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1.
Phys Rev Lett ; 131(16): 166901, 2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37925701

RESUMEN

Two-photon resonant excitation of the biexciton-exciton cascade in a quantum dot generates highly polarization-entangled photon pairs in a near-deterministic way. However, the ultimate level of achievable entanglement is still debated. Here, we observe the impact of the laser-induced ac-Stark effect on the quantum dot emission spectra and on entanglement. For increasing pulse-duration-to-lifetime ratios and pump powers, decreasing values of concurrence are recorded. Nonetheless, additional contributions are still required to fully account for the observed below-unity concurrence.

2.
Hamostaseologie ; 33 Suppl 1: S39-45, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24170271

RESUMEN

The development of inhibitory anti-FVIII antibodies is currently the most severe complication in the treatment of haemophilia A patients. Inhibitor eradication can be achieved by immune tolerance induction (ITI). Recent findings suggest a correlation between the FVIII-specific IgG subclass distribution and the duration or outcome of ITI. To quantify FVIII-specific IgG subclasses in patients' plasma FVIII-specific IgG standards are required. Here, the isolation of FVIII-specific single chain variable fragments (scFvs) from synthetic phage display libraries and the characterisation of their FVIII domain specificity are described. The isolated scFv 1G10, which binds to the FVIII A2 domain, was cloned into the context of the four human IgG (hIgG) subclasses and expressed in mammalian cells. Purified 1G10-hIgG1, -hIgG2, -hIgG3 and -hIgG4 are used as standards to determine the absolute amounts and relative contribution of the different FVIII-specific IgG subclasses in future studies. The results from these studies will eventually add to understanding the role of the FVIII-specific IgG subclass distribution as prognostic factor for the outcome of ITI.


Asunto(s)
Coagulación Sanguínea/efectos de los fármacos , Diseño de Fármacos , Factor VIII/química , Factor VIII/farmacología , Anticuerpos de Cadena Única/química , Anticuerpos de Cadena Única/farmacología , Factor VIII/genética , Estructura Terciaria de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacología , Anticuerpos de Cadena Única/genética , Relación Estructura-Actividad
3.
J Appl Physiol (1985) ; 109(4): 1064-71, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20705944

RESUMEN

The aim was to describe diaphragmatic behavior during postural limb activities and examine the ventilatory and stabilizing functions of the diaphragm. Thirty healthy subjects were examined in the supine position using a dynamic MRI system assessed simultaneously with specialized spirometric readings. The diaphragmatic excursions (DEs) were measured at three diaphragmatic points in the sagittal plane; the diaphragm positions (DPs) as related to a reference horizontal baseline were determined. Measurements were taken during tidal breathing (TB) and isometric flexion of upper or lower extremities against external resistance together with TB. Mean DE in both upper and lower postural limb activities was greater compared with the TB condition (P < 0.05), with the effect greater for lower limb activities. Inspiratory DPs in the upper and lower extremity activities were lower compared with TB alone (P < 0.01). Expiratory DP was lower only for lower extremity activities (P < 0.01). DP was most affected at the apex of the crescent and crural (posterior) portion of the diaphragm. DEs correlated strongly with tidal volume (Vt) in all conditions. Changes in DEs relative to the initial value were minimal for upper and lower extremities but were related to lower values of Vt (P < 0.03). Significant involvement of the diaphragm in the limb postural activities was found. Resulting DEs and DPs differed from the TB conditions, especially in lower extremity activities. The differences between the percent changes of DEs vs. Vt found for lower extremity activities were confirmed by both ventilatory and postural diaphragm recruitment in response to postural demands.


Asunto(s)
Diafragma/anatomía & histología , Diafragma/fisiología , Contracción Isométrica , Imagen por Resonancia Magnética , Equilibrio Postural , Ventilación Pulmonar , Mecánica Respiratoria , Espirometría , Adulto , Femenino , Volumen Espiratorio Forzado , Humanos , Extremidad Inferior , Masculino , Persona de Mediana Edad , Valores de Referencia , Entrenamiento de Fuerza , Posición Supina , Volumen de Ventilación Pulmonar , Factores de Tiempo , Extremidad Superior , Capacidad Vital , Adulto Joven
4.
Physiol Res ; 58(3): 383-392, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-18637703

