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1.
Phys Rev Lett ; 108(15): 151801, 2012 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-22587241

RESUMEN

The decay B(s)(0) → J/ψK+ K- is investigated using 0.16 fb(-1) of data collected with the LHCb detector using 7 TeV pp collisions. Although the J/ψϕ channel is well known, final states at higher K+ K- masses have not previously been studied. In the K+ K- mass spectrum we observe a significant signal in the f(2)'(1525) region as well as a nonresonant component. After subtracting the nonresonant component, we find B(B(s)(0) → J/ψf(2)'(1525))/B(B(s)(0) → J/ψϕ) = (26.4 ± 2.7 ± 2.4)%.

2.
Phys Rev Lett ; 108(11): 111602, 2012 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-22540460

RESUMEN

A search for time-integrated CP violation in D(0)→h(-)h(+) (h=K, π) decays is presented using 0.62 fb(-1) of data collected by LHCb in 2011. The flavor of the charm meson is determined by the charge of the slow pion in the D(*+)→D(0)π(+) and D(*-)→D[over ¯](0)π(-) decay chains. The difference in CP asymmetry between D(0)→K(-)K(+) and D(0)→π(-)π(+), ΔA(CP)≡A(CP)(K(-)K(+))-A(CP)(π(-)π(+)), is measured to be [-0.82±0.21(stat)±0.11(syst)]%. This differs from the hypothesis of CP conservation by 3.5 standard deviations.

3.
Phys Rev Lett ; 108(16): 161801, 2012 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-22680708

RESUMEN

First observations of the Cabibbo-suppressed decays B(0) → D(+)K(-)π(+)π(-) and B(-) → D(0)K(-)π(+)π(-) are reported using 35 pb(-1) of data collected with the LHCb detector. Their branching fractions are measured with respect to the corresponding Cabibbo-favored decays, from which we obtain B(B(0) → D(+)K(-)π(+)π(-))/B(B(0) → D(+)π(-)π(+)π(-))=(5.9±1.1±0.5)×10(-2) and B(B(-) → D(0)K(-)π(+)π(-))/B(B(-) → D(0)π(-)π(+)π(-))=(9.4±1.3±0.9)×10(-2), where the uncertainties are statistical and systematic, respectively. The B(-) → D(0)K(-)π(+)π(-) decay is particularly interesting, as it can be used in a similar way to B(-) → D(0)K(-) to measure the Cabibbo-Kobayashi-Maskawa phase γ.

4.
Phys Rev Lett ; 108(18): 181806, 2012 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-22681061

RESUMEN

The angular distributions and the partial branching fraction of the decay B0 → K*0 µ+ µ- are studied by using an integrated luminosity of 0.37 fb(-1) of data collected with the LHCb detector. The forward-backward asymmetry of the muons, A(FB), the fraction of longitudinal polarization, F(L), and the partial branching fraction dB/dq2 are determined as a function of the dimuon invariant mass. The measurements are in good agreement with the standard model predictions and are the most precise to date. In the dimuon invariant mass squared range 1.00-6.00 GeV2/c4, the results are A(FB)=-0.06(-0.14)(+0.13)±0.04, F(L)=0.55±0.10±0.03, and dB/dq2=(0.42±0.06±0.03)×10(-7) c4/GeV2. In each case, the first error is statistical and the second systematic.

5.
Phys Rev Lett ; 108(10): 101601, 2012 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-22463398

RESUMEN

A search is performed for the lepton number violating decay B+ → h- µ+ µ+, where h- represents a K- or a π-, using an integrated luminosity of 36 pb(-1) of data collected with the LHCb detector. The decay is forbidden in the standard model but allowed in models with a Majorana neutrino. No signal is observed in either channel and limits of B(B+ → K- µ+ µ+) < 5.4×10(-8) and B(B+ → π- µ+ µ+) < 5.8×10(-8) are set at the 95% confidence level. These improve the previous best limits by factors of 40 and 30, respectively.

