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In this study, the variational method concerning displacement components is applied to solve the large deformation problem of a thin cylindrical shell with its four sides fully fixed and under uniformly distributed loads, in which the material that constitutes the shell has a bimodular effect, in comparison to traditional materials, that is, the material will present different moduli of elasticity when it is in tension and compression. For the purpose of the use of the displacement variational method, the physical equations on the bimodular material model and the geometrical equation under large deformation are derived first. Thereafter, the total strain potential energy is expressed in terms of the displacement component, thus bringing the possibilities for the classical Ritz method. Finally, the relationship between load and central deflection is obtained, which is validated with the numerical simulation, and the jumping phenomenon of thin cylindrical shell with a bimodular effect is analyzed. The results indicate that the bimodular effect will change the stiffness of the shell, thus resulting in the corresponding change in the deformation magnitude. When the shell is relatively thin, the bimodular effect will influence the occurrence of the jumping phenomenon of the cylindrical shell.

Aims Understanding the patterns and drivers of carbon isotope discrimination (13Δ) in C3 and C4 functional groups is critical for predicting C3/C4 vegetation ratio from the isotopic composition of soil organic matter. In this study, we aimed to evaluate how intraspecific variation will modify functional group-level 13Δ values and the associated prediction of C3/C4 vegetation ratio. Methods We investigated 13Δ of 726 individual plants (96 species; C3 and C4 functional groups) and topsoil organic matter in 26 grassland communities along an aridity gradient in northern China. The fraction of C4 contribution was calculated with mixing models that considered: (i) both intra- and interspecific effects on the 13Δ values of C3 and C4 functional groups; (ii) only interspecific effects; or (iii) none of these effects. Important Findings We found divergent responses of plant 13Δ at the intraspecific level to the changes of aridity across the gradient. The 13Δ of both C3 and C4 functional groups was negatively correlated with an aridity index, with higher sensitivity for C3 than for C4 functional groups. Intraspecific 13Δ variation played a key role in driving the total 13Δ variations of C3 plants. Overlooking such intraspecific effect in mixing models led to a greatly increased fraction of C4 contribution to soil organic carbon. A correction for the effects of intraspecific variation is therefore essential for correctly inferring C3/C4 vegetation ratio in the past. Our findings provide basic information for the reconstruction of past vegetation change from bulk materials in arid and semiarid biomes.

Stress-induced neuroepigenetic programming gains growing more and more interest in the studies of the etiology of posttraumatic stress disorder (PTSD). However, seldom attention is focused on DNA demethylation in fear memory generalization, which is the core characteristic of PTSD. Here, we show that ten-eleven translocation protein 3 (TET3), the most abundant DNA demethylation enzyme of the TET family in neurons, senses environmental stress and bridges neuroplasticity with behavioral adaptation during fear generalization. Foot shock strength dependently induces fear generalization and TET3 expression in nucleus accumbens (NAc) in mice. Inhibition of DNA demethylation by infusing demethyltransferase inhibitors or AAV-Tet3-shRNA virus in NAc enhances the fear generalization and anxiety-like behavior. Furthermore, TET3 knockdown impairs the dendritic spine density, PSD length, and thickness of neurons, decreases DNA hydroxymethylation (5hmC), reduces the expression of synaptic plasticity-related genes including Homer1, Cdkn1a, Cdh8, Vamp8, Reln, Bdnf, while surprisingly increases immune-related genes Stat1, B2m, H2-Q7, H2-M2, C3, Cd68 shown by RNA-seq. Notably, knockdown of TET3 in NAc activates microglia and CD39-P2Y12R signaling pathway, and inhibition of CD39 reverses the effects of TET3 knockdown on the fear memory generalization and anxiety. Overexpression of TET3 by Crispr-dSaCas9 virus delivery to activate endogenous Tet3 in NAc increases dendritic spine density of neurons in NAc and reverses fear memory generalization and anxiety-like behavior in mice. These results suggest that TET3 modulates fear generalization and anxiety via regulating synaptic plasticity and CD39 signaling pathway.

