Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 39
Filtrar
Más filtros

Tipo del documento
Intervalo de año de publicación
1.
Phys Rev Lett ; 130(9): 091801, 2023 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-36930908

RESUMEN

The SNO+ Collaboration reports the first evidence of reactor antineutrinos in a Cherenkov detector. The nearest nuclear reactors are located 240 km away in Ontario, Canada. This analysis uses events with energies lower than in any previous analysis with a large water Cherenkov detector. Two analytical methods are used to distinguish reactor antineutrinos from background events in 190 days of data and yield consistent evidence for antineutrinos with a combined significance of 3.5σ.

2.
Phys Rev Lett ; 106(4): 041804, 2011 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-21405321

RESUMEN

The TWIST Collaboration has completed a new measurement of the energy-angle spectrum of positrons from the decay of highly polarized muons. A simultaneous measurement of the muon decay parameters ρ, δ, and P(µ)(π)ξ tests the standard model in a purely leptonic process and provides improved limits for relevant extensions to the standard model. Specifically, for the generalized left-right symmetric model |(g(R)/g(L))ζ|<0.020 and (g(L)/g(R))m(2)>578 GeV/c(2), both 90% C.L.

3.
Phys Rev Lett ; 94(10): 101805, 2005 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-15783475

RESUMEN

The TWIST Collaboration has measured the Michel parameter rho in normal muon decay, mu(+)--> e(+)nu(e)nu (mu). In the standard model, rho = 3/4. Deviations from this value imply mixing of left- and right-handed muon and electron couplings. We find rho=0.750 80+/-0.000 32(stat) +/- 0.000 97(syst) +/- 0.000 23, where the last uncertainty represents the dependence of rho on the Michel parameter eta. This result sets new limits on the W(L)-W(R) mixing angle in left-right symmetric models.

5.
Clin Nutr ; 22(1): 81-6, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12553954

RESUMEN

OBJECTIVE: To evaluate the effects of the metabolic control of the insulin-dependent diabetes mellitus (IDDM) on the nutritional status of vitamin E. METHODS: A total of 47 children with IDDM and a mean age of 11.91+/-1.60 (mean+/-SD) years were studied, matched for age and sex with 16 healthy children (11.75+/-1.83 years). Following the American and British Associations for IDDM, we used a classification of "good", "moderate" or "poor" control of the illness: (a) good control [glycosilated haemoglobin (HbAlc) < or =7%]; (b) moderate control (7%< HbAlc < or =8%); and (c) poor control (HbAlc>8%). Serum concentrations of total cholesterol (CHOL), triglycerides (TG), high-density lipoproteins-cholesterol (HDLc), very low- and low-density lipoproteins cholesterol (VLDLc and LDLc), plasma and erythrocyte vitamin E (Vit Ep and Vit Ee) and plasma vitamin A (Vit Ap) were measured in all children. RESULTS: The children with "poor" metabolic control of the illness presented significantly higher plasma concentrations of CHOL, LDLc, VLDLc, LDLc/HDLc, (VLDL+LDL)c/HDLc, TG and Vit Ep; higher indices Vit Ep/Vit Ee and Vit Ep/Vit Ap relative to those with a "good" control of the illness. Direct-linear correlations were found between Vit Ep and the percentage of HbAlc and with the markers of atherogenic risk in the IDDM children. CONCLUSION: There is a significant rise in Vit Ep concentrations as metabolic control of the illness worsens, whereas Vit Ee remained unchanged. These results suggest that vitamin E maintains its nutritional status despite a poor control of the IDDM during childhood.


Asunto(s)
Diabetes Mellitus Tipo 1/metabolismo , Estado Nutricional/fisiología , Vitamina E/sangre , Adolescente , Análisis de Varianza , Biomarcadores , Niño , Colesterol/sangre , Femenino , Hemoglobina Glucada/análisis , Humanos , Lipoproteínas/sangre , Masculino , Factores de Riesgo , Triglicéridos/sangre , Vitamina A/sangre
6.
Eur J Clin Nutr ; 56(1): 44-50, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11840179