6.
Phys Rev Lett ; 108(10): 101803, 2012 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-22463401

RESUMEN

We present a measurement of the time-dependent CP-violating asymmetry in B(s)(0) → J/ψϕ decays, using data collected with the LHCb detector at the LHC. The decay time distribution of B(s)(0) → J/ψϕ is characterized by the decay widths Γ(H) and Γ(L) of the heavy and light mass eigenstates, respectively, of the B(s)(0) - B(s)(0) system and by a CP-violating phase ϕ(s). In a sample of about 8500 B(s)(0) → J/ψϕ events isolated from 0.37 fb(-1) of pp collisions at sqrt[s] = 7 TeV, we measure ϕ(s) = 0.15 ± 0.18(stat) ± 0.06(syst) rad. We also find an average B(s)(0) decay width Γ(s) ≡ (Γ(L) + Γ(H))/2 = 0.657 ± 0.009(stat) ± 0.008(syst) ps(-1) and a decay width difference ΔΓ(s) ≡ Γ(L) - Γ(H) = 0.123 ± 0.029(stat) ± 0.011(syst) ps(-1). Our measurement is insensitive to the transformation (ϕ(s),ΔΓ(s)) ↦ (π - ϕ(s), -ΔΓ(s)).

7.
Phys Rev Lett ; 108(20): 201601, 2012 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-23003138

RESUMEN

Using a data sample corresponding to an integrated luminosity of 0.35 fb-1 collected by LHCb in 2011, we report the first evidence of CP violation in the decays of Bs0} mesons to K±π∓ pairs, ACP(Bs0→Kπ)=0.27±0.08(stat)±0.02(syst), with a significance of 3.3σ. Furthermore, we report the most precise measurement of CP violation in the decays of B0 mesons to K±π∓ pairs, ACP(B0→Kπ)=-0.088±0.011(stat)±0.008(syst), with a significance exceeding 6σ.

8.
Phys Rev Lett ; 108(24): 241801, 2012 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-23004259

RESUMEN

The interference between the K+ K- S-wave and P-wave amplitudes in B(s)(0) → J/ψK+ K- decays with the K+ K- pairs in the region around the ϕ(1020) resonance is used to determine the variation of the difference of the strong phase between these amplitudes as a function of K+ K- invariant mass. Combined with the results from our CP asymmetry measurement in B(s)(0) → J/ψϕ decays, we conclude that the B(s)(0) mass eigenstate that is almost CP = +1 is lighter and decays faster than the mass eigenstate that is almost CP = -1. This determines the sign of the decay width difference ΔΓ(s) ≡ Γ(L) - Γ(H) to be positive. Our result also resolves the ambiguity in the past measurements of the CP violating phase ϕ(s) to be close to zero rather than π. These conclusions are in agreement with the standard model expectations.

9.
Phys Rev Lett ; 108(25): 251802, 2012 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-23004586

RESUMEN

The decay B(c)(+) → J/ψπ(+) π(-) π(+) is observed for the first time, using 0.8 fb(-1) of pp collisions at sqrt[s] = 7 TeV collected by the LHCb experiment. The ratio of branching fractions B(B(c)(+) → J/ψπ(+) π(-) π(+))/B(B(c)(+)→J/ψπ^{+}) is measured to be 2.41 ± 0.30 ± 0.33, where the first uncertainty is statistical and the second is systematic. The result is in agreement with theoretical predictions.

10.
Phys Rev Lett ; 107(21): 211801, 2011 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-22181871

RESUMEN

The relative abundance of the three decay modes B(0)→D(-)K(+), B(0)→D(-)π(+), and B(s)(0)→D(s)(-)π(+) produced in 7 TeV pp collisions at the LHC is determined from data corresponding to an integrated luminosity of 35 pb(-1). The branching fraction of B(0)→D(-)K(+) is found to be B(B(0)→D(-)K(+)) = (2.01 ± 0.18(stat) ± 0.14(syst)) × 10(-4). The ratio of fragmentation fractions f(s)/f(d) is determined through the relative abundance of B(s)(0)→D(s)(-)π(+) to B(0)→D(-)K(+) and B(0)→D(-)π(+), leading to f(s)/f(d) = 0.253 ± 0.017 ± 0.017 ± 0.020, where the uncertainties are statistical, systematic, and theoretical, respectively.

