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1.
Phys Rev Lett ; 93(24): 242001, 2004 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-15697795

RESUMEN

We report the first observation of a charm-strange meson D(+)(sJ)(2632) at a mass of 2632.5+/-1.7 MeV/c(2) in data from SELEX, the charm hadro-production experiment E781 at Fermilab. This state is seen in two decay modes, D(+)(s)eta and D0K+. In the D(+)(s)eta decay mode we observe a peak with 101 events over a combinatoric background of 54.9 events at a mass of 2635.4+/-3.3 MeV/c(2). There is a corresponding peak of 21 events over a background of 6.9 at 2631.5+/-2.0 MeV/c(2) in the decay mode D0K+. The decay width of this state is <17 MeV/c(2) at 90% confidence level. The relative branching ratio Gamma(D0K+)/Gamma(D(+)(s)eta) is 0.14+/-0.06. The mechanism that keeps this state narrow is unclear. Its decay pattern is also unusual, being dominated by the D(+)(s)eta decay mode.

2.
Phys Rev Lett ; 89(12): 121802, 2002 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-12225078

RESUMEN

We report results on event-by-event fluctuations of transverse momentum, Phi(p(t)), in pi(+)p and K(+)p collisions at 250 GeV/c. For the first time, their dependence on rapidity region, transverse momentum acceptance, multiplicity, mean transverse momentum per event, and on the correlation between transverse momentum and multiplicity are systematically presented. The results are compared with those from the PYTHIA Monte Carlo generator. The fluctuations under the same acceptance cuts as used in current heavy-ion experiments are also presented.

3.
Phys Rev Lett ; 89(11): 112001, 2002 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-12225136

RESUMEN

We observe a signal for the doubly charmed baryon Xi(+)(cc) in the charged decay mode Xi(+)(cc)-->Lambda(+)(c)K-pi(+) in data from SELEX, the charm hadroproduction experiment at Fermilab. We observe an excess of 15.9 events over an expected background of 6.1+/-0.5 events, a statistical significance of 6.3sigma. The observed mass of this state is 3519+/-1 MeV/c(2). The Gaussian mass width of this state is 3 MeV/c(2), consistent with resolution; its lifetime is less than 33 fs at 90% confidence.

4.
Phys Rev Lett ; 86(23): 5243-6, 2001 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-11384468

RESUMEN

We report new precision measurements of the lifetimes of the Lambda(+)(c) and D0 from SELEX, the charm hadroproduction experiment at Fermilab. Based upon 1630 Lambda(+)(c) and 10 210 D0 decays we observe lifetimes of tau[Lambda(+)(c)] = 198.1+/-7.0+/-5.6 fs and tau[D0] = 407.9+/-6.0+/-4.3 fs.

5.
Phys Rev Lett ; 84(9): 1857-61, 2000 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-21923211

RESUMEN

We report the first observation of the Cabibbo-suppressed charm baryon decay Ξ_{c}^{+}→pK^{-}π^{+}. We observe 150±22±5 events for the signal. The data were accumulated using the SELEX spectrometer during the 1996-1997 fixed target run at Fermilab, chiefly from a 600 GeV/c Σ^{-} beam. The branching fractions of the decay relative to the Cabibbo-favored Ξ_{c}^{+}→Σ^{+}K^{-}π^{+} and Ξ_{c}^{+}→Ξ^{-}π^{+}π^{+} are measured to be B(Ξ_{c}^{+}→pK^{-}π^{+})/B(Ξ_{c}^{+}→Σ^{+}K^{-}π^{+})=0.22±0.06±0.03 and B(Ξ_{c}^{+}→pK^{-}π^{+})/B(Ξ_{c}^{+}→Ξ^{-}π^{+}π^{+})=0.20±0.04±0.02, respectively.

