Practice changing standardization of lower extremity lymphedema quantitative measurements with in... more Practice changing standardization of lower extremity lymphedema quantitative measurements with integrated patient reported outcomes will likely refine and redefine the optimal risk-reduction strategies to diminish the devastating limb-related dysfunction and morbidity associated with treatment of gynecologic cancers. The National Cancer Institute brought together a diverse group of cancer treatment, therapy and patient reported outcomes experts to discuss the current state-ofthe-science in lymphedema evaluation with the potential goal of incorporating new strategies for optimal evaluation of lymphedema in future developing gynecologic clinical trials. The key discussions are outlined in this report.
Human milk (HM) carbohydrates may affect infant appetite regulation, breastfeeding patterns, and ... more Human milk (HM) carbohydrates may affect infant appetite regulation, breastfeeding patterns, and body composition (BC). We investigated relationships between concentrations/calculated daily intakes (CDI) of HM carbohydrates in first year postpartum and maternal/term infant BC, as well as breastfeeding parameters. BC of dyads (n = 20) was determined at 2, 5, 9, and/or 12 months postpartum using ultrasound skinfolds (infants) and bioelectrical impedance spectroscopy (infants/mothers). Breastfeeding frequency, 24-h milk intake and total carbohydrates (TCH) and lactose were measured to calculate HM oligosaccharides (HMO) concentration and CDI of carbohydrates. Statistical analysis used linear regression/mixed effects models; results were adjusted for multiple comparisons. Higher TCH concentrations were associated with greater infant length, weight, fat-free mass (FFM), and FFM index (FFMI), and decreased fat mass (FM), FM index (FMI), %FM and FM/FFM ratio. Higher HMO concentrations were associated with greater infant FFM and FFMI, and decreased FMI, %FM, and FM/FFM ratio. Higher TCH CDI were associated with greater FM, FMI, %FM, and FM/FFM ratio, and decreased infant FFMI. Higher lactose CDI were associated with greater FM, FMI, %FM, and FM/FFM, ratio and decreased FFMI. Concentrations and intakes of HM carbohydrates differentially influence development of infant BC in the first 12 months postpartum, and may potentially influence risk of later obesity via modulation of BC.
Journal of Gastroenterology and Hepatology, Sep 1, 2018
Introduction: Hepatocellular carcinoma (HCC) is now the second leading cause of cancer mortality ... more Introduction: Hepatocellular carcinoma (HCC) is now the second leading cause of cancer mortality worldwide. It is most commonly diagnosed in individuals with established liver cirrhosis related to chronic hepatitis B virus infection (CHB), chronic hepatitis C virus infection (CHC), alcohol, and, increasingly, non-alcoholic fatty liver disease (NAFLD) or nonalcoholic steatohepatitis (NASH). However, the incidence of HCC is also rising in patients without preexisting cirrhosis, notably associated with NAFLD, CHB, type 2 diabetes, or the metabolic syndrome. Aim: We aimed to describe the characteristics of patients diagnosed with HCC at an Australian tertiary hospital over a 40-month period. Methods: The HCC database of the hepatology service was reviewed to establish clinical and sociodemographic characteristics of patients with HCC. Available data included age at diagnosis, mode of diagnosis, anthropometric and biochemical characteristics, etiology and severity of background liver disease, sex, treatments, and survival. Descriptive data are reported as means (standard deviation) or median (interquartile range), and comparisons of patients by sex, HCC etiology, and ethnicity, performed using the independent t test or analysis of variance for normally distributed variables and Mann-Whitney U or Kruskal-Wallis test for non-normally distributed data. Results: One hundred and sixty-one patients were diagnosed with HCC using radiological imaging criteria +/À serum alphafetoprotein levels in most patients. HCC was confirmed histologically from specimens obtained during HCC ablation procedures or the explanted liver at the time of transplantation in 30%. The median age of the patients was 62 years (IQR, 54-76), with