53,410 research outputs found
Measurement of the ratio of branching fractions B(B0→K∗0γ )/B(B0s→φγ ) and the directCP asymmetry inB 0→K∗0γ
No full textThe ratio of branching fractions of the radiative B decays B0→K⁎0γ and B0s→ϕγ has been measured using an integrated luminosity of 1.0 fb−1 of pp collision data collected by the LHCb experiment at a centre-of-mass energy of s√=7TeV. The value obtained is
B(B0→K⁎0γ)B(B0s→ϕγ)=1.23±0.06(stat.)±0.04(syst.)±0.10(fs/fd),
where the first uncertainty is statistical, the second is the experimental systematic uncertainty and the third is associated with the ratio of fragmentation fractions fs/fd. Using the world average value for B(B0→K⁎0γ), the branching fraction B(B0s→ϕγ) is measured to be (3.5±0.4)×10−5.
The direct CP asymmetry in B0→K⁎0γ decays has also been measured with the same data and found to be
ACP(B0→K⁎0γ)=(0.8±1.7(stat.)±0.9(syst.))%.
Both measurements are the most precise to date and are in agreement with the previous experimental results and theoretical expectations
b-Glycosyl Azides as Substratesfor a-Glycosynthases: Preparationof Efficient a-L-Fucosynthases
No full textFucose-containingoligosaccharides play a central role in physio-pathological events, and fucosylated oligosaccharides have interesting potential applications in biomedicine. No methods for the large-scale production of oligosaccharides are currently available, but the chemo-enzymatic approach is very romising. Glycosynthases, mutated glycosidases that synthesize oligosaccharides in high yields, have been demonstrated to be an interesting alternative. However, examples of glycosynthases available so far are restricted to a limited number of glycosidases families and to only one retaining a-glycosynthase. We show here that newmutants of two a-L-fucosidases are efficient a-L-fucosynthases. The approach shown utilized b-L-fucopyranosyl azide as donor substrate leading to transglycosylation yields up to 91%. This is the first method exploiting a b-glycosyl azide donor for a-glycosynthases; its applicability to the glycosynthetic methodology in a wider perspective is presented
Evidence for the decay B0→J/ψω and measurement of the relative branching fractions of meson decays to J/ψη and J/ψη′
No full textFirst evidence of the B 0 → J / ψ ω decay is found and the B s 0 → J / ψ η and B s 0 → J / ψ η ′ decays are studied using a dataset corresponding to an integrated luminosity of 1.0 fb -1 collected by the LHCb experiment in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV. The branching fractions of these decays are measured relative to that of the B 0 → J / ψ ρ 0 decay:frac(B (B 0 → J / ψ ω), B (B 0 → J / ψ ρ 0)) = 0.89 ± 0.19 (stat) - 0.13 + 0.07 (syst),frac(B (B s 0 → J / ψ η), B (B 0 → J / ψ ρ 0)) = 14.0 ± 1.2 (stat) - 1.5 + 1.1 (syst) - 1.0 + 1.1 (frac(f d, f s)),frac(B (B s 0 → J / ψ η ′), B (B 0 → J / ψ ρ 0)) = 12.7 ± 1.1 (stat) - 1.3 + 0.5 (syst) - 0.9 + 1.0 (frac(f d, f s)), where the last uncertainty is due to the knowledge of f d / f s, the ratio of b-quark hadronization factors that accounts for the different production rate of B 0 and B s 0 mesons. The ratio of the branching fractions of B s 0 → J / ψ η ′ and B s 0 → J / ψ η decays is measured to befrac(B (B s 0 → J / ψ η ′), B (B s 0 → J / ψ η)) = 0.90 ± 0.09 (stat) - 0.02 + 0.06 (syst)
Measurement of b-hadron masses
No full textMeasurements of b-hadron masses are performed with the exclusive decay modes B +→J/ψK +, B 0→J/ψK +, B0→J/ψKS0, Bs0→J/ψφ and Λb0→J/ψΛ using an integrated luminosity of 35pb -1 collected in pp collisions at a centre-of-mass energy of 7 TeV by the LHCb experiment. The momentum scale is calibrated with J/ψ→μ +μ - decays and verified to be known to a relative precision of 2 ×10 -4 using other two-body decays. The results are more precise than previous measurements, particularly in the case of the Bs0 and Λb0 masses
Measurement of the ZZ production cross section and Z -> l(+)l(-)l '(+)l '(-) branching fraction in pp collisions at root s=13TeV
