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1.
Phys Rev Lett ; 126(16): 161801, 2021 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-33961476

RESUMEN

We present a measurement of R_{K^{*}}, the branching fraction ratio B(B→K^{*}µ^{+}µ^{-})/B(B→K^{*}e^{+}e^{-}), for both charged and neutral B mesons. The ratio for the charged case R_{K^{*+}} is the first measurement ever performed. In addition, we report absolute branching fractions for the individual modes in bins of the squared dilepton invariant mass q^{2}. The analysis is based on a data sample of 711 fb^{-1}, containing 772×10^{6} BB[over ¯] events, recorded at the ϒ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. The obtained results are consistent with standard model expectations.

2.
Phys Rev Lett ; 122(8): 082001, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30932568

RESUMEN

We present the first measurements of absolute branching fractions of Ξ_{c}^{0} decays into Ξ^{-}π^{+}, ΛK^{-}π^{+}, and pK^{-}K^{-}π^{+} final states. The measurements are made using a dataset comprising (772±11)×10^{6} BB[over ¯] pairs collected at the ϒ(4S) resonance with the Belle detector at the KEKB e^{+}e^{-} collider. We first measure the absolute branching fraction for B^{-}→Λ[over ¯]_{c}^{-}Ξ_{c}^{0} using a missing-mass technique; the result is B(B^{-}→Λ[over ¯]_{c}^{-}Ξ_{c}^{0})=(9.51±2.10±0.88)×10^{-4}. We subsequently measure the product branching fractions B(B^{-}→Λ[over ¯]_{c}^{-}Ξ_{c}^{0})B(Ξ_{c}^{0}→Ξ^{-}π^{+}), B(B^{-}→Λ[over ¯]_{c}^{-}Ξ_{c}^{0})B(Ξ_{c}^{0}→ΛK^{-}π^{+}), and B(B^{-}→Λ[over ¯]_{c}^{-}Ξ_{c}^{0})B(Ξ_{c}^{0}→pK^{-}K^{-}π^{+}) with improved precision. Dividing these product branching fractions by the result for B^{-}→Λ[over ¯]_{c}^{-}Ξ_{c}^{0} yields the following branching fractions: B(Ξ_{c}^{0}→Ξ^{-}π^{+})=(1.80±0.50±0.14)%, B(Ξ_{c}^{0}→ΛK^{-}π^{+})=(1.17±0.37±0.09)%, and B(Ξ_{c}^{0}→pK^{-}K^{-}π^{+})=(0.58±0.23±0.05)%. For the above branching fractions, the first uncertainties are statistical and the second are systematic. Our result for B(Ξ_{c}^{0}→Ξ^{-}π^{+}) can be combined with Ξ_{c}^{0} branching fractions measured relative to Ξ_{c}^{0}→Ξ^{-}π^{+} to yield other absolute Ξ_{c}^{0} branching fractions.

3.
Phys Rev Lett ; 121(3): 031801, 2018 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-30085771

RESUMEN

We report the results of a search for the rare, purely leptonic decay B^{-}→µ^{-}ν[over ¯]_{µ} performed with a 711 fb^{-1} data sample that contains 772×10^{6} BB[over ¯] pairs, collected near the ϒ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. The signal events are selected based on the presence of a high momentum muon and the topology of the rest of the event showing properties of a generic B-meson decay, as well as the missing energy and momentum being consistent with the hypothesis of a neutrino from the signal decay. We find a 2.4 standard deviation excess above background including systematic uncertainties, which corresponds to a branching fraction of B(B^{-}→µ^{-}ν[over ¯]_{µ})=(6.46±2.22±1.60)×10^{-7} or a frequentist 90% confidence level interval on the B^{-}→µ^{-}ν[over ¯]_{µ} branching fraction of [2.9,10.7]×10^{-7}.

