Search for new dielectron resonances and Randall-Sundrum gravitons at the collider detector at Fermilab

A search for new dielectron-mass resonances using data recorded by the CDF II detector and corresponding to an integrated luminosity of 5.7  fb(-1) is presented. No significant excess over the expected standard model prediction is observed. In this data set, an event with the highest dielectron mass ever observed (960  GeV/c(2)) was recorded. The results are interpreted in the Randall-Sundrum (RS) model. Combined with the 5.4  fb(-1) diphoton analysis, the RS-graviton lower-mass limit for the coupling k/M¯(Pl)=0.1 is 1058  GeV/c(2), making it the strongest limit to date.

Limits on anomalous trilinear gauge couplings in Zγ events from pp¯ collisions at √s=1.96 TeV

Using Zγ candidate events collected by the CDF detector at the Tevatron Collider, we search for potential anomalous (non-standard-model) couplings between the Z boson and the photon. Zγ couplings vanish at tree level and are heavily suppressed at higher orders; hence any evidence of couplings indicates new physics. Measurements are performed using data corresponding to an integrated luminosity of 4.9  fb(-1) in the Z→νν¯ decay channel and 5.1  fb(-1) in the Z→l(+)l(-) (l=μ, e) decay channels. The combination of these measurements provides the most stringent limits to date on Zγ trilinear gauge couplings. Using an energy scale of Λ=1.5  TeV to allow for a direct comparison with previous measurements, we find limits on the CP-conserving parameters that describe Zγ couplings to be |h(3)(γ,Z)|<0.022 and |h(4)(γ,Z)|<0.0009. These results are consistent with standard model predictions.

Laminar shear stress promotes endothelial cell migration and inhibits cell apoptosis in the presence of hydroxyurea

Cell migration plays important roles in both physiological and pathological processes. Recent studies have shown that hydroxyurea, which is an anti-proliferative inhibitor, can affect cell morphology and specific gene expression of endothelial cells (ECs). In vivo, the functions of ECs are modulated by shear stress. It is well known that shear stress can have effects on EC migration by affecting cell morphology, cytoskeletal arrangement and cell-cell junction, and activating mechanosensors, inducing the changes of signaling pathways, and then increasing or decreasing the expression of gene and protein. However, the influences of hydroxyurea on EC function under shear stress are still unclear. In present study, we investigated the effects of hydroxyurea on EC proliferation, apoptosis and migration under laminar shear stress. The results showed that hydroxyurea prevented growth of ECs in a dose-dependent manner. Hydroxyurea at 2 mM completely inhibited the proliferation of ECs. The results also demonstrated that hydroxyurea induced EC apoptosis, but it was inhibited by 15.27 dyn/cm2 laminar shear stress. Furthermore, shear stress induced cell migration in the presence of hydroxyurea. Therefore, 2 mM hydroxyurea, which completely inhibited the proliferation of HUVECs, could be used to eliminate any confounding effect of shear stress on proliferation in shear stress-induced cell migration. These results also do confirm that shear stress plays important roles in achieving and maintaining the stabilization of ECs.

First search for multijet resonances in sqrt(s) = 1.96 TeV pp collisions

We present the first model independent search for three-jet hadronic resonances within multijet events in sqrt(s) = 1.96  TeV pp collisions at the Fermilab Tevatron using the CDF II detector. Pair production of supersymmetric gluinos and squarks with hadronic R-parity violating decays is employed as an example of a new physics benchmark for this signature. Selection criteria based on the kinematic properties of an ensemble of jet combinations within each event help to extract signal from copious QCD background. No significant excess outside the top quark mass window is observed in data with an integrated luminosity of 3.2  fb(-1). We place 95% confidence level limits on the production cross section σ(pp → XX')×BR(gg → 3  jet + 3  jet) where X, X' = g, q, or q, with q, q → g + jet, as a function of gluino mass, in the range of 77  GeV/c2 to 240  GeV/c2.

Search for a very light CP-odd Higgs boson in top quark decays from pp collisions at sqrt(s)]=1.96 TeV

We present the results of a search for a very light CP-odd Higgs boson a(1)(0) originating from top quark decays t → H(±)b → W(±(*)) a(1)(0)b, and subsequently decaying into τ+ τ-. Using a data sample corresponding to an integrated luminosity of 2.7  fb(-1) collected by the CDF II detector in pp collisions at 1.96 TeV, we perform a search for events containing a lepton, three or more jets, and an additional isolated track with transverse momentum in the range 3 to 20  GeV/c. Observed events are consistent with background sources, and 95% C.L. limits are set on the branching ratio of t → H(±)b for various masses of H(±) and a(1)(0).

