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Metastable states created by electron or hole capture in crystal defects are widely used in dosimetry and photonic applications. Feldspar, the most abundant mineral in the Earth's crust (> 50%), generates metastable states with lifetimes of millions of years upon exposure to ionizing radiation. Although feldspar is widely used in dosimetry and geochronometry, the creation of metastable states and charge transfer across them is poorly understood. Understanding such phenomena requires next-generation methods based on high-resolution, site-selective probing of the metastable states. Recent studies using site-selective techniques such as photoluminescence (PL), and radioluminescence (RL) at 7 K have revealed that feldspar exhibits two near-infrared (NIR) emission bands peaking at 880 nm and 955 nm, which are believed to arise from the principal electron-trapping states. Here, we map for the first time the electron-trapping states in potassium-rich feldspar using spectrally-resolved cathodoluminescence microscopy at a spatial resolution of ~ 6 to 22 µm. Each pixel probed by a scanning electron microscope provides us a cathodoluminescence spectrum (SEM-CL) in the range 600-1000 nm, and elemental data from energy-dispersive x-ray (EDX) spectroscopy. We conclude that the two NIR emissions are spatially variable and, therefore, originate from different sites. This conclusion contradicts the existing model that the two emissions arise from two different excited states of a principal trap. Moreover, we are able to link the individual NIR emission peaks with the geochemical variations (K, Na and Fe concentration), and propose a model that explains the quenching of the NIR emission by Fe4+. Our study contributes to an improved understanding of charge storage in feldspathic minerals, with implications for developing sub-single grain (micrometer scale) measurement techniques in radiation dosimetry.
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OBJECTIVES: Cardiopulmonary exercise test (CPET) provides accurate evaluation of physical capacity and disease severity in children with congenital heart disease (CHD). However, full participation to obtain optimal measure of VO2max may be difficult. As an alternative, the oxygen uptake efficiency slope (OUES) is a reproducible and reliable parameter measured during CPET, which does not require a maximal exercise to be interpretable. This study aimed to evaluate the OUES of a large cohort of children with CHD, in comparison with healthy controls. We also intended to identify, in this specific population, the clinical and CPET variables associated with the OUES. METHODS: This cross-sectional study was carried out between November 2010 and September 2015 in two tertiary care paediatric and congenital cardiology centres. RESULTS: 709 children were included (407 CHD and 302 healthy controls). The association of clinical characteristics with weight-normalised OUES (OUESkg) was studied using a multivariable analysis. The mean OUESkg was significantly lower in CHD than in healthy controls (38.6±8.5 and 43.9±8.5; p<0.001, respectively), especially in the most severe CHD. The OUESkg correlated with VO2max (r=0.85, p<0.001), with cut-off values for normal exercise capacity of 38.4 in boys and 31.0 in girls. The decrease of OUESkg was associated with increased age, increased Body Mass Index, number of cardiac catheter or surgical procedures, female gender and decreased forced vital capacity (Z-score). CONCLUSION: The OUES is significantly impaired in children with CHD and strongly correlates with VO2max. The OUES has the same clinical determinants as VO2max and therefore may be of interest in submaximal exercise. TRIAL REGISTRATION NUMBER: NCT01202916.
