RESUMEN
JUSTIFICACIÓN: el ejercicio físico y el deporte se acompaña, especialmente si la actividad física se orienta a la ganancia de masa muscular, del consumo de suplementos proteicos. A nivel global se observa un incremento y diversificación en la comercialización y el consumo de suplementos proteicos que invita a evaluar su calidad y la conformidad de su etiquetado e información al consumidor.OBJETIVOS: determinar el contenido de proteínas en suplementos proteicos y verificar su conformidad con los valores declarados por el fabricante en el etiquetado.MATERIAL Y MÉTODOS: el contenido proteico de 19 muestras de suplementos proteicos (47,4 % adquiridas en tiendas de deporte. 31,6 % en gimnasios, 10,5 % en herbolarios y 10,5 % en tiendas online) de 11 marcas diferentes y de 4 tipo de proteína (suero 73,7 %, suero y huevo 10,5 %, guisante 5,3 %, guisante y arroz 10,5 %) y con origen europeo (89 %) y extracomunitario (UK 11 %) fue analizado mediante el método Kjeldahl.RESULTADOS/DISCUSIÓN: el contenido medio de proteínas en los complementos proteicos analizados oscila entre 19,47 - 91,57 g/100 g producto. 3 muestras (16%), todas ellas de origen animal extraídas del suero, cumplían o incluso superaban la cantidad de proteínas indicada en la etiqueta del producto. 4 muestras (21 %) presentaron una conformidad superior al 90 % entre el contenido real y declarado de proteínas. 12 muestras (63 %) registraron una diferencia por defecto de más de 10 g de proteína respecto al etiquetado lo que supone un porcentaje de conformidad entre la concentración proteica real y la declarada en el etiquetado por el fabricante del 40 88 % lo que revela la variabilidad y cuestiona la calidad de estos productos. Además, la falta de conformidad en el contenido proteico puede derivar en una ingesta de proteínas inferior a la prevista por el consumidor. (AU)
Asunto(s)
Humanos , Ejercicio Físico , Centros de Acondicionamiento , Proteínas , Suplementos DietéticosRESUMEN
The paper is concerned with the consensus problem in a multi-agent system such that each agent has boundary constraints. Classical Olfati-Saber's consensus algorithm converges to the same value of the consensus variable, and all the agents reach the same value. These algorithms find an equality solution. However, what happens when this equality solution is out of the range of some of the agents? In this case, this solution is not adequate for the proposed problem. In this paper, we propose a new kind of algorithms called supportive consensus where some agents of the network can compensate for the lack of capacity of other agents to reach the average value, and so obtain an acceptable solution for the proposed problem. Supportive consensus finds an equity solution. In the rest of the paper, we define the supportive consensus, analyze and demonstrate the network's capacity to compensate out of boundaries agents, propose different supportive consensus algorithms, and finally, provide some simulations to show the performance of the proposed algorithms.
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Algoritmos , Inteligencia Artificial , Consenso , Modelos EstadísticosRESUMEN
This paper presents the extension of a meta-model (MAM5) and a framework based on the model (JaCalIVE) for developing intelligent virtual environments. The goal of this extension is to develop augmented mirror worlds that represent a real and virtual world coupled, so that the virtual world not only reflects the real one, but also complements it. A new component called a smart resource artifact, that enables modelling and developing devices to access the real physical world, and a human in the loop agent to place a human in the system have been included in the meta-model and framework. The proposed extension of MAM5 has been tested by simulating a light control system where agents can access both virtual and real sensor/actuators through the smart resources developed. The results show that the use of real environment interactive elements (smart resource artifacts) in agent-based simulations allows to minimize the error between simulated and real system.
