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1.
Neurologia ; 31(5): 305-10, 2016 Jun.
Artículo en Inglés, Español | MEDLINE | ID: mdl-25976938

RESUMEN

INTRODUCTION: Transient headache and neurological deficits with cerebrospinal fluid lymphocytosis (HaNDL) is characterised by migraine-like headache episodes accompanied by neurological deficits consisting of motor, sensory, or aphasic symptoms. Electroencephalogram (EEG) and single photon emission computed tomography (SPECT) may show focal abnormalities that correspond to the neurological deficits. We aim to evaluate the correlation between focal deficit topography and EEG or SPECT abnormalities in 5 new cases. PATIENTS: We retrospectively reviewed patients attended in a tertiary hospital (January 2010-May 2014) and identified 5 patients (3 men, 2 women) with a mean age of 30.6 ± 7.7 (21-39) years. They presented 3.4 ± 2.6 episodes of headache (range, 2-8) of moderate to severe intensity and transient neurological deficits over a maximum of 5 weeks. Pleocytosis was detected in CSF in all cases (70 to 312 cells/mm3, 96.5-100% lymphocytes) with negative results from aetiological studies. RESULTS: At least one EEG was performed in 4 patients and SPECT in 3 patients. Patient 1: 8 episodes; 4 left hemisphere, 3 right hemisphere, and 1 brainstem; 2 EEGs showing left temporal and bilateral temporal slowing; normal SPECT. Patient 2: 2 episodes, left hemisphere and right hemisphere; SPECT showed decreased left temporal blood flow. Patient 3: 3 left hemisphere deficits; EEG with bilateral frontal and temporal slowing. Patient 4: 2 episodes with right parieto-occipital topography and right frontal slowing in EEG. Patient 5: 2 episodes, right hemisphere and left hemisphere, EEG with right temporal slowing; normal SPECT. CONCLUSION: The neurological deficits accompanying headache in HaNDL demonstrate marked clinical heterogeneity. SPECT abnormalities and most of all EEG abnormalities were not uncommon in our series and they did not always correlate to the topography of focal déficits.


Asunto(s)
Electroencefalografía/métodos , Linfocitosis/complicaciones , Trastornos Migrañosos/diagnóstico , Enfermedades del Sistema Nervioso/diagnóstico , Tomografía Computarizada de Emisión de Fotón Único/métodos , Adulto , Femenino , Humanos , Leucocitosis/líquido cefalorraquídeo , Linfocitosis/líquido cefalorraquídeo , Masculino , Trastornos Migrañosos/líquido cefalorraquídeo , Trastornos Migrañosos/diagnóstico por imagen , Trastornos Migrañosos/etiología , Estudios Retrospectivos , España , Síndrome
2.
Pathobiology ; 77(1): 38-45, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20185966

RESUMEN

OBJECTIVE: The Her2/neu status is of great clinical value in breast tumor patients. Fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) techniques are the test of choice for many practicing pathologies. The main objective of this retrospective study was to investigate the relationship between Her2/neu breast cancer amplification and overexpression (DNA, mRNA and protein). METHODS: To accomplish this goal, we evaluated Her2/neu mRNA expression by real-time quantitative RT-PCR, gene amplification by FISH and protein expression by IHC. RESULTS: An excellent correlation between FISH and IHC Her2/neu results was observed, confirming that protein levels were directly related to DNA amplification. Polysomy 17 was frequently found in tumors showing Her2/neu overexpression. However, we did not find any statistically significant correlation among DNA, mRNA and protein levels, suggesting that Her2/neu could be post-transcriptionally regulated. CONCLUSIONS: There was a highagreement between Her2/neu gene amplification and protein overexpression but not mRNA expression levels. Nevertheless, IHC3+ and FISH-positive tumors indicated higher expression levels of Her2/neu mRNA by RT-PCR than those observed in IHC and FISH-negative tumors. These findings question the relevance of quantitative RT-PCR in routine assessment of Her2/neu overexpression in human breast cancer in the clinical laboratory setting.


