Methane emissions by alpine plant communities in the Qinghai-Tibet Plateau

For the first time to our knowledge, we report here methane emissions by plant communities in alpine ecosystems in the Qinghai-Tibet Plateau. This has been achieved through long-term field observations from June 2003 to July 2006 using a closed chamber technique. Strong methane emission at the rate of 26.2+/-1.2 and 7.8+/-1.1microg CH4 m-2h-1 was observed for a grass community in a Kobresia humilis meadow and a Potentilla fruticosa meadow, respectively. A shrub community in the Potentilla meadow consumed atmospheric methane at the rate of 5.8+/-1.3microg CH4 m-2h-1 on a regional basis; plants from alpine meadows contribute at least 0.13Tg CH4 yr-1 in the Tibetan Plateau. This finding has important implications with regard to the regional methane budget and species-level difference should be considered when assessing methane emissions by plants.     

Up-regulation of mitochondrial activity and acquirement of brown adipose tissue-like property in the white adipose tissue of fsp27 deficient mice

Fsp27, a member of the Cide family proteins, was shown to localize to lipid droplet and promote lipid storage in adipocytes. We aimed to understand the biological role of Fsp27 in regulating adipose tissue differentiation, insulin sensitivity and energy balance. Fsp27(-/-) mice and Fsp27/lep double deficient mice were generated and we examined the adiposity, whole body metabolism, BAT and WAT morphology, insulin sensitivity, mitochondrial activity, and gene expression changes in these mouse strains. Furthermore, we isolated mouse embryonic fibroblasts (MEFs) from wildtype and Fsp27(-/-) mice, followed by their differentiation into adipocytes in vitro. We found that Fsp27 is expressed in both brown adipose tissue (BAT) and white adipose tissue (WAT) and its levels were significantly elevated in the WAT and liver of leptin-deficient ob/ob mice. Fsp27(-/-) mice had increased energy expenditure, lower levels of plasma triglycerides and free fatty acids. Furthermore, Fsp27(-/-)and Fsp27/lep double-deficient mice are resistant to diet-induced obesity and display increased insulin sensitivity. Moreover, white adipocytes in Fsp27(-/-) mice have reduced triglycerides accumulation and smaller lipid droplets, while levels of mitochondrial proteins, mitochondrial size and activity are dramatically increased. We further demonstrated that BAT-specific genes and key metabolic controlling factors such as FoxC2, PPAR and PGC1alpha were all markedly upregulated. In contrast, factors inhibiting BAT differentiation such as Rb, p107 and RIP140 were down-regulated in the WAT of Fsp27(-/-) mice. Remarkably, Fsp27(-/-) MEFs differentiated in vitro show many brown adipocyte characteristics in the presence of the thyroid hormone triiodothyronine (T3). Our data thus suggest that Fsp27 acts as a novel regulator in vivo to control WAT identity, mitochondrial activity and insulin sensitivity.     

Biomass Yield and Nutrient Uptake of Energy Sorghum in Response to Nitrogen Fertilizer Rate on Marginal Land in a Semi-Arid Region