No full textFour-lepton production in proton-proton collisions, pp -> (Z/gamma*)(Z/gamma*)-> l(+)l(-)l '(+)l '(-), where l,l '(-) = e or mu, is studied at a center-of-mass energy of 13 TeV with the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 2.6fb(-1). The ZZ production cross section, sigma(pp -> ZZ) = 14.6(-1.8)(+1.9)(stat)(-0.3)(+0.5) (syst) +/-0.2 (theo) +/-0.4 (lumi) pb, is measured for events with two opposite-sign, sameflavor lepton pairs produced in the mass region 60 < m(l+l-) m (l'+l'-) < 120GeV. The Z boson branching fraction to four leptons is measured to be B(Z -> l(+)l(-)l '(+)l '(-)) = 4.9(-0.7)(+0.8)(stat)(-0.2)(+0.3)(syst)(-0.1)(+0.2)(theo) +/- 0.1 (lumi) x10(-6) for the four-lepton invariant mass in the range 80 < m(l+)l-l'+l' < 100GeVand dilepton mass m(l+l-) > 4GeVfor all opposite-sign, same-flavor lepton pairs. The results are in agreement with standard model predictions. (C) 2016 The Author. Published by Elsevier B. V. This is an open access article under the CC BY licens
B hepatitis and liver transplantation
No full textHerein is reported our experience in treating with a liver transplant 14 HBsAg+ patients affected by end-stage liver disease; among these, nine patients were or had been also superinfected with HDV. An attempt has been made to evaluate the course of possible HBV reinfection and its correlation to HDV coinfection in patients who survived more than 3 months. Our results suggest that OLTX must also be performed in HBsAg carriers, even if serological signs of HBV virulence or HDV coinfection are present, to have a good outcome and quality of life. OLTX must also be performed if patients develop posttransplant B/D viral hepatitis recurrence. Future efforts must be directed toward best identifying recurrences, improving active and passive prophylaxis-mainly the long-term one-monitoring HBsAG titer, and evaluating the oppportunity of pretransplant treatment with interferon, to which HDV especially seems to be sensitive
Reductive catalytic dehalogenation of light chlorocarbons
No full textSeveral palladium and platinum supported catalysts have been employed in the gas-phase dehalogenation of chloromethanes (CCl4, CHCl3 and CH2Cl2) and chlorobenzene by using molecular hydrogen under mild conditions. A new porous glass material (Vycor) has been found to be a promising carrier for platinum in the selective hydrogenation of CCl4 to CHCl3 ensuring high selectivity and durability. Palladium on alumina showed the best performance in the deep dehalogenation of CHCl3 and CH2Cl2 to CH4 and HCl. Chlorobenzene dehalogenation is a fast reaction with many catalytic systems. However, palladium catalysts produce mostly C6H6, whereas platinum ones induce overhydrogenation to cyclohexane. A comparison of reductive and oxidative processes for chloromethane disposal is presented. (C) 1999 Elsevier Science B.V. All rights reserved
Human eosinophil chemotaxis and selective in vivo recruitment by sphingosine 1-phosphate.
No full textProc Natl Acad Sci U S A. 2004 Jul 27;101(30):11170-5. Epub 2004 Jul 14.
Human eosinophil chemotaxis and selective in vivo recruitment by sphingosine 1-phosphate.
Roviezzo F, Del Galdo F, Abbate G, Bucci M, D'Agostino B, Antunes E, De Dominicis G, Parente L, Rossi F, Cirino G, De Palma R.
Dipartimento di Scienze Farmaceutiche, Università di Salerno, 84084 Salerno, Italy.
Sphingosine 1-phosphate (S1P) is a sphingolipid mediator that is involved in diverse biological functions. Local administration of S1P causes inflammation coupled to a large eosinophil (EO) recruitment in the rat-paw tissue. The inflammatory response is accompanied by an increase in S1P receptors, namely
S1P(1), S1P(2), S1P(3), and by an enhanced expression of CCR3, which is the main chemokine receptor known to be involved in EO function. Human EOs constitutively
express S1P(1) and, at a lower extent, S1P(2), S1P(3) receptors. S1P in vitro causes cultured human EO migration and an increase in S1P receptor mRNA copies and strongly up-regulates CCR3 and RANTES (regulated on activation, normal T cell-expressed and secreted) message levels; in particular CCR3 is up-regulated 18,000-fold by S1P. A blocking anti-CCR3 Ab inhibits S1P-induced chemotaxis, implying that S1P acts as specific recruiting signal for EOs not only through its
own receptors but also through CCR3. These results show that S1P is involved in EO chemotaxis and contribute to shed light on the complex mechanisms underlying EO recruitment in several diseases such as asthma and some malignancies
Rhachomyces spiralis W. Rossi & M. Leonardi 2020, sp. nov.
