In Quest of Pathognomonic/Endophenotypic Markers of Attention Deficit Hyperactivity Disorder (ADHD): Potential of EEG-Based Frequency Analysis and ERPs to Better Detect, Prevent and Manage ADHD.

Attention deficit hyperactivity disorder (ADHD) is a chronic heritable developmental delay psychiatric disorder requiring chronic management, characterized by inattention, hyperactivity, hyperkinectivity and impulsivity. Subjective clinical evaluation still remains crucial in its diagnosis. Discussed are two key aspects in the "characterizing ADHD" and on the quest for objective "pathognomonic/endophenotypic diagnostic markers of ADHD". The first aspect briefly revolves around issues related to identification of pathognomonic/endophenotypic diagnostic markers in ADHD. Issues discussed include changes in ADHD definition, remission/persistence and overlapping-symptoms cum shared-heritability with its co-morbid cross-border mental disorders. The second aspect discussed is neurobiological and EEG-based studies on ADHD. Given the neurobiological and temporal aspects of ADHD symptoms the electroencephalograph (EEG) like NeuralScan by Medeia appears as an appropriate tool. The EEGs appropriateness is further enhanced when coupled with suitable behavior/cognitive/motor/psychological tasks/paradigms yielding EEG-based markers like event-related-potential (ERPs like P3 amplitudes and latency), reaction time variability (RTV), Theta:Beta ratio (TBR) and sensorimotor rhythm (SMR). At present, these markers could potentially help in the neurobiological characterization of ADHD and either help in identifying or lay the groundwork for identifying pathognomonic and/or endophenotypic EEG-based markers enabling its diagnosis, treatment and management.

ALTERED CIRCULATING LEVELS OF RETINOL BINDING PROTEIN 4 AND TRANSTHYRETIN IN RELATION TO INSULIN RESISTANCE, OBESITY, AND GLUCOSE INTOLERANCE IN ASIAN INDIANS.

OBJECTIVE: Retinol binding protein 4 (RBP4) has been implicated in metabolic disorders including type 2 diabetes mellitus (T2DM), but few studies have looked at transthyretin (TTR) with which RBP4 is normally bound to in the circulation. We report on the systemic levels of RBP4 and TTR and their associations with insulin resistance, obesity, prediabetes, and T2DM in Asian Indians. METHODS: Age-matched individuals with normal glucose tolerance (NGT, n = 90), impaired glucose tolerance (IGT, n = 70) and T2DM (n = 90) were recruited from the Chennai Urban Rural Epidemiology Study (CURES). Insulin resistance was estimated using the homeostasis model assessment of insulin resistance (HOMA-IR). RBP4 and TTR levels were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: Circulatory RBP4 and TTR levels (in µg/mL) were highest in T2DM (RBP4: 13 ± 3.9, TTR: 832 ± 310) followed by IGT (RBP4: 10.5 ± 3.2; TTR: 720 ± 214) compared to NGT (RBP4: 8.7 ± 2.5; TTR: 551 ± 185; P<.001). Compared to nonobese NGT individuals, obese NGT, nonobese T2DM, and obese T2DM had higher RBP4 (8.1 vs. 10.6, 12.1, and 13.2 µg/mL, P<.01) and TTR levels (478 vs. 737, 777, and 900 µg/mL, P<.01). RBP4 but not TTR was significantly (P<.001) correlated with insulin resistance even among NGT subjects. In regression analysis, RBP4 and TTR showed significant associations with T2DM after adjusting for confounders (RBP4 odds ratio [OR]: 1.107, 95% confidence interval [CI]: 1.008-1.216; TTR OR: 1.342, 95% CI: 1.165-1.547). CONCLUSION: Circulatory levels of RBP4 and TTR showed a significant associations with glucose intolerance, obesity, T2DM and RBP4 additionally, with insulin resistance.

Prevalence of overweight and obesity among school children and adolescents in Chennai.

