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1.
Clin Transl Radiat Oncol ; 48: 100829, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39192878

RESUMEN

Background: The effectiveness of radiotherapy for pancreatic cancer is debated. Patient-derived organoids (PDOs) already mimicked clinical radiation response in other cancer types, which could be valuable in pancreatic cancer as well. This study aimed to investigate whether PDOs can be used to model RT response in pancreatic cancer and to explore the presence of a dose-response correlation. Methods: PDOs derived from two pancreatic cancer patients (HUB-08-B2-022A and HUB-08-B2-026B) were irradiated with doses ranging from 0 to 40 Gray. Viability assessments were conducted after seven and 10 days by measuring ATP-levels. Results were normalized, defining the viability at 0 Gray as 100 % and an absolute viability of 0 as 0 %. The relative area under the curve (rAUC) was calculated (0 = total sensitivity, 1 = total resistance). Results: With a readout time of seven days, both HUB-08-B2-022A and HUB-08-B2-026B exhibited viability above 50 % at the highest dose of 12 Gy (rAUC of 0.79 and 0.69, respectively). With a readout time of 10 days, both PDOs showed a dose-response relation although HUB-08-B2-022A was more sensitive than HUB-08-B2-026B (rAUC of 0.37 and 0.51, respectively). Increasing the radiation dose to 40 Gy did not further affect viability, but the dose-response relation remained present (rAUC of 0.13 and 0.26, respectively). In the final experiment with a readout time of 10 days and a maximum dose of 14 Gy, the dose-response correlation was paramount in both PDOs (rAUC 0.28 and 0.45, respectively), with HUB-08-B2-022A being most sensitive. Conclusions: In this setup, both pancreatic cancer PDOs showed an irradiation dose-response correlation. These preliminary findings suggest that pancreatic cancer PDOs are suitable for assessing radiation response in vitro. Further experiments are needed to eventually simulate treatment responses to personalized treatment strategies.

2.
Phys Med Biol ; 69(17)2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39053500

RESUMEN

To ensure the accuracy of radiation delivery to patients in a 1.5 T MRI-linac, the implementation of quality assurance (QA) devices compatible with MR technology is essential. The OCTAVIUS 4D MR, made by PTW (Freiburg, Germany) is designed to ensure consistent and ideal alignment of its detectors with the direction of each beam segment. This study focuses on investigating the fundamental characteristics of the detector response for the OCTAVIUS Detector (OD) 1500 MR and OCTAVIUS 1600 MR when used in the MR-compatible OCTAVIUS 4D. Characteristics examined included short-term reproducibility, dose linearity, field size dependency, monitor unit (MU) rate dependency, dose-per-pulse dependency, and angular dependency. The evaluation of OD 1500 MR also involved measuring 25 clinical treatment plans across diverse target sizes and anatomical sites, including the liver/pancreas, rectum, prostate, lungs, and lymph nodes. One plan was measured with the standard setup and with a 5 cm left offset. The OD 1600 MR was not available for these measurements. The capability of the OD 1500 MR to identify potential errors was assessed by introducing a MU and positional shift within the software. The results demonstrated no significant differences in short-term reproducibility (<0.2%), dose linearity (<1%), field size dependency (<0.7%for field sizes larger than 5 cm × 5 cm), MU rate dependency (<0.8%), dose-per-pulse dependency (<0.4%) and angular dependency (standard deviation<0.5%). All tests of clinical plans were successfully completed. The OD 1500 MR demonstrated compatibility with the standard 95% pass rate when employing a global 3%/3 mm gamma criterion, and a 90% pass rate using a global 2%/2 mm gamma criterion. The detector demonstrated the capacity to measure treatment plans with a 5 cm left offset. With the standard parameters, the gamma test was sensitive to position errors but required an addition tests of mean/median dose or point dose in order to detect small dose difference.