11.
Brain Res Mol Brain Res ; 69(2): 232-41, 1999 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-10366744

RESUMEN

The expression of c-fos, c-jun, jun-b, jun-d, srf and pc4 mRNA was examined after partial optic nerve crush in the adult rat retina by in situ hybridization. Optic nerve injury led exclusively to the upregulation of c-jun, with cellular label indicative for c-jun mRNA in the retinal ganglion cell layer after two days, three days and one week post-injury. This expression pattern was in accordance with the appearance of c-Jun immunoreactivity in retinal flat mounts. Injection of an antisense but not a missense oligonucleotide against c-jun after partial crush resulted in a reduced number of connected retinal ganglion cells (RGCs) as shown by retrograde labeling. Prelabeling of RGCs with fluorogold before optic nerve section and subsequent antisense targeting against c-jun, however, led to a slightly higher number of surviving but axotomized RGCs. C-Jun antibody staining of retinal whole mounts pre- or postlabeled after crush by intracollicular administration of fluorogold showed strong c-Jun immunoreactivity in connected RGCs and also in a population of disconnected RGCs. Double labeling with an antibody directed against the transcription factor ATF-2 revealed strong co-expression of c-Jun and ATF-2 in connected RGCs but not in axotomized cells. Taken together these data indicate that both RGCs in continuity and those in discontinuity with the superior colliculus respond both equally to the noxious stimulus with c-Jun expression. Moreover, the co-expression of c-Jun with high levels of ATF-2 appears to be essential for either the continuity or survival of RGCs which remain connected with their target. In disconnected RGCs, however, low levels of ATF-2 and the co-expression of c-Jun may be related to cell death.


Asunto(s)
Axones/metabolismo , Regulación de la Expresión Génica/fisiología , Proteínas del Tejido Nervioso/genética , Traumatismos del Nervio Óptico , Células Ganglionares de la Retina/metabolismo , Factor de Transcripción Activador 2 , Animales , Axotomía , Supervivencia Celular/fisiología , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/genética , Hibridación in Situ , Compresión Nerviosa , Vías Nerviosas/fisiología , Oligonucleótidos Antisentido , Nervio Óptico/metabolismo , Nervio Óptico/ultraestructura , Proteínas Proto-Oncogénicas c-jun/genética , Ratas , Ratas Endogámicas , Células Ganglionares de la Retina/citología , Factores de Transcripción/genética
12.
J Neurotrauma ; 16(2): 153-63, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10098960

RESUMEN

We have investigated time course and characteristics of retinal ganglion cell (RGC) death after partial optic nerve injury. In situ end labeling of DNA fragments with the terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuridine (dUTP)-biotin nick end labeling (TUNEL) method revealed the presence of apoptotic cells on as early as 5 days postcrush with a very high number of TUNEL-positive cells 1 week postinjury. At the ultrastructural level, features of apoptosis were clearly present in the ganglion cell layer at this time point. Moreover, TUNEL-positive cells could be identified as retinal ganglion cells by retrograde labeling with fluorogold. In addition, DNA laddering characteristic for apoptosis was found 1 week postinjury. A considerable number of TUNEL-labeled cells was still found after 2 weeks postinjury. Retinal whole mounts prepared at postlesion days 2-5, however, revealed that many cell bodies with ruptured membranes as evidenced by nucleosomal Sytox staining were present. These cells were also identified as retinal ganglion cells by retrograde labeling with fluorogold. Moreover, at this early stages of RGC degeneration necrotic cellular profiles could be detected by electron microscopic analysis. Thus, evidence is provided that necrosis and apoptosis follow a distinctly different time course after partial optic nerve injury.


Asunto(s)
Apoptosis , Lesiones Encefálicas/patología , Necrosis , Degeneración Nerviosa/fisiopatología , Enfermedades del Nervio Óptico/patología , Células Ganglionares de la Retina/patología , Animales , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Etiquetado Corte-Fin in Situ , Masculino , Ratas , Ratas Endogámicas , Factores de Tiempo
13.
Brain Res ; 889(1-2): 251-5, 2001 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-11166714

RESUMEN

Despite a massive degeneration of retinal ganglion cells (RGC) after optic nerve crush (ONC) in hooded rats only a minor increase in retinal glial fibrillary acidic protein (GFAP)-immunoreactivity was found in the inner retina. Interestingly, a combination of ONC with the administration of the proinflammatory agent lipopolysaccharide (LPS) but not LPS alone induces increased GFAP-immunoreactivity. In contrast albino rats showed elevated GFAP-immunoreactivity in response to both, LPS-administration and ONC with no further increase after a combination of both. These data demonstrate significant differences in retinal glia responsiveness between hooded and albino rats after optic nerve lesions.


