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1.
Nature ; 504(7478): 119-21, 2013 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-24305162

RESUMEN

After the initial burst of γ-rays that defines a γ-ray burst (GRB), expanding ejecta collide with the circumburst medium and begin to decelerate at the onset of the afterglow, during which a forward shock travels outwards and a reverse shock propagates backwards into the oncoming collimated flow, or 'jet'. Light from the reverse shock should be highly polarized if the jet's magnetic field is globally ordered and advected from the central engine, with a position angle that is predicted to remain stable in magnetized baryonic jet models or vary randomly with time if the field is produced locally by plasma or magnetohydrodynamic instabilities. Degrees of linear polarization of P ≈ 10 per cent in the optical band have previously been detected in the early afterglow, but the lack of temporal measurements prevented definitive tests of competing jet models. Hours to days after the γ-ray burst, polarization levels are low (P < 4 per cent), when emission from the shocked ambient medium dominates. Here we report the detection of P =28(+4)(-4) per cent in the immediate afterglow of Swift γ-ray burst GRB 120308A, four minutes after its discovery in the γ-ray band, decreasing to P = 16(+5)(-4) per cent over the subsequent ten minutes. The polarization position angle remains stable, changing by no more than 15 degrees over this time, with a possible trend suggesting gradual rotation and ruling out plasma or magnetohydrodynamic instabilities. Instead, the polarization properties show that GRBs contain magnetized baryonic jets with large-scale uniform fields that can survive long after the initial explosion.

2.
Vox Sang ; 112(4): 336-342, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28321880

RESUMEN

BACKGROUND: There have been recurrent shortages of group O blood due to insufficient inventory and use of group O blood in ABO non-identical recipients. We performed a 12-year retrospective study to determine utilization of group O Rh-positive and Rh-negative red blood cells (RBCs) by recipient ABO group. Reasons for transfusing group O blood to ABO non-identical recipients were also assessed. METHODS: Utilization data from all group O Rh-positive and Rh-negative RBCs transfused at three academic hospitals between April 2002 and March 2014 were included. Data were extracted from Transfusion Registry for Utilization Surveillance and Tracking, a comprehensive database with inventory information on all blood products received at the hospitals. Extracted data included product type, ABO and Rh, final disposition (transfused, wasted, outdated), and demographic and clinical data on all patients admitted to hospital. Descriptive statistics were performed using sas 9.3. RESULTS: There were 314 968 RBC transfusions: 151 645 (48·1%) were group O, of which 138 136 (91·1%) RBC units were transfused to group O individuals. ABO non-identical recipients received 13 509 group O RBCs (8·9%). The percentage of group O RBCs transfused to ABO non-identical recipients by fiscal year varied from 7·8% to 11·1% with a steady increase from 2011 to 2013. Reasons for this included: trauma, outdating, outpatient usage and shortages. CONCLUSION: The practice of transfusing O RBCs to non-O individuals has been increasing. Specific hospital and blood supplier policies could be targeted to change practice, leading to a more sustainable group O red blood cell supply.


Asunto(s)
Sistema del Grupo Sanguíneo ABO , Transfusión de Eritrocitos/estadística & datos numéricos , Sistema del Grupo Sanguíneo Rh-Hr , Adolescente , Adulto , Transfusión de Eritrocitos/tendencias , Femenino , Hospitales , Humanos , Masculino , Estudios Retrospectivos , Adulto Joven
3.
Vox Sang ; 111(3): 299-307, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27231826

RESUMEN

BACKGROUND & OBJECTIVES: Alloimmunization rates following red blood cell (RBC) transfusion in paediatric oncology are not known. This study aimed to: (1) describe frequency and specificity of alloantibodies in paediatric oncology patients after RBC transfusions; (2) determine the effect of chemotherapy on alloimmunization rate. MATERIALS & METHODS: Retrospective cohort study of paediatric patients at a tertiary care hospital is evaluated by two groups: control group, paediatric patients without cancer; study group, paediatric oncology patients who received chemotherapy. Alloimmunization was defined as clinically significant IgG alloantibody formation against RBC antigens. RESULTS: A total of 1273 children were evaluated including 324 in study group, 909 controls, and 40 haemoglobinopathy patients. Overall, frequency of alloimmunization was 1·5%: 0·3% (95% CI: 0, 1·90) in study group; 1·3% (95% CI: 0·73, 2·32) in control group and 15% in haemoglobinopathies. The association between chemotherapy and alloimmunization was not significant; P value = 0·20 Fisher's exact test, OR 0·23 (95% CI: 0·03, 1·79). CONCLUSION: This is the first study exploring RBC alloimmunization in paediatric patients by diagnosis. Alloimmunization frequency was low. It was not possible to determine an association between chemotherapy and alloimmunization due to the low event rate.


