3 is capable to form homodimers, and interact with mat A-2. Interference on yeast growth was observed on some transformants suggesting a toxic action of the mat A-2 protein. Our data on pattern of interactions of mat proteins contributes towards understanding the control of vegetative and sexual cycles in filamentous fungi.
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Mating-type genes control the entry into the sexual cycle, mating identity and sexual development in fungi. The mat A-2 and mat A-3 genes, present in the mat A idiomorph of the filamentous fungus Neurospora crassa, are required for post-fertilization functions but are not essential for mating identity. Their putative roles as transcription factors are based on the similarity of mat A-2 with the Podospora anserina SMR1 gene and an HMG motif present in the mat A-3 gene. In this work the yeast two-hybrid system was used to identify transcriptional activity and protein-protein interaction of N. crassa mat A-2 and mat A-3 genes. We observed that the mat A-3 protein alone is capable of weakly activating transcription of yeast reporter genes; it also binds with low specificity to the GAL1 promoter sequence, possibly due to its HMG domain. Our results also indicate that mat A-3 is capable to form homodimers, and interact with mat A-2. Interference on yeast growth was observed on some transformants suggesting a toxic action of the mat A-2 protein. Our data on pattern of interactions of mat proteins contributes towards understanding the control of vegetative and sexual cycles in filamentous fungi.
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Puberty is the fundamental period for bone mass (BM) acquisition. In this period mineralization is found to increase with levels of high bone formation. The critical years of intense bone anabolism deserve special attention, as adequate gain could minimize fracture risk in later years. The objective of this work was to study bone mineral content (BMC) and bone mineral density (BMD) in male adolescents with age bracket and maturation level. Sixty-one healthy male 10 to 19 year-olds were evaluated for calcium intake, weight, stature, BMI, puberty stage and BMC and BMD in the lumbar spine and femur. BM was measured by bone densitometry (DXA). Calcium intake was calculated by recording 3 days diet. Puberty stage was defined as per Tanner. Descriptive statistics was used with means and standard deviations, linear correlation, and analysis of variance for comparison between age groups, and the Tukey test (p<0.05). Linear correlation was positive and indicated body weight as the main correlation variable with BMD in both studied locations (p<0.01). BMC and BMD increased with age, differences were significant from 14 to 15 years, and when adolescents reached Tanner stage G4. These results showed a pronounced increase in bone mineralization, with the years after 14 to 15 being critical for BM acquisition in Brazilian adolescents.
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Densidade Óssea/fisiologia , Calcificação Fisiológica/fisiologia , Cálcio da Dieta/análise , Puberdade/fisiologia , Absorciometria de Fóton , Adolescente , Adulto , Distribuição por Idade , Índice de Massa Corporal , Brasil , Cálcio da Dieta/administração & dosagem , Criança , Fêmur/diagnóstico por imagem , Humanos , Vértebras Lombares/diagnóstico por imagem , Masculino , Valores de ReferênciaRESUMO
Puberty is the fundamental period for bone mass (BM) acquisition. In this period mineralization is found to increase with levels of high bone formation. The critical years of intense bone anabolism deserve special attention, as adequate gain could minimize fracture risk in later years. The objective of this work was to study bone mineral content (BMC) and bone mineral density (BMD) in male adolescents with age bracket and maturation level. Sixty-one healthy male 10 to 19 year-olds were evaluated for calcium intake, weight, stature, BMI, puberty stage and BMC and BMD in the lumbar spine and femur. BM was measured by bone densitometry (DXA). Calcium intake was calculated by recording 3 days diet. Puberty stage was defined as per Tanner. Descriptive statistics was used with means and standard deviations, linear correlation, and analysis of variance for comparison between age groups, and the Tukey test (p<0.05). Linear correlation was positive and indicated body weight as the main correlation variable with BMD in both studied locations (p<0.01). BMC and BMD increased with age, differences were significant from 14 to 15 years, and when adolescents reached Tanner stage G4. These results showed a pronounced increase in bone mineralization, with the years after 14 to 15 being critical for BM acquisition in Brazilian adolescents.