Asunto(s)
Lipopolisacáridos/toxicidad , Neuroglía/patología , Traumatismos del Nervio Óptico/patología , Retina/patología , Animales , Western Blotting , Proteína Ácida Fibrilar de la Glía/metabolismo , Inmunohistoquímica , Masculino , Compresión Nerviosa , Neuroglía/metabolismo , Traumatismos del Nervio Óptico/metabolismo , Ratas , Ratas Sprague-Dawley , Ratas Wistar , Retina/metabolismo
14.
Exp Clin Endocrinol Diabetes ; 104(5): 365-9, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8957271

RESUMEN

UNLABELLED: There is no unequivocal data on the prevalence of Helicobacter pylori (Hp) and different types of gastritis in diabetic patients. The aim of this study was to define the prevalence of Hp infection, chronic active gastritis and reactive gastritis in diabetics and the effect of autonomic neuropathy (AN) as evaluated in four cardiovascular tests. Gastroscopy was performed on 139 patients with symptoms related to upper alimentary tract disorders--39 with diabetes mellitus, including 11 with insulin-dependent diabetes mellitus (IDDM) and 28 with non-insulin-dependent diabetes mellitus (NIDDM) and 100 patients without diabetes. The presence of Hp and gastritis was analysed in 3 biopsies. Hp infection was significantly less frequent (P < 0.001) in diabetics (30%, 12/39) than in non-diabetics (68%, 68/100). The prevalence of chronic active gastritis in diabetic patients was 41% (16/39), whereas among the controls it was 71% (71/100) (p < 0.01). In diabetics with AN Hp infection there was less frequent prevalence (29%, 5/17) than in diabetics without AN (35%, 5/14), (NS). Compared with non-diabetics Hp infection was less frequent in patients with diabetes and AN (p < 0.01), and in patients without AN (p < 0.05). In diabetics reactive gastritis was significantly more frequent (22%, 8/36) than in non-diabetics (3%, 3/100) (p < 0.01). Reactive gastritis is regarded as less sensitive to Hp infection. CONCLUSIONS: 1. Hp seems to play a minor role in the pathology of the upper alimentary tract in diabetes mellitus than in the general population. 2. The lower prevalence of Hp infection may result from AN and from a higher frequency of reactive gastritis.


Asunto(s)
Complicaciones de la Diabetes , Gastritis/complicaciones , Gastritis/microbiología , Infecciones por Helicobacter/complicaciones , Helicobacter pylori , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Gastritis/epidemiología , Gastroscopía , Infecciones por Helicobacter/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Prevalencia
15.
Neurol Neurochir Pol ; 12(2): 185-7, 1978.
Artículo en Polaco | MEDLINE | ID: mdl-673126

RESUMEN

A case of cavernous angioma of the medulla oblongata with clinical manifestations developing during the course of upper respiratory tract infection in a boy aged 16 years is described. In the first stage of the disease there were bulbar signs of gradually increasing intensity without changes in CSF. In the third week fatal haemorrhage to the medulla oblongata perforating into the cerebral ventricles and subarachnoid space occurred.


Asunto(s)
Neoplasias Encefálicas/patología , Hemangioma Cavernoso/patología , Bulbo Raquídeo , Adolescente , Hemorragia Cerebral , Ventrículos Cerebrales , Femenino , Humanos , Bulbo Raquídeo/patología
16.
Przegl Lek ; 56(5): 357-61, 1999.
Artículo en Polaco | MEDLINE | ID: mdl-10554573

RESUMEN

During past years a significant progress in improving and introducing personal insulin pumps into diabetic treatment has been observed. In the article indications of use the personal insulin pumps were presented, emphasized benefits resulting from this treatment modality.


Asunto(s)
Diabetes Mellitus Tipo 1/tratamiento farmacológico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Sistemas de Infusión de Insulina , Insulina/administración & dosificación , Humanos
17.
Przegl Lek ; 53(7): 540-3, 1996.
Artículo en Polaco | MEDLINE | ID: mdl-8975289

