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1.
Phys Rev Lett ; 116(4): 041801, 2016 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-26871322

RESUMO

We report on measurements of the decays of B¯ mesons into the semileptonic final states B¯â†’D^(*)π^(+)π^(-)ℓ^(-)ν¯, where D^(*) represents a D or D^(*) meson and ℓ^(-) is an electron or a muon. These measurements are based on 471×10^(6) BB ¯ pairs recorded with the BABAR detector at the SLAC asymmetric B factory PEP-II. We determine the branching fraction ratios R_{π^{+}π^{-}}^{(*)}=B(B[over ¯]→D^{(*)}π^{+}π^{-}ℓ^{-}ν[over ¯])/B(B[over ¯]→D^{(*)}ℓ^{-}ν[over ¯]) using events in which the second B meson is fully reconstructed. We find R_{π^{+}π^{-}}=0.067±0.010±0.008 and R_{π^{+}π^{-}}^{*}=0.019±0.005±0.004, where the first uncertainty is statistical and the second is systematic. Based on these results and assuming isospin invariance, we estimate that B[over ¯]→D^{(*)}ππℓ^{-}ν[over ¯] decays, where π denotes either a π^{±} and π^{0} meson, account for up to half the difference between the measured inclusive semileptonic branching fraction to charm hadrons and the corresponding sum of previously measured exclusive branching fractions.

2.
Phys Rev Lett ; 114(17): 171801, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25978225

RESUMO

We present a search for a neutral, long-lived particle L that is produced in e+ e- collisions and decays at a significant distance from the e+ e- interaction point into various flavor combinations of two oppositely charged tracks. The analysis uses an e+ e- data sample with a luminosity of 489.1 fb(-1) collected by the BABAR detector at the ϒ(4S), ϒ(3S), and ϒ(2S) resonances and just below the ϒ(4S). Fitting the two-track mass distribution in search of a signal peak, we do not observe a significant signal, and set 90% confidence level upper limits on the product of the L production cross section, branching fraction, and reconstruction efficiency for six possible two-body L decay modes as a function of the L mass. The efficiency is given for each final state as a function of the mass, lifetime, and transverse momentum of the candidate, allowing application of the upper limits to any production model. In addition, upper limits are provided on the branching fraction B(B→XsL), where Xs is a strange hadronic system.

3.
Phys Rev Lett ; 114(8): 081801, 2015 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-25768754

RESUMO

We present a measurement of the asymmetry A_{CP} between same-sign inclusive dilepton samples ℓ^{+}ℓ^{+} and ℓ^{-}ℓ^{-} (ℓ=e, µ) from semileptonic B decays in ϒ(4S)→BB[over ¯] events, using the complete data set recorded by the BABAR experiment near the ϒ(4S) resonance, corresponding to 471×10^{6} BB[over ¯] pairs. The asymmetry A_{CP} allows comparison between the mixing probabilities P(B[over ¯]^{0}→B^{0}) and P(B^{0}→B[over ¯]^{0}), and therefore probes CP and T violation. The result, A_{CP}=[-3.9±3.5(stat)±1.9(syst)]×10^{-3}, is consistent with the standard model expectation.

4.
Phys Rev Lett ; 113(20): 201801, 2014 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-25432035

RESUMO

Dark sectors charged under a new Abelian interaction have recently received much attention in the context of dark matter models. These models introduce a light new mediator, the so-called dark photon (A^{'}), connecting the dark sector to the standard model. We present a search for a dark photon in the reaction e^{+}e^{-}→γA^{'}, A^{'}→e^{+}e^{-}, µ^{+}µ^{-} using 514 fb^{-1} of data collected with the BABAR detector. We observe no statistically significant deviations from the standard model predictions, and we set 90% confidence level upper limits on the mixing strength between the photon and dark photon at the level of 10^{-4}-10^{-3} for dark photon masses in the range 0.02-10.2 GeV. We further constrain the range of the parameter space favored by interpretations of the discrepancy between the calculated and measured anomalous magnetic moment of the muon.

5.
Phys Rev Lett ; 111(11): 111801, 2013 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-24074072

RESUMO

We measure the mass difference Δm0 between the D*(2010)+ and the D0 and the natural linewidth Γ of the transition D*(2010)+ → D0π+. The data were recorded with the BABAR detector at center-of-mass energies at and near the Υ(4S) resonance, and correspond to an integrated luminosity of approximately 477 fb(-1). The D0 is reconstructed in the decay modes D0 → K- π+ and D0 → K- π+ π- π+. For the decay mode D0 → K- π+ we obtain Γ = (83.4±1.7±1.5) keV and Δm0 = (145425.6±0.6±1.7) keV, [corrected] where the quoted errors are statistical and systematic, respectively. For the D0 → K- π+ π- π+ mode we obtain Γ = (83.2±1.5±2.6) keV and Δm0 = (145426.6±0.5±1.9) keV. [corrected] The combined measurements yield Γ = (83.3±1.2±1.4) keV and Δm0 = (145425.9±0.4±1.7) keV; the width is a factor of approximately 12 times more precise than the previous value, while the mass difference is a factor of approximately 6 times more precise.

