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1.
Diabet Med ; 35(11): 1596-1604, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29999549

RESUMEN

AIM: To investigate the association between cardiovascular autonomic neuropathy and bone metabolism in people with Type 1 diabetes. METHODS: We assessed cardiovascular autonomic neuropathy in 329 people with Type 1 diabetes according to heart rate response to deep breathing, to standing and to the Valsalva manoeuvre, and 2-min resting heart rate. More than one pathological non-resting test was defined as cardiovascular autonomic neuropathy. Bone mineral density of the femoral neck (BMDfn) was assessed by dual energy X-ray absorptiometry. Serum parathyroid hormone levels and other bone markers were measured. RESULTS: The mean (sd) age of the participants was 55.6 (9.4) years, 52% were men, and the mean (sd) diabetes duration was 40 (8.9) years, HbA1c 62 (9) mmol/mol and estimated GFR 78 (26) ml/min/1.73m2 . In all, 36% had cardiovascular autonomic neuropathy. Participants with cardiovascular autonomic neuropathy had 4.2% (95% CI -8.0 to -0.2; P=0.038) lower BMDfn and 33.6% (95% CI 14.3 to 53.8; P=0.0002) higher parathyroid hormone levels compared with participants without cardiovascular autonomic neuropathy in adjusted models. Higher resting heart rate remained associated with higher parathyroid hormone level and lower BMDfn after additional adjustment for eGFR (P<0.0001 and P = 0.042, respectively). CONCLUSIONS: The presence of cardiovascular autonomic neuropathy was associated with reduced BMDfn and increased levels of parathyroid hormone. Kidney function may either confound or mediate these findings. Cardiovascular autonomic neuropathy could be associated with increased risk of osteoporosis in Type 1 diabetes. Whether cardiovascular autonomic neuropathy directly affects bone metabolism detrimentally or if this association is mediated via decreased kidney function should be investigated further.


Asunto(s)
Enfermedades del Sistema Nervioso Autónomo/epidemiología , Huesos/metabolismo , Enfermedades Cardiovasculares/epidemiología , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/epidemiología , Angiopatías Diabéticas/epidemiología , Osteoporosis/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Enfermedades del Sistema Nervioso Autónomo/complicaciones , Densidad Ósea , Enfermedades Cardiovasculares/complicaciones , Estudios de Casos y Controles , Estudios Transversales , Angiopatías Diabéticas/complicaciones , Angiopatías Diabéticas/metabolismo , Neuropatías Diabéticas/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteoporosis/etiología , Osteoporosis/metabolismo , Factores de Riesgo , Adulto Joven
2.
J Perinatol ; 37(2): 208-213, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27735929

RESUMEN

OBJECTIVE: Ethically and legally, assertions that resuscitation is in a patient's best interest should be inversely correlated with willingness to forego intensive care (and accept comfort care) at the surrogate's request. Previous single country studies have demonstrated a relative devaluation of neonates when compared with other critically ill patients. STUDY DESIGN: In this international study, physicians in Argentina, Australia, Canada, Ireland, The Netherlands, Norway and the United States were presented with eight hypothetical vignettes of incompetent critically ill patients of different ages. They were asked to make assessments about best interest, respect for surrogate autonomy and to rank the patients in a triage scenario. RESULTS: In total, 2237 physicians responded (average response rate 61%). In all countries and scenarios, participants did not accept to withhold resuscitation if they estimated it was in the patient's best interest, except for scenarios involving neonates. Young children (other than neonates) were given high priority for resuscitation, regardless of existing disability. For neonates, surrogate autonomy outweighed assessment of best interest. In all countries, a 2-month-old-infant with meningitis and a multiply disabled 7-year old were resuscitated first in the triage scenario, with more variable ranking of the two neonates, which were ranked below patients with considerably worse prognosis. CONCLUSIONS: The value placed on the life of newborns is less than that expected according to predicted clinical outcomes and current legal and ethical theory relative to best interests. Value assessments on the basis of age, disability and prognosis appear to transcend culture, politics and religion in this domain.


Asunto(s)
Toma de Decisiones Clínicas/ética , Toma de Decisiones Clínicas/métodos , Enfermedad Crítica/terapia , Cooperación Internacional , Pautas de la Práctica en Medicina/estadística & datos numéricos , Factores de Edad , Competencia Cultural , Evaluación de la Discapacidad , Humanos , Cuidados para Prolongación de la Vida/métodos , Pronóstico , Encuestas y Cuestionarios
3.
Ultramicroscopy ; 169: 11-21, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27421078

RESUMEN

A novel approach, which is based on the analysis of sequences of images recorded using energy-filtered transmission electron microscopy and can be used to assess the reaction of a solid with a gas at elevated temperature, is illustrated for the reduction of a NiO/ceramic solid oxide fuel cell anode in 1.3mbar of H2. Three-window elemental maps and jump-ratio images of the O K edge and total inelastic mean free path images are recorded as a function of temperature and used to provide local and quantitative information about the reaction kinetics and the volume changes that result from the reaction. Under certain assumptions, the speed of progression of the reaction front in all three dimensions is obtained, thereby providing a three-dimensional understanding of the reaction.

