[Pollution Characteristics of Microplastics in Migratory Bird Habitats Located Within Poyang Lake Wetlands].

Microplastic pollution (plastics with particle sizes<5 mm) has become a serious problem. In this study, we sampled the surface water, sediment, and bird excrement from the shore, center of the lake, and active areas for birds in Baisha Lake, which is key habitat for migratory birds in the Poyang Lake wetlands. The microplastics were separated by flotation separation, and then, we analyzed the pollution characteristics of this area. The main results were as follows. ① There were significant differences in the abundance of microplastics in water and sediment at different sampling points in the study area. The average abundance of microplastics in water and sediment were 263.28 per·m-3 and 215.9 per·kg-1, respectively. The average abundance of microplastics in migratory bird feces was 4.93 per·g-1. ② There were four kinds of microplastics in the surface water in terms of the different morphologies of particles, namely, pellets, films, fragments, and fibers, among which pellets were the major type. The main colors of microplastics were red, yellow, green, blue, purple, black, and transparent. The rank in terms of the size of microplastics was follows: < 1 mm > 1-2 mm > 2-3 mm > 3-5 mm, and the abundance decreased with the increase of particle size. ③ There were also four kinds of microplastics with different morphologies in the sediment, namely, pellets, films, fragments, and fibers. The main colors of these microplastics were red, yellow, blue, purple, black, and transparent. Microplastic sizes on the shore of the lake and bird habitat were mainly < 1 mm, and 1-2 mm particles were mainly detected in the center of the lake. ④ There were four types of microplastics in the excrement of migratory birds, namely, pellets, films, fragments, and fibers. The colors of these microplastics were red, yellow, green, purple, and transparent, and the particle size was mainly < 1 mm. ⑤ There was no consistency in the types of microplastics in the water body, sediment, and bird droppings. However, the size distribution for water and bird excrement was consistent. The results indicate that Poyang Lake bird habitat is polluted by microplastics, and the birds are inevitably exposed to microplastics. This study warns that microplastics will be an emerging threat to migratory birds.

[Platelet-rich plasma combined with demineralized freeze-dried bone allografts for periodontal regeneration in the treatment of periodontal defects: a meta-analysis].

PURPOSE: The aim of this meta analysis was to assess the influence of platelet-rich plasma (PRP)combined with demineralized freeze-dried bone allografts(DFDBA) on regeneration of periodontal periodontal defects by means of evaluating clinical and radiographic outcomes in prospective human clinical trials. METHODS: The following databases such as PubMed, The Cochrane Library, EMbase, CNKI, Wanfang data and VIP data were searched on computer from inception to December, 2016. According to the inclusion and exclusion criteria, two reviewers independently extracted the data，assessed the methodological quality of the included studies. RevMan 5.2 was applied for meta analysis. RESULTS: Six papers were obtained reviewed which included 205 periodontal bone defect sites. Six articles showed that there was no significant difference in probing depth decrease between PRP combined with DFDBA and PRP or DFBDA group[MD=0.35, 95%CI（-0.09，0.79), P=0.12], but there was significant difference in clinical attachment loss increase between the two groups［MD= 0.68，95%CI（0.41，0.94），P<0.00001]. Three articles were included for evaluating bone filling, there was significant difference in the distance from the cemento-enamel junction(CEJ) to the vertical bone defect(BD)(CEJ-BD)[MD=0.71，95%CI（0.46，0.95），P<0.00001]between the two groups; there was also significant difference in the distance from the alveolar crest to the vertical bone defect(AC-BD)[MD=0.64，95%CI（0.41，0.87)，P<0.00001]between the two groups. but there was no significant difference in the distance from the cemento-enamel junction(CEJ)to the alveolar crest (AC)(CEJ-AC)[MD=0.03，95%CI（-0.10，0.16），P=0.68] between the two groups. CONCLUSIONS: Within the limitations of this meta analysis, PRP combined with DFDBA is superior to PRP or DFDBA alone in clinical attachment loss and bone filling ,but there was no significant difference in probing depth. However, given the limited sample size and quantity of included studies, the above findings still need to be further proved by conducting more high-quality and large-scale RCTs.