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Objective To explore the potential application of glucans binding protein (GBP) in the detection of soluble glucans from serum sampled from patients with invasive fungal infection (IFI). Methods The prokaryotic plasmid pET30a-GBP252-668 coding for 252 to 668 amino acid in GBP as an active domain of GBP of Limulus polyphemus was constructed. The recombinant GBP252-668 was expressed and purified.Then a double GBP252-668 sandwich method was developed to detect (1,3)-β-D-glucans in the serum of patients with IFI. Meanwhile, the results were compared with G-test. Results Recombinant GBP252-668 (molecular weight is about 46 ku) was obtained and the double GBP252-668 sandwich method was established and optimized via chessboard method, the concentrations of GBP252-668 were 8 and 16 g/L for coating and detection respectively. The serum sampled from 48 patients with IFI and from 48 healthy donors were examined.and results were analysed. The sensitivity and specificity of double GBP252-668 sandwich method were 91.67% and 89.58% respectively and the sensitivity was non-inferior to G-test, and specificity of double GBP252-668 sandwich method was even higher than that of G-test (79.17%). Conclusions The GBP252-668 sandwich method is a potential detection method for IFI diagnosis. The method is non-inferior to G-test and its specificity is even higher than G-test. It is expected to be a new commercially available kit for IFI detection.

Glycyrrhiza inflata Batalin is an important medical plant of the genus Glycyrrhiza. It is one of the key protected plants in China, distributed in the desert areas of southern Xinjiang and Dunhuang of Gansu Province. It has a strong resistance to drought, heat, and salt stresses, and plays a pivotal role in sand fixtion in desert areas. In this study, based on 157 valid distribution records and eight environmental factors including climate factors and altitude, the potential distribution area of G. inflata in the last glacial maximum, middle Holocen, modern, and future (2050) times in China were predicted, using the optimized MaxEnt model and ArcGis 10.2 software. The results showed that the predicted distribution area was highly consistent with the current distribution range, and the area under the receiver operating characteristic (AUC) curve was 0.986, indicating that the prediction performance was excellent. The key climatic factors affecting the distribution were precipitation in December and the average annual precipitation. Meanwhile, the suitable area of G. inflata in modern times was 1,831,026 km2, mainly distributed in Turpan-Hami Basin, Tarim Basin, and Dunhuang of Gansu Province, with Lop Nur Town of Xinjiang as the distribution center. In 2050, the potential suitable area forG. inflata in China will be 1,808,090 km2, 250,970 km2 of which will be highly suitable, which is 150,600 km2 smaller than that in modern times, with a reduction rate of 60.0%. Therefore, there is a trend of great reduction in the suitable area of G. inflata. From the last glaciation maximum to the middle Holocene, the geographical distribution center shifted to the southwest margin of the Kumtag Desert, Xinjiang, then later continued to shift to the southwest. This study will provide a basis for understanding the origin and evolution of G. inflata, developing conservation strategies to minimize the impacts of environment change, and utilizing plant resource. [ABSTRACT FROM AUTHOR]

This study aimed to examine the responses of persistent soil seed bank to future precipitation reduction of global climate change in the forest-steppe ecotone of Hulunbuir. Samples of soil seed bank were collected from 0-10 cm soil layer along a precipitation gradient. We examined the density, species composition, diversity of seed bank and their relationship with vegetation. Structural equation model was used to explore the direct impact of annual precipitation on soil seed bank and the indirect impact through vegetation, soil nitrogen, soil phosphorus, and soil pH. The results showed that seed bank density and species richness were negatively correlated with annual precipitation. The species diversity of soil seed banks in grasslands was higher than that in forests. The similarity between soil seed bank and vegetation was generally low. The results of structural equation model showed that the effects of annual precipitation on seed bank density and species richness were negative, with the standard path coefficients of -0.051 and -0.122, respectively. The direct effect of annual precipitation on seed bank density and species richness were positive. Precipitation had indirect and positive effect on seed bank density and species richness through soil nitrogen, a significantly indirect negative effect on seed bank species richness through soil pH and soil available phosphorus, and a significantly indirect negative effect on seed bank density through soil pH. The reduction of precipitation under furture climate change might alter the hedging strategies of plants. The persistent soil seed bank in the forest-steppeecotone had a potential buffering effect against future precipitation reduction. [ABSTRACT FROM AUTHOR]

Nanophyton L. has been treated as a monotypic genus, but seven other Nanophyton species have been published based on morphological features. To examine the phylogenetic relationships between Nanophyton species, especially the similar species N. erinaceum and N. mongolicum, all species in Nanophyton except N. pulvinatum and different populations of N. erinaceum and N. mongolicum in China were sampled from herbarium specimens. Samples were analyzed based on two molecular markers (ITS and psbB‐psbH) using maximum likelihood and Bayesian inference methods. Our results provided support for the following conclusions: 1) Nanophyton is monophyletic and composed of two monophyletic clades. One clade may be recognized as N. sect. Nanophyton, but contrary to the current taxonomy it includes only N. erinaceum. The other clade represent N. sect. Montana and include all other Nanophyton species, but intragenetic variation within this clade is low. 2) Variable sites in both ITS and psbB‐psbH sequences well distinguish N. erinaceum from N. mongolicum, and samples from different populations of N. erinaceum and N. mongolicum in China formed well‐supported, distinct clades. 3) Nanophyton erinaceum is a typical Central Asian species, mainly distributed in western Siberia and Central Asia (Kazakhstan, Kyrgyzstan, Tajikistan, Mongolia and northwestern China (north Xinjiang)), while N. mongolicum is a Mongolian floristic element species mainly found from the Altai region of northern Xinjiang (China) to Mongolian Altai (Mongolia). [ABSTRACT FROM AUTHOR]

