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Arbuscular mycorrhizal (AM) fungi play an important role in plant nutrient absorption and stress resistance. AM fungal spore-associated bacteria are essential for mycorrhizal colonization, but their responses to environmental changes remain largely unknown. We collected surface soil samples from a Chinese fir plantation in both summer and winter to investigate the responses of AM fungal morphological traits and spore-associated bacterial communities to simulated nitrogen deposition (40 kg N·hm -2 ·a -1 addition) and drought (-50% precipitation exclusion). Our results showed that nitrogen addition and precipitation exclusion significantly affected AM fungal spore density and extraradical hyphal length, respectively. AM fungal intraradical colonization rate, extraradical hyphal length and spore density were significantly differed between the two seasons. Compared to control (no nitrogen addition and no precipitation exclusion treatment), both nitrogen addition and precipitation exclusion significantly reduced spore density in winter, while precipitation exclusion alone and the combined nitrogen addition and precipitation exclusion significantly increased extraradical hyphal length in summer. The dominant spore-associated bacterial phyla were Proteobacteria, Acidobacteria, Actinobacteria, Chloroflexi, and Planctomycetes. Nitrogen addition and precipitation exclusion did not affect the diversity of spore-associated bacteria. However, the combined nitrogen addition and precipitation exclusion treatment altered the composition of the bacterial community, with significant variations between the two seasons. The spore-associated bacterial diversity was significantly higher and community variability (or turnover) was lower during summer than winter. Soil total nitrogen, nitrate nitrogen and dissolved organic carbon were important factors influencing the bacterial community composition. In all, the effects of nitrogen addition and precipitation exclusion on the morphological traits of AM fungi are seasonally dependent. The combination of nitrogen addition and precipitation exclusion has a significant impact on AM fungal spore-associated bacterial community structure.

Objective: To analyze the outcomes of pregnancies in women with systemic lupus erythematosus (SLE) and the risk factors affecting the outcomes., Methods: The data of SLE patients with pregnancy admitted from October, 2006 and September, 2015 were analyzed for assessing the maternal and fetal outcomes and complications. Their risk factors affecting the outcomes of the pregnancies were analyzed., Results: The 66 SLE patients (69 pregnancies) had a mean age at SLE diagnosis of 22.9 ∓ 5.1 years with a mean duration of SLE of 4.1∓3.6 years before pregnancy. Forty-five (65.2%) of the patients received oral medication for SLE treatment during pregnancy, and 44 (63.8%) were treated with prednisone and 19 (27.5%) were treated with hydroxychloroquine. The highest SLEDAI score was 6.8∓7.4 during pregnancy. The patients with moderate-to-severe disease activity had a higher rate of fetal loss (12 [54.5%] vs 12 [25.5%]) with a significantly lower birth weight of the newborns than those with remittent or mild disease (2073.0∓ 778.7 vs 2817.8∓533.7 g, P<0.05). The patients with moderate-to-severe disease activity also had higher rates of new-onset SLE (9 [40.9%] vs 6 [12.8%]), hypertension (12 [54.5%] vs 3 [6.4%]), active lupus nephritis (22 [100%] vs 4 [8.5%]), pneumonia (5 [22.7%] vs 2 [4.3%]), and renal insufficiency (8 [36.4%] vs 2 [4.3%]) compared with patients with remittent and mild disease (P<0.05). Active lupus nephritis (OR=6.10,95%CI: 1.43-25.96) was a significant predictor of adverse outcomes of the pregnancies., Conclusion: Fetal loss and maternal complications are common in patients with SLE in relation with the disease activity. Active lupus nephritis is a predictor for poor outcomes of pregnancies in SLE patients.