Chromatin restoration following nucleotide excision repair involves the incorporation of ubiquitinated H2A at damaged genomic sites

Restoration of functionally intact chromatin structure following DNA damage processing is crucial for maintaining genetic and epigenetic information in human cells. Here, we show the UV-induced uH2A foci formation in cells lacking XPC, DDB2, CSA or CSB, but not in cells lacking XPA, XPG or XPF indicating that uH2A incorporation relied on successful damage repair occurring through either GGR or TCR sub-pathway. In contrast, XPA, XPG or XPF were not required for formation of γH2AX foci in asynchronous cells. Notably, the H2A ubiquitin ligase Ring1B, a component of Polycomb repressor complex 1, did not localize at DNA damage sites. However, histone chaperone CAF-1 showed distinct localization to the damage sites. Knockdown of CAF-1 p60 abolished CAF-1 as well as uH2A foci formation. CAF-1 p150 was found to associate with NER factors TFIIH, RPA p70 and PCNA in chromatin. These data demonstrate that successful NER of genomic lesions and prompt CAF-1-mediated chromatin restoration link uH2A incorporation at the sites of damage repair within chromatin.     

Yeheb (<Emphasis Type="Italic">Cordeauxia</Emphasis><Emphasis Type="Italic">edulis</Emphasis>) extract deters feeding and oviposition of <Emphasis Type="Italic">Plutella xylostella</Emphasis> and attracts its natural enemy

The effects of yeheb (Cordeauxia edulis Hemsl.) leaf extract on feeding and oviposition by diamondback moth (DBM) (Plutella xylostella L.) and the behavior of DBM parasitoid, Cotesia vestalis (Haliday), were studied. Volatile organic compounds (VOCs) from the headspace of intact and DBM-damaged broccoli plants sprayed with yeheb extracts (YE) were also analyzed. Larval feeding and growth, and oviposition by adult DBM were strongly inhibited by the extract. Cotesia vestalis were attracted to volatile blends from intact or DBM-damaged broccoli plants sprayed with YE over intact plants sprayed with water or methanol. Analyses of VOCs in the headspace of broccoli plants revealed that both intact and DBM-damaged plants sprayed with YE showed remarkable differences in sesquiterpene compounds compared to intact control treatments. These combined negative effects of YE on DBM fitness together with positive effects on the parasitoid show that yeheb is a potential source of compounds for use in integrated pest management to control damage caused by DBM.     

The influence of pre-operative risk on the number of circulating endothelial progenitor cells during cardiopulmonary bypass

Background aimsThe number of circulating endothelial progenitor cells (EPC) depends on cytokine release and is also associated with cardiovascular risk factors. During cardiopulmonary bypass (CPB) the endothelium is the first organ to be affected by mechanical and immunologic stimuli. We hypothesized that the magnitude of EPC mobilization by CPB correlates with the pre-operative cardiovascular morbidity profile.MethodsEPC were quantified in blood samples from 30 patients who underwent cardiac surgery by magnetic bead isolation and fluorescence-activated cell sorting (FACS) analysis, based on concomitant expression of CD34, CD133 and CD309. Patients were divided into two groups based on the European System for Cardiac Operative Risk Evaluation (EuroSCORE): low risk (LR) and high risk (HR). Ten healthy volunteers served as controls. Samples were obtained before the start of CPB and at 1 and 24 h post-operatively. Plasma samples were collected for determination of release levels of cytokines and growth factors.ResultsAll CPB patients showed a significantly reduced basal number of EPC compared with healthy individuals (LR 5.60 ± 0.39/mL, HR 3.89 ± 0.34/ mL, versus control 0.807 ± 0.82/mL, P = 0.012 versus LR, P < 0.001 versus HR). CPB induced EPC release that peaked 1 h after surgery (pre-operative 4.79 ± 0.32/mL, 1 h 57.49 ± 5.31/mL, 24 h 6.67 ± 1.05/mL, P < 0.001 pre-operative versus 1 h, P < 0.001 pre-operative versus 24 h) and was associated with the duration of CPB. However, EPC release was significantly attenuated in HR patients (33.09 ± 3.58/mL versus 81.89 ± 4.36/mL at 1 h after CPB, P < 0.0001) and inversely correlated with the pre-operative EuroSCORE. Serum granulocyte–colony-stimulating factor (G-CSF), stem cell factor (SCF) and vascular endothelial growth factor (VEGF) levels increased throughout the observation period and were also correlated with the EPC count.ConclusionsCardiovascular risk factors influence the mobilization of EPC from the bone marrow after stimulation by CPB. This could be secondary to impaired mobilization or the result of increased EPC turnover, and may have implications for future cell therapy strategies in cardiac surgical patients.     