Fear memories are critical for survival. Nevertheless, over-generalization of these memories, depicted by a failure to distinguish threats from safe stimuli, is typical in stress-related disorders. Previous studies have supported a protective role of ketamine against stress-induced depressive behavior. However, the effect of ketamine on fear generalization remains unclear. In this study, we investigated the effects of ketamine on fear generalization in a fear-generalized mouse model. The mice were given a single sub-anesthetic dose of ketamine (30 mg/kg, i.p.) 1 h before, 1 week before, immediately after, or 22 h after fear conditioning. The behavioral measure of fear (indicated by freezing level) and synaptic protein expression in the basolateral amygdala (BLA) and inferior-limbic pre-frontal cortex (IL-PFC) of mice were examined. We found that only ketamine administered 22 h after fear conditioning significantly decreased the fear generalization, and the effect was dose-dependent and lasted for at least 2 weeks. The fear-generalized mice showed a lower level of brain-derived neurotrophic factor (BDNF) and a higher level of GluN2B protein in the BLA and IL-PFC, and this was reversed by a single administration of ketamine. Moreover, the GluN2B antagonist ifenprodil decreased the fear generalization when infused into the IL-PFC, but had no effect when infused into the BLA. Infusion of ANA-12 (an antagonist of the BDNF receptor TrkB) into the BLA or IL-PFC blocked the effect of ketamine on fear generalization. These findings support the conclusion that a single dose of ketamine administered 22 h after fear conditioning alleviates the fear memory generalization in mice and the GluN2B-related BDNF signaling pathway plays an important role in the alleviation of fear generalization. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s12264-019-00422-4) contains supplementary material, which is available to authorized users.

Aim To identify mutations with whole exome sequencing (WES) in a Chinese X-linked retinitis pigmentosa (XLRP) family. Methods Patients received the comprehensive ophthalmic evaluation. Genomic DNA was extracted from peripheral blood and subjected to SureSelect Human All Exon 6+ UTR exon capture kit. The exons were sequenced as 100 base paired reads on Illumina HiSeq2500 system. Only mutations that resulted in a change in amino acid sequence were selected. A pattern of inheritance of the RP family was aligned to identified causal mutation. Results We analysed the data of WES information from XLRP family. The analysis revealed a hemizygous large genomic deletion of RPGR c.29_113del was responsible for this XLRP. The gross deletion lead to a frame-shift mutation and generate stop codon at 7 animo acid behind Asp (D10Afs*7), which would serious truncate RPGR protein. The novel frame-shift mutation was found to segregate with retinitis pigmentosa (RP) phenotype in this family. Bilateral myopia was present on the male patients, but carrier female showed unilateral myopia without RP. Conclusion Our study identifies a novel frame-shift mutation of RPGR in a Chinese family, which would expand the spectrum of RPGR mutations. The geno-phenotypic analysis reveals a correlation between RP and myopia. Although exact mechanism of RP related myopia is still unknown, but the novel frame-shift mutation will give our hit on studying the molecular pathogenesis of RP and myopia.

Hepatic injury is one of the most challenging diseases in clinical medicine. Hepatic injury is accompanied by hepatocyte apoptosis and leads to hepatic fibrosis and cirrhosis, which may cause liver cancer and increased mortality. Therefore, it is essential to investigate the regulation mechanism and therapeutic strategies for hepatic injury. In the study, the effects of Thymosin β4 (Tβ4) on Long intergenic noncoding RNA-p21 (lincRNA-p21)-mediated liver injury were investigated. Results showed that lincRNA-p21 overexpression promoted hepatocytes apoptosis, which was blocked by Tβ4. Besides, Tβ4 reversed the levels of cleaved caspase-3 and caspase-9 induced by lincRNA-p21. LincRNA-p21 overexpression also caused the pathological injury and fibrosis in hepatic tissues and increased the levels of fibrosis-related proteins (Collagen I, α-SMA and TIMP-1), and induced hydroxyproline and ALT production. However, Tβ4 reversed the effects of overexpression of lincRNA-p21 on hepatic injury and fibrosis. In vitro experiments, after lincRNA-p21 was overexpressed in hepatic stellate cells (HSCs), the proliferation ability and the levels of HSCs markers α-SMA and Desmin were increased. However, Tβ4 reversed the effects of lincRNA-p21 on HSCs. Furthermore, the PI3K-AKT-NF-κB pathway was activated by lincRNA-p21, which was then reversed by the Tβ4 administration. After the mice treated by insulin-like growth factor-1 (IGF-1) (the activator of PI3K-AKT), the inhibitory effect of Tβ4 on activated the PI3K-AKT-NF-κB pathway was abrogated. Besides, IGF-1 abolished the protective effects of Tβ4 on hepatic apoptosis and fibrosis induced by lincRNA-p21. Therefore, Tβ4 reversed. lincRNA-p21-mediated liver injury through inhibiting PI3K-AKT-NF-κB pathway. Tβ4 may be a promising drug for fibrosis therapy.

