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The introduction of quantum methods in spectroscopy can provide enhanced performance and technical advantages in the management of noise. We investigate the application of quantum illumination in a pump and probe experiment. Thermal lensing in a suspension of gold nanorods is explored using a classical beam as the pump and the emission from parametric downconversion as the probe. We obtain an insightful description of the behavior of the suspension under pumping with a method known to provide good noise rejection. Our findings are a further step toward investigating the effects of quantum light in complex plasmonic media.
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Musculoskeletal (MSK) disorders are associated with large impacts on patient's pain and quality of life. Conventional morphological imaging of tissue structure is limited in its ability to detect pain generators, early MSK disease, and rapidly assess treatment efficacy. Positron emission tomography (PET), which offers unique capabilities to evaluate molecular and metabolic processes, can provide novel information about early pathophysiologic changes that occur before structural or even microstructural changes can be detected. This sensitivity not only makes it a powerful tool for detection and characterization of disease, but also a tool able to rapidly assess the efficacy of therapies. These benefits have garnered more attention to PET imaging of MSK disorders in recent years. In this narrative review, we discuss several applications of multimodal PET imaging in non-oncologic MSK diseases including arthritis, osteoporosis, and sources of pain and inflammation. We also describe technical considerations and recent advancements in technology and radiotracers as well as areas of emerging interest for future applications of multimodal PET imaging of MSK conditions. Overall, we present evidence that the incorporation of PET through multimodal imaging offers an exciting addition to the field of MSK radiology and will likely prove valuable in the transition to an era of precision medicine.
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Imagem Multimodal , Doenças Musculoesqueléticas , Tomografia por Emissão de Pósitrons , Humanos , Doenças Musculoesqueléticas/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Imagem Multimodal/métodos , Compostos RadiofarmacêuticosRESUMO
BACKGROUND: Dental eruption is part of a set of children´s somatic growth phenomena. The worldwide accepted human dental eruption chronology is still based on a small sample of European children. However, evidence points to some population variations with the eruption at least two months later in low-income countries, and local standards may be useful. So, this study aimed to predict deciduous teeth eruption from 12 months of age in a Brazilian infant population. METHODS: We developed a cross-sectional study nested in four prospective cohorts - the Brazilian Ribeirão Preto and São Luís Cohort Study (BRISA) - in a sample of 3,733 children aged 12 to 36 months old, corrected by gestational age. We made a reference curve with the number of teeth erupted by age using the Generalized Additive Models for location, scale, and shape (GAMLSS) technique. The explanatory variable was the corrected children´s age. The dependent variable was the number of erupted teeth, by gender, evaluated according to some different outcome distributional forms. The generalized Akaike information criterion (GAIC) and the model residuals were used as the model selection criterion. RESULTS: The Box-Cox Power Exponential method was the GAMLSS model with better-fit indexes. Our estimation curve was able to predict the number of erupted deciduous teeth by age, similar to the real values, in addition to describing the evolution of children's development, with comparative patterns. There was no difference in the mean number of erupted teeth between the sexes. According to the reference curve, at 12 months old, 25% of children had four erupted teeth or less, while 75% had seven or fewer and 95% had 11 or fewer. At 24 months old, 5% had less than 12, and 75% had 18 or more. At 36 months old, around 50% of the population had deciduous dentition completed (20 teeth). CONCLUSION: The adjusted age was an important predictor of the number of erupted deciduous teeth. This outcome can be a variable incorporated into children's growth and development curves, such as weight and height curves for age to help dentists and physicians in the monitoring the children's health.