First measurement of the angular coefficients of Drell-Yan e(+)e(-) pairs in the Z mass region from pp¯ collisions at √s=1.96 TeV

We report on the first measurement of the angular distributions of final state electrons in pp¯ → γ*/Z → e(+)e(-) + X events produced in the Z boson mass region at √s1.96 TeV. The data sample collected by the CDF II detector for this result corresponds to 2.1  fb(-1) of integrated luminosity. The angular distributions are studied as a function of the transverse momentum of the electron-positron pair and show good agreement with the Lam-Tung relation, consistent with a spin-1 description of the gluon, and demonstrate that, at high values of the transverse momentum, Z bosons are produced via quark-antiquark annihilation and quark-gluon Compton processes.

Assessment of cardiac diastolic dysfunction in HIV-infected people without cardiovascular symptoms in China

This study assessed cardiac diastolic dysfunction (DD) in HIV-infected subjects without cardiovascular symptoms in China. Eighty-four HIV-infected patients without cardiovascular symptoms were recruited and compared with 30 HIV-negative control subjects. Cardiac DD was evaluated using echocardiography including tissue Doppler imaging. DD was detected in 47.6% of AIDS patients and 42.8% of HIV-positive patients, which was significantly higher than in HIV-negative controls. After logistic regression analysis, HIV infection was independently correlated with cardiac DD (P < 0.05). Among HIV-positive subjects, logistic regression analysis showed that zidovudine exposure was associated with higher prevalence of DD (P < 0.05). Asymptomatic cardiac DD was observed frequently in HIV-infected subjects. HIV infection itself and zidovudine exposure were correlated with a higher prevalence of cardiac DD.

Search for production of heavy particles decaying to top quarks and invisible particles in pp collisions at √s = 1.96 TeV

We present a search for a new particle T' decaying to top quark via T' → t + X, where X is an invisible particle. In a data sample with 4.8  fb(-1) of integrated luminosity collected by the CDF II detector at Fermilab in pp collisions with √s = 1.96  TeV, we search for pair production of T' in the lepton + jets channel, pp → tt + X + X → ℓνbqq'b + X + X. We interpret our results primarily in terms of a model where T' are exotic fourth generation quarks and X are dark matter particles. Current direct and indirect bounds on such exotic quarks restrict their masses to be between 300 and 600  GeV/c2, the dark matter particle mass being anywhere below m(T'). The data are consistent with standard model expectations, and we set 95% confidence level limits on the generic production of T'T' → tt + X + X. For the dark matter model we exclude T' at 95% confidence level up to m(T') = 360  GeV/c2 for m(X) ≤ 100  GeV/c2.

Measurements of direct CP violating asymmetries in charmless decays of strange bottom mesons and bottom baryons

We report measurements of direct CP-violating asymmetries in charmless decays of neutral bottom hadrons to pairs of charged hadrons with the upgraded Collider Detector at the Fermilab Tevatron. Using a data sample corresponding to 1 fb(-1) of integrated luminosity, we obtain the first measurements of direct CP violation in bottom strange mesons, A(CP)(B(s)(0)→K(-)π(+))=+0.39±0.15(stat)±0.08(syst), and bottom baryons, A(CP)(Λ(b)(0)→pπ(-))=+0.03±0.17(stat)±0.05(syst) and A(CP)(Λ(b)(0)→pK(-))=+0.37±0.17(stat)±0.03(syst). In addition, we measure CP violation in B(0)→K(+)π(-) decays with 3.5σ significance, A(CP)(B(0)→K(+)π(-))=-0.086±0.023(stat)±0.009(syst), in agreement with the current world average. Measurements of branching fractions of B(s)(0)→K(+)K(-) and B(0)→π(+)π(-) decays are also updated.

Invariant mass distribution of jet pairs produced in association with a W boson in pp collisions at sqrt[s]=1.96 TeV

We report a study of the invariant mass distribution of jet pairs produced in association with a W boson using data collected with the CDF detector which correspond to an integrated luminosity of 4.3  fb(-1). The observed distribution has an excess in the 120-160  GeV/c(2) mass range which is not described by current theoretical predictions within the statistical and systematic uncertainties. In this Letter, we report studies of the properties of this excess.