4.
Prostate Cancer Prostatic Dis ; 20(2): 210-215, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28094251

RESUMEN

BACKGROUND: In the United States, disease-specific mortality from prostate cancer (PC) is highest among black men. While the introduction of widespread PSA testing has been associated with a downward stage migration, whether this trend continues in the late PSA era and for black men is unknown. The objective of our study was to evaluate current PC stage migration patterns in the United States by race. METHODS: The Surveillance, Epidemiology and End Results (SEER) registry was queried to obtain all cases of PC reported between 2000 and 2013. Year of diagnosis was categorized into 2000-2003, 2004-2007, 2008-2010 and 2011-2013. Predictors of distant stage PC at diagnosis were determined using logistic regression adjusted for year of diagnosis, age at diagnosis, SEER region and race. RESULTS: A total of 791 184 PC cases were identified. The cohort comprised 78.9% (n=594 920) white and 14.1% (n=106 133) black men. The stage at diagnosis was 83.3% localized, 12.0% regional and 4.7% distant. Age-adjusted incidence demonstrated a steady decline for black men in all time groups while white men had a stable incidence of distant disease between 2000 and 2013. In univariate analysis, black men in the 2004-2007 (OR 0.86 (0.81-0.93)) and 2008-2010 cohorts (OR 0.85 (0.79-0.91)) were less likely to be diagnosed with metastatic PC as compared with the 2000-2003 baseline cohort. In multivariate analysis, the 2004-2007 black cohort was less likely to be diagnosed with distant PC (OR 0.90 (0.84-0.97)). This trend was not observed in white men who in multivariate analysis had an increased risk of distant PC in the 2004-2007 (OR 1.08 (1.04-1.11)), 2008-2010 (OR 1.22 (1.18-1.27)) and 2011-2013 (OR 1.65 (1.59-1.71)) groups. CONCLUSIONS: PC downward stage migration continues in black men but not in white men. Discontinuation of PSA-based screening for PC could disproportionately affect black men.


Asunto(s)
Antígeno Prostático Específico/genética , Neoplasias de la Próstata/epidemiología , Neoplasias de la Próstata/genética , Negro o Afroamericano/genética , Anciano , Estudios de Cohortes , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Neoplasias de la Próstata/patología , Programa de VERF , Estados Unidos/epidemiología , Población Blanca/genética
5.
Phys Rev Lett ; 117(14): 142001, 2016 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-27740802

RESUMEN

Using data collected with the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider, we measure the energy dependence of the e^{+}e^{-}→h_{b}(nP)π^{+}π^{-} (n=1, 2) cross sections from thresholds up to 11.02 GeV. We find clear ϒ(10860) and ϒ(11020) peaks with little or no continuum contribution. We study the resonant substructure of the ϒ(11020)→h_{b}(nP)π^{+}π^{-} transitions and find evidence that they proceed entirely via the intermediate isovector states Z_{b}(10610) and Z_{b}(10650). The relative fraction of these states is loosely constrained by the current data: The hypothesis that only Z_{b}(10610) is produced is excluded at the level of 3.3 standard deviations, while the hypothesis that only Z_{b}(10650) is produced is not excluded at a significant level.

6.
Phys Rev Lett ; 117(1): 011801, 2016 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-27419562

RESUMEN

We report the first observation of the decay Λ_{c}^{+}→pK^{+}π^{-} using a 980 fb^{-1} data sample collected by the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. This is the first observation of a doubly Cabibbo-suppressed decay of a charmed baryon. We measure the branching ratio of this decay with respect to its Cabibbo-favored counterpart to be B(Λ_{c}^{+}→pK^{+}π^{-})/B(Λ_{c}^{+}→pK^{-}π^{+})=(2.35±0.27±0.21)×10^{-3}, where the uncertainties are statistical and systematic, respectively.