Asunto(s)
Transfusión de Eritrocitos/efectos adversos , Eritrocitos/inmunología , Hipersensibilidad/etiología , Adolescente , Antineoplásicos/uso terapéutico , Estudios de Casos y Controles , Niño , Preescolar , Estudios de Cohortes , Femenino , Trasplante de Células Madre Hematopoyéticas , Hemoglobinopatías/terapia , Humanos , Lactante , Isoanticuerpos/sangre , Masculino , Neoplasias/tratamiento farmacológico , Estudios Retrospectivos , Centros de Atención Terciaria
4.
Vox Sang ; 108(3): 274-80, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25556889

RESUMEN

BACKGROUND: Prothrombin complex concentrates (PCCs) can be used instead of frozen plasma (FP) transfusion to reverse the effect of warfarin. Audits have demonstrated over usage of FP transfusions even before the introduction of PCC. The objective of this study was to determine the appropriateness of current FP transfusion practice in the current era since the introduction of PCCs. METHODS: A retrospective cohort study of consecutive patients receiving FP over 3 months was carried out. Each episode of FP use over a 24-h period was adjudicated independently by two reviewers as appropriate (consistent with Canadian/AABB guidelines), appropriate but inconsistent with guidelines or inappropriate. Discrepancies were resolved by a third reviewer. Use of FP to reverse warfarin was considered inappropriate. FP usage from previous years was assessed as baseline. RESULTS: During the study period, 111 FP transfusions were administered. 74.8% of FP usage occurred in the ICU. The proportion of FP transfusions that were deemed appropriate, inconsistent yet appropriate or inappropriate were 33/89 (37.1%), 16/89 (18.0%) and 40/89 (44.9%), respectively, when use of FP for therapeutic plasma exchange was excluded. The most common reasons for inappropriate use were the absence of bleeding with an increased INR or warfarin reversal. CONCLUSION: Our study is the first to audit FP transfusions in the post-PCC era in Canada. FP usage remains inappropriately high in INR prolongation without another indication or to reverse warfarin. Targeted interventions to reduce FP usage in the future should focus on the ICU and on education about warfarin reversal.


Asunto(s)
Factores de Coagulación Sanguínea/efectos adversos , Transfusión de Componentes Sanguíneos/métodos , Plasma , Adulto , Anciano , Anciano de 80 o más Años , Factores de Coagulación Sanguínea/uso terapéutico , Transfusión de Componentes Sanguíneos/normas , Transfusión de Componentes Sanguíneos/estadística & datos numéricos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
5.
J Hypertens ; 27(1): 69-75, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19145770

RESUMEN

OBJECTIVE: To examine in a population with a high prevalence of hypertension, the association between six cardiovascular polymorphisms, arterial stiffness and medication use. METHODS: In this cross-sectional study (Hypertension: Interaction and Prevalence of POlymorphisms related to Cardiovascular Risk and the Association to Treatment Efficacy Study project), arterial stiffness was assessed by measuring pulse wave velocity (PWV) in 575 patients in one primary care practice. Patients were genotyped for the angiotensin II type 1 receptor [AGTR1 (A1166C)], angiotensinogen (M235T), angiotensin-converting enzyme (4656rpt), endothelial nitric oxide synthase (E298D), G-protein beta3 (C825T), and alpha-adducin (G460W) polymorphisms. Linear regression analyses were performed to assess the association between polymorphisms and PWV. RESULTS: Thirty percent of the patients (273 men, 302 women) had a carotid-femoral pulse wave velocity above 12 m/s and more than 60% of the patients had a carotid-femoral/carotid-radial PWV (CF/CR ratio) above 1. The CF/CR ratio was significantly associated with age, sex, dislipidemia, cardiovascular medication use and pulse pressure. After correction for these covariates, multivariate linear regression analyses showed that the C allele of AGTR1 was associated with a lower CF/CR ratio. This association was significantly influenced by cardiovascular medication use (P = 0.011), and showed a dose-allele effect, the CF/CR ratio decreasing with the number of C alleles (P = 0.04). CONCLUSION: In a primary care population, this study showed an independent protective dose-allele effect for the presence of C alleles of the AGTR1 polymorphism on PWV. This association, which was influenced by the use of cardiovascular medication, needs further investigations to identify the underlying mechanisms.


Asunto(s)
Fármacos Cardiovasculares/uso terapéutico , Arterias Carótidas/fisiología , Arteria Femoral/fisiología , Polimorfismo Genético , Arteria Radial/fisiología , Receptor de Angiotensina Tipo 1/genética , Anciano , Velocidad del Flujo Sanguíneo , Estudios Transversales , Femenino , Frecuencia de los Genes , Humanos , Masculino , Persona de Mediana Edad
6.
Arch Orthop Trauma Surg ; 129(2): 259-65, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18488236

RESUMEN

INTRODUCTION: Whether to resurface the patella or not in total knee arthroplasty still remains undecided. Classical scores and questionnaires might not be responsive or demanding enough. This study used two accelerometer based systems to study the hypothesis whether performance based tests are able to detect a difference in patients with or without a resurfaced patella. METHOD: In this retrospective study 53 patients were included and divided into a resurfaced group (n = 31) and a non-resurfaced group (n = 22). Both groups were matched on age and longevity of follow up. Patients were clinically assessed using the Knee Society Score (KSS) at various time points. At final follow up patients were also assessed once using the Dynaport Knee Test and the Minimod Gait Test. RESULTS: The Dynaport Knee Test showed a significant functional advantage for patients with a resurfaced patella [44 vs. 39.7 (P = 0.042)], whereas KSS and The Minimod were not significant (P values ranging from 0.07 to 0.75). Similar to other reports in literature, using the KSS, it was not possible to identify significant difference between patella resurfacing or retaining in total knee arthroplasty, however using a performance based test it was possible to determine significant difference. The found advantage of patella resurfacing may be less due to pain relief but due to a functional benefit during demanding motion tasks. This finding indicates that current measurement tools may not be accurate or specific enough to detect this difference. Therefore, we recommend complementing the classic evaluation tools with an objective functional test, when conducting a randomized trial to answer the indecision whether to resurface the patella or not.