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Coorte de Nascimento , Dente Decíduo , Criança , Lactente , Humanos , Pré-Escolar , Estudos Transversais , Estudos de Coortes , Brasil/epidemiologia , Estudos ProspectivosRESUMO
PURPOSE: To develop and validate a method for B 0 $$ {B}_0 $$ mapping for knee imaging using the quantitative Double-Echo in Steady-State (qDESS) exploiting the phase difference ( Δ Î¸ $$ \Delta \theta $$ ) between the two echoes acquired. Contrary to a two-gradient-echo (2-GRE) method, Δ Î¸ $$ \Delta \theta $$ depends only on the first echo time. METHODS: Bloch simulations were applied to investigate robustness to noise of the proposed methodology and all imaging studies were validated with phantoms and in vivo simultaneous bilateral knee acquisitions. Two phantoms and five healthy subjects were scanned using qDESS, water saturation shift referencing (WASSR), and multi-GRE sequences. Δ B 0 $$ \Delta {B}_0 $$ maps were calculated with the qDESS and the 2-GRE methods and compared against those obtained with WASSR. The comparison was quantitatively assessed exploiting pixel-wise difference maps, Bland-Altman (BA) analysis, and Lin's concordance coefficient ( ρ c $$ {\rho}_c $$ ). For in vivo subjects, the comparison was assessed in cartilage using average values in six subregions. RESULTS: The proposed method for measuring Δ B 0 $$ \Delta {B}_0 $$ inhomogeneities from a qDESS acquisition provided Δ B 0 $$ \Delta {B}_0 $$ maps that were in good agreement with those obtained using WASSR. Δ B 0 $$ \Delta {B}_0 $$ ρ c $$ {\rho}_c $$ values were ≥ $$ \ge $$ 0.98 and 0.90 in phantoms and in vivo, respectively. The agreement between qDESS and WASSR was comparable to that of a 2-GRE method. CONCLUSION: The proposed method may allow B0 correction for qDESS T 2 $$ {T}_2 $$ mapping using an inherently co-registered Δ B 0 $$ \Delta {B}_0 $$ map without requiring an additional B0 measurement sequence. More generally, the method may help shorten knee imaging protocols that require an auxiliary Δ B 0 $$ \Delta {B}_0 $$ map by exploiting a qDESS acquisition that also provides T 2 $$ {T}_2 $$ measurements and high-quality morphological imaging.
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Joelho , Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , Imagens de Fantasmas , Joelho/diagnóstico por imagem , Articulação do Joelho/diagnóstico por imagem , ÁguaRESUMO
Recovering the original spectral line shapes from data obtained by instruments with extended transmission profiles is a basic tenet in spectroscopy. By using the moments of the measured lines as basic variables, we turn the problem into a linear inversion. However, when only a finite number of these moments are relevant, the rest of them act as nuisance parameters. These can be taken into account with a semiparametric model, which allows us to establish the ultimate bounds on the precision attainable in the estimation of the moments of interest. We experimentally confirm these limits with a simple ghost spectroscopy demonstration.
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BACKGROUND: Preterm birth is a leading cause of infant morbidity and mortality; its multifactorial causes are an obstacle to understanding etiology and pathogenesis. The importance of cytokines and inflammation in its etiology and association with the short cervix is nowadays well-proven. To date, there are no reliable biological or biochemical markers to predict preterm birth; even though the length of the cervix has high specificity, its sensitivity with the cervix below 2.5 cm is low. OBJECTIVE: We study the association of plasma cytokine levels and cervical length in search of predictors of preterm birth. STUDY DESIGN: We evaluated a total of 1400 pregnant women carrying a single fetus between 20 and 25 weeks of gestation, and 1370 of them after childbirth in a nested case-control study of a prenatal cohort. Eligible pregnant women were interviewed and submitted to obstetric morphological and transvaginal ultrasound with cervical length measurement, gynecological examination, and blood collection. Preterm birth occurred in 133 women, 129 included in the study, and a control group randomly selected at a 2:1 ratio. A total of 41 cytokines with a higher probability of being associated with preterm birth or being of significance during labor were determined. RESULTS: Cytokine and cervical length analysis by multivariate analysis of the conditional interference tree revealed that growth-related oncogene values of less than 2293 pg/mL were significantly associated with a cervical length of less than 2.5 cm. CONCLUSIONS: As well as a cervical length shorter than 2.5 cm, growth-related oncogene levels of less than 2293 pg/ml may be associated with an increased risk of PB. Analysis based on the association of biomarkers and of the interaction between cytokines is a promising pathway in search of a predictor of preterm birth.