the youngest aged 33 years. Most (81.4%) were male, 82.6% were cirrhotic, 32% had diabetes, 35% were obese (47% overweight/obese), and 42% had imaging-diagnosed fatty liver. The most common etiologies were alcohol-related liver disease, CHC, CHB, NAFLD/NASH, or HFE-related hereditary hemochromatosis alone or in combinations. Represented ethnicities included Caucasian (81%), Indigenous Australians/New Zealanders (6%), Chinese (4%), other Asian (4%), and African (2%). Cirrhotic patients with HCC had higher body mass index (BMI) (29.0 [7.1] vs 24.9 [4.6] kg/m 2 ) and INR (1.2 [0.2] vs 1.08 [0.1]) but lower fibrinogen (3.7 [1.3] vs 5.0 [1.4] g/L), platelet count (156 [89] vs 277 [89] × 10 9 ), and serum triglyceride levels (1.3 [0.7] vs 2.1 [1.4] mmol/L) than non-cirrhotic patients (P < 0.05 for all). Caucasian, Indigenous, and other Asian patients with HCC had greater BMI than African, Indian, and Chinese patients with HCC (median, 27.9 [IQR, 23.4-33.5] kg/m 2 vs 22.4 [IQR, 21.7-28.0] kg/m 2 , P = 0.03). Apart from lower high-density lipoprotein cholesterol (HDL-C) in male patients with HCC (1.0 [0.4] vs 1.4 [0.7] mmol/L), there was no other difference in anthropometric and biochemical characteristics between the sexes. There was no difference in serum alphafetoprotein levels based on sex, a cirrhosis diagnosis, or ethnicity in the HCC patients (P > 0.05). Excessive alcohol intake was associated with a younger age at diagnosis of HCC regardless of other hepatic comorbidities (60 [8] vs 65 [12] years, P = 0.004), particularly if alcohol and CHC were comorbid factors (56 [6] vs 65 [10] years, P < 0.001). By contrast, patients with NASH or metabolic syndrome-associated HCC were significantly older than patients with other HCC etiologies (71 [8] vs 60 [9] years, P < 0.001). Conclusions: Patients with HCC were predominantly Caucasian and had underlying cirrhosis. Caucasian patients, Indigenous patients from Australia or New Zealand, and non-Chinese, non-Indian patients with HCC were more likely to be overweight or obese than other HCC patients. Excessive alcohol consumption was associated with younger age at development of HCC, while NASH-or metabolic syndrome-associated HCC was associated with a diagnosis of HCC in older age.
D-optimal designs for nonlinear fixed and mixed effects models are explored, and the theory is ap... more D-optimal designs for nonlinear fixed and mixed effects models are explored, and the theory is applied to the measurement and analysis of bioelectrical impedance. Bioimpedance is known to vary more at extreme frequencies than others. D-optimal designs that account for this variation, and also possible mis-specification of initial parameter estimates, are considered in an attempt to find designs that will provide good parameter estimates in practice.
Hypothermia has been proven as an effective rescue therapy for infants with moderate or severe ne... more Hypothermia has been proven as an effective rescue therapy for infants with moderate or severe neonatal hypoxic ischemic encephalopathy. Hypoxia-ischemia alters the electrical impedance characteristics of the brain in neonates; therefore, spectroscopic analysis of the cerebral bioimpedance of the neonate may be useful for the detection of candidate neonates eligible for hypothermia treatment. Currently, in addition to the lack of reference bioimpedance data obtained from healthy neonates, there is no standardized approach established for bioimpedance spectroscopy data analysis. In this work, cerebral bioimpedance measurements (12 h postpartum) in a cross-section of 84 term and near-term healthy neonates were performed at the bedside in the post-natal ward. To characterize the impedance spectra, Cole parameters (R(0), R(∞), f(C) and α) were extracted from the obtained measurements using an analysis process based on a best measurement and highest likelihood selection process. The results obtained in this study complement previously reported work and provide a standardized criterion-based method for data analysis. The availability of electrical bioimpedance spectroscopy reference data and the automatic criterion-based analysis method might support the development of a non-invasive method for prompt selection of neonates eligible for cerebral hypothermic rescue therapy.