Asunto(s)
Artroplastia de Reemplazo de Rodilla/métodos , Osteoartritis de la Rodilla/cirugía , Rótula/cirugía , Anciano , Humanos , Recuperación de la Función , Estudios Retrospectivos , Resultado del Tratamiento
7.
Carcinogenesis ; 29(9): 1765-73, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18339680

RESUMEN

Intake of dietary factors that serve as methyl group donors may influence promoter hypermethylation in colorectal carcinogenesis. We investigated whether dietary folate, vitamin B2 and vitamin B6, methionine and alcohol were associated with mutL homologue 1 (MLH1) hypermethylation and the related molecular phenotypes of MLH1 protein expression, microsatellite instability (MSI) and BRAF mutations in patients with colorectal carcinomas. Within the Netherlands Cohort Study on diet and cancer (n = 120 852), 648 cases (367 men and 281 women) and 4059 subcohort members were available for data analyses from a follow-up period between 2.3 and 7.3 years after baseline. Gender-specific adjusted incidence rate ratios (RRs) were calculated over categories of dietary intake in case-cohort analyses. The intakes of folate, vitamin B2, methionine and alcohol were not associated with risk of tumors showing MLH1 hypermethylation, those lacking MLH1 protein expression or with MSI. Among men, we observed strong positive associations between folate and BRAF-mutated tumors (RR = 3.04 for the highest versus lowest tertile of intake, P(trend) = 0.03) and between vitamin B6 and tumors showing MLH1 hypermethylation (highest versus lowest tertile: RR = 3.23, P(trend) = 0.03). Among women, the relative risks of tumors with BRAF mutations or MLH1 hypermethylation were also increased in the highest tertiles of folate and vitamin B6 intake, respectively, but these did not reach statistical significance. The positive associations between folate intake and tumors harboring BRAF mutations and between vitamin B6 intake and those showing MLH1 hypermethylation were most pronounced among men and may suggest that these vitamins enhance colorectal cancer risk through genetic as well as epigenetic aberrations.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Neoplasias Colorrectales/genética , Metilación de ADN , Dieta , Metionina/administración & dosificación , Proteínas Nucleares/genética , Regiones Promotoras Genéticas/genética , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Anciano , Estudios de Cohortes , Neoplasias Colorrectales/epidemiología , Neoplasias Colorrectales/metabolismo , ADN de Neoplasias/genética , ADN de Neoplasias/metabolismo , Femenino , Ácido Fólico/administración & dosificación , Humanos , Masculino , Repeticiones de Microsatélite , Persona de Mediana Edad , Homólogo 1 de la Proteína MutL , Mutación/genética , Países Bajos/epidemiología , Proteínas Nucleares/metabolismo , Fenotipo , Proteínas Proto-Oncogénicas B-raf/metabolismo , Riboflavina/administración & dosificación , Encuestas y Cuestionarios , Vitamina B 12/administración & dosificación , Vitamina B 6/administración & dosificación
8.
J Am Coll Nutr ; 27(1): 117-26, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18460490

RESUMEN

OBJECTIVE: Baseline characteristics of subjects might be related to the effect of plant stanols on the serum lipoprotein profile. The aim of the study was to examine effects of subjects' baseline characteristics (baseline serum concentrations of lipids and lipoproteins at the start of the study, lathosterol, campesterol and sitosterol; gender, age, BMI, smoking, use of oral contraceptives and menopause) on the effects of plant stanol esters on the serum lipoprotein profile. METHODS: We used data of five studies performed at our Department. A random intercept model was used for statistical analysis, using serum lipid and lipoprotein concentrations after plant stanol ester consumption, as dependent variables. RESULTS: After plant stanol ester consumption, higher baseline serum concentrations of total and LDL cholesterol resulted in larger absolute decreases in their respective serum concentrations. For the ratio of total to HDL cholesterol and triacylglycerol, higher baseline serum levels resulted in larger absolute and relative decreases in their serum levels. HDL cholesterol concentrations increased in subjects with low baseline concentrations and decreased in those with high baseline concentrations. Effects however were small. No relationships were observed with baseline serum cholesterol-standardized lathosterol and campesterol concentrations, although LDL cholesterol concentrations tended to decrease more at higher baseline sitosterol concentrations. No effects of other baseline characteristics were found. CONCLUSIONS: People with an unfavorable serum lipid and lipoprotein profile benefit even more of plant stanols than people with a more favorable profile.


