Measurements of four-lepton production at the Z resonance in pp collisions at sqrt[s] = 7 and 8 TeV with ATLAS

Measurements of four-lepton (4ℓ, ℓ=e,μ) production cross sections at the Z resonance in pp collisions at the LHC with the ATLAS detector are presented. For dilepton and four-lepton invariant mass regions m(ℓ+ℓ(-)) > 5 GeV and 80<m(4ℓ) < 100 GeV, the measured cross sections are 76 ± 18(stat) ± 4(syst) ± 1.4(lumi) fb and 107 ± 9(stat) ± 4(syst) ± 3.0(lumi) fb at sqrt[s] = 7 and 8 TeV, respectively. By subtracting the nonresonant 4ℓ production contributions and normalizing with Z → μ(+)μ(-) events, the branching fraction for the Z boson decay to 4ℓ is determined to be (3.20 ± 0.25(stat) ± 0.13(syst)) × 10(-6), consistent with the standard model prediction.

Search for direct top squark pair production in events with a [Formula: see text] boson, [Formula: see text]-jets and missing transverse momentum in [Formula: see text] TeV [Formula: see text] collisions with the ATLAS detector

A search is presented for direct top squark pair production using events with at least two leptons including a same-flavour opposite-sign pair with invariant mass consistent with the [Formula: see text] boson mass, jets tagged as originating from [Formula: see text]-quarks and missing transverse momentum. The analysis is performed with proton-proton collision data at [Formula: see text] collected with the ATLAS detector at the LHC in 2012 corresponding to an integrated luminosity of 20.3 fb[Formula: see text]. No excess beyond the Standard Model expectation is observed. Interpretations of the results are provided in models based on the direct pair production of the heavier top squark state ([Formula: see text]) followed by the decay to the lighter top squark state ([Formula: see text]) via [Formula: see text], and for [Formula: see text] pair production in natural gauge-mediated supersymmetry breaking scenarios where the neutralino ([Formula: see text]) is the next-to-lightest supersymmetric particle and decays producing a [Formula: see text] boson and a gravitino ([Formula: see text]) via the [Formula: see text] process.

The KIT gene is associated with the english spotting coat color locus and congenital megacolon in Checkered Giant rabbits (Oryctolagus cuniculus)

The English spotting coat color locus in rabbits, also known as Dominant white spotting locus, is determined by an incompletely dominant allele (En). Rabbits homozygous for the recessive wild-type allele (en/en) are self-colored, heterozygous En/en rabbits are normally spotted, and homozygous En/En animals are almost completely white. Compared to vital en/en and En/en rabbits, En/En animals are subvital because of a dilated (“mega”) cecum and ascending colon. In this study, we investigated the role of the KIT gene as a candidate for the English spotting locus in Checkered Giant rabbits and characterized the abnormalities affecting enteric neurons and c-kit positive interstitial cells of Cajal (ICC) in the megacolon of En/En rabbits. Twenty-one litters were obtained by crossing three Checkered Giant bucks (En/en) with nine Checkered Giant (En/en) and two en/en does, producing a total of 138 F1 and backcrossed rabbits. Resequencing all coding exons and portions of non-coding regions of the KIT gene in 28 rabbits of different breeds identified 98 polymorphisms. A single nucleotide polymorphism genotyped in all F1 families showed complete cosegregation with the English spotting coat color phenotype (θ = 0.00 LOD  = 75.56). KIT gene expression in cecum and colon specimens of En/En (pathological) rabbits was 5–10% of that of en/en (control) rabbits. En/En rabbits showed reduced and altered c-kit immunolabelled ICC compared to en/en controls. Morphometric data on whole mounts of the ascending colon showed a significant decrease of HuC/D (P<0.05) and substance P (P<0.01) immunoreactive neurons in En/En vs. en/en. Electron microscopy analysis showed neuronal and ICC abnormalities in En/En tissues. The En/En rabbit model shows neuro-ICC changes reminiscent of the human non-aganglionic megacolon. This rabbit model may provide a better understanding of the molecular abnormalities underlying conditions associated with non-aganglionic megacolon.