Asunto(s)
Neoplasias de la Mama/genética , Genes erbB-2 , Receptor ErbB-2/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Femenino , Humanos , Inmunohistoquímica , Hibridación Fluorescente in Situ/métodos , ARN Mensajero/análisis , Receptor ErbB-2/metabolismo , Estudios Retrospectivos
3.
Artículo en Inglés, Español | MEDLINE | ID: mdl-31776063

RESUMEN

Colorectal cancer is the third most frequent cancer worldwide. Although its incidence is increasing, mainly in those aged under50, mortality has decreased by 50% in the more developed countries, principally due to the adoption of new practices in prevention, diagnosis and treatment. In particular, the various diagnostic imaging modalities allow improved therapeutic decision-making, evaluation of the response and early detection of recurrence. The aim of this paper is to review the available scientific evidence on the value of positron emission tomography with 18F-FDG (18F-FDG PET/CT) in the colorectal cancer, with special emphasis on the indications of the guidelines and recommendations of the main international scientific associations regarding this imaging technique.


Asunto(s)
Neoplasias del Colon/diagnóstico por imagen , Fluorodesoxiglucosa F18 , Tomografía Computarizada por Tomografía de Emisión de Positrones , Radiofármacos , Neoplasias del Recto/diagnóstico por imagen , Neoplasias del Colon/patología , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/cirugía , Recurrencia Local de Neoplasia/diagnóstico por imagen , Estadificación de Neoplasias/métodos , Guías de Práctica Clínica como Asunto , Neoplasias del Recto/patología
4.
Clin Obes ; 8(1): 50-54, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29110411

RESUMEN

New-onset benign anal disorders (NBADs) represent a potential complication following bariatric surgery, although their incidence in this population is not well studied. The preoperative characteristics, weight loss, bowel habits and NBADs data of 196 patients with bariatric surgery were collected by telephone interviews and medical records review and evaluated retrospectively. Ninety-nine patients had undergone gastric bypass (GBP) and 97 had a modified biliopancreatic diversion (MBPD). Fifty-nine patients were excluded. The mean follow-up of the remaining 137 patients was 87.8 months, and 51 of them (37.2%) developed NBADs. Haemorrhoids were the most common diagnosis and 27.5% of the patients that developed NBADs were treated surgically. Patients who developed NBADs had a longer follow-up time (92.5 vs. 85.1 months, P = 0.003), and those with an abnormal bowel habit (diarrhoea or constipation) had a higher percentage of NBADs (54.5 vs. 28.3%, P = 0.003). NBADs were more frequent after MBPD (52.9%) than after GBP (21.7%) (P < 0.001). Multivariate analysis found that only an abnormal bowel habit was associated with NBADs, with an odds ratio of 3.2 (95% CI: 1.5-6.9, P = 0.003). As NBADs are a common complication after bariatric surgery, further studies should be performed to find the reasons for these complications.


Asunto(s)
Enfermedades del Ano/epidemiología , Cirugía Bariátrica/efectos adversos , Obesidad/cirugía , Enfermedades del Ano/diagnóstico , Enfermedades del Ano/fisiopatología , Enfermedades del Ano/terapia , Humanos , Incidencia , Obesidad/epidemiología , Estudios Retrospectivos , Factores de Riesgo , España/epidemiología , Factores de Tiempo , Resultado del Tratamiento
5.
Endocr Relat Cancer ; 14(3): 645-54, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17914095

RESUMEN

Testosterone is essential for the growth and function of the luminal prostate cells, but it is also critical for the development of prostate cancer, which in the majority of the cases derives from luminal cells. Cytochrome P450 3A (CYP3A) enzymes hydroxylate testosterone and dehydroepiandrosterone to less active metabolites, which might be the basis for the association between CYP3A polymorphisms and prostate cancer. However, it is unknown whether the CYP3A enzymes are expressed at relevant levels in the prostate and which polymorphisms could affect this tissue-specific CYP3A activity. Thus, we measured CYP3A4, CYP3A5, CYP3A7, and CYP3A43 mRNA in 14 benign prostatic hyperplasias and ten matched non-tumoral/tumoral prostate samples. We found that CYP3A5 mRNA in non-tumoral prostate tissue was 10% of the average amount of liver samples, whereas the expression of the other CYP3A genes was much lower. Similarly to liver, CYP3A5*3 polymorphism decreased CYP3A5 mRNA content 13-fold. CYP3A5 protein was detected in non-tumoral prostate microsomes by western blot, and immunohistochemistry (IHC) localized CYP3A5 exclusively in the basolateral prostate cells. In contrast to the normal tissue, IHC and RT-PCR showed that tumoral tissue lacked CYP3A5 expression. In conclusion, prostate basolateral cells express high levels of CYP3A5 which dramatically decrease in tumoral tissue. This finding supports an endogenous function of CYP3A5 related to the metabolism of intra-prostatic androgens and cell growth, and that polymorphisms affecting CYP3A5 activity may result in altered prostate cancer risk and aggressiveness.