7.
Phys Rev Lett ; 116(16): 161801, 2016 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-27152790

RESUMEN

We measure the decay B_{s}^{0}→K^{0}K[over ¯]^{0} using data collected at the ϒ(5S) resonance with the Belle detector at the KEKB e^{+}e^{-} collider. The data sample used corresponds to an integrated luminosity of 121.4 fb^{-1}. We measure a branching fraction B(B_{s}^{0}→K^{0}K[over ¯]^{0})=[19.6_{-5.1}^{+5.8}(stat)±1.0(syst)±2.0(N_{B_{s}^{0}B[over ¯]_{s}^{0}})]×10^{-6} with a significance of 5.1 standard deviations. This measurement constitutes the first observation of this decay.

8.
Phys Rev Lett ; 115(22): 221803, 2015 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-26650291

RESUMEN

We report the first observation of the decays B^{0}→pΛ[over ¯]D^{(*)-}. The data sample of 711 fb^{-1} used in this analysis corresponds to 772×10^{6} BB[over ¯] pairs, collected at the ϒ(4S) resonance by the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. We observe 19.8σ and 10.8σ excesses of events for the two decay modes and measure the branching fractions of B^{0}→pΛ[over ¯]D^{-} and B^{0}→pΛ[over ¯]D^{*-} to be (25.1±2.6±3.5)×10^{-6} and (33.6±6.3±4.4)×10^{-6}, respectively, where the first uncertainties are statistical and the second are systematic. These results are not compatible with the predictions based on the generalized factorization approach. In addition, a threshold enhancement in the dibaryon (pΛ[over ¯]) system is observed, consistent with that observed in similar B decays.

9.
Aliment Pharmacol Ther ; 41(9): 821-34, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25752753

RESUMEN

BACKGROUND: Many therapeutic drugs are used by patients with inflammatory bowel disease, often around the time of conception. The pregnancy outcomes of males and females exposed to these therapeutics needs to be examined and this information is necessary to counsel patients appropriately. AIM: To review the literature describing male infertility and inflammatory bowel disease to educate practitioners of the impact of inflammatory bowel disease on male reproduction and the impact of therapeutics on pregnancy outcomes. METHODS: We performed a PubMed search using the search terms 'male infertility,' 'Crohn's disease,' 'inflammatory bowel disease,' 'ulcerative colitis,' 'ciprofloxacin AND infertility,' 'metronidazole AND infertility,' 'sulfasalazine AND infertility,' 'azathioprine AND infertility,' 'methotrexate AND infertility,' 'ciclosporin AND infertility,' 'corticosteroids AND infertility,' 'infliximab AND male fertility,' 'infliximab AND infertility,' 'infliximab AND foetus,' 'infliximab AND paternal exposure' and 'infliximab AND sperm.' References from selected papers were reviewed and used if relevant. RESULTS: Over half of male patients with IBD have some degree of infertility, compared to 8-17% of the general population. Semen parameters including total count, motility and morphology may be adversely affected by therapeutics. IBD medications in males do not increase foetal risk with the possible exception of azathioprine and mercaptopurine; however, increased foetal risk is seen in other drugs if taken by female patients. CONCLUSIONS: It is recognised that male infertility is often impacted with therapeutic drugs used to treat inflammatory bowel disease; however, the effects of the paternal drug exposure at the time of conception and exposure in utero should be considered to counsel patients appropriately.


Asunto(s)
Colitis Ulcerosa/tratamiento farmacológico , Enfermedad de Crohn/tratamiento farmacológico , Inmunosupresores/uso terapéutico , Colitis Ulcerosa/fisiopatología , Enfermedad de Crohn/fisiopatología , Femenino , Humanos , Inmunosupresores/efectos adversos , Infertilidad Masculina/etiología , Masculino , Embarazo , Resultado del Embarazo
10.
Gene Ther ; 20(4): 425-34, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22809998

