ND Subjects Research Articles

Impaired Diurnal Pattern of Meal Tolerance and Insulin Sensitivity in Type 2 Diabetes: Implications for Therapy.

To assess the diurnal patterns of postprandial glucose tolerance and insulin sensitivity, 19 subjects with type 2 diabetes (8 women; 60 ± 11 years; BMI 32 ± 5 kg/m2) and 19 anthropometrically matched subjects with no diabetes (ND; 11 women; 53 ± 12 years; BMI 29 ± 5 kg/m2) were studied during breakfast (B), lunch (L), and dinner (D) with identical mixed meals (75 g carbohydrates) on 3 consecutive days in a randomized Latin square design. Three stable isotopes of glucose were ustilized to estimate meal fluxes, and mathematical models were used in estimating indices of insulin action and β-cell function. Postmeal glucose excursions were higher at D versus B and at D versus L in type 2 diabetes (P < 0.05), while in ND they were higher at D versus B (P = 0.025) and at L versus B (P = 0.04). The insulin area under the curve was highest at B compared with L and D in type 2 diabetes, while no differences were observed in ND. Disposition index (DI) was higher at B than at L (P < 0.01) and at D (P < 0.001) in ND subjects, whereas DI was low with unchanging pattern across B-L-D in individuals with type 2 diabetes. Furthermore, between-meal differences in β-cell responsivity to glucose (F) and insulin sensitivity (SI) were concurrent with changes in the DI within groups. Fasting and postmeal glucose, insulin, and C-peptide concentrations, along with estimates of endogenous glucose production (EGP), Rd, SI, F, hepatic extraction of insulin, insulin secretion rate, extracted insulin, and DI, were altered in type 2 diabetes compared with ND (P < 0.011 for all). The data show a diurnal pattern of postprandial glucose tolerance in overweight otherwise glucose-tolerant ND individuals that differs from overweight individuals with type 2 diabetes. The results not only provide valuable insight into management strategies for better glycemic control in people with type 2 diabetes, but also improved understanding of daytime glucose metabolism in overweight individuals without impaired glucose tolerance or overt diabetes.

Increased frequency of \u03b2 cells with abnormal NKX6.1 expression in type 2 diabetes but not in subjects with higher risk for type 2 diabetes

BackgroundNKX6.1 is a transcription factor for insulin, as well as a marker for β cell maturity. Abnormal NKX6.1 expression in β cells, such as translocation from the nucleus to cytoplasm or lost expression, has been shown as a marker for β cell dedifferentiation.MethodsWe obtained pancreatic sections from organ donors and immunofluorescence staining with NKX6.1 and insulin was performed to characterize NKX6.1 expression in subjects with or without type 2 diabetes mellitus (T2DM).ResultsOur results showed that cells with insulin expression but no nucleic NKX6.1 expression (NKX6.1Nuc-Ins+), and cells with cytoplasmic NKX6.1 expression but no insulin expression (NKX6.1cytIns−) were significantly increased in T2DM subjects and positively correlated with glycated hemoglobin (HbA1c), indicating the elevated β cell dedifferentiation with NKX6.1 inactivation in T2DM. To investigate whether β cell dedifferentiation has initiated in subjects with higher risks for T2DM, we next analyzed the association between β-cell dedifferentiation level in ND subjects with different ages, body mass index, and HbA1c. The results showed the absolute number and percentage of dedifferentiated β cells with NKX6.1 inactivation did not significantly change in subjects with advanced aging, obesity, or modest hyperglycemia, indicating that the β cell dedifferentiation might mainly occur after T2DM was diagnosed.ConclusionOur results suggested that NKX6.1 expression in β cells was changed in type 2 diabetic subjects, evidenced by significantly increased NKX6.1Nuc-Ins+ and NKX6.1cytIns− cells. This abnormality did not occur more frequently in subjects with a higher risk for T2DM, suggesting that β cell dedifferentiation might be secondary to the pathological changes in T2DM.

Identification of Subclinical Lung Involvement in ACPA-Positive Subjects through Functional Assessment and Serum Biomarkers.