Background Early-life stress increases the risk for posttraumatic stress disorder. However, the epigenetic mechanism of early-life stress-induced susceptibility to posttraumatic stress disorder in adulthood remains unclear. Methods Rat pups were exposed to maternal deprivation during postnatal days 1 to 14 for 3 hours daily and treated with the DNA methyltransferase inhibitor zebularine, L-methionine, or vehicle 7 days before contextual fear conditioning, which was used as a second stress and to mimic the reexperiencing symptom of posttraumatic stress disorder in adulthood. Long-term potentiation, dendritic spine density, DNA methyltransferase mRNA, Reelin gene methylation, and Reelin protein expression in the hippocampal CA1 were measured. Results Maternal deprivation enhanced contextual fear memory in adulthood. Meanwhile, maternal deprivation decreased DNA methyltransferase mRNA and Reelin gene methylation in the hippocampal CA1 on postnatal days 22 and 90. Reelin protein expression was increased in the hippocampal CA1 following contextual fear conditioning in adulthood. Furthermore, compared with rats that experienced maternal deprivation alone, rats also exposed to contextual fear conditioning showed an enhanced induction of hippocampal long-term potentiation and increased dendritic spine density in the hippocampal CA1 following contextual fear conditioning in adulthood. Zebularine pretreatment led to an enhancement of contextual fear memory, hypomethylation of the Reelin gene, and increased Reelin protein expression in adult rats, while L-methionine had the opposite effects. Conclusions Maternal deprivation can epigenetically program second-hit stress-induced Reelin expression and enhance the susceptibility to contextual fear memory in adulthood. These findings provide a new framework for understanding the cumulative stress hypothesis.

The nitrogen isotope composition (δ15N) of plants in arid and semiarid grasslands is affected by environmental factors, especially water availability. Nevertheless, it is unclear whether the response of δ15N to water availability differs between C3 and C4 photosynthetic pathways. We investigated plant δ15N of coexisting C3 and C4 species as a function of aridity along a 3200 km aridity gradient across the arid and semi-arid grasslands of northern China. Aridity was positively correlated with plant δ15N values in both C3 and C4 plants and also in the entire plant community, whereas soil bulk δ15N values increased first and then decreased along the aridity gradient. The N uptake by C4 plants appeared to be more affected by competition pressure of neighboring plants and soil microbes than for C3 plants along the transect. The decoupled relationship between plant and soil δ15N values indicated that variations in vegetation and soil δ15N values were driven by differential biogeochemical processes, while different soil N sources were used for plant growth along the climatic gradient. The advantage of C3 plants in the use of N may counteract the competitive advantage that C4 plants have over C3 plants due to their higher water use efficiency under drier conditions. These findings can help understand why C4 plants do not completely replace C3 plants in drier environments despite their higher water use efficiency.

Semicarbazide (SEM) is a by-product of azodicarbonamide used to improve the properties of the plastic seals of the glass jar lids of the canned food such as baby food. This work aimed to evaluate the effect of semicarbazide (SEM) on the morphology of testicular seminiferous tubules of juvenile albino rat. Twenty juvenile male albino rats aged 4 weeks were divided into two main groups: group I (control), group II (treated with SEM 40 mg/kg oral daily for 4 weeks). Specimens from the testes were processed for different histological examinations, histochemical staining with Periodic Acid Schiff (PAS) and immunohistochemical study using antibodies against Bcl-2 was carried out in addition to morphometrical and statistical analysis. SEM-treated group showed some vacuolated spermatogenic and Sertoli cells, discontinuity of germinal epithelium, some exfoliated spermatogenic cells in the lumen in addition to focal loss of the basement membrane. A statistically significant decrease in both mean epithelial height and area percentage was recorded in group II. A statistically significant decrease of PAS reaction of the basement membrane was observed. A statistically significant decrease in Bcl-2 positive cytoplasmic immunoreaction in cells of seminiferous tubules was detected. Electron microscopic examination revealed swollen mitochondria, dilated rough endoplasmic reticulum, vacuolated cytoplasm and areas of cytoplasmic loss in spermatogenicand Sertoli cells. The nuclei of some primary spermatocytes and spermatids appeared dark and shrunken or fragmented. Thickened basement membrane with collagen deposition was detected. It could be concluded that SEM causes significant structural changes in juvenile seminiferous tubules of rat testis.So, it is recommended to use alternative safe substance in the sealing process of glass jar lids.