Highly efficient surface-enhanced Raman scattering substrate formulation by self-assembled gold nanoparticles physisorbed on poly(N-isopropylacrylamide) thermoresponsive hydrogels

Employing thermoresponsive hydrogels as scaffolding material for noble metal surface loading might be useful for the fabrication of surface-enhanced Raman scattering (SERS) surfaces. Here, we report on a new, reproducible, and simple approach to engineer poly(N-isopropylacrylamide) (PNIPAAm) hydrogel surfaces optimized for physisorption of gold nanoparticles (AuNPs). The advantage of this approach consists of the simple mechanism by which AuNPs are adsorbed on hydrogel templates, without sophisticated chemical treatments for their conjugation with the hydrogel. The resulting PNIPAAm-40 nm AuNP modes demonstrate that this approach gives the capability to tune the interparticle distance and, therefore, to control and modulate SERS affinity upon temperature changing.

Maternally inherited genetic variants of CADPS2 are present in autism spectrum disorders and intellectual disability patients

Intellectual disability (ID) and autism spectrum disorders (ASDs) are complex neuropsychiatric conditions, with overlapping clinical boundaries in many patients. We identified a novel intragenic deletion of maternal origin in two siblings with mild ID and epilepsy in the CADPS2 gene, encoding for a synaptic protein involved in neurotrophin release and interaction with dopamine receptor type 2 (D2DR). Mutation screening of 223 additional patients (187 with ASD and 36 with ID) identified a missense change of maternal origin disrupting CADPS2/D2DR interaction. CADPS2 allelic expression was tested in blood and different adult human brain regions, revealing that the gene was monoallelically expressed in blood and amygdala, and the expressed allele was the one of maternal origin. Cadps2 gene expression performed in mice at different developmental stages was biallelic in the postnatal and adult stages; however, a monoallelic (maternal) expression was detected in the embryonal stage, suggesting that CADPS2 is subjected to tissue- and temporal-specific regulation in human and mice. We suggest that CADPS2 variants may contribute to ID/ASD development, possibly through a parent-of-origin effect.

A focus on heme oxygenase-1 (HO-1) inhibitors

The aim of this review is to highlight the advances in the field of heme oxygenase-1 (HO-1) inhibitors over the past years, particularly from a medicinal chemistry point of view; progresses made in the field strongly helped to clarify physiological roles of the heme oxygenase (HO) system. HO is a family of ubiquitously expressed enzymes which regulate the regiospecific catabolism of heme leading to the formation of equimolar amounts of carbon monoxide (CO), ferrous iron (Fe⁺⁺), and biliverdin. HO exists in two distinct, catalytically active isoforms: HO-1 and HO-2. HO-1 is an inducible 32-kDa protein, while HO-2 is a constitutively synthesized 36-kDa protein and generally is unresponsive to any of the inducers of HO-1. A third isoform, HO-3, is still an elusive protein. The HO system, along with its catabolism products, is involved in a variety of crucial physiological functions, including cytoprotection, inflammation, anti-oxidative effects, apoptosis, neuro-modulation, immune-modulation, angiogenesis, and vascular regulation. The use of selective HO inhibitors is a very important tool to clarify the role of the HO system and the mechanisms underlying its physiological effects and pathological involvement; due to the inducible nature of HO-1, selective inhibition of HO-1 isoform is generally preferable. Notably, HO-1 inhibitors may be also beneficial in therapeutic applications and have been mainly studied for treatment of hyperbilirubinemia and certain types of cancer. Historically, the first molecules used as non selective HO-1 inhibitors were metalloporphyrins (Mps). The subsequent development of the imidazole-dioxolane derivatives afforded the first generation of non-porphyrin based, isozyme selective HO-1 inhibitors.