Asunto(s)
Imagen por Resonancia Magnética , Aceleradores de Partículas , Planificación de la Radioterapia Asistida por Computador , Imagen por Resonancia Magnética/instrumentación , Humanos , Planificación de la Radioterapia Asistida por Computador/métodos , Control de Calidad , Dosificación Radioterapéutica
3.
Phys Imaging Radiat Oncol ; 31: 100597, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39006756

RESUMEN

Current online adaptive radiotherapy (oART) workflows require dedicated equipment. Our aim was to develop and implement an oART workflow for a C-arm linac which can be performed using standard clinically available tools. A workflow was successfully developed and implemented. Three patients receiving palliative radiotherapy for bladder cancer were treated, with 33 of 35 total fractions being delivered with the cone-beam computed tomography (CBCT)-guided oART workflow. Average oART fraction duration was 24 min from start of CBCT acquisition to end of beam on. This work shows how oART could be performed without dedicated equipment, broadening oART availability for application at existing treatment machines.

4.
Comput Intell Neurosci ; 2019: 7876248, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31354802

RESUMEN

The vast majority of P300-based brain-computer interface (BCI) systems are based on the well-known P300 speller presented by Farwell and Donchin for communication purposes and an alternative to people with neuromuscular disabilities, such as impaired eye movement. The purpose of the present work is to study the effect of speller size on P300-based BCI usability, measured in terms of effectiveness, efficiency, and satisfaction under overt and covert attention conditions. To this end, twelve participants used three speller sizes under both attentional conditions to spell 12 symbols. The results indicated that the speller size had, in both attentional conditions, a significant influence on performance. In both conditions (covert and overt), the best performances were obtained with the small and medium speller sizes, both being the most effective. The speller size did not significantly affect workload on the three speller sizes. In contrast, covert attention condition produced very high workload due to the increased resources expended to complete the task. Regarding users' preferences, significant differences were obtained between speller sizes. The small speller size was considered as the most complex, the most stressful, the less comfortable, and the most tiring. The medium speller size was always considered in the medium rank, which is the speller size that was evaluated less frequently and, for each dimension, the worst one. In this sense, the medium and the large speller sizes were considered as the most satisfactory. Finally, the medium speller size was the one to which the three standard dimensions were collected: high effectiveness, high efficiency, and high satisfaction. This work demonstrates that the speller size is an important parameter to consider in improving the usability of P300 BCI for communication purposes. The obtained results showed that using the proposed medium speller size, performance and satisfaction could be improved.


Asunto(s)
Interfaces Cerebro-Computador , Equipos de Comunicación para Personas con Discapacidad , Potenciales Relacionados con Evento P300 , Movimientos Oculares , Adulto , Atención/fisiología , Encéfalo/fisiología , Interfaces Cerebro-Computador/psicología , Equipos de Comunicación para Personas con Discapacidad/psicología , Movimientos Oculares/fisiología , Fatiga/etiología , Femenino , Humanos , Masculino , Escritura , Adulto Joven
5.
Am J Gastroenterol ; 113(2): 265-272, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28809388

RESUMEN

OBJECTIVES: Few data are available to describe the changes in incidence of pediatric-onset inflammatory bowel disease (IBD). The aim of this study was to describe changes in incidence and phenotypic presentation of pediatric-onset IBD in northern France during a 24-year period. METHODS: Pediatric-onset IBD (<17 years) was issued from a population-based IBD study in France between 1988 and 2011. Age groups and digestive location were defined according to the Paris classification. RESULTS: 1,350 incident cases were recorded (8.3% of all IBD) including 990 Crohn's disease (CD), 326 ulcerative colitis (UC) and 34 IBD unclassified (IBDU). Median age at diagnosis was similar in CD (14.4 years (Q1=11.8-Q3=16.0)) and UC (14.0 years (11.0-16.0)) and did not change over time. There were significantly more males with CD (females/males=0.82) than UC (females/males=1.25) (P=0.0042). Median time between onset of symptoms and IBD diagnosis was consistently 3 months (1-6). Mean incidence was 4.4/105 for IBD overall (3.2 for CD, 1.1 for UC and 0.1 for IBDU). From 1988-1990 to 2009-2011, a dramatic increase in incidences of both CD and UC were observed in adolescents (10-16 years): for CD from 4.2 to 9.5/105 (+126%; P<0.001) and for UC, from 1.6 to 4.1/105 (+156%; P<0.001). No modification in age or location at diagnosis was observed in either CD or UC. CONCLUSIONS: In this population-based study, CD and UC incidences increased dramatically in adolescents across a 24-year span, suggesting that one or more strong environmental factors may predispose this population to IBD.


