分子疫苗防治老年性痴呆小鼠模型的研究进展

老年斑是老年性痴呆(Alzheimer's disease, AD)的特征性病理改变,β-淀粉样(β-amyloid,Aβ)是其主要成分.将Aβ作为疫苗对动物进行免疫,有明显抑制转基因小鼠脑内Aβ的沉积,清除原有斑块的作用,从而减少异常Aβ沉积对认知功能的损害.疫苗没有引起针对动物自身抗原的免疫反应,对中枢神经系统的正常功能也没有明显损害.     

A remarkable new genus of leafhoppers (Hemiptera,Cicadellidae, Iassinae) from Southeast Asia

Tardrabassus pakneunensis, n. gen. & sp. is described and illustrated. The new genus shows morphological affinities to three leafhopper subfamilies, Tartessinae, Deltocephalinae, and Iassinae, but is tentatively placed in Iassinae based on the position of the ocelli, the reduced lateral frontal sutures, the leg chaetotaxy, and the structure of the male genitalia.     

A simplified diphenylamine colorimetric method for growth quantification

Cell growth needs to be monitored in biological studies and bioprocess optimization. In special circumstances, such as microbial fermentations in media containing insoluble particles, accurate cell growth quantification is a challenge with current methods. Only the Burton method is applicable in such circumstances. The original Burton method was previously simplified by adopting a two-step sample pretreatment in perchloric acid procedure to eliminate the need for DNA extraction. Here, we further simplified the Burton method by replacing the previous two-step perchloric acid pretreatment with a new and one-step diphenylamine reagent pretreatment. The reliability and accuracy of this simplified method were assessed by measuring the biomass of four model microorganisms: Escherichia coli, Streptomyces clavuligerus, Saccharomyces cerevisiae, and Trichoderma reesei grown in normal media or those containing solid particles. The results demonstrate that this new simplified method performs comparably to the conventional methods, such as OD₆₀₀ or the previously modified Burton method, and is much more sensitive than the dry weight method. Overall, the new method is simple, reliable, easy to perform, and generally applicable in most circumstances, and it reduces the operation time from more than 12 h (for the previously simplified Burton method) to about 2 h.     

Cognitive Changes during Prolonged Stay at High Altitude and Its Correlation with C-Reactive Protein

Hypersensitive C-reaction protein (hsCRP) may be a risk factor for cognitive impairment resulting from Alzheimer’s disease (AD), stroke, and vascular dementia. This study explored the correlation of peripheral blood hsCRP level with cognitive decline due to high altitude exposure. The study was conducted on 100 male military participants who had never been to high altitude. Cerebral oxygen saturation monitoring, event related potentials (P300, N200) detection, and neurocognitive assessment was performed and total hsCRP, interleukin-6 (IL-6), and homocysteine was estimated at 500m altitude, 3650m altitude, 3day, 1, and 3 month post arriving at the base camp (4400m), and 1 month after coming back to the 500m altitude. High altitude increased brain oxygen saturation, prolonged P300 and N200 latencies, injured cognitive functions, and raised plasma hsCRP levels. But they all recovered in varying degrees at 1 and 3 month post arriving at the base camp (4400m). P300 latencies and hsCRP levels were strongly correlated to cognitive performances. These results suggested that cognitive deterioration occurred during the acute period of exposure to high altitude and may recover probably owning to acclimatization after extended stay at high altitude. Plasma hsCRP is inversely correlated to neurological cognition and it may be a potential biomarker for the prediction of high altitude induced cognitive dysfunction.