Patterns and environmental drivers of C, N, and P stoichiometry in the leaf-litter-soil system associated with Mongolian pine forests.

Ecological stoichiometry is an important approach to understand plant nutrient cycling and balance in the forest ecosystem. However, understanding of stoichiometric patterns through the leaf-litter-soil system of Mongolian pine among different stand origins is still scarce. Therefore, to reveal the variations in Mongolian pine carbon (C), nitrogen (N), and phosphorus (P) stoichiometry and stoichiometric homeostasis among different stand origins, we measured C, N, and P concentrations of leaves, litter, and soil, and analyzed the nutrient resorption efficiencies of leaves in differently aged plantations and natural forests from semi-arid and dry sub-humid regions. The results showed that (1) the stand origin had a significant effect on the C-N-P stoichiometry, and also significantly affected leaf N and P reabsorption efficiencies. Leaf N/P ratios indicated that Mongolian pine was co-limited by N and P in the NF, HB and HQ, and was mainly limited by P in MU. (2) With increasing stand age, C concentrations in the leaf-litter-soil system initially increased and then decreased, the N and P concentrations and reabsorption efficiencies in the leaf-litter-soil system were gradually increased. Overall, stand age had a significant effect on N concentrations, C/N and C/P ratios in the leaf-litter-soil system. (3) The C and N elements between the leaf-litter-soil system had a strong coupling relationship, and the P element between litter-soil had a strong coupling relationship. In addition, plantations exhibited greater N/P homeostasis than natural forests, and N/P exhibited greater homeostasis than N and P alone, which may be a nutrient utilization strategy for forests to alleviate N or P limitation. (4) Environmental factors have a significant influence on C-N-P stoichiometry in the leaf-litter-soil system, the most important soil properties and meteorological factors being soil water content and precipitation, respectively. These results will be essential to provide guidance for plantation restoration and management in desert regions.

Fungal complexity and stability across afforestation areas in changing desert environments.

The great achievements in combating desertification are attributed to large-scale afforestation, yet we lack verification of how the stability of the fungal community changes in afforestation areas in desert environments. Here, we present the fungal network structure from different niches (root and bulk soil) of plantations of Mongolian pine, a crucial species for afforestation introduced widely in desertification regions. We assessed changes in community complexity and stability of root-associated fungi (RAF) and soil fungi (SF) among different introduction sites: the Hulunbuir Desert (HB), the Horqin Desert (HQ) and the Mu Us Desert (MU). To illuminate the complexity and stability of the fungal network, the differences in topological properties, fungal function, and vegetation and environmental factors between introduction sites were fully considered. We showed that (1) the SF networks had more nodes and edges than the RAF networks. There was a lower ratio of negative:positive cohesion of RAF networks in HB and MU. For SF but not for RAF, across the three introduction sites, a higher modularity and ratio of negative:positive cohesion indicated higher stability. (2) Ectomycorrhizal (EcM) fungi were the dominant functional group in the RAF network (especially in HQ), and were only significantly correlated with vegetation factor. There was a higher relative abundance and number of OTUs of saprophytic fungi in the SF network and they showed positive correlations with soil nutrients. (3) RAF and SF network complexity and stability showed different responses to environmental and vegetation variables. The key determinant of the complexity and stability of the SF networks in Mongolian pine plantations was soil nutrients, followed by climate conditions. The composition and structure of the RAF community was closely related to host plants. Therefore, clarifying the complexity and stability of fungal communities in afforestation areas in changing desert environments is helpful for understanding the interactions between the environment, plants and fungi.

Temporal approach to identifying ectomycorrhizal community associated with Mongolian pine in a desert environment, northern China.