Energy sorghum tolerates adverse climatic and edaphic conditions and has great potential as biofuel feedstock in marginal land. This study investigates the potential energy sorghum biomass production and uptake of nitrogen (N), phosphorus (P), and potassium (K) on a sandy loam marginal land in a semi-arid region, in order to define optimum N fertilizer rate to produce the highest biomass yield with minimal nutrient elimination. Five N rate treatments (0, 60, 120, 180, and 240 kg ha^?1) and two sorghum varieties (sweet type Guotian-8 (GT-8) and biomass type Guoneng-11 (GN-11)) were used. Yield increment was observed as N level increased, but the standout treatment appeared to be N rate of 60 kg ha^?1 which significantly increased biomass yield vs. controls by 68.8% in 2014 and 64.1% in 2015. Biomass yield exhibited non-significant differences between N rate treatments from 60 to 240 kg ha^?1, although the highest biomass yield (9.2–11.9 t ha^?1) was observed in the 120 kg N ha^?1 treatment. Nutrient analysis showed that N, P, and K accumulation in aboveground plants increased with N rate increase, ranging between 32.2 and 119.1, 7.9 and 19.2, and 22.1 and 94.0 kg ha^?1, respectively, for the highest N rate of 240 kg ha^?1. Substantial amounts of N were extracted from the soil in control and 60 kg N ha^?1 treatments, despite the low fertility and organic matter content of the soil. Moreover, nitrogen (N) use efficiency (NUE) was maximized at lower N rates. A decline in physiological N use efficiency (PNUE) resulted in decreased agronomic N use efficiency (ANUE) at higher N rates. Hence, it is concluded that N fertilizer rate between 60 and 120 kg ha^?1 would be the optimal N requirement to facilitate sustainable production of energy sorghum on a sandy wasteland.     

Relationships between the molecular structure and moisture-absorption and moisture-retention abilities of carboxymethyl chitosan. II. Effect of degree of deacetylation and carboxymethylation

Carboxymethyl chitosans (CM-chitosan) of various degrees of deacetylation (DD 28-95%) and substitution (DS 0.15-1.21) were successfully prepared from N-acetylchitosans in NaOH of varying concentrations. Infrared spectroscopy (IR), elemental analysis, potentiometric titration, 13C NMR, X-ray diffraction and gel-permeation chromatographic (GPC) techniques were used to characterize their molecular structures. The moisture-absorption (R(a)) and -retention (R(h)) abilities of CM-chitosan are closely related to the DD and DS values. Under conditions of high relative humidity, the maximum R(a) and R(h) were obtained at DD values of about 50%, and when the DD value deviated from 50%, R(a) and R(h) decreased. Under dry conditions, when the DD value was 50%, the R(h) was the lowest. With the DS value increasing, R(a) and R(h) increased. However, further increase of the DS value above 1.0 reduced the increasing tendency of R(a) and R(h), and even some decreases in R(a) and R(h) were observed. Intermolecular hydrogen bonds play a very important role in moisture-absorption and retention ability of CM-chitosan.     

褪黑素对盐胁迫下普通菜豆芽期核酸修复的调控机制

普通菜豆(Phaseolus vulgaris)是重要的食用豆作物,然而其极易受盐胁迫危害,导致产量下降。褪黑素能提高植物耐盐能力。为探明外源褪黑素调控普通菜豆耐盐能力的机制,以普通菜豆品种奶花芸豆(GZ-YD014)为实验材料,设置水(W,对照)、盐胁迫(S)和盐胁迫+100μmol·L^–1褪黑素(M+S) 3个处理。结果发现,盐胁迫抑制了普通菜豆胚根的生长,使其长度、表面积、体积以及直径显著降低,外源褪黑素可缓解盐胁迫对普通菜豆胚根生长的抑制。外施褪黑素显著降低盐胁迫下活性氧积累和丙二醛(MDA)含量,提高保护酶(过氧化物酶、超氧化物歧化酶、过氧化氢酶以及抗坏血酸过氧化物酶)活性,增加渗透调节物质(可溶性糖和可溶性蛋白)以及生长素(IAA)、赤霉素(GA)和玉米素(ZT)的含量,降低脱落酸(ABA)含量。通过转录组分析挖掘出217个差异表达基因(DEGs),DEGs在GO富集中显著(P-value<0.05)富集到核酸相关条目上,在KEGG富集中显著(P-value<0.05)富集到核酸损伤修复(包括碱基切除修复、错配修复以及核苷酸切除修复)通路。...     