4.
J Diabetes Complications ; 30(8): 1603-1608, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27469295

RESUMEN

BACKGROUND AND AIM: The bone-related peptide osteoprotegerin has been linked to vascular calcification and peripheral vascular disease. We investigated the association between osteoprotegerin and development of foot complications in persons with type 1 diabetes. MATERIALS AND METHODS: Prospective observational study of 573 persons with type 1 diabetes, 225 women; age [mean±SD] 42.3±10.3years. Plasma osteoprotegerin was measured by ELISA. RESULTS: Median (IQR) osteoprotegerin was 2.80(2.35-3.63)µg/L and follow-up time (median (range)) was 12.7(0.1-15.6)years. Endpoints included: new foot ulceration (n=153), Charcot foot (n=14), vascular surgery/amputation (n=53), loss of foot pulse (n=57), and peripheral neuropathy (n=99). In unadjusted analyses, higher osteoprotegerin was associated with development of all endpoints (p≤0.026). Higher osteoprotegerin remained associated with development of foot ulcer, and the combination of vascular surgery/amputation, loss of foot pulse and neuropathy (p≤0.001) in a sex and age adjusted model. After further adjustment (nephropathy status, smoking, HbA1c, systolic blood pressure, serum cholesterol, high sensitivity C-reactive protein, eGFR, and presence of neuropathy and/or claudication and/or foot ulcer at baseline), higher osteoprotegerin remained associated with development of foot ulcer (HR (95% CI) per doubling: 1.75 (1.04-2.97); p=0.037). CONCLUSION: Higher osteoprotegerin levels were associated with development of foot ulcer, even after comprehensive adjustment.


Asunto(s)
Diabetes Mellitus Tipo 1/complicaciones , Pie Diabético/sangre , Osteoprotegerina/sangre , Adulto , Amputación Quirúrgica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
5.
J Hum Hypertens ; 30(1): 46-52, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25810068

RESUMEN

Pulse pressure (PP) remains an elusive cardiovascular risk factor with inconsistent findings. We clarified the prognostic value in patients with type 2 diabetes, chronic kidney disease (CKD) and anemia in the Trial to Reduce cardiovascular Events with Aranesp (darbepoetin alfa) Therapy. In 4038 type 2 diabetes patients, darbepoetin alfa treatment did not affect the primary outcome. Risk related to PP at randomization was evaluated in a multivariable model including age, gender, kidney function, cardiovascular disease (CVD) and other conventional risk factors. End points were myocardial infarction (MI), stroke, end stage renal disease (ESRD) and the composite of cardiovascular death, MI or hospitalization for myocardial ischemia, heart failure or stroke (CVD composite). Median (interquartile range) age, gender, eGFR and PP was 68 (60-75) years, 57.3% women, 33 (27-42) ml min(-1) per 1.73 m2 and 60 (50-74) mm Hg. During 29.1 months (median) follow-up, the number of events for composite CVD, MI, stroke and ESRD was 1010, 253, 154 and 668. In unadjusted analyses, higher quartiles of PP were associated with higher rates per 100 years of follow-up of all end points (P⩽0.04), except stroke (P=0.52). Adjusted hazard ratios (95% confidence interval) per one quartile increase in PP were 1.06 (0.99-1.26) for MI, 0.96 (0.83-1.11) for stroke, 1.01 (0.94-1.09) for ESRD and 1.01 (0.96-1.07) for CVD composite. Results were similar in continuous analyses of PP (per 10 mm Hg). In patients with type 2 diabetes, CKD and anemia, PP did not independently predict cardiovascular events or ESRD. This may reflect confounding by aggressive antihypertensive treatment, or PP may be too rough a risk marker in these high-risk patients.