Summary Combining nutrient dynamics (plant nutrient uptake and soil fertility) can help uncover mechanisms of shrub-grass interactions and assess the validity of the stress-gradient hypothesis, which predicts that facilitation between plants increases in stressful environments. However, how facilitation via shrub-mediated nutrient increases varies with precipitation is poorly resolved. We first synthesized a global dataset from 66 studies and evaluated how shrubs affected soil organic carbon (C) and nitrogen (N) in grasslands along a precipitation gradient. We then made new measurements in a single grassland type encroached by leguminous shrubs from the same genus (Caragana) to constrain the variations caused by combining different grassland types and shrubs traits in the meta-analysis. Specifically, we investigated how shrubs mediated N dynamics and how shrub-grass interactions varied along a precipitation gradient (147-342 mm) in a temperate steppe of China. At the global scale, leguminous shrub-mediated effects on soil nutrients increased with precipitation, while no relationship was found for non-leguminous shrub. For the field experiment, greater N and lower δ15N in Caragana compared to non-leguminous shrub (reference shrub, Salsola collina) suggested active N-fixation in Caragana. We found that Caragana enhanced N concentration and leaf quality (low C:N ratio) in neighbouring plants more on mesic sites than on xeric sites. Thus, facilitation increased via higher soil N and with decreasing environmental stress, at least along this relatively arid precipitation gradient. Our results highlight the importance of precipitation in determining the nutritional facilitation to neighbouring grasses from encroaching leguminous shrubs. Conceptual frameworks for plant facilitation may therefore need to include shrub characteristics (N-fixers vs. non-fixers) and positive effects of higher precipitation on this type of facilitation to characterize plant interactions along stress gradients. This article is protected by copyright. All rights reserved.

Objective: To study the protective effect of resveratrol on secondary lung injury in intestinal ischemia reperfusion and its effect on P38MAPK pathway. Methods: Adult male SPF SD rats were selected and divided into control group, I/R group, Res-L group, Res-M group and Res-H group, the small intestinal ischemia reperfusion model was made, and Res-L group, Res-M group and Res-H group were given 5.0 mg/kg, 10.0 mg/kg and 15.0 mg/kg resveratrol for intervention. The contents of P38MAPK pathway molecules as well as downstream apoptotic molecules, inflammatory factors and oxidative stress products in the lung were detected. Results: P38MAPK, MAPKK, MAPKKK, Fas, FasL, caspase-8, caspase-9, NF-kB, TNF-α and IL-1β expression as well as ROS and MDA contents in lung tissue of I/R group were significantly higher than those of control group; P38MAPK, MAPKK, MAPKKK, Fas, FasL, caspase-8, caspase-9, NF-kB, TNF-α and IL-1β expression as well as ROS and MDA contents in lung tissue of Res-L group, Res-M group and Res-H group were significantly lower than those of I/R group. Conclusion: Resveratrol can inhibit the function of P38MAPK pathway to reduce apoptosis, inflammation and oxidative stress, and then protect the secondary lung injury induced by intestinal ischemia reperfusion.

We introduce a generalized Rashba coupling approximation to analytically solve confined two-dimensional electron systems with both the Rashba and Dresselhaus spin–orbit couplings in an external magnetic field. A solvable Hamiltonian is obtained by performing a simple change of basis, which has the same form as that with only Rashba coupling. Each Landau state becomes a new displaced-Fock state instead of the original Harmonic oscillator Fock state. Analytical energies are consistent with the numerical ones in a wide range of coupling strength even for a strong Zeeman splitting, exhibiting the validity of the analytical approximation. By using the eigenstates, spin polarization correctly displays a jump at the energy-level crossing point, where the corresponding spin conductance exhibits a pronounced resonant peak. As the component of the Dresselhaus coupling increases, the resonant point shifts to a smaller value of the magnetic field. In contrast to pure Rashba couplings, we find that the Dresselhaus coupling and Zeeman splittings tend to suppress the resonant spin Hall effect. Our method provides an easy-to-implement analytical treatment to two-dimensional electron gas systems with both types of spin–orbit couplings by applying a magnetic field.