Asunto(s)
Carcinoma/genética , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Próstata/metabolismo , Neoplasias de la Próstata/genética , Anciano , Anciano de 80 o más Años , Carcinoma/metabolismo , Carcinoma/patología , Citocromo P-450 CYP3A , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Polimorfismo Genético , Hiperplasia Prostática/genética , Hiperplasia Prostática/metabolismo , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología
6.
Rev Esp Med Nucl Imagen Mol ; 36(5): 312-321, 2017.
Artículo en Inglés, Español | MEDLINE | ID: mdl-28483374

RESUMEN

The aim of this work was to review the current recommendations for staging and response assessment of patients with Hodgkin lymphoma (HL) and non-Hodgkin lymphoma (NHL) in routine clinical practice after chemotherapy and/or stem cell transplantation. A five-point scale (5-PS) from the First International Workshop on PET in Lymphoma in Deauville, France, in 2009, was recommended as the standard tool to score imaging to assess treatment response in patients with lymphoma using 18F-Fluorodeoxyglucose (FDG) PET/CT. Following the recommendations of the 11th and 12th International Conferences on Malignant Lymphoma held in Lugano (Switzerland), in 2011 and 2013, respectively, a consensus (the so-called Lugano Classification) was reached regarding the use of PET/CT for staging and response assessment in FDG-avid lymphomas. As a result, 18F-FDG PET/CT was formally incorporated into standard staging for FDG-avid lymphomas. A bone marrow biopsy is no longer indicated for the routine staging of HL and most diffuse large B-cell lymphomas. PET/CT will be used to assess response in FDG-avid histologies using the 5-point scale. The recent introduction of biological agents with immune mechanisms requires flexibility in interpretations of the Lugano criteria due to tumour flare or a pseudo-progression effect produced by these agents. Provisional criteria have been proposed (Lymphoma Response to Immunomodulatory Therapy Criteria) with the introduction of the term 'Indeterminate Response' in order to identify this phenomenon until confirmed as flare/pseudoprogression or true progression. All these recommendations will improve evaluations of patients with lymphoma, and allow comparison of results from clinical practice and trials.


Asunto(s)
Fluorodesoxiglucosa F18 , Enfermedad de Hodgkin/diagnóstico por imagen , Linfoma no Hodgkin/diagnóstico por imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones , Radiofármacos , Enfermedad de Hodgkin/terapia , Humanos , Linfoma no Hodgkin/terapia , Guías de Práctica Clínica como Asunto
7.
Rev Esp Med Nucl Imagen Mol ; 35(6): 351-357, 2016.
Artículo en Inglés, Español | MEDLINE | ID: mdl-27132216