Asunto(s)
Anemia/tratamiento farmacológico , Anemia/epidemiología , Presión Sanguínea/efectos de los fármacos , Enfermedades Cardiovasculares/epidemiología , Darbepoetina alfa/uso terapéutico , Diabetes Mellitus Tipo 2/epidemiología , Hematínicos/uso terapéutico , Fallo Renal Crónico/epidemiología , Factores de Edad , Anciano , Anemia/complicaciones , Enfermedades Cardiovasculares/complicaciones , Diabetes Mellitus Tipo 2/complicaciones , Femenino , Humanos , Fallo Renal Crónico/complicaciones , Pruebas de Función Renal , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Factores de Riesgo , Factores Sexuales , Resultado del Tratamiento
6.
Diabet Med ; 32(11): 1445-52, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26331364

RESUMEN

AIM: The effect of insulin pump [continuous subcutaneous insulin infusion (CSII)] treatment on diabetes complications in a modern clinical setting is largely unknown. We investigated the effect of 4 years CSII treatment on HbA(1c), albuminuria and kidney function compared with multiple daily injections (MDI) in a single-centre clinical setting. METHODS: All patients initiating CSII treatment from 2004 to 2010 and followed for at least 4 years were included in the study: 193 people with Type 1 diabetes were matched (1 : 2) with 386 patients treated with MDI in the same period. Matching was based on diabetes duration, gender, HbA(1c) and normo-, micro- or macroalbuminuria at baseline. Urinary albumin/creatinine ratio (UACR) was measured yearly and annual change assessed from linear regression. RESULTS: CSII- vs. MDI-treated patients were comparable at baseline. After 4 years, HbA(1c) was 62 ± 11 vs. 68 ± 11 mmol/mol (7.8 ± 1.0 vs. 8.4 ± 1.0%) (P < 0.001). Annual UACR change in CSII- vs. MDI-treated patients was [mean (95% confidence interval)] -10.1 (-13.3; -6.8) vs. -1.2 (-3.6; 0.9)% (P < 0.001). Reduction in UACR was significantly associated with CSII treatment after adjustment for age, gender, diabetes duration, estimated GFR, UACR, mean arterial pressure, HbA(1c), cholesterol, renin-angiotensin-aldosterone system inhibition, anti-hypertensive treatment and smoking (P < 0.001). This remained significant (P < 0.001) when only including patients on stable renin-angiotensin-aldosterone system inhibition during follow-up (n = 465). CONCLUSIONS: Treatment with CSII over 4 years independently reduced HbA(1c) and UACR compared with MDI. Reduced UACR may be due to less glycaemic variability because the effect of CSII on HbA(1c) could only partially explain the effect. This needs confirmation in randomized controlled trials.


Asunto(s)
Diabetes Mellitus Tipo 1/tratamiento farmacológico , Nefropatías Diabéticas/prevención & control , Hiperglucemia/prevención & control , Hipoglucemiantes/administración & dosificación , Sistemas de Infusión de Insulina , Insulina/administración & dosificación , Riñón/efectos de los fármacos , Adulto , Albuminuria/complicaciones , Albuminuria/epidemiología , Albuminuria/prevención & control , Estudios de Cohortes , Dinamarca/epidemiología , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/fisiopatología , Nefropatías Diabéticas/epidemiología , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Hemoglobina Glucada/análisis , Humanos , Hipoglucemiantes/uso terapéutico , Insulina/uso terapéutico , Riñón/fisiopatología , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Insuficiencia Renal/complicaciones , Insuficiencia Renal/epidemiología , Insuficiencia Renal/prevención & control , Riesgo
7.
J Intern Med ; 277(3): 362-371, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24830873

RESUMEN

OBJECTIVES: Soluble urokinase plasminogen activator receptor (suPAR) is a marker of inflammation and endothelial dysfunction. We investigated the associations between suPAR and diabetes, including diabetes duration and complications, in patients with type 1 diabetes. DESIGN, SETTING AND SUBJECTS: From 2009 to 2011, 667 patients with type 1 diabetes and 51 nondiabetic control subjects were included in a cross-sectional study at Steno Diabetes Center, Gentofte, Denmark. suPAR levels were measured with an enzyme-linked immunosorbent assay. MAIN OUTCOME MEASURES: The investigated diabetic complications were cardiovascular disease (CVD: previous myocardial infarction, revascularisation, peripheral arterial disease and stroke), autonomic dysfunction (heart rate variability during deep breathing <11 beats min(-1) ), albuminuria [urinary albumin excretion rate (UAER) ≥30 mg/24 h] or a high degree of arterial stiffness (pulse wave velocity ≥10 m s(-1) ). Analyses were adjusted for gender, age, systolic blood pressure, estimated glomerular filtration rate, UAER, glycated haemoglobin (HbA1c ), total cholesterol, body mass index, C-reactive protein, antihypertensive treatment and smoking. RESULTS: Soluble urokinase plasminogen activator receptor levels were lower in control subjects versus all patients, in control subjects versus normoalbuminuric patients (UAER <30 mg/24 h), in normoalbuminuric patients with short (<10 years) versus long diabetes duration and were increased with degree of albuminuria (adjusted P < 0.001 for all). Furthermore, suPAR levels were higher in patients with versus without CVD (n = 144; 21.3%), autonomic dysfunction (n = 369; 59.2%), albuminuria (n = 357; 53.1%) and a high degree of arterial stiffness (n = 298; 47.2%) (adjusted P ≤ 0.024). The adjusted odds ratio (95% confidence interval) values per 1 ln unit increase in suPAR were as follows: 2.5 (1.1-5.7) for CVD: 2.7 (1.2-6.2) for autonomic dysfunction; 3.8 (1.3-10.9) for albuminuria and 2.5 (1.1-6.1) for a high degree of arterial stiffness (P ≤ 0.039). CONCLUSION: The suPAR level is higher in patients with type 1 diabetes and is associated with diabetes duration and complications independent of other risk factors. suPAR is a potential novel risk marker for the management of diabetes.


