Search for three-jet resonances in pp collisions at square root(s)=7 TeV

A search for three-jet hadronic resonance production in pp collisions at a center-of-mass energy of 7 TeV has been conducted by the CMS Collaboration at the LHC, using a data sample corresponding to an integrated luminosity of 35  pb(-1). Events with high jet multiplicity and a large scalar sum of jet transverse momenta are analyzed using a signature-based approach. The number of expected standard model background events is found to be in good agreement with the observed events. Limits on the cross section times branching ratio are set in a model of gluino pair production with an R-parity-violating decay to three quarks, and the data rule out such particles within the mass range of 200 to 280  GeV/c2.

Pressure-independent cerebrovascular remodelling and changes in myogenic reactivity in diabetic Goto-Kakizaki rat in response to glycaemic control

AIM

We have shown hypertrophic cerebrovascular remodelling in the Goto-Kakizaki (GK) rat model of diabetes. This study tested the hypotheses that (1) vascular remodelling develops as the disease progresses and alters myogenic reactivity of resistance vessels important for regulation of cerebral blood flow (CBF), and (2) glycaemic control prevents cerebrovascular remodelling and myogenic dysfunction.

METHODS

Middle cerebral artery (MCA) lumen diameter, media : lumen (M : L) ratio, cross-sectional area (CSA) and myogenic tone were measured in 10- and 18-week-old control Wistar and diabetic GK rats using pressurized arteriograph (n = 8-14/group). Mean arterial blood pressure (MAP) was measured with telemetry (n = 5/group). Additional GK rats were treated with metformin (300 mg kg(-1) day(-1) ) for glycaemic control starting at 7 weeks after the onset of diabetes until 18 weeks (n = 9).

RESULTS

In the control group, there was no difference in remodelling indices, myogenic tone or MAP between ages. Eighteen week diabetic rats displayed increased M : L ratio and CSA, but decreased lumen diameter and myogenic tone compared to 10-week GK or 18-week control rats. MAP increased starting around 10 weeks of age and remained slightly higher in the GK rats. Glycaemic control normalized M : L ratio, CSA, lumen diameter and myogenic tone with no effect on blood pressure.

CONCLUSIONS

These findings suggest that diabetic rats develop MCA remodelling as the disease progresses but this is associated with impaired myogenic reactivity which may ultimately affect CBF. Our results also provide evidence that glycaemic control is an effective therapeutic strategy to prevent cerebrovascular remodelling and dysfunction.

Measurement of the t-channel single top quark production cross section in pp collisions at √s=7 TeV

Electroweak production of the top quark is measured for the first time in pp collisions at √=7  TeV, using a data set collected with the CMS detector at the LHC and corresponding to an integrated luminosity of 36  pb⁻¹. With an event selection optimized for t-channel production, two complementary analyses are performed. The first one exploits the special angular properties of the signal, together with background estimates from the data. The second approach uses a multivariate analysis technique to probe the compatibility with signal topology expected from electroweak top-quark production. The combined measurement of the cross section is 83.6±29.8(stat+syst)±3.3(lumi)  pb, consistent with the standard model expectation.

Indications of suppression of excited Υ states in Pb-Pb collisions at √(s(NN))=2.76 TeV

A comparison of the relative yields of Υ resonances in the μ(+)μ(-) decay channel in Pb-Pb and pp collisions at a center-of-mass energy per nucleon pair of 2.76 TeV is performed with data collected with the CMS detector at the LHC. Using muons of transverse momentum above 4  GeV/c and pseudorapidity below 2.4, the double ratio of the Υ(2S) and Υ(3S) excited states to the Υ(1S) ground state in Pb-Pb and pp collisions, [Υ(2S+3S)/Υ(1S)](Pb-Pb)/[Υ(2S+3S)/Υ(1S)](pp), is found to be 0.31(-0.15)(+0.19)(stat)±0.03(syst). The probability to obtain the measured value, or lower, if the true double ratio is unity, is calculated to be less than 1%.

