Background and purpose: A recently proposed pre-dementia syndrome, motoric cognitive risk (MCR) syndrome, is characterized by cognitive complaints and slow gait, and increases the risk of dementia and mortality. The aim of the present study was to explore the prevalence of and factors associated with MCR syndrome in elderly community-dwelling Chinese subjects. Methods: The Ningbo Community Study on Aging recruited 953 Chinese community-dwelling participants aged ≥ 65 years from November 2016 to March 2017. Handgrip, Five-Times-Sit-to-Stand (FTSS) test time and body composition, as well as comprehensive geriatric evaluation, were measured as potentially independent factors associated with MCR syndrome. Results: The prevalence of MCR syndrome was 12.8% in men and 12.6% in women, and high prevalence of MCR syndrome was not associated with age or sex. Multiple logistic regression analysis by sex showed that a 1-SD increase in FTSS test time in males and females was associated with 45% (95% confidence intervals, 19-76; P < 0.01) and 20% (95% confidence intervals, 9-33; P < 0.01) higher risk of having MCR syndrome, respectively, whereas handgrip strength was inversely correlated with MCR syndrome in males [odds ratio (OR), 0.91; P = 0.02] but not females (P = 0.06). Moreover, the relationship of arm fat mass and MCR syndrome was statistically significant in both sexes (OR, 1.69-1.77), but leg fat mass was only associated with MCR syndrome (OR, 1.56; P = 0.02) in men. Conclusions: Handgrip, FTSS test time and body composition were associated in a sex-specific manner with MCR syndrome in elderly community-dwelling Chinese subjects. Our results on MCR syndrome are novel and should be considered as important information in future studies.

Three-month-old seedlings of Lycoris chinensis were treated with biotic and abiotic elicitors: yeast elicitor (YE), methyl jasmonate (MJ), salicylic acid (SA), and sodium nitroprusside as NO donator (NO). We have shown that the addition of MJ and NO promotes the accumulation of galanthamine in these seedlings. The effect of these elicitors on the growth of the seedlings, as well as on the amount of the alkaloids accumulated in the seedlings was studied. The results showed that, in general, high doses of MJ and SA had a negative effect on the growth of the seedlings, while appropriate doses of NO and YE had a positive effect on the growth of the seedlings. It was remarkable that the addition of MJ, NO, and YE can promote galanthamine accumulation in seedlings. The accumulation was higher in treatments at higher concentrations of NO (100 µM), where the release of galanthamine was 1.72-fold higher than that of the control at the 10 th day of culture. The highest values of lycorine were obtained in seedlings treated with YE at a concentration of 0.01 g/l and by the 10 th day of culture; the level was 1.38 times of the control.

Pine wilt disease (PWD) is a deadly disease to pines (Pinus spp.) worldwide. The occurrence of PWD can reduce the relative abundance of root ectomycorrhizal fungi (ECMF) and dark septate endophytes (DSE). However, the effects of exogenous ECMF/DSE inoculation on the rhizosphere microbial community structure of Pinus tabulaeformis infected by pine wood nematode (PWN) is little known. Here, we tested how ECMF/DSE may improve resistance to PWD by quantifying microbial carbon biomass and soil enzymatic activity among different treatments at 6 and 9 months after PWN infection. Denaturing gradient gel electrophoresis (DGGE) was used to study the microbial community structure at 3, 6, and 9 months after PWN infection in the rhizosphere of P. tabulaeformis seedlings inoculated with ECMF/DSE. The results showed that exogenous ECMF/DSE inoculation reduced the disease severity caused by PWN infection. After PWN infection, the rhizosphere microbial carbon of seedlings inoculated with Amanita vaginata, Suillus bovinus, Gaeumannomyces cylindrosporus, and Paraphoma chrysanthemicola was 38.16, 49.67, 42.11, and 96.05% higher than that of the control group, respectively. Inoculation of ECMF/DSE inhibited the decrease of rhizosphere microbial biomass caused by PWN infection. The richness and diversity of P. tabulaeformis rhizosphere fungi at 9 months were reduced by PWN infection but partially recovered by the exogenous fungi (ECMF/DSE) inoculation except for P. chrysanthemicola, which indicates a role of ECMF/DSE in maintaining stability of the microbial community. Inoculation with ECMF/DSE increased the beneficial bacterial (Thauera sp., Mesorhizobium sp., etc.) and fungal groups (Tomentella ellisii, Wilcoxina mikolae, etc.) of in the rhizosphere. In summary, exogenous ECMF/DSE inoculation could increase P. tabulaeformis resistance to PWD probably by improving the rhizosphere microenvironment.

The nematophagous fungus Esteya vermicola has tremendous potential for biological control. This species exhibits strong infectious activity against pinewood nematodes, whereas the study on the effect of nutrition and environmental factors is still of paucity. Carbon (C), nitrogen (N), pH value, temperature, and water activity have great impact on the fungal growth, sporulation, and germination. In nutrition study, the greatest number of conidia (2.36 × 10(9) per colony) was obtained at the C:N ratio of 100:1 with a carbon concentration 32 g l(-1). In addition, the germination rate and radial growth of E. vermicola were used to evaluate the effects of environmental conditions and they were optimized as following: pH 5.5, 26 °C and water activity of 0.98. Our results also confirmed that variation of environmental factors has a detrimental influence on the efficacy of active conidia and growth of fungus. Moreover, under above optimal condition, the biocontrol efficacy was significantly improved in regard to the increase of adhesive and mortality rate, which highlight the study on the application of E. vermicola as pine wilt disease biocontrol agent.

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