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Ambiente , Modelos Teóricos , Programas Informáticos , Artefactos , Humanos , Lenguajes de ProgramaciónRESUMEN
Plasma holotranscobalamin (holoTC) transports active cobalamin. Decreased levels of holoTC have been considered to be the earliest marker of cobalamin (Cbl) deficiency. In this work, holoTC was evaluated in low or borderline serum Cbl (LB12) and a concordance analysis was carried out with methylmalonic acid (MMA) and homocysteine (Hcy). Levels of Cbl, holoTC, MMA, and Hcy were investigated in a reference group in 106 patients with LB12 (≤200 pmol/l) and in 27 with folate deficiency (FOL). HoloTC levels were evaluated by an automated immunoassay (Active B12, Abbott Lab, Abbott Park, IL, USA). Lower levels of holoTC were observed in both LB12 and FOL groups (reference group vs LB12; p < 0.0001. Reference group vs FOL; p = 0.002). HoloTC levels were lower in LB12 than in FOL (p = 0.001). In LB12, concordance between Hcy and MMA was 82.1 % (chi-square test, p < 0.001; Kappa Index, 0.64, p < 0.0001). Concordance between Hcy and holoTC was 62 % (chi-square test, p = 0.006; Kappa index, 0.245, p = 0.006). Concordance between holoTC and MMA was 55.6 % (p = 0.233). Some cases with LB12 and elevated MMA did not show decreased holoTC. By contrast, MMA and Hcy were not increased in some patients with low holoTC and LB12. In conclusion, levels of holoTC were decreased in LB12 and FOL. In LB12 patients, holoTC concordance with MMA was poor. MMA/Hcy levels were not increased in a significant number of subjects with LB12 and low holoTC. This profile was found in iron deficiency. The significance of these changes remains to be clarified.
Asunto(s)
Homocisteína/sangre , Ácido Metilmalónico/sangre , Transcobalaminas/metabolismo , Deficiencia de Vitamina B 12/sangre , Deficiencia de Vitamina B 12/diagnóstico , Vitamina B 12/sangre , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
Introducción y objetivos: La conveniencia del implante de stent en lesiones carotídeas suboclusivas es un tema controvertido. Nuestro trabajo valoró las implicaciones clínicas y de procedimiento de la revascularización de lesiones carotídeas suboclusivas. Métodos: Se incluyó a 205 pacientes con enfermedad carotídea revascularizados con stent: los pacientes con lesiones suboclusivas (n = 54) fueron comparados con el resto de la población (n = 151). Resultados: No hubo diferencias entre grupos para la edad, el sexo y la tasa de pacientes sintomáticos (que constituían 3 cuartas partes de la población). El implante de stent en lesiones suboclusivas cursó con una alta tasa de éxito (96%), similar al resto de las lesiones (98%). La revascularización de las lesiones suboclusivas condicionó un mayor uso de protección proximal (54% vs. 20,5%, p < 0,001) y necesidad de predilatación (33% vs. 17%, p = 0,01). El abordaje de lesiones suboclusivas ocasionó un mayor desprendimiento de placa, manifestado por una mayor tasa de material embólico extraído (18,5% vs. 7%, p = 0,01) y de lesiones isquémicas cerebrales periprocedimiento (47% vs. 31%, p = 0,07). A los 30 días de la revascularización, la tasa de eventos neurológicos (muerte, ictus mayor, ictus menor) mostró tendencia a ser mayor para el grupo con lesiones suboclusivas (9,2% vs. 3,2%, p = 0,08). Conclusiones: La revascularización con stent de lesiones carotídeas suboclusivas presenta una alta tasa de éxito de procedimiento; sin embargo, su mayor carga de placa ocasiona un superior porcentaje de lesiones isquémicas cerebrales, y de eventos neurovasculares en el primer mes (AU)