Asunto(s)
Colitis Ulcerosa/epidemiología , Enfermedad de Crohn/epidemiología , Adolescente , Niño , Femenino , Francia/epidemiología , Humanos , Incidencia , Enfermedades Inflamatorias del Intestino/epidemiología , Masculino
6.
Phys Rev E ; 96(4-1): 043205, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29347625

RESUMEN

We describe a model for the study of the interaction of short x-ray free-electron laser (XFEL) pulses with large finite samples. Hydrodynamics is solved in one-dimensional planar geometry with consideration of the electron-ion energy exchange and of the possible elastoplastic behavior. From a time-dependent calculation of the complex refractive index and of the underlying atomic physics, XFEL energy deposition is modeled through a calculation of the radiation field in the material. In the case of hard x-ray irradiation, energetic electrons induced by the XFEL absorption can propagate and deposit their energy outside the interaction region. Simulations of the interaction of hard x-ray ultrashort pulses with solid materials Ru and Si at different grazing incidence angles are presented and discussed. The results obtained demonstrate the potential of this approach to predict damage dynamics for materials of interest for x-ray optics.

7.
J Anim Sci ; 91(2): 588-604, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23148259

RESUMEN

The mule duck, an interspecific hybrid obtained by crossing common duck (Anas platyrhynchos) females with Muscovy (Cairina moschata) drakes, is widely used for fatty liver production. The purpose of the present study was to detect and map single and pleiotropic QTL that segregate in the common duck species, and influence the expression of traits in their overfed mule duck offspring. To this end, we generated a common duck backcross (BC) population by crossing Kaiya and heavy Pekin experimental lines, which differ notably in regard to the BW and overfeeding ability of their mule progeny. The BC females were mated to Muscovy drakes and, on average, 4 male mule ducks hatched per BC female (1600 in total) and were measured for growth, metabolism during growth and the overfeeding period, overfeeding ability, and the quality of their breast meat and fatty liver. The phenotypic value of BC females was estimated for each trait by assigning to each female the mean value of the phenotypes of her offspring. Estimations allowed for variance, which depended on the number of male offspring per BC and the heritability of the trait considered. The genetic map used for QTL detection consisted of 91 microsatellite markers aggregated into 16 linkage groups (LG) covering a total of 778 cM. Twenty-two QTL were found to be significant at the 1% chromosome-wide threshold level using the single-trait detection option of the QTLMap software. Most of the QTL detected were related to the quality of breast meat and fatty liver: QTL for meat pH 20 min post mortem were mapped to LG4 (at the 1% genome-wide significance level), and QTL for meat lipid content and cooking losses were mapped to LG2a. The QTL related to fatty liver weight and liver protein and lipid content were for the most part detected on LG2c and LG9. Multitrait analysis highlighted the pleiotropic effects of QTL in these chromosome regions. Apart from the strong QTL for plasma triglyceride content at the end of the overfeeding period mapped to chromosome Z using single-trait analysis, all metabolic trait QTL were detected with the multitrait approach: the QTL mapped to LG14 and LG21 affected the plasma cholesterol and triglyceride contents, whereas the QTL mapped to LG2a seemed to impact glycemia and the basal plasma corticosterone content. A greater density genetic map will be needed to further fine map the QTL.


Asunto(s)
Crianza de Animales Domésticos/métodos , Cruzamientos Genéticos , Hígado/fisiología , Carne/normas , Alimentación Animal , Animales , Dieta/veterinaria , Patos/genética , Femenino , Ligamiento Genético , Genotipo , Masculino , Repeticiones de Microsatélite , Sitios de Carácter Cuantitativo , Factores Sexuales
8.
Rev Port Pneumol ; 18(5): 239-43, 2012.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-22609057

