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The present study investigated the effects of glutamine (GLN) pretreatment on CD4+ T cell polarisation and remote kidney injury in mice with gut-derived polymicrobial sepsis. Mice were randomly assigned to three groups: normal control fed with American Institute of Nutrition (AIN)-93G diet and two sepsis groups provided with either AIN-93G-based diet or identical components, except part of casein was replaced by GLN. Mice were given their respective diets for 2 weeks. Then, mice in the sepsis groups were performed with caecal ligation and puncture and were killed 72 h after the surgery. Blood, spleens and kidneys were collected for further examination. The results showed that sepsis resulted in decreased circulating and splenic total T lymphocyte and CD4+ T cell percentages, whereas IL-4-, and forkhead box p3 (Foxp3)-expressing CD4+ T cells percentages were up-regulated. Compared with the sepsis control group, pretreatment with GLN maintained blood T and CD4+ T cells and reduced percentages of IL-4- and Foxp3-expressing CD4+ T cells. Also, a more pronounced activation and increased anti-apoptotic Bcl-2 gene expression of splenic CD4+ T cells were observed. Concomitant with the decreased plasma IL-6, keratinocyte-derived chemokine (KC) levels, the gene expression of KC, macrophage inflammatory protein-2 and renal injury biomarker kidney injury molecule-1 (Kim-1) were down-regulated when GLN was administered. These findings suggest that antecedent of GLN administration elicit a more balanced blood T helper cell polarisation, sustained T cell populations, prevented splenic CD4+ T cell apoptosis and attenuated kidney injury at late phase of polymicrobial sepsis. GLN may have benefits in subjects at risk of abdominal infection.
Owing to lack of a definitive correlation between carbon supports and catalytic activity of single-atom Fe-active sites, rational design and preparation of single-atom Fe catalysts have so far been elusive. Herein we designed and prepared one-dimensional core–shell nanostructured single-atom Fe catalysts, in which carbon nanofibers and carbon nanotubes with different crystallinities and electrical conductivities were used as supports to host single-atom Fe-active sites. It was found that the carbon supports with higher electrical conductivity accelerate charge transfer and enhance the oxygen reduction reaction (ORR) activity of single-atom Fe-active sites as well as the ORR durability of the final catalyst.
Good canopy structure is essential for optimal maize (Zea mays L.) production. However, creating appropriate maize canopy structure can be difficult, because the characteristics of individual plants are altered by changes in plant age, density and interactions with neighbouring plants. The objective of the current study was to find a reliable method for building good maize canopy structure by analysing changes in canopy structure, light distribution and grain yield (GY). A modern maize cultivar (ZhengDan958) was planted at 12 densities ranging from 1.5 to 18 plants/m2 at two field locations in Xinjiang, China. At the silking stage (R1), plant and ear height increased with plant density as well as leaf area index (LAI), whereas leaf area per plant decreased logarithmically. The fraction of light intercepted by the plant (F) increased with increasing plant density, but the light extinction coefficient (K) decreased linearly from 0.61 to 0.39. Taking the optimum value of F (95%) as an example, and using measured values of K for each plant density at R1 and the equation from Beer's law, the corresponding (theoretical) LAI for each plant density was calculated and optimum plant density (9.72 plants/m2) obtained by calculating the difference between theoretical LAIs and actual observations. Further analysis showed that plant density ranging from 10.64 to 11.55 plants/m2 yielded a stable GY range. Therefore, taking into account the persistence time for maximum LAI, the plant density required to obtain an ideal GY maize canopy structure should be increased by 10–18% from 9.72 plants/m2.
