Mitsuhiko Hara

Abdominal adiposity is associated with fatty acid desaturase activity in boys: Implications for C-reactive protein and insulin resistance

Fatty acid composition, which is altered in patients with abdominal obesity, is influenced not only by dietary intake but also by the desaturating enzymes stearoyl-CoA desaturase (SCD), delta-6 desaturase (D6D) and delta-5 desaturase (D5D). We investigated desaturase activities and their associations with metabolic risk factors, C-reactive protein levels (CRP) and insulin resistance in Japanese children. There were 237 school children in this study; 115 were boys. The fatty acid composition of plasma phospholipids was analyzed, and the following desaturase activities were estimated: SCD (16:1n-7/16:0 and 18:1n-9/18:0), D6D (20:3n-6/18:2n-6) and D5D (20:4n-6/20:3n-6). D6D and D5D activities, but not SCD activity, were significantly associated with triglyceride levels, high-density lipoprotein cholesterol levels and insulin resistance in both sexes, and with CRP levels in boys. In addition, increased abdominal adiposity was significantly associated with increased D6D activity, and decreased D5D activity and insulin resistance in both sexes, and with increased CRP levels in boys. The n-6 polyunsaturated fatty acid desaturation pathway may be associated with metabolic risk factors, insulin resistance and increased inflammation in children with abdominal obesity, especially in boys.

Assessment of body composition measured by bioelectrical impedance in children

Bioelectorical impedance methods have been found to be a valid and reliable way of estimating per cent body fat (%BF) in adults. We applied them to healthy children and compared them with conventional anthropometry methods.

Threshold values of visceral fat and waist girth in Japanese obese children

Abstract Background : In order to define the diagnostic criteria for visceral adipose tissue (VAT) accumulation and abdominal obesity in Japanese youths, a cross‐sectional, multicenter study was conducted.

Lipoprotein (a) and apolipoprotein A‐1 and B in schoolchildren whose grandparents had coronary and cerebrovascular events: A preliminary study of 12–13 year old Japanese children

The aim of this study was to evaluate the relationship between the serum levels of lipoprotein (a) [Lp (a)] and apolipoproteins (apo A‐1 and apo B) in schoolchildren with a history of coronary and cerebrovascular events in their grandparents.

Characteristics of obese children with low content of arachidonic acid in plasma lipids

Background: Although there have been many studies on the relationship between obesity and long‐chain polyunsaturated fatty acid (LCPUFA), the results and their interpretation are controversial, especially in children. Arachidonic acid (AA), the product of n‐6 LCPUFA, is reported to be related to insulin resistance. The purpose of the present paper was to investigate the LCPUFA profile in obese children and mechanisms that contribute to reduced AA content.

Serum lipid profile in obese children in China

Abstract Background : The aim of the present study was to examine the serum lipid profile in obese Chinese children, their serum lipid and apolipoprotein A‐I (apoA‐I) and B (apoB) levels were examined.

Abdominal adiposity is associated with high-density lipoprotein subclasses in Japanese schoolchildren.

BACKGROUND The large HDL subclass is considered to possess cardioprotective properties. The purpose of this study is to determine the relationship among abdominal adiposity, insulin resistance and HDL subclass profiles of Japanese schoolchildren. METHODS The study subjects included 164 children (79 boys and 85 girls). We obtained waist to height ratio (WHtR), lipid profile, and HOMA-IR. The HDL subclass profile was analyzed by HPLC. RESULTS Children of either sex with abdominal obesity (WHtR≥0.5) had reduced concentrations of very large, large, and medium HDLC in conjunction with elevated triglyceride (TG) concentrations and HOMA-IR. WHtR was inversely related to the concentrations of very large (boys: r=-0.5306, p<0.0001; girls: r=-0.3483, p=0.0011), large (r=-0.6168, p<0.0001; r=-0.4387, p<0.0001), and medium (r=-0.4170, p=0.0001; r=-0.4116, p<0.0001) HDLC. The multiple regression analyses revealed that WHtR was an independent factor of the concentrations of very large, large, small, and very small HDLC in boys and the concentrations of large and medium HDLC in girls. CONCLUSIONS In Japanese schoolchildren, abdominal obesity is associated with atherogenic HDL subclass profile. Abdominal obesity may be an important target for the prevention and management of HDL subclass alteration, even in children who do not suffer from insulin resistance or hypertriglyceridemia.