New techniques in air-displacement plethysmography seem to have overcome many of the previous pro... more New techniques in air-displacement plethysmography seem to have overcome many of the previous problems of poor reproducibility and validity. These have made body-density measurements available to a larger range of individuals, including children, elderly and sick patients who often have difficulties in being submerged underwater in hydrodensitometry systems. The BOD POD air-displacement system (BOD POD body composition system; Life Measurement Instruments, Concord, CA, USA) is more precise than hydrodensitometry, is simple and rapid to operate (approximately 1 min measurements) and the results agree closely with those of hydrodensitometry (e.g. f 3.4 % for estimation of body fat). Body line scanners employing the principles of three-dimensional photography are potentially able to measure the surface area and volume of the body and its segments even more rapidly (approximately 10 s), butthe validity of the measurements needs to be established. Advances in i.r. spectroscopy and mathematical modelling for calculating the area under the curve have improved precision for measuring enrichment of 2H20 in studies of water dilution (CV 0.1-0-9 % within the range of 400-1000 pIA) in saliva, plasma and urine. The technique is rapid and compares closely with
Tocotrienols have been reported to improve lipid profiles, reduce atherosclerotic lesions, decrea... more Tocotrienols have been reported to improve lipid profiles, reduce atherosclerotic lesions, decrease blood glucose and glycated haemoglobin concentrations, normalise blood pressure in vivo and inhibit adipogenesis in vitro, yet their role in the metabolic syndrome has not been investigated. In this study, we investigated the effects of palm tocotrienol-rich fraction (TRF) on high carbohydrate, high fat diet-induced metabolic, cardiovascular and liver dysfunction in rats. Rats fed a high carbohydrate, high fat diet for 16 weeks developed abdominal obesity, hypertension, impaired glucose and insulin tolerance with increased ventricular stiffness, lower systolic function and reduced liver function. TRF treatment improved ventricular function, attenuated cardiac stiffness and hypertension, and improved glucose and insulin tolerance, with reduced left ventricular collagen deposition and inflammatory cell infiltration. TRF improved liver structure and function with reduced plasma liver enzymes, inflammatory cell infiltration, fat vacuoles and balloon hepatocytes. TRF reduced plasma free fatty acid and triglyceride concentrations but only omental fat deposition was decreased in the abdomen. These results suggest that tocotrienols protect the heart and liver, and improve plasma glucose and lipid profiles with minimal changes in abdominal obesity in this model of human metabolic syndrome.
BACKGROUND AND AIMS Body composition in childhood is not only a marker of the prevalence of obesi... more BACKGROUND AND AIMS Body composition in childhood is not only a marker of the prevalence of obesity, but it can also be used to assess associated metabolic complications. Bioelectrical impedance analysis (BIA) shows promise as an easy to use, rapid, and non-invasive tool to evaluate body composition. The objectives of this study were to: (a) develop BIA prediction equations to estimate total body water (TBW) and fat-free mass (FFM) in European children and early adolescents and to validate the analysis with the deuterium dilution as the reference technique and (b) compare our results with previously published paediatric BIA equations. METHODS The cohort included 266 healthy children and adolescents between 7 and 14 years of age, 46% girls, in five European countries: Bosnia and Herzegovina, Latvia, Montenegro, North Macedonia, and Portugal. TBW and FFM were the target variables in the developed regression models. For model development, the dataset was randomly split into training and test sets, in 70:30 ratio, respectively. Model tuning was performed with 10-fold cross-validation that confirmed the unbiased estimate of its performance. The final regression models were retrained on the whole dataset. RESULTS Cross-validated regression models were developed using resistance index, weight, and sex as the optimal predictors. The new prediction equations explained 87% variability in both TBW and FFM. Limits of agreement between BIA and reference values, were within ±17% of the mean, (-3.4, 3.7) and (-4.5, 4.8) kg for TBW and FFM, respectively. BIA FFM and TBW estimates were within one standard deviation for approximately 83% of the children. BIA prediction equations underestimated TBW and FFM by 0.2 kg and 0.1 kg respectively with no proportional bias and comparable accuracy among different BMI-for-age subgroups. Comparison with predictive equations from published studies revealed varying discrepancy rates with the deuterium dilution measurements, with only two being equivalent to the equations developed in this study. CONCLUSIONS The small difference between deuterium dilution and BIA measurements validated by Bland-Altman analysis, supports the application of BIA for epidemiological studies in European children using the developed equations.