Mineralización ósea en adolescentes brasileños: años de máxima incorporación de masa ósea. La pubertad es un momento fundamental para la adquisición de la masa ósea (MO). En este período, la mineralización se encuentra en aumento en los niveles de formación ósea. Los años críticos de intenso anabolismo óseo necesitan de atención, porque el adecuado aumento de la masa ósea podría minimizar el riesgo de fracturas en los años posteriores. El objetivo de esta investigación fue estudiar el contenido mineral óseo (CMO) y la densidad mineral ósea (DMO) en adolescentes según el grupo de edad y el nível de maduración. Sesenta y un adolescentes saludables de 10 a 19 años fueron evaluados cuanto a la ingesta de calcio, peso, estatura, índice de masa corpórea (IMC), etapa puberal, CMO y DMO en la columna lumbar y en el fémur. La MO fue medida por densitometría ósea (DEXA). La ingesta de calcio fue calculada mediante un recordatorio de ingesta de tres días. La etapa puberal fue definida por los criterios de Tanner. Estadística descriptiva fue utilizada con media y desviación estándar, correlación linear y análisis de varianza para comparar los grupos y test de Tukey (p<0,05). Correlación linear fue positiva e indicó que el peso corporal fue la principal variable correlacionada con la DMO en los dos sitios estudiados (p<0,01). CMO y DMO aumentaron con la edad y las diferencias fueron considerables de los 14 a los 15 años, cuando los adolescentes alcanzaban la etapa G4 de Tanner. Estos resultados muestran un aumento pronunciado en la mineralización ósea; entre los 14 y 15 años fueron críticos para la adquisición de MO en adolescentes brasileños.
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Humanos , Masculino , Criança , Adolescente , Adulto , Densidade Óssea/fisiologia , Calcificação Fisiológica/fisiologia , Cálcio da Dieta/análise , Puberdade/fisiologia , Absorciometria de Fóton , Distribuição por Idade , Índice de Massa Corporal , Brasil , Cálcio da Dieta/administração & dosagem , Fêmur , Vértebras Lombares , Valores de ReferênciaRESUMO
Osteoporosis is considered one of the most serious public health diseases and studies show that it is a pediatric disease that manifests during senility. It is usually diagnosed in clinical practice by dual-energy x-ray absorptiometry (DXA). This exam has a high cost and it is difficult to apply to a pediatric population because specific equipment and special software are required. This study presents predictive equations to evaluate the bone mineral density (BMD) among male adolescents. To better predict the equations, some parameters were used as the bone age (by left hand and wrist x-ray), pubertal stages, weight, height and the lumbar spine and femur BMD from 61 healthy adolescents, ages 10 through 19 years. The prediction models were carried through analysis of multiple regressions stepwise. The results have indicated a prediction model for BMD with a coefficient of 0.87 and 0.80, respectively for the spine and the femoral regions. In conclusion, the results have confirmed that BMD depends on the skeletal age and the physical growth during adolescence. The proposed equations are easy to use, has a low operational cost, and the clarification rate is 75% and 65% for lumbar spine and femoral BMD, respectively.
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Densidade Óssea/fisiologia , Colo do Fêmur/diagnóstico por imagem , Vértebras Lombares/diagnóstico por imagem , Modelos Biológicos , Absorciometria de Fóton , Adolescente , Adulto , Antropometria , Índice de Massa Corporal , Criança , Colo do Fêmur/fisiologia , Humanos , Vértebras Lombares/fisiologia , Masculino , Valor Preditivo dos Testes , Análise de Regressão , Maturidade SexualRESUMO
Considerada um grave problema de saúde pública, estudos indicam que a osteoporose é uma doença pediátrica com manifestações clínicas apresentadas na senilidade. O diagnóstico de osteopenia/ osteoporose é normalmente feito na prática clínica através da densitometria óssea por atenuação de raio-x de dupla energia (DXA). O exame é de alto custo e de difícil aplicação em populações pediátricas em virtude do emprego de aparelhagem específica e software especial. O presente estudo propõe equações preditivas para avaliação da densidade mineral óssea (DMO) em adolescentes do sexo masculino. Foram recrutados 61 adolescentes saudáveis na faixa de 10 a 19 anos e obtidos a idade óssea (através do raio-x de mão e punho esquerdo), maturação sexual, o peso, a estatura, a DMO na coluna lombar e no fêmur proximal total. A estruturação dos modelos de predição foi realizada pela análise de regressão múltipla "stepwise". Os resultados indicaram modelos de predição para DMO com coeficientes de correlação de 0,87 para região da coluna e 0,80 para região femoral. Esses resultados confirmam que a DMO depende da idade esquelética e do crescimento físico durante a adolescência. As equações propostas são de fácil aplicação, baixo custo operacional e com poder explicativo superior a 75 por cento e 65 por cento, respectivamente para a DMO da coluna lombar e fêmur proximal total.