RESUMEN

AIM: To evaluate the value of 99mTc-MIBI double-phase scintigraphy (DPS) and early SPECT/CT in the pre-surgical assessment of patients with primary hyperparathyroidism (PHPT). Also, to calculate the correlation between uptake and some biological parameters. MATERIAL AND METHODS: Forty patients with PHPT were included: 37 solitary adenomas, 1 hyperplasia, and 2 double adenomas. Fifteen patients had ectopic glands. DPS and early SPECT/CT were acquired in all patients. Ultrasound was performed in 31/40. All patients underwent surgery, intra-operative iPTH measurements, and histopathological examinations. Qualitative DPS uptake was assessed and correlated to pre-surgical calcium, iPTH levels, gland weight, and maximum diameter. RESULTS: In the planar study, there were 23 positive cases, 8 doubtful, and 9 negatives. With the SPECT/CT, 8/9 negatives cases were located. All doubtful cases were confirmed as positives. Gland location improved in 16 cases (12 ectopic). DPS+SPECT/CT failed to detect a solitary adenoma and at least one gland in three cases of multiglandular disease (MGD). The sensitivity by patient was: DPS 72.5%, DPS+SPECT/CT 90%, and ultrasound 42%. Ultrasound and scintigraphy (DPS+SPECT/CT) were concordant in 16/31 patients. For the rest of them, scintigraphy proved correct in 14/15, and both techniques failed in one case. There was a significant correlation between level of uptake and iPTH level, gland weight, and maximum diameter. CONCLUSION: Early SPECT/CT improves sensitivity and the locating of parathyroid pathological glands and increases diagnostic confidence. iPTH level, glandular size, and weight are related to the qualitative assessment of 99mTc-MIBI uptake in early DPS.


Asunto(s)
Hiperparatiroidismo Primario/diagnóstico por imagen , Cintigrafía , Radiofármacos , Tomografía Computarizada por Tomografía Computarizada de Emisión de Fotón Único , Tecnecio Tc 99m Sestamibi , Diagnóstico Precoz , Femenino , Humanos , Hiperparatiroidismo Primario/sangre , Hiperparatiroidismo Primario/metabolismo , Masculino , Persona de Mediana Edad , Hormona Paratiroidea/sangre , Radiofármacos/farmacocinética , Estudios Retrospectivos , Tecnecio Tc 99m Sestamibi/farmacocinética
8.
Mayo Clin Proc ; 50(2): 85-90, 1975 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-123293

RESUMEN

This report records the congenital and acquired abnormalities observed during the first 4 days of life in 21,142 live-born infants. Gross abnormalities observed in 300 stillborns also are recorded. The abnormalities are those thought to be of clinical or possibly clinical significance. Also included are other conditions ordinarily not considered to be a congenital abnormality, such as convulsions. Definitions are given when indicated. The incidence rates per 1,000 births for specific malformation noted in the first 4 days of life are provided for all births, for live births, for live births under 2,500 g, and for stillbirths. The need for accurate studies of specific forms of congenital malformations is reiterated. The rate for all malformations combined is not given since it is difficult to interpret or use for comparisons because of variations in the definition of malformation and in completeness of ascertainment in different studies.


Asunto(s)
Anomalías Congénitas/epidemiología , Muerte Fetal , Enfermedades del Recién Nacido/epidemiología , Recien Nacido Prematuro , Convulsiones/epidemiología , Peso al Nacer , Síndrome de Down/epidemiología , Femenino , Muerte Fetal/epidemiología , Cardiopatías Congénitas/epidemiología , Humanos , Recién Nacido , Masculino , Minnesota , Embarazo
9.
Org Lett ; 3(4): 615-7, 2001 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-11178839

RESUMEN

[reaction: see text] High stereoselectivities (up to 98% de) have been achieved for the Lewis acid-mediated cross-coupling reaction of dimethyl acetals to a chiral 1,3-thiazolidine-2-thione-derived titanium enolate. The reaction affords enantiopure anti alpha-methyl-beta-alkoxy carbonyl compounds in a wide range of acetals.

10.
Hepatogastroenterology ; 45(24): 2110-4, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9951874

RESUMEN

Complications of liver hydatid disease include those related to the compression of adjacent viscus, to the infection of the cyst's contents or to the perforation of the cyst. Perforations into hollow abdominal organs are rare, and can occur secondary to the infection of the cyst or to a primary pathology of the perforated organ. We report on 2 cases of perforation of a liver cyst into the duodenum, 1 due to the presence of a duodenal ulcer, and 1 secondary to a hydatid abscess. The surgical treatment of the lesions and their complications was, in both cases, successful.