To date, the ectomycorrhizal (EM) fungi community has been widely investigated with aging plantations affected by the pedologic factors. However, knowledge on the effects of phenology induced by climatic factors across the age range remains poorly understood on an intra-annual scale. Here, we sampled the fine roots of Mongolian pine (Pinus sylvestris var. mongolica) plantations at different stages of the growing season (from April to September) across three stand ages (27, 34, and 44 yr) in the Mu Us Desert, Northwest China. We aim to disentangle the community composition and structure of EM fungi, as well as the impact of climate on EM fungi. We observed that the 173 distinct EM fungal operational taxonomic units (OTUs) were identified. Geopora, Inocybe, Tomentella, and Tuber were the most frequent, and their dominance was maintained as stand aging. The richness and community composition were not significantly different with stand aging (P > 0.05). Host phenology and stand age are two important factors that have shaped the EM fungal community. The growing stage affected the beta diversity of the EM fungal community more than stand age, and this variation of the EM fungal community was closely related to seasonal climate, particularly precipitation. This improved information will provide a theoretical basis for the reforestation and rehabilitation of the Mongolian pine plantations using mycorrhizal techniques. IMPORTANCE Ectomycorrhizal (EM) fungi are particularly important for host plants in a desert ecosystem. With a high degree of plasticity, EM fungi are largely influenced by host plant and environmental variables and fundamentally contribute to the ability of individuals to adapt to environmental changes. Therefore, the EM fungi are important for Mongolian pine (Pinus sylvestris var. mongolica) plantation in a desert ecosystem. Although previous studies have concluded that multiple endogenous and exogenous processes ultimately lead to species-specific temporal patterns in EM fungal populations. We still neglect the effect of host phenology on EM fungal activity. The significance of our study is the interplay between climate-driven EM fungi and plant phenology.

[Temporal and Spatial Variations in Root-associated Fungi Associated with Pinus sylvestris var. mongolica in the Semi-arid and Dry Sub-humid Desertified Regions of Northern China].

To illuminate the ecological functions of root-associated fungi (RAF) and their interactions with host plants, we revealed the root-associated fungal diversity and community compositions of Pinus sylvestris var. mongolica involving natural forests and plantations (half-mature, nearly mature, and mature forests) in the Hulunbuir Desert, Horqin Desert, and Mu Us Desert and investigated the environmental driving factors (climatic condition and soil property). The results indicated that: 1 the diversity of RAF in the natural forests was significantly lower than that in plantations (P<0.05), and the values were highest in the Mu Us Desert. There was a distinct geographical distribution in the RAF community, but the influence of stand age was not significant (P>0.05). 2 The relative abundance of ectomycorrhizal fungi (50.49%) in natural forests was higher than that in plantations, such as Acephala, Mycena, and Suillus. The indicator genera were diverse involving the natural forests (Acephala) and plantations in the Hulunbuir Desert (Sarcodon), Horqin Desert (Russula and Calostoma), and Mu Us Desert (Geopora, Mallocybe, and Tomentella). 3 The indicator genera were mainly affected by available nitrogen content, available phosphorus content, and stand age, and few indicator genera were related to soil water content, pH, and total nitrogen content. A total of 43.25% of the variation in the RAF community was accounted for by both geographic location and environmental factors. Overall, geographic location and environmental factors shaped the spatial variation in the RAF structure and function of P. sylvestris natural forests and plantations in the semi-arid and dry sub-humid desertified regions; there were no significant temporal variations in RAF across stand ages, but the nonuniformity in fungal distribution with stand ageing cannot be ignored. The large population of symbiotic fungi in natural forests was conducive to the healthy growth of hosts; the ratio of symbiotic, saprophytic, and pathotrophic fungi varied in different plantations, and the increase in the proportion of saprophytic and pathotrophic fungi may have negative effects on the growth and health of plantations. This improved information will provide a theoretical basis for the management of P. sylvestris plantations.

Synthesis and antitumor activities of five Cu(II) complexes of bis(5-halosalicylidene)-1,3-propanediamine derivatives.

The development of metal complexes of Schiff base has attracted much attention due to their DNA binding properties and extensive biological activities. We reported here five copper(II) complexes [Cu(L1)] (1), [Cu(L2)] (2), [Cu(L3)] (3), [Cu2(L4)(OAc)] (4), and [Cu2(L5)(HCOO)] (5) bearing the bis-Schiff base ligands of bis(5-chlorosalicylidene)-1,3-propanediamine (H2L1), bis(5-chlorosalicylidene)-2-methyl-1,3-propanediamine (H2L2), bis(5-bromosalicylidene)-2-methyl-1,3-propanediamine (H2L3), bis(5-chlorosalicylidene)-2-hydroxyl-1,3-propanediamine (H3L4), and bis(5-bromosalicylidene)-2-hydroxyl-1,3-propanediamine (H3L5), respectively. The single crystal X-ray diffraction analysis results revealed that complexes 1-3 present mononuclear structures and complexes 4 and 5 show dinuclear structures. It was also shown that all of these complexes are stable under physiological conditions. The in vitro antitumor activities of the five complexes were evaluated. Anticancer selectivity was also found for complex 2 on different cell lines with the lowest IC50 value on Hela cells. Further mechanistic studies showed that the three mononuclear Cu(II) complexes can induce apoptosis through the mitochondrial pathway by decreasing mitochondrial membrane potential and increasing the reactive oxygen species (ROS) and Ca2+ levels. They can activate caspase-3 and caspase-9, and can also regulate the expression of pro-apoptotic protein and anti-apoptotic protein in cells. All of these results showed that complex 2 is a potential anticancer drug.

