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Metabolic Variables (metabolic + variable)
Selected AbstractsRelation between C-reactive protein levels and body composition in a multiethnic sample of school children in HawaiiAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 5 2010Daniel E. Brown Objectives: Adipose cells secrete proinflammatory cytokines that stimulate hepatic production of C-reactive protein (CRP). CRP levels are associated with adiposity levels in adults, adolescents, and older children but not in young children (age 2,3). This study examined the relation between CRP, adiposity, and cardiovascular and metabolic variables including blood pressure, glucose, and blood lipids in two young cohorts of children, averaging ,5.5 and 8.5 years, respectively. Methods: Children (N = 125) from eight elementary schools in the multiethnic community of Hilo Hawaii were recruited to fill out questionnaires, undergo anthropometrics and air displacement plethysmography, have resting blood pressure measured, and provide a finger stick blood sample for analysis of CRP, glucose, and blood lipids. Results: There were no significant differences between the cohorts in ethnic make up, household income, or parents' educational attainment. No significant relation was found between CRP and either adiposity or cardiovascular/metabolic variables in the younger cohort. However, significant correlations were found between CRP and adiposity measures and blood pressure in the older cohort. There was no marked difference in association of CRP with BMI versus waist circumference or waist-to-hip ratio. In neither cohort was CRP significantly related to glucose or blood lipids. Conclusions: Both amount of fat mass and time duration for possessing the adipose tissue may be important factors in determining the relation between CRP and both adiposity and blood pressure. Am. J. Hum. Biol. 22:675,679, 2010. © 2010 Wiley-Liss, Inc. [source] Effects of caudal hindbrain lactate infusion on insulin-induced hypoglycemia and neuronal substrate transporter glucokinase and sulfonylurea receptor-1 gene expression in the ovariectomized female rat dorsal vagal complex: Impact of estradiolJOURNAL OF NEUROSCIENCE RESEARCH, Issue 3 2008Kamlesh V. Vavaiya Abstract The monocarboxylate, lactate, is produced by astrocytic glycolysis and is trafficked to neurons as a substrate fuel for aerobic respiration. This molecule is a critical monitored metabolic variable in hindbrain detection of cellular energy imbalance, because diminished uptake and/or oxidative catabolism of lactate in this part of the brain activates neural mechanisms that increase systemic glucose availability. Lactate-sensitive chemosensory neurons occur in the hindbrain dorsal vagal complex (DVC). Estradiol (E) enhances expression of the neuronal monocarboxylate transporter MCT2 in the DVC during insulin-induced hypoglycemia (IIH), evidence that this hormone may promote local lactate utilization during systemic glucose shortages. We investigated the hypothesis that E regulates basal and IIH-associated patterns of DVC MCT2 and neuronal glucose transporter gene expression and that caudal fourth ventricular (CV4) lactate infusion exerts divergent effects on blood glucose levels and DVC energy transducer gene profiles in hypoglycemic E- vs. oil (O)-implanted ovariectomized (OVX) rats. Insulin-induced decrements in circulating glucose were significantly augmented by lactate, albeit to a greater extent in the presence of E. DVC MCT2, GLUT3, GLUT4, glucokinase (GCK), and sulfonylurea receptor-1 (SUR1) mRNA levels did not differ between saline-injected OVX + E and OVX + O rats. IIH elevated MCT2 and GLUT3 gene profiles in both E- and O-implanted groups, but up-regulation of MCT2 transcripts was reversed by CV4 lactate infusion during hypoglycemia in E- but not O-implanted animals. DVC GLUT4 and GK mRNA were decreased by insulin alone in OVX + O but not OVX + E, but were suppressed by lactate plus insulin treatment in the latter group. Expression of the SUR1 subunit of the energy-dependent potassium channel KATP was significantly decreased by IIH in both E- and O-treated rats and further suppressed in response to lactate delivery during hypoglycemia in OVX + E. These data reveal that E does not control baseline DVC substrate fuel transporter or energy transducer gene profiles or local MCT2, GLUT3, or SUR1 transcriptional responses to IIH but prevents IIH-associated decreases in GLUT4 and GCK mRNA in this brain site. The results also show that, in the presence of