RESUMEN

OBJECTIVE: A case-control study was conducted to evaluate the effects of type 1 diabetes mellitus (IDDM) on plasma levels of vitamin A (retinol) and serum levels of retinol-binding protein (RBP) and their relationship with the atherogenic indicators. SUBJECTS: A total of 47 randomised IDDM children were recruited from those treated at the Endocrinology Unit of the University Hospital of Granada (Spain). They were matched for age and sex with 16 healthy children. METHODS: The following parameters were measured in all patients: serum concentrations of total cholesterol, triglycerides, high (HDL, spectrophotometry), very low (VLDL) and low (LDL) density lipoprotein cholesterol (Friedewald's formula); serum levels of RBP (kinetic nephelometry); plasma vitamin A and glycosilated haemoglobin (HbA1c; high performance chromatography). RESULTS: Higher RBP concentrations in IDDM children (P=0.05), lower retinol levels (P=0.05) and lower vitamin A/cholesterol ratio (P=0.02) than in the control group were found; no differences in the atherogenic indicators were observed. There was a correlation between RBP and vitamin A (P=0.0001). Relationships between retinol, RBP and atherogenic indicators were demonstrated in the IDDM group (A-LDLc/HDLc (P=0.01); A-(VLDL+LDL)c/HDLc (P=0.007); RBP-LDLc/HDLc (P=0.05); RBP-(VLDL+LDL)c/HDLc (P=0.02)), and an inverse relationship was found between the vitamin A/TG ratio and HbA1c (P=0.004). The children with HbA1c>8% showed increased atherogenic indicators and lower vitamin A/CHOL and vitamin A/TG ratios than those with good control of the illness. CONCLUSIONS: The IDDM children with poor metabolic control face a higher atherogenic risk and vitamin A 'relative deficiency' risk than those with good metabolic control of their illness. Relationships between retinol and RBP with atherogenic indicators were found. The results suggest that vitamin A therapeutic supplements in IDDM children may reduce or prevent atherogenic risk.


Asunto(s)
Diabetes Mellitus Tipo 1/sangre , Lípidos/sangre , Proteínas de Unión al Retinol/análisis , Vitamina A/sangre , Adolescente , Análisis de Varianza , Niño , Femenino , Humanos , Masculino , Proteínas Plasmáticas de Unión al Retinol , Índice de Severidad de la Enfermedad , Factores de Tiempo
7.
AIDS ; 15(14): 1904-6, 2001 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-11579263

RESUMEN

Structured treatment interruption strategies may help overcome problems of highly active antiretroviral therapy, but might also represent a cause of stress. We present data that indicate a psychological benefit from structured treatment interruption. Although some disturbances appear at the resumption of therapy, no definitive problems are found that preclude such therapeutic approaches from a psychological perspective. However, a close follow-up of patients during interruption periods is advisable to avoid difficulties reported at treatment resumption presenting a risk to patients' health.


Asunto(s)
Terapia Antirretroviral Altamente Activa , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/psicología , VIH-1/aislamiento & purificación , Carga Viral , Esquema de Medicación , VIH-1/fisiología , Humanos , Calidad de Vida , ARN Viral/sangre
8.
Early Hum Dev ; 65 Suppl: S103-10, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11755041

RESUMEN

We analyze markers of carnitine insufficiency and deficiency, lysine (LYS) and methionine (MET), in 39 neonates with intrapartum hypoxia (selection criteria: umbilical artery pH <7.20, lactate >1.8 mmol/l and PaO2 <25 mm Hg), and in 35 healthy newborn infants (control group) in the early neonatal period (1-7 days of life). Free (FC), total (TC) carnitine and acylcarnitines (AC=short-chain+long-chain acylcarnitines) were measured using a radioisotopic micromethod; LYS and MET were determined by high-pressure liquid chromatography. AC and TC plasma concentrations and AC/FC ratio were higher while FC/TC ratio was lower in the hypoxic neonates than in the control group. Hypoxic newborn infants (59%) presented "carnitine deficiency" (FC/TC <0.7) and 60% of them "carnitine insufficiency" (AC/FC ratio >0.4) vs. 31% and 28%, respectively, for the neonates of the control group (p<0.05). In the healthy neonates group, MET correlated with FC/TC and the AC/FC ratio. FC, TC, AC, AC/FC and umbilical artery pH (pHua) were inversely correlated. FC/TC and MET correlated with pHua. We conclude that: (1) an important percentage of newborn infants with intrapartum hypoxia suffer carnitine deficiency and carnitine insufficiency in the early neonatal period, related to MET plasma levels; (2) the carnitine deficiency or insufficiency in the neonate is determined by the degree of intrapartum acidosis.