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Tolerancia al Ejercicio/fisiología , Cardiopatías Congénitas/fisiopatología , Consumo de Oxígeno , Adolescente , Factores de Edad , Índice de Masa Corporal , Cateterismo Cardíaco , Procedimientos Quirúrgicos Cardíacos , Estudios de Casos y Controles , Niño , Estudios Transversales , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Factores Sexuales , Capacidad VitalRESUMEN
BACKGROUND: Advances in congenital heart disease (CHD) have transferred the mortality from childhood to adulthood. Exercise capacity in young patients with CHD remains lower than in the general population, resulting in deconditioning and impaired quality of life. Evidence based-medicine in cardiac rehabilitation in this age group with CHD remains limited. We present the QUALI-REHAB study rationale, design and methods. METHODS: The QUALI-REHAB trial is a nationwide, multicentre, randomised, controlled study, aiming to assess the impact of a combined centre and home-based cardiac rehabilitation program on the quality of life of adolescents and young adults (13 to 25â¯years old) with CHD. Patients with a maximum oxygen uptake (VO2max)â¯<â¯80% and/or a ventilatory anaerobic threshold (VAT)â¯<â¯55% of predicted VO2max, will be eligible. Patients will be randomised into 2 groups (12-week cardiac rehabilitation program vs. controls). The primary outcome is the change in the PedsQL quality of life score between baseline and 12-month follow-up. A total of 130 patients are required to observe a significant increase of 7⯱â¯13.5 points in the PedsQL, with a power of 80% and an alpha risk of 5%. The secondary outcomes are: VO2max, VAT, stroke volume, clinical outcomes, physical and psychological status, safety and acceptability. CONCLUSION: After focusing on the survival in CHD, current research is opening on secondary prevention and patient-related outcomes. The QUALI-REHAB trial intends to assess if a combined centre and home-based rehabilitation program, could improve the quality of life and the exercise capacity in youth with CHD. TRIAL REGISTRATION: Clinicaltrials.gov (NCT03690518).
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Rehabilitación Cardiaca/métodos , Tolerancia al Ejercicio/fisiología , Cardiopatías Congénitas/rehabilitación , Servicios de Atención de Salud a Domicilio , Calidad de Vida , Adolescente , Adulto , Femenino , Estudios de Seguimiento , Cardiopatías Congénitas/fisiopatología , Cardiopatías Congénitas/psicología , Humanos , Masculino , Estudios Prospectivos , Resultado del Tratamiento , Adulto JovenRESUMEN
BACKGROUND: The use of hypnosis in children has been described more than two centuries ago, with a more recent research and clinical application. There is currently a good level of evidence for the efficacy of clinical hypnosis in children for minor surgery, medical procedures or pain management. The use of clinical hypnosis, in paediatric cardiology, for invasive procedures such as transesophageal echocardiography, has not been reported. AIMS: This study evaluated the feasibility of clinical hypnosis in children undergoing transesophageal echocardiography. METHOD: This prospective, non-randomised, cross-sectional study was carried out over 24 months in a paediatric cardiology referral centre. All children aged 10-18 years requiring a transesophageal echocardiography examination, outside the operating room and the catheterisation laboratory, were eligible for the study. Children and families could choose between transesophageal echocardiography under clinical hypnosis or under general anaesthesia (<15 years) or sedation (⩾15 years). RESULTS: We included 16 children aged 11-18 years (seven girls, mean age 14.1±2.5 years). The hypnotic state was achieved for 15 out of the 16 participating children (94%). The transesophageal echocardiography examination could be completely achieved with a full diagnosis for 15 out of 16 children (94%). In all cases, a transesophageal echocardiography examination under clinical hypnosis provided a complete diagnosis. CONCLUSION: This study demonstrated that hypnosis was feasible and effective for transesophageal echocardiography in adolescents and might be a good alternative to general anaesthesia. Further study with larger numbers of subjects and more diverse congenital cardiac conditions are needed to confirm the results in a more diverse sample.