Anticancer activity of four trinuclear cobalt complexes bearing bis(salicylidene)-1,3-propanediamine derivatives.

Schiff base and its complexes are being paid more and more interests for their great prospects in biological applications. We reported here four cobalt(II) complexes [Co3(L1)2(HCOO)2] (1), [Co3(L2)2(HCOO)2(CH3OH)2]·2CH3OH (2), [Co3(HL3)2(OAc)2(DMF)2] (3) and [Co3(HL4)2(HCOO)2(DMF)2]·2H2O (4) bearing the bis-Schiff base ligand of bis(5-bromosalicylidene)-1,3-propanediamine (H2L1), bis(5-bromosalicylidene)-2-methyl-1,3-propanediamine (H2L2), bis(5-chlorosalicylidene)-2-hydroxyl-1,3-propanediamine (H3L3) and bis(5-bromosalicylidene)-2-hydroxyl-1,3-propanediamine (H3L4), respectively. The anti-tumor activities of the four titled complexes were screened on a series of tumor cell lines. After an overall consideration of their cytotoxicity on cancer cells and normal cells in comparison to those for cisplatin, complex 3 shows the best anticancer effect among the four titled complexes. It revealed the influence of anti-cancer effects of the substitution groups of H, Me and OH, as well as Cl and Br. Anticancer selectivity was also found for complex 3 on different cancer cell lines with the lowest IC50 value on T-24 cells. Complex 3 induces cell apoptosis through mitochondrial pathway as demonstrated by increasing the level of reactive oxygen species, decreasing mitochondrial membrane potential, activating caspase 3/9 and arresting cell cycle in G1 phase.

Why is the labor epidural rate low and cesarean delivery rate high? A survey of Chinese perinatal care providers.

OBJECTIVE: China has a high cesarean delivery (CD) and low labor epidural analgesia (LEA) rate. This online survey was conducted to explore the reasons behind this phenomenon and potential solutions. METHODS: A voluntary, anonymous survey was distributed via both WeChat and professional websites for 4 months amongst groups of Chinese perinatal professionals. Data was collected and analyzed using a Chi-square test and presented as percentages of respondents. RESULTS: 1412 respondents were recorded (43% anesthesiologists, 35% obstetricians, 15.5% midwives or labor and delivery nurses, and 6.5% others), and 1320 respondents were care providers. It was found that 82.7% (1092/1320) of the provider respondents used CD per patient request in fear of lawsuits or yinao/yibao and 63.4% (837/1320) used CD for respecting superstitious culture. The number one reason (noted by 60.2% (795/1320) of all the three specialties) for low LEA use was lack of anesthesia manpower without statistical difference among specialties. The most recommended solution was increasing the anesthesia workforce, proposed by 79.8% (1053/1320) of the three specialties. However, the top solution provided by the two non-anesthesia specialties is different from the one proposed by anesthesiologists. The later (83%, 504/606) suggested increasing the incentive to provide the service is more effective. The answers to questions related to medical knowledge about CD and LEA, and unwillingness of anesthesiologists, parturients and their family members to LEA were similar for the most part, while the opinions regarding low LEA use related to poor experiences and unwillingness of obstetricians and hospital administrators were significantly divided among the three specialties. In the providers' point of view, the unwillingness to LEA from parturient's family members was the most salient (26.1%, 345/1320), which is more than all care providers, hospital administrators, and parturients themselves (16.8%, 222/1320). CONCLUSION: The reasons for high CD rate and low LEA use are multifactorial. The sociological issues (fear of yinao/yibao and superstitious culture) were the top two contributing factors for the high CD rate in China, while lack of anesthesia manpower was the top response for the low LEA use, which contributes to its being the most recommended solution overall from the three specialties. An incentive approach to providers is a short-term solution while training more perinatal care providers (especially among anesthesiologists and midwives), improving billing systems, and reforming legal systems are 3 systemic approaches to tackling this problem in the long-term.

Community structure and functional group of root-associated Fungi of Pinus sylvestris var. mongolica across stand ages in the Mu Us Desert.