RESUMEN

Retinitis Pigmentosa (RP) is the leading cause of inherited blindness in the developed world, affecting approximately 1 in 3000 individuals. Although there is currently no cure for RP, the genetic pathology has been well established. In this study, we developed a novel mouse model of RP (huRhoP347S) expressing a pathogenic human rhodopsin gene with a Pro347Ser (P347S) mutation on a rhodopsin knockout background. These mice undergo severe retinal degeneration at 1 month of age. In contrast to prior studies, this model was administered a gene therapy treatment at 19 days postnata. We evaluated several self-complementary adeno-associated virus (AAV) serotypes for photoreceptor tropism, including scAAV2/2, scAAV2/5, scAAV2/6.2 and scAAV2/9, and found that scAAV2/9 transduced photoreceptors with greater efficiency and expression than other vectors. We engineered an scAAV2/9 vector to contain a microRNA sequence specifically targeting the human rhodopsin gene and demonstrated its ability to silence rhodopsin by 60.2±8.2% in vitro. In addition, we constructed an scAAV2/9 vector to contain a replacement 'codon-modified' rhodopsin transgene (RhoR2) that was resistant to degradation by the microRNA. We found that delivery of the RhoR2 by scAAV2/9 is capable of restoring vision to rhodopsin knockout mice, and rescuing our novel transgenic huRhoP347S mouse model of dominant RP. Average a-wave responses of RhoR2-injected eyes were 1.8-fold higher than those of control-injected eyes. We found that delivery of the microRNA and replacement rhodopsin in a 1:2 ratio produced an average electroretinography (ERG) a-wave response of 17.4±2.9 compared to 6.5±2.8 µV for eyes injected with negative control virus.


Asunto(s)
Modelos Animales de Enfermedad , Terapia Genética , Ratones/genética , Retinitis Pigmentosa/terapia , Animales , Dependovirus/genética , Silenciador del Gen , MicroARNs/metabolismo , Mutación Missense , Células Fotorreceptoras de Vertebrados/metabolismo , Retinitis Pigmentosa/genética , Retinitis Pigmentosa/patología , Rodopsina/genética , Rodopsina/metabolismo , Transgenes
11.
IEEE Trans Haptics ; 5(2): 131-8, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-26964069

RESUMEN

Minimally invasive surgery uses optical cameras and special surgical tools in order to operate from an environment one step removed from the body cavity of interest to the surgeon. It has been suggested that constraints posed by this arrangement, in particular the lack of direct haptic feedback to the surgeon, may affect the surgeon's ability to identify tissues and accurately maneuver inside the body cavity. In the present study, the ability of laypeople to detect artificial tumors of various hardness values embedded in silicone gels was assessed in a simulated MIS environment. Participants explored the gels under three conditions all with remote viewing; using the unrestricted bare finger, using a stick-like surgical tool also unrestricted, and using the surgical tool restricted by its insertion through an operating port as in MIS. Participants were significantly more accurate and more efficient at tumor detection with the finger as compared to the other methods of exploration, and they were also better at detecting harder tumors as compared to softer ones. The potential implications of these results for the role of haptic perception in minimally invasive surgery are discussed.

12.
Psychol Med ; 41(6): 1253-61, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20860867

RESUMEN

BACKGROUND: Cognitive rehabilitation has emerged as an effective treatment for addressing cognitive impairments and functional disability in schizophrenia; however, the degree to which changes in various social and non-social cognitive processes translate into improved functioning during treatment remains unclear. This research sought to identify the neurocognitive and social-cognitive mechanisms of functional improvement during a 2-year trial of cognitive enhancement therapy (CET) for early-course schizophrenia. METHOD: Patients in the early course of schizophrenia were randomly assigned to CET (n=31) or an enriched supportive therapy control (n=27) and treated for up to 2 years. A comprehensive neurocognitive assessment battery and the Mayer-Salovey-Caruso Emotional Intelligence Test (MSCEIT) were completed annually, along with measures of functioning. Mediator analyses using mixed-effects growth models were conducted to examine the effects of neurocognitive and social-cognitive improvement on functional change. RESULTS: Improvements over 2 years in neurocognition and the emotion management branch of the MSCEIT were found to be significantly related to improved functional outcome in early-course schizophrenia patients. Neurocognitive improvement, primarily in executive functioning, and social-cognitive change in emotion management also mediated the robust effects of CET on functioning. CONCLUSIONS: Improvements in neurocognition and social cognition that result from cognitive rehabilitation are both significant mediators of functional improvement in early-course schizophrenia. Cognitive rehabilitation programs for schizophrenia may need to target deficits in both social and non-social cognition to achieve an optimal functional response.