OBJECTIVE: To determine the prevalence of overweight and obesity among children and adolescents in Chennai, India, using national and international age- and sex- specific body mass index (BMI) cut-off points. METHODS: The Obesity Reduction and Awareness and Screening of Non communicable diseases through Group Education in Children and Adolescents (ORANGE) project is a cross-sectional study carried out on 18,955 children (age 6-11 years) and adolescents (age 12-17 years) across 51 schools (31 private and 20 government) of Chennai. Overweight and obesity was classified by the International Obesity Task Force (IOTF 2000) and Khadilkars criteria (2012), and Hypertension by the IDF criteria (in children ≥10 years and adolescents). RESULTS: The prevalence of overweight/obesity was significantly higher in private compared to government schools both by the IOTF criteria [private schools: 21.4%, government schools: 3.6%, (OR: 7.4, 95% CI:6.3-8.6; P<0.001) and by Khadilkar criteria (private school: 26.4%, government schools: 4.6% OR: 6.9, 95% CI:6.2-7.8; P<0.001). Overweight/obesity was higher among girls (IOTF: 18%, Khadilkar: 21.3%) compared to boys (IOTF: 16.2%, Khadilkar: 20.7%) and higher among adolescents (IOTF: 18.1%, Khadilkar: 21.2%) compared to children (IOTF: 15.5%, Khadilkar: 20.7%). Prevalence of hypertension was 20.4% among obese/overweight and 5.2% among non-obese (OR 4.7, 95%CI: 4.2-5.3, P<0.001). CONCLUSIONS: The prevalence of overweight and obesity is high among private schools in Chennai, and hypertension is also common.

Serum adiponectin helps to differentiate type 1 and type 2 diabetes among young Asian Indians.

OBJECTIVE: This study assessed whether serum adiponectin could be used as a biochemical marker to differentiate type 1 diabetes mellitus (T1DM) from type 2 diabetes mellitus (T2DM) among young Asian Indians. RESEARCH DESIGN AND METHODS: We recruited age- and sex-matched individuals with physician-diagnosed T1DM (n=70) and T2DM (n=72). All were 12-27 years of age with a duration of diabetes of >2 years, at a large tertiary-care diabetes center in Chennai, southern India. Age- and sex-matched individuals with normal glucose tolerance (NGT) (n=68) were selected from an ongoing population study. NGT was defined using World Health Organization criteria. Serum total adiponectin was measured by enzyme-linked immunosorbent assay. Receiver operating characteristic (ROC) curves were used to identify adiponectin cut points for discriminating T1DM from T2DM. RESULTS: Adiponectin levels were higher in T1DM and lower in T2DM compared with the NGT group (9.89, 3.88, and 6.84 µg/mL, respectively; P<0.001). In standardized polytomous regression models, adiponectin was associated with T1DM (odds ratio [OR]=1.131 per SD; 95% confidence interval [CI], 1.025-1.249) and T2DM (OR=0.628 per SD; 95% CI, 0.504-0.721) controlled for age, gender, waist circumference, body mass index, hypertension, glycated hemoglobin, total cholesterol, serum triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, family history of T2DM, and estimated glomerular filtration rate. Using ROC analysis, an adiponectin cut point of 5.1 µg/mL had a C statistic of 0.886 (95% CI, 0.836-0.953), sensitivity of 80.6%, and specificity of 80.6% to differentiate T1DM from T2DM. Using the 5.1 µg/mL cut point, 80.6% of T1DM and 81.8% of T2DM would be correctly classified. CONCLUSIONS: Serum adiponectin is a useful biochemical marker for differentiating T1DM and T2DM among young Asian Indians.

Human islet mass, morphology, and survival after cryopreservation using the Edmonton protocol.

The aim of this study was to assess recovery, cell death, and cell composition of post-thaw cultured human islets. Cryopreserved islets were provided by the Clinical Islet Transplant Program, Edmonton, Canada. Islets were processed using media prepared in accordance with Pre-Edmonton and Edmonton protocols. Cryopreserved islets were rapidly thawed and cultured for 24 h, 3 d, 5 d, and 7 d, following which they were processed for histology. Islet quantification, integrity, morphology and tissue turnover were studied via hematoxylin and eosin stained sections. Ultrastructure was studied by electron microscopy and endocrine cell composition by immunohistochemistry. Using the Pre-Edmonton protocol, islet recovery was 50.1% and islet survival was 50% at 24 h while for the Edmonton protocol, the islet recovery was 69.4% (p<0.001) and islet survival, 50% at ≈2.5 d. With an increasing culture duration although the physical integrity was retained there was an increasing loss of cohesivity both at light microscopic and at ultrastructure level regardless of the protocols used. Percentage islet survival and tissue turnover correlated negatively with culture duration in both protocols. The Edmonton protocol appears to preserve the islets better. However, culture duration adversely affects islet survival and quality, indicating the need for more optimal cryopreservation and culture techniques.