Asunto(s)
Anticolesterolemiantes/administración & dosificación , Colesterol/sangre , Lipoproteínas/sangre , Sitoesteroles/administración & dosificación , Triglicéridos/sangre , Adulto , Anticolesterolemiantes/farmacología , Femenino , Humanos , Masculino , Metaanálisis como Asunto , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto , Sitoesteroles/farmacología , Resultado del Tratamiento
9.
Alcohol Clin Exp Res ; 32(4): 645-51, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18241313

RESUMEN

BACKGROUND: Current alcohol intake has been associated with cardiovascular morbidity and mortality. The effect of past and lifetime drinking has received less attention. In the present study, the impact of current, past and lifetime drinking on cardiovascular events and all-cause mortality has been assessed. Secondly, the effect of accounting for covariates within these relationships has been studied. METHODS: The Lifestyle and Health study is a prospective cohort study in 2 regions of the Netherlands. Men and women aged 45 to 70 years registered in 34 general practices were followed over the period July 1996 to June 2001. At baseline, an extensive questionnaire had to be filled in. It included 3 questionnaires about alcohol intake: a Weekly Recall, a Quantity-Frequency about last year, and the Lifetime Drinking History questionnaire. Health problems were registered by the general practitioners. RESULTS: During follow-up, 679 men and 397 women had a cardiovascular event and 330 men and 204 women died. Current drinking was associated with lower risks of cardiovascular events (women) and all-cause mortality (men and women) compared with never drinkers. The relationships were strongest for alcohol intake measured with the Weekly Recall. Lifetime alcohol intake and alcohol intake in the distant past did not seem to be related to all-cause mortality or cardiovascular events. Adjustments for covariates weakened the relationships. CONCLUSIONS: Potential positive effects of drinking seem to be of a transient nature, as lifetime drinking and drinking in the past could not be related to all-cause mortality or cardiovascular events. The alleged benefits of current drinking at baseline diminished with increasing methodological quality and rigor.


Asunto(s)
Consumo de Bebidas Alcohólicas/mortalidad , Enfermedades Cardiovasculares/mortalidad , Estilo de Vida , Adolescente , Adulto , Anciano , Consumo de Bebidas Alcohólicas/efectos adversos , Bebidas Alcohólicas/efectos adversos , Enfermedades Cardiovasculares/etiología , Niño , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Mortalidad/tendencias , Países Bajos/epidemiología , Estudios Prospectivos , Factores de Riesgo , Encuestas y Cuestionarios
10.
J Thromb Haemost ; 16(7): 1402-1412, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29723924

RESUMEN

Essentials The immunogenesis of Heparin-induced thrombocytopenia (HIT) is not well understood. Immunization to platelet factor 4 (PF4)-heparin occurs early in life, before any heparin exposure. PF4 and PF4-heparin complexes induce the proliferation of CD14+ cells. Reduced levels of regulatory cytokines contribute to immune dysregulation in HIT. SUMMARY: Background Heparin-induced thrombocytopenia (HIT) is an adverse reaction to heparin characterized by thrombocytopenia and thrombotic complications. HIT is caused by pathogenic antibodies that bind to complexes of platelet factor 4 (PF4) and heparin, leading to platelet activation and inducing a hypercoagulable state. Previous studies have shown immunity to PF4-heparin complexes occurs early in life, even before heparin exposure; however, the immunogenesis of HIT is not well characterized. Objectives To investigate cellular proliferation in response to PF4-heparin complexes in patients with HIT. Patients/Methods Peripheral blood mononuclear cells (PBMCs) from healthy controls (n = 30), postoperative cardiac surgery patients who had undergone cardiopulmonary bypass (CPB) (n = 17) and patients with confirmed HIT (n = 41) were cultured with PF4 and PF4-heparin complexes. Cellular proliferation was assessed by [3 H]thymidine uptake and 5-ethynyl-2'-deoxyuridine detection. Results and Conclusions PBMCs proliferated in the presence of PF4, and this was enhanced by the addition of heparin in all study groups. CPB and HIT patients showed significantly greater proliferative responses than healthy controls. PBMC proliferation was antigen-specific, depended on the presence of platelets, and only CD14+ cells were identified as proliferating cells. Culture supernatants were tested for the levels of regulatory cytokines, and both CPB and HIT patients produced significantly lower levels of interleukin-10 and transforming growth factor-ß1 than healthy controls. These findings further demonstrate cellular immune sensitization to PF4-heparin complexes occurs before heparin exposure, and suggests immune dysregulation can contribute to HIT.


Asunto(s)
Anticoagulantes/efectos adversos , Anticoagulantes/inmunología , Proliferación Celular , Heparina/efectos adversos , Heparina/inmunología , Inmunidad Celular , Leucocitos Mononucleares/inmunología , Factor Plaquetario 4/inmunología , Trombocitopenia/inducido químicamente , Trombocitopenia/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Células Cultivadas , Femenino , Humanos , Interleucina-10/sangre , Interleucina-10/inmunología , Leucocitos Mononucleares/metabolismo , Receptores de Lipopolisacáridos/sangre , Receptores de Lipopolisacáridos/inmunología , Masculino , Persona de Mediana Edad , Factor Plaquetario 4/sangre , Trombocitopenia/sangre , Factor de Crecimiento Transformador beta1/sangre , Factor de Crecimiento Transformador beta1/inmunología , Adulto Joven
11.
J Clin Endocrinol Metab ; 92(4): 1409-14, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17264187

