Amelioratory effects of testosterone propionate supplement on behavioral, biochemical and morphological parameters in aged rats

Testosterone has been shown to affect motor behavior and nigrostriatal dopaminergic (NSDA) system in young and adult male rats. However, it is not known whether exogenous testosterone intervention to aged male rats can ameliorate age-related motor impairment. Thus, in the present study, the open field motor behavior and adhesive tape removal motor performance as well as the expression of tyrosine hydroxylase (TH) and dopamine transporter (DAT) of NSDA system were examined in aged male rats following chronic subcutaneous injections of testosterone propionate (TP). Aged rats showed significantly reduced open field motor behavior and adhesive tape removal motor performance compared to adult rats. Chronic TP supplement significantly ameliorated the age-related motor deficits. The expression of TH and DAT of NSDA system was significantly enhanced in TP-treated aged rats revealed by RT-PCR, Western blot and immunohistochemistry analysis respectively. The results imply that chronic TP treatment may favorably improve the declined motor behavior and motor performance with aging. Testosterone propionate supplement that facilitated NSDA system may influence the maintenance of motor behavior and performance in aged rats.     

Quantitative assessment of left ventricular systolic function in patients with coronary heart disease by velocity vector imaging

Objective: To assess the left ventricular (LV) longitudinal systolic function and asynchrony in patients with coronary atherosclerotic heart disease (CAD) by syngo velocity vector imaging (VVI). Methods: Twenty‐eight control subjects and 79 patients with CAD were examined, including 28 patients with myocardial infarction, 26 patients with coronary lumen stenosis <50%, and 25 patients with myocardial ischemia. According to the results of coronary arteriography and electrocardiogram (ECG), the myocardial segments of the LV of CAD patients were divided into four groups: ischemic, infarcted, nonischemic, and normal. Dynamic imaging was performed on all subjects. The systolic peak strain (Smax), systolic strain rate (SRmax), time to peak strain (PTs), and time to peak strain rate (PTsr) in every cardiac cycle were measured. Results: A total of 1,253 out of 1,712 (96.5%) segments were successfully analyzed with VVI. Smax and SRmax of the ischemic and infarcted segments were impaired in CAD patients. Optimal sensitivity and specificity were obtained with strain and strain rate cutoffs of ?14.08% and ?0.83 s^?1, respectively, for detecting ischemic segments and ?6.65% and ?0.38 s^?1, respectively, for detecting infarcted segments. The PTs and PTsr were significantly longer in the ischemic and infarcted segments compared to those of the control group. Conclusions: Utilizing VVI, the longitudinal strain, strain rate, and peak time in CAD patients are easy to obtain and reproducible. Strain and strain rate cutoff values of abnormal myocardium are valuable for detecting ischemia and infarction. The PTs and PTsr values possibly estimate myocardium asynchrony in CAD patients. (Echocardiography 2012;29:340‐345)     

Association of TOMM40 Polymorphisms with Late-Onset Alzheimer’s Disease in a Northern Han Chinese Population

Mitochondrial dysfunction is an early defect in the pathogenesis of late-onset Alzheimer’s disease (LOAD). One interesting candidate gene for mitochondrial dysfunction in LOAD is the translocase of outer mitochondrial membrane 40 homolog (TOMM40) gene. Several single nucleotide polymorphisms (SNPs) within TOMM40 have been shown to affect susceptibility to LOAD in Caucasians, while there are no studies on the association of the polymorphisms with LOAD risk in Han Chinese. Here, the association of TOMM40 polymorphisms in LOAD was investigated in a large Northern Han Chinese cohort consisting of 1,578 individuals. Both allelic and genotypic associations of three SNPs (rs157580, rs2075650, and rs11556505) with LOAD risk were observed in the total sample as well as in the non- APOE ε4 carriers. For rs1160985, the allele and genotype frequencies differed significantly only in APOE ε4 carriers. After adjustment for age, gender, and APOE ε4 status, the association remained statistically significant only for the rs157580 but not for rs2075650 and rs11556505. In contrast, the rs1160985 exhibited significant risk effect after adjustment. In addition, haplotype analysis confirmed that the haplotypes derived from SNPs in rs2075650, rs11556505, and rs1160985 were associated with either risk or protective effects. In summary, our findings suggest that the TOMM40 polymorphisms may play a role in the pathogenesis of LOAD in Han Chinese.     

Decreased frontal lobe function in people with Internet addiction disorder

In our previous studies, we showed that frontal lobe and brainstem functions were abnormal in online game addicts. In this study, 14 students with Internet addiction disorder and 14 matched healthy controls underwent proton-magnetic resonance spectroscopy to measure cerebral function. Results demonstrated that the ratio of N-acetylaspartate to creatine decreased, but the ratio of cho- line-containing compounds to creatine increased in the bilateral frontal lobe white matter in people with Internet addiction disorder. However, these ratios were mostly unaltered in the brainstem, suggesting that frontal lobe function decreases in people with Internet addiction disorder.