Search for quantum black hole production in high-invariant-mass lepton+jet final states using pp collisions at √s=8 TeV and the ATLAS detector

This Letter presents a search for quantum black-hole production using 20.3 fb-1 of data collected with the ATLAS detector in pp collisions at the LHC at √s = 8 TeV. The quantum black holes are assumed to decay into a final state characterized by a lepton (electron or muon) and a jet. In either channel, no event with a lepton-jet invariant mass of 3.5 TeV or more is observed, consistent with the expected background. Limits are set on the product of cross sections and branching fractions for the lepton+jet final states of quantum black holes produced in a search region for invariant masses above 1 TeV. The combined 95% confidence level upper limit on this product for quantum black holes with threshold mass above 3.5 TeV is 0.18 fb. This limit constrains the threshold quantum black-hole mass to be above 5.3 TeV in the model considered.

A mutation in PAK3 with a dual molecular effect deregulates the RAS/MAPK pathway and drives an X-linked syndromic phenotype

Loss-of-function mutations in PAK3 contribute to non-syndromic X-linked intellectual disability (NS-XLID) by affecting dendritic spine density and morphology. Linkage analysis in a three-generation family with affected males showing ID, agenesis of corpus callosum, cerebellar hypoplasia, microcephaly and ichthyosis, revealed a candidate disease locus in Xq21.33q24 encompassing over 280 genes. Subsequent to sequencing all coding exons of the X chromosome, we identified a single novel variant within the linkage region, affecting a conserved codon of PAK3. Biochemical studies showed that, similar to previous NS-XLID-associated lesions, the predicted amino acid substitution (Lys389Asn) abolished the kinase activity of PAK3. In addition, the introduced residue conferred a dominant-negative function to the protein that drives the syndromic phenotype. Using a combination of in vitro and in vivo studies in zebrafish embryos, we show that PAK3(N389) escapes its physiologic degradation and is able to perturb MAPK signaling via an uncontrolled kinase-independent function, which in turn leads to alterations of cerebral and craniofacial structures in vivo. Our data expand the spectrum of phenotypes associated with PAK3 mutations, characterize a novel mechanism resulting in a dual molecular effect of the same mutation with a complex PAK3 functional deregulation and provide evidence for a direct functional impact of aberrant PAK3 function on MAPK signaling.

Array CGH analysis of a cohort of Russian patients with intellectual disability

The use of array comparative genomic hybridization (array CGH) as a diagnostic tool in molecular genetics has facilitated the identification of many new microdeletion/microduplication syndromes (MMSs). Furthermore, this method has allowed for the identification of copy number variations (CNVs) whose pathogenic role has yet to be uncovered. Here, we report on our application of array CGH for the identification of pathogenic CNVs in 79 Russian children with intellectual disability (ID). Twenty-six pathogenic or likely pathogenic changes in copy number were detected in 22 patients (28%): 8 CNVs corresponded to known MMSs, and 17 were not associated with previously described syndromes. In this report, we describe our findings and comment on genes potentially associated with ID that are located within the CNV regions.

Glenoid and humeral head bone loss in traumatic anterior glenohumeral instability: a systematic review

PURPOSE

The aim of this systematic review is to analyze outcomes of surgical procedures for glenoid and/or humeral bony defects, performed singularly or in combination, in patients with traumatic anterior glenohumeral instability. A secondary aim is to establish in clinical settings which percentage of glenoid or humeral bone loss needs to be treated with a bony procedure to avoid recurrence of dislocation.

METHODS

A systematic review of the literature according to the PRISMA guidelines was performed. A comprehensive search of PubMed, Medline, CINAHL, Cochrane, Embase and Google Scholar databases using various combinations of the keywords "shoulder", "instability", "dislocation", "bone loss", "bony bankart", "osseous glenoid defects", "glenoid bone grafting", "Latarjet", "glenoid", "humeral head", "surgery", "glenohumeral", "Hill Sachs", "Remplissage", over the years 1966-2012 was performed.

