IKKβ Regulates the Repair of DNA Double-Strand Breaks Induced by Ionizing Radiation in MCF-7 Breast Cancer Cells

Activation of the IKK-NFκB pathway increases the resistance of cancer cells to ionizing radiation (IR). This effect has been largely attributed to the induction of anti-apoptotic proteins by NFκB. Since efficient repair of DNA double strand breaks (DSBs) is required for the clonogenic survival of irradiated cells, we investigated if activation of the IKK-NFκB pathway also regulates DSB repair to promote cell survival after IR. We found that inhibition of the IKK-NFκB pathway with a specific IKKβ inhibitor significantly reduced the repair of IR-induced DSBs in MCF-7 cells. The repair of DSBs was also significantly inhibited by silencing IKKβ expression with IKKβ shRNA. However, down-regulation of IKKα expression with IKKα shRNA had no significant effect on the repair of IR-induced DSBs. Similar findings were also observed in IKKα and/or IKKβ knockout mouse embryonic fibroblasts (MEFs). More importantly, inhibition of IKKβ with an inhibitor or down-regulation of IKKβ with IKKβ shRNA sensitized MCF-7 cells to IR-induced clonogenic cell death. DSB repair function and resistance to IR were completely restored by IKKβ reconstitution in IKKβ-knockdown MCF-7 cells. These findings demonstrate that IKKβ can regulate the repair of DSBs, a previously undescribed and important IKKβ kinase function; and inhibition of DSB repair may contribute to cance cell radiosensitization induced by IKKβ inhibition. As such, specific inhibition of IKKβ may represents a more effective approach to sensitize cancer cells to radiotherapy

Search for Kaluza-Klein Graviton Emission in ppˉp\bar{p} Collisions at s=1.8\sqrt{s}=1.8 TeV using the Missing Energy Signature

We report on a search for direct Kaluza-Klein graviton production in a data sample of 84 ${pb}^{-1}$ of \ppb collisions at $\sqrt{s}$ = 1.8 TeV, recorded by the Collider Detector at Fermilab. We investigate the final state of large missing transverse energy and one or two high energy jets. We compare the data with the predictions from a $3+1+n$-dimensional Kaluza-Klein scenario in which gravity becomes strong at the TeV scale. At 95% confidence level (C.L.) for $n$=2, 4, and 6 we exclude an effective Planck scale below 1.0, 0.77, and 0.71 TeV, respectively.Comment: Submitted to PRL, 7 pages 4 figures/Revision includes 5 figure

Comparative efficacies of different antibiotic treatments to eradicate nontypeable Haemophilus influenzae infection

<p>Abstract</p> <p>Background</p> <p>Nonencapsulated and nontypeable <it>Haemophilus influenzae </it>(NTHi) is a major cause of human respiratory tract infections. Some strains of NTHi can cause invasive diseases such as septicemia and meningitis, even if <it>H. influenzae </it>is not generally considered to be an intracellular pathogen. There have been very few reports about the therapeutic efficacy of antibiotics against respiratory tract infection caused by NTHi in mice because it is difficult for <it>H. influenzae </it>to infect mice. Therefore, we evaluated the efficacy of antibiotics against NTHi in both a cell culture model and a mouse model of infection.</p> <p>Methods</p> <p>We used six strains of NTHi isolated from adult patients with chronic otitis media, namely three β-lactamase-negative ampicillin (AMP)-resistant (BLNAR) strains and three β-lactamase-negative AMP-susceptible (BLNAS) strains, to evaluate the efficacy of AMP, cefcapene (CFPN), levofloxacin (LVX), clarithromycin (CLR), and azithromycin (AZM) in both a cell culture infection model and a mouse infection model. In the cell culture infection model, strains that invade A549 human alveolar epithelial cells were treated with each antibiotic (1 μg/ml). In the mouse infection model, female C57BL/6 mice were intraperitoneally injected with cyclophosphamide (200 mg/kg) three days before intranasal infection with 1 × 10⁹colony-forming units (CFU) of NTHi and on the day of infection. After infection, the mice were orally administered each antibiotic three times daily for three days, except for AZM, which was administered once daily for three days, at a dose of 100 mg/kg/day.</p> <p>Results</p> <p>In the cell culture infection model, it was found that two BLNAR strains were able to enter the cell monolayers by the process of macropinocytosis, and treatment with LVX yielded good bactericidal activity against both strains inside the cells. In the mouse infection model, no bacteria were detected by means of plating the lung homogenates of LVX-treated mice at day 4 after infection, while more than 10⁵CFU of bacteria per tissue sample were detected in nontreated mice.</p> <p>Conclusion</p> <p>Our findings show the outcome and rich benefits of fluoroquinolone treatment of respiratory infections caused by either invasive or noninvasive BLNAR strains of NTHi.</p

