Objective:To discuss the suitable concentration of D-galactose(D-gal)and modeling period,and establish its induced aging-related cognitive dysfunction model in the mice,and perform a comprehensive evaluation.Methods:Fifty C57BL/6J mice were randomly divided into control group and 100,200,400,and 800 mg·kg-1 D-gal groups,with 10 mice in each group.The mice in various D-gal groups were subcutaneously injected with the corresponding concentration of D-gal once daily;the mice in control group were injected with an equal volume of normal saline.The body mass and water consumption of the mice in various groups were monitored;forelimb grip strength test and experiment on the ability of pole climbing sports were used to evaluate the motor coordination ability of the mice in various groups;novel object recognition test,Y maze test,and Morris water maze test were used to evaluate the cognitive function of the mice in various groups;HE staining and Nissl staining were used to observe the pathomorphology of brain tissue of the mice in various groups;immunohistochemistry method was used to detect the expression of β-galactosidase(β-gal)protein in brain tissue of the mice in various groups;real-time fluorescence quantitative PCR(RT-qPCR)method was used to detect the mRNA expression levels of interleukin(IL)-1β,tumor necrosis factor-α(TNF-α),IL-18,and IL-4 in hippocampus tissue of the mice in various groups;Western blotting method was used to detect the expression levels of β-gal,p53,and p16 proteins in hippocampus tissue of the mice in various groups.Results:The body mass growth trends of the mice in control group and various D-gal groups were consistent and there was no statistically significant difference(P>0.05),and there was no statistically significant difference in water consumption(P>0.05).After 8 weeks of subcutaneous injection of D-gal,compared with control group,the forelimb grip strength values of the mice in 200 and 400 mg·kg?1 D-gal groups were significantly decreased(P<0.05 or P<0.01);the pole-climbing time of the mice in 200 mg·kg?1 D-gal group was significantly prolonged(P<0.05);the recognition indexes of the mice in 200 and 400 mg·kg?1 D-gal groups were significantly decreased(P<0.01);the spontaneous alternation rate of the mice in 100,200,400,and 800 mg·kg?1 D-gal group was significantly decreased(P<0.05 or P<0.01),the escape latency was significantly increased(P<0.05).Spatial probe test showed that compared with control group,the escape latency of the mice in 200 mg·kg?1 D-gal group was significantly increased(P<0.05).The HE staining and Nissl staining results showed that compared with control group,the hippocampus neurons of the mice in 200 mg·kg-1 D-gal group were arranged disorderly,with obvious nuclear pyknosis,nuclear condensation,and abnormal morphology and structure,and the number of Nissl staining positive cells was significantly decreased.The immunohistochemistry results showed that compared with control group,the β-gal expressions in CA1 region,CA3 region,and cortex region of hippocampus tissue of the mice in 200 mg·kg?1 D-gal group were strongly positive.The RT-qPCR results showed that compared with control group,the expression levels of IL-1β,IL-18,and TNF-α mRNA in hippocampus tissue of the mice in 200 mg·kg?1 D-gal group were significantly increased(P<0.05 or P<0.01),and the expression level of IL-4 mRNA was significantly decreased(P<0.01).The Western blotting results showed that compared with control group,the expression levels of β-gal,p53,and p16 proteins in hippocampus tissue of the mice in 200 mg·kg?1 D-gal group were significantly increased(P<0.05 or P<0.01).Conclusion:The aging-related cognitive dysfunction model in the mice can be established by subcutaneous injection of 200 mg·kg?1 D-gal daily for 8 weeks.

Background: and Purpose Intracranial vertebrobasilar atherosclerotic stenosis (IVBAS) is a major cause of posterior circulation stroke. Some patients suffer from stroke recurrence despite receiving medical treatment. This study aimed to determine the prognostic value of a new score for the posterior communicating artery and the P1 segment of the posterior cerebral artery (PCoA-P1) for predicting stroke recurrence in IVBAS. Methods: We retrospectively enrolled patients with severe IVBAS (70%–99%). According to the number of stroke recurrences, patients were divided into no-recurrence, single-recurrence, and multiple-recurrences groups. We developed a new 5-point grading scale, with the PCoA-P1 score ranging from 0 to 4 based on magnetic resonance angiography, in which primary collaterals were dichotomized into good (2–4 points) and poor (0 or 1 point). Stroke recurrences after the index stroke were recorded. Patients who did not experience stroke recurrence were compared with those who experienced single or multiple stroke recurrences. Results: From January 2012 to December 2019, 176 patients were enrolled, of which 116 (65.9%) had no stroke recurrence, 35 (19.9%) had a single stroke recurrence, and 25 (14.2%) had multiple stroke recurrences. Patients with single stroke recurrence (odds ratio [OR]= 4.134, 95% confidence interval [CI]=1.822–9.380, p=0.001) and multiple stroke recurrences (OR=6.894, 95% CI=2.489–19.092, p<0.001) were more likely to have poor primary collaterals than those with no stroke recurrence. Conclusions The new PCoA-P1 score appears to provide improve predictions of stroke recurrence in patients with IVBAS.

Objective To observe auditory brainstem response evoked at different electrode positions adopting electrode slices .Methods The ABRs of 12 normal guinea pigs (24 ears)were recorded by two methods using clicks as stimulation .Active electrode was positioned at the vertex while the ground electrode at the nose .The reference e‐lectrode was placed on bilateral pinnas or mastoids .Then observe waveforms ,response thresholds (RT) ,peak la‐tencies(PL) and inter-peak latencies (IPL)of ABR .Results No significant difference were observed in the RT ,Ⅰ ,Ⅱand Ⅲ PL ,Ⅰ - Ⅲ IPL of ABR between the two methods(P>0 .05) .When stimulation was decreasing and with the reference electrode slices placed at bilateral pinnas ,waveⅡpeak was stable and discernable of ABR record‐ings across twenty -four ears of guinea pigs .The amplitude decreased more slowly than any other waves ,and dis‐appeared at the last .While reference electrode slices were placed on bilateral mastoids ,the amplitude of wave Ⅲ de‐creased more slowly than any other waves except wave Ⅳ ,and disappeared at lost .Ⅱ - Ⅲ ,Ⅲ - Ⅳ IPL became shorter .These two positions both recorded amplitude higher and PL advanced for wave Ⅳ as the stimulation de‐creased by 20 to 40 dB nHL ,and Ⅲ - Ⅳ IPL became shorter .This phenomenon was more obvious when reference electrode was placed at mastoid .Conclusion Wave Ⅱwas more stable and discernible with reference electrode placed at the bilateral pinnas .Therefore wave Ⅱ recorded by this way can be a new method to record the ABR threshold of g uinea pig s .