Lung involvement is related to the natural history of anti-citrullinated proteins antibodies (ACPA)-positive rheumatoid arthritis (RA), both during the pathogenesis of the disease and as a site of disease-related injury. Increasing evidence suggests that there is a subclinical, early lung involvement during the course of the disease, even before the onset of articular manifestations, which can potentially progress to a symptomatic interstitial lung disease. To date, reliable, non-invasive markers of subclinical lung involvement are still lacking in clinical practice. The aim of this study is to evaluate the diagnostic potential of functional assessment and serum biomarkers in the identification of subclinical lung involvement in ACPA-positive subjects. Fifty ACPA-positive subjects with or without confirmed diagnosis of RA (2010 ARC-EULAR criteria) were consecutively enrolled. Each subject underwent clinical evaluation, pulmonary function testing (PFT) with assessment of diffusion lung capacity for carbon monoxide (DLCO), cardiopulmonary exercise testing (CPET), surfactant protein D (SPD) serum levels dosage and high-resolution computed tomography (HRCT) of the chest. The cohort was composed of 21 ACPA-positive subjects without arthritis (ND), 10 early (disease duration < 6 months, treatment-naïve) RA (ERA) and 17 long-standing (disease duration < 36 months, on treatment) RA (LSRA). LSRA patients had a significantly higher frequency of overall HRCT abnormalities compared to the other groups (p = 0.001). SPD serum levels were significantly higher in ACPA-positive subjects compared with healthy controls (158.5 ± 132.3 ng/mL vs 61.27 ± 34.11 ng/mL; p < 0.0001) and showed an increasing trend from ND subjects to LSRD patients (p = 0.004). Patients with HRCT abnormalities showed significantly lower values of DLCO (74.19 ± 13.2% pred. vs 131.7 ± 93% pred.; p = 0.009), evidence of ventilatory inefficiency at CPET and significantly higher SPD serum levels compared with subjects with no HRCT abnormalities (213.5 ± 157.2 ng/mL vs 117.7 ± 157.3 ng/mL; p = 0.018). Abnormal CPET responses and higher SPD levels were also associated with specific radiological findings. Impaired DLCO and increased SPD serum levels were independently associated with the presence of HRCT abnormalities. Subclinical lung abnormalities occur early in RA-associated autoimmunity. The presence of subclinical HRCT abnormalities is associated with several functional abnormalities and increased SPD serum levels of SPD. Functional evaluation through PFT and CPET, together with SPD assessment, may have a diagnostic potential in ACPA-positive subjects, contributing to the identification of those patients to be referred to HRCT scan.

691-P: Exercise Effect on Endogenous Glucose Production in Type 1 Diabetes: A Modeling Analysis

Quantifying the exercise effect (EE) on glucose turnover is fundamental for type 1 diabetes (T1D) management. We recently proposed a model describing EE on insulin-dependent and -independent glucose utilization in subjects with and without T1D (ND). However, to date, a model of EE on endogenous glucose production (EGP) is still lacking. To do so, we analysed existing data on 6 T1D (age 29±3 yrs, BMI 28.3±2.0 kg/m2, VO2 max 28.7±2.9 ml/kg/min, mean±SE) and 6 ND (age=28.2±4.2 yr, BMI=23.6 ±1.0 kg/m2, VO2 max 36.6±2.9 ml/kg/min) subjects studied with a glucose clamp, during, before and after a 60 min aerobic exercise session at 65% VO2max on three visits: euglycemia-low insulin (V1); euglycemia-high insulin (V2) and hyperglycemia-low insulin (V3) in random order. EGP was measured with the isotope dilution technique using [6,6-2H2]glucose. A battery of models was tested against data to assess if EE on EGP is mediated by insulin, glucose or both. The best model (Fig 1) provided a good description of the data in both groups. Results show that EE on EGP is delayed and insulin mediated. Further studies are needed to validate the model in real life conditions thus making it usable for optimization of insulin therapy. Disclosure D. Romeres: None. M. Schiavon: None. R. Visentin: None. A. Basu: Consultant; Spouse/Partner; GENFIT. Research Support; Spouse/Partner; AstraZeneca. C. Cobelli: None. R. Basu: Consultant; Self; GENFIT. Research Support; Self; AstraZeneca. C. Dalla Man: Research Support; Self; Sanofi-Aventis Deutschland GmbH. Funding Italian Ministry of Education (232/2016); National Institute of Diabetes and Digestive and Kidney Diseases (DK029953 to R.B.), (DK085516 to A.B.)

Exercise‐enriched extracellular vesicles benefit brain health by decreasing protein aggregation