RESUMEN

INTRODUCTION: Diabetes mellitus (DM) is a risk factor for tuberculosis (TB) and may modify its presenting features. The aim of this study was to find out the influence of DM on clinical, radiological and treatment features of TB in hospitalized patients. MATERIAL AND METHODS: In a retrospective study we reviewed the records of 123 patients with TB and DM admitted from 2000 to 2008 and compared this group with another one of 123 patients with TB without DM. RESULTS: Although in both groups multilobar lung lesions predominated, there were more cases of isolated lower lung field (LLF) involvement in diabetics than in nondiabetics (10.6% vs 3.3% p=0.03). Cavitary lesions were less frequent (63.4% vs 82.1% p=0.01) and extra-pulmonary TB manifestations were more frequent (28.5% vs 16.3% p=0.02) in diabetics than in nondiabetics. There were no significant differences between groups regarding multidrug resistant - TB (MDR-TB) and adverse effects of anti-tuberculosis drugs. The in-hospital mortality was higher in diabetics (8.1% vs 0.8% p=0.01), but using a binary logistic regression there was significant difference in mortality only in respect to the variable MDR-TB. CONCLUSIONS: This study showed that DM affected some clinical and radiological presenting features in hospitalized TB patients. LLF involvement and extra-pulmonary TB manifestations were more frequent in diabetic patients than in nondiabetic ones.


Asunto(s)
Complicaciones de la Diabetes/diagnóstico , Tuberculosis Pulmonar/diagnóstico , Adulto , Complicaciones de la Diabetes/tratamiento farmacológico , Femenino , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tuberculosis Pulmonar/tratamiento farmacológico
9.
Clin Chem Lab Med ; 49(11): 1837-43, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21801029

RESUMEN

BACKGROUND: Many labs have not yet selected the most appropriate Westgard Quality Control (QC) rule for each test. This is mainly due to the apparent complexity of the matter. METHODS: From the Westgard OPSpecs Charts QC planning tool and the Sigma Metrics formula's it was deduced that every Westgard rule has its own Sigma value. This was converted to an easy three-step road map to optimal Westgard QC rules. RESULTS: The road map provided is based on Sigma Metrics that hold a definition of "world class quality", at which no further effort to increase quality needs to be taken. Furthermore, it is shown that clinical chemical tests can be classified as "good": quality at or above world class, "bad": quality below world class but controllable with Westgard QC rules and "ugly": quality not controllable with Westgard QC rules alone. Finally, practical tips of how to deal with this and related aspects are given. CONCLUSIONS: The use of the road map based on Sigma Metrics leads to fast and easy implementation of optimal Westgard QC rules.


Asunto(s)
Biomarcadores , Química Clínica/métodos , Interpretación Estadística de Datos , Laboratorios/normas , Programas Informáticos , Biomarcadores/sangre , Biomarcadores/orina , Humanos , Control de Calidad , Estudios de Validación como Asunto
10.
Scand J Prim Health Care ; 28(1): 18-23, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20121652

RESUMEN

OBJECTIVE: Laboratory tests are ordered on a daily basis, even though disease probability is often very low. Abnormal results, especially mildly abnormal results, can be difficult to interpret in these circumstances. Further insights into the occurrence of abnormalities can help improve rational test ordering and test interpretation. The objective was therefore to examine the frequency of mildly and markedly abnormal results and their relationship with physicians' reasons for ordering tests. DESIGN: Prospective study. Participants. A total of 87 primary care physicians in the Netherlands collected data on 1775 patients. MAIN OUTCOME MEASURES: The physicians recorded the reason for ordering the tests, the most probable diagnosis and the pretest probability. The laboratories' reference values and specified "action limits" were used to assess the number of abnormal results and markedly abnormal results, respectively. RESULTS: Laboratory results were received for 1621 patients and 15,603 tests were reported (mean 9.6). The proportion of abnormal test results increased with increasing pretest probability (from 13.9% to 34.7%) and was 13.4% for tests ordered to reassure the patient and 13.3% for psychosocial diagnoses. The proportion of patients with at least one abnormal test result was high: 53.1% for tests ordered to reassure and 57.7% in patients with low pretest probability. Corresponding values for a marked abnormality were 11.1% and 12.4%, respectively. CONCLUSION: Abnormal laboratory test results were frequent, even when pretest probability was low. Physicians should therefore carefully consider when tests are necessary. Future research could explore physicians' interpretation of test results and its impact on diagnosis and management.