RESUMEN

CONTEXT: Childhood obesity is now considered to be an epidemic. Drug therapy in this age group remains a topic of research. OBJECTIVE: The objective of this study was to examine the effect of treatment with sibutramine (10 mg) on body composition and energy expenditure in obese adolescents. DESIGN: The study was conducted as a randomized, double-blind, placebo-controlled trial. SETTING: The study was set in an obesity research center. PATIENTS: The patients were 24 obese adolescents (age 12-17 yr, 11 boys); four patients withdrew. INTERVENTION: Intervention was sibutramine (Meridia) or placebo in combination with an energy-restricted diet and exercise plan for 12 wk, followed by an identical, but medication-free, treatment period (follow-up). MAIN OUTCOME MEASURE: Change in body mass index (BMI) sd score (BMI-SDS) was the principal measure of efficacy. Body composition and total energy expenditure were measured by stable isotopes and further calculated according to the four-component model, using underwater weighing and dual x-ray absorptiometry. Basal metabolic rate (BMR) was measured by ventilated hood and adjusted for sex and body composition (BMRadj). RESULTS: After intervention, the decrease in BMI-SDS was comparable in both groups. During follow-up, BMI further decreased in the placebo group but stabilized in the sibutramine group. Changes in the percentage of fat mass were not different between both groups. BMRadj decreased in the placebo group and remained constant in the sibutramine group. During follow-up, BMRadj decreased in the sibutramine group and increased in the placebo group. Changes in total energy expenditure were not significantly different. CONCLUSION: The effect of sibutramine on BMI-SDS was not significant. Sibutramine may diminish the decrease in BMRadj associated with energy restriction in obese adolescents.


Asunto(s)
Depresores del Apetito/uso terapéutico , Composición Corporal/efectos de los fármacos , Ciclobutanos/uso terapéutico , Metabolismo Energético/efectos de los fármacos , Obesidad/fisiopatología , Adolescente , Determinación de la Edad por el Esqueleto , Presión Sanguínea , Estatura/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Método Doble Ciego , Femenino , Frecuencia Cardíaca , Humanos , Masculino , Obesidad/tratamiento farmacológico , Placebos
12.
Br J Gen Pract ; 57(536): 184-90, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17359604

RESUMEN

BACKGROUND: The efficacy of bed covers that are impermeable to house dust mites has been disputed. AIM: The aim of the present study was to investigate whether the combination of 'house dust mite impermeable' covers and a self-management plan, based on peak flow values and symptoms, leads to reduced use of inhaled corticosteroids (ICS) than self-management alone. DESIGN OF STUDY: Prospective, randomised, double blind, placebo-controlled trial. SETTING: Primary care in a south-eastern region of the Netherlands. METHOD: Asthma patients aged between 16 and 60 years with a house dust mite allergy requiring ICS were randomised to intervention and placebo groups. They were trained to use a self-management plan based on peak flow and symptoms. After a 3-month training period, the intervention commenced using house dust mite impermeable and placebo bed covers. The follow-up period was 2 years. Primary outcome was the use of ICS; secondary outcomes were peak expiratory flow parameters, asthma control, and symptoms. RESULTS: One hundred and twenty-six patients started the intervention with house dust mite impermeable or placebo bed covers. After 1 and 2 years, significant differences in allergen exposure were found between the intervention and control groups (P<0.001). No significant difference between the intervention and control groups was found in the dose of ICS (P = 0.08), morning peak flow (P = 0.52), peak flow variability (P = 0.36), dyspnoea (P = 0.46), wheezing (P = 0.77), or coughing (P = 0.41). There was no difference in asthma control between the intervention and control groups. CONCLUSION: House dust mite impermeable bed covers combined with self-management do not lead to reduced use of ICS compared with self-management alone.


Asunto(s)
Corticoesteroides/administración & dosificación , Asma/prevención & control , Pyroglyphidae , Control de Ácaros y Garrapatas/métodos , Adolescente , Adulto , Animales , Asma/tratamiento farmacológico , Ropa de Cama y Ropa Blanca/parasitología , Ropa de Cama y Ropa Blanca/normas , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Países Bajos , Ápice del Flujo Espiratorio , Estudios Prospectivos , Autoadministración , Resultado del Tratamiento
13.
Am J Health Behav ; 31(2): 135-45, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17269904

RESUMEN

OBJECTIVES: To examine psychosocial predictors of changes in fruit and vegetable consumption. METHODS: Baseline psychosocial variables were used to explain differences in changes in consumption in 83 healthy women with children after they received free fruit and vegetables for one month. RESULTS: One-month changes in fruit consumption (mean 144; SE 16 g/day) were positively associated with perceived costs and perceived health benefits for the children, and negatively associated with perceived behavioral control. Changes in vegetable consumption (68 (11) g/day) were positively related with the intention to eat at least 200 g of vegetables and taste preferences of the children. CONCLUSIONS: Fruit and vegetable consumption may be encouraged by influencing the above variables.


Asunto(s)
Preferencias Alimentarias/psicología , Frutas , Verduras , Niño , Femenino , Predicción , Conductas Relacionadas con la Salud , Promoción de la Salud , Humanos , Estudios Longitudinales , Países Bajos , Encuestas y Cuestionarios
14.
Pflege Z ; 60(11): 620-5, 2007 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-18062627

RESUMEN

A large number of breast cancer patients receiving adjuvant chemotherapy is suffering from fatigue. Until now there has been a lack of knowledge concerning the course of fatigue in breast cancer patients between two cycles of adjuvant chemotherapy. Therefore a prospective cohort study was conducted including 151 breast cancer patients from six hospitals in The Netherlands. The object of the study was to investigate the course of fatigue between the third and the fourth cycles of adjuvant chemotherapy, and to prove whether that course is influenced by different chemotherapy schedules. The patients were treated either with a doxorubicin containing schedule (21 or 28 days) or with a combination of cyclophosphamide, methotrexate, and 5-fluorouracil (CMF, 28 days). To assess fatigue patients were asked to write a diary cotaining the Shortened Fatigue Questionnaire (SFQ) from the beginning of the third cycle to the start of the fourth one. All days after completion of the third chemotherapy treatment were analysed. The main hypothesis to be tested was that the maximum fatigue level occurs in the first four days after treatment. Results revealed a chaotic pattern of fatigue between both cycles of chemotherapy in each of the treatment group. Smooth (splines) curves showed an average highest level of fatigue on day 3 post treatment. For the regimens with 28-days-intervalls another peak of fatigue was registered on day 11. A significant larger number of patients experienced maximum fatigue levels before day 5. The course of fatigue in the CMF group was significantly different compared with both doxorubicin groups. Women of the CMF group experienced lower fatigue peaks than patients of other groups. The results confirm the main hypothesis. The first days after treatment with chemotherapy are the worst ones for breast cancer patients. The course of fatigue is significantly related to the type of chemotherapy. Knowing these effects patients can better prepare oneself and their daily living for the time of adjuvant chemotherapy.


Asunto(s)
Neoplasias de la Mama/enfermería , Quimioterapia Adyuvante/enfermería , Fatiga/enfermería , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias de la Mama/tratamiento farmacológico , Quimioterapia Adyuvante/efectos adversos , Investigación en Enfermería Clínica , Estudios de Cohortes , Ciclofosfamida/administración & dosificación , Ciclofosfamida/efectos adversos , Doxorrubicina/administración & dosificación , Doxorrubicina/efectos adversos , Esquema de Medicación , Fatiga/inducido químicamente , Femenino , Fluorouracilo/administración & dosificación , Fluorouracilo/efectos adversos , Humanos , Metotrexato/administración & dosificación , Metotrexato/efectos adversos , Persona de Mediana Edad , Países Bajos
15.
Am J Clin Nutr ; 84(4): 717-24, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17023696

RESUMEN

BACKGROUND: To improve the effective prevention and treatment of obesity, it is important to focus on body weight (BW) development and its determinants during childhood. OBJECTIVE: The aim of the present study was to investigate the effects of early development, parental and genetic variables, and behavioral determinants on overweight at 12 y. DESIGN: In a Dutch cohort of 105 children, anthropometric measurements were conducted from birth until age 7 y. At age 12 y, anthropometric measurements were obtained again, as were measurements of body composition, leptin concentration, 3 polymorphisms, and physical activity, and the Three-Factor Eating Questionnaire was conducted. In addition, parental body mass indexes (BMIs, in kg/m2) and Three-Factor Eating Questionnaire scores were determined. RESULTS: The children's mean (+/-SD) BMI at 12 y was 19.0 +/- 2.6, and 15.2% were classified as overweight. From the first year of life, BMI tracked significantly with BMI at age 12 y (r = 0.24, P < 0.05). Linear regression analyses showed that a rapid increase in BW during the first year of life, a high BMI of the father, and a high dietary restraint score of the mother were significantly associated with overweight at age 12 y (P < 0.05). No significant genetic relation was observed. In addition, overweight was positively associated with dietary restraint of the child, and percentage body fat was negatively associated with the child's activity score (P < 0.05). CONCLUSIONS: In this homogeneous cohort of normal-weight to moderately overweight children, tracking of BMI during childhood took place from the first year of life. Overweight at age 12 y was predicted by an early rapid increase in BW and parental influences. Overweight during childhood may be maintained or even promoted by a high dietary restraint score and low physical activity.


Asunto(s)
Obesidad/prevención & control , Sobrepeso , Composición Corporal , Índice de Masa Corporal , Niño , Preescolar , Estudios de Cohortes , Conducta Alimentaria , Femenino , Genotipo , Humanos , Lactante , Recién Nacido , Leptina/sangre , Modelos Lineales , Masculino , Actividad Motora , Países Bajos/epidemiología , Obesidad/epidemiología , Obesidad/etiología , Sobrepeso/genética , Padres , Esfuerzo Físico , Polimorfismo Genético , Valor Predictivo de las Pruebas , Factores de Riesgo , Encuestas y Cuestionarios
16.
BMC Med ; 4: 24, 2006 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-17029622

RESUMEN

BACKGROUND: Many risk factors for fractures have been documented, including low bone-mineral density (BMD) and a history of fractures. However, little is known about the short-term absolute risk (AR) of fractures and the timing of clinical fractures. Therefore, we assessed the risk and timing of incident clinical fractures, expressed as 5-year AR, in postmenopausal women. METHODS: In total, 10 general practice centres participated in this population-based prospective study. Five years after a baseline assessment, which included clinical risk factor evaluation and BMD measurement, 759 postmenopausal women aged between 50 and 80 years, were re-examined, including undergoing an evaluation of clinical fractures after menopause. Risk factors for incident fractures at baseline that were significant in univariate analyses were included in a multivariate Cox survival regression analysis. The significant determinants were used to construct algorithms. RESULTS: In the total group, 12.5% (95% confidence interval (CI) 10.1-14.9) of the women experienced a new clinical fracture. A previous clinical fracture after menopause and a low BMD (T-score <-1.0) were retained as significant predictors with significant interaction. Women with a recent previous fracture (during the past 5 years) had an AR of 50.1% (95% CI 42.0-58.1) versus 21.2% (95% CI 20.7-21.6) if the previous fracture had occurred earlier. In women without a fracture history, the AR was 13.8% (95% CI 10.9-16.6) if BMD was low and 7.0% (95% CI 5.5-8.5) if BMD was normal. CONCLUSION: In postmenopausal women, clinical fractures cluster in time. One in two women with a recent clinical fracture had a new clinical fracture within 5 years, regardless of BMD. The 5-year AR for a first clinical fracture was much lower and depended on BMD.


