Measurement of the [Formula: see text] meson lifetime using [Formula: see text] decays

The lifetime of the [Formula: see text] meson is measured using semileptonic decays having a [Formula: see text] meson and a muon in the final state. The data, corresponding to an integrated luminosity of [Formula: see text], are collected by the LHCb detector in [Formula: see text] collisions at a centre-of-mass energy of 8 TeV. The measured lifetime is [Formula: see text]where the first uncertainty is statistical and the second is systematic.

Efficacy of biologic agents in improving the Health Assessment Questionnaire (HAQ) score in established and early rheumatoid arthritis: a meta-analysis with indirect comparisons

OBJECTIVES

The Health Assessment Questionnaire (HAQ) is a validated physical function measure. It is predictive for disability and mortality. The objective of this study was to determine the comparative efficacy of biologic agents in improving HAQ in patients with established RA who failed DMARDs or anti- TNF agents and in early RA (ERA).

METHODS

We performed random effects meta-analyses of published randomised, placebo-controlled trials. Outcome was the mean difference in change in HAQ for biologic agents compared to controls (ΔHAQB-ΔHAQC). Indirect comparisons of the different biologic drugs were conducted using the Q-test based on analysis of variance. Meta-regression was performed using the method of moments.

RESULTS

Twenty-eight trials were included: 19 with DMARD-failures; 4 with anti-TNF-failures and 5 ERA. The following biologics were represented: abatacept, adalimumab, certolizumab, etanercept, golimumab, infliximab, rituximab and tocilizumab. Efficacy of biologics at reducing HAQ was significantly different based on prior treatment (p=0.001). In RA patients with DMARD failures, ΔHAQB-ΔHAQC was -0.22; 95%CI: -0.24, -0.20 (I2=55%). Infliximab, abatacept and tocilizumab had lower ΔHAQB-ΔHAQC compared to other biologics (p<0.02). In anti-TNF-failures, ΔHAQB-ΔHAQC was -0.36; 95%CI: -0.42, -0.30 (I2=0%). In ERA, methotrexate-naïve trials, ΔHAQB-ΔHAQC was -0.19; 95% CI: -0.26, -0.13 (I2=0%). There were no significant differences in the efficacy of different biologics for anti-TNF failures and ERA.

CONCLUSIONS

Biologic agents were efficacious at lowering HAQ in RA. Differences between agents in RA with DMARD failures were less than the minimally clinically important difference for HAQ; therefore, the clinical significance of these differences is unclear.

Observation of photon polarization in the b→sγ transition

This Letter presents a study of the flavor-changing neutral current radiative B±→K±π∓π±γ decays performed using data collected in proton-proton collisions with the LHCb detector at 7 and 8 TeV center-of-mass energies. In this sample, corresponding to an integrated luminosity of 3  fb-1, nearly 14 000 signal events are reconstructed and selected, containing all possible intermediate resonances with a K±π∓π± final state in the [1.1,1.9]  GeV/c2 mass range. The distribution of the angle of the photon direction with respect to the plane defined by the final-state hadrons in their rest frame is studied in intervals of K±π∓π± mass and the asymmetry between the number of signal events found on each side of the plane is obtained. The first direct observation of the photon polarization in the b→sγ transition is reported with a significance of 5.2σ.

Search for Majorana neutrinos in B- → π+ μ- μ- decays

A search for heavy Majorana neutrinos produced in the B- → π+ μ- μ- decay mode is performed using 3  fb(-1) of integrated luminosity collected with the LHCb detector in pp collisions at center-of-mass energies of 7 and 8 TeV at the LHC. Neutrinos with masses in the range 250 to 5000 MeV and lifetimes from zero to 1000 ps are probed. In the absence of a signal, upper limits are set on the branching fraction B(B- → π+ μ- μ-) as functions of neutrino mass and lifetime. These limits are on the order of 10(-9) for short neutrino lifetimes of 1 ps or less. Limits are also set on the coupling between the muon and a possible fourth-generation neutrino.

Detection of submicroscopic chromosomal aberrations by array-based comparative genomic hybridization in fetuses with congenital heart disease

OBJECTIVES

To evaluate the usefulness of array-based comparative genomic hybridization (aCGH) for prenatal genetic diagnosis of congenital heart disease (CHD), with and without associated anomalies, and to explore the relationship between submicroscopic chromosomal aberrations and CHD.

METHODS

In this prospective study we investigated 76 consecutive singleton fetuses with abnormal cardiac ultrasound findings, normal karyotype and negative or no fluorescence in-situ hybridization results for 22q11.2 deletion syndrome. All pregnancies underwent aCGH in a comprehensive search for chromosomal aberrations. The relationship between copy number variations (CNVs) and CHD was determined by comparing clinical findings to chromosomal databases.