Measurement of the forward-backward asymmetry in the B→K*μ(+)μ(-) decay and first observation of the B(s)0→ϕμ(+)μ(-) decay

We reconstruct the rare decays B(+)→K(+)μ(+0μ(-0, B90)→K*(892)(0)μ(+)μ(-), and B(s)(0)→ϕ(1020)μ(+)μ(-) in a data sample corresponding to 4.4  fb(-1) collected in pp collisions at √[s]=1.96  TeV by the CDF II detector at the Tevatron Collider. Using 121±16 B(+)→K(+)μ(+)μ(-) and 101±12 B(0)→K(*0)μ(+)μ(-) decays we report the branching ratios. In addition, we report the differential branching ratio and the muon forward-backward asymmetry in the B(+) and B(0) decay modes, and the K(*0) longitudinal polarization fraction in the B(0) decay mode with respect to the squared dimuon mass. These are consistent with the predictions, and most recent determinations from other experiments and of comparable accuracy. We also report the first observation of the B(s)(0)→ϕμ(+)μ(-) decay and measure its branching ratio BR(B(s)(0)→ϕμ(+)μ(-))=[1.44±0.33±0.46]×10(-6) using 27±6 signal events. This is currently the most rare B(s)(0) decay observed.

Measurement of the mass difference between t and t quarks

We present a direct measurement of the mass difference between t and t quarks using tt candidate events in the lepton+jets channel, collected with the CDF II detector at Fermilab's 1.96 TeV Tevatron pp Collider. We make an event by event estimate of the mass difference to construct templates for top quark pair signal events and background events. The resulting mass difference distribution of data is compared to templates of signals and background using a maximum likelihood fit. From a sample corresponding to an integrated luminosity of 5.6  fb(-1), we measure a mass difference, ΔM(top) = M(t) - M(t) = -3.3 ± 1.4(stat) ± 1.0(syst)  GeV/c2, approximately 2 standard deviations away from the CPT hypothesis of zero mass difference.

Search for heavy bottomlike quarks decaying to an electron or muon and jets in pp collisions at √s = 1.96 TeV

We report the most sensitive direct search for pair production of fourth-generation bottomlike chiral quarks (b') each decaying promptly to tW. We search for an excess of events with an electron or muon, at least five jets (one identified as due to a b or c quark), and an imbalance of transverse momentum by using data from pp collisions collected by the CDF II detector at Fermilab with an integrated luminosity of 4.8  fb(-1). We observe events consistent with background expectation, calculate upper limits on the b' pair-production cross section (σ(bb')) ≲30  fb for m(b') > 375  GeV/c2), and exclude m(b') < 372  GeV/c2 at 95% confidence level assuming a 100% branching ratio of b' to tW.

Measurement of b hadron lifetimes in exclusive decays containing a J/ψ in pp collisions at √s=1.96 TeV

We report on a measurement of b-hadron lifetimes in the fully reconstructed decay modes B(+)→J/ψK(+), B⁰→J/ψK*(892)⁰, B⁰→J/ψK(s)⁰, and Λ(b)⁰→J/ψΛ⁰ using data corresponding to an integrated luminosity of 4.3 fb⁻¹, collected by the CDF II detector at the Fermilab Tevatron. The measured lifetimes are τ(B(+))=[1.639±0.009(stat)±0.009(syst)] ps, τ(B⁰)=[1.507±0.010(stat)±0.008(syst)] ps, and τ(Λ(b)⁰)=[1.537±0.045(stat)±0.014(syst)] ps. The lifetime ratios are τ(B(+))/τ(B⁰)=[1.088±0.009(stat)±0.004(syst)] and τ(Λ(b)⁰)/τ(B⁰)=[1.020±0.030(stat)±0.008(syst)]. These are the most precise determinations of these quantities from a single experiment.

Search for high mass resonances decaying to muon pairs in √s=1.96 TeV pp collisions

We present a search for a new narrow, spin-1, high mass resonance decaying to μ(+)μ⁻+X, using a matrix-element-based likelihood and a simultaneous measurement of the resonance mass and production rate. In data with 4.6 fb⁻¹ of integrated luminosity collected by the CDF detector in pp collisions at √s=1960 GeV, the most likely signal cross section is consistent with zero at 16% confidence level. We therefore do not observe evidence for a high mass resonance and place limits on models predicting spin-1 resonances, including M>1071 GeV/c² at 95% confidence level for a Z' boson with the same couplings to fermions as the Z boson.