Changes in myofilament proteins, but not Ca²⁺ regulation, are associated with a high-fat diet-induced improvement in contractile function in heart failure

Pathological conditions such as diabetes, insulin resistance, and obesity are characterized by elevated plasma and myocardial lipid levels and have been reported to exacerbate the progression of heart failure (HF). Alterations in cardiomyocyte Ca(2+) regulatory properties and myofilament proteins have also been implicated in contractile dysfunction in HF. However, our prior studies reported that high saturated fat (SAT) feeding improves in vivo myocardial contractile function, thereby exerting a cardioprotective effect in HF. Therefore, we hypothesized that SAT feeding improves contractile function by altering Ca(2+) regulatory properties and myofilament protein expression in HF. Male Wistar rats underwent coronary artery ligation (HF) or sham surgery (SH) and were fed normal chow (SHNC and HFNC groups) or a SAT diet (SHSAT and HFSAT groups) for 8 wk. Contractile properties were measured in vivo [echocardiography and left ventricular (LV) cannulation] and in isolated LV cardiomyocytes. In vivo measures of contractility (peak LV +dP/dt and -dP/dt) were depressed in the HFNC versus SHNC group but improved in the HFSAT group. Isolated cardiomyocytes from both HF groups were hypertrophied and had decreased percent cell shortening and a prolonged time to half-decay of the Ca(2+) transient versus the SH group; however, SAT feeding reduced in vivo myocyte hypertrophy in the HFSAT group only. The peak velocity of cell shortening was reduced in the HFNC group but not the HFSAT group and was positively correlated with in vivo contractile function (peak LV +dP/dt). The HFNC group demonstrated a myosin heavy chain (MHC) isoform switch from fast MHC-α to slow MHC-β, which was prevented in the HFSAT group. Alterations in Ca(2+) transients, L-type Ca(2+) currents, and protein expression of sarco(endo)plasmic reticulum Ca(2+)-ATPase and phosphorylated phospholamban could not account for the changes in the in vivo contractile properties. In conclusion, the cardioprotective effects associated with SAT feeding in HF may occur at the level of the isolated cardiomyocyte, specifically involving changes in myofilament function but not sarcoplasmic reticulum Ca(2+) regulatory properties.

High density and scale-up cultivation of recombinant CHO cell line and hybridomas with porous microcarrier Cytopore

Using porous microcarrier Cytopore and a low-serum medium supplement BIGBEF-3, we have successfully cultivated recombinant CHO cell line CL-11G producing prourokinase and hybridomas producing anti-prourokinase monoclonal antibody in Celligen 1.5 or 5 L bioreactor. The cell density obtained ranged from 1 to 2 x 107 cells mL-1. The yields of prourokinase and monoclonal antibody increased with increasing cell density. As the cells could spontaneously release from and reattach to porous microcarriers, it was very easy to scale-up the cultivation. Thus the bead to bead cell transfer method has been used to scale up the cultivation of CL-11G cells to a 20 L reactor-scale for the pilot production of prourokinase, and also to scale-up the culture of hybridomas for the production of monoclonal antibody for the purification of prourokinase.

A study to establish whether food-based approaches can improve serum iron levels in child-bearing aged women

BACKGROUND

Iron-deficiency anaemia is particularly prevalent in pregnancy. The present study aimed to determine whether functional bread containing teff flour (i.e. naturally rich in iron) could be an alternative way of improving iron status. However, before testing whether its consumption can improve pregnancy iron status, the bio-availability of iron was determined in a sample of nonpregnant women.

METHODS

Fifty-eight women (20-50 years) were recruited from the University. Blood samples were taken at baseline to assess iron status and participants were screened to account for other factors affecting iron status. Twenty-four participants (haemoglobin 9.5-14.0g dL(-1) ) were recruited to take part in the intervention and allocated to five groups: (i) control bread (CB); (ii) teff bread (TB); (iii) TB+level 1 phytase (TB+P1); (iv) TB+level 2 phytase (TB+P2); or (v) a supplement containing 10 mg of ferrous sulphate. Venous blood samples were taken before the intervention and after 180-210min, aiming to determine changes in serum iron.

RESULTS

Consuming three or four slices of TB provided statistically significantly more iron (7.6mg) than CB (5.1mg) (P<0.001). Because participants were fasted, serum iron levels declined in all bread groups (average -1.5μm), although the smallest reduction was observed in the TB+P2 group (-0.3 μm). The area-under-the-curve from baseline to 210min was lower in the TB+P2 (-78.8μmol min L(-1) ) group compared to the other bread interventions, indicating higher levels of iron absorption in this group.

CONCLUSIONS

The results obtained in the present study show that TB consumption may help to maintain serum iron levels, especially when phytase is added. The findings from the study also demonstrate there may be potential to further improve the bio-availability of iron from non-haem food sources.