Introduction and objectives: The advisability of implanting a stent in carotid near-occlusion stenosis is a controversial topic. We have assessed procedural and clinical implications of stent implantation for carotid artery disease with near occlusion. Methods: We included 205 patients who underwent carotid artery revascularisation with a stent. The group of patients with near-occlusion stenosis (n=54)was compared to the rest of the population (n=151). Results: No differences were found between groups for age, sex, and the percentage of symptomatic patients (three-quarters of the population). Carotid stent revascularisation for near-occlusion stenosis presented a high procedural success rate (96%) similar to that of revascularisation processes for other lesions (98%). Stenting in cases of near-occlusion stenosis required increased use of proximal protection (54% vs. 20.5%, P<.001) and predilation (33% vs. 17%, P=.01). The process to repair near-occlusion stenosis cause increased detachment of plaque, as shown by higher percentages of macroscopic plaque captured by protection devices (18.5% vs. 7%, P=.01) and of perioperative ischaemic brain lesions (47% vs 31%, P = .07). At 30 days of follow-up, the tendency toward adverse neurological events (death, major and minor stroke) was higher in the near-occlusion group (9.2% vs. 3.2%, P=.08). Conclusions: Stent revascularisation for near-occlusion carotid stenosis has a high procedural success rate; however, its higher plaque load was responsible for the increased rate of ischaemic brain lesions and adverse neurovascular events at 30 days post-procedure (AU)
Asunto(s)
Humanos , Estenosis Carotídea/cirugía , Procedimientos Endovasculares/métodos , Revascularización Cerebral/métodos , Infarto Cerebral/cirugía , StentsRESUMEN
Biliary cirrhosis produced by Campula spp. is described in 1 striped dolphin Stenella coeruleoalba and 4 harbour porpoises Phocoena phocoena. The hepatic lesions consisted of severe proliferation of fibrous connective tissue with loss of the lobular pattern, nodular regeneration of the hepatic tissue, bile duct hyperplasia and severe inflammatory infiltrate composed of eosinophils, macrophages, lymphocytes and plasma cells. These lesions were associated with severe infestation by Campula spp. Although inflammatory and degenerative hepatic lesions are frequently found in stranded dolphins, biliary cirrhosis has not been previously reported in cetaceans. Massive infestation by these parasites should be included as a cause of hepatic failure resulting in stranding of marine mammals.
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Delfines , Cirrosis Hepática Biliar/veterinaria , Marsopas , Trematodos/aislamiento & purificación , Infecciones por Trematodos/veterinaria , Animales , Cirrosis Hepática Biliar/microbiología , Trematodos/ultraestructura , Infecciones por Trematodos/parasitología , Infecciones por Trematodos/patologíaRESUMEN
This paper describes the immunophenotype of cellular inflammatory infiltrates in chronic cholangitis in six common dolphins (Delphinus delphis), four striped dolphins (Stenella coeruleoalba), three Atlantic spotted dolphins (Stenella frontalis) and one pygmy sperm whale (Kogia Breviceps) found stranded along the coasts of the Canary Islands (Spain). A panel of 5 antibodies previously tested in dolphins (anti-CD3, -IgG, -MHC class II, -S100 protein and -lysozyme) were used. The present work also reports cross reactivity with dolphin antigens of two antibodies not used to date in dolphins (anti-mouse iNOS and anti-mouse Foxp3). The most common type of cholangitis found was chronic granulomatous cholangitis, associated with the presence of the parasite Campula spp., or its eggs in bile ducts. The cellular composition of the hepatic inflammatory infiltrate associated to chronic parasitic cholangitis was closely similar to that found in the cortex of control lymph nodes, including the presence of S100(+) and MHC class II(+) dendritic-like cells in lymphoid follicles and interfollicular areas. Only occasional macrophages expressed iNOS, whereas Foxp3(+) lymphocytes were not found in any of the lesions described in the different types of cholangitis.