Asunto(s)
Densidad Ósea , Fracturas Óseas/epidemiología , Osteoporosis Posmenopáusica/complicaciones , Anciano , Calcio/administración & dosificación , Café , Femenino , Fracturas Óseas/etiología , Humanos , Persona de Mediana Edad , Análisis Multivariante , Posmenopausia , Modelos de Riesgos Proporcionales , Recurrencia , Factores de Riesgo , Fumar , Encuestas y Cuestionarios , Factores de Tiempo
17.
J Pain ; 7(4): 261-71, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16618470

RESUMEN

UNLABELLED: The aim of this study was to examine whether treatments based on different theories change pain catastrophizing and internal control of pain, and whether changes in these factors mediate treatment outcome. Participants were 211 patients with nonspecific chronic low back pain (CLBP) participating in a randomized controlled trial, attending active physical treatment (APT, n = 52), cognitive-behavioral treatment (CBT, n = 55), treatment combining the APT and CBT (CT, n = 55), or waiting list (WL, n = 49). Pain catastrophizing decreased in all 3 active treatment groups and not in the WL. There was no difference in the change in internal control across all 4 groups. In all the active treatment groups, patients improved regarding perceived disability, main complaints, and current pain at post-treatment, and no changes were observed in the WL group. Depression only changed significantly in the APT group. Change in pain catastrophizing mediated the reduction of disability, main complaints, and pain intensity. In the APT condition, pain catastrophizing also mediated the reduction of depression. Not only cognitive-behavioral treatments but also a physical treatment produced changes in pain catastrophizing that seemed to mediate the outcome of the treatment significantly. The implications and limitations of these results are discussed. PERSPECTIVE: This article shows that treatment elements that do not deliberately target cognitive factors can reduce pain catastrophizing. Reduction in pain catastrophizing seemed to mediate the improvement of functioning in patients with chronic low back pain. The results might contribute to the development of more effective interventions.


Asunto(s)
Adaptación Psicológica , Terapia Cognitivo-Conductual , Ejercicio Físico , Control Interno-Externo , Dolor de la Región Lumbar/psicología , Dolor de la Región Lumbar/terapia , Adulto , Actitud Frente a la Salud , Enfermedad Crónica , Terapia Combinada , Trastorno Depresivo/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
18.
BMC Public Health ; 6: 204, 2006 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-16893463

RESUMEN

BACKGROUND: Little is known about how sexual and reproductive (SRH) health can be made accessible and appropriate to adolescents. This study evaluates the impact and sustainability of a competitive voucher program on the quality of SRH care for poor and underserved female adolescents and the usefulness of the simulated patient (SP) method for such evaluation. METHODS: 28,711 vouchers were distributed to adolescents in disadvantaged areas of Managua that gave free-of-charge access to SRH care in 4 public, 10 non-governmental and 5 private clinics. Providers received training and guidelines, treatment protocols, and financial incentives for each adolescent attended. All clinics were visited by female adolescent SPs requesting contraception. SPs were sent one week before, during (with voucher) and one month after the intervention. After each consultation they were interviewed with a standardized questionnaire. Twenty-one criteria were scored and grouped into four categories. Clinics' scores were compared using non-parametric statistical methods (paired design: before-during and before-after). Also the influence of doctors' characteristics was tested using non-parametric statistical methods. RESULTS: Some aspects of service quality improved during the voucher program. Before the program started 8 of the 16 SPs returned 'empty handed', although all were eligible contraceptive users. During the program 16/17 left with a contraceptive method (p = 0.01). Furthermore, more SPs were involved in the contraceptive method choice (13/17 vs.5/16, p = 0.02). Shared decision-making on contraceptive method as well as condom promotion had significantly increased after the program ended. Female doctors had best scores before- during and after the intervention. The improvements were more pronounced among male doctors and doctors older than 40, though these improvements did not sustain after the program ended. CONCLUSION: This study illustrates provider-related obstacles adolescents often face when requesting contraception. The care provided during the voucher program improved for some important outcomes. The improvements were more pronounced among providers with the weakest initial performance. Shared decision-making and condom promotion were improvements that sustained after the program ended. The SP method is suitable and relatively easy to apply in monitoring clinics' performance, yielding important and relevant information. Objective assessment of change through the SP method is much more complex and expensive.