E, intensifying effects of CV4 lactate infusion on hypoglycemia are correlated with reversal of IIH enhancement of DVC MCT2 gene expression, augmented IIH inhibition of SUR1 transcripts, and reductions in GLUT4 and GCK mRNA levels relative to baseline. This work implies that IIH may enhance specific neuronal lactate and glucose transport mechanisms in the female rat DVC and that, in the presence of E, caudal hindbrain lactate repletion may normalize neuronal lactate but not glucose internalization by local neurons. The results also suggest that putative IIH-associated reductions in KATP -mediated regulation of membrane voltage in this brain site may be causally related to diminished glucose availability. © 2007 Wiley-Liss, Inc. [source] Relationship of glucose concentrations with PAI-1 and t-PA in subjects with normal glucose toleranceDIABETIC MEDICINE, Issue 8 2006P. E. Heldgaard Abstract Aims To study metabolic risk factors for the development of cardiovascular disease (CVD), including markers of the fibrinolytic system in relation to blood glucose levels in subjects with normal glucose tolerance and fasting blood glucose levels below 5.6 mmol/l. Methods Cross-sectional, community-based study from a primary health-care centre of adult subjects with normal glucose tolerance. Analysis of fasting and 2-h post-load blood glucose concentrations were centralized and related to anthropometric characteristics, metabolic variables, inflammatory markers, and coagulation and fibrinolytic variables. Results Increasing fasting blood glucose concentrations within the normal range in subjects with normal glucose tolerance were associated with increasing age, body mass index, and waist circumference, and with increasing concentrations of metabolic risk factors for development of CVD. After adjustment for gender, age, body mass index (BMI), and fasting insulin, levels of plasmin activator inhibitor (PAI-1) and tissue type plasminogen activator (t-PA) increased significantly with increasing levels of fasting glucose within the normal range (P = 0.012 and P < 0.0001, respectively). Conclusions We found risk factors for CVD, specifically key components of the fibrinolytic system, PAI-1 and t-PA, increased with increasing fasting glucose levels even in subjects with normal glucose tolerance. This observation may help to explain the increased risk of CVD with increasing values of fasting glucose in the normal range. [source] Autoantibodies to the islet cell antigen SOX-13 are associated with duration but not type of diabetesDIABETIC MEDICINE, Issue 3 2003T. M. E. Davis Abstract Aims The autoantigen SOX-13 of the SRY-related high mobility group box is a low-frequency reactant in sera from patients with Type 1 diabetes. We further investigated the potential diagnostic role of anti-SOX-13, and in particular its ability to distinguish Type 1 from Type 2 diabetes, in two large, well-characterized cohorts. Methods SOX-13 autoantibody status was ascertained using a radioimmunoprecipitation assay in (i) a random sample of 546 participants in an Australian community-based study (the Fremantle Diabetes Study; FDS) of whom 119 had Type 1 and 427 Type 2 diabetes, and (ii) a sample of 333 subjects with Type 2 diabetes from the United Kingdom Prospective Diabetes Study (UKPDS) stratified by age, anti-glutamic acid decarboxylase (GAD) and islet cell antibody (ICA) status, and requirement for insulin therapy within 6 years of diagnosis. Results The frequencies of anti-SOX-13 in the FDS subjects were 16.0% and 14.8% for Type 1 and Type 2 patients, respectively, and levels were similar. In the UKPDS subjects, the frequency was 4.5%. In a logistic regression model involving demographic, anthropometric and metabolic variables, only diabetes duration was significantly associated with anti-SOX-13 positivity, especially for duration > 5 years (P < 0.002). When the coexistence of autoantibodies was assessed in the two study samples, there were no significant associations between anti-SOX-13 and ICA, anti-GAD or ICA512/IA-2. Conclusions Whilst the frequency of anti-SOX-13 may be increased in some populations of diabetic patients, this reactivity does not usefully distinguish Type 1 from Type 2 diabetes. However, the association with diabetes duration suggests that anti-SOX-13 may be a non-specific marker of tissue damage associated with chronic hyperglycaemia. Diabet. Med. 20, 198,204 (2003) [source] Are Hormonal Responses to Exercise in Young Men with Down's Syndrome Related to Reduced Endurance Performance?JOURNAL OF NEUROENDOCRINOLOGY, Issue 