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Cetáceos , Colangitis/veterinaria , Infecciones por Trematodos/veterinaria , Animales , Anticuerpos Antihelmínticos/sangre , Colangitis/parasitología , Hígado/parasitología , Hígado/patología , Trematodos/clasificación , Infecciones por Trematodos/parasitología , Infecciones por Trematodos/patologíaRESUMEN
BACKGROUND: Delphi technique allows developing a multidisciplinary consensus to establish solutions. AIM: To identify barriers and solutions to improve control in patients with Type-2 Diabetes Mellitus (DM2). METHODS: An observational study using the 2-round Delphi technique (June-August 2011). A panel of 108 experts in DM2 from medical and nursing fields (primary care providers and specialists) from different regions completed via email a questionnaire with 41 Likert statements and 9 scores for each one. Level of agreement was assessed using measures of central tendency and dispersion. We analysed commonalities/differences between the two groups (Kappa index and McNemar chi-square). RESULTS: Response rate: 65%. Degree of agreement: 63.4% (95% CI 48.7-78.1%) in medicine, and 78.1% (95% CI 65.4-90.8) in nursing (p > 0.05). Overall level of agreement: Kappa = 0.43, (χ(2) = 2.5 p > 0.05). Regarding non-compliance with therapy, it improves with: the information to the partner/family/caregiver, patient education degree in diabetes, patient motivation and ability to share and agree on decisions with the patient. Clinical inertia improves with: motivation degree of healthcare professionals and the calculation of cardiovascular risk; and gets worse with: the shortage of time in consultation, absence of data in medical record, border high limits measurements accepted as normal readings, lack of a treatment goals, lack of teamwork (Physician/Nurse), scarcity of resources and lack of alarm systems in the electronic medical record on goals to achieve. CONCLUSION: The participants achieved an agreement in interventions in non-therapeutic compliance and clinical inertia to improve DM2 control.
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Diabetes Mellitus Tipo 2/prevención & control , Cumplimiento de la Medicación , Práctica Profesional/normas , Actitud del Personal de Salud , Consenso , Técnica Delphi , Conocimientos, Actitudes y Práctica en Salud , Humanos , España , Encuestas y Cuestionarios , Insuficiencia del TratamientoRESUMEN
INTRODUCTION AND OBJECTIVES: The advisability of implanting a stent in carotid near-occlusion stenosis is a controversial topic. We have assessed procedural and clinical implications of stent implantation for carotid artery disease with near occlusion. METHODS: We included 205 patients who underwent carotid artery revascularisation with a stent. The group of patients with near-occlusion stenosis (n=54)was compared to the rest of the population (n=151). RESULTS: No differences were found between groups for age, sex, and the percentage of symptomatic patients (three-quarters of the population). Carotid stent revascularisation for near-occlusion stenosis presented a high procedural success rate (96%) similar to that of revascularisation processes for other lesions (98%). Stenting in cases of near-occlusion stenosis required increased use of proximal protection (54% vs. 20.5%, P<.001) and predilation (33% vs. 17%, P=.01). The process to repair near-occlusion stenosis cause increased detachment of plaque, as shown by higher percentages of macroscopic plaque captured by protection devices (18.5% vs. 7%, P=.01) and of perioperative ischaemic brain lesions (47% vs 31%, P = .07). At 30 days of follow-up, the tendency toward adverse neurological events (death, major and minor stroke) was higher in the near-occlusion group (9.2% vs. 3.2%, P=.08). CONCLUSIONS: Stent revascularisation for near-occlusion carotid stenosis has a high procedural success rate; however, its higher plaque load was responsible for the increased rate of ischaemic brain lesions and adverse neurovascular events at 30 days post-procedure.