Asunto(s)
Trastornos del Conocimiento/psicología , Trastornos del Conocimiento/rehabilitación , Terapia Cognitivo-Conductual/métodos , Trastornos Psicóticos/psicología , Trastornos Psicóticos/rehabilitación , Esquizofrenia/rehabilitación , Psicología del Esquizofrénico , Adulto , Trastornos del Conocimiento/diagnóstico , Inteligencia Emocional , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas/estadística & datos numéricos , Psicometría/estadística & datos numéricos , Trastornos Psicóticos/diagnóstico , Reproducibilidad de los Resultados , Esquizofrenia/diagnóstico , Adulto Joven
17.
J Shoulder Elbow Surg ; 10(4): 321-6, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11517361

RESUMEN

Variable outcomes in the prosthetic reconstruction of 4-part humerus fractures often can be attributed to inconsistent and nonanatomic tuberosity placement. To compare the effects of anatomic (anterior fin) versus nonanatomic (lateral fin) tuberosity placement, we developed a dynamic cadaver model for shoulder motion. With the use of a robotically driven, computer-controlled articulator, we tested external rotation torque in 5 fresh human shoulders. After evaluation of the intact shoulders, we experimentally induced 4-part humerus fractures in the specimens. These were then repaired by hemiarthroplasty, with the use of standard techniques to secure the greater and lesser tuberosities in either anatomic or nonanatomic positions; order was randomized. Nonanatomic tuberosity reconstruction led to significant impairment in external rotation kinematics and an 8-fold increase in torque requirements (P =.001). In contrast, anatomic reconstruction produced results indistinguishable from normal shoulder controls. This study underscores the importance of rotational alignment of tuberosities during reconstruction. Failure to properly position tuberosity fragments in the horizontal plane may result in insurmountable postoperative motion restriction.


Asunto(s)
Artroplastia de Reemplazo/métodos , Fracturas del Húmero/cirugía , Implantación de Prótesis/métodos , Articulación del Hombro/fisiología , Adulto , Anciano , Fenómenos Biomecánicos , Cadáver , Femenino , Fijación de Fractura/métodos , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Rango del Movimiento Articular , Torque
18.
Gastroenterol Clin North Am ; 30(2): 445-73, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11432300

RESUMEN

The ischemic bowel diseases are a heterogeneous group of disorders usually seen in elderly individuals. They represent ischemic damage to different portions [figure: see text] of the bowel and produce a variety of clinical syndromes and outcomes. Colonic ischemia is the commonest of these disorders and has a favorable prognosis in most cases. In contrast, acute mesenteric ischemia, most commonly caused by a superior mesenteric artery embolus, is a disease with a poor prognosis. Acute mesenteric ischemia secondary to nonocclusive mesenteric ischemia usually is a [figure: see text] catastrophic complication of other severe medical illnesses, most notably atherosclerosis. Proper diagnosis and management of patients with ischemic bowel disease requires vigilance on the part of the physician and a willingness to embark on an aggressive plan of diagnosis and management in the appropriate setting.


Asunto(s)
Isquemia/etiología , Circulación Esplácnica , Factores de Edad , Anciano , Anciano de 80 o más Años , Algoritmos , Arteriosclerosis , Colon/irrigación sanguínea , Humanos , Isquemia/diagnóstico , Isquemia/terapia , Oclusión Vascular Mesentérica/diagnóstico por imagen , Oclusión Vascular Mesentérica/etiología , Oclusión Vascular Mesentérica/terapia , Venas Mesentéricas , Radiografía , Trombosis/etiología
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