Background: Bioimpedance spectroscopy (BIS) measurements of breast lymphedema poses practical and... more Background: Bioimpedance spectroscopy (BIS) measurements of breast lymphedema poses practical and technical challenges, in particular the determination of the resistance at zero frequency (R0), the index of change in breast lymph content. Conventionally, R0 is calculated from data analysis by using a procedure eponymously known as Cole modeling, a method that is error-prone in the breast. The aim of this study was to evaluate polynomial curve fitting as an alternative analytic procedure. Methods and Results: A sub-set of breast BIS measurements from 41 women with self-ascribed breast lymphedema obtained as part of the Breast Edema Exercise Trial (BEET) were analyzed by both the Cole and polynomial methods. BIS files for all subjects were able to be analyzed by using the polynomial method but only 73% and 88% of data files were analyzed for the affected and unaffected breasts, respectively, by using the Cole method. For those files that were capable of being analyzed by both methods, R0 values were highly correlated (r = 0.99) but with a small (1.6%) although statistically significant difference (paired t test, p < 0.001) between methods. Conclusions: Analysis of BIS data using polynomial curve fitting is an acceptable and robust alternative to Cole modeling, particularly where impedance measurements are susceptible to technical sources of error of measurement. The small magnitude of difference observed between methods is unlikely to lead to misclassification of patients with lymphedema based on BIS assessment.
To determine the relationship between physical methods of measuring lymphedema and self-reported ... more To determine the relationship between physical methods of measuring lymphedema and self-reported swelling, their reliability, and standard error of measurement. Lymphedema in each arm of women with (n = 33) and without (n = 18) unilateral arm lymphedema, secondary to breast cancer was measured by self-report, bioimpedance spectroscopy (BIS), perometer, and the truncated cone method. The physical measurement tools were highly reliable (ICC((2,1)): 0.94 to 1.00) with high concordance (r(c): 0.89 to 0.99). Self-report correlated moderately with physical measurements (r = 0.65 to 0.71) and was moderately reliable (ICC((2,1)): 0.70). Lymphedema assessment methods are concordant and reliable but not interchangeable.
Objectives To evaluate agreement between a reference method (doubly labelled water, DLW) of total... more Objectives To evaluate agreement between a reference method (doubly labelled water, DLW) of total energy expenditure (TEE) and published equations for estimating energy requirements in acute spinal cord injury (SCI). Setting Victoria, Australia Methods Twenty participants (18 male) within 8 weeks of traumatic SCI completed DLW, anthropometric and dietary intake assessments. Energy requirements were predicted using Harris-Benedict, Schofield, Henry, Nelson, Buchholz and Chun equations, multiplied by a combined activity and stress factor of 1.3, and the ratio method (kJ/kg body weight). Fatfree mass (FFM) and fat mass (FM) were calculated from TBW-derived DLW and from bioelectrical impedance spectroscopy (BIS). Results Median time since injury was 41 days. Median TEE was 9.1 MJ. Fair agreement was found between TEE and predicted energy requirements for the Chun (r c = 0.39), the Harris-Benedict equation (r c = 0.30), the ratio method (r c = 0.23) and the Buchholz (r c = 0.31) and Nelson equations (r c = 0.35), which incorporate measures of FFM and/or FM. Other equations showed weak concordance with DLW. When two hypermetabolic patients were removed, agreement between TEE and predicted energy requirements using the Buchholz equation increased to substantial (r c = 0.72) and using the Nelson (r c = 0.53) and Chun equations (r c = 0.53) increased to moderate. The Buchholz equation had the smallest limits of agreement (-2.4-2.3 MJ/d). Conclusion The population-specific Buchholz equation that incorporates FFM, predicted from either BIS or DLW, demonstrated the best agreement in patients with acute SCI.