RESULTS

Twenty-seven articles, describing patients with glenoid bony defect, humeral bony defect or both in the setting of traumatic anterior glenohumeral instability, were included. A total of 1,816 shoulders in 1,801 patients were included, with a median age at surgery of 27.1 years, ranging from 12 to 75 years. Patients were assessed at a median follow-up period of 2.8 years (ranging from 6 months to 28.2 years). The overall recurrence of redislocation occurred in 117 (6.5 %) shoulders. The redislocation event occurred in 40 of 553 (7.2 %) shoulders with glenoid bony defect, in 30 of 225 (13.3 %) shoulders with humeral bony defect and in 63 of 1,009 (6.3 %) shoulders with both glenoid and humeral involvement.

CONCLUSION

Even though the general principle of recognizing and treating glenoid and humeral bone defects in patients with traumatic anterior glenohumeral instability is widely accepted, few studies are available to date to accurately establish which bone defects should be treated with bone procedures and the exact percentage of bone loss leading to higher risk of redislocation in clinical settings.

Search for dark matter in events with a hadronically decaying W or Z boson and missing transverse momentum in pp collisions at √s=8 TeV with the ATLAS detector

A search is presented for dark matter pair production in association with a W or Z boson in pp collisions representing 20.3  fb(-1) of integrated luminosity at √s=8  TeV using data recorded with the ATLAS detector at the Large Hadron Collider. Events with a hadronic jet with the jet mass consistent with a W or Z boson, and with large missing transverse momentum are analyzed. The data are consistent with the standard model expectations. Limits are set on the mass scale in effective field theories that describe the interaction of dark matter and standard model particles, and on the cross section of Higgs production and decay to invisible particles. In addition, cross section limits on the anomalous production of W or Z bosons with large missing transverse momentum are set in two fiducial regions.

Increased efficiency in geographic ancestry assignment and human identification by combining lineage profiles: The case of the Iranians

OBJECTIVES

This research is a first empirical attempt to quantify the increase of the among-groups variance and the probative value of a DNA evidence when combining profiles based on markers with uniparental inheritance.

METHODS

Yfiler and HVS-I panels of loci were analyzed in 130 healthy unrelated males from six Iranian native groups.

RESULTS

A separate analysis of DNA profiles at the two lineage markers failed to detect a population substructure, whereas maximum levels of genetic diversity (HD = 1) and discrimination capacity (DC = 1) were obtained by combining the two profiles.

CONCLUSIONS

When combined, the forensic efficiency of routinely used panels of lineage markers can be largely sufficient to resolve cases of geographic ancestry and human identification even in genetically homogeneous populations.

Multiplex single particle analysis in microfluidics

A method to combine precise particle alignment in-flow and light scattering profile characterization for micrometric sized particles is reported.

Evidence-based surgical management of spondylolisthesis: reduction or arthrodesis in situ

BACKGROUND

The role of reduction in the operative management of spondylolisthesis is controversial because of its potential complications, including neurologic deficits, prolonged operative time, and loss of reduction. The aim of this systematic review was to compare arthrodesis in situ and arthrodesis after reduction techniques with respect to clinical and radiographic outcomes and safety.

METHODS

We performed a comprehensive search of the PubMed, Ovid MEDLINE, Cochrane, CINAHL, Google Scholar, and Embase databases with use of the keyword "spondylolisthesis" in combination with "surgery," "reduction," "in situ," "low back pain," "high-grade," "lumbar spine," "lumbar instability," and "fusion."

RESULTS

Eight eligible studies, containing reports of 165 procedures involving reduction followed by arthrodesis and 101 procedures involving arthrodesis in situ without reduction, were identified and included. The procedure involving reduction was associated with a significantly greater decrease in the percentage of slippage (p < 0.002) and slip angle (p < 0.003) compared with arthrodesis in situ. Pseudarthrosis was significantly more frequent in the arthrodesis in situ group compared with the reduction group (17.8% compared with 5.5%, p = 0.004). Neurologic deficits were not significantly more prevalent in the reduction group compared with the arthrodesis in situ group (7.8% compared with 8.9%, p = 0.8).

CONCLUSIONS

On the basis on this review, the reduction of high-grade spondylolisthesis potentially improves overall spine biomechanics by correcting the local kyphotic deformity and reducing vertebral slippage. Reduction was not associated with a greater risk of developing neurologic deficits compared with arthrodesis in situ. Both procedures were associated with good clinical outcomes.