RESUMEN

Using magnetic resonance imaging (MRI) in conjunction with synchronized spirometry we analyzed and compared diaphragm movement during tidal breathing and voluntary movement of the diaphragm while breath holding. Breathing cycles of 16 healthy subjects were examined using a dynamic sequence (77 slices in sagittal plane during 20 s, 1NSA, 240x256, TR4.48, TE2.24, FA90, TSE1, FOV 328). The amplitude of movement of the apex and dorsal costophrenic angle of the diaphragm were measured for two test conditions: tidal breathing and voluntary breath holding. The maximal inferior and superior positions of the diaphragm were subtracted from the corresponding positions during voluntary movements while breath holding. The average amplitude of inferio-superior movement of the diaphragm apex during tidal breathing was 27.3+/-10.2 mm (mean +/- SD), and during voluntary movement while breath holding was 32.5+/-16.2 mm. Movement of the costophrenic angle was 39+/-17.6 mm during tidal breathing and 45.5+/-21.2 mm during voluntary movement while breath holding. The inferior position of the diaphragm was lower in 11 of 16 subjects (68.75 %) and identical in 2 of 16 (12.5 %) subjects during voluntary movement compared to the breath holding. Pearson's correlation coefficient was used to demonstrate that movement of the costophrenic angle and apex of the diaphragm had a linear relationship in both examined situations (r=0.876). A correlation was found between the amplitude of diaphragm movement during tidal breathing and lung volume (r=0.876). The amplitude of movement of the diaphragm with or without breathing showed no correlation to each other (r=0.074). The movement during tidal breathing shows a correlation with the changes in lung volumes. Dynamic MRI demonstrated that individuals are capable of moving their diaphragm voluntarily, but the amplitude of movement differs from person to person. In this study, the movements of the diaphragm apex and the costophrenic angle were synchronous during voluntary movement of the diaphragm while breath holding. Although the sample is small, this study confirms that the function of the diaphragm is not only respiratory but also postural and can be voluntarily controlled.


Asunto(s)
Diafragma/fisiología , Imagen por Resonancia Magnética , Contracción Muscular , Relajación Muscular , Respiración , Adulto , Electromiografía , Femenino , Humanos , Mediciones del Volumen Pulmonar , Masculino , Persona de Mediana Edad , Presión , Valores de Referencia , Mecánica Respiratoria , Espirometría , Volición , Adulto Joven
5.
Acta Chir Orthop Traumatol Cech ; 74(1): 29-36, 2007 Feb.
Artículo en Checo | MEDLINE | ID: mdl-17331452

RESUMEN

PURPOSE OF THE STUDY: The authors present the results of surgical treatment of talar dome cartilage defects. They used the transplantation of autologous cultured chondrocytes in the form of a solid chondral graft. MATERIAL AND METHODS: Patients with chondral lesions categorized as grades II to IV by the Anderson classification or as grades II to IV by the Berndt and Harty classification were indicated for this treatment. After preoperative MRI examination, a small sample of healthy cartilage was harvested arthroscopically from the non-weight-bearing area of the talus and was sent to the Tissue Bank in Brno for chondrocyte cultivation. After 28 to 42 days the cultured chondrocytes were formed into a solid chondral graft, implanted at the damaged site of the talar dome and fixed with fibrin glue (Tissucol). RESULTS: Between July 2003 and October 2005 five patients, three males and two females, were treated using this method. Their age ranged from 22 to 46 years. Follow-up was 6 to 24 months, with an average of 12.6 months, and the patients were examined by MRI at 2 weeks, 2 and 6 months and at 1 year. The clinical results were evaluated on the basis of the Mazur and Weber scoring systems. CONCLUSIONS: A significant improvement in clinical function of the ankle joint was achieved in three patients and the condition remained unchanged in one patient. In one patient, the surgical outcome was too recent for evaluation, but the MRI results indicated tendency to good incorporation of the graft.