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Ecocardiografía Transesofágica/normas , Cardiopatías Congénitas/diagnóstico , Hipnosis/métodos , Pediatría/normas , Guías de Práctica Clínica como Asunto , Adolescente , Niño , Estudios Transversales , Estudios de Factibilidad , Femenino , Humanos , Masculino , Estudios ProspectivosRESUMEN
BACKGROUND: Myocardial salvage is an important surrogate endpoint to estimate the impact of treatments in patients with ST-segment elevation myocardial infarction (STEMI). AIM: The aim of this study was to evaluate the correlation between cardiac sympathetic denervation area assessed by single-photon emission computed tomography (SPECT) using iodine-123-meta-iodobenzylguanidine (I-MIBG) and myocardial area at risk (AAR) assessed by cardiac magnetic resonance (CMR) (gold standard). PATIENTS AND METHODS: A total of 35 postprimary reperfusion STEMI patients were enrolled prospectively to undergo SPECT using I-MIBG (evaluates cardiac sympathetic denervation) and thallium-201 (evaluates myocardial necrosis), and to undergo CMR imaging using T2-weighted spin-echo turbo inversion recovery for AAR and postgadolinium T1-weighted phase sensitive inversion recovery for scar assessment. RESULTS: I-MIBG imaging showed a wider denervated area (51.1±16.0% of left ventricular area) in comparison with the necrosis area on thallium-201 imaging (16.1±14.4% of left ventricular area, P<0.0001). CMR and SPECT provided similar evaluation of the transmural necrosis (P=0.10) with a good correlation (R=0.86, P<0.0001). AAR on CMR was not different compared with the denervated area (P=0.23) and was adequately correlated (R=0.56, P=0.0002). Myocardial salvage evaluated by SPECT imaging (mismatch denervated but viable myocardium) was significantly higher than by CMR (P=0.02). CONCLUSION: In patients with STEMI, I-MIBG SPECT, assessing cardiac sympathetic denervation may precisely evaluate the AAR, providing an alternative to CMR for AAR assessment.
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3-Yodobencilguanidina , Infarto del Miocardio/diagnóstico por imagen , Tomografía Computarizada de Emisión de Fotón Único , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Medición de RiesgoAsunto(s)
Cardiopatías/diagnóstico por imagen , Cardiopatías/tratamiento farmacológico , Embolia Pulmonar/diagnóstico por imagen , Embolia Pulmonar/tratamiento farmacológico , Terapia Trombolítica/métodos , Anciano de 80 o más Años , Fibrinolíticos/uso terapéutico , Cardiopatías/complicaciones , Humanos , Masculino , Embolia Pulmonar/complicacionesRESUMEN
PURPOSE: A suggestion for a graduated diagnostic and therapeutic approach for patients with a suspected infection with non-tuberculous mycobacteria (NTM) of the hand and wrist is made. PATIENTS AND METHODS: Between March 2003 and February 2007, 2 women and 3 men with an average age of 64 years were treated for an NTM infection of the hand and wrist. 4 patients had a tenosynovitis of the wrist. In 1 patient both wrists were involved. 1 patient had a granuloma of the index finger. The patients' charts, the operation reports, histological and bacteriological findings and the antibiogram were evaluated. RESULTS: An inoculating trauma was identified in four patients. Intraoperatively rice bodies were present in the 4 patients with a tenosynovitis of the wrist. Histological findings showed acid-fast bacilli in 2 patients and chronic inflammatory reaction with/without granuloma (3/2) in 5 patients. Species identification was based on PCR and microbiological culture and revealed in three patients slow growing species (M. malmoense, M. nonchromogenicum, M. szulgai) and in two patients M. marinum (intermediate growth rate). Therapy consisted of immediate postoperative empirical combined drug treatment followed by antibiogram-based therapy. All patients showed healing of the infection at the final follow-up at an average of 25.2 months (range: 15-44 months) postoperatively. CONCLUSION: Consideration of non-tuberculous mycobacteria in the differential diagnosis in cases of localised tenosynovitis is paramount for diagnosis. Treatment based on graduated diagnostic steps, surgery and drugs (empirical followed by directed drugs) can achieve favourable clinical outcomes.