Asunto(s)
Enfermedades Duodenales/diagnóstico , Equinococosis Hepática/diagnóstico , Perforación Intestinal/diagnóstico , Anciano , Anciano de 80 o más Años , Enfermedades Duodenales/patología , Úlcera Duodenal/diagnóstico , Úlcera Duodenal/patología , Duodeno/patología , Equinococosis Hepática/patología , Femenino , Humanos , Perforación Intestinal/patología , Hígado/patología , Absceso Hepático/diagnóstico , Absceso Hepático/patología , Rotura Espontánea
11.
Rev Esp Med Nucl Imagen Mol ; 33(6): 358-65, 2014.
Artículo en Español | MEDLINE | ID: mdl-25107596

RESUMEN

Radioguided surgery can be a useful technique in the localization of neuroendocrine tumors. It detects more and smaller lesions compared to pre-surgical imaging and intraoperative digital palpation by the surgeon. It detects residual lesions and also indicates the shortest access route to the lesion. Nevertheless, its use has not become widespread because of technical difficulties. There is a limited number of published series, a lack of standardized protocol because of the great variability regarding type of radiopharmaceutical, dose of radiotracer, timing between injection and surgery. In this paper, we review these issues, describing the experience of different authors in diverse tumors.


Asunto(s)
Tumores Neuroendocrinos/cirugía , Radiografía Intervencional/métodos , Cirugía Asistida por Computador/métodos , Humanos , Proteínas de Neoplasias/análisis , Tumores Neuroendocrinos/química , Radiofármacos/análisis , Radiofármacos/farmacocinética , Receptores de Somatostatina/análisis , Somatostatina/análogos & derivados
12.
Rev Esp Med Nucl Imagen Mol ; 32(4): 260-2, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23267742

RESUMEN

We present a case of a 78-year-old female with effort angina. A myocardial perfusion SPECT (MPS) showed increased tracer uptake in two synchronic tumor lesions, a thymoma and a breast cancer. This case highlights the contribution of SPECT-CT in the characterization of these findings and its essential role in rapid decision-making. The patient underwent surgery of both lesions that had gone undetected prior to the conduction of the MPS.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Imagen de Perfusión Miocárdica , Radiofármacos , Tecnecio Tc 99m Sestamibi , Timoma/diagnóstico por imagen , Tomografía Computarizada de Emisión de Fotón Único , Anciano , Femenino , Humanos , Hallazgos Incidentales
13.
Rev Esp Med Nucl Imagen Mol ; 31(5): 275-7, 2012 Sep.
Artículo en Inglés, Español | MEDLINE | ID: mdl-23067531

RESUMEN

A common cause for surgical failure of primary hyperparathyroidism (pHPT) is the non-detection of an ectopic adenoma during the intervention. We present a case of a patient with pHPT in whom an ectopic gland was found in the right retropharyngeal space by means of a double phase (99m)Tc-methoxy-isobutyl-isonitrile ((99m)Tc-MIBI) scintigraphy and early SPECT-CT after several surgeries and imaging tests. The addition of a tomography to the planar scintigraphy increases its sensitivity and improves pathological parathyroid glands localization. The hybrid imaging is sometimes essential to obtain surgical success, as in the case of ectopic adenomas.


Asunto(s)
Adenoma/diagnóstico por imagen , Coristoma/diagnóstico por imagen , Hiperparatiroidismo Primario/diagnóstico por imagen , Imagen Multimodal , Neoplasias de las Paratiroides/diagnóstico por imagen , Enfermedades Faríngeas/diagnóstico por imagen , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X , Adenoma/complicaciones , Adenoma/cirugía , Coristoma/complicaciones , Coristoma/cirugía , Femenino , Humanos , Hipercalcemia/etiología , Hiperparatiroidismo Primario/etiología , Cálculos Renales/etiología , Persona de Mediana Edad , Neoplasias de las Paratiroides/complicaciones , Neoplasias de las Paratiroides/cirugía , Enfermedades Faríngeas/complicaciones , Enfermedades Faríngeas/cirugía , Radiofármacos , Reoperación , Tecnecio Tc 99m Sestamibi
14.
Rev Esp Sanid Penit ; 12(1): 37-46, 2010 Jun.
Artículo en Español | MEDLINE | ID: mdl-23128487

RESUMEN

To be fully in accordance with constitutional doctrines the notion of conscientious objection must be understood as a manifestation of the fundamental right to ideological freedom as contained in art. 16.1 CE (assuming of course that all objecting conduct is legitimate), but it must also be understood as a principle. That is to say, any conflict between the subject's fundamental right and legal duty that he rejects must be resolved by the judge who must make a careful judgement of values and property. This fundamental right still exists and may invoked and exercised by inmates and health personnel in the prison context in the face of predictions of the forcible imposition of medical treatment as stated in the LOGP and RP, with no more limit than public order itself.