RESULTS

CNVs that were benign or had no clinical significance were detected in 18/76 (23.7%) cases. CNVs of unknown clinical significance (i.e. VOUS) were detected in 4/76 (5.3%) cases. Pathogenic CNVs were detected in 5/76 (6.6%) cases. Fetuses with CHD and additional structural abnormalities demonstrated no difference in number of pathogenic CNVs when compared with fetuses with isolated CHD (7.4% (n = 2/27) vs 6.1% (n = 3/49), P > 0.05).

CONCLUSION

In this study cohort, aCGH analysis significantly improved the detection of submicroscopic chromosomal aberrations in pregnancies with CHD, as compared with conventional cytogenetics. Our results suggest that aCGH can provide additional genetic information in fetuses with abnormal heart findings.

Measurement of the Bs(0) → Ds-Ds+ and Bs(0) → D-Ds+ effective lifetimes

The first measurement of the effective lifetime of the B(s)(0) meson in the decay B(s)(0) → Ds-Ds+ is reported using a proton-proton collision data set, corresponding to an integrated luminosity of 3 fb(-1), collected by the LHCb experiment. The measured value of the B(s)(0) → Ds-Ds+ effective lifetime is 1.379 ± 0.026 ± 0.017 ps, where the uncertainties are statistical and systematic, respectively. This lifetime translates into a measurement of the decay width of the light B(s)(0) mass eigenstate of ΓL = 0.725 ± 0.014 ± 0.009 ps(-1). The B(s)(0) lifetime is also measured using the flavor-specific B(s)(0)→ D-Ds+ decay to be 1.52 ± 0.15 ± 0.01 ps.

Observation of B(s)(0) → J/ψ f1(1285) decays and measurement of the f1(1285) mixing angle

Decays of B(s)(0) and B(0) mesons into J/ψ π+π-π+π- final states, produced in pp collisions at the LHC, are investigated using data corresponding to an integrated luminosity of 3 fb-1 collected with the LHCb detector. B(s)(0) → J/ψ f1(1285) decays are seen for the first time, and the branching fractions are measured. Using these rates, the f1(1285) mixing angle between strange and nonstrange components of its wave function in the qq structure model is determined to be ±(24.0-2.6-0.8+3.1+0.6)°. Implications on the possible tetraquark nature of the f1(1285) are discussed.

Excellent antimicrobial properties of silver-loaded mesoporous silica SBA-15

AIMS

To synthesize silver-loaded mesoporous silica SBA-15 (Ag/SBA-15) materials and examine their antimicrobial action and antimicrobial mechanism.

METHODS AND RESULTS

Ag/SBA-15 materials were prepared by means of incipient wetness impregnation, impregnation and direct hydrothermal synthesis methods. The antimicrobial activity of Ag/SBA-15 was investigated using Escherichia coli as an indicator bacterium, and the antimicrobial mechanism was explored. The properties and Ag(+) release behaviour of Ag/SBA-15 materials were compared. Experimental results showed that Ag/SBA-15 materials resulted in 7·5 log inactivation of E. coli for only 60 min, which exhibited very high antimicrobial activities at room temperature without using any light or electrical power input. The cell wall and cell membrane were destroyed in the antimicrobial process, leading to leakage of intracellular components. The formation of extracellular reactive oxygen species (ROS) involved in the bactericidal process was confirmed. Production of intracellular ROS was also discovered.

CONCLUSIONS

Ag/SBA-15 exhibited high antimicrobial activity against E. coli. This antimicrobial effect was a synergistic action between extracellular ROS and the toxicity of Ag(+) , which induced intracellular ROS production and subsequent cell death.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study revealed for the first time the antimicrobial activities and mechanisms of Ag/SBA-15 materials prepared with different methods.

MEN1 tumorigenesis in the pituitary and pancreatic islet requires Cdk4 but not Cdk2