6.
Eur Respir J ; 11(3): 706-11, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9596125

RESUMEN

T-cell types are important in maintaining immune homeostasis in the lung and their imbalance may be associated with several diseases. We examined the relationship between bronchoalveolar lavage (BAL) T-cell subset profiles and the clinical course of 46 patients with idiopathic pulmonary fibrosis (IPF). A flow cytometry cell sorter (FACS) was used to analyse the T-cell subsets. Pulmonary function tests (PFT) were performed at baseline and 6-12 months later. Patients were divided into two groups according to their CD4/CD8 ratio: CD4/CD8 >1 (group 1, n=21); and CD4/CD8 <1 (group 2, n=25). A lower percentage of lymphocytes, a higher percentage of CD8/S6F1 cells (cytotoxic T-lymphocytes) and a higher percentage of neutrophils were found in the BAL in group 2 compared to group 1 (11+/-7.5% versus 19+/-13.2%; p=0.024 and 29.8+/-17.6% versus 13.3+/-6.9%; p=0.068, respectively for lymphocytes and cytotoxic T-lymphocytes; and 8+/-11% versus 29+/-27%; p=0.003 for neutrophils). Inversely, in the peripheral blood, the distribution of CD8/S6F1 cells was lower in group 1 than in group 2 (8.3+/-6.9% versus 33.4+/-16.5%; p=0.0048). The patients were followed over a period of 1 yr in order to test whether those findings could determine efficacy of therapy. The baseline transfer factor of the lung for carbon monoxide (TL,CO) capacity in group 1 and group 2 was 59+/-22% and 51+/-21%, respectively (p=0.29), but only in group 1 was the TL,CO capacity improved significantly in response to steroids treatment after 6-12 months. IPF patients with a higher percentage of lymphocytes, a lower percentage of neutrophils, CD4/CD8 >1 and a low percentage of CD8/S6F1 may have a more benign course of disease. These parameters may identify an early stage of reversible disease responsive to therapy. We conclude that these measurements may be a useful tool in monitoring response to treatment in patients with idiopathic pulmonary fibrosis.


Asunto(s)
Glucocorticoides/uso terapéutico , Prednisona/uso terapéutico , Fibrosis Pulmonar/tratamiento farmacológico , Subgrupos de Linfocitos T/inmunología , Líquido del Lavado Bronquioalveolar/citología , Relación CD4-CD8 , Recuento de Células , Separación Celular , Femenino , Citometría de Flujo , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Fibrosis Pulmonar/diagnóstico , Fibrosis Pulmonar/epidemiología , Fibrosis Pulmonar/inmunología , Pruebas de Función Respiratoria , Factores de Tiempo
8.
Clin Chem ; 39(2): 271-7, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8432016

RESUMEN

The Reflotron HDL Cholesterol test (Boehringer Mannheim GmbH) directly separates and analyzes high-density lipoprotein (HDL) cholesterol in plasma collected with EDTA in an integrated dry-reagent system suitable for alternative site testing of lipoproteins. We describe a multicenter evaluation of this test by two US and six European laboratories experienced in lipid analysis. Each laboratory compared the Reflotron with the same conventional wet-chemistry method, Boehringer phosphotungstate-Mg2+ precipitation with enzymatic cholesterol assay. Imprecision was within accepted guidelines, with CVs of < or = 8% for fresh and frozen plasmas (median CV 1.7-3.9%) and for lyophilized sera (median CV 3.8-4.7%), similar to those of the conventional method. Results of linear-regression analysis were as follows: Reflotron HDL Cholesterol = 1.03 conventional - 3.9 mg/L, r = 0.987. The Reflotron results were somewhat low in the two US laboratories, demonstrating the need for general standardization of methods for measuring HDL cholesterol. Results from capillary fingerstick plasma agreed well with those from venous-derived plasma; capillary = 1.04 venous + 4.5 mg/L, r = 0.967. The system is relatively insensitive to interference from hemoglobin (< or = 0.75 g/L), ascorbic acid (< or = 0.3 g/L), bilirubin (< or = 50 mg/L), cholesterol (< or = 3.5 g/L), and triglycerides (< or = 4 g/L). The relative ease of operation and the rapid availability of results (within 90 s for plasma collected in EDTA) make the method appropriate for use by well-trained, but not necessarily technical, operators in the physician's office or other alternative sites.