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Nascimento Prematuro , Gravidez , Feminino , Recém-Nascido , Humanos , Nascimento Prematuro/diagnóstico , Colo do Útero/anatomia & histologia , Gestantes , Estudos Prospectivos , Estudos de Casos e Controles , Medida do Comprimento Cervical , PartoRESUMO
PURPOSE: [Formula: see text] mapping is a powerful tool for studying osteoarthritis (OA) changes and bilateral imaging may be useful in investigating the role of between-knee asymmetry in OA onset and progression. The quantitative double-echo in steady-state (qDESS) can provide fast simultaneous bilateral knee [Formula: see text] and high-resolution morphometry for cartilage and meniscus. The qDESS uses an analytical signal model to compute [Formula: see text] relaxometry maps, which require knowledge of the flip angle (FA). In the presence of [Formula: see text] inhomogeneities, inconsistencies between the nominal and actual FA can affect the accuracy of [Formula: see text] measurements. We propose a pixel-wise [Formula: see text] correction method for qDESS [Formula: see text] mapping exploiting an auxiliary [Formula: see text] map to compute the actual FA used in the model. METHODS: The technique was validated in a phantom and in vivo with simultaneous bilateral knee imaging. [Formula: see text] measurements of femoral cartilage (FC) of both knees of six healthy participants were repeated longitudinally to investigate the association between [Formula: see text] variation and [Formula: see text]. RESULTS: The results showed that applying the [Formula: see text] correction mitigated [Formula: see text] variations that were driven by [Formula: see text] inhomogeneities. Specifically, [Formula: see text] left-right symmetry increased following the [Formula: see text] correction ([Formula: see text] = 0.74 > [Formula: see text] = 0.69). Without the [Formula: see text] correction, [Formula: see text] values showed a linear dependence with [Formula: see text]. The linear coefficient decreased using the [Formula: see text] correction (from 24.3 ± 1.6 ms to 4.1 ± 1.8) and the correlation was not statistically significant after the application of the Bonferroni correction (p value > 0.01). CONCLUSION: The study showed that [Formula: see text] correction could mitigate variations driven by the sensitivity of the qDESS [Formula: see text] mapping method to [Formula: see text], therefore, increasing the sensitivity to detect real biological changes. The proposed method may improve the robustness of bilateral qDESS [Formula: see text] mapping, allowing for an accurate and more efficient evaluation of OA pathways and pathophysiology through longitudinal and cross-sectional studies.
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Articulação do Joelho , Imageamento por Ressonância Magnética , Humanos , Estudos Transversais , Imageamento por Ressonância Magnética/métodos , Articulação do Joelho/diagnóstico por imagem , Imageamento Tridimensional , Imagens de FantasmasRESUMO
AIM: To analyze the association between neonatal near miss and infant development at two years. METHODS: Data from two birth cohorts, one conducted in Ribeirão Preto (RP)/São Paulo and the other in São Luís (SL)/Maranhão, were used. The cognitive, motor and communication development of children was evaluated using the Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III). The following criteria were used for the definition of NNM: birth weight < 1,500 g, 5-min Apgar score < 7, gestational age < 32 weeks, and report of congenital malformations. The relationship between neonatal near miss and development was assessed using the weighted propensity score from the Inverse Probability of Treatment Weighting (IPTW). A directed acyclic graph was built to select the adjustment variables. RESULTS: A total of 1,050 mother-newborn dyads were evaluated in SL and 1,840 in RP. Regarding outcomes in SL and RP, respectively, 2.4% and 17.3% of the children were not competent in the cognitive domain, 12.1% and 13.3% in the receptive communication domain, 39.2% and 47.1% in the expressive communication domain, 20.7% and 12.6% in the fine motor domain, and 14.3% and 13.8% in the gross motor domain. The prevalence of neonatal near miss was 5.4% in SL and 4.3% in RP. Unadjusted analysis showed an association of neonatal near miss with fine motor development in SL and RP and with the cognitive, receptive communication, expressive communication, and gross motor domains only in RP. These associations remained after adjusted analysis. CONCLUSION: Neonatal near miss is a risk factor for developmental delays.