Asunto(s)
Complicaciones de la Diabetes/sangre , Diabetes Mellitus Tipo 1/sangre , Receptores del Activador de Plasminógeno Tipo Uroquinasa/metabolismo , Albuminuria/sangre , Albuminuria/etiología , Biomarcadores/metabolismo , Proteína C-Reactiva/metabolismo , Estudios Transversales , Complicaciones de la Diabetes/etiología , Diabetes Mellitus Tipo 1/complicaciones , Angiopatías Diabéticas/sangre , Angiopatías Diabéticas/etiología , Nefropatías Diabéticas/sangre , Nefropatías Diabéticas/etiología , Métodos Epidemiológicos , Femenino , Humanos , Fallo Renal Crónico/sangre , Fallo Renal Crónico/etiología , Masculino , Persona de Mediana Edad
8.
J Hum Hypertens ; 28(9): 535-42, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24430701

RESUMEN

Overweight clusters with high blood pressure (BP), but the independent contribution of both risk factors remains insufficiently documented. In a prospective population study involving 8467 participants (mean age 54.6 years; 47.0% women) randomly recruited from 10 populations, we studied the contribution of body mass index (BMI) to risk over and beyond BP, taking advantage of the superiority of ambulatory over conventional BP. Over 10.6 years (median), 1271 participants (15.0%) died and 1092 (12.9%), 637 (7.5%) and 443 (5.2%) experienced a fatal or nonfatal cardiovascular, cardiac or cerebrovascular event. Adjusted for sex and age, low BMI (<20.7 kg m(-2)) predicted death (hazard ratio (HR) vs average risk, 1.52; P<0.0001) and high BMI (> or = 30.9 kg m(-2)) predicted the cardiovascular end point (HR, 1.27; P=0.006). With adjustments including 24-h systolic BP, these HRs were 1.50 (P<0.001) and 0.98 (P=0.91), respectively. Across quartiles of the BMI distribution, 24-h and nighttime systolic BP predicted every end point (1.13 < or = standardized HR < or = 1.67; 0.046 < or = P<0.0001). The interaction between systolic BP and BMI was nonsignificant (P > or = .22). Excluding smokers removed the contribution of BMI categories to the prediction of mortality. In conclusion, BMI only adds to BP in risk stratification for mortality but not for cardiovascular outcomes. Smoking probably explains the association between increased mortality and low BMI.


Asunto(s)
Monitoreo Ambulatorio de la Presión Arterial , Presión Sanguínea , Índice de Masa Corporal , Hipertensión/diagnóstico , Hipertensión/etnología , Obesidad/diagnóstico , Obesidad/etnología , Adulto , Anciano , Antihipertensivos/uso terapéutico , Asia/epidemiología , Presión Sanguínea/efectos de los fármacos , Europa (Continente)/epidemiología , Femenino , Humanos , Hipertensión/tratamiento farmacológico , Hipertensión/mortalidad , Hipertensión/fisiopatología , Incidencia , Masculino , Persona de Mediana Edad , Obesidad/mortalidad , Obesidad/fisiopatología , Valor Predictivo de las Pruebas , Pronóstico , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo , Fumar/efectos adversos , Fumar/mortalidad , América del Sur/epidemiología , Factores de Tiempo
9.
Nanotechnology ; 24(34): 345301, 2013 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-23899908

RESUMEN

The current understanding in the study of focused electron beam induced processing (FEBIP) is that the growth of a deposit is mainly the result of secondary electrons (SEs). This suggests that the growth rate for FEBIP is affected by the SE emission from the support. Our experiments, with membranes thinner than the SE escape depth, confirm this hypothesis. We used membranes of 1.4 and 4.3 nm amorphous carbon as supports. At the very early stage, the growth is support-dominated and the growth rate on a 4.3 nm thick membrane is three times higher than on a 1.4 nm thick membrane. This is consistent with Monte Carlo simulations for SE emission. The results suggest that SEs are dominant in the dissociation of W(CO)6 on thin membranes. The best agreement between simulations and experiment is obtained for SEs with energies between 3 and 6 eV.With this work we revisit earlier experiments, working at a precursor pressure 20 times lower than previously. Then, despite using membranes thinner than the SE escape depth, we did not see an effect on the experimental growth rate. We explain our current results by the fact that very early in the process, the growth becomes dominated by the growing deposit itself.