A mixed model QTL analysis for sugarcane multiple-harvest-location trial data

Sugarcane-breeding programs take at least 12 years to develop new commercial cultivars. Molecular markers offer a possibility to study the genetic architecture of quantitative traits in sugarcane, and they may be used in marker-assisted selection to speed up artificial selection. Although the performance of sugarcane progenies in breeding programs are commonly evaluated across a range of locations and harvest years, many of the QTL detection methods ignore two- and three-way interactions between QTL, harvest, and location. In this work, a strategy for QTL detection in multi-harvest-location trial data, based on interval mapping and mixed models, is proposed and applied to map QTL effects on a segregating progeny from a biparental cross of pre-commercial Brazilian cultivars, evaluated at two locations and three consecutive harvest years for cane yield (tonnes per hectare), sugar yield (tonnes per hectare), fiber percent, and sucrose content. In the mixed model, we have included appropriate (co)variance structures for modeling heterogeneity and correlation of genetic effects and non-genetic residual effects. Forty-six QTLs were found: 13 QTLs for cane yield, 14 for sugar yield, 11 for fiber percent, and 8 for sucrose content. In addition, QTL by harvest, QTL by location, and QTL by harvest by location interaction effects were significant for all evaluated traits (30 QTLs showed some interaction, and 16 none). Our results contribute to a better understanding of the genetic architecture of complex traits related to biomass production and sucrose content in sugarcane

IL-12p35 induces expansion of IL-10 and IL-35-expressing regulatory B cells and ameliorates autoimmune disease

We thank Dr. Haohua Qian and Yichao Li (Visual function core, NEI, NIH) for technical assistance with OCT; Phyllis Silver (NEI, NIH) for EAU scoring of the eyes; Rashid Mahdi. M.J.M. for technical assistance with western blot analyses and Rafael Villasmil (NEI FLOW Cytometry Core facility) for assistance with FACS analysis.Peer reviewedPublisher PD

Epistasis: Obstacle or Advantage for Mapping Complex Traits?

Identification of genetic loci in complex traits has focused largely on one-dimensional genome scans to search for associations between single markers and the phenotype. There is mounting evidence that locus interactions, or epistasis, are a crucial component of the genetic architecture of biologically relevant traits. However, epistasis is often viewed as a nuisance factor that reduces power for locus detection. Counter to expectations, recent work shows that fitting full models, instead of testing marker main effect and interaction components separately, in exhaustive multi-locus genome scans can have higher power to detect loci when epistasis is present than single-locus scans, and improvement that comes despite a much larger multiple testing alpha-adjustment in such searches. We demonstrate, both theoretically and via simulation, that the expected power to detect loci when fitting full models is often larger when these loci act epistatically than when they act additively. Additionally, we show that the power for single locus detection may be improved in cases of epistasis compared to the additive model. Our exploration of a two step model selection procedure shows that identifying the true model is difficult. However, this difficulty is certainly not exacerbated by the presence of epistasis, on the contrary, in some cases the presence of epistasis can aid in model selection. The impact of allele frequencies on both power and model selection is dramatic

Stakeholders, Green Manufacturing, and Practice Performance: Empirical Evidence from Chinese Fashion Businesses

