788 research outputs found
The effect of calcium on auxin depletion-induced tomato (Lycopersicon esculentum Mill.) pedicel abscission
Indole-3-acetic acid (IAA) and calcium are the most important factors that instigate plant organ abscission. This study aimed to elucidate the mechanisms that underlie the effects of IAA and calcium on delayed abscission in tomato. The results showed a clear trend towards reduced abscission rates with increased concentrations of IAA, and the applications on pedicel proximal or distal side also resulted in a different abscission. IAA combined with calcium significantly improved inhibition in contrast to IAA only, while IAA combined with magnesium exhibited little increased inhibition. 1-NNaphthylphthalamic acid (NPA), a polar auxin transport inhibitor, accelerated the abscission. IAA transported basipetally through an assay with 4 mm long pedicel sections indicated that the average transport intensity of [3H]-IAA applied to the distal pedicel end was 65 Bq hâ1 and the average velocity was 5.29 mm h-1. When the proximal side was incubated in [3H]-IAA, its average transport intensity reduced to 19.53 Bq hâ1 and the average velocity was only 1.92 mm h-1. Calcium treatment enhanced IAA transportation, as shown by significantly enhancing the transport intensity, but it had no effect on velocity.Keywords: Indole-3-acetic acid (IAA), calcium, abscission, tomat
Traditional Chinese medicinal formula Si-Wu-Tang prevents oxidative damage by activating Nrf2-mediated detoxifying/antioxidant genes
BACKGROUND: Induction of Nrf2-mediated detoxifying/antioxidant genes has been recognized as an effective strategy for cancer chemoprevention. Si-Wu-Tang (SWT), comprising the combination of four herbs, Paeoniae, Angelicae, Chuanxiong and Rehmanniae, is one of the most popular traditional oriental medicines for womenâs diseases. The purpose of this study is to determine the effects of SWT on Nrf2 pathway in vitro and in vivo and to identify the active component(s). RESULTS: Cell viability and apoptosis were analyzed in the non-cancerous breast epithelial cell line MCF-10A after H(2)O(2) treatment in the presence or absence of SWT using the Sulphorhodamine B assay, Annexin-V/Propidium iodide staining and flow cytometry. SWT strongly reduced H(2)O(2) -induced cytotoxicity and apoptosis in MCF-10A cells. Expression of Nrf2 and Nrf2-regulated genes HMOX1 (heme oxygenase 1) and SLC7A11 (xCT) was evaluated by quantitative RT-PCR, Western Blot and immunocytochemistry. SWT strongly induced Nrf2-regulated genes at mRNA and protein levels and increased the nuclear translocation of Nrf2 in MCF-10A cells. The in vivo pharmacodynamic effect of SWT was evaluated in healthy female SpragueâDawley rats. Short-term oral administration of SWT (1,000Â mg/kg per day for six consecutive days) to rats resulted in an increased expression of Nrf2-regulated genes Hmox1 and Slc7A11 in the liver detected by quantitative RT-PCR. Among nine compounds that have been identified previously in the SWT products, z-liguistilide was discovered as the main component responsible for the effect of Nrf2 activation using the antioxidant response element-luciferase reporter gene assay. Z-liguistilide was confirmed with a high potency to induce Nrf2-regulated genes and Nrf2 nuclear translocation. CONCLUSIONS: Our results demonstrated that SWT and its component z-liguistilide are able to activate the Nrf2 pathway in non-cancerous cells and organs in vitro and in vivo, suggesting that SWT might be an orally effective and nontoxic agent for cancer chemoprevention
Thermodynamics of deformed AdS model with a positive/negative quadratic correction in graviton-dilaton system
By solving the Einstein equations of the graviton coupling with a real scalar
dilaton field, we establish a general framework to self-consistently solve the
geometric background with black-hole for any given phenomenological holographic
models. In this framwork, we solve the black-hole background, the corresponding
dilaon field and the dilaton potential for the deformed AdS model with a
positive/negative quadratic correction. We systematically investigate the
thermodynamical properties of the deformed AdS model with a positive and
negative quadratic correction, respectively, and compare with lattice QCD on
the results of the equation of state, the heavy quark potential, the Polyakov
loop and the spatial Wilson loop. We find that the bulk thermodynamical
properties are not sensitive to the sign of the quadratic correction, and the
results of both deformed holographic QCD models agree well with lattice QCD
result for pure SU(3) gauge theory. However, the results from loop operators
favor a positive quadratic correction, which agree well with lattice QCD
result. Especially, the result from the Polyakov loop excludes the model with a
negative quadratic correction in the warp factor of .Comment: 26 figures,36 pages,V.3: an appendix,more equations and references
added,figures corrected,published versio
Strong convergence for total quasi-Ď-asymptotically nonexpansive semigroups in Banach spaces
Genome-wide copy number variation study in anorectal malformations