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Traumatismos de la Mano/cirugía , Infecciones por Mycobacterium no Tuberculosas/cirugía , Tenosinovitis/cirugía , Infección de Heridas/cirugía , Traumatismos de la Muñeca/cirugía , Anciano , Antibacterianos/uso terapéutico , Comorbilidad , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Traumatismos de la Mano/diagnóstico , Humanos , Enfermedad Iatrogénica , Masculino , Persona de Mediana Edad , Infecciones por Mycobacterium no Tuberculosas/diagnóstico , Mycobacterium marinum , Micobacterias no Tuberculosas , Infecciones Oportunistas/diagnóstico , Infecciones Oportunistas/cirugía , Tenosinovitis/diagnóstico , Infección de Heridas/diagnóstico , Traumatismos de la Muñeca/diagnósticoRESUMEN
The reliability of equivalent doses (De) from Chinese loess, measured using isothermal thermoluminescence (ITL) is tested. Dose calculations use the single-aliquot regenerative-dose (SAR) procedure. Despite good reproducibility of laboratory-induced signals and negligible response at zero dose, a significant overestimation of De is observed, compared with OSL measurements. Measurement of a known laboratory dose administered after optical bleaching, but before any heating, demonstrates that the first heating during measurement of the natural signal causes a significant sensitivity change, undetected by SAR. Using the single-aliquot regeneration and added (SARA) dose procedure, which allows for initial sensitivity change, good agreement with OSL is obtained after allowance is made for initial incomplete bleaching. It is concluded that SAR-ITL, in its present form, is not a suitable method for dating Chinese loess; it is very important to undertake a dose recovery test before any TL procedure is used to date sediments.
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Sedimentos Geológicos/química , Calor , Ensayo de Materiales/métodos , Cuarzo/química , Cuarzo/efectos de la radiación , Dosimetría Termoluminiscente/métodos , China , Semivida , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
In the age determination of sediments according to the luminescence method, it is important to know whether there was secular equilibrium in the Th and U decay series during accumulation of the environmental radiation dose in geological times. This can be investigated via gamma-ray spectrometry, whereby--in the (238)U series--(214)Pb and (214)Bi are considered as the indicators for (226)Ra-mobility, and (210)Pb as the indicator for (226)Rn-emanation. In the present work, the direct measurement of (226)Ra--which can give extra information on the interpretation of the radioactive equilibrium--is investigated as to its precision and accuracy. Since there is a serious spectral interference on its 186.2keV gamma-line (by (235)U at 185.7keV), various correction procedures were outlined and their performance was checked via the analysis of (certified) reference materials, leading to the recommendation of a "method of choice".
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Conservative treatment of fractures of the scaphoid often leads to an important physical and economic morbidity, especially in the young and active population. Acute percutaneous scaphoid fixation is a fast technique with minimal soft tissue damage, which allows immediate mobilisation without prolonged casting. We describe our operation technique in which we always use a non-cannulated Herbert screw. We place the screw freehand and always pass through the trapezium, a technique which is in our hands the best way to place the screw in the right position. It is not technically demanding, but has a considerable learning curve and requires a three-dimensional knowledge of the scaphoid. We reviewed the results of 44 patients treated in our centre between 1996 and 2001. Comparing with literature of percutaneous scaphoid fixation, we found similar results. Although in literature this technique is only indicated for minimally and non-displaced fractures of the waist (Herbert A2 and B2), we describe some good results with proximal pole fractures. Nevertheless we found that all cases of delayed and non-union occurred with this type of fracture.