The expression of Sirtuins 1 and 4 in peripheral blood leukocytes from patients with type 2 diabetes

This study was designed to investigate the relationship between SIRTs 1 and 4 in peripheral blood leukocytes (PBLs) and human type 2 diabetes mellitus (T2DM). SIRTs 1 and 4 have been confirmed to be associated with homeostasis of glucose/lipid metabolism, but their roles in T2DM are still poorly understood. Peripheral blood and biochemical data were collected from 52 healthy individuals (normal control group, NC group) and 113 cases of T2DM patients. Immunocytochemical staining was used to detect SIRT1 and SIRT4 and reverse transcription polymerase chain reaction (RT-PCR) was used to detect SIRT1 or SIRT4 mRNA levels in PBLs. Immunocytochemical staining showed that SIRT1 is expressed in both nucleus and cytoplasm, and SIRT4 in the cytoplasm of granulocytes and monocytes. No SIRT1 or SIRT4 was found in lymphocytes. RT-PCR showed that SIRT1 and SIRT4 mRNA levels in T2DM group were lower than those in NC group (P&lt;0.01). Correlation analysis showed that there is a negative correlation between SIRTs 1 and 4 and fasting plasma glucose (FPG) (P&lt;0.05) (r= -0.161 and -0.156), a positive correlation between SIRT4 mRNA levels and triglyceride (TG)/lipoprotein a (LPa) levels (P&lt;0.05), and a negative correlation between SIRT4 mRNA levels and high density lipoprotein cholesterol (HDL) (P&lt;0.05). SIRTs 1 and 4 may have a role in the pathogenesis of T2DM and their expression in granulocytes and monocytes may indirectly reflect the homeostasis of glucose/lipid metabolism in T2DM.

Cancer targeting Gene-Viro-Therapy of liver carcinoma by dual-regulated oncolytic adenovirus armed with TRAIL gene

Liver cancer is a common and aggressive malignancy, but available treatment approaches remain suboptimal. Cancer targeting Gene-Viro-Therapy (CTGVT) has shown excellent anti-tumor effects in a preclinical study. CTGVT takes advantage of both gene therapy and virotherapy by incorporating an anti-tumor gene into an oncolytic virus vector. Potent anti-tumor activity is achieved by virus replication and exogenous expression of the anti-tumor gene. A dual-regulated oncolytic adenoviral vector designated Ad·AFP·E1A·E1B (Δ55) (Ad·AFP·D55 for short thereafter) was constructed by replacing the native viral E1A promoter with the simian virus 40 enhancer/α-fetoprotein (AFP) composite promoter (AFPep) based on an E1B-55K-deleted construct, ZD55. Ad·AFP·D55 showed specific replication and cytotoxicity in AFP-positive hepatoma cells. It also showed enhanced safety in normal cells when compared with the mono-regulated vector ZD55. To improve the anti-hepatoma activities of the virus, the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) gene was introduced into Ad·AFP·D55. Ad·AFP·D55-TRAIL exhibited remarkable anti-tumor activities in vitro and in vivo. Treatment with Ad·AFP·D55-TRAIL can induce both autophagy owing to the Ad·AFP·D55 vector and caspase-dependent apoptosis owing to the TRAIL protein. Therefore, Ad·AFP·D55-TRAIL could be a potential anti-hepatoma agent with anti-tumor activities due to AFP-specific replication and TRAIL-induced apoptosis.

Quality of life and psychologic distress of recipients after adult living-donor liver transplantation (LDLT)-A study from mainland China

This cross-sectional study investigated potential factors impacting quality of life in 125 recipients after living-donor liver transplantation (LDLT). Health-related quality of life (HRQoL) was measured by using the Chinese version of Medical Outcomes Study Short Form-36 (SF-36), and psychologic symptoms by using the Symptom Checklist-90-Revised (SCL-90-R). Clinical and demographic data were collected from the records of the Chinese Liver Transplant Registry and via questionnaire. A total of 102 recipients (81.6%) completed the questionnaires. All SF-36 domain scores (except the mental health score) were lower in the study than in the general population of Sichuan. The mental quality of life was significantly lower in female than in male subjects (P = .000). Regarding the role-physical (P = .016), social functioning (P = .000), and role-emotional (P = .004) domains, recipients >1 year after transplantation scored higher than those <1 year. Bodily pain scores were lower in recipients with prior acute liver failure than those with hepatic carcinoma or hepatic cirrhosis (P = .032). Social functioning was poorer in recipients with than in those without complications (P = .039). Mental component summary scale (MCS) scores and some of physical component summary scale (PCS) significantly correlated with symptom dimension scores of the SCL-90-R (P < .05). In conclusion, gender, time since transplant, etiology of disease, complications, occupation, and some psychologic symptoms were possible factors influencing postoperative HRQoL of LDLT recipients.

Confirmation of the X(1835) and observation of the resonances X(2120) and X(2370) in J/ψ→γπ+π-η'

With a sample of (225.2±2.8)×10(6) J/ψ events registered in the BESIII detector, J/ψ→γπ(+)π(-)η(') is studied using two η(') decay modes: η(')→π(+)π(-)η and η(')→γρ(0). The X(1835), which was previously observed by BESII, is confirmed with a statistical significance that is larger than 20σ. In addition, in the π(+)π(-)η(') invariant-mass spectrum, the X(2120) and the X(2370), are observed with statistical significances larger than 7.2σ and 6.4σ, respectively. For the X(1835), the angular distribution of the radiative photon is consistent with expectations for a pseudoscalar.