10.
Nanotechnology ; 23(48): 485705, 2012 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-23128320

RESUMEN

The mechanical properties of GNP/LDPE nanocomposites (graphite nanoplatelets/low density polyethylene) have been investigated, in order to establish the effect of nanoscale reinforcement within the polymer matrix. Results show that the presence of the filler does not involve a change in the microscopic structure of the polymer. However, on a macroscopic scale, GNPs limit the mobility of the polymer chains, resulting in an increase in stiffness for the final composite. Orientation of GNPs within the LDPE matrix is also an important issue that affects mechanical properties and it has been evaluated by testing nanocomposites made by different manufacturing techniques (compression moulding and blown extrusion). The comparison between the experimental data and the Halpin-Tsai model shows that the orientation of GNPs due to the extrusion process leads to values of tensile modulus higher than that obtained with the randomly oriented disposition resulting from the compression moulding technique.


Asunto(s)
Grafito/química , Nanocompuestos/química , Polietileno/química , Módulo de Elasticidad , Ensayo de Materiales , Nanocompuestos/ultraestructura , Estrés Mecánico
12.
Nanotechnology ; 23(7): 075705, 2012 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-22261463

RESUMEN

Transmission electron microscopy (TEM) makes it possible to obtain insight into the structure, composition and reactivity of photocatalysts, which are of fundamental interest for sustainable energy research. Such insight can be used for further material optimization. Here, we combine conventional TEM analysis of photocatalysts with environmental TEM (ETEM) and photoactivation using light. Two novel types of TEM specimen holder that enable in situ illumination are developed to study light-induced phenomena in photoactive materials, systems and photocatalysts at the nanoscale under working conditions. The technological development of the holders is described and two representative photo-induced phenomena are studied: the photodegradation of Cu2O and the photodeposition of Pt onto a GaN:ZnO photocatalyst.


Asunto(s)
Cobre/química , Microscopía Electrónica de Transmisión/métodos , Fotólisis , Platino (Metal)/química , Catálisis , Galio/química , Luz , Óxido de Zinc/química
13.
Diabet Med ; 29(4): 479-87, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22050462

RESUMEN

AIM: To explore the putative association of new-onset diabetes and the soluble urokinase plasminogen activator receptor (suPAR), which is a new and stable plasma marker of immune function and low-grade inflammation. This association has been previously suggested by using the less sensitive International Classification of Disease system to detect incident diabetes in the Danish MONICA 10 cohort. METHODS: The Danish National Diabetes Register enabled more accurate identification of incident diabetes during a median follow-up of 13.8 years in the Danish MONICA 10 cohort (n = 2353 generally healthy individuals). The soluble urokinase plasminogen activator receptor was measured by the ELISA method. To fulfil model assumptions, outcome analyses were stratified by age, and further by smoking, owing to the interaction between the soluble urokinase plasminogen activator receptor and smoking on new-onset diabetes (P < 0.0001). RESULTS: New-onset diabetes (n = 182) was associated with increased soluble urokinase plasminogen activator receptor levels (P = 0.013). Among 699 middle-aged (41 and 51 years) and 564 older (61 and 71 years) non-smokers, participants in the upper soluble urokinase plasminogen activator receptor quartile had a sex- and age-adjusted relative risk of 6.01 (95% CI 2.17-16.6, P < 0.0006) and relative risk of 3.25 (95% CI 1.51-6.98, P = 0.0025), respectively, for new-onset diabetes compared with participants in the lowest quartile. This relationship remained significant after additional adjustments for C-reactive protein and leukocytes or fasting glucose and insulin or BMI (P < 0.05). The soluble urokinase plasminogen activator receptor was not related to incident diabetes among smokers (P ≥ 0.85). CONCLUSIONS: In these explorative analyses, the soluble urokinase plasminogen activator receptor associated independently with incident diabetes in non-smokers, supporting an immune origin of Type 2 diabetes. Competing disease risk may explain lack of association among smokers.