Asunto(s)
Carnitina/análogos & derivados , Carnitina/deficiencia , Hipoxia Fetal/complicaciones , Estado Nutricional , Carnitina/sangre , Cromatografía Líquida de Alta Presión , Ésteres/sangre , Hipoxia Fetal/sangre , Edad Gestacional , Humanos , Concentración de Iones de Hidrógeno , Recién Nacido , Lisina/sangre , Metionina/sangre
9.
Early Hum Dev ; 65 Suppl: S173-82, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11755049

RESUMEN

The diet of the breast-feeding mother impacts on the quality and quantity of the milk that she feeds her child. Milk can be a vehicle for toxins, such as drugs and their metabolites, viruses, nicotine, caffeine, alcohol, and organochlorine molecules such as PCBs, DDT, HCB, HCH and dioxins, which can harm the health of the breast-feeding child. The 24-h recall diet was considered appropriate to adequately study the diet of breast-feeding mothers and was used in the present preliminary study to establish the possible relationship between the food items consumed and the presence of pesticides in her milk. Two groups of randomly selected healthy breast-feeding volunteers aged between 17 and 35 years from two different areas were recruited: 34 from intensive agriculture zone, El Ejido (Almeria), from the "Hospital de Poniente" and 21 urban zone, the city of Granada, from the "Clinico" University Hospital. Application of the Spearman Correlation Test to the results from Almeria showed a certain positive correlation between the total intake of fats and both the p,p'DDD (rho=0.53, p< or =0.05) and methoxychlor (rho=0.48, p< or =0.05) in mature milk, and between the energy supplied by vegetables and the endosulfan-lactone in mature milk (rho=0.50, p< or =0.05). Among the group of breast-feeding women from Granada, there was a strong correlation between the intake of fats and both the p,p'DDT in transition milk (rho=0.90, p< or =0.05) and the p,p'DDD in mature milk (rho=0.90, p< or =0.05). In conclusion, there is a statistically significant relationship between the consumption of fatty foods and some organochlorine molecules and between the consumption of vegetables and pesticides, and the latter relationship occurs in Almeria but not in Granada.


Asunto(s)
Dieta , Insecticidas/análisis , Leche Humana/química , Adolescente , Adulto , Agricultura , Lactancia Materna , DDT/análisis , Grasas de la Dieta/administración & dosificación , Femenino , Humanos , Metoxicloro/análisis , Verduras
10.
Early Hum Dev ; 65 Suppl: S183-90, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11755050

RESUMEN

In the face of evidence of human milk contamination by organochlorine pesticides, an analysis was performed on samples of milk obtained from healthy lactating women in the provinces of Granada and Almeria in Southern Spain. The samples were obtained by the Neonate Section of the Department of Pediatrics of Granada University Hospital (Neonatology Division) and by the Neonatal Service of Poniente Hospital in El Ejido, Almería. A liquid-liquid extraction procedure was performed. The cleaning of the sample before gas chromatography-mass spectrometry (GC-MS) used silica Sep-Pak. Among other pesticides, aldrin, dieldrin, DDT and its metabolites, lindane, methoxychlor and endosulfan were identified. The presence of these products was confirmed by mass spectrometry. The identification and quantification of these organochlorine molecules is important because they have estrogenic effects.


Asunto(s)
Hidrocarburos Clorados , Insecticidas/análisis , Leche Humana/química , Lactancia Materna , Calostro/química , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , España
11.
J Acquir Immune Defic Syndr ; 25(3): 221-8, 2000 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-11115952