5 2008V-A. Bricout The aim of the present study was to analyse whether hormonal responses could explain an exercise limitation in Down's syndrome (DS). Fourteen young men with DS (mean age 22.5 ± 0.7 years) and 15 controls (CONT, mean age 22.5 ± 0.3 years) participated in the study. During a treadmill submaximal incremental test, blood samples were collected for determination of hormonal and metabolic variables. Compared to CONT, DS individuals showed lower VO2max (P < 0.05), and lower duration of submaximal incremental exercise (P < 0.001). At rest, DS individuals showed greater catecholamines, insulin and leptin values (P < 0.05), but lower testosteronemia and cortisolemia (P < 0.05), compared to CONT. During submaximal incremental tests, catecholamines and cortisol were not increased, whereas the insulin concentration of DS individuals was significantly higher (P < 0.01) compared to CONT. Glycaemia increased significantly at the end of submaximal incremental test for CONT but not for DS individuals (P < 0.01). Maximal fat oxidation was lower (P < 0.01), whereas non-esterified fatty acids concentrations rose significantly during submaximal exercise in DS individuals. These results indicate an altered hormonal response to exercise in DS individuals. This endocrine profile at rest and during exercise may limit endurance performance in DS individuals. [source] Reproducibility assessment of metabolic variables characterizing muscle energetics in Vivo: A 31P-MRS studyMAGNETIC RESONANCE IN MEDICINE, Issue 4 2009Gwenael Layec Abstract The purpose of the present study was to assess the reliability of metabolic parameters measured using 31P magnetic resonance spectroscopy (31P MRS) during two standardized rest-exercise-recovery protocols. Twelve healthy subjects performed the standardized protocols at two different intensities; i.e., a moderate intensity (MOD) repeated over a two-month period and heavy intensity (HEAVY) repeated over a year's time. Test-retest reliability was analyzed using coefficient of variation (CV), limits of agreement (LOA), and intraclass correlation coefficients (ICC). During exercise and recovery periods, most of the metabolic parameters exhibited a good reliability. The CVs of individual concentration of phosphocreatine ([PCr]), concentration of adenosine diphosphate ([ADP]), and pH values recorded at end of the HEAVY exercise were lower than 15%. The CV calculated for the rate of PCr resynthesis and the maximal oxidative capacity were less than 13% during the HEAVY protocol. Inferred parameters such as oxidative and total adenosine triphosphate (ATP) production rates exhibited a good reliability (ICC , 0.7; CV < 15% during the HEAVY protocol). Our results demonstrated that measurement error using 31P-MRS during a standardized exercise was low and that biological variability accounted for the vast majority of the measurement variability. In addition, the corresponding metabolic measurements can reliably be used for longitudinal studies performed even over a long period of time. Magn Reson Med, 2009. © 2009 Wiley-Liss, Inc. [source] Relation between C-reactive protein levels and body composition in a multiethnic sample of school children in HawaiiAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 5 2010Daniel E. Brown Objectives: Adipose cells secrete proinflammatory cytokines that stimulate hepatic production of C-reactive protein (CRP). CRP levels are associated with adiposity levels in adults, adolescents, and older children but not in young children (age 2,3). This study examined the relation between CRP, adiposity, and cardiovascular and metabolic variables including blood pressure, glucose, and blood lipids in two young cohorts of children, averaging ,5.5 and 8.5 years, respectively. Methods: Children (N = 125) from eight elementary schools in the multiethnic community of Hilo Hawaii were recruited to fill out questionnaires, undergo anthropometrics and air displacement plethysmography, have resting blood pressure measured, and provide a finger stick blood sample for analysis of CRP, glucose, and blood lipids. Results: There were no significant differences between the cohorts in ethnic make up, household income, or parents' educational attainment. No significant relation was found between CRP and either adiposity or cardiovascular/metabolic variables in the younger cohort. However, significant correlations were found between CRP and adiposity measures and blood pressure in the older cohort. There was no marked difference in association of CRP with BMI versus