Suboptimal vitamin B2 status is encountered globally. Riboflavin deficiency depresses growth and results in a fatty liver. The underlying mechanisms remain to be established and an overview of molecular alterations is lacking. We investigated hepatic proteome changes induced by riboflavin deficiency to explain its effects on growth and hepatic lipid metabolism. In all, 360 1-d-old Pekin ducks were divided into three groups of 120 birds each, with twelve replicates and ten birds per replicate. For 21 d, the ducks were fed ad libitum a control diet (CAL), a riboflavin-deficient diet (RD) or were pair-fed with the control diet to the mean daily intake of the RD group (CPF). When comparing RD with CAL and CPF, growth depression, liver enlargement, liver lipid accumulation and enhanced liver SFA (C6 : 0, C12 : 0, C16 : 0, C18 : 0) were observed. In RD, thirty-two proteins were enhanced and thirty-one diminished (>1·5-fold) compared with CAL and CPF. Selected proteins were confirmed by Western blotting. The diminished proteins are mainly involved in fatty acid β-oxidation and the mitochondrial electron transport chain (ETC), whereas the enhanced proteins are mainly involved in TAG and cholesterol biosynthesis. RD causes liver lipid accumulation and growth depression probably by impairing fatty acid β-oxidation and ETC. These findings contribute to our understanding of the mechanisms of liver lipid metabolic disorders due to RD.
High-quality carbon nanotubes (CNTs) and graphene synthesized by chemical vapor deposition (CVD) have unique one- and two-dimensional structures made up of sp2-hybridized carbon atoms and excellent physical and chemical properties. They have shown potential for use in electronics, optoelectronics, energy-storage devices, composites, and sensors. In this article, we review important milestones in these uses of CNTs and graphene produced by CVD, with special emphasis on the latest advances and remaining challenges. The key characteristics and advantages of CNTs and graphene synthesized by CVD for different applications are compared, and future trends in the use of these nanocarbons are discussed.
In this paper, we focus on studying the high energy emission of GRB 160625B. The lightcurve of prompt emission is composed of three episodes: short-soft precursor, hard main burst, and possible long extended emission. The spectra of first and third episode can be fitted by a multi-color blackbody and cutoff power-law model, respectively. However, the spectrum of second episode was contributed by both multi-color blackbody and cutoff power-law. One can estimate the Lorenz factor of jet of first two episodes by invoking photosphere model as Γ0 ~ 175 and 1694, respectively. It suggests that the ejecta of this case evolved from photosphere dominated initially to internal shock later. On the other hand, the optical emission is very bright during the second episode, which is likely a prompt optical emission. Finally, a more shallower normal decay segment appeared, which is consistent with standard external shock model.
There is an ongoing relationship between host plants and herbivores. The nutrient substances and secondary compounds found in the host plant can not only impact the growth and development process of herbivores, but, more importantly, may also affect their survival and reproductive fitness. Vitellogenesis is the core process of reproductive regulation and is generally considered as a reliable indicator for evaluating the degree of ovarian development in females. Vitellogenin (Vg) plays a critical role in the synthesis and secretion of yolk protein. In this study, the full-length cDNA of the Vg gene in an alien invasive species, the nipa palm hispid beetle Octodonta nipae Maulik (Coleoptera: Chrysomelidae) (OnVg) was cloned and, the effect of host plant on the OnVg expression level and ovarian development was investigated. The results revealed that the OnVg was highly and exclusively expressed in adult females, but barely detectable in larvae, pupae and adult males. The relative expression level of OnVg and egg hatchability were much higher in females fed on Phoenix canariensis (their preferred host) than those fed on Phoenix roebelenii. A positive correlation relationship between OnVg expression and egg hatchability was also detected. Additionally, the anatomy of the female reproductive system showed that the ovaries of individuals fed on P. canariensis were considerably more developed than in females fed on P. roebelenii. The results may be applicable to many pest management situations through reproductive disturbance by alternating host plant species or varieties or by reproductive regulation through vitellogenesis mediated by specific endocrine hormones.