Asunto(s)
Arterias Carótidas/cirugía , Estenosis Carotídea/cirugía , Stents , Anciano , Anciano de 80 o más Años , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/patología , Revascularización Cerebral , Femenino , Humanos , Angiografía por Resonancia Magnética , Imagen por Resonancia Magnética , Masculino , Persona de Mediana EdadRESUMEN
Macrocytosis, the hallmark of cobalamin/folate deficiency anemia, is frequently absent. Clinicians have to be aware of coexisting conditions that can mask the macrocytosis expression of megaloblastic anemia, especially iron deficiency. The objective of this work was to investigate the degree of overlap between iron deficiency anemia (IDA) and cobalamin deficiency and to develop a predictive model for differentiating IDA from combined deficiency. A prospective case and control study was carried out to investigate vitamin B12 and folate status in iron deficiency anemia. A total of 658 patients were recruited, 41 of whom (6.2 %) were excluded. The remaining 617 subjects consisted of 130 controls and 487 with IDA. Low vitamin B12 (LB12) was considered when serum vitamin B12 was ≤200 pmol/L. High serum homocysteine (Hcy) was defined by Hcy >17 µM/L. A multivariate analysis (including a logistic regression) was performed to develop a diagnostic model. Low vitamin B12 levels were found in 17.8 % of IDA subjects. Ten out of 11 subjects (91 %) with IDA and serum vitamin B12 (B12) ≤100 pmol/L showed vitamin B12 deficiency. Moreover, vitamin B12 deficiency was demonstrated in 48 % of cases with IDA and B12 between 101 and 150 pmol/L and in 40 % with IDA and B12 between 151 and 200 pmol/, respectively. As a result of multivariate logistic analysis, neutrophil counts and age predicted subjects with vitamin B12 ≤200 and Hcy >17 µmol/L, [Formula: see text]. Using the age of 60 as a cutoff, sensitivity was 91 % (39 out of the 43 patients with vitamin B12 deficiency and IDA were identified). In summary, low vitamin B12 was found in 18 % of patients with IDA. Vitamin B12 deficiency was demonstrated in many patients with LB12 and IDA. Age over 60 years was used to separate patients with combined deficiency (sensitivity 91 %). Therefore, for a diagnostic purpose, serum vitamin B12 should be evaluated in IDA patients over 60 years. This diagnostic model needs to be validated in a different population.
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Anemia Ferropénica/complicaciones , Anemia Ferropénica/diagnóstico , Técnicas y Procedimientos Diagnósticos , Homocisteína/análisis , Deficiencia de Vitamina B 12/complicaciones , Deficiencia de Vitamina B 12/diagnóstico , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Anemia Ferropénica/sangre , Estudios de Casos y Controles , Técnicas de Apoyo para la Decisión , Femenino , Hematología/métodos , Homocisteína/sangre , Humanos , Masculino , Persona de Mediana Edad , Análisis de Regresión , Sensibilidad y Especificidad , Vitamina B 12/análisis , Vitamina B 12/sangre , Deficiencia de Vitamina B 12/sangreRESUMEN
Milk fat globule-EGF factor 8 (MFG-E8) is a glycoprotein highly expressed in breast cancer that contributes to tumor progression through largely undefined mechanisms. By analyzing publicly available gene expression profiles of breast carcinomas, we found that MFG-E8 is highly expressed in primary and metastatic breast carcinomas, associated with absent estrogen receptor expression. Immunohistochemistry analysis of breast cancer biopsies revealed that MFG-E8 is expressed on the cell membrane as well as in the cytoplasm and nucleus. We also show that increased expression of MFG-E8 in mammary carcinoma cells increases their tumorigenicity in immunodeficient mice, and conversely, its downregulation reduces their in vivo growth. Moreover, expression of MFG-E8 in immortalized mammary epithelial cells promotes their growth and branching in three-dimensional collagen matrices and induces the expression of cyclins D1/D3 and N-cadherin. A mutant protein unable to bind integrins can in part exert these effects, indicating that MFG-E8 function is only partially dependent on integrin activation. We conclude that MFG-E8-dependent signaling stimulates cell proliferation and the acquisition of mesenchymal properties and contributes to mammary carcinoma development.
