Research on changes in cognitive function, ß-amyloid peptide and neurotrophic factor in stroke patients.

OBJECTIVE: To investigate the changes as well as the related mechanism in cognitive function and levels of serum ß-amyloid peptide (Aß) and brain-derived neurotrophic factor (BDNF) in stroke patients. PATIENTS AND METHODS: A total of 30 patients with acute stroke treated in our hospital from June 2015 to September 2016 were selected as stroke group, while 30 volunteers during the same period were enrolled as control group. Changes in cognitive function of patients were evaluated using the Montreal Cognitive Assessment (MoCA) and mini-mental state examination (MMSE) before and after the treatment. At the same time, the concentrations of serum Aß1-40 and BDNF were detected, and their correlations with the MMSE score were analyzed. Finally, levels of serum cyclic adenosine monophosphate (cAMP) and phosphorylated-cAMP-response element binding protein (p-CREB), and the phosphorylation level of Tau protein were detected by Western blotting. RESULTS: MoCA and MMSE scores of patients in stroke group were significantly lower than those in control group (p < 0.01), and the scores were significantly higher in stroke patients after treatment than those before treatment (p < 0.01). Compared with those in control group, the serum Aß1-40 concentration in patients in stroke group was significantly increased (p < 0.01), but the BDNF level was significantly decreased (p < 0.01). Compared with those before treatment, the serum Aß1-40 concentration in patients was significantly decreased after treatment (p < 0.01), but the BDNF concentration was significantly increased (p < 0.01). Correlation analysis showed that the MMSE score was negatively correlated with the concentration of Aß1-40 (r2 = 0.764, p < 0.01), but positively related to the level of BDNF (r2 = 0.827, p < 0.01). Compared with those in control group, the content of serum cAMP and p-CREB in stroke patients was significantly decreased (p < 0.01), but the expression of p-Tau was statistically increased (p < 0.01). CONCLUSIONS: The cognitive function in stroke patients is impaired, with the rising content of serum Aß1-40 and reduction of BDNF, the mechanism of which is related to the decrease of cAMP and p-CREB and the increase of p-Tau. This provides a theoretical basis for searching the new therapeutic targets and new drugs for stroke.

Epidemiological identification of Chinese individuals putatively susceptible or insusceptible to Schistosoma japonicum: a prelude to immunogenetic study of human resistance to Asian schistosomiasis.

An epidemiological method, field-tested in Hunan, China, to identify residents potentially susceptible or insusceptible to endemic schistosomiasis japonica is described, as a prelude to selection of subjects for immunogenetic studies. After an initial cross-sectional survey on two islands (Qingshan and Niangashan--population 2990) in 1995-1996, an informative cohort (N = 249) was selected for treatment and 9-month follow-up to measure exposure and re-infection. Both the population prevalence (15.8%) and the geometric mean intensity of infection (26.2 eggs/g faces) indicated that the islands were moderately endemic for schistosomiasis. Exposure measurements revealed a strong, positive, linear association (r = 0.70) between daily activity diaries and direct water-contact observation. Individuals identified as stool-positive for schistosomiasis had significantly more water contact than those who were egg-negative (P = 0.03). Almost all (93%) of the cohort had ultrasonographic evidence of periportal fibrosis before treatment but in only 1.2% was this fibrosis scored > 1 in terms of the stages identified by the World Health Organization. At the follow-up it was possible to classify the 249 subjects into three, distinct, exposure-infection epidemiological groups. The first group (N = 20) was susceptible to re-infection and constituted 8% of the cohort. The second group (N = 61) was apparently insusceptible to re-infection despite the continuing high levels of exposure and included 24% of the cohort. The other 68% of the cohort (N = 168) remained uninfected but were at most only moderately exposed, or had a status indeterminate due to non-compliance. This epidemiological identification of susceptibles and insusceptibles for schistosomiasis japonica' links field and ongoing laboratory studies aimed at characterising the genetic and immunological factors associated with resistance to re-infection and/or disease.