The mesoporous and nanorods SnO2 are synthesized by controlling the state of SnCl2·2H2O precursor with SBA-15 as hard template, and the possible formation mechanisms at different assembling modes inside the ordered mesoporous silica templates are proposed. In addition, SnO2 nanoparticles are synthesized by hydrolysis depositing method. The electrochemical tests of as-prepared samples indicate that the reticular stacking structure of the nanorods would limit the Li+ ions to intercalate, but the effect of volume expansion in this case upon cycling is insignificant. The mesostructure SnO2 tends to be stable after partial structural collapse at first few cycles. And the Li+ ions can readily intercalate and de-intercalate into/from its ordered channels structure, which provides a high capacity and an improved cycle property. Although SnO2 nanoparticles deliver high capacity at an early stage, the agglomeration may induce the capacity to drop rapidly after a certain number of cycles.
A novel graphene-modified LiMnPO4 composite as a performance-improved cathode material for lithium-ion batteries has been prepared with LiH2PO4, Mn(CH3COO)2·4H2O, and graphite oxide (GO) suspension by spray-drying method. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and galvanostatic charge–discharge tests are applied to characterize these materials. The structure analysis shows that LiMnPO4 sheets with width of 100–200 nm and thickness of 20–30 nm are attached to the graphene sheets in pieces. The graphene sheets with good electrical conductivity serve as a conducting network for fast electron transfer between the active materials and charge collector, as well as buffered spaces to accommodate the volume expansion/contraction during the discharge/charge process. The electrochemical tests show that the composite cathode material could deliver a capacity of 105.1 mAh/g at 0.05 C in the voltage range of 2.5–4.4 V. Moreover, the cells showed fair good cycle ability over 50 cycles.
The aim of this study was to examine and test the sensitivity, specificity, and threshold scores of the Montreal Cognitive Assessment (MoCA) and the Mini-Mental State Examination (MMSE) and determine those that best correspond to a clinical diagnosis of dementia with Lewy bodies (DLB).
Sixty-seven Alzheimer's disease (AD), 36 DLB, and 62 healthy participants without dementia (NC), aged 60 to 90, were enrolled. All three groups took the MoCA and MMSE tests at the same time. The Cochran–Mantel–Haenszel tests and receiver operating characteristics curve analysis were used to compare the different neuropsychological test results among the groups.
The cut-off point of the MoCA for AD was 21/22 with a sensitivity of 95.5% and a specificity of 82.3% (area under the curve (AUC): 0.945), and the cut-off point for DLB was 22/23 with a sensitivity of 91.7% and a specificity of 80.6% (AUC: 0.932). For the MMSE, the cut-off points for AD and for DLB from NC were all 24/25, with a sensitivity of 88.1% and a specificity of 85.5% for AD (AUC: 0.92), and a sensitivity of 77.8% and a specificity of 85.5% for DLB (AUC: 0.895). After controlling sex, age, and education, AD and DLB had lower scores in all MoCA subscales than the NC group (p < 0.05), except for the orientation and naming in DLB. In addition, AD had a lower score in the MoCA orientation (p = 0.03) and short-term memory (p = 0.02) than did DLB.
The MoCA is a more sensitive instrument than the MMSE to screen AD or DLB patients from non-dementia cases.
Understanding the factors that affect the nesting success of threatened birds is essential in designing effective conservation strategies. Here we compare nesting success of the Reed Parrotbill Paradoxornis heudei in annually harvested and non-harvested reedbed habitats in the Chongming Dongtan Nature Reserve in China, by recording the number of nestlings produced per nest and the causes of nest failure. We modelled daily nest survival rate (DSR) by considering the effects of harvesting, vegetation characteristics, year, date, advancement within the breeding season, nest age and nearest-nest distance, using the program MARK. Nest densities, but not the number of fledglings per nest, were significantly lower in harvested than non-harvested reedbed habitats. The best-fit DSR model estimated constant survival; none of the tested co-variables had significant effects. Moreover, harvesting did not affect the date of breeding initiation, likelihood of nest failure, or causes of nest failure, as vegetation cover was not significantly different between harvested and non-harvested reedbeds during the whole breeding season. Nest failure following adverse weather conditions was unusually common in harvested and non-harvested reedbeds, accounting for as many nest failures as depredation. However, comparisons with other studies suggest that deriving a conclusion on the impact of harvesting on nesting success is not straightforward and is probably linked to environmental characteristics affecting reed growth.