Asunto(s)
Traumatismos del Tobillo/cirugía , Articulación del Tobillo , Cartílago Articular/lesiones , Condrocitos/trasplante , Ingeniería de Tejidos , Adulto , Cartílago Articular/citología , Células Cultivadas , Condrocitos/citología , Femenino , Humanos , Masculino , Persona de Mediana Edad
6.
Cas Lek Cesk ; 145(9): 733-7, 2006.
Artículo en Checo | MEDLINE | ID: mdl-17091730

RESUMEN

BACKGROUND: Increasing number of seniors in the society requires more university-degree educated professionals--health care professionals, social care workers and managers with basic exposure to and knowledge of gerontology and geriatrics. The aim of our paper was to evaluate the effectiveness of undergraduate training of gerontology and geriatrics among students of the 1st Faculty of Medicine, Charles University in Prague. METHODS AND RESULTS: To get information about knowledge of medical students and students of ergotherapy and physiotherapy and about their attitudes towards senior citizens we conducted a survey using two anonymous questionnaires prepared in our department and piloted earlier. The survey ran during the academic year 2004/2005. Students completed identical questionnaires twice, first time before the start of the clinical rotation and second time after the training end (n=134). Evaluation of knowledge and attitudes confirmed that one to two weeks clinical rotation at Department of Geriatrics was effective and increased knowledge of students in the topic trained. The percentage of correct answers in all three evaluated training programmes increased after the completion of the clinical rotation and reached 83% and more. From 134 participating students, 54.5 % appreciated life experience and wisdom of seniors they met, 98.4 % of students were satisfied with the training programme and 67.2 % of students reported that after training they changed their attitude towards senior population. CONCLUSIONS: Our survey confirmed that clinical training in geriatric medicine at 1st Faculty of Medicine, Charles University in Prague, prepared in agreement with current European recommendations is sufficiently effective and well accepted by the students. Therefore we recommend introduction of formal geriatric training for students in all medical faculties in the Czech Republic.


Asunto(s)
Educación de Pregrado en Medicina , Geriatría/educación , República Checa , Evaluación Educacional , Humanos
7.
Acta Chir Orthop Traumatol Cech ; 73(6): 373-9, 2006 Dec.
Artículo en Checo | MEDLINE | ID: mdl-17266838

RESUMEN

PURPOSE OF THE STUDY: The aim of this study was to present the results of treatment of deep chondral defects of the patella by transplantation of a solid chondral graft formed by autologous cultured chondrocytes. MATERIAL AND METHODS: Indications for autologous chondrocyte implantation most frequently included acute trauma to the knee, particularly the patella, which resulted in a severe focal cartilage defect. The lesions were assessed on the basis of the Bessette and Hunter classification preoperatively, and on the Outerbridge classification during arthroscopy. A sample of healthy cartilage was harvested from a non-weight-bearing area of the trochlea femoris. After cultivation of chondrocytes for 28 to 42 days in the tissue bank, a solid chondral graft, prepared with the use of fibrin glue (Tissucol), was ready for implantation. RESULTS: Six patients, two males and four females (average age, 21.1 years; range, 13 to 39 years) were treated by this method in the period from July 2003 to October 2005. Follow-up ranged from 1 to 25 months, with an average of 18.5 months. The patients were examined postoperatively by magnetic resonance imaging (MRI) at 2 weeks, 2 and 6 months, and at 1 year. The clinical results were evaluated by the Meyers, the Tegner and the Lysholm knee scoring systems. Two of the six patients, in whom the follow-up period was shorter than 6 months, were not included in the evaluation. CONCLUSIONS: A significant improvement in knee function was recorded when the preoperative and final follow-up stages were compared, as well as on comparison with the healthy contralateral knee joint. MRI examination showed good graft incorporation in all patients.


Asunto(s)
Cartílago Articular/lesiones , Condrocitos/trasplante , Rótula/lesiones , Ingeniería de Tejidos , Adolescente , Adulto , Células Cultivadas , Femenino , Humanos , Masculino , Trasplante Autólogo
8.
Rozhl Chir ; 82(4): 179-84, 2003 Apr.
Artículo en Checo | MEDLINE | ID: mdl-12795228

RESUMEN

During the period from January 2000 to November 2001 the authors performed in 98 patients 129 drainages of pathological fluid collections. In all instances the drainages were performed under CT control. In 80 patients the drain was placed in the area of the pleural cavity, in 47 in the area of the peritoneal cavity and in three patients the localization was different. For drainage they used catheters of the pigtail type size from 8F to 24 F, depending on the extent of the pathological collection, its depth, and nature of the drained contents. In 119 cases Seldinger's method was used, in 10 the tandem troacar method of placement of drainage catheters. The placement of the drainage catheter under CT control is a safe and effective method for removal of pathological fluid collection. In the authors' group successful drainage was proved in 71 of 84 (84.5%) patients followed up on a long-term basis.