Anorectal malformations (ARMs, congenital obstruction of the anal opening) are among the most common birth defects requiring surgical treatment (2-5/10 000 live-births) and carry significant chronic morbidity. ARMs present either as isolated or as part of the phenotypic spectrum of some chromosomal abnormalities or monogenic syndromes. The etiology is unknown. To assess the genetic contribution to ARMs, we investigated single-nucleotide polymorphisms and copy number variations (CNVs) at genome-wide scale. A total of 363 Han Chinese sporadic ARM patients and 4006 Han Chinese controls were included. Overall, we detected a 1.3-fold significant excess of rare CNVs in patients. Stratification of patients by presence/absence of other congenital anomalies showed that while syndromic ARM patients carried significantly longer rare duplications than controls (P = 0.049), non-syndromic patients were enriched with both rare deletions and duplications when compared with controls (P = 0.00031). Twelve chromosomal aberrations and 114 rare CNVs were observed in patients but not in 868 controls nor 11 943 healthy individuals from the Database of Genomic Variants. Importantly, these aberrations were observed in isolated ARM patients. Gene-based analysis revealed 79 genes interfered by CNVs in patients only. In particular, we identified a de novo DKK4 duplication. DKK4 is a member of the WNT signaling pathway which is involved in the development of the anorectal region. In mice, Wnt disruption results in ARMs. Our data suggest a role for rare CNVs not only in syndromic but also in isolated ARM patients and provide a list of plausible candidate genes for the disorder.postprin
Observation of a ppb mass threshoud enhancement in \psi^\prime\to\pi^+\pi^-J/\psi(J/\psi\to\gamma p\bar{p}) decay
The decay channel
is studied using a sample of events collected
by the BESIII experiment at BEPCII. A strong enhancement at threshold is
observed in the invariant mass spectrum. The enhancement can be fit
with an -wave Breit-Wigner resonance function with a resulting peak mass of
and a
narrow width that is at the 90% confidence level.
These results are consistent with published BESII results. These mass and width
values do not match with those of any known meson resonance.Comment: 5 pages, 3 figures, submitted to Chinese Physics
Reaction rates and transport in neutron stars
Understanding signals from neutron stars requires knowledge about the
transport inside the star. We review the transport properties and the
underlying reaction rates of dense hadronic and quark matter in the crust and
the core of neutron stars and point out open problems and future directions.Comment: 74 pages; commissioned for the book "Physics and Astrophysics of
Neutron Stars", NewCompStar COST Action MP1304; version 3: minor changes,
references updated, overview graphic added in the introduction, improvements
in Sec IV.A.
A hQCD model and its phase diagram in Einstein-Maxwell-Dilaton system
By use of the potential reconstruction approach we obtain a series of
asymptotically AdS (aAdS) black hole solutions in an Einstein-Maxwell-Dilaton
(EMD) system. Basing on the solutions of the system, we reconstruct a
semi-analytical holographic QCD (hQCD) model with a quadratic term in warped
factor. We discuss some aspects of the hQCD model, in particular we calculate
the free energy of two static color sources (a heavy quark-antiquark pair)
which is an important order parameter to describe confinement/deconfinement
phase transition. The behavior of the free energy with respect to temperature
and chemical potential is studied. We find that in the hQCD model the
deconfinement phase transition can be realized and a critical point occurs. The
resulting phase diagram in the temperature-chemical potential plane is
in quite good agreement with the one from recent lattice results and effective
models of QCD.Comment: 27 pages, 11 figures, regular paper, add some comments and
references, accepted by JHE
High prevalence of hyperglycaemia and the impact of high household income in transforming Rural China
<p>Abstract</p> <p>Background</p> <p>The prevalence of hyperglycaemia and its association with socioeconomic factors have been well studied in developed countries, however, little is known about them in transforming rural China.</p> <p>Methods</p> <p>A cross-sectional study was carried out in 4 rural communities of Deqing County located in East China in 2006-07, including 4,506 subjects aged 18 to 64 years. Fasting plasma glucose (FPG) was measured. Subjects were considered to have impaired fasting glucose (IFG) if FPG was in the range from 5.6 to 6.9 mmol/L and to have diabetes mellitus (DM) if FG was 7.0 mmol/L or above.</p> <p>Results</p> <p>The crude prevalences of IFG and DM were 5.4% and 2.2%, respectively. The average ratio of IFG/DM was 2.5, and tended to be higher for those under the age of 35 years than older subjects. After adjustment for covariates including age (continuous), sex, BMI (continuous), smoking, alcohol drinking, and regular leisure physical activity, subjects in the high household income group had a significantly higher risk of IFG compared with the medium household income group (OR: 1.74, 95% CI: 1.11-2.72) and no significant difference in IFG was observed between the low and medium household income groups. Education and farmer occupation were not significantly associated with IFG.</p> <p>Conclusions</p> <p>High household income was significantly associated with an increased risk of IFG. A high ratio of IFG/DM suggests a high risk of diabetes in foreseeable future in the Chinese transforming rural communities.</p
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