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Coorte de Nascimento , Near Miss , Recém-Nascido , Feminino , Humanos , Lactente , Fatores Socioeconômicos , Estudos de Coortes , Brasil/epidemiologia , Recém-Nascido de muito Baixo PesoRESUMO
BACKGROUND: Few studies have assessed dietary patterns (DPs) and the changes in these patterns over time in adults. The present study aimed to investigate whether possible changes in DPs in two assessments are associated with obesity and excess body fat. METHODS: A prospective study was conducted in which data were collected from 1082 adults of a Brazilian birth cohort during two periods 15 years apart (T1: 2002-2004; T2: 2016-2017). Food consumption was assessed in both periods using validated food frequency questionnaires. Three similar DPs were found in the two assessments, and adherence to these patterns was classified as prudent, risk or mixed. Nine DPs changes were defined. At T2, subjects with a body mass index ≥ 30.0 kg m- ² were classified as obese, and men and women with a body fat (BF) percentage ≥ 25.0 and ≥ 35.0, respectively, were classified as having excess BF. A directed acyclic graph was built to adjust the association for confounding variables. RESULTS: At T2, 34.4% of the subjects were obese and 61.4% had excess BF. In the adjusted analysis, the changes associated with obesity and excess BF were prudent-mixed (prevalence ratio [PR] 1.55; 95% confidence interval [CI] = 1.04-2.29 and PR = 1.35; 95% CI = 1.10-1.65), risk-risk (PR = 1.49; 95% CI = 1.03-2.13 and PR = 1.27; 95% CI = 1.04-1.53), risk-mixed (PR = 1.56; 95% CI = 1.05-2.31 and PR = 1.33; 95% CI = 1.07-1.63) and mixed-risk (PR = 1.61; 95% CI = 1.10-2.35 and PR = 1.29; 95% CI = 1.04-1.58). CONCLUSIONS: A decline in food quality over time or stagnation in an unhealthy DP can lead to obesity and excess BF.
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Coorte de Nascimento , Dieta , Masculino , Adulto , Humanos , Feminino , Dieta/efeitos adversos , Estudos Prospectivos , Brasil/epidemiologia , Obesidade/epidemiologia , Obesidade/etiologia , Índice de Massa Corporal , Tecido AdiposoRESUMO
We hypothesize that early events of diabetes and cardiovascular disease continuums would be ongoing and associated in adolescents. We investigated the association between the Insulin Resistance Phenotype and the Vascular Risk Phenotype at the end of the second decade of life and indirect pathways from social vulnerability, alcohol consumption, and body fat mass. It is a population-based study in the RPS cohort of 18-19 years (n = 2,515), São Luís, Brazil. The theoretical model analyzed the association between Insulin Resistance Phenotype and Vascular Risk Phenotype by sex, using structural equation modeling (SEM). The Insulin Resistance Phenotype was a latent variable deduced from the correlations of Triglyceride to HDL ratio, Triglyceride Glycemic index, and VLDL; the Vascular Risk Phenotype was deduced from Systolic Blood Pressure, Diastolic Blood Pressure, and Pulse Wave Velocity. The Insulin Resistance Phenotype was directly associated with the Vascular Risk Phenotype in males (standardized coefficient SC = 0.183; p < 0.001) and females (SC = 0.152; p < 0.001). The Insulin Resistance Phenotype was an indirect pathway in the association of alcohol consumption and higher values of fat mass index with the Vascular Risk Phenotype. VLDL presented the highest factor loading, appearing as a marker of insulin resistance linked to cardiovascular risk in young people. Lower values of socioeconomic status, harmful use of alcohol, and high body fat values were also associated with higher values of the two phenotypes. The association of the Insulin Resistance Phenotype with the Vascular Risk Phenotype suggests common pathophysiological mechanisms present in early events in the continuums of diabetes and cardiovascular disease in adolescence.