No full text<i>Rhachomyces spiralis</i> W.Rossi & M.Leonardi, sp. nov. (Fig. 2B, C) <p> Differs from <i>Rhachomyces longissimus</i> Thaxt. for the very long lower appendages, for the very numerous and differently shaped upper appendages, and for the spiral twist of the thalli growing on the dorsal surface of the host.</p> <p> ETYMOLOGY. — From Latin <i>spiralis</i> which means spiral, because of the thalli spirally twisted when growing on the dorsal surface of the host.</p> <p> MATERIAL EXAMINED. — <b>China</b>. Guizhou, Quianxi County, Honglin Town, Luo Sai Dong, GZ/Qx/29, alt. 1445 m, on <i>Guizhaphaenops</i>, sp. (Coleoptera, Carabidae), 19.XI.2003, leg. L. Latella, S. Meggiorini & A. Bileddo (holo-, FI [FI WR3035]; para-, FI [FI WR3034]).</p> <p>MYCOBANK. — MB 831068.</p> DESCRIPTION <p>Axis of the receptacle distinctly spiral in thalli growing on the elytra and pronotum of the host insect, consisting of 19-38 cells; from slightly to distinctly curved and consisting of 12-31 cells when growing on other parts of the body. These cells are brown, usually much darker on the anterior side and along the septa, gradually enlarging from the foot to the base of the perithecium. The appendages originating from the lower cells of the axis are long, dark and stiff; those in the upper portion of the thallus are more numerous, much shorter and paler, with more slender and almost hyaline tips. Antheridial appendages very numerous, consisting of two brown cells terminated by an elongate, grayish antheridium bearing a slender and curved neck. Perithecium sessile, oblong, very slightly inflated below, light brown colored, regularly tapering to the darker, subconical tip and hyaline, blunt apex. Length of the receptacle in unstretched spiral thalli growing on elytra and pronotum: up to 790 µm; length of receptacles of thalli growing on other parts of the host 255-675 µm; perithecium 130-150 × 40-42 µm; antheridial appendages 45-50 µm.</p> <p>REMARKS</p> <p> The spiralized habitus of thalli growing on the hosts’ dorsal surface is unique among the species in the genus <i>Rhachomyces</i> and resemble tiny corkscrews emerging from (or screwed upon) the insects (Fig. 2B). Because of the shape of the perithecium and the length of the receptacle, <i>R</i>. <i>spiralis</i>, sp. nov., bears a superficial resemblance with <i>R</i>. <i>longissimus</i>, parasitic on Carabidae Anchomenini in Central and South America (Proaño Castro & Rossi 2008; fig. 7). However, the sterile appendages and the antheridial appendages of the two species are very different.</p>Published as part of <i>Rossi, Walter & Leonardi, Marco, 2020, New Laboulbeniales from China (Ascomycota), pp. 1-7 in Cryptogamie, Mycologie 20 (1)</i> on page 4, DOI: 10.5252/cryptogamie-mycologie2020v41a1, <a href="http://zenodo.org/record/7814964">http://zenodo.org/record/7814964</a>
Hepatitis B associated coinfection and superinfection with delta agent: indistinguishable diseases with different outcome.
No full textAbstract
Markers of hepatitis B virus (HBV) and delta agent were prospectively tested in sera of 107 intravenous drug abusers with acute hepatitis positive for hepatitis B surface antigen (HBsAg) associated with delta infection and compared with the findings in addicts with acute classical hepatitis B. On the basis of the presence and titer of IgM antibody to hepatitis B core antigen, 86 of the addicts with delta infection had simultaneously acquired HBV and delta agent, and 21 were chronic carriers of HBsAg experiencing acute delta superinfection. The frequencies of biphasic and severe hepatitis were significantly higher (P less than .05) in delta agent-infected patients than in controls, but the acute clinical and biochemical features of the two varieties of delta disease were not distinguishable. However, in analogy to the clinical outcome of classical hepatitis B, all patients with nonfatal acute HBV/delta coinfection had self-limited illness, whereas 20 of 21 HBsAg carriers superinfected by delta agent developed chronic active hepatiti
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