Practice changing standardization of lower extremity lymphedema quantitative measurements with in... more Practice changing standardization of lower extremity lymphedema quantitative measurements with integrated patient reported outcomes will likely refine and redefine the optimal risk-reduction strategies to diminish the devastating limb-related dysfunction and morbidity associated with treatment of gynecologic cancers. The National Cancer Institute brought together a diverse group of cancer treatment, therapy and patient reported outcomes experts to discuss the current state-ofthe-science in lymphedema evaluation with the potential goal of incorporating new strategies for optimal evaluation of lymphedema in future developing gynecologic clinical trials. The key discussions are outlined in this report.
Human milk (HM) carbohydrates may affect infant appetite regulation, breastfeeding patterns, and ... more Human milk (HM) carbohydrates may affect infant appetite regulation, breastfeeding patterns, and body composition (BC). We investigated relationships between concentrations/calculated daily intakes (CDI) of HM carbohydrates in first year postpartum and maternal/term infant BC, as well as breastfeeding parameters. BC of dyads (n = 20) was determined at 2, 5, 9, and/or 12 months postpartum using ultrasound skinfolds (infants) and bioelectrical impedance spectroscopy (infants/mothers). Breastfeeding frequency, 24-h milk intake and total carbohydrates (TCH) and lactose were measured to calculate HM oligosaccharides (HMO) concentration and CDI of carbohydrates. Statistical analysis used linear regression/mixed effects models; results were adjusted for multiple comparisons. Higher TCH concentrations were associated with greater infant length, weight, fat-free mass (FFM), and FFM index (FFMI), and decreased fat mass (FM), FM index (FMI), %FM and FM/FFM ratio. Higher HMO concentrations were associated with greater infant FFM and FFMI, and decreased FMI, %FM, and FM/FFM ratio. Higher TCH CDI were associated with greater FM, FMI, %FM, and FM/FFM ratio, and decreased infant FFMI. Higher lactose CDI were associated with greater FM, FMI, %FM, and FM/FFM, ratio and decreased FFMI. Concentrations and intakes of HM carbohydrates differentially influence development of infant BC in the first 12 months postpartum, and may potentially influence risk of later obesity via modulation of BC.
Journal of Gastroenterology and Hepatology, Sep 1, 2018
Introduction: Hepatocellular carcinoma (HCC) is now the second leading cause of cancer mortality ... more Introduction: Hepatocellular carcinoma (HCC) is now the second leading cause of cancer mortality worldwide. It is most commonly diagnosed in individuals with established liver cirrhosis related to chronic hepatitis B virus infection (CHB), chronic hepatitis C virus infection (CHC), alcohol, and, increasingly, non-alcoholic fatty liver disease (NAFLD) or nonalcoholic steatohepatitis (NASH). However, the incidence of HCC is also rising in patients without preexisting cirrhosis, notably associated with NAFLD, CHB, type 2 diabetes, or the metabolic syndrome. Aim: We aimed to describe the characteristics of patients diagnosed with HCC at an Australian tertiary hospital over a 40-month period. Methods: The HCC database of the hepatology service was reviewed to establish clinical and sociodemographic characteristics of patients with HCC. Available data included age at diagnosis, mode of diagnosis, anthropometric and biochemical characteristics, etiology and severity of background liver disease, sex, treatments, and survival. Descriptive data are reported as means (standard deviation) or median (interquartile range), and comparisons of patients by sex, HCC etiology, and ethnicity, performed using the independent t test or analysis of variance for normally distributed variables and Mann-Whitney U or Kruskal-Wallis test for non-normally distributed data. Results: One hundred and sixty-one patients were diagnosed with HCC using radiological imaging criteria +/À serum alphafetoprotein levels in most patients. HCC was confirmed histologically from specimens obtained during HCC ablation procedures or the explanted liver at the time of transplantation in 30%. The median age of the patients was 62 years (IQR, 54-76), with