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Doenças Cardiovasculares , Resistência à Insulina , Masculino , Feminino , Humanos , Análise de Onda de Pulso , Índice de Massa Corporal , Pressão Sanguínea/fisiologia , Triglicerídeos , Fenótipo , Fatores de Risco , InsulinaRESUMO
Magnetic resonance fingerprinting (MRF) is a rapidly developing approach for fast quantitative MRI. A typical drawback of dictionary-based MRF is an explosion of the dictionary size as a function of the number of reconstructed parameters, according to the "curse of dimensionality", which determines an explosion of resource requirements. Neural networks (NNs) have been proposed as a feasible alternative, but this approach is still in its infancy. In this work, we design a deep learning approach to MRF using a fully connected network (FCN). In the first part we investigate, by means of simulations, how the NN performance scales with the number of parameters to be retrieved in comparison with the standard dictionary approach. Four MRF sequences were considered: IR-FISP, bSSFP, IR-FISP-B1 , and IR-bSSFP-B1 , the latter two designed to be more specific for B1+ parameter encoding. Estimation accuracy, memory usage, and computational time required to perform the estimation task were considered to compare the scalability capabilities of the dictionary-based and the NN approaches. In the second part we study optimal training procedures by including different data augmentation and preprocessing strategies during training to achieve better accuracy and robustness to noise and undersampling artifacts. The study is conducted using the IR-FISP MRF sequence exploiting both simulations and in vivo acquisitions. Results demonstrate that the NN approach outperforms the dictionary-based approach in terms of scalability capabilities. Results also allow us to heuristically determine the optimal training strategy to make an FCN able to predict T1 , T2 , and M0 maps that are in good agreement with those obtained with the original dictionary approach. k-SVD denoising is proposed and found to be critical as a preprocessing step to handle undersampled data.
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Aprendizado Profundo , Algoritmos , Encéfalo , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Imagens de FantasmasRESUMO
Preterm birth (PTB) and postpartum depression (PPD) are important public health issues, and although literature mainly supports the association between them, some reviews have highlighted methodological limitations in the studies in this field, restricting the interpretation of such finding. This study aimed at assessing the association between PTB and PPD, by comparing groups of preterm and full-term mothers in two Brazilian cities with contrasting sociodemographic indicators. This prospective convenience cohort study assessed 1421 women during pregnancy, at childbirth, and in the postpartum period. The Edinburgh Postnatal Depression Scale (EPDS) was administrated to assess PPD within 6 months after delivery and women were considered probably depressed if scores were EDPS ≥ 12. PTB was defined as the delivery before 37 completed weeks of pregnancy. A multivariate Poisson regression was used to estimate relative risk for PPD in mothers of preterm infants, and the final analysis models were adjusted for psychosocial variables, selected according to the directed acyclic graph (DAG) approach. Frequencies of PPD were not significantly different in mothers of preterm and full-term infants, in neither city. In the final adjusted model, PTB was not associated with PPD. The association between PTB and PPD was not confirmed in two large samples from two Brazilian cities with contrasting socioeconomic profile. However, maternal health during pregnancy plays an important role in predicting PPD. Prenatal care should promote maternal mental health as an effort towards decreasing unfavored outcomes for mothers, infants, and families.
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Depressão Pós-Parto , Nascimento Prematuro , Brasil/epidemiologia , Estudos de Coortes , Depressão Pós-Parto/diagnóstico , Depressão Pós-Parto/epidemiologia , Depressão Pós-Parto/psicologia , Feminino , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Gravidez , Nascimento Prematuro/epidemiologia , Estudos ProspectivosRESUMO
BACKGROUND: Allergic status has been strongly influenced by early exposures; however, allergic diseases are hard to measure in early life. Thus, this study proposed a latent variable allergy traits around the second year of life and analyzed pre- and perinatal factors associated with this phenomenon. METHODS: The study used data from the BRISA birth cohort, Ribeirão Preto, Brazil (n = 3644). The theoretical model included: family allergy (history of allergic rhinitis, atopic dermatitis, and asthma); gestational period variables (socioeconomic status, mother's skin color, pregestational body mass index - BMI, smoking, gestational diabetes, and hypertension); birth variables (gestational age, 5-minute Apgar score, birth weight, type of delivery), and early life factor (exclusive breast feeding). The outcome was allergy traits around the 2nd year of life, a latent variable deduced from the shared variance among medical diagnosis of allergic rhinitis, atopic dermatitis, and food allergy. The model was analyzed by structural equation modeling. RESULTS: Higher socioeconomic status (SC = 0.256; p < 0.001) and higher family allergy values (SC = 1.224; p < 0.001) were associated with higher allergy trait values. Hypertension during pregnancy was associated with higher values (SC = 0.170; p = 0.022) and exclusive breast feeding (SC = -0.192; p < 0.001) with low allergy trait values. CONCLUSION: Although socioeconomic and environmental factors were associated with allergy traits around the 2nd year of life, the family component of allergy was the exposure that best explained this outcome.