Assuntos
Humanos , Masculino , Criança , Adolescente , Adulto , Densidade Óssea/fisiologia , Colo do Fêmur , Vértebras Lombares , Modelos Biológicos , Absorciometria de Fóton , Antropometria , Índice de Massa Corporal , Valor Preditivo dos Testes , Análise de Regressão , Maturidade SexualRESUMO
OBJECTIVE: To verify the behavior of the mineral bone content and density in male adolescents according to age and secondary sexual characters. METHODS: 47 healthy adolescents between 10 and 19 years of age were assessed according to weight, height, body mass index, puberty stage, calcium intake, bone mineral density and content in the lumbar spine and in the proximal femur. The bone mass was measured through bone densitometries. The intake of calcium was calculated through a 3-day diet. The BMI (body mass index) was calculated with the Quetelet Index and the puberty stage was defined according to Tanner's criteria. The analysis used descriptive statistics such as average and standard deviation, and variance estimates to compare the different age groups. Moreover, the Tukey test was used to determine the significant differences. RESULTS: It was evident that the calcium intake in the different ages assessed has not reached the minimum value of 800 mg. The bone mineral density and content showed an increase after the age of 14, as well as when the teenagers reached the sexual maturation stage G4. The mineralization parameters showed a high level when the teenagers were in the G3 stage, however, without statistical significance. CONCLUSION: The results indicate an important level of bone mineralization during adolescence. Maturation levels superior to G3 have shown more mineralization. This study proves that the critical years for bone mass gain start after the age of 14-15 years or older.
Assuntos
Densidade Óssea/fisiologia , Cálcio da Dieta/análise , Puberdade/fisiologia , Maturidade Sexual/fisiologia , Absorciometria de Fóton , Adolescente , Distribuição por Idade , Índice de Massa Corporal , Cálcio da Dieta/administração & dosagem , Criança , Fêmur/diagnóstico por imagem , Humanos , Vértebras Lombares/diagnóstico por imagem , MasculinoRESUMO
OBJETIVO: Verificar o comportamento do conteúdo mineral ósseo e da densidade mineral óssea em adolescentes do sexo masculino em função da faixa etária e do nível maturacional dos caracteres sexuais secundários. MÉTODOS: 47 adolescentes saudáveis na faixa etária de 10 a 19 anos foram avaliados quanto a ingestão de cálcio, peso, estatura, índice de massa corporal, estágio puberal, densidade mineral óssea e conteúdo mineral ósseo na coluna e no fêmur proximal. A massa óssea foi mensurada através de densitometria óssea. A ingestão de cálcio foi calculada através de registro dietético de 3 dias. O índice de massa corporal foi calculado pelo índice de Quetelet, e o estágio puberal foi definido segundo os critérios de Tanner. Foi utilizada estatística descritiva, média e desvio padrão, análise de variância para comparação entre os grupos etários e teste de Tukey para localizar as diferenças significativas. RESULTADOS: A ingestão de cálcio não alcançou o valor mínimo de 800 mg em várias faixas etárias estudadas. A densidade mineral óssea e o conteúdo mineral ósseo demonstraram incrementos com o avançar da idade, indicando diferenças significativas a partir dos 14 anos, bem como quando os adolescentes atingiam os estágios de maturação sexual G4. Os parâmetros de mineralização revelaram aumento pronunciado quando os adolescentes atingiam G3, porém sem significado estatístico. CONCLUSÃO: Os resultados apontam um aumento importante na mineralização óssea durante a adolescência. A evidência de aumento na mineralização dos adolescentes foi percebida em níveis maturacionais superiores a G3. Os anos críticos para a aquisição da massa óssea neste estudo evidenciaram-se a partir dos 14-15 anos de idade.