ABSTRACT. We aimed to evaluate the effect of melatonin on myocardial cell oncosis in the myocardial ischemia/reperfusion injury rat, and the role of the mitochondrial permeability transition pore (MPTP) therein. Sprague Dawley rats (N = 60) were randomly divided into five groups of 12 rats each: control, ischemia/reperfusion (I/R), melatonin treatment (MT), melatonin treatment + atractyloside (MT+ATR), and atractyloside (ATR). We prepared the myocardial ischemia/reperfusion model by reperfusion after the left anterior descending coronary artery was ligated for 30 min. The MT rats were given a 10 mg/kg MT intravenous injection immediately thereafter; the MT+ATR rats were also given a 5 mg/kg ATR intravenous injection 15 min before the ischemia; the ATR rats were given the ATR injection only. After 2-h reperfusion, myocardial tissue was extracted, the infarction size was determined, and myocardial ultrastructures were observed using electron microscopy. The expression level of the pre-oncosis receptor (porimin), which can induce membrane injury, was determined by western blot; the nicotinamide adenine dinucleotide (NAD + ) content was determined spectrophotometrically. The four treatment groups showed upregulated expression of myocardial porimin, increased myocardial infarction size, and reduced NAD + content (P < 0.05). Compared with the I/R and MT+ATR groups, MT rats showed downregulated expression of myocardial porimin, reduced myocardial infarct size, and increased myocardial cell NAD + content (P < 0.05). The above indices between the ATR and MT+ATR groups were not significantly different (P > 0.05). Thus, MT might protect myocardial ischemia/reperfusion rats by inhibiting MPTP opening and reducing myocardial cell oncosis.

ABSTRACT. This study aimed to evaluate the clinical significance of diffusion tensor imaging (DTI) in the early diagnosis of pyramidal tract Wallerian degeneration (WD) and assessment of neurological recovery following cerebral infarction. This study included 23 patients with acute cerebral infarction and 10 healthy adult controls. All participants underwent both magnetic resonance imaging (MRI) and DTI scans. DTI images were analyzed using the Functional MRI of the Brain Software Library to determine the regions of interest (ROI) and obtain the mean diffusivity (MD) and fractional anisotropy (FA) value for each ROI. The correlation between FA or MD and postinfarction functional recovery of the nervous system was further analyzed to assess the feasibility of using a DTI scan in the evaluation of functional recovery of the nervous system in patients with cerebral infarction. DTI may be useful in detecting signals of early postinfarction pyramidal tract WD and is useful for the evaluation of postinfarction neurological recovery. Cerebral lesions were detected using MRI in all patients. It was found that in some patients, the FA value of the ipsilateral pyramidal tract on DTI was decreased as early as day 3 after the onset of infarction and in all patients by day 7. Subsequent correlation studies showed that the FA value of the ipsilateral pyramidal tract on day 13 was negatively correlated with the National Institutes of Health Stroke Scale score, but positively correlated with the Barthel Index, motricity index, and modified Rankin Scale scores.