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Antígenos de Superficie/fisiología , Ciclina D1/metabolismo , Ciclina D3/metabolismo , Células Epiteliales/metabolismo , Neoplasias Mamarias Experimentales/metabolismo , Animales , Mama/metabolismo , Cadherinas/metabolismo , Línea Celular , Proliferación Celular , Transición Epitelial-Mesenquimal , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Ratones , Ratones SCID , Proteínas de la Leche , Trasplante de Neoplasias , Transducción de Señal/fisiologíaRESUMEN
PURPOSE: To quantify systematic and random patient set-up errors in breast and head and neck conventional irradiation and to evaluate a no-action level (NAL) protocol for systematic set-up error off-line correction in head and neck cancer and breast cancer patients. MATERIAL AND METHODS: Verification electronic portal images of orthogonal set-up fields were obtained daily for the initial four consecutive fractions for 20 patients treated for breast cancer and for 20 head and neck cancer patients. The calculated systematic error was used to shift the isocentre accordingly on the fifth treatment day. From then until the end of the treatment course, pair orthogonal portal images of set-up fields were obtained weekly. To assess the impact of the protocol, pre- and post-correction systematic errors were compared and PTV margins were estimated before and after correction using published margin recipes. RESULTS: Population systematic set-up error decreased in the breast cancer patient group after the implementation of NAL protocol from 4.0 to 1.7 mm on the x-axis, from 4.7 to 2.1 mm on the y-axis and from 2.8 to 0.9 mm on the z axis. The percentage of patients with individual systematic set-up error reduction was 80%, 90% and 80% on the x-, y and z-axes respectively. Population systematic set-up error decreased also in the head and neck cancer patient group from 2.3 to 1.1 mm on the x-axis, from 1.6 to 1.4 mm on the y-axis and from 1.7 to 0.7 mm on the z-axis. The percentage of patients with individual systematic set-up error reduction was 70%, 65% and 85% on the x-, y- and z-axes respectively. Margin reduction achievable with NAL protocol implementation on the x-, y- and z-axes was 6.3, 7.2 and 4.8 mm for breast cancer patients and 3.3, 0.6 and 2.8 mm for head and neck cancer patients. CONCLUSION: NAL off-line protocol is useful for systematic set-up error correction and PTV margin reduction in conventional breast and head and neck irradiation (AU)
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Humanos , Femenino , Neoplasias de la Mama/radioterapia , Carcinoma/radioterapia , Neoplasias de Cabeza y Cuello/radioterapia , Errores de Medicación/prevención & control , Planificación de la Radioterapia Asistida por Computador/métodos , Planificación de la Radioterapia Asistida por Computador/estadística & datos numéricos , Algoritmos , Procesamiento de Imagen Asistido por Computador/métodos , Procesamiento de Imagen Asistido por Computador/estadística & datos numéricos , Posicionamiento del Paciente/métodos , Planificación de la Radioterapia Asistida por Computador/efectos adversos , Radioterapia Conformacional/efectos adversos , Radioterapia Conformacional/métodos , Radioterapia Conformacional/estadística & datos numéricosRESUMEN
PURPOSE: Organ motion should be taken into account for image-guided fractionated radiotherapy. A deformable segmentation and registration method was developed for inter-and intra-fraction organ motion planning and evaluation. METHODS: Energy minimizing active models were synthesized for tracking a set of organs delineated by regions of interest (ROI) in radiotherapy treatment. The initial model consists of a surface deformed to match the ROI contour by geometrical properties, following a heat flow model. The deformable segmentation model was tested using a Shepp-Logan head CT simulation, and different quantitative metrics were applied such as ROC analysis, Jaccard index, Dice coefficient and Hausdorff distance. RESULTS: Experimental evaluation of automated versus manual segmentation was done for the cardiac, thoracic and pelvic regions. The method has been quantitatively validated, obtaining an average of 93.3 and 99.2% for the sensitivity and specificity, respectively, 90.79% for the Jaccard index, 95.15% for the Dice coefficient and 0.96% mm for the Hausdorff distance. CONCLUSIONS: Model-based deformable segmentation was developed and tested for image-guided radiotherapy treatment planning. The method is efficient, robust and has sufficient accuracy for 2D CT data without markers.