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Dermatite Atópica , Rinite Alérgica , Humanos , Pré-Escolar , Estudos de Coortes , Dermatite Atópica/epidemiologia , Dermatite Atópica/etiologia , Brasil/epidemiologia , Rinite Alérgica/epidemiologia , Rinite Alérgica/etiologiaRESUMO
PURPOSE: Single-sided 1 H-NMR is proposed for the estimation of morphological parameters of trabecular bone, and potentially the detection of pathophysiological alterations of bone structure. In this study, a new methodology was used to estimate such parameters without using an external reference signal, and to study intratrabecular and intertrabecular porosities, with a view to eventually scanning patients. METHODS: Animal trabecular bone samples were analyzed by a single-sided device. The Carr-Purcell-Meiboom-Gill sequence of 1 H nuclei of fluids, including marrow, confined inside the bone, was analyzed by quasi-continuous T2 distributions and separated into two 1 H pools: short and long T2 components. The NMR parameters were estimated using models of trabecular bone structure, and compared with the corresponding micro-CT. RESULTS: Without any further assumptions, the internal reference parameter (short T2 signal intensity fraction) enabled prediction of the micro-CT parameters BV/TV (volume of the trabeculae/total sample volume) and BS/TV (external surface of the trabeculae/total sample volume) with linear correlation coefficient >0.80. The assignment of the two pools to intratrabecular and intertrabecular components yielded an estimate of average intratrabecular porosity (33 ± 5)%. Using the proposed models, the NMR-estimated BV/TV and BS/TV were found to be linearly related to the corresponding micro-CT values with high correlation (>0.90 for BV/TV; >0.80 for BS/TV) and agreement coefficients. CONCLUSION: Low-field, low-cost portable devices that rely on intrinsic magnetic field gradients and do not use ionizing radiation are viable tools for in vitro preclinical studies of pathophysiological structural alterations of trabecular bone.
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Osso e Ossos , Osso Esponjoso , Animais , Osso e Ossos/diagnóstico por imagem , Osso Esponjoso/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Porosidade , Microtomografia por Raio-XRESUMO
OBJECTIVE: Few studies are focused on sugar consumption around the first 1000 d of life. Thus, this work modelled the pathways linking the consumption of sugary drinks in pregnancy and maternal pre-gestational BMI to early child's exposure to products with high sugar content and to BMI z-score in the second year of life. DESIGN: BRISA cohort, São Luís, Brazil was used from the baseline to the follow-up at the second year of life. SETTING: A theoretical model was constructed to analyse associations between variables from prenatal period (socio-economic status, age, frequency of sugary drinks consumption during pregnancy and pre-gestational BMI), birth weight, exclusive breast-feeding and two outcomes: higher calories from products with added sugar as a percentage of the total daily energy intake and BMI z-score at follow-up at the first 2 years of life, using structural equation modelling. PARTICIPANTS: Data of pregnant women (n 1136) and their offspring. RESULTS: Higher pre-gestational BMI (standardised coefficient (SC) = 0·100; P = 0·008) and higher frequency of sugary drinks consumption during pregnancy (SC = 0·134; P < 0·001) resulted in high percentage of daily calories from products with added sugar in the second year of child, although no yet effect was observed on offspring weight at that time. CONCLUSIONS: Maternal obesity and sugary drinks consumption in pregnancy increased the risk of early exposure (before to 2 years) and high exposure of child to added sugar, showing perpetuation of the unhealthy dietary behaviours in the first 1000 d of life.