the youngest aged 33 years. Most (81.4%) were male, 82.6% were cirrhotic, 32% had diabetes, 35% were obese (47% overweight/obese), and 42% had imaging-diagnosed fatty liver. The most common etiologies were alcohol-related liver disease, CHC, CHB, NAFLD/NASH, or HFE-related hereditary hemochromatosis alone or in combinations. Represented ethnicities included Caucasian (81%), Indigenous Australians/New Zealanders (6%), Chinese (4%), other Asian (4%), and African (2%). Cirrhotic patients with HCC had higher body mass index (BMI) (29.0 [7.1] vs 24.9 [4.6] kg/m 2 ) and INR (1.2 [0.2] vs 1.08 [0.1]) but lower fibrinogen (3.7 [1.3] vs 5.0 [1.4] g/L), platelet count (156 [89] vs 277 [89] × 10 9 ), and serum triglyceride levels (1.3 [0.7] vs 2.1 [1.4] mmol/L) than non-cirrhotic patients (P < 0.05 for all). Caucasian, Indigenous, and other Asian patients with HCC had greater BMI than African, Indian, and Chinese patients with HCC (median, 27.9 [IQR, 23.4-33.5] kg/m 2 vs 22.4 [IQR, 21.7-28.0] kg/m 2 , P = 0.03). Apart from lower high-density lipoprotein cholesterol (HDL-C) in male patients with HCC (1.0 [0.4] vs 1.4 [0.7] mmol/L), there was no other difference in anthropometric and biochemical characteristics between the sexes. There was no difference in serum alphafetoprotein levels based on sex, a cirrhosis diagnosis, or ethnicity in the HCC patients (P > 0.05). Excessive alcohol intake was associated with a younger age at diagnosis of HCC regardless of other hepatic comorbidities (60 [8] vs 65 [12] years, P = 0.004), particularly if alcohol and CHC were comorbid factors (56 [6] vs 65 [10] years, P < 0.001). By contrast, patients with NASH or metabolic syndrome-associated HCC were significantly older than patients with other HCC etiologies (71 [8] vs 60 [9] years, P < 0.001). Conclusions: Patients with HCC were predominantly Caucasian and had underlying cirrhosis. Caucasian patients, Indigenous patients from Australia or New Zealand, and non-Chinese, non-Indian patients with HCC were more likely to be overweight or obese than other HCC patients. Excessive alcohol consumption was associated with younger age at development of HCC, while NASH-or metabolic syndrome-associated HCC was associated with a diagnosis of HCC in older age.
D-optimal designs for nonlinear fixed and mixed effects models are explored, and the theory is ap... more D-optimal designs for nonlinear fixed and mixed effects models are explored, and the theory is applied to the measurement and analysis of bioelectrical impedance. Bioimpedance is known to vary more at extreme frequencies than others. D-optimal designs that account for this variation, and also possible mis-specification of initial parameter estimates, are considered in an attempt to find designs that will provide good parameter estimates in practice.
Hypothermia has been proven as an effective rescue therapy for infants with moderate or severe ne... more Hypothermia has been proven as an effective rescue therapy for infants with moderate or severe neonatal hypoxic ischemic encephalopathy. Hypoxia-ischemia alters the electrical impedance characteristics of the brain in neonates; therefore, spectroscopic analysis of the cerebral bioimpedance of the neonate may be useful for the detection of candidate neonates eligible for hypothermia treatment. Currently, in addition to the lack of reference bioimpedance data obtained from healthy neonates, there is no standardized approach established for bioimpedance spectroscopy data analysis. In this work, cerebral bioimpedance measurements (12 h postpartum) in a cross-section of 84 term and near-term healthy neonates were performed at the bedside in the post-natal ward. To characterize the impedance spectra, Cole parameters (R(0), R(∞), f(C) and α) were extracted from the obtained measurements using an analysis process based on a best measurement and highest likelihood selection process. The results obtained in this study complement previously reported work and provide a standardized criterion-based method for data analysis. The availability of electrical bioimpedance spectroscopy reference data and the automatic criterion-based analysis method might support the development of a non-invasive method for prompt selection of neonates eligible for cerebral hypothermic rescue therapy.