Aerobic exercise results in improved brain health during both healthy aging and dementia. However, the precise biological mechanisms that drive exercise‐induced benefits for brain health remain unknown. One possible mechanism by which exercise may benefit the brain is by facilitating the delivery of molecular mediators within extracellular vesicles (EVs; exosomes and microvesicles). EVs are bilayer‐phospholipid enclosed vesicles that carry protein and microRNA cargo and are released into the blood from many organs and cells. EVs have been shown to regulate nerve regeneration, synaptic function and behavior. Importantly, when directly injected into rodent brains, EVs can effectively eliminate protein aggregates like amyloid‐β‐peptide (Aβ), which are closely linked to Alzheimer’s Disease (AD) pathology. We hypothesize that EVs isolated from human serum post‐exercise could effectively clear Aβ aggregates in neuronal cells. To test this hypothesis, we isolated EVs from cognitively healthy subjects and early onset AD subjects (8 non‐dementia subjects, ND and 4 early AD subjects) 15 minutes after maximal aerobic exercise (EX). EV size did not change with exercise in either ND or AD subjects, while EV concentration increased by 20% post‐EX in both groups. EV function was tested by incubating serum EVs with human neuronal SY5Y cells over expressing β‐amyloid precursor protein (APPswe). We found that post‐EX‐derived EVs were more effective at alleviating Aβ protein aggregation (40% decrease in aggregation compared to pre‐EX‐derived EVs). Heat Shock Proteins (HSPs), molecular chaperones that play a critical role in protein folding/misfolding, were increased in post‐EX EVs. These findings demonstrate a novel way in which exercise could benefit the brain, through the cell‐to‐cell signaling network of extracellular vesicle communication.Support or Funding InformationResearch support by the University of Kansas Alzheimer’s Disease Center.

1948-P: Secretion of the Short-Form Gastric Inhibitory Polypeptide in Nondiabetic and Diabetic Subjects

We previously reported that the short-form gastric inhibitory polypeptide (GIP) 1-30 is released from islet alpha cells and promotes insulin secretion in a paracrine manner in vitro. However, the role played by GIP 1-30 in glucose metabolism in vivo remains unclear. We developed an enzyme-linked immunosorbent assay (ELISA) specific for GIP 1-30 and measured GIP 1-30 secretion in nondiabetic subjects (ND, n = 8) and patients with type 2 diabetes (T2D, n = 9). We developed a sandwich ELISA by combining a novel antibody to the GIP C-terminus with the N-terminal anti-GIP 1-42 antibody that is already available. We explored cross-reactivities with incretins and glucagon-related peptides. We next subjected ND and T2D subjects to the cookie meal test (CMT: carbohydrates 75 g, lipids 28.5 g, proteins 8.5 g) and measured GIP 1-30 blood levels. Absorbance increased in a dose-dependent manner on addition of the GIP 1-30 amide but not GIP 1-42, GLP-1, or glucagon. Post-CMT loading, GIP 1-30 concentrations increased in both ND and T2D subjects; however, in ND subjects, the increases were much lower than those of GIP 1-42 (GIP 1-30, before loading: 1.4 ± 0.5 pmol/L, after: 1.9 ± 0.6 pmol/L; GIP 1-42, before: 8.2 ± 0.1 pmol/L, after: 204.0 ± 35.2 pmol/L, P&amp;lt;0.05). In T2D patients, the GIP 1-30 levels, as assessed by the areas under the curves, tended to be lower than those in ND patients. The DPP-4 inhibitor significantly increased both GIP 1-30 and GIP 1-42 secretion in T2D patients. In conclusion, we developed a novel ELISA that is highly specific for GIP 1-30, the secretion of which was promoted by a mixed meal to a blood level lower than that of GIP 1-42. As is also true of the incretins, GIP 1-30 levels increased upon administration of DPP-4 inhibitor; GIP 1-30 secretion may differ between ND and T2D subjects. Disclosure Y. Takeda: None. Y. Fujita: None. T. Yanagimachi: None. N. Maruyama: Employee; Self; Immuno-Biological Laboratoties Co.,Ltd. R. Bessho: None. H. Sakagami: None. M. Haneda: None. T. Ota: None. Funding Japan Society for the Promotion of Science

1862-P: Insulin-Independent Glucose Utilization during Exercise Is Impaired in Type 1 Diabetes: A New Model Based Analysis

We have previously shown that low insulin coupled with euglycemia or mild hyperglycemia appear to be the most favorable milieu for type 1 diabetes (T1D) during exercise. However, the contributions of insulin-dependent (IDGU) and insulin independent (IIGU) effects of exercise on glucose utilization are unknown. To do so, we studied 6 T1D (age 29±3 years, BMI 28.3±2.0 kg/m2, VO2 max 28.7±2.9 ml/kg/min, mean±SE) and 6 ND (age=28.2±4.2 year, BMI=23.6 ±1.0 kg/m2, VO2 max 36.6±2.9 ml/kg/min) subjects with a glucose clamp, during, before and after a 60 min exercise session at 65% VO2max, on three visits: euglycemia-low insulin (V1); euglycemia-high insulin (V2) and hyperglycemia-low insulin (V3) in random order. Glucose turnover was measured with the isotope dilution technique using [6,6-2H2]glucose. We modified the minimal model to measure the IDGU and IIGU components of glucose utilization (Figure 1, upper panel). Results demonstrate that while IDGU was similar in both groups (data not shown), IIGU (expressed as percent change from baseline) during exercise was significantly lower in T1D than ND subjects, though the trend across the visits were similar (Figure 1, lower panel). Further studies are necessary to determine the cause for this abnormality in T1D to optimize glucose control. Disclosure D. Romeres: None. M. Schiavon: None. A. Basu: Research Support; Spouse/Partner; AstraZeneca. C. Cobelli: None. R. Basu: Other Relationship; Self; AstraZeneca. C. Dalla Man: None. Funding National Institutes of Health (R01090541)