RESUMEN

BACKGROUND: Nearly perfect compliance seems to be indispensable to obtain the maximum benefit from highly active antiretroviral therapy (HAART). Interventions to ensure a high level of adherence during a relatively long-term period of therapy are necessary. METHODS: This is a prospective, randomized, two-arm controlled study including patients starting their first-or second-line HAART who were randomized to receive psychoeducative intervention to implement adherence (experimental group [EG]) or a usual medical follow-up (control group [CG]). We aimed to study the efficacy of a psychoeducative intervention to ensure long-term adherence to HAART, its relation with the virologic efficacy of treatment, and to determine the variables related to long-term adherence. Visits were made at weeks 0, 4, 24, and 48 for data collection. Self-reported adherence was registered at each visit and its veracity was tested by randomized blood analyses performed without previous warning to 40% of patients. Appropriate adherence was defined as the consumption of >/=95% of medication prescribed. Statistical analyses were performed both by the as treated (AT) and the intention to treat missing = failure (ITT) methods. RESULTS: In all, 116 patients were included. At week 48, 94% of patients in the EG versus 69% controls achieved adherence >/=95% (p =.008); 89% of patients in the EG versus 66% controls had HIV-1 RNA levels <400 copies/ml (p =.026). Overall, 85% of patients with adherence >/=95% but only 45% of those with adherence <95% had viral load (VL) <400 copies/ml (p =. 008). In multivariate analysis, variables significantly related to adherence were having received a psychoeducative intervention (odds ratio [OR], 6.58; p =.04), poor effort to take medication (OR, 5.38; p =.03), and high self-perceived capacity to follow the regimen (OR, 13.76; p =.04). Self-reported adherence and drug plasma levels coincided in 93% of cases. However, differences in adherence did not reach statistical significance in the ITT analysis although a clear tendency toward benefit was observed in EG. CONCLUSIONS: Specific and maintained psychoeducative interventions based on excellence on clinical practice are useful to keep high levels of adherence as well as high levels of viral suppression. There is a clear relation between high adherence levels and virologic success. Assessment of certain specific variables related to adherence may be helpful to monitor patient's compliance in the clinical setting.


Asunto(s)
Terapia Antirretroviral Altamente Activa/psicología , Medicina de la Conducta/métodos , Infecciones por VIH/tratamiento farmacológico , Cooperación del Paciente/psicología , Educación del Paciente como Asunto , Adulto , Análisis de Varianza , Femenino , Inhibidores de la Proteasa del VIH/sangre , VIH-1 , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , ARN Viral/sangre , Carga Viral
18.
Bone Marrow Transplant ; 21 Suppl 2: S68-71, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9630331

RESUMEN

A quality-of-life questionnaire study was administered in a group of 98 disease-free survivors more than 3 years after BMT. All participants were over the age of 17 years at the time of the survey. The transplants were performed between 1981 and 1993 in eight Spanish hospitals. Eighty-three percent of patients had undergone BMT for neoplastic disease. Seventy-three per cent received an allogeneic bone marrow transplantation. A modified version of a questionnaire applied in Stanford Hospital to evaluate quality of life in adults after BMT was used. A single investigator was responsible for interviewing all subjects by telephone. We compare these results with the same questionnaire applied in a control group of 58 healthy subjects of similar age. The most significant results were: BMT patients valued their quality of life more highly than the control group. The mean score for global quality of life was 8.19+/-0.17 in BMT group as compared to 7.54+/-0.13 in control group (P=0.0013). Studies were cited as the major concern in both groups: 24% in BMT group and in 69% in control group (C.I. 95%=0.59 to 0.30). The patients in the BMT group considered they had fewer problems in comparison with the control group regarding interpersonal relationships with family members and friends, sleep, depression and leisure possibilities. However, they considered they had more problems concerning their physical appearance, studies and work possibilities than their peers. Considerations regarding weight, height, sexual functioning, anxiety, tendency to suffer illness and problems with insurance were similar in both groups.


Asunto(s)
Trasplante de Médula Ósea/psicología , Calidad de Vida , Adolescente , Adulto , Femenino , Humanos , Relaciones Interpersonales , Masculino
20.
Early Hum Dev ; 53 Suppl: S3-13, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10102650

RESUMEN

Many controversial topics have still to be resolved regarding the nutritional requirements of the newborn, and in particular of the pre-term infant. The term 'controversy' bears the connotation of prolonged dispute and such a situation has arisen for various reasons: (a) from inadequate research methodologies; (b) from the misinterpretation of, or bias within, the results of studies undertaken; (c) from not taking into account the multifactorial etiology of physiopathological situations or illnesses suffered by suckling neonates and newborn infants. Nevertheless, controversy as such is not always a negative factor, as investigation and discussion enable advances in therapeutic methods.


Asunto(s)
Fenómenos Fisiológicos Nutricionales del Lactante , Recien Nacido Prematuro , Necesidades Nutricionales , Carbohidratos de la Dieta/administración & dosificación , Grasas de la Dieta/administración & dosificación , Proteínas en la Dieta/administración & dosificación , Ingestión de Energía , Humanos , Recién Nacido , Minerales/administración & dosificación , Vitaminas/administración & dosificación , Agua
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA