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OBJECTIVE: Excess visceral adipose tissue (VAT) is a major risk factor for metabolic syndrome (MetS) and clinical guidelines have been proposed to define VAT levels associated with increased risk. The aim was to standardize VAT measures between two dual-energy x-ray absorptiometry (DXA) manufacturers who provide different VAT estimates to support standardization of measures across imaging modalities. METHODS: Scans from 114 individuals (ages 18-81 years) on GE HealthCare (GEHC) and Hologic DXA systems were compared via Deming regression to standardize VAT between the two systems, validated in a separate sample (n = 15), with κ statistics to assess agreement of VAT measurements for classifying patients into risk categories. RESULTS: The GEHC and Hologic VAT measures were highly correlated and validated in the separate data set (r2 = 0.97). VAT area measures substantially agreed for metabolic risk classification (weighted κ = 0.76) with no significant differences in the population mean values. CONCLUSIONS: VAT measures can be estimated from GEHC and Hologic scans that classify individuals in a substantially similar way into metabolic risk categories, and systematic bias between the measures can be removed using simple regression equations. These findings allow for DXA VAT measures to be used in complement to other imaging modalities, regardless of whether scans used GEHC or Hologic systems.
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Tejido Adiposo , Grasa Intraabdominal , Humanos , Grasa Intraabdominal/diagnóstico por imagen , Rayos X , Absorciometría de Fotón/métodos , Estándares de Referencia , Factores de RiesgoRESUMEN
OBJECTIVE: The National Health and Nutrition Examination Survey (NHANES) characterizes body composition representative of the US population using dual-energy x-ray absorptiometry (DXA) scans. These population-level trends of abdominal subcutaneous and visceral adipose tissue (SAT and VAT) are useful for identifying measures associated with increased disease risk. Recently, VAT and SAT data collected by Hologic DXA in NHANES were published online; however, there are known differences in the absolute calibration of DXA systems by make. The purpose of this study was to create reference tables suitable for calculating z scores and percentile values for GE HealthCare (GEHC) DXA systems. METHODS: DXA scans were acquired on participants aged 8 to 59 years using Hologic systems. DXA measures were converted to GEHC and described using the least median squares curve fitting method in pediatrics (aged <20 years) and adults (aged 20-59 years). RESULTS: A total of 11,972 adults and 7298 pediatrics were included for this analysis. Adult and pediatric curves were generated by sex and by ethnicity (non-Hispanic White, non-Hispanic Black, Hispanic, Asian, Other) and were derived as a function of age. CONCLUSIONS: These results show the ability to generate VAT and SAT reference data for GEHC systems using Hologic DXA data representative of the US youth and adult population.
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Composición Corporal , Grasa Intraabdominal , Adulto , Adolescente , Humanos , Niño , Absorciometría de Fotón/métodos , Encuestas Nutricionales , Grasa Intraabdominal/diagnóstico por imagen , Etnicidad , Tejido AdiposoRESUMEN
In recent years with regard to the development of nanotechnology and neural stem cell discovery, the combinatorial therapeutic strategies of neural progenitor cells and appropriate biomaterials have raised the hope for brain regeneration following neurological disorders. This study aimed to explore the proliferation and neurogenic effect of PLGA and PLGA-PEG nanofibers on human SH-SY5Y cells in in vitro condition. Nanofibers of PLGA and PLGA-PEG biomaterials were synthesized and fabricated using electrospinning method. Physicochemical features were examined using HNMR, FT-IR, and water contact angle assays. Ultrastructural morphology, the orientation of nanofibers, cell distribution and attachment were visualized by SEM imaging. Cell survival and proliferation rate were measured. Differentiation capacity was monitored by immunofluorescence staining of Map-2. HNMR, FT-IR assays confirmed the integration of PEG to PLGA backbone. Water contact angel assay showed increasing surface hydrophilicity in PLGA-PEG biomaterial compared to the PLGA substrate. SEM analysis revealed the reduction of PLGA-PEG nanofibers' diameter compared to the PLGA group. Cell attachment was observed in both groups while PLGA-PEG had a superior effect in the promotion of survival rate compared to other groups (p < .05). Compared to the PLGA group, PLGA-PEG increased the number of Ki67+ cells (p < .01). PLGA-PEG biomaterial induced neural maturation by increasing protein Map-2 compared to the PLGA scaffold in a three-dimensional culture system. According to our data, structural modification of PLGA with PEG could enhance orientated differentiation and the dynamic growth of neural cells.
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Materiales Biocompatibles , Nanofibras , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Proliferación Celular , Humanos , Nanofibras/química , Neurogénesis , Espectroscopía Infrarroja por Transformada de Fourier , Andamios del Tejido/químicaRESUMEN
OBJECTIVES: As rates of obesity around the world have increased, so has the detection of high level of liver fat in children and adolescents. This may put them at risk for cardiovascular disease later in life. This analysis of a cross-sectional population-based study of children and adolescents evaluated demographic and lifestyle determinants of percent liver fat. METHODS: Healthy participants (123 girls and 99 boys aged 5-17 years) recruited by convenience sampling in three locations completed questionnaires, anthropometric measurements, and dual X-ray absorptiometry and magnetic resonance imaging (MRI) assessment. General linear models were applied to estimate the association of demographic, anthropometric, and dietary factors as well as physical activity with MRI-based percent liver fat. RESULTS: The strongest predictor of liver fat was body mass index (BMI; p < 0.0001); overweight and obesity were associated with 0.5% and 1% higher liver fat levels. The respective adjusted mean percent values were 2.9 (95% CI 2.7, 3.1) and 3.4 (95% CI 3.2, 3.6) as compared to normal weight (2.4; 95% CI 2.3, 2.6). Mean percent liver fat was highest in Whites and African Americans, intermediate in Hispanic, and lowest among Asians and Native Hawaiians/Pacific Islanders (p < 0.0001). Age (p = 0.67), sex (p = 0.28), physical activity (p = 0.74), and diet quality (p = 0.70) were not significantly related with liver fat. CONCLUSIONS: This study in multiethnic children and adolescents confirms the strong relationship of BMI with percent liver fat even in a population with low liver fat levels without detecting an association with age, sex, and dietary or physical activity patterns.
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Synapses are touted as the main structural and functional components of neural cells within in the nervous system, providing tissue connectivity and integration via the formation of perineuronal nets. In the present study, we evaluated the synaptogenic activity of electrospun PLGA and PLGA-PEG nanofibers on human SH-SY5Y cells after 14 days in vitro. Electrospun PLGA and PLGA-PEG nanofibers were fabricated and physicochemical properties were examined using the HNMR technique. The cells were classified into three random groups, i.e., control (laminin-coated surface), PLGA, and PLGA-PEG. Scaffolds' features, cell morphology, attachment, and alignment were monitored by SEM imaging. We performed MTT assay to measure cell survival rate. To evaluate neurite formation and axonal outgrowth, cells were stained with an antibody against ß-tubulin III using immunofluorescence imaging. Antibodies against synapsin-1 and synaptophysin were used to explore the impact of PLGA and PLGA-PEG scaffolds on synaptogenesis and functional activity of synapses. According to SEM analysis, the PLGA-PEG scaffold had less thick nanofibers compared with the PLGA scaffold. Cell attachment, expansion, neurite outgrowth, and orientation were promoted in the PLGA-PEG group in comparison with the PLGA substrate (p < 0.05). MTT assay revealed that both scaffolds did not exert any neurotoxic effects on cell viability. Notably, PLGA-PEG surface increased cell viability compared to PLGA by time (p < 0.05). Immunofluorescence staining indicated an increased ß-tubulin III level in the PLGA-PEG group days coincided with axonal outgrowth and immature neuron marker after seven compared with the PLGA and control groups (p < 0.05). Based on our data, both synaptogenesis and functional connectivity were induced in cells plated on the PLGA-PEG surface that coincide with the increase of synapsin-1 and synaptophysin in comparsion with the PLGA and control groups (p < 0.05). Taken together, our results imply that the PLGA-PEG nanofibers could provide the desirable microenvironment to develop perineuronal net formation, contributing to efficient synaptogenesis and neuron-to-neuron crosstalk.
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Nanofibras/química , Poliésteres/química , Polietilenglicoles/química , Sinapsis/efectos de los fármacos , Andamios del Tejido/química , Línea Celular Tumoral , Supervivencia Celular , Humanos , Nanofibras/efectos adversos , Neuritas/efectos de los fármacos , Neuritas/metabolismo , Poliésteres/efectos adversos , Polietilenglicoles/efectos adversos , Sinapsis/metabolismo , Sinapsinas/metabolismo , Sinaptofisina/metabolismo , Ingeniería de Tejidos/métodos , Andamios del Tejido/efectos adversos , Tubulina (Proteína)/metabolismoRESUMEN
Background: Magnesium deficiency plays a key role in obesity and decreases insulin sensitivity. In our previous study, significant evidence was provided for the contribution of oral Mg supplement that could improve insulin sensitivity and body weight in animal trials. The purpose of the present study was to investigate the effects of an herbal supplement containing 300 mg magnesium sulfate on lipid profile, as well as insulin resistance and secretion in overweight patients. Methods: Seventy overweight non-diabetic volunteers with Body Mass Index (BMI) >28 kg/m2 were included in a randomized double blind placebo-controlled clinical trial (ethic number HUMS REC.1394.57) and registered in Iranian Registry of Clinical Trials (IRCT2012110124756N2 with registration number 24756). They received either placebo or an herbal supplement capsule containing 300 mg magnesium sulfate (MgSO4) for 6 months on a daily basis. Metabolic control, lipid profile and magnesium status were determined at baseline and every three months. Student t-test, repeated measure ANOVA and ANCOVA were used to compare the groups. Results: There was no significant difference between groups before intervention, but daily Mg supplement for 6 months significantly improved fasting insulin level (6.71±0.11 to 6.27±0.3 three months after Mg therapy, p<0.01 vs. 6.41±0.11 in control group (5.83±0.063) six months after Mg therapy, p< 0.0001), HOMA-IR (1.52±0.03 )in control group to 1.36±0.03 after three months Mg therapy, p<0.05 vs 1.37±0.05 in control group to 1.22±0.02 six months after Mg therapy, p< 0.05), high density lipoprotein cholesterol (HDL) (43.57±0.82 in control group to 43.91±1.92 three months after Mg therapy, p<0.001vs 43.57±0.82 in control group to 46±0.88 six months after Mg therapy, <0.01), triglyceride (TG) (163.17±6.1 in control group to 141.2±5.84 six months after g therapy, p<0.05) and low density lipoprotein cholesterol (LDL) (112.62±3.41 in control group to 104.42±2.35 six months after Mg therapy, p<0.05). Conclusion: Oral herbal supplement containing MgSO4 (300 mg/day) could improve plasma insulin level, lipid profile, and insulin resistance in non-diabetic overweight volunteers.