Asunto(s)
Diabetes Mellitus Tipo 2/sangre , Mediadores de Inflamación/sangre , Receptores del Activador de Plasminógeno Tipo Uroquinasa/sangre , Adulto , Factores de Edad , Anciano , Biomarcadores/sangre , Estudios de Cohortes , Diabetes Mellitus Tipo 2/inmunología , Diabetes Mellitus Tipo 2/fisiopatología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Receptores del Activador de Plasminógeno Tipo Uroquinasa/inmunología , Medición de Riesgo , Factores de Riesgo , Factores Sexuales
14.
Nanotechnology ; 22(50): 505303, 2011 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-22108050

RESUMEN

Focused-electron-beam-induced deposition, or FEBID, enables the fabrication of patterns with sub-10 nm resolution. The initial stages of metal deposition by FEBID are still not fundamentally well understood. For these investigations, graphene, a one-atom-thick sheet of carbon atoms in a hexagonal lattice, is ideal as the substrate for FEBID writing. In this paper, we have used exfoliated few-layer graphene as a support to study the early growth phase of focused-electron-beam-induced deposition and to write patterns with dimensions between 0.6 and 5 nm. The results obtained here are compared to the deposition behavior on amorphous materials. Prior to the deposition experiment, the few-layer graphene was cleaned. Typically, it is observed in electron microscope images that areas of microscopically clean graphene are surrounded by areas with amorphous material. We present a method to remove the amorphous material in order to obtain large areas of microscopically clean graphene flakes. After cleaning, W(CO)(6) was used as the precursor to study the early growth phase of FEBID deposits. It was observed that preferential adsorption of the precursor molecules on step edges and adsorbates plays a key role in the deposition on cleaned few-layer graphene.

15.
Atherosclerosis ; 216(1): 237-43, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21354571

RESUMEN

OBJECTIVE: The soluble urokinase plasminogen activator receptor (suPAR) is a plasma marker of low grade inflammation and has been associated with cardiovascular risk. We wanted to investigate whether suPAR was associated with markers of subclinical organ damage. METHODS: In a population sample of 2038 individuals, aged 41, 51, 61 and 71 years, without diabetes, prior stroke or myocardial infarction, not receiving any cardiovascular, anti-diabetic or lipid-lowering medications, we measured urine albumin/creatinine ratio (UACR), carotid atherosclerotic plaques and carotid/femoral pulse wave-velocity (PWV) together with traditional cardiovascular risk factors and high sensitivity C-reactive protein (hsCRP). RESULTS: suPAR was significantly associated with the presence of plaques (P = 0.003) and UACR (P < 0.001), but not PWV (P = 0.17) when adjusting for age, gender, systolic blood pressure, cholesterol, plasma glucose, waist/hip ratio, smoking and hsCRP. However, suPAR explained only a small part of the variation in the markers of subclinical organ damage (R(2) 0.02-0.04). During a median follow-up of 12.7 years (5th-95th percentile 5.1-13.4 years) a total of 174 composite endpoints (CEP) of cardiovascular death, non-fatal myocardial infarction and stroke occurred. suPAR was associated with CEP independent of plaques, PWV, UACR, and hsCRP as well as age, gender, systolic blood pressure, cholesterol, plasma glucose, waist/hip ratio and smoking with a standardized hazard ratio of 1.16 (95% confidence interval 1.04-1.28, P = 0.006). CONCLUSION: suPAR was associated with subclinical organ damage, but predicted cardiovascular events independent of subclinical organ damage, traditional risk factors and hsCRP. Further studies must investigate whether suPAR plays an independent role in the pathogenesis of cardiovascular disease.


Asunto(s)
Albuminuria/complicaciones , Aterosclerosis/complicaciones , Enfermedades Cardiovasculares/etiología , Inflamación/complicaciones , Placa Aterosclerótica/complicaciones , Receptores del Activador de Plasminógeno Tipo Uroquinasa/sangre , Adulto , Anciano , Albuminuria/sangre , Albuminuria/mortalidad , Albuminuria/fisiopatología , Análisis de Varianza , Enfermedades Asintomáticas , Aterosclerosis/sangre , Aterosclerosis/diagnóstico por imagen , Aterosclerosis/mortalidad , Aterosclerosis/fisiopatología , Biomarcadores/sangre , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/mortalidad , Enfermedades Cardiovasculares/fisiopatología , Arteria Carótida Común/fisiopatología , Distribución de Chi-Cuadrado , Adaptabilidad , Dinamarca/epidemiología , Femenino , Arteria Femoral/fisiopatología , Humanos , Inflamación/sangre , Inflamación/mortalidad , Inflamación/fisiopatología , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Placa Aterosclerótica/sangre , Placa Aterosclerótica/diagnóstico por imagen , Placa Aterosclerótica/mortalidad , Placa Aterosclerótica/fisiopatología , Modelos de Riesgos Proporcionales , Flujo Pulsátil , Medición de Riesgo , Factores de Riesgo , Ultrasonografía
16.
Nanotechnology ; 22(11): 115303, 2011 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-21301081