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Measurement of jet shapes in top-quark pair events at [Formula: see text] using the ATLAS detector

A measurement of jet shapes in top-quark pair events using 1.8 fb-1 of [Formula: see text]pp collision data recorded by the ATLAS detector at the LHC is presented. Samples of top-quark pair events are selected in both the single-lepton and dilepton final states. The differential and integrated shapes of the jets initiated by bottom-quarks from the top-quark decays are compared with those of the jets originated by light-quarks from the hadronic W-boson decays [Formula: see text] in the single-lepton channel. The light-quark jets are found to have a narrower distribution of the momentum flow inside the jet area than b-quark jets.

Measurement of top quark polarization in top-antitop events from proton-proton collisions at √s=7 TeV using the ATLAS detector

This Letter presents measurements of the polarization of the top quark in top-antitop quark pair events, using 4.7  fb(-1) of proton-proton collision data recorded with the ATLAS detector at the Large Hadron Collider at √s=7  TeV. Final states containing one or two isolated leptons (electrons or muons) and jets are considered. Two measurements of α(ℓ)P, the product of the leptonic spin-analyzing power and the top quark polarization, are performed assuming that the polarization is introduced by either a CP conserving or a maximally CP violating production process. The measurements obtained, α(ℓ)P(CPC)=-0.035±0.014(stat)±0.037(syst) and α(ℓ)P(CPV)=0.020±0.016(stat)(-0.017)(+0.013)(syst), are in good agreement with the standard model prediction of negligible top quark polarization.

Particle alignment in a viscoelastic liquid flowing in a square-shaped microchannel

We demonstrate the possibility to achieve 3D particle focusing in a straight microchannel with a square cross-section by exploiting purely viscoelastic effects. Experiments are carried out by considering an elastic, constant-viscosity aqueous solution of PVP (polyvinylpyrrolidone) as the suspending liquid. Several flow rates and two channel dimensions (with a fixed particle size to channel dimension ratio) are investigated. A novel technique combining particle tracking measurements and numerical simulations is used to reconstruct the position of the flowing particles over the channel cross-section. The results show that, for all the investigated experimental conditions, particles migrate towards the channel centerline. Flow-focusing is enhanced by higher flow rates. The measured particle fractions can be rescaled according to a single dimensionless parameter, as already reported in the literature for the case of cylindrical channels. The so-obtained master curve can be used as a guide to predict the required focusing length. The effect of the entrance on the focusing channel length is also addressed. Finally, analogies and discrepancies with similar previous works are discussed.

The homozygosity index (HI) approach reveals high allele frequency for Wilson disease in the Sardinian population

Wilson disease (WD) is an autosomal recessive disorder resulting in pathological progressive copper accumulation in liver and other tissues. The worldwide prevalence (P) is about 30/million, while in Sardinia it is in the order of 1/10,000. However, all of these estimates are likely to suffer from an underdiagnosis bias. Indeed, a recent molecular neonatal screening in Sardinia reported a WD prevalence of 1:2707. In this study, we used a new approach that makes it possible to estimate the allelic frequency (q) of an autosomal recessive disorder if one knows the proportion between homozygous and compound heterozygous patients (the homozygosity index or HI) and the inbreeding coefficient (F) in a sample of affected individuals. We applied the method to a set of 178 Sardinian individuals (3 of whom born to consanguineous parents), each with a clinical and molecular diagnosis of WD. Taking into account the geographical provenance of the parents of every patient within Sardinia (to make F computation more precise), we obtained a q=0.0191 (F=7.8 × 10(-4), HI=0.476) and a corresponding prevalence P=1:2732. This result confirms that the prevalence of WD is largely underestimated in Sardinia. On the other hand, the general reliability and applicability of the HI approach to other autosomal recessive disorders is confirmed, especially if one is interested in the genetic epidemiology of populations with high frequency of consanguineous marriages.