Recent studies suggest that physiological and tumorigenic proliferation of mammalian cells is controlled by multiple cyclin-dependent kinases (CDKs) largely in tissue-specific manners. We and others previously demonstrated that adult mice deficient for the D-cyclin-dependent kinase CDK4 (Cdk4^−/− mice) exhibit hypoplasia in the pituitary and pancreatic islet due to primary postnatal defects in proliferation. Intriguingly, those neuroendocrine tissues affected in Cdk4^−/− mice are the primary targets of tumorigenesis in the syndrome of multiple endocrine neoplasia type-1 (MEN1). Mice with heterozygous disruption of the tumor suppressor Men1 gene (Men1^+/−) develop tumors in the pituitary, pancreatic islets and other neuroendocrine tissues, which is analogous to humans with MEN1 mutations. To explore the genetic interactions between loss of Men1 and activation of CDKs, we examined the impact of Cdk4 or Cdk2 disruption on tumorigenesis in Men1^+/− mice. A majority of Men1^+/− mice with wild-type CDKs developed pituitary and islet tumors by 15 months of age. Strikingly, Men1^+/−; Cdk4^−/− mice did not develop any tumors, and their islets and pituitaries remained hypoplastic with decreased proliferation. In contrast, Men1^+/−; Cdk2^−/− mice showed pituitary and islet tumorigenesis comparable to those in Men1^+/− mice. Pituitaries of Men1^+/−; Cdk4^−/− mice showed no signs of loss of heterozygosity (LOH) in the Men1 locus, while tumors in Men1^+/− mice and Men1^+/−; Cdk2^−/− mice exhibited LOH. Consistently, CDK4 knockdown in INS-1 insulinoma cells inhibited glucose-stimulated cell cycle progression with a significant decrease in phosphorylation of retinoblastoma protein (RB) at specific sites including Ser780. CDK2 knockdown had minimum effects on RB phosphorylation and cell cycle progression. These data suggest that CDK4 is a critical downstream target of MEN1-dependent tumor suppression and is required for tumorigenic proliferation in the pituitary and pancreatic islet, whereas CDK2 is dispensable for tumorigenesis in these neuroendocrine cell types.

Magnetic resonance imaging of fixed post mortem brains reliably reflects subcortical vascular pathology of frontal, parietal and occipital white matter

AIMS

Subcortical vascular pathology of the white and deep grey matter (WM and DGM) is associated with cognitive impairment. Routine neuropathological assessment of subcortical vascular pathology is based on semiquantitative scoring of characteristic lesions in a limited number of histological slides from selected WM and DGM areas. Clinically, WM and DGM lesions are visualized as hyper-intensities on magnetic resonance imaging (MRI). The aim of this study was to evaluate the feasibility of MRI on fixed post mortem brain hemispheres to complement routine neuropathological assessment of subcortical vascular pathology.

METHODS

We assessed subcortical vascular pathology in 40 post mortem brain hemispheres from demented (n = 26) and nondemented (n = 14) individuals (mean age 83.2 ± 14.8 years; 62.5% female) using (i) routine histological assessment; (ii) extensive histological assessment of the entire hemisphere at 7-mm intervals; and (iii) full T2-weighted MRI performed on fixed post mortem brain hemispheres.

RESULTS

In both WM and DGM routine histological scores for subcortical vascular pathology were significantly lower (P < 0.01) than the corresponding scores obtained by extensive histological assessment. In contrast, no significant differences were seen between scores obtained by MRI and extensive histological assessment in frontal, parietal and occipital lobes while MRI scores were significantly lower in the temporal WM and DGM (P < 0.01).

CONCLUSIONS

The results of our study indicate that routine histological assessment underrates subcortical vascular pathology and we conclude that MRI could be used in addition to complement neuropathological post mortem assessment of subcortical vascular pathology of the WM.

Progress of superconducting electron cyclotron resonance ion sources at Institute of Modern Physics (IMP)

Superconducting ECR ion sources can produce intense highly charged ion beams for the application in heavy ion accelerators. Superconducting Electron Resonance ion source with Advanced Design (SECRAL) is one of the few fully superconducting ECR ion sources that has been successfully built and put into routine operation for years. With enormous efforts and R&D work, promising results have been achieved with the ion source. Heated by the microwave power from a 7 kW/24 GHz gyrotron microwave generator, very intense highly charged gaseous ion beams have been produced, such as 455 eμA Xe(27+), 236 eμA Xe(30+), and 64 eμA Xe(35+). Since heavy metallic ion beams are being more and more attractive and important for many accelerator projects globally, intensive studies have been made to produce highly charged heavy metal ion beams, such as those from bismuth and uranium. Recently, 420 eμA Bi(30+) and 202 eμA U(33+) have been produced with SECRAL source. This paper will present the latest results with SECRAL, and the operation status will be discussed as well. An introduction of recently started SECRAL II project will also be given in the presentation.