Colonization of endophyte Acremonium sp. D212 in Panax notoginseng and rice mediated by auxin and jasmonic acid

Endophytic fungi can be beneficial to plant growth. However, the molecular mechanisms underlying colonization of Acremonium spp. remain unclear.In this study, a novel endophytic Acremonium strain was isolated from the buds of Panax notoginseng and named Acremonium sp. D212. The Acremonium sp. D212 could colonize the roots of P. notoginseng,enhance the resistance of P. notoginseng to root rot disease, and promote root growth and saponin biosynthesis in P. notoginseng. Acremonium sp. D212 could secrete indole-3-acetic acid(IAA) and jasmonic acid(JA), and inoculation with the fungus increased the endogenous levels of IAA and JA in P. notoginseng. Colonization of the Acremonium sp. D212 in the roots of the rice line Nipponbare was dependent on the concentration of methyl jasmonate(Me JA)(2–15 μmol/L) and 1-naphthalenacetic acid(NAA)(10–20 μmol/L). Moreover, the roots of the JA signaling-defective coi1-18 mutant were colonized by Acremonium sp. D212 to a lesser degree than those of the wild-type Nipponbare and mi R393 boverexpressing lines, and the colonization was rescued by Me JA but not by NAA. It suggests that the cross-talk between JA signaling and the auxin biosynthetic pathway plays a crucial role in the colonization of Acremonium sp. D212 in host plants.     

Effects of patient-controlled analgesia with hydromorphone or sufentanil on postoperative pulmonary complications in patients undergoing thoracic surgery: a quasi-experimental study

Objective

To compare the analgesic effects of patient-controlled intravenous analgesia (PCA) with hydromorphone and sufentanil after thoracic surgery on postoperative pulmonary complications (PPCs).

Methods

A total of 142 patients who were scheduled for thoracic surgery were randomly allocated to receive PCA with hydromorphone (group A: experimental group): hydromorphone 0.2?mg/kg?+?dezocine 0.5?mg/kg?+?ramosetron 0.6?mg diluted with normal saline to 200?mL; or with sufentanil (group B: control group): sufentanil 3.0μg/kg?+?dezocine 0.5?mg/kg?+?ramosetron 0.6?mg diluted with normal saline to 200?mL. The parameters of intravenous analgesia pump were set as background dose 4?ml/h, PCA dose 1?mL, locking time 15?min. Pain NRS (numerical rating scale), Ramsay sedation score, nausea or vomiting score were evaluated at 0?h, 6?h, 12?h, 24?h, 48?h after operation. The cases of PPCs (atelectasis, pulmonary infection, respiratory failure), CRP (C-reaction protein) and inflammatory cells (white cell count and percentage of neutrophils) and blood gas analysis at 12?h after operation, length of ICU and postoperative stay were recorded for each patient.

Results

Data of 136 patients were analyzed. Compared with group B (4[IQR:2,2]), the pain NRS in group A (2[IQR:4,4]) was significantly lower at 6?h after operation (P?=?0.000). The CRP in group A (69.79?±?32.13?mg/L) were lower than group B (76.76?±?43.42?mg/L) after operation, but the difference was not significant (P?=?0.427). No difference of nausea or vomiting was found between group A (7.3%) and group B (5.8%) postoperatively (P?=?0.999). The PPCs were happened in 11 patients in group A (16.2%) and 22 patients in group B (32.4%) and the difference between two groups was significant (P?=?0.027). Seven patients in group A (10.3%) and eighteen patients in group B (26.5%) had clinical evidence of pneumonia and the difference between two groups was significant (P?=?0.014). The length of ICU and postoperative stay in group A were 2.73?h and 1.82?days less than group B respectively but the differences were not significant (P?=?0.234, P?=?0.186 respectively).

Conclusion

Compared with sufentanil, hydromorphone may provide better postoperative analgesic effect with less pulmonary complications for patients undergoing thoracic surgery, and it may accelerate patients’ rehabilitation.

Trial registration

Randomized Controlled Trials ChiCTR1800014282c. Registered 3 January 2018.