6.
Phys Rev Lett ; 111(10): 101802, 2013 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-25166652

RESUMO

We present results of a search for CP violation in B0- B0 mixing with the BABAR detector. We select a sample of B0→D*- Xℓ+ ν decays with a partial reconstruction method and use kaon tagging to assess the flavor of the other B meson in the event. We determine the CP violating asymmetry ACP≡[N(B0B0)-N(B0B0)]/[N(B0B0)+N(B0B0)]=(0.06±0.17(-0.32)(+0.38))%, corresponding to ΔCP=1-|q/p|=(0.29±0.84(-1.61)(+1.88))×10(-3).

7.
Otolaryngol Clin North Am ; 34(1): 227-41, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11344075

RESUMO

Frontal headache is a common complaint associated with frontal sinus disease and is often the only complaint. It is also a common location for headache pain in association with other primary and secondary headache disorders. Therefore, the clinician needs to have a thorough understanding of the differential diagnosis of frontal headache pain. This article reviews the causes of frontal pain in association with nasal and sinus pathology and also discusses other headache disorders that can present with similar symptoms.


Assuntos
Sinusite Frontal/complicações , Sinusite Frontal/fisiopatologia , Cefaleia/etiologia , Adolescente , Diagnóstico Diferencial , Feminino , Sinusite Frontal/diagnóstico , Cefaleia/classificação , Cefaleia/diagnóstico , Humanos , Tomografia Computadorizada por Raios X
8.
Laryngoscope ; 111(1): 9-14, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11192906

RESUMO

OBJECTIVES/HYPOTHESIS: Two of the most common causes of olfactory loss include upper respiratory infection (URI) and nasal or sinus disease. The etiology of most URI-related losses is thought to be viral and, as yet, there is no available treatment. In contrast, nasal or sinus disease produces an obstructive or conductive loss that often responds dramatically to appropriate therapy. Therefore, the distinction is important but in many cases may be difficult because such patients often present with no other nasal symptoms, and routine physical findings may be nonspecific. The purpose of this report is to characterize those aspects of the history and physical examination that will help to substantiate the diagnosis of a conductive olfactory loss. STUDY DESIGN: A retrospective, nonrandomized study of consecutive patients presenting with a primary complaint of olfactory loss. METHODS: This study reviewed 428 patients seen at a university-based taste and smell clinic from July 1987 through December 1998. Of this total, 60 patients were determined to have a conductive olfactory loss. All patients were referred specifically because of a primary chemosensory complaint. The University of Pennsylvania Smell Identification Test (UPSIT; Sensonics, Inc., Haddon Heights, NJ) was administered in all cases. RESULTS: The most commonly diagnosed etiologies of olfactory loss were head injury (18%), upper respiratory infection (18%), and nasal or sinus disease (14%). Of the 60 patients with a conductive loss, only 30% complained of nasal obstruction, whereas 58% described a history of chronic sinusitis. Only 45% reported that their olfactory loss at times seemed to fluctuate in severity. Anterior rhinoscopy failed to diagnose pathology in 51% of cases, whereas nasal endoscopy missed the diagnosis in 9%. Systemic steroids elicited a temporary reversal of conductive olfactory loss in 83% of patients who received them, offering a useful diagnostic maneuver, whereas topical steroids did so in only 25%. CONCLUSIONS: The etiology for olfactory loss can in many cases be difficult to determine, but it is important to establish prognosis and to predict response to therapy. Diagnosis requires a thorough history, appropriate chemosensory testing, and a physical examination that should include nasal endoscopy. A trial of systemic steroids may serve to verify that the loss is indeed conductive.