Climate factors such as aridity significantly influence soil carbon (C) and nitrogen (N) stocks in terrestrial ecosystems. Further, soil texture plays an important role in driving changes of soil C and N contents at regional scale. However, it remains uncertain whether such changes resulted from the variation of different soil particle–size factions and/or the C and N concentrations in those fractions. We examined the distribution of total C and N in both bulk soil and different soil particle–size fractions, including sand (53–2000 µm), silt (2–53 µm), and clay (

Objective: To analyze the effect of different anesthesia methods on inflammation and oxidative stress in patients with laparoscopic hysterectomy. Methods: A total of 75 cases who received laparoscopic hysterectomy in our hospital from September 2012 to February were included in the research and divided into simple general anesthesia group 40 cases and combined general and epidural anesthesia group 35 cases according to different anesthesia methods. Peripheral venous blood was drawn from patients to detect the differences in inflammationrelated indexes, immune molecule-related indexes, cerebral oxygen metabolism as well as cerebral blood flow and oxidative stress-related indexes, etc in it. Results: Postoperative MBP, MCP-1, HMGB1 and LBP values of observation group were lower than those of control group while Ins value was higher than that of control group (P

Objective: This review focuses on the current knowledge on the implication and significance of beta 2 microglobulin (β2M), a conservative immune molecule in vertebrate. Data Sources: The data used in this review were obtained from PubMed up to October 2015. Terms of β2M, immune response, and infection were used in the search. Study Selections: Articles related to β2M were retrieved and reviewed. Articles focusing on the characteristic and function of β2M were selected. The exclusion criteria of articles were that the studies on β2M-related molecules. Results: β2M is critical for the immune surveillance and modulation in vertebrate animals. The dysregulation of β2M is associated with multiple diseases, including endogenous and infectious diseases. β2M could directly participate in the development of cancer cells, and the level of β2M is deemed as a prognostic marker for several malignancies. It also involves in forming major histocompatibility complex (MHC class I or MHC I) or like heterodimers, covering from antigen presentation to immune homeostasis. Conclusions: Based on the characteristic of β2M, it or its signaling pathway has been targeted as biomedical or therapeutic tools. Moreover, β2M is highly conserved among different species, and overall structures are virtually identical, implying the versatility of β2M on applications.

A cable-suspended parallel mechanism for full rolling motion of moving platform is designed, a kinematic mathematical model and a statics model of the mechanism are established, the variation of cable length during full rolling motion at two deflection angles of 0° and 10° are analyzed, by creating a virtual prototype, the distribution of cable tension and the change of centroid displacement of the moving platform are analyzed. The research results will provide a new technical scheme for full rolling of moving platform.

Introduction One hallmark symptom of post‐traumatic stress disorder (PTSD) is an inability to restrict fear responses to the appropriate predictor. An infusion of glucocorticoids (GCs) after a high‐intensity shock has been shown to induce PTSD‐like memory impairments. In addition to GCs, noradrenergic signalling is also recognized as a key biomarker underlying PTSD symptomatology. Methods To explore the role of the noradrenergic system in PTSD‐like memory impairments, in this study, various doses of the β‐adrenoceptor antagonist propranolol were systemically or bilaterally injected into the dorsal hippocampus immediately after unpaired cue‐shock contextual fear conditioning, and then the rats were tested 24 h later. Results Interestingly, we found that only low‐dose propranolol could induce PTSD‐like memory impairments, as rats showed reduced freezing to the correct predictor and generalized fear responses to the safe cues, accompanied by increased NE levels in the hippocampus and altered neural activity within the frontal‐subcortical circuit. Conclusion These findings demonstrate that the noradrenergic system is involved in regulating the consolidation of contextual fear memory and that propranolol can dose‐dependently induce PTSD‐like memory impairments.

Low cycle fatigue (LCF) behavior of a single crystal superalloy was investigated at 760 °C. Microstructure evolution and fracture mechanism were studied by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), respectively. The results show that the fatigue data fluctuation was small and the fatigue parameters of the alloy had been determined. On increasing the cyclic number, the alloy initially showed slight cyclic softening at the early two or three cycles and slowly hardened to some extent afterwards, then kept stable for the most of the remaining fatigue life. The LCF of the alloy at 760 °C can be attributed to the main elastic damage in fatigue processing. The initiation site of fatigue crack was at or near the surface of the samples. Crack propagated perpendicularly to the loading direction at first and then along {111} octahedral slip planes. The fatigue fracture mechanism was quasi-cleavage fracture. The γ′ phase morphology still maintained cubic shape after fracture. There were a number of slip bands shear the γ′ precipitates and γ matrix near the fracture surface of the specimen. The inhomogeneous deformation microstructure was developed by dislocation motion of cross-slip and a limited γ′ precipitate shearing by slip band, stacking faults or single dislocation was observed.