Asunto(s)
Pruebas de Química Clínica/estadística & datos numéricos , Diagnóstico , Laboratorios/estadística & datos numéricos , Pruebas de Química Clínica/normas , Toma de Decisiones , Medicina Familiar y Comunitaria , Humanos , Laboratorios/normas , Países Bajos , Pautas de la Práctica en Medicina , Valor Predictivo de las Pruebas , Atención Primaria de Salud , Estudios Prospectivos , Valores de Referencia
11.
Arch Pediatr ; 17(2): 149-53, 2010 Feb.
Artículo en Francés | MEDLINE | ID: mdl-19945260

RESUMEN

Granulocytic sarcoma (GS) is a rare extramedullary tumor frequently associated with acute myeloblastic leukemia (AML). We report 3 cases of pediatric granulocytic sarcomas with various locations: skin, orbit, and bowel. Cases 1 and 2 were associated with AML; case 3 was isolated. In all 3 cases, the diagnosis was delayed or initially missed. Pathology and immunohistochemistry data identified the disease. GS is treated with chemotherapy, like AML. The prognosis of GS seems better than that of isolated AML.


Asunto(s)
Neoplasias Faciales/diagnóstico , Neoplasias Intestinales/diagnóstico , Intestino Delgado , Leucemia Mieloide Aguda/diagnóstico , Neoplasias Primarias Múltiples/diagnóstico , Neoplasias Orbitales/diagnóstico , Sarcoma Mieloide/diagnóstico , Neoplasias Cutáneas/diagnóstico , Protocolos de Quimioterapia Combinada Antineoplásica , Biopsia , Médula Ósea/patología , Trasplante de Médula Ósea , Preescolar , Terapia Combinada , Errores Diagnósticos , Neoplasias Faciales/tratamiento farmacológico , Neoplasias Faciales/patología , Femenino , Estudios de Seguimiento , Humanos , Lactante , Neoplasias Intestinales/tratamiento farmacológico , Neoplasias Intestinales/patología , Leucemia Bifenotípica Aguda/diagnóstico , Leucemia Bifenotípica Aguda/tratamiento farmacológico , Leucemia Bifenotípica Aguda/patología , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/patología , Masculino , Neoplasias Primarias Múltiples/tratamiento farmacológico , Neoplasias Primarias Múltiples/patología , Neoplasias Orbitales/tratamiento farmacológico , Neoplasias Orbitales/patología , Sarcoma Mieloide/tratamiento farmacológico , Sarcoma Mieloide/patología , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/patología , Tomografía Computarizada por Rayos X
12.
J Phys Condens Matter ; 22(34): 345003, 2010 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-21403247

RESUMEN

We present an experimental study of the evolution of the surface of a growing film as a function of the statistical parameters of the virgin substrate roughness. The growth of sputter-deposited Al(2)O(3) films onto Si substrates was followed in situ using an x-ray scattering technique. Despite the use of substrates presenting different roughness correlation length and crystallographic orientation, the evolution of the film roughness is demonstrated to obey the same scaling law, i.e., with the same static and dynamic exponents. Approaches to accurately determine the scaling exponents from x-ray scattering data are discussed.

13.
Ann Phys Rehabil Med ; 52(5): 374-81, 2009 Jun.
Artículo en Inglés, Francés | MEDLINE | ID: mdl-19541559

RESUMEN

OBJECTIVES: Retrospective analysis of the efficiency of a protocol for care of chronic vegetative states (CVS) and minimally conscious state (MCS) in Lorraine. MATERIAL AND METHOD: Two indicators are used: protocol activity (number of patients hospitalized between 1988 and 2006, number of admissions per year, of requests per year, origin of requests, waiting time) and the epidemiological data (age, sex ratio, etiology, length of stay, geographic origin, number of deaths, number of hospital discharges). The number of CVS and MCS and patients having progressed towards arousal is specified as well as the technical procedures (orthopedic surgery, number of tracheotomies). RESULTS: Forty-seven patients (30 males and 17 females) were hospitalized in a 12-bed unit. The number of admissions per year was 2.4, and the annual number of requests varied between five and 15. Hospitalization times ranged from six to 18 months. The average length of hospitalization was 41 months. Eighty-eight percent of the cases were residents of Lorraine. The etiology was traumatic (53%), vascular (38% including 12% anoxia), miscellaneous (9%). Fifteen percent rate of return to arousal (average time period: 28.41 months, traumatic etiology) with hospital discharge in four cases. CONCLUSION: The protocol is managed as part of a local scheme and enables an appropriate response to a specific clinical profile by providing up-to-date multidiscipline follow-up care and a rapid solution should intercurrent events occur (signs of arousal, orthopedic deterioration, change of environment). Typical limitations are geographical remoteness and difficulties with family support care.


