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Previous studies have used sodium magnetic resonance imaging (MRI) to investigate the increase in tissue sodium concentration that occurs during a stroke by using various animal models of brain ischemia. However, most of these studies have involved rats, cats, or nonhuman primates. Although studies involving mice are relatively scant, mice have become the principal animal model for studying many human diseases, particularly in the field of genetics. Accordingly, this study employed sodium MRI to monitor changes in the intensity of sodium signals in a mouse model of ischemic stroke. The experiments were conducted using a 7-T MRI system, and a commercial double-tuned sodium/proton transmit-receive surface coil was used to capture the sodium and proton signal images. Sodium MRI was performed using a fast low-angle shot pulse sequence. The mice underwent middle cerebral artery occlusion to induce focal brain ischemia 48 h before the MRI scans were performed. The signal intensity of the sodium image was determined for a region of interest (ROI) in the ischemic area, and an ROI contralateral to this area. The average signal intensity in the sodium images of the mouse brains exhibited a 2.51-fold increase and a standard deviation was 0.93. The results of this study demonstrate the feasibility of using a 7-T MRI system to perform sodium MRI of a mouse model of ischemic stroke. The sodium signal intensity of the mouse brain revealed a substantial increase in sodium levels in the ischemic area compared with that in the contralateral brain hemisphere.

Consumption of fructose has been linked to the development of metabolic syndrome, whereas the cardiomyopathic changes and cardiac apoptosis of dietary high-fructose intake have not yet been clarified. The purpose of this study was to evaluate the effects of high-fructose on cardiac apoptotic and survival pathways. Thirty-two Wistar rats were randomly divided into a control group (CON), which received a standard chow diet, and a fructose-induced metabolic syndrome group (FIMS), which received a 50% fructose-content diet for 13 weeks. Histopathological analysis, TUNEL assays and Western blotting were performed on the excised hearts from both groups. The blood pressure, glucose, insulin, triglyceride and cholesterol levels were significantly increased in the FIMS group, compared with the CON group. The abnormal myocardial architecture, enlarged interstitial space and increased cardiac TUNEL-positive apoptotic cells were observed in the FIMS group. The TNF-α, TNF receptor 1, Fas ligand, Fas receptor, FADD, and activated caspase-3 and 8 protein levels (Fas pathway) and the Bax, Bak, Bax/Bcl-2, Bak/Bcl-xL, cytosolic cytochrome c, and activated caspase-3 and nine protein levels (mitochondria pathway) were increased in the FIMS group compared with those in the CON group. The IGFI, IGFI-R, p-PI3K, p-Akt, Bcl-2 and Bcl-xL protein levels (survival pathway) were all significantly decreased in the FIMS group compared with those in the CON group. High-fructose intake elevated blood pressure and glucose levels; moreover, high-fructose diet activated cardiac Fas-dependent and mitochondria-dependent apoptotic pathways and suppressed the survival pathway, which might provide one possible mechanism for developing heart failure in patients with metabolic syndrome.

The purpose of this study is to use sodium magnetic resonance imaging (sodium MRI) to observe the variations in sodium signal intensity in mice brains after ischemic stroke, and to estimate the tissue sodium concentration of the ischemia area in mice brain. Experiments were performed using a 7T MRI system. Before the MRI scan (48 hours), the mice underwent middle cerebral artery occlusion (MCAO) to induce focal brain ischemia. The average signal intensity in the sodium images of mice brains showed a 2.2-fold increase. The average estimated values of the ischemia area and contralateral area in the mice brains were 106.5 mM and 49.9 mM, respectively. This study demonstrates the feasibility of sodium MRI in mice brain of ischemic stroke at 7T MRI. The signal intensity of sodium on the mice brain shows a significant increase in the ischemia area compared to the contralateral brain hemisphere. The estimated values of the sodium concentration exhibited a significant correlation with the biochemical values of the sodium concentrations.

This study investigated the efficiency of heavy metal separation and recovery in electrostatic precipitator (ESP) ash from a municipal solid waste incinerator (MSWI) when carbon dioxide is used as the pre-extraction agent. The experiments were conducted at 120°C with pH values of 3–6 and liquid-to-solid (L/S) ratios varying from 10:1 to 40:1. The results indicate that an increase in the L/S ratio enhances the separation and recovery efficiency of heavy metals in the MSWI ash. The separation efficiency of Cd, Cr, and Zn increased significantly with the increased L/S ratio. The pH level was the prominent factor affecting the extraction of heavy metals from ESP ash: at pH 3–4, maximum amounts of Cd and Cr were extracted. However, due to the increased release of ions with increased CO3 2−, Zn was relatively soluble at high pH values. In cases with an L/S ratio of 40:1 and pH 3, the Cd, Cr, and Cu extraction amounts were 86.4%, 71.2%, and 34.9%, respectively. Pb and its compounds remained in a stable state und...

Sodium is one of the essential indicators of cell viability in vivo. Regarding extant literature, sodium MRI is widely employed for various studies, including research on tumors, strokes, and neurocognition, because it can non-invasively provide data of physiological metabolism in vivo. Currently, strokes are among the 3 leading causes of death worldwide, and can be categorized as hemorrhagic or ischemic. Approximately 70% to 80% of stroke patients experience an ischemic stroke. Although numerous relevant studies have focused on larger animal models, such as rats, cats, and nonhuman primates, literature that employs mice experimental models is scarce. In this study, we conducted sodium MRI on the brains of mice after an ischemic stroke to observe sodium signal variations in the brain following this type of stroke. The findings indicated that the sodium signals in the brain regions affected by stroke were 2.3 times stronger than those in the lateral ventricles.