Mitochondrial changes synergize with long chain fatty acid derivatives to support Th17 inflammation in diabetes

Abstract Obesity-associated Type 2 diabetes (T2D) is driven by chronic inflammation. A combinatorial Th17 cytokine profile characterizes and mathematically predicts T2D in people, but the mechanisms that generate the Th17 profile are not clear. We tested the possibility that anaerobic glycolysis, which fuels inflammatory cytokine production from multiple immune cell types, drives the T2D-associated Th17 profile. We showed that activated PBMCs and purified CD4+T cells from T2D subjects prefer anaerobic glucose metabolism to produce ATP regardless of fuel availability. Unexpectedly, glucose starvation did not abrogate the T2D-predictive Th17 profile. Gene expression array suggested that mitochondrial fatty acid uptake catalyzing protein CPT1a differentiated PBMCs from T2D and ND subjects. CPT1a inhibition by etomoxir strongly down-regulated the Th17 profile, surprisingly independent of CPT1a-mediated fatty acid oxidation (OXPHOS). These data suggest that OXPHOS-independent mitochondrial changes that are also glucose-independent support the Th17 profile in T2D. Analyses from T2D vs ND PBMCs showed a lower CACT:CPT1a protein ratio in T2D, indicating defects in lipid uptake and thus defects in lipid flux. We knocked down CACT protein and overloaded PBMCs from lean subjects with fatty acylcarnitines to mimic lipid uptake defects in T2D. 16C-fatty acylcarnitine, but not 6C- or 10C-derivatives, increased frequency of CD4+IL-17+T cells, and phenocopied the Th17 profile only in CACT knockdown cells. 16C-fatty acylcarnitine alone had no effect. We conclude that excessive long chain fatty acylcarnitine combines with dysfunctional mitochondria to support a T2D-associated Th17 profile largely independent of glycolysis.

Nuclear but not mitochondrial-encoded oxidative phosphorylation genes are altered in aging, mild cognitive impairment, and Alzheimer's disease

IntroductionWe have comprehensively described the expression profiles of mitochondrial DNA and nuclear DNA genes that encode subunits of the respiratory oxidative phosphorylation (OXPHOS) complexes (I–V) in the hippocampus from young controls, age matched, mild cognitively impaired (MCI), and Alzheimer's disease (AD) subjects. MethodsHippocampal tissues from 44 non-AD controls (NC), 10 amnestic MCI, and 18 AD cases were analyzed on Affymetrix Hg-U133 plus 2.0 arrays. ResultsThe microarray data revealed significant down regulation in OXPHOS genes in AD, particularly those encoded in the nucleus. In contrast, there was up regulation of the same gene(s) in MCI subjects compared to AD and ND cases. No significant differences were observed in mtDNA genes identified in the array between AD, ND, and MCI subjects except one mt-ND6. DiscussionOur findings suggest that restoration of the expression of nuclear-encoded OXPHOS genes in aging could be a viable strategy for blunting AD progression.

New Locus for Skin Intrinsic Fluorescence in Type 1 Diabetes Also Associated With Blood and Skin Glycated Proteins.

Skin fluorescence (SF) noninvasively measures advanced glycation end products (AGEs) in the skin and is a risk indicator for diabetes complications. N-acetyltransferase 2 (NAT2) is the only known locus influencing SF. We aimed to identify additional genetic loci influencing SF in type 1 diabetes (T1D) through a meta-analysis of genome-wide association studies (N = 1,359) including Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) and Wisconsin Epidemiologic Study of Diabetic Retinopathy (WESDR). A locus on chromosome 1, rs7533564 (P = 1.9 × 10−9), was associated with skin intrinsic fluorescence measured by SCOUT DS (excitation 375 nm, emission 435–655 nm), which remained significant after adjustment for time-weighted HbA1c (P = 1.7 × 10−8). rs7533564 was associated with mean HbA1c in meta-analysis (P = 0.0225), mean glycated albumin (P = 0.0029), and glyoxal hydroimidazolones (P = 0.049), an AGE measured in skin biopsy collagen, in DCCT. rs7533564 was not associated with diabetes complications in DCCT/EDIC or with SF in subjects without diabetes (nondiabetic [ND]) (N = 8,721). In conclusion, we identified a new locus associated with SF in T1D subjects that did not show similar effect in ND subjects, suggesting a diabetes-specific effect. This association needs to be investigated in type 2 diabetes.