Measurement of the polarization of W bosons with large transverse momenta in W + jets events at the LHC

A first measurement of the polarization of W bosons with large transverse momenta in pp collisions is presented. The measurement is based on 36 pb⁻¹ of data recorded at √s = 7 TeV by the CMS detector at the LHC. The left-handed, right-handed, and longitudinal polarization fractions (f(L), f(R), and f₀, respectively) of W bosons with transverse momenta larger than 50 GeV are determined by using decays to both electrons and muons. The muon final state yields the most precise measurement: (f(L) - f(R))⁻ = 0.240 ± 0.036(stat) ± 0.031(syst) and f₀⁻ = 0.183 ± 0.087(stat) ± 0.123(syst) for negatively charged W bosons and (f(L) - f(R))⁺ = 0.310 ± 0.036(stat) ± 0.017(syst) and f₀⁺ = 0.171 ± 0.085(stat) ± 0.099(syst) for positively charged W bosons. This establishes, for the first time, that W bosons produced in pp collisions with large transverse momenta are predominantly left-handed, as expected in the standard model.

Astroglial reaction to delta opioid peptide [D-Ala2, D-Leu5] enkephalin confers neuroprotection against global ischemia in the adult rat hippocampus

Delta opioid receptor (DOR) is essential for neuronal survival against hypoxic/ischemic damages. However, current understanding on how DOR activation affects astrocytic functions under ischemia remains incomplete. The present study investigated the astroglial responses to [d-Ala2, d-Leu5] enkephalin (DADLE) (a selective DOR agonist)-induced DOR activation after global cerebral ischemia. Adult male rats were preimplanted with intracerebral cannula and subjected to global ischemia for 10 min. The rats were divided into four groups: normal group (without any procedure), sham group (sham procedure with intracerebroventricular injection of ACSF), I/R group (ischemia procedure with intracerebroventricular injection of ACSF) and DAD-treated group (ischemia procedure with intracerebroventricular injection of DADLE). Hippocampal CA1 neuronal survival and activation of astrocytes were measured in the animals at 72 h post-ischemia. The distribution and phenotypes of p-Akt and active caspase-3 were also determined. The ischemic injury resulted in a significant neuronal loss and an increase in the dying astrocytes in the hippocampal CA1 region as compared with those in the sham animals (200.7±22.7/mm(2) vs. 6.6±3.1/mm(2), P<0.001). Improved neuronal survival in the DAD-treated animals was evident, which was accompanied by less dying astrocytes and enhanced astrocytes reaction with more active astrocytes than that in the I/R group (267.6±13.2/mm(2) vs. 157.0±18.1/mm(2), P<0.01) and a significantly increased immunoreactivity of p-Akt. However, the active caspase-3 positive cells were also evident in DAD-treated group (313.0±23.1/mm(2)) and significantly increased as compared with those of the sham group (159.0±15.8/mm(2), P<0.001) or I/R group (193.6±26.2/mm(2), P<0.01). Most of the active caspase-3-expressing cells were colabeled with glial fibrillary acidic protein (GFAP), an astrocytes marker. We conclude that the post-ischemic treatment with DADLE promotes beneficial astrocytes activation and induces astroglial apoptosis 72 h after reperfusion which may be involved in reducing their harmful effect to neurons survival.

Tissue-type plasminogen activator depletion affects the nasal mucosa matrix reconstruction in allergic rhinitis mice

BACKGROUND

The present study was designed to assess the function of tissue plasminogen activator (t-PA) expression in allergic rhinitis.

METHODS

Age-matched t-PA gene knock out (t-PA(-/-)) and wild type (WT) mice were sensitised four times, and then challenged for six weeks with ovalbumin. The controls were treated with saline instead of ovalbumin. The structural change in the nasal mucosa was investigated with haematoxylin and eosin stain and van Gieson staining. u-PA (urokinase-type plasminogen activator) and PAI-1 (plasminogen activator inhibitor) gene expression were measured by real time PCR. Matrix metalloproteinase-9 (MMP-9) expression was tested with Western blotting and with real time PCR.

RESULTS

After ovalbumin challenge for six weeks, compared with the WT group, t-PA depletion increased collagen deposition and gland hyperplasia. u-PA and PAI-1 gene expression increased both in t-PA(-/-) and in WT mice after ovalbumin treatment. MMP-9 expression decreased greatly after ovalbumin challenge in t-PA(-/-) mice.

CONCLUSION

t-PA affects the nasal mucosa matrix reconstruction process in allergic rhinitis, with which MMP-9 is involved.