Asunto(s)
Protocolos Clínicos , Cuidados a Largo Plazo , Estado Vegetativo Persistente/terapia , Actividades Cotidianas , Adulto , Nivel de Alerta , Daño Encefálico Crónico/rehabilitación , Femenino , Francia/epidemiología , Humanos , Trastornos del Lenguaje/etiología , Trastornos del Lenguaje/rehabilitación , Esperanza de Vida , Cuidados a Largo Plazo/métodos , Cuidados a Largo Plazo/estadística & datos numéricos , Masculino , Grupo de Atención al Paciente , Estado Vegetativo Persistente/diagnóstico , Estado Vegetativo Persistente/epidemiología , Estado Vegetativo Persistente/rehabilitación , Autonomía Personal , Recuperación de la Función , Estudios Retrospectivos , Adulto Joven
14.
J Biomech ; 41(14): 2926-31, 2008 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-18771768

RESUMEN

Hip dynamics in the intact limb during the beginning of stance phase in unilateral trans-tibial amputees (TTA) was studied to evaluate its contribution to compensatory function. We hypothesized (1) an increase in hip total work during H1 power phase (0-30% of gait cycle) including an initial negative phase and (2) an intensification of the hip work in response to uncomfortable gait induced by prosthesis misalignment. Three-dimensional gait analysis was conducted in 17 unilateral TTA and 15 healthy subjects walking at the same self-selected speed in three prosthetic alignments: initial alignment (IA); IA altered either by 6 degrees of internal rotation (IR) or by 6 degrees of external rotation. Patients reported best comfort of gait in IA condition and discomfort mainly in IR condition. During the H1 power phase, in intact limbs a consistent initial flexion movement of the hip (0-8% gait cycle) was associated to negative work and was followed by hip extension and positive work whereas in both prosthetic and control limbs only hip extension and positive work occurred (except in one healthy individual). Absolute value of hip work during H1 phase was significantly higher in intact and prosthetic limbs compared to control limbs in IA condition and was further significantly increased in IR condition only in intact limbs demonstrating a compensatory function of the latter. In intact limbs, early hip negative work contributed to energy absorption in addition to the knee joint probably to compensate the lower energy absorption exerted by the prosthetic limbs.


Asunto(s)
Amputados/rehabilitación , Miembros Artificiales , Marcha , Articulación de la Cadera/fisiopatología , Articulación de la Rodilla/fisiopatología , Pierna/fisiopatología , Rango del Movimiento Articular , Adaptación Fisiológica , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Tibia/fisiopatología , Caminata , Adulto Joven
15.
Ann Readapt Med Phys ; 51(3): 218-27, 2008 Apr.
Artículo en Francés | MEDLINE | ID: mdl-18358554

RESUMEN

OBJECTIVE: The objective of this article is to review anatomical, histological and physiological muscle changes following below-knee amputation. MATERIALS AND METHODS: We searched the PubMed and Reedoc databases for studies evaluating modifications of the below-knee stump and changes over time in its anatomy, volume and histology. We also looked at postamputation modifications in gait and balance. RESULTS: Below-knee amputees show muscular atrophy on both the amputated side and nonamputated side, with fewer and smaller muscle fibres (particularly slow-twitch fibres). This amyotrophy varies in magnitude and distribution and can reach about 25% for the quadriceps (predominantly on the medial side), but is nonsignificant for the hamstrings. This amyotrophy results from the anatomical consequences of the surgical act. The loss of one or more of a muscle's insertions or reimplantation into a nonphysiological site prompts greater atrophy. Changes in muscle activation patterns also lead to atrophy. The hamstrings replace the triceps as the main muscles for propulsion and the remaining stump muscles contract so as to ensure a good fit with the prosthesis. The below-knee amputee must adapt to a new muscular state: gait symmetry is altered, energy expenditure for walking is higher and training is needed in order to achieve optimal balance control.