waist circumference or waist-to-hip ratio. In neither cohort was CRP significantly related to glucose or blood lipids. Conclusions: Both amount of fat mass and time duration for possessing the adipose tissue may be important factors in determining the relation between CRP and both adiposity and blood pressure. Am. J. Hum. Biol. 22:675,679, 2010. © 2010 Wiley-Liss, Inc. [source] Variation in the incidence of and risk factors for the development of nephrolithiasis after radical or partial nephrectomyBJU INTERNATIONAL, Issue 8 2010Aditya Bagrodia Study Type , Prevalence (retrospective cohort) Level of Evidence 2b OBJECTIVE To examine incidence of and risk factors for the development of nephrolithiasis in patients treated with radical nephrectomy (RN) or partial nephrectomy (nephron-sparing surgery, NSS). PATIENTS AND METHODS The study comprised a single-centre review of 749 patients treated with RN or NSS from August 1987 to June 2006. Demographics, medical and stone history, metabolic variables and postoperative stone events were recorded. Data were analysed within subgroups based on treatment (RN vs NSS). Multivariate analysis was used to identify risk factors for postoperative stone formation. RESULTS In all, 499 patients had RN and 250 had NSS (mean age 57.9 years; mean follow-up 6.3 years). There were no significant differences in their demographic factors, but tumours were significantly larger in RN (P < 0.001). There was no significant difference in preoperative urinary pH < 6.0 or stone history. Significantly fewer patients after NSS than RN formed calculi (NSS 1.6% vs RN 8.4%, P < 0.001), developed hypobicarbonataemia (NSS 7.2% vs RN 12.8%, P= 0.020), and a urinary pH of <6.0 (NSS 11.2% vs RN 19.4%, P= 0.004). Multivariate analysis showed that RN (odds ratio 18.18), postoperative urinary pH < 6 (15.63), previous stone disease (13.7), age <60 years (7.33, all P < 0.001), body mass index ,30 kg/m2 (3.26, P= 0.033), male gender (2.67, P= 0.039), and hypobicarbonataemia (2.46, P= 0.034) were significantly associated with the development of postoperative calculi. CONCLUSIONS Patients undergoing RN have a significantly higher incidence of postoperative nephrolithiasis than a well-matched cohort undergoing NSS. In addition to RN, male sex, urinary pH < 6.0, hypobicarbonataemia, history of stone disease, obesity, and age <60 years were significantly associated with postoperative stone formation. [source] Evaluation of a severity score to predict the prognosis of Fournier's gangreneBJU INTERNATIONAL, Issue 3 2010Saturnino Luján Marco Study Type , Prognosis (case series) Level of Evidence 4 OBJECTIVE To determine the validity of a Fournier's gangrene severity index (FGSI), developed to assign a numerical score describing the severity of FG, and evaluate factors in the survival of patients with FG. PATIENTS AND METHODS We retrospectively reviewed 51 patients diagnosed with FG between 1994 and 2006. Data were collected on their medical history, which included vital signs (temperature, heart and respiratory rates) and metabolic variables (sodium, potassium, creatinine, bicarbonate levels, haematocrit, and white blood cell count). We computed a score relating to the severity of the disease at the time, and compared it to other features according to whether the patient survived or died. The different prognostic factors were assessed by univariate analysis with the Mann,Whitney U and Kendall A-B tests. RESULTS Of the evaluated 51 inpatients, eight died (16%) and 43 survived (84%). The median (range) age was 63 (17,85) years and the median time from the onset of the symptoms until the admission to the emergency room was 7.8 (1,60) days. The mean hospital stay was 33 (2,90) days and 17 patients were admitted to the intensive-care unit for a mean of 4.5 days. There was no statistically significant difference between the groups. Body surfaces involved were the scrotum in five patients (10%), the penis and scrotum in 11 (22%), the scrotum and perineum in 30 (59%) and the abdominal wall in five (10%). There was no statistically significant difference in the distribution in those who survived or died (P = 0.131). The median age of 60 (17,81) years in the survivors was significantly lower than that of 73.5 (50,85) years in those who died (P = 0.02). There was no significant difference (P = 0.06) between the number of repeated debridements in the survivors (3.23) and those who died (5.25). The mean (range) FGSI score for survivors was 6.7 (0,14), vs 8.7 (6,13) for those who died (P = 0.12). The only laboratory