Observation of turbulence suppression after electron-cyclotron-resonance-heating switch-off on the HL-2A tokamak

The formation of a transient internal transport barrier (ITB) is observed after the electron-cyclotron-resonance-heating (ECRH) switch-off in the HL-2A plasmas, characterized by transient increase of central electron temperature. The newly developed correlation reflectometer provided direct measurements showing reduction of turbulence in the region of steepened gradients for the period of ITB formation triggered by the ECRH switch-off. Furthermore, the reduction of core turbulence is correlated in time with the appearance of a low-frequency mode with a spectrally broad poloidal structure that peaks near zero frequency in the core region. These structures have low poloidal mode number, high poloidal correlation, and short radial correlation and are strongly coupled with high-frequency ambient turbulence. Observation indicates that these structures play important roles in the reduction of the core turbulence and in improvements of the core transport after the off-axis ECRH is turned off.

Measurement of the B0 production cross section in pp collisions at sqrt[s] = 7 TeV

Measurements of the differential production cross sections dσ/dpTB and dσ/dyB for B0 mesons produced in pp collisions at sqrt[s] = 7 TeV are presented. The data set used was collected by the CMS experiment at the LHC and corresponds to an integrated luminosity of 40 pb-1. The production cross section is measured from B0 meson decays reconstructed in the exclusive final state J/ψKS0, with the subsequent decays J/ψ → μ + μ - and KS0 → π+}π-. The total cross section for pTB>5 GeV and |yB|<2.2 is measured to be 33.2 ± 2.5 ± 3.5 μb, where the first uncertainty is statistical and the second is systematic.

Intestinal growth and morphology is associated with the increase in heat shock protein 70 expression in weaning piglets through supplementation with glutamine

The objectives of this study were to determine the effects of oral Gln supplementation on growth performance, intestinal morphology, and expression of heat shock protein (Hsp) 70 in weaning piglets. A total of 65 piglets after weaning at 21 d of age (d 0) were used in this experiment. Five piglets were randomly selected and euthanized initially at d 0 to determine baseline values for the expression of Hsp70 in the small intestine. The remaining piglets were randomly assigned to 1 of 2 treatments and received 0 or 1 g of oral Gln/kg of BW every 12 h. After piglets were humanely killed at d 3, 7, and 14 postweaning, the duodenum, jejunum, and ileum of piglets were sampled to evaluate intestinal morphology and the expression and localization of Hsp70. The results indicated that oral Gln supplementation increased plasma concentrations of Gln compared with those in control piglets (P < 0.05). Average daily gain and ADFI were greater in piglets orally supplemented with Gln than in control piglets during the whole period (P < 0.05). The incidence of diarrhea in piglets orally supplemented with Gln was 24% less than (P = 0.064) that in control piglets at 8 to 14 d after weaning. The weights of the jejunum and ileum were greater in piglets orally supplemented with Gln compared with those of control piglets relative to BW on d 14 postweaning (P < 0.05). The villus height and the villus height:crypt depth ratio in the jejunum and the ileum were greater in piglets receiving oral Gln on d 14 postweaning (P < 0.05) than in control piglets. These results indicate that Gln supplementation can influence the intestinal morphology of weaned piglets. The expression of hsp70 mRNA and Hsp70 proteins in the duodenum and jejunum was greater in piglets supplemented with Gln than in control piglets (P < 0.05). However, Gln supplementation had no effect on the expression of hsp70 mRNA and Hsp70 proteins in the ileum. Moreover, the localization of Hsp70 in the cytoplasm indicated that Hsp70 has a cytoprotective role in epithelial cell function and structure. These results indicate that Gln supplementation may be beneficial for intestinal health and development and may thus mitigate diarrhea and improve growth performance. The protective mechanisms of Gln in the intestine may be associated with the increase in Hsp70 expression.

Search for neutral minimal supersymmetric standard model Higgs bosons decaying to tau pairs in pp collisions at √s=7 TeV

A search for neutral minimal supersymmetric standard model (MSSM) Higgs bosons in pp collisions at the LHC at a center-of-mass energy of 7 TeV is presented. The results are based on a data sample corresponding to an integrated luminosity of 36  pb(-1) recorded by the CMS experiment. The search uses decays of the Higgs bosons to tau pairs. No excess is observed in the tau-pair invariant-mass spectrum. The resulting upper limits on the Higgs boson production cross section times branching fraction to tau pairs, as a function of the pseudoscalar Higgs boson mass, yield stringent new bounds in the MSSM parameter space.