Asunto(s)
Amputados , Músculo Esquelético/patología , Músculo Esquelético/fisiopatología , Adaptación Fisiológica , Marcha/fisiología , Humanos , Pierna , Imagen por Resonancia Magnética , Atrofia Muscular/fisiopatología , Tomografía Computarizada por Rayos X
16.
Arch Pediatr ; 15(3): 275-8, 2008 Mar.
Artículo en Francés | MEDLINE | ID: mdl-18321687

RESUMEN

Nocardiosis is a rare infectious disease in children. We report here a disseminated nocardiosis in a child with acute lymphoblastic leukemia. The patient presented prolonged febrile neutropenia and nodular pneumopathy. Based on the amplification of a 16S rDNA, a PCR assay detected Nocardia sp. in the patient's bronchoalveolar lavage (BAL) fluid. Culture of BAL samples yielded Nocardia nova colonies after 2 weeks of incubation. Hepatic, splenic, renal and cerebral localisations were detected on extension checkup. trimethoprime-sulfamethoxazole and amikacine were started given the results of PCR assay, with a good response. Improvement of the patient's general condition led to complete chemotherapy under ciprofloxacine and ceftriaxone treatment, without nocardiosis reactivation. Nocardiosis is a rare complication in children with acute lymphoblastic leukemia. trimethoprime-sulfamethoxazole prophylaxis is widely used to prevent Pneumocystis jiroveci infection in children with haematologic malignancies. As Nocardia species are usually sensible, trimethoprime-sulfamethoxazole could play a role in Nocardia prophylaxis in such population. In our patient, compliance with trimethoprime-sulfamethoxazole had been low. Nocardia species are relatively fastidious growth bacteria and are difficult to isolate with classical bacteriological techniques. Molecular methods are now available, with a good sensitivity and fast results allowing to start an appropriate antibiotherapy before culture results, as early treatment is a major prognosis factor in nocardiosis. Nocardia infection should be suspected in case of nodular pneumopathy in immunocompromised children. An extension checkup should be performed to detect secondary localisations.


Asunto(s)
Nocardiosis/complicaciones , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicaciones , Adolescente , Antibacterianos/uso terapéutico , Líquido del Lavado Bronquioalveolar , Quimioterapia Combinada , Humanos , Imagen por Resonancia Magnética , Masculino , Nocardiosis/diagnóstico por imagen , Nocardiosis/patología , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico por imagen , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Radiografía
17.
Gait Posture ; 28(2): 278-84, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18295487

RESUMEN

This study evaluated the asymmetry of knee kinetics during uncomfortable gait induced by prosthesis misalignment to further demonstrate the compensatory function of the knee joint of the intact limb during gait. Three-dimensional gait analysis including knee kinematics and kinetics at the beginning of stance phase was conducted in 15 healthy subjects and 17 unilateral trans-tibial amputees (TTA) walking at self-selected speed in three conditions of prosthetic alignment: initial alignment (IA); initial alignment altered either by 6 degrees of internal rotation (IR) or by 6 degrees of external rotation (ER) applied on the pylon. Patients reported best comfort of gait in IA condition and discomfort mainly in IR condition. Maximum knee flexion and knee total work at power phases K0-K2 were significantly higher in intact limbs compared to prosthetic and control limbs. In intact limbs, these variables had significantly higher values (+10-35%, p<0.05) in IR condition than IA condition whereas these were not altered across conditions in prosthetic limbs. In trans-tibial amputees, inducing uncomfortable gait by internally rotating the prosthetic foot did not alter the knee kinetics of the prosthetic limb, which suggests a protective mechanism. Knee kinetics of the intact limb did alter, which suggests a compensatory mechanism.