Assuntos
Transtornos do Olfato/diagnóstico , Corticosteroides/administração & dosagem , Corticosteroides/uso terapêutico , Doença Crônica , Traumatismos Craniocerebrais/complicações , Traumatismos Craniocerebrais/diagnóstico , Endoscopia , Feminino , Humanos , Masculino , Anamnese , Pessoa de Meia-Idade , Obstrução Nasal/complicações , Obstrução Nasal/diagnóstico , Pólipos Nasais/complicações , Pólipos Nasais/diagnóstico , Doenças Nasais/complicações , Doenças Nasais/diagnóstico , Transtornos do Olfato/etiologia , Doenças dos Seios Paranasais/complicações , Doenças dos Seios Paranasais/diagnóstico , Planejamento de Assistência ao Paciente , Exame Físico , Prognóstico , Infecções Respiratórias/complicações , Infecções Respiratórias/diagnóstico , Estudos Retrospectivos , Rinite/complicações , Rinite/diagnóstico , Sinusite/complicações , Sinusite/diagnóstico , Olfato/fisiologia , Estatísticas não Paramétricas , Paladar/fisiologia
9.
Acta Cytol ; 44(6): 1073-6, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11127737

RESUMO

BACKGROUND: Fine needle aspiration (FNA) biopsy is reliably used to classify most conditions involving the salivary glands. It is useful for establishing, or at least suggesting, the diagnosis in unusual cases or narrowing the differential diagnosis. CASE: A 25-year-old male presented with a slowly enlarging mass of the left parotid. FNA biopsy of the parotid gland was performed, and a diagnosis of papillary-cystic variant of acinic cell carcinoma was suggested. The patient underwent incomplete resection of the lesion, which was interpreted as acinic cell carcinoma. CONCLUSION: Papillary-cystic variant of acinic cell carcinoma is rarely seen, especially in young people. FNA biopsy is a useful diagnostic procedure that can help diagnose this relatively uncommon type of salivary gland neoplasm and guide its management.


Assuntos
Carcinoma de Células Acinares/patologia , Neoplasias das Glândulas Salivares/patologia , Adulto , Biópsia por Agulha , Carcinoma Papilar/patologia , Cistadenocarcinoma/patologia , Humanos , Masculino
11.
Arch Otolaryngol Head Neck Surg ; 121(10): 1183-7, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7546588

RESUMO

OBJECTIVE: To determine the extent to which olfactory function can improve after loss induced by head trauma or a previous upper respiratory tract infection (URI) and the time for this improvement for more effective patient counseling. DESIGN: Patients initially evaluated at the University of Cincinnati (Ohio) Taste and Smell Center were reevaluated for olfactory loss with the University of Pennsylvania (Philadelphia) Smell Identification Test 1 to 5 years after initial testing. Changes in score on this test were used to indicate improvement in sensory function. Subjective information on olfactory ability and olfactory symptoms was also collected. SETTING: University-based tertiary care center. PATIENTS AND OTHER PARTICIPANTS: Forty-one patients with olfactory loss induced by head trauma (20) or previous URI (21). RESULTS: Seven (35%) of 20 patients with head trauma improved on the smell test by 4 points or more. Fourteen of 21 (67%) patients with a previous URI had improved scores of this magnitude or more. A statistically significant correlation was noted between the amounts of improvement and length of follow-up for URI patients. Thirteen of these patients also reported improved olfactory function. CONCLUSION: These findings for patients with head trauma are consistent with other reports of recovery of (or improvement in) olfactory function after trauma-induced loss. For patients with previous URI, these data indicate that improvement in olfactory function occurs, but the improvement may take several years.


Assuntos
Traumatismos Craniocerebrais/complicações , Transtornos do Olfato/etiologia , Infecções Respiratórias/complicações , Adulto , Aconselhamento , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Odorantes , Transtornos do Olfato/fisiopatologia , Remissão Espontânea , Reprodutibilidade dos Testes , Olfato/fisiologia
12.
Laryngoscope ; 105(9 Pt 1): 919-23, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7666725

RESUMO

Within the upper aerodigestive tract, histoplasmosis often mimics carcinoma, making prompt and accurate diagnosis imperative. More severe and potentially lethal infections with Histoplasma capsulatum are now being seen as the numbers of patients at the extremes of age, as well as those with compromised immune systems, increase. We reviewed the cases of 115 hospitalized patients with disseminated histoplasmosis. Of these, 9 patients were identified with otolaryngologic manifestations: 4 were infected with human immunodeficiency virus (HIV), 1 was diabetic, and 3 were renal transplant patients. Sites of involvement included the larynx (in 2 cases) and the oral cavity and oral pharynx (in 7 cases). Eight of the 9 patients had a positive biopsy result; the other, a positive culture. Treatment with amphotericin B was generally effective, while the use of newer azole anti-fungal agents were less effective. As the number of immunocompromised patients continues to increase in modern clinical practice, histoplasmosis will undoubtedly be encountered more frequently in the head and neck area.


