[Epidemiological characteristics and spatial aggregation of acute myocardial infarction in Shandong Province].

Objective: To understand the characteristics and trends of acute myocardial infarction (AMI) in Shandong Province and to provide evidence for formulating prevention and control strategies. Methods: Data were derived from the AMI incidence reports of Shandong Province's Chronic Disease Surveillance Information Management System in 2012-2021. The crude and standardized incidence rates were used as indicators to describe the incidence level of AMI. Joinpoint regression analysis was used to analyze the trends in the incidence and age of onset over the years. The contribution of population aging to the increase in AMI incidence was assessed using the rate difference decomposition method. The incidence of AMI in each district (county) in Shandong Province was visualized using ArcGIS 10.8 software, and global and local spatial autocorrelation analysis was performed using DeoDa 1.12 software. Results: From 2012 to 2021, 198 233 cases of AMI were reported from 19 provincial monitoring sites in Shandong Province, of which 53.13% were males and 97.12% were ≥45 years old. The reported crude incidence increased from 90.12 per 100 000 in 2012 to 176.54 per 100 000 in 2021, with an average annual increase of 7.01% (Z=7.35, P<0.001). There was no significant upward trend in standardized incidence (Z=1.64, P=0.140), but the standardized incidence of male residents showed an increasing trend (Z=2.76, P=0.028). Before 2014, the reported crude incidence of males was similar to that of females, but after 2014, the reported crude incidence of males was continuously higher than that of females. However, males' standardized incidence was higher than females in all years. Both crude and standardized incidence rates were higher in rural residents than in urban areas. The median onset of AMI increased from 71.6 years old in 2012 to 73.5 years old in 2021. The median age of onset in males was lower than that in females in all years, and in most years, the median age of onset in urban residents was lower than that in rural residents. The incidence of AMI in males showed a trend in younger age groups. According to the seasonal decomposition, the incidence peak of AMI was in January, and the trough was in September. The contribution of aging population to the increase in crude incidence of AMI increased from 8.63% in 2013 to 52.58% in 2021. The global spatial autocorrelation analysis showed that the incidence of AMI presented an obvious spatial clustering distribution. Local spatial autocorrelation analysis found that the high-incidence areas (counties) were mainly concentrated in Liaocheng City and Dezhou City in the northwest region of Shandong Province and Heze City in the southwest. Conclusions: The incidence of AMI among residents in Shandong Province was rising, with spatial clustering and seasonal clustering characteristics. People aged 45 years and older, male residents, and rural residents were at high risk of developing AMI. There was a certain trend of younger age at onset among men. Targeted prevention and control measures should be taken for high-incidence seasons, high-risk groups, and high-incidence clustering areas in northwestern Shandong Province.

GM1 improves neurofascin155 association with lipid rafts and prevents rat brain myelin injury after hypoxia-ischemia

White matter injury characterized by damage to myelin is an important process in hypoxic-ischemic brain damage (HIBD). Because the oligodendrocyte-specific isoform of neurofascin, neurofascin 155 (NF155), and its association with lipid rafts are essential for the establishment and stabilization of the paranodal junction, which is required for tight interaction between myelin and axons, we analyzed the effect of monosialotetrahexosyl ganglioside (GM1) on NF155 expression and its association with lipid rafts after HIBD in Sprague-Dawley rats, weighing 12-15 g, on day 7 post-partum (P7; N = 20 per group). HIBD was induced on P7 and the rats were divided into two groups: one group received an intraperitoneal injection of 50 mg/kg GM1 three times and the other group an injection of saline. There was also a group of 20 sham-operated rats. After sacrifice, the brains of the rats were removed on P30 and studied by immunochemistry, SDS-PAGE, Western blot analysis, and electron microscopy. Staining showed that the saline group had definite rarefaction and fragmentation of brain myelin sheaths, whereas the GM1 group had no obvious structural changes. The GM1 group had 1.9-2.9-fold more GM1 in lipid rafts than the saline group (fraction 3-6; all P < 0.05) and 0.5-2.4-fold higher expression of NF155 in lipid rafts (fraction 3-5; all P < 0.05). Injection of GM1 increased the content of GM1 in lipid rafts as well as NF155 expression and its lipid raft association in HIBD rat brains. GM1 may repair the structure of lipid rafts, promote the association of NF155 (or other important proteins) with lipid rafts, stabilize the structure of paranodes, and eventually prevent myelin sheath damage, suggesting a novel mechanism for its neuroprotective properties.