This study explores the relationship among stakeholders, green manufacturing, and practice performance in the fashion business in China and focuses on assisting companies to enhance environmental awareness and green manufacturing practices. We collect research data by developing questionnaires for various Chinese enterprises. A five-point Likert scale is adopted to enable respondents to indicate the extent to which they agree with the items. Through tests and analyses, the questionnaire is validated as reliable, the structural equation model has a good fitting degree, and hypotheses are proved true. Specifically, corporate stakeholders have a significant positive impact on green manufacturing and practice performance, and green manufacturing has a significant positive impact on practice performance in the context of Chinese fashion businesses. Moreover, corporate stakeholders can have a positive impact on practice performance through green manufacturing. We also propose some policy implications, including implementing compulsive policies and regulations and encouraging and establishing preferential policies, such as tax concessions. Moreover, enterprises should actively strive to improve green manufacturing technology and management level to ensure the smooth implementation of green manufacturing practices. To retain sustained earnings and development, green manufacturing should be the bottom line of involved firms. We also emphasize that the importance of corporate stakeholders should be promoted in consideration of enterprises’ practice performance and future development

Effects of erythropoietin on depressive symptoms and neurocognitive deficits in depression and bipolar disorder

<p>Abstract</p> <p>Background</p> <p>Depression and bipolar disorder are associated with reduced neural plasticity and deficits in memory, attention and executive function. Drug treatments for these affective disorders have insufficient clinical effects in a large group and fail to reverse cognitive deficits. There is thus a need for more effective treatments which aid cognitive function. Erythropoietin (Epo) is involved in neuroplasticity and is a candidate for future treatment of affective disorders. The investigators have demonstrated that a single dose of Epo improves cognitive function and reduces neurocognitive processing of negative emotional information in healthy and depressed individuals similar to effects seen with conventional antidepressants. The current study adds to the previous findings by investigating whether repeated Epo administration has antidepressant effects in patients with treatment resistant depression and reverses cognitive impairments in these patients and in patients with bipolar disorder in remission.</p> <p>Methods/design</p> <p>The trial has a double-blind, placebo-controlled, parallel-group design. 40 patients with treatment-resistant major depression and 40 patients with bipolar disorder in remission are recruited and randomised to receive weekly infusions of Epo (Eprex; 40,000 IU) or saline (NaCl 0.9%) for 8 weeks. Randomisation is stratified for age and gender. The primary outcome parameters for the two studies are: depression severity measured with the Hamilton Depression Rating Scale 17 items (HDRS-17) <abbrgrp><abbr bid="B1">1</abbr></abbrgrp> in study 1 and, in study 2, verbal memory measured with the Rey Auditory Verbal Learning Test (RAVLT) <abbrgrp><abbr bid="B2">2</abbr><abbr bid="B3">3</abbr></abbrgrp>. With inclusion of 40 patients in each study we obtain 86% power to detect clinically relevant differences between intervention and placebo groups on these primary outcomes.</p> <p>Trial registration</p> <p>The trial is approved by the Local Ethics Committee: H-C-2008-092, Danish Medicines Agency: 2612-4020, EudraCT: 2008-04857-14, Danish Data Agency: 2008-41-2711 and ClinicalTrials.gov: NCT 00916552.</p

Cell-Intrinsic NF-κB Activation Is Critical for the Development of Natural Regulatory T Cells in Mice

regulatory T (Treg) cells develop in the thymus and represent a mature T cell subpopulation critically involved in maintaining peripheral tolerance. The differentiation of Treg cells in the thymus requires T cell receptor (TCR)/CD28 stimulation along with cytokine-promoted Foxp3 induction. TCR-mediated nuclear factor kappa B (NF-κB) activation seems to be involved in differentiation of Treg cells because deletion of components of the NF-κB signaling pathway, as well as of NF-κB transcription factors, leads to markedly decreased Treg cell numbers in thymus and periphery. thymic Treg precursors and their further differentiation into mature Treg cells. Treg cell development could neither be completely rescued by the addition of exogenous Interleukin 2 (IL-2) nor by the presence of wild-type derived cells in adoptive transfer experiments. However, peripheral NF-κB activation appears to be required for IL-2 production by conventional T cells, thereby participating in Treg cell homeostasis. Moreover, pharmacological NF-κB inhibition via the IκB kinase β (IKKβ) inhibitor AS602868 led to markedly diminished thymic and peripheral Treg cell frequencies.Our results indicate that Treg cell-intrinsic NF-κB activation is essential for thymic Treg cell differentiation, and further suggest pharmacological NF-κB inhibition as a potential therapeutic approach for manipulating this process