Asunto(s)
HDL-Colesterol/sangre , Juego de Reactivos para Diagnóstico , Aminopirina , Capilares , Precipitación Química , Colesterol Oxidasa , Ácido Edético , Estudios de Evaluación como Asunto , Humanos , Magnesio , Ácido Fosfotúngstico , Fotometría , Control de Calidad , Juego de Reactivos para Diagnóstico/normas , Juego de Reactivos para Diagnóstico/estadística & datos numéricos , Análisis de Regresión , Venas
9.
Allergy ; 44(6): 385-95, 1989 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2802112

RESUMEN

IgE and IgG antibody response to birch pollen antigens were studied by means of immunoblotting experiments testing 58 sera from patients with Type I allergy to birch pollen. 56/58 patients showed IgE antibodies reactive with Bet v I, a 17 kilodalton (kD) pollen protein. 2D-electrophoresis/immunoblot revealed a heterogeneity of that protein. Ten spots (pH 4.9-5.9) could be detected, presumably representing differentially glycosylated isoallergens. In 33/58 patients, there was no evidence of IgE antibodies directed against allergens other than Bet v I. However, in 25/58 of patients' sera, 11 minor allergens (13, 15, 18, 27, 29, 32, 39, 44, 57, and 68 kD) with individual incidences from 1.7% to 17.2% were identified. All proteins were also recognized by the patients' IgG antibodies: in the case of Bet v I recognition was weak, whereas the IgG response to the minor allergens was pronounced. Sera from healthy individuals showed similar IgG antibody responses, but no IgG to the 15, 27, and 29 kD proteins. Our results suggest that IgG directed against minor allergens may function as trapping antibodies in healthy individuals. Too low or lacking amounts of anti-Bet v I IgG may facilitate an allergic reaction.


Asunto(s)
Alérgenos/inmunología , Inmunoglobulina E/biosíntesis , Inmunoglobulina G/biosíntesis , Polen/inmunología , Rinitis Alérgica Estacional/inmunología , Adolescente , Adulto , Especificidad de Anticuerpos , Niño , Electroforesis en Gel Bidimensional , Femenino , Humanos , Isotipos de Inmunoglobulinas/biosíntesis , Masculino , Persona de Mediana Edad , Peso Molecular , Árboles
10.
Int Arch Allergy Appl Immunol ; 88(1-2): 180-2, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2707881

RESUMEN

58 sera from patients with established birch pollen allergy showed characteristic antibody-binding patterns in immunoblotting experiments. Regarding IgE, 56/58 patients recognized a protein of molecular weight (MW) 17 kilodaltons (kD), previously defined as Bet v I. 23/58 patients in addition reacted with a variety of 11 minor allergens with MWs ranging from 13 to 68 kD. A 13-kD protein was proved to represent an independent minor allergen. IgG binding in patients and healthy individuals was more pronounced on the minor allergens than on Bet v I. 3 different allergens were not detected by IgG of healthy individuals. In two-dimensional electrophoresis/immunoblot, a monoclonal antibody and human IgE (in both cases directed against Bet v I) detected a very similar cluster of spots, probably representing isoallergens of Bet v I.


Asunto(s)
Alérgenos/inmunología , Hipersensibilidad/inmunología , Inmunoglobulina E/inmunología , Inmunoglobulina G/inmunología , Polen/inmunología , Árboles , Animales , Anticuerpos Monoclonales/inmunología , Especificidad de Anticuerpos , Electroforesis en Gel Bidimensional , Humanos , Isotipos de Inmunoglobulinas/inmunología , Ratones
11.
J Clin Chem Clin Biochem ; 25(2): 61-70, 1987 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3553415

RESUMEN

The protein pattern of cerebrospinal fluid (CSF) of 334 patients with various neurological and systemic diseases was investigated by high resolution two-dimensional electrophoresis (2-DE). 2-DE gels of normal CSF contain proteins which are not detectable in 2-DE gels of serum. Disturbances of the blood-brain or blood-CSF barrier, and degenerative diseases of the brain and malignant diseases produce specific changes on 2-DE gels of the CSF. The appearance of 10 spot areas in the light chain region of 2-DE gels seem to be connected with the diagnosis of multiple sclerosis. The sensitivity and the specificity of these spot areas for the diagnosis of multiple sclerosis are described. Proteins within the ten spot areas are immunoglobulin light chains or substances which cross-react very strongly with light chain antibodies as demonstrated by immunoblotting and immunoabsorption.