New techniques in air-displacement plethysmography seem to have overcome many of the previous pro... more New techniques in air-displacement plethysmography seem to have overcome many of the previous problems of poor reproducibility and validity. These have made body-density measurements available to a larger range of individuals, including children, elderly and sick patients who often have difficulties in being submerged underwater in hydrodensitometry systems. The BOD POD air-displacement system (BOD POD body composition system; Life Measurement Instruments, Concord, CA, USA) is more precise than hydrodensitometry, is simple and rapid to operate (approximately 1 min measurements) and the results agree closely with those of hydrodensitometry (e.g. f 3.4 % for estimation of body fat). Body line scanners employing the principles of three-dimensional photography are potentially able to measure the surface area and volume of the body and its segments even more rapidly (approximately 10 s), butthe validity of the measurements needs to be established. Advances in i.r. spectroscopy and mathematical modelling for calculating the area under the curve have improved precision for measuring enrichment of 2H20 in studies of water dilution (CV 0.1-0-9 % within the range of 400-1000 pIA) in saliva, plasma and urine. The technique is rapid and compares closely with
Tocotrienols have been reported to improve lipid profiles, reduce atherosclerotic lesions, decrea... more Tocotrienols have been reported to improve lipid profiles, reduce atherosclerotic lesions, decrease blood glucose and glycated haemoglobin concentrations, normalise blood pressure in vivo and inhibit adipogenesis in vitro, yet their role in the metabolic syndrome has not been investigated. In this study, we investigated the effects of palm tocotrienol-rich fraction (TRF) on high carbohydrate, high fat diet-induced metabolic, cardiovascular and liver dysfunction in rats. Rats fed a high carbohydrate, high fat diet for 16 weeks developed abdominal obesity, hypertension, impaired glucose and insulin tolerance with increased ventricular stiffness, lower systolic function and reduced liver function. TRF treatment improved ventricular function, attenuated cardiac stiffness and hypertension, and improved glucose and insulin tolerance, with reduced left ventricular collagen deposition and inflammatory cell infiltration. TRF improved liver structure and function with reduced plasma liver enzymes, inflammatory cell infiltration, fat vacuoles and balloon hepatocytes. TRF reduced plasma free fatty acid and triglyceride concentrations but only omental fat deposition was decreased in the abdomen. These results suggest that tocotrienols protect the heart and liver, and improve plasma glucose and lipid profiles with minimal changes in abdominal obesity in this model of human metabolic syndrome.
BACKGROUND AND AIMS Body composition in childhood is not only a marker of the prevalence of obesi... more BACKGROUND AND AIMS Body composition in childhood is not only a marker of the prevalence of obesity, but it can also be used to assess associated metabolic complications. Bioelectrical impedance analysis (BIA) shows promise as an easy to use, rapid, and non-invasive tool to evaluate body composition. The objectives of this study were to: (a) develop BIA prediction equations to estimate total body water (TBW) and fat-free mass (FFM) in European children and early adolescents and to validate the analysis with the deuterium dilution as the reference technique and (b) compare our results with previously published paediatric BIA equations. METHODS The cohort included 266 healthy children and adolescents between 7 and 14 years of age, 46% girls, in five European countries: Bosnia and Herzegovina, Latvia, Montenegro, North Macedonia, and Portugal. TBW and FFM were the target variables in the developed regression models. For model development, the dataset was randomly split into training and test sets, in 70:30 ratio, respectively. Model tuning was performed with 10-fold cross-validation that confirmed the unbiased estimate of its performance. The final regression models were retrained on the whole dataset. RESULTS Cross-validated regression models were developed using resistance index, weight, and sex as the optimal predictors. The new prediction equations explained 87% variability in both TBW and FFM. Limits of agreement between BIA and reference values, were within ±17% of the mean, (-3.4, 3.7) and (-4.5, 4.8) kg for TBW and FFM, respectively. BIA FFM and TBW estimates were within one standard deviation for approximately 83% of the children. BIA prediction equations underestimated TBW and FFM by 0.2 kg and 0.1 kg respectively with no proportional bias and comparable accuracy among different BMI-for-age subgroups. Comparison with predictive equations from published studies revealed varying discrepancy rates with the deuterium dilution measurements, with only two being equivalent to the equations developed in this study. CONCLUSIONS The small difference between deuterium dilution and BIA measurements validated by Bland-Altman analysis, supports the application of BIA for epidemiological studies in European children using the developed equations.