Root-associated fungi (RAF) are an important factor affecting the host's growth, and their contribution to Pinus sylvestris var. mongolica plantation decline is substantial. Therefore, we selected three age groups of P. sylvestris plantations (26, 33, and 43 years), in the Mu Us Desert, to characterize the community structure and functional groups of RAF, identified by Illumina high-throughput sequencing and FUNGuild platform, respectively. The effects of soil properties and enzyme activities on fungal diversity and functional groups were also examined. The results indicated that (a) 805 operational taxonomic units of RAF associated with P. sylvestris belonged to six phyla and 163 genera. Diversity and richness were not significantly different in the three age groups, but community composition showed significant differences. Ascomycota and Basidiomycota dominated the fungal community, while Rhizopogon dominated in each plot. (b) The proportion of pathotrophs decreased with increasing age, while that of symbiotrophs increased sharply, which were mainly represented by ectomycorrhizal fungi. (c) Stand age and soil enzyme activity had a greater influence on fungal community composition than did soil properties, whereas environmental variables were not significantly correlated with fungal diversity and richness. Dynamics of fungal community composition and functional groups with the aging plantations reflected the growth state of P. sylvestris and were related to plantation degradation.

Was Mafeisan an Anesthetic in Ancient China?

According to the Chinese historical books, Records of the Three Kingdoms () and Book of the Later Han (), Hua Tuo (, 140 - 208), a Traditional Chinese medicine (TCM) physician invented Mafeisan, an oral herbal general anesthetic, more than 1800 years ago during Eastern Han Dynasty. However, no written record of ingredients of the original Mafeisan has been found anywhere so far although there have been several similar anesthetic prescriptions published in TCM books later. There has been controversy over the existence of Mafeisan and even Hua Tuo in Chinese literature. We did extensive literature search and analysis, and believe that there indeed was Mafeisan in Hua Tuo's time.

American-trained Chinese anesthesiologists: how are they doing?

More than 60 years have passed since 3 pioneer Chinese anesthesiologists were trained by American physicians. After returning to China, they applied their new knowledge and skills to develop a new anesthesia specialty in their own country. Over the past 2 decades, close to 600 Chinese medical graduates have been trained in the United States and have become part of the American anesthesia workforce. Unlike their elder generation, they did not go back to China after their training. People are always wondering how this new generation of American-trained Chinese anesthesiologists is doing in a different culture and different health care and political systems. This review indicates that these newly American-trained Chinese anesthesiologists not only provide high-quality patient care but also conduct outstanding anesthesia teaching and research. In addition, as their pioneer anesthesiologists did in China, they use professional organizations and publications as 2 major means to advance professional development and promote academic exchanges between Chinese and American anesthesiologists, through which American anesthesiology continues to have influence on modern Chinese anesthesiology.

No Pain Labor & Delivery: A Global Health Initiative's Impact on Clinical Outcomes in China.

The availability of labor analgesia is highly variable in the People's Republic of China. There are widespread misconceptions, by both parturients and health care providers, that labor epidural analgesia is harmful to mother and baby. Meanwhile, China has one of the highest cesarean delivery rates in the world, exceeding 50%. The goal of the nongovernmental No Pain Labor & Delivery (NPLD) is to facilitate sustainable increases in vaginal delivery rates by increasing access to safe neuraxial labor analgesia, thereby decreasing the cesarean delivery rate. NPLD was launched in 2008 with the stated goal of improving labor outcome in China by increasing the absolute labor epidural analgesia rate by 10%. NPLD established 10 training centers over a 10-year period. We hypothesized that increased availability of labor analgesia would result in reduced requests for cesarean delivery and better labor outcomes for mother and baby. Multidisciplinary teams of Western clinicians and support staff traveled to China for 8 to 10 days once a year. The approach involved establishing 24/7 obstetric anesthesia coverage in Chinese hospitals through education and modeling multidisciplinary approaches, including problem-based learning discussions, bedside teaching, daily debriefings, simulation training drills, and weekend conferences. As of November 2015, NPLD has engaged with 31 hospitals. At 24 of these sites, 24/7 obstetric anesthesia coverage has been established and labor epidural analgesia rates have exceeded 50%. Lower rates of cesarean delivery, episiotomy, postpartum blood transfusion, and better neonatal outcomes were documented in 3 impact studies comprising approximately 55,000 deliveries. Changes in practice guidelines, medical policy, and billing codes have been implemented in conjunction with the modernization of perinatal practice that has occurred concurrently in China since the first NPLD trip in 2008.