Asunto(s)
Drenaje/métodos , Radiografía Intervencional , Tomografía Computarizada por Rayos X , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Ascitis/terapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Derrame Pleural/terapia
9.
Vnitr Lek ; 47(7): 437-43, 2001 Jul.
Artículo en Checo | MEDLINE | ID: mdl-11505713

RESUMEN

In 18 patients with symptomatic hypertrophic obstructive cardiomyopathy 18 procedures involving percutaneous transluminal myocardial ablation were performed. The patients were followed up for three months after the procedure. The mean intraventricular peak gradient declined during the intervention from 51 +/- 26 mm Hg to 11 +/- 12.2 mm Hg (p < 0.001). On average 2.7 +/- 1.1 ml ethanol were administered, as a rule into the first septal branch. The target artery was detected in 13 instances by means of myocardial contrast echocardiography and in five instances by haemodynamic investigation. In one instance the procedure was combined with subsequent balloon angioplasty of the ramus circumflexus. In one patient it was necessary to implant ex post a permanent pacemaker on account of AV bloc grade III. In one instance when myocardial contrast echocardiography was not used) infarsation not only of the basal interventricular septum occurred but also of the posterolateral left ventricular wall. During the three-month follow-up the incidence of stenocardias assessed according to CCS declined from grade 2.6 +/- 0.8 to 0.8 +/- 0.8 (p < 0.0001). Dyspnoea evaluated according to NYHA declined from grade 2.9 +/- 0.5 to 1.4 +/- 0.6 (p < 0.0001). The maximal intraventricular gradient evaluated by Doppler echocardiography declined from 57.2 +/- 42 mm Hg before the procedure to 19.7 +/- 12 mm Hg (p < 0.001). An identical gradient after stimulation with one dose of isosorbide dinitrate spray (1.25 mg) declined from 82.3 +/- 27 mm Hg to 25 +/- 6 mm Hg (p < 0.0001). The diastolic thickness of the IVS in the intervened segment declined from 21.2 +/- 3 mm to 14.7 +/- 2 mm (p < 0.0001). No significant change in the size of the left ventricle was recorded, nor in its ejection fraction and size of the left atrium. One patient died suddenly during the follow up period. Percutaneous transluminal septal myocardial ablation leads during short-term follow-up to a significant weakening of the basal segment of the interventricular septum, a decline of the intraventricular gradient and symptomatology of hypertrophic obstructive cardiomyopathy.


Asunto(s)
Cardiomiopatía Hipertrófica/cirugía , Ablación por Catéter , Tabiques Cardíacos/cirugía , Adulto , Anciano , Cardiomiopatía Hipertrófica/complicaciones , Cardiomiopatía Hipertrófica/diagnóstico por imagen , Ecocardiografía Doppler , Electrocardiografía , Femenino , Bloqueo Cardíaco/complicaciones , Bloqueo Cardíaco/terapia , Humanos , Masculino , Persona de Mediana Edad , Radiografía Intervencional
10.
Arch Orthop Trauma Surg ; 121(1-2): 117-8, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11195109

RESUMEN

We present a case of a 15-year-old girl with osteoid osteoma in an unusual subchondral localization of the olecranon. Unspecific complaints and minimal X-ray findings at the onset of the disease led to an incorrect diagnosis and more than 2 years of inefficient treatment.


Asunto(s)
Neoplasias Óseas/diagnóstico , Articulación del Codo , Osteoma Osteoide/diagnóstico , Cúbito , Adolescente , Neoplasias Óseas/complicaciones , Neoplasias Óseas/fisiopatología , Neoplasias Óseas/cirugía , Femenino , Humanos , Imagen por Resonancia Magnética , Osteoma Osteoide/complicaciones , Osteoma Osteoide/fisiopatología , Osteoma Osteoide/cirugía , Osteotomía , Dolor/etiología , Pronación , Rango del Movimiento Articular , Reoperación , Supinación
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