Background: Bioimpedance spectroscopy (BIS) measurements of breast lymphedema poses practical and... more Background: Bioimpedance spectroscopy (BIS) measurements of breast lymphedema poses practical and technical challenges, in particular the determination of the resistance at zero frequency (R0), the index of change in breast lymph content. Conventionally, R0 is calculated from data analysis by using a procedure eponymously known as Cole modeling, a method that is error-prone in the breast. The aim of this study was to evaluate polynomial curve fitting as an alternative analytic procedure. Methods and Results: A sub-set of breast BIS measurements from 41 women with self-ascribed breast lymphedema obtained as part of the Breast Edema Exercise Trial (BEET) were analyzed by both the Cole and polynomial methods. BIS files for all subjects were able to be analyzed by using the polynomial method but only 73% and 88% of data files were analyzed for the affected and unaffected breasts, respectively, by using the Cole method. For those files that were capable of being analyzed by both methods, R0 values were highly correlated (r = 0.99) but with a small (1.6%) although statistically significant difference (paired t test, p < 0.001) between methods. Conclusions: Analysis of BIS data using polynomial curve fitting is an acceptable and robust alternative to Cole modeling, particularly where impedance measurements are susceptible to technical sources of error of measurement. The small magnitude of difference observed between methods is unlikely to lead to misclassification of patients with lymphedema based on BIS assessment.
To determine the relationship between physical methods of measuring lymphedema and self-reported ... more To determine the relationship between physical methods of measuring lymphedema and self-reported swelling, their reliability, and standard error of measurement. Lymphedema in each arm of women with (n = 33) and without (n = 18) unilateral arm lymphedema, secondary to breast cancer was measured by self-report, bioimpedance spectroscopy (BIS), perometer, and the truncated cone method. The physical measurement tools were highly reliable (ICC((2,1)): 0.94 to 1.00) with high concordance (r(c): 0.89 to 0.99). Self-report correlated moderately with physical measurements (r = 0.65 to 0.71) and was moderately reliable (ICC((2,1)): 0.70). Lymphedema assessment methods are concordant and reliable but not interchangeable.
Objectives To evaluate agreement between a reference method (doubly labelled water, DLW) of total... more Objectives To evaluate agreement between a reference method (doubly labelled water, DLW) of total energy expenditure (TEE) and published equations for estimating energy requirements in acute spinal cord injury (SCI). Setting Victoria, Australia Methods Twenty participants (18 male) within 8 weeks of traumatic SCI completed DLW, anthropometric and dietary intake assessments. Energy requirements were predicted using Harris-Benedict, Schofield, Henry, Nelson, Buchholz and Chun equations, multiplied by a combined activity and stress factor of 1.3, and the ratio method (kJ/kg body weight). Fatfree mass (FFM) and fat mass (FM) were calculated from TBW-derived DLW and from bioelectrical impedance spectroscopy (BIS). Results Median time since injury was 41 days. Median TEE was 9.1 MJ. Fair agreement was found between TEE and predicted energy requirements for the Chun (r c = 0.39), the Harris-Benedict equation (r c = 0.30), the ratio method (r c = 0.23) and the Buchholz (r c = 0.31) and Nelson equations (r c = 0.35), which incorporate measures of FFM and/or FM. Other equations showed weak concordance with DLW. When two hypermetabolic patients were removed, agreement between TEE and predicted energy requirements using the Buchholz equation increased to substantial (r c = 0.72) and using the Nelson (r c = 0.53) and Chun equations (r c = 0.53) increased to moderate. The Buchholz equation had the smallest limits of agreement (-2.4-2.3 MJ/d). Conclusion The population-specific Buchholz equation that incorporates FFM, predicted from either BIS or DLW, demonstrated the best agreement in patients with acute SCI.
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Papers by Leigh Ward