Cognitively impaired elderly exhibit insulin resistance and no memory improvement with infused insulin

Insulin resistance is a risk factor for Alzheimer's disease (AD), although its role in AD etiology is unclear. We assessed insulin resistance using fasting and insulin-stimulated measures in 51 elderly subjects with no dementia (ND; n = 37) and with cognitive impairment (CI; n = 14). CI subjects exhibited either mild CI or AD. Fasting insulin resistance was measured using the homeostatic model assessment of insulin resistance (HOMA-IR). Insulin-stimulated glucose disposal was assessed using the hyperinsulinemic-euglycemic clamp to calculate glucose disposal rate into lean mass, the primary site of insulin-stimulated glucose disposal. Because insulin crosses the blood-brain barrier, we also assessed whether insulin infusion would improve verbal episodic memory compared to baseline. Different but equivalent versions of cognitive tests were administered in counterbalanced order in the basal and insulin-stimulated state. Groups did not differ in age or body mass index. Cognitively impaired subjects exhibited greater insulin resistance as measured at fasting (HOMA-IR; ND: 1.09 [1.1] vs. CI: 2.01 [2.3], p = 0.028) and during the hyperinsulinemic clamp (glucose disposal rate into lean mass; ND: 9.9 (4.5) vs. AD 7.2 (3.2), p = 0.040). Cognitively impaired subjects also exhibited higher fasting insulin compared to ND subjects, (CI: 8.7 [7.8] vs. ND: 4.2 [3.8] μU/mL; p = 0.023) and higher fasting amylin (CI: 24.1 [39.1] vs. 8.37 [14.2]; p = 0.050) with no difference in fasting glucose. Insulin infusion elicited a detrimental effect on one test of verbal episodic memory (Free and Cued Selective Reminding Test) in both groups (p < 0.0001) and no change in performance on an additional task (delayed logical memory). In this study, although insulin resistance was observed in cognitively impaired subjects compared to ND controls, insulin infusion did not improve memory. Furthermore, a significant correlation between HOMA-IR and glucose disposal rate was present only in ND (p = 0.0002) but not in cognitively impaired (p = 0.884) subjects, indicating potentially important physiological differences between these cohorts.

Diastolic dysfunction in spontaneous type 2 diabetes rhesus monkeys: a study using echocardiography and magnetic resonance imaging.

BackgroundDiastolic heart failure is a common and deadly complication of diabetes mellitus, with the development of diabetic cardiomyopathy as one of the key determinants of the disease’s complex pathology. The cause of the association is unknown and has no approved therapy strategies as of yet. However significant advances in this area may come from studies on suitable animal models.MethodsA total of 25 male rhesus monkeys (12-16 years, 9-13 kg) were enrolled. Fifteen of them were diagnosed as spontaneous type 2 diabetes mellitus (T2DM, FPG ≥ 104 mg/dl, HbA1c: 4.7-5.5 %, diabetes duration: 1-4 years). The other 10 monkeys were non-diabetic (ND, FPG < 90 mg/dl). Echocardiography and cardiac magnetic resonance were used for evaluating the cardiac structure and function. One T2DM monkey with impaired diastolic function and another ND monkey were both sacrificed to gain the necessary pathology and protein expression studies displayed here.ResultsSix out of 15 T2DM rhesus monkeys were diagnosed with diastolic dysfunction (DD) by echocardiography. Additionally, no abnormalities were found in the group which we determined as the ND monkeys. The six DD monkeys all showed low e’ velocity and decreased e’/a’ ratio, among which three of them showing decreased E/A ratio and the other 3 having elevated E/A ratio, this appears to be similar to the impaired relaxation pattern and pseudonormal pattern found in human patients respectively. The EF and FS of monkeys with pseudonormal pattern decreased significantly compared with ND subjects. A CMR study showed that LVID at end systole of 5 DD monkeys is significantly longer than that of 3 ND monkeys. Of great interest, myocardium lesions and mitochondria impairments and increased expression of AGEs and caspase-3 were found in a sacrificed DD subject.ConclusionThe changes in the imaging and physiological markers of spontaneous T2DM rhesus monkeys are similar to those key markers found in human type 2 diabetes and diastolic dysfunction. This monkey model could help the medical community and us to understand the pathology of this debilitating disease and serve as a beginning to explore important measures to prevent and treat diabetic cardiomyopathy.