variables associated with death were serum bicarbonate (P = 0.04) and serum sodium (P = 0.02) levels. CONCLUSIONS FG is an unpredictable disease process with wide variability in its presentation. In our experience, the FGSI gives no indication of the likelihood of survival, but the risk factors for predicting the severity of FG seem to be greater in older patients and those with high sodium and low bicarbonate levels. [source] Combined blockade of endothelin-1 and thromboxane A2 receptors against postischaemic contractile dysfunction in rat heartsBRITISH JOURNAL OF PHARMACOLOGY, Issue 1 2001Pius S Hornstein Endothelin-1 (ET-1) may play a role in myocardial ischaemia/reperfusion injury because both the release and vasoconstrictor effect of ET-1 are increased after ischaemia. Since the increased vasoconstrictor effect of ET-1 can be mediated by ET-1-induced release of thromboxane A2 (TXA2), the aim of this study was to test whether combined blockade of ET and TXA2 receptors protects the coronary flow, contractile performance, and cardiac energy metabolism during ischaemia and reperfusion. Bosentan (antagonist for ETA and ETB receptors, 1 ,M based on concentration-response curves of ET-1), SQ 30,741 (antagonist of TXA2 receptors, 0.1 ,M), or the combination thereof was administered to isolated perfused rat hearts undergoing 15 min of global ischaemia and 60 min of reperfusion. Neither bosentan or SQ 30,741 alone, nor the combination thereof, improved the incomplete postischaemic recovery of coronary flow, left ventricular developed pressure, phosphocreatine, or ATP. However, they attenuated ischaemia-induced acidosis but this did not translate into a measurable effect on haemodynamic or metabolic variables. Thus, combined blockade of ET and TXA2 receptors does not protect the coronary flow, contractile performance, and cardiac energy metabolism during ischaemia and reperfusion in isolated perfused rat hearts. This finding suggests that neither ET-1 nor ET-1-induced release of TXA2 play a major role in the postischaemic recovery of the cardiac contractile function and energy metabolism. British Journal of Pharmacology (2001) 132, 234,240; doi:10.1038/sj.bjp.0703773 [source] ORIGINAL ARTICLE: Metabolic outcome of GH treatment in prepubertal short children with and without classical GH deficiencyCLINICAL ENDOCRINOLOGY, Issue 3 2010Ralph Decker Summary Context, Few studies have evaluated the metabolic outcomes of growth hormone (GH) treatment in idiopathic short stature (ISS). Moreover, children with ISS appear to need higher GH doses than children with GH deficiency (GHD) to achieve the same amount of growth and may therefore be at increased risk of adverse events during treatment. The individualized approach using prediction models for estimation of GH responsiveness, on the other hand, has the advantage of narrowing the range of growth response, avoiding too low or high GH doses. Design, Short prepubertal children with either isolated GHD (39) or ISS (89) participated in a 2-year randomized trial of either individualized GH treatment with six different GH doses (range, 17,100 ,g/kg/day) or a standard dose (43 ,g/kg/day). Objective, To evaluate if individualized GH treatment reduced the variance of the metabolic measures as shown for growth response and to compare changes in metabolic variables in children with ISS and GHD. Hypothesis, Individualized GH dose reduces the range of metabolic outcomes, and metabolic outcomes are similar in children with ISS and GHD. Results, We observed a narrower variation for fasting insulin (,34·2%) and for homoeostasis model assessment (HOMA) (,38·9%) after 2 years of individualized GH treatment in comparison with standard GH dose treatment. Similar metabolic changes were seen in ISS and GHD. Delta (,) height SDS correlated with ,insulin-like growth factor I (IGF-I), ,leptin and ,body composition. Principal component analysis identified an anabolic and a lipolytic component. Anabolic variables [,lean body mass (LBM) SDS and ,IGF-I SDS] clustered together and correlated strongly with ,height SDS and GH dose, whereas lipolytic variables [,fat mass (FM) SDS and ,leptin] were clustered separately from anabolic variables. Regression analysis showed GH dose dependency in ISS, and to a lesser degree in GHD, for ,LBM SDS and ,height SDS, but not for changes in FM. Conclusions, Individualized GH dosing during catch-up growth reduces the variance in insulin and HOMA and results in equal metabolic responses irrespective of the diagnosis of GHD or ISS. [source] | |||||||||||||