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Modelos Anatómicos , Radioterapia Asistida por Computador/métodos , Algoritmos , Corazón/efectos de la radiación , Humanos , Pulmón/efectos de la radiación , Movimiento (Física) , Curva ROC , Radiografía Abdominal , Radiografía Torácica , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos XRESUMEN
Cytogenetic analysis of 58 boars at an artificial insemination (AI) centre revealed the presence of a reciprocal chromosome translocation, rcp(1;11)(q-;p+), in two Duroc boars. Pedigree analysis of these two boars suggested familial transmission of the chromosome rearrangement. The reproductive consequences of this translocation were determined in a herd of sows that had received semen doses from these and other boars. All sows underwent multiple AI, with different groups established retrospectively depending on the percentage of semen doses provided by the carrier boars ([number of carrier boar doses/total number doses provided] x 100): 0%, 25%, 50%, 75%, 100%. The fertility rates (percentage of successful multiple AIs/total multiple AIs) recorded for multiple AI including semen doses from the carrier boars were not significantly different from those recorded when all semen doses were supplied by normal-karyotype boars. A reduction in litter size of 29.38% was observed, however, in litters sired by one of the carrier boars when its participation in multiple AI was 100%. The number of live-born piglets per litter gradually decreased (P<0.05) as the percentage participation in multiple AI (25, 50, or 75%) of the carrier boar increased. In addition, both carrier boars sired some piglets with signs of cleft palate and complex malformations of the front legs; these died soon after birth. In conclusion, the boars carrying the translocation rcp(1;11)(q-;p+) showed reduced reproductive performance.
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Inseminación Artificial/veterinaria , Reproducción/genética , Enfermedades de los Porcinos/genética , Translocación Genética/genética , Animales , Fisura del Paladar/genética , Fisura del Paladar/veterinaria , Fertilidad/genética , Cariotipificación/veterinaria , Deformidades Congénitas de las Extremidades/genética , Deformidades Congénitas de las Extremidades/veterinaria , Tamaño de la Camada/genética , Nacimiento Vivo/genética , Nacimiento Vivo/veterinaria , Masculino , PorcinosRESUMEN
PURPOSE: A method for performing fast simulations of absorbed dose using a patient's computerized tomography (CT) scan without explicitly relying on a calibration curve is presented. METHODS: The method is based on geometrical deformations performed on a standard voxelized human phantom. This involves spatially transforming the human phantom to align it with the patient CT image. Since the chemical composition and density of each voxel are given in the phantom data, a calibration curve is not used in the proposed method. For this study, the Monte Carlo (MC) code PENELOPE has been used as the simulation of reference. The results obtained with PENELOPE simulations are compared to those obtained with PENFAST and with the collapsed cone convolution algorithm implemented in a commercial treatment planning system. RESULTS: The comparisons of the absorbed doses calculated with the different algorithms on two patient CTs and the corresponding deformed phantoms show a maximum distance to agreement of 2 mm, and in general, the obtained absorbed dose distributions are compatible within the reached statistical uncertainty. The validity of the deformation method for a broad range of patients is shown using MC simulations in random density phantoms. A PENFAST simulation of a 6 MV photon beam impinging on a patient CT reaches 2% statistical uncertainty in the absorbed dose, in a 0.1 cm3 voxel along the central axis, in 10 min running on a single core of a 2.8 GHz CPU. CONCLUSIONS: The proposed method of the absorbed dose calculation in a deformed voxelized phantom allows for dosimetric studies in the geometry of a patient CT scan. This is due to the fact that the chemical composition and material density of the phantom are known. Furthermore, simulation using the phantom geometry can provide dosimetric information for each organ. The method can be used for quality assurance procedures. In relation to PENFAST, it is shown that a purely condensed-history algorithm (class I) can be used for absorbed dose estimation in patient CTs.