Epistasis underlying fertility plays an important role in crop breeding. Although a new female sterile mutant in wheat, XND126, has been identified and a major quantitative trait locus (QTL), taf1, for the female sterility has been mapped, the genetic architecture of the female sterility needs to be further addressed. To identify the interaction involving the gene(s) controlling the female sterility, an investigation was carried out for the seed setting ratio in an F2 population derived from the cross between XND126 and Gaocheng 8901. Among 1250 simple sequence repeat (SSR) primer pairs in the whole genome, a total of 21 markers, obtained by recessive class approach, along with other ten tightly linked markers on reference maps in wheat, were used to survey 243 F2 individuals. As a result, 28 markers were mapped into five genetic linkage groups. The performance for female sterility for each F2 individual was evaluated simultaneously at the Urumqi and Huai'an experimental stations in 2006–2007. The two phenotypic datasets along with marker information were jointly analysed in the detection of QTL using penalized maximum likelihood approach. A total of six QTLs, including two main-effect QTLs, three epistatic QTLs and one environmental interaction and accounting for 0·67–24·55% of the total phenotypic variance, were identified. All estimated effects accounted for 53·26% of the total phenotypic variation. The taf1 detected in previous study was also located on the same marker interval on chromosome 2DS. These results enrich our understanding of the genetic basis of the female sterility.
The Reed Parrotbill Paradoxornis heudei is an endemic reedbed-inhabiting passerine of east Asia. In the Shanghai municipality, which harbours significant populations of this species, almost all reedbed surfaces are annually harvested. Furthermore, the reedbeds are being invaded by Smooth Cordgrass Spartina alterniflora, an introduced species that can outcompete the native Common Reed Phragmites australis. In this paper, we have shown that Reed Parrotbills do not nest in areas dominated by Smooth Cordgrass and avoid using them. In the areas that are primarily composed of Common Reed, the densities of birds are higher in the unharvested sections. The birds appear to select nesting sites with low Smooth Cordgrass densities, tall reed stems, and relatively equal densities of both dry and green stems. Reed harvesting activity results in vegetation that is too low for bird nesting. However, no nests were found in areas where the reeds had not been harvested for several years and had high densities of dry reed stems; these results could be attributed to the fact that the high density of broken stems reduced the vegetation cover. On the basis of our results, we recommend implementation of four years harvesting-cycle rotation and avoidance of reclamation in reedbeds which have not been invaded by Smooth Cordgrass.
Single-nucleotide polymorphisms (SNPs) of exon 8 of the GHR gene were detected in Chinese Holstein cows by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). The results showed that exon 8 of the GHR gene digested by TasI could be divided into two kinds of alleles and three kinds of genotypes. The frequencies of allele A and T were 0.6339 and 0.3661, respectively. The frequencies of genotypes AA, AT and TT were 0.459, 0.350 and 0.191, respectively. Sequencing showed one single nucleotide mutation T→A at 4962 bp of the gene in genotype TT when compared with genotype AA, and this mutation resulted in an amino acid change of phenylalanine (TTT)→tyrosine (TAT). The result of χ2 testing indicated that the genotypic frequency of the GHR gene digested by TasI did not fit with Hardy–Weinberg equilibrium in this population (P<0.05). The least-square mean of the fat percentage of this population was higher for genotype TT than for genotype AA (P<0.05).
To evaluate the effect on decrease in blood pressure of modifying risk factors for stroke, such as blood lipid profiles, diet habits and indices of body weight, through a family-based nutrition health education programme among hypertensive patients and pre-hypertensive subjects without taking any antihypertensive drugs.
Design and setting
This was a community-based prospective study. The study population was randomly selected from communities in Taipei; potential subjects were invited by telephone to participate.