With its unique migration operator and mutation operator, Biogeography-Based Optimization (BBO), which simulates migration of species in natural biogeography, is different from existing evolutionary algorithms, but it has shortcomings such as poor convergence precision and slow convergence speed when it is applied to solve complex optimization problems. Therefore, we put forward a Cooperative Coevolutionary Biogeography-Based Optimizer (CBBO) in this paper. In CBBO, the whole population is divided into multiple sub-populations first, and then each subpopulation is evolved with an improved BBO separately. The fitness evaluation of habitats of a subpopulation is conducted by constructing context vectors with selected habitats from other sub-populations. Our CBBO tests are based on 13 benchmark functions and are also compared with several other evolutionary algorithms. Experimental results demonstrate that CBBO is able to achieve better results than other evolutionary algorithms on most of the benchmark functions.

The single crystal superalloy with [001] orientation were prepared by screw selecting method in the directionally solidified furnace. Three different melting temperature 1570°C, 1620°C and 1670°C were used in the melting process, respectively. The long term aging of the specimens after full heat treatment were performed at 1100°C for 800 h. The effect of melting temperature on the microstructure stability of the alloy was investigated. The results showed that the primary dendrite arm spacing of alloy decreased with the increasing of melting temperature. The size of γ′ phase particles in these two regions decreases and cubic shape of those turns a little regular with increasing of melting temperature. The difference of γ′ size between the dendrite core and the interdendritic region reduces. The size of γ′ phase particles after heat treatment decreases with increasing of melting temperature. The extent of elements segregation decreases with increasing of melting temperature. The needle shaped TCP phases have already been observed in all of specimens and the amount of TCP phases decreases with increasing of melting temperature. Increase melting temperature of the single crystal superalloy with high refractory content can increase high temperature phase stability.

Differences among SNP panels for individual identification in SNP-selecting and populations led to few common SNPs, compromising their universal applicability. To screen all universal SNPs, we performed a genome-wide SNP mining in multiple populations based on HapMap and 1000Genomes databases. SNPs with high minor allele frequencies (MAF) in 37 populations were selected. With MAF from ≥0.35 to ≥0.43, the number of selected SNPs decreased from 2769 to 0. A total of 117 SNPs with MAF ≥0.39 have no linkage disequilibrium with each other in every population. For 116 of the 117 SNPs, cumulative match probability (CMP) ranged from 2.01 × 10–48 to 1.93 × 10–50 and cumulative exclusion probability (CEP) ranged from 0.9999999996653 to 0.9999999999945. In 134 tested Han samples, 110 of the 117 SNPs remained within high MAF and conformed to Hardy-Weinberg equilibrium, with CMP = 4.70 × 10–47 and CEP = 0.999999999862. By analyzing the same number of autosomal SNPs as in the HID-Ion AmpliSeq Identity Panel, i.e. 90 randomized out of the 110 SNPs, our panel yielded preferable CMP and CEP. Taken together, the 110-SNPs panel is advantageous for forensic test, and this study provided plenty of highly informative SNPs for compiling final universal panels.

a b s t r a c t The quality of senesced leaves is a strong driver for litter decomposition and nutrient cycling in terrestrial ecosystems. The effects of global change factors and ecosystem management strategies on nutrients and stoichiometry of mature leaves have been well established. In contrast, we still know little about their effects on the quality of senesced leaves, which would be different from that of mature leaves due to the occurrence of nutrient resorption during leaf senescence. We examined the effects of nitrogen (N) addition (5.25 g N m −2 yr −1 ), prescribed fire (with four frequencies, including no burning and burning every 1, 2, 4 years), and their interactions on N and phosphorus (P) concentrations and N:P ratios in senesced leaves of five dominant species in a temperate steppe of northern China. Nutrient concentrations and N:P ratios of senesced leaves varied substantially among the five species. Nitrogen addition increased N concentrations and N:P ratios but had no significant effect on P concentrations. Fire significantly increased N and P concentrations and N:P ratios in senesced leaves across all species. The effects of fire depended on its frequency. There was no interaction between N addition and fire in affecting nutrient concentrations and stoichiometry of senesced leaves. Our results suggested that N addition and fire can potentially alter litter quality by changing senesced leaves nutrient status and stoichiometric ratios, with an indirect effect on litter decomposition and ecosystem nutrient cycling in the grassland ecosystems.