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Purpose To investigate the combination of mammography radiomics and quantitative three-compartment breast (3CB) image analysis of dual-energy mammography to limit unnecessary benign breast biopsies. Materials and Methods For this prospective study, dual-energy craniocaudal and mediolateral oblique mammograms were obtained immediately before biopsy in 109 women (mean age, 51 years; range, 31-85 years) with Breast Imaging Reporting and Data System category 4 or 5 breast masses (35 invasive cancers, 74 benign) from 2013 through 2017. The three quantitative compartments of water, lipid, and protein thickness at each pixel were calculated from the attenuation at high and low energy by using a within-image phantom. Masses were automatically segmented and features were extracted from the low-energy mammograms and the quantitative compartment images. Tenfold cross-validations using a linear discriminant classifier with predefined feature signatures helped differentiate between malignant and benign masses by means of (a) water-lipid-protein composition images alone, (b) mammography radiomics alone, and (c) a combined image analysis of both. Positive predictive value of biopsy performed (PPV3) at maximum sensitivity was the primary performance metric, and results were compared with those for conventional diagnostic digital mammography. Results The PPV3 for conventional diagnostic digital mammography in our data set was 32.1% (35 of 109; 95% confidence interval [CI]: 23.9%, 41.3%), with a sensitivity of 100%. In comparison, combined mammography radiomics plus quantitative 3CB image analysis had PPV3 of 49% (34 of 70; 95% CI: 36.5%, 58.9%; P < .001), with a sensitivity of 97% (34 of 35; 95% CI: 90.3%, 100%; P < .001) and 35.8% (39 of 109) fewer total biopsies (P < .001). Conclusion Quantitative three-compartment breast image analysis of breast masses combined with mammography radiomics has the potential to reduce unnecessary breast biopsies. © RSNA, 2018 Online supplemental material is available for this article.
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Enfermedades de la Mama/diagnóstico por imagen , Enfermedades de la Mama/patología , Mamografía/métodos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Adulto , Anciano , Anciano de 80 o más Años , Biopsia , Diagnóstico Diferencial , Femenino , Humanos , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Sensibilidad y EspecificidadRESUMEN
OBJECTIVE: The aim of this study was to evaluate the effect of agents available in whitening toothpastes (Crest® and Sensodyne®) in vitro on the force decay of elastomeric chains used in orthodontics. MATERIALS AND METHODS: A total of 300 specimens of elastomeric chains were divided into five groups (n = 60) and were evaluated. These groups included (1) the regular Crest® toothpaste and distilled water solution, (2) whitening Crest® toothpaste and distilled water solution, (3) regular Sensodyne® toothpaste and distilled water solution, (4) whitening Sensodyne® toothpaste and distilled water solution, and (5) distilled water as a control group. The samples' force was measured using Instron at intervals of 0, 1, 7, 14, 21, and 28 days. Data were analyzed by SPSS software. RESULTS: At the initial time point, the difference in the force values of elastomeric chain between any of the groups was not significant (P > 0.05). On the 1st day, there was a significant difference (P < 0.05) between all groups except the groups of whitening Crest®, regular, and whitening Sensodyne® (P > 0.05). On days 7, 14, and 28, the rate of decline for all groups was statistically significant (P < 0.05). CONCLUSIONS: According to the results obtained in the present study, it seems that toothpastes without whitening agents have less effect on force decay of elastomeric chain over time.
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BACKGROUND: Nursing education is mostly conducted through electronic educational programs. We aimed at assessing the Iranian postgraduate nursing students' skills and attitudes regarding the electronic education. MATERIALS AND METHODS: Ninety-seven postgraduate nursing students were surveyed using questionnaires assessing their individual-social and educational characteristics, electronic education skills, and attitudes toward the electronic education. RESULTS: Scores of the students' skills in using computer and the Internet were significantly associated with gender and the number of hours working with computer and the Internet at home and work. CONCLUSION: Prerequisites for performing electronic education programs are present at moderate levels in Iran.