After excluding subjects whose blood pressure was normal and those using antihypertensive drugs, there were 390 participants included in the study. Subjects in the intervention group (n 293) received nutrition health education on blood pressure control and stroke-related risk factor modification at each visit. Non-intervention subjects (n 97) only acquired a general education sheet available in clinics. The blood pressure of study subjects was measured at baseline and 6-month follow-up to evaluate the intervention’s effect on decrease in blood pressure.
Significant decreases of 2·0 mmHg and 5·9 mmHg in systolic blood pressure were observed both in pre-hypertensive and hypertensive subjects in the intervention group. Additionally, intervention subjects with improvement of total cholesterol and LDL cholesterol, decrease in indices of body weight and increase in consumption of fruit and vegetables also had significant lowering of blood pressure.
The present study provided evidence that the blood pressure of pre-hypertensive and hypertensive subjects could decrease significantly, without taking antihypertensive drugs, after modifying blood lipid profiles and waist by dietary habits changed through a family-based nutrition heath education programme, resulting in a significant effect on stroke risk reduction.
Diabetes mellitus is an important risk factor for CVD. A previous study showed that high glucose induced the apoptosis of human umbilical vein endothelial cells (HUVEC) via the sequential activation of reactive oxygen species, Jun N-terminal kinase (JNK) and caspase-3. The apoptosis cascade could be blocked by ascorbic acid at the micromolar concentration (100 μm). In addition to ascorbic acid, quercetin, the most abundant dietary flavonol, has been recently actively studied in vascular protection effects due to its antioxidant effect at low micromolar concentrations (10–50 μm). Quercetin sulfate/glucuronide, the metabolite of quercetin in blood, however, has been rarely evaluated. In the present study, we investigated the effect of quercetin sulfate/glucuronide on the prevention of high glucose-induced apoptosis of HUVEC. HUVEC were treated with media containing high glucose (33 mm) in the presence or absence of ascorbic acid (100 μm) or quercetin sulfate/glucuronide (100 nm, 300 nm and 1 μm). For the detection of apoptosis, a cell death detection ELISA assay was used. The level of intracellular H2O2 was measured by flow cytometry. JNK and caspase-3 were evaluated by a kinase activity assay and Western blot analysis. The results showed that high glucose-induced apoptosis was inhibited by quercetin sulfate/glucuronide in a dose-dependent manner. The effect of quercetin sulfate/glucuronide on H2O2 quenching, inhibition of JNK and caspase-3 activity at the nanomolar concentration (300 nm) was similar to that of ascorbic acid at the micromolar concentration (100 μm). The findings of the present study may shed light on the pharmacological application of quercetin in CVD.
Two suites of granitoids, the Late Jurassic (158 ± 3 Ma) Linglong suite and the Early Cretaceous (130–126 Ma) Guojialing suite, crop out in the northwestern Jiaodong Peninsula, eastern China. The Linglong suite is a monzogranite, comprising alkali feldspar, plagioclase, quartz and Fe-rich biotite. The Guojialing suite includes at least five plutonic bodies of both granodiorite and monzo-granite. The rocks are composed of plagioclase, alkali feldspar, quartz, Mg-rich amphibole and Mg-rich biotite. Both the Linglong and Guojialing suites have adakitic affinity. They are enriched in LREE with high La/Yb ratios and show positive Eu anomalies. The rocks are also enriched in LILE and depleted in HFSE with high Sr/Y ratios. The Linglong granite shows very uniform Sr–Nd isotopic compositions with initial 87Sr/86Sr ratios of 0.7119–0.7126 and εNd (T) values of −21.3 to −21.6, which are similar to those of the local Neoarchaean basement. The Guojialing suite has variable initial 87Sr/86Sr ratios (0.7108–0.7120) and εNd (T) values (−10.8 to −17.2), which are distinct both from those of the Neoarchaean basement and from those of the local enriched lithospheric mantle inferred from the coeval mafic dykes in the studied area. Detailed petrological and geochemical data indicate that the Linglong suite was derived by partial melting of Neoarchaean metamorphic lower-crustal rocks at depth of > 50 km with a eclogite residue, whereas the Guojialing suite was formed by the reaction of delaminated eclogitic crust-derived melt with the upwelling asthenospheric mantle. The petrogenesis of these two contrasting adakitic granitoids suggests intensive lower-crustal delamination during Early Cretaceous times, following a crustal thickening process from the late stage of the Early Jurassic to early stage of the Late Jurassic with crustal thickness of < 32 km to > 50 km, respectively.