RESUMEN

It is often suggested that the growth in focused electron beam induced processing (FEBIP) is caused not only by primary electrons, but also (and even predominantly) by secondary electrons (SEs). If that is true, the growth rate for FEBIP can be changed by modifying the SE yield. Results from our Monte Carlo simulations show that the SE yield changes strongly with substrate thickness for thicknesses below the SE escape depth. However, our experimental results show that the growth rate is independent of the substrate thickness. Deposits with an average size of about 3 nm were written on 1 and 9 nm thick carbon substrates. The apparent contradiction between simulation and experiment is explained by simulating the SE emission from a carbon substrate with platinum deposits on the surface. It appears that the SE emission is dominated by the deposits rather than the carbon substrate, even for deposits as small as 0.32 nm(3).

17.
Acta Paediatr ; 100(4): 499-505, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21114525

RESUMEN

UNLABELLED: Jaundice is the most common reason for instituting treatment in otherwise healthy as well as sick newborn infants. Herein, we describe the process employed in Norway to forge agreement on a set of treatment guidelines that are now used across the country. The Norwegian Pediatric Association was a key resource in this process, which involved contacts with all paediatric departments in Norway. We have also performed an international survey regarding the use of such national guidelines, showing that the majority of those queried confirm having national guidelines. The evidence base for any neonatal jaundice guideline is weak; therefore, it is not surprising that the various guidelines differ both in format and in specifics. In the Norwegian guidelines, treatment indications are based on bilirubin concentrations and related to birth weight. Postnatal age is also factored in because jaundice develops gradually during the first 3-4 days before it levels off. CONCLUSION: Following the introduction of these guidelines, fewer babies in Norway receive phototherapy, and no cases of chronic kernicterus have been reported during this period.


Asunto(s)
Enfermedades del Prematuro/terapia , Ictericia Neonatal/terapia , Guías de Práctica Clínica como Asunto , Medicina Basada en la Evidencia , Humanos , Recién Nacido , Enfermedades del Prematuro/sangre , Internacionalidad , Ictericia Neonatal/sangre , Noruega , Fototerapia
18.
J Intern Med ; 268(3): 296-308, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20561148

RESUMEN

BACKGROUND: Low-grade inflammation is thought to contribute to the development of cardiovascular disease (CVD), type-2 diabetes mellitus (T2D), cancer and mortality. Biomarkers of inflammation may aid in risk prediction and enable early intervention and prevention of disease. OBJECTIVE: The aim of this study was to investigate whether plasma levels of the inflammatory biomarker soluble urokinase plasminogen activator receptor (suPAR) are predictive of disease and mortality in the general population. DESIGN: This was an observational prospective cohort study. Cohort participants were included from June 1993 to December 1994 and followed until the end of 2006. SETTING: General adult Caucasian population. PARTICIPANTS: The MONICA10 study, a population-based cohort recruited from Copenhagen, Denmark, included 2602 individuals aged 41, 51, 61 or 71 years. MEASUREMENTS: Blood samples were analysed for suPAR levels using a commercially available enzyme-linked immunosorbent assay. Risk of cancer (n = 308), CVD (n = 301), T2D (n = 59) and mortality (n = 411) was assessed with a multivariate proportional hazards model using Cox regression. RESULTS: Elevated baseline suPAR level was associated with an increased risk of cancer, CVD, T2D and mortality during follow-up. suPAR was more strongly associated with cancer, CVD and mortality in men than in women, and in younger compared with older individuals. suPAR remained significantly associated with the risk of negative outcome after adjustment for a number of relevant risk factors including C-reactive protein levels. LIMITATION: Further validation in ethnic populations other than Caucasians is needed. CONCLUSION: The stable plasma protein suPAR may be a promising biomarker because of its independent association with incident cancer, CVD, T2D and mortality in the general population.


