Environmental life cycle assessment of monosodium glutamate production in China: Based on the progress of cleaner production in recent ten years.

China is the world's leading producer of the flavor-enhancer monosodium glutamate (MSG), which is mainly produced by maize starch fermentation. Four typical scenarios (Scenario 1-Scenario 4) of MSG production from 2008 to 2019 in China were established for life cycle environmental impact assessment. Values for five midpoint environmental impact categories [primary energy demand (PED), resource depletion-water use (WU), global warming potential (GWP), acidification potential (AP), and eutrophication potential (EP)] were calculated with eFootprint based on data collected in China. The environmental impacts of producing 1 t of MSG in China in terms of PED, WU, GWP, AP, and EP were 52,800 MJ, 169,000 kg, 4590 kg CO2 eq, 42.1 kg SO2 eq, and 6.35 kg PO43- eq, respectively, in 2019. The life cycle of MSG from cradle to gate includes maize cultivation (high WU values), and the MSG production process (high PED, GWP, AP, and EP values). The normalization results of environmental impacts significantly decreased from S1 to S4 with the improvement in cleaner production in recent ten years. Sensitivity and uncertainty analyses identified steam for MSG production, irrigation water, and ammonia volatilization during maize growth as the three main factors affecting the environment. There were obvious differences in calculated environmental impacts depending on the maize cultivation data source; i.e., data from the Ecoinvent 3.1 database, or collected data for the maize-wheat rotation system in north China or the maize monoculture system in northeastern China. This demonstrates the importance of collecting local data rather than applying database from other world regions. Compared with the use of coal and natural gas, the use of biogas to produce steam had much lower PED, WU, and GWP. Which types of alternative energy to use and the replacement ratio should be based on the actual resource reserves in each region.

Effect of Tetramethylpyrazine on Neuroplasticity after Transient Focal Cerebral Ischemia Reperfusion in Rats.

Tetramethylpyrazine (TMP) has been widely used in ischemic stroke in China. The regulation of neuroplasticity may underlie the recovery of some neurological functions in ischemic stroke. Middle cerebral artery occlusion (MCAO) model was established in this study. Rats were divided into three groups: sham group, model group, and TMP group. The neurological function was evaluated using modified neurological severity score (mNSS). Following the neurological function test, expression of synaptophysin (SYP) and growth-associated protein 43 (GAP-43) were analyzed through immunohistochemistry at 3 d, 7 d, 14 d, and 28 d after MCAO. Finally, the synaptic structural plasticity was investigated using transmission electron microscopy (TEM). The TMP group showed better neurological function comparing to the model group. SYP levels increased gradually in ischemic penumbra (IP) in the model group and could be enhanced by TMP treatment at 7 d, 14 d, and 28 d, whereas GAP-43 levels increased from 3 d to 7 d and thereafter decreased gradually from 14 d to 28 d in the model group, which showed no significant improvement in the TMP group. The results of TEM showed a flatter synaptic interface, a thinner postsynaptic density (PSD), and a wider synaptic cleft in the model group, and the first two alterations could be ameliorated by TMP. Then, a Pearson's correlation test revealed mNSS markedly correlated with SYP and synaptic ultrastructures. Taken together, TMP is capable of promoting functional outcome after ischemic stroke, and the mechanisms may be partially associated with regulation of neuroplasticity.

Association Between MicroRNAs Polymorphisms and Risk of Ischemic Stroke: A Meta-Analysis in Chinese Individuals.

Objective: Previous studies have demonstrated that some single-nucleotide polymorphisms (SNPs) in miRNAs are related to the risk of ischemic stroke (IS), but the conclusions are still controversial and inconclusive. We performed this meta-analysis to further assess the association between miR-146a C>G (rs2910164), miR-149 T>C (rs2292832), miR-196a2 T>C (rs11614913), miR-499 A>G (rs3746444) and risk of IS in Chinese individuals. Methods: Relevant studies were identified in the databases of PubMed, Embase. The strength of correlation between microRNAs polymorphisms and IS risk was assessed by odds ratios (ORs) and 95% confidence intervals (95% CIs) under five genetic models. Results: 5 studies, containing 2,632 cases and 3,191 controls, were included in this meta-analysis. The overall results of meta-analysis indicated that there were no significant association between miR-146a C>G (rs2910164), miR-149 T>C (rs2292832), miR-196a2 T>C (rs11614913), and the IS risk in the overall analyses. MiR-499 A>G (rs3746444) was associated with an increased IS risk under allele model (OR = 1.30, 95% CI = 1.02-1.66), heterozygous model (OR = 1.35, 95% CI = 1.01-1.79) and dominant model (OR = 1.36, 95% CI = 1.02-1.80) in Chinese. The sensitivity analysis results of these four polymorphisms were similar to the overall results. Conclusion: MiR-499 A>G (rs3746444) G allele and AG, AG + AA genotype might be risk factors of IS in Chinese. No significant association was observed between miR-146a C>G (rs2910164), miR-149 T>C (rs2292832), miR-196a2 T>C (rs11614913), and IS risk. The associations may be different due to geographical factors of China. More explorations in more diverse geographically regions with large sample size are expected to further verify the findings in the future.