Nlrp3: An immune sensor of cellular stress and infection

Innate immune cells rely on pathogen recognition receptors such as the nucleotide-binding and oligomerization domain (NOD)-like receptor (NLR) family to mount an appropriate immune response against microbial threats. The NLR protein Nlrp3 senses microbial ligands, endogenous danger signals and crystalline substances in the cytosol to trigger the assembly of a large caspase-1-activating protein complex termed the Nlrp3 inflammasome. Autoproteolytic maturation of caspase-1 zymogens in the Nlrp3 inflammasome leads to maturation and extracellular release of the pro-inflammatory cytokines interleukin (IL)-1β and IL-18. Gain-of-function mutations in the NOD domain of Nlrp3 are associated with auto-inflammatory disorders characterized by skin rashes and prolonged episodes of fever. In addition, decreased Nlrp3 expression was recently linked with susceptibility to Crohn's disease in humans. In this review, we discuss recent developments on the role of the Nlrp3 inflammasome in innate immunity, its activation mechanisms and the auto-inflammatory disorders associated with deregulation of Nlrp3 inflammasome activity.     

WAMI: a web server for the analysis of minisatellite maps

Background  

Minisatellites are genomic loci composed of tandem arrays of short repetitive DNA segments. A minisatellite map is a sequence of symbols that represents the tandem repeat array such that the set of symbols is in one-to-one correspondence with the set of distinct repeats. Due to variations in repeat type and organization as well as copy number, the minisatellite maps have been widely used in forensic and population studies. In either domain, researchers need to compare the set of maps to each other, to build phylogenetic trees, to spot structural variations, and to study duplication dynamics. Efficient algorithms for these tasks are required to carry them out reliably and in reasonable time.     

Synthesis and evaluation of phenoxy acetic acid derivatives as [corrected] anti-mycobacterial agents

In present investigation, 2-(4-formyl-2-methoxyphenoxy) acetic acid on condensation with various ketones in methanolic KOH solution yielded the corresponding chalcones (1-3). These corresponding chalcones were reacted with appropriate acid hydrazide in glacial acetic acid led to the formation of phenoxy acetic acid derivatives. All newly synthesized compounds were evaluated for their anti-mycobacterial activities against Mycobacterium tuberculosis H(37)Rv.     

Synthesis and antibacterial activity of novel oxazolidinones bearing N-hydroxyacetamidine substituent

Novel oxazolidinone antibacterials containing N-hydroxyacetamidine moiety are synthesized with the diversity at C-5 terminus. These compounds have been evaluated against a panel of clinically relevant gram-positive and gram-negative pathogens. Most of the analogs in this series displayed activity superior to Linezolid and in vivo efficacies of selected oxazolidinones are also disclosed herein.     