Relationship between fat distribution and lipid and apolipoprotein profiles in young teenagers

The influence of obesity and fat distribution on serum levels of lipoprotein and apolipoprotein was investigated in 294 Japanese junior high school children (12‐13 years of age). Serum levels of low‐density lipoprotein cholesterol (LDLC) (P= 0.013), triglycerides (TG) (P= 0.0006), and apolipoprotein B (apoB) (P= 0.003), and the apoB/A‐I ratio (P= 0.005) were significantly higher and serum levels of high‐density lipoprotein cholesterol (HDLC) (P= 0.00003) and apoA‐1(P = 0.003) were significantly lower in obese boys than in non‐obese boys. The serum levels of TG (P = 0.013) and the apoB/A‐1 ratio (P= 0.011) were significantly higher and the serum levels of HDLC (P= 0.004) was significantly lower in obese girls than in non‐obese girls. The LDLC/apoB ratio was lower in obese girls than in non‐obese girls (P= 0.03). Obesity ( 20% of ideal weight) was strongly correlated with the serum levels of lipids and apolipoproteins in boys; this relationship was less clear in girls. The degree of obesity and the body mass index (BMI) were more strongly correlated with serum levels of lipids and apolipoproteins in boys than in girls. In boys, atherogenic‐lipoproteins and apolipoproteins, such as LDLC and apoB, showed a stronger correlation with the thickness of the triceps skinfold, while in girls the anti‐atherogenic lipoproteins and apolipoproteins, such as HDLC and apoA‐1, showed a stronger correlation with both the triceps and the subscapular skinfold thicknesses. In girls the relationships between the BMI and the degree of obesity and the thickness of the subscapular skinfold (S) thickness were similar to the relationships between those parameters and the triceps skinfold (T) thickness. In boys, these parameters showed a stronger correlation with the subscapular skinfold thickness than with the triceps skinfold thickness. The correlation coefficients for the relationships between skinfold thickness and lipid and apolipoprotein levels were similar to the coefficients for the relationships between skinfold thicknesses and the severity of obesity and the BMI. The distribution of central‐type fat accumulation, which is indicated by the thickness of the subscapular skinfold, the S/T ratio and S‐T value, was inversely correlated with the HDLC level in both boys and girls. The degree of obesity was strongly correlated with the atherogenic lipoprotein profile in boys, in part because the subscapular skinfold thickness was strongly correlated with the degree of obesity and the BMI. In girls, the correlations between indices of central‐type obesity and atherogenic lipid and apolipoprotein profiles were stronger than in boys. These data suggest that childhood obesity may be an early cardiovascular risk factor.

Relationship of apolipoprotein E phenotypes to serum lipid and lipoprotein levels in Japanese schoolchildren.

The distribution of apolipoprotein (apo) E phenotypes was investigated in Japanese schoolchildren and an attempt was made to determine whether the apoE phenotypes influence the serum levels of lipid and lipoprotein. The subjects were 289 children from ajunior high school (145 M, 144 F, aged 12–13 y). TheE3/3 phenotype was demonstrated in 69.9%, E4/3 in 18.7%, E2/3 in 9.0%, E4/2 in 1.4%, E4/4 in 0.7% and E5/4 in 0.3%. E2/2 was not detected. Serum levels of total cholesterol and low‐density lipoprotein‐cholesterol were progressively lower in the phenotypes E4/3, E3/3 and E2/3. The serum level of high‐density lipoprotein‐cholesterol showed a progressive increase in the same order. In conclusion, Japanese schoolchildren with E4/3 already had an atherogenic serum lipid profile.

The Use of Susceptibility-Weighted Imaging for Epileptic Focus Localization in Acute-Stage Pediatric Encephalopathy: A Case Report

BACKGROUND Susceptibility-weighted imaging is a novel high-spatial-resolution three-dimensional gradient-echo magnetic resonance imaging technique with phase postprocessing that accentuates the paramagnetic properties of blood products. The use of susceptibility-weighted imaging for epileptic focus localization in the acute stage of encephalopathy in a child has not been documented. PATIENTS We report three pediatric patients with status epilepticus in the setting of fever, in whom susceptibility-weighted imaging showed transient prominence of the focal venous vasculature. RESULTS Conventional cranial T1- and T2-weighted images and diffusion-weighted images showed no abnormalities. The prominence of the focal venous vasculature in these patients, as demonstrated by susceptibility-weighted imaging, was consistent with the epileptic focuses suggested by both clinical symptoms and electroencephalograph findings and resolved completely without neurological sequelae in all patients. CONCLUSIONS Susceptibility-weighted imaging may facilitate assessing epileptic focus localization in the acute stage of encephalopathy in children.