Causes of moderate to large pericardial effusion requiring pericardiocentesis in 140 Han Chinese patients

BACKGROUND

Causes of pericardial effusion requiring pericardiocentesis are very complex; a summary of 140 patients, especially those having iatrogenic pericardial effusion, is rare.

METHODS

We prospectively analyzed the clinical data and etiology of moderate to large pericardial effusion requiring pericardiocentesis and drainage in 140 consecutive Han Chinese patients from January 2007 to December 2009.

RESULTS

Pericardiocentesis was successfully performed and effective in all patients. There were 9 cases with transudates, while the remaining 131 cases were diagnosed with exudates (neoplastic in 54 patients, tuberculous in 40 patients, 9 cases of connective tissue diseases, 12 cases undergoing cardiac catheterization, and 8 cases of acute myocardial infarction). Among the 54 malignancies, 30 patients had lung cancer, 7 had breast cancer, and 4 had liver cancer. No differences in the clinical characteristics and the results of routine and biochemistry studies in the pericardial fluid between tuberculous and malignant groups were found. Of the 12 patients undergoing cardiac catheterization, 6 cases had undergone catheter ablation for tachycardia and 4 cases had undergone percutaneous coronary intervention. The 6 patients undergoing catheter ablation were women and the ratio of pericardial effusion was higher in women (6/436) than in men (0/462; p<0.05). Pericardiocentesis and drainage was effective in the 6 patients who underwent catheter ablation, and the remaining 6 patients underwent surgical intervention after pericardiocentesis and drainage. All 8 patients with acute myocardial infarction died during hospitalization.

CONCLUSION

In China, most moderate to large pericardial effusions requiring pericardiocentesis and drainage were exudates and bloody, which were mainly caused by malignancy and tuberculosis. However, the incidence of iatrogenic pericardial effusion has been increasing and should not be ignored. Pericardiocentesis and drainage were effective.

Phase I study of everolimus (RAD001) with irinotecan (Iri) and cetuximab (C) in second-line metastatic colorectal cancer: Hoosier Oncology Group GI05-102

523

Background: Preclinically, mTOR and EGFR inhibitors are synergistic. We hypothesize that the mTOR inhibitor RAD001 would enhance efficacy and prevent resistance when added to an anti-EGFR agent. The purpose of the phase I portion of this study was to determine the safety and maximum tolerated dose (MTD) of daily RAD001 combined with weekly Iri and C in mCRC.

Methods: Pts who failed first-line therapy, including an Iri-regimen, were treated with Iri 125 mg/m2 weekly x 2 every 3 weeks, C 400 mg/m2 loading dose, then 250 mg/m2 weekly, and escalating doses of RAD001 orally: 5 mg qod, 5 mg qd and 10 mg qd during 21-day cycles, with a “3+3” design. The study was amended after the first 9 pts enrolled, to include stopping rules for excessive toxicity beyond what was expected for diarrhea, nausea/vomiting and febrile neutropenia due to Iri, and skin rash due to C. Enrollment excluded pts with UGT1A1*28, but allowed KRAS mutated mCRC. RAD001 PK was done on C2D1, and archival tumors were analyzed for pharmacodynamic markers.

Results: 28 pts were enrolled, median age 61 y (25-77), 15 male, ECOG PS 0/1 (19/9). Reasons for treatment discontinuation were: PD (7), adverse events (AEs) (6), pt withdrawal, symptomatic deterioration and non-compliance (1 each). Prior to study's amendment* (n=9), 3 pts were not evaluable for DLT due to: Iri intolerance after one dose (1), non-compliance (1) and gr 3 C infusion reaction (1). DLTs and number of cycles are listed in Table. Following protocol amendment, 2 pts had DLT in cohort 3 (gr 3 mucositis), thus the MTD was 5 mg RAD001. The most common grade 3/4 AEs were: diarrhea (10), neutropenia (5), fatigue (4), acne-rash (4), mucositis (2), nausea (2), vomiting (1). Among 19 pts evaluable for response, there were 1 CR, 2 PR, (RR 16%), 9 SD (47%), 7 PD (37%). PK and pharmacodynamic data is ongoing.

Conclusions: The MTD of RAD001 of 5 mg QD with Iri/C weekly is safe and clinically active. A randomized phase II study is near starting accrual.

[Table: see text]

[Table: see text]