Background and Purpose Cerebrovascular remodelling is one of the important risk factors of stroke. The underlying mechanisms are unclear. Integrin β3 and volume-regulated ClC-3 Cl− channels have recently been implicated as important contributors to vascular cell proliferation. Therefore, we investigated the role of integrin β3 in cerebrovascular remodelling and related Cl− signalling pathway. Experimental Approach Cl− currents were recorded using a patch clamp technique. The expression of integrin β3 in hypertensive animals was examined by Western blot and immunohistochemisty. Immunoprecipitation, cDNA and siRNA transfection were employed to investigate the integrin β3/Src/ClC-3 signalling. Key Results Integrin β3 expression was up-regulated in stroke-prone spontaneously hypertensive rats, 2-kidney 2-clip hypertensive rats and angiotensin II-infused hypertensive mice. Integrin β3 expression was positively correlated with medial cross-sectional area and ClC-3 expression in the basilar artery of 2-kidney 2-clip hypertensive rats. Knockdown of integrin β3 inhibited the proliferation of rat basilar vascular smooth muscle cells induced by angiotensin II. Co-immunoprecipitation and immunofluorescence experiments revealed a physical interaction between integrin β3, Src and ClC-3 protein. The integrin β3/Src/ClC-3 signalling pathway was shown to be involved in the activation of volume-regulated chloride channels induced by both hypo-osmotic stress and angiotensin II. Tyrosine 284 within a concensus Src phosphorylation site was the key point for ClC-3 channel activation. ClC-3 knockout significantly attenuated angiotensin II-induced cerebrovascular remodelling. Conclusions and Implications Integrin β3 mediates cerebrovascular remodelling during hypertension via Src/ClC-3 signalling pathway.

In the title compound, C21H21F2N3O4S, the tetrahydrofuran ring adopts an envelope conformation with the β-C atom positioned at the flap. The triazole, difluorophenyl and tolyl rings of the various substituents on the tetrahydrofuran ring are inclined at 77.88 (12), 83.81 (10) and 81.00 (10)°, respectively, to the best-fit mean plane through the five atoms of the tetrahydrofuran ring. In the crystal, weak C—H...O and C—H...F hydrogen bonds link the molecules into a three-dimensional structure, with molecules stacked along thea-axis direction.

Aims The ClC-3 chloride channel (and current, I Cl,ClC-3) plays an important role in cell volume regulation, proliferation, and apoptosis in vascular smooth muscle cells, and is a potential target for prevention of vascular remodelling and stroke. However, modulation of I Cl,ClC-3 by intercellular signalling is not fully understood. Although it has been suggested that tyrosine phosphorylation is required for I Cl,ClC-3 activation, the potential tyrosine residues in the ClC-3 protein are not clear. In the present study, the critical tyrosine residues in ClC-3 protein were investigated. Methods and results Site-specific mutagenesis, immunoprecipitation, patch clamp, and Cl− transport imaging techniques were employed. We found that activation of I Cl,ClC-3 was associated with tyrosine phosphorylation of the ClC-3 protein. Three potential tyrosine residues, Y284, Y572, and Y631, were mutated to phenylalanine, and only mutation, at Y284 within a consensus Src-phosphorylation site, completely blocked I Cl,ClC-3. Phosphomimetic mutation Y284D increased the Cl− current and Cl− efflux mediated by ClC-3. The Y284F mutation completely abolished the protective effect of ClC-3 on apoptosis, whereas the Y284D mutation potentiated it. There was an interaction between Src kinase and ClC-3 protein, and the Y284D mutation abrogated the inhibitory effect of SU6656, a Src family kinase inhibitor, on ClC-3 Cl− current. Conclusion Tyrosine 284 phosphorylation in the ClC-3 channel targeted by Src kinase is an important molecular mechanism for ClC-3 channel activation.

Five physiological and eleven yield traits of two pairs of sister lines generated from a high generation with similar genetic background (SLs) for purple pericarp were investigated to explore the reasons behind low-yield production of colored rice. Of the five physiological traits examined, except grain anthocyanin content, there were generally similar trends between the P (purple-pericarp) lines and the corresponding W (white-pericarp) lines over two seasons (in the year 2009 and 2010 separately). The results demonstrated that the chlorophyll content of flag leaves, the net photosynthetic rate of flag leaves, and the grain anthocyanin content could be easily influenced by the environment. The physiological functions of the traits for the P lines were more active than those of the corresponding W lines in the year 2010. The grain anthocyanin content of the P lines was much greater in the year 2010 than in the year 2009 during the growth period. The investigation of yield traits revealed that the P lines had reduced 1000-grain weight, yield per plot and grain/brown rice thickness compared to the W lines. A difference comparison of these traits and a source-sink and transportation relationship analysis for these SLs suggested that small sink size was a key reason behind yield reduction of purple pericarp rice.

