Inhibition of Delayed Cerebral Ischemia by Magnesium Is Insufficient for Subarachnoid Hemorrhage Patients: A Network Meta-Analysis.

Objective: After subarachnoid hemorrhage, magnesium could reduce the incidence of delayed cerebral ischemia; however, it is still controversial. This study updated the results of recently published magnesium-related studies and conducted an exploratory analysis of the impact of application strategies and intervention factors on the results. Methods: Public databases were searched from the date of their inception to May 10, 2021. Randomized controlled trials on magnesium agent-related regimens for subarachnoid hemorrhage patients were included. Results: In total, 28 articles were included in the meta-analysis. For delayed cerebral ischemia, magnesium-related interventions significantly reduced the risk of delayed cerebral ischemia compared with nonmagnesium interventions (odds ratios: 0.40; 95% confidence interval: 0.28-0.56; p < 0.01). For cerebral vasospasm, a random effects model showed that magnesium significantly reduced the risk of cerebral vasospasm (odds ratios: 0.46; 95% confidence interval: 0.33-0.63; p < 0.01). In the subgroup analysis, intracranial magnesium (odds ratios: 6.67; 95% confidence interval: 1.14-38.83; p=0.03) and magnesium plus hydrogen (odds ratios: 10; 95% confidence interval: 1.59-62.73; p=0.01) produced significant results in improving the good recovery rate compared to the control. In the network meta-analysis, magnesium plus nimodipine and simvastatin even showed an effective trend in death/persistent vegetative status improvement. Conclusion: This study supports the beneficial effect of magnesium in reducing the risk of delayed cerebral ischemia. Based on a single randomized controlled trial, immediate intracranial magnesium therapy with intravenous hydrogen after subarachnoid hemorrhage can increase the good recovery rate. Therefore, more high-quality studies are needed to confirm this finding.

Effects of exogenous vitamin D on endoplasmic reticulum stress-related factors in the vitamin D deficiency rats with cerebral ischemia.

We observed the potential neuroprotective effect of exogenous vitamin D on cerebral ischemia in vitamin D deficiency rats and explored its mechanism. Sixty Sprague Dawley rats were randomly divided into three groups including control (CON) group, vitamin D deficiency (VDD) group and vitamin D deficiency combined with exogenous vitamin D (VDD + VD) group, with 20 rats in each group. The rats in the CON group were fed with normal diet, while the rats in the VDD and VDD + VD groups with vitamin D-deficient diet for 8 weeks, and then underwent middle cerebral artery occlusion (MCAO). Six hours later, exogenous 25-hydroxyvitaminD (25-VD3) was intravenously injected into the rats of the VDD + VD group every 24 h for 4 times. Motor behaviors were significantly better and 25-VD3 level in the left brain tissue was significantly higher in the CON group than in the VDD and VDD + VD groups 102 h after MCAO (all P < 0.05). Although the motor behaviors, infarct volume and 25-VD3 level in brain tissue showed a good tendency in the VDD + VD group as compared with VDD group, the two groups were not significantly different (all P > 0.05). GPR78 was significantly higher, but apoptosis and CHOP significantly lower in the VDD + VD group than in the VDD group (all P < 0.05). The aggravation of cerebral ischemia caused by vitamin D deficiency is possibly due to up-regulating GRP78 and down-regulating CHOP in brain tissue.

[Assessment of rice achievable productivity and its application in rice production management division: a case study in Fuyang County of Zhejiang Province, East China].

Rice productivity is the key factor affecting rice production and its sustainable development. Based on the gradation of cultivated land quality at county-level, this paper evaluated the rice productivity in Fuyang County of Zhejiang Province, and, through selected sampling field investigation and according to the land productivity index of paddy field quality, a model for assessing rice achievable productivity was established, aimed to analyze the regional rice productivity and its achievable productivity. In the study area, there was a positive correlation between the land productivity index and rice yield. For single cropping rice, its achievable productivity was 1.70 x 10(5) t, being 1.6 times of its realistic productivity (1.04 x 10(5) t). In 2009, the realistic rice productivity per unit area was 7676 kg x hm(-2), and the achievable productivity was 8831 kg x hm(-2), with a production potentiality of +15%, a big potential of rice production capacity in the county. Through the analyses of rice productivity, relative superiority of rice production scale, and its growth potential index in the villages and towns, the rice production of Fuyang County was divided into three regions, i. e., key enhancement region, optimization construction region, and development protection region.