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Ingestão de Energia , Açúcares , Peso ao Nascer , Índice de Massa Corporal , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , GravidezRESUMO
BACKGROUND: The excess adiposity, even in the absence of diseases, is responsible for a decline in pulmonary function, which is considered a predictor of mortality and a risk factor for diseases in several epidemiological studies. However, studies on the association between obesity and pulmonary function have found only few associations or inconclusive results. The aim of the study is to evaluate the association between body composition and spirometric parameters, comparing simple obesity measures such as body mass index (BMI) and waist circumference with more precise body composition measurements such as dual-energy X-ray absorptiometry (DXA) and air-displacement plethysmography (BOD POD). METHODS: This is an observational, cross-sectional study that used data from the 1978/79 Ribeirão Preto birth cohort (São Paulo, Brazil). The study included 1746 participants from the 5th follow-up of the cohort. Linear regressions were calculated to evaluate the association between BMI, waist circumference, waist-height ratio (WHtR), BOD POD- and DXA-measured fat mass percentage, and spirometric parameters FEV1, and FVC. RESULTS: For every 1-kg/m2 BMI increase, FVC decreased by 13 ml in males and by 6 ml in females and FEV1 decreased by 11 ml and 5 ml, respectively. Regarding body composition measurements, for a 1% increase in fat mass assessed by BOD POD, FVC decreased by 16 ml in males and by 8 ml in females and FEV1 decreased by 13 ml and 7 ml, respectively. Hence, negative associations between body measurements and FEV1 and FVC were observed in both genders, especially when using the fat mass measurement and were more expressive in men. CONCLUSION: The anthropometric and body composition parameters were negatively associated with the spirometric variables FVC and FEV1. We have also observed that simple measures such as waist-height ratio were sufficient to detect the association of body composition with pulmonary function reduction.
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Composição Corporal/fisiologia , Pulmão/fisiologia , Absorciometria de Fóton , Adulto , Antropometria , Índice de Massa Corporal , Brasil , Estudos Transversais , Feminino , Volume Expiratório Forçado/fisiologia , Humanos , Modelos Lineares , Masculino , Fatores de Risco , Espirometria , Capacidade Vital/fisiologia , Circunferência da Cintura/fisiologiaRESUMO
Nuclear Magnetic Resonance (NMR) is a well-suited methodology to study bone composition and structural properties. This is because the NMR parameters, such as the T2 relaxation time, are sensitive to the chemical and physical environment of the 1H nuclei. Although magnetic resonance imaging (MRI) allows bone structure assessment in vivo, its cost limits the suitability of conventional MRI for routine bone screening. With difficulty accessing clinically suitable exams, the diagnosis of bone diseases, such as osteoporosis, and the associated fracture risk estimation is based on the assessment of bone mineral density (BMD), obtained by the dual-energy X-ray absorptiometry (DXA). However, integrating the information about the structure of the bone with the bone mineral density has been shown to improve fracture risk estimation related to osteoporosis. Portable NMR, based on low-field single-sided NMR devices, is a promising and appealing approach to assess NMR properties of biological tissues with the aim of medical applications. Since these scanners detect the signal from a sensitive volume external to the magnet, they can be used to perform NMR measurement without the need to fit a sample inside a bore of a magnet, allowing, in principle, in vivo application. Techniques based on NMR single-sided devices have the potential to provide a high impact on the clinical routine because of low purchasing and running costs and low maintenance of such scanners. In this review, the development of new methodologies to investigate structural properties of trabecular bone exploiting single-sided NMR devices is reviewed, and current limitations and future perspectives are discussed.