Aim: Evolutionary processes of mountain plants in arid lands remain poorly understood. Here, we investigate population genomics of the endangered wild apple tree to interpret the effects of long‐term aridification on plant diversification and demographical history in Central Asian Mountains. Location: The Tianshan Mountains, spanning north‐western China, Kazakhstan, Kyrgyzstan and Tajikistan. Taxon: Malus sieversii (Rosaceae) Methods: Using genome‐wide single nucleotide polymorphisms, we assessed genetic diversity and genetic structure of 15 populations across the species' range. Demographical history was simulated with approximate Bayesian computation and species distribution modelling. We used a general linear model to identify key environmental factors affecting population genetic diversity and structure. Results: We separated the 15 populations into three groups: the eastern group of western Junggar Mountains in China; the central group of the Ili Valley, the Talas Alatau Mountains in Kazakhstan and Kyrgyzstan; and the western group of Tajikistan and the Dzungarian Alatau in Kazakhstan. Central populations had higher genetic diversity and effective population size than eastern and western populations. The three groups split at the late Miocene and subsequently experienced extensive admixture. We detected a significant pattern of isolation by distance, but not isolation by environment, among these populations. Population genetic diversity was significantly associated with longitudinal and current environmental gradients. Main conclusions: Long‐term aridification promoted distribution fragmentation and plant lineage divergence of relict broad‐leaved forests in Central Asian Mountains. Both geographical isolation and environmental heterogeneity shaped spatial patterns in genetic variation among M. sieversii populations. To maintain genetic integrity, we propose the establishment of an international network for the conservation of this endangered wild apple tree. [ABSTRACT FROM AUTHOR]

Fruit type has a major impact on seed dispersal, seed predation and energy allocation, but our understanding of large-scale patterns in fruit type variation is weak. We used a dataset of 4008 Australian species to provide the first continental-scale tests of a series of hypotheses about the factors that might affect fruit type. We found a significant latitudinal gradient in the proportion of fleshy-fruited species, with the percentage of fleshy-fruited species rising from 19% at 43.75°S to 49% at 9.25°S. Species bearing fleshy fruits were more frequent on the coastal fringes of Australia, while species bearing non-fleshy fruits became more frequent toward the arid centre. Wet, warm and stable climates favoured fleshy-fruited species, with the two best predictors of the proportion of fleshy-fruited species being maximum precipitation over five days ( R2 = 0.40), and precipitation in the wettest month ( R2 = 0.25). These results remained consistent after accounting for phylogenetic correlation among species. A combined model including variables of precipitation, temperature, and climatic variation explained 67% of the variation in the proportion of fleshy-fruited species. Our results are consistent with the idea that plant reproductive strategies are more often tied to conditions during the parts of the year in which they grow than to conditions during the harsh parts of the year. Overall, our findings demonstrate strong relationships between plant reproductive traits and environmental gradients, and improve our understanding of the factors that shape large-scale patterns in plant ecological strategies. [ABSTRACT FROM AUTHOR]

Quaternary climatic oscillations appear to have influenced the genetic diversity and evolutionary history of arid-adapted plants. To understand the processes involved and reveal evolutionary relationships, haplotypes were examined from Calligonum roborovskii, an endemic species occurring in the arid zones across the desert regions of north-western China, and seven other species also from Calligonum section Medusa, including C. gobicum, C. mongolicum and the narrow endemic species C. ebi-nuricum, C. pumilum, C. taklimakanense, C. trifarium and C. yengisaricum. Forty-three haplotypes were identified in 422 individuals from 51 natural populations, from variation of two plastid DNA intergenic spacers ( rpl32- trnL and ycf6- psbM). A high level of total genetic diversity was found across species for which more than two populations were examined, including C. gobicum, C. mongolicum, C. pumilum and C. roborovskii. A distinct isolation-by-distance pattern in each of these species was suggested by the Mantel test, indicating that restricted gene flow caused high genetic differentiation among populations. Three haplotypes were shared by two or three species each, but the other 40 haplotypes were species-specific. The 43 haplotypes split into three major clades, but not species-specific lineages; most of the Calligonum species were not reciprocally monophyletic, probably due to incomplete lineage sorting or introgression. The identified haplotypes were dated to 1.97 Mya (95% highest posterior density: 2.95-0.99 Mya) and diverged until the late Pleistocene, possibly linked to aridification and enlargement of deserts caused by climate changes. Variation of desert habitats during the Pleistocene might play a key role in causing the divergence. [ABSTRACT FROM AUTHOR]