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Simulación por Computador , Modelos Biológicos , Método de Montecarlo , Fantasmas de Imagen , Dosis de Radiación , Tomografía Computarizada por Rayos X/métodos , Algoritmos , Humanos , Pelvis/diagnóstico por imagen , Radiografía Torácica , Programas Informáticos , Factores de TiempoRESUMEN
BACKGROUND: Respiratory muscle unloading during exercise could improve locomotor muscle oxygenation by increasing oxygen delivery (higher cardiac output and/or arterial oxygen content) in patients with chronic obstructive pulmonary disease (COPD). METHODS: Sixteen non-hypoxaemic men (forced expiratory volume in 1 s 42.2 (13.9)% predicted) undertook, on different days, two constant work rate (70-80% peak) exercise tests receiving proportional assisted ventilation (PAV) or sham ventilation. Relative changes (Delta%) in deoxyhaemoglobin (HHb), oxyhaemoglobin (O(2)Hb), tissue oxygenation index (TOI) and total haemoglobin (Hb(tot)) in the vastus lateralis muscle were measured by near-infrared spectroscopy. In order to estimate oxygen delivery (Do(2)est, l/min), cardiac output and oxygen saturation (Spo(2)) were continuously monitored by impedance cardiography and pulse oximetry, respectively. RESULTS: Exercise tolerance (Tlim) and oxygen uptake were increased with PAV compared with sham ventilation. In contrast, end-exercise blood lactate/Tlim and leg effort/Tlim ratios were lower with PAV (p<0.05). There were no between-treatment differences in cardiac output and Spo(2) either at submaximal exercise or at Tlim (ie, Do(2)est remained unchanged with PAV; p>0.05). Leg muscle oxygenation, however, was significantly enhanced with PAV as the exercise-related decrease in Delta(O(2)Hb)% was lessened and TOI was improved; moreover, Delta(Hb(tot))%, an index of local blood volume, was increased compared with sham ventilation (p<0.01). CONCLUSIONS: Respiratory muscle unloading during high-intensity exercise can improve peripheral muscle oxygenation despite unaltered systemic Do(2 )in patients with advanced COPD. These findings might indicate that a fraction of the available cardiac output had been redirected from ventilatory to appendicular muscles as a consequence of respiratory muscle unloading.
Asunto(s)
Ejercicio Físico/fisiología , Oxígeno/fisiología , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Músculos Respiratorios/fisiología , Dióxido de Carbono/sangre , Dióxido de Carbono/fisiología , Gasto Cardíaco/fisiología , Tolerancia al Ejercicio/fisiología , Humanos , Masculino , Músculo Esquelético/fisiología , Oxígeno/sangre , Consumo de Oxígeno/fisiología , Presión Parcial , Respiración Artificial , Espectroscopía Infrarroja CortaRESUMEN
Las estatinas han demostrado que son útiles en la prevención de la enfermedad cardiovascular: infarto de miocardio, ictus, mortalidad cardiovascular y total. Los beneficios del tratamiento se manifiestan sobre todo en pacientes que han padecido una enfermedad cardiovascular o con un riesgo cardiovascular alto. Las dosis mínimas eficaces de las estatinas en la prevención de la enfermedad cardiovascular son: atorvastatina 10 mg/dia, simvastatina 20-40 mg/dia, lovastatina 20-40 mg/dia y pravastatina 40 mg/dia. Estas dosis consiguen un 20% de reducción del cLDL (colesterol de las lipoproteínas de baja densidad) en los ensayos clínicos. La hepatotoxicidad y miotoxicidad son los efectos secundarios más importantes de las estatinas. La elevación de las transaminasas y la aparición de síntomas musculares son la forma de detectarlos. Las estatinas están indicadas para el tratamiento de la enfermedad cardiovascular o en un paciente con riesgo cardiovascular alto cuando el cLDL sea superior a 115 mg/dl
The statins have demonstrated that they are useful in the prevention of the cardiovascular illness: myocardial infarction, stroke, cardiovascular and total mortality. The benefits of the treatment are manifested mainly in patients that have suffered a cardiovascular illness or with a high cardiovascular risk. The effective minimum dose daily of the statins in the prevention of the cardiovascular illness is: atorvastatin 10 mg, simvastatin 20-40 mg, lovastatin 20- 40 mg and pravastatin 40 mg. These doses get 20% of reduction of the cLDL (cholesterol of the lipoproteins of low density) in the randomised clinical trials. The hepatic and muscular effects are the most important adverse events. The elevation of the AST or ALT and the appearance of muscular symptoms are the form of detecting them. The treatment with statins is suitable for patients with cardiovascular illness or with high cardiovascular risk when the cLDL is superior to 115 mg/dl