RESUMEN

UNLABELLED: There is very few data on the prevalence of reactive gastritis (RG) in diabetes mellitus (DM). The typical histological findings in RG are foveolar hyperplasia, oedema with apparent diminution in glands, telangiectasia of lamina propria, a paucity of inflammatory cells. RG has been connected so far with a long term use of non-steroidal anti-inflammatory drugs (NSAIDs) or bile reflux, which is particularly frequent after cholecystectomy. RG is regarded as less frequently associated with the Helicobacter pylori (Hp) infection. The aim of the study was to define: 1. The prevalence of RG in diabetics with dyspeptic symptoms as compared with the non-diabetic group. 2. The prevalence of Hp infection in RG as compared with chronic active gastritis (CAG) in DM. 3. The association of these types of gastritis with autonomic neuropathy (AN). STUDY DESIGN: Gastroscopy was performed in 152 patients with symptoms related to upper alimentary tract disorders-52 with DM (13 with IDDM and 39 with NIDDM) and 100 without DM. The presence of RG, CAG and Hp infection was analysed in 3 biopsies. AN was evaluated in 35 diabetics in 4 cardiovascular tests using ProSciCard. RESULTS: RG was significantly more frequent in DM than in control group (10/52, 19.2% vs. 3/100, 3%, respectively, p < 0.01). This difference was preserved after excluding all patients with NSAIDs use or being after cholecystectomy (8/36, 22.2% vs. 2/81, 2.5%, respectively, p < 0.001). Hp infection in diabetics with RG was significantly lower than diabetics with CAG (2/10, 20% vs. 16/23, 69.5%, respectively, p < 0.05). AN was more frequent in diabetics with RG than with CAG (7/10, 70% vs. 6/15, 40%, respectively, p < 0.001). Hp infection in diabetics with RG was significantly lower than diabetics with CAG (2/10, 20% vs. 16/23, 69.5%, respectively, p < 0.05). AN was more frequent in diabetics with RG than with CAG (7/10, 70% vs. 6/15, 40%, respectively), the difference was not significant with this sample size. CONCLUSIONS: 1. RG seems to be more frequent in DM than in general population. 2. Hp infection is less frequent in RG than in CAG in DM. 3. The higher prevalence of RG in DM may result from impaired motility and reflux of bile caused by AN.


Asunto(s)
Complicaciones de la Diabetes , Gastritis/epidemiología , Adolescente , Adulto , Anciano , Enfermedades del Sistema Nervioso Autónomo/complicaciones , Neuropatías Diabéticas/complicaciones , Gastritis/diagnóstico , Gastritis/etiología , Gastroscopía , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/epidemiología , Helicobacter pylori , Humanos , Persona de Mediana Edad , Prevalencia
18.
Eur Phys J C Part Fields ; 72(6): 2022, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-25814835

RESUMEN

The calibration and performance of the opposite-side flavour tagging algorithms used for the measurements of time-dependent asymmetries at the LHCb experiment are described. The algorithms have been developed using simulated events and optimized and calibrated with B+→J/ψK+, B0→J/ψK∗0 and B0→D∗-µ+νµ decay modes with 0.37 fb-1 of data collected in pp collisions at [Formula: see text] during the 2011 physics run. The opposite-side tagging power is determined in the B+→J/ψK+ channel to be (2.10±0.08±0.24) %, where the first uncertainty is statistical and the second is systematic.

19.
Eur Phys J C Part Fields ; 72(6): 2025, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-25814836

RESUMEN

The production of ϒ(1S), ϒ(2S) and ϒ(3S) mesons in proton-proton collisions at the centre-of-mass energy of [Formula: see text] is studied with the LHCb detector. The analysis is based on a data sample of 25 pb-1 collected at the Large Hadron Collider. The ϒ mesons are reconstructed in the decay mode ϒ→µ+µ- and the signal yields are extracted from a fit to the µ+µ- invariant mass distributions. The differential production cross-sections times dimuon branching fractions are measured as a function of the ϒ transverse momentum pT and rapidity y, over the range pT <15 GeV/c and 2.0

20.
Eur Phys J C Part Fields ; 72(8): 2100, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-25814845

RESUMEN

The differential cross-section for the inclusive production of ψ(2S) mesons in pp collisions at [Formula: see text] has been measured with the LHCb detector. The data sample corresponds to an integrated luminosity of 36 pb-1. The ψ(2S) mesons are reconstructed in the decay channels ψ(2S)→µ+µ- and ψ(2S)→J/ψπ+π-, with the J/ψ meson decaying into two muons. Results are presented both for promptly produced ψ(2S) mesons and for those originating from b-hadron decays. In the kinematic range pT(ψ(2S))≤16 GeV/c and 2

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