Asunto(s)
Amputados , Marcha/fisiología , Articulación de la Rodilla/fisiología , Miembros Artificiales , Fenómenos Biomecánicos , Humanos , Cinética , Pierna
18.
Ann Readapt Med Phys ; 51(1): 50-6, 2008 Jan.
Artículo en Francés | MEDLINE | ID: mdl-18164090

RESUMEN

Lower limb amputee have lower exercise capacities, proportionally to the delay necessary to use their well-fitted prosthesis. Exercise training is a valid therapeutic to improve local factors (residual limb), muscle strength and endurance, locomotor performance and to decrease the cardiovascular risk factors. The programs for exercise training used for amputees are derivate from the vascular diseases and adapted (upper limb ergometer, cycloergometer with intact limb, pharmacological stress). Exercise training must be personalised because the population with lower limb amputation is very heterogeneous for deficiency and capacity (orthopaedic, vascular and cardiac) and for their socioprofessional project.


Asunto(s)
Amputados/rehabilitación , Ejercicio Físico , Extremidad Inferior/fisiología , Humanos
19.
Comp Biochem Physiol A Mol Integr Physiol ; 148(4): 899-902, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17950017

RESUMEN

The lipoprotein-lipase (LPL) hydrolyses the triacylglycerols (TG) secreted by the liver and, thus, allows the storage of lipids onto the extrahepatic tissues. The LPL activity has been studied by injection of LPL antibodies in three genotypes of ducks (Muscovy (Cairina moschat), Pekin (Anas plathyrhynchos) and Mule (hybrids of male Muscovy ducks and female Pekin ducks)) under overfeeding condition. The results show a similar weight gain between injected and control animals. A higher liver steatosis is observed in Mule ducks (616+/-18 g; 8.79% of body mass (BW)) and Muscovy ducks (514+/-13 g; 7.05% BW) compared to Pekin ducks (353+/-21 g; 5.89% BW, p<0.05). Pekin ducks showed a much marked extrahepatic fattening of abdominal and subcutaneous adipose tissues. The LPL activity was evaluated by comparing the evolution of the plasma TG concentrations after injections of saline (control animals) or injections of specific LPL-antibodies. Inhibition of LPL activity performed by intravenous injections of LPL-antibodies showed a spectacular increase in the plasma TG concentrations in the three genotypes. That increase was considerably higher in Pekin ducks (98+/-10 g/L) compared to Muscovy ducks (35+/-2 g/L, p<0.01) and Mule ducks (30+/-4 g/L, p<0.01). Those data suggest that a high export of lipids synthesized in liver and a high LPL activity occur in overfed Pekin ducks, which can favour the extrahepatic fattening to the detriment of the liver steatosis, and conversely in overfed Muscovy and Mule ducks.


Asunto(s)
Patos/genética , Lípidos/química , Lipoproteína Lipasa/metabolismo , Triglicéridos/sangre , Tejido Adiposo/metabolismo , Alimentación Animal , Ciencias de la Nutrición Animal , Animales , Composición Corporal , Peso Corporal , Femenino , Genotipo , Metabolismo de los Lípidos , Masculino , Especificidad de la Especie
20.
Lupus ; 16(2): 95-100, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17402365

RESUMEN

Genetic determinants taking part in the development of systemic lupus erythematosus (SLE) are complex and not fully characterized. Dysregulated expression of genes involved in the control of apoptosis has been previously suggested. We report here a consanguineous family with SLE manifestations in three siblings associated in one of them with severe lymphoproliferative features. Laboratory studies showed no defect in CD95-mediated cell death. Screening expression of Bcl-2 family genes that regulate mitochondrial apoptosis pathway showed an overexpression of the antiapoptotic Bfl-1 gene. Real time RT-PCR analysis indicated that overexpression of Bfl-1 was restricted to B-cells, with normal expression in T-cells. Those results suggest that overexpression of Bfl-1 could result in impaired B-lymphocyte homeostasis and inappropriate immune response leading to autoimmune manifestations.


Asunto(s)
Linfocitos B , Lupus Eritematoso Sistémico/genética , Proteínas Proto-Oncogénicas c-bcl-2/genética , Linfocitos B/inmunología , Niño , Preescolar , Femenino , Regulación de la Expresión Génica , Humanos , Masculino , Antígenos de Histocompatibilidad Menor , Linaje , Proteínas Proto-Oncogénicas c-bcl-2/biosíntesis
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