Assuntos
Histoplasmose , Doenças da Laringe/microbiologia , Doenças Estomatognáticas/microbiologia , Anfotericina B/uso terapêutico , Infecções por HIV/complicações , Histoplasmose/diagnóstico , Histoplasmose/tratamento farmacológico , Humanos , Itraconazol/uso terapêutico , Doenças da Laringe/diagnóstico , Neoplasias Laríngeas/diagnóstico , Laringoscopia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Doenças Estomatognáticas/complicações , Doenças Estomatognáticas/tratamento farmacológico , Resultado do Tratamento
14.
New Horiz ; 1(2): 261-70, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-7522919

RESUMO

A frequently overlooked source of sepsis in the critical care patient is the paranasal sinuses. These patients are typically unable to communicate and, therefore, the usual findings of sinus infection, such as facial pain and complaints of purulent drainage, will be absent. Sepsis may be the first manifestation of such infection. Nasotracheal intubation is the most important predisposing factor to developing sinusitis in these patients. The clinician, therefore, must maintain a high index of suspicion in any patient with fever of unknown origin. Radiologic studies, including plain sinus radiographs, or preferably, a computed tomography scan, will usually show the presence of fluid or inflammation. Lavage of the maxillary sinus is helpful both to verify the presence of infection and to obtain culture material. These infections tend to be polymicrobial, and often display a predominance of Gram-negative organisms, particularly Pseudomonas aeruginosa. Treatment includes removal of all nasal tubes and institution of appropriate antibiotics, along with decongestant therapy. In some cases, surgical drainage will be necessary. For patients who are immunocompromised, or requiring intubation for > 7 days, the nasotracheal route is best avoided.


Assuntos
Infecção Hospitalar , Unidades de Terapia Intensiva , Sinusite , Antibacterianos/uso terapêutico , Causalidade , Terapia Combinada , Infecção Hospitalar/diagnóstico , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/etiologia , Infecção Hospitalar/terapia , Drenagem/instrumentação , Drenagem/métodos , Dor Facial/etiologia , Febre/etiologia , Humanos , Intubação Intratraqueal/efeitos adversos , Descongestionantes Nasais/uso terapêutico , Sinusite/diagnóstico , Sinusite/epidemiologia , Sinusite/etiologia , Sinusite/terapia , Tomografia Computadorizada por Raios X
16.
Otolaryngol Clin North Am ; 25(4): 817-35, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1470441

RESUMO

Chemosensory disorders have been receiving increasing clinical attention but remain a difficult diagnostic problem. With the development of several well-standardized testing methods, taste or smell loss can now be verified, and this has added to knowledge concerning the common causes of dysfunction. Diagnosis typically rests upon the history and physical examination, but, except in the case of obstructive nasal and sinus pathologic conditions, therapy usually remains elusive.


Assuntos
Transtornos do Olfato , Distúrbios do Paladar , Assistência Ambulatorial , Traumatismos Craniocerebrais/complicações , Humanos , Transtornos do Olfato/diagnóstico , Transtornos do Olfato/etiologia , Transtornos do Olfato/terapia , Prognóstico , Doenças Respiratórias/complicações , Células Receptoras Sensoriais/anatomia & histologia , Células Receptoras Sensoriais/fisiologia , Distúrbios do Paladar/diagnóstico , Distúrbios do Paladar/etiologia , Distúrbios do Paladar/terapia
18.
Arch Otolaryngol Head Neck Surg ; 118(7): 731-8, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1627295

RESUMO

Thirty-six mucosal specimens were obtained with a biopsy instrument from the upper nasal septum of 12 human autopsy cases before the en bloc removal of the entire olfactory area. Examination of these 36 specimens with transmission electron microscopy demonstrated olfactory epithelium in only 17. A significant negative correlation (r = -.728) was noted between the age of the subject and the probability of obtaining olfactory epithelium, supporting the idea that the olfactory mucosa is gradually replaced by respiratory epithelium with aging. Using the en bloc specimens, the distribution of olfactory epithelium was reconstructed from light microscopic examination of silver-stained sections. Multiple patches of respiratory epithelium were observed over the upper portion of the nasal septum and superior turbinates, ie, the presumptive olfactory area. On transmission electron microscopic examination, frequent respiratory metaplasia was also suggested. Within the area of respiratory metaplasia, supporting cell-like and microvillar cell-like structures often were found; these structures may be remnants of olfactory epithelium. The sampling of olfactory tissue with a biopsy procedure is hampered by the irregular and patchy distribution of olfactory epithelium. The invasion of respiratory epithelial patches into the olfactory mucosa seems to be characteristic of the human olfactory epithelium and may increase as a function of age. Thus, conclusions about the structure of the olfactory mucosa in an individual patient must be based on several tissue samples.


Assuntos
Envelhecimento/fisiologia , Mucosa Olfatória/citologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Autopsia , Células Epiteliais , Humanos , Metaplasia , Microscopia Eletrônica , Pessoa de Meia-Idade , Sistema Respiratório/citologia
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