The oxytocin-bone axis

We recently demonstrated a direct action of oxytocin (OT) on skeletal homeostasis, mainly mediated through stimulation of osteoblasts (OBs) formation and through the reciprocal modulation of osteoclast (OCs) formation and function. Thus, mice lacking the hormone or its receptor develop a low turnover osteoporosis that worsens with age in both sexes. The skeletons of OT (Ot) and OT receptor (Oxtr) null mice display a pronounced decrease in vertebral and femoral trabecular volume. At the cellular level, OBs from Ot KO and Oxtr KO mice exhibit lower mineralization activity and, at the mRNA level, all master genes for osteoblast differentiation are down-regulated. Moreover, OT has dual effects on OCs: it increases osteoclast formation both directly, by activating nuclear factor kB (NFkB) and mitogen-activated protein kinase (MAPK) signalling and, indirectly, through the up-regulation of receptor activator nuclear factor-kappaB ligand synthesis by OBs. On the other hand, it inhibits bone resorption by triggering cytosolic Ca(2+) release and nitric oxide synthesis in mature OCs. OT is locally produced by osteoblasts acting as paracrine-autocrine regulators of bone formation modulated by oestrogens. The oestrogen signal involved in this feedforward circuit is nongenomic because it requires an intact MAPK kinase signal transduction pathway, instead of the classical nuclear translocation of oestrogen receptor. The ability of oestrogen to increase bone mass in vivo is to some extent OXTR-dependent. Thus, Oxtr KO mice injected 17β-oestradiol did not show any effects on bone formation parameters, whereas the same treatment increases trabecular and cortical bone in wild-type mice. An intact OT autocrine-paracrine circuit appears to be essential for optimal skeletal remodelling.

Measurements of indirect CP asymmetries in D0 → K- K+ and D0 → π- π+ decays

A study of indirect CP violation in D0 mesons through the determination of the parameter AΓ is presented using a data sample of pp collisions, corresponding to an integrated luminosity of 1.0  fb(-1), collected with the LHCb detector and recorded at the center-of-mass energy of 7 TeV at the LHC. The parameter AΓ is the asymmetry of the effective lifetimes measured in decays of D0 and D0 mesons to the CP eigenstates K- K+ and π- π+. Fits to the data sample yield AΓ(KK)=(-0.35±0.62±0.12)×10(-3) and AΓ(ππ)=(0.33±1.06±0.14)×10(-3), where the first uncertainties are statistical and the second systematic. The results represent the world's best measurements of these quantities. They show no difference in AΓ between the two final states and no indication of CP violation.

MicroRNA-193a-3p and -5p suppress the metastasis of human non-small-cell lung cancer by downregulating the ERBB4/PIK3R3/mTOR/S6K2 signaling pathway

The metastatic cascade is a complex and multistep process with many potential barriers. Recent evidence has shown that microRNAs (miRNAs) are involved in carcinogenesis and tumor progression in non-small-cell lung cancer (NSCLC). In this study, by comparing the miRNA expression profiles of SPC-A-1sci (high metastatic) and SPC-A-1 (weakly metastatic) cells, we demonstrated that the downregulation and function of miR-193a-3p and miR-193a-5p in NSCLC metastasis and the expression of these miRNAs was suppressed in NSCLC compared with corresponding non-tumorous tissues. Decreased miR-193a-3p/5p expression was significantly associated with tumor node metastasis (TNM) and lymph node metastasis. Furthermore, functional assays showed that the overexpression of miR-193a-3p/5p inhibited NSCLC cell migration, invasion and epithelial-mesenchymal transition (EMT) in vitro and lung metastasis formation in vivo. In addition, we discovered that ERBB4 and S6K2 were the direct targets of miR-193a-3p and that PIK3R3 and mTOR were the direct targets of miR-193a-5p in NSCLC. We also observed that miR-193a-3p/5p could inactivate the AKT/mTOR signaling pathway. Thus, miR-193a-3p/5p functions as a tumor suppressor and has an important role in NSCLC metastasis through ERBB signaling pathway.

Hand, foot and mouth disease in Guangdong, China, in 2013: new trends in the continuing epidemic

Millions of incidents of hand, foot and mouth disease occur annually in China, with EVA71 and CVA16 as two major causative pathogens. A provincial surveillance system has been implemented in Guangdong for almost 5 years to analyze the aetiological spectrum and epidemic changes. An unusual enterovirus type, CVA6, was identified as the predominant serotype associated with an HFMD epidemic from late 2012 to 2013. In contrast to virus strains isolated before, all CVA6/CHN/2012-2013 strains segregated into one major genetic cluster. This study suggested that one cluster of circulating CVA6 strain had emerged as a new and major cause during a continuing HFMD epidemic in Guangdong, China.