Asunto(s)
Proteínas del Líquido Cefalorraquídeo/análisis , Enfermedades del Sistema Nervioso/líquido cefalorraquídeo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Electroforesis en Gel de Poliacrilamida , Humanos , Inmunoglobulina G/líquido cefalorraquídeo , Técnicas de Inmunoadsorción , Persona de Mediana Edad , Esclerosis Múltiple/líquido cefalorraquídeo
13.
J Clin Chem Clin Biochem ; 24(12): 981-92, 1986 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3819656

RESUMEN

The proteins of solid lung tumours (15 adenocarcinomas and 10 squamous cell carcinomas) were examined by high resolution two-dimensional electrophoresis (2-DE) and compared with the proteins of adjacent lung tissue which demonstrated no histological evidence of malignant transformation, and with the proteins of other malignant tumours and normal tissues. To investigate tumour cell-specific protein synthesis, we isolated malignant and normal cells enzymatically with collagenase, elastase, and DNase. Tissue and tumour cells were enriched in an additional step on a Percoll gradient. The 2-DE gel patterns derived from entire tissue and enriched tissue cell preparations were compared. No specific differences were found between the 2-DE protein patterns from adenocarcinomas and squamous cell carcinomas of the lung, but three proteins identified on the 2-DE gels appeared to be tumour-associated. Spot A is present in non-neoplastic and neoplastic epithelial tissues. Spot B is pronounced in 2-DE gels of sarcomas, but is also present in preparations of other malignant tissues. Spot C is present in all malignant cell preparations. These three spots were also demonstrated in 2-DE protein patterns from tissue cultures of malignant cell lines. Spot B and spot C were also present in some normal tissues.


Asunto(s)
Neoplasias Pulmonares/análisis , Proteínas de Neoplasias/aislamiento & purificación , Adenocarcinoma/análisis , Carcinoma de Células Escamosas/análisis , Línea Celular , Electroforesis en Gel de Poliacrilamida , Humanos , Focalización Isoeléctrica
14.
J Clin Chem Clin Biochem ; 22(1): 53-9, 1984 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-6699552

RESUMEN

High resolution two dimensional electrophoresis, one of the most potent methods for the analytical separation of proteins, is still used only in specialized laboratories. The present paper describes a two dimensional electrophoresis method, which permits characterization of abnormal serum proteins (paraproteins) and is suitable for application in a clinical laboratory. Both steps of the electrophoresis are performed by the "flat bed technique". The critical transfer from the isoelectric focusing step to the gel of the second dimension is facilitated by use of specially prepared foil stencils. The practicality of the procedure was considerably increased by using commercially available materials such as gels for isoelectric focusing and the silver stain kit. The analysis can be calibrated by measurement of the pH gradient and by using molecular weight protein standards. Moreover, two different samples can be analysed simultaneously in the same gels of the first and the second dimension. This permits a direct comparison of the sample of interest with the sample of reference. Serum samples showing an abnormal band ("M gradient") in routine methods such as agarose gel electrophoresis, were analysed by the described method. Some "M gradients" consisted of single abnormal proteins. Another sample showed a "M gradient" composed of a number of abnormal protein spots in our method. Questions concerning pathobiological and clinical evaluation of the findings justify further studies using this method.


Asunto(s)
Paraproteínas/análisis , Electroforesis en Gel de Agar/métodos , Humanos , Focalización Isoeléctrica , Péptidos/análisis , Dodecil Sulfato de Sodio
16.
Cancer Chemother Pharmacol ; 11(3): 172-6, 1983.
Artículo en Inglés | MEDLINE | ID: mdl-6640824

RESUMEN

The usefulness of a diffusion chamber method for determination of concentrations of cytostatic drugs in the interstitial fluid of tissues was tested. Chambers with a permeable membrane (pore size: 0.45 micrometer) were implanted in the liver, kidney, bladder wall, and prostate of dogs. After administration of high doses of methotrexate (100 mg/kg body wt) the concentrations in the chamber fluid and in serum were measured simultaneously and repeatedly for 72 h. The method proved to be effective for collecting data on the distribution of drugs in different organs. The results show that knowledge of the serum concentration does not permit predictions of the drug concentration in the interstitial fluid of various tissues to be made.


Asunto(s)
Metotrexato/metabolismo , Animales , Difusión , Perros , Riñón/metabolismo , Cinética , Hígado/metabolismo , Masculino , Metotrexato/administración & dosificación , Modelos Biológicos , Próstata/metabolismo , Vejiga Urinaria/metabolismo
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