Cognitive and Behavioral Determinants of Psychotic Symptoms in Alzheimer's Disease

Aims: To investigate the relationship between psychotic symptoms and cognitive impairment in Alzheimer's disease (AD). Methods: A total of 108 subjects affected by AD were subdivided into subjects without delusions (ND), subjects with paranoid delusions (PD), subjects with delusional misidentifications (DM), subjects with both DM and PD (DM+PD), subjects with visual hallucinations (v-HALL), and subjects without visual hallucinations (N-HALL). Results: PD and ND subjects performed similarly on neuropsychological tests, while DM patients performed significantly worse than PD and ND patients. v-HALL patients performed worse than N-HALL patients on memory, visuospatial, and executive functions. As for behavioral features, DM and v-HALL subjects reported higher scores on the abnormal motor behavior subscale of the neuropsychiatric inventory (NPI); PD subjects reported higher scores on the disinhibition subscale of the NPI. The severity of PD was predicted by the severity of disinhibition (B = 0.514; p = 0.016) but not by neuropsychological performances. The severity of DM was predicted by age (B = 0.099; p = 0.048) and MMSE (B = -0.233; p = 0.001). The severity of v-HALL was predicted by age (B = 0.052; p = 0.037) and scores on an immediate visual memory task (B = -0.135; p = 0.007). Conclusions: The occurrence of PD may require the relative sparing of cognitive functions and be favored by frontal lobe dysfunction, while DM is associated with the overall level of cognitive impairment. Finally, v-HALL are associated with the impairment of visuospatial abilities.

Effects of transaldolase exchange on estimates of gluconeogenesis in type 2 diabetes

Transaldolase (TA) exchange overestimates gluconeogenesis measured with deuterated water (²H₂O). However, it is unknown whether TA differs in people with type 2 diabetes (T2DM). ²H₂O was ingested, and [1-¹³C]acetate and [3-³H]glucose were infused in T2DM (n = 10) and healthy nondiabetic (ND; n = 8) subjects. TA was assessed from the ratio of ¹³C3 to ¹³C4 glucose enrichment (¹³C3/¹³C4) measured by ¹³C NMR. Glucose turnover was measured before (~16-h fast) and during hyperglycemic (~10 mM) moderate-dose insulin (~0.35 mU·kg⁻¹·min⁻¹) clamp. ¹³C3/¹³C4 in T2DM vs. ND was <1.0 and not different at baseline and clamp, indicating equivalent TA. To determine whether incomplete triose phosphate isomerase (TPI) exchange contributed to asymmetric ¹³C3/¹³C4, [U-¹³C]glycerol was infused in lieu of [1-¹³C]acetate during a separate visit in a subset of ND (n = 7) subjects. Ratio of ¹³C3/¹³C4 obtained following either tracer was <1.0 at baseline and during clamp, indicating that TPI exchange was essentially complete and did not contribute to asymmetric glucose enrichment. Uncorrected and corrected rates of gluconeogenesis were no different (P = not significant) in T2DM vs. ND both at baseline and during clamp. TA correction resulted in equivalent estimates of corrected gluconeogenesis in T2DM and ND that were ~25-35% lower than uncorrected gluconeogenesis both at baseline and during the clamp. The asymmetric enrichment of glucose from ¹³C-gluconeogenic tracers is attributable to TA exchange and can be utilized to correct for TA exchange. In conclusion, TA exchange does not differ between T2DM and ND under fasting or hyperglycemic clamp conditions, and the ²H₂O method continues to provide an accurate estimation of gluconeogenesis.

New visual rating system for medial temporal lobe atrophy: a simple diagnostic tool for routine examinations

We estimated the usefulness of our new scale to rate medial temporal atrophy with short inversion time inversion recovery images. Alzheimer's disease (AD) subjects (n= 34) and non-demented subjects (n= 19) were recruited for this study. First, coronal short inversion time inversion recovery images were scanned vertical to the long axis of hippocampus. Next, the single image in which peduncles appeared widest was adopted for estimation. The parahippocampal cerebrospinal fluid space was divided into three parts: the outer, upper and inner parts. The hippocampus was defined as a structure being of equal intensity to grey matter. Two radiologists compared each part of the parahippocampal cerebrospinal fluid space with the hippocampus and rated them on a 0-3 scale. Interrater and intrarater kappa statistics and sensitivity/specificity for the diagnosis of AD were calculated using the scores of the right, left and both sides combined. There were no significant differences between AD and ND subjects with regards to sex. AD subjects had lower Mini-Mental State Examination scores and were older than non-demented subjects. Interrater and intrarater kappa statistics were 0.52-0.68 and 0.76-0.83, respectively. Sensitivity was 88.2% using the scores of both sides. Interrater and intrarater agreements were fair to good and good to excellent, respectively. Our new visual rating method detected medial temporal atrophy in AD patients at a highly sensitive rate. As such, we conclude that this visual rating scale is useful for judging medial temporal atrophy simply and objectively in clinical use, and it is helpful in establishing an AD diagnosis.

