RESUMO
Aim Subcortical ischemic vascular demen-tia ( SIVD ) induced by chronic hypoperfusion due to small-artery disease is a common cause of vascular de-mentia ( VaD) , which is recognized as the second most prevalent type of dementia. The aim of this study was to determine whether carnosine played a protective role in cognitive impairment induced by permanent occlu-sion of the right unilateral common carotid arteries ( rUCCAO ) in SIVD. Methods Adult male mice ( C57BL/6 strain ) were subjected to rUCCAO, and treated with carnosine or saline. Locomotor test, open field test, hot plate test, freezing test and Morris water maze were performed after rUCCAO. Results There were no differences among rUCCAO group, carnosine group and sham group for total distance traveled in lo-comotor test. In the open field test, carnosine (200, 500 mg · kg-1 ) significantly revised the decrease of latency spent in the center induced by SIVD . There were no differences between rUCCAO and sham groups for the pain threshold. In freezing test, rUCCAO in-duced a significant reduction in content memory, which was completely reversed by treatment of carnosine. In Morris water maze training trials, rUCCAO-treated mice showed prolonged escape latency in acquisition phase, carnosine ( 200, 500 mg · kg-1 ) markedly shortened the escape latency. Conclusion These data suggest that carnosine has a neuroprotective effect on cognitive impairment induced by rUCCAO in mice.
RESUMO
Genomic DNA of two fungi Thamnidium elegans and Umbelopsis isabellina were extracted with an amended Cetyltrimethyl Ammonium Bromide (CTAB) method. This modified method uses repeated freezing in liquid nitrogen and thawing with combination of shocking with glass beads to replace of the tra- ditional method. Quality and concentration of DNA extracted by the modified methodwere tested. Compared with the traditional method, higher yield and purity of genomic DNA were obtained with less amount ofmy- celium. The result indicted that this is a simple and highly efficient method, which is suitable to treat many samples at one time and for basic molecular experiments, such as restriction endonuclease reaction and PCR.