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Doenças Ósseas/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Absorciometria de Fóton/métodos , Animais , Densidade Óssea/fisiologia , Osso Esponjoso/diagnóstico por imagem , Fraturas Ósseas/diagnóstico por imagem , Humanos , Osteoporose/diagnóstico por imagemRESUMO
The characterization of quantum features in large Hilbert spaces is a crucial requirement for testing quantum protocols. In the continuous variable encoding, quantum homodyne tomography requires an amount of measurement that increases exponentially with the number of involved modes, which practically makes the protocol intractable even with few modes. Here, we introduce a new technique, based on a machine learning protocol with artificial neural networks, that allows us to directly detect negativity of the Wigner function for multimode quantum states. We test the procedure on a whole class of numerically simulated multimode quantum states for which the Wigner function is known analytically. We demonstrate that the method is fast, accurate, and more robust than conventional methods when limited amounts of data are available. Moreover, the method is applied to an experimental multimode quantum state, for which an additional test of resilience to losses is carried out.
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Research pertaining to exposure of humans to per- and polyfluorinated alkyl substances (PFASs) has received considerable public and regulatory attention in recent years. Although several studies have reported exposure to PFASs by populations in North America and western Europe, such information is still scarce in Latin America, including Brazil. In this study, concentrations of thirteen PFASs were determined in whole blood collected during the second trimester from 252 pregnant Brazilian women. This is a nested case-control study within the Brazilian Ribeirao Preto and Sao Luiz Birth Cohort Study (BRISA) with selected birth outcomes cases (n = 63) and matched controls (n = 189). PFASs concentrations were associated with conditions including preeclampsia, birth weight (BW), preterm birth, and intrauterine growth restriction (IUGR). Among PFASs measured, perfluorooctane sulfonate (PFOS) was found at the highest concentration (range: 1.06-106 ng mL-1 with a median value of 3.41 ng mL-1) which was followed by perfluorooctanoic acid (PFOA, range: 0.11-2.77 ng mL-1 with a median value of 0.20 ng mL-1). A significant positive association of PFOS and PFOA concentrations with fetal growth restriction (p < 0.05) was found. This is the first study to assess whole blood concentrations of PFASs and their effect on fetal growth in pregnant Brazilian women.
Assuntos
Ácidos Alcanossulfônicos , Poluentes Ambientais , Fluorocarbonos , Nascimento Prematuro , Brasil , Caprilatos/toxicidade , Estudos de Casos e Controles , Estudos de Coortes , Europa (Continente) , Feminino , Desenvolvimento Fetal , Fluorocarbonos/toxicidade , Humanos , Recém-Nascido , América do Norte , GravidezRESUMO
PURPOSE: Non-resective pharyngoplasty techniques have been shown to be effective to treat oropharyngeal collapse in patients affected by obstructive sleep apnea-hypopnea syndrome (OSAHS). The aim of our study is to evaluate outcome predictors in a cohort of patients affected by OSAHS and treated with non-resective pharyngoplasty, including variation of pharyngeal measures at the end of the surgical procedure. METHODS: A cohort of patients affected by OSAHS, with palatal or lateral pharyngeal wall collapse, who underwent non-resective pharyngoplasty, were enrolled between 2014 and 2017. Surgical procedures encompassed non-resective pharyngoplasty by expansion sphincter pharyngoplasty (ESP) or barbed antero-lateral pharyngoplasty with barbed reposition pharyngoplasty (BRP) or barbed suspension pharyngoplasty (BSP) techniques, eventually associated with nasal surgery. Pharyngeal measures were recorded intraoperatively and their variation at the end of the procedure was considered. Surgical success was evaluated at least 6 months after surgery with respiratory polygraphy and ESS questionnaire. Outcome predictors were examined by multivariable logistic regression and ROC curve analysis. RESULTS: Seventy patients met the study inclusion criteria. ESP, BRP, and BSP in a uni-/multilevel setting led to significant improvement of all respiratory polygraphic parameters and daily sleepiness (p < 0.0001). Outcome analysis showed that greater variation of antero-posterior pharyngeal measure was associated with success (p = 0.01), with an optimal cutoff value of 8.5 mm; low AHIpre, high ESSpre, and antero-lateral pharyngoplasty with barbed sutures were associated with a higher rate of cure (p < 0.05). CONCLUSIONS: Non-resective pharyngoplasty is effective in treating OSAHS patients affected by palatal or lateral pharyngeal wall collapse, and intraoperative variation of antero-posterior width may be a useful tool to predict surgical success.