Asunto(s)
Enfermedades Cardiovasculares/diagnóstico , Diabetes Mellitus Tipo 2/diagnóstico , Neoplasias/diagnóstico , Receptores del Activador de Plasminógeno Tipo Uroquinasa/sangre , Adulto , Distribución por Edad , Anciano , Biomarcadores/sangre , Biomarcadores de Tumor/sangre , Proteína C-Reactiva/metabolismo , Enfermedades Cardiovasculares/epidemiología , Dinamarca/epidemiología , Diabetes Mellitus Tipo 2/epidemiología , Métodos Epidemiológicos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/epidemiología , Pronóstico , Distribución por Sexo
19.
J Hum Hypertens ; 23(2): 105-12, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18784734

RESUMEN

The study aim was to determine whether urine albumin/creatinine ratio (UACR), high-sensitivity C-reactive protein (hsCRP) or N-terminal pro-brain natriuretic peptide (Nt-proBNP) added to risk prediction based on HeartScore and history of diabetes or cardiovascular disease. A Danish population sample of 2460 individuals was divided in three groups: 472 subjects receiving cardiovascular medication or having history of diabetes, prior myocardial infarction or stroke, 559 high-risk subjects with a 10-year risk of cardiovascular death above 5% as estimated by HeartScore, and 1429 low-moderate risk subjects with estimated risk below 5%. During the following 9.5 years the composite end point of cardiovascular death, non-fatal myocardial infarction or stroke (CEP) occurred in 204 subjects. CEP was predicted in all three groups by UACR (HRs: 2.1, 2.1 and 2.3 per 10-fold increase, all P<0.001) or by hsCRP (HRs: 1.9, 1.9 and 1.7 per 10-fold increase, all P<0.05), but not by Nt-proBNP (HRs: 1.1, 2.6 and 3.7 per 10-fold increase, last two P<0.001) (P<0.05 for interaction). In the low-moderate risk group, pre-specified gender adjusted (men/women) cutoff values of UACR> or =0.73/1.06 mg mmol(-1) or hsCRP> or =6.0/7.3 mg l(-1) identified a subgroup of 16% who experienced one-third of the CEPs. In the patient group, combined absence of high UACR and high Nt-proBNP> or =110/164 pg ml(-1) (men/women) identified a subgroup of 52% who experienced only 15% of the CEPs. Additional use of UACR and hsCRP in subjects with low-moderate risk and UACR and Nt-proBNP in subjects with known diabetes of cardiovascular disease changed HeartScore risk classification significantly in 19% of the population.


Asunto(s)
Albuminuria/metabolismo , Proteína C-Reactiva/metabolismo , Enfermedades Cardiovasculares/etiología , Creatina/metabolismo , Indicadores de Salud , Péptido Natriurético Encefálico/metabolismo , Fragmentos de Péptidos/metabolismo , Adulto , Biomarcadores/metabolismo , Enfermedades Cardiovasculares/metabolismo , Enfermedades Cardiovasculares/mortalidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Medición de Riesgo
20.
J Hum Hypertens ; 22(9): 634-40, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18528412

RESUMEN

Although the metabolic syndrome (MetS) is positively associated with high-sensitivity C-reactive protein (hsCRP), negatively associated with N-terminal pro-brain natriuretic peptide (Nt-proBNP) and inconsequently related to urine albumin/creatinine ratio (UACR) they are all associated with cardiovascular events. Therefore, we wanted to determine the influence of MetS on the predictive values of UACR, hsCRP and Nt-proBNP. On the basis of the definition of MetS by the International Diabetes Federation, a Danish population sample of 1983 apparently healthy subjects was divided into three groups: 530 subjects without any elements of MetS, 1093 subjects with some elements of MetS and 360 subjects with MetS. During the following 9.5 years the composite end point of cardiovascular death, non-fatal myocardial infarction or stroke (composite cardiovascular end point, CEP) occurred in 204 subjects. In Cox-regression analyses adjusting for age, gender and smoking, all three cardiovascular risk markers predicted CEP independently of MetS. Despite no significant interaction with MetS, high log(hsCRP) was associated with CEP primarily in subjects without any elements of MetS (hazard ratio (HR)=4.5 (1.5-14.0), P<0.01), log(Nt-proBNP) primarily in subjects with some elements of MetS (HR=3.0 (1.6-5.6), P<0.01), and logUACR independently of elements of MetS. Pre-specified gender-adjusted (men/women) cutoff values of hsCRP > or = 6.0/7.3 mg l(-1) predicted CEP in subjects without elements of MetS with positive and predictive values of 11.5 and 98%, respectively. UACR > or = 0.73/1.06 mg mmol(-1) predicted CEP in subjects with MetS with positive and predictive values of 23.5 and 93%, respectively. In apparently healthy subjects, high hsCRP was associated with CEP primarily in subjects without MetS, high Nt-proBNP in subjects with elements of MetS and UACR independently of MetS.


Asunto(s)
Albuminuria/orina , Biomarcadores/análisis , Proteína C-Reactiva/análisis , Creatinina/orina , Síndrome Metabólico/metabolismo , Péptido Natriurético Encefálico/sangre , Fragmentos de Péptidos/sangre , Adulto , Anciano , Enfermedades Cardiovasculares/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Análisis de Regresión , Factores de Riesgo
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