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Fijación Interna de Fracturas/instrumentación , Fracturas Óseas/cirugía , Procedimientos Quirúrgicos Mínimamente Invasivos/instrumentación , Hueso Escafoides/cirugía , Absentismo , Enfermedad Aguda , Adolescente , Adulto , Anciano , Fenómenos Biomecánicos , Tornillos Óseos/normas , Femenino , Fluoroscopía , Estudios de Seguimiento , Fijación Interna de Fracturas/efectos adversos , Fijación Interna de Fracturas/métodos , Curación de Fractura , Fracturas Óseas/clasificación , Fracturas Óseas/diagnóstico por imagen , Fracturas Óseas/fisiopatología , Fracturas no Consolidadas/etiología , Fuerza de la Mano , Humanos , Masculino , Persona de Mediana Edad , Procedimientos Quirúrgicos Mínimamente Invasivos/efectos adversos , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Ocupaciones , Radiografía Intervencional , Rango del Movimiento Articular , Supinación , Resultado del TratamientoRESUMEN
A transformation system was developed for Artemisia annua L. plants. Leaf explants from in vitro grown plants developed callus and shoots on medium with 0.05 mg/L naphthaleneacetic acid and 0.5 mg/L N(6)-benzyladenine after transformation with the C58C1 Rif(R) (pGV2260) (pTJK136) Agrobacterium tumefaciens strain. A concentration of 20 mg/L kanamycin was added in order to select transformed tissue. Kanamycin resistant shoots were rooted on naphthaleneacetic acid 0.1 mg/L. Polymerase chain reactions and DNA sequencing of the amplification products revealed that 75% of the regenerants contained the foreign genes. 94% of the transgenic plants showed a ß-glucuronidase-positive response.
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A factor present in conditioned medium of COLO-16 human cancer cells causes fast spreading, fast plasma membrane ruffling, cell shape change, net translocation, stimulation of chemotaxis and growth arrest in human SK-BR-3 mammary cancer cells. Based on the spreading effect, the factor was purified to homogeneity and migrated as a 50 kDa protein in SDS-polyacrylamide gel electrophoresis. Addition of the purified 50 kDa factor to the target cells in culture results in tyrosine phosphorylation of the p185erbB2 receptor concomitant with a fast redistribution and clustering of the receptor. The 50 kDa factor is also specifically retained by affinity chromatography on the immobilized extracellular domain of p185erbB2. Antibodies directed against this domain also inhibit the induction of motility. These data suggest that the 50 kDa factor is a putative ligand of p185erbB2 in SK-BR-3 cells. Biochemical and immunological evidence further indicate that this factor differs from p185erbB2 ligands described so far. Its activity could play a role in the pathogenesis of breast cancer.
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Receptores ErbB/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Tirosina/metabolismo , Animales , Anticuerpos/inmunología , Secuencia de Bases , División Celular , Línea Celular , Movimiento Celular , Medios de Cultivo Condicionados , ADN , Receptores ErbB/biosíntesis , Receptores ErbB/inmunología , Humanos , Ligandos , Neoplasias Mamarias Animales/metabolismo , Datos de Secuencia Molecular , Fosforilación , Proteínas Proto-Oncogénicas/biosíntesis , Proteínas Proto-Oncogénicas/inmunología , Receptor ErbB-2 , Células Tumorales CultivadasRESUMEN
Between January 1970 and December 1985, 76 patients (76 fractures) underwent internal fixation for tibial-plateau fractures as recommended by the AO-group (14). Fifty patients were available for follow-up. The long term results of this retrospective study are reported. Subjective results were satisfying. Forty-four percent of the patients were painfree and only 8% had severe postoperative pain, which was clearly related to osteoarthritis. Eight-eight percent of patients had no instability at follow-up. Clinical and radiographic results were evaluated for mobility, laxity and osteoarthritis. Thirty-five patients had a loss of flexion averaging 16.6 degrees. In 12 patients the average decrease in extension amounted to 7.5 degrees. Valgus increase averaged 9.7 degrees in 17 patients, and the average varus increase was 7.5 degrees in 4 patients. Seventy-four percent of patients showed no laxity at follow-up. The finding of osteoarthritis on X-ray was well correlated with the postoperative incongruence of the articular surface. It was also found to develop earlier in patients who underwent (partial) meniscectomy. Some general considerations about tibial condyles fractures are presented, and the technique used by the authors is discussed at length. The indications for internal fixation are also evaluated. The importance of adequate reduction, stable internal fixation and vigorous postoperative rehabilitation is stressed.