Statins have pleiotropic actions against the development of vascular remodeling and the incidence of ischemic stroke. Although previous studies have suggested that posttranslational modification of several proteins, such as Rho by mevalonate-derived isoprene groups, geranylgeranyl pyrophosphate or farnesyl pyrophosphate, underlie the pleiotropic effects of statins, the detailed mechanisms remain elusive. Recent growing evidence demonstrated that ClC-3 volume-regulated chloride channel plays an important role in cell proliferation, and the activity of this channel is increased in basilar smooth muscle cells from a hypertensive rat. We hypothesized that inhibition of volume-regulated chloride channel may contribute to the beneficial effects of statins on cerebrovascular remodeling during hypertension. Our study here demonstrated that simvastatin ameliorated hypertension-caused cerebrovascular remodeling. In rat basilar smooth muscle cells, simvastatin inhibited cell proliferation and activation of volume-regulated chloride channel, and these effects of simvastatin were abolished by pretreatment with mevalonate or geranylgeranyl pyrophosphate. In addition, Rho A inhibitor C3 exoenzyme and Rho kinase inhibitor Y-27632 both reduced cell proliferation and activation of volume-regulated chloride channel. Moreover, ClC-3 overexpression decreased the suppressive effect of simvastatin on cell proliferation and increased estimated IC 50 of simvastatin on endothelin 1- and hypo-osmolarity-induced cell proliferation from 3.40±0.08 and 3.50±0.10 μmol/L to 5.30±0.70 and 5.60±0.70 μmol/L, respectively ( P

The inheritance of purple pericarp was studied through genetic analysis using F2, BC1F1 and F3 from a cross between a purple pericarp rice variety Zixiangnuo and a white pericarp rice variety Chunjiangnuo 2. Seven pairs of near isogenic lines (NILs) for pericarp color of rice were further constructed. Genetic analysis indicated that the purple pericarp was controlled by two complementary genes (Pb and Pp). Agronomic trait analysis and polymorphism analysis using SSR markers on these seven pairs of NILs were used in the evaluation of near-isogenicity. No significant differences in agronomic traits were found except 1000-grain weight between the NILs. The polymorphic SSR markers for the parents were only detected in target segments of the five pairs of NILs different in Pb, which revealed the ideal near isogenicity of them. However, for the two pairs of NILs different in Pp, the polymorphic markers for the two parents were detected as well as in non-targeted segments of chromosomes 11 and 12, respectively.

On 26 April 1999, three persons were accidentally exposed by high dose (60)Co irradiation. They suffered from severe (one case) or moderate (two cases) hemopoietic form of acute radiation sickness (ARS). As part of the comprehensive treatment, strict reverse isolation and granulocyte-macrophage colony-stimulating factor (GM-CSF) therapy were applied. All the patients recovered after an appropriate treatment for 83 days. In our experience, the correct diagnosis and effective treatment at an early stage proved to be helpful to the patients in pulling out from the critical stage of acute radiation sickness. To avoid menstruation by the female patient just in the critical stage, we modified her menstruation cycle by testosterone. In our view, GM-CSF should be given as early as possible with enough dosage for promoting early hematological reconstruction. The experience obtained from the medical management of these patients is valuable for the treatment of such patients in the future.

A 6A,6A′-dicyclohexylamine-6B,6B′-diselenide-bis-β-cyclodextrin (6-CySeCD) was designed and synthesized to imitate the antioxidant enzyme glutathione peroxidase (GPX). In this novel GPX model, β-cyclodextrin provided a hydrophobic environment for substrate binding within its cavity, and a cyclohexylamine group was incorporated into cyclodextrin in proximity to the catalytic selenium in order to increase the stability of the nucleophilic intermediate selenolate. 6-CySeCD exhibits better GPX activity than 6,6′-diselenide-bis-cyclodextrin (6-SeCD) and 2-phenyl-1,2-benzoisoselenazol-3(2H)-one (Ebselen) in the reduction of H2O2, tert-butyl hydroperoxide and cumenyl hydroperoxide by glutathione, respectively. A ping-pong mechanism was observed in steady-state kinetic studies on 6-CySeCD-catalyzed reactions. The enzymatic properties showed that there are two major factors for improving the catalytic efficiency of GPX mimics. First, the substrate-binding site should match the size and shape of the substrate and second, incorporation of an imido-group increases the stability of selenolate in the catalytic cycle. More efficient antioxidant ability compared with 6-SeCD and Ebselen was also seen in the ferrous sulfate/ascorbate-induced mitochondria damage system, and this implies its prospective therapeutic application.