16.
Ann Trop Med Parasitol ; 101(8): 689-94, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18028730

RESUMEN

Although human mucosal leishmaniasis is much more common in Latin America, a few cases that are the result of local transmission occur in Europe. A suspected case of leishmaniasis is usually confirmed by the demonstration of amastigotes in smears, the culture of promastigotes from blood or tissue samples, or the PCR-based demonstration of leishmanial DNA. Biopsies may contain too few parasites to be found positive by microscopy or culture, however, and then a diagnosis may be difficult, especially in regions where human leishmaniasis in general or particular forms of the disease are rarely seen. The aim of the present study was to investigate the histopathological characteristics of three Spanish cases of non-granulomatous mucosal leishmaniasis caused by Leishmania infantum. The hope was that the information collected will help European clinicians diagnose such cases, even when amastigotes cannot be readily demonstrated.


Asunto(s)
Leishmania infantum/aislamiento & purificación , Leishmaniasis Mucocutánea/patología , Adulto , Animales , Antiprotozoarios/uso terapéutico , Diagnóstico Diferencial , Femenino , Humanos , Leishmaniasis Mucocutánea/tratamiento farmacológico , Leishmaniasis Mucocutánea/parasitología , Masculino , Persona de Mediana Edad , España/epidemiología , Resultado del Tratamiento
18.
Infection ; 34(3): 176-80, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16804664

RESUMEN

The papillary squamous cell carcinoma (PSCC) is a rare variant of the head and neck squamous cell carcinoma. Established etiological factors can include tobacco smoking and heavy alcohol abuse. Moreover, human papillomavirus infection can be involved in the pathogenesis of PSCC. This tumor is more frequent in patients with immunosuppression including those who have received a transplant. Most of the cases are produced by genotype HPV-6 and HPV-16, although there is a possibility of infection by other HPV subtypes. We present a case report of a PSCC and papilloma with oropharyngeal location in which high-risk HPV type 16 and low-risk HPV type 6, respectively, were identified by PCR in a renal transplant patient.


Asunto(s)
Carcinoma de Células Escamosas/etiología , Trasplante de Riñón/efectos adversos , Neoplasias Orofaríngeas/etiología , Infecciones por Papillomavirus/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Orofaríngeas/patología , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/patología , Infecciones por Papillomavirus/transmisión
19.
Phys Rev Lett ; 86(26 Pt 1): 5858-61, 2001 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-11415379

RESUMEN

We propose a method for implementing the large- N(c), large-N(f) limit of QCD at the effective Lagrangian level. Depending on the value of the ratio N(f)/N(c), different patterns of chiral symmetry breaking can arise, leading in particular to different behaviors of the eta(') mass in the combined large-N limit.

20.
Phys Rev Lett ; 89(16): 161802, 2002 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-12398714

RESUMEN

We discuss forward-backward charge asymmetries for lepton-pair production in association with a large-transverse-momentum jet at hadron colliders. The lepton charge asymmetry relative to the jet direction A(j)(FB) gives a new determination of the effective weak mixing angle sin((2)theta(lept)(eff)(M(2)(Z)) with a statistical precision after cuts of approximately 10(-3) (8x10(-3)) at LHC (Tevatron). This is to be compared with the current uncertainty at LEP and SLD from the asymmetries alone, 2x10(-4). The identification of b jets also allows for the measurement of the bottom-quark-Z asymmetry A(b)(FB) at hadron colliders, the resulting statistical precision for sin((2)theta(lept)(eff)(M(2)(Z)) being approximately 9x10(-4) (2x10(-2) at Tevatron), also lower than the reported precision at e(+)e(-) colliders, 3x10(-4).

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