Mental and behavioral symptoms of person's with Asperger's syndrome: Relationships with social isolation and handicaps

People with Asperger's syndrome (AS) experience mental comorbidities, and behavioral symptoms that can deepen social isolation and handicaps. We compared the frequency of mental and behavioral symptoms, motor abnormality, and life history between adults with AS and those with no mental disorders but with disturbance of social functions and communication skills (ND) from our outpatient clinic. Participants with AS (n=99) as compared with ND subjects (n=63) showed significant higher rate of depressive mood, anxiety, unstable emotion, mood swings, oversensitivity to normal situation obsessive compulsive symptoms, persecutory idea, loss of energy, insomnia carelessness, restlessness, confusion in new environments, episodic agitation, inflexible adherence, egocentric behavior, self harm, circumscribed interest, poor lifestyle habits, non-athleticism, clumsiness, bulling at school, school non-attendance, social withdrawal, and lack of friendships. In AS, emotional instability and confusion in new environments might lead to social isolation. The findings demonstrated that individuals with AS experience greater social isolation and distress, as well as a wider range of mental and behavioral symptoms and disturbances of motor skills as compared to healthy subjects with disturbances of social functions and communication skills. These factors are interrelated and may be used as supplementary methods for differential diagnosis of AS from other conditions.

Amnestic Mild Cognitive Impairment and Early Alzheimer’s Disease in an Asian Memory Clinic – Evidence for a Clinical Spectrum

Objectives: To determine if mild cognitive impairment (MCI) represents a continuum of cognitive and functional deficits. Methods: Clinical data of 164 subjects with no dementia (ND, n = 52), uncertain dementia (n = 69), and mild probable Alzheimer’s disease (AD, n = 43) were reviewed. Uncertain dementia patients were classified as pre-MCI (n = 11), early amnestic MCI (e-aMCI, n = 15) and late amnestic MCI (l-aMCI, n = 15). Cognitive assessments [Chinese Mini-Mental State Examination (CMMSE) and a validated neuropsychological battery], functional assessments (Lawton’s scale for instrumental activities of daily living) and neuroimaging (ischemic lesions and medial temporal lobe atrophy) were reviewed. Results: ND, aMCI and mild AD subjects demonstrated a significant trend for worsening performance for all cognitive and functional measures (ANOVA, p < 0.05). Pre-MCI subjects performed significantly better than aMCI subjects in all verbal memory domains (p < 0.001), while l-aMCI had worse functional performance (p = 0.007), a trend towards greater depressive symptoms (p = 0.05) and higher medial temporal lobe atrophy scores (p = 0.06). l-aMCI subjects were more likely than either pre-MCI or e-aMCI to progress to dementia over a mean follow-up period of 2.5 years (46.7 vs. 9.1 and 20.0%, respectively). Conclusions: Clinical delineation of aMCI allows the differentiation of those likely to progress for better correlation to biomarker development.

TLR4 and RAGE: Similar routes leading to inflammation in type 2 diabetic patients

Aim The present study investigates the interaction of TLR4 and RAGE with their respective ligands as inducers of the inflammatory markers IL-6 and TNF-α. Also, the reactivity of peripheral blood mononuclear cells (PBMNC) from type 2 diabetic (T2D) patients and non-diabetic healthy controls (ND) were comparatively studied. Methods Concentrations of IL-6 and TNF-α were measured by sandwich Elisa, using kits supplied by Assay Designs (Ann Arbor, MI, USA). PBMNC from T2D and ND were incubated in the presence or absence of LPS, anti-TLR4 or anti-RAGE for 72 hours at 37° C under 5% CO 2. The final volume was adjusted to 300 μL in DMEM supplemented with 10% fetal bovine serum. After incubation, the cells were centrifuged, the supernatant collected and the cytokines measured. Results PBMNC from T2D were more sensitive to innate immune stimulation with LPS and monoclonal agonist anti-TLR4 than were cells from ND. The actions of LPS, anti-TLR4 and anti-RAGE potentiated the production of IL-6 and TNF-α in both groups. The simultaneous activation of monoclonal anti-RAGE and anti-TLR4 suggests that both antibodies used different receptors on the cell surface, but converged on the same PBMNC signaling metabolic pathways. This simultaneous activation induced a higher production of IL-6 and TNF-α in PBMNC from the T2D patients than from the ND subjects. Conclusion Our results clearly show an exacerbation of innate immunity in PBMNC with T2D that was possibly hyperglycaemia-induced. These data, when analyzed together, suggest the importance of innate immunity in the pathogenesis of T2D.

