Amyotrophic lateral sclerosis (ALS) is a multi-system disease featured by movement disorder. Studies on ALS using static neuroimaging indexes demonstrated inconsistent results. However, recent work indicated that the intrinsic brain activity was time-varying, and the abnormal temporal dynamics of brain activity in ALS remains unknown. Resting-state functional magnetic resonance imaging data were first obtained from 54 patients with ALS and 54 healthy controls (HCs). Then the dynamic regional homogeneity (d-ReHo) was calculated and compared between the two groups. Correlation analyses between altered d-ReHo and clinical scores were further performed. Compared with HCs, ALS patients showed higher d-ReHo in the left lingual gyrus while lower d-ReHo in the left rectus gyrus and left parahippocampal gyrus. Moreover, the d-ReHo in the left lingual gyrus exhibited correlation with disease progression rate in ALS at a trend level. Our findings suggested that altered dynamics in intrinsic brain activity might be a potential biomarker for diagnosing of ALS.
Rheumatic heart disease is the most severe complication of rheumatic fever. Till date, very few successful animal models of
rheumatic valvular disease have been reported. This study aimed at developing a suitable animal model of chronic rheumatic
valvulitis for further investigation and prevention of rheumatic heart disease. Lewis rats were immunized with one administration
of formalin-killed and sonicated group A streptococci together with Complete Freund’s Adjuvant every 7 days for three cycles
followed by group A streptococci alone till killing. Control rats were administered adjuvants and saline. Rats in group 1
were killed 12 weeks after the initial injection. Rats in group 2 and control group were killed 24 weeks after the initial
injection. Results 62.5% (5/8) of rats in group 1 developed myocarditis and 50% (4/8) developed valvulitis. Histological examination
of cardiac sections showed only cellular infiltrates. In contrast, 75% (6/8) of rats in group 2 developed rheumatic-like myocarditis
and 62.5% (5/8) developed chronic valvulitis. Histological manifestations of the hearts in group 2 animals involved not only
acute damage such as cellular infiltrates, Aschoff-like cells, verrucous vegetation, but also chronic lesions such as fibrosis,
vascular neogenesis. None of the rats (0/8) in control group presented myocarditis or valvulitis. Lewis rat repeatedly immunized
with formalin-killed GAS may be a suitable animal model of chronic rheumatic valvulitis. It may be useful for future investigation
of the pathogenesis and possible preventive strategies of human rheumatic heart disease. 相似文献