Measurement of CP violation in the phase space of B± → K+ K- π± and B± → π+ π- π± decays

The charmless decays B± → K+ K- π± and B± → π+ π- π± are reconstructed in a data set of pp collisions with an integrated luminosity of 1.0  fb(-1) and center-of-mass energy of 7 TeV, collected by LHCb in 2011. The inclusive charge asymmetries of these modes are measured to be A(CP)(B± → K+ K- π±) = -0.141±0.040  (stat)±0.018 (syst)±0.007(J/ψ K±) and A(CP)(B± → π+ π- π±) = 0.117±0.021 (stat)±0.009 (syst)±0.007(J/ψ K±), where the third uncertainty is due to the CP asymmetry of the B± → J/ψK± reference mode. In addition to the inclusive CP asymmetries, larger asymmetries are observed in localized regions of phase space.

Mitral annular tissue velocity in the diagnosis of coronary artery disease

OBJECTIVE

Non-invasive methods of coronary disease detection are immediately needed. Recent work suggested that mitral annular tissue velocity measurements could be helpful for assessing left ventricular function. We aim to determine the effect of coronary artery lesion on left ventricular function using tissue Doppler imaging (TDI), and to discuss the role of mitral annular tissue velocity in the diagnosis of coronary heart disease (CHD).

PATIENTS AND METHODS

Coronary angiographic examinations were conducted for 68 patients with suspected CHD. Left ventricular ejection fraction (LVEF), early diastolic mitral flow velocity E, late diastolic mitral flow velocity A, mean systolic (Sa) and mean early diastolic velocity (Ea) of the septal and lateral mitral annulus were measured before the angiographic examination. Patients were grouped according to the number of branches with ≥ 50% stenosis. The control group has 15 individuals. The remaining 53 patients with stenosis in 1, 2 and 3 branches were grouped into 1-Branch, 2-Branch, 3-Branch-Light-Condition and 3-Branch-Heavy-Condition groups, respectively. No significant differences in the other general health parameters of the patients were found.

RESULTS

There was no significant difference in LVEF and E/A but in Sa, Ea and E/Ea values between CHD and non-CHD patients. The E/Ea value was significantly elevated in CHD patients, aggravated by this pathological condition. The area bounded by the ROC (receiver operating characteristic) curve of E/Ea is the largest. The sensitivity and specificity of using E/Ea > 8.34 as the diagnostic criterion to pinpoint CHD were 77.4% and 100%, respectively.

CONCLUSIONS

E/Ea is a good indicator of diastolic function and can be useful to diagnose CHD.

Identifying significant crosstalk of pathways in tuberous sclerosis complex

OBJECTIVE

Tuberous sclerosis complex (TSC) is the second most common phakomatosis and is characterized by the formation of benign hamartomas and low-grade neoplasms in multiple organ systems. In this study, our objective here was to explore the interaction and crosstalk between pathways in response to tuberous sclerosis complex.

MATERIALS AND METHODS

We enriched the significant pathways and made the crosstalk analysis of the significant pathways.

RESULTS

The results showed that ECM-receptor interaction was a significant pathway in TSC. In addition, insulin-signaling and mTOR signaling also have been identified involved in TSC here, which have been well characterized. Further analysis indicated that there was a crosstalk between ECM-receptor interaction and antigen processing and presentation, ECM-receptor interaction and apoptosis, and leishmaniasis-oxidative phosphorylation-pancreatic cancer. In this study, a network-based approach was used to analyze the crosstalk among TSC related pathways. The crosstalk of pathways is found and analyzed using the PPI datasets and expression profiles.

CONCLUSIONS

Our work showed that comprehensive and system-wide analysis could provide evidence for TSC pathway and complement the traditional component-based approaches. The crosstalk identified might provide new alternative insights into the TSC pathology, which may contribute to the development of novel therapeutic targets for TSC.

Measurement of D0-D0 mixing parameters and search for CP violation using D0 → K+ π- decays

Measurements of charm mixing parameters from the decay-time-dependent ratio of D0 → K+ π- to D0 → K- π+ rates and the charge-conjugate ratio are reported. The analysis uses data, corresponding to 3  fb(-1) of integrated luminosity, from proton-proton collisions at 7 and 8 TeV center-of-mass energies recorded by the LHCb experiment. In the limit of charge-parity (CP ) symmetry, the mixing parameters are determined to be x'2=(5.5±4.9)×10(-5), y'=(4.8±1.0)×10(-3), and RD=(3.568±0.066)×10(-3). Allowing for CP violation, the measurement is performed separately for D0 and D0 mesons yielding AD=(-0.7±1.9)%, for the direct CP-violating asymmetry, and 0.75<|q/p|<1.24 at the 68.3% confidence level, for the parameter describing CP violation in mixing. This is the most precise determination of these parameters from a single experiment and shows no evidence for CP violation.