A chloroplast genealogy of myrmecophytic Macaranga species (Euphorbiaceae) in Southeast Asia reveals hybridization, vicariance and long-distance dispersals

Macaranga (Euphorbiaceae) includes about 280 species with a palaeotropic distribution. The genus not only comprises some of the most prominent pioneer tree species in Southeast Asian lowland dipterocarp forests, it also exhibits a substantial radiation of ant-plants (myrmecophytes). Obligate ant-plant mutualisms are formed by about 30 Macaranga species and 13 ant species of the genera Crematogaster or Camponotus. To improve our understanding of the co-evolution of the ants and their host plants, we aim at reconstructing comparative organellar phylogeographies of both partners across their distributional range. Preliminary evidence indicated that chloroplast DNA introgression among closely related Macaranga species might occur. We therefore constructed a comprehensive chloroplast genealogy based on DNA sequence data from the noncoding ccmp2, ccmp6, and atpB-rbcL regions for 144 individuals from 41 Macaranga species, covering all major evolutionary lineages within the three sections that contain myrmecophytes. A total of 88 chloroplast haplotypes were identified, and grouped into a statistical parsimony network that clearly distinguished sections and well-defined subsectional groups. Within these groups, the arrangement of haplotypes followed geographical rather than taxonomical criteria. Thus, up to six chloroplast haplotypes were found within single species, and up to seven species shared a single haplotype. The spatial distribution of the chloroplast types revealed several dispersals between the Malay Peninsula and Borneo, and a deep split between Sabah and the remainder of Borneo. Our large-scale chloroplast genealogy highlights the complex history of migration, hybridization, and speciation in the myrmecophytes of the genus Macaranga. It will serve as a guideline for adequate sampling and data interpretation in phylogeographic studies of individual Macaranga species and species groups.     

Ligand design and synthesis of new imidazo[5,1-b]quinazoline derivatives as alpha1-adrenoceptor agonists and antagonists

A series of new imidazo[5,1-b]quinazoline derivatives (VII-IX) was designed, synthesized, and biologically evaluated for their in vivo hypotensive or hypertensive activities. The design of these compounds was based upon the molecular modeling simulation of the fitting values and conformational energy values of the best-fitted conformers to both the alpha(1)-adrenoceptor (alpha(1)-AR) agonist and alpha(1)-adrenoceptor (alpha(1)-AR) antagonist hypotheses. These hypotheses were generated from their corresponding lead compounds using CATALYST software. The simulation studies predicted that compounds IXa and IXe would have probable affinity for the alpha(1)-AR antagonist hypothesis, while compounds IXb, IXc, and IXg predicted a higher affinity for the alpha(1)-AR agonist hypothesis. In vivo biological evaluation of these compounds for their effects on the blood pressure of normotensive cats was consistent with the results of molecular modeling studies, where compounds IXa and IXe exhibited hypotensive activity, while compounds IXb, IXc, and IXg resulted in increasing the blood pressure of the experimental animals at different doses.     

Rectal immunization with rotavirus virus-like particles induces systemic and mucosal humoral immune responses and protects mice against rotavirus infection

To evaluate whether the rectal route of immunization may be used to provide appropriate protection against enteric pathogens such as rotaviruses (RV), we studied the antibody response and the protection induced by rectal immunization of mice with RV virus-like particles (VLP). For this purpose, 6-week-old BALBc mice were rectally immunized twice with RV 8-2/6/7-VLP derived from the bovine RV RF81 strain either alone or combined with various adjuvants including four toxins [cholera toxin (CT) and three attenuated Escherichia coli-derived heat-labile toxins (LTs), LT(R192G), LT(R72), and LT(K63)] and two Toll-like receptor-targeting adjuvants (CpG and resiquimod). Six weeks after the second immunization, mice were challenged with murine RV strain ECw. RV VLP administered alone were not immunogenic and did not protect mice against RV challenge. By contrast, RV VLP combined with any of the toxin adjuvants were immunogenic (mice developed significant titers of anti-RV immunoglobulin A [IgA] in both serum and feces and of anti-RV IgG in serum) and either efficiently induced complete protection of the mice (no detectable fecal virus shedding) or, for LT(K63), reduced the amount of fecal virus shedding after RV challenge. When combined with RV VLP, CpG and resiquimod failed to achieve protection, although CpG efficiently induced an antibody response to RV. These results support the consideration of the rectal route for the development of new immunization strategies against RV infection. Rectal delivery of a VLP-based vaccine might allow the use of adjuvants less toxic than, but as efficient as, CT.