The present study was designed to examine whether in vitro produced porcine embryos can be used to establish an embryonic stem (ES) cell line. Porcine embryos were produced by in vitro maturation and in vitro fertilization. Embryos at the 4-cell to blastocyst stages were cultured in an ES medium containing 16% fetal bovine serum with mouse embryonic fibroblasts as a feeder layer. It was found that ES-like colonies were derived only from blastocysts. When these ES-like colonies were separated in 0.25% trypsin–0.02% EDTA solution and cultured again, ES-like colonies were further observed in the subsequent culture until the fourth passage. The cells from ES-like colonies showed positive alkaline phosphatase activity. Some cells from the colonies differentiated into several types of cells in vitro when they were cultured in the medium without feeder layers and leukemin inhibitory factor. Embryoid bodies were also formed when the cells were cultured in a suspension status. These results indicate that porcine ES-like cells can be derived from in vitro produced porcine blastocysts and these ES-like cells are pluripotent. The culture system used in the present study is useful to isolate and culture ES cells from in vitro produced porcine embryos.
Aminoacyl-tRNA synthetases attach amino acids to the 3′
termini of cognate tRNAs to establish the specificity of protein
synthesis. A recent Asilomar conference (California, January
13–18, 2002) discussed new research into the
structure–function relationship of these crucial enzymes,
as well as a multitude of novel functions, including participation
in amino acid biosynthesis, cell cycle control, RNA splicing,
and export of tRNAs from nucleus to cytoplasm in eukaryotic
cells. Together with the discovery of their role in the cellular
synthesis of proteins to incorporate selenocysteine and
pyrrolysine, these diverse functions of aminoacyl-tRNA synthetases
underscore the flexibility and adaptability of these ancient
enzymes and stimulate the development of new concepts and methods
for expanding the genetic code.
RNA helices that recapitulate sequences of the
tRNA acceptor stem, including the 3′ NCCA nucleotides,
can be substrates for aminoacyl–tRNA synthetases
(Frugier et al., 1994; Hamann & Hou, 1995; Martinis
& Schimmel, 1995; Quinn et al., 1995). Although the
catalytic efficiency of aminoacylation of RNA helices is
reduced from that of the full-length parent tRNA, the specificity
is maintained. The specific aminoacylation lies in the
ability of aminoacyl–tRNA synthetases to recognize
functional groups within the RNA helices. Analysis of tRNA–synthetase
structures has suggested a general principle (Rould et
al., 1989; Ruff et al., 1991; Arnez & Moras, 1997).
The class I synthetases, which attach an amino acid initially
to the 2′-OH of the terminal ribose, approach the
acceptor and NCCA end from the minor groove side. The class
II synthetases, which attach an amino acid to the terminal
3′-OH, approach from the major groove side (Arnez
& Moras, 1997). The class-specific approach leads to
tRNA–synthetase complexes that are near mirror images
of each other and provides a structural rationale for the
stereochemistries of aminoacylation. We report here the
identification of a functional group in the acceptor end
of Escherichia coli tRNACys that is
important for the class I cysteine–tRNA synthetase.
This functional group makes one of the largest energetic
contributions to aminoacylation. However, it is located
on the major groove side of the acceptor stem. Kinetic
analysis of the contribution of this functional group to
aminoacylation suggests new features that are not anticipated
from the class-specific approach of synthetases.