Asunto(s)
Servicios de Salud del Adolescente/economía , Centros Comunitarios de Salud/economía , Servicios de Planificación Familiar/economía , Áreas de Pobreza , Práctica Privada/economía , Atención no Remunerada , Poblaciones Vulnerables , Adolescente , Servicios de Salud del Adolescente/normas , Adulto , Centros Comunitarios de Salud/normas , Anticonceptivos Femeninos/provisión & distribución , Dispositivos Anticonceptivos Femeninos/provisión & distribución , Competencia Económica , Servicios de Planificación Familiar/normas , Femenino , Accesibilidad a los Servicios de Salud , Humanos , Motivación , Nicaragua , Participación del Paciente , Simulación de Paciente , Relaciones Médico-Paciente , Práctica Privada/normas , Evaluación de Programas y Proyectos de Salud , Garantía de la Calidad de Atención de Salud , Encuestas y Cuestionarios
19.
BMC Musculoskelet Disord ; 7: 5, 2006 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-16426449

RESUMEN

BACKGROUND: The treatment of non-specific chronic low back pain is often based on three different models regarding the development and maintenance of pain and especially functional limitations: the deconditioning model, the cognitive behavioral model and the biopsychosocial model. There is evidence that rehabilitation of patients with chronic low back pain is more effective than no treatment, but information is lacking about the differential effectiveness of different kinds of rehabilitation. A direct comparison of a physical, a cognitive-behavioral treatment and a combination of both has never been carried out so far. METHODS: The effectiveness of active physical, cognitive-behavioral and combined treatment for chronic non-specific low back pain compared with a waiting list control group was determined by performing a randomized controlled trial in three rehabilitation centers. Two hundred and twenty three patients were randomized, using concealed block randomization to one of the following treatments, which they attended three times a week for 10 weeks: Active Physical Treatment (APT), Cognitive-Behavioral Treatment (CBT), Combined Treatment of APT and CBT (CT), or Waiting List (WL). The outcome variables were self-reported functional limitations, patient's main complaints, pain, mood, self-rated treatment effectiveness, treatment satisfaction and physical performance including walking, standing up, reaching forward, stair climbing and lifting. Assessments were carried out by blinded research assistants at baseline and immediately post-treatment. The data were analyzed using the intention-to-treat principle. RESULTS: For 212 patients, data were available for analysis. After treatment, significant reductions were observed in functional limitations, patient's main complaints and pain intensity for all three active treatments compared to the WL. Also, the self-rated treatment effectiveness and satisfaction appeared to be higher in the three active treatments. Several physical performance tasks improved in APT and CT but not in CBT. No clinically relevant differences were found between the CT and APT, or between CT and CBT. CONCLUSION: All three active treatments were effective in comparison to no treatment, but no clinically relevant differences between the combined and the single component treatments were found.


Asunto(s)
Terapia Cognitivo-Conductual , Dolor de la Región Lumbar/rehabilitación , Modalidades de Fisioterapia , Adulto , Enfermedad Crónica , Terapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Encuestas y Cuestionarios , Análisis y Desempeño de Tareas , Resultado del Tratamiento
20.
Am J Clin Nutr ; 82(4): 740-6, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16210701

RESUMEN

BACKGROUND: Genetic variation in the peroxisome proliferator-activated receptor gamma2 (PPARgamma2), glucocorticoid receptor (GRL), and ciliary neurotrophic factor (CNTF) genes may play a role in the etiology of obesity. OBJECTIVE: We examined biological, psychological, and genetic determinants associated with weight maintenance (WM) after weight loss. DESIGN: Subjects (n = 120) followed a 6-wk diet and then a 1-y period of WM. Body weight (BW), body composition, leptin concentration, attitude toward eating (measured with the Three-Factor Eating Questionnaire), physical activity, and the polymorphisms of the PPARgamma2, GRL, and CNTF genes were measured. RESULTS: BW loss was 7.0 +/- 3.1 kg. After 1 y, 21 subjects showed successful WM (<10% regain); 99 were unsuccessful (> or =10% regain). Compared with unsuccessful subjects, successful subjects had a higher increase in dietary restraint over time (4.8 +/- 5.0 and 1.8 +/- 3.9, respectively; P < 0.01) but significantly less sensation of general hunger (-4.0 +/- 4.9 and -1.2 +/- 2.7, respectively; P < 0.05). Successful subjects had a significantly different frequency distribution for the PPARgamma2 (P = 0.05) and GRL (P < 0.05) genes than did unsuccessful subjects. The more successful genotypes showed a higher baseline body mass index and waist circumference (PPARgamma2), a greater decrease in disinhibition of dietary restraint (GRL), and less sensation of hunger (GRL). The G/G genotype (GRL) was an independent predictor of successful WM. CONCLUSION: The different genotypes of the PPARgamma2 and GRL genes contribute to WM, either directly (GRL) or indirectly (PPARgamma2 and GRL) via baseline body mass index and waist circumference, and to changes in Three-Factor Eating Questionnaire scores.


Asunto(s)
Factor Neurotrófico Ciliar/genética , Ingestión de Alimentos/genética , Obesidad/etiología , PPAR gamma/genética , Polimorfismo Genético , Receptores de Glucocorticoides/genética , Adulto , Anciano , Actitud Frente a la Salud , Composición Corporal/fisiología , Restricción Calórica , Factor Neurotrófico Ciliar/fisiología , Dieta Reductora , Ingestión de Alimentos/fisiología , Ingestión de Alimentos/psicología , Ejercicio Físico/fisiología , Femenino , Genotipo , Humanos , Hambre/fisiología , Leptina/sangre , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Obesidad/dietoterapia , Obesidad/genética , Obesidad/psicología , PPAR gamma/fisiología , Cooperación del Paciente , Receptores de Glucocorticoides/fisiología , Encuestas y Cuestionarios , Pérdida de Peso/genética , Pérdida de Peso/fisiología
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