Combination of CSF N -acetylaspartate and neurofilaments in multiple sclerosis

Axonal degeneration is the likely cause of disease progression in multiple sclerosis (MS). Our previous results indicated that neuron-specific N-acetylaspartate (NAA) is a candidate CSF biomarker for disease progression in MS. The aim of this study was to explore the potential of NAA as an early biomarker of axonal damage in MS. Next, we wanted to know the additional value of measurement of NAA compared to other candidate markers for axonal damage, such as neurofilament subunits and tau protein. Levels of NAA, neurofilament light, neurofilament heavy, and tau were determined in CSF of patients with clinically isolated syndrome (CIS, n = 38), relapsing-remitting MS (RRMS, n = 42), secondary progressive MS (SPMS, n = 28), and primary progressive MS (PPMS, n = 6); patients without neurologic disease (ND, n = 28); noninflammatory neurologic controls (n = 18); and inflammatory neurologic controls (n = 39). CSF NAA levels were decreased in patients with SPMS compared to ND controls, patients with CIS, and patients with RRMS. CSF NAA levels in patients with CIS and RRMS were similar to those in ND subjects. All axonal damage proteins showed specific patterns of changes and relations with disease activity measures. The neurofilament light chain levels were already increased in patients with CIS, especially in patients who converted to MS. The neurofilament heavy chain levels were highest in the patients with SPMS. Tau levels were similar in MS and ND. CSF N-acetylaspartate (NAA) levels were not different from patients without neurologic disease in early stages of multiple sclerosis, though decreased as the disease progressed. Combining CSF NAA and neurofilament levels yields information on different phases of axonal pathology.

Features of an exceptionally narrow QRS data set

Background Little attention has been directed to the characteristics of electrocardiograms (ECGs) with brief QRS durations (BD). Methods From a database of 859 977 computer-analyzed (Marquette 12SL, GE Healthcare, Milwaukee, WI, USA) ECGs of 216 148 patients, 1805 patients (data set of BD: 19 718 ECGs; age, >18 years, unpaced), had, in at least one ECG, a QRS duration of less than 62 milliseconds, a prevalence of 0.8%. Results The QRS duration ranged from 46 to 188 milliseconds; values fluctuated between excessive brevity and the traditionally normal (80-95 milliseconds), with many values in the 60's. The average age at first acquisition was 56 years (range, 18-96 years); 1371 were female (76%) and 433 were males (24%); and 416 were white (23%), 1243 African American (69%), 109 other (6%). The summed 12-lead QRS amplitude (ΣQRS) ranged from 2800 to 32 929 μV (mean ± SD, 11 154 ± 4101), and heart rate ranged from 40 to 269 (98 ± 26). There was a statistically positive relationship between QRS duration (in the range 52-105 milliseconds) and ΣQRS ( P < 0001): for each 1000 μV increment, duration increased by 0.7 milliseconds (95% confidence interval [CI], 0.66-0.73 milliseconds). Conversely, for each 5-millisecond increment in duration, ΣQRS increased by 475 μV (95% CI, 450-498 μV). There was an inverse relationship between QRS duration and heart rate ( P < .0001): for every 10 beat rate increase, the duration dropped by 1.14 milliseconds (95% CI, 1.09-1.19 milliseconds). An additional data set of normal QRS durations ND consisted of 2902 subjects, none of whose 40 327 ECGs showed a QRS duration less than 62 milliseconds; 2.8% of ND ECGs had durations in the 62–69 millisecond range, 26% in BD. Sinus tachycardia was 43% in BD and 24% in ND. The average age of ND was 58 years (range, 18-100 years); 44% were male and 56% female; and 39% were white and 57% were African American. A positive relationship between duration and amplitude was found among ND subjects as well: for each 1000 point increase in ΣQRS, duration increased by 0.45 milliseconds ( P < .0001; 95% CI, 0.42-0.47 milliseconds). The duration amplitude relationship did not hold for durations greater than 105 milliseconds in either data set. Conclusion Over the full extended span of QRS durations (46-106 milliseconds), the value of the latter is directly related to the total summed amplitude of the 12-lead QRS. An inverse relationship is demonstrable with heart rate.