8 research outputs found
On Λ-Fractional Derivative and Human Neural Network
Fractional derivatives can express anomalous diffusion in brain tissue. Various brain diseases such as Alzheimer’s disease, multiple sclerosis, and Parkinson’s disease are attributed to the accumulation of proteins in axons. Discrete swellings along the axons cause other neuro diseases. To model the propagation of voltage in axons with all those causes, a fractional cable geometry has been adopted. Although a fractional cable model has already been presented, the non-existence of fractional differential geometry based on the well-known fractional derivatives raises questions. These minute parts of the human neural system are modeled as cables that function with a non-uniform cross-section in the fractional realm based upon the Λ-fractional derivative (Λ-FD). That derivative is considered the unique fractional derivative generating differential geometry. Examples are presented so that fruitful conclusions can be made. The present work is going to help medical and bioengineering scientists in controlling various brain diseases
Association Between Polymorphisms in MTHFR and APOA5 and Metabolic Syndrome in the Greek Population
Impaired energy homeostasis and low-grade inflammation have been related to components of the metabolic syndrome (MetS) such as dyslipidemia, obesity, and insulin resistance. Single-nucleotide polymorphisms in the genes encoding for IL-6 (g.-634G>C; c.174G>C), TNF alpha (g.-308G>A), methylenetetrahydrofolate reductase (MTHFR) (c.677C>T), APOC3 (c.3175C>G), and APOA5 (g.-1131T>C) have been implicated in the processes of inflammation and energy intake that take place in the development of MetS manifestations. The aim of this study was to investigate the association between these polymorphisms and MetS, as defined by the National Cholesterol Education Program-Adult treatment Panel III criteria, in the Greek population. Overall, 30 unrelated subjects who met the criteria of MetS and 60 matched control subjects from central Greece were genotyped by polymerase chain reaction-restriction fragment length polymorphism analysis. There was a significant association between both MTHFR c.677C>T (odds ratio: 4.02; confidence interval: 1.496-10.777; p = 0.003) and APOA5 g.-1131T>C (odds ratio: 3.514; confidence interval: 1.065-11.585; p = 0.035) and MetS. Analysis of constructed haplotypes showed a highly significant association between 677C-1131T-3175C haplotype and MetS (p<0.0001). Carriers of both MTHFR c.677T and APOA5 g.-1131C were associated with increased triglyceride levels (p = 0.001 and p = 0.003, respectively), compared with noncarriers. These results support a role for MTHFR and APOA5 as risk factors for MetS and suggest their further validation in larger independent populations
Elevated circulating levels of lipoprotein-associated phospholipase A2 in obese children
Obesity and cardiovascular disease (CVD) often co-exist, but the pathophysiologic mechanisms that link the two are not fully understood. Lipoprotein-associated phospholipase A2 (Lp-PLA2) is involved in the modification of lipids within atheromatous plaques. Recently, circulating Lp-PLA2 was found to be predictive of thromboembolic episodes in adults, independently of a variety of other potential risk factors, including markers of inflammation, renal function, and hemodynamic stress. However, the function of this lipase and its importance as a biomarker in childhood obesity is much less studied. The aim of the study was to study Lp-PLA2, a non-traditional risk factor of CVD, in obese children. Methods: Sixty-seven lean [39 boys and 28 girls, mean body mass index (BMI) z-score-0.2±0.8] and 66 obese (32 boys and 34 girls, mean BMI z-score 4.4±1.2) age-matched (p=0.251) children, aged 6-12 years, were studied. BMI z-score was calculated based on the Greek BMI growth curves, and children were categorized as obese according to the Cole criteria. All children underwent physical examination and a fasting morning blood sample was obtained for glucose, insulin, lipid profile, and Lp-PLA2 assessment. Plasma concentrations of Lp-PLA2 were determined by a commercially available Lp-PLA2 enzyme-linked immunosorbent assay kit (PLAC Test), while other measurements were performed using standard methods. Results: Plasma Lp-PLA2 levels were significantly higher in obese children (322.5±77.8 ng/mL) compared with normal-weight ones (278.0±64.4 ng/mL, p&lt;0.001). Lp-PLA2 concentrations were significantly correlated with the BMI z-score (p=0.004). Receiver operating characteristic analysis on Lp-PLA2 values resulted in significant areas under the curve (AUC) for distinguishing between obese and normal-weight groups of children (AUC, 0.726; p&lt;0.001). Conclusions: We found significantly higher Lp-PLA2 levels in obese children than lean controls. Interestingly, they all had levels &gt;200 ng/mL, which are considered to correlate with atherosclerosis and a high thromboembolic risk in adults. The positive correlation of Lp-PLA2 with BMI suggests that Lp-PLA2 might be the link between obesity and increased cardiovascular risk, which can be elevated even at a very young age. Measurement of Lp-PLA2 in plasma could therefore represent a further biomarker for assessing increased CVD risk in obese children and adolescents. © 2015 by De Gruyter